net/compat.c

   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 void scm_detach_fds_compat(struct msghdr *kmsg, struct scm_cookie *scm)
 285 {
 286         struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
 287         int fdmax = (kmsg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int);
 288         int fdnum = scm->fp->count;
 289         struct file **fp = scm->fp->fp;
 290         int __user *cmfptr;
 291         int err = 0, i;
 292
 293         if (fdnum < fdmax)
 294                 fdmax = fdnum;
 295
 296         for (i = 0, cmfptr = (int __user *) CMSG_COMPAT_DATA(cm); i < fdmax; i++, cmfptr++) {
 297                 int new_fd;
 298                 err = security_file_receive(fp[i]);
 299                 if (err)
 300                         break;
 301                 err = get_unused_fd_flags(MSG_CMSG_CLOEXEC & kmsg->msg_flags
 302                                           ? O_CLOEXEC : 0);
 303                 if (err < 0)
 304                         break;
 305                 new_fd = err;
 306                 err = put_user(new_fd, cmfptr);
 307                 if (err) {
 308                         put_unused_fd(new_fd);
 309                         break;
 310                 }
 311                 /* Bump the usage count and install the file. */
 312                 __receive_sock(fp[i]);
 313                 fd_install(new_fd, get_file(fp[i]));
 314         }
 315
 316         if (i > 0) {
 317                 int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
 318                 err = put_user(SOL_SOCKET, &cm->cmsg_level);
 319                 if (!err)
 320                         err = put_user(SCM_RIGHTS, &cm->cmsg_type);
 321                 if (!err)
 322                         err = put_user(cmlen, &cm->cmsg_len);
 323                 if (!err) {
 324                         cmlen = CMSG_COMPAT_SPACE(i * sizeof(int));
 325                         kmsg->msg_control += cmlen;
 326                         kmsg->msg_controllen -= cmlen;
 327                 }
 328         }
 329         if (i < fdnum)
 330                 kmsg->msg_flags |= MSG_CTRUNC;
 331
 332         /*
 333          * All of the files that fit in the message have had their
 334          * usage counts incremented, so we just free the list.
 335          */
 336         __scm_destroy(scm);
 337 }
 338
 339 /* allocate a 64-bit sock_fprog on the user stack for duration of syscall. */
 340 struct sock_fprog __user *get_compat_bpf_fprog(char __user *optval)
 341 {
 342         struct compat_sock_fprog __user *fprog32 = (struct compat_sock_fprog __user *)optval;
 343         struct sock_fprog __user *kfprog = compat_alloc_user_space(sizeof(struct sock_fprog));
 344         struct compat_sock_fprog f32;
 345         struct sock_fprog f;
 346
 347         if (copy_from_user(&f32, fprog32, sizeof(*fprog32)))
 348                 return NULL;
 349         memset(&f, 0, sizeof(f));
 350         f.len = f32.len;
 351         f.filter = compat_ptr(f32.filter);
 352         if (copy_to_user(kfprog, &f, sizeof(struct sock_fprog)))
 353                 return NULL;
 354
 355         return kfprog;
 356 }
 357 EXPORT_SYMBOL_GPL(get_compat_bpf_fprog);
 358
 359 static int do_set_attach_filter(struct socket *sock, int level, int optname,
 360                                 char __user *optval, unsigned int optlen)
 361 {
 362         struct sock_fprog __user *kfprog;
 363
 364         kfprog = get_compat_bpf_fprog(optval);
 365         if (!kfprog)
 366                 return -EFAULT;
 367
 368         return sock_setsockopt(sock, level, optname, (char __user *)kfprog,
 369                               sizeof(struct sock_fprog));
 370 }
 371
 372 static int compat_sock_setsockopt(struct socket *sock, int level, int optname,
 373                                 char __user *optval, unsigned int optlen)
 374 {
 375         if (optname == SO_ATTACH_FILTER ||
 376             optname == SO_ATTACH_REUSEPORT_CBPF)
 377                 return do_set_attach_filter(sock, level, optname,
 378                                             optval, optlen);
 379         return sock_setsockopt(sock, level, optname, optval, optlen);
 380 }
 381
 382 static int __compat_sys_setsockopt(int fd, int level, int optname,
 383                                    char __user *optval, unsigned int optlen)
 384 {
 385         int err;
 386         struct socket *sock;
 387
 388         if (optlen > INT_MAX)
 389                 return -EINVAL;
 390
 391         sock = sockfd_lookup(fd, &err);
 392         if (sock) {
 393                 err = security_socket_setsockopt(sock, level, optname);
 394                 if (err) {
 395                         sockfd_put(sock);
 396                         return err;
 397                 }
 398
 399                 if (level == SOL_SOCKET)
 400                         err = compat_sock_setsockopt(sock, level,
 401                                         optname, optval, optlen);
 402                 else if (sock->ops->compat_setsockopt)
