Initial import

1 files changed, 1579 insertions, 0 deletions

diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
new file mode 100644
index 000000000..e51fc3eee
--- /dev/null
+++ b/net/ipv6/udp.c
@@ -0,0 +1,1579 @@
+/*
+ *	UDP over IPv6
+ *	Linux INET6 implementation
+ *
+ *	Authors:
+ *	Pedro Roque		<roque@di.fc.ul.pt>
+ *
+ *	Based on linux/ipv4/udp.c
+ *
+ *	Fixes:
+ *	Hideaki YOSHIFUJI	:	sin6_scope_id support
+ *	YOSHIFUJI Hideaki @USAGI and:	Support IPV6_V6ONLY socket option, which
+ *	Alexey Kuznetsov		allow both IPv4 and IPv6 sockets to bind
+ *					a single port at the same time.
+ *      Kazunori MIYAZAWA @USAGI:       change process style to use ip6_append_data
+ *      YOSHIFUJI Hideaki @USAGI:	convert /proc/net/udp6 to seq_file.
+ *
+ *	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.
+ */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/in6.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/ipv6.h>
+#include <linux/icmpv6.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <asm/uaccess.h>
+
+#include <net/ndisc.h>
+#include <net/protocol.h>
+#include <net/transp_v6.h>
+#include <net/ip6_route.h>
+#include <net/raw.h>
+#include <net/tcp_states.h>
+#include <net/ip6_checksum.h>
+#include <net/xfrm.h>
+#include <net/inet6_hashtables.h>
+#include <net/busy_poll.h>
+
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <trace/events/skb.h>
+#include "udp_impl.h"
+
+static u32 udp6_ehashfn(const struct net *net,
+			const struct in6_addr *laddr,
+			const u16 lport,
+			const struct in6_addr *faddr,
+			const __be16 fport)
+{
+	static u32 udp6_ehash_secret __read_mostly;
+	static u32 udp_ipv6_hash_secret __read_mostly;
+
+	u32 lhash, fhash;
+
+	net_get_random_once(&udp6_ehash_secret,
+			    sizeof(udp6_ehash_secret));
+	net_get_random_once(&udp_ipv6_hash_secret,
+			    sizeof(udp_ipv6_hash_secret));
+
+	lhash = (__force u32)laddr->s6_addr32[3];
+	fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
+
+	return __inet6_ehashfn(lhash, lport, fhash, fport,
+			       udp_ipv6_hash_secret + net_hash_mix(net));
+}
+
+int ipv6_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2)
+{
+	const struct in6_addr *sk2_rcv_saddr6 = inet6_rcv_saddr(sk2);
+	int sk2_ipv6only = inet_v6_ipv6only(sk2);
+	int addr_type = ipv6_addr_type(&sk->sk_v6_rcv_saddr);
+	int addr_type2 = sk2_rcv_saddr6 ? ipv6_addr_type(sk2_rcv_saddr6) : IPV6_ADDR_MAPPED;
+
+	/* if both are mapped, treat as IPv4 */
+	if (addr_type == IPV6_ADDR_MAPPED && addr_type2 == IPV6_ADDR_MAPPED)
+		return (!sk2_ipv6only &&
+			(!sk->sk_rcv_saddr || !sk2->sk_rcv_saddr ||
+			  sk->sk_rcv_saddr == sk2->sk_rcv_saddr));
+
+	if (addr_type2 == IPV6_ADDR_ANY &&
+	    !(sk2_ipv6only && addr_type == IPV6_ADDR_MAPPED))
+		return 1;
+
+	if (addr_type == IPV6_ADDR_ANY &&
+	    !(ipv6_only_sock(sk) && addr_type2 == IPV6_ADDR_MAPPED))
+		return 1;
+
+	if (sk2_rcv_saddr6 &&
+	    ipv6_addr_equal(&sk->sk_v6_rcv_saddr, sk2_rcv_saddr6))
+		return 1;
+
+	return 0;
+}
+
+static u32 udp6_portaddr_hash(const struct net *net,
+			      const struct in6_addr *addr6,
+			      unsigned int port)
+{
+	unsigned int hash, mix = net_hash_mix(net);
+
+	if (ipv6_addr_any(addr6))
+		hash = jhash_1word(0, mix);
+	else if (ipv6_addr_v4mapped(addr6))
+		hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
+	else
+		hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
+
+	return hash ^ port;
+}
+
+int udp_v6_get_port(struct sock *sk, unsigned short snum)
+{
+	unsigned int hash2_nulladdr =
+		udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
+	unsigned int hash2_partial =
+		udp6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
+
+	/* precompute partial secondary hash */
+	udp_sk(sk)->udp_portaddr_hash = hash2_partial;
+	return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal, hash2_nulladdr);
+}
+
+static void udp_v6_rehash(struct sock *sk)
+{
+	u16 new_hash = udp6_portaddr_hash(sock_net(sk),
+					  &sk->sk_v6_rcv_saddr,
+					  inet_sk(sk)->inet_num);
+
+	udp_lib_rehash(sk, new_hash);
+}
+
+static inline int compute_score(struct sock *sk, struct net *net,
+				unsigned short hnum,
+				const struct in6_addr *saddr, __be16 sport,
+				const struct in6_addr *daddr, __be16 dport,
+				int dif)
+{
+	int score;
+	struct inet_sock *inet;
+
+	if (!net_eq(sock_net(sk), net) ||
+	    udp_sk(sk)->udp_port_hash != hnum ||
+	    sk->sk_family != PF_INET6)
+		return -1;
+
+	score = 0;
+	inet = inet_sk(sk);
+
+	if (inet->inet_dport) {
+		if (inet->inet_dport != sport)
+			return -1;
+		score++;
+	}
+
+	if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
+		if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
+			return -1;
+		score++;
+	}
+
+	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
+		if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
+			return -1;
+		score++;
+	}
+
+	if (sk->sk_bound_dev_if) {
+		if (sk->sk_bound_dev_if != dif)
+			return -1;
+		score++;
+	}
+
+	return score;
+}
+
+#define SCORE2_MAX (1 + 1 + 1)
+static inline int compute_score2(struct sock *sk, struct net *net,
+				 const struct in6_addr *saddr, __be16 sport,
+				 const struct in6_addr *daddr,
+				 unsigned short hnum, int dif)
+{
+	int score;
