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v6.9.4
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *	IPv6 BSD socket options interface
   4 *	Linux INET6 implementation
   5 *
   6 *	Authors:
   7 *	Pedro Roque		<roque@di.fc.ul.pt>
   8 *
   9 *	Based on linux/net/ipv4/ip_sockglue.c
  10 *
  11 *	FIXME: Make the setsockopt code POSIX compliant: That is
  12 *
  13 *	o	Truncate getsockopt returns
  14 *	o	Return an optlen of the truncated length if need be
  15 *
  16 *	Changes:
  17 *	David L Stevens <dlstevens@us.ibm.com>:
  18 *		- added multicast source filtering API for MLDv2
  19 */
  20
  21#include <linux/module.h>
  22#include <linux/capability.h>
  23#include <linux/errno.h>
  24#include <linux/types.h>
  25#include <linux/socket.h>
  26#include <linux/sockios.h>
  27#include <linux/net.h>
  28#include <linux/in6.h>
  29#include <linux/mroute6.h>
  30#include <linux/netdevice.h>
  31#include <linux/if_arp.h>
  32#include <linux/init.h>
  33#include <linux/sysctl.h>
  34#include <linux/netfilter.h>
  35#include <linux/slab.h>
  36
  37#include <net/sock.h>
  38#include <net/snmp.h>
  39#include <net/ipv6.h>
  40#include <net/ndisc.h>
  41#include <net/protocol.h>
  42#include <net/transp_v6.h>
  43#include <net/ip6_route.h>
  44#include <net/addrconf.h>
  45#include <net/inet_common.h>
  46#include <net/tcp.h>
  47#include <net/udp.h>
  48#include <net/udplite.h>
  49#include <net/xfrm.h>
  50#include <net/compat.h>
  51#include <net/seg6.h>
  52
  53#include <linux/uaccess.h>
  54
  55struct ip6_ra_chain *ip6_ra_chain;
  56DEFINE_RWLOCK(ip6_ra_lock);
  57
  58DEFINE_STATIC_KEY_FALSE(ip6_min_hopcount);
  59
  60int ip6_ra_control(struct sock *sk, int sel)
  61{
  62	struct ip6_ra_chain *ra, *new_ra, **rap;
  63
  64	/* RA packet may be delivered ONLY to IPPROTO_RAW socket */
  65	if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num != IPPROTO_RAW)
  66		return -ENOPROTOOPT;
  67
  68	new_ra = (sel >= 0) ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
  69	if (sel >= 0 && !new_ra)
  70		return -ENOMEM;
  71
  72	write_lock_bh(&ip6_ra_lock);
  73	for (rap = &ip6_ra_chain; (ra = *rap) != NULL; rap = &ra->next) {
  74		if (ra->sk == sk) {
  75			if (sel >= 0) {
  76				write_unlock_bh(&ip6_ra_lock);
  77				kfree(new_ra);
  78				return -EADDRINUSE;
  79			}
  80
  81			*rap = ra->next;
  82			write_unlock_bh(&ip6_ra_lock);
  83
  84			sock_put(sk);
  85			kfree(ra);
  86			return 0;
  87		}
  88	}
  89	if (!new_ra) {
  90		write_unlock_bh(&ip6_ra_lock);
  91		return -ENOBUFS;
  92	}
  93	new_ra->sk = sk;
  94	new_ra->sel = sel;
  95	new_ra->next = ra;
  96	*rap = new_ra;
  97	sock_hold(sk);
  98	write_unlock_bh(&ip6_ra_lock);
  99	return 0;
 100}
 101
 102struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
 103					   struct ipv6_txoptions *opt)
 104{
 105	if (inet_test_bit(IS_ICSK, sk)) {
 106		if (opt &&
 107		    !((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) &&
 108		    inet_sk(sk)->inet_daddr != LOOPBACK4_IPV6) {
 109			struct inet_connection_sock *icsk = inet_csk(sk);
 110			icsk->icsk_ext_hdr_len = opt->opt_flen + opt->opt_nflen;
 111			icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
 112		}
 113	}
 114	opt = xchg((__force struct ipv6_txoptions **)&inet6_sk(sk)->opt,
 115		   opt);
 116	sk_dst_reset(sk);
 117
 118	return opt;
 119}
 120
 121static bool setsockopt_needs_rtnl(int optname)
 122{
 123	switch (optname) {
 124	case IPV6_ADDRFORM:
 125	case IPV6_ADD_MEMBERSHIP:
 126	case IPV6_DROP_MEMBERSHIP:
 127	case IPV6_JOIN_ANYCAST:
 128	case IPV6_LEAVE_ANYCAST:
 129	case MCAST_JOIN_GROUP:
 130	case MCAST_LEAVE_GROUP:
 131	case MCAST_JOIN_SOURCE_GROUP:
 132	case MCAST_LEAVE_SOURCE_GROUP:
 133	case MCAST_BLOCK_SOURCE:
 134	case MCAST_UNBLOCK_SOURCE:
 135	case MCAST_MSFILTER:
 136		return true;
 137	}
 138	return false;
 139}
 140
 141static int copy_group_source_from_sockptr(struct group_source_req *greqs,
 142		sockptr_t optval, int optlen)
 143{
 144	if (in_compat_syscall()) {
 145		struct compat_group_source_req gr32;
 146
 147		if (optlen < sizeof(gr32))
 148			return -EINVAL;
 149		if (copy_from_sockptr(&gr32, optval, sizeof(gr32)))
 150			return -EFAULT;
 151		greqs->gsr_interface = gr32.gsr_interface;
 152		greqs->gsr_group = gr32.gsr_group;
 153		greqs->gsr_source = gr32.gsr_source;
 154	} else {
 155		if (optlen < sizeof(*greqs))
 156			return -EINVAL;
 157		if (copy_from_sockptr(greqs, optval, sizeof(*greqs)))
 158			return -EFAULT;
 159	}
 160
 161	return 0;
 162}
 163
 164static int do_ipv6_mcast_group_source(struct sock *sk, int optname,
 165		sockptr_t optval, int optlen)
 166{
 167	struct group_source_req greqs;
 168	int omode, add;
 169	int ret;
 170
 171	ret = copy_group_source_from_sockptr(&greqs, optval, optlen);
 172	if (ret)
 173		return ret;
 174
 175	if (greqs.gsr_group.ss_family != AF_INET6 ||
 176	    greqs.gsr_source.ss_family != AF_INET6)
 177		return -EADDRNOTAVAIL;
 178
 179	if (optname == MCAST_BLOCK_SOURCE) {
 180		omode = MCAST_EXCLUDE;
 181		add = 1;
 182	} else if (optname == MCAST_UNBLOCK_SOURCE) {
 183		omode = MCAST_EXCLUDE;
 184		add = 0;
 185	} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
 186		struct sockaddr_in6 *psin6;
 187		int retv;
 188
 189		psin6 = (struct sockaddr_in6 *)&greqs.gsr_group;
 190		retv = ipv6_sock_mc_join_ssm(sk, greqs.gsr_interface,
 191					     &psin6->sin6_addr,
 192					     MCAST_INCLUDE);
 193		/* prior join w/ different source is ok */
 194		if (retv && retv != -EADDRINUSE)
 195			return retv;
 196		omode = MCAST_INCLUDE;
 197		add = 1;
 198	} else /* MCAST_LEAVE_SOURCE_GROUP */ {
 199		omode = MCAST_INCLUDE;
 200		add = 0;
 201	}
 202	return ip6_mc_source(add, omode, sk, &greqs);
 203}
 204
 205static int ipv6_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
 206		int optlen)
 207{
 208	struct group_filter *gsf;
 209	int ret;
 210
 211	if (optlen < GROUP_FILTER_SIZE(0))
 212		return -EINVAL;
 213	if (optlen > READ_ONCE(sock_net(sk)->core.sysctl_optmem_max))
 214		return -ENOBUFS;
 215
 216	gsf = memdup_sockptr(optval, optlen);
 217	if (IS_ERR(gsf))
 218		return PTR_ERR(gsf);
 219
 220	/* numsrc >= (4G-140)/128 overflow in 32 bits */
 221	ret = -ENOBUFS;
 222	if (gsf->gf_numsrc >= 0x1ffffffU ||
 223	    gsf->gf_numsrc > sysctl_mld_max_msf)
 224		goto out_free_gsf;
 225
 226	ret = -EINVAL;
 227	if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen)
 228		goto out_free_gsf;
 229
 230	ret = ip6_mc_msfilter(sk, gsf, gsf->gf_slist_flex);
 231out_free_gsf:
 232	kfree(gsf);
 233	return ret;
 234}
 235
 236static int compat_ipv6_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
 237		int optlen)
 238{
 239	const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
 240	struct compat_group_filter *gf32;
 241	void *p;
 242	int ret;
 243	int n;
 244
 245	if (optlen < size0)
 246		return -EINVAL;
 247	if (optlen > READ_ONCE(sock_net(sk)->core.sysctl_optmem_max) - 4)
 248		return -ENOBUFS;
 249
 250	p = kmalloc(optlen + 4, GFP_KERNEL);
 251	if (!p)
 252		return -ENOMEM;
 253
 254	gf32 = p + 4; /* we want ->gf_group and ->gf_slist_flex aligned */
 255	ret = -EFAULT;
 256	if (copy_from_sockptr(gf32, optval, optlen))
 257		goto out_free_p;
 258
 259	/* numsrc >= (4G-140)/128 overflow in 32 bits */
 260	ret = -ENOBUFS;
 261	n = gf32->gf_numsrc;
 262	if (n >= 0x1ffffffU || n > sysctl_mld_max_msf)
 263		goto out_free_p;
 264
 265	ret = -EINVAL;
 266	if (offsetof(struct compat_group_filter, gf_slist_flex[n]) > optlen)
 267		goto out_free_p;
 268
 269	ret = ip6_mc_msfilter(sk, &(struct group_filter){
 270			.gf_interface = gf32->gf_interface,
 271			.gf_group = gf32->gf_group,
 272			.gf_fmode = gf32->gf_fmode,
 273			.gf_numsrc = gf32->gf_numsrc}, gf32->gf_slist_flex);
 274
 275out_free_p:
 276	kfree(p);
 277	return ret;
 278}
 279
 280static int ipv6_mcast_join_leave(struct sock *sk, int optname,
 281		sockptr_t optval, int optlen)
 282{
 283	struct sockaddr_in6 *psin6;
 284	struct group_req greq;
 285
 286	if (optlen < sizeof(greq))
 287		return -EINVAL;
 288	if (copy_from_sockptr(&greq, optval, sizeof(greq)))
 289		return -EFAULT;
 290
 291	if (greq.gr_group.ss_family != AF_INET6)
 292		return -EADDRNOTAVAIL;
 293	psin6 = (struct sockaddr_in6 *)&greq.gr_group;
 294	if (optname == MCAST_JOIN_GROUP)
 295		return ipv6_sock_mc_join(sk, greq.gr_interface,
 296					 &psin6->sin6_addr);
 297	return ipv6_sock_mc_drop(sk, greq.gr_interface, &psin6->sin6_addr);
 298}
 299
 300static int compat_ipv6_mcast_join_leave(struct sock *sk, int optname,
 301		sockptr_t optval, int optlen)
 302{
 303	struct compat_group_req gr32;
 304	struct sockaddr_in6 *psin6;
 305
 306	if (optlen < sizeof(gr32))
 307		return -EINVAL;
 308	if (copy_from_sockptr(&gr32, optval, sizeof(gr32)))
 309		return -EFAULT;
 310
 311	if (gr32.gr_group.ss_family != AF_INET6)
 312		return -EADDRNOTAVAIL;
 313	psin6 = (struct sockaddr_in6 *)&gr32.gr_group;
 314	if (optname == MCAST_JOIN_GROUP)
 315		return ipv6_sock_mc_join(sk, gr32.gr_interface,
 316					&psin6->sin6_addr);
 317	return ipv6_sock_mc_drop(sk, gr32.gr_interface, &psin6->sin6_addr);
 318}
 319
 320static int ipv6_set_opt_hdr(struct sock *sk, int optname, sockptr_t optval,
 321		int optlen)
 322{
 323	struct ipv6_pinfo *np = inet6_sk(sk);
 324	struct ipv6_opt_hdr *new = NULL;
 325	struct net *net = sock_net(sk);
 326	struct ipv6_txoptions *opt;
 327	int err;
 328
 329	/* hop-by-hop / destination options are privileged option */
 330	if (optname != IPV6_RTHDR && !sockopt_ns_capable(net->user_ns, CAP_NET_RAW))
 331		return -EPERM;
 332
 333	/* remove any sticky options header with a zero option
 334	 * length, per RFC3542.
 335	 */
 336	if (optlen > 0) {
 337		if (sockptr_is_null(optval))
 338			return -EINVAL;
 339		if (optlen < sizeof(struct ipv6_opt_hdr) ||
 340		    optlen & 0x7 ||
 341		    optlen > 8 * 255)
 342			return -EINVAL;
 343
 344		new = memdup_sockptr(optval, optlen);
 345		if (IS_ERR(new))
 346			return PTR_ERR(new);
 347		if (unlikely(ipv6_optlen(new) > optlen)) {
 348			kfree(new);
 349			return -EINVAL;
 350		}
 351	}
 352
 353	opt = rcu_dereference_protected(np->opt, lockdep_sock_is_held(sk));
 354	opt = ipv6_renew_options(sk, opt, optname, new);
 355	kfree(new);
 356	if (IS_ERR(opt))
 357		return PTR_ERR(opt);
 358
 359	/* routing header option needs extra check */
 360	err = -EINVAL;
 361	if (optname == IPV6_RTHDR && opt && opt->srcrt) {
 362		struct ipv6_rt_hdr *rthdr = opt->srcrt;
 363		switch (rthdr->type) {
 364#if IS_ENABLED(CONFIG_IPV6_MIP6)
 365		case IPV6_SRCRT_TYPE_2:
 366			if (rthdr->hdrlen != 2 || rthdr->segments_left != 1)
 367				goto sticky_done;
 368			break;
 369#endif
 370		case IPV6_SRCRT_TYPE_4:
 371		{
 372			struct ipv6_sr_hdr *srh =
 373				(struct ipv6_sr_hdr *)opt->srcrt;
 374
 375			if (!seg6_validate_srh(srh, optlen, false))
 376				goto sticky_done;
 377			break;
 378		}
 379		default:
 380			goto sticky_done;
 381		}
 382	}
 383
 384	err = 0;
 385	opt = ipv6_update_options(sk, opt);
 386sticky_done:
 387	if (opt) {
 388		atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 389		txopt_put(opt);
 390	}
 391	return err;
 392}
 393
 394int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
 395		       sockptr_t optval, unsigned int optlen)
 396{
 397	struct ipv6_pinfo *np = inet6_sk(sk);
 398	struct net *net = sock_net(sk);
 399	int val, valbool;
 400	int retv = -ENOPROTOOPT;
 401	bool needs_rtnl = setsockopt_needs_rtnl(optname);
 402
 403	if (sockptr_is_null(optval))
 404		val = 0;
 405	else {
 406		if (optlen >= sizeof(int)) {
 407			if (copy_from_sockptr(&val, optval, sizeof(val)))
 408				return -EFAULT;
 409		} else
 410			val = 0;
 411	}
 412
 413	valbool = (val != 0);
 414
 415	if (ip6_mroute_opt(optname))
 416		return ip6_mroute_setsockopt(sk, optname, optval, optlen);
 417
 418	/* Handle options that can be set without locking the socket. */
 419	switch (optname) {
 420	case IPV6_UNICAST_HOPS:
 421		if (optlen < sizeof(int))
 422			return -EINVAL;
 423		if (val > 255 || val < -1)
 424			return -EINVAL;
 425		WRITE_ONCE(np->hop_limit, val);
 426		return 0;
 427	case IPV6_MULTICAST_LOOP:
 428		if (optlen < sizeof(int))
 429			return -EINVAL;
 430		if (val != valbool)
 431			return -EINVAL;
 432		inet6_assign_bit(MC6_LOOP, sk, valbool);
 433		return 0;
 434	case IPV6_MULTICAST_HOPS:
 435		if (sk->sk_type == SOCK_STREAM)
 436			return retv;
 437		if (optlen < sizeof(int))
 438			return -EINVAL;
 439		if (val > 255 || val < -1)
 440			return -EINVAL;
 441		WRITE_ONCE(np->mcast_hops,
 442			   val == -1 ? IPV6_DEFAULT_MCASTHOPS : val);
 443		return 0;
 444	case IPV6_MTU:
 445		if (optlen < sizeof(int))
 446			return -EINVAL;
 447		if (val && val < IPV6_MIN_MTU)
 448			return -EINVAL;
 449		WRITE_ONCE(np->frag_size, val);
 450		return 0;
 451	case IPV6_MINHOPCOUNT:
 452		if (optlen < sizeof(int))
 453			return -EINVAL;
 454		if (val < 0 || val > 255)
 455			return -EINVAL;
 456
 457		if (val)
 458			static_branch_enable(&ip6_min_hopcount);
 459
 460		/* tcp_v6_err() and tcp_v6_rcv() might read min_hopcount
 461		 * while we are changing it.
 462		 */
 463		WRITE_ONCE(np->min_hopcount, val);
 464		return 0;
 465	case IPV6_RECVERR_RFC4884:
 466		if (optlen < sizeof(int))
 467			return -EINVAL;
 468		if (val < 0 || val > 1)
 469			return -EINVAL;
 470		inet6_assign_bit(RECVERR6_RFC4884, sk, valbool);
 471		return 0;
 472	case IPV6_MULTICAST_ALL:
 473		if (optlen < sizeof(int))
 474			return -EINVAL;
 475		inet6_assign_bit(MC6_ALL, sk, valbool);
 476		return 0;
 477	case IPV6_AUTOFLOWLABEL:
 478		inet6_assign_bit(AUTOFLOWLABEL, sk, valbool);
 479		inet6_set_bit(AUTOFLOWLABEL_SET, sk);
 480		return 0;
 481	case IPV6_DONTFRAG:
 482		inet6_assign_bit(DONTFRAG, sk, valbool);
 483		return 0;
 484	case IPV6_RECVERR:
 485		if (optlen < sizeof(int))
 486			return -EINVAL;
 487		inet6_assign_bit(RECVERR6, sk, valbool);
 488		if (!val)
 489			skb_errqueue_purge(&sk->sk_error_queue);
 490		return 0;
 491	case IPV6_ROUTER_ALERT_ISOLATE:
 492		if (optlen < sizeof(int))
 493			return -EINVAL;
 494		inet6_assign_bit(RTALERT_ISOLATE, sk, valbool);
 495		return 0;
 496	case IPV6_MTU_DISCOVER:
 497		if (optlen < sizeof(int))
 498			return -EINVAL;
 499		if (val < IPV6_PMTUDISC_DONT || val > IPV6_PMTUDISC_OMIT)
 500			return -EINVAL;
 501		WRITE_ONCE(np->pmtudisc, val);
 502		return 0;
 503	case IPV6_FLOWINFO_SEND:
 504		if (optlen < sizeof(int))
 505			return -EINVAL;
 506		inet6_assign_bit(SNDFLOW, sk, valbool);
 507		return 0;
 508	case IPV6_ADDR_PREFERENCES:
 509		if (optlen < sizeof(int))
 510			return -EINVAL;
 511		return ip6_sock_set_addr_preferences(sk, val);
 512	case IPV6_MULTICAST_IF:
 513		if (sk->sk_type == SOCK_STREAM)
 514			return -ENOPROTOOPT;
 515		if (optlen < sizeof(int))
 516			return -EINVAL;
 517		if (val) {
 518			struct net_device *dev;
 519			int bound_dev_if, midx;
 520
 521			rcu_read_lock();
 522
 523			dev = dev_get_by_index_rcu(net, val);
 524			if (!dev) {
 525				rcu_read_unlock();
 526				return -ENODEV;
 527			}
 528			midx = l3mdev_master_ifindex_rcu(dev);
 529
 530			rcu_read_unlock();
 531
 532			bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
 533			if (bound_dev_if &&
 534			    bound_dev_if != val &&
 535			    (!midx || midx != bound_dev_if))
 536				return -EINVAL;
 537		}
 538		WRITE_ONCE(np->mcast_oif, val);
 539		return 0;
 540	case IPV6_UNICAST_IF:
 541	{
 542		struct net_device *dev;
 543		int ifindex;
 544
 545		if (optlen != sizeof(int))
 546			return -EINVAL;
 547
 548		ifindex = (__force int)ntohl((__force __be32)val);
 549		if (!ifindex) {
 550			WRITE_ONCE(np->ucast_oif, 0);
 551			return 0;
 552		}
 553
 554		dev = dev_get_by_index(net, ifindex);
 555		if (!dev)
 556			return -EADDRNOTAVAIL;
 557		dev_put(dev);
 558
 559		if (READ_ONCE(sk->sk_bound_dev_if))
 560			return -EINVAL;
 561
 562		WRITE_ONCE(np->ucast_oif, ifindex);
 563		return 0;
 564	}
 565	}
 566	if (needs_rtnl)
 567		rtnl_lock();
 568	sockopt_lock_sock(sk);
 569
 570	/* Another thread has converted the socket into IPv4 with
 571	 * IPV6_ADDRFORM concurrently.
 572	 */
 573	if (unlikely(sk->sk_family != AF_INET6))
 574		goto unlock;
 575
 576	switch (optname) {
 577
 578	case IPV6_ADDRFORM:
 579		if (optlen < sizeof(int))
 580			goto e_inval;
 581		if (val == PF_INET) {
 582			if (sk->sk_type == SOCK_RAW)
 583				break;
 584
 585			if (sk->sk_protocol == IPPROTO_UDP ||
 586			    sk->sk_protocol == IPPROTO_UDPLITE) {
 587				struct udp_sock *up = udp_sk(sk);
 588				if (up->pending == AF_INET6) {
 589					retv = -EBUSY;
 590					break;
 591				}
 592			} else if (sk->sk_protocol == IPPROTO_TCP) {
 593				if (sk->sk_prot != &tcpv6_prot) {
 594					retv = -EBUSY;
 595					break;
 596				}
 597			} else {
 598				break;
 599			}
 600
 601			if (sk->sk_state != TCP_ESTABLISHED) {
 602				retv = -ENOTCONN;
 603				break;
 604			}
 605
 606			if (ipv6_only_sock(sk) ||
 607			    !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) {
 608				retv = -EADDRNOTAVAIL;
 609				break;
 610			}
 611
 612			__ipv6_sock_mc_close(sk);
 613			__ipv6_sock_ac_close(sk);
 614
 
