2021-03-24 02:29:13

by Colin King

Subject: [PATCH][next] media: imx-jpeg: Pass the v4l2_jpeg_header header argument by reference

From: Colin Ian King <[email protected]>

Currently the header argument is being passed by value, so a copy of 256
byte structure on the stack is potentially occurring. Fix this by passing
by reference to avoid any large stack copies.

Addresses-Coverity: ("Big parameter passed by value")
Fixes: 2db16c6ed72c ("media: imx-jpeg: Add V4L2 driver for i.MX8 JPEG Encoder/Decoder")
Signed-off-by: Colin Ian King <[email protected]>
---
drivers/media/platform/imx-jpeg/mxc-jpeg.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/media/platform/imx-jpeg/mxc-jpeg.c b/drivers/media/platform/imx-jpeg/mxc-jpeg.c
index adb1715c75d7..f13a8efc35ad 100644
--- a/drivers/media/platform/imx-jpeg/mxc-jpeg.c
+++ b/drivers/media/platform/imx-jpeg/mxc-jpeg.c
@@ -1114,21 +1114,21 @@ static int mxc_jpeg_valid_comp_id(struct device *dev,
}

static u32 mxc_jpeg_get_image_format(struct device *dev,
- const struct v4l2_jpeg_header header)
+ const struct v4l2_jpeg_header *header)
{
int i;
u32 fourcc = 0;

for (i = 0; i < MXC_JPEG_NUM_FORMATS; i++)
- if (mxc_formats[i].subsampling == header.frame.subsampling &&
- mxc_formats[i].nc == header.frame.num_components) {
+ if (mxc_formats[i].subsampling == header->frame.subsampling &&
+ mxc_formats[i].nc == header->frame.num_components) {
fourcc = mxc_formats[i].fourcc;
break;
}
if (fourcc == 0) {
dev_err(dev, "Could not identify image format nc=%d, subsampling=%d\n",
- header.frame.num_components,
- header.frame.subsampling);
+ header->frame.num_components,
+ header->frame.subsampling);
return fourcc;
}
/*
@@ -1137,7 +1137,7 @@ static u32 mxc_jpeg_get_image_format(struct device *dev,
* ITU-T T.872 chapter 6.5.3 APP14 marker segment for colour encoding
*/
if (fourcc == V4L2_PIX_FMT_YUV24 || fourcc == V4L2_PIX_FMT_RGB24) {
- if (header.app14_tf == V4L2_JPEG_APP14_TF_CMYK_RGB)
+ if (header->app14_tf == V4L2_JPEG_APP14_TF_CMYK_RGB)
fourcc = V4L2_PIX_FMT_RGB24;
else
fourcc = V4L2_PIX_FMT_YUV24;
@@ -1258,7 +1258,7 @@ static int mxc_jpeg_parse(struct mxc_jpeg_ctx *ctx,
if (!mxc_jpeg_valid_comp_id(dev, psof, psos))
dev_warn(dev, "JPEG component ids should be 0-3 or 1-4");

- fourcc = mxc_jpeg_get_image_format(dev, header);
+ fourcc = mxc_jpeg_get_image_format(dev, &header);
if (fourcc == 0)
return -EINVAL;

--
2.30.2

2021-03-27 14:34:40

by Mirela Rabulea

Subject: Re: [EXT] [PATCH][next] media: imx-jpeg: Pass the v4l2_jpeg_header header argument by reference

Hi,

On Tue, 2021-03-23 at 14:24 +0000, Colin King wrote:
>
> From: Colin Ian King <[email protected]>
>
> Currently the header argument is being passed by value, so a copy of
> 256
> byte structure on the stack is potentially occurring. Fix this by
> passing
> by reference to avoid any large stack copies.
>
> Addresses-Coverity: ("Big parameter passed by value")
> Fixes: 2db16c6ed72c ("media: imx-jpeg: Add V4L2 driver for i.MX8 JPEG
> Encoder/Decoder")
> Signed-off-by: Colin Ian King <[email protected]>
> ---
> drivers/media/platform/imx-jpeg/mxc-jpeg.c | 14 +++++++-------
> 1 file changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/media/platform/imx-jpeg/mxc-jpeg.c
> b/drivers/media/platform/imx-jpeg/mxc-jpeg.c
> index adb1715c75d7..f13a8efc35ad 100644
> --- a/drivers/media/platform/imx-jpeg/mxc-jpeg.c
> +++ b/drivers/media/platform/imx-jpeg/mxc-jpeg.c
> @@ -1114,21 +1114,21 @@ static int mxc_jpeg_valid_comp_id(struct
> device *dev,
> }
>
> static u32 mxc_jpeg_get_image_format(struct device *dev,
> - const struct v4l2_jpeg_header
> header)
> + const struct v4l2_jpeg_header
> *header)
> {
> int i;
> u32 fourcc = 0;
>
> for (i = 0; i < MXC_JPEG_NUM_FORMATS; i++)
> - if (mxc_formats[i].subsampling ==
> header.frame.subsampling &&
> - mxc_formats[i].nc == header.frame.num_components)
> {
> + if (mxc_formats[i].subsampling == header-
> >frame.subsampling &&
> + mxc_formats[i].nc == header-
> >frame.num_components) {
> fourcc = mxc_formats[i].fourcc;
> break;
> }
> if (fourcc == 0) {
> dev_err(dev, "Could not identify image format nc=%d,
> subsampling=%d\n",
> - header.frame.num_components,
> - header.frame.subsampling);
> + header->frame.num_components,
> + header->frame.subsampling);
> return fourcc;
> }
> /*
> @@ -1137,7 +1137,7 @@ static u32 mxc_jpeg_get_image_format(struct
> device *dev,
> * ITU-T T.872 chapter 6.5.3 APP14 marker segment for colour
> encoding
> */
> if (fourcc == V4L2_PIX_FMT_YUV24 || fourcc ==
> V4L2_PIX_FMT_RGB24) {
> - if (header.app14_tf == V4L2_JPEG_APP14_TF_CMYK_RGB)
> + if (header->app14_tf == V4L2_JPEG_APP14_TF_CMYK_RGB)
> fourcc = V4L2_PIX_FMT_RGB24;
> else
> fourcc = V4L2_PIX_FMT_YUV24;
> @@ -1258,7 +1258,7 @@ static int mxc_jpeg_parse(struct mxc_jpeg_ctx
> *ctx,
> if (!mxc_jpeg_valid_comp_id(dev, psof, psos))
> dev_warn(dev, "JPEG component ids should be 0-3 or 1-
> 4");
>
> - fourcc = mxc_jpeg_get_image_format(dev, header);
> + fourcc = mxc_jpeg_get_image_format(dev, &header);
> if (fourcc == 0)
> return -EINVAL;
>
> --
> 2.30.2
>
Thanks for the patch.

Reviewed-by: Mirela Rabulea <[email protected]>

Regards,
Mirela