From 6c7ca6a02f8f9549a438a08a23c6327580ecf3d6 Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Mon, 29 Sep 2025 11:41:16 +0200 Subject: [PATCH] mount: handle NULL values in mnt_ns_release() When calling in listmount() mnt_ns_release() may be passed a NULL pointer. Handle that case gracefully. Signed-off-by: Christian Brauner Signed-off-by: Linus Torvalds --- fs/namespace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/namespace.c b/fs/namespace.c index 38609066cf33..1ee17a00c311 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -180,7 +180,7 @@ static void mnt_ns_tree_add(struct mnt_namespace *ns) static void mnt_ns_release(struct mnt_namespace *ns) { /* keep alive for {list,stat}mount() */ - if (refcount_dec_and_test(&ns->passive)) { + if (ns && refcount_dec_and_test(&ns->passive)) { fsnotify_mntns_delete(ns); put_user_ns(ns->user_ns); kfree(ns); -- 2.20.1