Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 866 insertions, 0 deletions

diff --git a/drivers/net/bareudp.c b/drivers/net/bareudp.c
new file mode 100644
index 000000000..c3b5ed52d
--- /dev/null
+++ b/drivers/net/bareudp.c
@@ -0,0 +1,866 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Bareudp: UDP  tunnel encasulation for different Payload types like
+ * MPLS, NSH, IP, etc.
+ * Copyright (c) 2019 Nokia, Inc.
+ * Authors:  Martin Varghese, <martin.varghese@nokia.com>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/etherdevice.h>
+#include <linux/hash.h>
+#include <net/dst_metadata.h>
+#include <net/gro_cells.h>
+#include <net/rtnetlink.h>
+#include <net/protocol.h>
+#include <net/ip6_tunnel.h>
+#include <net/ip_tunnels.h>
+#include <net/udp_tunnel.h>
+#include <net/bareudp.h>
+
+#define BAREUDP_BASE_HLEN sizeof(struct udphdr)
+#define BAREUDP_IPV4_HLEN (sizeof(struct iphdr) + \
+			   sizeof(struct udphdr))
+#define BAREUDP_IPV6_HLEN (sizeof(struct ipv6hdr) + \
+			   sizeof(struct udphdr))
+
+static bool log_ecn_error = true;
+module_param(log_ecn_error, bool, 0644);
+MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
+
+/* per-network namespace private data for this module */
+
+static unsigned int bareudp_net_id;
+
+struct bareudp_net {
+	struct list_head        bareudp_list;
+	struct mutex		lock;
+};
+
+struct bareudp_conf {
+	__be16 ethertype;
+	__be16 port;
+	u16 sport_min;
+	bool multi_proto_mode;
+};
+
+/* Pseudo network device */
+struct bareudp_dev {
+	struct net         *net;        /* netns for packet i/o */
+	struct net_device  *dev;        /* netdev for bareudp tunnel */
+	__be16		   ethertype;
+	__be16             port;
+	u16	           sport_min;
+	bool               multi_proto_mode;
+	struct sock        __rcu *sk;
+	struct list_head   next;        /* bareudp node  on namespace list */
+	struct gro_cells   gro_cells;
+};
+
+static int bareudp_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
+{
+	struct metadata_dst *tun_dst = NULL;
+	IP_TUNNEL_DECLARE_FLAGS(key) = { };
+	struct bareudp_dev *bareudp;
+	unsigned short family;
+	unsigned int len;
+	__be16 proto;
+	void *oiph;
+	int err;
+	int nh;
+
+	bareudp = rcu_dereference_sk_user_data(sk);
+	if (!bareudp)
+		goto drop;
+
+	if (skb->protocol ==  htons(ETH_P_IP))
+		family = AF_INET;
+	else
+		family = AF_INET6;
+
+	if (bareudp->ethertype == htons(ETH_P_IP)) {
+		__u8 ipversion;
+
+		if (skb_copy_bits(skb, BAREUDP_BASE_HLEN, &ipversion,
+				  sizeof(ipversion))) {
+			dev_dstats_rx_dropped(bareudp->dev);
+			goto drop;
+		}
+		ipversion >>= 4;
+
+		if (ipversion == 4) {
+			proto = htons(ETH_P_IP);
+		} else if (ipversion == 6 && bareudp->multi_proto_mode) {
+			proto = htons(ETH_P_IPV6);
+		} else {
+			dev_dstats_rx_dropped(bareudp->dev);
+			goto drop;
+		}
+	} else if (bareudp->ethertype == htons(ETH_P_MPLS_UC)) {
+		struct iphdr *tunnel_hdr;
