Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 4e81ff2..34ccef1 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *	IPv6 Address [auto]configuration
  *	Linux INET6 implementation
@@ -5,11 +6,6 @@
  *	Authors:
  *	Pedro Roque		<roque@di.fc.ul.pt>
  *	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.
  */
 
 /*
@@ -173,13 +169,14 @@
 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
 						  int plen,
 						  const struct net_device *dev,
-						  u32 flags, u32 noflags);
+						  u32 flags, u32 noflags,
+						  bool no_gw);
 
 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
 static void addrconf_dad_work(struct work_struct *w);
 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
 				   bool send_na);
-static void addrconf_dad_run(struct inet6_dev *idev);
+static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
 static void addrconf_rs_timer(struct timer_list *t);
 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
@@ -481,7 +478,7 @@
 	if (!idev) {
 		idev = ipv6_add_dev(dev);
 		if (IS_ERR(idev))
-			return NULL;
+			return idev;
 	}
 
 	if (dev->flags&IFF_UP)
@@ -597,6 +594,45 @@
 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
 };
 
+static int inet6_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_MOD(extack, "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_ipv6_policy, extack);
+
+	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
+					    tb, NETCONFA_MAX,
+					    devconf_ipv6_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_MOD(extack, "Unsupported attribute in netconf get request");
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
 				     struct nlmsghdr *nlh,
 				     struct netlink_ext_ack *extack)
@@ -605,14 +641,12 @@
 	struct nlattr *tb[NETCONFA_MAX+1];
 	struct inet6_dev *in6_dev = NULL;
 	struct net_device *dev = NULL;
-	struct netconfmsg *ncm;
 	struct sk_buff *skb;
 	struct ipv6_devconf *devconf;
 	int ifindex;
 	int err;
 
-	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
-			  devconf_ipv6_policy, extack);
+	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
 	if (err < 0)
 		return err;
 
@@ -666,6 +700,7 @@
 static int inet6_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;
@@ -673,6 +708,21 @@
 	struct inet6_dev *idev;
 	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_MOD(extack, "Invalid header for netconf dump request");
+			return -EINVAL;
+		}
+
+		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
+			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
+			return -EINVAL;
+		}
+	}
+
 	s_h = cb->args[0];
 	s_idx = idx = cb->args[1];
 
@@ -692,7 +742,7 @@
 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
 						       &idev->cnf,
 						       NETLINK_CB(cb->skb).portid,
-						       cb->nlh->nlmsg_seq,
+						       nlh->nlmsg_seq,
 						       RTM_NEWNETCONF,
 						       NLM_F_MULTI,
 						       NETCONFA_ALL) < 0) {
@@ -709,7 +759,7 @@
 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
 					       net->ipv6.devconf_all,
 					       NETLINK_CB(cb->skb).portid,
-					       cb->nlh->nlmsg_seq,
+					       nlh->nlmsg_seq,
 					       RTM_NEWNETCONF, NLM_F_MULTI,
 					       NETCONFA_ALL) < 0)
 			goto done;
@@ -720,7 +770,7 @@
 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
 					       net->ipv6.devconf_dflt,
 					       NETLINK_CB(cb->skb).portid,
-					       cb->nlh->nlmsg_seq,
+					       nlh->nlmsg_seq,
 					       RTM_NEWNETCONF, NLM_F_MULTI,
 					       NETCONFA_ALL) < 0)
 			goto done;
@@ -995,8 +1045,10 @@
 	int err = 0;
 
 	if (addr_type == IPV6_ADDR_ANY ||
-	    addr_type & IPV6_ADDR_MULTICAST ||
+	    (addr_type & IPV6_ADDR_MULTICAST &&
+	     !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) ||
 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
+	     !netif_is_l3_master(idev->dev) &&
 	     addr_type & IPV6_ADDR_LOOPBACK))
 		return ERR_PTR(-EADDRNOTAVAIL);
 
