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Subject: Re: general protection fault in fdb_find_rcu
To:     syzbot <syzbot+017b1f61c82a1c3e7efd@syzkaller.appspotmail.com>,
        bridge@lists.linux-foundation.org, davem@davemloft.net,
        linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
        roopa@cumulusnetworks.com, syzkaller-bugs@googlegroups.com
References: <0000000000004e8a91057e355803@google.com>
From:   Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Message-ID: <663bc6d0-f6ec-796d-54bb-b9afa3c0bce1@cumulusnetworks.com>
Date:   Sun, 30 Dec 2018 13:34:34 +0200
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On 30/12/2018 06:01, syzbot wrote:
> Hello,
> 
> syzbot found the following crash on:
> 
> HEAD commit:    90cadbbf341d Merge git://git.kernel.org/pub/scm/linux/kern..
> git tree:       net-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=1745c69b400000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=9d41c8529d7e7362
> dashboard link: https://syzkaller.appspot.com/bug?extid=017b1f61c82a1c3e7efd
> compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=15babaab400000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14c6142d400000
> 
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+017b1f61c82a1c3e7efd@syzkaller.appspotmail.com
> 

Ah yes, good catch. We've missed this obvious bug during the review.
A patch is on its way, just need to run a few tests.

Cheers,
 Nik