Merge branch 'VSOCK-sock_diag'

Stefan Hajnoczi says:

====================
VSOCK: add sock_diag interface

v3:
 * Rebased onto net-next/master and resolved Hyper-V transport conflict

v2:
 * Moved tests to tools/testing/vsock/.  I was unable to put them in selftests/
   because they require manual setup of a VMware/KVM guest.
 * Moved to __vsock_in_bound/connected_table() to af_vsock.h
 * Fixed local variable ordering in Patch 4

There is currently no way for userspace to query open AF_VSOCK sockets.  This
means ss(8), netstat(8), and other utilities cannot display AF_VSOCK sockets.

This patch series adds the netlink sock_diag interface for AF_VSOCK.  Userspace
programs sent a DUMP request including an sk_state bitmap to filter sockets
based on their state (connected, listening, etc).  The vsock_diag.ko module
replies with information about matching sockets.  This userspace ABI is defined
in <linux/vm_sockets_diag.h>.

The final patch adds a test suite that exercises the basic cases.

Jorgen and Dexuan: I have only tested the virtio transport but this should also
work for VMCI and Hyper-V.  Please give it a shot if you have time.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

MAINTAINERS

@@ -14286,12 +14286,15 @@ S:	Maintained
 F:	include/linux/virtio_vsock.h
 F:	include/uapi/linux/virtio_vsock.h
 F:	include/uapi/linux/vsockmon.h
+F:	include/uapi/linux/vm_sockets_diag.h
+F:	net/vmw_vsock/diag.c
 F:	net/vmw_vsock/af_vsock_tap.c
 F:	net/vmw_vsock/virtio_transport_common.c
 F:	net/vmw_vsock/virtio_transport.c
 F:	drivers/net/vsockmon.c
 F:	drivers/vhost/vsock.c
 F:	drivers/vhost/vsock.h
+F:	tools/testing/vsock/
 
 VIRTIO CONSOLE DRIVER
 M:	Amit Shah <amit@kernel.org>

include/net/af_vsock.h

@@ -22,11 +22,13 @@
 
 #include "vsock_addr.h"
 
-/* vsock-specific sock->sk_state constants */
-#define VSOCK_SS_LISTEN 255
-
 #define LAST_RESERVED_PORT 1023
 
+#define VSOCK_HASH_SIZE         251
+extern struct list_head vsock_bind_table[VSOCK_HASH_SIZE + 1];
+extern struct list_head vsock_connected_table[VSOCK_HASH_SIZE];
+extern spinlock_t vsock_table_lock;
+
 #define vsock_sk(__sk)    ((struct vsock_sock *)__sk)
 #define sk_vsock(__vsk)   (&(__vsk)->sk)
 
@@ -175,6 +177,18 @@ const struct vsock_transport *vsock_core_get_transport(void);
 
 /**** UTILS ****/
 
+/* vsock_table_lock must be held */
+static inline bool __vsock_in_bound_table(struct vsock_sock *vsk)
+{
+	return !list_empty(&vsk->bound_table);
+}
+
+/* vsock_table_lock must be held */
+static inline bool __vsock_in_connected_table(struct vsock_sock *vsk)
+{
+	return !list_empty(&vsk->connected_table);
+}
+
 void vsock_release_pending(struct sock *pending);
 void vsock_add_pending(struct sock *listener, struct sock *pending);
 void vsock_remove_pending(struct sock *listener, struct sock *pending);

include/uapi/linux/vm_sockets_diag.h

@@ -0,0 +1,33 @@
+/* AF_VSOCK sock_diag(7) interface for querying open sockets */
+
+#ifndef _UAPI__VM_SOCKETS_DIAG_H__
+#define _UAPI__VM_SOCKETS_DIAG_H__
+
+#include <linux/types.h>
+
+/* Request */
+struct vsock_diag_req {
+	__u8	sdiag_family;	/* must be AF_VSOCK */
+	__u8	sdiag_protocol;	/* must be 0 */
+	__u16	pad;		/* must be 0 */
+	__u32	vdiag_states;	/* query bitmap (e.g. 1 << TCP_LISTEN) */
+	__u32	vdiag_ino;	/* must be 0 (reserved) */
+	__u32	vdiag_show;	/* must be 0 (reserved) */
+	__u32	vdiag_cookie[2];
+};
+
+/* Response */
+struct vsock_diag_msg {
+	__u8	vdiag_family;	/* AF_VSOCK */
+	__u8	vdiag_type;	/* SOCK_STREAM or SOCK_DGRAM */
+	__u8	vdiag_state;	/* sk_state (e.g. TCP_LISTEN) */
+	__u8	vdiag_shutdown; /* local RCV_SHUTDOWN | SEND_SHUTDOWN */
+	__u32   vdiag_src_cid;
+	__u32   vdiag_src_port;
+	__u32   vdiag_dst_cid;
+	__u32   vdiag_dst_port;
+	__u32	vdiag_ino;
+	__u32	vdiag_cookie[2];
+};
+
+#endif /* _UAPI__VM_SOCKETS_DIAG_H__ */

net/vmw_vsock/Kconfig

@@ -15,6 +15,16 @@ config VSOCKETS
 	  To compile this driver as a module, choose M here: the module
 	  will be called vsock. If unsure, say N.
 
+config VSOCKETS_DIAG
+	tristate "Virtual Sockets monitoring interface"
+	depends on VSOCKETS
+	default y
+	help
+	  Support for PF_VSOCK sockets monitoring interface used by the ss tool.
+	  If unsure, say Y.
+
+	  Enable this module so userspace applications can query open sockets.
+
 config VMWARE_VMCI_VSOCKETS
 	tristate "VMware VMCI transport for Virtual Sockets"
 	depends on VSOCKETS && VMWARE_VMCI

net/vmw_vsock/Makefile

@@ -1,4 +1,5 @@
 obj-$(CONFIG_VSOCKETS) += vsock.o
+obj-$(CONFIG_VSOCKETS_DIAG) += vsock_diag.o
 obj-$(CONFIG_VMWARE_VMCI_VSOCKETS) += vmw_vsock_vmci_transport.o
 obj-$(CONFIG_VIRTIO_VSOCKETS) += vmw_vsock_virtio_transport.o
 obj-$(CONFIG_VIRTIO_VSOCKETS_COMMON) += vmw_vsock_virtio_transport_common.o
@@ -6,6 +7,8 @@ obj-$(CONFIG_HYPERV_VSOCKETS) += hv_sock.o
 
 vsock-y += af_vsock.o af_vsock_tap.o vsock_addr.o
 
+vsock_diag-y += diag.o
+
 vmw_vsock_vmci_transport-y += vmci_transport.o vmci_transport_notify.o \
 	vmci_transport_notify_qstate.o
 

net/vmw_vsock/af_vsock.c

@@ -36,7 +36,7 @@
  * not support simultaneous connects (two "client" sockets connecting).
  *
  * - "Server" sockets are referred to as listener sockets throughout this
- * implementation because they are in the VSOCK_SS_LISTEN state.  When a
+ * implementation because they are in the TCP_LISTEN state.  When a
  * connection request is received (the second kind of socket mentioned above),
  * we create a new socket and refer to it as a pending socket.  These pending
  * sockets are placed on the pending connection list of the listener socket.
@@ -82,6 +82,15 @@
  * argument, we must ensure the reference count is increased to ensure the
  * socket isn't freed before the function is run; the deferred function will
  * then drop the reference.
+ *
+ * - sk->sk_state uses the TCP state constants because they are widely used by
+ * other address families and exposed to userspace tools like ss(8):
+ *
+ *   TCP_CLOSE - unconnected
+ *   TCP_SYN_SENT - connecting
+ *   TCP_ESTABLISHED - connected
+ *   TCP_CLOSING - disconnecting
+ *   TCP_LISTEN - listening
  */
 
 #include <linux/types.h>
@@ -153,7 +162,6 @@ EXPORT_SYMBOL_GPL(vm_sockets_get_local_cid);
  * vsock_bind_table[VSOCK_HASH_SIZE] is for unbound sockets.  The hash function
  * mods with VSOCK_HASH_SIZE to ensure this.
  */
-#define VSOCK_HASH_SIZE         251
 #define MAX_PORT_RETRIES        24
 
