v4.19.13 snapshot.
diff --git a/net/rxrpc/local_object.c b/net/rxrpc/local_object.c
new file mode 100644
index 0000000..0906e51
--- /dev/null
+++ b/net/rxrpc/local_object.c
@@ -0,0 +1,498 @@
+/* Local endpoint object management
+ *
+ * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/net.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/udp.h>
+#include <linux/ip.h>
+#include <linux/hashtable.h>
+#include <net/sock.h>
+#include <net/udp.h>
+#include <net/af_rxrpc.h>
+#include "ar-internal.h"
+
+static void rxrpc_local_processor(struct work_struct *);
+static void rxrpc_local_rcu(struct rcu_head *);
+
+/*
+ * Compare a local to an address. Return -ve, 0 or +ve to indicate less than,
+ * same or greater than.
+ *
+ * We explicitly don't compare the RxRPC service ID as we want to reject
+ * conflicting uses by differing services. Further, we don't want to share
+ * addresses with different options (IPv6), so we don't compare those bits
+ * either.
+ */
+static long rxrpc_local_cmp_key(const struct rxrpc_local *local,
+ const struct sockaddr_rxrpc *srx)
+{
+ long diff;
+
+ diff = ((local->srx.transport_type - srx->transport_type) ?:
+ (local->srx.transport_len - srx->transport_len) ?:
+ (local->srx.transport.family - srx->transport.family));
+ if (diff != 0)
+ return diff;
+
+ switch (srx->transport.family) {
+ case AF_INET:
+ /* If the choice of UDP port is left up to the transport, then
+ * the endpoint record doesn't match.
+ */
+ return ((u16 __force)local->srx.transport.sin.sin_port -
+ (u16 __force)srx->transport.sin.sin_port) ?:
+ memcmp(&local->srx.transport.sin.sin_addr,
+ &srx->transport.sin.sin_addr,
+ sizeof(struct in_addr));
+#ifdef CONFIG_AF_RXRPC_IPV6
+ case AF_INET6:
+ /* If the choice of UDP6 port is left up to the transport, then
+ * the endpoint record doesn't match.
+ */
+ return ((u16 __force)local->srx.transport.sin6.sin6_port -
+ (u16 __force)srx->transport.sin6.sin6_port) ?:
+ memcmp(&local->srx.transport.sin6.sin6_addr,
+ &srx->transport.sin6.sin6_addr,
+ sizeof(struct in6_addr));
+#endif
+ default:
+ BUG();
+ }
+}
+
+/*
+ * Allocate a new local endpoint.
+ */
+static struct rxrpc_local *rxrpc_alloc_local(struct rxrpc_net *rxnet,
+ const struct sockaddr_rxrpc *srx)
+{
+ struct rxrpc_local *local;
+
+ local = kzalloc(sizeof(struct rxrpc_local), GFP_KERNEL);
+ if (local) {
+ atomic_set(&local->usage, 1);
+ local->rxnet = rxnet;
+ INIT_LIST_HEAD(&local->link);
+ INIT_WORK(&local->processor, rxrpc_local_processor);
+ init_rwsem(&local->defrag_sem);
+ skb_queue_head_init(&local->reject_queue);
+ skb_queue_head_init(&local->event_queue);
+ local->client_conns = RB_ROOT;
+ spin_lock_init(&local->client_conns_lock);
+ spin_lock_init(&local->lock);
+ rwlock_init(&local->services_lock);
+ local->debug_id = atomic_inc_return(&rxrpc_debug_id);
+ memcpy(&local->srx, srx, sizeof(*srx));
+ local->srx.srx_service = 0;
+ trace_rxrpc_local(local, rxrpc_local_new, 1, NULL);
+ }
+
+ _leave(" = %p", local);
+ return local;
+}
+
+/*
+ * create the local socket
+ * - must be called with rxrpc_local_mutex locked
