Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index ea4bd8a..a4b5bd4 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -1,11 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *	NET3	IP device support routines.
  *
- *		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.
- *
  *	Derived from the IP parts of dev.c 1.0.19
  * 		Authors:	Ross Biro
  *				Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
@@ -66,6 +62,11 @@
 #include <net/net_namespace.h>
 #include <net/addrconf.h>
 
+#define IPV6ONLY_FLAGS	\
+		(IFA_F_NODAD | IFA_F_OPTIMISTIC | IFA_F_DADFAILED | \
+		 IFA_F_HOMEADDRESS | IFA_F_TENTATIVE | \
+		 IFA_F_MANAGETEMPADDR | IFA_F_STABLE_PRIVACY)
+
 static struct ipv4_devconf ipv4_devconf = {
 	.data = {
 		[IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1,
@@ -100,6 +101,16 @@
 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
 	[IFA_FLAGS]		= { .type = NLA_U32 },
 	[IFA_RT_PRIORITY]	= { .type = NLA_U32 },
+	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
+};
+
+struct inet_fill_args {
+	u32 portid;
+	u32 seq;
+	int event;
+	unsigned int flags;
+	int netnsid;
+	int ifindex;
 };
 
 #define IN4_ADDR_HSIZE_SHIFT	8
@@ -184,7 +195,8 @@
 
 static BLOCKING_NOTIFIER_HEAD(inetaddr_chain);
 static BLOCKING_NOTIFIER_HEAD(inetaddr_validator_chain);
-static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
+static void inet_del_ifa(struct in_device *in_dev,
+			 struct in_ifaddr __rcu **ifap,
 			 int destroy);
 #ifdef CONFIG_SYSCTL
 static int devinet_sysctl_register(struct in_device *idev);
@@ -290,8 +302,8 @@
 
 static void inetdev_destroy(struct in_device *in_dev)
 {
-	struct in_ifaddr *ifa;
 	struct net_device *dev;
+	struct in_ifaddr *ifa;
 
 	ASSERT_RTNL();
 
@@ -301,7 +313,7 @@
 
 	ip_mc_destroy_dev(in_dev);
 
-	while ((ifa = in_dev->ifa_list) != NULL) {
+	while ((ifa = rtnl_dereference(in_dev->ifa_list)) != NULL) {
 		inet_del_ifa(in_dev, &in_dev->ifa_list, 0);
 		inet_free_ifa(ifa);
 	}
@@ -317,30 +329,35 @@
 
 int inet_addr_onlink(struct in_device *in_dev, __be32 a, __be32 b)
 {
+	const struct in_ifaddr *ifa;
+
 	rcu_read_lock();
-	for_primary_ifa(in_dev) {
+	in_dev_for_each_ifa_rcu(ifa, in_dev) {
 		if (inet_ifa_match(a, ifa)) {
 			if (!b || inet_ifa_match(b, ifa)) {
 				rcu_read_unlock();
 				return 1;
 			}
 		}
-	} endfor_ifa(in_dev);
+	}
 	rcu_read_unlock();
 	return 0;
 }
 
-static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
-			 int destroy, struct nlmsghdr *nlh, u32 portid)
+static void __inet_del_ifa(struct in_device *in_dev,
+			   struct in_ifaddr __rcu **ifap,
+			   int destroy, struct nlmsghdr *nlh, u32 portid)
 {
 	struct in_ifaddr *promote = NULL;
-	struct in_ifaddr *ifa, *ifa1 = *ifap;
-	struct in_ifaddr *last_prim = in_dev->ifa_list;
+	struct in_ifaddr *ifa, *ifa1;
+	struct in_ifaddr *last_prim;
 	struct in_ifaddr *prev_prom = NULL;
 	int do_promote = IN_DEV_PROMOTE_SECONDARIES(in_dev);
 
 	ASSERT_RTNL();
 
+	ifa1 = rtnl_dereference(*ifap);
+	last_prim = rtnl_dereference(in_dev->ifa_list);
 	if (in_dev->dead)
 		goto no_promotions;
 
@@ -349,9 +366,9 @@
 	 **/
 
 	if (!(ifa1->ifa_flags & IFA_F_SECONDARY)) {
-		struct in_ifaddr **ifap1 = &ifa1->ifa_next;
+		struct in_ifaddr __rcu **ifap1 = &ifa1->ifa_next;
 
