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=-4.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 4ABCEC47093 for ; Mon, 31 May 2021 01:31:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2306A611EE for ; Mon, 31 May 2021 01:31:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230006AbhEaBd2 (ORCPT ); Sun, 30 May 2021 21:33:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40464 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229891AbhEaBd0 (ORCPT ); Sun, 30 May 2021 21:33:26 -0400 Received: from mail-ot1-x32e.google.com (mail-ot1-x32e.google.com [IPv6:2607:f8b0:4864:20::32e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6B19AC061574 for ; Sun, 30 May 2021 18:31:45 -0700 (PDT) Received: by mail-ot1-x32e.google.com with SMTP id i23-20020a9d68d70000b02902dc19ed4c15so9693104oto.0 for ; Sun, 30 May 2021 18:31:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=A/Dn9ugc/xkidX4z9k+NtNePIBtXCwu2DLEwl+0IIls=; b=glLYgJzfXA5ySiTt89c2CJaKMlM52VeHdkDIEzz8/DADH0SBqRdj5qBQ5er+XNWsCR /aVNiL/QDhjCfnTz3VqJWx/Sjras89sFFypvkpbYAnfscsk1Zuuii+/s5DtATnuAleTb wqsOnFxJBnx9gp8K4Vrhz36XbQEUMu5FTyXGiRRzbXiW49r1SAa+k0PlRr1w3dHc07Ts 56lIyM7nO0lMgluQ/veaD0pt4DzYtxkZ25yCTt2yqkJP+EVZYFWxmXo1QxKhC+7bi37W JNgt9ehwNThKeH2n7MEu7qyw+aOyRZtPxJaADxvCIBYHFPi+NspCITlfO8Oj6TVhkcXi WfhQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=A/Dn9ugc/xkidX4z9k+NtNePIBtXCwu2DLEwl+0IIls=; b=M1W4m11CsTvPVPLum/HljNXV+istp5QzVdsStZWcSR16/LMf9Boiweq6aY2YzzmiNT +4dyhuR+0U2aovsat4cIZosf9xN7Vb+PVxunzwcLVPxdu1VJpGvYwpPo434Y45IvmfE5 ra5S0S8kkBpK0zNW7iwbuWXe9p+0Rsfd6CQ5UaH4yukvtj2Ibd+3GczulklfnB8WMKQB vF09np6CLYZ51acbSAT150zPElYtfHkajlIYhavrszCra5UJv82DqFSOcl21dn4aNGbD +YRNsq21UVIMqYYKGS8YoVPwjIDkk0jjjW3xTLQcegVxgK+QzihrVzhoUj8Pt9PoqoRn UVVA== X-Gm-Message-State: AOAM533wlOI71lO7yf0PFO8lmBvW68jSjniyVKqsXn25WN7EN28Wnw4F 0tBfsxQCpU6xRN5TkwyFL5Q= X-Google-Smtp-Source: ABdhPJx7LiuiqUAzXaIwQ4nb/Xht6YFtrvOyLVGfSTsif6DL6w8/D/TaTkKPPn86/reNf/vTNes9ug== X-Received: by 2002:a9d:1791:: with SMTP id j17mr5970913otj.366.1622424704843; Sun, 30 May 2021 18:31:44 -0700 (PDT) Received: from Davids-MacBook-Pro.local ([8.48.134.22]) by smtp.googlemail.com with ESMTPSA id 12sm479133ooy.0.2021.05.30.18.31.43 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 30 May 2021 18:31:44 -0700 (PDT) Subject: Re: [PATCH net] udp: fix the len check in udp_lib_getsockopt To: Xin Long Cc: Jakub Kicinski , network dev , davem , Eric Dumazet , Paolo Abeni References: <04cb0c7f6884224c99fbf656579250896af82d5b.1622142759.git.lucien.xin@gmail.com> <20210528153911.4f67a691@kicinski-fedora-PC1C0HJN.hsd1.ca.comcast.net> <54cb4e46-28f9-b6db-85ec-f67df1e6bacf@gmail.com> From: David Ahern Message-ID: Date: Sun, 30 May 2021 19:31:43 -0600 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.10.2 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 5/29/21 10:47 AM, Xin Long wrote: > On Fri, May 28, 2021 at 9:57 PM David Ahern wrote: >> >> On 5/28/21 7:47 PM, Xin Long wrote: >>> The partial byte(or even 0) of the value returned due to passing a wrong >>> optlen should be considered as an error. "On error, -1 is returned, and >>> errno is set appropriately.". Success returned in that case only confuses >>> the user. >> >> It is feasible that some app could use bool or u8 for options that have >> 0 or 1 values and that code has so far worked. This change would break that. > Got it. > Not sure if it's possible or necessary to also return -EINVAL if optlen == 0 > do_tcp_getsockopt for example does not fail on optlen 0; no reason to make this one fail.