Re: [PATCH net v2] net: bareudp: add missing error handling for bareudp_link_config()
From: Cong Wang <hidden>
Date: 2021-01-05 20:39:47
On Tue, Jan 5, 2021 at 11:07 AM Jakub Kicinski [off-list ref] wrote:
.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
Thanks for the update. Just one question below.
quoted hunk ↗ jump to hunk
Fixes: 571912c69f0e ("net: UDP tunnel encapsulation module for tunnelling different protocols like MPLS, IP, NSH etc.") Signed-off-by: Jakub Kicinski <kuba@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);
Why do we need unregister_netdevice_many() here? I think bareudp_dellink(dev, NULL) is sufficient as we always have one instance to unregister? (For the same reason, bareudp_dev_create() does not need it either.) Thanks.