Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1321 insertions, 0 deletions

diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
new file mode 100644
index 0000000000..4375bfa4f6
--- /dev/null
+++ b/net/ipv6/af_inet6.c
@@ -0,0 +1,1321 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *	PF_INET6 socket protocol family
+ *	Linux INET6 implementation
+ *
+ *	Authors:
+ *	Pedro Roque		<roque@di.fc.ul.pt>
+ *
+ *	Adapted from linux/net/ipv4/af_inet.c
+ *
+ *	Fixes:
+ *	piggy, Karl Knutson	:	Socket protocol table
+ *	Hideaki YOSHIFUJI	:	sin6_scope_id support
+ *	Arnaldo Melo		:	check proc_net_create return, cleanups
+ */
+
+#define pr_fmt(fmt) "IPv6: " fmt
+
+#include <linux/module.h>
+#include <linux/capability.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/kernel.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/proc_fs.h>
+#include <linux/stat.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/icmpv6.h>
+#include <linux/netfilter_ipv6.h>
+
+#include <net/ip.h>
+#include <net/ipv6.h>
+#include <net/udp.h>
+#include <net/udplite.h>
+#include <net/tcp.h>
+#include <net/ping.h>
+#include <net/protocol.h>
+#include <net/inet_common.h>
+#include <net/route.h>
+#include <net/transp_v6.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
+#include <net/ipv6_stubs.h>
+#include <net/ndisc.h>
+#ifdef CONFIG_IPV6_TUNNEL
+#include <net/ip6_tunnel.h>
+#endif
+#include <net/calipso.h>
+#include <net/seg6.h>
+#include <net/rpl.h>
+#include <net/compat.h>
+#include <net/xfrm.h>
+#include <net/ioam6.h>
+#include <net/rawv6.h>
+
+#include <linux/uaccess.h>
+#include <linux/mroute6.h>
+
+#include "ip6_offload.h"
+
+MODULE_AUTHOR("Cast of dozens");
+MODULE_DESCRIPTION("IPv6 protocol stack for Linux");
+MODULE_LICENSE("GPL");
+
+/* The inetsw6 table contains everything that inet6_create needs to
+ * build a new socket.
+ */
+static struct list_head inetsw6[SOCK_MAX];
+static DEFINE_SPINLOCK(inetsw6_lock);
+
+struct ipv6_params ipv6_defaults = {
+	.disable_ipv6 = 0,
+	.autoconf = 1,
+};
+
+static int disable_ipv6_mod;
+
+module_param_named(disable, disable_ipv6_mod, int, 0444);
+MODULE_PARM_DESC(disable, "Disable IPv6 module such that it is non-functional");
+
+module_param_named(disable_ipv6, ipv6_defaults.disable_ipv6, int, 0444);
+MODULE_PARM_DESC(disable_ipv6, "Disable IPv6 on all interfaces");
+
+module_param_named(autoconf, ipv6_defaults.autoconf, int, 0444);
+MODULE_PARM_DESC(autoconf, "Enable IPv6 address autoconfiguration on all interfaces");
+
+bool ipv6_mod_enabled(void)
+{
+	return disable_ipv6_mod == 0;
+}
+EXPORT_SYMBOL_GPL(ipv6_mod_enabled);
+
+static struct ipv6_pinfo *inet6_sk_generic(struct sock *sk)
+{
+	const int offset = sk->sk_prot->ipv6_pinfo_offset;
+
+	return (struct ipv6_pinfo *)(((u8 *)sk) + offset);
+}
+
+void inet6_sock_destruct(struct sock *sk)
+{
+	inet6_cleanup_sock(sk);
+	inet_sock_destruct(sk);
+}
+EXPORT_SYMBOL_GPL(inet6_sock_destruct);
+
+static int inet6_create(struct net *net, struct socket *sock, int protocol,
+			int kern)
+{
+	struct inet_sock *inet;
+	struct ipv6_pinfo *np;
+	struct sock *sk;
+	struct inet_protosw *answer;
+	struct proto *answer_prot;
+	unsigned char answer_flags;
+	int try_loading_module = 0;
+	int err;
+
+	if (protocol < 0 || protocol >= IPPROTO_MAX)
+		return -EINVAL;
+
+	/* Look for the requested type/protocol pair. */
+lookup_protocol:
+	err = -ESOCKTNOSUPPORT;
+	rcu_read_lock();
+	list_for_each_entry_rcu(answer, &inetsw6[sock->type], list) {
+
+		err = 0;
+		/* Check the non-wild match. */
+		if (protocol == answer->protocol) {
+			if (protocol != IPPROTO_IP)
+				break;
+		} else {
+			/* Check for the two wild cases. */
+			if (IPPROTO_IP == protocol) {
+				protocol = answer->protocol;
+				break;
+			}
+			if (IPPROTO_IP == answer->protocol)
+				break;
+		}
+		err = -EPROTONOSUPPORT;
+	}
+
+	if (err) {
+		if (try_loading_module < 2) {
+			rcu_read_unlock();
+			/*
+			 * Be more specific, e.g. net-pf-10-proto-132-type-1
+			 * (net-pf-PF_INET6-proto-IPPROTO_SCTP-type-SOCK_STREAM)
+			 */
+			if (++try_loading_module == 1)
+				request_module("net-pf-%d-proto-%d-type-%d",
+						PF_INET6, protocol, sock->type);
+			/*
+			 * Fall back to generic, e.g. net-pf-10-proto-132
+			 * (net-pf-PF_INET6-proto-IPPROTO_SCTP)
+			 */
+			else
+				request_module("net-pf-%d-proto-%d",
+						PF_INET6, protocol);
+			goto lookup_protocol;
+		} else
+			goto out_rcu_unlock;
+	}
+
+	err = -EPERM;
