xref: /linux/net/compat.c (revision 5ff328836dfde0cef9f28c8b8791a90a36d7a183)
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 = sockfd_lookup(fd, &err);
392 
393 	if (sock) {
394 		err = security_socket_setsockopt(sock, level, optname);
395 		if (err) {
396 			sockfd_put(sock);
397 			return err;
398 		}
399 
400 		if (level == SOL_SOCKET)
401 			err = compat_sock_setsockopt(sock, level,
402 					optname, optval, optlen);
403 		else if (sock->ops->compat_setsockopt)
404 			err = sock->ops->compat_setsockopt(sock, level,
405 					optname, optval, optlen);
406 		else
407 			err = sock->ops->setsockopt(sock, level,
408 					optname, optval, optlen);
409 		sockfd_put(sock);
410 	}
411 	return err;
412 }
413 
414 COMPAT_SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
415 		       char __user *, optval, unsigned int, optlen)
416 {
417 	return __compat_sys_setsockopt(fd, level, optname, optval, optlen);
418 }
419 
420 static int do_get_sock_timeout(struct socket *sock, int level, int optname,
421 		char __user *optval, int __user *optlen)
422 {
423 	struct compat_timeval __user *up;
424 	struct timeval ktime;
425 	mm_segment_t old_fs;
426 	int len, err;
427 
428 	up = (struct compat_timeval __user *) optval;
429 	if (get_user(len, optlen))
430 		return -EFAULT;
431 	if (len < sizeof(*up))
432 		return -EINVAL;
433 	len = sizeof(ktime);
434 	old_fs = get_fs();
435 	set_fs(KERNEL_DS);
436 	err = sock_getsockopt(sock, level, optname, (char *) &ktime, &len);
437 	set_fs(old_fs);
438 
439 	if (!err) {
440 		if (put_user(sizeof(*up), optlen) ||
441 		    !access_ok(up, sizeof(*up)) ||
442 		    __put_user(ktime.tv_sec, &up->tv_sec) ||
443 		    __put_user(ktime.tv_usec, &up->tv_usec))
444 			err = -EFAULT;
445 	}
446 	return err;
447 }
448 
449 static int compat_sock_getsockopt(struct socket *sock, int level, int optname,
450 				char __user *optval, int __user *optlen)
451 {
452 	if (!COMPAT_USE_64BIT_TIME &&
453 	    (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO))
454 		return do_get_sock_timeout(sock, level, optname, optval, optlen);
455 	return sock_getsockopt(sock, level, optname, optval, optlen);
456 }
457 
458 int compat_sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
459 {
460 	struct compat_timeval __user *ctv;
461 	int err;
462 	struct timeval tv;
463 
464 	if (COMPAT_USE_64BIT_TIME)
465 		return sock_get_timestamp(sk, userstamp);
466 
467 	ctv = (struct compat_timeval __user *) userstamp;
468 	err = -ENOENT;
469 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
470 	tv = ktime_to_timeval(sock_read_timestamp(sk));
471 
472 	if (tv.tv_sec == -1)
473 		return err;
474 	if (tv.tv_sec == 0) {
475 		ktime_t kt = ktime_get_real();
476 		sock_write_timestamp(sk, kt);
477 		tv = ktime_to_timeval(kt);
478 	}
479 	err = 0;
480 	if (put_user(tv.tv_sec, &ctv->tv_sec) ||
481 			put_user(tv.tv_usec, &ctv->tv_usec))
482 		err = -EFAULT;
483 	return err;
484 }
485 EXPORT_SYMBOL(compat_sock_get_timestamp);
486 
487 int compat_sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
488 {
489 	struct compat_timespec __user *ctv;
490 	int err;
491 	struct timespec ts;
492 
493 	if (COMPAT_USE_64BIT_TIME)
494 		return sock_get_timestampns (sk, userstamp);
495 
496 	ctv = (struct compat_timespec __user *) userstamp;
497 	err = -ENOENT;
498 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
499 	ts = ktime_to_timespec(sock_read_timestamp(sk));
500 	if (ts.tv_sec == -1)
501 		return err;