+	struct inet_sock *inet;
+
+	if (!net_eq(sock_net(sk), net) ||
+	    udp_sk(sk)->udp_port_hash != hnum ||
+	    sk->sk_family != PF_INET6)
+		return -1;
+
+	if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
+		return -1;
+
+	score = 0;
+	inet = inet_sk(sk);
+
+	if (inet->inet_dport) {
+		if (inet->inet_dport != sport)
+			return -1;
+		score++;
+	}
+
+	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
+		if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
+			return -1;
+		score++;
+	}
+
+	if (sk->sk_bound_dev_if) {
+		if (sk->sk_bound_dev_if != dif)
+			return -1;
+		score++;
+	}
+
+	return score;
+}
+
+/* called with read_rcu_lock() */
+static struct sock *udp6_lib_lookup2(struct net *net,
+		const struct in6_addr *saddr, __be16 sport,
+		const struct in6_addr *daddr, unsigned int hnum, int dif,
+		struct udp_hslot *hslot2, unsigned int slot2)
+{
+	struct sock *sk, *result;
+	struct hlist_nulls_node *node;
+	int score, badness, matches = 0, reuseport = 0;
+	u32 hash = 0;
+
+begin:
+	result = NULL;
+	badness = -1;
+	udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) {
+		score = compute_score2(sk, net, saddr, sport,
+				      daddr, hnum, dif);
+		if (score > badness) {
+			result = sk;
+			badness = score;
+			reuseport = sk->sk_reuseport;
+			if (reuseport) {
+				hash = udp6_ehashfn(net, daddr, hnum,
+						    saddr, sport);
+				matches = 1;
+			} else if (score == SCORE2_MAX)
+				goto exact_match;
+		} else if (score == badness && reuseport) {
+			matches++;
+			if (reciprocal_scale(hash, matches) == 0)
+				result = sk;
+			hash = next_pseudo_random32(hash);
+		}
+	}
+	/*
+	 * if the nulls value we got at the end of this lookup is
+	 * not the expected one, we must restart lookup.
+	 * We probably met an item that was moved to another chain.
+	 */
+	if (get_nulls_value(node) != slot2)
+		goto begin;
+
+	if (result) {
+exact_match:
+		if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
+			result = NULL;
+		else if (unlikely(compute_score2(result, net, saddr, sport,
+				  daddr, hnum, dif) < badness)) {
+			sock_put(result);
+			goto begin;
+		}
+	}
+	return result;
+}
+
+struct sock *__udp6_lib_lookup(struct net *net,
+				      const struct in6_addr *saddr, __be16 sport,
+				      const struct in6_addr *daddr, __be16 dport,
+				      int dif, struct udp_table *udptable)
+{
+	struct sock *sk, *result;
+	struct hlist_nulls_node *node;
+	unsigned short hnum = ntohs(dport);
+	unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
+	struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
+	int score, badness, matches = 0, reuseport = 0;
+	u32 hash = 0;
+
+	rcu_read_lock();
+	if (hslot->count > 10) {
+		hash2 = udp6_portaddr_hash(net, daddr, hnum);
+		slot2 = hash2 & udptable->mask;
+		hslot2 = &udptable->hash2[slot2];
+		if (hslot->count < hslot2->count)
+			goto begin;
+
+		result = udp6_lib_lookup2(net, saddr, sport,
+					  daddr, hnum, dif,
+					  hslot2, slot2);
+		if (!result) {
+			hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum);
+			slot2 = hash2 & udptable->mask;
+			hslot2 = &udptable->hash2[slot2];
+			if (hslot->count < hslot2->count)
+				goto begin;
+
+			result = udp6_lib_lookup2(net, saddr, sport,
+						  &in6addr_any, hnum, dif,
+						  hslot2, slot2);
+		}
+		rcu_read_unlock();
+		return result;
+	}
+begin:
+	result = NULL;
+	badness = -1;
+	sk_nulls_for_each_rcu(sk, node, &hslot->head) {
+		score = compute_score(sk, net, hnum, saddr, sport, daddr, dport, dif);
+		if (score > badness) {
+			result = sk;
+			badness = score;
+			reuseport = sk->sk_reuseport;
+			if (reuseport) {
+				hash = udp6_ehashfn(net, daddr, hnum,
+						    saddr, sport);
+				matches = 1;
+			}
+		} else if (score == badness && reuseport) {
+			matches++;
+			if (reciprocal_scale(hash, matches) == 0)
+				result = sk;
+			hash = next_pseudo_random32(hash);
+		}
+	}
+	/*
+	 * if the nulls value we got at the end of this lookup is
+	 * not the expected one, we must restart lookup.
+	 * We probably met an item that was moved to another chain.
+	 */
+	if (get_nulls_value(node) != slot)
+		goto begin;
+
+	if (result) {
+		if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
+			result = NULL;
+		else if (unlikely(compute_score(result, net, hnum, saddr, sport,
+					daddr, dport, dif) < badness)) {
+			sock_put(result);
+			goto begin;
+		}
+	}
+	rcu_read_unlock();
+	return result;
+}
+EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
+
+static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
+					  __be16 sport, __be16 dport,
+					  struct udp_table *udptable)
+{
+	struct sock *sk;
+	const struct ipv6hdr *iph = ipv6_hdr(skb);
+
+	sk = skb_steal_sock(skb);
+	if (unlikely(sk))
+		return sk;
+	return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport,
+				 &iph->daddr, dport, inet6_iif(skb),
+				 udptable);
+}
+
+struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
+			     const struct in6_addr *daddr, __be16 dport, int dif)
+{
+	return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table);
+}
+EXPORT_SYMBOL_GPL(udp6_lib_lookup);
+
+/*
+ *	This should be easy, if there is something there we
+ *	return it, otherwise we block.
