arch/s390/kernel/compat_linux.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  S390 version
   4  *    Copyright IBM Corp. 2000
   5  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
   6  *               Gerhard Tonn (ton@de.ibm.com)
   7  *               Thomas Spatzier (tspat@de.ibm.com)
   8  *
   9  *  Conversion between 31bit and 64bit native syscalls.
  10  *
  11  * Heavily inspired by the 32-bit Sparc compat code which is
  12  * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
  13  * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
  14  *
  15  */
  16
  17
  18 #include <linux/kernel.h>
  19 #include <linux/sched.h>
  20 #include <linux/fs.h>
  21 #include <linux/mm.h>
  22 #include <linux/file.h>
  23 #include <linux/signal.h>
  24 #include <linux/resource.h>
  25 #include <linux/times.h>
  26 #include <linux/smp.h>
  27 #include <linux/sem.h>
  28 #include <linux/msg.h>
  29 #include <linux/shm.h>
  30 #include <linux/uio.h>
  31 #include <linux/quota.h>
  32 #include <linux/poll.h>
  33 #include <linux/personality.h>
  34 #include <linux/stat.h>
  35 #include <linux/filter.h>
  36 #include <linux/highmem.h>
  37 #include <linux/highuid.h>
  38 #include <linux/mman.h>
  39 #include <linux/ipv6.h>
  40 #include <linux/in.h>
  41 #include <linux/icmpv6.h>
  42 #include <linux/syscalls.h>
  43 #include <linux/sysctl.h>
  44 #include <linux/binfmts.h>
  45 #include <linux/capability.h>
  46 #include <linux/compat.h>
  47 #include <linux/vfs.h>
  48 #include <linux/ptrace.h>
  49 #include <linux/fadvise.h>
  50 #include <linux/ipc.h>
  51 #include <linux/slab.h>
  52
  53 #include <asm/types.h>
  54 #include <linux/uaccess.h>
  55
  56 #include <net/scm.h>
  57 #include <net/sock.h>
  58
  59 #include "compat_linux.h"
  60
  61 /* For this source file, we want overflow handling. */
  62
  63 #undef high2lowuid
  64 #undef high2lowgid
  65 #undef low2highuid
  66 #undef low2highgid
  67 #undef SET_UID16
  68 #undef SET_GID16
  69 #undef NEW_TO_OLD_UID
  70 #undef NEW_TO_OLD_GID
  71 #undef SET_OLDSTAT_UID
  72 #undef SET_OLDSTAT_GID
  73 #undef SET_STAT_UID
  74 #undef SET_STAT_GID
  75
  76 #define high2lowuid(uid) ((uid) > 65535) ? (u16)overflowuid : (u16)(uid)
  77 #define high2lowgid(gid) ((gid) > 65535) ? (u16)overflowgid : (u16)(gid)
  78 #define low2highuid(uid) ((uid) == (u16)-1) ? (uid_t)-1 : (uid_t)(uid)
  79 #define low2highgid(gid) ((gid) == (u16)-1) ? (gid_t)-1 : (gid_t)(gid)
  80 #define SET_UID16(var, uid)     var = high2lowuid(uid)
  81 #define SET_GID16(var, gid)     var = high2lowgid(gid)
  82 #define NEW_TO_OLD_UID(uid)     high2lowuid(uid)
  83 #define NEW_TO_OLD_GID(gid)     high2lowgid(gid)
  84 #define SET_OLDSTAT_UID(stat, uid)      (stat).st_uid = high2lowuid(uid)
  85 #define SET_OLDSTAT_GID(stat, gid)      (stat).st_gid = high2lowgid(gid)
  86 #define SET_STAT_UID(stat, uid)         (stat).st_uid = high2lowuid(uid)
  87 #define SET_STAT_GID(stat, gid)         (stat).st_gid = high2lowgid(gid)
  88
  89 COMPAT_SYSCALL_DEFINE3(s390_chown16, const char __user *, filename,
  90                        u16, user, u16, group)
  91 {
  92         return ksys_chown(filename, low2highuid(user), low2highgid(group));
  93 }
  94
  95 COMPAT_SYSCALL_DEFINE3(s390_lchown16, const char __user *,
  96                        filename, u16, user, u16, group)
  97 {
  98         return ksys_lchown(filename, low2highuid(user), low2highgid(group));
  99 }
 100
 101 COMPAT_SYSCALL_DEFINE3(s390_fchown16, unsigned int, fd, u16, user, u16, group)
 102 {
 103         return ksys_fchown(fd, low2highuid(user), low2highgid(group));
 104 }
 105
 106 COMPAT_SYSCALL_DEFINE2(s390_setregid16, u16, rgid, u16, egid)
 107 {
