mlxsw: spectrum_router: Veto unsupported RIF MAC addresses

On NETDEV_PRE_CHANGEADDR, if the change is related to a RIF interface,
verify that it satisfies the criterion that all RIF interfaces have the
same MAC address prefix, as indicated by mlxsw_sp.mac_mask.

Additionally, besides explicit address changes, check that the address
of an interface for which a RIF is about to be added matches the
required pattern as well.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/spectrum.c

@@ -5334,7 +5334,9 @@ static int mlxsw_sp_netdevice_event(struct notifier_block *nb,
 	else if (mlxsw_sp_netdev_is_ipip_ul(mlxsw_sp, dev))
 		err = mlxsw_sp_netdevice_ipip_ul_event(mlxsw_sp, dev,
 						       event, ptr);
-	else if (event == NETDEV_CHANGEADDR || event == NETDEV_CHANGEMTU)
+	else if (event == NETDEV_PRE_CHANGEADDR ||
+		 event == NETDEV_CHANGEADDR ||
+		 event == NETDEV_CHANGEMTU)
 		err = mlxsw_sp_netdevice_router_port_event(dev, event, ptr);
 	else if (mlxsw_sp_is_vrf_event(event, ptr))
 		err = mlxsw_sp_netdevice_vrf_event(dev, event, ptr);

drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c

@@ -6699,6 +6699,33 @@ static int mlxsw_sp_inetaddr_macvlan_event(struct net_device *macvlan_dev,
 	return 0;
 }
 
+static int mlxsw_sp_router_port_check_rif_addr(struct mlxsw_sp *mlxsw_sp,
+					       struct net_device *dev,
+					       const unsigned char *dev_addr,
+					       struct netlink_ext_ack *extack)
+{
+	struct mlxsw_sp_rif *rif;
+	int i;
+
+	/* A RIF is not created for macvlan netdevs. Their MAC is used to
+	 * populate the FDB
+	 */
+	if (netif_is_macvlan(dev))
+		return 0;
+
+	for (i = 0; i < MLXSW_CORE_RES_GET(mlxsw_sp->core, MAX_RIFS); i++) {
+		rif = mlxsw_sp->router->rifs[i];
+		if (rif && rif->dev != dev &&
+		    !ether_addr_equal_masked(rif->dev->dev_addr, dev_addr,
+					     mlxsw_sp->mac_mask)) {
+			NL_SET_ERR_MSG_MOD(extack, "All router interface MAC addresses must have the same prefix");
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
 static int __mlxsw_sp_inetaddr_event(struct net_device *dev,
 				     unsigned long event,
 				     struct netlink_ext_ack *extack)
@@ -6760,6 +6787,11 @@ int mlxsw_sp_inetaddr_valid_event(struct notifier_block *unused,
 	if (!mlxsw_sp_rif_should_config(rif, dev, event))
 		goto out;
 
+	err = mlxsw_sp_router_port_check_rif_addr(mlxsw_sp, dev, dev->dev_addr,
+						  ivi->extack);
+	if (err)
+		goto out;
+
 	err = __mlxsw_sp_inetaddr_event(dev, event, ivi->extack);
 out:
 	return notifier_from_errno(err);
@@ -6841,6 +6873,11 @@ int mlxsw_sp_inet6addr_valid_event(struct notifier_block *unused,
 	if (!mlxsw_sp_rif_should_config(rif, dev, event))
 		goto out;
 
+	err = mlxsw_sp_router_port_check_rif_addr(mlxsw_sp, dev, dev->dev_addr,
+						  i6vi->extack);
+	if (err)
+		goto out;
+
 	err = __mlxsw_sp_inetaddr_event(dev, event, i6vi->extack);
 out:
 	return notifier_from_errno(err);
@@ -6914,6 +6951,16 @@ mlxsw_sp_router_port_change_event(struct mlxsw_sp *mlxsw_sp,
 	return err;
 }
 
+static int mlxsw_sp_router_port_pre_changeaddr_event(struct mlxsw_sp_rif *rif,
+			    struct netdev_notifier_pre_changeaddr_info *info)
+{
+	struct netlink_ext_ack *extack;
+
+	extack = netdev_notifier_info_to_extack(&info->info);
+	return mlxsw_sp_router_port_check_rif_addr(rif->mlxsw_sp, rif->dev,
+						   info->dev_addr, extack);
+}
+
 int mlxsw_sp_netdevice_router_port_event(struct net_device *dev,
 					 unsigned long event, void *ptr)
 {
@@ -6932,6 +6979,8 @@ int mlxsw_sp_netdevice_router_port_event(struct net_device *dev,
 	case NETDEV_CHANGEMTU: /* fall through */
 	case NETDEV_CHANGEADDR:
 		return mlxsw_sp_router_port_change_event(mlxsw_sp, rif);
+	case NETDEV_PRE_CHANGEADDR:
+		return mlxsw_sp_router_port_pre_changeaddr_event(rif, ptr);
 	}
 
 	return 0;