net/ipv6/ipv6_sockglue.c

   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
  55 struct ip6_ra_chain *ip6_ra_chain;
  56 DEFINE_RWLOCK(ip6_ra_lock);
  57
  58 DEFINE_STATIC_KEY_FALSE(ip6_min_hopcount);
  59
  60 int 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
 102 struct 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
 121 static 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
 141 static 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
 164 static 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
 205 static 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);
 231 out_free_gsf:
 232         kfree(gsf);
 233         return ret;
 234 }
 235
 236 static 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
 275 out_free_p:
 276         kfree(p);
 277         return ret;
 278 }
 279
 280 static 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
 300 static 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
 320 static 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);
 386 sticky_done:
 387         if (opt) {
 388                 atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 389                 txopt_put(opt);
 390         }
 391         return err;
 392 }
 393
 394 int 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                         if (sk->sk_protocol == IPPROTO_TCP) {
 468                                 struct inet_connection_sock *icsk = inet_csk(sk);
 469
 470                                 sock_prot_inuse_add(net, sk->sk_prot, -1);
 471                                 sock_prot_inuse_add(net, &tcp_prot, 1);
 472
 473                                 /* Paired with READ_ONCE(sk->sk_prot) in inet6_stream_ops */
 474                                 WRITE_ONCE(sk->sk_prot, &tcp_prot);
 475                                 /* Paired with READ_ONCE() in tcp_(get|set)sockopt() */
 476                                 WRITE_ONCE(icsk->icsk_af_ops, &ipv4_specific);
 477                                 sk->sk_socket->ops = &inet_stream_ops;
 478                                 sk->sk_family = PF_INET;
 479                                 tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
 480                         } else {
 481                                 struct proto *prot = &udp_prot;
 482
 483                                 if (sk->sk_protocol == IPPROTO_UDPLITE)
 484                                         prot = &udplite_prot;
 485
 486                                 sock_prot_inuse_add(net, sk->sk_prot, -1);
 487                                 sock_prot_inuse_add(net, prot, 1);
 488
 489                                 /* Paired with READ_ONCE(sk->sk_prot) in inet6_dgram_ops */
 490                                 WRITE_ONCE(sk->sk_prot, prot);
 491                                 sk->sk_socket->ops = &inet_dgram_ops;
 492                                 sk->sk_family = PF_INET;
 493                         }
 494
 495                         /* Disable all options not to allocate memory anymore,
 496                          * but there is still a race.  See the lockless path
 497                          * in udpv6_sendmsg() and ipv6_local_rxpmtu().
 498                          */
 499                         np->rxopt.all = 0;
 500
 501                         inet6_cleanup_sock(sk);
 502
 503                         module_put(THIS_MODULE);
 504                         retv = 0;
 505                         break;
 506                 }
 507                 goto e_inval;
 508
 509         case IPV6_V6ONLY:
 510                 if (optlen < sizeof(int) ||
 511                     inet_sk(sk)->inet_num)
 512                         goto e_inval;
 513                 sk->sk_ipv6only = valbool;
 514                 retv = 0;
 515                 break;
 516
 517         case IPV6_RECVPKTINFO:
 518                 if (optlen < sizeof(int))
 519                         goto e_inval;
 520                 np->rxopt.bits.rxinfo = valbool;
 521                 retv = 0;
 522                 break;
 523
 524         case IPV6_2292PKTINFO:
 525                 if (optlen < sizeof(int))
 526                         goto e_inval;
 527                 np->rxopt.bits.rxoinfo = valbool;
 528                 retv = 0;
 529                 break;
 530
 531         case IPV6_RECVHOPLIMIT:
 532                 if (optlen < sizeof(int))
 533                         goto e_inval;
 534                 np->rxopt.bits.rxhlim = valbool;
 535                 retv = 0;
 536                 break;
 537
 538         case IPV6_2292HOPLIMIT:
 539                 if (optlen < sizeof(int))
 540                         goto e_inval;
 541                 np->rxopt.bits.rxohlim = valbool;
 542                 retv = 0;
 543                 break;
 544
 545         case IPV6_RECVRTHDR:
 546                 if (optlen < sizeof(int))
 547                         goto e_inval;
 548                 np->rxopt.bits.srcrt = valbool;
 549                 retv = 0;
 550                 break;
 551
 552         case IPV6_2292RTHDR:
 553                 if (optlen < sizeof(int))
 554                         goto e_inval;
 555                 np->rxopt.bits.osrcrt = valbool;
 556                 retv = 0;
 557                 break;
 558
 559         case IPV6_RECVHOPOPTS:
 560                 if (optlen < sizeof(int))
