[PATCH net-next v10 02/13] rtnetlink: Pack newlink() params into struct

[PATCH net-next v10 02/13] rtnetlink: Pack newlink() params into struct

[Xiao Liang]

There are 4 net namespaces involved when creating links:

 - source netns - where the netlink socket resides,
 - target netns - where to put the device being created,
 - link netns - netns associated with the device (backend),
 - peer netns - netns of peer device.

Currently, two nets are passed to newlink() callback - "src_net"
parameter and "dev_net" (implicitly in net_device). They are set as
follows, depending on netlink attributes in the request.

 +------------+-------------------+---------+---------+
 | peer netns | IFLA_LINK_NETNSID | src_net | dev_net |
 +------------+-------------------+---------+---------+
 |            | absent            | source  | target  |
 | absent     +-------------------+---------+---------+
 |            | present           | link    | link    |
 +------------+-------------------+---------+---------+
 |            | absent            | peer    | target  |
 | present    +-------------------+---------+---------+
 |            | present           | peer    | link    |
 +------------+-------------------+---------+---------+

When IFLA_LINK_NETNSID is present, the device is created in link netns
first and then moved to target netns. This has some side effects,
including extra ifindex allocation, ifname validation and link events.
These could be avoided if we create it in target netns from
the beginning.

On the other hand, the meaning of src_net parameter is ambiguous. It
varies depending on how parameters are passed. It is the effective
link (or peer netns) by design, but some drivers ignore it and use
dev_net instead.

To provide more netns context for drivers, this patch packs existing
newlink() parameters, along with the source netns, link netns and peer
netns, into a struct. The old "src_net" is renamed to "net" to avoid
confusion with real source netns, and will be deprecated later. The use
of src_net are converted to params->net trivially.

Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
---
 drivers/infiniband/ulp/ipoib/ipoib_netlink.c  |  7 ++++--
 drivers/net/amt.c                             |  7 ++++--
 drivers/net/bareudp.c                         |  7 ++++--
 drivers/net/bonding/bond_netlink.c            |  6 +++--
 drivers/net/can/dev/netlink.c                 |  4 +--
 drivers/net/can/vxcan.c                       |  7 ++++--
 .../ethernet/qualcomm/rmnet/rmnet_config.c    |  7 ++++--
 drivers/net/geneve.c                          |  7 ++++--
 drivers/net/gtp.c                             |  6 +++--
 drivers/net/ipvlan/ipvlan.h                   |  3 +--
 drivers/net/ipvlan/ipvlan_main.c              |  6 +++--
 drivers/net/ipvlan/ipvtap.c                   |  6 ++---
 drivers/net/macsec.c                          |  7 ++++--
 drivers/net/macvlan.c                         | 19 ++++++++------
 drivers/net/macvtap.c                         |  6 ++---
 drivers/net/netkit.c                          | 14 +++++++----
 drivers/net/pfcp.c                            |  5 ++--
 drivers/net/ppp/ppp_generic.c                 |  7 ++++--
 drivers/net/team/team_core.c                  |  6 +++--
 drivers/net/veth.c                            |  7 ++++--
 drivers/net/vrf.c                             |  5 ++--
 drivers/net/vxlan/vxlan_core.c                |  7 ++++--
 drivers/net/wireguard/device.c                |  5 ++--
 drivers/net/wireless/virtual/virt_wifi.c      |  6 +++--
 drivers/net/wwan/wwan_core.c                  | 16 +++++++++---
 include/linux/if_macvlan.h                    |  6 +++--
 include/net/rtnetlink.h                       | 25 ++++++++++++++++---
 net/8021q/vlan_netlink.c                      |  7 ++++--
 net/batman-adv/soft-interface.c               |  9 +++----
 net/bridge/br_netlink.c                       |  6 +++--
 net/caif/chnl_net.c                           |  5 ++--
 net/core/rtnetlink.c                          | 15 ++++++++---
 net/hsr/hsr_netlink.c                         |  6 +++--
 net/ieee802154/6lowpan/core.c                 |  5 ++--
 net/ipv4/ip_gre.c                             | 16 ++++++++----
 net/ipv4/ip_vti.c                             |  6 +++--
 net/ipv4/ipip.c                               |  6 +++--
 net/ipv6/ip6_gre.c                            | 14 ++++++++---
 net/ipv6/ip6_tunnel.c                         |  6 +++--
 net/ipv6/ip6_vti.c                            |  5 ++--
 net/ipv6/sit.c                                |  6 +++--
 net/xfrm/xfrm_interface_core.c                |  7 +++---
 42 files changed, 223 insertions(+), 110 deletions(-)

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_netlink.c b/drivers/infiniband/ulp/ipoib/ipoib_netlink.c
index 9ad8d9856275..16cb8ced9f35 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_netlink.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_netlink.c
@@ -97,10 +97,13 @@ static int ipoib_changelink(struct net_device *dev, struct nlattr *tb[],
 	return ret;
 }
 
-static int ipoib_new_child_link(struct net *src_net, struct net_device *dev,
-				struct nlattr *tb[], struct nlattr *data[],
+static int ipoib_new_child_link(struct net_device *dev,
+				struct rtnl_newlink_params *params,
 				struct netlink_ext_ack *extack)
 {
+	struct nlattr **data = params->data;
+	struct net *src_net = params->net;
+	struct nlattr **tb = params->tb;
 	struct net_device *pdev;
 	struct ipoib_dev_priv *ppriv;
 	u16 child_pkey;
diff --git a/drivers/net/amt.c b/drivers/net/amt.c
index 98c6205ed19f..96b7ec9a2c13 100644
--- a/drivers/net/amt.c
+++ b/drivers/net/amt.c
@@ -3161,11 +3161,14 @@ static int amt_validate(struct nlattr *tb[], struct nlattr *data[],
 	return 0;
 }
 
-static int amt_newlink(struct net *net, struct net_device *dev,
-		       struct nlattr *tb[], struct nlattr *data[],
+static int amt_newlink(struct net_device *dev,
+		       struct rtnl_newlink_params *params,
 		       struct netlink_ext_ack *extack)
 {
 	struct amt_dev *amt = netdev_priv(dev);
+	struct nlattr **data = params->data;
+	struct nlattr **tb = params->tb;
+	struct net *net = params->net;
 	int err = -EINVAL;
 
 	amt->net = net;
diff --git a/drivers/net/bareudp.c b/drivers/net/bareudp.c
index 70814303aab8..fc21dcfb4848 100644
--- a/drivers/net/bareudp.c
+++ b/drivers/net/bareudp.c
@@ -698,10 +698,13 @@ static void bareudp_dellink(struct net_device *dev, struct list_head *head)
 	unregister_netdevice_queue(dev, head);
 }
 
-static int bareudp_newlink(struct net *net, struct net_device *dev,
-			   struct nlattr *tb[], struct nlattr *data[],
+static int bareudp_newlink(struct net_device *dev,
+			   struct rtnl_newlink_params *params,
 			   struct netlink_ext_ack *extack)
 {
+	struct nlattr **data = params->data;
+	struct nlattr **tb = params->tb;
+	struct net *net = params->net;
 	struct bareudp_conf conf;
 	int err;
 
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);
diff --git a/drivers/net/can/dev/netlink.c b/drivers/net/can/dev/netlink.c
index 01aacdcda260..f1db9b7ffd4d 100644
--- a/drivers/net/can/dev/netlink.c
+++ b/drivers/net/can/dev/netlink.c
@@ -624,8 +624,8 @@ static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev)
 	return -EMSGSIZE;
 }
 
-static int can_newlink(struct net *src_net, struct net_device *dev,
-		       struct nlattr *tb[], struct nlattr *data[],
+static int can_newlink(struct net_device *dev,
+		       struct rtnl_newlink_params *params,
 		       struct netlink_ext_ack *extack)
 {
 	return -EOPNOTSUPP;
diff --git a/drivers/net/can/vxcan.c b/drivers/net/can/vxcan.c
index ca8811941085..6f8ebb1cfd7b 100644
--- a/drivers/net/can/vxcan.c
+++ b/drivers/net/can/vxcan.c
@@ -172,10 +172,13 @@ static void vxcan_setup(struct net_device *dev)
 /* forward declaration for rtnl_create_link() */
 static struct rtnl_link_ops vxcan_link_ops;
 
-static int vxcan_newlink(struct net *peer_net, struct net_device *dev,
-			 struct nlattr *tb[], struct nlattr *data[],
+static int vxcan_newlink(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;
 	struct vxcan_priv *priv;
 	struct net_device *peer;
 
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c
index f3bea196a8f9..8151e91395e2 100644
--- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c
@@ -117,11 +117,14 @@ static void rmnet_unregister_bridge(struct rmnet_port *port)
 	rmnet_unregister_real_device(bridge_dev);
 }
 
-static int rmnet_newlink(struct net *src_net, struct net_device *dev,
-			 struct nlattr *tb[], struct nlattr *data[],
+static int rmnet_newlink(struct net_device *dev,
+			 struct rtnl_newlink_params *params,
 			 struct netlink_ext_ack *extack)
 {
 	u32 data_format = RMNET_FLAGS_INGRESS_DEAGGREGATION;
+	struct nlattr **data = params->data;
+	struct net *src_net = params->net;
+	struct nlattr **tb = params->tb;
 	struct net_device *real_dev;
 	int mode = RMNET_EPMODE_VND;
 	struct rmnet_endpoint *ep;
diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index 642155cb8315..d373a851930c 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -1614,10 +1614,13 @@ static void geneve_link_config(struct net_device *dev,
 	geneve_change_mtu(dev, ldev_mtu - info->options_len);
 }
 
-static int geneve_newlink(struct net *net, struct net_device *dev,
-			  struct nlattr *tb[], struct nlattr *data[],
+static int geneve_newlink(struct net_device *dev,
+			  struct rtnl_newlink_params *params,
 			  struct netlink_ext_ack *extack)
 {
+	struct nlattr **data = params->data;
+	struct nlattr **tb = params->tb;
+	struct net *net = params->net;
 	struct geneve_config cfg = {
 		.df = GENEVE_DF_UNSET,
 		.use_udp6_rx_checksums = false,
diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c
index d64740bf44ed..d6d4326cb908 100644
--- a/drivers/net/gtp.c
+++ b/drivers/net/gtp.c
@@ -1462,10 +1462,12 @@ static int gtp_create_sockets(struct gtp_dev *gtp, const struct nlattr *nla,
 #define GTP_TH_MAXLEN	(sizeof(struct udphdr) + sizeof(struct gtp0_header))
 #define GTP_IPV6_MAXLEN	(sizeof(struct ipv6hdr) + GTP_TH_MAXLEN)
 
-static int gtp_newlink(struct net *src_net, struct net_device *dev,
-		       struct nlattr *tb[], struct nlattr *data[],
+static int gtp_newlink(struct net_device *dev,
+		       struct rtnl_newlink_params *params,
 		       struct netlink_ext_ack *extack)
 {
+	struct nlattr **data = params->data;
+	struct net *src_net = params->net;
 	unsigned int role = GTP_ROLE_GGSN;
 	struct gtp_dev *gtp;
 	struct gtp_net *gn;
diff --git a/drivers/net/ipvlan/ipvlan.h b/drivers/net/ipvlan/ipvlan.h
index 025e0c19ec25..50de3ee204db 100644
--- a/drivers/net/ipvlan/ipvlan.h
+++ b/drivers/net/ipvlan/ipvlan.h
@@ -166,8 +166,7 @@ struct ipvl_addr *ipvlan_addr_lookup(struct ipvl_port *port, void *lyr3h,
 void *ipvlan_get_L3_hdr(struct ipvl_port *port, struct sk_buff *skb, int *type);
 void ipvlan_count_rx(const struct ipvl_dev *ipvlan,
 		     unsigned int len, bool success, bool mcast);
-int ipvlan_link_new(struct net *src_net, struct net_device *dev,
-		    struct nlattr *tb[], struct nlattr *data[],
+int ipvlan_link_new(struct net_device *dev, struct rtnl_newlink_params *params,
 		    struct netlink_ext_ack *extack);
 void ipvlan_link_delete(struct net_device *dev, struct list_head *head);
 void ipvlan_link_setup(struct net_device *dev);
diff --git a/drivers/net/ipvlan/ipvlan_main.c b/drivers/net/ipvlan/ipvlan_main.c
index da3a97a65507..19ce19ca7e32 100644
--- a/drivers/net/ipvlan/ipvlan_main.c
+++ b/drivers/net/ipvlan/ipvlan_main.c
@@ -532,11 +532,13 @@ static int ipvlan_nl_fillinfo(struct sk_buff *skb,
 	return ret;
 }
 
-int ipvlan_link_new(struct net *src_net, struct net_device *dev,
-		    struct nlattr *tb[], struct nlattr *data[],
+int ipvlan_link_new(struct net_device *dev, struct rtnl_newlink_params *params,
 		    struct netlink_ext_ack *extack)
 {
 	struct ipvl_dev *ipvlan = netdev_priv(dev);
+	struct nlattr **data = params->data;
+	struct net *src_net = params->net;
+	struct nlattr **tb = params->tb;
 	struct ipvl_port *port;
 	struct net_device *phy_dev;
 	int err;
diff --git a/drivers/net/ipvlan/ipvtap.c b/drivers/net/ipvlan/ipvtap.c
index 1afc4c47be73..edd13916831a 100644
--- a/drivers/net/ipvlan/ipvtap.c
+++ b/drivers/net/ipvlan/ipvtap.c
@@ -73,8 +73,8 @@ static void ipvtap_update_features(struct tap_dev *tap,
 	netdev_update_features(vlan->dev);
 }
 
