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_test_bit(IS_ICSK, sk)) {
 106                 if (opt &&
 107                     !((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) &&
 108                     inet_sk(sk)->inet_daddr != LOOPBACK4_IPV6) {
 109                         struct inet_connection_sock *icsk = inet_csk(sk);
 110                         icsk->icsk_ext_hdr_len = opt->opt_flen + opt->opt_nflen;
 111                         icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
 112                 }
 113         }
 114         opt = xchg((__force struct ipv6_txoptions **)&inet6_sk(sk)->opt,
 115                    opt);
 116         sk_dst_reset(sk);
 117
 118         return opt;
 119 }
 120
 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(sock_net(sk)->core.sysctl_optmem_max))
 214                 return -ENOBUFS;
 215
 216         gsf = memdup_sockptr(optval, optlen);
 217         if (IS_ERR(gsf))
 218                 return PTR_ERR(gsf);
 219
 220         /* numsrc >= (4G-140)/128 overflow in 32 bits */
 221         ret = -ENOBUFS;
 222         if (gsf->gf_numsrc >= 0x1ffffffU ||
 223             gsf->gf_numsrc > sysctl_mld_max_msf)
 224                 goto out_free_gsf;
 225
 226         ret = -EINVAL;
 227         if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen)
 228                 goto out_free_gsf;
 229
 230         ret = ip6_mc_msfilter(sk, gsf, gsf->gf_slist_flex);
 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(sock_net(sk)->core.sysctl_optmem_max) - 4)
 248                 return -ENOBUFS;
 249
 250         p = kmalloc(optlen + 4, GFP_KERNEL);
 251         if (!p)
 252                 return -ENOMEM;
 253
 254         gf32 = p + 4; /* we want ->gf_group and ->gf_slist_flex aligned */
 255         ret = -EFAULT;
 256         if (copy_from_sockptr(gf32, optval, optlen))
 257                 goto out_free_p;
 258
 259         /* numsrc >= (4G-140)/128 overflow in 32 bits */
 260         ret = -ENOBUFS;
 261         n = gf32->gf_numsrc;
 262         if (n >= 0x1ffffffU || n > sysctl_mld_max_msf)
 263                 goto out_free_p;
 264
 265         ret = -EINVAL;
 266         if (offsetof(struct compat_group_filter, gf_slist_flex[n]) > optlen)
 267                 goto out_free_p;
 268
 269         ret = ip6_mc_msfilter(sk, &(struct group_filter){
 270                         .gf_interface = gf32->gf_interface,
 271                         .gf_group = gf32->gf_group,
 272                         .gf_fmode = gf32->gf_fmode,
 273                         .gf_numsrc = gf32->gf_numsrc}, gf32->gf_slist_flex);
 274
 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         /* Handle options that can be set without locking the socket. */
 419         switch (optname) {
 420         case IPV6_UNICAST_HOPS:
 421                 if (optlen < sizeof(int))
 422                         return -EINVAL;
 423                 if (val > 255 || val < -1)
 424                         return -EINVAL;
 425                 WRITE_ONCE(np->hop_limit, val);
 426                 return 0;
 427         case IPV6_MULTICAST_LOOP:
 428                 if (optlen < sizeof(int))
 429                         return -EINVAL;
 430                 if (val != valbool)
 431                         return -EINVAL;
 432                 inet6_assign_bit(MC6_LOOP, sk, valbool);
 433                 return 0;
 434         case IPV6_MULTICAST_HOPS:
 435                 if (sk->sk_type == SOCK_STREAM)
 436                         return retv;
 437                 if (optlen < sizeof(int))
 438                         return -EINVAL;
 439                 if (val > 255 || val < -1)
 440                         return -EINVAL;
 441                 WRITE_ONCE(np->mcast_hops,
 442                            val == -1 ? IPV6_DEFAULT_MCASTHOPS : val);
 443                 return 0;
 444         case IPV6_MTU:
 445                 if (optlen < sizeof(int))
 446                         return -EINVAL;
 447                 if (val && val < IPV6_MIN_MTU)
 448                         return -EINVAL;
 449                 WRITE_ONCE(np->frag_size, val);
 450                 return 0;
 451         case IPV6_MINHOPCOUNT:
 452                 if (optlen < sizeof(int))
 453                         return -EINVAL;
 454                 if (val < 0 || val > 255)
 455                         return -EINVAL;
 456
 457                 if (val)
 458                         static_branch_enable(&ip6_min_hopcount);
 459
 460                 /* tcp_v6_err() and tcp_v6_rcv() might read min_hopcount
 461                  * while we are changing it.
