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1/*
2 * arch/arm/include/asm/uaccess.h
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 */
8#ifndef _ASMARM_UACCESS_H
9#define _ASMARM_UACCESS_H
10
11/*
12 * User space memory access functions
13 */
14#include <linux/string.h>
15#include <linux/thread_info.h>
16#include <asm/errno.h>
17#include <asm/memory.h>
18#include <asm/domain.h>
19#include <asm/system.h>
20#include <asm/unified.h>
21
22#define VERIFY_READ 0
23#define VERIFY_WRITE 1
24
25/*
26 * The exception table consists of pairs of addresses: the first is the
27 * address of an instruction that is allowed to fault, and the second is
28 * the address at which the program should continue. No registers are
29 * modified, so it is entirely up to the continuation code to figure out
30 * what to do.
31 *
32 * All the routines below use bits of fixup code that are out of line
33 * with the main instruction path. This means when everything is well,
34 * we don't even have to jump over them. Further, they do not intrude
35 * on our cache or tlb entries.
36 */
37
38struct exception_table_entry
39{
40 unsigned long insn, fixup;
41};
42
43extern int fixup_exception(struct pt_regs *regs);
44
45/*
46 * These two are intentionally not defined anywhere - if the kernel
47 * code generates any references to them, that's a bug.
48 */
49extern int __get_user_bad(void);
50extern int __put_user_bad(void);
51
52/*
53 * Note that this is actually 0x1,0000,0000
54 */
55#define KERNEL_DS 0x00000000
56#define get_ds() (KERNEL_DS)
57
58#ifdef CONFIG_MMU
59
60#define USER_DS TASK_SIZE
61#define get_fs() (current_thread_info()->addr_limit)
62
63static inline void set_fs(mm_segment_t fs)
64{
65 current_thread_info()->addr_limit = fs;
66 modify_domain(DOMAIN_KERNEL, fs ? DOMAIN_CLIENT : DOMAIN_MANAGER);
67}
68
69#define segment_eq(a,b) ((a) == (b))
70
71#define __addr_ok(addr) ({ \
72 unsigned long flag; \
73 __asm__("cmp %2, %0; movlo %0, #0" \
74 : "=&r" (flag) \
75 : "0" (current_thread_info()->addr_limit), "r" (addr) \
76 : "cc"); \
77 (flag == 0); })
78
79/* We use 33-bit arithmetic here... */
80#define __range_ok(addr,size) ({ \
81 unsigned long flag, roksum; \
82 __chk_user_ptr(addr); \
83 __asm__("adds %1, %2, %3; sbcccs %1, %1, %0; movcc %0, #0" \
84 : "=&r" (flag), "=&r" (roksum) \
85 : "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit) \
86 : "cc"); \
87 flag; })
88
89/*
90 * Single-value transfer routines. They automatically use the right
91 * size if we just have the right pointer type. Note that the functions
92 * which read from user space (*get_*) need to take care not to leak
93 * kernel data even if the calling code is buggy and fails to check
94 * the return value. This means zeroing out the destination variable
95 * or buffer on error. Normally this is done out of line by the
96 * fixup code, but there are a few places where it intrudes on the
97 * main code path. When we only write to user space, there is no
98 * problem.
