Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756165Ab3DXOog (ORCPT ); Wed, 24 Apr 2013 10:44:36 -0400 Received: from mail-wi0-f170.google.com ([209.85.212.170]:39633 "EHLO mail-wi0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756131Ab3DXOod (ORCPT ); Wed, 24 Apr 2013 10:44:33 -0400 Message-ID: <5177EFCE.80104@intel.com> Date: Wed, 24 Apr 2013 15:44:30 +0100 From: Matt Fleming Organization: Intel Corporation (UK) Ltd. - Registered No. 1134945 - Pipers Way, Swindon SN3 1RJ User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130329 Thunderbird/17.0.5 MIME-Version: 1.0 To: Josh Boyer CC: Matthew Garrett , linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] efi: Check EFI revision in setup_efi_vars References: <20130424143738.GB15272@hansolo.jdub.homelinux.org> In-Reply-To: <20130424143738.GB15272@hansolo.jdub.homelinux.org> 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 Content-Length: 1778 Lines: 41 On 24/04/13 15:37, Josh Boyer wrote: > We need to check the runtime sys_table for the EFI version the firmware > specifies instead of just checking for a NULL QueryVariableInfo. Older > implementations of EFI don't have QueryVariableInfo but the runtime is > a smaller structure, so the pointer to it may be pointing off into garbage. > > This is apparently the case with several Apple firmwares that support EFI > 1.10, and the current check causes them to no longer boot. Fix based on > a suggestion from Matthew Garrett. > > Signed-off-by: Josh Boyer > --- > arch/x86/boot/compressed/eboot.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c > index 8615f75..b46efbf 100644 > --- a/arch/x86/boot/compressed/eboot.c > +++ b/arch/x86/boot/compressed/eboot.c > @@ -258,7 +258,9 @@ static efi_status_t setup_efi_vars(struct boot_params *params) > u64 store_size, remaining_size, var_size; > efi_status_t status; > > - if (!sys_table->runtime->query_variable_info) > + if (sys_table->runtime->hdr.revision < EFI_2_00_SYSTEM_TABLE_REVISION) > + return EFI_UNSUPPORTED; > + else if(!sys_table->runtime->query_variable_info) > return EFI_UNSUPPORTED; > > data = (struct setup_data *)(unsigned long)params->hdr.setup_data; > Thanks Josh, that looks correct. It's a small point, but does the check against NULL actually make sense? I don't think we ever check other system table pointers against NULL. -- 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/