+	if (sock->type == SOCK_RAW && !kern &&
+	    !ns_capable(net->user_ns, CAP_NET_RAW))
+		goto out_rcu_unlock;
+
+	sock->ops = answer->ops;
+	answer_prot = answer->prot;
+	answer_flags = answer->flags;
+	rcu_read_unlock();
+
+	WARN_ON(!answer_prot->slab);
+
+	err = -ENOBUFS;
+	sk = sk_alloc(net, PF_INET6, GFP_KERNEL, answer_prot, kern);
+	if (!sk)
+		goto out;
+
+	sock_init_data(sock, sk);
+
+	err = 0;
+	if (INET_PROTOSW_REUSE & answer_flags)
+		sk->sk_reuse = SK_CAN_REUSE;
+
+	if (INET_PROTOSW_ICSK & answer_flags)
+		inet_init_csk_locks(sk);
+
+	inet = inet_sk(sk);
+	inet_assign_bit(IS_ICSK, sk, INET_PROTOSW_ICSK & answer_flags);
+
+	if (SOCK_RAW == sock->type) {
+		inet->inet_num = protocol;
+		if (IPPROTO_RAW == protocol)
+			inet_set_bit(HDRINCL, sk);
+	}
+
+	sk->sk_destruct		= inet6_sock_destruct;
+	sk->sk_family		= PF_INET6;
+	sk->sk_protocol		= protocol;
+
+	sk->sk_backlog_rcv	= answer->prot->backlog_rcv;
+
+	inet_sk(sk)->pinet6 = np = inet6_sk_generic(sk);
+	np->hop_limit	= -1;
+	np->mcast_hops	= IPV6_DEFAULT_MCASTHOPS;
+	np->mc_loop	= 1;
+	np->mc_all	= 1;
+	np->pmtudisc	= IPV6_PMTUDISC_WANT;
+	np->repflow	= net->ipv6.sysctl.flowlabel_reflect & FLOWLABEL_REFLECT_ESTABLISHED;
+	sk->sk_ipv6only	= net->ipv6.sysctl.bindv6only;
+	sk->sk_txrehash = READ_ONCE(net->core.sysctl_txrehash);
+
+	/* Init the ipv4 part of the socket since we can have sockets
+	 * using v6 API for ipv4.
+	 */
+	inet->uc_ttl	= -1;
+
+	inet_set_bit(MC_LOOP, sk);
+	inet->mc_ttl	= 1;
+	inet->mc_index	= 0;
+	RCU_INIT_POINTER(inet->mc_list, NULL);
+	inet->rcv_tos	= 0;
+
+	if (READ_ONCE(net->ipv4.sysctl_ip_no_pmtu_disc))
+		inet->pmtudisc = IP_PMTUDISC_DONT;
+	else
+		inet->pmtudisc = IP_PMTUDISC_WANT;
+
+	if (inet->inet_num) {
+		/* It assumes that any protocol which allows
+		 * the user to assign a number at socket
+		 * creation time automatically shares.
+		 */
+		inet->inet_sport = htons(inet->inet_num);
+		err = sk->sk_prot->hash(sk);
+		if (err) {
+			sk_common_release(sk);
+			goto out;
+		}
+	}
+	if (sk->sk_prot->init) {
+		err = sk->sk_prot->init(sk);
+		if (err) {
+			sk_common_release(sk);
+			goto out;
+		}
+	}
+
+	if (!kern) {
+		err = BPF_CGROUP_RUN_PROG_INET_SOCK(sk);
+		if (err) {
+			sk_common_release(sk);
+			goto out;
+		}
+	}
+out:
+	return err;
+out_rcu_unlock:
+	rcu_read_unlock();
+	goto out;
+}
+
+static int __inet6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len,
+			u32 flags)
+{
+	struct sockaddr_in6 *addr = (struct sockaddr_in6 *)uaddr;
+	struct inet_sock *inet = inet_sk(sk);
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct net *net = sock_net(sk);
+	__be32 v4addr = 0;
+	unsigned short snum;
+	bool saved_ipv6only;
+	int addr_type = 0;
+	int err = 0;
+
+	if (addr->sin6_family != AF_INET6)
+		return -EAFNOSUPPORT;
+
+	addr_type = ipv6_addr_type(&addr->sin6_addr);
+	if ((addr_type & IPV6_ADDR_MULTICAST) && sk->sk_type == SOCK_STREAM)
+		return -EINVAL;
+
+	snum = ntohs(addr->sin6_port);
+	if (!(flags & BIND_NO_CAP_NET_BIND_SERVICE) &&
+	    snum && inet_port_requires_bind_service(net, snum) &&
+	    !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
+		return -EACCES;
+
+	if (flags & BIND_WITH_LOCK)
+		lock_sock(sk);
+
+	/* Check these errors (active socket, double bind). */
+	if (sk->sk_state != TCP_CLOSE || inet->inet_num) {
+		err = -EINVAL;
+		goto out;
+	}
+
+	/* Check if the address belongs to the host. */
+	if (addr_type == IPV6_ADDR_MAPPED) {
+		struct net_device *dev = NULL;
+		int chk_addr_ret;
+
+		/* Binding to v4-mapped address on a v6-only socket
+		 * makes no sense
+		 */
+		if (ipv6_only_sock(sk)) {
+			err = -EINVAL;
+			goto out;
+		}
+
+		rcu_read_lock();
+		if (sk->sk_bound_dev_if) {
+			dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
+			if (!dev) {
+				err = -ENODEV;
+				goto out_unlock;
+			}
+		}
+
+		/* Reproduce AF_INET checks to make the bindings consistent */
+		v4addr = addr->sin6_addr.s6_addr32[3];
+		chk_addr_ret = inet_addr_type_dev_table(net, dev, v4addr);
+		rcu_read_unlock();
+
+		if (!inet_addr_valid_or_nonlocal(net, inet, v4addr,
+						 chk_addr_ret)) {
+			err = -EADDRNOTAVAIL;
+			goto out;
+		}
+	} else {
+		if (addr_type != IPV6_ADDR_ANY) {
+			struct net_device *dev = NULL;
+
+			rcu_read_lock();
+			if (__ipv6_addr_needs_scope_id(addr_type)) {
+				if (addr_len >= sizeof(struct sockaddr_in6) &&
+				    addr->sin6_scope_id) {
+					/* Override any existing binding, if another one
+					 * is supplied by user.
