4 files changed, 39 insertions, 1 deletions

diff --git a/net/tipc/discover.c b/net/tipc/discover.c
index fc1fcf5e6b53..f28d1ae93125 100644
--- a/net/tipc/discover.c
+++ b/net/tipc/discover.c
@@ -203,6 +203,14 @@ void tipc_disc_recv_msg(struct sk_buff *buf, struct bearer *b_ptr)
 				return;
 		}
 		spin_lock_bh(&n_ptr->lock);
+
+		/* Don't talk to neighbor during cleanup after last session */
+
+		if (n_ptr->cleanup_required) {
+			spin_unlock_bh(&n_ptr->lock);
+			return;
+		}
+
 		link = n_ptr->links[b_ptr->identity];
 		if (!link) {
 			dbg("creating link\n");
diff --git a/net/tipc/link.c b/net/tipc/link.c
index 9d18c9b7638b..a6a3102bb4d6 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -1869,13 +1869,22 @@ void tipc_recv_msg(struct sk_buff *head, struct tipc_bearer *tb_ptr)
 				goto cont;
 		}
 
-		/* Locate unicast link endpoint that should handle message */
+		/* Locate neighboring node that sent message */
 
 		n_ptr = tipc_node_find(msg_prevnode(msg));
 		if (unlikely(!n_ptr))
 			goto cont;
 		tipc_node_lock(n_ptr);
 
+		/* Don't talk to neighbor during cleanup after last session */
+
+		if (n_ptr->cleanup_required) {
+			tipc_node_unlock(n_ptr);
+			goto cont;
+		}
+
+		/* Locate unicast link endpoint that should handle message */
+
 		l_ptr = n_ptr->links[b_ptr->identity];
 		if (unlikely(!l_ptr)) {
 			tipc_node_unlock(n_ptr);
diff --git a/net/tipc/node.c b/net/tipc/node.c
index 940851797615..b702c7bf580f 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -383,6 +383,20 @@ static void node_established_contact(struct tipc_node *n_ptr)
 				  tipc_highest_allowed_slave);
 }
 
+static void node_cleanup_finished(unsigned long node_addr)
+{
+	struct tipc_node *n_ptr;
+
+	read_lock_bh(&tipc_net_lock);
+	n_ptr = tipc_node_find(node_addr);
+	if (n_ptr) {
+		tipc_node_lock(n_ptr);
+		n_ptr->cleanup_required = 0;
+		tipc_node_unlock(n_ptr);
+	}
+	read_unlock_bh(&tipc_net_lock);
+}
+
 static void node_lost_contact(struct tipc_node *n_ptr)
 {
 	struct cluster *c_ptr;
@@ -457,6 +471,11 @@ static void node_lost_contact(struct tipc_node *n_ptr)
 		tipc_k_signal((Handler)ns->handle_node_down,
 			      (unsigned long)ns->usr_handle);
 	}
+
+	/* Prevent re-contact with node until all cleanup is done */
+
+	n_ptr->cleanup_required = 1;
+	tipc_k_signal((Handler)node_cleanup_finished, n_ptr->addr);
 }
 
 /**
diff --git a/net/tipc/node.h b/net/tipc/node.h
index 6f990da5d143..45f3db3a595d 100644
--- a/net/tipc/node.h
+++ b/net/tipc/node.h
@@ -52,6 +52,7 @@
  * @active_links: pointers to active links to node
  * @links: pointers to all links to node
  * @working_links: number of working links to node (both active and standby)
+ * @cleanup_required: non-zero if cleaning up after a prior loss of contact
  * @link_cnt: number of links to node
  * @permit_changeover: non-zero if node has redundant links to this system
  * @routers: bitmap (used for multicluster communication)
@@ -78,6 +79,7 @@ struct tipc_node {
 	struct link *links[MAX_BEARERS];
 	int link_cnt;
 	int working_links;
+	int cleanup_required;
 	int permit_changeover;
 	u32 routers[512/32];
 	int last_router;