-static int ipvtap_newlink(struct net *src_net, struct net_device *dev,
-			  struct nlattr *tb[], struct nlattr *data[],
+static int ipvtap_newlink(struct net_device *dev,
+			  struct rtnl_newlink_params *params,
 			  struct netlink_ext_ack *extack)
 {
 	struct ipvtap_dev *vlantap = netdev_priv(dev);
@@ -97,7 +97,7 @@ static int ipvtap_newlink(struct net *src_net, struct net_device *dev,
 	/* Don't put anything that may fail after macvlan_common_newlink
 	 * because we can't undo what it does.
 	 */
-	err =  ipvlan_link_new(src_net, dev, tb, data, extack);
+	err = ipvlan_link_new(dev, params, extack);
 	if (err) {
 		netdev_rx_handler_unregister(dev);
 		return err;
diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c
index 1bc1e5993f56..1869b0513f57 100644
--- a/drivers/net/macsec.c
+++ b/drivers/net/macsec.c
@@ -4141,11 +4141,14 @@ static int macsec_add_dev(struct net_device *dev, sci_t sci, u8 icv_len)
 
 static struct lock_class_key macsec_netdev_addr_lock_key;
 
-static int macsec_newlink(struct net *net, struct net_device *dev,
-			  struct nlattr *tb[], struct nlattr *data[],
+static int macsec_newlink(struct net_device *dev,
+			  struct rtnl_newlink_params *params,
 			  struct netlink_ext_ack *extack)
 {
 	struct macsec_dev *macsec = macsec_priv(dev);
+	struct nlattr **data = params->data;
+	struct nlattr **tb = params->tb;
+	struct net *net = params->net;
 	rx_handler_func_t *rx_handler;
 	u8 icv_len = MACSEC_DEFAULT_ICV_LEN;
 	struct net_device *real_dev;
diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index fed4fe2a4748..f903b414eaeb 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -1440,16 +1440,19 @@ static int macvlan_changelink_sources(struct macvlan_dev *vlan, u32 mode,
 	return 0;
 }
 
-int macvlan_common_newlink(struct net *src_net, struct net_device *dev,
-			   struct nlattr *tb[], struct nlattr *data[],
+int macvlan_common_newlink(struct net_device *dev,
+			   struct rtnl_newlink_params *params,
 			   struct netlink_ext_ack *extack)
 {
 	struct macvlan_dev *vlan = netdev_priv(dev);
-	struct macvlan_port *port;
+	struct nlattr **data = params->data;
+	struct net *src_net = params->net;
+	struct nlattr **tb = params->tb;
 	struct net_device *lowerdev;
-	int err;
-	int macmode;
+	struct macvlan_port *port;
 	bool create = false;
+	int macmode;
+	int err;
 
 	if (!tb[IFLA_LINK])
 		return -EINVAL;
@@ -1565,11 +1568,11 @@ 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(dev, params, extack);
 }
 
 void macvlan_dellink(struct net_device *dev, struct list_head *head)
diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
index 29a5929d48e5..b391a0f740a3 100644
--- a/drivers/net/macvtap.c
+++ b/drivers/net/macvtap.c
@@ -77,8 +77,8 @@ static void macvtap_update_features(struct tap_dev *tap,
 	netdev_update_features(vlan->dev);
 }
 
-static int macvtap_newlink(struct net *src_net, struct net_device *dev,
-			   struct nlattr *tb[], struct nlattr *data[],
+static int macvtap_newlink(struct net_device *dev,
+			   struct rtnl_newlink_params *params,
 			   struct netlink_ext_ack *extack)
 {
 	struct macvtap_dev *vlantap = netdev_priv(dev);
@@ -105,7 +105,7 @@ static int macvtap_newlink(struct net *src_net, struct net_device *dev,
 	/* Don't put anything that may fail after macvlan_common_newlink
 	 * because we can't undo what it does.
 	 */
-	err = macvlan_common_newlink(src_net, dev, tb, data, extack);
+	err = macvlan_common_newlink(dev, params, extack);
 	if (err) {
 		netdev_rx_handler_unregister(dev);
 		return err;
diff --git a/drivers/net/netkit.c b/drivers/net/netkit.c
index 1e1b00756be7..640a2dbbbd28 100644
--- a/drivers/net/netkit.c
+++ b/drivers/net/netkit.c
@@ -327,17 +327,20 @@ 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 *peer_tb[IFLA_MAX + 1], **tbp = tb, *attr;
-	enum netkit_action policy_prim = NETKIT_PASS;
-	enum netkit_action policy_peer = NETKIT_PASS;
 	enum netkit_scrub scrub_prim = NETKIT_SCRUB_DEFAULT;
 	enum netkit_scrub scrub_peer = NETKIT_SCRUB_DEFAULT;
+	struct nlattr *peer_tb[IFLA_MAX + 1], **tbp, *attr;
+	enum netkit_action policy_prim = NETKIT_PASS;
+	enum netkit_action policy_peer = NETKIT_PASS;
+	struct nlattr **data = params->data;
+	struct net *peer_net = params->net;
 	enum netkit_mode mode = NETKIT_L3;
 	unsigned char ifname_assign_type;
+	struct nlattr **tb = params->tb;
 	u16 headroom = 0, tailroom = 0;
 	struct ifinfomsg *ifmp = NULL;
 	struct net_device *peer;
@@ -345,6 +348,7 @@ static int netkit_new_link(struct net *peer_net, struct net_device *dev,
 	struct netkit *nk;
 	int err;
 
+	tbp = tb;
 	if (data) {
 		if (data[IFLA_NETKIT_MODE])
 			mode = nla_get_u32(data[IFLA_NETKIT_MODE]);
diff --git a/drivers/net/pfcp.c b/drivers/net/pfcp.c
index 68d0d9e92a22..7b0575940e1d 100644
--- a/drivers/net/pfcp.c
+++ b/drivers/net/pfcp.c
@@ -184,11 +184,12 @@ static int pfcp_add_sock(struct pfcp_dev *pfcp)
 	return PTR_ERR_OR_ZERO(pfcp->sock);
 }
 
-static int pfcp_newlink(struct net *net, struct net_device *dev,
-			struct nlattr *tb[], struct nlattr *data[],
+static int pfcp_newlink(struct net_device *dev,
+			struct rtnl_newlink_params *params,
 			struct netlink_ext_ack *extack)
 {
 	struct pfcp_dev *pfcp = netdev_priv(dev);
+	struct net *net = params->net;
 	struct pfcp_net *pn;
 	int err;
 
diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c
index 4583e15ad03a..b3340f8a6149 100644
--- a/drivers/net/ppp/ppp_generic.c
+++ b/drivers/net/ppp/ppp_generic.c
@@ -1303,10 +1303,13 @@ static int ppp_nl_validate(struct nlattr *tb[], struct nlattr *data[],
 	return 0;
 }
 
-static int ppp_nl_newlink(struct net *src_net, struct net_device *dev,
-			  struct nlattr *tb[], struct nlattr *data[],
+static int ppp_nl_newlink(struct net_device *dev,
+			  struct rtnl_newlink_params *params,
 			  struct netlink_ext_ack *extack)
 {
+	struct nlattr **data = params->data;
+	struct net *src_net = params->net;
+	struct nlattr **tb = params->tb;
 	struct ppp_config conf = {
 		.unit = -1,
 		.ifname_is_set = true,
diff --git a/drivers/net/team/team_core.c b/drivers/net/team/team_core.c
index f4019815f473..78edb8186b6d 100644
--- a/drivers/net/team/team_core.c
+++ b/drivers/net/team/team_core.c
@@ -2218,10 +2218,12 @@ static void team_setup(struct net_device *dev)
 	dev->features |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX;
 }
 
-static int team_newlink(struct net *src_net, struct net_device *dev,
-			struct nlattr *tb[], struct nlattr *data[],
+static int team_newlink(struct net_device *dev,
+			struct rtnl_newlink_params *params,
 			struct netlink_ext_ack *extack)
 {
+	struct nlattr **tb = params->tb;
+
 	if (tb[IFLA_ADDRESS] == NULL)
 		eth_hw_addr_random(dev);
 
diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index 01251868a9c2..7dfda89f072f 100644
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c
@@ -1765,10 +1765,13 @@ static int veth_init_queues(struct net_device *dev, struct nlattr *tb[])
 	return 0;
 }
 
-static int veth_newlink(struct net *peer_net, struct net_device *dev,
-			struct nlattr *tb[], struct nlattr *data[],
+static int veth_newlink(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;
 	int err;
 	struct net_device *peer;
 	struct veth_priv *priv;
diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c
index 5f21ce1013c4..849c3ced2690 100644
--- a/drivers/net/vrf.c
+++ b/drivers/net/vrf.c
@@ -1675,11 +1675,12 @@ static void vrf_dellink(struct net_device *dev, struct list_head *head)
 	unregister_netdevice_queue(dev, head);
 }
 
-static int vrf_newlink(struct net *src_net, struct net_device *dev,
-		       struct nlattr *tb[], struct nlattr *data[],
+static int vrf_newlink(struct net_device *dev,
+		       struct rtnl_newlink_params *params,
 		       struct netlink_ext_ack *extack)
 {
 	struct net_vrf *vrf = netdev_priv(dev);
+	struct nlattr **data = params->data;
 	struct netns_vrf *nn_vrf;
 	bool *add_fib_rules;
 	struct net *net;
diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c
index ac5bc78edfd7..09a4a5bf1038 100644
--- a/drivers/net/vxlan/vxlan_core.c
+++ b/drivers/net/vxlan/vxlan_core.c
@@ -4400,10 +4400,13 @@ static int vxlan_nl2conf(struct nlattr *tb[], struct nlattr *data[],
 	return 0;
 }
 
-static int vxlan_newlink(struct net *src_net, struct net_device *dev,
-			 struct nlattr *tb[], struct nlattr *data[],
+static int vxlan_newlink(struct net_device *dev,
+			 struct rtnl_newlink_params *params,
 			 struct netlink_ext_ack *extack)
 {
+	struct nlattr **data = params->data;
+	struct net *src_net = params->net;
+	struct nlattr **tb = params->tb;
 	struct vxlan_config conf;
 	int err;
 
diff --git a/drivers/net/wireguard/device.c b/drivers/net/wireguard/device.c
index 6cf173a008e7..404cf05bd72b 100644
--- a/drivers/net/wireguard/device.c
+++ b/drivers/net/wireguard/device.c
@@ -307,11 +307,12 @@ static void wg_setup(struct net_device *dev)
 	wg->dev = dev;
 }
 
-static int wg_newlink(struct net *src_net, struct net_device *dev,
-		      struct nlattr *tb[], struct nlattr *data[],
+static int wg_newlink(struct net_device *dev,
+		      struct rtnl_newlink_params *params,
 		      struct netlink_ext_ack *extack)
 {
 	struct wg_device *wg = netdev_priv(dev);
+	struct net *src_net = params->net;
 	int ret = -ENOMEM;
 
 	rcu_assign_pointer(wg->creating_net, src_net);
diff --git a/drivers/net/wireless/virtual/virt_wifi.c b/drivers/net/wireless/virtual/virt_wifi.c
index 4ee374080466..26905b2b3ba3 100644
--- a/drivers/net/wireless/virtual/virt_wifi.c
+++ b/drivers/net/wireless/virtual/virt_wifi.c
@@ -519,11 +519,13 @@ static rx_handler_result_t virt_wifi_rx_handler(struct sk_buff **pskb)
 }
 
 /* Called with rtnl lock held. */
-static int virt_wifi_newlink(struct net *src_net, struct net_device *dev,
-			     struct nlattr *tb[], struct nlattr *data[],
+static int virt_wifi_newlink(struct net_device *dev,
+			     struct rtnl_newlink_params *params,
 			     struct netlink_ext_ack *extack)
 {
 	struct virt_wifi_netdev_priv *priv = netdev_priv(dev);
+	struct net *src_net = params->net;
+	struct nlattr **tb = params->tb;
 	int err;
 
 	if (!tb[IFLA_LINK])
diff --git a/drivers/net/wwan/wwan_core.c b/drivers/net/wwan/wwan_core.c
index a51e2755991a..a05c49b4e7f8 100644
--- a/drivers/net/wwan/wwan_core.c
+++ b/drivers/net/wwan/wwan_core.c
@@ -967,15 +967,18 @@ static struct net_device *wwan_rtnl_alloc(struct nlattr *tb[],
 	return dev;
 }
 
-static int wwan_rtnl_newlink(struct net *src_net, struct net_device *dev,
-			     struct nlattr *tb[], struct nlattr *data[],
+static int wwan_rtnl_newlink(struct net_device *dev,
+			     struct rtnl_newlink_params *params,
 			     struct netlink_ext_ack *extack)
 {
 	struct wwan_device *wwandev = wwan_dev_get_by_parent(dev->dev.parent);
-	u32 link_id = nla_get_u32(data[IFLA_WWAN_LINK_ID]);
 	struct wwan_netdev_priv *priv = netdev_priv(dev);
+	struct nlattr **data = params->data;
+	u32 link_id;
 	int ret;
 
