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                 if (retv == 0)
 952                         inet6_assign_bit(RTALERT, sk, valbool);
 953                 break;
 954         case IPV6_FLOWLABEL_MGR:
 955                 retv = ipv6_flowlabel_opt(sk, optval, optlen);
 956                 break;
 957         case IPV6_IPSEC_POLICY:
 958         case IPV6_XFRM_POLICY:
 959                 retv = -EPERM;
 960                 if (!sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN))
 961                         break;
 962                 retv = xfrm_user_policy(sk, optname, optval, optlen);
 963                 break;
 964
 965         case IPV6_RECVFRAGSIZE:
 966                 np->rxopt.bits.recvfragsize = valbool;
 967                 retv = 0;
 968                 break;
 969         }
 970
 971 unlock:
 972         sockopt_release_sock(sk);
 973         if (needs_rtnl)
 974                 rtnl_unlock();
 975
 976         return retv;
 977
 978 e_inval:
 979         retv = -EINVAL;
 980         goto unlock;
 981 }
 982
 983 int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
 984                     unsigned int optlen)
 985 {
 986         int err;
 987
 988         if (level == SOL_IP && sk->sk_type != SOCK_RAW)
 989                 return udp_prot.setsockopt(sk, level, optname, optval, optlen);
 990
 991         if (level != SOL_IPV6)
 992                 return -ENOPROTOOPT;
 993
 994         err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);
 995 #ifdef CONFIG_NETFILTER
 996         /* we need to exclude all possible ENOPROTOOPTs except default case */
 997         if (err == -ENOPROTOOPT && optname != IPV6_IPSEC_POLICY &&
 998                         optname != IPV6_XFRM_POLICY)
 999                 err = nf_setsockopt(sk, PF_INET6, optname, optval, optlen);
1000 #endif
1001         return err;
1002 }
1003 EXPORT_SYMBOL(ipv6_setsockopt);
1004
1005 static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
1006                                   int optname, sockptr_t optval, int len)
1007 {
1008         struct ipv6_opt_hdr *hdr;
1009
1010         if (!opt)
1011                 return 0;
1012
1013         switch (optname) {
1014         case IPV6_HOPOPTS:
1015                 hdr = opt->hopopt;
1016                 break;
1017         case IPV6_RTHDRDSTOPTS:
1018                 hdr = opt->dst0opt;
1019                 break;
1020         case IPV6_RTHDR:
1021                 hdr = (struct ipv6_opt_hdr *)opt->srcrt;
1022                 break;
1023         case IPV6_DSTOPTS:
1024                 hdr = opt->dst1opt;
1025                 break;
1026         default:
1027                 return -EINVAL; /* should not happen */
1028         }
1029
1030         if (!hdr)
1031                 return 0;
1032
1033         len = min_t(unsigned int, len, ipv6_optlen(hdr));
1034         if (copy_to_sockptr(optval, hdr, len))
1035                 return -EFAULT;
1036         return len;
1037 }
1038
1039 static int ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
1040                              sockptr_t optlen, int len)
1041 {
1042         const int size0 = offsetof(struct group_filter, gf_slist_flex);
1043         struct group_filter gsf;
1044         int num;
1045         int err;
1046
1047         if (len < size0)
1048                 return -EINVAL;
1049         if (copy_from_sockptr(&gsf, optval, size0))
1050                 return -EFAULT;
1051         if (gsf.gf_group.ss_family != AF_INET6)
1052                 return -EADDRNOTAVAIL;
1053         num = gsf.gf_numsrc;
1054         sockopt_lock_sock(sk);
1055         err = ip6_mc_msfget(sk, &gsf, optval, size0);
1056         if (!err) {
1057                 if (num > gsf.gf_numsrc)
1058                         num = gsf.gf_numsrc;
1059                 len = GROUP_FILTER_SIZE(num);
1060                 if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
1061                     copy_to_sockptr(optval, &gsf, size0))
1062                         err = -EFAULT;
1063         }
1064         sockopt_release_sock(sk);
1065         return err;
1066 }
1067