@@ -1148,7 +1200,8 @@
 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
 		if (ifa == ifp)
 			continue;
-		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
+		if (ifa->prefix_len != ifp->prefix_len ||
+		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
 				       ifp->prefix_len))
 			continue;
 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
@@ -1177,10 +1230,8 @@
 {
 	struct fib6_info *f6i;
 
-	f6i = addrconf_get_prefix_route(&ifp->addr,
-				       ifp->prefix_len,
-				       ifp->idev->dev,
-				       0, RTF_GATEWAY | RTF_DEFAULT);
+	f6i = addrconf_get_prefix_route(&ifp->addr, ifp->prefix_len,
+					ifp->idev->dev, 0, RTF_DEFAULT, true);
 	if (f6i) {
 		if (del_rt)
 			ip6_del_rt(dev_net(ifp->idev->dev), f6i);
@@ -2349,7 +2400,8 @@
 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
 						  int plen,
 						  const struct net_device *dev,
-						  u32 flags, u32 noflags)
+						  u32 flags, u32 noflags,
+						  bool no_gw)
 {
 	struct fib6_node *fn;
 	struct fib6_info *rt = NULL;
@@ -2366,7 +2418,13 @@
 		goto out;
 
 	for_each_fib6_node_rt_rcu(fn) {
-		if (rt->fib6_nh.nh_dev->ifindex != dev->ifindex)
+		/* prefix routes only use builtin fib6_nh */
+		if (rt->nh)
+			continue;
+
+		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
+			continue;
+		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
 			continue;
 		if ((rt->fib6_flags & flags) != flags)
 			continue;
@@ -2408,8 +2466,8 @@
 	ASSERT_RTNL();
 
 	idev = ipv6_find_idev(dev);
-	if (!idev)
-		return ERR_PTR(-ENOBUFS);
+	if (IS_ERR(idev))
+		return idev;
 
 	if (idev->cnf.disable_ipv6)
 		return ERR_PTR(-EACCES);
@@ -2664,7 +2722,7 @@
 					       pinfo->prefix_len,
 					       dev,
 					       RTF_ADDRCONF | RTF_PREFIX_RT,
-					       RTF_GATEWAY | RTF_DEFAULT);
+					       RTF_DEFAULT, true);
 
 		if (rt) {
 			/* Autoconf prefix route */
@@ -2803,7 +2861,7 @@
 			dev = __dev_get_by_name(net, p.name);
 			if (!dev)
 				goto err_exit;
-			err = dev_open(dev);
+			err = dev_open(dev, NULL);
 		}
 	}
 #endif
@@ -3070,11 +3128,9 @@
 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
 		if (in_dev && (dev->flags & IFF_UP)) {
 			struct in_ifaddr *ifa;
-
 			int flag = scope;
 
-			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
-
+			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
 				addr.s6_addr32[3] = ifa->ifa_local;
 
 				if (ifa->ifa_scope == RT_SCOPE_LINK)
@@ -3103,7 +3159,7 @@
 	ASSERT_RTNL();
 
 	idev = ipv6_find_idev(dev);
-	if (!idev) {
+	if (IS_ERR(idev)) {
 		pr_debug("%s: add_dev failed\n", __func__);
 		return;
 	}
@@ -3318,7 +3374,7 @@
 	 */
 
 	idev = ipv6_find_idev(dev);
-	if (!idev) {
+	if (IS_ERR(idev)) {
 		pr_debug("%s: add_dev failed\n", __func__);
 		return;
 	}
@@ -3343,7 +3399,7 @@
 	ASSERT_RTNL();
 
 	idev = ipv6_find_idev(dev);
-	if (!idev) {
+	if (IS_ERR(idev)) {
 		pr_debug("%s: add_dev failed\n", __func__);
 		return;
 	}
@@ -3422,6 +3478,7 @@
 			   void *ptr)
 {
 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+	struct netdev_notifier_change_info *change_info;
 	struct netdev_notifier_changeupper_info *info;
 	struct inet6_dev *idev = __in6_dev_get(dev);
 	struct net *net = dev_net(dev);
@@ -3477,8 +3534,8 @@
 
 			if (!addrconf_link_ready(dev)) {
 				/* device is not ready yet. */
-				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
-					dev->name);
+				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
+					 dev->name);
 				break;
 			}
 
