Merge branch 'tipc-next'

Jon Maloy says:

====================
tipc: some small fixes

When fix a minor buffer leak, and ensure that bearers filter packets
correctly while they are being shut down.

v2: Corrected typos in commit #3, as per feedback from S. Shtylyov
v3: Removed commit #3 from the series. Improved version will be
    re-submitted later.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

net/tipc/bearer.c

@@ -205,6 +205,7 @@ static int tipc_enable_bearer(struct net *net, const char *name,
 	struct tipc_bearer *b;
 	struct tipc_media *m;
 	struct tipc_bearer_names b_names;
+	struct sk_buff *skb;
 	char addr_string[16];
 	u32 bearer_id;
 	u32 with_this_prio;
@@ -301,7 +302,7 @@ static int tipc_enable_bearer(struct net *net, const char *name,
 	b->net_plane = bearer_id + 'A';
 	b->priority = priority;
 
-	res = tipc_disc_create(net, b, &b->bcast_addr);
+	res = tipc_disc_create(net, b, &b->bcast_addr, &skb);
 	if (res) {
 		bearer_disable(net, b);
 		pr_warn("Bearer <%s> rejected, discovery object creation failed\n",
@@ -310,7 +311,8 @@ static int tipc_enable_bearer(struct net *net, const char *name,
 	}
 
 	rcu_assign_pointer(tn->bearer_list[bearer_id], b);
-
+	if (skb)
+		tipc_bearer_xmit_skb(net, bearer_id, skb, &b->bcast_addr);
 	pr_info("Enabled bearer <%s>, discovery domain %s, priority %u\n",
 		name,
 		tipc_addr_string_fill(addr_string, disc_domain), priority);
@@ -335,23 +337,16 @@ static int tipc_reset_bearer(struct net *net, struct tipc_bearer *b)
  */
 static void bearer_disable(struct net *net, struct tipc_bearer *b)
 {
-	struct tipc_net *tn = net_generic(net, tipc_net_id);
-	u32 i;
+	struct tipc_net *tn = tipc_net(net);
+	int bearer_id = b->identity;
 
 	pr_info("Disabling bearer <%s>\n", b->name);
 	b->media->disable_media(b);
-
-	tipc_node_delete_links(net, b->identity);
+	tipc_node_delete_links(net, bearer_id);
 	RCU_INIT_POINTER(b->media_ptr, NULL);
 	if (b->link_req)
 		tipc_disc_delete(b->link_req);
-
-	for (i = 0; i < MAX_BEARERS; i++) {
-		if (b == rtnl_dereference(tn->bearer_list[i])) {
-			RCU_INIT_POINTER(tn->bearer_list[i], NULL);
-			break;
-		}
-	}
+	RCU_INIT_POINTER(tn->bearer_list[bearer_id], NULL);
 	kfree_rcu(b, rcu);
 }
 
@@ -394,7 +389,7 @@ void tipc_disable_l2_media(struct tipc_bearer *b)
 
 /**
  * tipc_l2_send_msg - send a TIPC packet out over an L2 interface
- * @buf: the packet to be sent
+ * @skb: the packet to be sent
  * @b: the bearer through which the packet is to be sent
  * @dest: peer destination address
  */
@@ -403,17 +398,21 @@ int tipc_l2_send_msg(struct net *net, struct sk_buff *skb,
 {
 	struct net_device *dev;
 	int delta;
+	void *tipc_ptr;
 
 	dev = (struct net_device *)rcu_dereference_rtnl(b->media_ptr);
 	if (!dev)
 		return 0;
 
+	/* Send RESET message even if bearer is detached from device */
+	tipc_ptr = rtnl_dereference(dev->tipc_ptr);
+	if (unlikely(!tipc_ptr && !msg_is_reset(buf_msg(skb))))
+		goto drop;
+
 	delta = dev->hard_header_len - skb_headroom(skb);
 	if ((delta > 0) &&
-	    pskb_expand_head(skb, SKB_DATA_ALIGN(delta), 0, GFP_ATOMIC)) {
-		kfree_skb(skb);
-		return 0;
-	}
+	    pskb_expand_head(skb, SKB_DATA_ALIGN(delta), 0, GFP_ATOMIC))
+		goto drop;
 
 	skb_reset_network_header(skb);
 	skb->dev = dev;
@@ -422,6 +421,9 @@ int tipc_l2_send_msg(struct net *net, struct sk_buff *skb,
 			dev->dev_addr, skb->len);
 	dev_queue_xmit(skb);
 	return 0;
+drop:
+	kfree_skb(skb);
+	return 0;
 }
 
 int tipc_bearer_mtu(struct net *net, u32 bearer_id)
@@ -450,6 +452,8 @@ void tipc_bearer_xmit_skb(struct net *net, u32 bearer_id,
 	b = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
 	if (likely(b))
 		b->media->send_msg(net, skb, b, dest);
+	else
+		kfree_skb(skb);
 	rcu_read_unlock();
 }
 
@@ -468,12 +472,12 @@ void tipc_bearer_xmit(struct net *net, u32 bearer_id,
 
 	rcu_read_lock();
 	b = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
-	if (likely(b)) {
+	if (unlikely(!b))
+		__skb_queue_purge(xmitq);
 	skb_queue_walk_safe(xmitq, skb, tmp) {
 		__skb_dequeue(xmitq);
 		b->media->send_msg(net, skb, b, dst);
 	}
-	}
 	rcu_read_unlock();
 }
 