 462                  */
 463                 WRITE_ONCE(np->min_hopcount, val);
 464                 return 0;
 465         case IPV6_RECVERR_RFC4884:
 466                 if (optlen < sizeof(int))
 467                         return -EINVAL;
 468                 if (val < 0 || val > 1)
 469                         return -EINVAL;
 470                 inet6_assign_bit(RECVERR6_RFC4884, sk, valbool);
 471                 return 0;
 472         case IPV6_MULTICAST_ALL:
 473                 if (optlen < sizeof(int))
 474                         return -EINVAL;
 475                 inet6_assign_bit(MC6_ALL, sk, valbool);
 476                 return 0;
 477         case IPV6_AUTOFLOWLABEL:
 478                 inet6_assign_bit(AUTOFLOWLABEL, sk, valbool);
 479                 inet6_set_bit(AUTOFLOWLABEL_SET, sk);
 480                 return 0;
 481         case IPV6_DONTFRAG:
 482                 inet6_assign_bit(DONTFRAG, sk, valbool);
 483                 return 0;
 484         case IPV6_RECVERR:
 485                 if (optlen < sizeof(int))
 486                         return -EINVAL;
 487                 inet6_assign_bit(RECVERR6, sk, valbool);
 488                 if (!val)
 489                         skb_errqueue_purge(&sk->sk_error_queue);
 490                 return 0;
 491         case IPV6_ROUTER_ALERT_ISOLATE:
 492                 if (optlen < sizeof(int))
 493                         return -EINVAL;
 494                 inet6_assign_bit(RTALERT_ISOLATE, sk, valbool);
 495                 return 0;
 496         case IPV6_MTU_DISCOVER:
 497                 if (optlen < sizeof(int))
 498                         return -EINVAL;
 499                 if (val < IPV6_PMTUDISC_DONT || val > IPV6_PMTUDISC_OMIT)
 500                         return -EINVAL;
 501                 WRITE_ONCE(np->pmtudisc, val);
 502                 return 0;
 503         case IPV6_FLOWINFO_SEND:
 504                 if (optlen < sizeof(int))
 505                         return -EINVAL;
 506                 inet6_assign_bit(SNDFLOW, sk, valbool);
 507                 return 0;
 508         case IPV6_ADDR_PREFERENCES:
 509                 if (optlen < sizeof(int))
 510                         return -EINVAL;
 511                 return ip6_sock_set_addr_preferences(sk, val);
 512         case IPV6_MULTICAST_IF:
 513                 if (sk->sk_type == SOCK_STREAM)
 514                         return -ENOPROTOOPT;
 515                 if (optlen < sizeof(int))
 516                         return -EINVAL;
 517                 if (val) {
 518                         struct net_device *dev;
 519                         int bound_dev_if, midx;
 520
 521                         rcu_read_lock();
 522
 523                         dev = dev_get_by_index_rcu(net, val);
 524                         if (!dev) {
 525                                 rcu_read_unlock();
 526                                 return -ENODEV;
 527                         }
 528                         midx = l3mdev_master_ifindex_rcu(dev);
 529
 530                         rcu_read_unlock();
 531
 532                         bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
 533                         if (bound_dev_if &&
 534                             bound_dev_if != val &&
 535                             (!midx || midx != bound_dev_if))
 536                                 return -EINVAL;
 537                 }
 538                 WRITE_ONCE(np->mcast_oif, val);
 539                 return 0;
 540         case IPV6_UNICAST_IF:
 541         {
 542                 struct net_device *dev;
 543                 int ifindex;
 544
 545                 if (optlen != sizeof(int))
 546                         return -EINVAL;
 547
 548                 ifindex = (__force int)ntohl((__force __be32)val);
 549                 if (!ifindex) {
 550                         WRITE_ONCE(np->ucast_oif, 0);
 551                         return 0;
 552                 }
 553
 554                 dev = dev_get_by_index(net, ifindex);
 555                 if (!dev)
 556                         return -EADDRNOTAVAIL;
 557                 dev_put(dev);
 558
 559                 if (READ_ONCE(sk->sk_bound_dev_if))
 560                         return -EINVAL;
 561
 562                 WRITE_ONCE(np->ucast_oif, ifindex);
 563                 return 0;
 564         }
 565         }
 566         if (needs_rtnl)
 567                 rtnl_lock();
 568         sockopt_lock_sock(sk);
 569
 570         /* Another thread has converted the socket into IPv4 with
 571          * IPV6_ADDRFORM concurrently.
 572          */
 573         if (unlikely(sk->sk_family != AF_INET6))
 574                 goto unlock;
 575
 576         switch (optname) {
 577
 578         case IPV6_ADDRFORM:
 579                 if (optlen < sizeof(int))
 580                         goto e_inval;
 581                 if (val == PF_INET) {
 582                         if (sk->sk_type == SOCK_RAW)
 583                                 break;
 584
 585                         if (sk->sk_protocol == IPPROTO_UDP ||
 586                             sk->sk_protocol == IPPROTO_UDPLITE) {
 587                                 struct udp_sock *up = udp_sk(sk);
 588                                 if (up->pending == AF_INET6) {
 589                                         retv = -EBUSY;
 590                                         break;
 591                                 }
 592                         } else if (sk->sk_protocol == IPPROTO_TCP) {
 593                                 if (sk->sk_prot != &tcpv6_prot) {
 594                                         retv = -EBUSY;
 595                                         break;
 596                                 }
 597                         } else {
 598                                 break;
 599                         }
 600
 601                         if (sk->sk_state != TCP_ESTABLISHED) {
 602                                 retv = -ENOTCONN;
 603                                 break;
 604                         }
 605
 606                         if (ipv6_only_sock(sk) ||
 607                             !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) {
 608                                 retv = -EADDRNOTAVAIL;
 609                                 break;
 610                         }
 611
 612                         __ipv6_sock_mc_close(sk);
 613                         __ipv6_sock_ac_close(sk);
 614
 615                         if (sk->sk_protocol == IPPROTO_TCP) {
 616                                 struct inet_connection_sock *icsk = inet_csk(sk);
 617
 618                                 sock_prot_inuse_add(net, sk->sk_prot, -1);
 619                                 sock_prot_inuse_add(net, &tcp_prot, 1);
 620
 621                                 /* Paired with READ_ONCE(sk->sk_prot) in inet6_stream_ops */
 622                                 WRITE_ONCE(sk->sk_prot, &tcp_prot);
 623                                 /* Paired with READ_ONCE() in tcp_(get|set)sockopt() */
 624                                 WRITE_ONCE(icsk->icsk_af_ops, &ipv4_specific);
 625                                 WRITE_ONCE(sk->sk_socket->ops, &inet_stream_ops);
 626                                 WRITE_ONCE(sk->sk_family, PF_INET);
 627                                 tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
 628                         } else {
 629                                 struct proto *prot = &udp_prot;
 630
 631                                 if (sk->sk_protocol == IPPROTO_UDPLITE)
 632                                         prot = &udplite_prot;
 633
 634                                 sock_prot_inuse_add(net, sk->sk_prot, -1);
 635                                 sock_prot_inuse_add(net, prot, 1);
 636
 637                                 /* Paired with READ_ONCE(sk->sk_prot) in inet6_dgram_ops */
 638                                 WRITE_ONCE(sk->sk_prot, prot);
 639                                 WRITE_ONCE(sk->sk_socket->ops, &inet_dgram_ops);
 640                                 WRITE_ONCE(sk->sk_family, PF_INET);
 641                         }
 642
 643                         /* Disable all options not to allocate memory anymore,
 644                          * but there is still a race.  See the lockless path
 645                          * in udpv6_sendmsg() and ipv6_local_rxpmtu().
