xref: /linux/net/compat.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
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 
26 #include <net/scm.h>
27 #include <net/sock.h>
28 #include <net/ip.h>
29 #include <net/ipv6.h>
30 #include <asm/uaccess.h>
31 #include <net/compat.h>
32 
33 static inline int iov_from_user_compat_to_kern(struct iovec *kiov,
34 					  struct compat_iovec __user *uiov32,
35 					  int niov)
36 {
37 	int tot_len = 0;
38 
39 	while (niov > 0) {
40 		compat_uptr_t buf;
41 		compat_size_t len;
42 
43 		if (get_user(len, &uiov32->iov_len) ||
44 		   get_user(buf, &uiov32->iov_base)) {
45 			tot_len = -EFAULT;
46 			break;
47 		}
48 		tot_len += len;
49 		kiov->iov_base = compat_ptr(buf);
50 		kiov->iov_len = (__kernel_size_t) len;
51 		uiov32++;
52 		kiov++;
53 		niov--;
54 	}
55 	return tot_len;
56 }
57 
58 int get_compat_msghdr(struct msghdr *kmsg, struct compat_msghdr __user *umsg)
59 {
60 	compat_uptr_t tmp1, tmp2, tmp3;
61 
62 	if (!access_ok(VERIFY_READ, umsg, sizeof(*umsg)) ||
63 	    __get_user(tmp1, &umsg->msg_name) ||
64 	    __get_user(kmsg->msg_namelen, &umsg->msg_namelen) ||
65 	    __get_user(tmp2, &umsg->msg_iov) ||
66 	    __get_user(kmsg->msg_iovlen, &umsg->msg_iovlen) ||
67 	    __get_user(tmp3, &umsg->msg_control) ||
68 	    __get_user(kmsg->msg_controllen, &umsg->msg_controllen) ||
69 	    __get_user(kmsg->msg_flags, &umsg->msg_flags))
70 		return -EFAULT;
71 	kmsg->msg_name = compat_ptr(tmp1);
72 	kmsg->msg_iov = compat_ptr(tmp2);
73 	kmsg->msg_control = compat_ptr(tmp3);
74 	return 0;
75 }
76 
77 /* I've named the args so it is easy to tell whose space the pointers are in. */
78 int verify_compat_iovec(struct msghdr *kern_msg, struct iovec *kern_iov,
79 		   struct sockaddr *kern_address, int mode)
80 {
81 	int tot_len;
82 
83 	if (kern_msg->msg_namelen) {
84 		if (mode == VERIFY_READ) {
85 			int err = move_addr_to_kernel(kern_msg->msg_name,
86 						      kern_msg->msg_namelen,
87 						      kern_address);
88 			if (err < 0)
89 				return err;
90 		}
91 		kern_msg->msg_name = kern_address;
92 	} else
93 		kern_msg->msg_name = NULL;
94 
95 	tot_len = iov_from_user_compat_to_kern(kern_iov,
96 					  (struct compat_iovec __user *)kern_msg->msg_iov,
97 					  kern_msg->msg_iovlen);
98 	if (tot_len >= 0)
99 		kern_msg->msg_iov = kern_iov;
100 
101 	return tot_len;
102 }
103 
104 /* Bleech... */
105 #define CMSG_COMPAT_ALIGN(len)	ALIGN((len), sizeof(s32))
106 
107 #define CMSG_COMPAT_DATA(cmsg)				\
108 	((void __user *)((char __user *)(cmsg) + CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr))))
109 #define CMSG_COMPAT_SPACE(len)				\
110 	(CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)) + CMSG_COMPAT_ALIGN(len))
111 #define CMSG_COMPAT_LEN(len)				\
112 	(CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)) + (len))
113 
114 #define CMSG_COMPAT_FIRSTHDR(msg)			\
115 	(((msg)->msg_controllen) >= sizeof(struct compat_cmsghdr) ?	\
116 	 (struct compat_cmsghdr __user *)((msg)->msg_control) :		\
117 	 (struct compat_cmsghdr __user *)NULL)
118 
119 #define CMSG_COMPAT_OK(ucmlen, ucmsg, mhdr) \
120 	((ucmlen) >= sizeof(struct compat_cmsghdr) && \
121 	 (ucmlen) <= (unsigned long) \
122 	 ((mhdr)->msg_controllen - \
123 	  ((char *)(ucmsg) - (char *)(mhdr)->msg_control)))
