cgroups: fix possible use after free

In cgroup_kill_sb(), root is freed before sb is detached from the list, so
another sget() may find this sb and call cgroup_test_super(), which will
access the root that has been freed.

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Li Zefan 2009-02-18 14:48:20 -08:00 committed by Linus Torvalds
parent 1cf6e7d83b
commit 67e055d144

View File

@ -1122,8 +1122,8 @@ static void cgroup_kill_sb(struct super_block *sb) {
mutex_unlock(&cgroup_mutex);
kfree(root);
kill_litter_super(sb);
kfree(root);
}
static struct file_system_type cgroup_fs_type = {