Re: [PATCH v3] media: davinci vpbe: array underflow in vpbe_enum_outputs()

Lad, Prabhakar
2018-05-29T19:54:51Z

On Mon, May 28, 2018 at 7:26 AM, Dan Carpenter <dan.carpenter@oracle.com> wrote:
> In vpbe_enum_outputs() we check if (temp_index >= cfg->num_outputs) but
> the problem is that temp_index can be negative. I've changed the types
> to unsigned to fix this issue.
>
> Fixes: 66715cdc3224 ("[media] davinci vpbe: VPBE display driver")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> v2: fix it a different way
> v3: change everything to unsigned because that's the right thing to do
> and looks nicer.
>

Acked-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>

Regards,
--Prabhakar Lad

> diff --git a/include/media/davinci/vpbe.h b/include/media/davinci/vpbe.h
> index 79a566d7defd..180a05e91497 100644
> --- a/include/media/davinci/vpbe.h
> +++ b/include/media/davinci/vpbe.h
> @@ -92,7 +92,7 @@ struct vpbe_config {
> struct encoder_config_info *ext_encoders;
> /* amplifier information goes here */
> struct amp_config_info *amp;
> - int num_outputs;
> + unsigned int num_outputs;
> /* Order is venc outputs followed by LCD and then external encoders */
> struct vpbe_output *outputs;
> };
> diff --git a/drivers/media/platform/davinci/vpbe.c b/drivers/media/platform/davinci/vpbe.c
> index 18c035ef84cf..c6fee53bff4d 100644
> --- a/drivers/media/platform/davinci/vpbe.c
> +++ b/drivers/media/platform/davinci/vpbe.c
> @@ -126,7 +126,7 @@ static int vpbe_enum_outputs(struct vpbe_device *vpbe_dev,
> struct v4l2_output *output)
> {
> struct vpbe_config *cfg = vpbe_dev->cfg;
> - int temp_index = output->index;
> + unsigned int temp_index = output->index;
>
> if (temp_index >= cfg->num_outputs)
> return -EINVAL;