 561                         goto e_inval;
 562                 np->rxopt.bits.hopopts = valbool;
 563                 retv = 0;
 564                 break;
 565
 566         case IPV6_2292HOPOPTS:
 567                 if (optlen < sizeof(int))
 568                         goto e_inval;
 569                 np->rxopt.bits.ohopopts = valbool;
 570                 retv = 0;
 571                 break;
 572
 573         case IPV6_RECVDSTOPTS:
 574                 if (optlen < sizeof(int))
 575                         goto e_inval;
 576                 np->rxopt.bits.dstopts = valbool;
 577                 retv = 0;
 578                 break;
 579
 580         case IPV6_2292DSTOPTS:
 581                 if (optlen < sizeof(int))
 582                         goto e_inval;
 583                 np->rxopt.bits.odstopts = valbool;
 584                 retv = 0;
 585                 break;
 586
 587         case IPV6_TCLASS:
 588                 if (optlen < sizeof(int))
 589                         goto e_inval;
 590                 if (val < -1 || val > 0xff)
 591                         goto e_inval;
 592                 /* RFC 3542, 6.5: default traffic class of 0x0 */
 593                 if (val == -1)
 594                         val = 0;
 595                 if (sk->sk_type == SOCK_STREAM) {
 596                         val &= ~INET_ECN_MASK;
 597                         val |= np->tclass & INET_ECN_MASK;
 598                 }
 599                 if (np->tclass != val) {
 600                         np->tclass = val;
 601                         sk_dst_reset(sk);
 602                 }
 603                 retv = 0;
 604                 break;
 605
 606         case IPV6_RECVTCLASS:
 607                 if (optlen < sizeof(int))
 608                         goto e_inval;
 609                 np->rxopt.bits.rxtclass = valbool;
 610                 retv = 0;
 611                 break;
 612
 613         case IPV6_FLOWINFO:
 614                 if (optlen < sizeof(int))
 615                         goto e_inval;
 616                 np->rxopt.bits.rxflow = valbool;
 617                 retv = 0;
 618                 break;
 619
 620         case IPV6_RECVPATHMTU:
 621                 if (optlen < sizeof(int))
 622                         goto e_inval;
 623                 np->rxopt.bits.rxpmtu = valbool;
 624                 retv = 0;
 625                 break;
 626
 627         case IPV6_TRANSPARENT:
 628                 if (valbool && !sockopt_ns_capable(net->user_ns, CAP_NET_RAW) &&
 629                     !sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN)) {
 630                         retv = -EPERM;
 631                         break;
 632                 }
 633                 if (optlen < sizeof(int))
 634                         goto e_inval;
 635                 /* we don't have a separate transparent bit for IPV6 we use the one in the IPv4 socket */
 636                 inet_sk(sk)->transparent = valbool;
 637                 retv = 0;
 638                 break;
 639
 640         case IPV6_FREEBIND:
 641                 if (optlen < sizeof(int))
 642                         goto e_inval;
 643                 /* we also don't have a separate freebind bit for IPV6 */
 644                 inet_sk(sk)->freebind = valbool;
 645                 retv = 0;
 646                 break;
 647
 648         case IPV6_RECVORIGDSTADDR:
 649                 if (optlen < sizeof(int))
 650                         goto e_inval;
 651                 np->rxopt.bits.rxorigdstaddr = valbool;
 652                 retv = 0;
 653                 break;
 654
 655         case IPV6_HOPOPTS:
 656         case IPV6_RTHDRDSTOPTS:
 657         case IPV6_RTHDR:
 658         case IPV6_DSTOPTS:
 659                 retv = ipv6_set_opt_hdr(sk, optname, optval, optlen);
 660                 break;
 661
 662         case IPV6_PKTINFO:
 663         {
 664                 struct in6_pktinfo pkt;
 665
 666                 if (optlen == 0)
 667                         goto e_inval;
 668                 else if (optlen < sizeof(struct in6_pktinfo) ||
 669                          sockptr_is_null(optval))
 670                         goto e_inval;
 671
 672                 if (copy_from_sockptr(&pkt, optval, sizeof(pkt))) {
 673                         retv = -EFAULT;
 674                         break;
 675                 }
 676                 if (!sk_dev_equal_l3scope(sk, pkt.ipi6_ifindex))
 677                         goto e_inval;
 678
 679                 np->sticky_pktinfo.ipi6_ifindex = pkt.ipi6_ifindex;
 680                 np->sticky_pktinfo.ipi6_addr = pkt.ipi6_addr;
 681                 retv = 0;
 682                 break;
 683         }
 684
 685         case IPV6_2292PKTOPTIONS:
 686         {
 687                 struct ipv6_txoptions *opt = NULL;
 688                 struct msghdr msg;
 689                 struct flowi6 fl6;
 690                 struct ipcm6_cookie ipc6;
 691
 692                 memset(&fl6, 0, sizeof(fl6));
 693                 fl6.flowi6_oif = sk->sk_bound_dev_if;
 694                 fl6.flowi6_mark = sk->sk_mark;
 695
 696                 if (optlen == 0)
 697                         goto update;
 698
 699                 /* 1K is probably excessive
 700                  * 1K is surely not enough, 2K per standard header is 16K.
