[PATCH] cgroups: fix possible use after free

[Paul Menage]

On Tue, Feb 10, 2009 at 1:31 AM, Li Zefan <lizf at cn.fujitsu.com> wrote:
> 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 at ZenIV.linux.org.uk>
> Signed-off-by: Li Zefan <lizf at cn.fujitsu.com>

Acked-by: Paul Menage <menage at google.com>

Seems like the safest fix.

Paul