diff options
Diffstat (limited to 'kernel')
98 files changed, 6654 insertions, 2210 deletions
diff --git a/kernel/Makefile b/kernel/Makefile index d754e0be1176..10ef068f598d 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -41,9 +41,6 @@ UBSAN_SANITIZE_kcov.o := n KMSAN_SANITIZE_kcov.o := n CFLAGS_kcov.o := $(call cc-option, -fno-conserve-stack) -fno-stack-protector -# Don't instrument error handlers -CFLAGS_REMOVE_cfi.o := $(CC_FLAGS_CFI) - obj-y += sched/ obj-y += locking/ obj-y += power/ @@ -69,6 +66,7 @@ endif obj-$(CONFIG_UID16) += uid16.o obj-$(CONFIG_MODULE_SIG_FORMAT) += module_signature.o obj-$(CONFIG_KALLSYMS) += kallsyms.o +obj-$(CONFIG_KALLSYMS_SELFTEST) += kallsyms_selftest.o obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o obj-$(CONFIG_CRASH_CORE) += crash_core.o obj-$(CONFIG_KEXEC_CORE) += kexec_core.o diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile index 341c94f208f4..3a12e6b400a2 100644 --- a/kernel/bpf/Makefile +++ b/kernel/bpf/Makefile @@ -25,7 +25,7 @@ ifeq ($(CONFIG_PERF_EVENTS),y) obj-$(CONFIG_BPF_SYSCALL) += stackmap.o endif ifeq ($(CONFIG_CGROUPS),y) -obj-$(CONFIG_BPF_SYSCALL) += cgroup_iter.o +obj-$(CONFIG_BPF_SYSCALL) += cgroup_iter.o bpf_cgrp_storage.o endif obj-$(CONFIG_CGROUP_BPF) += cgroup.o ifeq ($(CONFIG_INET),y) diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index 832b2659e96e..484706959556 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -306,14 +306,6 @@ static int array_map_get_next_key(struct bpf_map *map, void *key, void *next_key return 0; } -static void check_and_free_fields(struct bpf_array *arr, void *val) -{ - if (map_value_has_timer(&arr->map)) - bpf_timer_cancel_and_free(val + arr->map.timer_off); - if (map_value_has_kptrs(&arr->map)) - bpf_map_free_kptrs(&arr->map, val); -} - /* Called from syscall or from eBPF program */ static int array_map_update_elem(struct bpf_map *map, void *key, void *value, u64 map_flags) @@ -335,13 +327,13 @@ static int array_map_update_elem(struct bpf_map *map, void *key, void *value, return -EEXIST; if (unlikely((map_flags & BPF_F_LOCK) && - !map_value_has_spin_lock(map))) + !btf_record_has_field(map->record, BPF_SPIN_LOCK))) return -EINVAL; if (array->map.map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { val = this_cpu_ptr(array->pptrs[index & array->index_mask]); copy_map_value(map, val, value); - check_and_free_fields(array, val); + bpf_obj_free_fields(array->map.record, val); } else { val = array->value + (u64)array->elem_size * (index & array->index_mask); @@ -349,7 +341,7 @@ static int array_map_update_elem(struct bpf_map *map, void *key, void *value, copy_map_value_locked(map, val, value, false); else copy_map_value(map, val, value); - check_and_free_fields(array, val); + bpf_obj_free_fields(array->map.record, val); } return 0; } @@ -386,7 +378,7 @@ int bpf_percpu_array_update(struct bpf_map *map, void *key, void *value, pptr = array->pptrs[index & array->index_mask]; for_each_possible_cpu(cpu) { copy_map_value_long(map, per_cpu_ptr(pptr, cpu), value + off); - check_and_free_fields(array, per_cpu_ptr(pptr, cpu)); + bpf_obj_free_fields(array->map.record, per_cpu_ptr(pptr, cpu)); off += size; } rcu_read_unlock(); @@ -409,12 +401,12 @@ static void array_map_free_timers(struct bpf_map *map) struct bpf_array *array = container_of(map, struct bpf_array, map); int i; - /* We don't reset or free kptr on uref dropping to zero. */ - if (!map_value_has_timer(map)) + /* We don't reset or free fields other than timer on uref dropping to zero. */ + if (!btf_record_has_field(map->record, BPF_TIMER)) return; for (i = 0; i < array->map.max_entries; i++) - bpf_timer_cancel_and_free(array_map_elem_ptr(array, i) + map->timer_off); + bpf_obj_free_timer(map->record, array_map_elem_ptr(array, i)); } /* Called when map->refcnt goes to zero, either from workqueue or from syscall */ @@ -423,22 +415,21 @@ static void array_map_free(struct bpf_map *map) struct bpf_array *array = container_of(map, struct bpf_array, map); int i; - if (map_value_has_kptrs(map)) { + if (!IS_ERR_OR_NULL(map->record)) { if (array->map.map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { for (i = 0; i < array->map.max_entries; i++) { void __percpu *pptr = array->pptrs[i & array->index_mask]; int cpu; for_each_possible_cpu(cpu) { - bpf_map_free_kptrs(map, per_cpu_ptr(pptr, cpu)); + bpf_obj_free_fields(map->record, per_cpu_ptr(pptr, cpu)); cond_resched(); } } } else { for (i = 0; i < array->map.max_entries; i++) - bpf_map_free_kptrs(map, array_map_elem_ptr(array, i)); + bpf_obj_free_fields(map->record, array_map_elem_ptr(array, i)); } - bpf_map_free_kptr_off_tab(map); } if (array->map.map_type == BPF_MAP_TYPE_PERCPU_ARRAY) diff --git a/kernel/bpf/bpf_cgrp_storage.c b/kernel/bpf/bpf_cgrp_storage.c new file mode 100644 index 000000000000..6cdf6d9ed91d --- /dev/null +++ b/kernel/bpf/bpf_cgrp_storage.c @@ -0,0 +1,246 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2022 Meta Platforms, Inc. and affiliates. + */ + +#include <linux/types.h> +#include <linux/bpf.h> +#include <linux/bpf_local_storage.h> +#include <uapi/linux/btf.h> +#include <linux/btf_ids.h> + +DEFINE_BPF_STORAGE_CACHE(cgroup_cache); + +static DEFINE_PER_CPU(int, bpf_cgrp_storage_busy); + +static void bpf_cgrp_storage_lock(void) +{ + migrate_disable(); + this_cpu_inc(bpf_cgrp_storage_busy); +} + +static void bpf_cgrp_storage_unlock(void) +{ + this_cpu_dec(bpf_cgrp_storage_busy); + migrate_enable(); +} + +static bool bpf_cgrp_storage_trylock(void) +{ + migrate_disable(); + if (unlikely(this_cpu_inc_return(bpf_cgrp_storage_busy) != 1)) { + this_cpu_dec(bpf_cgrp_storage_busy); + migrate_enable(); + return false; + } + return true; +} + +static struct bpf_local_storage __rcu **cgroup_storage_ptr(void *owner) +{ + struct cgroup *cg = owner; + + return &cg->bpf_cgrp_storage; +} + +void bpf_cgrp_storage_free(struct cgroup *cgroup) +{ + struct bpf_local_storage *local_storage; + bool free_cgroup_storage = false; + unsigned long flags; + + rcu_read_lock(); + local_storage = rcu_dereference(cgroup->bpf_cgrp_storage); + if (!local_storage) { + rcu_read_unlock(); + return; + } + + bpf_cgrp_storage_lock(); + raw_spin_lock_irqsave(&local_storage->lock, flags); + free_cgroup_storage = bpf_local_storage_unlink_nolock(local_storage); + raw_spin_unlock_irqrestore(&local_storage->lock, flags); + bpf_cgrp_storage_unlock(); + rcu_read_unlock(); + + if (free_cgroup_storage) + kfree_rcu(local_storage, rcu); +} + +static struct bpf_local_storage_data * +cgroup_storage_lookup(struct cgroup *cgroup, struct bpf_map *map, bool cacheit_lockit) +{ + struct bpf_local_storage *cgroup_storage; + struct bpf_local_storage_map *smap; + + cgroup_storage = rcu_dereference_check(cgroup->bpf_cgrp_storage, + bpf_rcu_lock_held()); + if (!cgroup_storage) + return NULL; + + smap = (struct bpf_local_storage_map *)map; + return bpf_local_storage_lookup(cgroup_storage, smap, cacheit_lockit); +} + +static void *bpf_cgrp_storage_lookup_elem(struct bpf_map *map, void *key) +{ + struct bpf_local_storage_data *sdata; + struct cgroup *cgroup; + int fd; + + fd = *(int *)key; + cgroup = cgroup_get_from_fd(fd); + if (IS_ERR(cgroup)) + return ERR_CAST(cgroup); + + bpf_cgrp_storage_lock(); + sdata = cgroup_storage_lookup(cgroup, map, true); + bpf_cgrp_storage_unlock(); + cgroup_put(cgroup); + return sdata ? sdata->data : NULL; +} + +static int bpf_cgrp_storage_update_elem(struct bpf_map *map, void *key, + void *value, u64 map_flags) +{ + struct bpf_local_storage_data *sdata; + struct cgroup *cgroup; + int fd; + + fd = *(int *)key; + cgroup = cgroup_get_from_fd(fd); + if (IS_ERR(cgroup)) + return PTR_ERR(cgroup); + + bpf_cgrp_storage_lock(); + sdata = bpf_local_storage_update(cgroup, (struct bpf_local_storage_map *)map, + value, map_flags, GFP_ATOMIC); + bpf_cgrp_storage_unlock(); + cgroup_put(cgroup); + return PTR_ERR_OR_ZERO(sdata); +} + +static int cgroup_storage_delete(struct cgroup *cgroup, struct bpf_map *map) +{ + struct bpf_local_storage_data *sdata; + + sdata = cgroup_storage_lookup(cgroup, map, false); + if (!sdata) + return -ENOENT; + + bpf_selem_unlink(SELEM(sdata), true); + return 0; +} + +static int bpf_cgrp_storage_delete_elem(struct bpf_map *map, void *key) +{ + struct cgroup *cgroup; + int err, fd; + + fd = *(int *)key; + cgroup = cgroup_get_from_fd(fd); + if (IS_ERR(cgroup)) + return PTR_ERR(cgroup); + + bpf_cgrp_storage_lock(); + err = cgroup_storage_delete(cgroup, map); + bpf_cgrp_storage_unlock(); + cgroup_put(cgroup); + return err; +} + +static int notsupp_get_next_key(struct bpf_map *map, void *key, void *next_key) +{ + return -ENOTSUPP; +} + +static struct bpf_map *cgroup_storage_map_alloc(union bpf_attr *attr) +{ + return bpf_local_storage_map_alloc(attr, &cgroup_cache); +} + +static void cgroup_storage_map_free(struct bpf_map *map) +{ + bpf_local_storage_map_free(map, &cgroup_cache, NULL); +} + +/* *gfp_flags* is a hidden argument provided by the verifier */ +BPF_CALL_5(bpf_cgrp_storage_get, struct bpf_map *, map, struct cgroup *, cgroup, + void *, value, u64, flags, gfp_t, gfp_flags) +{ + struct bpf_local_storage_data *sdata; + + WARN_ON_ONCE(!bpf_rcu_lock_held()); + if (flags & ~(BPF_LOCAL_STORAGE_GET_F_CREATE)) + return (unsigned long)NULL; + + if (!cgroup) + return (unsigned long)NULL; + + if (!bpf_cgrp_storage_trylock()) + return (unsigned long)NULL; + + sdata = cgroup_storage_lookup(cgroup, map, true); + if (sdata) + goto unlock; + + /* only allocate new storage, when the cgroup is refcounted */ + if (!percpu_ref_is_dying(&cgroup->self.refcnt) && + (flags & BPF_LOCAL_STORAGE_GET_F_CREATE)) + sdata = bpf_local_storage_update(cgroup, (struct bpf_local_storage_map *)map, + value, BPF_NOEXIST, gfp_flags); + +unlock: + bpf_cgrp_storage_unlock(); + return IS_ERR_OR_NULL(sdata) ? (unsigned long)NULL : (unsigned long)sdata->data; +} + +BPF_CALL_2(bpf_cgrp_storage_delete, struct bpf_map *, map, struct cgroup *, cgroup) +{ + int ret; + + WARN_ON_ONCE(!bpf_rcu_lock_held()); + if (!cgroup) + return -EINVAL; + + if (!bpf_cgrp_storage_trylock()) + return -EBUSY; + + ret = cgroup_storage_delete(cgroup, map); + bpf_cgrp_storage_unlock(); + return ret; +} + +const struct bpf_map_ops cgrp_storage_map_ops = { + .map_meta_equal = bpf_map_meta_equal, + .map_alloc_check = bpf_local_storage_map_alloc_check, + .map_alloc = cgroup_storage_map_alloc, + .map_free = cgroup_storage_map_free, + .map_get_next_key = notsupp_get_next_key, + .map_lookup_elem = bpf_cgrp_storage_lookup_elem, + .map_update_elem = bpf_cgrp_storage_update_elem, + .map_delete_elem = bpf_cgrp_storage_delete_elem, + .map_check_btf = bpf_local_storage_map_check_btf, + .map_btf_id = &bpf_local_storage_map_btf_id[0], + .map_owner_storage_ptr = cgroup_storage_ptr, +}; + +const struct bpf_func_proto bpf_cgrp_storage_get_proto = { + .func = bpf_cgrp_storage_get, + .gpl_only = false, + .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL, + .arg1_type = ARG_CONST_MAP_PTR, + .arg2_type = ARG_PTR_TO_BTF_ID, + .arg2_btf_id = &bpf_cgroup_btf_id[0], + .arg3_type = ARG_PTR_TO_MAP_VALUE_OR_NULL, + .arg4_type = ARG_ANYTHING, +}; + +const struct bpf_func_proto bpf_cgrp_storage_delete_proto = { + .func = bpf_cgrp_storage_delete, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_CONST_MAP_PTR, + .arg2_type = ARG_PTR_TO_BTF_ID, + .arg2_btf_id = &bpf_cgroup_btf_id[0], +}; diff --git a/kernel/bpf/bpf_inode_storage.c b/kernel/bpf/bpf_inode_storage.c index 5f7683b19199..05f4c66c9089 100644 --- a/kernel/bpf/bpf_inode_storage.c +++ b/kernel/bpf/bpf_inode_storage.c @@ -56,11 +56,9 @@ static struct bpf_local_storage_data *inode_storage_lookup(struct inode *inode, void bpf_inode_storage_free(struct inode *inode) { - struct bpf_local_storage_elem *selem; struct bpf_local_storage *local_storage; bool free_inode_storage = false; struct bpf_storage_blob *bsb; - struct hlist_node *n; bsb = bpf_inode(inode); if (!bsb) @@ -74,30 +72,11 @@ void bpf_inode_storage_free(struct inode *inode) return; } - /* Neither the bpf_prog nor the bpf-map's syscall - * could be modifying the local_storage->list now. - * Thus, no elem can be added-to or deleted-from the - * local_storage->list by the bpf_prog or by the bpf-map's syscall. - * - * It is racing with bpf_local_storage_map_free() alone - * when unlinking elem from the local_storage->list and - * the map's bucket->list. - */ raw_spin_lock_bh(&local_storage->lock); - hlist_for_each_entry_safe(selem, n, &local_storage->list, snode) { - /* Always unlink from map before unlinking from - * local_storage. - */ - bpf_selem_unlink_map(selem); - free_inode_storage = bpf_selem_unlink_storage_nolock( - local_storage, selem, false, false); - } + free_inode_storage = bpf_local_storage_unlink_nolock(local_storage); raw_spin_unlock_bh(&local_storage->lock); rcu_read_unlock(); - /* free_inoode_storage should always be true as long as - * local_storage->list was non-empty. - */ if (free_inode_storage) kfree_rcu(local_storage, rcu); } @@ -226,27 +205,14 @@ static int notsupp_get_next_key(struct bpf_map *map, void *key, static struct bpf_map *inode_storage_map_alloc(union bpf_attr *attr) { - struct bpf_local_storage_map *smap; - - smap = bpf_local_storage_map_alloc(attr); - if (IS_ERR(smap)) - return ERR_CAST(smap); - - smap->cache_idx = bpf_local_storage_cache_idx_get(&inode_cache); - return &smap->map; + return bpf_local_storage_map_alloc(attr, &inode_cache); } static void inode_storage_map_free(struct bpf_map *map) { - struct bpf_local_storage_map *smap; - - smap = (struct bpf_local_storage_map *)map; - bpf_local_storage_cache_idx_free(&inode_cache, smap->cache_idx); - bpf_local_storage_map_free(smap, NULL); + bpf_local_storage_map_free(map, &inode_cache, NULL); } -BTF_ID_LIST_SINGLE(inode_storage_map_btf_ids, struct, - bpf_local_storage_map) const struct bpf_map_ops inode_storage_map_ops = { .map_meta_equal = bpf_map_meta_equal, .map_alloc_check = bpf_local_storage_map_alloc_check, @@ -257,7 +223,7 @@ const struct bpf_map_ops inode_storage_map_ops = { .map_update_elem = bpf_fd_inode_storage_update_elem, .map_delete_elem = bpf_fd_inode_storage_delete_elem, .map_check_btf = bpf_local_storage_map_check_btf, - .map_btf_id = &inode_storage_map_btf_ids[0], + .map_btf_id = &bpf_local_storage_map_btf_id[0], .map_owner_storage_ptr = inode_storage_ptr, }; diff --git a/kernel/bpf/bpf_local_storage.c b/kernel/bpf/bpf_local_storage.c index f27fa5ba7d72..b39a46e8fb08 100644 --- a/kernel/bpf/bpf_local_storage.c +++ b/kernel/bpf/bpf_local_storage.c @@ -88,8 +88,14 @@ void bpf_local_storage_free_rcu(struct rcu_head *rcu) { struct bpf_local_storage *local_storage; + /* If RCU Tasks Trace grace period implies RCU grace period, do + * kfree(), else do kfree_rcu(). + */ local_storage = container_of(rcu, struct bpf_local_storage, rcu); - kfree_rcu(local_storage, rcu); + if (rcu_trace_implies_rcu_gp()) + kfree(local_storage); + else + kfree_rcu(local_storage, rcu); } static void bpf_selem_free_rcu(struct rcu_head *rcu) @@ -97,16 +103,19 @@ static void bpf_selem_free_rcu(struct rcu_head *rcu) struct bpf_local_storage_elem *selem; selem = container_of(rcu, struct bpf_local_storage_elem, rcu); - kfree_rcu(selem, rcu); + if (rcu_trace_implies_rcu_gp()) + kfree(selem); + else + kfree_rcu(selem, rcu); } /* local_storage->lock must be held and selem->local_storage == local_storage. * The caller must ensure selem->smap is still valid to be * dereferenced for its smap->elem_size and smap->cache_idx. */ -bool bpf_selem_unlink_storage_nolock(struct bpf_local_storage *local_storage, - struct bpf_local_storage_elem *selem, - bool uncharge_mem, bool use_trace_rcu) +static bool bpf_selem_unlink_storage_nolock(struct bpf_local_storage *local_storage, + struct bpf_local_storage_elem *selem, + bool uncharge_mem, bool use_trace_rcu) { struct bpf_local_storage_map *smap; bool free_local_storage; @@ -233,6 +242,7 @@ void bpf_selem_unlink(struct bpf_local_storage_elem *selem, bool use_trace_rcu) __bpf_selem_unlink_storage(selem, use_trace_rcu); } +/* If cacheit_lockit is false, this lookup function is lockless */ struct bpf_local_storage_data * bpf_local_storage_lookup(struct bpf_local_storage *local_storage, struct bpf_local_storage_map *smap, @@ -372,7 +382,7 @@ bpf_local_storage_update(void *owner, struct bpf_local_storage_map *smap, if (unlikely((map_flags & ~BPF_F_LOCK) > BPF_EXIST) || /* BPF_F_LOCK can only be used in a value with spin_lock */ unlikely((map_flags & BPF_F_LOCK) && - !map_value_has_spin_lock(&smap->map))) + !btf_record_has_field(smap->map.record, BPF_SPIN_LOCK))) return ERR_PTR(-EINVAL); if (gfp_flags == GFP_KERNEL && (map_flags & ~BPF_F_LOCK) != BPF_NOEXIST) @@ -491,7 +501,7 @@ unlock_err: return ERR_PTR(err); } -u16 bpf_local_storage_cache_idx_get(struct bpf_local_storage_cache *cache) +static u16 bpf_local_storage_cache_idx_get(struct bpf_local_storage_cache *cache) { u64 min_usage = U64_MAX; u16 i, res = 0; @@ -515,76 +525,14 @@ u16 bpf_local_storage_cache_idx_get(struct bpf_local_storage_cache *cache) return res; } -void bpf_local_storage_cache_idx_free(struct bpf_local_storage_cache *cache, - u16 idx) +static void bpf_local_storage_cache_idx_free(struct bpf_local_storage_cache *cache, + u16 idx) { spin_lock(&cache->idx_lock); cache->idx_usage_counts[idx]--; spin_unlock(&cache->idx_lock); } -void bpf_local_storage_map_free(struct bpf_local_storage_map *smap, - int __percpu *busy_counter) -{ - struct bpf_local_storage_elem *selem; - struct bpf_local_storage_map_bucket *b; - unsigned int i; - - /* Note that this map might be concurrently cloned from - * bpf_sk_storage_clone. Wait for any existing bpf_sk_storage_clone - * RCU read section to finish before proceeding. New RCU - * read sections should be prevented via bpf_map_inc_not_zero. - */ - synchronize_rcu(); - - /* bpf prog and the userspace can no longer access this map - * now. No new selem (of this map) can be added - * to the owner->storage or to the map bucket's list. - * - * The elem of this map can be cleaned up here - * or when the storage is freed e.g. - * by bpf_sk_storage_free() during __sk_destruct(). - */ - for (i = 0; i < (1U << smap->bucket_log); i++) { - b = &smap->buckets[i]; - - rcu_read_lock(); - /* No one is adding to b->list now */ - while ((selem = hlist_entry_safe( - rcu_dereference_raw(hlist_first_rcu(&b->list)), - struct bpf_local_storage_elem, map_node))) { - if (busy_counter) { - migrate_disable(); - this_cpu_inc(*busy_counter); - } - bpf_selem_unlink(selem, false); - if (busy_counter) { - this_cpu_dec(*busy_counter); - migrate_enable(); - } - cond_resched_rcu(); - } - rcu_read_unlock(); - } - - /* While freeing the storage we may still need to access the map. - * - * e.g. when bpf_sk_storage_free() has unlinked selem from the map - * which then made the above while((selem = ...)) loop - * exit immediately. - * - * However, while freeing the storage one still needs to access the - * smap->elem_size to do the uncharging in - * bpf_selem_unlink_storage_nolock(). - * - * Hence, wait another rcu grace period for the storage to be freed. - */ - synchronize_rcu(); - - kvfree(smap->buckets); - bpf_map_area_free(smap); -} - int bpf_local_storage_map_alloc_check(union bpf_attr *attr) { if (attr->map_flags & ~BPF_LOCAL_STORAGE_CREATE_FLAG_MASK || @@ -604,7 +552,7 @@ int bpf_local_storage_map_alloc_check(union bpf_attr *attr) return 0; } -struct bpf_local_storage_map *bpf_local_storage_map_alloc(union bpf_attr *attr) +static struct bpf_local_storage_map *__bpf_local_storage_map_alloc(union bpf_attr *attr) { struct bpf_local_storage_map *smap; unsigned int i; @@ -654,3 +602,117 @@ int bpf_local_storage_map_check_btf(const struct bpf_map *map, return 0; } + +bool bpf_local_storage_unlink_nolock(struct bpf_local_storage *local_storage) +{ + struct bpf_local_storage_elem *selem; + bool free_storage = false; + struct hlist_node *n; + + /* Neither the bpf_prog nor the bpf_map's syscall + * could be modifying the local_storage->list now. + * Thus, no elem can be added to or deleted from the + * local_storage->list by the bpf_prog or by the bpf_map's syscall. + * + * It is racing with bpf_local_storage_map_free() alone + * when unlinking elem from the local_storage->list and + * the map's bucket->list. + */ + hlist_for_each_entry_safe(selem, n, &local_storage->list, snode) { + /* Always unlink from map before unlinking from + * local_storage. + */ + bpf_selem_unlink_map(selem); + /* If local_storage list has only one element, the + * bpf_selem_unlink_storage_nolock() will return true. + * Otherwise, it will return false. The current loop iteration + * intends to remove all local storage. So the last iteration + * of the loop will set the free_cgroup_storage to true. + */ + free_storage = bpf_selem_unlink_storage_nolock( + local_storage, selem, false, false); + } + + return free_storage; +} + +struct bpf_map * +bpf_local_storage_map_alloc(union bpf_attr *attr, + struct bpf_local_storage_cache *cache) +{ + struct bpf_local_storage_map *smap; + + smap = __bpf_local_storage_map_alloc(attr); + if (IS_ERR(smap)) + return ERR_CAST(smap); + + smap->cache_idx = bpf_local_storage_cache_idx_get(cache); + return &smap->map; +} + +void bpf_local_storage_map_free(struct bpf_map *map, + struct bpf_local_storage_cache *cache, + int __percpu *busy_counter) +{ + struct bpf_local_storage_map_bucket *b; + struct bpf_local_storage_elem *selem; + struct bpf_local_storage_map *smap; + unsigned int i; + + smap = (struct bpf_local_storage_map *)map; + bpf_local_storage_cache_idx_free(cache, smap->cache_idx); + + /* Note that this map might be concurrently cloned from + * bpf_sk_storage_clone. Wait for any existing bpf_sk_storage_clone + * RCU read section to finish before proceeding. New RCU + * read sections should be prevented via bpf_map_inc_not_zero. + */ + synchronize_rcu(); + + /* bpf prog and the userspace can no longer access this map + * now. No new selem (of this map) can be added + * to the owner->storage or to the map bucket's list. + * + * The elem of this map can be cleaned up here + * or when the storage is freed e.g. + * by bpf_sk_storage_free() during __sk_destruct(). + */ + for (i = 0; i < (1U << smap->bucket_log); i++) { + b = &smap->buckets[i]; + + rcu_read_lock(); + /* No one is adding to b->list now */ + while ((selem = hlist_entry_safe( + rcu_dereference_raw(hlist_first_rcu(&b->list)), + struct bpf_local_storage_elem, map_node))) { + if (busy_counter) { + migrate_disable(); + this_cpu_inc(*busy_counter); + } + bpf_selem_unlink(selem, false); + if (busy_counter) { + this_cpu_dec(*busy_counter); + migrate_enable(); + } + cond_resched_rcu(); + } + rcu_read_unlock(); + } + + /* While freeing the storage we may still need to access the map. + * + * e.g. when bpf_sk_storage_free() has unlinked selem from the map + * which then made the above while((selem = ...)) loop + * exit immediately. + * + * However, while freeing the storage one still needs to access the + * smap->elem_size to do the uncharging in + * bpf_selem_unlink_storage_nolock(). + * + * Hence, wait another rcu grace period for the storage to be freed. + */ + synchronize_rcu(); + + kvfree(smap->buckets); + bpf_map_area_free(smap); +} diff --git a/kernel/bpf/bpf_lsm.c b/kernel/bpf/bpf_lsm.c index d6c9b3705f24..e14c822f8911 100644 --- a/kernel/bpf/bpf_lsm.c +++ b/kernel/bpf/bpf_lsm.c @@ -51,7 +51,6 @@ BTF_SET_END(bpf_lsm_current_hooks) */ BTF_SET_START(bpf_lsm_locked_sockopt_hooks) #ifdef CONFIG_SECURITY_NETWORK -BTF_ID(func, bpf_lsm_socket_sock_rcv_skb) BTF_ID(func, bpf_lsm_sock_graft) BTF_ID(func, bpf_lsm_inet_csk_clone) BTF_ID(func, bpf_lsm_inet_conn_established) @@ -151,6 +150,7 @@ BTF_ID_LIST_SINGLE(bpf_ima_inode_hash_btf_ids, struct, inode) static const struct bpf_func_proto bpf_ima_inode_hash_proto = { .func = bpf_ima_inode_hash, .gpl_only = false, + .might_sleep = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_BTF_ID, .arg1_btf_id = &bpf_ima_inode_hash_btf_ids[0], @@ -169,6 +169,7 @@ BTF_ID_LIST_SINGLE(bpf_ima_file_hash_btf_ids, struct, file) static const struct bpf_func_proto bpf_ima_file_hash_proto = { .func = bpf_ima_file_hash, .gpl_only = false, + .might_sleep = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_BTF_ID, .arg1_btf_id = &bpf_ima_file_hash_btf_ids[0], @@ -221,9 +222,9 @@ bpf_lsm_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_bprm_opts_set: return &bpf_bprm_opts_set_proto; case BPF_FUNC_ima_inode_hash: - return prog->aux->sleepable ? &bpf_ima_inode_hash_proto : NULL; + return &bpf_ima_inode_hash_proto; case BPF_FUNC_ima_file_hash: - return prog->aux->sleepable ? &bpf_ima_file_hash_proto : NULL; + return &bpf_ima_file_hash_proto; case BPF_FUNC_get_attach_cookie: return bpf_prog_has_trampoline(prog) ? &bpf_get_attach_cookie_proto : NULL; #ifdef CONFIG_NET @@ -343,11 +344,29 @@ BTF_ID(func, bpf_lsm_task_to_inode) BTF_ID(func, bpf_lsm_userns_create) BTF_SET_END(sleepable_lsm_hooks) +BTF_SET_START(untrusted_lsm_hooks) +BTF_ID(func, bpf_lsm_bpf_map_free_security) +BTF_ID(func, bpf_lsm_bpf_prog_alloc_security) +BTF_ID(func, bpf_lsm_bpf_prog_free_security) +BTF_ID(func, bpf_lsm_file_alloc_security) +BTF_ID(func, bpf_lsm_file_free_security) +#ifdef CONFIG_SECURITY_NETWORK +BTF_ID(func, bpf_lsm_sk_alloc_security) +BTF_ID(func, bpf_lsm_sk_free_security) +#endif /* CONFIG_SECURITY_NETWORK */ +BTF_ID(func, bpf_lsm_task_free) +BTF_SET_END(untrusted_lsm_hooks) + bool bpf_lsm_is_sleepable_hook(u32 btf_id) { return btf_id_set_contains(&sleepable_lsm_hooks, btf_id); } +bool bpf_lsm_is_trusted(const struct bpf_prog *prog) +{ + return !btf_id_set_contains(&untrusted_lsm_hooks, prog->aux->attach_btf_id); +} + const struct bpf_prog_ops lsm_prog_ops = { }; diff --git a/kernel/bpf/bpf_struct_ops.c b/kernel/bpf/bpf_struct_ops.c index 84b2d9dba79a..ece9870cab68 100644 --- a/kernel/bpf/bpf_struct_ops.c +++ b/kernel/bpf/bpf_struct_ops.c @@ -494,8 +494,7 @@ static int bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key, refcount_set(&kvalue->refcnt, 1); bpf_map_inc(map); - set_memory_ro((long)st_map->image, 1); - set_memory_x((long)st_map->image, 1); + set_memory_rox((long)st_map->image, 1); err = st_ops->reg(kdata); if (likely(!err)) { /* Pair with smp_load_acquire() during lookup_elem(). diff --git a/kernel/bpf/bpf_task_storage.c b/kernel/bpf/bpf_task_storage.c index 6f290623347e..1e486055a523 100644 --- a/kernel/bpf/bpf_task_storage.c +++ b/kernel/bpf/bpf_task_storage.c @@ -71,10 +71,8 @@ task_storage_lookup(struct task_struct *task, struct bpf_map *map, void bpf_task_storage_free(struct task_struct *task) { - struct bpf_local_storage_elem *selem; struct bpf_local_storage *local_storage; bool free_task_storage = false; - struct hlist_node *n; unsigned long flags; rcu_read_lock(); @@ -85,32 +83,13 @@ void bpf_task_storage_free(struct task_struct *task) return; } - /* Neither the bpf_prog nor the bpf-map's syscall - * could be modifying the local_storage->list now. - * Thus, no elem can be added-to or deleted-from the - * local_storage->list by the bpf_prog or by the bpf-map's syscall. - * - * It is racing with bpf_local_storage_map_free() alone - * when unlinking elem from the local_storage->list and - * the map's bucket->list. - */ bpf_task_storage_lock(); raw_spin_lock_irqsave(&local_storage->lock, flags); - hlist_for_each_entry_safe(selem, n, &local_storage->list, snode) { - /* Always unlink from map before unlinking from - * local_storage. - */ - bpf_selem_unlink_map(selem); - free_task_storage = bpf_selem_unlink_storage_nolock( - local_storage, selem, false, false); - } + free_task_storage = bpf_local_storage_unlink_nolock(local_storage); raw_spin_unlock_irqrestore(&local_storage->lock, flags); bpf_task_storage_unlock(); rcu_read_unlock(); - /* free_task_storage should always be true as long as - * local_storage->list was non-empty. - */ if (free_task_storage) kfree_rcu(local_storage, rcu); } @@ -184,7 +163,8 @@ out: return err; } -static int task_storage_delete(struct task_struct *task, struct bpf_map *map) +static int task_storage_delete(struct task_struct *task, struct bpf_map *map, + bool nobusy) { struct bpf_local_storage_data *sdata; @@ -192,6 +172,9 @@ static int task_storage_delete(struct task_struct *task, struct bpf_map *map) if (!sdata) return -ENOENT; + if (!nobusy) + return -EBUSY; + bpf_selem_unlink(SELEM(sdata), true); return 0; @@ -220,63 +203,108 @@ static int bpf_pid_task_storage_delete_elem(struct bpf_map *map, void *key) } bpf_task_storage_lock(); - err = task_storage_delete(task, map); + err = task_storage_delete(task, map, true); bpf_task_storage_unlock(); out: put_pid(pid); return err; } -/* *gfp_flags* is a hidden argument provided by the verifier */ -BPF_CALL_5(bpf_task_storage_get, struct bpf_map *, map, struct task_struct *, - task, void *, value, u64, flags, gfp_t, gfp_flags) +/* Called by bpf_task_storage_get*() helpers */ +static void *__bpf_task_storage_get(struct bpf_map *map, + struct task_struct *task, void *value, + u64 flags, gfp_t gfp_flags, bool nobusy) { struct bpf_local_storage_data *sdata; - WARN_ON_ONCE(!bpf_rcu_lock_held()); - if (flags & ~(BPF_LOCAL_STORAGE_GET_F_CREATE)) - return (unsigned long)NULL; - - if (!task) - return (unsigned long)NULL; - - if (!bpf_task_storage_trylock()) - return (unsigned long)NULL; - - sdata = task_storage_lookup(task, map, true); + sdata = task_storage_lookup(task, map, nobusy); if (sdata) - goto unlock; + return sdata->data; /* only allocate new storage, when the task is refcounted */ if (refcount_read(&task->usage) && - (flags & BPF_LOCAL_STORAGE_GET_F_CREATE)) + (flags & BPF_LOCAL_STORAGE_GET_F_CREATE) && nobusy) { sdata = bpf_local_storage_update( task, (struct bpf_local_storage_map *)map, value, BPF_NOEXIST, gfp_flags); + return IS_ERR(sdata) ? NULL : sdata->data; + } + + return NULL; +} -unlock: +/* *gfp_flags* is a hidden argument provided by the verifier */ +BPF_CALL_5(bpf_task_storage_get_recur, struct bpf_map *, map, struct task_struct *, + task, void *, value, u64, flags, gfp_t, gfp_flags) +{ + bool nobusy; + void *data; + + WARN_ON_ONCE(!bpf_rcu_lock_held()); + if (flags & ~BPF_LOCAL_STORAGE_GET_F_CREATE || !task) + return (unsigned long)NULL; + + nobusy = bpf_task_storage_trylock(); + data = __bpf_task_storage_get(map, task, value, flags, + gfp_flags, nobusy); + if (nobusy) + bpf_task_storage_unlock(); + return (unsigned long)data; +} + +/* *gfp_flags* is a hidden argument provided by the verifier */ +BPF_CALL_5(bpf_task_storage_get, struct bpf_map *, map, struct task_struct *, + task, void *, value, u64, flags, gfp_t, gfp_flags) +{ + void *data; + + WARN_ON_ONCE(!bpf_rcu_lock_held()); + if (flags & ~BPF_LOCAL_STORAGE_GET_F_CREATE || !task) + return (unsigned long)NULL; + + bpf_task_storage_lock(); + data = __bpf_task_storage_get(map, task, value, flags, + gfp_flags, true); bpf_task_storage_unlock(); - return IS_ERR_OR_NULL(sdata) ? (unsigned long)NULL : - (unsigned long)sdata->data; + return (unsigned long)data; } -BPF_CALL_2(bpf_task_storage_delete, struct bpf_map *, map, struct task_struct *, +BPF_CALL_2(bpf_task_storage_delete_recur, struct bpf_map *, map, struct task_struct *, task) { + bool nobusy; int ret; WARN_ON_ONCE(!bpf_rcu_lock_held()); if (!task) return -EINVAL; - if (!bpf_task_storage_trylock()) - return -EBUSY; + nobusy = bpf_task_storage_trylock(); + /* This helper must only be called from places where the lifetime of the task + * is guaranteed. Either by being refcounted or by being protected + * by an RCU read-side critical section. + */ + ret = task_storage_delete(task, map, nobusy); + if (nobusy) + bpf_task_storage_unlock(); + return ret; +} + +BPF_CALL_2(bpf_task_storage_delete, struct bpf_map *, map, struct task_struct *, + task) +{ + int ret; + + WARN_ON_ONCE(!bpf_rcu_lock_held()); + if (!task) + return -EINVAL; + bpf_task_storage_lock(); /* This helper must only be called from places where the lifetime of the task * is guaranteed. Either by being refcounted or by being protected * by an RCU read-side critical section. */ - ret = task_storage_delete(task, map); + ret = task_storage_delete(task, map, true); bpf_task_storage_unlock(); return ret; } @@ -288,26 +316,15 @@ static int notsupp_get_next_key(struct bpf_map *map, void *key, void *next_key) static struct bpf_map *task_storage_map_alloc(union bpf_attr *attr) { - struct bpf_local_storage_map *smap; - - smap = bpf_local_storage_map_alloc(attr); - if (IS_ERR(smap)) - return ERR_CAST(smap); - - smap->cache_idx = bpf_local_storage_cache_idx_get(&task_cache); - return &smap->map; + return bpf_local_storage_map_alloc(attr, &task_cache); } static void task_storage_map_free(struct bpf_map *map) { - struct bpf_local_storage_map *smap; - - smap = (struct bpf_local_storage_map *)map; - bpf_local_storage_cache_idx_free(&task_cache, smap->cache_idx); - bpf_local_storage_map_free(smap, &bpf_task_storage_busy); + bpf_local_storage_map_free(map, &task_cache, &bpf_task_storage_busy); } -BTF_ID_LIST_SINGLE(task_storage_map_btf_ids, struct, bpf_local_storage_map) +BTF_ID_LIST_GLOBAL_SINGLE(bpf_local_storage_map_btf_id, struct, bpf_local_storage_map) const struct bpf_map_ops task_storage_map_ops = { .map_meta_equal = bpf_map_meta_equal, .map_alloc_check = bpf_local_storage_map_alloc_check, @@ -318,10 +335,21 @@ const struct bpf_map_ops task_storage_map_ops = { .map_update_elem = bpf_pid_task_storage_update_elem, .map_delete_elem = bpf_pid_task_storage_delete_elem, .map_check_btf = bpf_local_storage_map_check_btf, - .map_btf_id = &task_storage_map_btf_ids[0], + .map_btf_id = &bpf_local_storage_map_btf_id[0], .map_owner_storage_ptr = task_storage_ptr, }; +const struct bpf_func_proto bpf_task_storage_get_recur_proto = { + .func = bpf_task_storage_get_recur, + .gpl_only = false, + .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL, + .arg1_type = ARG_CONST_MAP_PTR, + .arg2_type = ARG_PTR_TO_BTF_ID, + .arg2_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK], + .arg3_type = ARG_PTR_TO_MAP_VALUE_OR_NULL, + .arg4_type = ARG_ANYTHING, +}; + const struct bpf_func_proto bpf_task_storage_get_proto = { .func = bpf_task_storage_get, .gpl_only = false, @@ -333,6 +361,15 @@ const struct bpf_func_proto bpf_task_storage_get_proto = { .arg4_type = ARG_ANYTHING, }; +const struct bpf_func_proto bpf_task_storage_delete_recur_proto = { + .func = bpf_task_storage_delete_recur, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_CONST_MAP_PTR, + .arg2_type = ARG_PTR_TO_BTF_ID, + .arg2_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK], +}; + const struct bpf_func_proto bpf_task_storage_delete_proto = { .func = bpf_task_storage_delete, .gpl_only = false, diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 35c07afac924..b7017cae6fd1 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -19,6 +19,7 @@ #include <linux/bpf_verifier.h> #include <linux/btf.h> #include <linux/btf_ids.h> +#include <linux/bpf_lsm.h> #include <linux/skmsg.h> #include <linux/perf_event.h> #include <linux/bsearch.h> @@ -199,11 +200,13 @@ DEFINE_IDR(btf_idr); DEFINE_SPINLOCK(btf_idr_lock); enum btf_kfunc_hook { + BTF_KFUNC_HOOK_COMMON, BTF_KFUNC_HOOK_XDP, BTF_KFUNC_HOOK_TC, BTF_KFUNC_HOOK_STRUCT_OPS, BTF_KFUNC_HOOK_TRACING, BTF_KFUNC_HOOK_SYSCALL, + BTF_KFUNC_HOOK_FMODRET, BTF_KFUNC_HOOK_MAX, }; @@ -237,6 +240,7 @@ struct btf { struct rcu_head rcu; struct btf_kfunc_set_tab *kfunc_set_tab; struct btf_id_dtor_kfunc_tab *dtor_kfunc_tab; + struct btf_struct_metas *struct_meta_tab; /* split BTF support */ struct btf *base_btf; @@ -477,16 +481,6 @@ static bool btf_type_nosize_or_null(const struct btf_type *t) return !t || btf_type_nosize(t); } -static bool __btf_type_is_struct(const struct btf_type *t) -{ - return BTF_INFO_KIND(t->info) == BTF_KIND_STRUCT; -} - -static bool btf_type_is_array(const struct btf_type *t) -{ - return BTF_INFO_KIND(t->info) == BTF_KIND_ARRAY; -} - static bool btf_type_is_datasec(const struct btf_type *t) { return BTF_INFO_KIND(t->info) == BTF_KIND_DATASEC; @@ -1642,8 +1636,30 @@ static void btf_free_dtor_kfunc_tab(struct btf *btf) btf->dtor_kfunc_tab = NULL; } +static void btf_struct_metas_free(struct btf_struct_metas *tab) +{ + int i; + + if (!tab) + return; + for (i = 0; i < tab->cnt; i++) { + btf_record_free(tab->types[i].record); + kfree(tab->types[i].field_offs); + } + kfree(tab); +} + +static void btf_free_struct_meta_tab(struct btf *btf) +{ + struct btf_struct_metas *tab = btf->struct_meta_tab; + + btf_struct_metas_free(tab); + btf->struct_meta_tab = NULL; +} + static void btf_free(struct btf *btf) { + btf_free_struct_meta_tab(btf); btf_free_dtor_kfunc_tab(btf); btf_free_kfunc_set_tab(btf); kvfree(btf->types); @@ -3191,7 +3207,7 @@ static void btf_struct_log(struct btf_verifier_env *env, btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t)); } -enum btf_field_type { +enum btf_field_info_type { BTF_FIELD_SPIN_LOCK, BTF_FIELD_TIMER, BTF_FIELD_KPTR, @@ -3203,18 +3219,28 @@ enum { }; struct btf_field_info { - u32 type_id; + enum btf_field_type type; u32 off; - enum bpf_kptr_type type; + union { + struct { + u32 type_id; + } kptr; + struct { + const char *node_name; + u32 value_btf_id; + } list_head; + }; }; static int btf_find_struct(const struct btf *btf, const struct btf_type *t, - u32 off, int sz, struct btf_field_info *info) + u32 off, int sz, enum btf_field_type field_type, + struct btf_field_info *info) { if (!__btf_type_is_struct(t)) return BTF_FIELD_IGNORE; if (t->size != sz) return BTF_FIELD_IGNORE; + info->type = field_type; info->off = off; return BTF_FIELD_FOUND; } @@ -3222,9 +3248,12 @@ static int btf_find_struct(const struct btf *btf, const struct btf_type *t, static int btf_find_kptr(const struct btf *btf, const struct btf_type *t, u32 off, int sz, struct btf_field_info *info) { - enum bpf_kptr_type type; + enum btf_field_type type; u32 res_id; + /* Permit modifiers on the pointer itself */ + if (btf_type_is_volatile(t)) + t = btf_type_by_id(btf, t->type); /* For PTR, sz is always == 8 */ if (!btf_type_is_ptr(t)) return BTF_FIELD_IGNORE; @@ -3248,28 +3277,135 @@ static int btf_find_kptr(const struct btf *btf, const struct btf_type *t, if (!__btf_type_is_struct(t)) return -EINVAL; - info->type_id = res_id; - info->off = off; info->type = type; + info->off = off; + info->kptr.type_id = res_id; return BTF_FIELD_FOUND; } -static int btf_find_struct_field(const struct btf *btf, const struct btf_type *t, - const char *name, int sz, int align, - enum btf_field_type field_type, +static const char *btf_find_decl_tag_value(const struct btf *btf, + const struct btf_type *pt, + int comp_idx, const char *tag_key) +{ + int i; + + for (i = 1; i < btf_nr_types(btf); i++) { + const struct btf_type *t = btf_type_by_id(btf, i); + int len = strlen(tag_key); + + if (!btf_type_is_decl_tag(t)) + continue; + if (pt != btf_type_by_id(btf, t->type) || + btf_type_decl_tag(t)->component_idx != comp_idx) + continue; + if (strncmp(__btf_name_by_offset(btf, t->name_off), tag_key, len)) + continue; + return __btf_name_by_offset(btf, t->name_off) + len; + } + return NULL; +} + +static int btf_find_list_head(const struct btf *btf, const struct btf_type *pt, + const struct btf_type *t, int comp_idx, + u32 off, int sz, struct btf_field_info *info) +{ + const char *value_type; + const char *list_node; + s32 id; + + if (!__btf_type_is_struct(t)) + return BTF_FIELD_IGNORE; + if (t->size != sz) + return BTF_FIELD_IGNORE; + value_type = btf_find_decl_tag_value(btf, pt, comp_idx, "contains:"); + if (!value_type) + return -EINVAL; + list_node = strstr(value_type, ":"); + if (!list_node) + return -EINVAL; + value_type = kstrndup(value_type, list_node - value_type, GFP_KERNEL | __GFP_NOWARN); + if (!value_type) + return -ENOMEM; + id = btf_find_by_name_kind(btf, value_type, BTF_KIND_STRUCT); + kfree(value_type); + if (id < 0) + return id; + list_node++; + if (str_is_empty(list_node)) + return -EINVAL; + info->type = BPF_LIST_HEAD; + info->off = off; + info->list_head.value_btf_id = id; + info->list_head.node_name = list_node; + return BTF_FIELD_FOUND; +} + +static int btf_get_field_type(const char *name, u32 field_mask, u32 *seen_mask, + int *align, int *sz) +{ + int type = 0; + + if (field_mask & BPF_SPIN_LOCK) { + if (!strcmp(name, "bpf_spin_lock")) { + if (*seen_mask & BPF_SPIN_LOCK) + return -E2BIG; + *seen_mask |= BPF_SPIN_LOCK; + type = BPF_SPIN_LOCK; + goto end; + } + } + if (field_mask & BPF_TIMER) { + if (!strcmp(name, "bpf_timer")) { + if (*seen_mask & BPF_TIMER) + return -E2BIG; + *seen_mask |= BPF_TIMER; + type = BPF_TIMER; + goto end; + } + } + if (field_mask & BPF_LIST_HEAD) { + if (!strcmp(name, "bpf_list_head")) { + type = BPF_LIST_HEAD; + goto end; + } + } + if (field_mask & BPF_LIST_NODE) { + if (!strcmp(name, "bpf_list_node")) { + type = BPF_LIST_NODE; + goto end; + } + } + /* Only return BPF_KPTR when all other types with matchable names fail */ + if (field_mask & BPF_KPTR) { + type = BPF_KPTR_REF; + goto end; + } + return 0; +end: + *sz = btf_field_type_size(type); + *align = btf_field_type_align(type); + return type; +} + +static int btf_find_struct_field(const struct btf *btf, + const struct btf_type *t, u32 field_mask, struct btf_field_info *info, int info_cnt) { + int ret, idx = 0, align, sz, field_type; const struct btf_member *member; struct btf_field_info tmp; - int ret, idx = 0; - u32 i, off; + u32 i, off, seen_mask = 0; for_each_member(i, t, member) { const struct btf_type *member_type = btf_type_by_id(btf, member->type); - if (name && strcmp(__btf_name_by_offset(btf, member_type->name_off), name)) + field_type = btf_get_field_type(__btf_name_by_offset(btf, member_type->name_off), + field_mask, &seen_mask, &align, &sz); + if (field_type == 0) continue; + if (field_type < 0) + return field_type; off = __btf_member_bit_offset(t, member); if (off % 8) @@ -3277,22 +3413,30 @@ static int btf_find_struct_field(const struct btf *btf, const struct btf_type *t return -EINVAL; off /= 8; if (off % align) - return -EINVAL; + continue; switch (field_type) { - case BTF_FIELD_SPIN_LOCK: - case BTF_FIELD_TIMER: - ret = btf_find_struct(btf, member_type, off, sz, + case BPF_SPIN_LOCK: + case BPF_TIMER: + case BPF_LIST_NODE: + ret = btf_find_struct(btf, member_type, off, sz, field_type, idx < info_cnt ? &info[idx] : &tmp); if (ret < 0) return ret; break; - case BTF_FIELD_KPTR: + case BPF_KPTR_UNREF: + case BPF_KPTR_REF: ret = btf_find_kptr(btf, member_type, off, sz, idx < info_cnt ? &info[idx] : &tmp); if (ret < 0) return ret; break; + case BPF_LIST_HEAD: + ret = btf_find_list_head(btf, t, member_type, i, off, sz, + idx < info_cnt ? &info[idx] : &tmp); + if (ret < 0) + return ret; + break; default: return -EFAULT; } @@ -3307,42 +3451,53 @@ static int btf_find_struct_field(const struct btf *btf, const struct btf_type *t } static int btf_find_datasec_var(const struct btf *btf, const struct btf_type *t, - const char *name, int sz, int align, - enum btf_field_type field_type, - struct btf_field_info *info, int info_cnt) + u32 field_mask, struct btf_field_info *info, + int info_cnt) { + int ret, idx = 0, align, sz, field_type; const struct btf_var_secinfo *vsi; struct btf_field_info tmp; - int ret, idx = 0; - u32 i, off; + u32 i, off, seen_mask = 0; for_each_vsi(i, t, vsi) { const struct btf_type *var = btf_type_by_id(btf, vsi->type); const struct btf_type *var_type = btf_type_by_id(btf, var->type); - off = vsi->offset; - - if (name && strcmp(__btf_name_by_offset(btf, var_type->name_off), name)) + field_type = btf_get_field_type(__btf_name_by_offset(btf, var_type->name_off), + field_mask, &seen_mask, &align, &sz); + if (field_type == 0) continue; + if (field_type < 0) + return field_type; + + off = vsi->offset; if (vsi->size != sz) continue; if (off % align) - return -EINVAL; + continue; switch (field_type) { - case BTF_FIELD_SPIN_LOCK: - case BTF_FIELD_TIMER: - ret = btf_find_struct(btf, var_type, off, sz, + case BPF_SPIN_LOCK: + case BPF_TIMER: + case BPF_LIST_NODE: + ret = btf_find_struct(btf, var_type, off, sz, field_type, idx < info_cnt ? &info[idx] : &tmp); if (ret < 0) return ret; break; - case BTF_FIELD_KPTR: + case BPF_KPTR_UNREF: + case BPF_KPTR_REF: ret = btf_find_kptr(btf, var_type, off, sz, idx < info_cnt ? &info[idx] : &tmp); if (ret < 0) return ret; break; + case BPF_LIST_HEAD: + ret = btf_find_list_head(btf, var, var_type, -1, off, sz, + idx < info_cnt ? &info[idx] : &tmp); + if (ret < 0) + return ret; + break; default: return -EFAULT; } @@ -3357,169 +3512,327 @@ static int btf_find_datasec_var(const struct btf *btf, const struct btf_type *t, } static int btf_find_field(const struct btf *btf, const struct btf_type *t, - enum btf_field_type field_type, - struct btf_field_info *info, int info_cnt) + u32 field_mask, struct btf_field_info *info, + int info_cnt) { - const char *name; - int sz, align; - - switch (field_type) { - case BTF_FIELD_SPIN_LOCK: - name = "bpf_spin_lock"; - sz = sizeof(struct bpf_spin_lock); - align = __alignof__(struct bpf_spin_lock); - break; - case BTF_FIELD_TIMER: - name = "bpf_timer"; - sz = sizeof(struct bpf_timer); - align = __alignof__(struct bpf_timer); - break; - case BTF_FIELD_KPTR: - name = NULL; - sz = sizeof(u64); - align = 8; - break; - default: - return -EFAULT; - } - if (__btf_type_is_struct(t)) - return btf_find_struct_field(btf, t, name, sz, align, field_type, info, info_cnt); + return btf_find_struct_field(btf, t, field_mask, info, info_cnt); else if (btf_type_is_datasec(t)) - return btf_find_datasec_var(btf, t, name, sz, align, field_type, info, info_cnt); + return btf_find_datasec_var(btf, t, field_mask, info, info_cnt); return -EINVAL; } -/* find 'struct bpf_spin_lock' in map value. - * return >= 0 offset if found - * and < 0 in case of error - */ -int btf_find_spin_lock(const struct btf *btf, const struct btf_type *t) +static int btf_parse_kptr(const struct btf *btf, struct btf_field *field, + struct btf_field_info *info) { - struct btf_field_info info; + struct module *mod = NULL; + const struct btf_type *t; + struct btf *kernel_btf; int ret; + s32 id; - ret = btf_find_field(btf, t, BTF_FIELD_SPIN_LOCK, &info, 1); - if (ret < 0) - return ret; - if (!ret) - return -ENOENT; - return info.off; + /* Find type in map BTF, and use it to look up the matching type + * in vmlinux or module BTFs, by name and kind. + */ + t = btf_type_by_id(btf, info->kptr.type_id); + id = bpf_find_btf_id(__btf_name_by_offset(btf, t->name_off), BTF_INFO_KIND(t->info), + &kernel_btf); + if (id < 0) + return id; + + /* Find and stash the function pointer for the destruction function that + * needs to be eventually invoked from the map free path. + */ + if (info->type == BPF_KPTR_REF) { + const struct btf_type *dtor_func; + const char *dtor_func_name; + unsigned long addr; + s32 dtor_btf_id; + + /* This call also serves as a whitelist of allowed objects that + * can be used as a referenced pointer and be stored in a map at + * the same time. + */ + dtor_btf_id = btf_find_dtor_kfunc(kernel_btf, id); + if (dtor_btf_id < 0) { + ret = dtor_btf_id; + goto end_btf; + } + + dtor_func = btf_type_by_id(kernel_btf, dtor_btf_id); + if (!dtor_func) { + ret = -ENOENT; + goto end_btf; + } + + if (btf_is_module(kernel_btf)) { + mod = btf_try_get_module(kernel_btf); + if (!mod) { + ret = -ENXIO; + goto end_btf; + } + } + + /* We already verified dtor_func to be btf_type_is_func + * in register_btf_id_dtor_kfuncs. + */ + dtor_func_name = __btf_name_by_offset(kernel_btf, dtor_func->name_off); + addr = kallsyms_lookup_name(dtor_func_name); + if (!addr) { + ret = -EINVAL; + goto end_mod; + } + field->kptr.dtor = (void *)addr; + } + + field->kptr.btf_id = id; + field->kptr.btf = kernel_btf; + field->kptr.module = mod; + return 0; +end_mod: + module_put(mod); +end_btf: + btf_put(kernel_btf); + return ret; } -int btf_find_timer(const struct btf *btf, const struct btf_type *t) +static int btf_parse_list_head(const struct btf *btf, struct btf_field *field, + struct btf_field_info *info) { - struct btf_field_info info; - int ret; + const struct btf_type *t, *n = NULL; + const struct btf_member *member; + u32 offset; + int i; - ret = btf_find_field(btf, t, BTF_FIELD_TIMER, &info, 1); - if (ret < 0) - return ret; - if (!ret) + t = btf_type_by_id(btf, info->list_head.value_btf_id); + /* We've already checked that value_btf_id is a struct type. We + * just need to figure out the offset of the list_node, and + * verify its type. + */ + for_each_member(i, t, member) { + if (strcmp(info->list_head.node_name, __btf_name_by_offset(btf, member->name_off))) + continue; + /* Invalid BTF, two members with same name */ + if (n) + return -EINVAL; + n = btf_type_by_id(btf, member->type); + if (!__btf_type_is_struct(n)) + return -EINVAL; + if (strcmp("bpf_list_node", __btf_name_by_offset(btf, n->name_off))) + return -EINVAL; + offset = __btf_member_bit_offset(n, member); + if (offset % 8) + return -EINVAL; + offset /= 8; + if (offset % __alignof__(struct bpf_list_node)) + return -EINVAL; + + field->list_head.btf = (struct btf *)btf; + field->list_head.value_btf_id = info->list_head.value_btf_id; + field->list_head.node_offset = offset; + } + if (!n) return -ENOENT; - return info.off; + return 0; } -struct bpf_map_value_off *btf_parse_kptrs(const struct btf *btf, - const struct btf_type *t) +struct btf_record *btf_parse_fields(const struct btf *btf, const struct btf_type *t, + u32 field_mask, u32 value_size) { - struct btf_field_info info_arr[BPF_MAP_VALUE_OFF_MAX]; - struct bpf_map_value_off *tab; - struct btf *kernel_btf = NULL; - struct module *mod = NULL; - int ret, i, nr_off; + struct btf_field_info info_arr[BTF_FIELDS_MAX]; + struct btf_record *rec; + u32 next_off = 0; + int ret, i, cnt; - ret = btf_find_field(btf, t, BTF_FIELD_KPTR, info_arr, ARRAY_SIZE(info_arr)); + ret = btf_find_field(btf, t, field_mask, info_arr, ARRAY_SIZE(info_arr)); if (ret < 0) return ERR_PTR(ret); if (!ret) return NULL; - nr_off = ret; - tab = kzalloc(offsetof(struct bpf_map_value_off, off[nr_off]), GFP_KERNEL | __GFP_NOWARN); - if (!tab) + cnt = ret; + /* This needs to be kzalloc to zero out padding and unused fields, see + * comment in btf_record_equal. + */ + rec = kzalloc(offsetof(struct btf_record, fields[cnt]), GFP_KERNEL | __GFP_NOWARN); + if (!rec) return ERR_PTR(-ENOMEM); - for (i = 0; i < nr_off; i++) { - const struct btf_type *t; - s32 id; + rec->spin_lock_off = -EINVAL; + rec->timer_off = -EINVAL; + for (i = 0; i < cnt; i++) { + if (info_arr[i].off + btf_field_type_size(info_arr[i].type) > value_size) { + WARN_ONCE(1, "verifier bug off %d size %d", info_arr[i].off, value_size); + ret = -EFAULT; + goto end; + } + if (info_arr[i].off < next_off) { + ret = -EEXIST; + goto end; + } + next_off = info_arr[i].off + btf_field_type_size(info_arr[i].type); - /* Find type in map BTF, and use it to look up the matching type - * in vmlinux or module BTFs, by name and kind. - */ - t = btf_type_by_id(btf, info_arr[i].type_id); - id = bpf_find_btf_id(__btf_name_by_offset(btf, t->name_off), BTF_INFO_KIND(t->info), - &kernel_btf); - if (id < 0) { - ret = id; + rec->field_mask |= info_arr[i].type; + rec->fields[i].offset = info_arr[i].off; + rec->fields[i].type = info_arr[i].type; + + switch (info_arr[i].type) { + case BPF_SPIN_LOCK: + WARN_ON_ONCE(rec->spin_lock_off >= 0); + /* Cache offset for faster lookup at runtime */ + rec->spin_lock_off = rec->fields[i].offset; + break; + case BPF_TIMER: + WARN_ON_ONCE(rec->timer_off >= 0); + /* Cache offset for faster lookup at runtime */ + rec->timer_off = rec->fields[i].offset; + break; + case BPF_KPTR_UNREF: + case BPF_KPTR_REF: + ret = btf_parse_kptr(btf, &rec->fields[i], &info_arr[i]); + if (ret < 0) + goto end; + break; + case BPF_LIST_HEAD: + ret = btf_parse_list_head(btf, &rec->fields[i], &info_arr[i]); + if (ret < 0) + goto end; + break; + case BPF_LIST_NODE: + break; + default: + ret = -EFAULT; goto end; } + rec->cnt++; + } - /* Find and stash the function pointer for the destruction function that - * needs to be eventually invoked from the map free path. - */ - if (info_arr[i].type == BPF_KPTR_REF) { - const struct btf_type *dtor_func; - const char *dtor_func_name; - unsigned long addr; - s32 dtor_btf_id; - - /* This call also serves as a whitelist of allowed objects that - * can be used as a referenced pointer and be stored in a map at - * the same time. - */ - dtor_btf_id = btf_find_dtor_kfunc(kernel_btf, id); - if (dtor_btf_id < 0) { - ret = dtor_btf_id; - goto end_btf; - } + /* bpf_list_head requires bpf_spin_lock */ + if (btf_record_has_field(rec, BPF_LIST_HEAD) && rec->spin_lock_off < 0) { + ret = -EINVAL; + goto end; + } - dtor_func = btf_type_by_id(kernel_btf, dtor_btf_id); - if (!dtor_func) { - ret = -ENOENT; - goto end_btf; - } + return rec; +end: + btf_record_free(rec); + return ERR_PTR(ret); +} - if (btf_is_module(kernel_btf)) { - mod = btf_try_get_module(kernel_btf); - if (!mod) { - ret = -ENXIO; - goto end_btf; - } - } +int btf_check_and_fixup_fields(const struct btf *btf, struct btf_record *rec) +{ + int i; - /* We already verified dtor_func to be btf_type_is_func - * in register_btf_id_dtor_kfuncs. - */ - dtor_func_name = __btf_name_by_offset(kernel_btf, dtor_func->name_off); - addr = kallsyms_lookup_name(dtor_func_name); - if (!addr) { - ret = -EINVAL; - goto end_mod; - } - tab->off[i].kptr.dtor = (void *)addr; - } + /* There are two owning types, kptr_ref and bpf_list_head. The former + * only supports storing kernel types, which can never store references + * to program allocated local types, atleast not yet. Hence we only need + * to ensure that bpf_list_head ownership does not form cycles. + */ + if (IS_ERR_OR_NULL(rec) || !(rec->field_mask & BPF_LIST_HEAD)) + return 0; + for (i = 0; i < rec->cnt; i++) { + struct btf_struct_meta *meta; + u32 btf_id; + + if (!(rec->fields[i].type & BPF_LIST_HEAD)) + continue; + btf_id = rec->fields[i].list_head.value_btf_id; + meta = btf_find_struct_meta(btf, btf_id); + if (!meta) + return -EFAULT; + rec->fields[i].list_head.value_rec = meta->record; + + if (!(rec->field_mask & BPF_LIST_NODE)) + continue; - tab->off[i].offset = info_arr[i].off; - tab->off[i].type = info_arr[i].type; - tab->off[i].kptr.btf_id = id; - tab->off[i].kptr.btf = kernel_btf; - tab->off[i].kptr.module = mod; + /* We need to ensure ownership acyclicity among all types. The + * proper way to do it would be to topologically sort all BTF + * IDs based on the ownership edges, since there can be multiple + * bpf_list_head in a type. Instead, we use the following + * reasoning: + * + * - A type can only be owned by another type in user BTF if it + * has a bpf_list_node. + * - A type can only _own_ another type in user BTF if it has a + * bpf_list_head. + * + * We ensure that if a type has both bpf_list_head and + * bpf_list_node, its element types cannot be owning types. + * + * To ensure acyclicity: + * + * When A only has bpf_list_head, ownership chain can be: + * A -> B -> C + * Where: + * - B has both bpf_list_head and bpf_list_node. + * - C only has bpf_list_node. + * + * When A has both bpf_list_head and bpf_list_node, some other + * type already owns it in the BTF domain, hence it can not own + * another owning type through any of the bpf_list_head edges. + * A -> B + * Where: + * - B only has bpf_list_node. + */ + if (meta->record->field_mask & BPF_LIST_HEAD) + return -ELOOP; } - tab->nr_off = nr_off; - return tab; -end_mod: - module_put(mod); -end_btf: - btf_put(kernel_btf); -end: - while (i--) { - btf_put(tab->off[i].kptr.btf); - if (tab->off[i].kptr.module) - module_put(tab->off[i].kptr.module); + return 0; +} + +static int btf_field_offs_cmp(const void *_a, const void *_b, const void *priv) +{ + const u32 a = *(const u32 *)_a; + const u32 b = *(const u32 *)_b; + + if (a < b) + return -1; + else if (a > b) + return 1; + return 0; +} + +static void btf_field_offs_swap(void *_a, void *_b, int size, const void *priv) +{ + struct btf_field_offs *foffs = (void *)priv; + u32 *off_base = foffs->field_off; + u32 *a = _a, *b = _b; + u8 *sz_a, *sz_b; + + sz_a = foffs->field_sz + (a - off_base); + sz_b = foffs->field_sz + (b - off_base); + + swap(*a, *b); + swap(*sz_a, *sz_b); +} + +struct btf_field_offs *btf_parse_field_offs(struct btf_record *rec) +{ + struct btf_field_offs *foffs; + u32 i, *off; + u8 *sz; + + BUILD_BUG_ON(ARRAY_SIZE(foffs->field_off) != ARRAY_SIZE(foffs->field_sz)); + if (IS_ERR_OR_NULL(rec)) + return NULL; + + foffs = kzalloc(sizeof(*foffs), GFP_KERNEL | __GFP_NOWARN); + if (!foffs) + return ERR_PTR(-ENOMEM); + + off = foffs->field_off; + sz = foffs->field_sz; + for (i = 0; i < rec->cnt; i++) { + off[i] = rec->fields[i].offset; + sz[i] = btf_field_type_size(rec->fields[i].type); } - kfree(tab); - return ERR_PTR(ret); + foffs->cnt = rec->cnt; + + if (foffs->cnt == 1) + return foffs; + sort_r(foffs->field_off, foffs->cnt, sizeof(foffs->field_off[0]), + btf_field_offs_cmp, btf_field_offs_swap, foffs); + return foffs; } static void __btf_struct_show(const struct btf *btf, const struct btf_type *t, @@ -4468,7 +4781,6 @@ static int btf_func_proto_check(struct btf_verifier_env *env, nr_args--; } - err = 0; for (i = 0; i < nr_args; i++) { const struct btf_type *arg_type; u32 arg_type_id; @@ -4477,8 +4789,12 @@ static int btf_func_proto_check(struct btf_verifier_env *env, arg_type = btf_type_by_id(btf, arg_type_id); if (!arg_type) { btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1); - err = -EINVAL; - break; + return -EINVAL; + } + + if (btf_type_is_resolve_source_only(arg_type)) { + btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1); + return -EINVAL; } if (args[i].name_off && @@ -4486,25 +4802,23 @@ static int btf_func_proto_check(struct btf_verifier_env *env, !btf_name_valid_identifier(btf, args[i].name_off))) { btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1); - err = -EINVAL; - break; + return -EINVAL; } if (btf_type_needs_resolve(arg_type) && !env_type_is_resolved(env, arg_type_id)) { err = btf_resolve(env, arg_type, arg_type_id); if (err) - break; + return err; } if (!btf_type_id_size(btf, &arg_type_id, NULL)) { btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1); - err = -EINVAL; - break; + return -EINVAL; } } - return err; + return 0; } static int btf_func_check(struct btf_verifier_env *env, @@ -4918,6 +5232,119 @@ static int btf_parse_hdr(struct btf_verifier_env *env) return btf_check_sec_info(env, btf_data_size); } +static const char *alloc_obj_fields[] = { + "bpf_spin_lock", + "bpf_list_head", + "bpf_list_node", +}; + +static struct btf_struct_metas * +btf_parse_struct_metas(struct bpf_verifier_log *log, struct btf *btf) +{ + union { + struct btf_id_set set; + struct { + u32 _cnt; + u32 _ids[ARRAY_SIZE(alloc_obj_fields)]; + } _arr; + } aof; + struct btf_struct_metas *tab = NULL; + int i, n, id, ret; + + BUILD_BUG_ON(offsetof(struct btf_id_set, cnt) != 0); + BUILD_BUG_ON(sizeof(struct btf_id_set) != sizeof(u32)); + + memset(&aof, 0, sizeof(aof)); + for (i = 0; i < ARRAY_SIZE(alloc_obj_fields); i++) { + /* Try to find whether this special type exists in user BTF, and + * if so remember its ID so we can easily find it among members + * of structs that we iterate in the next loop. + */ + id = btf_find_by_name_kind(btf, alloc_obj_fields[i], BTF_KIND_STRUCT); + if (id < 0) + continue; + aof.set.ids[aof.set.cnt++] = id; + } + + if (!aof.set.cnt) + return NULL; + sort(&aof.set.ids, aof.set.cnt, sizeof(aof.set.ids[0]), btf_id_cmp_func, NULL); + + n = btf_nr_types(btf); + for (i = 1; i < n; i++) { + struct btf_struct_metas *new_tab; + const struct btf_member *member; + struct btf_field_offs *foffs; + struct btf_struct_meta *type; + struct btf_record *record; + const struct btf_type *t; + int j, tab_cnt; + + t = btf_type_by_id(btf, i); + if (!t) { + ret = -EINVAL; + goto free; + } + if (!