xref: /linux/net/compat.c (revision 4949009eb8d40a441dcddcd96e101e77d31cf1b2)
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/export.h>
26 
27 #include <net/scm.h>
28 #include <net/sock.h>
29 #include <net/ip.h>
30 #include <net/ipv6.h>
31 #include <asm/uaccess.h>
32 #include <net/compat.h>
33 
34 ssize_t get_compat_msghdr(struct msghdr *kmsg,
35 			  struct compat_msghdr __user *umsg,
36 			  struct sockaddr __user **save_addr,
37 			  struct iovec **iov)
38 {
39 	compat_uptr_t uaddr, uiov, tmp3;
40 	compat_size_t nr_segs;
41 	ssize_t err;
42 
43 	if (!access_ok(VERIFY_READ, umsg, sizeof(*umsg)) ||
44 	    __get_user(uaddr, &umsg->msg_name) ||
45 	    __get_user(kmsg->msg_namelen, &umsg->msg_namelen) ||
46 	    __get_user(uiov, &umsg->msg_iov) ||
47 	    __get_user(nr_segs, &umsg->msg_iovlen) ||
48 	    __get_user(tmp3, &umsg->msg_control) ||
49 	    __get_user(kmsg->msg_controllen, &umsg->msg_controllen) ||
50 	    __get_user(kmsg->msg_flags, &umsg->msg_flags))
51 		return -EFAULT;
52 	if (kmsg->msg_namelen > sizeof(struct sockaddr_storage))
53 		kmsg->msg_namelen = sizeof(struct sockaddr_storage);
54 	kmsg->msg_control = compat_ptr(tmp3);
55 
56 	if (save_addr)
57 		*save_addr = compat_ptr(uaddr);
58 
59 	if (uaddr && kmsg->msg_namelen) {
60 		if (!save_addr) {
61 			err = move_addr_to_kernel(compat_ptr(uaddr),
62 						  kmsg->msg_namelen,
63 						  kmsg->msg_name);
64 			if (err < 0)
65 				return err;
66 		}
67 	} else {
68 		kmsg->msg_name = NULL;
69 		kmsg->msg_namelen = 0;
70 	}
71 
72 	if (nr_segs > UIO_MAXIOV)
73 		return -EMSGSIZE;
74 
75 	err = compat_rw_copy_check_uvector(save_addr ? READ : WRITE,
76 					   compat_ptr(uiov), nr_segs,
77 					   UIO_FASTIOV, *iov, iov);
78 	if (err >= 0)
79 		iov_iter_init(&kmsg->msg_iter, save_addr ? READ : WRITE,
80 			      *iov, nr_segs, err);
81 	return err;
82 }
83 
84 /* Bleech... */
85 #define CMSG_COMPAT_ALIGN(len)	ALIGN((len), sizeof(s32))
86 
87 #define CMSG_COMPAT_DATA(cmsg)				\
88 	((void __user *)((char __user *)(cmsg) + CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr))))
89 #define CMSG_COMPAT_SPACE(len)				\
90 	(CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)) + CMSG_COMPAT_ALIGN(len))
91 #define CMSG_COMPAT_LEN(len)				\
92 	(CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)) + (len))
93 
94 #define CMSG_COMPAT_FIRSTHDR(msg)			\
95 	(((msg)->msg_controllen) >= sizeof(struct compat_cmsghdr) ?	\
96 	 (struct compat_cmsghdr __user *)((msg)->msg_control) :		\
97 	 (struct compat_cmsghdr __user *)NULL)
98 
99 #define CMSG_COMPAT_OK(ucmlen, ucmsg, mhdr) \
100 	((ucmlen) >= sizeof(struct compat_cmsghdr) && \
101 	 (ucmlen) <= (unsigned long) \
102 	 ((mhdr)->msg_controllen - \
103 	  ((char *)(ucmsg) - (char *)(mhdr)->msg_control)))
104 
105 static inline struct compat_cmsghdr __user *cmsg_compat_nxthdr(struct msghdr *msg,
106 		struct compat_cmsghdr __user *cmsg, int cmsg_len)
107 {
108 	char __user *ptr = (char __user *)cmsg + CMSG_COMPAT_ALIGN(cmsg_len);
109 	if ((unsigned long)(ptr + 1 - (char __user *)msg->msg_control) >
110 			msg->msg_controllen)
111 		return NULL;
