1 files changed, 739 insertions, 205 deletions

diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index b3f627ac4ed8..1dab44e13d3b 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * INET		An implementation of the TCP/IP protocol suite for the LINUX
  *		operating system.  INET is implemented using the  BSD Socket
@@ -6,15 +7,10 @@
  *		IPv4 Forwarding Information Base: FIB frontend.
  *
  * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
- *
- *		This program is free software; you can redistribute it and/or
- *		modify it under the terms of the GNU General Public License
- *		as published by the Free Software Foundation; either version
- *		2 of the License, or (at your option) any later version.
  */
 
 #include <linux/module.h>
-#include <asm/uaccess.h>
+#include <linux/uaccess.h>
 #include <linux/bitops.h>
 #include <linux/capability.h>
 #include <linux/types.h>
@@ -36,6 +32,8 @@
 #include <linux/list.h>
 #include <linux/slab.h>
 
+#include <net/flow.h>
+#include <net/inet_dscp.h>
 #include <net/ip.h>
 #include <net/protocol.h>
 #include <net/route.h>
@@ -43,8 +41,12 @@
 #include <net/sock.h>
 #include <net/arp.h>
 #include <net/ip_fib.h>
+#include <net/nexthop.h>
 #include <net/rtnetlink.h>
 #include <net/xfrm.h>
+#include <net/l3mdev.h>
+#include <net/lwtunnel.h>
+#include <trace/events/fib.h>
 
 #ifndef CONFIG_IP_MULTIPLE_TABLES
 
@@ -52,12 +54,12 @@ static int __net_init fib4_rules_init(struct net *net)
 {
 	struct fib_table *local_table, *main_table;
 
-	local_table = fib_trie_table(RT_TABLE_LOCAL);
-	if (local_table == NULL)
+	main_table  = fib_trie_table(RT_TABLE_MAIN, NULL);
+	if (!main_table)
 		return -ENOMEM;
 
-	main_table  = fib_trie_table(RT_TABLE_MAIN);
-	if (main_table == NULL)
+	local_table = fib_trie_table(RT_TABLE_LOCAL, main_table);
+	if (!local_table)
 		goto fail;
 
 	hlist_add_head_rcu(&local_table->tb_hlist,
@@ -67,14 +69,14 @@ static int __net_init fib4_rules_init(struct net *net)
 	return 0;
 
 fail:
-	kfree(local_table);
+	fib_free_table(main_table);
 	return -ENOMEM;
 }
 #else
 
 struct fib_table *fib_new_table(struct net *net, u32 id)
 {
-	struct fib_table *tb;
+	struct fib_table *tb, *alias = NULL;
 	unsigned int h;
 
 	if (id == 0)
@@ -83,23 +85,20 @@ struct fib_table *fib_new_table(struct net *net, u32 id)
 	if (tb)
 		return tb;
 
-	tb = fib_trie_table(id);
+	if (id == RT_TABLE_LOCAL && !net->ipv4.fib_has_custom_rules)
+		alias = fib_new_table(net, RT_TABLE_MAIN);
+
+	tb = fib_trie_table(id, alias);
 	if (!tb)
 		return NULL;
 
 	switch (id) {
-	case RT_TABLE_LOCAL:
-		net->ipv4.fib_local = tb;
-		break;
-
 	case RT_TABLE_MAIN:
-		net->ipv4.fib_main = tb;
+		rcu_assign_pointer(net->ipv4.fib_main, tb);
 		break;
-
 	case RT_TABLE_DEFAULT:
-		net->ipv4.fib_default = tb;
+		rcu_assign_pointer(net->ipv4.fib_default, tb);
 		break;
-
 	default:
 		break;
 	}
@@ -108,7 +107,9 @@ struct fib_table *fib_new_table(struct net *net, u32 id)
 	hlist_add_head_rcu(&tb->tb_hlist, &net->ipv4.fib_table_hash[h]);
 	return tb;
 }
+EXPORT_SYMBOL_GPL(fib_new_table);
 
+/* caller must hold either rtnl or rcu read lock */
 struct fib_table *fib_get_table(struct net *net, u32 id)
 {
 	struct fib_table *tb;
@@ -119,30 +120,80 @@ struct fib_table *fib_get_table(struct net *net, u32 id)
 		id = RT_TABLE_MAIN;
 	h = id & (FIB_TABLE_HASHSZ - 1);
 
-	rcu_read_lock();
 	head = &net->ipv4.fib_table_hash[h];
-	hlist_for_each_entry_rcu(tb, head, tb_hlist) {
-		if (tb->tb_id == id) {
-			rcu_read_unlock();
+	hlist_for_each_entry_rcu(tb, head, tb_hlist,
+				 lockdep_rtnl_is_held()) {
+		if (tb->tb_id == id)
 			return tb;
-		}
 	}
-	rcu_read_unlock();
 	return NULL;
 }
 #endif /* CONFIG_IP_MULTIPLE_TABLES */
 
-static void fib_flush(struct net *net)
+static void fib_replace_table(struct net *net, struct fib_table *old,
+			      struct fib_table *new)
+{
+#ifdef CONFIG_IP_MULTIPLE_TABLES
+	switch (new->tb_id) {
+	case RT_TABLE_MAIN:
+		rcu_assign_pointer(net->ipv4.fib_main, new);
+		break;
+	case RT_TABLE_DEFAULT:
+		rcu_assign_pointer(net->ipv4.fib_default, new);
+		break;
+	default:
+		break;
+	}
+
+#endif
+	/* replace the old table in the hlist */
+	hlist_replace_rcu(&old->tb_hlist, &new->tb_hlist);
+}
+
+int fib_unmerge(struct net *net)
+{
+	struct fib_table *old, *new, *main_table;
+
+	/* attempt to fetch local table if it has been allocated */
+	old = fib_get_table(net, RT_TABLE_LOCAL);
+	if (!old)
+		return 0;
+
+	new = fib_trie_unmerge(old);
+	if (!new)
+		return -ENOMEM;
+
+	/* table is already unmerged */
+	if (new == old)
+		return 0;
+
+	/* replace merged table with clean table */
+	fib_replace_table(net, old, new);
+	fib_free_table(old);
+
+	/* attempt to fetch main table if it has been allocated */
+	main_table = fib_get_table(net, RT_TABLE_MAIN);
+	if (!main_table)
+		return 0;
+
+	/* flush local entries from main table */
+	fib_table_flush_external(main_table);
+
+	return 0;
+}
+
+void fib_flush(struct net *net)
 {
 	int flushed = 0;
-	struct fib_table *tb;
-	struct hlist_head *head;
 	unsigned int h;
 
 	for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
-		head = &net->ipv4.fib_table_hash[h];
-		hlist_for_each_entry(tb, head, tb_hlist)
-			flushed += fib_table_flush(tb);
+		struct hlist_head *head = &net->ipv4.fib_table_hash[h];
+		struct hlist_node *tmp;
+		struct fib_table *tb;
+
+		hlist_for_each_entry_safe(tb, tmp, head, tb_hlist)
+			flushed += fib_table_flush(net, tb, false);
 	}
 
 	if (flushed)
@@ -155,51 +206,75 @@ static void fib_flush(struct net *net)
  */
 static inline unsigned int __inet_dev_addr_type(struct net *net,
 						const struct net_device *dev,
-						__be32 addr)
+						__be32 addr, u32 tb_id)
 {
 	struct flowi4		fl4 = { .daddr = addr };
 	struct fib_result	res;
 	unsigned int ret = RTN_BROADCAST;
-	struct fib_table *local_table;
+	struct fib_table *table;
 
 	if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr))
 		return RTN_BROADCAST;
 	if (ipv4_is_multicast(addr))
 		return RTN_MULTICAST;
 
