net: dev_addr_init() fix

commit f001fde5
(net: introduce a list of device addresses dev_addr_list (v6))
added one regression Vegard Nossum found in its testings.

With kmemcheck help, Vegard found some uninitialized memory
was read and reported to user, potentialy leaking kernel data.
( thread can be found on http://lkml.org/lkml/2009/5/30/177 )

dev_addr_init() incorrectly uses sizeof() operator. We were
initializing one byte instead of MAX_ADDR_LEN bytes.
Reported-by: NVegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Acked-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/core/dev.c

@@ -3655,8 +3655,8 @@ static int dev_addr_init(struct net_device *dev)
 	/* rtnl_mutex must be held here */
 
 	INIT_LIST_HEAD(&dev->dev_addr_list);
-	memset(addr, 0, sizeof(*addr));
-	err = __hw_addr_add(&dev->dev_addr_list, NULL, addr, sizeof(*addr),
+	memset(addr, 0, sizeof(addr));
+	err = __hw_addr_add(&dev->dev_addr_list, NULL, addr, sizeof(addr),
 			    NETDEV_HW_ADDR_T_LAN);
 	if (!err) {
 		/*