 
 
 
 
 
 
 615			if (sk->sk_protocol == IPPROTO_TCP) {
 616				struct inet_connection_sock *icsk = inet_csk(sk);
 617
 618				sock_prot_inuse_add(net, sk->sk_prot, -1);
 619				sock_prot_inuse_add(net, &tcp_prot, 1);
 620
 621				/* Paired with READ_ONCE(sk->sk_prot) in inet6_stream_ops */
 622				WRITE_ONCE(sk->sk_prot, &tcp_prot);
 623				/* Paired with READ_ONCE() in tcp_(get|set)sockopt() */
 624				WRITE_ONCE(icsk->icsk_af_ops, &ipv4_specific);
 625				WRITE_ONCE(sk->sk_socket->ops, &inet_stream_ops);
 626				WRITE_ONCE(sk->sk_family, PF_INET);
 627				tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
 628			} else {
 629				struct proto *prot = &udp_prot;
 630
 631				if (sk->sk_protocol == IPPROTO_UDPLITE)
 632					prot = &udplite_prot;
 633
 634				sock_prot_inuse_add(net, sk->sk_prot, -1);
 635				sock_prot_inuse_add(net, prot, 1);
 636
 637				/* Paired with READ_ONCE(sk->sk_prot) in inet6_dgram_ops */
 638				WRITE_ONCE(sk->sk_prot, prot);
 639				WRITE_ONCE(sk->sk_socket->ops, &inet_dgram_ops);
 640				WRITE_ONCE(sk->sk_family, PF_INET);
 641			}
 642
 643			/* Disable all options not to allocate memory anymore,
 644			 * but there is still a race.  See the lockless path
 645			 * in udpv6_sendmsg() and ipv6_local_rxpmtu().
 646			 */
 647			np->rxopt.all = 0;
 648
 649			inet6_cleanup_sock(sk);
 650
 
 
 
 
 
