xref: /linux/net/ipv4/ip_sockglue.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
1 /*
2  * INET		An implementation of the TCP/IP protocol suite for the LINUX
3  *		operating system.  INET is implemented using the  BSD Socket
4  *		interface as the means of communication with the user level.
5  *
6  *		The IP to API glue.
7  *
8  * Authors:	see ip.c
9  *
10  * Fixes:
11  *		Many		:	Split from ip.c , see ip.c for history.
12  *		Martin Mares	:	TOS setting fixed.
13  *		Alan Cox	:	Fixed a couple of oopses in Martin's
14  *					TOS tweaks.
15  *		Mike McLagan	:	Routing by source
16  */
17 
18 #include <linux/module.h>
19 #include <linux/types.h>
20 #include <linux/mm.h>
21 #include <linux/skbuff.h>
22 #include <linux/ip.h>
23 #include <linux/icmp.h>
24 #include <linux/inetdevice.h>
25 #include <linux/netdevice.h>
26 #include <linux/slab.h>
27 #include <net/sock.h>
28 #include <net/ip.h>
29 #include <net/icmp.h>
30 #include <net/tcp_states.h>
31 #include <linux/udp.h>
32 #include <linux/igmp.h>
33 #include <linux/netfilter.h>
34 #include <linux/route.h>
35 #include <linux/mroute.h>
36 #include <net/route.h>
37 #include <net/xfrm.h>
38 #include <net/compat.h>
39 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
40 #include <net/transp_v6.h>
41 #endif
42 
43 #include <linux/errqueue.h>
44 #include <asm/uaccess.h>
45 
46 #define IP_CMSG_PKTINFO		1
47 #define IP_CMSG_TTL		2
48 #define IP_CMSG_TOS		4
49 #define IP_CMSG_RECVOPTS	8
50 #define IP_CMSG_RETOPTS		16
51 #define IP_CMSG_PASSSEC		32
52 #define IP_CMSG_ORIGDSTADDR     64
53 
54 /*
55  *	SOL_IP control messages.
56  */
57 
58 static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
59 {
60 	struct in_pktinfo info;
61 	struct rtable *rt = skb_rtable(skb);
62 
63 	info.ipi_addr.s_addr = ip_hdr(skb)->daddr;
64 	if (rt) {
65 		info.ipi_ifindex = rt->rt_iif;
66 		info.ipi_spec_dst.s_addr = rt->rt_spec_dst;
67 	} else {
68 		info.ipi_ifindex = 0;
69 		info.ipi_spec_dst.s_addr = 0;
70 	}
71 
72 	put_cmsg(msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
73 }
74 
75 static void ip_cmsg_recv_ttl(struct msghdr *msg, struct sk_buff *skb)
76 {
77 	int ttl = ip_hdr(skb)->ttl;
78 	put_cmsg(msg, SOL_IP, IP_TTL, sizeof(int), &ttl);
79 }
80 
81 static void ip_cmsg_recv_tos(struct msghdr *msg, struct sk_buff *skb)
82 {
83 	put_cmsg(msg, SOL_IP, IP_TOS, 1, &ip_hdr(skb)->tos);
84 }
85 
86 static void ip_cmsg_recv_opts(struct msghdr *msg, struct sk_buff *skb)
87 {
88 	if (IPCB(skb)->opt.optlen == 0)
89 		return;
90 
91 	put_cmsg(msg, SOL_IP, IP_RECVOPTS, IPCB(skb)->opt.optlen,
92 		 ip_hdr(skb) + 1);
93 }
94 
95 
96 static void ip_cmsg_recv_retopts(struct msghdr *msg, struct sk_buff *skb)
97 {
98 	unsigned char optbuf[sizeof(struct ip_options) + 40];
99 	struct ip_options * opt = (struct ip_options *)optbuf;
100 
101 	if (IPCB(skb)->opt.optlen == 0)
102 		return;
103 
104 	if (ip_options_echo(opt, skb)) {
105 		msg->msg_flags |= MSG_CTRUNC;
106 		return;
107 	}
108 	ip_options_undo(opt);
109 
110 	put_cmsg(msg, SOL_IP, IP_RETOPTS, opt->optlen, opt->__data);
111 }
112 
113 static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
114 {
115 	char *secdata;
116 	u32 seclen, secid;
117 	int err;
118 
119 	err = security_socket_getpeersec_dgram(NULL, skb, &secid);
120 	if (err)
121 		return;
122 
123 	err = security_secid_to_secctx(secid, &secdata, &seclen);
124 	if (err)
125 		return;
126 
127 	put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
128 	security_release_secctx(secdata, seclen);
129 }
130 
131 static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb)
132 {
133 	struct sockaddr_in sin;
134 	struct iphdr *iph = ip_hdr(skb);
135 	__be16 *ports = (__be16 *)skb_transport_header(skb);
136 
137 	if (skb_transport_offset(skb) + 4 > skb->len)
138 		return;
139 
140 	/* All current transport protocols have the port numbers in the
141 	 * first four bytes of the transport header and this function is
142 	 * written with this assumption in mind.
