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
__get_compat_msghdr(struct msghdr * kmsg,struct compat_msghdr __user * umsg,struct sockaddr __user ** save_addr,compat_uptr_t * ptr,compat_size_t * len)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
get_compat_msghdr(struct msghdr * kmsg,struct compat_msghdr __user * umsg,struct sockaddr __user ** save_addr,struct iovec ** iov)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 = import_iovec(save_addr ? READ : WRITE, compat_ptr(ptr), len,
102 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
cmsg_compat_nxthdr(struct msghdr * msg,struct compat_cmsghdr __user * cmsg,int cmsg_len)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 */
cmsghdr_from_user_compat_to_kern(struct msghdr * kmsg,struct sock * sk,unsigned char * stackbuf,int stackbuf_size)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 -ENOMEM;
181
182 /* Now copy them over neatly. */
183 memset(kcmsg, 0, kcmlen);
184 ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
185 while (ucmsg != NULL) {
186 struct compat_cmsghdr cmsg;
187 if (copy_from_user(&cmsg, ucmsg, sizeof(cmsg)))
188 goto Efault;
189 if (!CMSG_COMPAT_OK(cmsg.cmsg_len, ucmsg, kmsg))
190 goto Einval;
191 tmp = ((cmsg.cmsg_len - sizeof(*ucmsg)) + sizeof(struct cmsghdr));
192 if ((char *)kcmsg_base + kcmlen - (char *)kcmsg < CMSG_ALIGN(tmp))
193 goto Einval;
194 kcmsg->cmsg_len = tmp;
195 kcmsg->cmsg_level = cmsg.cmsg_level;
196 kcmsg->cmsg_type = cmsg.cmsg_type;
197 tmp = CMSG_ALIGN(tmp);
198 if (copy_from_user(CMSG_DATA(kcmsg),
199 CMSG_COMPAT_DATA(ucmsg),
200 (cmsg.cmsg_len - sizeof(*ucmsg))))
201 goto Efault;
202
203 /* Advance. */
204 kcmsg = (struct cmsghdr *)((char *)kcmsg + tmp);
205 ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, cmsg.cmsg_len);
206 }
207
208 /*
209 * check the length of messages copied in is the same as the
210 * what we get from the first loop
211 */
212 if ((char *)kcmsg - (char *)kcmsg_base != kcmlen)
213 goto Einval;
214
215 /* Ok, looks like we made it. Hook it up and return success. */
216 kmsg->msg_control = kcmsg_base;
217 kmsg->msg_controllen = kcmlen;
218 return 0;
219
220 Einval:
221 err = -EINVAL;
222 Efault:
223 if (kcmsg_base != (struct cmsghdr *)stackbuf)
224 sock_kfree_s(sk, kcmsg_base, kcmlen);
225 return err;
226 }
227
put_cmsg_compat(struct msghdr * kmsg,int level,int type,int len,void * data)228 int put_cmsg_compat(struct msghdr *kmsg, int level, int type, int len, void *data)
229 {
230 struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
231 struct compat_cmsghdr cmhdr;
232 struct old_timeval32 ctv;
233 struct old_timespec32 cts[3];
234 int cmlen;
235
236 if (cm == NULL || kmsg->msg_controllen < sizeof(*cm)) {
237 kmsg->msg_flags |= MSG_CTRUNC;
238 return 0; /* XXX: return error? check spec. */
239 }
240
