tcp: fix retrans_out leaks

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 <ilpo.jarvinen@helsinki.fi>
Tested-by: Denys Fedoryshchenko <denys@visp.net.lb>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Ilpo Järvinen 2009-03-01 00:21:36 -08:00 committed by David S. Miller
parent 709ab3261e
commit 9ec06ff57a

View file

@ -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, static int tcp_shifted_skb(struct sock *sk, struct sk_buff *skb,
struct tcp_sacktag_state *state, 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 tcp_sock *tp = tcp_sk(sk);
struct sk_buff *prev = tcp_write_queue_prev(sk, skb); 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 */ /* 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 */ /* 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); 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)) if (!skb_shift(prev, skb, len))
goto fallback; 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; goto out;
/* Hole filled allows collapsing with the next as well, this is very /* 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; len = skb->len;
if (skb_shift(prev, skb, len)) { if (skb_shift(prev, skb, len)) {
pcount += tcp_skb_pcount(skb); 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: out: