xref: /linux/net/compat.c (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
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 			return -EFAULT;
46 
47 		if (len > INT_MAX - tot_len)
48 			len = INT_MAX - tot_len;
49 
50 		tot_len += len;
51 		kiov->iov_base = compat_ptr(buf);
52 		kiov->iov_len = (__kernel_size_t) len;
53 		uiov32++;
54 		kiov++;
55 		niov--;
56 	}
57 	return tot_len;
58 }
59 
60 int get_compat_msghdr(struct msghdr *kmsg, struct compat_msghdr __user *umsg)
61 {
62 	compat_uptr_t tmp1, tmp2, tmp3;
63 
64 	if (!access_ok(VERIFY_READ, umsg, sizeof(*umsg)) ||
65 	    __get_user(tmp1, &umsg->msg_name) ||
66 	    __get_user(kmsg->msg_namelen, &umsg->msg_namelen) ||
67 	    __get_user(tmp2, &umsg->msg_iov) ||
68 	    __get_user(kmsg->msg_iovlen, &umsg->msg_iovlen) ||
69 	    __get_user(tmp3, &umsg->msg_control) ||
70 	    __get_user(kmsg->msg_controllen, &umsg->msg_controllen) ||
71 	    __get_user(kmsg->msg_flags, &umsg->msg_flags))
72 		return -EFAULT;
73 	kmsg->msg_name = compat_ptr(tmp1);
74 	kmsg->msg_iov = compat_ptr(tmp2);
75 	kmsg->msg_control = compat_ptr(tmp3);
76 	return 0;
77 }
78 
79 /* I've named the args so it is easy to tell whose space the pointers are in. */
80 int verify_compat_iovec(struct msghdr *kern_msg, struct iovec *kern_iov,
81 		   struct sockaddr *kern_address, int mode)
82 {
83 	int tot_len;
84 
85 	if (kern_msg->msg_namelen) {
86 		if (mode == VERIFY_READ) {
87 			int err = move_addr_to_kernel(kern_msg->msg_name,
88 						      kern_msg->msg_namelen,
89 						      kern_address);
90 			if (err < 0)
91 				return err;
92 		}
93 		kern_msg->msg_name = kern_address;
94 	} else
95 		kern_msg->msg_name = NULL;
96 
97 	tot_len = iov_from_user_compat_to_kern(kern_iov,
98 					  (struct compat_iovec __user *)kern_msg->msg_iov,
99 					  kern_msg->msg_iovlen);
100 	if (tot_len >= 0)
101 		kern_msg->msg_iov = kern_iov;
102 
103 	return tot_len;
104 }
105 
106 /* Bleech... */
107 #define CMSG_COMPAT_ALIGN(len)	ALIGN((len), sizeof(s32))
108 
109 #define CMSG_COMPAT_DATA(cmsg)				\
110 	((void __user *)((char __user *)(cmsg) + CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr))))
111 #define CMSG_COMPAT_SPACE(len)				\
112 	(CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)) + CMSG_COMPAT_ALIGN(len))
113 #define CMSG_COMPAT_LEN(len)				\
114 	(CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)) + (len))
115 
116 #define CMSG_COMPAT_FIRSTHDR(msg)			\
117 	(((msg)->msg_controllen) >= sizeof(struct compat_cmsghdr) ?	\
118 	 (struct compat_cmsghdr __user *)((msg)->msg_control) :		\
119 	 (struct compat_cmsghdr __user *)NULL)
120 
121 #define CMSG_COMPAT_OK(ucmlen, ucmsg, mhdr) \
122 	((ucmlen) >= sizeof(struct compat_cmsghdr) && \
123 	 (ucmlen) <= (unsigned long) \
124 	 ((mhdr)->msg_controllen - \
125 	  ((char *)(ucmsg) - (char *)(mhdr)->msg_control)))
126 
127 static inline struct compat_cmsghdr __user *cmsg_compat_nxthdr(struct msghdr *msg,
128 		struct compat_cmsghdr __user *cmsg, int cmsg_len)
129 {
130 	char __user *ptr = (char __user *)cmsg + CMSG_COMPAT_ALIGN(cmsg_len);
