linux-kernel - Re: Regression from efi: call get_event

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: <CA+zpnLdiqvRcsjbVW248LQHr13NBTLd8bo1dY0T_sc+yhh9itg@mail.gmail.com>
Date:   Tue, 13 Mar 2018 15:00:22 +0000
From:   Thiebaud Weksteen <tweek@...gle.com>
To:     Ard Biesheuvel <ard.biesheuvel@...aro.org>, hdegoede@...hat.com,
        Jeremy Cline <jeremy@...ine.org>
Cc:     Javier Martinez Canillas <javierm@...hat.com>,
        Jarkko Sakkinen <jarkko.sakkinen@...ux.intel.com>,
        linux-efi@...r.kernel.org, linux-integrity@...r.kernel.org,
        tpmdd-devel@...ts.sourceforge.net, linux-kernel@...r.kernel.org
Subject: Re: Regression from efi: call get_event_log before ExitBootServices

On Tue, Mar 13, 2018 at 2:43 PM Ard Biesheuvel <ard.biesheuvel@...aro.org>
wrote:

> On 13 March 2018 at 13:41, Jeremy Cline <jeremy@...ine.org> wrote:
> > On 03/13/2018 03:59 AM, Ard Biesheuvel wrote:
> >> On 13 March 2018 at 07:47, Hans de Goede <hdegoede@...hat.com> wrote:
> >>> Hi,
> >>>
> >>>
> >>> On 12-03-18 20:55, Thiebaud Weksteen wrote:
> >>>>
> >> ...
> >>>>
> >>>> Hans, you said you configured the tablet to use the 32-bit version
of grub
> >>>> instead
> >>>> of 64. Why's that?
> >>>
> >>>
> >>> Because this tablet, like (almost?) all Bay Trail hardware has a 32
bit
> >>> UEFI,
> >>> even though the processor is 64 bit capable (AFAIK 64 bit Windows
drivers
> >>> were
> >>> not ready in time so all Bay Trail devices shipped with a 32 bit
Windows).
> >>>
> >>> So this is running a 32 bit grub which boots a 64 bit kernel.
> >>>
> >>>> Jeremy, could you confirm if you are building the kernel in 64bit
mode? Is
> >>>> your Android install working? (that is, what happens if you boot
> >>>> Boot0000)?
> >>>
> >>>
> >>> AFAIK the kernel on Jeremy's tablet (which I initially installed) is
64 bit.
> >>>
> >>> Could the problem perhaps be that the new code for the TPM event-log
is
> >>> missing some handling to deal with running on a 32 bit firmware? I
know the
> >>> rest of the kernel has special code to deal with this.
> >>>
> >>
> >> That is a very good point, and I missed that this is a 64-bit kernel
> >> running on 32-bit UEFI.
> >>
> >> The TPM code does use efi_call_proto() directly, and now I am thinking
> >> it is perhaps the allocate_pages() call that simply only initializes
> >> the low 32-bits of log_tbl.
> >>
> >> Jeremy, could you please try initializing tcg2_protocol and log_tbl to
> >> NULL at the start of the function?
> >>
> >
> > That was it, it boots when those are initialized to NULL.
> >

> Thanks for confirming. I'll send out a patch.

Sweet!
Jeremy, Hans, thanks for the help debugging!
Ard, thanks for the help fixing the issue!