124 
125 static inline struct compat_cmsghdr __user *cmsg_compat_nxthdr(struct msghdr *msg,
126 		struct compat_cmsghdr __user *cmsg, int cmsg_len)
127 {
128 	char __user *ptr = (char __user *)cmsg + CMSG_COMPAT_ALIGN(cmsg_len);
129 	if ((unsigned long)(ptr + 1 - (char __user *)msg->msg_control) >
130 			msg->msg_controllen)
131 		return NULL;
132 	return (struct compat_cmsghdr __user *)ptr;
133 }
134 
135 /* There is a lot of hair here because the alignment rules (and
136  * thus placement) of cmsg headers and length are different for
137  * 32-bit apps.  -DaveM
138  */
139 int cmsghdr_from_user_compat_to_kern(struct msghdr *kmsg, struct sock *sk,
140 			       unsigned char *stackbuf, int stackbuf_size)
141 {
142 	struct compat_cmsghdr __user *ucmsg;
143 	struct cmsghdr *kcmsg, *kcmsg_base;
144 	compat_size_t ucmlen;
145 	__kernel_size_t kcmlen, tmp;
146 	int err = -EFAULT;
147 
148 	kcmlen = 0;
149 	kcmsg_base = kcmsg = (struct cmsghdr *)stackbuf;
150 	ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
151 	while (ucmsg != NULL) {
152 		if (get_user(ucmlen, &ucmsg->cmsg_len))
153 			return -EFAULT;
154 
155 		/* Catch bogons. */
156 		if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
157 			return -EINVAL;
158 
159 		tmp = ((ucmlen - CMSG_COMPAT_ALIGN(sizeof(*ucmsg))) +
160 		       CMSG_ALIGN(sizeof(struct cmsghdr)));
161 		tmp = CMSG_ALIGN(tmp);
162 		kcmlen += tmp;
163 		ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
164 	}
165 	if (kcmlen == 0)
166 		return -EINVAL;
167 
168 	/* The kcmlen holds the 64-bit version of the control length.
169 	 * It may not be modified as we do not stick it into the kmsg
170 	 * until we have successfully copied over all of the data
171 	 * from the user.
172 	 */
173 	if (kcmlen > stackbuf_size)
174 		kcmsg_base = kcmsg = sock_kmalloc(sk, kcmlen, GFP_KERNEL);
175 	if (kcmsg == NULL)
176 		return -ENOBUFS;
177 
178 	/* Now copy them over neatly. */
179 	memset(kcmsg, 0, kcmlen);
180 	ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
181 	while (ucmsg != NULL) {
182 		if (__get_user(ucmlen, &ucmsg->cmsg_len))
183 			goto Efault;
184 		if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
185 			goto Einval;
186 		tmp = ((ucmlen - CMSG_COMPAT_ALIGN(sizeof(*ucmsg))) +
187 		       CMSG_ALIGN(sizeof(struct cmsghdr)));
188 		if ((char *)kcmsg_base + kcmlen - (char *)kcmsg < CMSG_ALIGN(tmp))
189 			goto Einval;
190 		kcmsg->cmsg_len = tmp;
191 		tmp = CMSG_ALIGN(tmp);
192 		if (__get_user(kcmsg->cmsg_level, &ucmsg->cmsg_level) ||
193 		    __get_user(kcmsg->cmsg_type, &ucmsg->cmsg_type) ||
194 		    copy_from_user(CMSG_DATA(kcmsg),
195 				   CMSG_COMPAT_DATA(ucmsg),
196 				   (ucmlen - CMSG_COMPAT_ALIGN(sizeof(*ucmsg)))))
197 			goto Efault;
198 
199 		/* Advance. */
200 		kcmsg = (struct cmsghdr *)((char *)kcmsg + tmp);
201 		ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
202 	}
203 
204 	/* Ok, looks like we made it.  Hook it up and return success. */
205 	kmsg->msg_control = kcmsg_base;
206 	kmsg->msg_controllen = kcmlen;
207 	return 0;
208 
209 Einval:
210 	err = -EINVAL;
211 Efault:
212 	if (kcmsg_base != (struct cmsghdr *)stackbuf)
213 		sock_kfree_s(sk, kcmsg_base, kcmlen);
214 	return err;
215 }
216 
