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 int ip6_ra_control(struct sock *sk, int sel)
  59 {
  60         struct ip6_ra_chain *ra, *new_ra, **rap;
  61
  62         /* RA packet may be delivered ONLY to IPPROTO_RAW socket */
  63         if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num != IPPROTO_RAW)
  64                 return -ENOPROTOOPT;
  65
  66         new_ra = (sel >= 0) ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
  67         if (sel >= 0 && !new_ra)
  68                 return -ENOMEM;
  69
  70         write_lock_bh(&ip6_ra_lock);
  71         for (rap = &ip6_ra_chain; (ra = *rap) != NULL; rap = &ra->next) {
  72                 if (ra->sk == sk) {
  73                         if (sel >= 0) {
  74                                 write_unlock_bh(&ip6_ra_lock);
  75                                 kfree(new_ra);
  76                                 return -EADDRINUSE;
  77                         }
  78
  79                         *rap = ra->next;
  80                         write_unlock_bh(&ip6_ra_lock);
  81
  82                         sock_put(sk);
  83                         kfree(ra);
  84                         return 0;
  85                 }
  86         }
  87         if (!new_ra) {
  88                 write_unlock_bh(&ip6_ra_lock);
  89                 return -ENOBUFS;
  90         }
  91         new_ra->sk = sk;
  92         new_ra->sel = sel;
  93         new_ra->next = ra;
  94         *rap = new_ra;
  95         sock_hold(sk);
  96         write_unlock_bh(&ip6_ra_lock);
  97         return 0;
  98 }
  99
 100 struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
 101                                            struct ipv6_txoptions *opt)
 102 {
 103         if (inet_sk(sk)->is_icsk) {
 104                 if (opt &&
 105                     !((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) &&
 106                     inet_sk(sk)->inet_daddr != LOOPBACK4_IPV6) {
 107                         struct inet_connection_sock *icsk = inet_csk(sk);
 108                         icsk->icsk_ext_hdr_len = opt->opt_flen + opt->opt_nflen;
 109                         icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
 110                 }
 111         }
 112         opt = xchg((__force struct ipv6_txoptions **)&inet6_sk(sk)->opt,
 113                    opt);
 114         sk_dst_reset(sk);
 115
 116         return opt;
 117 }
 118
 119 static bool setsockopt_needs_rtnl(int optname)
 120 {
 121         switch (optname) {
 122         case IPV6_ADDRFORM:
 123         case IPV6_ADD_MEMBERSHIP:
 124         case IPV6_DROP_MEMBERSHIP:
 125         case IPV6_JOIN_ANYCAST:
 126         case IPV6_LEAVE_ANYCAST:
 127         case MCAST_JOIN_GROUP:
 128         case MCAST_LEAVE_GROUP:
 129         case MCAST_JOIN_SOURCE_GROUP:
 130         case MCAST_LEAVE_SOURCE_GROUP:
 131         case MCAST_BLOCK_SOURCE:
 132         case MCAST_UNBLOCK_SOURCE:
 133         case MCAST_MSFILTER:
 134                 return true;
 135         }
 136         return false;
 137 }
 138
 139 static int copy_group_source_from_sockptr(struct group_source_req *greqs,
 140                 sockptr_t optval, int optlen)
 141 {
 142         if (in_compat_syscall()) {
 143                 struct compat_group_source_req gr32;
 144
 145                 if (optlen < sizeof(gr32))
 146                         return -EINVAL;
 147                 if (copy_from_sockptr(&gr32, optval, sizeof(gr32)))
 148                         return -EFAULT;
 149                 greqs->gsr_interface = gr32.gsr_interface;
 150                 greqs->gsr_group = gr32.gsr_group;
 151                 greqs->gsr_source = gr32.gsr_source;
 152         } else {
 153                 if (optlen < sizeof(*greqs))
 154                         return -EINVAL;
 155                 if (copy_from_sockptr(greqs, optval, sizeof(*greqs)))
 156                         return -EFAULT;
 157         }
 158
 159         return 0;
 160 }
 161
 162 static int do_ipv6_mcast_group_source(struct sock *sk, int optname,
 163                 sockptr_t optval, int optlen)
 164 {
 165         struct group_source_req greqs;
 166         int omode, add;
 167         int ret;
 168
 169         ret = copy_group_source_from_sockptr(&greqs, optval, optlen);
 170         if (ret)
 171                 return ret;
 172
 173         if (greqs.gsr_group.ss_family != AF_INET6 ||
 174             greqs.gsr_source.ss_family != AF_INET6)
 175                 return -EADDRNOTAVAIL;
 176
 177         if (optname == MCAST_BLOCK_SOURCE) {
 178                 omode = MCAST_EXCLUDE;
 179                 add = 1;
 180         } else if (optname == MCAST_UNBLOCK_SOURCE) {
 181                 omode = MCAST_EXCLUDE;
 182                 add = 0;
 183         } else if (optname == MCAST_JOIN_SOURCE_GROUP) {
 184                 struct sockaddr_in6 *psin6;
 185                 int retv;
 186
 187                 psin6 = (struct sockaddr_in6 *)&greqs.gsr_group;
 188                 retv = ipv6_sock_mc_join_ssm(sk, greqs.gsr_interface,
 189                                              &psin6->sin6_addr,
 190                                              MCAST_INCLUDE);
 191                 /* prior join w/ different source is ok */
 192                 if (retv && retv != -EADDRINUSE)
 193                         return retv;
 194                 omode = MCAST_INCLUDE;
 195                 add = 1;
 196         } else /* MCAST_LEAVE_SOURCE_GROUP */ {
 197                 omode = MCAST_INCLUDE;
 198                 add = 0;
 199         }
 200         return ip6_mc_source(add, omode, sk, &greqs);
 201 }
 202
 203 static int ipv6_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
 204                 int optlen)
 205 {
 206         struct group_filter *gsf;
 207         int ret;
 208
 209         if (optlen < GROUP_FILTER_SIZE(0))
 210                 return -EINVAL;
 211         if (optlen > sysctl_optmem_max)
 212                 return -ENOBUFS;
 213
 214         gsf = memdup_sockptr(optval, optlen);
 215         if (IS_ERR(gsf))
 216                 return PTR_ERR(gsf);
 217
 218         /* numsrc >= (4G-140)/128 overflow in 32 bits */
 219         ret = -ENOBUFS;
 220         if (gsf->gf_numsrc >= 0x1ffffffU ||
 221             gsf->gf_numsrc > sysctl_mld_max_msf)
