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Date:   Thu, 2 Jan 2020 14:03:03 -0800
From:   Kees Cook <keescook@chromium.org>
To:     Alexander Popov <alex.popov@linux.com>
Cc:     Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-kernel@vger.kernel.org, notify@kernel.org
Subject: Re: [PATCH v1 1/1] lkdtm/stackleak: Make the stack erasing test more
 verbose
Message-ID: <202001021402.EDBC5114D@keescook>
References: <20191219145416.435508-1-alex.popov@linux.com>
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 <201912301443.9B8F6CA6@keescook>
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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