diff --git a/tools/releasetools/build_image.py b/tools/releasetools/build_image.py
index 301d0da..2492da9 100755
--- a/tools/releasetools/build_image.py
+++ b/tools/releasetools/build_image.py
@@ -386,13 +386,14 @@
             in_dir, du_str,
             int(prop_dict.get("partition_reserved_size", 0)),
             int(prop_dict.get("partition_reserved_size", 0)) // BYTES_IN_MB))
-    print(
-        "The max image size for filesystem files is {} bytes ({} MB), out of a "
-        "total partition size of {} bytes ({} MB).".format(
-            int(prop_dict["image_size"]),
-            int(prop_dict["image_size"]) // BYTES_IN_MB,
-            int(prop_dict["partition_size"]),
-            int(prop_dict["partition_size"]) // BYTES_IN_MB))
+    if ("image_size" in prop_dict and "partition_size" in prop_dict):
+      print(
+          "The max image size for filesystem files is {} bytes ({} MB), "
+          "out of a total partition size of {} bytes ({} MB).".format(
+              int(prop_dict["image_size"]),
+              int(prop_dict["image_size"]) // BYTES_IN_MB,
+              int(prop_dict["partition_size"]),
+              int(prop_dict["partition_size"]) // BYTES_IN_MB))
     raise
 
   if run_e2fsck and prop_dict.get("skip_fsck") != "true":