Adding upstream version 6.1.76.upstream/6.1.76upstream

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

1 files changed, 1520 insertions, 0 deletions

diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
new file mode 100644
index 000000000..532f4478c
--- /dev/null
+++ b/net/ipv6/ipv6_sockglue.c
@@ -0,0 +1,1520 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *	IPv6 BSD socket options interface
+ *	Linux INET6 implementation
+ *
+ *	Authors:
+ *	Pedro Roque		<roque@di.fc.ul.pt>
+ *
+ *	Based on linux/net/ipv4/ip_sockglue.c
+ *
+ *	FIXME: Make the setsockopt code POSIX compliant: That is
+ *
+ *	o	Truncate getsockopt returns
+ *	o	Return an optlen of the truncated length if need be
+ *
+ *	Changes:
+ *	David L Stevens <dlstevens@us.ibm.com>:
+ *		- added multicast source filtering API for MLDv2
+ */
+
+#include <linux/module.h>
+#include <linux/capability.h>
+#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/mroute6.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/init.h>
+#include <linux/sysctl.h>
+#include <linux/netfilter.h>
+#include <linux/slab.h>
+
+#include <net/sock.h>
+#include <net/snmp.h>
+#include <net/ipv6.h>
+#include <net/ndisc.h>
+#include <net/protocol.h>
+#include <net/transp_v6.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
+#include <net/inet_common.h>
+#include <net/tcp.h>
+#include <net/udp.h>
+#include <net/udplite.h>
+#include <net/xfrm.h>
+#include <net/compat.h>
+#include <net/seg6.h>
+
+#include <linux/uaccess.h>
+
+struct ip6_ra_chain *ip6_ra_chain;
+DEFINE_RWLOCK(ip6_ra_lock);
+
+DEFINE_STATIC_KEY_FALSE(ip6_min_hopcount);
+
+int ip6_ra_control(struct sock *sk, int sel)
+{
+	struct ip6_ra_chain *ra, *new_ra, **rap;
+
+	/* RA packet may be delivered ONLY to IPPROTO_RAW socket */
+	if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num != IPPROTO_RAW)
+		return -ENOPROTOOPT;
+
+	new_ra = (sel >= 0) ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
+	if (sel >= 0 && !new_ra)
+		return -ENOMEM;
+
+	write_lock_bh(&ip6_ra_lock);
+	for (rap = &ip6_ra_chain; (ra = *rap) != NULL; rap = &ra->next) {
+		if (ra->sk == sk) {
+			if (sel >= 0) {
+				write_unlock_bh(&ip6_ra_lock);
+				kfree(new_ra);
+				return -EADDRINUSE;
+			}
+
+			*rap = ra->next;
+			write_unlock_bh(&ip6_ra_lock);
+
+			sock_put(sk);
+			kfree(ra);
+			return 0;
+		}
+	}
+	if (!new_ra) {
+		write_unlock_bh(&ip6_ra_lock);
+		return -ENOBUFS;
+	}
+	new_ra->sk = sk;
+	new_ra->sel = sel;
+	new_ra->next = ra;
+	*rap = new_ra;
+	sock_hold(sk);
+	write_unlock_bh(&ip6_ra_lock);
+	return 0;
+}
+
+struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
+					   struct ipv6_txoptions *opt)
+{
+	if (inet_sk(sk)->is_icsk) {
+		if (opt &&
+		    !((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) &&
+		    inet_sk(sk)->inet_daddr != LOOPBACK4_IPV6) {
+			struct inet_connection_sock *icsk = inet_csk(sk);
+			icsk->icsk_ext_hdr_len = opt->opt_flen + opt->opt_nflen;
+			icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
+		}
+	}
+	opt = xchg((__force struct ipv6_txoptions **)&inet6_sk(sk)->opt,
+		   opt);
+	sk_dst_reset(sk);
+
+	return opt;
+}
+
+static bool setsockopt_needs_rtnl(int optname)
+{
+	switch (optname) {
+	case IPV6_ADDRFORM:
+	case IPV6_ADD_MEMBERSHIP:
+	case IPV6_DROP_MEMBERSHIP:
+	case IPV6_JOIN_ANYCAST:
+	case IPV6_LEAVE_ANYCAST:
+	case MCAST_JOIN_GROUP:
+	case MCAST_LEAVE_GROUP:
+	case MCAST_JOIN_SOURCE_GROUP:
+	case MCAST_LEAVE_SOURCE_GROUP:
+	case MCAST_BLOCK_SOURCE:
+	case MCAST_UNBLOCK_SOURCE:
+	case MCAST_MSFILTER:
+		return true;
+	}
+	return false;
+}
+
+static int copy_group_source_from_sockptr(struct group_source_req *greqs,
+		sockptr_t optval, int optlen)
+{
+	if (in_compat_syscall()) {
+		struct compat_group_source_req gr32;
+
+		if (optlen < sizeof(gr32))
+			return -EINVAL;
+		if (copy_from_sockptr(&gr32, optval, sizeof(gr32)))
+			return -EFAULT;
+		greqs->gsr_interface = gr32.gsr_interface;
+		greqs->gsr_group = gr32.gsr_group;
+		greqs->gsr_source = gr32.gsr_source;
+	} else {
+		if (optlen < sizeof(*greqs))
+			return -EINVAL;
+		if (copy_from_sockptr(greqs, optval, sizeof(*greqs)))
+			return -EFAULT;
+	}
+
+	return 0;
+}
+
+static int do_ipv6_mcast_group_source(struct sock *sk, int optname,
+		sockptr_t optval, int optlen)
+{
+	struct group_source_req greqs;
+	int omode, add;
+	int ret;
+
+	ret = copy_group_source_from_sockptr(&greqs, optval, optlen);
