[PATCH] rio: fix array checking

Found by an analysis tool and reported to the list. Fix is simple enough

Signed-off-by: Alan Cox <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/char/rio/rioctrl.c

···
 			p->RIOError.Error = COPYIN_FAILED;
 			return -EFAULT;
 		}
-		if (portStats.port >= RIO_PORTS) {
+		if (portStats.port < 0 || portStats.port >= RIO_PORTS) {
 			p->RIOError.Error = PORT_NUMBER_OUT_OF_RANGE;
 			return -ENXIO;
 		}
···
 			p->RIOError.Error = COPYIN_FAILED;
 			return -EFAULT;
 		}
-		if (portStats.port >= RIO_PORTS) {
+		if (portStats.port < 0 || portStats.port >= RIO_PORTS) {
 			p->RIOError.Error = PORT_NUMBER_OUT_OF_RANGE;
 			return -ENXIO;
 		}