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=-2.8 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,SPF_HELO_NONE,SPF_PASS 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 DC90EC433DB for ; Tue, 19 Jan 2021 00:53:07 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6822223100 for ; Tue, 19 Jan 2021 00:53:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6822223100 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 7E04E8D002B; Mon, 18 Jan 2021 19:53:06 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 7904B8D0017; Mon, 18 Jan 2021 19:53:06 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6A6518D002B; Mon, 18 Jan 2021 19:53:06 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0030.hostedemail.com [216.40.44.30]) by kanga.kvack.org (Postfix) with ESMTP id 5514A8D0017 for ; Mon, 18 Jan 2021 19:53:06 -0500 (EST) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 12A88180ACEEE for ; Tue, 19 Jan 2021 00:53:06 +0000 (UTC) X-FDA: 77720700372.03.lamp17_2b05d0b2754d Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin03.hostedemail.com (Postfix) with ESMTP id A14A528A4EA for ; Tue, 19 Jan 2021 00:53:05 +0000 (UTC) X-HE-Tag: lamp17_2b05d0b2754d X-Filterd-Recvd-Size: 4431 Received: from mail-pl1-f175.google.com (mail-pl1-f175.google.com [209.85.214.175]) by imf34.hostedemail.com (Postfix) with ESMTP for ; Tue, 19 Jan 2021 00:53:05 +0000 (UTC) Received: by mail-pl1-f175.google.com with SMTP id s15so9544208plr.9 for ; Mon, 18 Jan 2021 16:53:05 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=mg+Koq9lZ29m0hUxgegkWW5EEE3qCkZDZp3mxHRiqw0=; b=LGG5Y1FHLZfLmnClZaLVaul72leJkAYHoBOlxgNpn7H3uAO0oF8h10RjG7NrnnN8t1 pjZHdijsDqNPhqMRULxkDdJBxatfrN87RkSQEG91pXHowqeIaAmBB833VpH+ykd5Pz+Y 9xLktuphI65BgGymIt8YOIV+3hzkYkEheRmpvSAc+UN/z9/i3upgD+bQbhLvDP/v+xs1 3g0DFS3lkDwLecyp2T8OaVp4w/QHK37lxxK7gl0/xnLJWLmQJbw/VDvaeyQpsMFUj0Oe aXaSb+sT7V1sMyF7JjucUGJYNuh89syuMnHR/Rl1xcl9jOxb/T5XXYAf5XqRY6fjVT9K Iniw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=mg+Koq9lZ29m0hUxgegkWW5EEE3qCkZDZp3mxHRiqw0=; b=MYE+xsvx4zY9Dt8V28dUUV2LLmcAmmPWNSv4n4OcuP6SjBHClKYHVMpzrckFiNvILe EOSCpFUFwn/pdFzRWcDrsBXQMKhRGZ1fj3U7qgdF4XPeQYtupocTcqWhjx3815Al4CeK J4spldo0KxD0u0JW49YMfycAxhDyaMcR8FEFBCuXMKCAngMk35znYJzdmHUfOC8+NJEp 61an2ZroweFqIJ2QODh9nr4ws/ET8MShJCvGd2lK1PreIjmoHCAGMj/CozxxA4kJ50Hs ssQ3D5xsZIGoAMBqz4CpUWCBBEp3+I/h4k8T1hFClhoPbs/c+7TAKR/gB/6i1V/QLgUW o8WQ== X-Gm-Message-State: AOAM532C9B6nJ1/t9FmwaZdE2mNnImxIES9MMX78Fmuy23YKj4m/m8wX FUYmw5ej+8sHeLzjPEas6lI= X-Google-Smtp-Source: ABdhPJy7q4KjN8lStiQNvymQ1gOiAbwpDRLg+pJL7opQQfA9UtzVt/R+aVmwwH8fDEqMpBNIezGMxg== X-Received: by 2002:a17:90a:d990:: with SMTP id d16mr2183806pjv.16.1611017584227; Mon, 18 Jan 2021 16:53:04 -0800 (PST) Received: from localhost ([2409:10:2e40:5100:6e29:95ff:fe2d:8f34]) by smtp.gmail.com with ESMTPSA id 5sm551318pjz.23.2021.01.18.16.53.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 18 Jan 2021 16:53:03 -0800 (PST) Date: Tue, 19 Jan 2021 09:53:01 +0900 From: Sergey Senozhatsky To: Timur Tabi Cc: Matthew Wilcox , Andrew Morton , linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, Sergey Senozhatsky , Petr Mladek , roman.fietze@magna.com, keescook@chromium.org, Steven Rostedt , John Ogness , linux-mm@kvack.org, Akinobu Mita Subject: Re: [PATCH 0/2] introduce DUMP_PREFIX_UNHASHED for hex dumps Message-ID: References: <20210116220950.47078-1-timur@kernel.org> <20210118182635.GD2260413@casper.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On (21/01/18 13:03), Timur Tabi wrote: > On 1/18/21 12:26 PM, Matthew Wilcox wrote: > > Don't make it easy. And don't make it look like they're doing > > something innocent. DUMP_PREFIX_SECURITY_HOLE would be OK > > by me. DUMP_PREFIX_LEAK_INFORMATION would work fine too. > > DUMP_PREFIX_MAKE_ATTACKERS_LIFE_EASY might be a bit too far. > > It's already extremely easy to replace %p with %px in your own printks, so I > don't really understand your argument. I like the idea of a more radical name, e.g. DUMP_PREFIX_RAW_POINTERS or something similar. > Seriously, this patch should not be so contentious. If you want hashed > addresses, then nothing changes. If you need unhashed addresses while > debugging, then use DUMP_PREFIX_UNHASHED. Just like you can use %px in > printk. I never use %p in my printks, but then I never submit code upstream > that prints addresses, hashed or unhashed. So maybe DUMP_PREFIX_UNHASHED can do the unhashed dump only when CONFIG_DEBUG_KERNEL=y and fallback to DUMP_PREFIX_ADDRESS otherwise? -ss