1 files changed, 1213 insertions, 223 deletions

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index c0353d55d56..e6fac7e3db5 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -3,6 +3,7 @@
  *
  * 		Authors:	Alan Cox <alan@lxorguk.ukuu.org.uk>
  * 				Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
+ * 				Patrick McHardy <kaber@trash.net>
  *
  *		This program is free software; you can redistribute it and/or
  *		modify it under the terms of the GNU General Public License
@@ -55,93 +56,55 @@
 #include <linux/types.h>
 #include <linux/audit.h>
 #include <linux/mutex.h>
+#include <linux/vmalloc.h>
+#include <linux/if_arp.h>
+#include <asm/cacheflush.h>
 
 #include <net/net_namespace.h>
 #include <net/sock.h>
 #include <net/scm.h>
 #include <net/netlink.h>
 
-#define NLGRPSZ(x)	(ALIGN(x, sizeof(unsigned long) * 8) / 8)
-#define NLGRPLONGS(x)	(NLGRPSZ(x)/sizeof(unsigned long))
-
-struct netlink_sock {
-	/* struct sock has to be the first member of netlink_sock */
-	struct sock		sk;
-	u32			portid;
-	u32			dst_portid;
-	u32			dst_group;
-	u32			flags;
-	u32			subscriptions;
-	u32			ngroups;
-	unsigned long		*groups;
-	unsigned long		state;
-	wait_queue_head_t	wait;
-	struct netlink_callback	*cb;
-	struct mutex		*cb_mutex;
-	struct mutex		cb_def_mutex;
-	void			(*netlink_rcv)(struct sk_buff *skb);
-	void			(*netlink_bind)(int group);
-	struct module		*module;
-};
+#include "af_netlink.h"
 
 struct listeners {
 	struct rcu_head		rcu;
 	unsigned long		masks[0];
 };
 
+/* state bits */
+#define NETLINK_CONGESTED	0x0
+
+/* flags */
 #define NETLINK_KERNEL_SOCKET	0x1
 #define NETLINK_RECV_PKTINFO	0x2
 #define NETLINK_BROADCAST_SEND_ERROR	0x4
 #define NETLINK_RECV_NO_ENOBUFS	0x8
 
-static inline struct netlink_sock *nlk_sk(struct sock *sk)
-{
-	return container_of(sk, struct netlink_sock, sk);
-}
-
 static inline int netlink_is_kernel(struct sock *sk)
 {
 	return nlk_sk(sk)->flags & NETLINK_KERNEL_SOCKET;
 }
 
-struct nl_portid_hash {
-	struct hlist_head	*table;
-	unsigned long		rehash_time;
-
-	unsigned int		mask;
-	unsigned int		shift;
-
-	unsigned int		entries;
-	unsigned int		max_shift;
-
-	u32			rnd;
-};
-
-struct netlink_table {
-	struct nl_portid_hash	hash;
-	struct hlist_head	mc_list;
-	struct listeners __rcu	*listeners;
-	unsigned int		flags;
-	unsigned int		groups;
-	struct mutex		*cb_mutex;
-	struct module		*module;
-	void			(*bind)(int group);
-	int			registered;
-};
-
-static struct netlink_table *nl_table;
+struct netlink_table *nl_table;
+EXPORT_SYMBOL_GPL(nl_table);
 
 static DECLARE_WAIT_QUEUE_HEAD(nl_table_wait);
 
 static int netlink_dump(struct sock *sk);
+static void netlink_skb_destructor(struct sk_buff *skb);
 
-static DEFINE_RWLOCK(nl_table_lock);
+DEFINE_RWLOCK(nl_table_lock);
+EXPORT_SYMBOL_GPL(nl_table_lock);
 static atomic_t nl_table_users = ATOMIC_INIT(0);
 
 #define nl_deref_protected(X) rcu_dereference_protected(X, lockdep_is_held(&nl_table_lock));
 
 static ATOMIC_NOTIFIER_HEAD(netlink_chain);
 
+static DEFINE_SPINLOCK(netlink_tap_lock);
+static struct list_head netlink_tap_all __read_mostly;
+
 static inline u32 netlink_group_mask(u32 group)
 {
 	return group ? 1 << (group - 1) : 0;
@@ -152,31 +115,810 @@ static inline struct hlist_head *nl_portid_hashfn(struct nl_portid_hash *hash, u
 	return &hash->table[jhash_1word(portid, hash->rnd) & hash->mask];
 }
 
-static void netlink_destroy_callback(struct netlink_callback *cb)
+int netlink_add_tap(struct netlink_tap *nt)
+{
+	if (unlikely(nt->dev->type != ARPHRD_NETLINK))
+		return -EINVAL;
+
+	spin_lock(&netlink_tap_lock);
+	list_add_rcu(&nt->list, &netlink_tap_all);
+	spin_unlock(&netlink_tap_lock);
+
+	if (nt->module)
+		__module_get(nt->module);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(netlink_add_tap);
+
+static int __netlink_remove_tap(struct netlink_tap *nt)
 {
-	kfree_skb(cb->skb);
-	kfree(cb);
+	bool found = false;
+	struct netlink_tap *tmp;
+
+	spin_lock(&netlink_tap_lock);
+
+	list_for_each_entry(tmp, &netlink_tap_all, list) {
+		if (nt == tmp) {
+			list_del_rcu(&nt->list);
+			found = true;
+			goto out;
+		}
+	}
+
+	pr_warn("__netlink_remove_tap: %p not found\n", nt);
+out:
+	spin_unlock(&netlink_tap_lock);
+
+	if (found && nt->module)
+		module_put(nt->module);
+
+	return found ? 0 : -ENODEV;
 }
 
