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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 <[email protected]>
7 * Copyright (C) 1999 Arun Sharma <[email protected]>
8 * Copyright (C) 1997,1998 Jakub Jelinek ([email protected])
9 * Copyright (C) 1997 David S. Miller ([email protected])
10 * Copyright (C) 2000 Hewlett-Packard Co.
11 * Copyright (C) 2000 David Mosberger-Tang <[email protected]>
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
36int __get_compat_msghdr(struct msghdr *kmsg,
37 struct compat_msghdr *msg,
38 struct sockaddr __user **save_addr)
39{
40 ssize_t err;
41
42 kmsg->msg_flags = msg->msg_flags;
43 kmsg->msg_namelen = msg->msg_namelen;
44
45 if (!msg->msg_name)
46 kmsg->msg_namelen = 0;
47
48 if (kmsg->msg_namelen < 0)
49 return -EINVAL;
50
51 if (kmsg->msg_namelen > sizeof(struct sockaddr_storage))
52 kmsg->msg_namelen = sizeof(struct sockaddr_storage);
53
54 kmsg->msg_control_is_user = true;
55 kmsg->msg_get_inq = 0;
56 kmsg->msg_control_user = compat_ptr(msg->msg_control);
57 kmsg->msg_controllen = msg->msg_controllen;
58
59 if (save_addr)
60 *save_addr = compat_ptr(msg->msg_name);
61
62 if (msg->msg_name && kmsg->msg_namelen) {
63 if (!save_addr) {
64 err = move_addr_to_kernel(compat_ptr(msg->msg_name),
65 kmsg->msg_namelen,
66 kmsg->msg_name);
67 if (err < 0)
68 return err;
69 }
70 } else {
71 kmsg->msg_name = NULL;
72 kmsg->msg_namelen = 0;
73 }
74
75 if (msg->msg_iovlen > UIO_MAXIOV)
76 return -EMSGSIZE;
77
78 kmsg->msg_ubuf = NULL;
79 return 0;
80}
81
82int get_compat_msghdr(struct msghdr *kmsg,
83 struct compat_msghdr __user *umsg,
84 struct sockaddr __user **save_addr,
85 struct iovec **iov)
86{
87 struct compat_msghdr msg;
88 ssize_t err;
89
90 if (copy_from_user(&msg, umsg, sizeof(*umsg)))
91 return -EFAULT;
92
93 err = __get_compat_msghdr(kmsg, &msg, save_addr);
94 if (err)
95 return err;
96
97 err = import_iovec(save_addr ? ITER_DEST : ITER_SOURCE,
98 compat_ptr(msg.msg_iov), msg.msg_iovlen,
99 UIO_FASTIOV, iov, &kmsg->msg_iter);
100 return err < 0 ? err : 0;
101}
102
103/* Bleech... */
104#define CMSG_COMPAT_ALIGN(len) ALIGN((len), sizeof(s32))
105
106#define CMSG_COMPAT_DATA(cmsg) \
107 ((void __user *)((char __user *)(cmsg) + sizeof(struct compat_cmsghdr)))
108#define CMSG_COMPAT_SPACE(len) \
109 (sizeof(struct compat_cmsghdr) + CMSG_COMPAT_ALIGN(len))
110#define CMSG_COMPAT_LEN(len) \
111 (sizeof(struct compat_cmsghdr) + (len))
112
113#define CMSG_COMPAT_FIRSTHDR(msg) \
114 (((msg)->msg_controllen) >= sizeof(struct compat_cmsghdr) ? \
115 (struct compat_cmsghdr __user *)((msg)->msg_control_user) : \
116 (struct compat_cmsghdr __user *)NULL)
117
118#define CMSG_COMPAT_OK(ucmlen, ucmsg, mhdr) \
119 ((ucmlen) >= sizeof(struct compat_cmsghdr) && \
120 (ucmlen) <= (unsigned long) \
121 ((mhdr)->msg_controllen - \
122 ((char __user *)(ucmsg) - (char __user *)(mhdr)->msg_control_user)))
123
124static inline struct compat_cmsghdr __user *cmsg_compat_nxthdr(struct msghdr *msg,
125 struct compat_cmsghdr __user *cmsg, int cmsg_len)
126{
127 char __user *ptr = (char __user *)cmsg + CMSG_COMPAT_ALIGN(cmsg_len);
128 if ((unsigned long)(ptr + 1 - (char __user *)msg->msg_control_user) >
129 msg->msg_controllen)
130 return NULL;
131 return (struct compat_cmsghdr __user *)ptr;
132}
133
134/* There is a lot of hair here because the alignment rules (and
135 * thus placement) of cmsg headers and length are different for
136 * 32-bit apps. -DaveM
137 */
138int cmsghdr_from_user_compat_to_kern(struct msghdr *kmsg, struct sock *sk,
139 unsigned char *stackbuf, int stackbuf_size)
140{
141 struct compat_cmsghdr __user *ucmsg;
142 struct cmsghdr *kcmsg, *kcmsg_base;
143 compat_size_t ucmlen;
144 __kernel_size_t kcmlen, tmp;
145 int err = -EFAULT;
146
147 BUILD_BUG_ON(sizeof(struct compat_cmsghdr) !=
148 CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)));
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 - sizeof(*ucmsg)) + sizeof(struct cmsghdr));
162 tmp = CMSG_ALIGN(tmp);
163 kcmlen += tmp;
164 ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
165 }
166 if (kcmlen == 0)
167 return -EINVAL;
168
169 /* The kcmlen holds the 64-bit version of the control length.
