fix 9234: Add safe VolumeSnapshotterCache

Signed-off-by: 0xLeo258 <noixe0312@gmail.com>

pkg/backup/backup.go

@@ -366,7 +366,7 @@ func (kb *kubernetesBackupper) BackupWithResolvers(
 		discoveryHelper:          kb.discoveryHelper,
 		podVolumeBackupper:       podVolumeBackupper,
 		podVolumeSnapshotTracker: podvolume.NewTracker(),
-		volumeSnapshotterGetter:  volumeSnapshotterGetter,
+		volumeSnapshotterCache:   NewVolumeSnapshotterCache(volumeSnapshotterGetter),
 		itemHookHandler: &hook.DefaultItemHookHandler{
 			PodCommandExecutor: kb.podCommandExecutor,
 		},

pkg/backup/item_backupper.go

@@ -70,13 +70,11 @@ type itemBackupper struct {
 	discoveryHelper          discovery.Helper
 	podVolumeBackupper       podvolume.Backupper
 	podVolumeSnapshotTracker *podvolume.Tracker
-	volumeSnapshotterGetter  VolumeSnapshotterGetter
 	kubernetesBackupper      *kubernetesBackupper
-
-	itemHookHandler                    hook.ItemHookHandler
-	snapshotLocationVolumeSnapshotters map[string]vsv1.VolumeSnapshotter
-	hookTracker                        *hook.HookTracker
-	volumeHelperImpl                   volumehelper.VolumeHelper
+	volumeSnapshotterCache   *VolumeSnapshotterCache
+	itemHookHandler          hook.ItemHookHandler
+	hookTracker              *hook.HookTracker
+	volumeHelperImpl         volumehelper.VolumeHelper
 }
 
 type FileForArchive struct {
@@ -502,30 +500,6 @@ func (ib *itemBackupper) executeActions(
 	return obj, itemFiles, nil
 }
 
-// volumeSnapshotter instantiates and initializes a VolumeSnapshotter given a VolumeSnapshotLocation,
-// or returns an existing one if one's already been initialized for the location.
-func (ib *itemBackupper) volumeSnapshotter(snapshotLocation *velerov1api.VolumeSnapshotLocation) (vsv1.VolumeSnapshotter, error) {
-	if bs, ok := ib.snapshotLocationVolumeSnapshotters[snapshotLocation.Name]; ok {
-		return bs, nil
-	}
-
-	bs, err := ib.volumeSnapshotterGetter.GetVolumeSnapshotter(snapshotLocation.Spec.Provider)
-	if err != nil {
-		return nil, err
-	}
-
-	if err := bs.Init(snapshotLocation.Spec.Config); err != nil {
-		return nil, err
-	}
-
-	if ib.snapshotLocationVolumeSnapshotters == nil {
-		ib.snapshotLocationVolumeSnapshotters = make(map[string]vsv1.VolumeSnapshotter)
-	}
-	ib.snapshotLocationVolumeSnapshotters[snapshotLocation.Name] = bs
-
-	return bs, nil
-}
-
 // zoneLabelDeprecated is the label that stores availability-zone info
 // on PVs this is deprecated on Kubernetes >= 1.17.0
 // zoneLabel is the label that stores availability-zone info
@@ -641,7 +615,7 @@ func (ib *itemBackupper) takePVSnapshot(obj runtime.Unstructured, log logrus.Fie
 	for _, snapshotLocation := range ib.backupRequest.SnapshotLocations {
 		log := log.WithField("volumeSnapshotLocation", snapshotLocation.Name)
 
-		bs, err := ib.volumeSnapshotter(snapshotLocation)
+		bs, err := ib.volumeSnapshotterCache.SetNX(snapshotLocation)
 		if err != nil {
 			log.WithError(err).Error("Error getting volume snapshotter for volume snapshot location")
 			continue

pkg/backup/volume_snapshotter_cache.go

@@ -0,0 +1,42 @@
+package backup
+
+import (
+	"sync"
+
+	velerov1api "github.com/vmware-tanzu/velero/pkg/apis/velero/v1"
+	vsv1 "github.com/vmware-tanzu/velero/pkg/plugin/velero/volumesnapshotter/v1"
+)
+
+type VolumeSnapshotterCache struct {
+	cache  map[string]vsv1.VolumeSnapshotter
+	mutex  sync.Mutex
+	getter VolumeSnapshotterGetter
+}
+
+func NewVolumeSnapshotterCache(getter VolumeSnapshotterGetter) *VolumeSnapshotterCache {
+	return &VolumeSnapshotterCache{
+		cache:  make(map[string]vsv1.VolumeSnapshotter),
+		getter: getter,
+	}
+}
+
+func (c *VolumeSnapshotterCache) SetNX(location *velerov1api.VolumeSnapshotLocation) (vsv1.VolumeSnapshotter, error) {
+	c.mutex.Lock()
+	defer c.mutex.Unlock()
+
+	if snapshotter, exists := c.cache[location.Name]; exists {
+		return snapshotter, nil
+	}
+
+	snapshotter, err := c.getter.GetVolumeSnapshotter(location.Spec.Provider)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := snapshotter.Init(location.Spec.Config); err != nil {
+		return nil, err
+	}
+
+	c.cache[location.Name] = snapshotter
+	return snapshotter, nil
+}