From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-4.0 required=3.0 tests=AWL,BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 989001F803 for ; Tue, 8 Jan 2019 06:35:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727654AbfAHGe7 (ORCPT ); Tue, 8 Jan 2019 01:34:59 -0500 Received: from cloud.peff.net ([104.130.231.41]:57378 "HELO cloud.peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1727538AbfAHGe7 (ORCPT ); Tue, 8 Jan 2019 01:34:59 -0500 Received: (qmail 1106 invoked by uid 109); 8 Jan 2019 06:35:00 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.94) with SMTP; Tue, 08 Jan 2019 06:35:00 +0000 Authentication-Results: cloud.peff.net; auth=none Received: (qmail 8569 invoked by uid 111); 8 Jan 2019 06:34:57 -0000 Received: from sigill.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.7) by peff.net (qpsmtpd/0.94) with (ECDHE-RSA-AES256-GCM-SHA384 encrypted) SMTP; Tue, 08 Jan 2019 01:34:57 -0500 Authentication-Results: peff.net; auth=none Received: by sigill.intra.peff.net (sSMTP sendmail emulation); Tue, 08 Jan 2019 01:34:56 -0500 Date: Tue, 8 Jan 2019 01:34:56 -0500 From: Jeff King To: Guilhem Bonnefille Cc: Git List Subject: Re: Suspicious fetch-pack behaviour Message-ID: <20190108063456.GA17588@sigill.intra.peff.net> References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Thu, Jan 03, 2019 at 10:52:48AM +0100, Guilhem Bonnefille wrote: > One of my users reported a strange problem: a simple HTTPS clone did > not work with Git 1.8.3.1 on RedHat 7. > I did many tests and I was not able to understand why his clone don't > work while I'm able to do it on other similar host. > > Nevertheless, we did more investigations. One of them: a raw strace. > I discovered two strange behaviours: > - fetch-pack closes its standard input and standard output and then > tries to print the references on standard input and finaly dies. > - git-remote-https does not react to fetch-pack death and continue > polling an empty set of FD. > > [...] > > 2769 poll(NULL, 0, 1000) = 0 (Timeout) We actually don't use poll() very much in Git. And poking around the v1.8.3.1 source, I do not see any places where remote-https would call poll(), and none outside of "git help" and "git credential-cache-daemon" that would ever provide a timeout like "1000". I wonder if this poll is actually being run by libcurl. Is it possible to get a backtrace of the looping process with gdb? I'd also point out that v1.8.3.1 is over 5 years old, and there have been quite a few http-related fixes over the years. There is a good chance that if this is a Git bug, it has long since been fixed. Is it possible to reproduce with a more modern version of Git? -Peff