 #define VSOCK_HASH(addr)        ((addr)->svm_port % VSOCK_HASH_SIZE)
@@ -168,9 +176,12 @@ EXPORT_SYMBOL_GPL(vm_sockets_get_local_cid);
 #define vsock_connected_sockets_vsk(vsk)				\
 	vsock_connected_sockets(&(vsk)->remote_addr, &(vsk)->local_addr)
 
-static struct list_head vsock_bind_table[VSOCK_HASH_SIZE + 1];
+struct list_head vsock_bind_table[VSOCK_HASH_SIZE + 1];
-static struct list_head vsock_connected_table[VSOCK_HASH_SIZE];
+EXPORT_SYMBOL_GPL(vsock_bind_table);
-static DEFINE_SPINLOCK(vsock_table_lock);
+struct list_head vsock_connected_table[VSOCK_HASH_SIZE];
+EXPORT_SYMBOL_GPL(vsock_connected_table);
+DEFINE_SPINLOCK(vsock_table_lock);
+EXPORT_SYMBOL_GPL(vsock_table_lock);
 
 /* Autobind this socket to the local address if necessary. */
 static int vsock_auto_bind(struct vsock_sock *vsk)
@@ -248,16 +259,6 @@ static struct sock *__vsock_find_connected_socket(struct sockaddr_vm *src,
 	return NULL;
 }
 
-static bool __vsock_in_bound_table(struct vsock_sock *vsk)
-{
-	return !list_empty(&vsk->bound_table);
-}
-
-static bool __vsock_in_connected_table(struct vsock_sock *vsk)
-{
-	return !list_empty(&vsk->connected_table);
-}
-
 static void vsock_insert_unbound(struct vsock_sock *vsk)
 {
 	spin_lock_bh(&vsock_table_lock);
@@ -485,7 +486,7 @@ void vsock_pending_work(struct work_struct *work)
 	if (vsock_in_connected_table(vsk))
 		vsock_remove_connected(vsk);
 
-	sk->sk_state = SS_FREE;
+	sk->sk_state = TCP_CLOSE;
 
 out:
 	release_sock(sk);
@@ -625,7 +626,6 @@ struct sock *__vsock_create(struct net *net,
 
 	sk->sk_destruct = vsock_sk_destruct;
 	sk->sk_backlog_rcv = vsock_queue_rcv_skb;
-	sk->sk_state = 0;
 	sock_reset_flag(sk, SOCK_DONE);
 
 	INIT_LIST_HEAD(&vsk->bound_table);
@@ -899,7 +899,7 @@ static unsigned int vsock_poll(struct file *file, struct socket *sock,
 		/* Listening sockets that have connections in their accept
 		 * queue can be read.
 		 */
-		if (sk->sk_state == VSOCK_SS_LISTEN
+		if (sk->sk_state == TCP_LISTEN
 		    && !vsock_is_accept_queue_empty(sk))
 			mask |= POLLIN | POLLRDNORM;
 
@@ -928,7 +928,7 @@ static unsigned int vsock_poll(struct file *file, struct socket *sock,
 		}
 
 		/* Connected sockets that can produce data can be written. */
-		if (sk->sk_state == SS_CONNECTED) {
+		if (sk->sk_state == TCP_ESTABLISHED) {
 			if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
 				bool space_avail_now = false;
 				int ret = transport->notify_poll_out(
@@ -950,7 +950,7 @@ static unsigned int vsock_poll(struct file *file, struct socket *sock,
 		 * POLLOUT|POLLWRNORM when peer is closed and nothing to read,
 		 * but local send is not shutdown.
 		 */
-		if (sk->sk_state == SS_UNCONNECTED) {
+		if (sk->sk_state == TCP_CLOSE) {
 			if (!(sk->sk_shutdown & SEND_SHUTDOWN))
 				mask |= POLLOUT | POLLWRNORM;
 
@@ -1120,9 +1120,9 @@ static void vsock_connect_timeout(struct work_struct *work)
 	sk = sk_vsock(vsk);
 
 	lock_sock(sk);
-	if (sk->sk_state == SS_CONNECTING &&
+	if (sk->sk_state == TCP_SYN_SENT &&
 	    (sk->sk_shutdown != SHUTDOWN_MASK)) {
-		sk->sk_state = SS_UNCONNECTED;
+		sk->sk_state = TCP_CLOSE;
 		sk->sk_err = ETIMEDOUT;
 		sk->sk_error_report(sk);
 		cancel = 1;
@@ -1168,7 +1168,7 @@ static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
 		err = -EALREADY;
 		break;
 	default:
-		if ((sk->sk_state == VSOCK_SS_LISTEN) ||
+		if ((sk->sk_state == TCP_LISTEN) ||
 		    vsock_addr_cast(addr, addr_len, &remote_addr) != 0) {
 			err = -EINVAL;
 			goto out;
@@ -1191,7 +1191,7 @@ static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
 		if (err)
 			goto out;
 
-		sk->sk_state = SS_CONNECTING;
+		sk->sk_state = TCP_SYN_SENT;
 
 		err = transport->connect(vsk);
 		if (err < 0)
@@ -1211,7 +1211,7 @@ static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
 	timeout = vsk->connect_timeout;
 	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 
-	while (sk->sk_state != SS_CONNECTED && sk->sk_err == 0) {
+	while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) {
 		if (flags & O_NONBLOCK) {
 			/* If we're not going to block, we schedule a timeout
 			 * function to generate a timeout on the connection
@@ -1234,13 +1234,13 @@ static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
 
 		if (signal_pending(current)) {
 			err = sock_intr_errno(timeout);
-			sk->sk_state = SS_UNCONNECTED;
+			sk->sk_state = TCP_CLOSE;
 			sock->state = SS_UNCONNECTED;
 			vsock_transport_cancel_pkt(vsk);
 			goto out_wait;
 		} else if (timeout == 0) {
 			err = -ETIMEDOUT;
-			sk->sk_state = SS_UNCONNECTED;
+			sk->sk_state = TCP_CLOSE;
 			sock->state = SS_UNCONNECTED;
 			vsock_transport_cancel_pkt(vsk);
 			goto out_wait;
@@ -1251,7 +1251,7 @@ static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
 
 	if (sk->sk_err) {
 		err = -sk->sk_err;
-		sk->sk_state = SS_UNCONNECTED;
+		sk->sk_state = TCP_CLOSE;
 		sock->state = SS_UNCONNECTED;
 	} else {
 		err = 0;
@@ -1284,7 +1284,7 @@ static int vsock_accept(struct socket *sock, struct socket *newsock, int flags,
 		goto out;
 	}
 
-	if (listener->sk_state != VSOCK_SS_LISTEN) {
+	if (listener->sk_state != TCP_LISTEN) {
 		err = -EINVAL;
 		goto out;
 	}
@@ -1374,7 +1374,7 @@ static int vsock_listen(struct socket *sock, int backlog)
 	}
 
 	sk->sk_max_ack_backlog = backlog;
-	sk->sk_state = VSOCK_SS_LISTEN;
+	sk->sk_state = TCP_LISTEN;
 
 	err = 0;
 
@@ -1554,7 +1554,7 @@ static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg,
 
 	/* Callers should not provide a destination with stream sockets. */
 	if (msg->msg_namelen) {
-		err = sk->sk_state == SS_CONNECTED ? -EISCONN : -EOPNOTSUPP;
+		err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP;
 		goto out;
 	}
 
@@ -1565,7 +1565,7 @@ static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg,
 		goto out;
 	}
 
-	if (sk->sk_state != SS_CONNECTED ||
+	if (sk->sk_state != TCP_ESTABLISHED ||
 	    !vsock_addr_bound(&vsk->local_addr)) {
 		err = -ENOTCONN;
 		goto out;
@@ -1689,7 +1689,7 @@ vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 
 	lock_sock(sk);
 
