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_control_user = compat_ptr(msg->msg_control); 56 kmsg->msg_controllen = msg->msg_controllen; 57 58 if (save_addr) 59 *save_addr = compat_ptr(msg->msg_name); 60 61 if (msg->msg_name && kmsg->msg_namelen) { 62 if (!save_addr) { 63 err = move_addr_to_kernel(compat_ptr(msg->msg_name), 64 kmsg->msg_namelen, 65 kmsg->msg_name); 66 if (err < 0) 67 return err; 68 } 69 } else { 70 kmsg->msg_name = NULL; 71 kmsg->msg_namelen = 0; 72 } 73 74 if (msg->msg_iovlen > UIO_MAXIOV) 75 return -EMSGSIZE; 76 77 kmsg->msg_iocb = NULL; 78 kmsg->msg_ubuf = NULL; 79 return 0; 80 } 81 82 int get_compat_msghdr(struct msghdr *kmsg, 83 struct compat_msghdr __user *umsg, 84 struct sockaddr __user **save_addr, 85 struct iovec **iov) 86 { 87 struct compat_msghdr msg; 88 ssize_t err; 89 90 if (copy_from_user(&msg, umsg, sizeof(*umsg))) 91 return -EFAULT; 92 93 err = __get_compat_msghdr(kmsg, &msg, save_addr); 94 if (err) 95 return err; 96 97 err = import_iovec(save_addr ? READ : WRITE, compat_ptr(msg.msg_iov), msg.msg_iovlen, 98 UIO_FASTIOV, iov, &kmsg->msg_iter); 99 return err < 0 ? err : 0; 100 } 101 102 /* Bleech... */ 103 #define CMSG_COMPAT_ALIGN(len) ALIGN((len), sizeof(s32)) 104 105 #define CMSG_COMPAT_DATA(cmsg) \ 106 ((void __user *)((char __user *)(cmsg) + sizeof(struct compat_cmsghdr))) 107 #define CMSG_COMPAT_SPACE(len) \ 108 (sizeof(struct compat_cmsghdr) + CMSG_COMPAT_ALIGN(len)) 109 #define CMSG_COMPAT_LEN(len) \ 110 (sizeof(struct compat_cmsghdr) + (len)) 111 112 #define CMSG_COMPAT_FIRSTHDR(msg) \ 113 (((msg)->msg_controllen) >= sizeof(struct compat_cmsghdr) ? \ 114 (struct compat_cmsghdr __user *)((msg)->msg_control) : \ 115 (struct compat_cmsghdr __user *)NULL) 116 117 #define CMSG_COMPAT_OK(ucmlen, ucmsg, mhdr) \ 118 ((ucmlen) >= sizeof(struct compat_cmsghdr) && \ 119 (ucmlen) <= (unsigned long) \ 120 ((mhdr)->msg_controllen - \ 121 ((char __user *)(ucmsg) - (char __user *)(mhdr)->msg_control_user))) 122 123 static inline struct compat_cmsghdr __user *cmsg_compat_nxthdr(struct msghdr *msg, 124 struct compat_cmsghdr __user *cmsg, int cmsg_len) 125 { 126 char __user *ptr = (char __user *)cmsg + CMSG_COMPAT_ALIGN(cmsg_len); 127 if ((unsigned long)(ptr + 1 - (char __user *)msg->msg_control) > 128 msg->msg_controllen) 129 return NULL; 130 return (struct compat_cmsghdr __user *)ptr; 131 } 132 133 /* There is a lot of hair here because the alignment rules (and 134 * thus placement) of cmsg headers and length are different for 135 * 32-bit apps. -DaveM 136 */ 137 int cmsghdr_from_user_compat_to_kern(struct msghdr *kmsg, struct sock *sk, 138 unsigned char *stackbuf, int stackbuf_size) 139 { 140 struct compat_cmsghdr __user *ucmsg; 141 struct cmsghdr *kcmsg, *kcmsg_base; 142 compat_size_t ucmlen; 143 __kernel_size_t kcmlen, tmp; 144 int err = -EFAULT; 145 146 BUILD_BUG_ON(sizeof(struct compat_cmsghdr) != 147 CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr))); 148 149 kcmlen = 0; 150 kcmsg_base = kcmsg = (struct cmsghdr *)stackbuf; 151 ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg); 152 while (ucmsg != NULL) { 153 if (get_user(ucmlen, &ucmsg->cmsg_len)) 154 return -EFAULT; 155 156 /* Catch bogons. */ 157 if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg)) 158 return -EINVAL; 159 160 tmp = ((ucmlen - sizeof(*ucmsg)) + sizeof(struct cmsghdr)); 161 tmp = CMSG_ALIGN(tmp); 162 kcmlen += tmp; 163 ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen); 164 } 165 if (kcmlen == 0) 166 return -EINVAL; 167 168 /* The kcmlen holds the 64-bit version of the control length. 