xref: /linux/net/compat.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
1 /*
2  * 32bit Socket syscall emulation. Based on arch/sparc64/kernel/sys_sparc32.c.
3  *
4  * Copyright (C) 2000		VA Linux Co
5  * Copyright (C) 2000		Don Dugger <n0ano@valinux.com>
6  * Copyright (C) 1999 		Arun Sharma <arun.sharma@intel.com>
7  * Copyright (C) 1997,1998 	Jakub Jelinek (jj@sunsite.mff.cuni.cz)
8  * Copyright (C) 1997 		David S. Miller (davem@caip.rutgers.edu)
9  * Copyright (C) 2000		Hewlett-Packard Co.
10  * Copyright (C) 2000		David Mosberger-Tang <davidm@hpl.hp.com>
11  * Copyright (C) 2000,2001	Andi Kleen, SuSE Labs
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/gfp.h>
16 #include <linux/fs.h>
17 #include <linux/types.h>
18 #include <linux/file.h>
19 #include <linux/icmpv6.h>
20 #include <linux/socket.h>
21 #include <linux/syscalls.h>
22 #include <linux/filter.h>
23 #include <linux/compat.h>
24 #include <linux/security.h>
25 #include <linux/audit.h>
26 #include <linux/export.h>
27 
28 #include <net/scm.h>
29 #include <net/sock.h>
30 #include <net/ip.h>
31 #include <net/ipv6.h>
32 #include <linux/uaccess.h>
33 #include <net/compat.h>
34 
35 int get_compat_msghdr(struct msghdr *kmsg,
36 		      struct compat_msghdr __user *umsg,
37 		      struct sockaddr __user **save_addr,
38 		      struct iovec **iov)
39 {
40 	compat_uptr_t uaddr, uiov, tmp3;
41 	compat_size_t nr_segs;
42 	ssize_t err;
43 
44 	if (!access_ok(VERIFY_READ, umsg, sizeof(*umsg)) ||
45 	    __get_user(uaddr, &umsg->msg_name) ||
46 	    __get_user(kmsg->msg_namelen, &umsg->msg_namelen) ||
47 	    __get_user(uiov, &umsg->msg_iov) ||
48 	    __get_user(nr_segs, &umsg->msg_iovlen) ||
49 	    __get_user(tmp3, &umsg->msg_control) ||
50 	    __get_user(kmsg->msg_controllen, &umsg->msg_controllen) ||
51 	    __get_user(kmsg->msg_flags, &umsg->msg_flags))
52 		return -EFAULT;
53 
54 	if (!uaddr)
55 		kmsg->msg_namelen = 0;
56 
57 	if (kmsg->msg_namelen < 0)
58 		return -EINVAL;
59 
60 	if (kmsg->msg_namelen > sizeof(struct sockaddr_storage))
61 		kmsg->msg_namelen = sizeof(struct sockaddr_storage);
62 	kmsg->msg_control = compat_ptr(tmp3);
63 
64 	if (save_addr)
65 		*save_addr = compat_ptr(uaddr);
66 
67 	if (uaddr && kmsg->msg_namelen) {
68 		if (!save_addr) {
69 			err = move_addr_to_kernel(compat_ptr(uaddr),
70 						  kmsg->msg_namelen,
71 						  kmsg->msg_name);
72 			if (err < 0)
73 				return err;
74 		}
75 	} else {
76 		kmsg->msg_name = NULL;
77 		kmsg->msg_namelen = 0;
78 	}
79 
80 	if (nr_segs > UIO_MAXIOV)
81 		return -EMSGSIZE;
82 
83 	kmsg->msg_iocb = NULL;
84 
85 	return compat_import_iovec(save_addr ? READ : WRITE,
86 				   compat_ptr(uiov), nr_segs,
87 				   UIO_FASTIOV, iov, &kmsg->msg_iter);
88 }
89 
90 /* Bleech... */
91 #define CMSG_COMPAT_ALIGN(len)	ALIGN((len), sizeof(s32))
92 
93 #define CMSG_COMPAT_DATA(cmsg)				\
94 	((void __user *)((char __user *)(cmsg) + sizeof(struct compat_cmsghdr)))
95 #define CMSG_COMPAT_SPACE(len)				\
96 	(sizeof(struct compat_cmsghdr) + CMSG_COMPAT_ALIGN(len))
97 #define CMSG_COMPAT_LEN(len)				\
98 	(sizeof(struct compat_cmsghdr) + (len))
99 
100 #define CMSG_COMPAT_FIRSTHDR(msg)			\
101 	(((msg)->msg_controllen) >= sizeof(struct compat_cmsghdr) ?	\
102 	 (struct compat_cmsghdr __user *)((msg)->msg_control) :		\
103 	 (struct compat_cmsghdr __user *)NULL)
104 
105 #define CMSG_COMPAT_OK(ucmlen, ucmsg, mhdr) \