217 int put_cmsg_compat(struct msghdr *kmsg, int level, int type, int len, void *data)
218 {
219 	struct compat_timeval ctv;
220 	struct compat_timespec cts[3];
221 	struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
222 	struct compat_cmsghdr cmhdr;
223 	int cmlen;
224 
225 	if (cm == NULL || kmsg->msg_controllen < sizeof(*cm)) {
226 		kmsg->msg_flags |= MSG_CTRUNC;
227 		return 0; /* XXX: return error? check spec. */
228 	}
229 
230 	if (level == SOL_SOCKET && type == SCM_TIMESTAMP) {
231 		struct timeval *tv = (struct timeval *)data;
232 		ctv.tv_sec = tv->tv_sec;
233 		ctv.tv_usec = tv->tv_usec;
234 		data = &ctv;
235 		len = sizeof(ctv);
236 	}
237 	if (level == SOL_SOCKET &&
238 	    (type == SCM_TIMESTAMPNS || type == SCM_TIMESTAMPING)) {
239 		int count = type == SCM_TIMESTAMPNS ? 1 : 3;
240 		int i;
241 		struct timespec *ts = (struct timespec *)data;
242 		for (i = 0; i < count; i++) {
243 			cts[i].tv_sec = ts[i].tv_sec;
244 			cts[i].tv_nsec = ts[i].tv_nsec;
245 		}
246 		data = &cts;
247 		len = sizeof(cts[0]) * count;
248 	}
249 
250 	cmlen = CMSG_COMPAT_LEN(len);
251 	if (kmsg->msg_controllen < cmlen) {
252 		kmsg->msg_flags |= MSG_CTRUNC;
253 		cmlen = kmsg->msg_controllen;
254 	}
255 	cmhdr.cmsg_level = level;
256 	cmhdr.cmsg_type = type;
257 	cmhdr.cmsg_len = cmlen;
258 
259 	if (copy_to_user(cm, &cmhdr, sizeof cmhdr))
260 		return -EFAULT;
261 	if (copy_to_user(CMSG_COMPAT_DATA(cm), data, cmlen - sizeof(struct compat_cmsghdr)))
262 		return -EFAULT;
263 	cmlen = CMSG_COMPAT_SPACE(len);
264 	if (kmsg->msg_controllen < cmlen)
265 		cmlen = kmsg->msg_controllen;
266 	kmsg->msg_control += cmlen;
267 	kmsg->msg_controllen -= cmlen;
268 	return 0;
269 }
270 
271 void scm_detach_fds_compat(struct msghdr *kmsg, struct scm_cookie *scm)
272 {
273 	struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
274 	int fdmax = (kmsg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int);
275 	int fdnum = scm->fp->count;
276 	struct file **fp = scm->fp->fp;
277 	int __user *cmfptr;
278 	int err = 0, i;
279 
280 	if (fdnum < fdmax)
281 		fdmax = fdnum;
282 
283 	for (i = 0, cmfptr = (int __user *) CMSG_COMPAT_DATA(cm); i < fdmax; i++, cmfptr++) {
284 		int new_fd;
285 		err = security_file_receive(fp[i]);
286 		if (err)
287 			break;
288 		err = get_unused_fd_flags(MSG_CMSG_CLOEXEC & kmsg->msg_flags
289 					  ? O_CLOEXEC : 0);
290 		if (err < 0)
291 			break;
292 		new_fd = err;
293 		err = put_user(new_fd, cmfptr);
294 		if (err) {
295 			put_unused_fd(new_fd);
296 			break;
297 		}
298 		/* Bump the usage count and install the file. */
299 		get_file(fp[i]);
300 		fd_install(new_fd, fp[i]);
301 	}
302 
303 	if (i > 0) {
304 		int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
305 		err = put_user(SOL_SOCKET, &cm->cmsg_level);
306 		if (!err)
307 			err = put_user(SCM_RIGHTS, &cm->cmsg_type);
308 		if (!err)
309 			err = put_user(cmlen, &cm->cmsg_len);
310 		if (!err) {
311 			cmlen = CMSG_COMPAT_SPACE(i * sizeof(int));
312 			kmsg->msg_control += cmlen;
313 			kmsg->msg_controllen -= cmlen;
314 		}
315 	}
316 	if (i < fdnum)
317 		kmsg->msg_flags |= MSG_CTRUNC;
318 
319 	/*
320 	 * All of the files that fit in the message have had their
321 	 * usage counts incremented, so we just free the list.
322 	 */
323 	__scm_destroy(scm);
324 }
325 
326 /*
327  * A struct sock_filter is architecture independent.
328  */
329 struct compat_sock_fprog {
330 	u16		len;
331 	compat_uptr_t	filter;		/* struct sock_filter * */
332 };
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 compat_sock_fprog __user *fprog32 = (struct compat_sock_fprog __user *)optval;
338 	struct sock_fprog __user *kfprog = compat_alloc_user_space(sizeof(struct sock_fprog));
339 	compat_uptr_t ptr;
340 	u16 len;
341 
342 	if (!access_ok(VERIFY_READ, fprog32, sizeof(*fprog32)) ||
343 	    !access_ok(VERIFY_WRITE, kfprog, sizeof(struct sock_fprog)) ||
344 	    __get_user(len, &fprog32->len) ||
345 	    __get_user(ptr, &fprog32->filter) ||
346 	    __put_user(len, &kfprog->len) ||
347 	    __put_user(compat_ptr(ptr), &kfprog->filter))
348 		return -EFAULT;
349 
350 	return sock_setsockopt(sock, level, optname, (char __user *)kfprog,
351 			      sizeof(struct sock_fprog));
352 }
353 
354 static int do_set_sock_timeout(struct socket *sock, int level,
355 		int optname, char __user *optval, unsigned int optlen)
356 {
357 	struct compat_timeval __user *up = (struct compat_timeval __user *)optval;
358 	struct timeval ktime;
359 	mm_segment_t old_fs;
360 	int err;
361 
362 	if (optlen < sizeof(*up))
363 		return -EINVAL;
364 	if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
365 	    __get_user(ktime.tv_sec, &up->tv_sec) ||
366 	    __get_user(ktime.tv_usec, &up->tv_usec))
367 		return -EFAULT;
368 	old_fs = get_fs();
369 	set_fs(KERNEL_DS);
370 	err = sock_setsockopt(sock, level, optname, (char *)&ktime, sizeof(ktime));
371 	set_fs(old_fs);
372 
373 	return err;
374 }
375 
376 static int compat_sock_setsockopt(struct socket *sock, int level, int optname,
377 				char __user *optval, unsigned int optlen)
378 {
379 	if (optname == SO_ATTACH_FILTER)
380 		return do_set_attach_filter(sock, level, optname,
381 					    optval, optlen);
382 	if (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO)
383 		return do_set_sock_timeout(sock, level, optname, optval, optlen);
384 
385 	return sock_setsockopt(sock, level, optname, optval, optlen);
386 }
387 
388 asmlinkage long compat_sys_setsockopt(int fd, int level, int optname,
389 				char __user *optval, unsigned int optlen)
390 {
391 	int err;
392 	struct socket *sock = sockfd_lookup(fd, &err);
393 
394 	if (sock) {
395 		err = security_socket_setsockopt(sock, level, optname);
396 		if (err) {
397 			sockfd_put(sock);
398 			return err;
399 		}
400 
401 		if (level == SOL_SOCKET)
402 			err = compat_sock_setsockopt(sock, level,
403 					optname, optval, optlen);
404 		else if (sock->ops->compat_setsockopt)
405 			err = sock->ops->compat_setsockopt(sock, level,
406 					optname, optval, optlen);
407 		else
408 			err = sock->ops->setsockopt(sock, level,
409 					optname, optval, optlen);
410 		sockfd_put(sock);
411 	}
412 	return err;
413 }
414 
415 static int do_get_sock_timeout(struct socket *sock, int level, int optname,
416 		char __user *optval, int __user *optlen)
417 {
418 	struct compat_timeval __user *up;
419 	struct timeval ktime;
420 	mm_segment_t old_fs;
421 	int len, err;
422 
423 	up = (struct compat_timeval __user *) optval;
424 	if (get_user(len, optlen))
425 		return -EFAULT;
426 	if (len < sizeof(*up))
427 		return -EINVAL;
428 	len = sizeof(ktime);
429 	old_fs = get_fs();
430 	set_fs(KERNEL_DS);
431 	err = sock_getsockopt(sock, level, optname, (char *) &ktime, &len);
432 	set_fs(old_fs);
433 
434 	if (!err) {
435 		if (put_user(sizeof(*up), optlen) ||
436 		    !access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
437 		    __put_user(ktime.tv_sec, &up->tv_sec) ||
438 		    __put_user(ktime.tv_usec, &up->tv_usec))
439 			err = -EFAULT;
440 	}
441 	return err;
442 }
443 
444 static int compat_sock_getsockopt(struct socket *sock, int level, int optname,
445 				char __user *optval, int __user *optlen)
446 {
447 	if (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO)
448 		return do_get_sock_timeout(sock, level, optname, optval, optlen);
449 	return sock_getsockopt(sock, level, optname, optval, optlen);
450 }
451 
452 int compat_sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
453 {
454 	struct compat_timeval __user *ctv =
455 			(struct compat_timeval __user *) userstamp;
456 	int err = -ENOENT;
457 	struct timeval tv;
458 
459 	if (!sock_flag(sk, SOCK_TIMESTAMP))
460 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
461 	tv = ktime_to_timeval(sk->sk_stamp);
462 	if (tv.tv_sec == -1)
463 		return err;
464 	if (tv.tv_sec == 0) {
465 		sk->sk_stamp = ktime_get_real();
466 		tv = ktime_to_timeval(sk->sk_stamp);
467 	}
468 	err = 0;
469 	if (put_user(tv.tv_sec, &ctv->tv_sec) ||
470 			put_user(tv.tv_usec, &ctv->tv_usec))
471 		err = -EFAULT;
472 	return err;
473 }
474 EXPORT_SYMBOL(compat_sock_get_timestamp);
475 
476 int compat_sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
477 {
478 	struct compat_timespec __user *ctv =
479 			(struct compat_timespec __user *) userstamp;
480 	int err = -ENOENT;
481 	struct timespec ts;
482 
483 	if (!sock_flag(sk, SOCK_TIMESTAMP))
484 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
485 	ts = ktime_to_timespec(sk->sk_stamp);
486 	if (ts.tv_sec == -1)
487 		return err;
488 	if (ts.tv_sec == 0) {
489 		sk->sk_stamp = ktime_get_real();
490 		ts = ktime_to_timespec(sk->sk_stamp);
491 	}
492 	err = 0;
493 	if (put_user(ts.tv_sec, &ctv->tv_sec) ||
494 			put_user(ts.tv_nsec, &ctv->tv_nsec))
495 		err = -EFAULT;
496 	return err;
497 }
498 EXPORT_SYMBOL(compat_sock_get_timestampns);
499 
500 asmlinkage long compat_sys_getsockopt(int fd, int level, int optname,
501 				char __user *optval, int __user *optlen)
502 {
503 	int err;
504 	struct socket *sock = sockfd_lookup(fd, &err);
505 
506 	if (sock) {
507 		err = security_socket_getsockopt(sock, level, optname);
508 		if (err) {
509 			sockfd_put(sock);
510 			return err;
511 		}
512 
513 		if (level == SOL_SOCKET)
514 			err = compat_sock_getsockopt(sock, level,
515 					optname, optval, optlen);
516 		else if (sock->ops->compat_getsockopt)
517 			err = sock->ops->compat_getsockopt(sock, level,
518 					optname, optval, optlen);
519 		else
520 			err = sock->ops->getsockopt(sock, level,
521 					optname, optval, optlen);
522 		sockfd_put(sock);
523 	}
524 	return err;
525 }
526 
527 struct compat_group_req {
528 	__u32				 gr_interface;
529 	struct __kernel_sockaddr_storage gr_group
530 		__attribute__ ((aligned(4)));
531 } __packed;
532 
533 struct compat_group_source_req {
534 	__u32				 gsr_interface;
535 	struct __kernel_sockaddr_storage gsr_group
536 		__attribute__ ((aligned(4)));
537 	struct __kernel_sockaddr_storage gsr_source
538 		__attribute__ ((aligned(4)));
539 } __packed;
540 
541 struct compat_group_filter {