 646                          */
 647                         np->rxopt.all = 0;
 648
 649                         inet6_cleanup_sock(sk);
 650
 651                         module_put(THIS_MODULE);
 652                         retv = 0;
 653                         break;
 654                 }
 655                 goto e_inval;
 656
 657         case IPV6_V6ONLY:
 658                 if (optlen < sizeof(int) ||
 659                     inet_sk(sk)->inet_num)
 660                         goto e_inval;
 661                 sk->sk_ipv6only = valbool;
 662                 retv = 0;
 663                 break;
 664
 665         case IPV6_RECVPKTINFO:
 666                 if (optlen < sizeof(int))
 667                         goto e_inval;
 668                 np->rxopt.bits.rxinfo = valbool;
 669                 retv = 0;
 670                 break;
 671
 672         case IPV6_2292PKTINFO:
 673                 if (optlen < sizeof(int))
 674                         goto e_inval;
 675                 np->rxopt.bits.rxoinfo = valbool;
 676                 retv = 0;
 677                 break;
 678
 679         case IPV6_RECVHOPLIMIT:
 680                 if (optlen < sizeof(int))
 681                         goto e_inval;
 682                 np->rxopt.bits.rxhlim = valbool;
 683                 retv = 0;
 684                 break;
 685
 686         case IPV6_2292HOPLIMIT:
 687                 if (optlen < sizeof(int))
 688                         goto e_inval;
 689                 np->rxopt.bits.rxohlim = valbool;
 690                 retv = 0;
 691                 break;
 692
 693         case IPV6_RECVRTHDR:
 694                 if (optlen < sizeof(int))
 695                         goto e_inval;
 696                 np->rxopt.bits.srcrt = valbool;
 697                 retv = 0;
 698                 break;
 699
 700         case IPV6_2292RTHDR:
 701                 if (optlen < sizeof(int))
 702                         goto e_inval;
 703                 np->rxopt.bits.osrcrt = valbool;
 704                 retv = 0;
 705                 break;
 706
 707         case IPV6_RECVHOPOPTS:
 708                 if (optlen < sizeof(int))
 709                         goto e_inval;
 710                 np->rxopt.bits.hopopts = valbool;
 711                 retv = 0;
 712                 break;
 713
 714         case IPV6_2292HOPOPTS:
 715                 if (optlen < sizeof(int))
 716                         goto e_inval;
 717                 np->rxopt.bits.ohopopts = valbool;
 718                 retv = 0;
 719                 break;
 720
 721         case IPV6_RECVDSTOPTS:
 722                 if (optlen < sizeof(int))
 723                         goto e_inval;
 724                 np->rxopt.bits.dstopts = valbool;
 725                 retv = 0;
 726                 break;
 727
 728         case IPV6_2292DSTOPTS:
 729                 if (optlen < sizeof(int))
 730                         goto e_inval;
 731                 np->rxopt.bits.odstopts = valbool;
 732                 retv = 0;
 733                 break;
 734
 735         case IPV6_TCLASS:
 736                 if (optlen < sizeof(int))
 737                         goto e_inval;
 738                 if (val < -1 || val > 0xff)
 739                         goto e_inval;
 740                 /* RFC 3542, 6.5: default traffic class of 0x0 */
 741                 if (val == -1)
 742                         val = 0;
 743                 if (sk->sk_type == SOCK_STREAM) {
 744                         val &= ~INET_ECN_MASK;
 745                         val |= np->tclass & INET_ECN_MASK;
 746                 }
 747                 if (np->tclass != val) {
 748                         np->tclass = val;
 749                         sk_dst_reset(sk);
 750                 }
 751                 retv = 0;
 752                 break;
 753
 754         case IPV6_RECVTCLASS:
 755                 if (optlen < sizeof(int))
 756                         goto e_inval;
 757                 np->rxopt.bits.rxtclass = valbool;
 758                 retv = 0;
 759                 break;
 760
 761         case IPV6_FLOWINFO:
 762                 if (optlen < sizeof(int))
 763                         goto e_inval;
 764                 np->rxopt.bits.rxflow = valbool;
 765                 retv = 0;
 766                 break;
 767
 768         case IPV6_RECVPATHMTU:
 769                 if (optlen < sizeof(int))
 770                         goto e_inval;
 771                 np->rxopt.bits.rxpmtu = valbool;
 772                 retv = 0;
 773                 break;
 774
 775         case IPV6_TRANSPARENT:
 776                 if (valbool && !sockopt_ns_capable(net->user_ns, CAP_NET_RAW) &&
 777                     !sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN)) {
 778                         retv = -EPERM;
 779                         break;
 780                 }
 781                 if (optlen < sizeof(int))
 782                         goto e_inval;
 783                 /* we don't have a separate transparent bit for IPV6 we use the one in the IPv4 socket */
 784                 inet_assign_bit(TRANSPARENT, sk, valbool);
 785                 retv = 0;
 786                 break;
 787
 788         case IPV6_FREEBIND:
 789                 if (optlen < sizeof(int))
 790                         goto e_inval;
