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                         /*
 468                          * Sock is moving from IPv6 to IPv4 (sk_prot), so
 469                          * remove it from the refcnt debug socks count in the
 470                          * original family...
 471                          */
 472                         sk_refcnt_debug_dec(sk);
 473
 474                         if (sk->sk_protocol == IPPROTO_TCP) {
 475                                 struct inet_connection_sock *icsk = inet_csk(sk);
 476
 477                                 sock_prot_inuse_add(net, sk->sk_prot, -1);
 478                                 sock_prot_inuse_add(net, &tcp_prot, 1);
 479
 480                                 /* Paired with READ_ONCE(sk->sk_prot) in inet6_stream_ops */
 481                                 WRITE_ONCE(sk->sk_prot, &tcp_prot);
 482                                 /* Paired with READ_ONCE() in tcp_(get|set)sockopt() */
 483                                 WRITE_ONCE(icsk->icsk_af_ops, &ipv4_specific);
 484                                 sk->sk_socket->ops = &inet_stream_ops;
 485                                 sk->sk_family = PF_INET;
 486                                 tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
 487                         } else {
 488                                 struct proto *prot = &udp_prot;
 489
 490                                 if (sk->sk_protocol == IPPROTO_UDPLITE)
 491                                         prot = &udplite_prot;
 492
 493                                 sock_prot_inuse_add(net, sk->sk_prot, -1);
 494                                 sock_prot_inuse_add(net, prot, 1);
 495
 496                                 /* Paired with READ_ONCE(sk->sk_prot) in inet6_dgram_ops */
 497                                 WRITE_ONCE(sk->sk_prot, prot);
 498                                 sk->sk_socket->ops = &inet_dgram_ops;
 499                                 sk->sk_family = PF_INET;
 500                         }
 501
 502                         /* Disable all options not to allocate memory anymore,
 503                          * but there is still a race.  See the lockless path
 504                          * in udpv6_sendmsg() and ipv6_local_rxpmtu().
 505                          */
 506                         np->rxopt.all = 0;
 507
 508                         inet6_cleanup_sock(sk);
 509
 510                         /*
 511                          * ... and add it to the refcnt debug socks count
 512                          * in the new family. -acme
 513                          */
 514                         sk_refcnt_debug_inc(sk);
 515                         module_put(THIS_MODULE);
 516                         retv = 0;
 517                         break;
 518                 }
 519                 goto e_inval;
 520
 521         case IPV6_V6ONLY:
 522                 if (optlen < sizeof(int) ||
 523                     inet_sk(sk)->inet_num)
 524                         goto e_inval;
 525                 sk->sk_ipv6only = valbool;
 526                 retv = 0;
 527                 break;
 528
 529         case IPV6_RECVPKTINFO:
 530                 if (optlen < sizeof(int))
 531                         goto e_inval;
 532                 np->rxopt.bits.rxinfo = valbool;
 533                 retv = 0;
 534                 break;
 535
 536         case IPV6_2292PKTINFO:
 537                 if (optlen < sizeof(int))
 538                         goto e_inval;
 539                 np->rxopt.bits.rxoinfo = valbool;
 540                 retv = 0;
 541                 break;
 542
 543         case IPV6_RECVHOPLIMIT:
 544                 if (optlen < sizeof(int))
 545                         goto e_inval;
 546                 np->rxopt.bits.rxhlim = valbool;
 547                 retv = 0;
 548                 break;
 549
 550         case IPV6_2292HOPLIMIT:
 551                 if (optlen < sizeof(int))
 552                         goto e_inval;
 553                 np->rxopt.bits.rxohlim = valbool;
 554                 retv = 0;
 555                 break;
 556
 557         case IPV6_RECVRTHDR:
 558                 if (optlen < sizeof(int))
 559                         goto e_inval;
 560                 np->rxopt.bits.srcrt = valbool;
 561                 retv = 0;
 562                 break;
 563
 564         case IPV6_2292RTHDR:
 565                 if (optlen < sizeof(int))
 566                         goto e_inval;
 567                 np->rxopt.bits.osrcrt = valbool;
 568                 retv = 0;
 569                 break;
 570
 571         case IPV6_RECVHOPOPTS:
 572                 if (optlen < sizeof(int))
 573                         goto e_inval;
 574                 np->rxopt.bits.hopopts = valbool;
 575                 retv = 0;
 576                 break;
 577
 578         case IPV6_2292HOPOPTS:
 579                 if (optlen < sizeof(int))
 580                         goto e_inval;
 581                 np->rxopt.bits.ohopopts = valbool;