__btf_type_is_struct(t)) + continue; + + cond_resched(); + + for_each_member(j, t, member) { + if (btf_id_set_contains(&aof.set, member->type)) + goto parse; + } + continue; + parse: + tab_cnt = tab ? tab->cnt : 0; + new_tab = krealloc(tab, offsetof(struct btf_struct_metas, types[tab_cnt + 1]), + GFP_KERNEL | __GFP_NOWARN); + if (!new_tab) { + ret = -ENOMEM; + goto free; + } + if (!tab) + new_tab->cnt = 0; + tab = new_tab; + + type = &tab->types[tab->cnt]; + type->btf_id = i; + record = btf_parse_fields(btf, t, BPF_SPIN_LOCK | BPF_LIST_HEAD | BPF_LIST_NODE, t->size); + /* The record cannot be unset, treat it as an error if so */ + if (IS_ERR_OR_NULL(record)) { + ret = PTR_ERR_OR_ZERO(record) ?: -EFAULT; + goto free; + } + foffs = btf_parse_field_offs(record); + /* We need the field_offs to be valid for a valid record, + * either both should be set or both should be unset. + */ + if (IS_ERR_OR_NULL(foffs)) { + btf_record_free(record); + ret = -EFAULT; + goto free; + } + type->record = record; + type->field_offs = foffs; + tab->cnt++; + } + return tab; +free: + btf_struct_metas_free(tab); + return ERR_PTR(ret); +} + +struct btf_struct_meta *btf_find_struct_meta(const struct btf *btf, u32 btf_id) +{ + struct btf_struct_metas *tab; + + BUILD_BUG_ON(offsetof(struct btf_struct_meta, btf_id) != 0); + tab = btf->struct_meta_tab; + if (!tab) + return NULL; + return bsearch(&btf_id, tab->types, tab->cnt, sizeof(tab->types[0]), btf_id_cmp_func); +} + static int btf_check_type_tags(struct btf_verifier_env *env, struct btf *btf, int start_id) { @@ -4968,6 +5395,7 @@ static int btf_check_type_tags(struct btf_verifier_env *env, static struct btf *btf_parse(bpfptr_t btf_data, u32 btf_data_size, u32 log_level, char __user *log_ubuf, u32 log_size) { + struct btf_struct_metas *struct_meta_tab; struct btf_verifier_env *env = NULL; struct bpf_verifier_log *log; struct btf *btf = NULL; @@ -5036,15 +5464,34 @@ static struct btf *btf_parse(bpfptr_t btf_data, u32 btf_data_size, if (err) goto errout; + struct_meta_tab = btf_parse_struct_metas(log, btf); + if (IS_ERR(struct_meta_tab)) { + err = PTR_ERR(struct_meta_tab); + goto errout; + } + btf->struct_meta_tab = struct_meta_tab; + + if (struct_meta_tab) { + int i; + + for (i = 0; i < struct_meta_tab->cnt; i++) { + err = btf_check_and_fixup_fields(btf, struct_meta_tab->types[i].record); + if (err < 0) + goto errout_meta; + } + } + if (log->level && bpf_verifier_log_full(log)) { err = -ENOSPC; - goto errout; + goto errout_meta; } btf_verifier_env_free(env); refcount_set(&btf->refcnt, 1); return btf; +errout_meta: + btf_free_struct_meta_tab(btf); errout: btf_verifier_env_free(env); if (btf) @@ -5086,7 +5533,7 @@ static u8 bpf_ctx_convert_map[] = { #undef BPF_MAP_TYPE #undef BPF_LINK_TYPE -static const struct btf_member * +const struct btf_member * btf_get_prog_ctx_type(struct bpf_verifier_log *log, const struct btf *btf, const struct btf_type *t, enum bpf_prog_type prog_type, int arg) @@ -5159,6 +5606,26 @@ static int btf_translate_to_vmlinux(struct bpf_verifier_log *log, return kern_ctx_type->type; } +int get_kern_ctx_btf_id(struct bpf_verifier_log *log, enum bpf_prog_type prog_type) +{ + const struct btf_member *kctx_member; + const struct btf_type *conv_struct; + const struct btf_type *kctx_type; + u32 kctx_type_id; + + conv_struct = bpf_ctx_convert.t; + /* get member for kernel ctx type */ + kctx_member = btf_type_member(conv_struct) + bpf_ctx_convert_map[prog_type] * 2 + 1; + kctx_type_id = kctx_member->type; + kctx_type = btf_type_by_id(btf_vmlinux, kctx_type_id); + if (!btf_type_is_struct(kctx_type)) { + bpf_log(log, "kern ctx type id %u is not a struct\n", kctx_type_id); + return -EINVAL; + } + + return kctx_type_id; +} + BTF_ID_LIST(bpf_ctx_convert_btf_id) BTF_ID(struct, bpf_ctx_convert) @@ -5356,6 +5823,22 @@ static u32 get_ctx_arg_idx(struct btf *btf, const struct btf_type *func_proto, return nr_args + 1; } +static bool prog_args_trusted(const struct bpf_prog *prog) +{ + enum bpf_attach_type atype = prog->expected_attach_type; + + switch (prog->type) { + case BPF_PROG_TYPE_TRACING: + return atype == BPF_TRACE_RAW_TP || atype == BPF_TRACE_ITER; + case BPF_PROG_TYPE_LSM: + return bpf_lsm_is_trusted(prog); + case BPF_PROG_TYPE_STRUCT_OPS: + return true; + default: + return false; + } +} + bool btf_ctx_access(int off, int size, enum bpf_access_type type, const struct bpf_prog *prog, struct bpf_insn_access_aux *info) @@ -5499,6 +5982,9 @@ bool btf_ctx_access(int off, int size, enum bpf_access_type type, } info->reg_type = PTR_TO_BTF_ID; + if (prog_args_trusted(prog)) + info->reg_type |= PTR_TRUSTED; + if (tgt_prog) { enum bpf_prog_type tgt_type; @@ -5765,6 +6251,9 @@ error: /* check __percpu tag */ if (strcmp(tag_value, "percpu") == 0) tmp_flag = MEM_PERCPU; + /* check __rcu tag */ + if (strcmp(tag_value, "rcu") == 0) + tmp_flag = MEM_RCU; } stype = btf_type_skip_modifiers(btf, mtype->type, &id); @@ -5794,20 +6283,50 @@ error: return -EINVAL; } -int btf_struct_access(struct bpf_verifier_log *log, const struct btf *btf, - const struct btf_type *t, int off, int size, - enum bpf_access_type atype __maybe_unused, +int btf_struct_access(struct bpf_verifier_log *log, + const struct bpf_reg_state *reg, + int off, int size, enum bpf_access_type atype __maybe_unused, u32 *next_btf_id, enum bpf_type_flag *flag) { + const struct btf *btf = reg->btf; enum bpf_type_flag tmp_flag = 0; + const struct btf_type *t; + u32 id = reg->btf_id; int err; - u32 id; + while (type_is_alloc(reg->type)) { + struct btf_struct_meta *meta; + struct btf_record *rec; + int i; + + meta = btf_find_struct_meta(btf, id); + if (!meta) + break; + rec = meta->record; + for (i = 0; i < rec->cnt; i++) { + struct btf_field *field = &rec->fields[i]; + u32 offset = field->offset; + if (off < offset + btf_field_type_size(field->type) && offset < off + size) { + bpf_log(log, + "direct access to %s is disallowed\n", + btf_field_type_name(field->type)); + return -EACCES; + } + } + break; + } + + t = btf_type_by_id(btf, id); do { err = btf_struct_walk(log, btf, t, off, size, &id, &tmp_flag); switch (err) { case WALK_PTR: + /* For local types, the destination register cannot + * become a pointer again. + */ + if (type_is_alloc(reg->type)) + return SCALAR_VALUE; /* If we found the pointer or scalar on t+off, * we're done. */ @@ -5842,8 +6361,8 @@ int btf_struct_access(struct bpf_verifier_log *log, const struct btf *btf, * end up with two different module BTFs, but IDs point to the common type in * vmlinux BTF. */ -static bool btf_types_are_same(const struct btf *btf1, u32 id1, - const struct btf *btf2, u32 id2) +bool btf_types_are_same(const struct btf *btf1, u32 id1, + const struct btf *btf2, u32 id2) { if (id1 != id2) return false; @@ -6125,122 +6644,19 @@ int btf_check_type_match(struct bpf_verifier_log *log, const struct bpf_prog *pr return btf_check_func_type_match(log, btf1, t1, btf2, t2); } -static u32 *reg2btf_ids[__BPF_REG_TYPE_MAX] = { -#ifdef CONFIG_NET - [PTR_TO_SOCKET] = &btf_sock_ids[BTF_SOCK_TYPE_SOCK], - [PTR_TO_SOCK_COMMON] = &btf_sock_ids[BTF_SOCK_TYPE_SOCK_COMMON], - [PTR_TO_TCP_SOCK] = &btf_sock_ids[BTF_SOCK_TYPE_TCP], -#endif -}; - -/* Returns true if struct is composed of scalars, 4 levels of nesting allowed */ -static bool __btf_type_is_scalar_struct(struct bpf_verifier_log *log, - const struct btf *btf, - const struct btf_type *t, int rec) -{ - const struct btf_type *member_type; - const struct btf_member *member; - u32 i; - - if (!btf_type_is_struct(t)) - return false; - - for_each_member(i, t, member) { - const struct btf_array *array; - - member_type = btf_type_skip_modifiers(btf, member->type, NULL); - if (btf_type_is_struct(member_type)) { - if (rec >= 3) { - bpf_log(log, "max struct nesting depth exceeded\n"); - return false; - } - if (!__btf_type_is_scalar_struct(log, btf, member_type, rec + 1)) - return false; - continue; - } - if (btf_type_is_array(member_type)) { - array = btf_type_array(member_type); - if (!array->nelems) - return false; - member_type = btf_type_skip_modifiers(btf, array->type, NULL); - if (!btf_type_is_scalar(member_type)) - return false; - continue; - } - if (!btf_type_is_scalar(member_type)) - return false; - } - return true; -} - -static bool is_kfunc_arg_mem_size(const struct btf *btf, - const struct btf_param *arg, - const struct bpf_reg_state *reg) -{ - int len, sfx_len = sizeof("__sz") - 1; - const struct btf_type *t; - const char *param_name; - - t = btf_type_skip_modifiers(btf, arg->type, NULL); - if (!btf_type_is_scalar(t) || reg->type != SCALAR_VALUE) - return false; - - /* In the future, this can be ported to use BTF tagging */ - param_name = btf_name_by_offset(btf, arg->name_off); - if (str_is_empty(param_name)) - return false; - len = strlen(param_name); - if (len < sfx_len) - return false; - param_name += len - sfx_len; - if (strncmp(param_name, "__sz", sfx_len)) - return false; - - return true; -} - -static bool btf_is_kfunc_arg_mem_size(const struct btf *btf, - const struct btf_param *arg, - const struct bpf_reg_state *reg, - const char *name) -{ - int len, target_len = strlen(name); - const struct btf_type *t; - const char *param_name; - - t = btf_type_skip_modifiers(btf, arg->type, NULL); - if (!btf_type_is_scalar(t) || reg->type != SCALAR_VALUE) - return false; - - param_name = btf_name_by_offset(btf, arg->name_off); - if (str_is_empty(param_name)) - return false; - len = strlen(param_name); - if (len != target_len) - return false; - if (strcmp(param_name, name)) - return false; - - return true; -} - static int btf_check_func_arg_match(struct bpf_verifier_env *env, const struct btf *btf, u32 func_id, struct bpf_reg_state *regs, bool ptr_to_mem_ok, - struct bpf_kfunc_arg_meta *kfunc_meta, bool processing_call) { enum bpf_prog_type prog_type = resolve_prog_type(env->prog); - bool rel = false, kptr_get = false, trusted_args = false; - bool sleepable = false; struct bpf_verifier_log *log = &env->log; - u32 i, nargs, ref_id, ref_obj_id = 0; - bool is_kfunc = btf_is_kernel(btf); const char *func_name, *ref_tname; const struct btf_type *t, *ref_t; const struct btf_param *args; - int ref_regno = 0, ret; + u32 i, nargs, ref_id; + int ret; t = btf_type_by_id(btf, func_id); if (!t || !btf_type_is_func(t)) { @@ -6266,14 +6682,6 @@ static int btf_check_func_arg_match(struct bpf_verifier_env *env, return -EINVAL; } - if (is_kfunc && kfunc_meta) { - /* Only kfunc can be release func */ - rel = kfunc_meta->flags & KF_RELEASE; - kptr_get = kfunc_meta->flags & KF_KPTR_GET; - trusted_args = kfunc_meta->flags & KF_TRUSTED_ARGS; - sleepable = kfunc_meta->flags & KF_SLEEPABLE; - } - /* check that BTF function arguments match actual types that the * verifier sees. */ @@ -6281,42 +6689,9 @@ static int btf_check_func_arg_match(struct bpf_verifier_env *env, enum bpf_arg_type arg_type = ARG_DONTCARE; u32 regno = i + 1; struct bpf_reg_state *reg = ®s[regno]; - bool obj_ptr = false; t = btf_type_skip_modifiers(btf, args[i].type, NULL); if (btf_type_is_scalar(t)) { - if (is_kfunc && kfunc_meta) { - bool is_buf_size = false; - - /* check for any const scalar parameter of name "rdonly_buf_size" - * or "rdwr_buf_size" - */ - if (btf_is_kfunc_arg_mem_size(btf, &args[i], reg, - "rdonly_buf_size")) { - kfunc_meta->r0_rdonly = true; - is_buf_size = true; - } else if (btf_is_kfunc_arg_mem_size(btf, &args[i], reg, - "rdwr_buf_size")) - is_buf_size = true; - - if (is_buf_size) { - if (kfunc_meta->r0_size) { - bpf_log(log, "2 or more rdonly/rdwr_buf_size parameters for kfunc"); - return -EINVAL; - } - - if (!tnum_is_const(reg->var_off)) { - bpf_log(log, "R%d is not a const\n", regno); - return -EINVAL; - } - - kfunc_meta->r0_size = reg->var_off.value; - ret = mark_chain_precision(env, regno); - if (ret) - return ret; - } - } - if (reg->type == SCALAR_VALUE) continue; bpf_log(log, "R%d is not a scalar\n", regno); @@ -6329,88 +6704,14 @@ static int btf_check_func_arg_match(struct bpf_verifier_env *env, return -EINVAL; } - /* These register types have special constraints wrt ref_obj_id - * and offset checks. The rest of trusted args don't. - */ - obj_ptr = reg->type == PTR_TO_CTX || reg->type == PTR_TO_BTF_ID || - reg2btf_ids[base_type(reg->type)]; - - /* Check if argument must be a referenced pointer, args + i has - * been verified to be a pointer (after skipping modifiers). - * PTR_TO_CTX is ok without having non-zero ref_obj_id. - */ - if (is_kfunc && trusted_args && (obj_ptr && reg->type != PTR_TO_CTX) && !reg->ref_obj_id) { - bpf_log(log, "R%d must be referenced\n", regno); - return -EINVAL; - } - ref_t = btf_type_skip_modifiers(btf, t->type, &ref_id); ref_tname = btf_name_by_offset(btf, ref_t->name_off); - /* Trusted args have the same offset checks as release arguments */ - if ((trusted_args && obj_ptr) || (rel && reg->ref_obj_id)) - arg_type |= OBJ_RELEASE; ret = check_func_arg_reg_off(env, reg, regno, arg_type); if (ret < 0) return ret; - if (is_kfunc && reg->ref_obj_id) { - /* Ensure only one argument is referenced PTR_TO_BTF_ID */ - if (ref_obj_id) { - bpf_log(log, "verifier internal error: more than one arg with ref_obj_id R%d %u %u\n", - regno, reg->ref_obj_id, ref_obj_id); - return -EFAULT; - } - ref_regno = regno; - ref_obj_id = reg->ref_obj_id; - } - - /* kptr_get is only true for kfunc */ - if (i == 0 && kptr_get) { - struct bpf_map_value_off_desc *off_desc; - - if (reg->type != PTR_TO_MAP_VALUE) { - bpf_log(log, "arg#0 expected pointer to map value\n"); - return -EINVAL; - } - - /* check_func_arg_reg_off allows var_off for - * PTR_TO_MAP_VALUE, but we need fixed offset to find - * off_desc. - */ - if (!tnum_is_const(reg->var_off)) { - bpf_log(log, "arg#0 must have constant offset\n"); - return -EINVAL; - } - - off_desc = bpf_map_kptr_off_contains(reg->map_ptr, reg->off + reg->var_off.value); - if (!off_desc || off_desc->type != BPF_KPTR_REF) { - bpf_log(log, "arg#0 no referenced kptr at map value offset=%llu\n", - reg->off + reg->var_off.value); - return -EINVAL; - } - - if (!btf_type_is_ptr(ref_t)) { - bpf_log(log, "arg#0 BTF type must be a double pointer\n"); - return -EINVAL; - } - - ref_t = btf_type_skip_modifiers(btf, ref_t->type, &ref_id); - ref_tname = btf_name_by_offset(btf, ref_t->name_off); - - if (!btf_type_is_struct(ref_t)) { - bpf_log(log, "kernel function %s args#%d pointer type %s %s is not supported\n", - func_name, i, btf_type_str(ref_t), ref_tname); - return -EINVAL; - } - if (!btf_struct_ids_match(log, btf, ref_id, 0, off_desc->kptr.btf, - off_desc->kptr.btf_id, true)) { - bpf_log(log, "kernel function %s args#%d expected pointer to %s %s\n", - func_name, i, btf_type_str(ref_t), ref_tname); - return -EINVAL; - } - /* rest of the arguments can be anything, like normal kfunc */ - } else if (btf_get_prog_ctx_type(log, btf, t, prog_type, i)) { + if (btf_get_prog_ctx_type(log, btf, t, prog_type, i)) { /* If function expects ctx type in BTF check that caller * is passing PTR_TO_CTX. */ @@ -6420,109 +6721,10 @@ static int btf_check_func_arg_match(struct bpf_verifier_env *env, i, btf_type_str(t)); return -EINVAL; } - } else if (is_kfunc && (reg->type == PTR_TO_BTF_ID || - (reg2btf_ids[base_type(reg->type)] && !type_flag(reg->type)))) { - const struct btf_type *reg_ref_t; - const struct btf *reg_btf; - const char *reg_ref_tname; - u32 reg_ref_id; - - if (!btf_type_is_struct(ref_t)) { - bpf_log(log, "kernel function %s args#%d pointer type %s %s is not supported\n", - func_name, i, btf_type_str(ref_t), - ref_tname); - return -EINVAL; - } - - if (reg->type == PTR_TO_BTF_ID) { - reg_btf = reg->btf; - reg_ref_id = reg->btf_id; - } else { - reg_btf = btf_vmlinux; - reg_ref_id = *reg2btf_ids[base_type(reg->type)]; - } - - reg_ref_t = btf_type_skip_modifiers(reg_btf, reg_ref_id, - ®_ref_id); - reg_ref_tname = btf_name_by_offset(reg_btf, - reg_ref_t->name_off); - if (!btf_struct_ids_match(log, reg_btf, reg_ref_id, - reg->off, btf, ref_id, - trusted_args || (rel && reg->ref_obj_id))) { - bpf_log(log, "kernel function %s args#%d expected pointer to %s %s but R%d has a pointer to %s %s\n", - func_name, i, - btf_type_str(ref_t), ref_tname, - regno, btf_type_str(reg_ref_t), - reg_ref_tname); - return -EINVAL; - } } else if (ptr_to_mem_ok && processing_call) { const struct btf_type *resolve_ret; u32 type_size; - if (is_kfunc) { - bool arg_mem_size = i + 1 < nargs && is_kfunc_arg_mem_size(btf, &args[i + 1], ®s[regno + 1]); - bool arg_dynptr = btf_type_is_struct(ref_t) && - !strcmp(ref_tname, - stringify_struct(bpf_dynptr_kern)); - - /* Permit pointer to mem, but only when argument - * type is pointer to scalar, or struct composed - * (recursively) of scalars. - * When arg_mem_size is true, the pointer can be - * void *. - * Also permit initialized local dynamic pointers. - */ - if (!btf_type_is_scalar(ref_t) && - !__btf_type_is_scalar_struct(log, btf, ref_t, 0) && - !arg_dynptr && - (arg_mem_size ? !btf_type_is_void(ref_t) : 1)) { - bpf_log(log, - "arg#%d pointer type %s %s must point to %sscalar, or struct with scalar\n", - i, btf_type_str(ref_t), ref_tname, arg_mem_size ? "void, " : ""); - return -EINVAL; - } - - if (arg_dynptr) { - if (reg->type != PTR_TO_STACK) { - bpf_log(log, "arg#%d pointer type %s %s not to stack\n", - i, btf_type_str(ref_t), - ref_tname); - return -EINVAL; - } - - if (!is_dynptr_reg_valid_init(env, reg)) { - bpf_log(log, - "arg#%d pointer type %s %s must be valid and initialized\n", - i, btf_type_str(ref_t), - ref_tname); - return -EINVAL; - } - - if (!is_dynptr_type_expected(env, reg, - ARG_PTR_TO_DYNPTR | DYNPTR_TYPE_LOCAL)) { - bpf_log(log, - "arg#%d pointer type %s %s points to unsupported dynamic pointer type\n", - i, btf_type_str(ref_t), - ref_tname); - return -EINVAL; - } - - continue; - } - - /* Check for mem, len pair */ - if (arg_mem_size) { - if (check_kfunc_mem_size_reg(env, ®s[regno + 1], regno + 1)) { - bpf_log(log, "arg#%d arg#%d memory, len pair leads to invalid memory access\n", - i, i + 1); - return -EINVAL; - } - i++; - continue; - } - } - resolve_ret = btf_resolve_size(btf, ref_t, &type_size); if (IS_ERR(resolve_ret)) { bpf_log(log, @@ -6535,36 +6737,13 @@ static int btf_check_func_arg_match(struct bpf_verifier_env *env, if (check_mem_reg(env, reg, regno, type_size)) return -EINVAL; } else { - bpf_log(log, "reg type unsupported for arg#%d %sfunction %s#%d\n", i, - is_kfunc ? "kernel " : "", func_name, func_id); + bpf_log(log, "reg type unsupported for arg#%d function %s#%d\n", i, + func_name, func_id); return -EINVAL; } } - /* Either both are set, or neither */ - WARN_ON_ONCE((ref_obj_id && !ref_regno) || (!ref_obj_id && ref_regno)); - /* We already made sure ref_obj_id is set only for one argument. We do - * allow (!rel && ref_obj_id), so that passing such referenced - * PTR_TO_BTF_ID to other kfuncs works. Note that rel is only true when - * is_kfunc is true. - */ - if (rel && !ref_obj_id) { - bpf_log(log, "release kernel function %s expects refcounted PTR_TO_BTF_ID\n", - func_name); - return -EINVAL; - } - - if (sleepable && !env->prog->aux->sleepable) { - bpf_log(log, "kernel function %s is sleepable but the program is not\n", - func_name); - return -EINVAL; - } - - if (kfunc_meta && ref_obj_id) - kfunc_meta->ref_obj_id = ref_obj_id; - - /* returns argument register number > 0 in case of reference release kfunc */ - return rel ? ref_regno : 0; + return 0; } /* Compare BTF of a function declaration with given bpf_reg_state. @@ -6594,7 +6773,7 @@ int btf_check_subprog_arg_match(struct bpf_verifier_env *env, int subprog, return -EINVAL; is_global = prog->aux->func_info_aux[subprog].linkage == BTF_FUNC_GLOBAL; - err = btf_check_func_arg_match(env, btf, btf_id, regs, is_global, NULL, false); + err = btf_check_func_arg_match(env, btf, btf_id, regs, is_global, false); /* Compiler optimizations can remove arguments from static functions * or mismatched type can be passed into a global function. @@ -6637,7 +6816,7 @@ int btf_check_subprog_call(struct bpf_verifier_env *env, int subprog, return -EINVAL; is_global = prog->aux->func_info_aux[subprog].linkage == BTF_FUNC_GLOBAL; - err = btf_check_func_arg_match(env, btf, btf_id, regs, is_global, NULL, true); + err = btf_check_func_arg_match(env, btf, btf_id, regs, is_global, true); /* Compiler optimizations can remove arguments from static functions * or mismatched type can be passed into a global function. @@ -6648,14 +6827,6 @@ int btf_check_subprog_call(struct bpf_verifier_env *env, int subprog, return err; } -int btf_check_kfunc_arg_match(struct bpf_verifier_env *env, - const struct btf *btf, u32 func_id, - struct bpf_reg_state *regs, - struct bpf_kfunc_arg_meta *meta) -{ - return btf_check_func_arg_match(env, btf, func_id, regs, true, meta, true); -} - /* Convert BTF of a function into bpf_reg_state if possible * Returns: * EFAULT - there is a verifier bug. Abort verification. @@ -7038,23 +7209,6 @@ bool btf_is_module(const struct btf *btf) return btf->kernel_btf && strcmp(btf->name, "vmlinux") != 0; } -static int btf_id_cmp_func(const void *a, const void *b) -{ - const int *pa = a, *pb = b; - - return *pa - *pb; -} - -bool btf_id_set_contains(const struct btf_id_set *set, u32 id) -{ - return bsearch(&id, set->ids, set->cnt, sizeof(u32), btf_id_cmp_func) != NULL; -} - -static void *btf_id_set8_contains(const struct btf_id_set8 *set, u32 id) -{ - return bsearch(&id, set->pairs, set->cnt, sizeof(set->pairs[0]), btf_id_cmp_func); -} - enum { BTF_MODULE_F_LIVE = (1 << 0), }; @@ -7415,6 +7569,8 @@ static u32 *__btf_kfunc_id_set_contains(const struct btf *btf, static int bpf_prog_type_to_kfunc_hook(enum bpf_prog_type prog_type) { switch (prog_type) { + case BPF_PROG_TYPE_UNSPEC: + return BTF_KFUNC_HOOK_COMMON; case BPF_PROG_TYPE_XDP: return BTF_KFUNC_HOOK_XDP; case BPF_PROG_TYPE_SCHED_CLS: @@ -7443,16 +7599,24 @@ u32 *btf_kfunc_id_set_contains(const struct btf *btf, u32 kfunc_btf_id) { enum btf_kfunc_hook hook; + u32 *kfunc_flags; + + kfunc_flags = __btf_kfunc_id_set_contains(btf, BTF_KFUNC_HOOK_COMMON, kfunc_btf_id); + if (kfunc_flags) + return kfunc_flags; hook = bpf_prog_type_to_kfunc_hook(prog_type); return __btf_kfunc_id_set_contains(btf, hook, kfunc_btf_id); } -/* This function must be invoked only from initcalls/module init functions */ -int register_btf_kfunc_id_set(enum bpf_prog_type prog_type, - const struct btf_kfunc_id_set *kset) +u32 *btf_kfunc_is_modify_return(const struct btf *btf, u32 kfunc_btf_id) +{ + return __btf_kfunc_id_set_contains(btf, BTF_KFUNC_HOOK_FMODRET, kfunc_btf_id); +} + +static int __register_btf_kfunc_id_set(enum btf_kfunc_hook hook, + const struct btf_kfunc_id_set *kset) { - enum btf_kfunc_hook hook; struct btf *btf; int ret; @@ -7471,13 +7635,29 @@ int register_btf_kfunc_id_set(enum bpf_prog_type prog_type, if (IS_ERR(btf)) return PTR_ERR(btf); - hook = bpf_prog_type_to_kfunc_hook(prog_type); ret = btf_populate_kfunc_set(btf, hook, kset->set); btf_put(btf); return ret; } + +/* This function must be invoked only from initcalls/module init functions */ +int register_btf_kfunc_id_set(enum bpf_prog_type prog_type, + const struct btf_kfunc_id_set *kset) +{ + enum btf_kfunc_hook hook; + + hook = bpf_prog_type_to_kfunc_hook(prog_type); + return __register_btf_kfunc_id_set(hook, kset); +} EXPORT_SYMBOL_GPL(register_btf_kfunc_id_set); +/* This function must be invoked only from initcalls/module init functions */ +int register_btf_fmodret_id_set(const struct btf_kfunc_id_set *kset) +{ + return __register_btf_kfunc_id_set(BTF_KFUNC_HOOK_FMODRET, kset); +} +EXPORT_SYMBOL_GPL(register_btf_fmodret_id_set); + s32 btf_find_dtor_kfunc(struct btf *btf, u32 btf_id) { struct btf_id_dtor_kfunc_tab *tab = btf->dtor_kfunc_tab; @@ -7602,9 +7782,9 @@ int register_btf_id_dtor_kfuncs(const struct btf_id_dtor_kfunc *dtors, u32 add_c sort(tab->dtors, tab->cnt, sizeof(tab->dtors[0]), btf_id_cmp_func, NULL); - return 0; end: - btf_free_dtor_kfunc_tab(btf); + if (ret) + btf_free_dtor_kfunc_tab(btf); btf_put(btf); return ret; } diff --git a/kernel/bpf/cgroup_iter.c b/kernel/bpf/cgroup_iter.c index 9fcf09f2ef00..06989d278846 100644 --- a/kernel/bpf/cgroup_iter.c +++ b/kernel/bpf/cgroup_iter.c @@ -157,23 +157,37 @@ static const struct seq_operations cgroup_iter_seq_ops = { .show = cgroup_iter_seq_show, }; -BTF_ID_LIST_SINGLE(bpf_cgroup_btf_id, struct, cgroup) +BTF_ID_LIST_GLOBAL_SINGLE(bpf_cgroup_btf_id, struct, cgroup) static int cgroup_iter_seq_init(void *priv, struct bpf_iter_aux_info *aux) { struct cgroup_iter_priv *p = (struct cgroup_iter_priv *)priv; struct cgroup *cgrp = aux->cgroup.start; + /* bpf_iter_attach_cgroup() has already acquired an extra reference + * for the start cgroup, but the reference may be released after + * cgroup_iter_seq_init(), so acquire another reference for the + * start cgroup. + */ p->start_css = &cgrp->self; + css_get(p->start_css); p->terminate = false; p->visited_all = false; p->order = aux->cgroup.order; return 0; } +static void cgroup_iter_seq_fini(void *priv) +{ + struct cgroup_iter_priv *p = (struct cgroup_iter_priv *)priv; + + css_put(p->start_css); +} + static const struct bpf_iter_seq_info cgroup_iter_seq_info = { .seq_ops = &cgroup_iter_seq_ops, .init_seq_private = cgroup_iter_seq_init, + .fini_seq_private = cgroup_iter_seq_fini, .seq_priv_size = sizeof(struct cgroup_iter_priv), }; diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 38159f39e2af..ba3fff17e2f9 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -34,6 +34,7 @@ #include <linux/log2.h> #include <linux/bpf_verifier.h> #include <linux/nodemask.h> +#include <linux/bpf_mem_alloc.h> #include <asm/barrier.h> #include <asm/unaligned.h> @@ -60,6 +61,9 @@ #define CTX regs[BPF_REG_CTX] #define IMM insn->imm +struct bpf_mem_alloc bpf_global_ma; +bool bpf_global_ma_set; + /* No hurry in this branch * * Exported for the bpf jit load helper. @@ -864,8 +868,7 @@ static struct bpf_prog_pack *alloc_new_pack(bpf_jit_fill_hole_t bpf_fill_ill_ins list_add_tail(&pack->list, &pack_list); set_vm_flush_reset_perms(pack->ptr); - set_memory_ro((unsigned long)pack->ptr, BPF_PROG_PACK_SIZE / PAGE_SIZE); - set_memory_x((unsigned long)pack->ptr, BPF_PROG_PACK_SIZE / PAGE_SIZE); + set_memory_rox((unsigned long)pack->ptr, BPF_PROG_PACK_SIZE / PAGE_SIZE); return pack; } @@ -883,8 +886,7 @@ void *bpf_prog_pack_alloc(u32 size, bpf_jit_fill_hole_t bpf_fill_ill_insns) if (ptr) { bpf_fill_ill_insns(ptr, size); set_vm_flush_reset_perms(ptr); - set_memory_ro((unsigned long)ptr, size / PAGE_SIZE); - set_memory_x((unsigned long)ptr, size / PAGE_SIZE); + set_memory_rox((unsigned long)ptr, size / PAGE_SIZE); } goto out; } @@ -2088,6 +2090,7 @@ static unsigned int __bpf_prog_ret0_warn(const void *ctx, bool bpf_prog_map_compatible(struct bpf_map *map, const struct bpf_prog *fp) { + enum bpf_prog_type prog_type = resolve_prog_type(fp); bool ret; if (fp->kprobe_override) @@ -2098,12 +2101,12 @@ bool bpf_prog_map_compatible(struct bpf_map *map, /* There's no owner yet where we could check for * compatibility. */ - map->owner.type = fp->type; + map->owner.type = prog_type; map->owner.jited = fp->jited; map->owner.xdp_has_frags = fp->aux->xdp_has_frags; ret = true; } else { - ret = map->owner.type == fp->type && + ret = map->owner.type == prog_type && map->owner.jited == fp->jited && map->owner.xdp_has_frags == fp->aux->xdp_has_frags; } @@ -2251,8 +2254,14 @@ static void __bpf_prog_array_free_sleepable_cb(struct rcu_head *rcu) { struct bpf_prog_array *progs; + /* If RCU Tasks Trace grace period implies RCU grace period, there is + * no need to call kfree_rcu(), just call kfree() directly. + */ progs = container_of(rcu, struct bpf_prog_array, rcu); - kfree_rcu(progs, rcu); + if (rcu_trace_implies_rcu_gp()) + kfree(progs); + else + kfree_rcu(progs, rcu); } void bpf_prog_array_free_sleepable(struct bpf_prog_array *progs) @@ -2740,6 +2749,18 @@ int __weak bpf_arch_text_invalidate(void *dst, size_t len) return -ENOTSUPP; } +#ifdef CONFIG_BPF_SYSCALL +static int __init bpf_global_ma_init(void) +{ + int ret; + + ret = bpf_mem_alloc_init(&bpf_global_ma, 0, false); + bpf_global_ma_set = !ret; + return ret; +} +late_initcall(bpf_global_ma_init); +#endif + DEFINE_STATIC_KEY_FALSE(bpf_stats_enabled_key); EXPORT_SYMBOL(bpf_stats_enabled_key); diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c index b5ba34ddd4b6..e0b2d016f0bf 100644 --- a/kernel/bpf/cpumap.c +++ b/kernel/bpf/cpumap.c @@ -4,13 +4,16 @@ * Copyright (c) 2017 Jesper Dangaard Brouer, Red Hat Inc. */ -/* The 'cpumap' is primarily used as a backend map for XDP BPF helper +/** + * DOC: cpu map + * The 'cpumap' is primarily used as a backend map for XDP BPF helper * call bpf_redirect_map() and XDP_REDIRECT action, like 'devmap'. * - * Unlike devmap which redirects XDP frames out another NIC device, + * Unlike devmap which redirects XDP frames out to another NIC device, * this map type redirects raw XDP frames to another CPU. The remote * CPU will do SKB-allocation and call the normal network stack. - * + */ +/* * This is a scalability and isolation mechanism, that allow * separating the early driver network XDP layer, from the rest of the * netstack, and assigning dedicated CPUs for this stage. This @@ -85,7 +88,6 @@ static struct bpf_map *cpu_map_alloc(union bpf_attr *attr) { u32 value_size = attr->value_size; struct bpf_cpu_map *cmap; - int err = -ENOMEM; if (!bpf_capable()) return ERR_PTR(-EPERM); @@ -97,29 +99,26 @@ static struct bpf_map *cpu_map_alloc(union bpf_attr *attr) attr->map_flags & ~BPF_F_NUMA_NODE) return ERR_PTR(-EINVAL); + /* Pre-limit array size based on NR_CPUS, not final CPU check */ + if (attr->max_entries > NR_CPUS) + return ERR_PTR(-E2BIG); + cmap = bpf_map_area_alloc(sizeof(*cmap), NUMA_NO_NODE); if (!cmap) return ERR_PTR(-ENOMEM); bpf_map_init_from_attr(&cmap->map, attr); - /* Pre-limit array size based on NR_CPUS, not final CPU check */ - if (cmap->map.max_entries > NR_CPUS) { - err = -E2BIG; - goto free_cmap; - } - /* Alloc array for possible remote "destination" CPUs */ cmap->cpu_map = bpf_map_area_alloc(cmap->map.max_entries * sizeof(struct bpf_cpu_map_entry *), cmap->map.numa_node); - if (!cmap->cpu_map) - goto free_cmap; + if (!cmap->cpu_map) { + bpf_map_area_free(cmap); + return ERR_PTR(-ENOMEM); + } return &cmap->map; -free_cmap: - bpf_map_area_free(cmap); - return ERR_PTR(err); } static void get_cpu_map_entry(struct bpf_cpu_map_entry *rcpu) @@ -668,9 +667,9 @@ static int cpu_map_get_next_key(struct bpf_map *map, void *key, void *next_key) return 0; } -static int cpu_map_redirect(struct bpf_map *map, u32 ifindex, u64 flags) +static int cpu_map_redirect(struct bpf_map *map, u64 index, u64 flags) { - return __bpf_xdp_redirect_map(map, ifindex, flags, 0, + return __bpf_xdp_redirect_map(map, index, flags, 0, __cpu_map_lookup_elem); } diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c index f9a87dcc5535..d01e4c55b376 100644 --- a/kernel/bpf/devmap.c +++ b/kernel/bpf/devmap.c @@ -992,14 +992,14 @@ static int dev_map_hash_update_elem(struct bpf_map *map, void *key, void *value, map, key, value, map_flags); } -static int dev_map_redirect(struct bpf_map *map, u32 ifindex, u64 flags) +static int dev_map_redirect(struct bpf_map *map, u64 ifindex, u64 flags) { return __bpf_xdp_redirect_map(map, ifindex, flags, BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS, __dev_map_lookup_elem); } -static int dev_hash_map_redirect(struct bpf_map *map, u32 ifindex, u64 flags) +static int dev_hash_map_redirect(struct bpf_map *map, u64 ifindex, u64 flags) { return __bpf_xdp_redirect_map(map, ifindex, flags, BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS, diff --git a/kernel/bpf/dispatcher.c b/kernel/bpf/dispatcher.c index c19719f48ce0..fa3e9225aedc 100644 --- a/kernel/bpf/dispatcher.c +++ b/kernel/bpf/dispatcher.c @@ -125,6 +125,11 @@ static void bpf_dispatcher_update(struct bpf_dispatcher *d, int prev_num_progs) __BPF_DISPATCHER_UPDATE(d, new ?: (void *)&bpf_dispatcher_nop_func); + /* Make sure all the callers executing the previous/old half of the + * image leave it, so following update call can modify it safely. + */ + synchronize_rcu(); + if (new) d->image_off = noff; } diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c index f39ee3e05589..66bded144377 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -152,7 +152,7 @@ static inline int htab_lock_bucket(const struct bpf_htab *htab, { unsigned long flags; - hash = hash & HASHTAB_MAP_LOCK_MASK; + hash = hash & min_t(u32, HASHTAB_MAP_LOCK_MASK, htab->n_buckets - 1); preempt_disable(); if (unlikely(__this_cpu_inc_return(*(htab->map_locked[hash])) != 1)) { @@ -171,7 +171,7 @@ static inline void htab_unlock_bucket(const struct bpf_htab *htab, struct bucket *b, u32 hash, unsigned long flags) { - hash = hash & HASHTAB_MAP_LOCK_MASK; + hash = hash & min_t(u32, HASHTAB_MAP_LOCK_MASK, htab->n_buckets - 1); raw_spin_unlock_irqrestore(&b->raw_lock, flags); __this_cpu_dec(*(htab->map_locked[hash])); preempt_enable(); @@ -222,7 +222,7 @@ static void htab_free_prealloced_timers(struct bpf_htab *htab) u32 num_entries = htab->map.max_entries; int i; - if (!map_value_has_timer(&htab->map)) + if (!btf_record_has_field(htab->map.record, BPF_TIMER)) return; if (htab_has_extra_elems(htab)) num_entries += num_possible_cpus(); @@ -231,28 +231,25 @@ static void htab_free_prealloced_timers(struct bpf_htab *htab) struct htab_elem *elem; elem = get_htab_elem(htab, i); - bpf_timer_cancel_and_free(elem->key + - round_up(htab->map.key_size, 8) + - htab->map.timer_off); + bpf_obj_free_timer(htab->map.record, elem->key + round_up(htab->map.key_size, 8)); cond_resched(); } } -static void htab_free_prealloced_kptrs(struct bpf_htab *htab) +static void htab_free_prealloced_fields(struct bpf_htab *htab) { u32 num_entries = htab->map.max_entries; int i; - if (!map_value_has_kptrs(&htab->map)) + if (IS_ERR_OR_NULL(htab->map.record)) return; if (htab_has_extra_elems(htab)) num_entries += num_possible_cpus(); - for (i = 0; i < num_entries; i++) { struct htab_elem *elem; elem = get_htab_elem(htab, i); - bpf_map_free_kptrs(&htab->map, elem->key + round_up(htab->map.key_size, 8)); + bpf_obj_free_fields(htab->map.record, elem->key + round_up(htab->map.key_size, 8)); cond_resched(); } } @@ -764,10 +761,7 @@ static void check_and_free_fields(struct bpf_htab *htab, { void *map_value = elem->key + round_up(htab->map.key_size, 8); - if (map_value_has_timer(&htab->map)) - bpf_timer_cancel_and_free(map_value + htab->map.timer_off); - if (map_value_has_kptrs(&htab->map)) - bpf_map_free_kptrs(&htab->map, map_value); + bpf_obj_free_fields(htab->map.record, map_value); } /* It is called from the bpf_lru_list when the LRU needs to delete @@ -1091,7 +1085,7 @@ static int htab_map_update_elem(struct bpf_map *map, void *key, void *value, head = &b->head; if (unlikely(map_flags & BPF_F_LOCK)) { - if (unlikely(!map_value_has_spin_lock(map))) + if (unlikely(!btf_record_has_field(map->record, BPF_SPIN_LOCK))) return -EINVAL; /* find an element without taking the bucket lock */ l_old = lookup_nulls_elem_raw(head, hash, key, key_size, @@ -1474,12 +1468,8 @@ static void htab_free_malloced_timers(struct bpf_htab *htab) struct htab_elem *l; hlist_nulls_for_each_entry(l, n, head, hash_node) { - /* We don't reset or free kptr on uref dropping to zero, - * hence just free timer. - */ - bpf_timer_cancel_and_free(l->key + - round_up(htab->map.key_size, 8) + - htab->map.timer_off); + /* We only free timer on uref dropping to zero */ + bpf_obj_free_timer(htab->map.record, l->key + round_up(htab->map.key_size, 8)); } cond_resched_rcu(); } @@ -1490,8 +1480,8 @@ static void htab_map_free_timers(struct bpf_map *map) { struct bpf_htab *htab = container_of(map, struct bpf_htab, map); - /* We don't reset or free kptr on uref dropping to zero. */ - if (!map_value_has_timer(&htab->map)) + /* We only free timer on uref dropping to zero */ + if (!btf_record_has_field(htab->map.record, BPF_TIMER)) return; if (!htab_is_prealloc(htab)) htab_free_malloced_timers(htab); @@ -1517,11 +1507,10 @@ static void htab_map_free(struct bpf_map *map) if (!htab_is_prealloc(htab)) { delete_all_elements(htab); } else { - htab_free_prealloced_kptrs(htab); + htab_free_prealloced_fields(htab); prealloc_destroy(htab); } - bpf_map_free_kptr_off_tab(map); free_percpu(htab->extra_elems); bpf_map_area_free(htab->buckets); bpf_mem_alloc_destroy(&htab->pcpu_ma); @@ -1675,7 +1664,7 @@ __htab_map_lookup_and_delete_batch(struct bpf_map *map, elem_map_flags = attr->batch.elem_flags; if ((elem_map_flags & ~BPF_F_LOCK) || - ((elem_map_flags & BPF_F_LOCK) && !map_value_has_spin_lock(map))) + ((elem_map_flags & BPF_F_LOCK) && !btf_record_has_field(map->record, BPF_SPIN_LOCK))) return -EINVAL; map_flags = attr->batch.flags; diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index a6b04faed282..af30c6cbd65d 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -4,6 +4,7 @@ #include <linux/bpf.h> #include <linux/btf.h> #include <linux/bpf-cgroup.h> +#include <linux/cgroup.h> #include <linux/rcupdate.h> #include <linux/random.h> #include <linux/smp.h> @@ -19,6 +20,7 @@ #include <linux/proc_ns.h> #include <linux/security.h> #include <linux/btf_ids.h> +#include <linux/bpf_mem_alloc.h> #include "../../lib/kstrtox.h" @@ -336,6 +338,7 @@ const struct bpf_func_proto bpf_spin_lock_proto = { .gpl_only = false, .ret_type = RET_VOID, .arg1_type = ARG_PTR_TO_SPIN_LOCK, + .arg1_btf_id = BPF_PTR_POISON, }; static inline void __bpf_spin_unlock_irqrestore(struct bpf_spin_lock *lock) @@ -358,6 +361,7 @@ const struct bpf_func_proto bpf_spin_unlock_proto = { .gpl_only = false, .ret_type = RET_VOID, .arg1_type = ARG_PTR_TO_SPIN_LOCK, + .arg1_btf_id = BPF_PTR_POISON, }; void copy_map_value_locked(struct bpf_map *map, void *dst, void *src, @@ -366,9 +370,9 @@ void copy_map_value_locked(struct bpf_map *map, void *dst, void *src, struct bpf_spin_lock *lock; if (lock_src) - lock = src + map->spin_lock_off; + lock = src + map->record->spin_lock_off; else - lock = dst + map->spin_lock_off; + lock = dst + map->record->spin_lock_off; preempt_disable(); __bpf_spin_lock_irqsave(lock); copy_map_value(map, dst, src); @@ -657,6 +661,7 @@ BPF_CALL_3(bpf_copy_from_user, void *, dst, u32, size, const struct bpf_func_proto bpf_copy_from_user_proto = { .func = bpf_copy_from_user, .gpl_only = false, + .might_sleep = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_UNINIT_MEM, .arg2_type = ARG_CONST_SIZE_OR_ZERO, @@ -687,6 +692,7 @@ BPF_CALL_5(bpf_copy_from_user_task, void *, dst, u32, size, const struct bpf_func_proto bpf_copy_from_user_task_proto = { .func = bpf_copy_from_user_task, .gpl_only = true, + .might_sleep = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_UNINIT_MEM, .arg2_type = ARG_CONST_SIZE_OR_ZERO, @@ -1169,7 +1175,7 @@ BPF_CALL_3(bpf_timer_init, struct bpf_timer_kern *, timer, struct bpf_map *, map ret = -ENOMEM; goto out; } - t->value = (void *)timer - map->timer_off; + t->value = (void *)timer - map->record->timer_off; t->map = map; t->prog = NULL; rcu_assign_pointer(t->callback_fn, NULL); @@ -1398,7 +1404,7 @@ static const struct bpf_func_proto bpf_kptr_xchg_proto = { #define DYNPTR_SIZE_MASK 0xFFFFFF #define DYNPTR_RDONLY_BIT BIT(31) -static bool bpf_dynptr_is_rdonly(struct bpf_dynptr_kern *ptr) +static bool bpf_dynptr_is_rdonly(const struct bpf_dynptr_kern *ptr) { return ptr->size & DYNPTR_RDONLY_BIT; } @@ -1408,7 +1414,7 @@ static void bpf_dynptr_set_type(struct bpf_dynptr_kern *ptr, enum bpf_dynptr_typ ptr->size |= type << DYNPTR_TYPE_SHIFT; } -u32 bpf_dynptr_get_size(struct bpf_dynptr_kern *ptr) +u32 bpf_dynptr_get_size(const struct bpf_dynptr_kern *ptr) { return ptr->size & DYNPTR_SIZE_MASK; } @@ -1432,7 +1438,7 @@ void bpf_dynptr_set_null(struct bpf_dynptr_kern *ptr) memset(ptr, 0, sizeof(*ptr)); } -static int bpf_dynptr_check_off_len(struct bpf_dynptr_kern *ptr, u32 offset, u32 len) +static int bpf_dynptr_check_off_len(const struct bpf_dynptr_kern *ptr, u32 offset, u32 len) { u32 size = bpf_dynptr_get_size(ptr); @@ -1477,7 +1483,7 @@ static const struct bpf_func_proto bpf_dynptr_from_mem_proto = { .arg4_type = ARG_PTR_TO_DYNPTR | DYNPTR_TYPE_LOCAL | MEM_UNINIT, }; -BPF_CALL_5(bpf_dynptr_read, void *, dst, u32, len, struct bpf_dynptr_kern *, src, +BPF_CALL_5(bpf_dynptr_read, void *, dst, u32, len, const struct bpf_dynptr_kern *, src, u32, offset, u64, flags) { int err; @@ -1489,7 +1495,11 @@ BPF_CALL_5(bpf_dynptr_read, void *, dst, u32, len, struct bpf_dynptr_kern *, src if (err) return err; - memcpy(dst, src->data + src->offset + offset, len); + /* Source and destination may possibly overlap, hence use memmove to + * copy the data. E.g. bpf_dynptr_from_mem may create two dynptr + * pointing to overlapping PTR_TO_MAP_VALUE regions. + */ + memmove(dst, src->data + src->offset + offset, len); return 0; } @@ -1500,12 +1510,12 @@ static const struct bpf_func_proto bpf_dynptr_read_proto = { .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_UNINIT_MEM, .arg2_type = ARG_CONST_SIZE_OR_ZERO, - .arg3_type = ARG_PTR_TO_DYNPTR, + .arg3_type = ARG_PTR_TO_DYNPTR | MEM_RDONLY, .arg4_type = ARG_ANYTHING, .arg5_type = ARG_ANYTHING, }; -BPF_CALL_5(bpf_dynptr_write, struct bpf_dynptr_kern *, dst, u32, offset, void *, src, +BPF_CALL_5(bpf_dynptr_write, const struct bpf_dynptr_kern *, dst, u32, offset, void *, src, u32, len, u64, flags) { int err; @@ -1517,7 +1527,11 @@ BPF_CALL_5(bpf_dynptr_write, struct bpf_dynptr_kern *, dst, u32, offset, void *, if (err) return err; - memcpy(dst->data + dst->offset + offset, src, len); + /* Source and destination may possibly overlap, hence use memmove to + * copy the data. E.g. bpf_dynptr_from_mem may create two dynptr + * pointing to overlapping PTR_TO_MAP_VALUE regions. + */ + memmove(dst->data + dst->offset + offset, src, len); return 0; } @@ -1526,14 +1540,14 @@ static const struct bpf_func_proto bpf_dynptr_write_proto = { .func = bpf_dynptr_write, .gpl_only = false, .ret_type = RET_INTEGER, - .arg1_type = ARG_PTR_TO_DYNPTR, + .arg1_type = ARG_PTR_TO_DYNPTR | MEM_RDONLY, .arg2_type = ARG_ANYTHING, .arg3_type = ARG_PTR_TO_MEM | MEM_RDONLY, .arg4_type = ARG_CONST_SIZE_OR_ZERO, .arg5_type = ARG_ANYTHING, }; -BPF_CALL_3(bpf_dynptr_data, struct bpf_dynptr_kern *, ptr, u32, offset, u32, len) +BPF_CALL_3(bpf_dynptr_data, const struct bpf_dynptr_kern *, ptr, u32, offset, u32, len) { int err; @@ -1554,7 +1568,7 @@ static const struct bpf_func_proto bpf_dynptr_data_proto = { .func = bpf_dynptr_data, .gpl_only = false, .ret_type = RET_PTR_TO_DYNPTR_MEM_OR_NULL, - .arg1_type = ARG_PTR_TO_DYNPTR, + .arg1_type = ARG_PTR_TO_DYNPTR | MEM_RDONLY, .arg2_type = ARG_ANYTHING, .arg3_type = ARG_CONST_ALLOC_SIZE_OR_ZERO, }; @@ -1663,6 +1677,12 @@ bpf_base_func_proto(enum bpf_func_id func_id) return &bpf_dynptr_write_proto; case BPF_FUNC_dynptr_data: return &bpf_dynptr_data_proto; +#ifdef CONFIG_CGROUPS + case BPF_FUNC_cgrp_storage_get: + return &bpf_cgrp_storage_get_proto; + case BPF_FUNC_cgrp_storage_delete: + return &bpf_cgrp_storage_delete_proto; +#endif default: break; } @@ -1700,20 +1720,401 @@ bpf_base_func_proto(enum bpf_func_id func_id) } } -BTF_SET8_START(tracing_btf_ids) +void bpf_list_head_free(const struct btf_field *field, void *list_head, + struct bpf_spin_lock *spin_lock) +{ + struct list_head *head = list_head, *orig_head = list_head; + + BUILD_BUG_ON(sizeof(struct list_head) > sizeof(struct bpf_list_head)); + BUILD_BUG_ON(__alignof__(struct list_head) > __alignof__(struct bpf_list_head)); + + /* Do the actual list draining outside the lock to not hold the lock for + * too long, and also prevent deadlocks if tracing programs end up + * executing on entry/exit of functions called inside the critical + * section, and end up doing map ops that call bpf_list_head_free for + * the same map value again. + */ + __bpf_spin_lock_irqsave(spin_lock); + if (!head->next || list_empty(head)) + goto unlock; + head = head->next; +unlock: + INIT_LIST_HEAD(orig_head); + __bpf_spin_unlock_irqrestore(spin_lock); + + while (head != orig_head) { + void *obj = head; + + obj -= field->list_head.node_offset; + head = head->next; + /* The contained type can also have resources, including a + * bpf_list_head which needs to be freed. + */ + bpf_obj_free_fields(field->list_head.value_rec, obj); + /* bpf_mem_free requires migrate_disable(), since we can be + * called from map free path as well apart from BPF program (as + * part of map ops doing bpf_obj_free_fields). + */ + migrate_disable(); + bpf_mem_free(&bpf_global_ma, obj); + migrate_enable(); + } +} + +__diag_push(); +__diag_ignore_all("-Wmissing-prototypes", + "Global functions as their definitions will be in vmlinux BTF"); + +void *bpf_obj_new_impl(u64 local_type_id__k, void *meta__ign) +{ + struct btf_struct_meta *meta = meta__ign; + u64 size = local_type_id__k; + void *p; + + p = bpf_mem_alloc(&bpf_global_ma, size); + if (!p) + return NULL; + if (meta) + bpf_obj_init(meta->field_offs, p); + return p; +} + +void bpf_obj_drop_impl(void *p__alloc, void *meta__ign) +{ + struct btf_struct_meta *meta = meta__ign; + void *p = p__alloc; + + if (meta) + bpf_obj_free_fields(meta->record, p); + bpf_mem_free(&bpf_global_ma, p); +} + +static void __bpf_list_add(struct bpf_list_node *node, struct bpf_list_head *head, bool tail) +{ + struct list_head *n = (void *)node, *h = (void *)head; + + if (unlikely(!h->next)) + INIT_LIST_HEAD(h); + if (unlikely(!n->next)) + INIT_LIST_HEAD(n); + tail ? list_add_tail(n, h) : list_add(n, h); +} + +void bpf_list_push_front(struct bpf_list_head *head, struct bpf_list_node *node) +{ + return __bpf_list_add(node, head, false); +} + +void bpf_list_push_back(struct bpf_list_head *head, struct bpf_list_node *node) +{ + return __bpf_list_add(node, head, true); +} + +static struct bpf_list_node *__bpf_list_del(struct bpf_list_head *head, bool tail) +{ + struct list_head *n, *h = (void *)head; + + if (unlikely(!h->next)) + INIT_LIST_HEAD(h); + if (list_empty(h)) + return NULL; + n = tail ? h->prev : h->next; + list_del_init(n); + return (struct bpf_list_node *)n; +} + +struct bpf_list_node *bpf_list_pop_front(struct bpf_list_head *head) +{ + return __bpf_list_del(head, false); +} + +struct bpf_list_node *bpf_list_pop_back(struct bpf_list_head *head) +{ + return __bpf_list_del(head, true); +} + +/** + * bpf_task_acquire - Acquire a reference to a task. A task acquired by this + * kfunc which is not stored in a map as a kptr, must be released by calling + * bpf_task_release(). + * @p: The task on which a reference is being acquired. + */ +struct task_struct *bpf_task_acquire(struct task_struct *p) +{ + return get_task_struct(p); +} + +/** + * bpf_task_acquire_not_zero - Acquire a reference to a rcu task object. A task + * acquired by this kfunc which is not stored in a map as a kptr, must be + * released by calling bpf_task_release(). + * @p: The task on which a reference is being acquired. + */ +struct task_struct *bpf_task_acquire_not_zero(struct task_struct *p) +{ + /* For the time being this function returns NULL, as it's not currently + * possible to safely acquire a reference to a task with RCU protection + * using get_task_struct() and put_task_struct(). This is due to the + * slightly odd mechanics of p->rcu_users, and how task RCU protection + * works. + * + * A struct task_struct is refcounted by two different refcount_t + * fields: + * + * 1. p->usage: The "true" refcount field which tracks a task's + * lifetime. The task is freed as soon as this + * refcount drops to 0. + * + * 2. p->rcu_users: An "RCU users" refcount field which is statically + * initialized to 2, and is co-located in a union with + * a struct rcu_head field (p->rcu). p->rcu_users + * essentially encapsulates a single p->usage + * refcount, and when p->rcu_users goes to 0, an RCU + * callback is scheduled on the struct rcu_head which + * decrements the p->usage refcount. + * + * There are two important implications to this task refcounting logic + * described above. The first is that + * refcount_inc_not_zero(&p->rcu_users) cannot be used anywhere, as + * after the refcount goes to 0, the RCU callback being scheduled will + * cause the memory backing the refcount to again be nonzero due to the + * fields sharing a union. The other is that we can't rely on RCU to + * guarantee that a task is valid in a BPF program. This is because a + * task could have already transitioned to being in the TASK_DEAD + * state, had its rcu_users refcount go to 0, and its rcu callback + * invoked in which it drops its single p->usage reference. At this + * point the task will be freed as soon as the last p->usage reference + * goes to 0, without waiting for another RCU gp to elapse. The only + * way that a BPF program can guarantee that a task is valid is in this + * scenario is to hold a p->usage refcount itself. + * + * Until we're able to resolve this issue, either by pulling + * p->rcu_users and p->rcu out of the union, or by getting rid of + * p->usage and just using p->rcu_users for refcounting, we'll just + * return NULL here. + */ + return NULL; +} + +/** + * bpf_task_kptr_get - Acquire a reference on a struct task_struct kptr. A task + * kptr acquired by this kfunc which is not subsequently stored in a map, must + * be released by calling bpf_task_release(). + * @pp: A pointer to a task kptr on which a reference is being acquired. + */ +struct task_struct *bpf_task_kptr_get(struct task_struct **pp) +{ + /* We must return NULL here until we have clarity on how to properly + * leverage RCU for ensuring a task's lifetime. See the comment above + * in bpf_task_acquire_not_zero() for more details. + */ + return NULL; +} + +/** + * bpf_task_release - Release the reference acquired on a task. + * @p: The task on which a reference is being released. + */ +void bpf_task_release(struct task_struct *p) +{ + if (!p) + return; + + put_task_struct(p); +} + +#ifdef CONFIG_CGROUPS +/** + * bpf_cgroup_acquire - Acquire a reference to a cgroup. A cgroup acquired by + * this kfunc which is not stored in a map as a kptr, must be released by + * calling bpf_cgroup_release(). + * @cgrp: The cgroup on which a reference is being acquired. + */ +struct cgroup *bpf_cgroup_acquire(struct cgroup *cgrp) +{ + cgroup_get(cgrp); + return cgrp; +} + +/** + * bpf_cgroup_kptr_get - Acquire a reference on a struct cgroup kptr. A cgroup + * kptr acquired by this kfunc which is not subsequently stored in a map, must + * be released by calling bpf_cgroup_release(). + * @cgrpp: A pointer to a cgroup kptr on which a reference is being acquired. + */ +struct cgroup *bpf_cgroup_kptr_get(struct cgroup **cgrpp) +{ + struct cgroup *cgrp; + + rcu_read_lock(); + /* Another context could remove the cgroup from the map and release it + * at any time, including after we've done the lookup above. This is + * safe because we're in an RCU read region, so the cgroup is + * guaranteed to remain valid until at least the rcu_read_unlock() + * below. + */ + cgrp = READ_ONCE(*cgrpp); + + if (cgrp && !cgroup_tryget(cgrp)) + /* If the cgroup had been removed from the map and freed as + * described above, cgroup_tryget() will return false. The + * cgroup will be freed at some point after the current RCU gp + * has ended, so just return NULL to the user. + */ + cgrp = NULL; + rcu_read_unlock(); + + return cgrp; +} + +/** + * bpf_cgroup_release - Release the reference acquired on a cgroup. + * If this kfunc is invoked in an RCU read region, the cgroup is guaranteed to + * not be freed until the current grace period has ended, even if its refcount + * drops to 0. + * @cgrp: The cgroup on which a reference is being released. + */ +void bpf_cgroup_release(struct cgroup *cgrp) +{ + if (!cgrp) + return; + + cgroup_put(cgrp); +} + +/** + * bpf_cgroup_ancestor - Perform a lookup on an entry in a cgroup's ancestor + * array. A cgroup returned by this kfunc which is not subsequently stored in a + * map, must be released by calling bpf_cgroup_release(). + * @cgrp: The cgroup for which we're performing a lookup. + * @level: The level of ancestor to look up. + */ +struct cgroup *bpf_cgroup_ancestor(struct cgroup *cgrp, int level) +{ + struct cgroup *ancestor; + + if (level > cgrp->level || level < 0) + return NULL; + + ancestor = cgrp->ancestors[level]; + cgroup_get(ancestor); + return ancestor; +} +#endif /* CONFIG_CGROUPS */ + +/** + * bpf_task_from_pid - Find a struct task_struct from its pid by looking it up + * in the root pid namespace idr. If a task is returned, it must either be + * stored in a map, or released with bpf_task_release(). + * @pid: The pid of the task being looked up. + */ +struct task_struct *bpf_task_from_pid(s32 pid) +{ + struct task_struct *p; + + rcu_read_lock(); + p = find_task_by_pid_ns(pid, &init_pid_ns); + if (p) + bpf_task_acquire(p); + rcu_read_unlock(); + + return p; +} + +void *bpf_cast_to_kern_ctx(void *obj) +{ + return obj; +} + +void *bpf_rdonly_cast(void *obj__ign, u32 btf_id__k) +{ + return obj__ign; +} + +void bpf_rcu_read_lock(void) +{ + rcu_read_lock(); +} + +void bpf_rcu_read_unlock(void) +{ + rcu_read_unlock(); +} + +__diag_pop(); + +BTF_SET8_START(generic_btf_ids) #ifdef CONFIG_KEXEC_CORE BTF_ID_FLAGS(func, crash_kexec, KF_DESTRUCTIVE) #endif -BTF_SET8_END(tracing_btf_ids) +BTF_ID_FLAGS(func, bpf_obj_new_impl, KF_ACQUIRE | KF_RET_NULL) +BTF_ID_FLAGS(func, bpf_obj_drop_impl, KF_RELEASE) +BTF_ID_FLAGS(func, bpf_list_push_front) +BTF_ID_FLAGS(func, bpf_list_push_back) +BTF_ID_FLAGS(func, bpf_list_pop_front, KF_ACQUIRE | KF_RET_NULL) +BTF_ID_FLAGS(func, bpf_list_pop_back, KF_ACQUIRE | KF_RET_NULL) +BTF_ID_FLAGS(func, bpf_task_acquire, KF_ACQUIRE | KF_TRUSTED_ARGS) +BTF_ID_FLAGS(func, bpf_task_acquire_not_zero, KF_ACQUIRE | KF_RCU | KF_RET_NULL) +BTF_ID_FLAGS(func, bpf_task_kptr_get, KF_ACQUIRE | KF_KPTR_GET | KF_RET_NULL) +BTF_ID_FLAGS(func, bpf_task_release, KF_RELEASE) +#ifdef CONFIG_CGROUPS +BTF_ID_FLAGS(func, bpf_cgroup_acquire, KF_ACQUIRE | KF_TRUSTED_ARGS) +BTF_ID_FLAGS(func, bpf_cgroup_kptr_get, KF_ACQUIRE | KF_KPTR_GET | KF_RET_NULL) +BTF_ID_FLAGS(func, bpf_cgroup_release, KF_RELEASE) +BTF_ID_FLAGS(func, bpf_cgroup_ancestor, KF_ACQUIRE | KF_TRUSTED_ARGS | KF_RET_NULL) +#endif +BTF_ID_FLAGS(func, bpf_task_from_pid, KF_ACQUIRE | KF_RET_NULL) +BTF_SET8_END(generic_btf_ids) -static const struct btf_kfunc_id_set tracing_kfunc_set = { +static const struct btf_kfunc_id_set generic_kfunc_set = { .owner = THIS_MODULE, - .set = &tracing_btf_ids, + .set = &generic_btf_ids, +}; + + +BTF_ID_LIST(generic_dtor_ids) +BTF_ID(struct, task_struct) +BTF_ID(func, bpf_task_release) +#ifdef CONFIG_CGROUPS +BTF_ID(struct, cgroup) +BTF_ID(func, bpf_cgroup_release) +#endif + +BTF_SET8_START(common_btf_ids) +BTF_ID_FLAGS(func, bpf_cast_to_kern_ctx) +BTF_ID_FLAGS(func, bpf_rdonly_cast) +BTF_ID_FLAGS(func, bpf_rcu_read_lock) +BTF_ID_FLAGS(func, bpf_rcu_read_unlock) +BTF_SET8_END(common_btf_ids) + +static const struct btf_kfunc_id_set common_kfunc_set = { + .owner = THIS_MODULE, + .set = &common_btf_ids, }; static int __init kfunc_init(void) { - return register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &tracing_kfunc_set); + int ret; + const struct btf_id_dtor_kfunc generic_dtors[] = { + { + .btf_id = generic_dtor_ids[0], + .kfunc_btf_id = generic_dtor_ids[1] + }, +#ifdef CONFIG_CGROUPS + { + .btf_id = generic_dtor_ids[2], + .kfunc_btf_id = generic_dtor_ids[3] + }, +#endif + }; + + ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &generic_kfunc_set); + ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &generic_kfunc_set); + ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_STRUCT_OPS, &generic_kfunc_set); + ret = ret ?: register_btf_id_dtor_kfuncs(generic_dtors, + ARRAY_SIZE(generic_dtors), + THIS_MODULE); + return ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_UNSPEC, &common_kfunc_set); } late_initcall(kfunc_init); diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c index 098cf336fae6..e90d9f63edc5 100644 --- a/kernel/bpf/local_storage.c +++ b/kernel/bpf/local_storage.c @@ -151,7 +151,7 @@ static int cgroup_storage_update_elem(struct bpf_map *map, void *key, return -EINVAL; if (unlikely((flags & BPF_F_LOCK) && - !map_value_has_spin_lock(map))) + !btf_record_has_field(map->record, BPF_SPIN_LOCK))) return -EINVAL; storage = cgroup_storage_lookup((struct bpf_cgroup_storage_map *)map, diff --git a/kernel/bpf/map_in_map.c b/kernel/bpf/map_in_map.c index 135205d0d560..38136ec4e095 100644 --- a/kernel/bpf/map_in_map.c +++ b/kernel/bpf/map_in_map.c @@ -12,6 +12,7 @@ struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd) struct bpf_map *inner_map, *inner_map_meta; u32 inner_map_meta_size; struct fd f; + int ret; f = fdget(inner_map_ufd); inner_map = __bpf_map_get(f); @@ -20,18 +21,13 @@ struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd) /* Does not support >1 level map-in-map */ if (inner_map->inner_map_meta) { - fdput(f); - return ERR_PTR(-EINVAL); + ret = -EINVAL; + goto put; } if (!inner_map->ops->map_meta_equal) { - fdput(f); - return ERR_PTR(-ENOTSUPP); - } - - if (map_value_has_spin_lock(inner_map)) { - fdput(f); - return ERR_PTR(-ENOTSUPP); + ret = -ENOTSUPP; + goto put; } inner_map_meta_size = sizeof(*inner_map_meta); @@ -41,8 +37,8 @@ struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd) inner_map_meta = kzalloc(inner_map_meta_size, GFP_USER); if (!inner_map_meta) { - fdput(f); - return ERR_PTR(-ENOMEM); + ret = -ENOMEM; + goto put; } inner_map_meta->map_type = inner_map->map_type; @@ -50,9 +46,33 @@ struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd) inner_map_meta->value_size = inner_map->value_size; inner_map_meta->map_flags = inner_map->map_flags; inner_map_meta->max_entries = inner_map->max_entries; - inner_map_meta->spin_lock_off = inner_map->spin_lock_off; - inner_map_meta->timer_off = inner_map->timer_off; - inner_map_meta->kptr_off_tab = bpf_map_copy_kptr_off_tab(inner_map); + + inner_map_meta->record = btf_record_dup(inner_map->record); + if (IS_ERR(inner_map_meta->record)) { + /* btf_record_dup returns NULL or valid pointer in case of + * invalid/empty/valid, but ERR_PTR in case of errors. During + * equality NULL or IS_ERR is equivalent. + */ + ret = PTR_ERR(inner_map_meta->record); + goto free; + } + if (inner_map_meta->record) { + struct btf_field_offs *field_offs; + /* If btf_record is !IS_ERR_OR_NULL, then field_offs is always + * valid. + */ + field_offs = kmemdup(inner_map->field_offs, sizeof(*inner_map->field_offs), GFP_KERNEL | __GFP_NOWARN); + if (!field_offs) { + ret = -ENOMEM; + goto free_rec; + } + inner_map_meta->field_offs = field_offs; + } + /* Note: We must use the same BTF, as we also used btf_record_dup above + * which relies on BTF being same for both maps, as some members like + * record->fields.list_head have pointers like value_rec pointing into + * inner_map->btf. + */ if (inner_map->btf) { btf_get(inner_map->btf); inner_map_meta->btf = inner_map->btf; @@ -68,11 +88,19 @@ struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd) fdput(f); return inner_map_meta; +free_rec: + btf_record_free(inner_map_meta->record); +free: + kfree(inner_map_meta); +put: + fdput(f); + return ERR_PTR(ret); } void bpf_map_meta_free(struct bpf_map *map_meta) { - bpf_map_free_kptr_off_tab(map_meta); + kfree(map_meta->field_offs); + bpf_map_free_record(map_meta); btf_put(map_meta->btf); kfree(map_meta); } @@ -84,9 +112,8 @@ bool bpf_map_meta_equal(const struct bpf_map *meta0, return meta0->map_type == meta1->map_type && meta0->key_size == meta1->key_size && meta0->value_size == meta1->value_size && - meta0->timer_off == meta1->timer_off && meta0->map_flags == meta1->map_flags && - bpf_map_equal_kptr_off_tab(meta0, meta1); + btf_record_equal(meta0->record, meta1->record); } void *bpf_map_fd_get_ptr(struct bpf_map *map, diff --git a/kernel/bpf/memalloc.c b/kernel/bpf/memalloc.c index 4901fa1048cd..1db156405b68 100644 --- a/kernel/bpf/memalloc.c +++ b/kernel/bpf/memalloc.c @@ -71,7 +71,7 @@ static int bpf_mem_cache_idx(size_t size) if (size <= 192) return size_index[(size - 1) / 8] - 1; - return fls(size - 1) - 1; + return fls(size - 1) - 2; } #define NUM_CACHES 11 @@ -171,9 +171,24 @@ static void alloc_bulk(struct bpf_mem_cache *c, int cnt, int node) memcg = get_memcg(c); old_memcg = set_active_memcg(memcg); for (i = 0; i < cnt; i++) { - obj = __alloc(c, node); - if (!obj) - break; + /* + * free_by_rcu is only manipulated by irq work refill_work(). + * IRQ works on the same CPU are called sequentially, so it is + * safe to use __llist_del_first() here. If alloc_bulk() is + * invoked by the initial prefill, there will be no running + * refill_work(), so __llist_del_first() is fine as well. + * + * In most cases, objects on free_by_rcu are from the same CPU. + * If some objects come from other CPUs, it doesn't incur any + * harm because NUMA_NO_NODE means the preference for current + * numa node and it is not a guarantee. + */ + obj = __llist_del_first(&c->free_by_rcu); + if (!obj) { + obj = __alloc(c, node); + if (!obj) + break; + } if (IS_ENABLED(CONFIG_PREEMPT_RT)) /* In RT irq_work runs in per-cpu kthread, so disable * interrupts to avoid preemption and interrupts and @@ -222,9 +237,13 @@ static void __free_rcu(struct rcu_head *head) static void __free_rcu_tasks_trace(struct rcu_head *head) { - struct bpf_mem_cache *c = container_of(head, struct bpf_mem_cache, rcu); - - call_rcu(&c->rcu, __free_rcu); + /* If RCU Tasks Trace grace period implies RCU grace period, + * there is no need to invoke call_rcu(). + */ + if (rcu_trace_implies_rcu_gp()) + __free_rcu(head); + else + call_rcu(head, __free_rcu); } static void enque_to_free(struct bpf_mem_cache *c, void *obj) @@ -253,8 +272,9 @@ static void do_call_rcu(struct bpf_mem_cache *c) */ __llist_add(llnode, &c->waiting_for_gp); /* Use call_rcu_tasks_trace() to wait for sleepable progs to finish. - * Then use call_rcu() to wait for normal progs to finish - * and finally do free_one() on each element. + * If RCU Tasks Trace grace period implies RCU grace period, free + * these elements directly, else use call_rcu() to wait for normal + * progs to finish and finally do free_one() on each element. */ call_rcu_tasks_trace(&c->rcu, __free_rcu_tasks_trace); } @@ -444,9 +464,17 @@ static void free_mem_alloc(struct bpf_mem_alloc *ma) { /* waiting_for_gp lists was drained, but __free_rcu might * still execute. Wait for it now before we freeing percpu caches. + * + * rcu_barrier_tasks_trace() doesn't imply synchronize_rcu_tasks_trace(), + * but rcu_barrier_tasks_trace() and rcu_barrier() below are only used + * to wait for the pending __free_rcu_tasks_trace() and __free_rcu(), + * so if call_rcu(head, __free_rcu) is skipped due to + * rcu_trace_implies_rcu_gp(), it will be OK to skip rcu_barrier() by + * using rcu_trace_implies_rcu_gp() as well. */ rcu_barrier_tasks_trace(); - rcu_barrier(); + if (!rcu_trace_implies_rcu_gp()) + rcu_barrier(); free_mem_alloc_no_barrier(ma); } diff --git a/kernel/bpf/offload.c b/kernel/bpf/offload.c index 13e4efc971e6..190d9f9dc987 100644 --- a/kernel/bpf/offload.c +++ b/kernel/bpf/offload.c @@ -216,9 +216,6 @@ static void __bpf_prog_offload_destroy(struct bpf_prog *prog) if (offload->dev_state) offload->offdev->ops->destroy(prog); - /* Make sure BPF_PROG_GET_NEXT_ID can't find this dead program */ - bpf_prog_free_id(prog, true); - list_del_init(&offload->offloads); kfree(offload); prog->aux->offload = NULL; diff --git a/kernel/bpf/ringbuf.c b/kernel/bpf/ringbuf.c index 9e832acf4692..80f4b4d88aaf 100644 --- a/kernel/bpf/ringbuf.c +++ b/kernel/bpf/ringbuf.c @@ -447,7 +447,7 @@ BPF_CALL_3(bpf_ringbuf_reserve, struct bpf_map *, map, u64, size, u64, flags) const struct bpf_func_proto bpf_ringbuf_reserve_proto = { .func = bpf_ringbuf_reserve, - .ret_type = RET_PTR_TO_ALLOC_MEM_OR_NULL, + .ret_type = RET_PTR_TO_RINGBUF_MEM_OR_NULL, .arg1_type = ARG_CONST_MAP_PTR, .arg2_type = ARG_CONST_ALLOC_SIZE_OR_ZERO, .arg3_type = ARG_ANYTHING, @@ -490,7 +490,7 @@ BPF_CALL_2(bpf_ringbuf_submit, void *, sample, u64, flags) const struct bpf_func_proto bpf_ringbuf_submit_proto = { .func = bpf_ringbuf_submit, .ret_type = RET_VOID, - .arg1_type = ARG_PTR_TO_ALLOC_MEM | OBJ_RELEASE, + .arg1_type = ARG_PTR_TO_RINGBUF_MEM | OBJ_RELEASE, .arg2_type = ARG_ANYTHING, }; @@ -503,7 +503,7 @@ BPF_CALL_2(bpf_ringbuf_discard, void *, sample, u64, flags) const struct bpf_func_proto bpf_ringbuf_discard_proto = { .func = bpf_ringbuf_discard, .ret_type = RET_VOID, - .arg1_type = ARG_PTR_TO_ALLOC_MEM | OBJ_RELEASE, + .arg1_type = ARG_PTR_TO_RINGBUF_MEM | OBJ_RELEASE, .arg2_type = ARG_ANYTHING, }; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 7b373a5e861f..ecca9366c7a6 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -175,8 +175,8 @@ static void maybe_wait_bpf_programs(struct bpf_map *map) synchronize_rcu(); } -static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key, - void *value, __u64 flags) +static int bpf_map_update_value(struct bpf_map *map, struct file *map_file, + void *key, void *value, __u64 flags) { int err; @@ -190,7 +190,7 @@ static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key, map->map_type == BPF_MAP_TYPE_SOCKMAP) { return sock_map_update_elem_sys(map, key, value, flags); } else if (IS_FD_PROG_ARRAY(map)) { - return bpf_fd_array_map_update_elem(map, f.file, key, value, + return bpf_fd_array_map_update_elem(map, map_file, key, value, flags); } @@ -205,12 +205,12 @@ static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key, flags); } else if (IS_FD_ARRAY(map)) { rcu_read_lock(); - err = bpf_fd_array_map_update_elem(map, f.file, key, value, + err = bpf_fd_array_map_update_elem(map, map_file, key, value, flags); rcu_read_unlock(); } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { rcu_read_lock(); - err = bpf_fd_htab_map_update_elem(map, f.file, key, value, + err = bpf_fd_htab_map_update_elem(map, map_file, key, value, flags); rcu_read_unlock(); } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { @@ -495,114 +495,181 @@ static void bpf_map_release_memcg(struct bpf_map *map) } #endif -static int bpf_map_kptr_off_cmp(const void *a, const void *b) +static int btf_field_cmp(const void *a, const void *b) { - const struct bpf_map_value_off_desc *off_desc1 = a, *off_desc2 = b; + const struct btf_field *f1 = a, *f2 = b; - if (off_desc1->offset < off_desc2->offset) + if (f1->offset < f2->offset) return -1; - else if (off_desc1->offset > off_desc2->offset) + else if (f1->offset > f2->offset) return 1; return 0; } -struct bpf_map_value_off_desc *bpf_map_kptr_off_contains(struct bpf_map *map, u32 offset) +struct btf_field *btf_record_find(const struct btf_record *rec, u32 offset, + enum btf_field_type type) { - /* Since members are iterated in btf_find_field in increasing order, - * offsets appended to kptr_off_tab are in increasing order, so we can - * do bsearch to find exact match. - */ - struct bpf_map_value_off *tab; + struct btf_field *field; - if (!map_value_has_kptrs(map)) + if (IS_ERR_OR_NULL(rec) || !(rec->field_mask & type)) + return NULL; + field = bsearch(&offset, rec->fields, rec->cnt, sizeof(rec->fields[0]), btf_field_cmp); + if (!field || !(field->type & type)) return NULL; - tab = map->kptr_off_tab; - return bsearch(&offset, tab->off, tab->nr_off, sizeof(tab->off[0]), bpf_map_kptr_off_cmp); + return field; } -void bpf_map_free_kptr_off_tab(struct bpf_map *map) +void btf_record_free(struct btf_record *rec) { - struct bpf_map_value_off *tab = map->kptr_off_tab; int i; - if (!map_value_has_kptrs(map)) + if (IS_ERR_OR_NULL(rec)) return; - for (i = 0; i < tab->nr_off; i++) { - if (tab->off[i].kptr.module) - module_put(tab->off[i].kptr.module); - btf_put(tab->off[i].kptr.btf); + for (i = 0; i < rec->cnt; i++) { + switch (rec->fields[i].type) { + case BPF_SPIN_LOCK: + case BPF_TIMER: + break; + case BPF_KPTR_UNREF: + case BPF_KPTR_REF: + if (rec->fields[i].kptr.module) + module_put(rec->fields[i].kptr.module); + btf_put(rec->fields[i].kptr.btf); + break; + case BPF_LIST_HEAD: + case BPF_LIST_NODE: + /* Nothing to release for bpf_list_head */ + break; + default: + WARN_ON_ONCE(1); + continue; + } } - kfree(tab); - map->kptr_off_tab = NULL; + kfree(rec); } -struct bpf_map_value_off *bpf_map_copy_kptr_off_tab(const struct bpf_map *map) +void bpf_map_free_record(struct bpf_map *map) { - struct bpf_map_value_off *tab = map->kptr_off_tab, *new_tab; - int size, i; + btf_record_free(map->record); + map->record = NULL; +} - if (!map_value_has_kptrs(map)) - return ERR_PTR(-ENOENT); - size = offsetof(struct bpf_map_value_off, off[tab->nr_off]); - new_tab = kmemdup(tab, size, GFP_KERNEL | __GFP_NOWARN); - if (!new_tab) +struct btf_record *btf_record_dup(const struct btf_record *rec) +{ + const struct btf_field *fields; + struct btf_record *new_rec; + int ret, size, i; + + if (IS_ERR_OR_NULL(rec)) + return NULL; + size = offsetof(struct btf_record, fields[rec->cnt]); + new_rec = kmemdup(rec, size, GFP_KERNEL | __GFP_NOWARN); + if (!new_rec) return ERR_PTR(-ENOMEM); - /* Do a deep copy of the kptr_off_tab */ - for (i = 0; i < tab->nr_off; i++) { - btf_get(tab->off[i].kptr.btf); - if (tab->off[i].kptr.module && !try_module_get(tab->off[i].kptr.module)) { - while (i--) { - if (tab->off[i].kptr.module) - module_put(tab->off[i].kptr.module); - btf_put(tab->off[i].kptr.btf); + /* Do a deep copy of the btf_record */ + fields = rec->fields; + new_rec->cnt = 0; + for (i = 0; i < rec->cnt; i++) { + switch (fields[i].type) { + case BPF_SPIN_LOCK: + case BPF_TIMER: + break; + case BPF_KPTR_UNREF: + case BPF_KPTR_REF: + btf_get(fields[i].kptr.btf); + if (fields[i].kptr.module && !try_module_get(fields[i].kptr.module)) { + ret = -ENXIO; + goto free; } - kfree(new_tab); - return ERR_PTR(-ENXIO); + break; + case BPF_LIST_HEAD: + case BPF_LIST_NODE: + /* Nothing to acquire for bpf_list_head */ + break; + default: + ret = -EFAULT; + WARN_ON_ONCE(1); + goto free; } + new_rec->cnt++; } - return new_tab; + return new_rec; +free: + btf_record_free(new_rec); + return ERR_PTR(ret); } -bool bpf_map_equal_kptr_off_tab(const struct bpf_map *map_a, const struct bpf_map *map_b) +bool btf_record_equal(const struct btf_record *rec_a, const struct btf_record *rec_b) { - struct bpf_map_value_off *tab_a = map_a->kptr_off_tab, *tab_b = map_b->kptr_off_tab; - bool a_has_kptr = map_value_has_kptrs(map_a), b_has_kptr = map_value_has_kptrs(map_b); + bool a_has_fields = !IS_ERR_OR_NULL(rec_a), b_has_fields = !IS_ERR_OR_NULL(rec_b); int size; - if (!a_has_kptr && !b_has_kptr) + if (!a_has_fields && !b_has_fields) return true; - if (a_has_kptr != b_has_kptr) + if (a_has_fields != b_has_fields) return false; - if (tab_a->nr_off != tab_b->nr_off) + if (rec_a->cnt != rec_b->cnt) return false; - size = offsetof(struct bpf_map_value_off, off[tab_a->nr_off]); - return !memcmp(tab_a, tab_b, size); + size = offsetof(struct btf_record, fields[rec_a->cnt]); + /* btf_parse_fields uses kzalloc to allocate a btf_record, so unused + * members are zeroed out. So memcmp is safe to do without worrying + * about padding/unused fields. + * + * While spin_lock, timer, and kptr have no relation to map BTF, + * list_head metadata is specific to map BTF, the btf and value_rec + * members in particular. btf is the map BTF, while value_rec points to + * btf_record in that map BTF. + * + * So while by default, we don't rely on the map BTF (which the records + * were parsed from) matching for both records, which is not backwards + * compatible, in case list_head is part of it, we implicitly rely on + * that by way of depending on memcmp succeeding for it. + */ + return !memcmp(rec_a, rec_b, size); } -/* Caller must ensure map_value_has_kptrs is true. Note that this function can - * be called on a map value while the map_value is visible to BPF programs, as - * it ensures the correct synchronization, and we already enforce the same using - * the bpf_kptr_xchg helper on the BPF program side for referenced kptrs. - */ -void bpf_map_free_kptrs(struct bpf_map *map, void *map_value) +void bpf_obj_free_timer(const struct btf_record *rec, void *obj) { - struct bpf_map_value_off *tab = map->kptr_off_tab; - unsigned long *btf_id_ptr; - int i; + if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_TIMER))) + return; + bpf_timer_cancel_and_free(obj + rec->timer_off); +} - for (i = 0; i < tab->nr_off; i++) { - struct bpf_map_value_off_desc *off_desc = &tab->off[i]; - unsigned long old_ptr; +void bpf_obj_free_fields(const struct btf_record *rec, void *obj) +{ + const struct btf_field *fields; + int i; - btf_id_ptr = map_value + off_desc->offset; - if (off_desc->type == BPF_KPTR_UNREF) { - u64 *p = (u64 *)btf_id_ptr; + if (IS_ERR_OR_NULL(rec)) + return; + fields = rec->fields; + for (i = 0; i < rec->cnt; i++) { + const struct btf_field *field = &fields[i]; + void *field_ptr = obj + field->offset; - WRITE_ONCE(*p, 0); + switch (fields[i].type) { + case BPF_SPIN_LOCK: + break; + case BPF_TIMER: + bpf_timer_cancel_and_free(field_ptr); + break; + case BPF_KPTR_UNREF: + WRITE_ONCE(*(u64 *)field_ptr, 0); + break; + case BPF_KPTR_REF: + field->kptr.dtor((void *)xchg((unsigned long *)field_ptr, 0)); + break; + case BPF_LIST_HEAD: + if (WARN_ON_ONCE(rec->spin_lock_off < 0)) + continue; + bpf_list_head_free(field, field_ptr, obj + rec->spin_lock_off); + break; + case BPF_LIST_NODE: + break; + default: + WARN_ON_ONCE(1); continue; } - old_ptr = xchg(btf_id_ptr, 0); - off_desc->kptr.dtor((void *)old_ptr); } } @@ -610,14 +677,24 @@ void bpf_map_free_kptrs(struct bpf_map *map, void *map_value) static void bpf_map_free_deferred(struct work_struct *work) { struct bpf_map *map = container_of(work, struct bpf_map, work); + struct btf_field_offs *foffs = map->field_offs; + struct btf_record *rec = map->record; security_bpf_map_free(map); - kfree(map->off_arr); bpf_map_release_memcg(map); - /* implementation dependent freeing, map_free callback also does - * bpf_map_free_kptr_off_tab, if needed. - */ + /* implementation dependent freeing */ map->ops->map_free(map); + /* Delay freeing of field_offs and btf_record for maps, as map_free + * callback usually needs access to them. It is better to do it here + * than require each callback to do the free itself manually. + * + * Note that the btf_record stashed in map->inner_map_meta->record was + * already freed using the map_free callback for map in map case which + * eventually calls bpf_map_free_meta, since inner_map_meta is only a + * template bpf_map struct used during verification. + */ + kfree(foffs); + btf_record_free(rec); } static void bpf_map_put_uref(struct bpf_map *map) @@ -778,8 +855,7 @@ static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma) struct bpf_map *map = filp->private_data; int err; - if (!map->ops->map_mmap || map_value_has_spin_lock(map) || - map_value_has_timer(map) || map_value_has_kptrs(map)) + if (!map->ops->map_mmap || !IS_ERR_OR_NULL(map->record)) return -ENOTSUPP; if (!(vma->vm_flags & VM_SHARED)) @@ -906,84 +982,6 @@ int map_check_no_btf(const struct bpf_map *map, return -ENOTSUPP; } -static int map_off_arr_cmp(const void *_a, const void *_b, const void *priv) -{ - const u32 a = *(const u32 *)_a; - const u32 b = *(const u32 *)_b; - - if (a < b) - return -1; - else if (a > b) - return 1; - return 0; -} - -static void map_off_arr_swap(void *_a, void *_b, int size, const void *priv) -{ - struct bpf_map *map = (struct bpf_map *)priv; - u32 *off_base = map->off_arr->field_off; - u32 *a = _a, *b = _b; - u8 *sz_a, *sz_b; - - sz_a = map->off_arr->field_sz + (a - off_base); - sz_b = map->off_arr->field_sz + (b - off_base); - - swap(*a, *b); - swap(*sz_a, *sz_b); -} - -static int bpf_map_alloc_off_arr(struct bpf_map *map) -{ - bool has_spin_lock = map_value_has_spin_lock(map); - bool has_timer = map_value_has_timer(map); - bool has_kptrs = map_value_has_kptrs(map); - struct bpf_map_off_arr *off_arr; - u32 i; - - if (!has_spin_lock && !has_timer && !has_kptrs) { - map->off_arr = NULL; - return 0; - } - - off_arr = kmalloc(sizeof(*map->off_arr), GFP_KERNEL | __GFP_NOWARN); - if (!off_arr) - return -ENOMEM; - map->off_arr = off_arr; - - off_arr->cnt = 0; - if (has_spin_lock) { - i = off_arr->cnt; - - off_arr->field_off[i] = map->spin_lock_off; - off_arr->field_sz[i] = sizeof(struct bpf_spin_lock); - off_arr->cnt++; - } - if (has_timer) { - i = off_arr->cnt; - - off_arr->field_off[i] = map->timer_off; - off_arr->field_sz[i] = sizeof(struct bpf_timer); - off_arr->cnt++; - } - if (has_kptrs) { - struct bpf_map_value_off *tab = map->kptr_off_tab; - u32 *off = &off_arr->field_off[off_arr->cnt]; - u8 *sz = &off_arr->field_sz[off_arr->cnt]; - - for (i = 0; i < tab->nr_off; i++) { - *off++ = tab->off[i].offset; - *sz++ = sizeof(u64); - } - off_arr->cnt += tab->nr_off; - } - - if (off_arr->cnt == 1) - return 0; - sort_r(off_arr->field_off, off_arr->cnt, sizeof(off_arr->field_off[0]), - map_off_arr_cmp, map_off_arr_swap, map); - return 0; -} - static int map_check_btf(struct bpf_map *map, const struct btf *btf, u32 btf_key_id, u32 btf_value_id) { @@ -1006,39 +1004,12 @@ static int map_check_btf(struct bpf_map *map, const struct btf *btf, if (!value_type || value_size != map->value_size) return -EINVAL; - map->spin_lock_off = btf_find_spin_lock(btf, value_type); - - if (map_value_has_spin_lock(map)) { - if (map->map_flags & BPF_F_RDONLY_PROG) - return -EACCES; - if (map->map_type != BPF_MAP_TYPE_HASH && - map->map_type != BPF_MAP_TYPE_ARRAY && - map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && - map->map_type != BPF_MAP_TYPE_SK_STORAGE && - map->map_type != BPF_MAP_TYPE_INODE_STORAGE && - map->map_type != BPF_MAP_TYPE_TASK_STORAGE) - return -ENOTSUPP; - if (map->spin_lock_off + sizeof(struct bpf_spin_lock) > - map->value_size) { - WARN_ONCE(1, - "verifier bug spin_lock_off %d value_size %d\n", - map->spin_lock_off, map->value_size); - return -EFAULT; - } - } + map->record = btf_parse_fields(btf, value_type, + BPF_SPIN_LOCK | BPF_TIMER | BPF_KPTR | BPF_LIST_HEAD, + map->value_size); + if (!IS_ERR_OR_NULL(map->record)) { + int i; - map->timer_off = btf_find_timer(btf, value_type); - if (map_value_has_timer(map)) { - if (map->map_flags & BPF_F_RDONLY_PROG) - return -EACCES; - if (map->map_type != BPF_MAP_TYPE_HASH && - map->map_type != BPF_MAP_TYPE_LRU_HASH && - map->map_type != BPF_MAP_TYPE_ARRAY) - return -EOPNOTSUPP; - } - - map->kptr_off_tab = btf_parse_kptrs(btf, value_type); - if (map_value_has_kptrs(map)) { if (!bpf_capable()) { ret = -EPERM; goto free_map_tab; @@ -1047,15 +1018,60 @@ static int map_check_btf(struct bpf_map *map, const struct btf *btf, ret = -EACCES; goto free_map_tab; } - if (map->map_type != BPF_MAP_TYPE_HASH && - map->map_type != BPF_MAP_TYPE_LRU_HASH && - map->map_type != BPF_MAP_TYPE_ARRAY && - map->map_type != BPF_MAP_TYPE_PERCPU_ARRAY) { - ret = -EOPNOTSUPP; - goto free_map_tab; + for (i = 0; i < sizeof(map->record->field_mask) * 8; i++) { + switch (map->record->field_mask & (1 << i)) { + case 0: + continue; + case BPF_SPIN_LOCK: + if (map->map_type != BPF_MAP_TYPE_HASH && + map->map_type != BPF_MAP_TYPE_ARRAY && + map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && + map->map_type != BPF_MAP_TYPE_SK_STORAGE && + map->map_type != BPF_MAP_TYPE_INODE_STORAGE && + map->map_type != BPF_MAP_TYPE_TASK_STORAGE && + map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) { + ret = -EOPNOTSUPP; + goto free_map_tab; + } + break; + case BPF_TIMER: + if (map->map_type != BPF_MAP_TYPE_HASH && + map->map_type != BPF_MAP_TYPE_LRU_HASH && + map->map_type != BPF_MAP_TYPE_ARRAY) { + ret = -EOPNOTSUPP; + goto free_map_tab; + } + break; + case BPF_KPTR_UNREF: + case BPF_KPTR_REF: + if (map->map_type != BPF_MAP_TYPE_HASH && + map->map_type != BPF_MAP_TYPE_LRU_HASH && + map->map_type != BPF_MAP_TYPE_ARRAY && + map->map_type != BPF_MAP_TYPE_PERCPU_ARRAY) { + ret = -EOPNOTSUPP; + goto free_map_tab; + } + break; + case BPF_LIST_HEAD: + if (map->map_type != BPF_MAP_TYPE_HASH && + map->map_type != BPF_MAP_TYPE_LRU_HASH && + map->map_type != BPF_MAP_TYPE_ARRAY) { + ret = -EOPNOTSUPP; + goto free_map_tab; + } + break; + default: + /* Fail if map_type checks are missing for a field type */ + ret = -EOPNOTSUPP; + goto free_map_tab; + } } } + ret = btf_check_and_fixup_fields(btf, map->record); + if (ret < 0) + goto free_map_tab; + if (map->ops->map_check_btf) { ret = map->ops->map_check_btf(map, btf, key_type, value_type); if (ret < 0) @@ -1064,7 +1080,7 @@ static int map_check_btf(struct bpf_map *map, const struct btf *btf, return ret; free_map_tab: - bpf_map_free_kptr_off_tab(map); + bpf_map_free_record(map); return ret; } @@ -1073,6 +1089,7 @@ free_map_tab: static int map_create(union bpf_attr *attr) { int numa_node = bpf_map_attr_numa_node(attr); + struct btf_field_offs *foffs; struct bpf_map *map; int f_flags; int err; @@ -1117,8 +1134,6 @@ static int map_create(union bpf_attr *attr) mutex_init(&map->freeze_mutex); spin_lock_init(&map->owner.lock); - map->spin_lock_off = -EINVAL; - map->timer_off = -EINVAL; if (attr->btf_key_type_id || attr->btf_value_type_id || /* Even the map's value is a kernel's struct, * the bpf_prog.o must have BTF to begin with @@ -1154,13 +1169,17 @@ static int map_create(union bpf_attr *attr) attr->btf_vmlinux_value_type_id; } - err = bpf_map_alloc_off_arr(map); - if (err) + + foffs = btf_parse_field_offs(map->record); + if (IS_ERR(foffs)) { + err = PTR_ERR(foffs); goto free_map; + } + map->field_offs = foffs; err = security_bpf_map_alloc(map); if (err) - goto free_map_off_arr; + goto free_map_field_offs; err = bpf_map_alloc_id(map); if (err) @@ -1184,8 +1203,8 @@ static int map_create(union bpf_attr *attr) free_map_sec: security_bpf_map_free(map); -free_map_off_arr: - kfree(map->off_arr); +free_map_field_offs: + kfree(map->field_offs); free_map: btf_put(map->btf); map->ops->map_free(map); @@ -1332,7 +1351,7 @@ static int map_lookup_elem(union bpf_attr *attr) } if ((attr->flags & BPF_F_LOCK) && - !map_value_has_spin_lock(map)) { + !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { err = -EINVAL; goto err_put; } @@ -1405,7 +1424,7 @@ static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr) } if ((attr->flags & BPF_F_LOCK) && - !map_value_has_spin_lock(map)) { + !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { err = -EINVAL; goto err_put; } @@ -1423,7 +1442,7 @@ static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr) goto free_key; } - err = bpf_map_update_value(map, f, key, value, attr->flags); + err = bpf_map_update_value(map, f.file, key, value, attr->flags); kvfree(value); free_key: @@ -1568,7 +1587,7 @@ int generic_map_delete_batch(struct bpf_map *map, return -EINVAL; if ((attr->batch.elem_flags & BPF_F_LOCK) && - !map_value_has_spin_lock(map)) { + !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { return -EINVAL; } @@ -1609,23 +1628,21 @@ int generic_map_delete_batch(struct bpf_map *map, return err; } -int generic_map_update_batch(struct bpf_map *map, +int generic_map_update_batch(struct bpf_map *map, struct file *map_file, const union bpf_attr *attr, union bpf_attr __user *uattr) { void __user *values = u64_to_user_ptr(attr->batch.values); void __user *keys = u64_to_user_ptr(attr->batch.keys); u32 value_size, cp, max_count; - int ufd = attr->batch.map_fd; void *key, *value; - struct fd f; int err = 0; if (attr->batch.elem_flags & ~BPF_F_LOCK) return -EINVAL; if ((attr->batch.elem_flags & BPF_F_LOCK) && - !map_value_has_spin_lock(map)) { + !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { return -EINVAL; } @@ -1645,7 +1662,6 @@ int generic_map_update_batch(struct bpf_map *map, return -ENOMEM; } - f = fdget(ufd); /* bpf_map_do_batch() guarantees ufd is valid */ for (cp = 0; cp < max_count; cp++) { err = -EFAULT; if (copy_from_user(key, keys + cp * map->key_size, @@ -1653,7 +1669,7 @@ int generic_map_update_batch(struct bpf_map *map, copy_from_user(value, values + cp * value_size, value_size)) break; - err = bpf_map_update_value(map, f, key, value, + err = bpf_map_update_value(map, map_file, key, value, attr->batch.elem_flags); if (err) @@ -1666,7 +1682,6 @@ int generic_map_update_batch(struct bpf_map *map, kvfree(value); kvfree(key); - fdput(f); return err; } @@ -1688,7 +1703,7 @@ int generic_map_lookup_batch(struct bpf_map *map, return -EINVAL; if ((attr->batch.elem_flags & BPF_F_LOCK) && - !map_value_has_spin_lock(map)) + !btf_record_has_field(map->record, BPF_SPIN_LOCK)) return -EINVAL; value_size = bpf_map_value_size(map); @@ -1810,7 +1825,7 @@ static int map_lookup_and_delete_elem(union bpf_attr *attr) } if ((attr->flags & BPF_F_LOCK) && - !map_value_has_spin_lock(map)) { + !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { err = -EINVAL; goto err_put; } @@ -1881,8 +1896,7 @@ static int map_freeze(const union bpf_attr *attr) if (IS_ERR(map)) return PTR_ERR(map); - if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS || - map_value_has_timer(map) || map_value_has_kptrs(map)) { + if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS || !IS_ERR_OR_NULL(map->record)) { fdput(f); return -ENOTSUPP; } @@ -1958,7 +1972,7 @@ static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op) return; if (audit_enabled == AUDIT_OFF) return; - if (op == BPF_AUDIT_LOAD) + if (!in_irq() && !irqs_disabled()) ctx = audit_context(); ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF); if (unlikely(!ab)) @@ -1987,7 +2001,7 @@ static int bpf_prog_alloc_id(struct bpf_prog *prog) return id > 0 ? 0 : id; } -void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock) +void bpf_prog_free_id(struct bpf_prog *prog) { unsigned long flags; @@ -1999,18 +2013,10 @@ void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock) if (!prog->aux->id) return; - if (do_idr_lock) - spin_lock_irqsave(&prog_idr_lock, flags); - else - __acquire(&prog_idr_lock); - + spin_lock_irqsave(&prog_idr_lock, flags); idr_remove(&prog_idr, prog->aux->id); prog->aux->id = 0; - - if (do_idr_lock) - spin_unlock_irqrestore(&prog_idr_lock, flags); - else - __release(&prog_idr_lock); + spin_unlock_irqrestore(&prog_idr_lock, flags); } static void __bpf_prog_put_rcu(struct rcu_head *rcu) @@ -2053,17 +2059,15 @@ static void bpf_prog_put_deferred(struct work_struct *work) prog = aux->prog; perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); bpf_audit_prog(prog, BPF_AUDIT_UNLOAD); + bpf_prog_free_id(prog); __bpf_prog_put_noref(prog, true); } -static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) +static void __bpf_prog_put(struct bpf_prog *prog) { struct bpf_prog_aux *aux = prog->aux; if (atomic64_dec_and_test(&aux->refcnt)) { - /* bpf_prog_free_id() must be called first */ - bpf_prog_free_id(prog, do_idr_lock); - if (in_irq() || irqs_disabled()) { INIT_WORK(&aux->work, bpf_prog_put_deferred); schedule_work(&aux->work); @@ -2075,7 +2079,7 @@ static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) void bpf_prog_put(struct bpf_prog *prog) { - __bpf_prog_put(prog, true); + __bpf_prog_put(prog); } EXPORT_SYMBOL_GPL(bpf_prog_put); @@ -2117,11 +2121,11 @@ static void bpf_prog_get_stats(const struct bpf_prog *prog, st = per_cpu_ptr(prog->stats, cpu); do { - start = u64_stats_fetch_begin_irq(&st->syncp); + start = u64_stats_fetch_begin(&st->syncp); tnsecs = u64_stats_read(&st->nsecs); tcnt = u64_stats_read(&st->cnt); tmisses = u64_stats_read(&st->misses); - } while (u64_stats_fetch_retry_irq(&st->syncp, start)); + } while (u64_stats_fetch_retry(&st->syncp, start)); nsecs += tnsecs; cnt += tcnt; misses += tmisses; @@ -3504,9 +3508,9 @@ static int bpf_prog_attach(const union bpf_attr *attr) case BPF_PROG_TYPE_LSM: if (ptype == BPF_PROG_TYPE_LSM && prog->expected_attach_type != BPF_LSM_CGROUP) - return -EINVAL; - - ret = cgroup_bpf_prog_attach(attr, ptype, prog); + ret = -EINVAL; + else + ret = cgroup_bpf_prog_attach(attr, ptype, prog); break; default: ret = -EINVAL; @@ -4460,13 +4464,13 @@ put_file: #define BPF_MAP_BATCH_LAST_FIELD batch.flags -#define BPF_DO_BATCH(fn) \ +#define BPF_DO_BATCH(fn, ...) \ do { \ if (!fn) { \ err = -ENOTSUPP; \ goto err_put; \ } \ - err = fn(map, attr, uattr); \ + err = fn(__VA_ARGS__); \ } while (0) static int bpf_map_do_batch(const union bpf_attr *attr, @@ -4500,13 +4504,13 @@ static int bpf_map_do_batch(const union bpf_attr *attr, } if (cmd == BPF_MAP_LOOKUP_BATCH) - BPF_DO_BATCH(map->ops->map_lookup_batch); + BPF_DO_BATCH(map->ops->map_lookup_batch, map, attr, uattr); else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) - BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch); + BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch, map, attr, uattr); else if (cmd == BPF_MAP_UPDATE_BATCH) - BPF_DO_BATCH(map->ops->map_update_batch); + BPF_DO_BATCH(map->ops->map_update_batch, map, f.file, attr, uattr); else - BPF_DO_BATCH(map->ops->map_delete_batch); + BPF_DO_BATCH(map->ops->map_delete_batch, map, attr, uattr); err_put: if (has_write) bpf_map_write_active_dec(map); @@ -5133,13 +5137,14 @@ int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size) run_ctx.bpf_cookie = 0; run_ctx.saved_run_ctx = NULL; - if (!__bpf_prog_enter_sleepable(prog, &run_ctx)) { + if (!__bpf_prog_enter_sleepable_recur(prog, &run_ctx)) { /* recursion detected */ bpf_prog_put(prog); return -EBUSY; } attr->test.retval = bpf_prog_run(prog, (void *) (long) attr->test.ctx_in); - __bpf_prog_exit_sleepable(prog, 0 /* bpf_prog_run does runtime stats */, &run_ctx); + __bpf_prog_exit_sleepable_recur(prog, 0 /* bpf_prog_run does runtime stats */, + &run_ctx); bpf_prog_put(prog); return 0; #endif diff --git a/kernel/bpf/task_iter.c b/kernel/bpf/task_iter.c index c2a2182ce570..c4ab9d6cdbe9 100644 --- a/kernel/bpf/task_iter.c +++ b/kernel/bpf/task_iter.c @@ -438,6 +438,7 @@ struct bpf_iter_seq_task_vma_info { */ struct bpf_iter_seq_task_common common; struct task_struct *task; + struct mm_struct *mm; struct vm_area_struct *vma; u32 tid; unsigned long prev_vm_start; @@ -456,16 +457,19 @@ task_vma_seq_get_next(struct bpf_iter_seq_task_vma_info *info) enum bpf_task_vma_iter_find_op op; struct vm_area_struct *curr_vma; struct task_struct *curr_task; + struct mm_struct *curr_mm; u32 saved_tid = info->tid; /* If this function returns a non-NULL vma, it holds a reference to - * the task_struct, and holds read lock on vma->mm->mmap_lock. + * the task_struct, holds a refcount on mm->mm_users, and holds + * read lock on vma->mm->mmap_lock. * If this function returns NULL, it does not hold any reference or * lock. */ if (info->task) { curr_task = info->task; curr_vma = info->vma; + curr_mm = info->mm; /* In case of lock contention, drop mmap_lock to unblock * the writer. * @@ -504,13 +508,15 @@ task_vma_seq_get_next(struct bpf_iter_seq_task_vma_info *info) * 4.2) VMA2 and VMA2' covers different ranges, process * VMA2'. */ - if (mmap_lock_is_contended(curr_task->mm)) { + if (mmap_lock_is_contended(curr_mm)) { info->prev_vm_start = curr_vma->vm_start; info->prev_vm_end = curr_vma->vm_end; op = task_vma_iter_find_vma; - mmap_read_unlock(curr_task->mm); - if (mmap_read_lock_killable(curr_task->mm)) + mmap_read_unlock(curr_mm); + if (mmap_read_lock_killable(curr_mm)) { + mmput(curr_mm); goto finish; + } } else { op = task_vma_iter_next_vma; } @@ -535,42 +541,47 @@ again: op = task_vma_iter_find_vma; } - if (!curr_task->mm) + curr_mm = get_task_mm(curr_task); + if (!curr_mm) goto next_task; - if (mmap_read_lock_killable(curr_task->mm)) + if (mmap_read_lock_killable(curr_mm)) { + mmput(curr_mm); goto finish; + } } switch (op) { case task_vma_iter_first_vma: - curr_vma = find_vma(curr_task->mm, 0); + curr_vma = find_vma(curr_mm, 0); break; case task_vma_iter_next_vma: - curr_vma = find_vma(curr_task->mm, curr_vma->vm_end); + curr_vma = find_vma(curr_mm, curr_vma->vm_end); break; case task_vma_iter_find_vma: /* We dropped mmap_lock so it is necessary to use find_vma * to find the next vma. This is similar to the mechanism * in show_smaps_rollup(). */ - curr_vma = find_vma(curr_task->mm, info->prev_vm_end - 1); + curr_vma = find_vma(curr_mm, info->prev_vm_end - 1); /* case 1) and 4.2) above just use curr_vma */ /* check for case 2) or case 4.1) above */ if (curr_vma && curr_vma->vm_start == info->prev_vm_start && curr_vma->vm_end == info->prev_vm_end) - curr_vma = find_vma(curr_task->mm, curr_vma->vm_end); + curr_vma = find_vma(curr_mm, curr_vma->vm_end); break; } if (!curr_vma) { /* case 3) above, or case 2) 4.1) with vma->next == NULL */ - mmap_read_unlock(curr_task->mm); + mmap_read_unlock(curr_mm); + mmput(curr_mm); goto next_task; } info->task = curr_task; info->vma = curr_vma; + info->mm = curr_mm; return curr_vma; next_task: @@ -579,6 +590,7 @@ next_task: put_task_struct(curr_task); info->task = NULL; + info->mm = NULL; info->tid++; goto again; @@ -587,6 +599,7 @@ finish: put_task_struct(curr_task); info->task = NULL; info->vma = NULL; + info->mm = NULL; return NULL; } @@ -658,7 +671,9 @@ static void task_vma_seq_stop(struct seq_file *seq, void *v) */ info->prev_vm_start = ~0UL; info->prev_vm_end = info->vma->vm_end; - mmap_read_unlock(info->task->mm); + mmap_read_unlock(info->mm); + mmput(info->mm); + info->mm = NULL; put_task_struct(info->task); info->task = NULL; } diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c index bf0906e1e2b9..d0ed7d6f5eec 100644 --- a/kernel/bpf/trampoline.c +++ b/kernel/bpf/trampoline.c @@ -468,8 +468,7 @@ again: if (err < 0) goto out; - set_memory_ro((long)im->image, 1); - set_memory_x((long)im->image, 1); + set_memory_rox((long)im->image, 1); WARN_ON(tr->cur_image && tr->selector == 0); WARN_ON(!tr->cur_image && tr->selector); @@ -489,6 +488,10 @@ again: /* reset fops->func and fops->trampoline for re-register */ tr->fops->func = NULL; tr->fops->trampoline = 0; + + /* reset im->image memory attr for arch_prepare_bpf_trampoline */ + set_memory_nx((long)im->image, 1); + set_memory_rw((long)im->image, 1); goto again; } #endif @@ -864,7 +867,7 @@ static __always_inline u64 notrace bpf_prog_start_time(void) * [2..MAX_U64] - execute bpf prog and record execution time. * This is start time. */ -u64 notrace __bpf_prog_enter(struct bpf_prog *prog, struct bpf_tramp_run_ctx *run_ctx) +static u64 notrace __bpf_prog_enter_recur(struct bpf_prog *prog, struct bpf_tramp_run_ctx *run_ctx) __acquires(RCU) { rcu_read_lock(); @@ -901,7 +904,8 @@ static void notrace update_prog_stats(struct bpf_prog *prog, } } -void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start, struct bpf_tramp_run_ctx *run_ctx) +static void notrace __bpf_prog_exit_recur(struct bpf_prog *prog, u64 start, + struct bpf_tramp_run_ctx *run_ctx) __releases(RCU) { bpf_reset_run_ctx(run_ctx->saved_run_ctx); @@ -912,8 +916,8 @@ void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start, struct bpf_tramp_ rcu_read_unlock(); } -u64 notrace __bpf_prog_enter_lsm_cgroup(struct bpf_prog *prog, - struct bpf_tramp_run_ctx *run_ctx) +static u64 notrace __bpf_prog_enter_lsm_cgroup(struct bpf_prog *prog, + struct bpf_tramp_run_ctx *run_ctx) __acquires(RCU) { /* Runtime stats are exported via actual BPF_LSM_CGROUP @@ -927,8 +931,8 @@ u64 notrace __bpf_prog_enter_lsm_cgroup(struct bpf_prog *prog, return NO_START_TIME; } -void notrace __bpf_prog_exit_lsm_cgroup(struct bpf_prog *prog, u64 start, - struct bpf_tramp_run_ctx *run_ctx) +static void notrace __bpf_prog_exit_lsm_cgroup(struct bpf_prog *prog, u64 start, + struct bpf_tramp_run_ctx *run_ctx) __releases(RCU) { bpf_reset_run_ctx(run_ctx->saved_run_ctx); @@ -937,7 +941,8 @@ void notrace __bpf_prog_exit_lsm_cgroup(struct bpf_prog *prog, u64 start, rcu_read_unlock(); } -u64 notrace __bpf_prog_enter_sleepable(struct bpf_prog *prog, struct bpf_tramp_run_ctx *run_ctx) +u64 notrace __bpf_prog_enter_sleepable_recur(struct bpf_prog *prog, + struct bpf_tramp_run_ctx *run_ctx) { rcu_read_lock_trace(); migrate_disable(); @@ -953,8 +958,8 @@ u64 notrace __bpf_prog_enter_sleepable(struct bpf_prog *prog, struct bpf_tramp_r return bpf_prog_start_time(); } -void notrace __bpf_prog_exit_sleepable(struct bpf_prog *prog, u64 start, - struct bpf_tramp_run_ctx *run_ctx) +void notrace __bpf_prog_exit_sleepable_recur(struct bpf_prog *prog, u64 start, + struct bpf_tramp_run_ctx *run_ctx) { bpf_reset_run_ctx(run_ctx->saved_run_ctx); @@ -964,8 +969,30 @@ void notrace __bpf_prog_exit_sleepable(struct bpf_prog *prog, u64 start, rcu_read_unlock_trace(); } -u64 notrace __bpf_prog_enter_struct_ops(struct bpf_prog *prog, - struct bpf_tramp_run_ctx *run_ctx) +static u64 notrace __bpf_prog_enter_sleepable(struct bpf_prog *prog, + struct bpf_tramp_run_ctx *run_ctx) +{ + rcu_read_lock_trace(); + migrate_disable(); + might_fault(); + + run_ctx->saved_run_ctx = bpf_set_run_ctx(&run_ctx->run_ctx); + + return bpf_prog_start_time(); +} + +static void notrace __bpf_prog_exit_sleepable(struct bpf_prog *prog, u64 start, + struct bpf_tramp_run_ctx *run_ctx) +{ + bpf_reset_run_ctx(run_ctx->saved_run_ctx); + + update_prog_stats(prog, start); + migrate_enable(); + rcu_read_unlock_trace(); +} + +static u64 notrace __bpf_prog_enter(struct bpf_prog *prog, + struct bpf_tramp_run_ctx *run_ctx) __acquires(RCU) { rcu_read_lock(); @@ -976,8 +1003,8 @@ u64 notrace __bpf_prog_enter_struct_ops(struct bpf_prog *prog, return bpf_prog_start_time(); } -void notrace __bpf_prog_exit_struct_ops(struct bpf_prog *prog, u64 start, - struct bpf_tramp_run_ctx *run_ctx) +static void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start, + struct bpf_tramp_run_ctx *run_ctx) __releases(RCU) { bpf_reset_run_ctx(run_ctx->saved_run_ctx); @@ -997,6 +1024,36 @@ void notrace __bpf_tramp_exit(struct bpf_tramp_image *tr) percpu_ref_put(&tr->pcref); } +bpf_trampoline_enter_t bpf_trampoline_enter(const struct bpf_prog *prog) +{ + bool sleepable = prog->aux->sleepable; + + if (bpf_prog_check_recur(prog)) + return sleepable ? __bpf_prog_enter_sleepable_recur : + __bpf_prog_enter_recur; + + if (resolve_prog_type(prog) == BPF_PROG_TYPE_LSM && + prog->expected_attach_type == BPF_LSM_CGROUP) + return __bpf_prog_enter_lsm_cgroup; + + return sleepable ? __bpf_prog_enter_sleepable : __bpf_prog_enter; +} + +bpf_trampoline_exit_t bpf_trampoline_exit(const struct bpf_prog *prog) +{ + bool sleepable = prog->aux->sleepable; + + if (bpf_prog_check_recur(prog)) + return sleepable ? __bpf_prog_exit_sleepable_recur : + __bpf_prog_exit_recur; + + if (resolve_prog_type(prog) == BPF_PROG_TYPE_LSM && + prog->expected_attach_type == BPF_LSM_CGROUP) + return __bpf_prog_exit_lsm_cgroup; + + return sleepable ? __bpf_prog_exit_sleepable : __bpf_prog_exit; +} + int __weak arch_prepare_bpf_trampoline(struct bpf_tramp_image *tr, void *image, void *image_end, const struct btf_func_model *m, u32 flags, diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 264b3dc714cc..7ee218827259 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -262,7 +262,7 @@ struct bpf_call_arg_meta { struct btf *ret_btf; u32 ret_btf_id; u32 subprogno; - struct bpf_map_value_off_desc *kptr_off_desc; + struct btf_field *kptr_field; u8 uninit_dynptr_regno; }; @@ -451,17 +451,29 @@ static bool reg_type_not_null(enum bpf_reg_type type) type == PTR_TO_SOCK_COMMON; } -static bool reg_may_point_to_spin_lock(const struct bpf_reg_state *reg) +static bool type_is_ptr_alloc_obj(u32 type) { - return reg->type == PTR_TO_MAP_VALUE && - map_value_has_spin_lock(reg->map_ptr); + return base_type(type) == PTR_TO_BTF_ID && type_flag(type) & MEM_ALLOC; } -static bool reg_type_may_be_refcounted_or_null(enum bpf_reg_type type) +static struct btf_record *reg_btf_record(const struct bpf_reg_state *reg) { - type = base_type(type); - return type == PTR_TO_SOCKET || type == PTR_TO_TCP_SOCK || - type == PTR_TO_MEM || type == PTR_TO_BTF_ID; + struct btf_record *rec = NULL; + struct btf_struct_meta *meta; + + if (reg->type == PTR_TO_MAP_VALUE) { + rec = reg->map_ptr->record; + } else if (type_is_ptr_alloc_obj(reg->type)) { + meta = btf_find_struct_meta(reg->btf, reg->btf_id); + if (meta) + rec = meta->record; + } + return rec; +} + +static bool reg_may_point_to_spin_lock(const struct bpf_reg_state *reg) +{ + return btf_record_has_field(reg_btf_record(reg), BPF_SPIN_LOCK); } static bool type_is_rdonly_mem(u32 type) @@ -511,6 +523,23 @@ static bool is_dynptr_ref_function(enum bpf_func_id func_id) return func_id == BPF_FUNC_dynptr_data; } +static bool is_callback_calling_function(enum bpf_func_id func_id) +{ + return func_id == BPF_FUNC_for_each_map_elem || + func_id == BPF_FUNC_timer_set_callback || + func_id == BPF_FUNC_find_vma || + func_id == BPF_FUNC_loop || + func_id == BPF_FUNC_user_ringbuf_drain; +} + +static bool is_storage_get_function(enum bpf_func_id func_id) +{ + return func_id == BPF_FUNC_sk_storage_get || + func_id == BPF_FUNC_inode_storage_get || + func_id == BPF_FUNC_task_storage_get || + func_id == BPF_FUNC_cgrp_storage_get; +} + static bool helper_multiple_ref_obj_use(enum bpf_func_id func_id, const struct bpf_map *map) { @@ -541,7 +570,7 @@ static bool is_cmpxchg_insn(const struct bpf_insn *insn) static const char *reg_type_str(struct bpf_verifier_env *env, enum bpf_reg_type type) { - char postfix[16] = {0}, prefix[32] = {0}; + char postfix[16] = {0}, prefix[64] = {0}; static const char * const str[] = { [NOT_INIT] = "?", [SCALAR_VALUE] = "scalar", @@ -563,7 +592,7 @@ static const char *reg_type_str(struct bpf_verifier_env *env, [PTR_TO_BUF] = "buf", [PTR_TO_FUNC] = "func", [PTR_TO_MAP_KEY] = "map_key", - [PTR_TO_DYNPTR] = "dynptr_ptr", + [CONST_PTR_TO_DYNPTR] = "dynptr_ptr", }; if (type & PTR_MAYBE_NULL) { @@ -573,16 +602,15 @@ static const char *reg_type_str(struct bpf_verifier_env *env, strncpy(postfix, "_or_null", 16); } - if (type & MEM_RDONLY) - strncpy(prefix, "rdonly_", 32); - if (type & MEM_ALLOC) - strncpy(prefix, "alloc_", 32); - if (type & MEM_USER) - strncpy(prefix, "user_", 32); - if (type & MEM_PERCPU) - strncpy(prefix, "percpu_", 32); - if (type & PTR_UNTRUSTED) - strncpy(prefix, "untrusted_", 32); + snprintf(prefix, sizeof(prefix), "%s%s%s%s%s%s%s", + type & MEM_RDONLY ? "rdonly_" : "", + type & MEM_RINGBUF ? "ringbuf_" : "", + type & MEM_USER ? "user_" : "", + type & MEM_PERCPU ? "percpu_" : "", + type & MEM_RCU ? "rcu_" : "", + type & PTR_UNTRUSTED ? "untrusted_" : "", + type & PTR_TRUSTED ? "trusted_" : "" + ); snprintf(env->type_str_buf, TYPE_STR_BUF_LEN, "%s%s%s", prefix, str[base_type(type)], postfix); @@ -697,6 +725,28 @@ static bool dynptr_type_refcounted(enum bpf_dynptr_type type) return type == BPF_DYNPTR_TYPE_RINGBUF; } +static void __mark_dynptr_reg(struct bpf_reg_state *reg, + enum bpf_dynptr_type type, + bool first_slot); + +static void __mark_reg_not_init(const struct bpf_verifier_env *env, + struct bpf_reg_state *reg); + +static void mark_dynptr_stack_regs(struct bpf_reg_state *sreg1, + struct bpf_reg_state *sreg2, + enum bpf_dynptr_type type) +{ + __mark_dynptr_reg(sreg1, type, true); + __mark_dynptr_reg(sreg2, type, false); +} + +static void mark_dynptr_cb_reg(struct bpf_reg_state *reg, + enum bpf_dynptr_type type) +{ + __mark_dynptr_reg(reg, type, true); +} + + static int mark_stack_slots_dynptr(struct bpf_verifier_env *env, struct bpf_reg_state *reg, enum bpf_arg_type arg_type, int insn_idx) { @@ -718,9 +768,8 @@ static int mark_stack_slots_dynptr(struct bpf_verifier_env *env, struct bpf_reg_ if (type == BPF_DYNPTR_TYPE_INVALID) return -EINVAL; - state->stack[spi].spilled_ptr.dynptr.first_slot = true; - state->stack[spi].spilled_ptr.dynptr.type = type; - state->stack[spi - 1].spilled_ptr.dynptr.type = type; + mark_dynptr_stack_regs(&state->stack[spi].spilled_ptr, + &state->stack[spi - 1].spilled_ptr, type); if (dynptr_type_refcounted(type)) { /* The id is used to track proper releasing */ @@ -728,8 +777,8 @@ static int mark_stack_slots_dynptr(struct bpf_verifier_env *env, struct bpf_reg_ if (id < 0) return id; - state->stack[spi].spilled_ptr.id = id; - state->stack[spi - 1].spilled_ptr.id = id; + state->stack[spi].spilled_ptr.ref_obj_id = id; + state->stack[spi - 1].spilled_ptr.ref_obj_id = id; } return 0; @@ -751,25 +800,23 @@ static int unmark_stack_slots_dynptr(struct bpf_verifier_env *env, struct bpf_re } /* Invalidate any slices associated with this dynptr */ - if (dynptr_type_refcounted(state->stack[spi].spilled_ptr.dynptr.type)) { - release_reference(env, state->stack[spi].spilled_ptr.id); - state->stack[spi].spilled_ptr.id = 0; - state->stack[spi - 1].spilled_ptr.id = 0; - } - - state->stack[spi].spilled_ptr.dynptr.first_slot = false; - state->stack[spi].spilled_ptr.dynptr.type = 0; - state->stack[spi - 1].spilled_ptr.dynptr.type = 0; + if (dynptr_type_refcounted(state->stack[spi].spilled_ptr.dynptr.type)) + WARN_ON_ONCE(release_reference(env, state->stack[spi].spilled_ptr.ref_obj_id)); + __mark_reg_not_init(env, &state->stack[spi].spilled_ptr); + __mark_reg_not_init(env, &state->stack[spi - 1].spilled_ptr); return 0; } static bool is_dynptr_reg_valid_uninit(struct bpf_verifier_env *env, struct bpf_reg_state *reg) { struct bpf_func_state *state = func(env, reg); - int spi = get_spi(reg->off); - int i; + int spi, i; + if (reg->type == CONST_PTR_TO_DYNPTR) + return false; + + spi = get_spi(reg->off); if (!is_spi_bounds_valid(state, spi, BPF_DYNPTR_NR_SLOTS)) return true; @@ -782,13 +829,17 @@ static bool is_dynptr_reg_valid_uninit(struct bpf_verifier_env *env, struct bpf_ return true; } -bool is_dynptr_reg_valid_init(struct bpf_verifier_env *env, - struct bpf_reg_state *reg) +static bool is_dynptr_reg_valid_init(struct bpf_verifier_env *env, struct bpf_reg_state *reg) { struct bpf_func_state *state = func(env, reg); - int spi = get_spi(reg->off); + int spi; int i; + /* This already represents first slot of initialized bpf_dynptr */ + if (reg->type == CONST_PTR_TO_DYNPTR) + return true; + + spi = get_spi(reg->off); if (!is_spi_bounds_valid(state, spi, BPF_DYNPTR_NR_SLOTS) || !state->stack[spi].spilled_ptr.dynptr.first_slot) return false; @@ -802,21 +853,24 @@ bool is_dynptr_reg_valid_init(struct bpf_verifier_env *env, return true; } -bool is_dynptr_type_expected(struct bpf_verifier_env *env, - struct bpf_reg_state *reg, - enum bpf_arg_type arg_type) +static bool is_dynptr_type_expected(struct bpf_verifier_env *env, struct bpf_reg_state *reg, + enum bpf_arg_type arg_type) { struct bpf_func_state *state = func(env, reg); enum bpf_dynptr_type dynptr_type; - int spi = get_spi(reg->off); + int spi; /* ARG_PTR_TO_DYNPTR takes any type of dynptr */ if (arg_type == ARG_PTR_TO_DYNPTR) return true; dynptr_type = arg_to_dynptr_type(arg_type); - - return state->stack[spi].spilled_ptr.dynptr.type == dynptr_type; + if (reg->type == CONST_PTR_TO_DYNPTR) { + return reg->dynptr.type == dynptr_type; + } else { + spi = get_spi(reg->off); + return state->stack[spi].spilled_ptr.dynptr.type == dynptr_type; + } } /* The reg state of a pointer or a bounded scalar was saved when @@ -875,7 +929,7 @@ static void print_verifier_state(struct bpf_verifier_env *env, if (reg->id) verbose_a("id=%d", reg->id); - if (reg_type_may_be_refcounted_or_null(t) && reg->ref_obj_id) + if (reg->ref_obj_id) verbose_a("ref_obj_id=%d", reg->ref_obj_id); if (t != SCALAR_VALUE) verbose_a("off=%d", reg->off); @@ -1000,6 +1054,8 @@ static void print_insn_state(struct bpf_verifier_env *env, */ static void *copy_array(void *dst, const void *src, size_t n, size_t size, gfp_t flags) { + size_t alloc_bytes; + void *orig = dst; size_t bytes; if (ZERO_OR_NULL_PTR(src)) @@ -1008,11 +1064,11 @@ static void *copy_array(void *dst, const void *src, size_t n, size_t size, gfp_t if (unlikely(check_mul_overflow(n, size, &bytes))) return NULL; - if (ksize(dst) < bytes) { - kfree(dst); - dst = kmalloc_track_caller(bytes, flags); - if (!dst) - return NULL; + alloc_bytes = max(ksize(orig), kmalloc_size_roundup(bytes)); + dst = krealloc(orig, alloc_bytes, flags); + if (!dst) { + kfree(orig); + return NULL; } memcpy(dst, src, bytes); @@ -1027,12 +1083,14 @@ out: */ static void *realloc_array(void *arr, size_t old_n, size_t new_n, size_t size) { + size_t alloc_size; void *new_arr; if (!new_n || old_n == new_n) goto out; - new_arr = krealloc_array(arr, new_n, size, GFP_KERNEL); + alloc_size = kmalloc_size_roundup(size_mul(new_n, size)); + new_arr = krealloc(arr, alloc_size, GFP_KERNEL); if (!new_arr) { kfree(arr); return NULL; @@ -1204,8 +1262,10 @@ static int copy_verifier_state(struct bpf_verifier_state *dst_state, dst_state->frame[i] = NULL; } dst_state->speculative = src->speculative; + dst_state->active_rcu_lock = src->active_rcu_lock; dst_state->curframe = src->curframe; - dst_state->active_spin_lock = src->active_spin_lock; + dst_state->active_lock.ptr = src->active_lock.ptr; + dst_state->active_lock.id = src->active_lock.id; dst_state->branches = src->branches; dst_state->parent = src->parent; dst_state->first_insn_idx = src->first_insn_idx; @@ -1324,9 +1384,6 @@ static const int caller_saved[CALLER_SAVED_REGS] = { BPF_REG_0, BPF_REG_1, BPF_REG_2, BPF_REG_3, BPF_REG_4, BPF_REG_5 }; -static void __mark_reg_not_init(const struct bpf_verifier_env *env, - struct bpf_reg_state *reg); - /* This helper doesn't clear reg->id */ static void ___mark_reg_known(struct bpf_reg_state *reg, u64 imm) { @@ -1389,6 +1446,19 @@ static void mark_reg_known_zero(struct bpf_verifier_env *env, __mark_reg_known_zero(regs + regno); } +static void __mark_dynptr_reg(struct bpf_reg_state *reg, enum bpf_dynptr_type type, + bool first_slot) +{ + /* reg->type has no meaning for STACK_DYNPTR, but when we set reg for + * callback arguments, it does need to be CONST_PTR_TO_DYNPTR, so simply + * set it unconditionally as it is ignored for STACK_DYNPTR anyway. + */ + __mark_reg_known_zero(reg); + reg->type = CONST_PTR_TO_DYNPTR; + reg->dynptr.type = type; + reg->dynptr.first_slot = first_slot; +} + static void mark_ptr_not_null_reg(struct bpf_reg_state *reg) { if (base_type(reg->type) == PTR_TO_MAP_VALUE) { @@ -1400,7 +1470,7 @@ static void mark_ptr_not_null_reg(struct bpf_reg_state *reg) /* transfer reg's id which is unique for every map_lookup_elem * as UID of the inner map. */ - if (map_value_has_timer(map->inner_map_meta)) + if (btf_record_has_field(map->inner_map_meta->record, BPF_TIMER)) reg->map_uid = reg->id; } else if (map->map_type == BPF_MAP_TYPE_XSKMAP) { reg->type = PTR_TO_XDP_SOCK; @@ -1689,7 +1759,7 @@ static void __mark_reg_unknown(const struct bpf_verifier_env *env, reg->type = SCALAR_VALUE; reg->var_off = tnum_unknown; reg->frameno = 0; - reg->precise = env->subprog_cnt > 1 || !env->bpf_capable; + reg->precise = !env->bpf_capable; __mark_reg_unbounded(reg); } @@ -2498,15 +2568,30 @@ static int check_reg_arg(struct bpf_verifier_env *env, u32 regno, return 0; } +static void mark_jmp_point(struct bpf_verifier_env *env, int idx) +{ + env->insn_aux_data[idx].jmp_point = true; +} + +static bool is_jmp_point(struct bpf_verifier_env *env, int insn_idx) +{ + return env->insn_aux_data[insn_idx].jmp_point; +} + /* for any branch, call, exit record the history of jmps in the given state */ static int push_jmp_history(struct bpf_verifier_env *env, struct bpf_verifier_state *cur) { u32 cnt = cur->jmp_history_cnt; struct bpf_idx_pair *p; + size_t alloc_size; + + if (!is_jmp_point(env, env->insn_idx)) + return 0; cnt++; - p = krealloc(cur->jmp_history, cnt * sizeof(*p), GFP_USER); + alloc_size = kmalloc_size_roundup(size_mul(cnt, sizeof(*p))); + p = krealloc(cur->jmp_history, alloc_size, GFP_USER); if (!p) return -ENOMEM; p[cnt - 1].idx = env->insn_idx; @@ -2658,6 +2743,17 @@ static int backtrack_insn(struct bpf_verifier_env *env, int idx, if (opcode == BPF_CALL) { if (insn->src_reg == BPF_PSEUDO_CALL) return -ENOTSUPP; + /* BPF helpers that invoke callback subprogs are + * equivalent to BPF_PSEUDO_CALL above + */ + if (insn->src_reg == 0 && is_callback_calling_function(insn->imm)) + return -ENOTSUPP; + /* kfunc with imm==0 is invalid and fixup_kfunc_call will + * catch this error later. Make backtracking conservative + * with ENOTSUPP. + */ + if (insn->src_reg == BPF_PSEUDO_KFUNC_CALL && insn->imm == 0) + return -ENOTSUPP; /* regular helper call sets R0 */ *reg_mask &= ~1; if (*reg_mask & 0x3f) { @@ -2747,8 +2843,11 @@ static void mark_all_scalars_precise(struct bpf_verifier_env *env, /* big hammer: mark all scalars precise in this path. * pop_stack may still get !precise scalars. + * We also skip current state and go straight to first parent state, + * because precision markings in current non-checkpointed state are + * not needed. See why in the comment in __mark_chain_precision below. */ - for (; st; st = st->parent) + for (st = st->parent; st; st = st->parent) { for (i = 0; i <= st->curframe; i++) { func = st->frame[i]; for (j = 0; j < BPF_REG_FP; j++) { @@ -2766,9 +2865,122 @@ static void mark_all_scalars_precise(struct bpf_verifier_env *env, reg->precise = true; } } + } } -static int __mark_chain_precision(struct bpf_verifier_env *env, int regno, +static void mark_all_scalars_imprecise(struct bpf_verifier_env *env, struct bpf_verifier_state *st) +{ + struct bpf_func_state *func; + struct bpf_reg_state *reg; + int i, j; + + for (i = 0; i <= st->curframe; i++) { + func = st->frame[i]; + for (j = 0; j < BPF_REG_FP; j++) { + reg = &func->regs[j]; + if (reg->type != SCALAR_VALUE) + continue; + reg->precise = false; + } + for (j = 0; j < func->allocated_stack / BPF_REG_SIZE; j++) { + if (!is_spilled_reg(&func->stack[j])) + continue; + reg = &func->stack[j].spilled_ptr; + if (reg->type != SCALAR_VALUE) + continue; + reg->precise = false; + } + } +} + +/* + * __mark_chain_precision() backtracks BPF program instruction sequence and + * chain of verifier states making sure that register *regno* (if regno >= 0) + * and/or stack slot *spi* (if spi >= 0) are marked as precisely tracked + * SCALARS, as well as any other registers and slots that contribute to + * a tracked state of given registers/stack slots, depending on specific BPF + * assembly instructions (see backtrack_insns() for exact instruction handling + * logic). This backtracking relies on recorded jmp_history and is able to + * traverse entire chain of parent states. This process ends only when all the + * necessary registers/slots and their transitive dependencies are marked as + * precise. + * + * One important and subtle aspect is that precise marks *do not matter* in + * the currently verified state (current state). It is important to understand + * why this is the case. + * + * First, note that current state is the state that is not yet "checkpointed", + * i.e., it is not yet put into env->explored_states, and it has no children + * states as well. It's ephemeral, and can end up either a) being discarded if + * compatible explored state is found at some point or BPF_EXIT instruction is + * reached or b) checkpointed and put into env->explored_states, branching out + * into one or more children states. + * + * In the former case, precise markings in current state are completely + * ignored by state comparison code (see regsafe() for details). Only + * checkpointed ("old") state precise markings are important, and if old + * state's register/slot is precise, regsafe() assumes current state's + * register/slot as precise and checks value ranges exactly and precisely. If + * states turn out to be compatible, current state's necessary precise + * markings and any required parent states' precise markings are enforced + * after the fact with propagate_precision() logic, after the fact. But it's + * important to realize that in this case, even after marking current state + * registers/slots as precise, we immediately discard current state. So what + * actually matters is any of the precise markings propagated into current + * state's parent states, which are always checkpointed (due to b) case above). + * As such, for scenario a) it doesn't matter if current state has precise + * markings set or not. + * + * Now, for the scenario b), checkpointing and forking into child(ren) + * state(s). Note that before current state gets to checkpointing step, any + * processed instruction always assumes precise SCALAR register/slot + * knowledge: if precise value or range is useful to prune jump branch, BPF + * verifier takes this opportunity enthusiastically. Similarly, when + * register's value is used to calculate offset or memory address, exact + * knowledge of SCALAR range is assumed, checked, and enforced. So, similar to + * what we mentioned above about state comparison ignoring precise markings + * during state comparison, BPF verifier ignores and also assumes precise + * markings *at will* during instruction verification process. But as verifier + * assumes precision, it also propagates any precision dependencies across + * parent states, which are not yet finalized, so can be further restricted + * based on new knowledge gained from restrictions enforced by their children + * states. This is so that once those parent states are finalized, i.e., when + * they have no more active children state, state comparison logic in + * is_state_visited() would enforce strict and precise SCALAR ranges, if + * required for correctness. + * + * To build a bit more intuition, note also that once a state is checkpointed, + * the path we took to get to that state is not important. This is crucial + * property for state pruning. When state is checkpointed and finalized at + * some instruction index, it can be correctly and safely used to "short + * circuit" any *compatible* state that reaches exactly the same instruction + * index. I.e., if we jumped to that instruction from a completely different + * code path than original finalized state was derived from, it doesn't + * matter, current state can be discarded because from that instruction + * forward having a compatible state will ensure we will safely reach the + * exit. States describe preconditions for further exploration, but completely + * forget the history of how we got here. + * + * This also means that even if we needed precise SCALAR range to get to + * finalized state, but from that point forward *that same* SCALAR register is + * never used in a precise context (i.e., it's precise value is not needed for + * correctness), it's correct and safe to mark such register as "imprecise" + * (i.e., precise marking set to false). This is what we rely on when we do + * not set precise marking in current state. If no child state requires + * precision for any given SCALAR register, it's safe to dictate that it can + * be imprecise. If any child state does require this register to be precise, + * we'll mark it precise later retroactively during precise markings + * propagation from child state to parent states. + * + * Skipping precise marking setting in current state is a mild version of + * relying on the above observation. But we can utilize this property even + * more aggressively by proactively forgetting any precise marking in the + * current state (which we inherited from the parent state), right before we + * checkpoint it and branch off into new child state. This is done by + * mark_all_scalars_imprecise() to hopefully get more permissive and generic + * finalized states which help in short circuiting more future states. + */ +static int __mark_chain_precision(struct bpf_verifier_env *env, int frame, int regno, int spi) { struct bpf_verifier_state *st = env->cur_state; @@ -2785,18 +2997,18 @@ static int __mark_chain_precision(struct bpf_verifier_env *env, int regno, if (!env->bpf_capable) return 0; - func = st->frame[st->curframe]; + /* Do sanity checks against current state of register and/or stack + * slot, but don't set precise flag in current state, as precision + * tracking in the current state is unnecessary. + */ + func = st->frame[frame]; if (regno >= 0) { reg = &func->regs[regno]; if (reg->type != SCALAR_VALUE) { WARN_ONCE(1, "backtracing misuse"); return -EFAULT; } - if (!reg->precise) - new_marks = true; - else - reg_mask = 0; - reg->precise = true; + new_marks = true; } while (spi >= 0) { @@ -2809,11 +3021,7 @@ static int __mark_chain_precision(struct bpf_verifier_env *env, int regno, stack_mask = 0; break; } - if (!reg->precise) - new_marks = true; - else - stack_mask = 0; - reg->precise = true; + new_marks = true; break; } @@ -2821,12 +3029,42 @@ static int __mark_chain_precision(struct bpf_verifier_env *env, int regno, return 0; if (!reg_mask && !stack_mask) return 0; + for (;;) { DECLARE_BITMAP(mask, 64); u32 history = st->jmp_history_cnt; if (env->log.level & BPF_LOG_LEVEL2) verbose(env, "last_idx %d first_idx %d\n", last_idx, first_idx); + + if (last_idx < 0) { + /* we are at the entry into subprog, which + * is expected for global funcs, but only if + * requested precise registers are R1-R5 + * (which are global func's input arguments) + */ + if (st->curframe == 0 && + st->frame[0]->subprogno > 0 && + st->frame[0]->callsite == BPF_MAIN_FUNC && + stack_mask == 0 && (reg_mask & ~0x3e) == 0) { + bitmap_from_u64(mask, reg_mask); + for_each_set_bit(i, mask, 32) { + reg = &st->frame[0]->regs[i]; + if (reg->type != SCALAR_VALUE) { + reg_mask &= ~(1u << i); + continue; + } + reg->precise = true; + } + return 0; + } + + verbose(env, "BUG backtracing func entry subprog %d reg_mask %x stack_mask %llx\n", + st->frame[0]->subprogno, reg_mask, stack_mask); + WARN_ONCE(1, "verifier backtracking bug"); + return -EFAULT; + } + for (i = last_idx;;) { if (skip_first) { err = 0; @@ -2866,7 +3104,7 @@ static int __mark_chain_precision(struct bpf_verifier_env *env, int regno, break; new_marks = false; - func = st->frame[st->curframe]; + func = st->frame[frame]; bitmap_from_u64(mask, reg_mask); for_each_set_bit(i, mask, 32) { reg = &func->regs[i]; @@ -2932,12 +3170,17 @@ static int __mark_chain_precision(struct bpf_verifier_env *env, int regno, int mark_chain_precision(struct bpf_verifier_env *env, int regno) { - return __mark_chain_precision(env, regno, -1); + return __mark_chain_precision(env, env->cur_state->curframe, regno, -1); +} + +static int mark_chain_precision_frame(struct bpf_verifier_env *env, int frame, int regno) +{ + return __mark_chain_precision(env, frame, regno, -1); } -static int mark_chain_precision_stack(struct bpf_verifier_env *env, int spi) +static int mark_chain_precision_stack_frame(struct bpf_verifier_env *env, int frame, int spi) { - return __mark_chain_precision(env, -1, spi); + return __mark_chain_precision(env, frame, -1, spi); } static bool is_spillable_regtype(enum bpf_reg_type type) @@ -3000,13 +3243,24 @@ static bool __is_pointer_value(bool allow_ptr_leaks, return reg->type != SCALAR_VALUE; } +/* Copy src state preserving dst->parent and dst->live fields */ +static void copy_register_state(struct bpf_reg_state *dst, const struct bpf_reg_state *src) +{ + struct bpf_reg_state *parent = dst->parent; + enum bpf_reg_liveness live = dst->live; + + *dst = *src; + dst->parent = parent; + dst->live = live; +} + static void save_register_state(struct bpf_func_state *state, int spi, struct bpf_reg_state *reg, int size) { int i; - state->stack[spi].spilled_ptr = *reg; + copy_register_state(&state->stack[spi].spilled_ptr, reg); if (size == BPF_REG_SIZE) state->stack[spi].spilled_ptr.live |= REG_LIVE_WRITTEN; @@ -3052,7 +3306,9 @@ static int check_stack_write_fixed_off(struct bpf_verifier_env *env, bool sanitize = reg && is_spillable_regtype(reg->type); for (i = 0; i < size; i++) { - if (state->stack[spi].slot_type[i] == STACK_INVALID) { + u8 type = state->stack[spi].slot_type[i]; + + if (type != STACK_MISC && type != STACK_ZERO) { sanitize = true; break; } @@ -3186,14 +3442,17 @@ static int check_stack_write_var_off(struct bpf_verifier_env *env, stype = &state->stack[spi].slot_type[slot % BPF_REG_SIZE]; mark_stack_slot_scratched(env, spi); - if (!env->allow_ptr_leaks - && *stype != NOT_INIT - && *stype != SCALAR_VALUE) { - /* Reject the write if there's are spilled pointers in - * range. If we didn't reject here, the ptr status - * would be erased below (even though not all slots are - * actually overwritten), possibly opening the door to - * leaks. + if (!env->allow_ptr_leaks && *stype != STACK_MISC && *stype != STACK_ZERO) { + /* Reject the write if range we may write to has not + * been initialized beforehand. If we didn't reject + * here, the ptr status would be erased below (even + * though not all slots are actually overwritten), + * possibly opening the door to leaks. + * + * We do however catch STACK_INVALID case below, and + * only allow reading possibly uninitialized memory + * later for CAP_PERFMON, as the write may not happen to + * that slot. */ verbose(env, "spilled ptr in range of var-offset stack write; insn %d, ptr off: %d", insn_idx, i); @@ -3329,7 +3588,7 @@ static int check_stack_read_fixed_off(struct bpf_verifier_env *env, */ s32 subreg_def = state->regs[dst_regno].subreg_def; - state->regs[dst_regno] = *reg; + copy_register_state(&state->regs[dst_regno], reg); state->regs[dst_regno].subreg_def = subreg_def; } else { for (i = 0; i < size; i++) { @@ -3350,7 +3609,7 @@ static int check_stack_read_fixed_off(struct bpf_verifier_env *env, if (dst_regno >= 0) { /* restore register state from stack */ - state->regs[dst_regno] = *reg; + copy_register_state(&state->regs[dst_regno], reg); /* mark reg as written since spilled pointer state likely * has its liveness marks cleared by is_state_visited() * which resets stack/reg liveness for state transitions @@ -3683,15 +3942,15 @@ int check_ptr_off_reg(struct bpf_verifier_env *env, } static int map_kptr_match_type(struct bpf_verifier_env *env, - struct bpf_map_value_off_desc *off_desc, + struct btf_field *kptr_field, struct bpf_reg_state *reg, u32 regno) { - const char *targ_name = kernel_type_name(off_desc->kptr.btf, off_desc->kptr.btf_id); - int perm_flags = PTR_MAYBE_NULL; + const char *targ_name = kernel_type_name(kptr_field->kptr.btf, kptr_field->kptr.btf_id); + int perm_flags = PTR_MAYBE_NULL | PTR_TRUSTED; const char *reg_name = ""; /* Only unreferenced case accepts untrusted pointers */ - if (off_desc->type == BPF_KPTR_UNREF) + if (kptr_field->type == BPF_KPTR_UNREF) perm_flags |= PTR_UNTRUSTED; if (base_type(reg->type) != PTR_TO_BTF_ID || (type_flag(reg->type) & ~perm_flags)) @@ -3738,15 +3997,15 @@ static int map_kptr_match_type(struct bpf_verifier_env *env, * strict mode to true for type match. */ if (!btf_struct_ids_match(&env->log, reg->btf, reg->btf_id, reg->off, - off_desc->kptr.btf, off_desc->kptr.btf_id, - off_desc->type == BPF_KPTR_REF)) + kptr_field->kptr.btf, kptr_field->kptr.btf_id, + kptr_field->type == BPF_KPTR_REF)) goto bad_type; return 0; bad_type: verbose(env, "invalid kptr access, R%d type=%s%s ", regno, reg_type_str(env, reg->type), reg_name); verbose(env, "expected=%s%s", reg_type_str(env, PTR_TO_BTF_ID), targ_name); - if (off_desc->type == BPF_KPTR_UNREF) + if (kptr_field->type == BPF_KPTR_UNREF) verbose(env, " or %s%s\n", reg_type_str(env, PTR_TO_BTF_ID | PTR_UNTRUSTED), targ_name); else @@ -3756,7 +4015,7 @@ bad_type: static int check_map_kptr_access(struct bpf_verifier_env *env, u32 regno, int value_regno, int insn_idx, - struct bpf_map_value_off_desc *off_desc) + struct btf_field *kptr_field) { struct bpf_insn *insn = &env->prog->insnsi[insn_idx]; int class = BPF_CLASS(insn->code); @@ -3766,7 +4025,7 @@ static int check_map_kptr_access(struct bpf_verifier_env *env, u32 regno, * - Reject cases where variable offset may touch kptr * - size of access (must be BPF_DW) * - tnum_is_const(reg->var_off) - * - off_desc->offset == off + reg->var_off.value + * - kptr_field->offset == off + reg->var_off.value */ /* Only BPF_[LDX,STX,ST] | BPF_MEM | BPF_DW is supported */ if (BPF_MODE(insn->code) != BPF_MEM) { @@ -3777,7 +4036,7 @@ static int check_map_kptr_access(struct bpf_verifier_env *env, u32 regno, /* We only allow loading referenced kptr, since it will be marked as * untrusted, similar to unreferenced kptr. */ - if (class != BPF_LDX && off_desc->type == BPF_KPTR_REF) { + if (class != BPF_LDX && kptr_field->type == BPF_KPTR_REF) { verbose(env, "store to referenced kptr disallowed\n"); return -EACCES; } @@ -3787,19 +4046,19 @@ static int check_map_kptr_access(struct bpf_verifier_env *env, u32 regno, /* We can simply mark the value_regno receiving the pointer * value from map as PTR_TO_BTF_ID, with the correct type. */ - mark_btf_ld_reg(env, cur_regs(env), value_regno, PTR_TO_BTF_ID, off_desc->kptr.btf, - off_desc->kptr.btf_id, PTR_MAYBE_NULL | PTR_UNTRUSTED); + mark_btf_ld_reg(env, cur_regs(env), value_regno, PTR_TO_BTF_ID, kptr_field->kptr.btf, + kptr_field->kptr.btf_id, PTR_MAYBE_NULL | PTR_UNTRUSTED); /* For mark_ptr_or_null_reg */ val_reg->id = ++env->id_gen; } else if (class == BPF_STX) { val_reg = reg_state(env, value_regno); if (!register_is_null(val_reg) && - map_kptr_match_type(env, off_desc, val_reg, value_regno)) + map_kptr_match_type(env, kptr_field, val_reg, value_regno)) return -EACCES; } else if (class == BPF_ST) { if (insn->imm) { verbose(env, "BPF_ST imm must be 0 when storing to kptr at off=%u\n", - off_desc->offset); + kptr_field->offset); return -EACCES; } } else { @@ -3818,45 +4077,30 @@ static int check_map_access(struct bpf_verifier_env *env, u32 regno, struct bpf_func_state *state = vstate->frame[vstate->curframe]; struct bpf_reg_state *reg = &state->regs[regno]; struct bpf_map *map = reg->map_ptr; - int err; + struct btf_record *rec; + int err, i; err = check_mem_region_access(env, regno, off, size, map->value_size, zero_size_allowed); if (err) return err; - if (map_value_has_spin_lock(map)) { - u32 lock = map->spin_lock_off; + if (IS_ERR_OR_NULL(map->record)) + return 0; + rec = map->record; + for (i = 0; i < rec->cnt; i++) { + struct btf_field *field = &rec->fields[i]; + u32 p = field->offset; - /* if any part of struct bpf_spin_lock can be touched by - * load/store reject this program. - * To check that [x1, x2) overlaps with [y1, y2) + /* If any part of a field can be touched by load/store, reject + * this program. To check that [x1, x2) overlaps with [y1, y2), * it is sufficient to check x1 < y2 && y1 < x2. */ - if (reg->smin_value + off < lock + sizeof(struct bpf_spin_lock) && - lock < reg->umax_value + off + size) { - verbose(env, "bpf_spin_lock cannot be accessed directly by load/store\n"); - return -EACCES; - } - } - if (map_value_has_timer(map)) { - u32 t = map->timer_off; - - if (reg->smin_value + off < t + sizeof(struct bpf_timer) && - t < reg->umax_value + off + size) { - verbose(env, "bpf_timer cannot be accessed directly by load/store\n"); - return -EACCES; - } - } - if (map_value_has_kptrs(map)) { - struct bpf_map_value_off *tab = map->kptr_off_tab; - int i; - - for (i = 0; i < tab->nr_off; i++) { - u32 p = tab->off[i].offset; - - if (reg->smin_value + off < p + sizeof(u64) && - p < reg->umax_value + off + size) { + if (reg->smin_value + off < p + btf_field_type_size(field->type) && + p < reg->umax_value + off + size) { + switch (field->type) { + case BPF_KPTR_UNREF: + case BPF_KPTR_REF: if (src != ACCESS_DIRECT) { verbose(env, "kptr cannot be accessed indirectly by helper\n"); return -EACCES; @@ -3875,10 +4119,14 @@ static int check_map_access(struct bpf_verifier_env *env, u32 regno, return -EACCES; } break; + default: + verbose(env, "%s cannot be accessed directly by load/store\n", + btf_field_type_name(field->type)); + return -EACCES; } } } - return err; + return 0; } #define MAX_PACKET_OFF 0xffff @@ -4095,6 +4343,30 @@ static bool is_flow_key_reg(struct bpf_verifier_env *env, int regno) return reg->type == PTR_TO_FLOW_KEYS; } +static bool is_trusted_reg(const struct bpf_reg_state *reg) +{ + /* A referenced register is always trusted. */ + if (reg->ref_obj_id) + return true; + + /* If a register is not referenced, it is trusted if it has the + * MEM_ALLOC or PTR_TRUSTED type modifiers, and no others. Some of the + * other type modifiers may be safe, but we elect to take an opt-in + * approach here as some (e.g. PTR_UNTRUSTED and PTR_MAYBE_NULL) are + * not. + * + * Eventually, we should make PTR_TRUSTED the single source of truth + * for whether a register is trusted. + */ + return type_flag(reg->type) & BPF_REG_TRUSTED_MODIFIERS && + !bpf_type_has_unsafe_modifiers(reg->type); +} + +static bool is_rcu_reg(const struct bpf_reg_state *reg) +{ + return reg->type & MEM_RCU; +} + static int check_pkt_ptr_alignment(struct bpf_verifier_env *env, const struct bpf_reg_state *reg, int off, int size, bool strict) @@ -4511,6 +4783,18 @@ static int check_ptr_to_btf_access(struct bpf_verifier_env *env, u32 btf_id; int ret; + if (!env->allow_ptr_leaks) { + verbose(env, + "'struct %s' access is allowed only to CAP_PERFMON and CAP_SYS_ADMIN\n", + tname); + return -EPERM; + } + if (!env->prog->gpl_compatible && btf_is_kernel(reg->btf)) { + verbose(env, + "Cannot access kernel 'struct %s' from non-GPL compatible program\n", + tname); + return -EINVAL; + } if (off < 0) { verbose(env, "R%d is ptr_%s invalid negative access: off=%d\n", @@ -4541,17 +4825,28 @@ static int check_ptr_to_btf_access(struct bpf_verifier_env *env, return -EACCES; } - if (env->ops->btf_struct_access) { - ret = env->ops->btf_struct_access(&env->log, reg->btf, t, - off, size, atype, &btf_id, &flag); + if (env->ops->btf_struct_access && !type_is_alloc(reg->type)) { + if (!btf_is_kernel(reg->btf)) { + verbose(env, "verifier internal error: reg->btf must be kernel btf\n"); + return -EFAULT; + } + ret = env->ops->btf_struct_access(&env->log, reg, off, size, atype, &btf_id, &flag); } else { - if (atype != BPF_READ) { + /* Writes are permitted with default btf_struct_access for + * program allocated objects (which always have ref_obj_id > 0), + * but not for untrusted PTR_TO_BTF_ID | MEM_ALLOC. + */ + if (atype != BPF_READ && reg->type != (PTR_TO_BTF_ID | MEM_ALLOC)) { verbose(env, "only read is supported\n"); return -EACCES; } - ret = btf_struct_access(&env->log, reg->btf, t, off, size, - atype, &btf_id, &flag); + if (type_is_alloc(reg->type) && !reg->ref_obj_id) { + verbose(env, "verifier internal error: ref_obj_id for allocated object must be non-zero\n"); + return -EFAULT; + } + + ret = btf_struct_access(&env->log, reg, off, size, atype, &btf_id, &flag); } if (ret < 0) @@ -4563,6 +4858,30 @@ static int check_ptr_to_btf_access(struct bpf_verifier_env *env, if (type_flag(reg->type) & PTR_UNTRUSTED) flag |= PTR_UNTRUSTED; + /* By default any pointer obtained from walking a trusted pointer is + * no longer trusted except the rcu case below. + */ + flag &= ~PTR_TRUSTED; + + if (flag & MEM_RCU) { + /* Mark value register as MEM_RCU only if it is protected by + * bpf_rcu_read_lock() and the ptr reg is rcu or trusted. MEM_RCU + * itself can already indicate trustedness inside the rcu + * read lock region. Also mark rcu pointer as PTR_MAYBE_NULL since + * it could be null in some cases. + */ + if (!env->cur_state->active_rcu_lock || + !(is_trusted_reg(reg) || is_rcu_reg(reg))) + flag &= ~MEM_RCU; + else + flag |= PTR_MAYBE_NULL; + } else if (reg->type & MEM_RCU) { + /* ptr (reg) is marked as MEM_RCU, but the struct field is not tagged + * with __rcu. Mark the flag as PTR_UNTRUSTED conservatively. + */ + flag |= PTR_UNTRUSTED; + } + if (atype == BPF_READ && value_regno >= 0) mark_btf_ld_reg(env, regs, value_regno, ret, reg->btf, btf_id, flag); @@ -4577,6 +4896,7 @@ static int check_ptr_to_map_access(struct bpf_verifier_env *env, { struct bpf_reg_state *reg = regs + regno; struct bpf_map *map = reg->map_ptr; + struct bpf_reg_state map_reg; enum bpf_type_flag flag = 0; const struct btf_type *t; const char *tname; @@ -4597,9 +4917,9 @@ static int check_ptr_to_map_access(struct bpf_verifier_env *env, t = btf_type_by_id(btf_vmlinux, *map->ops->map_btf_id); tname = btf_name_by_offset(btf_vmlinux, t->name_off); - if (!env->allow_ptr_to_map_access) { + if (!env->allow_ptr_leaks) { verbose(env, - "%s access is allowed only to CAP_PERFMON and CAP_SYS_ADMIN\n", + "'struct %s' access is allowed only to CAP_PERFMON and CAP_SYS_ADMIN\n", tname); return -EPERM; } @@ -4615,7 +4935,10 @@ static int check_ptr_to_map_access(struct bpf_verifier_env *env, return -EACCES; } - ret = btf_struct_access(&env->log, btf_vmlinux, t, off, size, atype, &btf_id, &flag); + /* Simulate access to a PTR_TO_BTF_ID */ + memset(&map_reg, 0, sizeof(map_reg)); + mark_btf_ld_reg(env, &map_reg, 0, PTR_TO_BTF_ID, btf_vmlinux, *map->ops->map_btf_id, 0); + ret = btf_struct_access(&env->log, &map_reg, off, size, atype, &btf_id, &flag); if (ret < 0) return ret; @@ -4751,7 +5074,7 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn if (value_regno >= 0) mark_reg_unknown(env, regs, value_regno); } else if (reg->type == PTR_TO_MAP_VALUE) { - struct bpf_map_value_off_desc *kptr_off_desc = NULL; + struct btf_field *kptr_field = NULL; if (t == BPF_WRITE && value_regno >= 0 && is_pointer_value(env, value_regno)) { @@ -4765,11 +5088,10 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn if (err) return err; if (tnum_is_const(reg->var_off)) - kptr_off_desc = bpf_map_kptr_off_contains(reg->map_ptr, - off + reg->var_off.value); - if (kptr_off_desc) { - err = check_map_kptr_access(env, regno, value_regno, insn_idx, - kptr_off_desc); + kptr_field = btf_record_find(reg->map_ptr->record, + off + reg->var_off.value, BPF_KPTR); + if (kptr_field) { + err = check_map_kptr_access(env, regno, value_regno, insn_idx, kptr_field); } else if (t == BPF_READ && value_regno >= 0) { struct bpf_map *map = reg->map_ptr; @@ -5160,10 +5482,6 @@ static int check_stack_range_initialized( } if (is_spilled_reg(&state->stack[spi]) && - base_type(state->stack[spi].spilled_ptr.type) == PTR_TO_BTF_ID) - goto mark; - - if (is_spilled_reg(&state->stack[spi]) && (state->stack[spi].spilled_ptr.type == SCALAR_VALUE || env->allow_ptr_leaks)) { if (clobber) { @@ -5193,6 +5511,11 @@ mark: mark_reg_read(env, &state->stack[spi].spilled_ptr, state->stack[spi].spilled_ptr.parent, REG_LIVE_READ64); + /* We do not set REG_LIVE_WRITTEN for stack slot, as we can not + * be sure that whether stack slot is written to or not. Hence, + * we must still conservatively propagate reads upwards even if + * helper may write to the entire memory range. + */ } return update_stack_depth(env, state, min_off); } @@ -5374,8 +5697,8 @@ int check_mem_reg(struct bpf_verifier_env *env, struct bpf_reg_state *reg, return err; } -int check_kfunc_mem_size_reg(struct bpf_verifier_env *env, struct bpf_reg_state *reg, - u32 regno) +static int check_kfunc_mem_size_reg(struct bpf_verifier_env *env, struct bpf_reg_state *reg, + u32 regno) { struct bpf_reg_state *mem_reg = &cur_regs(env)[regno - 1]; bool may_be_null = type_may_be_null(mem_reg->type); @@ -5403,23 +5726,26 @@ int check_kfunc_mem_size_reg(struct bpf_verifier_env *env, struct bpf_reg_state } /* Implementation details: - * bpf_map_lookup returns PTR_TO_MAP_VALUE_OR_NULL + * bpf_map_lookup returns PTR_TO_MAP_VALUE_OR_NULL. + * bpf_obj_new returns PTR_TO_BTF_ID | MEM_ALLOC | PTR_MAYBE_NULL. * Two bpf_map_lookups (even with the same key) will have different reg->id. - * For traditional PTR_TO_MAP_VALUE the verifier clears reg->id after - * value_or_null->value transition, since the verifier only cares about - * the range of access to valid map value pointer and doesn't care about actual - * address of the map element. + * Two separate bpf_obj_new will also have different reg->id. + * For traditional PTR_TO_MAP_VALUE or PTR_TO_BTF_ID | MEM_ALLOC, the verifier + * clears reg->id after value_or_null->value transition, since the verifier only + * cares about the range of access to valid map value pointer and doesn't care + * about actual address of the map element. * For maps with 'struct bpf_spin_lock' inside map value the verifier keeps * reg->id > 0 after value_or_null->value transition. By doing so * two bpf_map_lookups will be considered two different pointers that - * point to different bpf_spin_locks. + * point to different bpf_spin_locks. Likewise for pointers to allocated objects + * returned from bpf_obj_new. * The verifier allows taking only one bpf_spin_lock at a time to avoid * dead-locks. * Since only one bpf_spin_lock is allowed the checks are simpler than * reg_is_refcounted() logic. The verifier needs to remember only * one spin_lock instead of array of acquired_refs. - * cur_state->active_spin_lock remembers which map value element got locked - * and clears it after bpf_spin_unlock. + * cur_state->active_lock remembers which map value element or allocated + * object got locked and clears it after bpf_spin_unlock. */ static int process_spin_lock(struct bpf_verifier_env *env, int regno, bool is_lock) @@ -5427,8 +5753,10 @@ static int process_spin_lock(struct bpf_verifier_env *env, int regno, struct bpf_reg_state *regs = cur_regs(env), *reg = ®s[regno]; struct bpf_verifier_state *cur = env->cur_state; bool is_const = tnum_is_const(reg->var_off); - struct bpf_map *map = reg->map_ptr; u64 val = reg->var_off.value; + struct bpf_map *map = NULL; + struct btf *btf = NULL; + struct btf_record *rec; if (!is_const) { verbose(env, @@ -5436,49 +5764,78 @@ static int process_spin_lock(struct bpf_verifier_env *env, int regno, regno); return -EINVAL; } - if (!map->btf) { - verbose(env, - "map '%s' has to have BTF in order to use bpf_spin_lock\n", - map->name); - return -EINVAL; - } - if (!map_value_has_spin_lock(map)) { - if (map->spin_lock_off == -E2BIG) - verbose(env, - "map '%s' has more than one 'struct bpf_spin_lock'\n", - map->name); - else if (map->spin_lock_off == -ENOENT) + if (reg->type == PTR_TO_MAP_VALUE) { + map = reg->map_ptr; + if (!map->btf) { verbose(env, - "map '%s' doesn't have 'struct bpf_spin_lock'\n", - map->name); - else - verbose(env, - "map '%s' is not a struct type or bpf_spin_lock is mangled\n", + "map '%s' has to have BTF in order to use bpf_spin_lock\n", map->name); + return -EINVAL; + } + } else { + btf = reg->btf; + } + + rec = reg_btf_record(reg); + if (!btf_record_has_field(rec, BPF_SPIN_LOCK)) { + verbose(env, "%s '%s' has no valid bpf_spin_lock\n", map ? "map" : "local", + map ? map->name : "kptr"); return -EINVAL; } - if (map->spin_lock_off != val + reg->off) { - verbose(env, "off %lld doesn't point to 'struct bpf_spin_lock'\n", - val + reg->off); + if (rec->spin_lock_off != val + reg->off) { + verbose(env, "off %lld doesn't point to 'struct bpf_spin_lock' that is at %d\n", + val + reg->off, rec->spin_lock_off); return -EINVAL; } if (is_lock) { - if (cur->active_spin_lock) { + if (cur->active_lock.ptr) { verbose(env, "Locking two bpf_spin_locks are not allowed\n"); return -EINVAL; } - cur->active_spin_lock = reg->id; + if (map) + cur->active_lock.ptr = map; + else + cur->active_lock.ptr = btf; + cur->active_lock.id = reg->id; } else { - if (!cur->active_spin_lock) { + struct bpf_func_state *fstate = cur_func(env); + void *ptr; + int i; + + if (map) + ptr = map; + else + ptr = btf; + + if (!cur->active_lock.ptr) { verbose(env, "bpf_spin_unlock without taking a lock\n"); return -EINVAL; } - if (cur->active_spin_lock != reg->id) { + if (cur->active_lock.ptr != ptr || + cur->active_lock.id != reg->id) { verbose(env, "bpf_spin_unlock of different lock\n"); return -EINVAL; } - cur->active_spin_lock = 0; + cur->active_lock.ptr = NULL; + cur->active_lock.id = 0; + + for (i = fstate->acquired_refs - 1; i >= 0; i--) { + int err; + + /* Complain on error because this reference state cannot + * be freed before this point, as bpf_spin_lock critical + * section does not allow functions that release the + * allocated object immediately. + */ + if (!fstate->refs[i].release_on_unlock) + continue; + err = release_reference(env, fstate->refs[i].id); + if (err) { + verbose(env, "failed to release release_on_unlock reference"); + return err; + } + } } return 0; } @@ -5502,24 +5859,13 @@ static int process_timer_func(struct bpf_verifier_env *env, int regno, map->name); return -EINVAL; } - if (!map_value_has_timer(map)) { - if (map->timer_off == -E2BIG) - verbose(env, - "map '%s' has more than one 'struct bpf_timer'\n", - map->name); - else if (map->timer_off == -ENOENT) - verbose(env, - "map '%s' doesn't have 'struct bpf_timer'\n", - map->name); - else - verbose(env, - "map '%s' is not a struct type or bpf_timer is mangled\n", - map->name); + if (!btf_record_has_field(map->record, BPF_TIMER)) { + verbose(env, "map '%s' has no valid bpf_timer\n", map->name); return -EINVAL; } - if (map->timer_off != val + reg->off) { + if (map->record->timer_off != val + reg->off) { verbose(env, "off %lld doesn't point to 'struct bpf_timer' that is at %d\n", - val + reg->off, map->timer_off); + val + reg->off, map->record->timer_off); return -EINVAL; } if (meta->map_ptr) { @@ -5535,10 +5881,9 @@ static int process_kptr_func(struct bpf_verifier_env *env, int regno, struct bpf_call_arg_meta *meta) { struct bpf_reg_state *regs = cur_regs(env), *reg = ®s[regno]; - struct bpf_map_value_off_desc *off_desc; struct bpf_map *map_ptr = reg->map_ptr; + struct btf_field *kptr_field; u32 kptr_off; - int ret; if (!tnum_is_const(reg->var_off)) { verbose(env, @@ -5551,30 +5896,136 @@ static int process_kptr_func(struct bpf_verifier_env *env, int regno, map_ptr->name); return -EINVAL; } - if (!map_value_has_kptrs(map_ptr)) { - ret = PTR_ERR_OR_ZERO(map_ptr->kptr_off_tab); - if (ret == -E2BIG) - verbose(env, "map '%s' has more than %d kptr\n", map_ptr->name, - BPF_MAP_VALUE_OFF_MAX); - else if (ret == -EEXIST) - verbose(env, "map '%s' has repeating kptr BTF tags\n", map_ptr->name); - else - verbose(env, "map '%s' has no valid kptr\n", map_ptr->name); + if (!btf_record_has_field(map_ptr->record, BPF_KPTR)) { + verbose(env, "map '%s' has no valid kptr\n", map_ptr->name); return -EINVAL; } meta->map_ptr = map_ptr; kptr_off = reg->off + reg->var_off.value; - off_desc = bpf_map_kptr_off_contains(map_ptr, kptr_off); - if (!off_desc) { + kptr_field = btf_record_find(map_ptr->record, kptr_off, BPF_KPTR); + if (!kptr_field) { verbose(env, "off=%d doesn't point to kptr\n", kptr_off); return -EACCES; } - if (off_desc->type != BPF_KPTR_REF) { + if (kptr_field->type != BPF_KPTR_REF) { verbose(env, "off=%d kptr isn't referenced kptr\n", kptr_off); return -EACCES; } - meta->kptr_off_desc = off_desc; + meta->kptr_field = kptr_field; + return 0; +} + +/* There are two register types representing a bpf_dynptr, one is PTR_TO_STACK + * which points to a stack slot, and the other is CONST_PTR_TO_DYNPTR. + * + * In both cases we deal with the first 8 bytes, but need to mark the next 8 + * bytes as STACK_DYNPTR in case of PTR_TO_STACK. In case of + * CONST_PTR_TO_DYNPTR, we are guaranteed to get the beginning of the object. + * + * Mutability of bpf_dynptr is at two levels, one is at the level of struct + * bpf_dynptr itself, i.e. whether the helper is receiving a pointer to struct + * bpf_dynptr or pointer to const struct bpf_dynptr. In the former case, it can + * mutate the view of the dynptr and also possibly destroy it. In the latter + * case, it cannot mutate the bpf_dynptr itself but it can still mutate the + * memory that dynptr points to. + * + * The verifier will keep track both levels of mutation (bpf_dynptr's in + * reg->type and the memory's in reg->dynptr.type), but there is no support for + * readonly dynptr view yet, hence only the first case is tracked and checked. + * + * This is consistent with how C applies the const modifier to a struct object, + * where the pointer itself inside bpf_dynptr becomes const but not what it + * points to. + * + * Helpers which do not mutate the bpf_dynptr set MEM_RDONLY in their argument + * type, and declare it as 'const struct bpf_dynptr *' in their prototype. + */ +int process_dynptr_func(struct bpf_verifier_env *env, int regno, + enum bpf_arg_type arg_type, struct bpf_call_arg_meta *meta) +{ + struct bpf_reg_state *regs = cur_regs(env), *reg = ®s[regno]; + + /* MEM_UNINIT and MEM_RDONLY are exclusive, when applied to an + * ARG_PTR_TO_DYNPTR (or ARG_PTR_TO_DYNPTR | DYNPTR_TYPE_*): + */ + if ((arg_type & (MEM_UNINIT | MEM_RDONLY)) == (MEM_UNINIT | MEM_RDONLY)) { + verbose(env, "verifier internal error: misconfigured dynptr helper type flags\n"); + return -EFAULT; + } + /* CONST_PTR_TO_DYNPTR already has fixed and var_off as 0 due to + * check_func_arg_reg_off's logic. We only need to check offset + * alignment for PTR_TO_STACK. + */ + if (reg->type == PTR_TO_STACK && (reg->off % BPF_REG_SIZE)) { + verbose(env, "cannot pass in dynptr at an offset=%d\n", reg->off); + return -EINVAL; + } + /* MEM_UNINIT - Points to memory that is an appropriate candidate for + * constructing a mutable bpf_dynptr object. + * + * Currently, this is only possible with PTR_TO_STACK + * pointing to a region of at least 16 bytes which doesn't + * contain an existing bpf_dynptr. + * + * MEM_RDONLY - Points to a initialized bpf_dynptr that will not be + * mutated or destroyed. However, the memory it points to + * may be mutated. + * + * None - Points to a initialized dynptr that can be mutated and + * destroyed, including mutation of the memory it points + * to. + */ + if (arg_type & MEM_UNINIT) { + if (!is_dynptr_reg_valid_uninit(env, reg)) { + verbose(env, "Dynptr has to be an uninitialized dynptr\n"); + return -EINVAL; + } + + /* We only support one dynptr being uninitialized at the moment, + * which is sufficient for the helper functions we have right now. + */ + if (meta->uninit_dynptr_regno) { + verbose(env, "verifier internal error: multiple uninitialized dynptr args\n"); + return -EFAULT; + } + + meta->uninit_dynptr_regno = regno; + } else /* MEM_RDONLY and None case from above */ { + /* For the reg->type == PTR_TO_STACK case, bpf_dynptr is never const */ + if (reg->type == CONST_PTR_TO_DYNPTR && !(arg_type & MEM_RDONLY)) { + verbose(env, "cannot pass pointer to const bpf_dynptr, the helper mutates it\n"); + return -EINVAL; + } + + if (!is_dynptr_reg_valid_init(env, reg)) { + verbose(env, + "Expected an initialized dynptr as arg #%d\n", + regno); + return -EINVAL; + } + + /* Fold modifiers (in this case, MEM_RDONLY) when checking expected type */ + if (!is_dynptr_type_expected(env, reg, arg_type & ~MEM_RDONLY)) { + const char *err_extra = ""; + + switch (arg_type & DYNPTR_TYPE_FLAG_MASK) { + case DYNPTR_TYPE_LOCAL: + err_extra = "local"; + break; + case DYNPTR_TYPE_RINGBUF: + err_extra = "ringbuf"; + break; + default: + err_extra = "<unknown>"; + break; + } + verbose(env, + "Expected a dynptr of type %s as arg #%d\n", + err_extra, regno); + return -EINVAL; + } + } return 0; } @@ -5639,16 +6090,6 @@ struct bpf_reg_types { u32 *btf_id; }; -static const struct bpf_reg_types map_key_value_types = { - .types = { - PTR_TO_STACK, - PTR_TO_PACKET, - PTR_TO_PACKET_META, - PTR_TO_MAP_KEY, - PTR_TO_MAP_VALUE, - }, -}; - static const struct bpf_reg_types sock_types = { .types = { PTR_TO_SOCK_COMMON, @@ -5666,6 +6107,7 @@ static const struct bpf_reg_types btf_id_sock_common_types = { PTR_TO_TCP_SOCK, PTR_TO_XDP_SOCK, PTR_TO_BTF_ID, + PTR_TO_BTF_ID | PTR_TRUSTED, }, .btf_id = &btf_sock_ids[BTF_SOCK_TYPE_SOCK_COMMON], }; @@ -5679,7 +6121,7 @@ static const struct bpf_reg_types mem_types = { PTR_TO_MAP_KEY, PTR_TO_MAP_VALUE, PTR_TO_MEM, - PTR_TO_MEM | MEM_ALLOC, + PTR_TO_MEM | MEM_RINGBUF, PTR_TO_BUF, }, }; @@ -5694,14 +6136,31 @@ static const struct bpf_reg_types int_ptr_types = { }, }; +static const struct bpf_reg_types spin_lock_types = { + .types = { + PTR_TO_MAP_VALUE, + PTR_TO_BTF_ID | MEM_ALLOC, + } +}; + static const struct bpf_reg_types fullsock_types = { .types = { PTR_TO_SOCKET } }; static const struct bpf_reg_types scalar_types = { .types = { SCALAR_VALUE } }; static const struct bpf_reg_types context_types = { .types = { PTR_TO_CTX } }; -static const struct bpf_reg_types alloc_mem_types = { .types = { PTR_TO_MEM | MEM_ALLOC } }; +static const struct bpf_reg_types ringbuf_mem_types = { .types = { PTR_TO_MEM | MEM_RINGBUF } }; static const struct bpf_reg_types const_map_ptr_types = { .types = { CONST_PTR_TO_MAP } }; -static const struct bpf_reg_types btf_ptr_types = { .types = { PTR_TO_BTF_ID } }; -static const struct bpf_reg_types spin_lock_types = { .types = { PTR_TO_MAP_VALUE } }; -static const struct bpf_reg_types percpu_btf_ptr_types = { .types = { PTR_TO_BTF_ID | MEM_PERCPU } }; +static const struct bpf_reg_types btf_ptr_types = { + .types = { + PTR_TO_BTF_ID, + PTR_TO_BTF_ID | PTR_TRUSTED, + PTR_TO_BTF_ID | MEM_RCU, + }, +}; +static const struct bpf_reg_types percpu_btf_ptr_types = { + .types = { + PTR_TO_BTF_ID | MEM_PERCPU, + PTR_TO_BTF_ID | MEM_PERCPU | PTR_TRUSTED, + } +}; static const struct bpf_reg_types func_ptr_types = { .types = { PTR_TO_FUNC } }; static const struct bpf_reg_types stack_ptr_types = { .types = { PTR_TO_STACK } }; static const struct bpf_reg_types const_str_ptr_types = { .types = { PTR_TO_MAP_VALUE } }; @@ -5710,13 +6169,13 @@ static const struct bpf_reg_types kptr_types = { .types = { PTR_TO_MAP_VALUE } } static const struct bpf_reg_types dynptr_types = { .types = { PTR_TO_STACK, - PTR_TO_DYNPTR | DYNPTR_TYPE_LOCAL, + CONST_PTR_TO_DYNPTR, } }; static const struct bpf_reg_types *compatible_reg_types[__BPF_ARG_TYPE_MAX] = { - [ARG_PTR_TO_MAP_KEY] = &map_key_value_types, - [ARG_PTR_TO_MAP_VALUE] = &map_key_value_types, + [ARG_PTR_TO_MAP_KEY] = &mem_types, + [ARG_PTR_TO_MAP_VALUE] = &mem_types, [ARG_CONST_SIZE] = &scalar_types, [ARG_CONST_SIZE_OR_ZERO] = &scalar_types, [ARG_CONST_ALLOC_SIZE_OR_ZERO] = &scalar_types, @@ -5730,7 +6189,7 @@ static const struct bpf_reg_types *compatible_reg_types[__BPF_ARG_TYPE_MAX] = { [ARG_PTR_TO_BTF_ID] = &btf_ptr_types, [ARG_PTR_TO_SPIN_LOCK] = &spin_lock_types, [ARG_PTR_TO_MEM] = &mem_types, - [ARG_PTR_TO_ALLOC_MEM] = &alloc_mem_types, + [ARG_PTR_TO_RINGBUF_MEM] = &ringbuf_mem_types, [ARG_PTR_TO_INT] = &int_ptr_types, [ARG_PTR_TO_LONG] = &int_ptr_types, [ARG_PTR_TO_PERCPU_BTF_ID] = &percpu_btf_ptr_types, @@ -5789,7 +6248,7 @@ static int check_reg_type(struct bpf_verifier_env *env, u32 regno, return -EACCES; found: - if (reg->type == PTR_TO_BTF_ID) { + if (reg->type == PTR_TO_BTF_ID || reg->type & PTR_TRUSTED) { /* For bpf_sk_release, it needs to match against first member * 'struct sock_common', hence make an exception for it. This * allows bpf_sk_release to work for multiple socket types. @@ -5806,7 +6265,7 @@ found: } if (meta->func_id == BPF_FUNC_kptr_xchg) { - if (map_kptr_match_type(env, meta->kptr_off_desc, reg, regno)) + if (map_kptr_match_type(env, meta->kptr_field, reg, regno)) return -EACCES; } else { if (arg_btf_id == BPF_PTR_POISON) { @@ -5825,6 +6284,11 @@ found: return -EACCES; } } + } else if (type_is_alloc(reg->type)) { + if (meta->func_id != BPF_FUNC_spin_lock && meta->func_id != BPF_FUNC_spin_unlock) { + verbose(env, "verifier internal error: unimplemented handling of MEM_ALLOC\n"); + return -EFAULT; + } } return 0; @@ -5834,64 +6298,80 @@ int check_func_arg_reg_off(struct bpf_verifier_env *env, const struct bpf_reg_state *reg, int regno, enum bpf_arg_type arg_type) { - enum bpf_reg_type type = reg->type; - bool fixed_off_ok = false; + u32 type = reg->type; - switch ((u32)type) { - /* Pointer types where reg offset is explicitly allowed: */ - case PTR_TO_STACK: - if (arg_type_is_dynptr(arg_type) && reg->off % BPF_REG_SIZE) { - verbose(env, "cannot pass in dynptr at an offset\n"); + /* When referenced register is passed to release function, its fixed + * offset must be 0. + * + * We will check arg_type_is_release reg has ref_obj_id when storing + * meta->release_regno. + */ + if (arg_type_is_release(arg_type)) { + /* ARG_PTR_TO_DYNPTR with OBJ_RELEASE is a bit special, as it + * may not directly point to the object being released, but to + * dynptr pointing to such object, which might be at some offset + * on the stack. In that case, we simply to fallback to the + * default handling. + */ + if (arg_type_is_dynptr(arg_type) && type == PTR_TO_STACK) + return 0; + /* Doing check_ptr_off_reg check for the offset will catch this + * because fixed_off_ok is false, but checking here allows us + * to give the user a better error message. + */ + if (reg->off) { + verbose(env, "R%d must have zero offset when passed to release func or trusted arg to kfunc\n", + regno); return -EINVAL; } - fallthrough; + return __check_ptr_off_reg(env, reg, regno, false); + } + + switch (type) { + /* Pointer types where both fixed and variable offset is explicitly allowed: */ + case PTR_TO_STACK: case PTR_TO_PACKET: case PTR_TO_PACKET_META: case PTR_TO_MAP_KEY: case PTR_TO_MAP_VALUE: case PTR_TO_MEM: case PTR_TO_MEM | MEM_RDONLY: - case PTR_TO_MEM | MEM_ALLOC: + case PTR_TO_MEM | MEM_RINGBUF: case PTR_TO_BUF: case PTR_TO_BUF | MEM_RDONLY: case SCALAR_VALUE: - /* Some of the argument types nevertheless require a - * zero register offset. - */ - if (base_type(arg_type) != ARG_PTR_TO_ALLOC_MEM) - return 0; - break; + return 0; /* All the rest must be rejected, except PTR_TO_BTF_ID which allows * fixed offset. */ case PTR_TO_BTF_ID: + case PTR_TO_BTF_ID | MEM_ALLOC: + case PTR_TO_BTF_ID | PTR_TRUSTED: + case PTR_TO_BTF_ID | MEM_RCU: + case PTR_TO_BTF_ID | MEM_ALLOC | PTR_TRUSTED: /* When referenced PTR_TO_BTF_ID is passed to release function, - * it's fixed offset must be 0. In the other cases, fixed offset - * can be non-zero. + * its fixed offset must be 0. In the other cases, fixed offset + * can be non-zero. This was already checked above. So pass + * fixed_off_ok as true to allow fixed offset for all other + * cases. var_off always must be 0 for PTR_TO_BTF_ID, hence we + * still need to do checks instead of returning. */ - if (arg_type_is_release(arg_type) && reg->off) { - verbose(env, "R%d must have zero offset when passed to release func\n", - regno); - return -EINVAL; - } - /* For arg is release pointer, fixed_off_ok must be false, but - * we already checked and rejected reg->off != 0 above, so set - * to true to allow fixed offset for all other cases. - */ - fixed_off_ok = true; - break; + return __check_ptr_off_reg(env, reg, regno, true); default: - break; + return __check_ptr_off_reg(env, reg, regno, false); } - return __check_ptr_off_reg(env, reg, regno, fixed_off_ok); } -static u32 stack_slot_get_id(struct bpf_verifier_env *env, struct bpf_reg_state *reg) +static u32 dynptr_ref_obj_id(struct bpf_verifier_env *env, struct bpf_reg_state *reg) { struct bpf_func_state *state = func(env, reg); - int spi = get_spi(reg->off); + int spi; - return state->stack[spi].spilled_ptr.id; + if (reg->type == CONST_PTR_TO_DYNPTR) + return reg->ref_obj_id; + + spi = get_spi(reg->off); + return state->stack[spi].spilled_ptr.ref_obj_id; } static int check_func_arg(struct bpf_verifier_env *env, u32 arg, @@ -5940,7 +6420,8 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg, goto skip_type_check; /* arg_btf_id and arg_size are in a union. */ - if (base_type(arg_type) == ARG_PTR_TO_BTF_ID) + if (base_type(arg_type) == ARG_PTR_TO_BTF_ID || + base_type(arg_type) == ARG_PTR_TO_SPIN_LOCK) arg_btf_id = fn->arg_btf_id[arg]; err = check_reg_type(env, regno, arg_type, arg_btf_id, meta); @@ -5955,11 +6436,22 @@ skip_type_check: if (arg_type_is_release(arg_type)) { if (arg_type_is_dynptr(arg_type)) { struct bpf_func_state *state = func(env, reg); - int spi = get_spi(reg->off); + int spi; - if (!is_spi_bounds_valid(state, spi, BPF_DYNPTR_NR_SLOTS) || - !state->stack[spi].spilled_ptr.id) { - verbose(env, "arg %d is an unacquired reference\n", regno); + /* Only dynptr created on stack can be released, thus + * the get_spi and stack state checks for spilled_ptr + * should only be done before process_dynptr_func for + * PTR_TO_STACK. + */ + if (reg->type == PTR_TO_STACK) { + spi = get_spi(reg->off); + if (!is_spi_bounds_valid(state, spi, BPF_DYNPTR_NR_SLOTS) || + !state->stack[spi].spilled_ptr.ref_obj_id) { + verbose(env, "arg %d is an unacquired reference\n", regno); + return -EINVAL; + } + } else { + verbose(env, "cannot release unowned const bpf_dynptr\n"); return -EINVAL; } } else if (!reg->ref_obj_id && !register_is_null(reg)) { @@ -6056,19 +6548,22 @@ skip_type_check: break; case ARG_PTR_TO_SPIN_LOCK: if (meta->func_id == BPF_FUNC_spin_lock) { - if (process_spin_lock(env, regno, true)) - return -EACCES; + err = process_spin_lock(env, regno, true); + if (err) + return err; } else if (meta->func_id == BPF_FUNC_spin_unlock) { - if (process_spin_lock(env, regno, false)) - return -EACCES; + err = process_spin_lock(env, regno, false); + if (err) + return err; } else { verbose(env, "verifier internal error\n"); return -EFAULT; } break; case ARG_PTR_TO_TIMER: - if (process_timer_func(env, regno, meta)) - return -EACCES; + err = process_timer_func(env, regno, meta); + if (err) + return err; break; case ARG_PTR_TO_FUNC: meta->subprogno = reg->subprogno; @@ -6091,52 +6586,9 @@ skip_type_check: err = check_mem_size_reg(env, reg, regno, true, meta); break; case ARG_PTR_TO_DYNPTR: - /* We only need to check for initialized / uninitialized helper - * dynptr args if the dynptr is not PTR_TO_DYNPTR, as the - * assumption is that if it is, that a helper function - * initialized the dynptr on behalf of the BPF program. - */ - if (base_type(reg->type) == PTR_TO_DYNPTR) - break; - if (arg_type & MEM_UNINIT) { - if (!is_dynptr_reg_valid_uninit(env, reg)) { - verbose(env, "Dynptr has to be an uninitialized dynptr\n"); - return -EINVAL; - } - - /* We only support one dynptr being uninitialized at the moment, - * which is sufficient for the helper functions we have right now. - */ - if (meta->uninit_dynptr_regno) { - verbose(env, "verifier internal error: multiple uninitialized dynptr args\n"); - return -EFAULT; - } - - meta->uninit_dynptr_regno = regno; - } else if (!is_dynptr_reg_valid_init(env, reg)) { - verbose(env, - "Expected an initialized dynptr as arg #%d\n", - arg + 1); - return -EINVAL; - } else if (!is_dynptr_type_expected(env, reg, arg_type)) { - const char *err_extra = ""; - - switch (arg_type & DYNPTR_TYPE_FLAG_MASK) { - case DYNPTR_TYPE_LOCAL: - err_extra = "local"; - break; - case DYNPTR_TYPE_RINGBUF: - err_extra = "ringbuf"; - break; - default: - err_extra = "<unknown>"; - break; - } - verbose(env, - "Expected a dynptr of type %s as arg #%d\n", - err_extra, arg + 1); - return -EINVAL; - } + err = process_dynptr_func(env, regno, arg_type, meta); + if (err) + return err; break; case ARG_CONST_ALLOC_SIZE_OR_ZERO: if (!tnum_is_const(reg->var_off)) { @@ -6203,8 +6655,9 @@ skip_type_check: break; } case ARG_PTR_TO_KPTR: - if (process_kptr_func(env, regno, meta)) - return -EACCES; + err = process_kptr_func(env, regno, meta); + if (err) + return err; break; } @@ -6365,6 +6818,11 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, func_id != BPF_FUNC_task_storage_delete) goto error; break; + case BPF_MAP_TYPE_CGRP_STORAGE: + if (func_id != BPF_FUNC_cgrp_storage_get && + func_id != BPF_FUNC_cgrp_storage_delete) + goto error; + break; case BPF_MAP_TYPE_BLOOM_FILTER: if (func_id != BPF_FUNC_map_peek_elem && func_id != BPF_FUNC_map_push_elem) @@ -6477,6 +6935,11 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, if (map->map_type != BPF_MAP_TYPE_TASK_STORAGE) goto error; break; + case BPF_FUNC_cgrp_storage_get: + case BPF_FUNC_cgrp_storage_delete: + if (map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) + goto error; + break; default: break; } @@ -6548,9 +7011,10 @@ static bool check_btf_id_ok(const struct bpf_func_proto *fn) int i; for (i = 0; i < ARRAY_SIZE(fn->arg_type); i++) { - if (base_type(fn->arg_type[i]) == ARG_PTR_TO_BTF_ID && !fn->arg_btf_id[i]) - return false; - + if (base_type(fn->arg_type[i]) == ARG_PTR_TO_BTF_ID) + return !!fn->arg_btf_id[i]; + if (base_type(fn->arg_type[i]) == ARG_PTR_TO_SPIN_LOCK) + return fn->arg_btf_id[i] == BPF_PTR_POISON; if (base_type(fn->arg_type[i]) != ARG_PTR_TO_BTF_ID && fn->arg_btf_id[i] && /* arg_btf_id and arg_size are in a union. */ (base_type(fn->arg_type[i]) != ARG_PTR_TO_MEM || @@ -6651,6 +7115,10 @@ typedef int (*set_callee_state_fn)(struct bpf_verifier_env *env, struct bpf_func_state *callee, int insn_idx); +static int set_callee_state(struct bpf_verifier_env *env, + struct bpf_func_state *caller, + struct bpf_func_state *callee, int insn_idx); + static int __check_func_call(struct bpf_verifier_env *env, struct bpf_insn *insn, int *insn_idx, int subprog, set_callee_state_fn set_callee_state_cb) @@ -6701,6 +7169,16 @@ static int __check_func_call(struct bpf_verifier_env *env, struct bpf_insn *insn } } + /* set_callee_state is used for direct subprog calls, but we are + * interested in validating only BPF helpers that can call subprogs as + * callbacks + */ + if (set_callee_state_cb != set_callee_state && !is_callback_calling_function(insn->imm)) { + verbose(env, "verifier bug: helper %s#%d is not marked as callback-calling\n", + func_id_name(insn->imm), insn->imm); + return -EFAULT; + } + if (insn->code == (BPF_JMP | BPF_CALL) && insn->src_reg == 0 && insn->imm == BPF_FUNC_timer_set_callback) { @@ -6947,11 +7425,10 @@ static int set_user_ringbuf_callback_state(struct bpf_verifier_env *env, { /* bpf_user_ringbuf_drain(struct bpf_map *map, void *callback_fn, void * callback_ctx, u64 flags); - * callback_fn(struct bpf_dynptr_t* dynptr, void *callback_ctx); + * callback_fn(const struct bpf_dynptr_t* dynptr, void *callback_ctx); */ __mark_reg_not_init(env, &callee->regs[BPF_REG_0]); - callee->regs[BPF_REG_1].type = PTR_TO_DYNPTR | DYNPTR_TYPE_LOCAL; - __mark_reg_known_zero(&callee->regs[BPF_REG_1]); + mark_dynptr_cb_reg(&callee->regs[BPF_REG_1], BPF_DYNPTR_TYPE_LOCAL); callee->regs[BPF_REG_2] = caller->regs[BPF_REG_3]; /* unused */ @@ -7283,6 +7760,11 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn return -EINVAL; } + if (!env->prog->aux->sleepable && fn->might_sleep) { + verbose(env, "helper call might sleep in a non-sleepable prog\n"); + return -EINVAL; + } + /* With LD_ABS/IND some JITs save/restore skb from r1. */ changes_data = bpf_helper_changes_pkt_data(fn->func); if (changes_data && fn->arg1_type != ARG_PTR_TO_CTX) { @@ -7301,6 +7783,17 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn return err; } + if (env->cur_state->active_rcu_lock) { + if (fn->might_sleep) { + verbose(env, "sleepable helper %s#%d in rcu_read_lock region\n", + func_id_name(func_id), func_id); + return -EINVAL; + } + + if (env->prog->aux->sleepable && is_storage_get_function(func_id)) + env->insn_aux_data[insn_idx].storage_get_func_atomic = true; + } + meta.func_id = func_id; /* check args */ for (i = 0; i < MAX_BPF_FUNC_REG_ARGS; i++) { @@ -7329,7 +7822,15 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn regs = cur_regs(env); + /* This can only be set for PTR_TO_STACK, as CONST_PTR_TO_DYNPTR cannot + * be reinitialized by any dynptr helper. Hence, mark_stack_slots_dynptr + * is safe to do directly. + */ if (meta.uninit_dynptr_regno) { + if (regs[meta.uninit_dynptr_regno].type == CONST_PTR_TO_DYNPTR) { + verbose(env, "verifier internal error: CONST_PTR_TO_DYNPTR cannot be initialized\n"); + return -EFAULT; + } /* we write BPF_DW bits (8 bytes) at a time */ for (i = 0; i < BPF_DYNPTR_SIZE; i += 8) { err = check_mem_access(env, insn_idx, meta.uninit_dynptr_regno, @@ -7347,15 +7848,24 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn if (meta.release_regno) { err = -EINVAL; - if (arg_type_is_dynptr(fn->arg_type[meta.release_regno - BPF_REG_1])) + /* This can only be set for PTR_TO_STACK, as CONST_PTR_TO_DYNPTR cannot + * be released by any dynptr helper. Hence, unmark_stack_slots_dynptr + * is safe to do directly. + */ + if (arg_type_is_dynptr(fn->arg_type[meta.release_regno - BPF_REG_1])) { + if (regs[meta.release_regno].type == CONST_PTR_TO_DYNPTR) { + verbose(env, "verifier internal error: CONST_PTR_TO_DYNPTR cannot be released\n"); + return -EFAULT; + } err = unmark_stack_slots_dynptr(env, ®s[meta.release_regno]); - else if (meta.ref_obj_id) + } else if (meta.ref_obj_id) { err = release_reference(env, meta.ref_obj_id); - /* meta.ref_obj_id can only be 0 if register that is meant to be - * released is NULL, which must be > R0. - */ - else if (register_is_null(®s[meta.release_regno])) + } else if (register_is_null(®s[meta.release_regno])) { + /* meta.ref_obj_id can only be 0 if register that is meant to be + * released is NULL, which must be > R0. + */ err = 0; + } if (err) { verbose(env, "func %s#%d reference has not been acquired before\n", func_id_name(func_id), func_id); @@ -7429,11 +7939,7 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn return -EFAULT; } - if (base_type(reg->type) != PTR_TO_DYNPTR) - /* Find the id of the dynptr we're - * tracking the reference of - */ - meta.ref_obj_id = stack_slot_get_id(env, reg); + meta.ref_obj_id = dynptr_ref_obj_id(env, reg); break; } } @@ -7488,7 +7994,7 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn regs[BPF_REG_0].map_uid = meta.map_uid; regs[BPF_REG_0].type = PTR_TO_MAP_VALUE | ret_flag; if (!type_may_be_null(ret_type) && - map_value_has_spin_lock(meta.map_ptr)) { + btf_record_has_field(meta.map_ptr->record, BPF_SPIN_LOCK)) { regs[BPF_REG_0].id = ++env->id_gen; } break; @@ -7504,7 +8010,7 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn mark_reg_known_zero(env, regs, BPF_REG_0); regs[BPF_REG_0].type = PTR_TO_TCP_SOCK | ret_flag; break; - case RET_PTR_TO_ALLOC_MEM: + case RET_PTR_TO_MEM: mark_reg_known_zero(env, regs, BPF_REG_0); regs[BPF_REG_0].type = PTR_TO_MEM | ret_flag; regs[BPF_REG_0].mem_size = meta.mem_size; @@ -7552,8 +8058,8 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn mark_reg_known_zero(env, regs, BPF_REG_0); regs[BPF_REG_0].type = PTR_TO_BTF_ID | ret_flag; if (func_id == BPF_FUNC_kptr_xchg) { - ret_btf = meta.kptr_off_desc->kptr.btf; - ret_btf_id = meta.kptr_off_desc->kptr.btf_id; + ret_btf = meta.kptr_field->kptr.btf; + ret_btf_id = meta.kptr_field->kptr.btf_id; } else { if (fn->ret_btf_id == BPF_PTR_POISON) { verbose(env, "verifier internal error:"); @@ -7667,19 +8173,926 @@ static void mark_btf_func_reg_size(struct bpf_verifier_env *env, u32 regno, } } +struct bpf_kfunc_call_arg_meta { + /* In parameters */ + struct btf *btf; + u32 func_id; + u32 kfunc_flags; + const struct btf_type *func_proto; + const char *func_name; + /* Out parameters */ + u32 ref_obj_id; + u8 release_regno; + bool r0_rdonly; + u32 ret_btf_id; + u64 r0_size; + struct { + u64 value; + bool found; + } arg_constant; + struct { + struct btf *btf; + u32 btf_id; + } arg_obj_drop; + struct { + struct btf_field *field; + } arg_list_head; +}; + +static bool is_kfunc_acquire(struct bpf_kfunc_call_arg_meta *meta) +{ + return meta->kfunc_flags & KF_ACQUIRE; +} + +static bool is_kfunc_ret_null(struct bpf_kfunc_call_arg_meta *meta) +{ + return meta->kfunc_flags & KF_RET_NULL; +} + +static bool is_kfunc_release(struct bpf_kfunc_call_arg_meta *meta) +{ + return meta->kfunc_flags & KF_RELEASE; +} + +static bool is_kfunc_trusted_args(struct bpf_kfunc_call_arg_meta *meta) +{ + return meta->kfunc_flags & KF_TRUSTED_ARGS; +} + +static bool is_kfunc_sleepable(struct bpf_kfunc_call_arg_meta *meta) +{ + return meta->kfunc_flags & KF_SLEEPABLE; +} + +static bool is_kfunc_destructive(struct bpf_kfunc_call_arg_meta *meta) +{ + return meta->kfunc_flags & KF_DESTRUCTIVE; +} + +static bool is_kfunc_rcu(struct bpf_kfunc_call_arg_meta *meta) +{ + return meta->kfunc_flags & KF_RCU; +} + +static bool is_kfunc_arg_kptr_get(struct bpf_kfunc_call_arg_meta *meta, int arg) +{ + return arg == 0 && (meta->kfunc_flags & KF_KPTR_GET); +} + +static bool __kfunc_param_match_suffix(const struct btf *btf, + const struct btf_param *arg, + const char *suffix) +{ + int suffix_len = strlen(suffix), len; + const char *param_name; + + /* In the future, this can be ported to use BTF tagging */ + param_name = btf_name_by_offset(btf, arg->name_off); + if (str_is_empty(param_name)) + return false; + len = strlen(param_name); + if (len < suffix_len) + return false; + param_name += len - suffix_len; + return !strncmp(param_name, suffix, suffix_len); +} + +static bool is_kfunc_arg_mem_size(const struct btf *btf, + const struct btf_param *arg, + const struct bpf_reg_state *reg) +{ + const struct btf_type *t; + + t = btf_type_skip_modifiers(btf, arg->type, NULL); + if (!btf_type_is_scalar(t) || reg->type != SCALAR_VALUE) + return false; + + return __kfunc_param_match_suffix(btf, arg, "__sz"); +} + +static bool is_kfunc_arg_constant(const struct btf *btf, const struct btf_param *arg) +{ + return __kfunc_param_match_suffix(btf, arg, "__k"); +} + +static bool is_kfunc_arg_ignore(const struct btf *btf, const struct btf_param *arg) +{ + return __kfunc_param_match_suffix(btf, arg, "__ign"); +} + +static bool is_kfunc_arg_alloc_obj(const struct btf *btf, const struct btf_param *arg) +{ + return __kfunc_param_match_suffix(btf, arg, "__alloc"); +} + +static bool is_kfunc_arg_scalar_with_name(const struct btf *btf, + const struct btf_param *arg, + const char *name) +{ + int len, target_len = strlen(name); + const char *param_name; + + param_name = btf_name_by_offset(btf, arg->name_off); + if (str_is_empty(param_name)) + return false; + len = strlen(param_name); + if (len != target_len) + return false; + if (strcmp(param_name, name)) + return false; + + return true; +} + +enum { + KF_ARG_DYNPTR_ID, + KF_ARG_LIST_HEAD_ID, + KF_ARG_LIST_NODE_ID, +}; + +BTF_ID_LIST(kf_arg_btf_ids) +BTF_ID(struct, bpf_dynptr_kern) +BTF_ID(struct, bpf_list_head) +BTF_ID(struct, bpf_list_node) + +static bool __is_kfunc_ptr_arg_type(const struct btf *btf, + const struct btf_param *arg, int type) +{ + const struct btf_type *t; + u32 res_id; + + t = btf_type_skip_modifiers(btf, arg->type, NULL); + if (!t) + return false; + if (!btf_type_is_ptr(t)) + return false; + t = btf_type_skip_modifiers(btf, t->type, &res_id); + if (!t) + return false; + return btf_types_are_same(btf, res_id, btf_vmlinux, kf_arg_btf_ids[type]); +} + +static bool is_kfunc_arg_dynptr(const struct btf *btf, const struct btf_param *arg) +{ + return __is_kfunc_ptr_arg_type(btf, arg, KF_ARG_DYNPTR_ID); +} + +static bool is_kfunc_arg_list_head(const struct btf *btf, const struct btf_param *arg) +{ + return __is_kfunc_ptr_arg_type(btf, arg, KF_ARG_LIST_HEAD_ID); +} + +static bool is_kfunc_arg_list_node(const struct btf *btf, const struct btf_param *arg) +{ + return __is_kfunc_ptr_arg_type(btf, arg, KF_ARG_LIST_NODE_ID); +} + +/* Returns true if struct is composed of scalars, 4 levels of nesting allowed */ +static bool __btf_type_is_scalar_struct(struct bpf_verifier_env *env, + const struct btf *btf, + const struct btf_type *t, int rec) +{ + const struct btf_type *member_type; + const struct btf_member *member; + u32 i; + + if (!btf_type_is_struct(t)) + return false; + + for_each_member(i, t, member) { + const struct btf_array *array; + + member_type = btf_type_skip_modifiers(btf, member->type, NULL); + if (btf_type_is_struct(member_type)) { + if (rec >= 3) { + verbose(env, "max struct nesting depth exceeded\n"); + return false; + } + if (!