-	if (sk->sk_state != SS_CONNECTED) {
+	if (sk->sk_state != TCP_ESTABLISHED) {
 		/* Recvmsg is supposed to return 0 if a peer performs an
 		 * orderly shutdown. Differentiate between that case and when a
 		 * peer has not connected or a local shutdown occured with the

net/vmw_vsock/diag.c

@@ -0,0 +1,186 @@
+/*
+ * vsock sock_diag(7) module
+ *
+ * Copyright (C) 2017 Red Hat, Inc.
+ * Author: Stefan Hajnoczi <stefanha@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation version 2 and no later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/module.h>
+#include <linux/sock_diag.h>
+#include <linux/vm_sockets_diag.h>
+#include <net/af_vsock.h>
+
+static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
+			u32 portid, u32 seq, u32 flags)
+{
+	struct vsock_sock *vsk = vsock_sk(sk);
+	struct vsock_diag_msg *rep;
+	struct nlmsghdr *nlh;
+
+	nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rep),
+			flags);
+	if (!nlh)
+		return -EMSGSIZE;
+
+	rep = nlmsg_data(nlh);
+	rep->vdiag_family = AF_VSOCK;
+
+	/* Lock order dictates that sk_lock is acquired before
+	 * vsock_table_lock, so we cannot lock here.  Simply don't take
+	 * sk_lock; sk is guaranteed to stay alive since vsock_table_lock is
+	 * held.
+	 */
+	rep->vdiag_type = sk->sk_type;
+	rep->vdiag_state = sk->sk_state;
+	rep->vdiag_shutdown = sk->sk_shutdown;
+	rep->vdiag_src_cid = vsk->local_addr.svm_cid;
+	rep->vdiag_src_port = vsk->local_addr.svm_port;
+	rep->vdiag_dst_cid = vsk->remote_addr.svm_cid;
+	rep->vdiag_dst_port = vsk->remote_addr.svm_port;
+	rep->vdiag_ino = sock_i_ino(sk);
+
+	sock_diag_save_cookie(sk, rep->vdiag_cookie);
+
+	return 0;
+}
+
+static int vsock_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	struct vsock_diag_req *req;
+	struct vsock_sock *vsk;
+	unsigned int bucket;
+	unsigned int last_i;
+	unsigned int table;
+	struct net *net;
+	unsigned int i;
+
+	req = nlmsg_data(cb->nlh);
+	net = sock_net(skb->sk);
+
+	/* State saved between calls: */
+	table = cb->args[0];
+	bucket = cb->args[1];
+	i = last_i = cb->args[2];
+
+	/* TODO VMCI pending sockets? */
+
+	spin_lock_bh(&vsock_table_lock);
+
+	/* Bind table (locally created sockets) */
+	if (table == 0) {
+		while (bucket < ARRAY_SIZE(vsock_bind_table)) {
+			struct list_head *head = &vsock_bind_table[bucket];
+
+			i = 0;
+			list_for_each_entry(vsk, head, bound_table) {
+				struct sock *sk = sk_vsock(vsk);
+
+				if (!net_eq(sock_net(sk), net))
+					continue;
+				if (i < last_i)
+					goto next_bind;
+				if (!(req->vdiag_states & (1 << sk->sk_state)))
+					goto next_bind;
+				if (sk_diag_fill(sk, skb,
+						 NETLINK_CB(cb->skb).portid,
+						 cb->nlh->nlmsg_seq,
+						 NLM_F_MULTI) < 0)
+					goto done;
+next_bind:
+				i++;
+			}
+			last_i = 0;
+			bucket++;
+		}
+
+		table++;
+		bucket = 0;
+	}
+
+	/* Connected table (accepted connections) */
+	while (bucket < ARRAY_SIZE(vsock_connected_table)) {
+		struct list_head *head = &vsock_connected_table[bucket];
+
+		i = 0;
+		list_for_each_entry(vsk, head, connected_table) {
+			struct sock *sk = sk_vsock(vsk);
+
+			/* Skip sockets we've already seen above */
+			if (__vsock_in_bound_table(vsk))
+				continue;
+
+			if (!net_eq(sock_net(sk), net))
+				continue;
+			if (i < last_i)
+				goto next_connected;
+			if (!(req->vdiag_states & (1 << sk->sk_state)))
+				goto next_connected;
+			if (sk_diag_fill(sk, skb,
+					 NETLINK_CB(cb->skb).portid,
+					 cb->nlh->nlmsg_seq,
+					 NLM_F_MULTI) < 0)
+				goto done;
+next_connected:
+			i++;
+		}
+		last_i = 0;
+		bucket++;
+	}
+
+done:
+	spin_unlock_bh(&vsock_table_lock);
+
+	cb->args[0] = table;
+	cb->args[1] = bucket;
+	cb->args[2] = i;
+
+	return skb->len;
+}
+
+static int vsock_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
+{
+	int hdrlen = sizeof(struct vsock_diag_req);
+	struct net *net = sock_net(skb->sk);
+
+	if (nlmsg_len(h) < hdrlen)
+		return -EINVAL;
+
+	if (h->nlmsg_flags & NLM_F_DUMP) {
+		struct netlink_dump_control c = {
+			.dump = vsock_diag_dump,
+		};
+		return netlink_dump_start(net->diag_nlsk, skb, h, &c);
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static const struct sock_diag_handler vsock_diag_handler = {
+	.family = AF_VSOCK,
+	.dump = vsock_diag_handler_dump,
+};
+
+static int __init vsock_diag_init(void)
+{
+	return sock_diag_register(&vsock_diag_handler);
+}
+
+static void __exit vsock_diag_exit(void)
+{
+	sock_diag_unregister(&vsock_diag_handler);
+}
+
+module_init(vsock_diag_init);
+module_exit(vsock_diag_exit);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG,
+			       40 /* AF_VSOCK */);

net/vmw_vsock/hyperv_transport.c

@@ -310,7 +310,7 @@ static void hvs_close_connection(struct vmbus_channel *chan)
 	struct sock *sk = get_per_channel_state(chan);
 	struct vsock_sock *vsk = vsock_sk(sk);
 
-	sk->sk_state = SS_UNCONNECTED;
+	sk->sk_state = TCP_CLOSE;
 	sock_set_flag(sk, SOCK_DONE);
 	vsk->peer_shutdown |= SEND_SHUTDOWN | RCV_SHUTDOWN;
 
@@ -344,8 +344,8 @@ static void hvs_open_connection(struct vmbus_channel *chan)
 	if (!sk)
 		return;
 
-	if ((conn_from_host && sk->sk_state != VSOCK_SS_LISTEN) ||
+	if ((conn_from_host && sk->sk_state != TCP_LISTEN) ||
-	    (!conn_from_host && sk->sk_state != SS_CONNECTING))
+	    (!conn_from_host && sk->sk_state != TCP_SYN_SENT))
 		goto out;
 
 	if (conn_from_host) {
@@ -357,7 +357,7 @@ static void hvs_open_connection(struct vmbus_channel *chan)
 		if (!new)
 			goto out;
 
-		new->sk_state = SS_CONNECTING;
+		new->sk_state = TCP_SYN_SENT;
 		vnew = vsock_sk(new);
 		hvs_new = vnew->trans;
 		hvs_new->chan = chan;
@@ -384,7 +384,7 @@ static void hvs_open_connection(struct vmbus_channel *chan)
 	vmbus_set_chn_rescind_callback(chan, hvs_close_connection);
 
 	if (conn_from_host) {
-		new->sk_state = SS_CONNECTED;
+		new->sk_state = TCP_ESTABLISHED;
 		sk->sk_ack_backlog++;
 
 		hvs_addr_init(&vnew->local_addr, if_type);
@@ -399,7 +399,7 @@ static void hvs_open_connection(struct vmbus_channel *chan)
 		vsock_enqueue_accept(sk, new);
 		release_sock(sk);
 	} else {
-		sk->sk_state = SS_CONNECTED;
+		sk->sk_state = TCP_ESTABLISHED;
 		sk->sk_socket->state = SS_CONNECTED;
 
 		vsock_insert_connected(vsock_sk(sk));

net/vmw_vsock/virtio_transport.c

@@ -414,7 +414,7 @@ static void virtio_vsock_event_fill(struct virtio_vsock *vsock)
 static void virtio_vsock_reset_sock(struct sock *sk)
 {
 	lock_sock(sk);
-	sk->sk_state = SS_UNCONNECTED;
+	sk->sk_state = TCP_CLOSE;
 	sk->sk_err = ECONNRESET;
 	sk->sk_error_report(sk);
 	release_sock(sk);

net/vmw_vsock/virtio_transport_common.c

@@ -708,7 +708,7 @@ static void virtio_transport_do_close(struct vsock_sock *vsk,
 	sock_set_flag(sk, SOCK_DONE);
 	vsk->peer_shutdown = SHUTDOWN_MASK;
 	if (vsock_stream_has_data(vsk) <= 0)
-		sk->sk_state = SS_DISCONNECTING;
+		sk->sk_state = TCP_CLOSING;
 	sk->sk_state_change(sk);
 
 	if (vsk->close_work_scheduled &&
@@ -748,8 +748,8 @@ static bool virtio_transport_close(struct vsock_sock *vsk)
 {
 	struct sock *sk = &vsk->sk;
 
