[SeaBIOS] Re: [PATCH 1/2] tpm: Require a response to have minimum size of a valid response header

[Marc-André Lureau]

On Thu, Nov 7, 2019 at 1:51 AM Stefan Berger  wrote:
> Defend against a broken TPM 1.2 or TPM 2.0 that doesn't send at least
> a full response header in the response but less than 10 bytes.
>
> Signed-off-by: Stefan Berger

Reviewed-by: Marc-André Lureau
> src/hw/tpm_drivers.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/src/hw/tpm_drivers.c b/src/hw/tpm_drivers.c
> index e4770b3..2b5753c 100644
> --- a/src/hw/tpm_drivers.c
> +++ b/src/hw/tpm_drivers.c
> @@ -620,7 +620,8 @@ tpmhw_transmit(u8 locty, struct tpm_req_header *req,
>          return -1;
>  irc = td->readresp(respbuffer, respbufferlen);
> if (irc != 0)
>
> if (irc != 0 ||
>    *respbufferlen < sizeof(struct tpm_rsp_header))
>    return -1;
>
> td->ready();