+					 */
+					sk->sk_bound_dev_if = addr->sin6_scope_id;
+				}
+
+				/* Binding to link-local address requires an interface */
+				if (!sk->sk_bound_dev_if) {
+					err = -EINVAL;
+					goto out_unlock;
+				}
+			}
+
+			if (sk->sk_bound_dev_if) {
+				dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
+				if (!dev) {
+					err = -ENODEV;
+					goto out_unlock;
+				}
+			}
+
+			/* ipv4 addr of the socket is invalid.  Only the
+			 * unspecified and mapped address have a v4 equivalent.
+			 */
+			v4addr = LOOPBACK4_IPV6;
+			if (!(addr_type & IPV6_ADDR_MULTICAST))	{
+				if (!ipv6_can_nonlocal_bind(net, inet) &&
+				    !ipv6_chk_addr(net, &addr->sin6_addr,
+						   dev, 0)) {
+					err = -EADDRNOTAVAIL;
+					goto out_unlock;
+				}
+			}
+			rcu_read_unlock();
+		}
+	}
+
+	inet->inet_rcv_saddr = v4addr;
+	inet->inet_saddr = v4addr;
+
+	sk->sk_v6_rcv_saddr = addr->sin6_addr;
+
+	if (!(addr_type & IPV6_ADDR_MULTICAST))
+		np->saddr = addr->sin6_addr;
+
+	saved_ipv6only = sk->sk_ipv6only;
+	if (addr_type != IPV6_ADDR_ANY && addr_type != IPV6_ADDR_MAPPED)
+		sk->sk_ipv6only = 1;
+
+	/* Make sure we are allowed to bind here. */
+	if (snum || !(inet_test_bit(BIND_ADDRESS_NO_PORT, sk) ||
+		      (flags & BIND_FORCE_ADDRESS_NO_PORT))) {
+		err = sk->sk_prot->get_port(sk, snum);
+		if (err) {
+			sk->sk_ipv6only = saved_ipv6only;
+			inet_reset_saddr(sk);
+			goto out;
+		}
+		if (!(flags & BIND_FROM_BPF)) {
+			err = BPF_CGROUP_RUN_PROG_INET6_POST_BIND(sk);
+			if (err) {
+				sk->sk_ipv6only = saved_ipv6only;
+				inet_reset_saddr(sk);
+				if (sk->sk_prot->put_port)
+					sk->sk_prot->put_port(sk);
+				goto out;
+			}
+		}
+	}
+
+	if (addr_type != IPV6_ADDR_ANY)
+		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
+	if (snum)
+		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
+	inet->inet_sport = htons(inet->inet_num);
+	inet->inet_dport = 0;
+	inet->inet_daddr = 0;
+out:
+	if (flags & BIND_WITH_LOCK)
+		release_sock(sk);
+	return err;
+out_unlock:
+	rcu_read_unlock();
+	goto out;
+}
+
+int inet6_bind_sk(struct sock *sk, struct sockaddr *uaddr, int addr_len)
+{
+	u32 flags = BIND_WITH_LOCK;
+	const struct proto *prot;
+	int err = 0;
+
+	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
+	prot = READ_ONCE(sk->sk_prot);
+	/* If the socket has its own bind function then use it. */
+	if (prot->bind)
+		return prot->bind(sk, uaddr, addr_len);
+
+	if (addr_len < SIN6_LEN_RFC2133)
+		return -EINVAL;
+
+	/* BPF prog is run before any checks are done so that if the prog
+	 * changes context in a wrong way it will be caught.
+	 */
+	err = BPF_CGROUP_RUN_PROG_INET_BIND_LOCK(sk, uaddr, &addr_len,
+						 CGROUP_INET6_BIND, &flags);
+	if (err)
+		return err;
+
+	return __inet6_bind(sk, uaddr, addr_len, flags);
+}
+
+/* bind for INET6 API */
+int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
+{
+	return inet6_bind_sk(sock->sk, uaddr, addr_len);
+}
+EXPORT_SYMBOL(inet6_bind);
+
+int inet6_release(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+
+	if (!sk)
+		return -EINVAL;
+
+	/* Free mc lists */
+	ipv6_sock_mc_close(sk);
+
+	/* Free ac lists */
+	ipv6_sock_ac_close(sk);
+
+	return inet_release(sock);
+}
+EXPORT_SYMBOL(inet6_release);
+
+void inet6_cleanup_sock(struct sock *sk)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct sk_buff *skb;
+	struct ipv6_txoptions *opt;
+
+	/* Release rx options */
+
+	skb = xchg(&np->pktoptions, NULL);
+	kfree_skb(skb);
+
+	skb = xchg(&np->rxpmtu, NULL);
+	kfree_skb(skb);
+
+	/* Free flowlabels */
+	fl6_free_socklist(sk);
+
+	/* Free tx options */
+
+	opt = xchg((__force struct ipv6_txoptions **)&np->opt, NULL);
+	if (opt) {
+		atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
+		txopt_put(opt);
+	}
+}
+EXPORT_SYMBOL_GPL(inet6_cleanup_sock);
+
+/*
+ *	This does both peername and sockname.