112 	return (struct compat_cmsghdr __user *)ptr;
113 }
114 
115 /* There is a lot of hair here because the alignment rules (and
116  * thus placement) of cmsg headers and length are different for
117  * 32-bit apps.  -DaveM
118  */
119 int cmsghdr_from_user_compat_to_kern(struct msghdr *kmsg, struct sock *sk,
120 			       unsigned char *stackbuf, int stackbuf_size)
121 {
122 	struct compat_cmsghdr __user *ucmsg;
123 	struct cmsghdr *kcmsg, *kcmsg_base;
124 	compat_size_t ucmlen;
125 	__kernel_size_t kcmlen, tmp;
126 	int err = -EFAULT;
127 
128 	kcmlen = 0;
129 	kcmsg_base = kcmsg = (struct cmsghdr *)stackbuf;
130 	ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
131 	while (ucmsg != NULL) {
132 		if (get_user(ucmlen, &ucmsg->cmsg_len))
133 			return -EFAULT;
134 
135 		/* Catch bogons. */
136 		if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
137 			return -EINVAL;
138 
139 		tmp = ((ucmlen - CMSG_COMPAT_ALIGN(sizeof(*ucmsg))) +
140 		       CMSG_ALIGN(sizeof(struct cmsghdr)));
141 		tmp = CMSG_ALIGN(tmp);
142 		kcmlen += tmp;
143 		ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
144 	}
145 	if (kcmlen == 0)
146 		return -EINVAL;
147 
148 	/* The kcmlen holds the 64-bit version of the control length.
149 	 * It may not be modified as we do not stick it into the kmsg
150 	 * until we have successfully copied over all of the data
151 	 * from the user.
152 	 */
153 	if (kcmlen > stackbuf_size)
154 		kcmsg_base = kcmsg = sock_kmalloc(sk, kcmlen, GFP_KERNEL);
155 	if (kcmsg == NULL)
156 		return -ENOBUFS;
157 
158 	/* Now copy them over neatly. */
159 	memset(kcmsg, 0, kcmlen);
160 	ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
161 	while (ucmsg != NULL) {
162 		if (__get_user(ucmlen, &ucmsg->cmsg_len))
163 			goto Efault;
164 		if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
165 			goto Einval;
166 		tmp = ((ucmlen - CMSG_COMPAT_ALIGN(sizeof(*ucmsg))) +
167 		       CMSG_ALIGN(sizeof(struct cmsghdr)));
168 		if ((char *)kcmsg_base + kcmlen - (char *)kcmsg < CMSG_ALIGN(tmp))
169 			goto Einval;
170 		kcmsg->cmsg_len = tmp;
171 		tmp = CMSG_ALIGN(tmp);
172 		if (__get_user(kcmsg->cmsg_level, &ucmsg->cmsg_level) ||
173 		    __get_user(kcmsg->cmsg_type, &ucmsg->cmsg_type) ||
174 		    copy_from_user(CMSG_DATA(kcmsg),
175 				   CMSG_COMPAT_DATA(ucmsg),
176 				   (ucmlen - CMSG_COMPAT_ALIGN(sizeof(*ucmsg)))))
177 			goto Efault;
178 
179 		/* Advance. */
180 		kcmsg = (struct cmsghdr *)((char *)kcmsg + tmp);
181 		ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
182 	}
183 
184 	/* Ok, looks like we made it.  Hook it up and return success. */
185 	kmsg->msg_control = kcmsg_base;
186 	kmsg->msg_controllen = kcmlen;
187 	return 0;
188 
189 Einval:
190 	err = -EINVAL;
191 Efault:
192 	if (kcmsg_base != (struct cmsghdr *)stackbuf)
193 		sock_kfree_s(sk, kcmsg_base, kcmlen);
194 	return err;
195 }
196 
197 int put_cmsg_compat(struct msghdr *kmsg, int level, int type, int len, void *data)
198 {
199 	struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
200 	struct compat_cmsghdr cmhdr;
201 	struct compat_timeval ctv;
