diff --git a/libknet/transport_udp.c b/libknet/transport_udp.c
index e4e61648..25e1ae64 100644
--- a/libknet/transport_udp.c
+++ b/libknet/transport_udp.c
@@ -1,430 +1,433 @@
 /*
  * Copyright (C) 2016-2018 Red Hat, Inc.  All rights reserved.
  *
  * Author: Christine Caulfield <ccaulfie@redhat.com>
  *
  * This software licensed under GPL-2.0+, LGPL-2.0+
  */
 
 #include "config.h"
 
 #include <string.h>
 #include <unistd.h>
 #include <errno.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <stdlib.h>
 #include <netinet/in.h>
 #include <netinet/ip.h>
 #include <netinet/ip_icmp.h>
 #if defined (IP_RECVERR) || defined (IPV6_RECVERR)
 #include <linux/errqueue.h>
 #endif
 
 #include "libknet.h"
 #include "compat.h"
 #include "host.h"
 #include "link.h"
 #include "logging.h"
 #include "common.h"
 #include "transport_common.h"
 #include "transport_udp.h"
 #include "threads_common.h"
 
 typedef struct udp_handle_info {
 	struct knet_list_head links_list;
 } udp_handle_info_t;
 
 typedef struct udp_link_info {
 	struct knet_list_head list;
 	struct sockaddr_storage local_address;
 	int socket_fd;
 	int on_epoll;
 } udp_link_info_t;
 
 int udp_transport_link_set_config(knet_handle_t knet_h, struct knet_link *kn_link)
 {
 	int err = 0, savederrno = 0;
 	int sock = -1;
 	struct epoll_event ev;
 	udp_link_info_t *info;
 	udp_handle_info_t *handle_info = knet_h->transports[KNET_TRANSPORT_UDP];
 #if defined (IP_RECVERR) || defined (IPV6_RECVERR)
 	int value;
 #endif
 
 	/*
 	 * Only allocate a new link if the local address is different
 	 */
 	knet_list_for_each_entry(info, &handle_info->links_list, list) {
 		if (memcmp(&info->local_address, &kn_link->src_addr, sizeof(struct sockaddr_storage)) == 0) {
 			log_debug(knet_h, KNET_SUB_TRANSP_UDP, "Re-using existing UDP socket for new link");
 			kn_link->outsock = info->socket_fd;
 			kn_link->transport_link = info;
 			kn_link->transport_connected = 1;
 			return 0;
 		}
 	}
 
 	info = malloc(sizeof(udp_link_info_t));
 	if (!info) {
 		err = -1;
 		goto exit_error;
 	}
 
 	sock = socket(kn_link->src_addr.ss_family, SOCK_DGRAM, 0);
 	if (sock < 0) {
 		savederrno = errno;
 		err = -1;
 		log_err(knet_h, KNET_SUB_TRANSP_UDP, "Unable to create listener socket: %s",
 			strerror(savederrno));
 		goto exit_error;
 	}
 
 	if (_configure_transport_socket(knet_h, sock, &kn_link->src_addr, kn_link->flags, "UDP") < 0) {
 		savederrno = errno;
 		err = -1;
 		goto exit_error;
 	}
 
 #ifdef IP_RECVERR
 	if (kn_link->src_addr.ss_family == AF_INET) {
 		value = 1;
 		if (setsockopt(sock, SOL_IP, IP_RECVERR, &value, sizeof(value)) <0) {
 			savederrno = errno;
 			err = -1;
 			log_err(knet_h, KNET_SUB_TRANSP_UDP, "Unable to set RECVERR on socket: %s",
 				strerror(savederrno));
 			goto exit_error;
 		}
 		log_debug(knet_h, KNET_SUB_TRANSP_UDP, "IP_RECVERR enabled on socket: %i", sock);
 	}
 #else
 	log_debug(knet_h, KNET_SUB_TRANSP_UDP, "IP_RECVERR not available in this build/platform");
 #endif
 #ifdef IPV6_RECVERR
 	if (kn_link->src_addr.ss_family == AF_INET6) {
 		value = 1;
 		if (setsockopt(sock, SOL_IPV6, IPV6_RECVERR, &value, sizeof(value)) <0) {
 			savederrno = errno;
 			err = -1;
 			log_err(knet_h, KNET_SUB_TRANSP_UDP, "Unable to set RECVERR on socket: %s",
 				strerror(savederrno));
 			goto exit_error;
 		}
 		log_debug(knet_h, KNET_SUB_TRANSP_UDP, "IPV6_RECVERR enabled on socket: %i", sock);
 	}
 #else
 	log_debug(knet_h, KNET_SUB_TRANSP_UDP, "IPV6_RECVERR not available in this build/platform");
 #endif
 
