diff --git a/lib/http2.c b/lib/http2.c
index a6e2cc658..fc0d5de91 100644
--- a/lib/http2.c
+++ b/lib/http2.c
@@ -721,7 +721,7 @@ static int on_header(nghttp2_session *session, const nghttp2_frame *frame,
       if(!headp) {
         free(stream->push_headers);
         stream->push_headers = NULL;
-        return 1;
+        return NGHTTP2_ERR_TEMPORAL_CALLBACK_FAILURE;
       }
       stream->push_headers = headp;
     }