131 	if ((unsigned long)(ptr + 1 - (char __user *)msg->msg_control) >
132 			msg->msg_controllen)
133 		return NULL;
134 	return (struct compat_cmsghdr __user *)ptr;
135 }
136 
137 /* There is a lot of hair here because the alignment rules (and
138  * thus placement) of cmsg headers and length are different for
139  * 32-bit apps.  -DaveM
140  */
141 int cmsghdr_from_user_compat_to_kern(struct msghdr *kmsg, struct sock *sk,
142 			       unsigned char *stackbuf, int stackbuf_size)
143 {
144 	struct compat_cmsghdr __user *ucmsg;
145 	struct cmsghdr *kcmsg, *kcmsg_base;
146 	compat_size_t ucmlen;
147 	__kernel_size_t kcmlen, tmp;
148 	int err = -EFAULT;
149 
150 	kcmlen = 0;
151 	kcmsg_base = kcmsg = (struct cmsghdr *)stackbuf;
152 	ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
153 	while (ucmsg != NULL) {
154 		if (get_user(ucmlen, &ucmsg->cmsg_len))
155 			return -EFAULT;
156 
157 		/* Catch bogons. */
158 		if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
159 			return -EINVAL;
160 
161 		tmp = ((ucmlen - CMSG_COMPAT_ALIGN(sizeof(*ucmsg))) +
162 		       CMSG_ALIGN(sizeof(struct cmsghdr)));
163 		tmp = CMSG_ALIGN(tmp);
164 		kcmlen += tmp;
165 		ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
166 	}
167 	if (kcmlen == 0)
168 		return -EINVAL;
169 
170 	/* The kcmlen holds the 64-bit version of the control length.
171 	 * It may not be modified as we do not stick it into the kmsg
172 	 * until we have successfully copied over all of the data
173 	 * from the user.
174 	 */
175 	if (kcmlen > stackbuf_size)
176 		kcmsg_base = kcmsg = sock_kmalloc(sk, kcmlen, GFP_KERNEL);
177 	if (kcmsg == NULL)
178 		return -ENOBUFS;
179 
180 	/* Now copy them over neatly. */
181 	memset(kcmsg, 0, kcmlen);
182 	ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
183 	while (ucmsg != NULL) {
184 		if (__get_user(ucmlen, &ucmsg->cmsg_len))
185 			goto Efault;
186 		if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
187 			goto Einval;
188 		tmp = ((ucmlen - CMSG_COMPAT_ALIGN(sizeof(*ucmsg))) +
189 		       CMSG_ALIGN(sizeof(struct cmsghdr)));
190 		if ((char *)kcmsg_base + kcmlen - (char *)kcmsg < CMSG_ALIGN(tmp))
191 			goto Einval;
192 		kcmsg->cmsg_len = tmp;
193 		tmp = CMSG_ALIGN(tmp);
194 		if (__get_user(kcmsg->cmsg_level, &ucmsg->cmsg_level) ||
195 		    __get_user(kcmsg->cmsg_type, &ucmsg->cmsg_type) ||
196 		    copy_from_user(CMSG_DATA(kcmsg),
197 				   CMSG_COMPAT_DATA(ucmsg),
198 				   (ucmlen - CMSG_COMPAT_ALIGN(sizeof(*ucmsg)))))
199 			goto Efault;
200 
201 		/* Advance. */
202 		kcmsg = (struct cmsghdr *)((char *)kcmsg + tmp);
203 		ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
204 	}
205 
206 	/* Ok, looks like we made it.  Hook it up and return success. */
207 	kmsg->msg_control = kcmsg_base;
208 	kmsg->msg_controllen = kcmlen;
209 	return 0;
210 
211 Einval:
212 	err = -EINVAL;
213 Efault:
214 	if (kcmsg_base != (struct cmsghdr *)stackbuf)
215 		sock_kfree_s(sk, kcmsg_base, kcmlen);
216 	return err;
217 }
218 
219 int put_cmsg_compat(struct msghdr *kmsg, int level, int type, int len, void *data)
220 {
221 	struct compat_timeval ctv;
222 	struct compat_timespec cts[3];