 582                 retv = 0;
 583                 break;
 584
 585         case IPV6_RECVDSTOPTS:
 586                 if (optlen < sizeof(int))
 587                         goto e_inval;
 588                 np->rxopt.bits.dstopts = valbool;
 589                 retv = 0;
 590                 break;
 591
 592         case IPV6_2292DSTOPTS:
 593                 if (optlen < sizeof(int))
 594                         goto e_inval;
 595                 np->rxopt.bits.odstopts = valbool;
 596                 retv = 0;
 597                 break;
 598
 599         case IPV6_TCLASS:
 600                 if (optlen < sizeof(int))
 601                         goto e_inval;
 602                 if (val < -1 || val > 0xff)
 603                         goto e_inval;
 604                 /* RFC 3542, 6.5: default traffic class of 0x0 */
 605                 if (val == -1)
 606                         val = 0;
 607                 if (sk->sk_type == SOCK_STREAM) {
 608                         val &= ~INET_ECN_MASK;
 609                         val |= np->tclass & INET_ECN_MASK;
 610                 }
 611                 if (np->tclass != val) {
 612                         np->tclass = val;
 613                         sk_dst_reset(sk);
 614                 }
 615                 retv = 0;
 616                 break;
 617
 618         case IPV6_RECVTCLASS:
 619                 if (optlen < sizeof(int))
 620                         goto e_inval;
 621                 np->rxopt.bits.rxtclass = valbool;
 622                 retv = 0;
 623                 break;
 624
 625         case IPV6_FLOWINFO:
 626                 if (optlen < sizeof(int))
 627                         goto e_inval;
 628                 np->rxopt.bits.rxflow = valbool;
 629                 retv = 0;
 630                 break;
 631
 632         case IPV6_RECVPATHMTU:
 633                 if (optlen < sizeof(int))
 634                         goto e_inval;
 635                 np->rxopt.bits.rxpmtu = valbool;
 636                 retv = 0;
 637                 break;
 638
 639         case IPV6_TRANSPARENT:
 640                 if (valbool && !sockopt_ns_capable(net->user_ns, CAP_NET_RAW) &&
 641                     !sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN)) {
 642                         retv = -EPERM;
 643                         break;
 644                 }
 645                 if (optlen < sizeof(int))
 646                         goto e_inval;
 647                 /* we don't have a separate transparent bit for IPV6 we use the one in the IPv4 socket */
 648                 inet_sk(sk)->transparent = valbool;
 649                 retv = 0;
 650                 break;
 651
 652         case IPV6_FREEBIND:
 653                 if (optlen < sizeof(int))
 654                         goto e_inval;
 655                 /* we also don't have a separate freebind bit for IPV6 */
 656                 inet_sk(sk)->freebind = valbool;
 657                 retv = 0;
 658                 break;
 659
 660         case IPV6_RECVORIGDSTADDR:
 661                 if (optlen < sizeof(int))
 662                         goto e_inval;
 663                 np->rxopt.bits.rxorigdstaddr = valbool;
 664                 retv = 0;
 665                 break;
 666
 667         case IPV6_HOPOPTS:
 668         case IPV6_RTHDRDSTOPTS:
 669         case IPV6_RTHDR:
 670         case IPV6_DSTOPTS:
 671                 retv = ipv6_set_opt_hdr(sk, optname, optval, optlen);
 672                 break;
 673
 674         case IPV6_PKTINFO:
 675         {
 676                 struct in6_pktinfo pkt;
 677
 678                 if (optlen == 0)
 679                         goto e_inval;
 680                 else if (optlen < sizeof(struct in6_pktinfo) ||
 681                          sockptr_is_null(optval))
 682                         goto e_inval;
 683
 684                 if (copy_from_sockptr(&pkt, optval, sizeof(pkt))) {
 685                         retv = -EFAULT;
 686                         break;
 687                 }
 688                 if (!sk_dev_equal_l3scope(sk, pkt.ipi6_ifindex))
 689                         goto e_inval;
 690
 691                 np->sticky_pktinfo.ipi6_ifindex = pkt.ipi6_ifindex;
 692                 np->sticky_pktinfo.ipi6_addr = pkt.ipi6_addr;
 693                 retv = 0;
 694                 break;
 695         }
 696
 697         case IPV6_2292PKTOPTIONS:
 698         {
 699                 struct ipv6_txoptions *opt = NULL;
 700                 struct msghdr msg;
 701                 struct flowi6 fl6;
 702                 struct ipcm6_cookie ipc6;
 703
 704                 memset(&fl6, 0, sizeof(fl6));
 705                 fl6.flowi6_oif = sk->sk_bound_dev_if;
 706                 fl6.flowi6_mark = sk->sk_mark;
 707
 708                 if (optlen == 0)
 709                         goto update;
 710
 711                 /* 1K is probably excessive
 712                  * 1K is surely not enough, 2K per standard header is 16K.