 791                 /* we also don't have a separate freebind bit for IPV6 */
 792                 inet_assign_bit(FREEBIND, sk, valbool);
 793                 retv = 0;
 794                 break;
 795
 796         case IPV6_RECVORIGDSTADDR:
 797                 if (optlen < sizeof(int))
 798                         goto e_inval;
 799                 np->rxopt.bits.rxorigdstaddr = valbool;
 800                 retv = 0;
 801                 break;
 802
 803         case IPV6_HOPOPTS:
 804         case IPV6_RTHDRDSTOPTS:
 805         case IPV6_RTHDR:
 806         case IPV6_DSTOPTS:
 807                 retv = ipv6_set_opt_hdr(sk, optname, optval, optlen);
 808                 break;
 809
 810         case IPV6_PKTINFO:
 811         {
 812                 struct in6_pktinfo pkt;
 813
 814                 if (optlen == 0)
 815                         goto e_inval;
 816                 else if (optlen < sizeof(struct in6_pktinfo) ||
 817                          sockptr_is_null(optval))
 818                         goto e_inval;
 819
 820                 if (copy_from_sockptr(&pkt, optval, sizeof(pkt))) {
 821                         retv = -EFAULT;
 822                         break;
 823                 }
 824                 if (!sk_dev_equal_l3scope(sk, pkt.ipi6_ifindex))
 825                         goto e_inval;
 826
 827                 np->sticky_pktinfo.ipi6_ifindex = pkt.ipi6_ifindex;
 828                 np->sticky_pktinfo.ipi6_addr = pkt.ipi6_addr;
 829                 retv = 0;
 830                 break;
 831         }
 832
 833         case IPV6_2292PKTOPTIONS:
 834         {
 835                 struct ipv6_txoptions *opt = NULL;
 836                 struct msghdr msg;
 837                 struct flowi6 fl6;
 838                 struct ipcm6_cookie ipc6;
 839
 840                 memset(&fl6, 0, sizeof(fl6));
 841                 fl6.flowi6_oif = sk->sk_bound_dev_if;
 842                 fl6.flowi6_mark = sk->sk_mark;
 843
 844                 if (optlen == 0)
 845                         goto update;
 846
 847                 /* 1K is probably excessive
 848                  * 1K is surely not enough, 2K per standard header is 16K.
 849                  */
 850                 retv = -EINVAL;
 851                 if (optlen > 64*1024)
 852                         break;
 853
 854                 opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL);
 855                 retv = -ENOBUFS;
 856                 if (!opt)
 857                         break;
 858
 859                 memset(opt, 0, sizeof(*opt));
 860                 refcount_set(&opt->refcnt, 1);
 861                 opt->tot_len = sizeof(*opt) + optlen;
 862                 retv = -EFAULT;
 863                 if (copy_from_sockptr(opt + 1, optval, optlen))
 864                         goto done;
 865
 866                 msg.msg_controllen = optlen;
 867                 msg.msg_control_is_user = false;
 868                 msg.msg_control = (void *)(opt+1);
 869                 ipc6.opt = opt;
 870
 871                 retv = ip6_datagram_send_ctl(net, sk, &msg, &fl6, &ipc6);
 872                 if (retv)
 873                         goto done;
 874 update:
 875                 retv = 0;
 876                 opt = ipv6_update_options(sk, opt);
 877 done:
 878                 if (opt) {
 879                         atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 880                         txopt_put(opt);
 881                 }
 882                 break;
 883         }
 884
 885         case IPV6_ADD_MEMBERSHIP:
 886         case IPV6_DROP_MEMBERSHIP:
 887         {
 888                 struct ipv6_mreq mreq;
 889
 890                 if (optlen < sizeof(struct ipv6_mreq))
 891                         goto e_inval;
 892
 893                 retv = -EPROTO;
 894                 if (inet_test_bit(IS_ICSK, sk))
 895                         break;
 896
 897                 retv = -EFAULT;
 898                 if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 899                         break;
 900
 901                 if (optname == IPV6_ADD_MEMBERSHIP)
 902                         retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 903                 else
 904                         retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 905                 break;
 906         }
 907         case IPV6_JOIN_ANYCAST:
 908         case IPV6_LEAVE_ANYCAST:
 909         {
 910                 struct ipv6_mreq mreq;
 911
 912                 if (optlen < sizeof(struct ipv6_mreq))
 913                         goto e_inval;
 914
 915                 retv = -EFAULT;
 916                 if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 917                         break;
 918
 919                 if (optname == IPV6_JOIN_ANYCAST)
 920                         retv = ipv6_sock_ac_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 921                 else
 922                         retv = ipv6_sock_ac_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 923                 break;
 924         }
 925         case MCAST_JOIN_GROUP:
 926         case MCAST_LEAVE_GROUP:
 927                 if (in_compat_syscall())
 928                         retv = compat_ipv6_mcast_join_leave(sk, optname, optval,
 929                                                             optlen);
 930                 else
