Re: WARNING: bad usercopy in corrupted (2)

Dmitry Vyukov <[email protected]> Wed, 20 Mar 2019 10:39:59 +0100

Newsgroups	gmane.linux.network,gmane.linux.kernel,gmane.linux.kernel.mm,gmane.linux.network.general
Message-ID	<CACT4Y+a=9DQhgq243k9c6SPiyAhDQG5y2GqT4Da_P97t5n4Brw@mail.gmail.com>

On Wed, Mar 20, 2019 at 1:49 AM syzbot
<[email protected]> wrote:
>
> syzbot has bisected this bug to:
>
> commit b8a51b38e4d4dec3e379d52c0fe1a66827f7cf1e
> Author: Stefano Brivio <[email protected]>
> Date:   Thu Nov 8 11:19:23 2018 +0000
>
>      fou, fou6: ICMP error handlers for FoU and GUE
>
> bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=14a57f83200000
> start commit:   b8a51b38 fou, fou6: ICMP error handlers for FoU and GUE
> git tree:       net-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=12a57f83200000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=c36a72af2123e78a
> dashboard link: https://syzkaller.appspot.com/bug?extid=d89b30c46434c433dbf8
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=170f6a47400000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12e1df7b400000
>
> Reported-by: [email protected]
> Fixes: b8a51b38 ("fou, fou6: ICMP error handlers for FoU and GUE")

That commit caused lots of crashes that look completely differently.
Now all that is fixed. The last crash for this bugs happened 2+ months
ago. So let's just do:

#syz fix: fou: Prevent unbounded recursion in GUE error handler also
with UDP-Lite