__btf_type_is_scalar_struct(env, btf, member_type, rec + 1)) + return false; + continue; + } + if (btf_type_is_array(member_type)) { + array = btf_array(member_type); + if (!array->nelems) + return false; + member_type = btf_type_skip_modifiers(btf, array->type, NULL); + if (!btf_type_is_scalar(member_type)) + return false; + continue; + } + if (!btf_type_is_scalar(member_type)) + return false; + } + return true; +} + + +static u32 *reg2btf_ids[__BPF_REG_TYPE_MAX] = { +#ifdef CONFIG_NET + [PTR_TO_SOCKET] = &btf_sock_ids[BTF_SOCK_TYPE_SOCK], + [PTR_TO_SOCK_COMMON] = &btf_sock_ids[BTF_SOCK_TYPE_SOCK_COMMON], + [PTR_TO_TCP_SOCK] = &btf_sock_ids[BTF_SOCK_TYPE_TCP], +#endif +}; + +enum kfunc_ptr_arg_type { + KF_ARG_PTR_TO_CTX, + KF_ARG_PTR_TO_ALLOC_BTF_ID, /* Allocated object */ + KF_ARG_PTR_TO_KPTR, /* PTR_TO_KPTR but type specific */ + KF_ARG_PTR_TO_DYNPTR, + KF_ARG_PTR_TO_LIST_HEAD, + KF_ARG_PTR_TO_LIST_NODE, + KF_ARG_PTR_TO_BTF_ID, /* Also covers reg2btf_ids conversions */ + KF_ARG_PTR_TO_MEM, + KF_ARG_PTR_TO_MEM_SIZE, /* Size derived from next argument, skip it */ +}; + +enum special_kfunc_type { + KF_bpf_obj_new_impl, + KF_bpf_obj_drop_impl, + KF_bpf_list_push_front, + KF_bpf_list_push_back, + KF_bpf_list_pop_front, + KF_bpf_list_pop_back, + KF_bpf_cast_to_kern_ctx, + KF_bpf_rdonly_cast, + KF_bpf_rcu_read_lock, + KF_bpf_rcu_read_unlock, +}; + +BTF_SET_START(special_kfunc_set) +BTF_ID(func, bpf_obj_new_impl) +BTF_ID(func, bpf_obj_drop_impl) +BTF_ID(func, bpf_list_push_front) +BTF_ID(func, bpf_list_push_back) +BTF_ID(func, bpf_list_pop_front) +BTF_ID(func, bpf_list_pop_back) +BTF_ID(func, bpf_cast_to_kern_ctx) +BTF_ID(func, bpf_rdonly_cast) +BTF_SET_END(special_kfunc_set) + +BTF_ID_LIST(special_kfunc_list) +BTF_ID(func, bpf_obj_new_impl) +BTF_ID(func, bpf_obj_drop_impl) +BTF_ID(func, bpf_list_push_front) +BTF_ID(func, bpf_list_push_back) +BTF_ID(func, bpf_list_pop_front) +BTF_ID(func, bpf_list_pop_back) +BTF_ID(func, bpf_cast_to_kern_ctx) +BTF_ID(func, bpf_rdonly_cast) +BTF_ID(func, bpf_rcu_read_lock) +BTF_ID(func, bpf_rcu_read_unlock) + +static bool is_kfunc_bpf_rcu_read_lock(struct bpf_kfunc_call_arg_meta *meta) +{ + return meta->func_id == special_kfunc_list[KF_bpf_rcu_read_lock]; +} + +static bool is_kfunc_bpf_rcu_read_unlock(struct bpf_kfunc_call_arg_meta *meta) +{ + return meta->func_id == special_kfunc_list[KF_bpf_rcu_read_unlock]; +} + +static enum kfunc_ptr_arg_type +get_kfunc_ptr_arg_type(struct bpf_verifier_env *env, + struct bpf_kfunc_call_arg_meta *meta, + const struct btf_type *t, const struct btf_type *ref_t, + const char *ref_tname, const struct btf_param *args, + int argno, int nargs) +{ + u32 regno = argno + 1; + struct bpf_reg_state *regs = cur_regs(env); + struct bpf_reg_state *reg = ®s[regno]; + bool arg_mem_size = false; + + if (meta->func_id == special_kfunc_list[KF_bpf_cast_to_kern_ctx]) + return KF_ARG_PTR_TO_CTX; + + /* In this function, we verify the kfunc's BTF as per the argument type, + * leaving the rest of the verification with respect to the register + * type to our caller. When a set of conditions hold in the BTF type of + * arguments, we resolve it to a known kfunc_ptr_arg_type. + */ + if (btf_get_prog_ctx_type(&env->log, meta->btf, t, resolve_prog_type(env->prog), argno)) + return KF_ARG_PTR_TO_CTX; + + if (is_kfunc_arg_alloc_obj(meta->btf, &args[argno])) + return KF_ARG_PTR_TO_ALLOC_BTF_ID; + + if (is_kfunc_arg_kptr_get(meta, argno)) { + if (!btf_type_is_ptr(ref_t)) { + verbose(env, "arg#0 BTF type must be a double pointer for kptr_get kfunc\n"); + return -EINVAL; + } + ref_t = btf_type_by_id(meta->btf, ref_t->type); + ref_tname = btf_name_by_offset(meta->btf, ref_t->name_off); + if (!btf_type_is_struct(ref_t)) { + verbose(env, "kernel function %s args#0 pointer type %s %s is not supported\n", + meta->func_name, btf_type_str(ref_t), ref_tname); + return -EINVAL; + } + return KF_ARG_PTR_TO_KPTR; + } + + if (is_kfunc_arg_dynptr(meta->btf, &args[argno])) + return KF_ARG_PTR_TO_DYNPTR; + + if (is_kfunc_arg_list_head(meta->btf, &args[argno])) + return KF_ARG_PTR_TO_LIST_HEAD; + + if (is_kfunc_arg_list_node(meta->btf, &args[argno])) + return KF_ARG_PTR_TO_LIST_NODE; + + if ((base_type(reg->type) == PTR_TO_BTF_ID || reg2btf_ids[base_type(reg->type)])) { + if (!btf_type_is_struct(ref_t)) { + verbose(env, "kernel function %s args#%d pointer type %s %s is not supported\n", + meta->func_name, argno, btf_type_str(ref_t), ref_tname); + return -EINVAL; + } + return KF_ARG_PTR_TO_BTF_ID; + } + + if (argno + 1 < nargs && is_kfunc_arg_mem_size(meta->btf, &args[argno + 1], ®s[regno + 1])) + arg_mem_size = true; + + /* This is the catch all argument type of register types supported by + * check_helper_mem_access. However, we only allow when argument type is + * pointer to scalar, or struct composed (recursively) of scalars. When + * arg_mem_size is true, the pointer can be void *. + */ + if (!btf_type_is_scalar(ref_t) && !__btf_type_is_scalar_struct(env, meta->btf, ref_t, 0) && + (arg_mem_size ? !btf_type_is_void(ref_t) : 1)) { + verbose(env, "arg#%d pointer type %s %s must point to %sscalar, or struct with scalar\n", + argno, btf_type_str(ref_t), ref_tname, arg_mem_size ? "void, " : ""); + return -EINVAL; + } + return arg_mem_size ? KF_ARG_PTR_TO_MEM_SIZE : KF_ARG_PTR_TO_MEM; +} + +static int process_kf_arg_ptr_to_btf_id(struct bpf_verifier_env *env, + struct bpf_reg_state *reg, + const struct btf_type *ref_t, + const char *ref_tname, u32 ref_id, + struct bpf_kfunc_call_arg_meta *meta, + int argno) +{ + const struct btf_type *reg_ref_t; + bool strict_type_match = false; + const struct btf *reg_btf; + const char *reg_ref_tname; + u32 reg_ref_id; + + if (base_type(reg->type) == PTR_TO_BTF_ID) { + reg_btf = reg->btf; + reg_ref_id = reg->btf_id; + } else { + reg_btf = btf_vmlinux; + reg_ref_id = *reg2btf_ids[base_type(reg->type)]; + } + + if (is_kfunc_trusted_args(meta) || (is_kfunc_release(meta) && reg->ref_obj_id)) + strict_type_match = true; + + reg_ref_t = btf_type_skip_modifiers(reg_btf, reg_ref_id, ®_ref_id); + reg_ref_tname = btf_name_by_offset(reg_btf, reg_ref_t->name_off); + if (!btf_struct_ids_match(&env->log, reg_btf, reg_ref_id, reg->off, meta->btf, ref_id, strict_type_match)) { + verbose(env, "kernel function %s args#%d expected pointer to %s %s but R%d has a pointer to %s %s\n", + meta->func_name, argno, btf_type_str(ref_t), ref_tname, argno + 1, + btf_type_str(reg_ref_t), reg_ref_tname); + return -EINVAL; + } + return 0; +} + +static int process_kf_arg_ptr_to_kptr(struct bpf_verifier_env *env, + struct bpf_reg_state *reg, + const struct btf_type *ref_t, + const char *ref_tname, + struct bpf_kfunc_call_arg_meta *meta, + int argno) +{ + struct btf_field *kptr_field; + + /* check_func_arg_reg_off allows var_off for + * PTR_TO_MAP_VALUE, but we need fixed offset to find + * off_desc. + */ + if (!tnum_is_const(reg->var_off)) { + verbose(env, "arg#0 must have constant offset\n"); + return -EINVAL; + } + + kptr_field = btf_record_find(reg->map_ptr->record, reg->off + reg->var_off.value, BPF_KPTR); + if (!kptr_field || kptr_field->type != BPF_KPTR_REF) { + verbose(env, "arg#0 no referenced kptr at map value offset=%llu\n", + reg->off + reg->var_off.value); + return -EINVAL; + } + + if (!btf_struct_ids_match(&env->log, meta->btf, ref_t->type, 0, kptr_field->kptr.btf, + kptr_field->kptr.btf_id, true)) { + verbose(env, "kernel function %s args#%d expected pointer to %s %s\n", + meta->func_name, argno, btf_type_str(ref_t), ref_tname); + return -EINVAL; + } + return 0; +} + +static int ref_set_release_on_unlock(struct bpf_verifier_env *env, u32 ref_obj_id) +{ + struct bpf_func_state *state = cur_func(env); + struct bpf_reg_state *reg; + int i; + + /* bpf_spin_lock only allows calling list_push and list_pop, no BPF + * subprogs, no global functions. This means that the references would + * not be released inside the critical section but they may be added to + * the reference state, and the acquired_refs are never copied out for a + * different frame as BPF to BPF calls don't work in bpf_spin_lock + * critical sections. + */ + if (!ref_obj_id) { + verbose(env, "verifier internal error: ref_obj_id is zero for release_on_unlock\n"); + return -EFAULT; + } + for (i = 0; i < state->acquired_refs; i++) { + if (state->refs[i].id == ref_obj_id) { + if (state->refs[i].release_on_unlock) { + verbose(env, "verifier internal error: expected false release_on_unlock"); + return -EFAULT; + } + state->refs[i].release_on_unlock = true; + /* Now mark everyone sharing same ref_obj_id as untrusted */ + bpf_for_each_reg_in_vstate(env->cur_state, state, reg, ({ + if (reg->ref_obj_id == ref_obj_id) + reg->type |= PTR_UNTRUSTED; + })); + return 0; + } + } + verbose(env, "verifier internal error: ref state missing for ref_obj_id\n"); + return -EFAULT; +} + +/* Implementation details: + * + * Each register points to some region of memory, which we define as an + * allocation. Each allocation may embed a bpf_spin_lock which protects any + * special BPF objects (bpf_list_head, bpf_rb_root, etc.) part of the same + * allocation. The lock and the data it protects are colocated in the same + * memory region. + * + * Hence, everytime a register holds a pointer value pointing to such + * allocation, the verifier preserves a unique reg->id for it. + * + * The verifier remembers the lock 'ptr' and the lock 'id' whenever + * bpf_spin_lock is called. + * + * To enable this, lock state in the verifier captures two values: + * active_lock.ptr = Register's type specific pointer + * active_lock.id = A unique ID for each register pointer value + * + * Currently, PTR_TO_MAP_VALUE and PTR_TO_BTF_ID | MEM_ALLOC are the two + * supported register types. + * + * The active_lock.ptr in case of map values is the reg->map_ptr, and in case of + * allocated objects is the reg->btf pointer. + * + * The active_lock.id is non-unique for maps supporting direct_value_addr, as we + * can establish the provenance of the map value statically for each distinct + * lookup into such maps. They always contain a single map value hence unique + * IDs for each pseudo load pessimizes the algorithm and rejects valid programs. + * + * So, in case of global variables, they use array maps with max_entries = 1, + * hence their active_lock.ptr becomes map_ptr and id = 0 (since they all point + * into the same map value as max_entries is 1, as described above). + * + * In case of inner map lookups, the inner map pointer has same map_ptr as the + * outer map pointer (in verifier context), but each lookup into an inner map + * assigns a fresh reg->id to the lookup, so while lookups into distinct inner + * maps from the same outer map share the same map_ptr as active_lock.ptr, they + * will get different reg->id assigned to each lookup, hence different + * active_lock.id. + * + * In case of allocated objects, active_lock.ptr is the reg->btf, and the + * reg->id is a unique ID preserved after the NULL pointer check on the pointer + * returned from bpf_obj_new. Each allocation receives a new reg->id. + */ +static int check_reg_allocation_locked(struct bpf_verifier_env *env, struct bpf_reg_state *reg) +{ + void *ptr; + u32 id; + + switch ((int)reg->type) { + case PTR_TO_MAP_VALUE: + ptr = reg->map_ptr; + break; + case PTR_TO_BTF_ID | MEM_ALLOC: + case PTR_TO_BTF_ID | MEM_ALLOC | PTR_TRUSTED: + ptr = reg->btf; + break; + default: + verbose(env, "verifier internal error: unknown reg type for lock check\n"); + return -EFAULT; + } + id = reg->id; + + if (!env->cur_state->active_lock.ptr) + return -EINVAL; + if (env->cur_state->active_lock.ptr != ptr || + env->cur_state->active_lock.id != id) { + verbose(env, "held lock and object are not in the same allocation\n"); + return -EINVAL; + } + return 0; +} + +static bool is_bpf_list_api_kfunc(u32 btf_id) +{ + return btf_id == special_kfunc_list[KF_bpf_list_push_front] || + btf_id == special_kfunc_list[KF_bpf_list_push_back] || + btf_id == special_kfunc_list[KF_bpf_list_pop_front] || + btf_id == special_kfunc_list[KF_bpf_list_pop_back]; +} + +static int process_kf_arg_ptr_to_list_head(struct bpf_verifier_env *env, + struct bpf_reg_state *reg, u32 regno, + struct bpf_kfunc_call_arg_meta *meta) +{ + struct btf_field *field; + struct btf_record *rec; + u32 list_head_off; + + if (meta->btf != btf_vmlinux || !is_bpf_list_api_kfunc(meta->func_id)) { + verbose(env, "verifier internal error: bpf_list_head argument for unknown kfunc\n"); + return -EFAULT; + } + + if (!tnum_is_const(reg->var_off)) { + verbose(env, + "R%d doesn't have constant offset. bpf_list_head has to be at the constant offset\n", + regno); + return -EINVAL; + } + + rec = reg_btf_record(reg); + list_head_off = reg->off + reg->var_off.value; + field = btf_record_find(rec, list_head_off, BPF_LIST_HEAD); + if (!field) { + verbose(env, "bpf_list_head not found at offset=%u\n", list_head_off); + return -EINVAL; + } + + /* All functions require bpf_list_head to be protected using a bpf_spin_lock */ + if (check_reg_allocation_locked(env, reg)) { + verbose(env, "bpf_spin_lock at off=%d must be held for bpf_list_head\n", + rec->spin_lock_off); + return -EINVAL; + } + + if (meta->arg_list_head.field) { + verbose(env, "verifier internal error: repeating bpf_list_head arg\n"); + return -EFAULT; + } + meta->arg_list_head.field = field; + return 0; +} + +static int process_kf_arg_ptr_to_list_node(struct bpf_verifier_env *env, + struct bpf_reg_state *reg, u32 regno, + struct bpf_kfunc_call_arg_meta *meta) +{ + const struct btf_type *et, *t; + struct btf_field *field; + struct btf_record *rec; + u32 list_node_off; + + if (meta->btf != btf_vmlinux || + (meta->func_id != special_kfunc_list[KF_bpf_list_push_front] && + meta->func_id != special_kfunc_list[KF_bpf_list_push_back])) { + verbose(env, "verifier internal error: bpf_list_node argument for unknown kfunc\n"); + return -EFAULT; + } + + if (!tnum_is_const(reg->var_off)) { + verbose(env, + "R%d doesn't have constant offset. bpf_list_node has to be at the constant offset\n", + regno); + return -EINVAL; + } + + rec = reg_btf_record(reg); + list_node_off = reg->off + reg->var_off.value; + field = btf_record_find(rec, list_node_off, BPF_LIST_NODE); + if (!field || field->offset != list_node_off) { + verbose(env, "bpf_list_node not found at offset=%u\n", list_node_off); + return -EINVAL; + } + + field = meta->arg_list_head.field; + + et = btf_type_by_id(field->list_head.btf, field->list_head.value_btf_id); + t = btf_type_by_id(reg->btf, reg->btf_id); + if (!btf_struct_ids_match(&env->log, reg->btf, reg->btf_id, 0, field->list_head.btf, + field->list_head.value_btf_id, true)) { + verbose(env, "operation on bpf_list_head expects arg#1 bpf_list_node at offset=%d " + "in struct %s, but arg is at offset=%d in struct %s\n", + field->list_head.node_offset, btf_name_by_offset(field->list_head.btf, et->name_off), + list_node_off, btf_name_by_offset(reg->btf, t->name_off)); + return -EINVAL; + } + + if (list_node_off != field->list_head.node_offset) { + verbose(env, "arg#1 offset=%d, but expected bpf_list_node at offset=%d in struct %s\n", + list_node_off, field->list_head.node_offset, + btf_name_by_offset(field->list_head.btf, et->name_off)); + return -EINVAL; + } + /* Set arg#1 for expiration after unlock */ + return ref_set_release_on_unlock(env, reg->ref_obj_id); +} + +static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_kfunc_call_arg_meta *meta) +{ + const char *func_name = meta->func_name, *ref_tname; + const struct btf *btf = meta->btf; + const struct btf_param *args; + u32 i, nargs; + int ret; + + args = (const struct btf_param *)(meta->func_proto + 1); + nargs = btf_type_vlen(meta->func_proto); + if (nargs > MAX_BPF_FUNC_REG_ARGS) { + verbose(env, "Function %s has %d > %d args\n", func_name, nargs, + MAX_BPF_FUNC_REG_ARGS); + return -EINVAL; + } + + /* Check that BTF function arguments match actual types that the + * verifier sees. + */ + for (i = 0; i < nargs; i++) { + struct bpf_reg_state *regs = cur_regs(env), *reg = ®s[i + 1]; + const struct btf_type *t, *ref_t, *resolve_ret; + enum bpf_arg_type arg_type = ARG_DONTCARE; + u32 regno = i + 1, ref_id, type_size; + bool is_ret_buf_sz = false; + int kf_arg_type; + + t = btf_type_skip_modifiers(btf, args[i].type, NULL); + + if (is_kfunc_arg_ignore(btf, &args[i])) + continue; + + if (btf_type_is_scalar(t)) { + if (reg->type != SCALAR_VALUE) { + verbose(env, "R%d is not a scalar\n", regno); + return -EINVAL; + } + + if (is_kfunc_arg_constant(meta->btf, &args[i])) { + if (meta->arg_constant.found) { + verbose(env, "verifier internal error: only one constant argument permitted\n"); + return -EFAULT; + } + if (!tnum_is_const(reg->var_off)) { + verbose(env, "R%d must be a known constant\n", regno); + return -EINVAL; + } + ret = mark_chain_precision(env, regno); + if (ret < 0) + return ret; + meta->arg_constant.found = true; + meta->arg_constant.value = reg->var_off.value; + } else if (is_kfunc_arg_scalar_with_name(btf, &args[i], "rdonly_buf_size")) { + meta->r0_rdonly = true; + is_ret_buf_sz = true; + } else if (is_kfunc_arg_scalar_with_name(btf, &args[i], "rdwr_buf_size")) { + is_ret_buf_sz = true; + } + + if (is_ret_buf_sz) { + if (meta->r0_size) { + verbose(env, "2 or more rdonly/rdwr_buf_size parameters for kfunc"); + return -EINVAL; + } + + if (!tnum_is_const(reg->var_off)) { + verbose(env, "R%d is not a const\n", regno); + return -EINVAL; + } + + meta->r0_size = reg->var_off.value; + ret = mark_chain_precision(env, regno); + if (ret) + return ret; + } + continue; + } + + if (!btf_type_is_ptr(t)) { + verbose(env, "Unrecognized arg#%d type %s\n", i, btf_type_str(t)); + return -EINVAL; + } + + if (reg->ref_obj_id) { + if (is_kfunc_release(meta) && meta->ref_obj_id) { + verbose(env, "verifier internal error: more than one arg with ref_obj_id R%d %u %u\n", + regno, reg->ref_obj_id, + meta->ref_obj_id); + return -EFAULT; + } + meta->ref_obj_id = reg->ref_obj_id; + if (is_kfunc_release(meta)) + meta->release_regno = regno; + } + + ref_t = btf_type_skip_modifiers(btf, t->type, &ref_id); + ref_tname = btf_name_by_offset(btf, ref_t->name_off); + + kf_arg_type = get_kfunc_ptr_arg_type(env, meta, t, ref_t, ref_tname, args, i, nargs); + if (kf_arg_type < 0) + return kf_arg_type; + + switch (kf_arg_type) { + case KF_ARG_PTR_TO_ALLOC_BTF_ID: + case KF_ARG_PTR_TO_BTF_ID: + if (!is_kfunc_trusted_args(meta) && !is_kfunc_rcu(meta)) + break; + + if (!is_trusted_reg(reg)) { + if (!is_kfunc_rcu(meta)) { + verbose(env, "R%d must be referenced or trusted\n", regno); + return -EINVAL; + } + if (!is_rcu_reg(reg)) { + verbose(env, "R%d must be a rcu pointer\n", regno); + return -EINVAL; + } + } + + fallthrough; + case KF_ARG_PTR_TO_CTX: + /* Trusted arguments have the same offset checks as release arguments */ + arg_type |= OBJ_RELEASE; + break; + case KF_ARG_PTR_TO_KPTR: + case KF_ARG_PTR_TO_DYNPTR: + case KF_ARG_PTR_TO_LIST_HEAD: + case KF_ARG_PTR_TO_LIST_NODE: + case KF_ARG_PTR_TO_MEM: + case KF_ARG_PTR_TO_MEM_SIZE: + /* Trusted by default */ + break; + default: + WARN_ON_ONCE(1); + return -EFAULT; + } + + if (is_kfunc_release(meta) && reg->ref_obj_id) + arg_type |= OBJ_RELEASE; + ret = check_func_arg_reg_off(env, reg, regno, arg_type); + if (ret < 0) + return ret; + + switch (kf_arg_type) { + case KF_ARG_PTR_TO_CTX: + if (reg->type != PTR_TO_CTX) { + verbose(env, "arg#%d expected pointer to ctx, but got %s\n", i, btf_type_str(t)); + return -EINVAL; + } + + if (meta->func_id == special_kfunc_list[KF_bpf_cast_to_kern_ctx]) { + ret = get_kern_ctx_btf_id(&env->log, resolve_prog_type(env->prog)); + if (ret < 0) + return -EINVAL; + meta->ret_btf_id = ret; + } + break; + case KF_ARG_PTR_TO_ALLOC_BTF_ID: + if (reg->type != (PTR_TO_BTF_ID | MEM_ALLOC)) { + verbose(env, "arg#%d expected pointer to allocated object\n", i); + return -EINVAL; + } + if (!reg->ref_obj_id) { + verbose(env, "allocated object must be referenced\n"); + return -EINVAL; + } + if (meta->btf == btf_vmlinux && + meta->func_id == special_kfunc_list[KF_bpf_obj_drop_impl]) { + meta->arg_obj_drop.btf = reg->btf; + meta->arg_obj_drop.btf_id = reg->btf_id; + } + break; + case KF_ARG_PTR_TO_KPTR: + if (reg->type != PTR_TO_MAP_VALUE) { + verbose(env, "arg#0 expected pointer to map value\n"); + return -EINVAL; + } + ret = process_kf_arg_ptr_to_kptr(env, reg, ref_t, ref_tname, meta, i); + if (ret < 0) + return ret; + break; + case KF_ARG_PTR_TO_DYNPTR: + if (reg->type != PTR_TO_STACK && + reg->type != CONST_PTR_TO_DYNPTR) { + verbose(env, "arg#%d expected pointer to stack or dynptr_ptr\n", i); + return -EINVAL; + } + + ret = process_dynptr_func(env, regno, ARG_PTR_TO_DYNPTR | MEM_RDONLY, NULL); + if (ret < 0) + return ret; + break; + case KF_ARG_PTR_TO_LIST_HEAD: + if (reg->type != PTR_TO_MAP_VALUE && + reg->type != (PTR_TO_BTF_ID | MEM_ALLOC)) { + verbose(env, "arg#%d expected pointer to map value or allocated object\n", i); + return -EINVAL; + } + if (reg->type == (PTR_TO_BTF_ID | MEM_ALLOC) && !reg->ref_obj_id) { + verbose(env, "allocated object must be referenced\n"); + return -EINVAL; + } + ret = process_kf_arg_ptr_to_list_head(env, reg, regno, meta); + if (ret < 0) + return ret; + break; + case KF_ARG_PTR_TO_LIST_NODE: + if (reg->type != (PTR_TO_BTF_ID | MEM_ALLOC)) { + verbose(env, "arg#%d expected pointer to allocated object\n", i); + return -EINVAL; + } + if (!reg->ref_obj_id) { + verbose(env, "allocated object must be referenced\n"); + return -EINVAL; + } + ret = process_kf_arg_ptr_to_list_node(env, reg, regno, meta); + if (ret < 0) + return ret; + break; + case KF_ARG_PTR_TO_BTF_ID: + /* Only base_type is checked, further checks are done here */ + if ((base_type(reg->type) != PTR_TO_BTF_ID || + (bpf_type_has_unsafe_modifiers(reg->type) && !is_rcu_reg(reg))) && + !reg2btf_ids[base_type(reg->type)]) { + verbose(env, "arg#%d is %s ", i, reg_type_str(env, reg->type)); + verbose(env, "expected %s or socket\n", + reg_type_str(env, base_type(reg->type) | + (type_flag(reg->type) & BPF_REG_TRUSTED_MODIFIERS))); + return -EINVAL; + } + ret = process_kf_arg_ptr_to_btf_id(env, reg, ref_t, ref_tname, ref_id, meta, i); + if (ret < 0) + return ret; + break; + case KF_ARG_PTR_TO_MEM: + resolve_ret = btf_resolve_size(btf, ref_t, &type_size); + if (IS_ERR(resolve_ret)) { + verbose(env, "arg#%d reference type('%s %s') size cannot be determined: %ld\n", + i, btf_type_str(ref_t), ref_tname, PTR_ERR(resolve_ret)); + return -EINVAL; + } + ret = check_mem_reg(env, reg, regno, type_size); + if (ret < 0) + return ret; + break; + case KF_ARG_PTR_TO_MEM_SIZE: + ret = check_kfunc_mem_size_reg(env, ®s[regno + 1], regno + 1); + if (ret < 0) { + verbose(env, "arg#%d arg#%d memory, len pair leads to invalid memory access\n", i, i + 1); + return ret; + } + /* Skip next '__sz' argument */ + i++; + break; + } + } + + if (is_kfunc_release(meta) && !meta->release_regno) { + verbose(env, "release kernel function %s expects refcounted PTR_TO_BTF_ID\n", + func_name); + return -EINVAL; + } + + return 0; +} + static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, int *insn_idx_p) { const struct btf_type *t, *func, *func_proto, *ptr_type; struct bpf_reg_state *regs = cur_regs(env); - struct bpf_kfunc_arg_meta meta = { 0 }; const char *func_name, *ptr_type_name; + bool sleepable, rcu_lock, rcu_unlock; + struct bpf_kfunc_call_arg_meta meta; u32 i, nargs, func_id, ptr_type_id; int err, insn_idx = *insn_idx_p; const struct btf_param *args; + const struct btf_type *ret_t; struct btf *desc_btf; u32 *kfunc_flags; - bool acq; /* skip for now, but return error when we find this in fixup_kfunc_call */ if (!insn->imm) @@ -7700,24 +9113,68 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, func_name); return -EACCES; } - if (*kfunc_flags & KF_DESTRUCTIVE && !capable(CAP_SYS_BOOT)) { - verbose(env, "destructive kfunc calls require CAP_SYS_BOOT capabilities\n"); + + /* Prepare kfunc call metadata */ + memset(&meta, 0, sizeof(meta)); + meta.btf = desc_btf; + meta.func_id = func_id; + meta.kfunc_flags = *kfunc_flags; + meta.func_proto = func_proto; + meta.func_name = func_name; + + if (is_kfunc_destructive(&meta) && !capable(CAP_SYS_BOOT)) { + verbose(env, "destructive kfunc calls require CAP_SYS_BOOT capability\n"); + return -EACCES; + } + + sleepable = is_kfunc_sleepable(&meta); + if (sleepable && !env->prog->aux->sleepable) { + verbose(env, "program must be sleepable to call sleepable kfunc %s\n", func_name); return -EACCES; } - acq = *kfunc_flags & KF_ACQUIRE; + rcu_lock = is_kfunc_bpf_rcu_read_lock(&meta); + rcu_unlock = is_kfunc_bpf_rcu_read_unlock(&meta); + if ((rcu_lock || rcu_unlock) && !env->rcu_tag_supported) { + verbose(env, "no vmlinux btf rcu tag support for kfunc %s\n", func_name); + return -EACCES; + } - meta.flags = *kfunc_flags; + if (env->cur_state->active_rcu_lock) { + struct bpf_func_state *state; + struct bpf_reg_state *reg; + + if (rcu_lock) { + verbose(env, "nested rcu read lock (kernel function %s)\n", func_name); + return -EINVAL; + } else if (rcu_unlock) { + bpf_for_each_reg_in_vstate(env->cur_state, state, reg, ({ + if (reg->type & MEM_RCU) { + reg->type &= ~(MEM_RCU | PTR_MAYBE_NULL); + reg->type |= PTR_UNTRUSTED; + } + })); + env->cur_state->active_rcu_lock = false; + } else if (sleepable) { + verbose(env, "kernel func %s is sleepable within rcu_read_lock region\n", func_name); + return -EACCES; + } + } else if (rcu_lock) { + env->cur_state->active_rcu_lock = true; + } else if (rcu_unlock) { + verbose(env, "unmatched rcu read unlock (kernel function %s)\n", func_name); + return -EINVAL; + } /* Check the arguments */ - err = btf_check_kfunc_arg_match(env, desc_btf, func_id, regs, &meta); + err = check_kfunc_args(env, &meta); if (err < 0) return err; /* In case of release function, we get register number of refcounted - * PTR_TO_BTF_ID back from btf_check_kfunc_arg_match, do the release now + * PTR_TO_BTF_ID in bpf_kfunc_arg_meta, do the release now. */ - if (err) { - err = release_reference(env, regs[err].ref_obj_id); + if (meta.release_regno) { + err = release_reference(env, regs[meta.release_regno].ref_obj_id); if (err) { verbose(env, "kfunc %s#%d reference has not been acquired before\n", func_name, func_id); @@ -7731,18 +9188,92 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, /* Check return type */ t = btf_type_skip_modifiers(desc_btf, func_proto->type, NULL); - if (acq && !btf_type_is_struct_ptr(desc_btf, t)) { - verbose(env, "acquire kernel function does not return PTR_TO_BTF_ID\n"); - return -EINVAL; + if (is_kfunc_acquire(&meta) && !btf_type_is_struct_ptr(meta.btf, t)) { + /* Only exception is bpf_obj_new_impl */ + if (meta.btf != btf_vmlinux || meta.func_id != special_kfunc_list[KF_bpf_obj_new_impl]) { + verbose(env, "acquire kernel function does not return PTR_TO_BTF_ID\n"); + return -EINVAL; + } } if (btf_type_is_scalar(t)) { mark_reg_unknown(env, regs, BPF_REG_0); mark_btf_func_reg_size(env, BPF_REG_0, t->size); } else if (btf_type_is_ptr(t)) { - ptr_type = btf_type_skip_modifiers(desc_btf, t->type, - &ptr_type_id); - if (!btf_type_is_struct(ptr_type)) { + ptr_type = btf_type_skip_modifiers(desc_btf, t->type, &ptr_type_id); + + if (meta.btf == btf_vmlinux && btf_id_set_contains(&special_kfunc_set, meta.func_id)) { + if (meta.func_id == special_kfunc_list[KF_bpf_obj_new_impl]) { + struct btf *ret_btf; + u32 ret_btf_id; + + if (unlikely(!bpf_global_ma_set)) + return -ENOMEM; + + if (((u64)(u32)meta.arg_constant.value) != meta.arg_constant.value) { + verbose(env, "local type ID argument must be in range [0, U32_MAX]\n"); + return -EINVAL; + } + + ret_btf = env->prog->aux->btf; + ret_btf_id = meta.arg_constant.value; + + /* This may be NULL due to user not supplying a BTF */ + if (!ret_btf) { + verbose(env, "bpf_obj_new requires prog BTF\n"); + return -EINVAL; + } + + ret_t = btf_type_by_id(ret_btf, ret_btf_id); + if (!ret_t || !__btf_type_is_struct(ret_t)) { + verbose(env, "bpf_obj_new type ID argument must be of a struct\n"); + return -EINVAL; + } + + mark_reg_known_zero(env, regs, BPF_REG_0); + regs[BPF_REG_0].type = PTR_TO_BTF_ID | MEM_ALLOC; + regs[BPF_REG_0].btf = ret_btf; + regs[BPF_REG_0].btf_id = ret_btf_id; + + env->insn_aux_data[insn_idx].obj_new_size = ret_t->size; + env->insn_aux_data[insn_idx].kptr_struct_meta = + btf_find_struct_meta(ret_btf, ret_btf_id); + } else if (meta.func_id == special_kfunc_list[KF_bpf_obj_drop_impl]) { + env->insn_aux_data[insn_idx].kptr_struct_meta = + btf_find_struct_meta(meta.arg_obj_drop.btf, + meta.arg_obj_drop.btf_id); + } else if (meta.func_id == special_kfunc_list[KF_bpf_list_pop_front] || + meta.func_id == special_kfunc_list[KF_bpf_list_pop_back]) { + struct btf_field *field = meta.arg_list_head.field; + + mark_reg_known_zero(env, regs, BPF_REG_0); + regs[BPF_REG_0].type = PTR_TO_BTF_ID | MEM_ALLOC; + regs[BPF_REG_0].btf = field->list_head.btf; + regs[BPF_REG_0].btf_id = field->list_head.value_btf_id; + regs[BPF_REG_0].off = field->list_head.node_offset; + } else if (meta.func_id == special_kfunc_list[KF_bpf_cast_to_kern_ctx]) { + mark_reg_known_zero(env, regs, BPF_REG_0); + regs[BPF_REG_0].type = PTR_TO_BTF_ID | PTR_TRUSTED; + regs[BPF_REG_0].btf = desc_btf; + regs[BPF_REG_0].btf_id = meta.ret_btf_id; + } else if (meta.func_id == special_kfunc_list[KF_bpf_rdonly_cast]) { + ret_t = btf_type_by_id(desc_btf, meta.arg_constant.value); + if (!ret_t || !btf_type_is_struct(ret_t)) { + verbose(env, + "kfunc bpf_rdonly_cast type ID argument must be of a struct\n"); + return -EINVAL; + } + + mark_reg_known_zero(env, regs, BPF_REG_0); + regs[BPF_REG_0].type = PTR_TO_BTF_ID | PTR_UNTRUSTED; + regs[BPF_REG_0].btf = desc_btf; + regs[BPF_REG_0].btf_id = meta.arg_constant.value; + } else { + verbose(env, "kernel function %s unhandled dynamic return type\n", + meta.func_name); + return -EFAULT; + } + } else if (!__btf_type_is_struct(ptr_type)) { if (!meta.r0_size) { ptr_type_name = btf_name_by_offset(desc_btf, ptr_type->name_off); @@ -7770,20 +9301,24 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, regs[BPF_REG_0].type = PTR_TO_BTF_ID; regs[BPF_REG_0].btf_id = ptr_type_id; } - if (*kfunc_flags & KF_RET_NULL) { + + if (is_kfunc_ret_null(&meta)) { regs[BPF_REG_0].type |= PTR_MAYBE_NULL; /* For mark_ptr_or_null_reg, see 93c230e3f5bd6 */ regs[BPF_REG_0].id = ++env->id_gen; } mark_btf_func_reg_size(env, BPF_REG_0, sizeof(void *)); - if (acq) { + if (is_kfunc_acquire(&meta)) { int id = acquire_reference_state(env, insn_idx); if (id < 0) return id; - regs[BPF_REG_0].id = id; + if (is_kfunc_ret_null(&meta)) + regs[BPF_REG_0].id = id; regs[BPF_REG_0].ref_obj_id = id; } + if (reg_may_point_to_spin_lock(®s[BPF_REG_0]) && !regs[BPF_REG_0].id) + regs[BPF_REG_0].id = ++env->id_gen; } /* else { add_kfunc_call() ensures it is btf_type_is_void(t) } */ nargs = btf_type_vlen(func_proto); @@ -8068,7 +9603,7 @@ do_sim: */ if (!ptr_is_dst_reg) { tmp = *dst_reg; - *dst_reg = *ptr_reg; + copy_register_state(dst_reg, ptr_reg); } ret = sanitize_speculative_path(env, NULL, env->insn_idx + 1, env->insn_idx); @@ -9211,6 +10746,11 @@ static int adjust_reg_min_max_vals(struct bpf_verifier_env *env, return err; return adjust_ptr_min_max_vals(env, insn, dst_reg, src_reg); + } else if (dst_reg->precise) { + /* if dst_reg is precise, src_reg should be precise as well */ + err = mark_chain_precision(env, insn->src_reg); + if (err) + return err; } } else { /* Pretend the src is a reg with a known value, since we only @@ -9316,7 +10856,7 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn) * to propagate min/max range. */ src_reg->id = ++env->id_gen; - *dst_reg = *src_reg; + copy_register_state(dst_reg, src_reg); dst_reg->live |= REG_LIVE_WRITTEN; dst_reg->subreg_def = DEF_NOT_SUBREG; } else { @@ -9327,7 +10867,7 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn) insn->src_reg); return -EACCES; } else if (src_reg->type == SCALAR_VALUE) { - *dst_reg = *src_reg; + copy_register_state(dst_reg, src_reg); /* Make sure ID is cleared otherwise * dst_reg min/max could be incorrectly * propagated into src_reg by find_equal_scalars() @@ -9950,17 +11490,20 @@ static void mark_ptr_or_null_reg(struct bpf_func_state *state, bool is_null) { if (type_may_be_null(reg->type) && reg->id == id && - !WARN_ON_ONCE(!reg->id)) { - if (WARN_ON_ONCE(reg->smin_value || reg->smax_value || - !tnum_equals_const(reg->var_off, 0) || - reg->off)) { - /* Old offset (both fixed and variable parts) should - * have been known-zero, because we don't allow pointer - * arithmetic on pointers that might be NULL. If we - * see this happening, don't convert the register. - */ + (is_rcu_reg(reg) || !WARN_ON_ONCE(!reg->id))) { + /* Old offset (both fixed and variable parts) should have been + * known-zero, because we don't allow pointer arithmetic on + * pointers that might be NULL. If we see this happening, don't + * convert the register. + * + * But in some cases, some helpers that return local kptrs + * advance offset for the returned pointer. In those cases, it + * is fine to expect to see reg->off. + */ + if (WARN_ON_ONCE(reg->smin_value || reg->smax_value || !tnum_equals_const(reg->var_off, 0))) + return; + if (reg->type != (PTR_TO_BTF_ID | MEM_ALLOC | PTR_MAYBE_NULL) && WARN_ON_ONCE(reg->off)) return; - } if (is_null) { reg->type = SCALAR_VALUE; /* We don't need id and ref_obj_id from this point @@ -10123,7 +11666,7 @@ static void find_equal_scalars(struct bpf_verifier_state *vstate, bpf_for_each_reg_in_vstate(vstate, state, reg, ({ if (reg->type == SCALAR_VALUE && reg->id == known_reg->id) - *reg = *known_reg; + copy_register_state(reg, known_reg); })); } @@ -10134,6 +11677,7 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env, struct bpf_verifier_state *other_branch; struct bpf_reg_state *regs = this_branch->frame[this_branch->curframe]->regs; struct bpf_reg_state *dst_reg, *other_branch_regs, *src_reg = NULL; + struct bpf_reg_state *eq_branch_regs; u8 opcode = BPF_OP(insn->code); bool is_jmp32; int pred = -1; @@ -10243,8 +11787,8 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env, /* detect if we are comparing against a constant value so we can adjust * our min/max values for our dst register. * this is only legit if both are scalars (or pointers to the same - * object, I suppose, but we don't support that right now), because - * otherwise the different base pointers mean the offsets aren't + * object, I suppose, see the PTR_MAYBE_NULL related if block below), + * because otherwise the different base pointers mean the offsets aren't * comparable. */ if (BPF_SRC(insn->code) == BPF_X) { @@ -10293,6 +11837,43 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env, find_equal_scalars(other_branch, &other_branch_regs[insn->dst_reg]); } + /* if one pointer register is compared to another pointer + * register check if PTR_MAYBE_NULL could be lifted. + * E.g. register A - maybe null + * register B - not null + * for JNE A, B, ... - A is not null in the false branch; + * for JEQ A, B, ... - A is not null in the true branch. + * + * Since PTR_TO_BTF_ID points to a kernel struct that does + * not need to be null checked by the BPF program, i.e., + * could be null even without PTR_MAYBE_NULL marking, so + * only propagate nullness when neither reg is that type. + */ + if (!is_jmp32 && BPF_SRC(insn->code) == BPF_X && + __is_pointer_value(false, src_reg) && __is_pointer_value(false, dst_reg) && + type_may_be_null(src_reg->type) != type_may_be_null(dst_reg->type) && + base_type(src_reg->type) != PTR_TO_BTF_ID && + base_type(dst_reg->type) != PTR_TO_BTF_ID) { + eq_branch_regs = NULL; + switch (opcode) { + case BPF_JEQ: + eq_branch_regs = other_branch_regs; + break; + case BPF_JNE: + eq_branch_regs = regs; + break; + default: + /* do nothing */ + break; + } + if (eq_branch_regs) { + if (type_may_be_null(src_reg->type)) + mark_ptr_not_null_reg(&eq_branch_regs[insn->src_reg]); + else + mark_ptr_not_null_reg(&eq_branch_regs[insn->dst_reg]); + } + } + /* detect if R == 0 where R is returned from bpf_map_lookup_elem(). * NOTE: these optimizations below are related with pointer comparison * which will never be JMP32. @@ -10399,8 +11980,8 @@ static int check_ld_imm(struct bpf_verifier_env *env, struct bpf_insn *insn) insn->src_reg == BPF_PSEUDO_MAP_IDX_VALUE) { dst_reg->type = PTR_TO_MAP_VALUE; dst_reg->off = aux->map_off; - if (map_value_has_spin_lock(map)) - dst_reg->id = ++env->id_gen; + WARN_ON_ONCE(map->max_entries != 1); + /* We want reg->id to be same (0) as map_value is not distinct */ } else if (insn->src_reg == BPF_PSEUDO_MAP_FD || insn->src_reg == BPF_PSEUDO_MAP_IDX) { dst_reg->type = CONST_PTR_TO_MAP; @@ -10478,11 +12059,16 @@ static int check_ld_abs(struct bpf_verifier_env *env, struct bpf_insn *insn) return err; } - if (env->cur_state->active_spin_lock) { + if (env->cur_state->active_lock.ptr) { verbose(env, "BPF_LD_[ABS|IND] cannot be used inside bpf_spin_lock-ed region\n"); return -EINVAL; } + if (env->cur_state->active_rcu_lock) { + verbose(env, "BPF_LD_[ABS|IND] cannot be used inside bpf_rcu_read_lock-ed region\n"); + return -EINVAL; + } + if (regs[ctx_reg].type != PTR_TO_CTX) { verbose(env, "at the time of BPF_LD_ABS|IND R6 != pointer to skb\n"); @@ -10684,7 +12270,7 @@ static int check_return_code(struct bpf_verifier_env *env) * 3 let S be a stack * 4 S.push(v) * 5 while S is not empty - * 6 t <- S.pop() + * 6 t <- S.peek() * 7 if t is what we're looking for: * 8 return t * 9 for all edges e in G.adjacentEdges(t) do @@ -10733,11 +12319,16 @@ static struct bpf_verifier_state_list **explored_state( return &env->explored_states[(idx ^ state->callsite) % state_htab_size(env)]; } -static void init_explored_state(struct bpf_verifier_env *env, int idx) +static void mark_prune_point(struct bpf_verifier_env *env, int idx) { env->insn_aux_data[idx].prune_point = true; } +static bool is_prune_point(struct bpf_verifier_env *env, int insn_idx) +{ + return env->insn_aux_data[insn_idx].prune_point; +} + enum { DONE_EXPLORING = 0, KEEP_EXPLORING = 1, @@ -10766,9 +12357,11 @@ static int push_insn(int t, int w, int e, struct bpf_verifier_env *env, return -EINVAL; } - if (e == BRANCH) + if (e == BRANCH) { /* mark branch target for state pruning */ - init_explored_state(env, w); + mark_prune_point(env, w); + mark_jmp_point(env, w); + } if (insn_state[w] == 0) { /* tree-edge */ @@ -10795,8 +12388,7 @@ static int push_insn(int t, int w, int e, struct bpf_verifier_env *env, return DONE_EXPLORING; } -static int visit_func_call_insn(int t, int insn_cnt, - struct bpf_insn *insns, +static int visit_func_call_insn(int t, struct bpf_insn *insns, struct bpf_verifier_env *env, bool visit_callee) { @@ -10806,10 +12398,12 @@ static int visit_func_call_insn(int t, int insn_cnt, if (ret) return ret; - if (t + 1 < insn_cnt) - init_explored_state(env, t + 1); + mark_prune_point(env, t + 1); + /* when we exit from subprog, we need to record non-linear history */ + mark_jmp_point(env, t + 1); + if (visit_callee) { - init_explored_state(env, t); + mark_prune_point(env, t); ret = push_insn(t, t + insns[t].imm + 1, BRANCH, env, /* It's ok to allow recursion from CFG point of * view. __check_func_call() will do the actual @@ -10825,13 +12419,13 @@ static int visit_func_call_insn(int t, int insn_cnt, * DONE_EXPLORING - the instruction was fully explored * KEEP_EXPLORING - there is still work to be done before it is fully explored */ -static int visit_insn(int t, int insn_cnt, struct bpf_verifier_env *env) +static int visit_insn(int t, struct bpf_verifier_env *env) { struct bpf_insn *insns = env->prog->insnsi; int ret; if (bpf_pseudo_func(insns + t)) - return visit_func_call_insn(t, insn_cnt, insns, env, true); + return visit_func_call_insn(t, insns, env, true); /* All non-branch instructions have a single fall-through edge. */ if (BPF_CLASS(insns[t].code) != BPF_JMP && @@ -10844,13 +12438,13 @@ static int visit_insn(int t, int insn_cnt, struct bpf_verifier_env *env) case BPF_CALL: if (insns[t].imm == BPF_FUNC_timer_set_callback) - /* Mark this call insn to trigger is_state_visited() check - * before call itself is processed by __check_func_call(). - * Otherwise new async state will be pushed for further - * exploration. + /* Mark this call insn as a prune point to trigger + * is_state_visited() check before call itself is + * processed by __check_func_call(). Otherwise new + * async state will be pushed for further exploration. */ - init_explored_state(env, t); - return visit_func_call_insn(t, insn_cnt, insns, env, + mark_prune_point(env, t); + return visit_func_call_insn(t, insns, env, insns[t].src_reg == BPF_PSEUDO_CALL); case BPF_JA: @@ -10863,22 +12457,15 @@ static int visit_insn(int t, int insn_cnt, struct bpf_verifier_env *env) if (ret) return ret; - /* unconditional jmp is not a good pruning point, - * but it's marked, since backtracking needs - * to record jmp history in is_state_visited(). - */ - init_explored_state(env, t + insns[t].off + 1); - /* tell verifier to check for equivalent states - * after every call and jump - */ - if (t + 1 < insn_cnt) - init_explored_state(env, t + 1); + mark_prune_point(env, t + insns[t].off + 1); + mark_jmp_point(env, t + insns[t].off + 1); return ret; default: /* conditional jump with two edges */ - init_explored_state(env, t); + mark_prune_point(env, t); + ret = push_insn(t, t + 1, FALLTHROUGH, env, true); if (ret) return ret; @@ -10914,7 +12501,7 @@ static int check_cfg(struct bpf_verifier_env *env) while (env->cfg.cur_stack > 0) { int t = insn_stack[env->cfg.cur_stack - 1]; - ret = visit_insn(t, insn_cnt, env); + ret = visit_insn(t, env); switch (ret) { case DONE_EXPLORING: insn_state[t] = EXPLORED; @@ -11505,15 +13092,6 @@ static bool regsafe(struct bpf_verifier_env *env, struct bpf_reg_state *rold, equal = memcmp(rold, rcur, offsetof(struct bpf_reg_state, parent)) == 0; - if (rold->type == PTR_TO_STACK) - /* two stack pointers are equal only if they're pointing to - * the same stack frame, since fp-8 in foo != fp-8 in bar - */ - return equal && rold->frameno == rcur->frameno; - - if (equal) - return true; - if (rold->type == NOT_INIT) /* explored state can't have used this */ return true; @@ -11521,10 +13099,12 @@ static bool regsafe(struct bpf_verifier_env *env, struct bpf_reg_state *rold, return false; switch (base_type(rold->type)) { case SCALAR_VALUE: + if (equal) + return true; if (env->explore_alu_limits) return false; if (rcur->type == SCALAR_VALUE) { - if (!rold->precise && !rcur->precise) + if (!rold->precise) return true; /* new val must satisfy old val knowledge */ return range_within(rold, rcur) && @@ -11567,7 +13147,8 @@ static bool regsafe(struct bpf_verifier_env *env, struct bpf_reg_state *rold, */ return memcmp(rold, rcur, offsetof(struct bpf_reg_state, id)) == 0 && range_within(rold, rcur) && - tnum_in(rold->var_off, rcur->var_off); + tnum_in(rold->var_off, rcur->var_off) && + check_ids(rold->id, rcur->id, idmap); case PTR_TO_PACKET_META: case PTR_TO_PACKET: if (rcur->type != rold->type) @@ -11591,20 +13172,14 @@ static bool regsafe(struct bpf_verifier_env *env, struct bpf_reg_state *rold, /* new val must satisfy old val knowledge */ return range_within(rold, rcur) && tnum_in(rold->var_off, rcur->var_off); - case PTR_TO_CTX: - case CONST_PTR_TO_MAP: - case PTR_TO_PACKET_END: - case PTR_TO_FLOW_KEYS: - case PTR_TO_SOCKET: - case PTR_TO_SOCK_COMMON: - case PTR_TO_TCP_SOCK: - case PTR_TO_XDP_SOCK: - /* Only valid matches are exact, which memcmp() above - * would have accepted + case PTR_TO_STACK: + /* two stack pointers are equal only if they're pointing to + * the same stack frame, since fp-8 in foo != fp-8 in bar */ + return equal && rold->frameno == rcur->frameno; default: - /* Don't know what's going on, just say it's not safe */ - return false; + /* Only valid matches are exact, which memcmp() */ + return equal; } /* Shouldn't get here; if we do, say it's not safe */ @@ -11714,7 +13289,6 @@ static bool func_states_equal(struct bpf_verifier_env *env, struct bpf_func_stat { int i; - memset(env->idmap_scratch, 0, sizeof(env->idmap_scratch)); for (i = 0; i < MAX_BPF_REG; i++) if (!regsafe(env, &old->regs[i], &cur->regs[i], env->idmap_scratch)) @@ -11738,13 +13312,28 @@ static bool states_equal(struct bpf_verifier_env *env, if (old->curframe != cur->curframe) return false; + memset(env->idmap_scratch, 0, sizeof(env->idmap_scratch)); + /* Verification state from speculative execution simulation * must never prune a non-speculative execution one. */ if (old->speculative && !cur->speculative) return false; - if (old->active_spin_lock != cur->active_spin_lock) + if (old->active_lock.ptr != cur->active_lock.ptr) + return false; + + /* Old and cur active_lock's have to be either both present + * or both absent. + */ + if (!!old->active_lock.id != !!cur->active_lock.id) + return false; + + if (old->active_lock.id && + !check_ids(old->active_lock.id, cur->active_lock.id, env->idmap_scratch)) + return false; + + if (old->active_rcu_lock != cur->active_rcu_lock) return false; /* for states to be equal callsites have to be the same @@ -11847,34 +13436,36 @@ static int propagate_precision(struct bpf_verifier_env *env, { struct bpf_reg_state *state_reg; struct bpf_func_state *state; - int i, err = 0; + int i, err = 0, fr; - state = old->frame[old->curframe]; - state_reg = state->regs; - for (i = 0; i < BPF_REG_FP; i++, state_reg++) { - if (state_reg->type != SCALAR_VALUE || - !state_reg->precise) - continue; - if (env->log.level & BPF_LOG_LEVEL2) - verbose(env, "propagating r%d\n", i); - err = mark_chain_precision(env, i); - if (err < 0) - return err; - } + for (fr = old->curframe; fr >= 0; fr--) { + state = old->frame[fr]; + state_reg = state->regs; + for (i = 0; i < BPF_REG_FP; i++, state_reg++) { + if (state_reg->type != SCALAR_VALUE || + !state_reg->precise) + continue; + if (env->log.level & BPF_LOG_LEVEL2) + verbose(env, "frame %d: propagating r%d\n", i, fr); + err = mark_chain_precision_frame(env, fr, i); + if (err < 0) + return err; + } - for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) { - if (!is_spilled_reg(&state->stack[i])) - continue; - state_reg = &state->stack[i].spilled_ptr; - if (state_reg->type != SCALAR_VALUE || - !state_reg->precise) - continue; - if (env->log.level & BPF_LOG_LEVEL2) - verbose(env, "propagating fp%d\n", - (-i - 1) * BPF_REG_SIZE); - err = mark_chain_precision_stack(env, i); - if (err < 0) - return err; + for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) { + if (!is_spilled_reg(&state->stack[i])) + continue; + state_reg = &state->stack[i].spilled_ptr; + if (state_reg->type != SCALAR_VALUE || + !state_reg->precise) + continue; + if (env->log.level & BPF_LOG_LEVEL2) + verbose(env, "frame %d: propagating fp%d\n", + (-i - 1) * BPF_REG_SIZE, fr); + err = mark_chain_precision_stack_frame(env, fr, i); + if (err < 0) + return err; + } } return 0; } @@ -11906,13 +13497,6 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx) int i, j, err, states_cnt = 0; bool add_new_state = env->test_state_freq ? true : false; - cur->last_insn_idx = env->prev_insn_idx; - if (!env->insn_aux_data[insn_idx].prune_point) - /* this 'insn_idx' instruction wasn't marked, so we will not - * be doing state search here - */ - return 0; - /* bpf progs typically have pruning point every 4 instructions * http://vger.kernel.org/bpfconf2019.html#session-1 * Do not add new state for future pruning if the verifier hasn't seen @@ -12047,10 +13631,10 @@ next: env->max_states_per_insn = states_cnt; if (!env->bpf_capable && states_cnt > BPF_COMPLEXITY_LIMIT_STATES) - return push_jmp_history(env, cur); + return 0; if (!add_new_state) - return push_jmp_history(env, cur); + return 0; /* There were no equivalent states, remember the current one. * Technically the current state is not proven to be safe yet, @@ -12069,6 +13653,10 @@ next: env->prev_jmps_processed = env->jmps_processed; env->prev_insn_processed = env->insn_processed; + /* forget precise markings we inherited, see __mark_chain_precision */ + if (env->bpf_capable) + mark_all_scalars_imprecise(env, cur); + /* add new state to the head of linked list */ new = &new_sl->state; err = copy_verifier_state(new, cur); @@ -12186,21 +13774,31 @@ static int do_check(struct bpf_verifier_env *env) return -E2BIG; } - err = is_state_visited(env, env->insn_idx); - if (err < 0) - return err; - if (err == 1) { - /* found equivalent state, can prune the search */ - if (env->log.level & BPF_LOG_LEVEL) { - if (do_print_state) - verbose(env, "\nfrom %d to %d%s: safe\n", - env->prev_insn_idx, env->insn_idx, - env->cur_state->speculative ? - " (speculative execution)" : ""); - else - verbose(env, "%d: safe\n", env->insn_idx); + state->last_insn_idx = env->prev_insn_idx; + + if (is_prune_point(env, env->insn_idx)) { + err = is_state_visited(env, env->insn_idx); + if (err < 0) + return err; + if (err == 1) { + /* found equivalent state, can prune the search */ + if (env->log.level & BPF_LOG_LEVEL) { + if (do_print_state) + verbose(env, "\nfrom %d to %d%s: safe\n", + env->prev_insn_idx, env->insn_idx, + env->cur_state->speculative ? + " (speculative execution)" : ""); + else + verbose(env, "%d: safe\n", env->insn_idx); + } + goto process_bpf_exit; } - goto process_bpf_exit; + } + + if (is_jmp_point(env, env->insn_idx)) { + err = push_jmp_history(env, state); + if (err) + return err; } if (signal_pending(current)) @@ -12383,11 +13981,14 @@ static int do_check(struct bpf_verifier_env *env) return -EINVAL; } - if (env->cur_state->active_spin_lock && - (insn->src_reg == BPF_PSEUDO_CALL || - insn->imm != BPF_FUNC_spin_unlock)) { - verbose(env, "function calls are not allowed while holding a lock\n"); - return -EINVAL; + if (env->cur_state->active_lock.ptr) { + if ((insn->src_reg == BPF_REG_0 && insn->imm != BPF_FUNC_spin_unlock) || + (insn->src_reg == BPF_PSEUDO_CALL) || + (insn->src_reg == BPF_PSEUDO_KFUNC_CALL && + (insn->off != 0 || !is_bpf_list_api_kfunc(insn->imm)))) { + verbose(env, "function calls are not allowed while holding a lock\n"); + return -EINVAL; + } } if (insn->src_reg == BPF_PSEUDO_CALL) err = check_func_call(env, insn, &env->insn_idx); @@ -12420,11 +14021,16 @@ static int do_check(struct bpf_verifier_env *env) return -EINVAL; } - if (env->cur_state->active_spin_lock) { + if (env->cur_state->active_lock.ptr) { verbose(env, "bpf_spin_unlock is missing\n"); return -EINVAL; } + if (env->cur_state->active_rcu_lock) { + verbose(env, "bpf_rcu_read_unlock is missing\n"); + return -EINVAL; + } + /* We must do check_reference_leak here before * prepare_func_exit to handle the case when * state->curframe > 0, it may be a callback @@ -12677,7 +14283,14 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env, { enum bpf_prog_type prog_type = resolve_prog_type(prog); - if (map_value_has_spin_lock(map)) { + if (btf_record_has_field(map->record, BPF_LIST_HEAD)) { + if (is_tracing_prog_type(prog_type)) { + verbose(env, "tracing progs cannot use bpf_list_head yet\n"); + return -EINVAL; + } + } + + if (btf_record_has_field(map->record, BPF_SPIN_LOCK)) { if (prog_type == BPF_PROG_TYPE_SOCKET_FILTER) { verbose(env, "socket filter progs cannot use bpf_spin_lock yet\n"); return -EINVAL; @@ -12694,7 +14307,7 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env, } } - if (map_value_has_timer(map)) { + if (btf_record_has_field(map->record, BPF_TIMER)) { if (is_tracing_prog_type(prog_type)) { verbose(env, "tracing progs cannot use bpf_timer yet\n"); return -EINVAL; @@ -12727,10 +14340,11 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env, case BPF_MAP_TYPE_INODE_STORAGE: case BPF_MAP_TYPE_SK_STORAGE: case BPF_MAP_TYPE_TASK_STORAGE: + case BPF_MAP_TYPE_CGRP_STORAGE: break; default: verbose(env, - "Sleepable programs can only use array, hash, and ringbuf maps\n"); + "Sleepable programs can only use array, hash, ringbuf and local storage maps\n"); return -EINVAL; } @@ -13386,6 +15000,10 @@ static int opt_subreg_zext_lo32_rnd_hi32(struct bpf_verifier_env *env, if (!bpf_jit_needs_zext() && !is_cmpxchg_insn(&insn)) continue; + /* Zero-extension is done by the caller. */ + if (bpf_pseudo_kfunc_call(&insn)) + continue; + if (WARN_ON(load_reg == -1)) { verbose(env, "verifier bug. zext_dst is set, but no reg is defined\n"); return -EFAULT; @@ -13513,6 +15131,13 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env) break; case PTR_TO_BTF_ID: case PTR_TO_BTF_ID | PTR_UNTRUSTED: + /* PTR_TO_BTF_ID | MEM_ALLOC always has a valid lifetime, unlike + * PTR_TO_BTF_ID, and an active ref_obj_id, but the same cannot + * be said once it is marked PTR_UNTRUSTED, hence we must handle + * any faults for loads into such types. BPF_WRITE is disallowed + * for this case. + */ + case PTR_TO_BTF_ID | MEM_ALLOC | PTR_UNTRUSTED: if (type == BPF_READ) { insn->code = BPF_LDX | BPF_PROBE_MEM | BPF_SIZE((insn)->code); @@ -13878,8 +15503,8 @@ static int fixup_call_args(struct bpf_verifier_env *env) return err; } -static int fixup_kfunc_call(struct bpf_verifier_env *env, - struct bpf_insn *insn) +static int fixup_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, + struct bpf_insn *insn_buf, int insn_idx, int *cnt) { const struct bpf_kfunc_desc *desc; @@ -13889,7 +15514,7 @@ static int fixup_kfunc_call(struct bpf_verifier_env *env, } /* insn->imm has the btf func_id. Replace it with - * an address (relative to __bpf_base_call). + * an address (relative to __bpf_call_base). */ desc = find_kfunc_desc(env->prog, insn->imm, insn->off); if (!desc) { @@ -13898,8 +15523,33 @@ static int fixup_kfunc_call(struct bpf_verifier_env *env, return -EFAULT; } + *cnt = 0; insn->imm = desc->imm; - + if (insn->off) + return 0; + if (desc->func_id == special_kfunc_list[KF_bpf_obj_new_impl]) { + struct btf_struct_meta *kptr_struct_meta = env->insn_aux_data[insn_idx].kptr_struct_meta; + struct bpf_insn addr[2] = { BPF_LD_IMM64(BPF_REG_2, (long)kptr_struct_meta) }; + u64 obj_new_size = env->insn_aux_data[insn_idx].obj_new_size; + + insn_buf[0] = BPF_MOV64_IMM(BPF_REG_1, obj_new_size); + insn_buf[1] = addr[0]; + insn_buf[2] = addr[1]; + insn_buf[3] = *insn; + *cnt = 4; + } else if (desc->func_id == special_kfunc_list[KF_bpf_obj_drop_impl]) { + struct btf_struct_meta *kptr_struct_meta = env->insn_aux_data[insn_idx].kptr_struct_meta; + struct bpf_insn addr[2] = { BPF_LD_IMM64(BPF_REG_2, (long)kptr_struct_meta) }; + + insn_buf[0] = addr[0]; + insn_buf[1] = addr[1]; + insn_buf[2] = *insn; + *cnt = 3; + } else if (desc->func_id == special_kfunc_list[KF_bpf_cast_to_kern_ctx] || + desc->func_id == special_kfunc_list[KF_bpf_rdonly_cast]) { + insn_buf[0] = BPF_MOV64_REG(BPF_REG_0, BPF_REG_1); + *cnt = 1; + } return 0; } @@ -14041,9 +15691,19 @@ static int do_misc_fixups(struct bpf_verifier_env *env) if (insn->src_reg == BPF_PSEUDO_CALL) continue; if (insn->src_reg == BPF_PSEUDO_KFUNC_CALL) { - ret = fixup_kfunc_call(env, insn); + ret = fixup_kfunc_call(env, insn, insn_buf, i + delta, &cnt); if (ret) return ret; + if (cnt == 0) + continue; + + new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, cnt); + if (!new_prog) + return -ENOMEM; + + delta += cnt - 1; + env->prog = prog = new_prog; + insn = new_prog->insnsi + i + delta; continue; } @@ -14161,13 +15821,12 @@ static int do_misc_fixups(struct bpf_verifier_env *env) goto patch_call_imm; } - if (insn->imm == BPF_FUNC_task_storage_get || - insn->imm == BPF_FUNC_sk_storage_get || - insn->imm == BPF_FUNC_inode_storage_get) { - if (env->prog->aux->sleepable) - insn_buf[0] = BPF_MOV64_IMM(BPF_REG_5, (__force __s32)GFP_KERNEL); - else + if (is_storage_get_function(insn->imm)) { + if (!env->prog->aux->sleepable || + env->insn_aux_data[i + delta].storage_get_func_atomic) insn_buf[0] = BPF_MOV64_IMM(BPF_REG_5, (__force __s32)GFP_ATOMIC); + else + insn_buf[0] = BPF_MOV64_IMM(BPF_REG_5, (__force __s32)GFP_KERNEL); insn_buf[1] = *insn; cnt = 2; @@ -14237,7 +15896,7 @@ static int do_misc_fixups(struct bpf_verifier_env *env) BUILD_BUG_ON(!