Check if a process exists before returning it

gcapizzi · danail-branekov · estesp · commit d47ee95a6379 · 2020-10-23T11:06:03.000-04:00
Fixes #4632. Signed-off-by: Giuseppe Capizzi <gcapizzi@pivotal.io> Co-authored-by: Danail Branekov <danailster@gmail.com> (cherry picked from commit 8eda32e)
diff --git a/container_linux_test.go b/container_linux_test.go
@@ -940,6 +940,73 @@ func TestContainerAttachProcess(t *testing.T) {
 	<-status
 }
 
+func TestContainerLoadUnexistingProcess(t *testing.T) {
+	t.Parallel()
+
+	if runtime.GOOS == "windows" {
+		// On windows, closing the write side of the pipe closes the read
+		// side, sending an EOF to it and preventing reopening it.
+		// Hence this test will always fails on windows
+		t.Skip("invalid logic on windows")
+	}
+
+	client, err := newClient(t, address)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer client.Close()
+
+	var (
+		image       Image
+		ctx, cancel = testContext(t)
+		id          = t.Name()
+	)
+	defer cancel()
+
+	image, err = client.GetImage(ctx, testImage)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	container, err := client.NewContainer(ctx, id, WithNewSnapshot(id, image), WithNewSpec(oci.WithImageConfig(image), withProcessArgs("sleep", "100")))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer container.Delete(ctx, WithSnapshotCleanup)
+
+	// creating IO early for easy resource cleanup
+	direct, err := newDirectIO(ctx, false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer direct.Delete()
+
+	task, err := container.NewTask(ctx, empty())
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer task.Delete(ctx)
+
+	status, err := task.Wait(ctx)
+	if err != nil {
+		t.Error(err)
+	}
+
+	if err := task.Start(ctx); err != nil {
+		t.Fatal(err)
+	}
+
+	if _, err = task.LoadProcess(ctx, "this-process-does-not-exist", direct.IOAttach); err == nil {
+		t.Fatal("an error should have occurred when loading a process that does not exist")
+	}
+
+	if err := task.Kill(ctx, syscall.SIGKILL); err != nil {
+		t.Error(err)
+	}
+
+	<-status
+}
+
 func TestContainerUserID(t *testing.T) {
 	t.Parallel()
 
diff --git a/runtime/v2/shim.go b/runtime/v2/shim.go
@@ -430,10 +430,14 @@ func (s *shim) Stats(ctx context.Context) (*ptypes.Any, error) {
 }
 
 func (s *shim) Process(ctx context.Context, id string) (runtime.Process, error) {
-	return &process{
+	p := &process{
 		id:   id,
 		shim: s,
-	}, nil
+	}
+	if _, err := p.State(ctx); err != nil {
+		return nil, err
+	}
+	return p, nil
 }
 
 func (s *shim) State(ctx context.Context) (runtime.State, error) {