202 	struct compat_timespec cts[3];
203 	int cmlen;
204 
205 	if (cm == NULL || kmsg->msg_controllen < sizeof(*cm)) {
206 		kmsg->msg_flags |= MSG_CTRUNC;
207 		return 0; /* XXX: return error? check spec. */
208 	}
209 
210 	if (!COMPAT_USE_64BIT_TIME) {
211 		if (level == SOL_SOCKET && type == SCM_TIMESTAMP) {
212 			struct timeval *tv = (struct timeval *)data;
213 			ctv.tv_sec = tv->tv_sec;
214 			ctv.tv_usec = tv->tv_usec;
215 			data = &ctv;
216 			len = sizeof(ctv);
217 		}
218 		if (level == SOL_SOCKET &&
219 		    (type == SCM_TIMESTAMPNS || type == SCM_TIMESTAMPING)) {
220 			int count = type == SCM_TIMESTAMPNS ? 1 : 3;
221 			int i;
222 			struct timespec *ts = (struct timespec *)data;
223 			for (i = 0; i < count; i++) {
224 				cts[i].tv_sec = ts[i].tv_sec;
225 				cts[i].tv_nsec = ts[i].tv_nsec;
226 			}
227 			data = &cts;
228 			len = sizeof(cts[0]) * count;
229 		}
230 	}
231 
232 	cmlen = CMSG_COMPAT_LEN(len);
233 	if (kmsg->msg_controllen < cmlen) {
234 		kmsg->msg_flags |= MSG_CTRUNC;
235 		cmlen = kmsg->msg_controllen;
236 	}
237 	cmhdr.cmsg_level = level;
238 	cmhdr.cmsg_type = type;
239 	cmhdr.cmsg_len = cmlen;
240 
241 	if (copy_to_user(cm, &cmhdr, sizeof cmhdr))
242 		return -EFAULT;
243 	if (copy_to_user(CMSG_COMPAT_DATA(cm), data, cmlen - sizeof(struct compat_cmsghdr)))
244 		return -EFAULT;
245 	cmlen = CMSG_COMPAT_SPACE(len);
246 	if (kmsg->msg_controllen < cmlen)
247 		cmlen = kmsg->msg_controllen;
248 	kmsg->msg_control += cmlen;
249 	kmsg->msg_controllen -= cmlen;
250 	return 0;
251 }
252 
253 void scm_detach_fds_compat(struct msghdr *kmsg, struct scm_cookie *scm)
254 {
255 	struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
256 	int fdmax = (kmsg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int);
257 	int fdnum = scm->fp->count;
258 	struct file **fp = scm->fp->fp;
259 	int __user *cmfptr;
260 	int err = 0, i;
261 
262 	if (fdnum < fdmax)
263 		fdmax = fdnum;
264 
265 	for (i = 0, cmfptr = (int __user *) CMSG_COMPAT_DATA(cm); i < fdmax; i++, cmfptr++) {
266 		int new_fd;
267 		err = security_file_receive(fp[i]);
268 		if (err)
269 			break;
270 		err = get_unused_fd_flags(MSG_CMSG_CLOEXEC & kmsg->msg_flags
271 					  ? O_CLOEXEC : 0);
272 		if (err < 0)
273 			break;
274 		new_fd = err;
275 		err = put_user(new_fd, cmfptr);
276 		if (err) {
277 			put_unused_fd(new_fd);
278 			break;
279 		}
280 		/* Bump the usage count and install the file. */
281 		fd_install(new_fd, get_file(fp[i]));
282 	}
283 
284 	if (i > 0) {
285 		int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
286 		err = put_user(SOL_SOCKET, &cm->cmsg_level);
287 		if (!err)
288 			err = put_user(SCM_RIGHTS, &cm->cmsg_type);
289 		if (!err)
290 			err = put_user(cmlen, &cm->cmsg_len);
291 		if (!err) {
292 			cmlen = CMSG_COMPAT_SPACE(i * sizeof(int));
293 			kmsg->msg_control += cmlen;
294 			kmsg->msg_controllen -= cmlen;
295 		}
296 	}
297 	if (i < fdnum)
298 		kmsg->msg_flags |= MSG_CTRUNC;
299 
300 	/*
301 	 * All of the files that fit in the message have had their
302 	 * usage counts incremented, so we just free the list.