-static void netlink_consume_callback(struct netlink_callback *cb)
+int netlink_remove_tap(struct netlink_tap *nt)
 {
-	consume_skb(cb->skb);
-	kfree(cb);
+	int ret;
+
+	ret = __netlink_remove_tap(nt);
+	synchronize_net();
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(netlink_remove_tap);
+
+static bool netlink_filter_tap(const struct sk_buff *skb)
+{
+	struct sock *sk = skb->sk;
+	bool pass = false;
+
+	/* We take the more conservative approach and
+	 * whitelist socket protocols that may pass.
+	 */
+	switch (sk->sk_protocol) {
+	case NETLINK_ROUTE:
+	case NETLINK_USERSOCK:
+	case NETLINK_SOCK_DIAG:
+	case NETLINK_NFLOG:
+	case NETLINK_XFRM:
+	case NETLINK_FIB_LOOKUP:
+	case NETLINK_NETFILTER:
+	case NETLINK_GENERIC:
+		pass = true;
+		break;
+	}
+
+	return pass;
+}
+
+static int __netlink_deliver_tap_skb(struct sk_buff *skb,
+				     struct net_device *dev)
+{
+	struct sk_buff *nskb;
+	struct sock *sk = skb->sk;
+	int ret = -ENOMEM;
+
+	dev_hold(dev);
+	nskb = skb_clone(skb, GFP_ATOMIC);
+	if (nskb) {
+		nskb->dev = dev;
+		nskb->protocol = htons((u16) sk->sk_protocol);
+		nskb->pkt_type = netlink_is_kernel(sk) ?
+				 PACKET_KERNEL : PACKET_USER;
+
+		ret = dev_queue_xmit(nskb);
+		if (unlikely(ret > 0))
+			ret = net_xmit_errno(ret);
+	}
+
+	dev_put(dev);
+	return ret;
+}
+
+static void __netlink_deliver_tap(struct sk_buff *skb)
+{
+	int ret;
+	struct netlink_tap *tmp;
+
+	if (!netlink_filter_tap(skb))
+		return;
+
+	list_for_each_entry_rcu(tmp, &netlink_tap_all, list) {
+		ret = __netlink_deliver_tap_skb(skb, tmp->dev);
+		if (unlikely(ret))
+			break;
+	}
+}
+
+static void netlink_deliver_tap(struct sk_buff *skb)
+{
+	rcu_read_lock();
+
+	if (unlikely(!list_empty(&netlink_tap_all)))
+		__netlink_deliver_tap(skb);
+
+	rcu_read_unlock();
+}
+
+static void netlink_deliver_tap_kernel(struct sock *dst, struct sock *src,
+				       struct sk_buff *skb)
+{
+	if (!(netlink_is_kernel(dst) && netlink_is_kernel(src)))
+		netlink_deliver_tap(skb);
+}
+
+static void netlink_overrun(struct sock *sk)
+{
+	struct netlink_sock *nlk = nlk_sk(sk);
+
+	if (!(nlk->flags & NETLINK_RECV_NO_ENOBUFS)) {
+		if (!test_and_set_bit(NETLINK_CONGESTED, &nlk_sk(sk)->state)) {
+			sk->sk_err = ENOBUFS;
+			sk->sk_error_report(sk);
+		}
+	}
+	atomic_inc(&sk->sk_drops);
+}
+
+static void netlink_rcv_wake(struct sock *sk)
+{
+	struct netlink_sock *nlk = nlk_sk(sk);
+
+	if (skb_queue_empty(&sk->sk_receive_queue))
+		clear_bit(NETLINK_CONGESTED, &nlk->state);
+	if (!test_bit(NETLINK_CONGESTED, &nlk->state))
+		wake_up_interruptible(&nlk->wait);
+}
+
+#ifdef CONFIG_NETLINK_MMAP
+static bool netlink_skb_is_mmaped(const struct sk_buff *skb)
+{
+	return NETLINK_CB(skb).flags & NETLINK_SKB_MMAPED;
+}
+
+static bool netlink_rx_is_mmaped(struct sock *sk)
+{
+	return nlk_sk(sk)->rx_ring.pg_vec != NULL;
+}
+
+static bool netlink_tx_is_mmaped(struct sock *sk)
+{
+	return nlk_sk(sk)->tx_ring.pg_vec != NULL;
+}
+
+static __pure struct page *pgvec_to_page(const void *addr)
+{
+	if (is_vmalloc_addr(addr))
+		return vmalloc_to_page(addr);
+	else
+		return virt_to_page(addr);
+}
+
+static void free_pg_vec(void **pg_vec, unsigned int order, unsigned int len)
+{
+	unsigned int i;
+
+	for (i = 0; i < len; i++) {
+		if (pg_vec[i] != NULL) {
+			if (is_vmalloc_addr(pg_vec[i]))
+				vfree(pg_vec[i]);
+			else
+				free_pages((unsigned long)pg_vec[i], order);
+		}
+	}
+	kfree(pg_vec);
+}
+
+static void *alloc_one_pg_vec_page(unsigned long order)
+{
+	void *buffer;
+	gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP | __GFP_ZERO |
+			  __GFP_NOWARN | __GFP_NORETRY;
+
+	buffer = (void *)__get_free_pages(gfp_flags, order);
+	if (buffer != NULL)
+		return buffer;
+
+	buffer = vzalloc((1 << order) * PAGE_SIZE);
+	if (buffer != NULL)
+		return buffer;
+
+	gfp_flags &= ~__GFP_NORETRY;
+	return (void *)__get_free_pages(gfp_flags, order);
+}
+
+static void **alloc_pg_vec(struct netlink_sock *nlk,
+			   struct nl_mmap_req *req, unsigned int order)
+{
+	unsigned int block_nr = req->nm_block_nr;
+	unsigned int i;
+	void **pg_vec;
+
+	pg_vec = kcalloc(block_nr, sizeof(void *), GFP_KERNEL);
+	if (pg_vec == NULL)
+		return NULL;
+
+	for (i = 0; i < block_nr; i++) {
+		pg_vec[i] = alloc_one_pg_vec_page(order);
+		if (pg_vec[i] == NULL)
+			goto err1;
+	}
+
+	return pg_vec;
+err1:
+	free_pg_vec(pg_vec, order, block_nr);
+	return NULL;
+}
+
+static int netlink_set_ring(struct sock *sk, struct nl_mmap_req *req,
+			    bool closing, bool tx_ring)
+{
+	struct netlink_sock *nlk = nlk_sk(sk);
+	struct netlink_ring *ring;
+	struct sk_buff_head *queue;
+	void **pg_vec = NULL;
+	unsigned int order = 0;
+	int err;
+
+	ring  = tx_ring ? &nlk->tx_ring : &nlk->rx_ring;
+	queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
+
+	if (!closing) {
+		if (atomic_read(&nlk->mapped))
+			return -EBUSY;
+		if (atomic_read(&ring->pending))
+			return -EBUSY;
+	}
+
+	if (req->nm_block_nr) {
+		if (ring->pg_vec != NULL)
+			return -EBUSY;
+
+		if ((int)req->nm_block_size <= 0)
+			return -EINVAL;
+		if (!IS_ALIGNED(req->nm_block_size, PAGE_SIZE))
+			return -EINVAL;
+		if (req->nm_frame_size < NL_MMAP_HDRLEN)
+			return -EINVAL;
+		if (!IS_ALIGNED(req->nm_frame_size, NL_MMAP_MSG_ALIGNMENT))
+			return -EINVAL;
+
+		ring->frames_per_block = req->nm_block_size /
+					 req->nm_frame_size;
+		if (ring->frames_per_block == 0)
+			return -EINVAL;
+		if (ring->frames_per_block * req->nm_block_nr !=
+		    req->nm_frame_nr)
+			return -EINVAL;
+
+		order = get_order(req->nm_block_size);
+		pg_vec = alloc_pg_vec(nlk, req, order);
+		if (pg_vec == NULL)
+			return -ENOMEM;
+	} else {
+		if (req->nm_frame_nr)
+			return -EINVAL;
+	}
+
+	err = -EBUSY;
+	mutex_lock(&nlk->pg_vec_lock);
+	if (closing || atomic_read(&nlk->mapped) == 0) {
+		err = 0;
+		spin_lock_bh(&queue->lock);
+
+		ring->frame_max		= req->nm_frame_nr - 1;
+		ring->head		= 0;
+		ring->frame_size	= req->nm_frame_size;
+		ring->pg_vec_pages	= req->nm_block_size / PAGE_SIZE;
+
+		swap(ring->pg_vec_len, req->nm_block_nr);
+		swap(ring->pg_vec_order, order);
+		swap(ring->pg_vec, pg_vec);
+
+		__skb_queue_purge(queue);
+		spin_unlock_bh(&queue->lock);
+
+		WARN_ON(atomic_read(&nlk->mapped));
+	}
+	mutex_unlock(&nlk->pg_vec_lock);
+
+	if (pg_vec)
+		free_pg_vec(pg_vec, order, req->nm_block_nr);
+	return err;
+}
+
+static void netlink_mm_open(struct vm_area_struct *vma)
+{
+	struct file *file = vma->vm_file;
+	struct socket *sock = file->private_data;
+	struct sock *sk = sock->sk;
+
+	if (sk)
+		atomic_inc(&nlk_sk(sk)->mapped);
+}
+
+static void netlink_mm_close(struct vm_area_struct *vma)
+{
+	struct file *file = vma->vm_file;
+	struct socket *sock = file->private_data;
+	struct sock *sk = sock->sk;
+
+	if (sk)
+		atomic_dec(&nlk_sk(sk)->mapped);
+}
+
+static const struct vm_operations_struct netlink_mmap_ops = {
+	.open	= netlink_mm_open,
+	.close	= netlink_mm_close,
+};
+
+static int netlink_mmap(struct file *file, struct socket *sock,
+			struct vm_area_struct *vma)
+{
+	struct sock *sk = sock->sk;
+	struct netlink_sock *nlk = nlk_sk(sk);
+	struct netlink_ring *ring;
+	unsigned long start, size, expected;
+	unsigned int i;
+	int err = -EINVAL;
+
+	if (vma->vm_pgoff)
+		return -EINVAL;
+
+	mutex_lock(&nlk->pg_vec_lock);
+
+	expected = 0;
+	for (ring = &nlk->rx_ring; ring <= &nlk->tx_ring; ring++) {
+		if (ring->pg_vec == NULL)
+			continue;
+		expected += ring->pg_vec_len * ring->pg_vec_pages * PAGE_SIZE;
+	}
+
+	if (expected == 0)
+		goto out;
+
+	size = vma->vm_end - vma->vm_start;
+	if (size != expected)
+		goto out;
+
+	start = vma->vm_start;
+	for (ring = &nlk->rx_ring; ring <= &nlk->tx_ring; ring++) {
+		if (ring->pg_vec == NULL)
+			continue;
+
+		for (i = 0; i < ring->pg_vec_len; i++) {
+			struct page *page;
+			void *kaddr = ring->pg_vec[i];
+			unsigned int pg_num;
+
+			for (pg_num = 0; pg_num < ring->pg_vec_pages; pg_num++) {
+				page = pgvec_to_page(kaddr);
+				err = vm_insert_page(vma, start, page);
+				if (err < 0)
+					goto out;
+				start += PAGE_SIZE;
+				kaddr += PAGE_SIZE;
+			}
+		}
+	}
+
+	atomic_inc(&nlk->mapped);
+	vma->vm_ops = &netlink_mmap_ops;
+	err = 0;
+out:
+	mutex_unlock(&nlk->pg_vec_lock);
+	return err;
+}
+
+static void netlink_frame_flush_dcache(const struct nl_mmap_hdr *hdr)
+{
+#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
+	struct page *p_start, *p_end;
+
+	/* First page is flushed through netlink_{get,set}_status */
+	p_start = pgvec_to_page(hdr + PAGE_SIZE);
+	p_end   = pgvec_to_page((void *)hdr + NL_MMAP_HDRLEN + hdr->nm_len - 1);
+	while (p_start <= p_end) {
+		flush_dcache_page(p_start);
+		p_start++;
+	}
+#endif
+}
+
+static enum nl_mmap_status netlink_get_status(const struct nl_mmap_hdr *hdr)
+{
+	smp_rmb();
+	flush_dcache_page(pgvec_to_page(hdr));
+	return hdr->nm_status;
+}
+
+static void netlink_set_status(struct nl_mmap_hdr *hdr,
+			       enum nl_mmap_status status)
+{
+	hdr->nm_status = status;
+	flush_dcache_page(pgvec_to_page(hdr));
+	smp_wmb();
+}
+
+static struct nl_mmap_hdr *
+__netlink_lookup_frame(const struct netlink_ring *ring, unsigned int pos)
+{
+	unsigned int pg_vec_pos, frame_off;
+
+	pg_vec_pos = pos / ring->frames_per_block;
+	frame_off  = pos % ring->frames_per_block;
+
+	return ring->pg_vec[pg_vec_pos] + (frame_off * ring->frame_size);
+}
+
+static struct nl_mmap_hdr *
