diff --git a/lib/nghttp2_session.c b/lib/nghttp2_session.c
index 6f3843c8..fffdf45d 100644
--- a/lib/nghttp2_session.c
+++ b/lib/nghttp2_session.c
@@ -231,6 +231,8 @@ static void session_inbound_frame_reset(nghttp2_session *session) {
      nghttp2_session_new(), we rely on the fact that
      iframe->frame.hd.type is 0, so that no free is performed. */
   switch (iframe->frame.hd.type) {
+  case NGHTTP2_DATA:
+    break;
   case NGHTTP2_HEADERS:
     nghttp2_frame_headers_free(&iframe->frame.headers, mem);
     break;
@@ -255,6 +257,10 @@ static void session_inbound_frame_reset(nghttp2_session *session) {
   case NGHTTP2_WINDOW_UPDATE:
     nghttp2_frame_window_update_free(&iframe->frame.window_update);
     break;
+  default:
+    /* extension frame */
+    nghttp2_frame_extension_free(&iframe->frame.ext);
+    break;
   }
 
   memset(&iframe->frame, 0, sizeof(nghttp2_frame));