 108         return sys_setregid(low2highgid(rgid), low2highgid(egid));
 109 }
 110
 111 COMPAT_SYSCALL_DEFINE1(s390_setgid16, u16, gid)
 112 {
 113         return sys_setgid(low2highgid(gid));
 114 }
 115
 116 COMPAT_SYSCALL_DEFINE2(s390_setreuid16, u16, ruid, u16, euid)
 117 {
 118         return sys_setreuid(low2highuid(ruid), low2highuid(euid));
 119 }
 120
 121 COMPAT_SYSCALL_DEFINE1(s390_setuid16, u16, uid)
 122 {
 123         return sys_setuid(low2highuid(uid));
 124 }
 125
 126 COMPAT_SYSCALL_DEFINE3(s390_setresuid16, u16, ruid, u16, euid, u16, suid)
 127 {
 128         return sys_setresuid(low2highuid(ruid), low2highuid(euid),
 129                              low2highuid(suid));
 130 }
 131
 132 COMPAT_SYSCALL_DEFINE3(s390_getresuid16, u16 __user *, ruidp,
 133                        u16 __user *, euidp, u16 __user *, suidp)
 134 {
 135         const struct cred *cred = current_cred();
 136         int retval;
 137         u16 ruid, euid, suid;
 138
 139         ruid = high2lowuid(from_kuid_munged(cred->user_ns, cred->uid));
 140         euid = high2lowuid(from_kuid_munged(cred->user_ns, cred->euid));
 141         suid = high2lowuid(from_kuid_munged(cred->user_ns, cred->suid));
 142
 143         if (!(retval   = put_user(ruid, ruidp)) &&
 144             !(retval   = put_user(euid, euidp)))
 145                 retval = put_user(suid, suidp);
 146
 147         return retval;
 148 }
 149
 150 COMPAT_SYSCALL_DEFINE3(s390_setresgid16, u16, rgid, u16, egid, u16, sgid)
 151 {
 152         return sys_setresgid(low2highgid(rgid), low2highgid(egid),
 153                              low2highgid(sgid));
 154 }
 155
 156 COMPAT_SYSCALL_DEFINE3(s390_getresgid16, u16 __user *, rgidp,
 157                        u16 __user *, egidp, u16 __user *, sgidp)
 158 {
 159         const struct cred *cred = current_cred();
 160         int retval;
 161         u16 rgid, egid, sgid;
 162
 163         rgid = high2lowgid(from_kgid_munged(cred->user_ns, cred->gid));
 164         egid = high2lowgid(from_kgid_munged(cred->user_ns, cred->egid));
 165         sgid = high2lowgid(from_kgid_munged(cred->user_ns, cred->sgid));
 166
 167         if (!(retval   = put_user(rgid, rgidp)) &&
 168             !(retval   = put_user(egid, egidp)))
 169                 retval = put_user(sgid, sgidp);
 170
 171         return retval;
 172 }
 173
 174 COMPAT_SYSCALL_DEFINE1(s390_setfsuid16, u16, uid)
 175 {
 176         return sys_setfsuid(low2highuid(uid));
 177 }
 178
 179 COMPAT_SYSCALL_DEFINE1(s390_setfsgid16, u16, gid)
 180 {
 181         return sys_setfsgid(low2highgid(gid));
 182 }
 183
 184 static int groups16_to_user(u16 __user *grouplist, struct group_info *group_info)
 185 {
 186         struct user_namespace *user_ns = current_user_ns();
 187         int i;
 188         u16 group;
 189         kgid_t kgid;
 190
 191         for (i = 0; i < group_info->ngroups; i++) {
 192                 kgid = group_info->gid[i];
 193                 group = (u16)from_kgid_munged(user_ns, kgid);
 194                 if (put_user(group, grouplist+i))
 195                         return -EFAULT;
 196         }
 197
 198         return 0;
 199 }
 200
 201 static int groups16_from_user(struct group_info *group_info, u16 __user *grouplist)
 202 {
 203         struct user_namespace *user_ns = current_user_ns();
 204         int i;
 205         u16 group;
 206         kgid_t kgid;
 207
 208         for (i = 0; i < group_info->ngroups; i++) {
 209                 if (get_user(group, grouplist+i))
 210                         return  -EFAULT;
 211
 212                 kgid = make_kgid(user_ns, (gid_t)group);
 213                 if (!gid_valid(kgid))
 214                         return -EINVAL;
 215
 216                 group_info->gid[i] = kgid;