99 */
100extern int __get_user_1(void *);
101extern int __get_user_2(void *);
102extern int __get_user_4(void *);
103
104#define __get_user_x(__r2,__p,__e,__s,__i...) \
105 __asm__ __volatile__ ( \
106 __asmeq("%0", "r0") __asmeq("%1", "r2") \
107 "bl __get_user_" #__s \
108 : "=&r" (__e), "=r" (__r2) \
109 : "0" (__p) \
110 : __i, "cc")
111
112#define get_user(x,p) \
113 ({ \
114 register const typeof(*(p)) __user *__p asm("r0") = (p);\
115 register unsigned long __r2 asm("r2"); \
116 register int __e asm("r0"); \
117 switch (sizeof(*(__p))) { \
118 case 1: \
119 __get_user_x(__r2, __p, __e, 1, "lr"); \
120 break; \
121 case 2: \
122 __get_user_x(__r2, __p, __e, 2, "r3", "lr"); \
123 break; \
124 case 4: \
125 __get_user_x(__r2, __p, __e, 4, "lr"); \
126 break; \
127 default: __e = __get_user_bad(); break; \
128 } \
129 x = (typeof(*(p))) __r2; \
130 __e; \
131 })
132
133extern int __put_user_1(void *, unsigned int);
134extern int __put_user_2(void *, unsigned int);
135extern int __put_user_4(void *, unsigned int);
136extern int __put_user_8(void *, unsigned long long);
137
138#define __put_user_x(__r2,__p,__e,__s) \
139 __asm__ __volatile__ ( \
140 __asmeq("%0", "r0") __asmeq("%2", "r2") \
141 "bl __put_user_" #__s \
142 : "=&r" (__e) \
143 : "0" (__p), "r" (__r2) \
144 : "ip", "lr", "cc")
145
146#define put_user(x,p) \
147 ({ \
148 register const typeof(*(p)) __r2 asm("r2") = (x); \
149 register const typeof(*(p)) __user *__p asm("r0") = (p);\
150 register int __e asm("r0"); \
151 switch (sizeof(*(__p))) { \
152 case 1: \
153 __put_user_x(__r2, __p, __e, 1); \
154 break; \
155 case 2: \
156 __put_user_x(__r2, __p, __e, 2); \
157 break; \
158 case 4: \
159 __put_user_x(__r2, __p, __e, 4); \
160 break; \
161 case 8: \
162 __put_user_x(__r2, __p, __e, 8); \
163 break; \
164 default: __e = __put_user_bad(); break; \
165 } \
166 __e; \
167 })
168
169#else /* CONFIG_MMU */
170
171/*
172 * uClinux has only one addr space, so has simplified address limits.
173 */
174#define USER_DS KERNEL_DS
175
176#define segment_eq(a,b) (1)
177#define __addr_ok(addr) (1)
178#define __range_ok(addr,size) (0)
179#define get_fs() (KERNEL_DS)
180
181static inline void set_fs(mm_segment_t fs)
182{
183}
184
185#define get_user(x,p) __get_user(x,p)
186#define put_user(x,p) __put_user(x,p)
187
188#endif /* CONFIG_MMU */
189
190#define access_ok(type,addr,size) (__range_ok(addr,size) == 0)
191
192/*
193 * The "__xxx" versions of the user access functions do not verify the
194 * address space - it must have been done previously with a separate
195 * "access_ok()" call.
196 *
197 * The "xxx_error" versions set the third argument to EFAULT if an
198 * error occurs, and leave it unchanged on success. Note that these
199 * versions are void (ie, don't return a value as such).
200 */
201#define __get_user(x,ptr) \
202({ \
203 long __gu_err = 0; \
204 __get_user_err((x),(ptr),__gu_err); \
205 __gu_err; \
206})
207
208#define __get_user_error(x,ptr,err) \
209({ \
210 __get_user_err((x),(ptr),err); \
211 (void) 0; \
212})
213
214#define __get_user_err(x,ptr,err) \
215do { \
216 unsigned long __gu_addr = (unsigned long)(ptr); \
217 unsigned long __gu_val; \
218 __chk_user_ptr(ptr); \
219 switch (sizeof(*(ptr))) { \
220 case 1: __get_user_asm_byte(__gu_val,__gu_addr,err); break; \
221 case 2: __get_user_asm_half(__gu_val,__gu_addr,err); break; \
222 case 4: __get_user_asm_word(__gu_val,__gu_addr,err); break; \
223 default: (__gu_val) = __get_user_bad(); \
224 } \
225 (x) = (__typeof__(*(ptr)))__gu_val; \
226} while (0)
227
228#define __get_user_asm_byte(x,addr,err) \
