arch/x86/ia32/sys_ia32.c

   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
  55 COMPAT_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
  62 COMPAT_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  */
  72 static 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
 100 COMPAT_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
 111 COMPAT_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
 121 COMPAT_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
 131 COMPAT_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
 150 struct 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
 159 COMPAT_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 */
 174 COMPAT_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
 181 COMPAT_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  */
 193 COMPAT_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
 203 COMPAT_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
 209 COMPAT_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
 218 COMPAT_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
 225 COMPAT_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  */
 236 COMPAT_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 }