 	if (bind(sock, (struct sockaddr *)&kn_link->src_addr, sockaddr_len(&kn_link->src_addr))) {
 		savederrno = errno;
 		err = -1;
 		log_err(knet_h, KNET_SUB_TRANSP_UDP, "Unable to bind listener socket: %s",
 			strerror(savederrno));
 		goto exit_error;
 	}
 
 	memset(&ev, 0, sizeof(struct epoll_event));
 	ev.events = EPOLLIN;
 	ev.data.fd = sock;
 
 	if (epoll_ctl(knet_h->recv_from_links_epollfd, EPOLL_CTL_ADD, sock, &ev)) {
 		savederrno = errno;
 		err = -1;
 		log_err(knet_h, KNET_SUB_TRANSP_UDP, "Unable to add listener to epoll pool: %s",
 			strerror(savederrno));
 		goto exit_error;
 	}
 
 	info->on_epoll = 1;
 
 	if (_set_fd_tracker(knet_h, sock, KNET_TRANSPORT_UDP, 0, info) < 0) {
 		savederrno = errno;
 		err = -1;
 		log_err(knet_h, KNET_SUB_TRANSP_UDP, "Unable to set fd tracker: %s",
 			strerror(savederrno));
 		goto exit_error;
 	}
 
 	memmove(&info->local_address, &kn_link->src_addr, sizeof(struct sockaddr_storage));
 	info->socket_fd = sock;
 	knet_list_add(&info->list, &handle_info->links_list);
 
 	kn_link->outsock = sock;
 	kn_link->transport_link = info;
 	kn_link->transport_connected = 1;
 
 exit_error:
 	if (err) {
 		if (info) {
 			if (info->on_epoll) {
 				epoll_ctl(knet_h->recv_from_links_epollfd, EPOLL_CTL_DEL, sock, &ev);
 			}
 			free(info);
 		}
 		if (sock >= 0) {
 			close(sock);
 		}
 	}
 	errno = savederrno;
 	return err;
 }
 
 int udp_transport_link_clear_config(knet_handle_t knet_h, struct knet_link *kn_link)
 {
 	int err = 0, savederrno = 0;
 	int found = 0;
 	struct knet_host *host;
 	int link_idx;
 	udp_link_info_t *info = kn_link->transport_link;
 	struct epoll_event ev;
 
 	for (host = knet_h->host_head; host != NULL; host = host->next) {
 		for (link_idx = 0; link_idx < KNET_MAX_LINK; link_idx++) {
 			if (&host->link[link_idx] == kn_link)
 				continue;
 
 			if ((host->link[link_idx].transport_link == info) &&
 			    (host->link[link_idx].status.enabled == 1)) {
 				found = 1;
 				break;
 			}
 		}
 	}
 
 	if (found) {
 		log_debug(knet_h, KNET_SUB_TRANSP_UDP, "UDP socket %d still in use", info->socket_fd);
 		savederrno = EBUSY;
 		err = -1;
 		goto exit_error;
 	}
 
 	if (info->on_epoll) {
 		memset(&ev, 0, sizeof(struct epoll_event));
 		ev.events = EPOLLIN;
 		ev.data.fd = info->socket_fd;
 
 		if (epoll_ctl(knet_h->recv_from_links_epollfd, EPOLL_CTL_DEL, info->socket_fd, &ev) < 0) {
 			savederrno = errno;
 			err = -1;
 			log_err(knet_h, KNET_SUB_TRANSP_UDP, "Unable to remove UDP socket from epoll poll: %s",
 				strerror(errno));
 			goto exit_error;
 		}
 		info->on_epoll = 0;
 	}
 