+	if (ret)
+		return ret;
+
+	if (greqs.gsr_group.ss_family != AF_INET6 ||
+	    greqs.gsr_source.ss_family != AF_INET6)
+		return -EADDRNOTAVAIL;
+
+	if (optname == MCAST_BLOCK_SOURCE) {
+		omode = MCAST_EXCLUDE;
+		add = 1;
+	} else if (optname == MCAST_UNBLOCK_SOURCE) {
+		omode = MCAST_EXCLUDE;
+		add = 0;
+	} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
+		struct sockaddr_in6 *psin6;
+		int retv;
+
+		psin6 = (struct sockaddr_in6 *)&greqs.gsr_group;
+		retv = ipv6_sock_mc_join_ssm(sk, greqs.gsr_interface,
+					     &psin6->sin6_addr,
+					     MCAST_INCLUDE);
+		/* prior join w/ different source is ok */
+		if (retv && retv != -EADDRINUSE)
+			return retv;
+		omode = MCAST_INCLUDE;
+		add = 1;
+	} else /* MCAST_LEAVE_SOURCE_GROUP */ {
+		omode = MCAST_INCLUDE;
+		add = 0;
+	}
+	return ip6_mc_source(add, omode, sk, &greqs);
+}
+
+static int ipv6_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
+		int optlen)
+{
+	struct group_filter *gsf;
+	int ret;
+
+	if (optlen < GROUP_FILTER_SIZE(0))
+		return -EINVAL;
+	if (optlen > READ_ONCE(sysctl_optmem_max))
+		return -ENOBUFS;
+
+	gsf = memdup_sockptr(optval, optlen);
+	if (IS_ERR(gsf))
+		return PTR_ERR(gsf);
+
+	/* numsrc >= (4G-140)/128 overflow in 32 bits */
+	ret = -ENOBUFS;
+	if (gsf->gf_numsrc >= 0x1ffffffU ||
+	    gsf->gf_numsrc > sysctl_mld_max_msf)
+		goto out_free_gsf;
+
+	ret = -EINVAL;
+	if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen)
+		goto out_free_gsf;
+
+	ret = ip6_mc_msfilter(sk, gsf, gsf->gf_slist_flex);
+out_free_gsf:
+	kfree(gsf);
+	return ret;
+}
+
+static int compat_ipv6_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
+		int optlen)
+{
+	const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
+	struct compat_group_filter *gf32;
+	void *p;
+	int ret;
+	int n;
+
+	if (optlen < size0)
+		return -EINVAL;
+	if (optlen > READ_ONCE(sysctl_optmem_max) - 4)
+		return -ENOBUFS;
+
+	p = kmalloc(optlen + 4, GFP_KERNEL);
+	if (!p)
+		return -ENOMEM;
+
+	gf32 = p + 4; /* we want ->gf_group and ->gf_slist_flex aligned */
+	ret = -EFAULT;
+	if (copy_from_sockptr(gf32, optval, optlen))
+		goto out_free_p;
+
+	/* numsrc >= (4G-140)/128 overflow in 32 bits */
+	ret = -ENOBUFS;
+	n = gf32->gf_numsrc;
+	if (n >= 0x1ffffffU || n > sysctl_mld_max_msf)
+		goto out_free_p;
+
+	ret = -EINVAL;
+	if (offsetof(struct compat_group_filter, gf_slist_flex[n]) > optlen)
+		goto out_free_p;
+
+	ret = ip6_mc_msfilter(sk, &(struct group_filter){
+			.gf_interface = gf32->gf_interface,
+			.gf_group = gf32->gf_group,
+			.gf_fmode = gf32->gf_fmode,
+			.gf_numsrc = gf32->gf_numsrc}, gf32->gf_slist_flex);
+
+out_free_p:
+	kfree(p);
+	return ret;
+}
+
+static int ipv6_mcast_join_leave(struct sock *sk, int optname,
+		sockptr_t optval, int optlen)
+{
+	struct sockaddr_in6 *psin6;
+	struct group_req greq;
+
+	if (optlen < sizeof(greq))
+		return -EINVAL;
+	if (copy_from_sockptr(&greq, optval, sizeof(greq)))
+		return -EFAULT;
+
+	if (greq.gr_group.ss_family != AF_INET6)
+		return -EADDRNOTAVAIL;
+	psin6 = (struct sockaddr_in6 *)&greq.gr_group;
+	if (optname == MCAST_JOIN_GROUP)
+		return ipv6_sock_mc_join(sk, greq.gr_interface,
+					 &psin6->sin6_addr);
+	return ipv6_sock_mc_drop(sk, greq.gr_interface, &psin6->sin6_addr);
+}
+
+static int compat_ipv6_mcast_join_leave(struct sock *sk, int optname,
+		sockptr_t optval, int optlen)
+{
+	struct compat_group_req gr32;
+	struct sockaddr_in6 *psin6;
+
+	if (optlen < sizeof(gr32))
+		return -EINVAL;
+	if (copy_from_sockptr(&gr32, optval, sizeof(gr32)))
+		return -EFAULT;
+
+	if (gr32.gr_group.ss_family != AF_INET6)
+		return -EADDRNOTAVAIL;
+	psin6 = (struct sockaddr_in6 *)&gr32.gr_group;
+	if (optname == MCAST_JOIN_GROUP)
+		return ipv6_sock_mc_join(sk, gr32.gr_interface,
+					&psin6->sin6_addr);
+	return ipv6_sock_mc_drop(sk, gr32.gr_interface, &psin6->sin6_addr);
+}
+
+static int ipv6_set_opt_hdr(struct sock *sk, int optname, sockptr_t optval,
+		int optlen)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct ipv6_opt_hdr *new = NULL;
+	struct net *net = sock_net(sk);
+	struct ipv6_txoptions *opt;
+	int err;
+
+	/* hop-by-hop / destination options are privileged option */
+	if (optname != IPV6_RTHDR && !sockopt_ns_capable(net->user_ns, CAP_NET_RAW))
+		return -EPERM;
+
+	/* remove any sticky options header with a zero option
+	 * length, per RFC3542.
