Fix integer overflow in nmreq_copyin
Fix integer overflow in nmreq_copyin

An unsanitized field in an option could be abused, causing an integer
overflow followed by kernel memory corruption. This might be used
to escape jails/containers.

Reported by: Reno Robert and Lucas Leong (@_wmliang_) of Trend Micro Zero Day Initiative
Security: CVE-2022-23085

luigirizzo/netmap,luigirizzo/netmap,luigirizzo/netmap,luigirizzo/netmap,luigirizzo/netmap