Hi,

While I was tracing why TX_TIMESTAMP won't work with RAW socket and Non-privileged ICMP socket, I found that both raw.c and ping.c call ip_append_data with transhdrlen set to 0, and in ip_append_data, there are timestamp specific 

924                                 else
925                                         /* only the initial fragment is
926                                            time stamped */
927                                         cork->tx_flags = 0;

To my understanding in ping.c transhdrlen should be set to sizeof(struct icmphdr) just like what icmp.c did.

And for RAW socket, since there are no concept of fragmentation, should we check the protocol and only set cork->tx_flags = 0 when the socket_type != SOCK_RAW