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-rw-r--r--net/rxrpc/io_thread.c560
1 files changed, 560 insertions, 0 deletions
diff --git a/net/rxrpc/io_thread.c b/net/rxrpc/io_thread.c
new file mode 100644
index 0000000000..4a3a08a0e2
--- /dev/null
+++ b/net/rxrpc/io_thread.c
@@ -0,0 +1,560 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* RxRPC packet reception
+ *
+ * Copyright (C) 2007, 2016, 2022 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include "ar-internal.h"
+
+static int rxrpc_input_packet_on_conn(struct rxrpc_connection *conn,
+ struct sockaddr_rxrpc *peer_srx,
+ struct sk_buff *skb);
+
+/*
+ * handle data received on the local endpoint
+ * - may be called in interrupt context
+ *
+ * [!] Note that as this is called from the encap_rcv hook, the socket is not
+ * held locked by the caller and nothing prevents sk_user_data on the UDP from
+ * being cleared in the middle of processing this function.
+ *
+ * Called with the RCU read lock held from the IP layer via UDP.
+ */
+int rxrpc_encap_rcv(struct sock *udp_sk, struct sk_buff *skb)
+{
+ struct sk_buff_head *rx_queue;
+ struct rxrpc_local *local = rcu_dereference_sk_user_data(udp_sk);
+
+ if (unlikely(!local)) {
+ kfree_skb(skb);
+ return 0;
+ }
+ if (skb->tstamp == 0)
+ skb->tstamp = ktime_get_real();
+
+ skb->mark = RXRPC_SKB_MARK_PACKET;
+ rxrpc_new_skb(skb, rxrpc_skb_new_encap_rcv);
+ rx_queue = &local->rx_queue;
+#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
+ if (rxrpc_inject_rx_delay ||
+ !skb_queue_empty(&local->rx_delay_queue)) {
+ skb->tstamp = ktime_add_ms(skb->tstamp, rxrpc_inject_rx_delay);
+ rx_queue = &local->rx_delay_queue;
+ }
+#endif
+
+ skb_queue_tail(rx_queue, skb);
+ rxrpc_wake_up_io_thread(local);
+ return 0;
+}
+
+/*
+ * Handle an error received on the local endpoint.
+ */
+void rxrpc_error_report(struct sock *sk)
+{
+ struct rxrpc_local *local;
+ struct sk_buff *skb;
+
+ rcu_read_lock();
+ local = rcu_dereference_sk_user_data(sk);
+ if (unlikely(!local)) {
+ rcu_read_unlock();
+ return;
+ }
+
+ while ((skb = skb_dequeue(&sk->sk_error_queue))) {
+ skb->mark = RXRPC_SKB_MARK_ERROR;
+ rxrpc_new_skb(skb, rxrpc_skb_new_error_report);
+ skb_queue_tail(&local->rx_queue, skb);
+ }
+
+ rxrpc_wake_up_io_thread(local);
+ rcu_read_unlock();
+}
+
+/*
+ * Directly produce an abort from a packet.
+ */
+bool rxrpc_direct_abort(struct sk_buff *skb, enum rxrpc_abort_reason why,
+ s32 abort_code, int err)
+{
+ struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+
+ trace_rxrpc_abort(0, why, sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
+ abort_code, err);
+ skb->mark = RXRPC_SKB_MARK_REJECT_ABORT;
+ skb->priority = abort_code;
+ return false;
+}
+
+static bool rxrpc_bad_message(struct sk_buff *skb, enum rxrpc_abort_reason why)
+{
+ return rxrpc_direct_abort(skb, why, RX_PROTOCOL_ERROR, -EBADMSG);
+}
+
+#define just_discard true
+
+/*
+ * Process event packets targeted at a local endpoint.
+ */
+static bool rxrpc_input_version(struct rxrpc_local *local, struct sk_buff *skb)
+{
+ struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+ char v;
+
+ _enter("");
+
+ rxrpc_see_skb(skb, rxrpc_skb_see_version);
+ if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header), &v, 1) >= 0) {
+ if (v == 0)
+ rxrpc_send_version_request(local, &sp->hdr, skb);
+ }
+
+ return true;
+}
+
+/*
+ * Extract the wire header from a packet and translate the byte order.
