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 *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_iocb = NULL;
79 kmsg->msg_ubuf = NULL;
80 return 0;
81 }
82
83 int get_compat_msghdr(struct msghdr *kmsg,
84 struct compat_msghdr __user *umsg,
85 struct sockaddr __user **save_addr,
86 struct iovec **iov)
87 {
88 struct compat_msghdr msg;
89 ssize_t err;
90
91 if (copy_from_user(&msg, umsg, sizeof(*umsg)))
92 return -EFAULT;
93
94 err = __get_compat_msghdr(kmsg, &msg, save_addr);
95 if (err)
96 return err;
97
98 err = import_iovec(save_addr ? ITER_DEST : ITER_SOURCE,
99 compat_ptr(msg.msg_iov), msg.msg_iovlen,
100 UIO_FASTIOV, iov, &kmsg->msg_iter);
101 return err < 0 ? err : 0;
102 }
103
104 /* Bleech... */
105 #define CMSG_COMPAT_ALIGN(len) ALIGN((len), sizeof(s32))
106
107 #define CMSG_COMPAT_DATA(cmsg) \
108 ((void __user *)((char __user *)(cmsg) + sizeof(struct compat_cmsghdr)))
109 #define CMSG_COMPAT_SPACE(len) \
110 (sizeof(struct compat_cmsghdr) + CMSG_COMPAT_ALIGN(len))
111 #define CMSG_COMPAT_LEN(len) \
112 (sizeof(struct compat_cmsghdr) + (len))
113
114 #define CMSG_COMPAT_FIRSTHDR(msg) \
115 (((msg)->msg_controllen) >= sizeof(struct compat_cmsghdr) ? \
116 (struct compat_cmsghdr __user *)((msg)->msg_control_user) : \
117 (struct compat_cmsghdr __user *)NULL)
118
119 #define CMSG_COMPAT_OK(ucmlen, ucmsg, mhdr) \
120 ((ucmlen) >= sizeof(struct compat_cmsghdr) && \
121 (ucmlen) <= (unsigned long) \
122 ((mhdr)->msg_controllen - \
123 ((char __user *)(ucmsg) - (char __user *)(mhdr)->msg_control_user)))
124
125 static inline struct compat_cmsghdr __user *cmsg_compat_nxthdr(struct msghdr *msg,
126 struct compat_cmsghdr __user *cmsg, int cmsg_len)
127 {
128 char __user *ptr = (char __user *)cmsg + CMSG_COMPAT_ALIGN(cmsg_len);
129 if ((unsigned long)(ptr + 1 - (char __user *)msg->msg_control_user) >
130 msg->msg_controllen)
131 return NULL;
132 return (struct compat_cmsghdr __user *)ptr;
133 }
134
135 /* There is a lot of hair here because the alignment rules (and
136 * thus placement) of cmsg headers and length are different for
137 * 32-bit apps. -DaveM
138 */
139 int cmsghdr_from_user_compat_to_kern(struct msghdr *kmsg, struct sock *sk,
140 unsigned char *stackbuf, int stackbuf_size)
141 {
142 struct compat_cmsghdr __user *ucmsg;
143 struct cmsghdr *kcmsg, *kcmsg_base;
144 compat_size_t ucmlen;
145 __kernel_size_t kcmlen, tmp;
146 int err = -EFAULT;
147
148 BUILD_BUG_ON(sizeof(struct compat_cmsghdr) !=
149 CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)));
150
151 kcmlen = 0;
152 kcmsg_base = kcmsg = (struct cmsghdr *)stackbuf;
153 ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
154 while (ucmsg != NULL) {
155 if (get_user(ucmlen, &ucmsg->cmsg_len))
156 return -EFAULT;
157
158 /* Catch bogons. */
159 if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
160 return -EINVAL;
161
162 tmp = ((ucmlen - sizeof(*ucmsg)) + sizeof(struct cmsghdr));
163 tmp = CMSG_ALIGN(tmp);
164 kcmlen += tmp;
165 ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
166 }
167 if (kcmlen == 0)
168 return -EINVAL;
169
170 /* The kcmlen holds the 64-bit version of the control length.
171 * It may not be modified as we do not stick it into the kmsg
172 * until we have successfully copied over all of the data
173 * from the user.