-		while ((ifa = *ifap1) != NULL) {
+		while ((ifa = rtnl_dereference(*ifap1)) != NULL) {
 			if (!(ifa->ifa_flags & IFA_F_SECONDARY) &&
 			    ifa1->ifa_scope <= ifa->ifa_scope)
 				last_prim = ifa;
@@ -384,7 +401,7 @@
 	 * and later to add them back with new prefsrc. Do this
 	 * while all addresses are on the device list.
 	 */
-	for (ifa = promote; ifa; ifa = ifa->ifa_next) {
+	for (ifa = promote; ifa; ifa = rtnl_dereference(ifa->ifa_next)) {
 		if (ifa1->ifa_mask == ifa->ifa_mask &&
 		    inet_ifa_match(ifa1->ifa_address, ifa))
 			fib_del_ifaddr(ifa, ifa1);
@@ -410,19 +427,25 @@
 	blocking_notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1);
 
 	if (promote) {
-		struct in_ifaddr *next_sec = promote->ifa_next;
+		struct in_ifaddr *next_sec;
 
+		next_sec = rtnl_dereference(promote->ifa_next);
 		if (prev_prom) {
-			prev_prom->ifa_next = promote->ifa_next;
-			promote->ifa_next = last_prim->ifa_next;
-			last_prim->ifa_next = promote;
+			struct in_ifaddr *last_sec;
+
+			rcu_assign_pointer(prev_prom->ifa_next, next_sec);
+
+			last_sec = rtnl_dereference(last_prim->ifa_next);
+			rcu_assign_pointer(promote->ifa_next, last_sec);
+			rcu_assign_pointer(last_prim->ifa_next, promote);
 		}
 
 		promote->ifa_flags &= ~IFA_F_SECONDARY;
 		rtmsg_ifa(RTM_NEWADDR, promote, nlh, portid);
 		blocking_notifier_call_chain(&inetaddr_chain,
 				NETDEV_UP, promote);
-		for (ifa = next_sec; ifa; ifa = ifa->ifa_next) {
+		for (ifa = next_sec; ifa;
+		     ifa = rtnl_dereference(ifa->ifa_next)) {
 			if (ifa1->ifa_mask != ifa->ifa_mask ||
 			    !inet_ifa_match(ifa1->ifa_address, ifa))
 					continue;
@@ -434,7 +457,8 @@
 		inet_free_ifa(ifa1);
 }
 
-static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
+static void inet_del_ifa(struct in_device *in_dev,
+			 struct in_ifaddr __rcu **ifap,
 			 int destroy)
 {
 	__inet_del_ifa(in_dev, ifap, destroy, NULL, 0);
@@ -447,9 +471,10 @@
 static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh,
 			     u32 portid, struct netlink_ext_ack *extack)
 {
+	struct in_ifaddr __rcu **last_primary, **ifap;
 	struct in_device *in_dev = ifa->ifa_dev;
-	struct in_ifaddr *ifa1, **ifap, **last_primary;
 	struct in_validator_info ivi;
+	struct in_ifaddr *ifa1;
 	int ret;
 
 	ASSERT_RTNL();
@@ -462,8 +487,13 @@
 	ifa->ifa_flags &= ~IFA_F_SECONDARY;
 	last_primary = &in_dev->ifa_list;
 
-	for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL;
-	     ifap = &ifa1->ifa_next) {
+	/* Don't set IPv6 only flags to IPv4 addresses */
+	ifa->ifa_flags &= ~IPV6ONLY_FLAGS;
+
+	ifap = &in_dev->ifa_list;
+	ifa1 = rtnl_dereference(*ifap);
+
+	while (ifa1) {
 		if (!(ifa1->ifa_flags & IFA_F_SECONDARY) &&
 		    ifa->ifa_scope <= ifa1->ifa_scope)
 			last_primary = &ifa1->ifa_next;
@@ -479,6 +509,9 @@
 			}
 			ifa->ifa_flags |= IFA_F_SECONDARY;
 		}
+
+		ifap = &ifa1->ifa_next;
+		ifa1 = rtnl_dereference(*ifap);
 	}
 
 	/* Allow any devices that wish to register ifaddr validtors to weigh
@@ -504,8 +537,8 @@
 		ifap = last_primary;
 	}
 
-	ifa->ifa_next = *ifap;
-	*ifap = ifa;
+	rcu_assign_pointer(ifa->ifa_next, *ifap);
+	rcu_assign_pointer(*ifap, ifa);
 
 	inet_hash_insert(dev_net(in_dev->dev), ifa);
 