143 	 */
144 
145 	sin.sin_family = AF_INET;
146 	sin.sin_addr.s_addr = iph->daddr;
147 	sin.sin_port = ports[1];
148 	memset(sin.sin_zero, 0, sizeof(sin.sin_zero));
149 
150 	put_cmsg(msg, SOL_IP, IP_ORIGDSTADDR, sizeof(sin), &sin);
151 }
152 
153 void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
154 {
155 	struct inet_sock *inet = inet_sk(skb->sk);
156 	unsigned flags = inet->cmsg_flags;
157 
158 	/* Ordered by supposed usage frequency */
159 	if (flags & 1)
160 		ip_cmsg_recv_pktinfo(msg, skb);
161 	if ((flags >>= 1) == 0)
162 		return;
163 
164 	if (flags & 1)
165 		ip_cmsg_recv_ttl(msg, skb);
166 	if ((flags >>= 1) == 0)
167 		return;
168 
169 	if (flags & 1)
170 		ip_cmsg_recv_tos(msg, skb);
171 	if ((flags >>= 1) == 0)
172 		return;
173 
174 	if (flags & 1)
175 		ip_cmsg_recv_opts(msg, skb);
176 	if ((flags >>= 1) == 0)
177 		return;
178 
179 	if (flags & 1)
180 		ip_cmsg_recv_retopts(msg, skb);
181 	if ((flags >>= 1) == 0)
182 		return;
183 
184 	if (flags & 1)
185 		ip_cmsg_recv_security(msg, skb);
186 
187 	if ((flags >>= 1) == 0)
188 		return;
189 	if (flags & 1)
190 		ip_cmsg_recv_dstaddr(msg, skb);
191 
192 }
193 EXPORT_SYMBOL(ip_cmsg_recv);
194 
195 int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc)
196 {
197 	int err;
198 	struct cmsghdr *cmsg;
199 
200 	for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
201 		if (!CMSG_OK(msg, cmsg))
202 			return -EINVAL;
203 		if (cmsg->cmsg_level != SOL_IP)
204 			continue;
205 		switch (cmsg->cmsg_type) {
206 		case IP_RETOPTS:
207 			err = cmsg->cmsg_len - CMSG_ALIGN(sizeof(struct cmsghdr));
208 			err = ip_options_get(net, &ipc->opt, CMSG_DATA(cmsg),
209 					     err < 40 ? err : 40);
210 			if (err)
211 				return err;
212 			break;
213 		case IP_PKTINFO:
214 		{
215 			struct in_pktinfo *info;
216 			if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo)))
217 				return -EINVAL;
218 			info = (struct in_pktinfo *)CMSG_DATA(cmsg);
219 			ipc->oif = info->ipi_ifindex;
220 			ipc->addr = info->ipi_spec_dst.s_addr;
221 			break;
222 		}
223 		default:
224 			return -EINVAL;
225 		}
226 	}
227 	return 0;
228 }
229 
230 
231 /* Special input handler for packets caught by router alert option.
232    They are selected only by protocol field, and then processed likely
233    local ones; but only if someone wants them! Otherwise, router
234    not running rsvpd will kill RSVP.
235 
236    It is user level problem, what it will make with them.
237    I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
238    but receiver should be enough clever f.e. to forward mtrace requests,
239    sent to multicast group to reach destination designated router.
240  */
241 struct ip_ra_chain *ip_ra_chain;
242 static DEFINE_SPINLOCK(ip_ra_lock);
243 
244 
245 static void ip_ra_destroy_rcu(struct rcu_head *head)
246 {
247 	struct ip_ra_chain *ra = container_of(head, struct ip_ra_chain, rcu);
248 
249 	sock_put(ra->saved_sk);
250 	kfree(ra);
251 }
252 
253 int ip_ra_control(struct sock *sk, unsigned char on,
254 		  void (*destructor)(struct sock *))
255 {
256 	struct ip_ra_chain *ra, *new_ra, **rap;
257 
258 	if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num == IPPROTO_RAW)
259 		return -EINVAL;
260 
261 	new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
262 
263 	spin_lock_bh(&ip_ra_lock);
264 	for (rap = &ip_ra_chain; (ra = *rap) != NULL; rap = &ra->next) {
265 		if (ra->sk == sk) {
266 			if (on) {
267 				spin_unlock_bh(&ip_ra_lock);
268 				kfree(new_ra);
269 				return -EADDRINUSE;
270 			}
271 			/* dont let ip_call_ra_chain() use sk again */
272 			ra->sk = NULL;
273 			rcu_assign_pointer(*rap, ra->next);
274 			spin_unlock_bh(&ip_ra_lock);
275 
276 			if (ra->destructor)
277 				ra->destructor(sk);
278 			/*
279 			 * Delay sock_put(sk) and kfree(ra) after one rcu grace
280 			 * period. This guarantee ip_call_ra_chain() dont need
281 			 * to mess with socket refcounts.
282 			 */
283 			ra->saved_sk = sk;
284 			call_rcu(&ra->rcu, ip_ra_destroy_rcu);
285 			return 0;
286 		}
287 	}
288 	if (new_ra == NULL) {
289 		spin_unlock_bh(&ip_ra_lock);
290 		return -ENOBUFS;
291 	}
292 	new_ra->sk = sk;
293 	new_ra->destructor = destructor;
294 
295 	new_ra->next = ra;
296 	rcu_assign_pointer(*rap, new_ra);
297 	sock_hold(sk);
298 	spin_unlock_bh(&ip_ra_lock);
299 
300 	return 0;
301 }
302 
303 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
304 		   __be16 port, u32 info, u8 *payload)
305 {
306 	struct sock_exterr_skb *serr;
307 
308 	skb = skb_clone(skb, GFP_ATOMIC);
309 	if (!skb)
310 		return;
311 
