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Subject: Re: KASAN: slab-out-of-bounds Read in bpf_skb_change_proto
To:     syzbot <syzbot+d2d729bdde65dee3eae6@syzkaller.appspotmail.com>,
        ast@kernel.org, davem@davemloft.net, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com
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From:   Daniel Borkmann <daniel@iogearbox.net>
Message-ID: <76483220-226b-bf3c-d529-ea839d6624c6@iogearbox.net>
Date:   Mon, 11 Jun 2018 11:42:58 +0200
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On 06/10/2018 05:27 PM, syzbot wrote:
> Hello,
> 
> syzbot found the following crash on:
> 
> HEAD commit:    a16afaf7928b Merge tag 'for-v4.18' of git://git.kernel.org..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=1338f6bf800000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=314f2150f36c16ca
> dashboard link: https://syzkaller.appspot.com/bug?extid=d2d729bdde65dee3eae6
> compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
> syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=1173381f800000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=171f90cf800000
> 
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+d2d729bdde65dee3eae6@syzkaller.appspotmail.com

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