[PATCH net v2] net: bareudp: add missing error handling for bareudp_link_config()

[Jakub Kicinski]

.dellink does not get called after .newlink fails,
bareudp_newlink() must undo what bareudp_configure()
has done if bareudp_link_config() fails.

v2: call bareudp_dellink(), like bareudp_dev_create() does

Fixes: 571912c69f0e ("net: UDP tunnel encapsulation module for tunnelling 
different protocols like MPLS, IP, NSH etc.")
Signed-off-by: Jakub Kicinski <k...@kernel.org>
---
 drivers/net/bareudp.c | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/drivers/net/bareudp.c b/drivers/net/bareudp.c
index 708171c0d628..85de5f96c02b 100644
--- a/drivers/net/bareudp.c
+++ b/drivers/net/bareudp.c
@@ -645,11 +645,20 @@ static int bareudp_link_config(struct net_device *dev,
        return 0;
 }
 
+static void bareudp_dellink(struct net_device *dev, struct list_head *head)
+{
+       struct bareudp_dev *bareudp = netdev_priv(dev);
+
+       list_del(&bareudp->next);
+       unregister_netdevice_queue(dev, head);
+}
+
 static int bareudp_newlink(struct net *net, struct net_device *dev,
                           struct nlattr *tb[], struct nlattr *data[],
                           struct netlink_ext_ack *extack)
 {
        struct bareudp_conf conf;
+       LIST_HEAD(list_kill);
        int err;
 
        err = bareudp2info(data, &conf, extack);
@@ -662,17 +671,14 @@ static int bareudp_newlink(struct net *net, struct 
net_device *dev,
 
        err = bareudp_link_config(dev, tb);
        if (err)
-               return err;
+               goto err_unconfig;
 
        return 0;
-}
-
-static void bareudp_dellink(struct net_device *dev, struct list_head *head)
-{
-       struct bareudp_dev *bareudp = netdev_priv(dev);
 
-       list_del(&bareudp->next);
-       unregister_netdevice_queue(dev, head);
+err_unconfig:
+       bareudp_dellink(dev, &list_kill);
+       unregister_netdevice_many(&list_kill);
+       return err;
 }
 
 static size_t bareudp_get_size(const struct net_device *dev)
-- 
2.26.2