kernel/user.c: clean up some leftover code

The out_unlock label is misleading; no unlocking happens after it, so
just return NULL directly.

Also, nothing between the kmem_cache_zalloc() that creates new and the
two key_put() can initialize new->uid_keyring or new->session_keyring,
so those calls are no-ops.

Link: http://lkml.kernel.org/r/20190424200404.9114-1-linux@rasmusvillemoes.dk
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/user.c

@@ -185,7 +185,7 @@ struct user_struct *alloc_uid(kuid_t uid)
 	if (!up) {
 		new = kmem_cache_zalloc(uid_cachep, GFP_KERNEL);
 		if (!new)
-			goto out_unlock;
+			return NULL;
 
 		new->uid = uid;
 		refcount_set(&new->__count, 1);
@@ -199,8 +199,6 @@ struct user_struct *alloc_uid(kuid_t uid)
 		spin_lock_irq(&uidhash_lock);
 		up = uid_hash_find(uid, hashent);
 		if (up) {
-			key_put(new->uid_keyring);
-			key_put(new->session_keyring);
 			kmem_cache_free(uid_cachep, new);
 		} else {
 			uid_hash_insert(new, hashent);
@@ -210,9 +208,6 @@ struct user_struct *alloc_uid(kuid_t uid)
 	}
 
 	return up;
-
-out_unlock:
-	return NULL;
 }
 
 static int __init uid_cache_init(void)