From: Octavian Purdila Date: Wed, 25 Jun 2014 14:09:51 +0000 (+0300) Subject: tcp: tcp_v[46]_conn_request: fix snt_synack initialization X-Git-Tag: firefly_0821_release~176^2~3474^2~253^2~11 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=aa27fc501;p=firefly-linux-kernel-4.4.55.git tcp: tcp_v[46]_conn_request: fix snt_synack initialization Commit 016818d07 (tcp: TCP Fast Open Server - take SYNACK RTT after completing 3WHS) changes the code to only take a snt_synack timestamp when a SYNACK transmit or retransmit succeeds. This behaviour is later broken by commit 843f4a55e (tcp: use tcp_v4_send_synack on first SYN-ACK), as snt_synack is now updated even if tcp_v4_send_synack fails. Also, commit 3a19ce0ee (tcp: IPv6 support for fastopen server) misses the required IPv6 updates for 016818d07. This patch makes sure that snt_synack is updated only when the SYNACK trasnmit/retransmit succeeds, for both IPv4 and IPv6. Cc: Cardwell Cc: Daniel Lee Cc: Yuchung Cheng Signed-off-by: Octavian Purdila Signed-off-by: David S. Miller --- diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 180336d47df6..145f6402c560 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1370,7 +1370,6 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) goto drop_and_free; tcp_rsk(req)->snt_isn = isn; - tcp_rsk(req)->snt_synack = tcp_time_stamp; tcp_openreq_init_rwin(req, sk, dst); fastopen = !want_cookie && tcp_try_fastopen(sk, skb, req, &foc, dst); @@ -1380,7 +1379,6 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) if (err || want_cookie) goto drop_and_free; - tcp_rsk(req)->snt_synack = tcp_time_stamp; tcp_rsk(req)->listener = NULL; inet_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT); } diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 08ae3da0db4a..a962455471ba 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -497,6 +497,8 @@ static int tcp_v6_send_synack(struct sock *sk, struct dst_entry *dst, skb_set_queue_mapping(skb, queue_mapping); err = ip6_xmit(sk, skb, fl6, np->opt, np->tclass); err = net_xmit_eval(err); + if (!tcp_rsk(req)->snt_synack && !err) + tcp_rsk(req)->snt_synack = tcp_time_stamp; } done: @@ -1100,7 +1102,6 @@ have_isn: goto drop_and_free; tcp_rsk(req)->snt_isn = isn; - tcp_rsk(req)->snt_synack = tcp_time_stamp; tcp_openreq_init_rwin(req, sk, dst); fastopen = !want_cookie && tcp_try_fastopen(sk, skb, req, &foc, dst);