+ */
+
+int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
+		  int noblock, int flags, int *addr_len)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct inet_sock *inet = inet_sk(sk);
+	struct sk_buff *skb;
+	unsigned int ulen, copied;
+	int peeked, off = 0;
+	int err;
+	int is_udplite = IS_UDPLITE(sk);
+	int is_udp4;
+	bool slow;
+
+	if (flags & MSG_ERRQUEUE)
+		return ipv6_recv_error(sk, msg, len, addr_len);
+
+	if (np->rxpmtu && np->rxopt.bits.rxpmtu)
+		return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
+
+try_again:
+	skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
+				  &peeked, &off, &err);
+	if (!skb)
+		goto out;
+
+	ulen = skb->len - sizeof(struct udphdr);
+	copied = len;
+	if (copied > ulen)
+		copied = ulen;
+	else if (copied < ulen)
+		msg->msg_flags |= MSG_TRUNC;
+
+	is_udp4 = (skb->protocol == htons(ETH_P_IP));
+
+	/*
+	 * If checksum is needed at all, try to do it while copying the
+	 * data.  If the data is truncated, or if we only want a partial
+	 * coverage checksum (UDP-Lite), do it before the copy.
+	 */
+
+	if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) {
+		if (udp_lib_checksum_complete(skb))
+			goto csum_copy_err;
+	}
+
+	if (skb_csum_unnecessary(skb))
+		err = skb_copy_datagram_msg(skb, sizeof(struct udphdr),
+					    msg, copied);
+	else {
+		err = skb_copy_and_csum_datagram_msg(skb, sizeof(struct udphdr), msg);
+		if (err == -EINVAL)
+			goto csum_copy_err;
+	}
+	if (unlikely(err)) {
+		trace_kfree_skb(skb, udpv6_recvmsg);
+		if (!peeked) {
+			atomic_inc(&sk->sk_drops);
+			if (is_udp4)
+				UDP_INC_STATS_USER(sock_net(sk),
+						   UDP_MIB_INERRORS,
+						   is_udplite);
+			else
+				UDP6_INC_STATS_USER(sock_net(sk),
+						    UDP_MIB_INERRORS,
+						    is_udplite);
+		}
+		goto out_free;
+	}
+	if (!peeked) {
+		if (is_udp4)
+			UDP_INC_STATS_USER(sock_net(sk),
+					UDP_MIB_INDATAGRAMS, is_udplite);
+		else
+			UDP6_INC_STATS_USER(sock_net(sk),
+					UDP_MIB_INDATAGRAMS, is_udplite);
+	}
+
+	sock_recv_ts_and_drops(msg, sk, skb);
+
+	/* Copy the address. */
+	if (msg->msg_name) {
+		DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
+		sin6->sin6_family = AF_INET6;
+		sin6->sin6_port = udp_hdr(skb)->source;
+		sin6->sin6_flowinfo = 0;
+
+		if (is_udp4) {
+			ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
+					       &sin6->sin6_addr);
+			sin6->sin6_scope_id = 0;
+		} else {
+			sin6->sin6_addr = ipv6_hdr(skb)->saddr;
+			sin6->sin6_scope_id =
+				ipv6_iface_scope_id(&sin6->sin6_addr,
+						    inet6_iif(skb));
+		}
+		*addr_len = sizeof(*sin6);
+	}
+
+	if (np->rxopt.all)
+		ip6_datagram_recv_common_ctl(sk, msg, skb);
+
+	if (is_udp4) {
+		if (inet->cmsg_flags)
+			ip_cmsg_recv(msg, skb);
+	} else {
+		if (np->rxopt.all)
+			ip6_datagram_recv_specific_ctl(sk, msg, skb);
+	}
+
+	err = copied;
+	if (flags & MSG_TRUNC)
+		err = ulen;
+
+out_free:
+	skb_free_datagram_locked(sk, skb);
+out:
+	return err;
+
+csum_copy_err:
+	slow = lock_sock_fast(sk);
+	if (!skb_kill_datagram(sk, skb, flags)) {
+		if (is_udp4) {
+			UDP_INC_STATS_USER(sock_net(sk),
+					UDP_MIB_CSUMERRORS, is_udplite);
+			UDP_INC_STATS_USER(sock_net(sk),
+					UDP_MIB_INERRORS, is_udplite);
+		} else {
+			UDP6_INC_STATS_USER(sock_net(sk),
+					UDP_MIB_CSUMERRORS, is_udplite);
+			UDP6_INC_STATS_USER(sock_net(sk),
+					UDP_MIB_INERRORS, is_udplite);
+		}
+	}
+	unlock_sock_fast(sk, slow);
+
+	/* starting over for a new packet, but check if we need to yield */
+	cond_resched();
+	msg->msg_flags &= ~MSG_TRUNC;
+	goto try_again;
+}
+
+void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
+		    u8 type, u8 code, int offset, __be32 info,
+		    struct udp_table *udptable)
+{
+	struct ipv6_pinfo *np;
+	const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
+	const struct in6_addr *saddr = &hdr->saddr;
+	const struct in6_addr *daddr = &hdr->daddr;
+	struct udphdr *uh = (struct udphdr *)(skb->data+offset);
+	struct sock *sk;
+	int err;
+	struct net *net = dev_net(skb->dev);
+
+	sk = __udp6_lib_lookup(net, daddr, uh->dest,
+			       saddr, uh->source, inet6_iif(skb), udptable);
+	if (!sk) {
+		ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
+				   ICMP6_MIB_INERRORS);
+		return;
+	}
+
+	if (type == ICMPV6_PKT_TOOBIG) {
+		if (!ip6_sk_accept_pmtu(sk))
+			goto out;
+		ip6_sk_update_pmtu(skb, sk, info);
+	}
+	if (type == NDISC_REDIRECT) {
+		ip6_sk_redirect(skb, sk);
+		goto out;
+	}
+
+	np = inet6_sk(sk);
+
+	if (!icmpv6_err_convert(type, code, &err) && !np->recverr)
+		goto out;
+
+	if (sk->sk_state != TCP_ESTABLISHED && !np->recverr)
+		goto out;
+
+	if (np->recverr)
+		ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
+
+	sk->sk_err = err;
+	sk->sk_error_report(sk);
+out:
+	sock_put(sk);
+}
+
+static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
+{
+	int rc;
+
+	if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
+		sock_rps_save_rxhash(sk, skb);
+		sk_mark_napi_id(sk, skb);
+		sk_incoming_cpu_update(sk);
+	}
+
+	rc = sock_queue_rcv_skb(sk, skb);
+	if (rc < 0) {
+		int is_udplite = IS_UDPLITE(sk);
+
+		/* Note that an ENOMEM error is charged twice */
+		if (rc == -ENOMEM)
+			UDP6_INC_STATS_BH(sock_net(sk),
+					UDP_MIB_RCVBUFERRORS, is_udplite);
+		UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
+		kfree_skb(skb);
+		return -1;
+	}
+	return 0;
+}
+
+static __inline__ void udpv6_err(struct sk_buff *skb,
+				 struct inet6_skb_parm *opt, u8 type,
+				 u8 code, int offset, __be32 info)
+{
+	__udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
+}
+
+static struct static_key udpv6_encap_needed __read_mostly;
+void udpv6_encap_enable(void)
+{
+	if (!static_key_enabled(&udpv6_encap_needed))
+		static_key_slow_inc(&udpv6_encap_needed);
+}
+EXPORT_SYMBOL(udpv6_encap_enable);
+
+int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
+{
+	struct udp_sock *up = udp_sk(sk);
+	int rc;
+	int is_udplite = IS_UDPLITE(sk);
+
+	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
+		goto drop;
+
+	if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
+		int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
+
+		/*
+		 * This is an encapsulation socket so pass the skb to
+		 * the socket's udp_encap_rcv() hook. Otherwise, just
+		 * fall through and pass this up the UDP socket.