106 	((ucmlen) >= sizeof(struct compat_cmsghdr) && \
107 	 (ucmlen) <= (unsigned long) \
108 	 ((mhdr)->msg_controllen - \
109 	  ((char *)(ucmsg) - (char *)(mhdr)->msg_control)))
110 
111 static inline struct compat_cmsghdr __user *cmsg_compat_nxthdr(struct msghdr *msg,
112 		struct compat_cmsghdr __user *cmsg, int cmsg_len)
113 {
114 	char __user *ptr = (char __user *)cmsg + CMSG_COMPAT_ALIGN(cmsg_len);
115 	if ((unsigned long)(ptr + 1 - (char __user *)msg->msg_control) >
116 			msg->msg_controllen)
117 		return NULL;
118 	return (struct compat_cmsghdr __user *)ptr;
119 }
120 
121 /* There is a lot of hair here because the alignment rules (and
122  * thus placement) of cmsg headers and length are different for
123  * 32-bit apps.  -DaveM
124  */
125 int cmsghdr_from_user_compat_to_kern(struct msghdr *kmsg, struct sock *sk,
126 			       unsigned char *stackbuf, int stackbuf_size)
127 {
128 	struct compat_cmsghdr __user *ucmsg;
129 	struct cmsghdr *kcmsg, *kcmsg_base;
130 	compat_size_t ucmlen;
131 	__kernel_size_t kcmlen, tmp;
132 	int err = -EFAULT;
133 
134 	BUILD_BUG_ON(sizeof(struct compat_cmsghdr) !=
135 		     CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)));
136 
137 	kcmlen = 0;
138 	kcmsg_base = kcmsg = (struct cmsghdr *)stackbuf;
139 	ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
140 	while (ucmsg != NULL) {
141 		if (get_user(ucmlen, &ucmsg->cmsg_len))
142 			return -EFAULT;
143 
144 		/* Catch bogons. */
145 		if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
146 			return -EINVAL;
147 
148 		tmp = ((ucmlen - sizeof(*ucmsg)) + sizeof(struct cmsghdr));
149 		tmp = CMSG_ALIGN(tmp);
150 		kcmlen += tmp;
151 		ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
152 	}
153 	if (kcmlen == 0)
154 		return -EINVAL;
155 
156 	/* The kcmlen holds the 64-bit version of the control length.
157 	 * It may not be modified as we do not stick it into the kmsg
158 	 * until we have successfully copied over all of the data
159 	 * from the user.
160 	 */
161 	if (kcmlen > stackbuf_size)
162 		kcmsg_base = kcmsg = sock_kmalloc(sk, kcmlen, GFP_KERNEL);
163 	if (kcmsg == NULL)
164 		return -ENOBUFS;
165 
166 	/* Now copy them over neatly. */
167 	memset(kcmsg, 0, kcmlen);
168 	ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
169 	while (ucmsg != NULL) {
170 		if (__get_user(ucmlen, &ucmsg->cmsg_len))
171 			goto Efault;
172 		if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
173 			goto Einval;
174 		tmp = ((ucmlen - sizeof(*ucmsg)) + sizeof(struct cmsghdr));
175 		if ((char *)kcmsg_base + kcmlen - (char *)kcmsg < CMSG_ALIGN(tmp))
176 			goto Einval;
177 		kcmsg->cmsg_len = tmp;
178 		tmp = CMSG_ALIGN(tmp);
179 		if (__get_user(kcmsg->cmsg_level, &ucmsg->cmsg_level) ||
180 		    __get_user(kcmsg->cmsg_type, &ucmsg->cmsg_type) ||
181 		    copy_from_user(CMSG_DATA(kcmsg),
182 				   CMSG_COMPAT_DATA(ucmsg),
183 				   (ucmlen - sizeof(*ucmsg))))
184 			goto Efault;
185 
186 		/* Advance. */
187 		kcmsg = (struct cmsghdr *)((char *)kcmsg + tmp);
188 		ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
189 	}
190 
191 	/* Ok, looks like we made it.  Hook it up and return success. */
192 	kmsg->msg_control = kcmsg_base;
193 	kmsg->msg_controllen = kcmlen;
194 	return 0;
195 
196 Einval:
197 	err = -EINVAL;
198 Efault:
199 	if (kcmsg_base != (struct cmsghdr *)stackbuf)
200 		sock_kfree_s(sk, kcmsg_base, kcmlen);
201 	return err;
202 }
203 
204 int put_cmsg_compat(struct msghdr *kmsg, int level, int type, int len, void *data)
205 {
206 	struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
207 	struct compat_cmsghdr cmhdr;
208 	struct compat_timeval ctv;
209 	struct compat_timespec cts[3];
210 	int cmlen;
211 
212 	if (cm == NULL || kmsg->msg_controllen < sizeof(*cm)) {
213 		kmsg->msg_flags |= MSG_CTRUNC;
214 		return 0; /* XXX: return error? check spec. */
215 	}
216 
217 	if (!COMPAT_USE_64BIT_TIME) {
218 		if (level == SOL_SOCKET && type == SCM_TIMESTAMP) {
219 			struct timeval *tv = (struct timeval *)data;
220 			ctv.tv_sec = tv->tv_sec;
221 			ctv.tv_usec = tv->tv_usec;
222 			data = &ctv;
223 			len = sizeof(ctv);
224 		}
225 		if (level == SOL_SOCKET &&
226 		    (type == SCM_TIMESTAMPNS || type == SCM_TIMESTAMPING)) {
227 			int count = type == SCM_TIMESTAMPNS ? 1 : 3;
228 			int i;
229 			struct timespec *ts = (struct timespec *)data;
230 			for (i = 0; i < count; i++) {
231 				cts[i].tv_sec = ts[i].tv_sec;
232 				cts[i].tv_nsec = ts[i].tv_nsec;
233 			}
234 			data = &cts;
235 			len = sizeof(cts[0]) * count;
236 		}
237 	}
238 
239 	cmlen = CMSG_COMPAT_LEN(len);
240 	if (kmsg->msg_controllen < cmlen) {
241 		kmsg->msg_flags |= MSG_CTRUNC;
242 		cmlen = kmsg->msg_controllen;
243 	}
244 	cmhdr.cmsg_level = level;
245 	cmhdr.cmsg_type = type;
246 	cmhdr.cmsg_len = cmlen;
247 
248 	if (copy_to_user(cm, &cmhdr, sizeof cmhdr))
249 		return -EFAULT;
250 	if (copy_to_user(CMSG_COMPAT_DATA(cm), data, cmlen - sizeof(struct compat_cmsghdr)))
251 		return -EFAULT;
252 	cmlen = CMSG_COMPAT_SPACE(len);
253 	if (kmsg->msg_controllen < cmlen)
254 		cmlen = kmsg->msg_controllen;
255 	kmsg->msg_control += cmlen;
256 	kmsg->msg_controllen -= cmlen;
257 	return 0;
258 }
259 
260 void scm_detach_fds_compat(struct msghdr *kmsg, struct scm_cookie *scm)
261 {
262 	struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
263 	int fdmax = (kmsg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int);
264 	int fdnum = scm->fp->count;
265 	struct file **fp = scm->fp->fp;
266 	int __user *cmfptr;
267 	int err = 0, i;
268 
269 	if (fdnum < fdmax)
270 		fdmax = fdnum;
271 
272 	for (i = 0, cmfptr = (int __user *) CMSG_COMPAT_DATA(cm); i < fdmax; i++, cmfptr++) {
273 		int new_fd;
274 		err = security_file_receive(fp[i]);
275 		if (err)
276 			break;
277 		err = get_unused_fd_flags(MSG_CMSG_CLOEXEC & kmsg->msg_flags
278 					  ? O_CLOEXEC : 0);
279 		if (err < 0)
280 			break;
281 		new_fd = err;
282 		err = put_user(new_fd, cmfptr);
283 		if (err) {
284 			put_unused_fd(new_fd);
285 			break;
286 		}
287 		/* Bump the usage count and install the file. */
288 		fd_install(new_fd, get_file(fp[i]));
289 	}
290 
291 	if (i > 0) {
292 		int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
293 		err = put_user(SOL_SOCKET, &cm->cmsg_level);
294 		if (!err)
295 			err = put_user(SCM_RIGHTS, &cm->cmsg_type);
296 		if (!err)
297 			err = put_user(cmlen, &cm->cmsg_len);
298 		if (!err) {
299 			cmlen = CMSG_COMPAT_SPACE(i * sizeof(int));
300 			kmsg->msg_control += cmlen;
301 			kmsg->msg_controllen -= cmlen;
302 		}
303 	}
304 	if (i < fdnum)
305 		kmsg->msg_flags |= MSG_CTRUNC;
306 
307 	/*
308 	 * All of the files that fit in the message have had their
309 	 * usage counts incremented, so we just free the list.