+netlink_lookup_frame(const struct netlink_ring *ring, unsigned int pos,
+		     enum nl_mmap_status status)
+{
+	struct nl_mmap_hdr *hdr;
+
+	hdr = __netlink_lookup_frame(ring, pos);
+	if (netlink_get_status(hdr) != status)
+		return NULL;
+
+	return hdr;
+}
+
+static struct nl_mmap_hdr *
+netlink_current_frame(const struct netlink_ring *ring,
+		      enum nl_mmap_status status)
+{
+	return netlink_lookup_frame(ring, ring->head, status);
+}
+
+static struct nl_mmap_hdr *
+netlink_previous_frame(const struct netlink_ring *ring,
+		       enum nl_mmap_status status)
+{
+	unsigned int prev;
+
+	prev = ring->head ? ring->head - 1 : ring->frame_max;
+	return netlink_lookup_frame(ring, prev, status);
+}
+
+static void netlink_increment_head(struct netlink_ring *ring)
+{
+	ring->head = ring->head != ring->frame_max ? ring->head + 1 : 0;
+}
+
+static void netlink_forward_ring(struct netlink_ring *ring)
+{
+	unsigned int head = ring->head, pos = head;
+	const struct nl_mmap_hdr *hdr;
+
+	do {
+		hdr = __netlink_lookup_frame(ring, pos);
+		if (hdr->nm_status == NL_MMAP_STATUS_UNUSED)
+			break;
+		if (hdr->nm_status != NL_MMAP_STATUS_SKIP)
+			break;
+		netlink_increment_head(ring);
+	} while (ring->head != head);
+}
+
+static bool netlink_dump_space(struct netlink_sock *nlk)
+{
+	struct netlink_ring *ring = &nlk->rx_ring;
+	struct nl_mmap_hdr *hdr;
+	unsigned int n;
+
+	hdr = netlink_current_frame(ring, NL_MMAP_STATUS_UNUSED);
+	if (hdr == NULL)
+		return false;
+
+	n = ring->head + ring->frame_max / 2;
+	if (n > ring->frame_max)
+		n -= ring->frame_max;
+
+	hdr = __netlink_lookup_frame(ring, n);
+
+	return hdr->nm_status == NL_MMAP_STATUS_UNUSED;
+}
+
+static unsigned int netlink_poll(struct file *file, struct socket *sock,
+				 poll_table *wait)
+{
+	struct sock *sk = sock->sk;
+	struct netlink_sock *nlk = nlk_sk(sk);
+	unsigned int mask;
+	int err;
+
+	if (nlk->rx_ring.pg_vec != NULL) {
+		/* Memory mapped sockets don't call recvmsg(), so flow control
+		 * for dumps is performed here. A dump is allowed to continue
+		 * if at least half the ring is unused.
+		 */
+		while (nlk->cb_running && netlink_dump_space(nlk)) {
+			err = netlink_dump(sk);
+			if (err < 0) {
+				sk->sk_err = -err;
+				sk->sk_error_report(sk);
+				break;
+			}
+		}
+		netlink_rcv_wake(sk);
+	}
+
+	mask = datagram_poll(file, sock, wait);
+
+	spin_lock_bh(&sk->sk_receive_queue.lock);
+	if (nlk->rx_ring.pg_vec) {
+		netlink_forward_ring(&nlk->rx_ring);
+		if (!netlink_previous_frame(&nlk->rx_ring, NL_MMAP_STATUS_UNUSED))
+			mask |= POLLIN | POLLRDNORM;
+	}
+	spin_unlock_bh(&sk->sk_receive_queue.lock);
+
+	spin_lock_bh(&sk->sk_write_queue.lock);
+	if (nlk->tx_ring.pg_vec) {
+		if (netlink_current_frame(&nlk->tx_ring, NL_MMAP_STATUS_UNUSED))
+			mask |= POLLOUT | POLLWRNORM;
+	}
+	spin_unlock_bh(&sk->sk_write_queue.lock);
+
+	return mask;
+}
+
+static struct nl_mmap_hdr *netlink_mmap_hdr(struct sk_buff *skb)
+{
+	return (struct nl_mmap_hdr *)(skb->head - NL_MMAP_HDRLEN);
+}
+
+static void netlink_ring_setup_skb(struct sk_buff *skb, struct sock *sk,
+				   struct netlink_ring *ring,
+				   struct nl_mmap_hdr *hdr)
+{
+	unsigned int size;
+	void *data;
+
+	size = ring->frame_size - NL_MMAP_HDRLEN;
+	data = (void *)hdr + NL_MMAP_HDRLEN;
+
+	skb->head	= data;
+	skb->data	= data;
+	skb_reset_tail_pointer(skb);
+	skb->end	= skb->tail + size;
+	skb->len	= 0;
+
+	skb->destructor	= netlink_skb_destructor;
+	NETLINK_CB(skb).flags |= NETLINK_SKB_MMAPED;
+	NETLINK_CB(skb).sk = sk;
+}
+
+static int netlink_mmap_sendmsg(struct sock *sk, struct msghdr *msg,
+				u32 dst_portid, u32 dst_group,
+				struct sock_iocb *siocb)
+{
+	struct netlink_sock *nlk = nlk_sk(sk);
+	struct netlink_ring *ring;
+	struct nl_mmap_hdr *hdr;
+	struct sk_buff *skb;
+	unsigned int maxlen;
+	bool excl = true;
+	int err = 0, len = 0;
+
+	/* Netlink messages are validated by the receiver before processing.
+	 * In order to avoid userspace changing the contents of the message
+	 * after validation, the socket and the ring may only be used by a
+	 * single process, otherwise we fall back to copying.
+	 */
+	if (atomic_long_read(&sk->sk_socket->file->f_count) > 2 ||
+	    atomic_read(&nlk->mapped) > 1)
+		excl = false;
+
+	mutex_lock(&nlk->pg_vec_lock);
+
+	ring   = &nlk->tx_ring;
+	maxlen = ring->frame_size - NL_MMAP_HDRLEN;
+
+	do {
+		hdr = netlink_current_frame(ring, NL_MMAP_STATUS_VALID);
+		if (hdr == NULL) {
+			if (!(msg->msg_flags & MSG_DONTWAIT) &&
+			    atomic_read(&nlk->tx_ring.pending))
+				schedule();
+			continue;
+		}
+		if (hdr->nm_len > maxlen) {
+			err = -EINVAL;
+			goto out;
+		}
+
+		netlink_frame_flush_dcache(hdr);
+
+		if (likely(dst_portid == 0 && dst_group == 0 && excl)) {
+			skb = alloc_skb_head(GFP_KERNEL);
+			if (skb == NULL) {
+				err = -ENOBUFS;
+				goto out;
+			}
+			sock_hold(sk);
+			netlink_ring_setup_skb(skb, sk, ring, hdr);
+			NETLINK_CB(skb).flags |= NETLINK_SKB_TX;
+			__skb_put(skb, hdr->nm_len);
+			netlink_set_status(hdr, NL_MMAP_STATUS_RESERVED);
+			atomic_inc(&ring->pending);
+		} else {
+			skb = alloc_skb(hdr->nm_len, GFP_KERNEL);
+			if (skb == NULL) {
+				err = -ENOBUFS;
+				goto out;
+			}
+			__skb_put(skb, hdr->nm_len);
+			memcpy(skb->data, (void *)hdr + NL_MMAP_HDRLEN, hdr->nm_len);
+			netlink_set_status(hdr, NL_MMAP_STATUS_UNUSED);
+		}
+
+		netlink_increment_head(ring);
+
+		NETLINK_CB(skb).portid	  = nlk->portid;
+		NETLINK_CB(skb).dst_group = dst_group;
+		NETLINK_CB(skb).creds	  = siocb->scm->creds;
+
+		err = security_netlink_send(sk, skb);
+		if (err) {
+			kfree_skb(skb);
+			goto out;
+		}
+
+		if (unlikely(dst_group)) {
+			atomic_inc(&skb->users);
+			netlink_broadcast(sk, skb, dst_portid, dst_group,
+					  GFP_KERNEL);
+		}
+		err = netlink_unicast(sk, skb, dst_portid,
+				      msg->msg_flags & MSG_DONTWAIT);
+		if (err < 0)
+			goto out;
+		len += err;
+
+	} while (hdr != NULL ||
+		 (!(msg->msg_flags & MSG_DONTWAIT) &&
+		  atomic_read(&nlk->tx_ring.pending)));
+
+	if (len > 0)
+		err = len;
+out:
+	mutex_unlock(&nlk->pg_vec_lock);
+	return err;
+}
+
+static void netlink_queue_mmaped_skb(struct sock *sk, struct sk_buff *skb)
+{
+	struct nl_mmap_hdr *hdr;
+
+	hdr = netlink_mmap_hdr(skb);
+	hdr->nm_len	= skb->len;
+	hdr->nm_group	= NETLINK_CB(skb).dst_group;
+	hdr->nm_pid	= NETLINK_CB(skb).creds.pid;
+	hdr->nm_uid	= from_kuid(sk_user_ns(sk), NETLINK_CB(skb).creds.uid);
+	hdr->nm_gid	= from_kgid(sk_user_ns(sk), NETLINK_CB(skb).creds.gid);
+	netlink_frame_flush_dcache(hdr);
+	netlink_set_status(hdr, NL_MMAP_STATUS_VALID);
+
+	NETLINK_CB(skb).flags |= NETLINK_SKB_DELIVERED;
+	kfree_skb(skb);
+}
+
+static void netlink_ring_set_copied(struct sock *sk, struct sk_buff *skb)
+{
+	struct netlink_sock *nlk = nlk_sk(sk);
+	struct netlink_ring *ring = &nlk->rx_ring;
+	struct nl_mmap_hdr *hdr;
+
+	spin_lock_bh(&sk->sk_receive_queue.lock);
+	hdr = netlink_current_frame(ring, NL_MMAP_STATUS_UNUSED);
+	if (hdr == NULL) {
+		spin_unlock_bh(&sk->sk_receive_queue.lock);
+		kfree_skb(skb);
+		netlink_overrun(sk);
+		return;
+	}
+	netlink_increment_head(ring);
+	__skb_queue_tail(&sk->sk_receive_queue, skb);
+	spin_unlock_bh(&sk->sk_receive_queue.lock);
+
+	hdr->nm_len	= skb->len;
+	hdr->nm_group	= NETLINK_CB(skb).dst_group;
+	hdr->nm_pid	= NETLINK_CB(skb).creds.pid;
+	hdr->nm_uid	= from_kuid(sk_user_ns(sk), NETLINK_CB(skb).creds.uid);
+	hdr->nm_gid	= from_kgid(sk_user_ns(sk), NETLINK_CB(skb).creds.gid);
+	netlink_set_status(hdr, NL_MMAP_STATUS_COPY);
+}
+
+#else /* CONFIG_NETLINK_MMAP */
+#define netlink_skb_is_mmaped(skb)	false
+#define netlink_rx_is_mmaped(sk)	false
+#define netlink_tx_is_mmaped(sk)	false
+#define netlink_mmap			sock_no_mmap
+#define netlink_poll			datagram_poll
+#define netlink_mmap_sendmsg(sk, msg, dst_portid, dst_group, siocb)	0
+#endif /* CONFIG_NETLINK_MMAP */
+
+static void netlink_skb_destructor(struct sk_buff *skb)
+{
+#ifdef CONFIG_NETLINK_MMAP
+	struct nl_mmap_hdr *hdr;
+	struct netlink_ring *ring;
+	struct sock *sk;
+
+	/* If a packet from the kernel to userspace was freed because of an
+	 * error without being delivered to userspace, the kernel must reset
+	 * the status. In the direction userspace to kernel, the status is
+	 * always reset here after the packet was processed and freed.
+	 */
+	if (netlink_skb_is_mmaped(skb)) {
+		hdr = netlink_mmap_hdr(skb);
+		sk = NETLINK_CB(skb).sk;
+
+		if (NETLINK_CB(skb).flags & NETLINK_SKB_TX) {
+			netlink_set_status(hdr, NL_MMAP_STATUS_UNUSED);
+			ring = &nlk_sk(sk)->tx_ring;
+		} else {
+			if (!(NETLINK_CB(skb).flags & NETLINK_SKB_DELIVERED)) {
+				hdr->nm_len = 0;
+				netlink_set_status(hdr, NL_MMAP_STATUS_VALID);
+			}
+			ring = &nlk_sk(sk)->rx_ring;
+		}
+
+		WARN_ON(atomic_read(&ring->pending) == 0);
+		atomic_dec(&ring->pending);
+		sock_put(sk);
+
+		skb->head = NULL;
+	}
+#endif
+	if (is_vmalloc_addr(skb->head)) {
+		if (!skb->cloned ||
+		    !atomic_dec_return(&(skb_shinfo(skb)->dataref)))
+			vfree(skb->head);
+
+		skb->head = NULL;
+	}
+	if (skb->sk != NULL)
+		sock_rfree(skb);
+}
+
+static void netlink_skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
+{
+	WARN_ON(skb->sk != NULL);
+	skb->sk = sk;
+	skb->destructor = netlink_skb_destructor;
+	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
+	sk_mem_charge(sk, skb->truesize);
 }
 