-	if (!(sk->sk_state == SS_CONNECTED ||
+	if (!(sk->sk_state == TCP_ESTABLISHED ||
-	      sk->sk_state == SS_DISCONNECTING))
+	      sk->sk_state == TCP_CLOSING))
 		return true;
 
 	/* Already received SHUTDOWN from peer, reply with RST */
@@ -801,7 +801,7 @@ virtio_transport_recv_connecting(struct sock *sk,
 
 	switch (le16_to_cpu(pkt->hdr.op)) {
 	case VIRTIO_VSOCK_OP_RESPONSE:
-		sk->sk_state = SS_CONNECTED;
+		sk->sk_state = TCP_ESTABLISHED;
 		sk->sk_socket->state = SS_CONNECTED;
 		vsock_insert_connected(vsk);
 		sk->sk_state_change(sk);
@@ -821,7 +821,7 @@ virtio_transport_recv_connecting(struct sock *sk,
 
 destroy:
 	virtio_transport_reset(vsk, pkt);
-	sk->sk_state = SS_UNCONNECTED;
+	sk->sk_state = TCP_CLOSE;
 	sk->sk_err = skerr;
 	sk->sk_error_report(sk);
 	return err;
@@ -857,7 +857,7 @@ virtio_transport_recv_connected(struct sock *sk,
 			vsk->peer_shutdown |= SEND_SHUTDOWN;
 		if (vsk->peer_shutdown == SHUTDOWN_MASK &&
 		    vsock_stream_has_data(vsk) <= 0)
-			sk->sk_state = SS_DISCONNECTING;
+			sk->sk_state = TCP_CLOSING;
 		if (le32_to_cpu(pkt->hdr.flags))
 			sk->sk_state_change(sk);
 		break;
@@ -928,7 +928,7 @@ virtio_transport_recv_listen(struct sock *sk, struct virtio_vsock_pkt *pkt)
 
 	lock_sock_nested(child, SINGLE_DEPTH_NESTING);
 
-	child->sk_state = SS_CONNECTED;
+	child->sk_state = TCP_ESTABLISHED;
 
 	vchild = vsock_sk(child);
 	vsock_addr_init(&vchild->local_addr, le64_to_cpu(pkt->hdr.dst_cid),
@@ -1016,18 +1016,18 @@ void virtio_transport_recv_pkt(struct virtio_vsock_pkt *pkt)
 		sk->sk_write_space(sk);
 
 	switch (sk->sk_state) {
-	case VSOCK_SS_LISTEN:
+	case TCP_LISTEN:
 		virtio_transport_recv_listen(sk, pkt);
 		virtio_transport_free_pkt(pkt);
 		break;
-	case SS_CONNECTING:
+	case TCP_SYN_SENT:
 		virtio_transport_recv_connecting(sk, pkt);
 		virtio_transport_free_pkt(pkt);
 		break;
-	case SS_CONNECTED:
+	case TCP_ESTABLISHED:
 		virtio_transport_recv_connected(sk, pkt);
 		break;
-	case SS_DISCONNECTING:
+	case TCP_CLOSING:
 		virtio_transport_recv_disconnecting(sk, pkt);
 		virtio_transport_free_pkt(pkt);
 		break;

net/vmw_vsock/vmci_transport.c

@@ -742,7 +742,7 @@ static int vmci_transport_recv_stream_cb(void *data, struct vmci_datagram *dg)
 		/* The local context ID may be out of date, update it. */
 		vsk->local_addr.svm_cid = dst.svm_cid;
 
-		if (sk->sk_state == SS_CONNECTED)
+		if (sk->sk_state == TCP_ESTABLISHED)
 			vmci_trans(vsk)->notify_ops->handle_notify_pkt(
 					sk, pkt, true, &dst, &src,
 					&bh_process_pkt);
@@ -800,7 +800,9 @@ static void vmci_transport_handle_detach(struct sock *sk)
 		 * left in our consume queue.
 		 */
 		if (vsock_stream_has_data(vsk) <= 0) {
-			if (sk->sk_state == SS_CONNECTING) {
+			sk->sk_state = TCP_CLOSE;
+
+			if (sk->sk_state == TCP_SYN_SENT) {
 				/* The peer may detach from a queue pair while
 				 * we are still in the connecting state, i.e.,
 				 * if the peer VM is killed after attaching to
@@ -809,12 +811,10 @@ static void vmci_transport_handle_detach(struct sock *sk)
 				 * event like a reset.
 				 */
 
-				sk->sk_state = SS_UNCONNECTED;
 				sk->sk_err = ECONNRESET;
 				sk->sk_error_report(sk);
 				return;
 			}
-			sk->sk_state = SS_UNCONNECTED;
 		}
 		sk->sk_state_change(sk);
 	}
@@ -882,17 +882,17 @@ static void vmci_transport_recv_pkt_work(struct work_struct *work)
 	vsock_sk(sk)->local_addr.svm_cid = pkt->dg.dst.context;
 
 	switch (sk->sk_state) {
-	case VSOCK_SS_LISTEN:
+	case TCP_LISTEN:
 		vmci_transport_recv_listen(sk, pkt);
 		break;
-	case SS_CONNECTING:
+	case TCP_SYN_SENT:
 		/* Processing of pending connections for servers goes through
 		 * the listening socket, so see vmci_transport_recv_listen()
 		 * for that path.
 		 */
 		vmci_transport_recv_connecting_client(sk, pkt);
 		break;
-	case SS_CONNECTED:
+	case TCP_ESTABLISHED:
 		vmci_transport_recv_connected(sk, pkt);
 		break;
 	default:
@@ -941,7 +941,7 @@ static int vmci_transport_recv_listen(struct sock *sk,
 		vsock_sk(pending)->local_addr.svm_cid = pkt->dg.dst.context;
 
 		switch (pending->sk_state) {
-		case SS_CONNECTING:
+		case TCP_SYN_SENT:
 			err = vmci_transport_recv_connecting_server(sk,
 								    pending,
 								    pkt);
@@ -1071,7 +1071,7 @@ static int vmci_transport_recv_listen(struct sock *sk,
 	vsock_add_pending(sk, pending);
 	sk->sk_ack_backlog++;
 
-	pending->sk_state = SS_CONNECTING;
+	pending->sk_state = TCP_SYN_SENT;
 	vmci_trans(vpending)->produce_size =
 		vmci_trans(vpending)->consume_size = qp_size;
 	vmci_trans(vpending)->queue_pair_size = qp_size;
@@ -1196,11 +1196,11 @@ vmci_transport_recv_connecting_server(struct sock *listener,
 	 * the socket will be valid until it is removed from the queue.
 	 *
 	 * If we fail sending the attach below, we remove the socket from the
-	 * connected list and move the socket to SS_UNCONNECTED before
+	 * connected list and move the socket to TCP_CLOSE before
 	 * releasing the lock, so a pending slow path processing of an incoming
 	 * packet will not see the socket in the connected state in that case.
 	 */
-	pending->sk_state = SS_CONNECTED;
+	pending->sk_state = TCP_ESTABLISHED;
 
 	vsock_insert_connected(vpending);
 
