From: Tejun Heo <tj@kernel.org>
Date: Sun, 23 Jul 2017 08:14:15 -0400
Subject: [PATCH] cgroup: fix error return value from cgroup_subtree_control()
References: bnc#1060662
Patch-mainline: v4.12.6
Git-commit: 3c74541777302eec43a0d1327c4d58b8659a776b

commit 3c74541777302eec43a0d1327c4d58b8659a776b upstream.

While refactoring, f7b2814bb9b6 ("cgroup: factor out
cgroup_{apply|finalize}_control() from
cgroup_subtree_control_write()") broke error return value from the
function.  The return value from the last operation is always
overridden to zero.  Fix it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 kernel/cgroup/cgroup.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 916833f51bad..2c62e4b3f198 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -2921,11 +2921,11 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of,
 	cgrp->subtree_control &= ~disable;
 
 	ret = cgroup_apply_control(cgrp);
-
 	cgroup_finalize_control(cgrp, ret);
+	if (ret)
+		goto out_unlock;
 
 	kernfs_activate(cgrp->kn);
-	ret = 0;
 out_unlock:
 	cgroup_kn_unlock(of->kn);
 	return ret ?: nbytes;
-- 
2.14.2