Initial import

1 files changed, 2979 insertions, 0 deletions

diff --git a/net/core/sock.c b/net/core/sock.c
new file mode 100644
index 000000000..dc30dc5bb
--- /dev/null
+++ b/net/core/sock.c
@@ -0,0 +1,2979 @@
+/*
+ * INET		An implementation of the TCP/IP protocol suite for the LINUX
+ *		operating system.  INET is implemented using the  BSD Socket
+ *		interface as the means of communication with the user level.
+ *
+ *		Generic socket support routines. Memory allocators, socket lock/release
+ *		handler for protocols to use and generic option handler.
+ *
+ *
+ * Authors:	Ross Biro
+ *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
+ *		Florian La Roche, <flla@stud.uni-sb.de>
+ *		Alan Cox, <A.Cox@swansea.ac.uk>
+ *
+ * Fixes:
+ *		Alan Cox	: 	Numerous verify_area() problems
+ *		Alan Cox	:	Connecting on a connecting socket
+ *					now returns an error for tcp.
+ *		Alan Cox	:	sock->protocol is set correctly.
+ *					and is not sometimes left as 0.
+ *		Alan Cox	:	connect handles icmp errors on a
+ *					connect properly. Unfortunately there
+ *					is a restart syscall nasty there. I
+ *					can't match BSD without hacking the C
+ *					library. Ideas urgently sought!
+ *		Alan Cox	:	Disallow bind() to addresses that are
+ *					not ours - especially broadcast ones!!
+ *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
+ *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
+ *					instead they leave that for the DESTROY timer.
+ *		Alan Cox	:	Clean up error flag in accept
+ *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
+ *					was buggy. Put a remove_sock() in the handler
+ *					for memory when we hit 0. Also altered the timer
+ *					code. The ACK stuff can wait and needs major
+ *					TCP layer surgery.
+ *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
+ *					and fixed timer/inet_bh race.
+ *		Alan Cox	:	Added zapped flag for TCP
+ *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
+ *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
+ *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
+ *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
+ *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
+ *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
+ *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
+ *	Pauline Middelink	:	identd support
+ *		Alan Cox	:	Fixed connect() taking signals I think.
+ *		Alan Cox	:	SO_LINGER supported
+ *		Alan Cox	:	Error reporting fixes
+ *		Anonymous	:	inet_create tidied up (sk->reuse setting)
+ *		Alan Cox	:	inet sockets don't set sk->type!
+ *		Alan Cox	:	Split socket option code
+ *		Alan Cox	:	Callbacks
+ *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
+ *		Alex		:	Removed restriction on inet fioctl
+ *		Alan Cox	:	Splitting INET from NET core
+ *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
+ *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
+ *		Alan Cox	:	Split IP from generic code
+ *		Alan Cox	:	New kfree_skbmem()
+ *		Alan Cox	:	Make SO_DEBUG superuser only.
+ *		Alan Cox	:	Allow anyone to clear SO_DEBUG
+ *					(compatibility fix)
+ *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
+ *		Alan Cox	:	Allocator for a socket is settable.
+ *		Alan Cox	:	SO_ERROR includes soft errors.
+ *		Alan Cox	:	Allow NULL arguments on some SO_ opts
+ *		Alan Cox	: 	Generic socket allocation to make hooks
+ *					easier (suggested by Craig Metz).
+ *		Michael Pall	:	SO_ERROR returns positive errno again
+ *              Steve Whitehouse:       Added default destructor to free
+ *                                      protocol private data.
+ *              Steve Whitehouse:       Added various other default routines
+ *                                      common to several socket families.
+ *              Chris Evans     :       Call suser() check last on F_SETOWN
+ *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
+ *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
+ *		Andi Kleen	:	Fix write_space callback
+ *		Chris Evans	:	Security fixes - signedness again
+ *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
+ *
+ * To Fix:
+ *
+ *
+ *		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; either version
+ *		2 of the License, or (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/capability.h>
+#include <linux/errno.h>
+#include <linux/errqueue.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/poll.h>
+#include <linux/tcp.h>
+#include <linux/init.h>
+#include <linux/highmem.h>
+#include <linux/user_namespace.h>
+#include <linux/static_key.h>
+#include <linux/memcontrol.h>
+#include <linux/prefetch.h>
+
+#include <asm/uaccess.h>
+
+#include <linux/netdevice.h>
+#include <net/protocol.h>
+#include <linux/skbuff.h>
+#include <net/net_namespace.h>
+#include <net/request_sock.h>
+#include <net/sock.h>
+#include <linux/net_tstamp.h>
+#include <net/xfrm.h>
+#include <linux/ipsec.h>
+#include <net/cls_cgroup.h>
+#include <net/netprio_cgroup.h>
+
+#include <linux/filter.h>
+
+#include <trace/events/sock.h>
+
+#ifdef CONFIG_INET
+#include <net/tcp.h>
+#endif
+
+#include <net/busy_poll.h>
+
+static DEFINE_MUTEX(proto_list_mutex);
+static LIST_HEAD(proto_list);
+
+/**
+ * sk_ns_capable - General socket capability test
+ * @sk: Socket to use a capability on or through
+ * @user_ns: The user namespace of the capability to use
+ * @cap: The capability to use
+ *
+ * Test to see if the opener of the socket had when the socket was
+ * created and the current process has the capability @cap in the user
+ * namespace @user_ns.
+ */
+bool sk_ns_capable(const struct sock *sk,
+		   struct user_namespace *user_ns, int cap)
+{
+	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
+		ns_capable(user_ns, cap);
+}
+EXPORT_SYMBOL(sk_ns_capable);
+
+/**
+ * sk_capable - Socket global capability test
+ * @sk: Socket to use a capability on or through
+ * @cap: The global capability to use
+ *
+ * Test to see if the opener of the socket had when the socket was
+ * created and the current process has the capability @cap in all user
+ * namespaces.
+ */
+bool sk_capable(const struct sock *sk, int cap)
+{
+	return sk_ns_capable(sk, &init_user_ns, cap);
+}
+EXPORT_SYMBOL(sk_capable);
+
+/**
+ * sk_net_capable - Network namespace socket capability test
+ * @sk: Socket to use a capability on or through
+ * @cap: The capability to use
+ *
+ * Test to see if the opener of the socket had when the socket was created
+ * and the current process has the capability @cap over the network namespace
+ * the socket is a member of.
+ */
+bool sk_net_capable(const struct sock *sk, int cap)
+{
+	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
+}
+EXPORT_SYMBOL(sk_net_capable);
+
+
+#ifdef CONFIG_MEMCG_KMEM
+int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
+{
+	struct proto *proto;
+	int ret = 0;
+
+	mutex_lock(&proto_list_mutex);
+	list_for_each_entry(proto, &proto_list, node) {
+		if (proto->init_cgroup) {
+			ret = proto->init_cgroup(memcg, ss);
+			if (ret)
+				goto out;
+		}
+	}
+
+	mutex_unlock(&proto_list_mutex);
+	return ret;
+out:
+	list_for_each_entry_continue_reverse(proto, &proto_list, node)
+		if (proto->destroy_cgroup)
+			proto->destroy_cgroup(memcg);
+	mutex_unlock(&proto_list_mutex);
+	return ret;
+}
+
+void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
+{
+	struct proto *proto;
+
+	mutex_lock(&proto_list_mutex);
+	list_for_each_entry_reverse(proto, &proto_list, node)
+		if (proto->destroy_cgroup)
+			proto->destroy_cgroup(memcg);
+	mutex_unlock(&proto_list_mutex);
+}
+#endif
+
+/*
+ * Each address family might have different locking rules, so we have
+ * one slock key per address family:
+ */
+static struct lock_class_key af_family_keys[AF_MAX];
+static struct lock_class_key af_family_slock_keys[AF_MAX];
+
+#if defined(CONFIG_MEMCG_KMEM)
+struct static_key memcg_socket_limit_enabled;
+EXPORT_SYMBOL(memcg_socket_limit_enabled);
+#endif
+
+/*
+ * Make lock validator output more readable. (we pre-construct these
+ * strings build-time, so that runtime initialization of socket
+ * locks is fast):
+ */
+static const char *const af_family_key_strings[AF_MAX+1] = {
+  "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX"     , "sk_lock-AF_INET"     ,
+  "sk_lock-AF_AX25"  , "sk_lock-AF_IPX"      , "sk_lock-AF_APPLETALK",
+  "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE"   , "sk_lock-AF_ATMPVC"   ,
+  "sk_lock-AF_X25"   , "sk_lock-AF_INET6"    , "sk_lock-AF_ROSE"     ,
+  "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI"  , "sk_lock-AF_SECURITY" ,
+  "sk_lock-AF_KEY"   , "sk_lock-AF_NETLINK"  , "sk_lock-AF_PACKET"   ,
+  "sk_lock-AF_ASH"   , "sk_lock-AF_ECONET"   , "sk_lock-AF_ATMSVC"   ,
+  "sk_lock-AF_RDS"   , "sk_lock-AF_SNA"      , "sk_lock-AF_IRDA"     ,
+  "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE"  , "sk_lock-AF_LLC"      ,
+  "sk_lock-27"       , "sk_lock-28"          , "sk_lock-AF_CAN"      ,
+  "sk_lock-AF_TIPC"  , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV"        ,
+  "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN"     , "sk_lock-AF_PHONET"   ,
+  "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG"      ,
+  "sk_lock-AF_NFC"   , "sk_lock-AF_VSOCK"    , "sk_lock-AF_MAX"
+};
+static const char *const af_family_slock_key_strings[AF_MAX+1] = {
+  "slock-AF_UNSPEC", "slock-AF_UNIX"     , "slock-AF_INET"     ,
+  "slock-AF_AX25"  , "slock-AF_IPX"      , "slock-AF_APPLETALK",
+  "slock-AF_NETROM", "slock-AF_BRIDGE"   , "slock-AF_ATMPVC"   ,
+  "slock-AF_X25"   , "slock-AF_INET6"    , "slock-AF_ROSE"     ,
+  "slock-AF_DECnet", "slock-AF_NETBEUI"  , "slock-AF_SECURITY" ,
+  "slock-AF_KEY"   , "slock-AF_NETLINK"  , "slock-AF_PACKET"   ,
+  "slock-AF_ASH"   , "slock-AF_ECONET"   , "slock-AF_ATMSVC"   ,
+  "slock-AF_RDS"   , "slock-AF_SNA"      , "slock-AF_IRDA"     ,
+  "slock-AF_PPPOX" , "slock-AF_WANPIPE"  , "slock-AF_LLC"      ,
+  "slock-27"       , "slock-28"          , "slock-AF_CAN"      ,
+  "slock-AF_TIPC"  , "slock-AF_BLUETOOTH", "slock-AF_IUCV"     ,
+  "slock-AF_RXRPC" , "slock-AF_ISDN"     , "slock-AF_PHONET"   ,
+  "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG"      ,
+  "slock-AF_NFC"   , "slock-AF_VSOCK"    ,"slock-AF_MAX"
+};
+static const char *const af_family_clock_key_strings[AF_MAX+1] = {
+  "clock-AF_UNSPEC", "clock-AF_UNIX"     , "clock-AF_INET"     ,
+  "clock-AF_AX25"  , "clock-AF_IPX"      , "clock-AF_APPLETALK",
+  "clock-AF_NETROM", "clock-AF_BRIDGE"   , "clock-AF_ATMPVC"   ,
+  "clock-AF_X25"   , "clock-AF_INET6"    , "clock-AF_ROSE"     ,
+  "clock-AF_DECnet", "clock-AF_NETBEUI"  , "clock-AF_SECURITY" ,
+  "clock-AF_KEY"   , "clock-AF_NETLINK"  , "clock-AF_PACKET"   ,
+  "clock-AF_ASH"   , "clock-AF_ECONET"   , "clock-AF_ATMSVC"   ,
+  "clock-AF_RDS"   , "clock-AF_SNA"      , "clock-AF_IRDA"     ,
+  "clock-AF_PPPOX" , "clock-AF_WANPIPE"  , "clock-AF_LLC"      ,
+  "clock-27"       , "clock-28"          , "clock-AF_CAN"      ,
+  "clock-AF_TIPC"  , "clock-AF_BLUETOOTH", "clock-AF_IUCV"     ,
+  "clock-AF_RXRPC" , "clock-AF_ISDN"     , "clock-AF_PHONET"   ,
+  "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG"      ,
+  "clock-AF_NFC"   , "clock-AF_VSOCK"    , "clock-AF_MAX"
+};
+
+/*
+ * sk_callback_lock locking rules are per-address-family,
+ * so split the lock classes by using a per-AF key:
+ */
+static struct lock_class_key af_callback_keys[AF_MAX];
+
+/* Take into consideration the size of the struct sk_buff overhead in the
+ * determination of these values, since that is non-constant across
+ * platforms.  This makes socket queueing behavior and performance
+ * not depend upon such differences.