+
+		tunnel_hdr = (struct iphdr *)skb_network_header(skb);
+		if (tunnel_hdr->version == 4) {
+			if (!ipv4_is_multicast(tunnel_hdr->daddr)) {
+				proto = bareudp->ethertype;
+			} else if (bareudp->multi_proto_mode &&
+				   ipv4_is_multicast(tunnel_hdr->daddr)) {
+				proto = htons(ETH_P_MPLS_MC);
+			} else {
+				dev_dstats_rx_dropped(bareudp->dev);
+				goto drop;
+			}
+		} else {
+			int addr_type;
+			struct ipv6hdr *tunnel_hdr_v6;
+
+			tunnel_hdr_v6 = (struct ipv6hdr *)skb_network_header(skb);
+			addr_type =
+			ipv6_addr_type((struct in6_addr *)&tunnel_hdr_v6->daddr);
+			if (!(addr_type & IPV6_ADDR_MULTICAST)) {
+				proto = bareudp->ethertype;
+			} else if (bareudp->multi_proto_mode &&
+				   (addr_type & IPV6_ADDR_MULTICAST)) {
+				proto = htons(ETH_P_MPLS_MC);
+			} else {
+				dev_dstats_rx_dropped(bareudp->dev);
+				goto drop;
+			}
+		}
+	} else {
+		proto = bareudp->ethertype;
+	}
+
+	if (iptunnel_pull_header(skb, BAREUDP_BASE_HLEN,
+				 proto,
+				 !net_eq(bareudp->net,
+				 dev_net(bareudp->dev)))) {
+		dev_dstats_rx_dropped(bareudp->dev);
+		goto drop;
+	}
+
+	__set_bit(IP_TUNNEL_KEY_BIT, key);
+
+	tun_dst = udp_tun_rx_dst(skb, family, key, 0, 0);
+	if (!tun_dst) {
+		dev_dstats_rx_dropped(bareudp->dev);
+		goto drop;
+	}
+	skb_dst_set(skb, &tun_dst->dst);
+	skb->dev = bareudp->dev;
+	skb_reset_mac_header(skb);
+
+	/* Save offset of outer header relative to skb->head,
+	 * because we are going to reset the network header to the inner header
+	 * and might change skb->head.
+	 */
+	nh = skb_network_header(skb) - skb->head;
+
+	skb_reset_network_header(skb);
+
+	if (!pskb_inet_may_pull(skb)) {
+		DEV_STATS_INC(bareudp->dev, rx_length_errors);
+		DEV_STATS_INC(bareudp->dev, rx_errors);
+		goto drop;
+	}
+
+	/* Get the outer header. */
+	oiph = skb->head + nh;
+
+	if (!ipv6_mod_enabled() || family == AF_INET)
+		err = IP_ECN_decapsulate(oiph, skb);
+	else
+		err = IP6_ECN_decapsulate(oiph, skb);
+
+	if (unlikely(err)) {
+		if (log_ecn_error) {
+			if  (!ipv6_mod_enabled() || family == AF_INET)
+				net_info_ratelimited("non-ECT from %pI4 "
+						     "with TOS=%#x\n",
+						     &((struct iphdr *)oiph)->saddr,
+						     ((struct iphdr *)oiph)->tos);
+			else
+				net_info_ratelimited("non-ECT from %pI6\n",
+						     &((struct ipv6hdr *)oiph)->saddr);
+		}
+		if (err > 1) {
+			DEV_STATS_INC(bareudp->dev, rx_frame_errors);
+			DEV_STATS_INC(bareudp->dev, rx_errors);
+			goto drop;
+		}
+	}
+
+	len = skb->len;
+	err = gro_cells_receive(&bareudp->gro_cells, skb);
+	if (likely(err == NET_RX_SUCCESS))
+		dev_dstats_rx_add(bareudp->dev, len);
+
+	return 0;
+drop:
+	/* Consume bad packet */
+	kfree_skb(skb);
+
+	return 0;
+}
+
+static int bareudp_err_lookup(struct sock *sk, struct sk_buff *skb)
+{
+	return 0;
+}
+
+static int bareudp_init(struct net_device *dev)
+{
+	struct bareudp_dev *bareudp = netdev_priv(dev);
