af_key: fix info leaks in notify messages

key_notify_sa_flush() and key_notify_policy_flush() miss to initialize
the sadb_msg_reserved member of the broadcasted message and thereby
leak 2 bytes of heap memory to listeners. Fix that.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
static int pfkey_broadcast(struct sk_buff *skb, gfp_t allocation,
			   int broadcast_flags, struct sock *one_sk,
			   struct net *net)
{
	struct netns_pfkey *net_pfkey = net_generic(net, pfkey_net_id);
	struct sock *sk;
	struct sk_buff *skb2 = NULL;
	int err = -ESRCH;

	/* XXX Do we need something like netlink_overrun?  I think
	 * XXX PF_KEY socket apps will not mind current behavior.
	 */
	if (!skb)
		return -ENOMEM;

	rcu_read_lock();
	sk_for_each_rcu(sk, &net_pfkey->table) {
		struct pfkey_sock *pfk = pfkey_sk(sk);
		int err2;

		/* Yes, it means that if you are meant to receive this
		 * pfkey message you receive it twice as promiscuous
		 * socket.
		 */
		if (pfk->promisc)
			pfkey_broadcast_one(skb, &skb2, allocation, sk);

		/* the exact target will be processed later */
		if (sk == one_sk)
			continue;
		if (broadcast_flags != BROADCAST_ALL) {
			if (broadcast_flags & BROADCAST_PROMISC_ONLY)
				continue;
			if ((broadcast_flags & BROADCAST_REGISTERED) &&
			    !pfk->registered)
				continue;
			if (broadcast_flags & BROADCAST_ONE)
				continue;
		}

		err2 = pfkey_broadcast_one(skb, &skb2, allocation, sk);

		/* Error is cleare after succecful sending to at least one
		 * registered KM */
		if ((broadcast_flags & BROADCAST_REGISTERED) && err)
			err = err2;
	}
	rcu_read_unlock();

	if (one_sk != NULL)
		err = pfkey_broadcast_one(skb, &skb2, allocation, one_sk);

	kfree_skb(skb2);
	kfree_skb(skb);
	return err;
}

static int pfkey_broadcast(struct sk_buff *skb, gfp_t allocation,
			   int broadcast_flags, struct sock *one_sk,
			   struct net *net)
{
	struct netns_pfkey *net_pfkey = net_generic(net, pfkey_net_id);
	struct sock *sk;
	struct sk_buff *skb2 = NULL;
	int err = -ESRCH;

	/* XXX Do we need something like netlink_overrun?  I think
	 * XXX PF_KEY socket apps will not mind current behavior.
	 */
	if (!skb)
		return -ENOMEM;

	rcu_read_lock();
	sk_for_each_rcu(sk, &net_pfkey->table) {
		struct pfkey_sock *pfk = pfkey_sk(sk);
		int err2;

		/* Yes, it means that if you are meant to receive this
		 * pfkey message you receive it twice as promiscuous
		 * socket.
		 */
		if (pfk->promisc)
			pfkey_broadcast_one(skb, &skb2, allocation, sk);

		/* the exact target will be processed later */
		if (sk == one_sk)
			continue;
		if (broadcast_flags != BROADCAST_ALL) {
			if (broadcast_flags & BROADCAST_PROMISC_ONLY)
				continue;
			if ((broadcast_flags & BROADCAST_REGISTERED) &&
			    !pfk->registered)
				continue;
			if (broadcast_flags & BROADCAST_ONE)
				continue;
		}

		err2 = pfkey_broadcast_one(skb, &skb2, allocation, sk);

		/* Error is cleare after succecful sending to at least one
		 * registered KM */
		if ((broadcast_flags & BROADCAST_REGISTERED) && err)
			err = err2;
	}
	rcu_read_unlock();

	if (one_sk != NULL)
		err = pfkey_broadcast_one(skb, &skb2, allocation, one_sk);

	kfree_skb(skb2);
	kfree_skb(skb);
	return err;
}