 222                 goto out_free_gsf;
 223
 224         ret = -EINVAL;
 225         if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen)
 226                 goto out_free_gsf;
 227
 228         ret = ip6_mc_msfilter(sk, gsf, gsf->gf_slist_flex);
 229 out_free_gsf:
 230         kfree(gsf);
 231         return ret;
 232 }
 233
 234 static int compat_ipv6_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
 235                 int optlen)
 236 {
 237         const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
 238         struct compat_group_filter *gf32;
 239         void *p;
 240         int ret;
 241         int n;
 242
 243         if (optlen < size0)
 244                 return -EINVAL;
 245         if (optlen > sysctl_optmem_max - 4)
 246                 return -ENOBUFS;
 247
 248         p = kmalloc(optlen + 4, GFP_KERNEL);
 249         if (!p)
 250                 return -ENOMEM;
 251
 252         gf32 = p + 4; /* we want ->gf_group and ->gf_slist_flex aligned */
 253         ret = -EFAULT;
 254         if (copy_from_sockptr(gf32, optval, optlen))
 255                 goto out_free_p;
 256
 257         /* numsrc >= (4G-140)/128 overflow in 32 bits */
 258         ret = -ENOBUFS;
 259         n = gf32->gf_numsrc;
 260         if (n >= 0x1ffffffU || n > sysctl_mld_max_msf)
 261                 goto out_free_p;
 262
 263         ret = -EINVAL;
 264         if (offsetof(struct compat_group_filter, gf_slist_flex[n]) > optlen)
 265                 goto out_free_p;
 266
 267         ret = ip6_mc_msfilter(sk, &(struct group_filter){
 268                         .gf_interface = gf32->gf_interface,
 269                         .gf_group = gf32->gf_group,
 270                         .gf_fmode = gf32->gf_fmode,
 271                         .gf_numsrc = gf32->gf_numsrc}, gf32->gf_slist_flex);
 272
 273 out_free_p:
 274         kfree(p);
 275         return ret;
 276 }
 277
 278 static int ipv6_mcast_join_leave(struct sock *sk, int optname,
 279                 sockptr_t optval, int optlen)
 280 {
 281         struct sockaddr_in6 *psin6;
 282         struct group_req greq;
 283
 284         if (optlen < sizeof(greq))
 285                 return -EINVAL;
 286         if (copy_from_sockptr(&greq, optval, sizeof(greq)))
 287                 return -EFAULT;
 288
 289         if (greq.gr_group.ss_family != AF_INET6)
 290                 return -EADDRNOTAVAIL;
 291         psin6 = (struct sockaddr_in6 *)&greq.gr_group;
 292         if (optname == MCAST_JOIN_GROUP)
 293                 return ipv6_sock_mc_join(sk, greq.gr_interface,
 294                                          &psin6->sin6_addr);
 295         return ipv6_sock_mc_drop(sk, greq.gr_interface, &psin6->sin6_addr);
 296 }
 297
 298 static int compat_ipv6_mcast_join_leave(struct sock *sk, int optname,
 299                 sockptr_t optval, int optlen)
 300 {
 301         struct compat_group_req gr32;
 302         struct sockaddr_in6 *psin6;
 303
 304         if (optlen < sizeof(gr32))
 305                 return -EINVAL;
 306         if (copy_from_sockptr(&gr32, optval, sizeof(gr32)))
 307                 return -EFAULT;
 308
 309         if (gr32.gr_group.ss_family != AF_INET6)
 310                 return -EADDRNOTAVAIL;
 311         psin6 = (struct sockaddr_in6 *)&gr32.gr_group;
 312         if (optname == MCAST_JOIN_GROUP)
 313                 return ipv6_sock_mc_join(sk, gr32.gr_interface,
 314                                         &psin6->sin6_addr);
 315         return ipv6_sock_mc_drop(sk, gr32.gr_interface, &psin6->sin6_addr);
 316 }
 317
 318 static int ipv6_set_opt_hdr(struct sock *sk, int optname, sockptr_t optval,
 319                 int optlen)
 320 {
 321         struct ipv6_pinfo *np = inet6_sk(sk);
 322         struct ipv6_opt_hdr *new = NULL;
 323         struct net *net = sock_net(sk);
 324         struct ipv6_txoptions *opt;
 325         int err;
 326
 327         /* hop-by-hop / destination options are privileged option */
 328         if (optname != IPV6_RTHDR && !ns_capable(net->user_ns, CAP_NET_RAW))
 329                 return -EPERM;
 330
 331         /* remove any sticky options header with a zero option
 332          * length, per RFC3542.
 333          */
 334         if (optlen > 0) {
 335                 if (sockptr_is_null(optval))
 336                         return -EINVAL;
 337                 if (optlen < sizeof(struct ipv6_opt_hdr) ||
 338                     optlen & 0x7 ||
 339                     optlen > 8 * 255)
 340                         return -EINVAL;
 341
 342                 new = memdup_sockptr(optval, optlen);
 343                 if (IS_ERR(new))
 344                         return PTR_ERR(new);
 345                 if (unlikely(ipv6_optlen(new) > optlen)) {
 346                         kfree(new);
 347                         return -EINVAL;
 348                 }
 349         }
 350
 351         opt = rcu_dereference_protected(np->opt, lockdep_sock_is_held(sk));
 352         opt = ipv6_renew_options(sk, opt, optname, new);
 353         kfree(new);
 354         if (IS_ERR(opt))
 355                 return PTR_ERR(opt);
 356
 357         /* routing header option needs extra check */
 358         err = -EINVAL;
 359         if (optname == IPV6_RTHDR && opt && opt->srcrt) {
 360                 struct ipv6_rt_hdr *rthdr = opt->srcrt;
 361                 switch (rthdr->type) {
 362 #if IS_ENABLED(CONFIG_IPV6_MIP6)
 363                 case IPV6_SRCRT_TYPE_2:
 364                         if (rthdr->hdrlen != 2 || rthdr->segments_left != 1)
 365                                 goto sticky_done;
 366                         break;
 367 #endif
 368                 case IPV6_SRCRT_TYPE_4:
 369                 {
 370                         struct ipv6_sr_hdr *srh =
 371                                 (struct ipv6_sr_hdr *)opt->srcrt;
 372
 373                         if (!seg6_validate_srh(srh, optlen, false))
 374                                 goto sticky_done;
 375                         break;
 376                 }
 377                 default:
 378                         goto sticky_done;
 379                 }
 380         }
 381
 382         err = 0;
 383         opt = ipv6_update_options(sk, opt);
 384 sticky_done:
 385         if (opt) {
