Re: [RFC v2 net-next 01/10] net: Add a new socket option for a future transmit time.

[Richard Cochran]

On Wed, Jan 17, 2018 at 03:06:12PM -0800, Jesus Sanchez-Palencia wrote:
> @@ -2130,6 +2137,15 @@ int __sock_cmsg_send(struct sock *sk, struct msghdr 
> *msg, struct cmsghdr *cmsg,
>               sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
>               sockc->tsflags |= tsflags;
>               break;
> +     case SO_TXTIME:
> +             if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
> +                     return -EPERM;
> +             if (!sock_flag(sk, SOCK_TXTIME))
> +                     return -EINVAL;
> +             if (cmsg->cmsg_len != CMSG_LEN(sizeof(ktime_t)))
> +                     return -EINVAL;
> +             sockc->transmit_time = *(ktime_t *)CMSG_DATA(cmsg);

As pointed out in the first series' review:

  No guarantee the CMSG is properly aligned on arches that might trap
  on unaligned access.

Thanks,
Richard