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=-8.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 B4289C433E0 for ; Thu, 11 Feb 2021 18:17:01 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 316DB64E13 for ; Thu, 11 Feb 2021 18:17:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 316DB64E13 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A6BE66B0145; Thu, 11 Feb 2021 13:17:00 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id A1A3E6B0146; Thu, 11 Feb 2021 13:17:00 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9093F6B0147; Thu, 11 Feb 2021 13:17:00 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0245.hostedemail.com [216.40.44.245]) by kanga.kvack.org (Postfix) with ESMTP id 77F056B0145 for ; Thu, 11 Feb 2021 13:17:00 -0500 (EST) Received: from smtpin21.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 3F8D81EE6 for ; Thu, 11 Feb 2021 18:17:00 +0000 (UTC) X-FDA: 77806793400.21.pull10_1809b412761a Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin21.hostedemail.com (Postfix) with ESMTP id 1ADC3180442C2 for ; Thu, 11 Feb 2021 18:17:00 +0000 (UTC) X-HE-Tag: pull10_1809b412761a X-Filterd-Recvd-Size: 3152 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf33.hostedemail.com (Postfix) with ESMTP for ; Thu, 11 Feb 2021 18:16:59 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 8DD4764E5F; Thu, 11 Feb 2021 18:16:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1613067418; bh=a9Mage+YDe1nKc3ePEl7r91KB9eDjlkq0mBjRYUgY7Y=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=MGYKNQBRn+TnI7ZLBVEERLlb/VuyR4+19I141SQ4UHwoe8Ibml0lrpZYdUT8CNwqU IuEXpq/g6ui86KXEdSLX7ORPuV9DDI9yDHer/ioujj4ftQNAGaKE5CTwUBI12S54KQ PGhq5XDqi1PIcbWb//k7XAfu8KYc8IKb4Mcibk6FaW3nMCAdhbficNqJrULLCQRiiR rtFMSE10Iyban/U7OAPBOdSn8Lk4LtIR3ra7LbIBpemVtfi1NjhJkjR9NivfmwpqDG nW3IdU4oaDtj2rOU9Cqd44nLKXmUTgrFai1sT051jVAR8NopOBGYQhC+tvqmrK9bEb GfYg9W6yd7mcg== Subject: Re: [PATCH 3/3] [v3] lib/vsprintf: debug_never_hash_pointers prints all addresses as unhashed To: Petr Mladek Cc: Steven Rostedt , Sergey Senozhatsky , Vlastimil Babka , Andy Shevchenko , Matthew Wilcox , akpm@linux-foundation.org, Linus Torvalds , roman.fietze@magna.com, Kees Cook , John Ogness , akinobu.mita@gmail.com, glider@google.com, Andrey Konovalov , Marco Elver , Rasmus Villemoes , Pavel Machek , Tetsuo Handa , linux-kernel@vger.kernel.org, linux-mm@kvack.org References: <20210210213453.1504219-1-timur@kernel.org> <20210210213453.1504219-4-timur@kernel.org> From: Timur Tabi Message-ID: <4a233bef-8ba6-82bb-9075-35793a244a3b@kernel.org> Date: Thu, 11 Feb 2021 12:16:55 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit 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 2/11/21 11:53 AM, Petr Mladek wrote: > I would really like to make it clear here that it is not only about > consoles. Most people will see only this message. Only few people read > documentation. Many people will learn the parameter name from another > context by googling. > > I know that it is not easy to find good words. Especially because > pointers printed by %pK might still be hashed. > >> + pr_warn("** **\n"); >> + pr_warn("** Kernel memory addresses are exposed, which may **\n"); >> + pr_warn("** reduce the security of your system. **\n"); > What about replacing the first two paragraphs with something like: > > "This system shows unhashed kernel memory addresses via logs and > other interfaces. It might reduce the security of your system." That works, thanks. I'll post a v4 soon.