@@ -1231,7 +1231,7 @@ vmci_transport_recv_connecting_server(struct sock *listener,
 
 destroy:
 	pending->sk_err = skerr;
-	pending->sk_state = SS_UNCONNECTED;
+	pending->sk_state = TCP_CLOSE;
 	/* As long as we drop our reference, all necessary cleanup will handle
 	 * when the cleanup function drops its reference and our destruct
 	 * implementation is called.  Note that since the listen handler will
@@ -1269,7 +1269,7 @@ vmci_transport_recv_connecting_client(struct sock *sk,
 		 * accounting (it can already be found since it's in the bound
 		 * table).
 		 */
-		sk->sk_state = SS_CONNECTED;
+		sk->sk_state = TCP_ESTABLISHED;
 		sk->sk_socket->state = SS_CONNECTED;
 		vsock_insert_connected(vsk);
 		sk->sk_state_change(sk);
@@ -1337,7 +1337,7 @@ vmci_transport_recv_connecting_client(struct sock *sk,
 destroy:
 	vmci_transport_send_reset(sk, pkt);
 
-	sk->sk_state = SS_UNCONNECTED;
+	sk->sk_state = TCP_CLOSE;
 	sk->sk_err = skerr;
 	sk->sk_error_report(sk);
 	return err;
@@ -1525,7 +1525,7 @@ static int vmci_transport_recv_connected(struct sock *sk,
 		sock_set_flag(sk, SOCK_DONE);
 		vsk->peer_shutdown = SHUTDOWN_MASK;
 		if (vsock_stream_has_data(vsk) <= 0)
-			sk->sk_state = SS_DISCONNECTING;
+			sk->sk_state = TCP_CLOSING;
 
 		sk->sk_state_change(sk);
 		break;
@@ -1789,7 +1789,7 @@ static int vmci_transport_connect(struct vsock_sock *vsk)
 		err = vmci_transport_send_conn_request(
 			sk, vmci_trans(vsk)->queue_pair_size);
 		if (err < 0) {
-			sk->sk_state = SS_UNCONNECTED;
+			sk->sk_state = TCP_CLOSE;
 			return err;
 		}
 	} else {
@@ -1799,7 +1799,7 @@ static int vmci_transport_connect(struct vsock_sock *vsk)
 				sk, vmci_trans(vsk)->queue_pair_size,
 				supported_proto_versions);
 		if (err < 0) {
-			sk->sk_state = SS_UNCONNECTED;
+			sk->sk_state = TCP_CLOSE;
 			return err;
 		}
 

net/vmw_vsock/vmci_transport_notify.c

@@ -355,7 +355,7 @@ vmci_transport_notify_pkt_poll_in(struct sock *sk,
 		 * queue. Ask for notifications when there is something to
 		 * read.
 		 */
-		if (sk->sk_state == SS_CONNECTED) {
+		if (sk->sk_state == TCP_ESTABLISHED) {
 			if (!send_waiting_read(sk, 1))
 				return -1;
 

net/vmw_vsock/vmci_transport_notify_qstate.c

@@ -176,7 +176,7 @@ vmci_transport_notify_pkt_poll_in(struct sock *sk,
 		 * queue. Ask for notifications when there is something to
 		 * read.
 		 */
-		if (sk->sk_state == SS_CONNECTED)
+		if (sk->sk_state == TCP_ESTABLISHED)
 			vsock_block_update_write_window(sk);
 		*data_ready_now = false;
 	}

tools/testing/vsock/.gitignore

@@ -0,0 +1,2 @@
+*.d
+vsock_diag_test

tools/testing/vsock/Makefile

@@ -0,0 +1,9 @@
+all: test
+test: vsock_diag_test
+vsock_diag_test: vsock_diag_test.o timeout.o control.o
+
+CFLAGS += -g -O2 -Werror -Wall -I. -I../../include/uapi -I../../include -Wno-pointer-sign -fno-strict-overflow -fno-strict-aliasing -fno-common -MMD -U_FORTIFY_SOURCE -D_GNU_SOURCE
+.PHONY: all test clean
+clean:
+	${RM} *.o *.d vsock_diag_test
+-include *.d

tools/testing/vsock/README

@@ -0,0 +1,36 @@
+AF_VSOCK test suite
+-------------------
+These tests exercise net/vmw_vsock/ host<->guest sockets for VMware, KVM, and
+Hyper-V.
+
+The following tests are available:
+
+  * vsock_diag_test - vsock_diag.ko module for listing open sockets
+
+The following prerequisite steps are not automated and must be performed prior
+to running tests:
+
+1. Build the kernel and these tests.
+2. Install the kernel and tests on the host.
+3. Install the kernel and tests inside the guest.
+4. Boot the guest and ensure that the AF_VSOCK transport is enabled.
+
+Invoke test binaries in both directions as follows:
+
+  # host=server, guest=client
+  (host)# $TEST_BINARY --mode=server \
+                       --control-port=1234 \
+                       --peer-cid=3
+  (guest)# $TEST_BINARY --mode=client \
+                        --control-host=$HOST_IP \
+                        --control-port=1234 \
+                        --peer-cid=2
+
+  # host=client, guest=server
+  (guest)# $TEST_BINARY --mode=server \
+                        --control-port=1234 \
+                        --peer-cid=2
+  (host)# $TEST_BINARY --mode=client \
+                       --control-port=$GUEST_IP \
+                       --control-port=1234 \
+                       --peer-cid=3

tools/testing/vsock/control.c

@@ -0,0 +1,219 @@
+/* Control socket for client/server test execution
+ *
+ * Copyright (C) 2017 Red Hat, Inc.
+ *
+ * Author: Stefan Hajnoczi <stefanha@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2
+ * of the License.
+ */
+
+/* The client and server may need to coordinate to avoid race conditions like
+ * the client attempting to connect to a socket that the server is not
+ * listening on yet.  The control socket offers a communications channel for
+ * such coordination tasks.
+ *
+ * If the client calls control_expectln("LISTENING"), then it will block until
+ * the server calls control_writeln("LISTENING").  This provides a simple
+ * mechanism for coordinating between the client and the server.
+ */
+
+#include <errno.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#include "timeout.h"
+#include "control.h"
+
+static int control_fd = -1;
+
+/* Open the control socket, either in server or client mode */
+void control_init(const char *control_host,
+		  const char *control_port,
+		  bool server)
+{
+	struct addrinfo hints = {
+		.ai_socktype = SOCK_STREAM,
+	};
+	struct addrinfo *result = NULL;
+	struct addrinfo *ai;
+	int ret;
+
+	ret = getaddrinfo(control_host, control_port, &hints, &result);
+	if (ret != 0) {
+		fprintf(stderr, "%s\n", gai_strerror(ret));
+		exit(EXIT_FAILURE);
+	}
+
+	for (ai = result; ai; ai = ai->ai_next) {
+		int fd;
+		int val = 1;
+
+		fd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
+		if (fd < 0)
+			continue;
+
+		if (!server) {
+			if (connect(fd, ai->ai_addr, ai->ai_addrlen) < 0)
+				goto next;
+			control_fd = fd;
+			printf("Control socket connected to %s:%s.\n",
+			       control_host, control_port);
+			break;
+		}
+
+		if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
+			       &val, sizeof(val)) < 0) {
+			perror("setsockopt");
+			exit(EXIT_FAILURE);
+		}
+
+		if (bind(fd, ai->ai_addr, ai->ai_addrlen) < 0)
+			goto next;
+		if (listen(fd, 1) < 0)
+			goto next;
+
+		printf("Control socket listening on %s:%s\n",
+		       control_host, control_port);
+		fflush(stdout);
+
+		control_fd = accept(fd, NULL, 0);
+		close(fd);
+
+		if (control_fd < 0) {
+			perror("accept");
+			exit(EXIT_FAILURE);
+		}
+		printf("Control socket connection accepted...\n");
+		break;
+
+next:
+		close(fd);
+	}
+
+	if (control_fd < 0) {
+		fprintf(stderr, "Control socket initialization failed.  Invalid address %s:%s?\n",
+			control_host, control_port);
+		exit(EXIT_FAILURE);
+	}
+
+	freeaddrinfo(result);
+}
+
+/* Free resources */
+void control_cleanup(void)
+{
+	close(control_fd);
+	control_fd = -1;
+}
+
+/* Write a line to the control socket */
+void control_writeln(const char *str)
+{
+	ssize_t len = strlen(str);
+	ssize_t ret;
+
+	timeout_begin(TIMEOUT);
+
+	do {
+		ret = send(control_fd, str, len, MSG_MORE);
+		timeout_check("send");
+	} while (ret < 0 && errno == EINTR);
+
+	if (ret != len) {
+		perror("send");
+		exit(EXIT_FAILURE);
+	}
+
+	do {
+		ret = send(control_fd, "\n", 1, 0);
+		timeout_check("send");
+	} while (ret < 0 && errno == EINTR);
+
+	if (ret != 1) {
+		perror("send");
+		exit(EXIT_FAILURE);
+	}
+
+	timeout_end();
+}
+
+/* Return the next line from the control socket (without the trailing newline).
+ *
+ * The program terminates if a timeout occurs.
+ *
+ * The caller must free() the returned string.
+ */
+char *control_readln(void)
+{
+	char *buf = NULL;
+	size_t idx = 0;
+	size_t buflen = 0;
+
+	timeout_begin(TIMEOUT);
+
+	for (;;) {
+		ssize_t ret;
+
+		if (idx >= buflen) {
+			char *new_buf;
+
+			new_buf = realloc(buf, buflen + 80);
+			if (!new_buf) {
+				perror("realloc");
+				exit(EXIT_FAILURE);
+			}
+
+			buf = new_buf;
+			buflen += 80;
+		}
+
+		do {
+			ret = recv(control_fd, &buf[idx], 1, 0);
+			timeout_check("recv");
+		} while (ret < 0 && errno == EINTR);
+
+		if (ret == 0) {
+			fprintf(stderr, "unexpected EOF on control socket\n");
+			exit(EXIT_FAILURE);
+		}
+
+		if (ret != 1) {
+			perror("recv");
+			exit(EXIT_FAILURE);
+		}
+
+		if (buf[idx] == '\n') {
+			buf[idx] = '\0';
+			break;
+		}
+
+		idx++;
+	}
+
+	timeout_end();
+
+	return buf;
+}
+
+/* Wait until a given line is received or a timeout occurs */
+void control_expectln(const char *str)
+{
+	char *line;
+
+	line = control_readln();
+	if (strcmp(str, line) != 0) {
+		fprintf(stderr, "expected \"%s\" on control socket, got \"%s\"\n",
+			str, line);
+		exit(EXIT_FAILURE);
+	}
+
+	free(line);
+}