 701                  */
 702                 retv = -EINVAL;
 703                 if (optlen > 64*1024)
 704                         break;
 705
 706                 opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL);
 707                 retv = -ENOBUFS;
 708                 if (!opt)
 709                         break;
 710
 711                 memset(opt, 0, sizeof(*opt));
 712                 refcount_set(&opt->refcnt, 1);
 713                 opt->tot_len = sizeof(*opt) + optlen;
 714                 retv = -EFAULT;
 715                 if (copy_from_sockptr(opt + 1, optval, optlen))
 716                         goto done;
 717
 718                 msg.msg_controllen = optlen;
 719                 msg.msg_control_is_user = false;
 720                 msg.msg_control = (void *)(opt+1);
 721                 ipc6.opt = opt;
 722
 723                 retv = ip6_datagram_send_ctl(net, sk, &msg, &fl6, &ipc6);
 724                 if (retv)
 725                         goto done;
 726 update:
 727                 retv = 0;
 728                 opt = ipv6_update_options(sk, opt);
 729 done:
 730                 if (opt) {
 731                         atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 732                         txopt_put(opt);
 733                 }
 734                 break;
 735         }
 736         case IPV6_UNICAST_HOPS:
 737                 if (optlen < sizeof(int))
 738                         goto e_inval;
 739                 if (val > 255 || val < -1)
 740                         goto e_inval;
 741                 np->hop_limit = val;
 742                 retv = 0;
 743                 break;
 744
 745         case IPV6_MULTICAST_HOPS:
 746                 if (sk->sk_type == SOCK_STREAM)
 747                         break;
 748                 if (optlen < sizeof(int))
 749                         goto e_inval;
 750                 if (val > 255 || val < -1)
 751                         goto e_inval;
 752                 np->mcast_hops = (val == -1 ? IPV6_DEFAULT_MCASTHOPS : val);
 753                 retv = 0;
 754                 break;
 755
 756         case IPV6_MULTICAST_LOOP:
 757                 if (optlen < sizeof(int))
 758                         goto e_inval;
 759                 if (val != valbool)
 760                         goto e_inval;
 761                 np->mc_loop = valbool;
 762                 retv = 0;
 763                 break;
 764
 765         case IPV6_UNICAST_IF:
 766         {
 767                 struct net_device *dev = NULL;
 768                 int ifindex;
 769
 770                 if (optlen != sizeof(int))
 771                         goto e_inval;
 772
 773                 ifindex = (__force int)ntohl((__force __be32)val);
 774                 if (ifindex == 0) {
 775                         np->ucast_oif = 0;
 776                         retv = 0;
 777                         break;
 778                 }
 779
 780                 dev = dev_get_by_index(net, ifindex);
 781                 retv = -EADDRNOTAVAIL;
 782                 if (!dev)
 783                         break;
 784                 dev_put(dev);
 785
 786                 retv = -EINVAL;
 787                 if (sk->sk_bound_dev_if)
 788                         break;
 789
 790                 np->ucast_oif = ifindex;
 791                 retv = 0;
 792                 break;
 793         }
 794
 795         case IPV6_MULTICAST_IF:
 796                 if (sk->sk_type == SOCK_STREAM)
 797                         break;
 798                 if (optlen < sizeof(int))
 799                         goto e_inval;
 800
 801                 if (val) {
 802                         struct net_device *dev;
 803                         int midx;
 804
 805                         rcu_read_lock();
 806
 807                         dev = dev_get_by_index_rcu(net, val);
 808                         if (!dev) {
 809                                 rcu_read_unlock();
 810                                 retv = -ENODEV;
 811                                 break;
 812                         }
 813                         midx = l3mdev_master_ifindex_rcu(dev);
 814
 815                         rcu_read_unlock();
 816
 817                         if (sk->sk_bound_dev_if &&
 818                             sk->sk_bound_dev_if != val &&
 819                             (!midx || midx != sk->sk_bound_dev_if))
 820                                 goto e_inval;
 821                 }
 822                 np->mcast_oif = val;
 823                 retv = 0;
 824                 break;
 825         case IPV6_ADD_MEMBERSHIP:
 826         case IPV6_DROP_MEMBERSHIP:
 827         {
 828                 struct ipv6_mreq mreq;
 829
 830                 if (optlen < sizeof(struct ipv6_mreq))
 831                         goto e_inval;
 832
 833                 retv = -EPROTO;
 834                 if (inet_sk(sk)->is_icsk)
 835                         break;
 836
 837                 retv = -EFAULT;
 838                 if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 839                         break;
 840
 841                 if (optname == IPV6_ADD_MEMBERSHIP)