+		 * up->encap_rcv() returns the following value:
+		 * =0 if skb was successfully passed to the encap
+		 *    handler or was discarded by it.
+		 * >0 if skb should be passed on to UDP.
+		 * <0 if skb should be resubmitted as proto -N
+		 */
+
+		/* if we're overly short, let UDP handle it */
+		encap_rcv = ACCESS_ONCE(up->encap_rcv);
+		if (skb->len > sizeof(struct udphdr) && encap_rcv) {
+			int ret;
+
+			/* Verify checksum before giving to encap */
+			if (udp_lib_checksum_complete(skb))
+				goto csum_error;
+
+			ret = encap_rcv(sk, skb);
+			if (ret <= 0) {
+				UDP_INC_STATS_BH(sock_net(sk),
+						 UDP_MIB_INDATAGRAMS,
+						 is_udplite);
+				return -ret;
+			}
+		}
+
+		/* FALLTHROUGH -- it's a UDP Packet */
+	}
+
+	/*
+	 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
+	 */
+	if ((is_udplite & UDPLITE_RECV_CC)  &&  UDP_SKB_CB(skb)->partial_cov) {
+
+		if (up->pcrlen == 0) {          /* full coverage was set  */
+			net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n",
+					    UDP_SKB_CB(skb)->cscov, skb->len);
+			goto drop;
+		}
+		if (UDP_SKB_CB(skb)->cscov  <  up->pcrlen) {
+			net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n",
+					    UDP_SKB_CB(skb)->cscov, up->pcrlen);
+			goto drop;
+		}
+	}
+
+	if (rcu_access_pointer(sk->sk_filter)) {
+		if (udp_lib_checksum_complete(skb))
+			goto csum_error;
+	}
+
+	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
+		UDP6_INC_STATS_BH(sock_net(sk),
+				  UDP_MIB_RCVBUFERRORS, is_udplite);
+		goto drop;
+	}
+
+	skb_dst_drop(skb);
+
+	bh_lock_sock(sk);
+	rc = 0;
+	if (!sock_owned_by_user(sk))
+		rc = __udpv6_queue_rcv_skb(sk, skb);
+	else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
+		bh_unlock_sock(sk);
+		goto drop;
+	}
+	bh_unlock_sock(sk);
+
+	return rc;
+
+csum_error:
+	UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
+drop:
+	UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
+	atomic_inc(&sk->sk_drops);
+	kfree_skb(skb);
+	return -1;
+}
+
+static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk,
+				   __be16 loc_port, const struct in6_addr *loc_addr,
+				   __be16 rmt_port, const struct in6_addr *rmt_addr,
+				   int dif, unsigned short hnum)
+{
+	struct inet_sock *inet = inet_sk(sk);
+
+	if (!net_eq(sock_net(sk), net))
+		return false;
+
+	if (udp_sk(sk)->udp_port_hash != hnum ||
+	    sk->sk_family != PF_INET6 ||
+	    (inet->inet_dport && inet->inet_dport != rmt_port) ||
+	    (!ipv6_addr_any(&sk->sk_v6_daddr) &&
+		    !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
+	    (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif) ||
+	    (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
+		    !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr)))
+		return false;
+	if (!inet6_mc_check(sk, loc_addr, rmt_addr))
+		return false;
+	return true;
+}
+
+static void flush_stack(struct sock **stack, unsigned int count,
+			struct sk_buff *skb, unsigned int final)
+{
+	struct sk_buff *skb1 = NULL;
+	struct sock *sk;
+	unsigned int i;
+
+	for (i = 0; i < count; i++) {
+		sk = stack[i];
+		if (likely(!skb1))
+			skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
+		if (!skb1) {
+			atomic_inc(&sk->sk_drops);
+			UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS,
+					  IS_UDPLITE(sk));
+			UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS,
+					  IS_UDPLITE(sk));
+		}
+
+		if (skb1 && udpv6_queue_rcv_skb(sk, skb1) <= 0)
+			skb1 = NULL;
+		sock_put(sk);
+	}
+	if (unlikely(skb1))
+		kfree_skb(skb1);
+}
+
+static void udp6_csum_zero_error(struct sk_buff *skb)
+{
+	/* RFC 2460 section 8.1 says that we SHOULD log
+	 * this error. Well, it is reasonable.
+	 */
+	net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n",
+			    &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source),
+			    &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest));
+}
+
+/*
+ * Note: called only from the BH handler context,
+ * so we don't need to lock the hashes.