 386                 atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 387                 txopt_put(opt);
 388         }
 389         return err;
 390 }
 391
 392 static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
 393                    sockptr_t optval, unsigned int optlen)
 394 {
 395         struct ipv6_pinfo *np = inet6_sk(sk);
 396         struct net *net = sock_net(sk);
 397         int val, valbool;
 398         int retv = -ENOPROTOOPT;
 399         bool needs_rtnl = setsockopt_needs_rtnl(optname);
 400
 401         if (sockptr_is_null(optval))
 402                 val = 0;
 403         else {
 404                 if (optlen >= sizeof(int)) {
 405                         if (copy_from_sockptr(&val, optval, sizeof(val)))
 406                                 return -EFAULT;
 407                 } else
 408                         val = 0;
 409         }
 410
 411         valbool = (val != 0);
 412
 413         if (ip6_mroute_opt(optname))
 414                 return ip6_mroute_setsockopt(sk, optname, optval, optlen);
 415
 416         if (needs_rtnl)
 417                 rtnl_lock();
 418         lock_sock(sk);
 419
 420         switch (optname) {
 421
 422         case IPV6_ADDRFORM:
 423                 if (optlen < sizeof(int))
 424                         goto e_inval;
 425                 if (val == PF_INET) {
 426                         struct ipv6_txoptions *opt;
 427                         struct sk_buff *pktopt;
 428
 429                         if (sk->sk_type == SOCK_RAW)
 430                                 break;
 431
 432                         if (sk->sk_protocol == IPPROTO_UDP ||
 433                             sk->sk_protocol == IPPROTO_UDPLITE) {
 434                                 struct udp_sock *up = udp_sk(sk);
 435                                 if (up->pending == AF_INET6) {
 436                                         retv = -EBUSY;
 437                                         break;
 438                                 }
 439                         } else if (sk->sk_protocol == IPPROTO_TCP) {
 440                                 if (sk->sk_prot != &tcpv6_prot) {
 441                                         retv = -EBUSY;
 442                                         break;
 443                                 }
 444                         } else {
 445                                 break;
 446                         }
 447
 448                         if (sk->sk_state != TCP_ESTABLISHED) {
 449                                 retv = -ENOTCONN;
 450                                 break;
 451                         }
 452
 453                         if (ipv6_only_sock(sk) ||
 454                             !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) {
 455                                 retv = -EADDRNOTAVAIL;
 456                                 break;
 457                         }
 458
 459                         fl6_free_socklist(sk);
 460                         __ipv6_sock_mc_close(sk);
 461                         __ipv6_sock_ac_close(sk);
 462
 463                         /*
 464                          * Sock is moving from IPv6 to IPv4 (sk_prot), so
 465                          * remove it from the refcnt debug socks count in the
 466                          * original family...
 467                          */
 468                         sk_refcnt_debug_dec(sk);
 469
 470                         if (sk->sk_protocol == IPPROTO_TCP) {
 471                                 struct inet_connection_sock *icsk = inet_csk(sk);
 472                                 local_bh_disable();
 473                                 sock_prot_inuse_add(net, sk->sk_prot, -1);
 474                                 sock_prot_inuse_add(net, &tcp_prot, 1);
 475                                 local_bh_enable();
 476                                 sk->sk_prot = &tcp_prot;
 477                                 icsk->icsk_af_ops = &ipv4_specific;
 478                                 sk->sk_socket->ops = &inet_stream_ops;
 479                                 sk->sk_family = PF_INET;
 480                                 tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
 481                         } else {
 482                                 struct proto *prot = &udp_prot;
 483
 484                                 if (sk->sk_protocol == IPPROTO_UDPLITE)
 485                                         prot = &udplite_prot;
 486                                 local_bh_disable();
 487                                 sock_prot_inuse_add(net, sk->sk_prot, -1);
 488                                 sock_prot_inuse_add(net, prot, 1);
 489                                 local_bh_enable();
 490                                 sk->sk_prot = prot;
 491                                 sk->sk_socket->ops = &inet_dgram_ops;
 492                                 sk->sk_family = PF_INET;
 493                         }
 494                         opt = xchg((__force struct ipv6_txoptions **)&np->opt,
 495                                    NULL);
 496                         if (opt) {
 497                                 atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 498                                 txopt_put(opt);
 499                         }
 500                         pktopt = xchg(&np->pktoptions, NULL);
 501                         kfree_skb(pktopt);
 502
 503                         /*
 504                          * ... and add it to the refcnt debug socks count
 505                          * in the new family. -acme
 506                          */
 507                         sk_refcnt_debug_inc(sk);
 508                         module_put(THIS_MODULE);
 509                         retv = 0;
 510                         break;
 511                 }
 512                 goto e_inval;
 513
 514         case IPV6_V6ONLY:
 515                 if (optlen < sizeof(int) ||
 516                     inet_sk(sk)->inet_num)
 517                         goto e_inval;
 518                 sk->sk_ipv6only = valbool;
 519                 retv = 0;
 520                 break;
 521
 522         case IPV6_RECVPKTINFO:
 523                 if (optlen < sizeof(int))
 524                         goto e_inval;
 525                 np->rxopt.bits.rxinfo = valbool;
 526                 retv = 0;