-	local_table = fib_get_table(net, RT_TABLE_LOCAL);
-	if (local_table) {
+	rcu_read_lock();
+
+	table = fib_get_table(net, tb_id);
+	if (table) {
 		ret = RTN_UNICAST;
-		rcu_read_lock();
-		if (!fib_table_lookup(local_table, &fl4, &res, FIB_LOOKUP_NOREF)) {
-			if (!dev || dev == res.fi->fib_dev)
+		if (!fib_table_lookup(table, &fl4, &res, FIB_LOOKUP_NOREF)) {
+			struct fib_nh_common *nhc = fib_info_nhc(res.fi, 0);
+
+			if (!dev || dev == nhc->nhc_dev)
 				ret = res.type;
 		}
-		rcu_read_unlock();
 	}
+
+	rcu_read_unlock();
 	return ret;
 }
 
+unsigned int inet_addr_type_table(struct net *net, __be32 addr, u32 tb_id)
+{
+	return __inet_dev_addr_type(net, NULL, addr, tb_id);
+}
+EXPORT_SYMBOL(inet_addr_type_table);
+
 unsigned int inet_addr_type(struct net *net, __be32 addr)
 {
-	return __inet_dev_addr_type(net, NULL, addr);
+	return __inet_dev_addr_type(net, NULL, addr, RT_TABLE_LOCAL);
 }
 EXPORT_SYMBOL(inet_addr_type);
 
 unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev,
 				__be32 addr)
 {
-	return __inet_dev_addr_type(net, dev, addr);
+	u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL;
+
+	return __inet_dev_addr_type(net, dev, addr, rt_table);
 }
 EXPORT_SYMBOL(inet_dev_addr_type);
 
+/* inet_addr_type with dev == NULL but using the table from a dev
+ * if one is associated
+ */
+unsigned int inet_addr_type_dev_table(struct net *net,
+				      const struct net_device *dev,
+				      __be32 addr)
+{
+	u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL;
+
+	return __inet_dev_addr_type(net, NULL, addr, rt_table);
+}
+EXPORT_SYMBOL(inet_addr_type_dev_table);
+
 __be32 fib_compute_spec_dst(struct sk_buff *skb)
 {
 	struct net_device *dev = skb->dev;
 	struct in_device *in_dev;
 	struct fib_result res;
 	struct rtable *rt;
-	struct flowi4 fl4;
 	struct net *net;
 	int scope;
 
@@ -209,21 +284,22 @@ __be32 fib_compute_spec_dst(struct sk_buff *skb)
 		return ip_hdr(skb)->daddr;
 
 	in_dev = __in_dev_get_rcu(dev);
-	BUG_ON(!in_dev);
 
 	net = dev_net(dev);
 
 	scope = RT_SCOPE_UNIVERSE;
 	if (!ipv4_is_zeronet(ip_hdr(skb)->saddr)) {
-		fl4.flowi4_oif = 0;
-		fl4.flowi4_iif = LOOPBACK_IFINDEX;
-		fl4.daddr = ip_hdr(skb)->saddr;
-		fl4.saddr = 0;
-		fl4.flowi4_tos = RT_TOS(ip_hdr(skb)->tos);
-		fl4.flowi4_scope = scope;
-		fl4.flowi4_mark = IN_DEV_SRC_VMARK(in_dev) ? skb->mark : 0;
-		if (!fib_lookup(net, &fl4, &res))
-			return FIB_RES_PREFSRC(net, res);
+		bool vmark = in_dev && IN_DEV_SRC_VMARK(in_dev);
+		struct flowi4 fl4 = {
+			.flowi4_iif = LOOPBACK_IFINDEX,
+			.flowi4_l3mdev = l3mdev_master_ifindex_rcu(dev),
+			.daddr = ip_hdr(skb)->saddr,
+			.flowi4_dscp = ip4h_dscp(ip_hdr(skb)),
+			.flowi4_scope = scope,
+			.flowi4_mark = vmark ? skb->mark : 0,
+		};
+		if (!fib_lookup(net, &fl4, &res, 0))
+			return fib_result_prefsrc(net, &res);
 	} else {
 		scope = RT_SCOPE_LINK;
 	}
@@ -231,6 +307,33 @@ __be32 fib_compute_spec_dst(struct sk_buff *skb)
 	return inet_select_addr(dev, ip_hdr(skb)->saddr, scope);
 }
 
+bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev)
+{
+	bool dev_match = false;
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+	if (unlikely(fi->nh)) {
+		dev_match = nexthop_uses_dev(fi->nh, dev);
+	} else {
+		int ret;
+
+		for (ret = 0; ret < fib_info_num_path(fi); ret++) {
+			const struct fib_nh_common *nhc = fib_info_nhc(fi, ret);
+
+			if (nhc_l3mdev_matches_dev(nhc, dev)) {
+				dev_match = true;
+				break;
+			}
+		}
+	}
+#else
+	if (fib_info_nhc(fi, 0)->nhc_dev == dev)
+		dev_match = true;
+#endif
+
+	return dev_match;
+}
+EXPORT_SYMBOL_GPL(fib_info_nh_uses_dev);
+
 /* Given (packet source, input interface) and optional (dst, oif, tos):
  * - (main) check, that source is valid i.e. not broadcast or our local
  *   address.
@@ -240,52 +343,61 @@ __be32 fib_compute_spec_dst(struct sk_buff *skb)
  * called with rcu_read_lock()
  */
 static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
-				 u8 tos, int oif, struct net_device *dev,
+				 dscp_t dscp, int oif, struct net_device *dev,
 				 int rpf, struct in_device *idev, u32 *itag)
 {
-	int ret, no_addr, accept_local;
+	struct net *net = dev_net(dev);
+	enum skb_drop_reason reason;
+	struct flow_keys flkeys;
+	int ret, no_addr;
 	struct fib_result res;
 	struct flowi4 fl4;
-	struct net *net;
 	bool dev_match;
 
 	fl4.flowi4_oif = 0;
-	fl4.flowi4_iif = oif;
+	fl4.flowi4_l3mdev = l3mdev_master_ifindex_rcu(dev);
+	fl4.flowi4_iif = oif ? : LOOPBACK_IFINDEX;
 	fl4.daddr = src;
 	fl4.saddr = dst;
-	fl4.flowi4_tos = tos;
+	fl4.flowi4_dscp = dscp;
 	fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
+	fl4.flowi4_tun_key.tun_id = 0;
+	fl4.flowi4_flags = 0;
+	fl4.flowi4_uid = sock_net_uid(net, NULL);
+	fl4.flowi4_multipath_hash = 0;
 
 	no_addr = idev->ifa_list == NULL;
 
-	accept_local = IN_DEV_ACCEPT_LOCAL(idev);
 	fl4.flowi4_mark = IN_DEV_SRC_VMARK(idev) ? skb->mark : 0;
+	if (!fib4_rules_early_flow_dissect(net, skb, &fl4, &flkeys)) {
+		fl4.flowi4_proto = 0;
+		fl4.fl4_sport = 0;
+		fl4.fl4_dport = 0;
+	} else {
+		swap(fl4.fl4_sport, fl4.fl4_dport);
+	}
 
