diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c
index ec5ec68be1aa..0b3026b8fa40 100644
--- a/net/rxrpc/af_rxrpc.c
+++ b/net/rxrpc/af_rxrpc.c
@@ -762,6 +762,7 @@ static __poll_t rxrpc_poll(struct file *file, struct socket *sock,
 static int rxrpc_create(struct net *net, struct socket *sock, int protocol,
 			int kern)
 {
+	struct rxrpc_net *rxnet;
 	struct rxrpc_sock *rx;
 	struct sock *sk;
 
@@ -801,6 +802,9 @@ static int rxrpc_create(struct net *net, struct socket *sock, int protocol,
 	rwlock_init(&rx->call_lock);
 	memset(&rx->srx, 0, sizeof(rx->srx));
 
+	rxnet = rxrpc_net(sock_net(&rx->sk));
+	timer_reduce(&rxnet->peer_keepalive_timer, jiffies + 1);
+
 	_leave(" = 0 [%p]", rx);
 	return 0;
 }
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 21cf164b6d85..8a348e0a9d95 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -97,8 +97,16 @@ struct rxrpc_net {
 	struct list_head	local_endpoints;
 	struct mutex		local_mutex;	/* Lock for ->local_endpoints */
 
-	spinlock_t		peer_hash_lock;	/* Lock for ->peer_hash */
 	DECLARE_HASHTABLE	(peer_hash, 10);
+	spinlock_t		peer_hash_lock;	/* Lock for ->peer_hash */
+
+#define RXRPC_KEEPALIVE_TIME 20 /* NAT keepalive time in seconds */
+	u8			peer_keepalive_cursor;
+	ktime_t			peer_keepalive_base;
+	struct hlist_head	peer_keepalive[RXRPC_KEEPALIVE_TIME + 1];
+	struct hlist_head	peer_keepalive_new;
+	struct timer_list	peer_keepalive_timer;
+	struct work_struct	peer_keepalive_work;
 };
 
 /*
@@ -285,6 +293,8 @@ struct rxrpc_peer {
 	struct hlist_head	error_targets;	/* targets for net error distribution */
 	struct work_struct	error_distributor;
 	struct rb_root		service_conns;	/* Service connections */
+	struct hlist_node	keepalive_link;	/* Link in net->peer_keepalive[] */
+	time64_t		last_tx_at;	/* Last time packet sent here */
 	seqlock_t		service_conn_lock;
 	spinlock_t		lock;		/* access lock */
 	unsigned int		if_mtu;		/* interface MTU for this peer */
@@ -1026,6 +1036,7 @@ int rxrpc_send_ack_packet(struct rxrpc_call *, bool, rxrpc_serial_t *);
 int rxrpc_send_abort_packet(struct rxrpc_call *);
 int rxrpc_send_data_packet(struct rxrpc_call *, struct sk_buff *, bool);
 void rxrpc_reject_packets(struct rxrpc_local *);
+void rxrpc_send_keepalive(struct rxrpc_peer *);
 
 /*
  * peer_event.c
@@ -1034,6 +1045,7 @@ void rxrpc_error_report(struct sock *);
 void rxrpc_peer_error_distributor(struct work_struct *);
 void rxrpc_peer_add_rtt(struct rxrpc_call *, enum rxrpc_rtt_rx_trace,
 			rxrpc_serial_t, rxrpc_serial_t, ktime_t, ktime_t);
+void rxrpc_peer_keepalive_worker(struct work_struct *);
 
 /*
  * peer_object.c
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index d2ec3fd593e8..c717152070df 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -136,6 +136,7 @@ static void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn,
 	}
 
 	kernel_sendmsg(conn->params.local->socket, &msg, iov, ioc, len);
+	conn->params.peer->last_tx_at = ktime_get_real();
 	_leave("");
 	return;
 }
@@ -239,6 +240,8 @@ static int rxrpc_abort_connection(struct rxrpc_connection *conn,
 		return -EAGAIN;
 	}
 
+	conn->params.peer->last_tx_at = ktime_get_real();
+
 	_leave(" = 0");
 	return 0;
 }
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index 2a868fdab0ae..d4f2509e018b 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -1183,6 +1183,8 @@ void rxrpc_data_ready(struct sock *udp_sk)
 
 	switch (sp->hdr.type) {
 	case RXRPC_PACKET_TYPE_VERSION:
+		if (!(sp->hdr.flags & RXRPC_CLIENT_INITIATED))
+			goto discard;
 		rxrpc_post_packet_to_local(local, skb);
 		goto out;
 
diff --git a/net/rxrpc/net_ns.c b/net/rxrpc/net_ns.c
index f18c9248e0d4..66baf2b80b6c 100644
--- a/net/rxrpc/net_ns.c
+++ b/net/rxrpc/net_ns.c
@@ -32,13 +32,22 @@ static void rxrpc_service_conn_reap_timeout(struct timer_list *timer)
 		rxrpc_queue_work(&rxnet->service_conn_reaper);
 }
 
+static void rxrpc_peer_keepalive_timeout(struct timer_list *timer)
+{
+	struct rxrpc_net *rxnet =
+		container_of(timer, struct rxrpc_net, peer_keepalive_timer);
+
+	if (rxnet->live)
+		rxrpc_queue_work(&rxnet->peer_keepalive_work);
+}
+
 /*
  * Initialise a per-network namespace record.
  */
 static __net_init int rxrpc_init_net(struct net *net)
 {
 	struct rxrpc_net *rxnet = rxrpc_net(net);
-	int ret;
+	int ret, i;
 
 	rxnet->live = true;
 	get_random_bytes(&rxnet->epoch, sizeof(rxnet->epoch));
@@ -70,8 +79,16 @@ static __net_init int rxrpc_init_net(struct net *net)
 
 	INIT_LIST_HEAD(&rxnet->local_endpoints);
 	mutex_init(&rxnet->local_mutex);
+
 	hash_init(rxnet->peer_hash);
 	spin_lock_init(&rxnet->peer_hash_lock);
+	for (i = 0; i < ARRAY_SIZE(rxnet->peer_keepalive); i++)
+		INIT_HLIST_HEAD(&rxnet->peer_keepalive[i]);
+	INIT_HLIST_HEAD(&rxnet->peer_keepalive_new);
+	timer_setup(&rxnet->peer_keepalive_timer,
+		    rxrpc_peer_keepalive_timeout, 0);
+	INIT_WORK(&rxnet->peer_keepalive_work, rxrpc_peer_keepalive_worker);
+	rxnet->peer_keepalive_base = ktime_add(ktime_get_real(), NSEC_PER_SEC);
 
 	ret = -ENOMEM;
 	rxnet->proc_net = proc_net_mkdir(net, "rxrpc", net->proc_net);
@@ -95,6 +112,8 @@ static __net_exit void rxrpc_exit_net(struct net *net)
 	struct rxrpc_net *rxnet = rxrpc_net(net);
 
 	rxnet->live = false;
+	del_timer_sync(&rxnet->peer_keepalive_timer);
+	cancel_work_sync(&rxnet->peer_keepalive_work);
 	rxrpc_destroy_all_calls(rxnet);
 	rxrpc_destroy_all_connections(rxnet);
 	rxrpc_destroy_all_locals(rxnet);
diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index cf73dc006c3b..7f1fc04775b3 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c
@@ -32,6 +32,8 @@ struct rxrpc_abort_buffer {
 	__be32 abort_code;
 };
 
+static const char rxrpc_keepalive_string[] = "";
+
 /*
  * Arrange for a keepalive ping a certain time after we last transmitted.  This
  * lets the far side know we're still interested in this call and helps keep
@@ -122,6 +124,7 @@ int rxrpc_send_ack_packet(struct rxrpc_call *call, bool ping,
 	struct kvec iov[2];
 	rxrpc_serial_t serial;
 	rxrpc_seq_t hard_ack, top;
+	ktime_t now;
 	size_t len, n;
 	int ret;
 	u8 reason;
@@ -203,8 +206,10 @@ int rxrpc_send_ack_packet(struct rxrpc_call *call, bool ping,
 	}
 
 	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
+	now = ktime_get_real();
 	if (ping)
-		call->ping_time = ktime_get_real();
+		call->ping_time = now;
+	conn->params.peer->last_tx_at = ktime_get_real();
 
 	if (call->state < RXRPC_CALL_COMPLETE) {
 		if (ret < 0) {
@@ -288,6 +293,7 @@ int rxrpc_send_abort_packet(struct rxrpc_call *call)
 
 	ret = kernel_sendmsg(conn->params.local->socket,
 			     &msg, iov, 1, sizeof(pkt));
+	conn->params.peer->last_tx_at = ktime_get_real();
 
 	rxrpc_put_connection(conn);
 	return ret;
@@ -378,6 +384,7 @@ int rxrpc_send_data_packet(struct rxrpc_call *call, struct sk_buff *skb,
 	 *     message and update the peer record
 	 */
 	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
+	conn->params.peer->last_tx_at = ktime_get_real();
 
 	up_read(&conn->params.local->defrag_sem);
 	if (ret == -EMSGSIZE)
@@ -429,6 +436,7 @@ send_fragmentable:
 		if (ret == 0) {
 			ret = kernel_sendmsg(conn->params.local->socket, &msg,
 					     iov, 2, len);
+			conn->params.peer->last_tx_at = ktime_get_real();
 
 			opt = IP_PMTUDISC_DO;
 			kernel_setsockopt(conn->params.local->socket, SOL_IP,
@@ -446,6 +454,7 @@ send_fragmentable:
 		if (ret == 0) {
 			ret = kernel_sendmsg(conn->params.local->socket, &msg,
 					     iov, 2, len);
+			conn->params.peer->last_tx_at = ktime_get_real();
 
 			opt = IPV6_PMTUDISC_DO;
 			kernel_setsockopt(conn->params.local->socket,
@@ -515,3 +524,51 @@ void rxrpc_reject_packets(struct rxrpc_local *local)
 
 	_leave("");
 }
+
+/*
+ * Send a VERSION reply to a peer as a keepalive.
+ */
+void rxrpc_send_keepalive(struct rxrpc_peer *peer)
+{
+	struct rxrpc_wire_header whdr;
+	struct msghdr msg;
+	struct kvec iov[2];
+	size_t len;
+	int ret;
+
+	_enter("");
+
+	msg.msg_name	= &peer->srx.transport;
+	msg.msg_namelen	= peer->srx.transport_len;
+	msg.msg_control	= NULL;
+	msg.msg_controllen = 0;
+	msg.msg_flags	= 0;
+
+	whdr.epoch	= htonl(peer->local->rxnet->epoch);
+	whdr.cid	= 0;
+	whdr.callNumber	= 0;
+	whdr.seq	= 0;
+	whdr.serial	= 0;
+	whdr.type	= RXRPC_PACKET_TYPE_VERSION; /* Not client-initiated */
+	whdr.flags	= RXRPC_LAST_PACKET;
+	whdr.userStatus	= 0;
+	whdr.securityIndex = 0;
+	whdr._rsvd	= 0;
+	whdr.serviceId	= 0;
+
+	iov[0].iov_base	= &whdr;
+	iov[0].iov_len	= sizeof(whdr);
+	iov[1].iov_base	= (char *)rxrpc_keepalive_string;
+	iov[1].iov_len	= sizeof(rxrpc_keepalive_string);
+
+	len = iov[0].iov_len + iov[1].iov_len;
+
+	_proto("Tx VERSION (keepalive)");
+
+	ret = kernel_sendmsg(peer->local->socket, &msg, iov, 2, len);
+	if (ret < 0)
+		_debug("sendmsg failed: %d", ret);
+
+	peer->last_tx_at = ktime_get_real();
+	_leave("");
+}
diff --git a/net/rxrpc/peer_event.c b/net/rxrpc/peer_event.c
index 7f749505e699..d01eb9a06448 100644
--- a/net/rxrpc/peer_event.c
+++ b/net/rxrpc/peer_event.c
@@ -348,3 +348,99 @@ void rxrpc_peer_add_rtt(struct rxrpc_call *call, enum rxrpc_rtt_rx_trace why,
 	trace_rxrpc_rtt_rx(call, why, send_serial, resp_serial, rtt,
 			   usage, avg);
 }
+
+/*
+ * Perform keep-alive pings with VERSION packets to keep any NAT alive.
+ */
+void rxrpc_peer_keepalive_worker(struct work_struct *work)
+{
+	struct rxrpc_net *rxnet =
+		container_of(work, struct rxrpc_net, peer_keepalive_work);
+	struct rxrpc_peer *peer;
+	unsigned long delay;
+	ktime_t base, now = ktime_get_real();
+	s64 diff;
+	u8 cursor, slot;
+
+	base = rxnet->peer_keepalive_base;
+	cursor = rxnet->peer_keepalive_cursor;
+
+	_enter("%u,%lld", cursor, ktime_sub(now, base));
+
+next_bucket:
+	diff = ktime_to_ns(ktime_sub(now, base));
+	if (diff < 0)
+		goto resched;
+
+	_debug("at %u", cursor);
+	spin_lock_bh(&rxnet->peer_hash_lock);
+next_peer:
+	if (!rxnet->live) {
+		spin_unlock_bh(&rxnet->peer_hash_lock);
+		goto out;
+	}
+
+	/* Everything in the bucket at the cursor is processed this second; the
+	 * bucket at cursor + 1 goes now + 1s and so on...
+	 */
+	if (hlist_empty(&rxnet->peer_keepalive[cursor])) {
+		if (hlist_empty(&rxnet->peer_keepalive_new)) {
+			spin_unlock_bh(&rxnet->peer_hash_lock);
+			goto emptied_bucket;
+		}
+
+		hlist_move_list(&rxnet->peer_keepalive_new,
+				&rxnet->peer_keepalive[cursor]);
+	}
+
+	peer = hlist_entry(rxnet->peer_keepalive[cursor].first,
+			   struct rxrpc_peer, keepalive_link);
+	hlist_del_init(&peer->keepalive_link);
+	if (!rxrpc_get_peer_maybe(peer))
+		goto next_peer;
+
+	spin_unlock_bh(&rxnet->peer_hash_lock);
+
+	_debug("peer %u {%pISp}", peer->debug_id, &peer->srx.transport);
+
+recalc:
+	diff = ktime_divns(ktime_sub(peer->last_tx_at, base), NSEC_PER_SEC);
+	if (diff < -30 || diff > 30)
+		goto send; /* LSW of 64-bit time probably wrapped on 32-bit */
+	diff += RXRPC_KEEPALIVE_TIME - 1;
+	if (diff < 0)
+		goto send;
+
+	slot = (diff > RXRPC_KEEPALIVE_TIME - 1) ? RXRPC_KEEPALIVE_TIME - 1 : diff;
+	if (slot == 0)
+		goto send;
+
+	/* A transmission to this peer occurred since last we examined it so
+	 * put it into the appropriate future bucket.
+	 */
+	slot = (slot + cursor) % ARRAY_SIZE(rxnet->peer_keepalive);
+	spin_lock_bh(&rxnet->peer_hash_lock);
+	hlist_add_head(&peer->keepalive_link, &rxnet->peer_keepalive[slot]);
+	rxrpc_put_peer(peer);
+	goto next_peer;
+
+send:
+	rxrpc_send_keepalive(peer);
+	now = ktime_get_real();
+	goto recalc;
+
+emptied_bucket:
+	cursor++;
+	if (cursor >= ARRAY_SIZE(rxnet->peer_keepalive))
+		cursor = 0;
+	base = ktime_add_ns(base, NSEC_PER_SEC);
+	goto next_bucket;
+
+resched:
+	rxnet->peer_keepalive_base = base;
+	rxnet->peer_keepalive_cursor = cursor;
+	delay = nsecs_to_jiffies(-diff) + 1;
+	timer_reduce(&rxnet->peer_keepalive_timer, jiffies + delay);
+out:
+	_leave("");
+}
diff --git a/net/rxrpc/peer_object.c b/net/rxrpc/peer_object.c
index d02a99f37f5f..94a6dbfcf129 100644
--- a/net/rxrpc/peer_object.c
+++ b/net/rxrpc/peer_object.c
@@ -322,6 +322,7 @@ struct rxrpc_peer *rxrpc_lookup_incoming_peer(struct rxrpc_local *local,
 	if (!peer) {
 		peer = prealloc;
 		hash_add_rcu(rxnet->peer_hash, &peer->hash_link, hash_key);
+		hlist_add_head(&peer->keepalive_link, &rxnet->peer_keepalive_new);
 	}
 
