inet{6}_request_sock: Init ->opt and ->pktopts in the constructor

Wei Yongjun noticed that we may call reqsk_free on request sock objects where
the opt fields may not be initialized, fix it by introducing inet_reqsk_alloc
where we initialize ->opt to NULL and set ->pktopts to NULL in
inet6_reqsk_alloc.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c
index 73ba989..d182a2a 100644
--- a/net/ipv4/syncookies.c
+++ b/net/ipv4/syncookies.c
@@ -285,7 +285,7 @@
 		cookie_check_timestamp(&tcp_opt);
 
 	ret = NULL;
-	req = reqsk_alloc(&tcp_request_sock_ops); /* for safety */
+	req = inet_reqsk_alloc(&tcp_request_sock_ops); /* for safety */
 	if (!req)
 		goto out;
 
@@ -301,7 +301,6 @@
 	ireq->rmt_port		= th->source;
 	ireq->loc_addr		= ip_hdr(skb)->daddr;
 	ireq->rmt_addr		= ip_hdr(skb)->saddr;
-	ireq->opt		= NULL;
 	ireq->snd_wscale	= tcp_opt.snd_wscale;
 	ireq->rcv_wscale	= tcp_opt.rcv_wscale;
 	ireq->sack_ok		= tcp_opt.sack_ok;