Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 778 insertions, 0 deletions

diff --git a/net/phonet/socket.c b/net/phonet/socket.c
new file mode 100644
index 000000000..631a99cdb
--- /dev/null
+++ b/net/phonet/socket.c
@@ -0,0 +1,778 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * File: socket.c
+ *
+ * Phonet sockets
+ *
+ * Copyright (C) 2008 Nokia Corporation.
+ *
+ * Authors: Sakari Ailus <sakari.ailus@nokia.com>
+ *          Rémi Denis-Courmont
+ */
+
+#include <linux/gfp.h>
+#include <linux/kernel.h>
+#include <linux/net.h>
+#include <linux/poll.h>
+#include <linux/sched/signal.h>
+
+#include <net/sock.h>
+#include <net/tcp_states.h>
+
+#include <linux/phonet.h>
+#include <linux/export.h>
+#include <net/phonet/phonet.h>
+#include <net/phonet/pep.h>
+#include <net/phonet/pn_dev.h>
+
+static int pn_socket_release(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+
+	if (sk) {
+		sock->sk = NULL;
+		sk->sk_prot->close(sk, 0);
+	}
+	return 0;
+}
+
+#define PN_HASHSIZE	16
+#define PN_HASHMASK	(PN_HASHSIZE-1)
+
+
+static struct  {
+	struct hlist_head hlist[PN_HASHSIZE];
+	struct mutex lock;
+} pnsocks;
+
+void __init pn_sock_init(void)
+{
+	unsigned int i;
+
+	for (i = 0; i < PN_HASHSIZE; i++)
+		INIT_HLIST_HEAD(pnsocks.hlist + i);
+	mutex_init(&pnsocks.lock);
+}
+
+static struct hlist_head *pn_hash_list(u16 obj)
+{
+	return pnsocks.hlist + (obj & PN_HASHMASK);
+}
+
+/*
+ * Find address based on socket address, match only certain fields.
+ * Also grab sock if it was found. Remember to sock_put it later.
+ */
+struct sock *pn_find_sock_by_sa(struct net *net, const struct sockaddr_pn *spn)
+{
+	struct sock *sknode;
+	struct sock *rval = NULL;
+	u16 obj = pn_sockaddr_get_object(spn);
+	u8 res = spn->spn_resource;
+	struct hlist_head *hlist = pn_hash_list(obj);
+
+	rcu_read_lock();
+	sk_for_each_rcu(sknode, hlist) {
+		struct pn_sock *pn = pn_sk(sknode);
+		BUG_ON(!pn->sobject); /* unbound socket */
+
+		if (!net_eq(sock_net(sknode), net))
+			continue;
+		if (pn_port(obj)) {
+			/* Look up socket by port */
+			if (pn_port(pn->sobject) != pn_port(obj))
+				continue;
+		} else {
+			/* If port is zero, look up by resource */
+			if (pn->resource != res)
+				continue;
+		}
+		if (pn_addr(pn->sobject) &&
+		    pn_addr(pn->sobject) != pn_addr(obj))
+			continue;
+
+		rval = sknode;
+		sock_hold(sknode);
+		break;
+	}
+	rcu_read_unlock();
+
+	return rval;
+}
+
+/* Deliver a broadcast packet (only in bottom-half) */
+void pn_deliver_sock_broadcast(struct net *net, struct sk_buff *skb)
+{
+	struct hlist_head *hlist = pnsocks.hlist;
+	unsigned int h;
+
+	rcu_read_lock();
+	for (h = 0; h < PN_HASHSIZE; h++) {
