Unmount subpath should only scan the first level dir

pkg/util/mount/fake.go

@@ -32,9 +32,12 @@ type FakeMounter struct {
 	MountCheckErrors map[string]error
 	// Some tests run things in parallel, make sure the mounter does not produce
 	// any golang's DATA RACE warnings.
-	mutex sync.Mutex
+	mutex      sync.Mutex
+	UmountFunc UmountFunc
 }
 
+type UmountFunc func(path string) error
+
 var _ Interface = &FakeMounter{}
 
 const (
@@ -117,6 +120,12 @@ func (f *FakeMounter) Unmount(target string) error {
 	newMountpoints := []MountPoint{}
 	for _, mp := range f.MountPoints {
 		if mp.Path == absTarget {
+			if f.UmountFunc != nil {
+				err := f.UmountFunc(absTarget)
+				if err != nil {
+					return err
+				}
+			}
 			klog.V(5).Infof("Fake mounter: unmounted %s from %s", mp.Device, absTarget)
 			// Don't copy it to newMountpoints
 			continue

pkg/volume/util/subpath/subpath_linux.go

@@ -241,7 +241,8 @@ func doCleanSubPaths(mounter mount.Interface, podDir string, volumeName string)
 			if err = doCleanSubPath(mounter, fullContainerDirPath, filepath.Base(path)); err != nil {
 				return err
 			}
-			return nil
+			// skip subdirs of the volume: it only matters the first level to unmount, otherwise it would try to unmount subdir of the volume
+			return filepath.SkipDir
 		})
 		if err != nil {
 			return fmt.Errorf("error processing %s: %s", fullContainerDirPath, err)

pkg/volume/util/subpath/subpath_linux_test.go

@@ -409,6 +409,7 @@ func TestCleanSubPaths(t *testing.T) {
 		// Function that validates directory structure after the test
 		validate    func(base string) error
 		expectError bool
+		umount      func(path string) error
 	}{
 		{
 			name: "not-exists",
@@ -539,6 +540,37 @@ func TestCleanSubPaths(t *testing.T) {
 				return validateDirExists(baseSubdir)
 			},
 		},
+		{
+			name: "subpath-with-files",
+			prepare: func(base string) ([]mount.MountPoint, error) {
+				path := filepath.Join(base, containerSubPathDirectoryName, testVol, "container1", "0")
+				path2 := filepath.Join(base, containerSubPathDirectoryName, testVol, "container1", "1")
+				if err := os.MkdirAll(filepath.Join(path, "my-dir-1"), defaultPerm); err != nil {
+					return nil, err
+				}
+				if err := os.MkdirAll(filepath.Join(path2, "my-dir-2"), defaultPerm); err != nil {
+					return nil, err
+				}
+				mounts := []mount.MountPoint{
+					{Device: "/dev/sdb", Path: path},
+					{Device: "/dev/sdc", Path: path2},
+				}
+				return mounts, nil
+			},
+			umount: func(mountpath string) error {
+				fileInfo, err := ioutil.ReadDir(mountpath)
+				for _, file := range fileInfo {
+					if err = os.RemoveAll(filepath.Join(mountpath, file.Name())); err != nil {
+						return err
+					}
+				}
+
+				return nil
+			},
+			validate: func(base string) error {
+				return validateDirNotExists(filepath.Join(base, containerSubPathDirectoryName))
+			},
+		},
 	}
 
 	for _, test := range tests {
@@ -553,7 +585,7 @@ func TestCleanSubPaths(t *testing.T) {
 			t.Fatalf("failed to prepare test %q: %v", test.name, err.Error())
 		}
 
-		fm := &mount.FakeMounter{MountPoints: mounts}
+		fm := &mount.FakeMounter{MountPoints: mounts, UmountFunc: test.umount}
 
 		err = doCleanSubPaths(fm, base, testVol)
 		if err != nil && !test.expectError {