310 	 */
311 	__scm_destroy(scm);
312 }
313 
314 /* allocate a 64-bit sock_fprog on the user stack for duration of syscall. */
315 struct sock_fprog __user *get_compat_bpf_fprog(char __user *optval)
316 {
317 	struct compat_sock_fprog __user *fprog32 = (struct compat_sock_fprog __user *)optval;
318 	struct sock_fprog __user *kfprog = compat_alloc_user_space(sizeof(struct sock_fprog));
319 	compat_uptr_t ptr;
320 	u16 len;
321 
322 	if (!access_ok(VERIFY_READ, fprog32, sizeof(*fprog32)) ||
323 	    !access_ok(VERIFY_WRITE, kfprog, sizeof(struct sock_fprog)) ||
324 	    __get_user(len, &fprog32->len) ||
325 	    __get_user(ptr, &fprog32->filter) ||
326 	    __put_user(len, &kfprog->len) ||
327 	    __put_user(compat_ptr(ptr), &kfprog->filter))
328 		return NULL;
329 
330 	return kfprog;
331 }
332 EXPORT_SYMBOL_GPL(get_compat_bpf_fprog);
333 
334 static int do_set_attach_filter(struct socket *sock, int level, int optname,
335 				char __user *optval, unsigned int optlen)
336 {
337 	struct sock_fprog __user *kfprog;
338 
339 	kfprog = get_compat_bpf_fprog(optval);
340 	if (!kfprog)
341 		return -EFAULT;
342 
343 	return sock_setsockopt(sock, level, optname, (char __user *)kfprog,
344 			      sizeof(struct sock_fprog));
345 }
346 
347 static int do_set_sock_timeout(struct socket *sock, int level,
348 		int optname, char __user *optval, unsigned int optlen)
349 {
350 	struct compat_timeval __user *up = (struct compat_timeval __user *)optval;
351 	struct timeval ktime;
352 	mm_segment_t old_fs;
353 	int err;
354 
355 	if (optlen < sizeof(*up))
356 		return -EINVAL;
357 	if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
358 	    __get_user(ktime.tv_sec, &up->tv_sec) ||
359 	    __get_user(ktime.tv_usec, &up->tv_usec))
360 		return -EFAULT;
361 	old_fs = get_fs();
362 	set_fs(KERNEL_DS);
363 	err = sock_setsockopt(sock, level, optname, (char *)&ktime, sizeof(ktime));
364 	set_fs(old_fs);
365 
366 	return err;
367 }
368 
369 static int compat_sock_setsockopt(struct socket *sock, int level, int optname,
370 				char __user *optval, unsigned int optlen)
371 {
372 	if (optname == SO_ATTACH_FILTER ||
373 	    optname == SO_ATTACH_REUSEPORT_CBPF)
374 		return do_set_attach_filter(sock, level, optname,
375 					    optval, optlen);
376 	if (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO)
377 		return do_set_sock_timeout(sock, level, optname, optval, optlen);
378 
379 	return sock_setsockopt(sock, level, optname, optval, optlen);
380 }
381 
382 COMPAT_SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
383 		       char __user *, optval, unsigned int, optlen)
384 {
385 	int err;
386 	struct socket *sock = sockfd_lookup(fd, &err);
387 
388 	if (sock) {
389 		err = security_socket_setsockopt(sock, level, optname);
390 		if (err) {
391 			sockfd_put(sock);
392 			return err;
393 		}
394 
395 		if (level == SOL_SOCKET)
396 			err = compat_sock_setsockopt(sock, level,
397 					optname, optval, optlen);
398 		else if (sock->ops->compat_setsockopt)
399 			err = sock->ops->compat_setsockopt(sock, level,
400 					optname, optval, optlen);
401 		else
402 			err = sock->ops->setsockopt(sock, level,
403 					optname, optval, optlen);
404 		sockfd_put(sock);
405 	}
406 	return err;
407 }
408 
409 static int do_get_sock_timeout(struct socket *sock, int level, int optname,
410 		char __user *optval, int __user *optlen)
411 {
412 	struct compat_timeval __user *up;
413 	struct timeval ktime;
414 	mm_segment_t old_fs;
415 	int len, err;
416 
417 	up = (struct compat_timeval __user *) optval;
418 	if (get_user(len, optlen))
419 		return -EFAULT;
420 	if (len < sizeof(*up))
421 		return -EINVAL;
422 	len = sizeof(ktime);
423 	old_fs = get_fs();