 713                  */
 714                 retv = -EINVAL;
 715                 if (optlen > 64*1024)
 716                         break;
 717
 718                 opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL);
 719                 retv = -ENOBUFS;
 720                 if (!opt)
 721                         break;
 722
 723                 memset(opt, 0, sizeof(*opt));
 724                 refcount_set(&opt->refcnt, 1);
 725                 opt->tot_len = sizeof(*opt) + optlen;
 726                 retv = -EFAULT;
 727                 if (copy_from_sockptr(opt + 1, optval, optlen))
 728                         goto done;
 729
 730                 msg.msg_controllen = optlen;
 731                 msg.msg_control = (void *)(opt+1);
 732                 ipc6.opt = opt;
 733
 734                 retv = ip6_datagram_send_ctl(net, sk, &msg, &fl6, &ipc6);
 735                 if (retv)
 736                         goto done;
 737 update:
 738                 retv = 0;
 739                 opt = ipv6_update_options(sk, opt);
 740 done:
 741                 if (opt) {
 742                         atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 743                         txopt_put(opt);
 744                 }
 745                 break;
 746         }
 747         case IPV6_UNICAST_HOPS:
 748                 if (optlen < sizeof(int))
 749                         goto e_inval;
 750                 if (val > 255 || val < -1)
 751                         goto e_inval;
 752                 np->hop_limit = val;
 753                 retv = 0;
 754                 break;
 755
 756         case IPV6_MULTICAST_HOPS:
 757                 if (sk->sk_type == SOCK_STREAM)
 758                         break;
 759                 if (optlen < sizeof(int))
 760                         goto e_inval;
 761                 if (val > 255 || val < -1)
 762                         goto e_inval;
 763                 np->mcast_hops = (val == -1 ? IPV6_DEFAULT_MCASTHOPS : val);
 764                 retv = 0;
 765                 break;
 766
 767         case IPV6_MULTICAST_LOOP:
 768                 if (optlen < sizeof(int))
 769                         goto e_inval;
 770                 if (val != valbool)
 771                         goto e_inval;
 772                 np->mc_loop = valbool;
 773                 retv = 0;
 774                 break;
 775
 776         case IPV6_UNICAST_IF:
 777         {
 778                 struct net_device *dev = NULL;
 779                 int ifindex;
 780
 781                 if (optlen != sizeof(int))
 782                         goto e_inval;
 783
 784                 ifindex = (__force int)ntohl((__force __be32)val);
 785                 if (ifindex == 0) {
 786                         np->ucast_oif = 0;
 787                         retv = 0;
 788                         break;
 789                 }
 790
 791                 dev = dev_get_by_index(net, ifindex);
 792                 retv = -EADDRNOTAVAIL;
 793                 if (!dev)
 794                         break;
 795                 dev_put(dev);
 796
 797                 retv = -EINVAL;
 798                 if (sk->sk_bound_dev_if)
 799                         break;
 800
 801                 np->ucast_oif = ifindex;
 802                 retv = 0;
 803                 break;
 804         }
 805
 806         case IPV6_MULTICAST_IF:
 807                 if (sk->sk_type == SOCK_STREAM)
 808                         break;
 809                 if (optlen < sizeof(int))
 810                         goto e_inval;
 811
 812                 if (val) {
 813                         struct net_device *dev;
 814                         int midx;
 815
 816                         rcu_read_lock();
 817
 818                         dev = dev_get_by_index_rcu(net, val);
 819                         if (!dev) {
 820                                 rcu_read_unlock();
 821                                 retv = -ENODEV;
 822                                 break;
 823                         }
 824                         midx = l3mdev_master_ifindex_rcu(dev);
 825
 826                         rcu_read_unlock();
 827
 828                         if (sk->sk_bound_dev_if &&
 829                             sk->sk_bound_dev_if != val &&
 830                             (!midx || midx != sk->sk_bound_dev_if))
 831                                 goto e_inval;
 832                 }
 833                 np->mcast_oif = val;
 834                 retv = 0;
 835                 break;
 836         case IPV6_ADD_MEMBERSHIP:
 837         case IPV6_DROP_MEMBERSHIP:
 838         {
 839                 struct ipv6_mreq mreq;
 840
 841                 if (optlen < sizeof(struct ipv6_mreq))
 842                         goto e_inval;
 843
 844                 retv = -EPROTO;
 845                 if (inet_sk(sk)->is_icsk)
 846                         break;
 847
 848                 retv = -EFAULT;
 849                 if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 850                         break;
 851
 852                 if (optname == IPV6_ADD_MEMBERSHIP)
