From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AFBB0C5ACD6 for ; Tue, 17 Mar 2020 18:58:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 94FBC20724 for ; Tue, 17 Mar 2020 18:58:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726575AbgCQS6d (ORCPT ); Tue, 17 Mar 2020 14:58:33 -0400 Received: from www62.your-server.de ([213.133.104.62]:60058 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726491AbgCQS6c (ORCPT ); Tue, 17 Mar 2020 14:58:32 -0400 Received: from sslproxy05.your-server.de ([78.46.172.2]) by www62.your-server.de with esmtpsa (TLSv1.2:DHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89_1) (envelope-from ) id 1jEHQ6-000220-EW; Tue, 17 Mar 2020 19:58:30 +0100 Received: from [85.7.42.192] (helo=pc-9.home) by sslproxy05.your-server.de with esmtpsa (TLSv1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1jEHQ6-000IWf-6U; Tue, 17 Mar 2020 19:58:30 +0100 Subject: Re: [PATCH bpf-next 1/3] selftests/bpf: fix race in tcp_rtt test To: Andrii Nakryiko , bpf@vger.kernel.org, netdev@vger.kernel.org, ast@fb.com Cc: andrii.nakryiko@gmail.com, kernel-team@fb.com References: <20200314013932.4035712-1-andriin@fb.com> From: Daniel Borkmann Message-ID: <9d9ce812-123a-00d1-9985-8a38f3ae62b4@iogearbox.net> Date: Tue, 17 Mar 2020 19:58:29 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20200314013932.4035712-1-andriin@fb.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Authenticated-Sender: daniel@iogearbox.net X-Virus-Scanned: Clear (ClamAV 0.102.2/25754/Tue Mar 17 14:09:15 2020) Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On 3/14/20 2:39 AM, Andrii Nakryiko wrote: > Previous attempt to make tcp_rtt more robust introduced a new race, in which > server_done might be set to true before server can actually accept any > connection. Fix this by unconditionally waiting for accept(). Given socket is > non-blocking, if there are any problems with client side, it should eventually > close listening FD and let server thread exit with failure. > > Fixes: 4cd729fa022c ("selftests/bpf: Make tcp_rtt test more robust to failures") > Signed-off-by: Andrii Nakryiko Series applied, thanks!