+	link_id = nla_get_u32(data[IFLA_WWAN_LINK_ID]);
+
 	if (IS_ERR(wwandev))
 		return PTR_ERR(wwandev);
 
@@ -1061,6 +1064,11 @@ static void wwan_create_default_link(struct wwan_device *wwandev,
 {
 	struct nlattr *tb[IFLA_MAX + 1], *linkinfo[IFLA_INFO_MAX + 1];
 	struct nlattr *data[IFLA_WWAN_MAX + 1];
+	struct rtnl_newlink_params params = {
+		.net = &init_net,
+		.tb = tb,
+		.data = data,
+	};
 	struct net_device *dev;
 	struct nlmsghdr *nlh;
 	struct sk_buff *msg;
@@ -1105,7 +1113,7 @@ static void wwan_create_default_link(struct wwan_device *wwandev,
 	if (WARN_ON(IS_ERR(dev)))
 		goto unlock;
 
-	if (WARN_ON(wwan_rtnl_newlink(&init_net, dev, tb, data, NULL))) {
+	if (WARN_ON(wwan_rtnl_newlink(dev, &params, NULL))) {
 		free_netdev(dev);
 		goto unlock;
 	}
diff --git a/include/linux/if_macvlan.h b/include/linux/if_macvlan.h
index 523025106a64..0f7281e3e448 100644
--- a/include/linux/if_macvlan.h
+++ b/include/linux/if_macvlan.h
@@ -59,8 +59,10 @@ static inline void macvlan_count_rx(const struct macvlan_dev *vlan,
 
 extern void macvlan_common_setup(struct net_device *dev);
 
-extern int macvlan_common_newlink(struct net *src_net, struct net_device *dev,
-				  struct nlattr *tb[], struct nlattr *data[],
+struct rtnl_newlink_params;
+
+extern int macvlan_common_newlink(struct net_device *dev,
+				  struct rtnl_newlink_params *params,
 				  struct netlink_ext_ack *extack);
 
 extern void macvlan_dellink(struct net_device *dev, struct list_head *head);
diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h
index bc0069a8b6ea..563a6a27436c 100644
--- a/include/net/rtnetlink.h
+++ b/include/net/rtnetlink.h
@@ -69,6 +69,25 @@ static inline int rtnl_msg_family(const struct nlmsghdr *nlh)
 		return AF_UNSPEC;
 }
 
+/**
+ * struct rtnl_newlink_params - parameters of rtnl_link_ops::newlink()
+ *
+ * @net: Netns of interest
+ * @src_net: Source netns of rtnetlink socket
+ * @link_net: Link netns by IFLA_LINK_NETNSID, NULL if not specified
+ * @peer_net: Peer netns
+ * @tb: IFLA_* attributes
+ * @data: IFLA_INFO_DATA attributes
+ */
+struct rtnl_newlink_params {
+	struct net *net;
+	struct net *src_net;
+	struct net *link_net;
+	struct net *peer_net;
+	struct nlattr **tb;
+	struct nlattr **data;
+};
+
 /**
  *	struct rtnl_link_ops - rtnetlink link operations
  *
@@ -125,10 +144,8 @@ struct rtnl_link_ops {
 					    struct nlattr *data[],
 					    struct netlink_ext_ack *extack);
 
-	int			(*newlink)(struct net *src_net,
-					   struct net_device *dev,
-					   struct nlattr *tb[],
-					   struct nlattr *data[],
+	int			(*newlink)(struct net_device *dev,
+					   struct rtnl_newlink_params *params,
 					   struct netlink_ext_ack *extack);
 	int			(*changelink)(struct net_device *dev,
 					      struct nlattr *tb[],
diff --git a/net/8021q/vlan_netlink.c b/net/8021q/vlan_netlink.c
index 134419667d59..91df0f96e32a 100644
--- a/net/8021q/vlan_netlink.c
+++ b/net/8021q/vlan_netlink.c
@@ -135,11 +135,14 @@ static int vlan_changelink(struct net_device *dev, struct nlattr *tb[],
 	return 0;
 }
 
-static int vlan_newlink(struct net *src_net, struct net_device *dev,
-			struct nlattr *tb[], struct nlattr *data[],
+static int vlan_newlink(struct net_device *dev,
+			struct rtnl_newlink_params *params,
 			struct netlink_ext_ack *extack)
 {
 	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
+	struct nlattr **data = params->data;
+	struct net *src_net = params->net;
+	struct nlattr **tb = params->tb;
 	struct net_device *real_dev;
 	unsigned int max_mtu;
 	__be16 proto;
diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index 822d788a5f86..d893c8013261 100644
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -1077,19 +1077,18 @@ static int batadv_softif_validate(struct nlattr *tb[], struct nlattr *data[],
 
 /**
  * batadv_softif_newlink() - pre-initialize and register new batadv link
- * @src_net: the applicable net namespace
  * @dev: network device to register
- * @tb: IFLA_INFO_DATA netlink attributes
- * @data: enum batadv_ifla_attrs attributes
+ * @params: rtnl newlink parameters
  * @extack: extended ACK report struct
  *
  * Return: 0 if successful or error otherwise.
  */
-static int batadv_softif_newlink(struct net *src_net, struct net_device *dev,
-				 struct nlattr *tb[], struct nlattr *data[],
+static int batadv_softif_newlink(struct net_device *dev,
+				 struct rtnl_newlink_params *params,
 				 struct netlink_ext_ack *extack)
 {
 	struct batadv_priv *bat_priv = netdev_priv(dev);
+	struct nlattr **data = params->data;
 	const char *algo_name;
 	int err;
 
diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
index 3e0f47203f2a..6e337937d0d7 100644
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -1553,11 +1553,13 @@ static int br_changelink(struct net_device *brdev, struct nlattr *tb[],
 	return 0;
 }
 
-static int br_dev_newlink(struct net *src_net, struct net_device *dev,
-			  struct nlattr *tb[], struct nlattr *data[],
+static int br_dev_newlink(struct net_device *dev,
+			  struct rtnl_newlink_params *params,
 			  struct netlink_ext_ack *extack)
 {
 	struct net_bridge *br = netdev_priv(dev);
+	struct nlattr **data = params->data;
+	struct nlattr **tb = params->tb;
 	int err;
 
 	err = register_netdevice(dev);
diff --git a/net/caif/chnl_net.c b/net/caif/chnl_net.c
index 94ad09e36df2..fa6a3c2634a8 100644
--- a/net/caif/chnl_net.c
+++ b/net/caif/chnl_net.c
@@ -438,10 +438,11 @@ static void caif_netlink_parms(struct nlattr *data[],
 	}
 }
 
-static int ipcaif_newlink(struct net *src_net, struct net_device *dev,
-			  struct nlattr *tb[], struct nlattr *data[],
+static int ipcaif_newlink(struct net_device *dev,
+			  struct rtnl_newlink_params *params,
 			  struct netlink_ext_ack *extack)
 {
+	struct nlattr **data = params->data;
 	int ret;
 	struct chnl_net *caifdev;
 	ASSERT_RTNL();
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 0f3e2c6021de..9ebbde0d131c 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -3767,7 +3767,13 @@ static int rtnl_newlink_create(struct sk_buff *skb, struct ifinfomsg *ifm,
 			       struct netlink_ext_ack *extack)
 {
 	unsigned char name_assign_type = NET_NAME_USER;
-	struct net *net = sock_net(skb->sk);
+	struct rtnl_newlink_params params = {
+		.src_net = sock_net(skb->sk),
+		.link_net = link_net,
+		.peer_net = peer_net,
+		.tb = tb,
+		.data = data,
+	};
 	u32 portid = NETLINK_CB(skb).portid;
 	struct net_device *dev;
 	char ifname[IFNAMSIZ];
@@ -3792,13 +3798,14 @@ static int rtnl_newlink_create(struct sk_buff *skb, struct ifinfomsg *ifm,
 
 	dev->ifindex = ifm->ifi_index;
 
+	params.net = params.src_net;
 	if (link_net)
-		net = link_net;
+		params.net = link_net;
 	if (peer_net)
-		net = peer_net;
+		params.net = peer_net;
 
 	if (ops->newlink)
-		err = ops->newlink(net, dev, tb, data, extack);
+		err = ops->newlink(dev, &params, extack);
 	else
 		err = register_netdevice(dev);
 	if (err < 0) {
diff --git a/net/hsr/hsr_netlink.c b/net/hsr/hsr_netlink.c
index b68f2f71d0e1..39add538ba99 100644
--- a/net/hsr/hsr_netlink.c
+++ b/net/hsr/hsr_netlink.c
@@ -29,10 +29,12 @@ static const struct nla_policy hsr_policy[IFLA_HSR_MAX + 1] = {
 /* Here, it seems a netdevice has already been allocated for us, and the
  * hsr_dev_setup routine has been executed. Nice!
  */
-static int hsr_newlink(struct net *src_net, struct net_device *dev,
-		       struct nlattr *tb[], struct nlattr *data[],
+static int hsr_newlink(struct net_device *dev,
+		       struct rtnl_newlink_params *params,
 		       struct netlink_ext_ack *extack)
 {
+	struct nlattr **data = params->data;
+	struct net *src_net = params->net;
 	enum hsr_version proto_version;
 	unsigned char multicast_spec;
 	u8 proto = HSR_PROTOCOL_HSR;
diff --git a/net/ieee802154/6lowpan/core.c b/net/ieee802154/6lowpan/core.c
index 175efd860f7b..704bf9e3f097 100644
--- a/net/ieee802154/6lowpan/core.c
+++ b/net/ieee802154/6lowpan/core.c
@@ -129,10 +129,11 @@ static int lowpan_validate(struct nlattr *tb[], struct nlattr *data[],
 	return 0;
 }
 
-static int lowpan_newlink(struct net *src_net, struct net_device *ldev,
-			  struct nlattr *tb[], struct nlattr *data[],
+static int lowpan_newlink(struct net_device *ldev,
+			  struct rtnl_newlink_params *params,
 			  struct netlink_ext_ack *extack)
 {
+	struct nlattr **tb = params->tb;
 	struct net_device *wdev;
 	int ret;
 
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index c9f11a046c26..1fe9b13d351c 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -1396,10 +1396,12 @@ ipgre_newlink_encap_setup(struct net_device *dev, struct nlattr *data[])
 	return 0;
 }
 
-static int ipgre_newlink(struct net *src_net, struct net_device *dev,
-			 struct nlattr *tb[], struct nlattr *data[],
+static int ipgre_newlink(struct net_device *dev,
+			 struct rtnl_newlink_params *params,
 			 struct netlink_ext_ack *extack)
 {
+	struct nlattr **data = params->data;
+	struct nlattr **tb = params->tb;
 	struct ip_tunnel_parm_kern p;
 	__u32 fwmark = 0;
 	int err;
@@ -1414,10 +1416,12 @@ static int ipgre_newlink(struct net *src_net, struct net_device *dev,
 	return ip_tunnel_newlink(dev, tb, &p, fwmark);
 }
 
-static int erspan_newlink(struct net *src_net, struct net_device *dev,
-			  struct nlattr *tb[], struct nlattr *data[],
+static int erspan_newlink(struct net_device *dev,
+			  struct rtnl_newlink_params *params,
 			  struct netlink_ext_ack *extack)
 {
+	struct nlattr **data = params->data;
+	struct nlattr **tb = params->tb;
 	struct ip_tunnel_parm_kern p;
 	__u32 fwmark = 0;
 	int err;
@@ -1697,6 +1701,7 @@ static struct rtnl_link_ops erspan_link_ops __read_mostly = {
 struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
 					u8 name_assign_type)
 {
+	struct rtnl_newlink_params params = { .net = net };
 	struct nlattr *tb[IFLA_MAX + 1];
 	struct net_device *dev;
 	LIST_HEAD(list_kill);
@@ -1704,6 +1709,7 @@ struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
 	int err;
 
 	memset(&tb, 0, sizeof(tb));
+	params.tb = tb;
 
 	dev = rtnl_create_link(net, name, name_assign_type,
 			       &ipgre_tap_ops, tb, NULL);
@@ -1714,7 +1720,7 @@ struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
 	t = netdev_priv(dev);
 	t->collect_md = true;
 
-	err = ipgre_newlink(net, dev, tb, NULL, NULL);
+	err = ipgre_newlink(dev, &params, NULL);
 	if (err < 0) {
 		free_netdev(dev);
 		return ERR_PTR(err);
diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c
index f0b4419cef34..b901bee03e6d 100644
--- a/net/ipv4/ip_vti.c
+++ b/net/ipv4/ip_vti.c
@@ -575,11 +575,13 @@ static void vti_netlink_parms(struct nlattr *data[],
 		*fwmark = nla_get_u32(data[IFLA_VTI_FWMARK]);
 }
 
-static int vti_newlink(struct net *src_net, struct net_device *dev,
-		       struct nlattr *tb[], struct nlattr *data[],
+static int vti_newlink(struct net_device *dev,
+		       struct rtnl_newlink_params *params,
 		       struct netlink_ext_ack *extack)
 {
+	struct nlattr **data = params->data;
 	struct ip_tunnel_parm_kern parms;
+	struct nlattr **tb = params->tb;
 	__u32 fwmark = 0;
 
 	vti_netlink_parms(data, &parms, &fwmark);
diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c
index dc0db5895e0e..a8b844bcfc64 100644
--- a/net/ipv4/ipip.c
+++ b/net/ipv4/ipip.c
@@ -436,11 +436,13 @@ static void ipip_netlink_parms(struct nlattr *data[],
 		*fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]);
 }
 
