net/compat.c

   1 /*
   2  * 32bit Socket syscall emulation. Based on arch/sparc64/kernel/sys_sparc32.c.
   3  *
   4  * Copyright (C) 2000           VA Linux Co
   5  * Copyright (C) 2000           Don Dugger <n0ano@valinux.com>
   6  * Copyright (C) 1999           Arun Sharma <arun.sharma@intel.com>
   7  * Copyright (C) 1997,1998      Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   8  * Copyright (C) 1997           David S. Miller (davem@caip.rutgers.edu)
   9  * Copyright (C) 2000           Hewlett-Packard Co.
  10  * Copyright (C) 2000           David Mosberger-Tang <davidm@hpl.hp.com>
  11  * Copyright (C) 2000,2001      Andi Kleen, SuSE Labs
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/fs.h>
  16 #include <linux/sched.h>
  17 #include <linux/types.h>
  18 #include <linux/file.h>
  19 #include <linux/icmpv6.h>
  20 #include <linux/socket.h>
  21 #include <linux/syscalls.h>
  22 #include <linux/filter.h>
  23 #include <linux/compat.h>
  24 #include <linux/netfilter_ipv4/ip_tables.h>
  25 #include <linux/security.h>
  26
  27 #include <net/scm.h>
  28 #include <net/sock.h>
  29 #include <asm/uaccess.h>
  30 #include <net/compat.h>
  31
  32 static inline int iov_from_user_compat_to_kern(struct iovec *kiov,
  33                                           struct compat_iovec __user *uiov32,
  34                                           int niov)
  35 {
  36         int tot_len = 0;
  37
  38         while(niov > 0) {
  39                 compat_uptr_t buf;
  40                 compat_size_t len;
  41
  42                 if(get_user(len, &uiov32->iov_len) ||
  43                    get_user(buf, &uiov32->iov_base)) {
  44                         tot_len = -EFAULT;
  45                         break;
  46                 }
  47                 tot_len += len;
  48                 kiov->iov_base = compat_ptr(buf);
  49                 kiov->iov_len = (__kernel_size_t) len;
  50                 uiov32++;
  51                 kiov++;
  52                 niov--;
  53         }
  54         return tot_len;
  55 }
  56
  57 int get_compat_msghdr(struct msghdr *kmsg, struct compat_msghdr __user *umsg)
  58 {
  59         compat_uptr_t tmp1, tmp2, tmp3;
  60
  61         if (!access_ok(VERIFY_READ, umsg, sizeof(*umsg)) ||
  62             __get_user(tmp1, &umsg->msg_name) ||
  63             __get_user(kmsg->msg_namelen, &umsg->msg_namelen) ||
  64             __get_user(tmp2, &umsg->msg_iov) ||
  65             __get_user(kmsg->msg_iovlen, &umsg->msg_iovlen) ||
  66             __get_user(tmp3, &umsg->msg_control) ||
  67             __get_user(kmsg->msg_controllen, &umsg->msg_controllen) ||
  68             __get_user(kmsg->msg_flags, &umsg->msg_flags))
  69                 return -EFAULT;
  70         kmsg->msg_name = compat_ptr(tmp1);
  71         kmsg->msg_iov = compat_ptr(tmp2);
  72         kmsg->msg_control = compat_ptr(tmp3);
  73         return 0;
  74 }
  75
  76 /* I've named the args so it is easy to tell whose space the pointers are in. */
  77 int verify_compat_iovec(struct msghdr *kern_msg, struct iovec *kern_iov,
  78                    char *kern_address, int mode)
  79 {
  80         int tot_len;
  81
  82         if(kern_msg->msg_namelen) {
  83                 if(mode==VERIFY_READ) {
  84                         int err = move_addr_to_kernel(kern_msg->msg_name,
  85                                                       kern_msg->msg_namelen,
  86                                                       kern_address);
  87                         if(err < 0)
  88                                 return err;
  89                 }
  90                 kern_msg->msg_name = kern_address;
  91         } else
  92                 kern_msg->msg_name = NULL;
  93
  94         tot_len = iov_from_user_compat_to_kern(kern_iov,