 527                 break;
 528
 529         case IPV6_2292PKTINFO:
 530                 if (optlen < sizeof(int))
 531                         goto e_inval;
 532                 np->rxopt.bits.rxoinfo = valbool;
 533                 retv = 0;
 534                 break;
 535
 536         case IPV6_RECVHOPLIMIT:
 537                 if (optlen < sizeof(int))
 538                         goto e_inval;
 539                 np->rxopt.bits.rxhlim = valbool;
 540                 retv = 0;
 541                 break;
 542
 543         case IPV6_2292HOPLIMIT:
 544                 if (optlen < sizeof(int))
 545                         goto e_inval;
 546                 np->rxopt.bits.rxohlim = valbool;
 547                 retv = 0;
 548                 break;
 549
 550         case IPV6_RECVRTHDR:
 551                 if (optlen < sizeof(int))
 552                         goto e_inval;
 553                 np->rxopt.bits.srcrt = valbool;
 554                 retv = 0;
 555                 break;
 556
 557         case IPV6_2292RTHDR:
 558                 if (optlen < sizeof(int))
 559                         goto e_inval;
 560                 np->rxopt.bits.osrcrt = valbool;
 561                 retv = 0;
 562                 break;
 563
 564         case IPV6_RECVHOPOPTS:
 565                 if (optlen < sizeof(int))
 566                         goto e_inval;
 567                 np->rxopt.bits.hopopts = valbool;
 568                 retv = 0;
 569                 break;
 570
 571         case IPV6_2292HOPOPTS:
 572                 if (optlen < sizeof(int))
 573                         goto e_inval;
 574                 np->rxopt.bits.ohopopts = valbool;
 575                 retv = 0;
 576                 break;
 577
 578         case IPV6_RECVDSTOPTS:
 579                 if (optlen < sizeof(int))
 580                         goto e_inval;
 581                 np->rxopt.bits.dstopts = valbool;
 582                 retv = 0;
 583                 break;
 584
 585         case IPV6_2292DSTOPTS:
 586                 if (optlen < sizeof(int))
 587                         goto e_inval;
 588                 np->rxopt.bits.odstopts = valbool;
 589                 retv = 0;
 590                 break;
 591
 592         case IPV6_TCLASS:
 593                 if (optlen < sizeof(int))
 594                         goto e_inval;
 595                 if (val < -1 || val > 0xff)
 596                         goto e_inval;
 597                 /* RFC 3542, 6.5: default traffic class of 0x0 */
 598                 if (val == -1)
 599                         val = 0;
 600                 np->tclass = val;
 601                 retv = 0;
 602                 break;
 603
 604         case IPV6_RECVTCLASS:
 605                 if (optlen < sizeof(int))
 606                         goto e_inval;
 607                 np->rxopt.bits.rxtclass = valbool;
 608                 retv = 0;
 609                 break;
 610
 611         case IPV6_FLOWINFO:
 612                 if (optlen < sizeof(int))
 613                         goto e_inval;
 614                 np->rxopt.bits.rxflow = valbool;
 615                 retv = 0;
 616                 break;
 617
 618         case IPV6_RECVPATHMTU:
 619                 if (optlen < sizeof(int))
 620                         goto e_inval;
 621                 np->rxopt.bits.rxpmtu = valbool;
 622                 retv = 0;
 623                 break;
 624
 625         case IPV6_TRANSPARENT:
 626                 if (valbool && !ns_capable(net->user_ns, CAP_NET_RAW) &&
 627                     !ns_capable(net->user_ns, CAP_NET_ADMIN)) {
 628                         retv = -EPERM;
 629                         break;
 630                 }
 631                 if (optlen < sizeof(int))
 632                         goto e_inval;
 633                 /* we don't have a separate transparent bit for IPV6 we use the one in the IPv4 socket */
 634                 inet_sk(sk)->transparent = valbool;
 635                 retv = 0;
 636                 break;
 637
 638         case IPV6_FREEBIND:
 639                 if (optlen < sizeof(int))
 640                         goto e_inval;
 641                 /* we also don't have a separate freebind bit for IPV6 */
 642                 inet_sk(sk)->freebind = valbool;
 643                 retv = 0;
 644                 break;
 645
 646         case IPV6_RECVORIGDSTADDR:
 647                 if (optlen < sizeof(int))
 648                         goto e_inval;
 649                 np->rxopt.bits.rxorigdstaddr = valbool;
 650                 retv = 0;
 651                 break;
 652
 653         case IPV6_HOPOPTS:
 654         case IPV6_RTHDRDSTOPTS:
 655         case IPV6_RTHDR:
 656         case IPV6_DSTOPTS:
 657                 retv = ipv6_set_opt_hdr(sk, optname, optval, optlen);
 658                 break;
 659
 660         case IPV6_PKTINFO:
 661         {
 662                 struct in6_pktinfo pkt;
 663
 664                 if (optlen == 0)
 665                         goto e_inval;
 666                 else if (optlen < sizeof(struct in6_pktinfo) ||
 667                          sockptr_is_null(optval))
 668                         goto e_inval;
 669
 670                 if (copy_from_sockptr(&pkt, optval, sizeof(pkt))) {
 671                         retv = -EFAULT;
 672                         break;
 673                 }
 674                 if (!sk_dev_equal_l3scope(sk, pkt.ipi6_ifindex))
 675                         goto e_inval;
 676
 677                 np->sticky_pktinfo.ipi6_ifindex = pkt.ipi6_ifindex;
 678                 np->sticky_pktinfo.ipi6_addr = pkt.ipi6_addr;
 679                 retv = 0;
 680                 break;
 681         }
 682
 683         case IPV6_2292PKTOPTIONS:
 684         {
 685                 struct ipv6_txoptions *opt = NULL;
 686                 struct msghdr msg;
 687                 struct flowi6 fl6;
 688                 struct ipcm6_cookie ipc6;
 689
 690                 memset(&fl6, 0, sizeof(fl6));
 691                 fl6.flowi6_oif = sk->sk_bound_dev_if;
 692                 fl6.flowi6_mark = sk->sk_mark;
 693
 694                 if (optlen == 0)
 695                         goto update;
 696
 697                 /* 1K is probably excessive
 698                  * 1K is surely not enough, 2K per standard header is 16K.
