Re: [PATCH 13/20] signal: Implement force_fatal_sig

From: Eric W. Biederman
Date: Thu Oct 21 2021 - 12:33:54 EST


Kees Cook <keescook@xxxxxxxxxxxx> writes:

> On Wed, Oct 20, 2021 at 12:43:59PM -0500, Eric W. Biederman wrote:
>> This is interesting both because it makes force_sigsegv simpler and
>> because there are a couple of buggy places in the kernel that call
>> do_exit(SIGILL) or do_exit(SIGSYS) because there is no straight
>> forward way today for those places to simply force the exit of a
>> process with the chosen signal. Creating force_fatal_sig allows
>> those places to be implemented with normal signal exits.
>
> I assume this is talking about seccomp()? :) Should a patch be included
> in this series to change those?

Actually it is not talking about seccomp. As far as I can tell seccomp
is deliberately only killing a single thread when it calls do_exit.

I am thinking about places where we really want the entire process to
die and not just a single thread. Please see the following changes
where I actually use force_fatal_sig.

Eric