424 	set_fs(KERNEL_DS);
425 	err = sock_getsockopt(sock, level, optname, (char *) &ktime, &len);
426 	set_fs(old_fs);
427 
428 	if (!err) {
429 		if (put_user(sizeof(*up), optlen) ||
430 		    !access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
431 		    __put_user(ktime.tv_sec, &up->tv_sec) ||
432 		    __put_user(ktime.tv_usec, &up->tv_usec))
433 			err = -EFAULT;
434 	}
435 	return err;
436 }
437 
438 static int compat_sock_getsockopt(struct socket *sock, int level, int optname,
439 				char __user *optval, int __user *optlen)
440 {
441 	if (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO)
442 		return do_get_sock_timeout(sock, level, optname, optval, optlen);
443 	return sock_getsockopt(sock, level, optname, optval, optlen);
444 }
445 
446 int compat_sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
447 {
448 	struct compat_timeval __user *ctv;
449 	int err;
450 	struct timeval tv;
451 
452 	if (COMPAT_USE_64BIT_TIME)
453 		return sock_get_timestamp(sk, userstamp);
454 
455 	ctv = (struct compat_timeval __user *) userstamp;
456 	err = -ENOENT;
457 	if (!sock_flag(sk, SOCK_TIMESTAMP))
458 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
459 	tv = ktime_to_timeval(sk->sk_stamp);
460 	if (tv.tv_sec == -1)
461 		return err;
462 	if (tv.tv_sec == 0) {
463 		sk->sk_stamp = ktime_get_real();
464 		tv = ktime_to_timeval(sk->sk_stamp);
465 	}
466 	err = 0;
467 	if (put_user(tv.tv_sec, &ctv->tv_sec) ||
468 			put_user(tv.tv_usec, &ctv->tv_usec))
469 		err = -EFAULT;
470 	return err;
471 }
472 EXPORT_SYMBOL(compat_sock_get_timestamp);
473 
474 int compat_sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
475 {
476 	struct compat_timespec __user *ctv;
477 	int err;
478 	struct timespec ts;
479 
480 	if (COMPAT_USE_64BIT_TIME)
481 		return sock_get_timestampns (sk, userstamp);
482 
483 	ctv = (struct compat_timespec __user *) userstamp;
484 	err = -ENOENT;
485 	if (!sock_flag(sk, SOCK_TIMESTAMP))
486 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
487 	ts = ktime_to_timespec(sk->sk_stamp);
488 	if (ts.tv_sec == -1)
489 		return err;
490 	if (ts.tv_sec == 0) {
491 		sk->sk_stamp = ktime_get_real();
492 		ts = ktime_to_timespec(sk->sk_stamp);
493 	}
494 	err = 0;
495 	if (put_user(ts.tv_sec, &ctv->tv_sec) ||
496 			put_user(ts.tv_nsec, &ctv->tv_nsec))
497 		err = -EFAULT;
498 	return err;
499 }
500 EXPORT_SYMBOL(compat_sock_get_timestampns);
501 
502 COMPAT_SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname,
503 		       char __user *, optval, int __user *, optlen)
504 {
505 	int err;
506 	struct socket *sock = sockfd_lookup(fd, &err);
507 
508 	if (sock) {
509 		err = security_socket_getsockopt(sock, level, optname);
510 		if (err) {
511 			sockfd_put(sock);
512 			return err;
513 		}
514 
515 		if (level == SOL_SOCKET)
516 			err = compat_sock_getsockopt(sock, level,
517 					optname, optval, optlen);
518 		else if (sock->ops->compat_getsockopt)
519 			err = sock->ops->compat_getsockopt(sock, level,
520 					optname, optval, optlen);
521 		else
522 			err = sock->ops->getsockopt(sock, level,
523 					optname, optval, optlen);
524 		sockfd_put(sock);
525 	}
526 	return err;
527 }
528 
529 struct compat_group_req {
530 	__u32				 gr_interface;
531 	struct __kernel_sockaddr_storage gr_group
532 		__aligned(4);
533 } __packed;
534 
535 struct compat_group_source_req {
536 	__u32				 gsr_interface;
537 	struct __kernel_sockaddr_storage gsr_group
538 		__aligned(4);
539 	struct __kernel_sockaddr_storage gsr_source
540 		__aligned(4);
541 } __packed;
542 
543 struct compat_group_filter {
544 	__u32				 gf_interface;
545 	struct __kernel_sockaddr_storage gf_group
546 		__aligned(4);
547 	__u32				 gf_fmode;