 931                         retv = ipv6_mcast_join_leave(sk, optname, optval,
 932                                                      optlen);
 933                 break;
 934         case MCAST_JOIN_SOURCE_GROUP:
 935         case MCAST_LEAVE_SOURCE_GROUP:
 936         case MCAST_BLOCK_SOURCE:
 937         case MCAST_UNBLOCK_SOURCE:
 938                 retv = do_ipv6_mcast_group_source(sk, optname, optval, optlen);
 939                 break;
 940         case MCAST_MSFILTER:
 941                 if (in_compat_syscall())
 942                         retv = compat_ipv6_set_mcast_msfilter(sk, optval,
 943                                                               optlen);
 944                 else
 945                         retv = ipv6_set_mcast_msfilter(sk, optval, optlen);
 946                 break;
 947         case IPV6_ROUTER_ALERT:
 948                 if (optlen < sizeof(int))
 949                         goto e_inval;
 950                 retv = ip6_ra_control(sk, val);
 951                 break;
 952         case IPV6_FLOWLABEL_MGR:
 953                 retv = ipv6_flowlabel_opt(sk, optval, optlen);
 954                 break;
 955         case IPV6_IPSEC_POLICY:
 956         case IPV6_XFRM_POLICY:
 957                 retv = -EPERM;
 958                 if (!sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN))
 959                         break;
 960                 retv = xfrm_user_policy(sk, optname, optval, optlen);
 961                 break;
 962
 963         case IPV6_RECVFRAGSIZE:
 964                 np->rxopt.bits.recvfragsize = valbool;
 965                 retv = 0;
 966                 break;
 967         }
 968
 969 unlock:
 970         sockopt_release_sock(sk);
 971         if (needs_rtnl)
 972                 rtnl_unlock();
 973
 974         return retv;
 975
 976 e_inval:
 977         retv = -EINVAL;
 978         goto unlock;
 979 }
 980
 981 int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
 982                     unsigned int optlen)
 983 {
 984         int err;
 985
 986         if (level == SOL_IP && sk->sk_type != SOCK_RAW)
 987                 return udp_prot.setsockopt(sk, level, optname, optval, optlen);
 988
 989         if (level != SOL_IPV6)
 990                 return -ENOPROTOOPT;
 991
 992         err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);
 993 #ifdef CONFIG_NETFILTER
 994         /* we need to exclude all possible ENOPROTOOPTs except default case */
 995         if (err == -ENOPROTOOPT && optname != IPV6_IPSEC_POLICY &&
 996                         optname != IPV6_XFRM_POLICY)
 997                 err = nf_setsockopt(sk, PF_INET6, optname, optval, optlen);
 998 #endif
 999         return err;
1000 }
1001 EXPORT_SYMBOL(ipv6_setsockopt);
1002
1003 static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
1004                                   int optname, sockptr_t optval, int len)
1005 {
1006         struct ipv6_opt_hdr *hdr;
1007
1008         if (!opt)
1009                 return 0;
1010
1011         switch (optname) {
1012         case IPV6_HOPOPTS:
1013                 hdr = opt->hopopt;
1014                 break;
1015         case IPV6_RTHDRDSTOPTS:
1016                 hdr = opt->dst0opt;
1017                 break;
1018         case IPV6_RTHDR:
1019                 hdr = (struct ipv6_opt_hdr *)opt->srcrt;
1020                 break;
1021         case IPV6_DSTOPTS:
1022                 hdr = opt->dst1opt;
1023                 break;
1024         default:
1025                 return -EINVAL; /* should not happen */
1026         }
1027
1028         if (!hdr)
1029                 return 0;
1030
1031         len = min_t(unsigned int, len, ipv6_optlen(hdr));
1032         if (copy_to_sockptr(optval, hdr, len))
1033                 return -EFAULT;
1034         return len;
1035 }
1036
1037 static int ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
1038                              sockptr_t optlen, int len)
1039 {
1040         const int size0 = offsetof(struct group_filter, gf_slist_flex);
1041         struct group_filter gsf;
1042         int num;
1043         int err;
1044
1045         if (len < size0)
1046                 return -EINVAL;
1047         if (copy_from_sockptr(&gsf, optval, size0))
1048                 return -EFAULT;
1049         if (gsf.gf_group.ss_family != AF_INET6)
1050                 return -EADDRNOTAVAIL;
1051         num = gsf.gf_numsrc;
1052         sockopt_lock_sock(sk);
1053         err = ip6_mc_msfget(sk, &gsf, optval, size0);
1054         if (!err) {
1055                 if (num > gsf.gf_numsrc)
1056                         num = gsf.gf_numsrc;
1057                 len = GROUP_FILTER_SIZE(num);
1058                 if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
1059                     copy_to_sockptr(optval, &gsf, size0))
1060                         err = -EFAULT;
1061         }
1062         sockopt_release_sock(sk);
1063         return err;
1064 }
1065
1066 static int compat_ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
1067                                     sockptr_t optlen, int len)
1068 {
1069         const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
1070         struct compat_group_filter gf32;
1071         struct group_filter gf;
1072         int err;
1073         int num;
1074
1075         if (len < size0)