@@ -570,12 +603,14 @@
 struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix,
 				    __be32 mask)
 {
+	struct in_ifaddr *ifa;
+
 	ASSERT_RTNL();
 
-	for_primary_ifa(in_dev) {
+	in_dev_for_each_ifa_rtnl(ifa, in_dev) {
 		if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa))
 			return ifa;
-	} endfor_ifa(in_dev);
+	}
 	return NULL;
 }
 
@@ -603,16 +638,18 @@
 			    struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(skb->sk);
+	struct in_ifaddr __rcu **ifap;
 	struct nlattr *tb[IFA_MAX+1];
 	struct in_device *in_dev;
 	struct ifaddrmsg *ifm;
-	struct in_ifaddr *ifa, **ifap;
+	struct in_ifaddr *ifa;
+
 	int err = -EINVAL;
 
 	ASSERT_RTNL();
 
-	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy,
-			  extack);
+	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
+				     ifa_ipv4_policy, extack);
 	if (err < 0)
 		goto errout;
 
@@ -623,7 +660,7 @@
 		goto errout;
 	}
 
-	for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
+	for (ifap = &in_dev->ifa_list; (ifa = rtnl_dereference(*ifap)) != NULL;
 	     ifap = &ifa->ifa_next) {
 		if (tb[IFA_LOCAL] &&
 		    ifa->ifa_local != nla_get_in_addr(tb[IFA_LOCAL]))
@@ -711,15 +748,19 @@
 
 			if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME &&
 			    age >= ifa->ifa_valid_lft) {
-				struct in_ifaddr **ifap;
+				struct in_ifaddr __rcu **ifap;
+				struct in_ifaddr *tmp;
 
-				for (ifap = &ifa->ifa_dev->ifa_list;
-				     *ifap != NULL; ifap = &(*ifap)->ifa_next) {
-					if (*ifap == ifa) {
+				ifap = &ifa->ifa_dev->ifa_list;
+				tmp = rtnl_dereference(*ifap);
+				while (tmp) {
+					if (tmp == ifa) {
 						inet_del_ifa(ifa->ifa_dev,
 							     ifap, 1);
 						break;
 					}
+					ifap = &tmp->ifa_next;
+					tmp = rtnl_dereference(*ifap);
 				}
 			} else if (ifa->ifa_preferred_lft !=
 				   INFINITY_LIFE_TIME &&
@@ -773,7 +814,8 @@
 }
 
 static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh,
-				       __u32 *pvalid_lft, __u32 *pprefered_lft)
+				       __u32 *pvalid_lft, __u32 *pprefered_lft,
+				       struct netlink_ext_ack *extack)
 {
 	struct nlattr *tb[IFA_MAX+1];
 	struct in_ifaddr *ifa;
@@ -782,8 +824,8 @@
 	struct in_device *in_dev;
 	int err;
 
-	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy,
-			  NULL);
+	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
+				     ifa_ipv4_policy, extack);
 	if (err < 0)
 		goto errout;
 
@@ -862,13 +904,12 @@
 static struct in_ifaddr *find_matching_ifa(struct in_ifaddr *ifa)
 {
 	struct in_device *in_dev = ifa->ifa_dev;
-	struct in_ifaddr *ifa1, **ifap;
+	struct in_ifaddr *ifa1;
 
 	if (!ifa->ifa_local)
 		return NULL;
 
-	for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL;
-	     ifap = &ifa1->ifa_next) {
+	in_dev_for_each_ifa_rtnl(ifa1, in_dev) {
 		if (ifa1->ifa_mask == ifa->ifa_mask &&
 		    inet_ifa_match(ifa1->ifa_address, ifa) &&
 		    ifa1->ifa_local == ifa->ifa_local)
@@ -888,7 +929,7 @@
 
 	ASSERT_RTNL();
 
-	ifa = rtm_to_ifaddr(net, nlh, &valid_lft, &prefered_lft);
+	ifa = rtm_to_ifaddr(net, nlh, &valid_lft, &prefered_lft, extack);
 	if (IS_ERR(ifa))
 		return PTR_ERR(ifa);
 
@@ -941,17 +982,18 @@
 {
 	int rc = -1;	/* Something else, probably a multicast. */
 
