summaryrefslogtreecommitdiffstats
path: root/net/ipv6/ipv6_sockglue.c
blob: a9895e15ee9c270f13842121b7dc66ed97a71135 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
/*
 *	IPv6 BSD socket options interface
 *	Linux INET6 implementation
 *
 *	Authors:
 *	Pedro Roque		<roque@di.fc.ul.pt>
 *
 *	Based on linux/net/ipv4/ip_sockglue.c
 *
 *	This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 *
 *	FIXME: Make the setsockopt code POSIX compliant: That is
 *
 *	o	Truncate getsockopt returns
 *	o	Return an optlen of the truncated length if need be
 *
 *	Changes:
 *	David L Stevens <dlstevens@us.ibm.com>:
 *		- added multicast source filtering API for MLDv2
 */

#include <linux/module.h>
#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/in6.h>
#include <linux/mroute6.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/init.h>
#include <linux/sysctl.h>
#include <linux/netfilter.h>
#include <linux/slab.h>

#include <net/sock.h>
#include <net/snmp.h>
#include <net/ipv6.h>
#include <net/ndisc.h>
#include <net/protocol.h>
#include <net/transp_v6.h>
#include <net/ip6_route.h>
#include <net/addrconf.h>
#include <net/inet_common.h>
#include <net/tcp.h>
#include <net/udp.h>
#include <net/udplite.h>
#include <net/xfrm.h>
#include <net/compat.h>

#include <asm/uaccess.h>

struct ip6_ra_chain *ip6_ra_chain;
DEFINE_RWLOCK(ip6_ra_lock);

int ip6_ra_control(struct sock *sk, int sel)
{
	struct ip6_ra_chain *ra, *new_ra, **rap;

	/* RA packet may be delivered ONLY to IPPROTO_RAW socket */
	if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num != IPPROTO_RAW)
		return -ENOPROTOOPT;

	new_ra = (sel >= 0) ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;

	write_lock_bh(&ip6_ra_lock);
	for (rap = &ip6_ra_chain; (ra = *rap) != NULL; rap = &ra->next) {
		if (ra->sk == sk) {
			if (sel >= 0) {
				write_unlock_bh(&ip6_ra_lock);
				kfree(new_ra);
				return -EADDRINUSE;
			}

			*rap = ra->next;
			write_unlock_bh(&ip6_ra_lock);

			sock_put(sk);
			kfree(ra);
			return 0;
		}
	}
	if (!new_ra) {
		write_unlock_bh(&ip6_ra_lock);
		return -ENOBUFS;
	}
	new_ra->sk = sk;
	new_ra->sel = sel;
	new_ra->next = ra;
	*rap = new_ra;
	sock_hold(sk);
	write_unlock_bh(&ip6_ra_lock);
	return 0;
}

static
struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
					   struct ipv6_txoptions *opt)
{
	if (inet_sk(sk)->is_icsk) {
		if (opt &&
		    !((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) &&
		    inet_sk(sk)->inet_daddr != LOOPBACK4_IPV6) {
			struct inet_connection_sock *icsk = inet_csk(sk);
			icsk->icsk_ext_hdr_len = opt->opt_flen + opt->opt_nflen;
			icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
		}
	}
	opt = xchg((__force struct ipv6_txoptions **)&inet6_sk(sk)->opt,
		   opt);
	sk_dst_reset(sk);

	return opt;
}

static bool setsockopt_needs_rtnl(int optname)
{
	switch (optname) {
	case IPV6_ADD_MEMBERSHIP:
	case IPV6_DROP_MEMBERSHIP:
	case IPV6_JOIN_ANYCAST:
	case IPV6_LEAVE_ANYCAST:
	case MCAST_JOIN_GROUP:
	case MCAST_LEAVE_GROUP:
	case MCAST_JOIN_SOURCE_GROUP:
	case MCAST_LEAVE_SOURCE_GROUP:
	case MCAST_BLOCK_SOURCE:
	case MCAST_UNBLOCK_SOURCE:
	case MCAST_MSFILTER:
		return true;
	}
	return false;
}

static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
		    char __user *optval, unsigned int optlen)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct net *net = sock_net(sk);
	int val, valbool;
	int retv = -ENOPROTOOPT;
	bool needs_rtnl = setsockopt_needs_rtnl(optname);

	if (!optval)
		val = 0;
	else {
		if (optlen >= sizeof(int)) {
			if (get_user(val, (int __user *) optval))
				return -EFAULT;
		} else
			val = 0;
	}

	valbool = (val != 0);

	if (ip6_mroute_opt(optname))
		return ip6_mroute_setsockopt(sk, optname, optval, optlen);

	if (needs_rtnl)
		rtnl_lock();
	lock_sock(sk);

	switch (optname) {

	case IPV6_ADDRFORM:
		if (optlen < sizeof(int))
			goto e_inval;
		if (val == PF_INET) {
			struct ipv6_txoptions *opt;
			struct sk_buff *pktopt;

			if (sk->sk_type == SOCK_RAW)
				break;

			if (sk->sk_protocol == IPPROTO_UDP ||
			    sk->sk_protocol == IPPROTO_UDPLITE) {
				struct udp_sock *up = udp_sk(sk);
				if (up->pending == AF_INET6) {
					retv = -EBUSY;
					break;
				}
			} else if (sk->sk_protocol != IPPROTO_TCP)
				break;

			if (sk->sk_state != TCP_ESTABLISHED) {
				retv = -ENOTCONN;
				break;
			}

			if (ipv6_only_sock(sk) ||
			    !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) {
				retv = -EADDRNOTAVAIL;
				break;
			}

			fl6_free_socklist(sk);
			ipv6_sock_mc_close(sk);