 	spin_unlock(&rxnet->peer_hash_lock);
@@ -363,9 +364,12 @@ struct rxrpc_peer *rxrpc_lookup_peer(struct rxrpc_local *local,
 		peer = __rxrpc_lookup_peer_rcu(local, srx, hash_key);
 		if (peer && !rxrpc_get_peer_maybe(peer))
 			peer = NULL;
-		if (!peer)
+		if (!peer) {
 			hash_add_rcu(rxnet->peer_hash,
 				     &candidate->hash_link, hash_key);
+			hlist_add_head(&candidate->keepalive_link,
+				       &rxnet->peer_keepalive_new);
+		}
 
 		spin_unlock_bh(&rxnet->peer_hash_lock);
 
@@ -392,6 +396,7 @@ void __rxrpc_put_peer(struct rxrpc_peer *peer)
 
 	spin_lock_bh(&rxnet->peer_hash_lock);
 	hash_del_rcu(&peer->hash_link);
+	hlist_del_init(&peer->keepalive_link);
 	spin_unlock_bh(&rxnet->peer_hash_lock);
 
 	kfree_rcu(peer, rcu);
diff --git a/net/rxrpc/rxkad.c b/net/rxrpc/rxkad.c
index 77cb23c7bd0a..588fea0dd362 100644
--- a/net/rxrpc/rxkad.c
+++ b/net/rxrpc/rxkad.c
@@ -668,6 +668,7 @@ static int rxkad_issue_challenge(struct rxrpc_connection *conn)
 		return -EAGAIN;
 	}
 
+	conn->params.peer->last_tx_at = ktime_get_real();
 	_leave(" = 0");
 	return 0;
 }
@@ -722,6 +723,7 @@ static int rxkad_send_response(struct rxrpc_connection *conn,
 		return -EAGAIN;
 	}
 
+	conn->params.peer->last_tx_at = ktime_get_real();
 	_leave(" = 0");
 	return 0;
 }