223 	struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
224 	struct compat_cmsghdr cmhdr;
225 	int cmlen;
226 
227 	if (cm == NULL || kmsg->msg_controllen < sizeof(*cm)) {
228 		kmsg->msg_flags |= MSG_CTRUNC;
229 		return 0; /* XXX: return error? check spec. */
230 	}
231 
232 	if (level == SOL_SOCKET && type == SCM_TIMESTAMP) {
233 		struct timeval *tv = (struct timeval *)data;
234 		ctv.tv_sec = tv->tv_sec;
235 		ctv.tv_usec = tv->tv_usec;
236 		data = &ctv;
237 		len = sizeof(ctv);
238 	}
239 	if (level == SOL_SOCKET &&
240 	    (type == SCM_TIMESTAMPNS || type == SCM_TIMESTAMPING)) {
241 		int count = type == SCM_TIMESTAMPNS ? 1 : 3;
242 		int i;
243 		struct timespec *ts = (struct timespec *)data;
244 		for (i = 0; i < count; i++) {
245 			cts[i].tv_sec = ts[i].tv_sec;
246 			cts[i].tv_nsec = ts[i].tv_nsec;
247 		}
248 		data = &cts;
249 		len = sizeof(cts[0]) * count;
250 	}
251 
252 	cmlen = CMSG_COMPAT_LEN(len);
253 	if (kmsg->msg_controllen < cmlen) {
254 		kmsg->msg_flags |= MSG_CTRUNC;
255 		cmlen = kmsg->msg_controllen;
256 	}
257 	cmhdr.cmsg_level = level;
258 	cmhdr.cmsg_type = type;
259 	cmhdr.cmsg_len = cmlen;
260 
261 	if (copy_to_user(cm, &cmhdr, sizeof cmhdr))
262 		return -EFAULT;
263 	if (copy_to_user(CMSG_COMPAT_DATA(cm), data, cmlen - sizeof(struct compat_cmsghdr)))
264 		return -EFAULT;
265 	cmlen = CMSG_COMPAT_SPACE(len);
266 	if (kmsg->msg_controllen < cmlen)
267 		cmlen = kmsg->msg_controllen;
268 	kmsg->msg_control += cmlen;
269 	kmsg->msg_controllen -= cmlen;
270 	return 0;
271 }
272 
273 void scm_detach_fds_compat(struct msghdr *kmsg, struct scm_cookie *scm)
274 {
275 	struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
276 	int fdmax = (kmsg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int);
277 	int fdnum = scm->fp->count;
278 	struct file **fp = scm->fp->fp;
279 	int __user *cmfptr;
280 	int err = 0, i;
281 
282 	if (fdnum < fdmax)
283 		fdmax = fdnum;
284 
285 	for (i = 0, cmfptr = (int __user *) CMSG_COMPAT_DATA(cm); i < fdmax; i++, cmfptr++) {
286 		int new_fd;
287 		err = security_file_receive(fp[i]);
288 		if (err)
289 			break;
290 		err = get_unused_fd_flags(MSG_CMSG_CLOEXEC & kmsg->msg_flags
291 					  ? O_CLOEXEC : 0);
292 		if (err < 0)
293 			break;
294 		new_fd = err;
295 		err = put_user(new_fd, cmfptr);
296 		if (err) {
297 			put_unused_fd(new_fd);
298 			break;
299 		}
300 		/* Bump the usage count and install the file. */
301 		get_file(fp[i]);
302 		fd_install(new_fd, fp[i]);
303 	}
304 
305 	if (i > 0) {
306 		int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
307 		err = put_user(SOL_SOCKET, &cm->cmsg_level);
308 		if (!err)
309 			err = put_user(SCM_RIGHTS, &cm->cmsg_type);
310 		if (!err)
311 			err = put_user(cmlen, &cm->cmsg_len);
312 		if (!err) {
313 			cmlen = CMSG_COMPAT_SPACE(i * sizeof(int));
314 			kmsg->msg_control += cmlen;
315 			kmsg->msg_controllen -= cmlen;
316 		}
317 	}
318 	if (i < fdnum)
319 		kmsg->msg_flags |= MSG_CTRUNC;
320 
321 	/*
322 	 * All of the files that fit in the message have had their
323 	 * usage counts incremented, so we just free the list.
