Re: [PATCH v3 20/23] platform/chrome: cros_ec_proto: handle empty payload in getting cmd mask

[Guenter Roeck]

On Wed, Jun 8, 2022 at 4:08 AM Tzung-Bi Shih <tzungbi@xxxxxxxxxx> wrote:
>
> cros_ec_get_host_command_version_mask() expects to receive
> sizeof(struct ec_response_get_cmd_versions) from send_command().  The
> payload is valid only if the return value is positive.
>
> Return -EPROTO if send_command() returns 0 in
> cros_ec_get_host_command_version_mask().
>
> Signed-off-by: Tzung-Bi Shih <tzungbi@xxxxxxxxxx>

That answers my previous question.

Reviewed-by: Guenter Roeck <groeck@xxxxxxxxxxxx>

> ---
> No v2.  New and separated from the original series.
>
>  drivers/platform/chrome/cros_ec_proto.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c
> index 6a5771361383..9e95f9e4b2f8 100644
> --- a/drivers/platform/chrome/cros_ec_proto.c
> +++ b/drivers/platform/chrome/cros_ec_proto.c
> @@ -458,6 +458,11 @@ static int cros_ec_get_host_command_version_mask(struct cros_ec_device *ec_dev,
>                 goto exit;
>         }
>
> +       if (ret == 0) {
> +               ret = -EPROTO;
> +               goto exit;
> +       }
> +
>         rver = (struct ec_response_get_cmd_versions *)msg->data;
>         *mask = rver->version_mask;
>         ret = 0;
> --
> 2.36.1.255.ge46751e96f-goog
>