170 * It may not be modified as we do not stick it into the kmsg
171 * until we have successfully copied over all of the data
172 * from the user.
173 */
174 if (kcmlen > stackbuf_size)
175 kcmsg_base = kcmsg = sock_kmalloc(sk, kcmlen, GFP_KERNEL);
176 if (kcmsg == NULL)
177 return -ENOMEM;
178
179 /* Now copy them over neatly. */
180 memset(kcmsg, 0, kcmlen);
181 ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
182 while (ucmsg != NULL) {
183 struct compat_cmsghdr cmsg;
184 if (copy_from_user(&cmsg, ucmsg, sizeof(cmsg)))
185 goto Efault;
186 if (!CMSG_COMPAT_OK(cmsg.cmsg_len, ucmsg, kmsg))
187 goto Einval;
188 tmp = ((cmsg.cmsg_len - sizeof(*ucmsg)) + sizeof(struct cmsghdr));
189 if ((char *)kcmsg_base + kcmlen - (char *)kcmsg < CMSG_ALIGN(tmp))
190 goto Einval;
191 kcmsg->cmsg_len = tmp;
192 kcmsg->cmsg_level = cmsg.cmsg_level;
193 kcmsg->cmsg_type = cmsg.cmsg_type;
194 tmp = CMSG_ALIGN(tmp);
195 if (copy_from_user(CMSG_DATA(kcmsg),
196 CMSG_COMPAT_DATA(ucmsg),
197 (cmsg.cmsg_len - sizeof(*ucmsg))))
198 goto Efault;
199
200 /* Advance. */
201 kcmsg = (struct cmsghdr *)((char *)kcmsg + tmp);
202 ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, cmsg.cmsg_len);
203 }
204
205 /*
206 * check the length of messages copied in is the same as the
207 * what we get from the first loop
208 */
209 if ((char *)kcmsg - (char *)kcmsg_base != kcmlen)
210 goto Einval;
211
212 /* Ok, looks like we made it. Hook it up and return success. */
213 kmsg->msg_control_is_user = false;
214 kmsg->msg_control = kcmsg_base;
215 kmsg->msg_controllen = kcmlen;
216 return 0;
217
218Einval:
219 err = -EINVAL;
220Efault:
221 if (kcmsg_base != (struct cmsghdr *)stackbuf)
222 sock_kfree_s(sk, kcmsg_base, kcmlen);
223 return err;
224}
225
226int put_cmsg_compat(struct msghdr *kmsg, int level, int type, int len, void *data)
227{
228 struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control_user;
229 struct compat_cmsghdr cmhdr;
230 struct old_timeval32 ctv;
231 struct old_timespec32 cts[3];
232 int cmlen;
233
234 if (cm == NULL || kmsg->msg_controllen < sizeof(*cm)) {
235 kmsg->msg_flags |= MSG_CTRUNC;
236 return 0; /* XXX: return error? check spec. */
237 }
238
239 if (!COMPAT_USE_64BIT_TIME) {
240 if (level == SOL_SOCKET && type == SO_TIMESTAMP_OLD) {
241 struct __kernel_old_timeval *tv = (struct __kernel_old_timeval *)data;
242 ctv.tv_sec = tv->tv_sec;
243 ctv.tv_usec = tv->tv_usec;
244 data = &ctv;
245 len = sizeof(ctv);
246 }
247 if (level == SOL_SOCKET &&
248 (type == SO_TIMESTAMPNS_OLD || type == SO_TIMESTAMPING_OLD)) {
249 int count = type == SO_TIMESTAMPNS_OLD ? 1 : 3;
250 int i;
251 struct __kernel_old_timespec *ts = data;
252 for (i = 0; i < count; i++) {
253 cts[i].tv_sec = ts[i].tv_sec;
254 cts[i].tv_nsec = ts[i].tv_nsec;
255 }
256 data = &cts;
257 len = sizeof(cts[0]) * count;
258 }
259 }
260
261 cmlen = CMSG_COMPAT_LEN(len);
262 if (kmsg->msg_controllen < cmlen) {
263 kmsg->msg_flags |= MSG_CTRUNC;
264 cmlen = kmsg->msg_controllen;
265 }
266 cmhdr.cmsg_level = level;
267 cmhdr.cmsg_type = type;
268 cmhdr.cmsg_len = cmlen;
269
270 if (copy_to_user(cm, &cmhdr, sizeof cmhdr))
271 return -EFAULT;
272 if (copy_to_user(CMSG_COMPAT_DATA(cm), data, cmlen - sizeof(struct compat_cmsghdr)))
273 return -EFAULT;
274 cmlen = CMSG_COMPAT_SPACE(len);
275 if (kmsg->msg_controllen < cmlen)
276 cmlen = kmsg->msg_controllen;
277 kmsg->msg_control_user += cmlen;
278 kmsg->msg_controllen -= cmlen;