 static void netlink_sock_destruct(struct sock *sk)
 {
 	struct netlink_sock *nlk = nlk_sk(sk);
 
-	if (nlk->cb) {
-		if (nlk->cb->done)
-			nlk->cb->done(nlk->cb);
+	if (nlk->cb_running) {
+		if (nlk->cb.done)
+			nlk->cb.done(&nlk->cb);
 
-		module_put(nlk->cb->module);
-		netlink_destroy_callback(nlk->cb);
+		module_put(nlk->cb.module);
+		kfree_skb(nlk->cb.skb);
 	}
 
 	skb_queue_purge(&sk->sk_receive_queue);
+#ifdef CONFIG_NETLINK_MMAP
+	if (1) {
+		struct nl_mmap_req req;
+
+		memset(&req, 0, sizeof(req));
+		if (nlk->rx_ring.pg_vec)
+			netlink_set_ring(sk, &req, true, false);
+		memset(&req, 0, sizeof(req));
+		if (nlk->tx_ring.pg_vec)
+			netlink_set_ring(sk, &req, true, true);
+	}
+#endif /* CONFIG_NETLINK_MMAP */
 
 	if (!sock_flag(sk, SOCK_DEAD)) {
 		printk(KERN_ERR "Freeing alive netlink socket %p\n", sk);
@@ -243,17 +985,23 @@ netlink_unlock_table(void)
 		wake_up(&nl_table_wait);
 }
 
+static bool netlink_compare(struct net *net, struct sock *sk)
+{
+	return net_eq(sock_net(sk), net);
+}
+
 static struct sock *netlink_lookup(struct net *net, int protocol, u32 portid)
 {
-	struct nl_portid_hash *hash = &nl_table[protocol].hash;
+	struct netlink_table *table = &nl_table[protocol];
+	struct nl_portid_hash *hash = &table->hash;
 	struct hlist_head *head;
 	struct sock *sk;
-	struct hlist_node *node;
 
 	read_lock(&nl_table_lock);
 	head = nl_portid_hashfn(hash, portid);
-	sk_for_each(sk, node, head) {
-		if (net_eq(sock_net(sk), net) && (nlk_sk(sk)->portid == portid)) {
+	sk_for_each(sk, head) {
+		if (table->compare(net, sk) &&
+		    (nlk_sk(sk)->portid == portid)) {
 			sock_hold(sk);
 			goto found;
 		}
@@ -312,9 +1060,9 @@ static int nl_portid_hash_rehash(struct nl_portid_hash *hash, int grow)
 
 	for (i = 0; i <= omask; i++) {
 		struct sock *sk;
-		struct hlist_node *node, *tmp;
+		struct hlist_node *tmp;
 
-		sk_for_each_safe(sk, node, tmp, &otable[i])
+		sk_for_each_safe(sk, tmp, &otable[i])
 			__sk_add_node(sk, nl_portid_hashfn(hash, nlk_sk(sk)->portid));
 	}
 
@@ -344,7 +1092,6 @@ static void
 netlink_update_listeners(struct sock *sk)
 {
 	struct netlink_table *tbl = &nl_table[sk->sk_protocol];
-	struct hlist_node *node;
 	unsigned long mask;
 	unsigned int i;
 	struct listeners *listeners;
@@ -355,7 +1102,7 @@ netlink_update_listeners(struct sock *sk)
 
 	for (i = 0; i < NLGRPLONGS(tbl->groups); i++) {
 		mask = 0;
-		sk_for_each_bound(sk, node, &tbl->mc_list) {
+		sk_for_each_bound(sk, &tbl->mc_list) {
 			if (i < NLGRPLONGS(nlk_sk(sk)->ngroups))
 				mask |= nlk_sk(sk)->groups[i];
 		}
@@ -367,22 +1114,23 @@ netlink_update_listeners(struct sock *sk)
 
 static int netlink_insert(struct sock *sk, struct net *net, u32 portid)
 {
-	struct nl_portid_hash *hash = &nl_table[sk->sk_protocol].hash;
+	struct netlink_table *table = &nl_table[sk->sk_protocol];
+	struct nl_portid_hash *hash = &table->hash;
 	struct hlist_head *head;
 	int err = -EADDRINUSE;
 	struct sock *osk;
-	struct hlist_node *node;
 	int len;
 
 	netlink_table_grab();
 	head = nl_portid_hashfn(hash, portid);
 	len = 0;
-	sk_for_each(osk, node, head) {
-		if (net_eq(sock_net(osk), net) && (nlk_sk(osk)->portid == portid))
+	sk_for_each(osk, head) {
+		if (table->compare(net, osk) &&
+		    (nlk_sk(osk)->portid == portid))
 			break;
 		len++;
 	}
-	if (node)
+	if (osk)
 		goto err;
 
 	err = -EBUSY;
@@ -443,6 +1191,9 @@ static int __netlink_create(struct net *net, struct socket *sock,
 		mutex_init(nlk->cb_mutex);
 	}
 	init_waitqueue_head(&nlk->wait);
+#ifdef CONFIG_NETLINK_MMAP
+	mutex_init(&nlk->pg_vec_lock);
+#endif
 
 	sk->sk_destruct = netlink_sock_destruct;
 	sk->sk_protocol = protocol;
@@ -455,7 +1206,8 @@ static int netlink_create(struct net *net, struct socket *sock, int protocol,
 	struct module *module = NULL;
 	struct mutex *cb_mutex;
 	struct netlink_sock *nlk;
-	void (*bind)(int group);
+	int (*bind)(int group);
+	void (*unbind)(int group);
 	int err = 0;
 
 	sock->state = SS_UNCONNECTED;
@@ -481,6 +1233,7 @@ static int netlink_create(struct net *net, struct socket *sock, int protocol,
 		err = -EPROTONOSUPPORT;
 	cb_mutex = nl_table[protocol].cb_mutex;
 	bind = nl_table[protocol].bind;
+	unbind = nl_table[protocol].unbind;
 	netlink_unlock_table();
 
 	if (err < 0)
@@ -497,6 +1250,7 @@ static int netlink_create(struct net *net, struct socket *sock, int protocol,
 	nlk = nlk_sk(sock->sk);
 	nlk->module = module;
 	nlk->netlink_bind = bind;
+	nlk->netlink_unbind = unbind;
 out:
 	return err;
 
