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Subject: Re: KASAN: slab-out-of-bounds Read in skb_ensure_writable
To:     syzbot <syzbot+e5190cb881d8660fb1a3@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: <47029528-5c56-61a4-9d86-33f1e7ad14d4@iogearbox.net>
Date:   Fri, 8 Jun 2018 11:54:15 +0200
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On 06/04/2018 01:36 AM, syzbot wrote:
> Hello,
> 
> syzbot found the following crash on:
> 
> HEAD commit:    0512e0134582 Merge tag 'xfs-4.17-fixes-3' of git://git.ker..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=14956af7800000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=968b0b23c7854c0b
> dashboard link: https://syzkaller.appspot.com/bug?extid=e5190cb881d8660fb1a3
> compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
> syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=123d9d7b800000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=100329d7800000

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