279 return 0;
280}
281
282static int scm_max_fds_compat(struct msghdr *msg)
283{
284 if (msg->msg_controllen <= sizeof(struct compat_cmsghdr))
285 return 0;
286 return (msg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int);
287}
288
289void scm_detach_fds_compat(struct msghdr *msg, struct scm_cookie *scm, bool notrunc)
290{
291 struct compat_cmsghdr __user *cm =
292 (struct compat_cmsghdr __user *)msg->msg_control_user;
293 unsigned int o_flags = (msg->msg_flags & MSG_CMSG_CLOEXEC) ? O_CLOEXEC : 0;
294 int fdmax = min_t(int, scm_max_fds_compat(msg), scm->fp->count);
295 int __user *cmsg_data = CMSG_COMPAT_DATA(cm);
296 int err = 0, i;
297
298 for (i = 0; i < fdmax; i++) {
299 err = scm_recv_one_fd(scm->fp->fp[i], cmsg_data + i, o_flags, notrunc);
300 if (err < 0)
301 break;
302 }
303
304 if (i > 0) {
305 int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
306
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 if (msg->msg_controllen < cmlen)
315 cmlen = msg->msg_controllen;
316 msg->msg_control_user += cmlen;
317 msg->msg_controllen -= cmlen;
318 }
319 }
320
321 if (i < scm->fp->count || (scm->fp->count && fdmax <= 0))
322 msg->msg_flags |= MSG_CTRUNC;
323
324 /*
325 * All of the files that fit in the message have had their usage counts
326 * incremented, so we just free the list.
327 */
328 __scm_destroy(scm);
329}
330
331/* Argument list sizes for compat_sys_socketcall */
332#define AL(x) ((x) * sizeof(u32))
333static unsigned char nas[21] = {
334 AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
335 AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
336 AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
337 AL(4), AL(5), AL(4)
338};
339#undef AL
340
341static inline long __compat_sys_sendmsg(int fd,
342 struct compat_msghdr __user *msg,
343 unsigned int flags)
344{
345 return __sys_sendmsg(fd, (struct user_msghdr __user *)msg,
346 flags | MSG_CMSG_COMPAT, false);
347}
348
349COMPAT_SYSCALL_DEFINE3(sendmsg, int, fd, struct compat_msghdr __user *, msg,
350 unsigned int, flags)
351{
352 return __compat_sys_sendmsg(fd, msg, flags);
353}
354
355static inline long __compat_sys_sendmmsg(int fd,
356 struct compat_mmsghdr __user *mmsg,
357 unsigned int vlen, unsigned int flags)
358{
359 return __sys_sendmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
360 flags | MSG_CMSG_COMPAT, false);
361}
362
363COMPAT_SYSCALL_DEFINE4(sendmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
364 unsigned int, vlen, unsigned int, flags)
365{
366 return __compat_sys_sendmmsg(fd, mmsg, vlen, flags);
367}
368
369static inline long __compat_sys_recvmsg(int fd,
370 struct compat_msghdr __user *msg,
371 unsigned int flags)
372{
373 return __sys_recvmsg(fd, (struct user_msghdr __user *)msg,
374 flags | MSG_CMSG_COMPAT, false);
375}
376
377COMPAT_SYSCALL_DEFINE3(recvmsg, int, fd, struct compat_msghdr __user *, msg,
378 unsigned int, flags)
379{
380 return __compat_sys_recvmsg(fd, msg, flags);
381}
382
383static inline long __compat_sys_recvfrom(int fd, void __user *buf,
384 compat_size_t len, unsigned int flags,
385 struct sockaddr __user *addr,
386 int __user *addrlen)
387{
388 return __sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr,
389 addrlen);
390}
391
392COMPAT_SYSCALL_DEFINE4(recv, int, fd, void __user *, buf, compat_size_t, len, unsigned int, flags)
393{
394 return __compat_sys_recvfrom(fd, buf, len, flags, NULL, NULL);
395}
396
