diff --git a/build_library/disk_util b/build_library/disk_util
index 49446106ed..3ab9d1ab87 100755
--- a/build_library/disk_util
+++ b/build_library/disk_util
@@ -65,7 +65,7 @@ def LoadPartitionConfig(options):
     metadata = config['metadata']
     base = config['layouts']['base']
     for key in ('part_alignment', 'disk_alignment',
-		'block_size', 'fs_block_size'):
+        'block_size', 'fs_block_size'):
       metadata[key] = int(metadata[key])
   except KeyError as e:
     raise InvalidLayout('Metadata is missing required entries: %s' % e)