			/*
			 * Sock is moving from IPv6 to IPv4 (sk_prot), so
			 * remove it from the refcnt debug socks count in the
			 * original family...
			 */
			sk_refcnt_debug_dec(sk);

			if (sk->sk_protocol == IPPROTO_TCP) {
				struct inet_connection_sock *icsk = inet_csk(sk);
				local_bh_disable();
				sock_prot_inuse_add(net, sk->sk_prot, -1);
				sock_prot_inuse_add(net, &tcp_prot, 1);
				local_bh_enable();
				sk->sk_prot = &tcp_prot;
				icsk->icsk_af_ops = &ipv4_specific;
				sk->sk_socket->ops = &inet_stream_ops;
				sk->sk_family = PF_INET;
				tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
			} else {
				struct proto *prot = &udp_prot;

				if (sk->sk_protocol == IPPROTO_UDPLITE)
					prot = &udplite_prot;
				local_bh_disable();
				sock_prot_inuse_add(net, sk->sk_prot, -1);
				sock_prot_inuse_add(net, prot, 1);
				local_bh_enable();
				sk->sk_prot = prot;
				sk->sk_socket->ops = &inet_dgram_ops;
				sk->sk_family = PF_INET;
			}
			opt = xchg((__force struct ipv6_txoptions **)&np->opt,
				   NULL);
			if (opt) {
				atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
				txopt_put(opt);
			}
			pktopt = xchg(&np->pktoptions, NULL);
			kfree_skb(pktopt);

			sk->sk_destruct = inet_sock_destruct;
			/*
			 * ... and add it to the refcnt debug socks count
			 * in the new family. -acme
			 */
			sk_refcnt_debug_inc(sk);
			module_put(THIS_MODULE);
			retv = 0;
			break;
		}
		goto e_inval;

	case IPV6_V6ONLY:
		if (optlen < sizeof(int) ||
		    inet_sk(sk)->inet_num)
			goto e_inval;
		sk->sk_ipv6only = valbool;
		retv = 0;
		break;

	case IPV6_RECVPKTINFO:
		if (optlen < sizeof(int))
			goto e_inval;
		np->rxopt.bits.rxinfo = valbool;
		retv = 0;
		break;

	case IPV6_2292PKTINFO:
		if (optlen < sizeof(int))
			goto e_inval;
		np->rxopt.bits.rxoinfo = valbool;
		retv = 0;
		break;

	case IPV6_RECVHOPLIMIT:
		if (optlen < sizeof(int))
			goto e_inval;
		np->rxopt.bits.rxhlim = valbool;
		retv = 0;
		break;

	case IPV6_2292HOPLIMIT:
		if (optlen < sizeof(int))
			goto e_inval;
		np->rxopt.bits.rxohlim = valbool;
		retv = 0;
		break;

	case IPV6_RECVRTHDR:
		if (optlen < sizeof(int))
			goto e_inval;
		np->rxopt.bits.srcrt = valbool;
		retv = 0;
		break;

	case IPV6_2292RTHDR:
		if (optlen < sizeof(int))
			goto e_inval;
		np->rxopt.bits.osrcrt = valbool;
		retv = 0;
		break;

	case IPV6_RECVHOPOPTS:
		if (optlen < sizeof(int))
			goto e_inval;
		np->rxopt.bits.hopopts = valbool;
		retv = 0;
		break;

	case IPV6_2292HOPOPTS:
		if (optlen < sizeof(int))
			goto e_inval;
		np->rxopt.bits.ohopopts = valbool;
		retv = 0;
		break;

	case IPV6_RECVDSTOPTS:
		if (optlen < sizeof(int))
			goto e_inval;
		np->rxopt.bits.dstopts = valbool;
		retv = 0;
		break;

	case IPV6_2292DSTOPTS:
		if (optlen < sizeof(int))
			goto e_inval;
		np->rxopt.bits.odstopts = valbool;
		retv = 0;
		break;

	case IPV6_TCLASS:
		if (optlen < sizeof(int))
			goto e_inval;
		if (val < -1 || val > 0xff)
			goto e_inval;
		/* RFC 3542, 6.5: default traffic class of 0x0 */
		if (val == -1)
			val = 0;
		np->tclass = val;
		retv = 0;
		break;

	case IPV6_RECVTCLASS:
		if (optlen < sizeof(int))
			goto e_inval;
		np->rxopt.bits.rxtclass = valbool;
		retv = 0;
		break;

