From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=5.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,MAILING_LIST_MULTI,RCVD_IN_MSPIKE_H2 autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 17100 invoked from network); 10 Feb 2023 22:36:04 -0000 Received: from second.openwall.net (193.110.157.125) by inbox.vuxu.org with ESMTPUTF8; 10 Feb 2023 22:36:04 -0000 Received: (qmail 30163 invoked by uid 550); 10 Feb 2023 22:36:01 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Reply-To: musl@lists.openwall.com Received: (qmail 30125 invoked from network); 10 Feb 2023 22:36:00 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=e3xGKko+84JR1qxYMLQQtohBx05PY9avq9xFRKYJV9E=; b=LQbAOEv0K+WfX48F+Uv2hjvs7jVuk6CKRZX2Ws2NcISTkyn0iBm/re97z3W++cIESk ZyauWbkknaQ7DvxIvqOIqQshzsDHMvIcYKKP7JmCWY9vhol8m316+dZEHEq5TcJf5Bl8 ve85XZ//gG2Y5omfWBCaQmB2GyhBOfyhbCG1ubceb4Jk5AXL41Ue2ISbSGP5JPkCk6fZ hW4bTowSa+bCtGdBZN0D+FaWx1e9oyJlOv51o8uKL16LgRv0Hgr+jDTyqKFBhd2zga5e J8EnGQ7xxNm9GZLznvirHcHor93LEAwUQCW1ZU9Ekddo/dEKjnXtG5tpY3JeEpo0UdDP jPMw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=e3xGKko+84JR1qxYMLQQtohBx05PY9avq9xFRKYJV9E=; b=BJo0gVLmultPBgXGUz00V8n1PcA3wq1t87zX98hzhcBHKkZ0Pi3eGllTOVe8KxBER6 D2l4CoL+fravRo7HuGvhpNZW0DoBJeKHZEL5BM1R9EsBLasvEUgZQO6xUcpaS+Qf5SaJ X4WwJBkQEw0zDsnN2lM4y9+gErhRolE64vByxwldxXUAyifYagvMpWmRAlQ2GMp65jwr CcyciLeIIldcjfpKYPypnracthZWXFnvVdwVrqo6gbCiR8479vNcRm73uwrkVlMHpFHl 5GMAn65FLjPUUOtHKEO2NwCwCu38trf0tu4RYxVkWQxG+QJqN5Q2VhfhGoUzOHBN3bh6 raWA== X-Gm-Message-State: AO0yUKV2RO3c0EgQ2sTCh+71EQ5fMXoERi28npV7VrrkOxVjtuegYsOq BZG/MdQfCgDTL2smBBhbJiNs12VYf1O3Fw1yizLAkt6vAYCpGMD1 X-Google-Smtp-Source: AK7set/S339jgDzlg2BHTw9KiUBNhCJp9XSLBuQlwIG1Ue+zuA2RHAxThRk3lMxC166Spx1WYXmsMLZS20yIY7f9/G0= X-Received: by 2002:a5d:5612:0:b0:2c5:4c70:fc05 with SMTP id l18-20020a5d5612000000b002c54c70fc05mr83202wrv.632.1676068548444; Fri, 10 Feb 2023 14:35:48 -0800 (PST) MIME-Version: 1.0 References: <20230210002601.GY4163@brightrain.aerifal.cx> In-Reply-To: <20230210002601.GY4163@brightrain.aerifal.cx> From: Colin Cross Date: Fri, 10 Feb 2023 14:35:36 -0800 Message-ID: To: Rich Felker Cc: musl@lists.openwall.com Content-Type: multipart/mixed; boundary="000000000000737a6f05f4601ef7" Subject: Re: [musl] Increase sendmsg internal buffer to match kernel SCM_MAX_FD limit --000000000000737a6f05f4601ef7 Content-Type: text/plain; charset="UTF-8" On Thu, Feb 9, 2023 at 4:26 PM Rich Felker wrote: > The concept of this seems fine, but if the limit was previously 255 on > supported kernel versions, why stop at 253? It doesn't really cost > anything to go up large enough that the 255 would work too. I can use 255. > As a technical detail, I'd probably also just put the full size > expression in the [], then use sizeof when you need it later. As > written, this change makes chbuf[] formally a VLA. The compiler > probably optimizes it to the same code as if it wasn't a VLA, but > there's no good reason for it to be a VLA. Using sizeof with the original buffer would have effectively fixed this issue, the extra "+1" in the number of chbuf elements adds 16 extra bytes to the buffer on x86_64, which would have been sufficient to hold the extra fds. It might as well be explicit though so it doesn't get reduced in the future. 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