[PATCH] [v2] media: atomisp: ssh_css: Fix a null-pointer dereference in load_video_binaries

[PATCH] [v2] media: atomisp: ssh_css: Fix a null-pointer dereference in load_video_binaries

[Zhipeng Lu]

The allocation failure of mycs->yuv_scaler_binary in load_video_binaries
is followed with a dereference of mycs->yuv_scaler_binary after the
following call chain:

sh_css_pipe_load_binaries
  |-> load_video_binaries (mycs->yuv_scaler_binary == NULL)
  |
  |-> sh_css_pipe_unload_binaries
        |-> unload_video_binaries

In unload_video_binaries, it calls to ia_css_binary_unload with argument
&pipe->pipe_settings.video.yuv_scaler_binary[i], which refers to the
same memory slot as mycs->yuv_scaler_binary. Thus, a null-pointer
dereference is triggered.

Fixes: a49d25364dfb ("staging/atomisp: Add support for the Intel IPU v2")
Signed-off-by: Zhipeng Lu <alexious@zju.edu.cn>
---
Changelog:

v2: change fix approach to set mycs->num_yuv_scaler = 0 in
load_video_binaries. Change the fix tag to correct commit.
---
 drivers/staging/media/atomisp/pci/sh_css.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/staging/media/atomisp/pci/sh_css.c b/drivers/staging/media/atomisp/pci/sh_css.c
index f35c90809414..638f08b3f21b 100644
--- a/drivers/staging/media/atomisp/pci/sh_css.c
+++ b/drivers/staging/media/atomisp/pci/sh_css.c
@@ -4719,6 +4719,7 @@ static int load_video_binaries(struct ia_css_pipe *pipe)
 						  sizeof(struct ia_css_binary),
 						  GFP_KERNEL);
 		if (!mycs->yuv_scaler_binary) {
+			mycs->num_yuv_scaler = 0;
 			err = -ENOMEM;
 			return err;
 		}
-- 
2.34.1

Re: [PATCH] [v2] media: atomisp: ssh_css: Fix a null-pointer dereference in load_video_binaries

[Andy Shevchenko]

On Thu, Jan 18, 2024 at 5:13 PM Zhipeng Lu <alexious@zju.edu.cn> wrote:
>
> The allocation failure of mycs->yuv_scaler_binary in load_video_binaries
> is followed with a dereference of mycs->yuv_scaler_binary after the
> following call chain:
>
> sh_css_pipe_load_binaries
>   |-> load_video_binaries (mycs->yuv_scaler_binary == NULL)
>   |
>   |-> sh_css_pipe_unload_binaries
>         |-> unload_video_binaries
>
> In unload_video_binaries, it calls to ia_css_binary_unload with argument
> &pipe->pipe_settings.video.yuv_scaler_binary[i], which refers to the
> same memory slot as mycs->yuv_scaler_binary. Thus, a null-pointer
> dereference is triggered.

Good for me now, thank you.
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

P.S. If needed, or Hans can do it, the references to the functions can
be amended in the commit message as we use the 'func()' format (w/o
quotes).

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH] [v2] media: atomisp: ssh_css: Fix a null-pointer dereference in load_video_binaries

[Hans de Goede]

Hi,

On 1/18/24 16:13, Zhipeng Lu wrote:
> The allocation failure of mycs->yuv_scaler_binary in load_video_binaries
> is followed with a dereference of mycs->yuv_scaler_binary after the
> following call chain:
> 
> sh_css_pipe_load_binaries
>   |-> load_video_binaries (mycs->yuv_scaler_binary == NULL)
>   |
>   |-> sh_css_pipe_unload_binaries
>         |-> unload_video_binaries
> 
> In unload_video_binaries, it calls to ia_css_binary_unload with argument
> &pipe->pipe_settings.video.yuv_scaler_binary[i], which refers to the
> same memory slot as mycs->yuv_scaler_binary. Thus, a null-pointer
> dereference is triggered.
> 
> Fixes: a49d25364dfb ("staging/atomisp: Add support for the Intel IPU v2")
> Signed-off-by: Zhipeng Lu <alexious@zju.edu.cn>
> ---
> Changelog:
> 
> v2: change fix approach to set mycs->num_yuv_scaler = 0 in
> load_video_binaries. Change the fix tag to correct commit.

Thank you for you patch.

I have applied this patch to my media-atomip branch:
https://git.kernel.org/pub/scm/linux/kernel/git/hansg/linux.git/log/?h=media-atomisp

and I will include this in my next media-atomisp
pull-request to Mauro.

Regards,

Hans


> ---
>  drivers/staging/media/atomisp/pci/sh_css.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/staging/media/atomisp/pci/sh_css.c b/drivers/staging/media/atomisp/pci/sh_css.c
> index f35c90809414..638f08b3f21b 100644
> --- a/drivers/staging/media/atomisp/pci/sh_css.c
> +++ b/drivers/staging/media/atomisp/pci/sh_css.c
> @@ -4719,6 +4719,7 @@ static int load_video_binaries(struct ia_css_pipe *pipe)
>  						  sizeof(struct ia_css_binary),
>  						  GFP_KERNEL);
>  		if (!mycs->yuv_scaler_binary) {
> +			mycs->num_yuv_scaler = 0;
>  			err = -ENOMEM;
>  			return err;
>  		}