542 	__u32				 gf_interface;
543 	struct __kernel_sockaddr_storage gf_group
544 		__attribute__ ((aligned(4)));
545 	__u32				 gf_fmode;
546 	__u32				 gf_numsrc;
547 	struct __kernel_sockaddr_storage gf_slist[1]
548 		__attribute__ ((aligned(4)));
549 } __packed;
550 
551 #define __COMPAT_GF0_SIZE (sizeof(struct compat_group_filter) - \
552 			sizeof(struct __kernel_sockaddr_storage))
553 
554 
555 int compat_mc_setsockopt(struct sock *sock, int level, int optname,
556 	char __user *optval, unsigned int optlen,
557 	int (*setsockopt)(struct sock *, int, int, char __user *, unsigned int))
558 {
559 	char __user	*koptval = optval;
560 	int		koptlen = optlen;
561 
562 	switch (optname) {
563 	case MCAST_JOIN_GROUP:
564 	case MCAST_LEAVE_GROUP:
565 	{
566 		struct compat_group_req __user *gr32 = (void *)optval;
567 		struct group_req __user *kgr =
568 			compat_alloc_user_space(sizeof(struct group_req));
569 		u32 interface;
570 
571 		if (!access_ok(VERIFY_READ, gr32, sizeof(*gr32)) ||
572 		    !access_ok(VERIFY_WRITE, kgr, sizeof(struct group_req)) ||
573 		    __get_user(interface, &gr32->gr_interface) ||
574 		    __put_user(interface, &kgr->gr_interface) ||
575 		    copy_in_user(&kgr->gr_group, &gr32->gr_group,
576 				sizeof(kgr->gr_group)))
577 			return -EFAULT;
578 		koptval = (char __user *)kgr;
579 		koptlen = sizeof(struct group_req);
580 		break;
581 	}
582 	case MCAST_JOIN_SOURCE_GROUP:
583 	case MCAST_LEAVE_SOURCE_GROUP:
584 	case MCAST_BLOCK_SOURCE:
585 	case MCAST_UNBLOCK_SOURCE:
586 	{
587 		struct compat_group_source_req __user *gsr32 = (void *)optval;
588 		struct group_source_req __user *kgsr = compat_alloc_user_space(
589 			sizeof(struct group_source_req));
590 		u32 interface;
591 
592 		if (!access_ok(VERIFY_READ, gsr32, sizeof(*gsr32)) ||
593 		    !access_ok(VERIFY_WRITE, kgsr,
594 			sizeof(struct group_source_req)) ||
595 		    __get_user(interface, &gsr32->gsr_interface) ||
596 		    __put_user(interface, &kgsr->gsr_interface) ||
597 		    copy_in_user(&kgsr->gsr_group, &gsr32->gsr_group,
598 				sizeof(kgsr->gsr_group)) ||
599 		    copy_in_user(&kgsr->gsr_source, &gsr32->gsr_source,
600 				sizeof(kgsr->gsr_source)))
601 			return -EFAULT;
602 		koptval = (char __user *)kgsr;
603 		koptlen = sizeof(struct group_source_req);
604 		break;
605 	}
606 	case MCAST_MSFILTER:
607 	{
608 		struct compat_group_filter __user *gf32 = (void *)optval;
609 		struct group_filter __user *kgf;
610 		u32 interface, fmode, numsrc;
611 
612 		if (!access_ok(VERIFY_READ, gf32, __COMPAT_GF0_SIZE) ||
613 		    __get_user(interface, &gf32->gf_interface) ||
614 		    __get_user(fmode, &gf32->gf_fmode) ||
615 		    __get_user(numsrc, &gf32->gf_numsrc))
616 			return -EFAULT;
617 		koptlen = optlen + sizeof(struct group_filter) -
618 				sizeof(struct compat_group_filter);
619 		if (koptlen < GROUP_FILTER_SIZE(numsrc))
620 			return -EINVAL;
621 		kgf = compat_alloc_user_space(koptlen);
622 		if (!access_ok(VERIFY_WRITE, kgf, koptlen) ||
623 		    __put_user(interface, &kgf->gf_interface) ||
624 		    __put_user(fmode, &kgf->gf_fmode) ||
625 		    __put_user(numsrc, &kgf->gf_numsrc) ||
626 		    copy_in_user(&kgf->gf_group, &gf32->gf_group,
627 				sizeof(kgf->gf_group)) ||
628 		    (numsrc && copy_in_user(kgf->gf_slist, gf32->gf_slist,
629 				numsrc * sizeof(kgf->gf_slist[0]))))
630 			return -EFAULT;
631 		koptval = (char __user *)kgf;