 	if (_set_fd_tracker(knet_h, info->socket_fd, KNET_MAX_TRANSPORTS, 0, NULL) < 0) {
 		savederrno = errno;
 		err = -1;
 		log_err(knet_h, KNET_SUB_TRANSP_UDP, "Unable to set fd tracker: %s",
 			strerror(savederrno));
 		goto exit_error;
 	}
 
 	close(info->socket_fd);
 	knet_list_del(&info->list);
 	free(kn_link->transport_link);
 
 exit_error:
 	errno = savederrno;
 	return err;
 }
 
 int udp_transport_free(knet_handle_t knet_h)
 {
 	udp_handle_info_t *handle_info;
 
 	if (!knet_h->transports[KNET_TRANSPORT_UDP]) {
 		errno = EINVAL;
 		return -1;
 	}
 
 	handle_info = knet_h->transports[KNET_TRANSPORT_UDP];
 
 	/*
 	 * keep it here while we debug list usage and such
 	 */
 	if (!knet_list_empty(&handle_info->links_list)) {
 		log_err(knet_h, KNET_SUB_TRANSP_UDP, "Internal error. handle list is not empty");
 		return -1;
 	}
 
 	free(handle_info);
 
 	knet_h->transports[KNET_TRANSPORT_UDP] = NULL;
 
 	return 0;
 }
 
 int udp_transport_init(knet_handle_t knet_h)
 {
 	udp_handle_info_t *handle_info;
 
 	if (knet_h->transports[KNET_TRANSPORT_UDP]) {
 		errno = EEXIST;
 		return -1;
 	}
 
 	handle_info = malloc(sizeof(udp_handle_info_t));
 	if (!handle_info) {
 		return -1;
 	}
 
 	memset(handle_info, 0, sizeof(udp_handle_info_t));
 
 	knet_h->transports[KNET_TRANSPORT_UDP] = handle_info;
 
 	knet_list_init(&handle_info->links_list);
 
 	return 0;
 }
 
 #if defined (IP_RECVERR) || defined (IPV6_RECVERR)
 static int read_errs_from_sock(knet_handle_t knet_h, int sockfd)
 {
 	int err = 0, savederrno = 0;
 	int got_err = 0;
 	char buffer[1024];
 	struct iovec iov;
 	struct msghdr msg;
 	struct cmsghdr *cmsg;
 	struct sock_extended_err *sock_err;
 	struct icmphdr icmph;
 	struct sockaddr_storage remote;
 	struct sockaddr_storage *origin;
 	char addr_str[KNET_MAX_HOST_LEN];
 	char port_str[KNET_MAX_PORT_LEN];
 
 	iov.iov_base = &icmph;
 	iov.iov_len = sizeof(icmph);
 	msg.msg_name = (void*)&remote;
 	msg.msg_namelen = sizeof(remote);
 	msg.msg_iov = &iov;
 	msg.msg_iovlen = 1;
 	msg.msg_flags = 0;
 	msg.msg_control = buffer;
 	msg.msg_controllen = sizeof(buffer);
 
 	for (;;) {
 		err = recvmsg(sockfd, &msg, MSG_ERRQUEUE);
 		savederrno = errno;
 		if (err < 0) {
 			if (!got_err) {
 				errno = savederrno;
 				return -1;
 			} else {
 				return 0;
 			}
 		}
 		got_err = 1;
 		for (cmsg = CMSG_FIRSTHDR(&msg);cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
 			if (((cmsg->cmsg_level == SOL_IP) && (cmsg->cmsg_type == IP_RECVERR)) ||
 			    ((cmsg->cmsg_level == SOL_IPV6 && (cmsg->cmsg_type == IPV6_RECVERR)))) {
 				sock_err = (struct sock_extended_err*)(void *)CMSG_DATA(cmsg);
 				if (sock_err) {
 					switch (sock_err->ee_origin) {
 						case 0: /* no origin */
 						case 1: /* local source (EMSGSIZE) */
 							if (sock_err->ee_errno == EMSGSIZE) {
 								if (pthread_mutex_lock(&knet_h->kmtu_mutex) != 0) {
 									log_debug(knet_h, KNET_SUB_TRANSP_UDP, "Unable to get mutex lock");
 									knet_h->kernel_mtu = 0;
 									break;
 								} else {
 									knet_h->kernel_mtu = sock_err->ee_info;
 									pthread_mutex_unlock(&knet_h->kmtu_mutex);
 								}
 
