[TCP]: Two fixes to new sacktag code

1) Skip condition used to be wrong way around which made SACK
processing very broken, missed many blocks because of that.

2) Use highest_sack advancement only if some skbs are already
sacked because otherwise tcp_write_queue_next may move things
too far (occurs mainly with GSO). The other similar advancement
is not problem because highest_sack was previosly put to point
a sacked skb.

These problems were located because of problem report from Matt
Mathis <mathis@psc.edu>.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Ilpo Järvinen 2007-11-30 00:59:07 +11:00 committed by David S. Miller
parent df1b86c53d
commit ea4f76ae13

View file

@ -1384,7 +1384,7 @@ static struct sk_buff *tcp_sacktag_skip(struct sk_buff *skb, struct sock *sk,
if (skb == tcp_send_head(sk))
break;
if (before(TCP_SKB_CB(skb)->end_seq, skip_to_seq))
if (!before(TCP_SKB_CB(skb)->end_seq, skip_to_seq))
break;
}
return skb;
@ -1575,7 +1575,7 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_
continue;
}
if (!before(start_seq, tcp_highest_sack_seq(tp))) {
if (tp->sacked_out && !before(start_seq, tcp_highest_sack_seq(tp))) {
skb = tcp_write_queue_next(sk, tp->highest_sack);
fack_count = tp->fackets_out;
}