From: Hou Tao houtao1@huawei.com
[ Upstream commit 87e9675a0dfd0bf4a36550e4a0e673038ec67aee ]
When security_bpf_map_create() in map_create() fails, map_create() will call btf_put() and ->map_free() callback to free the map. It doesn't free the btf_record of map value, so add the missed btf_record_free() when map creation fails.
However btf_record_free() needs to be called after ->map_free() just like bpf_map_free_deferred() did, because ->map_free() may use the btf_record to free the special fields in preallocated map value. So factor out bpf_map_free() helper to free the map, btf_record, and btf orderly and use the helper in both map_create() and bpf_map_free_deferred().
Signed-off-by: Hou Tao houtao1@huawei.com Acked-by: Jiri Olsa jolsa@kernel.org Link: https://lore.kernel.org/r/20240912012845.3458483-2-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov ast@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/bpf/syscall.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-)
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index f45ed6adc092a..92590ddb2042d 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -733,15 +733,11 @@ void bpf_obj_free_fields(const struct btf_record *rec, void *obj) } }
-/* called from workqueue */ -static void bpf_map_free_deferred(struct work_struct *work) +static void bpf_map_free(struct bpf_map *map) { - struct bpf_map *map = container_of(work, struct bpf_map, work); struct btf_record *rec = map->record; struct btf *btf = map->btf;
- security_bpf_map_free(map); - bpf_map_release_memcg(map); /* implementation dependent freeing */ map->ops->map_free(map); /* Delay freeing of btf_record for maps, as map_free @@ -760,6 +756,16 @@ static void bpf_map_free_deferred(struct work_struct *work) btf_put(btf); }
+/* called from workqueue */ +static void bpf_map_free_deferred(struct work_struct *work) +{ + struct bpf_map *map = container_of(work, struct bpf_map, work); + + security_bpf_map_free(map); + bpf_map_release_memcg(map); + bpf_map_free(map); +} + static void bpf_map_put_uref(struct bpf_map *map) { if (atomic64_dec_and_test(&map->usercnt)) { @@ -1411,8 +1417,7 @@ static int map_create(union bpf_attr *attr) free_map_sec: security_bpf_map_free(map); free_map: - btf_put(map->btf); - map->ops->map_free(map); + bpf_map_free(map); put_token: bpf_token_put(token); return err;