502 	if (ts.tv_sec == 0) {
503 		ktime_t kt = ktime_get_real();
504 		sock_write_timestamp(sk, kt);
505 		ts = ktime_to_timespec(kt);
506 	}
507 	err = 0;
508 	if (put_user(ts.tv_sec, &ctv->tv_sec) ||
509 			put_user(ts.tv_nsec, &ctv->tv_nsec))
510 		err = -EFAULT;
511 	return err;
512 }
513 EXPORT_SYMBOL(compat_sock_get_timestampns);
514 
515 static int __compat_sys_getsockopt(int fd, int level, int optname,
516 				   char __user *optval,
517 				   int __user *optlen)
518 {
519 	int err;
520 	struct socket *sock = sockfd_lookup(fd, &err);
521 
522 	if (sock) {
523 		err = security_socket_getsockopt(sock, level, optname);
524 		if (err) {
525 			sockfd_put(sock);
526 			return err;
527 		}
528 
529 		if (level == SOL_SOCKET)
530 			err = compat_sock_getsockopt(sock, level,
531 					optname, optval, optlen);
532 		else if (sock->ops->compat_getsockopt)
533 			err = sock->ops->compat_getsockopt(sock, level,
534 					optname, optval, optlen);
535 		else
536 			err = sock->ops->getsockopt(sock, level,
537 					optname, optval, optlen);
538 		sockfd_put(sock);
539 	}
540 	return err;
541 }
542 
543 COMPAT_SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname,
544 		       char __user *, optval, int __user *, optlen)
545 {
546 	return __compat_sys_getsockopt(fd, level, optname, optval, optlen);
547 }
548 
549 struct compat_group_req {
550 	__u32				 gr_interface;
551 	struct __kernel_sockaddr_storage gr_group
552 		__aligned(4);
553 } __packed;
554 
555 struct compat_group_source_req {
556 	__u32				 gsr_interface;
557 	struct __kernel_sockaddr_storage gsr_group
558 		__aligned(4);
559 	struct __kernel_sockaddr_storage gsr_source
560 		__aligned(4);
561 } __packed;
562 
563 struct compat_group_filter {
564 	__u32				 gf_interface;
565 	struct __kernel_sockaddr_storage gf_group
566 		__aligned(4);
567 	__u32				 gf_fmode;
568 	__u32				 gf_numsrc;
569 	struct __kernel_sockaddr_storage gf_slist[1]
570 		__aligned(4);
571 } __packed;
572 
573 #define __COMPAT_GF0_SIZE (sizeof(struct compat_group_filter) - \
574 			sizeof(struct __kernel_sockaddr_storage))
575 
576 
577 int compat_mc_setsockopt(struct sock *sock, int level, int optname,
578 	char __user *optval, unsigned int optlen,
579 	int (*setsockopt)(struct sock *, int, int, char __user *, unsigned int))
580 {
581 	char __user	*koptval = optval;
582 	int		koptlen = optlen;
583 
584 	switch (optname) {
585 	case MCAST_JOIN_GROUP:
586 	case MCAST_LEAVE_GROUP:
587 	{
588 		struct compat_group_req __user *gr32 = (void *)optval;
589 		struct group_req __user *kgr =
590 			compat_alloc_user_space(sizeof(struct group_req));
591 		u32 interface;
592 
593 		if (!access_ok(gr32, sizeof(*gr32)) ||
594 		    !access_ok(kgr, sizeof(struct group_req)) ||
595 		    __get_user(interface, &gr32->gr_interface) ||
596 		    __put_user(interface, &kgr->gr_interface) ||
597 		    copy_in_user(&kgr->gr_group, &gr32->gr_group,
598 				sizeof(kgr->gr_group)))
599 			return -EFAULT;
600 		koptval = (char __user *)kgr;
601 		koptlen = sizeof(struct group_req);
602 		break;
603 	}
604 	case MCAST_JOIN_SOURCE_GROUP:
605 	case MCAST_LEAVE_SOURCE_GROUP:
606 	case MCAST_BLOCK_SOURCE:
607 	case MCAST_UNBLOCK_SOURCE:
608 	{
609 		struct compat_group_source_req __user *gsr32 = (void *)optval;
610 		struct group_source_req __user *kgsr = compat_alloc_user_space(
611 			sizeof(struct group_source_req));
612 		u32 interface;
613 
614 		if (!access_ok(gsr32, sizeof(*gsr32)) ||