__same_type(ops->map_peek_elem, (int (*)(struct bpf_map *map, void *value))NULL)); BUILD_BUG_ON(!__same_type(ops->map_redirect, - (int (*)(struct bpf_map *map, u32 ifindex, u64 flags))NULL)); + (int (*)(struct bpf_map *map, u64 index, u64 flags))NULL)); BUILD_BUG_ON(!__same_type(ops->map_for_each_callback, (int (*)(struct bpf_map *map, bpf_callback_t callback_fn, @@ -14616,6 +16275,8 @@ static int do_check_common(struct bpf_verifier_env *env, int subprog) BPF_MAIN_FUNC /* callsite */, 0 /* frameno */, subprog); + state->first_insn_idx = env->subprog_info[subprog].start; + state->last_insn_idx = -1; regs = state->frame[state->curframe]->regs; if (subprog || env->prog->type == BPF_PROG_TYPE_EXT) { @@ -15025,12 +16686,22 @@ int bpf_check_attach_target(struct bpf_verifier_log *log, ret = -EINVAL; switch (prog->type) { case BPF_PROG_TYPE_TRACING: - /* fentry/fexit/fmod_ret progs can be sleepable only if they are + + /* fentry/fexit/fmod_ret progs can be sleepable if they are * attached to ALLOW_ERROR_INJECTION and are not in denylist. */ if (!check_non_sleepable_error_inject(btf_id) && within_error_injection_list(addr)) ret = 0; + /* fentry/fexit/fmod_ret progs can also be sleepable if they are + * in the fmodret id set with the KF_SLEEPABLE flag. + */ + else { + u32 *flags = btf_kfunc_is_modify_return(btf, btf_id); + + if (flags && (*flags & KF_SLEEPABLE)) + ret = 0; + } break; case BPF_PROG_TYPE_LSM: /* LSM progs check that they are attached to bpf_lsm_*() funcs. @@ -15051,7 +16722,10 @@ int bpf_check_attach_target(struct bpf_verifier_log *log, bpf_log(log, "can't modify return codes of BPF programs\n"); return -EINVAL; } - ret = check_attach_modify_return(addr, tname); + ret = -EINVAL; + if (btf_kfunc_is_modify_return(btf, btf_id) || + !check_attach_modify_return(addr, tname)) + ret = 0; if (ret) { bpf_log(log, "%s() is not modifiable\n", tname); return ret; @@ -15240,10 +16914,11 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr) env->allow_ptr_leaks = bpf_allow_ptr_leaks(); env->allow_uninit_stack = bpf_allow_uninit_stack(); - env->allow_ptr_to_map_access = bpf_allow_ptr_to_map_access(); env->bypass_spec_v1 = bpf_bypass_spec_v1(); env->bypass_spec_v4 = bpf_bypass_spec_v4(); env->bpf_capable = bpf_capable(); + env->rcu_tag_supported = btf_vmlinux && + btf_find_by_name_kind(btf_vmlinux, "rcu", BTF_KIND_TYPE_TAG) > 0; if (is_priv) env->test_state_freq = attr->prog_flags & BPF_F_TEST_STATE_FREQ; diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 15cc26513596..c099cf3fa02d 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -5353,6 +5353,7 @@ static void css_free_rwork_fn(struct work_struct *work) atomic_dec(&cgrp->root->nr_cgrps); cgroup1_pidlist_destroy_all(cgrp); cancel_work_sync(&cgrp->release_agent_work); + bpf_cgrp_storage_free(cgrp); if (cgroup_parent(cgrp)) { /* diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index 589827ccda8b..ca826bd1eba3 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -1205,12 +1205,13 @@ void rebuild_sched_domains(void) /** * update_tasks_cpumask - Update the cpumasks of tasks in the cpuset. * @cs: the cpuset in which each task's cpus_allowed mask needs to be changed + * @new_cpus: the temp variable for the new effective_cpus mask * * Iterate through each task of @cs updating its cpus_allowed to the * effective cpuset's. As this function is called with cpuset_rwsem held, * cpuset membership stays stable. */ -static void update_tasks_cpumask(struct cpuset *cs) +static void update_tasks_cpumask(struct cpuset *cs, struct cpumask *new_cpus) { struct css_task_iter it; struct task_struct *task; @@ -1224,7 +1225,10 @@ static void update_tasks_cpumask(struct cpuset *cs) if (top_cs && (task->flags & PF_KTHREAD) && kthread_is_per_cpu(task)) continue; - set_cpus_allowed_ptr(task, cs->effective_cpus); + + cpumask_and(new_cpus, cs->effective_cpus, + task_cpu_possible_mask(task)); + set_cpus_allowed_ptr(task, new_cpus); } css_task_iter_end(&it); } @@ -1346,7 +1350,7 @@ static int update_parent_subparts_cpumask(struct cpuset *cs, int cmd, * A parent can be left with no CPU as long as there is no * task directly associated with the parent partition. */ - if (!cpumask_intersects(cs->cpus_allowed, parent->effective_cpus) && + if (cpumask_subset(parent->effective_cpus, cs->cpus_allowed) && partition_is_populated(parent, cs)) return PERR_NOCPUS; @@ -1509,7 +1513,7 @@ static int update_parent_subparts_cpumask(struct cpuset *cs, int cmd, spin_unlock_irq(&callback_lock); if (adding || deleting) - update_tasks_cpumask(parent); + update_tasks_cpumask(parent, tmp->new_cpus); /* * Set or clear CS_SCHED_LOAD_BALANCE when partcmd_update, if necessary. @@ -1661,7 +1665,7 @@ update_parent_subparts: WARN_ON(!is_in_v2_mode() && !cpumask_equal(cp->cpus_allowed, cp->effective_cpus)); - update_tasks_cpumask(cp); + update_tasks_cpumask(cp, tmp->new_cpus); /* * On legacy hierarchy, if the effective cpumask of any non- @@ -2309,7 +2313,7 @@ static int update_prstate(struct cpuset *cs, int new_prs) } } - update_tasks_cpumask(parent); + update_tasks_cpumask(parent, tmpmask.new_cpus); if (parent->child_ecpus_count) update_sibling_cpumasks(parent, cs, &tmpmask); @@ -2324,6 +2328,7 @@ out: new_prs = -new_prs; spin_lock_irq(&callback_lock); cs->partition_root_state = new_prs; + WRITE_ONCE(cs->prs_err, err); spin_unlock_irq(&callback_lock); /* * Update child cpusets, if present. @@ -3347,7 +3352,7 @@ hotplug_update_tasks_legacy(struct cpuset *cs, * as the tasks will be migrated to an ancestor. */ if (cpus_updated && !cpumask_empty(cs->cpus_allowed)) - update_tasks_cpumask(cs); + update_tasks_cpumask(cs, new_cpus); if (mems_updated && !nodes_empty(cs->mems_allowed)) update_tasks_nodemask(cs); @@ -3384,7 +3389,7 @@ hotplug_update_tasks(struct cpuset *cs, spin_unlock_irq(&callback_lock); if (cpus_updated) - update_tasks_cpumask(cs); + update_tasks_cpumask(cs, new_cpus); if (mems_updated) update_tasks_nodemask(cs); } @@ -3660,11 +3665,6 @@ static int cpuset_track_online_nodes(struct notifier_block *self, return NOTIFY_OK; } -static struct notifier_block cpuset_track_online_nodes_nb = { - .notifier_call = cpuset_track_online_nodes, - .priority = 10, /* ??! */ -}; - /** * cpuset_init_smp - initialize cpus_allowed * @@ -3682,7 +3682,7 @@ void __init cpuset_init_smp(void) cpumask_copy(top_cpuset.effective_cpus, cpu_active_mask); top_cpuset.effective_mems = node_states[N_MEMORY]; - register_hotmemory_notifier(&cpuset_track_online_nodes_nb); + hotplug_memory_notifier(cpuset_track_online_nodes, CPUSET_CALLBACK_PRI); cpuset_migrate_mm_wq = alloc_ordered_workqueue("cpuset_migrate_mm", 0); BUG_ON(!cpuset_migrate_mm_wq); @@ -3696,15 +3696,38 @@ void __init cpuset_init_smp(void) * Description: Returns the cpumask_var_t cpus_allowed of the cpuset * attached to the specified @tsk. Guaranteed to return some non-empty * subset of cpu_online_mask, even if this means going outside the - * tasks cpuset. + * tasks cpuset, except when the task is in the top cpuset. **/ void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask) { unsigned long flags; + struct cpuset *cs; spin_lock_irqsave(&callback_lock, flags); - guarantee_online_cpus(tsk, pmask); + rcu_read_lock(); + + cs = task_cs(tsk); + if (cs != &top_cpuset) + guarantee_online_cpus(tsk, pmask); + /* + * Tasks in the top cpuset won't get update to their cpumasks + * when a hotplug online/offline event happens. So we include all + * offline cpus in the allowed cpu list. + */ + if ((cs == &top_cpuset) || cpumask_empty(pmask)) { + const struct cpumask *possible_mask = task_cpu_possible_mask(tsk); + + /* + * We first exclude cpus allocated to partitions. If there is no + * allowable online cpu left, we fall back to all possible cpus. + */ + cpumask_andnot(pmask, possible_mask, top_cpuset.subparts_cpus); + if (!cpumask_intersects(pmask, cpu_online_mask)) + cpumask_copy(pmask, possible_mask); + } + + rcu_read_unlock(); spin_unlock_irqrestore(&callback_lock, flags); } diff --git a/kernel/cred.c b/kernel/cred.c index e10c15f51c1f..811ad654abd1 100644 --- a/kernel/cred.c +++ b/kernel/cred.c @@ -701,9 +701,9 @@ void __init cred_init(void) * override a task's own credentials so that work can be done on behalf of that * task that requires a different subjective context. * - * @daemon is used to provide a base for the security record, but can be NULL. - * If @daemon is supplied, then the security data will be derived from that; - * otherwise they'll be set to 0 and no groups, full capabilities and no keys. + * @daemon is used to provide a base cred, with the security data derived from + * that; if this is "&init_task", they'll be set to 0, no groups, full + * capabilities, and no keys. * * The caller may change these controls afterwards if desired. * @@ -714,17 +714,16 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon) const struct cred *old; struct cred *new; + if (WARN_ON_ONCE(!daemon)) + return NULL; + new = kmem_cache_alloc(cred_jar, GFP_KERNEL); if (!new) return NULL; kdebug("prepare_kernel_cred() alloc %p", new); - if (daemon) - old = get_task_cred(daemon); - else - old = get_cred(&init_cred); - + old = get_task_cred(daemon); validate_creds(old); *new = *old; diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index c026a5a5e046..68106e3791f6 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -560,6 +560,8 @@ static struct page *__dma_alloc_pages(struct device *dev, size_t size, return NULL; if (WARN_ON_ONCE(gfp & (__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM))) return NULL; + if (WARN_ON_ONCE(gfp & __GFP_COMP)) + return NULL; size = PAGE_ALIGN(size); if (dma_alloc_direct(dev, ops)) @@ -645,6 +647,8 @@ struct sg_table *dma_alloc_noncontiguous(struct device *dev, size_t size, if (WARN_ON_ONCE(attrs & ~DMA_ATTR_ALLOC_SINGLE_PAGES)) return NULL; + if (WARN_ON_ONCE(gfp & __GFP_COMP)) + return NULL; if (ops && ops->alloc_noncontiguous) sgt = ops->alloc_noncontiguous(dev, size, dir, gfp, attrs); diff --git a/kernel/events/core.c b/kernel/events/core.c index e47914ac8732..c4be13e50547 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -380,7 +380,6 @@ enum event_type_t { /* * perf_sched_events : >0 events exist - * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu */ static void perf_sched_delayed(struct work_struct *work); @@ -389,7 +388,6 @@ static DECLARE_DELAYED_WORK(perf_sched_work, perf_sched_delayed); static DEFINE_MUTEX(perf_sched_mutex); static atomic_t perf_sched_count; -static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events); static atomic_t nr_mmap_events __read_mostly; @@ -844,9 +842,16 @@ static void perf_cgroup_switch(struct task_struct *task) struct perf_cpu_context *cpuctx = this_cpu_ptr(&perf_cpu_context); struct perf_cgroup *cgrp; - cgrp = perf_cgroup_from_task(task, NULL); + /* + * cpuctx->cgrp is set when the first cgroup event enabled, + * and is cleared when the last cgroup event disabled. + */ + if (READ_ONCE(cpuctx->cgrp) == NULL) + return; WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); + + cgrp = perf_cgroup_from_task(task, NULL); if (READ_ONCE(cpuctx->cgrp) == cgrp) return; @@ -3631,8 +3636,7 @@ void __perf_event_task_sched_out(struct task_struct *task, * to check if we have to switch out PMU state. * cgroup event are system-wide mode only */ - if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) - perf_cgroup_switch(next); + perf_cgroup_switch(next); } static bool perf_less_group_idx(const void *l, const void *r) @@ -4809,19 +4813,17 @@ find_get_pmu_context(struct pmu *pmu, struct perf_event_context *ctx, cpc = per_cpu_ptr(pmu->cpu_pmu_context, event->cpu); epc = &cpc->epc; - + raw_spin_lock_irq(&ctx->lock); if (!epc->ctx) { atomic_set(&epc->refcount, 1); epc->embedded = 1; - raw_spin_lock_irq(&ctx->lock); list_add(&epc->pmu_ctx_entry, &ctx->pmu_ctx_list); epc->ctx = ctx; - raw_spin_unlock_irq(&ctx->lock); } else { WARN_ON_ONCE(epc->ctx != ctx); atomic_inc(&epc->refcount); } - + raw_spin_unlock_irq(&ctx->lock); return epc; } @@ -4892,33 +4894,30 @@ static void free_epc_rcu(struct rcu_head *head) static void put_pmu_ctx(struct perf_event_pmu_context *epc) { + struct perf_event_context *ctx = epc->ctx; unsigned long flags; - if (!atomic_dec_and_test(&epc->refcount)) + /* + * XXX + * + * lockdep_assert_held(&ctx->mutex); + * + * can't because of the call-site in _free_event()/put_event() + * which isn't always called under ctx->mutex. + */ + if (!atomic_dec_and_raw_lock_irqsave(&epc->refcount, &ctx->lock, flags)) return; - if (epc->ctx) { - struct perf_event_context *ctx = epc->ctx; - - /* - * XXX - * - * lockdep_assert_held(&ctx->mutex); - * - * can't because of the call-site in _free_event()/put_event() - * which isn't always called under ctx->mutex. - */ + WARN_ON_ONCE(list_empty(&epc->pmu_ctx_entry)); - WARN_ON_ONCE(list_empty(&epc->pmu_ctx_entry)); - raw_spin_lock_irqsave(&ctx->lock, flags); - list_del_init(&epc->pmu_ctx_entry); - epc->ctx = NULL; - raw_spin_unlock_irqrestore(&ctx->lock, flags); - } + list_del_init(&epc->pmu_ctx_entry); + epc->ctx = NULL; WARN_ON_ONCE(!list_empty(&epc->pinned_active)); WARN_ON_ONCE(!list_empty(&epc->flexible_active)); + raw_spin_unlock_irqrestore(&ctx->lock, flags); + if (epc->embedded) return; @@ -4974,15 +4973,6 @@ static void unaccount_pmu_sb_event(struct perf_event *event) detach_sb_event(event); } -static void unaccount_event_cpu(struct perf_event *event, int cpu) -{ - if (event->parent) - return; - - if (is_cgroup_event(event)) - atomic_dec(&per_cpu(perf_cgroup_events, cpu)); -} - #ifdef CONFIG_NO_HZ_FULL static DEFINE_SPINLOCK(nr_freq_lock); #endif @@ -5048,8 +5038,6 @@ static void unaccount_event(struct perf_event *event) schedule_delayed_work(&perf_sched_work, HZ); } - unaccount_event_cpu(event, event->cpu); - unaccount_pmu_sb_event(event); } @@ -7493,7 +7481,7 @@ static u64 perf_get_pgtable_size(struct mm_struct *mm, unsigned long addr) return pud_leaf_size(pud); pmdp = pmd_offset_lockless(pudp, pud, addr); - pmd = READ_ONCE(*pmdp); + pmd = pmdp_get_lockless(pmdp); if (!pmd_present(pmd)) return 0; @@ -11679,15 +11667,6 @@ static void account_pmu_sb_event(struct perf_event *event) attach_sb_event(event); } -static void account_event_cpu(struct perf_event *event, int cpu) -{ - if (event->parent) - return; - - if (is_cgroup_event(event)) - atomic_inc(&per_cpu(perf_cgroup_events, cpu)); -} - /* Freq events need the tick to stay alive (see perf_event_task_tick). */ static void account_freq_event_nohz(void) { @@ -11775,8 +11754,6 @@ static void account_event(struct perf_event *event) } enabled: - account_event_cpu(event, event->cpu); - account_pmu_sb_event(event); } @@ -12339,12 +12316,12 @@ SYSCALL_DEFINE5(perf_event_open, if (flags & ~PERF_FLAG_ALL) return -EINVAL; - /* Do we allow access to perf_event_open(2) ? */ - err = security_perf_event_open(&attr, PERF_SECURITY_OPEN); + err = perf_copy_attr(attr_uptr, &attr); if (err) return err; - err = perf_copy_attr(attr_uptr, &attr); + /* Do we allow access to perf_event_open(2) ? */ + err = security_perf_event_open(&attr, PERF_SECURITY_OPEN); if (err) return err; @@ -12689,7 +12666,8 @@ SYSCALL_DEFINE5(perf_event_open, return event_fd; err_context: - /* event->pmu_ctx freed by free_event() */ + put_pmu_ctx(event->pmu_ctx); + event->pmu_ctx = NULL; /* _free_event() */ err_locked: mutex_unlock(&ctx->mutex); perf_unpin_context(ctx); @@ -12802,6 +12780,7 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, err_pmu_ctx: put_pmu_ctx(pmu_ctx); + event->pmu_ctx = NULL; /* _free_event() */ err_unlock: mutex_unlock(&ctx->mutex); perf_unpin_context(ctx); @@ -12822,13 +12801,11 @@ static void __perf_pmu_remove(struct perf_event_context *ctx, perf_event_groups_for_cpu_pmu(event, groups, cpu, pmu) { perf_remove_from_context(event, 0); - unaccount_event_cpu(event, cpu); put_pmu_ctx(event->pmu_ctx); list_add(&event->migrate_entry, events); for_each_sibling_event(sibling, event) { perf_remove_from_context(sibling, 0); - unaccount_event_cpu(sibling, cpu); put_pmu_ctx(sibling->pmu_ctx); list_add(&sibling->migrate_entry, events); } @@ -12847,7 +12824,6 @@ static void __perf_pmu_install_event(struct pmu *pmu, if (event->state >= PERF_EVENT_STATE_OFF) event->state = PERF_EVENT_STATE_INACTIVE; - account_event_cpu(event, cpu); perf_install_in_context(ctx, event, cpu); } @@ -13231,7 +13207,7 @@ inherit_event(struct perf_event *parent_event, pmu_ctx = find_get_pmu_context(child_event->pmu, child_ctx, child_event); if (IS_ERR(pmu_ctx)) { free_event(child_event); - return NULL; + return ERR_CAST(pmu_ctx); } child_event->pmu_ctx = pmu_ctx; @@ -13742,8 +13718,7 @@ static int __perf_cgroup_move(void *info) struct task_struct *task = info; preempt_disable(); - if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) - perf_cgroup_switch(task); + perf_cgroup_switch(task); preempt_enable(); return 0; diff --git a/kernel/exit.c b/kernel/exit.c index 35e0a31a0315..15dc2ec80c46 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -67,11 +67,58 @@ #include <linux/io_uring.h> #include <linux/kprobes.h> #include <linux/rethook.h> +#include <linux/sysfs.h> #include <linux/uaccess.h> #include <asm/unistd.h> #include <asm/mmu_context.h> +/* + * The default value should be high enough to not crash a system that randomly + * crashes its kernel from time to time, but low enough to at least not permit + * overflowing 32-bit refcounts or the ldsem writer count. + */ +static unsigned int oops_limit = 10000; + +#ifdef CONFIG_SYSCTL +static struct ctl_table kern_exit_table[] = { + { + .procname = "oops_limit", + .data = &oops_limit, + .maxlen = sizeof(oops_limit), + .mode = 0644, + .proc_handler = proc_douintvec, + }, + { } +}; + +static __init int kernel_exit_sysctls_init(void) +{ + register_sysctl_init("kernel", kern_exit_table); + return 0; +} +late_initcall(kernel_exit_sysctls_init); +#endif + +static atomic_t oops_count = ATOMIC_INIT(0); + +#ifdef CONFIG_SYSFS +static ssize_t oops_count_show(struct kobject *kobj, struct kobj_attribute *attr, + char *page) +{ + return sysfs_emit(page, "%d\n", atomic_read(&oops_count)); +} + +static struct kobj_attribute oops_count_attr = __ATTR_RO(oops_count); + +static __init int kernel_exit_sysfs_init(void) +{ + sysfs_add_file_to_group(kernel_kobj, &oops_count_attr.attr, NULL); + return 0; +} +late_initcall(kernel_exit_sysfs_init); +#endif + static void __unhash_process(struct task_struct *p, bool group_dead) { nr_threads--; @@ -884,6 +931,7 @@ void __noreturn make_task_dead(int signr) * Then do everything else. */ struct task_struct *tsk = current; + unsigned int limit; if (unlikely(in_interrupt())) panic("Aiee, killing interrupt handler!"); @@ -898,6 +946,20 @@ void __noreturn make_task_dead(int signr) } /* + * Every time the system oopses, if the oops happens while a reference + * to an object was held, the reference leaks. + * If the oops doesn't also leak memory, repeated oopsing can cause + * reference counters to wrap around (if they're not using refcount_t). + * This means that repeated oopsing can make unexploitable-looking bugs + * exploitable through repeated oopsing. + * To make sure this can't happen, place an upper bound on how often the + * kernel may oops without panic(). + */ + limit = READ_ONCE(oops_limit); + if (atomic_inc_return(&oops_count) >= limit && limit) + panic("Oopsed too often (kernel.oops_limit is %d)", limit); + + /* * We're taking recursive faults here in make_task_dead. Safest is to just * leave this task alone and wait for reboot. */ diff --git a/kernel/fork.c b/kernel/fork.c index 89b8b6c08592..9f7fe3541897 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -756,8 +756,13 @@ static void check_mm(struct mm_struct *mm) "Please make sure 'struct resident_page_types[]' is updated as well"); for (i = 0; i < NR_MM_COUNTERS; i++) { - long x = atomic_long_read(&mm->rss_stat.count[i]); + long x = percpu_counter_sum(&mm->rss_stat[i]); + if (likely(!x)) + continue; + + /* Making sure this is not due to race with CPU offlining. */ + x = percpu_counter_sum_all(&mm->rss_stat[i]); if (unlikely(x)) pr_alert("BUG: Bad rss-counter state mm:%p type:%s val:%ld\n", mm, resident_page_types[i], x); @@ -782,6 +787,8 @@ static void check_mm(struct mm_struct *mm) */ void __mmdrop(struct mm_struct *mm) { + int i; + BUG_ON(mm == &init_mm); WARN_ON_ONCE(mm == current->mm); WARN_ON_ONCE(mm == current->active_mm); @@ -791,6 +798,9 @@ void __mmdrop(struct mm_struct *mm) check_mm(mm); put_user_ns(mm->user_ns); mm_pasid_drop(mm); + + for (i = 0; i < NR_MM_COUNTERS; i++) + percpu_counter_destroy(&mm->rss_stat[i]); free_mm(mm); } EXPORT_SYMBOL_GPL(__mmdrop); @@ -1110,6 +1120,8 @@ static void mm_init_uprobes_state(struct mm_struct *mm) static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p, struct user_namespace *user_ns) { + int i; + mt_init_flags(&mm->mm_mt, MM_MT_FLAGS); mt_set_external_lock(&mm->mm_mt, &mm->mmap_lock); atomic_set(&mm->mm_users, 1); @@ -1151,10 +1163,17 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p, if (init_new_context(p, mm)) goto fail_nocontext; + for (i = 0; i < NR_MM_COUNTERS; i++) + if (percpu_counter_init(&mm->rss_stat[i], 0, GFP_KERNEL_ACCOUNT)) + goto fail_pcpu; + mm->user_ns = get_user_ns(user_ns); lru_gen_init_mm(mm); return mm; +fail_pcpu: + while (i > 0) + percpu_counter_destroy(&mm->rss_stat[--i]); fail_nocontext: mm_free_pgd(mm); fail_nopgd: @@ -2588,11 +2607,6 @@ struct task_struct * __init fork_idle(int cpu) return task; } -struct mm_struct *copy_init_mm(void) -{ - return dup_mm(NULL, &init_mm); -} - /* * This is like kernel_clone(), but shaved down and tailored to just * creating io_uring workers. It returns a created task, or an error pointer. @@ -3011,10 +3025,27 @@ static void sighand_ctor(void *data) init_waitqueue_head(&sighand->signalfd_wqh); } -void __init proc_caches_init(void) +void __init mm_cache_init(void) { unsigned int mm_size; + /* + * The mm_cpumask is located at the end of mm_struct, and is + * dynamically sized based on the maximum CPU number this system + * can have, taking hotplug into account (nr_cpu_ids). + */ + mm_size = sizeof(struct mm_struct) + cpumask_size(); + + mm_cachep = kmem_cache_create_usercopy("mm_struct", + mm_size, ARCH_MIN_MMSTRUCT_ALIGN, + SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_ACCOUNT, + offsetof(struct mm_struct, saved_auxv), + sizeof_field(struct mm_struct, saved_auxv), + NULL); +} + +void __init proc_caches_init(void) +{ sighand_cachep = kmem_cache_create("sighand_cache", sizeof(struct sighand_struct), 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_TYPESAFE_BY_RCU| @@ -3032,19 +3063,6 @@ void __init proc_caches_init(void) SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_ACCOUNT, NULL); - /* - * The mm_cpumask is located at the end of mm_struct, and is - * dynamically sized based on the maximum CPU number this system - * can have, taking hotplug into account (nr_cpu_ids). - */ - mm_size = sizeof(struct mm_struct) + cpumask_size(); - - mm_cachep = kmem_cache_create_usercopy("mm_struct", - mm_size, ARCH_MIN_MMSTRUCT_ALIGN, - SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_ACCOUNT, - offsetof(struct mm_struct, saved_auxv), - sizeof_field(struct mm_struct, saved_auxv), - NULL); vm_area_cachep = KMEM_CACHE(vm_area_struct, SLAB_PANIC|SLAB_ACCOUNT); mmap_init(); nsproxy_cache_init(); diff --git a/kernel/futex/syscalls.c b/kernel/futex/syscalls.c index 086a22d1adb7..a8074079b09e 100644 --- a/kernel/futex/syscalls.c +++ b/kernel/futex/syscalls.c @@ -286,19 +286,22 @@ SYSCALL_DEFINE5(futex_waitv, struct futex_waitv __user *, waiters, } futexv = kcalloc(nr_futexes, sizeof(*futexv), GFP_KERNEL); - if (!futexv) - return -ENOMEM; + if (!futexv) { + ret = -ENOMEM; + goto destroy_timer; + } ret = futex_parse_waitv(futexv, waiters, nr_futexes); if (!ret) ret = futex_wait_multiple(futexv, nr_futexes, timeout ? &to : NULL); + kfree(futexv); + +destroy_timer: if (timeout) { hrtimer_cancel(&to.timer); destroy_hrtimer_on_stack(&to.timer); } - - kfree(futexv); return ret; } diff --git a/kernel/gcov/gcc_4_7.c b/kernel/gcov/gcc_4_7.c index 7971e989e425..74a4ef1da9ad 100644 --- a/kernel/gcov/gcc_4_7.c +++ b/kernel/gcov/gcc_4_7.c @@ -82,6 +82,7 @@ struct gcov_fn_info { * @version: gcov version magic indicating the gcc version used for compilation * @next: list head for a singly-linked list * @stamp: uniquifying time stamp + * @checksum: unique object checksum * @filename: name of the associated gcov data file * @merge: merge functions (null for unused counter type) * @n_functions: number of instrumented functions @@ -94,6 +95,10 @@ struct gcov_info { unsigned int version; struct gcov_info *next; unsigned int stamp; + /* Since GCC 12.1 a checksum field is added. */ +#if (__GNUC__ >= 12) + unsigned int checksum; +#endif const char *filename; void (*merge[GCOV_COUNTERS])(gcov_type *, unsigned int); unsigned int n_functions; diff --git a/kernel/gen_kheaders.sh b/kernel/gen_kheaders.sh index 473036b43c83..81b97f0f6556 100755 --- a/kernel/gen_kheaders.sh +++ b/kernel/gen_kheaders.sh @@ -14,6 +14,8 @@ include/ arch/$SRCARCH/include/ " +type cpio > /dev/null + # Support incremental builds by skipping archive generation # if timestamps of files being archived are not changed. diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 8fe1da9614ee..798a9042421f 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -114,7 +114,7 @@ void irq_domain_free_fwnode(struct fwnode_handle *fwnode) { struct irqchip_fwid *fwid; - if (WARN_ON(!is_fwnode_irqchip(fwnode))) + if (!fwnode || WARN_ON(!is_fwnode_irqchip(fwnode))) return; fwid = container_of(fwnode, struct irqchip_fwid, fwnode); @@ -1915,7 +1915,7 @@ static void debugfs_add_domain_dir(struct irq_domain *d) static void debugfs_remove_domain_dir(struct irq_domain *d) { - debugfs_remove(debugfs_lookup(d->name, domain_dir)); + debugfs_lookup_and_remove(d->name, domain_dir); } void __init irq_domain_debugfs_init(struct dentry *root) diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c index bd4d4dd626b4..783a3e6a0b10 100644 --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -165,7 +165,8 @@ static bool msi_ctrl_valid(struct device *dev, struct msi_ctrl *ctrl) unsigned int hwsize; if (WARN_ON_ONCE(ctrl->domid >= MSI_MAX_DEVICE_IRQDOMAINS || - !dev->msi.data->__domains[ctrl->domid].domain)) + (dev->msi.domain && + !dev->msi.data->__domains[ctrl->domid].domain))) return false; hwsize = msi_domain_get_hwsize(dev, ctrl->domid); @@ -609,8 +610,8 @@ static unsigned int msi_domain_get_hwsize(struct device *dev, unsigned int domid info = domain->host_data; return info->hwsize; } - /* No domain, no size... */ - return 0; + /* No domain, default to MSI_XA_DOMAIN_SIZE */ + return MSI_XA_DOMAIN_SIZE; } static inline void irq_chip_write_msi_msg(struct irq_data *data, @@ -999,7 +1000,7 @@ bool msi_create_device_irq_domain(struct device *dev, unsigned int domid, fail: msi_unlock_descs(dev); free_fwnode: - kfree(fwnode); + irq_domain_free_fwnode(fwnode); free_bundle: kfree(bundle); return false; @@ -1012,6 +1013,7 @@ free_bundle: */ void msi_remove_device_irq_domain(struct device *dev, unsigned int domid) { + struct fwnode_handle *fwnode = NULL; struct msi_domain_info *info; struct irq_domain *domain; @@ -1024,7 +1026,10 @@ void msi_remove_device_irq_domain(struct device *dev, unsigned int domid) dev->msi.data->__domains[domid].domain = NULL; info = domain->host_data; + if (irq_domain_is_msi_device(domain)) + fwnode = domain->fwnode; irq_domain_remove(domain); + irq_domain_free_fwnode(fwnode); kfree(container_of(info, struct msi_domain_template, info)); unlock: diff --git a/kernel/jump_label.c b/kernel/jump_label.c index 4d6c6f5f60db..d9c822bbffb8 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -113,9 +113,40 @@ int static_key_count(struct static_key *key) } EXPORT_SYMBOL_GPL(static_key_count); -void static_key_slow_inc_cpuslocked(struct static_key *key) +/* + * static_key_fast_inc_not_disabled - adds a user for a static key + * @key: static key that must be already enabled + * + * The caller must make sure that the static key can't get disabled while + * in this function. It doesn't patch jump labels, only adds a user to + * an already enabled static key. + * + * Returns true if the increment was done. Unlike refcount_t the ref counter + * is not saturated, but will fail to increment on overflow. + */ +bool static_key_fast_inc_not_disabled(struct static_key *key) { + int v; + STATIC_KEY_CHECK_USE(key); + /* + * Negative key->enabled has a special meaning: it sends + * static_key_slow_inc() down the slow path, and it is non-zero + * so it counts as "enabled" in jump_label_update(). Note that + * atomic_inc_unless_negative() checks >= 0, so roll our own. + */ + v = atomic_read(&key->enabled); + do { + if (v <= 0 || (v + 1) < 0) + return false; + } while (!likely(atomic_try_cmpxchg(&key->enabled, &v, v + 1))); + + return true; +} +EXPORT_SYMBOL_GPL(static_key_fast_inc_not_disabled); + +bool static_key_slow_inc_cpuslocked(struct static_key *key) +{ lockdep_assert_cpus_held(); /* @@ -124,15 +155,9 @@ void static_key_slow_inc_cpuslocked(struct static_key *key) * jump_label_update() process. At the same time, however, * the jump_label_update() call below wants to see * static_key_enabled(&key) for jumps to be updated properly. - * - * So give a special meaning to negative key->enabled: it sends - * static_key_slow_inc() down the slow path, and it is non-zero - * so it counts as "enabled" in jump_label_update(). Note that - * atomic_inc_unless_negative() checks >= 0, so roll our own. */ - for (int v = atomic_read(&key->enabled); v > 0; ) - if (likely(atomic_try_cmpxchg(&key->enabled, &v, v + 1))) - return; + if (static_key_fast_inc_not_disabled(key)) + return true; jump_label_lock(); if (atomic_read(&key->enabled) == 0) { @@ -144,16 +169,23 @@ void static_key_slow_inc_cpuslocked(struct static_key *key) */ atomic_set_release(&key->enabled, 1); } else { - atomic_inc(&key->enabled); + if (WARN_ON_ONCE(!static_key_fast_inc_not_disabled(key))) { + jump_label_unlock(); + return false; + } } jump_label_unlock(); + return true; } -void static_key_slow_inc(struct static_key *key) +bool static_key_slow_inc(struct static_key *key) { + bool ret; + cpus_read_lock(); - static_key_slow_inc_cpuslocked(key); + ret = static_key_slow_inc_cpuslocked(key); cpus_read_unlock(); + return ret; } EXPORT_SYMBOL_GPL(static_key_slow_inc); diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index 60c20f301a6b..83f499182c9a 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -146,7 +146,7 @@ static unsigned int get_symbol_offset(unsigned long pos) return name - kallsyms_names; } -static unsigned long kallsyms_sym_address(int idx) +unsigned long kallsyms_sym_address(int idx) { if (!IS_ENABLED(CONFIG_KALLSYMS_BASE_RELATIVE)) return kallsyms_addresses[idx]; @@ -187,26 +187,100 @@ static bool cleanup_symbol_name(char *s) return false; } +static int compare_symbol_name(const char *name, char *namebuf) +{ + int ret; + + ret = strcmp(name, namebuf); + if (!ret) + return ret; + + if (cleanup_symbol_name(namebuf) && !strcmp(name, namebuf)) + return 0; + + return ret; +} + +static unsigned int get_symbol_seq(int index) +{ + unsigned int i, seq = 0; + + for (i = 0; i < 3; i++) + seq = (seq << 8) | kallsyms_seqs_of_names[3 * index + i]; + + return seq; +} + +static int kallsyms_lookup_names(const char *name, + unsigned int *start, + unsigned int *end) +{ + int ret; + int low, mid, high; + unsigned int seq, off; + char namebuf[KSYM_NAME_LEN]; + + low = 0; + high = kallsyms_num_syms - 1; + + while (low <= high) { + mid = low + (high - low) / 2; + seq = get_symbol_seq(mid); + off = get_symbol_offset(seq); + kallsyms_expand_symbol(off, namebuf, ARRAY_SIZE(namebuf)); + ret = compare_symbol_name(name, namebuf); + if (ret > 0) + low = mid + 1; + else if (ret < 0) + high = mid - 1; + else + break; + } + + if (low > high) + return -ESRCH; + + low = mid; + while (low) { + seq = get_symbol_seq(low - 1); + off = get_symbol_offset(seq); + kallsyms_expand_symbol(off, namebuf, ARRAY_SIZE(namebuf)); + if (compare_symbol_name(name, namebuf)) + break; + low--; + } + *start = low; + + if (end) { + high = mid; + while (high < kallsyms_num_syms - 1) { + seq = get_symbol_seq(high + 1); + off = get_symbol_offset(seq); + kallsyms_expand_symbol(off, namebuf, ARRAY_SIZE(namebuf)); + if (compare_symbol_name(name, namebuf)) + break; + high++; + } + *end = high; + } + + return 0; +} + /* Lookup the address for this symbol. Returns 0 if not found. */ unsigned long kallsyms_lookup_name(const char *name) { - char namebuf[KSYM_NAME_LEN]; - unsigned long i; - unsigned int off; + int ret; + unsigned int i; /* Skip the search for empty string. */ if (!*name) return 0; - for (i = 0, off = 0; i < kallsyms_num_syms; i++) { - off = kallsyms_expand_symbol(off, namebuf, ARRAY_SIZE(namebuf)); - - if (strcmp(namebuf, name) == 0) - return kallsyms_sym_address(i); + ret = kallsyms_lookup_names(name, &i, NULL); + if (!ret) + return kallsyms_sym_address(get_symbol_seq(i)); - if (cleanup_symbol_name(namebuf) && strcmp(namebuf, name) == 0) - return kallsyms_sym_address(i); - } return module_kallsyms_lookup_name(name); } @@ -233,6 +307,24 @@ int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *, return 0; } +int kallsyms_on_each_match_symbol(int (*fn)(void *, unsigned long), + const char *name, void *data) +{ + int ret; + unsigned int i, start, end; + + ret = kallsyms_lookup_names(name, &start, &end); + if (ret) + return 0; + + for (i = start; !ret && i <= end; i++) { + ret = fn(data, kallsyms_sym_address(get_symbol_seq(i))); + cond_resched(); + } + + return ret; +} + static unsigned long get_symbol_pos(unsigned long addr, unsigned long *symbolsize, unsigned long *offset) diff --git a/kernel/kallsyms_internal.h b/kernel/kallsyms_internal.h index 2d0c6f2f0243..27fabdcc40f5 100644 --- a/kernel/kallsyms_internal.h +++ b/kernel/kallsyms_internal.h @@ -26,5 +26,6 @@ extern const char kallsyms_token_table[] __weak; extern const u16 kallsyms_token_index[] __weak; extern const unsigned int kallsyms_markers[] __weak; +extern const u8 kallsyms_seqs_of_names[] __weak; #endif // LINUX_KALLSYMS_INTERNAL_H_ diff --git a/kernel/kallsyms_selftest.c b/kernel/kallsyms_selftest.c new file mode 100644 index 000000000000..bfbc12da3326 --- /dev/null +++ b/kernel/kallsyms_selftest.c @@ -0,0 +1,476 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Test the function and performance of kallsyms + * + * Copyright (C) Huawei Technologies Co., Ltd., 2022 + * + * Authors: Zhen Lei <thunder.leizhen@huawei.com> Huawei + */ + +#define pr_fmt(fmt) "kallsyms_selftest: " fmt + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/kallsyms.h> +#include <linux/random.h> +#include <linux/sched/clock.h> +#include <linux/kthread.h> +#include <linux/vmalloc.h> + +#include "kallsyms_internal.h" +#include "kallsyms_selftest.h" + + +#define MAX_NUM_OF_RECORDS 64 + +struct test_stat { + int min; + int max; + int save_cnt; + int real_cnt; + int perf; + u64 sum; + char *name; + unsigned long addr; + unsigned long addrs[MAX_NUM_OF_RECORDS]; +}; + +struct test_item { + char *name; + unsigned long addr; +}; + +#define ITEM_FUNC(s) \ + { \ + .name = #s, \ + .addr = (unsigned long)s, \ + } + +#define ITEM_DATA(s) \ + { \ + .name = #s, \ + .addr = (unsigned long)&s, \ + } + + +static int kallsyms_test_var_bss_static; +static int kallsyms_test_var_data_static = 1; +int kallsyms_test_var_bss; +int kallsyms_test_var_data = 1; + +static int kallsyms_test_func_static(void) +{ + kallsyms_test_var_bss_static++; + kallsyms_test_var_data_static++; + + return 0; +} + +int kallsyms_test_func(void) +{ + return kallsyms_test_func_static(); +} + +__weak int kallsyms_test_func_weak(void) +{ + kallsyms_test_var_bss++; + kallsyms_test_var_data++; + return 0; +} + +static struct test_item test_items[] = { + ITEM_FUNC(kallsyms_test_func_static), + ITEM_FUNC(kallsyms_test_func), + ITEM_FUNC(kallsyms_test_func_weak), + ITEM_FUNC(vmalloc), + ITEM_FUNC(vfree), +#ifdef CONFIG_KALLSYMS_ALL + ITEM_DATA(kallsyms_test_var_bss_static), + ITEM_DATA(kallsyms_test_var_data_static), + ITEM_DATA(kallsyms_test_var_bss), + ITEM_DATA(kallsyms_test_var_data), + ITEM_DATA(vmap_area_list), +#endif +}; + +static char stub_name[KSYM_NAME_LEN]; + +static int stat_symbol_len(void *data, const char *name, struct module *mod, unsigned long addr) +{ + *(u32 *)data += strlen(name); + + return 0; +} + +static void test_kallsyms_compression_ratio(void) +{ + u32 pos, off, len, num; + u32 ratio, total_size, total_len = 0; + + kallsyms_on_each_symbol(stat_symbol_len, &total_len); + + /* + * A symbol name cannot start with a number. This stub name helps us + * traverse the entire symbol table without finding a match. It's used + * for subsequent performance tests, and its length is the average + * length of all symbol names. + */ + memset(stub_name, '4', sizeof(stub_name)); + pos = total_len / kallsyms_num_syms; + stub_name[pos] = 0; + + pos = 0; + num = 0; + off = 0; + while (pos < kallsyms_num_syms) { + len = kallsyms_names[off]; + num++; + off++; + pos++; + if ((len & 0x80) != 0) { + len = (len & 0x7f) | (kallsyms_names[off] << 7); + num++; + off++; + } + off += len; + } + + /* + * 1. The length fields is not counted + * 2. The memory occupied by array kallsyms_token_table[] and + * kallsyms_token_index[] needs to be counted. + */ + total_size = off - num; + pos = kallsyms_token_index[0xff]; + total_size += pos + strlen(&kallsyms_token_table[pos]) + 1; + total_size += 0x100 * sizeof(u16); + + pr_info(" ---------------------------------------------------------\n"); + pr_info("| nr_symbols | compressed size | original size | ratio(%%) |\n"); + pr_info("|---------------------------------------------------------|\n"); + ratio = (u32)div_u64(10000ULL * total_size, total_len); + pr_info("| %10d | %10d | %10d | %2d.%-2d |\n", + kallsyms_num_syms, total_size, total_len, ratio / 100, ratio % 100); + pr_info(" ---------------------------------------------------------\n"); +} + +static int lookup_name(void *data, const char *name, struct module *mod, unsigned long addr) +{ + u64 t0, t1, t; + struct test_stat *stat = (struct test_stat *)data; + + t0 = ktime_get_ns(); + (void)kallsyms_lookup_name(name); + t1 = ktime_get_ns(); + + t = t1 - t0; + if (t < stat->min) + stat->min = t; + + if (t > stat->max) + stat->max = t; + + stat->real_cnt++; + stat->sum += t; + + return 0; +} + +static void test_perf_kallsyms_lookup_name(void) +{ + struct test_stat stat; + + memset(&stat, 0, sizeof(stat)); + stat.min = INT_MAX; + kallsyms_on_each_symbol(lookup_name, &stat); + pr_info("kallsyms_lookup_name() looked up %d symbols\n", stat.real_cnt); + pr_info("The time spent on each symbol is (ns): min=%d, max=%d, avg=%lld\n", + stat.min, stat.max, div_u64(stat.sum, stat.real_cnt)); +} + +static bool match_cleanup_name(const char *s, const char *name) +{ + char *p; + int len; + + if (!IS_ENABLED(CONFIG_LTO_CLANG)) + return false; + + p = strchr(s, '.'); + if (!p) + return false; + + len = strlen(name); + if (p - s != len) + return false; + + return !strncmp(s, name, len); +} + +static int find_symbol(void *data, const char *name, struct module *mod, unsigned long addr) +{ + struct test_stat *stat = (struct test_stat *)data; + + if (strcmp(name, stat->name) == 0 || + (!stat->perf && match_cleanup_name(name, stat->name))) { + stat->real_cnt++; + stat->addr = addr; + + if (stat->save_cnt < MAX_NUM_OF_RECORDS) { + stat->addrs[stat->save_cnt] = addr; + stat->save_cnt++; + } + + if (stat->real_cnt == stat->max) + return 1; + } + + return 0; +} + +static void test_perf_kallsyms_on_each_symbol(void) +{ + u64 t0, t1; + struct test_stat stat; + + memset(&stat, 0, sizeof(stat)); + stat.max = INT_MAX; + stat.name = stub_name; + stat.perf = 1; + t0 = ktime_get_ns(); + kallsyms_on_each_symbol(find_symbol, &stat); + t1 = ktime_get_ns(); + pr_info("kallsyms_on_each_symbol() traverse all: %lld ns\n", t1 - t0); +} + +static int match_symbol(void *data, unsigned long addr) +{ + struct test_stat *stat = (struct test_stat *)data; + + stat->real_cnt++; + stat->addr = addr; + + if (stat->save_cnt < MAX_NUM_OF_RECORDS) { + stat->addrs[stat->save_cnt] = addr; + stat->save_cnt++; + } + + if (stat->real_cnt == stat->max) + return 1; + + return 0; +} + +static void test_perf_kallsyms_on_each_match_symbol(void) +{ + u64 t0, t1; + struct test_stat stat; + + memset(&stat, 0, sizeof(stat)); + stat.max = INT_MAX; + stat.name = stub_name; + t0 = ktime_get_ns(); + kallsyms_on_each_match_symbol(match_symbol, stat.name, &stat); + t1 = ktime_get_ns(); + pr_info("kallsyms_on_each_match_symbol() traverse all: %lld ns\n", t1 - t0); +} + +static int test_kallsyms_basic_function(void) +{ + int i, j, ret; + int next = 0, nr_failed = 0; + char *prefix; + unsigned short rand; + unsigned long addr, lookup_addr; + char namebuf[KSYM_NAME_LEN]; + struct test_stat *stat, *stat2; + + stat = kmalloc(sizeof(*stat) * 2, GFP_KERNEL); + if (!stat) + return -ENOMEM; + stat2 = stat + 1; + + prefix = "kallsyms_lookup_name() for"; + for (i = 0; i < ARRAY_SIZE(test_items); i++) { + addr = kallsyms_lookup_name(test_items[i].name); + if (addr != test_items[i].addr) { + nr_failed++; + pr_info("%s %s failed: addr=%lx, expect %lx\n", + prefix, test_items[i].name, addr, test_items[i].addr); + } + } + + prefix = "kallsyms_on_each_symbol() for"; + for (i = 0; i < ARRAY_SIZE(test_items); i++) { + memset(stat, 0, sizeof(*stat)); + stat->max = INT_MAX; + stat->name = test_items[i].name; + kallsyms_on_each_symbol(find_symbol, stat); + if (stat->addr != test_items[i].addr || stat->real_cnt != 1) { + nr_failed++; + pr_info("%s %s failed: count=%d, addr=%lx, expect %lx\n", + prefix, test_items[i].name, + stat->real_cnt, stat->addr, test_items[i].addr); + } + } + + prefix = "kallsyms_on_each_match_symbol() for"; + for (i = 0; i < ARRAY_SIZE(test_items); i++) { + memset(stat, 0, sizeof(*stat)); + stat->max = INT_MAX; + stat->name = test_items[i].name; + kallsyms_on_each_match_symbol(match_symbol, test_items[i].name, stat); + if (stat->addr != test_items[i].addr || stat->real_cnt != 1) { + nr_failed++; + pr_info("%s %s failed: count=%d, addr=%lx, expect %lx\n", + prefix, test_items[i].name, + stat->real_cnt, stat->addr, test_items[i].addr); + } + } + + if (nr_failed) { + kfree(stat); + return -ESRCH; + } + + for (i = 0; i < kallsyms_num_syms; i++) { + addr = kallsyms_sym_address(i); + if (!is_ksym_addr(addr)) + continue; + + ret = lookup_symbol_name(addr, namebuf); + if (unlikely(ret)) { + namebuf[0] = 0; + goto failed; + } + + /* + * The first '.' may be the initial letter, in which case the + * entire symbol name will be truncated to an empty string in + * cleanup_symbol_name(). Do not test these symbols. + * + * For example: + * cat /proc/kallsyms | awk '{print $3}' | grep -E "^\." | head + * .E_read_words + * .E_leading_bytes + * .E_trailing_bytes + * .E_write_words + * .E_copy + * .str.292.llvm.12122243386960820698 + * .str.24.llvm.12122243386960820698 + * .str.29.llvm.12122243386960820698 + * .str.75.llvm.12122243386960820698 + * .str.99.llvm.12122243386960820698 + */ + if (IS_ENABLED(CONFIG_LTO_CLANG) && !namebuf[0]) + continue; + + lookup_addr = kallsyms_lookup_name(namebuf); + + memset(stat, 0, sizeof(*stat)); + stat->max = INT_MAX; + kallsyms_on_each_match_symbol(match_symbol, namebuf, stat); + + /* + * kallsyms_on_each_symbol() is too slow, randomly select some + * symbols for test. + */ + if (i >= next) { + memset(stat2, 0, sizeof(*stat2)); + stat2->max = INT_MAX; + stat2->name = namebuf; + kallsyms_on_each_symbol(find_symbol, stat2); + + /* + * kallsyms_on_each_symbol() and kallsyms_on_each_match_symbol() + * need to get the same traversal result. + */ + if (stat->addr != stat2->addr || + stat->real_cnt != stat2->real_cnt || + memcmp(stat->addrs, stat2->addrs, + stat->save_cnt * sizeof(stat->addrs[0]))) + goto failed; + + /* + * The average of random increments is 128, that is, one of + * them is tested every 128 symbols. + */ + get_random_bytes(&rand, sizeof(rand)); + next = i + (rand & 0xff) + 1; + } + + /* Need to be found at least once */ + if (!stat->real_cnt) + goto failed; + + /* + * kallsyms_lookup_name() returns the address of the first + * symbol found and cannot be NULL. + */ + if (!lookup_addr || lookup_addr != stat->addrs[0]) + goto failed; + + /* + * If the addresses of all matching symbols are recorded, the + * target address needs to be exist. + */ + if (stat->real_cnt <= MAX_NUM_OF_RECORDS) { + for (j = 0; j < stat->save_cnt; j++) { + if (stat->addrs[j] == addr) + break; + } + + if (j == stat->save_cnt) + goto failed; + } + } + + kfree(stat); + + return 0; + +failed: + pr_info("Test for %dth symbol failed: (%s) addr=%lx", i, namebuf, addr); + kfree(stat); + return -ESRCH; +} + +static int test_entry(void *p) +{ + int ret; + + do { + schedule_timeout(5 * HZ); + } while (system_state != SYSTEM_RUNNING); + + pr_info("start\n"); + ret = test_kallsyms_basic_function(); + if (ret) { + pr_info("abort\n"); + return 0; + } + + test_kallsyms_compression_ratio(); + test_perf_kallsyms_lookup_name(); + test_perf_kallsyms_on_each_symbol(); + test_perf_kallsyms_on_each_match_symbol(); + pr_info("finish\n"); + + return 0; +} + +static int __init kallsyms_test_init(void) +{ + struct task_struct *t; + + t = kthread_create(test_entry, NULL, "kallsyms_test"); + if (IS_ERR(t)) { + pr_info("Create kallsyms selftest task failed\n"); + return PTR_ERR(t); + } + kthread_bind(t, 0); + wake_up_process(t); + + return 0; +} +late_initcall(kallsyms_test_init); diff --git a/kernel/kallsyms_selftest.h b/kernel/kallsyms_selftest.h new file mode 100644 index 000000000000..c0ca548e2a22 --- /dev/null +++ b/kernel/kallsyms_selftest.h @@ -0,0 +1,13 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef LINUX_KALLSYMS_SELFTEST_H_ +#define LINUX_KALLSYMS_SELFTEST_H_ + +#include <linux/types.h> + +extern int kallsyms_test_var_bss; +extern int kallsyms_test_var_data; + +extern int kallsyms_test_func(void); +extern int kallsyms_test_func_weak(void); + +#endif // LINUX_KALLSYMS_SELFTEST_H_ diff --git a/kernel/kcsan/kcsan_test.c b/kernel/kcsan/kcsan_test.c index dcec1b743c69..a60c561724be 100644 --- a/kernel/kcsan/kcsan_test.c +++ b/kernel/kcsan/kcsan_test.c @@ -159,7 +159,7 @@ static bool __report_matches(const struct expect_report *r) const bool is_assert = (r->access[0].type | r->access[1].type) & KCSAN_ACCESS_ASSERT; bool ret = false; unsigned long flags; - typeof(observed.lines) expect; + typeof(*observed.lines) *expect; const char *end; char *cur; int i; @@ -168,6 +168,10 @@ static bool __report_matches(const struct expect_report *r) if (!report_available()) return false; + expect = kmalloc(sizeof(observed.lines), GFP_KERNEL); + if (WARN_ON(!expect)) + return false; + /* Generate expected report contents. */ /* Title */ @@ -253,6 +257,7 @@ static bool __report_matches(const struct expect_report *r) strstr(observed.lines[2], expect[1]))); out: spin_unlock_irqrestore(&observed.lock, flags); + kfree(expect); return ret; } diff --git a/kernel/kcsan/report.c b/kernel/kcsan/report.c index 67794404042a..e95ce7d7a76e 100644 --- a/kernel/kcsan/report.c +++ b/kernel/kcsan/report.c @@ -492,8 +492,7 @@ static void print_report(enum kcsan_value_change value_change, dump_stack_print_info(KERN_DEFAULT); pr_err("==================================================================\n"); - if (panic_on_warn) - panic("panic_on_warn set ...