312 	serr = SKB_EXT_ERR(skb);
313 	serr->ee.ee_errno = err;
314 	serr->ee.ee_origin = SO_EE_ORIGIN_ICMP;
315 	serr->ee.ee_type = icmp_hdr(skb)->type;
316 	serr->ee.ee_code = icmp_hdr(skb)->code;
317 	serr->ee.ee_pad = 0;
318 	serr->ee.ee_info = info;
319 	serr->ee.ee_data = 0;
320 	serr->addr_offset = (u8 *)&(((struct iphdr *)(icmp_hdr(skb) + 1))->daddr) -
321 				   skb_network_header(skb);
322 	serr->port = port;
323 
324 	if (skb_pull(skb, payload - skb->data) != NULL) {
325 		skb_reset_transport_header(skb);
326 		if (sock_queue_err_skb(sk, skb) == 0)
327 			return;
328 	}
329 	kfree_skb(skb);
330 }
331 
332 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info)
333 {
334 	struct inet_sock *inet = inet_sk(sk);
335 	struct sock_exterr_skb *serr;
336 	struct iphdr *iph;
337 	struct sk_buff *skb;
338 
339 	if (!inet->recverr)
340 		return;
341 
342 	skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC);
343 	if (!skb)
344 		return;
345 
346 	skb_put(skb, sizeof(struct iphdr));
347 	skb_reset_network_header(skb);
348 	iph = ip_hdr(skb);
349 	iph->daddr = daddr;
350 
351 	serr = SKB_EXT_ERR(skb);
352 	serr->ee.ee_errno = err;
353 	serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
354 	serr->ee.ee_type = 0;
355 	serr->ee.ee_code = 0;
356 	serr->ee.ee_pad = 0;
357 	serr->ee.ee_info = info;
358 	serr->ee.ee_data = 0;
359 	serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
360 	serr->port = port;
361 
362 	__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
363 	skb_reset_transport_header(skb);
364 
365 	if (sock_queue_err_skb(sk, skb))
366 		kfree_skb(skb);
367 }
368 
369 /*
370  *	Handle MSG_ERRQUEUE
371  */
372 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len)
373 {
374 	struct sock_exterr_skb *serr;
375 	struct sk_buff *skb, *skb2;
376 	struct sockaddr_in *sin;
377 	struct {
378 		struct sock_extended_err ee;
379 		struct sockaddr_in	 offender;
380 	} errhdr;
381 	int err;
382 	int copied;
383 
384 	err = -EAGAIN;
385 	skb = skb_dequeue(&sk->sk_error_queue);
386 	if (skb == NULL)
387 		goto out;
388 
389 	copied = skb->len;
390 	if (copied > len) {
391 		msg->msg_flags |= MSG_TRUNC;
392 		copied = len;
393 	}
394 	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
395 	if (err)
396 		goto out_free_skb;
397 
398 	sock_recv_timestamp(msg, sk, skb);
399 
400 	serr = SKB_EXT_ERR(skb);
401 
402 	sin = (struct sockaddr_in *)msg->msg_name;
403 	if (sin) {
404 		sin->sin_family = AF_INET;
405 		sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) +
406 						   serr->addr_offset);
407 		sin->sin_port = serr->port;
408 		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
409 	}
410 
411 	memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
412 	sin = &errhdr.offender;
413 	sin->sin_family = AF_UNSPEC;
414 	if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP) {
415 		struct inet_sock *inet = inet_sk(sk);
416 
417 		sin->sin_family = AF_INET;
418 		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
419 		sin->sin_port = 0;
420 		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
421 		if (inet->cmsg_flags)
422 			ip_cmsg_recv(msg, skb);
423 	}
424 
425 	put_cmsg(msg, SOL_IP, IP_RECVERR, sizeof(errhdr), &errhdr);
426 
427 	/* Now we could try to dump offended packet options */
428 
429 	msg->msg_flags |= MSG_ERRQUEUE;
430 	err = copied;
431 
432 	/* Reset and regenerate socket error */
433 	spin_lock_bh(&sk->sk_error_queue.lock);
434 	sk->sk_err = 0;
435 	skb2 = skb_peek(&sk->sk_error_queue);
436 	if (skb2 != NULL) {
437 		sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
438 		spin_unlock_bh(&sk->sk_error_queue.lock);
439 		sk->sk_error_report(sk);
440 	} else
441 		spin_unlock_bh(&sk->sk_error_queue.lock);
442 
443 out_free_skb:
444 	kfree_skb(skb);
445 out:
446 	return err;
447 }
448 
449 
450 /*
451  *	Socket option code for IP. This is the end of the line after any
452  *	TCP,UDP etc options on an IP socket.
453  */
454 
455 static int do_ip_setsockopt(struct sock *sk, int level,
456 			    int optname, char __user *optval, unsigned int optlen)
457 {
458 	struct inet_sock *inet = inet_sk(sk);
459 	int val = 0, err;
460 
461 	if (((1<<optname) & ((1<<IP_PKTINFO) | (1<<IP_RECVTTL) |
462 			     (1<<IP_RECVOPTS) | (1<<IP_RECVTOS) |
463 			     (1<<IP_RETOPTS) | (1<<IP_TOS) |
464 			     (1<<IP_TTL) | (1<<IP_HDRINCL) |
465 			     (1<<IP_MTU_DISCOVER) | (1<<IP_RECVERR) |
466 			     (1<<IP_ROUTER_ALERT) | (1<<IP_FREEBIND) |
467 			     (1<<IP_PASSSEC) | (1<<IP_TRANSPARENT) |
468 			     (1<<IP_MINTTL) | (1<<IP_NODEFRAG))) ||
