1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
4 * Copyright (C) 2015 Richard Weinberger (richard@nod.at)
5 */
6
7 #ifndef __UM_UACCESS_H
8 #define __UM_UACCESS_H
9
10 #include <asm/elf.h>
11 #include <linux/unaligned.h>
12 #include <sysdep/faultinfo.h>
13
14 #define __under_task_size(addr, size) \
15 (((unsigned long) (addr) < TASK_SIZE) && \
16 (((unsigned long) (addr) + (size)) < TASK_SIZE))
17
18 #define __access_ok_vsyscall(addr, size) \
19 (((unsigned long) (addr) >= FIXADDR_USER_START) && \
20 ((unsigned long) (addr) + (size) <= FIXADDR_USER_END) && \
21 ((unsigned long) (addr) + (size) >= (unsigned long)(addr)))
22
23 #define __addr_range_nowrap(addr, size) \
24 ((unsigned long) (addr) <= ((unsigned long) (addr) + (size)))
25
26 extern unsigned long raw_copy_from_user(void *to, const void __user *from, unsigned long n);
27 extern unsigned long raw_copy_to_user(void __user *to, const void *from, unsigned long n);
28 extern unsigned long __clear_user(void __user *mem, unsigned long len);
29 static inline int __access_ok(const void __user *ptr, unsigned long size);
30
31 /* Teach asm-generic/uaccess.h that we have C functions for these. */
32 #define __access_ok __access_ok
33 #define __clear_user __clear_user
34
35 #define INLINE_COPY_FROM_USER
36 #define INLINE_COPY_TO_USER
37
38 #include <asm-generic/uaccess.h>
39
__access_ok(const void __user * ptr,unsigned long size)40 static inline int __access_ok(const void __user *ptr, unsigned long size)
41 {
42 unsigned long addr = (unsigned long)ptr;
43 return __addr_range_nowrap(addr, size) &&
44 (__under_task_size(addr, size) ||
45 __access_ok_vsyscall(addr, size));
46 }
47
48 #define __get_kernel_nofault(dst, src, type, err_label) \
49 do { \
50 int __faulted; \
51 \
52 ___backtrack_faulted(__faulted); \
53 if (__faulted) { \
54 *((type *)dst) = (type) 0; \
55 goto err_label; \
56 } \
57 *((type *)dst) = get_unaligned((type *)(src)); \
58 barrier(); \
59 current->thread.segv_continue = NULL; \
60 } while (0)
61
62 #define __put_kernel_nofault(dst, src, type, err_label) \
63 do { \
64 int __faulted; \
65 \
66 ___backtrack_faulted(__faulted); \
67 if (__faulted) \
68 goto err_label; \
69 put_unaligned(*((type *)src), (type *)(dst)); \
70 barrier(); \
71 current->thread.segv_continue = NULL; \
72 } while (0)
73
74 #endif
75