-static int ipip_newlink(struct net *src_net, struct net_device *dev,
-			struct nlattr *tb[], struct nlattr *data[],
+static int ipip_newlink(struct net_device *dev,
+			struct rtnl_newlink_params *params,
 			struct netlink_ext_ack *extack)
 {
 	struct ip_tunnel *t = netdev_priv(dev);
+	struct nlattr **data = params->data;
+	struct nlattr **tb = params->tb;
 	struct ip_tunnel_encap ipencap;
 	struct ip_tunnel_parm_kern p;
 	__u32 fwmark = 0;
diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index 235808cfec70..863852abe8ea 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -2005,11 +2005,14 @@ static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
 	return err;
 }
 
-static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
-			  struct nlattr *tb[], struct nlattr *data[],
+static int ip6gre_newlink(struct net_device *dev,
+			  struct rtnl_newlink_params *params,
 			  struct netlink_ext_ack *extack)
 {
 	struct ip6_tnl *nt = netdev_priv(dev);
+	struct nlattr **data = params->data;
+	struct net *src_net = params->net;
+	struct nlattr **tb = params->tb;
 	struct net *net = dev_net(dev);
 	struct ip6gre_net *ign;
 	int err;
@@ -2241,11 +2244,14 @@ static void ip6erspan_tap_setup(struct net_device *dev)
 	netif_keep_dst(dev);
 }
 
-static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
-			     struct nlattr *tb[], struct nlattr *data[],
+static int ip6erspan_newlink(struct net_device *dev,
+			     struct rtnl_newlink_params *params,
 			     struct netlink_ext_ack *extack)
 {
 	struct ip6_tnl *nt = netdev_priv(dev);
+	struct nlattr **data = params->data;
+	struct net *src_net = params->net;
+	struct nlattr **tb = params->tb;
 	struct net *net = dev_net(dev);
 	struct ip6gre_net *ign;
 	int err;
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 48fd53b98972..54b843d20870 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -2002,10 +2002,12 @@ static void ip6_tnl_netlink_parms(struct nlattr *data[],
 		parms->fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]);
 }
 
-static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
-			   struct nlattr *tb[], struct nlattr *data[],
+static int ip6_tnl_newlink(struct net_device *dev,
+			   struct rtnl_newlink_params *params,
 			   struct netlink_ext_ack *extack)
 {
+	struct nlattr **data = params->data;
+	struct nlattr **tb = params->tb;
 	struct net *net = dev_net(dev);
 	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 	struct ip_tunnel_encap ipencap;
diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c
index 590737c27537..993f85aeb882 100644
--- a/net/ipv6/ip6_vti.c
+++ b/net/ipv6/ip6_vti.c
@@ -997,10 +997,11 @@ static void vti6_netlink_parms(struct nlattr *data[],
 		parms->fwmark = nla_get_u32(data[IFLA_VTI_FWMARK]);
 }
 
-static int vti6_newlink(struct net *src_net, struct net_device *dev,
-			struct nlattr *tb[], struct nlattr *data[],
+static int vti6_newlink(struct net_device *dev,
+			struct rtnl_newlink_params *params,
 			struct netlink_ext_ack *extack)
 {
+	struct nlattr **data = params->data;
 	struct net *net = dev_net(dev);
 	struct ip6_tnl *nt;
 
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 39bd8951bfca..e2bd52cabdee 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -1550,10 +1550,12 @@ static bool ipip6_netlink_6rd_parms(struct nlattr *data[],
 }
 #endif
 
-static int ipip6_newlink(struct net *src_net, struct net_device *dev,
-			 struct nlattr *tb[], struct nlattr *data[],
+static int ipip6_newlink(struct net_device *dev,
+			 struct rtnl_newlink_params *params,
 			 struct netlink_ext_ack *extack)
 {
+	struct nlattr **data = params->data;
+	struct nlattr **tb = params->tb;
 	struct net *net = dev_net(dev);
 	struct ip_tunnel *nt;
 	struct ip_tunnel_encap ipencap;
diff --git a/net/xfrm/xfrm_interface_core.c b/net/xfrm/xfrm_interface_core.c
index c397eb99d867..5659a6cadd51 100644
--- a/net/xfrm/xfrm_interface_core.c
+++ b/net/xfrm/xfrm_interface_core.c
@@ -814,10 +814,11 @@ static void xfrmi_netlink_parms(struct nlattr *data[],
 		parms->collect_md = true;
 }
 
-static int xfrmi_newlink(struct net *src_net, struct net_device *dev,
-			struct nlattr *tb[], struct nlattr *data[],
-			struct netlink_ext_ack *extack)
+static int xfrmi_newlink(struct net_device *dev,
+			 struct rtnl_newlink_params *params,
+			 struct netlink_ext_ack *extack)
 {
+	struct nlattr **data = params->data;
 	struct net *net = dev_net(dev);
 	struct xfrm_if_parms p = {};
 	struct xfrm_if *xi;
-- 
2.48.1

[PATCH net-next v10 03/13] net: Use link/peer netns in newlink() of rtnl_link_ops

[Xiao Liang]

Add two helper functions - rtnl_newlink_link_net() and
rtnl_newlink_peer_net() for netns fallback logic. Peer netns falls back
to link netns, and link netns falls back to source netns.

Convert the use of params->net in netdevice drivers to one of the helper
functions for clarity.

Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
---
 drivers/infiniband/ulp/ipoib/ipoib_netlink.c    |  4 ++--
 drivers/net/amt.c                               |  6 +++---
 drivers/net/bareudp.c                           |  4 ++--
 drivers/net/can/vxcan.c                         |  2 +-
 .../net/ethernet/qualcomm/rmnet/rmnet_config.c  |  4 ++--
 drivers/net/geneve.c                            |  4 ++--
 drivers/net/gtp.c                               |  6 +++---
 drivers/net/ipvlan/ipvlan_main.c                |  4 ++--
 drivers/net/macsec.c                            |  4 ++--
 drivers/net/macvlan.c                           |  4 ++--
 drivers/net/netkit.c                            |  2 +-
 drivers/net/pfcp.c                              |  6 +++---
 drivers/net/ppp/ppp_generic.c                   |  4 ++--
 drivers/net/veth.c                              |  2 +-
 drivers/net/vxlan/vxlan_core.c                  |  4 ++--
 drivers/net/wireguard/device.c                  |  4 ++--
 drivers/net/wireless/virtual/virt_wifi.c        |  4 ++--
 drivers/net/wwan/wwan_core.c                    |  2 +-
 include/net/rtnetlink.h                         | 17 +++++++++++++++++
 net/8021q/vlan_netlink.c                        |  4 ++--
 net/hsr/hsr_netlink.c                           |  8 ++++----
 21 files changed, 58 insertions(+), 41 deletions(-)

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_netlink.c b/drivers/infiniband/ulp/ipoib/ipoib_netlink.c
index 16cb8ced9f35..53db7c8191e3 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_netlink.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_netlink.c
@@ -101,8 +101,8 @@ static int ipoib_new_child_link(struct net_device *dev,
 				struct rtnl_newlink_params *params,
 				struct netlink_ext_ack *extack)
 {
+	struct net *link_net = rtnl_newlink_link_net(params);
 	struct nlattr **data = params->data;
-	struct net *src_net = params->net;
 	struct nlattr **tb = params->tb;
 	struct net_device *pdev;
 	struct ipoib_dev_priv *ppriv;
@@ -112,7 +112,7 @@ static int ipoib_new_child_link(struct net_device *dev,
 	if (!tb[IFLA_LINK])
 		return -EINVAL;
 
-	pdev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
+	pdev = __dev_get_by_index(link_net, nla_get_u32(tb[IFLA_LINK]));
 	if (!pdev || pdev->type != ARPHRD_INFINIBAND)
 		return -ENODEV;
 
diff --git a/drivers/net/amt.c b/drivers/net/amt.c
index 96b7ec9a2c13..53899b70fae1 100644
--- a/drivers/net/amt.c
+++ b/drivers/net/amt.c
@@ -3165,13 +3165,13 @@ static int amt_newlink(struct net_device *dev,
 		       struct rtnl_newlink_params *params,
 		       struct netlink_ext_ack *extack)
 {
+	struct net *link_net = rtnl_newlink_link_net(params);
 	struct amt_dev *amt = netdev_priv(dev);
 	struct nlattr **data = params->data;
 	struct nlattr **tb = params->tb;
-	struct net *net = params->net;
 	int err = -EINVAL;
 
-	amt->net = net;
+	amt->net = link_net;
 	amt->mode = nla_get_u32(data[IFLA_AMT_MODE]);
 
 	if (data[IFLA_AMT_MAX_TUNNELS] &&
@@ -3186,7 +3186,7 @@ static int amt_newlink(struct net_device *dev,
 	amt->hash_buckets = AMT_HSIZE;
 	amt->nr_tunnels = 0;
 	get_random_bytes(&amt->hash_seed, sizeof(amt->hash_seed));
-	amt->stream_dev = dev_get_by_index(net,
+	amt->stream_dev = dev_get_by_index(link_net,
 					   nla_get_u32(data[IFLA_AMT_LINK]));
 	if (!amt->stream_dev) {
 		NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_LINK],
diff --git a/drivers/net/bareudp.c b/drivers/net/bareudp.c
index fc21dcfb4848..d1473c5f8eef 100644
--- a/drivers/net/bareudp.c
+++ b/drivers/net/bareudp.c
@@ -702,9 +702,9 @@ static int bareudp_newlink(struct net_device *dev,
 			   struct rtnl_newlink_params *params,
 			   struct netlink_ext_ack *extack)
 {
+	struct net *link_net = rtnl_newlink_link_net(params);
 	struct nlattr **data = params->data;
 	struct nlattr **tb = params->tb;
-	struct net *net = params->net;
 	struct bareudp_conf conf;
 	int err;
 
@@ -712,7 +712,7 @@ static int bareudp_newlink(struct net_device *dev,
 	if (err)
 		return err;
 
-	err = bareudp_configure(net, dev, &conf, extack);
+	err = bareudp_configure(link_net, dev, &conf, extack);
 	if (err)
 		return err;
 
diff --git a/drivers/net/can/vxcan.c b/drivers/net/can/vxcan.c
index 6f8ebb1cfd7b..99a78a757167 100644
--- a/drivers/net/can/vxcan.c
+++ b/drivers/net/can/vxcan.c
@@ -176,8 +176,8 @@ static int vxcan_newlink(struct net_device *dev,
 			 struct rtnl_newlink_params *params,
 			 struct netlink_ext_ack *extack)
 {
+	struct net *peer_net = rtnl_newlink_peer_net(params);
 	struct nlattr **data = params->data;
-	struct net *peer_net = params->net;
 	struct nlattr **tb = params->tb;
 	struct vxcan_priv *priv;
 	struct net_device *peer;
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c
index 8151e91395e2..ba8763cac9d9 100644
--- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c
@@ -121,9 +121,9 @@ static int rmnet_newlink(struct net_device *dev,
 			 struct rtnl_newlink_params *params,
 			 struct netlink_ext_ack *extack)
 {
+	struct net *link_net = rtnl_newlink_link_net(params);
 	u32 data_format = RMNET_FLAGS_INGRESS_DEAGGREGATION;
 	struct nlattr **data = params->data;
-	struct net *src_net = params->net;
 	struct nlattr **tb = params->tb;
 	struct net_device *real_dev;
 	int mode = RMNET_EPMODE_VND;
@@ -137,7 +137,7 @@ static int rmnet_newlink(struct net_device *dev,
 		return -EINVAL;
 	}
 
-	real_dev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
+	real_dev = __dev_get_by_index(link_net, nla_get_u32(tb[IFLA_LINK]));
 	if (!real_dev) {
 		NL_SET_ERR_MSG_MOD(extack, "link does not exist");
 		return -ENODEV;
diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index d373a851930c..c7700deefb00 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -1618,9 +1618,9 @@ static int geneve_newlink(struct net_device *dev,
 			  struct rtnl_newlink_params *params,
 			  struct netlink_ext_ack *extack)
 {
+	struct net *link_net = rtnl_newlink_link_net(params);
 	struct nlattr **data = params->data;
 	struct nlattr **tb = params->tb;
-	struct net *net = params->net;
 	struct geneve_config cfg = {
 		.df = GENEVE_DF_UNSET,
 		.use_udp6_rx_checksums = false,
@@ -1634,7 +1634,7 @@ static int geneve_newlink(struct net_device *dev,
 	if (err)
 		return err;
 
-	err = geneve_configure(net, dev, extack, &cfg);
+	err = geneve_configure(link_net, dev, extack, &cfg);
 	if (err)
 		return err;
 
diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c
index d6d4326cb908..2cf43e7d0edc 100644
--- a/drivers/net/gtp.c
+++ b/drivers/net/gtp.c
@@ -1466,8 +1466,8 @@ static int gtp_newlink(struct net_device *dev,
 		       struct rtnl_newlink_params *params,
 		       struct netlink_ext_ack *extack)
 {
+	struct net *link_net = rtnl_newlink_link_net(params);
 	struct nlattr **data = params->data;
-	struct net *src_net = params->net;
 	unsigned int role = GTP_ROLE_GGSN;
 	struct gtp_dev *gtp;
 	struct gtp_net *gn;
@@ -1498,7 +1498,7 @@ static int gtp_newlink(struct net_device *dev,
 	gtp->restart_count = nla_get_u8_default(data[IFLA_GTP_RESTART_COUNT],
 						0);
 
