diff --git a/tools/releasetools/fsverity_metadata_generator.py b/tools/releasetools/fsverity_metadata_generator.py
index a300d2e932..fa7cd3934a 100644
--- a/tools/releasetools/fsverity_metadata_generator.py
+++ b/tools/releasetools/fsverity_metadata_generator.py
@@ -178,6 +178,7 @@ class FSVerityMetadataGenerator:
           out.write(sig)
       else:
         out.write(pack('<I', SIG_TYPE_NONE))
+        out.write(pack('<I', 0))
 
       # 4. merkle tree
       with open(merkletree_file, 'rb') as f: