diff options
| author | Eric Dumazet <edumazet@google.com> | 2023-10-31 06:19:45 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2023-11-03 09:16:42 +0000 |
| commit | cdbab6236605dc11780779d9af689aea7d58cab1 (patch) | |
| tree | 6ca641ce4706ca88d28d25882ab4af4215e1a483 /net/ipv4/tcp_output.c | |
| parent | 63e201916b27260218e528a2f8758be47f99bbf4 (diff) | |
tcp: fix fastopen code vs usec TS
After blamed commit, TFO client-ack-dropped-then-recovery-ms-timestamps
packetdrill test failed.
David Morley and Neal Cardwell started investigating and Neal pointed
that we had :
tcp_conn_request()
tcp_try_fastopen()
-> tcp_fastopen_create_child
-> child = inet_csk(sk)->icsk_af_ops->syn_recv_sock()
-> tcp_create_openreq_child()
-> copy req_usec_ts from req:
newtp->tcp_usec_ts = treq->req_usec_ts;
// now the new TFO server socket always does usec TS, no matter
// what the route options are...
send_synack()
-> tcp_make_synack()
// disable tcp_rsk(req)->req_usec_ts if route option is not present:
if (tcp_rsk(req)->req_usec_ts < 0)
tcp_rsk(req)->req_usec_ts = dst_tcp_usec_ts(dst);
tcp_conn_request() has the initial dst, we can initialize
tcp_rsk(req)->req_usec_ts there instead of later in send_synack();
This means tcp_rsk(req)->req_usec_ts can be a boolean.
Many thanks to David an Neal for their help.
Fixes: 614e8316aa4c ("tcp: add support for usec resolution in TCP TS values")
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202310302216.f79d78bc-oliver.sang@intel.com
Suggested-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Morley <morleyd@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp_output.c')
| -rw-r--r-- | net/ipv4/tcp_output.c | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index f558c054cf6e..0d8dd5b7e2e5 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -3693,8 +3693,6 @@ struct sk_buff *tcp_make_synack(const struct sock *sk, struct dst_entry *dst, mss = tcp_mss_clamp(tp, dst_metric_advmss(dst)); memset(&opts, 0, sizeof(opts)); - if (tcp_rsk(req)->req_usec_ts < 0) - tcp_rsk(req)->req_usec_ts = dst_tcp_usec_ts(dst); now = tcp_clock_ns(); #ifdef CONFIG_SYN_COOKIES if (unlikely(synack_type == TCP_SYNACK_COOKIE && ireq->tstamp_ok)) |