241 if (!COMPAT_USE_64BIT_TIME) {
242 if (level == SOL_SOCKET && type == SO_TIMESTAMP_OLD) {
243 struct __kernel_old_timeval *tv = (struct __kernel_old_timeval *)data;
244 ctv.tv_sec = tv->tv_sec;
245 ctv.tv_usec = tv->tv_usec;
246 data = &ctv;
247 len = sizeof(ctv);
248 }
249 if (level == SOL_SOCKET &&
250 (type == SO_TIMESTAMPNS_OLD || type == SO_TIMESTAMPING_OLD)) {
251 int count = type == SO_TIMESTAMPNS_OLD ? 1 : 3;
252 int i;
253 struct __kernel_old_timespec *ts = data;
254 for (i = 0; i < count; i++) {
255 cts[i].tv_sec = ts[i].tv_sec;
256 cts[i].tv_nsec = ts[i].tv_nsec;
257 }
258 data = &cts;
259 len = sizeof(cts[0]) * count;
260 }
261 }
262
263 cmlen = CMSG_COMPAT_LEN(len);
264 if (kmsg->msg_controllen < cmlen) {
265 kmsg->msg_flags |= MSG_CTRUNC;
266 cmlen = kmsg->msg_controllen;
267 }
268 cmhdr.cmsg_level = level;
269 cmhdr.cmsg_type = type;
270 cmhdr.cmsg_len = cmlen;
271
272 if (copy_to_user(cm, &cmhdr, sizeof cmhdr))
273 return -EFAULT;
274 if (copy_to_user(CMSG_COMPAT_DATA(cm), data, cmlen - sizeof(struct compat_cmsghdr)))
275 return -EFAULT;
276 cmlen = CMSG_COMPAT_SPACE(len);
277 if (kmsg->msg_controllen < cmlen)
278 cmlen = kmsg->msg_controllen;
279 kmsg->msg_control += cmlen;
280 kmsg->msg_controllen -= cmlen;
281 return 0;
282 }
283
scm_max_fds_compat(struct msghdr * msg)284 static int scm_max_fds_compat(struct msghdr *msg)
285 {
286 if (msg->msg_controllen <= sizeof(struct compat_cmsghdr))
287 return 0;
288 return (msg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int);
289 }
290
scm_detach_fds_compat(struct msghdr * msg,struct scm_cookie * scm)291 void scm_detach_fds_compat(struct msghdr *msg, struct scm_cookie *scm)
292 {
293 struct compat_cmsghdr __user *cm =
294 (struct compat_cmsghdr __user *)msg->msg_control;
295 unsigned int o_flags = (msg->msg_flags & MSG_CMSG_CLOEXEC) ? O_CLOEXEC : 0;
296 int fdmax = min_t(int, scm_max_fds_compat(msg), scm->fp->count);
297 int __user *cmsg_data = CMSG_COMPAT_DATA(cm);
298 int err = 0, i;
299
300 for (i = 0; i < fdmax; i++) {
301 err = receive_fd_user(scm->fp->fp[i], cmsg_data + i, o_flags);
302 if (err < 0)
303 break;
304 }
305
306 if (i > 0) {
307 int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
308
309 err = put_user(SOL_SOCKET, &cm->cmsg_level);
310 if (!err)
311 err = put_user(SCM_RIGHTS, &cm->cmsg_type);
312 if (!err)
313 err = put_user(cmlen, &cm->cmsg_len);
314 if (!err) {
315 cmlen = CMSG_COMPAT_SPACE(i * sizeof(int));
316 if (msg->msg_controllen < cmlen)
317 cmlen = msg->msg_controllen;
318 msg->msg_control += cmlen;
319 msg->msg_controllen -= cmlen;
320 }
321 }
322
323 if (i < scm->fp->count || (scm->fp->count && fdmax <= 0))
324 msg->msg_flags |= MSG_CTRUNC;
325
326 /*
327 * All of the files that fit in the message have had their usage counts
328 * incremented, so we just free the list.
