Re: [PATCH v1 1/1] lkdtm/stackleak: Make the stack erasing test more verbose

From: Kees Cook
Date: Thu Jan 02 2020 - 17:03:08 EST


On Thu, Jan 02, 2020 at 02:26:39AM +0300, Alexander Popov wrote:
> On 31.12.2019 01:46, Kees Cook wrote:
> > On Tue, Dec 31, 2019 at 01:20:24AM +0300, Alexander Popov wrote:
> >> On 30.12.2019 21:37, Kees Cook wrote:
> >>> Hi! I try to keep the "success" conditions for LKDTM tests to be a
> >>> system exception, so doing "BUG" on a failure is actually against the
> >>> design. So, really, a test harness needs to know to check dmesg for the
> >>> results here. It almost looks like this check shouldn't live in LKDTM,
> >>> but since it feels like other LKDTM tests, I'm happy to keep it there
> >>> for now.
> >>
> >> Do you mean that you will apply this patch?
> >
> > Sorry for my confusing reply! I meant that I don't want to apply the
> > patch, but I'm find to leave the stackleak check in LKDTM.
>
> Kees, I think I see a solution.
>
> Would you agree if I use dump_stack() instead of BUG() in case of test failure?
> That would provide enough info for debugging and would NOT break your design.

I would be fine with that, yes! :)

--
Kees Cook