229 __asm__ __volatile__( \
230 "1: " T(ldrb) " %1,[%2],#0\n" \
231 "2:\n" \
232 " .pushsection .fixup,\"ax\"\n" \
233 " .align 2\n" \
234 "3: mov %0, %3\n" \
235 " mov %1, #0\n" \
236 " b 2b\n" \
237 " .popsection\n" \
238 " .pushsection __ex_table,\"a\"\n" \
239 " .align 3\n" \
240 " .long 1b, 3b\n" \
241 " .popsection" \
242 : "+r" (err), "=&r" (x) \
243 : "r" (addr), "i" (-EFAULT) \
244 : "cc")
245
246#ifndef __ARMEB__
247#define __get_user_asm_half(x,__gu_addr,err) \
248({ \
249 unsigned long __b1, __b2; \
250 __get_user_asm_byte(__b1, __gu_addr, err); \
251 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
252 (x) = __b1 | (__b2 << 8); \
253})
254#else
255#define __get_user_asm_half(x,__gu_addr,err) \
256({ \
257 unsigned long __b1, __b2; \
258 __get_user_asm_byte(__b1, __gu_addr, err); \
259 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
260 (x) = (__b1 << 8) | __b2; \
261})
262#endif
263
264#define __get_user_asm_word(x,addr,err) \
265 __asm__ __volatile__( \
266 "1: " T(ldr) " %1,[%2],#0\n" \
267 "2:\n" \
268 " .pushsection .fixup,\"ax\"\n" \
269 " .align 2\n" \
270 "3: mov %0, %3\n" \
271 " mov %1, #0\n" \
272 " b 2b\n" \
273 " .popsection\n" \
274 " .pushsection __ex_table,\"a\"\n" \
275 " .align 3\n" \
276 " .long 1b, 3b\n" \
277 " .popsection" \
278 : "+r" (err), "=&r" (x) \
279 : "r" (addr), "i" (-EFAULT) \
280 : "cc")
281
282#define __put_user(x,ptr) \
283({ \
284 long __pu_err = 0; \
285 __put_user_err((x),(ptr),__pu_err); \
286 __pu_err; \
287})
288
289#define __put_user_error(x,ptr,err) \
290({ \
291 __put_user_err((x),(ptr),err); \
292 (void) 0; \
293})
294
295#define __put_user_err(x,ptr,err) \
296do { \
297 unsigned long __pu_addr = (unsigned long)(ptr); \
298 __typeof__(*(ptr)) __pu_val = (x); \
299 __chk_user_ptr(ptr); \
300 switch (sizeof(*(ptr))) { \
301 case 1: __put_user_asm_byte(__pu_val,__pu_addr,err); break; \
302 case 2: __put_user_asm_half(__pu_val,__pu_addr,err); break; \
303 case 4: __put_user_asm_word(__pu_val,__pu_addr,err); break; \
304 case 8: __put_user_asm_dword(__pu_val,__pu_addr,err); break; \
305 default: __put_user_bad(); \
306 } \
307} while (0)
308
309#define __put_user_asm_byte(x,__pu_addr,err) \
310 __asm__ __volatile__( \
311 "1: " T(strb) " %1,[%2],#0\n" \
312 "2:\n" \
313 " .pushsection .fixup,\"ax\"\n" \
314 " .align 2\n" \
315 "3: mov %0, %3\n" \
316 " b 2b\n" \
317 " .popsection\n" \
318 " .pushsection __ex_table,\"a\"\n" \
319 " .align 3\n" \
320 " .long 1b, 3b\n" \
321 " .popsection" \
322 : "+r" (err) \
323 : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
324 : "cc")
325
326#ifndef __ARMEB__
327#define __put_user_asm_half(x,__pu_addr,err) \
328({ \
329 unsigned long __temp = (unsigned long)(x); \
330 __put_user_asm_byte(__temp, __pu_addr, err); \
331 __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \
332})
333#else
334#define __put_user_asm_half(x,__pu_addr,err) \
335({ \
336 unsigned long __temp = (unsigned long)(x); \
337 __put_user_asm_byte(__temp >> 8, __pu_addr, err); \
338 __put_user_asm_byte(__temp, __pu_addr + 1, err); \
339})
340#endif
341
342#define __put_user_asm_word(x,__pu_addr,err) \
343 __asm__ __volatile__( \
344 "1: " T(str) " %1,[%2],#0\n" \
345 "2:\n" \
346 " .pushsection .fixup,\"ax\"\n" \
347 " .align 2\n" \
348 "3: mov %0, %3\n" \
349 " b 2b\n" \
350 " .popsection\n" \
351 " .pushsection __ex_table,\"a\"\n" \
352 " .align 3\n" \
353 " .long 1b, 3b\n" \
354 " .popsection" \
355 : "+r" (err) \
356 : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
357 : "cc")
358
359#ifndef __ARMEB__
360#define __reg_oper0 "%R2"
