Fix root daemon access when running with embedded root daemon

When the user daemon runs with an embedded root daemon (e.g., in Docker
mode), calls to RootDaemonVersion and withRootDaemon failed because they
didn't account for the in-process root session. RootDaemonVersion now
returns the local version directly, and withRootDaemon delegates to the
session's WithRootClient when a session is available.

Signed-off-by: Thomas Hallgren <thomas@tada.se>

Author: thallgren

pkg/client/userd/daemon/grpc.go

@@ -448,6 +448,9 @@ func (s *service) TrafficManagerVersion(ctx context.Context, _ *empty.Empty) (vi
 }
 
 func (s *service) RootDaemonVersion(ctx context.Context, empty *empty.Empty) (vi *common.VersionInfo, err error) {
+	if s.rootSessionInProc {
+		return client.VersionInfo(ctx), nil
+	}
 	err = s.withRootDaemon(ctx, func(ctx context.Context, rd daemon.DaemonClient) error {
 		vi, err = rd.Version(s, empty)
 		return err
@@ -631,6 +634,12 @@ func (s *service) RerouteRemotePort(ctx context.Context, request *daemon.Reroute
 }
 
 func (s *service) withRootDaemon(ctx context.Context, f func(ctx context.Context, daemonClient daemon.DaemonClient) error) error {
+	s.sessionLock.RLock()
+	defer s.sessionLock.RUnlock()
+	if s.session != nil {
+		return s.session.WithRootClient(ctx, f)
+	}
+
 	if s.rootSessionInProc {
 		return status.Error(codes.Unavailable, "root daemon is embedded")
 	}