+	 */
+	if (optlen > 0) {
+		if (sockptr_is_null(optval))
+			return -EINVAL;
+		if (optlen < sizeof(struct ipv6_opt_hdr) ||
+		    optlen & 0x7 ||
+		    optlen > 8 * 255)
+			return -EINVAL;
+
+		new = memdup_sockptr(optval, optlen);
+		if (IS_ERR(new))
+			return PTR_ERR(new);
+		if (unlikely(ipv6_optlen(new) > optlen)) {
+			kfree(new);
+			return -EINVAL;
+		}
+	}
+
+	opt = rcu_dereference_protected(np->opt, lockdep_sock_is_held(sk));
+	opt = ipv6_renew_options(sk, opt, optname, new);
+	kfree(new);
+	if (IS_ERR(opt))
+		return PTR_ERR(opt);
+
+	/* routing header option needs extra check */
+	err = -EINVAL;
+	if (optname == IPV6_RTHDR && opt && opt->srcrt) {
+		struct ipv6_rt_hdr *rthdr = opt->srcrt;
+		switch (rthdr->type) {
+#if IS_ENABLED(CONFIG_IPV6_MIP6)
+		case IPV6_SRCRT_TYPE_2:
+			if (rthdr->hdrlen != 2 || rthdr->segments_left != 1)
+				goto sticky_done;
+			break;
+#endif
+		case IPV6_SRCRT_TYPE_4:
+		{
+			struct ipv6_sr_hdr *srh =
+				(struct ipv6_sr_hdr *)opt->srcrt;
+
+			if (!seg6_validate_srh(srh, optlen, false))
+				goto sticky_done;
+			break;
+		}
+		default:
+			goto sticky_done;
+		}
+	}
+
+	err = 0;
+	opt = ipv6_update_options(sk, opt);
+sticky_done:
+	if (opt) {
+		atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
+		txopt_put(opt);
+	}
+	return err;
+}
+
+int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
+		       sockptr_t optval, unsigned int optlen)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct net *net = sock_net(sk);
+	int val, valbool;
+	int retv = -ENOPROTOOPT;
+	bool needs_rtnl = setsockopt_needs_rtnl(optname);
+
+	if (sockptr_is_null(optval))
+		val = 0;
+	else {
+		if (optlen >= sizeof(int)) {
+			if (copy_from_sockptr(&val, optval, sizeof(val)))
+				return -EFAULT;
+		} else
+			val = 0;
+	}
+
+	valbool = (val != 0);
+
+	if (ip6_mroute_opt(optname))
+		return ip6_mroute_setsockopt(sk, optname, optval, optlen);
+
+	if (needs_rtnl)
+		rtnl_lock();
+	sockopt_lock_sock(sk);
+
+	/* Another thread has converted the socket into IPv4 with
+	 * IPV6_ADDRFORM concurrently.
+	 */
+	if (unlikely(sk->sk_family != AF_INET6))
+		goto unlock;
+
+	switch (optname) {
+
+	case IPV6_ADDRFORM:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		if (val == PF_INET) {
+			if (sk->sk_type == SOCK_RAW)
+				break;
+
+			if (sk->sk_protocol == IPPROTO_UDP ||
+			    sk->sk_protocol == IPPROTO_UDPLITE) {
+				struct udp_sock *up = udp_sk(sk);
+				if (up->pending == AF_INET6) {
+					retv = -EBUSY;
+					break;
+				}
+			} else if (sk->sk_protocol == IPPROTO_TCP) {
+				if (sk->sk_prot != &tcpv6_prot) {
+					retv = -EBUSY;
+					break;
+				}
+			} else {
+				break;
+			}
+
+			if (sk->sk_state != TCP_ESTABLISHED) {
+				retv = -ENOTCONN;
+				break;
+			}
+
+			if (ipv6_only_sock(sk) ||
+			    !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) {
+				retv = -EADDRNOTAVAIL;
+				break;
+			}
+
+			__ipv6_sock_mc_close(sk);
+			__ipv6_sock_ac_close(sk);
+
+			/*
+			 * Sock is moving from IPv6 to IPv4 (sk_prot), so
+			 * remove it from the refcnt debug socks count in the
+			 * original family...
+			 */
+			sk_refcnt_debug_dec(sk);
+
+			if (sk->sk_protocol == IPPROTO_TCP) {
+				struct inet_connection_sock *icsk = inet_csk(sk);
+
+				sock_prot_inuse_add(net, sk->sk_prot, -1);
+				sock_prot_inuse_add(net, &tcp_prot, 1);
+
+				/* Paired with READ_ONCE(sk->sk_prot) in inet6_stream_ops */
+				WRITE_ONCE(sk->sk_prot, &tcp_prot);
+				/* Paired with READ_ONCE() in tcp_(get|set)sockopt() */
+				WRITE_ONCE(icsk->icsk_af_ops, &ipv4_specific);
+				sk->sk_socket->ops = &inet_stream_ops;
+				sk->sk_family = PF_INET;
+				tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
+			} else {
+				struct proto *prot = &udp_prot;
+
+				if (sk->sk_protocol == IPPROTO_UDPLITE)
+					prot = &udplite_prot;
+
+				sock_prot_inuse_add(net, sk->sk_prot, -1);
+				sock_prot_inuse_add(net, prot, 1);
+
+				/* Paired with READ_ONCE(sk->sk_prot) in inet6_dgram_ops */
+				WRITE_ONCE(sk->sk_prot, prot);
+				sk->sk_socket->ops = &inet_dgram_ops;
+				sk->sk_family = PF_INET;
+			}
+
+			/* Disable all options not to allocate memory anymore,
+			 * but there is still a race.  See the lockless path
+			 * in udpv6_sendmsg() and ipv6_local_rxpmtu().