303 	 */
304 	__scm_destroy(scm);
305 }
306 
307 static int do_set_attach_filter(struct socket *sock, int level, int optname,
308 				char __user *optval, unsigned int optlen)
309 {
310 	struct compat_sock_fprog __user *fprog32 = (struct compat_sock_fprog __user *)optval;
311 	struct sock_fprog __user *kfprog = compat_alloc_user_space(sizeof(struct sock_fprog));
312 	compat_uptr_t ptr;
313 	u16 len;
314 
315 	if (!access_ok(VERIFY_READ, fprog32, sizeof(*fprog32)) ||
316 	    !access_ok(VERIFY_WRITE, kfprog, sizeof(struct sock_fprog)) ||
317 	    __get_user(len, &fprog32->len) ||
318 	    __get_user(ptr, &fprog32->filter) ||
319 	    __put_user(len, &kfprog->len) ||
320 	    __put_user(compat_ptr(ptr), &kfprog->filter))
321 		return -EFAULT;
322 
323 	return sock_setsockopt(sock, level, optname, (char __user *)kfprog,
324 			      sizeof(struct sock_fprog));
325 }
326 
327 static int do_set_sock_timeout(struct socket *sock, int level,
328 		int optname, char __user *optval, unsigned int optlen)
329 {
330 	struct compat_timeval __user *up = (struct compat_timeval __user *)optval;
331 	struct timeval ktime;
332 	mm_segment_t old_fs;
333 	int err;
334 
335 	if (optlen < sizeof(*up))
336 		return -EINVAL;
337 	if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
338 	    __get_user(ktime.tv_sec, &up->tv_sec) ||
339 	    __get_user(ktime.tv_usec, &up->tv_usec))
340 		return -EFAULT;
341 	old_fs = get_fs();
342 	set_fs(KERNEL_DS);
343 	err = sock_setsockopt(sock, level, optname, (char *)&ktime, sizeof(ktime));
344 	set_fs(old_fs);
345 
346 	return err;
347 }
348 
349 static int compat_sock_setsockopt(struct socket *sock, int level, int optname,
350 				char __user *optval, unsigned int optlen)
351 {
352 	if (optname == SO_ATTACH_FILTER)
353 		return do_set_attach_filter(sock, level, optname,
354 					    optval, optlen);
355 	if (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO)
356 		return do_set_sock_timeout(sock, level, optname, optval, optlen);
357 
358 	return sock_setsockopt(sock, level, optname, optval, optlen);
359 }
360 
361 COMPAT_SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
362 		       char __user *, optval, unsigned int, optlen)
363 {
364 	int err;
365 	struct socket *sock = sockfd_lookup(fd, &err);
366 
367 	if (sock) {
368 		err = security_socket_setsockopt(sock, level, optname);
369 		if (err) {
370 			sockfd_put(sock);
371 			return err;
372 		}
373 
374 		if (level == SOL_SOCKET)
375 			err = compat_sock_setsockopt(sock, level,
376 					optname, optval, optlen);
377 		else if (sock->ops->compat_setsockopt)
378 			err = sock->ops->compat_setsockopt(sock, level,
379 					optname, optval, optlen);
380 		else
381 			err = sock->ops->setsockopt(sock, level,
382 					optname, optval, optlen);
383 		sockfd_put(sock);
384 	}
385 	return err;
386 }
387 
388 static int do_get_sock_timeout(struct socket *sock, int level, int optname,
389 		char __user *optval, int __user *optlen)
390 {
391 	struct compat_timeval __user *up;
392 	struct timeval ktime;
393 	mm_segment_t old_fs;
394 	int len, err;
395 
396 	up = (struct compat_timeval __user *) optval;
397 	if (get_user(len, optlen))
398 		return -EFAULT;
399 	if (len < sizeof(*up))
400 		return -EINVAL;
401 	len = sizeof(ktime);
402 	old_fs = get_fs();
403 	set_fs(KERNEL_DS);
404 	err = sock_getsockopt(sock, level, optname, (char *) &ktime, &len);
405 	set_fs(old_fs);
406 
407 	if (!err) {
408 		if (put_user(sizeof(*up), optlen) ||
409 		    !access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
410 		    __put_user(ktime.tv_sec, &up->tv_sec) ||
411 		    __put_user(ktime.tv_usec, &up->tv_usec))
