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Date: Tue, 10 Feb 2009 16:01:01 -0800
Message-ID: <6599ad830902101601g6098acf7ua25138a5c6c7db92@mail.gmail.com>
Subject: Re: [PATCH] cgroups: fix possible use after free
From: Paul Menage <menage@google.com>
To: Li Zefan <lizf@cn.fujitsu.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
       Al Viro <viro@zeniv.linux.org.uk>, LKML <linux-kernel@vger.kernel.org>,
       Linux Containers <containers@lists.linux-foundation.org>
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On Tue, Feb 10, 2009 at 1:31 AM, Li Zefan <lizf@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@ZenIV.linux.org.uk>
> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>

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

Seems like the safest fix.

Paul