diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 730e692e002f..b8e020499285 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -258,6 +258,18 @@ struct bpf_list_node_kern { void *owner; } __attribute__((aligned(8))); +/* 'Ownership' of program-containing map is claimed by the first program + * that is going to use this map or by the first program which FD is + * stored in the map to make sure that all callers and callees have the + * same prog type, JITed flag and xdp_has_frags flag. + */ +struct bpf_map_owner { + enum bpf_prog_type type; + bool jited; + bool xdp_has_frags; + const struct btf_type *attach_func_proto; +}; + struct bpf_map { /* The first two cachelines with read-mostly members of which some * are also accessed in fast-path (e.g. ops, max_entries). @@ -296,18 +308,8 @@ struct bpf_map { }; struct mutex freeze_mutex; atomic64_t writecnt; - /* 'Ownership' of program-containing map is claimed by the first program - * that is going to use this map or by the first program which FD is - * stored in the map to make sure that all callers and callees have the - * same prog type, JITed flag and xdp_has_frags flag. - */ - struct { - const struct btf_type *attach_func_proto; - spinlock_t lock; - enum bpf_prog_type type; - bool jited; - bool xdp_has_frags; - } owner; + spinlock_t owner_lock; + struct bpf_map_owner *owner; bool bypass_spec_v1; bool frozen; /* write-once; write-protected by freeze_mutex */ bool free_after_mult_rcu_gp; @@ -1818,6 +1820,16 @@ static inline bool bpf_map_flags_access_ok(u32 access_flags) (BPF_F_RDONLY_PROG | BPF_F_WRONLY_PROG); } +static inline struct bpf_map_owner *bpf_map_owner_alloc(struct bpf_map *map) +{ + return kzalloc(sizeof(*map->owner), GFP_ATOMIC); +} + +static inline void bpf_map_owner_free(struct bpf_map *map) +{ + kfree(map->owner); +} + struct bpf_event_entry { struct perf_event *event; struct file *perf_file; diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 5eaaf95048ab..c3369c66eae8 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -2262,28 +2262,29 @@ static 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; struct bpf_prog_aux *aux = fp->aux; + bool ret = false; if (fp->kprobe_override) - return false; + return ret; - spin_lock(&map->owner.lock); - if (!map->owner.type) { - /* There's no owner yet where we could check for - * compatibility. - */ - map->owner.type = prog_type; - map->owner.jited = fp->jited; - map->owner.xdp_has_frags = aux->xdp_has_frags; - map->owner.attach_func_proto = aux->attach_func_proto; + spin_lock(&map->owner_lock); + /* There's no owner yet where we could check for compatibility. */ + if (!map->owner) { + map->owner = bpf_map_owner_alloc(map); + if (!map->owner) + goto err; + map->owner->type = prog_type; + map->owner->jited = fp->jited; + map->owner->xdp_has_frags = aux->xdp_has_frags; + map->owner->attach_func_proto = aux->attach_func_proto; ret = true; } else { - ret = map->owner.type == prog_type && - map->owner.jited == fp->jited && - map->owner.xdp_has_frags == aux->xdp_has_frags; + ret = map->owner->type == prog_type && + map->owner->jited == fp->jited && + map->owner->xdp_has_frags == aux->xdp_has_frags; if (ret && - map->owner.attach_func_proto != aux->attach_func_proto) { + map->owner->attach_func_proto != aux->attach_func_proto) { switch (prog_type) { case BPF_PROG_TYPE_TRACING: case BPF_PROG_TYPE_LSM: @@ -2296,8 +2297,8 @@ static bool __bpf_prog_map_compatible(struct bpf_map *map, } } } - spin_unlock(&map->owner.lock); - +err: + spin_unlock(&map->owner_lock); return ret; } diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 1d6bd012de9e..98f3f206d112 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -698,6 +698,7 @@ static void bpf_map_free_deferred(struct work_struct *work) security_bpf_map_free(map); bpf_map_release_memcg(map); + bpf_map_owner_free(map); /* implementation dependent freeing */ map->ops->map_free(map); /* Delay freeing of btf_record for maps, as map_free @@ -715,7 +716,6 @@ static void bpf_map_free_deferred(struct work_struct *work) */ btf_put(btf); } - static void bpf_map_put_uref(struct bpf_map *map) { if (atomic64_dec_and_test(&map->usercnt)) { @@ -807,12 +807,12 @@ static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) struct bpf_map *map = filp->private_data; u32 type = 0, jited = 0; - if (map_type_contains_progs(map)) { - spin_lock(&map->owner.lock); - type = map->owner.type; - jited = map->owner.jited; - spin_unlock(&map->owner.lock); + spin_lock(&map->owner_lock); + if (map->owner) { + type = map->owner->type; + jited = map->owner->jited; } + spin_unlock(&map->owner_lock); seq_printf(m, "map_type:\t%u\n" @@ -1262,7 +1262,7 @@ static int map_create(union bpf_attr *attr) atomic64_set(&map->refcnt, 1); atomic64_set(&map->usercnt, 1); mutex_init(&map->freeze_mutex); - spin_lock_init(&map->owner.lock); + spin_lock_init(&map->owner_lock); if (attr->btf_key_type_id || attr->btf_value_type_id || /* Even the map's value is a kernel's struct,