+ */
+#define _SK_MEM_PACKETS		256
+#define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
+#define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
+#define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
+
+/* Run time adjustable parameters. */
+__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
+EXPORT_SYMBOL(sysctl_wmem_max);
+__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
+EXPORT_SYMBOL(sysctl_rmem_max);
+__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
+__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
+
+/* Maximal space eaten by iovec or ancillary data plus some space */
+int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
+EXPORT_SYMBOL(sysctl_optmem_max);
+
+int sysctl_tstamp_allow_data __read_mostly = 1;
+
+struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
+EXPORT_SYMBOL_GPL(memalloc_socks);
+
+/**
+ * sk_set_memalloc - sets %SOCK_MEMALLOC
+ * @sk: socket to set it on
+ *
+ * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
+ * It's the responsibility of the admin to adjust min_free_kbytes
+ * to meet the requirements
+ */
+void sk_set_memalloc(struct sock *sk)
+{
+	sock_set_flag(sk, SOCK_MEMALLOC);
+	sk->sk_allocation |= __GFP_MEMALLOC;
+	static_key_slow_inc(&memalloc_socks);
+}
+EXPORT_SYMBOL_GPL(sk_set_memalloc);
+
+void sk_clear_memalloc(struct sock *sk)
+{
+	sock_reset_flag(sk, SOCK_MEMALLOC);
+	sk->sk_allocation &= ~__GFP_MEMALLOC;
+	static_key_slow_dec(&memalloc_socks);
+
+	/*
+	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
+	 * progress of swapping. SOCK_MEMALLOC may be cleared while
+	 * it has rmem allocations due to the last swapfile being deactivated
+	 * but there is a risk that the socket is unusable due to exceeding
+	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
+	 */
+	sk_mem_reclaim(sk);
+}
+EXPORT_SYMBOL_GPL(sk_clear_memalloc);
+
+int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
+{
+	int ret;
+	unsigned long pflags = current->flags;
+
+	/* these should have been dropped before queueing */
+	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
+
+	current->flags |= PF_MEMALLOC;
+	ret = sk->sk_backlog_rcv(sk, skb);
+	tsk_restore_flags(current, pflags, PF_MEMALLOC);
+
+	return ret;
+}
+EXPORT_SYMBOL(__sk_backlog_rcv);
+
+static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
+{
+	struct timeval tv;
+
+	if (optlen < sizeof(tv))
+		return -EINVAL;
+	if (copy_from_user(&tv, optval, sizeof(tv)))
+		return -EFAULT;
+	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
+		return -EDOM;
+
+	if (tv.tv_sec < 0) {
+		static int warned __read_mostly;
+
+		*timeo_p = 0;
+		if (warned < 10 && net_ratelimit()) {
+			warned++;
+			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
+				__func__, current->comm, task_pid_nr(current));
+		}
+		return 0;
+	}
+	*timeo_p = MAX_SCHEDULE_TIMEOUT;
+	if (tv.tv_sec == 0 && tv.tv_usec == 0)
+		return 0;
+	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
+		*timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
+	return 0;
+}
+
+static void sock_warn_obsolete_bsdism(const char *name)
+{
+	static int warned;
+	static char warncomm[TASK_COMM_LEN];
+	if (strcmp(warncomm, current->comm) && warned < 5) {
+		strcpy(warncomm,  current->comm);
+		pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
+			warncomm, name);
+		warned++;
+	}
+}
+
+#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
+
+static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
+{
+	if (sk->sk_flags & flags) {
+		sk->sk_flags &= ~flags;
+		if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP))
+			net_disable_timestamp();
+	}
+}
+
+
+int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
+{
+	int err;
+	unsigned long flags;
+	struct sk_buff_head *list = &sk->sk_receive_queue;
+
+	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
+		atomic_inc(&sk->sk_drops);
+		trace_sock_rcvqueue_full(sk, skb);
+		return -ENOMEM;
+	}
+
+	err = sk_filter(sk, skb);
+	if (err)
+		return err;
+
+	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
+		atomic_inc(&sk->sk_drops);
+		return -ENOBUFS;
+	}
+
+	skb->dev = NULL;
+	skb_set_owner_r(skb, sk);
+
+	/* we escape from rcu protected region, make sure we dont leak
+	 * a norefcounted dst
+	 */
+	skb_dst_force(skb);
+
+	spin_lock_irqsave(&list->lock, flags);
+	sock_skb_set_dropcount(sk, skb);
+	__skb_queue_tail(list, skb);
+	spin_unlock_irqrestore(&list->lock, flags);
+
+	if (!sock_flag(sk, SOCK_DEAD))
+		sk->sk_data_ready(sk);
+	return 0;
+}
+EXPORT_SYMBOL(sock_queue_rcv_skb);
+
+int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
+{
+	int rc = NET_RX_SUCCESS;
+
+	if (sk_filter(sk, skb))
+		goto discard_and_relse;
+
+	skb->dev = NULL;
+
+	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
+		atomic_inc(&sk->sk_drops);
+		goto discard_and_relse;
+	}
+	if (nested)
+		bh_lock_sock_nested(sk);
+	else
+		bh_lock_sock(sk);
+	if (!sock_owned_by_user(sk)) {
+		/*
+		 * trylock + unlock semantics:
+		 */
+		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
+
+		rc = sk_backlog_rcv(sk, skb);
+
+		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
+	} else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
+		bh_unlock_sock(sk);
+		atomic_inc(&sk->sk_drops);
+		goto discard_and_relse;
+	}
+
+	bh_unlock_sock(sk);
+out:
+	sock_put(sk);
+	return rc;
+discard_and_relse:
+	kfree_skb(skb);
+	goto out;
+}
+EXPORT_SYMBOL(sk_receive_skb);
+
+struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
+{
+	struct dst_entry *dst = __sk_dst_get(sk);
+
+	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
+		sk_tx_queue_clear(sk);
+		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
+		dst_release(dst);
+		return NULL;
+	}
+
+	return dst;
+}
+EXPORT_SYMBOL(__sk_dst_check);
+
+struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
+{
+	struct dst_entry *dst = sk_dst_get(sk);
+
+	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
+		sk_dst_reset(sk);
+		dst_release(dst);
+		return NULL;
+	}
+
+	return dst;
+}
+EXPORT_SYMBOL(sk_dst_check);
+
+static int sock_setbindtodevice(struct sock *sk, char __user *optval,
+				int optlen)
+{
+	int ret = -ENOPROTOOPT;
+#ifdef CONFIG_NETDEVICES
+	struct net *net = sock_net(sk);
+	char devname[IFNAMSIZ];
+	int index;
+
+	/* Sorry... */
+	ret = -EPERM;
+	if (!ns_capable(net->user_ns, CAP_NET_RAW))
+		goto out;
+
+	ret = -EINVAL;
+	if (optlen < 0)
+		goto out;
+
+	/* Bind this socket to a particular device like "eth0",
+	 * as specified in the passed interface name. If the
+	 * name is "" or the option length is zero the socket
+	 * is not bound.
+	 */
+	if (optlen > IFNAMSIZ - 1)
+		optlen = IFNAMSIZ - 1;
+	memset(devname, 0, sizeof(devname));
+
+	ret = -EFAULT;
+	if (copy_from_user(devname, optval, optlen))
+		goto out;
+
+	index = 0;
+	if (devname[0] != '\0') {
+		struct net_device *dev;
+
+		rcu_read_lock();
+		dev = dev_get_by_name_rcu(net, devname);
+		if (dev)
+			index = dev->ifindex;
+		rcu_read_unlock();
+		ret = -ENODEV;
+		if (!dev)
+			goto out;
+	}
+
+	lock_sock(sk);
+	sk->sk_bound_dev_if = index;
+	sk_dst_reset(sk);
+	release_sock(sk);
+
+	ret = 0;
+
+out:
+#endif
+
+	return ret;
+}
+
+static int sock_getbindtodevice(struct sock *sk, char __user *optval,
+				int __user *optlen, int len)
+{
+	int ret = -ENOPROTOOPT;
+#ifdef CONFIG_NETDEVICES
+	struct net *net = sock_net(sk);
+	char devname[IFNAMSIZ];
+
+	if (sk->sk_bound_dev_if == 0) {
+		len = 0;
+		goto zero;
+	}
+
+	ret = -EINVAL;
+	if (len < IFNAMSIZ)
+		goto out;
+
+	ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
+	if (ret)
+		goto out;
+
+	len = strlen(devname) + 1;
+
+	ret = -EFAULT;
+	if (copy_to_user(optval, devname, len))
+		goto out;
+
+zero:
+	ret = -EFAULT;
+	if (put_user(len, optlen))
+		goto out;
+
+	ret = 0;
+
+out:
+#endif
+
+	return ret;
+}
+
+static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
+{
+	if (valbool)
+		sock_set_flag(sk, bit);
+	else
+		sock_reset_flag(sk, bit);
+}
+
+bool sk_mc_loop(struct sock *sk)
+{
+	if (dev_recursion_level())
+		return false;
+	if (!sk)
+		return true;
+	switch (sk->sk_family) {
+	case AF_INET:
+		return inet_sk(sk)->mc_loop;
+#if IS_ENABLED(CONFIG_IPV6)
+	case AF_INET6:
+		return inet6_sk(sk)->mc_loop;
+#endif
+	}
+	WARN_ON(1);
+	return true;
+}
+EXPORT_SYMBOL(sk_mc_loop);
+
+/*
+ *	This is meant for all protocols to use and covers goings on
+ *	at the socket level. Everything here is generic.
