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: Ursula Braun <ubraun@linux.vnet.ibm.com>
Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/iucv/af_iucv.c b/net/iucv/af_iucv.c
index 88d0eaa..cfb9e5f 100644
--- a/net/iucv/af_iucv.c
+++ b/net/iucv/af_iucv.c
@@ -1323,8 +1323,13 @@
}
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 @@
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 @@
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);