linux-kernel - Re: [PATCH 8/8] efi: pstore: Add module parameter for setting the record size

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <cc5945c8-3aa6-980d-902f-ac72f1f3902c@igalia.com>
Date:   Fri, 7 Oct 2022 20:29:55 -0300
From:   "Guilherme G. Piccoli" <gpiccoli@...lia.com>
To:     Kees Cook <keescook@...omium.org>
Cc:     Ard Biesheuvel <ardb@...nel.org>, linux-kernel@...r.kernel.org,
        linux-fsdevel@...r.kernel.org, kernel-dev@...lia.com,
        kernel@...ccoli.net, anton@...msg.org, ccross@...roid.com,
        tony.luck@...el.com, linux-efi@...r.kernel.org
Subject: Re: [PATCH 8/8] efi: pstore: Add module parameter for setting the
 record size

On 07/10/2022 16:32, Kees Cook wrote:
> [...]
> Given OVMF showing this as a max, it doesn't seem right to also make
> this a minimum? Perhaps choose a different minimum to be enforced.

Hi Kees! Through my tests, I've noticed low values tend to cause issues
(didn't go further in the investigation), IIRC even 512 caused problems
on "deflate" (worked in the others).

I'll try again 512 to see how it goes, but I'm not so sure what would be
the use of such low values, it does truncate a lot and "pollute" the
pstore fs with many small files. But I can go with any value you/Ard
think is appropriate (given it works with all compression algorithms
heh) - currently the minimum of 1024 is enforced in the patch.

> 
> Also, can you update the commit log with Ard's archeology on
> gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize ?
> 

Sure, of course!
Cheers,

Guilherme