-	gtp->net = src_net;
+	gtp->net = link_net;
 
 	err = gtp_hashtable_new(gtp, hashsize);
 	if (err < 0)
@@ -1528,7 +1528,7 @@ static int gtp_newlink(struct net_device *dev,
 		goto out_encap;
 	}
 
-	gn = net_generic(src_net, gtp_net_id);
+	gn = net_generic(link_net, gtp_net_id);
 	list_add(&gtp->list, &gn->gtp_dev_list);
 	dev->priv_destructor = gtp_destructor;
 
diff --git a/drivers/net/ipvlan/ipvlan_main.c b/drivers/net/ipvlan/ipvlan_main.c
index 19ce19ca7e32..b56144ca2fde 100644
--- a/drivers/net/ipvlan/ipvlan_main.c
+++ b/drivers/net/ipvlan/ipvlan_main.c
@@ -535,9 +535,9 @@ static int ipvlan_nl_fillinfo(struct sk_buff *skb,
 int ipvlan_link_new(struct net_device *dev, struct rtnl_newlink_params *params,
 		    struct netlink_ext_ack *extack)
 {
+	struct net *link_net = rtnl_newlink_link_net(params);
 	struct ipvl_dev *ipvlan = netdev_priv(dev);
 	struct nlattr **data = params->data;
-	struct net *src_net = params->net;
 	struct nlattr **tb = params->tb;
 	struct ipvl_port *port;
 	struct net_device *phy_dev;
@@ -547,7 +547,7 @@ int ipvlan_link_new(struct net_device *dev, struct rtnl_newlink_params *params,
 	if (!tb[IFLA_LINK])
 		return -EINVAL;
 
-	phy_dev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
+	phy_dev = __dev_get_by_index(link_net, nla_get_u32(tb[IFLA_LINK]));
 	if (!phy_dev)
 		return -ENODEV;
 
diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c
index 1869b0513f57..4de5d63fd577 100644
--- a/drivers/net/macsec.c
+++ b/drivers/net/macsec.c
@@ -4145,10 +4145,10 @@ static int macsec_newlink(struct net_device *dev,
 			  struct rtnl_newlink_params *params,
 			  struct netlink_ext_ack *extack)
 {
+	struct net *link_net = rtnl_newlink_link_net(params);
 	struct macsec_dev *macsec = macsec_priv(dev);
 	struct nlattr **data = params->data;
 	struct nlattr **tb = params->tb;
-	struct net *net = params->net;
 	rx_handler_func_t *rx_handler;
 	u8 icv_len = MACSEC_DEFAULT_ICV_LEN;
 	struct net_device *real_dev;
@@ -4157,7 +4157,7 @@ static int macsec_newlink(struct net_device *dev,
 
 	if (!tb[IFLA_LINK])
 		return -EINVAL;
-	real_dev = __dev_get_by_index(net, nla_get_u32(tb[IFLA_LINK]));
+	real_dev = __dev_get_by_index(link_net, nla_get_u32(tb[IFLA_LINK]));
 	if (!real_dev)
 		return -ENODEV;
 	if (real_dev->type != ARPHRD_ETHER)
diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index f903b414eaeb..4e9d54be887c 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -1444,9 +1444,9 @@ int macvlan_common_newlink(struct net_device *dev,
 			   struct rtnl_newlink_params *params,
 			   struct netlink_ext_ack *extack)
 {
+	struct net *link_net = rtnl_newlink_link_net(params);
 	struct macvlan_dev *vlan = netdev_priv(dev);
 	struct nlattr **data = params->data;
-	struct net *src_net = params->net;
 	struct nlattr **tb = params->tb;
 	struct net_device *lowerdev;
 	struct macvlan_port *port;
@@ -1457,7 +1457,7 @@ int macvlan_common_newlink(struct net_device *dev,
 	if (!tb[IFLA_LINK])
 		return -EINVAL;
 
-	lowerdev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
+	lowerdev = __dev_get_by_index(link_net, nla_get_u32(tb[IFLA_LINK]));
 	if (lowerdev == NULL)
 		return -ENODEV;
 
diff --git a/drivers/net/netkit.c b/drivers/net/netkit.c
index 640a2dbbbd28..751347392570 100644
--- a/drivers/net/netkit.c
+++ b/drivers/net/netkit.c
@@ -331,13 +331,13 @@ static int netkit_new_link(struct net_device *dev,
 			   struct rtnl_newlink_params *params,
 			   struct netlink_ext_ack *extack)
 {
+	struct net *peer_net = rtnl_newlink_peer_net(params);
 	enum netkit_scrub scrub_prim = NETKIT_SCRUB_DEFAULT;
 	enum netkit_scrub scrub_peer = NETKIT_SCRUB_DEFAULT;
 	struct nlattr *peer_tb[IFLA_MAX + 1], **tbp, *attr;
 	enum netkit_action policy_prim = NETKIT_PASS;
 	enum netkit_action policy_peer = NETKIT_PASS;
 	struct nlattr **data = params->data;
-	struct net *peer_net = params->net;
 	enum netkit_mode mode = NETKIT_L3;
 	unsigned char ifname_assign_type;
 	struct nlattr **tb = params->tb;
diff --git a/drivers/net/pfcp.c b/drivers/net/pfcp.c
index 7b0575940e1d..f873a92d2445 100644
--- a/drivers/net/pfcp.c
+++ b/drivers/net/pfcp.c
@@ -188,12 +188,12 @@ static int pfcp_newlink(struct net_device *dev,
 			struct rtnl_newlink_params *params,
 			struct netlink_ext_ack *extack)
 {
+	struct net *link_net = rtnl_newlink_link_net(params);
 	struct pfcp_dev *pfcp = netdev_priv(dev);
-	struct net *net = params->net;
 	struct pfcp_net *pn;
 	int err;
 
-	pfcp->net = net;
+	pfcp->net = link_net;
 
 	err = pfcp_add_sock(pfcp);
 	if (err) {
@@ -207,7 +207,7 @@ static int pfcp_newlink(struct net_device *dev,
 		goto exit_del_pfcp_sock;
 	}
 
-	pn = net_generic(net, pfcp_net_id);
+	pn = net_generic(link_net, pfcp_net_id);
 	list_add(&pfcp->list, &pn->pfcp_dev_list);
 
 	netdev_dbg(dev, "registered new PFCP interface\n");
diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c
index b3340f8a6149..6220866258fc 100644
--- a/drivers/net/ppp/ppp_generic.c
+++ b/drivers/net/ppp/ppp_generic.c
@@ -1307,8 +1307,8 @@ static int ppp_nl_newlink(struct net_device *dev,
 			  struct rtnl_newlink_params *params,
 			  struct netlink_ext_ack *extack)
 {
+	struct net *link_net = rtnl_newlink_link_net(params);
 	struct nlattr **data = params->data;
-	struct net *src_net = params->net;
 	struct nlattr **tb = params->tb;
 	struct ppp_config conf = {
 		.unit = -1,
@@ -1346,7 +1346,7 @@ static int ppp_nl_newlink(struct net_device *dev,
 	if (!tb[IFLA_IFNAME] || !nla_len(tb[IFLA_IFNAME]) || !*(char *)nla_data(tb[IFLA_IFNAME]))
 		conf.ifname_is_set = false;
 
-	err = ppp_dev_configure(src_net, dev, &conf);
+	err = ppp_dev_configure(link_net, dev, &conf);
 
 out_unlock:
 	mutex_unlock(&ppp_mutex);
diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index 7dfda89f072f..ba3ae2d8092f 100644
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c
@@ -1769,8 +1769,8 @@ static int veth_newlink(struct net_device *dev,
 			struct rtnl_newlink_params *params,
 			struct netlink_ext_ack *extack)
 {
+	struct net *peer_net = rtnl_newlink_peer_net(params);
 	struct nlattr **data = params->data;
-	struct net *peer_net = params->net;
 	struct nlattr **tb = params->tb;
 	int err;
 	struct net_device *peer;
diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c
index 09a4a5bf1038..f1212a9256f6 100644
--- a/drivers/net/vxlan/vxlan_core.c
+++ b/drivers/net/vxlan/vxlan_core.c
@@ -4404,8 +4404,8 @@ static int vxlan_newlink(struct net_device *dev,
 			 struct rtnl_newlink_params *params,
 			 struct netlink_ext_ack *extack)
 {
+	struct net *link_net = rtnl_newlink_link_net(params);
 	struct nlattr **data = params->data;
-	struct net *src_net = params->net;
 	struct nlattr **tb = params->tb;
 	struct vxlan_config conf;
 	int err;
@@ -4414,7 +4414,7 @@ static int vxlan_newlink(struct net_device *dev,
 	if (err)
 		return err;
 
-	return __vxlan_dev_create(src_net, dev, &conf, extack);
+	return __vxlan_dev_create(link_net, dev, &conf, extack);
 }
 
 static int vxlan_changelink(struct net_device *dev, struct nlattr *tb[],
diff --git a/drivers/net/wireguard/device.c b/drivers/net/wireguard/device.c
index 404cf05bd72b..c496d35b266d 100644
--- a/drivers/net/wireguard/device.c
+++ b/drivers/net/wireguard/device.c
@@ -311,11 +311,11 @@ static int wg_newlink(struct net_device *dev,
 		      struct rtnl_newlink_params *params,
 		      struct netlink_ext_ack *extack)
 {
+	struct net *link_net = rtnl_newlink_link_net(params);
 	struct wg_device *wg = netdev_priv(dev);
-	struct net *src_net = params->net;
 	int ret = -ENOMEM;
 
-	rcu_assign_pointer(wg->creating_net, src_net);
+	rcu_assign_pointer(wg->creating_net, link_net);
 	init_rwsem(&wg->static_identity.lock);
 	mutex_init(&wg->socket_update_lock);
 	mutex_init(&wg->device_update_lock);
diff --git a/drivers/net/wireless/virtual/virt_wifi.c b/drivers/net/wireless/virtual/virt_wifi.c
index 26905b2b3ba3..f9d11a023313 100644
--- a/drivers/net/wireless/virtual/virt_wifi.c
+++ b/drivers/net/wireless/virtual/virt_wifi.c
@@ -524,7 +524,7 @@ static int virt_wifi_newlink(struct net_device *dev,
 			     struct netlink_ext_ack *extack)
 {
 	struct virt_wifi_netdev_priv *priv = netdev_priv(dev);
-	struct net *src_net = params->net;
+	struct net *link_net = rtnl_newlink_link_net(params);
 	struct nlattr **tb = params->tb;
 	int err;
 
@@ -534,7 +534,7 @@ static int virt_wifi_newlink(struct net_device *dev,
 	netif_carrier_off(dev);
 
 	priv->upperdev = dev;
-	priv->lowerdev = __dev_get_by_index(src_net,
+	priv->lowerdev = __dev_get_by_index(link_net,
 					    nla_get_u32(tb[IFLA_LINK]));
 
 	if (!priv->lowerdev)
diff --git a/drivers/net/wwan/wwan_core.c b/drivers/net/wwan/wwan_core.c
index a05c49b4e7f8..63a47d420bc5 100644
--- a/drivers/net/wwan/wwan_core.c
+++ b/drivers/net/wwan/wwan_core.c
@@ -1065,7 +1065,7 @@ static void wwan_create_default_link(struct wwan_device *wwandev,
 	struct nlattr *tb[IFLA_MAX + 1], *linkinfo[IFLA_INFO_MAX + 1];
 	struct nlattr *data[IFLA_WWAN_MAX + 1];
 	struct rtnl_newlink_params params = {
-		.net = &init_net,
+		.src_net = &init_net,
 		.tb = tb,
 		.data = data,
 	};
diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h
index 563a6a27436c..b22a106621fb 100644
--- a/include/net/rtnetlink.h
+++ b/include/net/rtnetlink.h
@@ -88,6 +88,23 @@ struct rtnl_newlink_params {
 	struct nlattr **data;
 };
 
+/* Get effective link netns from newlink params. Generally, this is link_net
+ * and falls back to src_net. But for compatibility, a driver may * choose to
+ * use dev_net(dev) instead.
+ */
+static inline struct net *rtnl_newlink_link_net(struct rtnl_newlink_params *p)
+{
+	return p->link_net ? : p->src_net;
+}
+
+/* Get peer netns from newlink params. Fallback to link netns if peer netns is
+ * not specified explicitly.
+ */
+static inline struct net *rtnl_newlink_peer_net(struct rtnl_newlink_params *p)
+{
+	return p->peer_net ? : rtnl_newlink_link_net(p);
+}
+
 /**
  *	struct rtnl_link_ops - rtnetlink link operations
  *
diff --git a/net/8021q/vlan_netlink.c b/net/8021q/vlan_netlink.c
index 91df0f96e32a..a000b1ef0520 100644
--- a/net/8021q/vlan_netlink.c
+++ b/net/8021q/vlan_netlink.c
@@ -139,9 +139,9 @@ static int vlan_newlink(struct net_device *dev,
 			struct rtnl_newlink_params *params,
 			struct netlink_ext_ack *extack)
 {
+	struct net *link_net = rtnl_newlink_link_net(params);
 	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
 	struct nlattr **data = params->data;
-	struct net *src_net = params->net;
 	struct nlattr **tb = params->tb;
 	struct net_device *real_dev;
 	unsigned int max_mtu;
@@ -158,7 +158,7 @@ static int vlan_newlink(struct net_device *dev,
 		return -EINVAL;
 	}
 