+	int err;
+
+	err = gro_cells_init(&bareudp->gro_cells, dev);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+static void bareudp_uninit(struct net_device *dev)
+{
+	struct bareudp_dev *bareudp = netdev_priv(dev);
+
+	gro_cells_destroy(&bareudp->gro_cells);
+}
+
+static struct sock *bareudp_create_sock(struct net *net, __be16 port)
+{
+	struct udp_port_cfg udp_conf;
+	struct socket *sock;
+	int err;
+
+	memset(&udp_conf, 0, sizeof(udp_conf));
+
+	if (ipv6_mod_enabled())
+		udp_conf.family = AF_INET6;
+	else
+		udp_conf.family = AF_INET;
+
+	udp_conf.local_udp_port = port;
+	/* Open UDP socket */
+	err = udp_sock_create(net, &udp_conf, &sock);
+	if (err < 0)
+		return ERR_PTR(err);
+
+	udp_allow_gso(sock->sk);
+	return sock->sk;
+}
+
+/* Create new listen socket if needed */
+static int bareudp_socket_create(struct bareudp_dev *bareudp, __be16 port)
+{
+	struct udp_tunnel_sock_cfg tunnel_cfg;
+	struct sock *sk;
+
+	sk = bareudp_create_sock(bareudp->net, port);
+	if (IS_ERR(sk))
+		return PTR_ERR(sk);
+
+	/* Mark socket as an encapsulation socket */
+	memset(&tunnel_cfg, 0, sizeof(tunnel_cfg));
+	tunnel_cfg.sk_user_data = bareudp;
+	tunnel_cfg.encap_type = 1;
+	tunnel_cfg.encap_rcv = bareudp_udp_encap_recv;
+	tunnel_cfg.encap_err_lookup = bareudp_err_lookup;
+	tunnel_cfg.encap_destroy = NULL;
+	setup_udp_tunnel_sock(bareudp->net, sk, &tunnel_cfg);
+
+	rcu_assign_pointer(bareudp->sk, sk);
+	return 0;
+}
+
+static int bareudp_open(struct net_device *dev)
+{
+	struct bareudp_dev *bareudp = netdev_priv(dev);
+
+	return bareudp_socket_create(bareudp, bareudp->port);
+}
+
+static void bareudp_sock_release(struct bareudp_dev *bareudp)
+{
+	struct sock *sk;
+
+	sk = rtnl_dereference(bareudp->sk);
+	rcu_assign_pointer(bareudp->sk, NULL);
+	udp_tunnel_sock_release(sk);
+}
+
+static int bareudp_stop(struct net_device *dev)
+{
+	struct bareudp_dev *bareudp = netdev_priv(dev);
+
+	bareudp_sock_release(bareudp);
+	return 0;
+}
+
+static int bareudp_xmit_skb(struct sk_buff *skb, struct net_device *dev,
+			    struct bareudp_dev *bareudp,
+			    const struct ip_tunnel_info *info)
+{
+	bool udp_sum = test_bit(IP_TUNNEL_CSUM_BIT, info->key.tun_flags);
+	bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
+	bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
+	struct sock *sk = rcu_dereference(bareudp->sk);
+	const struct ip_tunnel_key *key = &info->key;
+	struct rtable *rt;
+	__be16 sport, df;
+	int min_headroom;
+	__u8 tos, ttl;
+	__be32 saddr;
+	int err;
+
+	if (skb_vlan_inet_prepare(skb, skb->protocol != htons(ETH_P_TEB)))
+		return -EINVAL;
+
+	if (!sk)
+		return -ESHUTDOWN;
+
+	sport = udp_flow_src_port(bareudp->net, skb,
+				  bareudp->sport_min, USHRT_MAX,
+				  true);
+	rt = udp_tunnel_dst_lookup(skb, dev, bareudp->net, 0, &saddr, &info->key,
+				   sport, bareudp->port, key->tos,
+				   use_cache ?
