mlxsw: spectrum_switchdev: Do not leak RIFs when removing bridge

When a bridge device is removed, the VLANs are flushed from each
configured port. This causes the ports to decrement the reference count
on the associated FIDs (filtering identifier). If the reference count of
a FID is 1 and it has a RIF (router interface), then this RIF is
destroyed.

However, if no port is member in the VLAN for which a RIF exists, then
the RIF will continue to exist after the removal of the bridge. To
reproduce:

# ip link add name br0 type bridge vlan_filtering 1
# ip link set dev swp1 master br0
# ip link add link br0 name br0.10 type vlan id 10
# ip address add 192.0.2.0/24 dev br0.10
# ip link del dev br0

The RIF associated with br0.10 continues to exist.

Fix this by iterating over all the bridge device uppers when it is
destroyed and take care of destroying their RIFs.

Fixes: 99f44bb3 ("mlxsw: spectrum: Enable L3 interfaces on top of bridge devices")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -414,6 +414,8 @@ mlxsw_sp_netdevice_ipip_ul_event(struct mlxsw_sp *mlxsw_sp,
 void
 mlxsw_sp_port_vlan_router_leave(struct mlxsw_sp_port_vlan *mlxsw_sp_port_vlan);
 void mlxsw_sp_rif_destroy(struct mlxsw_sp_rif *rif);
+void mlxsw_sp_rif_destroy_by_dev(struct mlxsw_sp *mlxsw_sp,
+				 struct net_device *dev);
 
 /* spectrum_kvdl.c */
 enum mlxsw_sp_kvdl_entry_type {

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

@@ -6234,6 +6234,17 @@ void mlxsw_sp_rif_destroy(struct mlxsw_sp_rif *rif)
 	mlxsw_sp_vr_put(mlxsw_sp, vr);
 }
 
+void mlxsw_sp_rif_destroy_by_dev(struct mlxsw_sp *mlxsw_sp,
+				 struct net_device *dev)
+{
+	struct mlxsw_sp_rif *rif;
+
+	rif = mlxsw_sp_rif_find_by_dev(mlxsw_sp, dev);
+	if (!rif)
+		return;
+	mlxsw_sp_rif_destroy(rif);
+}
+
 static void
 mlxsw_sp_rif_subport_params_init(struct mlxsw_sp_rif_params *params,
 				 struct mlxsw_sp_port_vlan *mlxsw_sp_port_vlan)

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

@@ -127,6 +127,24 @@ bool mlxsw_sp_bridge_device_is_offloaded(const struct mlxsw_sp *mlxsw_sp,
 	return !!mlxsw_sp_bridge_device_find(mlxsw_sp->bridge, br_dev);
 }
 
+static int mlxsw_sp_bridge_device_upper_rif_destroy(struct net_device *dev,
+						    void *data)
+{
+	struct mlxsw_sp *mlxsw_sp = data;
+
+	mlxsw_sp_rif_destroy_by_dev(mlxsw_sp, dev);
+	return 0;
+}
+
+static void mlxsw_sp_bridge_device_rifs_destroy(struct mlxsw_sp *mlxsw_sp,
+						struct net_device *dev)
+{
+	mlxsw_sp_rif_destroy_by_dev(mlxsw_sp, dev);
+	netdev_walk_all_upper_dev_rcu(dev,
+				      mlxsw_sp_bridge_device_upper_rif_destroy,
+				      mlxsw_sp);
+}
+
 static struct mlxsw_sp_bridge_device *
 mlxsw_sp_bridge_device_create(struct mlxsw_sp_bridge *bridge,
 			      struct net_device *br_dev)
@@ -165,6 +183,8 @@ static void
 mlxsw_sp_bridge_device_destroy(struct mlxsw_sp_bridge *bridge,
 			       struct mlxsw_sp_bridge_device *bridge_device)
 {
+	mlxsw_sp_bridge_device_rifs_destroy(bridge->mlxsw_sp,
+					    bridge_device->dev);
 	list_del(&bridge_device->list);
 	if (bridge_device->vlan_enabled)
 		bridge->vlan_enabled_exists = false;