Subject: Re: [PATCH v2 1/2] PTP: introduce new versions of IOCTLs

From: Richard Cochran <[email-masked]>
Date: Thu, 29 Aug 2019 10:21:13 -0700

> @@ -139,11 +141,24 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
>  		break;
>  
>  	case PTP_EXTTS_REQUEST:
> +	case PTP_EXTTS_REQUEST2:
> +		memset(&req, 0, sizeof(req));
> +
>  		if (copy_from_user(&req.extts, (void __user *)arg,
>  				   sizeof(req.extts))) {
>  			err = -EFAULT;
>  			break;
>  		}
> +		if ((req.extts.flags || req.extts.rsv[0] || req.extts.rsv[1])
> +			&& cmd == PTP_EXTTS_REQUEST2) {
> +			err = -EINVAL;
> +			break;
> +		} else if (cmd == PTP_EXTTS_REQUEST) {
> +			req.extts.flags = 0;

This still isn't quite right.  Sorry that was my fault.

The req.extts.flags can be (PTP_ENABLE_FEATURE | PTP_RISING_EDGE |
PTP_FALLING_EDGE), and ENABLE is used immediately below in this case.

Please #define those bits into a valid mask, and then:

- for PTP_EXTTS_REQUEST2 check that ~mask is zero, and
- for PTP_EXTTS_REQUEST clear the ~mask bits for the drivers. 

Thanks again for cleaning this up!

Richard

> +			req.extts.rsv[0] = 0;
> +			req.extts.rsv[1] = 0;
> +		}
> +			
>  		if (req.extts.index >= ops->n_ext_ts) {
>  			err = -EINVAL;
>  			break;