1068 static int compat_ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
1069                                     sockptr_t optlen, int len)
1070 {
1071         const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
1072         struct compat_group_filter gf32;
1073         struct group_filter gf;
1074         int err;
1075         int num;
1076
1077         if (len < size0)
1078                 return -EINVAL;
1079
1080         if (copy_from_sockptr(&gf32, optval, size0))
1081                 return -EFAULT;
1082         gf.gf_interface = gf32.gf_interface;
1083         gf.gf_fmode = gf32.gf_fmode;
1084         num = gf.gf_numsrc = gf32.gf_numsrc;
1085         gf.gf_group = gf32.gf_group;
1086
1087         if (gf.gf_group.ss_family != AF_INET6)
1088                 return -EADDRNOTAVAIL;
1089
1090         sockopt_lock_sock(sk);
1091         err = ip6_mc_msfget(sk, &gf, optval, size0);
1092         sockopt_release_sock(sk);
1093         if (err)
1094                 return err;
1095         if (num > gf.gf_numsrc)
1096                 num = gf.gf_numsrc;
1097         len = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32));
1098         if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
1099             copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_fmode),
1100                                    &gf.gf_fmode, sizeof(gf32.gf_fmode)) ||
1101             copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_numsrc),
1102                                    &gf.gf_numsrc, sizeof(gf32.gf_numsrc)))
1103                 return -EFAULT;
1104         return 0;
1105 }
1106
1107 int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
1108                        sockptr_t optval, sockptr_t optlen)
1109 {
1110         struct ipv6_pinfo *np = inet6_sk(sk);
1111         int len;
1112         int val;
1113
1114         if (ip6_mroute_opt(optname))
1115                 return ip6_mroute_getsockopt(sk, optname, optval, optlen);
1116
1117         if (copy_from_sockptr(&len, optlen, sizeof(int)))
1118                 return -EFAULT;
1119         switch (optname) {
1120         case IPV6_ADDRFORM:
1121                 if (sk->sk_protocol != IPPROTO_UDP &&
1122                     sk->sk_protocol != IPPROTO_UDPLITE &&
1123                     sk->sk_protocol != IPPROTO_TCP)
1124                         return -ENOPROTOOPT;
1125                 if (sk->sk_state != TCP_ESTABLISHED)
1126                         return -ENOTCONN;
1127                 val = sk->sk_family;
1128                 break;
1129         case MCAST_MSFILTER:
1130                 if (in_compat_syscall())
1131                         return compat_ipv6_get_msfilter(sk, optval, optlen, len);
1132                 return ipv6_get_msfilter(sk, optval, optlen, len);
1133         case IPV6_2292PKTOPTIONS:
1134         {
1135                 struct msghdr msg;
1136                 struct sk_buff *skb;
1137
1138                 if (sk->sk_type != SOCK_STREAM)
1139                         return -ENOPROTOOPT;
1140
1141                 if (optval.is_kernel) {
1142                         msg.msg_control_is_user = false;
1143                         msg.msg_control = optval.kernel;
1144                 } else {
1145                         msg.msg_control_is_user = true;
1146                         msg.msg_control_user = optval.user;
1147                 }
1148                 msg.msg_controllen = len;
1149                 msg.msg_flags = 0;
1150
1151                 sockopt_lock_sock(sk);
1152                 skb = np->pktoptions;
1153                 if (skb)
1154                         ip6_datagram_recv_ctl(sk, &msg, skb);
1155                 sockopt_release_sock(sk);
1156                 if (!skb) {
1157                         if (np->rxopt.bits.rxinfo) {
1158                                 int mcast_oif = READ_ONCE(np->mcast_oif);
1159                                 struct in6_pktinfo src_info;
1160
1161                                 src_info.ipi6_ifindex = mcast_oif ? :
1162                                         np->sticky_pktinfo.ipi6_ifindex;
1163                                 src_info.ipi6_addr = mcast_oif ? sk->sk_v6_daddr : np->sticky_pktinfo.ipi6_addr;
1164                                 put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
1165                         }
1166                         if (np->rxopt.bits.rxhlim) {
1167                                 int hlim = READ_ONCE(np->mcast_hops);
1168
1169                                 put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
1170                         }
1171                         if (np->rxopt.bits.rxtclass) {
1172                                 int tclass = (int)ip6_tclass(np->rcv_flowinfo);
1173
1174                                 put_cmsg(&msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
1175                         }
1176                         if (np->rxopt.bits.rxoinfo) {
1177                                 int mcast_oif = READ_ONCE(np->mcast_oif);
1178                                 struct in6_pktinfo src_info;
1179
1180                                 src_info.ipi6_ifindex = mcast_oif ? :
1181                                         np->sticky_pktinfo.ipi6_ifindex;
1182                                 src_info.ipi6_addr = mcast_oif ? sk->sk_v6_daddr :
1183                                                                  np->sticky_pktinfo.ipi6_addr;
1184                                 put_cmsg(&msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
1185                         }
1186                         if (np->rxopt.bits.rxohlim) {
1187                                 int hlim = READ_ONCE(np->mcast_hops);
1188
1189                                 put_cmsg(&msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
1190                         }
1191                         if (np->rxopt.bits.rxflow) {
1192                                 __be32 flowinfo = np->rcv_flowinfo;
1193
1194                                 put_cmsg(&msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
1195                         }
1196                 }
1197                 len -= msg.msg_controllen;
1198                 return copy_to_sockptr(optlen, &len, sizeof(int));
1199         }
1200         case IPV6_MTU:
1201         {
1202                 struct dst_entry *dst;
1203
1204                 val = 0;
1205                 rcu_read_lock();
1206                 dst = __sk_dst_get(sk);
1207                 if (dst)
1208                         val = dst_mtu(dst);
1209                 rcu_read_unlock();
1210                 if (!val)
1211                         return -ENOTCONN;
1212                 break;
1213         }
1214
1215         case IPV6_V6ONLY:
1216                 val = sk->sk_ipv6only;
1217                 break;
1218
1219         case IPV6_RECVPKTINFO:
1220                 val = np->rxopt.bits.rxinfo;
1221                 break;
1222
1223         case IPV6_2292PKTINFO:
1224                 val = np->rxopt.bits.rxoinfo;
1225                 break;
1226
1227         case IPV6_RECVHOPLIMIT:
1228                 val = np->rxopt.bits.rxhlim;
1229                 break;
1230
1231         case IPV6_2292HOPLIMIT:
1232                 val = np->rxopt.bits.rxohlim;
1233                 break;
1234
1235         case IPV6_RECVRTHDR:
1236                 val = np->rxopt.bits.srcrt;
1237                 break;
1238
1239         case IPV6_2292RTHDR:
1240                 val = np->rxopt.bits.osrcrt;
1241                 break;
1242
1243         case IPV6_HOPOPTS:
1244         case IPV6_RTHDRDSTOPTS:
1245         case IPV6_RTHDR:
1246         case IPV6_DSTOPTS:
1247         {
1248                 struct ipv6_txoptions *opt;
1249
1250                 sockopt_lock_sock(sk);
1251                 opt = rcu_dereference_protected(np->opt,
1252                                                 lockdep_sock_is_held(sk));
1253                 len = ipv6_getsockopt_sticky(sk, opt, optname, optval, len);
1254                 sockopt_release_sock(sk);
1255                 /* check if ipv6_getsockopt_sticky() returns err code */
1256                 if (len < 0)
1257                         return len;
1258                 return copy_to_sockptr(optlen, &len, sizeof(int));
1259         }
1260