@@ -3496,7 +3553,7 @@
 				break;
 			}
 
-			if (idev) {
+			if (!IS_ERR_OR_NULL(idev)) {
 				if (idev->if_flags & IF_READY) {
 					/* device is already configured -
 					 * but resend MLD reports, we might
@@ -3504,6 +3561,9 @@
 					 * multicast snooping switches
 					 */
 					ipv6_mc_up(idev);
+					change_info = ptr;
+					if (change_info->flags_changed & IFF_NOARP)
+						addrconf_dad_run(idev, true);
 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
 					break;
 				}
@@ -3538,7 +3598,7 @@
 
 		if (!IS_ERR_OR_NULL(idev)) {
 			if (run_pending)
-				addrconf_dad_run(idev);
+				addrconf_dad_run(idev, false);
 
 			/* Device has an address by now */
 			rt6_sync_up(dev, RTNH_F_DEAD);
@@ -4156,16 +4216,19 @@
 		addrconf_verify_rtnl();
 }
 
-static void addrconf_dad_run(struct inet6_dev *idev)
+static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
 {
 	struct inet6_ifaddr *ifp;
 
 	read_lock_bh(&idev->lock);
 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
 		spin_lock(&ifp->lock);
-		if (ifp->flags & IFA_F_TENTATIVE &&
-		    ifp->state == INET6_IFADDR_STATE_DAD)
+		if ((ifp->flags & IFA_F_TENTATIVE &&
+		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
+			if (restart)
+				ifp->state = INET6_IFADDR_STATE_PREDAD;
 			addrconf_dad_kick(ifp);
+		}
 		spin_unlock(&ifp->lock);
 	}
 	read_unlock_bh(&idev->lock);
@@ -4489,6 +4552,7 @@
 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
 	[IFA_FLAGS]		= { .len = sizeof(u32) },
 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
+	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
 };
 
 static int
@@ -4502,8 +4566,8 @@
 	u32 ifa_flags;
 	int err;
 
-	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
-			  extack);
+	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
+				     ifa_ipv6_policy, extack);
 	if (err < 0)
 		return err;
 
@@ -4527,10 +4591,8 @@
 	struct fib6_info *f6i;
 	u32 prio;
 
-	f6i = addrconf_get_prefix_route(&ifp->addr,
-					ifp->prefix_len,
-					ifp->idev->dev,
-					0, RTF_GATEWAY | RTF_DEFAULT);
+	f6i = addrconf_get_prefix_route(&ifp->addr, ifp->prefix_len,
+					ifp->idev->dev, 0, RTF_DEFAULT, true);
 	if (!f6i)
 		return -ENOENT;
 
@@ -4668,8 +4730,8 @@
 	struct ifa6_config cfg;
 	int err;
 
-	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
-			  extack);
+	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
+				     ifa_ipv6_policy, extack);
 	if (err < 0)
 		return err;
 
@@ -4791,19 +4853,40 @@
 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
 }
 
+enum addr_type_t {
+	UNICAST_ADDR,
+	MULTICAST_ADDR,
+	ANYCAST_ADDR,
+};
+
+struct inet6_fill_args {
+	u32 portid;
+	u32 seq;
+	int event;
+	unsigned int flags;
+	int netnsid;
+	int ifindex;
+	enum addr_type_t type;
+};
+
 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
-			     u32 portid, u32 seq, int event, unsigned int flags)
+			     struct inet6_fill_args *args)
 {
 	struct nlmsghdr  *nlh;
 	u32 preferred, valid;
 
-	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
+	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
+			sizeof(struct ifaddrmsg), args->flags);
 	if (!nlh)
 		return -EMSGSIZE;
 
 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
 		      ifa->idev->dev->ifindex);
 
+	if (args->netnsid >= 0 &&
+	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
+		goto error;
+
 	if (!((ifa->flags&IFA_F_PERMANENT) &&
 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
 		preferred = ifa->prefered_lft;
@@ -4853,7 +4936,7 @@
 }
 
