Re: [RFC PATCH v2 1/2] misc: pci_endpoint_test: Aggregate params checking for xfer

[Greg Kroah-Hartman]

On Tue, Sep 06, 2022 at 07:15:54PM +0900, Shunsuke Mie wrote:
> Each transfer test functions have same parameter checking code. This patch
> unites those to an introduced function.
> 
> Signed-off-by: Shunsuke Mie <mie@xxxxxxxxxx>
> ---
> Changes in v2:
> * New patch
> ---
> ---
>  drivers/misc/pci_endpoint_test.c | 35 ++++++++++++++++++++++++++------
>  1 file changed, 29 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/misc/pci_endpoint_test.c b/drivers/misc/pci_endpoint_test.c
> index 8f786a225dcf..3bd9f135cdac 100644
> --- a/drivers/misc/pci_endpoint_test.c
> +++ b/drivers/misc/pci_endpoint_test.c
> @@ -332,6 +332,17 @@ static bool pci_endpoint_test_msi_irq(struct pci_endpoint_test *test,
>  	return false;
>  }
>  
> +static int pci_endpoint_test_validate_xfer_params(struct device *dev,
> +		struct pci_endpoint_test_xfer_param *param, size_t alignment)
> +{
> +	if (param->size > SIZE_MAX - alignment) {
> +		dev_err(dev, "Maximum transfer data size exceeded\n");
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
>  static bool pci_endpoint_test_copy(struct pci_endpoint_test *test,
>  				   unsigned long arg)
>  {
> @@ -363,9 +374,13 @@ static bool pci_endpoint_test_copy(struct pci_endpoint_test *test,
>  		return false;
>  	}
>  
> +	err = pci_endpoint_test_validate_xfer_params(dev, &param, alignment);
> +	if (err) {
> +		dev_err(dev, "Invalid parameter\n");

Also, you just printed 2 errors for the same error.  Not needed.