proactively clean up leaked vnet and container veths in vm ns before creating new veth pair

Author: QxBytes

network/transparent_vlan_endpointclient_linux.go

@@ -310,6 +310,16 @@ func (client *TransparentVlanEndpointClient) PopulateVM(epInfo *EndpointInfo) er
 		logger.Info("Failed to parse the mac address", zap.String("defaultHostVethHwAddr", defaultHostVethHwAddr))
 	}
 
+	// Proactively clean up any leftover veth interfaces before creating new ones
+	if err := client.netlink.DeleteLink(client.vnetVethName); err != nil {
+		logger.Info("Could not proactively clean up vnet veth (expected if not present)",
+			zap.String("vnetVethName", client.vnetVethName), zap.Error(err))
+	}
+	if err := client.netlink.DeleteLink(client.containerVethName); err != nil {
+		logger.Info("Could not proactively clean up container veth (expected if not present)",
+			zap.String("containerVethName", client.containerVethName), zap.Error(err))
+	}
+
 	// Create veth pair
 	if err = client.netUtilsClient.CreateEndpoint(client.vnetVethName, client.containerVethName, mac); err != nil {
 		return errors.Wrap(err, "failed to create veth pair")

network/transparent_vlan_endpointclient_linux_test.go

@@ -344,7 +344,12 @@ func TestTransparentVlanAddEndpoints(t *testing.T) {
 					set:         defaultSet,
 					deleteNamed: defaultDeleteNamed,
 				},
-				netlink:        netlink.NewMockNetlink(false, ""),
+				netlink: &netlink.MockNetlink{
+					DeleteLinkFn: func(name string) error {
+						// should still succeed
+						return netlink.ErrorMockNetlink
+					},
+				},
 				plClient:       platform.NewMockExecClient(false),
 				netUtilsClient: networkutils.NewNetworkUtils(nl, plc),
 				netioshim:      netio.NewMockNetIO(false, 0),