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Date: Tue, 14 May 2013 08:38:10 -0700
From: Tejun Heo <tj@kernel.org>
To: Li Zefan <lizefan@huawei.com>
Cc: LSM <linux-security-module@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>, Cgroups <cgroups@vger.kernel.org>,
        Containers <containers@lists.linux-foundation.org>,
        Casey Schaufler <casey@schaufler-ca.com>,
        Ivan Bulatovic <combuster@archlinux.us>
Subject: Re: [PATCH] cgroup: initialize xattr before calling d_instantiate()
Message-ID: <20130514153810.GD6795@mtj.dyndns.org>
References: <51922394.2020002@huawei.com>
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On Tue, May 14, 2013 at 07:44:20PM +0800, Li Zefan wrote:
> cgroup_create_file() calls d_instantiate(), which may decide to look
> at the xattrs on the file. Smack always does this and SELinux can be
> configured to do so.
> 
> But cgroup_add_file() didn't initialize xattrs before calling
> cgroup_create_file(), which finally leads to dereferencing NULL
> dentry->d_fsdata.
> 
> This bug has been there since cgroup xattr was introduced.
> 
> Cc: <stable@vger.kernel.org> # 3.8.x
> Reported-by: Ivan Bulatovic <combuster@archlinux.us>
> Reported-by: Casey Schaufler <casey@schaufler-ca.com>
> Signed-off-by: Li Zefan <lizefan@huawei.com>

Applied to cgroup/for-3.10-fixes.

Thanks.

-- 
tejun