+ */
+
+int sock_setsockopt(struct socket *sock, int level, int optname,
+		    char __user *optval, unsigned int optlen)
+{
+	struct sock *sk = sock->sk;
+	int val;
+	int valbool;
+	struct linger ling;
+	int ret = 0;
+
+	/*
+	 *	Options without arguments
+	 */
+
+	if (optname == SO_BINDTODEVICE)
+		return sock_setbindtodevice(sk, optval, optlen);
+
+	if (optlen < sizeof(int))
+		return -EINVAL;
+
+	if (get_user(val, (int __user *)optval))
+		return -EFAULT;
+
+	valbool = val ? 1 : 0;
+
+	lock_sock(sk);
+
+	switch (optname) {
+	case SO_DEBUG:
+		if (val && !capable(CAP_NET_ADMIN))
+			ret = -EACCES;
+		else
+			sock_valbool_flag(sk, SOCK_DBG, valbool);
+		break;
+	case SO_REUSEADDR:
+		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
+		break;
+	case SO_REUSEPORT:
+		sk->sk_reuseport = valbool;
+		break;
+	case SO_TYPE:
+	case SO_PROTOCOL:
+	case SO_DOMAIN:
+	case SO_ERROR:
+		ret = -ENOPROTOOPT;
+		break;
+	case SO_DONTROUTE:
+		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
+		break;
+	case SO_BROADCAST:
+		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
+		break;
+	case SO_SNDBUF:
+		/* Don't error on this BSD doesn't and if you think
+		 * about it this is right. Otherwise apps have to
+		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
+		 * are treated in BSD as hints
+		 */
+		val = min_t(u32, val, sysctl_wmem_max);
+set_sndbuf:
+		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
+		sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
+		/* Wake up sending tasks if we upped the value. */
+		sk->sk_write_space(sk);
+		break;
+
+	case SO_SNDBUFFORCE:
+		if (!capable(CAP_NET_ADMIN)) {
+			ret = -EPERM;
+			break;
+		}
+		goto set_sndbuf;
+
+	case SO_RCVBUF:
+		/* Don't error on this BSD doesn't and if you think
+		 * about it this is right. Otherwise apps have to
+		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
+		 * are treated in BSD as hints
+		 */
+		val = min_t(u32, val, sysctl_rmem_max);
+set_rcvbuf:
+		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
+		/*
+		 * We double it on the way in to account for
+		 * "struct sk_buff" etc. overhead.   Applications
+		 * assume that the SO_RCVBUF setting they make will
+		 * allow that much actual data to be received on that
+		 * socket.
+		 *
+		 * Applications are unaware that "struct sk_buff" and
+		 * other overheads allocate from the receive buffer
+		 * during socket buffer allocation.
+		 *
+		 * And after considering the possible alternatives,
+		 * returning the value we actually used in getsockopt
+		 * is the most desirable behavior.
+		 */
+		sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
+		break;
+
+	case SO_RCVBUFFORCE:
+		if (!capable(CAP_NET_ADMIN)) {
+			ret = -EPERM;
+			break;
+		}
+		goto set_rcvbuf;
+
+	case SO_KEEPALIVE:
+#ifdef CONFIG_INET
+		if (sk->sk_protocol == IPPROTO_TCP &&
+		    sk->sk_type == SOCK_STREAM)
+			tcp_set_keepalive(sk, valbool);
+#endif
+		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
+		break;
+
+	case SO_OOBINLINE:
+		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
+		break;
+
+	case SO_NO_CHECK:
+		sk->sk_no_check_tx = valbool;
+		break;
+
+	case SO_PRIORITY:
+		if ((val >= 0 && val <= 6) ||
+		    ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
+			sk->sk_priority = val;
+		else
+			ret = -EPERM;
+		break;
+
+	case SO_LINGER:
+		if (optlen < sizeof(ling)) {
+			ret = -EINVAL;	/* 1003.1g */
+			break;
+		}
+		if (copy_from_user(&ling, optval, sizeof(ling))) {
+			ret = -EFAULT;
+			break;
+		}
+		if (!ling.l_onoff)
+			sock_reset_flag(sk, SOCK_LINGER);
+		else {
+#if (BITS_PER_LONG == 32)
+			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
+				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
+			else
+#endif
+				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
+			sock_set_flag(sk, SOCK_LINGER);
+		}
+		break;
+
+	case SO_BSDCOMPAT:
+		sock_warn_obsolete_bsdism("setsockopt");
+		break;
+
+	case SO_PASSCRED:
+		if (valbool)
+			set_bit(SOCK_PASSCRED, &sock->flags);
+		else
+			clear_bit(SOCK_PASSCRED, &sock->flags);
+		break;
+
+	case SO_TIMESTAMP:
+	case SO_TIMESTAMPNS:
+		if (valbool)  {
+			if (optname == SO_TIMESTAMP)
+				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
+			else
+				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
+			sock_set_flag(sk, SOCK_RCVTSTAMP);
+			sock_enable_timestamp(sk, SOCK_TIMESTAMP);
+		} else {
+			sock_reset_flag(sk, SOCK_RCVTSTAMP);
+			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
+		}
+		break;
+
+	case SO_TIMESTAMPING:
+		if (val & ~SOF_TIMESTAMPING_MASK) {
+			ret = -EINVAL;
+			break;
+		}
+
+		if (val & SOF_TIMESTAMPING_OPT_ID &&
+		    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
+			if (sk->sk_protocol == IPPROTO_TCP) {
+				if (sk->sk_state != TCP_ESTABLISHED) {
+					ret = -EINVAL;
+					break;
+				}
+				sk->sk_tskey = tcp_sk(sk)->snd_una;
+			} else {
+				sk->sk_tskey = 0;
+			}
+		}
+		sk->sk_tsflags = val;
+		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
+			sock_enable_timestamp(sk,
+					      SOCK_TIMESTAMPING_RX_SOFTWARE);
+		else
+			sock_disable_timestamp(sk,
+					       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
+		break;
+
+	case SO_RCVLOWAT:
+		if (val < 0)
+			val = INT_MAX;
+		sk->sk_rcvlowat = val ? : 1;
+		break;
+
+	case SO_RCVTIMEO:
+		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
+		break;
+
+	case SO_SNDTIMEO:
+		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
+		break;
+
+	case SO_ATTACH_FILTER:
+		ret = -EINVAL;
+		if (optlen == sizeof(struct sock_fprog)) {
+			struct sock_fprog fprog;
+
+			ret = -EFAULT;
+			if (copy_from_user(&fprog, optval, sizeof(fprog)))
+				break;
+
+			ret = sk_attach_filter(&fprog, sk);
+		}
+		break;
+
+	case SO_ATTACH_BPF:
+		ret = -EINVAL;
+		if (optlen == sizeof(u32)) {
+			u32 ufd;
+
+			ret = -EFAULT;
+			if (copy_from_user(&ufd, optval, sizeof(ufd)))
+				break;
+
+			ret = sk_attach_bpf(ufd, sk);
+		}
+		break;
+
+	case SO_DETACH_FILTER:
+		ret = sk_detach_filter(sk);
+		break;
+
+	case SO_LOCK_FILTER:
+		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
+			ret = -EPERM;
+		else
+			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
+		break;
+
+	case SO_PASSSEC:
+		if (valbool)
+			set_bit(SOCK_PASSSEC, &sock->flags);
+		else
+			clear_bit(SOCK_PASSSEC, &sock->flags);
+		break;
+	case SO_MARK:
+		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
+			ret = -EPERM;
+		else
+			sk->sk_mark = val;
+		break;
+
+	case SO_RXQ_OVFL:
+		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
+		break;
+
+	case SO_WIFI_STATUS:
+		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
+		break;
+
+	case SO_PEEK_OFF:
+		if (sock->ops->set_peek_off)
+			ret = sock->ops->set_peek_off(sk, val);
+		else
+			ret = -EOPNOTSUPP;
+		break;
+
+	case SO_NOFCS:
+		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
+		break;
+
+	case SO_SELECT_ERR_QUEUE:
+		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
+		break;
+
+#ifdef CONFIG_NET_RX_BUSY_POLL
+	case SO_BUSY_POLL:
+		/* allow unprivileged users to decrease the value */
+		if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
+			ret = -EPERM;
+		else {
+			if (val < 0)
+				ret = -EINVAL;
+			else
+				sk->sk_ll_usec = val;
+		}
+		break;
+#endif
+
+	case SO_MAX_PACING_RATE:
+		sk->sk_max_pacing_rate = val;
+		sk->sk_pacing_rate = min(sk->sk_pacing_rate,
+					 sk->sk_max_pacing_rate);
+		break;
+
+	default:
+		ret = -ENOPROTOOPT;
+		break;
+	}
+	release_sock(sk);
+	return ret;
+}
+EXPORT_SYMBOL(sock_setsockopt);
+
+
+static void cred_to_ucred(struct pid *pid, const struct cred *cred,
+			  struct ucred *ucred)
+{
+	ucred->pid = pid_vnr(pid);
+	ucred->uid = ucred->gid = -1;
+	if (cred) {
+		struct user_namespace *current_ns = current_user_ns();
+
+		ucred->uid = from_kuid_munged(current_ns, cred->euid);
+		ucred->gid = from_kgid_munged(current_ns, cred->egid);
+	}
+}
+
+int sock_getsockopt(struct socket *sock, int level, int optname,
+		    char __user *optval, int __user *optlen)
+{
+	struct sock *sk = sock->sk;
+
+	union {
+		int val;
+		struct linger ling;
+		struct timeval tm;
+	} v;
+
+	int lv = sizeof(int);
+	int len;
+
+	if (get_user(len, optlen))
+		return -EFAULT;
+	if (len < 0)
+		return -EINVAL;
+
+	memset(&v, 0, sizeof(v));
+
+	switch (optname) {
+	case SO_DEBUG:
+		v.val = sock_flag(sk, SOCK_DBG);
+		break;
+
+	case SO_DONTROUTE:
+		v.val = sock_flag(sk, SOCK_LOCALROUTE);
+		break;
+
+	case SO_BROADCAST:
+		v.val = sock_flag(sk, SOCK_BROADCAST);
+		break;
+
+	case SO_SNDBUF:
+		v.val = sk->sk_sndbuf;
+		break;
+
+	case SO_RCVBUF:
+		v.val = sk->sk_rcvbuf;
+		break;
+
+	case SO_REUSEADDR:
+		v.val = sk->sk_reuse;
+		break;
+
+	case SO_REUSEPORT:
+		v.val = sk->sk_reuseport;
