Re: [PATCH net-next v8 06/11] net: ipv6: Use link netns in newlink() of rtnl_link_ops

[Kuniyuki Iwashima <kuniyu@amazon.com>]

From: Xiao Liang <shaw.leon@gmail.com>
Date: Mon, 13 Jan 2025 22:37:14 +0800
> diff --git a/drivers/net/bonding/bond_netlink.c b/drivers/net/bonding/bond_netlink.c
> index 2a6a424806aa..ac5e402c34bc 100644
> --- a/drivers/net/bonding/bond_netlink.c
> +++ b/drivers/net/bonding/bond_netlink.c
> @@ -564,10 +564,12 @@ static int bond_changelink(struct net_device *bond_dev, struct nlattr *tb[],
>  	return 0;
>  }
>  
> -static int bond_newlink(struct net *src_net, struct net_device *bond_dev,
> -			struct nlattr *tb[], struct nlattr *data[],
> +static int bond_newlink(struct net_device *bond_dev,
> +			struct rtnl_newlink_params *params,
>  			struct netlink_ext_ack *extack)
>  {
> +	struct nlattr **data = params->data;
> +	struct nlattr **tb = params->tb;
>  	int err;
>  
>  	err = bond_changelink(bond_dev, tb, data, extack);

Note that IFLA_BOND_ACTIVE_SLAVE uses dev_net(dev) for
__dev_get_by_index().


[...]
> diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
> index fed4fe2a4748..0c496aa1f706 100644
> --- a/drivers/net/macvlan.c
> +++ b/drivers/net/macvlan.c
> @@ -1565,11 +1565,12 @@ int macvlan_common_newlink(struct net *src_net, struct net_device *dev,
>  }
>  EXPORT_SYMBOL_GPL(macvlan_common_newlink);
>  
> -static int macvlan_newlink(struct net *src_net, struct net_device *dev,
> -			   struct nlattr *tb[], struct nlattr *data[],
> +static int macvlan_newlink(struct net_device *dev,
> +			   struct rtnl_newlink_params *params,
>  			   struct netlink_ext_ack *extack)
>  {
> -	return macvlan_common_newlink(src_net, dev, tb, data, extack);
> +	return macvlan_common_newlink(params->net, dev, params->tb,
> +				      params->data, extack);

Pass params as is as you did for ipvlan_link_new().

Same for macvtap_newlink().


[...]
> diff --git a/drivers/net/netkit.c b/drivers/net/netkit.c
> index 1e1b00756be7..1e9eadc77da2 100644
> --- a/drivers/net/netkit.c
> +++ b/drivers/net/netkit.c
> @@ -327,10 +327,13 @@ static int netkit_validate(struct nlattr *tb[], struct nlattr *data[],
>  
>  static struct rtnl_link_ops netkit_link_ops;
>  
> -static int netkit_new_link(struct net *peer_net, struct net_device *dev,
> -			   struct nlattr *tb[], struct nlattr *data[],
> +static int netkit_new_link(struct net_device *dev,
> +			   struct rtnl_newlink_params *params,
>  			   struct netlink_ext_ack *extack)
>  {
> +	struct nlattr **data = params->data;
> +	struct net *peer_net = params->net;
> +	struct nlattr **tb = params->tb;

nit: please keep the reverse xmas tree order.


>  	struct nlattr *peer_tb[IFLA_MAX + 1], **tbp = tb, *attr;

you can define *tbp here and initialise it later.

  	struct nlattr *peer_tb[IFLA_MAX + 1], **tbp, *attr;

>  	enum netkit_action policy_prim = NETKIT_PASS;
>  	enum netkit_action policy_peer = NETKIT_PASS;


[...]
> @@ -1064,6 +1067,11 @@ static void wwan_create_default_link(struct wwan_device *wwandev,
>  	struct net_device *dev;
>  	struct nlmsghdr *nlh;
>  	struct sk_buff *msg;
> +	struct rtnl_newlink_params params = {
> +		.net = &init_net,
> +		.tb = tb,
> +		.data = data,
> +	};

nit: Reverse xmas tree order


[...]
> diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
> index ec98349b9620..7ff5e96f6ba7 100644
> --- a/net/core/rtnetlink.c
> +++ b/net/core/rtnetlink.c
> @@ -3766,6 +3766,14 @@ static int rtnl_newlink_create(struct sk_buff *skb, struct ifinfomsg *ifm,
>  	struct net_device *dev;
>  	char ifname[IFNAMSIZ];
>  	int err;
> +	struct rtnl_newlink_params params = {

nit: Reverse xmas tree order


> +		.net = net,

Use sock_net(skb->sk) directly here and remove net defined above,
which is no longer used in this function.

---8<---
        unsigned char name_assign_type = NET_NAME_USER;
        struct rtnl_newlink_params params = {
                .net = sock_net(skb->sk),
                .src_net = net,
                .link_net = link_net,
                .peer_net = peer_net,
                .tb = tb,
                .data = data,
        };
        u32 portid = NETLINK_CB(skb).portid;
---8<---


[...]
> @@ -1698,6 +1702,10 @@ struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
>  	LIST_HEAD(list_kill);
>  	struct ip_tunnel *t;
>  	int err;
> +	struct rtnl_newlink_params params = {
> +		.net = net,
> +		.tb = tb,
> +	};
>  
>  	memset(&tb, 0, sizeof(tb));

nit: Reverse xmas tree