xref: /linux/net/compat.c (revision 05ee19c18c2bb3dea69e29219017367c4a77e65a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * 32bit Socket syscall emulation. Based on arch/sparc64/kernel/sys_sparc32.c.
4  *
5  * Copyright (C) 2000		VA Linux Co
6  * Copyright (C) 2000		Don Dugger <n0ano@valinux.com>
7  * Copyright (C) 1999 		Arun Sharma <arun.sharma@intel.com>
8  * Copyright (C) 1997,1998 	Jakub Jelinek (jj@sunsite.mff.cuni.cz)
9  * Copyright (C) 1997 		David S. Miller (davem@caip.rutgers.edu)
10  * Copyright (C) 2000		Hewlett-Packard Co.
11  * Copyright (C) 2000		David Mosberger-Tang <davidm@hpl.hp.com>
12  * Copyright (C) 2000,2001	Andi Kleen, SuSE Labs
13  */
14 
15 #include <linux/kernel.h>
16 #include <linux/gfp.h>
17 #include <linux/fs.h>
18 #include <linux/types.h>
19 #include <linux/file.h>
20 #include <linux/icmpv6.h>
21 #include <linux/socket.h>
22 #include <linux/syscalls.h>
23 #include <linux/filter.h>
24 #include <linux/compat.h>
25 #include <linux/security.h>
26 #include <linux/audit.h>
27 #include <linux/export.h>
28 
29 #include <net/scm.h>
30 #include <net/sock.h>
31 #include <net/ip.h>
32 #include <net/ipv6.h>
33 #include <linux/uaccess.h>
34 #include <net/compat.h>
35 
36 int __get_compat_msghdr(struct msghdr *kmsg,
37 			struct compat_msghdr __user *umsg,
38 			struct sockaddr __user **save_addr,
39 			compat_uptr_t *ptr, compat_size_t *len)
40 {
41 	struct compat_msghdr msg;
42 	ssize_t err;
43 
44 	if (copy_from_user(&msg, umsg, sizeof(*umsg)))
45 		return -EFAULT;
46 
47 	kmsg->msg_flags = msg.msg_flags;
48 	kmsg->msg_namelen = msg.msg_namelen;
49 
50 	if (!msg.msg_name)
51 		kmsg->msg_namelen = 0;
52 
53 	if (kmsg->msg_namelen < 0)
54 		return -EINVAL;
55 
56 	if (kmsg->msg_namelen > sizeof(struct sockaddr_storage))
57 		kmsg->msg_namelen = sizeof(struct sockaddr_storage);
58 
59 	kmsg->msg_control_is_user = true;
60 	kmsg->msg_control_user = compat_ptr(msg.msg_control);
61 	kmsg->msg_controllen = msg.msg_controllen;
62 
63 	if (save_addr)
64 		*save_addr = compat_ptr(msg.msg_name);
65 
66 	if (msg.msg_name && kmsg->msg_namelen) {
67 		if (!save_addr) {
68 			err = move_addr_to_kernel(compat_ptr(msg.msg_name),
69 						  kmsg->msg_namelen,
70 						  kmsg->msg_name);
71 			if (err < 0)
72 				return err;
73 		}
74 	} else {
75 		kmsg->msg_name = NULL;
76 		kmsg->msg_namelen = 0;
77 	}
78 
79 	if (msg.msg_iovlen > UIO_MAXIOV)
80 		return -EMSGSIZE;
81 
82 	kmsg->msg_iocb = NULL;
83 	*ptr = msg.msg_iov;
84 	*len = msg.msg_iovlen;
85 	return 0;
86 }
87 
88 int get_compat_msghdr(struct msghdr *kmsg,
89 		      struct compat_msghdr __user *umsg,
90 		      struct sockaddr __user **save_addr,
91 		      struct iovec **iov)
92 {
93 	compat_uptr_t ptr;
94 	compat_size_t len;
95 	ssize_t err;
96 
97 	err = __get_compat_msghdr(kmsg, umsg, save_addr, &ptr, &len);
98 	if (err)
99 		return err;
100 
101 	err = compat_import_iovec(save_addr ? READ : WRITE, compat_ptr(ptr),
102 				   len, UIO_FASTIOV, iov, &kmsg->msg_iter);
103 	return err < 0 ? err : 0;
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) + sizeof(struct compat_cmsghdr)))
