Re: [PATCH 6/8] cgroup: mount cgroupns-root when inside non-init cgroupns

From fc54592077533ff2ff90ed54b72bf03b4378ca9f Mon Sep 17 00:00:00 2001
From: Serge Hallyn <serge.hallyn-GeWIH/nMZzLQT0dZR+AlfA@public.gmane.org>
Date: Thu, 31 Dec 2015 16:55:19 -0800
Subject: [PATCH 1/1] cgroup_release_agent: grab css_set_lock around
 cgroup_path()

Reported-by: Sergey Senozhatsky <redacted>
Signed-off-by: Serge Hallyn <serge.hallyn-GeWIH/nMZzLQT0dZR+AlfA@public.gmane.org>
---
 kernel/cgroup.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 4812f59..d10f127 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c

@@ -5769,7 +5769,9 @@ static void cgroup_release_agent(struct work_struct *work)
 	if (!pathbuf || !agentbuf)
 		goto out;
 
+	spin_lock_bh(&css_set_lock);
 	path = cgroup_path(cgrp, pathbuf, PATH_MAX);
+	spin_unlock_bh(&css_set_lock);
 	if (!path)
 		goto out;
 

-- 
2.5.0