+ */
+static bool rxrpc_extract_header(struct rxrpc_skb_priv *sp,
+ struct sk_buff *skb)
+{
+ struct rxrpc_wire_header whdr;
+
+ /* dig out the RxRPC connection details */
+ if (skb_copy_bits(skb, 0, &whdr, sizeof(whdr)) < 0)
+ return rxrpc_bad_message(skb, rxrpc_badmsg_short_hdr);
+
+ memset(sp, 0, sizeof(*sp));
+ sp->hdr.epoch = ntohl(whdr.epoch);
+ sp->hdr.cid = ntohl(whdr.cid);
+ sp->hdr.callNumber = ntohl(whdr.callNumber);
+ sp->hdr.seq = ntohl(whdr.seq);
+ sp->hdr.serial = ntohl(whdr.serial);
+ sp->hdr.flags = whdr.flags;
+ sp->hdr.type = whdr.type;
+ sp->hdr.userStatus = whdr.userStatus;
+ sp->hdr.securityIndex = whdr.securityIndex;
+ sp->hdr._rsvd = ntohs(whdr._rsvd);
+ sp->hdr.serviceId = ntohs(whdr.serviceId);
+ return true;
+}
+
+/*
+ * Extract the abort code from an ABORT packet and stash it in skb->priority.
+ */
+static bool rxrpc_extract_abort(struct sk_buff *skb)
+{
+ __be32 wtmp;
+
+ if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header),
+ &wtmp, sizeof(wtmp)) < 0)
+ return false;
+ skb->priority = ntohl(wtmp);
+ return true;
+}
+
+/*
+ * Process packets received on the local endpoint
+ */
+static bool rxrpc_input_packet(struct rxrpc_local *local, struct sk_buff **_skb)
+{
+ struct rxrpc_connection *conn;
+ struct sockaddr_rxrpc peer_srx;
+ struct rxrpc_skb_priv *sp;
+ struct rxrpc_peer *peer = NULL;
+ struct sk_buff *skb = *_skb;
+ bool ret = false;
+
+ skb_pull(skb, sizeof(struct udphdr));
+
+ sp = rxrpc_skb(skb);
+
+ /* dig out the RxRPC connection details */
+ if (!rxrpc_extract_header(sp, skb))
+ return just_discard;
+
+ if (IS_ENABLED(CONFIG_AF_RXRPC_INJECT_LOSS)) {
+ static int lose;
+ if ((lose++ & 7) == 7) {
+ trace_rxrpc_rx_lose(sp);
+ return just_discard;
+ }
+ }
+
+ trace_rxrpc_rx_packet(sp);
+
+ switch (sp->hdr.type) {
+ case RXRPC_PACKET_TYPE_VERSION:
+ if (rxrpc_to_client(sp))
+ return just_discard;
+ return rxrpc_input_version(local, skb);
+
+ case RXRPC_PACKET_TYPE_BUSY:
+ if (rxrpc_to_server(sp))
+ return just_discard;
+ fallthrough;
+ case RXRPC_PACKET_TYPE_ACK:
+ case RXRPC_PACKET_TYPE_ACKALL:
+ if (sp->hdr.callNumber == 0)
+ return rxrpc_bad_message(skb, rxrpc_badmsg_zero_call);
+ break;
+ case RXRPC_PACKET_TYPE_ABORT:
+ if (!rxrpc_extract_abort(skb))
+ return just_discard; /* Just discard if malformed */
+ break;
+
+ case RXRPC_PACKET_TYPE_DATA:
+ if (sp->hdr.callNumber == 0)
+ return rxrpc_bad_message(skb, rxrpc_badmsg_zero_call);
+ if (sp->hdr.seq == 0)
+ return rxrpc_bad_message(skb, rxrpc_badmsg_zero_seq);
+
+ /* Unshare the packet so that it can be modified for in-place
+ * decryption.
