Re: selftests: seccomp_bpf failure on 5.15

Eric W. Biederman
2021-11-03T18:36:32Z

Kees Cook <keescook@chromium.org> writes:

> On Tue, Nov 02, 2021 at 01:22:19PM -0500, Eric W. Biederman wrote:
>> Kees Cook <keescook@chromium.org> writes:
>>
>> > On Thu, Oct 28, 2021 at 05:06:53PM -0500, Eric W. Biederman wrote:
>> >> Kees Cook <keescook@chromium.org> writes:
>> >>
>> >> > On Thu, Oct 28, 2021 at 12:26:26PM -0500, Eric W. Biederman wrote:
>> >>
>> >> Is it a problem that the debugger can see the signal if the process does
>> >> not?
>> >
>> > Right, I'm trying to understand that too. However, my neighbor just lost
>> > power. :|
>> >
>> > What I was in the middle of checking was what ptrace "sees" going
>> > through a fatal SIGSYS; my initial debugging attempts were weird.
>>
>> Kees have you regained power and had a chance to see my SA_IMMUTABLE
>> patch?
>
> Apologies; I got busy with other stuff, but I've tested this now. It's
> happy and I see the expected behaviors again. Note that I used the patch
> with this change:
>
> -#define SA_IMMUTABLE 0x008000000
> +#define SA_IMMUTABLE 0x00800000
>
> Tested-by: Kees Cook <keescook@chromium.org>

Thanks.

And I see you have written a test as well that should keep
this kind of bug from happening again.

Eric