Received-SPF: pass (google.com: domain of linux-kernel+bounces-71495-linux.lists.archive=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) client-ip=139.178.88.99;
Message-ID: <007655fb-d56a-4d6e-a19f-46e418f0a4e5@redhat.com>
Date: Mon, 19 Feb 2024 15:40:07 +0100
Precedence: bulk
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH] [v2] media: atomisp: ssh_css: Fix a null-pointer
 dereference in load_video_binaries
Content-Language: en-US
To: Zhipeng Lu <alexious@zju.edu.cn>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>,
 Sakari Ailus <sakari.ailus@linux.intel.com>,
 Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Kate Hsuan
 <hpa@redhat.com>, Dan Carpenter <error27@gmail.com>,
 Andy Shevchenko <andy.shevchenko@gmail.com>,
 Brent Pappas <bpappas@pappasbrent.com>, Alan Cox <alan@linux.intel.com>,
 linux-media@vger.kernel.org, linux-staging@lists.linux.dev,
 linux-kernel@vger.kernel.org
References: <20240118151303.3828292-1-alexious@zju.edu.cn>
From: Hans de Goede <hdegoede@redhat.com>
In-Reply-To: <20240118151303.3828292-1-alexious@zju.edu.cn>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit

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;
>  		}