Re: [PATCH] samples/vfio-mdev: don't return zero on failure paths in mtty_dev_init()

[Kirti Wankhede]

Dan Carpenter had sent similar change earlier.
https://www.spinics.net/lists/kvm/msg141470.html

Alex,
Did you pull that change in your tree?

Thanks,
Kirti

On 12/31/2016 4:10 AM, Alexey Khoroshilov wrote:
> If class_create() or mdev_register_device() fail, mtty_dev_init()
> breaks off initialization, deallocates all resources, but returns zero.
> 
> The patch adds proper error code return values.
> 
> Found by Linux Driver Verification project (linuxtesting.org).
> 
> Signed-off-by: Alexey Khoroshilov <khoroshilov@xxxxxxxxx>
> ---
>  samples/vfio-mdev/mtty.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
> index 6b633a4ea333..e9c52e1f97a6 100644
> --- a/samples/vfio-mdev/mtty.c
> +++ b/samples/vfio-mdev/mtty.c
> @@ -1446,6 +1446,7 @@ static int __init mtty_dev_init(void)
>  	mtty_dev.vd_class = class_create(THIS_MODULE, MTTY_CLASS_NAME);
>  
>  	if (IS_ERR(mtty_dev.vd_class)) {
> +		ret = PTR_ERR(mtty_dev.vd_class);
>  		pr_err("Error: failed to register mtty_dev class\n");
>  		goto failed1;
>  	}
> @@ -1458,7 +1459,8 @@ static int __init mtty_dev_init(void)
>  	if (ret)
>  		goto failed2;
>  
> -	if (mdev_register_device(&mtty_dev.dev, &mdev_fops) != 0)
> +	ret = mdev_register_device(&mtty_dev.dev, &mdev_fops);
> +	if (ret)
>  		goto failed3;
>  
>  	mutex_init(&mdev_list_lock);
> @@ -1467,11 +1469,9 @@ static int __init mtty_dev_init(void)
>  	goto all_done;
>  
>  failed3:
> -
>  	device_unregister(&mtty_dev.dev);
>  failed2:
>  	class_destroy(mtty_dev.vd_class);
> -
>  failed1:
>  	cdev_del(&mtty_dev.vd_cdev);
>  	unregister_chrdev_region(mtty_dev.vd_devt, MINORMASK);
>