324 	 */
325 	__scm_destroy(scm);
326 }
327 
328 /*
329  * A struct sock_filter is architecture independent.
330  */
331 struct compat_sock_fprog {
332 	u16		len;
333 	compat_uptr_t	filter;		/* struct sock_filter * */
334 };
335 
336 static int do_set_attach_filter(struct socket *sock, int level, int optname,
337 				char __user *optval, unsigned int optlen)
338 {
339 	struct compat_sock_fprog __user *fprog32 = (struct compat_sock_fprog __user *)optval;
340 	struct sock_fprog __user *kfprog = compat_alloc_user_space(sizeof(struct sock_fprog));
341 	compat_uptr_t ptr;
342 	u16 len;
343 
344 	if (!access_ok(VERIFY_READ, fprog32, sizeof(*fprog32)) ||
345 	    !access_ok(VERIFY_WRITE, kfprog, sizeof(struct sock_fprog)) ||
346 	    __get_user(len, &fprog32->len) ||
347 	    __get_user(ptr, &fprog32->filter) ||
348 	    __put_user(len, &kfprog->len) ||
349 	    __put_user(compat_ptr(ptr), &kfprog->filter))
350 		return -EFAULT;
351 
352 	return sock_setsockopt(sock, level, optname, (char __user *)kfprog,
353 			      sizeof(struct sock_fprog));
354 }
355 
356 static int do_set_sock_timeout(struct socket *sock, int level,
357 		int optname, char __user *optval, unsigned int optlen)
358 {
359 	struct compat_timeval __user *up = (struct compat_timeval __user *)optval;
360 	struct timeval ktime;
361 	mm_segment_t old_fs;
362 	int err;
363 
364 	if (optlen < sizeof(*up))
365 		return -EINVAL;
366 	if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
367 	    __get_user(ktime.tv_sec, &up->tv_sec) ||
368 	    __get_user(ktime.tv_usec, &up->tv_usec))
369 		return -EFAULT;
370 	old_fs = get_fs();
371 	set_fs(KERNEL_DS);
372 	err = sock_setsockopt(sock, level, optname, (char *)&ktime, sizeof(ktime));
373 	set_fs(old_fs);
374 
375 	return err;
376 }
377 
378 static int compat_sock_setsockopt(struct socket *sock, int level, int optname,
379 				char __user *optval, unsigned int optlen)
380 {
381 	if (optname == SO_ATTACH_FILTER)
382 		return do_set_attach_filter(sock, level, optname,
383 					    optval, optlen);
384 	if (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO)
385 		return do_set_sock_timeout(sock, level, optname, optval, optlen);
386 
387 	return sock_setsockopt(sock, level, optname, optval, optlen);
388 }
389 
390 asmlinkage long compat_sys_setsockopt(int fd, int level, int optname,
391 				char __user *optval, unsigned int optlen)
392 {
393 	int err;
394 	struct socket *sock = sockfd_lookup(fd, &err);
395 
396 	if (sock) {
397 		err = security_socket_setsockopt(sock, level, optname);
398 		if (err) {
399 			sockfd_put(sock);
400 			return err;
401 		}
402 
403 		if (level == SOL_SOCKET)
404 			err = compat_sock_setsockopt(sock, level,
405 					optname, optval, optlen);
406 		else if (sock->ops->compat_setsockopt)
407 			err = sock->ops->compat_setsockopt(sock, level,
408 					optname, optval, optlen);
409 		else
410 			err = sock->ops->setsockopt(sock, level,
411 					optname, optval, optlen);
412 		sockfd_put(sock);
413 	}
414 	return err;
415 }
416 
417 static int do_get_sock_timeout(struct socket *sock, int level, int optname,
418 		char __user *optval, int __user *optlen)
419 {
420 	struct compat_timeval __user *up;
421 	struct timeval ktime;
422 	mm_segment_t old_fs;