+ */
+int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
+		  int peer)
+{
+	struct sockaddr_in6 *sin = (struct sockaddr_in6 *)uaddr;
+	int sin_addr_len = sizeof(*sin);
+	struct sock *sk = sock->sk;
+	struct inet_sock *inet = inet_sk(sk);
+	struct ipv6_pinfo *np = inet6_sk(sk);
+
+	sin->sin6_family = AF_INET6;
+	sin->sin6_flowinfo = 0;
+	sin->sin6_scope_id = 0;
+	lock_sock(sk);
+	if (peer) {
+		if (!inet->inet_dport ||
+		    (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
+		    peer == 1)) {
+			release_sock(sk);
+			return -ENOTCONN;
+		}
+		sin->sin6_port = inet->inet_dport;
+		sin->sin6_addr = sk->sk_v6_daddr;
+		if (np->sndflow)
+			sin->sin6_flowinfo = np->flow_label;
+		BPF_CGROUP_RUN_SA_PROG(sk, (struct sockaddr *)sin, &sin_addr_len,
+				       CGROUP_INET6_GETPEERNAME);
+	} else {
+		if (ipv6_addr_any(&sk->sk_v6_rcv_saddr))
+			sin->sin6_addr = np->saddr;
+		else
+			sin->sin6_addr = sk->sk_v6_rcv_saddr;
+		sin->sin6_port = inet->inet_sport;
+		BPF_CGROUP_RUN_SA_PROG(sk, (struct sockaddr *)sin, &sin_addr_len,
+				       CGROUP_INET6_GETSOCKNAME);
+	}
+	sin->sin6_scope_id = ipv6_iface_scope_id(&sin->sin6_addr,
+						 sk->sk_bound_dev_if);
+	release_sock(sk);
+	return sin_addr_len;
+}
+EXPORT_SYMBOL(inet6_getname);
+
+int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+	void __user *argp = (void __user *)arg;
+	struct sock *sk = sock->sk;
+	struct net *net = sock_net(sk);
+	const struct proto *prot;
+
+	switch (cmd) {
+	case SIOCADDRT:
+	case SIOCDELRT: {
+		struct in6_rtmsg rtmsg;
+
+		if (copy_from_user(&rtmsg, argp, sizeof(rtmsg)))
+			return -EFAULT;
+		return ipv6_route_ioctl(net, cmd, &rtmsg);
+	}
+	case SIOCSIFADDR:
+		return addrconf_add_ifaddr(net, argp);
+	case SIOCDIFADDR:
+		return addrconf_del_ifaddr(net, argp);
+	case SIOCSIFDSTADDR:
+		return addrconf_set_dstaddr(net, argp);
+	default:
+		/* IPV6_ADDRFORM can change sk->sk_prot under us. */
+		prot = READ_ONCE(sk->sk_prot);
+		if (!prot->ioctl)
+			return -ENOIOCTLCMD;
+		return sk_ioctl(sk, cmd, (void __user *)arg);
+	}
+	/*NOTREACHED*/
+	return 0;
+}
+EXPORT_SYMBOL(inet6_ioctl);
+
+#ifdef CONFIG_COMPAT
+struct compat_in6_rtmsg {
+	struct in6_addr		rtmsg_dst;
+	struct in6_addr		rtmsg_src;
+	struct in6_addr		rtmsg_gateway;
+	u32			rtmsg_type;
+	u16			rtmsg_dst_len;
+	u16			rtmsg_src_len;
+	u32			rtmsg_metric;
+	u32			rtmsg_info;
+	u32			rtmsg_flags;
+	s32			rtmsg_ifindex;
+};
+
+static int inet6_compat_routing_ioctl(struct sock *sk, unsigned int cmd,
+		struct compat_in6_rtmsg __user *ur)
+{
+	struct in6_rtmsg rt;
+
+	if (copy_from_user(&rt.rtmsg_dst, &ur->rtmsg_dst,
+			3 * sizeof(struct in6_addr)) ||
+	    get_user(rt.rtmsg_type, &ur->rtmsg_type) ||
+	    get_user(rt.rtmsg_dst_len, &ur->rtmsg_dst_len) ||
+	    get_user(rt.rtmsg_src_len, &ur->rtmsg_src_len) ||
+	    get_user(rt.rtmsg_metric, &ur->rtmsg_metric) ||
+	    get_user(rt.rtmsg_info, &ur->rtmsg_info) ||
+	    get_user(rt.rtmsg_flags, &ur->rtmsg_flags) ||
+	    get_user(rt.rtmsg_ifindex, &ur->rtmsg_ifindex))
+		return -EFAULT;
+
+
+	return ipv6_route_ioctl(sock_net(sk), cmd, &rt);
+}
+
+int inet6_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+	void __user *argp = compat_ptr(arg);
+	struct sock *sk = sock->sk;
+
+	switch (cmd) {
+	case SIOCADDRT:
+	case SIOCDELRT:
+		return inet6_compat_routing_ioctl(sk, cmd, argp);
+	default:
+		return -ENOIOCTLCMD;
+	}
+}
+EXPORT_SYMBOL_GPL(inet6_compat_ioctl);
+#endif /* CONFIG_COMPAT */
+
+INDIRECT_CALLABLE_DECLARE(int udpv6_sendmsg(struct sock *, struct msghdr *,
+					    size_t));
+int inet6_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
+{
+	struct sock *sk = sock->sk;
+	const struct proto *prot;
+
+	if (unlikely(inet_send_prepare(sk)))
+		return -EAGAIN;
+
+	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
+	prot = READ_ONCE(sk->sk_prot);
+	return INDIRECT_CALL_2(prot->sendmsg, tcp_sendmsg, udpv6_sendmsg,
+			       sk, msg, size);
+}
+
