pcnet32: Read buffer overflow

An `options[cards_found]' that equals `sizeof(options_mapping)' is already beyond
the array.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/pcnet32.c b/drivers/net/pcnet32.c
index a646a44..23e1a07 100644
--- a/drivers/net/pcnet32.c
+++ b/drivers/net/pcnet32.c
@@ -1839,7 +1839,7 @@
 	lp->chip_version = chip_version;
 	lp->msg_enable = pcnet32_debug;
 	if ((cards_found >= MAX_UNITS)
-	    || (options[cards_found] > sizeof(options_mapping)))
+	    || (options[cards_found] >= sizeof(options_mapping)))
 		lp->options = PCNET32_PORT_ASEL;
 	else
 		lp->options = options_mapping[options[cards_found]];