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 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 } 227 228 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 } 283 284 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 } 290 291 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 342 343 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 } 350 351 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 } 356 357 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 } 364 365 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 } 370 371 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 } 378 379 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 } 384 385 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 } 393 394 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 } 398 399 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 } 405 406 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 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 423 424 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