Re: [PATCH] s390: crypto: Return -EFAULT if copy_to_user() fails

[Tony Krowiak]

On 3/1/21 7:08 AM, Wang Qing wrote:
> The copy_to_user() function returns the number of bytes remaining to be
> copied, but we want to return -EFAULT if the copy doesn't complete.
>
> Signed-off-by: Wang Qing <wangqing@xxxxxxxx>
> ---
>   drivers/s390/crypto/vfio_ap_ops.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
> index 41fc2e413..1ffdd41
> --- a/drivers/s390/crypto/vfio_ap_ops.c
> +++ b/drivers/s390/crypto/vfio_ap_ops.c
> @@ -1286,7 +1286,7 @@ static int vfio_ap_mdev_get_device_info(unsigned long arg)
>   	info.num_regions = 0;
>   	info.num_irqs = 0;
>   
> -	return copy_to_user((void __user *)arg, &info, minsz);
> +	return copy_to_user((void __user *)arg, &info, minsz) ? -EFAULT : 0;
>   }

LGTM
Reviewed-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxx>

>   
>   static ssize_t vfio_ap_mdev_ioctl(struct mdev_device *mdev,