1076                 return -EINVAL;
1077
1078         if (copy_from_sockptr(&gf32, optval, size0))
1079                 return -EFAULT;
1080         gf.gf_interface = gf32.gf_interface;
1081         gf.gf_fmode = gf32.gf_fmode;
1082         num = gf.gf_numsrc = gf32.gf_numsrc;
1083         gf.gf_group = gf32.gf_group;
1084
1085         if (gf.gf_group.ss_family != AF_INET6)
1086                 return -EADDRNOTAVAIL;
1087
1088         sockopt_lock_sock(sk);
1089         err = ip6_mc_msfget(sk, &gf, optval, size0);
1090         sockopt_release_sock(sk);
1091         if (err)
1092                 return err;
1093         if (num > gf.gf_numsrc)
1094                 num = gf.gf_numsrc;
1095         len = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32));
1096         if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
1097             copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_fmode),
1098                                    &gf.gf_fmode, sizeof(gf32.gf_fmode)) ||
1099             copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_numsrc),
1100                                    &gf.gf_numsrc, sizeof(gf32.gf_numsrc)))
1101                 return -EFAULT;
1102         return 0;
1103 }
1104
1105 int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
1106                        sockptr_t optval, sockptr_t optlen)
1107 {
1108         struct ipv6_pinfo *np = inet6_sk(sk);
1109         int len;
1110         int val;
1111
1112         if (ip6_mroute_opt(optname))
1113                 return ip6_mroute_getsockopt(sk, optname, optval, optlen);
1114
1115         if (copy_from_sockptr(&len, optlen, sizeof(int)))
1116                 return -EFAULT;
1117         switch (optname) {
1118         case IPV6_ADDRFORM:
1119                 if (sk->sk_protocol != IPPROTO_UDP &&
1120                     sk->sk_protocol != IPPROTO_UDPLITE &&
1121                     sk->sk_protocol != IPPROTO_TCP)
1122                         return -ENOPROTOOPT;
1123                 if (sk->sk_state != TCP_ESTABLISHED)
1124                         return -ENOTCONN;
1125                 val = sk->sk_family;
1126                 break;
1127         case MCAST_MSFILTER:
1128                 if (in_compat_syscall())
1129                         return compat_ipv6_get_msfilter(sk, optval, optlen, len);
1130                 return ipv6_get_msfilter(sk, optval, optlen, len);
1131         case IPV6_2292PKTOPTIONS:
1132         {
1133                 struct msghdr msg;
1134                 struct sk_buff *skb;
1135
1136                 if (sk->sk_type != SOCK_STREAM)
1137                         return -ENOPROTOOPT;
1138
1139                 if (optval.is_kernel) {
1140                         msg.msg_control_is_user = false;
1141                         msg.msg_control = optval.kernel;
1142                 } else {
1143                         msg.msg_control_is_user = true;
1144                         msg.msg_control_user = optval.user;
1145                 }
1146                 msg.msg_controllen = len;
1147                 msg.msg_flags = 0;
1148
1149                 sockopt_lock_sock(sk);
1150                 skb = np->pktoptions;
1151                 if (skb)
1152                         ip6_datagram_recv_ctl(sk, &msg, skb);
1153                 sockopt_release_sock(sk);
1154                 if (!skb) {
1155                         if (np->rxopt.bits.rxinfo) {
1156                                 int mcast_oif = READ_ONCE(np->mcast_oif);
1157                                 struct in6_pktinfo src_info;
1158
1159                                 src_info.ipi6_ifindex = mcast_oif ? :
1160                                         np->sticky_pktinfo.ipi6_ifindex;
1161                                 src_info.ipi6_addr = mcast_oif ? sk->sk_v6_daddr : np->sticky_pktinfo.ipi6_addr;
1162                                 put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
1163                         }
1164                         if (np->rxopt.bits.rxhlim) {
1165                                 int hlim = READ_ONCE(np->mcast_hops);
1166
1167                                 put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
1168                         }
1169                         if (np->rxopt.bits.rxtclass) {
1170                                 int tclass = (int)ip6_tclass(np->rcv_flowinfo);
1171
1172                                 put_cmsg(&msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
1173                         }
1174                         if (np->rxopt.bits.rxoinfo) {
1175                                 int mcast_oif = READ_ONCE(np->mcast_oif);
1176                                 struct in6_pktinfo src_info;
1177
1178                                 src_info.ipi6_ifindex = mcast_oif ? :
1179                                         np->sticky_pktinfo.ipi6_ifindex;
1180                                 src_info.ipi6_addr = mcast_oif ? sk->sk_v6_daddr :
1181                                                                  np->sticky_pktinfo.ipi6_addr;
1182                                 put_cmsg(&msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
1183                         }
1184                         if (np->rxopt.bits.rxohlim) {
1185                                 int hlim = READ_ONCE(np->mcast_hops);
1186