-	net = dev_net(dev);
-	if (fib_lookup(net, &fl4, &res))
+	if (fib_lookup(net, &fl4, &res, 0))
 		goto last_resort;
 	if (res.type != RTN_UNICAST) {
-		if (res.type != RTN_LOCAL || !accept_local)
+		if (res.type != RTN_LOCAL) {
+			reason = SKB_DROP_REASON_IP_INVALID_SOURCE;
 			goto e_inval;
+		} else if (!IN_DEV_ACCEPT_LOCAL(idev)) {
+			reason = SKB_DROP_REASON_IP_LOCAL_SOURCE;
+			goto e_inval;
+		}
 	}
 	fib_combine_itag(itag, &res);
-	dev_match = false;
 
-#ifdef CONFIG_IP_ROUTE_MULTIPATH
-	for (ret = 0; ret < res.fi->fib_nhs; ret++) {
-		struct fib_nh *nh = &res.fi->fib_nh[ret];
-
-		if (nh->nh_dev == dev) {
-			dev_match = true;
-			break;
-		}
-	}
-#else
-	if (FIB_RES_DEV(res) == dev)
-		dev_match = true;
-#endif
+	dev_match = fib_info_nh_uses_dev(res.fi, dev);
+	/* This is not common, loopback packets retain skb_dst so normally they
+	 * would not even hit this slow path.
+	 */
+	dev_match = dev_match || (res.type == RTN_LOCAL &&
+				  dev == net->loopback_dev);
 	if (dev_match) {
-		ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
+		ret = FIB_RES_NHC(res)->nhc_scope >= RT_SCOPE_HOST;
 		return ret;
 	}
 	if (no_addr)
@@ -295,9 +407,9 @@ static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
 	fl4.flowi4_oif = dev->ifindex;
 
 	ret = 0;
-	if (fib_lookup(net, &fl4, &res) == 0) {
+	if (fib_lookup(net, &fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE) == 0) {
 		if (res.type == RTN_UNICAST)
-			ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
+			ret = FIB_RES_NHC(res)->nhc_scope >= RT_SCOPE_HOST;
 	}
 	return ret;
 
@@ -308,24 +420,44 @@ last_resort:
 	return 0;
 
 e_inval:
-	return -EINVAL;
+	return -reason;
 e_rpf:
-	return -EXDEV;
+	return -SKB_DROP_REASON_IP_RPFILTER;
 }
 
 /* Ignore rp_filter for packets protected by IPsec. */
 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
-			u8 tos, int oif, struct net_device *dev,
+			dscp_t dscp, int oif, struct net_device *dev,
 			struct in_device *idev, u32 *itag)
 {
 	int r = secpath_exists(skb) ? 0 : IN_DEV_RPFILTER(idev);
+	struct net *net = dev_net(dev);
 
-	if (!r && !fib_num_tclassid_users(dev_net(dev)) &&
+	if (!r && !fib_num_tclassid_users(net) &&
 	    (dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev))) {
+		if (IN_DEV_ACCEPT_LOCAL(idev))
+			goto ok;
+		/* with custom local routes in place, checking local addresses
+		 * only will be too optimistic, with custom rules, checking
+		 * local addresses only can be too strict, e.g. due to vrf
+		 */
+		if (net->ipv4.fib_has_custom_local_routes ||
+		    fib4_has_custom_rules(net))
+			goto full_check;
+		/* Within the same container, it is regarded as a martian source,
+		 * and the same host but different containers are not.
+		 */
+		if (inet_lookup_ifaddr_rcu(net, src))
+			return -SKB_DROP_REASON_IP_LOCAL_SOURCE;
+
+ok:
 		*itag = 0;
 		return 0;
 	}
-	return __fib_validate_source(skb, src, dst, tos, oif, dev, r, idev, itag);
+
+full_check:
+	return __fib_validate_source(skb, src, dst, dscp, oif, dev, r, idev,
+				     itag);
 }
 
 static inline __be32 sk_extract_addr(struct sockaddr *addr)
@@ -417,16 +549,23 @@ static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt,
 		if (!dev)
 			return -ENODEV;
 		cfg->fc_oif = dev->ifindex;
+		cfg->fc_table = l3mdev_fib_table(dev);
 		if (colon) {
-			struct in_ifaddr *ifa;
-			struct in_device *in_dev = __in_dev_get_rtnl(dev);
+			const struct in_ifaddr *ifa;
+			struct in_device *in_dev;
+
+			in_dev = __in_dev_get_rtnl_net(dev);
 			if (!in_dev)
 				return -ENODEV;
+
 			*colon = ':';
-			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next)
+
+			in_dev_for_each_ifa_rtnl_net(net, ifa, in_dev) {
 				if (strcmp(ifa->ifa_label, devname) == 0)
 					break;
-			if (ifa == NULL)
+			}
+
+			if (!ifa)
 				return -ENODEV;
 			cfg->fc_prefsrc = ifa->ifa_local;
 		}
@@ -434,16 +573,23 @@ static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt,
 
 	addr = sk_extract_addr(&rt->rt_gateway);
 	if (rt->rt_gateway.sa_family == AF_INET && addr) {
-		cfg->fc_gw = addr;
+		unsigned int addr_type;
+
+		cfg->fc_gw4 = addr;
+		cfg->fc_gw_family = AF_INET;
+		addr_type = inet_addr_type_table(net, addr, cfg->fc_table);
 		if (rt->rt_flags & RTF_GATEWAY &&
-		    inet_addr_type(net, addr) == RTN_UNICAST)
+		    addr_type == RTN_UNICAST)
 			cfg->fc_scope = RT_SCOPE_UNIVERSE;
 	}
 
+	if (!cfg->fc_table)
+		cfg->fc_table = RT_TABLE_MAIN;
+
 	if (cmd == SIOCDELRT)
 		return 0;
 
-	if (rt->rt_flags & RTF_GATEWAY && !cfg->fc_gw)
+	if (rt->rt_flags & RTF_GATEWAY && !cfg->fc_gw_family)
 		return -EINVAL;
 
 	if (cfg->fc_scope == RT_SCOPE_NOWHERE)
@@ -453,8 +599,8 @@ static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt,
 		struct nlattr *mx;
 		int len = 0;
 
-		mx = kzalloc(3 * nla_total_size(4), GFP_KERNEL);
-		if (mx == NULL)
+		mx = kcalloc(3, nla_total_size(4), GFP_KERNEL);
+		if (!mx)
 			return -ENOMEM;
 
 		if (rt->rt_flags & RTF_MTU)
@@ -477,10 +623,9 @@ static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt,
  * Handle IP routing ioctl calls.
  * These are used to manipulate the routing tables
  */
-int ip_rt_ioctl(struct net *net, unsigned int cmd, void __user *arg)
+int ip_rt_ioctl(struct net *net, unsigned int cmd, struct rtentry *rt)
 {
 	struct fib_config cfg;
-	struct rtentry rt;
 	int err;
 
 	switch (cmd) {
@@ -489,24 +634,23 @@ int ip_rt_ioctl(struct net *net, unsigned int cmd, void __user *arg)
 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 			return -EPERM;
 
