[PATCH 3.19.y-ckt 71/86] netfilter: nf_log: wait for rcu grace after logger unregistration

[Kamal Mostafa]

3.19.8-ckt9 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Pablo Neira Ayuso <pablo at netfilter.org>

commit ad5001cc7cdf9aaee5eb213fdee657e4a3c94776 upstream.

The nf_log_unregister() function needs to call synchronize_rcu() to make sure
that the objects are not dereferenced anymore on module removal.

Fixes: 5962815a6a56 ("netfilter: nf_log: use an array of loggers instead of list")
Signed-off-by: Pablo Neira Ayuso <pablo at netfilter.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 net/netfilter/nf_log.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c
index 43c926c..7ea79a2 100644
--- a/net/netfilter/nf_log.c
+++ b/net/netfilter/nf_log.c
@@ -113,6 +113,7 @@ void nf_log_unregister(struct nf_logger *logger)
 	for (i = 0; i < NFPROTO_NUMPROTO; i++)
 		RCU_INIT_POINTER(loggers[i][logger->type], NULL);
 	mutex_unlock(&nf_log_mutex);
+	synchronize_rcu();
 }
 EXPORT_SYMBOL(nf_log_unregister);
 
-- 
1.9.1