tcp: initialize variable ecn_ok in syncookies path

[ Upstream commit f0e3d0689da401f7d1981c2777a714ba295ea5ff ]

Using a gcc 4.4.3, warnings are emitted for a possibly uninitialized use
of ecn_ok.

This can happen if cookie_check_timestamp() returns due to not having
seen a timestamp.  Defaulting to ecn off seems like a reasonable thing
to do in this case, so initialized ecn_ok to false.

Signed-off-by: Mike Waychison <mikew@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c
index 2646149..4382629 100644
--- a/net/ipv4/syncookies.c
+++ b/net/ipv4/syncookies.c
@@ -276,7 +276,7 @@
 	int mss;
 	struct rtable *rt;
 	__u8 rcv_wscale;
-	bool ecn_ok;
+	bool ecn_ok = false;
 
 	if (!sysctl_tcp_syncookies || !th->ack || th->rst)
 		goto out;
diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c
index 8b9644a..14b8339 100644
--- a/net/ipv6/syncookies.c
+++ b/net/ipv6/syncookies.c
@@ -165,7 +165,7 @@
 	int mss;
 	struct dst_entry *dst;
 	__u8 rcv_wscale;
-	bool ecn_ok;
+	bool ecn_ok = false;
 
 	if (!sysctl_tcp_syncookies || !th->ack || th->rst)
 		goto out;