 853                         retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 854                 else
 855                         retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 856                 break;
 857         }
 858         case IPV6_JOIN_ANYCAST:
 859         case IPV6_LEAVE_ANYCAST:
 860         {
 861                 struct ipv6_mreq mreq;
 862
 863                 if (optlen < sizeof(struct ipv6_mreq))
 864                         goto e_inval;
 865
 866                 retv = -EFAULT;
 867                 if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 868                         break;
 869
 870                 if (optname == IPV6_JOIN_ANYCAST)
 871                         retv = ipv6_sock_ac_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 872                 else
 873                         retv = ipv6_sock_ac_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 874                 break;
 875         }
 876         case IPV6_MULTICAST_ALL:
 877                 if (optlen < sizeof(int))
 878                         goto e_inval;
 879                 np->mc_all = valbool;
 880                 retv = 0;
 881                 break;
 882
 883         case MCAST_JOIN_GROUP:
 884         case MCAST_LEAVE_GROUP:
 885                 if (in_compat_syscall())
 886                         retv = compat_ipv6_mcast_join_leave(sk, optname, optval,
 887                                                             optlen);
 888                 else
 889                         retv = ipv6_mcast_join_leave(sk, optname, optval,
 890                                                      optlen);
 891                 break;
 892         case MCAST_JOIN_SOURCE_GROUP:
 893         case MCAST_LEAVE_SOURCE_GROUP:
 894         case MCAST_BLOCK_SOURCE:
 895         case MCAST_UNBLOCK_SOURCE:
 896                 retv = do_ipv6_mcast_group_source(sk, optname, optval, optlen);
 897                 break;
 898         case MCAST_MSFILTER:
 899                 if (in_compat_syscall())
 900                         retv = compat_ipv6_set_mcast_msfilter(sk, optval,
 901                                                               optlen);
 902                 else
 903                         retv = ipv6_set_mcast_msfilter(sk, optval, optlen);
 904                 break;
 905         case IPV6_ROUTER_ALERT:
 906                 if (optlen < sizeof(int))
 907                         goto e_inval;
 908                 retv = ip6_ra_control(sk, val);
 909                 break;
 910         case IPV6_ROUTER_ALERT_ISOLATE:
 911                 if (optlen < sizeof(int))
 912                         goto e_inval;
 913                 np->rtalert_isolate = valbool;
 914                 retv = 0;
 915                 break;
 916         case IPV6_MTU_DISCOVER:
 917                 if (optlen < sizeof(int))
 918                         goto e_inval;
 919                 if (val < IPV6_PMTUDISC_DONT || val > IPV6_PMTUDISC_OMIT)
 920                         goto e_inval;
 921                 np->pmtudisc = val;
 922                 retv = 0;
 923                 break;
 924         case IPV6_MTU:
 925                 if (optlen < sizeof(int))
 926                         goto e_inval;
 927                 if (val && val < IPV6_MIN_MTU)
 928                         goto e_inval;
 929                 np->frag_size = val;
 930                 retv = 0;
 931                 break;
 932         case IPV6_RECVERR:
 933                 if (optlen < sizeof(int))
 934                         goto e_inval;
 935                 np->recverr = valbool;
 936                 if (!val)
 937                         skb_queue_purge(&sk->sk_error_queue);
 938                 retv = 0;
 939                 break;
 940         case IPV6_FLOWINFO_SEND:
 941                 if (optlen < sizeof(int))
 942                         goto e_inval;
 943                 np->sndflow = valbool;
 944                 retv = 0;
 945                 break;
 946         case IPV6_FLOWLABEL_MGR:
 947                 retv = ipv6_flowlabel_opt(sk, optval, optlen);
 948                 break;
 949         case IPV6_IPSEC_POLICY:
 950         case IPV6_XFRM_POLICY:
 951                 retv = -EPERM;
 952                 if (!sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN))
 953                         break;
 954                 retv = xfrm_user_policy(sk, optname, optval, optlen);
 955                 break;
 956
 957         case IPV6_ADDR_PREFERENCES:
 958                 if (optlen < sizeof(int))
 959                         goto e_inval;
 960                 retv = __ip6_sock_set_addr_preferences(sk, val);
 961                 break;
 962         case IPV6_MINHOPCOUNT:
 963                 if (optlen < sizeof(int))
 964                         goto e_inval;
 965                 if (val < 0 || val > 255)
 966                         goto e_inval;
 967
 968                 if (val)
 969                         static_branch_enable(&ip6_min_hopcount);
 970
 971                 /* tcp_v6_err() and tcp_v6_rcv() might read min_hopcount
 972                  * while we are changing it.