 842                         retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 843                 else
 844                         retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 845                 break;
 846         }
 847         case IPV6_JOIN_ANYCAST:
 848         case IPV6_LEAVE_ANYCAST:
 849         {
 850                 struct ipv6_mreq mreq;
 851
 852                 if (optlen < sizeof(struct ipv6_mreq))
 853                         goto e_inval;
 854
 855                 retv = -EFAULT;
 856                 if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 857                         break;
 858
 859                 if (optname == IPV6_JOIN_ANYCAST)
 860                         retv = ipv6_sock_ac_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 861                 else
 862                         retv = ipv6_sock_ac_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 863                 break;
 864         }
 865         case IPV6_MULTICAST_ALL:
 866                 if (optlen < sizeof(int))
 867                         goto e_inval;
 868                 np->mc_all = valbool;
 869                 retv = 0;
 870                 break;
 871
 872         case MCAST_JOIN_GROUP:
 873         case MCAST_LEAVE_GROUP:
 874                 if (in_compat_syscall())
 875                         retv = compat_ipv6_mcast_join_leave(sk, optname, optval,
 876                                                             optlen);
 877                 else
 878                         retv = ipv6_mcast_join_leave(sk, optname, optval,
 879                                                      optlen);
 880                 break;
 881         case MCAST_JOIN_SOURCE_GROUP:
 882         case MCAST_LEAVE_SOURCE_GROUP:
 883         case MCAST_BLOCK_SOURCE:
 884         case MCAST_UNBLOCK_SOURCE:
 885                 retv = do_ipv6_mcast_group_source(sk, optname, optval, optlen);
 886                 break;
 887         case MCAST_MSFILTER:
 888                 if (in_compat_syscall())
 889                         retv = compat_ipv6_set_mcast_msfilter(sk, optval,
 890                                                               optlen);
 891                 else
 892                         retv = ipv6_set_mcast_msfilter(sk, optval, optlen);
 893                 break;
 894         case IPV6_ROUTER_ALERT:
 895                 if (optlen < sizeof(int))
 896                         goto e_inval;
 897                 retv = ip6_ra_control(sk, val);
 898                 break;
 899         case IPV6_ROUTER_ALERT_ISOLATE:
 900                 if (optlen < sizeof(int))
 901                         goto e_inval;
 902                 np->rtalert_isolate = valbool;
 903                 retv = 0;
 904                 break;
 905         case IPV6_MTU_DISCOVER:
 906                 if (optlen < sizeof(int))
 907                         goto e_inval;
 908                 if (val < IPV6_PMTUDISC_DONT || val > IPV6_PMTUDISC_OMIT)
 909                         goto e_inval;
 910                 np->pmtudisc = val;
 911                 retv = 0;
 912                 break;
 913         case IPV6_MTU:
 914                 if (optlen < sizeof(int))
 915                         goto e_inval;
 916                 if (val && val < IPV6_MIN_MTU)
 917                         goto e_inval;
 918                 np->frag_size = val;
 919                 retv = 0;
 920                 break;
 921         case IPV6_RECVERR:
 922                 if (optlen < sizeof(int))
 923                         goto e_inval;
 924                 np->recverr = valbool;
 925                 if (!val)
 926                         skb_queue_purge(&sk->sk_error_queue);
 927                 retv = 0;
 928                 break;
 929         case IPV6_FLOWINFO_SEND:
 930                 if (optlen < sizeof(int))
 931                         goto e_inval;
 932                 np->sndflow = valbool;
 933                 retv = 0;
 934                 break;
 935         case IPV6_FLOWLABEL_MGR:
 936                 retv = ipv6_flowlabel_opt(sk, optval, optlen);
 937                 break;
 938         case IPV6_IPSEC_POLICY:
 939         case IPV6_XFRM_POLICY:
 940                 retv = -EPERM;
 941                 if (!sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN))
 942                         break;
 943                 retv = xfrm_user_policy(sk, optname, optval, optlen);
 944                 break;
 945
 946         case IPV6_ADDR_PREFERENCES:
 947                 if (optlen < sizeof(int))
 948                         goto e_inval;
 949                 retv = __ip6_sock_set_addr_preferences(sk, val);
 950                 break;
 951         case IPV6_MINHOPCOUNT:
 952                 if (optlen < sizeof(int))
 953                         goto e_inval;
 954                 if (val < 0 || val > 255)
 955                         goto e_inval;
 956
 957                 if (val)
 958                         static_branch_enable(&ip6_min_hopcount);
 959
 960                 /* tcp_v6_err() and tcp_v6_rcv() might read min_hopcount
 961                  * while we are changing it.
