ipv4: Fix fib_trie rebalancing, part 3
Alas current delaying of freeing old tnodes by RCU in trie_rebalance
is still not enough because we can free a top tnode before updating a
t->trie pointer.
Reported-by: Pawel Staszewski <pstaszewski@itcare.pl>
Tested-by: Pawel Staszewski <pstaszewski@itcare.pl>
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index 012cf5a..00a54b2 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -1021,6 +1021,9 @@
(struct node *)tn, wasfull);
tp = node_parent((struct node *) tn);
+ if (!tp)
+ rcu_assign_pointer(t->trie, (struct node *)tn);
+
tnode_free_flush();
if (!tp)
break;