Re: [PATCH v3 1/9] media: v4l2-ctrls: validate HEVC tile counts

[Benjamin Gaignard <benjamin.gaignard@collabora.com>]

Le 17/06/2026 à 04:18, Michael Bommarito a écrit :
> The stateless HEVC decoders read num_tile_columns_minus1 + 1 entries from
> column_width_minus1[] and num_tile_rows_minus1 + 1 from row_height_minus1[]
> and use them as tile-loop bounds, but std_validate_compound() does not
> bound these u8 counts. Reject a V4L2_CTRL_TYPE_HEVC_PPS with tiling
> enabled whose tile counts exceed the uAPI array capacity, mirroring the
> existing compound-control range checks.
>
> Fixes: 256fa3920874 ("media: v4l: Add definitions for HEVC stateless decoding")
> Assisted-by: Claude:claude-opus-4-8
> Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>

Reviewed-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>

> ---
>   drivers/media/v4l2-core/v4l2-ctrls-core.c | 12 ++++++++++++
>   1 file changed, 12 insertions(+)
>
> diff --git a/drivers/media/v4l2-core/v4l2-ctrls-core.c b/drivers/media/v4l2-core/v4l2-ctrls-core.c
> index 6b375720e395c..6d478e1a5ef22 100644
> --- a/drivers/media/v4l2-core/v4l2-ctrls-core.c
> +++ b/drivers/media/v4l2-core/v4l2-ctrls-core.c
> @@ -1242,6 +1242,18 @@ static int std_validate_compound(const struct v4l2_ctrl *ctrl, u32 idx,
>   
>   			p_hevc_pps->flags &=
>   				~V4L2_HEVC_PPS_FLAG_LOOP_FILTER_ACROSS_TILES_ENABLED;
> +		} else {
> +			/*
> +			 * These count the entries the stateless HEVC drivers
> +			 * read from column_width_minus1[] / row_height_minus1[]
> +			 * and use as tile-loop bounds.
> +			 */
> +			if (p_hevc_pps->num_tile_columns_minus1 >=
> +			    ARRAY_SIZE(p_hevc_pps->column_width_minus1))
> +				return -EINVAL;
> +			if (p_hevc_pps->num_tile_rows_minus1 >=
> +			    ARRAY_SIZE(p_hevc_pps->row_height_minus1))
> +				return -EINVAL;
>   		}
>   
>   		if (p_hevc_pps->flags &