From 7ebe183c6d444ef5587d803b64a1f4734b18c564 Mon Sep 17 00:00:00 2001 From: Yuchung Cheng Date: Sun, 24 Mar 2013 10:42:25 +0000 Subject: tcp: undo spurious timeout after SACK reneging On SACK reneging the sender immediately retransmits and forces a timeout but disables Eifel (undo). If the (buggy) receiver does not drop any packet this can trigger a false slow-start retransmit storm driven by the ACKs of the original packets. This can be detected with undo and TCP timestamps. Signed-off-by: Yuchung Cheng Acked-by: Neal Cardwell Signed-off-by: David S. Miller --- net/ipv4/tcp_input.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) (limited to 'net/ipv4') diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 0d9bdacce99f..3bd55bad230a 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -2059,11 +2059,8 @@ void tcp_enter_loss(struct sock *sk, int how) if (tcp_is_reno(tp)) tcp_reset_reno_sack(tp); - if (!how) { - /* Push undo marker, if it was plain RTO and nothing - * was retransmitted. */ - tp->undo_marker = tp->snd_una; - } else { + tp->undo_marker = tp->snd_una; + if (how) { tp->sacked_out = 0; tp->fackets_out = 0; } -- cgit v1.2.3 From 330305cc4a6b0cb75c22fc01b8826f0ad755550f Mon Sep 17 00:00:00 2001 From: Pravin B Shelar Date: Sun, 24 Mar 2013 17:36:29 +0000 Subject: ipv4: Fix ip-header identification for gso packets. ip-header id needs to be incremented even if IP_DF flag is set. This behaviour was changed in commit 490ab08127cebc25e3a26 (IP_GRE: Fix IP-Identification). Following patch fixes it so that identification is always incremented. Reported-by: Cong Wang Signed-off-by: Pravin B Shelar Signed-off-by: David S. Miller --- net/ipv4/af_inet.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'net/ipv4') diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 68f6a94f7661..c929d9c1c4b6 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1333,8 +1333,7 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb, iph->frag_off |= htons(IP_MF); offset += (skb->len - skb->mac_len - iph->ihl * 4); } else { - if (!(iph->frag_off & htons(IP_DF))) - iph->id = htons(id++); + iph->id = htons(id++); } iph->tot_len = htons(skb->len - skb->mac_len); iph->check = 0; -- cgit v1.2.3