361#define __reg_oper1 "%Q2"
362#else
363#define __reg_oper0 "%Q2"
364#define __reg_oper1 "%R2"
365#endif
366
367#define __put_user_asm_dword(x,__pu_addr,err) \
368 __asm__ __volatile__( \
369 ARM( "1: " T(str) " " __reg_oper1 ", [%1], #4\n" ) \
370 ARM( "2: " T(str) " " __reg_oper0 ", [%1]\n" ) \
371 THUMB( "1: " T(str) " " __reg_oper1 ", [%1]\n" ) \
372 THUMB( "2: " T(str) " " __reg_oper0 ", [%1, #4]\n" ) \
373 "3:\n" \
374 " .pushsection .fixup,\"ax\"\n" \
375 " .align 2\n" \
376 "4: mov %0, %3\n" \
377 " b 3b\n" \
378 " .popsection\n" \
379 " .pushsection __ex_table,\"a\"\n" \
380 " .align 3\n" \
381 " .long 1b, 4b\n" \
382 " .long 2b, 4b\n" \
383 " .popsection" \
384 : "+r" (err), "+r" (__pu_addr) \
385 : "r" (x), "i" (-EFAULT) \
386 : "cc")
387
388
389#ifdef CONFIG_MMU
390extern unsigned long __must_check __copy_from_user(void *to, const void __user *from, unsigned long n);
391extern unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n);
392extern unsigned long __must_check __copy_to_user_std(void __user *to, const void *from, unsigned long n);
393extern unsigned long __must_check __clear_user(void __user *addr, unsigned long n);
394extern unsigned long __must_check __clear_user_std(void __user *addr, unsigned long n);
395#else
396#define __copy_from_user(to,from,n) (memcpy(to, (void __force *)from, n), 0)
397#define __copy_to_user(to,from,n) (memcpy((void __force *)to, from, n), 0)
398#define __clear_user(addr,n) (memset((void __force *)addr, 0, n), 0)
399#endif
400
401extern unsigned long __must_check __strncpy_from_user(char *to, const char __user *from, unsigned long count);
402extern unsigned long __must_check __strnlen_user(const char __user *s, long n);
403
404static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n)
405{
406 if (access_ok(VERIFY_READ, from, n))
407 n = __copy_from_user(to, from, n);
408 else /* security hole - plug it */
409 memset(to, 0, n);
410 return n;
411}
412
413static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n)
414{
415 if (access_ok(VERIFY_WRITE, to, n))
416 n = __copy_to_user(to, from, n);
417 return n;
418}
419
420#define __copy_to_user_inatomic __copy_to_user
421#define __copy_from_user_inatomic __copy_from_user
422
423static inline unsigned long __must_check clear_user(void __user *to, unsigned long n)
424{
425 if (access_ok(VERIFY_WRITE, to, n))
426 n = __clear_user(to, n);
427 return n;
428}
429
430static inline long __must_check strncpy_from_user(char *dst, const char __user *src, long count)
431{
432 long res = -EFAULT;
433 if (access_ok(VERIFY_READ, src, 1))
434 res = __strncpy_from_user(dst, src, count);
435 return res;
436}
437
438#define strlen_user(s) strnlen_user(s, ~0UL >> 1)
439
440static inline long __must_check strnlen_user(const char __user *s, long n)
441{
442 unsigned long res = 0;
443
444 if (__addr_ok(s))
445 res = __strnlen_user(s, n);
446
447 return res;
448}
449
450#endif /* _ASMARM_UACCESS_H */
1/*
2 * arch/arm/include/asm/uaccess.h
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 */
8#ifndef _ASMARM_UACCESS_H
9#define _ASMARM_UACCESS_H
10
11/*
12 * User space memory access functions
13 */
14#include <linux/string.h>
15#include <asm/memory.h>
16#include <asm/domain.h>
17#include <asm/unified.h>
18#include <asm/compiler.h>
19
20#include <asm/extable.h>
21
22/*
23 * These two functions allow hooking accesses to userspace to increase
24 * system integrity by ensuring that the kernel can not inadvertantly
25 * perform such accesses (eg, via list poison values) which could then
26 * be exploited for priviledge escalation.
