diff --git a/migration/qjson.c b/migration/qjson.c
index 5cae55af07..f345904919 100644
--- a/migration/qjson.c
+++ b/migration/qjson.c
@@ -109,5 +109,6 @@ void qjson_finish(QJSON *json)
 
 void qjson_destroy(QJSON *json)
 {
+    QDECREF(json->str);
     g_free(json);
 }