+INDIRECT_CALLABLE_DECLARE(int udpv6_recvmsg(struct sock *, struct msghdr *,
+					    size_t, int, int *));
+int inet6_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
+		  int flags)
+{
+	struct sock *sk = sock->sk;
+	const struct proto *prot;
+	int addr_len = 0;
+	int err;
+
+	if (likely(!(flags & MSG_ERRQUEUE)))
+		sock_rps_record_flow(sk);
+
+	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
+	prot = READ_ONCE(sk->sk_prot);
+	err = INDIRECT_CALL_2(prot->recvmsg, tcp_recvmsg, udpv6_recvmsg,
+			      sk, msg, size, flags, &addr_len);
+	if (err >= 0)
+		msg->msg_namelen = addr_len;
+	return err;
+}
+
+const struct proto_ops inet6_stream_ops = {
+	.family		   = PF_INET6,
+	.owner		   = THIS_MODULE,
+	.release	   = inet6_release,
+	.bind		   = inet6_bind,
+	.connect	   = inet_stream_connect,	/* ok		*/
+	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
+	.accept		   = inet_accept,		/* ok		*/
+	.getname	   = inet6_getname,
+	.poll		   = tcp_poll,			/* ok		*/
+	.ioctl		   = inet6_ioctl,		/* must change  */
+	.gettstamp	   = sock_gettstamp,
+	.listen		   = inet_listen,		/* ok		*/
+	.shutdown	   = inet_shutdown,		/* ok		*/
+	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
+	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
+	.sendmsg	   = inet6_sendmsg,		/* retpoline's sake */
+	.recvmsg	   = inet6_recvmsg,		/* retpoline's sake */
+#ifdef CONFIG_MMU
+	.mmap		   = tcp_mmap,
+#endif
+	.splice_eof	   = inet_splice_eof,
+	.sendmsg_locked    = tcp_sendmsg_locked,
+	.splice_read	   = tcp_splice_read,
+	.read_sock	   = tcp_read_sock,
+	.read_skb	   = tcp_read_skb,
+	.peek_len	   = tcp_peek_len,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	   = inet6_compat_ioctl,
+#endif
+	.set_rcvlowat	   = tcp_set_rcvlowat,
+};
+
+const struct proto_ops inet6_dgram_ops = {
+	.family		   = PF_INET6,
+	.owner		   = THIS_MODULE,
+	.release	   = inet6_release,
+	.bind		   = inet6_bind,
+	.connect	   = inet_dgram_connect,	/* ok		*/
+	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
+	.accept		   = sock_no_accept,		/* a do nothing	*/
+	.getname	   = inet6_getname,
+	.poll		   = udp_poll,			/* ok		*/
+	.ioctl		   = inet6_ioctl,		/* must change  */
+	.gettstamp	   = sock_gettstamp,
+	.listen		   = sock_no_listen,		/* ok		*/
+	.shutdown	   = inet_shutdown,		/* ok		*/
+	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
+	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
+	.sendmsg	   = inet6_sendmsg,		/* retpoline's sake */
+	.recvmsg	   = inet6_recvmsg,		/* retpoline's sake */
+	.read_skb	   = udp_read_skb,
+	.mmap		   = sock_no_mmap,
+	.set_peek_off	   = sk_set_peek_off,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	   = inet6_compat_ioctl,
+#endif
+};
+
+static const struct net_proto_family inet6_family_ops = {
+	.family = PF_INET6,
+	.create = inet6_create,
+	.owner	= THIS_MODULE,
+};
+
+int inet6_register_protosw(struct inet_protosw *p)
+{
+	struct list_head *lh;
+	struct inet_protosw *answer;
+	struct list_head *last_perm;
+	int protocol = p->protocol;
+	int ret;
+
+	spin_lock_bh(&inetsw6_lock);
+
+	ret = -EINVAL;
+	if (p->type >= SOCK_MAX)
+		goto out_illegal;
+
+	/* If we are trying to override a permanent protocol, bail. */
+	answer = NULL;
+	ret = -EPERM;
+	last_perm = &inetsw6[p->type];
+	list_for_each(lh, &inetsw6[p->type]) {
+		answer = list_entry(lh, struct inet_protosw, list);
+
+		/* Check only the non-wild match. */
+		if (INET_PROTOSW_PERMANENT & answer->flags) {
+			if (protocol == answer->protocol)
+				break;
+			last_perm = lh;
+		}
+
+		answer = NULL;
+	}
+	if (answer)
+		goto out_permanent;
+
+	/* Add the new entry after the last permanent entry if any, so that
+	 * the new entry does not override a permanent entry when matched with
+	 * a wild-card protocol. But it is allowed to override any existing
+	 * non-permanent entry.  This means that when we remove this entry, the
+	 * system automatically returns to the old behavior.