  95                                           (struct compat_iovec __user *)kern_msg->msg_iov,
  96                                           kern_msg->msg_iovlen);
  97         if(tot_len >= 0)
  98                 kern_msg->msg_iov = kern_iov;
  99
 100         return tot_len;
 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) + CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr))))
 108 #define CMSG_COMPAT_SPACE(len)                          \
 109         (CMSG_COMPAT_ALIGN(sizeof(struct compat_cmsghdr)) + CMSG_COMPAT_ALIGN(len))
 110 #define CMSG_COMPAT_LEN(len)                            \
 111         (CMSG_COMPAT_ALIGN(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 *)(ucmsg) - (char *)(mhdr)->msg_control)))
 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         kcmlen = 0;
 148         kcmsg_base = kcmsg = (struct cmsghdr *)stackbuf;
 149         ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
 150         while(ucmsg != NULL) {
 151                 if(get_user(ucmlen, &ucmsg->cmsg_len))
 152                         return -EFAULT;
 153
 154                 /* Catch bogons. */
 155                 if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
 156                         return -EINVAL;
 157
 158                 tmp = ((ucmlen - CMSG_COMPAT_ALIGN(sizeof(*ucmsg))) +
 159                        CMSG_ALIGN(sizeof(struct cmsghdr)));
 160                 tmp = CMSG_ALIGN(tmp);
 161                 kcmlen += tmp;
 162                 ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
 163         }
 164         if(kcmlen == 0)
 165                 return -EINVAL;
 166
 167         /* The kcmlen holds the 64-bit version of the control length.
 168          * It may not be modified as we do not stick it into the kmsg
 169          * until we have successfully copied over all of the data
 170          * from the user.
 171          */
 172         if (kcmlen > stackbuf_size)
 173                 kcmsg_base = kcmsg = sock_kmalloc(sk, kcmlen, GFP_KERNEL);
 174         if (kcmsg == NULL)
 175                 return -ENOBUFS;
 176
 177         /* Now copy them over neatly. */
 178         memset(kcmsg, 0, kcmlen);
 179         ucmsg = CMSG_COMPAT_FIRSTHDR(kmsg);
 180         while(ucmsg != NULL) {
 181                 if (__get_user(ucmlen, &ucmsg->cmsg_len))
 182                         goto Efault;
 183                 if (!CMSG_COMPAT_OK(ucmlen, ucmsg, kmsg))
 184                         goto Einval;
 185                 tmp = ((ucmlen - CMSG_COMPAT_ALIGN(sizeof(*ucmsg))) +
 186                        CMSG_ALIGN(sizeof(struct cmsghdr)));
 187                 if ((char *)kcmsg_base + kcmlen - (char *)kcmsg < CMSG_ALIGN(tmp))
 188                         goto Einval;
 189                 kcmsg->cmsg_len = tmp;
 190                 tmp = CMSG_ALIGN(tmp);
 191                 if (__get_user(kcmsg->cmsg_level, &ucmsg->cmsg_level) ||
 192                     __get_user(kcmsg->cmsg_type, &ucmsg->cmsg_type) ||
 193                     copy_from_user(CMSG_DATA(kcmsg),
 194                                    CMSG_COMPAT_DATA(ucmsg),
 195                                    (ucmlen - CMSG_COMPAT_ALIGN(sizeof(*ucmsg)))))
 196                         goto Efault;
 197
 198                 /* Advance. */
 199                 kcmsg = (struct cmsghdr *)((char *)kcmsg + tmp);
 200                 ucmsg = cmsg_compat_nxthdr(kmsg, ucmsg, ucmlen);
 201         }
 202
 203         /* Ok, looks like we made it.  Hook it up and return success. */
 204         kmsg->msg_control = kcmsg_base;
 205         kmsg->msg_controllen = kcmlen;
 206         return 0;
 207
 208 Einval:
 209         err = -EINVAL;
 210 Efault:
 211         if (kcmsg_base != (struct cmsghdr *)stackbuf)
 212                 sock_kfree_s(sk, kcmsg_base, kcmlen);
 213         return err;
 214 }
 215
 216 int put_cmsg_compat(struct msghdr *kmsg, int level, int type, int len, void *data)
 217 {
 218         struct compat_timeval ctv;
 219         struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
 220         struct compat_cmsghdr cmhdr;
 221         int cmlen;
 222
 223         if(cm == NULL || kmsg->msg_controllen < sizeof(*cm)) {
 224                 kmsg->msg_flags |= MSG_CTRUNC;
 225                 return 0; /* XXX: return error? check spec. */
 226         }
 227
 228         if (level == SOL_SOCKET && type == SO_TIMESTAMP) {
 229                 struct timeval *tv = (struct timeval *)data;
 230                 ctv.tv_sec = tv->tv_sec;
 231                 ctv.tv_usec = tv->tv_usec;
 232                 data = &ctv;
 233                 len = sizeof(struct compat_timeval);
 234         }
 235
 236         cmlen = CMSG_COMPAT_LEN(len);
 237         if(kmsg->msg_controllen < cmlen) {
 238                 kmsg->msg_flags |= MSG_CTRUNC;
 239                 cmlen = kmsg->msg_controllen;
 240         }
 241         cmhdr.cmsg_level = level;
 242         cmhdr.cmsg_type = type;
 243         cmhdr.cmsg_len = cmlen;
 244
 245         if(copy_to_user(cm, &cmhdr, sizeof cmhdr))
 246                 return -EFAULT;
 247         if(copy_to_user(CMSG_COMPAT_DATA(cm), data, cmlen - sizeof(struct compat_cmsghdr)))
 248                 return -EFAULT;
 249         cmlen = CMSG_COMPAT_SPACE(len);
 250         kmsg->msg_control += cmlen;
 251         kmsg->msg_controllen -= cmlen;
 252         return 0;
 253 }
 254
 255 void scm_detach_fds_compat(struct msghdr *kmsg, struct scm_cookie *scm)
 256 {
 257         struct compat_cmsghdr __user *cm = (struct compat_cmsghdr __user *) kmsg->msg_control;
 258         int fdmax = (kmsg->msg_controllen - sizeof(struct compat_cmsghdr)) / sizeof(int);
 259         int fdnum = scm->fp->count;
 260         struct file **fp = scm->fp->fp;
 261         int __user *cmfptr;
 262         int err = 0, i;
 263
 264         if (fdnum < fdmax)
 265                 fdmax = fdnum;
 266
 267         for (i = 0, cmfptr = (int __user *) CMSG_COMPAT_DATA(cm); i < fdmax; i++, cmfptr++) {
 268                 int new_fd;
 269                 err = security_file_receive(fp[i]);
 270                 if (err)
 271                         break;
 272                 err = get_unused_fd();
 273                 if (err < 0)
 274                         break;
 275                 new_fd = err;
 276                 err = put_user(new_fd, cmfptr);
 277                 if (err) {
 278                         put_unused_fd(new_fd);
 279                         break;
 280                 }
 281                 /* Bump the usage count and install the file. */
 282                 get_file(fp[i]);
 283                 fd_install(new_fd, fp[i]);
 284         }
 285
 286         if (i > 0) {
 287                 int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
 288                 err = put_user(SOL_SOCKET, &cm->cmsg_level);
 289                 if (!err)
 290                         err = put_user(SCM_RIGHTS, &cm->cmsg_type);
 291                 if (!err)
 292                         err = put_user(cmlen, &cm->cmsg_len);
 293                 if (!err) {
 294                         cmlen = CMSG_COMPAT_SPACE(i * sizeof(int));
 295                         kmsg->msg_control += cmlen;
 296                         kmsg->msg_controllen -= cmlen;
 297                 }
 298         }
 299         if (i < fdnum)
 300                 kmsg->msg_flags |= MSG_CTRUNC;
 301
 302         /*
 303          * All of the files that fit in the message have had their
 304          * usage counts incremented, so we just free the list.