 651			module_put(THIS_MODULE);
 652			retv = 0;
 653			break;
 654		}
 655		goto e_inval;
 656
 657	case IPV6_V6ONLY:
 658		if (optlen < sizeof(int) ||
 659		    inet_sk(sk)->inet_num)
 660			goto e_inval;
 661		sk->sk_ipv6only = valbool;
 662		retv = 0;
 663		break;
 664
 665	case IPV6_RECVPKTINFO:
 666		if (optlen < sizeof(int))
 667			goto e_inval;
 668		np->rxopt.bits.rxinfo = valbool;
 669		retv = 0;
 670		break;
 671
 672	case IPV6_2292PKTINFO:
 673		if (optlen < sizeof(int))
 674			goto e_inval;
 675		np->rxopt.bits.rxoinfo = valbool;
 676		retv = 0;
 677		break;
 678
 679	case IPV6_RECVHOPLIMIT:
 680		if (optlen < sizeof(int))
 681			goto e_inval;
 682		np->rxopt.bits.rxhlim = valbool;
 683		retv = 0;
 684		break;
 685
 686	case IPV6_2292HOPLIMIT:
 687		if (optlen < sizeof(int))
 688			goto e_inval;
 689		np->rxopt.bits.rxohlim = valbool;
 690		retv = 0;
 691		break;
 692
 693	case IPV6_RECVRTHDR:
 694		if (optlen < sizeof(int))
 695			goto e_inval;
 696		np->rxopt.bits.srcrt = valbool;
 697		retv = 0;
 698		break;
 699
 700	case IPV6_2292RTHDR:
 701		if (optlen < sizeof(int))
 702			goto e_inval;
 703		np->rxopt.bits.osrcrt = valbool;
 704		retv = 0;
 705		break;
 706
 707	case IPV6_RECVHOPOPTS:
 708		if (optlen < sizeof(int))
 709			goto e_inval;
 710		np->rxopt.bits.hopopts = valbool;
 711		retv = 0;
 712		break;
 713
 714	case IPV6_2292HOPOPTS:
 715		if (optlen < sizeof(int))
 716			goto e_inval;
 717		np->rxopt.bits.ohopopts = valbool;
 718		retv = 0;
 719		break;
 720
 721	case IPV6_RECVDSTOPTS:
 722		if (optlen < sizeof(int))
 723			goto e_inval;
 724		np->rxopt.bits.dstopts = valbool;
 725		retv = 0;
 726		break;
 727
 728	case IPV6_2292DSTOPTS:
 729		if (optlen < sizeof(int))
 730			goto e_inval;
 731		np->rxopt.bits.odstopts = valbool;
 732		retv = 0;
 733		break;
 734
 735	case IPV6_TCLASS:
 736		if (optlen < sizeof(int))
 737			goto e_inval;
 738		if (val < -1 || val > 0xff)
 739			goto e_inval;
 740		/* RFC 3542, 6.5: default traffic class of 0x0 */
 741		if (val == -1)
 742			val = 0;
 743		if (sk->sk_type == SOCK_STREAM) {
 744			val &= ~INET_ECN_MASK;
 745			val |= np->tclass & INET_ECN_MASK;
 746		}
 747		if (np->tclass != val) {
 748			np->tclass = val;
 749			sk_dst_reset(sk);
 750		}
 751		retv = 0;
 752		break;
 753
 754	case IPV6_RECVTCLASS:
 755		if (optlen < sizeof(int))
 756			goto e_inval;
 757		np->rxopt.bits.rxtclass = valbool;
 758		retv = 0;
 759		break;
 760
 761	case IPV6_FLOWINFO:
 762		if (optlen < sizeof(int))
 763			goto e_inval;
 764		np->rxopt.bits.rxflow = valbool;
 765		retv = 0;
 766		break;
 767
 768	case IPV6_RECVPATHMTU:
 769		if (optlen < sizeof(int))
 770			goto e_inval;
 771		np->rxopt.bits.rxpmtu = valbool;
 772		retv = 0;
 773		break;
 774
 775	case IPV6_TRANSPARENT:
 776		if (valbool && !sockopt_ns_capable(net->user_ns, CAP_NET_RAW) &&
 777		    !sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN)) {
 778			retv = -EPERM;
 779			break;
 780		}
 781		if (optlen < sizeof(int))
 782			goto e_inval;
 783		/* we don't have a separate transparent bit for IPV6 we use the one in the IPv4 socket */
 784		inet_assign_bit(TRANSPARENT, sk, valbool);
 785		retv = 0;
 786		break;
 787
 788	case IPV6_FREEBIND:
 789		if (optlen < sizeof(int))
 790			goto e_inval;
 791		/* we also don't have a separate freebind bit for IPV6 */
 792		inet_assign_bit(FREEBIND, sk, valbool);
 793		retv = 0;
 794		break;
 795
 796	case IPV6_RECVORIGDSTADDR:
 797		if (optlen < sizeof(int))
 798			goto e_inval;
 799		np->rxopt.bits.rxorigdstaddr = valbool;
 800		retv = 0;
 801		break;
 802
 803	case IPV6_HOPOPTS:
 804	case IPV6_RTHDRDSTOPTS:
 805	case IPV6_RTHDR:
 806	case IPV6_DSTOPTS:
 807		retv = ipv6_set_opt_hdr(sk, optname, optval, optlen);
 808		break;
 809
 810	case IPV6_PKTINFO:
 811	{
 812		struct in6_pktinfo pkt;
 813
 814		if (optlen == 0)
 815			goto e_inval;
 816		else if (optlen < sizeof(struct in6_pktinfo) ||
 817			 sockptr_is_null(optval))
 818			goto e_inval;
 819
 820		if (copy_from_sockptr(&pkt, optval, sizeof(pkt))) {
 821			retv = -EFAULT;
 822			break;
 823		}
 824		if (!sk_dev_equal_l3scope(sk, pkt.ipi6_ifindex))
 825			goto e_inval;
 826
 827		np->sticky_pktinfo.ipi6_ifindex = pkt.ipi6_ifindex;
 828		np->sticky_pktinfo.ipi6_addr = pkt.ipi6_addr;
 829		retv = 0;
 830		break;
 831	}
 832
 833	case IPV6_2292PKTOPTIONS:
 834	{
 835		struct ipv6_txoptions *opt = NULL;
 836		struct msghdr msg;
 837		struct flowi6 fl6;
 838		struct ipcm6_cookie ipc6;
 839
 840		memset(&fl6, 0, sizeof(fl6));
 841		fl6.flowi6_oif = sk->sk_bound_dev_if;
 842		fl6.flowi6_mark = sk->sk_mark;
 843
 844		if (optlen == 0)
 845			goto update;
 846
 847		/* 1K is probably excessive
 848		 * 1K is surely not enough, 2K per standard header is 16K.
 849		 */
 850		retv = -EINVAL;
 851		if (optlen > 64*1024)
 852			break;
 853
 854		opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL);
 855		retv = -ENOBUFS;
 856		if (!opt)
 857			break;
 858
 859		memset(opt, 0, sizeof(*opt));
 860		refcount_set(&opt->refcnt, 1);
 861		opt->tot_len = sizeof(*opt) + optlen;
 862		retv = -EFAULT;
 863		if (copy_from_sockptr(opt + 1, optval, optlen))
 864			goto done;
 865
 866		msg.msg_controllen = optlen;
 867		msg.msg_control_is_user = false;
 868		msg.msg_control = (void *)(opt+1);
 869		ipc6.opt = opt;
 870
 871		retv = ip6_datagram_send_ctl(net, sk, &msg, &fl6, &ipc6);
 872		if (retv)
 873			goto done;
 874update:
 875		retv = 0;
 876		opt = ipv6_update_options(sk, opt);
 877done:
 878		if (opt) {
 879			atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 880			txopt_put(opt);
 881		}
 882		break;
 883	}
 
 
 
 
 
 
 
 
 884
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 885	case IPV6_ADD_MEMBERSHIP:
 886	case IPV6_DROP_MEMBERSHIP:
 887	{
 888		struct ipv6_mreq mreq;
 889
 890		if (optlen < sizeof(struct ipv6_mreq))
 891			goto e_inval;
 892
 893		retv = -EPROTO;
 894		if (inet_test_bit(IS_ICSK, sk))
 895			break;
 896
 897		retv = -EFAULT;
 898		if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 899			break;
 900
 901		if (optname == IPV6_ADD_MEMBERSHIP)
 902			retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 903		else
 904			retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 905		break;
 906	}
 907	case IPV6_JOIN_ANYCAST:
 908	case IPV6_LEAVE_ANYCAST:
 909	{
 910		struct ipv6_mreq mreq;
 911
 912		if (optlen < sizeof(struct ipv6_mreq))
 913			goto e_inval;
 914
 915		retv = -EFAULT;
 916		if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 917			break;
 918
 919		if (optname == IPV6_JOIN_ANYCAST)
 920			retv = ipv6_sock_ac_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 921		else
 922			retv = ipv6_sock_ac_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 923		break;
 924	}
 
 
 
 
 
 
 
 925	case MCAST_JOIN_GROUP:
 926	case MCAST_LEAVE_GROUP:
 927		if (in_compat_syscall())
 928			retv = compat_ipv6_mcast_join_leave(sk, optname, optval,
 929							    optlen);
 930		else
 931			retv = ipv6_mcast_join_leave(sk, optname, optval,
 932						     optlen);
 933		break;
 934	case MCAST_JOIN_SOURCE_GROUP:
 935	case MCAST_LEAVE_SOURCE_GROUP:
 936	case MCAST_BLOCK_SOURCE:
 937	case MCAST_UNBLOCK_SOURCE:
 938		retv = do_ipv6_mcast_group_source(sk, optname, optval, optlen);
 939		break;
 940	case MCAST_MSFILTER:
 941		if (in_compat_syscall())
 942			retv = compat_ipv6_set_mcast_msfilter(sk, optval,
 943							      optlen);
 944		else
 945			retv = ipv6_set_mcast_msfilter(sk, optval, optlen);
 946		break;
 947	case IPV6_ROUTER_ALERT:
 948		if (optlen < sizeof(int))
 949			goto e_inval;
 950		retv = ip6_ra_control(sk, val);
 951		if (retv == 0)
 952			inet6_assign_bit(RTALERT, sk, valbool);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 953		break;
 954	case IPV6_FLOWLABEL_MGR:
 955		retv = ipv6_flowlabel_opt(sk, optval, optlen);
 956		break;
 957	case IPV6_IPSEC_POLICY:
 958	case IPV6_XFRM_POLICY:
 959		retv = -EPERM;
 960		if (!sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN))
 961			break;
 962		retv = xfrm_user_policy(sk, optname, optval, optlen);
 963		break;
 964
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 965	case IPV6_RECVFRAGSIZE:
 966		np->rxopt.bits.recvfragsize = valbool;
 967		retv = 0;
 968		break;
 
 
 
 
 
 
 