 217         }
 218
 219         return 0;
 220 }
 221
 222 COMPAT_SYSCALL_DEFINE2(s390_getgroups16, int, gidsetsize, u16 __user *, grouplist)
 223 {
 224         const struct cred *cred = current_cred();
 225         int i;
 226
 227         if (gidsetsize < 0)
 228                 return -EINVAL;
 229
 230         get_group_info(cred->group_info);
 231         i = cred->group_info->ngroups;
 232         if (gidsetsize) {
 233                 if (i > gidsetsize) {
 234                         i = -EINVAL;
 235                         goto out;
 236                 }
 237                 if (groups16_to_user(grouplist, cred->group_info)) {
 238                         i = -EFAULT;
 239                         goto out;
 240                 }
 241         }
 242 out:
 243         put_group_info(cred->group_info);
 244         return i;
 245 }
 246
 247 COMPAT_SYSCALL_DEFINE2(s390_setgroups16, int, gidsetsize, u16 __user *, grouplist)
 248 {
 249         struct group_info *group_info;
 250         int retval;
 251
 252         if (!may_setgroups())
 253                 return -EPERM;
 254         if ((unsigned)gidsetsize > NGROUPS_MAX)
 255                 return -EINVAL;
 256
 257         group_info = groups_alloc(gidsetsize);
 258         if (!group_info)
 259                 return -ENOMEM;
 260         retval = groups16_from_user(group_info, grouplist);
 261         if (retval) {
 262                 put_group_info(group_info);
 263                 return retval;
 264         }
 265
 266         groups_sort(group_info);
 267         retval = set_current_groups(group_info);
 268         put_group_info(group_info);
 269
 270         return retval;
 271 }
 272
 273 COMPAT_SYSCALL_DEFINE0(s390_getuid16)
 274 {
 275         return high2lowuid(from_kuid_munged(current_user_ns(), current_uid()));
 276 }
 277
 278 COMPAT_SYSCALL_DEFINE0(s390_geteuid16)
 279 {
 280         return high2lowuid(from_kuid_munged(current_user_ns(), current_euid()));
 281 }
 282
 283 COMPAT_SYSCALL_DEFINE0(s390_getgid16)
 284 {
 285         return high2lowgid(from_kgid_munged(current_user_ns(), current_gid()));
 286 }
 287
 288 COMPAT_SYSCALL_DEFINE0(s390_getegid16)
 289 {
 290         return high2lowgid(from_kgid_munged(current_user_ns(), current_egid()));
 291 }
 292
 293 #ifdef CONFIG_SYSVIPC
 294 COMPAT_SYSCALL_DEFINE5(s390_ipc, uint, call, int, first, compat_ulong_t, second,
 295                 compat_ulong_t, third, compat_uptr_t, ptr)
 296 {
 297         if (call >> 16)         /* hack for backward compatibility */
 298                 return -EINVAL;
 299         return compat_sys_ipc(call, first, second, third, ptr, third);
 300 }
 301 #endif
 302
 303 COMPAT_SYSCALL_DEFINE3(s390_truncate64, const char __user *, path, u32, high, u32, low)
 304 {
 305         return ksys_truncate(path, (unsigned long)high << 32 | low);
 306 }
 307
 308 COMPAT_SYSCALL_DEFINE3(s390_ftruncate64, unsigned int, fd, u32, high, u32, low)
 309 {
 310         return ksys_ftruncate(fd, (unsigned long)high << 32 | low);
 311 }
 312
 313 COMPAT_SYSCALL_DEFINE5(s390_pread64, unsigned int, fd, char __user *, ubuf,
 314                        compat_size_t, count, u32, high, u32, low)
 315 {
 316         if ((compat_ssize_t) count < 0)
 317                 return -EINVAL;
 318         return ksys_pread64(fd, ubuf, count, (unsigned long)high << 32 | low);
 319 }
 320
 321 COMPAT_SYSCALL_DEFINE5(s390_pwrite64, unsigned int, fd, const char __user *, ubuf,
 322                        compat_size_t, count, u32, high, u32, low)
 323 {
 324         if ((compat_ssize_t) count < 0)
 325                 return -EINVAL;
 326         return ksys_pwrite64(fd, ubuf, count, (unsigned long)high << 32 | low);
 327 }
 328