+	 */
+	list_add_rcu(&p->list, last_perm);
+	ret = 0;
+out:
+	spin_unlock_bh(&inetsw6_lock);
+	return ret;
+
+out_permanent:
+	pr_err("Attempt to override permanent protocol %d\n", protocol);
+	goto out;
+
+out_illegal:
+	pr_err("Ignoring attempt to register invalid socket type %d\n",
+	       p->type);
+	goto out;
+}
+EXPORT_SYMBOL(inet6_register_protosw);
+
+void
+inet6_unregister_protosw(struct inet_protosw *p)
+{
+	if (INET_PROTOSW_PERMANENT & p->flags) {
+		pr_err("Attempt to unregister permanent protocol %d\n",
+		       p->protocol);
+	} else {
+		spin_lock_bh(&inetsw6_lock);
+		list_del_rcu(&p->list);
+		spin_unlock_bh(&inetsw6_lock);
+
+		synchronize_net();
+	}
+}
+EXPORT_SYMBOL(inet6_unregister_protosw);
+
+int inet6_sk_rebuild_header(struct sock *sk)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct dst_entry *dst;
+
+	dst = __sk_dst_check(sk, np->dst_cookie);
+
+	if (!dst) {
+		struct inet_sock *inet = inet_sk(sk);
+		struct in6_addr *final_p, final;
+		struct flowi6 fl6;
+
+		memset(&fl6, 0, sizeof(fl6));
+		fl6.flowi6_proto = sk->sk_protocol;
+		fl6.daddr = sk->sk_v6_daddr;
+		fl6.saddr = np->saddr;
+		fl6.flowlabel = np->flow_label;
+		fl6.flowi6_oif = sk->sk_bound_dev_if;
+		fl6.flowi6_mark = sk->sk_mark;
+		fl6.fl6_dport = inet->inet_dport;
+		fl6.fl6_sport = inet->inet_sport;
+		fl6.flowi6_uid = sk->sk_uid;
+		security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
+
+		rcu_read_lock();
+		final_p = fl6_update_dst(&fl6, rcu_dereference(np->opt),
+					 &final);
+		rcu_read_unlock();
+
+		dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
+		if (IS_ERR(dst)) {
+			sk->sk_route_caps = 0;
+			WRITE_ONCE(sk->sk_err_soft, -PTR_ERR(dst));
+			return PTR_ERR(dst);
+		}
+
+		ip6_dst_store(sk, dst, NULL, NULL);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
+
+bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
+		       const struct inet6_skb_parm *opt)
+{
+	const struct ipv6_pinfo *np = inet6_sk(sk);
+
+	if (np->rxopt.all) {
+		if (((opt->flags & IP6SKB_HOPBYHOP) &&
+		     (np->rxopt.bits.hopopts || np->rxopt.bits.ohopopts)) ||
+		    (ip6_flowinfo((struct ipv6hdr *) skb_network_header(skb)) &&
+		     np->rxopt.bits.rxflow) ||
+		    (opt->srcrt && (np->rxopt.bits.srcrt ||
+		     np->rxopt.bits.osrcrt)) ||
+		    ((opt->dst1 || opt->dst0) &&
+		     (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
+			return true;
+	}
+	return false;
+}
+EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
+
+static struct packet_type ipv6_packet_type __read_mostly = {
+	.type = cpu_to_be16(ETH_P_IPV6),
+	.func = ipv6_rcv,
+	.list_func = ipv6_list_rcv,
+};
+
+static int __init ipv6_packet_init(void)
+{
+	dev_add_pack(&ipv6_packet_type);
+	return 0;
+}
+
+static void ipv6_packet_cleanup(void)
+{
+	dev_remove_pack(&ipv6_packet_type);
+}
+
+static int __net_init ipv6_init_mibs(struct net *net)
+{
+	int i;
+
+	net->mib.udp_stats_in6 = alloc_percpu(struct udp_mib);
+	if (!net->mib.udp_stats_in6)
+		return -ENOMEM;
+	net->mib.udplite_stats_in6 = alloc_percpu(struct udp_mib);
+	if (!net->mib.udplite_stats_in6)
+		goto err_udplite_mib;
+	net->mib.ipv6_statistics = alloc_percpu(struct ipstats_mib);
+	if (!net->mib.ipv6_statistics)
+		goto err_ip_mib;
+
+	for_each_possible_cpu(i) {
+		struct ipstats_mib *af_inet6_stats;
+		af_inet6_stats = per_cpu_ptr(net->mib.ipv6_statistics, i);
+		u64_stats_init(&af_inet6_stats->syncp);
+	}
+
+
+	net->mib.icmpv6_statistics = alloc_percpu(struct icmpv6_mib);
+	if (!net->mib.icmpv6_statistics)
+		goto err_icmp_mib;
+	net->mib.icmpv6msg_statistics = kzalloc(sizeof(struct icmpv6msg_mib),
+						GFP_KERNEL);
+	if (!net->mib.icmpv6msg_statistics)
+		goto err_icmpmsg_mib;
+	return 0;
+
+err_icmpmsg_mib:
+	free_percpu(net->mib.icmpv6_statistics);
+err_icmp_mib:
+	free_percpu(net->mib.ipv6_statistics);
+err_ip_mib:
+	free_percpu(net->mib.udplite_stats_in6);
+err_udplite_mib:
+	free_percpu(net->mib.udp_stats_in6);
+	return -ENOMEM;
+}
+
+static void ipv6_cleanup_mibs(struct net *net)
+{
+	free_percpu(net->mib.udp_stats_in6);
+	free_percpu(net->mib.udplite_stats_in6);
+	free_percpu(net->mib.ipv6_statistics);
+	free_percpu(net->mib.icmpv6_statistics);
+	kfree(net->mib.icmpv6msg_statistics);
+}
+
+static int __net_init inet6_net_init(struct net *net)
+{
+	int err = 0;
+
+	net->ipv6.sysctl.bindv6only = 0;
+	net->ipv6.sysctl.icmpv6_time = 1*HZ;
+	net->ipv6.sysctl.icmpv6_echo_ignore_all = 0;
+	net->ipv6.sysctl.icmpv6_echo_ignore_multicast = 0;
+	net->ipv6.sysctl.icmpv6_echo_ignore_anycast = 0;
+	net->ipv6.sysctl.icmpv6_error_anycast_as_unicast = 0;
+
+	/* By default, rate limit error messages.
+	 * Except for pmtu discovery, it would break it.
+	 * proc_do_large_bitmap needs pointer to the bitmap.
