Message-ID: <1362664663.15011.194.camel@mfleming-mobl1.ger.corp.intel.com>
Subject: Re: [PATCH] efivarfs: fix abnormal GUID in variable name by using
 strcpy to replace null with dash
From: Matt Fleming <matt@console-pimps.org>
To: joeyli <jlee@suse.com>
Cc: linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org,
        Michael Schroeder <mls@suse.com>, Josh Boyer <jwboyer@redhat.com>,
        Peter Jones <pjones@redhat.com>, Matthew Garrett <mjg59@srcf.ucam.org>,
        Frederic Crozat <fcrozat@suse.com>
Date: Thu, 07 Mar 2013 13:57:43 +0000
In-Reply-To: <1362656348.15011.166.camel@mfleming-mobl1.ger.corp.intel.com>
References: <1362108018-13117-1-git-send-email-jlee@suse.com>
	 <1362151068.2842.440.camel@mfleming-mobl1.ger.corp.intel.com>
	 <1362155493.2842.446.camel@mfleming-mobl1.ger.corp.intel.com>
	 <1362181299.23932.168.camel@linux-s257.site>
	 <1362555258.23932.573.camel@linux-s257.site>
	 <1362568750.15011.24.camel@mfleming-mobl1.ger.corp.intel.com>
	 <1362652440.28562.26.camel@linux-s257.site>
	 <1362656348.15011.166.camel@mfleming-mobl1.ger.corp.intel.com>
Content-Type: text/plain; charset="UTF-8"
Mime-Version: 1.0
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1260
Lines: 29

On Thu, 2013-03-07 at 11:39 +0000, Matt Fleming wrote:
> On Thu, 2013-03-07 at 18:34 +0800, joeyli wrote:
> > The VariableNameSize is not reliable when EFI_SUCCESS is returned
> > because UEFI 2.3.1 spec only mention VariableNameSize should updated
> > when EFI_BUFFER_TOO_SMALL is returned. And, the 1024 bytes of buffer is
> > from old UEFI spec. There doesn't have any size condition of variable
> > data or variable name in 2.3.1 spec.
> 
> The spec may only mention what happens in the EFI_BUFFER_TOO_SMALL case,
> but for EFI_SUCCESS, any behaviour other than leaving VariableNameSize
> alone or updating it with the required size of the buffer is just
> completely insane.
> 
> > I modified the patch to grab VariableNameSize when EFI_BUFFER_TOO_SMALL,
> > the behavior like what we do in efivarfs_file_read().
> 
> Thanks, this does seem like the most robust solution.

Also, you're probably going to need to update
efivar_update_sysfs_entries() too.

-- 
Matt Fleming, Intel Open Source Technology Center

--
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/