\n"); + check_panic_on_warn("KCSAN"); } static void release_report(unsigned long *flags, struct other_info *other_info) diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 3050631e528d..1c18ecf9f98b 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -2213,13 +2213,9 @@ int register_kretprobe(struct kretprobe *rp) rp->kp.post_handler = NULL; /* Pre-allocate memory for max kretprobe instances */ - if (rp->maxactive <= 0) { -#ifdef CONFIG_PREEMPTION + if (rp->maxactive <= 0) rp->maxactive = max_t(unsigned int, 10, 2*num_possible_cpus()); -#else - rp->maxactive = num_possible_cpus(); -#endif - } + #ifdef CONFIG_KRETPROBE_ON_RETHOOK rp->rh = rethook_alloc((void *)rp, kretprobe_rethook_handler); if (!rp->rh) @@ -2364,6 +2360,14 @@ static void kill_kprobe(struct kprobe *p) lockdep_assert_held(&kprobe_mutex); + /* + * The module is going away. We should disarm the kprobe which + * is using ftrace, because ftrace framework is still available at + * 'MODULE_STATE_GOING' notification. + */ + if (kprobe_ftrace(p) && !kprobe_disabled(p) && !kprobes_all_disarmed) + disarm_kprobe_ftrace(p); + p->flags |= KPROBE_FLAG_GONE; if (kprobe_aggrprobe(p)) { /* @@ -2380,14 +2384,6 @@ static void kill_kprobe(struct kprobe *p) * the original probed function (which will be freed soon) any more. */ arch_remove_kprobe(p); - - /* - * The module is going away. We should disarm the kprobe which - * is using ftrace, because ftrace framework is still available at - * 'MODULE_STATE_GOING' notification. - */ - if (kprobe_ftrace(p) && !kprobe_disabled(p) && !kprobes_all_disarmed) - disarm_kprobe_ftrace(p); } /* Disable one kprobe */ diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c index 65dba9076f31..2df00b789b90 100644 --- a/kernel/ksysfs.c +++ b/kernel/ksysfs.c @@ -6,6 +6,7 @@ * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org> */ +#include <asm/byteorder.h> #include <linux/kobject.h> #include <linux/string.h> #include <linux/sysfs.h> @@ -20,6 +21,14 @@ #include <linux/rcupdate.h> /* rcu_expedited and rcu_normal */ +#if defined(__LITTLE_ENDIAN) +#define CPU_BYTEORDER_STRING "little" +#elif defined(__BIG_ENDIAN) +#define CPU_BYTEORDER_STRING "big" +#else +#error Unknown byteorder +#endif + #define KERNEL_ATTR_RO(_name) \ static struct kobj_attribute _name##_attr = __ATTR_RO(_name) @@ -34,6 +43,14 @@ static ssize_t uevent_seqnum_show(struct kobject *kobj, } KERNEL_ATTR_RO(uevent_seqnum); +/* cpu byteorder */ +static ssize_t cpu_byteorder_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sysfs_emit(buf, "%s\n", CPU_BYTEORDER_STRING); +} +KERNEL_ATTR_RO(cpu_byteorder); + #ifdef CONFIG_UEVENT_HELPER /* uevent helper program, used during early boot */ static ssize_t uevent_helper_show(struct kobject *kobj, @@ -215,6 +232,7 @@ EXPORT_SYMBOL_GPL(kernel_kobj); static struct attribute * kernel_attrs[] = { &fscaps_attr.attr, &uevent_seqnum_attr.attr, + &cpu_byteorder_attr.attr, #ifdef CONFIG_UEVENT_HELPER &uevent_helper_attr.attr, #endif diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index 9ada0bc5247b..201f0c0482fb 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -125,20 +125,10 @@ struct klp_find_arg { unsigned long pos; }; -static int klp_find_callback(void *data, const char *name, - struct module *mod, unsigned long addr) +static int klp_match_callback(void *data, unsigned long addr) { struct klp_find_arg *args = data; - if ((mod && !args->objname) || (!mod && args->objname)) - return 0; - - if (strcmp(args->name, name)) - return 0; - - if (args->objname && strcmp(args->objname, mod->name)) - return 0; - args->addr = addr; args->count++; @@ -153,6 +143,23 @@ static int klp_find_callback(void *data, const char *name, return 0; } +static int klp_find_callback(void *data, const char *name, + struct module *mod, unsigned long addr) +{ + struct klp_find_arg *args = data; + + if ((mod && !args->objname) || (!mod && args->objname)) + return 0; + + if (strcmp(args->name, name)) + return 0; + + if (args->objname && strcmp(args->objname, mod->name)) + return 0; + + return klp_match_callback(data, addr); +} + static int klp_find_object_symbol(const char *objname, const char *name, unsigned long sympos, unsigned long *addr) { @@ -167,7 +174,7 @@ static int klp_find_object_symbol(const char *objname, const char *name, if (objname) module_kallsyms_on_each_symbol(klp_find_callback, &args); else - kallsyms_on_each_symbol(klp_find_callback, &args); + kallsyms_on_each_match_symbol(klp_match_callback, name, &args); /* * Ensure an address was found. If sympos is 0, ensure symbol is unique; diff --git a/kernel/locking/Makefile b/kernel/locking/Makefile index ea925731fa40..0db4093d17b8 100644 --- a/kernel/locking/Makefile +++ b/kernel/locking/Makefile @@ -7,7 +7,6 @@ obj-y += mutex.o semaphore.o rwsem.o percpu-rwsem.o # Avoid recursion lockdep -> sanitizer -> ... -> lockdep. KCSAN_SANITIZE_lockdep.o := n -KMSAN_SANITIZE_lockdep.o := n ifdef CONFIG_FUNCTION_TRACER CFLAGS_REMOVE_lockdep.o = $(CC_FLAGS_FTRACE) diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index 7779ee8abc2a..010cf4e6d0b8 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -89,15 +89,31 @@ static inline int __ww_mutex_check_kill(struct rt_mutex *lock, * set this bit before looking at the lock. */ -static __always_inline void -rt_mutex_set_owner(struct rt_mutex_base *lock, struct task_struct *owner) +static __always_inline struct task_struct * +rt_mutex_owner_encode(struct rt_mutex_base *lock, struct task_struct *owner) { unsigned long val = (unsigned long)owner; if (rt_mutex_has_waiters(lock)) val |= RT_MUTEX_HAS_WAITERS; - WRITE_ONCE(lock->owner, (struct task_struct *)val); + return (struct task_struct *)val; +} + +static __always_inline void +rt_mutex_set_owner(struct rt_mutex_base *lock, struct task_struct *owner) +{ + /* + * lock->wait_lock is held but explicit acquire semantics are needed + * for a new lock owner so WRITE_ONCE is insufficient. + */ + xchg_acquire(&lock->owner, rt_mutex_owner_encode(lock, owner)); +} + +static __always_inline void rt_mutex_clear_owner(struct rt_mutex_base *lock) +{ + /* lock->wait_lock is held so the unlock provides release semantics. */ + WRITE_ONCE(lock->owner, rt_mutex_owner_encode(lock, NULL)); } static __always_inline void clear_rt_mutex_waiters(struct rt_mutex_base *lock) @@ -106,7 +122,8 @@ static __always_inline void clear_rt_mutex_waiters(struct rt_mutex_base *lock) ((unsigned long)lock->owner & ~RT_MUTEX_HAS_WAITERS); } -static __always_inline void fixup_rt_mutex_waiters(struct rt_mutex_base *lock) +static __always_inline void +fixup_rt_mutex_waiters(struct rt_mutex_base *lock, bool acquire_lock) { unsigned long owner, *p = (unsigned long *) &lock->owner; @@ -172,8 +189,21 @@ static __always_inline void fixup_rt_mutex_waiters(struct rt_mutex_base *lock) * still set. */ owner = READ_ONCE(*p); - if (owner & RT_MUTEX_HAS_WAITERS) - WRITE_ONCE(*p, owner & ~RT_MUTEX_HAS_WAITERS); + if (owner & RT_MUTEX_HAS_WAITERS) { + /* + * See rt_mutex_set_owner() and rt_mutex_clear_owner() on + * why xchg_acquire() is used for updating owner for + * locking and WRITE_ONCE() for unlocking. + * + * WRITE_ONCE() would work for the acquire case too, but + * in case that the lock acquisition failed it might + * force other lockers into the slow path unnecessarily. + */ + if (acquire_lock) + xchg_acquire(p, owner & ~RT_MUTEX_HAS_WAITERS); + else + WRITE_ONCE(*p, owner & ~RT_MUTEX_HAS_WAITERS); + } } /* @@ -208,6 +238,13 @@ static __always_inline void mark_rt_mutex_waiters(struct rt_mutex_base *lock) owner = *p; } while (cmpxchg_relaxed(p, owner, owner | RT_MUTEX_HAS_WAITERS) != owner); + + /* + * The cmpxchg loop above is relaxed to avoid back-to-back ACQUIRE + * operations in the event of contention. Ensure the successful + * cmpxchg is visible. + */ + smp_mb__after_atomic(); } /* @@ -1243,7 +1280,7 @@ static int __sched __rt_mutex_slowtrylock(struct rt_mutex_base *lock) * try_to_take_rt_mutex() sets the lock waiters bit * unconditionally. Clean this up. */ - fixup_rt_mutex_waiters(lock); + fixup_rt_mutex_waiters(lock, true); return ret; } @@ -1604,7 +1641,7 @@ static int __sched __rt_mutex_slowlock(struct rt_mutex_base *lock, * try_to_take_rt_mutex() sets the waiter bit * unconditionally. We might have to fix that up. */ - fixup_rt_mutex_waiters(lock); + fixup_rt_mutex_waiters(lock, true); trace_contention_end(lock, ret); @@ -1719,7 +1756,7 @@ static void __sched rtlock_slowlock_locked(struct rt_mutex_base *lock) * try_to_take_rt_mutex() sets the waiter bit unconditionally. * We might have to fix that up: */ - fixup_rt_mutex_waiters(lock); + fixup_rt_mutex_waiters(lock, true); debug_rt_mutex_free_waiter(&waiter); trace_contention_end(lock, 0); diff --git a/kernel/locking/rtmutex_api.c b/kernel/locking/rtmutex_api.c index 900220941caa..cb9fdff76a8a 100644 --- a/kernel/locking/rtmutex_api.c +++ b/kernel/locking/rtmutex_api.c @@ -267,7 +267,7 @@ void __sched rt_mutex_init_proxy_locked(struct rt_mutex_base *lock, void __sched rt_mutex_proxy_unlock(struct rt_mutex_base *lock) { debug_rt_mutex_proxy_unlock(lock); - rt_mutex_set_owner(lock, NULL); + rt_mutex_clear_owner(lock); } /** @@ -382,7 +382,7 @@ int __sched rt_mutex_wait_proxy_lock(struct rt_mutex_base *lock, * try_to_take_rt_mutex() sets the waiter bit unconditionally. We might * have to fix that up. */ - fixup_rt_mutex_waiters(lock); + fixup_rt_mutex_waiters(lock, true); raw_spin_unlock_irq(&lock->wait_lock); return ret; @@ -438,7 +438,7 @@ bool __sched rt_mutex_cleanup_proxy_lock(struct rt_mutex_base *lock, * try_to_take_rt_mutex() sets the waiter bit unconditionally. We might * have to fix that up. */ - fixup_rt_mutex_waiters(lock); + fixup_rt_mutex_waiters(lock, false); raw_spin_unlock_irq(&lock->wait_lock); diff --git a/kernel/module/Kconfig b/kernel/module/Kconfig index 26ea5d04f56c..424b3bc58f3f 100644 --- a/kernel/module/Kconfig +++ b/kernel/module/Kconfig @@ -221,9 +221,10 @@ endchoice config MODULE_DECOMPRESS bool "Support in-kernel module decompression" - depends on MODULE_COMPRESS_GZIP || MODULE_COMPRESS_XZ + depends on MODULE_COMPRESS_GZIP || MODULE_COMPRESS_XZ || MODULE_COMPRESS_ZSTD select ZLIB_INFLATE if MODULE_COMPRESS_GZIP select XZ_DEC if MODULE_COMPRESS_XZ + select ZSTD_DECOMPRESS if MODULE_COMPRESS_ZSTD help Support for decompressing kernel modules by the kernel itself diff --git a/kernel/module/decompress.c b/kernel/module/decompress.c index c033572d83f0..bb79ac1a6d8f 100644 --- a/kernel/module/decompress.c +++ b/kernel/module/decompress.c @@ -50,7 +50,7 @@ static struct page *module_get_next_page(struct load_info *info) return page; } -#ifdef CONFIG_MODULE_COMPRESS_GZIP +#if defined(CONFIG_MODULE_COMPRESS_GZIP) #include <linux/zlib.h> #define MODULE_COMPRESSION gzip #define MODULE_DECOMPRESS_FN module_gzip_decompress @@ -114,8 +114,8 @@ static ssize_t module_gzip_decompress(struct load_info *info, do { struct page *page = module_get_next_page(info); - if (!page) { - retval = -ENOMEM; + if (IS_ERR(page)) { + retval = PTR_ERR(page); goto out_inflate_end; } @@ -141,7 +141,7 @@ out: kfree(s.workspace); return retval; } -#elif CONFIG_MODULE_COMPRESS_XZ +#elif defined(CONFIG_MODULE_COMPRESS_XZ) #include <linux/xz.h> #define MODULE_COMPRESSION xz #define MODULE_DECOMPRESS_FN module_xz_decompress @@ -173,8 +173,8 @@ static ssize_t module_xz_decompress(struct load_info *info, do { struct page *page = module_get_next_page(info); - if (!page) { - retval = -ENOMEM; + if (IS_ERR(page)) { + retval = PTR_ERR(page); goto out; } @@ -199,6 +199,94 @@ static ssize_t module_xz_decompress(struct load_info *info, xz_dec_end(xz_dec); return retval; } +#elif defined(CONFIG_MODULE_COMPRESS_ZSTD) +#include <linux/zstd.h> +#define MODULE_COMPRESSION zstd +#define MODULE_DECOMPRESS_FN module_zstd_decompress + +static ssize_t module_zstd_decompress(struct load_info *info, + const void *buf, size_t size) +{ + static const u8 signature[] = { 0x28, 0xb5, 0x2f, 0xfd }; + ZSTD_outBuffer zstd_dec; + ZSTD_inBuffer zstd_buf; + zstd_frame_header header; + size_t wksp_size; + void *wksp = NULL; + ZSTD_DStream *dstream; + size_t ret; + size_t new_size = 0; + int retval; + + if (size < sizeof(signature) || + memcmp(buf, signature, sizeof(signature))) { + pr_err("not a zstd compressed module\n"); + return -EINVAL; + } + + zstd_buf.src = buf; + zstd_buf.pos = 0; + zstd_buf.size = size; + + ret = zstd_get_frame_header(&header, zstd_buf.src, zstd_buf.size); + if (ret != 0) { + pr_err("ZSTD-compressed data has an incomplete frame header\n"); + retval = -EINVAL; + goto out; + } + if (header.windowSize > (1 << ZSTD_WINDOWLOG_MAX)) { + pr_err("ZSTD-compressed data has too large a window size\n"); + retval = -EINVAL; + goto out; + } + + wksp_size = zstd_dstream_workspace_bound(header.windowSize); + wksp = kmalloc(wksp_size, GFP_KERNEL); + if (!wksp) { + retval = -ENOMEM; + goto out; + } + + dstream = zstd_init_dstream(header.windowSize, wksp, wksp_size); + if (!dstream) { + pr_err("Can't initialize ZSTD stream\n"); + retval = -ENOMEM; + goto out; + } + + do { + struct page *page = module_get_next_page(info); + + if (!IS_ERR(page)) { + retval = PTR_ERR(page); + goto out; + } + + zstd_dec.dst = kmap_local_page(page); + zstd_dec.pos = 0; + zstd_dec.size = PAGE_SIZE; + + ret = zstd_decompress_stream(dstream, &zstd_dec, &zstd_buf); + kunmap(page); + retval = zstd_get_error_code(ret); + if (retval) + break; + + new_size += zstd_dec.pos; + } while (zstd_dec.pos == PAGE_SIZE && ret != 0); + + if (retval) { + pr_err("ZSTD-decompression failed with status %d\n", retval); + retval = -EINVAL; + goto out; + } + + retval = new_size; + + out: + kfree(wksp); + return retval; +} #else #error "Unexpected configuration for CONFIG_MODULE_DECOMPRESS" #endif diff --git a/kernel/module/kallsyms.c b/kernel/module/kallsyms.c index f5c5c9175333..4523f99b0358 100644 --- a/kernel/module/kallsyms.c +++ b/kernel/module/kallsyms.c @@ -494,7 +494,6 @@ unsigned long module_kallsyms_lookup_name(const char *name) return ret; } -#ifdef CONFIG_LIVEPATCH int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *, unsigned long), void *data) @@ -531,4 +530,3 @@ out: mutex_unlock(&module_mutex); return ret; } -#endif /* CONFIG_LIVEPATCH */ diff --git a/kernel/module/main.c b/kernel/module/main.c index d02d39c7174e..4ac3fe43e6c8 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -85,9 +85,6 @@ struct mod_tree_root mod_data_tree __cacheline_aligned = { }; #endif -#define module_addr_min mod_tree.addr_min -#define module_addr_max mod_tree.addr_max - struct symsearch { const struct kernel_symbol *start, *stop; const s32 *crcs; @@ -1674,6 +1671,11 @@ static int elf_validity_check(struct load_info *info) info->hdr->e_machine); goto no_exec; } + if (!module_elf_check_arch(info->hdr)) { + pr_err("Invalid module architecture in ELF header: %u\n", + info->hdr->e_machine); + goto no_exec; + } if (info->hdr->e_shentsize != sizeof(Elf_Shdr)) { pr_err("Invalid ELF section header size\n"); goto no_exec; @@ -2247,6 +2249,11 @@ static void flush_module_icache(const struct module *mod) (unsigned long)mod->core_layout.base + mod->core_layout.size); } +bool __weak module_elf_check_arch(Elf_Ehdr *hdr) +{ + return true; +} + int __weak module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, char *secstrings, @@ -2386,7 +2393,8 @@ static bool finished_loading(const char *name) sched_annotate_sleep(); mutex_lock(&module_mutex); mod = find_module_all(name, strlen(name), true); - ret = !mod || mod->state == MODULE_STATE_LIVE; + ret = !mod || mod->state == MODULE_STATE_LIVE + || mod->state == MODULE_STATE_GOING; mutex_unlock(&module_mutex); return ret; @@ -2562,20 +2570,35 @@ static int add_unformed_module(struct module *mod) mod->state = MODULE_STATE_UNFORMED; -again: mutex_lock(&module_mutex); old = find_module_all(mod->name, strlen(mod->name), true); if (old != NULL) { - if (old->state != MODULE_STATE_LIVE) { + if (old->state == MODULE_STATE_COMING + || old->state == MODULE_STATE_UNFORMED) { /* Wait in case it fails to load. */ mutex_unlock(&module_mutex); err = wait_event_interruptible(module_wq, finished_loading(mod->name)); if (err) goto out_unlocked; - goto again; + + /* The module might have gone in the meantime. */ + mutex_lock(&module_mutex); + old = find_module_all(mod->name, strlen(mod->name), + true); } - err = -EEXIST; + + /* + * We are here only when the same module was being loaded. Do + * not try to load it again right now. It prevents long delays + * caused by serialized module load failures. It might happen + * when more devices of the same type trigger load of + * a particular module. + */ + if (old && old->state == MODULE_STATE_LIVE) + err = -EEXIST; + else + err = -EBUSY; goto out; } mod_update_bounds(mod); diff --git a/kernel/module/sysfs.c b/kernel/module/sysfs.c index ce68f821dcd1..c921bf044050 100644 --- a/kernel/module/sysfs.c +++ b/kernel/module/sysfs.c @@ -340,7 +340,7 @@ static int mod_sysfs_init(struct module *mod) int err; struct kobject *kobj; - if (!module_sysfs_initialized) { + if (!module_kset) { pr_err("%s: module sysfs not initialized\n", mod->name); err = -EINVAL; goto out; diff --git a/kernel/padata.c b/kernel/padata.c index e5819bb8bd1d..e007b8a4b738 100644 --- a/kernel/padata.c +++ b/kernel/padata.c @@ -83,8 +83,16 @@ static struct padata_work *padata_work_alloc(void) return pw; } -static void padata_work_init(struct padata_work *pw, work_func_t work_fn, - void *data, int flags) +/* + * This function is marked __ref because this function may be optimized in such + * a way that it directly refers to work_fn's address, which causes modpost to + * complain when work_fn is marked __init. This scenario was observed with clang + * LTO, where padata_work_init() was optimized to refer directly to + * padata_mt_helper() because the calls to padata_work_init() with other work_fn + * values were eliminated or inlined. + */ +static void __ref padata_work_init(struct padata_work *pw, work_func_t work_fn, + void *data, int flags) { if (flags & PADATA_WORK_ONSTACK) INIT_WORK_ONSTACK(&pw->pw_work, work_fn); @@ -207,14 +215,16 @@ int padata_do_parallel(struct padata_shell *ps, pw = padata_work_alloc(); spin_unlock(&padata_works_lock); + if (!pw) { + /* Maximum works limit exceeded, run in the current task. */ + padata->parallel(padata); + } + rcu_read_unlock_bh(); if (pw) { padata_work_init(pw, padata_parallel_worker, padata, 0); queue_work(pinst->parallel_wq, &pw->pw_work); - } else { - /* Maximum works limit exceeded, run in the current task. */ - padata->parallel(padata); } return 0; @@ -388,13 +398,16 @@ void padata_do_serial(struct padata_priv *padata) int hashed_cpu = padata_cpu_hash(pd, padata->seq_nr); struct padata_list *reorder = per_cpu_ptr(pd->reorder_list, hashed_cpu); struct padata_priv *cur; + struct list_head *pos; spin_lock(&reorder->lock); /* Sort in ascending order of sequence number. */ - list_for_each_entry_reverse(cur, &reorder->list, list) + list_for_each_prev(pos, &reorder->list) { + cur = list_entry(pos, struct padata_priv, list); if (cur->seq_nr < padata->seq_nr) break; - list_add(&padata->list, &cur->list); + } + list_add(&padata->list, pos); spin_unlock(&reorder->lock); /* diff --git a/kernel/panic.c b/kernel/panic.c index 75fe389e8814..463c9295bc28 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -33,6 +33,7 @@ #include <linux/bug.h> #include <linux/ratelimit.h> #include <linux/debugfs.h> +#include <linux/sysfs.h> #include <trace/events/error_report.h> #include <asm/sections.h> @@ -59,6 +60,7 @@ bool crash_kexec_post_notifiers; int panic_on_warn __read_mostly; unsigned long panic_on_taint; bool panic_on_taint_nousertaint = false; +static unsigned int warn_limit __read_mostly; int panic_timeout = CONFIG_PANIC_TIMEOUT; EXPORT_SYMBOL_GPL(panic_timeout); @@ -76,8 +78,9 @@ ATOMIC_NOTIFIER_HEAD(panic_notifier_list); EXPORT_SYMBOL(panic_notifier_list); -#if defined(CONFIG_SMP) && defined(CONFIG_SYSCTL) +#ifdef CONFIG_SYSCTL static struct ctl_table kern_panic_table[] = { +#ifdef CONFIG_SMP { .procname = "oops_all_cpu_backtrace", .data = &sysctl_oops_all_cpu_backtrace, @@ -87,6 +90,14 @@ static struct ctl_table kern_panic_table[] = { .extra1 = SYSCTL_ZERO, .extra2 = SYSCTL_ONE, }, +#endif + { + .procname = "warn_limit", + .data = &warn_limit, + .maxlen = sizeof(warn_limit), + .mode = 0644, + .proc_handler = proc_douintvec, + }, { } }; @@ -98,6 +109,25 @@ static __init int kernel_panic_sysctls_init(void) late_initcall(kernel_panic_sysctls_init); #endif +static atomic_t warn_count = ATOMIC_INIT(0); + +#ifdef CONFIG_SYSFS +static ssize_t warn_count_show(struct kobject *kobj, struct kobj_attribute *attr, + char *page) +{ + return sysfs_emit(page, "%d\n", atomic_read(&warn_count)); +} + +static struct kobj_attribute warn_count_attr = __ATTR_RO(warn_count); + +static __init int kernel_panic_sysfs_init(void) +{ + sysfs_add_file_to_group(kernel_kobj, &warn_count_attr.attr, NULL); + return 0; +} +late_initcall(kernel_panic_sysfs_init); +#endif + static long no_blink(int state) { return 0; @@ -200,6 +230,19 @@ static void panic_print_sys_info(bool console_flush) ftrace_dump(DUMP_ALL); } +void check_panic_on_warn(const char *origin) +{ + unsigned int limit; + + if (panic_on_warn) + panic("%s: panic_on_warn set ...\n", origin); + + limit = READ_ONCE(warn_limit); + if (atomic_inc_return(&warn_count) >= limit && limit) + panic("%s: system warned too often (kernel.warn_limit is %d)", + origin, limit); +} + /** * panic - halt the system * @fmt: The text string to print @@ -618,8 +661,7 @@ void __warn(const char *file, int line, void *caller, unsigned taint, if (regs) show_regs(regs); - if (panic_on_warn) - panic("panic_on_warn set ...\n"); + check_panic_on_warn("kernel"); if (!regs) dump_stack(); diff --git a/kernel/params.c b/kernel/params.c index 5b92310425c5..14d66070757b 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -926,7 +926,7 @@ static const struct sysfs_ops module_sysfs_ops = { .store = module_attr_store, }; -static int uevent_filter(struct kobject *kobj) +static int uevent_filter(const struct kobject *kobj) { const struct kobj_type *ktype = get_ktype(kobj); @@ -940,7 +940,6 @@ static const struct kset_uevent_ops module_uevent_ops = { }; struct kset *module_kset; -int module_sysfs_initialized; static void module_kobj_release(struct kobject *kobj) { @@ -954,7 +953,11 @@ struct kobj_type module_ktype = { }; /* - * param_sysfs_init - wrapper for built-in params support + * param_sysfs_init - create "module" kset + * + * This must be done before the initramfs is unpacked and + * request_module() thus becomes possible, because otherwise the + * module load would fail in mod_sysfs_init. */ static int __init param_sysfs_init(void) { @@ -964,13 +967,25 @@ static int __init param_sysfs_init(void) __FILE__, __LINE__); return -ENOMEM; } - module_sysfs_initialized = 1; + + return 0; +} +subsys_initcall(param_sysfs_init); + +/* + * param_sysfs_builtin_init - add sysfs version and parameter + * attributes for built-in modules + */ +static int __init param_sysfs_builtin_init(void) +{ + if (!module_kset) + return -ENOMEM; version_sysfs_builtin(); param_sysfs_builtin(); return 0; } -subsys_initcall(param_sysfs_init); +late_initcall(param_sysfs_builtin_init); #endif /* CONFIG_SYSFS */ diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 7decf1e9c486..a5ed2e53547c 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -123,6 +123,7 @@ bool console_srcu_read_lock_is_held(void) { return srcu_read_lock_held(&console_srcu); } +EXPORT_SYMBOL(console_srcu_read_lock_is_held); #endif enum devkmsg_log_bits { @@ -1891,6 +1892,7 @@ static void console_lock_spinning_enable(void) /** * console_lock_spinning_disable_and_check - mark end of code where another * thread was able to busy wait and check if there is a waiter + * @cookie: cookie returned from console_srcu_read_lock() * * This is called at the end of the section where spinning is allowed. * It has two functions. First, it is a signal that it is no longer diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h index b0b885e071fa..fe9840d90e96 100644 --- a/kernel/rcu/tasks.h +++ b/kernel/rcu/tasks.h @@ -1535,6 +1535,8 @@ static void rcu_tasks_trace_postscan(struct list_head *hop) { // Wait for late-stage exiting tasks to finish exiting. // These might have passed the call to exit_tasks_rcu_finish(). + + // If you remove the following line, update rcu_trace_implies_rcu_gp()!!! synchronize_rcu(); // Any tasks that exit after this point will set // TRC_NEED_QS_CHECKED in ->trc_reader_special.b.need_qs. diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index d04f2192f02c..cf34a961821a 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -1362,7 +1362,7 @@ static void rcu_poll_gp_seq_start(unsigned long *snap) { struct rcu_node *rnp = rcu_get_root(); - if (rcu_init_invoked()) + if (rcu_scheduler_active != RCU_SCHEDULER_INACTIVE) raw_lockdep_assert_held_rcu_node(rnp); // If RCU was idle, note beginning of GP. @@ -1378,7 +1378,7 @@ static void rcu_poll_gp_seq_end(unsigned long *snap) { struct rcu_node *rnp = rcu_get_root(); - if (rcu_init_invoked()) + if (rcu_scheduler_active != RCU_SCHEDULER_INACTIVE) raw_lockdep_assert_held_rcu_node(rnp); // If the previously noted GP is still in effect, record the @@ -1401,7 +1401,8 @@ static void rcu_poll_gp_seq_start_unlocked(unsigned long *snap) struct rcu_node *rnp = rcu_get_root(); if (rcu_init_invoked()) { - lockdep_assert_irqs_enabled(); + if (rcu_scheduler_active != RCU_SCHEDULER_INACTIVE) + lockdep_assert_irqs_enabled(); raw_spin_lock_irqsave_rcu_node(rnp, flags); } rcu_poll_gp_seq_start(snap); @@ -1417,7 +1418,8 @@ static void rcu_poll_gp_seq_end_unlocked(unsigned long *snap) struct rcu_node *rnp = rcu_get_root(); if (rcu_init_invoked()) { - lockdep_assert_irqs_enabled(); + if (rcu_scheduler_active != RCU_SCHEDULER_INACTIVE) + lockdep_assert_irqs_enabled(); raw_spin_lock_irqsave_rcu_node(rnp, flags); } rcu_poll_gp_seq_end(snap); diff --git a/kernel/resource.c b/kernel/resource.c index 82ed54cd1f0d..ddbbacb9fb50 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -888,7 +888,7 @@ void insert_resource_expand_to_fit(struct resource *root, struct resource *new) if (conflict->end > new->end) new->end = conflict->end; - printk("Expanded resource %s due to conflict with %s\n", new->name, conflict->name); + pr_info("Expanded resource %s due to conflict with %s\n", new->name, conflict->name); } write_unlock(&resource_lock); } @@ -1283,9 +1283,7 @@ void __release_region(struct resource *parent, resource_size_t start, write_unlock(&resource_lock); - printk(KERN_WARNING "Trying to free nonexistent resource " - "<%016llx-%016llx>\n", (unsigned long long)start, - (unsigned long long)end); + pr_warn("Trying to free nonexistent resource <%pa-%pa>\n", &start, &end); } EXPORT_SYMBOL(__release_region); @@ -1658,6 +1656,7 @@ __setup("reserve=", reserve_setup); int iomem_map_sanity_check(resource_size_t addr, unsigned long size) { struct resource *p = &iomem_resource; + resource_size_t end = addr + size - 1; int err = 0; loff_t l; @@ -1667,12 +1666,12 @@ int iomem_map_sanity_check(resource_size_t addr, unsigned long size) * We can probably skip the resources without * IORESOURCE_IO attribute? */ - if (p->start >= addr + size) + if (p->start > end) continue; if (p->end < addr) continue; if (PFN_DOWN(p->start) <= PFN_DOWN(addr) && - PFN_DOWN(p->end) >= PFN_DOWN(addr + size - 1)) + PFN_DOWN(p->end) >= PFN_DOWN(end)) continue; /* * if a resource is "BUSY", it's not a hardware resource @@ -1683,10 +1682,8 @@ int iomem_map_sanity_check(resource_size_t addr, unsigned long size) if (p->flags & IORESOURCE_BUSY) continue; - printk(KERN_WARNING "resource sanity check: requesting [mem %#010llx-%#010llx], which spans more than %s %pR\n", - (unsigned long long)addr, - (unsigned long long)(addr + size - 1), - p->name, p); + pr_warn("resource sanity check: requesting [mem %pa-%pa], which spans more than %s %pR\n", + &addr, &end, p->name, p); err = -1; break; } diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 78b2d5cabcc5..e838feb6adc5 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2604,27 +2604,71 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) .user_mask = NULL, .flags = SCA_USER, /* clear the user requested mask */ }; + union cpumask_rcuhead { + cpumask_t cpumask; + struct rcu_head rcu; + }; __do_set_cpus_allowed(p, &ac); - kfree(ac.user_mask); + + /* + * Because this is called with p->pi_lock held, it is not possible + * to use kfree() here (when PREEMPT_RT=y), therefore punt to using + * kfree_rcu(). + */ + kfree_rcu((union cpumask_rcuhead *)ac.user_mask, rcu); +} + +static cpumask_t *alloc_user_cpus_ptr(int node) +{ + /* + * See do_set_cpus_allowed() above for the rcu_head usage. + */ + int size = max_t(int, cpumask_size(), sizeof(struct rcu_head)); + + return kmalloc_node(size, GFP_KERNEL, node); } int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node) { + cpumask_t *user_mask; unsigned long flags; - if (!src->user_cpus_ptr) + /* + * Always clear dst->user_cpus_ptr first as their user_cpus_ptr's + * may differ by now due to racing. + */ + dst->user_cpus_ptr = NULL; + + /* + * This check is racy and losing the race is a valid situation. + * It is not worth the extra overhead of taking the pi_lock on + * every fork/clone. + */ + if (data_race(!src->user_cpus_ptr)) return 0; - dst->user_cpus_ptr = kmalloc_node(cpumask_size(), GFP_KERNEL, node); - if (!dst->user_cpus_ptr) + user_mask = alloc_user_cpus_ptr(node); + if (!user_mask) return -ENOMEM; - /* Use pi_lock to protect content of user_cpus_ptr */ + /* + * Use pi_lock to protect content of user_cpus_ptr + * + * Though unlikely, user_cpus_ptr can be reset to NULL by a concurrent + * do_set_cpus_allowed(). + */ raw_spin_lock_irqsave(&src->pi_lock, flags); - cpumask_copy(dst->user_cpus_ptr, src->user_cpus_ptr); + if (src->user_cpus_ptr) { + swap(dst->user_cpus_ptr, user_mask); + cpumask_copy(dst->user_cpus_ptr, src->user_cpus_ptr); + } raw_spin_unlock_irqrestore(&src->pi_lock, flags); + + if (unlikely(user_mask)) + kfree(user_mask); + return 0; } @@ -3581,6 +3625,11 @@ static inline bool rq_has_pinned_tasks(struct rq *rq) return false; } +static inline cpumask_t *alloc_user_cpus_ptr(int node) +{ + return NULL; +} + #endif /* !CONFIG_SMP */ static void @@ -4443,7 +4492,7 @@ static void reset_memory_tiering(void) } } -int sysctl_numa_balancing(struct ctl_table *table, int write, +static int sysctl_numa_balancing(struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) { struct ctl_table t; @@ -4570,6 +4619,17 @@ static struct ctl_table sched_core_sysctls[] = { .proc_handler = sysctl_sched_uclamp_handler, }, #endif /* CONFIG_UCLAMP_TASK */ +#ifdef CONFIG_NUMA_BALANCING + { + .procname = "numa_balancing", + .data = NULL, /* filled in by handler */ + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = sysctl_numa_balancing, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_FOUR, + }, +#endif /* CONFIG_NUMA_BALANCING */ {} }; static int __init sched_core_sysctl_init(void) @@ -5493,7 +5553,9 @@ void scheduler_tick(void) unsigned long thermal_pressure; u64 resched_latency; - arch_scale_freq_tick(); + if (housekeeping_cpu(cpu, HK_TYPE_TICK)) + arch_scale_freq_tick(); + sched_clock_tick(); rq_lock(rq, &rf); @@ -5771,8 +5833,7 @@ static noinline void __schedule_bug(struct task_struct *prev) pr_err("Preemption disabled at:"); print_ip_sym(KERN_ERR, preempt_disable_ip); } - if (panic_on_warn) - panic("scheduling while atomic\n"); + check_panic_on_warn("scheduling while atomic"); dump_stack(); add_taint(TAINT_WARN, LOCKDEP_STILL_OK); @@ -8229,12 +8290,18 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask) if (retval) goto out_put_task; - user_mask = kmalloc(cpumask_size(), GFP_KERNEL); - if (!user_mask) { + /* + * With non-SMP configs, user_cpus_ptr/user_mask isn't used and + * alloc_user_cpus_ptr() returns NULL. + */ + user_mask = alloc_user_cpus_ptr(NUMA_NO_NODE); + if (user_mask) { + cpumask_copy(user_mask, in_mask); + } else if (IS_ENABLED(CONFIG_SMP)) { retval = -ENOMEM; goto out_put_task; } - cpumask_copy(user_mask, in_mask); + ac = (struct affinity_context){ .new_mask = in_mask, .user_mask = user_mask, diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 0cd1d0f7c1bd..0f8736991427 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -178,6 +178,11 @@ int __weak arch_asym_cpu_priority(int cpu) static unsigned int sysctl_sched_cfs_bandwidth_slice = 5000UL; #endif +#ifdef CONFIG_NUMA_BALANCING +/* Restrict the NUMA promotion throughput (MB/s) for each target node. */ +static unsigned int sysctl_numa_balancing_promote_rate_limit = 65536; +#endif + #ifdef CONFIG_SYSCTL static struct ctl_table sched_fair_sysctls[] = { { @@ -197,6 +202,16 @@ static struct ctl_table sched_fair_sysctls[] = { .extra1 = SYSCTL_ONE, }, #endif +#ifdef CONFIG_NUMA_BALANCING + { + .procname = "numa_balancing_promote_rate_limit_MBps", + .data = &sysctl_numa_balancing_promote_rate_limit, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + }, +#endif /* CONFIG_NUMA_BALANCING */ {} }; @@ -1094,9 +1109,6 @@ unsigned int sysctl_numa_balancing_scan_delay = 1000; /* The page with hint page fault latency < threshold in ms is considered hot */ unsigned int sysctl_numa_balancing_hot_threshold = MSEC_PER_SEC; -/* Restrict the NUMA promotion throughput (MB/s) for each target node. */ -unsigned int sysctl_numa_balancing_promote_rate_limit = 65536; - struct numa_group { refcount_t refcount; @@ -7217,10 +7229,10 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu) eenv_task_busy_time(&eenv, p, prev_cpu); for (; pd; pd = pd->next) { + unsigned long util_min = p_util_min, util_max = p_util_max; unsigned long cpu_cap, cpu_thermal_cap, util; unsigned long cur_delta, max_spare_cap = 0; unsigned long rq_util_min, rq_util_max; - unsigned long util_min, util_max; unsigned long prev_spare_cap = 0; int max_spare_cap_cpu = -1; unsigned long base_energy; @@ -7239,6 +7251,8 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu) eenv.pd_cap = 0; for_each_cpu(cpu, cpus) { + struct rq *rq = cpu_rq(cpu); + eenv.pd_cap += cpu_thermal_cap; if (!cpumask_test_cpu(cpu, sched_domain_span(sd))) @@ -7257,24 +7271,19 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu) * much capacity we can get out of the CPU; this is * aligned with sched_cpu_util(). */ - if (uclamp_is_used()) { - if (uclamp_rq_is_idle(cpu_rq(cpu))) { - util_min = p_util_min; - util_max = p_util_max; - } else { - /* - * Open code uclamp_rq_util_with() except for - * the clamp() part. Ie: apply max aggregation - * only. util_fits_cpu() logic requires to - * operate on non clamped util but must use the - * max-aggregated uclamp_{min, max}. - */ - rq_util_min = uclamp_rq_get(cpu_rq(cpu), UCLAMP_MIN); - rq_util_max = uclamp_rq_get(cpu_rq(cpu), UCLAMP_MAX); - - util_min = max(rq_util_min, p_util_min); - util_max = max(rq_util_max, p_util_max); - } + if (uclamp_is_used() && !uclamp_rq_is_idle(rq)) { + /* + * Open code uclamp_rq_util_with() except for + * the clamp() part. Ie: apply max aggregation + * only. util_fits_cpu() logic requires to + * operate on non clamped util but must use the + * max-aggregated uclamp_{min, max}. + */ + rq_util_min = uclamp_rq_get(rq, UCLAMP_MIN); + rq_util_max = uclamp_rq_get(rq, UCLAMP_MAX); + + util_min = max(rq_util_min, p_util_min); + util_max = max(rq_util_max, p_util_max); } if (!util_fits_cpu(util, util_min, util_max, cpu)) continue; @@ -8859,16 +8868,23 @@ static void update_cpu_capacity(struct sched_domain *sd, int cpu) * * Thermal pressure will impact all cpus in this perf domain * equally. */ - if (static_branch_unlikely(&sched_asym_cpucapacity)) { + if (sched_energy_enabled()) { unsigned long inv_cap = capacity_orig - thermal_load_avg(rq); - struct perf_domain *pd = rcu_dereference(rq->rd->pd); + struct perf_domain *pd; + rcu_read_lock(); + + pd = rcu_dereference(rq->rd->pd); rq->cpu_capacity_inverted = 0; for (; pd; pd = pd->next) { struct cpumask *pd_span = perf_domain_span(pd); unsigned long pd_cap_orig, pd_cap; + /* We can't be inverted against our own pd */ + if (cpumask_test_cpu(cpu_of(rq), pd_span)) + continue; + cpu = cpumask_any(pd_span); pd_cap_orig = arch_scale_cpu_capacity(cpu); @@ -8893,6 +8909,8 @@ static void update_cpu_capacity(struct sched_domain *sd, int cpu) break; } } + + rcu_read_unlock(); } trace_sched_cpu_capacity_tp(rq); diff --git a/kernel/signal.c b/kernel/signal.c index 848d5c282d35..ae26da61c4d9 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2693,6 +2693,7 @@ relock: /* Has this task already been marked for death? */ if ((signal->flags & SIGNAL_GROUP_EXIT) || signal->group_exec_task) { + clear_siginfo(&ksig->info); ksig->info.si_signo = signr = SIGKILL; sigdelset(¤t->pending.signal, SIGKILL); trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, diff --git a/kernel/static_call_inline.c b/kernel/static_call_inline.c index dc5665b62814..639397b5491c 100644 --- a/kernel/static_call_inline.c +++ b/kernel/static_call_inline.c @@ -15,7 +15,18 @@ extern struct static_call_site __start_static_call_sites[], extern struct static_call_tramp_key __start_static_call_tramp_key[], __stop_static_call_tramp_key[]; -static bool static_call_initialized; +static int static_call_initialized; + +/* + * Must be called before early_initcall() to be effective. + */ +void static_call_force_reinit(void) +{ + if (WARN_ON_ONCE(!static_call_initialized)) + return; + + static_call_initialized++; +} /* mutex to protect key modules/sites */ static DEFINE_MUTEX(static_call_mutex); @@ -475,7 +486,8 @@ int __init static_call_init(void) { int ret; - if (static_call_initialized) + /* See static_call_force_reinit(). */ + if (static_call_initialized == 1) return 0; cpus_read_lock(); @@ -490,11 +502,12 @@ int __init static_call_init(void) BUG(); } - static_call_initialized = true; - #ifdef CONFIG_MODULES - register_module_notifier(&static_call_module_nb); + if (!static_call_initialized) + register_module_notifier(&static_call_module_nb); #endif + + static_call_initialized = 1; return 0; } early_initcall(static_call_init); diff --git a/kernel/sys.c b/kernel/sys.c index 5fd54bf0e886..88b31f096fb2 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1442,6 +1442,8 @@ static int do_prlimit(struct task_struct *tsk, unsigned int resource, if (resource >= RLIM_NLIMITS) return -EINVAL; + resource = array_index_nospec(resource, RLIM_NLIMITS); + if (new_rlim) { if (new_rlim->rlim_cur > new_rlim->rlim_max) return -EINVAL; diff --git a/kernel/sysctl.c b/kernel/sysctl.c index c6d9dec11b74..137d4abe3eda 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -1633,25 +1633,6 @@ int proc_do_static_key(struct ctl_table *table, int write, } static struct ctl_table kern_table[] = { -#ifdef CONFIG_NUMA_BALANCING - { - .procname = "numa_balancing", - .data = NULL, /* filled in by handler */ - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = sysctl_numa_balancing, - .extra1 = SYSCTL_ZERO, - .extra2 = SYSCTL_FOUR, - }, - { - .procname = "numa_balancing_promote_rate_limit_MBps", - .data = &sysctl_numa_balancing_promote_rate_limit, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = SYSCTL_ZERO, - }, -#endif /* CONFIG_NUMA_BALANCING */ { .procname = "panic", .data = &panic_timeout, @@ -2125,6 +2106,7 @@ static struct ctl_table vm_table[] = { .mode = 0644, .proc_handler = proc_dointvec_minmax, .extra1 = SYSCTL_ZERO, + .extra2 = (void *)&page_cluster_max, }, { .procname = "dirtytime_expire_seconds", diff --git a/kernel/time/tick-oneshot.c b/kernel/time/tick-oneshot.c index 475ecceda768..5e2c2c26b3cc 100644 --- a/kernel/time/tick-oneshot.c +++ b/kernel/time/tick-oneshot.c @@ -18,7 +18,7 @@ #include "tick-internal.h" /** - * tick_program_event + * tick_program_event - program the CPU local timer device for the next event */ int tick_program_event(ktime_t expires, int force) { @@ -99,7 +99,7 @@ int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *)) } /** - * tick_check_oneshot_mode - check whether the system is in oneshot mode + * tick_oneshot_mode_active - check whether the system is in oneshot mode * * returns 1 when either nohz or highres are enabled. otherwise 0. */ diff --git a/kernel/time/time.c b/kernel/time/time.c index 526257b3727c..f4198af60fee 100644 --- a/kernel/time/time.c +++ b/kernel/time/time.c @@ -462,7 +462,7 @@ struct __kernel_old_timeval ns_to_kernel_old_timeval(s64 nsec) EXPORT_SYMBOL(ns_to_kernel_old_timeval); /** - * set_normalized_timespec - set timespec sec and nsec parts and normalize + * set_normalized_timespec64 - set timespec sec and nsec parts and normalize * * @ts: pointer to timespec variable to be set * @sec: seconds to set @@ -526,7 +526,7 @@ struct timespec64 ns_to_timespec64(s64 nsec) EXPORT_SYMBOL(ns_to_timespec64); /** - * msecs_to_jiffies: - convert milliseconds to jiffies + * __msecs_to_jiffies: - convert milliseconds to jiffies * @m: time in milliseconds * * conversion is done as follows: @@ -541,12 +541,12 @@ EXPORT_SYMBOL(ns_to_timespec64); * handling any 32-bit overflows. * for the details see __msecs_to_jiffies() * - * msecs_to_jiffies() checks for the passed in value being a constant + * __msecs_to_jiffies() checks for the passed in value being a constant * via __builtin_constant_p() allowing gcc to eliminate most of the * code, __msecs_to_jiffies() is called if the value passed does not * allow constant folding and the actual conversion must be done at * runtime. - * the _msecs_to_jiffies helpers are the HZ dependent conversion + * The _msecs_to_jiffies helpers are the HZ dependent conversion * routines found in include/linux/jiffies.h */ unsigned long __msecs_to_jiffies(const unsigned int m) diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index f72b9f1de178..5579ead449f2 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -1590,10 +1590,10 @@ void __weak read_persistent_clock64(struct timespec64 *ts) /** * read_persistent_wall_and_boot_offset - Read persistent clock, and also offset * from the boot. + * @wall_time: current time as returned by persistent clock + * @boot_offset: offset that is defined as wall_time - boot_time * * Weak dummy function for arches that do not yet support it. - * @wall_time: - current time as returned by persistent clock - * @boot_offset: - offset that is defined as wall_time - boot_time * * The default function calculates offset based on the current value of * local_clock(). This way architectures that support sched_clock() but don't @@ -1701,7 +1701,7 @@ static void __timekeeping_inject_sleeptime(struct timekeeper *tk, } #if defined(CONFIG_PM_SLEEP) && defined(CONFIG_RTC_HCTOSYS_DEVICE) -/** +/* * We have three kinds of time sources to use for sleep time * injection, the preference order is: * 1) non-stop clocksource @@ -1722,7 +1722,7 @@ bool timekeeping_rtc_skipresume(void) return !suspend_timing_needed; } -/** +/* * 1) can be determined whether to use or not only when doing * timekeeping_resume() which is invoked after rtc_suspend(), * so we can't skip rtc_suspend() surely if system has 1). diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 2c6611c13f99..d7043043f59c 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -82,6 +82,13 @@ config HAVE_OBJTOOL_MCOUNT help Arch supports objtool --mcount +config HAVE_OBJTOOL_NOP_MCOUNT + bool + help + Arch supports the objtool options --mcount with --mnop. + An architecture can select this if it wants to enable nop'ing + of ftrace locations. + config HAVE_C_RECORDMCOUNT bool help @@ -375,6 +382,7 @@ config SCHED_TRACER config HWLAT_TRACER bool "Tracer to detect hardware latencies (like SMIs)" select GENERIC_TRACER + select TRACER_MAX_TRACE help This tracer, when enabled will create one or more kernel threads, depending on what the cpumask file is set to, which each thread @@ -410,6 +418,7 @@ config HWLAT_TRACER config OSNOISE_TRACER bool "OS Noise tracer" select GENERIC_TRACER + select TRACER_MAX_TRACE help In the context of high-performance computing (HPC), the Operating System Noise (osnoise) refers to the interference experienced by an @@ -924,8 +933,8 @@ config RING_BUFFER_RECORD_RECURSION default y help The ring buffer has its own internal recursion. Although when - recursion happens it wont cause harm because of the protection, - but it does cause an unwanted overhead. Enabling this option will + recursion happens it won't cause harm because of the protection, + but it does cause unwanted overhead. Enabling this option will place where recursion was detected into the ftrace "recursed_functions" file. @@ -1008,8 +1017,8 @@ config RING_BUFFER_STARTUP_TEST The test runs for 10 seconds. This will slow your boot time by at least 10 more seconds. - At the end of the test, statics and more checks are done. - It will output the stats of each per cpu buffer. What + At the end of the test, statistics and more checks are done. + It will output the stats of each per cpu buffer: What was written, the sizes, what was read, what was lost, and other similar details. diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 1ed08967fb97..c09792c551bf 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -6,6 +6,7 @@ #include <linux/types.h> #include <linux/slab.h> #include <linux/bpf.h> +#include <linux/bpf_verifier.h> #include <linux/bpf_perf_event.h> #include <linux/btf.h> #include <linux/filter.h> @@ -773,7 +774,7 @@ BPF_CALL_0(bpf_get_current_task_btf) const struct bpf_func_proto bpf_get_current_task_btf_proto = { .func = bpf_get_current_task_btf, .gpl_only = true, - .ret_type = RET_PTR_TO_BTF_ID, + .ret_type = RET_PTR_TO_BTF_ID_TRUSTED, .ret_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK], }; @@ -832,6 +833,7 @@ static void do_bpf_send_signal(struct irq_work *entry) work = container_of(entry, struct send_signal_irq_work, irq_work); group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type); + put_task_struct(work->task); } static int bpf_send_signal_common(u32 sig, enum pid_type type) @@ -847,6 +849,9 @@ static int bpf_send_signal_common(u32 sig, enum pid_type type) return -EPERM; if (unlikely(!nmi_uaccess_okay())) return -EPERM; + /* Task should not be pid=1 to avoid kernel panic. */ + if (unlikely(is_global_init(current))) + return -EPERM; if (irqs_disabled()) { /* Do an early check on signal validity. Otherwise, @@ -863,7 +868,7 @@ static int bpf_send_signal_common(u32 sig, enum pid_type type) * to the irq_work. The current task may change when queued * irq works get executed. */ - work->task = current; + work->task = get_task_struct(current); work->sig = sig; work->type = type; irq_work_queue(&work->irq_work); @@ -1456,6 +1461,10 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_get_current_cgroup_id_proto; case BPF_FUNC_get_current_ancestor_cgroup_id: return &bpf_get_current_ancestor_cgroup_id_proto; + case BPF_FUNC_cgrp_storage_get: + return &bpf_cgrp_storage_get_proto; + case BPF_FUNC_cgrp_storage_delete: + return &bpf_cgrp_storage_delete_proto; #endif case BPF_FUNC_send_signal: return &bpf_send_signal_proto; @@ -1480,9 +1489,9 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_get_task_stack: return &bpf_get_task_stack_proto; case BPF_FUNC_copy_from_user: - return prog->aux->sleepable ? &bpf_copy_from_user_proto : NULL; + return &bpf_copy_from_user_proto; case BPF_FUNC_copy_from_user_task: - return prog->aux->sleepable ? &bpf_copy_from_user_task_proto : NULL; + return &bpf_copy_from_user_task_proto; case BPF_FUNC_snprintf_btf: return &bpf_snprintf_btf_proto; case BPF_FUNC_per_cpu_ptr: @@ -1490,8 +1499,12 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_this_cpu_ptr: return &bpf_this_cpu_ptr_proto; case BPF_FUNC_task_storage_get: + if (bpf_prog_check_recur(prog)) + return &bpf_task_storage_get_recur_proto; return &bpf_task_storage_get_proto; case BPF_FUNC_task_storage_delete: + if (bpf_prog_check_recur(prog)) + return &bpf_task_storage_delete_recur_proto; return &bpf_task_storage_delete_proto; case BPF_FUNC_for_each_map_elem: return &bpf_for_each_map_elem_proto; @@ -2452,6 +2465,8 @@ struct bpf_kprobe_multi_link { unsigned long *addrs; u64 *cookies; u32 cnt; + u32 mods_cnt; + struct module **mods; }; struct bpf_kprobe_multi_run_ctx { @@ -2507,6 +2522,14 @@ error: return err; } +static void kprobe_multi_put_modules(struct module **mods, u32 cnt) +{ + u32 i; + + for (i = 0; i < cnt; i++) + module_put(mods[i]); +} + static void free_user_syms(struct user_syms *us) { kvfree(us->syms); @@ -2519,6 +2542,7 @@ static void bpf_kprobe_multi_link_release(struct bpf_link *link) kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link); unregister_fprobe(&kmulti_link->fp); + kprobe_multi_put_modules(kmulti_link->mods, kmulti_link->mods_cnt); } static void bpf_kprobe_multi_link_dealloc(struct bpf_link *link) @@ -2528,6 +2552,7 @@ static void bpf_kprobe_multi_link_dealloc(struct bpf_link *link) kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link); kvfree(kmulti_link->addrs); kvfree(kmulti_link->cookies); + kfree(kmulti_link->mods); kfree(kmulti_link); } @@ -2550,7 +2575,7 @@ static void bpf_kprobe_multi_cookie_swap(void *a, void *b, int size, const void swap(*cookie_a, *cookie_b); } -static int __bpf_kprobe_multi_cookie_cmp(const void *a, const void *b) +static int bpf_kprobe_multi_addrs_cmp(const void *a, const void *b) { const unsigned long *addr_a = a, *addr_b = b; @@ -2561,7 +2586,7 @@ static int __bpf_kprobe_multi_cookie_cmp(const void *a, const void *b) static int bpf_kprobe_multi_cookie_cmp(const void *a, const void *b, const void *priv) { - return __bpf_kprobe_multi_cookie_cmp(a, b); + return bpf_kprobe_multi_addrs_cmp(a, b); } static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx) @@ -2579,7 +2604,7 @@ static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx) return 0; entry_ip = run_ctx->entry_ip; addr = bsearch(&entry_ip, link->addrs, link->cnt, sizeof(entry_ip), - __bpf_kprobe_multi_cookie_cmp); + bpf_kprobe_multi_addrs_cmp); if (!addr) return 0; cookie = link->cookies + (addr - link->addrs); @@ -2663,6 +2688,71 @@ static void symbols_swap_r(void *a, void *b, int size, const void *priv) } } +struct module_addr_args { + unsigned long *addrs; + u32 addrs_cnt; + struct module **mods; + int mods_cnt; + int mods_cap; +}; + +static int module_callback(void *data, const char *name, + struct module *mod, unsigned long addr) +{ + struct module_addr_args *args = data; + struct module **mods; + + /* We iterate all modules symbols and for each we: + * - search for it in provided addresses array + * - if found we check if we already have the module pointer stored + * (we iterate modules sequentially, so we can check just the last + * module pointer) + * - take module reference and store it + */ + if (!bsearch(&addr, args->addrs, args->addrs_cnt, sizeof(addr), + bpf_kprobe_multi_addrs_cmp)) + return 0; + + if (args->mods && args->mods[args->mods_cnt - 1] == mod) + return 0; + + if (args->mods_cnt == args->mods_cap) { + args->mods_cap = max(16, args->mods_cap * 3 / 2); + mods = krealloc_array(args->mods, args->mods_cap, sizeof(*mods), GFP_KERNEL); + if (!mods) + return -ENOMEM; + args->mods = mods; + } + + if (!try_module_get(mod)) + return -EINVAL; + + args->mods[args->mods_cnt] = mod; + args->mods_cnt++; + return 0; +} + +static int get_modules_for_addrs(struct module ***mods, unsigned long *addrs, u32 addrs_cnt) +{ + struct module_addr_args args = { + .addrs = addrs, + .addrs_cnt = addrs_cnt, + }; + int err; + + /* We return either err < 0 in case of error, ... */ + err = module_kallsyms_on_each_symbol(module_callback, &args); + if (err) { + kprobe_multi_put_modules(args.mods, args.mods_cnt); + kfree(args.mods); + return err; + } + + /* or number of modules found if everything is ok. */ + *mods = args.mods; + return args.mods_cnt; +} + int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) { struct bpf_kprobe_multi_link *link = NULL; @@ -2773,10 +2863,25 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr bpf_kprobe_multi_cookie_cmp, bpf_kprobe_multi_cookie_swap, link); + } else { + /* + * We need to sort addrs array even if there are no cookies + * provided, to allow bsearch in get_modules_for_addrs. + */ + sort(addrs, cnt, sizeof(*addrs), + bpf_kprobe_multi_addrs_cmp, NULL); + } + + err = get_modules_for_addrs(&link->mods, addrs, cnt); + if (err < 0) { + bpf_link_cleanup(&link_primer); + return err; } + link->mods_cnt = err; err = register_fprobe_ips(&link->fp, addrs, cnt); if (err) { + kprobe_multi_put_modules(link->mods, link->mods_cnt); bpf_link_cleanup(&link_primer); return err; } diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index acfa4e029bcc..750aa3f08b25 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -163,7 +163,7 @@ static void ftrace_sync_ipi(void *data) static ftrace_func_t ftrace_ops_get_list_func(struct ftrace_ops *ops) { /* - * If this is a dynamic, RCU, or per CPU ops, or we force list func, + * If this is a dynamic or RCU ops, or we force list func, * then it needs to call the list anyway. */ if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_RCU) || @@ -1248,12 +1248,17 @@ static void free_ftrace_hash_rcu(struct ftrace_hash *hash) call_rcu(&hash->rcu, __free_ftrace_hash_rcu); } +/** + * ftrace_free_filter - remove all filters for an ftrace_ops + * @ops - the ops to remove the filters from + */ void ftrace_free_filter(struct ftrace_ops *ops) { ftrace_ops_init(ops); free_ftrace_hash(ops->func_hash->filter_hash); free_ftrace_hash(ops->func_hash->notrace_hash); } +EXPORT_SYMBOL_GPL(ftrace_free_filter); static struct ftrace_hash *alloc_ftrace_hash(int size_bits) { @@ -2762,6 +2767,19 @@ void __weak ftrace_arch_code_modify_post_process(void) { } +static int update_ftrace_func(ftrace_func_t func) +{ + static ftrace_func_t save_func; + + /* Avoid updating if it hasn't changed */ + if (func == save_func) + return 0; + + save_func = func; + + return ftrace_update_ftrace_func(func); +} + void ftrace_modify_all_code(int command) { int update = command & FTRACE_UPDATE_TRACE_FUNC; @@ -2782,7 +2800,7 @@ void ftrace_modify_all_code(int command) * traced. */ if (update) { - err = ftrace_update_ftrace_func(ftrace_ops_list_func); + err = update_ftrace_func(ftrace_ops_list_func); if (FTRACE_WARN_ON(err)) return; } @@ -2798,7 +2816,7 @@ void ftrace_modify_all_code(int command) /* If irqs are disabled, we are in stop machine */ if (!irqs_disabled()) smp_call_function(ftrace_sync_ipi, NULL, 1); - err = ftrace_update_ftrace_func(ftrace_trace_function); + err = update_ftrace_func(ftrace_trace_function); if (FTRACE_WARN_ON(err)) return; } @@ -3070,8 +3088,6 @@ out: /* * Dynamic ops may be freed, we must make sure that all * callers are done before leaving this function. - * The same goes for freeing the per_cpu data of the per_cpu - * ops. */ if (ops->flags & FTRACE_OPS_FL_DYNAMIC) { /* @@ -4192,6 +4208,7 @@ match_records(struct ftrace_hash *hash, char *func, int len, char *mod) } found = 1; } + cond_resched(); } while_for_each_ftrace_rec(); out_unlock: mutex_unlock(&ftrace_lock); @@ -5827,6 +5844,10 @@ EXPORT_SYMBOL_GPL(modify_ftrace_direct_multi); * * Filters denote which functions should be enabled when tracing is enabled * If @ip is NULL, it fails to update filter. + * + * This can allocate memory which must be freed before @ops can be freed, + * either by removing each filtered addr or by using + * ftrace_free_filter(@ops). */ int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, int remove, int reset) @@ -5846,7 +5867,11 @@ EXPORT_SYMBOL_GPL(ftrace_set_filter_ip); * * Filters denote which functions should be enabled when tracing is enabled * If @ips array or any ip specified within is NULL , it fails to update filter. - */ + * + * This can allocate memory which must be freed before @ops can be freed, + * either by removing each filtered addr or by using + * ftrace_free_filter(@ops). +*/ int ftrace_set_filter_ips(struct ftrace_ops *ops, unsigned long *ips, unsigned int cnt, int remove, int reset) { @@ -5888,6 +5913,10 @@ ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, * * Filters denote which functions should be enabled when tracing is enabled. * If @buf is NULL and reset is set, all functions will be enabled for tracing. + * + * This can allocate memory which must be freed before @ops can be freed, + * either by removing each filtered addr or by using + * ftrace_free_filter(@ops). */ int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, int len, int reset) @@ -5907,6 +5936,10 @@ EXPORT_SYMBOL_GPL(ftrace_set_filter); * Notrace Filters denote which functions should not be enabled when tracing * is enabled. If @buf is NULL and reset is set, all functions will be enabled * for tracing. + * + * This can allocate memory which must be freed before @ops can be freed, + * either by removing each filtered addr or by using + * ftrace_free_filter(@ops). */ int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, int len, int reset) @@ -7518,8 +7551,6 @@ __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, /* * Check the following for each ops before calling their func: * if RCU flag is set, then rcu_is_watching() must be true - * if PER_CPU is set, then ftrace_function_local_disable() - * must be false * Otherwise test if the ip matches the ops filter * * If any of the above fails then the op->func() is not executed. @@ -7569,8 +7600,8 @@ NOKPROBE_SYMBOL(arch_ftrace_ops_list_func); /* * If there's only one function registered but it does not support - * recursion, needs RCU protection and/or requires per cpu handling, then - * this function will be called by the mcount trampoline. + * recursion, needs RCU protection, then this function will be called + * by the mcount trampoline. */ static void ftrace_ops_assist_func(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs) @@ -8257,6 +8288,10 @@ struct kallsyms_data { size_t found; }; +/* This function gets called for all kernel and module symbols + * and returns 1 in case we resolved all the requested symbols, + * 0 otherwise. + */ static int kallsyms_callback(void *data, const char *name, struct module *mod, unsigned long addr) { @@ -8299,17 +8334,19 @@ static int kallsyms_callback(void *data, const char *name, int ftrace_lookup_symbols(const char **sorted_syms, size_t cnt, unsigned long *addrs) { struct kallsyms_data args; - int err; + int found_all; memset(addrs, 0, sizeof(*addrs) * cnt); args.addrs = addrs; args.syms = sorted_syms; args.cnt = cnt; args.found = 0; - err = kallsyms_on_each_symbol(kallsyms_callback, &args); - if (err < 0) - return err; - return args.found == args.cnt ? 0 : -ESRCH; + + found_all = kallsyms_on_each_symbol(kallsyms_callback, &args); + if (found_all) + return 0; + found_all = module_kallsyms_on_each_symbol(kallsyms_callback, &args); + return found_all ? 