+			 */
+			np->rxopt.all = 0;
+
+			inet6_cleanup_sock(sk);
+
+			/*
+			 * ... and add it to the refcnt debug socks count
+			 * in the new family. -acme
+			 */
+			sk_refcnt_debug_inc(sk);
+			module_put(THIS_MODULE);
+			retv = 0;
+			break;
+		}
+		goto e_inval;
+
+	case IPV6_V6ONLY:
+		if (optlen < sizeof(int) ||
+		    inet_sk(sk)->inet_num)
+			goto e_inval;
+		sk->sk_ipv6only = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_RECVPKTINFO:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->rxopt.bits.rxinfo = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_2292PKTINFO:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->rxopt.bits.rxoinfo = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_RECVHOPLIMIT:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->rxopt.bits.rxhlim = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_2292HOPLIMIT:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->rxopt.bits.rxohlim = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_RECVRTHDR:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->rxopt.bits.srcrt = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_2292RTHDR:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->rxopt.bits.osrcrt = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_RECVHOPOPTS:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->rxopt.bits.hopopts = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_2292HOPOPTS:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->rxopt.bits.ohopopts = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_RECVDSTOPTS:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->rxopt.bits.dstopts = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_2292DSTOPTS:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->rxopt.bits.odstopts = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_TCLASS:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		if (val < -1 || val > 0xff)
+			goto e_inval;
+		/* RFC 3542, 6.5: default traffic class of 0x0 */
+		if (val == -1)
+			val = 0;
+		if (sk->sk_type == SOCK_STREAM) {
+			val &= ~INET_ECN_MASK;
+			val |= np->tclass & INET_ECN_MASK;
+		}
+		if (np->tclass != val) {
+			np->tclass = val;
+			sk_dst_reset(sk);
+		}
+		retv = 0;
+		break;
+
+	case IPV6_RECVTCLASS:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->rxopt.bits.rxtclass = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_FLOWINFO:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->rxopt.bits.rxflow = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_RECVPATHMTU:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->rxopt.bits.rxpmtu = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_TRANSPARENT:
+		if (valbool && !sockopt_ns_capable(net->user_ns, CAP_NET_RAW) &&
+		    !sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN)) {
+			retv = -EPERM;
+			break;
+		}
+		if (optlen < sizeof(int))
+			goto e_inval;
+		/* we don't have a separate transparent bit for IPV6 we use the one in the IPv4 socket */
+		inet_sk(sk)->transparent = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_FREEBIND:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		/* we also don't have a separate freebind bit for IPV6 */
+		inet_sk(sk)->freebind = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_RECVORIGDSTADDR:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->rxopt.bits.rxorigdstaddr = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_HOPOPTS:
+	case IPV6_RTHDRDSTOPTS:
+	case IPV6_RTHDR:
+	case IPV6_DSTOPTS:
+		retv = ipv6_set_opt_hdr(sk, optname, optval, optlen);
+		break;
+
+	case IPV6_PKTINFO:
+	{
+		struct in6_pktinfo pkt;
+
+		if (optlen == 0)
+			goto e_inval;
+		else if (optlen < sizeof(struct in6_pktinfo) ||
+			 sockptr_is_null(optval))
+			goto e_inval;
+
+		if (copy_from_sockptr(&pkt, optval, sizeof(pkt))) {
+			retv = -EFAULT;
+			break;
+		}
+		if (!sk_dev_equal_l3scope(sk, pkt.ipi6_ifindex))
+			goto e_inval;
+
+		np->sticky_pktinfo.ipi6_ifindex = pkt.ipi6_ifindex;
+		np->sticky_pktinfo.ipi6_addr = pkt.ipi6_addr;
+		retv = 0;
+		break;
+	}
+
+	case IPV6_2292PKTOPTIONS:
+	{
+		struct ipv6_txoptions *opt = NULL;
+		struct msghdr msg;
+		struct flowi6 fl6;
+		struct ipcm6_cookie ipc6;
+
+		memset(&fl6, 0, sizeof(fl6));
+		fl6.flowi6_oif = sk->sk_bound_dev_if;
+		fl6.flowi6_mark = sk->sk_mark;
+
+		if (optlen == 0)
+			goto update;
+
+		/* 1K is probably excessive
+		 * 1K is surely not enough, 2K per standard header is 16K.
