Re: [PATCH 0/4] KEYS: validate key trust with owner and builtin keys only

Dmitry Kasatkin
2014-06-10T21:17:56Z

On 11 June 2014 00:00, Dmitry Kasatkin <dmitry.kasatkin@gmail.com> wrote:
> On 10 June 2014 23:40, Matthew Garrett <mjg59@srcf.ucam.org> wrote:
>> On Tue, Jun 10, 2014 at 11:34:17PM +0300, Dmitry Kasatkin wrote:
>>
>>> Preventing loading keys from uefi except dbx by default actually improves
>>> security. Adding kernel parameter to read db we make system more
>>> vulnerable.
>>
>> It only adds security if you're performing a measured boot and remote
>> attestation. Otherwise you implicitly trust that key anyway. In almost
>> all cases refusing to trust db gives you a false sense of security
>> without any real improvement. I don't think it's obvious it should be
>> the default.
>>
>> --
>> Matthew Garrett | mjg59@srcf.ucam.org
>
> May be you are right... "in almost all cases"...
>
> It does not mater if one trust DB or not... It's all about
> distro/system configuration...
>
> Normal user even will not know what is default behavior and what
> kernel parameter disables or enables...
> And distro will have it by default or will use kernel parameter... It
> does not change anything...
>
> I am just discussing kernel configuration...
> Without kind of looking to it I cannot be sure if UEFI keys will
> appear on system keyring or not.
> Now I have to be aware how kernel is compiled... If it is compiled
> with CONFIG_KEYS_UEFI or so
> I need to remember may be to supply addition kernel parameters to
> limit key UEFI usage...
>
> It is may be not a big deal...
>
> --
> Thanks,
> Dmitry

It is probably just a paranoia...
Kconfig MODULE_SIG_UEFI should tell about threat of loading kernel
modules from NSA or Lenovo signed by MS or Lenovo keys..

This hole is opened without warning...

:)

--
Thanks,
Dmitry