From: Tejun Heo tj@kernel.org
commit c596687a008b579c503afb7a64fcacc7270fae9e upstream.
While adding handling for dying task group leaders c03cd7738a83 ("cgroup: Include dying leaders with live threads in PROCS iterations") added an inverted cset skip condition to css_task_iter_advance_css_set(). It should skip cset if it's completely empty but was incorrectly testing for the inverse condition for the dying_tasks list. Fix it.
Signed-off-by: Tejun Heo tj@kernel.org Fixes: c03cd7738a83 ("cgroup: Include dying leaders with live threads in PROCS iterations") Reported-by: syzbot+d4bba5ccd4f9a2a68681@syzkaller.appspotmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- kernel/cgroup/cgroup.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -4154,7 +4154,7 @@ static void css_task_iter_advance_css_se it->task_pos = NULL; return; } - } while (!css_set_populated(cset) && !list_empty(&cset->dying_tasks)); + } while (!css_set_populated(cset) && list_empty(&cset->dying_tasks));
if (!list_empty(&cset->tasks)) it->task_pos = cset->tasks.next;