-		if (copy_from_user(&rt, arg, sizeof(rt)))
-			return -EFAULT;
-
-		rtnl_lock();
-		err = rtentry_to_fib_config(net, cmd, &rt, &cfg);
+		rtnl_net_lock(net);
+		err = rtentry_to_fib_config(net, cmd, rt, &cfg);
 		if (err == 0) {
 			struct fib_table *tb;
 
 			if (cmd == SIOCDELRT) {
 				tb = fib_get_table(net, cfg.fc_table);
 				if (tb)
-					err = fib_table_delete(tb, &cfg);
+					err = fib_table_delete(net, tb, &cfg,
+							       NULL);
 				else
 					err = -ESRCH;
 			} else {
 				tb = fib_new_table(net, cfg.fc_table);
 				if (tb)
-					err = fib_table_insert(tb, &cfg);
+					err = fib_table_insert(net, tb,
+							       &cfg, NULL);
 				else
 					err = -ENOBUFS;
 			}
@@ -514,13 +658,14 @@ int ip_rt_ioctl(struct net *net, unsigned int cmd, void __user *arg)
 			/* allocated by rtentry_to_fib_config() */
 			kfree(cfg.fc_mx);
 		}
-		rtnl_unlock();
+		rtnl_net_unlock(net);
 		return err;
 	}
 	return -EINVAL;
 }
 
 const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = {
+	[RTA_UNSPEC]		= { .strict_start_type = RTA_DPORT + 1 },
 	[RTA_DST]		= { .type = NLA_U32 },
 	[RTA_SRC]		= { .type = NLA_U32 },
 	[RTA_IIF]		= { .type = NLA_U32 },
@@ -531,24 +676,88 @@ const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = {
 	[RTA_METRICS]		= { .type = NLA_NESTED },
 	[RTA_MULTIPATH]		= { .len = sizeof(struct rtnexthop) },
 	[RTA_FLOW]		= { .type = NLA_U32 },
+	[RTA_ENCAP_TYPE]	= { .type = NLA_U16 },
+	[RTA_ENCAP]		= { .type = NLA_NESTED },
+	[RTA_UID]		= { .type = NLA_U32 },
+	[RTA_MARK]		= { .type = NLA_U32 },
+	[RTA_TABLE]		= { .type = NLA_U32 },
+	[RTA_IP_PROTO]		= { .type = NLA_U8 },
+	[RTA_SPORT]		= { .type = NLA_U16 },
+	[RTA_DPORT]		= { .type = NLA_U16 },
+	[RTA_NH_ID]		= { .type = NLA_U32 },
 };
 
+int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla,
+		    struct netlink_ext_ack *extack)
+{
+	struct rtvia *via;
+	int alen;
+
+	if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr)) {
+		NL_SET_ERR_MSG(extack, "Invalid attribute length for RTA_VIA");
+		return -EINVAL;
+	}
+
+	via = nla_data(nla);
+	alen = nla_len(nla) - offsetof(struct rtvia, rtvia_addr);
+
+	switch (via->rtvia_family) {
+	case AF_INET:
+		if (alen != sizeof(__be32)) {
+			NL_SET_ERR_MSG(extack, "Invalid IPv4 address in RTA_VIA");
+			return -EINVAL;
+		}
+		cfg->fc_gw_family = AF_INET;
+		cfg->fc_gw4 = *((__be32 *)via->rtvia_addr);
+		break;
+	case AF_INET6:
+#if IS_ENABLED(CONFIG_IPV6)
+		if (alen != sizeof(struct in6_addr)) {
+			NL_SET_ERR_MSG(extack, "Invalid IPv6 address in RTA_VIA");
+			return -EINVAL;
+		}
+		cfg->fc_gw_family = AF_INET6;
+		cfg->fc_gw6 = *((struct in6_addr *)via->rtvia_addr);
+#else
+		NL_SET_ERR_MSG(extack, "IPv6 support not enabled in kernel");
+		return -EINVAL;
+#endif
+		break;
+	default:
+		NL_SET_ERR_MSG(extack, "Unsupported address family in RTA_VIA");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
-			     struct nlmsghdr *nlh, struct fib_config *cfg)
+			     struct nlmsghdr *nlh, struct fib_config *cfg,
+			     struct netlink_ext_ack *extack)
 {
+	bool has_gw = false, has_via = false;
 	struct nlattr *attr;
 	int err, remaining;
 	struct rtmsg *rtm;
 
-	err = nlmsg_validate(nlh, sizeof(*rtm), RTA_MAX, rtm_ipv4_policy);
+	err = nlmsg_validate_deprecated(nlh, sizeof(*rtm), RTA_MAX,
+					rtm_ipv4_policy, extack);
 	if (err < 0)
 		goto errout;
 
 	memset(cfg, 0, sizeof(*cfg));
 
 	rtm = nlmsg_data(nlh);
+
+	if (!inet_validate_dscp(rtm->rtm_tos)) {
+		NL_SET_ERR_MSG(extack,
+			       "Invalid dsfield (tos): ECN bits must be 0");
+		err = -EINVAL;
+		goto errout;
+	}
+	cfg->fc_dscp = inet_dsfield_to_dscp(rtm->rtm_tos);
+
 	cfg->fc_dst_len = rtm->rtm_dst_len;
-	cfg->fc_tos = rtm->rtm_tos;
 	cfg->fc_table = rtm->rtm_table;
 	cfg->fc_protocol = rtm->rtm_protocol;
 	cfg->fc_scope = rtm->rtm_scope;
@@ -561,6 +770,7 @@ static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
 	cfg->fc_nlinfo.nl_net = net;
 
 	if (cfg->fc_type > RTN_MAX) {
+		NL_SET_ERR_MSG(extack, "Invalid route type");
 		err = -EINVAL;
 		goto errout;
 	}
@@ -574,7 +784,16 @@ static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
 			cfg->fc_oif = nla_get_u32(attr);
 			break;
 		case RTA_GATEWAY:
-			cfg->fc_gw = nla_get_be32(attr);
+			has_gw = true;
+			cfg->fc_gw4 = nla_get_be32(attr);
+			if (cfg->fc_gw4)
+				cfg->fc_gw_family = AF_INET;
+			break;
+		case RTA_VIA:
+			has_via = true;
+			err = fib_gw_from_via(cfg, attr, extack);
+			if (err)
+				goto errout;
 			break;
 		case RTA_PRIORITY:
 			cfg->fc_priority = nla_get_u32(attr);
@@ -587,6 +806,11 @@ static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
 			cfg->fc_mx_len = nla_len(attr);
 			break;
 		case RTA_MULTIPATH:
+			err = lwtunnel_valid_encap_type_attr(nla_data(attr),
+							     nla_len(attr),
+							     extack);
+			if (err < 0)
+				goto errout;
 			cfg->fc_mp = nla_data(attr);
 			cfg->fc_mp_len = nla_len(attr);
 			break;
@@ -596,84 +820,260 @@ static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
 		case RTA_TABLE:
 			cfg->fc_table = nla_get_u32(attr);
 			break;
+		case RTA_ENCAP:
+			cfg->fc_encap = attr;
+			break;
+		case RTA_ENCAP_TYPE:
+			cfg->fc_encap_type = nla_get_u16(attr);
+			err = lwtunnel_valid_encap_type(cfg->fc_encap_type,
+							extack);
+			if (err < 0)
+				goto errout;
+			break;
+		case RTA_NH_ID:
+			cfg->fc_nh_id = nla_get_u32(attr);
+			break;
 		}
 	}
 
+	if (cfg->fc_dst_len > 32) {
+		NL_SET_ERR_MSG(extack, "Invalid prefix length");
+		err = -EINVAL;
+		goto errout;
+	}
+
+	if (cfg->fc_dst_len < 32 && (ntohl(cfg->fc_dst) << cfg->fc_dst_len)) {
+		NL_SET_ERR_MSG(extack, "Invalid prefix for given prefix length");
+		err = -EINVAL;
+		goto errout;
+	}
+
+	if (cfg->fc_nh_id) {
+		if (cfg->fc_oif || cfg->fc_gw_family ||
+		    cfg->fc_encap || cfg->fc_mp) {
+			NL_SET_ERR_MSG(extack,
+				       "Nexthop specification and nexthop id are mutually exclusive");
+			err = -EINVAL;
+			goto errout;
+		}
+	}
+
+	if (has_gw && has_via) {
+		NL_SET_ERR_MSG(extack,
+			       "Nexthop configuration can not contain both GATEWAY and VIA");
+		err = -EINVAL;
+		goto errout;
+	}
+
+	if (!cfg->fc_table)
+		cfg->fc_table = RT_TABLE_MAIN;
+
 	return 0;
 errout:
 	return err;
 }
 
