unregister_netdevice: waiting for DEV to become free (2)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    1236568ee3cb Merge tag 'gpio-v4.18-3' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=135f47e0400000
kernel config:  https://syzkaller.appspot.com/x/.config?x=152cb8ccd35b1f70
dashboard link: https://syzkaller.appspot.com/bug?extid=30209ea299c09d8785c9
compiler:       gcc (GCC) 8.0.1 20180413 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+30209ea299c09d8785c9@xxxxxxxxxxxxxxxxxxxxxxxxx

Invalid argument reading file caps for /root/syz-executor5
Invalid argument reading file caps for /root/syz-executor5
Invalid argument reading file caps for /root/syz-executor5
Invalid argument reading file caps for /root/syz-executor5
Invalid argument reading file caps for /root/syz-executor5
unregister_netdevice: waiting for ip6tnl0 to become free. Usage count = 7
Invalid argument reading file caps for /root/syz-executor5
Invalid argument reading file caps for /root/syz-executor5
Invalid argument reading file caps for /root/syz-executor5
Invalid argument reading file caps for /root/syz-executor5
Invalid argument reading file caps for /root/syz-executor5


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