+	 */
+	bitmap_set(net->ipv6.sysctl.icmpv6_ratemask, 0, ICMPV6_ERRMSG_MAX + 1);
+	bitmap_clear(net->ipv6.sysctl.icmpv6_ratemask, ICMPV6_PKT_TOOBIG, 1);
+	net->ipv6.sysctl.icmpv6_ratemask_ptr = net->ipv6.sysctl.icmpv6_ratemask;
+
+	net->ipv6.sysctl.flowlabel_consistency = 1;
+	net->ipv6.sysctl.auto_flowlabels = IP6_DEFAULT_AUTO_FLOW_LABELS;
+	net->ipv6.sysctl.idgen_retries = 3;
+	net->ipv6.sysctl.idgen_delay = 1 * HZ;
+	net->ipv6.sysctl.flowlabel_state_ranges = 0;
+	net->ipv6.sysctl.max_dst_opts_cnt = IP6_DEFAULT_MAX_DST_OPTS_CNT;
+	net->ipv6.sysctl.max_hbh_opts_cnt = IP6_DEFAULT_MAX_HBH_OPTS_CNT;
+	net->ipv6.sysctl.max_dst_opts_len = IP6_DEFAULT_MAX_DST_OPTS_LEN;
+	net->ipv6.sysctl.max_hbh_opts_len = IP6_DEFAULT_MAX_HBH_OPTS_LEN;
+	net->ipv6.sysctl.fib_notify_on_flag_change = 0;
+	atomic_set(&net->ipv6.fib6_sernum, 1);
+
+	net->ipv6.sysctl.ioam6_id = IOAM6_DEFAULT_ID;
+	net->ipv6.sysctl.ioam6_id_wide = IOAM6_DEFAULT_ID_WIDE;
+
+	err = ipv6_init_mibs(net);
+	if (err)
+		return err;
+#ifdef CONFIG_PROC_FS
+	err = udp6_proc_init(net);
+	if (err)
+		goto out;
+	err = tcp6_proc_init(net);
+	if (err)
+		goto proc_tcp6_fail;
+	err = ac6_proc_init(net);
+	if (err)
+		goto proc_ac6_fail;
+#endif
+	return err;
+
+#ifdef CONFIG_PROC_FS
+proc_ac6_fail:
+	tcp6_proc_exit(net);
+proc_tcp6_fail:
+	udp6_proc_exit(net);
+out:
+	ipv6_cleanup_mibs(net);
+	return err;
+#endif
+}
+
+static void __net_exit inet6_net_exit(struct net *net)
+{
+#ifdef CONFIG_PROC_FS
+	udp6_proc_exit(net);
+	tcp6_proc_exit(net);
+	ac6_proc_exit(net);
+#endif
+	ipv6_cleanup_mibs(net);
+}
+
+static struct pernet_operations inet6_net_ops = {
+	.init = inet6_net_init,
+	.exit = inet6_net_exit,
+};
+
+static int ipv6_route_input(struct sk_buff *skb)
+{
+	ip6_route_input(skb);
+	return skb_dst(skb)->error;
+}
+
+static const struct ipv6_stub ipv6_stub_impl = {
+	.ipv6_sock_mc_join = ipv6_sock_mc_join,
+	.ipv6_sock_mc_drop = ipv6_sock_mc_drop,
+	.ipv6_dst_lookup_flow = ip6_dst_lookup_flow,
+	.ipv6_route_input  = ipv6_route_input,
+	.fib6_get_table	   = fib6_get_table,
+	.fib6_table_lookup = fib6_table_lookup,
+	.fib6_lookup       = fib6_lookup,
+	.fib6_select_path  = fib6_select_path,
+	.ip6_mtu_from_fib6 = ip6_mtu_from_fib6,
+	.fib6_nh_init	   = fib6_nh_init,
+	.fib6_nh_release   = fib6_nh_release,
+	.fib6_nh_release_dsts = fib6_nh_release_dsts,
+	.fib6_update_sernum = fib6_update_sernum_stub,
+	.fib6_rt_update	   = fib6_rt_update,
+	.ip6_del_rt	   = ip6_del_rt,
+	.udpv6_encap_enable = udpv6_encap_enable,
+	.ndisc_send_na = ndisc_send_na,
+#if IS_ENABLED(CONFIG_XFRM)
+	.xfrm6_local_rxpmtu = xfrm6_local_rxpmtu,
+	.xfrm6_udp_encap_rcv = xfrm6_udp_encap_rcv,
+	.xfrm6_rcv_encap = xfrm6_rcv_encap,
+#endif
+	.nd_tbl	= &nd_tbl,
+	.ipv6_fragment = ip6_fragment,
+	.ipv6_dev_find = ipv6_dev_find,
+};
+
+static const struct ipv6_bpf_stub ipv6_bpf_stub_impl = {
+	.inet6_bind = __inet6_bind,
+	.udp6_lib_lookup = __udp6_lib_lookup,
+	.ipv6_setsockopt = do_ipv6_setsockopt,
+	.ipv6_getsockopt = do_ipv6_getsockopt,
+};
+
+static int __init inet6_init(void)
+{
+	struct list_head *r;
+	int err = 0;
+
+	sock_skb_cb_check_size(sizeof(struct inet6_skb_parm));
+
+	/* Register the socket-side information for inet6_create.  */
+	for (r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
+		INIT_LIST_HEAD(r);
+
+	raw_hashinfo_init(&raw_v6_hashinfo);
+
+	if (disable_ipv6_mod) {
+		pr_info("Loaded, but administratively disabled, reboot required to enable\n");
+		goto out;
+	}
+
+	err = proto_register(&tcpv6_prot, 1);
+	if (err)
+		goto out;
+
+	err = proto_register(&udpv6_prot, 1);
+	if (err)
+		goto out_unregister_tcp_proto;
+
+	err = proto_register(&udplitev6_prot, 1);
+	if (err)
+		goto out_unregister_udp_proto;
+
+	err = proto_register(&rawv6_prot, 1);
+	if (err)
+		goto out_unregister_udplite_proto;
+
+	err = proto_register(&pingv6_prot, 1);
+	if (err)
+		goto out_unregister_raw_proto;
+
+	/* We MUST register RAW sockets before we create the ICMP6,
+	 * IGMP6, or NDISC control sockets.
+	 */
+	err = rawv6_init();
+	if (err)
+		goto out_unregister_ping_proto;
+
+	/* Register the family here so that the init calls below will
+	 * be able to create sockets. (?? is this dangerous ??)
+	 */
+	err = sock_register(&inet6_family_ops);
+	if (err)
+		goto out_sock_register_fail;
+
+	/*
+	 *	ipngwg API draft makes clear that the correct semantics
+	 *	for TCP and UDP is to consider one TCP and UDP instance
+	 *	in a host available by both INET and INET6 APIs and
+	 *	able to communicate via both network protocols.
