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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7C40DC433F5 for ; Mon, 25 Apr 2022 21:01:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245336AbiDYVEY (ORCPT ); Mon, 25 Apr 2022 17:04:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55010 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231753AbiDYVEY (ORCPT ); Mon, 25 Apr 2022 17:04:24 -0400 Received: from mail-wm1-x32e.google.com (mail-wm1-x32e.google.com [IPv6:2a00:1450:4864:20::32e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E4991167C4; Mon, 25 Apr 2022 14:01:18 -0700 (PDT) Received: by mail-wm1-x32e.google.com with SMTP id u17-20020a05600c211100b0038eaf4cdaaeso309877wml.1; Mon, 25 Apr 2022 14:01:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=F0Wqha00tJlONZuaPT+kIQeQKt6+cyUurVU3OwL9MQ8=; b=Cox9LyVwKYukwokad9zF3+dkLCkrBEMLcFoiTsgL3EcV2ue6iyY2KSSJl0MZMVTm5W iTf1akXBASsM/m1o4cDefkTymgrUsu4kg0bcB70ohCuQzxdP60/DWaoXmAz9paRizmV2 7fIyk097aNIAkatUVyhiaE6tJNANsM/fYYEHCAALSJBCgOrJXLifFGYj2uGlQWSbHxI7 fN1MypHnLdh7S9vAri+LfJ37kduF71FJ7FFjhto6pXt583zVY3ye+kpU1XsLFJUPmb8h A1fhiOnqY+2ZoLUGufeY4MYUOGljoTjRPPjeZHTEiFtq95812LpX7IMBFXiyZAVs0Acj L73w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=F0Wqha00tJlONZuaPT+kIQeQKt6+cyUurVU3OwL9MQ8=; b=4vR1hNA9gcUdO79EzMv6CpsIzZZ/7nCvcjHjzFbWyfCI2h35Tdte6XGrJ7ns7bgMdj t1BfBepsZoRkK7jRjY95H98FKkxcbqd7ff9/FySamW9znyhRVTUUqu+DN2eF4ebDXTRW A7cuoCmT0zuEa6ASl5eBBXvDnwNHaW0H8FYAzb+KXj1TZfCUO2TTVM8ItuICUWo81aSW vg0vrA+51gk9MbV0vNS3qE2xx5dG0yFv1gL/7uJNWPPGsVmRiDFd4XcWdODSiE8mZSM6 NMClyqyP2jcZCktx41hM2cLSDsBtDA8CZptGB7r0TTY71qIilYBsdROBDWMA56ZS8ua/ rNOg== X-Gm-Message-State: AOAM530WiPA9HSynneH0RxU/iFGXelAIi7BvpagpkWai9O4GNzVLDGF/ SKVPEvJcWbvbuP0KwmDQ3uQ= X-Google-Smtp-Source: ABdhPJyN+qjSO23iBiSRTCicfMm9+inXCycFjx6L88fyJtPxu99EfrcvJewaw6pSqSPd+yNZ9eANRg== X-Received: by 2002:a1c:ac44:0:b0:38e:a7df:3179 with SMTP id v65-20020a1cac44000000b0038ea7df3179mr18634853wme.61.1650920477587; Mon, 25 Apr 2022 14:01:17 -0700 (PDT) Received: from [192.168.0.160] ([170.253.36.171]) by smtp.gmail.com with ESMTPSA id b2-20020adfc742000000b0020ac89e4241sm10732022wrh.31.2022.04.25.14.01.16 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 25 Apr 2022 14:01:17 -0700 (PDT) Message-ID: <31702ffb-380f-69f9-ab87-3aec5b22537c@gmail.com> Date: Mon, 25 Apr 2022 23:01:15 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.8.0 Subject: Re: [PATCH] bpf.2: Note that unused fields and padding in bpf_attr must be zero Content-Language: en-US To: Jakub Sitnicki , linux-man@vger.kernel.org Cc: bpf@vger.kernel.org, Michael Kerrisk , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko References: <20220425160803.114851-1-jakub@cloudflare.com> From: Alejandro Colomar In-Reply-To: <20220425160803.114851-1-jakub@cloudflare.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Hi Jakub, On 4/25/22 18:08, Jakub Sitnicki wrote: > In a discussion regarding a potential backward incompatible change [1], > Andrii Nakryiko points out that unused bytes of bpf_attr should be > zero. Add this bit of information to the bpf(2) man page. > > [1] https://lore.kernel.org/bpf/CAEf4BzbT4vQBnZzdD00SuPCDkeb4Cm=F6PLUoO_3X93UQD5hbQ@mail.gmail.com/ > > Signed-off-by: Jakub Sitnicki Patch applied. Thanks, Alex > --- > man2/bpf.2 | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/man2/bpf.2 b/man2/bpf.2 > index 2d257eaa6..ee57226ee 100644 > --- a/man2/bpf.2 > +++ b/man2/bpf.2 > @@ -142,7 +142,7 @@ provided via > .IR attr , > which is a pointer to a union of type > .I bpf_attr > -(see below). > +(see below). The unused fields and padding must be zeroed out before the call. But I changed it to add a separate line, instead of continuation in the same one. > The > .I size > argument is the size of the union pointed to by