111 #define CMSG_COMPAT_SPACE(len)				\
112 	(sizeof(struct compat_cmsghdr) + CMSG_COMPAT_ALIGN(len))
113 #define CMSG_COMPAT_LEN(len)				\
114 	(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 __user *)(ucmsg) - (char __user *)(mhdr)->msg_control_user)))
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 	BUILD_BUG_ON(sizeof(struct compat_cmsghdr) !=
151 		     CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)));
152 
153 	kcmlen = 0;
154 	kcmsg_base = kcmsg = (struct cmsghdr *)stackbuf;
155 	ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
156 	while (ucmsg != NULL) {
157 		if (get_user(ucmlen, &ucmsg->cmsg_len))
158 			return -EFAULT;
159 
160 		/* Catch bogons. */
161 		if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
162 			return -EINVAL;
163 
164 		tmp = ((ucmlen - sizeof(*ucmsg)) + sizeof(struct cmsghdr));
165 		tmp = CMSG_ALIGN(tmp);
166 		kcmlen += tmp;
167 		ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
168 	}
169 	if (kcmlen == 0)
170 		return -EINVAL;
171 
172 	/* The kcmlen holds the 64-bit version of the control length.
173 	 * It may not be modified as we do not stick it into the kmsg
174 	 * until we have successfully copied over all of the data
175 	 * from the user.
176 	 */
177 	if (kcmlen > stackbuf_size)
178 		kcmsg_base = kcmsg = sock_kmalloc(sk, kcmlen, GFP_KERNEL);
179 	if (kcmsg == NULL)
180 		return -ENOBUFS;
181 
182 	/* Now copy them over neatly. */
183 	memset(kcmsg, 0, kcmlen);
184 	ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
185 	while (ucmsg != NULL) {
186 		if (__get_user(ucmlen, &ucmsg->cmsg_len))
187 			goto Efault;
188 		if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
189 			goto Einval;
190 		tmp = ((ucmlen - sizeof(*ucmsg)) + sizeof(struct cmsghdr));
191 		if ((char *)kcmsg_base + kcmlen - (char *)kcmsg < CMSG_ALIGN(tmp))
192 			goto Einval;
193 		kcmsg->cmsg_len = tmp;
194 		tmp = CMSG_ALIGN(tmp);
195 		if (__get_user(kcmsg->cmsg_level, &ucmsg->cmsg_level) ||
196 		    __get_user(kcmsg->cmsg_type, &ucmsg->cmsg_type) ||
197 		    copy_from_user(CMSG_DATA(kcmsg),
198 				   CMSG_COMPAT_DATA(ucmsg),
199 				   (ucmlen - sizeof(*ucmsg))))
200 			goto Efault;
201 
202 		/* Advance. */
203 		kcmsg = (struct cmsghdr *)((char *)kcmsg + tmp);
204 		ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
205 	}
206 
207 	/*
208 	 * check the length of messages copied in is the same as the
209 	 * what we get from the first loop
210 	 */
211 	if ((char *)kcmsg - (char *)kcmsg_base != kcmlen)
212 		goto Einval;
213 
214 	/* Ok, looks like we made it.  Hook it up and return success. */
215 	kmsg->msg_control = kcmsg_base;
216 	kmsg->msg_controllen = kcmlen;
217 	return 0;
218 
219 Einval:
220 	err = -EINVAL;
221 Efault:
222 	if (kcmsg_base != (struct cmsghdr *)stackbuf)
223 		sock_kfree_s(sk, kcmsg_base, kcmlen);
224 	return err;
225 }
226 
227 int put_cmsg_compat(struct msghdr *kmsg, int level, int type, int len, void *data)
228 {
229 	struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
230 	struct compat_cmsghdr cmhdr;
231 	struct old_timeval32 ctv;
232 	struct old_timespec32 cts[3];