-static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh,
+			     struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct fib_config cfg;
 	struct fib_table *tb;
 	int err;
 
-	err = rtm_to_fib_config(net, skb, nlh, &cfg);
+	err = rtm_to_fib_config(net, skb, nlh, &cfg, extack);
 	if (err < 0)
 		goto errout;
 
+	rtnl_net_lock(net);
+
+	if (cfg.fc_nh_id && !nexthop_find_by_id(net, cfg.fc_nh_id)) {
+		NL_SET_ERR_MSG(extack, "Nexthop id does not exist");
+		err = -EINVAL;
+		goto unlock;
+	}
+
 	tb = fib_get_table(net, cfg.fc_table);
-	if (tb == NULL) {
+	if (!tb) {
+		NL_SET_ERR_MSG(extack, "FIB table does not exist");
 		err = -ESRCH;
-		goto errout;
+		goto unlock;
 	}
 
-	err = fib_table_delete(tb, &cfg);
+	err = fib_table_delete(net, tb, &cfg, extack);
+unlock:
+	rtnl_net_unlock(net);
 errout:
 	return err;
 }
 
-static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh,
+			     struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
 	struct fib_config cfg;
 	struct fib_table *tb;
 	int err;
 
-	err = rtm_to_fib_config(net, skb, nlh, &cfg);
+	err = rtm_to_fib_config(net, skb, nlh, &cfg, extack);
 	if (err < 0)
 		goto errout;
 
+	rtnl_net_lock(net);
+
 	tb = fib_new_table(net, cfg.fc_table);
-	if (tb == NULL) {
+	if (!tb) {
 		err = -ENOBUFS;
-		goto errout;
+		goto unlock;
 	}
 
-	err = fib_table_insert(tb, &cfg);
+	err = fib_table_insert(net, tb, &cfg, extack);
+	if (!err && cfg.fc_type == RTN_LOCAL)
+		net->ipv4.fib_has_custom_local_routes = true;
+
+unlock:
+	rtnl_net_unlock(net);
 errout:
 	return err;
 }
 
+int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
+			  struct fib_dump_filter *filter,
+			  struct netlink_callback *cb)
+{
+	struct netlink_ext_ack *extack = cb->extack;
+	struct nlattr *tb[RTA_MAX + 1];
+	struct rtmsg *rtm;
+	int err, i;
+
+	if (filter->rtnl_held)
+		ASSERT_RTNL();
+
+	rtm = nlmsg_payload(nlh, sizeof(*rtm));
+	if (!rtm) {
+		NL_SET_ERR_MSG(extack, "Invalid header for FIB dump request");
+		return -EINVAL;
+	}
+
+	if (rtm->rtm_dst_len || rtm->rtm_src_len  || rtm->rtm_tos   ||
+	    rtm->rtm_scope) {
+		NL_SET_ERR_MSG(extack, "Invalid values in header for FIB dump request");
+		return -EINVAL;
+	}
+
+	if (rtm->rtm_flags & ~(RTM_F_CLONED | RTM_F_PREFIX)) {
+		NL_SET_ERR_MSG(extack, "Invalid flags for FIB dump request");
+		return -EINVAL;
+	}
+	if (rtm->rtm_flags & RTM_F_CLONED)
+		filter->dump_routes = false;
+	else
+		filter->dump_exceptions = false;
+
+	filter->flags    = rtm->rtm_flags;
+	filter->protocol = rtm->rtm_protocol;
+	filter->rt_type  = rtm->rtm_type;
+	filter->table_id = rtm->rtm_table;
+
+	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX,
+					    rtm_ipv4_policy, extack);
+	if (err < 0)
+		return err;
+
+	for (i = 0; i <= RTA_MAX; ++i) {
+		int ifindex;
+
+		if (!tb[i])
+			continue;
+
+		switch (i) {
+		case RTA_TABLE:
+			filter->table_id = nla_get_u32(tb[i]);
+			break;
+		case RTA_OIF:
+			ifindex = nla_get_u32(tb[i]);
+			if (filter->rtnl_held)
+				filter->dev = __dev_get_by_index(net, ifindex);
+			else
+				filter->dev = dev_get_by_index_rcu(net, ifindex);
+			if (!filter->dev)
+				return -ENODEV;
+			break;
+		default:
+			NL_SET_ERR_MSG(extack, "Unsupported attribute in dump request");
+			return -EINVAL;
+		}
+	}
+
+	if (filter->flags || filter->protocol || filter->rt_type ||
+	    filter->table_id || filter->dev) {
+		filter->filter_set = 1;
+		cb->answer_flags = NLM_F_DUMP_FILTERED;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ip_valid_fib_dump_req);
+
 static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
 {
+	struct fib_dump_filter filter = {
+		.dump_routes = true,
+		.dump_exceptions = true,
+		.rtnl_held = false,
+	};
+	const struct nlmsghdr *nlh = cb->nlh;
 	struct net *net = sock_net(skb->sk);
 	unsigned int h, s_h;
 	unsigned int e = 0, s_e;
 	struct fib_table *tb;
 	struct hlist_head *head;
-	int dumped = 0;
+	int dumped = 0, err = 0;
 
-	if (nlmsg_len(cb->nlh) >= sizeof(struct rtmsg) &&
-	    ((struct rtmsg *) nlmsg_data(cb->nlh))->rtm_flags & RTM_F_CLONED)
-		return ip_rt_dump(skb, cb);
+	rcu_read_lock();
+	if (cb->strict_check) {
+		err = ip_valid_fib_dump_req(net, nlh, &filter, cb);
+		if (err < 0)
+			goto unlock;
+	} else if (nlmsg_len(nlh) >= sizeof(struct rtmsg)) {
+		struct rtmsg *rtm = nlmsg_data(nlh);
+
+		filter.flags = rtm->rtm_flags & (RTM_F_PREFIX | RTM_F_CLONED);
+	}
+
+	/* ipv4 does not use prefix flag */
+	if (filter.flags & RTM_F_PREFIX)
+		goto unlock;
+
+	if (filter.table_id) {
+		tb = fib_get_table(net, filter.table_id);
+		if (!tb) {
+			if (rtnl_msg_family(cb->nlh) != PF_INET)
+				goto unlock;
+
+			NL_SET_ERR_MSG(cb->extack, "ipv4: FIB table does not exist");
+			err = -ENOENT;
+			goto unlock;
+		}
+		err = fib_table_dump(tb, skb, cb, &filter);
+		goto unlock;
+	}
 
 	s_h = cb->args[0];
 	s_e = cb->args[1];
 
+	err = 0;
 	for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) {
 		e = 0;
 		head = &net->ipv4.fib_table_hash[h];
-		hlist_for_each_entry(tb, head, tb_hlist) {
+		hlist_for_each_entry_rcu(tb, head, tb_hlist) {
 			if (e < s_e)
 				goto next;
 			if (dumped)
 				memset(&cb->args[2], 0, sizeof(cb->args) -
 						 2 * sizeof(cb->args[0]));
-			if (fib_table_dump(tb, skb, cb) < 0)
+			err = fib_table_dump(tb, skb, cb, &filter);
+			if (err < 0)
 				goto out;
 			dumped = 1;
 next:
@@ -681,10 +1081,13 @@ next:
 		}
 	}
 out:
+
 	cb->args[1] = e;
 	cb->args[0] = h;
 
