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) : \ 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) > 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 = kcmsg_base; 215 kmsg->msg_controllen = kcmlen; 216 return 0; 217 218 Einval: 219 err = -EINVAL; 220 Efault: 221 if (kcmsg_base != (struct cmsghdr *)stackbuf) 222 sock_kfree_s(sk, kcmsg_base, kcmlen); 223 return err; 224 } 225 226 int 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; 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 += cmlen; 278 kmsg->msg_controllen -= cmlen; 279 return 0; 280 } 281 282 static 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 } 288 289 void scm_detach_fds_compat(struct msghdr *msg, struct scm_cookie *scm) 290 { 291 struct compat_cmsghdr __user *cm = 292 (struct compat_cmsghdr __user *)msg->msg_control; 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 = receive_fd_user(scm->fp->fp[i], cmsg_data + i, o_flags); 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 += 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)) 333 static 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 340 341 static 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 } 348 349 COMPAT_SYSCALL_DEFINE3(sendmsg, int, fd, struct compat_msghdr __user *, msg, 350 unsigned int, flags) 351 { 352 return __compat_sys_sendmsg(fd, msg, flags); 353 } 354 355 static 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 } 362 363 COMPAT_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 } 368 369 static 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 } 376 377 COMPAT_SYSCALL_DEFINE3(recvmsg, int, fd, struct compat_msghdr __user *, msg, 378 unsigned int, flags) 379 { 380 return __compat_sys_recvmsg(fd, msg, flags); 381 } 382 383 static 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 } 391 392 COMPAT_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 } 396 397 COMPAT_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 } 403 404 COMPAT_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 413 COMPAT_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 421 422 COMPAT_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])); 463 break; 464 case SYS_GETPEERNAME: 465 ret = __sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2])); 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 } 519