233 	int cmlen;
234 
235 	if (cm == NULL || kmsg->msg_controllen < sizeof(*cm)) {
236 		kmsg->msg_flags |= MSG_CTRUNC;
237 		return 0; /* XXX: return error? check spec. */
238 	}
239 
240 	if (!COMPAT_USE_64BIT_TIME) {
241 		if (level == SOL_SOCKET && type == SO_TIMESTAMP_OLD) {
242 			struct __kernel_old_timeval *tv = (struct __kernel_old_timeval *)data;
243 			ctv.tv_sec = tv->tv_sec;
244 			ctv.tv_usec = tv->tv_usec;
245 			data = &ctv;
246 			len = sizeof(ctv);
247 		}
248 		if (level == SOL_SOCKET &&
249 		    (type == SO_TIMESTAMPNS_OLD || type == SO_TIMESTAMPING_OLD)) {
250 			int count = type == SO_TIMESTAMPNS_OLD ? 1 : 3;
251 			int i;
252 			struct __kernel_old_timespec *ts = data;
253 			for (i = 0; i < count; i++) {
254 				cts[i].tv_sec = ts[i].tv_sec;
255 				cts[i].tv_nsec = ts[i].tv_nsec;
256 			}
257 			data = &cts;
258 			len = sizeof(cts[0]) * count;
259 		}
260 	}
261 
262 	cmlen = CMSG_COMPAT_LEN(len);
263 	if (kmsg->msg_controllen < cmlen) {
264 		kmsg->msg_flags |= MSG_CTRUNC;
265 		cmlen = kmsg->msg_controllen;
266 	}
267 	cmhdr.cmsg_level = level;
268 	cmhdr.cmsg_type = type;
269 	cmhdr.cmsg_len = cmlen;
270 
271 	if (copy_to_user(cm, &cmhdr, sizeof cmhdr))
272 		return -EFAULT;
273 	if (copy_to_user(CMSG_COMPAT_DATA(cm), data, cmlen - sizeof(struct compat_cmsghdr)))
274 		return -EFAULT;
275 	cmlen = CMSG_COMPAT_SPACE(len);
276 	if (kmsg->msg_controllen < cmlen)
277 		cmlen = kmsg->msg_controllen;
278 	kmsg->msg_control += cmlen;
279 	kmsg->msg_controllen -= cmlen;
280 	return 0;
281 }
282 
283 void scm_detach_fds_compat(struct msghdr *kmsg, struct scm_cookie *scm)
284 {
285 	struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
286 	int fdmax = (kmsg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int);
287 	int fdnum = scm->fp->count;
288 	struct file **fp = scm->fp->fp;
289 	int __user *cmfptr;
290 	int err = 0, i;
291 
292 	if (fdnum < fdmax)
293 		fdmax = fdnum;
294 
295 	for (i = 0, cmfptr = (int __user *) CMSG_COMPAT_DATA(cm); i < fdmax; i++, cmfptr++) {
296 		int new_fd;
297 		err = security_file_receive(fp[i]);
298 		if (err)
299 			break;
300 		err = get_unused_fd_flags(MSG_CMSG_CLOEXEC & kmsg->msg_flags
301 					  ? O_CLOEXEC : 0);
302 		if (err < 0)
303 			break;
304 		new_fd = err;
305 		err = put_user(new_fd, cmfptr);
306 		if (err) {
307 			put_unused_fd(new_fd);
308 			break;
309 		}
310 		/* Bump the usage count and install the file. */
311 		fd_install(new_fd, get_file(fp[i]));
312 	}
313 
314 	if (i > 0) {
315 		int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
316 		err = put_user(SOL_SOCKET, &cm->cmsg_level);
317 		if (!err)
318 			err = put_user(SCM_RIGHTS, &cm->cmsg_type);
319 		if (!err)
320 			err = put_user(cmlen, &cm->cmsg_len);
321 		if (!err) {
322 			cmlen = CMSG_COMPAT_SPACE(i * sizeof(int));
323 			kmsg->msg_control += cmlen;
324 			kmsg->msg_controllen -= cmlen;
325 		}
326 	}
327 	if (i < fdnum)
328 		kmsg->msg_flags |= MSG_CTRUNC;
329 
330 	/*
331 	 * All of the files that fit in the message have had their
332 	 * usage counts incremented, so we just free the list.
