bpf: grab rcu read lock for bpf_percpu_hash_update

bpf_percpu_hash_update() expects rcu lock to be held and warns if it's not, which pointed out a missing rcu read lock. Fixes: 15a07b3 ("bpf: add lookup/update support for per-cpu hash and array maps") Signed-off-by: Sasha Levin <[email protected]> Acked-by: Alexei Starovoitov <[email protected]> Acked-by: Daniel Borkmann <[email protected]> Signed-off-by: David S. Miller <[email protected]>
ambv · Feb 19, 2016 · 6bbd9a0 · 6bbd9a0
1 parent dfa2eb8
commit 6bbd9a0
Showing 1 changed file with 7 additions and 1 deletion.
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
@@ -619,7 +619,13 @@ int bpf_percpu_hash_copy(struct bpf_map *map, void *key, void *value)
 int bpf_percpu_hash_update(struct bpf_map *map, void *key, void *value,
 			   u64 map_flags)
 {
-	return __htab_percpu_map_update_elem(map, key, value, map_flags, true);
+	int ret;
+
+	rcu_read_lock();
+	ret = __htab_percpu_map_update_elem(map, key, value, map_flags, true);
+	rcu_read_unlock();
+
+	return ret;
 }
 
 static const struct bpf_map_ops htab_percpu_ops = {