+		struct sock *sknode;
+
+		sk_for_each(sknode, hlist) {
+			struct sk_buff *clone;
+
+			if (!net_eq(sock_net(sknode), net))
+				continue;
+			if (!sock_flag(sknode, SOCK_BROADCAST))
+				continue;
+
+			clone = skb_clone(skb, GFP_ATOMIC);
+			if (clone) {
+				sock_hold(sknode);
+				sk_receive_skb(sknode, clone, 0);
+			}
+		}
+		hlist++;
+	}
+	rcu_read_unlock();
+}
+
+int pn_sock_hash(struct sock *sk)
+{
+	struct hlist_head *hlist = pn_hash_list(pn_sk(sk)->sobject);
+
+	mutex_lock(&pnsocks.lock);
+	sk_add_node_rcu(sk, hlist);
+	mutex_unlock(&pnsocks.lock);
+
+	return 0;
+}
+EXPORT_SYMBOL(pn_sock_hash);
+
+void pn_sock_unhash(struct sock *sk)
+{
+	mutex_lock(&pnsocks.lock);
+	sk_del_node_init_rcu(sk);
+	mutex_unlock(&pnsocks.lock);
+	pn_sock_unbind_all_res(sk);
+	synchronize_rcu();
+}
+EXPORT_SYMBOL(pn_sock_unhash);
+
+static DEFINE_MUTEX(port_mutex);
+
+static int pn_socket_bind(struct socket *sock, struct sockaddr_unsized *addr, int len)
+{
+	struct sock *sk = sock->sk;
+	struct pn_sock *pn = pn_sk(sk);
+	struct sockaddr_pn *spn = (struct sockaddr_pn *)addr;
+	int err;
+	u16 handle;
+	u8 saddr;
+
+	if (sk->sk_prot->bind)
+		return sk->sk_prot->bind(sk, addr, len);
+
+	if (len < sizeof(struct sockaddr_pn))
+		return -EINVAL;
+	if (spn->spn_family != AF_PHONET)
+		return -EAFNOSUPPORT;
+
+	handle = pn_sockaddr_get_object((struct sockaddr_pn *)addr);
+	saddr = pn_addr(handle);
+	if (saddr && phonet_address_lookup(sock_net(sk), saddr))
+		return -EADDRNOTAVAIL;
+
+	lock_sock(sk);
+	if (sk->sk_state != TCP_CLOSE || pn_port(pn->sobject)) {
+		err = -EINVAL; /* attempt to rebind */
+		goto out;
+	}
+	WARN_ON(sk_hashed(sk));
+	mutex_lock(&port_mutex);
+	err = sk->sk_prot->get_port(sk, pn_port(handle));
+	if (err)
+		goto out_port;
+
+	/* get_port() sets the port, bind() sets the address if applicable */
+	pn->sobject = pn_object(saddr, pn_port(pn->sobject));
+	pn->resource = spn->spn_resource;
+
+	/* Enable RX on the socket */
+	err = sk->sk_prot->hash(sk);
+out_port:
+	mutex_unlock(&port_mutex);
+out:
+	release_sock(sk);
+	return err;
+}
+
+static int pn_socket_autobind(struct socket *sock)
+{
+	struct sockaddr_pn sa;
+	int err;
+
+	memset(&sa, 0, sizeof(sa));
+	sa.spn_family = AF_PHONET;
+	err = pn_socket_bind(sock, (struct sockaddr_unsized *)&sa,
+			     sizeof(struct sockaddr_pn));
+	/*
+	 * pn_socket_bind() also returns -EINVAL when sk_state != TCP_CLOSE
+	 * without a prior bind, so -EINVAL alone is not sufficient to infer
+	 * that the socket was already bound.  Only treat it as "already
+	 * bound" when the port is non-zero; otherwise propagate the error
+	 * instead of crashing the kernel.