 962                  */
 963                 WRITE_ONCE(np->min_hopcount, val);
 964                 retv = 0;
 965                 break;
 966         case IPV6_DONTFRAG:
 967                 np->dontfrag = valbool;
 968                 retv = 0;
 969                 break;
 970         case IPV6_AUTOFLOWLABEL:
 971                 np->autoflowlabel = valbool;
 972                 np->autoflowlabel_set = 1;
 973                 retv = 0;
 974                 break;
 975         case IPV6_RECVFRAGSIZE:
 976                 np->rxopt.bits.recvfragsize = valbool;
 977                 retv = 0;
 978                 break;
 979         case IPV6_RECVERR_RFC4884:
 980                 if (optlen < sizeof(int))
 981                         goto e_inval;
 982                 if (val < 0 || val > 1)
 983                         goto e_inval;
 984                 np->recverr_rfc4884 = valbool;
 985                 retv = 0;
 986                 break;
 987         }
 988
 989 unlock:
 990         sockopt_release_sock(sk);
 991         if (needs_rtnl)
 992                 rtnl_unlock();
 993
 994         return retv;
 995
 996 e_inval:
 997         retv = -EINVAL;
 998         goto unlock;
 999 }
1000
1001 int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1002                     unsigned int optlen)
1003 {
1004         int err;
1005
1006         if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1007                 return udp_prot.setsockopt(sk, level, optname, optval, optlen);
1008
1009         if (level != SOL_IPV6)
1010                 return -ENOPROTOOPT;
1011
1012         err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);
1013 #ifdef CONFIG_NETFILTER
1014         /* we need to exclude all possible ENOPROTOOPTs except default case */
1015         if (err == -ENOPROTOOPT && optname != IPV6_IPSEC_POLICY &&
1016                         optname != IPV6_XFRM_POLICY)
1017                 err = nf_setsockopt(sk, PF_INET6, optname, optval, optlen);
1018 #endif
1019         return err;
1020 }
1021 EXPORT_SYMBOL(ipv6_setsockopt);
1022
1023 static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
1024                                   int optname, sockptr_t optval, int len)
1025 {
1026         struct ipv6_opt_hdr *hdr;
1027
1028         if (!opt)
1029                 return 0;
1030
1031         switch (optname) {
1032         case IPV6_HOPOPTS:
1033                 hdr = opt->hopopt;
1034                 break;
1035         case IPV6_RTHDRDSTOPTS:
1036                 hdr = opt->dst0opt;
1037                 break;
1038         case IPV6_RTHDR:
1039                 hdr = (struct ipv6_opt_hdr *)opt->srcrt;
1040                 break;
1041         case IPV6_DSTOPTS:
1042                 hdr = opt->dst1opt;
1043                 break;
1044         default:
1045                 return -EINVAL; /* should not happen */
1046         }
1047
1048         if (!hdr)
1049                 return 0;
1050
1051         len = min_t(unsigned int, len, ipv6_optlen(hdr));
1052         if (copy_to_sockptr(optval, hdr, len))
1053                 return -EFAULT;
1054         return len;
1055 }
1056
1057 static int ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
1058                              sockptr_t optlen, int len)
1059 {
1060         const int size0 = offsetof(struct group_filter, gf_slist_flex);
1061         struct group_filter gsf;
1062         int num;
1063         int err;
1064
1065         if (len < size0)
1066                 return -EINVAL;
1067         if (copy_from_sockptr(&gsf, optval, size0))
1068                 return -EFAULT;
1069         if (gsf.gf_group.ss_family != AF_INET6)
1070                 return -EADDRNOTAVAIL;
1071         num = gsf.gf_numsrc;
1072         sockopt_lock_sock(sk);
1073         err = ip6_mc_msfget(sk, &gsf, optval, size0);
1074         if (!err) {
1075                 if (num > gsf.gf_numsrc)
1076                         num = gsf.gf_numsrc;
1077                 len = GROUP_FILTER_SIZE(num);
1078                 if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
1079                     copy_to_sockptr(optval, &gsf, size0))
1080                         err = -EFAULT;
1081         }
1082         sockopt_release_sock(sk);
1083         return err;
1084 }
1085
1086 static int compat_ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
1087                                     sockptr_t optlen, int len)
1088 {
1089         const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
1090         struct compat_group_filter gf32;
1091         struct group_filter gf;
1092         int err;
1093         int num;
1094
1095         if (len < size0)
1096                 return -EINVAL;
1097
1098         if (copy_from_sockptr(&gf32, optval, size0))
1099                 return -EFAULT;
1100         gf.gf_interface = gf32.gf_interface;
1101         gf.gf_fmode = gf32.gf_fmode;
1102         num = gf.gf_numsrc = gf32.gf_numsrc;
1103         gf.gf_group = gf32.gf_group;
1104
1105         if (gf.gf_group.ss_family != AF_INET6)
1106                 return -EADDRNOTAVAIL;