@@ -550,6 +1304,7 @@ static int netlink_release(struct socket *sock)
 			kfree_rcu(old, rcu);
 			nl_table[sk->sk_protocol].module = NULL;
 			nl_table[sk->sk_protocol].bind = NULL;
+			nl_table[sk->sk_protocol].unbind = NULL;
 			nl_table[sk->sk_protocol].flags = 0;
 			nl_table[sk->sk_protocol].registered = 0;
 		}
@@ -572,10 +1327,10 @@ static int netlink_autobind(struct socket *sock)
 {
 	struct sock *sk = sock->sk;
 	struct net *net = sock_net(sk);
-	struct nl_portid_hash *hash = &nl_table[sk->sk_protocol].hash;
+	struct netlink_table *table = &nl_table[sk->sk_protocol];
+	struct nl_portid_hash *hash = &table->hash;
 	struct hlist_head *head;
 	struct sock *osk;
-	struct hlist_node *node;
 	s32 portid = task_tgid_vnr(current);
 	int err;
 	static s32 rover = -4097;
@@ -584,8 +1339,8 @@ retry:
 	cond_resched();
 	netlink_table_grab();
 	head = nl_portid_hashfn(hash, portid);
-	sk_for_each(osk, node, head) {
-		if (!net_eq(sock_net(osk), net))
+	sk_for_each(osk, head) {
+		if (!table->compare(net, osk))
 			continue;
 		if (nlk_sk(osk)->portid == portid) {
 			/* Bind collision, search negative portid values. */
@@ -609,7 +1364,74 @@ retry:
 	return err;
 }
 
-static inline int netlink_capable(const struct socket *sock, unsigned int flag)
+/**
+ * __netlink_ns_capable - General netlink message capability test
+ * @nsp: NETLINK_CB of the socket buffer holding a netlink command from userspace.
+ * @user_ns: The user namespace of the capability to use
+ * @cap: The capability to use
+ *
+ * Test to see if the opener of the socket we received the message
+ * from had when the netlink socket was created and the sender of the
+ * message has has the capability @cap in the user namespace @user_ns.
+ */
+bool __netlink_ns_capable(const struct netlink_skb_parms *nsp,
+			struct user_namespace *user_ns, int cap)
+{
+	return ((nsp->flags & NETLINK_SKB_DST) ||
+		file_ns_capable(nsp->sk->sk_socket->file, user_ns, cap)) &&
+		ns_capable(user_ns, cap);
+}
+EXPORT_SYMBOL(__netlink_ns_capable);
+
+/**
+ * netlink_ns_capable - General netlink message capability test
+ * @skb: socket buffer holding a netlink command from userspace
+ * @user_ns: The user namespace of the capability to use
+ * @cap: The capability to use
+ *
+ * Test to see if the opener of the socket we received the message
+ * from had when the netlink socket was created and the sender of the
+ * message has has the capability @cap in the user namespace @user_ns.
+ */
+bool netlink_ns_capable(const struct sk_buff *skb,
+			struct user_namespace *user_ns, int cap)
+{
+	return __netlink_ns_capable(&NETLINK_CB(skb), user_ns, cap);
+}
+EXPORT_SYMBOL(netlink_ns_capable);
+
+/**
+ * netlink_capable - Netlink global message capability test
+ * @skb: socket buffer holding a netlink command from userspace
+ * @cap: The capability to use
+ *
+ * Test to see if the opener of the socket we received the message
+ * from had when the netlink socket was created and the sender of the
+ * message has has the capability @cap in all user namespaces.
+ */
+bool netlink_capable(const struct sk_buff *skb, int cap)
+{
+	return netlink_ns_capable(skb, &init_user_ns, cap);
+}
+EXPORT_SYMBOL(netlink_capable);
+
+/**
+ * netlink_net_capable - Netlink network namespace message capability test
+ * @skb: socket buffer holding a netlink command from userspace
+ * @cap: The capability to use
+ *
+ * Test to see if the opener of the socket we received the message
+ * from had when the netlink socket was created and the sender of the
+ * message has has the capability @cap over the network namespace of
+ * the socket we received the message from.
+ */
+bool netlink_net_capable(const struct sk_buff *skb, int cap)
+{
+	return netlink_ns_capable(skb, sock_net(skb->sk)->user_ns, cap);
+}
+EXPORT_SYMBOL(netlink_net_capable);
+
+static inline int netlink_allowed(const struct socket *sock, unsigned int flag)
 {
 	return (nl_table[sock->sk->sk_protocol].flags & flag) ||
 		ns_capable(sock_net(sock->sk)->user_ns, CAP_NET_ADMIN);
@@ -660,6 +1482,19 @@ static int netlink_realloc_groups(struct sock *sk)
 	return err;
 }
 
+static void netlink_unbind(int group, long unsigned int groups,
+			   struct netlink_sock *nlk)
+{
+	int undo;
+
+	if (!nlk->netlink_unbind)
+		return;
+
+	for (undo = 0; undo < group; undo++)
+		if (test_bit(group, &groups))
+			nlk->netlink_unbind(undo);
+}
+
 static int netlink_bind(struct socket *sock, struct sockaddr *addr,
 			int addr_len)
 {
@@ -668,6 +1503,7 @@ static int netlink_bind(struct socket *sock, struct sockaddr *addr,
 	struct netlink_sock *nlk = nlk_sk(sk);
 	struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr;
 	int err;
+	long unsigned int groups = nladdr->nl_groups;
 
 	if (addr_len < sizeof(struct sockaddr_nl))
 		return -EINVAL;
@@ -676,45 +1512,53 @@ static int netlink_bind(struct socket *sock, struct sockaddr *addr,
 		return -EINVAL;
 
 	/* Only superuser is allowed to listen multicasts */
-	if (nladdr->nl_groups) {
-		if (!netlink_capable(sock, NL_CFG_F_NONROOT_RECV))
+	if (groups) {
+		if (!netlink_allowed(sock, NL_CFG_F_NONROOT_RECV))
 			return -EPERM;
 		err = netlink_realloc_groups(sk);
 		if (err)
 			return err;
 	}
 
-	if (nlk->portid) {
+	if (nlk->portid)
 		if (nladdr->nl_pid != nlk->portid)
 			return -EINVAL;
-	} else {
+
+	if (nlk->netlink_bind && groups) {
+		int group;
+
+		for (group = 0; group < nlk->ngroups; group++) {
+			if (!test_bit(group, &groups))
+				continue;
+			err = nlk->netlink_bind(group);
+			if (!err)
+				continue;
+			netlink_unbind(group, groups, nlk);
+			return err;
+		}
+	}
+
+	if (!nlk->portid) {
 		err = nladdr->nl_pid ?
 			netlink_insert(sk, net, nladdr->nl_pid) :
 			netlink_autobind(sock);
-		if (err)
+		if (err) {
+			netlink_unbind(nlk->ngroups - 1, groups, nlk);
 			return err;
+		}
 	}
 
-	if (!nladdr->nl_groups && (nlk->groups == NULL || !(u32)nlk->groups[0]))
+	if (!groups && (nlk->groups == NULL || !(u32)nlk->groups[0]))
 		return 0;
 
 	netlink_table_grab();
 	netlink_update_subscriptions(sk, nlk->subscriptions +
-					 hweight32(nladdr->nl_groups) -
+					 hweight32(groups) -
 					 hweight32(nlk->groups[0]));
-	nlk->groups[0] = (nlk->groups[0] & ~0xffffffffUL) | nladdr->nl_groups;
+	nlk->groups[0] = (nlk->groups[0] & ~0xffffffffUL) | groups;
 	netlink_update_listeners(sk);
 	netlink_table_ungrab();
 
-	if (nlk->netlink_bind && nlk->groups[0]) {
-		int i;
-
-		for (i=0; i<nlk->ngroups; i++) {
-			if (test_bit(i, nlk->groups))
-				nlk->netlink_bind(i);
-		}
-	}
-
 	return 0;
 }
 
@@ -738,8 +1582,8 @@ static int netlink_connect(struct socket *sock, struct sockaddr *addr,
 	if (addr->sa_family != AF_NETLINK)
 		return -EINVAL;
 
-	/* Only superuser is allowed to send multicasts */
-	if (nladdr->nl_groups && !netlink_capable(sock, NL_CFG_F_NONROOT_SEND))
+	if ((nladdr->nl_groups || nladdr->nl_pid) &&
+	    !netlink_allowed(sock, NL_CFG_F_NONROOT_SEND))
 		return -EPERM;
 
 	if (!nlk->portid)
@@ -775,19 +1619,6 @@ static int netlink_getname(struct socket *sock, struct sockaddr *addr,
 	return 0;
 }
 
-static void netlink_overrun(struct sock *sk)
-{
-	struct netlink_sock *nlk = nlk_sk(sk);
-
-	if (!(nlk->flags & NETLINK_RECV_NO_ENOBUFS)) {
-		if (!test_and_set_bit(0, &nlk_sk(sk)->state)) {
-			sk->sk_err = ENOBUFS;
-			sk->sk_error_report(sk);
-		}
-	}
-	atomic_inc(&sk->sk_drops);
-}
-
 static struct sock *netlink_getsockbyportid(struct sock *ssk, u32 portid)
 {
 	struct sock *sock;
@@ -809,7 +1640,7 @@ static struct sock *netlink_getsockbyportid(struct sock *ssk, u32 portid)
 
 struct sock *netlink_getsockbyfilp(struct file *filp)
 {
-	struct inode *inode = filp->f_path.dentry->d_inode;
+	struct inode *inode = file_inode(filp);
 	struct sock *sock;
 
 	if (!S_ISSOCK(inode->i_mode))
@@ -823,6 +1654,33 @@ struct sock *netlink_getsockbyfilp(struct file *filp)
 	return sock;
 }
 
+static struct sk_buff *netlink_alloc_large_skb(unsigned int size,
+					       int broadcast)
+{
+	struct sk_buff *skb;
+	void *data;
+
+	if (size <= NLMSG_GOODSIZE || broadcast)
+		return alloc_skb(size, GFP_KERNEL);
+
+	size = SKB_DATA_ALIGN(size) +
+	       SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
+
+	data = vmalloc(size);
+	if (data == NULL)
+		return NULL;
+
+	skb = build_skb(data, size);
+	if (skb == NULL)
+		vfree(data);
+	else {
+		skb->head_frag = 0;
+		skb->destructor = netlink_skb_destructor;
+	}
+
+	return skb;
+}
+
 /*
  * Attach a skb to a netlink socket.
  * The caller must hold a reference to the destination socket. On error, the
@@ -840,8 +1698,9 @@ int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
 
 	nlk = nlk_sk(sk);
 