tools/testing/vsock/control.h

@@ -0,0 +1,13 @@
+#ifndef CONTROL_H
+#define CONTROL_H
+
+#include <stdbool.h>
+
+void control_init(const char *control_host, const char *control_port,
+		  bool server);
+void control_cleanup(void);
+void control_writeln(const char *str);
+char *control_readln(void);
+void control_expectln(const char *str);
+
+#endif /* CONTROL_H */

tools/testing/vsock/timeout.c

@@ -0,0 +1,64 @@
+/* Timeout API for single-threaded programs that use blocking
+ * syscalls (read/write/send/recv/connect/accept).
+ *
+ * Copyright (C) 2017 Red Hat, Inc.
+ *
+ * Author: Stefan Hajnoczi <stefanha@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2
+ * of the License.
+ */
+
+/* Use the following pattern:
+ *
+ *   timeout_begin(TIMEOUT);
+ *   do {
+ *       ret = accept(...);
+ *       timeout_check("accept");
+ *   } while (ret < 0 && ret == EINTR);
+ *   timeout_end();
+ */
+
+#include <stdlib.h>
+#include <stdbool.h>
+#include <unistd.h>
+#include <stdio.h>
+#include "timeout.h"
+
+static volatile bool timeout;
+
+/* SIGALRM handler function.  Do not use sleep(2), alarm(2), or
+ * setitimer(2) while using this API - they may interfere with each
+ * other.
+ */
+void sigalrm(int signo)
+{
+	timeout = true;
+}
+
+/* Start a timeout.  Call timeout_check() to verify that the timeout hasn't
+ * expired.  timeout_end() must be called to stop the timeout.  Timeouts cannot
+ * be nested.
+ */
+void timeout_begin(unsigned int seconds)
+{
+	alarm(seconds);
+}
+
+/* Exit with an error message if the timeout has expired */
+void timeout_check(const char *operation)
+{
+	if (timeout) {
+		fprintf(stderr, "%s timed out\n", operation);
+		exit(EXIT_FAILURE);
+	}
+}
+
+/* Stop a timeout */
+void timeout_end(void)
+{
+	alarm(0);
+	timeout = false;
+}

tools/testing/vsock/timeout.h

@@ -0,0 +1,14 @@
+#ifndef TIMEOUT_H
+#define TIMEOUT_H
+
+enum {
+	/* Default timeout */
+	TIMEOUT = 10 /* seconds */
+};
+
+void sigalrm(int signo);
+void timeout_begin(unsigned int seconds);
+void timeout_check(const char *operation);
+void timeout_end(void);
+
+#endif /* TIMEOUT_H */