632 		break;
633 	}
634 
635 	default:
636 		break;
637 	}
638 	return setsockopt(sock, level, optname, koptval, koptlen);
639 }
640 EXPORT_SYMBOL(compat_mc_setsockopt);
641 
642 int compat_mc_getsockopt(struct sock *sock, int level, int optname,
643 	char __user *optval, int __user *optlen,
644 	int (*getsockopt)(struct sock *, int, int, char __user *, int __user *))
645 {
646 	struct compat_group_filter __user *gf32 = (void *)optval;
647 	struct group_filter __user *kgf;
648 	int __user	*koptlen;
649 	u32 interface, fmode, numsrc;
650 	int klen, ulen, err;
651 
652 	if (optname != MCAST_MSFILTER)
653 		return getsockopt(sock, level, optname, optval, optlen);
654 
655 	koptlen = compat_alloc_user_space(sizeof(*koptlen));
656 	if (!access_ok(VERIFY_READ, optlen, sizeof(*optlen)) ||
657 	    __get_user(ulen, optlen))
658 		return -EFAULT;
659 
660 	/* adjust len for pad */
661 	klen = ulen + sizeof(*kgf) - sizeof(*gf32);
662 
663 	if (klen < GROUP_FILTER_SIZE(0))
664 		return -EINVAL;
665 
666 	if (!access_ok(VERIFY_WRITE, koptlen, sizeof(*koptlen)) ||
667 	    __put_user(klen, koptlen))
668 		return -EFAULT;
669 
670 	/* have to allow space for previous compat_alloc_user_space, too */
671 	kgf = compat_alloc_user_space(klen+sizeof(*optlen));
672 
673 	if (!access_ok(VERIFY_READ, gf32, __COMPAT_GF0_SIZE) ||
674 	    __get_user(interface, &gf32->gf_interface) ||
675 	    __get_user(fmode, &gf32->gf_fmode) ||
676 	    __get_user(numsrc, &gf32->gf_numsrc) ||
677 	    __put_user(interface, &kgf->gf_interface) ||
678 	    __put_user(fmode, &kgf->gf_fmode) ||
679 	    __put_user(numsrc, &kgf->gf_numsrc) ||
680 	    copy_in_user(&kgf->gf_group, &gf32->gf_group, sizeof(kgf->gf_group)))
681 		return -EFAULT;
682 
683 	err = getsockopt(sock, level, optname, (char __user *)kgf, koptlen);
684 	if (err)
685 		return err;
686 
687 	if (!access_ok(VERIFY_READ, koptlen, sizeof(*koptlen)) ||
688 	    __get_user(klen, koptlen))
689 		return -EFAULT;
690 
691 	ulen = klen - (sizeof(*kgf)-sizeof(*gf32));
692 
693 	if (!access_ok(VERIFY_WRITE, optlen, sizeof(*optlen)) ||
694 	    __put_user(ulen, optlen))
695 		return -EFAULT;
696 
697 	if (!access_ok(VERIFY_READ, kgf, klen) ||
698 	    !access_ok(VERIFY_WRITE, gf32, ulen) ||
699 	    __get_user(interface, &kgf->gf_interface) ||
700 	    __get_user(fmode, &kgf->gf_fmode) ||
701 	    __get_user(numsrc, &kgf->gf_numsrc) ||
702 	    __put_user(interface, &gf32->gf_interface) ||
703 	    __put_user(fmode, &gf32->gf_fmode) ||
704 	    __put_user(numsrc, &gf32->gf_numsrc))
705 		return -EFAULT;
706 	if (numsrc) {
707 		int copylen;
708 
709 		klen -= GROUP_FILTER_SIZE(0);
710 		copylen = numsrc * sizeof(gf32->gf_slist[0]);
711 		if (copylen > klen)
712 			copylen = klen;
713 		if (copy_in_user(gf32->gf_slist, kgf->gf_slist, copylen))
714 			return -EFAULT;
715 	}
716 	return err;
717 }
718 EXPORT_SYMBOL(compat_mc_getsockopt);
719 
720 
721 /* Argument list sizes for compat_sys_socketcall */
722 #define AL(x) ((x) * sizeof(u32))
723 static unsigned char nas[20] = {
724 	AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
725 	AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
726 	AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
727 	AL(4), AL(5)
728 };
729 #undef AL
730 
731 asmlinkage long compat_sys_sendmsg(int fd, struct compat_msghdr __user *msg, unsigned flags)
732 {