+		break;
+
+	case SO_KEEPALIVE:
+		v.val = sock_flag(sk, SOCK_KEEPOPEN);
+		break;
+
+	case SO_TYPE:
+		v.val = sk->sk_type;
+		break;
+
+	case SO_PROTOCOL:
+		v.val = sk->sk_protocol;
+		break;
+
+	case SO_DOMAIN:
+		v.val = sk->sk_family;
+		break;
+
+	case SO_ERROR:
+		v.val = -sock_error(sk);
+		if (v.val == 0)
+			v.val = xchg(&sk->sk_err_soft, 0);
+		break;
+
+	case SO_OOBINLINE:
+		v.val = sock_flag(sk, SOCK_URGINLINE);
+		break;
+
+	case SO_NO_CHECK:
+		v.val = sk->sk_no_check_tx;
+		break;
+
+	case SO_PRIORITY:
+		v.val = sk->sk_priority;
+		break;
+
+	case SO_LINGER:
+		lv		= sizeof(v.ling);
+		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
+		v.ling.l_linger	= sk->sk_lingertime / HZ;
+		break;
+
+	case SO_BSDCOMPAT:
+		sock_warn_obsolete_bsdism("getsockopt");
+		break;
+
+	case SO_TIMESTAMP:
+		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
+				!sock_flag(sk, SOCK_RCVTSTAMPNS);
+		break;
+
+	case SO_TIMESTAMPNS:
+		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
+		break;
+
+	case SO_TIMESTAMPING:
+		v.val = sk->sk_tsflags;
+		break;
+
+	case SO_RCVTIMEO:
+		lv = sizeof(struct timeval);
+		if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
+			v.tm.tv_sec = 0;
+			v.tm.tv_usec = 0;
+		} else {
+			v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
+			v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
+		}
+		break;
+
+	case SO_SNDTIMEO:
+		lv = sizeof(struct timeval);
+		if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
+			v.tm.tv_sec = 0;
+			v.tm.tv_usec = 0;
+		} else {
+			v.tm.tv_sec = sk->sk_sndtimeo / HZ;
+			v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
+		}
+		break;
+
+	case SO_RCVLOWAT:
+		v.val = sk->sk_rcvlowat;
+		break;
+
+	case SO_SNDLOWAT:
+		v.val = 1;
+		break;
+
+	case SO_PASSCRED:
+		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
+		break;
+
+	case SO_PEERCRED:
+	{
+		struct ucred peercred;
+		if (len > sizeof(peercred))
+			len = sizeof(peercred);
+		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
+		if (copy_to_user(optval, &peercred, len))
+			return -EFAULT;
+		goto lenout;
+	}
+
+	case SO_PEERNAME:
+	{
+		char address[128];
+
+		if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
+			return -ENOTCONN;
+		if (lv < len)
+			return -EINVAL;
+		if (copy_to_user(optval, address, len))
+			return -EFAULT;
+		goto lenout;
+	}
+
+	/* Dubious BSD thing... Probably nobody even uses it, but
+	 * the UNIX standard wants it for whatever reason... -DaveM
+	 */
+	case SO_ACCEPTCONN:
+		v.val = sk->sk_state == TCP_LISTEN;
+		break;
+
+	case SO_PASSSEC:
+		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
+		break;
+
+	case SO_PEERSEC:
+		return security_socket_getpeersec_stream(sock, optval, optlen, len);
+
+	case SO_MARK:
+		v.val = sk->sk_mark;
+		break;
+
+	case SO_RXQ_OVFL:
+		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
+		break;
+
+	case SO_WIFI_STATUS:
+		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
+		break;
+
+	case SO_PEEK_OFF:
+		if (!sock->ops->set_peek_off)
+			return -EOPNOTSUPP;
+
+		v.val = sk->sk_peek_off;
+		break;
+	case SO_NOFCS:
+		v.val = sock_flag(sk, SOCK_NOFCS);
+		break;
+
+	case SO_BINDTODEVICE:
+		return sock_getbindtodevice(sk, optval, optlen, len);
+
+	case SO_GET_FILTER:
+		len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
+		if (len < 0)
+			return len;
+
+		goto lenout;
+
+	case SO_LOCK_FILTER:
+		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
+		break;
+
+	case SO_BPF_EXTENSIONS:
+		v.val = bpf_tell_extensions();
+		break;
+
+	case SO_SELECT_ERR_QUEUE:
+		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
+		break;
+
+#ifdef CONFIG_NET_RX_BUSY_POLL
+	case SO_BUSY_POLL:
+		v.val = sk->sk_ll_usec;
+		break;
+#endif
+
+	case SO_MAX_PACING_RATE:
+		v.val = sk->sk_max_pacing_rate;
+		break;
+
+	case SO_INCOMING_CPU:
+		v.val = sk->sk_incoming_cpu;
+		break;
+
+	default:
+		/* We implement the SO_SNDLOWAT etc to not be settable
+		 * (1003.1g 7).
+		 */
+		return -ENOPROTOOPT;
+	}
+
+	if (len > lv)
+		len = lv;
+	if (copy_to_user(optval, &v, len))
+		return -EFAULT;
+lenout:
+	if (put_user(len, optlen))
+		return -EFAULT;
+	return 0;
+}
+
+/*
+ * Initialize an sk_lock.
+ *
+ * (We also register the sk_lock with the lock validator.)
+ */
+static inline void sock_lock_init(struct sock *sk)
+{
+	sock_lock_init_class_and_name(sk,
+			af_family_slock_key_strings[sk->sk_family],
+			af_family_slock_keys + sk->sk_family,
+			af_family_key_strings[sk->sk_family],
+			af_family_keys + sk->sk_family);
+}
+
+/*
+ * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
+ * even temporarly, because of RCU lookups. sk_node should also be left as is.
+ * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
+ */
+static void sock_copy(struct sock *nsk, const struct sock *osk)
+{
+#ifdef CONFIG_SECURITY_NETWORK
+	void *sptr = nsk->sk_security;
+#endif
+	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
+
+	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
+	       osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
+
+#ifdef CONFIG_SECURITY_NETWORK
+	nsk->sk_security = sptr;
+	security_sk_clone(osk, nsk);
+#endif
+}
+
+void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
+{
+	unsigned long nulls1, nulls2;
+
+	nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
+	nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
+	if (nulls1 > nulls2)
+		swap(nulls1, nulls2);
+
+	if (nulls1 != 0)
+		memset((char *)sk, 0, nulls1);
+	memset((char *)sk + nulls1 + sizeof(void *), 0,
+	       nulls2 - nulls1 - sizeof(void *));
+	memset((char *)sk + nulls2 + sizeof(void *), 0,
+	       size - nulls2 - sizeof(void *));
+}
+EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
+
+static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
+		int family)
+{
+	struct sock *sk;
+	struct kmem_cache *slab;
+
+	slab = prot->slab;
+	if (slab != NULL) {
+		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
+		if (!sk)
+			return sk;
+		if (priority & __GFP_ZERO) {
+			if (prot->clear_sk)
+				prot->clear_sk(sk, prot->obj_size);
+			else
+				sk_prot_clear_nulls(sk, prot->obj_size);
+		}
+	} else
+		sk = kmalloc(prot->obj_size, priority);
+
+	if (sk != NULL) {
+		kmemcheck_annotate_bitfield(sk, flags);
+
+		if (security_sk_alloc(sk, family, priority))
+			goto out_free;
+
+		if (!try_module_get(prot->owner))
+			goto out_free_sec;
+		sk_tx_queue_clear(sk);
+	}
+
+	return sk;
+
+out_free_sec:
+	security_sk_free(sk);
+out_free:
+	if (slab != NULL)
+		kmem_cache_free(slab, sk);
+	else
+		kfree(sk);
+	return NULL;
+}
+
+static void sk_prot_free(struct proto *prot, struct sock *sk)
+{
+	struct kmem_cache *slab;
+	struct module *owner;
+
+	owner = prot->owner;
+	slab = prot->slab;
+
+	security_sk_free(sk);
+	if (slab != NULL)
+		kmem_cache_free(slab, sk);
+	else
+		kfree(sk);
+	module_put(owner);
+}
+
+#if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
+void sock_update_netprioidx(struct sock *sk)
+{
+	if (in_interrupt())
+		return;
+
+	sk->sk_cgrp_prioidx = task_netprioidx(current);
+}
+EXPORT_SYMBOL_GPL(sock_update_netprioidx);
+#endif
+
+/**
+ *	sk_alloc - All socket objects are allocated here
+ *	@net: the applicable net namespace
+ *	@family: protocol family
+ *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
+ *	@prot: struct proto associated with this new sock instance
+ */
+struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
+		      struct proto *prot)
+{
+	struct sock *sk;
+
+	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
+	if (sk) {
+		sk->sk_family = family;
+		/*
+		 * See comment in struct sock definition to understand
+		 * why we need sk_prot_creator -acme
+		 */
+		sk->sk_prot = sk->sk_prot_creator = prot;
+		sock_lock_init(sk);
+		sock_net_set(sk, get_net(net));
+		atomic_set(&sk->sk_wmem_alloc, 1);
+
+		sock_update_classid(sk);
+		sock_update_netprioidx(sk);
+	}
+
+	return sk;
+}
+EXPORT_SYMBOL(sk_alloc);
+
+static void __sk_free(struct sock *sk)
+{
+	struct sk_filter *filter;
+
+	if (sk->sk_destruct)
+		sk->sk_destruct(sk);
+
+	filter = rcu_dereference_check(sk->sk_filter,
+				       atomic_read(&sk->sk_wmem_alloc) == 0);
+	if (filter) {
+		sk_filter_uncharge(sk, filter);
+		RCU_INIT_POINTER(sk->sk_filter, NULL);
+	}
+
+	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
+
+	if (atomic_read(&sk->sk_omem_alloc))
+		pr_debug("%s: optmem leakage (%d bytes) detected\n",
+			 __func__, atomic_read(&sk->sk_omem_alloc));
+
+	if (sk->sk_peer_cred)
+		put_cred(sk->sk_peer_cred);
+	put_pid(sk->sk_peer_pid);
+	put_net(sock_net(sk));
+	sk_prot_free(sk->sk_prot_creator, sk);
+}
+
+void sk_free(struct sock *sk)
+{
+	/*
+	 * We subtract one from sk_wmem_alloc and can know if
+	 * some packets are still in some tx queue.
