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From:   Yun Levi <ppbuk5246@gmail.com>
Date:   Thu, 24 Feb 2022 11:28:24 +0900
Message-ID: <CAM7-yPSmmfgAAGiK+oQq8JD0Xu9S-Ys-WaBPgM8XU5Jgdm-NjA@mail.gmail.com>
Subject: Re: [PATCH] fs/exec.c: Avoid a race in formats
To:     "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     Al Viro <viro@zeniv.linux.org.uk>,
        Kees Cook <keescook@chromium.org>,
        linux-fsdevel@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Thu, Feb 24, 2022 at 11:25 AM Eric W. Biederman
<ebiederm@xmission.com> wrote:
> I took a quick look and unregistering in the module exit routine looks
> safe, as set_binfmt takes a module reference, and so prevents the module
> from being unloaded.
>
> If you can find a bug with existing in-kernel code that would be
> interesting.  Otherwise you are making up assumptions that don't current
> match the code and saying the code is bugging with respect to
> assumptions that do not hold.
>
> The code in the kernel is practical not an implementation of some
> abstract that is robust for every possible use case.
>
> Eric

Thanks and sorry for making a noise.