	case IPV6_FLOWINFO:
		if (optlen < sizeof(int))
			goto e_inval;
		np->rxopt.bits.rxflow = valbool;
		retv = 0;
		break;

	case IPV6_RECVPATHMTU:
		if (optlen < sizeof(int))
			goto e_inval;
		np->rxopt.bits.rxpmtu = valbool;
		retv = 0;
		break;

	case IPV6_TRANSPARENT:
		if (valbool && !ns_capable(net->user_ns, CAP_NET_ADMIN) &&
		    !ns_capable(net->user_ns, CAP_NET_RAW)) {
			retv = -EPERM;
			break;
		}
		if (optlen < sizeof(int))
			goto e_inval;
		/* we don't have a separate transparent bit for IPV6 we use the one in the IPv4 socket */
		inet_sk(sk)->transparent = valbool;
		retv = 0;
		break;

	case IPV6_RECVORIGDSTADDR:
		if (optlen < sizeof(int))
			goto e_inval;
		np->rxopt.bits.rxorigdstaddr = valbool;
		retv = 0;
		break;

	case IPV6_HOPOPTS:
	case IPV6_RTHDRDSTOPTS:
	case IPV6_RTHDR:
	case IPV6_DSTOPTS:
	{
		struct ipv6_txoptions *opt;

		/* remove any sticky options header with a zero option
		 * length, per RFC3542.
		 */
		if (optlen == 0)
			optval = NULL;
		else if (!optval)
			goto e_inval;
		else if (optlen < sizeof(struct ipv6_opt_hdr) ||
			 optlen & 0x7 || optlen > 8 * 255)
			goto e_inval;

		/* hop-by-hop / destination options are privileged option */
		retv = -EPERM;
		if (optname != IPV6_RTHDR && !ns_capable(net->user_ns, CAP_NET_RAW))
			break;

		opt = rcu_dereference_protected(np->opt,
						lockdep_sock_is_held(sk));
		opt = ipv6_renew_options(sk, opt, optname,
					 (struct ipv6_opt_hdr __user *)optval,
					 optlen);
		if (IS_ERR(opt)) {
			retv = PTR_ERR(opt);
			break;
		}

		/* routing header option needs extra check */
		retv = -EINVAL;
		if (optname == IPV6_RTHDR && opt && opt->srcrt) {
			struct ipv6_rt_hdr *rthdr = opt->srcrt;
			switch (rthdr->type) {
#if IS_ENABLED(CONFIG_IPV6_MIP6)
			case IPV6_SRCRT_TYPE_2:
				if (rthdr->hdrlen != 2 ||
				    rthdr->segments_left != 1)
					goto sticky_done;

				break;
#endif
			default:
				goto sticky_done;
			}
		}

		retv = 0;
		opt = ipv6_update_options(sk, opt);
sticky_done:
		if (opt) {
			atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
			txopt_put(opt);
		}
		break;
	}

	case IPV6_PKTINFO:
	{
		struct in6_pktinfo pkt;

		if (optlen == 0)
			goto e_inval;
		else if (optlen < sizeof(struct in6_pktinfo) || !optval)
			goto e_inval;

		if (copy_from_user(&pkt, optval, sizeof(struct in6_pktinfo))) {
				retv = -EFAULT;
				break;
		}
		if (sk->sk_bound_dev_if && pkt.ipi6_ifindex != sk->sk_bound_dev_if)
			goto e_inval;

		np->sticky_pktinfo.ipi6_ifindex = pkt.ipi6_ifindex;
		np->sticky_pktinfo.ipi6_addr = pkt.ipi6_addr;
		retv = 0;
		break;
	}

	case IPV6_2292PKTOPTIONS:
	{
		struct ipv6_txoptions *opt = NULL;
		struct msghdr msg;
		struct flowi6 fl6;
		struct sockcm_cookie sockc_junk;
		struct ipcm6_cookie ipc6;

		memset(&fl6, 0, sizeof(fl6));
		fl6.flowi6_oif = sk->sk_bound_dev_if;
		fl6.flowi6_mark = sk->sk_mark;

		if (optlen == 0)
			goto update;

		/* 1K is probably excessive
		 * 1K is surely not enough, 2K per standard header is 16K.
		 */
		retv = -EINVAL;
		if (optlen > 64*1024)
			break;

		opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL);
		retv = -ENOBUFS;
		if (!opt)
			break;

		memset(opt, 0, sizeof(*opt));
		atomic_set(&opt->refcnt, 1);
		opt->tot_len = sizeof(*opt) + optlen;
		retv = -EFAULT;
		if (copy_from_user(opt+1, optval, optlen))
			goto done;

		msg.msg_controllen = optlen;
		msg.msg_control = (void *)(opt+1);
		ipc6.opt = opt;

		retv = ip6_datagram_send_ctl(net, sk, &msg, &fl6, &ipc6, &sockc_junk);
		if (retv)
			goto done;
update:
		retv = 0;
		opt = ipv6_update_options(sk, opt);
done:
		if (opt) {
			atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
			txopt_put(opt);
		}
		break;
	}
	case IPV6_UNICAST_HOPS:
		if (optlen < sizeof(int))
			goto e_inval;
		if (val > 255 || val < -1)
			goto e_inval;
		np->hop_limit = val;
		retv = 0;
		break;

