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 
SYSCALL_DEFINE3(ia32_truncate64,const char __user *,filename,unsigned long,offset_low,unsigned long,offset_high)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 
SYSCALL_DEFINE3(ia32_ftruncate64,unsigned int,fd,unsigned long,offset_low,unsigned long,offset_high)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 */
SYSCALL_DEFINE5(ia32_pread64,unsigned int,fd,char __user *,ubuf,u32,count,u32,poslo,u32,poshi)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 
SYSCALL_DEFINE5(ia32_pwrite64,unsigned int,fd,const char __user *,ubuf,u32,count,u32,poslo,u32,poshi)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  */
SYSCALL_DEFINE6(ia32_fadvise64_64,int,fd,__u32,offset_low,__u32,offset_high,__u32,len_low,__u32,len_high,int,advice)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 
SYSCALL_DEFINE4(ia32_readahead,int,fd,unsigned int,off_lo,unsigned int,off_hi,size_t,count)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 
SYSCALL_DEFINE6(ia32_sync_file_range,int,fd,unsigned int,off_low,unsigned int,off_hi,unsigned int,n_low,unsigned int,n_hi,int,flags)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 
SYSCALL_DEFINE5(ia32_fadvise64,int,fd,unsigned int,offset_lo,unsigned int,offset_hi,size_t,len,int,advice)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 
SYSCALL_DEFINE6(ia32_fallocate,int,fd,int,mode,unsigned int,offset_lo,unsigned int,offset_hi,unsigned int,len_lo,unsigned int,len_hi)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  */
cp_stat64(struct stat64 __user * ubuf,struct kstat * stat)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 (!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;
159 Efault:
160 	user_write_access_end();
161 	return -EFAULT;
162 }
163 
COMPAT_SYSCALL_DEFINE2(ia32_stat64,const char __user *,filename,struct stat64 __user *,statbuf)164 COMPAT_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);
169 
170 	if (!ret)
171 		ret = cp_stat64(statbuf, &stat);
172 	return ret;
173 }
174 
COMPAT_SYSCALL_DEFINE2(ia32_lstat64,const char __user *,filename,struct stat64 __user *,statbuf)175 COMPAT_SYSCALL_DEFINE2(ia32_lstat64, const char __user *, filename,
176 		       struct stat64 __user *, statbuf)
177 {
178 	struct kstat stat;
179 	int ret = vfs_lstat(filename, &stat);
180 	if (!ret)
181 		ret = cp_stat64(statbuf, &stat);
182 	return ret;
183 }
184 
COMPAT_SYSCALL_DEFINE2(ia32_fstat64,unsigned int,fd,struct stat64 __user *,statbuf)185 COMPAT_SYSCALL_DEFINE2(ia32_fstat64, unsigned int, fd,
186 		       struct stat64 __user *, statbuf)
187 {
188 	struct kstat stat;
189 	int ret = vfs_fstat(fd, &stat);
190 	if (!ret)
191 		ret = cp_stat64(statbuf, &stat);
192 	return ret;
193 }
194 
COMPAT_SYSCALL_DEFINE4(ia32_fstatat64,unsigned int,dfd,const char __user *,filename,struct stat64 __user *,statbuf,int,flag)195 COMPAT_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, flag);
203 	if (error)
204 		return error;
205 	return cp_stat64(statbuf, &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 
214 struct 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 
COMPAT_SYSCALL_DEFINE1(ia32_mmap,struct mmap_arg_struct32 __user *,arg)223 COMPAT_SYSCALL_DEFINE1(ia32_mmap, struct mmap_arg_struct32 __user *, arg)
224 {
225 	struct mmap_arg_struct32 a;
226 
227 	if (copy_from_user(&a, arg, sizeof(a)))
228 		return -EFAULT;
229 
230 	if (a.offset & ~PAGE_MASK)
231 		return -EINVAL;
232 
233 	return ksys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
234 			       a.offset>>PAGE_SHIFT);
235 }
236 
237 /*
238  * The 32-bit clone ABI is CONFIG_CLONE_BACKWARDS
239  */
COMPAT_SYSCALL_DEFINE5(ia32_clone,unsigned long,clone_flags,unsigned long,newsp,int __user *,parent_tidptr,unsigned long,tls_val,int __user *,child_tidptr)240 COMPAT_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(&args);
255 }
256 #endif /* CONFIG_IA32_EMULATION */
257