diff options
Diffstat (limited to 'net/ipv4/tcp_timer.c')
| -rw-r--r-- | net/ipv4/tcp_timer.c | 17 | 
1 files changed, 13 insertions, 4 deletions
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c index c9c716a483e4..a4730a28b220 100644 --- a/net/ipv4/tcp_timer.c +++ b/net/ipv4/tcp_timer.c @@ -24,9 +24,6 @@  int sysctl_tcp_syn_retries __read_mostly = TCP_SYN_RETRIES;  int sysctl_tcp_synack_retries __read_mostly = TCP_SYNACK_RETRIES; -int sysctl_tcp_keepalive_time __read_mostly = TCP_KEEPALIVE_TIME; -int sysctl_tcp_keepalive_probes __read_mostly = TCP_KEEPALIVE_PROBES; -int sysctl_tcp_keepalive_intvl __read_mostly = TCP_KEEPALIVE_INTVL;  int sysctl_tcp_retries1 __read_mostly = TCP_RETR1;  int sysctl_tcp_retries2 __read_mostly = TCP_RETR2;  int sysctl_tcp_orphan_retries __read_mostly; @@ -168,7 +165,7 @@ static int tcp_write_timeout(struct sock *sk)  			dst_negative_advice(sk);  			if (tp->syn_fastopen || tp->syn_data)  				tcp_fastopen_cache_set(sk, 0, NULL, true, 0); -			if (tp->syn_data) +			if (tp->syn_data && icsk->icsk_retransmits == 1)  				NET_INC_STATS_BH(sock_net(sk),  						 LINUX_MIB_TCPFASTOPENACTIVEFAIL);  		} @@ -176,6 +173,18 @@ static int tcp_write_timeout(struct sock *sk)  		syn_set = true;  	} else {  		if (retransmits_timed_out(sk, 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. +			 */ +			if (tp->syn_data_acked && +			    tp->bytes_acked <= tp->rx_opt.mss_clamp) { +				tcp_fastopen_cache_set(sk, 0, NULL, true, 0); +				if (icsk->icsk_retransmits == sysctl_tcp_retries1) +					NET_INC_STATS_BH(sock_net(sk), +							 LINUX_MIB_TCPFASTOPENACTIVEFAIL); +			}  			/* Black hole detection */  			tcp_mtu_probing(icsk, sk);  | 