 403                         err = sock->ops->compat_setsockopt(sock, level,
 404                                         optname, optval, optlen);
 405                 else
 406                         err = sock->ops->setsockopt(sock, level,
 407                                         optname, optval, optlen);
 408                 sockfd_put(sock);
 409         }
 410         return err;
 411 }
 412
 413 COMPAT_SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
 414                        char __user *, optval, unsigned int, optlen)
 415 {
 416         return __compat_sys_setsockopt(fd, level, optname, optval, optlen);
 417 }
 418
 419 static int __compat_sys_getsockopt(int fd, int level, int optname,
 420                                    char __user *optval,
 421                                    int __user *optlen)
 422 {
 423         int err;
 424         struct socket *sock = sockfd_lookup(fd, &err);
 425
 426         if (sock) {
 427                 err = security_socket_getsockopt(sock, level, optname);
 428                 if (err) {
 429                         sockfd_put(sock);
 430                         return err;
 431                 }
 432
 433                 if (level == SOL_SOCKET)
 434                         err = sock_getsockopt(sock, level,
 435                                         optname, optval, optlen);
 436                 else if (sock->ops->compat_getsockopt)
 437                         err = sock->ops->compat_getsockopt(sock, level,
 438                                         optname, optval, optlen);
 439                 else
 440                         err = sock->ops->getsockopt(sock, level,
 441                                         optname, optval, optlen);
 442                 sockfd_put(sock);
 443         }
 444         return err;
 445 }
 446
 447 COMPAT_SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname,
 448                        char __user *, optval, int __user *, optlen)
 449 {
 450         return __compat_sys_getsockopt(fd, level, optname, optval, optlen);
 451 }
 452
 453 /* Argument list sizes for compat_sys_socketcall */
 454 #define AL(x) ((x) * sizeof(u32))
 455 static unsigned char nas[21] = {
 456         AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
 457         AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
 458         AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
 459         AL(4), AL(5), AL(4)
 460 };
 461 #undef AL
 462
 463 static inline long __compat_sys_sendmsg(int fd,
 464                                         struct compat_msghdr __user *msg,
 465                                         unsigned int flags)
 466 {
 467         return __sys_sendmsg(fd, (struct user_msghdr __user *)msg,
 468                              flags | MSG_CMSG_COMPAT, false);
 469 }
 470
 471 COMPAT_SYSCALL_DEFINE3(sendmsg, int, fd, struct compat_msghdr __user *, msg,
 472                        unsigned int, flags)
 473 {
 474         return __compat_sys_sendmsg(fd, msg, flags);
 475 }
 476
 477 static inline long __compat_sys_sendmmsg(int fd,
 478                                          struct compat_mmsghdr __user *mmsg,
 479                                          unsigned int vlen, unsigned int flags)
 480 {
 481         return __sys_sendmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
 482                               flags | MSG_CMSG_COMPAT, false);
 483 }
 484
 485 COMPAT_SYSCALL_DEFINE4(sendmmsg, int, fd, struct compat_mmsghdr __user *, mmsg,
 486                        unsigned int, vlen, unsigned int, flags)
 487 {
 488         return __compat_sys_sendmmsg(fd, mmsg, vlen, flags);
 489 }
 490
 491 static inline long __compat_sys_recvmsg(int fd,
 492                                         struct compat_msghdr __user *msg,
 493                                         unsigned int flags)
 494 {
 495         return __sys_recvmsg(fd, (struct user_msghdr __user *)msg,
 496                              flags | MSG_CMSG_COMPAT, false);
 497 }
 498
 499 COMPAT_SYSCALL_DEFINE3(recvmsg, int, fd, struct compat_msghdr __user *, msg,
 500                        unsigned int, flags)
 501 {
 502         return __compat_sys_recvmsg(fd, msg, flags);
 503 }
 504
 505 static inline long __compat_sys_recvfrom(int fd, void __user *buf,
 506                                          compat_size_t len, unsigned int flags,
 507                                          struct sockaddr __user *addr,
 508                                          int __user *addrlen)
 509 {
 510         return __sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr,
 511                               addrlen);
 512 }
 513
 514 COMPAT_SYSCALL_DEFINE4(recv, int, fd, void __user *, buf, compat_size_t, len, unsigned int, flags)
 515 {
 516         return __compat_sys_recvfrom(fd, buf, len, flags, NULL, NULL);
 517 }
 518
 519 COMPAT_SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, buf, compat_size_t, len,
 520                        unsigned int, flags, struct sockaddr __user *, addr,