-	if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf ||
-	    test_bit(0, &nlk->state)) {
+	if ((atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf ||
+	     test_bit(NETLINK_CONGESTED, &nlk->state)) &&
+	    !netlink_skb_is_mmaped(skb)) {
 		DECLARE_WAITQUEUE(wait, current);
 		if (!*timeo) {
 			if (!ssk || netlink_is_kernel(ssk))
@@ -855,7 +1714,7 @@ int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
 		add_wait_queue(&nlk->wait, &wait);
 
 		if ((atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf ||
-		     test_bit(0, &nlk->state)) &&
+		     test_bit(NETLINK_CONGESTED, &nlk->state)) &&
 		    !sock_flag(sk, SOCK_DEAD))
 			*timeo = schedule_timeout(*timeo);
 
@@ -869,7 +1728,7 @@ int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
 		}
 		return 1;
 	}
-	skb_set_owner_r(skb, sk);
+	netlink_skb_set_owner_r(skb, sk);
 	return 0;
 }
 
@@ -877,8 +1736,17 @@ static int __netlink_sendskb(struct sock *sk, struct sk_buff *skb)
 {
 	int len = skb->len;
 
-	skb_queue_tail(&sk->sk_receive_queue, skb);
-	sk->sk_data_ready(sk, len);
+	netlink_deliver_tap(skb);
+
+#ifdef CONFIG_NETLINK_MMAP
+	if (netlink_skb_is_mmaped(skb))
+		netlink_queue_mmaped_skb(sk, skb);
+	else if (netlink_rx_is_mmaped(sk))
+		netlink_ring_set_copied(sk, skb);
+	else
+#endif /* CONFIG_NETLINK_MMAP */
+		skb_queue_tail(&sk->sk_receive_queue, skb);
+	sk->sk_data_ready(sk);
 	return len;
 }
 
@@ -900,10 +1768,12 @@ static struct sk_buff *netlink_trim(struct sk_buff *skb, gfp_t allocation)
 {
 	int delta;
 
-	skb_orphan(skb);
+	WARN_ON(skb->sk != NULL);
+	if (netlink_skb_is_mmaped(skb))
+		return skb;
 
 	delta = skb->end - skb->tail;
-	if (delta * 2 < skb->truesize)
+	if (is_vmalloc_addr(skb->head) || delta * 2 < skb->truesize)
 		return skb;
 
 	if (skb_shared(skb)) {
@@ -920,16 +1790,6 @@ static struct sk_buff *netlink_trim(struct sk_buff *skb, gfp_t allocation)
 	return skb;
 }
 
-static void netlink_rcv_wake(struct sock *sk)
-{
-	struct netlink_sock *nlk = nlk_sk(sk);
-
-	if (skb_queue_empty(&sk->sk_receive_queue))
-		clear_bit(0, &nlk->state);
-	if (!test_bit(0, &nlk->state))
-		wake_up_interruptible(&nlk->wait);
-}
-
 static int netlink_unicast_kernel(struct sock *sk, struct sk_buff *skb,
 				  struct sock *ssk)
 {
@@ -939,8 +1799,9 @@ static int netlink_unicast_kernel(struct sock *sk, struct sk_buff *skb,
 	ret = -ECONNREFUSED;
 	if (nlk->netlink_rcv != NULL) {
 		ret = skb->len;
-		skb_set_owner_r(skb, sk);
-		NETLINK_CB(skb).ssk = ssk;
+		netlink_skb_set_owner_r(skb, sk);
+		NETLINK_CB(skb).sk = ssk;
+		netlink_deliver_tap_kernel(sk, ssk, skb);
 		nlk->netlink_rcv(skb);
 		consume_skb(skb);
 	} else {
@@ -986,6 +1847,73 @@ retry:
 }
 EXPORT_SYMBOL(netlink_unicast);
 
+struct sk_buff *netlink_alloc_skb(struct sock *ssk, unsigned int size,
+				  u32 dst_portid, gfp_t gfp_mask)
+{
+#ifdef CONFIG_NETLINK_MMAP
+	struct sock *sk = NULL;
+	struct sk_buff *skb;
+	struct netlink_ring *ring;
+	struct nl_mmap_hdr *hdr;
+	unsigned int maxlen;
+
+	sk = netlink_getsockbyportid(ssk, dst_portid);
+	if (IS_ERR(sk))
+		goto out;
+
+	ring = &nlk_sk(sk)->rx_ring;
+	/* fast-path without atomic ops for common case: non-mmaped receiver */
+	if (ring->pg_vec == NULL)
+		goto out_put;
+
+	if (ring->frame_size - NL_MMAP_HDRLEN < size)
+		goto out_put;
+
+	skb = alloc_skb_head(gfp_mask);
+	if (skb == NULL)
+		goto err1;
+
+	spin_lock_bh(&sk->sk_receive_queue.lock);
+	/* check again under lock */
+	if (ring->pg_vec == NULL)
+		goto out_free;
+
+	/* check again under lock */
+	maxlen = ring->frame_size - NL_MMAP_HDRLEN;
+	if (maxlen < size)
+		goto out_free;
+
+	netlink_forward_ring(ring);
+	hdr = netlink_current_frame(ring, NL_MMAP_STATUS_UNUSED);
+	if (hdr == NULL)
+		goto err2;
+	netlink_ring_setup_skb(skb, sk, ring, hdr);
+	netlink_set_status(hdr, NL_MMAP_STATUS_RESERVED);
+	atomic_inc(&ring->pending);
+	netlink_increment_head(ring);
+
+	spin_unlock_bh(&sk->sk_receive_queue.lock);
+	return skb;
+
+err2:
+	kfree_skb(skb);
+	spin_unlock_bh(&sk->sk_receive_queue.lock);
+	netlink_overrun(sk);
+err1:
+	sock_put(sk);
+	return NULL;
+
+out_free:
+	kfree_skb(skb);
+	spin_unlock_bh(&sk->sk_receive_queue.lock);
+out_put:
+	sock_put(sk);
+out:
+#endif
+	return alloc_skb(size, gfp_mask);
+}
+EXPORT_SYMBOL_GPL(netlink_alloc_skb);
+
 int netlink_has_listeners(struct sock *sk, unsigned int group)
 {
 	int res = 0;
@@ -1010,8 +1938,8 @@ static int netlink_broadcast_deliver(struct sock *sk, struct sk_buff *skb)
 	struct netlink_sock *nlk = nlk_sk(sk);
 
 	if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf &&
-	    !test_bit(0, &nlk->state)) {
-		skb_set_owner_r(skb, sk);
+	    !test_bit(NETLINK_CONGESTED, &nlk->state)) {
+		netlink_skb_set_owner_r(skb, sk);
 		__netlink_sendskb(sk, skb);
 		return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1);
 	}
@@ -1101,7 +2029,6 @@ int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb, u32 portid
 {
 	struct net *net = sock_net(ssk);
 	struct netlink_broadcast_data info;
-	struct hlist_node *node;
 	struct sock *sk;
 
 	skb = netlink_trim(skb, allocation);
@@ -1124,7 +2051,7 @@ int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb, u32 portid
 
 	netlink_lock_table();
 
-	sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list)
+	sk_for_each_bound(sk, &nl_table[ssk->sk_protocol].mc_list)
 		do_one_broadcast(sk, &info);
 
 	consume_skb(skb);
@@ -1191,7 +2118,7 @@ out:
  * netlink_set_err - report error to broadcast listeners
  * @ssk: the kernel netlink socket, as returned by netlink_kernel_create()
  * @portid: the PORTID of a process that we want to skip (if any)
- * @groups: the broadcast group that will notice the error
+ * @group: the broadcast group that will notice the error
  * @code: error code, must be negative (as usual in kernelspace)
  *
  * This function returns the number of broadcast listeners that have set the
@@ -1200,7 +2127,6 @@ out:
 int netlink_set_err(struct sock *ssk, u32 portid, u32 group, int code)
 {
 	struct netlink_set_err_data info;
-	struct hlist_node *node;
 	struct sock *sk;
 	int ret = 0;
 
@@ -1212,7 +2138,7 @@ int netlink_set_err(struct sock *ssk, u32 portid, u32 group, int code)
 
 	read_lock(&nl_table_lock);
 
-	sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list)
+	sk_for_each_bound(sk, &nl_table[ssk->sk_protocol].mc_list)
 		ret += do_one_set_err(sk, &info);
 
 	read_unlock(&nl_table_lock);
@@ -1248,7 +2174,8 @@ static int netlink_setsockopt(struct socket *sock, int level, int optname,
 	if (level != SOL_NETLINK)
 		return -ENOPROTOOPT;
 
-	if (optlen >= sizeof(int) &&
+	if (optname != NETLINK_RX_RING && optname != NETLINK_TX_RING &&
+	    optlen >= sizeof(int) &&
 	    get_user(val, (unsigned int __user *)optval))
 		return -EFAULT;
 
