Subject: Re: [PATCH net] ptp: Return -EINVAL on ptp_clock_register if required ops are NULL

From: Vadim Fedorenko <[email-masked]>
Date: Tue, 4 Nov 2025 11:31:51 +0000

On 30/10/2025 18:08, Tim Hostetler wrote:
> ptp_clock should never be registered unless it stubs one of gettimex64()
> or gettime64() and settime64(). WARN_ON_ONCE and error out if either set
> of function pointers is null.
> 
> Cc: [email-masked]
> Fixes: d7d38f5bd7be ("ptp: use the 64 bit get/set time methods for the posix clock.")
> Suggested-by: Kuniyuki Iwashima <[email-masked]>
> Reviewed-by: Kuniyuki Iwashima <[email-masked]>
> Reviewed-by: Harshitha Ramamurthy <[email-masked]>
> Signed-off-by: Tim Hostetler <[email-masked]>
> ---
>   drivers/ptp/ptp_clock.c | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
> index ef020599b771..0bc79076771b 100644
> --- a/drivers/ptp/ptp_clock.c
> +++ b/drivers/ptp/ptp_clock.c
> @@ -325,6 +325,10 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
>   	if (info->n_alarm > PTP_MAX_ALARMS)
>   		return ERR_PTR(-EINVAL);
>   
> +	if (WARN_ON_ONCE((!info->gettimex64 && !info->gettime64) ||
> +			 !info->settime64))
> +		return ERR_PTR(-EINVAL);
> +
>   	/* Initialize a clock structure. */
>   	ptp = kzalloc(sizeof(struct ptp_clock), GFP_KERNEL);
>   	if (!ptp) {

The patch itself LGTM, but I believe it should be targeted to net-next,
as it doesn't actually fix any problem with GVE patches landed net tree
already.

Reviewed-by: Vadim Fedorenko <[email-masked]>