412 			err = -EFAULT;
413 	}
414 	return err;
415 }
416 
417 static int compat_sock_getsockopt(struct socket *sock, int level, int optname,
418 				char __user *optval, int __user *optlen)
419 {
420 	if (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO)
421 		return do_get_sock_timeout(sock, level, optname, optval, optlen);
422 	return sock_getsockopt(sock, level, optname, optval, optlen);
423 }
424 
425 int compat_sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
426 {
427 	struct compat_timeval __user *ctv;
428 	int err;
429 	struct timeval tv;
430 
431 	if (COMPAT_USE_64BIT_TIME)
432 		return sock_get_timestamp(sk, userstamp);
433 
434 	ctv = (struct compat_timeval __user *) userstamp;
435 	err = -ENOENT;
436 	if (!sock_flag(sk, SOCK_TIMESTAMP))
437 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
438 	tv = ktime_to_timeval(sk->sk_stamp);
439 	if (tv.tv_sec == -1)
440 		return err;
441 	if (tv.tv_sec == 0) {
442 		sk->sk_stamp = ktime_get_real();
443 		tv = ktime_to_timeval(sk->sk_stamp);
444 	}
445 	err = 0;
446 	if (put_user(tv.tv_sec, &ctv->tv_sec) ||
447 			put_user(tv.tv_usec, &ctv->tv_usec))
448 		err = -EFAULT;
449 	return err;
450 }
451 EXPORT_SYMBOL(compat_sock_get_timestamp);
452 
453 int compat_sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
454 {
455 	struct compat_timespec __user *ctv;
456 	int err;
457 	struct timespec ts;
458 
459 	if (COMPAT_USE_64BIT_TIME)
460 		return sock_get_timestampns (sk, userstamp);
461 
462 	ctv = (struct compat_timespec __user *) userstamp;
463 	err = -ENOENT;
464 	if (!sock_flag(sk, SOCK_TIMESTAMP))
465 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
466 	ts = ktime_to_timespec(sk->sk_stamp);
467 	if (ts.tv_sec == -1)
468 		return err;
469 	if (ts.tv_sec == 0) {
470 		sk->sk_stamp = ktime_get_real();
471 		ts = ktime_to_timespec(sk->sk_stamp);
472 	}
473 	err = 0;
474 	if (put_user(ts.tv_sec, &ctv->tv_sec) ||
475 			put_user(ts.tv_nsec, &ctv->tv_nsec))
476 		err = -EFAULT;
477 	return err;
478 }
479 EXPORT_SYMBOL(compat_sock_get_timestampns);
480 
481 COMPAT_SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname,
482 		       char __user *, optval, int __user *, optlen)
483 {
484 	int err;
485 	struct socket *sock = sockfd_lookup(fd, &err);
486 
487 	if (sock) {
488 		err = security_socket_getsockopt(sock, level, optname);
489 		if (err) {
490 			sockfd_put(sock);
491 			return err;
492 		}
493 
494 		if (level == SOL_SOCKET)
495 			err = compat_sock_getsockopt(sock, level,
496 					optname, optval, optlen);
497 		else if (sock->ops->compat_getsockopt)
498 			err = sock->ops->compat_getsockopt(sock, level,
499 					optname, optval, optlen);
500 		else
501 			err = sock->ops->getsockopt(sock, level,
502 					optname, optval, optlen);
503 		sockfd_put(sock);
504 	}
505 	return err;
506 }
507 
508 struct compat_group_req {
509 	__u32				 gr_interface;
510 	struct __kernel_sockaddr_storage gr_group
511 		__attribute__ ((aligned(4)));
512 } __packed;
513 
514 struct compat_group_source_req {
515 	__u32				 gsr_interface;
516 	struct __kernel_sockaddr_storage gsr_group
517 		__attribute__ ((aligned(4)));
518 	struct __kernel_sockaddr_storage gsr_source
519 		__attribute__ ((aligned(4)));
520 } __packed;
521 
522 struct compat_group_filter {
523 	__u32				 gf_interface;
524 	struct __kernel_sockaddr_storage gf_group
525 		__attribute__ ((aligned(4)));
526 	__u32				 gf_fmode;
527 	__u32				 gf_numsrc;
528 	struct __kernel_sockaddr_storage gf_slist[1]
529 		__attribute__ ((aligned(4)));
530 } __packed;
531 
532 #define __COMPAT_GF0_SIZE (sizeof(struct compat_group_filter) - \