+				   (struct dst_cache *)&info->dst_cache : NULL);
+
+	if (IS_ERR(rt))
+		return PTR_ERR(rt);
+
+	skb_tunnel_check_pmtu(skb, &rt->dst,
+			      BAREUDP_IPV4_HLEN + info->options_len, false);
+
+	tos = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
+	ttl = key->ttl;
+	df = test_bit(IP_TUNNEL_DONT_FRAGMENT_BIT, key->tun_flags) ?
+	     htons(IP_DF) : 0;
+	skb_scrub_packet(skb, xnet);
+
+	err = -ENOSPC;
+	if (!skb_pull(skb, skb_network_offset(skb)))
+		goto free_dst;
+
+	min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len +
+		BAREUDP_BASE_HLEN + info->options_len + sizeof(struct iphdr);
+
+	err = skb_cow_head(skb, min_headroom);
+	if (unlikely(err))
+		goto free_dst;
+
+	err = udp_tunnel_handle_offloads(skb, udp_sum);
+	if (err)
+		goto free_dst;
+
+	skb_set_inner_protocol(skb, bareudp->ethertype);
+	udp_tunnel_xmit_skb(rt, sk, skb, saddr, info->key.u.ipv4.dst,
+			    tos, ttl, df, sport, bareudp->port,
+			    !net_eq(bareudp->net, dev_net(bareudp->dev)),
+			    !test_bit(IP_TUNNEL_CSUM_BIT, info->key.tun_flags),
+			    0);
+	return 0;
+
+free_dst:
+	dst_release(&rt->dst);
+	return err;
+}
+
+static int bareudp6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
+			     struct bareudp_dev *bareudp,
+			     const struct ip_tunnel_info *info)
+{
+	bool udp_sum = test_bit(IP_TUNNEL_CSUM_BIT, info->key.tun_flags);
+	bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
+	bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
+	struct sock *sk = rcu_dereference(bareudp->sk);
+	const struct ip_tunnel_key *key = &info->key;
+	struct dst_entry *dst = NULL;
+	struct in6_addr saddr, daddr;
+	int min_headroom;
+	__u8 prio, ttl;
+	__be16 sport;
+	int err;
+
+	if (skb_vlan_inet_prepare(skb, skb->protocol != htons(ETH_P_TEB)))
+		return -EINVAL;
+
+	if (!sk)
+		return -ESHUTDOWN;
+
+	sport = udp_flow_src_port(bareudp->net, skb,
+				  bareudp->sport_min, USHRT_MAX,
+				  true);
+	dst = udp_tunnel6_dst_lookup(skb, dev, bareudp->net, sk, 0, &saddr,
+				     key, sport, bareudp->port, key->tos,
+				     use_cache ?
