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

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: <CACE9dm8mfFvzS7qSHZFsodoiTHzba3AJF4kr2SrY20cNUiXrfQ@mail.gmail.com>
Date:	Wed, 11 Jun 2014 00:40:48 +0300
From:	Dmitry Kasatkin <dmitry.kasatkin@...il.com>
To:	Matthew Garrett <mjg59@...f.ucam.org>
Cc:	Josh Boyer <jwboyer@...hat.com>,
	David Howells <dhowells@...hat.com>,
	Mimi Zohar <zohar@...ux.vnet.ibm.com>,
	Dmitry Kasatkin <d.kasatkin@...sung.com>,
	keyrings <keyrings@...ux-nfs.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	linux-security-module <linux-security-module@...r.kernel.org>
Subject: Re: [PATCH 0/4] KEYS: validate key trust with owner and builtin keys only

On 11 June 2014 00:34, Dmitry Kasatkin <dmitry.kasatkin@...il.com> wrote:
> On 11 June 2014 00:25, Matthew Garrett <mjg59@...f.ucam.org> wrote:
>> On Wed, Jun 11, 2014 at 12:17:53AM +0300, Dmitry Kasatkin wrote:
>>
>>> 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...
>>
>> It's not typically a hole. If an attacker has root they can just replace
>> your bootloader with one signed by a trusted key and then have that
>> modify the kernel before booting it.
>>
>> If you're using a TPM then you can mitigate this, but if you have a TPM
>> then you're already performing some extra steps during the boot process.
>> Just add a sysfs knob that lets you drop the db keys and incorporate
>> that into the TPM management code.
>>
>> --
>> Matthew Garrett | mjg59@...f.ucam.org
>
> I was expecting this boot loader answer.
>
> Indeed, if system is design to prevent online modification of bootloader then
> kernel parameters are protected as well...
>
> My statement is still valid. It is a hole...
>
> To prevent the hole it should be explained that one might follow
> certain instructions
> to take ownership of your PC. Generate your own keys and remove MS and
> Vendor ones...
>
> It is paranoia? May be not.
>
> - Dmitry

I must admit that bootloader replacement is not related to kernel...

It is just paranoia...

- dmitry
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/