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Date:   Thu, 11 Aug 2022 22:44:54 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     "zhangwensheng (E)" <zhangwensheng@huaweicloud.com>
Cc:     lee.jones@linaro.org, linux-kernel@vger.kernel.org,
        linux-block@vger.kernel.org
Subject: Re: Question: consult patch
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On Fri, Aug 12, 2022 at 11:34:59AM +0800, zhangwensheng (E) wrote:
> Hi Lee ：
>     I saw your patch because of CVE-2022-20158, the patch like below:
> 
> ---
>     mm: backing-dev: Take a reference to the bdi in use to prevent UAF

I can't see that patch anywhere, and I've not seen an bug report for it.

>     Because of a distinct lack of locking and/or reference taking,
>     blk_cleanup_queue() puts the final taken reference to the bdi, which

.. and blk_cleanup_queue also is gone upstream.

What am I missing?