cpuset: fix a race condition in __cpuset_node_allowed_softwall()
It's not safe to access task's cpuset after releasing task_lock().
Holding callback_mutex won't help.
Cc: <stable@vger.kernel.org>
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index dba9e4a..e6b1b66 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -2482,9 +2482,9 @@
task_lock(current);
cs = nearest_hardwall_ancestor(task_cs(current));
+ allowed = node_isset(node, cs->mems_allowed);
task_unlock(current);
- allowed = node_isset(node, cs->mems_allowed);
mutex_unlock(&callback_mutex);
return allowed;
}