path: root/net/ipv4/tcp_timer.c
diff options
authorWei Wang <weiwan@google.com>2017-04-20 14:45:48 -0700
committerDavid S. Miller <davem@davemloft.net>2017-04-24 14:27:17 -0400
commit59450f8d83cb6743178c7996a6c6fc78ff3e6db9 (patch)
tree258bd7edb6ba1acf0241d1276fd58b1c6be1dcb8 /net/ipv4/tcp_timer.c
parentnet/tcp_fastopen: Add snmp counter for blackhole detection (diff)
net/tcp_fastopen: Remove mss check in tcp_write_timeout()
Christoph Paasch from Apple found another firewall issue for TFO: After successful 3WHS using TFO, server and client starts to exchange data. Afterwards, a 10s idle time occurs on this connection. After that, firewall starts to drop every packet on this connection. The fix for this issue is to extend existing firewall blackhole detection logic in tcp_write_timeout() by removing the mss check. Signed-off-by: Wei Wang <weiwan@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to '')
1 files changed, 3 insertions, 4 deletions
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index b2ab411c6d37..14672543cf0b 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -201,11 +201,10 @@ static int tcp_write_timeout(struct sock *sk)
if (retransmits_timed_out(sk, net->ipv4.sysctl_tcp_retries1, 0, 0)) {
/* Some middle-boxes may black-hole Fast Open _after_
* the handshake. Therefore we conservatively disable
- * Fast Open on this path on recurring timeouts with
- * few or zero bytes acked after Fast Open.
+ * Fast Open on this path on recurring timeouts after
+ * successful Fast Open.
- if (tp->syn_data_acked &&
- tp->bytes_acked <= tp->rx_opt.mss_clamp) {
+ if (tp->syn_data_acked) {
tcp_fastopen_cache_set(sk, 0, NULL, true, 0);
if (icsk->icsk_retransmits == net->ipv4.sysctl_tcp_retries1)