1107
1108         sockopt_lock_sock(sk);
1109         err = ip6_mc_msfget(sk, &gf, optval, size0);
1110         sockopt_release_sock(sk);
1111         if (err)
1112                 return err;
1113         if (num > gf.gf_numsrc)
1114                 num = gf.gf_numsrc;
1115         len = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32));
1116         if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
1117             copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_fmode),
1118                                    &gf.gf_fmode, sizeof(gf32.gf_fmode)) ||
1119             copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_numsrc),
1120                                    &gf.gf_numsrc, sizeof(gf32.gf_numsrc)))
1121                 return -EFAULT;
1122         return 0;
1123 }
1124
1125 int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
1126                        sockptr_t optval, sockptr_t optlen)
1127 {
1128         struct ipv6_pinfo *np = inet6_sk(sk);
1129         int len;
1130         int val;
1131
1132         if (ip6_mroute_opt(optname))
1133                 return ip6_mroute_getsockopt(sk, optname, optval, optlen);
1134
1135         if (copy_from_sockptr(&len, optlen, sizeof(int)))
1136                 return -EFAULT;
1137         switch (optname) {
1138         case IPV6_ADDRFORM:
1139                 if (sk->sk_protocol != IPPROTO_UDP &&
1140                     sk->sk_protocol != IPPROTO_UDPLITE &&
1141                     sk->sk_protocol != IPPROTO_TCP)
1142                         return -ENOPROTOOPT;
1143                 if (sk->sk_state != TCP_ESTABLISHED)
1144                         return -ENOTCONN;
1145                 val = sk->sk_family;
1146                 break;
1147         case MCAST_MSFILTER:
1148                 if (in_compat_syscall())
1149                         return compat_ipv6_get_msfilter(sk, optval, optlen, len);
1150                 return ipv6_get_msfilter(sk, optval, optlen, len);
1151         case IPV6_2292PKTOPTIONS:
1152         {
1153                 struct msghdr msg;
1154                 struct sk_buff *skb;
1155
1156                 if (sk->sk_type != SOCK_STREAM)
1157                         return -ENOPROTOOPT;
1158
1159                 if (optval.is_kernel) {
1160                         msg.msg_control_is_user = false;
1161                         msg.msg_control = optval.kernel;
1162                 } else {
1163                         msg.msg_control_is_user = true;
1164                         msg.msg_control_user = optval.user;
1165                 }
1166                 msg.msg_controllen = len;
1167                 msg.msg_flags = 0;
1168
1169                 sockopt_lock_sock(sk);
1170                 skb = np->pktoptions;
1171                 if (skb)
1172                         ip6_datagram_recv_ctl(sk, &msg, skb);
1173                 sockopt_release_sock(sk);
1174                 if (!skb) {
1175                         if (np->rxopt.bits.rxinfo) {
1176                                 struct in6_pktinfo src_info;
1177                                 src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
1178                                         np->sticky_pktinfo.ipi6_ifindex;
1179                                 src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr : np->sticky_pktinfo.ipi6_addr;
1180                                 put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
1181                         }
1182                         if (np->rxopt.bits.rxhlim) {
1183                                 int hlim = np->mcast_hops;
1184                                 put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
1185                         }
1186                         if (np->rxopt.bits.rxtclass) {
1187                                 int tclass = (int)ip6_tclass(np->rcv_flowinfo);
1188
1189                                 put_cmsg(&msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
1190                         }
1191                         if (np->rxopt.bits.rxoinfo) {
1192                                 struct in6_pktinfo src_info;
1193                                 src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
1194                                         np->sticky_pktinfo.ipi6_ifindex;
1195                                 src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr :
1196                                                                      np->sticky_pktinfo.ipi6_addr;
1197                                 put_cmsg(&msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
1198                         }
1199                         if (np->rxopt.bits.rxohlim) {
1200                                 int hlim = np->mcast_hops;
1201                                 put_cmsg(&msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
1202                         }
1203                         if (np->rxopt.bits.rxflow) {
1204                                 __be32 flowinfo = np->rcv_flowinfo;
1205