1187                                 put_cmsg(&msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
1188                         }
1189                         if (np->rxopt.bits.rxflow) {
1190                                 __be32 flowinfo = np->rcv_flowinfo;
1191
1192                                 put_cmsg(&msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
1193                         }
1194                 }
1195                 len -= msg.msg_controllen;
1196                 return copy_to_sockptr(optlen, &len, sizeof(int));
1197         }
1198         case IPV6_MTU:
1199         {
1200                 struct dst_entry *dst;
1201
1202                 val = 0;
1203                 rcu_read_lock();
1204                 dst = __sk_dst_get(sk);
1205                 if (dst)
1206                         val = dst_mtu(dst);
1207                 rcu_read_unlock();
1208                 if (!val)
1209                         return -ENOTCONN;
1210                 break;
1211         }
1212
1213         case IPV6_V6ONLY:
1214                 val = sk->sk_ipv6only;
1215                 break;
1216
1217         case IPV6_RECVPKTINFO:
1218                 val = np->rxopt.bits.rxinfo;
1219                 break;
1220
1221         case IPV6_2292PKTINFO:
1222                 val = np->rxopt.bits.rxoinfo;
1223                 break;
1224
1225         case IPV6_RECVHOPLIMIT:
1226                 val = np->rxopt.bits.rxhlim;
1227                 break;
1228
1229         case IPV6_2292HOPLIMIT:
1230                 val = np->rxopt.bits.rxohlim;
1231                 break;
1232
1233         case IPV6_RECVRTHDR:
1234                 val = np->rxopt.bits.srcrt;
1235                 break;
1236
1237         case IPV6_2292RTHDR:
1238                 val = np->rxopt.bits.osrcrt;
1239                 break;
1240
1241         case IPV6_HOPOPTS:
1242         case IPV6_RTHDRDSTOPTS:
1243         case IPV6_RTHDR:
1244         case IPV6_DSTOPTS:
1245         {
1246                 struct ipv6_txoptions *opt;
1247
1248                 sockopt_lock_sock(sk);
1249                 opt = rcu_dereference_protected(np->opt,
1250                                                 lockdep_sock_is_held(sk));
1251                 len = ipv6_getsockopt_sticky(sk, opt, optname, optval, len);
1252                 sockopt_release_sock(sk);
1253                 /* check if ipv6_getsockopt_sticky() returns err code */
1254                 if (len < 0)
1255                         return len;
1256                 return copy_to_sockptr(optlen, &len, sizeof(int));
1257         }
1258
1259         case IPV6_RECVHOPOPTS:
1260                 val = np->rxopt.bits.hopopts;
1261                 break;
1262
1263         case IPV6_2292HOPOPTS:
1264                 val = np->rxopt.bits.ohopopts;
1265                 break;
1266
1267         case IPV6_RECVDSTOPTS:
1268                 val = np->rxopt.bits.dstopts;
1269                 break;
1270
1271         case IPV6_2292DSTOPTS:
1272                 val = np->rxopt.bits.odstopts;
1273                 break;
1274
1275         case IPV6_TCLASS:
1276                 val = np->tclass;
1277                 break;
1278
1279         case IPV6_RECVTCLASS:
1280                 val = np->rxopt.bits.rxtclass;
1281                 break;
1282
1283         case IPV6_FLOWINFO:
1284                 val = np->rxopt.bits.rxflow;
1285                 break;
1286
1287         case IPV6_RECVPATHMTU:
1288                 val = np->rxopt.bits.rxpmtu;
1289                 break;
1290
1291         case IPV6_PATHMTU:
1292         {
1293                 struct dst_entry *dst;
1294                 struct ip6_mtuinfo mtuinfo;
1295
1296                 if (len < sizeof(mtuinfo))
1297                         return -EINVAL;
1298
1299                 len = sizeof(mtuinfo);
1300                 memset(&mtuinfo, 0, sizeof(mtuinfo));
1301
1302                 rcu_read_lock();
1303                 dst = __sk_dst_get(sk);
1304                 if (dst)
1305                         mtuinfo.ip6m_mtu = dst_mtu(dst);
1306                 rcu_read_unlock();
1307                 if (!mtuinfo.ip6m_mtu)
1308                         return -ENOTCONN;
1309
1310                 if (copy_to_sockptr(optlen, &len, sizeof(int)))
1311                         return -EFAULT;
1312                 if (copy_to_sockptr(optval, &mtuinfo, len))
1313                         return -EFAULT;
1314
1315                 return 0;
1316         }
1317
1318         case IPV6_TRANSPARENT:
1319                 val = inet_test_bit(TRANSPARENT, sk);
1320                 break;
1321
1322         case IPV6_FREEBIND:
1323                 val = inet_test_bit(FREEBIND, sk);
1324                 break;
1325
1326         case IPV6_RECVORIGDSTADDR:
1327                 val = np->rxopt.bits.rxorigdstaddr;
1328                 break;
1329
1330         case IPV6_UNICAST_HOPS:
1331         case IPV6_MULTICAST_HOPS:
1332         {
1333                 struct dst_entry *dst;
1334
1335                 if (optname == IPV6_UNICAST_HOPS)
1336                         val = READ_ONCE(np->hop_limit);
1337                 else
1338                         val = READ_ONCE(np->mcast_hops);
1339
1340                 if (val < 0) {
1341                         rcu_read_lock();
1342                         dst = __sk_dst_get(sk);
1343                         if (dst)