 
 969	}
 970
 971unlock:
 972	sockopt_release_sock(sk);
 973	if (needs_rtnl)
 974		rtnl_unlock();
 975
 976	return retv;
 977
 978e_inval:
 979	retv = -EINVAL;
 980	goto unlock;
 981}
 982
 983int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
 984		    unsigned int optlen)
 985{
 986	int err;
 987
 988	if (level == SOL_IP && sk->sk_type != SOCK_RAW)
 989		return udp_prot.setsockopt(sk, level, optname, optval, optlen);
 990
 991	if (level != SOL_IPV6)
 992		return -ENOPROTOOPT;
 993
 994	err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);
 995#ifdef CONFIG_NETFILTER
 996	/* we need to exclude all possible ENOPROTOOPTs except default case */
 997	if (err == -ENOPROTOOPT && optname != IPV6_IPSEC_POLICY &&
 998			optname != IPV6_XFRM_POLICY)
 999		err = nf_setsockopt(sk, PF_INET6, optname, optval, optlen);
1000#endif
1001	return err;
1002}
1003EXPORT_SYMBOL(ipv6_setsockopt);
1004
1005static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
1006				  int optname, sockptr_t optval, int len)
1007{
1008	struct ipv6_opt_hdr *hdr;
1009
1010	if (!opt)
1011		return 0;
1012
1013	switch (optname) {
1014	case IPV6_HOPOPTS:
1015		hdr = opt->hopopt;
1016		break;
1017	case IPV6_RTHDRDSTOPTS:
1018		hdr = opt->dst0opt;
1019		break;
1020	case IPV6_RTHDR:
1021		hdr = (struct ipv6_opt_hdr *)opt->srcrt;
1022		break;
1023	case IPV6_DSTOPTS:
1024		hdr = opt->dst1opt;
1025		break;
1026	default:
1027		return -EINVAL;	/* should not happen */
1028	}
1029
1030	if (!hdr)
1031		return 0;
1032
1033	len = min_t(unsigned int, len, ipv6_optlen(hdr));
1034	if (copy_to_sockptr(optval, hdr, len))
1035		return -EFAULT;
1036	return len;
1037}
1038
1039static int ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
1040			     sockptr_t optlen, int len)
1041{
1042	const int size0 = offsetof(struct group_filter, gf_slist_flex);
1043	struct group_filter gsf;
1044	int num;
1045	int err;
1046
1047	if (len < size0)
1048		return -EINVAL;
1049	if (copy_from_sockptr(&gsf, optval, size0))
1050		return -EFAULT;
1051	if (gsf.gf_group.ss_family != AF_INET6)
1052		return -EADDRNOTAVAIL;
1053	num = gsf.gf_numsrc;
1054	sockopt_lock_sock(sk);
1055	err = ip6_mc_msfget(sk, &gsf, optval, size0);
1056	if (!err) {
1057		if (num > gsf.gf_numsrc)
1058			num = gsf.gf_numsrc;
1059		len = GROUP_FILTER_SIZE(num);
1060		if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
1061		    copy_to_sockptr(optval, &gsf, size0))
1062			err = -EFAULT;
1063	}
1064	sockopt_release_sock(sk);
1065	return err;
1066}
1067
1068static int compat_ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
1069				    sockptr_t optlen, int len)
1070{
1071	const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
1072	struct compat_group_filter gf32;
1073	struct group_filter gf;
1074	int err;
1075	int num;
1076
1077	if (len < size0)
1078		return -EINVAL;
1079
1080	if (copy_from_sockptr(&gf32, optval, size0))
1081		return -EFAULT;
1082	gf.gf_interface = gf32.gf_interface;
1083	gf.gf_fmode = gf32.gf_fmode;
1084	num = gf.gf_numsrc = gf32.gf_numsrc;
1085	gf.gf_group = gf32.gf_group;
1086
1087	if (gf.gf_group.ss_family != AF_INET6)
1088		return -EADDRNOTAVAIL;
1089
1090	sockopt_lock_sock(sk);
1091	err = ip6_mc_msfget(sk, &gf, optval, size0);
1092	sockopt_release_sock(sk);
1093	if (err)
1094		return err;
1095	if (num > gf.gf_numsrc)
1096		num = gf.gf_numsrc;
1097	len = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32));
1098	if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
1099	    copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_fmode),
1100				   &gf.gf_fmode, sizeof(gf32.gf_fmode)) ||
1101	    copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_numsrc),
1102				   &gf.gf_numsrc, sizeof(gf32.gf_numsrc)))
1103		return -EFAULT;
1104	return 0;
1105}
1106
1107int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
1108		       sockptr_t optval, sockptr_t optlen)
1109{
1110	struct ipv6_pinfo *np = inet6_sk(sk);
1111	int len;
1112	int val;
1113
1114	if (ip6_mroute_opt(optname))
1115		return ip6_mroute_getsockopt(sk, optname, optval, optlen);
1116
1117	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1118		return -EFAULT;
1119	switch (optname) {
1120	case IPV6_ADDRFORM:
1121		if (sk->sk_protocol != IPPROTO_UDP &&
1122		    sk->sk_protocol != IPPROTO_UDPLITE &&
1123		    sk->sk_protocol != IPPROTO_TCP)
1124			return -ENOPROTOOPT;
1125		if (sk->sk_state != TCP_ESTABLISHED)
1126			return -ENOTCONN;
1127		val = sk->sk_family;
1128		break;
1129	case MCAST_MSFILTER:
1130		if (in_compat_syscall())
1131			return compat_ipv6_get_msfilter(sk, optval, optlen, len);
1132		return ipv6_get_msfilter(sk, optval, optlen, len);
1133	case IPV6_2292PKTOPTIONS:
1134	{
1135		struct msghdr msg;
1136		struct sk_buff *skb;
1137
1138		if (sk->sk_type != SOCK_STREAM)
1139			return -ENOPROTOOPT;
1140
1141		if (optval.is_kernel) {
1142			msg.msg_control_is_user = false;
1143			msg.msg_control = optval.kernel;
1144		} else {
1145			msg.msg_control_is_user = true;
1146			msg.msg_control_user = optval.user;
1147		}
1148		msg.msg_controllen = len;
1149		msg.msg_flags = 0;
1150
1151		sockopt_lock_sock(sk);
1152		skb = np->pktoptions;
1153		if (skb)
1154			ip6_datagram_recv_ctl(sk, &msg, skb);
1155		sockopt_release_sock(sk);
1156		if (!skb) {
1157			if (np->rxopt.bits.rxinfo) {
1158				int mcast_oif = READ_ONCE(np->mcast_oif);
1159				struct in6_pktinfo src_info;
1160
1161				src_info.ipi6_ifindex = mcast_oif ? :
1162					np->sticky_pktinfo.ipi6_ifindex;
1163				src_info.ipi6_addr = mcast_oif ? sk->sk_v6_daddr : np->sticky_pktinfo.ipi6_addr;
1164				put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
1165			}
1166			if (np->rxopt.bits.rxhlim) {
1167				int hlim = READ_ONCE(np->mcast_hops);
1168
1169				put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
1170			}
1171			if (np->rxopt.bits.rxtclass) {
1172				int tclass = (int)ip6_tclass(np->rcv_flowinfo);
1173
1174				put_cmsg(&msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
1175			}
1176			if (np->rxopt.bits.rxoinfo) {
1177				int mcast_oif = READ_ONCE(np->mcast_oif);
1178				struct in6_pktinfo src_info;
1179
1180				src_info.ipi6_ifindex = mcast_oif ? :
1181					np->sticky_pktinfo.ipi6_ifindex;
1182				src_info.ipi6_addr = mcast_oif ? sk->sk_v6_daddr :
1183								 np->sticky_pktinfo.ipi6_addr;
1184				put_cmsg(&msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
1185			}
1186			if (np->rxopt.bits.rxohlim) {
1187				int hlim = READ_ONCE(np->mcast_hops);
1188
1189				put_cmsg(&msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
1190			}
1191			if (np->rxopt.bits.rxflow) {
1192				__be32 flowinfo = np->rcv_flowinfo;
1193
1194				put_cmsg(&msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
1195			}
1196		}
1197		len -= msg.msg_controllen;
1198		return copy_to_sockptr(optlen, &len, sizeof(int));
1199	}
1200	case IPV6_MTU:
1201	{
1202		struct dst_entry *dst;
1203
1204		val = 0;
1205		rcu_read_lock();
1206		dst = __sk_dst_get(sk);
1207		if (dst)
1208			val = dst_mtu(dst);
1209		rcu_read_unlock();
1210		if (!val)
1211			return -ENOTCONN;
1212		break;
1213	}
1214
1215	case IPV6_V6ONLY:
1216		val = sk->sk_ipv6only;
1217		break;
1218
1219	case IPV6_RECVPKTINFO:
1220		val = np->rxopt.bits.rxinfo;
1221		break;
1222
1223	case IPV6_2292PKTINFO:
1224		val = np->rxopt.bits.rxoinfo;
1225		break;
1226
1227	case IPV6_RECVHOPLIMIT:
1228		val = np->rxopt.bits.rxhlim;
1229		break;
1230
1231	case IPV6_2292HOPLIMIT:
1232		val = np->rxopt.bits.rxohlim;
1233		break;
1234
1235	case IPV6_RECVRTHDR:
1236		val = np->rxopt.bits.srcrt;
1237		break;
1238
1239	case IPV6_2292RTHDR:
1240		val = np->rxopt.bits.osrcrt;
1241		break;
1242
1243	case IPV6_HOPOPTS:
1244	case IPV6_RTHDRDSTOPTS:
1245	case IPV6_RTHDR:
1246	case IPV6_DSTOPTS:
1247	{
1248		struct ipv6_txoptions *opt;
1249
1250		sockopt_lock_sock(sk);
1251		opt = rcu_dereference_protected(np->opt,
1252						lockdep_sock_is_held(sk));
1253		len = ipv6_getsockopt_sticky(sk, opt, optname, optval, len);
1254		sockopt_release_sock(sk);
1255		/* check if ipv6_getsockopt_sticky() returns err code */
1256		if (len < 0)
1257			return len;
1258		return copy_to_sockptr(optlen, &len, sizeof(int));
1259	}
1260
1261	case IPV6_RECVHOPOPTS:
1262		val = np->rxopt.bits.hopopts;
1263		break;
1264
1265	case IPV6_2292HOPOPTS:
1266		val = np->rxopt.bits.ohopopts;
1267		break;
1268
1269	case IPV6_RECVDSTOPTS:
1270		val = np->rxopt.bits.dstopts;
1271		break;
1272
1273	case IPV6_2292DSTOPTS:
1274		val = np->rxopt.bits.odstopts;
1275		break;
1276
1277	case IPV6_TCLASS:
1278		val = np->tclass;
1279		break;
1280
1281	case IPV6_RECVTCLASS:
1282		val = np->rxopt.bits.rxtclass;
1283		break;
1284
1285	case IPV6_FLOWINFO:
1286		val = np->rxopt.bits.rxflow;
1287		break;
1288
1289	case IPV6_RECVPATHMTU:
1290		val = np->rxopt.bits.rxpmtu;
1291		break;
1292
1293	case IPV6_PATHMTU:
1294	{
1295		struct dst_entry *dst;
1296		struct ip6_mtuinfo mtuinfo;
1297
1298		if (len < sizeof(mtuinfo))
1299			return -EINVAL;
1300
1301		len = sizeof(mtuinfo);
1302		memset(&mtuinfo, 0, sizeof(mtuinfo));
1303
1304		rcu_read_lock();
1305		dst = __sk_dst_get(sk);
1306		if (dst)
1307			mtuinfo.ip6m_mtu = dst_mtu(dst);
1308		rcu_read_unlock();
1309		if (!mtuinfo.ip6m_mtu)
1310			return -ENOTCONN;
1311
1312		if (copy_to_sockptr(optlen, &len, sizeof(int)))
1313			return -EFAULT;
1314		if (copy_to_sockptr(optval, &mtuinfo, len))
1315			return -EFAULT;
1316
1317		return 0;
1318	}
1319
1320	case IPV6_TRANSPARENT:
1321		val = inet_test_bit(TRANSPARENT, sk);
1322		break;
1323
1324	case IPV6_FREEBIND:
1325		val = inet_test_bit(FREEBIND, sk);
1326		break;
1327
1328	case IPV6_RECVORIGDSTADDR:
1329		val = np->rxopt.bits.rxorigdstaddr;
1330		break;
1331
1332	case IPV6_UNICAST_HOPS:
1333	case IPV6_MULTICAST_HOPS:
1334	{
1335		struct dst_entry *dst;
1336
1337		if (optname == IPV6_UNICAST_HOPS)
1338			val = READ_ONCE(np->hop_limit);
1339		else
1340			val = READ_ONCE(np->mcast_hops);
1341
1342		if (val < 0) {
1343			rcu_read_lock();
1344			dst = __sk_dst_get(sk);
1345			if (dst)
1346				val = ip6_dst_hoplimit(dst);
1347			rcu_read_unlock();
1348		}
1349
1350		if (val < 0)
1351			val = READ_ONCE(sock_net(sk)->ipv6.devconf_all->hop_limit);
1352		break;
1353	}
1354
1355	case IPV6_MULTICAST_LOOP:
1356		val = inet6_test_bit(MC6_LOOP, sk);
1357		break;
1358
1359	case IPV6_MULTICAST_IF:
1360		val = READ_ONCE(np->mcast_oif);
1361		break;
1362
1363	case IPV6_MULTICAST_ALL:
1364		val = inet6_test_bit(MC6_ALL, sk);
1365		break;
1366
1367	case IPV6_UNICAST_IF:
1368		val = (__force int)htonl((__u32) READ_ONCE(np->ucast_oif));
1369		break;
1370
1371	case IPV6_MTU_DISCOVER:
1372		val = READ_ONCE(np->pmtudisc);
1373		break;
1374
1375	case IPV6_RECVERR:
1376		val = inet6_test_bit(RECVERR6, sk);
1377		break;
1378
1379	case IPV6_FLOWINFO_SEND:
1380		val = inet6_test_bit(SNDFLOW, sk);
1381		break;
1382
1383	case IPV6_FLOWLABEL_MGR:
1384	{
1385		struct in6_flowlabel_req freq;
1386		int flags;
1387
1388		if (len < sizeof(freq))
1389			return -EINVAL;
1390
1391		if (copy_from_sockptr(&freq, optval, sizeof(freq)))
1392			return -EFAULT;
1393
1394		if (freq.flr_action != IPV6_FL_A_GET)
1395			return -EINVAL;
1396
1397		len = sizeof(freq);
1398		flags = freq.flr_flags;
1399
