When racing on adding into user cache, the new allocated from mm slab
is freed without putting user namespace.
Since the user namespace is already operated by getting, putting has
to be issued.
Signed-off-by: Hillf Danton <dhillf@gmail.com>
---
--- a/kernel/user.c 2010-11-01 19:54:12.000000000 +0800
+++ b/kernel/user.c 2010-12-23 20:42:00.000000000 +0800
@@ -158,6 +158,7 @@ struct user_struct *alloc_uid(struct use
spin_lock_irq(&uidhash_lock);
up = uid_hash_find(uid, hashent);
if (up) {
+ put_user_ns(ns);
key_put(new->uid_keyring);
key_put(new->session_keyring);
kmem_cache_free(uid_cachep, new);
--