533 			sizeof(struct __kernel_sockaddr_storage))
534 
535 
536 int compat_mc_setsockopt(struct sock *sock, int level, int optname,
537 	char __user *optval, unsigned int optlen,
538 	int (*setsockopt)(struct sock *, int, int, char __user *, unsigned int))
539 {
540 	char __user	*koptval = optval;
541 	int		koptlen = optlen;
542 
543 	switch (optname) {
544 	case MCAST_JOIN_GROUP:
545 	case MCAST_LEAVE_GROUP:
546 	{
547 		struct compat_group_req __user *gr32 = (void *)optval;
548 		struct group_req __user *kgr =
549 			compat_alloc_user_space(sizeof(struct group_req));
550 		u32 interface;
551 
552 		if (!access_ok(VERIFY_READ, gr32, sizeof(*gr32)) ||
553 		    !access_ok(VERIFY_WRITE, kgr, sizeof(struct group_req)) ||
554 		    __get_user(interface, &gr32->gr_interface) ||
555 		    __put_user(interface, &kgr->gr_interface) ||
556 		    copy_in_user(&kgr->gr_group, &gr32->gr_group,
557 				sizeof(kgr->gr_group)))
558 			return -EFAULT;
559 		koptval = (char __user *)kgr;
560 		koptlen = sizeof(struct group_req);
561 		break;
562 	}
563 	case MCAST_JOIN_SOURCE_GROUP:
564 	case MCAST_LEAVE_SOURCE_GROUP:
565 	case MCAST_BLOCK_SOURCE:
566 	case MCAST_UNBLOCK_SOURCE:
567 	{
568 		struct compat_group_source_req __user *gsr32 = (void *)optval;
569 		struct group_source_req __user *kgsr = compat_alloc_user_space(
570 			sizeof(struct group_source_req));
571 		u32 interface;
572 
573 		if (!access_ok(VERIFY_READ, gsr32, sizeof(*gsr32)) ||
574 		    !access_ok(VERIFY_WRITE, kgsr,
575 			sizeof(struct group_source_req)) ||
576 		    __get_user(interface, &gsr32->gsr_interface) ||
577 		    __put_user(interface, &kgsr->gsr_interface) ||
578 		    copy_in_user(&kgsr->gsr_group, &gsr32->gsr_group,
579 				sizeof(kgsr->gsr_group)) ||
580 		    copy_in_user(&kgsr->gsr_source, &gsr32->gsr_source,
581 				sizeof(kgsr->gsr_source)))
582 			return -EFAULT;
583 		koptval = (char __user *)kgsr;
584 		koptlen = sizeof(struct group_source_req);
585 		break;
586 	}
587 	case MCAST_MSFILTER:
588 	{
589 		struct compat_group_filter __user *gf32 = (void *)optval;
590 		struct group_filter __user *kgf;
591 		u32 interface, fmode, numsrc;
592 
593 		if (!access_ok(VERIFY_READ, gf32, __COMPAT_GF0_SIZE) ||
594 		    __get_user(interface, &gf32->gf_interface) ||
595 		    __get_user(fmode, &gf32->gf_fmode) ||
596 		    __get_user(numsrc, &gf32->gf_numsrc))
597 			return -EFAULT;
598 		koptlen = optlen + sizeof(struct group_filter) -
599 				sizeof(struct compat_group_filter);
600 		if (koptlen < GROUP_FILTER_SIZE(numsrc))
601 			return -EINVAL;
602 		kgf = compat_alloc_user_space(koptlen);
603 		if (!access_ok(VERIFY_WRITE, kgf, koptlen) ||
604 		    __put_user(interface, &kgf->gf_interface) ||
605 		    __put_user(fmode, &kgf->gf_fmode) ||
606 		    __put_user(numsrc, &kgf->gf_numsrc) ||
607 		    copy_in_user(&kgf->gf_group, &gf32->gf_group,
608 				sizeof(kgf->gf_group)) ||
609 		    (numsrc && copy_in_user(kgf->gf_slist, gf32->gf_slist,
610 				numsrc * sizeof(kgf->gf_slist[0]))))
611 			return -EFAULT;
612 		koptval = (char __user *)kgf;
613 		break;
614 	}
615 
616 	default:
617 		break;
618 	}
619 	return setsockopt(sock, level, optname, koptval, koptlen);
620 }
621 EXPORT_SYMBOL(compat_mc_setsockopt);
622 
623 int compat_mc_getsockopt(struct sock *sock, int level, int optname,
624 	char __user *optval, int __user *optlen,
625 	int (*getsockopt)(struct sock *, int, int, char __user *, int __user *))
626 {
627 	struct compat_group_filter __user *gf32 = (void *)optval;
628 	struct group_filter __user *kgf;
629 	int __user	*koptlen;
630 	u32 interface, fmode, numsrc;
631 	int klen, ulen, err;
632 
