diff --git a/core/java/android/service/gatekeeper/GateKeeperResponse.java b/core/java/android/service/gatekeeper/GateKeeperResponse.java
index 287dc76..9b52934 100644
--- a/core/java/android/service/gatekeeper/GateKeeperResponse.java
+++ b/core/java/android/service/gatekeeper/GateKeeperResponse.java
@@ -106,6 +106,8 @@
             if (mPayload != null) {
                 dest.writeInt(mPayload.length);
                 dest.writeByteArray(mPayload);
+            } else {
+                dest.writeInt(0);
             }
         }
     }