615 		    !access_ok(kgsr,
616 			sizeof(struct group_source_req)) ||
617 		    __get_user(interface, &gsr32->gsr_interface) ||
618 		    __put_user(interface, &kgsr->gsr_interface) ||
619 		    copy_in_user(&kgsr->gsr_group, &gsr32->gsr_group,
620 				sizeof(kgsr->gsr_group)) ||
621 		    copy_in_user(&kgsr->gsr_source, &gsr32->gsr_source,
622 				sizeof(kgsr->gsr_source)))
623 			return -EFAULT;
624 		koptval = (char __user *)kgsr;
625 		koptlen = sizeof(struct group_source_req);
626 		break;
627 	}
628 	case MCAST_MSFILTER:
629 	{
630 		struct compat_group_filter __user *gf32 = (void *)optval;
631 		struct group_filter __user *kgf;
632 		u32 interface, fmode, numsrc;
633 
634 		if (!access_ok(gf32, __COMPAT_GF0_SIZE) ||
635 		    __get_user(interface, &gf32->gf_interface) ||
636 		    __get_user(fmode, &gf32->gf_fmode) ||
637 		    __get_user(numsrc, &gf32->gf_numsrc))
638 			return -EFAULT;
639 		koptlen = optlen + sizeof(struct group_filter) -
640 				sizeof(struct compat_group_filter);
641 		if (koptlen < GROUP_FILTER_SIZE(numsrc))
642 			return -EINVAL;
643 		kgf = compat_alloc_user_space(koptlen);
644 		if (!access_ok(kgf, koptlen) ||
645 		    __put_user(interface, &kgf->gf_interface) ||
646 		    __put_user(fmode, &kgf->gf_fmode) ||
647 		    __put_user(numsrc, &kgf->gf_numsrc) ||
648 		    copy_in_user(&kgf->gf_group, &gf32->gf_group,
649 				sizeof(kgf->gf_group)) ||
650 		    (numsrc && copy_in_user(kgf->gf_slist, gf32->gf_slist,
651 				numsrc * sizeof(kgf->gf_slist[0]))))
652 			return -EFAULT;
653 		koptval = (char __user *)kgf;
654 		break;
655 	}
656 
657 	default:
658 		break;
659 	}
660 	return setsockopt(sock, level, optname, koptval, koptlen);
661 }
662 EXPORT_SYMBOL(compat_mc_setsockopt);
663 
664 int compat_mc_getsockopt(struct sock *sock, int level, int optname,
665 	char __user *optval, int __user *optlen,
666 	int (*getsockopt)(struct sock *, int, int, char __user *, int __user *))
667 {
668 	struct compat_group_filter __user *gf32 = (void *)optval;
669 	struct group_filter __user *kgf;
670 	int __user	*koptlen;
671 	u32 interface, fmode, numsrc;
672 	int klen, ulen, err;
673 
674 	if (optname != MCAST_MSFILTER)
675 		return getsockopt(sock, level, optname, optval, optlen);
676 
677 	koptlen = compat_alloc_user_space(sizeof(*koptlen));
678 	if (!access_ok(optlen, sizeof(*optlen)) ||
679 	    __get_user(ulen, optlen))
680 		return -EFAULT;
681 
682 	/* adjust len for pad */
683 	klen = ulen + sizeof(*kgf) - sizeof(*gf32);
684 
685 	if (klen < GROUP_FILTER_SIZE(0))
686 		return -EINVAL;
687 
688 	if (!access_ok(koptlen, sizeof(*koptlen)) ||
689 	    __put_user(klen, koptlen))
690 		return -EFAULT;
691 
692 	/* have to allow space for previous compat_alloc_user_space, too */
693 	kgf = compat_alloc_user_space(klen+sizeof(*optlen));
694 
695 	if (!access_ok(gf32, __COMPAT_GF0_SIZE) ||
696 	    __get_user(interface, &gf32->gf_interface) ||
697 	    __get_user(fmode, &gf32->gf_fmode) ||
698 	    __get_user(numsrc, &gf32->gf_numsrc) ||
699 	    __put_user(interface, &kgf->gf_interface) ||
700 	    __put_user(fmode, &kgf->gf_fmode) ||
701 	    __put_user(numsrc, &kgf->gf_numsrc) ||
702 	    copy_in_user(&kgf->gf_group, &gf32->gf_group, sizeof(kgf->gf_group)))
703 		return -EFAULT;
704 
705 	err = getsockopt(sock, level, optname, (char __user *)kgf, koptlen);
706 	if (err)
707 		return err;
708 
709 	if (!access_ok(koptlen, sizeof(*koptlen)) ||
710 	    __get_user(klen, koptlen))