 699                  */
 700                 retv = -EINVAL;
 701                 if (optlen > 64*1024)
 702                         break;
 703
 704                 opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL);
 705                 retv = -ENOBUFS;
 706                 if (!opt)
 707                         break;
 708
 709                 memset(opt, 0, sizeof(*opt));
 710                 refcount_set(&opt->refcnt, 1);
 711                 opt->tot_len = sizeof(*opt) + optlen;
 712                 retv = -EFAULT;
 713                 if (copy_from_sockptr(opt + 1, optval, optlen))
 714                         goto done;
 715
 716                 msg.msg_controllen = optlen;
 717                 msg.msg_control = (void *)(opt+1);
 718                 ipc6.opt = opt;
 719
 720                 retv = ip6_datagram_send_ctl(net, sk, &msg, &fl6, &ipc6);
 721                 if (retv)
 722                         goto done;
 723 update:
 724                 retv = 0;
 725                 opt = ipv6_update_options(sk, opt);
 726 done:
 727                 if (opt) {
 728                         atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 729                         txopt_put(opt);
 730                 }
 731                 break;
 732         }
 733         case IPV6_UNICAST_HOPS:
 734                 if (optlen < sizeof(int))
 735                         goto e_inval;
 736                 if (val > 255 || val < -1)
 737                         goto e_inval;
 738                 np->hop_limit = val;
 739                 retv = 0;
 740                 break;
 741
 742         case IPV6_MULTICAST_HOPS:
 743                 if (sk->sk_type == SOCK_STREAM)
 744                         break;
 745                 if (optlen < sizeof(int))
 746                         goto e_inval;
 747                 if (val > 255 || val < -1)
 748                         goto e_inval;
 749                 np->mcast_hops = (val == -1 ? IPV6_DEFAULT_MCASTHOPS : val);
 750                 retv = 0;
 751                 break;
 752
 753         case IPV6_MULTICAST_LOOP:
 754                 if (optlen < sizeof(int))
 755                         goto e_inval;
 756                 if (val != valbool)
 757                         goto e_inval;
 758                 np->mc_loop = valbool;
 759                 retv = 0;
 760                 break;
 761
 762         case IPV6_UNICAST_IF:
 763         {
 764                 struct net_device *dev = NULL;
 765                 int ifindex;
 766
 767                 if (optlen != sizeof(int))
 768                         goto e_inval;
 769
 770                 ifindex = (__force int)ntohl((__force __be32)val);
 771                 if (ifindex == 0) {
 772                         np->ucast_oif = 0;
 773                         retv = 0;
 774                         break;
 775                 }
 776
 777                 dev = dev_get_by_index(net, ifindex);
 778                 retv = -EADDRNOTAVAIL;
 779                 if (!dev)
 780                         break;
 781                 dev_put(dev);
 782
 783                 retv = -EINVAL;
 784                 if (sk->sk_bound_dev_if)
 785                         break;
 786
 787                 np->ucast_oif = ifindex;
 788                 retv = 0;
 789                 break;
 790         }
 791
 792         case IPV6_MULTICAST_IF:
 793                 if (sk->sk_type == SOCK_STREAM)
 794                         break;
 795                 if (optlen < sizeof(int))
 796                         goto e_inval;
 797
 798                 if (val) {
 799                         struct net_device *dev;
 800                         int midx;
 801
 802                         rcu_read_lock();
 803
 804                         dev = dev_get_by_index_rcu(net, val);
 805                         if (!dev) {
 806                                 rcu_read_unlock();
 807                                 retv = -ENODEV;
 808                                 break;
 809                         }
 810                         midx = l3mdev_master_ifindex_rcu(dev);
 811
 812                         rcu_read_unlock();
 813
 814                         if (sk->sk_bound_dev_if &&
 815                             sk->sk_bound_dev_if != val &&
 816                             (!midx || midx != sk->sk_bound_dev_if))
 817                                 goto e_inval;
 818                 }
 819                 np->mcast_oif = val;
 820                 retv = 0;
 821                 break;
 822         case IPV6_ADD_MEMBERSHIP:
 823         case IPV6_DROP_MEMBERSHIP:
 824         {
 825                 struct ipv6_mreq mreq;
 826
 827                 if (optlen < sizeof(struct ipv6_mreq))
 828                         goto e_inval;
 829
 830                 retv = -EPROTO;
 831                 if (inet_sk(sk)->is_icsk)
 832                         break;
 833
 834                 retv = -EFAULT;
 835                 if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 836                         break;
 837
 838                 if (optname == IPV6_ADD_MEMBERSHIP)
 839                         retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 840                 else
 841                         retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 842                 break;
 843         }
 844         case IPV6_JOIN_ANYCAST:
 845         case IPV6_LEAVE_ANYCAST:
 846         {
 847                 struct ipv6_mreq mreq;
 848
 849                 if (optlen < sizeof(struct ipv6_mreq))
 850                         goto e_inval;
 851
 852                 retv = -EFAULT;
 853                 if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 854                         break;
 855
 856                 if (optname == IPV6_JOIN_ANYCAST)
 857                         retv = ipv6_sock_ac_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 858                 else
 859                         retv = ipv6_sock_ac_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 860                 break;
 861         }
 862         case IPV6_MULTICAST_ALL:
 863                 if (optlen < sizeof(int))
 864                         goto e_inval;
 865                 np->mc_all = valbool;
 866                 retv = 0;
 867                 break;
 868
 869         case MCAST_JOIN_GROUP:
 870         case MCAST_LEAVE_GROUP:
 871                 if (in_compat_syscall())
 872                         retv = compat_ipv6_mcast_join_leave(sk, optname, optval,
 873                                                             optlen);
 874                 else
 875                         retv = ipv6_mcast_join_leave(sk, optname, optval,
 876                                                      optlen);
 877                 break;
 878         case MCAST_JOIN_SOURCE_GROUP:
 879         case MCAST_LEAVE_SOURCE_GROUP:
 880         case MCAST_BLOCK_SOURCE:
 881         case MCAST_UNBLOCK_SOURCE:
 882                 retv = do_ipv6_mcast_group_source(sk, optname, optval, optlen);
 883                 break;
 884         case MCAST_MSFILTER:
 885                 if (in_compat_syscall())
 886                         retv = compat_ipv6_set_mcast_msfilter(sk, optval,
 887                                                               optlen);
 888                 else