423 	int len, err;
424 
425 	up = (struct compat_timeval __user *) optval;
426 	if (get_user(len, optlen))
427 		return -EFAULT;
428 	if (len < sizeof(*up))
429 		return -EINVAL;
430 	len = sizeof(ktime);
431 	old_fs = get_fs();
432 	set_fs(KERNEL_DS);
433 	err = sock_getsockopt(sock, level, optname, (char *) &ktime, &len);
434 	set_fs(old_fs);
435 
436 	if (!err) {
437 		if (put_user(sizeof(*up), optlen) ||
438 		    !access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
439 		    __put_user(ktime.tv_sec, &up->tv_sec) ||
440 		    __put_user(ktime.tv_usec, &up->tv_usec))
441 			err = -EFAULT;
442 	}
443 	return err;
444 }
445 
446 static int compat_sock_getsockopt(struct socket *sock, int level, int optname,
447 				char __user *optval, int __user *optlen)
448 {
449 	if (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO)
450 		return do_get_sock_timeout(sock, level, optname, optval, optlen);
451 	return sock_getsockopt(sock, level, optname, optval, optlen);
452 }
453 
454 int compat_sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
455 {
456 	struct compat_timeval __user *ctv =
457 			(struct compat_timeval __user *) userstamp;
458 	int err = -ENOENT;
459 	struct timeval tv;
460 
461 	if (!sock_flag(sk, SOCK_TIMESTAMP))
462 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
463 	tv = ktime_to_timeval(sk->sk_stamp);
464 	if (tv.tv_sec == -1)
465 		return err;
466 	if (tv.tv_sec == 0) {
467 		sk->sk_stamp = ktime_get_real();
468 		tv = ktime_to_timeval(sk->sk_stamp);
469 	}
470 	err = 0;
471 	if (put_user(tv.tv_sec, &ctv->tv_sec) ||
472 			put_user(tv.tv_usec, &ctv->tv_usec))
473 		err = -EFAULT;
474 	return err;
475 }
476 EXPORT_SYMBOL(compat_sock_get_timestamp);
477 
478 int compat_sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
479 {
480 	struct compat_timespec __user *ctv =
481 			(struct compat_timespec __user *) userstamp;
482 	int err = -ENOENT;
483 	struct timespec ts;
484 
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 asmlinkage long compat_sys_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 		__attribute__ ((aligned(4)));
533 } __packed;
534 
535 struct compat_group_source_req {
536 	__u32				 gsr_interface;
537 	struct __kernel_sockaddr_storage gsr_group
538 		__attribute__ ((aligned(4)));
539 	struct __kernel_sockaddr_storage gsr_source
540 		__attribute__ ((aligned(4)));
541 } __packed;
542 
543 struct compat_group_filter {
544 	__u32				 gf_interface;
545 	struct __kernel_sockaddr_storage gf_group
546 		__attribute__ ((aligned(4)));
547 	__u32				 gf_fmode;
548 	__u32				 gf_numsrc;
549 	struct __kernel_sockaddr_storage gf_slist[1]
550 		__attribute__ ((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 asmlinkage long compat_sys_sendmsg(int fd, struct compat_msghdr __user *msg, unsigned flags)
734 {
735 	return sys_sendmsg(fd, (struct msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
736 }
737 
738 asmlinkage long compat_sys_sendmmsg(int fd, struct compat_mmsghdr __user *mmsg,
739 				    unsigned vlen, unsigned int flags)
740 {
741 	return __sys_sendmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
742 			      flags | MSG_CMSG_COMPAT);
743 }
744 
745 asmlinkage long compat_sys_recvmsg(int fd, struct compat_msghdr __user *msg, unsigned int flags)