711 		return -EFAULT;
712 
713 	ulen = klen - (sizeof(*kgf)-sizeof(*gf32));
714 
715 	if (!access_ok(optlen, sizeof(*optlen)) ||
716 	    __put_user(ulen, optlen))
717 		return -EFAULT;
718 
719 	if (!access_ok(kgf, klen) ||
720 	    !access_ok(gf32, ulen) ||
721 	    __get_user(interface, &kgf->gf_interface) ||
722 	    __get_user(fmode, &kgf->gf_fmode) ||
723 	    __get_user(numsrc, &kgf->gf_numsrc) ||
724 	    __put_user(interface, &gf32->gf_interface) ||
725 	    __put_user(fmode, &gf32->gf_fmode) ||
726 	    __put_user(numsrc, &gf32->gf_numsrc))
727 		return -EFAULT;
728 	if (numsrc) {
729 		int copylen;
730 
731 		klen -= GROUP_FILTER_SIZE(0);
732 		copylen = numsrc * sizeof(gf32->gf_slist[0]);
733 		if (copylen > klen)
734 			copylen = klen;
735 		if (copy_in_user(gf32->gf_slist, kgf->gf_slist, copylen))
736 			return -EFAULT;
737 	}
738 	return err;
739 }
740 EXPORT_SYMBOL(compat_mc_getsockopt);
741 
742 
743 /* Argument list sizes for compat_sys_socketcall */
744 #define AL(x) ((x) * sizeof(u32))
745 static unsigned char nas[21] = {
746 	AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
747 	AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
748 	AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
749 	AL(4), AL(5), AL(4)
750 };
751 #undef AL
752 
753 static inline long __compat_sys_sendmsg(int fd,
754 					struct compat_msghdr __user *msg,
755 					unsigned int flags)
756 {
757 	return __sys_sendmsg(fd, (struct user_msghdr __user *)msg,
758 			     flags | MSG_CMSG_COMPAT, false);
759 }
760 
761 COMPAT_SYSCALL_DEFINE3(sendmsg, int, fd, struct compat_msghdr __user *, msg,
762 		       unsigned int, flags)
763 {
764 	return __compat_sys_sendmsg(fd, msg, flags);
765 }
766 
767 static inline long __compat_sys_sendmmsg(int fd,
768 					 struct compat_mmsghdr __user *mmsg,
769 					 unsigned int vlen, unsigned int flags)
770 {
771 	return __sys_sendmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
772 			      flags | MSG_CMSG_COMPAT, false);
773 }
774 
775 COMPAT_SYSCALL_DEFINE4(sendmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
776 		       unsigned int, vlen, unsigned int, flags)
777 {
778 	return __compat_sys_sendmmsg(fd, mmsg, vlen, flags);
779 }
780 
781 static inline long __compat_sys_recvmsg(int fd,
782 					struct compat_msghdr __user *msg,
783 					unsigned int flags)
784 {
785 	return __sys_recvmsg(fd, (struct user_msghdr __user *)msg,
786 			     flags | MSG_CMSG_COMPAT, false);
787 }
788 
789 COMPAT_SYSCALL_DEFINE3(recvmsg, int, fd, struct compat_msghdr __user *, msg,
790 		       unsigned int, flags)
791 {
792 	return __compat_sys_recvmsg(fd, msg, flags);
793 }
794 
795 static inline long __compat_sys_recvfrom(int fd, void __user *buf,
796 					 compat_size_t len, unsigned int flags,
797 					 struct sockaddr __user *addr,
798 					 int __user *addrlen)
799 {
800 	return __sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr,
801 			      addrlen);
802 }
803 
804 COMPAT_SYSCALL_DEFINE4(recv, int, fd, void __user *, buf, compat_size_t, len, unsigned int, flags)
805 {
806 	return __compat_sys_recvfrom(fd, buf, len, flags, NULL, NULL);
807 }
808 
809 COMPAT_SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, buf, compat_size_t, len,
810 		       unsigned int, flags, struct sockaddr __user *, addr,
811 		       int __user *, addrlen)
812 {
813 	return __compat_sys_recvfrom(fd, buf, len, flags, addr, addrlen);
814 }
815 
