Fix SIGURG Handling

internal/app/starter/master_linux.go

@@ -123,7 +123,9 @@ func Master(rpcSocket, masterSocket int, containerPid int, e *engine.Engine) {
 	// we could receive signal from child with CreateContainer call so we
 	// set the signal handler earlier to queue signals until MonitorContainer
 	// is called to handle them
-	signals := make(chan os.Signal, 1)
+	// Use a channel size of two here, since we may receive SIGURG, which is
+	// used for non-cooperative goroutine preemption starting with Go 1.14.
+	signals := make(chan os.Signal, 2)
 	signal.Notify(signals)
 
 	ctx := context.TODO()

internal/pkg/runtime/engine/fakeroot/engine_linux.go

@@ -261,6 +261,11 @@ func (e *EngineOperations) MonitorContainer(pid int, signals chan os.Signal) (sy
 				continue
 			}
 			return status, nil
+		case syscall.SIGURG:
+			// Ignore SIGURG, which is used for non-cooperative goroutine
+			// preemption starting with Go 1.14. For more information, see
+			// https://github.com/golang/go/issues/24543.
+			break
 		default:
 			if err := syscall.Kill(pid, s.(syscall.Signal)); err != nil {
 				return status, fmt.Errorf("interrupted by signal %s", s.String())

internal/pkg/runtime/engine/oci/monitor_linux.go

@@ -36,6 +36,11 @@ func (e *EngineOperations) MonitorContainer(pid int, signals chan os.Signal) (sy
 				continue
 			}
 			return status, nil
+		case syscall.SIGURG:
+			// Ignore SIGURG, which is used for non-cooperative goroutine
+			// preemption starting with Go 1.14. For more information, see
+			// https://github.com/golang/go/issues/24543.
+			break
 		default:
 			if err := syscall.Kill(pid, s.(syscall.Signal)); err != nil {
 				return status, fmt.Errorf("interrupted by signal %s", s.String())

internal/pkg/runtime/engine/singularity/monitor_linux.go

@@ -48,6 +48,11 @@ func (e *EngineOperations) MonitorContainer(pid int, signals chan os.Signal) (sy
 				continue
 			}
 			return status, nil
+		case syscall.SIGURG:
+			// Ignore SIGURG, which is used for non-cooperative goroutine
+			// preemption starting with Go 1.14. For more information, see
+			// https://github.com/golang/go/issues/24543.
+			break
 		default:
 			if e.EngineConfig.GetSignalPropagation() {
 				if err := syscall.Kill(pid, s.(syscall.Signal)); err != nil {

internal/pkg/runtime/engine/singularity/process_linux.go

@@ -56,7 +56,9 @@ const defaultShell = "/bin/sh"
 func (e *EngineOperations) StartProcess(masterConn net.Conn) error {
 	// Manage all signals.
 	// Queue them until they're ready to be handled below.
-	signals := make(chan os.Signal, 1)
+	// Use a channel size of two here, since we may receive SIGURG, which is
+	// used for non-cooperative goroutine preemption starting with Go 1.14.
+	signals := make(chan os.Signal, 2)
 	signal.Notify(signals)
 
 	if err := e.runFuseDrivers(true, -1); err != nil {
@@ -244,6 +246,11 @@ func (e *EngineOperations) StartProcess(masterConn net.Conn) error {
 						statusChan <- status
 					}
 				}
+			case syscall.SIGURG:
+				// Ignore SIGURG, which is used for non-cooperative goroutine
+				// preemption starting with Go 1.14. For more information, see
+				// https://github.com/golang/go/issues/24543.
+				break
 			default:
 				signal := s.(syscall.Signal)
 				// EPERM and EINVAL are deliberately ignored because they can't be