Re: [GIT PULL] Kernel lockdown for secure boot

From: Theodore Y. Ts'o
Date: Wed Apr 04 2018 - 09:53:05 EST


On Wed, Apr 04, 2018 at 02:33:37PM +0100, David Howells wrote:
> Theodore Y. Ts'o <tytso@xxxxxxx> wrote:
>
> > Whoa. Why doesn't lockdown prevent kexec? Put another away, why
> > isn't this a problem for people who are fearful that Linux could be
> > used as part of a Windows boot virus in a Secure UEFI context?
>
> Lockdown mode restricts kexec to booting an authorised image (where the
> authorisation may be by signature or by IMA).

If that's true, then Matthew's assertion that lockdown w/o secure boot
is insecure goes away, no?

- Ted