tools/testing/vsock/vsock_diag_test.c

@@ -0,0 +1,681 @@
+/*
+ * vsock_diag_test - vsock_diag.ko test suite
+ *
+ * Copyright (C) 2017 Red Hat, Inc.
+ *
+ * Author: Stefan Hajnoczi <stefanha@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2
+ * of the License.
+ */
+
+#include <getopt.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <signal.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <linux/list.h>
+#include <linux/net.h>
+#include <linux/netlink.h>
+#include <linux/sock_diag.h>
+#include <netinet/tcp.h>
+
+#include "../../../include/uapi/linux/vm_sockets.h"
+#include "../../../include/uapi/linux/vm_sockets_diag.h"
+
+#include "timeout.h"
+#include "control.h"
+
+enum test_mode {
+	TEST_MODE_UNSET,
+	TEST_MODE_CLIENT,
+	TEST_MODE_SERVER
+};
+
+/* Per-socket status */
+struct vsock_stat {
+	struct list_head list;
+	struct vsock_diag_msg msg;
+};
+
+static const char *sock_type_str(int type)
+{
+	switch (type) {
+	case SOCK_DGRAM:
+		return "DGRAM";
+	case SOCK_STREAM:
+		return "STREAM";
+	default:
+		return "INVALID TYPE";
+	}
+}
+
+static const char *sock_state_str(int state)
+{
+	switch (state) {
+	case TCP_CLOSE:
+		return "UNCONNECTED";
+	case TCP_SYN_SENT:
+		return "CONNECTING";
+	case TCP_ESTABLISHED:
+		return "CONNECTED";
+	case TCP_CLOSING:
+		return "DISCONNECTING";
+	case TCP_LISTEN:
+		return "LISTEN";
+	default:
+		return "INVALID STATE";
+	}
+}
+
+static const char *sock_shutdown_str(int shutdown)
+{
+	switch (shutdown) {
+	case 1:
+		return "RCV_SHUTDOWN";
+	case 2:
+		return "SEND_SHUTDOWN";
+	case 3:
+		return "RCV_SHUTDOWN | SEND_SHUTDOWN";
+	default:
+		return "0";
+	}
+}
+
+static void print_vsock_addr(FILE *fp, unsigned int cid, unsigned int port)
+{
+	if (cid == VMADDR_CID_ANY)
+		fprintf(fp, "*:");
+	else
+		fprintf(fp, "%u:", cid);
+
+	if (port == VMADDR_PORT_ANY)
+		fprintf(fp, "*");
+	else
+		fprintf(fp, "%u", port);
+}
+
+static void print_vsock_stat(FILE *fp, struct vsock_stat *st)
+{
+	print_vsock_addr(fp, st->msg.vdiag_src_cid, st->msg.vdiag_src_port);
+	fprintf(fp, " ");
+	print_vsock_addr(fp, st->msg.vdiag_dst_cid, st->msg.vdiag_dst_port);
+	fprintf(fp, " %s %s %s %u\n",
+		sock_type_str(st->msg.vdiag_type),
+		sock_state_str(st->msg.vdiag_state),
+		sock_shutdown_str(st->msg.vdiag_shutdown),
+		st->msg.vdiag_ino);
+}
+
+static void print_vsock_stats(FILE *fp, struct list_head *head)
+{
+	struct vsock_stat *st;
+
+	list_for_each_entry(st, head, list)
+		print_vsock_stat(fp, st);
+}
+
+static struct vsock_stat *find_vsock_stat(struct list_head *head, int fd)
+{
+	struct vsock_stat *st;
+	struct stat stat;
+
+	if (fstat(fd, &stat) < 0) {
+		perror("fstat");
+		exit(EXIT_FAILURE);
+	}
+
+	list_for_each_entry(st, head, list)
+		if (st->msg.vdiag_ino == stat.st_ino)
+			return st;
+
+	fprintf(stderr, "cannot find fd %d\n", fd);
+	exit(EXIT_FAILURE);
+}
+
+static void check_no_sockets(struct list_head *head)
+{
+	if (!list_empty(head)) {
+		fprintf(stderr, "expected no sockets\n");
+		print_vsock_stats(stderr, head);
+		exit(1);
+	}
+}
+
+static void check_num_sockets(struct list_head *head, int expected)
+{
+	struct list_head *node;
+	int n = 0;
+
+	list_for_each(node, head)
+		n++;
+
+	if (n != expected) {
+		fprintf(stderr, "expected %d sockets, found %d\n",
+			expected, n);
+		print_vsock_stats(stderr, head);
+		exit(EXIT_FAILURE);
+	}
+}
+
+static void check_socket_state(struct vsock_stat *st, __u8 state)
+{
+	if (st->msg.vdiag_state != state) {
+		fprintf(stderr, "expected socket state %#x, got %#x\n",
+			state, st->msg.vdiag_state);
+		exit(EXIT_FAILURE);
+	}
+}
+
+static void send_req(int fd)
+{
+	struct sockaddr_nl nladdr = {
+		.nl_family = AF_NETLINK,
+	};
+	struct {
+		struct nlmsghdr nlh;
+		struct vsock_diag_req vreq;
+	} req = {
+		.nlh = {
+			.nlmsg_len = sizeof(req),
+			.nlmsg_type = SOCK_DIAG_BY_FAMILY,
+			.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP,
+		},
+		.vreq = {
+			.sdiag_family = AF_VSOCK,
+			.vdiag_states = ~(__u32)0,
+		},
+	};
+	struct iovec iov = {
+		.iov_base = &req,
+		.iov_len = sizeof(req),
+	};
+	struct msghdr msg = {
+		.msg_name = &nladdr,
+		.msg_namelen = sizeof(nladdr),
+		.msg_iov = &iov,
+		.msg_iovlen = 1,
+	};
+
+	for (;;) {
+		if (sendmsg(fd, &msg, 0) < 0) {
+			if (errno == EINTR)
+				continue;
+
+			perror("sendmsg");
+			exit(EXIT_FAILURE);
+		}
+
+		return;
+	}
+}
+
+static ssize_t recv_resp(int fd, void *buf, size_t len)
+{
+	struct sockaddr_nl nladdr = {
+		.nl_family = AF_NETLINK,
+	};
+	struct iovec iov = {
+		.iov_base = buf,
+		.iov_len = len,
+	};
+	struct msghdr msg = {
+		.msg_name = &nladdr,
+		.msg_namelen = sizeof(nladdr),
+		.msg_iov = &iov,
+		.msg_iovlen = 1,
+	};
+	ssize_t ret;
+
+	do {
+		ret = recvmsg(fd, &msg, 0);
+	} while (ret < 0 && errno == EINTR);
+
+	if (ret < 0) {
+		perror("recvmsg");
+		exit(EXIT_FAILURE);
+	}
+
+	return ret;
+}
+
+static void add_vsock_stat(struct list_head *sockets,
+			   const struct vsock_diag_msg *resp)
+{
+	struct vsock_stat *st;
+
+	st = malloc(sizeof(*st));
+	if (!st) {
+		perror("malloc");
+		exit(EXIT_FAILURE);
+	}
+
+	st->msg = *resp;
+	list_add_tail(&st->list, sockets);
+}
+
+/*
+ * Read vsock stats into a list.
+ */
+static void read_vsock_stat(struct list_head *sockets)
+{
+	long buf[8192 / sizeof(long)];
+	int fd;
+
+	fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_SOCK_DIAG);
+	if (fd < 0) {
+		perror("socket");
+		exit(EXIT_FAILURE);
+	}
+
+	send_req(fd);
+
+	for (;;) {
+		const struct nlmsghdr *h;
+		ssize_t ret;
+
+		ret = recv_resp(fd, buf, sizeof(buf));
+		if (ret == 0)
+			goto done;
+		if (ret < sizeof(*h)) {
+			fprintf(stderr, "short read of %zd bytes\n", ret);
+			exit(EXIT_FAILURE);
+		}
+
+		h = (struct nlmsghdr *)buf;
+
+		while (NLMSG_OK(h, ret)) {
+			if (h->nlmsg_type == NLMSG_DONE)
+				goto done;
+
+			if (h->nlmsg_type == NLMSG_ERROR) {
+				const struct nlmsgerr *err = NLMSG_DATA(h);
+
+				if (h->nlmsg_len < NLMSG_LENGTH(sizeof(*err)))
+					fprintf(stderr, "NLMSG_ERROR\n");
+				else {
+					errno = -err->error;
+					perror("NLMSG_ERROR");
+				}
+
+				exit(EXIT_FAILURE);
+			}
+
+			if (h->nlmsg_type != SOCK_DIAG_BY_FAMILY) {
+				fprintf(stderr, "unexpected nlmsg_type %#x\n",
+					h->nlmsg_type);
+				exit(EXIT_FAILURE);
+			}
+			if (h->nlmsg_len <
+			    NLMSG_LENGTH(sizeof(struct vsock_diag_msg))) {
+				fprintf(stderr, "short vsock_diag_msg\n");
+				exit(EXIT_FAILURE);
+			}
+
+			add_vsock_stat(sockets, NLMSG_DATA(h));
+
+			h = NLMSG_NEXT(h, ret);
+		}
+	}
+
+done:
+	close(fd);
+}
+
+static void free_sock_stat(struct list_head *sockets)
+{
+	struct vsock_stat *st;
+	struct vsock_stat *next;
+
+	list_for_each_entry_safe(st, next, sockets, list)
+		free(st);
+}
+
+static void test_no_sockets(unsigned int peer_cid)
+{
+	LIST_HEAD(sockets);
+
+	read_vsock_stat(&sockets);
+
+	check_no_sockets(&sockets);
+
+	free_sock_stat(&sockets);
