From mboxrd@z Thu Jan 1 00:00:00 1970 From: joeyli Subject: Re: [PATCH] efivarfs: fix abnormal GUID in variable name by using strcpy to replace null with dash Date: Fri, 01 Mar 2013 22:49:35 +0800 Message-ID: <1362149375.23932.167.camel@linux-s257.site> References: <1362108018-13117-1-git-send-email-jlee@suse.com> <5130757F.4090702@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <5130757F.4090702-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Lingzhu Xiang Cc: matt-HNK1S37rvNbeXh+fF434Mdi2O/JbrIOy@public.gmane.org, linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Michael Schroeder , Josh Boyer , Jeremy Kerr List-Id: linux-efi@vger.kernel.org =E6=96=BC =E4=BA=94=EF=BC=8C2013-03-01 =E6=96=BC 17:31 +0800=EF=BC=8CLi= ngzhu Xiang =E6=8F=90=E5=88=B0=EF=BC=9A > On 03/01/2013 11:20 AM, Lee, Chun-Yi wrote: > > From: Michael Schroeder > >=20 > > On HP z220 system (firmware version 1.54), some EFI variables are i= ncorrectly > > named : > >=20 > > ls -d /sys/firmware/efi/vars/*8be4d* | grep -v -- -8be returns > > /sys/firmware/efi/vars/dbxDefault-pport8be4df61-93ca-11d2-aa0d-00e0= 98032b8c > > /sys/firmware/efi/vars/KEKDefault-pport8be4df61-93ca-11d2-aa0d-00e0= 98032b8c > > /sys/firmware/efi/vars/SecureBoot-pport8be4df61-93ca-11d2-aa0d-00e0= 98032b8c > > /sys/firmware/efi/vars/SetupMode-Information8be4df61-93ca-11d2-aa0d= -00e098032b8c > >=20 > > That causes by the following statement in efivar_create_sysfs_entry= function: > >=20 > > *(short_name + strlen(short_name)) =3D '-'; > > efi_guid_unparse(vendor_guid, short_name + strlen(short_name)); > >=20 > > The trailing \0 is overwritten with '-', but the next char doesn't = seem to be a \0 > > as well for HP. So, the second strlen return the point of next '\0'= , causes there > > have garbage string attached before GUID. > >=20 > > Tested on On HP z220. >=20 > So short_name has trailing garbage, or rather, variable_name_size > is larger than variable_name actually is, wouldn't new_efivar->var.Va= riableName > also gets filled with trailing garbage? >=20 > In efivar_store_raw the VariableName's trailing garbage can cause > problem for comparison. You might want to also cover that or fix > variable_name_size. >=20 >=20 > Lingzhu Xiang >=20 Yes, it's possible! I will add patch for print more debug messages to bug reporter for check it. Thanks for your review! Joey Lee From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751699Ab3CAOus (ORCPT ); Fri, 1 Mar 2013 09:50:48 -0500 Received: from smtp.nue.novell.com ([195.135.221.5]:38990 "EHLO smtp.nue.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751197Ab3CAOuq (ORCPT ); Fri, 1 Mar 2013 09:50:46 -0500 Subject: Re: [PATCH] efivarfs: fix abnormal GUID in variable name by using strcpy to replace null with dash From: joeyli To: Lingzhu Xiang Cc: matt@console-pimps.org, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, Michael Schroeder , Josh Boyer , Jeremy Kerr In-Reply-To: <5130757F.4090702@redhat.com> References: <1362108018-13117-1-git-send-email-jlee@suse.com> <5130757F.4090702@redhat.com> Content-Type: text/plain; charset="UTF-8" Date: Fri, 01 Mar 2013 22:49:35 +0800 Message-ID: <1362149375.23932.167.camel@linux-s257.site> Mime-Version: 1.0 X-Mailer: Evolution 2.28.2 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 於 五，2013-03-01 於 17:31 +0800，Lingzhu Xiang 提到： > On 03/01/2013 11:20 AM, Lee, Chun-Yi wrote: > > From: Michael Schroeder > > > > On HP z220 system (firmware version 1.54), some EFI variables are incorrectly > > named : > > > > ls -d /sys/firmware/efi/vars/*8be4d* | grep -v -- -8be returns > > /sys/firmware/efi/vars/dbxDefault-pport8be4df61-93ca-11d2-aa0d-00e098032b8c > > /sys/firmware/efi/vars/KEKDefault-pport8be4df61-93ca-11d2-aa0d-00e098032b8c > > /sys/firmware/efi/vars/SecureBoot-pport8be4df61-93ca-11d2-aa0d-00e098032b8c > > /sys/firmware/efi/vars/SetupMode-Information8be4df61-93ca-11d2-aa0d-00e098032b8c > > > > That causes by the following statement in efivar_create_sysfs_entry function: > > > > *(short_name + strlen(short_name)) = '-'; > > efi_guid_unparse(vendor_guid, short_name + strlen(short_name)); > > > > The trailing \0 is overwritten with '-', but the next char doesn't seem to be a \0 > > as well for HP. So, the second strlen return the point of next '\0', causes there > > have garbage string attached before GUID. > > > > Tested on On HP z220. > > So short_name has trailing garbage, or rather, variable_name_size > is larger than variable_name actually is, wouldn't new_efivar->var.VariableName > also gets filled with trailing garbage? > > In efivar_store_raw the VariableName's trailing garbage can cause > problem for comparison. You might want to also cover that or fix > variable_name_size. > > > Lingzhu Xiang > Yes, it's possible! I will add patch for print more debug messages to bug reporter for check it. Thanks for your review! Joey Lee