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 C1F94C64E7A for ; Tue, 1 Dec 2020 20:21:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4FC732151B for ; Tue, 1 Dec 2020 20:21:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="nA1Jz7HZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392330AbgLAUUz (ORCPT ); Tue, 1 Dec 2020 15:20:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44282 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390839AbgLAUUz (ORCPT ); Tue, 1 Dec 2020 15:20:55 -0500 Received: from mail-ej1-x643.google.com (mail-ej1-x643.google.com [IPv6:2a00:1450:4864:20::643]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 67104C0613CF; Tue, 1 Dec 2020 12:20:14 -0800 (PST) Received: by mail-ej1-x643.google.com with SMTP id bo9so6886137ejb.13; Tue, 01 Dec 2020 12:20:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=cc:subject:to:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=x8LOvIW9VGbu6yVQC0pyKrIyyIVofSPETZZoCASouyA=; b=nA1Jz7HZaeXfSEKiNPJl/q7u9GSnhYFlckUd4kro9jPGdVi0T8Em3lTAoIT1xvRgSB 7rL2vrF2S25FyAHKz0G1FXswTlv/ts7BhgGmIp2b7QUaH1DYqohXDxf2kGAYWe3tB3Pv +mghG8BXdVUAAyr4cZ7WiTCv1L5V73RKBVb+bALOHd2mDPZs0x/Samby5ciP/SAD3YTD u1hwmNmrhkPkfgCUhqd7QtvB6Av0TyK+KIOVQgnTXgXaMQZMbr1B9Nn+DQoQczMboPI7 TvVaaujMkvmU2RFADjNYfXWXkyVvw9R2bIRn2w2HemlJyDKfkCbrgUjjmrOt9EZw+Ekh HjAQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:cc:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=x8LOvIW9VGbu6yVQC0pyKrIyyIVofSPETZZoCASouyA=; b=hF6S3oS6sJYWqqa4Jv2UeylExCsWmG/8sCMGF/nvvYzT1fzA+0L0dV6MJeWebkj9za ANZsqc3y0gQm9iUg0wTrp2YdQd5oNz4SANB9tVBpukabvbNpvVSkHz2+JHlGSuelJ9hZ tj4oWGZfZeV/47bZ7ahaGr9WGWWa7bJFNKlQ+oh7rLMMOb3Cr2f65Q3C1g+VV3eeKPM/ cxIB0FOdrwXr5T78/LhemJ+z5jIsEXJLxxJe8FdcFWuF8wqzx8ZmAINgJrHrbgE/ww/J 8mUDI6jZGo1JhrXbJRMoruteH5oztiDQgSAK7AsNLOtzumnBjLm0V2s5jwT2rUcBWzYf T/qA== X-Gm-Message-State: AOAM5306rzW8ebrbk1U1f9zf21320sw2LX3sep5WTqvg6x7wXsDNljI9 NVrvdch/hcIzzxwKFNJXwt/8ZOACs7WQ+A== X-Google-Smtp-Source: ABdhPJyVEOSJCwPaRQEfj3znNBo7PAU3VOgN6sVUI122w7l2cuG77aZZvke/Tq680gXd7mM2umrqNw== X-Received: by 2002:a17:907:2131:: with SMTP id qo17mr1104442ejb.546.1606854012831; Tue, 01 Dec 2020 12:20:12 -0800 (PST) Received: from ?IPv6:2001:a61:3aad:c501:15d9:d9fb:bc21:cb92? ([2001:a61:3aad:c501:15d9:d9fb:bc21:cb92]) by smtp.gmail.com with ESMTPSA id r7sm417224edv.39.2020.12.01.12.20.11 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 01 Dec 2020 12:20:12 -0800 (PST) Cc: mtk.manpages@gmail.com, 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 Subject: Re: [PATCH man-pages v6] Document encoded I/O To: "Alejandro Colomar (man-pages)" , Omar Sandoval References: <4d1430aa-a374-7565-4009-7ec5139bf311@gmail.com> <05e1f13c-5776-961b-edc4-0d09d02b7829@gmail.com> From: "Michael Kerrisk (man-pages)" Message-ID: <559edb86-4223-71e9-9ebf-c917ae71a13d@gmail.com> Date: Tue, 1 Dec 2020 21:20:10 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.4.0 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: linux-man@vger.kernel.org >>>>> +.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. Thanks, Michael -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/