+ */
+static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
+		const struct in6_addr *saddr, const struct in6_addr *daddr,
+		struct udp_table *udptable, int proto)
+{
+	struct sock *sk, *stack[256 / sizeof(struct sock *)];
+	const struct udphdr *uh = udp_hdr(skb);
+	struct hlist_nulls_node *node;
+	unsigned short hnum = ntohs(uh->dest);
+	struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum);
+	int dif = inet6_iif(skb);
+	unsigned int count = 0, offset = offsetof(typeof(*sk), sk_nulls_node);
+	unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10);
+	bool inner_flushed = false;
+
+	if (use_hash2) {
+		hash2_any = udp6_portaddr_hash(net, &in6addr_any, hnum) &
+			    udp_table.mask;
+		hash2 = udp6_portaddr_hash(net, daddr, hnum) & udp_table.mask;
+start_lookup:
+		hslot = &udp_table.hash2[hash2];
+		offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
+	}
+
+	spin_lock(&hslot->lock);
+	sk_nulls_for_each_entry_offset(sk, node, &hslot->head, offset) {
+		if (__udp_v6_is_mcast_sock(net, sk,
+					   uh->dest, daddr,
+					   uh->source, saddr,
+					   dif, hnum) &&
+		    /* If zero checksum and no_check is not on for
+		     * the socket then skip it.
+		     */
+		    (uh->check || udp_sk(sk)->no_check6_rx)) {
+			if (unlikely(count == ARRAY_SIZE(stack))) {
+				flush_stack(stack, count, skb, ~0);
+				inner_flushed = true;
+				count = 0;
+			}
+			stack[count++] = sk;
+			sock_hold(sk);
+		}
+	}
+
+	spin_unlock(&hslot->lock);
+
+	/* Also lookup *:port if we are using hash2 and haven't done so yet. */
+	if (use_hash2 && hash2 != hash2_any) {
+		hash2 = hash2_any;
+		goto start_lookup;
+	}
+
+	if (count) {
+		flush_stack(stack, count, skb, count - 1);
+	} else {
+		if (!inner_flushed)
+			UDP_INC_STATS_BH(net, UDP_MIB_IGNOREDMULTI,
+					 proto == IPPROTO_UDPLITE);
+		consume_skb(skb);
+	}
+	return 0;
+}
+
+int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
+		   int proto)
+{
+	struct net *net = dev_net(skb->dev);
+	struct sock *sk;
+	struct udphdr *uh;
+	const struct in6_addr *saddr, *daddr;
+	u32 ulen = 0;
+
+	if (!pskb_may_pull(skb, sizeof(struct udphdr)))
+		goto discard;
+
+	saddr = &ipv6_hdr(skb)->saddr;
+	daddr = &ipv6_hdr(skb)->daddr;
+	uh = udp_hdr(skb);
+
+	ulen = ntohs(uh->len);
+	if (ulen > skb->len)
+		goto short_packet;
+
+	if (proto == IPPROTO_UDP) {
+		/* UDP validates ulen. */
+
+		/* Check for jumbo payload */
+		if (ulen == 0)
+			ulen = skb->len;
+
+		if (ulen < sizeof(*uh))
+			goto short_packet;
+
+		if (ulen < skb->len) {
+			if (pskb_trim_rcsum(skb, ulen))
+				goto short_packet;
+			saddr = &ipv6_hdr(skb)->saddr;
+			daddr = &ipv6_hdr(skb)->daddr;
+			uh = udp_hdr(skb);
+		}
+	}
+
+	if (udp6_csum_init(skb, uh, proto))
+		goto csum_error;
+
+	/*
+	 *	Multicast receive code
+	 */
+	if (ipv6_addr_is_multicast(daddr))
+		return __udp6_lib_mcast_deliver(net, skb,
+				saddr, daddr, udptable, proto);
+
+	/* Unicast */
+
+	/*
+	 * check socket cache ... must talk to Alan about his plans
+	 * for sock caches... i'll skip this for now.
+	 */
+	sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
+	if (sk) {
+		int ret;
+
+		if (!uh->check && !udp_sk(sk)->no_check6_rx) {
+			sock_put(sk);
+			udp6_csum_zero_error(skb);
+			goto csum_error;
+		}
+
+		if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk))
+			skb_checksum_try_convert(skb, IPPROTO_UDP, uh->check,
+						 ip6_compute_pseudo);
+
+		ret = udpv6_queue_rcv_skb(sk, skb);
+		sock_put(sk);
+
+		/* a return value > 0 means to resubmit the input, but
+		 * it wants the return to be -protocol, or 0
+		 */
+		if (ret > 0)
+			return -ret;
+
+		return 0;
+	}
+
+	if (!uh->check) {
+		udp6_csum_zero_error(skb);
+		goto csum_error;
+	}
+
+	if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
+		goto discard;
+
+	if (udp_lib_checksum_complete(skb))
+		goto csum_error;
+
+	UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
+	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
+
+	kfree_skb(skb);
+	return 0;
+
+short_packet:
+	net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
+			    proto == IPPROTO_UDPLITE ? "-Lite" : "",
+			    saddr, ntohs(uh->source),
+			    ulen, skb->len,
+			    daddr, ntohs(uh->dest));
+	goto discard;
+csum_error:
+	UDP6_INC_STATS_BH(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
+discard:
+	UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
+	kfree_skb(skb);
+	return 0;
+}
+
+static __inline__ int udpv6_rcv(struct sk_buff *skb)
+{
+	return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
+}
+
+/*
+ * Throw away all pending data and cancel the corking. Socket is locked.
