Commit 8c68b1a0 authored by Ursula Braun's avatar Ursula Braun Committed by David S. Miller
Browse files

Subject: [PATCH] af_iucv: drop skbs rejected by filter 



A packet filter might be installed for instance with setsockopt
SO_ATTACH_FILTER. af_iucv currently queues skbs rejected by filter
into the backlog queue. This does not make sense, since packets
rejected by filter can be dropped immediately. This patch adds
separate sk_filter return code checking, and dropping of packets
if applicable.

Signed-off-by: default avatarUrsula Braun <ubraun@linux.vnet.ibm.com>
Reported-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 4e0ad322

net/iucv/af_iucv.c

+17 −7
Original line number Diff line number Diff line
@@ -1323,8 +1323,13 @@ static void iucv_process_message(struct sock *sk, struct sk_buff *skb, 
	}



	IUCV_SKB_CB(skb)->offset = 0;

	if (sock_queue_rcv_skb(sk, skb))

		skb_queue_head(&iucv_sk(sk)->backlog_skb_q, skb);

	if (sk_filter(sk, skb)) {

		atomic_inc(&sk->sk_drops);	/* skb rejected by filter */

		kfree_skb(skb);

		return;

	}

	if (__sock_queue_rcv_skb(sk, skb))	/* handle rcv queue full */

		skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);

}



/* iucv_process_message_q() - Process outstanding IUCV messages
@@ -1438,13 +1443,13 @@ static int iucv_sock_recvmsg(struct socket *sock, struct msghdr *msg, 
		rskb = skb_dequeue(&iucv->backlog_skb_q);

		while (rskb) {

			IUCV_SKB_CB(rskb)->offset = 0;

			if (sock_queue_rcv_skb(sk, rskb)) {

			if (__sock_queue_rcv_skb(sk, rskb)) {

				/* handle rcv queue full */

				skb_queue_head(&iucv->backlog_skb_q,

						rskb);

				break;

			} else {

				rskb = skb_dequeue(&iucv->backlog_skb_q);

			}

			rskb = skb_dequeue(&iucv->backlog_skb_q);

		}

		if (skb_queue_empty(&iucv->backlog_skb_q)) {

			if (!list_empty(&iucv->message_q.list))
@@ -2124,12 +2129,17 @@ static int afiucv_hs_callback_rx(struct sock *sk, struct sk_buff *skb) 
	skb_reset_transport_header(skb);

	skb_reset_network_header(skb);

	IUCV_SKB_CB(skb)->offset = 0;

	if (sk_filter(sk, skb)) {

		atomic_inc(&sk->sk_drops);	/* skb rejected by filter */

		kfree_skb(skb);

		return NET_RX_SUCCESS;

	}



	spin_lock(&iucv->message_q.lock);

	if (skb_queue_empty(&iucv->backlog_skb_q)) {

		if (sock_queue_rcv_skb(sk, skb)) {

		if (__sock_queue_rcv_skb(sk, skb))

			/* handle rcv queue full */

			skb_queue_tail(&iucv->backlog_skb_q, skb);

		}

	} else

		skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);

	spin_unlock(&iucv->message_q.lock);

CRA Git | Maintained and supported by SUSTech CRA and CCSE