From 0263f92fadbb9d294d5971ac57743f882c93b2b3 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Mon, 20 Nov 2023 16:35:59 +0800 Subject: lib/group_cpus.c: avoid acquiring cpu hotplug lock in group_cpus_evenly group_cpus_evenly() could be part of storage driver's error handler, such as nvme driver, when may happen during CPU hotplug, in which storage queue has to drain its pending IOs because all CPUs associated with the queue are offline and the queue is becoming inactive. And handling IO needs error handler to provide forward progress. Then deadlock is caused: 1) inside CPU hotplug handler, CPU hotplug lock is held, and blk-mq's handler is waiting for inflight IO 2) error handler is waiting for CPU hotplug lock 3) inflight IO can't be completed in blk-mq's CPU hotplug handler because error handling can't provide forward progress. Solve the deadlock by not holding CPU hotplug lock in group_cpus_evenly(), in which two stage spreads are taken: 1) the 1st stage is over all present CPUs; 2) the end stage is over all other CPUs. Turns out the two stage spread just needs consistent 'cpu_present_mask', and remove the CPU hotplug lock by storing it into one local cache. This way doesn't change correctness, because all CPUs are still covered. Link: https://lkml.kernel.org/r/20231120083559.285174-1-ming.lei@redhat.com Signed-off-by: Ming Lei Reported-by: Yi Zhang Reported-by: Guangwu Zhang Tested-by: Guangwu Zhang Reviewed-by: Chengming Zhou Reviewed-by: Jens Axboe Cc: Keith Busch Cc: Signed-off-by: Andrew Morton --- lib/group_cpus.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) (limited to 'lib') diff --git a/lib/group_cpus.c b/lib/group_cpus.c index aa3f6815bb12..ee272c4cefcc 100644 --- a/lib/group_cpus.c +++ b/lib/group_cpus.c @@ -366,13 +366,25 @@ struct cpumask *group_cpus_evenly(unsigned int numgrps) if (!masks) goto fail_node_to_cpumask; - /* Stabilize the cpumasks */ - cpus_read_lock(); build_node_to_cpumask(node_to_cpumask); + /* + * Make a local cache of 'cpu_present_mask', so the two stages + * spread can observe consistent 'cpu_present_mask' without holding + * cpu hotplug lock, then we can reduce deadlock risk with cpu + * hotplug code. + * + * Here CPU hotplug may happen when reading `cpu_present_mask`, and + * we can live with the case because it only affects that hotplug + * CPU is handled in the 1st or 2nd stage, and either way is correct + * from API user viewpoint since 2-stage spread is sort of + * optimization. + */ + cpumask_copy(npresmsk, data_race(cpu_present_mask)); + /* grouping present CPUs first */ ret = __group_cpus_evenly(curgrp, numgrps, node_to_cpumask, - cpu_present_mask, nmsk, masks); + npresmsk, nmsk, masks); if (ret < 0) goto fail_build_affinity; nr_present = ret; @@ -387,15 +399,13 @@ struct cpumask *group_cpus_evenly(unsigned int numgrps) curgrp = 0; else curgrp = nr_present; - cpumask_andnot(npresmsk, cpu_possible_mask, cpu_present_mask); + cpumask_andnot(npresmsk, cpu_possible_mask, npresmsk); ret = __group_cpus_evenly(curgrp, numgrps, node_to_cpumask, npresmsk, nmsk, masks); if (ret >= 0) nr_others = ret; fail_build_affinity: - cpus_read_unlock(); - if (ret >= 0) WARN_ON(nr_present + nr_others < numgrps); -- cgit v1.2.3 From ae1914174a63a558113e80d24ccac2773f9f7b2b Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 15 Dec 2023 13:40:57 -0700 Subject: cred: get rid of CONFIG_DEBUG_CREDENTIALS This code is rarely (never?) enabled by distros, and it hasn't caught anything in decades. Let's kill off this legacy debug code. Suggested-by: Linus Torvalds Signed-off-by: Jens Axboe Signed-off-by: Linus Torvalds --- arch/powerpc/configs/skiroot_defconfig | 1 - arch/s390/configs/debug_defconfig | 1 - fs/nfsd/auth.c | 4 - fs/nfsd/nfssvc.c | 1 - fs/nfsd/vfs.c | 9 +- fs/open.c | 3 - include/linux/cred.h | 50 ------- kernel/cred.c | 231 +++--------------------------- kernel/exit.c | 3 - lib/Kconfig.debug | 15 -- net/sunrpc/auth.c | 3 - security/selinux/hooks.c | 6 - tools/objtool/noreturns.h | 1 - tools/testing/selftests/bpf/config.x86_64 | 1 - tools/testing/selftests/hid/config.common | 1 - 15 files changed, 17 