 								/*
 								 * we can only try to take a lock here. This part of the code
 								 * can be invoked by any thread, including PMTUd that is already
 								 * holding a lock at that stage.
 								 * If PMTUd is holding the lock, most likely it is already running
 								 * and we don't need to notify it back.
 								 */
 								if (!pthread_mutex_trylock(&knet_h->pmtud_mutex)) {
 									if (!knet_h->pmtud_running) {
 										if (!knet_h->pmtud_forcerun) {
 											log_debug(knet_h, KNET_SUB_TRANSP_UDP, "Notifying PMTUd to rerun");
 											knet_h->pmtud_forcerun = 1;
 										}
 									}
 									pthread_mutex_unlock(&knet_h->pmtud_mutex);
 								}
 							}
 							/*
 							 * those errors are way too noisy
 							 */
 							break;
 						case 2: /* ICMP */
 						case 3: /* ICMP6 */
 							origin = (struct sockaddr_storage *)(void *)SO_EE_OFFENDER(sock_err);
 							if (knet_addrtostr(origin, sizeof(origin),
 									   addr_str, KNET_MAX_HOST_LEN,
 									   port_str, KNET_MAX_PORT_LEN) < 0) {
 								log_debug(knet_h, KNET_SUB_TRANSP_UDP, "Received ICMP error from unknown source: %s", strerror(sock_err->ee_errno));
 
 							} else {
 								log_debug(knet_h, KNET_SUB_TRANSP_UDP, "Received ICMP error from %s: %s", addr_str, strerror(sock_err->ee_errno));
 							}
 							break;
 					}
 				} else {
 					log_debug(knet_h, KNET_SUB_TRANSP_UDP, "No data in MSG_ERRQUEUE");
 				}
 			}
 		}
 	}
 }
 #else
 static int read_errs_from_sock(knet_handle_t knet_h, int sockfd)
 {
 	return 0;
 }
 #endif
 
 int udp_transport_rx_sock_error(knet_handle_t knet_h, int sockfd, int recv_err, int recv_errno)
 {
 	if (recv_errno == EAGAIN) {
 		read_errs_from_sock(knet_h, sockfd);
 	}
 	return 0;
 }
 
 int udp_transport_tx_sock_error(knet_handle_t knet_h, int sockfd, int recv_err, int recv_errno)
 {
 	if (recv_err < 0) {
 		if (recv_errno == EMSGSIZE) {
 			read_errs_from_sock(knet_h, sockfd);
 			return 0;
 		}
+		if (recv_errno == EINVAL) {
+			return -1;
+		}
 		if ((recv_errno == ENOBUFS) || (recv_errno == EAGAIN)) {
 #ifdef DEBUG
 			log_debug(knet_h, KNET_SUB_TRANSP_UDP, "Sock: %d is overloaded. Slowing TX down", sockfd);
 #endif
 			usleep(KNET_THREADS_TIMERES / 16);
 		} else {
 			read_errs_from_sock(knet_h, sockfd);
 		}
 		return 1;
 	}
 
 	return 0;
 }
 
 int udp_transport_rx_is_data(knet_handle_t knet_h, int sockfd, struct knet_mmsghdr *msg)
 {
 	if (msg->msg_len == 0)
 		return 0;
 
 	return 2;
 }
 
 int udp_transport_link_dyn_connect(knet_handle_t knet_h, int sockfd, struct knet_link *kn_link)
 {
 	kn_link->status.dynconnected = 1;
 	return 0;
 }