 973                  */
 974                 WRITE_ONCE(np->min_hopcount, val);
 975                 retv = 0;
 976                 break;
 977         case IPV6_DONTFRAG:
 978                 np->dontfrag = valbool;
 979                 retv = 0;
 980                 break;
 981         case IPV6_AUTOFLOWLABEL:
 982                 np->autoflowlabel = valbool;
 983                 np->autoflowlabel_set = 1;
 984                 retv = 0;
 985                 break;
 986         case IPV6_RECVFRAGSIZE:
 987                 np->rxopt.bits.recvfragsize = valbool;
 988                 retv = 0;
 989                 break;
 990         case IPV6_RECVERR_RFC4884:
 991                 if (optlen < sizeof(int))
 992                         goto e_inval;
 993                 if (val < 0 || val > 1)
 994                         goto e_inval;
 995                 np->recverr_rfc4884 = valbool;
 996                 retv = 0;
 997                 break;
 998         }
 999
1000 unlock:
1001         sockopt_release_sock(sk);
1002         if (needs_rtnl)
1003                 rtnl_unlock();
1004
1005         return retv;
1006
1007 e_inval:
1008         sockopt_release_sock(sk);
1009         if (needs_rtnl)
1010                 rtnl_unlock();
1011         return -EINVAL;
1012 }
1013
1014 int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1015                     unsigned int optlen)
1016 {
1017         int err;
1018
1019         if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1020                 return udp_prot.setsockopt(sk, level, optname, optval, optlen);
1021
1022         if (level != SOL_IPV6)
1023                 return -ENOPROTOOPT;
1024
1025         err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);
1026 #ifdef CONFIG_NETFILTER
1027         /* we need to exclude all possible ENOPROTOOPTs except default case */
1028         if (err == -ENOPROTOOPT && optname != IPV6_IPSEC_POLICY &&
1029                         optname != IPV6_XFRM_POLICY)
1030                 err = nf_setsockopt(sk, PF_INET6, optname, optval, optlen);
1031 #endif
1032         return err;
1033 }
1034 EXPORT_SYMBOL(ipv6_setsockopt);
1035
1036 static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
1037                                   int optname, sockptr_t optval, int len)
1038 {
1039         struct ipv6_opt_hdr *hdr;
1040
1041         if (!opt)
1042                 return 0;
1043
1044         switch (optname) {
1045         case IPV6_HOPOPTS:
1046                 hdr = opt->hopopt;
1047                 break;
1048         case IPV6_RTHDRDSTOPTS:
1049                 hdr = opt->dst0opt;
1050                 break;
1051         case IPV6_RTHDR:
1052                 hdr = (struct ipv6_opt_hdr *)opt->srcrt;
1053                 break;
1054         case IPV6_DSTOPTS:
1055                 hdr = opt->dst1opt;
1056                 break;
1057         default:
1058                 return -EINVAL; /* should not happen */
1059         }
1060
1061         if (!hdr)
1062                 return 0;
1063
1064         len = min_t(unsigned int, len, ipv6_optlen(hdr));
1065         if (copy_to_sockptr(optval, hdr, len))
1066                 return -EFAULT;
1067         return len;
1068 }
1069
1070 static int ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
1071                              sockptr_t optlen, int len)
1072 {
1073         const int size0 = offsetof(struct group_filter, gf_slist_flex);
1074         struct group_filter gsf;
1075         int num;
1076         int err;
1077
1078         if (len < size0)
1079                 return -EINVAL;
1080         if (copy_from_sockptr(&gsf, optval, size0))
1081                 return -EFAULT;
1082         if (gsf.gf_group.ss_family != AF_INET6)
1083                 return -EADDRNOTAVAIL;
1084         num = gsf.gf_numsrc;
1085         sockopt_lock_sock(sk);
1086         err = ip6_mc_msfget(sk, &gsf, optval, size0);
1087         if (!err) {
1088                 if (num > gsf.gf_numsrc)
1089                         num = gsf.gf_numsrc;
1090                 len = GROUP_FILTER_SIZE(num);
1091                 if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
1092                     copy_to_sockptr(optval, &gsf, size0))
1093                         err = -EFAULT;
1094         }
1095         sockopt_release_sock(sk);
1096         return err;
1097 }
1098
1099 static int compat_ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
1100                                     sockptr_t optlen, int len)
1101 {
1102         const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
1103         struct compat_group_filter gf32;
1104         struct group_filter gf;
1105         int err;
1106         int num;
1107
1108         if (len < size0)
1109                 return -EINVAL;
1110
1111         if (copy_from_sockptr(&gf32, optval, size0))
1112                 return -EFAULT;
1113         gf.gf_interface = gf32.gf_interface;
1114         gf.gf_fmode = gf32.gf_fmode;
1115         num = gf.gf_numsrc = gf32.gf_numsrc;
1116         gf.gf_group = gf32.gf_group;
1117
1118         if (gf.gf_group.ss_family != AF_INET6)