333 	 */
334 	__scm_destroy(scm);
335 }
336 
337 /* allocate a 64-bit sock_fprog on the user stack for duration of syscall. */
338 struct sock_fprog __user *get_compat_bpf_fprog(char __user *optval)
339 {
340 	struct compat_sock_fprog __user *fprog32 = (struct compat_sock_fprog __user *)optval;
341 	struct sock_fprog __user *kfprog = compat_alloc_user_space(sizeof(struct sock_fprog));
342 	struct compat_sock_fprog f32;
343 	struct sock_fprog f;
344 
345 	if (copy_from_user(&f32, fprog32, sizeof(*fprog32)))
346 		return NULL;
347 	memset(&f, 0, sizeof(f));
348 	f.len = f32.len;
349 	f.filter = compat_ptr(f32.filter);
350 	if (copy_to_user(kfprog, &f, sizeof(struct sock_fprog)))
351 		return NULL;
352 
353 	return kfprog;
354 }
355 EXPORT_SYMBOL_GPL(get_compat_bpf_fprog);
356 
357 static int do_set_attach_filter(struct socket *sock, int level, int optname,
358 				char __user *optval, unsigned int optlen)
359 {
360 	struct sock_fprog __user *kfprog;
361 
362 	kfprog = get_compat_bpf_fprog(optval);
363 	if (!kfprog)
364 		return -EFAULT;
365 
366 	return sock_setsockopt(sock, level, optname, (char __user *)kfprog,
367 			      sizeof(struct sock_fprog));
368 }
369 
370 static int compat_sock_setsockopt(struct socket *sock, int level, int optname,
371 				char __user *optval, unsigned int optlen)
372 {
373 	if (optname == SO_ATTACH_FILTER ||
374 	    optname == SO_ATTACH_REUSEPORT_CBPF)
375 		return do_set_attach_filter(sock, level, optname,
376 					    optval, optlen);
377 	return sock_setsockopt(sock, level, optname, optval, optlen);
378 }
379 
380 static int __compat_sys_setsockopt(int fd, int level, int optname,
381 				   char __user *optval, unsigned int optlen)
382 {
383 	int err;
384 	struct socket *sock;
385 
386 	if (optlen > INT_MAX)
387 		return -EINVAL;
388 
389 	sock = sockfd_lookup(fd, &err);
390 	if (sock) {
391 		err = security_socket_setsockopt(sock, level, optname);
392 		if (err) {
393 			sockfd_put(sock);
394 			return err;
395 		}
396 
397 		if (level == SOL_SOCKET)
398 			err = compat_sock_setsockopt(sock, level,
399 					optname, optval, optlen);
400 		else if (sock->ops->compat_setsockopt)
401 			err = sock->ops->compat_setsockopt(sock, level,
402 					optname, optval, optlen);
403 		else
404 			err = sock->ops->setsockopt(sock, level,
405 					optname, optval, optlen);
406 		sockfd_put(sock);
407 	}
408 	return err;
409 }
410 
411 COMPAT_SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
412 		       char __user *, optval, unsigned int, optlen)
413 {
414 	return __compat_sys_setsockopt(fd, level, optname, optval, optlen);
415 }
416 
417 static int __compat_sys_getsockopt(int fd, int level, int optname,
418 				   char __user *optval,
419 				   int __user *optlen)
420 {
421 	int err;
422 	struct socket *sock = sockfd_lookup(fd, &err);
423 
424 	if (sock) {
425 		err = security_socket_getsockopt(sock, level, optname);
426 		if (err) {
427 			sockfd_put(sock);
428 			return err;
429 		}
430 
431 		if (level == SOL_SOCKET)
432 			err = sock_getsockopt(sock, level,
433 					optname, optval, optlen);
434 		else if (sock->ops->compat_getsockopt)
435 			err = sock->ops->compat_getsockopt(sock, level,
436 					optname, optval, optlen);
437 		else
