1 files changed, 1 insertions, 1 deletions

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index a220fdb66568..59aa339a245c 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -5451,7 +5451,7 @@ struct cgroup_subsys_state *css_tryget_online_from_dir(struct dentry *dentry,
 struct cgroup_subsys_state *css_from_id(int id, struct cgroup_subsys *ss)
 {
         WARN_ON_ONCE(!rcu_read_lock_held());
-        return idr_find(&ss->css_idr, id);
+        return id > 0 ? idr_find(&ss->css_idr, id) : NULL;
 }
 
 #ifdef CONFIG_CGROUP_DEBUG