+		 */
+		retv = -EINVAL;
+		if (optlen > 64*1024)
+			break;
+
+		opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL);
+		retv = -ENOBUFS;
+		if (!opt)
+			break;
+
+		memset(opt, 0, sizeof(*opt));
+		refcount_set(&opt->refcnt, 1);
+		opt->tot_len = sizeof(*opt) + optlen;
+		retv = -EFAULT;
+		if (copy_from_sockptr(opt + 1, optval, optlen))
+			goto done;
+
+		msg.msg_controllen = optlen;
+		msg.msg_control = (void *)(opt+1);
+		ipc6.opt = opt;
+
+		retv = ip6_datagram_send_ctl(net, sk, &msg, &fl6, &ipc6);
+		if (retv)
+			goto done;
+update:
+		retv = 0;
+		opt = ipv6_update_options(sk, opt);
+done:
+		if (opt) {
+			atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
+			txopt_put(opt);
+		}
+		break;
+	}
+	case IPV6_UNICAST_HOPS:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		if (val > 255 || val < -1)
+			goto e_inval;
+		np->hop_limit = val;
+		retv = 0;
+		break;
+
+	case IPV6_MULTICAST_HOPS:
+		if (sk->sk_type == SOCK_STREAM)
+			break;
+		if (optlen < sizeof(int))
+			goto e_inval;
+		if (val > 255 || val < -1)
+			goto e_inval;
+		np->mcast_hops = (val == -1 ? IPV6_DEFAULT_MCASTHOPS : val);
+		retv = 0;
+		break;
+
+	case IPV6_MULTICAST_LOOP:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		if (val != valbool)
+			goto e_inval;
+		np->mc_loop = valbool;
+		retv = 0;
+		break;
+
+	case IPV6_UNICAST_IF:
+	{
+		struct net_device *dev = NULL;
+		int ifindex;
+
+		if (optlen != sizeof(int))
+			goto e_inval;
+
+		ifindex = (__force int)ntohl((__force __be32)val);
+		if (ifindex == 0) {
+			np->ucast_oif = 0;
+			retv = 0;
+			break;
+		}
+
+		dev = dev_get_by_index(net, ifindex);
+		retv = -EADDRNOTAVAIL;
+		if (!dev)
+			break;
+		dev_put(dev);
+
+		retv = -EINVAL;
+		if (sk->sk_bound_dev_if)
+			break;
+
+		np->ucast_oif = ifindex;
+		retv = 0;
+		break;
+	}
+
+	case IPV6_MULTICAST_IF:
+		if (sk->sk_type == SOCK_STREAM)
+			break;
+		if (optlen < sizeof(int))
+			goto e_inval;
+
+		if (val) {
+			struct net_device *dev;
+			int midx;
+
+			rcu_read_lock();
+
+			dev = dev_get_by_index_rcu(net, val);
+			if (!dev) {
+				rcu_read_unlock();
+				retv = -ENODEV;
+				break;
+			}
+			midx = l3mdev_master_ifindex_rcu(dev);
+
+			rcu_read_unlock();
+
+			if (sk->sk_bound_dev_if &&
+			    sk->sk_bound_dev_if != val &&
+			    (!midx || midx != sk->sk_bound_dev_if))
+				goto e_inval;
+		}
+		np->mcast_oif = val;
+		retv = 0;
+		break;
+	case IPV6_ADD_MEMBERSHIP:
+	case IPV6_DROP_MEMBERSHIP:
+	{
+		struct ipv6_mreq mreq;
+
+		if (optlen < sizeof(struct ipv6_mreq))
+			goto e_inval;
+
+		retv = -EPROTO;
+		if (inet_sk(sk)->is_icsk)
+			break;
+
+		retv = -EFAULT;
+		if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
+			break;
+
+		if (optname == IPV6_ADD_MEMBERSHIP)
+			retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
+		else
+			retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
+		break;
+	}
+	case IPV6_JOIN_ANYCAST:
+	case IPV6_LEAVE_ANYCAST:
+	{
+		struct ipv6_mreq mreq;
+
+		if (optlen < sizeof(struct ipv6_mreq))
+			goto e_inval;
+
+		retv = -EFAULT;
+		if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
+			break;
+
+		if (optname == IPV6_JOIN_ANYCAST)
+			retv = ipv6_sock_ac_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
+		else
+			retv = ipv6_sock_ac_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
+		break;
+	}
+	case IPV6_MULTICAST_ALL:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->mc_all = valbool;
+		retv = 0;
+		break;
+
+	case MCAST_JOIN_GROUP:
+	case MCAST_LEAVE_GROUP:
+		if (in_compat_syscall())
+			retv = compat_ipv6_mcast_join_leave(sk, optname, optval,
+							    optlen);
+		else
+			retv = ipv6_mcast_join_leave(sk, optname, optval,
+						     optlen);
+		break;
+	case MCAST_JOIN_SOURCE_GROUP:
+	case MCAST_LEAVE_SOURCE_GROUP:
+	case MCAST_BLOCK_SOURCE:
+	case MCAST_UNBLOCK_SOURCE:
+		retv = do_ipv6_mcast_group_source(sk, optname, optval, optlen);
+		break;
+	case MCAST_MSFILTER:
+		if (in_compat_syscall())
+			retv = compat_ipv6_set_mcast_msfilter(sk, optval,
+							      optlen);
+		else
+			retv = ipv6_set_mcast_msfilter(sk, optval, optlen);
+		break;
+	case IPV6_ROUTER_ALERT:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		retv = ip6_ra_control(sk, val);
+		break;
+	case IPV6_ROUTER_ALERT_ISOLATE:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->rtalert_isolate = valbool;
+		retv = 0;
+		break;
+	case IPV6_MTU_DISCOVER:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		if (val < IPV6_PMTUDISC_DONT || val > IPV6_PMTUDISC_OMIT)
+			goto e_inval;
+		np->pmtudisc = val;
+		retv = 0;
+		break;
+	case IPV6_MTU:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		if (val && val < IPV6_MIN_MTU)
+			goto e_inval;
+		np->frag_size = val;
+		retv = 0;
+		break;
+	case IPV6_RECVERR:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->recverr = valbool;
+		if (!val)
+			skb_queue_purge(&sk->sk_error_queue);
+		retv = 0;
+		break;
+	case IPV6_FLOWINFO_SEND:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		np->sndflow = valbool;
+		retv = 0;
+		break;
+	case IPV6_FLOWLABEL_MGR:
+		retv = ipv6_flowlabel_opt(sk, optval, optlen);
+		break;
+	case IPV6_IPSEC_POLICY:
+	case IPV6_XFRM_POLICY:
+		retv = -EPERM;
+		if (!sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN))
+			break;
+		retv = xfrm_user_policy(sk, optname, optval, optlen);
+		break;
+
+	case IPV6_ADDR_PREFERENCES:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		retv = __ip6_sock_set_addr_preferences(sk, val);
+		break;
+	case IPV6_MINHOPCOUNT:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		if (val < 0 || val > 255)
+			goto e_inval;
+
+		if (val)
+			static_branch_enable(&ip6_min_hopcount);
+
+		/* tcp_v6_err() and tcp_v6_rcv() might read min_hopcount
+		 * while we are changing it.
