1 files changed, 37 insertions, 26 deletions

diff --git a/net/tipc/node.c b/net/tipc/node.c
index 9d2f4c2b08ab..4512e83652b1 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -263,6 +263,11 @@ static void tipc_node_write_lock(struct tipc_node *n)
         write_lock_bh(&n->lock);
 }
 
+static void tipc_node_write_unlock_fast(struct tipc_node *n)
+{
+        write_unlock_bh(&n->lock);
+}
+
 static void tipc_node_write_unlock(struct tipc_node *n)
 {
         struct net *net = n->net;
@@ -417,7 +422,7 @@ void tipc_node_subscribe(struct net *net, struct list_head *subscr, u32 addr)
         }
         tipc_node_write_lock(n);
         list_add_tail(subscr, &n->publ_list);
-        tipc_node_write_unlock(n);
+        tipc_node_write_unlock_fast(n);
         tipc_node_put(n);
 }
 
@@ -435,7 +440,7 @@ void tipc_node_unsubscribe(struct net *net, struct list_head *subscr, u32 addr)
         }
         tipc_node_write_lock(n);
         list_del_init(subscr);
-        tipc_node_write_unlock(n);
+        tipc_node_write_unlock_fast(n);
         tipc_node_put(n);
 }
 
@@ -1167,7 +1172,7 @@ msg_full:
  * @list: chain of buffers containing message
  * @dnode: address of destination node
  * @selector: a number used for deterministic link selection
- * Consumes the buffer chain, except when returning -ELINKCONG
+ * Consumes the buffer chain.
  * Returns 0 if success, otherwise: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE,-ENOBUF
  */
 int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
@@ -1206,10 +1211,10 @@ int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
         spin_unlock_bh(&le->lock);
         tipc_node_read_unlock(n);
 
-        if (likely(rc == 0))
-                tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr);
-        else if (rc == -ENOBUFS)
+        if (unlikely(rc == -ENOBUFS))
                 tipc_node_link_down(n, bearer_id, false);
+        else
+                tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr);
 
         tipc_node_put(n);
 
@@ -1221,20 +1226,15 @@ int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
  * messages, which will not be rejected
  * The only exception is datagram messages rerouted after secondary
  * lookup, which are rare and safe to dispose of anyway.
- * TODO: Return real return value, and let callers use
- * tipc_wait_for_sendpkt() where applicable
  */
 int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode,
                        u32 selector)
 {
         struct sk_buff_head head;
-        int rc;
 
         skb_queue_head_init(&head);
         __skb_queue_tail(&head, skb);
-        rc = tipc_node_xmit(net, &head, dnode, selector);
-        if (rc == -ELINKCONG)
-                kfree_skb(skb);
+        tipc_node_xmit(net, &head, dnode, selector);
         return 0;
 }
 
@@ -1262,6 +1262,19 @@ void tipc_node_broadcast(struct net *net, struct sk_buff *skb)
         kfree_skb(skb);
 }
 
+static void tipc_node_mcast_rcv(struct tipc_node *n)
+{
+        struct tipc_bclink_entry *be = &n->bc_entry;
+
+        /* 'arrvq' is under inputq2's lock protection */
+        spin_lock_bh(&be->inputq2.lock);
+        spin_lock_bh(&be->inputq1.lock);
+        skb_queue_splice_tail_init(&be->inputq1, &be->arrvq);
+        spin_unlock_bh(&be->inputq1.lock);
+        spin_unlock_bh(&be->inputq2.lock);
+        tipc_sk_mcast_rcv(n->net, &be->arrvq, &be->inputq2);
+}
+
 static void tipc_node_bc_sync_rcv(struct tipc_node *n, struct tipc_msg *hdr,
                                   int bearer_id, struct sk_buff_head *xmitq)
 {
@@ -1335,15 +1348,8 @@ static void tipc_node_bc_rcv(struct net *net, struct sk_buff *skb, int bearer_id
         if (!skb_queue_empty(&xmitq))
                 tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr);
 
-        /* Deliver. 'arrvq' is under inputq2's lock protection */
-        if (!skb_queue_empty(&be->inputq1)) {
-                spin_lock_bh(&be->inputq2.lock);
-                spin_lock_bh(&be->inputq1.lock);
-                skb_queue_splice_tail_init(&be->inputq1, &be->arrvq);
-                spin_unlock_bh(&be->inputq1.lock);
-                spin_unlock_bh(&be->inputq2.lock);
-                tipc_sk_mcast_rcv(net, &be->arrvq, &be->inputq2);
-        }
+        if (!skb_queue_empty(&be->inputq1))
+                tipc_node_mcast_rcv(n);
 
         if (rc & TIPC_LINK_DOWN_EVT) {
                 /* Reception reassembly failure => reset all links to peer */
@@ -1499,19 +1505,21 @@ void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
 {
         struct sk_buff_head xmitq;
         struct tipc_node *n;
-        struct tipc_msg *hdr = buf_msg(skb);
-        int usr = msg_user(hdr);
+        struct tipc_msg *hdr;
         int bearer_id = b->identity;
         struct tipc_link_entry *le;
-        u16 bc_ack = msg_bcast_ack(hdr);
         u32 self = tipc_own_addr(net);
-        int rc = 0;
+        int usr, rc = 0;
+        u16 bc_ack;
 
         __skb_queue_head_init(&xmitq);
 
-        /* Ensure message is well-formed */
+        /* Ensure message is well-formed before touching the header */
         if (unlikely(!tipc_msg_validate(skb)))
                 goto discard;
+        hdr = buf_msg(skb);
+        usr = msg_user(hdr);
+        bc_ack = msg_bcast_ack(hdr);
 
         /* Handle arrival of discovery or broadcast packet */
         if (unlikely(msg_non_seq(hdr))) {
@@ -1570,6 +1578,9 @@ void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
         if (unlikely(!skb_queue_empty(&n->bc_entry.namedq)))
                 tipc_named_rcv(net, &n->bc_entry.namedq);
 
+        if (unlikely(!skb_queue_empty(&n->bc_entry.inputq1)))
+                tipc_node_mcast_rcv(n);
+
         if (!skb_queue_empty(&le->inputq))
                 tipc_sk_rcv(net, &le->inputq);