	case IPV6_MULTICAST_HOPS:
		if (sk->sk_type == SOCK_STREAM)
			break;
		if (optlen < sizeof(int))
			goto e_inval;
		if (val > 255 || val < -1)
			goto e_inval;
		np->mcast_hops = (val == -1 ? IPV6_DEFAULT_MCASTHOPS : val);
		retv = 0;
		break;

	case IPV6_MULTICAST_LOOP:
		if (optlen < sizeof(int))
			goto e_inval;
		if (val != valbool)
			goto e_inval;
		np->mc_loop = valbool;
		retv = 0;
		break;

	case IPV6_UNICAST_IF:
	{
		struct net_device *dev = NULL;
		int ifindex;

		if (optlen != sizeof(int))
			goto e_inval;

		ifindex = (__force int)ntohl((__force __be32)val);
		if (ifindex == 0) {
			np->ucast_oif = 0;
			retv = 0;
			break;
		}

		dev = dev_get_by_index(net, ifindex);
		retv = -EADDRNOTAVAIL;
		if (!dev)
			break;
		dev_put(dev);

		retv = -EINVAL;
		if (sk->sk_bound_dev_if)
			break;

		np->ucast_oif = ifindex;
		retv = 0;
		break;
	}

	case IPV6_MULTICAST_IF:
		if (sk->sk_type == SOCK_STREAM)
			break;
		if (optlen < sizeof(int))
			goto e_inval;

		if (val) {
			struct net_device *dev;

			if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != val)
				goto e_inval;

			dev = dev_get_by_index(net, val);
			if (!dev) {
				retv = -ENODEV;
				break;
			}
			dev_put(dev);
		}
		np->mcast_oif = val;
		retv = 0;
		break;
	case IPV6_ADD_MEMBERSHIP:
	case IPV6_DROP_MEMBERSHIP:
	{
		struct ipv6_mreq mreq;

		if (optlen < sizeof(struct ipv6_mreq))
			goto e_inval;

		retv = -EPROTO;
		if (inet_sk(sk)->is_icsk)
			break;

		retv = -EFAULT;
		if (copy_from_user(&mreq, optval, sizeof(struct ipv6_mreq)))
			break;

		if (optname == IPV6_ADD_MEMBERSHIP)
			retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
		else
			retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
		break;
	}
	case IPV6_JOIN_ANYCAST:
	case IPV6_LEAVE_ANYCAST:
	{
		struct ipv6_mreq mreq;

		if (optlen < sizeof(struct ipv6_mreq))
			goto e_inval;

		retv = -EFAULT;
		if (copy_from_user(&mreq, optval, sizeof(struct ipv6_mreq)))
			break;

		if (optname == IPV6_JOIN_ANYCAST)
			retv = ipv6_sock_ac_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
		else
			retv = ipv6_sock_ac_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
		break;
	}
	case MCAST_JOIN_GROUP:
	case MCAST_LEAVE_GROUP:
	{
		struct group_req greq;
		struct sockaddr_in6 *psin6;

		if (optlen < sizeof(struct group_req))
			goto e_inval;

		retv = -EFAULT;
		if (copy_from_user(&greq, optval, sizeof(struct group_req)))
			break;
		if (greq.gr_group.ss_family != AF_INET6) {
			retv = -EADDRNOTAVAIL;
			break;
		}
		psin6 = (struct sockaddr_in6 *)&greq.gr_group;
		if (optname == MCAST_JOIN_GROUP)
			retv = ipv6_sock_mc_join(sk, greq.gr_interface,
						 &psin6->sin6_addr);
		else
			retv = ipv6_sock_mc_drop(sk, greq.gr_interface,
						 &psin6->sin6_addr);
		break;
	}
	case MCAST_JOIN_SOURCE_GROUP:
	case MCAST_LEAVE_SOURCE_GROUP:
	case MCAST_BLOCK_SOURCE:
	case MCAST_UNBLOCK_SOURCE:
	{
		struct group_source_req greqs;
		int omode, add;

		if (optlen < sizeof(struct group_source_req))
			goto e_inval;
		if (copy_from_user(&greqs, optval, sizeof(greqs))) {
			retv = -EFAULT;
			break;
		}
		if (greqs.gsr_group.ss_family != AF_INET6 ||
		    greqs.gsr_source.ss_family != AF_INET6) {
			retv = -EADDRNOTAVAIL;
			break;
		}
		if (optname == MCAST_BLOCK_SOURCE) {
			omode = MCAST_EXCLUDE;
			add = 1;
		} else if (optname == MCAST_UNBLOCK_SOURCE) {
			omode = MCAST_EXCLUDE;
			add = 0;
		} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
			struct sockaddr_in6 *psin6;