548 	__u32				 gf_numsrc;
549 	struct __kernel_sockaddr_storage gf_slist[1]
550 		__aligned(4);
551 } __packed;
552 
553 #define __COMPAT_GF0_SIZE (sizeof(struct compat_group_filter) - \
554 			sizeof(struct __kernel_sockaddr_storage))
555 
556 
557 int compat_mc_setsockopt(struct sock *sock, int level, int optname,
558 	char __user *optval, unsigned int optlen,
559 	int (*setsockopt)(struct sock *, int, int, char __user *, unsigned int))
560 {
561 	char __user	*koptval = optval;
562 	int		koptlen = optlen;
563 
564 	switch (optname) {
565 	case MCAST_JOIN_GROUP:
566 	case MCAST_LEAVE_GROUP:
567 	{
568 		struct compat_group_req __user *gr32 = (void *)optval;
569 		struct group_req __user *kgr =
570 			compat_alloc_user_space(sizeof(struct group_req));
571 		u32 interface;
572 
573 		if (!access_ok(VERIFY_READ, gr32, sizeof(*gr32)) ||
574 		    !access_ok(VERIFY_WRITE, kgr, sizeof(struct group_req)) ||
575 		    __get_user(interface, &gr32->gr_interface) ||
576 		    __put_user(interface, &kgr->gr_interface) ||
577 		    copy_in_user(&kgr->gr_group, &gr32->gr_group,
578 				sizeof(kgr->gr_group)))
579 			return -EFAULT;
580 		koptval = (char __user *)kgr;
581 		koptlen = sizeof(struct group_req);
582 		break;
583 	}
584 	case MCAST_JOIN_SOURCE_GROUP:
585 	case MCAST_LEAVE_SOURCE_GROUP:
586 	case MCAST_BLOCK_SOURCE:
587 	case MCAST_UNBLOCK_SOURCE:
588 	{
589 		struct compat_group_source_req __user *gsr32 = (void *)optval;
590 		struct group_source_req __user *kgsr = compat_alloc_user_space(
591 			sizeof(struct group_source_req));
592 		u32 interface;
593 
594 		if (!access_ok(VERIFY_READ, gsr32, sizeof(*gsr32)) ||
595 		    !access_ok(VERIFY_WRITE, kgsr,
596 			sizeof(struct group_source_req)) ||
597 		    __get_user(interface, &gsr32->gsr_interface) ||
598 		    __put_user(interface, &kgsr->gsr_interface) ||
599 		    copy_in_user(&kgsr->gsr_group, &gsr32->gsr_group,
600 				sizeof(kgsr->gsr_group)) ||
601 		    copy_in_user(&kgsr->gsr_source, &gsr32->gsr_source,
602 				sizeof(kgsr->gsr_source)))
603 			return -EFAULT;
604 		koptval = (char __user *)kgsr;
605 		koptlen = sizeof(struct group_source_req);
606 		break;
607 	}
608 	case MCAST_MSFILTER:
609 	{
610 		struct compat_group_filter __user *gf32 = (void *)optval;
611 		struct group_filter __user *kgf;
612 		u32 interface, fmode, numsrc;
613 
614 		if (!access_ok(VERIFY_READ, gf32, __COMPAT_GF0_SIZE) ||
615 		    __get_user(interface, &gf32->gf_interface) ||
616 		    __get_user(fmode, &gf32->gf_fmode) ||
617 		    __get_user(numsrc, &gf32->gf_numsrc))
618 			return -EFAULT;
619 		koptlen = optlen + sizeof(struct group_filter) -
620 				sizeof(struct compat_group_filter);
621 		if (koptlen < GROUP_FILTER_SIZE(numsrc))
622 			return -EINVAL;
623 		kgf = compat_alloc_user_space(koptlen);
624 		if (!access_ok(VERIFY_WRITE, kgf, koptlen) ||
625 		    __put_user(interface, &kgf->gf_interface) ||
626 		    __put_user(fmode, &kgf->gf_fmode) ||
627 		    __put_user(numsrc, &kgf->gf_numsrc) ||
628 		    copy_in_user(&kgf->gf_group, &gf32->gf_group,
629 				sizeof(kgf->gf_group)) ||
630 		    (numsrc && copy_in_user(kgf->gf_slist, gf32->gf_slist,
631 				numsrc * sizeof(kgf->gf_slist[0]))))
632 			return -EFAULT;
633 		koptval = (char __user *)kgf;
634 		break;
635 	}
636 
637 	default:
638 		break;
639 	}
640 	return setsockopt(sock, level, optname, koptval, koptlen);
641 }
642 EXPORT_SYMBOL(compat_mc_setsockopt);
643 
644 int compat_mc_getsockopt(struct sock *sock, int level, int optname,
645 	char __user *optval, int __user *optlen,
646 	int (*getsockopt)(struct sock *, int, int, char __user *, int __user *))
647 {
648 	struct compat_group_filter __user *gf32 = (void *)optval;