1206                                 put_cmsg(&msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
1207                         }
1208                 }
1209                 len -= msg.msg_controllen;
1210                 return copy_to_sockptr(optlen, &len, sizeof(int));
1211         }
1212         case IPV6_MTU:
1213         {
1214                 struct dst_entry *dst;
1215
1216                 val = 0;
1217                 rcu_read_lock();
1218                 dst = __sk_dst_get(sk);
1219                 if (dst)
1220                         val = dst_mtu(dst);
1221                 rcu_read_unlock();
1222                 if (!val)
1223                         return -ENOTCONN;
1224                 break;
1225         }
1226
1227         case IPV6_V6ONLY:
1228                 val = sk->sk_ipv6only;
1229                 break;
1230
1231         case IPV6_RECVPKTINFO:
1232                 val = np->rxopt.bits.rxinfo;
1233                 break;
1234
1235         case IPV6_2292PKTINFO:
1236                 val = np->rxopt.bits.rxoinfo;
1237                 break;
1238
1239         case IPV6_RECVHOPLIMIT:
1240                 val = np->rxopt.bits.rxhlim;
1241                 break;
1242
1243         case IPV6_2292HOPLIMIT:
1244                 val = np->rxopt.bits.rxohlim;
1245                 break;
1246
1247         case IPV6_RECVRTHDR:
1248                 val = np->rxopt.bits.srcrt;
1249                 break;
1250
1251         case IPV6_2292RTHDR:
1252                 val = np->rxopt.bits.osrcrt;
1253                 break;
1254
1255         case IPV6_HOPOPTS:
1256         case IPV6_RTHDRDSTOPTS:
1257         case IPV6_RTHDR:
1258         case IPV6_DSTOPTS:
1259         {
1260                 struct ipv6_txoptions *opt;
1261
1262                 sockopt_lock_sock(sk);
1263                 opt = rcu_dereference_protected(np->opt,
1264                                                 lockdep_sock_is_held(sk));
1265                 len = ipv6_getsockopt_sticky(sk, opt, optname, optval, len);
1266                 sockopt_release_sock(sk);
1267                 /* check if ipv6_getsockopt_sticky() returns err code */
1268                 if (len < 0)
1269                         return len;
1270                 return copy_to_sockptr(optlen, &len, sizeof(int));
1271         }
1272
1273         case IPV6_RECVHOPOPTS:
1274                 val = np->rxopt.bits.hopopts;
1275                 break;
1276
1277         case IPV6_2292HOPOPTS:
1278                 val = np->rxopt.bits.ohopopts;
1279                 break;
1280
1281         case IPV6_RECVDSTOPTS:
1282                 val = np->rxopt.bits.dstopts;
1283                 break;
1284
1285         case IPV6_2292DSTOPTS:
1286                 val = np->rxopt.bits.odstopts;
1287                 break;
1288
1289         case IPV6_TCLASS:
1290                 val = np->tclass;
1291                 break;
1292
1293         case IPV6_RECVTCLASS:
1294                 val = np->rxopt.bits.rxtclass;
1295                 break;
1296
1297         case IPV6_FLOWINFO:
1298                 val = np->rxopt.bits.rxflow;
1299                 break;
1300
1301         case IPV6_RECVPATHMTU:
1302                 val = np->rxopt.bits.rxpmtu;
1303                 break;
1304
1305         case IPV6_PATHMTU:
1306         {
1307                 struct dst_entry *dst;
1308                 struct ip6_mtuinfo mtuinfo;
1309
1310                 if (len < sizeof(mtuinfo))
1311                         return -EINVAL;
1312
1313                 len = sizeof(mtuinfo);
1314                 memset(&mtuinfo, 0, sizeof(mtuinfo));
1315
1316                 rcu_read_lock();
1317                 dst = __sk_dst_get(sk);
1318                 if (dst)
1319                         mtuinfo.ip6m_mtu = dst_mtu(dst);
1320                 rcu_read_unlock();
1321                 if (!mtuinfo.ip6m_mtu)
1322                         return -ENOTCONN;
1323
1324                 if (copy_to_sockptr(optlen, &len, sizeof(int)))
1325                         return -EFAULT;
1326                 if (copy_to_sockptr(optval, &mtuinfo, len))
1327                         return -EFAULT;
1328
1329                 return 0;
1330         }
1331
1332         case IPV6_TRANSPARENT:
1333                 val = inet_sk(sk)->transparent;
1334                 break;
1335
1336         case IPV6_FREEBIND:
1337                 val = inet_sk(sk)->freebind;
1338                 break;
1339
1340         case IPV6_RECVORIGDSTADDR:
1341                 val = np->rxopt.bits.rxorigdstaddr;
1342                 break;
1343
1344         case IPV6_UNICAST_HOPS:
1345         case IPV6_MULTICAST_HOPS:
1346         {
1347                 struct dst_entry *dst;
1348
1349                 if (optname == IPV6_UNICAST_HOPS)
1350                         val = np->hop_limit;
1351                 else
1352                         val = np->mcast_hops;
1353
1354                 if (val < 0) {
1355                         rcu_read_lock();
1356                         dst = __sk_dst_get(sk);
1357                         if (dst)
1358                                 val = ip6_dst_hoplimit(dst);
