From: Kelly Littlepage <ke...@onechronos.com> 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.
Fixes: 98aaa913b4ed ("tcp: Extend SOF_TIMESTAMPING_RX_SOFTWARE to TCP recvmsg") Co-developed-by: Iris Liu <i...@onechronos.com> Signed-off-by: Iris Liu <i...@onechronos.com> Signed-off-by: Kelly Littlepage <ke...@onechronos.com> Signed-off-by: Eric Dumazet <eduma...@google.com> Acked-by: Soheil Hassas Yeganeh <soh...@google.com> Acked-by: Willem de Bruijn <will...@google.com> --- Sending from an alternative email given the compliance footer that's unavoidably attached to all emails from my primary account. The patch itself is unchanged. 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