1400		memset(&freq, 0, sizeof(freq));
1401
1402		val = ipv6_flowlabel_opt_get(sk, &freq, flags);
1403		if (val < 0)
1404			return val;
1405
1406		if (copy_to_sockptr(optlen, &len, sizeof(int)))
1407			return -EFAULT;
1408		if (copy_to_sockptr(optval, &freq, len))
1409			return -EFAULT;
1410
1411		return 0;
1412	}
1413
1414	case IPV6_ADDR_PREFERENCES:
1415		{
1416		u8 srcprefs = READ_ONCE(np->srcprefs);
1417		val = 0;
1418
1419		if (srcprefs & IPV6_PREFER_SRC_TMP)
1420			val |= IPV6_PREFER_SRC_TMP;
1421		else if (srcprefs & IPV6_PREFER_SRC_PUBLIC)
1422			val |= IPV6_PREFER_SRC_PUBLIC;
1423		else {
1424			/* XXX: should we return system default? */
1425			val |= IPV6_PREFER_SRC_PUBTMP_DEFAULT;
1426		}
1427
1428		if (srcprefs & IPV6_PREFER_SRC_COA)
1429			val |= IPV6_PREFER_SRC_COA;
1430		else
1431			val |= IPV6_PREFER_SRC_HOME;
1432		break;
1433		}
1434	case IPV6_MINHOPCOUNT:
1435		val = READ_ONCE(np->min_hopcount);
1436		break;
1437
1438	case IPV6_DONTFRAG:
1439		val = inet6_test_bit(DONTFRAG, sk);
1440		break;
1441
1442	case IPV6_AUTOFLOWLABEL:
1443		val = ip6_autoflowlabel(sock_net(sk), sk);
1444		break;
1445
1446	case IPV6_RECVFRAGSIZE:
1447		val = np->rxopt.bits.recvfragsize;
1448		break;
1449
1450	case IPV6_ROUTER_ALERT:
1451		val = inet6_test_bit(RTALERT, sk);
1452		break;
1453
1454	case IPV6_ROUTER_ALERT_ISOLATE:
1455		val = inet6_test_bit(RTALERT_ISOLATE, sk);
1456		break;
1457
1458	case IPV6_RECVERR_RFC4884:
1459		val = inet6_test_bit(RECVERR6_RFC4884, sk);
1460		break;
1461
1462	default:
1463		return -ENOPROTOOPT;
1464	}
1465	len = min_t(unsigned int, sizeof(int), len);
1466	if (copy_to_sockptr(optlen, &len, sizeof(int)))
1467		return -EFAULT;
1468	if (copy_to_sockptr(optval, &val, len))
1469		return -EFAULT;
1470	return 0;
1471}
1472
1473int ipv6_getsockopt(struct sock *sk, int level, int optname,
1474		    char __user *optval, int __user *optlen)
1475{
1476	int err;
1477
1478	if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1479		return udp_prot.getsockopt(sk, level, optname, optval, optlen);
1480
1481	if (level != SOL_IPV6)
1482		return -ENOPROTOOPT;
1483
1484	err = do_ipv6_getsockopt(sk, level, optname,
1485				 USER_SOCKPTR(optval), USER_SOCKPTR(optlen));
1486#ifdef CONFIG_NETFILTER
1487	/* we need to exclude all possible ENOPROTOOPTs except default case */
1488	if (err == -ENOPROTOOPT && optname != IPV6_2292PKTOPTIONS) {
1489		int len;
1490
1491		if (get_user(len, optlen))
1492			return -EFAULT;
1493
1494		err = nf_getsockopt(sk, PF_INET6, optname, optval, &len);
1495		if (err >= 0)
1496			err = put_user(len, optlen);
1497	}
1498#endif
1499	return err;
1500}
1501EXPORT_SYMBOL(ipv6_getsockopt);
v6.2
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *	IPv6 BSD socket options interface
   4 *	Linux INET6 implementation
   5 *
   6 *	Authors:
   7 *	Pedro Roque		<roque@di.fc.ul.pt>
   8 *
   9 *	Based on linux/net/ipv4/ip_sockglue.c
  10 *
  11 *	FIXME: Make the setsockopt code POSIX compliant: That is
  12 *
  13 *	o	Truncate getsockopt returns
  14 *	o	Return an optlen of the truncated length if need be
  15 *
  16 *	Changes:
  17 *	David L Stevens <dlstevens@us.ibm.com>:
  18 *		- added multicast source filtering API for MLDv2
  19 */
  20
  21#include <linux/module.h>
  22#include <linux/capability.h>
  23#include <linux/errno.h>
  24#include <linux/types.h>
  25#include <linux/socket.h>
  26#include <linux/sockios.h>
  27#include <linux/net.h>
  28#include <linux/in6.h>
  29#include <linux/mroute6.h>
  30#include <linux/netdevice.h>
  31#include <linux/if_arp.h>
  32#include <linux/init.h>
  33#include <linux/sysctl.h>
  34#include <linux/netfilter.h>
  35#include <linux/slab.h>
  36
  37#include <net/sock.h>
  38#include <net/snmp.h>
  39#include <net/ipv6.h>
  40#include <net/ndisc.h>
  41#include <net/protocol.h>
  42#include <net/transp_v6.h>
  43#include <net/ip6_route.h>
  44#include <net/addrconf.h>
  45#include <net/inet_common.h>
  46#include <net/tcp.h>
  47#include <net/udp.h>
  48#include <net/udplite.h>
  49#include <net/xfrm.h>
  50#include <net/compat.h>
  51#include <net/seg6.h>
  52
  53#include <linux/uaccess.h>
  54
  55struct ip6_ra_chain *ip6_ra_chain;
  56DEFINE_RWLOCK(ip6_ra_lock);
  57
  58DEFINE_STATIC_KEY_FALSE(ip6_min_hopcount);
  59
  60int ip6_ra_control(struct sock *sk, int sel)
  61{
  62	struct ip6_ra_chain *ra, *new_ra, **rap;
  63
  64	/* RA packet may be delivered ONLY to IPPROTO_RAW socket */
  65	if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num != IPPROTO_RAW)
  66		return -ENOPROTOOPT;
  67
  68	new_ra = (sel >= 0) ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
  69	if (sel >= 0 && !new_ra)
  70		return -ENOMEM;
  71
  72	write_lock_bh(&ip6_ra_lock);
  73	for (rap = &ip6_ra_chain; (ra = *rap) != NULL; rap = &ra->next) {
  74		if (ra->sk == sk) {
  75			if (sel >= 0) {
  76				write_unlock_bh(&ip6_ra_lock);
  77				kfree(new_ra);
  78				return -EADDRINUSE;
  79			}
  80
  81			*rap = ra->next;
  82			write_unlock_bh(&ip6_ra_lock);
  83
  84			sock_put(sk);
  85			kfree(ra);
  86			return 0;
  87		}
  88	}
  89	if (!new_ra) {
  90		write_unlock_bh(&ip6_ra_lock);
  91		return -ENOBUFS;
  92	}
  93	new_ra->sk = sk;
  94	new_ra->sel = sel;
  95	new_ra->next = ra;
  96	*rap = new_ra;
  97	sock_hold(sk);
  98	write_unlock_bh(&ip6_ra_lock);
  99	return 0;
 100}
 101
 102struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
 103					   struct ipv6_txoptions *opt)
 104{
 105	if (inet_sk(sk)->is_icsk) {
 106		if (opt &&
 107		    !((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) &&
 108		    inet_sk(sk)->inet_daddr != LOOPBACK4_IPV6) {
 109			struct inet_connection_sock *icsk = inet_csk(sk);
 110			icsk->icsk_ext_hdr_len = opt->opt_flen + opt->opt_nflen;
 111			icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
 112		}
 113	}
 114	opt = xchg((__force struct ipv6_txoptions **)&inet6_sk(sk)->opt,
 115		   opt);
 116	sk_dst_reset(sk);
 117
 118	return opt;
 119}
 120
 121static bool setsockopt_needs_rtnl(int optname)
 122{
 123	switch (optname) {
 124	case IPV6_ADDRFORM:
 125	case IPV6_ADD_MEMBERSHIP:
 126	case IPV6_DROP_MEMBERSHIP:
 127	case IPV6_JOIN_ANYCAST:
 128	case IPV6_LEAVE_ANYCAST:
 129	case MCAST_JOIN_GROUP:
 130	case MCAST_LEAVE_GROUP:
 131	case MCAST_JOIN_SOURCE_GROUP:
 132	case MCAST_LEAVE_SOURCE_GROUP:
 133	case MCAST_BLOCK_SOURCE:
 134	case MCAST_UNBLOCK_SOURCE:
 135	case MCAST_MSFILTER:
 136		return true;
 137	}
 138	return false;
 139}
 140
 141static int copy_group_source_from_sockptr(struct group_source_req *greqs,
 142		sockptr_t optval, int optlen)
 143{
 144	if (in_compat_syscall()) {
 145		struct compat_group_source_req gr32;
 146
 147		if (optlen < sizeof(gr32))
 148			return -EINVAL;
 149		if (copy_from_sockptr(&gr32, optval, sizeof(gr32)))
 150			return -EFAULT;
 151		greqs->gsr_interface = gr32.gsr_interface;
 152		greqs->gsr_group = gr32.gsr_group;
 153		greqs->gsr_source = gr32.gsr_source;
 154	} else {
 155		if (optlen < sizeof(*greqs))
 156			return -EINVAL;
 157		if (copy_from_sockptr(greqs, optval, sizeof(*greqs)))
 158			return -EFAULT;
 159	}
 160
 161	return 0;
 162}
 163
 164static int do_ipv6_mcast_group_source(struct sock *sk, int optname,
 165		sockptr_t optval, int optlen)
 166{
 167	struct group_source_req greqs;
 168	int omode, add;
 169	int ret;
 170
 171	ret = copy_group_source_from_sockptr(&greqs, optval, optlen);
 172	if (ret)
 173		return ret;
 174
 175	if (greqs.gsr_group.ss_family != AF_INET6 ||
 176	    greqs.gsr_source.ss_family != AF_INET6)
 177		return -EADDRNOTAVAIL;
 178
 179	if (optname == MCAST_BLOCK_SOURCE) {
 180		omode = MCAST_EXCLUDE;
 181		add = 1;
 182	} else if (optname == MCAST_UNBLOCK_SOURCE) {
 183		omode = MCAST_EXCLUDE;
 184		add = 0;
 185	} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
 186		struct sockaddr_in6 *psin6;
 187		int retv;
 188
 189		psin6 = (struct sockaddr_in6 *)&greqs.gsr_group;
 190		retv = ipv6_sock_mc_join_ssm(sk, greqs.gsr_interface,
 191					     &psin6->sin6_addr,
 192					     MCAST_INCLUDE);
 193		/* prior join w/ different source is ok */
 194		if (retv && retv != -EADDRINUSE)
 195			return retv;
 196		omode = MCAST_INCLUDE;
 197		add = 1;
 198	} else /* MCAST_LEAVE_SOURCE_GROUP */ {
 199		omode = MCAST_INCLUDE;
 200		add = 0;
 201	}
 202	return ip6_mc_source(add, omode, sk, &greqs);
 203}
 204
 205static int ipv6_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
 206		int optlen)
 207{
 208	struct group_filter *gsf;
 209	int ret;
 210
 211	if (optlen < GROUP_FILTER_SIZE(0))
 212		return -EINVAL;
 213	if (optlen > READ_ONCE(sysctl_optmem_max))
 214		return -ENOBUFS;
 215
 216	gsf = memdup_sockptr(optval, optlen);
 217	if (IS_ERR(gsf))
 218		return PTR_ERR(gsf);
 219
 220	/* numsrc >= (4G-140)/128 overflow in 32 bits */
 221	ret = -ENOBUFS;
 222	if (gsf->gf_numsrc >= 0x1ffffffU ||
 223	    gsf->gf_numsrc > sysctl_mld_max_msf)
 224		goto out_free_gsf;
 225
 226	ret = -EINVAL;
 227	if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen)
 228		goto out_free_gsf;
 229
 230	ret = ip6_mc_msfilter(sk, gsf, gsf->gf_slist_flex);
 231out_free_gsf:
 232	kfree(gsf);
 233	return ret;
 234}
 235
 236static int compat_ipv6_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
 237		int optlen)
 238{
 239	const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
 240	struct compat_group_filter *gf32;
 241	void *p;
 242	int ret;
 243	int n;
 244
 245	if (optlen < size0)
 246		return -EINVAL;
 247	if (optlen > READ_ONCE(sysctl_optmem_max) - 4)
 248		return -ENOBUFS;
 249
 250	p = kmalloc(optlen + 4, GFP_KERNEL);
 251	if (!p)
 252		return -ENOMEM;
 253
 254	gf32 = p + 4; /* we want ->gf_group and ->gf_slist_flex aligned */
 255	ret = -EFAULT;
 256	if (copy_from_sockptr(gf32, optval, optlen))
 257		goto out_free_p;
 258
 259	/* numsrc >= (4G-140)/128 overflow in 32 bits */
 260	ret = -ENOBUFS;
 261	n = gf32->gf_numsrc;
 262	if (n >= 0x1ffffffU || n > sysctl_mld_max_msf)
 263		goto out_free_p;
 264
 265	ret = -EINVAL;
 266	if (offsetof(struct compat_group_filter, gf_slist_flex[n]) > optlen)
 267		goto out_free_p;
 268
 269	ret = ip6_mc_msfilter(sk, &(struct group_filter){
 270			.gf_interface = gf32->gf_interface,
 271			.gf_group = gf32->gf_group,
 272			.gf_fmode = gf32->gf_fmode,
 273			.gf_numsrc = gf32->gf_numsrc}, gf32->gf_slist_flex);
 274
 275out_free_p:
 276	kfree(p);
 277	return ret;
 278}
 279
 280static int ipv6_mcast_join_leave(struct sock *sk, int optname,
 281		sockptr_t optval, int optlen)
 282{
 283	struct sockaddr_in6 *psin6;
 284	struct group_req greq;
 285
 286	if (optlen < sizeof(greq))
 287		return -EINVAL;
 288	if (copy_from_sockptr(&greq, optval, sizeof(greq)))
 289		return -EFAULT;
 290
 291	if (greq.gr_group.ss_family != AF_INET6)
 292		return -EADDRNOTAVAIL;
 293	psin6 = (struct sockaddr_in6 *)&greq.gr_group;
 294	if (optname == MCAST_JOIN_GROUP)
 295		return ipv6_sock_mc_join(sk, greq.gr_interface,
 296					 &psin6->sin6_addr);
 297	return ipv6_sock_mc_drop(sk, greq.gr_interface, &psin6->sin6_addr);
 298}
 299
 300static int compat_ipv6_mcast_join_leave(struct sock *sk, int optname,
 301		sockptr_t optval, int optlen)
 302{
 303	struct compat_group_req gr32;
 304	struct sockaddr_in6 *psin6;
 305
 306	if (optlen < sizeof(gr32))