1261         case IPV6_RECVHOPOPTS:
1262                 val = np->rxopt.bits.hopopts;
1263                 break;
1264
1265         case IPV6_2292HOPOPTS:
1266                 val = np->rxopt.bits.ohopopts;
1267                 break;
1268
1269         case IPV6_RECVDSTOPTS:
1270                 val = np->rxopt.bits.dstopts;
1271                 break;
1272
1273         case IPV6_2292DSTOPTS:
1274                 val = np->rxopt.bits.odstopts;
1275                 break;
1276
1277         case IPV6_TCLASS:
1278                 val = np->tclass;
1279                 break;
1280
1281         case IPV6_RECVTCLASS:
1282                 val = np->rxopt.bits.rxtclass;
1283                 break;
1284
1285         case IPV6_FLOWINFO:
1286                 val = np->rxopt.bits.rxflow;
1287                 break;
1288
1289         case IPV6_RECVPATHMTU:
1290                 val = np->rxopt.bits.rxpmtu;
1291                 break;
1292
1293         case IPV6_PATHMTU:
1294         {
1295                 struct dst_entry *dst;
1296                 struct ip6_mtuinfo mtuinfo;
1297
1298                 if (len < sizeof(mtuinfo))
1299                         return -EINVAL;
1300
1301                 len = sizeof(mtuinfo);
1302                 memset(&mtuinfo, 0, sizeof(mtuinfo));
1303
1304                 rcu_read_lock();
1305                 dst = __sk_dst_get(sk);
1306                 if (dst)
1307                         mtuinfo.ip6m_mtu = dst_mtu(dst);
1308                 rcu_read_unlock();
1309                 if (!mtuinfo.ip6m_mtu)
1310                         return -ENOTCONN;
1311
1312                 if (copy_to_sockptr(optlen, &len, sizeof(int)))
1313                         return -EFAULT;
1314                 if (copy_to_sockptr(optval, &mtuinfo, len))
1315                         return -EFAULT;
1316
1317                 return 0;
1318         }
1319
1320         case IPV6_TRANSPARENT:
1321                 val = inet_test_bit(TRANSPARENT, sk);
1322                 break;
1323
1324         case IPV6_FREEBIND:
1325                 val = inet_test_bit(FREEBIND, sk);
1326                 break;
1327
1328         case IPV6_RECVORIGDSTADDR:
1329                 val = np->rxopt.bits.rxorigdstaddr;
1330                 break;
1331
1332         case IPV6_UNICAST_HOPS:
1333         case IPV6_MULTICAST_HOPS:
1334         {
1335                 struct dst_entry *dst;
1336
1337                 if (optname == IPV6_UNICAST_HOPS)
1338                         val = READ_ONCE(np->hop_limit);
1339                 else
1340                         val = READ_ONCE(np->mcast_hops);
1341
1342                 if (val < 0) {
1343                         rcu_read_lock();
1344                         dst = __sk_dst_get(sk);
1345                         if (dst)
1346                                 val = ip6_dst_hoplimit(dst);
1347                         rcu_read_unlock();
1348                 }
1349
1350                 if (val < 0)
1351                         val = READ_ONCE(sock_net(sk)->ipv6.devconf_all->hop_limit);
1352                 break;
1353         }
1354
1355         case IPV6_MULTICAST_LOOP:
1356                 val = inet6_test_bit(MC6_LOOP, sk);
1357                 break;
1358
1359         case IPV6_MULTICAST_IF:
1360                 val = READ_ONCE(np->mcast_oif);
1361                 break;
1362
1363         case IPV6_MULTICAST_ALL:
1364                 val = inet6_test_bit(MC6_ALL, sk);
1365                 break;
1366
1367         case IPV6_UNICAST_IF:
1368                 val = (__force int)htonl((__u32) READ_ONCE(np->ucast_oif));
1369                 break;
1370
1371         case IPV6_MTU_DISCOVER:
1372                 val = READ_ONCE(np->pmtudisc);
1373                 break;
1374
1375         case IPV6_RECVERR:
1376                 val = inet6_test_bit(RECVERR6, sk);
1377                 break;
1378
1379         case IPV6_FLOWINFO_SEND:
1380                 val = inet6_test_bit(SNDFLOW, sk);
1381                 break;
1382
1383         case IPV6_FLOWLABEL_MGR:
1384         {
1385                 struct in6_flowlabel_req freq;
1386                 int flags;
1387
