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Message-ID: <45d0f538-9769-f4eb-7479-cf676337ff55@collabora.com>
Date:   Thu, 10 Aug 2023 12:12:39 +0300
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Subject: Re: [PATCH v2] media: vcodec: Fix potential array out-of-bounds in
 encoder queue_setup
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To:     Wei Chen <harperchen1110@gmail.com>, tiffany.lin@mediatek.com
Cc:     andrew-ct.chen@mediatek.com, yunfei.dong@mediatek.com,
        mchehab@kernel.org, matthias.bgg@gmail.com,
        angelogioacchino.delregno@collabora.com,
        linux-media@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org, stable@vger.kernel.org
References: <20230810082333.972165-1-harperchen1110@gmail.com>
From:   Eugen Hristev <eugen.hristev@collabora.com>
In-Reply-To: <20230810082333.972165-1-harperchen1110@gmail.com>
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Hi Wei,

On 8/10/23 11:23, Wei Chen wrote:
> variable *nplanes is provided by user via system call argument. The
> possible value of q_data->fmt->num_planes is 1-3, while the value
> of *nplanes can be 1-8. The array access by index i can cause array
> out-of-bounds.
> 
> Fix this bug by checking *nplanes against the array size.
> 
> Fixes: 4e855a6efa54 ("[media] vcodec: mediatek: Add Mediatek V4L2 Video Encoder Driver")
> Signed-off-by: Wei Chen <harperchen1110@gmail.com>
> Cc: stable@vger.kernel.org
> ---
> Changes in v2:
> - Add Fixes tag and CC stable email address
I guess stable needs to be added by the maintainer, not by the submitter

> - Change the title to be more expressive

Subject message should include mediatek I believe, as `media: vcodec:` 
does not reference the mediatek vcodec.

> 
>   drivers/media/platform/mediatek/vcodec/mtk_vcodec_enc.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/media/platform/mediatek/vcodec/mtk_vcodec_enc.c b/drivers/media/platform/mediatek/vcodec/mtk_vcodec_enc.c
> index 9ff439a50f53..9e8817863cb8 100644
> --- a/drivers/media/platform/mediatek/vcodec/mtk_vcodec_enc.c
> +++ b/drivers/media/platform/mediatek/vcodec/mtk_vcodec_enc.c
> @@ -821,6 +821,8 @@ static int vb2ops_venc_queue_setup(struct vb2_queue *vq,
>   		return -EINVAL;
>   
>   	if (*nplanes) {
> +		if (*nplanes != q_data->fmt->num_planes)
> +			return -EINVAL;

Have you run v4l2-compliance on the device to make sure nothing is broken ?

>   		for (i = 0; i < *nplanes; i++)
>   			if (sizes[i] < q_data->sizeimage[i])
>   				return -EINVAL;


Greetings,