649 	struct group_filter __user *kgf;
650 	int __user	*koptlen;
651 	u32 interface, fmode, numsrc;
652 	int klen, ulen, err;
653 
654 	if (optname != MCAST_MSFILTER)
655 		return getsockopt(sock, level, optname, optval, optlen);
656 
657 	koptlen = compat_alloc_user_space(sizeof(*koptlen));
658 	if (!access_ok(VERIFY_READ, optlen, sizeof(*optlen)) ||
659 	    __get_user(ulen, optlen))
660 		return -EFAULT;
661 
662 	/* adjust len for pad */
663 	klen = ulen + sizeof(*kgf) - sizeof(*gf32);
664 
665 	if (klen < GROUP_FILTER_SIZE(0))
666 		return -EINVAL;
667 
668 	if (!access_ok(VERIFY_WRITE, koptlen, sizeof(*koptlen)) ||
669 	    __put_user(klen, koptlen))
670 		return -EFAULT;
671 
672 	/* have to allow space for previous compat_alloc_user_space, too */
673 	kgf = compat_alloc_user_space(klen+sizeof(*optlen));
674 
675 	if (!access_ok(VERIFY_READ, gf32, __COMPAT_GF0_SIZE) ||
676 	    __get_user(interface, &gf32->gf_interface) ||
677 	    __get_user(fmode, &gf32->gf_fmode) ||
678 	    __get_user(numsrc, &gf32->gf_numsrc) ||
679 	    __put_user(interface, &kgf->gf_interface) ||
680 	    __put_user(fmode, &kgf->gf_fmode) ||
681 	    __put_user(numsrc, &kgf->gf_numsrc) ||
682 	    copy_in_user(&kgf->gf_group, &gf32->gf_group, sizeof(kgf->gf_group)))
683 		return -EFAULT;
684 
685 	err = getsockopt(sock, level, optname, (char __user *)kgf, koptlen);
686 	if (err)
687 		return err;
688 
689 	if (!access_ok(VERIFY_READ, koptlen, sizeof(*koptlen)) ||
690 	    __get_user(klen, koptlen))
691 		return -EFAULT;
692 
693 	ulen = klen - (sizeof(*kgf)-sizeof(*gf32));
694 
695 	if (!access_ok(VERIFY_WRITE, optlen, sizeof(*optlen)) ||
696 	    __put_user(ulen, optlen))
697 		return -EFAULT;
698 
699 	if (!access_ok(VERIFY_READ, kgf, klen) ||
700 	    !access_ok(VERIFY_WRITE, gf32, ulen) ||
701 	    __get_user(interface, &kgf->gf_interface) ||
702 	    __get_user(fmode, &kgf->gf_fmode) ||
703 	    __get_user(numsrc, &kgf->gf_numsrc) ||
704 	    __put_user(interface, &gf32->gf_interface) ||
705 	    __put_user(fmode, &gf32->gf_fmode) ||
706 	    __put_user(numsrc, &gf32->gf_numsrc))
707 		return -EFAULT;
708 	if (numsrc) {
709 		int copylen;
710 
711 		klen -= GROUP_FILTER_SIZE(0);
712 		copylen = numsrc * sizeof(gf32->gf_slist[0]);
713 		if (copylen > klen)
714 			copylen = klen;
715 		if (copy_in_user(gf32->gf_slist, kgf->gf_slist, copylen))
716 			return -EFAULT;
717 	}
718 	return err;
719 }
720 EXPORT_SYMBOL(compat_mc_getsockopt);
721 
722 
723 /* Argument list sizes for compat_sys_socketcall */
724 #define AL(x) ((x) * sizeof(u32))
725 static unsigned char nas[21] = {
726 	AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
727 	AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
728 	AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
729 	AL(4), AL(5), AL(4)
730 };
731 #undef AL
732 
733 COMPAT_SYSCALL_DEFINE3(sendmsg, int, fd, struct compat_msghdr __user *, msg, unsigned int, flags)
734 {
735 	return __sys_sendmsg(fd, (struct user_msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
736 }
737 
738 COMPAT_SYSCALL_DEFINE4(sendmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
739 		       unsigned int, vlen, unsigned int, flags)
740 {
741 	return __sys_sendmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
742 			      flags | MSG_CMSG_COMPAT);
743 }
744 
745 COMPAT_SYSCALL_DEFINE3(recvmsg, int, fd, struct compat_msghdr __user *, msg, unsigned int, flags)
746 {
747 	return __sys_recvmsg(fd, (struct user_msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
748 }
749 
750 COMPAT_SYSCALL_DEFINE4(recv, int, fd, void __user *, buf, compat_size_t, len, unsigned int, flags)
751 {
752 	return sys_recv(fd, buf, len, flags | MSG_CMSG_COMPAT);
