Re: [PATCH] uts: Don't randomize "struct uts_namespace".

From: Tetsuo Handa
Date: Fri Jul 06 2018 - 19:35:36 EST


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@xxxxxxxxxxxxxxxxxxxx> wrote:
>> On Fri, Jul 6, 2018 at 3:07 AM Tetsuo Handa
>> <penguin-kernel@xxxxxxxxxxxxxxxxxxx> 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
>