Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752062AbaBKKH4 (ORCPT ); Tue, 11 Feb 2014 05:07:56 -0500 Received: from mx1.redhat.com ([209.132.183.28]:65022 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750767AbaBKKHr (ORCPT ); Tue, 11 Feb 2014 05:07:47 -0500 Date: Tue, 11 Feb 2014 18:08:38 +0800 From: Dave Young To: keescook@chromium.org, hpa@zytor.com, vgoyal@redhat.com, linux-kernel@vger.kernel.org Subject: [PATCH] disable kaslr in kdump kernel Message-ID: <20140211100837.GA17202@dhcp-16-126.nay.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org KASLR does not work in kdump kernel because it's too early that mem=exactmap has not been parsed. Since KASLR does not make much sense for kdump kernel thus let's disable it for kdump kernel. To check if it is a kdump kernel I just check the cmdline param elfcorehdr just like is_kdump_kernel. Signed-off-by: Dave Young --- linux-2.6/arch/x86/boot/compressed/aslr.c | 5 +++++ 1 file changed, 5 insertions(+) Index: dyoung/git/linux-2.6/arch/x86/boot/compressed/aslr.c =================================================================== --- linux-2.6/arch/x86/boot/compressed/aslr.c +++ linux-2.6/arch/x86/boot/compressed/aslr.c @@ -293,6 +293,11 @@ unsigned char *choose_kernel_location(un goto out; } + if (cmdline_find_option("elfcorehdr", NULL, 0) != -1) { + debug_putstr("KASLR disabled...\n"); + goto out; + } + /* Record the various known unsafe memory ranges. */ mem_avoid_init((unsigned long)input, input_size, (unsigned long)output, output_size); -- 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/