xref: /linux/net/compat.c (revision b4748e7ab731e436cf5db4786358ada5dd2db6dd)
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 	struct compat_msghdr msg;
41 	ssize_t err;
42 
43 	if (copy_from_user(&msg, umsg, sizeof(*umsg)))
44 		return -EFAULT;
45 
46 	kmsg->msg_flags = msg.msg_flags;
47 	kmsg->msg_namelen = msg.msg_namelen;
48 
49 	if (!msg.msg_name)
50 		kmsg->msg_namelen = 0;
51 
52 	if (kmsg->msg_namelen < 0)
53 		return -EINVAL;
54 
55 	if (kmsg->msg_namelen > sizeof(struct sockaddr_storage))
56 		kmsg->msg_namelen = sizeof(struct sockaddr_storage);
57 
58 	kmsg->msg_control = compat_ptr(msg.msg_control);
59 	kmsg->msg_controllen = msg.msg_controllen;
60 
61 	if (save_addr)
62 		*save_addr = compat_ptr(msg.msg_name);
63 
64 	if (msg.msg_name && kmsg->msg_namelen) {
65 		if (!save_addr) {
66 			err = move_addr_to_kernel(compat_ptr(msg.msg_name),
67 						  kmsg->msg_namelen,
68 						  kmsg->msg_name);
69 			if (err < 0)
70 				return err;
71 		}
72 	} else {
73 		kmsg->msg_name = NULL;
74 		kmsg->msg_namelen = 0;
75 	}
76 
77 	if (msg.msg_iovlen > UIO_MAXIOV)
78 		return -EMSGSIZE;
79 
80 	kmsg->msg_iocb = NULL;
81 
82 	return compat_import_iovec(save_addr ? READ : WRITE,
83 				   compat_ptr(msg.msg_iov), msg.msg_iovlen,
84 				   UIO_FASTIOV, iov, &kmsg->msg_iter);
85 }
86 
87 /* Bleech... */
88 #define CMSG_COMPAT_ALIGN(len)	ALIGN((len), sizeof(s32))
89 
90 #define CMSG_COMPAT_DATA(cmsg)				\
91 	((void __user *)((char __user *)(cmsg) + sizeof(struct compat_cmsghdr)))
92 #define CMSG_COMPAT_SPACE(len)				\
93 	(sizeof(struct compat_cmsghdr) + CMSG_COMPAT_ALIGN(len))
94 #define CMSG_COMPAT_LEN(len)				\
95 	(sizeof(struct compat_cmsghdr) + (len))
96 
97 #define CMSG_COMPAT_FIRSTHDR(msg)			\
98 	(((msg)->msg_controllen) >= sizeof(struct compat_cmsghdr) ?	\
99 	 (struct compat_cmsghdr __user *)((msg)->msg_control) :		\
100 	 (struct compat_cmsghdr __user *)NULL)
101 
102 #define CMSG_COMPAT_OK(ucmlen, ucmsg, mhdr) \
103 	((ucmlen) >= sizeof(struct compat_cmsghdr) && \
104 	 (ucmlen) <= (unsigned long) \
105 	 ((mhdr)->msg_controllen - \
106 	  ((char *)(ucmsg) - (char *)(mhdr)->msg_control)))
107 
108 static inline struct compat_cmsghdr __user *cmsg_compat_nxthdr(struct msghdr *msg,
109 		struct compat_cmsghdr __user *cmsg, int cmsg_len)
110 {
111 	char __user *ptr = (char __user *)cmsg + CMSG_COMPAT_ALIGN(cmsg_len);
112 	if ((unsigned long)(ptr + 1 - (char __user *)msg->msg_control) >
113 			msg->msg_controllen)
114 		return NULL;
115 	return (struct compat_cmsghdr __user *)ptr;
116 }
117 
118 /* There is a lot of hair here because the alignment rules (and
119  * thus placement) of cmsg headers and length are different for
120  * 32-bit apps.  -DaveM
121  */
122 int cmsghdr_from_user_compat_to_kern(struct msghdr *kmsg, struct sock *sk,
123 			       unsigned char *stackbuf, int stackbuf_size)
124 {
125 	struct compat_cmsghdr __user *ucmsg;
126 	struct cmsghdr *kcmsg, *kcmsg_base;
127 	compat_size_t ucmlen;
128 	__kernel_size_t kcmlen, tmp;
129 	int err = -EFAULT;
130 
131 	BUILD_BUG_ON(sizeof(struct compat_cmsghdr) !=
132 		     CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)));
133 
134 	kcmlen = 0;
135 	kcmsg_base = kcmsg = (struct cmsghdr *)stackbuf;
136 	ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
137 	while (ucmsg != NULL) {
138 		if (get_user(ucmlen, &ucmsg->cmsg_len))
139 			return -EFAULT;
140 
141 		/* Catch bogons. */
142 		if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
143 			return -EINVAL;
144 
145 		tmp = ((ucmlen - sizeof(*ucmsg)) + sizeof(struct cmsghdr));
146 		tmp = CMSG_ALIGN(tmp);
147 		kcmlen += tmp;
148 		ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
149 	}
150 	if (kcmlen == 0)
151 		return -EINVAL;
152 
153 	/* The kcmlen holds the 64-bit version of the control length.