 305          */
 306         __scm_destroy(scm);
 307 }
 308
 309 /*
 310  * For now, we assume that the compatibility and native version
 311  * of struct ipt_entry are the same - sfr.  FIXME
 312  */
 313 struct compat_ipt_replace {
 314         char                    name[IPT_TABLE_MAXNAMELEN];
 315         u32                     valid_hooks;
 316         u32                     num_entries;
 317         u32                     size;
 318         u32                     hook_entry[NF_IP_NUMHOOKS];
 319         u32                     underflow[NF_IP_NUMHOOKS];
 320         u32                     num_counters;
 321         compat_uptr_t           counters;       /* struct ipt_counters * */
 322         struct ipt_entry        entries[0];
 323 };
 324
 325 static int do_netfilter_replace(int fd, int level, int optname,
 326                                 char __user *optval, int optlen)
 327 {
 328         struct compat_ipt_replace __user *urepl;
 329         struct ipt_replace __user *repl_nat;
 330         char name[IPT_TABLE_MAXNAMELEN];
 331         u32 origsize, tmp32, num_counters;
 332         unsigned int repl_nat_size;
 333         int ret;
 334         int i;
 335         compat_uptr_t ucntrs;
 336
 337         urepl = (struct compat_ipt_replace __user *)optval;
 338         if (get_user(origsize, &urepl->size))
 339                 return -EFAULT;
 340
 341         /* Hack: Causes ipchains to give correct error msg --RR */
 342         if (optlen != sizeof(*urepl) + origsize)
 343                 return -ENOPROTOOPT;
 344
 345         /* XXX Assumes that size of ipt_entry is the same both in
 346          *     native and compat environments.
 347          */
 348         repl_nat_size = sizeof(*repl_nat) + origsize;
 349         repl_nat = compat_alloc_user_space(repl_nat_size);
 350
 351         ret = -EFAULT;
 352         if (put_user(origsize, &repl_nat->size))
 353                 goto out;
 354
 355         if (!access_ok(VERIFY_READ, urepl, optlen) ||
 356             !access_ok(VERIFY_WRITE, repl_nat, optlen))
 357                 goto out;
 358
 359         if (__copy_from_user(name, urepl->name, sizeof(urepl->name)) ||
 360             __copy_to_user(repl_nat->name, name, sizeof(repl_nat->name)))
 361                 goto out;
 362
 363         if (__get_user(tmp32, &urepl->valid_hooks) ||
 364             __put_user(tmp32, &repl_nat->valid_hooks))
 365                 goto out;
 366
 367         if (__get_user(tmp32, &urepl->num_entries) ||
 368             __put_user(tmp32, &repl_nat->num_entries))
 369                 goto out;
 370
 371         if (__get_user(num_counters, &urepl->num_counters) ||
 372             __put_user(num_counters, &repl_nat->num_counters))
 373                 goto out;
 374
 375         if (__get_user(ucntrs, &urepl->counters) ||
 376             __put_user(compat_ptr(ucntrs), &repl_nat->counters))
 377                 goto out;
 378
 379         if (__copy_in_user(&repl_nat->entries[0],
 380                            &urepl->entries[0],
 381                            origsize))
 382                 goto out;
 383
 384         for (i = 0; i < NF_IP_NUMHOOKS; i++) {
 385                 if (__get_user(tmp32, &urepl->hook_entry[i]) ||
 386                     __put_user(tmp32, &repl_nat->hook_entry[i]) ||
 387                     __get_user(tmp32, &urepl->underflow[i]) ||
 388                     __put_user(tmp32, &repl_nat->underflow[i]))
 389                         goto out;
 390         }
 391
 392         /*
 393          * Since struct ipt_counters just contains two u_int64_t members
 394          * we can just do the access_ok check here and pass the (converted)
 395          * pointer into the standard syscall.  We hope that the pointer is
 396          * not misaligned ...
