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Subject: Re: [PATCH] uts: Don't randomize "struct uts_namespace".
To:     Kees Cook <keescook@chromium.org>,
        Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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 <CAGXu5jKrM_3ymnmcJ+AE1A3uVPDJykRj0z5B8sDoxM6zUnX-Rg@mail.gmail.com>
From:   Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Message-ID: <945be212-8e82-9dd8-930f-4e5c11dcae77@i-love.sakura.ne.jp>
Date:   Sat, 7 Jul 2018 08:35:28 +0900
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I'm waiting for response from makedumpfile developers.

But makedumpfile is a tool for saving kernel crash dump.
If makedumpfile cannot work, we cannot use kernel crash dump.

On 2018/07/07 8:19, Kees Cook wrote:
> On Fri, Jul 6, 2018 at 9:11 AM, Linus Torvalds
> <torvalds@linux-foundation.org> wrote:
>> On Fri, Jul 6, 2018 at 3:07 AM Tetsuo Handa
>> <penguin-kernel@i-love.sakura.ne.jp> wrote:
>>>
>>> I noticed that makedumpfile utility is failing to check kernel version, for
>>> it depends on offset of "struct uts_namespace"->name being sizeof(int).
>>
>> For something like this, we fix makedumpfile instead. This is not a
>> "user program" using system calls etc, this is something that delves
>> into the kernel dump and tries to make sense of it.
>>
>> Where is the makedumpfile source code? What is it trying to do, and why?
>>
>> One option is to just say "hey, you can't make much sense of a
>> randomized kernel dump anyway, so don't even try".
> 
> I would second this -- trying to deal with a randomized layout kernel
> dump is going to be much worse than just looking at uts_namespace. :)
> 
> -Kees
>