-	real_dev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
+	real_dev = __dev_get_by_index(link_net, nla_get_u32(tb[IFLA_LINK]));
 	if (!real_dev) {
 		NL_SET_ERR_MSG_MOD(extack, "link does not exist");
 		return -ENODEV;
diff --git a/net/hsr/hsr_netlink.c b/net/hsr/hsr_netlink.c
index 39add538ba99..b120470246cc 100644
--- a/net/hsr/hsr_netlink.c
+++ b/net/hsr/hsr_netlink.c
@@ -33,8 +33,8 @@ static int hsr_newlink(struct net_device *dev,
 		       struct rtnl_newlink_params *params,
 		       struct netlink_ext_ack *extack)
 {
+	struct net *link_net = rtnl_newlink_link_net(params);
 	struct nlattr **data = params->data;
-	struct net *src_net = params->net;
 	enum hsr_version proto_version;
 	unsigned char multicast_spec;
 	u8 proto = HSR_PROTOCOL_HSR;
@@ -48,7 +48,7 @@ static int hsr_newlink(struct net_device *dev,
 		NL_SET_ERR_MSG_MOD(extack, "Slave1 device not specified");
 		return -EINVAL;
 	}
-	link[0] = __dev_get_by_index(src_net,
+	link[0] = __dev_get_by_index(link_net,
 				     nla_get_u32(data[IFLA_HSR_SLAVE1]));
 	if (!link[0]) {
 		NL_SET_ERR_MSG_MOD(extack, "Slave1 does not exist");
@@ -58,7 +58,7 @@ static int hsr_newlink(struct net_device *dev,
 		NL_SET_ERR_MSG_MOD(extack, "Slave2 device not specified");
 		return -EINVAL;
 	}
-	link[1] = __dev_get_by_index(src_net,
+	link[1] = __dev_get_by_index(link_net,
 				     nla_get_u32(data[IFLA_HSR_SLAVE2]));
 	if (!link[1]) {
 		NL_SET_ERR_MSG_MOD(extack, "Slave2 does not exist");
@@ -71,7 +71,7 @@ static int hsr_newlink(struct net_device *dev,
 	}
 
 	if (data[IFLA_HSR_INTERLINK])
-		interlink = __dev_get_by_index(src_net,
+		interlink = __dev_get_by_index(link_net,
 					       nla_get_u32(data[IFLA_HSR_INTERLINK]));
 
 	if (interlink && interlink == link[0]) {
-- 
2.48.1

[PATCH net-next v10 04/13] ieee802154: 6lowpan: Validate link netns in newlink() of rtnl_link_ops

[Xiao Liang]

Device denoted by IFLA_LINK is in link_net (IFLA_LINK_NETNSID) or
source netns by design, but 6lowpan uses dev_net.

Note dev->netns_local is set to true and currently link_net is
implemented via a netns change. These together effectively reject
IFLA_LINK_NETNSID.

This patch adds a validation to ensure link_net is either NULL or
identical to dev_net. Thus it would be fine to continue using dev_net
when rtnetlink core begins to create devices directly in target netns.

Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
---
 net/ieee802154/6lowpan/core.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/ieee802154/6lowpan/core.c b/net/ieee802154/6lowpan/core.c
index 704bf9e3f097..ee318d46817d 100644
--- a/net/ieee802154/6lowpan/core.c
+++ b/net/ieee802154/6lowpan/core.c
@@ -143,6 +143,8 @@ static int lowpan_newlink(struct net_device *ldev,
 
 	if (!tb[IFLA_LINK])
 		return -EINVAL;
+	if (params->link_net && !net_eq(params->link_net, dev_net(ldev)))
+		return -EINVAL;
 	/* find and hold wpan device */
 	wdev = dev_get_by_index(dev_net(ldev), nla_get_u32(tb[IFLA_LINK]));
 	if (!wdev)
-- 
2.48.1

[PATCH net-next v10 05/13] net: ip_tunnel: Don't set tunnel->net in ip_tunnel_init()

[Xiao Liang]

ip_tunnel_init() is called from register_netdevice(). In all code paths
reaching here, tunnel->net should already have been set (either in
ip_tunnel_newlink() or __ip_tunnel_create()). So don't set it again.

Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
---
 net/ipv4/ip_tunnel.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index 09b73acf037a..dd4b4e5be998 100644
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -1326,7 +1326,6 @@ int ip_tunnel_init(struct net_device *dev)
 	}
 
 	tunnel->dev = dev;
-	tunnel->net = dev_net(dev);
 	strscpy(tunnel->parms.name, dev->name);
 	iph->version		= 4;
 	iph->ihl		= 5;
-- 
2.48.1

Re: [PATCH net-next v10 05/13] net: ip_tunnel: Don't set tunnel->net in ip_tunnel_init()

[Kuniyuki Iwashima]

From: Xiao Liang <shaw.leon@gmail.com>
Date: Wed, 19 Feb 2025 20:50:31 +0800
> ip_tunnel_init() is called from register_netdevice(). In all code paths
> reaching here, tunnel->net should already have been set (either in
> ip_tunnel_newlink() or __ip_tunnel_create()). So don't set it again.
> 
> Signed-off-by: Xiao Liang <shaw.leon@gmail.com>

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>

[PATCH net-next v10 06/13] net: ip_tunnel: Use link netns in newlink() of rtnl_link_ops

[Xiao Liang]

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.

Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
---
 include/net/ip_tunnels.h | 5 +++--
 net/ipv4/ip_gre.c        | 8 +++++---
 net/ipv4/ip_tunnel.c     | 6 +++---
 net/ipv4/ip_vti.c        | 3 ++-
 net/ipv4/ipip.c          | 3 ++-
 5 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h
index 1aa31bdb2b31..ae1f2dda4533 100644
--- a/include/net/ip_tunnels.h
+++ b/include/net/ip_tunnels.h
@@ -406,8 +406,9 @@ int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
 		  bool log_ecn_error);
 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
 			 struct ip_tunnel_parm_kern *p, __u32 fwmark);
-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);
 void ip_tunnel_setup(struct net_device *dev, unsigned int net_id);
 
 bool ip_tunnel_netlink_encap_parms(struct nlattr *data[],
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,
+				 fwmark);
 }
 
 static int erspan_newlink(struct net_device *dev,
@@ -1433,7 +1434,8 @@ static int erspan_newlink(struct net_device *dev,
 	err = erspan_netlink_parms(dev, data, tb, &p, &fwmark);
 	if (err)
 		return err;
-	return ip_tunnel_newlink(dev, tb, &p, fwmark);
+	return ip_tunnel_newlink(params->link_net ? : dev_net(dev), dev, tb, &p,
+				 fwmark);
 }
 
 static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[],
@@ -1701,7 +1703,7 @@ static struct rtnl_link_ops erspan_link_ops __read_mostly = {
 struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
 					u8 name_assign_type)
 {
-	struct rtnl_newlink_params params = { .net = net };
+	struct rtnl_newlink_params params = { .src_net = net };
 	struct nlattr *tb[IFLA_MAX + 1];
 	struct net_device *dev;
 	LIST_HEAD(list_kill);
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index dd4b4e5be998..011f2a5aab3b 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;
diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c
index b901bee03e6d..159b4473290e 100644
--- a/net/ipv4/ip_vti.c
+++ b/net/ipv4/ip_vti.c
@@ -585,7 +585,8 @@ static int vti_newlink(struct net_device *dev,
 	__u32 fwmark = 0;
 
 	vti_netlink_parms(data, &parms, &fwmark);
-	return ip_tunnel_newlink(dev, tb, &parms, fwmark);
+	return ip_tunnel_newlink(params->link_net ? : dev_net(dev), dev, tb,
+				 &parms, fwmark);
 }
 
 static int vti_changelink(struct net_device *dev, struct nlattr *tb[],
diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c
index a8b844bcfc64..bab0bf90c908 100644
--- a/net/ipv4/ipip.c
+++ b/net/ipv4/ipip.c
@@ -455,7 +455,8 @@ static int ipip_newlink(struct net_device *dev,
 	}
 
 	ipip_netlink_parms(data, &p, &t->collect_md, &fwmark);
-	return ip_tunnel_newlink(dev, tb, &p, fwmark);
+	return ip_tunnel_newlink(params->link_net ? : dev_net(dev), dev, tb, &p,
+				 fwmark);
 }
 
 static int ipip_changelink(struct net_device *dev, struct nlattr *tb[],
-- 
2.48.1

Re: [PATCH net-next v10 06/13] net: ip_tunnel: Use link netns in newlink() of rtnl_link_ops

[Kuniyuki Iwashima]

From: Xiao Liang <shaw.leon@gmail.com>
Date: Wed, 19 Feb 2025 20:50:32 +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.
> 
> Signed-off-by: Xiao Liang <shaw.leon@gmail.com>

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>

[PATCH net-next v10 07/13] net: ipv6: Init tunnel link-netns before registering dev

[Xiao Liang]

Currently some IPv6 tunnel drivers set tnl->net to dev_net(dev) in
ndo_init(), which is called in register_netdevice(). However, it lacks
the context of link-netns when we enable cross-net tunnels at device
registration time.

Let's move the init of tunnel link-netns before register_netdevice().

ip6_gre has already initialized netns, so just remove the redundant
assignment.

Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
---
 net/ipv6/ip6_gre.c    | 2 --
 net/ipv6/ip6_tunnel.c | 3 ++-
 net/ipv6/ip6_vti.c    | 3 ++-
 net/ipv6/sit.c        | 8 +++++---
 4 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index 863852abe8ea..d9e6b1fd9917 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -1498,7 +1498,6 @@ static int ip6gre_tunnel_init_common(struct net_device *dev)
 	tunnel = netdev_priv(dev);
 
 	tunnel->dev = dev;
-	tunnel->net = dev_net(dev);
 	strcpy(tunnel->parms.name, dev->name);
 
 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
@@ -1882,7 +1881,6 @@ static int ip6erspan_tap_init(struct net_device *dev)
 	tunnel = netdev_priv(dev);
 
 	tunnel->dev = dev;
-	tunnel->net = dev_net(dev);
 	strcpy(tunnel->parms.name, dev->name);
 
 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 54b843d20870..111a8777c2f7 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -1878,7 +1878,6 @@ ip6_tnl_dev_init_gen(struct net_device *dev)
 	int t_hlen;
 
 	t->dev = dev;
-	t->net = dev_net(dev);
 
 	ret = dst_cache_init(&t->dst_cache, GFP_KERNEL);
 	if (ret)
@@ -1940,6 +1939,7 @@ static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
 	struct net *net = dev_net(dev);
 	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 
+	t->net = net;
 	t->parms.proto = IPPROTO_IPV6;
 
 	rcu_assign_pointer(ip6n->tnls_wc[0], t);
@@ -2015,6 +2015,7 @@ static int ip6_tnl_newlink(struct net_device *dev,
 	int err;
 
 	nt = netdev_priv(dev);
+	nt->net = net;
 
 	if (ip_tunnel_netlink_encap_parms(data, &ipencap)) {
 		err = ip6_tnl_encap_setup(nt, &ipencap);
diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c
index 993f85aeb882..16e0d74f99dd 100644
--- a/net/ipv6/ip6_vti.c
+++ b/net/ipv6/ip6_vti.c
@@ -925,7 +925,6 @@ static inline int vti6_dev_init_gen(struct net_device *dev)
 	struct ip6_tnl *t = netdev_priv(dev);
 
 	t->dev = dev;
-	t->net = dev_net(dev);
 	netdev_hold(dev, &t->dev_tracker, GFP_KERNEL);
 	netdev_lockdep_set_classes(dev);
 	return 0;
@@ -958,6 +957,7 @@ static int __net_init vti6_fb_tnl_dev_init(struct net_device *dev)
 	struct net *net = dev_net(dev);
 	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
 
+	t->net = net;
 	t->parms.proto = IPPROTO_IPV6;
 
 	rcu_assign_pointer(ip6n->tnls_wc[0], t);
@@ -1009,6 +1009,7 @@ static int vti6_newlink(struct net_device *dev,
 	vti6_netlink_parms(data, &nt->parms);
 
 	nt->parms.proto = IPPROTO_IPV6;
+	nt->net = net;
 
 	if (vti6_locate(net, &nt->parms, 0))
 		return -EEXIST;
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index e2bd52cabdee..20453671ac50 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -269,6 +269,7 @@ static struct ip_tunnel *ipip6_tunnel_locate(struct net *net,
 
 	nt = netdev_priv(dev);
 
+	nt->net = net;
 	nt->parms = *parms;
 	if (ipip6_tunnel_create(dev) < 0)
 		goto failed_free;
@@ -1449,7 +1450,6 @@ static int ipip6_tunnel_init(struct net_device *dev)
 	int err;
 
 	tunnel->dev = dev;
-	tunnel->net = dev_net(dev);
 	strcpy(tunnel->parms.name, dev->name);
 
 	ipip6_tunnel_bind_dev(dev);
@@ -1565,6 +1565,7 @@ static int ipip6_newlink(struct net_device *dev,
 	int err;
 
 	nt = netdev_priv(dev);
+	nt->net = net;
 
 	if (ip_tunnel_netlink_encap_parms(data, &ipencap)) {
 		err = ip_tunnel_encap_setup(nt, &ipencap);
@@ -1860,6 +1861,9 @@ static int __net_init sit_init_net(struct net *net)
 	 */
 	sitn->fb_tunnel_dev->netns_local = true;
 
+	t = netdev_priv(sitn->fb_tunnel_dev);
+	t->net = net;
+
 	err = register_netdev(sitn->fb_tunnel_dev);
 	if (err)
 		goto err_reg_dev;
@@ -1867,8 +1871,6 @@ static int __net_init sit_init_net(struct net *net)
 	ipip6_tunnel_clone_6rd(sitn->fb_tunnel_dev, sitn);
 	ipip6_fb_tunnel_init(sitn->fb_tunnel_dev);
 
-	t = netdev_priv(sitn->fb_tunnel_dev);
-
 	strcpy(t->parms.name, sitn->fb_tunnel_dev->name);
 	return 0;
 
-- 
2.48.1

Re: [PATCH net-next v10 07/13] net: ipv6: Init tunnel link-netns before registering dev

[Kuniyuki Iwashima]

From: Xiao Liang <shaw.leon@gmail.com>
Date: Wed, 19 Feb 2025 20:50:33 +0800
> Currently some IPv6 tunnel drivers set tnl->net to dev_net(dev) in
> ndo_init(), which is called in register_netdevice(). However, it lacks
> the context of link-netns when we enable cross-net tunnels at device
> registration time.
> 
> Let's move the init of tunnel link-netns before register_netdevice().
> 
> ip6_gre has already initialized netns, so just remove the redundant
> assignment.
> 
> Signed-off-by: Xiao Liang <shaw.leon@gmail.com>

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>

left a small comment, but not a blocker.