+ */
+static int rxrpc_open_socket(struct rxrpc_local *local, struct net *net)
+{
+ struct sock *usk;
+ int ret, opt;
+
+ _enter("%p{%d,%d}",
+ local, local->srx.transport_type, local->srx.transport.family);
+
+ /* create a socket to represent the local endpoint */
+ ret = sock_create_kern(net, local->srx.transport.family,
+ local->srx.transport_type, 0, &local->socket);
+ if (ret < 0) {
+ _leave(" = %d [socket]", ret);
+ return ret;
+ }
+
+ /* set the socket up */
+ usk = local->socket->sk;
+ inet_sk(usk)->mc_loop = 0;
+
+ /* Enable CHECKSUM_UNNECESSARY to CHECKSUM_COMPLETE conversion */
+ inet_inc_convert_csum(usk);
+
+ rcu_assign_sk_user_data(usk, local);
+
+ udp_sk(usk)->encap_type = UDP_ENCAP_RXRPC;
+ udp_sk(usk)->encap_rcv = rxrpc_input_packet;
+ udp_sk(usk)->encap_destroy = NULL;
+ udp_sk(usk)->gro_receive = NULL;
+ udp_sk(usk)->gro_complete = NULL;
+
+ udp_encap_enable();
+#if IS_ENABLED(CONFIG_AF_RXRPC_IPV6)
+ if (local->srx.transport.family == AF_INET6)
+ udpv6_encap_enable();
+#endif
+ usk->sk_error_report = rxrpc_error_report;
+
+ /* if a local address was supplied then bind it */
+ if (local->srx.transport_len > sizeof(sa_family_t)) {
+ _debug("bind");
+ ret = kernel_bind(local->socket,
+ (struct sockaddr *)&local->srx.transport,
+ local->srx.transport_len);
+ if (ret < 0) {
+ _debug("bind failed %d", ret);
+ goto error;
+ }
+ }
+
+ switch (local->srx.transport.family) {
+ case AF_INET6:
+ /* we want to receive ICMPv6 errors */
+ opt = 1;
+ ret = kernel_setsockopt(local->socket, SOL_IPV6, IPV6_RECVERR,
+ (char *) &opt, sizeof(opt));
+ if (ret < 0) {
+ _debug("setsockopt failed");
+ goto error;
+ }
+
+ /* we want to set the don't fragment bit */
+ opt = IPV6_PMTUDISC_DO;
+ ret = kernel_setsockopt(local->socket, SOL_IPV6, IPV6_MTU_DISCOVER,
+ (char *) &opt, sizeof(opt));
+ if (ret < 0) {
+ _debug("setsockopt failed");
+ goto error;
+ }
+
+ /* Fall through and set IPv4 options too otherwise we don't get
+ * errors from IPv4 packets sent through the IPv6 socket.
+ */
+
+ case AF_INET:
+ /* we want to receive ICMP errors */
+ opt = 1;
+ ret = kernel_setsockopt(local->socket, SOL_IP, IP_RECVERR,
+ (char *) &opt, sizeof(opt));
+ if (ret < 0) {
+ _debug("setsockopt failed");
+ goto error;
+ }
+
+ /* we want to set the don't fragment bit */
+ opt = IP_PMTUDISC_DO;
+ ret = kernel_setsockopt(local->socket, SOL_IP, IP_MTU_DISCOVER,
+ (char *) &opt, sizeof(opt));
+ if (ret < 0) {
+ _debug("setsockopt failed");
+ goto error;
+ }
+
+ /* We want receive timestamps. */
+ opt = 1;
+ ret = kernel_setsockopt(local->socket, SOL_SOCKET, SO_TIMESTAMPNS,
+ (char *)&opt, sizeof(opt));
+ if (ret < 0) {
+ _debug("setsockopt failed");
+ goto error;
+ }
+ break;
+
+ default:
+ BUG();
+ }
+
+ _leave(" = 0");
+ return 0;
+
+error:
+ kernel_sock_shutdown(local->socket, SHUT_RDWR);
+ local->socket->sk->sk_user_data = NULL;
+ sock_release(local->socket);
+ local->socket = NULL;
+
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * Look up or create a new local endpoint using the specified local address.
+ */
+struct rxrpc_local *rxrpc_lookup_local(struct net *net,
+ const struct sockaddr_rxrpc *srx)
+{
+ struct rxrpc_local *local;
+ struct rxrpc_net *rxnet = rxrpc_net(net);
+ struct list_head *cursor;
+ const char *age;
+ long diff;
+ int ret;
+
+ _enter("{%d,%d,%pISp}",
+ srx->transport_type, srx->transport.family, &srx->transport);
+
+ mutex_lock(&rxnet->local_mutex);
+
+ for (cursor = rxnet->local_endpoints.next;
+ cursor != &rxnet->local_endpoints;
+ cursor = cursor->next) {
+ local = list_entry(cursor, struct rxrpc_local, link);
+
+ diff = rxrpc_local_cmp_key(local, srx);
+ if (diff < 0)
+ continue;
+ if (diff > 0)
+ break;
+
+ /* Services aren't allowed to share transport sockets, so
+ * reject that here. It is possible that the object is dying -
+ * but it may also still have the local transport address that
+ * we want bound.
+ */
+ if (srx->srx_service) {
+ local = NULL;
+ goto addr_in_use;
+ }
+
+ /* Found a match. We replace a dying object. Attempting to
+ * bind the transport socket may still fail if we're attempting
+ * to use a local address that the dying object is still using.
+ */
+ if (!rxrpc_get_local_maybe(local)) {
+ cursor = cursor->next;
+ list_del_init(&local->link);
+ break;
+ }
+
+ age = "old";
+ goto found;
+ }
+
+ local = rxrpc_alloc_local(rxnet, srx);
+ if (!local)
+ goto nomem;
+
+ ret = rxrpc_open_socket(local, net);
+ if (ret < 0)
+ goto sock_error;
+
+ list_add_tail(&local->link, cursor);
+ age = "new";
+
+found:
+ mutex_unlock(&rxnet->local_mutex);
+
+ _net("LOCAL %s %d {%pISp}",
+ age, local->debug_id, &local->srx.transport);
+
+ _leave(" = %p", local);
+ return local;
+
+nomem:
+ ret = -ENOMEM;
+sock_error:
+ mutex_unlock(&rxnet->local_mutex);
+ kfree(local);
+ _leave(" = %d", ret);
+ return ERR_PTR(ret);
+
+addr_in_use:
+ mutex_unlock(&rxnet->local_mutex);
+ _leave(" = -EADDRINUSE");
+ return ERR_PTR(-EADDRINUSE);
+}
+
+/*
+ * Get a ref on a local endpoint.
+ */
+struct rxrpc_local *rxrpc_get_local(struct rxrpc_local *local)
+{
+ const void *here = __builtin_return_address(0);
+ int n;
+
+ n = atomic_inc_return(&local->usage);
+ trace_rxrpc_local(local, rxrpc_local_got, n, here);
+ return local;
+}
+
+/*
+ * Get a ref on a local endpoint unless its usage has already reached 0.
+ */
+struct rxrpc_local *rxrpc_get_local_maybe(struct rxrpc_local *local)
+{
+ const void *here = __builtin_return_address(0);
+
+ if (local) {
+ int n = atomic_fetch_add_unless(&local->usage, 1, 0);
+ if (n > 0)
+ trace_rxrpc_local(local, rxrpc_local_got, n + 1, here);
+ else
+ local = NULL;
+ }
+ return local;
+}
+
+/*
+ * Queue a local endpoint.
+ */
+void rxrpc_queue_local(struct rxrpc_local *local)
+{
+ const void *here = __builtin_return_address(0);
+
+ if (rxrpc_queue_work(&local->processor))
+ trace_rxrpc_local(local, rxrpc_local_queued,
+ atomic_read(&local->usage), here);
+}
+
+/*
+ * A local endpoint reached its end of life.
+ */
+static void __rxrpc_put_local(struct rxrpc_local *local)
+{
+ _enter("%d", local->debug_id);
+ rxrpc_queue_work(&local->processor);
+}
+
+/*
+ * Drop a ref on a local endpoint.
