linux/arch/x86/ia32/sys_ia32.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * sys_ia32.c: Conversion between 32bit and 64bit native syscalls. Based on
   4 *             sys_sparc32
   5 *
   6 * Copyright (C) 2000           VA Linux Co
   7 * Copyright (C) 2000           Don Dugger <n0ano@valinux.com>
   8 * Copyright (C) 1999           Arun Sharma <arun.sharma@intel.com>
   9 * Copyright (C) 1997,1998      Jakub Jelinek (jj@sunsite.mff.cuni.cz)
  10 * Copyright (C) 1997           David S. Miller (davem@caip.rutgers.edu)
  11 * Copyright (C) 2000           Hewlett-Packard Co.
  12 * Copyright (C) 2000           David Mosberger-Tang <davidm@hpl.hp.com>
  13 * Copyright (C) 2000,2001,2002 Andi Kleen, SuSE Labs (x86-64 port)
  14 *
  15 * These routines maintain argument size conversion between 32bit and 64bit
  16 * environment. In 2.5 most of this should be moved to a generic directory.
  17 *
  18 * This file assumes that there is a hole at the end of user address space.
  19 *
  20 * Some of the functions are LE specific currently. These are
  21 * hopefully all marked.  This should be fixed.
  22 */
  23
  24#include <linux/kernel.h>
  25#include <linux/sched.h>
  26#include <linux/fs.h>
  27#include <linux/file.h>
  28#include <linux/signal.h>
  29#include <linux/syscalls.h>
  30#include <linux/times.h>
  31#include <linux/utsname.h>
  32#include <linux/mm.h>
  33#include <linux/uio.h>
  34#include <linux/poll.h>
  35#include <linux/personality.h>
  36#include <linux/stat.h>
  37#include <linux/rwsem.h>
  38#include <linux/compat.h>
  39#include <linux/vfs.h>
  40#include <linux/ptrace.h>
  41#include <linux/highuid.h>
  42#include <linux/sysctl.h>
  43#include <linux/slab.h>
  44#include <linux/sched/task.h>
  45#include <asm/mman.h>
  46#include <asm/types.h>
  47#include <linux/uaccess.h>
  48#include <linux/atomic.h>
  49#include <asm/vgtod.h>
  50#include <asm/ia32.h>
  51
  52#define AA(__x)         ((unsigned long)(__x))
  53
  54
  55COMPAT_SYSCALL_DEFINE3(x86_truncate64, const char __user *, filename,
  56                       unsigned long, offset_low, unsigned long, offset_high)
  57{
  58        return ksys_truncate(filename,
  59                            ((loff_t) offset_high << 32) | offset_low);
  60}
  61
  62COMPAT_SYSCALL_DEFINE3(x86_ftruncate64, unsigned int, fd,
  63                       unsigned long, offset_low, unsigned long, offset_high)
  64{
  65        return ksys_ftruncate(fd, ((loff_t) offset_high << 32) | offset_low);
  66}
  67
  68/*
  69 * Another set for IA32/LFS -- x86_64 struct stat is different due to
  70 * support for 64bit inode numbers.
  71 */
  72static int cp_stat64(struct stat64 __user *ubuf, struct kstat *stat)
  73{
  74        typeof(ubuf->st_uid) uid = 0;
  75        typeof(ubuf->st_gid) gid = 0;
  76        SET_UID(uid, from_kuid_munged(current_user_ns(), stat->uid));
  77        SET_GID(gid, from_kgid_munged(current_user_ns(), stat->gid));
  78        if (!access_ok(VERIFY_WRITE, ubuf, sizeof(struct stat64)) ||
  79            __put_user(huge_encode_dev(stat->dev), &ubuf->st_dev) ||
  80            __put_user(stat->ino, &ubuf->__st_ino) ||
  81            __put_user(stat->ino, &ubuf->st_ino) ||
  82            __put_user(stat->mode, &ubuf->st_mode) ||
  83            __put_user(stat->nlink, &ubuf->st_nlink) ||
  84            __put_user(uid, &ubuf->st_uid) ||
  85            __put_user(gid, &ubuf->st_gid) ||
  86            __put_user(huge_encode_dev(stat->rdev), &ubuf->st_rdev) ||
  87            __put_user(stat->size, &ubuf->st_size) ||
  88            __put_user(stat->atime.tv_sec, &ubuf->st_atime) ||
  89            __put_user(stat->atime.tv_nsec, &ubuf->st_atime_nsec) ||
  90            __put_user(stat->mtime.tv_sec, &ubuf->st_mtime) ||
  91            __put_user(stat->mtime.tv_nsec, &ubuf->st_mtime_nsec) ||
  92            __put_user(stat->ctime.tv_sec, &ubuf->st_ctime) ||
  93            __put_user(stat->ctime.tv_nsec, &ubuf->st_ctime_nsec) ||
  94            __put_user(stat->blksize, &ubuf->st_blksize) ||
  95            __put_user(stat->blocks, &ubuf->st_blocks))
  96                return -EFAULT;
  97        return 0;
  98}
  99
 100COMPAT_SYSCALL_DEFINE2(x86_stat64, const char __user *, filename,
 101                       struct stat64 __user *, statbuf)
 102{
 103        struct kstat stat;
 104        int ret = vfs_stat(filename, &stat);
 105
 106        if (!ret)
 107                ret = cp_stat64(statbuf, &stat);
 108        return ret;
 109}
 110
 111COMPAT_SYSCALL_DEFINE2(x86_lstat64, const char __user *, filename,
 112                       struct stat64 __user *, statbuf)
 113{
 114        struct kstat stat;
 115        int ret = vfs_lstat(filename, &stat);
 116        if (!ret)
 117                ret = cp_stat64(statbuf, &stat);
 118        return ret;
 119}
 120
 121COMPAT_SYSCALL_DEFINE2(x86_fstat64, unsigned int, fd,
 122                       struct stat64 __user *, statbuf)
 123{
 124        struct kstat stat;
 125        int ret = vfs_fstat(fd, &stat);
 126        if (!ret)
 127                ret = cp_stat64(statbuf, &stat);
 128        return ret;
 129}
 130
 131COMPAT_SYSCALL_DEFINE4(x86_fstatat, unsigned int, dfd,
 132                       const char __user *, filename,
 133                       struct stat64 __user *, statbuf, int, flag)
 134{
 135        struct kstat stat;
 136        int error;
 137
 138        error = vfs_fstatat(dfd, filename, &stat, flag);
 139        if (error)
 140                return error;
 141        return cp_stat64(statbuf, &stat);
 142}
 143
 144/*
 145 * Linux/i386 didn't use to be able to handle more than
 146 * 4 system call parameters, so these system calls used a memory
 147 * block for parameter passing..