1119                 return -EADDRNOTAVAIL;
1120
1121         sockopt_lock_sock(sk);
1122         err = ip6_mc_msfget(sk, &gf, optval, size0);
1123         sockopt_release_sock(sk);
1124         if (err)
1125                 return err;
1126         if (num > gf.gf_numsrc)
1127                 num = gf.gf_numsrc;
1128         len = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32));
1129         if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
1130             copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_fmode),
1131                                    &gf.gf_fmode, sizeof(gf32.gf_fmode)) ||
1132             copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_numsrc),
1133                                    &gf.gf_numsrc, sizeof(gf32.gf_numsrc)))
1134                 return -EFAULT;
1135         return 0;
1136 }
1137
1138 int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
1139                        sockptr_t optval, sockptr_t optlen)
1140 {
1141         struct ipv6_pinfo *np = inet6_sk(sk);
1142         int len;
1143         int val;
1144
1145         if (ip6_mroute_opt(optname))
1146                 return ip6_mroute_getsockopt(sk, optname, optval, optlen);
1147
1148         if (copy_from_sockptr(&len, optlen, sizeof(int)))
1149                 return -EFAULT;
1150         switch (optname) {
1151         case IPV6_ADDRFORM:
1152                 if (sk->sk_protocol != IPPROTO_UDP &&
1153                     sk->sk_protocol != IPPROTO_UDPLITE &&
1154                     sk->sk_protocol != IPPROTO_TCP)
1155                         return -ENOPROTOOPT;
1156                 if (sk->sk_state != TCP_ESTABLISHED)
1157                         return -ENOTCONN;
1158                 val = sk->sk_family;
1159                 break;
1160         case MCAST_MSFILTER:
1161                 if (in_compat_syscall())
1162                         return compat_ipv6_get_msfilter(sk, optval, optlen, len);
1163                 return ipv6_get_msfilter(sk, optval, optlen, len);
1164         case IPV6_2292PKTOPTIONS:
1165         {
1166                 struct msghdr msg;
1167                 struct sk_buff *skb;
1168
1169                 if (sk->sk_type != SOCK_STREAM)
1170                         return -ENOPROTOOPT;
1171
1172                 if (optval.is_kernel) {
1173                         msg.msg_control_is_user = false;
1174                         msg.msg_control = optval.kernel;
1175                 } else {
1176                         msg.msg_control_is_user = true;
1177                         msg.msg_control_user = optval.user;
1178                 }
1179                 msg.msg_controllen = len;
1180                 msg.msg_flags = 0;
1181
1182                 sockopt_lock_sock(sk);
1183                 skb = np->pktoptions;
1184                 if (skb)
1185                         ip6_datagram_recv_ctl(sk, &msg, skb);
1186                 sockopt_release_sock(sk);
1187                 if (!skb) {
1188                         if (np->rxopt.bits.rxinfo) {
1189                                 struct in6_pktinfo src_info;
1190                                 src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
1191                                         np->sticky_pktinfo.ipi6_ifindex;
1192                                 src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr : np->sticky_pktinfo.ipi6_addr;
1193                                 put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
1194                         }
1195                         if (np->rxopt.bits.rxhlim) {
1196                                 int hlim = np->mcast_hops;
1197                                 put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
1198                         }
1199                         if (np->rxopt.bits.rxtclass) {
1200                                 int tclass = (int)ip6_tclass(np->rcv_flowinfo);
1201
1202                                 put_cmsg(&msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
1203                         }
1204                         if (np->rxopt.bits.rxoinfo) {
1205                                 struct in6_pktinfo src_info;
1206                                 src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
1207                                         np->sticky_pktinfo.ipi6_ifindex;
1208                                 src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr :
1209                                                                      np->sticky_pktinfo.ipi6_addr;
1210                                 put_cmsg(&msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
1211                         }
1212                         if (np->rxopt.bits.rxohlim) {
1213                                 int hlim = np->mcast_hops;
1214                                 put_cmsg(&msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
1215                         }
1216                         if (np->rxopt.bits.rxflow) {
1217                                 __be32 flowinfo = np->rcv_flowinfo;
1218
