--- zzzz-none-000/linux-4.4.60/net/ipv4/ip_output.c	2017-04-08 07:53:53.000000000 +0000
+++ scorpion-7490-727/linux-4.4.60/net/ipv4/ip_output.c	2021-02-04 17:41:59.000000000 +0000
@@ -80,6 +80,10 @@
 #include <linux/netlink.h>
 #include <linux/tcp.h>
 
+#ifdef CONFIG_AVM_PA
+#include <avm/pa/avm_pa.h>
+#endif
+
 int sysctl_ip_default_ttl __read_mostly = IPDEFTTL;
 EXPORT_SYMBOL(sysctl_ip_default_ttl);
 
@@ -103,6 +107,14 @@
 	iph->tot_len = htons(skb->len);
 	ip_send_check(iph);
 
+#ifdef CONFIG_AVM_PA
+	/* Someone must set AVM_PKT_INFO(skb)->local_out_pid_handle beforehand
+	 * to have a session.
+	 */
+	if (avm_pa_local_out_receive(skb, sk, AF_INET) == AVM_PA_RX_STOLEN)
+		return 0;
+#endif
+
 	skb->protocol = htons(ETH_P_IP);
 
 	return nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT,
@@ -486,6 +498,9 @@
 #ifdef CONFIG_NET_SCHED
 	to->tc_index = from->tc_index;
 #endif
+#ifdef CONFIG_AVM_PA
+	memcpy(AVM_PKT_INFO(to), AVM_PKT_INFO(from), sizeof(*AVM_PKT_INFO(to)));
+#endif
 	nf_copy(to, from);
 #if defined(CONFIG_IP_VS) || defined(CONFIG_IP_VS_MODULE)
 	to->ipvs_property = from->ipvs_property;
@@ -922,10 +937,12 @@
 		csummode = CHECKSUM_PARTIAL;
 
 	cork->length += length;
-	if (((length > mtu) || (skb && skb_is_gso(skb))) &&
+	if ((skb && skb_is_gso(skb)) ||
+	    (((length + (skb ? skb->len : fragheaderlen)) > mtu) &&
+	    (skb_queue_len(queue) <= 1) &&
 	    (sk->sk_protocol == IPPROTO_UDP) &&
-	    (rt->dst.dev->features & NETIF_F_UFO) && !rt->dst.header_len &&
-	    (sk->sk_type == SOCK_DGRAM) && !sk->sk_no_check_tx) {
+	    (rt->dst.dev->features & NETIF_F_UFO) && !dst_xfrm(&rt->dst) &&
+	    (sk->sk_type == SOCK_DGRAM) && !sk->sk_no_check_tx)) {
 		err = ip_ufo_append_data(sk, queue, getfrag, from, length,
 					 hh_len, fragheaderlen, transhdrlen,
 					 maxfraglen, flags);
@@ -1241,6 +1258,7 @@
 		return -EINVAL;
 
 	if ((size + skb->len > mtu) &&
+	    (skb_queue_len(&sk->sk_write_queue) == 1) &&
 	    (sk->sk_protocol == IPPROTO_UDP) &&
 	    (rt->dst.dev->features & NETIF_F_UFO)) {
 		if (skb->ip_summed != CHECKSUM_PARTIAL)