Re: [regression v4.17-rc0] Re: FORTIFY_SOURCE breaks ARM compilation in -next -- was Re: ARM compile failure in Re: linux-next: Tree for Apr 4

[Kees Cook <keescook@chromium.org>]

On Fri, Apr 20, 2018 at 12:34 AM, Pavel Machek <pavel@ucw.cz> wrote:
> On Sun 2018-04-15 11:00:06, Kees Cook wrote:
>> On Sun, Apr 15, 2018 at 10:39 AM, Pavel Machek <pavel@ucw.cz> wrote:
>> > Hi!
>> >
>> >> Thanks.
>> >>
>> >> Ok, let me try to bisect it. Compile-problem should be easy...
>> >>
>> >> Hmm. And as it is compile-problem in single file, it should even be
>> >> reasonably fast. I did not realize how easy it would be:
>> >>
>> >> #!/bin/bash
>> >> set -e
>> >> cp config.ok .config
>> >> yes '' | ARCH=arm make lib/string.o
>> >>
>> >> And the winner is:
>> >>
>> >> ee333554fed55555a986a90bb097ac7f9d6f05bf is the first bad commit
>> >> commit ee333554fed55555a986a90bb097ac7f9d6f05bf
>> >> Author: Jinbum Park <jinb.park7@gmail.com>
>> >> Date:   Tue Mar 6 01:39:24 2018 +0100
>> > ...
>> >
>> >>     Acked-by: Kees Cook <keescook@chromium.org>
>> >>     Signed-off-by: Jinbum Park <jinb.park7@gmail.com>
>> >>     Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
>> >
>> > So I bisect a problem in -next, and patch is merged to Linus,
>> > _anyway_, breaking compilation there? Neither Jinbum nor Russell even
>> > bother to comment.
>>
>> Hi! Sorry I lost this email in my inbox. It seems this is specific to
>> a particular subset of arm architectures? (My local builds of arm all
>> succeed, for example. Can you send your failing config?) I'll take a
>> closer look on Monday if Daniel doesn't beat me to it.
>
> Daniel, Kees: any news?
>
> I'm aware you did not specify which Monday :-).

Hi! Sorry, I got distracted. So the .config you sent me builds fine
with my cross compiler. I suspect this is something specific to ELDK's
compiler. I can try some other compiler versions. What version of gcc
is failing?

-Kees

-- 
Kees Cook
Pixel Security