+ */
+ if (sp->hdr.securityIndex != 0) {
+ skb = skb_unshare(skb, GFP_ATOMIC);
+ if (!skb) {
+ rxrpc_eaten_skb(*_skb, rxrpc_skb_eaten_by_unshare_nomem);
+ *_skb = NULL;
+ return just_discard;
+ }
+
+ if (skb != *_skb) {
+ rxrpc_eaten_skb(*_skb, rxrpc_skb_eaten_by_unshare);
+ *_skb = skb;
+ rxrpc_new_skb(skb, rxrpc_skb_new_unshared);
+ sp = rxrpc_skb(skb);
+ }
+ }
+ break;
+
+ case RXRPC_PACKET_TYPE_CHALLENGE:
+ if (rxrpc_to_server(sp))
+ return just_discard;
+ break;
+ case RXRPC_PACKET_TYPE_RESPONSE:
+ if (rxrpc_to_client(sp))
+ return just_discard;
+ break;
+
+ /* Packet types 9-11 should just be ignored. */
+ case RXRPC_PACKET_TYPE_PARAMS:
+ case RXRPC_PACKET_TYPE_10:
+ case RXRPC_PACKET_TYPE_11:
+ return just_discard;
+
+ default:
+ return rxrpc_bad_message(skb, rxrpc_badmsg_unsupported_packet);
+ }
+
+ if (sp->hdr.serviceId == 0)
+ return rxrpc_bad_message(skb, rxrpc_badmsg_zero_service);
+
+ if (WARN_ON_ONCE(rxrpc_extract_addr_from_skb(&peer_srx, skb) < 0))
+ return just_discard; /* Unsupported address type. */
+
+ if (peer_srx.transport.family != local->srx.transport.family &&
+ (peer_srx.transport.family == AF_INET &&
+ local->srx.transport.family != AF_INET6)) {
+ pr_warn_ratelimited("AF_RXRPC: Protocol mismatch %u not %u\n",
+ peer_srx.transport.family,
+ local->srx.transport.family);
+ return just_discard; /* Wrong address type. */
+ }
+
+ if (rxrpc_to_client(sp)) {
+ rcu_read_lock();
+ conn = rxrpc_find_client_connection_rcu(local, &peer_srx, skb);
+ conn = rxrpc_get_connection_maybe(conn, rxrpc_conn_get_call_input);
+ rcu_read_unlock();
+ if (!conn)
+ return rxrpc_protocol_error(skb, rxrpc_eproto_no_client_conn);
+
+ ret = rxrpc_input_packet_on_conn(conn, &peer_srx, skb);
+ rxrpc_put_connection(conn, rxrpc_conn_put_call_input);
+ return ret;
+ }
+
+ /* We need to look up service connections by the full protocol
+ * parameter set. We look up the peer first as an intermediate step
+ * and then the connection from the peer's tree.
+ */
+ rcu_read_lock();
+
+ peer = rxrpc_lookup_peer_rcu(local, &peer_srx);
+ if (!peer) {
+ rcu_read_unlock();
+ return rxrpc_new_incoming_call(local, NULL, NULL, &peer_srx, skb);
+ }
+
+ conn = rxrpc_find_service_conn_rcu(peer, skb);
+ conn = rxrpc_get_connection_maybe(conn, rxrpc_conn_get_call_input);
+ if (conn) {
+ rcu_read_unlock();
+ ret = rxrpc_input_packet_on_conn(conn, &peer_srx, skb);
+ rxrpc_put_connection(conn, rxrpc_conn_put_call_input);
+ return ret;
+ }
+
+ peer = rxrpc_get_peer_maybe(peer, rxrpc_peer_get_input);
+ rcu_read_unlock();
+
+ ret = rxrpc_new_incoming_call(local, peer, NULL, &peer_srx, skb);
+ rxrpc_put_peer(peer, rxrpc_peer_put_input);
+ return ret;
+}
+
+/*
+ * Deal with a packet that's associated with an extant connection.
