Merge branch 'two-tiny-fixes-for-btf-record'

Hou Tao says:

====================
The tiny patch set aims to fix two problems found during the development
of supporting dynptr key in hash table. Patch #1 fixes the missed
btf_record_free() when map creation fails and patch #2 fixes the missed
kfree() when there is no special field in the passed btf.
====================

Link: https://lore.kernel.org/r/20240912012845.3458483-1-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

kernel/bpf/btf.c

@@ -5572,8 +5572,10 @@ btf_parse_struct_metas(struct bpf_verifier_log *log, struct btf *btf)
 		aof->ids[aof->cnt++] = i;
 	}
 
-	if (!aof->cnt)
+	if (!aof->cnt) {
+		kfree(aof);
 		return NULL;
+	}
 	sort(&aof->ids, aof->cnt, sizeof(aof->ids[0]), btf_id_cmp_func, NULL);
 
 	for (i = 1; i < n; i++) {

kernel/bpf/syscall.c

@@ -735,15 +735,11 @@ 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
@@ -762,6 +758,16 @@ 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)) {
@@ -1413,8 +1419,7 @@ 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;