diff --git a/util/migrate/backfill_v1_metadata.py b/util/migrate/backfill_v1_metadata.py
index e9de7e9a2..20680f077 100644
--- a/util/migrate/backfill_v1_metadata.py
+++ b/util/migrate/backfill_v1_metadata.py
@@ -56,7 +56,7 @@ class ImageStoragePlacement(BaseModel):
 
 
 def image_json_path(storage_uuid):
-  base_path = storage.image_path(storage_uuid)
+  base_path = storage._image_path(storage_uuid)
   return '{0}json'.format(base_path)