1388                 if (len < sizeof(freq))
1389                         return -EINVAL;
1390
1391                 if (copy_from_sockptr(&freq, optval, sizeof(freq)))
1392                         return -EFAULT;
1393
1394                 if (freq.flr_action != IPV6_FL_A_GET)
1395                         return -EINVAL;
1396
1397                 len = sizeof(freq);
1398                 flags = freq.flr_flags;
1399
1400                 memset(&freq, 0, sizeof(freq));
1401
1402                 val = ipv6_flowlabel_opt_get(sk, &freq, flags);
1403                 if (val < 0)
1404                         return val;
1405
1406                 if (copy_to_sockptr(optlen, &len, sizeof(int)))
1407                         return -EFAULT;
1408                 if (copy_to_sockptr(optval, &freq, len))
1409                         return -EFAULT;
1410
1411                 return 0;
1412         }
1413
1414         case IPV6_ADDR_PREFERENCES:
1415                 {
1416                 u8 srcprefs = READ_ONCE(np->srcprefs);
1417                 val = 0;
1418
1419                 if (srcprefs & IPV6_PREFER_SRC_TMP)
1420                         val |= IPV6_PREFER_SRC_TMP;
1421                 else if (srcprefs & IPV6_PREFER_SRC_PUBLIC)
1422                         val |= IPV6_PREFER_SRC_PUBLIC;
1423                 else {
1424                         /* XXX: should we return system default? */
1425                         val |= IPV6_PREFER_SRC_PUBTMP_DEFAULT;
1426                 }
1427
1428                 if (srcprefs & IPV6_PREFER_SRC_COA)
1429                         val |= IPV6_PREFER_SRC_COA;
1430                 else
1431                         val |= IPV6_PREFER_SRC_HOME;
1432                 break;
1433                 }
1434         case IPV6_MINHOPCOUNT:
1435                 val = READ_ONCE(np->min_hopcount);
1436                 break;
1437
1438         case IPV6_DONTFRAG:
1439                 val = inet6_test_bit(DONTFRAG, sk);
1440                 break;
1441
1442         case IPV6_AUTOFLOWLABEL:
1443                 val = ip6_autoflowlabel(sock_net(sk), sk);
1444                 break;
1445
1446         case IPV6_RECVFRAGSIZE:
1447                 val = np->rxopt.bits.recvfragsize;
1448                 break;
1449
1450         case IPV6_ROUTER_ALERT:
1451                 val = inet6_test_bit(RTALERT, sk);
1452                 break;
1453
1454         case IPV6_ROUTER_ALERT_ISOLATE:
1455                 val = inet6_test_bit(RTALERT_ISOLATE, sk);
1456                 break;
1457
1458         case IPV6_RECVERR_RFC4884:
1459                 val = inet6_test_bit(RECVERR6_RFC4884, sk);
1460                 break;
1461
1462         default:
1463                 return -ENOPROTOOPT;
1464         }
1465         len = min_t(unsigned int, sizeof(int), len);
1466         if (copy_to_sockptr(optlen, &len, sizeof(int)))
1467                 return -EFAULT;
1468         if (copy_to_sockptr(optval, &val, len))
1469                 return -EFAULT;
1470         return 0;
1471 }
1472
1473 int ipv6_getsockopt(struct sock *sk, int level, int optname,
1474                     char __user *optval, int __user *optlen)
1475 {
1476         int err;
1477
1478         if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1479                 return udp_prot.getsockopt(sk, level, optname, optval, optlen);
1480
1481         if (level != SOL_IPV6)
1482                 return -ENOPROTOOPT;
1483
1484         err = do_ipv6_getsockopt(sk, level, optname,
1485                                  USER_SOCKPTR(optval), USER_SOCKPTR(optlen));
1486 #ifdef CONFIG_NETFILTER
1487         /* we need to exclude all possible ENOPROTOOPTs except default case */
1488         if (err == -ENOPROTOOPT && optname != IPV6_2292PKTOPTIONS) {
1489                 int len;
1490
1491                 if (get_user(len, optlen))
1492                         return -EFAULT;
1493
1494                 err = nf_getsockopt(sk, PF_INET6, optname, optval, &len);
1495                 if (err >= 0)
1496                         err = put_user(len, optlen);
1497         }
1498 #endif
1499         return err;
1500 }
1501 EXPORT_SYMBOL(ipv6_getsockopt);