All of lore.kernel.org
 help / color / mirror / Atom feed
From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To: Jerry Snitselaar <jsnitsel@redhat.com>
Cc: linux-integrity@vger.kernel.org, Matthew Garrett <mjg59@google.com>
Subject: Re: Disparity in tpm pcr5 value
Date: Wed, 13 May 2020 20:10:52 +0300	[thread overview]
Message-ID: <20200513171052.GD25598@linux.intel.com> (raw)
In-Reply-To: <20200505222731.whnkisag7tlrbcie@cantor>

On Tue, May 05, 2020 at 03:27:31PM -0700, Jerry Snitselaar wrote:
> On some systems we've had reports of the value of pcr5 doesn't match the digests in the tpm event log.
> It looks like I'm able to reproduce here with 5.7-rc4 on a dell system using this parser:
> 
> https://github.com/ValdikSS/binary_bios_measurements_parser
> 
> Any thoughts on where to start digging? Is there another tool I should use to parse this?

ExitBootServices() extends PCR5. My 1st intuition would be to look at
final event table handling, which I documented here:

https://www.kernel.org/doc/Documentation/security/tpm/tpm_event_log.rst

It is somewhat quirky how it nees to be managed (had to read that
myself to recall how it went).

/Jarkko

  parent reply	other threads:[~2020-05-13 17:10 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-05 22:27 Disparity in tpm pcr5 value Jerry Snitselaar
2020-05-06 14:12 ` Ken Goldman
2020-05-07  7:35   ` Jerry Snitselaar
2020-05-07 14:50     ` Mimi Zohar
2020-05-07 16:26       ` Jerry Snitselaar
2020-05-07 20:57         ` Mimi Zohar
2020-05-07 23:12           ` Jerry Snitselaar
2020-05-13 17:10 ` Jarkko Sakkinen [this message]
2020-05-13 17:59   ` Jerry Snitselaar
2020-05-14 11:03     ` Jarkko Sakkinen
2020-05-14 16:55       ` Jerry Snitselaar

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200513171052.GD25598@linux.intel.com \
    --to=jarkko.sakkinen@linux.intel.com \
    --cc=jsnitsel@redhat.com \
    --cc=linux-integrity@vger.kernel.org \
    --cc=mjg59@google.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.