1219                                 put_cmsg(&msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
1220                         }
1221                 }
1222                 len -= msg.msg_controllen;
1223                 return copy_to_sockptr(optlen, &len, sizeof(int));
1224         }
1225         case IPV6_MTU:
1226         {
1227                 struct dst_entry *dst;
1228
1229                 val = 0;
1230                 rcu_read_lock();
1231                 dst = __sk_dst_get(sk);
1232                 if (dst)
1233                         val = dst_mtu(dst);
1234                 rcu_read_unlock();
1235                 if (!val)
1236                         return -ENOTCONN;
1237                 break;
1238         }
1239
1240         case IPV6_V6ONLY:
1241                 val = sk->sk_ipv6only;
1242                 break;
1243
1244         case IPV6_RECVPKTINFO:
1245                 val = np->rxopt.bits.rxinfo;
1246                 break;
1247
1248         case IPV6_2292PKTINFO:
1249                 val = np->rxopt.bits.rxoinfo;
1250                 break;
1251
1252         case IPV6_RECVHOPLIMIT:
1253                 val = np->rxopt.bits.rxhlim;
1254                 break;
1255
1256         case IPV6_2292HOPLIMIT:
1257                 val = np->rxopt.bits.rxohlim;
1258                 break;
1259
1260         case IPV6_RECVRTHDR:
1261                 val = np->rxopt.bits.srcrt;
1262                 break;
1263
1264         case IPV6_2292RTHDR:
1265                 val = np->rxopt.bits.osrcrt;
1266                 break;
1267
1268         case IPV6_HOPOPTS:
1269         case IPV6_RTHDRDSTOPTS:
1270         case IPV6_RTHDR:
1271         case IPV6_DSTOPTS:
1272         {
1273                 struct ipv6_txoptions *opt;
1274
1275                 sockopt_lock_sock(sk);
1276                 opt = rcu_dereference_protected(np->opt,
1277                                                 lockdep_sock_is_held(sk));
1278                 len = ipv6_getsockopt_sticky(sk, opt, optname, optval, len);
1279                 sockopt_release_sock(sk);
1280                 /* check if ipv6_getsockopt_sticky() returns err code */
1281                 if (len < 0)
1282                         return len;
1283                 return copy_to_sockptr(optlen, &len, sizeof(int));
1284         }
1285
1286         case IPV6_RECVHOPOPTS:
1287                 val = np->rxopt.bits.hopopts;
1288                 break;
1289
1290         case IPV6_2292HOPOPTS:
1291                 val = np->rxopt.bits.ohopopts;
1292                 break;
1293
1294         case IPV6_RECVDSTOPTS:
1295                 val = np->rxopt.bits.dstopts;
1296                 break;
1297
1298         case IPV6_2292DSTOPTS:
1299                 val = np->rxopt.bits.odstopts;
1300                 break;
1301
1302         case IPV6_TCLASS:
1303                 val = np->tclass;
1304                 break;
1305
1306         case IPV6_RECVTCLASS:
1307                 val = np->rxopt.bits.rxtclass;
1308                 break;
1309
1310         case IPV6_FLOWINFO:
1311                 val = np->rxopt.bits.rxflow;
1312                 break;
1313
1314         case IPV6_RECVPATHMTU:
1315                 val = np->rxopt.bits.rxpmtu;
1316                 break;
1317
1318         case IPV6_PATHMTU:
1319         {
1320                 struct dst_entry *dst;
1321                 struct ip6_mtuinfo mtuinfo;
1322
1323                 if (len < sizeof(mtuinfo))
1324                         return -EINVAL;
1325
1326                 len = sizeof(mtuinfo);
1327                 memset(&mtuinfo, 0, sizeof(mtuinfo));
1328
1329                 rcu_read_lock();
1330                 dst = __sk_dst_get(sk);
1331                 if (dst)
1332                         mtuinfo.ip6m_mtu = dst_mtu(dst);
1333                 rcu_read_unlock();
1334                 if (!mtuinfo.ip6m_mtu)
1335                         return -ENOTCONN;
1336
1337                 if (copy_to_sockptr(optlen, &len, sizeof(int)))
1338                         return -EFAULT;
1339                 if (copy_to_sockptr(optval, &mtuinfo, len))
1340                         return -EFAULT;
1341
1342                 return 0;
1343         }
1344
1345         case IPV6_TRANSPARENT:
1346                 val = inet_sk(sk)->transparent;
1347                 break;
1348
1349         case IPV6_FREEBIND:
1350                 val = inet_sk(sk)->freebind;
1351                 break;
1352
1353         case IPV6_RECVORIGDSTADDR:
1354                 val = np->rxopt.bits.rxorigdstaddr;
1355                 break;
1356
1357         case IPV6_UNICAST_HOPS:
1358         case IPV6_MULTICAST_HOPS:
1359         {
1360                 struct dst_entry *dst;
1361
1362                 if (optname == IPV6_UNICAST_HOPS)
1363                         val = np->hop_limit;
1364                 else
1365                         val = np->mcast_hops;
1366
1367                 if (val < 0) {
1368                         rcu_read_lock();
1369                         dst = __sk_dst_get(sk);
1370                         if (dst)