 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
-				u32 portid, u32 seq, int event, u16 flags)
+			       struct inet6_fill_args *args)
 {
 	struct nlmsghdr  *nlh;
 	u8 scope = RT_SCOPE_UNIVERSE;
@@ -4862,10 +4945,15 @@
 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
 		scope = RT_SCOPE_SITE;
 
-	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
+	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
+			sizeof(struct ifaddrmsg), args->flags);
 	if (!nlh)
 		return -EMSGSIZE;
 
+	if (args->netnsid >= 0 &&
+	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
+		return -EMSGSIZE;
+
 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
@@ -4879,7 +4967,7 @@
 }
 
 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
-				u32 portid, u32 seq, int event, unsigned int flags)
+			       struct inet6_fill_args *args)
 {
 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
 	int ifindex = dev ? dev->ifindex : 1;
@@ -4889,10 +4977,15 @@
 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
 		scope = RT_SCOPE_SITE;
 
-	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
+	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
+			sizeof(struct ifaddrmsg), args->flags);
 	if (!nlh)
 		return -EMSGSIZE;
 
+	if (args->netnsid >= 0 &&
+	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
+		return -EMSGSIZE;
+
 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
@@ -4905,36 +4998,27 @@
 	return 0;
 }
 
-enum addr_type_t {
-	UNICAST_ADDR,
-	MULTICAST_ADDR,
-	ANYCAST_ADDR,
-};
-
 /* called with rcu_read_lock() */
 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
-			  struct netlink_callback *cb, enum addr_type_t type,
-			  int s_ip_idx, int *p_ip_idx)
+			  struct netlink_callback *cb, int s_ip_idx,
+			  struct inet6_fill_args *fillargs)
 {
 	struct ifmcaddr6 *ifmca;
 	struct ifacaddr6 *ifaca;
+	int ip_idx = 0;
 	int err = 1;
-	int ip_idx = *p_ip_idx;
 
 	read_lock_bh(&idev->lock);
-	switch (type) {
+	switch (fillargs->type) {
 	case UNICAST_ADDR: {
 		struct inet6_ifaddr *ifa;
+		fillargs->event = RTM_NEWADDR;
 
 		/* unicast address incl. temp addr */
 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
 			if (ip_idx < s_ip_idx)
 				goto next;
-			err = inet6_fill_ifaddr(skb, ifa,
-						NETLINK_CB(cb->skb).portid,
-						cb->nlh->nlmsg_seq,
-						RTM_NEWADDR,
-						NLM_F_MULTI);
+			err = inet6_fill_ifaddr(skb, ifa, fillargs);
 			if (err < 0)
 				break;
 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
@@ -4944,31 +5028,26 @@
 		break;
 	}
 	case MULTICAST_ADDR:
+		fillargs->event = RTM_GETMULTICAST;
+
 		/* multicast address */
 		for (ifmca = idev->mc_list; ifmca;
 		     ifmca = ifmca->next, ip_idx++) {
 			if (ip_idx < s_ip_idx)
 				continue;
-			err = inet6_fill_ifmcaddr(skb, ifmca,
-						  NETLINK_CB(cb->skb).portid,
-						  cb->nlh->nlmsg_seq,
-						  RTM_GETMULTICAST,
-						  NLM_F_MULTI);
+			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
 			if (err < 0)
 				break;
 		}
 		break;
 	case ANYCAST_ADDR:
+		fillargs->event = RTM_GETANYCAST;
 		/* anycast address */
 		for (ifaca = idev->ac_list; ifaca;
 		     ifaca = ifaca->aca_next, ip_idx++) {
 			if (ip_idx < s_ip_idx)
 				continue;
-			err = inet6_fill_ifacaddr(skb, ifaca,
-						  NETLINK_CB(cb->skb).portid,
-						  cb->nlh->nlmsg_seq,
-						  RTM_GETANYCAST,
-						  NLM_F_MULTI);
+			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
 			if (err < 0)
 				break;
 		}
@@ -4977,42 +5056,130 @@
 		break;
 	}
 	read_unlock_bh(&idev->lock);
-	*p_ip_idx = ip_idx;
+	cb->args[2] = ip_idx;
 	return err;
 }
 
