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Date:   Fri, 4 Jan 2019 11:54:35 +0100
From:   Stefano Brivio <sbrivio@redhat.com>
To:     Dmitry Vyukov <dvyukov@google.com>
Cc:     Willem de Bruijn <willemdebruijn.kernel@gmail.com>,
        Eric Dumazet <eric.dumazet@gmail.com>,
        syzbot <syzbot+4ad25edc7a33e4ab91e0@syzkaller.appspotmail.com>,
        David Miller <davem@davemloft.net>,
        Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Network Development <netdev@vger.kernel.org>,
        syzkaller-bugs <syzkaller-bugs@googlegroups.com>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Subject: Re: kernel panic: stack is corrupted in udp4_lib_lookup2
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On Fri, 4 Jan 2019 11:32:12 +0100
Dmitry Vyukov <dvyukov@google.com> wrote:

> On Thu, Jan 3, 2019 at 10:54 PM Stefano Brivio <sbrivio@redhat.com> wrote:
> >
> > On Thu, 3 Jan 2019 15:15:06 -0600
> > Willem de Bruijn <willemdebruijn.kernel@gmail.com> wrote:
> >  
> > > syzbot generated stack traces with
> > >
> > > [  183.517380]  udpv6_err+0x46/0x60
> > > [  183.520739]  ? __udp6_lib_err+0x1890/0x1890
> > > [  183.525054]  gue6_err_proto_handler+0x199/0x280  
> >
> > Where? I can't find that in any logs linked from the dashboard at
> > https://syzkaller.appspot.com/bug?extid=4ad25edc7a33e4ab91e0 :(  
> 
> Stefano, there are these 4 bugs reported that have similarly looking
> reproducers involving udp sockets and that crash modes that looks like
> stack corruption/overflow:
> 
> https://syzkaller.appspot.com/bug?extid=14005fa30c9a07192934
> https://syzkaller.appspot.com/bug?extid=d14090007dc9ba5fa9b7
> https://syzkaller.appspot.com/bug?extid=137ed32ec9a6d5b0d5fe
> https://syzkaller.appspot.com/bug?id=d5bc3e0c66d200d72216ab343a67c4327e4a3452
> 
> Are these the same bug as this?

Judging from the reproducers for the first three, they seem to be. I
guess I can trigger tests also for those by sending a (sharp)syz
test ... e-mail with the patch to the Reported-by: addresses, right?

And the three reports you pointed out from the pile of corrupted
reports also seem to match, others look unrelated.

-- 
Stefano