816 COMPAT_SYSCALL_DEFINE5(recvmmsg_time64, int, fd, struct compat_mmsghdr __user *, mmsg,
817 		       unsigned int, vlen, unsigned int, flags,
818 		       struct __kernel_timespec __user *, timeout)
819 {
820 	return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
821 			      flags | MSG_CMSG_COMPAT, timeout, NULL);
822 }
823 
824 #ifdef CONFIG_COMPAT_32BIT_TIME
825 COMPAT_SYSCALL_DEFINE5(recvmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
826 		       unsigned int, vlen, unsigned int, flags,
827 		       struct old_timespec32 __user *, timeout)
828 {
829 	return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
830 			      flags | MSG_CMSG_COMPAT, NULL, timeout);
831 }
832 #endif
833 
834 COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args)
835 {
836 	u32 a[AUDITSC_ARGS];
837 	unsigned int len;
838 	u32 a0, a1;
839 	int ret;
840 
841 	if (call < SYS_SOCKET || call > SYS_SENDMMSG)
842 		return -EINVAL;
843 	len = nas[call];
844 	if (len > sizeof(a))
845 		return -EINVAL;
846 
847 	if (copy_from_user(a, args, len))
848 		return -EFAULT;
849 
850 	ret = audit_socketcall_compat(len / sizeof(a[0]), a);
851 	if (ret)
852 		return ret;
853 
854 	a0 = a[0];
855 	a1 = a[1];
856 
857 	switch (call) {
858 	case SYS_SOCKET:
859 		ret = __sys_socket(a0, a1, a[2]);
860 		break;
861 	case SYS_BIND:
862 		ret = __sys_bind(a0, compat_ptr(a1), a[2]);
863 		break;
864 	case SYS_CONNECT:
865 		ret = __sys_connect(a0, compat_ptr(a1), a[2]);
866 		break;
867 	case SYS_LISTEN:
868 		ret = __sys_listen(a0, a1);
869 		break;
870 	case SYS_ACCEPT:
871 		ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0);
872 		break;
873 	case SYS_GETSOCKNAME:
874 		ret = __sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]));
875 		break;
876 	case SYS_GETPEERNAME:
877 		ret = __sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2]));
878 		break;
879 	case SYS_SOCKETPAIR:
880 		ret = __sys_socketpair(a0, a1, a[2], compat_ptr(a[3]));
881 		break;
882 	case SYS_SEND:
883 		ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3], NULL, 0);
884 		break;
885 	case SYS_SENDTO:
886 		ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3],
887 				   compat_ptr(a[4]), a[5]);
888 		break;
889 	case SYS_RECV:
890 		ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
891 					    NULL, NULL);
892 		break;
893 	case SYS_RECVFROM:
894 		ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
895 					    compat_ptr(a[4]),
896 					    compat_ptr(a[5]));
897 		break;
898 	case SYS_SHUTDOWN:
899 		ret = __sys_shutdown(a0, a1);
900 		break;
901 	case SYS_SETSOCKOPT:
902 		ret = __compat_sys_setsockopt(a0, a1, a[2],
903 					      compat_ptr(a[3]), a[4]);
904 		break;
905 	case SYS_GETSOCKOPT:
906 		ret = __compat_sys_getsockopt(a0, a1, a[2],
907 					      compat_ptr(a[3]),
908 					      compat_ptr(a[4]));
909 		break;
910 	case SYS_SENDMSG:
911 		ret = __compat_sys_sendmsg(a0, compat_ptr(a1), a[2]);
912 		break;
913 	case SYS_SENDMMSG:
914 		ret = __compat_sys_sendmmsg(a0, compat_ptr(a1), a[2], a[3]);
915 		break;
916 	case SYS_RECVMSG:
917 		ret = __compat_sys_recvmsg(a0, compat_ptr(a1), a[2]);
918 		break;
919 	case SYS_RECVMMSG:
920 		ret = __sys_recvmmsg(a0, compat_ptr(a1), a[2],
921 				     a[3] | MSG_CMSG_COMPAT, NULL,
922 				     compat_ptr(a[4]));
923 		break;
924 	case SYS_ACCEPT4:
925 		ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]);
926 		break;
927 	default:
928 		ret = -EINVAL;
929 		break;
930 	}
931 	return ret;
932 }
933