 521                        int __user *, addrlen)
 522 {
 523         return __compat_sys_recvfrom(fd, buf, len, flags, addr, addrlen);
 524 }
 525
 526 COMPAT_SYSCALL_DEFINE5(recvmmsg_time64, int, fd, struct compat_mmsghdr __user *, mmsg,
 527                        unsigned int, vlen, unsigned int, flags,
 528                        struct __kernel_timespec __user *, timeout)
 529 {
 530         return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
 531                               flags | MSG_CMSG_COMPAT, timeout, NULL);
 532 }
 533
 534 #ifdef CONFIG_COMPAT_32BIT_TIME
 535 COMPAT_SYSCALL_DEFINE5(recvmmsg_time32, int, fd, struct compat_mmsghdr __user *, mmsg,
 536                        unsigned int, vlen, unsigned int, flags,
 537                        struct old_timespec32 __user *, timeout)
 538 {
 539         return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
 540                               flags | MSG_CMSG_COMPAT, NULL, timeout);
 541 }
 542 #endif
 543
 544 COMPAT_SYSCALL_DEFINE2(socketcall, int, call, u32 __user *, args)
 545 {
 546         u32 a[AUDITSC_ARGS];
 547         unsigned int len;
 548         u32 a0, a1;
 549         int ret;
 550
 551         if (call < SYS_SOCKET || call > SYS_SENDMMSG)
 552                 return -EINVAL;
 553         len = nas[call];
 554         if (len > sizeof(a))
 555                 return -EINVAL;
 556
 557         if (copy_from_user(a, args, len))
 558                 return -EFAULT;
 559
 560         ret = audit_socketcall_compat(len / sizeof(a[0]), a);
 561         if (ret)
 562                 return ret;
 563
 564         a0 = a[0];
 565         a1 = a[1];
 566
 567         switch (call) {
 568         case SYS_SOCKET:
 569                 ret = __sys_socket(a0, a1, a[2]);
 570                 break;
 571         case SYS_BIND:
 572                 ret = __sys_bind(a0, compat_ptr(a1), a[2]);
 573                 break;
 574         case SYS_CONNECT:
 575                 ret = __sys_connect(a0, compat_ptr(a1), a[2]);
 576                 break;
 577         case SYS_LISTEN:
 578                 ret = __sys_listen(a0, a1);
 579                 break;
 580         case SYS_ACCEPT:
 581                 ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), 0);
 582                 break;
 583         case SYS_GETSOCKNAME:
 584                 ret = __sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]));
 585                 break;
 586         case SYS_GETPEERNAME:
 587                 ret = __sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2]));
 588                 break;
 589         case SYS_SOCKETPAIR:
 590                 ret = __sys_socketpair(a0, a1, a[2], compat_ptr(a[3]));
 591                 break;
 592         case SYS_SEND:
 593                 ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3], NULL, 0);
 594                 break;
 595         case SYS_SENDTO:
 596                 ret = __sys_sendto(a0, compat_ptr(a1), a[2], a[3],
 597                                    compat_ptr(a[4]), a[5]);
 598                 break;
 599         case SYS_RECV:
 600                 ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
 601                                             NULL, NULL);
 602                 break;
 603         case SYS_RECVFROM:
 604                 ret = __compat_sys_recvfrom(a0, compat_ptr(a1), a[2], a[3],
 605                                             compat_ptr(a[4]),
 606                                             compat_ptr(a[5]));
 607                 break;
 608         case SYS_SHUTDOWN:
 609                 ret = __sys_shutdown(a0, a1);
 610                 break;
 611         case SYS_SETSOCKOPT:
 612                 ret = __compat_sys_setsockopt(a0, a1, a[2],
 613                                               compat_ptr(a[3]), a[4]);
 614                 break;
 615         case SYS_GETSOCKOPT:
 616                 ret = __compat_sys_getsockopt(a0, a1, a[2],
 617                                               compat_ptr(a[3]),
 618                                               compat_ptr(a[4]));
 619                 break;
 620         case SYS_SENDMSG:
 621                 ret = __compat_sys_sendmsg(a0, compat_ptr(a1), a[2]);
 622                 break;
 623         case SYS_SENDMMSG:
 624                 ret = __compat_sys_sendmmsg(a0, compat_ptr(a1), a[2], a[3]);
 625                 break;
 626         case SYS_RECVMSG:
 627                 ret = __compat_sys_recvmsg(a0, compat_ptr(a1), a[2]);
 628                 break;
 629         case SYS_RECVMMSG:
 630                 ret = __sys_recvmmsg(a0, compat_ptr(a1), a[2],
 631                                      a[3] | MSG_CMSG_COMPAT, NULL,
 632                                      compat_ptr(a[4]));
 633                 break;
 634         case SYS_ACCEPT4:
 635                 ret = __sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]);
 636                 break;
 637         default:
 638                 ret = -EINVAL;
 639                 break;
 640         }
 641         return ret;
 642 }