[PATCH 4.9 214/271] act_mirred: Fix mirred_init_module error handling

[Greg Kroah-Hartman]

From: YueHaibing <yuehaibing@xxxxxxxxxx>

[ Upstream commit 11c9a7d38af524217efb7a176ad322b97ac2f163 ]

If tcf_register_action failed, mirred_device_notifier
should be unregistered.

Fixes: 3b87956ea645 ("net sched: fix race in mirred device removal")
Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>
Signed-off-by: Jakub Kicinski <jakub.kicinski@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 net/sched/act_mirred.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index fc3650b061924..9b4c7c42c932d 100644
--- a/net/sched/act_mirred.c
+++ b/net/sched/act_mirred.c
@@ -332,7 +332,11 @@ static int __init mirred_init_module(void)
 		return err;
 
 	pr_info("Mirror/redirect action on\n");
-	return tcf_register_action(&act_mirred_ops, &mirred_net_ops);
+	err = tcf_register_action(&act_mirred_ops, &mirred_net_ops);
+	if (err)
+		unregister_netdevice_notifier(&mirred_device_notifier);
+
+	return err;
 }
 
 static void __exit mirred_cleanup_module(void)
-- 
2.20.1