469 	    optname == IP_MULTICAST_TTL ||
470 	    optname == IP_MULTICAST_ALL ||
471 	    optname == IP_MULTICAST_LOOP ||
472 	    optname == IP_RECVORIGDSTADDR) {
473 		if (optlen >= sizeof(int)) {
474 			if (get_user(val, (int __user *) optval))
475 				return -EFAULT;
476 		} else if (optlen >= sizeof(char)) {
477 			unsigned char ucval;
478 
479 			if (get_user(ucval, (unsigned char __user *) optval))
480 				return -EFAULT;
481 			val = (int) ucval;
482 		}
483 	}
484 
485 	/* If optlen==0, it is equivalent to val == 0 */
486 
487 	if (ip_mroute_opt(optname))
488 		return ip_mroute_setsockopt(sk, optname, optval, optlen);
489 
490 	err = 0;
491 	lock_sock(sk);
492 
493 	switch (optname) {
494 	case IP_OPTIONS:
495 	{
496 		struct ip_options *opt = NULL;
497 		if (optlen > 40)
498 			goto e_inval;
499 		err = ip_options_get_from_user(sock_net(sk), &opt,
500 					       optval, optlen);
501 		if (err)
502 			break;
503 		if (inet->is_icsk) {
504 			struct inet_connection_sock *icsk = inet_csk(sk);
505 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
506 			if (sk->sk_family == PF_INET ||
507 			    (!((1 << sk->sk_state) &
508 			       (TCPF_LISTEN | TCPF_CLOSE)) &&
509 			     inet->inet_daddr != LOOPBACK4_IPV6)) {
510 #endif
511 				if (inet->opt)
512 					icsk->icsk_ext_hdr_len -= inet->opt->optlen;
513 				if (opt)
514 					icsk->icsk_ext_hdr_len += opt->optlen;
515 				icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
516 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
517 			}
518 #endif
519 		}
520 		opt = xchg(&inet->opt, opt);
521 		kfree(opt);
522 		break;
523 	}
524 	case IP_PKTINFO:
525 		if (val)
526 			inet->cmsg_flags |= IP_CMSG_PKTINFO;
527 		else
528 			inet->cmsg_flags &= ~IP_CMSG_PKTINFO;
529 		break;
530 	case IP_RECVTTL:
531 		if (val)
532 			inet->cmsg_flags |=  IP_CMSG_TTL;
533 		else
534 			inet->cmsg_flags &= ~IP_CMSG_TTL;
535 		break;
536 	case IP_RECVTOS:
537 		if (val)
538 			inet->cmsg_flags |=  IP_CMSG_TOS;
539 		else
540 			inet->cmsg_flags &= ~IP_CMSG_TOS;
541 		break;
542 	case IP_RECVOPTS:
543 		if (val)
544 			inet->cmsg_flags |=  IP_CMSG_RECVOPTS;
545 		else
546 			inet->cmsg_flags &= ~IP_CMSG_RECVOPTS;
547 		break;
548 	case IP_RETOPTS:
549 		if (val)
550 			inet->cmsg_flags |= IP_CMSG_RETOPTS;
551 		else
552 			inet->cmsg_flags &= ~IP_CMSG_RETOPTS;
553 		break;
554 	case IP_PASSSEC:
555 		if (val)
556 			inet->cmsg_flags |= IP_CMSG_PASSSEC;
557 		else
558 			inet->cmsg_flags &= ~IP_CMSG_PASSSEC;
559 		break;
560 	case IP_RECVORIGDSTADDR:
561 		if (val)
562 			inet->cmsg_flags |= IP_CMSG_ORIGDSTADDR;
563 		else
564 			inet->cmsg_flags &= ~IP_CMSG_ORIGDSTADDR;
565 		break;
566 	case IP_TOS:	/* This sets both TOS and Precedence */
567 		if (sk->sk_type == SOCK_STREAM) {
568 			val &= ~3;
569 			val |= inet->tos & 3;
570 		}
571 		if (inet->tos != val) {
572 			inet->tos = val;
573 			sk->sk_priority = rt_tos2priority(val);
574 			sk_dst_reset(sk);
575 		}
576 		break;
577 	case IP_TTL:
578 		if (optlen < 1)
579 			goto e_inval;
580 		if (val != -1 && (val < 0 || val > 255))
581 			goto e_inval;
582 		inet->uc_ttl = val;
583 		break;
584 	case IP_HDRINCL:
585 		if (sk->sk_type != SOCK_RAW) {
586 			err = -ENOPROTOOPT;
587 			break;
588 		}
589 		inet->hdrincl = val ? 1 : 0;
590 		break;
591 	case IP_NODEFRAG:
592 		if (sk->sk_type != SOCK_RAW) {
593 			err = -ENOPROTOOPT;
594 			break;
595 		}
596 		inet->nodefrag = val ? 1 : 0;
597 		break;
598 	case IP_MTU_DISCOVER:
599 		if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_PROBE)
600 			goto e_inval;
601 		inet->pmtudisc = val;
602 		break;
603 	case IP_RECVERR:
604 		inet->recverr = !!val;
605 		if (!val)
606 			skb_queue_purge(&sk->sk_error_queue);
607 		break;
608 	case IP_MULTICAST_TTL:
609 		if (sk->sk_type == SOCK_STREAM)
610 			goto e_inval;
611 		if (optlen < 1)
612 			goto e_inval;
613 		if (val == -1)
614 			val = 1;
615 		if (val < 0 || val > 255)
616 			goto e_inval;
617 		inet->mc_ttl = val;
618 		break;
619 	case IP_MULTICAST_LOOP:
620 		if (optlen < 1)
621 			goto e_inval;
622 		inet->mc_loop = !!val;
623 		break;
624 	case IP_MULTICAST_IF:
625 	{
626 		struct ip_mreqn mreq;
627 		struct net_device *dev = NULL;
628 
629 		if (sk->sk_type == SOCK_STREAM)
630 			goto e_inval;
631 		/*
632 		 *	Check the arguments are allowable
633 		 */
634 
635 		if (optlen < sizeof(struct in_addr))
636 			goto e_inval;
637 
638 		err = -EFAULT;
639 		if (optlen >= sizeof(struct ip_mreqn)) {
640 			if (copy_from_user(&mreq, optval, sizeof(mreq)))
641 				break;
642 		} else {