154 	 * It may not be modified as we do not stick it into the kmsg
155 	 * until we have successfully copied over all of the data
156 	 * from the user.
157 	 */
158 	if (kcmlen > stackbuf_size)
159 		kcmsg_base = kcmsg = sock_kmalloc(sk, kcmlen, GFP_KERNEL);
160 	if (kcmsg == NULL)
161 		return -ENOBUFS;
162 
163 	/* Now copy them over neatly. */
164 	memset(kcmsg, 0, kcmlen);
165 	ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
166 	while (ucmsg != NULL) {
167 		if (__get_user(ucmlen, &ucmsg->cmsg_len))
168 			goto Efault;
169 		if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
170 			goto Einval;
171 		tmp = ((ucmlen - sizeof(*ucmsg)) + sizeof(struct cmsghdr));
172 		if ((char *)kcmsg_base + kcmlen - (char *)kcmsg < CMSG_ALIGN(tmp))
173 			goto Einval;
174 		kcmsg->cmsg_len = tmp;
175 		tmp = CMSG_ALIGN(tmp);
176 		if (__get_user(kcmsg->cmsg_level, &ucmsg->cmsg_level) ||
177 		    __get_user(kcmsg->cmsg_type, &ucmsg->cmsg_type) ||
178 		    copy_from_user(CMSG_DATA(kcmsg),
179 				   CMSG_COMPAT_DATA(ucmsg),
180 				   (ucmlen - sizeof(*ucmsg))))
181 			goto Efault;
182 
183 		/* Advance. */
184 		kcmsg = (struct cmsghdr *)((char *)kcmsg + tmp);
185 		ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
186 	}
187 
188 	/*
189 	 * check the length of messages copied in is the same as the
190 	 * what we get from the first loop
191 	 */
192 	if ((char *)kcmsg - (char *)kcmsg_base != kcmlen)
193 		goto Einval;
194 
195 	/* Ok, looks like we made it.  Hook it up and return success. */
196 	kmsg->msg_control = kcmsg_base;
197 	kmsg->msg_controllen = kcmlen;
198 	return 0;
199 
200 Einval:
201 	err = -EINVAL;
202 Efault:
203 	if (kcmsg_base != (struct cmsghdr *)stackbuf)
204 		sock_kfree_s(sk, kcmsg_base, kcmlen);
205 	return err;
206 }
207 
208 int put_cmsg_compat(struct msghdr *kmsg, int level, int type, int len, void *data)
209 {
210 	struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
211 	struct compat_cmsghdr cmhdr;
212 	struct compat_timeval ctv;
213 	struct compat_timespec cts[3];
214 	int cmlen;
215 
216 	if (cm == NULL || kmsg->msg_controllen < sizeof(*cm)) {
217 		kmsg->msg_flags |= MSG_CTRUNC;
218 		return 0; /* XXX: return error? check spec. */
219 	}
220 
221 	if (!COMPAT_USE_64BIT_TIME) {
222 		if (level == SOL_SOCKET && type == SCM_TIMESTAMP) {
223 			struct timeval *tv = (struct timeval *)data;
224 			ctv.tv_sec = tv->tv_sec;
225 			ctv.tv_usec = tv->tv_usec;
226 			data = &ctv;
227 			len = sizeof(ctv);
228 		}
229 		if (level == SOL_SOCKET &&
230 		    (type == SCM_TIMESTAMPNS || type == SCM_TIMESTAMPING)) {
231 			int count = type == SCM_TIMESTAMPNS ? 1 : 3;
232 			int i;
233 			struct timespec *ts = (struct timespec *)data;
234 			for (i = 0; i < count; i++) {
235 				cts[i].tv_sec = ts[i].tv_sec;
236 				cts[i].tv_nsec = ts[i].tv_nsec;
237 			}
238 			data = &cts;
239 			len = sizeof(cts[0]) * count;
240 		}
241 	}
242 
243 	cmlen = CMSG_COMPAT_LEN(len);
244 	if (kmsg->msg_controllen < cmlen) {
245 		kmsg->msg_flags |= MSG_CTRUNC;
246 		cmlen = kmsg->msg_controllen;
247 	}
248 	cmhdr.cmsg_level = level;
249 	cmhdr.cmsg_type = type;
250 	cmhdr.cmsg_len = cmlen;
251 
252 	if (copy_to_user(cm, &cmhdr, sizeof cmhdr))
253 		return -EFAULT;
254 	if (copy_to_user(CMSG_COMPAT_DATA(cm), data, cmlen - sizeof(struct compat_cmsghdr)))
255 		return -EFAULT;
256 	cmlen = CMSG_COMPAT_SPACE(len);
257 	if (kmsg->msg_controllen < cmlen)
258 		cmlen = kmsg->msg_controllen;
259 	kmsg->msg_control += cmlen;
260 	kmsg->msg_controllen -= cmlen;
261 	return 0;
262 }
263 