438 			err = sock->ops->getsockopt(sock, level,
439 					optname, optval, optlen);
440 		sockfd_put(sock);
441 	}
442 	return err;
443 }
444 
445 COMPAT_SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname,
446 		       char __user *, optval, int __user *, optlen)
447 {
448 	return __compat_sys_getsockopt(fd, level, optname, optval, optlen);
449 }
450 
451 struct compat_group_req {
452 	__u32				 gr_interface;
453 	struct __kernel_sockaddr_storage gr_group
454 		__aligned(4);
455 } __packed;
456 
457 struct compat_group_source_req {
458 	__u32				 gsr_interface;
459 	struct __kernel_sockaddr_storage gsr_group
460 		__aligned(4);
461 	struct __kernel_sockaddr_storage gsr_source
462 		__aligned(4);
463 } __packed;
464 
465 struct compat_group_filter {
466 	__u32				 gf_interface;
467 	struct __kernel_sockaddr_storage gf_group
468 		__aligned(4);
469 	__u32				 gf_fmode;
470 	__u32				 gf_numsrc;
471 	struct __kernel_sockaddr_storage gf_slist[1]
472 		__aligned(4);
473 } __packed;
474 
475 #define __COMPAT_GF0_SIZE (sizeof(struct compat_group_filter) - \
476 			sizeof(struct __kernel_sockaddr_storage))
477 
478 
479 int compat_mc_setsockopt(struct sock *sock, int level, int optname,
480 	char __user *optval, unsigned int optlen,
481 	int (*setsockopt)(struct sock *, int, int, char __user *, unsigned int))
482 {
483 	char __user	*koptval = optval;
484 	int		koptlen = optlen;
485 
486 	switch (optname) {
487 	case MCAST_JOIN_GROUP:
488 	case MCAST_LEAVE_GROUP:
489 	{
490 		struct compat_group_req __user *gr32 = (void __user *)optval;
491 		struct group_req __user *kgr =
492 			compat_alloc_user_space(sizeof(struct group_req));
493 		u32 interface;
494 
495 		if (!access_ok(gr32, sizeof(*gr32)) ||
496 		    !access_ok(kgr, sizeof(struct group_req)) ||
497 		    __get_user(interface, &gr32->gr_interface) ||
498 		    __put_user(interface, &kgr->gr_interface) ||
499 		    copy_in_user(&kgr->gr_group, &gr32->gr_group,
500 				sizeof(kgr->gr_group)))
501 			return -EFAULT;
502 		koptval = (char __user *)kgr;
503 		koptlen = sizeof(struct group_req);
504 		break;
505 	}
506 	case MCAST_JOIN_SOURCE_GROUP:
507 	case MCAST_LEAVE_SOURCE_GROUP:
508 	case MCAST_BLOCK_SOURCE:
509 	case MCAST_UNBLOCK_SOURCE:
510 	{
511 		struct compat_group_source_req __user *gsr32 = (void __user *)optval;
512 		struct group_source_req __user *kgsr = compat_alloc_user_space(
513 			sizeof(struct group_source_req));
514 		u32 interface;
515 
516 		if (!access_ok(gsr32, sizeof(*gsr32)) ||
517 		    !access_ok(kgsr,
518 			sizeof(struct group_source_req)) ||
519 		    __get_user(interface, &gsr32->gsr_interface) ||
520 		    __put_user(interface, &kgsr->gsr_interface) ||
521 		    copy_in_user(&kgsr->gsr_group, &gsr32->gsr_group,
522 				sizeof(kgsr->gsr_group)) ||
523 		    copy_in_user(&kgsr->gsr_source, &gsr32->gsr_source,
524 				sizeof(kgsr->gsr_source)))
525 			return -EFAULT;
526 		koptval = (char __user *)kgsr;
527 		koptlen = sizeof(struct group_source_req);
528 		break;
529 	}
530 	case MCAST_MSFILTER:
531 	{
532 		struct compat_group_filter __user *gf32 = (void __user *)optval;
533 		struct group_filter __user *kgf;
534 		u32 interface, fmode, numsrc;
535 
536 		if (!access_ok(gf32, __COMPAT_GF0_SIZE) ||