+static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
+				       struct inet6_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_MOD(extack, "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_MOD(extack, "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_ipv6_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_MOD(extack, "Invalid target network namespace id");
+				return PTR_ERR(net);
+			}
+			*tgt_net = net;
+		} else {
+			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
 			   enum addr_type_t type)
 {
+	const struct nlmsghdr *nlh = cb->nlh;
+	struct inet6_fill_args fillargs = {
+		.portid = NETLINK_CB(cb->skb).portid,
+		.seq = cb->nlh->nlmsg_seq,
+		.flags = NLM_F_MULTI,
+		.netnsid = -1,
+		.type = type,
+	};
 	struct net *net = sock_net(skb->sk);
+	struct net *tgt_net = net;
+	int idx, s_idx, s_ip_idx;
 	int h, s_h;
-	int idx, ip_idx;
-	int s_idx, s_ip_idx;
 	struct net_device *dev;
 	struct inet6_dev *idev;
 	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 = inet6_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;
+			}
+			idev = __in6_dev_get(dev);
+			if (idev) {
+				err = in6_dump_addrs(idev, skb, cb, s_ip_idx,
+						     &fillargs);
+				if (err > 0)
+					err = 0;
+			}
+			goto put_tgt_net;
+		}
+	}
 
 	rcu_read_lock();
-	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
+	cb->seq = atomic_read(&tgt_net->ipv6.dev_addr_genid) ^ tgt_net->dev_base_seq;
 	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];
 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
 			if (idx < s_idx)
 				goto cont;
 			if (h > s_h || idx > s_idx)
 				s_ip_idx = 0;
-			ip_idx = 0;
 			idev = __in6_dev_get(dev);
 			if (!idev)
 				goto cont;
 
-			if (in6_dump_addrs(idev, skb, cb, type,
-					   s_ip_idx, &ip_idx) < 0)
+			if (in6_dump_addrs(idev, skb, cb, s_ip_idx,
+					   &fillargs) < 0)
 				goto done;
 cont:
 			idx++;
@@ -5022,9 +5189,11 @@
 	rcu_read_unlock();
 	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 int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
@@ -5049,10 +5218,64 @@
 	return inet6_dump_addr(skb, cb, type);
 }
 
+static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
+				       const struct nlmsghdr *nlh,
+				       struct nlattr **tb,
+				       struct netlink_ext_ack *extack)
+{
+	struct ifaddrmsg *ifm;
+	int i, err;
+
+	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
+		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
+		return -EINVAL;
+	}
+
+	ifm = nlmsg_data(nlh);
+	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
+		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
+		return -EINVAL;
+	}
+
+	if (!netlink_strict_get_check(skb))
+		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
+					      ifa_ipv6_policy, extack);
+
+	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
+					    ifa_ipv6_policy, extack);
+	if (err)
+		return err;
+
+	for (i = 0; i <= IFA_MAX; i++) {
+		if (!tb[i])
+			continue;
+
+		switch (i) {
+		case IFA_TARGET_NETNSID:
+		case IFA_ADDRESS:
+		case IFA_LOCAL:
+			break;
+		default:
+			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
 			     struct netlink_ext_ack *extack)
 {
 	struct net *net = sock_net(in_skb->sk);
+	struct inet6_fill_args fillargs = {
+		.portid = NETLINK_CB(in_skb).portid,
+		.seq = nlh->nlmsg_seq,
+		.event = RTM_NEWADDR,
+		.flags = 0,
+		.netnsid = -1,
+	};
+	struct net *tgt_net = net;
 	struct ifaddrmsg *ifm;
 	struct nlattr *tb[IFA_MAX+1];
 	struct in6_addr *addr = NULL, *peer;
@@ -5061,20 +5284,28 @@
 	struct sk_buff *skb;
 	int err;
 
-	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
-			  extack);
+	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
 	if (err < 0)
 		return err;
 
