xref: /linux/arch/x86/kernel/sys_ia32.c (revision 40286d6379aacfcc053253ef78dc78b09addffda)
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 SYSCALL_DEFINE3(ia32_truncate64, const char __user *, filename,
55 		unsigned long, offset_low, unsigned long, offset_high)
56 {
57 	return ksys_truncate(filename,
58 			    ((loff_t) offset_high << 32) | offset_low);
59 }
60 
61 SYSCALL_DEFINE3(ia32_ftruncate64, unsigned int, fd,
62 		unsigned long, offset_low, unsigned long, offset_high)
63 {
64 	return ksys_ftruncate(fd, ((loff_t) offset_high << 32) | offset_low,
65 			FTRUNCATE_LFS);
66 }
67 
68 /* warning: next two assume little endian */
69 SYSCALL_DEFINE5(ia32_pread64, unsigned int, fd, char __user *, ubuf,
70 		u32, count, u32, poslo, u32, poshi)
71 {
72 	return ksys_pread64(fd, ubuf, count,
73 			    ((loff_t)AA(poshi) << 32) | AA(poslo));
74 }
75 
76 SYSCALL_DEFINE5(ia32_pwrite64, unsigned int, fd, const char __user *, ubuf,
77 		u32, count, u32, poslo, u32, poshi)
78 {
79 	return ksys_pwrite64(fd, ubuf, count,
80 			     ((loff_t)AA(poshi) << 32) | AA(poslo));
81 }
82 
83 
84 /*
85  * Some system calls that need sign extended arguments. This could be
86  * done by a generic wrapper.
87  */
88 SYSCALL_DEFINE6(ia32_fadvise64_64, int, fd, __u32, offset_low,
89 		__u32, offset_high, __u32, len_low, __u32, len_high,
90 		int, advice)
91 {
92 	return ksys_fadvise64_64(fd,
93 				 (((u64)offset_high)<<32) | offset_low,
94 				 (((u64)len_high)<<32) | len_low,
95 				 advice);
96 }
97 
98 SYSCALL_DEFINE4(ia32_readahead, int, fd, unsigned int, off_lo,
99 		unsigned int, off_hi, size_t, count)
100 {
101 	return ksys_readahead(fd, ((u64)off_hi << 32) | off_lo, count);
102 }
103 
104 SYSCALL_DEFINE6(ia32_sync_file_range, int, fd, unsigned int, off_low,
105 		unsigned int, off_hi, unsigned int, n_low,
106 		unsigned int, n_hi, int, flags)
107 {
108 	return ksys_sync_file_range(fd,
109 				    ((u64)off_hi << 32) | off_low,
110 				    ((u64)n_hi << 32) | n_low, flags);
111 }
112 
113 SYSCALL_DEFINE5(ia32_fadvise64, int, fd, unsigned int, offset_lo,
114 		unsigned int, offset_hi, size_t, len, int, advice)
115 {
116 	return ksys_fadvise64_64(fd, ((u64)offset_hi << 32) | offset_lo,
117 				 len, advice);
118 }
119 
120 SYSCALL_DEFINE6(ia32_fallocate, int, fd, int, mode,
121 		unsigned int, offset_lo, unsigned int, offset_hi,
122 		unsigned int, len_lo, unsigned int, len_hi)
123 {
124 	return ksys_fallocate(fd, mode, ((u64)offset_hi << 32) | offset_lo,
125 			      ((u64)len_hi << 32) | len_lo);
126 }
127 
128 #ifdef CONFIG_IA32_EMULATION
129 /*
130  * Another set for IA32/LFS -- x86_64 struct stat is different due to
131  * support for 64bit inode numbers.