174 */
175 if (kcmlen > stackbuf_size)
176 kcmsg_base = kcmsg = sock_kmalloc(sk, kcmlen, GFP_KERNEL);
177 if (kcmsg == NULL)
178 return -ENOMEM;
179
180 /* Now copy them over neatly. */
181 memset(kcmsg, 0, kcmlen);
182 ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
183 while (ucmsg != NULL) {
184 struct compat_cmsghdr cmsg;
185 if (copy_from_user(&cmsg, ucmsg, sizeof(cmsg)))
186 goto Efault;
187 if (!CMSG_COMPAT_OK(cmsg.cmsg_len, ucmsg, kmsg))
188 goto Einval;
189 tmp = ((cmsg.cmsg_len - sizeof(*ucmsg)) + sizeof(struct cmsghdr));
190 if ((char *)kcmsg_base + kcmlen - (char *)kcmsg < CMSG_ALIGN(tmp))
191 goto Einval;
192 kcmsg->cmsg_len = tmp;
193 kcmsg->cmsg_level = cmsg.cmsg_level;
194 kcmsg->cmsg_type = cmsg.cmsg_type;
195 tmp = CMSG_ALIGN(tmp);
196 if (copy_from_user(CMSG_DATA(kcmsg),
197 CMSG_COMPAT_DATA(ucmsg),
198 (cmsg.cmsg_len - sizeof(*ucmsg))))
199 goto Efault;
200
201 /* Advance. */
202 kcmsg = (struct cmsghdr *)((char *)kcmsg + tmp);
203 ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, cmsg.cmsg_len);
204 }
205
206 /*
207 * check the length of messages copied in is the same as the
208 * what we get from the first loop
209 */
210 if ((char *)kcmsg - (char *)kcmsg_base != kcmlen)
211 goto Einval;
212
213 /* Ok, looks like we made it. Hook it up and return success. */
214 kmsg->msg_control_is_user = false;
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_user;
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_user += cmlen;
279 kmsg->msg_controllen -= cmlen;
280 return 0;
281 }
282
283 static int scm_max_fds_compat(struct msghdr *msg)
284 {
285 if (msg->msg_controllen <= sizeof(struct compat_cmsghdr))
286 return 0;
287 return (msg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int);
288 }
289
290 void scm_detach_fds_compat(struct msghdr *msg, struct scm_cookie *scm)
291 {
292 struct compat_cmsghdr __user *cm =
293 (struct compat_cmsghdr __user *)msg->msg_control_user;
294 unsigned int o_flags = (msg->msg_flags & MSG_CMSG_CLOEXEC) ? O_CLOEXEC : 0;
295 int fdmax = min_t(int, scm_max_fds_compat(msg), scm->fp->count);
296 int __user *cmsg_data = CMSG_COMPAT_DATA(cm);
297 int err = 0, i;
298
299 for (i = 0; i < fdmax; i++) {
300 err = scm_recv_one_fd(scm->fp->fp[i], cmsg_data + i, o_flags);
301 if (err < 0)
302 break;
303 }
304
305 if (i > 0) {
306 int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
307
308 err = put_user(SOL_SOCKET, &cm->cmsg_level);
309 if (!err)
310 err = put_user(SCM_RIGHTS, &cm->cmsg_type);
311 if (!err)
312 err = put_user(cmlen, &cm->cmsg_len);
313 if (!err) {
314 cmlen = CMSG_COMPAT_SPACE(i * sizeof(int));
315 if (msg->msg_controllen < cmlen)
316 cmlen = msg->msg_controllen;
317 msg->msg_control_user += cmlen;
318 msg->msg_controllen -= cmlen;
319 }
320 }
321
322 if (i < scm->fp->count || (scm->fp->count && fdmax <= 0))
323 msg->msg_flags |= MSG_CTRUNC;
324
325 /*
326 * All of the files that fit in the message have had their usage counts
327 * incremented, so we just free the list.
328 */
329 __scm_destroy(scm);
330 }
331
332 /* Argument list sizes for compat_sys_socketcall */
333 #define AL(x) ((x) * sizeof(u32))
334 static unsigned char nas[21] = {
335 AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
336 AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
337 AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
338 AL(4), AL(5), AL(4)
339 };
340 #undef AL
341
342 static inline long __compat_sys_sendmsg(int fd,
343 struct compat_msghdr __user *msg,
344 unsigned int flags)
345 {
346 return __sys_sendmsg(fd, (struct user_msghdr __user *)msg,
347 flags | MSG_CMSG_COMPAT, false);
348 }
349
350 COMPAT_SYSCALL_DEFINE3(sendmsg, int, fd, struct compat_msghdr __user *, msg,
351 unsigned int, flags)
352 {
353 return __compat_sys_sendmsg(fd, msg, flags);
354 }
355
356 static inline long __compat_sys_sendmmsg(int fd,
357 struct compat_mmsghdr __user *mmsg,
358 unsigned int vlen, unsigned int flags)
359 {
360 return __sys_sendmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
361 flags | MSG_CMSG_COMPAT, false);
362 }
363
364 COMPAT_SYSCALL_DEFINE4(sendmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
365 unsigned int, vlen, unsigned int, flags)
366 {
367 return __compat_sys_sendmmsg(fd, mmsg, vlen, flags);
368 }
369
370 static inline long __compat_sys_recvmsg(int fd,