633 	if (optname != MCAST_MSFILTER)
634 		return getsockopt(sock, level, optname, optval, optlen);
635 
636 	koptlen = compat_alloc_user_space(sizeof(*koptlen));
637 	if (!access_ok(VERIFY_READ, optlen, sizeof(*optlen)) ||
638 	    __get_user(ulen, optlen))
639 		return -EFAULT;
640 
641 	/* adjust len for pad */
642 	klen = ulen + sizeof(*kgf) - sizeof(*gf32);
643 
644 	if (klen < GROUP_FILTER_SIZE(0))
645 		return -EINVAL;
646 
647 	if (!access_ok(VERIFY_WRITE, koptlen, sizeof(*koptlen)) ||
648 	    __put_user(klen, koptlen))
649 		return -EFAULT;
650 
651 	/* have to allow space for previous compat_alloc_user_space, too */
652 	kgf = compat_alloc_user_space(klen+sizeof(*optlen));
653 
654 	if (!access_ok(VERIFY_READ, gf32, __COMPAT_GF0_SIZE) ||
655 	    __get_user(interface, &gf32->gf_interface) ||
656 	    __get_user(fmode, &gf32->gf_fmode) ||
657 	    __get_user(numsrc, &gf32->gf_numsrc) ||
658 	    __put_user(interface, &kgf->gf_interface) ||
659 	    __put_user(fmode, &kgf->gf_fmode) ||
660 	    __put_user(numsrc, &kgf->gf_numsrc) ||
661 	    copy_in_user(&kgf->gf_group, &gf32->gf_group, sizeof(kgf->gf_group)))
662 		return -EFAULT;
663 
664 	err = getsockopt(sock, level, optname, (char __user *)kgf, koptlen);
665 	if (err)
666 		return err;
667 
668 	if (!access_ok(VERIFY_READ, koptlen, sizeof(*koptlen)) ||
669 	    __get_user(klen, koptlen))
670 		return -EFAULT;
671 
672 	ulen = klen - (sizeof(*kgf)-sizeof(*gf32));
673 
674 	if (!access_ok(VERIFY_WRITE, optlen, sizeof(*optlen)) ||
675 	    __put_user(ulen, optlen))
676 		return -EFAULT;
677 
678 	if (!access_ok(VERIFY_READ, kgf, klen) ||
679 	    !access_ok(VERIFY_WRITE, gf32, ulen) ||
680 	    __get_user(interface, &kgf->gf_interface) ||
681 	    __get_user(fmode, &kgf->gf_fmode) ||
682 	    __get_user(numsrc, &kgf->gf_numsrc) ||
683 	    __put_user(interface, &gf32->gf_interface) ||
684 	    __put_user(fmode, &gf32->gf_fmode) ||
685 	    __put_user(numsrc, &gf32->gf_numsrc))
686 		return -EFAULT;
687 	if (numsrc) {
688 		int copylen;
689 
690 		klen -= GROUP_FILTER_SIZE(0);
691 		copylen = numsrc * sizeof(gf32->gf_slist[0]);
692 		if (copylen > klen)
693 			copylen = klen;
694 		if (copy_in_user(gf32->gf_slist, kgf->gf_slist, copylen))
695 			return -EFAULT;
696 	}
697 	return err;
698 }
699 EXPORT_SYMBOL(compat_mc_getsockopt);
700 
701 
702 /* Argument list sizes for compat_sys_socketcall */
703 #define AL(x) ((x) * sizeof(u32))
704 static unsigned char nas[21] = {
705 	AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
706 	AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
707 	AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
708 	AL(4), AL(5), AL(4)
709 };
710 #undef AL
711 
712 COMPAT_SYSCALL_DEFINE3(sendmsg, int, fd, struct compat_msghdr __user *, msg, unsigned int, flags)
713 {
714 	if (flags & MSG_CMSG_COMPAT)
715 		return -EINVAL;
716 	return __sys_sendmsg(fd, (struct user_msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
717 }
718 
719 COMPAT_SYSCALL_DEFINE4(sendmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
720 		       unsigned int, vlen, unsigned int, flags)
721 {
722 	if (flags & MSG_CMSG_COMPAT)
723 		return -EINVAL;
724 	return __sys_sendmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
725 			      flags | MSG_CMSG_COMPAT);
726 }
727 
728 COMPAT_SYSCALL_DEFINE3(recvmsg, int, fd, struct compat_msghdr __user *, msg, unsigned int, flags)
729 {
730 	if (flags & MSG_CMSG_COMPAT)
731 		return -EINVAL;
732 	return __sys_recvmsg(fd, (struct user_msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
733 }
734 
735 COMPAT_SYSCALL_DEFINE4(recv, int, fd, void __user *, buf, compat_size_t, len, unsigned int, flags)