264 void scm_detach_fds_compat(struct msghdr *kmsg, struct scm_cookie *scm)
265 {
266 	struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
267 	int fdmax = (kmsg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int);
268 	int fdnum = scm->fp->count;
269 	struct file **fp = scm->fp->fp;
270 	int __user *cmfptr;
271 	int err = 0, i;
272 
273 	if (fdnum < fdmax)
274 		fdmax = fdnum;
275 
276 	for (i = 0, cmfptr = (int __user *) CMSG_COMPAT_DATA(cm); i < fdmax; i++, cmfptr++) {
277 		int new_fd;
278 		err = security_file_receive(fp[i]);
279 		if (err)
280 			break;
281 		err = get_unused_fd_flags(MSG_CMSG_CLOEXEC & kmsg->msg_flags
282 					  ? O_CLOEXEC : 0);
283 		if (err < 0)
284 			break;
285 		new_fd = err;
286 		err = put_user(new_fd, cmfptr);
287 		if (err) {
288 			put_unused_fd(new_fd);
289 			break;
290 		}
291 		/* Bump the usage count and install the file. */
292 		fd_install(new_fd, get_file(fp[i]));
293 	}
294 
295 	if (i > 0) {
296 		int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
297 		err = put_user(SOL_SOCKET, &cm->cmsg_level);
298 		if (!err)
299 			err = put_user(SCM_RIGHTS, &cm->cmsg_type);
300 		if (!err)
301 			err = put_user(cmlen, &cm->cmsg_len);
302 		if (!err) {
303 			cmlen = CMSG_COMPAT_SPACE(i * sizeof(int));
304 			kmsg->msg_control += cmlen;
305 			kmsg->msg_controllen -= cmlen;
306 		}
307 	}
308 	if (i < fdnum)
309 		kmsg->msg_flags |= MSG_CTRUNC;
310 
311 	/*
312 	 * All of the files that fit in the message have had their
313 	 * usage counts incremented, so we just free the list.
314 	 */
315 	__scm_destroy(scm);
316 }
317 
318 /* allocate a 64-bit sock_fprog on the user stack for duration of syscall. */
319 struct sock_fprog __user *get_compat_bpf_fprog(char __user *optval)
320 {
321 	struct compat_sock_fprog __user *fprog32 = (struct compat_sock_fprog __user *)optval;
322 	struct sock_fprog __user *kfprog = compat_alloc_user_space(sizeof(struct sock_fprog));
323 	struct compat_sock_fprog f32;
324 	struct sock_fprog f;
325 
326 	if (copy_from_user(&f32, fprog32, sizeof(*fprog32)))
327 		return NULL;
328 	memset(&f, 0, sizeof(f));
329 	f.len = f32.len;
330 	f.filter = compat_ptr(f32.filter);
331 	if (copy_to_user(kfprog, &f, sizeof(struct sock_fprog)))
332 		return NULL;
333 
334 	return kfprog;
335 }
336 EXPORT_SYMBOL_GPL(get_compat_bpf_fprog);
337 
338 static int do_set_attach_filter(struct socket *sock, int level, int optname,
339 				char __user *optval, unsigned int optlen)
340 {
341 	struct sock_fprog __user *kfprog;
342 
343 	kfprog = get_compat_bpf_fprog(optval);
344 	if (!kfprog)
345 		return -EFAULT;
346 
347 	return sock_setsockopt(sock, level, optname, (char __user *)kfprog,
348 			      sizeof(struct sock_fprog));
349 }
350 
351 static int do_set_sock_timeout(struct socket *sock, int level,
352 		int optname, char __user *optval, unsigned int optlen)
353 {
354 	struct compat_timeval __user *up = (struct compat_timeval __user *)optval;
355 	struct timeval ktime;
356 	mm_segment_t old_fs;
357 	int err;
358 
359 	if (optlen < sizeof(*up))
360 		return -EINVAL;
361 	if (!access_ok(up, sizeof(*up)) ||
362 	    __get_user(ktime.tv_sec, &up->tv_sec) ||
363 	    __get_user(ktime.tv_usec, &up->tv_usec))
364 		return -EFAULT;
365 	old_fs = get_fs();
366 	set_fs(KERNEL_DS);
367 	err = sock_setsockopt(sock, level, optname, (char *)&ktime, sizeof(ktime));
368 	set_fs(old_fs);
369 
370 	return err;
371 }
372 
373 static int compat_sock_setsockopt(struct socket *sock, int level, int optname,
374 				char __user *optval, unsigned int optlen)
375 {