+	 */
+	if (err != -EINVAL || unlikely(!pn_port(pn_sk(sock->sk)->sobject)))
+		return err;
+	return 0; /* socket was already bound */
+}
+
+static int pn_socket_connect(struct socket *sock, struct sockaddr_unsized *addr,
+			     int len, int flags)
+{
+	struct sock *sk = sock->sk;
+	struct pn_sock *pn = pn_sk(sk);
+	struct sockaddr_pn *spn = (struct sockaddr_pn *)addr;
+	struct task_struct *tsk = current;
+	long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
+	int err;
+
+	if (pn_socket_autobind(sock))
+		return -ENOBUFS;
+	if (len < sizeof(struct sockaddr_pn))
+		return -EINVAL;
+	if (spn->spn_family != AF_PHONET)
+		return -EAFNOSUPPORT;
+
+	lock_sock(sk);
+
+	switch (sock->state) {
+	case SS_UNCONNECTED:
+		if (sk->sk_state != TCP_CLOSE) {
+			err = -EISCONN;
+			goto out;
+		}
+		break;
+	case SS_CONNECTING:
+		err = -EALREADY;
+		goto out;
+	default:
+		err = -EISCONN;
+		goto out;
+	}
+
+	pn->dobject = pn_sockaddr_get_object(spn);
+	pn->resource = pn_sockaddr_get_resource(spn);
+	sock->state = SS_CONNECTING;
+
+	err = sk->sk_prot->connect(sk, addr, len);
+	if (err) {
+		sock->state = SS_UNCONNECTED;
+		pn->dobject = 0;
+		goto out;
+	}
+
+	while (sk->sk_state == TCP_SYN_SENT) {
+		DEFINE_WAIT(wait);
+
+		if (!timeo) {
+			err = -EINPROGRESS;
+			goto out;
+		}
+		if (signal_pending(tsk)) {
+			err = sock_intr_errno(timeo);
+			goto out;
+		}
+
+		prepare_to_wait_exclusive(sk_sleep(sk), &wait,
+						TASK_INTERRUPTIBLE);
+		release_sock(sk);
+		timeo = schedule_timeout(timeo);
+		lock_sock(sk);
+		finish_wait(sk_sleep(sk), &wait);
+	}
+
+	if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED))
+		err = 0;
+	else if (sk->sk_state == TCP_CLOSE_WAIT)
+		err = -ECONNRESET;
+	else
+		err = -ECONNREFUSED;
+	sock->state = err ? SS_UNCONNECTED : SS_CONNECTED;
+out:
+	release_sock(sk);
+	return err;
+}
+
+static int pn_socket_accept(struct socket *sock, struct socket *newsock,
+			    struct proto_accept_arg *arg)
+{
+	struct sock *sk = sock->sk;
+	struct sock *newsk;
+
+	if (unlikely(sk->sk_state != TCP_LISTEN))
+		return -EINVAL;
+
+	newsk = sk->sk_prot->accept(sk, arg);
+	if (!newsk)
+		return arg->err;
+
+	lock_sock(newsk);
+	sock_graft(newsk, newsock);
+	newsock->state = SS_CONNECTED;
+	release_sock(newsk);
+	return 0;
+}
+
+static int pn_socket_getname(struct socket *sock, struct sockaddr *addr,
+				int peer)
+{
+	struct sock *sk = sock->sk;
+	struct pn_sock *pn = pn_sk(sk);
+
+	memset(addr, 0, sizeof(struct sockaddr_pn));
+	addr->sa_family = AF_PHONET;
+	if (!peer) /* Race with bind() here is userland's problem. */
+		pn_sockaddr_set_object((struct sockaddr_pn *)addr,
+					pn->sobject);
+
+	return sizeof(struct sockaddr_pn);
+}
+
+static __poll_t pn_socket_poll(struct file *file, struct socket *sock,
+					poll_table *wait)
+{
+	struct sock *sk = sock->sk;
+	struct pep_sock *pn = pep_sk(sk);
+	__poll_t mask = 0;
+
+	poll_wait(file, sk_sleep(sk), wait);
+
+	if (sk->sk_state == TCP_CLOSE)
+		return EPOLLERR;
+	if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
+		mask |= EPOLLIN | EPOLLRDNORM;
+	if (!skb_queue_empty_lockless(&pn->ctrlreq_queue))
+		mask |= EPOLLPRI;