@@ -1262,20 +2189,24 @@ static int netlink_setsockopt(struct socket *sock, int level, int optname,
 		break;
 	case NETLINK_ADD_MEMBERSHIP:
 	case NETLINK_DROP_MEMBERSHIP: {
-		if (!netlink_capable(sock, NL_CFG_F_NONROOT_RECV))
+		if (!netlink_allowed(sock, NL_CFG_F_NONROOT_RECV))
 			return -EPERM;
 		err = netlink_realloc_groups(sk);
 		if (err)
 			return err;
 		if (!val || val - 1 >= nlk->ngroups)
 			return -EINVAL;
+		if (optname == NETLINK_ADD_MEMBERSHIP && nlk->netlink_bind) {
+			err = nlk->netlink_bind(val);
+			if (err)
+				return err;
+		}
 		netlink_table_grab();
 		netlink_update_socket_mc(nlk, val,
 					 optname == NETLINK_ADD_MEMBERSHIP);
 		netlink_table_ungrab();
-
-		if (nlk->netlink_bind)
-			nlk->netlink_bind(val);
+		if (optname == NETLINK_DROP_MEMBERSHIP && nlk->netlink_unbind)
+			nlk->netlink_unbind(val);
 
 		err = 0;
 		break;
@@ -1290,13 +2221,32 @@ static int netlink_setsockopt(struct socket *sock, int level, int optname,
 	case NETLINK_NO_ENOBUFS:
 		if (val) {
 			nlk->flags |= NETLINK_RECV_NO_ENOBUFS;
-			clear_bit(0, &nlk->state);
+			clear_bit(NETLINK_CONGESTED, &nlk->state);
 			wake_up_interruptible(&nlk->wait);
 		} else {
 			nlk->flags &= ~NETLINK_RECV_NO_ENOBUFS;
 		}
 		err = 0;
 		break;
+#ifdef CONFIG_NETLINK_MMAP
+	case NETLINK_RX_RING:
+	case NETLINK_TX_RING: {
+		struct nl_mmap_req req;
+
+		/* Rings might consume more memory than queue limits, require
+		 * CAP_NET_ADMIN.
+		 */
+		if (!capable(CAP_NET_ADMIN))
+			return -EPERM;
+		if (optlen < sizeof(req))
+			return -EINVAL;
+		if (copy_from_user(&req, optval, sizeof(req)))
+			return -EFAULT;
+		err = netlink_set_ring(sk, &req, false,
+				       optname == NETLINK_TX_RING);
+		break;
+	}
+#endif /* CONFIG_NETLINK_MMAP */
 	default:
 		err = -ENOPROTOOPT;
 	}
@@ -1369,12 +2319,13 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
 	struct sock_iocb *siocb = kiocb_to_siocb(kiocb);
 	struct sock *sk = sock->sk;
 	struct netlink_sock *nlk = nlk_sk(sk);
-	struct sockaddr_nl *addr = msg->msg_name;
+	DECLARE_SOCKADDR(struct sockaddr_nl *, addr, msg->msg_name);
 	u32 dst_portid;
 	u32 dst_group;
 	struct sk_buff *skb;
 	int err;
 	struct scm_cookie scm;
+	u32 netlink_skb_flags = 0;
 
 	if (msg->msg_flags&MSG_OOB)
 		return -EOPNOTSUPP;
@@ -1394,8 +2345,9 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
 		dst_group = ffs(addr->nl_groups);
 		err =  -EPERM;
 		if ((dst_group || dst_portid) &&
-		    !netlink_capable(sock, NL_CFG_F_NONROOT_SEND))
+		    !netlink_allowed(sock, NL_CFG_F_NONROOT_SEND))
 			goto out;
+		netlink_skb_flags |= NETLINK_SKB_DST;
 	} else {
 		dst_portid = nlk->dst_portid;
 		dst_group = nlk->dst_group;
@@ -1407,17 +2359,25 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
 			goto out;
 	}
 
+	if (netlink_tx_is_mmaped(sk) &&
+	    msg->msg_iov->iov_base == NULL) {
+		err = netlink_mmap_sendmsg(sk, msg, dst_portid, dst_group,
+					   siocb);
+		goto out;
+	}
+
 	err = -EMSGSIZE;
 	if (len > sk->sk_sndbuf - 32)
 		goto out;
 	err = -ENOBUFS;
-	skb = alloc_skb(len, GFP_KERNEL);
+	skb = netlink_alloc_large_skb(len, dst_group);
 	if (skb == NULL)
 		goto out;
 
 	NETLINK_CB(skb).portid	= nlk->portid;
 	NETLINK_CB(skb).dst_group = dst_group;
 	NETLINK_CB(skb).creds	= siocb->scm->creds;
+	NETLINK_CB(skb).flags	= netlink_skb_flags;
 
 	err = -EFAULT;
 	if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
@@ -1483,7 +2443,10 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock,
 	}
 #endif
 
-	msg->msg_namelen = 0;
+	/* Record the max length of recvmsg() calls for future allocations */
+	nlk->max_recvmsg_len = max(nlk->max_recvmsg_len, len);
+	nlk->max_recvmsg_len = min_t(size_t, nlk->max_recvmsg_len,
+				     16384);
 
 	copied = data_skb->len;
 	if (len < copied) {
@@ -1495,7 +2458,7 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock,
 	err = skb_copy_datagram_iovec(data_skb, 0, msg->msg_iov, copied);
 
 	if (msg->msg_name) {
-		struct sockaddr_nl *addr = (struct sockaddr_nl *)msg->msg_name;
+		DECLARE_SOCKADDR(struct sockaddr_nl *, addr, msg->msg_name);
 		addr->nl_family = AF_NETLINK;
 		addr->nl_pad    = 0;
 		addr->nl_pid	= NETLINK_CB(skb).portid;
@@ -1516,10 +2479,11 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock,
 
 	skb_free_datagram(sk, skb);
 
-	if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) {
+	if (nlk->cb_running &&
+	    atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) {
 		ret = netlink_dump(sk);
 		if (ret) {
-			sk->sk_err = ret;
+			sk->sk_err = -ret;
 			sk->sk_error_report(sk);
 		}
 	}
@@ -1530,7 +2494,7 @@ out:
 	return err ? : copied;
 }
 
-static void netlink_data_ready(struct sock *sk, int len)
+static void netlink_data_ready(struct sock *sk)
 {
 	BUG();
 }
@@ -1600,6 +2564,8 @@ __netlink_kernel_create(struct net *net, int unit, struct module *module,
 		if (cfg) {
 			nl_table[unit].bind = cfg->bind;
 			nl_table[unit].flags = cfg->flags;
+			if (cfg->compare)
+				nl_table[unit].compare = cfg->compare;
 		}
 		nl_table[unit].registered = 1;
 	} else {
@@ -1676,42 +2642,26 @@ int netlink_change_ngroups(struct sock *sk, unsigned int groups)
 void __netlink_clear_multicast_users(struct sock *ksk, unsigned int group)
 {
 	struct sock *sk;
-	struct hlist_node *node;
 	struct netlink_table *tbl = &nl_table[ksk->sk_protocol];
 
-	sk_for_each_bound(sk, node, &tbl->mc_list)
+	sk_for_each_bound(sk, &tbl->mc_list)
 		netlink_update_socket_mc(nlk_sk(sk), group, 0);
 }
 
-/**
- * netlink_clear_multicast_users - kick off multicast listeners
- *
- * This function removes all listeners from the given group.
- * @ksk: The kernel netlink socket, as returned by
- *	netlink_kernel_create().
- * @group: The multicast group to clear.
- */
-void netlink_clear_multicast_users(struct sock *ksk, unsigned int group)
-{
-	netlink_table_grab();
-	__netlink_clear_multicast_users(ksk, group);
-	netlink_table_ungrab();
-}
-
 struct nlmsghdr *
 __nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, int type, int len, int flags)
 {
 	struct nlmsghdr *nlh;
-	int size = NLMSG_LENGTH(len);
+	int size = nlmsg_msg_size(len);
 
-	nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size));
+	nlh = (struct nlmsghdr *)skb_put(skb, NLMSG_ALIGN(size));
 	nlh->nlmsg_type = type;
 	nlh->nlmsg_len = size;
 	nlh->nlmsg_flags = flags;
 	nlh->nlmsg_pid = portid;
 	nlh->nlmsg_seq = seq;
 	if (!__builtin_constant_p(size) || NLMSG_ALIGN(size) - size != 0)
-		memset(NLMSG_DATA(nlh) + len, 0, NLMSG_ALIGN(size) - size);
+		memset(nlmsg_data(nlh) + len, 0, NLMSG_ALIGN(size) - size);
 	return nlh;
 }
 EXPORT_SYMBOL(__nlmsg_put);
@@ -1731,18 +2681,41 @@ static int netlink_dump(struct sock *sk)
 	int alloc_size;
 
 	mutex_lock(nlk->cb_mutex);
-
-	cb = nlk->cb;
-	if (cb == NULL) {
+	if (!nlk->cb_running) {
 		err = -EINVAL;
 		goto errout_skb;
 	}
 
+	cb = &nlk->cb;
 	alloc_size = max_t(int, cb->min_dump_alloc, NLMSG_GOODSIZE);
 
-	skb = sock_rmalloc(sk, alloc_size, 0, GFP_KERNEL);
+	if (!netlink_rx_is_mmaped(sk) &&
+	    atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
+		goto errout_skb;
+
+	/* NLMSG_GOODSIZE is small to avoid high order allocations being
+	 * required, but it makes sense to _attempt_ a 16K bytes allocation
+	 * to reduce number of system calls on dump operations, if user
+	 * ever provided a big enough buffer.
+	 */
+	if (alloc_size < nlk->max_recvmsg_len) {
+		skb = netlink_alloc_skb(sk,
+					nlk->max_recvmsg_len,
+					nlk->portid,
+					GFP_KERNEL |
+					__GFP_NOWARN |
+					__GFP_NORETRY);
+		/* available room should be exact amount to avoid MSG_TRUNC */
+		if (skb)
+			skb_reserve(skb, skb_tailroom(skb) -
+					 nlk->max_recvmsg_len);
+	}
+	if (!skb)
+		skb = netlink_alloc_skb(sk, alloc_size, nlk->portid,
+					GFP_KERNEL);
 	if (!skb)
 		goto errout_skb;
+	netlink_skb_set_owner_r(skb, sk);
 
 	len = cb->dump(skb, cb);
 
