[PATCH] tun/tap: Add the missed return value check of register_netdevice_notifier

[Tonghao Zhang]

There is some codes of tun/tap module which did not check the return
value of register_netdevice_notifier. Add the check now.

Signed-off-by: Tonghao Zhang <xiangxia.m....@gmail.com>
---
 drivers/net/tun.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 3d4c245..32ad873 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -2598,8 +2598,16 @@ static int __init tun_init(void)
                goto err_misc;
        }
 
-       register_netdevice_notifier(&tun_notifier_block);
+       ret = register_netdevice_notifier(&tun_notifier_block);
+       if (ret) {
+               pr_err("Can't register netdevice notifier\n");
+               goto err_notifier;
+       }
+
        return  0;
+
+err_notifier:
+       misc_deregister(&tun_miscdev);
 err_misc:
        rtnl_link_unregister(&tun_link_ops);
 err_linkops:
-- 
1.8.3.1