@@ -490,7 +494,8 @@ void tipc_bearer_bc_xmit(struct net *net, u32 bearer_id,
 
 	rcu_read_lock();
 	b = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
-	if (likely(b)) {
+	if (unlikely(!b))
+		__skb_queue_purge(xmitq);
 	skb_queue_walk_safe(xmitq, skb, tmp) {
 		hdr = buf_msg(skb);
 		msg_set_non_seq(hdr, 1);
@@ -498,7 +503,6 @@ void tipc_bearer_bc_xmit(struct net *net, u32 bearer_id,
 		__skb_dequeue(xmitq);
 		b->media->send_msg(net, skb, b, &b->bcast_addr);
 	}
-	}
 	rcu_read_unlock();
 }
 
@@ -513,24 +517,21 @@ void tipc_bearer_bc_xmit(struct net *net, u32 bearer_id,
  * ignores packets sent using interface multicast, and traffic sent to other
  * nodes (which can happen if interface is running in promiscuous mode).
  */
-static int tipc_l2_rcv_msg(struct sk_buff *buf, struct net_device *dev,
+static int tipc_l2_rcv_msg(struct sk_buff *skb, struct net_device *dev,
 			   struct packet_type *pt, struct net_device *orig_dev)
 {
 	struct tipc_bearer *b;
 
 	rcu_read_lock();
 	b = rcu_dereference_rtnl(dev->tipc_ptr);
-	if (likely(b)) {
-		if (likely(buf->pkt_type <= PACKET_BROADCAST)) {
-			buf->next = NULL;
-			tipc_rcv(dev_net(dev), buf, b);
+	if (likely(b && (skb->pkt_type <= PACKET_BROADCAST))) {
+		skb->next = NULL;
+		tipc_rcv(dev_net(dev), skb, b);
 		rcu_read_unlock();
 		return NET_RX_SUCCESS;
 	}
-	}
 	rcu_read_unlock();
-
-	kfree_skb(buf);
+	kfree_skb(skb);
 	return NET_RX_DROP;
 }
 
@@ -548,9 +549,18 @@ static int tipc_l2_device_event(struct notifier_block *nb, unsigned long evt,
 {
 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 	struct net *net = dev_net(dev);
+	struct tipc_net *tn = tipc_net(net);
 	struct tipc_bearer *b;
+	int i;
 
 	b = rtnl_dereference(dev->tipc_ptr);
+	if (!b) {
+		for (i = 0; i < MAX_BEARERS; b = NULL, i++) {
+			b = rtnl_dereference(tn->bearer_list[i]);
+			if (b && (b->media_ptr == dev))
+				break;
+		}
+	}
 	if (!b)
 		return NOTIFY_DONE;
 
@@ -560,7 +570,14 @@ static int tipc_l2_device_event(struct notifier_block *nb, unsigned long evt,
 	case NETDEV_CHANGE:
 		if (netif_carrier_ok(dev))
 			break;
+	case NETDEV_UP:
+		rcu_assign_pointer(dev->tipc_ptr, b);
+		break;
 	case NETDEV_GOING_DOWN:
+		RCU_INIT_POINTER(dev->tipc_ptr, NULL);
+		synchronize_net();
+		tipc_reset_bearer(net, b);
+		break;
 	case NETDEV_CHANGEMTU:
 		tipc_reset_bearer(net, b);
 		break;

net/tipc/discover.c

@@ -268,10 +268,9 @@ static void disc_timeout(unsigned long data)
  * Returns 0 if successful, otherwise -errno.
  */
 int tipc_disc_create(struct net *net, struct tipc_bearer *b,
-		     struct tipc_media_addr *dest)
+		     struct tipc_media_addr *dest, struct sk_buff **skb)
 {
 	struct tipc_link_req *req;
-	struct sk_buff *skb;
 
 	req = kmalloc(sizeof(*req), GFP_ATOMIC);
 	if (!req)
@@ -293,9 +292,7 @@ int tipc_disc_create(struct net *net, struct tipc_bearer *b,
 	setup_timer(&req->timer, disc_timeout, (unsigned long)req);
 	mod_timer(&req->timer, jiffies + req->timer_intv);
 	b->link_req = req;
-	skb = skb_clone(req->buf, GFP_ATOMIC);
-	if (skb)
-		tipc_bearer_xmit_skb(net, req->bearer_id, skb, &req->dest);
+	*skb = skb_clone(req->buf, GFP_ATOMIC);
 	return 0;
 }
 

net/tipc/discover.h

@@ -40,7 +40,7 @@
 struct tipc_link_req;
 
 int tipc_disc_create(struct net *net, struct tipc_bearer *b_ptr,
-		     struct tipc_media_addr *dest);
+		     struct tipc_media_addr *dest, struct sk_buff **skb);
 void tipc_disc_delete(struct tipc_link_req *req);
 void tipc_disc_reset(struct net *net, struct tipc_bearer *b_ptr);
 void tipc_disc_add_dest(struct tipc_link_req *req);

net/tipc/msg.h

@@ -779,6 +779,11 @@ static inline bool msg_peer_node_is_up(struct tipc_msg *m)
 	return msg_redundant_link(m);
 }
 
+static inline bool msg_is_reset(struct tipc_msg *hdr)
+{
+	return (msg_user(hdr) == LINK_PROTOCOL) && (msg_type(hdr) == RESET_MSG);
+}
+
 struct sk_buff *tipc_buf_acquire(u32 size);
 bool tipc_msg_validate(struct sk_buff *skb);
 bool tipc_msg_reverse(u32 own_addr, struct sk_buff **skb, int err);