Re: [PATCH] media: dw2102: fix a potential buffer overflow

From: Hans Verkuil
Date: Mon Apr 29 2024 - 10:24:41 EST


On 29/04/2024 16:17, Mauro Carvalho Chehab wrote:
> As pointed by smatch:
> drivers/media/usb/dvb-usb/dw2102.c:802 su3000_i2c_transfer() error: __builtin_memcpy() '&state->data[4]' too small (64 vs 67)
>
> That seemss to be due to a wrong copy-and-paste.
>
> Reported-by: Hans Verkuil <hverkuil@xxxxxxxxx>
> Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>

Reviewed-by: Hans Verkuil <hverkuil@xxxxxxxxx>

Regards,

Hans

> ---
> drivers/media/usb/dvb-usb/dw2102.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/media/usb/dvb-usb/dw2102.c b/drivers/media/usb/dvb-usb/dw2102.c
> index 03b411ad64bb..79e2ccf974c9 100644
> --- a/drivers/media/usb/dvb-usb/dw2102.c
> +++ b/drivers/media/usb/dvb-usb/dw2102.c
> @@ -789,7 +789,7 @@ static int su3000_i2c_transfer(struct i2c_adapter *adap, struct i2c_msg msg[],
>
> if (msg[j].flags & I2C_M_RD) {
> /* single read */
> - if (1 + msg[j].len > sizeof(state->data)) {
> + if (4 + msg[j].len > sizeof(state->data)) {
> warn("i2c rd: len=%d is too big!\n", msg[j].len);
> num = -EOPNOTSUPP;
> break;