-	return skb->len;
+unlock:
+	rcu_read_unlock();
+	return err;
 }
 
 /* Prepare and feed intra-kernel routing request.
@@ -693,15 +1096,18 @@ out:
  * to fib engine. It is legal, because all events occur
  * only when netlink is already locked.
  */
-static void fib_magic(int cmd, int type, __be32 dst, int dst_len, struct in_ifaddr *ifa)
+static void fib_magic(int cmd, int type, __be32 dst, int dst_len,
+		      struct in_ifaddr *ifa, u32 rt_priority)
 {
 	struct net *net = dev_net(ifa->ifa_dev->dev);
+	u32 tb_id = l3mdev_fib_table(ifa->ifa_dev->dev);
 	struct fib_table *tb;
 	struct fib_config cfg = {
 		.fc_protocol = RTPROT_KERNEL,
 		.fc_type = type,
 		.fc_dst = dst,
 		.fc_dst_len = dst_len,
+		.fc_priority = rt_priority,
 		.fc_prefsrc = ifa->ifa_local,
 		.fc_oif = ifa->ifa_dev->dev->ifindex,
 		.fc_nlflags = NLM_F_CREATE | NLM_F_APPEND,
@@ -710,12 +1116,11 @@ static void fib_magic(int cmd, int type, __be32 dst, int dst_len, struct in_ifad
 		},
 	};
 
-	if (type == RTN_UNICAST)
-		tb = fib_new_table(net, RT_TABLE_MAIN);
-	else
-		tb = fib_new_table(net, RT_TABLE_LOCAL);
+	if (!tb_id)
+		tb_id = (type == RTN_UNICAST) ? RT_TABLE_MAIN : RT_TABLE_LOCAL;
 
-	if (tb == NULL)
+	tb = fib_new_table(net, tb_id);
+	if (!tb)
 		return;
 
 	cfg.fc_table = tb->tb_id;
@@ -726,9 +1131,9 @@ static void fib_magic(int cmd, int type, __be32 dst, int dst_len, struct in_ifad
 		cfg.fc_scope = RT_SCOPE_HOST;
 
 	if (cmd == RTM_NEWROUTE)
-		fib_table_insert(tb, &cfg);
+		fib_table_insert(net, tb, &cfg, NULL);
 	else
-		fib_table_delete(tb, &cfg);
+		fib_table_delete(net, tb, &cfg, NULL);
 }
 
 void fib_add_ifaddr(struct in_ifaddr *ifa)
@@ -742,36 +1147,64 @@ void fib_add_ifaddr(struct in_ifaddr *ifa)
 
 	if (ifa->ifa_flags & IFA_F_SECONDARY) {
 		prim = inet_ifa_byprefix(in_dev, prefix, mask);
-		if (prim == NULL) {
+		if (!prim) {
 			pr_warn("%s: bug: prim == NULL\n", __func__);
 			return;
 		}
 	}
 
-	fib_magic(RTM_NEWROUTE, RTN_LOCAL, addr, 32, prim);
+	fib_magic(RTM_NEWROUTE, RTN_LOCAL, addr, 32, prim, 0);
 
 	if (!(dev->flags & IFF_UP))
 		return;
 
 	/* Add broadcast address, if it is explicitly assigned. */
-	if (ifa->ifa_broadcast && ifa->ifa_broadcast != htonl(0xFFFFFFFF))
-		fib_magic(RTM_NEWROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim);
+	if (ifa->ifa_broadcast && ifa->ifa_broadcast != htonl(0xFFFFFFFF)) {
+		fib_magic(RTM_NEWROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32,
+			  prim, 0);
+		arp_invalidate(dev, ifa->ifa_broadcast, false);
+	}
 
 	if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags & IFA_F_SECONDARY) &&
 	    (prefix != addr || ifa->ifa_prefixlen < 32)) {
-		fib_magic(RTM_NEWROUTE,
-			  dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
-			  prefix, ifa->ifa_prefixlen, prim);
+		if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE))
+			fib_magic(RTM_NEWROUTE,
+				  dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
+				  prefix, ifa->ifa_prefixlen, prim,
+				  ifa->ifa_rt_priority);
 
-		/* Add network specific broadcasts, when it takes a sense */
+		/* Add the network broadcast address, when it makes sense */
 		if (ifa->ifa_prefixlen < 31) {
-			fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix, 32, prim);
 			fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix | ~mask,
-				  32, prim);
+				  32, prim, 0);
+			arp_invalidate(dev, prefix | ~mask, false);
 		}
 	}
 }
 
+void fib_modify_prefix_metric(struct in_ifaddr *ifa, u32 new_metric)
+{
+	__be32 prefix = ifa->ifa_address & ifa->ifa_mask;
+	struct in_device *in_dev = ifa->ifa_dev;
+	struct net_device *dev = in_dev->dev;
+
+	if (!(dev->flags & IFF_UP) ||
+	    ifa->ifa_flags & (IFA_F_SECONDARY | IFA_F_NOPREFIXROUTE) ||
+	    ipv4_is_zeronet(prefix) ||
+	    (prefix == ifa->ifa_local && ifa->ifa_prefixlen == 32))
+		return;
+
+	/* add the new */
+	fib_magic(RTM_NEWROUTE,
+		  dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
+		  prefix, ifa->ifa_prefixlen, ifa, new_metric);
+
+	/* delete the old */
+	fib_magic(RTM_DELROUTE,
+		  dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
+		  prefix, ifa->ifa_prefixlen, ifa, ifa->ifa_rt_priority);
+}
+
 /* Delete primary or secondary address.
  * Optionally, on secondary address promotion consider the addresses
  * from subnet iprim as deleted, even if they are in device list.
@@ -796,8 +1229,12 @@ void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim)
 
 	if (ifa->ifa_flags & IFA_F_SECONDARY) {
 		prim = inet_ifa_byprefix(in_dev, any, ifa->ifa_mask);
-		if (prim == NULL) {
-			pr_warn("%s: bug: prim == NULL\n", __func__);
+		if (!prim) {
+			/* if the device has been deleted, we don't perform
+			 * address promotion
+			 */
+			if (!in_dev->dead)
+				pr_warn("%s: bug: prim == NULL\n", __func__);
 			return;
 		}
 		if (iprim && iprim != prim) {
@@ -806,19 +1243,23 @@ void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim)
 		}
 	} else if (!ipv4_is_zeronet(any) &&
 		   (any != ifa->ifa_local || ifa->ifa_prefixlen < 32)) {
-		fib_magic(RTM_DELROUTE,
-			  dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
-			  any, ifa->ifa_prefixlen, prim);
+		if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE))
+			fib_magic(RTM_DELROUTE,
+				  dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
+				  any, ifa->ifa_prefixlen, prim, 0);
 		subnet = 1;
 	}
 
+	if (in_dev->dead)
+		goto no_promotions;
+
 	/* Deletion is more complicated than add.
 	 * We should take care of not to delete too much :-)
 	 *
 	 * Scan address list to be sure that addresses are really gone.
 	 */
-
-	for (ifa1 = in_dev->ifa_list; ifa1; ifa1 = ifa1->ifa_next) {
+	rcu_read_lock();
+	in_dev_for_each_ifa_rcu(ifa1, in_dev) {
 		if (ifa1 == ifa) {
 			/* promotion, keep the IP */
 			gone = 0;
@@ -886,28 +1327,36 @@ void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim)
 			}
 		}
 	}
+	rcu_read_unlock();
 
