--- zzzz-none-000/linux-4.4.271/net/ipv6/route.c	2021-06-03 06:22:09.000000000 +0000
+++ hawkeye-5590-750/linux-4.4.271/net/ipv6/route.c	2023-04-19 10:22:30.000000000 +0000
@@ -90,6 +90,8 @@
 static int		ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
 static int		ip6_pkt_prohibit(struct sk_buff *skb);
 static int		ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb);
+static int		ip6_pkt_policy_failed(struct sk_buff *skb);
+static int		ip6_pkt_policy_failed_out(struct net *net, struct sock *sk, struct sk_buff *skb);
 static void		ip6_link_failure(struct sk_buff *skb);
 static void		ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
 					   struct sk_buff *skb, u32 mtu);
@@ -177,6 +179,9 @@
 	return dst_metrics_write_ptr(rt->dst.from);
 }
 
+/* Define route change notification chain. */
+ATOMIC_NOTIFIER_HEAD(ip6route_chain);
+
 static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
 {
 	struct rt6_info *rt = (struct rt6_info *)dst;
@@ -299,6 +304,21 @@
 	.rt6i_ref	= ATOMIC_INIT(1),
 };
 
+static const struct rt6_info ip6_policy_failed_entry_template = {
+	.dst = {
+		.__refcnt	= ATOMIC_INIT(1),
+		.__use		= 1,
+		.obsolete	= DST_OBSOLETE_FORCE_CHK,
+		.error		= -EACCES,
+		.input		= ip6_pkt_policy_failed,
+		.output		= ip6_pkt_policy_failed_out,
+	},
+	.rt6i_flags	= (RTF_REJECT | RTF_NONEXTHOP),
+	.rt6i_protocol	= RTPROT_KERNEL,
+	.rt6i_metric	= ~(u32) 0,
+	.rt6i_ref	= ATOMIC_INIT(1),
+};
+
 static const struct rt6_info ip6_blk_hole_entry_template = {
 	.dst = {
 		.__refcnt	= ATOMIC_INIT(1),
@@ -395,14 +415,12 @@
 	struct net_device *loopback_dev =
 		dev_net(dev)->loopback_dev;
 
-	if (dev != loopback_dev) {
-		if (idev && idev->dev == dev) {
-			struct inet6_dev *loopback_idev =
-				in6_dev_get(loopback_dev);
-			if (loopback_idev) {
-				rt->rt6i_idev = loopback_idev;
-				in6_dev_put(idev);
-			}
+	if (idev && idev->dev != loopback_dev) {
+		struct inet6_dev *loopback_idev = in6_dev_get(loopback_dev);
+
+		if (loopback_idev) {
+			rt->rt6i_idev = loopback_idev;
+			in6_dev_put(idev);
 		}
 	}
 }
@@ -1401,7 +1419,7 @@
 }
 
 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
-		     int oif, u32 mark)
+		     int oif, u32 mark, kuid_t uid)
 {
 	const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
 	struct dst_entry *dst;
@@ -1413,6 +1431,7 @@
 	fl6.daddr = iph->daddr;
 	fl6.saddr = iph->saddr;
 	fl6.flowlabel = ip6_flowinfo(iph);
+	fl6.flowi6_uid = uid;
 
 	dst = ip6_route_output(net, NULL, &fl6);
 	if (!dst->error)
@@ -1428,7 +1447,7 @@
 	if (!oif && skb->dev)
 		oif = l3mdev_master_ifindex(skb->dev);
 
-	ip6_update_pmtu(skb, sock_net(sk), mtu, oif, sk->sk_mark);
+	ip6_update_pmtu(skb, sock_net(sk), mtu, oif, sk->sk_mark, sk->sk_uid);
 }
 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
 