 329 COMPAT_SYSCALL_DEFINE4(s390_readahead, int, fd, u32, high, u32, low, s32, count)
 330 {
 331         return ksys_readahead(fd, (unsigned long)high << 32 | low, count);
 332 }
 333
 334 struct stat64_emu31 {
 335         unsigned long long  st_dev;
 336         unsigned int    __pad1;
 337 #define STAT64_HAS_BROKEN_ST_INO        1
 338         u32             __st_ino;
 339         unsigned int    st_mode;
 340         unsigned int    st_nlink;
 341         u32             st_uid;
 342         u32             st_gid;
 343         unsigned long long  st_rdev;
 344         unsigned int    __pad3;
 345         long            st_size;
 346         u32             st_blksize;
 347         unsigned char   __pad4[4];
 348         u32             __pad5;     /* future possible st_blocks high bits */
 349         u32             st_blocks;  /* Number 512-byte blocks allocated. */
 350         u32             st_atime;
 351         u32             __pad6;
 352         u32             st_mtime;
 353         u32             __pad7;
 354         u32             st_ctime;
 355         u32             __pad8;     /* will be high 32 bits of ctime someday */
 356         unsigned long   st_ino;
 357 };
 358
 359 static int cp_stat64(struct stat64_emu31 __user *ubuf, struct kstat *stat)
 360 {
 361         struct stat64_emu31 tmp;
 362
 363         memset(&tmp, 0, sizeof(tmp));
 364
 365         tmp.st_dev = huge_encode_dev(stat->dev);
 366         tmp.st_ino = stat->ino;
 367         tmp.__st_ino = (u32)stat->ino;
 368         tmp.st_mode = stat->mode;
 369         tmp.st_nlink = (unsigned int)stat->nlink;
 370         tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid);
 371         tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid);
 372         tmp.st_rdev = huge_encode_dev(stat->rdev);
 373         tmp.st_size = stat->size;
 374         tmp.st_blksize = (u32)stat->blksize;
 375         tmp.st_blocks = (u32)stat->blocks;
 376         tmp.st_atime = (u32)stat->atime.tv_sec;
 377         tmp.st_mtime = (u32)stat->mtime.tv_sec;
 378         tmp.st_ctime = (u32)stat->ctime.tv_sec;
 379
 380         return copy_to_user(ubuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
 381 }
 382
 383 COMPAT_SYSCALL_DEFINE2(s390_stat64, const char __user *, filename, struct stat64_emu31 __user *, statbuf)
 384 {
 385         struct kstat stat;
 386         int ret = vfs_stat(filename, &stat);
 387         if (!ret)
 388                 ret = cp_stat64(statbuf, &stat);
 389         return ret;
 390 }
 391
 392 COMPAT_SYSCALL_DEFINE2(s390_lstat64, const char __user *, filename, struct stat64_emu31 __user *, statbuf)
 393 {
 394         struct kstat stat;
 395         int ret = vfs_lstat(filename, &stat);
 396         if (!ret)
 397                 ret = cp_stat64(statbuf, &stat);
 398         return ret;
 399 }
 400
 401 COMPAT_SYSCALL_DEFINE2(s390_fstat64, unsigned int, fd, struct stat64_emu31 __user *, statbuf)
 402 {
 403         struct kstat stat;
 404         int ret = vfs_fstat(fd, &stat);
 405         if (!ret)
 406                 ret = cp_stat64(statbuf, &stat);
 407         return ret;
 408 }
 409
 410 COMPAT_SYSCALL_DEFINE4(s390_fstatat64, unsigned int, dfd, const char __user *, filename,
 411                        struct stat64_emu31 __user *, statbuf, int, flag)
 412 {
 413         struct kstat stat;
 414         int error;
 415
 416         error = vfs_fstatat(dfd, filename, &stat, flag);
 417         if (error)
 418                 return error;
 419         return cp_stat64(statbuf, &stat);
 420 }
 421
 422 /*
 423  * Linux/i386 didn't use to be able to handle more than
 424  * 4 system call parameters, so these system calls used a memory
 425  * block for parameter passing..