-	if (ipv4_is_zeronet(addr))
+	if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr))
 		rc = 0;
 	else {
 		__u32 haddr = ntohl(addr);
-
 		if (IN_CLASSA(haddr))
 			rc = 8;
 		else if (IN_CLASSB(haddr))
 			rc = 16;
 		else if (IN_CLASSC(haddr))
 			rc = 24;
+		else if (IN_CLASSE(haddr))
+			rc = 32;
 	}
 
 	return rc;
@@ -962,8 +1004,8 @@
 {
 	struct sockaddr_in sin_orig;
 	struct sockaddr_in *sin = (struct sockaddr_in *)&ifr->ifr_addr;
+	struct in_ifaddr __rcu **ifap = NULL;
 	struct in_device *in_dev;
-	struct in_ifaddr **ifap = NULL;
 	struct in_ifaddr *ifa = NULL;
 	struct net_device *dev;
 	char *colon;
@@ -1034,7 +1076,9 @@
 			/* note: we only do this for a limited set of ioctls
 			   and only if the original address family was AF_INET.
 			   This is checked above. */
-			for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
+
+			for (ifap = &in_dev->ifa_list;
+			     (ifa = rtnl_dereference(*ifap)) != NULL;
 			     ifap = &ifa->ifa_next) {
 				if (!strcmp(ifr->ifr_name, ifa->ifa_label) &&
 				    sin_orig.sin_addr.s_addr ==
@@ -1047,7 +1091,8 @@
 		   4.3BSD-style and passed in junk so we fall back to
 		   comparing just the label */
 		if (!ifa) {
-			for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
+			for (ifap = &in_dev->ifa_list;
+			     (ifa = rtnl_dereference(*ifap)) != NULL;
 			     ifap = &ifa->ifa_next)
 				if (!strcmp(ifr->ifr_name, ifa->ifa_label))
 					break;
@@ -1089,7 +1134,7 @@
 				inet_del_ifa(in_dev, ifap, 1);
 			break;
 		}
-		ret = dev_change_flags(dev, ifr->ifr_flags);
+		ret = dev_change_flags(dev, ifr->ifr_flags, NULL);
 		break;
 
 	case SIOCSIFADDR:	/* Set interface address (and family) */
@@ -1196,7 +1241,7 @@
 static int inet_gifconf(struct net_device *dev, char __user *buf, int len, int size)
 {
 	struct in_device *in_dev = __in_dev_get_rtnl(dev);
-	struct in_ifaddr *ifa;
+	const struct in_ifaddr *ifa;
 	struct ifreq ifr;
 	int done = 0;
 
@@ -1206,7 +1251,7 @@
 	if (!in_dev)
 		goto out;
 
-	for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
+	in_dev_for_each_ifa_rtnl(ifa, in_dev) {
 		if (!buf) {
 			done += size;
 			continue;
@@ -1234,18 +1279,24 @@
 static __be32 in_dev_select_addr(const struct in_device *in_dev,
 				 int scope)
 {
-	for_primary_ifa(in_dev) {
+	const struct in_ifaddr *ifa;
+
+	in_dev_for_each_ifa_rcu(ifa, in_dev) {
+		if (ifa->ifa_flags & IFA_F_SECONDARY)
+			continue;
 		if (ifa->ifa_scope != RT_SCOPE_LINK &&
 		    ifa->ifa_scope <= scope)
 			return ifa->ifa_local;
-	} endfor_ifa(in_dev);
+	}
 
 	return 0;
 }
 
 __be32 inet_select_addr(const struct net_device *dev, __be32 dst, int scope)
 {
+	const struct in_ifaddr *ifa;
 	__be32 addr = 0;
+	unsigned char localnet_scope = RT_SCOPE_HOST;
 	struct in_device *in_dev;
 	struct net *net = dev_net(dev);
 	int master_idx;
@@ -1255,8 +1306,13 @@
 	if (!in_dev)
 		goto no_in_dev;
 
-	for_primary_ifa(in_dev) {
-		if (ifa->ifa_scope > scope)
+	if (unlikely(IN_DEV_ROUTE_LOCALNET(in_dev)))
+		localnet_scope = RT_SCOPE_LINK;
+
+	in_dev_for_each_ifa_rcu(ifa, in_dev) {
+		if (ifa->ifa_flags & IFA_F_SECONDARY)
+			continue;
+		if (min(ifa->ifa_scope, localnet_scope) > scope)
 			continue;
 		if (!dst || inet_ifa_match(dst, ifa)) {
 			addr = ifa->ifa_local;
@@ -1264,7 +1320,7 @@
 		}
 		if (!addr)
 			addr = ifa->ifa_local;
-	} endfor_ifa(in_dev);
+	}
 
 	if (addr)
 		goto out_unlock;
@@ -1309,13 +1365,20 @@
 static __be32 confirm_addr_indev(struct in_device *in_dev, __be32 dst,
 			      __be32 local, int scope)
 {
-	int same = 0;
+	unsigned char localnet_scope = RT_SCOPE_HOST;
+	const struct in_ifaddr *ifa;
 	__be32 addr = 0;
+	int same = 0;
 