746 {
747 	return sys_recvmsg(fd, (struct msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
748 }
749 
750 asmlinkage long compat_sys_recv(int fd, void __user *buf, size_t len, unsigned flags)
751 {
752 	return sys_recv(fd, buf, len, flags | MSG_CMSG_COMPAT);
753 }
754 
755 asmlinkage long compat_sys_recvfrom(int fd, void __user *buf, size_t len,
756 				    unsigned 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 asmlinkage long compat_sys_recvmmsg(int fd, struct compat_mmsghdr __user *mmsg,
763 				    unsigned 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 (get_compat_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 && put_compat_timespec(&ktspec, timeout))
779 		datagrams = -EFAULT;
780 
781 	return datagrams;
782 }
783 
784 asmlinkage long compat_sys_socketcall(int call, u32 __user *args)
785 {
786 	int ret;
787 	u32 a[6];
788 	u32 a0, a1;
789 
790 	if (call < SYS_SOCKET || call > SYS_SENDMMSG)
791 		return -EINVAL;
792 	if (copy_from_user(a, args, nas[call]))
793 		return -EFAULT;
794 	a0 = a[0];
795 	a1 = a[1];
796 
797 	switch (call) {
798 	case SYS_SOCKET:
799 		ret = sys_socket(a0, a1, a[2]);
800 		break;
801 	case SYS_BIND:
802 		ret = sys_bind(a0, compat_ptr(a1), a[2]);
803 		break;
804 	case SYS_CONNECT:
805 		ret = sys_connect(a0, compat_ptr(a1), a[2]);
806 		break;
807 	case SYS_LISTEN:
808 		ret = sys_listen(a0, a1);
809 		break;
810 	case SYS_ACCEPT:
811 		ret = sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0);
812 		break;
813 	case SYS_GETSOCKNAME:
814 		ret = sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]));
815 		break;
816 	case SYS_GETPEERNAME:
817 		ret = sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2]));
818 		break;
819 	case SYS_SOCKETPAIR:
820 		ret = sys_socketpair(a0, a1, a[2], compat_ptr(a[3]));
821 		break;
822 	case SYS_SEND:
823 		ret = sys_send(a0, compat_ptr(a1), a[2], a[3]);
824 		break;
825 	case SYS_SENDTO:
826 		ret = sys_sendto(a0, compat_ptr(a1), a[2], a[3], compat_ptr(a[4]), a[5]);
827 		break;
828 	case SYS_RECV:
829 		ret = compat_sys_recv(a0, compat_ptr(a1), a[2], a[3]);
830 		break;
831 	case SYS_RECVFROM:
832 		ret = compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
833 					  compat_ptr(a[4]), compat_ptr(a[5]));
834 		break;
835 	case SYS_SHUTDOWN:
836 		ret = sys_shutdown(a0, a1);
837 		break;
838 	case SYS_SETSOCKOPT:
839 		ret = compat_sys_setsockopt(a0, a1, a[2],
840 				compat_ptr(a[3]), a[4]);
841 		break;
842 	case SYS_GETSOCKOPT:
843 		ret = compat_sys_getsockopt(a0, a1, a[2],
844 				compat_ptr(a[3]), compat_ptr(a[4]));
845 		break;
846 	case SYS_SENDMSG:
847 		ret = compat_sys_sendmsg(a0, compat_ptr(a1), a[2]);
848 		break;
849 	case SYS_SENDMMSG:
850 		ret = compat_sys_sendmmsg(a0, compat_ptr(a1), a[2], a[3]);
851 		break;
852 	case SYS_RECVMSG:
853 		ret = compat_sys_recvmsg(a0, compat_ptr(a1), a[2]);
854 		break;
855 	case SYS_RECVMMSG:
856 		ret = compat_sys_recvmmsg(a0, compat_ptr(a1), a[2], a[3],
857 					  compat_ptr(a[4]));
858 		break;
859 	case SYS_ACCEPT4:
860 		ret = sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]);
861 		break;
862 	default:
863 		ret = -EINVAL;
864 		break;
865 	}
866 	return ret;
867 }
868