tcp: Revert per-route SACK/DSACK/TIMESTAMP changes.

It creates a regression, triggering badness for SYN_RECV
sockets, for example:

[19148.022102] Badness at net/ipv4/inet_connection_sock.c:293
[19148.022570] NIP: c02a0914 LR: c02a0904 CTR: 00000000
[19148.023035] REGS: eeecbd30 TRAP: 0700   Not tainted  (2.6.32)
[19148.023496] MSR: 00029032 <EE,ME,CE,IR,DR>  CR: 24002442  XER: 00000000
[19148.024012] TASK = eee9a820[1756] 'privoxy' THREAD: eeeca000

This is likely caused by the change in the 'estab' parameter
passed to tcp_parse_options() when invoked by the functions
in net/ipv4/tcp_minisocks.c

But even if that is fixed, the ->conn_request() changes made in
this patch series is fundamentally wrong.  They try to use the
listening socket's 'dst' to probe the route settings.  The
listening socket doesn't even have a route, and you can't
get the right route (the child request one) until much later
after we setup all of the state, and it must be done by hand.

This stuff really isn't ready, so the best thing to do is a
full revert.  This reverts the following commits:

f55017a93f1a74d50244b1254b9a2bd7ac9bbf7d
022c3f7d82f0f1c68018696f2f027b87b9bb45c2
1aba721eba1d84a2defce45b950272cee1e6c72a
cda42ebd67ee5fdf09d7057b5a4584d36fe8a335
345cda2fd695534be5a4494f1b59da9daed33663
dc343475ed062e13fc260acccaab91d7d80fd5b2
05eaade2782fb0c90d3034fd7a7d5a16266182bb
6a2a2d6bf8581216e08be15fcb563cfd6c430e1e

Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 14 insertions, 17 deletions

diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c
index 5b9af508b8f2..7208a06576c6 100644
--- a/net/ipv6/syncookies.c
+++ b/net/ipv6/syncookies.c
@@ -185,6 +185,13 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
 
 	NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_SYNCOOKIESRECV);
 
+	/* check for timestamp cookie support */
+	memset(&tcp_opt, 0, sizeof(tcp_opt));
+	tcp_parse_options(skb, &tcp_opt, &hash_location, 0);
+
+	if (tcp_opt.saw_tstamp)
+		cookie_check_timestamp(&tcp_opt);
+
 	ret = NULL;
 	req = inet6_reqsk_alloc(&tcp6_request_sock_ops);
 	if (!req)
@@ -218,6 +225,12 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
 	req->expires = 0UL;
 	req->retrans = 0;
 	ireq->ecn_ok		= 0;
+	ireq->snd_wscale	= tcp_opt.snd_wscale;
+	ireq->rcv_wscale	= tcp_opt.rcv_wscale;
+	ireq->sack_ok		= tcp_opt.sack_ok;
+	ireq->wscale_ok		= tcp_opt.wscale_ok;
+	ireq->tstamp_ok		= tcp_opt.saw_tstamp;
+	req->ts_recent		= tcp_opt.saw_tstamp ? tcp_opt.rcv_tsval : 0;
 	treq->rcv_isn = ntohl(th->seq) - 1;
 	treq->snt_isn = cookie;
 
@@ -253,21 +266,6 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
 			goto out_free;
 	}
 
-	/* check for timestamp cookie support */
-	memset(&tcp_opt, 0, sizeof(tcp_opt));
-	tcp_parse_options(skb, &tcp_opt, &hash_location, 0, dst);
-
-	if (tcp_opt.saw_tstamp)
-		cookie_check_timestamp(&tcp_opt);
-
-	req->ts_recent          = tcp_opt.saw_tstamp ? tcp_opt.rcv_tsval : 0;
-
-	ireq->snd_wscale        = tcp_opt.snd_wscale;
-	ireq->rcv_wscale        = tcp_opt.rcv_wscale;
-	ireq->sack_ok           = tcp_opt.sack_ok;
-	ireq->wscale_ok         = tcp_opt.wscale_ok;
-	ireq->tstamp_ok         = tcp_opt.saw_tstamp;
-
 	req->window_clamp = tp->window_clamp ? :dst_metric(dst, RTAX_WINDOW);
 	tcp_select_initial_window(tcp_full_space(sk), req->mss,
 				  &req->rcv_wnd, &req->window_clamp,
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index ee9cf62458d4..febfd595a40d 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1169,7 +1169,6 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
 	struct inet6_request_sock *treq;
 	struct ipv6_pinfo *np = inet6_sk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
-	struct dst_entry *dst = __sk_dst_get(sk);
 	__u32 isn = TCP_SKB_CB(skb)->when;
 #ifdef CONFIG_SYN_COOKIES
 	int want_cookie = 0;
@@ -1208,7 +1207,7 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
 	tcp_clear_options(&tmp_opt);
 	tmp_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr);
 	tmp_opt.user_mss = tp->rx_opt.user_mss;
-	tcp_parse_options(skb, &tmp_opt, &hash_location, 0, dst);
+	tcp_parse_options(skb, &tmp_opt, &hash_location, 0);
 
 	if (tmp_opt.cookie_plus > 0 &&
 	    tmp_opt.saw_tstamp &&