			psin6 = (struct sockaddr_in6 *)&greqs.gsr_group;
			retv = ipv6_sock_mc_join(sk, greqs.gsr_interface,
						 &psin6->sin6_addr);
			/* prior join w/ different source is ok */
			if (retv && retv != -EADDRINUSE)
				break;
			omode = MCAST_INCLUDE;
			add = 1;
		} else /* MCAST_LEAVE_SOURCE_GROUP */ {
			omode = MCAST_INCLUDE;
			add = 0;
		}
		retv = ip6_mc_source(add, omode, sk, &greqs);
		break;
	}
	case MCAST_MSFILTER:
	{
		struct group_filter *gsf;

		if (optlen < GROUP_FILTER_SIZE(0))
			goto e_inval;
		if (optlen > sysctl_optmem_max) {
			retv = -ENOBUFS;
			break;
		}
		gsf = kmalloc(optlen, GFP_KERNEL);
		if (!gsf) {
			retv = -ENOBUFS;
			break;
		}
		retv = -EFAULT;
		if (copy_from_user(gsf, optval, optlen)) {
			kfree(gsf);
			break;
		}
		/* numsrc >= (4G-140)/128 overflow in 32 bits */
		if (gsf->gf_numsrc >= 0x1ffffffU ||
		    gsf->gf_numsrc > sysctl_mld_max_msf) {
			kfree(gsf);
			retv = -ENOBUFS;
			break;
		}
		if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
			kfree(gsf);
			retv = -EINVAL;
			break;
		}
		retv = ip6_mc_msfilter(sk, gsf);
		kfree(gsf);

		break;
	}
	case IPV6_ROUTER_ALERT:
		if (optlen < sizeof(int))
			goto e_inval;
		retv = ip6_ra_control(sk, val);
		break;
	case IPV6_MTU_DISCOVER:
		if (optlen < sizeof(int))
			goto e_inval;
		if (val < IPV6_PMTUDISC_DONT || val > IPV6_PMTUDISC_OMIT)
			goto e_inval;
		np->pmtudisc = val;
		retv = 0;
		break;
	case IPV6_MTU:
		if (optlen < sizeof(int))
			goto e_inval;
		if (val && val < IPV6_MIN_MTU)
			goto e_inval;
		np->frag_size = val;
		retv = 0;
		break;
	case IPV6_RECVERR:
		if (optlen < sizeof(int))
			goto e_inval;
		np->recverr = valbool;
		if (!val)
			skb_queue_purge(&sk->sk_error_queue);
		retv = 0;
		break;
	case IPV6_FLOWINFO_SEND:
		if (optlen < sizeof(int))
			goto e_inval;
		np->sndflow = valbool;
		retv = 0;
		break;
	case IPV6_FLOWLABEL_MGR:
		retv = ipv6_flowlabel_opt(sk, optval, optlen);
		break;
	case IPV6_IPSEC_POLICY:
	case IPV6_XFRM_POLICY:
		retv = -EPERM;
		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
			break;
		retv = xfrm_user_policy(sk, optname, optval, optlen);
		break;

	case IPV6_ADDR_PREFERENCES:
	    {
		unsigned int pref = 0;
		unsigned int prefmask = ~0;

		if (optlen < sizeof(int))
			goto e_inval;

		retv = -EINVAL;

		/* check PUBLIC/TMP/PUBTMP_DEFAULT conflicts */
		switch (val & (IPV6_PREFER_SRC_PUBLIC|
			       IPV6_PREFER_SRC_TMP|
			       IPV6_PREFER_SRC_PUBTMP_DEFAULT)) {
		case IPV6_PREFER_SRC_PUBLIC:
			pref |= IPV6_PREFER_SRC_PUBLIC;
			break;
		case IPV6_PREFER_SRC_TMP:
			pref |= IPV6_PREFER_SRC_TMP;
			break;
		case IPV6_PREFER_SRC_PUBTMP_DEFAULT:
			break;
		case 0:
			goto pref_skip_pubtmp;
		default:
			goto e_inval;
		}

		prefmask &= ~(IPV6_PREFER_SRC_PUBLIC|
			      IPV6_PREFER_SRC_TMP);
pref_skip_pubtmp:

		/* check HOME/COA conflicts */
		switch (val & (IPV6_PREFER_SRC_HOME|IPV6_PREFER_SRC_COA)) {
		case IPV6_PREFER_SRC_HOME:
			break;
		case IPV6_PREFER_SRC_COA:
			pref |= IPV6_PREFER_SRC_COA;
		case 0:
			goto pref_skip_coa;
		default:
			goto e_inval;
		}

		prefmask &= ~IPV6_PREFER_SRC_COA;
pref_skip_coa:

		/* check CGA/NONCGA conflicts */
		switch (val & (IPV6_PREFER_SRC_CGA|IPV6_PREFER_SRC_NONCGA)) {
		case IPV6_PREFER_SRC_CGA:
		case IPV6_PREFER_SRC_NONCGA:
		case 0:
			break;
		default:
			goto e_inval;
		}

		np->srcprefs = (np->srcprefs & prefmask) | pref;
		retv = 0;

		break;
	    }
	case IPV6_MINHOPCOUNT:
		if (optlen < sizeof(int))
			goto e_inval;
		if (val < 0 || val > 255)
			goto e_inval;
		np->min_hopcount = val;
		retv = 0;
		break;
	case IPV6_DONTFRAG:
		np->dontfrag = valbool;
		retv = 0;
		break;
	case IPV6_AUTOFLOWLABEL:
		np->autoflowlabel = valbool;
		retv = 0;
		break;
	}

	release_sock(sk);
	if (needs_rtnl)
		rtnl_unlock();

	return retv;

e_inval:
	release_sock(sk);
	if (needs_rtnl)
		rtnl_unlock();
	return -EINVAL;
}

int ipv6_setsockopt(struct sock *sk, int level, int optname,
		    char __user *optval, unsigned int optlen)
{
	int err;

	if (level == SOL_IP && sk->sk_type != SOCK_RAW)
		return udp_prot.setsockopt(sk, level, optname, optval, optlen);

	if (level != SOL_IPV6)
		return -ENOPROTOOPT;

	err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);
#ifdef CONFIG_NETFILTER
	/* we need to exclude all possible ENOPROTOOPTs except default case */
	if (err == -ENOPROTOOPT && optname != IPV6_IPSEC_POLICY &&
			optname != IPV6_XFRM_POLICY) {
		lock_sock(sk);
		err = nf_setsockopt(sk, PF_INET6, optname, optval,
				optlen);
		release_sock(sk);
	}
#endif
	return err;
}
EXPORT_SYMBOL(ipv6_setsockopt);

#ifdef CONFIG_COMPAT
int compat_ipv6_setsockopt(struct sock *sk, int level, int optname,
			   char __user *optval, unsigned int optlen)
{
	int err;

	if (level == SOL_IP && sk->sk_type != SOCK_RAW) {
		if (udp_prot.compat_setsockopt != NULL)
			return udp_prot.compat_setsockopt(sk, level, optname,
							  optval, optlen);
		return udp_prot.setsockopt(sk, level, optname, optval, optlen);
	}

	if (level != SOL_IPV6)
		return -ENOPROTOOPT;

	if (optname >= MCAST_JOIN_GROUP && optname <= MCAST_MSFILTER)
		return compat_mc_setsockopt(sk, level, optname, optval, optlen,
			ipv6_setsockopt);

	err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);
#ifdef CONFIG_NETFILTER
	/* we need to exclude all possible ENOPROTOOPTs except default case */
	if (err == -ENOPROTOOPT && optname != IPV6_IPSEC_POLICY &&
	    optname != IPV6_XFRM_POLICY) {
		lock_sock(sk);
		err = compat_nf_setsockopt(sk, PF_INET6, optname,
					   optval, optlen);
		release_sock(sk);
	}
#endif
	return err;
}
EXPORT_SYMBOL(compat_ipv6_setsockopt);
#endif

static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
				  int optname, char __user *optval, int len)
{
	struct ipv6_opt_hdr *hdr;

	if (!opt)
		return 0;

	switch (optname) {
	case IPV6_HOPOPTS:
		hdr = opt->hopopt;
		break;
	case IPV6_RTHDRDSTOPTS:
		hdr = opt->dst0opt;
		break;
	case IPV6_RTHDR:
		hdr = (struct ipv6_opt_hdr *)opt->srcrt;
		break;
	case IPV6_DSTOPTS:
		hdr = opt->dst1opt;
		break;
	default:
		return -EINVAL;	/* should not happen */
	}

	if (!hdr)
		return 0;

	len = min_t(unsigned int, len, ipv6_optlen(hdr));
	if (copy_to_user(optval, hdr, len))
		return -EFAULT;
	return len;
}

static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
		    char __user *optval, int __user *optlen, unsigned int flags)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	int len;
	int val;

	if (ip6_mroute_opt(optname))
		return ip6_mroute_getsockopt(sk, optname, optval, optlen);

	if (get_user(len, optlen))
		return -EFAULT;
	switch (optname) {
	case IPV6_ADDRFORM:
		if (sk->sk_protocol != IPPROTO_UDP &&
		    sk->sk_protocol != IPPROTO_UDPLITE &&
		    sk->sk_protocol != IPPROTO_TCP)
			return -ENOPROTOOPT;
		if (sk->sk_state != TCP_ESTABLISHED)
			return -ENOTCONN;
		val = sk->sk_family;
		break;
	case MCAST_MSFILTER:
	{
		struct group_filter gsf;
		int err;

		if (len < GROUP_FILTER_SIZE(0))
			return -EINVAL;
		if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0)))
			return -EFAULT;
		if (gsf.gf_group.ss_family != AF_INET6)
			return -EADDRNOTAVAIL;
		lock_sock(sk);
		err = ip6_mc_msfget(sk, &gsf,
			(struct group_filter __user *)optval, optlen);
		release_sock(sk);
		return err;
	}

	case IPV6_2292PKTOPTIONS:
	{
		struct msghdr msg;
		struct sk_buff *skb;

		if (sk->sk_type != SOCK_STREAM)
			return -ENOPROTOOPT;

		msg.msg_control = optval;
		msg.msg_controllen = len;
		msg.msg_flags = flags;