+		 */
+		WRITE_ONCE(np->min_hopcount, val);
+		retv = 0;
+		break;
+	case IPV6_DONTFRAG:
+		np->dontfrag = valbool;
+		retv = 0;
+		break;
+	case IPV6_AUTOFLOWLABEL:
+		np->autoflowlabel = valbool;
+		np->autoflowlabel_set = 1;
+		retv = 0;
+		break;
+	case IPV6_RECVFRAGSIZE:
+		np->rxopt.bits.recvfragsize = valbool;
+		retv = 0;
+		break;
+	case IPV6_RECVERR_RFC4884:
+		if (optlen < sizeof(int))
+			goto e_inval;
+		if (val < 0 || val > 1)
+			goto e_inval;
+		np->recverr_rfc4884 = valbool;
+		retv = 0;
+		break;
+	}
+
+unlock:
+	sockopt_release_sock(sk);
+	if (needs_rtnl)
+		rtnl_unlock();
+
+	return retv;
+
+e_inval:
+	sockopt_release_sock(sk);
+	if (needs_rtnl)
+		rtnl_unlock();
+	return -EINVAL;
+}
+
+int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
+		    unsigned int optlen)
+{
+	int err;
+
+	if (level == SOL_IP && sk->sk_type != SOCK_RAW)
+		return udp_prot.setsockopt(sk, level, optname, optval, optlen);
+
+	if (level != SOL_IPV6)
+		return -ENOPROTOOPT;
+
+	err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);
+#ifdef CONFIG_NETFILTER
+	/* we need to exclude all possible ENOPROTOOPTs except default case */
+	if (err == -ENOPROTOOPT && optname != IPV6_IPSEC_POLICY &&
+			optname != IPV6_XFRM_POLICY)
+		err = nf_setsockopt(sk, PF_INET6, optname, optval, optlen);
+#endif
+	return err;
+}
+EXPORT_SYMBOL(ipv6_setsockopt);
+
+static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
+				  int optname, sockptr_t optval, int len)
+{
+	struct ipv6_opt_hdr *hdr;
+
+	if (!opt)
+		return 0;
+
+	switch (optname) {
+	case IPV6_HOPOPTS:
+		hdr = opt->hopopt;
+		break;
+	case IPV6_RTHDRDSTOPTS:
+		hdr = opt->dst0opt;
+		break;
+	case IPV6_RTHDR:
+		hdr = (struct ipv6_opt_hdr *)opt->srcrt;
+		break;
+	case IPV6_DSTOPTS:
+		hdr = opt->dst1opt;
+		break;
+	default:
+		return -EINVAL;	/* should not happen */
+	}
+
+	if (!hdr)
+		return 0;
+
+	len = min_t(unsigned int, len, ipv6_optlen(hdr));
+	if (copy_to_sockptr(optval, hdr, len))
+		return -EFAULT;
+	return len;
+}
+
+static int ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
+			     sockptr_t optlen, int len)
+{
+	const int size0 = offsetof(struct group_filter, gf_slist_flex);
+	struct group_filter gsf;
+	int num;
+	int err;
+
+	if (len < size0)
+		return -EINVAL;
+	if (copy_from_sockptr(&gsf, optval, size0))
+		return -EFAULT;
+	if (gsf.gf_group.ss_family != AF_INET6)
+		return -EADDRNOTAVAIL;
+	num = gsf.gf_numsrc;
+	sockopt_lock_sock(sk);
+	err = ip6_mc_msfget(sk, &gsf, optval, size0);
+	if (!err) {
+		if (num > gsf.gf_numsrc)
+			num = gsf.gf_numsrc;
+		len = GROUP_FILTER_SIZE(num);
+		if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
+		    copy_to_sockptr(optval, &gsf, size0))
+			err = -EFAULT;
+	}
+	sockopt_release_sock(sk);
+	return err;
+}
+
+static int compat_ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
+				    sockptr_t optlen, int len)
+{
+	const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
+	struct compat_group_filter gf32;
+	struct group_filter gf;
+	int err;
+	int num;
+
+	if (len < size0)
+		return -EINVAL;
+
+	if (copy_from_sockptr(&gf32, optval, size0))
+		return -EFAULT;
+	gf.gf_interface = gf32.gf_interface;
+	gf.gf_fmode = gf32.gf_fmode;
+	num = gf.gf_numsrc = gf32.gf_numsrc;
+	gf.gf_group = gf32.gf_group;
+
+	if (gf.gf_group.ss_family != AF_INET6)
+		return -EADDRNOTAVAIL;
+
+	sockopt_lock_sock(sk);
+	err = ip6_mc_msfget(sk, &gf, optval, size0);
+	sockopt_release_sock(sk);
+	if (err)
+		return err;
+	if (num > gf.gf_numsrc)
+		num = gf.gf_numsrc;
+	len = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32));
+	if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
+	    copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_fmode),
+				   &gf.gf_fmode, sizeof(gf32.gf_fmode)) ||
+	    copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_numsrc),
+				   &gf.gf_numsrc, sizeof(gf32.gf_numsrc)))
+		return -EFAULT;
+	return 0;
+}
+
+int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
+		       sockptr_t optval, sockptr_t optlen)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	int len;
+	int val;
+
+	if (ip6_mroute_opt(optname))