+	 * If not null, sock_wfree() will call __sk_free(sk) later
+	 */
+	if (atomic_dec_and_test(&sk->sk_wmem_alloc))
+		__sk_free(sk);
+}
+EXPORT_SYMBOL(sk_free);
+
+/*
+ * Last sock_put should drop reference to sk->sk_net. It has already
+ * been dropped in sk_change_net. Taking reference to stopping namespace
+ * is not an option.
+ * Take reference to a socket to remove it from hash _alive_ and after that
+ * destroy it in the context of init_net.
+ */
+void sk_release_kernel(struct sock *sk)
+{
+	if (sk == NULL || sk->sk_socket == NULL)
+		return;
+
+	sock_hold(sk);
+	sock_release(sk->sk_socket);
+	sock_net_set(sk, get_net(&init_net));
+	sock_put(sk);
+}
+EXPORT_SYMBOL(sk_release_kernel);
+
+static void sk_update_clone(const struct sock *sk, struct sock *newsk)
+{
+	if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
+		sock_update_memcg(newsk);
+}
+
+/**
+ *	sk_clone_lock - clone a socket, and lock its clone
+ *	@sk: the socket to clone
+ *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
+ *
+ *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
+ */
+struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
+{
+	struct sock *newsk;
+	bool is_charged = true;
+
+	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
+	if (newsk != NULL) {
+		struct sk_filter *filter;
+
+		sock_copy(newsk, sk);
+
+		/* SANITY */
+		get_net(sock_net(newsk));
+		sk_node_init(&newsk->sk_node);
+		sock_lock_init(newsk);
+		bh_lock_sock(newsk);
+		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
+		newsk->sk_backlog.len = 0;
+
+		atomic_set(&newsk->sk_rmem_alloc, 0);
+		/*
+		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
+		 */
+		atomic_set(&newsk->sk_wmem_alloc, 1);
+		atomic_set(&newsk->sk_omem_alloc, 0);
+		skb_queue_head_init(&newsk->sk_receive_queue);
+		skb_queue_head_init(&newsk->sk_write_queue);
+
+		spin_lock_init(&newsk->sk_dst_lock);
+		rwlock_init(&newsk->sk_callback_lock);
+		lockdep_set_class_and_name(&newsk->sk_callback_lock,
+				af_callback_keys + newsk->sk_family,
+				af_family_clock_key_strings[newsk->sk_family]);
+
+		newsk->sk_dst_cache	= NULL;
+		newsk->sk_wmem_queued	= 0;
+		newsk->sk_forward_alloc = 0;
+		newsk->sk_send_head	= NULL;
+		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
+
+		sock_reset_flag(newsk, SOCK_DONE);
+		skb_queue_head_init(&newsk->sk_error_queue);
+
+		filter = rcu_dereference_protected(newsk->sk_filter, 1);
+		if (filter != NULL)
+			/* though it's an empty new sock, the charging may fail
+			 * if sysctl_optmem_max was changed between creation of
+			 * original socket and cloning
+			 */
+			is_charged = sk_filter_charge(newsk, filter);
+
+		if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk))) {
+			/* It is still raw copy of parent, so invalidate
+			 * destructor and make plain sk_free() */
+			newsk->sk_destruct = NULL;
+			bh_unlock_sock(newsk);
+			sk_free(newsk);
+			newsk = NULL;
+			goto out;
+		}
+
+		newsk->sk_err	   = 0;
+		newsk->sk_priority = 0;
+		newsk->sk_incoming_cpu = raw_smp_processor_id();
+		atomic64_set(&newsk->sk_cookie, 0);
+		/*
+		 * Before updating sk_refcnt, we must commit prior changes to memory
+		 * (Documentation/RCU/rculist_nulls.txt for details)
+		 */
+		smp_wmb();
+		atomic_set(&newsk->sk_refcnt, 2);
+
+		/*
+		 * Increment the counter in the same struct proto as the master
+		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
+		 * is the same as sk->sk_prot->socks, as this field was copied
+		 * with memcpy).
+		 *
+		 * This _changes_ the previous behaviour, where
+		 * tcp_create_openreq_child always was incrementing the
+		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
+		 * to be taken into account in all callers. -acme
+		 */
+		sk_refcnt_debug_inc(newsk);
+		sk_set_socket(newsk, NULL);
+		newsk->sk_wq = NULL;
+
+		sk_update_clone(sk, newsk);
+
+		if (newsk->sk_prot->sockets_allocated)
+			sk_sockets_allocated_inc(newsk);
+
+		if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
+			net_enable_timestamp();
+	}
+out:
+	return newsk;
+}
+EXPORT_SYMBOL_GPL(sk_clone_lock);
+
+void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
+{
+	__sk_dst_set(sk, dst);
+	sk->sk_route_caps = dst->dev->features;
+	if (sk->sk_route_caps & NETIF_F_GSO)
+		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
+	sk->sk_route_caps &= ~sk->sk_route_nocaps;
+	if (sk_can_gso(sk)) {
+		if (dst->header_len) {
+			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
+		} else {
+			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
+			sk->sk_gso_max_size = dst->dev->gso_max_size;
+			sk->sk_gso_max_segs = dst->dev->gso_max_segs;
+		}
+	}
+}
+EXPORT_SYMBOL_GPL(sk_setup_caps);
+
+/*
+ *	Simple resource managers for sockets.
+ */
+
+
+/*
+ * Write buffer destructor automatically called from kfree_skb.
+ */
+void sock_wfree(struct sk_buff *skb)
+{
+	struct sock *sk = skb->sk;
+	unsigned int len = skb->truesize;
+
+	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
+		/*
+		 * Keep a reference on sk_wmem_alloc, this will be released
+		 * after sk_write_space() call
+		 */
+		atomic_sub(len - 1, &sk->sk_wmem_alloc);
+		sk->sk_write_space(sk);
+		len = 1;
+	}
+	/*
+	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
+	 * could not do because of in-flight packets
+	 */
+	if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
+		__sk_free(sk);
+}
+EXPORT_SYMBOL(sock_wfree);
+
+void skb_orphan_partial(struct sk_buff *skb)
+{
+	/* TCP stack sets skb->ooo_okay based on sk_wmem_alloc,
+	 * so we do not completely orphan skb, but transfert all
+	 * accounted bytes but one, to avoid unexpected reorders.
+	 */
+	if (skb->destructor == sock_wfree
+#ifdef CONFIG_INET
+	    || skb->destructor == tcp_wfree
+#endif
+		) {
+		atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc);
+		skb->truesize = 1;
+	} else {
+		skb_orphan(skb);
+	}
+}
+EXPORT_SYMBOL(skb_orphan_partial);
+
+/*
+ * Read buffer destructor automatically called from kfree_skb.
+ */
+void sock_rfree(struct sk_buff *skb)
+{
+	struct sock *sk = skb->sk;
+	unsigned int len = skb->truesize;
+
+	atomic_sub(len, &sk->sk_rmem_alloc);
+	sk_mem_uncharge(sk, len);
+}
+EXPORT_SYMBOL(sock_rfree);
+
+/*
+ * Buffer destructor for skbs that are not used directly in read or write
+ * path, e.g. for error handler skbs. Automatically called from kfree_skb.
+ */
+void sock_efree(struct sk_buff *skb)
+{
+	sock_put(skb->sk);
+}
+EXPORT_SYMBOL(sock_efree);
+
+kuid_t sock_i_uid(struct sock *sk)
+{
+	kuid_t uid;
+
+	read_lock_bh(&sk->sk_callback_lock);
+	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
+	read_unlock_bh(&sk->sk_callback_lock);
+	return uid;
+}
+EXPORT_SYMBOL(sock_i_uid);
+
+unsigned long sock_i_ino(struct sock *sk)
+{
+	unsigned long ino;
+
+	read_lock_bh(&sk->sk_callback_lock);
+	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
+	read_unlock_bh(&sk->sk_callback_lock);
+	return ino;
+}
+EXPORT_SYMBOL(sock_i_ino);
+
+/*
+ * Allocate a skb from the socket's send buffer.
+ */
+struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
+			     gfp_t priority)
+{
+	if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
+		struct sk_buff *skb = alloc_skb(size, priority);
+		if (skb) {
+			skb_set_owner_w(skb, sk);
+			return skb;
+		}
+	}
+	return NULL;
+}
+EXPORT_SYMBOL(sock_wmalloc);
+
+/*
+ * Allocate a memory block from the socket's option memory buffer.
+ */
+void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
+{
+	if ((unsigned int)size <= sysctl_optmem_max &&
+	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
+		void *mem;
+		/* First do the add, to avoid the race if kmalloc
+		 * might sleep.
+		 */
+		atomic_add(size, &sk->sk_omem_alloc);
+		mem = kmalloc(size, priority);
+		if (mem)
+			return mem;
+		atomic_sub(size, &sk->sk_omem_alloc);
+	}
+	return NULL;
+}
+EXPORT_SYMBOL(sock_kmalloc);
+
+/* Free an option memory block. Note, we actually want the inline
+ * here as this allows gcc to detect the nullify and fold away the
+ * condition entirely.
+ */
+static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
+				  const bool nullify)
+{
+	if (WARN_ON_ONCE(!mem))
+		return;
+	if (nullify)
+		kzfree(mem);
+	else
+		kfree(mem);
+	atomic_sub(size, &sk->sk_omem_alloc);
+}
+
+void sock_kfree_s(struct sock *sk, void *mem, int size)
+{
+	__sock_kfree_s(sk, mem, size, false);
+}
+EXPORT_SYMBOL(sock_kfree_s);
+
+void sock_kzfree_s(struct sock *sk, void *mem, int size)
+{
+	__sock_kfree_s(sk, mem, size, true);
+}
+EXPORT_SYMBOL(sock_kzfree_s);
+
+/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
+   I think, these locks should be removed for datagram sockets.
