--- zzzz-none-000/linux-4.9.276/net/ipv4/tcp_ipv4.c	2021-07-20 14:21:16.000000000 +0000
+++ falcon-5530-750/linux-4.9.276/net/ipv4/tcp_ipv4.c	2023-04-05 08:19:02.000000000 +0000
@@ -84,6 +84,8 @@
 #include <crypto/hash.h>
 #include <linux/scatterlist.h>
 
+#include <avm/pa/avm_pa.h>
+
 int sysctl_tcp_tw_reuse __read_mostly;
 int sysctl_tcp_low_latency __read_mostly;
 
@@ -446,7 +448,7 @@
 			if (!sock_owned_by_user(sk)) {
 				tcp_v4_mtu_reduced(sk);
 			} else {
-				if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, &tp->tsq_flags))
+				if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, &sk->sk_tsq_flags))
 					sock_hold(sk);
 			}
 			goto out;
@@ -696,6 +698,7 @@
 		     offsetof(struct inet_timewait_sock, tw_bound_dev_if));
 
 	arg.tos = ip_hdr(skb)->tos;
+	arg.uid = sock_net_uid(net, sk && sk_fullsock(sk) ? sk : NULL);
 	local_bh_disable();
 	ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
 			      skb, &TCP_SKB_CB(skb)->header.h4.opt,
@@ -716,7 +719,7 @@
    outside socket context is ugly, certainly. What can I do?
  */
 
-static void tcp_v4_send_ack(struct net *net,
+static void tcp_v4_send_ack(const struct sock *sk,
 			    struct sk_buff *skb, u32 seq, u32 ack,
 			    u32 win, u32 tsval, u32 tsecr, int oif,
 			    struct tcp_md5sig_key *key,
@@ -731,6 +734,7 @@
 #endif
 			];
 	} rep;
+	struct net *net = sock_net(sk);
 	struct ip_reply_arg arg;
 
 	memset(&rep.th, 0, sizeof(struct tcphdr));
@@ -780,6 +784,7 @@
 	if (oif)
 		arg.bound_dev_if = oif;
 	arg.tos = tos;
+	arg.uid = sock_net_uid(net, sk_fullsock(sk) ? sk : NULL);
 	local_bh_disable();
 	ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
 			      skb, &TCP_SKB_CB(skb)->header.h4.opt,
@@ -795,7 +800,7 @@
 	struct inet_timewait_sock *tw = inet_twsk(sk);
 	struct tcp_timewait_sock *tcptw = tcp_twsk(sk);
 
-	tcp_v4_send_ack(sock_net(sk), skb,
+	tcp_v4_send_ack(sk, skb,
 			tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt,
 			tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale,
 			tcp_time_stamp + tcptw->tw_ts_offset,
@@ -823,7 +828,7 @@
 	 * exception of <SYN> segments, MUST be right-shifted by
 	 * Rcv.Wind.Shift bits:
 	 */
-	tcp_v4_send_ack(sock_net(sk), skb, seq,
+	tcp_v4_send_ack(sk, skb, seq,
 			tcp_rsk(req)->rcv_nxt,
 			req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale,
 			tcp_time_stamp,
@@ -1598,6 +1603,32 @@
 }
 EXPORT_SYMBOL(tcp_filter);
 
+static void tcp_v4_restore_cb(struct sk_buff *skb)
+{
+	memmove(IPCB(skb), &TCP_SKB_CB(skb)->header.h4,
+		sizeof(struct inet_skb_parm));
+}
+
+static void tcp_v4_fill_cb(struct sk_buff *skb, const struct iphdr *iph,
+			   const struct tcphdr *th)
+{
+	/* This is tricky : We move IPCB at its correct location into TCP_SKB_CB()
+	 * barrier() makes sure compiler wont play fool^Waliasing games.
+	 */
+	memmove(&TCP_SKB_CB(skb)->header.h4, IPCB(skb),
+		sizeof(struct inet_skb_parm));
+	barrier();
+
+	TCP_SKB_CB(skb)->seq = ntohl(th->seq);
+	TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin +
+				    skb->len - th->doff * 4);
+	TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq);
+	TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th);
+	TCP_SKB_CB(skb)->tcp_tw_isn = 0;
+	TCP_SKB_CB(skb)->ip_dsfield = ipv4_get_dsfield(iph);
+	TCP_SKB_CB(skb)->sacked	 = 0;
+}
+
 /*
  *	From tcp_input.c
  */
@@ -1637,22 +1668,6 @@
 
 	th = (const struct tcphdr *)skb->data;
 	iph = ip_hdr(skb);
-	/* This is tricky : We move IPCB at its correct location into TCP_SKB_CB()
-	 * barrier() makes sure compiler wont play fool^Waliasing games.
-	 */
-	memmove(&TCP_SKB_CB(skb)->header.h4, IPCB(skb),
-		sizeof(struct inet_skb_parm));
-	barrier();
-
-	TCP_SKB_CB(skb)->seq = ntohl(th->seq);
-	TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin +
-				    skb->len - th->doff * 4);
-	TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq);
-	TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th);
-	TCP_SKB_CB(skb)->tcp_tw_isn = 0;
-	TCP_SKB_CB(skb)->ip_dsfield = ipv4_get_dsfield(iph);
-	TCP_SKB_CB(skb)->sacked	 = 0;
-
 lookup:
 	sk = __inet_lookup_skb(&tcp_hashinfo, skb, __tcp_hdrlen(th), th->source,
 			       th->dest, &refcounted);
@@ -1660,6 +1675,8 @@
 		goto no_tcp_socket;
 
 process:
+	avm_pa_add_local_session(AVM_PA_NET_IP_DEVINFO(net), skb, sk);
+
 	if (sk->sk_state == TCP_TIME_WAIT)
 		goto do_time_wait;
 
@@ -1686,6 +1703,9 @@
 		 */
 		sock_hold(sk);
 		refcounted = true;
+		th = (const struct tcphdr *)skb->data;
+		iph = ip_hdr(skb);
+		tcp_v4_fill_cb(skb, iph, th);
 		nsk = tcp_check_req(sk, skb, req, false);
 		if (!nsk) {
 			reqsk_put(req);
@@ -1693,6 +1713,7 @@
 		}
 		if (nsk == sk) {
 			reqsk_put(req);
+			tcp_v4_restore_cb(skb);
 		} else if (tcp_child_process(sk, nsk, skb)) {
 			tcp_v4_send_reset(nsk, skb);
 			goto discard_and_relse;
@@ -1718,6 +1739,7 @@
 		goto discard_and_relse;
 	th = (const struct tcphdr *)skb->data;
 	iph = ip_hdr(skb);
+	tcp_v4_fill_cb(skb, iph, th);
 
 	skb->dev = NULL;
 
@@ -1749,6 +1771,8 @@
 	if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
 		goto discard_it;
 
+	tcp_v4_fill_cb(skb, iph, th);
+
 	if (tcp_checksum_complete(skb)) {
 csum_error:
 		__TCP_INC_STATS(net, TCP_MIB_CSUMERRORS);
@@ -1775,6 +1799,8 @@
 		goto discard_it;
 	}
 
+	tcp_v4_fill_cb(skb, iph, th);
+
 	if (tcp_checksum_complete(skb)) {
 		inet_twsk_put(inet_twsk(sk));
 		goto csum_error;
@@ -1790,6 +1816,7 @@
 		if (sk2) {
 			inet_twsk_deschedule_put(inet_twsk(sk));
 			sk = sk2;
+			tcp_v4_restore_cb(skb);
 			refcounted = false;
 			goto process;
 		}