+ */
+static void udp_v6_flush_pending_frames(struct sock *sk)
+{
+	struct udp_sock *up = udp_sk(sk);
+
+	if (up->pending == AF_INET)
+		udp_flush_pending_frames(sk);
+	else if (up->pending) {
+		up->len = 0;
+		up->pending = 0;
+		ip6_flush_pending_frames(sk);
+	}
+}
+
+/**
+ *	udp6_hwcsum_outgoing  -  handle outgoing HW checksumming
+ *	@sk:	socket we are sending on
+ *	@skb:	sk_buff containing the filled-in UDP header
+ *		(checksum field must be zeroed out)
+ */
+static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
+				 const struct in6_addr *saddr,
+				 const struct in6_addr *daddr, int len)
+{
+	unsigned int offset;
+	struct udphdr *uh = udp_hdr(skb);
+	struct sk_buff *frags = skb_shinfo(skb)->frag_list;
+	__wsum csum = 0;
+
+	if (!frags) {
+		/* Only one fragment on the socket.  */
+		skb->csum_start = skb_transport_header(skb) - skb->head;
+		skb->csum_offset = offsetof(struct udphdr, check);
+		uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
+	} else {
+		/*
+		 * HW-checksum won't work as there are two or more
+		 * fragments on the socket so that all csums of sk_buffs
+		 * should be together
+		 */
+		offset = skb_transport_offset(skb);
+		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
+
+		skb->ip_summed = CHECKSUM_NONE;
+
+		do {
+			csum = csum_add(csum, frags->csum);
+		} while ((frags = frags->next));
+
+		uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
+					    csum);
+		if (uh->check == 0)
+			uh->check = CSUM_MANGLED_0;
+	}
+}
+
+/*
+ *	Sending
+ */
+
+static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6)
+{
+	struct sock *sk = skb->sk;
+	struct udphdr *uh;
+	int err = 0;
+	int is_udplite = IS_UDPLITE(sk);
+	__wsum csum = 0;
+	int offset = skb_transport_offset(skb);
+	int len = skb->len - offset;
+
+	/*
+	 * Create a UDP header
+	 */
+	uh = udp_hdr(skb);
+	uh->source = fl6->fl6_sport;
+	uh->dest = fl6->fl6_dport;
+	uh->len = htons(len);
+	uh->check = 0;
+
+	if (is_udplite)
+		csum = udplite_csum(skb);
+	else if (udp_sk(sk)->no_check6_tx) {   /* UDP csum disabled */
+		skb->ip_summed = CHECKSUM_NONE;
+		goto send;
+	} else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
+		udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len);
+		goto send;
+	} else
+		csum = udp_csum(skb);
+
+	/* add protocol-dependent pseudo-header */
+	uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
+				    len, fl6->flowi6_proto, csum);
+	if (uh->check == 0)
+		uh->check = CSUM_MANGLED_0;
+
+send:
+	err = ip6_send_skb(skb);
+	if (err) {
+		if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
+			UDP6_INC_STATS_USER(sock_net(sk),
+					    UDP_MIB_SNDBUFERRORS, is_udplite);
+			err = 0;
+		}
+	} else
+		UDP6_INC_STATS_USER(sock_net(sk),
+				    UDP_MIB_OUTDATAGRAMS, is_udplite);
+	return err;
+}
+
+static int udp_v6_push_pending_frames(struct sock *sk)
+{
+	struct sk_buff *skb;
+	struct udp_sock  *up = udp_sk(sk);
+	struct flowi6 fl6;
+	int err = 0;
+
+	if (up->pending == AF_INET)
+		return udp_push_pending_frames(sk);
+
+	/* ip6_finish_skb will release the cork, so make a copy of
+	 * fl6 here.
+	 */
+	fl6 = inet_sk(sk)->cork.fl.u.ip6;
+
+	skb = ip6_finish_skb(sk);
+	if (!skb)
+		goto out;
+
+	err = udp_v6_send_skb(skb, &fl6);
+
+out:
+	up->len = 0;
+	up->pending = 0;
+	return err;
+}
+
+int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
+{
+	struct ipv6_txoptions opt_space;
+	struct udp_sock *up = udp_sk(sk);
+	struct inet_sock *inet = inet_sk(sk);
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
+	struct in6_addr *daddr, *final_p, final;
+	struct ipv6_txoptions *opt = NULL;
+	struct ip6_flowlabel *flowlabel = NULL;
+	struct flowi6 fl6;
+	struct dst_entry *dst;
+	int addr_len = msg->msg_namelen;
+	int ulen = len;
+	int hlimit = -1;
+	int tclass = -1;
+	int dontfrag = -1;
+	int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
+	int err;
+	int connected = 0;
+	int is_udplite = IS_UDPLITE(sk);
+	int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
+
+	/* destination address check */
+	if (sin6) {
+		if (addr_len < offsetof(struct sockaddr, sa_data))
+			return -EINVAL;
+
+		switch (sin6->sin6_family) {
+		case AF_INET6:
+			if (addr_len < SIN6_LEN_RFC2133)
+				return -EINVAL;
+			daddr = &sin6->sin6_addr;
+			break;
+		case AF_INET:
+			goto do_udp_sendmsg;
+		case AF_UNSPEC:
+			msg->msg_name = sin6 = NULL;
+			msg->msg_namelen = addr_len = 0;
+			daddr = NULL;
+			break;
+		default:
+			return -EINVAL;
+		}
+	} else if (!up->pending) {
+		if (sk->sk_state != TCP_ESTABLISHED)
+			return -EDESTADDRREQ;
+		daddr = &sk->sk_v6_daddr;
+	} else
+		daddr = NULL;
+
+	if (daddr) {
+		if (ipv6_addr_v4mapped(daddr)) {
+			struct sockaddr_in sin;
+			sin.sin_family = AF_INET;
+			sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
+			sin.sin_addr.s_addr = daddr->s6_addr32[3];
+			msg->msg_name = &sin;
+			msg->msg_namelen = sizeof(sin);
+do_udp_sendmsg:
+			if (__ipv6_only_sock(sk))
+				return -ENETUNREACH;
+			return udp_sendmsg(sk, msg, len);
+		}
+	}
+
+	if (up->pending == AF_INET)
+		return udp_sendmsg(sk, msg, len);
+
+	/* Rough check on arithmetic overflow,
+	   better check is made in ip6_append_data().
+	   */
+	if (len > INT_MAX - sizeof(struct udphdr))
+		return -EMSGSIZE;
+
+	getfrag  =  is_udplite ?  udplite_getfrag : ip_generic_getfrag;
+	if (up->pending) {
+		/*
+		 * There are pending frames.
+		 * The socket lock must be held while it's corked.
