Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753480AbaA0Gvq (ORCPT ); Mon, 27 Jan 2014 01:51:46 -0500 Received: from terminus.zytor.com ([198.137.202.10]:42518 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753329AbaA0Gvp (ORCPT ); Mon, 27 Jan 2014 01:51:45 -0500 Message-ID: <52E601DA.7010605@zytor.com> Date: Sun, 26 Jan 2014 22:51:06 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 MIME-Version: 1.0 To: Richard Weinberger , "H. Peter Anvin" CC: Linus Torvalds , Cong Ding , Ingo Molnar , Ingo Molnar , Kees Cook , Linux Kernel Mailing List , Mathias Krause , Michael Davidson , Thomas Gleixner , Wei Yongjun Subject: Re: [GIT PULL] x86/kaslr for v3.14 References: <201401201647.s0KGlZdh004167@tazenda.hos.anvin.org> <52E5EFAF.3060609@linux.intel.com> In-Reply-To: X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/26/2014 10:49 PM, Richard Weinberger wrote: >> >> No, because that information is available to user space unless we panic. > > Didn't you mean non-root? > I thought one has to set dmesg_restrict anyways if kASLR is used. > > And isn't the offset available to perf too? > Of course only for root, but still user space. > For certain system security levels one want to protect even from a rogue root. In those cases, leaking that information via dmesg and perf isn't going to work, either. With lower security settings, by all means... -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/