+	if (tb[IFA_TARGET_NETNSID]) {
+		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
+
+		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
+						  fillargs.netnsid);
+		if (IS_ERR(tgt_net))
+			return PTR_ERR(tgt_net);
+	}
+
 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
 	if (!addr)
 		return -EINVAL;
 
 	ifm = nlmsg_data(nlh);
 	if (ifm->ifa_index)
-		dev = dev_get_by_index(net, ifm->ifa_index);
+		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
 
-	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
+	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
 	if (!ifa) {
 		err = -EADDRNOTAVAIL;
 		goto errout;
@@ -5086,20 +5317,22 @@
 		goto errout_ifa;
 	}
 
-	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
-				nlh->nlmsg_seq, RTM_NEWADDR, 0);
+	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
 	if (err < 0) {
 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
 		WARN_ON(err == -EMSGSIZE);
 		kfree_skb(skb);
 		goto errout_ifa;
 	}
-	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
+	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
 errout_ifa:
 	in6_ifa_put(ifa);
 errout:
 	if (dev)
 		dev_put(dev);
+	if (fillargs.netnsid >= 0)
+		put_net(tgt_net);
+
 	return err;
 }
 
@@ -5107,13 +5340,20 @@
 {
 	struct sk_buff *skb;
 	struct net *net = dev_net(ifa->idev->dev);
+	struct inet6_fill_args fillargs = {
+		.portid = 0,
+		.seq = 0,
+		.event = event,
+		.flags = 0,
+		.netnsid = -1,
+	};
 	int err = -ENOBUFS;
 
 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
 	if (!skb)
 		goto errout;
 
-	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
+	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
 	if (err < 0) {
 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
 		WARN_ON(err == -EMSGSIZE);
@@ -5420,18 +5660,6 @@
 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
 };
 
-static int inet6_validate_link_af(const struct net_device *dev,
-				  const struct nlattr *nla)
-{
-	struct nlattr *tb[IFLA_INET6_MAX + 1];
-
-	if (dev && !__in6_dev_get(dev))
-		return -EAFNOSUPPORT;
-
-	return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy,
-				NULL);
-}
-
 static int check_addr_gen_mode(int mode)
 {
 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
@@ -5452,16 +5680,46 @@
 	return 1;
 }
 
+static int inet6_validate_link_af(const struct net_device *dev,
+				  const struct nlattr *nla)
+{
+	struct nlattr *tb[IFLA_INET6_MAX + 1];
+	struct inet6_dev *idev = NULL;
+	int err;
+
+	if (dev) {
+		idev = __in6_dev_get(dev);
+		if (!idev)
+			return -EAFNOSUPPORT;
+	}
+
+	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
+					  inet6_af_policy, NULL);
+	if (err)
+		return err;
+
+	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
+		return -EINVAL;
+
+	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
+		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
+
+		if (check_addr_gen_mode(mode) < 0)
+			return -EINVAL;
+		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
 {
-	int err = -EINVAL;
 	struct inet6_dev *idev = __in6_dev_get(dev);
 	struct nlattr *tb[IFLA_INET6_MAX + 1];
+	int err;
 
-	if (!idev)
-		return -EAFNOSUPPORT;
-
-	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
+	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
 		BUG();
 
 	if (tb[IFLA_INET6_TOKEN]) {
@@ -5473,15 +5731,10 @@
 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
 
-		if (check_addr_gen_mode(mode) < 0 ||
-		    check_stable_privacy(idev, dev_net(dev), mode) < 0)
-			return -EINVAL;
-
 		idev->cnf.addr_gen_mode = mode;
-		err = 0;
 	}
 
-	return err;
+	return 0;
 }
 
 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
@@ -5513,7 +5766,7 @@
 	    nla_put_u8(skb, IFLA_OPERSTATE,
 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
 		goto nla_put_failure;
-	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
+	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
 	if (!protoinfo)
 		goto nla_put_failure;
 