643 			memset(&mreq, 0, sizeof(mreq));
644 			if (optlen >= sizeof(struct in_addr) &&
645 			    copy_from_user(&mreq.imr_address, optval,
646 					   sizeof(struct in_addr)))
647 				break;
648 		}
649 
650 		if (!mreq.imr_ifindex) {
651 			if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) {
652 				inet->mc_index = 0;
653 				inet->mc_addr  = 0;
654 				err = 0;
655 				break;
656 			}
657 			dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr);
658 			if (dev)
659 				mreq.imr_ifindex = dev->ifindex;
660 		} else
661 			dev = dev_get_by_index(sock_net(sk), mreq.imr_ifindex);
662 
663 
664 		err = -EADDRNOTAVAIL;
665 		if (!dev)
666 			break;
667 		dev_put(dev);
668 
669 		err = -EINVAL;
670 		if (sk->sk_bound_dev_if &&
671 		    mreq.imr_ifindex != sk->sk_bound_dev_if)
672 			break;
673 
674 		inet->mc_index = mreq.imr_ifindex;
675 		inet->mc_addr  = mreq.imr_address.s_addr;
676 		err = 0;
677 		break;
678 	}
679 
680 	case IP_ADD_MEMBERSHIP:
681 	case IP_DROP_MEMBERSHIP:
682 	{
683 		struct ip_mreqn mreq;
684 
685 		err = -EPROTO;
686 		if (inet_sk(sk)->is_icsk)
687 			break;
688 
689 		if (optlen < sizeof(struct ip_mreq))
690 			goto e_inval;
691 		err = -EFAULT;
692 		if (optlen >= sizeof(struct ip_mreqn)) {
693 			if (copy_from_user(&mreq, optval, sizeof(mreq)))
694 				break;
695 		} else {
696 			memset(&mreq, 0, sizeof(mreq));
697 			if (copy_from_user(&mreq, optval, sizeof(struct ip_mreq)))
698 				break;
699 		}
700 
701 		if (optname == IP_ADD_MEMBERSHIP)
702 			err = ip_mc_join_group(sk, &mreq);
703 		else
704 			err = ip_mc_leave_group(sk, &mreq);
705 		break;
706 	}
707 	case IP_MSFILTER:
708 	{
709 		struct ip_msfilter *msf;
710 
711 		if (optlen < IP_MSFILTER_SIZE(0))
712 			goto e_inval;
713 		if (optlen > sysctl_optmem_max) {
714 			err = -ENOBUFS;
715 			break;
716 		}
717 		msf = kmalloc(optlen, GFP_KERNEL);
718 		if (!msf) {
719 			err = -ENOBUFS;
720 			break;
721 		}
722 		err = -EFAULT;
723 		if (copy_from_user(msf, optval, optlen)) {
724 			kfree(msf);
725 			break;
726 		}
727 		/* numsrc >= (1G-4) overflow in 32 bits */
728 		if (msf->imsf_numsrc >= 0x3ffffffcU ||
729 		    msf->imsf_numsrc > sysctl_igmp_max_msf) {
730 			kfree(msf);
731 			err = -ENOBUFS;
732 			break;
733 		}
734 		if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {
735 			kfree(msf);
736 			err = -EINVAL;
737 			break;
738 		}
739 		err = ip_mc_msfilter(sk, msf, 0);
740 		kfree(msf);
741 		break;
742 	}
743 	case IP_BLOCK_SOURCE:
744 	case IP_UNBLOCK_SOURCE:
745 	case IP_ADD_SOURCE_MEMBERSHIP:
746 	case IP_DROP_SOURCE_MEMBERSHIP:
747 	{
748 		struct ip_mreq_source mreqs;
749 		int omode, add;
750 
751 		if (optlen != sizeof(struct ip_mreq_source))
752 			goto e_inval;
753 		if (copy_from_user(&mreqs, optval, sizeof(mreqs))) {
754 			err = -EFAULT;
755 			break;
756 		}
757 		if (optname == IP_BLOCK_SOURCE) {
758 			omode = MCAST_EXCLUDE;
759 			add = 1;
760 		} else if (optname == IP_UNBLOCK_SOURCE) {
761 			omode = MCAST_EXCLUDE;
762 			add = 0;
763 		} else if (optname == IP_ADD_SOURCE_MEMBERSHIP) {
764 			struct ip_mreqn mreq;
765 
766 			mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
767 			mreq.imr_address.s_addr = mreqs.imr_interface;
768 			mreq.imr_ifindex = 0;
769 			err = ip_mc_join_group(sk, &mreq);
770 			if (err && err != -EADDRINUSE)
771 				break;
772 			omode = MCAST_INCLUDE;
773 			add = 1;
774 		} else /* IP_DROP_SOURCE_MEMBERSHIP */ {
775 			omode = MCAST_INCLUDE;
776 			add = 0;
777 		}
778 		err = ip_mc_source(add, omode, sk, &mreqs, 0);
779 		break;
780 	}
781 	case MCAST_JOIN_GROUP:
782 	case MCAST_LEAVE_GROUP:
783 	{
784 		struct group_req greq;
785 		struct sockaddr_in *psin;
786 		struct ip_mreqn mreq;
787 
788 		if (optlen < sizeof(struct group_req))
789 			goto e_inval;
790 		err = -EFAULT;
791 		if (copy_from_user(&greq, optval, sizeof(greq)))
792 			break;
793 		psin = (struct sockaddr_in *)&greq.gr_group;
794 		if (psin->sin_family != AF_INET)
795 			goto e_inval;
796 		memset(&mreq, 0, sizeof(mreq));
797 		mreq.imr_multiaddr = psin->sin_addr;
798 		mreq.imr_ifindex = greq.gr_interface;
799 
800 		if (optname == MCAST_JOIN_GROUP)
801 			err = ip_mc_join_group(sk, &mreq);
802 		else
803 			err = ip_mc_leave_group(sk, &mreq);
804 		break;
805 	}
806 	case MCAST_JOIN_SOURCE_GROUP:
807 	case MCAST_LEAVE_SOURCE_GROUP:
808 	case MCAST_BLOCK_SOURCE:
809 	case MCAST_UNBLOCK_SOURCE:
810 	{
811 		struct group_source_req greqs;
812 		struct ip_mreq_source mreqs;
813 		struct sockaddr_in *psin;
814 		int omode, add;
815 
816 		if (optlen != sizeof(struct group_source_req))