insertions(+), 313 deletions(-) (limited to 'lib') diff --git a/arch/powerpc/configs/skiroot_defconfig b/arch/powerpc/configs/skiroot_defconfig index 8d3eacb50d56..9d44e6630908 100644 --- a/arch/powerpc/configs/skiroot_defconfig +++ b/arch/powerpc/configs/skiroot_defconfig @@ -301,7 +301,6 @@ CONFIG_WQ_WATCHDOG=y CONFIG_DEBUG_SG=y CONFIG_DEBUG_NOTIFIERS=y CONFIG_BUG_ON_DATA_CORRUPTION=y -CONFIG_DEBUG_CREDENTIALS=y # CONFIG_FTRACE is not set CONFIG_XMON=y # CONFIG_RUNTIME_TESTING_MENU is not set diff --git a/arch/s390/configs/debug_defconfig b/arch/s390/configs/debug_defconfig index 438cd92e6080..dd0608629310 100644 --- a/arch/s390/configs/debug_defconfig +++ b/arch/s390/configs/debug_defconfig @@ -834,7 +834,6 @@ CONFIG_DEBUG_IRQFLAGS=y CONFIG_DEBUG_LIST=y CONFIG_DEBUG_SG=y CONFIG_DEBUG_NOTIFIERS=y -CONFIG_DEBUG_CREDENTIALS=y CONFIG_RCU_TORTURE_TEST=m CONFIG_RCU_REF_SCALE_TEST=m CONFIG_RCU_CPU_STALL_TIMEOUT=300 diff --git a/fs/nfsd/auth.c b/fs/nfsd/auth.c index fdf2aad73470..e6beaaf4f170 100644 --- a/fs/nfsd/auth.c +++ b/fs/nfsd/auth.c @@ -26,8 +26,6 @@ int nfsd_setuser(struct svc_rqst *rqstp, struct svc_export *exp) int i; int flags = nfsexp_flags(rqstp, exp); - validate_process_creds(); - /* discard any old override before preparing the new set */ revert_creds(get_cred(current_real_cred())); new = prepare_creds(); @@ -81,10 +79,8 @@ int nfsd_setuser(struct svc_rqst *rqstp, struct svc_export *exp) else new->cap_effective = cap_raise_nfsd_set(new->cap_effective, new->cap_permitted); - validate_process_creds(); put_cred(override_creds(new)); put_cred(new); - validate_process_creds(); return 0; oom: diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index fe61d9bbcc1f..5014ab87d313 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -955,7 +955,6 @@ nfsd(void *vrqstp) rqstp->rq_server->sv_maxconn = nn->max_connections; svc_recv(rqstp); - validate_process_creds(); } atomic_dec(&nfsdstats.th_cnt); diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index fbbea7498f02..e01e4e2acbd9 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -901,7 +901,6 @@ nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type, int host_err; bool retried = false; - validate_process_creds(); /* * If we get here, then the client has already done an "open", * and (hopefully) checked permission - so allow OWNER_OVERRIDE @@ -926,7 +925,6 @@ retry: } err = nfserrno(host_err); } - validate_process_creds(); return err; } @@ -943,12 +941,7 @@ int nfsd_open_verified(struct svc_rqst *rqstp, struct svc_fh *fhp, int may_flags, struct file **filp) { - int err; - - validate_process_creds(); - err = __nfsd_open(rqstp, fhp, S_IFREG, may_flags, filp); - validate_process_creds(); - return err; + return __nfsd_open(rqstp, fhp, S_IFREG, may_flags, filp); } /* diff --git a/fs/open.c b/fs/open.c index 02dc608d40d8..3494a9cd8046 100644 --- a/fs/open.c +++ b/fs/open.c @@ -1088,8 +1088,6 @@ struct file *dentry_open(const struct path *path, int flags, int error; struct file *f; - validate_creds(cred); - /* We must always pass in a valid mount pointer. */ BUG_ON(!path->mnt); @@ -1128,7 +1126,6 @@ struct file *dentry_create(const struct path *path, int flags, umode_t mode, struct file *f; int error; - validate_creds(cred); f = alloc_empty_file(flags, cred); if (IS_ERR(f)) return f; diff --git a/include/linux/cred.h b/include/linux/cred.h index a3383f8efb8f..2976f534a7a3 100644 --- a/include/linux/cred.h +++ b/include/linux/cred.h @@ -110,13 +110,6 @@ static inline int groups_search(const struct group_info *group_info, kgid_t grp) */ struct cred { atomic_long_t usage; -#ifdef CONFIG_DEBUG_CREDENTIALS - atomic_t subscribers; /* number of processes subscribed */ - void *put_addr; - unsigned magic; -#define CRED_MAGIC 0x43736564 -#define CRED_MAGIC_DEAD 0x44656144 -#endif kuid_t uid; /* real UID of the task */ kgid_t gid; /* real GID of the task */ kuid_t suid; /* saved UID of the task */ @@ -172,46 +165,6 @@ extern int cred_fscmp(const struct cred *, const struct cred *); extern void __init cred_init(void); extern int set_cred_ucounts(struct cred *); -/* - * check for validity of credentials - */ -#ifdef CONFIG_DEBUG_CREDENTIALS -extern void __noreturn __invalid_creds(const struct cred *, const char *, unsigned); -extern void __validate_process_creds(struct task_struct *, - const char *, unsigned); - -extern bool creds_are_invalid(const struct cred *cred); - -static inline void __validate_creds(const struct cred *cred, - const char *file, unsigned line) -{ - if (unlikely(creds_are_invalid(cred))) - __invalid_creds(cred, file, line); -} - -#define validate_creds(cred) \ -do { \ - __validate_creds((cred), __FILE__, __LINE__); \ -} while(0) - -#define validate_process_creds() \ -do { \ - __validate_process_creds(current, __FILE__, __LINE__); \ -} while(0) - -extern void validate_creds_for_do_exit(struct task_struct *); -#else -static inline void validate_creds(const struct cred *cred) -{ -} -static inline void validate_creds_for_do_exit(struct task_struct *tsk) -{ -} -static inline void validate_process_creds(void) -{ -} -#endif - static inline bool cap_ambient_invariant_ok(const struct cred *cred) { return cap_issubset(cred->cap_ambient, @@ -264,7 +217,6 @@ static inline const struct cred *get_cred_many(const struct cred *cred, int nr) struct cred *nonconst_cred = (struct cred *) cred; if (!cred) return cred; - validate_creds(cred); nonconst_cred->non_rcu = 0; return get_new_cred_many(nonconst_cred, nr); } @@ -290,7 +242,6 @@ static inline const struct cred *get_cred_rcu(const struct cred *cred) return NULL; if (!atomic_long_inc_not_zero(&nonconst_cred->usage)) return NULL; - validate_creds(cred); nonconst_cred->non_rcu = 0; return cred; } @@ -312,7 +263,6 @@ static inline void put_cred_many(const struct cred *_cred, int nr) struct cred *cred = (struct cred *) _cred; if (cred) { - validate_creds(cred); if (atomic_long_sub_and_test(nr, &cred->usage)) __put_cred(cred); } diff --git a/kernel/cred.c b/kernel/cred.c index 4a6cd0f0fef5..c033a201c808 100644 --- a/kernel/cred.c +++ b/kernel/cred.c @@ -43,10 +43,6 @@ static struct group_info init_groups = { .usage = REFCOUNT_INIT(2) }; */ struct cred init_cred = { .usage = ATOMIC_INIT(4), -#ifdef CONFIG_DEBUG_CREDENTIALS - .subscribers = ATOMIC_INIT(2), - .magic = CRED_MAGIC, -#endif .uid = GLOBAL_ROOT_UID, .gid = GLOBAL_ROOT_GID, .suid = GLOBAL_ROOT_UID, @@ -66,31 +62,6 @@ struct cred init_cred = { .ucounts = &init_ucounts, }; -static inline void set_cred_subscribers(struct cred *cred, int n) -{ -#ifdef CONFIG_DEBUG_CREDENTIALS - atomic_set(&cred->subscribers, n); -#endif -} - -static inline int read_cred_subscribers(const struct cred *cred) -{ -#ifdef CONFIG_DEBUG_CREDENTIALS - return atomic_read(&cred->subscribers); -#else - return 0; -#endif -} - -static inline void alter_cred_subscribers(const struct cred *_cred, int n) -{ -#ifdef CONFIG_DEBUG_CREDENTIALS - struct cred *cred = (struct cred *) _cred; - - atomic_add(n, &cred->subscribers); -#endif -} - /* * The RCU callback to actually dispose of a set of credentials */ @@ -100,20 +71,9 @@ static void put_cred_rcu(struct rcu_head *rcu) kdebug("put_cred_rcu(%p)", cred); -#ifdef CONFIG_DEBUG_CREDENTIALS - if (cred->magic != CRED_MAGIC_DEAD || - atomic_long_read(&cred->usage) != 0 || - read_cred_subscribers(cred) != 0) - panic("CRED: put_cred_rcu() sees %p with" - " mag %x, put %p, usage %ld, subscr %d\n", - cred, cred->magic, cred->put_addr, - atomic_long_read(&cred->usage), - read_cred_subscribers(cred)); -#else if (atomic_long_read(&cred->usage) != 0) panic("CRED: put_cred_rcu() sees %p with usage %ld\n", cred, atomic_long_read(&cred->usage)); -#endif security_cred_free(cred); key_put(cred->session_keyring); @@ -137,16 +97,10 @@ static void put_cred_rcu(struct rcu_head *rcu) */ void __put_cred(struct cred *cred) { - kdebug("__put_cred(%p{%ld,%d})", cred, - atomic_long_read(&cred->usage), - read_cred_subscribers(cred)); + kdebug("__put_cred(%p{%ld})", cred, + atomic_long_read(&cred->usage)); BUG_ON(atomic_long_read(&cred->usage) != 0); -#ifdef CONFIG_DEBUG_CREDENTIALS - BUG_ON(read_cred_subscribers(cred) != 0); - cred->magic = CRED_MAGIC_DEAD; - cred->put_addr = __builtin_return_address(0); -#endif BUG_ON(cred == current->cred); BUG_ON(cred == current->real_cred); @@ -164,9 +118,8 @@ void exit_creds(struct task_struct *tsk) { struct cred *real_cred, *cred; - kdebug("exit_creds(%u,%p,%p,{%ld,%d})", tsk->pid, tsk->real_cred, tsk->cred, - atomic_long_read(&tsk->cred->usage), - read_cred_subscribers(tsk->cred)); + kdebug("exit_creds(%u,%p,%p,{%ld})", tsk->pid, tsk->real_cred, tsk->cred, + atomic_long_read(&tsk->cred->usage)); real_cred = (struct cred *) tsk->real_cred; tsk->real_cred = NULL; @@ -174,15 +127,10 @@ void exit_creds(struct task_struct *tsk) cred = (struct cred *) tsk->cred; tsk->cred = NULL; - validate_creds(cred); if (real_cred == cred) { - alter_cred_subscribers(cred, -2); put_cred_many(cred, 2); } else { - validate_creds(real_cred); - alter_cred_subscribers(real_cred, -1); put_cred(real_cred); - alter_cred_subscribers(cred, -1); put_cred(cred); } @@ -231,9 +179,6 @@ struct cred *cred_alloc_blank(void) return NULL; atomic_long_set(&new->usage, 1); -#ifdef CONFIG_DEBUG_CREDENTIALS - new->magic = CRED_MAGIC; -#endif if (security_cred_alloc_blank(new, GFP_KERNEL_ACCOUNT) < 0) goto error; @@ -264,8 +209,6 @@ struct cred *prepare_creds(void) const struct cred *old; struct cred *new; - validate_process_creds(); - new = kmem_cache_alloc(cred_jar, GFP_KERNEL); if (!new) return NULL; @@ -277,7 +220,6 @@ struct cred *prepare_creds(void) new->non_rcu = 0; atomic_long_set(&new->usage, 1); - set_cred_subscribers(new, 0); get_group_info(new->group_info); get_uid(new->user); get_user_ns(new->user_ns); @@ -300,7 +242,6 @@ struct cred *prepare_creds(void) if (security_prepare_creds(new, old, GFP_KERNEL_ACCOUNT) < 0) goto error; - validate_creds(new); return new; error: @@ -362,10 +303,8 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags) clone_flags & CLONE_THREAD ) { p->real_cred = get_cred_many(p->cred, 2); - alter_cred_subscribers(p->cred, 2); - kdebug("share_creds(%p{%ld,%d})", - p->cred, atomic_long_read(&p->cred->usage), - read_cred_subscribers(p->cred)); + kdebug("share_creds(%p{%ld})", + p->cred, atomic_long_read(&p->cred->usage)); inc_rlimit_ucounts(task_ucounts(p), UCOUNT_RLIMIT_NPROC, 1); return 0; } @@ -404,8 +343,6 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags) p->cred = p->real_cred = get_cred(new); inc_rlimit_ucounts(task_ucounts(p), UCOUNT_RLIMIT_NPROC, 1); - alter_cred_subscribers(new, 2); - validate_creds(new); return 0; error_put: @@ -457,16 +394,10 @@ int commit_creds(struct cred *new) struct task_struct *task = current; const struct cred *old = task->real_cred; - kdebug("commit_creds(%p{%ld,%d})", new, - atomic_long_read(&new->usage), - read_cred_subscribers(new)); + kdebug("commit_creds(%p{%ld})", new, + atomic_long_read(&new->usage)); BUG_ON(task->cred != old); -#ifdef CONFIG_DEBUG_CREDENTIALS - BUG_ON(read_cred_subscribers(old) < 2); - validate_creds(old); - validate_creds(new); -#endif BUG_ON(atomic_long_read(&new->usage) < 1); get_cred(new); /* we will require a ref for the subj creds too */ @@ -502,14 +433,12 @@ int commit_creds(struct cred *new) * RLIMIT_NPROC limits on user->processes have already been checked * in set_user(). */ - alter_cred_subscribers(new, 2); if (new->user != old->user || new->user_ns != old->user_ns) inc_rlimit_ucounts(new->ucounts, UCOUNT_RLIMIT_NPROC, 1); rcu_assign_pointer(task->real_cred, new); rcu_assign_pointer(task->cred, new); if (new->user != old->user || new->user_ns != old->user_ns) dec_rlimit_ucounts(old->ucounts, UCOUNT_RLIMIT_NPROC, 1); - alter_cred_subscribers(old, -2); /* send notifications */ if (!uid_eq(new->uid, old->uid) || @@ -539,13 +468,9 @@ EXPORT_SYMBOL(commit_creds); */ void abort_creds(struct cred *new) { - kdebug("abort_creds(%p{%ld,%d})", new, - atomic_long_read(&new->usage), - read_cred_subscribers(new)); + kdebug("abort_creds(%p{%ld})", new, + atomic_long_read(&new->usage)); -#ifdef CONFIG_DEBUG_CREDENTIALS - BUG_ON(read_cred_subscribers(new) != 0); -#endif BUG_ON(atomic_long_read(&new->usage) < 1); put_cred(new); } @@ -562,12 +487,8 @@ const struct cred *override_creds(const struct cred *new) { const struct cred *old = current->cred; - kdebug("override_creds(%p{%ld,%d})", new, - atomic_long_read(&new->usage), - read_cred_subscribers(new)); - - validate_creds(old); - validate_creds(new); + kdebug("override_creds(%p{%ld})", new, + atomic_long_read(&new->usage)); /* * NOTE! This uses 'get_new_cred()' rather than 'get_cred()'. @@ -576,18 +497,12 @@ const struct cred *override_creds(const struct cred *new) * we are only installing the cred into the thread-synchronous * '->cred' pointer, not the '->real_cred' pointer that is * visible to other threads under RCU. - * - * Also note that we did validate_creds() manually, not depending - * on the validation in 'get_cred()'. */ get_new_cred((struct cred *)new); - alter_cred_subscribers(new, 1); rcu_assign_pointer(current->cred, new); - alter_cred_subscribers(old, -1); - kdebug("override_creds() = %p{%ld,%d}", old, - atomic_long_read(&old->usage), - read_cred_subscribers(old)); + kdebug("override_creds() = %p{%ld}", old, + atomic_long_read(&old->usage)); return old; } EXPORT_SYMBOL(override_creds); @@ -603,15 +518,10 @@ void revert_creds(const struct cred *old) { const struct cred *override = current->cred; - kdebug("revert_creds(%p{%ld,%d})", old, - atomic_long_read(&old->usage), - read_cred_subscribers(old)); + kdebug("revert_creds(%p{%ld})", old, + atomic_long_read(&old->usage)); - validate_creds(old); - validate_creds(override); - alter_cred_subscribers(old, 1); rcu_assign_pointer(current->cred, old); - alter_cred_subscribers(override, -1); put_cred(override); } EXPORT_SYMBOL(revert_creds); @@ -731,12 +641,10 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon) kdebug("prepare_kernel_cred() alloc %p", new); old = get_task_cred(daemon); - validate_creds(old); *new = *old; new->non_rcu = 0; atomic_long_set(&new->usage, 1); - set_cred_subscribers(new, 0); get_uid(new->user); get_user_ns(new->user_ns); get_group_info(new->group_info); @@ -760,7 +668,6 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon) goto error; put_cred(old); - validate_creds(new); return new; error: @@ -825,109 +732,3 @@ int set_create_files_as(struct cred *new, struct inode *inode) return security_kernel_create_files_as(new, inode); } EXPORT_SYMBOL(set_create_files_as); - -#ifdef CONFIG_DEBUG_CREDENTIALS - -bool creds_are_invalid(const struct cred *cred) -{ - if (cred->magic != CRED_MAGIC) - return true; - return false; -} -EXPORT_SYMBOL(creds_are_invalid); - -/* - * dump invalid credentials - */ -static void dump_invalid_creds(const struct cred *cred, const char *label, - const struct task_struct *tsk) -{ - pr_err("%s credentials: %p %s%s%s\n", - label, cred, - cred == &init_cred ? "[init]" : "", - cred == tsk->real_cred ? "[real]" : "", - cred == tsk->cred ? "[eff]" : ""); - pr_err("->magic=%x, put_addr=%p\n", - cred->magic, cred->put_addr); - pr_err("->usage=%ld, subscr=%d\n", - atomic_long_read(&cred->usage), - read_cred_subscribers(cred)); - pr_err("->*uid = { %d,%d,%d,%d }\n", - from_kuid_munged(&init_user_ns, cred->uid), - from_kuid_munged(&init_user_ns, cred->euid), - from_kuid_munged(&init_user_ns, cred->suid), - from_kuid_munged(&init_user_ns, cred->fsuid)); - pr_err("->*gid = { %d,%d,%d,%d }\n", - from_kgid_munged(&init_user_ns, cred->gid), - from_kgid_munged(&init_user_ns, cred->egid), - from_kgid_munged(&init_user_ns, cred->sgid), - from_kgid_munged(&init_user_ns, cred->fsgid)); -#ifdef CONFIG_SECURITY - pr_err("->security is %p\n", cred->security); - if ((unsigned long) cred->security >= PAGE_SIZE && - (((unsigned long) cred->security & 0xffffff00) != - (POISON_FREE << 24 | POISON_FREE << 16 | POISON_FREE << 8))) - pr_err("->security {%x, %x}\n", - ((u32*)cred->security)[0], - ((u32*)cred->security)[1]); -#endif -} - -/* - * report use of invalid credentials - */ -void __noreturn __invalid_creds(const struct cred *cred, const char *file, unsigned line) -{ - pr_err("Invalid credentials\n"); - pr_err("At %s:%u\n", file, line); - dump_invalid_creds(cred, "Specified", current); - BUG(); -} -EXPORT_SYMBOL(__invalid_creds); - -/* - * check the credentials on a process - */ -void __validate_process_creds(struct task_struct *tsk, - const char *file, unsigned line) -{ - if (tsk->cred == tsk->real_cred) { - if (unlikely(read_cred_subscribers(tsk->cred) < 2 || - creds_are_invalid(tsk->cred))) - goto invalid_creds; - } else { - if (unlikely(read_cred_subscribers(tsk->real_cred) < 1 || - read_cred_subscribers(tsk->cred) < 1 || - creds_are_invalid(tsk->real_cred) || - creds_are_invalid(tsk->cred))) - goto invalid_creds; - } - return; - -invalid_creds: - pr_err("Invalid process credentials\n"); - pr_err("At %s:%u\n", file, line); - - dump_invalid_creds(tsk->real_cred, "Real", tsk); - if (tsk->cred != tsk->real_cred) - dump_invalid_creds(tsk->cred, "Effective", tsk); - else - pr_err("Effective creds == Real creds\n"); - BUG(); -} -EXPORT_SYMBOL(__validate_process_creds); - -/* - * check creds for do_exit() - */ -void validate_creds_for_do_exit(struct task_struct *tsk) -{ - kdebug("validate_creds_for_do_exit(%p,%p{%ld,%d})", - tsk->real_cred, tsk->cred, - atomic_long_read(&tsk->cred->usage), - read_cred_subscribers(tsk->cred)); - - __validate_process_creds(tsk, __FILE__, __LINE__); -} - -#endif /* CONFIG_DEBUG_CREDENTIALS */ diff --git a/kernel/exit.c b/kernel/exit.c index ee9f43bed49a..aedc0832c9f4 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -824,8 +824,6 @@ void __noreturn do_exit(long code) ptrace_event(PTRACE_EVENT_EXIT, code); user_events_exit(tsk); - validate_creds_for_do_exit(tsk); - io_uring_files_cancel(); exit_signals(tsk); /* sets PF_EXITING */ @@ -909,7 +907,6 @@ void __noreturn do_exit(long code) if (tsk->task_frag.page) put_page(tsk->task_frag.page); - validate_creds_for_do_exit(tsk); exit_task_stack_account(tsk); check_stack_usage(); diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index cc7d53d9dc01..4405f81248fb 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1739,21 +1739,6 @@ config DEBUG_MAPLE_TREE endmenu -config DEBUG_CREDENTIALS - bool "Debug credential management" - depends on DEBUG_KERNEL - help - Enable this to turn on some debug checking for credential - management. The additional code keeps track of the number of - pointers from task_structs to any given cred struct, and checks to - see that this number never exceeds the usage count of the cred - struct. - - Furthermore, if SELinux is enabled, this also checks that the - security pointer in the cred struct is never seen to be invalid. - - If unsure, say N. - source "kernel/rcu/Kconfig.debug" config DEBUG_WQ_FORCE_RR_CPU diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c index 7bfe7d9a32aa..04534ea537c8 100644 --- a/net/sunrpc/auth.c +++ b/net/sunrpc/auth.c @@ -40,9 +40,6 @@ static unsigned long number_cred_unused; static struct cred machine_cred = { .usage = ATOMIC_INIT(1), -#ifdef CONFIG_DEBUG_CREDENTIALS - .magic = CRED_MAGIC, -#endif }; /* diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index feda711c6b7b..340b2bbbb2dd 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1660,8 +1660,6 @@ static int inode_has_perm(const struct cred *cred, struct inode_security_struct *isec; u32 sid; - validate_creds(cred); - if (unlikely(IS_PRIVATE(inode))) return 0; @@ -3056,8 +3054,6 @@ static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, struct inode_security_struct *isec; u32 sid; - validate_creds(cred); - ad.type = LSM_AUDIT_DATA_DENTRY; ad.u.dentry = dentry; sid = cred_sid(cred); @@ -3101,8 +3097,6 @@ static int selinux_inode_permission(struct inode *inode, int mask) if (!mask) return 0; - validate_creds(cred); - if (unlikely(IS_PRIVATE(inode))) return 0; diff --git a/tools/objtool/noreturns.h b/tools/objtool/noreturns.h index 649ebdef9c3f..1685d7ea6a9f 100644 --- a/tools/objtool/noreturns.h +++ b/tools/objtool/noreturns.h @@ -6,7 +6,6 @@ * * Yes, this is unfortunate. A better solution is in the works. */ -NORETURN(__invalid_creds) NORETURN(__kunit_abort) NORETURN(__module_put_and_kthread_exit) NORETURN(__reiserfs_panic) diff --git a/tools/testing/selftests/bpf/config.x86_64 b/tools/testing/selftests/bpf/config.x86_64 index 2e70a6048278..49a29dbc1910 100644 --- a/tools/testing/selftests/bpf/config.x86_64 +++ b/tools/testing/selftests/bpf/config.x86_64 @@ -50,7 +50,6 @@ CONFIG_CRYPTO_SEQIV=y CONFIG_CRYPTO_XXHASH=y CONFIG_DCB=y CONFIG_DEBUG_ATOMIC_SLEEP=y -CONFIG_DEBUG_CREDENTIALS=y CONFIG_DEBUG_INFO_BTF=y CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y CONFIG_DEBUG_MEMORY_INIT=y diff --git a/tools/testing/selftests/hid/config.common b/tools/testing/selftests/hid/config.common index 0617275d93cc..0f456dbab62f 100644 --- a/tools/testing/selftests/hid/config.common +++ b/tools/testing/selftests/hid/config.common @@ -46,7 +46,6 @@ CONFIG_CRYPTO_SEQIV=y CONFIG_CRYPTO_XXHASH=y CONFIG_DCB=y CONFIG_DEBUG_ATOMIC_SLEEP=y -CONFIG_DEBUG_CREDENTIALS=y CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y CONFIG_DEBUG_MEMORY_INIT=y CONFIG_DEFAULT_FQ_CODEL=y -- cgit v1.2.3 From 60e43fe5285e2077ce9904d78cd42a230d03b788 Mon Sep 17 00:00:00 2001 From: Dave Jiang Date: Thu, 21 Dec 2023 15:02:31 -0700 Subject: lib/firmware_table: tables: Add CDAT table parsing support The CDAT table is very similar to ACPI tables when it comes to sub-table and entry structures. The helper functions can be also used to parse the CDAT table. Add support to the helper functions to deal with an external CDAT table, and also handle the endieness since CDAT can be processed by a BE host. Export a function cdat_table_parse() for CXL driver to parse a CDAT table. In order to minimize ACPICA code changes, __force is being utilized to deal with the case of a big endian (BE) host parsing a CDAT. All CDAT data structure variables are being force casted to __leX as appropriate. Cc: Rafael J. Wysocki Cc: Len Brown Reviewed-by: Jonathan Cameron Signed-off-by: Dave Jiang Acked-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/170319615131.2212653.10932785667981494238.stgit@djiang5-mobl3 Signed-off-by: Dan Williams --- drivers/acpi/tables.c | 5 ++-- include/linux/fw_table.h | 21 +++++++++++++- lib/fw_table.c | 75 ++++++++++++++++++++++++++++++++++++++++-------- 3 files changed, 86 insertions(+), 15 deletions(-) (limited to 'lib') diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c index c1516337f668..b07f7d091d13 100644 --- a/drivers/acpi/tables.c +++ b/drivers/acpi/tables.c @@ -251,8 +251,9 @@ int __init_or_acpilib acpi_table_parse_entries_array( return -ENODEV; } - count = acpi_parse_entries_array(id, table_size, table_header, - proc, proc_num, max_entries); + count = acpi_parse_entries_array(id, table_size, + (union fw_table_header *)table_header, + proc, proc_num, max_entries); acpi_put_table(table_header); return count; diff --git a/include/linux/fw_table.h b/include/linux/fw_table.h index ca49947f0a77..95421860397a 100644 --- a/include/linux/fw_table.h +++ b/include/linux/fw_table.h @@ -25,16 +25,35 @@ struct acpi_subtable_proc { int count; }; +union fw_table_header { + struct acpi_table_header acpi; + struct acpi_table_cdat cdat; +}; + union acpi_subtable_headers { struct acpi_subtable_header common; struct acpi_hmat_structure hmat; struct acpi_prmt_module_header prmt; struct acpi_cedt_header cedt; + struct acpi_cdat_header cdat; }; int acpi_parse_entries_array(char *id, unsigned long table_size, - struct acpi_table_header *table_header, + union fw_table_header *table_header, struct acpi_subtable_proc *proc, int proc_num, unsigned int max_entries); +int cdat_table_parse(enum acpi_cdat_type type, + acpi_tbl_entry_handler_arg handler_arg, void *arg, + struct acpi_table_cdat *table_header); + +/* CXL is the only non-ACPI consumer of the FIRMWARE_TABLE library */ +#if IS_ENABLED(CONFIG_ACPI) && !IS_ENABLED(CONFIG_CXL_BUS) +#define EXPORT_SYMBOL_FWTBL_LIB(x) EXPORT_SYMBOL_ACPI_LIB(x) +#define __init_or_fwtbl_lib __init_or_acpilib +#else +#define EXPORT_SYMBOL_FWTBL_LIB(x) EXPORT_SYMBOL_NS_GPL(x, CXL) +#define __init_or_fwtbl_lib +#endif + #endif diff --git a/lib/fw_table.c b/lib/fw_table.c index 294df54e33b6..1e5e0b2f7012 100644 --- a/lib/fw_table.c +++ b/lib/fw_table.c @@ -12,12 +12,14 @@ #include #include #include +#include enum acpi_subtable_type { ACPI_SUBTABLE_COMMON, ACPI_SUBTABLE_HMAT, ACPI_SUBTABLE_PRMT, ACPI_SUBTABLE_CEDT, + CDAT_SUBTABLE, }; struct acpi_subtable_entry { @@ -25,7 +27,7 @@ struct acpi_subtable_entry { enum acpi_subtable_type type; }; -static unsigned long __init_or_acpilib +static unsigned long __init_or_fwtbl_lib