+				     (struct dst_cache *) &info->dst_cache : NULL);
+	if (IS_ERR(dst))
+		return PTR_ERR(dst);
+
+	skb_tunnel_check_pmtu(skb, dst, BAREUDP_IPV6_HLEN + info->options_len,
+			      false);
+
+	prio = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
+	ttl = key->ttl;
+
+	skb_scrub_packet(skb, xnet);
+
+	err = -ENOSPC;
+	if (!skb_pull(skb, skb_network_offset(skb)))
+		goto free_dst;
+
+	min_headroom = LL_RESERVED_SPACE(dst->dev) + dst->header_len +
+		BAREUDP_BASE_HLEN + info->options_len + sizeof(struct ipv6hdr);
+
+	err = skb_cow_head(skb, min_headroom);
+	if (unlikely(err))
+		goto free_dst;
+
+	err = udp_tunnel_handle_offloads(skb, udp_sum);
+	if (err)
+		goto free_dst;
+
+	daddr = info->key.u.ipv6.dst;
+	udp_tunnel6_xmit_skb(dst, sk, skb, dev,
+			     &saddr, &daddr, prio, ttl,
+			     info->key.label, sport, bareudp->port,
+			     !test_bit(IP_TUNNEL_CSUM_BIT,
+				       info->key.tun_flags),
+			     0);
+	return 0;
+
+free_dst:
+	dst_release(dst);
+	return err;
+}
+
+static bool bareudp_proto_valid(struct bareudp_dev *bareudp, __be16 proto)
+{
+	if (bareudp->ethertype == proto)
+		return true;
+
+	if (!bareudp->multi_proto_mode)
+		return false;
+
+	if (bareudp->ethertype == htons(ETH_P_MPLS_UC) &&
+	    proto == htons(ETH_P_MPLS_MC))
+		return true;
+
+	if (bareudp->ethertype == htons(ETH_P_IP) &&
+	    proto == htons(ETH_P_IPV6))
+		return true;
+
+	return false;
+}
+
+static netdev_tx_t bareudp_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct bareudp_dev *bareudp = netdev_priv(dev);
+	struct ip_tunnel_info *info = NULL;
+	int err;
+
+	if (!bareudp_proto_valid(bareudp, skb->protocol)) {
+		err = -EINVAL;
+		goto tx_error;
+	}
+
+	info = skb_tunnel_info(skb);
+	if (unlikely(!info || !(info->mode & IP_TUNNEL_INFO_TX))) {
+		err = -EINVAL;
+		goto tx_error;
+	}
+
+	rcu_read_lock();
+	if (ipv6_mod_enabled() && info->mode & IP_TUNNEL_INFO_IPV6)
+		err = bareudp6_xmit_skb(skb, dev, bareudp, info);
+	else
+		err = bareudp_xmit_skb(skb, dev, bareudp, info);
+
+	rcu_read_unlock();
+
+	if (likely(!err))
+		return NETDEV_TX_OK;
+tx_error:
+	dev_kfree_skb(skb);
+
+	if (err == -ELOOP)
+		DEV_STATS_INC(dev, collisions);
+	else if (err == -ENETUNREACH)
+		DEV_STATS_INC(dev, tx_carrier_errors);
+
+	DEV_STATS_INC(dev, tx_errors);
+	return NETDEV_TX_OK;
+}
+
+static int bareudp_fill_metadata_dst(struct net_device *dev,
+				     struct sk_buff *skb)
+{
+	struct ip_tunnel_info *info = skb_tunnel_info(skb);
+	struct bareudp_dev *bareudp = netdev_priv(dev);
+	bool use_cache;
+	__be16 sport;
+
+	use_cache = ip_tunnel_dst_cache_usable(skb, info);
+	sport = udp_flow_src_port(bareudp->net, skb,
+				  bareudp->sport_min, USHRT_MAX,
+				  true);
+
+	if (!ipv6_mod_enabled() || ip_tunnel_info_af(info) == AF_INET) {
+		struct rtable *rt;
+		__be32 saddr;
+
+		rt = udp_tunnel_dst_lookup(skb, dev, bareudp->net, 0, &saddr,
+					   &info->key, sport, bareudp->port,
+					   info->key.tos,
+					   use_cache ? &info->dst_cache : NULL);
+		if (IS_ERR(rt))
+			return PTR_ERR(rt);