+		 */
+		lock_sock(sk);
+		if (likely(up->pending)) {
+			if (unlikely(up->pending != AF_INET6)) {
+				release_sock(sk);
+				return -EAFNOSUPPORT;
+			}
+			dst = NULL;
+			goto do_append_data;
+		}
+		release_sock(sk);
+	}
+	ulen += sizeof(struct udphdr);
+
+	memset(&fl6, 0, sizeof(fl6));
+
+	if (sin6) {
+		if (sin6->sin6_port == 0)
+			return -EINVAL;
+
+		fl6.fl6_dport = sin6->sin6_port;
+		daddr = &sin6->sin6_addr;
+
+		if (np->sndflow) {
+			fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
+			if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
+				flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
+				if (!flowlabel)
+					return -EINVAL;
+			}
+		}
+
+		/*
+		 * Otherwise it will be difficult to maintain
+		 * sk->sk_dst_cache.
+		 */
+		if (sk->sk_state == TCP_ESTABLISHED &&
+		    ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
+			daddr = &sk->sk_v6_daddr;
+
+		if (addr_len >= sizeof(struct sockaddr_in6) &&
+		    sin6->sin6_scope_id &&
+		    __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
+			fl6.flowi6_oif = sin6->sin6_scope_id;
+	} else {
+		if (sk->sk_state != TCP_ESTABLISHED)
+			return -EDESTADDRREQ;
+
+		fl6.fl6_dport = inet->inet_dport;
+		daddr = &sk->sk_v6_daddr;
+		fl6.flowlabel = np->flow_label;
+		connected = 1;
+	}
+
+	if (!fl6.flowi6_oif)
+		fl6.flowi6_oif = sk->sk_bound_dev_if;
+
+	if (!fl6.flowi6_oif)
+		fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
+
+	fl6.flowi6_mark = sk->sk_mark;
+
+	if (msg->msg_controllen) {
+		opt = &opt_space;
+		memset(opt, 0, sizeof(struct ipv6_txoptions));
+		opt->tot_len = sizeof(*opt);
+
+		err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
+					    &hlimit, &tclass, &dontfrag);
+		if (err < 0) {
+			fl6_sock_release(flowlabel);
+			return err;
+		}
+		if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
+			flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
+			if (!flowlabel)
+				return -EINVAL;
+		}
+		if (!(opt->opt_nflen|opt->opt_flen))
+			opt = NULL;
+		connected = 0;
+	}
+	if (!opt)
+		opt = np->opt;
+	if (flowlabel)
+		opt = fl6_merge_options(&opt_space, flowlabel, opt);
+	opt = ipv6_fixup_options(&opt_space, opt);
+
+	fl6.flowi6_proto = sk->sk_protocol;
+	if (!ipv6_addr_any(daddr))
+		fl6.daddr = *daddr;
+	else
+		fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
+	if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
+		fl6.saddr = np->saddr;
+	fl6.fl6_sport = inet->inet_sport;
+
+	final_p = fl6_update_dst(&fl6, opt, &final);
+	if (final_p)
+		connected = 0;
+
+	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
+		fl6.flowi6_oif = np->mcast_oif;
+		connected = 0;
+	} else if (!fl6.flowi6_oif)
+		fl6.flowi6_oif = np->ucast_oif;
+
+	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
+
+	dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p);
+	if (IS_ERR(dst)) {
+		err = PTR_ERR(dst);
+		dst = NULL;
+		goto out;
+	}
+
+	if (hlimit < 0)
+		hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
+
+	if (tclass < 0)
+		tclass = np->tclass;
+
+	if (msg->msg_flags&MSG_CONFIRM)
+		goto do_confirm;
+back_from_confirm:
+
+	/* Lockless fast path for the non-corking case */
+	if (!corkreq) {
+		struct sk_buff *skb;
+
+		skb = ip6_make_skb(sk, getfrag, msg, ulen,
+				   sizeof(struct udphdr), hlimit, tclass, opt,
+				   &fl6, (struct rt6_info *)dst,
+				   msg->msg_flags, dontfrag);
+		err = PTR_ERR(skb);
+		if (!IS_ERR_OR_NULL(skb))
+			err = udp_v6_send_skb(skb, &fl6);
+		goto release_dst;
+	}
+
+	lock_sock(sk);
+	if (unlikely(up->pending)) {
+		/* The socket is already corked while preparing it. */
+		/* ... which is an evident application bug. --ANK */
+		release_sock(sk);
+
+		net_dbg_ratelimited("udp cork app bug 2\n");
+		err = -EINVAL;
+		goto out;
+	}
+
+	up->pending = AF_INET6;
+
+do_append_data:
+	if (dontfrag < 0)
+		dontfrag = np->dontfrag;
+	up->len += ulen;
+	err = ip6_append_data(sk, getfrag, msg, ulen,
+		sizeof(struct udphdr), hlimit, tclass, opt, &fl6,
+		(struct rt6_info *)dst,
+		corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag);
+	if (err)
+		udp_v6_flush_pending_frames(sk);
+	else if (!corkreq)
+		err = udp_v6_push_pending_frames(sk);
+	else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
+		up->pending = 0;
+
+	if (err > 0)
+		err = np->recverr ? net_xmit_errno(err) : 0;
+	release_sock(sk);
+
+release_dst:
+	if (dst) {
+		if (connected) {
+			ip6_dst_store(sk, dst,
+				      ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ?
+				      &sk->sk_v6_daddr : NULL,
+#ifdef CONFIG_IPV6_SUBTREES
+				      ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
+				      &np->saddr :
+#endif
+				      NULL);
+		} else {
+			dst_release(dst);
+		}
+		dst = NULL;
+	}
+
+out:
+	dst_release(dst);
+	fl6_sock_release(flowlabel);
+	if (!err)
+		return len;
+	/*
+	 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space.  Reporting
+	 * ENOBUFS might not be good (it's not tunable per se), but otherwise
+	 * we don't have a good statistic (IpOutDiscards but it can be too many
+	 * things).  We could add another new stat but at least for now that
+	 * seems like overkill.
