diff --git a/include/hardware/keymaster_defs.h b/include/hardware/keymaster_defs.h
index e95850a..b45e785 100644
--- a/include/hardware/keymaster_defs.h
+++ b/include/hardware/keymaster_defs.h
@@ -587,6 +587,7 @@
         keymaster_free_param_values(set->params, set->length);
         free(set->params);
         set->params = NULL;
+        set->length = 0;
     }
 }