+no_promotions:
 	if (!(ok & BRD_OK))
-		fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim);
+		fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32,
+			  prim, 0);
 	if (subnet && ifa->ifa_prefixlen < 31) {
 		if (!(ok & BRD1_OK))
-			fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32, prim);
+			fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32,
+				  prim, 0);
 		if (!(ok & BRD0_OK))
-			fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32, prim);
+			fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32,
+				  prim, 0);
 	}
 	if (!(ok & LOCAL_OK)) {
-		fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim);
+		unsigned int addr_type;
+
+		fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim, 0);
 
 		/* Check, that this local address finally disappeared. */
-		if (gone &&
-		    inet_addr_type(dev_net(dev), ifa->ifa_local) != RTN_LOCAL) {
+		addr_type = inet_addr_type_dev_table(dev_net(dev), dev,
+						     ifa->ifa_local);
+		if (gone && addr_type != RTN_LOCAL) {
 			/* And the last, but not the least thing.
 			 * We must flush stray FIB entries.
 			 *
 			 * First of all, we scan fib_info list searching
 			 * for stray nexthop entries, then ignite fib_flush.
 			 */
-			if (fib_sync_down_addr(dev_net(dev), ifa->ifa_local))
+			if (fib_sync_down_addr(dev, ifa->ifa_local))
 				fib_flush(dev_net(dev));
 		}
 	}
@@ -917,23 +1366,27 @@ void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim)
 #undef BRD1_OK
 }
 
-static void nl_fib_lookup(struct fib_result_nl *frn, struct fib_table *tb)
+static void nl_fib_lookup(struct net *net, struct fib_result_nl *frn)
 {
 
 	struct fib_result       res;
 	struct flowi4           fl4 = {
 		.flowi4_mark = frn->fl_mark,
 		.daddr = frn->fl_addr,
-		.flowi4_tos = frn->fl_tos,
+		.flowi4_dscp = inet_dsfield_to_dscp(frn->fl_tos),
 		.flowi4_scope = frn->fl_scope,
 	};
+	struct fib_table *tb;
+
+	rcu_read_lock();
+
+	tb = fib_get_table(net, frn->tb_id_in);
 
 	frn->err = -ENOENT;
 	if (tb) {
 		local_bh_disable();
 
 		frn->tb_id = tb->tb_id;
-		rcu_read_lock();
 		frn->err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF);
 
 		if (!frn->err) {
@@ -942,9 +1395,10 @@ static void nl_fib_lookup(struct fib_result_nl *frn, struct fib_table *tb)
 			frn->type = res.type;
 			frn->scope = res.scope;
 		}
-		rcu_read_unlock();
 		local_bh_enable();
 	}
+
+	rcu_read_unlock();
 }
 
 static void nl_fib_input(struct sk_buff *skb)
@@ -952,29 +1406,27 @@ static void nl_fib_input(struct sk_buff *skb)
 	struct net *net;
 	struct fib_result_nl *frn;
 	struct nlmsghdr *nlh;
-	struct fib_table *tb;
 	u32 portid;
 
 	net = sock_net(skb->sk);
 	nlh = nlmsg_hdr(skb);
-	if (skb->len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len ||
+	if (skb->len < nlmsg_total_size(sizeof(*frn)) ||
+	    skb->len < nlh->nlmsg_len ||
 	    nlmsg_len(nlh) < sizeof(*frn))
 		return;
 
 	skb = netlink_skb_clone(skb, GFP_KERNEL);
-	if (skb == NULL)
+	if (!skb)
 		return;
 	nlh = nlmsg_hdr(skb);
 
-	frn = (struct fib_result_nl *) nlmsg_data(nlh);
-	tb = fib_get_table(net, frn->tb_id_in);
-
-	nl_fib_lookup(frn, tb);
+	frn = nlmsg_data(nlh);
+	nl_fib_lookup(net, frn);
 
 	portid = NETLINK_CB(skb).portid;      /* netlink portid */
 	NETLINK_CB(skb).portid = 0;        /* from kernel */
 	NETLINK_CB(skb).dst_group = 0;  /* unicast */
-	netlink_unicast(net->ipv4.fibnl, skb, portid, MSG_DONTWAIT);
+	nlmsg_unicast(net->ipv4.fibnl, skb, portid);
 }
 
 static int __net_init nl_fib_lookup_init(struct net *net)
@@ -985,7 +1437,7 @@ static int __net_init nl_fib_lookup_init(struct net *net)
 	};
 
 	sk = netlink_kernel_create(net, NETLINK_FIB_LOOKUP, &cfg);
-	if (sk == NULL)
+	if (!sk)
 		return -EAFNOSUPPORT;
 	net->ipv4.fibnl = sk;
 	return 0;
@@ -997,17 +1449,19 @@ static void nl_fib_lookup_exit(struct net *net)
 	net->ipv4.fibnl = NULL;
 }
 
-static void fib_disable_ip(struct net_device *dev, int force)
+static void fib_disable_ip(struct net_device *dev, unsigned long event,
+			   bool force)
 {
-	if (fib_sync_down_dev(dev, force))
+	if (fib_sync_down_dev(dev, event, force))
 		fib_flush(dev_net(dev));
-	rt_cache_flush(dev_net(dev));
+	else
+		rt_cache_flush(dev_net(dev));
 	arp_ifdown(dev);
 }
 
 static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
 {
-	struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
+	struct in_ifaddr *ifa = ptr;
 	struct net_device *dev = ifa->ifa_dev->dev;
 	struct net *net = dev_net(dev);
 
@@ -1015,21 +1469,21 @@ static int fib_inetaddr_event(struct notifier_block *this, unsigned long event,
 	case NETDEV_UP:
 		fib_add_ifaddr(ifa);
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
-		fib_sync_up(dev);
+		fib_sync_up(dev, RTNH_F_DEAD);
 #endif
 		atomic_inc(&net->ipv4.dev_addr_genid);
-		rt_cache_flush(dev_net(dev));
+		rt_cache_flush(net);
 		break;
 	case NETDEV_DOWN:
 		fib_del_ifaddr(ifa, NULL);
 		atomic_inc(&net->ipv4.dev_addr_genid);
-		if (ifa->ifa_dev->ifa_list == NULL) {
+		if (!ifa->ifa_dev->ifa_list) {
 			/* Last address was deleted from this interface.
 			 * Disable IP.
 			 */
-			fib_disable_ip(dev, 1);
+			fib_disable_ip(dev, event, true);
 		} else {
-			rt_cache_flush(dev_net(dev));
+			rt_cache_flush(net);
 		}
 		break;
 	}
@@ -1039,35 +1493,58 @@ static int fib_inetaddr_event(struct notifier_block *this, unsigned long event,
 static int fib_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
 {
 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+	struct netdev_notifier_changeupper_info *upper_info = ptr;
+	struct netdev_notifier_info_ext *info_ext = ptr;
 	struct in_device *in_dev;
 	struct net *net = dev_net(dev);
+	struct in_ifaddr *ifa;
+	unsigned int flags;
 
 	if (event == NETDEV_UNREGISTER) {
-		fib_disable_ip(dev, 2);
+		fib_disable_ip(dev, event, true);
 		rt_flush_dev(dev);
 		return NOTIFY_DONE;
 	}
 
 	in_dev = __in_dev_get_rtnl(dev);
+	if (!in_dev)
+		return NOTIFY_DONE;
 
