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Message-ID: <ec762677-f8d4-94ab-e7b3-adee45a052a1@kernel.dk>
Date:   Thu, 15 Jun 2023 07:13:31 -0600
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Subject: Re: [PATCH] tools/io_uring: Fix missing check for return value of
 malloc()
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To:     Ammar Faizi <ammarfaizi2@gnuweeb.org>,
        Chenyuan Mi <cymi20@fudan.edu.cn>
Cc:     Pavel Begunkov <asml.silence@gmail.com>,
        io-uring Mailing List <io-uring@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
References: <20230615125045.125172-1-cymi20@fudan.edu.cn>
 <34898926-681e-1790-4303-e2b54e793a62@gnuweeb.org>
From:   Jens Axboe <axboe@kernel.dk>
In-Reply-To: <34898926-681e-1790-4303-e2b54e793a62@gnuweeb.org>
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On 6/15/23 7:00?AM, Ammar Faizi wrote:
> On 6/15/23 7:50 PM, Chenyuan Mi wrote:
>> The malloc() function may return NULL when it fails,
>> which may cause null pointer deference in kmalloc(),
> 
> It's a userspace app, there is no kmalloc(). Also, I don't think it's
> worth to fix a missing ENOMEM handling for that old test program. But
> anyway, let's wait for maintainers' comment on this.

Definitely not worth it, and I find it odd how the author would target
just one of multiple allocations in that file. I'm guessing it's because
this checker only checks for malloc(), and no thought has otherwise gone
into a) if the patch makes any sense at all, and b) if it does make
sense, are there potentially other cases to consider?

-- 
Jens Axboe