Re: [PATCH net-next v9 05/11] net: ip_tunnel: Use link netns in newlink() of rtnl_link_ops
From: Kuniyuki Iwashima <hidden>
Date: 2025-02-13 06:20:50
Also in:
batman, bpf, bridge, linux-can, linux-kselftest, linux-rdma, linux-wireless, lkml
From: Xiao Liang <redacted> Date: Mon, 10 Feb 2025 21:29:56 +0800
When link_net is set, use it as link netns instead of dev_net(). This prepares for rtnetlink core to create device in target netns directly, in which case the two namespaces may be different. Convert common ip_tunnel_newlink() to accept an extra link netns argument. Don't overwrite ip_tunnel.net in ip_tunnel_init().
Why... ? see a comment below. [...]
quoted hunk ↗ jump to hunk
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 1fe9b13d351c..26d15f907551 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c@@ -1413,7 +1413,8 @@ static int ipgre_newlink(struct net_device *dev, err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark); if (err < 0) return err; - return ip_tunnel_newlink(dev, tb, &p, fwmark); + return ip_tunnel_newlink(params->link_net ? : dev_net(dev), dev, tb, &p,
This is duplicate at all call sites, let's move it into ip_tunnel_newlink() by passing params.
quoted hunk ↗ jump to hunk
+ fwmark); } static int erspan_newlink(struct net_device *dev,diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c index 09b73acf037a..618a50d5c0c2 100644 --- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c@@ -1213,11 +1213,11 @@ void ip_tunnel_delete_nets(struct list_head *net_list, unsigned int id, } EXPORT_SYMBOL_GPL(ip_tunnel_delete_nets); -int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[], - struct ip_tunnel_parm_kern *p, __u32 fwmark) +int ip_tunnel_newlink(struct net *net, struct net_device *dev, + struct nlattr *tb[], struct ip_tunnel_parm_kern *p, + __u32 fwmark) { struct ip_tunnel *nt; - struct net *net = dev_net(dev); struct ip_tunnel_net *itn; int mtu; int err;@@ -1326,7 +1326,9 @@ int ip_tunnel_init(struct net_device *dev) } tunnel->dev = dev; - tunnel->net = dev_net(dev); + if (!tunnel->net) + tunnel->net = dev_net(dev);
Isn't tunnel->net always non-NULL ?
ip_tunnel_newlink
-> netdev_priv(dev)->net = net
-> register_netdevice(dev)
-> dev->netdev_ops->ndo_init(dev)
-> ip_tunnel_init(dev)
-> netdev_priv(dev)->net = dev_net(dev)