371 struct compat_msghdr __user *msg,
372 unsigned int flags)
373 {
374 return __sys_recvmsg(fd, (struct user_msghdr __user *)msg,
375 flags | MSG_CMSG_COMPAT, false);
376 }
377
378 COMPAT_SYSCALL_DEFINE3(recvmsg, int, fd, struct compat_msghdr __user *, msg,
379 unsigned int, flags)
380 {
381 return __compat_sys_recvmsg(fd, msg, flags);
382 }
383
384 static inline long __compat_sys_recvfrom(int fd, void __user *buf,
385 compat_size_t len, unsigned int flags,
386 struct sockaddr __user *addr,
387 int __user *addrlen)
388 {
389 return __sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr,
390 addrlen);
391 }
392
393 COMPAT_SYSCALL_DEFINE4(recv, int, fd, void __user *, buf, compat_size_t, len, unsigned int, flags)
394 {
395 return __compat_sys_recvfrom(fd, buf, len, flags, NULL, NULL);
396 }
397
398 COMPAT_SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, buf, compat_size_t, len,
399 unsigned int, flags, struct sockaddr __user *, addr,
400 int __user *, addrlen)
401 {
402 return __compat_sys_recvfrom(fd, buf, len, flags, addr, addrlen);
403 }
404
405 COMPAT_SYSCALL_DEFINE5(recvmmsg_time64, int, fd, struct compat_mmsghdr __user *, mmsg,
406 unsigned int, vlen, unsigned int, flags,
407 struct __kernel_timespec __user *, timeout)
408 {
409 return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
410 flags | MSG_CMSG_COMPAT, timeout, NULL);
411 }
412
413 #ifdef CONFIG_COMPAT_32BIT_TIME
414 COMPAT_SYSCALL_DEFINE5(recvmmsg_time32, int, fd, struct compat_mmsghdr __user *, mmsg,
415 unsigned int, vlen, unsigned int, flags,
416 struct old_timespec32 __user *, timeout)
417 {
418 return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
419 flags | MSG_CMSG_COMPAT, NULL, timeout);
420 }
421 #endif
422
423 COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args)
424 {
425 u32 a[AUDITSC_ARGS];
426 unsigned int len;
427 u32 a0, a1;
428 int ret;
429
430 if (call < SYS_SOCKET || call > SYS_SENDMMSG)
431 return -EINVAL;
432 len = nas[call];
433 if (len > sizeof(a))
434 return -EINVAL;
435
436 if (copy_from_user(a, args, len))
437 return -EFAULT;
438
439 ret = audit_socketcall_compat(len / sizeof(a[0]), a);
440 if (ret)
441 return ret;
442
443 a0 = a[0];
444 a1 = a[1];
445
446 switch (call) {
447 case SYS_SOCKET:
448 ret = __sys_socket(a0, a1, a[2]);
449 break;
450 case SYS_BIND:
451 ret = __sys_bind(a0, compat_ptr(a1), a[2]);
452 break;
453 case SYS_CONNECT:
454 ret = __sys_connect(a0, compat_ptr(a1), a[2]);
455 break;
456 case SYS_LISTEN:
457 ret = __sys_listen(a0, a1);
458 break;
459 case SYS_ACCEPT:
460 ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0);
461 break;
462 case SYS_GETSOCKNAME:
463 ret = __sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]));
464 break;
465 case SYS_GETPEERNAME:
466 ret = __sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2]));
467 break;
468 case SYS_SOCKETPAIR:
469 ret = __sys_socketpair(a0, a1, a[2], compat_ptr(a[3]));
470 break;
471 case SYS_SEND:
472 ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3], NULL, 0);
473 break;
474 case SYS_SENDTO:
475 ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3],
476 compat_ptr(a[4]), a[5]);
477 break;
478 case SYS_RECV:
479 ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
480 NULL, NULL);
481 break;
482 case SYS_RECVFROM:
483 ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
484 compat_ptr(a[4]),
485 compat_ptr(a[5]));
486 break;
487 case SYS_SHUTDOWN:
488 ret = __sys_shutdown(a0, a1);
489 break;
490 case SYS_SETSOCKOPT:
491 ret = __sys_setsockopt(a0, a1, a[2], compat_ptr(a[3]), a[4]);
492 break;
493 case SYS_GETSOCKOPT:
494 ret = __sys_getsockopt(a0, a1, a[2], compat_ptr(a[3]),
495 compat_ptr(a[4]));
496 break;
497 case SYS_SENDMSG:
498 ret = __compat_sys_sendmsg(a0, compat_ptr(a1), a[2]);
499 break;
500 case SYS_SENDMMSG:
501 ret = __compat_sys_sendmmsg(a0, compat_ptr(a1), a[2], a[3]);
502 break;
503 case SYS_RECVMSG:
504 ret = __compat_sys_recvmsg(a0, compat_ptr(a1), a[2]);
505 break;
506 case SYS_RECVMMSG:
507 ret = __sys_recvmmsg(a0, compat_ptr(a1), a[2],
508 a[3] | MSG_CMSG_COMPAT, NULL,
509 compat_ptr(a[4]));
510 break;
511 case SYS_ACCEPT4:
512 ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]);
513 break;
514 default:
515 ret = -EINVAL;
516 break;
517 }
518 return ret;
519 }
520
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