 889                         retv = ipv6_set_mcast_msfilter(sk, optval, optlen);
 890                 break;
 891         case IPV6_ROUTER_ALERT:
 892                 if (optlen < sizeof(int))
 893                         goto e_inval;
 894                 retv = ip6_ra_control(sk, val);
 895                 break;
 896         case IPV6_ROUTER_ALERT_ISOLATE:
 897                 if (optlen < sizeof(int))
 898                         goto e_inval;
 899                 np->rtalert_isolate = valbool;
 900                 retv = 0;
 901                 break;
 902         case IPV6_MTU_DISCOVER:
 903                 if (optlen < sizeof(int))
 904                         goto e_inval;
 905                 if (val < IPV6_PMTUDISC_DONT || val > IPV6_PMTUDISC_OMIT)
 906                         goto e_inval;
 907                 np->pmtudisc = val;
 908                 retv = 0;
 909                 break;
 910         case IPV6_MTU:
 911                 if (optlen < sizeof(int))
 912                         goto e_inval;
 913                 if (val && val < IPV6_MIN_MTU)
 914                         goto e_inval;
 915                 np->frag_size = val;
 916                 retv = 0;
 917                 break;
 918         case IPV6_RECVERR:
 919                 if (optlen < sizeof(int))
 920                         goto e_inval;
 921                 np->recverr = valbool;
 922                 if (!val)
 923                         skb_queue_purge(&sk->sk_error_queue);
 924                 retv = 0;
 925                 break;
 926         case IPV6_FLOWINFO_SEND:
 927                 if (optlen < sizeof(int))
 928                         goto e_inval;
 929                 np->sndflow = valbool;
 930                 retv = 0;
 931                 break;
 932         case IPV6_FLOWLABEL_MGR:
 933                 retv = ipv6_flowlabel_opt(sk, optval, optlen);
 934                 break;
 935         case IPV6_IPSEC_POLICY:
 936         case IPV6_XFRM_POLICY:
 937                 retv = -EPERM;
 938                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 939                         break;
 940                 retv = xfrm_user_policy(sk, optname, optval, optlen);
 941                 break;
 942
 943         case IPV6_ADDR_PREFERENCES:
 944                 if (optlen < sizeof(int))
 945                         goto e_inval;
 946                 retv = __ip6_sock_set_addr_preferences(sk, val);
 947                 break;
 948         case IPV6_MINHOPCOUNT:
 949                 if (optlen < sizeof(int))
 950                         goto e_inval;
 951                 if (val < 0 || val > 255)
 952                         goto e_inval;
 953                 np->min_hopcount = val;
 954                 retv = 0;
 955                 break;
 956         case IPV6_DONTFRAG:
 957                 np->dontfrag = valbool;
 958                 retv = 0;
 959                 break;
 960         case IPV6_AUTOFLOWLABEL:
 961                 np->autoflowlabel = valbool;
 962                 np->autoflowlabel_set = 1;
 963                 retv = 0;
 964                 break;
 965         case IPV6_RECVFRAGSIZE:
 966                 np->rxopt.bits.recvfragsize = valbool;
 967                 retv = 0;
 968                 break;
 969         case IPV6_RECVERR_RFC4884:
 970                 if (optlen < sizeof(int))
 971                         goto e_inval;
 972                 if (val < 0 || val > 1)
 973                         goto e_inval;
 974                 np->recverr_rfc4884 = valbool;
 975                 retv = 0;
 976                 break;
 977         }
 978
 979         release_sock(sk);
 980         if (needs_rtnl)
 981                 rtnl_unlock();
 982
 983         return retv;
 984
 985 e_inval:
 986         release_sock(sk);
 987         if (needs_rtnl)
 988                 rtnl_unlock();
 989         return -EINVAL;
 990 }
 991
 992 int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
 993                     unsigned int optlen)
 994 {
 995         int err;
 996
 997         if (level == SOL_IP && sk->sk_type != SOCK_RAW)
 998                 return udp_prot.setsockopt(sk, level, optname, optval, optlen);
 999
1000         if (level != SOL_IPV6)
1001                 return -ENOPROTOOPT;
1002
1003         err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);
1004 #ifdef CONFIG_NETFILTER
1005         /* we need to exclude all possible ENOPROTOOPTs except default case */
1006         if (err == -ENOPROTOOPT && optname != IPV6_IPSEC_POLICY &&
1007                         optname != IPV6_XFRM_POLICY)
1008                 err = nf_setsockopt(sk, PF_INET6, optname, optval, optlen);
1009 #endif
1010         return err;
1011 }
1012 EXPORT_SYMBOL(ipv6_setsockopt);
1013
1014 static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
1015                                   int optname, char __user *optval, int len)
1016 {
1017         struct ipv6_opt_hdr *hdr;
1018
1019         if (!opt)
1020                 return 0;
1021
1022         switch (optname) {
1023         case IPV6_HOPOPTS:
1024                 hdr = opt->hopopt;
1025                 break;
1026         case IPV6_RTHDRDSTOPTS:
1027                 hdr = opt->dst0opt;
1028                 break;
1029         case IPV6_RTHDR:
1030                 hdr = (struct ipv6_opt_hdr *)opt->srcrt;
1031                 break;
1032         case IPV6_DSTOPTS:
1033                 hdr = opt->dst1opt;
1034                 break;
1035         default:
1036                 return -EINVAL; /* should not happen */
1037         }
1038
1039         if (!hdr)
1040                 return 0;
1041
1042         len = min_t(unsigned int, len, ipv6_optlen(hdr));
1043         if (copy_to_user(optval, hdr, len))
1044                 return -EFAULT;
1045         return len;
1046 }
1047
1048 static int ipv6_get_msfilter(struct sock *sk, void __user *optval,
1049                 int __user *optlen, int len)
1050 {
1051         const int size0 = offsetof(struct group_filter, gf_slist_flex);
1052         struct group_filter __user *p = optval;
1053         struct group_filter gsf;
1054         int num;
1055         int err;
1056
1057         if (len < size0)
1058                 return -EINVAL;
1059         if (copy_from_user(&gsf, p, size0))
1060                 return -EFAULT;
1061         if (gsf.gf_group.ss_family != AF_INET6)
1062                 return -EADDRNOTAVAIL;
1063         num = gsf.gf_numsrc;
1064         lock_sock(sk);
1065         err = ip6_mc_msfget(sk, &gsf, p->gf_slist_flex);
1066         if (!err) {
1067                 if (num > gsf.gf_numsrc)
1068                         num = gsf.gf_numsrc;
1069                 if (put_user(GROUP_FILTER_SIZE(num), optlen) ||
1070                     copy_to_user(p, &gsf, size0))
1071                         err = -EFAULT;
1072         }
1073         release_sock(sk);
1074         return err;
1075 }
1076
1077 static int compat_ipv6_get_msfilter(struct sock *sk, void __user *optval,
1078                 int __user *optlen)
1079 {
1080         const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
1081         struct compat_group_filter __user *p = optval;
1082         struct compat_group_filter gf32;
1083         struct group_filter gf;
1084         int len, err;
1085         int num;
1086
1087         if (get_user(len, optlen))