+}
+
+static void test_listen_socket_server(unsigned int peer_cid)
+{
+	union {
+		struct sockaddr sa;
+		struct sockaddr_vm svm;
+	} addr = {
+		.svm = {
+			.svm_family = AF_VSOCK,
+			.svm_port = 1234,
+			.svm_cid = VMADDR_CID_ANY,
+		},
+	};
+	LIST_HEAD(sockets);
+	struct vsock_stat *st;
+	int fd;
+
+	fd = socket(AF_VSOCK, SOCK_STREAM, 0);
+
+	if (bind(fd, &addr.sa, sizeof(addr.svm)) < 0) {
+		perror("bind");
+		exit(EXIT_FAILURE);
+	}
+
+	if (listen(fd, 1) < 0) {
+		perror("listen");
+		exit(EXIT_FAILURE);
+	}
+
+	read_vsock_stat(&sockets);
+
+	check_num_sockets(&sockets, 1);
+	st = find_vsock_stat(&sockets, fd);
+	check_socket_state(st, TCP_LISTEN);
+
+	close(fd);
+	free_sock_stat(&sockets);
+}
+
+static void test_connect_client(unsigned int peer_cid)
+{
+	union {
+		struct sockaddr sa;
+		struct sockaddr_vm svm;
+	} addr = {
+		.svm = {
+			.svm_family = AF_VSOCK,
+			.svm_port = 1234,
+			.svm_cid = peer_cid,
+		},
+	};
+	int fd;
+	int ret;
+	LIST_HEAD(sockets);
+	struct vsock_stat *st;
+
+	control_expectln("LISTENING");
+
+	fd = socket(AF_VSOCK, SOCK_STREAM, 0);
+
+	timeout_begin(TIMEOUT);
+	do {
+		ret = connect(fd, &addr.sa, sizeof(addr.svm));
+		timeout_check("connect");
+	} while (ret < 0 && errno == EINTR);
+	timeout_end();
+
+	if (ret < 0) {
+		perror("connect");
+		exit(EXIT_FAILURE);
+	}
+
+	read_vsock_stat(&sockets);
+
+	check_num_sockets(&sockets, 1);
+	st = find_vsock_stat(&sockets, fd);
+	check_socket_state(st, TCP_ESTABLISHED);
+
+	control_expectln("DONE");
+	control_writeln("DONE");
+
+	close(fd);
+	free_sock_stat(&sockets);
+}
+
+static void test_connect_server(unsigned int peer_cid)
+{
+	union {
+		struct sockaddr sa;
+		struct sockaddr_vm svm;
+	} addr = {
+		.svm = {
+			.svm_family = AF_VSOCK,
+			.svm_port = 1234,
+			.svm_cid = VMADDR_CID_ANY,
+		},
+	};
+	union {
+		struct sockaddr sa;
+		struct sockaddr_vm svm;
+	} clientaddr;
+	socklen_t clientaddr_len = sizeof(clientaddr.svm);
+	LIST_HEAD(sockets);
+	struct vsock_stat *st;
+	int fd;
+	int client_fd;
+
+	fd = socket(AF_VSOCK, SOCK_STREAM, 0);
+
+	if (bind(fd, &addr.sa, sizeof(addr.svm)) < 0) {
+		perror("bind");
+		exit(EXIT_FAILURE);
+	}
+
+	if (listen(fd, 1) < 0) {
+		perror("listen");
+		exit(EXIT_FAILURE);
+	}
+
+	control_writeln("LISTENING");
+
+	timeout_begin(TIMEOUT);
+	do {
+		client_fd = accept(fd, &clientaddr.sa, &clientaddr_len);
+		timeout_check("accept");
+	} while (client_fd < 0 && errno == EINTR);
+	timeout_end();
+
+	if (client_fd < 0) {
+		perror("accept");
+		exit(EXIT_FAILURE);
+	}
+	if (clientaddr.sa.sa_family != AF_VSOCK) {
+		fprintf(stderr, "expected AF_VSOCK from accept(2), got %d\n",
+			clientaddr.sa.sa_family);
+		exit(EXIT_FAILURE);
+	}
+	if (clientaddr.svm.svm_cid != peer_cid) {
+		fprintf(stderr, "expected peer CID %u from accept(2), got %u\n",
+			peer_cid, clientaddr.svm.svm_cid);
+		exit(EXIT_FAILURE);
+	}
+
+	read_vsock_stat(&sockets);
+
+	check_num_sockets(&sockets, 2);
+	find_vsock_stat(&sockets, fd);
+	st = find_vsock_stat(&sockets, client_fd);
+	check_socket_state(st, TCP_ESTABLISHED);
+
+	control_writeln("DONE");
+	control_expectln("DONE");
+
+	close(client_fd);
+	close(fd);
+	free_sock_stat(&sockets);
+}
+
+static struct {
+	const char *name;
+	void (*run_client)(unsigned int peer_cid);
+	void (*run_server)(unsigned int peer_cid);
+} test_cases[] = {
+	{
+		.name = "No sockets",
+		.run_server = test_no_sockets,
+	},
+	{
+		.name = "Listen socket",
+		.run_server = test_listen_socket_server,
+	},
+	{
+		.name = "Connect",
+		.run_client = test_connect_client,
+		.run_server = test_connect_server,
+	},
+	{},
+};
+
+static void init_signals(void)
+{
+	struct sigaction act = {
+		.sa_handler = sigalrm,
+	};
+
+	sigaction(SIGALRM, &act, NULL);
+	signal(SIGPIPE, SIG_IGN);
+}
+
+static unsigned int parse_cid(const char *str)
+{
+	char *endptr = NULL;
+	unsigned long int n;
+
+	errno = 0;
+	n = strtoul(str, &endptr, 10);
+	if (errno || *endptr != '\0') {
+		fprintf(stderr, "malformed CID \"%s\"\n", str);
+		exit(EXIT_FAILURE);
+	}
+	return n;
+}
+
+static const char optstring[] = "";
+static const struct option longopts[] = {
+	{
+		.name = "control-host",
+		.has_arg = required_argument,
+		.val = 'H',
+	},
+	{
+		.name = "control-port",
+		.has_arg = required_argument,
+		.val = 'P',
+	},
+	{
+		.name = "mode",
+		.has_arg = required_argument,
+		.val = 'm',
+	},
+	{
+		.name = "peer-cid",
+		.has_arg = required_argument,
+		.val = 'p',
+	},
+	{
+		.name = "help",
+		.has_arg = no_argument,
+		.val = '?',
+	},
+	{},
+};
+
+static void usage(void)
+{
+	fprintf(stderr, "Usage: vsock_diag_test [--help] [--control-host=<host>] --control-port=<port> --mode=client|server --peer-cid=<cid>\n"
+		"\n"
+		"  Server: vsock_diag_test --control-port=1234 --mode=server --peer-cid=3\n"
+		"  Client: vsock_diag_test --control-host=192.168.0.1 --control-port=1234 --mode=client --peer-cid=2\n"
+		"\n"
+		"Run vsock_diag.ko tests.  Must be launched in both\n"
+		"guest and host.  One side must use --mode=client and\n"
+		"the other side must use --mode=server.\n"
+		"\n"
+		"A TCP control socket connection is used to coordinate tests\n"
+		"between the client and the server.  The server requires a\n"
+		"listen address and the client requires an address to\n"
+		"connect to.\n"
+		"\n"
+		"The CID of the other side must be given with --peer-cid=<cid>.\n");
+	exit(EXIT_FAILURE);
+}
+
+int main(int argc, char **argv)
+{
+	const char *control_host = NULL;
+	const char *control_port = NULL;
+	int mode = TEST_MODE_UNSET;
+	unsigned int peer_cid = VMADDR_CID_ANY;
+	int i;
+
+	init_signals();
+
+	for (;;) {
+		int opt = getopt_long(argc, argv, optstring, longopts, NULL);
+
+		if (opt == -1)
+			break;
+
+		switch (opt) {
+		case 'H':
+			control_host = optarg;
+			break;
+		case 'm':
+			if (strcmp(optarg, "client") == 0)
+				mode = TEST_MODE_CLIENT;
+			else if (strcmp(optarg, "server") == 0)
+				mode = TEST_MODE_SERVER;
+			else {
+				fprintf(stderr, "--mode must be \"client\" or \"server\"\n");
+				return EXIT_FAILURE;
+			}
+			break;
+		case 'p':
+			peer_cid = parse_cid(optarg);
+			break;
+		case 'P':
+			control_port = optarg;
+			break;
+		case '?':
+		default:
+			usage();
+		}
+	}
+
+	if (!control_port)
+		usage();
+	if (mode == TEST_MODE_UNSET)
+		usage();
+	if (peer_cid == VMADDR_CID_ANY)
+		usage();
+
+	if (!control_host) {
+		if (mode != TEST_MODE_SERVER)
+			usage();
+		control_host = "0.0.0.0";
+	}
+
+	control_init(control_host, control_port, mode == TEST_MODE_SERVER);
+
+	for (i = 0; test_cases[i].name; i++) {
+		void (*run)(unsigned int peer_cid);
+
+		printf("%s...", test_cases[i].name);
+		fflush(stdout);
+
+		if (mode == TEST_MODE_CLIENT)
+			run = test_cases[i].run_client;
+		else
+			run = test_cases[i].run_server;
+
+		if (run)
+			run(peer_cid);
+
+		printf("ok\n");
+	}
+
+	control_cleanup();
+	return EXIT_SUCCESS;
+}