1359                         rcu_read_unlock();
1360                 }
1361
1362                 if (val < 0)
1363                         val = sock_net(sk)->ipv6.devconf_all->hop_limit;
1364                 break;
1365         }
1366
1367         case IPV6_MULTICAST_LOOP:
1368                 val = np->mc_loop;
1369                 break;
1370
1371         case IPV6_MULTICAST_IF:
1372                 val = np->mcast_oif;
1373                 break;
1374
1375         case IPV6_MULTICAST_ALL:
1376                 val = np->mc_all;
1377                 break;
1378
1379         case IPV6_UNICAST_IF:
1380                 val = (__force int)htonl((__u32) np->ucast_oif);
1381                 break;
1382
1383         case IPV6_MTU_DISCOVER:
1384                 val = np->pmtudisc;
1385                 break;
1386
1387         case IPV6_RECVERR:
1388                 val = np->recverr;
1389                 break;
1390
1391         case IPV6_FLOWINFO_SEND:
1392                 val = np->sndflow;
1393                 break;
1394
1395         case IPV6_FLOWLABEL_MGR:
1396         {
1397                 struct in6_flowlabel_req freq;
1398                 int flags;
1399
1400                 if (len < sizeof(freq))
1401                         return -EINVAL;
1402
1403                 if (copy_from_sockptr(&freq, optval, sizeof(freq)))
1404                         return -EFAULT;
1405
1406                 if (freq.flr_action != IPV6_FL_A_GET)
1407                         return -EINVAL;
1408
1409                 len = sizeof(freq);
1410                 flags = freq.flr_flags;
1411
1412                 memset(&freq, 0, sizeof(freq));
1413
1414                 val = ipv6_flowlabel_opt_get(sk, &freq, flags);
1415                 if (val < 0)
1416                         return val;
1417
1418                 if (copy_to_sockptr(optlen, &len, sizeof(int)))
1419                         return -EFAULT;
1420                 if (copy_to_sockptr(optval, &freq, len))
1421                         return -EFAULT;
1422
1423                 return 0;
1424         }
1425
1426         case IPV6_ADDR_PREFERENCES:
1427                 val = 0;
1428
1429                 if (np->srcprefs & IPV6_PREFER_SRC_TMP)
1430                         val |= IPV6_PREFER_SRC_TMP;
1431                 else if (np->srcprefs & IPV6_PREFER_SRC_PUBLIC)
1432                         val |= IPV6_PREFER_SRC_PUBLIC;
1433                 else {
1434                         /* XXX: should we return system default? */
1435                         val |= IPV6_PREFER_SRC_PUBTMP_DEFAULT;
1436                 }
1437
1438                 if (np->srcprefs & IPV6_PREFER_SRC_COA)
1439                         val |= IPV6_PREFER_SRC_COA;
1440                 else
1441                         val |= IPV6_PREFER_SRC_HOME;
1442                 break;
1443
1444         case IPV6_MINHOPCOUNT:
1445                 val = np->min_hopcount;
1446                 break;
1447
1448         case IPV6_DONTFRAG:
1449                 val = np->dontfrag;
1450                 break;
1451
1452         case IPV6_AUTOFLOWLABEL:
1453                 val = ip6_autoflowlabel(sock_net(sk), np);
1454                 break;
1455
1456         case IPV6_RECVFRAGSIZE:
1457                 val = np->rxopt.bits.recvfragsize;
1458                 break;
1459
1460         case IPV6_ROUTER_ALERT_ISOLATE:
1461                 val = np->rtalert_isolate;
1462                 break;
1463
1464         case IPV6_RECVERR_RFC4884:
1465                 val = np->recverr_rfc4884;
1466                 break;
1467
1468         default:
1469                 return -ENOPROTOOPT;
1470         }
1471         len = min_t(unsigned int, sizeof(int), len);
1472         if (copy_to_sockptr(optlen, &len, sizeof(int)))
1473                 return -EFAULT;
1474         if (copy_to_sockptr(optval, &val, len))
1475                 return -EFAULT;
1476         return 0;
1477 }
1478
1479 int ipv6_getsockopt(struct sock *sk, int level, int optname,
1480                     char __user *optval, int __user *optlen)
1481 {
1482         int err;
1483
1484         if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1485                 return udp_prot.getsockopt(sk, level, optname, optval, optlen);
1486
1487         if (level != SOL_IPV6)
1488                 return -ENOPROTOOPT;
1489
1490         err = do_ipv6_getsockopt(sk, level, optname,
1491                                  USER_SOCKPTR(optval), USER_SOCKPTR(optlen));
1492 #ifdef CONFIG_NETFILTER
1493         /* we need to exclude all possible ENOPROTOOPTs except default case */
1494         if (err == -ENOPROTOOPT && optname != IPV6_2292PKTOPTIONS) {
1495                 int len;
1496
1497                 if (get_user(len, optlen))
1498                         return -EFAULT;
1499
1500                 err = nf_getsockopt(sk, PF_INET6, optname, optval, &len);
1501                 if (err >= 0)
1502                         err = put_user(len, optlen);
1503         }
1504 #endif
1505         return err;
1506 }
1507 EXPORT_SYMBOL(ipv6_getsockopt);