Re: [PATCH] PCI: dwc: Fix signedness bug in fault injection test code

[Hans Zhang]

On 5/12/26 18:17, Dan Carpenter wrote:
> The kstrtou32() function returns negative error code or zero on success.
> However, in this case "val" is a u32 and the function returns signed
> longs so negative error codes from kstrtou32() are returned as high
> positive values.
>
> Store the error code in an int instead.
>
> Fixes: d20ee8e2dbd6 ("PCI: dwc: Add debugfs based Error Injection support for DWC")
> Signed-off-by: Dan Carpenter <error27@xxxxxxxxx>

Reviewed-by: Hans Zhang <18255117159@xxxxxxx>

> ---
>   drivers/pci/controller/dwc/pcie-designware-debugfs.c | 7 ++++---
>   1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-designware-debugfs.c b/drivers/pci/controller/dwc/pcie-designware-debugfs.c
> index 945f8f9b6d0e..a6737bdc46ac 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-debugfs.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-debugfs.c
> @@ -305,6 +305,7 @@ static ssize_t err_inj_write(struct file *file, const char __user *buf,
>   	u32 val, counter, vc_num, err_group, type_mask;
>   	int val_diff = 0;
>   	char *kern_buf;
> +	int ret;
>   
>   	err_group = err_inj_list[pdata->idx].err_inj_group;
>   	type_mask = err_inj_type_mask[err_group];
> @@ -326,10 +327,10 @@ static ssize_t err_inj_write(struct file *file, const char __user *buf,
>   			return -EINVAL;
>   		}
>   	} else {
> -		val = kstrtou32(kern_buf, 0, &counter);
> -		if (val) {
> +		ret = kstrtou32(kern_buf, 0, &counter);
> +		if (ret) {
>   			kfree(kern_buf);
> -			return val;
> +			return ret;
>   		}
>   	}
>