@@ -5529,6 +5782,31 @@
 	return -EMSGSIZE;
 }
 
+static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
+				   struct netlink_ext_ack *extack)
+{
+	struct ifinfomsg *ifm;
+
+	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
+		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
+		return -EINVAL;
+	}
+
+	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
+		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
+		return -EINVAL;
+	}
+
+	ifm = nlmsg_data(nlh);
+	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
+	    ifm->ifi_change || ifm->ifi_index) {
+		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 {
 	struct net *net = sock_net(skb->sk);
@@ -5538,6 +5816,16 @@
 	struct inet6_dev *idev;
 	struct hlist_head *head;
 
+	/* only requests using strict checking can pass data to
+	 * influence the dump
+	 */
+	if (cb->strict_check) {
+		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
+
+		if (err < 0)
+			return err;
+	}
+
 	s_h = cb->args[0];
 	s_idx = cb->args[1];
 
@@ -5676,13 +5964,20 @@
 	switch (event) {
 	case RTM_NEWADDR:
 		/*
-		 * If the address was optimistic
-		 * we inserted the route at the start of
-		 * our DAD process, so we don't need
-		 * to do it again
+		 * If the address was optimistic we inserted the route at the
+		 * start of our DAD process, so we don't need to do it again.
+		 * If the device was taken down in the middle of the DAD
+		 * cycle there is a race where we could get here without a
+		 * host route, so nothing to insert. That will be fixed when
+		 * the device is brought up.
 		 */
-		if (!rcu_access_pointer(ifp->rt->fib6_node))
+		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
 			ip6_ins_rt(net, ifp->rt);
+		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
+			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
+				&ifp->addr, ifp->idev->dev->name);
+		}
+
 		if (ifp->idev->cnf.forwarding)
 			addrconf_join_anycast(ifp);
 		if (!ipv6_addr_any(&ifp->peer_addr))
@@ -5698,7 +5993,8 @@
 			struct fib6_info *rt;
 
 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
-						       ifp->idev->dev, 0, 0);
+						       ifp->idev->dev, 0, 0,
+						       false);
 			if (rt)
 				ip6_del_rt(net, rt);
 		}
@@ -6064,16 +6360,17 @@
 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
 		spin_lock(&ifa->lock);
 		if (ifa->rt) {
-			struct fib6_info *rt = ifa->rt;
+			/* host routes only use builtin fib6_nh */
+			struct fib6_nh *nh = ifa->rt->fib6_nh;
 			int cpu;
 
 			rcu_read_lock();
 			ifa->rt->dst_nopolicy = val ? true : false;
-			if (rt->rt6i_pcpu) {
+			if (nh->rt6i_pcpu) {
 				for_each_possible_cpu(cpu) {
 					struct rt6_info **rtp;
 
-					rtp = per_cpu_ptr(rt->rt6i_pcpu, cpu);
+					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
 					addrconf_set_nopolicy(*rtp, val);
 				}
 			}
@@ -6143,8 +6440,6 @@
 }
 
 static int minus_one = -1;
-static const int zero = 0;
-static const int one = 1;
 static const int two_five_five = 255;
 
 static const struct ctl_table addrconf_sysctl[] = {
@@ -6161,7 +6456,7 @@
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= (void *)&one,
+		.extra1		= (void *)SYSCTL_ONE,
 		.extra2		= (void *)&two_five_five,
 	},
 	{
@@ -6520,7 +6815,7 @@
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= (void *)&zero,
+		.extra1		= (void *)SYSCTL_ZERO,
 		.extra2		= (void *)&two_five_five,
 	},
 	{
@@ -6631,6 +6926,12 @@
 	if (!dflt)
 		goto err_alloc_dflt;
 
+	if (IS_ENABLED(CONFIG_SYSCTL) &&
+	    sysctl_devconf_inherit_init_net == 1 && !net_eq(net, &init_net)) {
+		memcpy(all, init_net.ipv6.devconf_all, sizeof(ipv6_devconf));
+		memcpy(dflt, init_net.ipv6.devconf_dflt, sizeof(ipv6_devconf_dflt));
+	}
+
 	/* these will be inherited by all namespaces */
 	dflt->autoconf = ipv6_defaults.autoconf;
 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;