376 	if (optname == SO_ATTACH_FILTER ||
377 	    optname == SO_ATTACH_REUSEPORT_CBPF)
378 		return do_set_attach_filter(sock, level, optname,
379 					    optval, optlen);
380 	if (!COMPAT_USE_64BIT_TIME &&
381 	    (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO))
382 		return do_set_sock_timeout(sock, level, optname, optval, optlen);
383 
384 	return sock_setsockopt(sock, level, optname, optval, optlen);
385 }
386 
387 static int __compat_sys_setsockopt(int fd, int level, int optname,
388 				   char __user *optval, unsigned int optlen)
389 {
390 	int err;
391 	struct socket *sock;
392 
393 	if (optlen > INT_MAX)
394 		return -EINVAL;
395 
396 	sock = sockfd_lookup(fd, &err);
397 	if (sock) {
398 		err = security_socket_setsockopt(sock, level, optname);
399 		if (err) {
400 			sockfd_put(sock);
401 			return err;
402 		}
403 
404 		if (level == SOL_SOCKET)
405 			err = compat_sock_setsockopt(sock, level,
406 					optname, optval, optlen);
407 		else if (sock->ops->compat_setsockopt)
408 			err = sock->ops->compat_setsockopt(sock, level,
409 					optname, optval, optlen);
410 		else
411 			err = sock->ops->setsockopt(sock, level,
412 					optname, optval, optlen);
413 		sockfd_put(sock);
414 	}
415 	return err;
416 }
417 
418 COMPAT_SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
419 		       char __user *, optval, unsigned int, optlen)
420 {
421 	return __compat_sys_setsockopt(fd, level, optname, optval, optlen);
422 }
423 
424 static int do_get_sock_timeout(struct socket *sock, int level, int optname,
425 		char __user *optval, int __user *optlen)
426 {
427 	struct compat_timeval __user *up;
428 	struct timeval ktime;
429 	mm_segment_t old_fs;
430 	int len, err;
431 
432 	up = (struct compat_timeval __user *) optval;
433 	if (get_user(len, optlen))
434 		return -EFAULT;
435 	if (len < sizeof(*up))
436 		return -EINVAL;
437 	len = sizeof(ktime);
438 	old_fs = get_fs();
439 	set_fs(KERNEL_DS);
440 	err = sock_getsockopt(sock, level, optname, (char *) &ktime, &len);
441 	set_fs(old_fs);
442 
443 	if (!err) {
444 		if (put_user(sizeof(*up), optlen) ||
445 		    !access_ok(up, sizeof(*up)) ||
446 		    __put_user(ktime.tv_sec, &up->tv_sec) ||
447 		    __put_user(ktime.tv_usec, &up->tv_usec))
448 			err = -EFAULT;
449 	}
450 	return err;
451 }
452 
453 static int compat_sock_getsockopt(struct socket *sock, int level, int optname,
454 				char __user *optval, int __user *optlen)
455 {
456 	if (!COMPAT_USE_64BIT_TIME &&
457 	    (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO))
458 		return do_get_sock_timeout(sock, level, optname, optval, optlen);
459 	return sock_getsockopt(sock, level, optname, optval, optlen);
460 }
461 
462 int compat_sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
463 {
464 	struct compat_timeval __user *ctv;
465 	int err;
466 	struct timeval tv;
467 
468 	if (COMPAT_USE_64BIT_TIME)
469 		return sock_get_timestamp(sk, userstamp);
470 
471 	ctv = (struct compat_timeval __user *) userstamp;
472 	err = -ENOENT;
473 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
474 	tv = ktime_to_timeval(sock_read_timestamp(sk));
475 
476 	if (tv.tv_sec == -1)
477 		return err;
478 	if (tv.tv_sec == 0) {
479 		ktime_t kt = ktime_get_real();
480 		sock_write_timestamp(sk, kt);
481 		tv = ktime_to_timeval(kt);
482 	}
483 	err = 0;
484 	if (put_user(tv.tv_sec, &ctv->tv_sec) ||
485 			put_user(tv.tv_usec, &ctv->tv_usec))
486 		err = -EFAULT;
487 	return err;
488 }
489 EXPORT_SYMBOL(compat_sock_get_timestamp);
490 
491 int compat_sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
