Handle vfkit connection in goroutine & close old one on new connection

Moved AcceptVfkit handling into a goroutine to prevent blocking the listener and ensure responsiveness.
Added logic to cancel any existing context before accepting a new connection.

Author: vyasgun

cmd/crc/cmd/daemon.go

@@ -2,6 +2,7 @@ package cmd
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -209,11 +210,20 @@ func run(configuration *types.Configuration) error {
 	}()
 
 	go func() {
+		var ctx context.Context
+		var cancel context.CancelFunc
 		for {
-			_, err := unixgramListener(vn)
+			conn, err := setupUnixgramListener()
 			if err != nil && !errors.Is(err, net.ErrClosed) {
 				logging.Errorf("unixgramListener error: %v", err)
 			}
+			if cancel != nil {
+				logging.Warnf("New connection from %s. Closing old connection", conn.LocalAddr().String())
+				cancel()
+			}
+
+			ctx, cancel = context.WithCancel(context.Background())
+			go handleUnixgramConnection(ctx, vn, conn)
 			time.Sleep(1 * time.Second)
 		}
 	}()

cmd/crc/cmd/daemon_darwin.go

@@ -33,19 +33,26 @@ func httpListener() (net.Listener, error) {
 	return ln, nil
 }
 
-func unixgramListener(vn *virtualnetwork.VirtualNetwork) (*net.UnixConn, error) {
+func setupUnixgramListener() (net.Conn, error) {
 	_ = os.Remove(constants.UnixgramSocketPath)
 	conn, err := transport.ListenUnixgram(fmt.Sprintf("unixgram://%v", constants.UnixgramSocketPath))
 	if err != nil {
-		return conn, errors.Wrap(err, "failed to listen unixgram")
+		return nil, errors.Wrap(err, "failed to listen unixgram")
 	}
-	logging.Infof("listening on %s:", constants.UnixgramSocketPath)
+	logging.Infof("listening on %s", constants.UnixgramSocketPath)
 	vfkitConn, err := transport.AcceptVfkit(conn)
 	if err != nil {
-		return conn, errors.Wrap(err, "failed to accept vfkit connection")
+		return nil, errors.Wrap(err, "failed to accept vfkit connection")
 	}
-	err = vn.AcceptVfkit(context.Background(), vfkitConn)
-	return conn, errors.Wrap(err, "failed to accept vfkit connection")
+	return vfkitConn, nil
+}
+
+func handleUnixgramConnection(ctx context.Context, vn *virtualnetwork.VirtualNetwork, vfkitConn net.Conn) {
+	defer vfkitConn.Close()
+	if err := vn.AcceptVfkit(ctx, vfkitConn); err != nil {
+		logging.Errorf("failed to accept vfkit connection: %v", err)
+	}
+	logging.Debugf("Closed connection from %s", vfkitConn.LocalAddr().String())
 }
 
 func checkIfDaemonIsRunning() (bool, error) {

cmd/crc/cmd/daemon_linux.go

@@ -1,6 +1,7 @@
 package cmd
 
 import (
+	"context"
 	"fmt"
 	"net"
 	"os"
@@ -125,10 +126,12 @@ func httpListener() (net.Listener, error) {
 	return ln, nil
 }
 
-func unixgramListener(_ *virtualnetwork.VirtualNetwork) (*net.UnixConn, error) {
+func setupUnixgramListener() (net.Conn, error) {
 	return nil, nil
 }
 
+func handleUnixgramConnection(_ context.Context, _ *virtualnetwork.VirtualNetwork, _ net.Conn) {}
+
 func startupDone() {
 	_, _ = daemon.SdNotify(false, daemon.SdNotifyReady)
 }

cmd/crc/cmd/daemon_windows.go

@@ -5,7 +5,6 @@ import (
 
 	"github.com/Microsoft/go-winio"
 	"github.com/containers/gvisor-tap-vsock/pkg/transport"
-	"github.com/containers/gvisor-tap-vsock/pkg/virtualnetwork"
 	"github.com/crc-org/crc/v2/pkg/crc/constants"
 	"github.com/crc-org/crc/v2/pkg/crc/logging"
 )
@@ -36,9 +35,11 @@ func checkIfDaemonIsRunning() (bool, error) {
 	return checkDaemonVersion()
 }
 
-func unixgramListener(_ *virtualnetwork.VirtualNetwork) (*net.UnixConn, error) {
+func setupUnixgramListener() (net.Conn, error) {
 	return nil, nil
 }
 
+func handleUnixgramConnection(_ context.Context, _ *virtualnetwork.VirtualNetwork, _ net.Conn) {}
+
 func startupDone() {
 }