The stated intent of the original commit is to is to "return the timestamp corresponding to the highest sequence number data returned." The current implementation returns the timestamp for the last byte of the last fully read skb, which is not necessarily the last byte in the recv buffer. This patch converts behavior to the original definition, and to the behavior of the previous draft versions of commit 98aaa913b4ed ("tcp: Extend SOF_TIMESTAMPING_RX_SOFTWARE to TCP recvmsg") which also match this behavior.
Co-developed-by: Iris Liu <i...@onechronos.com> Signed-off-by: Iris Liu <i...@onechronos.com> Signed-off-by: Kelly Littlepage <ke...@onechronos.com> --- Thanks and credit to Willem de Bruijn for the revised commit language net/ipv4/tcp.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 6d87de434377..e72bd651d21a 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2154,13 +2154,15 @@ int tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock, tp->urg_data = 0; tcp_fast_path_check(sk); } - if (used + offset < skb->len) - continue; if (TCP_SKB_CB(skb)->has_rxtstamp) { tcp_update_recv_tstamps(skb, &tss); cmsg_flags |= 2; } + + if (used + offset < skb->len) + continue; + if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) goto found_fin_ok; if (!(flags & MSG_PEEK)) -- 2.26.2 -- This email and any attachments thereto may contain private, confidential, and privileged material for the sole use of the intended recipient. If you are not the intended recipient or otherwise believe that you have received this message in error, please notify the sender immediately and delete the original. Any review, copying, or distribution of this email (or any attachments thereto) by others is strictly prohibited. If this message was misdirected, OCX Group Inc. does not waive any confidentiality or privilege.