+ */
+void rxrpc_put_local(struct rxrpc_local *local)
+{
+ const void *here = __builtin_return_address(0);
+ int n;
+
+ if (local) {
+ n = atomic_dec_return(&local->usage);
+ trace_rxrpc_local(local, rxrpc_local_put, n, here);
+
+ if (n == 0)
+ __rxrpc_put_local(local);
+ }
+}
+
+/*
+ * Destroy a local endpoint's socket and then hand the record to RCU to dispose
+ * of.
+ *
+ * Closing the socket cannot be done from bottom half context or RCU callback
+ * context because it might sleep.
+ */
+static void rxrpc_local_destroyer(struct rxrpc_local *local)
+{
+ struct socket *socket = local->socket;
+ struct rxrpc_net *rxnet = local->rxnet;
+
+ _enter("%d", local->debug_id);
+
+ /* We can get a race between an incoming call packet queueing the
+ * processor again and the work processor starting the destruction
+ * process which will shut down the UDP socket.
+ */
+ if (local->dead) {
+ _leave(" [already dead]");
+ return;
+ }
+ local->dead = true;
+
+ mutex_lock(&rxnet->local_mutex);
+ list_del_init(&local->link);
+ mutex_unlock(&rxnet->local_mutex);
+
+ ASSERT(RB_EMPTY_ROOT(&local->client_conns));
+ ASSERT(!local->service);
+
+ if (socket) {
+ local->socket = NULL;
+ kernel_sock_shutdown(socket, SHUT_RDWR);
+ socket->sk->sk_user_data = NULL;
+ sock_release(socket);
+ }
+
+ /* At this point, there should be no more packets coming in to the
+ * local endpoint.
+ */
+ rxrpc_purge_queue(&local->reject_queue);
+ rxrpc_purge_queue(&local->event_queue);
+
+ _debug("rcu local %d", local->debug_id);
+ call_rcu(&local->rcu, rxrpc_local_rcu);
+}
+
+/*
+ * Process events on an endpoint
+ */
+static void rxrpc_local_processor(struct work_struct *work)
+{
+ struct rxrpc_local *local =
+ container_of(work, struct rxrpc_local, processor);
+ bool again;
+
+ trace_rxrpc_local(local, rxrpc_local_processing,
+ atomic_read(&local->usage), NULL);
+
+ do {
+ again = false;
+ if (atomic_read(&local->usage) == 0)
+ return rxrpc_local_destroyer(local);
+
+ if (!skb_queue_empty(&local->reject_queue)) {
+ rxrpc_reject_packets(local);
+ again = true;
+ }
+
+ if (!skb_queue_empty(&local->event_queue)) {
+ rxrpc_process_local_events(local);
+ again = true;
+ }
+ } while (again);
+}
+
+/*
+ * Destroy a local endpoint after the RCU grace period expires.
+ */
+static void rxrpc_local_rcu(struct rcu_head *rcu)
+{
+ struct rxrpc_local *local = container_of(rcu, struct rxrpc_local, rcu);
+
+ _enter("%d", local->debug_id);
+
+ ASSERT(!work_pending(&local->processor));
+
+ _net("DESTROY LOCAL %d", local->debug_id);
+ kfree(local);
+ _leave("");
+}
+
+/*
+ * Verify the local endpoint list is empty by this point.
+ */
+void rxrpc_destroy_all_locals(struct rxrpc_net *rxnet)
+{
+ struct rxrpc_local *local;
+
+ _enter("");
+
+ flush_workqueue(rxrpc_workqueue);
+
+ if (!list_empty(&rxnet->local_endpoints)) {
+ mutex_lock(&rxnet->local_mutex);
+ list_for_each_entry(local, &rxnet->local_endpoints, link) {
+ pr_err("AF_RXRPC: Leaked local %p {%d}\n",
+ local, atomic_read(&local->usage));
+ }
+ mutex_unlock(&rxnet->local_mutex);
+ BUG();
+ }
+}