537 		    __get_user(interface, &gf32->gf_interface) ||
538 		    __get_user(fmode, &gf32->gf_fmode) ||
539 		    __get_user(numsrc, &gf32->gf_numsrc))
540 			return -EFAULT;
541 		koptlen = optlen + sizeof(struct group_filter) -
542 				sizeof(struct compat_group_filter);
543 		if (koptlen < GROUP_FILTER_SIZE(numsrc))
544 			return -EINVAL;
545 		kgf = compat_alloc_user_space(koptlen);
546 		if (!access_ok(kgf, koptlen) ||
547 		    __put_user(interface, &kgf->gf_interface) ||
548 		    __put_user(fmode, &kgf->gf_fmode) ||
549 		    __put_user(numsrc, &kgf->gf_numsrc) ||
550 		    copy_in_user(&kgf->gf_group, &gf32->gf_group,
551 				sizeof(kgf->gf_group)) ||
552 		    (numsrc && copy_in_user(kgf->gf_slist, gf32->gf_slist,
553 				numsrc * sizeof(kgf->gf_slist[0]))))
554 			return -EFAULT;
555 		koptval = (char __user *)kgf;
556 		break;
557 	}
558 
559 	default:
560 		break;
561 	}
562 	return setsockopt(sock, level, optname, koptval, koptlen);
563 }
564 EXPORT_SYMBOL(compat_mc_setsockopt);
565 
566 int compat_mc_getsockopt(struct sock *sock, int level, int optname,
567 	char __user *optval, int __user *optlen,
568 	int (*getsockopt)(struct sock *, int, int, char __user *, int __user *))
569 {
570 	struct compat_group_filter __user *gf32 = (void __user *)optval;
571 	struct group_filter __user *kgf;
572 	int __user	*koptlen;
573 	u32 interface, fmode, numsrc;
574 	int klen, ulen, err;
575 
576 	if (optname != MCAST_MSFILTER)
577 		return getsockopt(sock, level, optname, optval, optlen);
578 
579 	koptlen = compat_alloc_user_space(sizeof(*koptlen));
580 	if (!access_ok(optlen, sizeof(*optlen)) ||
581 	    __get_user(ulen, optlen))
582 		return -EFAULT;
583 
584 	/* adjust len for pad */
585 	klen = ulen + sizeof(*kgf) - sizeof(*gf32);
586 
587 	if (klen < GROUP_FILTER_SIZE(0))
588 		return -EINVAL;
589 
590 	if (!access_ok(koptlen, sizeof(*koptlen)) ||
591 	    __put_user(klen, koptlen))
592 		return -EFAULT;
593 
594 	/* have to allow space for previous compat_alloc_user_space, too */
595 	kgf = compat_alloc_user_space(klen+sizeof(*optlen));
596 
597 	if (!access_ok(gf32, __COMPAT_GF0_SIZE) ||
598 	    __get_user(interface, &gf32->gf_interface) ||
599 	    __get_user(fmode, &gf32->gf_fmode) ||
600 	    __get_user(numsrc, &gf32->gf_numsrc) ||
601 	    __put_user(interface, &kgf->gf_interface) ||
602 	    __put_user(fmode, &kgf->gf_fmode) ||
603 	    __put_user(numsrc, &kgf->gf_numsrc) ||
604 	    copy_in_user(&kgf->gf_group, &gf32->gf_group, sizeof(kgf->gf_group)))
605 		return -EFAULT;
606 
607 	err = getsockopt(sock, level, optname, (char __user *)kgf, koptlen);
608 	if (err)
609 		return err;
610 
611 	if (!access_ok(koptlen, sizeof(*koptlen)) ||
612 	    __get_user(klen, koptlen))
613 		return -EFAULT;
614 
615 	ulen = klen - (sizeof(*kgf)-sizeof(*gf32));
616 
617 	if (!access_ok(optlen, sizeof(*optlen)) ||
618 	    __put_user(ulen, optlen))
619 		return -EFAULT;
620 
621 	if (!access_ok(kgf, klen) ||
622 	    !access_ok(gf32, ulen) ||
623 	    __get_user(interface, &kgf->gf_interface) ||
624 	    __get_user(fmode, &kgf->gf_fmode) ||
625 	    __get_user(numsrc, &kgf->gf_numsrc) ||
626 	    __put_user(interface, &gf32->gf_interface) ||