 148 */
 149
 150struct mmap_arg_struct32 {
 151        unsigned int addr;
 152        unsigned int len;
 153        unsigned int prot;
 154        unsigned int flags;
 155        unsigned int fd;
 156        unsigned int offset;
 157};
 158
 159COMPAT_SYSCALL_DEFINE1(x86_mmap, struct mmap_arg_struct32 __user *, arg)
 160{
 161        struct mmap_arg_struct32 a;
 162
 163        if (copy_from_user(&a, arg, sizeof(a)))
 164                return -EFAULT;
 165
 166        if (a.offset & ~PAGE_MASK)
 167                return -EINVAL;
 168
 169        return ksys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
 170                               a.offset>>PAGE_SHIFT);
 171}
 172
 173/* warning: next two assume little endian */
 174COMPAT_SYSCALL_DEFINE5(x86_pread, unsigned int, fd, char __user *, ubuf,
 175                       u32, count, u32, poslo, u32, poshi)
 176{
 177        return ksys_pread64(fd, ubuf, count,
 178                            ((loff_t)AA(poshi) << 32) | AA(poslo));
 179}
 180
 181COMPAT_SYSCALL_DEFINE5(x86_pwrite, unsigned int, fd, const char __user *, ubuf,
 182                       u32, count, u32, poslo, u32, poshi)
 183{
 184        return ksys_pwrite64(fd, ubuf, count,
 185                             ((loff_t)AA(poshi) << 32) | AA(poslo));
 186}
 187
 188
 189/*
 190 * Some system calls that need sign extended arguments. This could be
 191 * done by a generic wrapper.
 192 */
 193COMPAT_SYSCALL_DEFINE6(x86_fadvise64_64, int, fd, __u32, offset_low,
 194                       __u32, offset_high, __u32, len_low, __u32, len_high,
 195                       int, advice)
 196{
 197        return ksys_fadvise64_64(fd,
 198                                 (((u64)offset_high)<<32) | offset_low,
 199                                 (((u64)len_high)<<32) | len_low,
 200                                 advice);
 201}
 202
 203COMPAT_SYSCALL_DEFINE4(x86_readahead, int, fd, unsigned int, off_lo,
 204                       unsigned int, off_hi, size_t, count)
 205{
 206        return ksys_readahead(fd, ((u64)off_hi << 32) | off_lo, count);
 207}
 208
 209COMPAT_SYSCALL_DEFINE6(x86_sync_file_range, int, fd, unsigned int, off_low,
 210                       unsigned int, off_hi, unsigned int, n_low,
 211                       unsigned int, n_hi, int, flags)
 212{
 213        return ksys_sync_file_range(fd,
 214                                    ((u64)off_hi << 32) | off_low,
 215                                    ((u64)n_hi << 32) | n_low, flags);
 216}
 217
 218COMPAT_SYSCALL_DEFINE5(x86_fadvise64, int, fd, unsigned int, offset_lo,
 219                       unsigned int, offset_hi, size_t, len, int, advice)
 220{
 221        return ksys_fadvise64_64(fd, ((u64)offset_hi << 32) | offset_lo,
 222                                 len, advice);
 223}
 224
 225COMPAT_SYSCALL_DEFINE6(x86_fallocate, int, fd, int, mode,
 226                       unsigned int, offset_lo, unsigned int, offset_hi,
 227                       unsigned int, len_lo, unsigned int, len_hi)
 228{
 229        return ksys_fallocate(fd, mode, ((u64)offset_hi << 32) | offset_lo,
 230                              ((u64)len_hi << 32) | len_lo);
 231}
 232
 233/*
 234 * The 32-bit clone ABI is CONFIG_CLONE_BACKWARDS
 235 */
 236COMPAT_SYSCALL_DEFINE5(x86_clone, unsigned long, clone_flags,
 237                       unsigned long, newsp, int __user *, parent_tidptr,
 238                       unsigned long, tls_val, int __user *, child_tidptr)
 239{
 240        return _do_fork(clone_flags, newsp, 0, parent_tidptr, child_tidptr,
 241                        tls_val);
 242}
 243