1344                                 val = ip6_dst_hoplimit(dst);
1345                         rcu_read_unlock();
1346                 }
1347
1348                 if (val < 0)
1349                         val = sock_net(sk)->ipv6.devconf_all->hop_limit;
1350                 break;
1351         }
1352
1353         case IPV6_MULTICAST_LOOP:
1354                 val = inet6_test_bit(MC6_LOOP, sk);
1355                 break;
1356
1357         case IPV6_MULTICAST_IF:
1358                 val = READ_ONCE(np->mcast_oif);
1359                 break;
1360
1361         case IPV6_MULTICAST_ALL:
1362                 val = inet6_test_bit(MC6_ALL, sk);
1363                 break;
1364
1365         case IPV6_UNICAST_IF:
1366                 val = (__force int)htonl((__u32) READ_ONCE(np->ucast_oif));
1367                 break;
1368
1369         case IPV6_MTU_DISCOVER:
1370                 val = READ_ONCE(np->pmtudisc);
1371                 break;
1372
1373         case IPV6_RECVERR:
1374                 val = inet6_test_bit(RECVERR6, sk);
1375                 break;
1376
1377         case IPV6_FLOWINFO_SEND:
1378                 val = inet6_test_bit(SNDFLOW, sk);
1379                 break;
1380
1381         case IPV6_FLOWLABEL_MGR:
1382         {
1383                 struct in6_flowlabel_req freq;
1384                 int flags;
1385
1386                 if (len < sizeof(freq))
1387                         return -EINVAL;
1388
1389                 if (copy_from_sockptr(&freq, optval, sizeof(freq)))
1390                         return -EFAULT;
1391
1392                 if (freq.flr_action != IPV6_FL_A_GET)
1393                         return -EINVAL;
1394
1395                 len = sizeof(freq);
1396                 flags = freq.flr_flags;
1397
1398                 memset(&freq, 0, sizeof(freq));
1399
1400                 val = ipv6_flowlabel_opt_get(sk, &freq, flags);
1401                 if (val < 0)
1402                         return val;
1403
1404                 if (copy_to_sockptr(optlen, &len, sizeof(int)))
1405                         return -EFAULT;
1406                 if (copy_to_sockptr(optval, &freq, len))
1407                         return -EFAULT;
1408
1409                 return 0;
1410         }
1411
1412         case IPV6_ADDR_PREFERENCES:
1413                 {
1414                 u8 srcprefs = READ_ONCE(np->srcprefs);
1415                 val = 0;
1416
1417                 if (srcprefs & IPV6_PREFER_SRC_TMP)
1418                         val |= IPV6_PREFER_SRC_TMP;
1419                 else if (srcprefs & IPV6_PREFER_SRC_PUBLIC)
1420                         val |= IPV6_PREFER_SRC_PUBLIC;
1421                 else {
1422                         /* XXX: should we return system default? */
1423                         val |= IPV6_PREFER_SRC_PUBTMP_DEFAULT;
1424                 }
1425
1426                 if (srcprefs & IPV6_PREFER_SRC_COA)
1427                         val |= IPV6_PREFER_SRC_COA;
1428                 else
1429                         val |= IPV6_PREFER_SRC_HOME;
1430                 break;
1431                 }
1432         case IPV6_MINHOPCOUNT:
1433                 val = READ_ONCE(np->min_hopcount);
1434                 break;
1435
1436         case IPV6_DONTFRAG:
1437                 val = inet6_test_bit(DONTFRAG, sk);
1438                 break;
1439
1440         case IPV6_AUTOFLOWLABEL:
1441                 val = ip6_autoflowlabel(sock_net(sk), sk);
1442                 break;
1443
1444         case IPV6_RECVFRAGSIZE:
1445                 val = np->rxopt.bits.recvfragsize;
1446                 break;
1447
1448         case IPV6_ROUTER_ALERT_ISOLATE:
1449                 val = inet6_test_bit(RTALERT_ISOLATE, sk);
1450                 break;
1451
1452         case IPV6_RECVERR_RFC4884:
1453                 val = inet6_test_bit(RECVERR6_RFC4884, sk);
1454                 break;
1455
1456         default:
1457                 return -ENOPROTOOPT;
1458         }
1459         len = min_t(unsigned int, sizeof(int), len);
1460         if (copy_to_sockptr(optlen, &len, sizeof(int)))
1461                 return -EFAULT;
1462         if (copy_to_sockptr(optval, &val, len))
1463                 return -EFAULT;
1464         return 0;
1465 }
1466
1467 int ipv6_getsockopt(struct sock *sk, int level, int optname,
1468                     char __user *optval, int __user *optlen)
1469 {
1470         int err;
1471
1472         if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1473                 return udp_prot.getsockopt(sk, level, optname, optval, optlen);
1474
1475         if (level != SOL_IPV6)
1476                 return -ENOPROTOOPT;
1477
1478         err = do_ipv6_getsockopt(sk, level, optname,
1479                                  USER_SOCKPTR(optval), USER_SOCKPTR(optlen));
1480 #ifdef CONFIG_NETFILTER
1481         /* we need to exclude all possible ENOPROTOOPTs except default case */
1482         if (err == -ENOPROTOOPT && optname != IPV6_2292PKTOPTIONS) {
1483                 int len;
1484
1485                 if (get_user(len, optlen))
1486                         return -EFAULT;
1487
1488                 err = nf_getsockopt(sk, PF_INET6, optname, optval, &len);
1489                 if (err >= 0)
1490                         err = put_user(len, optlen);
1491         }
1492 #endif
1493         return err;
1494 }
1495 EXPORT_SYMBOL(ipv6_getsockopt);