Hello,

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

Reported-and-tested-by:  
syzbot+6e6a5ec8de31a94cd015@syzkaller.appspotmail.com

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

Tested on  
https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git/master  
commit
617aebe6a97efa539cc4b8a52adccd89596e6be0 (Sun Feb 4 00:25:42 2018 +0000)
Merge tag 'usercopy-v4.16-rc1' of  
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

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


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