tipc: make function tipc_net_finalize() thread safe
authorJon Maloy <jon.maloy@ericsson.com>
Fri, 6 Jul 2018 18:10:06 +0000 (20:10 +0200)
committerDavid S. Miller <davem@davemloft.net>
Sat, 7 Jul 2018 10:49:02 +0000 (19:49 +0900)
The setting of the node address is not thread safe, meaning that
two discoverers may decide to set it simultanously, with a duplicate
entry in the name table as result. We fix that with this commit.

Fixes: 25b0b9c4e835 ("tipc: handle collisions of 32-bit node address hash values")
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/tipc/net.c

index 4fbaa0464405370601cb2fd1dd3b03733836d342..a7f6964c3a4b725a7cd06411dc1b5f3d48df778d 100644 (file)
@@ -121,12 +121,17 @@ int tipc_net_init(struct net *net, u8 *node_id, u32 addr)
 
 void tipc_net_finalize(struct net *net, u32 addr)
 {
-       tipc_set_node_addr(net, addr);
-       smp_mb();
-       tipc_named_reinit(net);
-       tipc_sk_reinit(net);
-       tipc_nametbl_publish(net, TIPC_CFG_SRV, addr, addr,
-                            TIPC_CLUSTER_SCOPE, 0, addr);
+       struct tipc_net *tn = tipc_net(net);
+
+       spin_lock_bh(&tn->node_list_lock);
+       if (!tipc_own_addr(net)) {
+               tipc_set_node_addr(net, addr);
+               tipc_named_reinit(net);
+               tipc_sk_reinit(net);
+               tipc_nametbl_publish(net, TIPC_CFG_SRV, addr, addr,
+                                    TIPC_CLUSTER_SCOPE, 0, addr);
+       }
+       spin_unlock_bh(&tn->node_list_lock);
 }
 
 void tipc_net_stop(struct net *net)