MFC:	sys/opencrypto/cryptodev.c	1.26
MFC:	sys/opencrypto/cryptodev.c	1.26

Fix bogus check. It was possible to panic the kernel by giving 0 length.
This is actually a local DoS, as every user can use /dev/crypto if there
is crypto hardware in the system and cryptodev.ko is loaded (or compiled
into the kernel).

Reported by:    Mike Tancsa <mike@sentex.net>
Security:	Local DoS on systems with crypto HW and with /dev/crypto available
Approved by:	re (kensmith)

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase