Re: KASAN: slab-out-of-bounds Read in fbcon_get_font

On 05/12/19 11:16, Dmitry Vyukov wrote:

On Thu, Dec 5, 2019 at 11:13 AM Paolo Bonzini [off-list ref] wrote:

quoted

On 04/12/19 22:41, syzbot wrote:

quoted

syzbot has bisected this bug to:

commit 2de50e9674fc4ca3c6174b04477f69eb26b4ee31
Author: Russell Currey [off-list ref]
Date:   Mon Feb 8 04:08:20 2016 +0000

    powerpc/powernv: Remove support for p5ioc2

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x7a042ae00000
start commit:   76bb8b05 Merge tag 'kbuild-v5.5' of
git://git.kernel.org/p..
git tree:       upstream
final crash:    https://syzkaller.appspot.com/x/report.txt?x7a042ae00000
console output: https://syzkaller.appspot.com/x/log.txt?x7a042ae00000
kernel config:  https://syzkaller.appspot.com/x/.config?xÝ226651cb0f364b
dashboard link:
https://syzkaller.appspot.com/bug?extidD55ca3b3291de891abc
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x181edae00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x5cbb7ae00000

Reported-by: syzbot+4455ca3b3291de891abc@syzkaller.appspotmail.com
Fixes: 2de50e9674fc ("powerpc/powernv: Remove support for p5ioc2")

For information about bisection process see:
https://goo.gl/tpsmEJ#bisection

Why is everybody being CC'd, even if the bug has nothing to do with the
person's subsystem?

The To list should be intersection of 2 groups of emails: result of
get_maintainers.pl on the file identified as culprit in the crash
message + emails extracted from the bisected to commit.

Ah, and because the machine is a KVM guest, kvm_wait appears in a lot of
backtrace and I get to share syzkaller's joy every time. :)

This bisect result is bogus, though Tetsuo found the bug anyway.
Perhaps you can exclude commits that only touch architectures other than
x86?

Paolo