 397          */
 398         if (!access_ok(VERIFY_WRITE, compat_ptr(ucntrs),
 399                        num_counters * sizeof(struct ipt_counters)))
 400                 goto out;
 401
 402
 403         ret = sys_setsockopt(fd, level, optname,
 404                              (char __user *)repl_nat, repl_nat_size);
 405
 406 out:
 407         return ret;
 408 }
 409
 410 /*
 411  * A struct sock_filter is architecture independent.
 412  */
 413 struct compat_sock_fprog {
 414         u16             len;
 415         compat_uptr_t   filter;         /* struct sock_filter * */
 416 };
 417
 418 static int do_set_attach_filter(struct socket *sock, int level, int optname,
 419                                 char __user *optval, int optlen)
 420 {
 421         struct compat_sock_fprog __user *fprog32 = (struct compat_sock_fprog __user *)optval;
 422         struct sock_fprog __user *kfprog = compat_alloc_user_space(sizeof(struct sock_fprog));
 423         compat_uptr_t ptr;
 424         u16 len;
 425
 426         if (!access_ok(VERIFY_READ, fprog32, sizeof(*fprog32)) ||
 427             !access_ok(VERIFY_WRITE, kfprog, sizeof(struct sock_fprog)) ||
 428             __get_user(len, &fprog32->len) ||
 429             __get_user(ptr, &fprog32->filter) ||
 430             __put_user(len, &kfprog->len) ||
 431             __put_user(compat_ptr(ptr), &kfprog->filter))
 432                 return -EFAULT;
 433
 434         return sock_setsockopt(sock, level, optname, (char __user *)kfprog,
 435                               sizeof(struct sock_fprog));
 436 }
 437
 438 static int do_set_sock_timeout(struct socket *sock, int level,
 439                 int optname, char __user *optval, int optlen)
 440 {
 441         struct compat_timeval __user *up = (struct compat_timeval __user *) optval;
 442         struct timeval ktime;
 443         mm_segment_t old_fs;
 444         int err;
 445
 446         if (optlen < sizeof(*up))
 447                 return -EINVAL;
 448         if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
 449             __get_user(ktime.tv_sec, &up->tv_sec) ||
 450             __get_user(ktime.tv_usec, &up->tv_usec))
 451                 return -EFAULT;
 452         old_fs = get_fs();
 453         set_fs(KERNEL_DS);
 454         err = sock_setsockopt(sock, level, optname, (char *) &ktime, sizeof(ktime));
 455         set_fs(old_fs);
 456
 457         return err;
 458 }
 459
 460 static int compat_sock_setsockopt(struct socket *sock, int level, int optname,
 461                                 char __user *optval, int optlen)
 462 {
 463         if (optname == SO_ATTACH_FILTER)
 464                 return do_set_attach_filter(sock, level, optname,
 465                                             optval, optlen);
 466         if (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO)
 467                 return do_set_sock_timeout(sock, level, optname, optval, optlen);
 468
 469         return sock_setsockopt(sock, level, optname, optval, optlen);
 470 }
 471
 472 asmlinkage long compat_sys_setsockopt(int fd, int level, int optname,
 473                                 char __user *optval, int optlen)
 474 {
 475         int err;
 476         struct socket *sock;
 477
 478         if (level == SOL_IPV6 && optname == IPT_SO_SET_REPLACE)
 479                 return do_netfilter_replace(fd, level, optname,
 480                                             optval, optlen);
 481
 482         if (optlen < 0)
 483                 return -EINVAL;
 484
 485         if ((sock = sockfd_lookup(fd, &err))!=NULL)
 486         {
 487                 err = security_socket_setsockopt(sock,level,optname);
 488                 if (err) {
 489                         sockfd_put(sock);
 490                         return err;
 491                 }
 492
 493                 if (level == SOL_SOCKET)