627 	    __put_user(fmode, &gf32->gf_fmode) ||
628 	    __put_user(numsrc, &gf32->gf_numsrc))
629 		return -EFAULT;
630 	if (numsrc) {
631 		int copylen;
632 
633 		klen -= GROUP_FILTER_SIZE(0);
634 		copylen = numsrc * sizeof(gf32->gf_slist[0]);
635 		if (copylen > klen)
636 			copylen = klen;
637 		if (copy_in_user(gf32->gf_slist, kgf->gf_slist, copylen))
638 			return -EFAULT;
639 	}
640 	return err;
641 }
642 EXPORT_SYMBOL(compat_mc_getsockopt);
643 
644 
645 /* Argument list sizes for compat_sys_socketcall */
646 #define AL(x) ((x) * sizeof(u32))
647 static unsigned char nas[21] = {
648 	AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
649 	AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
650 	AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
651 	AL(4), AL(5), AL(4)
652 };
653 #undef AL
654 
655 static inline long __compat_sys_sendmsg(int fd,
656 					struct compat_msghdr __user *msg,
657 					unsigned int flags)
658 {
659 	return __sys_sendmsg(fd, (struct user_msghdr __user *)msg,
660 			     flags | MSG_CMSG_COMPAT, false);
661 }
662 
663 COMPAT_SYSCALL_DEFINE3(sendmsg, int, fd, struct compat_msghdr __user *, msg,
664 		       unsigned int, flags)
665 {
666 	return __compat_sys_sendmsg(fd, msg, flags);
667 }
668 
669 static inline long __compat_sys_sendmmsg(int fd,
670 					 struct compat_mmsghdr __user *mmsg,
671 					 unsigned int vlen, unsigned int flags)
672 {
673 	return __sys_sendmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
674 			      flags | MSG_CMSG_COMPAT, false);
675 }
676 
677 COMPAT_SYSCALL_DEFINE4(sendmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
678 		       unsigned int, vlen, unsigned int, flags)
679 {
680 	return __compat_sys_sendmmsg(fd, mmsg, vlen, flags);
681 }
682 
683 static inline long __compat_sys_recvmsg(int fd,
684 					struct compat_msghdr __user *msg,
685 					unsigned int flags)
686 {
687 	return __sys_recvmsg(fd, (struct user_msghdr __user *)msg,
688 			     flags | MSG_CMSG_COMPAT, false);
689 }
690 
691 COMPAT_SYSCALL_DEFINE3(recvmsg, int, fd, struct compat_msghdr __user *, msg,
692 		       unsigned int, flags)
693 {
694 	return __compat_sys_recvmsg(fd, msg, flags);
695 }
696 
697 static inline long __compat_sys_recvfrom(int fd, void __user *buf,
698 					 compat_size_t len, unsigned int flags,
699 					 struct sockaddr __user *addr,
700 					 int __user *addrlen)
701 {
702 	return __sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr,
703 			      addrlen);
704 }
705 
706 COMPAT_SYSCALL_DEFINE4(recv, int, fd, void __user *, buf, compat_size_t, len, unsigned int, flags)
707 {
708 	return __compat_sys_recvfrom(fd, buf, len, flags, NULL, NULL);
709 }
710 
711 COMPAT_SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, buf, compat_size_t, len,
712 		       unsigned int, flags, struct sockaddr __user *, addr,
713 		       int __user *, addrlen)
714 {
715 	return __compat_sys_recvfrom(fd, buf, len, flags, addr, addrlen);
716 }
717 
718 COMPAT_SYSCALL_DEFINE5(recvmmsg_time64, int, fd, struct compat_mmsghdr __user *, mmsg,
719 		       unsigned int, vlen, unsigned int, flags,
720 		       struct __kernel_timespec __user *, timeout)
721 {
722 	return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
