diff options
| author | Johannes Weiner <[email protected]> | 2016-07-26 15:26:58 -0700 |
|---|---|---|
| committer | Linus Torvalds <[email protected]> | 2016-07-26 16:19:19 -0700 |
| commit | 1fe4d021acbc356723818a633fe0a10c59c2a4c1 (patch) | |
| tree | ee83530151ecf806ff619a1043fb4c035fc6d7cb | |
| parent | 25843c2b21d675c68e512daa4a2b50a18f7a840d (diff) | |
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/[email protected]
Signed-off-by: Johannes Weiner <[email protected]>
Cc: Vladimir Davydov <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Nikolay Borisov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
| -rw-r--r-- | kernel/cgroup.c | 8 |
1 files changed, 1 insertions, 7 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 75c0ff00aca6..3108150e47b1 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -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; - } + idr_remove(&cgroup_hierarchy_idr, root->hierarchy_id); } 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); } |