 426  */
 427
 428 struct mmap_arg_struct_emu31 {
 429         compat_ulong_t addr;
 430         compat_ulong_t len;
 431         compat_ulong_t prot;
 432         compat_ulong_t flags;
 433         compat_ulong_t fd;
 434         compat_ulong_t offset;
 435 };
 436
 437 COMPAT_SYSCALL_DEFINE1(s390_old_mmap, struct mmap_arg_struct_emu31 __user *, arg)
 438 {
 439         struct mmap_arg_struct_emu31 a;
 440
 441         if (copy_from_user(&a, arg, sizeof(a)))
 442                 return -EFAULT;
 443         if (a.offset & ~PAGE_MASK)
 444                 return -EINVAL;
 445         return ksys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
 446                                a.offset >> PAGE_SHIFT);
 447 }
 448
 449 COMPAT_SYSCALL_DEFINE1(s390_mmap2, struct mmap_arg_struct_emu31 __user *, arg)
 450 {
 451         struct mmap_arg_struct_emu31 a;
 452
 453         if (copy_from_user(&a, arg, sizeof(a)))
 454                 return -EFAULT;
 455         return ksys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
 456 }
 457
 458 COMPAT_SYSCALL_DEFINE3(s390_read, unsigned int, fd, char __user *, buf, compat_size_t, count)
 459 {
 460         if ((compat_ssize_t) count < 0)
 461                 return -EINVAL;
 462
 463         return ksys_read(fd, buf, count);
 464 }
 465
 466 COMPAT_SYSCALL_DEFINE3(s390_write, unsigned int, fd, const char __user *, buf, compat_size_t, count)
 467 {
 468         if ((compat_ssize_t) count < 0)
 469                 return -EINVAL;
 470
 471         return ksys_write(fd, buf, count);
 472 }
 473
 474 /*
 475  * 31 bit emulation wrapper functions for sys_fadvise64/fadvise64_64.
 476  * These need to rewrite the advise values for POSIX_FADV_{DONTNEED,NOREUSE}
 477  * because the 31 bit values differ from the 64 bit values.
 478  */
 479
 480 COMPAT_SYSCALL_DEFINE5(s390_fadvise64, int, fd, u32, high, u32, low, compat_size_t, len, int, advise)
 481 {
 482         if (advise == 4)
 483                 advise = POSIX_FADV_DONTNEED;
 484         else if (advise == 5)
 485                 advise = POSIX_FADV_NOREUSE;
 486         return ksys_fadvise64_64(fd, (unsigned long)high << 32 | low, len,
 487                                  advise);
 488 }
 489
 490 struct fadvise64_64_args {
 491         int fd;
 492         long long offset;
 493         long long len;
 494         int advice;
 495 };
 496
 497 COMPAT_SYSCALL_DEFINE1(s390_fadvise64_64, struct fadvise64_64_args __user *, args)
 498 {
 499         struct fadvise64_64_args a;
 500
 501         if ( copy_from_user(&a, args, sizeof(a)) )
 502                 return -EFAULT;
 503         if (a.advice == 4)
 504                 a.advice = POSIX_FADV_DONTNEED;
 505         else if (a.advice == 5)
 506                 a.advice = POSIX_FADV_NOREUSE;
 507         return ksys_fadvise64_64(a.fd, a.offset, a.len, a.advice);
 508 }
 509
 510 COMPAT_SYSCALL_DEFINE6(s390_sync_file_range, int, fd, u32, offhigh, u32, offlow,
 511                        u32, nhigh, u32, nlow, unsigned int, flags)
 512 {
 513         return ksys_sync_file_range(fd, ((loff_t)offhigh << 32) + offlow,
 514                                    ((u64)nhigh << 32) + nlow, flags);
 515 }
 516
 517 COMPAT_SYSCALL_DEFINE6(s390_fallocate, int, fd, int, mode, u32, offhigh, u32, offlow,
 518                        u32, lenhigh, u32, lenlow)
 519 {
 520         return ksys_fallocate(fd, mode, ((loff_t)offhigh << 32) + offlow,
 521                               ((u64)lenhigh << 32) + lenlow);
 522 }