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Subject: Re: KASAN: slab-out-of-bounds Read in fbcon_get_font
To:     Dmitry Vyukov <dvyukov@google.com>
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From:   Paolo Bonzini <pbonzini@redhat.com>
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Date:   Thu, 5 Dec 2019 12:29:20 +0100
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On 05/12/19 12:27, Dmitry Vyukov wrote:
> Oh, you mean the final bisection crash. Indeed it contains a kvm frame
> and it turns out to be a bug in syzkaller code that indeed
> misattributed it to kvm instead of netfilter.
> Should be fixed now, you may read the commit message for details:
> https://github.com/google/syzkaller/commit/4fb74474cf0af2126be3a8989d770c3947ae9478
> 
> Overall this "making sense out of kernel output" task is the ultimate
> insanity, you may skim through this file to get a taste of amount of
> hardcoding and special corner cases that need to be handled:
> https://github.com/google/syzkaller/blob/master/pkg/report/linux.go
> And this is never done, such "exception from exception corner case"
> things pop up every week. There is always something to shuffle and
> tune. It only keeps functioning due to 500+ test cases for all
> possible insane kernel outputs:
> https://github.com/google/syzkaller/tree/master/pkg/report/testdata/linux/report
> https://github.com/google/syzkaller/tree/master/pkg/report/testdata/linux/guilty
> 
> So thanks for persisting and questioning! We are getting better with
> each new test.

Thanks to you!  I "complain" because I know you're so responsive. :)

Paolo