27 */
28static inline unsigned int uaccess_save_and_enable(void)
29{
30#ifdef CONFIG_CPU_SW_DOMAIN_PAN
31 unsigned int old_domain = get_domain();
32
33 /* Set the current domain access to permit user accesses */
34 set_domain((old_domain & ~domain_mask(DOMAIN_USER)) |
35 domain_val(DOMAIN_USER, DOMAIN_CLIENT));
36
37 return old_domain;
38#else
39 return 0;
40#endif
41}
42
43static inline void uaccess_restore(unsigned int flags)
44{
45#ifdef CONFIG_CPU_SW_DOMAIN_PAN
46 /* Restore the user access mask */
47 set_domain(flags);
48#endif
49}
50
51/*
52 * These two are intentionally not defined anywhere - if the kernel
53 * code generates any references to them, that's a bug.
54 */
55extern int __get_user_bad(void);
56extern int __put_user_bad(void);
57
58/*
59 * Note that this is actually 0x1,0000,0000
60 */
61#define KERNEL_DS 0x00000000
62#define get_ds() (KERNEL_DS)
63
64#ifdef CONFIG_MMU
65
66#define USER_DS TASK_SIZE
67#define get_fs() (current_thread_info()->addr_limit)
68
69static inline void set_fs(mm_segment_t fs)
70{
71 current_thread_info()->addr_limit = fs;
72 modify_domain(DOMAIN_KERNEL, fs ? DOMAIN_CLIENT : DOMAIN_MANAGER);
73}
74
75#define segment_eq(a, b) ((a) == (b))
76
77/* We use 33-bit arithmetic here... */
78#define __range_ok(addr, size) ({ \
79 unsigned long flag, roksum; \
80 __chk_user_ptr(addr); \
81 __asm__("adds %1, %2, %3; sbcccs %1, %1, %0; movcc %0, #0" \
82 : "=&r" (flag), "=&r" (roksum) \
83 : "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit) \
84 : "cc"); \
85 flag; })
86
87/*
88 * Single-value transfer routines. They automatically use the right
89 * size if we just have the right pointer type. Note that the functions
90 * which read from user space (*get_*) need to take care not to leak
91 * kernel data even if the calling code is buggy and fails to check
92 * the return value. This means zeroing out the destination variable
93 * or buffer on error. Normally this is done out of line by the
94 * fixup code, but there are a few places where it intrudes on the
95 * main code path. When we only write to user space, there is no
96 * problem.