+	 */
+
+	err = register_pernet_subsys(&inet6_net_ops);
+	if (err)
+		goto register_pernet_fail;
+	err = ip6_mr_init();
+	if (err)
+		goto ipmr_fail;
+	err = icmpv6_init();
+	if (err)
+		goto icmp_fail;
+	err = ndisc_init();
+	if (err)
+		goto ndisc_fail;
+	err = igmp6_init();
+	if (err)
+		goto igmp_fail;
+
+	err = ipv6_netfilter_init();
+	if (err)
+		goto netfilter_fail;
+	/* Create /proc/foo6 entries. */
+#ifdef CONFIG_PROC_FS
+	err = -ENOMEM;
+	if (raw6_proc_init())
+		goto proc_raw6_fail;
+	if (udplite6_proc_init())
+		goto proc_udplite6_fail;
+	if (ipv6_misc_proc_init())
+		goto proc_misc6_fail;
+	if (if6_proc_init())
+		goto proc_if6_fail;
+#endif
+	err = ip6_route_init();
+	if (err)
+		goto ip6_route_fail;
+	err = ndisc_late_init();
+	if (err)
+		goto ndisc_late_fail;
+	err = ip6_flowlabel_init();
+	if (err)
+		goto ip6_flowlabel_fail;
+	err = ipv6_anycast_init();
+	if (err)
+		goto ipv6_anycast_fail;
+	err = addrconf_init();
+	if (err)
+		goto addrconf_fail;
+
+	/* Init v6 extension headers. */
+	err = ipv6_exthdrs_init();
+	if (err)
+		goto ipv6_exthdrs_fail;
+
+	err = ipv6_frag_init();
+	if (err)
+		goto ipv6_frag_fail;
+
+	/* Init v6 transport protocols. */
+	err = udpv6_init();
+	if (err)
+		goto udpv6_fail;
+
+	err = udplitev6_init();
+	if (err)
+		goto udplitev6_fail;
+
+	err = udpv6_offload_init();
+	if (err)
+		goto udpv6_offload_fail;
+
+	err = tcpv6_init();
+	if (err)
+		goto tcpv6_fail;
+
+	err = ipv6_packet_init();
+	if (err)
+		goto ipv6_packet_fail;
+
+	err = pingv6_init();
+	if (err)
+		goto pingv6_fail;
+
+	err = calipso_init();
+	if (err)
+		goto calipso_fail;
+
+	err = seg6_init();
+	if (err)
+		goto seg6_fail;
+
+	err = rpl_init();
+	if (err)
+		goto rpl_fail;
+
+	err = ioam6_init();
+	if (err)
+		goto ioam6_fail;
+
+	err = igmp6_late_init();
+	if (err)
+		goto igmp6_late_err;
+
+#ifdef CONFIG_SYSCTL
+	err = ipv6_sysctl_register();
+	if (err)
+		goto sysctl_fail;
+#endif
+
+	/* ensure that ipv6 stubs are visible only after ipv6 is ready */
+	wmb();
+	ipv6_stub = &ipv6_stub_impl;
+	ipv6_bpf_stub = &ipv6_bpf_stub_impl;
+out:
+	return err;
+
+#ifdef CONFIG_SYSCTL
+sysctl_fail:
+	igmp6_late_cleanup();
+#endif
+igmp6_late_err:
+	ioam6_exit();
+ioam6_fail:
+	rpl_exit();
+rpl_fail:
+	seg6_exit();
+seg6_fail:
+	calipso_exit();
+calipso_fail:
+	pingv6_exit();
+pingv6_fail:
+	ipv6_packet_cleanup();
+ipv6_packet_fail:
+	tcpv6_exit();
+tcpv6_fail:
+	udpv6_offload_exit();
+udpv6_offload_fail:
+	udplitev6_exit();
+udplitev6_fail:
+	udpv6_exit();
+udpv6_fail:
+	ipv6_frag_exit();
+ipv6_frag_fail:
+	ipv6_exthdrs_exit();
+ipv6_exthdrs_fail:
+	addrconf_cleanup();
+addrconf_fail:
+	ipv6_anycast_cleanup();
+ipv6_anycast_fail:
+	ip6_flowlabel_cleanup();
+ip6_flowlabel_fail:
+	ndisc_late_cleanup();
+ndisc_late_fail:
+	ip6_route_cleanup();
+ip6_route_fail:
+#ifdef CONFIG_PROC_FS
+	if6_proc_exit();
+proc_if6_fail:
+	ipv6_misc_proc_exit();
+proc_misc6_fail:
+	udplite6_proc_exit();
+proc_udplite6_fail:
+	raw6_proc_exit();
+proc_raw6_fail:
+#endif
+	ipv6_netfilter_fini();
+netfilter_fail:
+	igmp6_cleanup();
+igmp_fail:
+	ndisc_cleanup();
+ndisc_fail:
+	icmpv6_cleanup();
+icmp_fail:
+	ip6_mr_cleanup();
+ipmr_fail:
+	unregister_pernet_subsys(&inet6_net_ops);
+register_pernet_fail:
+	sock_unregister(PF_INET6);
+	rtnl_unregister_all(PF_INET6);
+out_sock_register_fail:
+	rawv6_exit();
+out_unregister_ping_proto:
+	proto_unregister(&pingv6_prot);
+out_unregister_raw_proto:
+	proto_unregister(&rawv6_prot);
+out_unregister_udplite_proto:
+	proto_unregister(&udplitev6_prot);
+out_unregister_udp_proto:
+	proto_unregister(&udpv6_prot);
+out_unregister_tcp_proto:
+	proto_unregister(&tcpv6_prot);
+	goto out;
+}
+module_init(inet6_init);
+
+MODULE_ALIAS_NETPROTO(PF_INET6);