-	for_ifa(in_dev) {
+	if (unlikely(IN_DEV_ROUTE_LOCALNET(in_dev)))
+		localnet_scope = RT_SCOPE_LINK;
+
+	in_dev_for_each_ifa_rcu(ifa, in_dev) {
+		unsigned char min_scope = min(ifa->ifa_scope, localnet_scope);
+
 		if (!addr &&
 		    (local == ifa->ifa_local || !local) &&
-		    ifa->ifa_scope <= scope) {
+		    min_scope <= scope) {
 			addr = ifa->ifa_local;
 			if (same)
 				break;
@@ -1330,7 +1393,7 @@
 				if (inet_ifa_match(addr, ifa))
 					break;
 				/* No, then can we use new local src? */
-				if (ifa->ifa_scope <= scope) {
+				if (min_scope <= scope) {
 					addr = ifa->ifa_local;
 					break;
 				}
@@ -1338,7 +1401,7 @@
 				same = 0;
 			}
 		}
-	} endfor_ifa(in_dev);
+	}
 
 	return same ? addr : 0;
 }
@@ -1412,7 +1475,7 @@
 	struct in_ifaddr *ifa;
 	int named = 0;
 
-	for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
+	in_dev_for_each_ifa_rtnl(ifa, in_dev) {
 		char old[IFNAMSIZ], *dot;
 
 		memcpy(old, ifa->ifa_label, IFNAMSIZ);
@@ -1442,10 +1505,9 @@
 					struct in_device *in_dev)
 
 {
-	struct in_ifaddr *ifa;
+	const struct in_ifaddr *ifa;
 
-	for (ifa = in_dev->ifa_list; ifa;
-	     ifa = ifa->ifa_next) {
+	in_dev_for_each_ifa_rtnl(ifa, in_dev) {
 		arp_send(ARPOP_REQUEST, ETH_P_ARP,
 			 ifa->ifa_local, dev,
 			 ifa->ifa_local, NULL,
@@ -1584,13 +1646,14 @@
 }
 
 static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa,
-			    u32 portid, u32 seq, int event, unsigned int flags)
+			    struct inet_fill_args *args)
 {
 	struct ifaddrmsg *ifm;
 	struct nlmsghdr  *nlh;
 	u32 preferred, valid;
 
-	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*ifm), flags);
+	nlh = nlmsg_put(skb, args->portid, args->seq, args->event, sizeof(*ifm),
+			args->flags);
 	if (!nlh)
 		return -EMSGSIZE;
 
@@ -1601,6 +1664,10 @@
 	ifm->ifa_scope = ifa->ifa_scope;
 	ifm->ifa_index = ifa->ifa_dev->dev->ifindex;
 
+	if (args->netnsid >= 0 &&
+	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
+		goto nla_put_failure;
+
 	if (!(ifm->ifa_flags & IFA_F_PERMANENT)) {
 		preferred = ifa->ifa_preferred_lft;
 		valid = ifa->ifa_valid_lft;
@@ -1645,27 +1712,144 @@
 	return -EMSGSIZE;
 }
 