+	if (!mask && sk->sk_state == TCP_CLOSE_WAIT)
+		return EPOLLHUP;
+
+	if (sk->sk_state == TCP_ESTABLISHED &&
+		refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf &&
+		atomic_read(&pn->tx_credits))
+		mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
+
+	return mask;
+}
+
+static int pn_socket_ioctl(struct socket *sock, unsigned int cmd,
+				unsigned long arg)
+{
+	struct sock *sk = sock->sk;
+	struct pn_sock *pn = pn_sk(sk);
+
+	if (cmd == SIOCPNGETOBJECT) {
+		struct net_device *dev;
+		u16 handle;
+		u8 saddr;
+
+		if (get_user(handle, (__u16 __user *)arg))
+			return -EFAULT;
+
+		lock_sock(sk);
+		if (sk->sk_bound_dev_if)
+			dev = dev_get_by_index(sock_net(sk),
+						sk->sk_bound_dev_if);
+		else
+			dev = phonet_device_get(sock_net(sk));
+		if (dev && (dev->flags & IFF_UP))
+			saddr = phonet_address_get(dev, pn_addr(handle));
+		else
+			saddr = PN_NO_ADDR;
+		release_sock(sk);
+
+		dev_put(dev);
+		if (saddr == PN_NO_ADDR)
+			return -EHOSTUNREACH;
+
+		handle = pn_object(saddr, pn_port(pn->sobject));
+		return put_user(handle, (__u16 __user *)arg);
+	}
+
+	return sk_ioctl(sk, cmd, (void __user *)arg);
+}
+
+static int pn_socket_listen(struct socket *sock, int backlog)
+{
+	struct sock *sk = sock->sk;
+	int err = 0;
+
+	if (pn_socket_autobind(sock))
+		return -ENOBUFS;
+
+	lock_sock(sk);
+	if (sock->state != SS_UNCONNECTED) {
+		err = -EINVAL;
+		goto out;
+	}
+
+	if (sk->sk_state != TCP_LISTEN) {
+		sk->sk_state = TCP_LISTEN;
+		sk->sk_ack_backlog = 0;
+	}
+	sk->sk_max_ack_backlog = backlog;
+out:
+	release_sock(sk);
+	return err;
+}
+
+static int pn_socket_sendmsg(struct socket *sock, struct msghdr *m,
+			     size_t total_len)
+{
+	struct sock *sk = sock->sk;
+
+	if (pn_socket_autobind(sock))
+		return -EAGAIN;
+
+	return sk->sk_prot->sendmsg(sk, m, total_len);
+}
+
+const struct proto_ops phonet_dgram_ops = {
+	.family		= AF_PHONET,
+	.owner		= THIS_MODULE,
+	.release	= pn_socket_release,
+	.bind		= pn_socket_bind,
+	.connect	= sock_no_connect,
+	.socketpair	= sock_no_socketpair,
+	.accept		= sock_no_accept,
+	.getname	= pn_socket_getname,
+	.poll		= datagram_poll,
+	.ioctl		= pn_socket_ioctl,
+	.listen		= sock_no_listen,
+	.shutdown	= sock_no_shutdown,
+	.sendmsg	= pn_socket_sendmsg,
+	.recvmsg	= sock_common_recvmsg,
+	.mmap		= sock_no_mmap,
+};
+
+const struct proto_ops phonet_stream_ops = {
+	.family		= AF_PHONET,
+	.owner		= THIS_MODULE,
+	.release	= pn_socket_release,
+	.bind		= pn_socket_bind,
+	.connect	= pn_socket_connect,
+	.socketpair	= sock_no_socketpair,
+	.accept		= pn_socket_accept,
+	.getname	= pn_socket_getname,
+	.poll		= pn_socket_poll,
+	.ioctl		= pn_socket_ioctl,
+	.listen		= pn_socket_listen,
+	.shutdown	= sock_no_shutdown,
+	.setsockopt	= sock_common_setsockopt,
+	.getsockopt	= sock_common_getsockopt,
+	.sendmsg	= pn_socket_sendmsg,
+	.recvmsg	= sock_common_recvmsg,
+	.mmap		= sock_no_mmap,
+};
+EXPORT_SYMBOL(phonet_stream_ops);
+
+/* allocate port for a socket */
+int pn_sock_get_port(struct sock *sk, unsigned short sport)
+{
+	static int port_cur;
+	struct net *net = sock_net(sk);
+	struct pn_sock *pn = pn_sk(sk);
+	struct sockaddr_pn try_sa;
