linux-kernel - Re: [GIT PULL] Kernel lockdown for secure boot

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: <CACdnJutkO9dgz=HZpPRR9PZC=+cHh97dRUiGB+D3gruZr6U9Kg@mail.gmail.com>
Date:   Tue, 03 Apr 2018 23:47:53 +0000
From:   Matthew Garrett <mjg59@...gle.com>
To:     Linus Torvalds <torvalds@...ux-foundation.org>
Cc:     luto@...nel.org, David Howells <dhowells@...hat.com>,
        Ard Biesheuvel <ard.biesheuvel@...aro.org>, jmorris@...ei.org,
        Alan Cox <gnomes@...rguk.ukuu.org.uk>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        jforbes@...hat.com, linux-man@...r.kernel.org, jlee@...e.com,
        LSM List <linux-security-module@...r.kernel.org>,
        linux-api@...r.kernel.org, Kees Cook <keescook@...omium.org>,
        linux-efi <linux-efi@...r.kernel.org>
Subject: Re: [GIT PULL] Kernel lockdown for secure boot

On Tue, Apr 3, 2018 at 4:39 PM Linus Torvalds
<torvalds@...ux-foundation.org>
wrote:

> On Tue, Apr 3, 2018 at 4:26 PM, Linus Torvalds
> <torvalds@...ux-foundation.org> wrote:
> >
> > Magically changing kernel behavior depending on some subtle and often
> > unintentional bootup behavior detail is completely idiotic.

> Another way of looking at this: if lockdown is a good idea to enable
> when you booted using secure boot, then why isn't it a good idea when
> you *didn't* boot using secure boot?

Because it's then trivial to circumvent and the restrictions aren't worth
the benefit.