> @@ -1565,6 +1565,7 @@ static int ipip6_newlink(struct net_device *dev,
>  	int err;
>  
>  	nt = netdev_priv(dev);
> +	nt->net = net;

This hunk is not necessary as we'll call ipip6_tunnel_locate(),
but it's harmless and not worth reposting the whole series given
we are alredy in v10.  You can just post a follow-up patch after
the series is applied.

Thanks!

[PATCH net-next v10 08/13] net: ipv6: Use link netns in newlink() of rtnl_link_ops

[Xiao Liang]

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.

Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
---
 net/ipv6/ip6_gre.c    | 14 ++++++--------
 net/ipv6/ip6_tunnel.c |  9 +++++----
 net/ipv6/ip6_vti.c    |  6 +++---
 net/ipv6/sit.c        |  6 +++---
 4 files changed, 17 insertions(+), 18 deletions(-)

diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index d9e6b1fd9917..d31a4ce3b19f 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -1969,7 +1969,7 @@ static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
 	return ret;
 }
 
-static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
+static int ip6gre_newlink_common(struct net *link_net, struct net_device *dev,
 				 struct nlattr *tb[], struct nlattr *data[],
 				 struct netlink_ext_ack *extack)
 {
@@ -1990,7 +1990,7 @@ static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
 		eth_hw_addr_random(dev);
 
 	nt->dev = dev;
-	nt->net = dev_net(dev);
+	nt->net = link_net;
 
 	err = register_netdevice(dev);
 	if (err)
@@ -2007,11 +2007,10 @@ static int ip6gre_newlink(struct net_device *dev,
 			  struct rtnl_newlink_params *params,
 			  struct netlink_ext_ack *extack)
 {
+	struct net *net = params->link_net ? : dev_net(dev);
 	struct ip6_tnl *nt = netdev_priv(dev);
 	struct nlattr **data = params->data;
-	struct net *src_net = params->net;
 	struct nlattr **tb = params->tb;
-	struct net *net = dev_net(dev);
 	struct ip6gre_net *ign;
 	int err;
 
@@ -2026,7 +2025,7 @@ static int ip6gre_newlink(struct net_device *dev,
 			return -EEXIST;
 	}
 
-	err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
+	err = ip6gre_newlink_common(net, dev, tb, data, extack);
 	if (!err) {
 		ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
 		ip6gre_tunnel_link_md(ign, nt);
@@ -2246,11 +2245,10 @@ static int ip6erspan_newlink(struct net_device *dev,
 			     struct rtnl_newlink_params *params,
 			     struct netlink_ext_ack *extack)
 {
+	struct net *net = params->link_net ? : dev_net(dev);
 	struct ip6_tnl *nt = netdev_priv(dev);
 	struct nlattr **data = params->data;
-	struct net *src_net = params->net;
 	struct nlattr **tb = params->tb;
-	struct net *net = dev_net(dev);
 	struct ip6gre_net *ign;
 	int err;
 
@@ -2266,7 +2264,7 @@ static int ip6erspan_newlink(struct net_device *dev,
 			return -EEXIST;
 	}
 
-	err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
+	err = ip6gre_newlink_common(net, dev, tb, data, extack);
 	if (!err) {
 		ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
 		ip6erspan_tunnel_link_md(ign, nt);
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 111a8777c2f7..89d206731af0 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -253,8 +253,7 @@ static void ip6_dev_free(struct net_device *dev)
 static int ip6_tnl_create2(struct net_device *dev)
 {
 	struct ip6_tnl *t = netdev_priv(dev);
-	struct net *net = dev_net(dev);
-	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
+	struct ip6_tnl_net *ip6n = net_generic(t->net, ip6_tnl_net_id);
 	int err;
 
 	dev->rtnl_link_ops = &ip6_link_ops;
@@ -2008,12 +2007,14 @@ static int ip6_tnl_newlink(struct net_device *dev,
 {
 	struct nlattr **data = params->data;
 	struct nlattr **tb = params->tb;
-	struct net *net = dev_net(dev);
-	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 	struct ip_tunnel_encap ipencap;
+	struct ip6_tnl_net *ip6n;
 	struct ip6_tnl *nt, *t;
+	struct net *net;
 	int err;
 
+	net = params->link_net ? : dev_net(dev);
+	ip6n = net_generic(net, ip6_tnl_net_id);
 	nt = netdev_priv(dev);
 	nt->net = net;
 
diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c
index 16e0d74f99dd..83c055996fbb 100644
--- a/net/ipv6/ip6_vti.c
+++ b/net/ipv6/ip6_vti.c
@@ -177,8 +177,7 @@ vti6_tnl_unlink(struct vti6_net *ip6n, struct ip6_tnl *t)
 static int vti6_tnl_create2(struct net_device *dev)
 {
 	struct ip6_tnl *t = netdev_priv(dev);
-	struct net *net = dev_net(dev);
-	struct vti6_net *ip6n = net_generic(net, vti6_net_id);
+	struct vti6_net *ip6n = net_generic(t->net, vti6_net_id);
 	int err;
 
 	dev->rtnl_link_ops = &vti6_link_ops;
@@ -1002,9 +1001,10 @@ static int vti6_newlink(struct net_device *dev,
 			struct netlink_ext_ack *extack)
 {
 	struct nlattr **data = params->data;
-	struct net *net = dev_net(dev);
 	struct ip6_tnl *nt;
+	struct net *net;
 
+	net = params->link_net ? : dev_net(dev);
 	nt = netdev_priv(dev);
 	vti6_netlink_parms(data, &nt->parms);
 
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 20453671ac50..f7b59bc957d3 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -201,8 +201,7 @@ static void ipip6_tunnel_clone_6rd(struct net_device *dev, struct sit_net *sitn)
 static int ipip6_tunnel_create(struct net_device *dev)
 {
 	struct ip_tunnel *t = netdev_priv(dev);
-	struct net *net = dev_net(dev);
-	struct sit_net *sitn = net_generic(net, sit_net_id);
+	struct sit_net *sitn = net_generic(t->net, sit_net_id);
 	int err;
 
 	__dev_addr_set(dev, &t->parms.iph.saddr, 4);
@@ -1556,14 +1555,15 @@ static int ipip6_newlink(struct net_device *dev,
 {
 	struct nlattr **data = params->data;
 	struct nlattr **tb = params->tb;
-	struct net *net = dev_net(dev);
 	struct ip_tunnel *nt;
 	struct ip_tunnel_encap ipencap;
 #ifdef CONFIG_IPV6_SIT_6RD
 	struct ip_tunnel_6rd ip6rd;
 #endif
+	struct net *net;
 	int err;
 
+	net = params->link_net ? : dev_net(dev);
 	nt = netdev_priv(dev);
 	nt->net = net;
 
-- 
2.48.1

Re: [PATCH net-next v10 08/13] net: ipv6: Use link netns in newlink() of rtnl_link_ops

[Kuniyuki Iwashima]

From: Xiao Liang <shaw.leon@gmail.com>
Date: Wed, 19 Feb 2025 20:50:34 +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.
> 
> Signed-off-by: Xiao Liang <shaw.leon@gmail.com>

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>

[PATCH net-next v10 09/13] net: xfrm: Use link netns in newlink() of rtnl_link_ops

[Xiao Liang]

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.

Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
---
 net/xfrm/xfrm_interface_core.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/xfrm/xfrm_interface_core.c b/net/xfrm/xfrm_interface_core.c
index 5659a6cadd51..622445f041d3 100644
--- a/net/xfrm/xfrm_interface_core.c
+++ b/net/xfrm/xfrm_interface_core.c
@@ -242,10 +242,9 @@ static void xfrmi_dev_free(struct net_device *dev)
 	gro_cells_destroy(&xi->gro_cells);
 }
 
-static int xfrmi_create(struct net_device *dev)
+static int xfrmi_create(struct net *net, struct net_device *dev)
 {
 	struct xfrm_if *xi = netdev_priv(dev);
-	struct net *net = dev_net(dev);
 	struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
 	int err;
 
@@ -819,11 +818,12 @@ static int xfrmi_newlink(struct net_device *dev,
 			 struct netlink_ext_ack *extack)
 {
 	struct nlattr **data = params->data;
-	struct net *net = dev_net(dev);
 	struct xfrm_if_parms p = {};
 	struct xfrm_if *xi;
+	struct net *net;
 	int err;
 
+	net = params->link_net ? : dev_net(dev);
 	xfrmi_netlink_parms(data, &p);
 	if (p.collect_md) {
 		struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
@@ -852,7 +852,7 @@ static int xfrmi_newlink(struct net_device *dev,
 	xi->net = net;
 	xi->dev = dev;
 
-	err = xfrmi_create(dev);
+	err = xfrmi_create(net, dev);
 	return err;
 }
 
-- 
2.48.1

[PATCH net-next v10 10/13] rtnetlink: Remove "net" from newlink params

[Xiao Liang]

Now that devices have been converted to use the specific netns instead
of ambiguous "net", let's remove it from newlink parameters.

Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
---
 include/net/rtnetlink.h | 2 --
 net/core/rtnetlink.c    | 6 ------
 2 files changed, 8 deletions(-)

diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h
index b22a106621fb..ec65a8cebb99 100644
--- a/include/net/rtnetlink.h
+++ b/include/net/rtnetlink.h
@@ -72,7 +72,6 @@ static inline int rtnl_msg_family(const struct nlmsghdr *nlh)
 /**
  * struct rtnl_newlink_params - parameters of rtnl_link_ops::newlink()
  *
- * @net: Netns of interest
  * @src_net: Source netns of rtnetlink socket
  * @link_net: Link netns by IFLA_LINK_NETNSID, NULL if not specified
  * @peer_net: Peer netns
@@ -80,7 +79,6 @@ static inline int rtnl_msg_family(const struct nlmsghdr *nlh)
  * @data: IFLA_INFO_DATA attributes
  */
 struct rtnl_newlink_params {
-	struct net *net;
 	struct net *src_net;
 	struct net *link_net;
 	struct net *peer_net;
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 9ebbde0d131c..e980481bdd28 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -3798,12 +3798,6 @@ static int rtnl_newlink_create(struct sk_buff *skb, struct ifinfomsg *ifm,
 
 	dev->ifindex = ifm->ifi_index;
 
-	params.net = params.src_net;
-	if (link_net)
-		params.net = link_net;
-	if (peer_net)
-		params.net = peer_net;
-
 	if (ops->newlink)
 		err = ops->newlink(dev, &params, extack);
 	else
-- 
2.48.1

Re: [PATCH net-next v10 10/13] rtnetlink: Remove "net" from newlink params

[Kuniyuki Iwashima]

From: Xiao Liang <shaw.leon@gmail.com>
Date: Wed, 19 Feb 2025 20:50:36 +0800
> Now that devices have been converted to use the specific netns instead
> of ambiguous "net", let's remove it from newlink parameters.
> 
> Signed-off-by: Xiao Liang <shaw.leon@gmail.com>

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>

[PATCH net-next v10 11/13] rtnetlink: Create link directly in target net namespace

[Xiao Liang]

Make rtnl_newlink_create() create device in target namespace directly.
Avoid extra netns change when link netns is provided.

Device drivers has been converted to be aware of link netns, that is not
assuming device netns is and link netns is the same when ops->newlink()
is called.

Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
---
 net/core/rtnetlink.c | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index e980481bdd28..b52e610e157e 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -3789,8 +3789,8 @@ static int rtnl_newlink_create(struct sk_buff *skb, struct ifinfomsg *ifm,
 		name_assign_type = NET_NAME_ENUM;
 	}
 
-	dev = rtnl_create_link(link_net ? : tgt_net, ifname,
-			       name_assign_type, ops, tb, extack);
+	dev = rtnl_create_link(tgt_net, ifname, name_assign_type, ops, tb,
+			       extack);
 	if (IS_ERR(dev)) {
 		err = PTR_ERR(dev);
 		goto out;
@@ -3810,11 +3810,6 @@ static int rtnl_newlink_create(struct sk_buff *skb, struct ifinfomsg *ifm,
 	err = rtnl_configure_link(dev, ifm, portid, nlh);
 	if (err < 0)
 		goto out_unregister;
-	if (link_net) {
-		err = dev_change_net_namespace(dev, tgt_net, ifname);
-		if (err < 0)
-			goto out_unregister;
-	}
 	if (tb[IFLA_MASTER]) {
 		err = do_set_master(dev, nla_get_u32(tb[IFLA_MASTER]), extack);
 		if (err)
-- 
2.48.1

[PATCH net-next v10 13/13] selftests: net: Add test cases for link and peer netns

[Xiao Liang]

 - Add test for creating link in another netns when a link of the same
   name and ifindex exists in current netns.
 - Add test to verify that link is created in target netns directly -
   no link new/del events should be generated in link netns or current
   netns.
 - Add test cases to verify that link-netns is set as expected for
   various drivers and combination of namespace-related parameters.

Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
---
 tools/testing/selftests/net/Makefile      |   1 +
 tools/testing/selftests/net/config        |   5 +
 tools/testing/selftests/net/link_netns.py | 141 ++++++++++++++++++++++
 tools/testing/selftests/net/netns-name.sh |  10 ++
 4 files changed, 157 insertions(+)
 create mode 100755 tools/testing/selftests/net/link_netns.py

diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index 8d6116b80cf1..aeb96c085614 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -36,6 +36,7 @@ TEST_PROGS += cmsg_so_priority.sh
 TEST_PROGS += test_so_rcv.sh
 TEST_PROGS += cmsg_time.sh cmsg_ipv6.sh
 TEST_PROGS += netns-name.sh
+TEST_PROGS += link_netns.py
 TEST_PROGS += nl_netdev.py
 TEST_PROGS += rtnetlink.py
 TEST_PROGS += srv6_end_dt46_l3vpn_test.sh
diff --git a/tools/testing/selftests/net/config b/tools/testing/selftests/net/config
index 5b9baf708950..ab55270669ec 100644
--- a/tools/testing/selftests/net/config
+++ b/tools/testing/selftests/net/config
@@ -107,3 +107,8 @@ CONFIG_XFRM_INTERFACE=m
 CONFIG_XFRM_USER=m
 CONFIG_IP_NF_MATCH_RPFILTER=m
 CONFIG_IP6_NF_MATCH_RPFILTER=m
+CONFIG_IPVLAN=m
+CONFIG_CAN=m
+CONFIG_CAN_DEV=m
+CONFIG_CAN_VXCAN=m
+CONFIG_NETKIT=y
diff --git a/tools/testing/selftests/net/link_netns.py b/tools/testing/selftests/net/link_netns.py
new file mode 100755
index 000000000000..aab043c59d69
--- /dev/null
+++ b/tools/testing/selftests/net/link_netns.py
@@ -0,0 +1,141 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+import time
+
+from lib.py import ksft_run, ksft_exit, ksft_true
+from lib.py import ip
+from lib.py import NetNS, NetNSEnter
+from lib.py import RtnlFamily
+
+
+LINK_NETNSID = 100
+
+
+def test_event() -> None:
+    with NetNS() as ns1, NetNS() as ns2:
+        with NetNSEnter(str(ns2)):
+            rtnl = RtnlFamily()
+
+        rtnl.ntf_subscribe("rtnlgrp-link")
+
+        ip(f"netns set {ns2} {LINK_NETNSID}", ns=str(ns1))
+        ip(f"link add netns {ns1} link-netnsid {LINK_NETNSID} dummy1 type dummy")
+        ip(f"link add netns {ns1} dummy2 type dummy", ns=str(ns2))
+
+        ip("link del dummy1", ns=str(ns1))
+        ip("link del dummy2", ns=str(ns1))
+
+        time.sleep(1)
+        rtnl.check_ntf()
+        ksft_true(rtnl.async_msg_queue.empty(),
+                  "Received unexpected link notification")
+
+
+def validate_link_netns(netns, ifname, link_netnsid) -> bool:
+    link_info = ip(f"-d link show dev {ifname}", ns=netns, json=True)
+    if not link_info:
+        return False
+    return link_info[0].get("link_netnsid") == link_netnsid
+
+
+def test_link_net() -> None:
+    configs = [
+        # type, common args, type args, fallback to dev_net
+        ("ipvlan", "link dummy1", "", False),
+        ("macsec", "link dummy1", "", False),
+        ("macvlan", "link dummy1", "", False),
+        ("macvtap", "link dummy1", "", False),
+        ("vlan", "link dummy1", "id 100", False),
+        ("gre", "", "local 192.0.2.1", True),
+        ("vti", "", "local 192.0.2.1", True),
+        ("ipip", "", "local 192.0.2.1", True),
+        ("ip6gre", "", "local 2001:db8::1", True),
+        ("ip6tnl", "", "local 2001:db8::1", True),
+        ("vti6", "", "local 2001:db8::1", True),
+        ("sit", "", "local 192.0.2.1", True),
+        ("xfrm", "", "if_id 1", True),
+    ]
+
+    with NetNS() as ns1, NetNS() as ns2, NetNS() as ns3:
+        net1, net2, net3 = str(ns1), str(ns2), str(ns3)
+
+        # prepare link netnsid  and a dummy link needed by certain drivers
+        ip(f"netns set {net3} {LINK_NETNSID}", ns=str(net2))
+        ip("link add dummy1 type dummy", ns=net3)
+
+        cases = [
+            # source, "netns", "link-netns", expected link-netns
+            (net3, None, None, None, None),
+            (net3, net2, None, None, LINK_NETNSID),
+            (net2, None, net3, LINK_NETNSID, LINK_NETNSID),
+            (net1, net2, net3, LINK_NETNSID, LINK_NETNSID),
+        ]
+
+        for src_net, netns, link_netns, exp1, exp2 in cases:
+            tgt_net = netns or src_net
+            for typ, cargs, targs, fb_dev_net in configs:
+                cmd = "link add"
+                if netns:
+                    cmd += f" netns {netns}"
+                if link_netns:
+                    cmd += f" link-netns {link_netns}"
+                cmd += f" {cargs} foo type {typ} {targs}"
+                ip(cmd, ns=src_net)
+                if fb_dev_net:
+                    ksft_true(validate_link_netns(tgt_net, "foo", exp1),
+                              f"{typ} link_netns validation failed")
+                else:
+                    ksft_true(validate_link_netns(tgt_net, "foo", exp2),
+                              f"{typ} link_netns validation failed")
+                ip(f"link del foo", ns=tgt_net)
+
+
+def test_peer_net() -> None:
+    types = [
+        "vxcan",
+        "netkit",
+        "veth",
+    ]
+
+    with NetNS() as ns1, NetNS() as ns2, NetNS() as ns3, NetNS() as ns4:
+        net1, net2, net3, net4 = str(ns1), str(ns2), str(ns3), str(ns4)
+
+        ip(f"netns set {net3} {LINK_NETNSID}", ns=str(net2))
+
+        cases = [
+            # source, "netns", "link-netns", "peer netns", expected
+            (net1, None, None, None, None),
+            (net1, net2, None, None, None),
+            (net2, None, net3, None, LINK_NETNSID),
+            (net1, net2, net3, None, None),
+            (net2, None, None, net3, LINK_NETNSID),
+            (net1, net2, None, net3, LINK_NETNSID),
+            (net2, None, net2, net3, LINK_NETNSID),
+            (net1, net2, net4, net3, LINK_NETNSID),
+        ]
+
+        for src_net, netns, link_netns, peer_netns, exp in cases:
+            tgt_net = netns or src_net
+            for typ in types:
+                cmd = "link add"
+                if netns:
+                    cmd += f" netns {netns}"
+                if link_netns:
+                    cmd += f" link-netns {link_netns}"
+                cmd += f" foo type {typ}"
+                if peer_netns:
+                    cmd += f" peer netns {peer_netns}"
+                ip(cmd, ns=src_net)
+                ksft_true(validate_link_netns(tgt_net, "foo", exp),
+                          f"{typ} peer_netns validation failed")
+                ip(f"link del foo", ns=tgt_net)
+
+
+def main() -> None:
+    ksft_run([test_event, test_link_net, test_peer_net])
+    ksft_exit()
+
+
+if __name__ == "__main__":
+    main()
diff --git a/tools/testing/selftests/net/netns-name.sh b/tools/testing/selftests/net/netns-name.sh
index 6974474c26f3..0be1905d1f2f 100755
--- a/tools/testing/selftests/net/netns-name.sh
+++ b/tools/testing/selftests/net/netns-name.sh
@@ -78,6 +78,16 @@ ip -netns $NS link show dev $ALT_NAME 2> /dev/null &&
     fail "Can still find alt-name after move"
 ip -netns $test_ns link del $DEV || fail
 
+#
+# Test no conflict of the same name/ifindex in different netns
+#
+ip -netns $NS link add name $DEV index 100 type dummy || fail
+ip -netns $NS link add netns $test_ns name $DEV index 100 type dummy ||
+    fail "Can create in netns without moving"
+ip -netns $test_ns link show dev $DEV >> /dev/null || fail "Device not found"
+ip -netns $NS link del $DEV || fail
+ip -netns $test_ns link del $DEV || fail
+
 echo -ne "$(basename $0) \t\t\t\t"
 if [ $RET_CODE -eq 0 ]; then
     echo "[  OK  ]"
-- 
2.48.1

Re: [PATCH net-next v10 00/13] net: Improve netns handling in rtnetlink

[Jakub Kicinski]

On Wed, 19 Feb 2025 20:50:26 +0800 Xiao Liang wrote:
> Patch 01 avoids link name conflict in different netns.
> 
> To achieve 2), there're mainly 3 steps:
> 
>  - Patch 02 packs newlink() parameters into a struct, including
>    the original "src_net" along with more netns context. No semantic
>    changes are introduced.
>  - Patch 03 ~ 09 converts device drivers to use the explicit netns
>    extracted from params.
>  - Patch 10 ~ 11 removes the old netns parameter, and converts
>    rtnetlink to create device in target netns directly.
> 
> Patch 12 ~ 13 adds some tests for link name and link netns.

Nice work, thank you!

Re: [PATCH net-next v10 00/13] net: Improve netns handling in rtnetlink

[patchwork-bot+netdevbpf]

Hello:

This series was applied to netdev/net-next.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Wed, 19 Feb 2025 20:50:26 +0800 you wrote:
> This patch series includes some netns-related improvements and fixes for
> rtnetlink, to make link creation more intuitive:
> 
>  1) Creating link in another net namespace doesn't conflict with link
>     names in current one.
>  2) Refector rtnetlink link creation. Create link in target namespace
>     directly.
> 
> [...]

Here is the summary with links:
  - [net-next,v10,01/13] rtnetlink: Lookup device in target netns when creating link
    https://git.kernel.org/netdev/net-next/c/ec061546c6cf
  - [net-next,v10,02/13] rtnetlink: Pack newlink() params into struct
    https://git.kernel.org/netdev/net-next/c/69c7be1b903f
  - [net-next,v10,03/13] net: Use link/peer netns in newlink() of rtnl_link_ops
    https://git.kernel.org/netdev/net-next/c/cf517ac16ad9
  - [net-next,v10,04/13] ieee802154: 6lowpan: Validate link netns in newlink() of rtnl_link_ops
    https://git.kernel.org/netdev/net-next/c/3533717581dd
  - [net-next,v10,05/13] net: ip_tunnel: Don't set tunnel->net in ip_tunnel_init()
    https://git.kernel.org/netdev/net-next/c/9e17b2a1a097
  - [net-next,v10,06/13] net: ip_tunnel: Use link netns in newlink() of rtnl_link_ops
    https://git.kernel.org/netdev/net-next/c/eacb1160536e
  - [net-next,v10,07/13] net: ipv6: Init tunnel link-netns before registering dev
    https://git.kernel.org/netdev/net-next/c/db014522f356
  - [net-next,v10,08/13] net: ipv6: Use link netns in newlink() of rtnl_link_ops
    https://git.kernel.org/netdev/net-next/c/5e72ce3e3980
  - [net-next,v10,09/13] net: xfrm: Use link netns in newlink() of rtnl_link_ops
    https://git.kernel.org/netdev/net-next/c/5314e3d68455
  - [net-next,v10,10/13] rtnetlink: Remove "net" from newlink params
    https://git.kernel.org/netdev/net-next/c/9c0fc091dc01
  - [net-next,v10,11/13] rtnetlink: Create link directly in target net namespace
    https://git.kernel.org/netdev/net-next/c/7ca486d08a30
  - [net-next,v10,12/13] selftests: net: Add python context manager for netns entering
    https://git.kernel.org/netdev/net-next/c/030329416232
  - [net-next,v10,13/13] selftests: net: Add test cases for link and peer netns
    https://git.kernel.org/netdev/net-next/c/85cb3711acb8

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