 307		return -EINVAL;
 308	if (copy_from_sockptr(&gr32, optval, sizeof(gr32)))
 309		return -EFAULT;
 310
 311	if (gr32.gr_group.ss_family != AF_INET6)
 312		return -EADDRNOTAVAIL;
 313	psin6 = (struct sockaddr_in6 *)&gr32.gr_group;
 314	if (optname == MCAST_JOIN_GROUP)
 315		return ipv6_sock_mc_join(sk, gr32.gr_interface,
 316					&psin6->sin6_addr);
 317	return ipv6_sock_mc_drop(sk, gr32.gr_interface, &psin6->sin6_addr);
 318}
 319
 320static int ipv6_set_opt_hdr(struct sock *sk, int optname, sockptr_t optval,
 321		int optlen)
 322{
 323	struct ipv6_pinfo *np = inet6_sk(sk);
 324	struct ipv6_opt_hdr *new = NULL;
 325	struct net *net = sock_net(sk);
 326	struct ipv6_txoptions *opt;
 327	int err;
 328
 329	/* hop-by-hop / destination options are privileged option */
 330	if (optname != IPV6_RTHDR && !sockopt_ns_capable(net->user_ns, CAP_NET_RAW))
 331		return -EPERM;
 332
 333	/* remove any sticky options header with a zero option
 334	 * length, per RFC3542.
 335	 */
 336	if (optlen > 0) {
 337		if (sockptr_is_null(optval))
 338			return -EINVAL;
 339		if (optlen < sizeof(struct ipv6_opt_hdr) ||
 340		    optlen & 0x7 ||
 341		    optlen > 8 * 255)
 342			return -EINVAL;
 343
 344		new = memdup_sockptr(optval, optlen);
 345		if (IS_ERR(new))
 346			return PTR_ERR(new);
 347		if (unlikely(ipv6_optlen(new) > optlen)) {
 348			kfree(new);
 349			return -EINVAL;
 350		}
 351	}
 352
 353	opt = rcu_dereference_protected(np->opt, lockdep_sock_is_held(sk));
 354	opt = ipv6_renew_options(sk, opt, optname, new);
 355	kfree(new);
 356	if (IS_ERR(opt))
 357		return PTR_ERR(opt);
 358
 359	/* routing header option needs extra check */
 360	err = -EINVAL;
 361	if (optname == IPV6_RTHDR && opt && opt->srcrt) {
 362		struct ipv6_rt_hdr *rthdr = opt->srcrt;
 363		switch (rthdr->type) {
 364#if IS_ENABLED(CONFIG_IPV6_MIP6)
 365		case IPV6_SRCRT_TYPE_2:
 366			if (rthdr->hdrlen != 2 || rthdr->segments_left != 1)
 367				goto sticky_done;
 368			break;
 369#endif
 370		case IPV6_SRCRT_TYPE_4:
 371		{
 372			struct ipv6_sr_hdr *srh =
 373				(struct ipv6_sr_hdr *)opt->srcrt;
 374
 375			if (!seg6_validate_srh(srh, optlen, false))
 376				goto sticky_done;
 377			break;
 378		}
 379		default:
 380			goto sticky_done;
 381		}
 382	}
 383
 384	err = 0;
 385	opt = ipv6_update_options(sk, opt);
 386sticky_done:
 387	if (opt) {
 388		atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 389		txopt_put(opt);
 390	}
 391	return err;
 392}
 393
 394int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
 395		       sockptr_t optval, unsigned int optlen)
 396{
 397	struct ipv6_pinfo *np = inet6_sk(sk);
 398	struct net *net = sock_net(sk);
 399	int val, valbool;
 400	int retv = -ENOPROTOOPT;
 401	bool needs_rtnl = setsockopt_needs_rtnl(optname);
 402
 403	if (sockptr_is_null(optval))
 404		val = 0;
 405	else {
 406		if (optlen >= sizeof(int)) {
 407			if (copy_from_sockptr(&val, optval, sizeof(val)))
 408				return -EFAULT;
 409		} else
 410			val = 0;
 411	}
 412
 413	valbool = (val != 0);
 414
 415	if (ip6_mroute_opt(optname))
 416		return ip6_mroute_setsockopt(sk, optname, optval, optlen);
 417
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 418	if (needs_rtnl)
 419		rtnl_lock();
 420	sockopt_lock_sock(sk);
 421
 422	/* Another thread has converted the socket into IPv4 with
 423	 * IPV6_ADDRFORM concurrently.
 424	 */
 425	if (unlikely(sk->sk_family != AF_INET6))
 426		goto unlock;
 427
 428	switch (optname) {
 429
 430	case IPV6_ADDRFORM:
 431		if (optlen < sizeof(int))
 432			goto e_inval;
 433		if (val == PF_INET) {
 434			if (sk->sk_type == SOCK_RAW)
 435				break;
 436
 437			if (sk->sk_protocol == IPPROTO_UDP ||
 438			    sk->sk_protocol == IPPROTO_UDPLITE) {
 439				struct udp_sock *up = udp_sk(sk);
 440				if (up->pending == AF_INET6) {
 441					retv = -EBUSY;
 442					break;
 443				}
 444			} else if (sk->sk_protocol == IPPROTO_TCP) {
 445				if (sk->sk_prot != &tcpv6_prot) {
 446					retv = -EBUSY;
 447					break;
 448				}
 449			} else {
 450				break;
 451			}
 452
 453			if (sk->sk_state != TCP_ESTABLISHED) {
 454				retv = -ENOTCONN;
 455				break;
 456			}
 457
 458			if (ipv6_only_sock(sk) ||
 459			    !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) {
 460				retv = -EADDRNOTAVAIL;
 461				break;
 462			}
 463
 464			__ipv6_sock_mc_close(sk);
 465			__ipv6_sock_ac_close(sk);
 466
 467			/*
 468			 * Sock is moving from IPv6 to IPv4 (sk_prot), so
 469			 * remove it from the refcnt debug socks count in the
 470			 * original family...
 471			 */
 472			sk_refcnt_debug_dec(sk);
 473
 474			if (sk->sk_protocol == IPPROTO_TCP) {
 475				struct inet_connection_sock *icsk = inet_csk(sk);
 476
 477				sock_prot_inuse_add(net, sk->sk_prot, -1);
 478				sock_prot_inuse_add(net, &tcp_prot, 1);
 479
 480				/* Paired with READ_ONCE(sk->sk_prot) in inet6_stream_ops */
 481				WRITE_ONCE(sk->sk_prot, &tcp_prot);
 482				/* Paired with READ_ONCE() in tcp_(get|set)sockopt() */
 483				WRITE_ONCE(icsk->icsk_af_ops, &ipv4_specific);
 484				sk->sk_socket->ops = &inet_stream_ops;
 485				sk->sk_family = PF_INET;
 486				tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
 487			} else {
 488				struct proto *prot = &udp_prot;
 489
 490				if (sk->sk_protocol == IPPROTO_UDPLITE)
 491					prot = &udplite_prot;
 492
 493				sock_prot_inuse_add(net, sk->sk_prot, -1);
 494				sock_prot_inuse_add(net, prot, 1);
 495
 496				/* Paired with READ_ONCE(sk->sk_prot) in inet6_dgram_ops */
 497				WRITE_ONCE(sk->sk_prot, prot);
 498				sk->sk_socket->ops = &inet_dgram_ops;
 499				sk->sk_family = PF_INET;
 500			}
 501
 502			/* Disable all options not to allocate memory anymore,
 503			 * but there is still a race.  See the lockless path
 504			 * in udpv6_sendmsg() and ipv6_local_rxpmtu().
 505			 */
 506			np->rxopt.all = 0;
 507
 508			inet6_cleanup_sock(sk);
 509
 510			/*
 511			 * ... and add it to the refcnt debug socks count
 512			 * in the new family. -acme
 513			 */
 514			sk_refcnt_debug_inc(sk);
 515			module_put(THIS_MODULE);
 516			retv = 0;
 517			break;
 518		}
 519		goto e_inval;
 520
 521	case IPV6_V6ONLY:
 522		if (optlen < sizeof(int) ||
 523		    inet_sk(sk)->inet_num)
 524			goto e_inval;
 525		sk->sk_ipv6only = valbool;
 526		retv = 0;
 527		break;
 528
 529	case IPV6_RECVPKTINFO:
 530		if (optlen < sizeof(int))
 531			goto e_inval;
 532		np->rxopt.bits.rxinfo = valbool;
 533		retv = 0;
 534		break;
 535
 536	case IPV6_2292PKTINFO:
 537		if (optlen < sizeof(int))
 538			goto e_inval;
 539		np->rxopt.bits.rxoinfo = valbool;
 540		retv = 0;
 541		break;
 542
 543	case IPV6_RECVHOPLIMIT:
 544		if (optlen < sizeof(int))
 545			goto e_inval;
 546		np->rxopt.bits.rxhlim = valbool;
 547		retv = 0;
 548		break;
 549
 550	case IPV6_2292HOPLIMIT:
 551		if (optlen < sizeof(int))
 552			goto e_inval;
 553		np->rxopt.bits.rxohlim = valbool;
 554		retv = 0;
 555		break;
 556
 557	case IPV6_RECVRTHDR:
 558		if (optlen < sizeof(int))
 559			goto e_inval;
 560		np->rxopt.bits.srcrt = valbool;
 561		retv = 0;
 562		break;
 563
 564	case IPV6_2292RTHDR:
 565		if (optlen < sizeof(int))
 566			goto e_inval;
 567		np->rxopt.bits.osrcrt = valbool;
 568		retv = 0;
 569		break;
 570
 571	case IPV6_RECVHOPOPTS:
 572		if (optlen < sizeof(int))
 573			goto e_inval;
 574		np->rxopt.bits.hopopts = valbool;
 575		retv = 0;
 576		break;
 577
 578	case IPV6_2292HOPOPTS:
 579		if (optlen < sizeof(int))
 580			goto e_inval;
 581		np->rxopt.bits.ohopopts = valbool;
 582		retv = 0;
 583		break;
 584
 585	case IPV6_RECVDSTOPTS:
 586		if (optlen < sizeof(int))
 587			goto e_inval;
 588		np->rxopt.bits.dstopts = valbool;
 589		retv = 0;
 590		break;
 591
 592	case IPV6_2292DSTOPTS:
 593		if (optlen < sizeof(int))
 594			goto e_inval;
 595		np->rxopt.bits.odstopts = valbool;
 596		retv = 0;
 597		break;
 598
 599	case IPV6_TCLASS:
 600		if (optlen < sizeof(int))
 601			goto e_inval;
 602		if (val < -1 || val > 0xff)
 603			goto e_inval;
 604		/* RFC 3542, 6.5: default traffic class of 0x0 */
 605		if (val == -1)
 606			val = 0;
 607		if (sk->sk_type == SOCK_STREAM) {
 608			val &= ~INET_ECN_MASK;
 609			val |= np->tclass & INET_ECN_MASK;
 610		}
 611		if (np->tclass != val) {
 612			np->tclass = val;
 613			sk_dst_reset(sk);
 614		}
 615		retv = 0;
 616		break;
 617
 618	case IPV6_RECVTCLASS:
 619		if (optlen < sizeof(int))
 620			goto e_inval;
 621		np->rxopt.bits.rxtclass = valbool;
 622		retv = 0;
 623		break;
 624
 625	case IPV6_FLOWINFO:
 626		if (optlen < sizeof(int))
 627			goto e_inval;
 628		np->rxopt.bits.rxflow = valbool;
 629		retv = 0;
 630		break;
 631
 632	case IPV6_RECVPATHMTU:
 633		if (optlen < sizeof(int))
 634			goto e_inval;
 635		np->rxopt.bits.rxpmtu = valbool;
 636		retv = 0;
 637		break;
 638
 639	case IPV6_TRANSPARENT:
 640		if (valbool && !sockopt_ns_capable(net->user_ns, CAP_NET_RAW) &&
 641		    !sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN)) {
 642			retv = -EPERM;
 643			break;
 644		}
 645		if (optlen < sizeof(int))
 646			goto e_inval;
 647		/* we don't have a separate transparent bit for IPV6 we use the one in the IPv4 socket */
 648		inet_sk(sk)->transparent = valbool;
 649		retv = 0;
 650		break;
 651
 652	case IPV6_FREEBIND:
 653		if (optlen < sizeof(int))
 654			goto e_inval;
 655		/* we also don't have a separate freebind bit for IPV6 */
 656		inet_sk(sk)->freebind = valbool;
 657		retv = 0;
 658		break;
 659
 660	case IPV6_RECVORIGDSTADDR:
 661		if (optlen < sizeof(int))
 662			goto e_inval;
 663		np->rxopt.bits.rxorigdstaddr = valbool;
 664		retv = 0;
 665		break;
 666
 667	case IPV6_HOPOPTS:
 668	case IPV6_RTHDRDSTOPTS:
 669	case IPV6_RTHDR:
 670	case IPV6_DSTOPTS:
 671		retv = ipv6_set_opt_hdr(sk, optname, optval, optlen);
 672		break;
 673
 674	case IPV6_PKTINFO:
 675	{
 676		struct in6_pktinfo pkt;
 677
 678		if (optlen == 0)
 679			goto e_inval;
 680		else if (optlen < sizeof(struct in6_pktinfo) ||
 681			 sockptr_is_null(optval))
 682			goto e_inval;
 683
 684		if (copy_from_sockptr(&pkt, optval, sizeof(pkt))) {
 685			retv = -EFAULT;
 686			break;
 687		}
 688		if (!sk_dev_equal_l3scope(sk, pkt.ipi6_ifindex))
 689			goto e_inval;
 690
 691		np->sticky_pktinfo.ipi6_ifindex = pkt.ipi6_ifindex;
 692		np->sticky_pktinfo.ipi6_addr = pkt.ipi6_addr;
 693		retv = 0;
 694		break;
 695	}
 696
 697	case IPV6_2292PKTOPTIONS:
 698	{
 699		struct ipv6_txoptions *opt = NULL;
 700		struct msghdr msg;
 701		struct flowi6 fl6;
 702		struct ipcm6_cookie ipc6;
 703
 704		memset(&fl6, 0, sizeof(fl6));
 705		fl6.flowi6_oif = sk->sk_bound_dev_if;
 706		fl6.flowi6_mark = sk->sk_mark;
 707
 708		if (optlen == 0)
 709			goto update;
 710
 711		/* 1K is probably excessive
 712		 * 1K is surely not enough, 2K per standard header is 16K.
 713		 */
 714		retv = -EINVAL;
 715		if (optlen > 64*1024)
 716			break;
 717
 718		opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL);
 719		retv = -ENOBUFS;
 720		if (!opt)
 721			break;
 722
 723		memset(opt, 0, sizeof(*opt));
 724		refcount_set(&opt->refcnt, 1);
 725		opt->tot_len = sizeof(*opt) + optlen;
 726		retv = -EFAULT;
 727		if (copy_from_sockptr(opt + 1, optval, optlen))
 728			goto done;
 729
 730		msg.msg_controllen = optlen;
 