		lock_sock(sk);
		skb = np->pktoptions;
		if (skb)
			ip6_datagram_recv_ctl(sk, &msg, skb);
		release_sock(sk);
		if (!skb) {
			if (np->rxopt.bits.rxinfo) {
				struct in6_pktinfo src_info;
				src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
					np->sticky_pktinfo.ipi6_ifindex;
				src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr : np->sticky_pktinfo.ipi6_addr;
				put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
			}
			if (np->rxopt.bits.rxhlim) {
				int hlim = np->mcast_hops;
				put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
			}
			if (np->rxopt.bits.rxtclass) {
				int tclass = (int)ip6_tclass(np->rcv_flowinfo);

				put_cmsg(&msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
			}
			if (np->rxopt.bits.rxoinfo) {
				struct in6_pktinfo src_info;
				src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
					np->sticky_pktinfo.ipi6_ifindex;
				src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr :
								     np->sticky_pktinfo.ipi6_addr;
				put_cmsg(&msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
			}
			if (np->rxopt.bits.rxohlim) {
				int hlim = np->mcast_hops;
				put_cmsg(&msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
			}
			if (np->rxopt.bits.rxflow) {
				__be32 flowinfo = np->rcv_flowinfo;

				put_cmsg(&msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
			}
		}
		len -= msg.msg_controllen;
		return put_user(len, optlen);
	}
	case IPV6_MTU:
	{
		struct dst_entry *dst;

		val = 0;
		rcu_read_lock();
		dst = __sk_dst_get(sk);
		if (dst)
			val = dst_mtu(dst);
		rcu_read_unlock();
		if (!val)
			return -ENOTCONN;
		break;
	}

	case IPV6_V6ONLY:
		val = sk->sk_ipv6only;
		break;

	case IPV6_RECVPKTINFO:
		val = np->rxopt.bits.rxinfo;
		break;

	case IPV6_2292PKTINFO:
		val = np->rxopt.bits.rxoinfo;
		break;

	case IPV6_RECVHOPLIMIT:
		val = np->rxopt.bits.rxhlim;
		break;

	case IPV6_2292HOPLIMIT:
		val = np->rxopt.bits.rxohlim;
		break;

	case IPV6_RECVRTHDR:
		val = np->rxopt.bits.srcrt;
		break;

	case IPV6_2292RTHDR:
		val = np->rxopt.bits.osrcrt;
		break;

	case IPV6_HOPOPTS:
	case IPV6_RTHDRDSTOPTS:
	case IPV6_RTHDR:
	case IPV6_DSTOPTS:
	{
		struct ipv6_txoptions *opt;

		lock_sock(sk);
		opt = rcu_dereference_protected(np->opt,
						lockdep_sock_is_held(sk));
		len = ipv6_getsockopt_sticky(sk, opt, optname, optval, len);
		release_sock(sk);
		/* check if ipv6_getsockopt_sticky() returns err code */
		if (len < 0)
			return len;
		return put_user(len, optlen);
	}

	case IPV6_RECVHOPOPTS:
		val = np->rxopt.bits.hopopts;
		break;

	case IPV6_2292HOPOPTS:
		val = np->rxopt.bits.ohopopts;
		break;

	case IPV6_RECVDSTOPTS:
		val = np->rxopt.bits.dstopts;
		break;

	case IPV6_2292DSTOPTS:
		val = np->rxopt.bits.odstopts;
		break;

	case IPV6_TCLASS:
		val = np->tclass;
		break;

	case IPV6_RECVTCLASS:
		val = np->rxopt.bits.rxtclass;
		break;

	case IPV6_FLOWINFO:
		val = np->rxopt.bits.rxflow;
		break;

	case IPV6_RECVPATHMTU:
		val = np->rxopt.bits.rxpmtu;
		break;

	case IPV6_PATHMTU:
	{
		struct dst_entry *dst;
		struct ip6_mtuinfo mtuinfo;

		if (len < sizeof(mtuinfo))
			return -EINVAL;

		len = sizeof(mtuinfo);
		memset(&mtuinfo, 0, sizeof(mtuinfo));

		rcu_read_lock();
		dst = __sk_dst_get(sk);
		if (dst)
			mtuinfo.ip6m_mtu = dst_mtu(dst);
		rcu_read_unlock();
		if (!mtuinfo.ip6m_mtu)
			return -ENOTCONN;

		if (put_user(len, optlen))
			return -EFAULT;
		if (copy_to_user(optval, &mtuinfo, len))
			return -EFAULT;

		return 0;
	}

	case IPV6_TRANSPARENT:
		val = inet_sk(sk)->transparent;
		break;

	case IPV6_RECVORIGDSTADDR:
		val = np->rxopt.bits.rxorigdstaddr;
		break;

	case IPV6_UNICAST_HOPS:
	case IPV6_MULTICAST_HOPS:
	{
		struct dst_entry *dst;

		if (optname == IPV6_UNICAST_HOPS)
			val = np->hop_limit;
		else
			val = np->mcast_hops;

		if (val < 0) {
			rcu_read_lock();
			dst = __sk_dst_get(sk);
			if (dst)
				val = ip6_dst_hoplimit(dst);
			rcu_read_unlock();
		}

