--- zzzz-none-000/linux-4.4.271/net/ipv4/route.c	2021-06-03 06:22:09.000000000 +0000
+++ maple-fsgw-759/linux-4.4.271/net/ipv4/route.c	2023-12-20 10:37:40.000000000 +0000
@@ -422,6 +422,9 @@
 
 static int __init ip_rt_proc_init(void)
 {
+	if (IS_ENABLED(CONFIG_PROC_STRIPPED))
+		return 0;
+
 	return register_pernet_subsys(&ip_rt_proc_ops);
 }
 
@@ -457,7 +460,7 @@
 	else if (skb)
 		pkey = &ip_hdr(skb)->daddr;
 
-	n = __ipv4_neigh_lookup(dev, *(__force u32 *)pkey);
+	n = __ipv4_neigh_lookup(dev, net_hdr_word(pkey));
 	if (n)
 		return n;
 	return neigh_create(&arp_tbl, pkey, dev);
@@ -509,7 +512,8 @@
 }
 EXPORT_SYMBOL(__ip_select_ident);
 
-static void __build_flow_key(struct flowi4 *fl4, const struct sock *sk,
+static void __build_flow_key(const struct net *net, struct flowi4 *fl4,
+			     const struct sock *sk,
 			     const struct iphdr *iph,
 			     int oif, u8 tos,
 			     u8 prot, u32 mark, int flow_flags)
@@ -525,19 +529,21 @@
 	flowi4_init_output(fl4, oif, mark, tos,
 			   RT_SCOPE_UNIVERSE, prot,
 			   flow_flags,
-			   iph->daddr, iph->saddr, 0, 0);
+			   iph->daddr, iph->saddr, 0, 0,
+			   sock_net_uid(net, sk));
 }
 
 static void build_skb_flow_key(struct flowi4 *fl4, const struct sk_buff *skb,
 			       const struct sock *sk)
 {
+	const struct net *net = dev_net(skb->dev);
 	const struct iphdr *iph = ip_hdr(skb);
 	int oif = skb->dev->ifindex;
 	u8 tos = RT_TOS(iph->tos);
 	u8 prot = iph->protocol;
 	u32 mark = skb->mark;
 
-	__build_flow_key(fl4, sk, iph, oif, tos, prot, mark, 0);
+	__build_flow_key(net, fl4, sk, iph, oif, tos, prot, mark, 0);
 }
 
 static void build_sk_flow_key(struct flowi4 *fl4, const struct sock *sk)
@@ -554,7 +560,7 @@
 			   RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE,
 			   inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol,
 			   inet_sk_flowi_flags(sk),
-			   daddr, inet->inet_saddr, 0, 0);
+			   daddr, inet->inet_saddr, 0, 0, sk->sk_uid);
 	rcu_read_unlock();
 }
 
@@ -813,7 +819,7 @@
 
 	rt = (struct rtable *) dst;
 
-	__build_flow_key(&fl4, sk, iph, oif, tos, prot, mark, 0);
+	__build_flow_key(sock_net(sk), &fl4, sk, iph, oif, tos, prot, mark, 0);
 	__ip_do_redirect(rt, skb, &fl4, true);
 }
 
@@ -1037,7 +1043,7 @@
 	if (!mark)
 		mark = IP4_REPLY_MARK(net, skb->mark);
 
-	__build_flow_key(&fl4, NULL, iph, oif,
+	__build_flow_key(net, &fl4, NULL, iph, oif,
 			 RT_TOS(iph->tos), protocol, mark, flow_flags);
 	rt = __ip_route_output_key(net, &fl4);
 	if (!IS_ERR(rt)) {
@@ -1053,7 +1059,7 @@
 	struct flowi4 fl4;
 	struct rtable *rt;
 
-	__build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0);
+	__build_flow_key(sock_net(sk), &fl4, sk, iph, 0, 0, 0, 0, 0);
 
 	if (!fl4.flowi4_mark)
 		fl4.flowi4_mark = IP4_REPLY_MARK(sock_net(sk), skb->mark);
@@ -1072,6 +1078,7 @@
 	struct rtable *rt;
 	struct dst_entry *odst = NULL;
 	bool new = false;
+	struct net *net = sock_net(sk);
 
 	bh_lock_sock(sk);
 
@@ -1085,7 +1092,7 @@
 		goto out;
 	}
 
-	__build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0);
+	__build_flow_key(net, &fl4, sk, iph, 0, 0, 0, 0, 0);
 
 	rt = (struct rtable *)odst;
 	if (odst->obsolete && !odst->ops->check(odst, 0)) {
@@ -1125,7 +1132,7 @@
 	struct flowi4 fl4;
 	struct rtable *rt;
 
-	__build_flow_key(&fl4, NULL, iph, oif,
+	__build_flow_key(net, &fl4, NULL, iph, oif,
 			 RT_TOS(iph->tos), protocol, mark, flow_flags);
 	rt = __ip_route_output_key(net, &fl4);
 	if (!IS_ERR(rt)) {
@@ -1140,9 +1147,10 @@
 	const struct iphdr *iph = (const struct iphdr *) skb->data;
 	struct flowi4 fl4;
 	struct rtable *rt;
+	struct net *net = sock_net(sk);
 
-	__build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0);
-	rt = __ip_route_output_key(sock_net(sk), &fl4);
+	__build_flow_key(net, &fl4, sk, iph, 0, 0, 0, 0, 0);
+	rt = __ip_route_output_key(net, &fl4);
 	if (!IS_ERR(rt)) {
 		__ip_do_redirect(rt, skb, &fl4, false);
 		ip_rt_put(rt);
@@ -2558,6 +2566,11 @@
 	    nla_put_u32(skb, RTA_MARK, fl4->flowi4_mark))
 		goto nla_put_failure;
 
+	if (!uid_eq(fl4->flowi4_uid, INVALID_UID) &&
+	    nla_put_u32(skb, RTA_UID,
+			from_kuid_munged(current_user_ns(), fl4->flowi4_uid)))
+		goto nla_put_failure;
+
 	error = rt->dst.error;
 
 	if (rt_is_input_route(rt)) {
@@ -2610,6 +2623,7 @@
 	int mark;
 	struct sk_buff *skb;
 	u32 table_id = RT_TABLE_MAIN;
+	kuid_t uid;
 
 	err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy);
 	if (err < 0)
@@ -2637,6 +2651,10 @@
 	dst = tb[RTA_DST] ? nla_get_in_addr(tb[RTA_DST]) : 0;
 	iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0;
 	mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0;
+	if (tb[RTA_UID])
+		uid = make_kuid(current_user_ns(), nla_get_u32(tb[RTA_UID]));
+	else
+		uid = (iif ? INVALID_UID : current_uid());
 
 	memset(&fl4, 0, sizeof(fl4));
 	fl4.daddr = dst;
@@ -2644,6 +2662,7 @@
 	fl4.flowi4_tos = rtm->rtm_tos;
 	fl4.flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0;
 	fl4.flowi4_mark = mark;
+	fl4.flowi4_uid = uid;
 
 	if (netif_index_is_l3_master(net, fl4.flowi4_oif))
 		fl4.flowi4_flags = FLOWI_FLAG_L3MDEV_SRC | FLOWI_FLAG_SKIP_NH_OIF;