+static int inet_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
+				      struct inet_fill_args *fillargs,
+				      struct net **tgt_net, struct sock *sk,
+				      struct netlink_callback *cb)
+{
+	struct netlink_ext_ack *extack = cb->extack;
+	struct nlattr *tb[IFA_MAX+1];
+	struct ifaddrmsg *ifm;
+	int err, i;
+
+	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
+		NL_SET_ERR_MSG(extack, "ipv4: Invalid header for address dump request");
+		return -EINVAL;
+	}
+
+	ifm = nlmsg_data(nlh);
+	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
+		NL_SET_ERR_MSG(extack, "ipv4: Invalid values in header for address dump request");
+		return -EINVAL;
+	}
+
+	fillargs->ifindex = ifm->ifa_index;
+	if (fillargs->ifindex) {
+		cb->answer_flags |= NLM_F_DUMP_FILTERED;
+		fillargs->flags |= NLM_F_DUMP_FILTERED;
+	}
+
+	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
+					    ifa_ipv4_policy, extack);
+	if (err < 0)
+		return err;
+
+	for (i = 0; i <= IFA_MAX; ++i) {
+		if (!tb[i])
+			continue;
+
+		if (i == IFA_TARGET_NETNSID) {
+			struct net *net;
+
+			fillargs->netnsid = nla_get_s32(tb[i]);
+
+			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
+			if (IS_ERR(net)) {
+				fillargs->netnsid = -1;
+				NL_SET_ERR_MSG(extack, "ipv4: Invalid target network namespace id");
+				return PTR_ERR(net);
+			}
+			*tgt_net = net;
+		} else {
+			NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in dump request");
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+static int in_dev_dump_addr(struct in_device *in_dev, struct sk_buff *skb,
+			    struct netlink_callback *cb, int s_ip_idx,
+			    struct inet_fill_args *fillargs)
+{
+	struct in_ifaddr *ifa;
+	int ip_idx = 0;
+	int err;
+
+	in_dev_for_each_ifa_rtnl(ifa, in_dev) {
+		if (ip_idx < s_ip_idx) {
+			ip_idx++;
+			continue;
+		}
+		err = inet_fill_ifaddr(skb, ifa, fillargs);
+		if (err < 0)
+			goto done;
+
+		nl_dump_check_consistent(cb, nlmsg_hdr(skb));
+		ip_idx++;
+	}
+	err = 0;
+
+done:
+	cb->args[2] = ip_idx;
+
+	return err;
+}
+
 static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
 {
+	const struct nlmsghdr *nlh = cb->nlh;
+	struct inet_fill_args fillargs = {
+		.portid = NETLINK_CB(cb->skb).portid,
+		.seq = nlh->nlmsg_seq,
+		.event = RTM_NEWADDR,
+		.flags = NLM_F_MULTI,
+		.netnsid = -1,
+	};
 	struct net *net = sock_net(skb->sk);
+	struct net *tgt_net = net;
 	int h, s_h;
 	int idx, s_idx;
-	int ip_idx, s_ip_idx;
+	int s_ip_idx;
 	struct net_device *dev;
 	struct in_device *in_dev;
-	struct in_ifaddr *ifa;
 	struct hlist_head *head;
+	int err = 0;
 
 	s_h = cb->args[0];
 	s_idx = idx = cb->args[1];
-	s_ip_idx = ip_idx = cb->args[2];
+	s_ip_idx = cb->args[2];
+
+	if (cb->strict_check) {
+		err = inet_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
+						 skb->sk, cb);
+		if (err < 0)
+			goto put_tgt_net;
+
+		err = 0;
+		if (fillargs.ifindex) {
+			dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
+			if (!dev) {
+				err = -ENODEV;
+				goto put_tgt_net;
+			}
+
+			in_dev = __in_dev_get_rtnl(dev);
+			if (in_dev) {
+				err = in_dev_dump_addr(in_dev, skb, cb, s_ip_idx,
+						       &fillargs);
+			}
+			goto put_tgt_net;
+		}
+	}
 
 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
 		idx = 0;
-		head = &net->dev_index_head[h];
+		head = &tgt_net->dev_index_head[h];
 		rcu_read_lock();
-		cb->seq = atomic_read(&net->ipv4.dev_addr_genid) ^
-			  net->dev_base_seq;
+		cb->seq = atomic_read(&tgt_net->ipv4.dev_addr_genid) ^
+			  tgt_net->dev_base_seq;
 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
 			if (idx < s_idx)
 				goto cont;
@@ -1675,18 +1859,11 @@
 			if (!in_dev)
 				goto cont;
 
-			for (ifa = in_dev->ifa_list, ip_idx = 0; ifa;
-			     ifa = ifa->ifa_next, ip_idx++) {
-				if (ip_idx < s_ip_idx)
-					continue;
-				if (inet_fill_ifaddr(skb, ifa,
-					     NETLINK_CB(cb->skb).portid,
-					     cb->nlh->nlmsg_seq,
-					     RTM_NEWADDR, NLM_F_MULTI) < 0) {
-					rcu_read_unlock();
-					goto done;
-				}
-				nl_dump_check_consistent(cb, nlmsg_hdr(skb));
+			err = in_dev_dump_addr(in_dev, skb, cb, s_ip_idx,
+					       &fillargs);
+			if (err < 0) {
+				rcu_read_unlock();
+				goto done;
 			}
 cont:
 			idx++;
@@ -1697,16 +1874,24 @@
 done:
 	cb->args[0] = h;
 	cb->args[1] = idx;
-	cb->args[2] = ip_idx;
+put_tgt_net:
+	if (fillargs.netnsid >= 0)
+		put_net(tgt_net);
 