+ */
+static long sock_wait_for_wmem(struct sock *sk, long timeo)
+{
+	DEFINE_WAIT(wait);
+
+	clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
+	for (;;) {
+		if (!timeo)
+			break;
+		if (signal_pending(current))
+			break;
+		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
+		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
+			break;
+		if (sk->sk_shutdown & SEND_SHUTDOWN)
+			break;
+		if (sk->sk_err)
+			break;
+		timeo = schedule_timeout(timeo);
+	}
+	finish_wait(sk_sleep(sk), &wait);
+	return timeo;
+}
+
+
+/*
+ *	Generic send/receive buffer handlers
+ */
+
+struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
+				     unsigned long data_len, int noblock,
+				     int *errcode, int max_page_order)
+{
+	struct sk_buff *skb;
+	long timeo;
+	int err;
+
+	timeo = sock_sndtimeo(sk, noblock);
+	for (;;) {
+		err = sock_error(sk);
+		if (err != 0)
+			goto failure;
+
+		err = -EPIPE;
+		if (sk->sk_shutdown & SEND_SHUTDOWN)
+			goto failure;
+
+		if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
+			break;
+
+		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
+		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
+		err = -EAGAIN;
+		if (!timeo)
+			goto failure;
+		if (signal_pending(current))
+			goto interrupted;
+		timeo = sock_wait_for_wmem(sk, timeo);
+	}
+	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
+				   errcode, sk->sk_allocation);
+	if (skb)
+		skb_set_owner_w(skb, sk);
+	return skb;
+
+interrupted:
+	err = sock_intr_errno(timeo);
+failure:
+	*errcode = err;
+	return NULL;
+}
+EXPORT_SYMBOL(sock_alloc_send_pskb);
+
+struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
+				    int noblock, int *errcode)
+{
+	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
+}
+EXPORT_SYMBOL(sock_alloc_send_skb);
+
+/* On 32bit arches, an skb frag is limited to 2^15 */
+#define SKB_FRAG_PAGE_ORDER	get_order(32768)
+
+/**
+ * skb_page_frag_refill - check that a page_frag contains enough room
+ * @sz: minimum size of the fragment we want to get
+ * @pfrag: pointer to page_frag
+ * @gfp: priority for memory allocation
+ *
+ * Note: While this allocator tries to use high order pages, there is
+ * no guarantee that allocations succeed. Therefore, @sz MUST be
+ * less or equal than PAGE_SIZE.
+ */
+bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
+{
+	if (pfrag->page) {
+		if (atomic_read(&pfrag->page->_count) == 1) {
+			pfrag->offset = 0;
+			return true;
+		}
+		if (pfrag->offset + sz <= pfrag->size)
+			return true;
+		put_page(pfrag->page);
+	}
+
+	pfrag->offset = 0;
+	if (SKB_FRAG_PAGE_ORDER) {
+		pfrag->page = alloc_pages((gfp & ~__GFP_WAIT) | __GFP_COMP |
+					  __GFP_NOWARN | __GFP_NORETRY,
+					  SKB_FRAG_PAGE_ORDER);
+		if (likely(pfrag->page)) {
+			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
+			return true;
+		}
+	}
+	pfrag->page = alloc_page(gfp);
+	if (likely(pfrag->page)) {
+		pfrag->size = PAGE_SIZE;
+		return true;
+	}
+	return false;
+}
+EXPORT_SYMBOL(skb_page_frag_refill);
+
+bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
+{
+	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
+		return true;
+
+	sk_enter_memory_pressure(sk);
+	sk_stream_moderate_sndbuf(sk);
+	return false;
+}
+EXPORT_SYMBOL(sk_page_frag_refill);
+
+static void __lock_sock(struct sock *sk)
+	__releases(&sk->sk_lock.slock)
+	__acquires(&sk->sk_lock.slock)
+{
+	DEFINE_WAIT(wait);
+
+	for (;;) {
+		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
+					TASK_UNINTERRUPTIBLE);
+		spin_unlock_bh(&sk->sk_lock.slock);
+		schedule();
+		spin_lock_bh(&sk->sk_lock.slock);
+		if (!sock_owned_by_user(sk))
+			break;
+	}
+	finish_wait(&sk->sk_lock.wq, &wait);
+}
+
+static void __release_sock(struct sock *sk)
+	__releases(&sk->sk_lock.slock)
+	__acquires(&sk->sk_lock.slock)
+{
+	struct sk_buff *skb = sk->sk_backlog.head;
+
+	do {
+		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
+		bh_unlock_sock(sk);
+
+		do {
+			struct sk_buff *next = skb->next;
+
+			prefetch(next);
+			WARN_ON_ONCE(skb_dst_is_noref(skb));
+			skb->next = NULL;
+			sk_backlog_rcv(sk, skb);
+
+			/*
+			 * We are in process context here with softirqs
+			 * disabled, use cond_resched_softirq() to preempt.
+			 * This is safe to do because we've taken the backlog
+			 * queue private:
+			 */
+			cond_resched_softirq();
+
+			skb = next;
+		} while (skb != NULL);
+
+		bh_lock_sock(sk);
+	} while ((skb = sk->sk_backlog.head) != NULL);
+
+	/*
+	 * Doing the zeroing here guarantee we can not loop forever
+	 * while a wild producer attempts to flood us.
+	 */
+	sk->sk_backlog.len = 0;
+}
+
+/**
+ * sk_wait_data - wait for data to arrive at sk_receive_queue
+ * @sk:    sock to wait on
+ * @timeo: for how long
+ *
+ * Now socket state including sk->sk_err is changed only under lock,
+ * hence we may omit checks after joining wait queue.
+ * We check receive queue before schedule() only as optimization;
+ * it is very likely that release_sock() added new data.
+ */
+int sk_wait_data(struct sock *sk, long *timeo)
+{
+	int rc;
+	DEFINE_WAIT(wait);
+
+	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+	set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
+	rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
+	clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
+	finish_wait(sk_sleep(sk), &wait);
+	return rc;
+}
+EXPORT_SYMBOL(sk_wait_data);
+
+/**
+ *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
+ *	@sk: socket
+ *	@size: memory size to allocate
+ *	@kind: allocation type
+ *
+ *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
+ *	rmem allocation. This function assumes that protocols which have
+ *	memory_pressure use sk_wmem_queued as write buffer accounting.
+ */
+int __sk_mem_schedule(struct sock *sk, int size, int kind)
+{
+	struct proto *prot = sk->sk_prot;
+	int amt = sk_mem_pages(size);
+	long allocated;
+	int parent_status = UNDER_LIMIT;
+
+	sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
+
+	allocated = sk_memory_allocated_add(sk, amt, &parent_status);
+
+	/* Under limit. */
+	if (parent_status == UNDER_LIMIT &&
+			allocated <= sk_prot_mem_limits(sk, 0)) {
+		sk_leave_memory_pressure(sk);
+		return 1;
+	}
+
+	/* Under pressure. (we or our parents) */
+	if ((parent_status > SOFT_LIMIT) ||
+			allocated > sk_prot_mem_limits(sk, 1))
+		sk_enter_memory_pressure(sk);
+
+	/* Over hard limit (we or our parents) */
+	if ((parent_status == OVER_LIMIT) ||
+			(allocated > sk_prot_mem_limits(sk, 2)))
+		goto suppress_allocation;
+
+	/* guarantee minimum buffer size under pressure */
+	if (kind == SK_MEM_RECV) {
+		if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
+			return 1;
+
+	} else { /* SK_MEM_SEND */
+		if (sk->sk_type == SOCK_STREAM) {
+			if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
+				return 1;
+		} else if (atomic_read(&sk->sk_wmem_alloc) <
+			   prot->sysctl_wmem[0])
+				return 1;
+	}
+
+	if (sk_has_memory_pressure(sk)) {
+		int alloc;
+
+		if (!sk_under_memory_pressure(sk))
+			return 1;
+		alloc = sk_sockets_allocated_read_positive(sk);
+		if (sk_prot_mem_limits(sk, 2) > alloc *
+		    sk_mem_pages(sk->sk_wmem_queued +
+				 atomic_read(&sk->sk_rmem_alloc) +
+				 sk->sk_forward_alloc))
+			return 1;
+	}
+
+suppress_allocation:
+
+	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
+		sk_stream_moderate_sndbuf(sk);
+
+		/* Fail only if socket is _under_ its sndbuf.
+		 * In this case we cannot block, so that we have to fail.
+		 */
+		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
+			return 1;
+	}
+
+	trace_sock_exceed_buf_limit(sk, prot, allocated);
+
+	/* Alas. Undo changes. */
+	sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
+
+	sk_memory_allocated_sub(sk, amt);
+
+	return 0;
+}
+EXPORT_SYMBOL(__sk_mem_schedule);
+
+/**
+ *	__sk_reclaim - reclaim memory_allocated
+ *	@sk: socket
+ */
+void __sk_mem_reclaim(struct sock *sk)
+{
+	sk_memory_allocated_sub(sk,
+				sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT);
+	sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
+
+	if (sk_under_memory_pressure(sk) &&
+	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
+		sk_leave_memory_pressure(sk);
+}
+EXPORT_SYMBOL(__sk_mem_reclaim);
+
+
+/*
+ * Set of default routines for initialising struct proto_ops when
+ * the protocol does not support a particular function. In certain
+ * cases where it makes no sense for a protocol to have a "do nothing"
+ * function, some default processing is provided.
