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Date:   Fri, 17 May 2019 10:23:12 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     stummala@codeaurora.org
Cc:     Junxiao Bi <junxiao.bi@oracle.com>,
        Joel Becker <jlbec@evilplan.org>,
        Christoph Hellwig <hch@lst.de>,
        Al Viro <viro@zeniv.linux.org.uk>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] configfs: Fix use-after-free when accessing
 sd->s_dentry
Message-ID: <20190517082312.GA13457@lst.de>
References: <1546514295-24818-1-git-send-email-stummala@codeaurora.org> <20190131032011.GC7308@codeaurora.org> <0081e5c8083f5ed9f1c1e9b456739728@codeaurora.org>
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On Thu, May 16, 2019 at 06:27:53PM +0530, stummala@codeaurora.org wrote:
> Hi Christoph, Al,
>
> Can you please consider this patch for merging?

I've been sitting on this for a while, mostly because I can't convince
myself it is safe.  What protects other threads from using ->s_dentry
just when we clear it?  Also why would sd->s_dentry == dentry ever be
false?