@@ -1509,7 +1528,8 @@
 				flags, __ip6_route_redirect);
 }
 
-void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark)
+void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
+		  kuid_t uid)
 {
 	const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
 	struct dst_entry *dst;
@@ -1522,6 +1542,7 @@
 	fl6.daddr = iph->daddr;
 	fl6.saddr = iph->saddr;
 	fl6.flowlabel = ip6_flowinfo(iph);
+	fl6.flowi6_uid = uid;
 
 	dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
 	rt6_do_redirect(dst, NULL, skb);
@@ -1543,6 +1564,7 @@
 	fl6.flowi6_mark = mark;
 	fl6.daddr = msg->dest;
 	fl6.saddr = iph->daddr;
+	fl6.flowi6_uid = sock_net_uid(net, NULL);
 
 	dst = ip6_route_redirect(net, &fl6, &iph->saddr);
 	rt6_do_redirect(dst, NULL, skb);
@@ -1551,7 +1573,8 @@
 
 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
 {
-	ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark);
+	ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark,
+		     sk->sk_uid);
 }
 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
 
@@ -1909,6 +1932,11 @@
 			rt->dst.output = ip6_pkt_prohibit_out;
 			rt->dst.input = ip6_pkt_prohibit;
 			break;
+		case RTN_POLICY_FAILED:
+			rt->dst.error = -EACCES;
+			rt->dst.output = ip6_pkt_policy_failed_out;
+			rt->dst.input = ip6_pkt_policy_failed;
+			break;
 		case RTN_THROW:
 		case RTN_UNREACHABLE:
 		default:
@@ -2063,7 +2091,6 @@
 	write_lock_bh(&table->tb6_lock);
 	err = fib6_del(rt, info);
 	write_unlock_bh(&table->tb6_lock);
-
 out:
 	ip6_rt_put(rt);
 	return err;
@@ -2483,6 +2510,10 @@
 		}
 		rtnl_unlock();
 
+		if (!err)
+			atomic_notifier_call_chain(&ip6route_chain,
+						   SIOCADDRT ? RTM_NEWROUTE:RTM_DELROUTE, &cfg);
+
 		return err;
 	}
 
@@ -2538,6 +2569,17 @@
 	return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
 }
 
+static int ip6_pkt_policy_failed(struct sk_buff *skb)
+{
+	return ip6_pkt_drop(skb, ICMPV6_POLICY_FAIL, IPSTATS_MIB_INNOROUTES);
+}
+
+static int ip6_pkt_policy_failed_out(struct net *net, struct sock *sk, struct sk_buff *skb)
+{
+	skb->dev = skb_dst(skb)->dev;
+	return ip6_pkt_drop(skb, ICMPV6_POLICY_FAIL, IPSTATS_MIB_OUTNOROUTES);
+}
+
 /*
  *	Allocate a dst for local (unicast / anycast) address.
  */
@@ -2754,6 +2796,7 @@
 	[RTA_ENCAP_TYPE]	= { .type = NLA_U16 },
 	[RTA_ENCAP]		= { .type = NLA_NESTED },
 	[RTA_TABLE]		= { .type = NLA_U32 },
+	[RTA_UID]		= { .type = NLA_U32 },
 };
 
 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
@@ -2782,7 +2825,8 @@
 	if (rtm->rtm_type == RTN_UNREACHABLE ||
 	    rtm->rtm_type == RTN_BLACKHOLE ||
 	    rtm->rtm_type == RTN_PROHIBIT ||
-	    rtm->rtm_type == RTN_THROW)
+	    rtm->rtm_type == RTN_THROW ||
+	    rtm->rtm_type == RTN_POLICY_FAILED)
 		cfg->fc_flags |= RTF_REJECT;
 
 	if (rtm->rtm_type == RTN_LOCAL)
@@ -3057,9 +3101,15 @@
 		return err;
 
 	if (cfg.fc_mp)
-		return ip6_route_multipath_del(&cfg);
+		err = ip6_route_multipath_del(&cfg);
 	else
-		return ip6_route_del(&cfg);
+		err = ip6_route_del(&cfg);
+
+	if (!err)
+		atomic_notifier_call_chain(&ip6route_chain,
+					   RTM_DELROUTE, &cfg);
+
+	return err;
 }
 