397COMPAT_SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, buf, compat_size_t, len,
398 unsigned int, flags, struct sockaddr __user *, addr,
399 int __user *, addrlen)
400{
401 return __compat_sys_recvfrom(fd, buf, len, flags, addr, addrlen);
402}
403
404COMPAT_SYSCALL_DEFINE5(recvmmsg_time64, int, fd, struct compat_mmsghdr __user *, mmsg,
405 unsigned int, vlen, unsigned int, flags,
406 struct __kernel_timespec __user *, timeout)
407{
408 return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
409 flags | MSG_CMSG_COMPAT, timeout, NULL);
410}
411
412#ifdef CONFIG_COMPAT_32BIT_TIME
413COMPAT_SYSCALL_DEFINE5(recvmmsg_time32, int, fd, struct compat_mmsghdr __user *, mmsg,
414 unsigned int, vlen, unsigned int, flags,
415 struct old_timespec32 __user *, timeout)
416{
417 return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
418 flags | MSG_CMSG_COMPAT, NULL, timeout);
419}
420#endif
421
422COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args)
423{
424 u32 a[AUDITSC_ARGS];
425 unsigned int len;
426 u32 a0, a1;
427 int ret;
428
429 if (call < SYS_SOCKET || call > SYS_SENDMMSG)
430 return -EINVAL;
431 len = nas[call];
432 if (len > sizeof(a))
433 return -EINVAL;
434
435 if (copy_from_user(a, args, len))
436 return -EFAULT;
437
438 ret = audit_socketcall_compat(len / sizeof(a[0]), a);
439 if (ret)
440 return ret;
441
442 a0 = a[0];
443 a1 = a[1];
444
445 switch (call) {
446 case SYS_SOCKET:
447 ret = __sys_socket(a0, a1, a[2]);
448 break;
449 case SYS_BIND:
450 ret = __sys_bind(a0, compat_ptr(a1), a[2]);
451 break;
452 case SYS_CONNECT:
453 ret = __sys_connect(a0, compat_ptr(a1), a[2]);
454 break;
455 case SYS_LISTEN:
456 ret = __sys_listen(a0, a1);
457 break;
458 case SYS_ACCEPT:
459 ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0);
460 break;
461 case SYS_GETSOCKNAME:
462 ret = __sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]), 0);
463 break;
464 case SYS_GETPEERNAME:
465 ret = __sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]), 1);
466 break;
467 case SYS_SOCKETPAIR:
468 ret = __sys_socketpair(a0, a1, a[2], compat_ptr(a[3]));
469 break;
470 case SYS_SEND:
471 ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3], NULL, 0);
472 break;
473 case SYS_SENDTO:
474 ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3],
475 compat_ptr(a[4]), a[5]);
476 break;
477 case SYS_RECV:
478 ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
479 NULL, NULL);
480 break;
481 case SYS_RECVFROM:
482 ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
483 compat_ptr(a[4]),
484 compat_ptr(a[5]));
485 break;
486 case SYS_SHUTDOWN:
487 ret = __sys_shutdown(a0, a1);
488 break;
489 case SYS_SETSOCKOPT:
490 ret = __sys_setsockopt(a0, a1, a[2], compat_ptr(a[3]), a[4]);
491 break;
492 case SYS_GETSOCKOPT:
493 ret = __sys_getsockopt(a0, a1, a[2], compat_ptr(a[3]),
494 compat_ptr(a[4]));
495 break;
496 case SYS_SENDMSG:
497 ret = __compat_sys_sendmsg(a0, compat_ptr(a1), a[2]);
498 break;
499 case SYS_SENDMMSG:
500 ret = __compat_sys_sendmmsg(a0, compat_ptr(a1), a[2], a[3]);
501 break;
502 case SYS_RECVMSG:
503 ret = __compat_sys_recvmsg(a0, compat_ptr(a1), a[2]);
504 break;
505 case SYS_RECVMMSG:
506 ret = __sys_recvmmsg(a0, compat_ptr(a1), a[2],
507 a[3] | MSG_CMSG_COMPAT, NULL,
508 compat_ptr(a[4]));
509 break;
510 case SYS_ACCEPT4:
511 ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]);
512 break;
513 default:
514 ret = -EINVAL;
515 break;
516 }
517 return ret;
518}