fix: use safe type assertion and fix path construction in createFolderIfNotExists

pkg/azurefile/azurefile.go

@@ -1471,12 +1471,26 @@ func isKataNode(ctx context.Context, nodeID, confidentialContainerLabel string,
 // createFolderIfNotExists creates a folder in Azure File Share if it doesn't already exist
 // This function handles nested paths by creating each directory level recursively
 func (d *Driver) createFolderIfNotExists(ctx context.Context, accountName, accountKey, fileShareName, folderName, storageEndpointSuffix string) error {
+	if accountName == "" {
+		return fmt.Errorf("accountName is empty")
+	}
+	if fileShareName == "" {
+		return fmt.Errorf("fileShareName is empty")
+	}
+
 	fileClient, err := newAzureFileClient(accountName, accountKey, storageEndpointSuffix)
-	if err != nil || fileClient.(*azureFileDataplaneClient).Client == nil {
-		return fmt.Errorf("create Azure File client(%s) failed: %v", accountName, err)
+	if err != nil {
+		return fmt.Errorf("create Azure File client(%s) failed: %w", accountName, err)
+	}
+	dc, ok := fileClient.(*azureFileDataplaneClient)
+	if !ok {
+		return fmt.Errorf("create Azure File client(%s) failed: expected *azureFileDataplaneClient but got %T", accountName, fileClient)
+	}
+	if dc.Client == nil {
+		return fmt.Errorf("create Azure File client(%s) failed: dataplane client is nil", accountName)
 	}
 
-	shareClient := fileClient.(*azureFileDataplaneClient).Client.NewShareClient(fileShareName)
+	shareClient := dc.Client.NewShareClient(fileShareName)
 
 	// Performance optimization: First check if the complete directory structure already exists
 	// This is the most common case and avoids unnecessary recursive checking
@@ -1501,12 +1515,12 @@ func (d *Driver) createFolderIfNotExists(ctx context.Context, accountName, accou
 
 	// Build path incrementally and create each directory level
 	currentPath := ""
-	for i, component := range pathComponents {
+	for _, component := range pathComponents {
 		if component == "" {
 			continue // Skip empty components
 		}
 
-		if i > 0 {
+		if currentPath != "" {
 			currentPath += "/"
 		}
 		currentPath += component

pkg/azurefile/azurefile_test.go

@@ -1942,6 +1942,24 @@ func TestCreateFolderIfNotExists(t *testing.T) {
 		storageEndpointSuffix string
 		expectedError         string
 	}{
+		{
+			name:                  "Empty account name",
+			accountName:           "",
+			accountKey:            base64.StdEncoding.EncodeToString([]byte("testkey")),
+			fileShareName:         "testshare",
+			folderName:            "testfolder",
+			storageEndpointSuffix: "core.windows.net",
+			expectedError:         "accountName is empty",
+		},
+		{
+			name:                  "Empty file share name",
+			accountName:           "testaccount",
+			accountKey:            base64.StdEncoding.EncodeToString([]byte("testkey")),
+			fileShareName:         "",
+			folderName:            "testfolder",
+			storageEndpointSuffix: "core.windows.net",
+			expectedError:         "fileShareName is empty",
+		},
 		{
 			name:                  "Invalid account key",
 			accountName:           "testaccount",