Patch "cgroup: fix error return value from cgroup_subtree_control()" has been added to the 4.12-stable tree

This is a note to let you know that I've just added the patch titled

cgroup: fix error return value from cgroup_subtree_control()

to the 4.12-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
cgroup-fix-error-return-value-from-cgroup_subtree_control.patch
and it can be found in the queue-4.12 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Tejun Heo <[email protected]>
Date: Sun, 23 Jul 2017 08:14:15 -0400
Subject: cgroup: fix error return value from cgroup_subtree_control()

From: Tejun Heo <[email protected]>

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.

---
 kernel/cgroup/cgroup.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

@@ -2921,11 +2921,11 @@ static ssize_t cgroup_subtree_control_wr
 	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;

Patches currently in stable-queue which might be from [email protected] are

queue-4.12/cgroup-don-t-call-migration-methods-if-there-are-no-tasks-to-migrate.patch queue-4.12/cgroup-create-dfl_root-files-on-subsys-registration.patch queue-4.12/cgroup-fix-error-return-value-from-cgroup_subtree_control.patch queue-4.12/workqueue-restore-wq_unbound-max_active-1-to-be-ordered.patch queue-4.12/libata-array-underflow-in-ata_find_dev.patch