Re: [PATCH] efi/tpm: Differentiate missing and invalid final event log table.

[Ard Biesheuvel <ardb@kernel.org>]

On Fri, 9 Jul 2021 at 18:38, Jarkko Sakkinen <jarkko@kernel.org> wrote:
>
> On Thu, Jul 08, 2021 at 11:46:54AM +0200, Michal Suchanek wrote:
> > Missing TPM final event log table is not a firmware bug.
> >
> > Clearly if providing event log in the old format makes the final event
> > log invalid it should not be provided at least in that case.
> >
> > Fixes: b4f1874c6216 ("tpm: check event log version before reading final events")
> > Signed-off-by: Michal Suchanek <msuchanek@suse.de>
> > ---
> >  drivers/firmware/efi/tpm.c | 8 +++++---
> >  1 file changed, 5 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/firmware/efi/tpm.c b/drivers/firmware/efi/tpm.c
> > index c1955d320fec..8f665678e9e3 100644
> > --- a/drivers/firmware/efi/tpm.c
> > +++ b/drivers/firmware/efi/tpm.c
> > @@ -62,9 +62,11 @@ int __init efi_tpm_eventlog_init(void)
> >       tbl_size = sizeof(*log_tbl) + log_tbl->size;
> >       memblock_reserve(efi.tpm_log, tbl_size);
> >
> > -     if (efi.tpm_final_log == EFI_INVALID_TABLE_ADDR ||
> > -         log_tbl->version != EFI_TCG2_EVENT_LOG_FORMAT_TCG_2) {
> > -             pr_warn(FW_BUG "TPM Final Events table missing or invalid\n");
> > +     if (efi.tpm_final_log == EFI_INVALID_TABLE_ADDR) {
> > +             pr_info("TPM Final Events table not present\n");
> > +             goto out;
> > +     } else if (log_tbl->version != EFI_TCG2_EVENT_LOG_FORMAT_TCG_2) {
> > +             pr_warn(FW_BUG "TPM Final Events table invalid\n");
> >               goto out;
> >       }
> >
> > --
> > 2.26.2
> >
> >
>
> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
>

Queued as a fix, thanks