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 ? READ : WRITE, 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) : \ 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))) 123 124 static 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) > 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 */ 138 int 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 = kcmsg_base; 214 kmsg->msg_controllen = kcmlen; 215 return 0; 216 217 Einval: 218 err = -EINVAL; 219 Efault: 220 if (kcmsg_base != (struct cmsghdr *)stackbuf) 221 sock_kfree_s(sk, kcmsg_base, kcmlen); 222 return err; 223 } 224 225 int put_cmsg_compat(struct msghdr *kmsg, int level, int type, int len, void *data) 226 { 227 struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control; 228 struct compat_cmsghdr cmhdr; 229 struct old_timeval32 ctv; 230 struct old_timespec32 cts[3]; 231 int cmlen; 232 233 if (cm == NULL || kmsg->msg_controllen < sizeof(*cm)) { 234 kmsg->msg_flags |= MSG_CTRUNC; 235 return 0; /* XXX: return error? check spec. */ 236 } 237 238 if (!COMPAT_USE_64BIT_TIME) { 239 if (level == SOL_SOCKET && type == SO_TIMESTAMP_OLD) { 240 struct __kernel_old_timeval *tv = (struct __kernel_old_timeval *)data; 241 ctv.tv_sec = tv->tv_sec; 242 ctv.tv_usec = tv->tv_usec; 243 data = &ctv; 244 len = sizeof(ctv); 245 } 246 if (level == SOL_SOCKET && 247 (type == SO_TIMESTAMPNS_OLD || type == SO_TIMESTAMPING_OLD)) { 248 int count = type == SO_TIMESTAMPNS_OLD ? 1 : 3; 249 int i; 250 struct __kernel_old_timespec *ts = data; 251 for (i = 0; i < count; i++) { 252 cts[i].tv_sec = ts[i].tv_sec; 253 cts[i].tv_nsec = ts[i].tv_nsec; 254 } 255 data = &cts; 256 len = sizeof(cts[0]) * count; 257 } 258 } 259 260 cmlen = CMSG_COMPAT_LEN(len); 261 if (kmsg->msg_controllen < cmlen) { 262 kmsg->msg_flags |= MSG_CTRUNC; 263 cmlen = kmsg->msg_controllen; 264 } 265 cmhdr.cmsg_level = level; 266 cmhdr.cmsg_type = type; 267 cmhdr.cmsg_len = cmlen; 268 269 if (copy_to_user(cm, &cmhdr, sizeof cmhdr)) 270 return -EFAULT; 271 if (copy_to_user(CMSG_COMPAT_DATA(cm), data, cmlen - sizeof(struct compat_cmsghdr))) 272 return -EFAULT; 273 cmlen = CMSG_COMPAT_SPACE(len); 274 if (kmsg->msg_controllen < cmlen) 275 cmlen = kmsg->msg_controllen; 276 kmsg->msg_control += cmlen; 277 kmsg->msg_controllen -= cmlen; 278 return 0; 279 } 280 281 static int scm_max_fds_compat(struct msghdr *msg) 282 { 283 if (msg->msg_controllen <= sizeof(struct compat_cmsghdr)) 284 return 0; 285 return (msg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int); 286 } 287 288 void scm_detach_fds_compat(struct msghdr *msg, struct scm_cookie *scm) 289 { 290 struct compat_cmsghdr __user *cm = 291 (struct compat_cmsghdr __user *)msg->msg_control; 292 unsigned int o_flags = (msg->msg_flags & MSG_CMSG_CLOEXEC) ? O_CLOEXEC : 0; 293 int fdmax = min_t(int, scm_max_fds_compat(msg), scm->fp->count); 294 int __user *cmsg_data = CMSG_COMPAT_DATA(cm); 295 int err = 0, i; 296 297 for (i = 0; i < fdmax; i++) { 298 err = receive_fd_user(scm->fp->fp[i], cmsg_data + i, o_flags); 299 if (err < 0) 300 break; 301 } 302 303 if (i > 0) { 304 int cmlen = CMSG_COMPAT_LEN(i * sizeof(int)); 305 306 err = put_user(SOL_SOCKET, &cm->cmsg_level); 307 if (!err) 308 err = put_user(SCM_RIGHTS, &cm->cmsg_type); 309 if (!err) 310 err = put_user(cmlen, &cm->cmsg_len); 311 if (!err) { 312 cmlen = CMSG_COMPAT_SPACE(i * sizeof(int)); 313 if (msg->msg_controllen < cmlen) 314 cmlen = msg->msg_controllen; 315 msg->msg_control += cmlen; 316 msg->msg_controllen -= cmlen; 317 } 318 } 319 320 if (i < scm->fp->count || (scm->fp->count && fdmax <= 0)) 321 msg->msg_flags |= MSG_CTRUNC; 322 323 /* 324 * All of the files that fit in the message have had their usage counts 325 * incremented, so we just free the list. 326 */ 327 __scm_destroy(scm); 328 } 329 330 /* Argument list sizes for compat_sys_socketcall */ 331 #define AL(x) ((x) * sizeof(u32)) 332 static unsigned char nas[21] = { 333 AL(0), AL(3), AL(3), AL(3), AL(2), AL(3), 334 AL(3), AL(3), AL(4), AL(4), AL(4), AL(6), 335 AL(6), AL(2), AL(5), AL(5), AL(3), AL(3), 336 AL(4), AL(5), AL(4) 337 }; 338 #undef AL 339 340 static inline long __compat_sys_sendmsg(int fd, 341 struct compat_msghdr __user *msg, 342 unsigned int flags) 343 { 344 return __sys_sendmsg(fd, (struct user_msghdr __user *)msg, 345 flags | MSG_CMSG_COMPAT, false); 346 } 347 348 COMPAT_SYSCALL_DEFINE3(sendmsg, int, fd, struct compat_msghdr __user *, msg, 349 unsigned int, flags) 350 { 351 return __compat_sys_sendmsg(fd, msg, flags); 352 } 353 354 static inline long __compat_sys_sendmmsg(int fd, 355 struct compat_mmsghdr __user *mmsg, 356 unsigned int vlen, unsigned int flags) 357 { 358 return __sys_sendmmsg(fd, (struct mmsghdr __user *)mmsg, vlen, 359 flags | MSG_CMSG_COMPAT, false); 360 } 361 362 COMPAT_SYSCALL_DEFINE4(sendmmsg, int, fd, struct compat_mmsghdr __user *, mmsg, 363 unsigned int, vlen, unsigned int, flags) 364 { 365 return __compat_sys_sendmmsg(fd, mmsg, vlen, flags); 366 } 367 368 static inline long __compat_sys_recvmsg(int fd, 369 struct compat_msghdr __user *msg, 370 unsigned int flags) 371 { 372 return __sys_recvmsg(fd, (struct user_msghdr __user *)msg, 373 flags | MSG_CMSG_COMPAT, false); 374 } 375 376 COMPAT_SYSCALL_DEFINE3(recvmsg, int, fd, struct compat_msghdr __user *, msg, 377 unsigned int, flags) 378 { 379 return __compat_sys_recvmsg(fd, msg, flags); 380 } 381 382 static inline long __compat_sys_recvfrom(int fd, void __user *buf, 383 compat_size_t len, unsigned int flags, 384 struct sockaddr __user *addr, 385 int __user *addrlen) 386 { 387 return __sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr, 388 addrlen); 389 } 390 391 COMPAT_SYSCALL_DEFINE4(recv, int, fd, void __user *, buf, compat_size_t, len, unsigned int, flags) 392 { 393 return __compat_sys_recvfrom(fd, buf, len, flags, NULL, NULL); 394 } 395 396 COMPAT_SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, buf, compat_size_t, len, 397 unsigned int, flags, struct sockaddr __user *, addr, 398 int __user *, addrlen) 399 { 400 return __compat_sys_recvfrom(fd, buf, len, flags, addr, addrlen); 401 } 402 403 COMPAT_SYSCALL_DEFINE5(recvmmsg_time64, int, fd, struct compat_mmsghdr __user *, mmsg, 404 unsigned int, vlen, unsigned