diff options
authorYuchung Cheng <ycheng@google.com>2019-01-16 15:05:31 -0800
committerDavid S. Miller <davem@davemloft.net>2019-01-17 15:12:26 -0800
commitc7d13c8faa74f4e8ef191f88a252cefab6805b38 (patch)
parenttcp: always set retrans_stamp on recovery (diff)
tcp: properly track retry time on passive Fast Open
This patch addresses a corner issue on timeout behavior of a passive Fast Open socket. A passive Fast Open server may write and close the socket when it is re-trying SYN-ACK to complete the handshake. After the handshake is completely, the server does not properly stamp the recovery start time (tp->retrans_stamp is 0), and the socket may abort immediately on the very first FIN timeout, instead of retying until it passes the system or user specified limit. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1 files changed, 3 insertions, 0 deletions
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index 1e61f0bd6e24..074de38bafbd 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -378,6 +378,7 @@ static void tcp_fastopen_synack_timer(struct sock *sk)
struct inet_connection_sock *icsk = inet_csk(sk);
int max_retries = icsk->icsk_syn_retries ? :
sock_net(sk)->ipv4.sysctl_tcp_synack_retries + 1; /* add one more retry for fastopen */
+ struct tcp_sock *tp = tcp_sk(sk);
struct request_sock *req;
req = tcp_sk(sk)->fastopen_rsk;
@@ -395,6 +396,8 @@ static void tcp_fastopen_synack_timer(struct sock *sk)
inet_rtx_syn_ack(sk, req);
+ if (!tp->retrans_stamp)
+ tp->retrans_stamp = tcp_time_stamp(tp);
inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
TCP_TIMEOUT_INIT << req->num_timeout, TCP_RTO_MAX);