-	return skb->len;
+	return skb->len ? : err;
 }
 
 static void rtmsg_ifa(int event, struct in_ifaddr *ifa, struct nlmsghdr *nlh,
 		      u32 portid)
 {
+	struct inet_fill_args fillargs = {
+		.portid = portid,
+		.seq = nlh ? nlh->nlmsg_seq : 0,
+		.event = event,
+		.flags = 0,
+		.netnsid = -1,
+	};
 	struct sk_buff *skb;
-	u32 seq = nlh ? nlh->nlmsg_seq : 0;
 	int err = -ENOBUFS;
 	struct net *net;
 
@@ -1715,7 +1900,7 @@
 	if (!skb)
 		goto errout;
 
-	err = inet_fill_ifaddr(skb, ifa, portid, seq, event, 0);
+	err = inet_fill_ifaddr(skb, ifa, &fillargs);
 	if (err < 0) {
 		/* -EMSGSIZE implies BUG in inet_nlmsg_size() */
 		WARN_ON(err == -EMSGSIZE);
@@ -1773,7 +1958,8 @@
 	if (dev && !__in_dev_get_rcu(dev))
 		return -EAFNOSUPPORT;
 
-	err = nla_parse_nested(tb, IFLA_INET_MAX, nla, inet_af_policy, NULL);
+	err = nla_parse_nested_deprecated(tb, IFLA_INET_MAX, nla,
+					  inet_af_policy, NULL);
 	if (err < 0)
 		return err;
 
@@ -1801,7 +1987,7 @@
 	if (!in_dev)
 		return -EAFNOSUPPORT;
 
-	if (nla_parse_nested(tb, IFLA_INET_MAX, nla, NULL, NULL) < 0)
+	if (nla_parse_nested_deprecated(tb, IFLA_INET_MAX, nla, NULL, NULL) < 0)
 		BUG();
 
 	if (tb[IFLA_INET_CONF]) {
@@ -1930,13 +2116,51 @@
 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
 };
 
+static int inet_netconf_valid_get_req(struct sk_buff *skb,
+				      const struct nlmsghdr *nlh,
+				      struct nlattr **tb,
+				      struct netlink_ext_ack *extack)
+{
+	int i, err;
+
+	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
+		NL_SET_ERR_MSG(extack, "ipv4: Invalid header for netconf get request");
+		return -EINVAL;
+	}
+
+	if (!netlink_strict_get_check(skb))
+		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
+					      tb, NETCONFA_MAX,
+					      devconf_ipv4_policy, extack);
+
+	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
+					    tb, NETCONFA_MAX,
+					    devconf_ipv4_policy, extack);
+	if (err)
+		return err;
+
+	for (i = 0; i <= NETCONFA_MAX; i++) {
+		if (!tb[i])
+			continue;
+
+		switch (i) {
+		case NETCONFA_IFINDEX:
+			break;
+		default:
+			NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in netconf get request");
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
 static int inet_netconf_get_devconf(struct sk_buff *in_skb,
 				    struct nlmsghdr *nlh,
 				    struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(in_skb->sk);
 	struct nlattr *tb[NETCONFA_MAX+1];
-	struct netconfmsg *ncm;
 	struct sk_buff *skb;
 	struct ipv4_devconf *devconf;
 	struct in_device *in_dev;
@@ -1944,9 +2168,8 @@
 	int ifindex;
 	int err;
 
-	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
-			  devconf_ipv4_policy, extack);
-	if (err < 0)
+	err = inet_netconf_valid_get_req(in_skb, nlh, tb, extack);
+	if (err)
 		goto errout;
 
 	err = -EINVAL;
@@ -1995,6 +2218,7 @@
 static int inet_netconf_dump_devconf(struct sk_buff *skb,
 				     struct netlink_callback *cb)
 {
+	const struct nlmsghdr *nlh = cb->nlh;
 	struct net *net = sock_net(skb->sk);
 	int h, s_h;
 	int idx, s_idx;
@@ -2002,6 +2226,21 @@
 	struct in_device *in_dev;
 	struct hlist_head *head;
 
