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
54SYSCALL_DEFINE3(ia32_truncate64, const char __user *, filename,
55 unsigned long, offset_low, unsigned long, offset_high)
56{
57 return ksys_truncate(pathname: filename,
58 length: ((loff_t) offset_high << 32) | offset_low);
59}
60
61SYSCALL_DEFINE3(ia32_ftruncate64, unsigned int, fd,
62 unsigned long, offset_low, unsigned long, offset_high)
63{
64 return ksys_ftruncate(fd, length: ((loff_t) offset_high << 32) | offset_low);
65}
66
67/* warning: next two assume little endian */
68SYSCALL_DEFINE5(ia32_pread64, unsigned int, fd, char __user *, ubuf,
69 u32, count, u32, poslo, u32, poshi)
70{
71 return ksys_pread64(fd, buf: ubuf, count,
72 pos: ((loff_t)AA(poshi) << 32) | AA(poslo));
73}
74
75SYSCALL_DEFINE5(ia32_pwrite64, unsigned int, fd, const char __user *, ubuf,
76 u32, count, u32, poslo, u32, poshi)
77{
78 return ksys_pwrite64(fd, buf: ubuf, count,
79 pos: ((loff_t)AA(poshi) << 32) | AA(poslo));
80}
81
82
83/*
84 * Some system calls that need sign extended arguments. This could be
85 * done by a generic wrapper.
86 */
87SYSCALL_DEFINE6(ia32_fadvise64_64, int, fd, __u32, offset_low,
88 __u32, offset_high, __u32, len_low, __u32, len_high,
89 int, advice)
90{
91 return ksys_fadvise64_64(fd,
92 offset: (((u64)offset_high)<<32) | offset_low,
93 len: (((u64)len_high)<<32) | len_low,
94 advice);
95}
96
97SYSCALL_DEFINE4(ia32_readahead, int, fd, unsigned int, off_lo,
98 unsigned int, off_hi, size_t, count)
99{
100 return ksys_readahead(fd, offset: ((u64)off_hi << 32) | off_lo, count);
101}
102
103SYSCALL_DEFINE6(ia32_sync_file_range, int, fd, unsigned int, off_low,
104 unsigned int, off_hi, unsigned int, n_low,
105 unsigned int, n_hi, int, flags)
106{
107 return ksys_sync_file_range(fd,
108 offset: ((u64)off_hi << 32) | off_low,
109 nbytes: ((u64)n_hi << 32) | n_low, flags);
110}
111
112SYSCALL_DEFINE5(ia32_fadvise64, int, fd, unsigned int, offset_lo,
113 unsigned int, offset_hi, size_t, len, int, advice)
114{
115 return ksys_fadvise64_64(fd, offset: ((u64)offset_hi << 32) | offset_lo,
116 len, advice);
117}
118
119SYSCALL_DEFINE6(ia32_fallocate, int, fd, int, mode,
120 unsigned int, offset_lo, unsigned int, offset_hi,
121 unsigned int, len_lo, unsigned int, len_hi)
122{
123 return ksys_fallocate(fd, mode, offset: ((u64)offset_hi << 32) | offset_lo,
124 len: ((u64)len_hi << 32) | len_lo);
125}
126
127#ifdef CONFIG_IA32_EMULATION
128/*
129 * Another set for IA32/LFS -- x86_64 struct stat is different due to
130 * support for 64bit inode numbers.
