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Subject: Re: KASAN: slab-out-of-bounds Read in bpf_skb_change_head
To:     syzbot <syzbot+567faa843005dda30737@syzkaller.appspotmail.com>,
        ast@kernel.org, davem@davemloft.net, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com
References: <0000000000009920d3056e8d57a9@google.com>
From:   Daniel Borkmann <daniel@iogearbox.net>
Message-ID: <3db1d6a4-1059-fec7-00c7-77d26fd5b3c2@iogearbox.net>
Date:   Thu, 14 Jun 2018 01:01:44 +0200
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On 06/14/2018 12:17 AM, syzbot wrote:
> Hello,
> 
> syzbot found the following crash on:
> 
> HEAD commit:    75d4e704fa8d netdev-FAQ: clarify DaveM's position for stab..
> git tree:       bpf-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=16bd21af800000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=a601a80fec461d44
> dashboard link: https://syzkaller.appspot.com/bug?extid=567faa843005dda30737
> compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
> syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=1039185f800000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=11e85cff800000
> 
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+567faa843005dda30737@syzkaller.appspotmail.com

#syz fix: bpf: reject passing modified ctx to helper functions