+ */
+
+int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
+{
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(sock_no_bind);
+
+int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
+		    int len, int flags)
+{
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(sock_no_connect);
+
+int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
+{
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(sock_no_socketpair);
+
+int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
+{
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(sock_no_accept);
+
+int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
+		    int *len, int peer)
+{
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(sock_no_getname);
+
+unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
+{
+	return 0;
+}
+EXPORT_SYMBOL(sock_no_poll);
+
+int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(sock_no_ioctl);
+
+int sock_no_listen(struct socket *sock, int backlog)
+{
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(sock_no_listen);
+
+int sock_no_shutdown(struct socket *sock, int how)
+{
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(sock_no_shutdown);
+
+int sock_no_setsockopt(struct socket *sock, int level, int optname,
+		    char __user *optval, unsigned int optlen)
+{
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(sock_no_setsockopt);
+
+int sock_no_getsockopt(struct socket *sock, int level, int optname,
+		    char __user *optval, int __user *optlen)
+{
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(sock_no_getsockopt);
+
+int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
+{
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(sock_no_sendmsg);
+
+int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
+		    int flags)
+{
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(sock_no_recvmsg);
+
+int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
+{
+	/* Mirror missing mmap method error code */
+	return -ENODEV;
+}
+EXPORT_SYMBOL(sock_no_mmap);
+
+ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
+{
+	ssize_t res;
+	struct msghdr msg = {.msg_flags = flags};
+	struct kvec iov;
+	char *kaddr = kmap(page);
+	iov.iov_base = kaddr + offset;
+	iov.iov_len = size;
+	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
+	kunmap(page);
+	return res;
+}
+EXPORT_SYMBOL(sock_no_sendpage);
+
+/*
+ *	Default Socket Callbacks
+ */
+
+static void sock_def_wakeup(struct sock *sk)
+{
+	struct socket_wq *wq;
+
+	rcu_read_lock();
+	wq = rcu_dereference(sk->sk_wq);
+	if (wq_has_sleeper(wq))
+		wake_up_interruptible_all(&wq->wait);
+	rcu_read_unlock();
+}
+
+static void sock_def_error_report(struct sock *sk)
+{
+	struct socket_wq *wq;
+
+	rcu_read_lock();
+	wq = rcu_dereference(sk->sk_wq);
+	if (wq_has_sleeper(wq))
+		wake_up_interruptible_poll(&wq->wait, POLLERR);
+	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
+	rcu_read_unlock();
+}
+
+static void sock_def_readable(struct sock *sk)
+{
+	struct socket_wq *wq;
+
+	rcu_read_lock();
+	wq = rcu_dereference(sk->sk_wq);
+	if (wq_has_sleeper(wq))
+		wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
+						POLLRDNORM | POLLRDBAND);
+	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
+	rcu_read_unlock();
+}
+
+static void sock_def_write_space(struct sock *sk)
+{
+	struct socket_wq *wq;
+
+	rcu_read_lock();
+
+	/* Do not wake up a writer until he can make "significant"
+	 * progress.  --DaveM
+	 */
+	if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
+		wq = rcu_dereference(sk->sk_wq);
+		if (wq_has_sleeper(wq))
+			wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
+						POLLWRNORM | POLLWRBAND);
+
+		/* Should agree with poll, otherwise some programs break */
+		if (sock_writeable(sk))
+			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
+	}
+
+	rcu_read_unlock();
+}
+
+static void sock_def_destruct(struct sock *sk)
+{
+	kfree(sk->sk_protinfo);
+}
+
+void sk_send_sigurg(struct sock *sk)
+{
+	if (sk->sk_socket && sk->sk_socket->file)
+		if (send_sigurg(&sk->sk_socket->file->f_owner))
+			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
+}
+EXPORT_SYMBOL(sk_send_sigurg);
+
+void sk_reset_timer(struct sock *sk, struct timer_list* timer,
+		    unsigned long expires)
+{
+	if (!mod_timer(timer, expires))
+		sock_hold(sk);
+}
+EXPORT_SYMBOL(sk_reset_timer);
+
+void sk_stop_timer(struct sock *sk, struct timer_list* timer)
+{
+	if (del_timer(timer))
+		__sock_put(sk);
+}
+EXPORT_SYMBOL(sk_stop_timer);
+
+void sock_init_data(struct socket *sock, struct sock *sk)
+{
+	skb_queue_head_init(&sk->sk_receive_queue);
+	skb_queue_head_init(&sk->sk_write_queue);
+	skb_queue_head_init(&sk->sk_error_queue);
+
+	sk->sk_send_head	=	NULL;
+
+	init_timer(&sk->sk_timer);
+
+	sk->sk_allocation	=	GFP_KERNEL;
+	sk->sk_rcvbuf		=	sysctl_rmem_default;
+	sk->sk_sndbuf		=	sysctl_wmem_default;
+	sk->sk_state		=	TCP_CLOSE;
+	sk_set_socket(sk, sock);
+
+	sock_set_flag(sk, SOCK_ZAPPED);
+
+	if (sock) {
+		sk->sk_type	=	sock->type;
+		sk->sk_wq	=	sock->wq;
+		sock->sk	=	sk;
+	} else
+		sk->sk_wq	=	NULL;
+
+	spin_lock_init(&sk->sk_dst_lock);
+	rwlock_init(&sk->sk_callback_lock);
+	lockdep_set_class_and_name(&sk->sk_callback_lock,
+			af_callback_keys + sk->sk_family,
+			af_family_clock_key_strings[sk->sk_family]);
+
+	sk->sk_state_change	=	sock_def_wakeup;
+	sk->sk_data_ready	=	sock_def_readable;
+	sk->sk_write_space	=	sock_def_write_space;
+	sk->sk_error_report	=	sock_def_error_report;
+	sk->sk_destruct		=	sock_def_destruct;
+
+	sk->sk_frag.page	=	NULL;
+	sk->sk_frag.offset	=	0;
+	sk->sk_peek_off		=	-1;
+
+	sk->sk_peer_pid 	=	NULL;
+	sk->sk_peer_cred	=	NULL;
+	sk->sk_write_pending	=	0;
+	sk->sk_rcvlowat		=	1;
+	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
+	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
+
+	sk->sk_stamp = ktime_set(-1L, 0);
+
+#ifdef CONFIG_NET_RX_BUSY_POLL
+	sk->sk_napi_id		=	0;
+	sk->sk_ll_usec		=	sysctl_net_busy_read;
+#endif
+
+	sk->sk_max_pacing_rate = ~0U;
+	sk->sk_pacing_rate = ~0U;
+	/*
+	 * Before updating sk_refcnt, we must commit prior changes to memory
+	 * (Documentation/RCU/rculist_nulls.txt for details)
+	 */
+	smp_wmb();
+	atomic_set(&sk->sk_refcnt, 1);
+	atomic_set(&sk->sk_drops, 0);
+}
+EXPORT_SYMBOL(sock_init_data);
+
+void lock_sock_nested(struct sock *sk, int subclass)
+{
+	might_sleep();
+	spin_lock_bh(&sk->sk_lock.slock);
+	if (sk->sk_lock.owned)
+		__lock_sock(sk);
+	sk->sk_lock.owned = 1;
+	spin_unlock(&sk->sk_lock.slock);
+	/*
+	 * The sk_lock has mutex_lock() semantics here:
+	 */
+	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
+	local_bh_enable();
+}
+EXPORT_SYMBOL(lock_sock_nested);
+
+void release_sock(struct sock *sk)
+{
+	/*
+	 * The sk_lock has mutex_unlock() semantics:
+	 */
+	mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
+
+	spin_lock_bh(&sk->sk_lock.slock);
+	if (sk->sk_backlog.tail)
+		__release_sock(sk);
+
+	/* Warning : release_cb() might need to release sk ownership,
+	 * ie call sock_release_ownership(sk) before us.
+	 */
+	if (sk->sk_prot->release_cb)
+		sk->sk_prot->release_cb(sk);
+
+	sock_release_ownership(sk);
+	if (waitqueue_active(&sk->sk_lock.wq))
+		wake_up(&sk->sk_lock.wq);
+	spin_unlock_bh(&sk->sk_lock.slock);
+}
+EXPORT_SYMBOL(release_sock);
+
+/**
+ * lock_sock_fast - fast version of lock_sock
+ * @sk: socket
+ *
+ * This version should be used for very small section, where process wont block
+ * return false if fast path is taken
+ *   sk_lock.slock locked, owned = 0, BH disabled
+ * return true if slow path is taken
+ *   sk_lock.slock unlocked, owned = 1, BH enabled
+ */
+bool lock_sock_fast(struct sock *sk)
+{
+	might_sleep();
+	spin_lock_bh(&sk->sk_lock.slock);
+
+	if (!sk->sk_lock.owned)
+		/*
+		 * Note : We must disable BH
+		 */
+		return false;
+
+	__lock_sock(sk);
+	sk->sk_lock.owned = 1;
+	spin_unlock(&sk->sk_lock.slock);
+	/*
+	 * The sk_lock has mutex_lock() semantics here:
+	 */
+	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
+	local_bh_enable();
+	return true;
+}
+EXPORT_SYMBOL(lock_sock_fast);
+
+int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
+{
+	struct timeval tv;
+	if (!sock_flag(sk, SOCK_TIMESTAMP))
+		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
+	tv = ktime_to_timeval(sk->sk_stamp);
+	if (tv.tv_sec == -1)
+		return -ENOENT;
+	if (tv.tv_sec == 0) {
+		sk->sk_stamp = ktime_get_real();
+		tv = ktime_to_timeval(sk->sk_stamp);
+	}
+	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
+}
+EXPORT_SYMBOL(sock_get_timestamp);
+
+int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
+{
+	struct timespec ts;
+	if (!sock_flag(sk, SOCK_TIMESTAMP))
+		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
+	ts = ktime_to_timespec(sk->sk_stamp);
+	if (ts.tv_sec == -1)
+		return -ENOENT;
+	if (ts.tv_sec == 0) {
+		sk->sk_stamp = ktime_get_real();
+		ts = ktime_to_timespec(sk->sk_stamp);
+	}
+	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
+}
+EXPORT_SYMBOL(sock_get_timestampns);
+
+void sock_enable_timestamp(struct sock *sk, int flag)
+{
+	if (!sock_flag(sk, flag)) {
+		unsigned long previous_flags = sk->sk_flags;
+
+		sock_set_flag(sk, flag);
+		/*
+		 * we just set one of the two flags which require net
+		 * time stamping, but time stamping might have been on
+		 * already because of the other one
+		 */
+		if (!(previous_flags & SK_FLAGS_TIMESTAMP))
+			net_enable_timestamp();
+	}
+}
+
+int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
+		       int level, int type)
+{
+	struct sock_exterr_skb *serr;
+	struct sk_buff *skb;
+	int copied, err;
+
+	err = -EAGAIN;
+	skb = sock_dequeue_err_skb(sk);
+	if (skb == NULL)
+		goto out;
+
+	copied = skb->len;
+	if (copied > len) {
+		msg->msg_flags |= MSG_TRUNC;
+		copied = len;
+	}
+	err = skb_copy_datagram_msg(skb, 0, msg, copied);
+	if (err)
+		goto out_free_skb;
+
+	sock_recv_timestamp(msg, sk, skb);
+
+	serr = SKB_EXT_ERR(skb);
+	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
+
+	msg->msg_flags |= MSG_ERRQUEUE;
+	err = copied;
+
+out_free_skb:
+	kfree_skb(skb);
+out:
+	return err;
+}
+EXPORT_SYMBOL(sock_recv_errqueue);
+
+/*
+ *	Get a socket option on an socket.
+ *
+ *	FIX: POSIX 1003.1g is very ambiguous here. It states that
+ *	asynchronous errors should be reported by getsockopt. We assume
+ *	this means if you specify SO_ERROR (otherwise whats the point of it).
+ */
+int sock_common_getsockopt(struct socket *sock, int level, int optname,
+			   char __user *optval, int __user *optlen)
+{
+	struct sock *sk = sock->sk;
+
+	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
+}
+EXPORT_SYMBOL(sock_common_getsockopt);
+
+#ifdef CONFIG_COMPAT
+int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
+				  char __user *optval, int __user *optlen)
+{
+	struct sock *sk = sock->sk;
+
+	if (sk->sk_prot->compat_getsockopt != NULL)
+		return sk->sk_prot->compat_getsockopt(sk, level, optname,
+						      optval, optlen);
+	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
+}
+EXPORT_SYMBOL(compat_sock_common_getsockopt);
+#endif
+
+int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
+			int flags)
+{
+	struct sock *sk = sock->sk;
+	int addr_len = 0;
+	int err;
+
+	err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
+				   flags & ~MSG_DONTWAIT, &addr_len);
+	if (err >= 0)
+		msg->msg_namelen = addr_len;
+	return err;
+}
+EXPORT_SYMBOL(sock_common_recvmsg);
+
+/*
+ *	Set socket options on an inet socket.