 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
@@ -3072,9 +3122,15 @@
 		return err;
 
 	if (cfg.fc_mp)
-		return ip6_route_multipath_add(&cfg);
+		err = ip6_route_multipath_add(&cfg);
 	else
-		return ip6_route_add(&cfg);
+		err = ip6_route_add(&cfg);
+
+	if (!err)
+		atomic_notifier_call_chain(&ip6route_chain,
+					   RTM_NEWROUTE, &cfg);
+
+	return err;
 }
 
 static inline size_t rt6_nlmsg_size(struct rt6_info *rt)
@@ -3138,6 +3194,9 @@
 		case -EACCES:
 			rtm->rtm_type = RTN_PROHIBIT;
 			break;
+		case -EPERM:
+			rtm->rtm_type = RTN_POLICY_FAILED;
+			break;
 		case -EAGAIN:
 			rtm->rtm_type = RTN_THROW;
 			break;
@@ -3315,6 +3374,12 @@
 	if (tb[RTA_MARK])
 		fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
 
+	if (tb[RTA_UID])
+		fl6.flowi6_uid = make_kuid(current_user_ns(),
+					   nla_get_u32(tb[RTA_UID]));
+	else
+		fl6.flowi6_uid = iif ? INVALID_UID : current_uid();
+
 	if (iif) {
 		struct net_device *dev;
 		int flags = 0;
@@ -3417,6 +3482,8 @@
 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 		net->ipv6.ip6_prohibit_entry->dst.dev = dev;
 		net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
+		net->ipv6.ip6_policy_failed_entry->dst.dev = dev;
+		net->ipv6.ip6_policy_failed_entry->rt6i_idev = in6_dev_get(dev);
 		net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
 		net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
 #endif
@@ -3435,6 +3502,18 @@
 	return NOTIFY_OK;
 }
 
+int rt6_register_notifier(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_register(&ip6route_chain, nb);
+}
+EXPORT_SYMBOL(rt6_register_notifier);
+
+int rt6_unregister_notifier(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_unregister(&ip6route_chain, nb);
+}
+EXPORT_SYMBOL(rt6_unregister_notifier);
+
 /*
  *	/proc
  */
@@ -3643,6 +3722,17 @@
 	net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
 	dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
 			 ip6_template_metrics, true);
+
+	net->ipv6.ip6_policy_failed_entry =
+		kmemdup(&ip6_policy_failed_entry_template,
+			sizeof(*net->ipv6.ip6_policy_failed_entry), GFP_KERNEL);
+	if (!net->ipv6.ip6_policy_failed_entry)
+		goto out_ip6_blk_hole_entry;
+	net->ipv6.ip6_policy_failed_entry->dst.path =
+		(struct dst_entry *)net->ipv6.ip6_policy_failed_entry;
+	net->ipv6.ip6_policy_failed_entry->dst.ops = &net->ipv6.ip6_dst_ops;
+	dst_init_metrics(&net->ipv6.ip6_policy_failed_entry->dst,
+			 ip6_template_metrics, true);
 #endif
 
 	net->ipv6.sysctl.flush_delay = 0;
@@ -3661,6 +3751,8 @@
 	return ret;
 
 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
+out_ip6_blk_hole_entry:
+	kfree(net->ipv6.ip6_blk_hole_entry);
 out_ip6_prohibit_entry:
 	kfree(net->ipv6.ip6_prohibit_entry);
 out_ip6_null_entry:
@@ -3678,6 +3770,7 @@
 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 	kfree(net->ipv6.ip6_prohibit_entry);
 	kfree(net->ipv6.ip6_blk_hole_entry);
+	kfree(net->ipv6.ip6_policy_failed_entry);
 #endif
 	dst_entries_destroy(&net->ipv6.ip6_dst_ops);
 }
@@ -3751,6 +3844,9 @@
 	init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
 	init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
 	init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
+	init_net.ipv6.ip6_policy_failed_entry->dst.dev = init_net.loopback_dev;
+	init_net.ipv6.ip6_policy_failed_entry->rt6i_idev =
+		in6_dev_get(init_net.loopback_dev);
   #endif
 }