xref: /openbmc/linux/arch/x86/kernel/sys_ia32.c (revision 78bb17f7)
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 }
66 
67 /* warning: next two assume little endian */
68 SYSCALL_DEFINE5(ia32_pread64, unsigned int, fd, char __user *, ubuf,
69 		u32, count, u32, poslo, u32, poshi)
70 {
71 	return ksys_pread64(fd, ubuf, count,
72 			    ((loff_t)AA(poshi) << 32) | AA(poslo));
73 }
74 
75 SYSCALL_DEFINE5(ia32_pwrite64, unsigned int, fd, const char __user *, ubuf,
76 		u32, count, u32, poslo, u32, poshi)
77 {
78 	return ksys_pwrite64(fd, ubuf, count,
79 			     ((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  */
87 SYSCALL_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 				 (((u64)offset_high)<<32) | offset_low,
93 				 (((u64)len_high)<<32) | len_low,
94 				 advice);
95 }
96 
97 SYSCALL_DEFINE4(ia32_readahead, int, fd, unsigned int, off_lo,
98 		unsigned int, off_hi, size_t, count)
99 {
100 	return ksys_readahead(fd, ((u64)off_hi << 32) | off_lo, count);
101 }
102 
103 SYSCALL_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 				    ((u64)off_hi << 32) | off_low,
109 				    ((u64)n_hi << 32) | n_low, flags);
110 }
111 
112 SYSCALL_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, ((u64)offset_hi << 32) | offset_lo,
116 				 len, advice);
117 }
118 
119 SYSCALL_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, ((u64)offset_hi << 32) | offset_lo,
124 			      ((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  */
132 static 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 (!access_ok(ubuf, sizeof(struct stat64)) ||
139 	    __put_user(huge_encode_dev(stat->dev), &ubuf->st_dev) ||
140 	    __put_user(stat->ino, &ubuf->__st_ino) ||
141 	    __put_user(stat->ino, &ubuf->st_ino) ||
142 	    __put_user(stat->mode, &ubuf->st_mode) ||
143 	    __put_user(stat->nlink, &ubuf->st_nlink) ||
144 	    __put_user(uid, &ubuf->st_uid) ||
145 	    __put_user(gid, &ubuf->st_gid) ||
146 	    __put_user(huge_encode_dev(stat->rdev), &ubuf->st_rdev) ||
147 	    __put_user(stat->size, &ubuf->st_size) ||
148 	    __put_user(stat->atime.tv_sec, &ubuf->st_atime) ||
149 	    __put_user(stat->atime.tv_nsec, &ubuf->st_atime_nsec) ||
150 	    __put_user(stat->mtime.tv_sec, &ubuf->st_mtime) ||
151 	    __put_user(stat->mtime.tv_nsec, &ubuf->st_mtime_nsec) ||
152 	    __put_user(stat->ctime.tv_sec, &ubuf->st_ctime) ||
153 	    __put_user(stat->ctime.tv_nsec, &ubuf->st_ctime_nsec) ||
154 	    __put_user(stat->blksize, &ubuf->st_blksize) ||
155 	    __put_user(stat->blocks, &ubuf->st_blocks))
156 		return -EFAULT;
157 	return 0;
158 }
159 
160 COMPAT_SYSCALL_DEFINE2(ia32_stat64, const char __user *, filename,
161 		       struct stat64 __user *, statbuf)
162 {
163 	struct kstat stat;
164 	int ret = vfs_stat(filename, &stat);
165 
166 	if (!ret)
167 		ret = cp_stat64(statbuf, &stat);
168 	return ret;
169 }
170 
171 COMPAT_SYSCALL_DEFINE2(ia32_lstat64, const char __user *, filename,
172 		       struct stat64 __user *, statbuf)
173 {
174 	struct kstat stat;
175 	int ret = vfs_lstat(filename, &stat);
176 	if (!ret)
177 		ret = cp_stat64(statbuf, &stat);
178 	return ret;
179 }
180 
181 COMPAT_SYSCALL_DEFINE2(ia32_fstat64, unsigned int, fd,
182 		       struct stat64 __user *, statbuf)
183 {
184 	struct kstat stat;
185 	int ret = vfs_fstat(fd, &stat);
186 	if (!ret)
187 		ret = cp_stat64(statbuf, &stat);
188 	return ret;
189 }
190 
191 COMPAT_SYSCALL_DEFINE4(ia32_fstatat64, unsigned int, dfd,
192 		       const char __user *, filename,
193 		       struct stat64 __user *, statbuf, int, flag)
194 {
195 	struct kstat stat;
196 	int error;
197 
198 	error = vfs_fstatat(dfd, filename, &stat, flag);
199 	if (error)
200 		return error;
201 	return cp_stat64(statbuf, &stat);
202 }
203 
204 /*
205  * Linux/i386 didn't use to be able to handle more than
206  * 4 system call parameters, so these system calls used a memory
207  * block for parameter passing..
208  */
209 
210 struct mmap_arg_struct32 {
211 	unsigned int addr;
212 	unsigned int len;
213 	unsigned int prot;
214 	unsigned int flags;
215 	unsigned int fd;
216 	unsigned int offset;
217 };
218 
219 COMPAT_SYSCALL_DEFINE1(ia32_mmap, struct mmap_arg_struct32 __user *, arg)
220 {
221 	struct mmap_arg_struct32 a;
222 
223 	if (copy_from_user(&a, arg, sizeof(a)))
224 		return -EFAULT;
225 
226 	if (a.offset & ~PAGE_MASK)
227 		return -EINVAL;
228 
229 	return ksys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
230 			       a.offset>>PAGE_SHIFT);
231 }
232 
233 /*
234  * The 32-bit clone ABI is CONFIG_CLONE_BACKWARDS
235  */
236 COMPAT_SYSCALL_DEFINE5(ia32_clone, unsigned long, clone_flags,
237 		       unsigned long, newsp, int __user *, parent_tidptr,
238 		       unsigned long, tls_val, int __user *, child_tidptr)
239 {
240 	struct kernel_clone_args args = {
241 		.flags		= (clone_flags & ~CSIGNAL),
242 		.pidfd		= parent_tidptr,
243 		.child_tid	= child_tidptr,
244 		.parent_tid	= parent_tidptr,
245 		.exit_signal	= (clone_flags & CSIGNAL),
246 		.stack		= newsp,
247 		.tls		= tls_val,
248 	};
249 
250 	if (!legacy_clone_args_valid(&args))
251 		return -EINVAL;
252 
253 	return _do_fork(&args);
254 }
255 #endif /* CONFIG_IA32_EMULATION */
256