+ */
+int sock_common_setsockopt(struct socket *sock, int level, int optname,
+			   char __user *optval, unsigned int optlen)
+{
+	struct sock *sk = sock->sk;
+
+	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
+}
+EXPORT_SYMBOL(sock_common_setsockopt);
+
+#ifdef CONFIG_COMPAT
+int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
+				  char __user *optval, unsigned int optlen)
+{
+	struct sock *sk = sock->sk;
+
+	if (sk->sk_prot->compat_setsockopt != NULL)
+		return sk->sk_prot->compat_setsockopt(sk, level, optname,
+						      optval, optlen);
+	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
+}
+EXPORT_SYMBOL(compat_sock_common_setsockopt);
+#endif
+
+void sk_common_release(struct sock *sk)
+{
+	if (sk->sk_prot->destroy)
+		sk->sk_prot->destroy(sk);
+
+	/*
+	 * Observation: when sock_common_release is called, processes have
+	 * no access to socket. But net still has.
+	 * Step one, detach it from networking:
+	 *
+	 * A. Remove from hash tables.
+	 */
+
+	sk->sk_prot->unhash(sk);
+
+	/*
+	 * In this point socket cannot receive new packets, but it is possible
+	 * that some packets are in flight because some CPU runs receiver and
+	 * did hash table lookup before we unhashed socket. They will achieve
+	 * receive queue and will be purged by socket destructor.
+	 *
+	 * Also we still have packets pending on receive queue and probably,
+	 * our own packets waiting in device queues. sock_destroy will drain
+	 * receive queue, but transmitted packets will delay socket destruction
+	 * until the last reference will be released.
+	 */
+
+	sock_orphan(sk);
+
+	xfrm_sk_free_policy(sk);
+
+	sk_refcnt_debug_release(sk);
+
+	if (sk->sk_frag.page) {
+		put_page(sk->sk_frag.page);
+		sk->sk_frag.page = NULL;
+	}
+
+	sock_put(sk);
+}
+EXPORT_SYMBOL(sk_common_release);
+
+#ifdef CONFIG_PROC_FS
+#define PROTO_INUSE_NR	64	/* should be enough for the first time */
+struct prot_inuse {
+	int val[PROTO_INUSE_NR];
+};
+
+static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
+
+#ifdef CONFIG_NET_NS
+void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
+{
+	__this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
+}
+EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
+
+int sock_prot_inuse_get(struct net *net, struct proto *prot)
+{
+	int cpu, idx = prot->inuse_idx;
+	int res = 0;
+
+	for_each_possible_cpu(cpu)
+		res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
+
+	return res >= 0 ? res : 0;
+}
+EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
+
+static int __net_init sock_inuse_init_net(struct net *net)
+{
+	net->core.inuse = alloc_percpu(struct prot_inuse);
+	return net->core.inuse ? 0 : -ENOMEM;
+}
+
+static void __net_exit sock_inuse_exit_net(struct net *net)
+{
+	free_percpu(net->core.inuse);
+}
+
+static struct pernet_operations net_inuse_ops = {
+	.init = sock_inuse_init_net,
+	.exit = sock_inuse_exit_net,
+};
+
+static __init int net_inuse_init(void)
+{
+	if (register_pernet_subsys(&net_inuse_ops))
+		panic("Cannot initialize net inuse counters");
+
+	return 0;
+}
+
+core_initcall(net_inuse_init);
+#else
+static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
+
+void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
+{
+	__this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
+}
+EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
+
+int sock_prot_inuse_get(struct net *net, struct proto *prot)
+{
+	int cpu, idx = prot->inuse_idx;
+	int res = 0;
+
+	for_each_possible_cpu(cpu)
+		res += per_cpu(prot_inuse, cpu).val[idx];
+
+	return res >= 0 ? res : 0;
+}
+EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
+#endif
+
+static void assign_proto_idx(struct proto *prot)
+{
+	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
+
+	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
+		pr_err("PROTO_INUSE_NR exhausted\n");
+		return;
+	}
+
+	set_bit(prot->inuse_idx, proto_inuse_idx);
+}
+
+static void release_proto_idx(struct proto *prot)
+{
+	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
+		clear_bit(prot->inuse_idx, proto_inuse_idx);
+}
+#else
+static inline void assign_proto_idx(struct proto *prot)
+{
+}
+
+static inline void release_proto_idx(struct proto *prot)
+{
+}
+#endif
+
+static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
+{
+	if (!rsk_prot)
+		return;
+	kfree(rsk_prot->slab_name);
+	rsk_prot->slab_name = NULL;
+	if (rsk_prot->slab) {
+		kmem_cache_destroy(rsk_prot->slab);
+		rsk_prot->slab = NULL;
+	}
+}
+
+static int req_prot_init(const struct proto *prot)
+{
+	struct request_sock_ops *rsk_prot = prot->rsk_prot;
+
+	if (!rsk_prot)
+		return 0;
+
+	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
+					prot->name);
+	if (!rsk_prot->slab_name)
+		return -ENOMEM;
+
+	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
+					   rsk_prot->obj_size, 0,
+					   0, NULL);
+
+	if (!rsk_prot->slab) {
+		pr_crit("%s: Can't create request sock SLAB cache!\n",
+			prot->name);
+		return -ENOMEM;
+	}
+	return 0;
+}
+
+int proto_register(struct proto *prot, int alloc_slab)
+{
+	if (alloc_slab) {
+		prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
+					SLAB_HWCACHE_ALIGN | prot->slab_flags,
+					NULL);
+
+		if (prot->slab == NULL) {
+			pr_crit("%s: Can't create sock SLAB cache!\n",
+				prot->name);
+			goto out;
+		}
+
+		if (req_prot_init(prot))
+			goto out_free_request_sock_slab;
+
+		if (prot->twsk_prot != NULL) {
+			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
+
+			if (prot->twsk_prot->twsk_slab_name == NULL)
+				goto out_free_request_sock_slab;
+
+			prot->twsk_prot->twsk_slab =
+				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
+						  prot->twsk_prot->twsk_obj_size,
+						  0,
+						  prot->slab_flags,
+						  NULL);
+			if (prot->twsk_prot->twsk_slab == NULL)
+				goto out_free_timewait_sock_slab_name;
+		}
+	}
+
+	mutex_lock(&proto_list_mutex);
+	list_add(&prot->node, &proto_list);
+	assign_proto_idx(prot);
+	mutex_unlock(&proto_list_mutex);
+	return 0;
+
+out_free_timewait_sock_slab_name:
+	kfree(prot->twsk_prot->twsk_slab_name);
+out_free_request_sock_slab:
+	req_prot_cleanup(prot->rsk_prot);
+
+	kmem_cache_destroy(prot->slab);
+	prot->slab = NULL;
+out:
+	return -ENOBUFS;
+}
+EXPORT_SYMBOL(proto_register);
+
+void proto_unregister(struct proto *prot)
+{
+	mutex_lock(&proto_list_mutex);
+	release_proto_idx(prot);
+	list_del(&prot->node);
+	mutex_unlock(&proto_list_mutex);
+
+	if (prot->slab != NULL) {
+		kmem_cache_destroy(prot->slab);
+		prot->slab = NULL;
+	}
+
+	req_prot_cleanup(prot->rsk_prot);
+
+	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
+		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
+		kfree(prot->twsk_prot->twsk_slab_name);
+		prot->twsk_prot->twsk_slab = NULL;
+	}
+}
+EXPORT_SYMBOL(proto_unregister);
+
+#ifdef CONFIG_PROC_FS
+static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
+	__acquires(proto_list_mutex)
+{
+	mutex_lock(&proto_list_mutex);
+	return seq_list_start_head(&proto_list, *pos);
+}
+
+static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	return seq_list_next(v, &proto_list, pos);
+}
+
+static void proto_seq_stop(struct seq_file *seq, void *v)
+	__releases(proto_list_mutex)
+{
+	mutex_unlock(&proto_list_mutex);
+}
+
+static char proto_method_implemented(const void *method)
+{
+	return method == NULL ? 'n' : 'y';
+}
+static long sock_prot_memory_allocated(struct proto *proto)
+{
+	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
+}
+
+static char *sock_prot_memory_pressure(struct proto *proto)
+{
+	return proto->memory_pressure != NULL ?
+	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
+}
+
+static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
+{
+
+	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
+			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
+		   proto->name,
+		   proto->obj_size,
+		   sock_prot_inuse_get(seq_file_net(seq), proto),
+		   sock_prot_memory_allocated(proto),
+		   sock_prot_memory_pressure(proto),
+		   proto->max_header,
+		   proto->slab == NULL ? "no" : "yes",
+		   module_name(proto->owner),
+		   proto_method_implemented(proto->close),
+		   proto_method_implemented(proto->connect),
+		   proto_method_implemented(proto->disconnect),
+		   proto_method_implemented(proto->accept),
+		   proto_method_implemented(proto->ioctl),
+		   proto_method_implemented(proto->init),
+		   proto_method_implemented(proto->destroy),
+		   proto_method_implemented(proto->shutdown),
+		   proto_method_implemented(proto->setsockopt),
+		   proto_method_implemented(proto->getsockopt),
+		   proto_method_implemented(proto->sendmsg),
+		   proto_method_implemented(proto->recvmsg),
+		   proto_method_implemented(proto->sendpage),
+		   proto_method_implemented(proto->bind),
+		   proto_method_implemented(proto->backlog_rcv),
+		   proto_method_implemented(proto->hash),
+		   proto_method_implemented(proto->unhash),
+		   proto_method_implemented(proto->get_port),
+		   proto_method_implemented(proto->enter_memory_pressure));
+}
+
+static int proto_seq_show(struct seq_file *seq, void *v)
+{
+	if (v == &proto_list)
+		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
+			   "protocol",
+			   "size",
+			   "sockets",
+			   "memory",
+			   "press",
+			   "maxhdr",
+			   "slab",
+			   "module",
+			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
+	else
+		proto_seq_printf(seq, list_entry(v, struct proto, node));
+	return 0;
+}
+
+static const struct seq_operations proto_seq_ops = {
+	.start  = proto_seq_start,
+	.next   = proto_seq_next,
+	.stop   = proto_seq_stop,
+	.show   = proto_seq_show,
+};
+
+static int proto_seq_open(struct inode *inode, struct file *file)
+{
+	return seq_open_net(inode, file, &proto_seq_ops,
+			    sizeof(struct seq_net_private));
+}
+
+static const struct file_operations proto_seq_fops = {
+	.owner		= THIS_MODULE,
+	.open		= proto_seq_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= seq_release_net,
+};
+
+static __net_init int proto_init_net(struct net *net)
+{
+	if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
+		return -ENOMEM;
+
+	return 0;
+}
+
+static __net_exit void proto_exit_net(struct net *net)
+{
+	remove_proc_entry("protocols", net->proc_net);
+}
+
+
+static __net_initdata struct pernet_operations proto_net_ops = {
+	.init = proto_init_net,
+	.exit = proto_exit_net,
+};
+
+static int __init proto_init(void)
+{
+	return register_pernet_subsys(&proto_net_ops);
+}
+
+subsys_initcall(proto_init);
+
+#endif /* PROC_FS */