733 	return sys_sendmsg(fd, (struct msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
734 }
735 
736 asmlinkage long compat_sys_recvmsg(int fd, struct compat_msghdr __user *msg, unsigned int flags)
737 {
738 	return sys_recvmsg(fd, (struct msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
739 }
740 
741 asmlinkage long compat_sys_recv(int fd, void __user *buf, size_t len, unsigned flags)
742 {
743 	return sys_recv(fd, buf, len, flags | MSG_CMSG_COMPAT);
744 }
745 
746 asmlinkage long compat_sys_recvfrom(int fd, void __user *buf, size_t len,
747 				    unsigned flags, struct sockaddr __user *addr,
748 				    int __user *addrlen)
749 {
750 	return sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr, addrlen);
751 }
752 
753 asmlinkage long compat_sys_recvmmsg(int fd, struct compat_mmsghdr __user *mmsg,
754 				    unsigned vlen, unsigned int flags,
755 				    struct compat_timespec __user *timeout)
756 {
757 	int datagrams;
758 	struct timespec ktspec;
759 
760 	if (timeout == NULL)
761 		return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
762 				      flags | MSG_CMSG_COMPAT, NULL);
763 
764 	if (get_compat_timespec(&ktspec, timeout))
765 		return -EFAULT;
766 
767 	datagrams = __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
768 				   flags | MSG_CMSG_COMPAT, &ktspec);
769 	if (datagrams > 0 && put_compat_timespec(&ktspec, timeout))
770 		datagrams = -EFAULT;
771 
772 	return datagrams;
773 }
774 
775 asmlinkage long compat_sys_socketcall(int call, u32 __user *args)
776 {
777 	int ret;
778 	u32 a[6];
779 	u32 a0, a1;
780 
781 	if (call < SYS_SOCKET || call > SYS_RECVMMSG)
782 		return -EINVAL;
783 	if (copy_from_user(a, args, nas[call]))
784 		return -EFAULT;
785 	a0 = a[0];
786 	a1 = a[1];
787 
788 	switch (call) {
789 	case SYS_SOCKET:
790 		ret = sys_socket(a0, a1, a[2]);
791 		break;
792 	case SYS_BIND:
793 		ret = sys_bind(a0, compat_ptr(a1), a[2]);
794 		break;
795 	case SYS_CONNECT:
796 		ret = sys_connect(a0, compat_ptr(a1), a[2]);
797 		break;
798 	case SYS_LISTEN:
799 		ret = sys_listen(a0, a1);
800 		break;
801 	case SYS_ACCEPT:
802 		ret = sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0);
803 		break;
804 	case SYS_GETSOCKNAME:
805 		ret = sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]));
806 		break;
807 	case SYS_GETPEERNAME:
808 		ret = sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2]));
809 		break;
810 	case SYS_SOCKETPAIR:
811 		ret = sys_socketpair(a0, a1, a[2], compat_ptr(a[3]));
812 		break;
813 	case SYS_SEND:
814 		ret = sys_send(a0, compat_ptr(a1), a[2], a[3]);
815 		break;
816 	case SYS_SENDTO:
817 		ret = sys_sendto(a0, compat_ptr(a1), a[2], a[3], compat_ptr(a[4]), a[5]);
818 		break;
819 	case SYS_RECV:
820 		ret = compat_sys_recv(a0, compat_ptr(a1), a[2], a[3]);
821 		break;
822 	case SYS_RECVFROM:
823 		ret = compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
824 					  compat_ptr(a[4]), compat_ptr(a[5]));
825 		break;
826 	case SYS_SHUTDOWN:
827 		ret = sys_shutdown(a0, a1);
828 		break;
829 	case SYS_SETSOCKOPT:
830 		ret = compat_sys_setsockopt(a0, a1, a[2],
831 				compat_ptr(a[3]), a[4]);
832 		break;
833 	case SYS_GETSOCKOPT:
834 		ret = compat_sys_getsockopt(a0, a1, a[2],
835 				compat_ptr(a[3]), compat_ptr(a[4]));
836 		break;
837 	case SYS_SENDMSG:
838 		ret = compat_sys_sendmsg(a0, compat_ptr(a1), a[2]);
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