[PATCH 1/2] userns: remove dead key_put() on the create_user_ns() error path

[Tao Cui]

From: Tao Cui <cuitao@xxxxxxxxxx>

create_user_ns() jumps to fail_keyring when setup_userns_sysctls()
fails.  At that point ns was freshly allocated with
kmem_cache_zalloc() and ns->persistent_keyring_register is only ever
assigned later, lazily, from key_get_persistent()
(security/keys/persistent.c).  The key_put() therefore always
receives NULL.

Remove the dead call.

Signed-off-by: Tao Cui <cuitao@xxxxxxxxxx>
---
 kernel/user_namespace.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
index 0bed462e9b2a..e9e04ce167df 100644
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -162,9 +162,6 @@ int create_user_ns(struct cred *new)
 	ns_tree_add(ns);
 	return 0;
 fail_keyring:
-#ifdef CONFIG_PERSISTENT_KEYRINGS
-	key_put(ns->persistent_keyring_register);
-#endif
 	ns_common_free(ns);
 fail_free:
 	kmem_cache_free(user_ns_cachep, ns);
-- 
2.43.0