[PATCH] efi_loader: Do not show error message if TPM is not present

[Ilias Apalodimas]

Hi Michal,

On Mon, 29 Nov 2021 at 15:06, Michal Simek <michal.simek at xilinx.com> wrote:
>
> For systems which have TPM support enabled but actual device is missing
> there is no reason to show a message that measurement failed.
> That's why properly check error code which is returned.
>
> Signed-off-by: Michal Simek <michal.simek at xilinx.com>
> ---
>
>  lib/efi_loader/efi_image_loader.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/lib/efi_loader/efi_image_loader.c b/lib/efi_loader/efi_image_loader.c
> index eb95580538cc..c6a254dc25dd 100644
> --- a/lib/efi_loader/efi_image_loader.c
> +++ b/lib/efi_loader/efi_image_loader.c
> @@ -934,8 +934,9 @@ efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle,
>
>  #if CONFIG_IS_ENABLED(EFI_TCG2_PROTOCOL)
>         /* Measure an PE/COFF image */
> -       if (tcg2_measure_pe_image(efi, efi_size, handle,
> -                                 loaded_image_info))
> +       ret = tcg2_measure_pe_image(efi, efi_size, handle,
> +                                   loaded_image_info);
> +       if (ret && ret != EFI_NOT_FOUND)
>                 log_err("PE image measurement failed\n");
>  #endif

Indeed that's needed.  Looking at it again though maybe it's better to
add an identical check in tcg2_measure_pe_image() and return
EFI_SUCCESS if platform_get_tpm2_device() returned EFI_NOT_FOUND.  The
reason is that other parts of the code return EFI_NOT_FOUND in that
function (e.g efi_search_protocol).  So we need to make sure we report
the error in that case.


>
> --
> 2.33.1
>

Thanks
/Ilias