bonding: fix NULL pointer deref in startup processing

	Fix the "are we creating a duplicate" check to not compare
the name if the name is NULL (meaning that the system should select
a name).  Bug reported by Benny Amorsen <benny+usenet@amorsen.dk>.

Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 65c7eba..81b4574 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -4896,14 +4896,16 @@
 	down_write(&bonding_rwsem);
 
 	/* Check to see if the bond already exists. */
-	list_for_each_entry_safe(bond, nxt, &bond_dev_list, bond_list)
-		if (strnicmp(bond->dev->name, name, IFNAMSIZ) == 0) {
-			printk(KERN_ERR DRV_NAME
+	if (name) {
+		list_for_each_entry_safe(bond, nxt, &bond_dev_list, bond_list)
+			if (strnicmp(bond->dev->name, name, IFNAMSIZ) == 0) {
+				printk(KERN_ERR DRV_NAME
 			       ": cannot add bond %s; it already exists\n",
-			       name);
-			res = -EPERM;
-			goto out_rtnl;
-		}
+				       name);
+				res = -EPERM;
+				goto out_rtnl;
+			}
+	}
 
 	bond_dev = alloc_netdev(sizeof(struct bonding), name ? name : "",
 				ether_setup);