@@ -1771,11 +2744,11 @@ static int netlink_dump(struct sock *sk)
 
 	if (cb->done)
 		cb->done(cb);
-	nlk->cb = NULL;
-	mutex_unlock(nlk->cb_mutex);
 
+	nlk->cb_running = false;
+	mutex_unlock(nlk->cb_mutex);
 	module_put(cb->module);
-	netlink_consume_callback(cb);
+	consume_skb(cb->skb);
 	return 0;
 
 errout_skb:
@@ -1793,47 +2766,51 @@ int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
 	struct netlink_sock *nlk;
 	int ret;
 
-	cb = kzalloc(sizeof(*cb), GFP_KERNEL);
-	if (cb == NULL)
-		return -ENOBUFS;
-
-	cb->dump = control->dump;
-	cb->done = control->done;
-	cb->nlh = nlh;
-	cb->data = control->data;
-	cb->module = control->module;
-	cb->min_dump_alloc = control->min_dump_alloc;
-	atomic_inc(&skb->users);
-	cb->skb = skb;
+	/* Memory mapped dump requests need to be copied to avoid looping
+	 * on the pending state in netlink_mmap_sendmsg() while the CB hold
+	 * a reference to the skb.
+	 */
+	if (netlink_skb_is_mmaped(skb)) {
+		skb = skb_copy(skb, GFP_KERNEL);
+		if (skb == NULL)
+			return -ENOBUFS;
+	} else
+		atomic_inc(&skb->users);
 
 	sk = netlink_lookup(sock_net(ssk), ssk->sk_protocol, NETLINK_CB(skb).portid);
 	if (sk == NULL) {
-		netlink_destroy_callback(cb);
-		return -ECONNREFUSED;
+		ret = -ECONNREFUSED;
+		goto error_free;
 	}
-	nlk = nlk_sk(sk);
 
+	nlk = nlk_sk(sk);
 	mutex_lock(nlk->cb_mutex);
 	/* A dump is in progress... */
-	if (nlk->cb) {
-		mutex_unlock(nlk->cb_mutex);
-		netlink_destroy_callback(cb);
+	if (nlk->cb_running) {
 		ret = -EBUSY;
-		goto out;
+		goto error_unlock;
 	}
 	/* add reference of module which cb->dump belongs to */
-	if (!try_module_get(cb->module)) {
-		mutex_unlock(nlk->cb_mutex);
-		netlink_destroy_callback(cb);
+	if (!try_module_get(control->module)) {
 		ret = -EPROTONOSUPPORT;
-		goto out;
+		goto error_unlock;
 	}
 
-	nlk->cb = cb;
+	cb = &nlk->cb;
+	memset(cb, 0, sizeof(*cb));
+	cb->dump = control->dump;
+	cb->done = control->done;
+	cb->nlh = nlh;
+	cb->data = control->data;
+	cb->module = control->module;
+	cb->min_dump_alloc = control->min_dump_alloc;
+	cb->skb = skb;
+
+	nlk->cb_running = true;
+
 	mutex_unlock(nlk->cb_mutex);
 
 	ret = netlink_dump(sk);
-out:
 	sock_put(sk);
 
 	if (ret)
@@ -1843,6 +2820,13 @@ out:
 	 * signal not to send ACK even if it was requested.
 	 */
 	return -EINTR;
+
+error_unlock:
+	sock_put(sk);
+	mutex_unlock(nlk->cb_mutex);
+error_free:
+	kfree_skb(skb);
+	return ret;
 }
 EXPORT_SYMBOL(__netlink_dump_start);
 
@@ -1857,7 +2841,8 @@ void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err)
 	if (err)
 		payload += nlmsg_len(nlh);
 
-	skb = nlmsg_new(payload, GFP_KERNEL);
+	skb = netlink_alloc_skb(in_skb->sk, nlmsg_total_size(payload),
+				NETLINK_CB(in_skb).portid, GFP_KERNEL);
 	if (!skb) {
 		struct sock *sk;
 
@@ -1974,14 +2959,13 @@ static struct sock *netlink_seq_socket_idx(struct seq_file *seq, loff_t pos)
 	struct nl_seq_iter *iter = seq->private;
 	int i, j;
 	struct sock *s;
-	struct hlist_node *node;
 	loff_t off = 0;
 
 	for (i = 0; i < MAX_LINKS; i++) {
 		struct nl_portid_hash *hash = &nl_table[i].hash;
 
 		for (j = 0; j <= hash->mask; j++) {
-			sk_for_each(s, node, &hash->table[j]) {
+			sk_for_each(s, &hash->table[j]) {
 				if (sock_net(s) != seq_file_net(seq))
 					continue;
 				if (off == pos) {
@@ -2007,6 +2991,7 @@ static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
 	struct sock *s;
 	struct nl_seq_iter *iter;
+	struct net *net;
 	int i, j;
 
 	++*pos;
@@ -2014,11 +2999,12 @@ static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 	if (v == SEQ_START_TOKEN)
 		return netlink_seq_socket_idx(seq, 0);
 
+	net = seq_file_net(seq);
 	iter = seq->private;
 	s = v;
 	do {
 		s = sk_next(s);
-	} while (s && sock_net(s) != seq_file_net(seq));
+	} while (s && !nl_table[s->sk_protocol].compare(net, s));
 	if (s)
 		return s;
 
@@ -2030,7 +3016,8 @@ static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 
 		for (; j <= hash->mask; j++) {
 			s = sk_head(&hash->table[j]);
-			while (s && sock_net(s) != seq_file_net(seq))
+
+			while (s && !nl_table[s->sk_protocol].compare(net, s))
 				s = sk_next(s);
 			if (s) {
 				iter->link = i;
@@ -2062,14 +3049,14 @@ static int netlink_seq_show(struct seq_file *seq, void *v)
 		struct sock *s = v;
 		struct netlink_sock *nlk = nlk_sk(s);
 
-		seq_printf(seq, "%pK %-3d %-6u %08x %-8d %-8d %pK %-8d %-8d %-8lu\n",
+		seq_printf(seq, "%pK %-3d %-6u %08x %-8d %-8d %d %-8d %-8d %-8lu\n",
 			   s,
 			   s->sk_protocol,
 			   nlk->portid,
 			   nlk->groups ? (u32)nlk->groups[0] : 0,
 			   sk_rmem_alloc_get(s),
 			   sk_wmem_alloc_get(s),
-			   nlk->cb,
+			   nlk->cb_running,
 			   atomic_read(&s->sk_refcnt),
 			   atomic_read(&s->sk_drops),
 			   sock_i_ino(s)
@@ -2124,7 +3111,7 @@ static const struct proto_ops netlink_ops = {
 	.socketpair =	sock_no_socketpair,
 	.accept =	sock_no_accept,
 	.getname =	netlink_getname,
-	.poll =		datagram_poll,
+	.poll =		netlink_poll,
 	.ioctl =	sock_no_ioctl,
 	.listen =	sock_no_listen,
 	.shutdown =	sock_no_shutdown,
@@ -2132,7 +3119,7 @@ static const struct proto_ops netlink_ops = {
 	.getsockopt =	netlink_getsockopt,
 	.sendmsg =	netlink_sendmsg,
 	.recvmsg =	netlink_recvmsg,
-	.mmap =		sock_no_mmap,
+	.mmap =		netlink_mmap,
 	.sendpage =	sock_no_sendpage,
 };
 
@@ -2145,7 +3132,7 @@ static const struct net_proto_family netlink_family_ops = {
 static int __net_init netlink_net_init(struct net *net)
 {
 #ifdef CONFIG_PROC_FS
-	if (!proc_net_fops_create(net, "netlink", 0, &netlink_seq_fops))
+	if (!proc_create("netlink", 0, net->proc_net, &netlink_seq_fops))
 		return -ENOMEM;
 #endif
 	return 0;
@@ -2154,7 +3141,7 @@ static int __net_init netlink_net_init(struct net *net)
 static void __net_exit netlink_net_exit(struct net *net)
 {
 #ifdef CONFIG_PROC_FS
-	proc_net_remove(net, "netlink");
+	remove_proc_entry("netlink", net->proc_net);
 #endif
 }
 
@@ -2185,7 +3172,6 @@ static struct pernet_operations __net_initdata netlink_net_ops = {
 
 static int __init netlink_proto_init(void)
 {
-	struct sk_buff *dummy_skb;
 	int i;
 	unsigned long limit;
 	unsigned int order;
@@ -2194,7 +3180,7 @@ static int __init netlink_proto_init(void)
 	if (err != 0)
 		goto out;
 
-	BUILD_BUG_ON(sizeof(struct netlink_skb_parms) > sizeof(dummy_skb->cb));
+	BUILD_BUG_ON(sizeof(struct netlink_skb_parms) > FIELD_SIZEOF(struct sk_buff, cb));
 
 	nl_table = kcalloc(MAX_LINKS, sizeof(*nl_table), GFP_KERNEL);
 	if (!nl_table)
@@ -2224,8 +3210,12 @@ static int __init netlink_proto_init(void)
 		hash->shift = 0;
 		hash->mask = 0;
 		hash->rehash_time = jiffies;
+
+		nl_table[i].compare = netlink_compare;
 	}
 
+	INIT_LIST_HEAD(&netlink_tap_all);
+
 	netlink_add_usersock_entry();
 
 	sock_register(&netlink_family_ops);