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=-5.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_NEOMUTT 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 888F7C64EAD for ; Tue, 9 Oct 2018 14:05:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 597302087D for ; Tue, 9 Oct 2018 14:05:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 597302087D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726794AbeJIVWu (ORCPT ); Tue, 9 Oct 2018 17:22:50 -0400 Received: from mx2.suse.de ([195.135.220.15]:56464 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726564AbeJIVWt (ORCPT ); Tue, 9 Oct 2018 17:22:49 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 0B35FAD4C; Tue, 9 Oct 2018 14:05:41 +0000 (UTC) Date: Tue, 9 Oct 2018 16:05:40 +0200 From: Petr Mladek To: Geert Uytterhoeven Cc: Andy Shevchenko , "Tobin C . Harding" , Andrew Morton , Jonathan Corbet , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org Subject: Re: [PATCH 2/3] lib/vsprintf: Hash legacy clock addresses Message-ID: <20181009140540.mz77x5a7bfmupxbb@pathway.suse.cz> References: <20181008110504.25449-1-geert+renesas@glider.be> <20181008110504.25449-3-geert+renesas@glider.be> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181008110504.25449-3-geert+renesas@glider.be> User-Agent: NeoMutt/20170421 (1.8.2) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon 2018-10-08 13:05:03, Geert Uytterhoeven wrote: > On platforms using the Common Clock Framework, "%pC" prints the clock's > name. On legacy platforms, it prints the unhashed clock's address, > potentially leaking sensitive information regarding the kernel layout in > memory. > > Avoid this leak by printing the hashed address instead. To distinguish > between clocks, a 32-bit unique identifier is as good as an actual > pointer value. > > Fixes: ad67b74d2469d9b8 ("printk: hash addresses printed with %p") > Signed-off-by: Geert Uytterhoeven It makes sense. Reviewed-by: Petr Mladek Best Regards, Petr