ipc: fix memory leak in init_mqueue_fs()

When setup_mq_sysctls() failed in init_mqueue_fs(), mqueue_inode_cachep is
not released.  In order to fix this issue, the release path is reordered.

Link: https://lkml.kernel.org/r/[email protected]
Fixes: dc55e35 ("ipc: Store mqueue sysctls in the ipc namespace")
Signed-off-by: Zhengchao Shao <[email protected]>
Cc: Alexey Gladkov <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Cc: Jingyu Wang <[email protected]>
Cc: Muchun Song <[email protected]>
Cc: Roman Gushchin <[email protected]>
Cc: Waiman Long <[email protected]>
Cc: Wei Yongjun <[email protected]>
Cc: YueHaibing <[email protected]>
Cc: Yu Zhe <[email protected]>
Cc: Manfred Spraul <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

ipc/mqueue.c

@@ -1726,7 +1726,8 @@ static int __init init_mqueue_fs(void)
 
 	if (!setup_mq_sysctls(&init_ipc_ns)) {
 		pr_warn("sysctl registration failed\n");
-		return -ENOMEM;
+		error = -ENOMEM;
+		goto out_kmem;
 	}
 
 	error = register_filesystem(&mqueue_fs_type);
@@ -1744,8 +1745,9 @@ static int __init init_mqueue_fs(void)
 out_filesystem:
 	unregister_filesystem(&mqueue_fs_type);
 out_sysctl:
-	kmem_cache_destroy(mqueue_inode_cachep);
 	retire_mq_sysctls(&init_ipc_ns);
+out_kmem:
+	kmem_cache_destroy(mqueue_inode_cachep);
 	return error;
 }