[DCCP]: Fix default sequence window size

When using the default sequence window size (100) I got the following in
my logs:

Jun 22 14:24:09 localhost kernel: [ 1492.114775] DCCP: Step 6 failed for
DATA packet, (LSWL(6279674225) <= P.seqno(6279674749) <=
S.SWH(6279674324)) and (P.ackno doesn't exist or LAWL(18798206530) <=
P.ackno(1125899906842620) <= S.AWH(18798206548), sending SYNC...
Jun 22 14:24:09 localhost kernel: [ 1492.115147] DCCP: Step 6 failed for
DATA packet, (LSWL(6279674225) <= P.seqno(6279674750) <=
S.SWH(6279674324)) and (P.ackno doesn't exist or LAWL(18798206530) <=
P.ackno(1125899906842620) <= S.AWH(18798206549), sending SYNC...

I went to alter the default sysctl and it didn't take for new sockets.
Below patch fixes this.

I think the default is too low but it is what the DCCP spec specifies.

As a side effect of this my rx speed using iperf goes from about 2.8 Mbits/sec
to 3.5. This is still far too slow but it is a step in the right direction.

Compile tested only for IPv6 but not particularly complex change.

Signed off by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 2 deletions

diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index ff42bc43263d..9f3d4d7cd0bf 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -31,6 +31,7 @@
 
 #include "dccp.h"
 #include "ipv6.h"
+#include "feat.h"
 
 /* Socket used for sending RSTs and ACKs */
 static struct socket *dccp_v6_ctl_socket;
@@ -707,8 +708,7 @@ static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
         ireq = inet_rsk(req);
         ipv6_addr_copy(&ireq6->rmt_addr, &skb->nh.ipv6h->saddr);
         ipv6_addr_copy(&ireq6->loc_addr, &skb->nh.ipv6h->daddr);
-        req->rcv_wnd    = 100; /* Fake, option parsing will get the
-                                  right value */
+        req->rcv_wnd    = dccp_feat_default_sequence_window;
         ireq6->pktopts  = NULL;
 
         if (ipv6_opt_accepted(sk, skb) ||