		if (val < 0)
			val = sock_net(sk)->ipv6.devconf_all->hop_limit;
		break;
	}

	case IPV6_MULTICAST_LOOP:
		val = np->mc_loop;
		break;

	case IPV6_MULTICAST_IF:
		val = np->mcast_oif;
		break;

	case IPV6_UNICAST_IF:
		val = (__force int)htonl((__u32) np->ucast_oif);
		break;

	case IPV6_MTU_DISCOVER:
		val = np->pmtudisc;
		break;

	case IPV6_RECVERR:
		val = np->recverr;
		break;

	case IPV6_FLOWINFO_SEND:
		val = np->sndflow;
		break;

	case IPV6_FLOWLABEL_MGR:
	{
		struct in6_flowlabel_req freq;
		int flags;

		if (len < sizeof(freq))
			return -EINVAL;

		if (copy_from_user(&freq, optval, sizeof(freq)))
			return -EFAULT;

		if (freq.flr_action != IPV6_FL_A_GET)
			return -EINVAL;

		len = sizeof(freq);
		flags = freq.flr_flags;

		memset(&freq, 0, sizeof(freq));

		val = ipv6_flowlabel_opt_get(sk, &freq, flags);
		if (val < 0)
			return val;

		if (put_user(len, optlen))
			return -EFAULT;
		if (copy_to_user(optval, &freq, len))
			return -EFAULT;

		return 0;
	}

	case IPV6_ADDR_PREFERENCES:
		val = 0;

		if (np->srcprefs & IPV6_PREFER_SRC_TMP)
			val |= IPV6_PREFER_SRC_TMP;
		else if (np->srcprefs & IPV6_PREFER_SRC_PUBLIC)
			val |= IPV6_PREFER_SRC_PUBLIC;
		else {
			/* XXX: should we return system default? */
			val |= IPV6_PREFER_SRC_PUBTMP_DEFAULT;
		}

		if (np->srcprefs & IPV6_PREFER_SRC_COA)
			val |= IPV6_PREFER_SRC_COA;
		else
			val |= IPV6_PREFER_SRC_HOME;
		break;

	case IPV6_MINHOPCOUNT:
		val = np->min_hopcount;
		break;

	case IPV6_DONTFRAG:
		val = np->dontfrag;
		break;

	case IPV6_AUTOFLOWLABEL:
		val = np->autoflowlabel;
		break;

	default:
		return -ENOPROTOOPT;
	}
	len = min_t(unsigned int, sizeof(int), len);
	if (put_user(len, optlen))
		return -EFAULT;
	if (copy_to_user(optval, &val, len))
		return -EFAULT;
	return 0;
}

int ipv6_getsockopt(struct sock *sk, int level, int optname,
		    char __user *optval, int __user *optlen)
{
	int err;

	if (level == SOL_IP && sk->sk_type != SOCK_RAW)
		return udp_prot.getsockopt(sk, level, optname, optval, optlen);

	if (level != SOL_IPV6)
		return -ENOPROTOOPT;

	err = do_ipv6_getsockopt(sk, level, optname, optval, optlen, 0);
#ifdef CONFIG_NETFILTER
	/* we need to exclude all possible ENOPROTOOPTs except default case */
	if (err == -ENOPROTOOPT && optname != IPV6_2292PKTOPTIONS) {
		int len;

		if (get_user(len, optlen))
			return -EFAULT;

		lock_sock(sk);
		err = nf_getsockopt(sk, PF_INET6, optname, optval,
				&len);
		release_sock(sk);
		if (err >= 0)
			err = put_user(len, optlen);
	}
#endif
	return err;
}
EXPORT_SYMBOL(ipv6_getsockopt);

#ifdef CONFIG_COMPAT
int compat_ipv6_getsockopt(struct sock *sk, int level, int optname,
			   char __user *optval, int __user *optlen)
{
	int err;

	if (level == SOL_IP && sk->sk_type != SOCK_RAW) {
		if (udp_prot.compat_getsockopt != NULL)
			return udp_prot.compat_getsockopt(sk, level, optname,
							  optval, optlen);
		return udp_prot.getsockopt(sk, level, optname, optval, optlen);
	}

	if (level != SOL_IPV6)
		return -ENOPROTOOPT;

	if (optname == MCAST_MSFILTER)
		return compat_mc_getsockopt(sk, level, optname, optval, optlen,
			ipv6_getsockopt);

	err = do_ipv6_getsockopt(sk, level, optname, optval, optlen,
				 MSG_CMSG_COMPAT);
#ifdef CONFIG_NETFILTER
	/* we need to exclude all possible ENOPROTOOPTs except default case */
	if (err == -ENOPROTOOPT && optname != IPV6_2292PKTOPTIONS) {
		int len;

		if (get_user(len, optlen))
			return -EFAULT;

		lock_sock(sk);
		err = compat_nf_getsockopt(sk, PF_INET6,
					   optname, optval, &len);
		release_sock(sk);
		if (err >= 0)
			err = put_user(len, optlen);
	}
#endif
	return err;
}
EXPORT_SYMBOL(compat_ipv6_getsockopt);
#endif