329 */
330 __scm_destroy(scm);
331 }
332
333 /* Argument list sizes for compat_sys_socketcall */
334 #define AL(x) ((x) * sizeof(u32))
335 static unsigned char nas[21] = {
336 AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
337 AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
338 AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
339 AL(4), AL(5), AL(4)
340 };
341 #undef AL
342
__compat_sys_sendmsg(int fd,struct compat_msghdr __user * msg,unsigned int flags)343 static inline long __compat_sys_sendmsg(int fd,
344 struct compat_msghdr __user *msg,
345 unsigned int flags)
346 {
347 return __sys_sendmsg(fd, (struct user_msghdr __user *)msg,
348 flags | MSG_CMSG_COMPAT, false);
349 }
350
COMPAT_SYSCALL_DEFINE3(sendmsg,int,fd,struct compat_msghdr __user *,msg,unsigned int,flags)351 COMPAT_SYSCALL_DEFINE3(sendmsg, int, fd, struct compat_msghdr __user *, msg,
352 unsigned int, flags)
353 {
354 return __compat_sys_sendmsg(fd, msg, flags);
355 }
356
__compat_sys_sendmmsg(int fd,struct compat_mmsghdr __user * mmsg,unsigned int vlen,unsigned int flags)357 static inline long __compat_sys_sendmmsg(int fd,
358 struct compat_mmsghdr __user *mmsg,
359 unsigned int vlen, unsigned int flags)
360 {
361 return __sys_sendmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
362 flags | MSG_CMSG_COMPAT, false);
363 }
364
COMPAT_SYSCALL_DEFINE4(sendmmsg,int,fd,struct compat_mmsghdr __user *,mmsg,unsigned int,vlen,unsigned int,flags)365 COMPAT_SYSCALL_DEFINE4(sendmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
366 unsigned int, vlen, unsigned int, flags)
367 {
368 return __compat_sys_sendmmsg(fd, mmsg, vlen, flags);
369 }
370
__compat_sys_recvmsg(int fd,struct compat_msghdr __user * msg,unsigned int flags)371 static inline long __compat_sys_recvmsg(int fd,
372 struct compat_msghdr __user *msg,
373 unsigned int flags)
374 {
375 return __sys_recvmsg(fd, (struct user_msghdr __user *)msg,
376 flags | MSG_CMSG_COMPAT, false);
377 }
378
COMPAT_SYSCALL_DEFINE3(recvmsg,int,fd,struct compat_msghdr __user *,msg,unsigned int,flags)379 COMPAT_SYSCALL_DEFINE3(recvmsg, int, fd, struct compat_msghdr __user *, msg,
380 unsigned int, flags)
381 {
382 return __compat_sys_recvmsg(fd, msg, flags);
383 }
384
__compat_sys_recvfrom(int fd,void __user * buf,compat_size_t len,unsigned int flags,struct sockaddr __user * addr,int __user * addrlen)385 static inline long __compat_sys_recvfrom(int fd, void __user *buf,
386 compat_size_t len, unsigned int flags,
387 struct sockaddr __user *addr,
388 int __user *addrlen)
389 {
390 return __sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr,
391 addrlen);
392 }
393
COMPAT_SYSCALL_DEFINE4(recv,int,fd,void __user *,buf,compat_size_t,len,unsigned int,flags)394 COMPAT_SYSCALL_DEFINE4(recv, int, fd, void __user *, buf, compat_size_t, len, unsigned int, flags)
395 {
396 return __compat_sys_recvfrom(fd, buf, len, flags, NULL, NULL);
397 }
398
COMPAT_SYSCALL_DEFINE6(recvfrom,int,fd,void __user *,buf,compat_size_t,len,unsigned int,flags,struct sockaddr __user *,addr,int __user *,addrlen)399 COMPAT_SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, buf, compat_size_t, len,
400 unsigned int, flags, struct sockaddr __user *, addr,
401 int __user *, addrlen)
402 {
403 return __compat_sys_recvfrom(fd, buf, len, flags, addr, addrlen);
404 }
405
COMPAT_SYSCALL_DEFINE5(recvmmsg_time64,int,fd,struct compat_mmsghdr __user *,mmsg,unsigned int,vlen,unsigned int,flags,struct __kernel_timespec __user *,timeout)406 COMPAT_SYSCALL_DEFINE5(recvmmsg_time64, int, fd, struct compat_mmsghdr __user *, mmsg,
