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=-4.2 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,URIBL_BLOCKED,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 9F0CDC64E7A for ; Tue, 1 Dec 2020 21:36:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2A5982085B for ; Tue, 1 Dec 2020 21:36:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="oDLZiMXN" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728023AbgLAVgT (ORCPT ); Tue, 1 Dec 2020 16:36:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55990 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727686AbgLAVgT (ORCPT ); Tue, 1 Dec 2020 16:36:19 -0500 Received: from mail-wr1-x444.google.com (mail-wr1-x444.google.com [IPv6:2a00:1450:4864:20::444]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B189EC0613CF; Tue, 1 Dec 2020 13:35:38 -0800 (PST) Received: by mail-wr1-x444.google.com with SMTP id g14so5081377wrm.13; Tue, 01 Dec 2020 13:35:38 -0800 (PST) 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=MennaIdlw2rEfhCE57v1/ns19QjTPenrLTqIfgoLes4=; b=oDLZiMXNP1Qpp/9lQP8OXFoKc5aMJnzV3TCR5AMdYEQNy10OOR6q4SFp/Z/np5DNPz fC9MUO8KQm1bK0OA86alShZykConycG+bOdcfix9ealb6IZ5ImvuE/bMxKom6fIrat/Q QG5hGize0Pd303ToGTILDNGVdhauUtlFJAGZKY+zZbZk8WHx+jfLUFBU5k+UPWzKYY7A p/L2yBK3bxAI1VstY2+uoqxj0PmV4YnVcPgLwYWATu2Fj8YRJfmzlu+Dj1zS+b2/lMIK vNOj3b5ueYTldjX78BENmO4/E5utXFspw61jc8QnRhg9ZkEafma+/rYZ/XdzuUYiUKog 568A== 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=MennaIdlw2rEfhCE57v1/ns19QjTPenrLTqIfgoLes4=; b=ZvQDZS9/BDjj8DbYHEu4KiATsLTvgGREIeIrFkn+CNm86e+fSxEdG75WcKgpE2H+xz hiY90pOXbedwnI9QI5DU/NpLC7Newgg6CL/LY2T4Nbmyxo3Y+DmcCFdpd4Nd6PcrU3w8 b2EBCssp0m9c3CwNdhbxebZp4kEb5pK3vagdvPqTEhf9jcnn/7yCnG9YMdXRIAnOt6e8 MOdRx5eYDX9Xjyuysry4PSxqesBX0dPUE+QEBe3y/J4rRbhOAajNr4rF5hK+K5URFhGO tHghM6P4Lk9fCFuzQIjqTPk1JQQ7fK445ZRK/j+yfKbH/lgiMxY3395Y3YncdO2QvSr5 DnZg== X-Gm-Message-State: AOAM532UwvenC0XKRYN9UOqlM7KJ/EUX5M6PhQG+pTkPqd3KddjTII7l MEbvP8+lLU/lNO3fyny2RHuQzfPr+9nWSQ== X-Google-Smtp-Source: ABdhPJypKIOGoGzHXfvUCF1MBGOs/Z8aeKjMSOFB6aLlqfr3TdAVnqM+BkpSQGwadQ5RgM7SF1M5dA== X-Received: by 2002:a5d:5741:: with SMTP id q1mr6519927wrw.160.1606858537307; Tue, 01 Dec 2020 13:35:37 -0800 (PST) Received: from [192.168.1.143] ([170.253.51.130]) by smtp.gmail.com with ESMTPSA id v3sm1348933wrq.72.2020.12.01.13.35.36 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 01 Dec 2020 13:35:36 -0800 (PST) Subject: Re: [PATCH man-pages v6] Document encoded I/O To: "Michael Kerrisk (man-pages)" , Omar Sandoval Cc: linux-fsdevel@vger.kernel.org, linux-btrfs@vger.kernel.org, Al Viro , Christoph Hellwig , Dave Chinner , Jann Horn , Amir Goldstein , Aleksa Sarai , linux-api@vger.kernel.org, kernel-team@fb.com, linux-man References: <4d1430aa-a374-7565-4009-7ec5139bf311@gmail.com> <05e1f13c-5776-961b-edc4-0d09d02b7829@gmail.com> <559edb86-4223-71e9-9ebf-c917ae71a13d@gmail.com> From: "Alejandro Colomar (man-pages)" Message-ID: <2aca4914-d247-28d1-22e0-102ea5ff826e@gmail.com> Date: Tue, 1 Dec 2020 22:35:35 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: <559edb86-4223-71e9-9ebf-c917ae71a13d@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-man@vger.kernel.org Hi Michael, On 12/1/20 9:20 PM, Michael Kerrisk (man-pages) wrote: >>>>>> +.SS Security >>>>>> +Encoded I/O creates the potential for some security issues: >>>>>> +.IP * 3 >>>>>> +Encoded writes allow writing arbitrary data which the kernel will decode on >>>>>> +a subsequent read. Decompression algorithms are complex and may have bugs >>>>>> +which can be exploited by maliciously crafted data. >>>>>> +.IP * >>>>>> +Encoded reads may return data which is not logically present in the file >>>>>> +(see the discussion of >>>>>> +.I len >>>>>> +vs. >>>>> >>>>> Please, s/vs./vs/ >>>>> See the reasons below: >>>>> >>>>> Michael (mtk), >>>>> >>>>> Here the renderer outputs a double space >>>>> (as for separating two sentences). >>>>> >>>>> Are you okay with that? >> >> Yes, that should probably be avoided. I'm not sure what the >> correct way is to prevent that in groff though. I mean, one >> could write >> >> .RI "vs.\ " unencoded_len >> >> but I think that simply creates a nonbreaking space, >> which is not exactly what is desired. > > Ahh -- found it. From https://groff.ffii.org/groff/groff-1.21.pdf, > we can write: > > vs.\& > > to prevent the double space. Nice to see it's possible. However, I would argue for simplicity, and use a simple 'vs', which is already in use. Cheers, Alex > > Thanks, > > Michael > >