On Mon, 13 Aug 2018 21:40:03 -0700 syzbot wrote:

Hello,

syzbot found the following crash on:

HEAD commit:    78cbac647e61 Merge branch 'ip-faster-in-order-IP-fragments'
git tree:       net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=14df4828400000
kernel config:  https://syzkaller.appspot.com/x/.config?x=9100338df26ab75
dashboard link: https://syzkaller.appspot.com/bug?extid=eaaf6c4a6a8cb1869d86
compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=13069ad2400000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+eaaf6c4a6a8cb1869d86@syzkaller.appspotmail.com

#syz invalid

Hard to track down what fixed this, but the lockdep splat is mixing up
locks from two different hashtables, so there was never a real issue
here.