+ */
+static int rxrpc_input_packet_on_conn(struct rxrpc_connection *conn,
+ struct sockaddr_rxrpc *peer_srx,
+ struct sk_buff *skb)
+{
+ struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+ struct rxrpc_channel *chan;
+ struct rxrpc_call *call = NULL;
+ unsigned int channel;
+ bool ret;
+
+ if (sp->hdr.securityIndex != conn->security_ix)
+ return rxrpc_direct_abort(skb, rxrpc_eproto_wrong_security,
+ RXKADINCONSISTENCY, -EBADMSG);
+
+ if (sp->hdr.serviceId != conn->service_id) {
+ int old_id;
+
+ if (!test_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags))
+ return rxrpc_protocol_error(skb, rxrpc_eproto_reupgrade);
+
+ old_id = cmpxchg(&conn->service_id, conn->orig_service_id,
+ sp->hdr.serviceId);
+ if (old_id != conn->orig_service_id &&
+ old_id != sp->hdr.serviceId)
+ return rxrpc_protocol_error(skb, rxrpc_eproto_bad_upgrade);
+ }
+
+ if (after(sp->hdr.serial, conn->hi_serial))
+ conn->hi_serial = sp->hdr.serial;
+
+ /* It's a connection-level packet if the call number is 0. */
+ if (sp->hdr.callNumber == 0)
+ return rxrpc_input_conn_packet(conn, skb);
+
+ /* Call-bound packets are routed by connection channel. */
+ channel = sp->hdr.cid & RXRPC_CHANNELMASK;
+ chan = &conn->channels[channel];
+
+ /* Ignore really old calls */
+ if (sp->hdr.callNumber < chan->last_call)
+ return just_discard;
+
+ if (sp->hdr.callNumber == chan->last_call) {
+ if (chan->call ||
+ sp->hdr.type == RXRPC_PACKET_TYPE_ABORT)
+ return just_discard;
+
+ /* For the previous service call, if completed successfully, we
+ * discard all further packets.
+ */
+ if (rxrpc_conn_is_service(conn) &&
+ chan->last_type == RXRPC_PACKET_TYPE_ACK)
+ return just_discard;
+
+ /* But otherwise we need to retransmit the final packet from
+ * data cached in the connection record.
+ */
+ if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA)
+ trace_rxrpc_rx_data(chan->call_debug_id,
+ sp->hdr.seq,
+ sp->hdr.serial,
+ sp->hdr.flags);
+ rxrpc_conn_retransmit_call(conn, skb, channel);
+ return just_discard;
+ }
+
+ call = rxrpc_try_get_call(chan->call, rxrpc_call_get_input);
+
+ if (sp->hdr.callNumber > chan->call_id) {
+ if (rxrpc_to_client(sp)) {
+ rxrpc_put_call(call, rxrpc_call_put_input);
+ return rxrpc_protocol_error(skb,
+ rxrpc_eproto_unexpected_implicit_end);
+ }
+
+ if (call) {
+ rxrpc_implicit_end_call(call, skb);
+ rxrpc_put_call(call, rxrpc_call_put_input);
+ call = NULL;
+ }
+ }
+
+ if (!call) {
+ if (rxrpc_to_client(sp))
+ return rxrpc_protocol_error(skb, rxrpc_eproto_no_client_call);
+ return rxrpc_new_incoming_call(conn->local, conn->peer, conn,
+ peer_srx, skb);
+ }
+
+ ret = rxrpc_input_call_event(call, skb);
+ rxrpc_put_call(call, rxrpc_call_put_input);
+ return ret;
+}
+
+/*
+ * I/O and event handling thread.
