[PATCH] e1000: Fix invalid memory reference

Fix an invalid memory reference in the e1000 driver which would cause
kernel panic.
Signed-off-by: NKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Cc: Jeb Cramer <cramerj@intel.com>
Cc: John Ronciak <john.ronciak@intel.com>
Cc: Ganesh Venkatesan <ganesh.venkatesan@intel.com>
Cc: Jeff Garzik <jgarzik@pobox.com>
Acked-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

drivers/net/e1000/e1000_param.c

@@ -545,7 +545,7 @@ e1000_check_fiber_options(struct e1000_adapter *adapter)
 static void __devinit
 e1000_check_copper_options(struct e1000_adapter *adapter)
 {
-	int speed, dplx;
+	int speed, dplx, an;
 	int bd = adapter->bd_number;
 
 	{ /* Speed */
@@ -641,8 +641,12 @@ e1000_check_copper_options(struct e1000_adapter *adapter)
 					 .p = an_list }}
 		};
 
-		int an = AutoNeg[bd];
-		e1000_validate_option(&an, &opt, adapter);
+		if (num_AutoNeg > bd) {
+			an = AutoNeg[bd];
+			e1000_validate_option(&an, &opt, adapter);
+		} else {
+			an = opt.def;
+		}
 		adapter->hw.autoneg_advertised = an;
 	}