+
+		ip_rt_put(rt);
+		info->key.u.ipv4.src = saddr;
+	} else if (ip_tunnel_info_af(info) == AF_INET6) {
+		struct dst_entry *dst;
+		struct in6_addr saddr;
+		struct sock *sk;
+
+		sk = rcu_dereference(bareudp->sk);
+		if (!sk)
+			return -ESHUTDOWN;
+
+		dst = udp_tunnel6_dst_lookup(skb, dev, bareudp->net, sk,
+					     0, &saddr, &info->key,
+					     sport, bareudp->port, info->key.tos,
+					     use_cache ? &info->dst_cache : NULL);
+		if (IS_ERR(dst))
+			return PTR_ERR(dst);
+
+		dst_release(dst);
+		info->key.u.ipv6.src = saddr;
+	} else {
+		return -EINVAL;
+	}
+
+	info->key.tp_src = sport;
+	info->key.tp_dst = bareudp->port;
+	return 0;
+}
+
+static const struct net_device_ops bareudp_netdev_ops = {
+	.ndo_init               = bareudp_init,
+	.ndo_uninit             = bareudp_uninit,
+	.ndo_open               = bareudp_open,
+	.ndo_stop               = bareudp_stop,
+	.ndo_start_xmit         = bareudp_xmit,
+	.ndo_fill_metadata_dst  = bareudp_fill_metadata_dst,
+};
+
+static const struct nla_policy bareudp_policy[IFLA_BAREUDP_MAX + 1] = {
+	[IFLA_BAREUDP_PORT]                = { .type = NLA_U16 },
+	[IFLA_BAREUDP_ETHERTYPE]	   = { .type = NLA_U16 },
+	[IFLA_BAREUDP_SRCPORT_MIN]         = { .type = NLA_U16 },
+	[IFLA_BAREUDP_MULTIPROTO_MODE]     = { .type = NLA_FLAG },
+};
+
+/* Info for udev, that this is a virtual tunnel endpoint */
+static const struct device_type bareudp_type = {
+	.name = "bareudp",
+};
+
+/* Initialize the device structure. */
+static void bareudp_setup(struct net_device *dev)
+{
+	dev->netdev_ops = &bareudp_netdev_ops;
+	dev->needs_free_netdev = true;
+	SET_NETDEV_DEVTYPE(dev, &bareudp_type);
+	dev->features    |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_FRAGLIST;
+	dev->features    |= NETIF_F_RXCSUM;
+	dev->features    |= NETIF_F_GSO_SOFTWARE;
+	dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_FRAGLIST;
+	dev->hw_features |= NETIF_F_RXCSUM;
+	dev->hw_features |= NETIF_F_GSO_SOFTWARE;
+	dev->hard_header_len = 0;
+	dev->addr_len = 0;
+	dev->mtu = ETH_DATA_LEN;
+	dev->min_mtu = IPV4_MIN_MTU;
+	dev->max_mtu = IP_MAX_MTU - BAREUDP_BASE_HLEN;
+	dev->type = ARPHRD_NONE;
+	netif_keep_dst(dev);
+	dev->priv_flags |= IFF_NO_QUEUE;
+	dev->lltx = true;
+	dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
+	dev->pcpu_stat_type = NETDEV_PCPU_STAT_DSTATS;
+}
+
+static int bareudp_validate(struct nlattr *tb[], struct nlattr *data[],
+			    struct netlink_ext_ack *extack)
+{
+	if (!data) {
+		NL_SET_ERR_MSG(extack,
+			       "Not enough attributes provided to perform the operation");
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int bareudp2info(struct nlattr *data[], struct bareudp_conf *conf,
+			struct netlink_ext_ack *extack)
+{
+	memset(conf, 0, sizeof(*conf));
+
+	if (!data[IFLA_BAREUDP_PORT]) {
+		NL_SET_ERR_MSG(extack, "port not specified");
+		return -EINVAL;
+	}
+	if (!data[IFLA_BAREUDP_ETHERTYPE]) {
+		NL_SET_ERR_MSG(extack, "ethertype not specified");
+		return -EINVAL;
+	}
+
+	conf->port = nla_get_u16(data[IFLA_BAREUDP_PORT]);
