Re: [PATCH 5/6] platform/chrome: cros_ec_i2c: drop BUG_ON() in cros_ec_pkt_xfer_i2c()

[Guenter Roeck]

On Thu, May 12, 2022 at 1:36 AM Tzung-Bi Shih <tzungbi@xxxxxxxxxx> wrote:
>
> It is overkill to crash the kernel if the given message is oversize.
>
> Drop the BUG_ON() and return -EINVAL instead.
>
> Signed-off-by: Tzung-Bi Shih <tzungbi@xxxxxxxxxx>

Reviewed-by: Guenter Roeck <groeck@xxxxxxxxxxxx>

> ---
>  drivers/platform/chrome/cros_ec_i2c.c | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/platform/chrome/cros_ec_i2c.c b/drivers/platform/chrome/cros_ec_i2c.c
> index a4f305f1eb0e..9f5b95763173 100644
> --- a/drivers/platform/chrome/cros_ec_i2c.c
> +++ b/drivers/platform/chrome/cros_ec_i2c.c
> @@ -72,13 +72,19 @@ static int cros_ec_pkt_xfer_i2c(struct cros_ec_device *ec_dev,
>         i2c_msg[1].flags = I2C_M_RD;
>
>         packet_len = msg->insize + response_header_size;
> -       BUG_ON(packet_len > ec_dev->din_size);
> +       if (packet_len > ec_dev->din_size) {
> +               ret = -EINVAL;
> +               goto done;
> +       }
>         in_buf = ec_dev->din;
>         i2c_msg[1].len = packet_len;
>         i2c_msg[1].buf = (char *) in_buf;
>
>         packet_len = msg->outsize + request_header_size;
> -       BUG_ON(packet_len > ec_dev->dout_size);
> +       if (packet_len > ec_dev->dout_size) {
> +               ret = -EINVAL;
> +               goto done;
> +       }
>         out_buf = ec_dev->dout;
>         i2c_msg[0].len = packet_len;
>         i2c_msg[0].buf = (char *) out_buf;
> --
> 2.36.0.512.ge40c2bad7a-goog
>