723 			      flags | MSG_CMSG_COMPAT, timeout, NULL);
724 }
725 
726 #ifdef CONFIG_COMPAT_32BIT_TIME
727 COMPAT_SYSCALL_DEFINE5(recvmmsg_time32, int, fd, struct compat_mmsghdr __user *, mmsg,
728 		       unsigned int, vlen, unsigned int, flags,
729 		       struct old_timespec32 __user *, timeout)
730 {
731 	return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
732 			      flags | MSG_CMSG_COMPAT, NULL, timeout);
733 }
734 #endif
735 
736 COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args)
737 {
738 	u32 a[AUDITSC_ARGS];
739 	unsigned int len;
740 	u32 a0, a1;
741 	int ret;
742 
743 	if (call < SYS_SOCKET || call > SYS_SENDMMSG)
744 		return -EINVAL;
745 	len = nas[call];
746 	if (len > sizeof(a))
747 		return -EINVAL;
748 
749 	if (copy_from_user(a, args, len))
750 		return -EFAULT;
751 
752 	ret = audit_socketcall_compat(len / sizeof(a[0]), a);
753 	if (ret)
754 		return ret;
755 
756 	a0 = a[0];
757 	a1 = a[1];
758 
759 	switch (call) {
760 	case SYS_SOCKET:
761 		ret = __sys_socket(a0, a1, a[2]);
762 		break;
763 	case SYS_BIND:
764 		ret = __sys_bind(a0, compat_ptr(a1), a[2]);
765 		break;
766 	case SYS_CONNECT:
767 		ret = __sys_connect(a0, compat_ptr(a1), a[2]);
768 		break;
769 	case SYS_LISTEN:
770 		ret = __sys_listen(a0, a1);
771 		break;
772 	case SYS_ACCEPT:
773 		ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0);
774 		break;
775 	case SYS_GETSOCKNAME:
776 		ret = __sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]));
777 		break;
778 	case SYS_GETPEERNAME:
779 		ret = __sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2]));
780 		break;
781 	case SYS_SOCKETPAIR:
782 		ret = __sys_socketpair(a0, a1, a[2], compat_ptr(a[3]));
783 		break;
784 	case SYS_SEND:
785 		ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3], NULL, 0);
786 		break;
787 	case SYS_SENDTO:
788 		ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3],
789 				   compat_ptr(a[4]), a[5]);
790 		break;
791 	case SYS_RECV:
792 		ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
793 					    NULL, NULL);
794 		break;
795 	case SYS_RECVFROM:
796 		ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
797 					    compat_ptr(a[4]),
798 					    compat_ptr(a[5]));
799 		break;
800 	case SYS_SHUTDOWN:
801 		ret = __sys_shutdown(a0, a1);
802 		break;
803 	case SYS_SETSOCKOPT:
804 		ret = __compat_sys_setsockopt(a0, a1, a[2],
805 					      compat_ptr(a[3]), a[4]);
806 		break;
807 	case SYS_GETSOCKOPT:
808 		ret = __compat_sys_getsockopt(a0, a1, a[2],
809 					      compat_ptr(a[3]),
810 					      compat_ptr(a[4]));
811 		break;
812 	case SYS_SENDMSG:
813 		ret = __compat_sys_sendmsg(a0, compat_ptr(a1), a[2]);
814 		break;
815 	case SYS_SENDMMSG:
816 		ret = __compat_sys_sendmmsg(a0, compat_ptr(a1), a[2], a[3]);
817 		break;
818 	case SYS_RECVMSG:
819 		ret = __compat_sys_recvmsg(a0, compat_ptr(a1), a[2]);
820 		break;
821 	case SYS_RECVMMSG:
822 		ret = __sys_recvmmsg(a0, compat_ptr(a1), a[2],
823 				     a[3] | MSG_CMSG_COMPAT, NULL,
824 				     compat_ptr(a[4]));
825 		break;
826 	case SYS_ACCEPT4:
827 		ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]);
828 		break;
829 	default:
830 		ret = -EINVAL;
831 		break;
832 	}
833 	return ret;
834 }
835