diff --git a/src/hb-open-file.hh b/src/hb-open-file.hh
index cd7d78a3e..a1f931d3c 100644
--- a/src/hb-open-file.hh
+++ b/src/hb-open-file.hh
@@ -432,6 +432,7 @@ struct ResourceForkHeader
   {
     TRACE_SANITIZE (this);
     return_trace (c->check_struct (this) &&
+		  data.sanitize (c, this, dataLen) &&
 		  map.sanitize (c, this, &(this+data)));
   }