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Date:   Wed, 14 Jun 2023 10:14:59 -0600
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Subject: Re: [PATCH] io_uring/kbuf: fix missing check for return value of
 io_buffer_get_list()
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To:     Chenyuan Mi <cymi20@fudan.edu.cn>
Cc:     asml.silence@gmail.com, io-uring@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20230614151246.116391-1-cymi20@fudan.edu.cn>
From:   Jens Axboe <axboe@kernel.dk>
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On 6/14/23 9:12?AM, Chenyuan Mi wrote:
> The io_buffer_get_list() function may return NULL, which may
> cause null pointer deference, and other callsites of
> io_buffer_get_list() all do Null check. Add Null check for
> return value of io_buffer_get_list().
> 
> Found by our static analysis tool.

Ah, was going to ask about a test case, but I guess it doesn't exist.
I don't think this can happen, as the legacy buffer groups can only ever
get added, and only get removed when the ring goes away.

-- 
Jens Axboe