diff options
| -rw-r--r-- | arch/x86/net/bpf_jit_comp.c | 6 | ||||
| -rw-r--r-- | include/linux/bpf.h | 8 | ||||
| -rw-r--r-- | kernel/bpf/arraymap.c | 80 | ||||
| -rw-r--r-- | kernel/bpf/core.c | 2 | ||||
| -rw-r--r-- | kernel/bpf/syscall.c | 2 |
5 files changed, 60 insertions, 38 deletions
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index ec5214f39aa8..70efcd0940f9 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -246,7 +246,7 @@ static void emit_prologue(u8 **pprog) * goto out; * if (++tail_call_cnt > MAX_TAIL_CALL_CNT) * goto out; - * prog = array->prog[index]; + * prog = array->ptrs[index]; * if (prog == NULL) * goto out; * goto *(prog->bpf_func + prologue_size); @@ -284,9 +284,9 @@ static void emit_bpf_tail_call(u8 **pprog) EMIT3(0x83, 0xC0, 0x01); /* add eax, 1 */ EMIT2_off32(0x89, 0x85, -STACKSIZE + 36); /* mov dword ptr [rbp - 516], eax */ - /* prog = array->prog[index]; */ + /* prog = array->ptrs[index]; */ EMIT4_off32(0x48, 0x8D, 0x84, 0xD6, /* lea rax, [rsi + rdx * 8 + offsetof(...)] */ - offsetof(struct bpf_array, prog)); + offsetof(struct bpf_array, ptrs)); EMIT3(0x48, 0x8B, 0x00); /* mov rax, qword ptr [rax] */ /* if (prog == NULL) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 139d6d2e123f..d495211d63d1 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -24,6 +24,10 @@ struct bpf_map_ops { void *(*map_lookup_elem)(struct bpf_map *map, void *key); int (*map_update_elem)(struct bpf_map *map, void *key, void *value, u64 flags); int (*map_delete_elem)(struct bpf_map *map, void *key); + + /* funcs called by prog_array and perf_event_array map */ + void *(*map_fd_get_ptr) (struct bpf_map *map, int fd); + void (*map_fd_put_ptr) (void *ptr); }; struct bpf_map { @@ -142,13 +146,13 @@ struct bpf_array { bool owner_jited; union { char value[0] __aligned(8); - struct bpf_prog *prog[0] __aligned(8); + void *ptrs[0] __aligned(8); }; }; #define MAX_TAIL_CALL_CNT 32 u64 bpf_tail_call(u64 ctx, u64 r2, u64 index, u64 r4, u64 r5); -void bpf_prog_array_map_clear(struct bpf_map *map); +void bpf_fd_array_map_clear(struct bpf_map *map); bool bpf_prog_array_compatible(struct bpf_array *array, const struct bpf_prog *fp); const struct bpf_func_proto *bpf_get_trace_printk_proto(void); diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index cb31229a6fa4..45df6572ecfd 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -150,15 +150,15 @@ static int __init register_array_map(void) } late_initcall(register_array_map); -static struct bpf_map *prog_array_map_alloc(union bpf_attr *attr) +static struct bpf_map *fd_array_map_alloc(union bpf_attr *attr) { - /* only bpf_prog file descriptors can be stored in prog_array map */ + /* only file descriptors can be stored in this type of map */ if (attr->value_size != sizeof(u32)) return ERR_PTR(-EINVAL); return array_map_alloc(attr); } -static void prog_array_map_free(struct bpf_map *map) +static void fd_array_map_free(struct bpf_map *map) { struct bpf_array *array = container_of(map, struct bpf_array, map); int i; @@ -167,21 +167,21 @@ static void prog_array_map_free(struct bpf_map *map) /* make sure it's empty */ for (i = 0; i < array->map.max_entries; i++) - BUG_ON(array->prog[i] != NULL); + BUG_ON(array->ptrs[i] != NULL); kvfree(array); } -static void *prog_array_map_lookup_elem(struct bpf_map *map, void *key) +static void *fd_array_map_lookup_elem(struct bpf_map *map, void *key) { return NULL; } /* only called from syscall */ -static int prog_array_map_update_elem(struct bpf_map *map, void *key, - void *value, u64 map_flags) +static int fd_array_map_update_elem(struct bpf_map *map, void *key, + void *value, u64 map_flags) { struct bpf_array *array = container_of(map, struct bpf_array, map); - struct bpf_prog *prog, *old_prog; + void *new_ptr, *old_ptr; u32 index = *(u32 *)key, ufd; if (map_flags != BPF_ANY) @@ -191,57 +191,75 @@ static int prog_array_map_update_elem(struct bpf_map *map, void *key, return -E2BIG; ufd = *(u32 *)value; - prog = bpf_prog_get(ufd); - if (IS_ERR(prog)) - return PTR_ERR(prog); - - if (!bpf_prog_array_compatible(array, prog)) { - bpf_prog_put(prog); - return -EINVAL; - } + new_ptr = map->ops->map_fd_get_ptr(map, ufd); + if (IS_ERR(new_ptr)) + return PTR_ERR(new_ptr); - old_prog = xchg(array->prog + index, prog); - if (old_prog) - bpf_prog_put_rcu(old_prog); + old_ptr = xchg(array->ptrs + index, new_ptr); + if (old_ptr) + map->ops->map_fd_put_ptr(old_ptr); return 0; } -static int prog_array_map_delete_elem(struct bpf_map *map, void *key) +static int fd_array_map_delete_elem(struct bpf_map *map, void *key) { struct bpf_array *array = container_of(map, struct bpf_array, map); - struct bpf_prog *old_prog; + void *old_ptr; u32 index = *(u32 *)key; if (index >= array->map.max_entries) return -E2BIG; - old_prog = xchg(array->prog + index, NULL); - if (old_prog) { - bpf_prog_put_rcu(old_prog); + old_ptr = xchg(array->ptrs + index, NULL); + if (old_ptr) { + map->ops->map_fd_put_ptr(old_ptr); return 0; } else { return -ENOENT; } } +static void *prog_fd_array_get_ptr(struct bpf_map *map, int fd) +{ + struct bpf_array *array = container_of(map, struct bpf_array, map); + struct bpf_prog *prog = bpf_prog_get(fd); + if (IS_ERR(prog)) + return prog; + + if (!bpf_prog_array_compatible(array, prog)) { + bpf_prog_put(prog); + return ERR_PTR(-EINVAL); + } + return prog; +} + +static void prog_fd_array_put_ptr(void *ptr) +{ + struct bpf_prog *prog = ptr; + + bpf_prog_put_rcu(prog); +} + /* decrement refcnt of all bpf_progs that are stored in this map */ -void bpf_prog_array_map_clear(struct bpf_map *map) +void bpf_fd_array_map_clear(struct bpf_map *map) { struct bpf_array *array = container_of(map, struct bpf_array, map); int i; for (i = 0; i < array->map.max_entries; i++) - prog_array_map_delete_elem(map, &i); + fd_array_map_delete_elem(map, &i); } static const struct bpf_map_ops prog_array_ops = { - .map_alloc = prog_array_map_alloc, - .map_free = prog_array_map_free, + .map_alloc = fd_array_map_alloc, + .map_free = fd_array_map_free, .map_get_next_key = array_map_get_next_key, - .map_lookup_elem = prog_array_map_lookup_elem, - .map_update_elem = prog_array_map_update_elem, - .map_delete_elem = prog_array_map_delete_elem, + .map_lookup_elem = fd_array_map_lookup_elem, + .map_update_elem = fd_array_map_update_elem, + .map_delete_elem = fd_array_map_delete_elem, + .map_fd_get_ptr = prog_fd_array_get_ptr, + .map_fd_put_ptr = prog_fd_array_put_ptr, }; static struct bpf_map_type_list prog_array_type __read_mostly = { diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index fafa74161445..67c380cfa9ca 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -450,7 +450,7 @@ select_insn: tail_call_cnt++; - prog = READ_ONCE(array->prog[index]); + prog = READ_ONCE(array->ptrs[index]); if (unlikely(!prog)) goto out; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index a1b14d197a4f..dc9b464fefa9 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -72,7 +72,7 @@ static int bpf_map_release(struct inode *inode, struct file *filp) /* prog_array stores refcnt-ed bpf_prog pointers * release them all when user space closes prog_array_fd */ - bpf_prog_array_map_clear(map); + bpf_fd_array_map_clear(map); bpf_map_put(map); return 0; |