169 * It may not be modified as we do not stick it into the kmsg 170 * until we have successfully copied over all of the data 171 * from the user. 172 */ 173 if (kcmlen > stackbuf_size) 174 kcmsg_base = kcmsg = sock_kmalloc(sk, kcmlen, GFP_KERNEL); 175 if (kcmsg == NULL) 176 return -ENOMEM; 177 178 /* Now copy them over neatly. */ 179 memset(kcmsg, 0, kcmlen); 180 ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg); 181 while (ucmsg != NULL) { 182 struct compat_cmsghdr cmsg; 183 if (copy_from_user(&cmsg, ucmsg, sizeof(cmsg))) 184 goto Efault; 185 if (!CMSG_COMPAT_OK(cmsg.cmsg_len, ucmsg, kmsg)) 186 goto Einval; 187 tmp = ((cmsg.cmsg_len - sizeof(*ucmsg)) + sizeof(struct cmsghdr)); 188 if ((char *)kcmsg_base + kcmlen - (char *)kcmsg < CMSG_ALIGN(tmp)) 189 goto Einval; 190 kcmsg->cmsg_len = tmp; 191 kcmsg->cmsg_level = cmsg.cmsg_level; 192 kcmsg->cmsg_type = cmsg.cmsg_type; 193 tmp = CMSG_ALIGN(tmp); 194 if (copy_from_user(CMSG_DATA(kcmsg), 195 CMSG_COMPAT_DATA(ucmsg), 196 (cmsg.cmsg_len - sizeof(*ucmsg)))) 197 goto Efault; 198 199 /* Advance. */ 200 kcmsg = (struct cmsghdr *)((char *)kcmsg + tmp); 201 ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, cmsg.cmsg_len); 202 } 203 204 /* 205 * check the length of messages copied in is the same as the 206 * what we get from the first loop 207 */ 208 if ((char *)kcmsg - (char *)kcmsg_base != kcmlen) 209 goto Einval; 210 211 /* Ok, looks like we made it. Hook it up and return success. */ 212 kmsg->msg_control = kcmsg_base; 213 kmsg->msg_controllen = kcmlen; 214 return 0; 215 216 Einval: 217 err = -EINVAL; 218 Efault: 219 if (kcmsg_base != (struct cmsghdr *)stackbuf) 220 sock_kfree_s(sk, kcmsg_base, kcmlen); 221 return err; 222 } 223 224 int put_cmsg_compat(struct msghdr *kmsg, int level, int type, int len, void *data) 225 { 226 struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control; 227 struct compat_cmsghdr cmhdr; 228 struct old_timeval32 ctv; 229 struct old_timespec32 cts[3]; 230 int cmlen; 231 232 if (cm == NULL || kmsg->msg_controllen < sizeof(*cm)) { 233 kmsg->msg_flags |= MSG_CTRUNC; 234 return 0; /* XXX: return error? check spec. */ 235 } 236 237 if (!COMPAT_USE_64BIT_TIME) { 238 if (level == SOL_SOCKET && type == SO_TIMESTAMP_OLD) { 239 struct __kernel_old_timeval *tv = (struct __kernel_old_timeval *)data; 240 ctv.tv_sec = tv->tv_sec; 241 ctv.tv_usec = tv->tv_usec; 242 data = &ctv; 243 len = sizeof(ctv); 244 } 245 if (level == SOL_SOCKET && 246 (type == SO_TIMESTAMPNS_OLD || type == SO_TIMESTAMPING_OLD)) { 247 int count = type == SO_TIMESTAMPNS_OLD ? 1 : 3; 248 int i; 249 struct __kernel_old_timespec *ts = data; 250 for (i = 0; i < count; i++) { 251 cts[i].tv_sec = ts[i].tv_sec; 252 cts[i].tv_nsec = ts[i].tv_nsec; 253 } 254 data = &cts; 255 len = sizeof(cts[0]) * count; 256 } 257 } 258 259 cmlen = CMSG_COMPAT_LEN(len); 260 if (kmsg->msg_controllen < cmlen) { 261 kmsg->msg_flags |= MSG_CTRUNC; 262 cmlen = kmsg->msg_controllen; 263 } 264 cmhdr.cmsg_level = level; 265 cmhdr.cmsg_type = type; 266 cmhdr.cmsg_len = cmlen; 267 268 if (copy_to_user(cm, &cmhdr, sizeof cmhdr)) 269 return -EFAULT; 270 if (copy_to_user(CMSG_COMPAT_DATA(cm), data, cmlen - sizeof(struct compat_cmsghdr))) 271 return -EFAULT; 272 cmlen = CMSG_COMPAT_SPACE(len); 273 if (kmsg->msg_controllen < cmlen) 274 cmlen = kmsg->msg_controllen; 275 kmsg->msg_control += cmlen; 276 kmsg->msg_controllen -= cmlen; 277 return 0; 278 } 