From 10cc2b50eb4b01ca4dc014af2094d28b4ebe20d7 Mon Sep 17 00:00:00 2001
From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Fri, 5 Mar 2010 21:03:35 +0000
Subject: [PATCH] bridge: Fix RCU race in br_multicast_stop
Thanks to Paul McKenny for pointing out that it is incorrect to use
synchronize_rcu_bh to ensure that pending callbacks have completed.
Instead we should use rcu_barrier_bh.
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/bridge/br_multicast.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index a1ffe1582c9a..12ce1eaa4f3e 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -1135,7 +1135,7 @@ void br_multicast_stop(struct net_bridge *br)
if (mdb->old) {
spin_unlock_bh(&br->multicast_lock);
- synchronize_rcu_bh();
+ rcu_barrier_bh();
spin_lock_bh(&br->multicast_lock);
WARN_ON(mdb->old);
}
--
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