macvlan: do proper cleanup in macvlan_common_newlink() V2

Fixes possible memory leak.

Signed-off-by: Jiri Pirko <[e-mail]>
Acked-by: Patrick McHardy <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/macvlan.c

···
 
 	err = register_netdevice(dev);
 	if (err < 0)
-		return err;
+		goto destroy_port;
 
 	list_add_tail(&vlan->list, &port->vlans);
 	netif_stacked_transfer_operstate(lowerdev, dev);
+
 	return 0;
+
+destroy_port:
+	if (list_empty(&port->vlans))
+		macvlan_port_destroy(lowerdev);
+
+	return err;
 }
 EXPORT_SYMBOL_GPL(macvlan_common_newlink);