0 : -ESRCH; } #ifdef CONFIG_SYSCTL diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index b21bf14bae9b..c366a0a9ddba 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -2062,8 +2062,10 @@ rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer) { struct list_head *pages = &cpu_buffer->new_pages; int retries, success; + unsigned long flags; - raw_spin_lock_irq(&cpu_buffer->reader_lock); + /* Can be called at early boot up, where interrupts must not been enabled */ + raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags); /* * We are holding the reader lock, so the reader page won't be swapped * in the ring buffer. Now we are racing with the writer trying to @@ -2120,7 +2122,7 @@ rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer) * tracing */ RB_WARN_ON(cpu_buffer, !success); - raw_spin_unlock_irq(&cpu_buffer->reader_lock); + raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); /* free pages if they weren't inserted */ if (!success) { @@ -2248,8 +2250,16 @@ int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size, rb_update_pages(cpu_buffer); cpu_buffer->nr_pages_to_update = 0; } else { - schedule_work_on(cpu, - &cpu_buffer->update_pages_work); + /* Run directly if possible. */ + migrate_disable(); + if (cpu != smp_processor_id()) { + migrate_enable(); + schedule_work_on(cpu, + &cpu_buffer->update_pages_work); + } else { + update_pages_handler(&cpu_buffer->update_pages_work); + migrate_enable(); + } } } @@ -2298,9 +2308,17 @@ int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size, if (!cpu_online(cpu_id)) rb_update_pages(cpu_buffer); else { - schedule_work_on(cpu_id, - &cpu_buffer->update_pages_work); - wait_for_completion(&cpu_buffer->update_done); + /* Run directly if possible. */ + migrate_disable(); + if (cpu_id == smp_processor_id()) { + rb_update_pages(cpu_buffer); + migrate_enable(); + } else { + migrate_enable(); + schedule_work_on(cpu_id, + &cpu_buffer->update_pages_work); + wait_for_completion(&cpu_buffer->update_done); + } } cpu_buffer->nr_pages_to_update = 0; @@ -3180,8 +3198,7 @@ static inline void rb_event_discard(struct ring_buffer_event *event) event->time_delta = 1; } -static void rb_commit(struct ring_buffer_per_cpu *cpu_buffer, - struct ring_buffer_event *event) +static void rb_commit(struct ring_buffer_per_cpu *cpu_buffer) { local_inc(&cpu_buffer->entries); rb_end_commit(cpu_buffer); @@ -3383,15 +3400,14 @@ void ring_buffer_nest_end(struct trace_buffer *buffer) * * Must be paired with ring_buffer_lock_reserve. */ -int ring_buffer_unlock_commit(struct trace_buffer *buffer, - struct ring_buffer_event *event) +int ring_buffer_unlock_commit(struct trace_buffer *buffer) { struct ring_buffer_per_cpu *cpu_buffer; int cpu = raw_smp_processor_id(); cpu_buffer = buffer->buffers[cpu]; - rb_commit(cpu_buffer, event); + rb_commit(cpu_buffer); rb_wakeups(buffer, cpu_buffer); @@ -3977,7 +3993,7 @@ int ring_buffer_write(struct trace_buffer *buffer, memcpy(body, data, length); - rb_commit(cpu_buffer, event); + rb_commit(cpu_buffer); rb_wakeups(buffer, cpu_buffer); @@ -5998,7 +6014,7 @@ static __init int rb_write_something(struct rb_test_data *data, bool nested) } out: - ring_buffer_unlock_commit(data->buffer, event); + ring_buffer_unlock_commit(data->buffer); return 0; } diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c index 78e576575b79..aef34673d79d 100644 --- a/kernel/trace/ring_buffer_benchmark.c +++ b/kernel/trace/ring_buffer_benchmark.c @@ -258,7 +258,7 @@ static void ring_buffer_producer(void) hit++; entry = ring_buffer_event_data(event); *entry = smp_processor_id(); - ring_buffer_unlock_commit(buffer, event); + ring_buffer_unlock_commit(buffer); } } end_time = ktime_get(); diff --git a/kernel/trace/rv/monitors/wip/wip.h b/kernel/trace/rv/monitors/wip/wip.h index dacc37b62a2c..2e373f2c65ed 100644 --- a/kernel/trace/rv/monitors/wip/wip.h +++ b/kernel/trace/rv/monitors/wip/wip.h @@ -27,7 +27,7 @@ struct automaton_wip { bool final_states[state_max_wip]; }; -static struct automaton_wip automaton_wip = { +static const struct automaton_wip automaton_wip = { .state_names = { "preemptive", "non_preemptive" diff --git a/kernel/trace/rv/monitors/wwnr/wwnr.h b/kernel/trace/rv/monitors/wwnr/wwnr.h index 118e576b91b4..d0d9c4b8121b 100644 --- a/kernel/trace/rv/monitors/wwnr/wwnr.h +++ b/kernel/trace/rv/monitors/wwnr/wwnr.h @@ -27,7 +27,7 @@ struct automaton_wwnr { bool final_states[state_max_wwnr]; }; -static struct automaton_wwnr automaton_wwnr = { +static const struct automaton_wwnr automaton_wwnr = { .state_names = { "not_running", "running" diff --git a/kernel/trace/rv/rv.c b/kernel/trace/rv/rv.c index 6c97cc2d754a..7e9061828c24 100644 --- a/kernel/trace/rv/rv.c +++ b/kernel/trace/rv/rv.c @@ -516,7 +516,7 @@ static ssize_t enabled_monitors_write(struct file *filp, const char __user *user struct rv_monitor_def *mdef; int retval = -EINVAL; bool enable = true; - char *ptr = buff; + char *ptr; int len; if (count < 1 || count > MAX_RV_MONITOR_NAME_SIZE + 1) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 5cfc95a52bc3..c9e40f692650 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -19,7 +19,6 @@ #include <linux/kallsyms.h> #include <linux/security.h> #include <linux/seq_file.h> -#include <linux/notifier.h> #include <linux/irqflags.h> #include <linux/debugfs.h> #include <linux/tracefs.h> @@ -85,7 +84,7 @@ void __init disable_tracing_selftest(const char *reason) #endif /* Pipe tracepoints to printk */ -struct trace_iterator *tracepoint_print_iter; +static struct trace_iterator *tracepoint_print_iter; int tracepoint_printk; static bool tracepoint_printk_stop_on_boot __initdata; static DEFINE_STATIC_KEY_FALSE(tracepoint_printk_key); @@ -999,7 +998,7 @@ __buffer_unlock_commit(struct trace_buffer *buffer, struct ring_buffer_event *ev /* ring_buffer_unlock_commit() enables preemption */ preempt_enable_notrace(); } else - ring_buffer_unlock_commit(buffer, event); + ring_buffer_unlock_commit(buffer); } /** @@ -1421,6 +1420,7 @@ int tracing_snapshot_cond_disable(struct trace_array *tr) return false; } EXPORT_SYMBOL_GPL(tracing_snapshot_cond_disable); +#define free_snapshot(tr) do { } while (0) #endif /* CONFIG_TRACER_SNAPSHOT */ void tracer_tracing_off(struct trace_array *tr) @@ -1692,6 +1692,8 @@ static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) } unsigned long __read_mostly tracing_thresh; + +#ifdef CONFIG_TRACER_MAX_TRACE static const struct file_operations tracing_max_lat_fops; #ifdef LATENCY_FS_NOTIFY @@ -1748,18 +1750,14 @@ void latency_fsnotify(struct trace_array *tr) irq_work_queue(&tr->fsnotify_irqwork); } -#elif defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) \ - || defined(CONFIG_OSNOISE_TRACER) +#else /* !LATENCY_FS_NOTIFY */ #define trace_create_maxlat_file(tr, d_tracer) \ trace_create_file("tracing_max_latency", TRACE_MODE_WRITE, \ d_tracer, &tr->max_latency, &tracing_max_lat_fops) -#else -#define trace_create_maxlat_file(tr, d_tracer) do { } while (0) #endif -#ifdef CONFIG_TRACER_MAX_TRACE /* * Copy the new maximum trace into the separate maximum-trace * structure. (this way the maximum trace is permanently saved, @@ -1834,14 +1832,15 @@ update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu, ring_buffer_record_off(tr->max_buffer.buffer); #ifdef CONFIG_TRACER_SNAPSHOT - if (tr->cond_snapshot && !tr->cond_snapshot->update(tr, cond_data)) - goto out_unlock; + if (tr->cond_snapshot && !tr->cond_snapshot->update(tr, cond_data)) { + arch_spin_unlock(&tr->max_lock); + return; + } #endif swap(tr->array_buffer.buffer, tr->max_buffer.buffer); __update_max_tr(tr, tsk, cpu); - out_unlock: arch_spin_unlock(&tr->max_lock); } @@ -1888,6 +1887,7 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) __update_max_tr(tr, tsk, cpu); arch_spin_unlock(&tr->max_lock); } + #endif /* CONFIG_TRACER_MAX_TRACE */ static int wait_on_pipe(struct trace_iterator *iter, int full) @@ -5617,7 +5617,7 @@ static const char readme_msg[] = "\t +|-[u]<offset>(<fetcharg>), \\imm-value, \\\"imm-string\"\n" "\t type: s8/16/32/64, u8/16/32/64, x8/16/32/64, string, symbol,\n" "\t b<bit-width>@<bit-offset>/<container-size>, ustring,\n" - "\t <type>\\[<array-size>\\]\n" + "\t symstr, <type>\\[<array-size>\\]\n" #ifdef CONFIG_HIST_TRIGGERS "\t field: <stype> <name>;\n" "\t stype: u8/u16/u32/u64, s8/s16/s32/s64, pid_t,\n" @@ -5678,6 +5678,7 @@ static const char readme_msg[] = "\t [:size=#entries]\n" "\t [:pause][:continue][:clear]\n" "\t [:name=histname1]\n" + "\t [:nohitcount]\n" "\t [:<handler>.<action>]\n" "\t [if <filter>]\n\n" "\t Note, special fields can be used as well:\n" @@ -5724,7 +5725,9 @@ static const char readme_msg[] = "\t .syscall display a syscall id as a syscall name\n" "\t .log2 display log2 value rather than raw number\n" "\t .buckets=size display values in groups of size rather than raw number\n" - "\t .usecs display a common_timestamp in microseconds\n\n" + "\t .usecs display a common_timestamp in microseconds\n" + "\t .percent display a number of percentage value\n" + "\t .graph display a bar-graph of a value\n\n" "\t The 'pause' parameter can be used to pause an existing hist\n" "\t trigger or to start a hist trigger but not log any events\n" "\t until told to do so. 'continue' can be used to start or\n" @@ -5732,6 +5735,8 @@ static const char readme_msg[] = "\t The 'clear' parameter will clear the contents of a running\n" "\t hist trigger and leave its current paused/active state\n" "\t unchanged.\n\n" + "\t The 'nohitcount' (or NOHC) parameter will suppress display of\n" + "\t raw hitcount in the histogram.\n\n" "\t The enable_hist and disable_hist triggers can be used to\n" "\t have one event conditionally start and stop another event's\n" "\t already-attached hist trigger. The syntax is analogous to\n" @@ -6572,7 +6577,7 @@ out: return ret; } -#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) +#ifdef CONFIG_TRACER_MAX_TRACE static ssize_t tracing_max_lat_read(struct file *filp, char __user *ubuf, @@ -6796,7 +6801,20 @@ waitagain: ret = print_trace_line(iter); if (ret == TRACE_TYPE_PARTIAL_LINE) { - /* don't print partial lines */ + /* + * If one print_trace_line() fills entire trace_seq in one shot, + * trace_seq_to_user() will returns -EBUSY because save_len == 0, + * In this case, we need to consume it, otherwise, loop will peek + * this event next time, resulting in an infinite loop. + */ + if (save_len == 0) { + iter->seq.full = 0; + trace_seq_puts(&iter->seq, "[LINE TOO BIG]\n"); + trace_consume(iter); + break; + } + + /* In other cases, don't print partial lines */ iter->seq.seq.len = save_len; break; } @@ -7587,7 +7605,7 @@ static const struct file_operations tracing_thresh_fops = { .llseek = generic_file_llseek, }; -#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) +#ifdef CONFIG_TRACER_MAX_TRACE static const struct file_operations tracing_max_lat_fops = { .open = tracing_open_generic, .read = tracing_max_lat_read, @@ -9130,9 +9148,6 @@ buffer_percent_write(struct file *filp, const char __user *ubuf, if (val > 100) return -EINVAL; - if (!val) - val = 1; - tr->buffer_percent = val; (*ppos)++; @@ -9601,7 +9616,9 @@ init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer) create_trace_options_dir(tr); +#ifdef CONFIG_TRACER_MAX_TRACE trace_create_maxlat_file(tr, d_tracer); +#endif if (ftrace_create_function_files(tr, d_tracer)) MEM_FAIL(1, "Could not allocate function filter files"); @@ -9855,41 +9872,41 @@ static __init int tracer_init_tracefs(void) fs_initcall(tracer_init_tracefs); -static int trace_panic_handler(struct notifier_block *this, - unsigned long event, void *unused) -{ - if (ftrace_dump_on_oops) - ftrace_dump(ftrace_dump_on_oops); - return NOTIFY_OK; -} +static int trace_die_panic_handler(struct notifier_block *self, + unsigned long ev, void *unused); static struct notifier_block trace_panic_notifier = { - .notifier_call = trace_panic_handler, - .next = NULL, - .priority = 150 /* priority: INT_MAX >= x >= 0 */ + .notifier_call = trace_die_panic_handler, + .priority = INT_MAX - 1, }; -static int trace_die_handler(struct notifier_block *self, - unsigned long val, - void *data) -{ - switch (val) { - case DIE_OOPS: - if (ftrace_dump_on_oops) - ftrace_dump(ftrace_dump_on_oops); - break; - default: - break; - } - return NOTIFY_OK; -} - static struct notifier_block trace_die_notifier = { - .notifier_call = trace_die_handler, - .priority = 200 + .notifier_call = trace_die_panic_handler, + .priority = INT_MAX - 1, }; /* + * The idea is to execute the following die/panic callback early, in order + * to avoid showing irrelevant information in the trace (like other panic + * notifier functions); we are the 2nd to run, after hung_task/rcu_stall + * warnings get disabled (to prevent potential log flooding). + */ +static int trace_die_panic_handler(struct notifier_block *self, + unsigned long ev, void *unused) +{ + if (!ftrace_dump_on_oops) + return NOTIFY_DONE; + + /* The die notifier requires DIE_OOPS to trigger */ + if (self == &trace_die_notifier && ev != DIE_OOPS) + return NOTIFY_DONE; + + ftrace_dump(ftrace_dump_on_oops); + + return NOTIFY_DONE; +} + +/* * printk is set to max of 1024, we really don't need it that big. * Nothing should be printing 1000 characters anyway. */ @@ -10275,6 +10292,8 @@ void __init early_trace_init(void) static_key_enable(&tracepoint_printk_key.key); } tracer_alloc_buffers(); + + init_events(); } void __init trace_init(void) diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index d42e24507152..4eb6d6b97a9f 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -308,8 +308,7 @@ struct trace_array { struct array_buffer max_buffer; bool allocated_snapshot; #endif -#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) \ - || defined(CONFIG_OSNOISE_TRACER) +#ifdef CONFIG_TRACER_MAX_TRACE unsigned long max_latency; #ifdef CONFIG_FSNOTIFY struct dentry *d_max_latency; @@ -615,7 +614,7 @@ void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer, bool trace_is_tracepoint_string(const char *str); const char *trace_event_format(struct trace_iterator *iter, const char *fmt); void trace_check_vprintf(struct trace_iterator *iter, const char *fmt, - va_list ap); + va_list ap) __printf(2, 0); int trace_empty(struct trace_iterator *iter); @@ -688,12 +687,11 @@ void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu, void *cond_data); void update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu); -#endif /* CONFIG_TRACER_MAX_TRACE */ -#if (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) \ - || defined(CONFIG_OSNOISE_TRACER)) && defined(CONFIG_FSNOTIFY) +#ifdef CONFIG_FSNOTIFY #define LATENCY_FS_NOTIFY #endif +#endif /* CONFIG_TRACER_MAX_TRACE */ #ifdef LATENCY_FS_NOTIFY void latency_fsnotify(struct trace_array *tr); @@ -1492,6 +1490,7 @@ extern void trace_event_enable_cmd_record(bool enable); extern void trace_event_enable_tgid_record(bool enable); extern int event_trace_init(void); +extern int init_events(void); extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr); extern int event_trace_del_tracer(struct trace_array *tr); extern void __trace_early_add_events(struct trace_array *tr); @@ -1942,8 +1941,6 @@ static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { } static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { } #endif -extern struct trace_iterator *tracepoint_print_iter; - /* * Reset the state of the trace_iterator so that it can read consumed data. * Normally, the trace_iterator is used for reading the data when it is not @@ -1956,17 +1953,30 @@ static __always_inline void trace_iterator_reset(struct trace_iterator *iter) } /* Check the name is good for event/group/fields */ -static inline bool is_good_name(const char *name) +static inline bool __is_good_name(const char *name, bool hash_ok) { - if (!isalpha(*name) && *name != '_') + if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-')) return false; while (*++name != '\0') { - if (!isalpha(*name) && !isdigit(*name) && *name != '_') + if (!isalpha(*name) && !isdigit(*name) && *name != '_' && + (!hash_ok || *name != '-')) return false; } return true; } +/* Check the name is good for event/group/fields */ +static inline bool is_good_name(const char *name) +{ + return __is_good_name(name, false); +} + +/* Check the name is good for system */ +static inline bool is_good_system_name(const char *name) +{ + return __is_good_name(name, true); +} + /* Convert certain expected symbols into '_' when generating event names */ static inline void sanitize_event_name(char *name) { diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c index 61e3a2620fa3..05e791241812 100644 --- a/kernel/trace/trace_event_perf.c +++ b/kernel/trace/trace_event_perf.c @@ -251,16 +251,12 @@ int perf_kprobe_init(struct perf_event *p_event, bool is_retprobe) struct trace_event_call *tp_event; if (p_event->attr.kprobe_func) { - func = kzalloc(KSYM_NAME_LEN, GFP_KERNEL); - if (!func) - return -ENOMEM; - ret = strncpy_from_user( - func, u64_to_user_ptr(p_event->attr.kprobe_func), - KSYM_NAME_LEN); - if (ret == KSYM_NAME_LEN) - ret = -E2BIG; - if (ret < 0) - goto out; + func = strndup_user(u64_to_user_ptr(p_event->attr.kprobe_func), + KSYM_NAME_LEN); + if (IS_ERR(func)) { + ret = PTR_ERR(func); + return (ret == -EINVAL) ? -E2BIG : ret; + } if (func[0] == '\0') { kfree(func); diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index f71ea6e79b3c..33e0b4f8ebe6 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -2796,6 +2796,42 @@ trace_create_new_event(struct trace_event_call *call, return file; } +#define MAX_BOOT_TRIGGERS 32 + +static struct boot_triggers { + const char *event; + char *trigger; +} bootup_triggers[MAX_BOOT_TRIGGERS]; + +static char bootup_trigger_buf[COMMAND_LINE_SIZE]; +static int nr_boot_triggers; + +static __init int setup_trace_triggers(char *str) +{ + char *trigger; + char *buf; + int i; + + strlcpy(bootup_trigger_buf, str, COMMAND_LINE_SIZE); + ring_buffer_expanded = true; + disable_tracing_selftest("running event triggers"); + + buf = bootup_trigger_buf; + for (i = 0; i < MAX_BOOT_TRIGGERS; i++) { + trigger = strsep(&buf, ","); + if (!trigger) + break; + bootup_triggers[i].event = strsep(&trigger, "."); + bootup_triggers[i].trigger = strsep(&trigger, "."); + if (!bootup_triggers[i].trigger) + break; + } + + nr_boot_triggers = i; + return 1; +} +__setup("trace_trigger=", setup_trace_triggers); + /* Add an event to a trace directory */ static int __trace_add_new_event(struct trace_event_call *call, struct trace_array *tr) @@ -2812,6 +2848,24 @@ __trace_add_new_event(struct trace_event_call *call, struct trace_array *tr) return event_define_fields(call); } +static void trace_early_triggers(struct trace_event_file *file, const char *name) +{ + int ret; + int i; + + for (i = 0; i < nr_boot_triggers; i++) { + if (strcmp(name, bootup_triggers[i].event)) + continue; + mutex_lock(&event_mutex); + ret = trigger_process_regex(file, bootup_triggers[i].trigger); + mutex_unlock(&event_mutex); + if (ret) + pr_err("Failed to register trigger '%s' on event %s\n", + bootup_triggers[i].trigger, + bootup_triggers[i].event); + } +} + /* * Just create a descriptor for early init. A descriptor is required * for enabling events at boot. We want to enable events before @@ -2822,12 +2876,19 @@ __trace_early_add_new_event(struct trace_event_call *call, struct trace_array *tr) { struct trace_event_file *file; + int ret; file = trace_create_new_event(call, tr); if (!file) return -ENOMEM; - return event_define_fields(call); + ret = event_define_fields(call); + if (ret) + return ret; + + trace_early_triggers(file, trace_event_name(call)); + + return 0; } struct ftrace_module_file_ops; @@ -3735,6 +3796,8 @@ static __init int event_trace_enable(void) list_add(&call->list, &ftrace_events); } + register_trigger_cmds(); + /* * We need the top trace array to have a working set of trace * points at early init, before the debug files and directories @@ -3749,7 +3812,6 @@ static __init int event_trace_enable(void) register_event_cmds(); - register_trigger_cmds(); return 0; } diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 96acc2b71ac7..e095c3b3a50d 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -128,7 +128,7 @@ static bool is_not(const char *str) } /** - * prog_entry - a singe entry in the filter program + * struct prog_entry - a singe entry in the filter program * @target: Index to jump to on a branch (actually one minus the index) * @when_to_branch: The value of the result of the predicate to do a branch * @pred: The predicate to execute. @@ -140,16 +140,16 @@ struct prog_entry { }; /** - * update_preds- assign a program entry a label target + * update_preds - assign a program entry a label target * @prog: The program array * @N: The index of the current entry in @prog - * @when_to_branch: What to assign a program entry for its branch condition + * @invert: What to assign a program entry for its branch condition * * The program entry at @N has a target that points to the index of a program * entry that can have its target and when_to_branch fields updated. * Update the current program entry denoted by index @N target field to be * that of the updated entry. This will denote the entry to update if - * we are processing an "||" after an "&&" + * we are processing an "||" after an "&&". */ static void update_preds(struct prog_entry *prog, int N, int invert) { diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 1c82478e8dff..5edbf6b1da3f 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -69,7 +69,8 @@ C(INVALID_STR_OPERAND, "String type can not be an operand in expression"), \ C(EXPECT_NUMBER, "Expecting numeric literal"), \ C(UNARY_MINUS_SUBEXPR, "Unary minus not supported in sub-expressions"), \ - C(DIVISION_BY_ZERO, "Division by zero"), + C(DIVISION_BY_ZERO, "Division by zero"), \ + C(NEED_NOHC_VAL, "Non-hitcount value is required for 'nohitcount'"), #undef C #define C(a, b) HIST_ERR_##a @@ -506,6 +507,8 @@ enum hist_field_flags { HIST_FIELD_FL_ALIAS = 1 << 16, HIST_FIELD_FL_BUCKET = 1 << 17, HIST_FIELD_FL_CONST = 1 << 18, + HIST_FIELD_FL_PERCENT = 1 << 19, + HIST_FIELD_FL_GRAPH = 1 << 20, }; struct var_defs { @@ -524,6 +527,7 @@ struct hist_trigger_attrs { bool cont; bool clear; bool ts_in_usecs; + bool no_hitcount; unsigned int map_bits; char *assignment_str[TRACING_MAP_VARS_MAX]; @@ -617,7 +621,7 @@ struct action_data { * event param, and is passed to the synthetic event * invocation. */ - unsigned int var_ref_idx[TRACING_MAP_VARS_MAX]; + unsigned int var_ref_idx[SYNTH_FIELDS_MAX]; struct synth_event *synth_event; bool use_trace_keyword; char *synth_event_name; @@ -1356,6 +1360,8 @@ static const char *hist_field_name(struct hist_field *field, field_name = field->name; } else if (field->flags & HIST_FIELD_FL_TIMESTAMP) field_name = "common_timestamp"; + else if (field->flags & HIST_FIELD_FL_HITCOUNT) + field_name = "hitcount"; if (field_name == NULL) field_name = ""; @@ -1546,7 +1552,10 @@ parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str) ret = parse_assignment(tr, str, attrs); if (ret) goto free; - } else if (strcmp(str, "pause") == 0) + } else if (strcmp(str, "nohitcount") == 0 || + strcmp(str, "NOHC") == 0) + attrs->no_hitcount = true; + else if (strcmp(str, "pause") == 0) attrs->pause = true; else if ((strcmp(str, "cont") == 0) || (strcmp(str, "continue") == 0)) @@ -1705,6 +1714,10 @@ static const char *get_hist_field_flags(struct hist_field *hist_field) flags_str = "buckets"; else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS) flags_str = "usecs"; + else if (hist_field->flags & HIST_FIELD_FL_PERCENT) + flags_str = "percent"; + else if (hist_field->flags & HIST_FIELD_FL_GRAPH) + flags_str = "graph"; return flags_str; } @@ -1975,6 +1988,8 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data, hist_field->fn_num = flags & HIST_FIELD_FL_LOG2 ? HIST_FIELD_FN_LOG2 : HIST_FIELD_FN_BUCKET; hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL); + if (!hist_field->operands[0]) + goto free; hist_field->size = hist_field->operands[0]->size; hist_field->type = kstrdup_const(hist_field->operands[0]->type, GFP_KERNEL); if (!hist_field->type) @@ -2173,7 +2188,9 @@ static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, return ref_field; } } - + /* Sanity check to avoid out-of-bound write on 'hist_data->var_refs' */ + if (hist_data->n_var_refs >= TRACING_MAP_VARS_MAX) + return NULL; ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL); if (ref_field) { if (init_var_ref(ref_field, var_field, system, event_name)) { @@ -2313,6 +2330,14 @@ parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, if (ret || !(*buckets)) goto error; *flags |= HIST_FIELD_FL_BUCKET; + } else if (strncmp(modifier, "percent", 7) == 0) { + if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY)) + goto error; + *flags |= HIST_FIELD_FL_PERCENT; + } else if (strncmp(modifier, "graph", 5) == 0) { + if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY)) + goto error; + *flags |= HIST_FIELD_FL_GRAPH; } else { error: hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier)); @@ -2328,6 +2353,8 @@ parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, hist_data->attrs->ts_in_usecs = true; } else if (strcmp(field_name, "common_cpu") == 0) *flags |= HIST_FIELD_FL_CPU; + else if (strcmp(field_name, "hitcount") == 0) + *flags |= HIST_FIELD_FL_HITCOUNT; else { field = trace_find_event_field(file->event_call, field_name); if (!field || !field->size) { @@ -3586,6 +3613,7 @@ static int parse_action_params(struct trace_array *tr, char *params, while (params) { if (data->n_params >= SYNTH_FIELDS_MAX) { hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0); + ret = -EINVAL; goto out; } @@ -3922,6 +3950,10 @@ static int trace_action_create(struct hist_trigger_data *hist_data, lockdep_assert_held(&event_mutex); + /* Sanity check to avoid out-of-bound write on 'data->var_ref_idx' */ + if (data->n_params > SYNTH_FIELDS_MAX) + return -EINVAL; + if (data->use_trace_keyword) synth_event_name = data->synth_event_name; else @@ -4328,8 +4360,8 @@ static int create_var_field(struct hist_trigger_data *hist_data, static int create_val_fields(struct hist_trigger_data *hist_data, struct trace_event_file *file) { + unsigned int i, j = 1, n_hitcount = 0; char *fields_str, *field_str; - unsigned int i, j = 1; int ret; ret = create_hitcount_val(hist_data); @@ -4346,8 +4378,10 @@ static int create_val_fields(struct hist_trigger_data *hist_data, if (!field_str) break; - if (strcmp(field_str, "hitcount") == 0) - continue; + if (strcmp(field_str, "hitcount") == 0) { + if (!n_hitcount++) + continue; + } ret = create_val_field(hist_data, j++, file, field_str); if (ret) @@ -4357,6 +4391,12 @@ static int create_val_fields(struct hist_trigger_data *hist_data, if (fields_str && (strcmp(fields_str, "hitcount") != 0)) ret = -EINVAL; out: + /* There is only raw hitcount but nohitcount suppresses it. */ + if (j == 1 && hist_data->attrs->no_hitcount) { + hist_err(hist_data->event_file->tr, HIST_ERR_NEED_NOHC_VAL, 0); + ret = -ENOENT; + } + return ret; } @@ -5285,33 +5325,101 @@ static void hist_trigger_print_key(struct seq_file *m, seq_puts(m, "}"); } +/* Get the 100 times of the percentage of @val in @total */ +static inline unsigned int __get_percentage(u64 val, u64 total) +{ + if (!total) + goto div0; + + if (val < (U64_MAX / 10000)) + return (unsigned int)div64_ul(val * 10000, total); + + total = div64_u64(total, 10000); + if (!total) + goto div0; + + return (unsigned int)div64_ul(val, total); +div0: + return val ? UINT_MAX : 0; +} + +#define BAR_CHAR '#' + +static inline const char *__fill_bar_str(char *buf, int size, u64 val, u64 max) +{ + unsigned int len = __get_percentage(val, max); + int i; + + if (len == UINT_MAX) { + snprintf(buf, size, "[ERROR]"); + return buf; + } + + len = len * size / 10000; + for (i = 0; i < len && i < size; i++) + buf[i] = BAR_CHAR; + while (i < size) + buf[i++] = ' '; + buf[size] = '\0'; + + return buf; +} + +struct hist_val_stat { + u64 max; + u64 total; +}; + +static void hist_trigger_print_val(struct seq_file *m, unsigned int idx, + const char *field_name, unsigned long flags, + struct hist_val_stat *stats, + struct tracing_map_elt *elt) +{ + u64 val = tracing_map_read_sum(elt, idx); + unsigned int pc; + char bar[21]; + + if (flags & HIST_FIELD_FL_PERCENT) { + pc = __get_percentage(val, stats[idx].total); + if (pc == UINT_MAX) + seq_printf(m, " %s (%%):[ERROR]", field_name); + else + seq_printf(m, " %s (%%): %3u.%02u", field_name, + pc / 100, pc % 100); + } else if (flags & HIST_FIELD_FL_GRAPH) { + seq_printf(m, " %s: %20s", field_name, + __fill_bar_str(bar, 20, val, stats[idx].max)); + } else if (flags & HIST_FIELD_FL_HEX) { + seq_printf(m, " %s: %10llx", field_name, val); + } else { + seq_printf(m, " %s: %10llu", field_name, val); + } +} + static void hist_trigger_entry_print(struct seq_file *m, struct hist_trigger_data *hist_data, + struct hist_val_stat *stats, void *key, struct tracing_map_elt *elt) { const char *field_name; - unsigned int i; + unsigned int i = HITCOUNT_IDX; + unsigned long flags; hist_trigger_print_key(m, hist_data, key, elt); - seq_printf(m, " hitcount: %10llu", - tracing_map_read_sum(elt, HITCOUNT_IDX)); + /* At first, show the raw hitcount if !nohitcount */ + if (!hist_data->attrs->no_hitcount) + hist_trigger_print_val(m, i, "hitcount", 0, stats, elt); for (i = 1; i < hist_data->n_vals; i++) { field_name = hist_field_name(hist_data->fields[i], 0); - - if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR || - hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR) + flags = hist_data->fields[i]->flags; + if (flags & HIST_FIELD_FL_VAR || flags & HIST_FIELD_FL_EXPR) continue; - if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) { - seq_printf(m, " %s: %10llx", field_name, - tracing_map_read_sum(elt, i)); - } else { - seq_printf(m, " %s: %10llu", field_name, - tracing_map_read_sum(elt, i)); - } + seq_puts(m, " "); + hist_trigger_print_val(m, i, field_name, flags, stats, elt); } print_actions(m, hist_data, elt); @@ -5324,7 +5432,9 @@ static int print_entries(struct seq_file *m, { struct tracing_map_sort_entry **sort_entries = NULL; struct tracing_map *map = hist_data->map; - int i, n_entries; + int i, j, n_entries; + struct hist_val_stat *stats = NULL; + u64 val; n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, hist_data->n_sort_keys, @@ -5332,11 +5442,34 @@ static int print_entries(struct seq_file *m, if (n_entries < 0) return n_entries; + /* Calculate the max and the total for each field if needed. */ + for (j = 0; j < hist_data->n_vals; j++) { + if (!(hist_data->fields[j]->flags & + (HIST_FIELD_FL_PERCENT | HIST_FIELD_FL_GRAPH))) + continue; + if (!stats) { + stats = kcalloc(hist_data->n_vals, sizeof(*stats), + GFP_KERNEL); + if (!stats) { + n_entries = -ENOMEM; + goto out; + } + } + for (i = 0; i < n_entries; i++) { + val = tracing_map_read_sum(sort_entries[i]->elt, j); + stats[j].total += val; + if (stats[j].max < val) + stats[j].max = val; + } + } + for (i = 0; i < n_entries; i++) - hist_trigger_entry_print(m, hist_data, + hist_trigger_entry_print(m, hist_data, stats, sort_entries[i]->key, sort_entries[i]->elt); + kfree(stats); +out: tracing_map_destroy_sort_entries(sort_entries, n_entries); return n_entries; @@ -5726,6 +5859,7 @@ static int event_hist_trigger_print(struct seq_file *m, struct hist_trigger_data *hist_data = data->private_data; struct hist_field *field; bool have_var = false; + bool show_val = false; unsigned int i; seq_puts(m, HIST_PREFIX); @@ -5756,12 +5890,16 @@ static int event_hist_trigger_print(struct seq_file *m, continue; } - if (i == HITCOUNT_IDX) + if (i == HITCOUNT_IDX) { + if (hist_data->attrs->no_hitcount) + continue; seq_puts(m, "hitcount"); - else { - seq_puts(m, ","); + } else { + if (show_val) + seq_puts(m, ","); hist_field_print(m, field); } + show_val = true; } if (have_var) { @@ -5812,6 +5950,8 @@ static int event_hist_trigger_print(struct seq_file *m, seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); if (hist_data->enable_timestamps) seq_printf(m, ":clock=%s", hist_data->attrs->clock); + if (hist_data->attrs->no_hitcount) + seq_puts(m, ":nohitcount"); print_actions_spec(m, hist_data); @@ -6438,7 +6578,7 @@ enable: if (se) se->ref++; out: - if (ret == 0) + if (ret == 0 && glob[0]) hist_err_clear(); return ret; diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c index c3b582d19b62..67592eed0be8 100644 --- a/kernel/trace/trace_events_synth.c +++ b/kernel/trace/trace_events_synth.c @@ -1282,12 +1282,12 @@ static int __create_synth_event(const char *name, const char *raw_fields) goto err_free_arg; } - fields[n_fields++] = field; if (n_fields == SYNTH_FIELDS_MAX) { synth_err(SYNTH_ERR_TOO_MANY_FIELDS, 0); ret = -EINVAL; goto err_free_arg; } + fields[n_fields++] = field; n_fields_this_loop++; } diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c index 918730d74932..e535959939d3 100644 --- a/kernel/trace/trace_events_trigger.c +++ b/kernel/trace/trace_events_trigger.c @@ -1067,7 +1067,14 @@ int set_trigger_filter(char *filter_str, /* The filter is for the 'trigger' event, not the triggered event */ ret = create_event_filter(file->tr, file->event_call, - filter_str, false, &filter); + filter_str, true, &filter); + + /* Only enabled set_str for error handling */ + if (filter) { + kfree(filter->filter_string); + filter->filter_string = NULL; + } + /* * If create_event_filter() fails, filter still needs to be freed. * Which the calling code will do with data->filter. @@ -1078,8 +1085,14 @@ int set_trigger_filter(char *filter_str, rcu_assign_pointer(data->filter, filter); if (tmp) { - /* Make sure the call is done with the filter */ - tracepoint_synchronize_unregister(); + /* + * Make sure the call is done with the filter. + * It is possible that a filter could fail at boot up, + * and then this path will be called. Avoid the synchronization + * in that case. + */ + if (system_state != SYSTEM_BOOTING) + tracepoint_synchronize_unregister(); free_event_filter(tmp); } diff --git a/kernel/trace/trace_events_user.c b/kernel/trace/trace_events_user.c index a93ed1c49b08..908e8a13c675 100644 --- a/kernel/trace/trace_events_user.c +++ b/kernel/trace/trace_events_user.c @@ -1359,6 +1359,7 @@ put_user_lock: put_user: user_event_destroy_fields(user); user_event_destroy_validators(user); + kfree(user->call.print_fmt); kfree(user); return ret; } diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 5a75b039e586..ee77c8203bd5 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -1344,7 +1344,6 @@ __kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs, return; fbuffer.regs = regs; - entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event); entry->ip = (unsigned long)tk->rp.kp.addr; store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize); @@ -1385,7 +1384,6 @@ __kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, return; fbuffer.regs = regs; - entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event); entry->func = (unsigned long)tk->rp.kp.addr; entry->ret_ip = get_kretprobe_retaddr(ri); store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize); diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c index 4300c5dc4e5d..210e1f168392 100644 --- a/kernel/trace/trace_osnoise.c +++ b/kernel/trace/trace_osnoise.c @@ -49,6 +49,28 @@ #define DEFAULT_TIMERLAT_PRIO 95 /* FIFO 95 */ /* + * osnoise/options entries. + */ +enum osnoise_options_index { + OSN_DEFAULTS = 0, + OSN_WORKLOAD, + OSN_PANIC_ON_STOP, + OSN_PREEMPT_DISABLE, + OSN_IRQ_DISABLE, + OSN_MAX +}; + +static const char * const osnoise_options_str[OSN_MAX] = { + "DEFAULTS", + "OSNOISE_WORKLOAD", + "PANIC_ON_STOP", + "OSNOISE_PREEMPT_DISABLE", + "OSNOISE_IRQ_DISABLE" }; + +#define OSN_DEFAULT_OPTIONS 0x2 +static unsigned long osnoise_options = OSN_DEFAULT_OPTIONS; + +/* * trace_array of the enabled osnoise/timerlat instances. */ struct osnoise_instance { @@ -125,9 +147,8 @@ static void osnoise_unregister_instance(struct trace_array *tr) * register/unregister serialization is provided by trace's * trace_types_lock. */ - lockdep_assert_held(&trace_types_lock); - - list_for_each_entry_rcu(inst, &osnoise_instances, list) { + list_for_each_entry_rcu(inst, &osnoise_instances, list, + lockdep_is_held(&trace_types_lock)) { if (inst->tr == tr) { list_del_rcu(&inst->list); found = 1; @@ -1173,11 +1194,12 @@ trace_sched_switch_callback(void *data, bool preempt, unsigned int prev_state) { struct osnoise_variables *osn_var = this_cpu_osn_var(); + int workload = test_bit(OSN_WORKLOAD, &osnoise_options); - if (p->pid != osn_var->pid) + if ((p->pid != osn_var->pid) || !workload) thread_exit(osn_var, p); - if (n->pid != osn_var->pid) + if ((n->pid != osn_var->pid) || !workload) thread_entry(osn_var, n); } @@ -1255,6 +1277,9 @@ static __always_inline void osnoise_stop_tracing(void) trace_array_printk_buf(tr->array_buffer.buffer, _THIS_IP_, "stop tracing hit on cpu %d\n", smp_processor_id()); + if (test_bit(OSN_PANIC_ON_STOP, &osnoise_options)) + panic("tracer hit stop condition on CPU %d\n", smp_processor_id()); + tracer_tracing_off(tr); } rcu_read_unlock(); @@ -1289,12 +1314,14 @@ static void notify_new_max_latency(u64 latency) */ static int run_osnoise(void) { + bool disable_irq = test_bit(OSN_IRQ_DISABLE, &osnoise_options); struct osnoise_variables *osn_var = this_cpu_osn_var(); u64 start, sample, last_sample; u64 last_int_count, int_count; s64 noise = 0, max_noise = 0; s64 total, last_total = 0; struct osnoise_sample s; + bool disable_preemption; unsigned int threshold; u64 runtime, stop_in; u64 sum_noise = 0; @@ -1302,6 +1329,12 @@ static int run_osnoise(void) int ret = -1; /* + * Disabling preemption is only required if IRQs are enabled, + * and the options is set on. + */ + disable_preemption = !disable_irq && test_bit(OSN_PREEMPT_DISABLE, &osnoise_options); + + /* * Considers the current thread as the workload. */ osn_var->pid = current->pid; @@ -1317,6 +1350,15 @@ static int run_osnoise(void) threshold = tracing_thresh ? : 5000; /* + * Apply PREEMPT and IRQ disabled options. + */ + if (disable_irq) + local_irq_disable(); + + if (disable_preemption) + preempt_disable(); + + /* * Make sure NMIs see sampling first */ osn_var->sampling = true; @@ -1403,16 +1445,21 @@ static int run_osnoise(void) * cond_resched() */ if (IS_ENABLED(CONFIG_PREEMPT_RCU)) { - local_irq_disable(); + if (!disable_irq) + local_irq_disable(); + rcu_momentary_dyntick_idle(); - local_irq_enable(); + + if (!disable_irq) + local_irq_enable(); } /* * For the non-preemptive kernel config: let threads runs, if - * they so wish. + * they so wish, unless set not do to so. */ - cond_resched(); + if (!disable_irq && !disable_preemption) + cond_resched(); last_sample = sample; last_int_count = int_count; @@ -1432,6 +1479,15 @@ static int run_osnoise(void) barrier(); /* + * Return to the preemptive state. + */ + if (disable_preemption) + preempt_enable(); + + if (disable_irq) + local_irq_enable(); + + /* * Save noise info. */ s.noise = time_to_us(sum_noise); @@ -1710,9 +1766,16 @@ static void stop_kthread(unsigned int cpu) struct task_struct *kthread; kthread = per_cpu(per_cpu_osnoise_var, cpu).kthread; - if (kthread) + if (kthread) { kthread_stop(kthread); - per_cpu(per_cpu_osnoise_var, cpu).kthread = NULL; + per_cpu(per_cpu_osnoise_var, cpu).kthread = NULL; + } else { + if (!test_bit(OSN_WORKLOAD, &osnoise_options)) { + per_cpu(per_cpu_osnoise_var, cpu).sampling = false; + barrier(); + return; + } + } } /* @@ -1746,6 +1809,13 @@ static int start_kthread(unsigned int cpu) snprintf(comm, 24, "timerlat/%d", cpu); main = timerlat_main; } else { + /* if no workload, just return */ + if (!test_bit(OSN_WORKLOAD, &osnoise_options)) { + per_cpu(per_cpu_osnoise_var, cpu).sampling = true; + barrier(); + return 0; + } + snprintf(comm, 24, "osnoise/%d", cpu); } @@ -1861,6 +1931,150 @@ static void osnoise_init_hotplug_support(void) #endif /* CONFIG_HOTPLUG_CPU */ /* + * seq file functions for the osnoise/options file. + */ +static void *s_options_start(struct seq_file *s, loff_t *pos) +{ + int option = *pos; + + mutex_lock(&interface_lock); + + if (option >= OSN_MAX) + return NULL; + + return pos; +} + +static void *s_options_next(struct seq_file *s, void *v, loff_t *pos) +{ + int option = ++(*pos); + + if (option >= OSN_MAX) + return NULL; + + return pos; +} + +static int s_options_show(struct seq_file *s, void *v) +{ + loff_t *pos = v; + int option = *pos; + + if (option == OSN_DEFAULTS) { + if (osnoise_options == OSN_DEFAULT_OPTIONS) + seq_printf(s, "%s", osnoise_options_str[option]); + else + seq_printf(s, "NO_%s", osnoise_options_str[option]); + goto out; + } + + if (test_bit(option, &osnoise_options)) + seq_printf(s, "%s", osnoise_options_str[option]); + else + seq_printf(s, "NO_%s", osnoise_options_str[option]); + +out: + if (option != OSN_MAX) + seq_puts(s, " "); + + return 0; +} + +static void s_options_stop(struct seq_file *s, void *v) +{ + seq_puts(s, "\n"); + mutex_unlock(&interface_lock); +} + +static const struct seq_operations osnoise_options_seq_ops = { + .start = s_options_start, + .next = s_options_next, + .show = s_options_show, + .stop = s_options_stop +}; + +static int osnoise_options_open(struct inode *inode, struct file *file) +{ + return seq_open(file, &osnoise_options_seq_ops); +}; + +/** + * osnoise_options_write - Write function for "options" entry + * @filp: The active open file structure + * @ubuf: The user buffer that contains the value to write + * @cnt: The maximum number of bytes to write to "file" + * @ppos: The current position in @file + * + * Writing the option name sets the option, writing the "NO_" + * prefix in front of the option name disables it. + * + * Writing "DEFAULTS" resets the option values to the default ones. + */ +static ssize_t osnoise_options_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + int running, option, enable, retval; + char buf[256], *option_str; + + if (cnt >= 256) + return -EINVAL; + + if (copy_from_user(buf, ubuf, cnt)) + return -EFAULT; + + buf[cnt] = 0; + + if (strncmp(buf, "NO_", 3)) { + option_str = strstrip(buf); + enable = true; + } else { + option_str = strstrip(&buf[3]); + enable = false; + } + + option = match_string(osnoise_options_str, OSN_MAX, option_str); + if (option < 0) + return -EINVAL; + + /* + * trace_types_lock is taken to avoid concurrency on start/stop. + */ + mutex_lock(&trace_types_lock); + running = osnoise_has_registered_instances(); + if (running) + stop_per_cpu_kthreads(); + + mutex_lock(&interface_lock); + /* + * avoid CPU hotplug operations that might read options. + */ + cpus_read_lock(); + + retval = cnt; + + if (enable) { + if (option == OSN_DEFAULTS) + osnoise_options = OSN_DEFAULT_OPTIONS; + else + set_bit(option, &osnoise_options); + } else { + if (option == OSN_DEFAULTS) + retval = -EINVAL; + else + clear_bit(option, &osnoise_options); + } + + cpus_read_unlock(); + mutex_unlock(&interface_lock); + + if (running) + start_per_cpu_kthreads(); + mutex_unlock(&trace_types_lock); + + return retval; +} + +/* * osnoise_cpus_read - Read function for reading the "cpus" file * @filp: The active open file structure * @ubuf: The userspace provided buffer to read value into @@ -2042,6 +2256,14 @@ static const struct file_operations cpus_fops = { .llseek = generic_file_llseek, }; +static const struct file_operations osnoise_options_fops = { + .open = osnoise_options_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, + .write = osnoise_options_write +}; + #ifdef CONFIG_TIMERLAT_TRACER #ifdef CONFIG_STACKTRACE static int init_timerlat_stack_tracefs(struct dentry *top_dir) @@ -2128,6 +2350,11 @@ static int init_tracefs(void) if (!tmp) goto err; + tmp = trace_create_file("options", TRACE_MODE_WRITE, top_dir, NULL, + &osnoise_options_fops); + if (!tmp) + goto err; + ret = init_timerlat_tracefs(top_dir); if (ret) goto err; diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index 67f47ea27921..bd475a00f96d 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -11,6 +11,7 @@ #include <linux/kprobes.h> #include <linux/sched/clock.h> #include <linux/sched/mm.h> +#include <linux/idr.h> #include "trace_output.h" @@ -21,8 +22,6 @@ DECLARE_RWSEM(trace_event_sem); static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly; -static int next_event_type = __TRACE_LAST_TYPE; - enum print_line_t trace_print_bputs_msg_only(struct trace_iterator *iter) { struct trace_seq *s = &iter->seq; @@ -323,8 +322,9 @@ void trace_event_printf(struct trace_iterator *iter, const char *fmt, ...) } EXPORT_SYMBOL(trace_event_printf); -static int trace_output_raw(struct trace_iterator *iter, char *name, - char *fmt, va_list ap) +static __printf(3, 0) +int trace_output_raw(struct trace_iterator *iter, char *name, + char *fmt, va_list ap) { struct trace_seq *s = &iter->seq; @@ -688,38 +688,23 @@ struct trace_event *ftrace_find_event(int type) return NULL; } -static LIST_HEAD(ftrace_event_list); +static DEFINE_IDA(trace_event_ida); -static int trace_search_list(struct list_head **list) +static void free_trace_event_type(int type) { - struct trace_event *e = NULL, *iter; - int next = __TRACE_LAST_TYPE; - - if (list_empty(&ftrace_event_list)) { - *list = &ftrace_event_list; - return next; - } + if (type >= __TRACE_LAST_TYPE) + ida_free(&trace_event_ida, type); +} - /* - * We used up all possible max events, - * lets see if somebody freed one. - */ - list_for_each_entry(iter, &ftrace_event_list, list) { - if (iter->type != next) { - e = iter; - break; - } - next++; - } +static int alloc_trace_event_type(void) +{ + int next; - /* Did we used up all 65 thousand events??? */ - if (next > TRACE_EVENT_TYPE_MAX) + /* Skip static defined type numbers */ + next = ida_alloc_range(&trace_event_ida, __TRACE_LAST_TYPE, + TRACE_EVENT_TYPE_MAX, GFP_KERNEL); + if (next < 0) return 0; - - if (e) - *list = &e->list; - else - *list = &ftrace_event_list; return next; } @@ -761,28 +746,10 @@ int register_trace_event(struct trace_event *event) if (WARN_ON(!event->funcs)) goto out; - INIT_LIST_HEAD(&event->list); - if (!event->type) { - struct list_head *list = NULL; - - if (next_event_type > TRACE_EVENT_TYPE_MAX) { - - event->type = trace_search_list(&list); - if (!event->type) - goto out; - - } else { - - event->type = next_event_type++; - list = &ftrace_event_list; - } - - if (WARN_ON(ftrace_find_event(event->type))) + event->type = alloc_trace_event_type(); + if (!event->type) goto out; - - list_add_tail(&event->list, list); - } else if (WARN(event->type > __TRACE_LAST_TYPE, "Need to add type to trace.h")) { goto out; @@ -819,7 +786,7 @@ EXPORT_SYMBOL_GPL(register_trace_event); int __unregister_trace_event(struct trace_event *event) { hlist_del(&event->node); - list_del(&event->list); + free_trace_event_type(event->type); return 0; } @@ -1568,7 +1535,7 @@ static struct trace_event *events[] __initdata = { NULL }; -__init static int init_events(void) +__init int init_events(void) { struct trace_event *event; int i, ret; @@ -1581,4 +1548,3 @@ __init static int init_events(void) return 0; } -early_initcall(init_events); diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index 36dff277de46..01ebabbbe8c9 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -76,9 +76,11 @@ const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\""; /* Fetch type information table */ static const struct fetch_type probe_fetch_types[] = { /* Special types */ - __ASSIGN_FETCH_TYPE("string", string, string, sizeof(u32), 1, + __ASSIGN_FETCH_TYPE("string", string, string, sizeof(u32), 1, 1, "__data_loc char[]"), - __ASSIGN_FETCH_TYPE("ustring", string, string, sizeof(u32), 1, + __ASSIGN_FETCH_TYPE("ustring", string, string, sizeof(u32), 1, 1, + "__data_loc char[]"), + __ASSIGN_FETCH_TYPE("symstr", string, string, sizeof(u32), 1, 1, "__data_loc char[]"), /* Basic types */ ASSIGN_FETCH_TYPE(u8, u8, 0), @@ -98,10 +100,15 @@ static const struct fetch_type probe_fetch_types[] = { ASSIGN_FETCH_TYPE_END }; -static const struct fetch_type *find_fetch_type(const char *type) +static const struct fetch_type *find_fetch_type(const char *type, unsigned long flags) { int i; + /* Reject the symbol/symstr for uprobes */ + if (type && (flags & TPARG_FL_USER) && + (!strcmp(type, "symbol") || !strcmp(type, "symstr"))) + return NULL; + if (!type) type = DEFAULT_FETCH_TYPE_STR; @@ -119,13 +126,13 @@ static const struct fetch_type *find_fetch_type(const char *type) switch (bs) { case 8: - return find_fetch_type("u8"); + return find_fetch_type("u8", flags); case 16: - return find_fetch_type("u16"); + return find_fetch_type("u16", flags); case 32: - return find_fetch_type("u32"); + return find_fetch_type("u32", flags); case 64: - return find_fetch_type("u64"); + return find_fetch_type("u64", flags); default: goto fail; } @@ -246,7 +253,7 @@ int traceprobe_parse_event_name(const char **pevent, const char **pgroup, return -EINVAL; } strlcpy(buf, event, slash - event + 1); - if (!is_good_name(buf)) { + if (!is_good_system_name(buf)) { trace_probe_log_err(offset, BAD_GROUP_NAME); return -EINVAL; } @@ -478,7 +485,7 @@ parse_probe_arg(char *arg, const struct fetch_type *type, DEREF_OPEN_BRACE); return -EINVAL; } else { - const struct fetch_type *t2 = find_fetch_type(NULL); + const struct fetch_type *t2 = find_fetch_type(NULL, flags); *tmp = '\0'; ret = parse_probe_arg(arg, t2, &code, end, flags, offs); @@ -630,9 +637,9 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, /* The type of $comm must be "string", and not an array. */ if (parg->count || (t && strcmp(t, "string"))) goto out; - parg->type = find_fetch_type("string"); + parg->type = find_fetch_type("string", flags); } else - parg->type = find_fetch_type(t); + parg->type = find_fetch_type(t, flags); if (!parg->type) { trace_probe_log_err(offset + (t ? (t - arg) : 0), BAD_TYPE); goto out; @@ -662,16 +669,26 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, ret = -EINVAL; /* Store operation */ - if (!strcmp(parg->type->name, "string") || - !strcmp(parg->type->name, "ustring")) { - if (code->op != FETCH_OP_DEREF && code->op != FETCH_OP_UDEREF && - code->op != FETCH_OP_IMM && code->op != FETCH_OP_COMM && - code->op != FETCH_OP_DATA && code->op != FETCH_OP_TP_ARG) { - trace_probe_log_err(offset + (t ? (t - arg) : 0), - BAD_STRING); - goto fail; + if (parg->type->is_string) { + if (!strcmp(parg->type->name, "symstr")) { + if (code->op != FETCH_OP_REG && code->op != FETCH_OP_STACK && + code->op != FETCH_OP_RETVAL && code->op != FETCH_OP_ARG && + code->op != FETCH_OP_DEREF && code->op != FETCH_OP_TP_ARG) { + trace_probe_log_err(offset + (t ? (t - arg) : 0), + BAD_SYMSTRING); + goto fail; + } + } else { + if (code->op != FETCH_OP_DEREF && code->op != FETCH_OP_UDEREF && + code->op != FETCH_OP_IMM && code->op != FETCH_OP_COMM && + code->op != FETCH_OP_DATA && code->op != FETCH_OP_TP_ARG) { + trace_probe_log_err(offset + (t ? (t - arg) : 0), + BAD_STRING); + goto fail; + } } - if ((code->op == FETCH_OP_IMM || code->op == FETCH_OP_COMM || + if (!strcmp(parg->type->name, "symstr") || + (code->op == FETCH_OP_IMM || code->op == FETCH_OP_COMM || code->op == FETCH_OP_DATA) || code->op == FETCH_OP_TP_ARG || parg->count) { /* @@ -679,6 +696,8 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, * must be kept, and if parg->count != 0, this is an * array of string pointers instead of string address * itself. + * For the symstr, it doesn't need to dereference, thus + * it just get the value. */ code++; if (code->op != FETCH_OP_NOP) { @@ -690,6 +709,8 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, if (!strcmp(parg->type->name, "ustring") || code->op == FETCH_OP_UDEREF) code->op = FETCH_OP_ST_USTRING; + else if (!strcmp(parg->type->name, "symstr")) + code->op = FETCH_OP_ST_SYMSTR; else code->op = FETCH_OP_ST_STRING; code->size = parg->type->size; @@ -919,8 +940,7 @@ static int __set_print_fmt(struct trace_probe *tp, char *buf, int len, for (i = 0; i < tp->nr_args; i++) { parg = tp->args + i; if (parg->count) { - if ((strcmp(parg->type->name, "string") == 0) || - (strcmp(parg->type->name, "ustring") == 0)) + if (parg->type->is_string) fmt = ", __get_str(%s[%d])"; else fmt = ", REC->%s[%d]"; @@ -928,8 +948,7 @@ static int __set_print_fmt(struct trace_probe *tp, char *buf, int len, pos += snprintf(buf + pos, LEN_OR_ZERO, fmt, parg->name, j); } else { - if ((strcmp(parg->type->name, "string") == 0) || - (strcmp(parg->type->name, "ustring") == 0)) + if (parg->type->is_string) fmt = ", __get_str(%s)"; else fmt = ", REC->%s"; diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index de38f1c03776..23acfd1c3812 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -98,6 +98,7 @@ enum fetch_op { FETCH_OP_ST_UMEM, /* Mem: .offset, .size */ FETCH_OP_ST_STRING, /* String: .offset, .size */ FETCH_OP_ST_USTRING, /* User String: .offset, .size */ + FETCH_OP_ST_SYMSTR, /* Kernel Symbol String: .offset, .size */ // Stage 4 (modify) op FETCH_OP_MOD_BF, /* Bitfield: .basesize, .lshift, .rshift */ // Stage 5 (loop) op @@ -133,7 +134,8 @@ struct fetch_insn { struct fetch_type { const char *name; /* Name of type */ size_t size; /* Byte size of type */ - int is_signed; /* Signed flag */ + bool is_signed; /* Signed flag */ + bool is_string; /* String flag */ print_type_func_t print; /* Print functions */ const char *fmt; /* Format string */ const char *fmttype; /* Name in format file */ @@ -177,16 +179,19 @@ DECLARE_BASIC_PRINT_TYPE_FUNC(symbol); #define _ADDR_FETCH_TYPE(t) __ADDR_FETCH_TYPE(t) #define ADDR_FETCH_TYPE _ADDR_FETCH_TYPE(BITS_PER_LONG) -#define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \ - {.name = _name, \ +#define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, str, _fmttype) \ + {.name = _name, \ .size = _size, \ - .is_signed = sign, \ + .is_signed = (bool)sign, \ + .is_string = (bool)str, \ .print = PRINT_TYPE_FUNC_NAME(ptype), \ .fmt = PRINT_TYPE_FMT_NAME(ptype), \ .fmttype = _fmttype, \ } + +/* Non string types can use these macros */ #define _ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \ - __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, #_fmttype) + __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, 0, #_fmttype) #define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \ _ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, ptype) @@ -353,7 +358,8 @@ int trace_probe_create(const char *raw_command, int (*createfn)(int, const char #define TPARG_FL_KERNEL BIT(1) #define TPARG_FL_FENTRY BIT(2) #define TPARG_FL_TPOINT BIT(3) -#define TPARG_FL_MASK GENMASK(3, 0) +#define TPARG_FL_USER BIT(4) +#define TPARG_FL_MASK GENMASK(4, 0) extern int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, const char *argv, unsigned int flags); @@ -431,6 +437,7 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call, C(ARRAY_TOO_BIG, "Array number is too big"), \ C(BAD_TYPE, "Unknown type is specified"), \ C(BAD_STRING, "String accepts only memory argument"), \ + C(BAD_SYMSTRING, "Symbol String doesn't accept data/userdata"), \ C(BAD_BITFIELD, "Invalid bitfield"), \ C(ARG_NAME_TOO_LONG, "Argument name is too long"), \ C(NO_ARG_NAME, "Argument name is not specified"), \ diff --git a/kernel/trace/trace_probe_tmpl.h b/kernel/trace/trace_probe_tmpl.h index b3bdb8ddb862..5cea672243f6 100644 --- a/kernel/trace/trace_probe_tmpl.h +++ b/kernel/trace/trace_probe_tmpl.h @@ -67,6 +67,37 @@ probe_mem_read(void *dest, void *src, size_t size); static nokprobe_inline int probe_mem_read_user(void *dest, void *src, size_t size); +static nokprobe_inline int +fetch_store_symstrlen(unsigned long addr) +{ + char namebuf[KSYM_SYMBOL_LEN]; + int ret; + + ret = sprint_symbol(namebuf, addr); + if (ret < 0) + return 0; + + return ret + 1; +} + +/* + * Fetch a null-terminated symbol string + offset. Caller MUST set *(u32 *)buf + * with max length and relative data location. + */ +static nokprobe_inline int +fetch_store_symstring(unsigned long addr, void *dest, void *base) +{ + int maxlen = get_loc_len(*(u32 *)dest); + void *__dest; + + if (unlikely(!maxlen)) + return -ENOMEM; + + __dest = get_loc_data(dest, base); + + return sprint_symbol(__dest, addr); +} + /* From the 2nd stage, routine is same */ static nokprobe_inline int process_fetch_insn_bottom(struct fetch_insn *code, unsigned long val, @@ -99,16 +130,22 @@ stage2: stage3: /* 3rd stage: store value to buffer */ if (unlikely(!dest)) { - if (code->op == FETCH_OP_ST_STRING) { + switch (code->op) { + case FETCH_OP_ST_STRING: ret = fetch_store_strlen(val + code->offset); code++; goto array; - } else if (code->op == FETCH_OP_ST_USTRING) { + case FETCH_OP_ST_USTRING: ret += fetch_store_strlen_user(val + code->offset); code++; goto array; - } else + case FETCH_OP_ST_SYMSTR: + ret += fetch_store_symstrlen(val + code->offset); + code++; + goto array; + default: return -EILSEQ; + } } switch (code->op) { @@ -129,6 +166,10 @@ stage3: loc = *(u32 *)dest; ret = fetch_store_string_user(val + code->offset, dest, base); break; + case FETCH_OP_ST_SYMSTR: + loc = *(u32 *)dest; + ret = fetch_store_symstring(val + code->offset, dest, base); + break; default: return -EILSEQ; } diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c index a2d301f58ced..ff0536cea968 100644 --- a/kernel/trace/trace_selftest.c +++ b/kernel/trace/trace_selftest.c @@ -785,7 +785,14 @@ static struct fgraph_ops fgraph_ops __initdata = { }; #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS -noinline __noclone static void trace_direct_tramp(void) { } +#ifndef CALL_DEPTH_ACCOUNT +#define CALL_DEPTH_ACCOUNT "" +#endif + +noinline __noclone static void trace_direct_tramp(void) +{ + asm(CALL_DEPTH_ACCOUNT); +} #endif /* diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index fb58e86dd117..8d64b6553aed 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -691,7 +691,8 @@ static int __trace_uprobe_create(int argc, const char **argv) for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { trace_probe_log_set_index(i + 2); ret = traceprobe_parse_probe_arg(&tu->tp, i, argv[i], - is_return ? TPARG_FL_RETURN : 0); + (is_return ? TPARG_FL_RETURN : 0) | + TPARG_FL_USER); if (ret) goto error; } diff --git a/kernel/user.c b/kernel/user.c index e2cf8c22b539..d667debeafd6 100644 --- a/kernel/user.c +++ b/kernel/user.c @@ -185,6 +185,7 @@ void free_uid(struct user_struct *up) if (refcount_dec_and_lock_irqsave(&up->__count, &uidhash_lock, &flags)) free_user(up, flags); } +EXPORT_SYMBOL_GPL(free_uid); struct user_struct *alloc_uid(kuid_t uid) { |