+		return ip6_mroute_getsockopt(sk, optname, optval, optlen);
+
+	if (copy_from_sockptr(&len, optlen, sizeof(int)))
+		return -EFAULT;
+	switch (optname) {
+	case IPV6_ADDRFORM:
+		if (sk->sk_protocol != IPPROTO_UDP &&
+		    sk->sk_protocol != IPPROTO_UDPLITE &&
+		    sk->sk_protocol != IPPROTO_TCP)
+			return -ENOPROTOOPT;
+		if (sk->sk_state != TCP_ESTABLISHED)
+			return -ENOTCONN;
+		val = sk->sk_family;
+		break;
+	case MCAST_MSFILTER:
+		if (in_compat_syscall())
+			return compat_ipv6_get_msfilter(sk, optval, optlen, len);
+		return ipv6_get_msfilter(sk, optval, optlen, len);
+	case IPV6_2292PKTOPTIONS:
+	{
+		struct msghdr msg;
+		struct sk_buff *skb;
+
+		if (sk->sk_type != SOCK_STREAM)
+			return -ENOPROTOOPT;
+
+		if (optval.is_kernel) {
+			msg.msg_control_is_user = false;
+			msg.msg_control = optval.kernel;
+		} else {
+			msg.msg_control_is_user = true;
+			msg.msg_control_user = optval.user;
+		}
+		msg.msg_controllen = len;
+		msg.msg_flags = 0;
+
+		sockopt_lock_sock(sk);
+		skb = np->pktoptions;
+		if (skb)
+			ip6_datagram_recv_ctl(sk, &msg, skb);
+		sockopt_release_sock(sk);
+		if (!skb) {
+			if (np->rxopt.bits.rxinfo) {
+				struct in6_pktinfo src_info;
+				src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
+					np->sticky_pktinfo.ipi6_ifindex;
+				src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr : np->sticky_pktinfo.ipi6_addr;
+				put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
+			}
+			if (np->rxopt.bits.rxhlim) {
+				int hlim = np->mcast_hops;
+				put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
+			}
+			if (np->rxopt.bits.rxtclass) {
+				int tclass = (int)ip6_tclass(np->rcv_flowinfo);
+
+				put_cmsg(&msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
+			}
+			if (np->rxopt.bits.rxoinfo) {
+				struct in6_pktinfo src_info;
+				src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
+					np->sticky_pktinfo.ipi6_ifindex;
+				src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr :
+								     np->sticky_pktinfo.ipi6_addr;
+				put_cmsg(&msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
+			}
+			if (np->rxopt.bits.rxohlim) {
+				int hlim = np->mcast_hops;
+				put_cmsg(&msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
+			}
+			if (np->rxopt.bits.rxflow) {
+				__be32 flowinfo = np->rcv_flowinfo;
+
+				put_cmsg(&msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
+			}
+		}
+		len -= msg.msg_controllen;
+		return copy_to_sockptr(optlen, &len, sizeof(int));
+	}
+	case IPV6_MTU:
+	{
+		struct dst_entry *dst;
+
+		val = 0;
+		rcu_read_lock();
+		dst = __sk_dst_get(sk);
+		if (dst)
+			val = dst_mtu(dst);
+		rcu_read_unlock();
+		if (!val)
+			return -ENOTCONN;
+		break;
+	}
+
+	case IPV6_V6ONLY:
+		val = sk->sk_ipv6only;
+		break;
+
+	case IPV6_RECVPKTINFO:
+		val = np->rxopt.bits.rxinfo;
+		break;
+
+	case IPV6_2292PKTINFO:
+		val = np->rxopt.bits.rxoinfo;
+		break;
+
+	case IPV6_RECVHOPLIMIT:
+		val = np->rxopt.bits.rxhlim;
+		break;
+
+	case IPV6_2292HOPLIMIT:
+		val = np->rxopt.bits.rxohlim;
+		break;
+
+	case IPV6_RECVRTHDR:
+		val = np->rxopt.bits.srcrt;
+		break;
+
+	case IPV6_2292RTHDR:
+		val = np->rxopt.bits.osrcrt;
+		break;
+
+	case IPV6_HOPOPTS:
+	case IPV6_RTHDRDSTOPTS:
+	case IPV6_RTHDR:
+	case IPV6_DSTOPTS:
+	{
+		struct ipv6_txoptions *opt;
+
+		sockopt_lock_sock(sk);
+		opt = rcu_dereference_protected(np->opt,
+						lockdep_sock_is_held(sk));
+		len = ipv6_getsockopt_sticky(sk, opt, optname, optval, len);
+		sockopt_release_sock(sk);
+		/* check if ipv6_getsockopt_sticky() returns err code */
+		if (len < 0)
+			return len;
+		return copy_to_sockptr(optlen, &len, sizeof(int));
+	}
+
+	case IPV6_RECVHOPOPTS:
+		val = np->rxopt.bits.hopopts;
+		break;
+
+	case IPV6_2292HOPOPTS:
+		val = np->rxopt.bits.ohopopts;
+		break;
+
+	case IPV6_RECVDSTOPTS:
+		val = np->rxopt.bits.dstopts;
+		break;
+
+	case IPV6_2292DSTOPTS:
+		val = np->rxopt.bits.odstopts;
+		break;
+
+	case IPV6_TCLASS:
+		val = np->tclass;
+		break;
+
+	case IPV6_RECVTCLASS:
+		val = np->rxopt.bits.rxtclass;
+		break;
+
+	case IPV6_FLOWINFO:
+		val = np->rxopt.bits.rxflow;
+		break;
+
+	case IPV6_RECVPATHMTU:
