Hello,

syzbot has tested the proposed patch and the reproducer did not trigger  
crash:

Reported-and-tested-by:  
syzbot+749d9d87c294c00ca856@syzkaller.appspotmail.com

Note: the tag will also help syzbot to understand when the bug is fixed.

Tested on net-next commit
1ec010e705934c8acbe7dbf31afc81e60e3d828b (Fri Feb 16 10:03:07 2018 +0000)
tun: export flags, uid, gid, queue information over netlink

compiler: gcc (GCC) 7.1.1 20170620
Patch is attached.
Kernel config is attached.


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