int, flags, 405 struct __kernel_timespec __user *, timeout) 406 { 407 return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen, 408 flags | MSG_CMSG_COMPAT, timeout, NULL); 409 } 410 411 #ifdef CONFIG_COMPAT_32BIT_TIME 412 COMPAT_SYSCALL_DEFINE5(recvmmsg_time32, int, fd, struct compat_mmsghdr __user *, mmsg, 413 unsigned int, vlen, unsigned int, flags, 414 struct old_timespec32 __user *, timeout) 415 { 416 return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen, 417 flags | MSG_CMSG_COMPAT, NULL, timeout); 418 } 419 #endif 420 421 COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args) 422 { 423 u32 a[AUDITSC_ARGS]; 424 unsigned int len; 425 u32 a0, a1; 426 int ret; 427 428 if (call < SYS_SOCKET || call > SYS_SENDMMSG) 429 return -EINVAL; 430 len = nas[call]; 431 if (len > sizeof(a)) 432 return -EINVAL; 433 434 if (copy_from_user(a, args, len)) 435 return -EFAULT; 436 437 ret = audit_socketcall_compat(len / sizeof(a[0]), a); 438 if (ret) 439 return ret; 440 441 a0 = a[0]; 442 a1 = a[1]; 443 444 switch (call) { 445 case SYS_SOCKET: 446 ret = __sys_socket(a0, a1, a[2]); 447 break; 448 case SYS_BIND: 449 ret = __sys_bind(a0, compat_ptr(a1), a[2]); 450 break; 451 case SYS_CONNECT: 452 ret = __sys_connect(a0, compat_ptr(a1), a[2]); 453 break; 454 case SYS_LISTEN: 455 ret = __sys_listen(a0, a1); 456 break; 457 case SYS_ACCEPT: 458 ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0); 459 break; 460 case SYS_GETSOCKNAME: 461 ret = __sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2])); 462 break; 463 case SYS_GETPEERNAME: 464 ret = __sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2])); 465 break; 466 case SYS_SOCKETPAIR: 467 ret = __sys_socketpair(a0, a1, a[2], compat_ptr(a[3])); 468 break; 469 case SYS_SEND: 470 ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3], NULL, 0); 471 break; 472 case SYS_SENDTO: 473 ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3], 474 compat_ptr(a[4]), a[5]); 475 break; 476 case SYS_RECV: 477 ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3], 478 NULL, NULL); 479 break; 480 case SYS_RECVFROM: 481 ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3], 482 compat_ptr(a[4]), 483 compat_ptr(a[5])); 484 break; 485 case SYS_SHUTDOWN: 486 ret = __sys_shutdown(a0, a1); 487 break; 488 case SYS_SETSOCKOPT: 489 ret = __sys_setsockopt(a0, a1, a[2], compat_ptr(a[3]), a[4]); 490 break; 491 case SYS_GETSOCKOPT: 492 ret = __sys_getsockopt(a0, a1, a[2], compat_ptr(a[3]), 493 compat_ptr(a[4])); 494 break; 495 case SYS_SENDMSG: 496 ret = __compat_sys_sendmsg(a0, compat_ptr(a1), a[2]); 497 break; 498 case SYS_SENDMMSG: 499 ret = __compat_sys_sendmmsg(a0, compat_ptr(a1), a[2], a[3]); 500 break; 501 case SYS_RECVMSG: 502 ret = __compat_sys_recvmsg(a0, compat_ptr(a1), a[2]); 503 break; 504 case SYS_RECVMMSG: 505 ret = __sys_recvmmsg(a0, compat_ptr(a1), a[2], 506 a[3] | MSG_CMSG_COMPAT, NULL, 507 compat_ptr(a[4])); 508 break; 509 case SYS_ACCEPT4: 510 ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]); 511 break; 512 default: 513 ret = -EINVAL; 514 break; 515 } 516 return ret; 517 } 518