279 280 static int scm_max_fds_compat(struct msghdr *msg) 281 { 282 if (msg->msg_controllen <= sizeof(struct compat_cmsghdr)) 283 return 0; 284 return (msg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int); 285 } 286 287 void scm_detach_fds_compat(struct msghdr *msg, struct scm_cookie *scm) 288 { 289 struct compat_cmsghdr __user *cm = 290 (struct compat_cmsghdr __user *)msg->msg_control; 291 unsigned int o_flags = (msg->msg_flags & MSG_CMSG_CLOEXEC) ? O_CLOEXEC : 0; 292 int fdmax = min_t(int, scm_max_fds_compat(msg), scm->fp->count); 293 int __user *cmsg_data = CMSG_COMPAT_DATA(cm); 294 int err = 0, i; 295 296 for (i = 0; i < fdmax; i++) { 297 err = receive_fd_user(scm->fp->fp[i], cmsg_data + i, o_flags); 298 if (err < 0) 299 break; 300 } 301 302 if (i > 0) { 303 int cmlen = CMSG_COMPAT_LEN(i * sizeof(int)); 304 305 err = put_user(SOL_SOCKET, &cm->cmsg_level); 306 if (!err) 307 err = put_user(SCM_RIGHTS, &cm->cmsg_type); 308 if (!err) 309 err = put_user(cmlen, &cm->cmsg_len); 310 if (!err) { 311 cmlen = CMSG_COMPAT_SPACE(i * sizeof(int)); 312 if (msg->msg_controllen < cmlen) 313 cmlen = msg->msg_controllen; 314 msg->msg_control += cmlen; 315 msg->msg_controllen -= cmlen; 316 } 317 } 318 319 if (i < scm->fp->count || (scm->fp->count && fdmax <= 0)) 320 msg->msg_flags |= MSG_CTRUNC; 321 322 /* 323 * All of the files that fit in the message have had their usage counts 324 * incremented, so we just free the list. 325 */ 326 __scm_destroy(scm); 327 } 328 329 /* Argument list sizes for compat_sys_socketcall */ 330 #define AL(x) ((x) * sizeof(u32)) 331 static unsigned char nas[21] = { 332 AL(0), AL(3), AL(3), AL(3), AL(2), AL(3), 333 AL(3), AL(3), AL(4), AL(4), AL(4), AL(6), 334 AL(6), AL(2), AL(5), AL(5), AL(3), AL(3), 335 AL(4), AL(5), AL(4) 336 }; 337 #undef AL 338 339 static inline long __compat_sys_sendmsg(int fd, 340 struct compat_msghdr __user *msg, 341 unsigned int flags) 342 { 343 return __sys_sendmsg(fd, (struct user_msghdr __user *)msg, 344 flags | MSG_CMSG_COMPAT, false); 345 } 346 347 COMPAT_SYSCALL_DEFINE3(sendmsg, int, fd, struct compat_msghdr __user *, msg, 348 unsigned int, flags) 349 { 350 return __compat_sys_sendmsg(fd, msg, flags); 351 } 352 353 static inline long __compat_sys_sendmmsg(int fd, 354 struct compat_mmsghdr __user *mmsg, 355 unsigned int vlen, unsigned int flags) 356 { 357 return __sys_sendmmsg(fd, (struct mmsghdr __user *)mmsg, vlen, 358 flags | MSG_CMSG_COMPAT, false); 359 } 360 361 COMPAT_SYSCALL_DEFINE4(sendmmsg, int, fd, struct compat_mmsghdr __user *, mmsg, 362 unsigned int, vlen, unsigned int, flags) 363 { 364 return __compat_sys_sendmmsg(fd, mmsg, vlen, flags); 365 } 366 367 static inline long __compat_sys_recvmsg(int fd, 368 struct compat_msghdr __user *msg, 369 unsigned int flags) 370 { 371 return __sys_recvmsg(fd, (struct user_msghdr __user *)msg, 372 flags | MSG_CMSG_COMPAT, false); 373 } 374 375 COMPAT_SYSCALL_DEFINE3(recvmsg, int, fd, struct compat_msghdr __user *, msg, 376 unsigned int, flags) 377 { 378 return __compat_sys_recvmsg(fd, msg, flags); 379 } 380 381 static inline long __compat_sys_recvfrom(int fd, void __user *buf, 382 compat_size_t len, unsigned int flags, 383 struct sockaddr __user *addr, 384 int __user *addrlen) 385 { 386 return __sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr, 387 addrlen); 388 } 389 390 COMPAT_SYSCALL_DEFINE4(recv, int, fd, void __user *, buf, compat_size_t, len, unsigned int, flags) 391 { 392 return __compat_sys_recvfrom(fd, buf, len, flags, NULL, NULL); 