817 			goto e_inval;
818 		if (copy_from_user(&greqs, optval, sizeof(greqs))) {
819 			err = -EFAULT;
820 			break;
821 		}
822 		if (greqs.gsr_group.ss_family != AF_INET ||
823 		    greqs.gsr_source.ss_family != AF_INET) {
824 			err = -EADDRNOTAVAIL;
825 			break;
826 		}
827 		psin = (struct sockaddr_in *)&greqs.gsr_group;
828 		mreqs.imr_multiaddr = psin->sin_addr.s_addr;
829 		psin = (struct sockaddr_in *)&greqs.gsr_source;
830 		mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
831 		mreqs.imr_interface = 0; /* use index for mc_source */
832 
833 		if (optname == MCAST_BLOCK_SOURCE) {
834 			omode = MCAST_EXCLUDE;
835 			add = 1;
836 		} else if (optname == MCAST_UNBLOCK_SOURCE) {
837 			omode = MCAST_EXCLUDE;
838 			add = 0;
839 		} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
840 			struct ip_mreqn mreq;
841 
842 			psin = (struct sockaddr_in *)&greqs.gsr_group;
843 			mreq.imr_multiaddr = psin->sin_addr;
844 			mreq.imr_address.s_addr = 0;
845 			mreq.imr_ifindex = greqs.gsr_interface;
846 			err = ip_mc_join_group(sk, &mreq);
847 			if (err && err != -EADDRINUSE)
848 				break;
849 			greqs.gsr_interface = mreq.imr_ifindex;
850 			omode = MCAST_INCLUDE;
851 			add = 1;
852 		} else /* MCAST_LEAVE_SOURCE_GROUP */ {
853 			omode = MCAST_INCLUDE;
854 			add = 0;
855 		}
856 		err = ip_mc_source(add, omode, sk, &mreqs,
857 				   greqs.gsr_interface);
858 		break;
859 	}
860 	case MCAST_MSFILTER:
861 	{
862 		struct sockaddr_in *psin;
863 		struct ip_msfilter *msf = NULL;
864 		struct group_filter *gsf = NULL;
865 		int msize, i, ifindex;
866 
867 		if (optlen < GROUP_FILTER_SIZE(0))
868 			goto e_inval;
869 		if (optlen > sysctl_optmem_max) {
870 			err = -ENOBUFS;
871 			break;
872 		}
873 		gsf = kmalloc(optlen, GFP_KERNEL);
874 		if (!gsf) {
875 			err = -ENOBUFS;
876 			break;
877 		}
878 		err = -EFAULT;
879 		if (copy_from_user(gsf, optval, optlen))
880 			goto mc_msf_out;
881 
882 		/* numsrc >= (4G-140)/128 overflow in 32 bits */
883 		if (gsf->gf_numsrc >= 0x1ffffff ||
884 		    gsf->gf_numsrc > sysctl_igmp_max_msf) {
885 			err = -ENOBUFS;
886 			goto mc_msf_out;
887 		}
888 		if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
889 			err = -EINVAL;
890 			goto mc_msf_out;
891 		}
892 		msize = IP_MSFILTER_SIZE(gsf->gf_numsrc);
893 		msf = kmalloc(msize, GFP_KERNEL);
894 		if (!msf) {
895 			err = -ENOBUFS;
896 			goto mc_msf_out;
897 		}
898 		ifindex = gsf->gf_interface;
899 		psin = (struct sockaddr_in *)&gsf->gf_group;
900 		if (psin->sin_family != AF_INET) {
901 			err = -EADDRNOTAVAIL;
902 			goto mc_msf_out;
903 		}
904 		msf->imsf_multiaddr = psin->sin_addr.s_addr;
905 		msf->imsf_interface = 0;
906 		msf->imsf_fmode = gsf->gf_fmode;
907 		msf->imsf_numsrc = gsf->gf_numsrc;
908 		err = -EADDRNOTAVAIL;
909 		for (i = 0; i < gsf->gf_numsrc; ++i) {
910 			psin = (struct sockaddr_in *)&gsf->gf_slist[i];
911 
912 			if (psin->sin_family != AF_INET)
913 				goto mc_msf_out;
914 			msf->imsf_slist[i] = psin->sin_addr.s_addr;
915 		}
916 		kfree(gsf);
917 		gsf = NULL;
918 
919 		err = ip_mc_msfilter(sk, msf, ifindex);
920 mc_msf_out:
921 		kfree(msf);
922 		kfree(gsf);
923 		break;
924 	}
925 	case IP_MULTICAST_ALL:
926 		if (optlen < 1)
927 			goto e_inval;
928 		if (val != 0 && val != 1)
929 			goto e_inval;
930 		inet->mc_all = val;
931 		break;
932 	case IP_ROUTER_ALERT:
933 		err = ip_ra_control(sk, val ? 1 : 0, NULL);
934 		break;
935 
936 	case IP_FREEBIND:
937 		if (optlen < 1)
938 			goto e_inval;
939 		inet->freebind = !!val;
940 		break;
941 
942 	case IP_IPSEC_POLICY:
943 	case IP_XFRM_POLICY:
944 		err = -EPERM;
945 		if (!capable(CAP_NET_ADMIN))
946 			break;
947 		err = xfrm_user_policy(sk, optname, optval, optlen);
948 		break;
949 
950 	case IP_TRANSPARENT:
951 		if (!capable(CAP_NET_ADMIN)) {
952 			err = -EPERM;
953 			break;
954 		}
955 		if (optlen < 1)
956 			goto e_inval;
957 		inet->transparent = !!val;
958 		break;
959 
960 	case IP_MINTTL:
961 		if (optlen < 1)
962 			goto e_inval;
963 		if (val < 0 || val > 255)
964 			goto e_inval;
965 		inet->min_ttl = val;
966 		break;
967 
968 	default:
969 		err = -ENOPROTOOPT;
970 		break;
971 	}
972 	release_sock(sk);
973 	return err;
974 
975 e_inval:
976 	release_sock(sk);
977 	return -EINVAL;
978 }
979 
980 /**
981  * ip_queue_rcv_skb - Queue an skb into sock receive queue
982  * @sk: socket
983  * @skb: buffer
984  *
985  * Queues an skb into socket receive queue. If IP_CMSG_PKTINFO option
986  * is not set, we drop skb dst entry now, while dst cache line is hot.