 494                         err = compat_sock_setsockopt(sock, level,
 495                                         optname, optval, optlen);
 496                 else if (sock->ops->compat_setsockopt)
 497                         err = sock->ops->compat_setsockopt(sock, level,
 498                                         optname, optval, optlen);
 499                 else
 500                         err = sock->ops->setsockopt(sock, level,
 501                                         optname, optval, optlen);
 502                 sockfd_put(sock);
 503         }
 504         return err;
 505 }
 506
 507 static int do_get_sock_timeout(struct socket *sock, int level, int optname,
 508                 char __user *optval, int __user *optlen)
 509 {
 510         struct compat_timeval __user *up;
 511         struct timeval ktime;
 512         mm_segment_t old_fs;
 513         int len, err;
 514
 515         up = (struct compat_timeval __user *) optval;
 516         if (get_user(len, optlen))
 517                 return -EFAULT;
 518         if (len < sizeof(*up))
 519                 return -EINVAL;
 520         len = sizeof(ktime);
 521         old_fs = get_fs();
 522         set_fs(KERNEL_DS);
 523         err = sock_getsockopt(sock, level, optname, (char *) &ktime, &len);
 524         set_fs(old_fs);
 525
 526         if (!err) {
 527                 if (put_user(sizeof(*up), optlen) ||
 528                     !access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
 529                     __put_user(ktime.tv_sec, &up->tv_sec) ||
 530                     __put_user(ktime.tv_usec, &up->tv_usec))
 531                         err = -EFAULT;
 532         }
 533         return err;
 534 }
 535
 536 static int compat_sock_getsockopt(struct socket *sock, int level, int optname,
 537                                 char __user *optval, int __user *optlen)
 538 {
 539         if (optname == SO_RCVTIMEO || optname == SO_SNDTIMEO)
 540                 return do_get_sock_timeout(sock, level, optname, optval, optlen);
 541         return sock_getsockopt(sock, level, optname, optval, optlen);
 542 }
 543
 544 int compat_sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
 545 {
 546         struct compat_timeval __user *ctv =
 547                         (struct compat_timeval __user*) userstamp;
 548         int err = -ENOENT;
 549
 550         if (!sock_flag(sk, SOCK_TIMESTAMP))
 551                 sock_enable_timestamp(sk);
 552         if (sk->sk_stamp.tv_sec == -1)
 553                 return err;
 554         if (sk->sk_stamp.tv_sec == 0)
 555                 do_gettimeofday(&sk->sk_stamp);
 556         if (put_user(sk->sk_stamp.tv_sec, &ctv->tv_sec) ||
 557                         put_user(sk->sk_stamp.tv_usec, &ctv->tv_usec))
 558                 err = -EFAULT;
 559         return err;
 560 }
 561 EXPORT_SYMBOL(compat_sock_get_timestamp);
 562
 563 asmlinkage long compat_sys_getsockopt(int fd, int level, int optname,
 564                                 char __user *optval, int __user *optlen)
 565 {
 566         int err;
 567         struct socket *sock;
 568
 569         if ((sock = sockfd_lookup(fd, &err))!=NULL)
 570         {
 571                 err = security_socket_getsockopt(sock, level,
 572                                                            optname);
 573                 if (err) {
 574                         sockfd_put(sock);
 575                         return err;
 576                 }
 577
 578                 if (level == SOL_SOCKET)
 579                         err = compat_sock_getsockopt(sock, level,
 580                                         optname, optval, optlen);
 581                 else if (sock->ops->compat_getsockopt)
 582                         err = sock->ops->compat_getsockopt(sock, level,
 583                                         optname, optval, optlen);
 584                 else