1371                                 val = ip6_dst_hoplimit(dst);
1372                         rcu_read_unlock();
1373                 }
1374
1375                 if (val < 0)
1376                         val = sock_net(sk)->ipv6.devconf_all->hop_limit;
1377                 break;
1378         }
1379
1380         case IPV6_MULTICAST_LOOP:
1381                 val = np->mc_loop;
1382                 break;
1383
1384         case IPV6_MULTICAST_IF:
1385                 val = np->mcast_oif;
1386                 break;
1387
1388         case IPV6_MULTICAST_ALL:
1389                 val = np->mc_all;
1390                 break;
1391
1392         case IPV6_UNICAST_IF:
1393                 val = (__force int)htonl((__u32) np->ucast_oif);
1394                 break;
1395
1396         case IPV6_MTU_DISCOVER:
1397                 val = np->pmtudisc;
1398                 break;
1399
1400         case IPV6_RECVERR:
1401                 val = np->recverr;
1402                 break;
1403
1404         case IPV6_FLOWINFO_SEND:
1405                 val = np->sndflow;
1406                 break;
1407
1408         case IPV6_FLOWLABEL_MGR:
1409         {
1410                 struct in6_flowlabel_req freq;
1411                 int flags;
1412
1413                 if (len < sizeof(freq))
1414                         return -EINVAL;
1415
1416                 if (copy_from_sockptr(&freq, optval, sizeof(freq)))
1417                         return -EFAULT;
1418
1419                 if (freq.flr_action != IPV6_FL_A_GET)
1420                         return -EINVAL;
1421
1422                 len = sizeof(freq);
1423                 flags = freq.flr_flags;
1424
1425                 memset(&freq, 0, sizeof(freq));
1426
1427                 val = ipv6_flowlabel_opt_get(sk, &freq, flags);
1428                 if (val < 0)
1429                         return val;
1430
1431                 if (copy_to_sockptr(optlen, &len, sizeof(int)))
1432                         return -EFAULT;
1433                 if (copy_to_sockptr(optval, &freq, len))
1434                         return -EFAULT;
1435
1436                 return 0;
1437         }
1438
1439         case IPV6_ADDR_PREFERENCES:
1440                 val = 0;
1441
1442                 if (np->srcprefs & IPV6_PREFER_SRC_TMP)
1443                         val |= IPV6_PREFER_SRC_TMP;
1444                 else if (np->srcprefs & IPV6_PREFER_SRC_PUBLIC)
1445                         val |= IPV6_PREFER_SRC_PUBLIC;
1446                 else {
1447                         /* XXX: should we return system default? */
1448                         val |= IPV6_PREFER_SRC_PUBTMP_DEFAULT;
1449                 }
1450
1451                 if (np->srcprefs & IPV6_PREFER_SRC_COA)
1452                         val |= IPV6_PREFER_SRC_COA;
1453                 else
1454                         val |= IPV6_PREFER_SRC_HOME;
1455                 break;
1456
1457         case IPV6_MINHOPCOUNT:
1458                 val = np->min_hopcount;
1459                 break;
1460
1461         case IPV6_DONTFRAG:
1462                 val = np->dontfrag;
1463                 break;
1464
1465         case IPV6_AUTOFLOWLABEL:
1466                 val = ip6_autoflowlabel(sock_net(sk), np);
1467                 break;
1468
1469         case IPV6_RECVFRAGSIZE:
1470                 val = np->rxopt.bits.recvfragsize;
1471                 break;
1472
1473         case IPV6_ROUTER_ALERT_ISOLATE:
1474                 val = np->rtalert_isolate;
1475                 break;
1476
1477         case IPV6_RECVERR_RFC4884:
1478                 val = np->recverr_rfc4884;
1479                 break;
1480
1481         default:
1482                 return -ENOPROTOOPT;
1483         }
1484         len = min_t(unsigned int, sizeof(int), len);
1485         if (copy_to_sockptr(optlen, &len, sizeof(int)))
1486                 return -EFAULT;
1487         if (copy_to_sockptr(optval, &val, len))
1488                 return -EFAULT;
1489         return 0;
1490 }
1491
1492 int ipv6_getsockopt(struct sock *sk, int level, int optname,
1493                     char __user *optval, int __user *optlen)
1494 {
1495         int err;
1496
1497         if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1498                 return udp_prot.getsockopt(sk, level, optname, optval, optlen);
1499
1500         if (level != SOL_IPV6)
1501                 return -ENOPROTOOPT;
1502
1503         err = do_ipv6_getsockopt(sk, level, optname,
1504                                  USER_SOCKPTR(optval), USER_SOCKPTR(optlen));
1505 #ifdef CONFIG_NETFILTER
1506         /* we need to exclude all possible ENOPROTOOPTs except default case */
1507         if (err == -ENOPROTOOPT && optname != IPV6_2292PKTOPTIONS) {
1508                 int len;
1509
1510                 if (get_user(len, optlen))
1511                         return -EFAULT;
1512
1513                 err = nf_getsockopt(sk, PF_INET6, optname, optval, &len);
1514                 if (err >= 0)
1515                         err = put_user(len, optlen);
1516         }
1517 #endif
1518         return err;
1519 }
1520 EXPORT_SYMBOL(ipv6_getsockopt);