fix: Improve closure of provisioner and agent tailnet dial (#6199)

coderd/coderdtest/coderdtest.go

@@ -396,13 +396,16 @@ func NewProvisionerDaemon(t *testing.T, coderAPI *coderd.API) io.Closer {
 func NewExternalProvisionerDaemon(t *testing.T, client *codersdk.Client, org uuid.UUID, tags map[string]string) io.Closer {
 	echoClient, echoServer := provisionersdk.MemTransportPipe()
 	ctx, cancelFunc := context.WithCancel(context.Background())
+	serveDone := make(chan struct{})
 	t.Cleanup(func() {
 		_ = echoClient.Close()
 		_ = echoServer.Close()
 		cancelFunc()
+		<-serveDone
 	})
 	fs := afero.NewMemMapFs()
 	go func() {
+		defer close(serveDone)
 		err := echo.Serve(ctx, fs, &provisionersdk.ServeOptions{
 			Listener: echoServer,
 		})

coderd/workspaceagents.go

@@ -447,6 +447,8 @@ func (api *API) dialWorkspaceAgentTailnet(r *http.Request, agentID uuid.UUID) (*
 		Logger:    api.Logger.Named("tailnet"),
 	})
 	if err != nil {
+		_ = clientConn.Close()
+		_ = serverConn.Close()
 		return nil, xerrors.Errorf("create tailnet conn: %w", err)
 	}