+ */
+int rxrpc_io_thread(void *data)
+{
+ struct rxrpc_connection *conn;
+ struct sk_buff_head rx_queue;
+ struct rxrpc_local *local = data;
+ struct rxrpc_call *call;
+ struct sk_buff *skb;
+#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
+ ktime_t now;
+#endif
+ bool should_stop;
+
+ complete(&local->io_thread_ready);
+
+ skb_queue_head_init(&rx_queue);
+
+ set_user_nice(current, MIN_NICE);
+
+ for (;;) {
+ rxrpc_inc_stat(local->rxnet, stat_io_loop);
+
+ /* Deal with connections that want immediate attention. */
+ conn = list_first_entry_or_null(&local->conn_attend_q,
+ struct rxrpc_connection,
+ attend_link);
+ if (conn) {
+ spin_lock_bh(&local->lock);
+ list_del_init(&conn->attend_link);
+ spin_unlock_bh(&local->lock);
+
+ rxrpc_input_conn_event(conn, NULL);
+ rxrpc_put_connection(conn, rxrpc_conn_put_poke);
+ continue;
+ }
+
+ if (test_and_clear_bit(RXRPC_CLIENT_CONN_REAP_TIMER,
+ &local->client_conn_flags))
+ rxrpc_discard_expired_client_conns(local);
+
+ /* Deal with calls that want immediate attention. */
+ if ((call = list_first_entry_or_null(&local->call_attend_q,
+ struct rxrpc_call,
+ attend_link))) {
+ spin_lock_bh(&local->lock);
+ list_del_init(&call->attend_link);
+ spin_unlock_bh(&local->lock);
+
+ trace_rxrpc_call_poked(call);
+ rxrpc_input_call_event(call, NULL);
+ rxrpc_put_call(call, rxrpc_call_put_poke);
+ continue;
+ }
+
+ if (!list_empty(&local->new_client_calls))
+ rxrpc_connect_client_calls(local);
+
+ /* Process received packets and errors. */
+ if ((skb = __skb_dequeue(&rx_queue))) {
+ struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+ switch (skb->mark) {
+ case RXRPC_SKB_MARK_PACKET:
+ skb->priority = 0;
+ if (!rxrpc_input_packet(local, &skb))
+ rxrpc_reject_packet(local, skb);
+ trace_rxrpc_rx_done(skb->mark, skb->priority);
+ rxrpc_free_skb(skb, rxrpc_skb_put_input);
+ break;
+ case RXRPC_SKB_MARK_ERROR:
+ rxrpc_input_error(local, skb);
+ rxrpc_free_skb(skb, rxrpc_skb_put_error_report);
+ break;
+ case RXRPC_SKB_MARK_SERVICE_CONN_SECURED:
+ rxrpc_input_conn_event(sp->conn, skb);
+ rxrpc_put_connection(sp->conn, rxrpc_conn_put_poke);
+ rxrpc_free_skb(skb, rxrpc_skb_put_conn_secured);
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ rxrpc_free_skb(skb, rxrpc_skb_put_unknown);
+ break;
+ }
+ continue;
+ }
+
+ /* Inject a delay into packets if requested. */
+#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
+ now = ktime_get_real();
+ while ((skb = skb_peek(&local->rx_delay_queue))) {
+ if (ktime_before(now, skb->tstamp))
+ break;
+ skb = skb_dequeue(&local->rx_delay_queue);
+ skb_queue_tail(&local->rx_queue, skb);
+ }
+#endif
+
+ if (!skb_queue_empty(&local->rx_queue)) {
+ spin_lock_irq(&local->rx_queue.lock);
+ skb_queue_splice_tail_init(&local->rx_queue, &rx_queue);
+ spin_unlock_irq(&local->rx_queue.lock);
+ continue;
+ }
+
+ set_current_state(TASK_INTERRUPTIBLE);
+ should_stop = kthread_should_stop();
+ if (!skb_queue_empty(&local->rx_queue) ||
+ !list_empty(&local->call_attend_q) ||
+ !list_empty(&local->conn_attend_q) ||
+ !list_empty(&local->new_client_calls) ||
+ test_bit(RXRPC_CLIENT_CONN_REAP_TIMER,
+ &local->client_conn_flags)) {
+ __set_current_state(TASK_RUNNING);
+ continue;
+ }
+
+ if (should_stop)
+ break;
+
+#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
+ skb = skb_peek(&local->rx_delay_queue);
+ if (skb) {
+ unsigned long timeout;
+ ktime_t tstamp = skb->tstamp;
+ ktime_t now = ktime_get_real();
+ s64 delay_ns = ktime_to_ns(ktime_sub(tstamp, now));
+
+ if (delay_ns <= 0) {
+ __set_current_state(TASK_RUNNING);
+ continue;
+ }
+
+ timeout = nsecs_to_jiffies(delay_ns);
+ timeout = max(timeout, 1UL);
+ schedule_timeout(timeout);
+ __set_current_state(TASK_RUNNING);
+ continue;
+ }
+#endif
+
+ schedule();
+ }
+
+ __set_current_state(TASK_RUNNING);
+ rxrpc_see_local(local, rxrpc_local_stop);
+ rxrpc_destroy_local(local);
+ local->io_thread = NULL;
+ rxrpc_see_local(local, rxrpc_local_stopped);
+ return 0;
+}