+		val = np->rxopt.bits.rxpmtu;
+		break;
+
+	case IPV6_PATHMTU:
+	{
+		struct dst_entry *dst;
+		struct ip6_mtuinfo mtuinfo;
+
+		if (len < sizeof(mtuinfo))
+			return -EINVAL;
+
+		len = sizeof(mtuinfo);
+		memset(&mtuinfo, 0, sizeof(mtuinfo));
+
+		rcu_read_lock();
+		dst = __sk_dst_get(sk);
+		if (dst)
+			mtuinfo.ip6m_mtu = dst_mtu(dst);
+		rcu_read_unlock();
+		if (!mtuinfo.ip6m_mtu)
+			return -ENOTCONN;
+
+		if (copy_to_sockptr(optlen, &len, sizeof(int)))
+			return -EFAULT;
+		if (copy_to_sockptr(optval, &mtuinfo, len))
+			return -EFAULT;
+
+		return 0;
+	}
+
+	case IPV6_TRANSPARENT:
+		val = inet_sk(sk)->transparent;
+		break;
+
+	case IPV6_FREEBIND:
+		val = inet_sk(sk)->freebind;
+		break;
+
+	case IPV6_RECVORIGDSTADDR:
+		val = np->rxopt.bits.rxorigdstaddr;
+		break;
+
+	case IPV6_UNICAST_HOPS:
+	case IPV6_MULTICAST_HOPS:
+	{
+		struct dst_entry *dst;
+
+		if (optname == IPV6_UNICAST_HOPS)
+			val = np->hop_limit;
+		else
+			val = np->mcast_hops;
+
+		if (val < 0) {
+			rcu_read_lock();
+			dst = __sk_dst_get(sk);
+			if (dst)
+				val = ip6_dst_hoplimit(dst);
+			rcu_read_unlock();
+		}
+
+		if (val < 0)
+			val = sock_net(sk)->ipv6.devconf_all->hop_limit;
+		break;
+	}
+
+	case IPV6_MULTICAST_LOOP:
+		val = np->mc_loop;
+		break;
+
+	case IPV6_MULTICAST_IF:
+		val = np->mcast_oif;
+		break;
+
+	case IPV6_MULTICAST_ALL:
+		val = np->mc_all;
+		break;
+
+	case IPV6_UNICAST_IF:
+		val = (__force int)htonl((__u32) np->ucast_oif);
+		break;
+
+	case IPV6_MTU_DISCOVER:
+		val = np->pmtudisc;
+		break;
+
+	case IPV6_RECVERR:
+		val = np->recverr;
+		break;
+
+	case IPV6_FLOWINFO_SEND:
+		val = np->sndflow;
+		break;
+
+	case IPV6_FLOWLABEL_MGR:
+	{
+		struct in6_flowlabel_req freq;
+		int flags;
+
+		if (len < sizeof(freq))
+			return -EINVAL;
+
+		if (copy_from_sockptr(&freq, optval, sizeof(freq)))
+			return -EFAULT;
+
+		if (freq.flr_action != IPV6_FL_A_GET)
+			return -EINVAL;
+
+		len = sizeof(freq);
+		flags = freq.flr_flags;
+
+		memset(&freq, 0, sizeof(freq));
+
+		val = ipv6_flowlabel_opt_get(sk, &freq, flags);
+		if (val < 0)
+			return val;
+
+		if (copy_to_sockptr(optlen, &len, sizeof(int)))
+			return -EFAULT;
+		if (copy_to_sockptr(optval, &freq, len))
+			return -EFAULT;
+
+		return 0;
+	}
+
+	case IPV6_ADDR_PREFERENCES:
+		val = 0;
+
+		if (np->srcprefs & IPV6_PREFER_SRC_TMP)
+			val |= IPV6_PREFER_SRC_TMP;
+		else if (np->srcprefs & IPV6_PREFER_SRC_PUBLIC)
+			val |= IPV6_PREFER_SRC_PUBLIC;
+		else {
+			/* XXX: should we return system default? */
+			val |= IPV6_PREFER_SRC_PUBTMP_DEFAULT;
+		}
+
+		if (np->srcprefs & IPV6_PREFER_SRC_COA)
+			val |= IPV6_PREFER_SRC_COA;
+		else
+			val |= IPV6_PREFER_SRC_HOME;
+		break;
+
+	case IPV6_MINHOPCOUNT:
+		val = np->min_hopcount;
+		break;
+
+	case IPV6_DONTFRAG:
+		val = np->dontfrag;
+		break;
+
+	case IPV6_AUTOFLOWLABEL:
+		val = ip6_autoflowlabel(sock_net(sk), np);
+		break;
+
+	case IPV6_RECVFRAGSIZE:
+		val = np->rxopt.bits.recvfragsize;
+		break;
+
+	case IPV6_ROUTER_ALERT_ISOLATE:
+		val = np->rtalert_isolate;
+		break;
+
+	case IPV6_RECVERR_RFC4884:
+		val = np->recverr_rfc4884;
+		break;
+
+	default:
+		return -ENOPROTOOPT;
+	}
+	len = min_t(unsigned int, sizeof(int), len);
+	if (copy_to_sockptr(optlen, &len, sizeof(int)))
+		return -EFAULT;
+	if (copy_to_sockptr(optval, &val, len))
+		return -EFAULT;
+	return 0;
+}
+
+int ipv6_getsockopt(struct sock *sk, int level, int optname,
+		    char __user *optval, int __user *optlen)
+{
+	int err;
+
+	if (level == SOL_IP && sk->sk_type != SOCK_RAW)
+		return udp_prot.getsockopt(sk, level, optname, optval, optlen);
+
+	if (level != SOL_IPV6)
+		return -ENOPROTOOPT;
+
+	err = do_ipv6_getsockopt(sk, level, optname,
+				 USER_SOCKPTR(optval), USER_SOCKPTR(optlen));
+#ifdef CONFIG_NETFILTER
+	/* we need to exclude all possible ENOPROTOOPTs except default case */
+	if (err == -ENOPROTOOPT && optname != IPV6_2292PKTOPTIONS) {
+		int len;
+
+		if (get_user(len, optlen))
+			return -EFAULT;
+
+		err = nf_getsockopt(sk, PF_INET6, optname, optval, &len);
+		if (err >= 0)
+			err = put_user(len, optlen);
+	}
+#endif
+	return err;
+}
+EXPORT_SYMBOL(ipv6_getsockopt);