+	if (cb->strict_check) {
+		struct netlink_ext_ack *extack = cb->extack;
+		struct netconfmsg *ncm;
+
+		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
+			NL_SET_ERR_MSG(extack, "ipv4: Invalid header for netconf dump request");
+			return -EINVAL;
+		}
+
+		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
+			NL_SET_ERR_MSG(extack, "ipv4: Invalid data after header in netconf dump request");
+			return -EINVAL;
+		}
+	}
+
 	s_h = cb->args[0];
 	s_idx = idx = cb->args[1];
 
@@ -2021,7 +2260,7 @@
 			if (inet_netconf_fill_devconf(skb, dev->ifindex,
 						      &in_dev->cnf,
 						      NETLINK_CB(cb->skb).portid,
-						      cb->nlh->nlmsg_seq,
+						      nlh->nlmsg_seq,
 						      RTM_NEWNETCONF,
 						      NLM_F_MULTI,
 						      NETCONFA_ALL) < 0) {
@@ -2038,7 +2277,7 @@
 		if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
 					      net->ipv4.devconf_all,
 					      NETLINK_CB(cb->skb).portid,
-					      cb->nlh->nlmsg_seq,
+					      nlh->nlmsg_seq,
 					      RTM_NEWNETCONF, NLM_F_MULTI,
 					      NETCONFA_ALL) < 0)
 			goto done;
@@ -2049,7 +2288,7 @@
 		if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
 					      net->ipv4.devconf_dflt,
 					      NETLINK_CB(cb->skb).portid,
-					      cb->nlh->nlmsg_seq,
+					      nlh->nlmsg_seq,
 					      RTM_NEWNETCONF, NLM_F_MULTI,
 					      NETCONFA_ALL) < 0)
 			goto done;
@@ -2407,32 +2646,34 @@
 	int err;
 	struct ipv4_devconf *all, *dflt;
 #ifdef CONFIG_SYSCTL
-	struct ctl_table *tbl = ctl_forward_entry;
+	struct ctl_table *tbl;
 	struct ctl_table_header *forw_hdr;
 #endif
 
 	err = -ENOMEM;
-	all = &ipv4_devconf;
-	dflt = &ipv4_devconf_dflt;
+	all = kmemdup(&ipv4_devconf, sizeof(ipv4_devconf), GFP_KERNEL);
+	if (!all)
+		goto err_alloc_all;
 
-	if (!net_eq(net, &init_net)) {
-		all = kmemdup(all, sizeof(ipv4_devconf), GFP_KERNEL);
-		if (!all)
-			goto err_alloc_all;
-
-		dflt = kmemdup(dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL);
-		if (!dflt)
-			goto err_alloc_dflt;
+	dflt = kmemdup(&ipv4_devconf_dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL);
+	if (!dflt)
+		goto err_alloc_dflt;
 
 #ifdef CONFIG_SYSCTL
-		tbl = kmemdup(tbl, sizeof(ctl_forward_entry), GFP_KERNEL);
-		if (!tbl)
-			goto err_alloc_ctl;
+	tbl = kmemdup(ctl_forward_entry, sizeof(ctl_forward_entry), GFP_KERNEL);
+	if (!tbl)
+		goto err_alloc_ctl;
 
-		tbl[0].data = &all->data[IPV4_DEVCONF_FORWARDING - 1];
-		tbl[0].extra1 = all;
-		tbl[0].extra2 = net;
+	tbl[0].data = &all->data[IPV4_DEVCONF_FORWARDING - 1];
+	tbl[0].extra1 = all;
+	tbl[0].extra2 = net;
 #endif
+
+	if ((!IS_ENABLED(CONFIG_SYSCTL) ||
+	     sysctl_devconf_inherit_init_net != 2) &&
+	    !net_eq(net, &init_net)) {
+		memcpy(all, init_net.ipv4.devconf_all, sizeof(ipv4_devconf));
+		memcpy(dflt, init_net.ipv4.devconf_dflt, sizeof(ipv4_devconf_dflt));
 	}
 
 #ifdef CONFIG_SYSCTL
@@ -2462,15 +2703,12 @@
 err_reg_dflt:
 	__devinet_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
 err_reg_all:
-	if (tbl != ctl_forward_entry)
-		kfree(tbl);
+	kfree(tbl);
 err_alloc_ctl:
 #endif
-	if (dflt != &ipv4_devconf_dflt)
-		kfree(dflt);
+	kfree(dflt);
 err_alloc_dflt:
-	if (all != &ipv4_devconf)
-		kfree(all);
+	kfree(all);
 err_alloc_all:
 	return err;
 }