+	conf->ethertype = nla_get_u16(data[IFLA_BAREUDP_ETHERTYPE]);
+
+	if (data[IFLA_BAREUDP_SRCPORT_MIN])
+		conf->sport_min =  nla_get_u16(data[IFLA_BAREUDP_SRCPORT_MIN]);
+
+	if (data[IFLA_BAREUDP_MULTIPROTO_MODE])
+		conf->multi_proto_mode = true;
+
+	return 0;
+}
+
+static struct bareudp_dev *bareudp_find_dev(struct bareudp_net *bn,
+					    const struct bareudp_conf *conf)
+{
+	struct bareudp_dev *bareudp, *t = NULL;
+
+	mutex_lock(&bn->lock);
+
+	list_for_each_entry(bareudp, &bn->bareudp_list, next) {
+		if (conf->port == bareudp->port)
+			t = bareudp;
+	}
+
+	mutex_unlock(&bn->lock);
+
+	return t;
+}
+
+static int bareudp_configure(struct net *net, struct net_device *dev,
+			     struct bareudp_conf *conf,
+			     struct netlink_ext_ack *extack)
+{
+	struct bareudp_net *bn = net_generic(net, bareudp_net_id);
+	struct bareudp_dev *t, *bareudp = netdev_priv(dev);
+	int err;
+
+	bareudp->net = net;
+	bareudp->dev = dev;
+	t = bareudp_find_dev(bn, conf);
+	if (t) {
+		NL_SET_ERR_MSG(extack, "Another bareudp device using the same port already exists");
+		return -EBUSY;
+	}
+
+	if (conf->multi_proto_mode &&
+	    (conf->ethertype != htons(ETH_P_MPLS_UC) &&
+	     conf->ethertype != htons(ETH_P_IP))) {
+		NL_SET_ERR_MSG(extack, "Cannot set multiproto mode for this ethertype (only IPv4 and unicast MPLS are supported)");
+		return -EINVAL;
+	}
+
+	bareudp->port = conf->port;
+	bareudp->ethertype = conf->ethertype;
+	bareudp->sport_min = conf->sport_min;
+	bareudp->multi_proto_mode = conf->multi_proto_mode;
+
+	err = register_netdevice(dev);
+	if (err)
+		return err;
+
+	mutex_lock(&bn->lock);
+	list_add(&bareudp->next, &bn->bareudp_list);
+	mutex_unlock(&bn->lock);
+
+	return 0;
+}
+
+static int bareudp_link_config(struct net_device *dev,
+			       struct nlattr *tb[])
+{
+	int err;
+
+	if (tb[IFLA_MTU]) {
+		err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
+		if (err)
+			return err;
+	}
+	return 0;
+}
+
+static void __bareudp_dellink(struct net *net, struct net_device *dev,
+			      struct list_head *head)
+{
+	struct bareudp_dev *bareudp = netdev_priv(dev);
+
+	list_del_init(&bareudp->next);
+	unregister_netdevice_queue_net(net, dev, head);
+}
+
+static void bareudp_dellink(struct net_device *dev, struct list_head *head)
+{
+	struct bareudp_dev *bareudp = netdev_priv(dev);
+	struct bareudp_net *bn;
+
+	bn = net_generic(bareudp->net, bareudp_net_id);
+
+	mutex_lock(&bn->lock);
+	if (!list_empty(&bareudp->next))
+		__bareudp_dellink(dev_net(dev), dev, head);
+	mutex_unlock(&bn->lock);
+}
+
+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 bareudp_conf conf;
+	int err;
+
+	err = bareudp2info(data, &conf, extack);
+	if (err)
+		return err;
+
+	err = bareudp_configure(link_net, dev, &conf, extack);
+	if (err)
+		return err;
+
+	err = bareudp_link_config(dev, tb);
+	if (err)
+		goto err_unconfig;
+
+	return 0;
+
+err_unconfig:
+	bareudp_dellink(dev, NULL);
+	return err;
+}
+
+static size_t bareudp_get_size(const struct net_device *dev)
+{