492 {
493 	struct compat_timespec __user *ctv;
494 	int err;
495 	struct timespec ts;
496 
497 	if (COMPAT_USE_64BIT_TIME)
498 		return sock_get_timestampns (sk, userstamp);
499 
500 	ctv = (struct compat_timespec __user *) userstamp;
501 	err = -ENOENT;
502 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
503 	ts = ktime_to_timespec(sock_read_timestamp(sk));
504 	if (ts.tv_sec == -1)
505 		return err;
506 	if (ts.tv_sec == 0) {
507 		ktime_t kt = ktime_get_real();
508 		sock_write_timestamp(sk, kt);
509 		ts = ktime_to_timespec(kt);
510 	}
511 	err = 0;
512 	if (put_user(ts.tv_sec, &ctv->tv_sec) ||
513 			put_user(ts.tv_nsec, &ctv->tv_nsec))
514 		err = -EFAULT;
515 	return err;
516 }
517 EXPORT_SYMBOL(compat_sock_get_timestampns);
518 
519 static int __compat_sys_getsockopt(int fd, int level, int optname,
520 				   char __user *optval,
521 				   int __user *optlen)
522 {
523 	int err;
524 	struct socket *sock = sockfd_lookup(fd, &err);
525 
526 	if (sock) {
527 		err = security_socket_getsockopt(sock, level, optname);
528 		if (err) {
529 			sockfd_put(sock);
530 			return err;
531 		}
532 
533 		if (level == SOL_SOCKET)
534 			err = compat_sock_getsockopt(sock, level,
535 					optname, optval, optlen);
536 		else if (sock->ops->compat_getsockopt)
537 			err = sock->ops->compat_getsockopt(sock, level,
538 					optname, optval, optlen);
539 		else
540 			err = sock->ops->getsockopt(sock, level,
541 					optname, optval, optlen);
542 		sockfd_put(sock);
543 	}
544 	return err;
545 }
546 
547 COMPAT_SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname,
548 		       char __user *, optval, int __user *, optlen)
549 {
550 	return __compat_sys_getsockopt(fd, level, optname, optval, optlen);
551 }
552 
553 struct compat_group_req {
554 	__u32				 gr_interface;
555 	struct __kernel_sockaddr_storage gr_group
556 		__aligned(4);
557 } __packed;
558 
559 struct compat_group_source_req {
560 	__u32				 gsr_interface;
561 	struct __kernel_sockaddr_storage gsr_group
562 		__aligned(4);
563 	struct __kernel_sockaddr_storage gsr_source
564 		__aligned(4);
565 } __packed;
566 
567 struct compat_group_filter {
568 	__u32				 gf_interface;
569 	struct __kernel_sockaddr_storage gf_group
570 		__aligned(4);
571 	__u32				 gf_fmode;
572 	__u32				 gf_numsrc;
573 	struct __kernel_sockaddr_storage gf_slist[1]
574 		__aligned(4);
575 } __packed;
576 
577 #define __COMPAT_GF0_SIZE (sizeof(struct compat_group_filter) - \
578 			sizeof(struct __kernel_sockaddr_storage))
579 
580 
581 int compat_mc_setsockopt(struct sock *sock, int level, int optname,
582 	char __user *optval, unsigned int optlen,
583 	int (*setsockopt)(struct sock *, int, int, char __user *, unsigned int))
584 {
585 	char __user	*koptval = optval;
586 	int		koptlen = optlen;
587 
588 	switch (optname) {
589 	case MCAST_JOIN_GROUP:
590 	case MCAST_LEAVE_GROUP:
591 	{
592 		struct compat_group_req __user *gr32 = (void *)optval;
593 		struct group_req __user *kgr =
594 			compat_alloc_user_space(sizeof(struct group_req));
595 		u32 interface;
596 
597 		if (!access_ok(gr32, sizeof(*gr32)) ||
598 		    !access_ok(kgr, sizeof(struct group_req)) ||
599 		    __get_user(interface, &gr32->gr_interface) ||
600 		    __put_user(interface, &kgr->gr_interface) ||
601 		    copy_in_user(&kgr->gr_group, &gr32->gr_group,
602 				sizeof(kgr->gr_group)))
603 			return -EFAULT;
604 		koptval = (char __user *)kgr;
605 		koptlen = sizeof(struct group_req);
606 		break;
607 	}
608 	case MCAST_JOIN_SOURCE_GROUP:
609 	case MCAST_LEAVE_SOURCE_GROUP:
610 	case MCAST_BLOCK_SOURCE:
611 	case MCAST_UNBLOCK_SOURCE:
612 	{
613 		struct compat_group_source_req __user *gsr32 = (void *)optval;
614 		struct group_source_req __user *kgsr = compat_alloc_user_space(
615 			sizeof(struct group_source_req));
616 		u32 interface;
617 
618 		if (!access_ok(gsr32, sizeof(*gsr32)) ||
619 		    !access_ok(kgsr,
620 			sizeof(struct group_source_req)) ||
621 		    __get_user(interface, &gsr32->gsr_interface) ||
622 		    __put_user(interface, &kgsr->gsr_interface) ||
623 		    copy_in_user(&kgsr->gsr_group, &gsr32->gsr_group,
624 				sizeof(kgsr->gsr_group)) ||
625 		    copy_in_user(&kgsr->gsr_source, &gsr32->gsr_source,
626 				sizeof(kgsr->gsr_source)))
627 			return -EFAULT;
628 		koptval = (char __user *)kgsr;
629 		koptlen = sizeof(struct group_source_req);
630 		break;
631 	}
632 	case MCAST_MSFILTER:
633 	{
634 		struct compat_group_filter __user *gf32 = (void *)optval;
635 		struct group_filter __user *kgf;
636 		u32 interface, fmode, numsrc;
637 
638 		if (!access_ok(gf32, __COMPAT_GF0_SIZE) ||
639 		    __get_user(interface, &gf32->gf_interface) ||
640 		    __get_user(fmode, &gf32->gf_fmode) ||
641 		    __get_user(numsrc, &gf32->gf_numsrc))
642 			return -EFAULT;
643 		koptlen = optlen + sizeof(struct group_filter) -
644 				sizeof(struct compat_group_filter);
645 		if (koptlen < GROUP_FILTER_SIZE(numsrc))
646 			return -EINVAL;
647 		kgf = compat_alloc_user_space(koptlen);
648 		if (!access_ok(kgf, koptlen) ||
649 		    __put_user(interface, &kgf->gf_interface) ||
650 		    __put_user(fmode, &kgf->gf_fmode) ||
651 		    __put_user(numsrc, &kgf->gf_numsrc) ||
652 		    copy_in_user(&kgf->gf_group, &gf32->gf_group,
653 				sizeof(kgf->gf_group)) ||
654 		    (numsrc && copy_in_user(kgf->gf_slist, gf32->gf_slist,
655 				numsrc * sizeof(kgf->gf_slist[0]))))
656 			return -EFAULT;
657 		koptval = (char __user *)kgf;
658 		break;
659 	}
660 
661 	default:
662 		break;
663 	}
664 	return setsockopt(sock, level, optname, koptval, koptlen);
665 }
666 EXPORT_SYMBOL(compat_mc_setsockopt);
667 
668 int compat_mc_getsockopt(struct sock *sock, int level, int optname,
669 	char __user *optval, int __user *optlen,
670 	int (*getsockopt)(struct sock *, int, int, char __user *, int __user *))
671 {
672 	struct compat_group_filter __user *gf32 = (void *)optval;
673 	struct group_filter __user *kgf;
674 	int __user	*koptlen;
675 	u32 interface, fmode, numsrc;
676 	int klen, ulen, err;
677 
678 	if (optname != MCAST_MSFILTER)
679 		return getsockopt(sock, level, optname, optval, optlen);
680 
681 	koptlen = compat_alloc_user_space(sizeof(*koptlen));
682 	if (!access_ok(optlen, sizeof(*optlen)) ||
683 	    __get_user(ulen, optlen))
684 		return -EFAULT;
685 
686 	/* adjust len for pad */
687 	klen = ulen + sizeof(*kgf) - sizeof(*gf32);
688 
689 	if (klen < GROUP_FILTER_SIZE(0))
690 		return -EINVAL;
691 
692 	if (!access_ok(koptlen, sizeof(*koptlen)) ||
693 	    __put_user(klen, koptlen))
694 		return -EFAULT;
695 
696 	/* have to allow space for previous compat_alloc_user_space, too */
697 	kgf = compat_alloc_user_space(klen+sizeof(*optlen));
698 
699 	if (!access_ok(gf32, __COMPAT_GF0_SIZE) ||
700 	    __get_user(interface, &gf32->gf_interface) ||
701 	    __get_user(fmode, &gf32->gf_fmode) ||
702 	    __get_user(numsrc, &gf32->gf_numsrc) ||
703 	    __put_user(interface, &kgf->gf_interface) ||
704 	    __put_user(fmode, &kgf->gf_fmode) ||
705 	    __put_user(numsrc, &kgf->gf_numsrc) ||
706 	    copy_in_user(&kgf->gf_group, &gf32->gf_group, sizeof(kgf->gf_group)))
707 		return -EFAULT;
