Re: [PATCH v2 2/3] usb: typec: tipd: Add an additional overflow check

[Heikki Krogerus]

On Tue, Sep 14, 2021 at 04:02:34PM +0200, Sven Peter wrote:
> tps6598x_block_read already checks for the maximum length of the read
> but tps6598x_block_write does not. Add the symmetric check there as
> well.
> 
> Signed-off-by: Sven Peter <sven@xxxxxxxxxxxxx>

Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>

> ---
> v1 -> v2:
>  - removed the WARN_ON to not crash machines running with panic-on-warn
>    as pointed out by greg k-h
> 
>  drivers/usb/typec/tipd/core.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/usb/typec/tipd/core.c b/drivers/usb/typec/tipd/core.c
> index c18ec3785592..8c79ba17a157 100644
> --- a/drivers/usb/typec/tipd/core.c
> +++ b/drivers/usb/typec/tipd/core.c
> @@ -139,6 +139,9 @@ static int tps6598x_block_write(struct tps6598x *tps, u8 reg,
>  {
>  	u8 data[TPS_MAX_LEN + 1];
>  
> +	if (len + 1 > sizeof(data))
> +		return -EINVAL;
> +
>  	if (!tps->i2c_protocol)
>  		return regmap_raw_write(tps->regmap, reg, val, len);
>  
> -- 
> 2.25.1

thanks,

-- 
heikki