Re: general protection fault in perf_misc_flags

From: Dmitry Vyukov
Date: Mon Sep 28 2020 - 06:34:12 EST


On Mon, Sep 28, 2020 at 10:54 AM Borislav Petkov <bp@xxxxxxxxx> wrote:
>
> On Mon, Sep 28, 2020 at 10:40:19AM +0200, Dmitry Vyukov wrote:
> > I meant the kernel self-corrupts itself, that just wasn't detected by
> > KASAN, page protections, etc.
>
> Well, Nick already asked this but we're marking all kernel text RO early
> during boot. So it either is happening before that or something else
> altogether is going on.
>
> And if that is a kernel issue, I believe we should've heard by now from
> others. Or maybe this happens only in VMs.
>
> Questions over questions...

I don't have answers to all of the questions, but syzkaller produces a
pretty unique workload. It has found thousands of bugs that you have
not heard from others:
https://syzkaller.appspot.com/upstream#open
https://syzkaller.appspot.com/upstream/fixed
In particular there are hundreds of known and active potential memory
corruption bugs.

It may be related to VMs, but also may well not be related to VMs.