708 
709 	err = getsockopt(sock, level, optname, (char __user *)kgf, koptlen);
710 	if (err)
711 		return err;
712 
713 	if (!access_ok(koptlen, sizeof(*koptlen)) ||
714 	    __get_user(klen, koptlen))
715 		return -EFAULT;
716 
717 	ulen = klen - (sizeof(*kgf)-sizeof(*gf32));
718 
719 	if (!access_ok(optlen, sizeof(*optlen)) ||
720 	    __put_user(ulen, optlen))
721 		return -EFAULT;
722 
723 	if (!access_ok(kgf, klen) ||
724 	    !access_ok(gf32, ulen) ||
725 	    __get_user(interface, &kgf->gf_interface) ||
726 	    __get_user(fmode, &kgf->gf_fmode) ||
727 	    __get_user(numsrc, &kgf->gf_numsrc) ||
728 	    __put_user(interface, &gf32->gf_interface) ||
729 	    __put_user(fmode, &gf32->gf_fmode) ||
730 	    __put_user(numsrc, &gf32->gf_numsrc))
731 		return -EFAULT;
732 	if (numsrc) {
733 		int copylen;
734 
735 		klen -= GROUP_FILTER_SIZE(0);
736 		copylen = numsrc * sizeof(gf32->gf_slist[0]);
737 		if (copylen > klen)
738 			copylen = klen;
739 		if (copy_in_user(gf32->gf_slist, kgf->gf_slist, copylen))
740 			return -EFAULT;
741 	}
742 	return err;
743 }
744 EXPORT_SYMBOL(compat_mc_getsockopt);
745 
746 
747 /* Argument list sizes for compat_sys_socketcall */
748 #define AL(x) ((x) * sizeof(u32))
749 static unsigned char nas[21] = {
750 	AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
751 	AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
752 	AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
753 	AL(4), AL(5), AL(4)
754 };
755 #undef AL
756 
757 static inline long __compat_sys_sendmsg(int fd,
758 					struct compat_msghdr __user *msg,
759 					unsigned int flags)
760 {
761 	return __sys_sendmsg(fd, (struct user_msghdr __user *)msg,
762 			     flags | MSG_CMSG_COMPAT, false);
763 }
764 
765 COMPAT_SYSCALL_DEFINE3(sendmsg, int, fd, struct compat_msghdr __user *, msg,
766 		       unsigned int, flags)
767 {
768 	return __compat_sys_sendmsg(fd, msg, flags);
769 }
770 
771 static inline long __compat_sys_sendmmsg(int fd,
772 					 struct compat_mmsghdr __user *mmsg,
773 					 unsigned int vlen, unsigned int flags)
774 {
775 	return __sys_sendmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
776 			      flags | MSG_CMSG_COMPAT, false);
777 }
778 
779 COMPAT_SYSCALL_DEFINE4(sendmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
780 		       unsigned int, vlen, unsigned int, flags)
781 {
782 	return __compat_sys_sendmmsg(fd, mmsg, vlen, flags);
783 }
784 
785 static inline long __compat_sys_recvmsg(int fd,
786 					struct compat_msghdr __user *msg,
787 					unsigned int flags)
788 {
789 	return __sys_recvmsg(fd, (struct user_msghdr __user *)msg,
790 			     flags | MSG_CMSG_COMPAT, false);
791 }
792 
793 COMPAT_SYSCALL_DEFINE3(recvmsg, int, fd, struct compat_msghdr __user *, msg,
794 		       unsigned int, flags)
795 {
796 	return __compat_sys_recvmsg(fd, msg, flags);
797 }
798 
799 static inline long __compat_sys_recvfrom(int fd, void __user *buf,
800 					 compat_size_t len, unsigned int flags,
801 					 struct sockaddr __user *addr,
802 					 int __user *addrlen)
803 {
804 	return __sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr,
805 			      addrlen);
806 }
807 
808 COMPAT_SYSCALL_DEFINE4(recv, int, fd, void __user *, buf, compat_size_t, len, unsigned int, flags)
809 {
810 	return __compat_sys_recvfrom(fd, buf, len, flags, NULL, NULL);
811 }
812 
813 COMPAT_SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, buf, compat_size_t, len,
814 		       unsigned int, flags, struct sockaddr __user *, addr,
815 		       int __user *, addrlen)
816 {
