Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (29 commits)
  tcp: Restore ordering of TCP options for the sake of inter-operability
  net: Fix disjunct computation of netdev features
  sctp: Fix to handle SHUTDOWN in SHUTDOWN_RECEIVED state
  sctp: Fix to handle SHUTDOWN in SHUTDOWN-PENDING state
  sctp: Add check for the TSN field of the SHUTDOWN chunk
  sctp: Drop ICMP packet too big message with MTU larger than current PMTU
  p54: enable 2.4/5GHz spectrum by eeprom bits.
  orinoco: reduce stack usage in firmware download path
  ath5k: fix suspend-related oops on rmmod
  [netdrvr] fec_mpc52xx: Implement polling, to make netconsole work.
  qlge: Fix MSI/legacy single interrupt bug.
  smc911x: Make the driver safer on SMP
  smc911x: Add IRQ polarity configuration
  smc911x: Allow Kconfig dependency on ARM
  sis190: add identifier for Atheros AR8021 PHY
  8139x: reduce message severity on driver overlap
  igb: add IGB_DCA instead of selecting INTEL_IOATDMA
  igb: fix tx data corruption with transition to L0s on 82575
  ehea: Fix memory hotplug support
  netdev: DM9000: remove BLACKFIN hacking in DM9000 netdev driver
  ...

1 files changed, 18 insertions, 7 deletions

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 990a58493235..e4c5ac9fe89b 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -362,6 +362,17 @@ struct tcp_out_options {
 	__u32 tsval, tsecr;	/* need to include OPTION_TS */
 };
 
+/* Beware: Something in the Internet is very sensitive to the ordering of
+ * TCP options, we learned this through the hard way, so be careful here.
+ * Luckily we can at least blame others for their non-compliance but from
+ * inter-operatibility perspective it seems that we're somewhat stuck with
+ * the ordering which we have been using if we want to keep working with
+ * those broken things (not that it currently hurts anybody as there isn't
+ * particular reason why the ordering would need to be changed).
+ *
+ * At least SACK_PERM as the first option is known to lead to a disaster
+ * (but it may well be that other scenarios fail similarly).
+ */
 static void tcp_options_write(__be32 *ptr, struct tcp_sock *tp,
 			      const struct tcp_out_options *opts,
 			      __u8 **md5_hash) {
@@ -376,6 +387,12 @@ static void tcp_options_write(__be32 *ptr, struct tcp_sock *tp,
 		*md5_hash = NULL;
 	}
 
+	if (unlikely(opts->mss)) {
+		*ptr++ = htonl((TCPOPT_MSS << 24) |
+			       (TCPOLEN_MSS << 16) |
+			       opts->mss);
+	}
+
 	if (likely(OPTION_TS & opts->options)) {
 		if (unlikely(OPTION_SACK_ADVERTISE & opts->options)) {
 			*ptr++ = htonl((TCPOPT_SACK_PERM << 24) |
@@ -392,12 +409,6 @@ static void tcp_options_write(__be32 *ptr, struct tcp_sock *tp,
 		*ptr++ = htonl(opts->tsecr);
 	}
 
-	if (unlikely(opts->mss)) {
-		*ptr++ = htonl((TCPOPT_MSS << 24) |
-			       (TCPOLEN_MSS << 16) |
-			       opts->mss);
-	}
-
 	if (unlikely(OPTION_SACK_ADVERTISE & opts->options &&
 		     !(OPTION_TS & opts->options))) {
 		*ptr++ = htonl((TCPOPT_NOP << 24) |
@@ -432,7 +443,7 @@ static void tcp_options_write(__be32 *ptr, struct tcp_sock *tp,
 
 		if (tp->rx_opt.dsack) {
 			tp->rx_opt.dsack = 0;
-			tp->rx_opt.eff_sacks--;
+			tp->rx_opt.eff_sacks = tp->rx_opt.num_sacks;
 		}
 	}
 }