net: check before dereferencing netdev_ops during busy poll

From: Matteo Croce
Date: Fri Jun 28 2019 - 12:35:38 EST


Hi,

Is there any reason for this panic fix not being applied in stable?

https://lore.kernel.org/netdev/20180313053248.13654-1-jelsasser@xxxxxxxxxxx/T/

It seems that linux 4.9.184 has the bug too.

Regards,
--
Matteo Croce
per aspera ad upstream