+	struct sock *tmpsk;
+
+	memset(&try_sa, 0, sizeof(struct sockaddr_pn));
+	try_sa.spn_family = AF_PHONET;
+	WARN_ON(!mutex_is_locked(&port_mutex));
+	if (!sport) {
+		/* search free port */
+		int port, pmin, pmax;
+
+		phonet_get_local_port_range(&pmin, &pmax);
+		for (port = pmin; port <= pmax; port++) {
+			port_cur++;
+			if (port_cur < pmin || port_cur > pmax)
+				port_cur = pmin;
+
+			pn_sockaddr_set_port(&try_sa, port_cur);
+			tmpsk = pn_find_sock_by_sa(net, &try_sa);
+			if (tmpsk == NULL) {
+				sport = port_cur;
+				goto found;
+			} else
+				sock_put(tmpsk);
+		}
+	} else {
+		/* try to find specific port */
+		pn_sockaddr_set_port(&try_sa, sport);
+		tmpsk = pn_find_sock_by_sa(net, &try_sa);
+		if (tmpsk == NULL)
+			/* No sock there! We can use that port... */
+			goto found;
+		else
+			sock_put(tmpsk);
+	}
+	/* the port must be in use already */
+	return -EADDRINUSE;
+
+found:
+	pn->sobject = pn_object(pn_addr(pn->sobject), sport);
+	return 0;
+}
+EXPORT_SYMBOL(pn_sock_get_port);
+
+#ifdef CONFIG_PROC_FS
+static struct sock *pn_sock_get_idx(struct seq_file *seq, loff_t pos)
+{
+	struct net *net = seq_file_net(seq);
+	struct hlist_head *hlist = pnsocks.hlist;
+	struct sock *sknode;
+	unsigned int h;
+
+	for (h = 0; h < PN_HASHSIZE; h++) {
+		sk_for_each_rcu(sknode, hlist) {
+			if (!net_eq(net, sock_net(sknode)))
+				continue;
+			if (!pos)
+				return sknode;
+			pos--;
+		}
+		hlist++;
+	}
+	return NULL;
+}
+
+static struct sock *pn_sock_get_next(struct seq_file *seq, struct sock *sk)
+{
+	struct net *net = seq_file_net(seq);
+
+	do
+		sk = sk_next(sk);
+	while (sk && !net_eq(net, sock_net(sk)));
+
+	return sk;
+}
+
+static void *pn_sock_seq_start(struct seq_file *seq, loff_t *pos)
+	__acquires(rcu)
+{
+	rcu_read_lock();
+	return *pos ? pn_sock_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
+}
+
+static void *pn_sock_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct sock *sk;
+
+	if (v == SEQ_START_TOKEN)
+		sk = pn_sock_get_idx(seq, 0);
+	else
+		sk = pn_sock_get_next(seq, v);
+	(*pos)++;
+	return sk;
+}
+
+static void pn_sock_seq_stop(struct seq_file *seq, void *v)
+	__releases(rcu)
+{
+	rcu_read_unlock();
+}
+
+static int pn_sock_seq_show(struct seq_file *seq, void *v)
+{
+	seq_setwidth(seq, 127);
+	if (v == SEQ_START_TOKEN)
+		seq_puts(seq, "pt  loc  rem rs st tx_queue rx_queue "
+			"  uid inode ref pointer drops");
+	else {
+		struct sock *sk = v;
+		struct pn_sock *pn = pn_sk(sk);
+
+		seq_printf(seq, "%2d %04X:%04X:%02X %02X %08X:%08X %5d %llu "
+			"%d %pK %u",
+			sk->sk_protocol, pn->sobject, pn->dobject,
+			pn->resource, sk->sk_state,
+			sk_wmem_alloc_get(sk), sk_rmem_alloc_get(sk),
+			from_kuid_munged(seq_user_ns(seq), sk_uid(sk)),
+			sock_i_ino(sk),
+			refcount_read(&sk->sk_refcnt), sk,
+			sk_drops_read(sk));
+	}
+	seq_pad(seq, '\n');
+	return 0;
+}
+
+const struct seq_operations pn_sock_seq_ops = {
+	.start = pn_sock_seq_start,
+	.next = pn_sock_seq_next,
+	.stop = pn_sock_seq_stop,
+	.show = pn_sock_seq_show,
+};
+#endif
+
+static struct  {
+	struct sock __rcu *sk[256];
+} pnres;
+
+/*
+ * Find and hold socket based on resource.