 	switch (event) {
 	case NETDEV_UP:
-		for_ifa(in_dev) {
+		in_dev_for_each_ifa_rtnl(ifa, in_dev) {
 			fib_add_ifaddr(ifa);
-		} endfor_ifa(in_dev);
+		}
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
-		fib_sync_up(dev);
+		fib_sync_up(dev, RTNH_F_DEAD);
 #endif
 		atomic_inc(&net->ipv4.dev_addr_genid);
 		rt_cache_flush(net);
 		break;
 	case NETDEV_DOWN:
-		fib_disable_ip(dev, 0);
+		fib_disable_ip(dev, event, false);
 		break;
-	case NETDEV_CHANGEMTU:
 	case NETDEV_CHANGE:
+		flags = netif_get_flags(dev);
+		if (flags & (IFF_RUNNING | IFF_LOWER_UP))
+			fib_sync_up(dev, RTNH_F_LINKDOWN);
+		else
+			fib_sync_down_dev(dev, event, false);
 		rt_cache_flush(net);
 		break;
+	case NETDEV_CHANGEMTU:
+		fib_sync_mtu(dev, info_ext->ext.mtu);
+		rt_cache_flush(net);
+		break;
+	case NETDEV_CHANGEUPPER:
+		upper_info = ptr;
+		/* flush all routes if dev is linked to or unlinked from
+		 * an L3 master device (e.g., VRF)
+		 */
+		if (upper_info->upper_dev &&
+		    netif_is_l3_master(upper_info->upper_dev))
+			fib_disable_ip(dev, NETDEV_DOWN, true);
+		break;
 	}
 	return NOTIFY_DONE;
 }
@@ -1085,46 +1562,69 @@ static int __net_init ip_fib_net_init(struct net *net)
 	int err;
 	size_t size = sizeof(struct hlist_head) * FIB_TABLE_HASHSZ;
 
+	err = fib4_notifier_init(net);
+	if (err)
+		return err;
+
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+	/* Default to 3-tuple */
+	net->ipv4.sysctl_fib_multipath_hash_fields =
+		FIB_MULTIPATH_HASH_FIELD_DEFAULT_MASK;
+#endif
+
 	/* Avoid false sharing : Use at least a full cache line */
 	size = max_t(size_t, size, L1_CACHE_BYTES);
 
 	net->ipv4.fib_table_hash = kzalloc(size, GFP_KERNEL);
-	if (net->ipv4.fib_table_hash == NULL)
-		return -ENOMEM;
+	if (!net->ipv4.fib_table_hash) {
+		err = -ENOMEM;
+		goto err_table_hash_alloc;
+	}
 
 	err = fib4_rules_init(net);
 	if (err < 0)
-		goto fail;
+		goto err_rules_init;
 	return 0;
 
-fail:
+err_rules_init:
 	kfree(net->ipv4.fib_table_hash);
+err_table_hash_alloc:
+	fib4_notifier_exit(net);
 	return err;
 }
 
 static void ip_fib_net_exit(struct net *net)
 {
-	unsigned int i;
+	int i;
 
+	ASSERT_RTNL_NET(net);
 #ifdef CONFIG_IP_MULTIPLE_TABLES
-	fib4_rules_exit(net);
+	RCU_INIT_POINTER(net->ipv4.fib_main, NULL);
+	RCU_INIT_POINTER(net->ipv4.fib_default, NULL);
 #endif
-
-	rtnl_lock();
-	for (i = 0; i < FIB_TABLE_HASHSZ; i++) {
-		struct fib_table *tb;
-		struct hlist_head *head;
+	/* Destroy the tables in reverse order to guarantee that the
+	 * local table, ID 255, is destroyed before the main table, ID
+	 * 254. This is necessary as the local table may contain
+	 * references to data contained in the main table.
+	 */
+	for (i = FIB_TABLE_HASHSZ - 1; i >= 0; i--) {
+		struct hlist_head *head = &net->ipv4.fib_table_hash[i];
 		struct hlist_node *tmp;
+		struct fib_table *tb;
 
-		head = &net->ipv4.fib_table_hash[i];
 		hlist_for_each_entry_safe(tb, tmp, head, tb_hlist) {
 			hlist_del(&tb->tb_hlist);
-			fib_table_flush(tb);
+			fib_table_flush(net, tb, true);
 			fib_free_table(tb);
 		}
 	}
-	rtnl_unlock();
+
+#ifdef CONFIG_IP_MULTIPLE_TABLES
+	fib4_rules_exit(net);
+#endif
+
 	kfree(net->ipv4.fib_table_hash);
+	fib4_notifier_exit(net);
 }
 
 static int __net_init fib_net_init(struct net *net)
@@ -1132,14 +1632,20 @@ static int __net_init fib_net_init(struct net *net)
 	int error;
 
 #ifdef CONFIG_IP_ROUTE_CLASSID
-	net->ipv4.fib_num_tclassid_users = 0;
+	atomic_set(&net->ipv4.fib_num_tclassid_users, 0);
 #endif
 	error = ip_fib_net_init(net);
 	if (error < 0)
 		goto out;
+
+	error = fib4_semantics_init(net);
+	if (error)
+		goto out_semantics;
+
 	error = nl_fib_lookup_init(net);
 	if (error < 0)
 		goto out_nlfl;
+
 	error = fib_proc_init(net);
 	if (error < 0)
 		goto out_proc;
@@ -1149,7 +1655,11 @@ out:
 out_proc:
 	nl_fib_lookup_exit(net);
 out_nlfl:
+	fib4_semantics_exit(net);
+out_semantics:
+	rtnl_net_lock(net);
 	ip_fib_net_exit(net);
+	rtnl_net_unlock(net);
 	goto out;
 }
 
@@ -1157,23 +1667,47 @@ static void __net_exit fib_net_exit(struct net *net)
 {
 	fib_proc_exit(net);
 	nl_fib_lookup_exit(net);
-	ip_fib_net_exit(net);
+}
+
+static void __net_exit fib_net_exit_batch(struct list_head *net_list)
+{
+	struct net *net;
+
+	rtnl_lock();
+	list_for_each_entry(net, net_list, exit_list) {
+		__rtnl_net_lock(net);
+		ip_fib_net_exit(net);
+		__rtnl_net_unlock(net);
+	}
+	rtnl_unlock();
+
+	list_for_each_entry(net, net_list, exit_list)
+		fib4_semantics_exit(net);
 }
 
 static struct pernet_operations fib_net_ops = {
 	.init = fib_net_init,
 	.exit = fib_net_exit,
+	.exit_batch = fib_net_exit_batch,
+};
+
+static const struct rtnl_msg_handler fib_rtnl_msg_handlers[] __initconst = {
+	{.protocol = PF_INET, .msgtype = RTM_NEWROUTE,
+	 .doit = inet_rtm_newroute, .flags = RTNL_FLAG_DOIT_PERNET},
+	{.protocol = PF_INET, .msgtype = RTM_DELROUTE,
+	 .doit = inet_rtm_delroute, .flags = RTNL_FLAG_DOIT_PERNET},
+	{.protocol = PF_INET, .msgtype = RTM_GETROUTE, .dumpit = inet_dump_fib,
+	 .flags = RTNL_FLAG_DUMP_UNLOCKED | RTNL_FLAG_DUMP_SPLIT_NLM_DONE},
 };
 
 void __init ip_fib_init(void)
 {
-	rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL, NULL);
-	rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL, NULL);
-	rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib, NULL);
+	fib_trie_init();
 
 	register_pernet_subsys(&fib_net_ops);
+
 	register_netdevice_notifier(&fib_netdev_notifier);
 	register_inetaddr_notifier(&fib_inetaddr_notifier);
 
-	fib_trie_init();
+	rtnl_register_many(fib_rtnl_msg_handlers);
 }