From patchwork Wed Mar 4 21:32:53 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yinghai Lu X-Patchwork-Id: 446443 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id F03A4140187 for ; Thu, 5 Mar 2015 08:33:09 +1100 (AEDT) Authentication-Results: ozlabs.org; dkim=fail reason="verification failed; unprotected key" header.d=gmail.com header.i=@gmail.com header.b=XYCm+gNz; dkim-adsp=none (unprotected policy); dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752954AbbCDVc5 (ORCPT ); Wed, 4 Mar 2015 16:32:57 -0500 Received: from mail-ig0-f173.google.com ([209.85.213.173]:34455 "EHLO mail-ig0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752936AbbCDVcy (ORCPT ); Wed, 4 Mar 2015 16:32:54 -0500 Received: by igal13 with SMTP id l13so37030866iga.1; Wed, 04 Mar 2015 13:32:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; bh=ibBW7GtJigi2/mxAGklPJIJnzB6JqPSY60rCILsIpws=; b=XYCm+gNzIKEgkHWYGBPxV6OnDYgXrH2gleEQrybPDCnt+bOL7dm5IV/3TnPY8t/EiO ImZphY4eOz8XAJpfXVwA06WOoccOSY8T+TTn5lESA/aL94+95ADy02hakczMIiOWBVVM Lh2U5NaKq8jK+k8ITdNy1Gu/vyFpY9619VOjZzwSLGSp9xmRQJAdc0PGyr0FtFeusjzV 9fahTuIF3b3hwTqUA29iAX9Ov9Ru7yiH+MW4iprtKaDowe1PmNFOAlLH7qr6nVHlX9TW 7vwEtHkYDHVU3nQ0QfxOlvjTJw4bqEUH0NWMbd3S1unBPBCWChJAQ5NkdtB7kmYPPYA5 AJGg== MIME-Version: 1.0 X-Received: by 10.50.66.212 with SMTP id h20mr19000020igt.43.1425504773377; Wed, 04 Mar 2015 13:32:53 -0800 (PST) Received: by 10.64.208.43 with HTTP; Wed, 4 Mar 2015 13:32:53 -0800 (PST) In-Reply-To: <20150304200000.GB6276@gmail.com> References: <1425456048-16236-1-git-send-email-yinghai@kernel.org> <1425456048-16236-5-git-send-email-yinghai@kernel.org> <20150304101649.GA3663@pd.tnic> <20150304200000.GB6276@gmail.com> Date: Wed, 4 Mar 2015 13:32:53 -0800 X-Google-Sender-Auth: GSdaasiPpHqzCNW7sbqXx_jdbjA Message-ID: Subject: Re: [PATCH v2 04/15] x86, kaslr: get kaslr_enabled back correctly From: Yinghai Lu To: Ingo Molnar Cc: Borislav Petkov , Matt Fleming , "H. Peter Anvin" , Bjorn Helgaas , Thomas Gleixner , Ingo Molnar , Jiri Kosina , Borislav Petkov , Baoquan He , Linux Kernel Mailing List , "linux-efi@vger.kernel.org" , "linux-pci@vger.kernel.org" , Kees Cook Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wed, Mar 4, 2015 at 12:00 PM, Ingo Molnar wrote: > > It is totally unacceptable that you don't do proper analysis of the > patches you submit, and that you don't bother writing proper, readable > changelogs. Sorry, please check it again: Subject: [PATCH v4] x86, kaslr: Get kaslr_enabled back correctly commit f47233c2d34f ("x86/mm/ASLR: Propagate base load address calculation") is using address as value for kaslr_enabled. That will get wrong value back for kaslr_enabled in kernel stage. 1. When kaslr is not enabled at boot/choose_kernel_location, if kaslr_enabled get set wrongly in setup.c, late in module.c::get_module_load_offset will return not wanted random module load offset. That change behavior when HIBERNATION is defined or nokaslr is passed. 2. When kaslr is enabled at boot/choose_kernel_location, if kaslr_enabled get cleared wrongly in setup.c, late in module.c::get_module_load_offset will not return wanted random module load offset. This patch changes the code to use early_memmap and access the value, and will keep boot and kernel consistent with kaslr. -v3: add checking return from early_memmap according to bp. Fixes: f47233c2d34f ("x86/mm/ASLR: Propagate base load address calculation") Cc: Matt Fleming Cc: Borislav Petkov Cc: Kees Cook Cc: Jiri Kosina Acked-by: Jiri Kosina Signed-off-by: Yinghai Lu --- arch/x86/kernel/setup.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Index: linux-2.6/arch/x86/kernel/setup.c =================================================================== --- linux-2.6.orig/arch/x86/kernel/setup.c +++ linux-2.6/arch/x86/kernel/setup.c @@ -429,7 +429,18 @@ static void __init reserve_initrd(void) static void __init parse_kaslr_setup(u64 pa_data, u32 data_len) { - kaslr_enabled = (bool)(pa_data + sizeof(struct setup_data)); + /* kaslr_setup_data is defined in aslr.c */ + unsigned char *data; + unsigned long offset = sizeof(struct setup_data); + + data = early_memremap(pa_data, offset + 1); + if (!data) { + kaslr_enabled = true; + return; + } + + kaslr_enabled = *(data + offset); + early_memunmap(data, offset + 1); } static void __init parse_setup_data(void)