Re: [PATCH v6 2/4] x86/traps: Print address on #GP

From: Jann Horn
Date: Wed Dec 18 2019 - 16:56:49 EST


On Wed, Dec 11, 2019 at 6:06 PM Borislav Petkov <bp@xxxxxxxxx> wrote:
> On Mon, Dec 09, 2019 at 03:31:18PM +0100, Jann Horn wrote:
> > I have already sent a patch to syzkaller that relaxes their parsing of GPF
> > messages (https://github.com/google/syzkaller/commit/432c7650) such that
> > changes like the one in this patch don't break it.
> > That patch has already made its way into syzbot's syzkaller instances
> > according to <https://syzkaller.appspot.com/upstream>.
>
> Ok, cool.
>
> I still think we should do the oops number marking, though, as it has
> more benefits than just syzkaller scanning for it. The first oops has always
> been of crucial importance so having the number in there:
>
> [ 2.542218] [1] general protection fault while derefing a non-canonical address 0xdfff000000000001: 0000 [#1] PREEMPT SMP
> ^
>
> would make eyeballing oopses even easier. Basically the same reason why
> you're doing this enhancement. :)
>
> So let me know if you don't have time to do it or you don't care about
> it etc, and I'll have a look.

I don't think I have time to do this in the near future. Feel free to
implement this.