acpi_get_entry_type(struct acpi_subtable_entry *entry) { switch (entry->type) { @@ -37,11 +39,13 @@ acpi_get_entry_type(struct acpi_subtable_entry *entry) return 0; case ACPI_SUBTABLE_CEDT: return entry->hdr->cedt.type; + case CDAT_SUBTABLE: + return entry->hdr->cdat.type; } return 0; } -static unsigned long __init_or_acpilib +static unsigned long __init_or_fwtbl_lib acpi_get_entry_length(struct acpi_subtable_entry *entry) { switch (entry->type) { @@ -53,11 +57,16 @@ acpi_get_entry_length(struct acpi_subtable_entry *entry) return entry->hdr->prmt.length; case ACPI_SUBTABLE_CEDT: return entry->hdr->cedt.length; + case CDAT_SUBTABLE: { + __le16 length = (__force __le16)entry->hdr->cdat.length; + + return le16_to_cpu(length); + } } return 0; } -static unsigned long __init_or_acpilib +static unsigned long __init_or_fwtbl_lib acpi_get_subtable_header_length(struct acpi_subtable_entry *entry) { switch (entry->type) { @@ -69,11 +78,13 @@ acpi_get_subtable_header_length(struct acpi_subtable_entry *entry) return sizeof(entry->hdr->prmt); case ACPI_SUBTABLE_CEDT: return sizeof(entry->hdr->cedt); + case CDAT_SUBTABLE: + return sizeof(entry->hdr->cdat); } return 0; } -static enum acpi_subtable_type __init_or_acpilib +static enum acpi_subtable_type __init_or_fwtbl_lib acpi_get_subtable_type(char *id) { if (strncmp(id, ACPI_SIG_HMAT, 4) == 0) @@ -82,17 +93,32 @@ acpi_get_subtable_type(char *id) return ACPI_SUBTABLE_PRMT; if (strncmp(id, ACPI_SIG_CEDT, 4) == 0) return ACPI_SUBTABLE_CEDT; + if (strncmp(id, ACPI_SIG_CDAT, 4) == 0) + return CDAT_SUBTABLE; return ACPI_SUBTABLE_COMMON; } -static __init_or_acpilib bool has_handler(struct acpi_subtable_proc *proc) +static unsigned long __init_or_fwtbl_lib +acpi_table_get_length(enum acpi_subtable_type type, + union fw_table_header *header) +{ + if (type == CDAT_SUBTABLE) { + __le32 length = (__force __le32)header->cdat.length; + + return le32_to_cpu(length); + } + + return header->acpi.length; +} + +static __init_or_fwtbl_lib bool has_handler(struct acpi_subtable_proc *proc) { return proc->handler || proc->handler_arg; } -static __init_or_acpilib int call_handler(struct acpi_subtable_proc *proc, - union acpi_subtable_headers *hdr, - unsigned long end) +static __init_or_fwtbl_lib int call_handler(struct acpi_subtable_proc *proc, + union acpi_subtable_headers *hdr, + unsigned long end) { if (proc->handler) return proc->handler(hdr, end); @@ -124,23 +150,26 @@ static __init_or_acpilib int call_handler(struct acpi_subtable_proc *proc, * On success returns sum of all matching entries for all proc handlers. * Otherwise, -ENODEV or -EINVAL is returned. */ -int __init_or_acpilib +int __init_or_fwtbl_lib acpi_parse_entries_array(char *id, unsigned long table_size, - struct acpi_table_header *table_header, + union fw_table_header *table_header, struct acpi_subtable_proc *proc, int proc_num, unsigned int max_entries) { unsigned long table_end, subtable_len, entry_len; struct acpi_subtable_entry entry; + enum acpi_subtable_type type; int count = 0; int errs = 0; int i; - table_end = (unsigned long)table_header + table_header->length; + type = acpi_get_subtable_type(id); + table_end = (unsigned long)table_header + + acpi_table_get_length(type, table_header); /* Parse all entries looking for a match. */ - entry.type = acpi_get_subtable_type(id); + entry.type = type; entry.hdr = (union acpi_subtable_headers *) ((unsigned long)table_header + table_size); subtable_len = acpi_get_subtable_header_length(&entry); @@ -186,3 +215,25 @@ acpi_parse_entries_array(char *id, unsigned long table_size, return errs ? -EINVAL : count; } + +int __init_or_fwtbl_lib +cdat_table_parse(enum acpi_cdat_type type, + acpi_tbl_entry_handler_arg handler_arg, + void *arg, + struct acpi_table_cdat *table_header) +{ + struct acpi_subtable_proc proc = { + .id = type, + .handler_arg = handler_arg, + .arg = arg, + }; + + if (!table_header) + return -EINVAL; + + return acpi_parse_entries_array(ACPI_SIG_CDAT, + sizeof(struct acpi_table_cdat), + (union fw_table_header *)table_header, + &proc, 1, 0); +} +EXPORT_SYMBOL_FWTBL_LIB(cdat_table_parse); -- cgit v1.2.3