+	return  nla_total_size(sizeof(__be16)) +  /* IFLA_BAREUDP_PORT */
+		nla_total_size(sizeof(__be16)) +  /* IFLA_BAREUDP_ETHERTYPE */
+		nla_total_size(sizeof(__u16))  +  /* IFLA_BAREUDP_SRCPORT_MIN */
+		nla_total_size(0)              +  /* IFLA_BAREUDP_MULTIPROTO_MODE */
+		0;
+}
+
+static int bareudp_fill_info(struct sk_buff *skb, const struct net_device *dev)
+{
+	struct bareudp_dev *bareudp = netdev_priv(dev);
+
+	if (nla_put_be16(skb, IFLA_BAREUDP_PORT, bareudp->port))
+		goto nla_put_failure;
+	if (nla_put_be16(skb, IFLA_BAREUDP_ETHERTYPE, bareudp->ethertype))
+		goto nla_put_failure;
+	if (nla_put_u16(skb, IFLA_BAREUDP_SRCPORT_MIN, bareudp->sport_min))
+		goto nla_put_failure;
+	if (bareudp->multi_proto_mode &&
+	    nla_put_flag(skb, IFLA_BAREUDP_MULTIPROTO_MODE))
+		goto nla_put_failure;
+
+	return 0;
+
+nla_put_failure:
+	return -EMSGSIZE;
+}
+
+static struct rtnl_link_ops bareudp_link_ops __read_mostly = {
+	.kind           = "bareudp",
+	.maxtype        = IFLA_BAREUDP_MAX,
+	.policy         = bareudp_policy,
+	.priv_size      = sizeof(struct bareudp_dev),
+	.setup          = bareudp_setup,
+	.validate       = bareudp_validate,
+	.newlink        = bareudp_newlink,
+	.dellink        = bareudp_dellink,
+	.get_size       = bareudp_get_size,
+	.fill_info      = bareudp_fill_info,
+};
+
+static __net_init int bareudp_init_net(struct net *net)
+{
+	struct bareudp_net *bn = net_generic(net, bareudp_net_id);
+
+	INIT_LIST_HEAD(&bn->bareudp_list);
+	mutex_init(&bn->lock);
+
+	return 0;
+}
+
+static void __net_exit bareudp_exit_rtnl_net(struct net *net,
+					     struct list_head *dev_kill_list)
+{
+	struct bareudp_net *bn = net_generic(net, bareudp_net_id);
+	struct bareudp_dev *bareudp, *next;
+
+	mutex_lock(&bn->lock);
+
+	list_for_each_entry_safe(bareudp, next, &bn->bareudp_list, next)
+		__bareudp_dellink(net, bareudp->dev, dev_kill_list);
+
+	mutex_unlock(&bn->lock);
+}
+
+static void __net_exit bareudp_exit_net(struct net *net)
+{
+	struct bareudp_net *bn = net_generic(net, bareudp_net_id);
+
+	WARN_ON_ONCE(!list_empty(&bn->bareudp_list));
+}
+
+static struct pernet_operations bareudp_net_ops = {
+	.init = bareudp_init_net,
+	.exit_rtnl = bareudp_exit_rtnl_net,
+	.exit = bareudp_exit_net,
+	.id   = &bareudp_net_id,
+	.size = sizeof(struct bareudp_net),
+};
+
+static int __init bareudp_init_module(void)
+{
+	int rc;
+
+	rc = register_pernet_subsys(&bareudp_net_ops);
+	if (rc)
+		goto out1;
+
+	rc = rtnl_link_register(&bareudp_link_ops);
+	if (rc)
+		goto out2;
+
+	return 0;
+out2:
+	unregister_pernet_subsys(&bareudp_net_ops);
+out1:
+	return rc;
+}
+late_initcall(bareudp_init_module);
+
+static void __exit bareudp_cleanup_module(void)
+{
+	rtnl_link_unregister(&bareudp_link_ops);
+	unregister_pernet_subsys(&bareudp_net_ops);
+}
+module_exit(bareudp_cleanup_module);
+
+MODULE_ALIAS_RTNL_LINK("bareudp");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Martin Varghese <martin.varghese@nokia.com>");
+MODULE_DESCRIPTION("Interface driver for UDP encapsulated traffic");