132  */
133 static int cp_stat64(struct stat64 __user *ubuf, struct kstat *stat)
134 {
135 	typeof(ubuf->st_uid) uid = 0;
136 	typeof(ubuf->st_gid) gid = 0;
137 	SET_UID(uid, from_kuid_munged(current_user_ns(), stat->uid));
138 	SET_GID(gid, from_kgid_munged(current_user_ns(), stat->gid));
139 	if (!user_write_access_begin(ubuf, sizeof(struct stat64)))
140 		return -EFAULT;
141 	unsafe_put_user(huge_encode_dev(stat->dev), &ubuf->st_dev, Efault);
142 	unsafe_put_user(stat->ino, &ubuf->__st_ino, Efault);
143 	unsafe_put_user(stat->ino, &ubuf->st_ino, Efault);
144 	unsafe_put_user(stat->mode, &ubuf->st_mode, Efault);
145 	unsafe_put_user(stat->nlink, &ubuf->st_nlink, Efault);
146 	unsafe_put_user(uid, &ubuf->st_uid, Efault);
147 	unsafe_put_user(gid, &ubuf->st_gid, Efault);
148 	unsafe_put_user(huge_encode_dev(stat->rdev), &ubuf->st_rdev, Efault);
149 	unsafe_put_user(stat->size, &ubuf->st_size, Efault);
150 	unsafe_put_user(stat->atime.tv_sec, &ubuf->st_atime, Efault);
151 	unsafe_put_user(stat->atime.tv_nsec, &ubuf->st_atime_nsec, Efault);
152 	unsafe_put_user(stat->mtime.tv_sec, &ubuf->st_mtime, Efault);
153 	unsafe_put_user(stat->mtime.tv_nsec, &ubuf->st_mtime_nsec, Efault);
154 	unsafe_put_user(stat->ctime.tv_sec, &ubuf->st_ctime, Efault);
155 	unsafe_put_user(stat->ctime.tv_nsec, &ubuf->st_ctime_nsec, Efault);
156 	unsafe_put_user(stat->blksize, &ubuf->st_blksize, Efault);
157 	unsafe_put_user(stat->blocks, &ubuf->st_blocks, Efault);
158 	user_access_end();
159 	return 0;
160 Efault:
161 	user_write_access_end();
162 	return -EFAULT;
163 }
164 
165 COMPAT_SYSCALL_DEFINE2(ia32_stat64, const char __user *, filename,
166 		       struct stat64 __user *, statbuf)
167 {
168 	struct kstat stat;
169 	int ret = vfs_stat(filename, &stat);
170 
171 	if (!ret)
172 		ret = cp_stat64(statbuf, &stat);
173 	return ret;
174 }
175 
176 COMPAT_SYSCALL_DEFINE2(ia32_lstat64, const char __user *, filename,
177 		       struct stat64 __user *, statbuf)
178 {
179 	struct kstat stat;
180 	int ret = vfs_lstat(filename, &stat);
181 	if (!ret)
182 		ret = cp_stat64(statbuf, &stat);
183 	return ret;
184 }
185 
186 COMPAT_SYSCALL_DEFINE2(ia32_fstat64, unsigned int, fd,
187 		       struct stat64 __user *, statbuf)
188 {
189 	struct kstat stat;
190 	int ret = vfs_fstat(fd, &stat);
191 	if (!ret)
192 		ret = cp_stat64(statbuf, &stat);
193 	return ret;
194 }
195 
196 COMPAT_SYSCALL_DEFINE4(ia32_fstatat64, unsigned int, dfd,
197 		       const char __user *, filename,
198 		       struct stat64 __user *, statbuf, int, flag)
199 {
200 	struct kstat stat;
201 	int error;
202 
203 	error = vfs_fstatat(dfd, filename, &stat, flag);
204 	if (error)
205 		return error;
206 	return cp_stat64(statbuf, &stat);
207 }
208 
209 /*
210  * Linux/i386 didn't use to be able to handle more than
211  * 4 system call parameters, so these system calls used a memory
212  * block for parameter passing..
213  */
214 
215 struct mmap_arg_struct32 {
216 	unsigned int addr;
217 	unsigned int len;
218 	unsigned int prot;
219 	unsigned int flags;
220 	unsigned int fd;
221 	unsigned int offset;
222 };
223 
224 COMPAT_SYSCALL_DEFINE1(ia32_mmap, struct mmap_arg_struct32 __user *, arg)
225 {
226 	struct mmap_arg_struct32 a;
227 
228 	if (copy_from_user(&a, arg, sizeof(a)))
229 		return -EFAULT;
230 
231 	if (a.offset & ~PAGE_MASK)
232 		return -EINVAL;
233 
234 	return ksys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
235 			       a.offset>>PAGE_SHIFT);
236 }
237 
238 /*
239  * The 32-bit clone ABI is CONFIG_CLONE_BACKWARDS
240  */
241 COMPAT_SYSCALL_DEFINE5(ia32_clone, unsigned long, clone_flags,
242 		       unsigned long, newsp, int __user *, parent_tidptr,
243 		       unsigned long, tls_val, int __user *, child_tidptr)
244 {
245 	struct kernel_clone_args args = {
246 		.flags		= (clone_flags & ~CSIGNAL),
247 		.pidfd		= parent_tidptr,
248 		.child_tid	= child_tidptr,
249 		.parent_tid	= parent_tidptr,
250 		.exit_signal	= (clone_flags & CSIGNAL),
251 		.stack		= newsp,
252 		.tls		= tls_val,
253 	};
254 
255 	return kernel_clone(&args);
256 }
257 #endif /* CONFIG_IA32_EMULATION */
258