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 <[email protected]>
Cc: [email protected]
---
Changes in v2:
- Add Fixes tag and CC stable email address
- Change the title to be more expressive
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;
for (i = 0; i < *nplanes; i++)
if (sizes[i] < q_data->sizeimage[i])
return -EINVAL;
--
2.25.1
On Thu, Aug 10, 2023 at 4:23 PM Wei Chen <[email protected]> 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 <[email protected]>
> Cc: [email protected]
Reviewed-by: Chen-Yu Tsai <[email protected]>
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 <[email protected]>
> Cc: [email protected]
> ---
> 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,
Hi,
Le jeudi 10 août 2023 à 08:23 +0000, Wei Chen a écrit :
> 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 <[email protected]>
> Cc: [email protected]
> ---
> Changes in v2:
> - Add Fixes tag and CC stable email address
> - Change the title to be more expressive
>
> 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;
I don't think the claim really exists. For this driver, when *nplane is set,
it will be:
case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
requested_planes = f->fmt.pix_mp.num_planes;
if (requested_planes == 0 ||
requested_planes > VIDEO_MAX_PLANES)
return -EINVAL;
for (i = 0; i < requested_planes; i++)
requested_sizes[i] =
f->fmt.pix_mp.plane_fmt[i].sizeimage;
break;
Or the value the driver have set it in the previous call with *nplane == 0. So
unless there is a bug, this should not happen, and more importantly, the core
should not let that happen, meaning it should not be driver jobs to validate
this.
my 2 cents,
Nicolas
> for (i = 0; i < *nplanes; i++)
> if (sizes[i] < q_data->sizeimage[i])
> return -EINVAL;
On Thu, Aug 10, 2023 at 12:12:39PM +0300, Eugen Hristev wrote:
> 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 <[email protected]>
> > Cc: [email protected]
> > ---
> > 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
It's easiest if it is added by the submitter, makes the maintainer's job
much easier.
thanks,
greg k-h