linux-kernel - Re: [PATCH] efi: Do not import certificates from UEFI Secure Boot for T2 Macs

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: <20220212194240.GA4131@srcf.ucam.org>
Date:   Sat, 12 Feb 2022 19:42:40 +0000
From:   Matthew Garrett <mjg59@...f.ucam.org>
To:     Aditya Garg <gargaditya08@...e.com>
Cc:     Ard Biesheuvel <ardb@...nel.org>, Jeremy Kerr <jk@...abs.org>,
        "joeyli.kernel@...il.com" <joeyli.kernel@...il.com>,
        "zohar@...ux.ibm.com" <zohar@...ux.ibm.com>,
        "jmorris@...ei.org" <jmorris@...ei.org>,
        "eric.snowberg@...cle.com" <eric.snowberg@...cle.com>,
        "dhowells@...hat.com" <dhowells@...hat.com>,
        "jlee@...e.com" <jlee@...e.com>,
        "James.Bottomley@...senpartnership.com" 
        <James.Bottomley@...senPartnership.com>,
        "jarkko@...nel.org" <jarkko@...nel.org>,
        "mic@...ikod.net" <mic@...ikod.net>,
        "dmitry.kasatkin@...il.com" <dmitry.kasatkin@...il.com>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        "linux-efi@...r.kernel.org" <linux-efi@...r.kernel.org>,
        "linux-security-module@...r.kernel.org" 
        <linux-security-module@...r.kernel.org>,
        "stable@...r.kernel.org" <stable@...r.kernel.org>,
        "keyrings@...r.kernel.org" <keyrings@...r.kernel.org>,
        "linux-integrity@...r.kernel.org" <linux-integrity@...r.kernel.org>,
        Orlando Chamberlain <redecorating@...tonmail.com>,
        Aun-Ali Zaidi <admin@...eit.net>
Subject: Re: [PATCH] efi: Do not import certificates from UEFI Secure Boot
 for T2 Macs

On Sat, Feb 12, 2022 at 05:53:47AM +0000, Aditya Garg wrote:

> Feb 12 11:01:52 MacBook kernel: Reading EFI variable db-d719b2cb-3d3a-4596-a3bc-dad00e67656f

Ok. With CONFIG_LOAD_UEFI_KEYS=n, can you run:

cat /sys/firmware/efi/efivars/db-d719b2cb-3d3a-4596-a3bc-dad00e67656f

and see whether it generates the same failure? If so then my (handwavy) 
guess is that something's going wrong with a firmware codepath for the 
d719b2cb-3d3a-4596-a3bc-dad00e67656f GUID. Someone could potentially 
then figure out whether the same happens under Windows, but the easiest 
thing is probably to just return a failure on Apple hardware when 
someone tries to access anything with that GUID.