+	 */
+	if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
+		UDP6_INC_STATS_USER(sock_net(sk),
+				UDP_MIB_SNDBUFERRORS, is_udplite);
+	}
+	return err;
+
+do_confirm:
+	dst_confirm(dst);
+	if (!(msg->msg_flags&MSG_PROBE) || len)
+		goto back_from_confirm;
+	err = 0;
+	goto out;
+}
+
+void udpv6_destroy_sock(struct sock *sk)
+{
+	struct udp_sock *up = udp_sk(sk);
+	lock_sock(sk);
+	udp_v6_flush_pending_frames(sk);
+	release_sock(sk);
+
+	if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
+		void (*encap_destroy)(struct sock *sk);
+		encap_destroy = ACCESS_ONCE(up->encap_destroy);
+		if (encap_destroy)
+			encap_destroy(sk);
+	}
+
+	inet6_destroy_sock(sk);
+}
+
+/*
+ *	Socket option code for UDP
+ */
+int udpv6_setsockopt(struct sock *sk, int level, int optname,
+		     char __user *optval, unsigned int optlen)
+{
+	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
+		return udp_lib_setsockopt(sk, level, optname, optval, optlen,
+					  udp_v6_push_pending_frames);
+	return ipv6_setsockopt(sk, level, optname, optval, optlen);
+}
+
+#ifdef CONFIG_COMPAT
+int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
+			    char __user *optval, unsigned int optlen)
+{
+	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
+		return udp_lib_setsockopt(sk, level, optname, optval, optlen,
+					  udp_v6_push_pending_frames);
+	return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
+}
+#endif
+
+int udpv6_getsockopt(struct sock *sk, int level, int optname,
+		     char __user *optval, int __user *optlen)
+{
+	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
+		return udp_lib_getsockopt(sk, level, optname, optval, optlen);
+	return ipv6_getsockopt(sk, level, optname, optval, optlen);
+}
+
+#ifdef CONFIG_COMPAT
+int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
+			    char __user *optval, int __user *optlen)
+{
+	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
+		return udp_lib_getsockopt(sk, level, optname, optval, optlen);
+	return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
+}
+#endif
+
+static const struct inet6_protocol udpv6_protocol = {
+	.handler	=	udpv6_rcv,
+	.err_handler	=	udpv6_err,
+	.flags		=	INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
+};
+
+/* ------------------------------------------------------------------------ */
+#ifdef CONFIG_PROC_FS
+int udp6_seq_show(struct seq_file *seq, void *v)
+{
+	if (v == SEQ_START_TOKEN) {
+		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
+	} else {
+		int bucket = ((struct udp_iter_state *)seq->private)->bucket;
+		struct inet_sock *inet = inet_sk(v);
+		__u16 srcp = ntohs(inet->inet_sport);
+		__u16 destp = ntohs(inet->inet_dport);
+		ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
+	}
+	return 0;
+}
+
+static const struct file_operations udp6_afinfo_seq_fops = {
+	.owner    = THIS_MODULE,
+	.open     = udp_seq_open,
+	.read     = seq_read,
+	.llseek   = seq_lseek,
+	.release  = seq_release_net
+};
+
+static struct udp_seq_afinfo udp6_seq_afinfo = {
+	.name		= "udp6",
+	.family		= AF_INET6,
+	.udp_table	= &udp_table,
+	.seq_fops	= &udp6_afinfo_seq_fops,
+	.seq_ops	= {
+		.show		= udp6_seq_show,
+	},
+};
+
+int __net_init udp6_proc_init(struct net *net)
+{
+	return udp_proc_register(net, &udp6_seq_afinfo);
+}
+
+void udp6_proc_exit(struct net *net) {
+	udp_proc_unregister(net, &udp6_seq_afinfo);
+}
+#endif /* CONFIG_PROC_FS */
+
+void udp_v6_clear_sk(struct sock *sk, int size)
+{
+	struct inet_sock *inet = inet_sk(sk);
+
+	/* we do not want to clear pinet6 field, because of RCU lookups */
+	sk_prot_clear_portaddr_nulls(sk, offsetof(struct inet_sock, pinet6));
+
+	size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6);
+	memset(&inet->pinet6 + 1, 0, size);
+}
+
+/* ------------------------------------------------------------------------ */
+
+struct proto udpv6_prot = {
+	.name		   = "UDPv6",
+	.owner		   = THIS_MODULE,
+	.close		   = udp_lib_close,
+	.connect	   = ip6_datagram_connect,
+	.disconnect	   = udp_disconnect,
+	.ioctl		   = udp_ioctl,
+	.destroy	   = udpv6_destroy_sock,
+	.setsockopt	   = udpv6_setsockopt,
+	.getsockopt	   = udpv6_getsockopt,
+	.sendmsg	   = udpv6_sendmsg,
+	.recvmsg	   = udpv6_recvmsg,
+	.backlog_rcv	   = __udpv6_queue_rcv_skb,
+	.hash		   = udp_lib_hash,
+	.unhash		   = udp_lib_unhash,
+	.rehash		   = udp_v6_rehash,
+	.get_port	   = udp_v6_get_port,
+	.memory_allocated  = &udp_memory_allocated,
+	.sysctl_mem	   = sysctl_udp_mem,
+	.sysctl_wmem	   = &sysctl_udp_wmem_min,
+	.sysctl_rmem	   = &sysctl_udp_rmem_min,
+	.obj_size	   = sizeof(struct udp6_sock),
+	.slab_flags	   = SLAB_DESTROY_BY_RCU,
+	.h.udp_table	   = &udp_table,
+#ifdef CONFIG_COMPAT
+	.compat_setsockopt = compat_udpv6_setsockopt,
+	.compat_getsockopt = compat_udpv6_getsockopt,
+#endif
+	.clear_sk	   = udp_v6_clear_sk,
+};
+
+static struct inet_protosw udpv6_protosw = {
+	.type =      SOCK_DGRAM,
+	.protocol =  IPPROTO_UDP,
+	.prot =      &udpv6_prot,
+	.ops =       &inet6_dgram_ops,
+	.flags =     INET_PROTOSW_PERMANENT,
+};
+
+int __init udpv6_init(void)
+{
+	int ret;
+
+	ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
+	if (ret)
+		goto out;
+
+	ret = inet6_register_protosw(&udpv6_protosw);
+	if (ret)
+		goto out_udpv6_protocol;
+out:
+	return ret;
+
+out_udpv6_protocol:
+	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
+	goto out;
+}
+
+void udpv6_exit(void)
+{
+	inet6_unregister_protosw(&udpv6_protosw);
+	inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
+}