From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ingo Molnar Subject: Re: [PATCH] x86/acpi: check rsdp address received via bootparams to be valid Date: Tue, 16 Jan 2018 16:46:30 +0100 Message-ID: <20180116154630.ke53suvokynj73qd@gmail.com> References: <20180116135730.19216-1-jgross@suse.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-wm0-f66.google.com ([74.125.82.66]:42423 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750981AbeAPPqf (ORCPT ); Tue, 16 Jan 2018 10:46:35 -0500 Content-Disposition: inline In-Reply-To: <20180116135730.19216-1-jgross@suse.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Juergen Gross Cc: linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, x86@kernel.org, lenb@kernel.org, rafael.j.wysocki@intel.com, hpa@zytor.com, tglx@linutronix.de, mingo@redhat.com * Juergen Gross wrote: > There seem to exist several grub2 versions trashing > boot_params.hdr.acpi_rsdp_addr. > > So don't just believe this address to be valid, but verify it pointing > to a valid RSDP table. Exactly what kind of values do those Grub2 versions put into that field? Pointer to something, or random noise? Also, what exactly does 'validation' mean, how robustly does it filter out of spec uses of the boot protocol? Thanks, Ingo