 731		msg.msg_control = (void *)(opt+1);
 732		ipc6.opt = opt;
 733
 734		retv = ip6_datagram_send_ctl(net, sk, &msg, &fl6, &ipc6);
 735		if (retv)
 736			goto done;
 737update:
 738		retv = 0;
 739		opt = ipv6_update_options(sk, opt);
 740done:
 741		if (opt) {
 742			atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 743			txopt_put(opt);
 744		}
 745		break;
 746	}
 747	case IPV6_UNICAST_HOPS:
 748		if (optlen < sizeof(int))
 749			goto e_inval;
 750		if (val > 255 || val < -1)
 751			goto e_inval;
 752		np->hop_limit = val;
 753		retv = 0;
 754		break;
 755
 756	case IPV6_MULTICAST_HOPS:
 757		if (sk->sk_type == SOCK_STREAM)
 758			break;
 759		if (optlen < sizeof(int))
 760			goto e_inval;
 761		if (val > 255 || val < -1)
 762			goto e_inval;
 763		np->mcast_hops = (val == -1 ? IPV6_DEFAULT_MCASTHOPS : val);
 764		retv = 0;
 765		break;
 766
 767	case IPV6_MULTICAST_LOOP:
 768		if (optlen < sizeof(int))
 769			goto e_inval;
 770		if (val != valbool)
 771			goto e_inval;
 772		np->mc_loop = valbool;
 773		retv = 0;
 774		break;
 775
 776	case IPV6_UNICAST_IF:
 777	{
 778		struct net_device *dev = NULL;
 779		int ifindex;
 780
 781		if (optlen != sizeof(int))
 782			goto e_inval;
 783
 784		ifindex = (__force int)ntohl((__force __be32)val);
 785		if (ifindex == 0) {
 786			np->ucast_oif = 0;
 787			retv = 0;
 788			break;
 789		}
 790
 791		dev = dev_get_by_index(net, ifindex);
 792		retv = -EADDRNOTAVAIL;
 793		if (!dev)
 794			break;
 795		dev_put(dev);
 796
 797		retv = -EINVAL;
 798		if (sk->sk_bound_dev_if)
 799			break;
 800
 801		np->ucast_oif = ifindex;
 802		retv = 0;
 803		break;
 804	}
 805
 806	case IPV6_MULTICAST_IF:
 807		if (sk->sk_type == SOCK_STREAM)
 808			break;
 809		if (optlen < sizeof(int))
 810			goto e_inval;
 811
 812		if (val) {
 813			struct net_device *dev;
 814			int midx;
 815
 816			rcu_read_lock();
 817
 818			dev = dev_get_by_index_rcu(net, val);
 819			if (!dev) {
 820				rcu_read_unlock();
 821				retv = -ENODEV;
 822				break;
 823			}
 824			midx = l3mdev_master_ifindex_rcu(dev);
 825
 826			rcu_read_unlock();
 827
 828			if (sk->sk_bound_dev_if &&
 829			    sk->sk_bound_dev_if != val &&
 830			    (!midx || midx != sk->sk_bound_dev_if))
 831				goto e_inval;
 832		}
 833		np->mcast_oif = val;
 834		retv = 0;
 835		break;
 836	case IPV6_ADD_MEMBERSHIP:
 837	case IPV6_DROP_MEMBERSHIP:
 838	{
 839		struct ipv6_mreq mreq;
 840
 841		if (optlen < sizeof(struct ipv6_mreq))
 842			goto e_inval;
 843
 844		retv = -EPROTO;
 845		if (inet_sk(sk)->is_icsk)
 846			break;
 847
 848		retv = -EFAULT;
 849		if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 850			break;
 851
 852		if (optname == IPV6_ADD_MEMBERSHIP)
 853			retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 854		else
 855			retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 856		break;
 857	}
 858	case IPV6_JOIN_ANYCAST:
 859	case IPV6_LEAVE_ANYCAST:
 860	{
 861		struct ipv6_mreq mreq;
 862
 863		if (optlen < sizeof(struct ipv6_mreq))
 864			goto e_inval;
 865
 866		retv = -EFAULT;
 867		if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 868			break;
 869
 870		if (optname == IPV6_JOIN_ANYCAST)
 871			retv = ipv6_sock_ac_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 872		else
 873			retv = ipv6_sock_ac_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 874		break;
 875	}
 876	case IPV6_MULTICAST_ALL:
 877		if (optlen < sizeof(int))
 878			goto e_inval;
 879		np->mc_all = valbool;
 880		retv = 0;
 881		break;
 882
 883	case MCAST_JOIN_GROUP:
 884	case MCAST_LEAVE_GROUP:
 885		if (in_compat_syscall())
 886			retv = compat_ipv6_mcast_join_leave(sk, optname, optval,
 887							    optlen);
 888		else
 889			retv = ipv6_mcast_join_leave(sk, optname, optval,
 890						     optlen);
 891		break;
 892	case MCAST_JOIN_SOURCE_GROUP:
 893	case MCAST_LEAVE_SOURCE_GROUP:
 894	case MCAST_BLOCK_SOURCE:
 895	case MCAST_UNBLOCK_SOURCE:
 896		retv = do_ipv6_mcast_group_source(sk, optname, optval, optlen);
 897		break;
 898	case MCAST_MSFILTER:
 899		if (in_compat_syscall())
 900			retv = compat_ipv6_set_mcast_msfilter(sk, optval,
 901							      optlen);
 902		else
 903			retv = ipv6_set_mcast_msfilter(sk, optval, optlen);
 904		break;
 905	case IPV6_ROUTER_ALERT:
 906		if (optlen < sizeof(int))
 907			goto e_inval;
 908		retv = ip6_ra_control(sk, val);
 909		break;
 910	case IPV6_ROUTER_ALERT_ISOLATE:
 911		if (optlen < sizeof(int))
 912			goto e_inval;
 913		np->rtalert_isolate = valbool;
 914		retv = 0;
 915		break;
 916	case IPV6_MTU_DISCOVER:
 917		if (optlen < sizeof(int))
 918			goto e_inval;
 919		if (val < IPV6_PMTUDISC_DONT || val > IPV6_PMTUDISC_OMIT)
 920			goto e_inval;
 921		np->pmtudisc = val;
 922		retv = 0;
 923		break;
 924	case IPV6_MTU:
 925		if (optlen < sizeof(int))
 926			goto e_inval;
 927		if (val && val < IPV6_MIN_MTU)
 928			goto e_inval;
 929		np->frag_size = val;
 930		retv = 0;
 931		break;
 932	case IPV6_RECVERR:
 933		if (optlen < sizeof(int))
 934			goto e_inval;
 935		np->recverr = valbool;
 936		if (!val)
 937			skb_queue_purge(&sk->sk_error_queue);
 938		retv = 0;
 939		break;
 940	case IPV6_FLOWINFO_SEND:
 941		if (optlen < sizeof(int))
 942			goto e_inval;
 943		np->sndflow = valbool;
 944		retv = 0;
 945		break;
 946	case IPV6_FLOWLABEL_MGR:
 947		retv = ipv6_flowlabel_opt(sk, optval, optlen);
 948		break;
 949	case IPV6_IPSEC_POLICY:
 950	case IPV6_XFRM_POLICY:
 951		retv = -EPERM;
 952		if (!sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN))
 953			break;
 954		retv = xfrm_user_policy(sk, optname, optval, optlen);
 955		break;
 956
 957	case IPV6_ADDR_PREFERENCES:
 958		if (optlen < sizeof(int))
 959			goto e_inval;
 960		retv = __ip6_sock_set_addr_preferences(sk, val);
 961		break;
 962	case IPV6_MINHOPCOUNT:
 963		if (optlen < sizeof(int))
 964			goto e_inval;
 965		if (val < 0 || val > 255)
 966			goto e_inval;
 967
 968		if (val)
 969			static_branch_enable(&ip6_min_hopcount);
 970
 971		/* tcp_v6_err() and tcp_v6_rcv() might read min_hopcount
 972		 * while we are changing it.
 973		 */
 974		WRITE_ONCE(np->min_hopcount, val);
 975		retv = 0;
 976		break;
 977	case IPV6_DONTFRAG:
 978		np->dontfrag = valbool;
 979		retv = 0;
 980		break;
 981	case IPV6_AUTOFLOWLABEL:
 982		np->autoflowlabel = valbool;
 983		np->autoflowlabel_set = 1;
 984		retv = 0;
 985		break;
 986	case IPV6_RECVFRAGSIZE:
 987		np->rxopt.bits.recvfragsize = valbool;
 988		retv = 0;
 989		break;
 990	case IPV6_RECVERR_RFC4884:
 991		if (optlen < sizeof(int))
 992			goto e_inval;
 993		if (val < 0 || val > 1)
 994			goto e_inval;
 995		np->recverr_rfc4884 = valbool;
 996		retv = 0;
 997		break;
 998	}
 999
1000unlock:
1001	sockopt_release_sock(sk);
1002	if (needs_rtnl)
1003		rtnl_unlock();
1004
1005	return retv;
1006
1007e_inval:
1008	retv = -EINVAL;
1009	goto unlock;
1010}
1011
1012int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1013		    unsigned int optlen)
1014{
1015	int err;
1016
1017	if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1018		return udp_prot.setsockopt(sk, level, optname, optval, optlen);
1019
1020	if (level != SOL_IPV6)
1021		return -ENOPROTOOPT;
1022
1023	err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);
1024#ifdef CONFIG_NETFILTER
1025	/* we need to exclude all possible ENOPROTOOPTs except default case */
1026	if (err == -ENOPROTOOPT && optname != IPV6_IPSEC_POLICY &&
1027			optname != IPV6_XFRM_POLICY)
1028		err = nf_setsockopt(sk, PF_INET6, optname, optval, optlen);
1029#endif
1030	return err;
1031}
1032EXPORT_SYMBOL(ipv6_setsockopt);
1033
1034static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
1035				  int optname, sockptr_t optval, int len)
1036{
1037	struct ipv6_opt_hdr *hdr;
1038
1039	if (!opt)
1040		return 0;
1041
1042	switch (optname) {
1043	case IPV6_HOPOPTS:
1044		hdr = opt->hopopt;
1045		break;
1046	case IPV6_RTHDRDSTOPTS:
1047		hdr = opt->dst0opt;
1048		break;
1049	case IPV6_RTHDR:
1050		hdr = (struct ipv6_opt_hdr *)opt->srcrt;
1051		break;
1052	case IPV6_DSTOPTS:
1053		hdr = opt->dst1opt;
1054		break;
1055	default:
1056		return -EINVAL;	/* should not happen */
1057	}
1058
1059	if (!hdr)
1060		return 0;
1061
1062	len = min_t(unsigned int, len, ipv6_optlen(hdr));
1063	if (copy_to_sockptr(optval, hdr, len))
1064		return -EFAULT;
1065	return len;
1066}
1067
1068static int ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
1069			     sockptr_t optlen, int len)
1070{
1071	const int size0 = offsetof(struct group_filter, gf_slist_flex);
1072	struct group_filter gsf;
1073	int num;
1074	int err;
1075
1076	if (len < size0)
1077		return -EINVAL;
1078	if (copy_from_sockptr(&gsf, optval, size0))
1079		return -EFAULT;
1080	if (gsf.gf_group.ss_family != AF_INET6)
1081		return -EADDRNOTAVAIL;
1082	num = gsf.gf_numsrc;
1083	sockopt_lock_sock(sk);
1084	err = ip6_mc_msfget(sk, &gsf, optval, size0);
1085	if (!err) {
1086		if (num > gsf.gf_numsrc)
1087			num = gsf.gf_numsrc;
1088		len = GROUP_FILTER_SIZE(num);
1089		if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
1090		    copy_to_sockptr(optval, &gsf, size0))
1091			err = -EFAULT;
1092	}
1093	sockopt_release_sock(sk);
1094	return err;
1095}
1096
1097static int compat_ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
1098				    sockptr_t optlen, int len)
1099{
1100	const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
1101	struct compat_group_filter gf32;
1102	struct group_filter gf;
1103	int err;
1104	int num;
1105
1106	if (len < size0)
1107		return -EINVAL;
1108
1109	if (copy_from_sockptr(&gf32, optval, size0))
1110		return -EFAULT;
1111	gf.gf_interface = gf32.gf_interface;
1112	gf.gf_fmode = gf32.gf_fmode;
1113	num = gf.gf_numsrc = gf32.gf_numsrc;
1114	gf.gf_group = gf32.gf_group;
1115
1116	if (gf.gf_group.ss_family != AF_INET6)
1117		return -EADDRNOTAVAIL;
1118
1119	sockopt_lock_sock(sk);
1120	err = ip6_mc_msfget(sk, &gf, optval, size0);
1121	sockopt_release_sock(sk);
1122	if (err)
1123		return err;
1124	if (num > gf.gf_numsrc)
1125		num = gf.gf_numsrc;
1126	len = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32));
1127	if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
1128	    copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_fmode),
1129				   &gf.gf_fmode, sizeof(gf32.gf_fmode)) ||
1130	    copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_numsrc),
1131				   &gf.gf_numsrc, sizeof(gf32.gf_numsrc)))
1132		return -EFAULT;
1133	return 0;
1134}
1135
1136int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
1137		       sockptr_t optval, sockptr_t optlen)
1138{
1139	struct ipv6_pinfo *np = inet6_sk(sk);
1140	int len;
1141	int val;
1142
1143	if (ip6_mroute_opt(optname))
1144		return ip6_mroute_getsockopt(sk, optname, optval, optlen);
1145
1146	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1147		return -EFAULT;
1148	switch (optname) {
1149	case IPV6_ADDRFORM:
1150		if (sk->sk_protocol != IPPROTO_UDP &&
1151		    sk->sk_protocol != IPPROTO_UDPLITE &&
1152		    sk->sk_protocol != IPPROTO_TCP)
1153			return -ENOPROTOOPT;
1154		if (sk->sk_state != TCP_ESTABLISHED)
1155			return -ENOTCONN;
1156		val = sk->sk_family;
1157		break;
1158	case MCAST_MSFILTER:
1159		if (in_compat_syscall())
1160			return compat_ipv6_get_msfilter(sk, optval, optlen, len);
1161		return ipv6_get_msfilter(sk, optval, optlen, len);
1162	case IPV6_2292PKTOPTIONS:
1163	{
1164		struct msghdr msg;
1165		struct sk_buff *skb;
1166
1167		if (sk->sk_type != SOCK_STREAM)
1168			return -ENOPROTOOPT;
1169
1170		if (optval.is_kernel) {
1171			msg.msg_control_is_user = false;
1172			msg.msg_control = optval.kernel;
1173		} else {
1174			msg.msg_control_is_user = true;
1175			msg.msg_control_user = optval.user;
1176		}
1177		msg.msg_controllen = len;
1178		msg.msg_flags = 0;
1179
1180		sockopt_lock_sock(sk);
1181		skb = np->pktoptions;
1182		if (skb)
1183			ip6_datagram_recv_ctl(sk, &msg, skb);
1184		sockopt_release_sock(sk);
1185		if (!skb) {
1186			if (np->rxopt.bits.rxinfo) {
 