+ */
+struct sock *pn_find_sock_by_res(struct net *net, u8 res)
+{
+	struct sock *sk;
+
+	if (!net_eq(net, &init_net))
+		return NULL;
+
+	rcu_read_lock();
+	sk = rcu_dereference(pnres.sk[res]);
+	if (sk)
+		sock_hold(sk);
+	rcu_read_unlock();
+	return sk;
+}
+
+static DEFINE_MUTEX(resource_mutex);
+
+int pn_sock_bind_res(struct sock *sk, u8 res)
+{
+	int ret = -EADDRINUSE;
+
+	if (!net_eq(sock_net(sk), &init_net))
+		return -ENOIOCTLCMD;
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+	if (pn_socket_autobind(sk->sk_socket))
+		return -EAGAIN;
+
+	mutex_lock(&resource_mutex);
+	if (pnres.sk[res] == NULL) {
+		sock_hold(sk);
+		rcu_assign_pointer(pnres.sk[res], sk);
+		ret = 0;
+	}
+	mutex_unlock(&resource_mutex);
+	return ret;
+}
+
+int pn_sock_unbind_res(struct sock *sk, u8 res)
+{
+	int ret = -ENOENT;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	mutex_lock(&resource_mutex);
+	if (rcu_access_pointer(pnres.sk[res]) == sk) {
+		RCU_INIT_POINTER(pnres.sk[res], NULL);
+		ret = 0;
+	}
+	mutex_unlock(&resource_mutex);
+
+	if (ret == 0) {
+		synchronize_rcu();
+		sock_put(sk);
+	}
+	return ret;
+}
+
+void pn_sock_unbind_all_res(struct sock *sk)
+{
+	unsigned int res, match = 0;
+
+	mutex_lock(&resource_mutex);
+	for (res = 0; res < 256; res++) {
+		if (rcu_access_pointer(pnres.sk[res]) == sk) {
+			RCU_INIT_POINTER(pnres.sk[res], NULL);
+			match++;
+		}
+	}
+	mutex_unlock(&resource_mutex);
+
+	while (match > 0) {
+		__sock_put(sk);
+		match--;
+	}
+	/* Caller is responsible for RCU sync before final sock_put() */
+}
+
+#ifdef CONFIG_PROC_FS
+static struct sock __rcu **pn_res_get_idx(struct seq_file *seq, loff_t pos)
+{
+	struct net *net = seq_file_net(seq);
+	unsigned int i;
+
+	if (!net_eq(net, &init_net))
+		return NULL;
+
+	for (i = 0; i < 256; i++) {
+		if (rcu_access_pointer(pnres.sk[i]) == NULL)
+			continue;
+		if (!pos)
+			return pnres.sk + i;
+		pos--;
+	}
+	return NULL;
+}
+
+static struct sock __rcu **pn_res_get_next(struct seq_file *seq, struct sock __rcu **sk)
+{
+	struct net *net = seq_file_net(seq);
+	unsigned int i;
+
+	BUG_ON(!net_eq(net, &init_net));
+
+	for (i = (sk - pnres.sk) + 1; i < 256; i++)
+		if (pnres.sk[i])
+			return pnres.sk + i;
+	return NULL;
+}
+
+static void *pn_res_seq_start(struct seq_file *seq, loff_t *pos)
+	__acquires(resource_mutex)
+{
+	mutex_lock(&resource_mutex);
+	return *pos ? pn_res_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
+}
+
+static void *pn_res_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct sock __rcu **sk;
+
+	if (v == SEQ_START_TOKEN)
+		sk = pn_res_get_idx(seq, 0);
+	else
+		sk = pn_res_get_next(seq, v);
+	(*pos)++;
+	return sk;
+}
+
+static void pn_res_seq_stop(struct seq_file *seq, void *v)
+	__releases(resource_mutex)
+{
+	mutex_unlock(&resource_mutex);
+}
+
+static int pn_res_seq_show(struct seq_file *seq, void *v)
+{
+	seq_setwidth(seq, 63);
+	if (v == SEQ_START_TOKEN) {
+		seq_puts(seq, "rs   uid inode");
+	} else {
+		struct sock __rcu **psk = v;
+		struct sock *sk = rcu_dereference_protected(*psk,
+					lockdep_is_held(&resource_mutex));
+
+		seq_printf(seq, "%02X %5u %llu",
+			   (int) (psk - pnres.sk),
+			   from_kuid_munged(seq_user_ns(seq), sk_uid(sk)),
+			   sock_i_ino(sk));
+	}
+	seq_pad(seq, '\n');
+	return 0;
+}
+
+const struct seq_operations pn_res_seq_ops = {
+	.start = pn_res_seq_start,
+	.next = pn_res_seq_next,
+	.stop = pn_res_seq_stop,
+	.show = pn_res_seq_show,
+};
+#endif