cgroup: fix idr leak for the first cgroup root
The valid cgroup hierarchy ID range includes 0, so we can't filter for positive numbers when freeing it, or it'll leak the first ID. No big deal, just disruptive when reading the code. The ID is freed during error handling and when the reference count hits zero, so the double-free test is not necessary; remove it. Link: http://lkml.kernel.org/r/20160617162359.GB19084@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Cc: Tejun Heo <tj@kernel.org> Cc: Nikolay Borisov <kernel@kyup.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
25843c2b21
commit
1fe4d021ac
|
@ -1160,18 +1160,12 @@ static void cgroup_exit_root_id(struct cgroup_root *root)
|
|||
{
|
||||
lockdep_assert_held(&cgroup_mutex);
|
||||
|
||||
if (root->hierarchy_id) {
|
||||
idr_remove(&cgroup_hierarchy_idr, root->hierarchy_id);
|
||||
root->hierarchy_id = 0;
|
||||
}
|
||||
}
|
||||
|
||||
static void cgroup_free_root(struct cgroup_root *root)
|
||||
{
|
||||
if (root) {
|
||||
/* hierarchy ID should already have been released */
|
||||
WARN_ON_ONCE(root->hierarchy_id);
|
||||
|
||||
idr_destroy(&root->cgroup_idr);
|
||||
kfree(root);
|
||||
}
|
||||
|
|
Loading…
Reference in a new issue