fix(ipc): Add timeout to AwaitMessage to prevent indefinite blocking

- Add IPCAcceptTimeout (60s) and IPCReadTimeout (10s) to prevent
  orphaned processes when counterpart never connects
- Fix closure bug in executeHooksConcurrently using wrong loop variable
- Fix isRunning() using annotType instead of annotHypervisor
- Add tests for timeout and wrong message handling

Signed-off-by: Aman-Cool <aman017102007@gmail.com>

Author: Aman-Cool

pkg/unikontainers/ipc.go

@@ -41,6 +41,12 @@ const (
 	maxRetries               = 50
 	waitTime                 = 5 * time.Millisecond
 	FromReexec               = true
+	// IPCAcceptTimeout is the maximum time to wait for a connection on the IPC socket.
+	// This prevents processes from hanging indefinitely if the counterpart never connects
+	// (e.g., due to containerd restart, node pressure, or orchestration failures).
+	IPCAcceptTimeout = 60 * time.Second
+	// IPCReadTimeout is the maximum time to wait for reading a message after connection.
+	IPCReadTimeout = 10 * time.Second
 )
 
 func getSockAddr(dir string, name string) string {
@@ -145,27 +151,48 @@ func createListener(socketAddress string, mustBeValid bool) (*net.UnixListener,
 	return listener, nil
 }
 
-// awaitMessage opens a new connection to socketAddress
-// and waits for a given message
+// AwaitMessage waits for a connection on the listener and reads an expected message.
+// It uses timeouts to prevent indefinite blocking if the counterpart process
+// never connects (e.g., due to orchestration failures, crashes, or restarts).
 func AwaitMessage(listener *net.UnixListener, expectedMessage IPCMessage) error {
+	// Set accept deadline to prevent indefinite blocking.
+	// This is critical for preventing orphaned processes when urunc start
+	// never runs after urunc create, or when reexec fails silently.
+	if err := listener.SetDeadline(time.Now().Add(IPCAcceptTimeout)); err != nil {
+		return fmt.Errorf("failed to set listener deadline: %w", err)
+	}
+
 	conn, err := listener.AcceptUnix()
 	if err != nil {
-		return err
+		var netErr net.Error
+		if errors.As(err, &netErr) && netErr.Timeout() {
+			return fmt.Errorf("timeout waiting for IPC connection (waited %v): counterpart process may have failed or not started", IPCAcceptTimeout)
+		}
+		return fmt.Errorf("failed to accept connection: %w", err)
 	}
 	defer func() {
-		err = conn.Close()
-		if err != nil {
-			logrus.WithError(err).Error("failed to close connection")
+		if closeErr := conn.Close(); closeErr != nil {
+			logrus.WithError(closeErr).Error("failed to close connection")
 		}
 	}()
+
+	// Set read deadline to prevent hanging on slow or stuck writers
+	if err := conn.SetReadDeadline(time.Now().Add(IPCReadTimeout)); err != nil {
+		return fmt.Errorf("failed to set read deadline: %w", err)
+	}
+
 	buf := make([]byte, len(expectedMessage))
 	n, err := conn.Read(buf)
 	if err != nil {
+		var netErr net.Error
+		if errors.As(err, &netErr) && netErr.Timeout() {
+			return fmt.Errorf("timeout reading IPC message (waited %v): counterpart process may be stuck", IPCReadTimeout)
+		}
 		return fmt.Errorf("failed to read from socket: %w", err)
 	}
 	msg := string(buf[0:n])
 	if msg != string(expectedMessage) {
-		return fmt.Errorf("received unexpected message: %s", msg)
+		return fmt.Errorf("received unexpected message: %s (expected: %s)", msg, expectedMessage)
 	}
 	return nil
 }

pkg/unikontainers/ipc_test.go

@@ -176,3 +176,56 @@ func TestAwaitMessage(t *testing.T) {
 	err = AwaitMessage(listener, expectedMessage)
 	assert.NoError(t, err, "Expected no error in awaiting message")
 }
+
+func TestAwaitMessageTimeout(t *testing.T) {
+	socketAddress := "/tmp/test_await_message_timeout.sock"
+	expectedMessage := ReexecStarted
+
+	listener, err := createListener(socketAddress, true)
+	if err != nil {
+		t.Fatalf("Failed to create listener: %v", err)
+	}
+	defer listener.Close()
+
+	// Don't send any message - this should trigger a timeout
+	// Note: For testing, we need shorter timeouts than production.
+	// The actual timeout check is that it returns an error containing "timeout"
+	// rather than blocking forever.
+
+	// Set a shorter deadline for testing purposes
+	listener.SetDeadline(time.Now().Add(100 * time.Millisecond))
+
+	err = AwaitMessage(listener, expectedMessage)
+	assert.Error(t, err, "Expected timeout error when no connection arrives")
+	assert.Contains(t, err.Error(), "timeout", "Expected error message to mention timeout")
+}
+
+func TestAwaitMessageWrongMessage(t *testing.T) {
+	socketAddress := "/tmp/test_await_wrong_message.sock"
+	expectedMessage := ReexecStarted
+	wrongMessage := StartExecve
+
+	listener, err := createListener(socketAddress, true)
+	if err != nil {
+		t.Fatalf("Failed to create listener: %v", err)
+	}
+	defer listener.Close()
+
+	go func() {
+		conn, err := net.Dial("unix", socketAddress)
+		if err != nil {
+			t.Errorf("Failed to dial connection: %v", err)
+		}
+		defer conn.Close()
+
+		// Send wrong message
+		_, err = conn.Write([]byte(wrongMessage))
+		if err != nil {
+			t.Errorf("Failed to send message: %v", err)
+		}
+	}()
+
+	err = AwaitMessage(listener, expectedMessage)
+	assert.Error(t, err, "Expected error for unexpected message")
+	assert.Contains(t, err.Error(), "unexpected message", "Expected error to mention unexpected message")
+}

pkg/unikontainers/unikontainers.go

@@ -753,8 +753,8 @@ func (u *Unikontainer) executeHooksConcurrently(name string, hooks []specs.Hook,
 				uniklog.WithFields(logrus.Fields{
 					"id":    u.State.ID,
 					"name":  name,
-					"path":  hooks[i].Path,
-					"args":  hooks[i].Args,
+					"path":  h.Path,
+					"args":  h.Args,
 					"error": err,
 				}).Error("Executing hook failed")
 				errChan <- err
@@ -1121,7 +1121,7 @@ func (u *Unikontainer) SendMessage(message IPCMessage) error {
 
 // isRunning returns true if the PID is alive or hedge.ListVMs returns our containerID
 func (u *Unikontainer) isRunning() bool {
-	vmmType := hypervisors.VmmType(u.State.Annotations[annotType])
+	vmmType := hypervisors.VmmType(u.State.Annotations[annotHypervisor])
 	if vmmType != hypervisors.HedgeVmm {
 		return syscall.Kill(u.State.Pid, syscall.Signal(0)) == nil
 	}