987  */
988 int ip_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
989 {
990 	if (!(inet_sk(sk)->cmsg_flags & IP_CMSG_PKTINFO))
991 		skb_dst_drop(skb);
992 	return sock_queue_rcv_skb(sk, skb);
993 }
994 EXPORT_SYMBOL(ip_queue_rcv_skb);
995 
996 int ip_setsockopt(struct sock *sk, int level,
997 		int optname, char __user *optval, unsigned int optlen)
998 {
999 	int err;
1000 
1001 	if (level != SOL_IP)
1002 		return -ENOPROTOOPT;
1003 
1004 	err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1005 #ifdef CONFIG_NETFILTER
1006 	/* we need to exclude all possible ENOPROTOOPTs except default case */
1007 	if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1008 			optname != IP_IPSEC_POLICY &&
1009 			optname != IP_XFRM_POLICY &&
1010 			!ip_mroute_opt(optname)) {
1011 		lock_sock(sk);
1012 		err = nf_setsockopt(sk, PF_INET, optname, optval, optlen);
1013 		release_sock(sk);
1014 	}
1015 #endif
1016 	return err;
1017 }
1018 EXPORT_SYMBOL(ip_setsockopt);
1019 
1020 #ifdef CONFIG_COMPAT
1021 int compat_ip_setsockopt(struct sock *sk, int level, int optname,
1022 			 char __user *optval, unsigned int optlen)
1023 {
1024 	int err;
1025 
1026 	if (level != SOL_IP)
1027 		return -ENOPROTOOPT;
1028 
1029 	if (optname >= MCAST_JOIN_GROUP && optname <= MCAST_MSFILTER)
1030 		return compat_mc_setsockopt(sk, level, optname, optval, optlen,
1031 			ip_setsockopt);
1032 
1033 	err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1034 #ifdef CONFIG_NETFILTER
1035 	/* we need to exclude all possible ENOPROTOOPTs except default case */
1036 	if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1037 			optname != IP_IPSEC_POLICY &&
1038 			optname != IP_XFRM_POLICY &&
1039 			!ip_mroute_opt(optname)) {
1040 		lock_sock(sk);
1041 		err = compat_nf_setsockopt(sk, PF_INET, optname,
1042 					   optval, optlen);
1043 		release_sock(sk);
1044 	}
1045 #endif
1046 	return err;
1047 }
1048 EXPORT_SYMBOL(compat_ip_setsockopt);
1049 #endif
1050 
1051 /*
1052  *	Get the options. Note for future reference. The GET of IP options gets
1053  *	the _received_ ones. The set sets the _sent_ ones.
1054  */
1055 
1056 static int do_ip_getsockopt(struct sock *sk, int level, int optname,
1057 			    char __user *optval, int __user *optlen)
1058 {
1059 	struct inet_sock *inet = inet_sk(sk);
1060 	int val;
1061 	int len;
1062 
1063 	if (level != SOL_IP)
1064 		return -EOPNOTSUPP;
1065 
1066 	if (ip_mroute_opt(optname))
1067 		return ip_mroute_getsockopt(sk, optname, optval, optlen);
1068 
1069 	if (get_user(len, optlen))
1070 		return -EFAULT;
1071 	if (len < 0)
1072 		return -EINVAL;
1073 
1074 	lock_sock(sk);
1075 
1076 	switch (optname) {
1077 	case IP_OPTIONS:
1078 	{
1079 		unsigned char optbuf[sizeof(struct ip_options)+40];
1080 		struct ip_options * opt = (struct ip_options *)optbuf;
1081 		opt->optlen = 0;
1082 		if (inet->opt)
1083 			memcpy(optbuf, inet->opt,
1084 			       sizeof(struct ip_options)+
1085 			       inet->opt->optlen);
1086 		release_sock(sk);
1087 
1088 		if (opt->optlen == 0)
1089 			return put_user(0, optlen);
1090 
1091 		ip_options_undo(opt);
1092 
1093 		len = min_t(unsigned int, len, opt->optlen);
1094 		if (put_user(len, optlen))
1095 			return -EFAULT;
1096 		if (copy_to_user(optval, opt->__data, len))
1097 			return -EFAULT;
1098 		return 0;
1099 	}
1100 	case IP_PKTINFO:
1101 		val = (inet->cmsg_flags & IP_CMSG_PKTINFO) != 0;
1102 		break;
1103 	case IP_RECVTTL:
1104 		val = (inet->cmsg_flags & IP_CMSG_TTL) != 0;
1105 		break;
1106 	case IP_RECVTOS:
1107 		val = (inet->cmsg_flags & IP_CMSG_TOS) != 0;
1108 		break;
1109 	case IP_RECVOPTS:
1110 		val = (inet->cmsg_flags & IP_CMSG_RECVOPTS) != 0;
1111 		break;
1112 	case IP_RETOPTS:
1113 		val = (inet->cmsg_flags & IP_CMSG_RETOPTS) != 0;
1114 		break;
1115 	case IP_PASSSEC:
1116 		val = (inet->cmsg_flags & IP_CMSG_PASSSEC) != 0;
1117 		break;
1118 	case IP_RECVORIGDSTADDR:
1119 		val = (inet->cmsg_flags & IP_CMSG_ORIGDSTADDR) != 0;
1120 		break;
1121 	case IP_TOS:
1122 		val = inet->tos;
1123 		break;
1124 	case IP_TTL:
1125 		val = (inet->uc_ttl == -1 ?