393 } 394 395 COMPAT_SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, buf, compat_size_t, len, 396 unsigned int, flags, struct sockaddr __user *, addr, 397 int __user *, addrlen) 398 { 399 return __compat_sys_recvfrom(fd, buf, len, flags, addr, addrlen); 400 } 401 402 COMPAT_SYSCALL_DEFINE5(recvmmsg_time64, int, fd, struct compat_mmsghdr __user *, mmsg, 403 unsigned int, vlen, unsigned int, flags, 404 struct __kernel_timespec __user *, timeout) 405 { 406 return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen, 407 flags | MSG_CMSG_COMPAT, timeout, NULL); 408 } 409 410 #ifdef CONFIG_COMPAT_32BIT_TIME 411 COMPAT_SYSCALL_DEFINE5(recvmmsg_time32, int, fd, struct compat_mmsghdr __user *, mmsg, 412 unsigned int, vlen, unsigned int, flags, 413 struct old_timespec32 __user *, timeout) 414 { 415 return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen, 416 flags | MSG_CMSG_COMPAT, NULL, timeout); 417 } 418 #endif 419 420 COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args) 421 { 422 u32 a[AUDITSC_ARGS]; 423 unsigned int len; 424 u32 a0, a1; 425 int ret; 426 427 if (call < SYS_SOCKET || call > SYS_SENDMMSG) 428 return -EINVAL; 429 len = nas[call]; 430 if (len > sizeof(a)) 431 return -EINVAL; 432 433 if (copy_from_user(a, args, len)) 434 return -EFAULT; 435 436 ret = audit_socketcall_compat(len / sizeof(a[0]), a); 437 if (ret) 438 return ret; 439 440 a0 = a[0]; 441 a1 = a[1]; 442 443 switch (call) { 444 case SYS_SOCKET: 445 ret = __sys_socket(a0, a1, a[2]); 446 break; 447 case SYS_BIND: 448 ret = __sys_bind(a0, compat_ptr(a1), a[2]); 449 break; 450 case SYS_CONNECT: 451 ret = __sys_connect(a0, compat_ptr(a1), a[2]); 452 break; 453 case SYS_LISTEN: 454 ret = __sys_listen(a0, a1); 455 break; 456 case SYS_ACCEPT: 457 ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0); 458 break; 459 case SYS_GETSOCKNAME: 460 ret = __sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2])); 461 break; 462 case SYS_GETPEERNAME: 463 ret = __sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2])); 464 break; 465 case SYS_SOCKETPAIR: 466 ret = __sys_socketpair(a0, a1, a[2], compat_ptr(a[3])); 467 break; 468 case SYS_SEND: 469 ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3], NULL, 0); 470 break; 471 case SYS_SENDTO: 472 ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3], 473 compat_ptr(a[4]), a[5]); 474 break; 475 case SYS_RECV: 476 ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3], 477 NULL, NULL); 478 break; 479 case SYS_RECVFROM: 480 ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3], 481 compat_ptr(a[4]), 482 compat_ptr(a[5])); 483 break; 484 case SYS_SHUTDOWN: 485 ret = __sys_shutdown(a0, a1); 486 break; 487 case SYS_SETSOCKOPT: 488 ret = __sys_setsockopt(a0, a1, a[2], compat_ptr(a[3]), a[4]); 489 break; 490 case SYS_GETSOCKOPT: 491 ret = __sys_getsockopt(a0, a1, a[2], compat_ptr(a[3]), 492 compat_ptr(a[4])); 493 break; 494 case SYS_SENDMSG: 495 ret = __compat_sys_sendmsg(a0, compat_ptr(a1), a[2]); 496 break; 497 case SYS_SENDMMSG: 498 ret = __compat_sys_sendmmsg(a0, compat_ptr(a1), a[2], a[3]); 499 break; 500 case SYS_RECVMSG: 501 ret = __compat_sys_recvmsg(a0, compat_ptr(a1), a[2]); 502 break; 503 case SYS_RECVMMSG: 504 ret = __sys_recvmmsg(a0, compat_ptr(a1), a[2], 505 a[3] | MSG_CMSG_COMPAT, NULL, 506 compat_ptr(a[4])); 507 break; 508 case SYS_ACCEPT4: 509 ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]); 510 break; 511 default: 512 ret = -EINVAL; 513 break; 514 } 515 return ret; 516 } 517