817 	return __compat_sys_recvfrom(fd, buf, len, flags, addr, addrlen);
818 }
819 
820 COMPAT_SYSCALL_DEFINE5(recvmmsg_time64, int, fd, struct compat_mmsghdr __user *, mmsg,
821 		       unsigned int, vlen, unsigned int, flags,
822 		       struct __kernel_timespec __user *, timeout)
823 {
824 	return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
825 			      flags | MSG_CMSG_COMPAT, timeout, NULL);
826 }
827 
828 #ifdef CONFIG_COMPAT_32BIT_TIME
829 COMPAT_SYSCALL_DEFINE5(recvmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
830 		       unsigned int, vlen, unsigned int, flags,
831 		       struct old_timespec32 __user *, timeout)
832 {
833 	return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
834 			      flags | MSG_CMSG_COMPAT, NULL, timeout);
835 }
836 #endif
837 
838 COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args)
839 {
840 	u32 a[AUDITSC_ARGS];
841 	unsigned int len;
842 	u32 a0, a1;
843 	int ret;
844 
845 	if (call < SYS_SOCKET || call > SYS_SENDMMSG)
846 		return -EINVAL;
847 	len = nas[call];
848 	if (len > sizeof(a))
849 		return -EINVAL;
850 
851 	if (copy_from_user(a, args, len))
852 		return -EFAULT;
853 
854 	ret = audit_socketcall_compat(len / sizeof(a[0]), a);
855 	if (ret)
856 		return ret;
857 
858 	a0 = a[0];
859 	a1 = a[1];
860 
861 	switch (call) {
862 	case SYS_SOCKET:
863 		ret = __sys_socket(a0, a1, a[2]);
864 		break;
865 	case SYS_BIND:
866 		ret = __sys_bind(a0, compat_ptr(a1), a[2]);
867 		break;
868 	case SYS_CONNECT:
869 		ret = __sys_connect(a0, compat_ptr(a1), a[2]);
870 		break;
871 	case SYS_LISTEN:
872 		ret = __sys_listen(a0, a1);
873 		break;
874 	case SYS_ACCEPT:
875 		ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0);
876 		break;
877 	case SYS_GETSOCKNAME:
878 		ret = __sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]));
879 		break;
880 	case SYS_GETPEERNAME:
881 		ret = __sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2]));
882 		break;
883 	case SYS_SOCKETPAIR:
884 		ret = __sys_socketpair(a0, a1, a[2], compat_ptr(a[3]));
885 		break;
886 	case SYS_SEND:
887 		ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3], NULL, 0);
888 		break;
889 	case SYS_SENDTO:
890 		ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3],
891 				   compat_ptr(a[4]), a[5]);
892 		break;
893 	case SYS_RECV:
894 		ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
895 					    NULL, NULL);
896 		break;
897 	case SYS_RECVFROM:
898 		ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
899 					    compat_ptr(a[4]),
900 					    compat_ptr(a[5]));
901 		break;
902 	case SYS_SHUTDOWN:
903 		ret = __sys_shutdown(a0, a1);
904 		break;
905 	case SYS_SETSOCKOPT:
906 		ret = __compat_sys_setsockopt(a0, a1, a[2],
907 					      compat_ptr(a[3]), a[4]);
908 		break;
909 	case SYS_GETSOCKOPT:
910 		ret = __compat_sys_getsockopt(a0, a1, a[2],
911 					      compat_ptr(a[3]),
912 					      compat_ptr(a[4]));
913 		break;
914 	case SYS_SENDMSG:
915 		ret = __compat_sys_sendmsg(a0, compat_ptr(a1), a[2]);
916 		break;
917 	case SYS_SENDMMSG:
918 		ret = __compat_sys_sendmmsg(a0, compat_ptr(a1), a[2], a[3]);
919 		break;
920 	case SYS_RECVMSG:
921 		ret = __compat_sys_recvmsg(a0, compat_ptr(a1), a[2]);
922 		break;
923 	case SYS_RECVMMSG:
924 		ret = __sys_recvmmsg(a0, compat_ptr(a1), a[2],
925 				     a[3] | MSG_CMSG_COMPAT, NULL,
926 				     compat_ptr(a[4]));
927 		break;
928 	case SYS_ACCEPT4:
929 		ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]);
930 		break;
931 	default:
932 		ret = -EINVAL;
933 		break;
934 	}
935 	return ret;
936 }
937