407 unsigned int, vlen, unsigned int, flags,
408 struct __kernel_timespec __user *, timeout)
409 {
410 return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
411 flags | MSG_CMSG_COMPAT, timeout, NULL);
412 }
413
414 #ifdef CONFIG_COMPAT_32BIT_TIME
COMPAT_SYSCALL_DEFINE5(recvmmsg_time32,int,fd,struct compat_mmsghdr __user *,mmsg,unsigned int,vlen,unsigned int,flags,struct old_timespec32 __user *,timeout)415 COMPAT_SYSCALL_DEFINE5(recvmmsg_time32, int, fd, struct compat_mmsghdr __user *, mmsg,
416 unsigned int, vlen, unsigned int, flags,
417 struct old_timespec32 __user *, timeout)
418 {
419 return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
420 flags | MSG_CMSG_COMPAT, NULL, timeout);
421 }
422 #endif
423
COMPAT_SYSCALL_DEFINE2(socketcall,int,call,u32 __user *,args)424 COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args)
425 {
426 u32 a[AUDITSC_ARGS];
427 unsigned int len;
428 u32 a0, a1;
429 int ret;
430
431 if (call < SYS_SOCKET || call > SYS_SENDMMSG)
432 return -EINVAL;
433 len = nas[call];
434 if (len > sizeof(a))
435 return -EINVAL;
436
437 if (copy_from_user(a, args, len))
438 return -EFAULT;
439
440 ret = audit_socketcall_compat(len / sizeof(a[0]), a);
441 if (ret)
442 return ret;
443
444 a0 = a[0];
445 a1 = a[1];
446
447 switch (call) {
448 case SYS_SOCKET:
449 ret = __sys_socket(a0, a1, a[2]);
450 break;
451 case SYS_BIND:
452 ret = __sys_bind(a0, compat_ptr(a1), a[2]);
453 break;
454 case SYS_CONNECT:
455 ret = __sys_connect(a0, compat_ptr(a1), a[2]);
456 break;
457 case SYS_LISTEN:
458 ret = __sys_listen(a0, a1);
459 break;
460 case SYS_ACCEPT:
461 ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0);
462 break;
463 case SYS_GETSOCKNAME:
464 ret = __sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]));
465 break;
466 case SYS_GETPEERNAME:
467 ret = __sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2]));
468 break;
469 case SYS_SOCKETPAIR:
470 ret = __sys_socketpair(a0, a1, a[2], compat_ptr(a[3]));
471 break;
472 case SYS_SEND:
473 ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3], NULL, 0);
474 break;
475 case SYS_SENDTO:
476 ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3],
477 compat_ptr(a[4]), a[5]);
478 break;
479 case SYS_RECV:
480 ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
481 NULL, NULL);
482 break;
483 case SYS_RECVFROM:
484 ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
485 compat_ptr(a[4]),
486 compat_ptr(a[5]));
487 break;
488 case SYS_SHUTDOWN:
489 ret = __sys_shutdown(a0, a1);
490 break;
491 case SYS_SETSOCKOPT:
492 ret = __sys_setsockopt(a0, a1, a[2], compat_ptr(a[3]), a[4]);
493 break;
494 case SYS_GETSOCKOPT:
495 ret = __sys_getsockopt(a0, a1, a[2], compat_ptr(a[3]),
496 compat_ptr(a[4]));
497 break;
498 case SYS_SENDMSG:
499 ret = __compat_sys_sendmsg(a0, compat_ptr(a1), a[2]);
500 break;
501 case SYS_SENDMMSG:
502 ret = __compat_sys_sendmmsg(a0, compat_ptr(a1), a[2], a[3]);
503 break;
504 case SYS_RECVMSG:
505 ret = __compat_sys_recvmsg(a0, compat_ptr(a1), a[2]);
506 break;
507 case SYS_RECVMMSG:
508 ret = __sys_recvmmsg(a0, compat_ptr(a1), a[2],
509 a[3] | MSG_CMSG_COMPAT, NULL,
510 compat_ptr(a[4]));
511 break;
512 case SYS_ACCEPT4:
513 ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]);
514 break;
515 default:
516 ret = -EINVAL;
517 break;
518 }
519 return ret;
520 }
521