 585                         err = sock->ops->getsockopt(sock, level,
 586                                         optname, optval, optlen);
 587                 sockfd_put(sock);
 588         }
 589         return err;
 590 }
 591 /* Argument list sizes for compat_sys_socketcall */
 592 #define AL(x) ((x) * sizeof(u32))
 593 static unsigned char nas[18]={AL(0),AL(3),AL(3),AL(3),AL(2),AL(3),
 594                                 AL(3),AL(3),AL(4),AL(4),AL(4),AL(6),
 595                                 AL(6),AL(2),AL(5),AL(5),AL(3),AL(3)};
 596 #undef AL
 597
 598 asmlinkage long compat_sys_sendmsg(int fd, struct compat_msghdr __user *msg, unsigned flags)
 599 {
 600         return sys_sendmsg(fd, (struct msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
 601 }
 602
 603 asmlinkage long compat_sys_recvmsg(int fd, struct compat_msghdr __user *msg, unsigned int flags)
 604 {
 605         return sys_recvmsg(fd, (struct msghdr __user *)msg, flags | MSG_CMSG_COMPAT);
 606 }
 607
 608 asmlinkage long compat_sys_socketcall(int call, u32 __user *args)
 609 {
 610         int ret;
 611         u32 a[6];
 612         u32 a0, a1;
 613
 614         if (call < SYS_SOCKET || call > SYS_RECVMSG)
 615                 return -EINVAL;
 616         if (copy_from_user(a, args, nas[call]))
 617                 return -EFAULT;
 618         a0 = a[0];
 619         a1 = a[1];
 620
 621         switch(call) {
 622         case SYS_SOCKET:
 623                 ret = sys_socket(a0, a1, a[2]);
 624                 break;
 625         case SYS_BIND:
 626                 ret = sys_bind(a0, compat_ptr(a1), a[2]);
 627                 break;
 628         case SYS_CONNECT:
 629                 ret = sys_connect(a0, compat_ptr(a1), a[2]);
 630                 break;
 631         case SYS_LISTEN:
 632                 ret = sys_listen(a0, a1);
 633                 break;
 634         case SYS_ACCEPT:
 635                 ret = sys_accept(a0, compat_ptr(a1), compat_ptr(a[2]));
 636                 break;
 637         case SYS_GETSOCKNAME:
 638                 ret = sys_getsockname(a0, compat_ptr(a1), compat_ptr(a[2]));
 639                 break;
 640         case SYS_GETPEERNAME:
 641                 ret = sys_getpeername(a0, compat_ptr(a1), compat_ptr(a[2]));
 642                 break;
 643         case SYS_SOCKETPAIR:
 644                 ret = sys_socketpair(a0, a1, a[2], compat_ptr(a[3]));
 645                 break;
 646         case SYS_SEND:
 647                 ret = sys_send(a0, compat_ptr(a1), a[2], a[3]);
 648                 break;
 649         case SYS_SENDTO:
 650                 ret = sys_sendto(a0, compat_ptr(a1), a[2], a[3], compat_ptr(a[4]), a[5]);
 651                 break;
 652         case SYS_RECV:
 653                 ret = sys_recv(a0, compat_ptr(a1), a[2], a[3]);
 654                 break;
 655         case SYS_RECVFROM:
 656                 ret = sys_recvfrom(a0, compat_ptr(a1), a[2], a[3], compat_ptr(a[4]), compat_ptr(a[5]));
 657                 break;
 658         case SYS_SHUTDOWN:
 659                 ret = sys_shutdown(a0,a1);
 660                 break;
 661         case SYS_SETSOCKOPT:
 662                 ret = compat_sys_setsockopt(a0, a1, a[2],
 663                                 compat_ptr(a[3]), a[4]);
 664                 break;
 665         case SYS_GETSOCKOPT:
 666                 ret = compat_sys_getsockopt(a0, a1, a[2],
 667                                 compat_ptr(a[3]), compat_ptr(a[4]));
 668                 break;
 669         case SYS_SENDMSG:
 670                 ret = compat_sys_sendmsg(a0, compat_ptr(a1), a[2]);
 671                 break;
 672         case SYS_RECVMSG:
 673                 ret = compat_sys_recvmsg(a0, compat_ptr(a1), a[2]);
 674                 break;
 675         default:
 676                 ret = -EINVAL;
 677                 break;
 678         }
 679         return ret;
 680 }