eth: reset addr_assign_type if eth_mac_addr() called

If eth_mac_addr() get called, usually if SIOCSIFHWADDR was
used to change the MAC of a ethernet device, reset the
addr_assign_type to NET_ADDR_PERM if the state was
NET_ADDR_RANDOM before. Reset the state since the MAC is
no longer random at least not from the kernel side.

v2: changed to bitops, removed if()

Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ethernet/eth.c

@@ -288,6 +288,8 @@ int eth_mac_addr(struct net_device *dev, void *p)
 	if (!is_valid_ether_addr(addr->sa_data))
 		return -EADDRNOTAVAIL;
 	memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
+	/* if device marked as NET_ADDR_RANDOM, reset it */
+	dev->addr_assign_type &= ~NET_ADDR_RANDOM;
 	return 0;
 }
 EXPORT_SYMBOL(eth_mac_addr);