1187				struct in6_pktinfo src_info;
1188				src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
 
1189					np->sticky_pktinfo.ipi6_ifindex;
1190				src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr : np->sticky_pktinfo.ipi6_addr;
1191				put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
1192			}
1193			if (np->rxopt.bits.rxhlim) {
1194				int hlim = np->mcast_hops;
 
1195				put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
1196			}
1197			if (np->rxopt.bits.rxtclass) {
1198				int tclass = (int)ip6_tclass(np->rcv_flowinfo);
1199
1200				put_cmsg(&msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
1201			}
1202			if (np->rxopt.bits.rxoinfo) {
 
1203				struct in6_pktinfo src_info;
1204				src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
 
1205					np->sticky_pktinfo.ipi6_ifindex;
1206				src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr :
1207								     np->sticky_pktinfo.ipi6_addr;
1208				put_cmsg(&msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
1209			}
1210			if (np->rxopt.bits.rxohlim) {
1211				int hlim = np->mcast_hops;
 
1212				put_cmsg(&msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
1213			}
1214			if (np->rxopt.bits.rxflow) {
1215				__be32 flowinfo = np->rcv_flowinfo;
1216
1217				put_cmsg(&msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
1218			}
1219		}
1220		len -= msg.msg_controllen;
1221		return copy_to_sockptr(optlen, &len, sizeof(int));
1222	}
1223	case IPV6_MTU:
1224	{
1225		struct dst_entry *dst;
1226
1227		val = 0;
1228		rcu_read_lock();
1229		dst = __sk_dst_get(sk);
1230		if (dst)
1231			val = dst_mtu(dst);
1232		rcu_read_unlock();
1233		if (!val)
1234			return -ENOTCONN;
1235		break;
1236	}
1237
1238	case IPV6_V6ONLY:
1239		val = sk->sk_ipv6only;
1240		break;
1241
1242	case IPV6_RECVPKTINFO:
1243		val = np->rxopt.bits.rxinfo;
1244		break;
1245
1246	case IPV6_2292PKTINFO:
1247		val = np->rxopt.bits.rxoinfo;
1248		break;
1249
1250	case IPV6_RECVHOPLIMIT:
1251		val = np->rxopt.bits.rxhlim;
1252		break;
1253
1254	case IPV6_2292HOPLIMIT:
1255		val = np->rxopt.bits.rxohlim;
1256		break;
1257
1258	case IPV6_RECVRTHDR:
1259		val = np->rxopt.bits.srcrt;
1260		break;
1261
1262	case IPV6_2292RTHDR:
1263		val = np->rxopt.bits.osrcrt;
1264		break;
1265
1266	case IPV6_HOPOPTS:
1267	case IPV6_RTHDRDSTOPTS:
1268	case IPV6_RTHDR:
1269	case IPV6_DSTOPTS:
1270	{
1271		struct ipv6_txoptions *opt;
1272
1273		sockopt_lock_sock(sk);
1274		opt = rcu_dereference_protected(np->opt,
1275						lockdep_sock_is_held(sk));
1276		len = ipv6_getsockopt_sticky(sk, opt, optname, optval, len);
1277		sockopt_release_sock(sk);
1278		/* check if ipv6_getsockopt_sticky() returns err code */
1279		if (len < 0)
1280			return len;
1281		return copy_to_sockptr(optlen, &len, sizeof(int));
1282	}
1283
1284	case IPV6_RECVHOPOPTS:
1285		val = np->rxopt.bits.hopopts;
1286		break;
1287
1288	case IPV6_2292HOPOPTS:
1289		val = np->rxopt.bits.ohopopts;
1290		break;
1291
1292	case IPV6_RECVDSTOPTS:
1293		val = np->rxopt.bits.dstopts;
1294		break;
1295
1296	case IPV6_2292DSTOPTS:
1297		val = np->rxopt.bits.odstopts;
1298		break;
1299
1300	case IPV6_TCLASS:
1301		val = np->tclass;
1302		break;
1303
1304	case IPV6_RECVTCLASS:
1305		val = np->rxopt.bits.rxtclass;
1306		break;
1307
1308	case IPV6_FLOWINFO:
1309		val = np->rxopt.bits.rxflow;
1310		break;
1311
1312	case IPV6_RECVPATHMTU:
1313		val = np->rxopt.bits.rxpmtu;
1314		break;
1315
1316	case IPV6_PATHMTU:
1317	{
1318		struct dst_entry *dst;
1319		struct ip6_mtuinfo mtuinfo;
1320
1321		if (len < sizeof(mtuinfo))
1322			return -EINVAL;
1323
1324		len = sizeof(mtuinfo);
1325		memset(&mtuinfo, 0, sizeof(mtuinfo));
1326
1327		rcu_read_lock();
1328		dst = __sk_dst_get(sk);
1329		if (dst)
1330			mtuinfo.ip6m_mtu = dst_mtu(dst);
1331		rcu_read_unlock();
1332		if (!mtuinfo.ip6m_mtu)
1333			return -ENOTCONN;
1334
1335		if (copy_to_sockptr(optlen, &len, sizeof(int)))
1336			return -EFAULT;
1337		if (copy_to_sockptr(optval, &mtuinfo, len))
1338			return -EFAULT;
1339
1340		return 0;
1341	}
1342
1343	case IPV6_TRANSPARENT:
1344		val = inet_sk(sk)->transparent;
1345		break;
1346
1347	case IPV6_FREEBIND:
1348		val = inet_sk(sk)->freebind;
1349		break;
1350
1351	case IPV6_RECVORIGDSTADDR:
1352		val = np->rxopt.bits.rxorigdstaddr;
1353		break;
1354
1355	case IPV6_UNICAST_HOPS:
1356	case IPV6_MULTICAST_HOPS:
1357	{
1358		struct dst_entry *dst;
1359
1360		if (optname == IPV6_UNICAST_HOPS)
1361			val = np->hop_limit;
1362		else
1363			val = np->mcast_hops;
1364
1365		if (val < 0) {
1366			rcu_read_lock();
1367			dst = __sk_dst_get(sk);
1368			if (dst)
1369				val = ip6_dst_hoplimit(dst);
1370			rcu_read_unlock();
1371		}
1372
1373		if (val < 0)
1374			val = sock_net(sk)->ipv6.devconf_all->hop_limit;
1375		break;
1376	}
1377
1378	case IPV6_MULTICAST_LOOP:
1379		val = np->mc_loop;
1380		break;
1381
1382	case IPV6_MULTICAST_IF:
1383		val = np->mcast_oif;
1384		break;
1385
1386	case IPV6_MULTICAST_ALL:
1387		val = np->mc_all;
1388		break;
1389
1390	case IPV6_UNICAST_IF:
1391		val = (__force int)htonl((__u32) np->ucast_oif);
1392		break;
1393
1394	case IPV6_MTU_DISCOVER:
1395		val = np->pmtudisc;
1396		break;
1397
1398	case IPV6_RECVERR:
1399		val = np->recverr;
1400		break;
1401
1402	case IPV6_FLOWINFO_SEND:
1403		val = np->sndflow;
1404		break;
1405
1406	case IPV6_FLOWLABEL_MGR:
1407	{
1408		struct in6_flowlabel_req freq;
1409		int flags;
1410
1411		if (len < sizeof(freq))
1412			return -EINVAL;
1413
1414		if (copy_from_sockptr(&freq, optval, sizeof(freq)))
1415			return -EFAULT;
1416
1417		if (freq.flr_action != IPV6_FL_A_GET)
1418			return -EINVAL;
1419
1420		len = sizeof(freq);
1421		flags = freq.flr_flags;
1422
1423		memset(&freq, 0, sizeof(freq));
1424
1425		val = ipv6_flowlabel_opt_get(sk, &freq, flags);
1426		if (val < 0)
1427			return val;
1428
1429		if (copy_to_sockptr(optlen, &len, sizeof(int)))
1430			return -EFAULT;
1431		if (copy_to_sockptr(optval, &freq, len))
1432			return -EFAULT;
1433
1434		return 0;
1435	}
1436
1437	case IPV6_ADDR_PREFERENCES:
 
 
1438		val = 0;
1439
1440		if (np->srcprefs & IPV6_PREFER_SRC_TMP)
1441			val |= IPV6_PREFER_SRC_TMP;
1442		else if (np->srcprefs & IPV6_PREFER_SRC_PUBLIC)
1443			val |= IPV6_PREFER_SRC_PUBLIC;
1444		else {
1445			/* XXX: should we return system default? */
1446			val |= IPV6_PREFER_SRC_PUBTMP_DEFAULT;
1447		}
1448
1449		if (np->srcprefs & IPV6_PREFER_SRC_COA)
1450			val |= IPV6_PREFER_SRC_COA;
1451		else
1452			val |= IPV6_PREFER_SRC_HOME;
1453		break;
1454
1455	case IPV6_MINHOPCOUNT:
1456		val = np->min_hopcount;
1457		break;
1458
1459	case IPV6_DONTFRAG:
1460		val = np->dontfrag;
1461		break;
1462
1463	case IPV6_AUTOFLOWLABEL:
1464		val = ip6_autoflowlabel(sock_net(sk), np);
1465		break;
1466
1467	case IPV6_RECVFRAGSIZE:
1468		val = np->rxopt.bits.recvfragsize;
1469		break;
1470
 
 
 
 
1471	case IPV6_ROUTER_ALERT_ISOLATE:
1472		val = np->rtalert_isolate;
1473		break;
1474
1475	case IPV6_RECVERR_RFC4884:
1476		val = np->recverr_rfc4884;
1477		break;
1478
1479	default:
1480		return -ENOPROTOOPT;
1481	}
1482	len = min_t(unsigned int, sizeof(int), len);
1483	if (copy_to_sockptr(optlen, &len, sizeof(int)))
1484		return -EFAULT;
1485	if (copy_to_sockptr(optval, &val, len))
1486		return -EFAULT;
1487	return 0;
1488}
1489
1490int ipv6_getsockopt(struct sock *sk, int level, int optname,
1491		    char __user *optval, int __user *optlen)
1492{
1493	int err;
1494
1495	if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1496		return udp_prot.getsockopt(sk, level, optname, optval, optlen);
1497
1498	if (level != SOL_IPV6)
1499		return -ENOPROTOOPT;
1500
1501	err = do_ipv6_getsockopt(sk, level, optname,
1502				 USER_SOCKPTR(optval), USER_SOCKPTR(optlen));
1503#ifdef CONFIG_NETFILTER
1504	/* we need to exclude all possible ENOPROTOOPTs except default case */
1505	if (err == -ENOPROTOOPT && optname != IPV6_2292PKTOPTIONS) {
1506		int len;
1507
1508		if (get_user(len, optlen))
1509			return -EFAULT;
1510
1511		err = nf_getsockopt(sk, PF_INET6, optname, optval, &len);
1512		if (err >= 0)
1513			err = put_user(len, optlen);
1514	}
1515#endif
1516	return err;
1517}
1518EXPORT_SYMBOL(ipv6_getsockopt);