753 }
754 
755 COMPAT_SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, buf, compat_size_t, len,
756 		       unsigned int, flags, struct sockaddr __user *, addr,
757 		       int __user *, addrlen)
758 {
759 	return sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr, addrlen);
760 }
761 
762 COMPAT_SYSCALL_DEFINE5(recvmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
763 		       unsigned int, vlen, unsigned int, flags,
764 		       struct compat_timespec __user *, timeout)
765 {
766 	int datagrams;
767 	struct timespec ktspec;
768 
769 	if (timeout == NULL)
770 		return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
771 				      flags | MSG_CMSG_COMPAT, NULL);
772 
773 	if (compat_get_timespec(&ktspec, timeout))
774 		return -EFAULT;
775 
776 	datagrams = __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
777 				   flags | MSG_CMSG_COMPAT, &ktspec);
778 	if (datagrams > 0 && compat_put_timespec(&ktspec, timeout))
779 		datagrams = -EFAULT;
780 
781 	return datagrams;
782 }
783 
784 COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args)
785 {
786 	u32 a[AUDITSC_ARGS];
787 	unsigned int len;
788 	u32 a0, a1;
789 	int ret;
790 
791 	if (call < SYS_SOCKET || call > SYS_SENDMMSG)
792 		return -EINVAL;
793 	len = nas[call];
794 	if (len > sizeof(a))
795 		return -EINVAL;
796 
797 	if (copy_from_user(a, args, len))
798 		return -EFAULT;
799 
800 	ret = audit_socketcall_compat(len / sizeof(a[0]), a);
801 	if (ret)
802 		return ret;
803 
804 	a0 = a[0];
805 	a1 = a[1];
806 
807 	switch (call) {
808 	case SYS_SOCKET:
809 		ret = sys_socket(a0, a1, a[2]);
810 		break;
811 	case SYS_BIND:
812 		ret = sys_bind(a0, compat_ptr(a1), a[2]);
813 		break;
814 	case SYS_CONNECT:
815 		ret = sys_connect(a0, compat_ptr(a1), a[2]);
816 		break;
817 	case SYS_LISTEN:
818 		ret = sys_listen(a0, a1);
819 		break;
820 	case SYS_ACCEPT:
821 		ret = sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0);
822 		break;
823 	case SYS_GETSOCKNAME:
824 		ret = sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]));
825 		break;
826 	case SYS_GETPEERNAME:
827 		ret = sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2]));
828 		break;
829 	case SYS_SOCKETPAIR:
830 		ret = sys_socketpair(a0, a1, a[2], compat_ptr(a[3]));
831 		break;
832 	case SYS_SEND:
833 		ret = sys_send(a0, compat_ptr(a1), a[2], a[3]);
834 		break;
835 	case SYS_SENDTO:
836 		ret = sys_sendto(a0, compat_ptr(a1), a[2], a[3], compat_ptr(a[4]), a[5]);
837 		break;
838 	case SYS_RECV:
839 		ret = compat_sys_recv(a0, compat_ptr(a1), a[2], a[3]);
840 		break;
841 	case SYS_RECVFROM:
842 		ret = compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
843 					  compat_ptr(a[4]), compat_ptr(a[5]));
844 		break;
845 	case SYS_SHUTDOWN:
846 		ret = sys_shutdown(a0, a1);
847 		break;
848 	case SYS_SETSOCKOPT:
849 		ret = compat_sys_setsockopt(a0, a1, a[2],
850 				compat_ptr(a[3]), a[4]);
851 		break;
852 	case SYS_GETSOCKOPT:
853 		ret = compat_sys_getsockopt(a0, a1, a[2],
854 				compat_ptr(a[3]), compat_ptr(a[4]));
855 		break;
856 	case SYS_SENDMSG:
857 		ret = compat_sys_sendmsg(a0, compat_ptr(a1), a[2]);
858 		break;
859 	case SYS_SENDMMSG:
860 		ret = compat_sys_sendmmsg(a0, compat_ptr(a1), a[2], a[3]);
861 		break;
862 	case SYS_RECVMSG:
863 		ret = compat_sys_recvmsg(a0, compat_ptr(a1), a[2]);
864 		break;
865 	case SYS_RECVMMSG:
866 		ret = compat_sys_recvmmsg(a0, compat_ptr(a1), a[2], a[3],
867 					  compat_ptr(a[4]));
868 		break;
869 	case SYS_ACCEPT4:
870 		ret = sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]);
871 		break;
872 	default:
873 		ret = -EINVAL;
874 		break;
875 	}
876 	return ret;
877 }
878