diff --git a/src/proto_http.c b/src/proto_http.c
index 820f6434f..7e1d738d8 100644
--- a/src/proto_http.c
+++ b/src/proto_http.c
@@ -3540,7 +3540,7 @@ int http_process_tarpit(struct session *s, struct buffer *req, int an_bit)
 	s->logs.t_queue = tv_ms_elapsed(&s->logs.tv_accept, &now);
 
 	txn->status = 500;
-	if (req->flags != BF_READ_ERROR)
+	if (!(req->flags & BF_READ_ERROR))
 		stream_int_retnclose(req->prod, error_message(s, HTTP_ERR_500));
 
 	req->analysers = 0;