Re: [PATCH 1/4] uacce: fix for cdev memory leak

[Greg KH <gregkh@linuxfoundation.org>]

On Fri, Aug 22, 2025 at 06:39:01PM +0800, Chenghai Huang wrote:
> From: Wenkai Lin <linwenkai6@hisilicon.com>
> 
> If adding uacce cdev to the system fails, it could be due to two
> reasons: either the device's devt exists when the failure occurs,
> or the device_add operation fails. In the latter case, cdev_del
> will be executed, but in the former case, it will not, leading to a
> resource leak. Therefore, it is necessary to perform the cdev_del
> action during abnormal exit.
> 
> Fixes: 015d239ac014 ("uacce: add uacce driver")
> Signed-off-by: Wenkai Lin <linwenkai6@hisilicon.com>
> Signed-off-by: Chenghai Huang <huangchenghai2@huawei.com>
> ---
>  drivers/misc/uacce/uacce.c | 11 ++++++++++-
>  1 file changed, 10 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/misc/uacce/uacce.c b/drivers/misc/uacce/uacce.c
> index 42e7d2a2a90c..3604f722ed60 100644
> --- a/drivers/misc/uacce/uacce.c
> +++ b/drivers/misc/uacce/uacce.c
> @@ -519,6 +519,8 @@ EXPORT_SYMBOL_GPL(uacce_alloc);
>   */
>  int uacce_register(struct uacce_device *uacce)
>  {
> +	int ret;
> +
>  	if (!uacce)
>  		return -ENODEV;
>  
> @@ -529,7 +531,14 @@ int uacce_register(struct uacce_device *uacce)
>  	uacce->cdev->ops = &uacce_fops;
>  	uacce->cdev->owner = THIS_MODULE;
>  
> -	return cdev_device_add(uacce->cdev, &uacce->dev);
> +	ret = cdev_device_add(uacce->cdev, &uacce->dev);
> +	if (ret) {
> +		cdev_del(uacce->cdev);
> +		uacce->cdev = NULL;
> +		return ret;
> +	}
> +
> +	return 0;
>  }
>  EXPORT_SYMBOL_GPL(uacce_register);
>  
> -- 
> 2.33.0
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
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