131 */
132static int cp_stat64(struct stat64 __user *ubuf, struct kstat *stat)
133{
134 typeof(ubuf->st_uid) uid = 0;
135 typeof(ubuf->st_gid) gid = 0;
136 SET_UID(uid, from_kuid_munged(current_user_ns(), stat->uid));
137 SET_GID(gid, from_kgid_munged(current_user_ns(), stat->gid));
138 if (!user_write_access_begin(ubuf, sizeof(struct stat64)))
139 return -EFAULT;
140 unsafe_put_user(huge_encode_dev(stat->dev), &ubuf->st_dev, Efault);
141 unsafe_put_user(stat->ino, &ubuf->__st_ino, Efault);
142 unsafe_put_user(stat->ino, &ubuf->st_ino, Efault);
143 unsafe_put_user(stat->mode, &ubuf->st_mode, Efault);
144 unsafe_put_user(stat->nlink, &ubuf->st_nlink, Efault);
145 unsafe_put_user(uid, &ubuf->st_uid, Efault);
146 unsafe_put_user(gid, &ubuf->st_gid, Efault);
147 unsafe_put_user(huge_encode_dev(stat->rdev), &ubuf->st_rdev, Efault);
148 unsafe_put_user(stat->size, &ubuf->st_size, Efault);
149 unsafe_put_user(stat->atime.tv_sec, &ubuf->st_atime, Efault);
150 unsafe_put_user(stat->atime.tv_nsec, &ubuf->st_atime_nsec, Efault);
151 unsafe_put_user(stat->mtime.tv_sec, &ubuf->st_mtime, Efault);
152 unsafe_put_user(stat->mtime.tv_nsec, &ubuf->st_mtime_nsec, Efault);
153 unsafe_put_user(stat->ctime.tv_sec, &ubuf->st_ctime, Efault);
154 unsafe_put_user(stat->ctime.tv_nsec, &ubuf->st_ctime_nsec, Efault);
155 unsafe_put_user(stat->blksize, &ubuf->st_blksize, Efault);
156 unsafe_put_user(stat->blocks, &ubuf->st_blocks, Efault);
157 user_access_end();
158 return 0;
159Efault:
160 user_write_access_end();
161 return -EFAULT;
162}
163
164COMPAT_SYSCALL_DEFINE2(ia32_stat64, const char __user *, filename,
165 struct stat64 __user *, statbuf)
166{
167 struct kstat stat;
168 int ret = vfs_stat(filename, stat: &stat);
169
170 if (!ret)
171 ret = cp_stat64(ubuf: statbuf, stat: &stat);
172 return ret;
173}
174
175COMPAT_SYSCALL_DEFINE2(ia32_lstat64, const char __user *, filename,
176 struct stat64 __user *, statbuf)
177{
178 struct kstat stat;
179 int ret = vfs_lstat(name: filename, stat: &stat);
180 if (!ret)
181 ret = cp_stat64(ubuf: statbuf, stat: &stat);
182 return ret;
183}
184
185COMPAT_SYSCALL_DEFINE2(ia32_fstat64, unsigned int, fd,
186 struct stat64 __user *, statbuf)
187{
188 struct kstat stat;
189 int ret = vfs_fstat(fd, stat: &stat);
190 if (!ret)
191 ret = cp_stat64(ubuf: statbuf, stat: &stat);
192 return ret;
193}
194
195COMPAT_SYSCALL_DEFINE4(ia32_fstatat64, unsigned int, dfd,
196 const char __user *, filename,
197 struct stat64 __user *, statbuf, int, flag)
198{
199 struct kstat stat;
200 int error;
201
202 error = vfs_fstatat(dfd, filename, stat: &stat, flags: flag);
203 if (error)
204 return error;
205 return cp_stat64(ubuf: statbuf, stat: &stat);
206}
207
208/*
209 * Linux/i386 didn't use to be able to handle more than
210 * 4 system call parameters, so these system calls used a memory
211 * block for parameter passing..
212 */
213
214struct mmap_arg_struct32 {
215 unsigned int addr;
216 unsigned int len;
217 unsigned int prot;
218 unsigned int flags;
219 unsigned int fd;
220 unsigned int offset;
221};
222
223COMPAT_SYSCALL_DEFINE1(ia32_mmap, struct mmap_arg_struct32 __user *, arg)
224{
225 struct mmap_arg_struct32 a;
226
227 if (copy_from_user(to: &a, from: arg, n: sizeof(a)))
228 return -EFAULT;
229
230 if (a.offset & ~PAGE_MASK)
231 return -EINVAL;
232
233 return ksys_mmap_pgoff(addr: a.addr, len: a.len, prot: a.prot, flags: a.flags, fd: a.fd,
234 pgoff: a.offset>>PAGE_SHIFT);
235}
236
237/*
238 * The 32-bit clone ABI is CONFIG_CLONE_BACKWARDS
239 */
240COMPAT_SYSCALL_DEFINE5(ia32_clone, unsigned long, clone_flags,
241 unsigned long, newsp, int __user *, parent_tidptr,
242 unsigned long, tls_val, int __user *, child_tidptr)
243{
244 struct kernel_clone_args args = {
245 .flags = (clone_flags & ~CSIGNAL),
246 .pidfd = parent_tidptr,
247 .child_tid = child_tidptr,
248 .parent_tid = parent_tidptr,
249 .exit_signal = (clone_flags & CSIGNAL),
250 .stack = newsp,
251 .tls = tls_val,
252 };
253
254 return kernel_clone(kargs: &args);
255}
256#endif /* CONFIG_IA32_EMULATION */
257

source code of linux/arch/x86/kernel/sys_ia32.c