1126 		       sysctl_ip_default_ttl :
1127 		       inet->uc_ttl);
1128 		break;
1129 	case IP_HDRINCL:
1130 		val = inet->hdrincl;
1131 		break;
1132 	case IP_MTU_DISCOVER:
1133 		val = inet->pmtudisc;
1134 		break;
1135 	case IP_MTU:
1136 	{
1137 		struct dst_entry *dst;
1138 		val = 0;
1139 		dst = sk_dst_get(sk);
1140 		if (dst) {
1141 			val = dst_mtu(dst);
1142 			dst_release(dst);
1143 		}
1144 		if (!val) {
1145 			release_sock(sk);
1146 			return -ENOTCONN;
1147 		}
1148 		break;
1149 	}
1150 	case IP_RECVERR:
1151 		val = inet->recverr;
1152 		break;
1153 	case IP_MULTICAST_TTL:
1154 		val = inet->mc_ttl;
1155 		break;
1156 	case IP_MULTICAST_LOOP:
1157 		val = inet->mc_loop;
1158 		break;
1159 	case IP_MULTICAST_IF:
1160 	{
1161 		struct in_addr addr;
1162 		len = min_t(unsigned int, len, sizeof(struct in_addr));
1163 		addr.s_addr = inet->mc_addr;
1164 		release_sock(sk);
1165 
1166 		if (put_user(len, optlen))
1167 			return -EFAULT;
1168 		if (copy_to_user(optval, &addr, len))
1169 			return -EFAULT;
1170 		return 0;
1171 	}
1172 	case IP_MSFILTER:
1173 	{
1174 		struct ip_msfilter msf;
1175 		int err;
1176 
1177 		if (len < IP_MSFILTER_SIZE(0)) {
1178 			release_sock(sk);
1179 			return -EINVAL;
1180 		}
1181 		if (copy_from_user(&msf, optval, IP_MSFILTER_SIZE(0))) {
1182 			release_sock(sk);
1183 			return -EFAULT;
1184 		}
1185 		err = ip_mc_msfget(sk, &msf,
1186 				   (struct ip_msfilter __user *)optval, optlen);
1187 		release_sock(sk);
1188 		return err;
1189 	}
1190 	case MCAST_MSFILTER:
1191 	{
1192 		struct group_filter gsf;
1193 		int err;
1194 
1195 		if (len < GROUP_FILTER_SIZE(0)) {
1196 			release_sock(sk);
1197 			return -EINVAL;
1198 		}
1199 		if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) {
1200 			release_sock(sk);
1201 			return -EFAULT;
1202 		}
1203 		err = ip_mc_gsfget(sk, &gsf,
1204 				   (struct group_filter __user *)optval,
1205 				   optlen);
1206 		release_sock(sk);
1207 		return err;
1208 	}
1209 	case IP_MULTICAST_ALL:
1210 		val = inet->mc_all;
1211 		break;
1212 	case IP_PKTOPTIONS:
1213 	{
1214 		struct msghdr msg;
1215 
1216 		release_sock(sk);
1217 
1218 		if (sk->sk_type != SOCK_STREAM)
1219 			return -ENOPROTOOPT;
1220 
1221 		msg.msg_control = optval;
1222 		msg.msg_controllen = len;
1223 		msg.msg_flags = 0;
1224 
1225 		if (inet->cmsg_flags & IP_CMSG_PKTINFO) {
1226 			struct in_pktinfo info;
1227 
1228 			info.ipi_addr.s_addr = inet->inet_rcv_saddr;
1229 			info.ipi_spec_dst.s_addr = inet->inet_rcv_saddr;
1230 			info.ipi_ifindex = inet->mc_index;
1231 			put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
1232 		}
1233 		if (inet->cmsg_flags & IP_CMSG_TTL) {
1234 			int hlim = inet->mc_ttl;
1235 			put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim);
1236 		}
1237 		len -= msg.msg_controllen;
1238 		return put_user(len, optlen);
1239 	}
1240 	case IP_FREEBIND:
1241 		val = inet->freebind;
1242 		break;
1243 	case IP_TRANSPARENT:
1244 		val = inet->transparent;
1245 		break;
1246 	case IP_MINTTL:
1247 		val = inet->min_ttl;
1248 		break;
1249 	default:
1250 		release_sock(sk);
1251 		return -ENOPROTOOPT;
1252 	}
1253 	release_sock(sk);
1254 
1255 	if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) {
1256 		unsigned char ucval = (unsigned char)val;
1257 		len = 1;
1258 		if (put_user(len, optlen))
1259 			return -EFAULT;
1260 		if (copy_to_user(optval, &ucval, 1))
1261 			return -EFAULT;
1262 	} else {
1263 		len = min_t(unsigned int, sizeof(int), len);
1264 		if (put_user(len, optlen))
1265 			return -EFAULT;
1266 		if (copy_to_user(optval, &val, len))
1267 			return -EFAULT;
1268 	}
1269 	return 0;
1270 }
1271 
1272 int ip_getsockopt(struct sock *sk, int level,
1273 		  int optname, char __user *optval, int __user *optlen)
1274 {
1275 	int err;
1276 
1277 	err = do_ip_getsockopt(sk, level, optname, optval, optlen);
1278 #ifdef CONFIG_NETFILTER
1279 	/* we need to exclude all possible ENOPROTOOPTs except default case */
1280 	if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1281 			!ip_mroute_opt(optname)) {
1282 		int len;
1283 
1284 		if (get_user(len, optlen))
1285 			return -EFAULT;
1286 
1287 		lock_sock(sk);
1288 		err = nf_getsockopt(sk, PF_INET, optname, optval,
1289 				&len);
1290 		release_sock(sk);
1291 		if (err >= 0)
1292 			err = put_user(len, optlen);
1293 		return err;
1294 	}
1295 #endif
1296 	return err;
1297 }
1298 EXPORT_SYMBOL(ip_getsockopt);
1299 
1300 #ifdef CONFIG_COMPAT
1301 int compat_ip_getsockopt(struct sock *sk, int level, int optname,
1302 			 char __user *optval, int __user *optlen)
1303 {
1304 	int err;
1305 
1306 	if (optname == MCAST_MSFILTER)
1307 		return compat_mc_getsockopt(sk, level, optname, optval, optlen,
1308 			ip_getsockopt);
1309 
1310 	err = do_ip_getsockopt(sk, level, optname, optval, optlen);
1311 
1312 #ifdef CONFIG_NETFILTER
1313 	/* we need to exclude all possible ENOPROTOOPTs except default case */
1314 	if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1315 			!ip_mroute_opt(optname)) {
1316 		int len;
1317 
1318 		if (get_user(len, optlen))
1319 			return -EFAULT;
1320 
1321 		lock_sock(sk);
1322 		err = compat_nf_getsockopt(sk, PF_INET, optname, optval, &len);
1323 		release_sock(sk);
1324 		if (err >= 0)
1325 			err = put_user(len, optlen);
1326 		return err;
1327 	}
1328 #endif
1329 	return err;
1330 }
1331 EXPORT_SYMBOL(compat_ip_getsockopt);
1332 #endif
1333