From 9ec06ff57a9badef3b6b019f35efc6b21fc27d03 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ilpo=20J=C3=A4rvinen?= Date: Sun, 1 Mar 2009 00:21:36 -0800 Subject: [PATCH] tcp: fix retrans_out leaks MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit There's conflicting assumptions in shifting, the caller assumes that dupsack results in S'ed skbs (or a part of it) for sure but never gave a hint to tcp_sacktag_one when dsack is actually in use. Thus DSACK retrans_out -= pcount was not taken and the counter became out of sync. Remove obstacle from that information flow to get DSACKs accounted in tcp_sacktag_one as expected. Signed-off-by: Ilpo Järvinen Tested-by: Denys Fedoryshchenko Signed-off-by: David S. Miller --- net/ipv4/tcp_input.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index a6961d75c7e..c28976a7e59 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1374,7 +1374,8 @@ static u8 tcp_sacktag_one(struct sk_buff *skb, struct sock *sk, static int tcp_shifted_skb(struct sock *sk, struct sk_buff *skb, struct tcp_sacktag_state *state, - unsigned int pcount, int shifted, int mss) + unsigned int pcount, int shifted, int mss, + int dup_sack) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *prev = tcp_write_queue_prev(sk, skb); @@ -1410,7 +1411,7 @@ static int tcp_shifted_skb(struct sock *sk, struct sk_buff *skb, } /* We discard results */ - tcp_sacktag_one(skb, sk, state, 0, pcount); + tcp_sacktag_one(skb, sk, state, dup_sack, pcount); /* Difference in this won't matter, both ACKed by the same cumul. ACK */ TCP_SKB_CB(prev)->sacked |= (TCP_SKB_CB(skb)->sacked & TCPCB_EVER_RETRANS); @@ -1561,7 +1562,7 @@ static struct sk_buff *tcp_shift_skb_data(struct sock *sk, struct sk_buff *skb, if (!skb_shift(prev, skb, len)) goto fallback; - if (!tcp_shifted_skb(sk, skb, state, pcount, len, mss)) + if (!tcp_shifted_skb(sk, skb, state, pcount, len, mss, dup_sack)) goto out; /* Hole filled allows collapsing with the next as well, this is very @@ -1580,7 +1581,7 @@ static struct sk_buff *tcp_shift_skb_data(struct sock *sk, struct sk_buff *skb, len = skb->len; if (skb_shift(prev, skb, len)) { pcount += tcp_skb_pcount(skb); - tcp_shifted_skb(sk, skb, state, tcp_skb_pcount(skb), len, mss); + tcp_shifted_skb(sk, skb, state, tcp_skb_pcount(skb), len, mss, 0); } out: -- 2.20.1