Commit eb4aec84 authored Sep 18, 2014 by Zefan Li Committed by Tejun Heo Sep 18, 2014

cgroup: fix unbalanced locking



cgroup_pidlist_start() holds cgrp->pidlist_mutex and then calls
pidlist_array_load(), and cgroup_pidlist_stop() releases the mutex.

It is wrong that we release the mutex in the failure path in
pidlist_array_load(), because cgroup_pidlist_stop() will be called
no matter if cgroup_pidlist_start() returns errno or not.

Fixes: 4bac00d1
Cc: <stable@vger.kernel.org> # 3.14+
Signed-off-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>

parent aa32362f

kernel/cgroup.c

+0 −1

Original line number	Diff line number	Diff line
		@@ -3985,7 +3985,6 @@ static int pidlist_array_load(struct cgroup *cgrp, enum cgroup_filetype type,

		l = cgroup_pidlist_find_create(cgrp, type);
		if (!l) {
		mutex_unlock(&cgrp->pidlist_mutex);
		pidlist_free(array);
		return -ENOMEM;
		}