1088                 return -EFAULT;
1089         if (len < size0)
1090                 return -EINVAL;
1091
1092         if (copy_from_user(&gf32, p, size0))
1093                 return -EFAULT;
1094         gf.gf_interface = gf32.gf_interface;
1095         gf.gf_fmode = gf32.gf_fmode;
1096         num = gf.gf_numsrc = gf32.gf_numsrc;
1097         gf.gf_group = gf32.gf_group;
1098
1099         if (gf.gf_group.ss_family != AF_INET6)
1100                 return -EADDRNOTAVAIL;
1101
1102         lock_sock(sk);
1103         err = ip6_mc_msfget(sk, &gf, p->gf_slist_flex);
1104         release_sock(sk);
1105         if (err)
1106                 return err;
1107         if (num > gf.gf_numsrc)
1108                 num = gf.gf_numsrc;
1109         len = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32));
1110         if (put_user(len, optlen) ||
1111             put_user(gf.gf_fmode, &p->gf_fmode) ||
1112             put_user(gf.gf_numsrc, &p->gf_numsrc))
1113                 return -EFAULT;
1114         return 0;
1115 }
1116
1117 static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
1118                     char __user *optval, int __user *optlen, unsigned int flags)
1119 {
1120         struct ipv6_pinfo *np = inet6_sk(sk);
1121         int len;
1122         int val;
1123
1124         if (ip6_mroute_opt(optname))
1125                 return ip6_mroute_getsockopt(sk, optname, optval, optlen);
1126
1127         if (get_user(len, optlen))
1128                 return -EFAULT;
1129         switch (optname) {
1130         case IPV6_ADDRFORM:
1131                 if (sk->sk_protocol != IPPROTO_UDP &&
1132                     sk->sk_protocol != IPPROTO_UDPLITE &&
1133                     sk->sk_protocol != IPPROTO_TCP)
1134                         return -ENOPROTOOPT;
1135                 if (sk->sk_state != TCP_ESTABLISHED)
1136                         return -ENOTCONN;
1137                 val = sk->sk_family;
1138                 break;
1139         case MCAST_MSFILTER:
1140                 if (in_compat_syscall())
1141                         return compat_ipv6_get_msfilter(sk, optval, optlen);
1142                 return ipv6_get_msfilter(sk, optval, optlen, len);
1143         case IPV6_2292PKTOPTIONS:
1144         {
1145                 struct msghdr msg;
1146                 struct sk_buff *skb;
1147
1148                 if (sk->sk_type != SOCK_STREAM)
1149                         return -ENOPROTOOPT;
1150
1151                 msg.msg_control_user = optval;
1152                 msg.msg_controllen = len;
1153                 msg.msg_flags = flags;
1154                 msg.msg_control_is_user = true;
1155
1156                 lock_sock(sk);
1157                 skb = np->pktoptions;
1158                 if (skb)
1159                         ip6_datagram_recv_ctl(sk, &msg, skb);
1160                 release_sock(sk);
1161                 if (!skb) {
1162                         if (np->rxopt.bits.rxinfo) {
1163                                 struct in6_pktinfo src_info;
1164                                 src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
1165                                         np->sticky_pktinfo.ipi6_ifindex;
1166                                 src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr : np->sticky_pktinfo.ipi6_addr;
1167                                 put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
1168                         }
1169                         if (np->rxopt.bits.rxhlim) {
1170                                 int hlim = np->mcast_hops;
1171                                 put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
1172                         }
1173                         if (np->rxopt.bits.rxtclass) {
1174                                 int tclass = (int)ip6_tclass(np->rcv_flowinfo);
1175
1176                                 put_cmsg(&msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
1177                         }
1178                         if (np->rxopt.bits.rxoinfo) {
1179                                 struct in6_pktinfo src_info;
1180                                 src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
1181                                         np->sticky_pktinfo.ipi6_ifindex;
1182                                 src_info.ipi6_addr = np->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 = np->mcast_hops;
1188                                 put_cmsg(&msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
1189                         }
1190                         if (np->rxopt.bits.rxflow) {
1191                                 __be32 flowinfo = np->rcv_flowinfo;
1192
1193                                 put_cmsg(&msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
1194                         }
1195                 }
1196                 len -= msg.msg_controllen;
1197                 return put_user(len, optlen);
1198         }
1199         case IPV6_MTU:
1200         {
1201                 struct dst_entry *dst;
1202
1203                 val = 0;
1204                 rcu_read_lock();
1205                 dst = __sk_dst_get(sk);
1206                 if (dst)
1207                         val = dst_mtu(dst);
1208                 rcu_read_unlock();
1209                 if (!val)
1210                         return -ENOTCONN;
1211                 break;
1212         }
1213
1214         case IPV6_V6ONLY:
1215                 val = sk->sk_ipv6only;
1216                 break;
1217
1218         case IPV6_RECVPKTINFO:
1219                 val = np->rxopt.bits.rxinfo;
1220                 break;
1221
1222         case IPV6_2292PKTINFO:
1223                 val = np->rxopt.bits.rxoinfo;
1224                 break;
1225
1226         case IPV6_RECVHOPLIMIT:
1227                 val = np->rxopt.bits.rxhlim;
1228                 break;
1229
1230         case IPV6_2292HOPLIMIT:
1231                 val = np->rxopt.bits.rxohlim;
1232                 break;
1233
1234         case IPV6_RECVRTHDR:
1235                 val = np->rxopt.bits.srcrt;
1236                 break;
1237
1238         case IPV6_2292RTHDR:
1239                 val = np->rxopt.bits.osrcrt;
1240                 break;
1241
1242         case IPV6_HOPOPTS:
1243         case IPV6_RTHDRDSTOPTS:
1244         case IPV6_RTHDR:
1245         case IPV6_DSTOPTS:
1246         {
1247                 struct ipv6_txoptions *opt;
1248
1249                 lock_sock(sk);
1250                 opt = rcu_dereference_protected(np->opt,
1251                                                 lockdep_sock_is_held(sk));
1252                 len = ipv6_getsockopt_sticky(sk, opt, optname, optval, len);
1253                 release_sock(sk);
1254                 /* check if ipv6_getsockopt_sticky() returns err code */
1255                 if (len < 0)
1256                         return len;
1257                 return put_user(len, optlen);
1258         }
1259
1260         case IPV6_RECVHOPOPTS:
1261                 val = np->rxopt.bits.hopopts;
1262                 break;
1263
1264         case IPV6_2292HOPOPTS:
1265                 val = np->rxopt.bits.ohopopts;
1266                 break;
1267
1268         case IPV6_RECVDSTOPTS:
1269                 val = np->rxopt.bits.dstopts;
1270                 break;
1271
1272         case IPV6_2292DSTOPTS:
1273                 val = np->rxopt.bits.odstopts;
1274                 break;
1275
1276         case IPV6_TCLASS:
1277                 val = np->tclass;
1278                 break;
1279
1280         case IPV6_RECVTCLASS:
1281                 val = np->rxopt.bits.rxtclass;
1282                 break;
1283
1284         case IPV6_FLOWINFO:
1285                 val = np->rxopt.bits.rxflow;
1286                 break;
1287
1288         case IPV6_RECVPATHMTU:
1289                 val = np->rxopt.bits.rxpmtu;
1290                 break;
1291
1292         case IPV6_PATHMTU:
1293         {
1294                 struct dst_entry *dst;
1295                 struct ip6_mtuinfo mtuinfo;
1296
1297                 if (len < sizeof(mtuinfo))
1298                         return -EINVAL;
1299
1300                 len = sizeof(mtuinfo);
1301                 memset(&mtuinfo, 0, sizeof(mtuinfo));
1302
1303                 rcu_read_lock();
1304                 dst = __sk_dst_get(sk);
1305                 if (dst)
1306                         mtuinfo.ip6m_mtu = dst_mtu(dst);
1307                 rcu_read_unlock();
1308                 if (!mtuinfo.ip6m_mtu)
1309                         return -ENOTCONN;
1310
1311                 if (put_user(len, optlen))
1312                         return -EFAULT;
1313                 if (copy_to_user(optval, &mtuinfo, len))
1314                         return -EFAULT;
1315
1316                 return 0;
1317         }
1318
1319         case IPV6_TRANSPARENT:
1320                 val = inet_sk(sk)->transparent;
1321                 break;
1322
1323         case IPV6_FREEBIND:
1324                 val = inet_sk(sk)->freebind;
1325                 break;
1326
1327         case IPV6_RECVORIGDSTADDR:
1328                 val = np->rxopt.bits.rxorigdstaddr;
1329                 break;
1330
1331         case IPV6_UNICAST_HOPS:
1332         case IPV6_MULTICAST_HOPS:
1333         {
1334                 struct dst_entry *dst;
1335
1336                 if (optname == IPV6_UNICAST_HOPS)
1337                         val = np->hop_limit;
1338                 else
1339                         val = np->mcast_hops;
1340
1341                 if (val < 0) {
1342                         rcu_read_lock();
1343                         dst = __sk_dst_get(sk);
1344                         if (dst)
1345                                 val = ip6_dst_hoplimit(dst);
1346                         rcu_read_unlock();
1347                 }
1348
1349                 if (val < 0)
1350                         val = sock_net(sk)->ipv6.devconf_all->hop_limit;
1351                 break;
1352         }
1353
1354         case IPV6_MULTICAST_LOOP:
1355                 val = np->mc_loop;
1356                 break;
1357
1358         case IPV6_MULTICAST_IF:
1359                 val = np->mcast_oif;
1360                 break;
1361
1362         case IPV6_MULTICAST_ALL:
1363                 val = np->mc_all;
1364                 break;
1365
1366         case IPV6_UNICAST_IF:
1367                 val = (__force int)htonl((__u32) np->ucast_oif);
1368                 break;
1369
1370         case IPV6_MTU_DISCOVER:
1371                 val = np->pmtudisc;
1372                 break;
1373
1374         case IPV6_RECVERR:
1375                 val = np->recverr;
1376                 break;
1377
1378         case IPV6_FLOWINFO_SEND:
1379                 val = np->sndflow;
1380                 break;
1381
1382         case IPV6_FLOWLABEL_MGR:
1383         {
1384                 struct in6_flowlabel_req freq;
1385                 int flags;
1386
1387                 if (len < sizeof(freq))
1388                         return -EINVAL;
1389
1390                 if (copy_from_user(&freq, optval, sizeof(freq)))
1391                         return -EFAULT;
1392
1393                 if (freq.flr_action != IPV6_FL_A_GET)
1394                         return -EINVAL;
1395
1396                 len = sizeof(freq);
1397                 flags = freq.flr_flags;
1398
1399                 memset(&freq, 0, sizeof(freq));
1400
1401                 val = ipv6_flowlabel_opt_get(sk, &freq, flags);
1402                 if (val < 0)
1403                         return val;
1404
1405                 if (put_user(len, optlen))
1406                         return -EFAULT;
1407                 if (copy_to_user(optval, &freq, len))
1408                         return -EFAULT;
1409
1410                 return 0;
1411         }
1412
1413         case IPV6_ADDR_PREFERENCES:
1414                 val = 0;
1415
1416                 if (np->srcprefs & IPV6_PREFER_SRC_TMP)
1417                         val |= IPV6_PREFER_SRC_TMP;
1418                 else if (np->srcprefs & IPV6_PREFER_SRC_PUBLIC)
1419                         val |= IPV6_PREFER_SRC_PUBLIC;
1420                 else {
1421                         /* XXX: should we return system default? */
1422                         val |= IPV6_PREFER_SRC_PUBTMP_DEFAULT;
1423                 }
1424
1425                 if (np->srcprefs & IPV6_PREFER_SRC_COA)
1426                         val |= IPV6_PREFER_SRC_COA;
1427                 else
1428                         val |= IPV6_PREFER_SRC_HOME;
1429                 break;
1430
1431         case IPV6_MINHOPCOUNT:
1432                 val = np->min_hopcount;
1433                 break;
1434
1435         case IPV6_DONTFRAG:
1436                 val = np->dontfrag;
1437                 break;
1438
1439         case IPV6_AUTOFLOWLABEL:
1440                 val = ip6_autoflowlabel(sock_net(sk), np);
1441                 break;
1442
1443         case IPV6_RECVFRAGSIZE:
1444                 val = np->rxopt.bits.recvfragsize;
1445                 break;
1446
1447         case IPV6_ROUTER_ALERT_ISOLATE:
1448                 val = np->rtalert_isolate;
1449                 break;
1450
1451         case IPV6_RECVERR_RFC4884:
1452                 val = np->recverr_rfc4884;
1453                 break;
1454
1455         default:
1456                 return -ENOPROTOOPT;
1457         }
1458         len = min_t(unsigned int, sizeof(int), len);
1459         if (put_user(len, optlen))
1460                 return -EFAULT;
1461         if (copy_to_user(optval, &val, len))
1462                 return -EFAULT;
1463         return 0;
1464 }
1465
1466 int ipv6_getsockopt(struct sock *sk, int level, int optname,
1467                     char __user *optval, int __user *optlen)
1468 {
1469         int err;
1470
1471         if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1472                 return udp_prot.getsockopt(sk, level, optname, optval, optlen);
1473
1474         if (level != SOL_IPV6)
1475                 return -ENOPROTOOPT;
1476
1477         err = do_ipv6_getsockopt(sk, level, optname, optval, optlen, 0);
1478 #ifdef CONFIG_NETFILTER
1479         /* we need to exclude all possible ENOPROTOOPTs except default case */
1480         if (err == -ENOPROTOOPT && optname != IPV6_2292PKTOPTIONS) {
1481                 int len;
1482
1483                 if (get_user(len, optlen))
1484                         return -EFAULT;
1485
1486                 err = nf_getsockopt(sk, PF_INET6, optname, optval, &len);
1487                 if (err >= 0)
1488                         err = put_user(len, optlen);
1489         }
1490 #endif
1491         return err;
1492 }
1493 EXPORT_SYMBOL(ipv6_getsockopt);