From 600a2d1311b0c73ece60fbb3eda46372f6c7ceaa Mon Sep 17 00:00:00 2001 From: Yuchung Cheng Date: Fri, 24 Sep 2010 13:22:06 +0000 Subject: [PATCH] tcp: fix TSO FACK loss marking in tcp_mark_head_lost MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit When TCP uses FACK algorithm to mark lost packets in tcp_mark_head_lost(), if the number of packets in the (TSO) skb is greater than the number of packets that should be marked lost, TCP incorrectly exits the loop and marks no packets lost in the skb. This underestimates tp->lost_out and affects the recovery/retransmission. This patch fargments the skb and marks the correct amount of packets lost. Signed-off-by: Yuchung Cheng Acked-by: Ilpo Järvinen Signed-off-by: David S. Miller --- net/ipv4/tcp_input.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 149e79ac28918..b55f60f6fcbe9 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -2545,7 +2545,8 @@ static void tcp_mark_head_lost(struct sock *sk, int packets) cnt += tcp_skb_pcount(skb); if (cnt > packets) { - if (tcp_is_sack(tp) || (oldcnt >= packets)) + if ((tcp_is_sack(tp) && !tcp_is_fack(tp)) || + (oldcnt >= packets)) break; mss = skb_shinfo(skb)->gso_size; -- 2.39.5