736 {
737 	return sys_recv(fd, buf, len, flags | MSG_CMSG_COMPAT);
738 }
739 
740 COMPAT_SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, buf, compat_size_t, len,
741 		       unsigned int, flags, struct sockaddr __user *, addr,
742 		       int __user *, addrlen)
743 {
744 	return sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr, addrlen);
745 }
746 
747 COMPAT_SYSCALL_DEFINE5(recvmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
748 		       unsigned int, vlen, unsigned int, flags,
749 		       struct compat_timespec __user *, timeout)
750 {
751 	int datagrams;
752 	struct timespec ktspec;
753 
754 	if (flags & MSG_CMSG_COMPAT)
755 		return -EINVAL;
756 
757 	if (timeout == NULL)
758 		return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
759 				      flags | MSG_CMSG_COMPAT, NULL);
760 
761 	if (compat_get_timespec(&ktspec, timeout))
762 		return -EFAULT;
763 
764 	datagrams = __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
765 				   flags | MSG_CMSG_COMPAT, &ktspec);
766 	if (datagrams > 0 && compat_put_timespec(&ktspec, timeout))
767 		datagrams = -EFAULT;
768 
769 	return datagrams;
770 }
771 
772 COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args)
773 {
774 	int ret;
775 	u32 a[6];
776 	u32 a0, a1;
777 
778 	if (call < SYS_SOCKET || call > SYS_SENDMMSG)
779 		return -EINVAL;
780 	if (copy_from_user(a, args, nas[call]))
781 		return -EFAULT;
782 	a0 = a[0];
783 	a1 = a[1];
784 
785 	switch (call) {
786 	case SYS_SOCKET:
787 		ret = sys_socket(a0, a1, a[2]);
788 		break;
789 	case SYS_BIND:
790 		ret = sys_bind(a0, compat_ptr(a1), a[2]);
791 		break;
792 	case SYS_CONNECT:
793 		ret = sys_connect(a0, compat_ptr(a1), a[2]);
794 		break;
795 	case SYS_LISTEN:
796 		ret = sys_listen(a0, a1);
797 		break;
798 	case SYS_ACCEPT:
799 		ret = sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0);
800 		break;
801 	case SYS_GETSOCKNAME:
802 		ret = sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]));
803 		break;
804 	case SYS_GETPEERNAME:
805 		ret = sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2]));
806 		break;
807 	case SYS_SOCKETPAIR:
808 		ret = sys_socketpair(a0, a1, a[2], compat_ptr(a[3]));
809 		break;
810 	case SYS_SEND:
811 		ret = sys_send(a0, compat_ptr(a1), a[2], a[3]);
812 		break;
813 	case SYS_SENDTO:
814 		ret = sys_sendto(a0, compat_ptr(a1), a[2], a[3], compat_ptr(a[4]), a[5]);
815 		break;
816 	case SYS_RECV:
817 		ret = compat_sys_recv(a0, compat_ptr(a1), a[2], a[3]);
818 		break;
819 	case SYS_RECVFROM:
820 		ret = compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
821 					  compat_ptr(a[4]), compat_ptr(a[5]));
822 		break;
823 	case SYS_SHUTDOWN:
824 		ret = sys_shutdown(a0, a1);
825 		break;
826 	case SYS_SETSOCKOPT:
827 		ret = compat_sys_setsockopt(a0, a1, a[2],
828 				compat_ptr(a[3]), a[4]);
829 		break;
830 	case SYS_GETSOCKOPT:
831 		ret = compat_sys_getsockopt(a0, a1, a[2],
832 				compat_ptr(a[3]), compat_ptr(a[4]));
833 		break;
834 	case SYS_SENDMSG:
835 		ret = compat_sys_sendmsg(a0, compat_ptr(a1), a[2]);
836 		break;
837 	case SYS_SENDMMSG:
838 		ret = compat_sys_sendmmsg(a0, compat_ptr(a1), a[2], a[3]);
839 		break;
840 	case SYS_RECVMSG:
841 		ret = compat_sys_recvmsg(a0, compat_ptr(a1), a[2]);
842 		break;
843 	case SYS_RECVMMSG:
844 		ret = compat_sys_recvmmsg(a0, compat_ptr(a1), a[2], a[3],
845 					  compat_ptr(a[4]));
846 		break;
847 	case SYS_ACCEPT4:
848 		ret = sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]);
849 		break;
850 	default:
851 		ret = -EINVAL;
852 		break;
853 	}
854 	return ret;
855 }
856