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Date:   Thu, 4 May 2023 16:54:20 +0200
From:   Johan Hovold <johan@kernel.org>
To:     Dongliang Mu <dzm91@hust.edu.cn>
Cc:     Alex Elder <elder@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jacopo Mondi <jacopo.mondi@linaro.org>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Greg Kroah-Hartman <gregkh@google.com>,
        greybus-dev@lists.linaro.org, linux-staging@lists.linux.dev,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] drivers: staging: greybus: fix GPF issue in
 gb_camera_capture
Message-ID: <ZFPHHImqiVRRV5Cd@hovoldconsulting.com>
References: <20230504135841.1566958-1-dzm91@hust.edu.cn>
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On Thu, May 04, 2023 at 09:58:41PM +0800, Dongliang Mu wrote:
> In gb_camera_capture(), it does not check the value of settings
> before dereferencing it. And gb_camera_debugfs_capture calls
> gb_camera_capture with the 6th parameter settings as NULL.

Looks like you just broke gb_camera_debugfs_capture() which relies on
passing NULL as settings.

> Fix this by checking the value of setting at the starting of
> gb_camera_capture.
> 
> Fixes: 3265edaf0d70 ("greybus: Add driver for the camera class protocol")
> Signed-off-by: Dongliang Mu <dzm91@hust.edu.cn>
> ---
>  drivers/staging/greybus/camera.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/staging/greybus/camera.c b/drivers/staging/greybus/camera.c
> index cdbb42cd413b..5a4b26e7f645 100644
> --- a/drivers/staging/greybus/camera.c
> +++ b/drivers/staging/greybus/camera.c
> @@ -659,7 +659,7 @@ static int gb_camera_capture(struct gb_camera *gcam, u32 request_id,
>  	size_t req_size;
>  	int ret;
>  
> -	if (settings_size > GB_CAMERA_MAX_SETTINGS_SIZE)
> +	if (settings_size > GB_CAMERA_MAX_SETTINGS_SIZE || !settings)
>  		return -EINVAL;
>  
>  	req_size = sizeof(*req) + settings_size;

Johan