97 */
98extern int __get_user_1(void *);
99extern int __get_user_2(void *);
100extern int __get_user_4(void *);
101extern int __get_user_32t_8(void *);
102extern int __get_user_8(void *);
103extern int __get_user_64t_1(void *);
104extern int __get_user_64t_2(void *);
105extern int __get_user_64t_4(void *);
106
107#define __GUP_CLOBBER_1 "lr", "cc"
108#ifdef CONFIG_CPU_USE_DOMAINS
109#define __GUP_CLOBBER_2 "ip", "lr", "cc"
110#else
111#define __GUP_CLOBBER_2 "lr", "cc"
112#endif
113#define __GUP_CLOBBER_4 "lr", "cc"
114#define __GUP_CLOBBER_32t_8 "lr", "cc"
115#define __GUP_CLOBBER_8 "lr", "cc"
116
117#define __get_user_x(__r2, __p, __e, __l, __s) \
118 __asm__ __volatile__ ( \
119 __asmeq("%0", "r0") __asmeq("%1", "r2") \
120 __asmeq("%3", "r1") \
121 "bl __get_user_" #__s \
122 : "=&r" (__e), "=r" (__r2) \
123 : "0" (__p), "r" (__l) \
124 : __GUP_CLOBBER_##__s)
125
126/* narrowing a double-word get into a single 32bit word register: */
127#ifdef __ARMEB__
128#define __get_user_x_32t(__r2, __p, __e, __l, __s) \
129 __get_user_x(__r2, __p, __e, __l, 32t_8)
130#else
131#define __get_user_x_32t __get_user_x
132#endif
133
134/*
135 * storing result into proper least significant word of 64bit target var,
136 * different only for big endian case where 64 bit __r2 lsw is r3:
137 */
138#ifdef __ARMEB__
139#define __get_user_x_64t(__r2, __p, __e, __l, __s) \
140 __asm__ __volatile__ ( \
141 __asmeq("%0", "r0") __asmeq("%1", "r2") \
142 __asmeq("%3", "r1") \
143 "bl __get_user_64t_" #__s \
144 : "=&r" (__e), "=r" (__r2) \
145 : "0" (__p), "r" (__l) \
146 : __GUP_CLOBBER_##__s)
147#else
148#define __get_user_x_64t __get_user_x
149#endif
150
151
152#define __get_user_check(x, p) \
153 ({ \
154 unsigned long __limit = current_thread_info()->addr_limit - 1; \
155 register const typeof(*(p)) __user *__p asm("r0") = (p);\
156 register typeof(x) __r2 asm("r2"); \
157 register unsigned long __l asm("r1") = __limit; \
158 register int __e asm("r0"); \
159 unsigned int __ua_flags = uaccess_save_and_enable(); \
160 switch (sizeof(*(__p))) { \
161 case 1: \
162 if (sizeof((x)) >= 8) \
163 __get_user_x_64t(__r2, __p, __e, __l, 1); \
164 else \
165 __get_user_x(__r2, __p, __e, __l, 1); \
166 break; \
167 case 2: \
168 if (sizeof((x)) >= 8) \
169 __get_user_x_64t(__r2, __p, __e, __l, 2); \
170 else \
171 __get_user_x(__r2, __p, __e, __l, 2); \
172 break; \
173 case 4: \
174 if (sizeof((x)) >= 8) \
175 __get_user_x_64t(__r2, __p, __e, __l, 4); \
176 else \
177 __get_user_x(__r2, __p, __e, __l, 4); \
178 break; \
179 case 8: \
180 if (sizeof((x)) < 8) \
181 __get_user_x_32t(__r2, __p, __e, __l, 4); \
182 else \
183 __get_user_x(__r2, __p, __e, __l, 8); \
184 break; \
185 default: __e = __get_user_bad(); break; \
186 } \
187 uaccess_restore(__ua_flags); \
188 x = (typeof(*(p))) __r2; \
189 __e; \
190 })
191
192#define get_user(x, p) \
193 ({ \
194 might_fault(); \
195 __get_user_check(x, p); \
196 })
197
198extern int __put_user_1(void *, unsigned int);
199extern int __put_user_2(void *, unsigned int);
200extern int __put_user_4(void *, unsigned int);
201extern int __put_user_8(void *, unsigned long long);
202
203#define __put_user_check(__pu_val, __ptr, __err, __s) \
204 ({ \
205 unsigned long __limit = current_thread_info()->addr_limit - 1; \
206 register typeof(__pu_val) __r2 asm("r2") = __pu_val; \
207 register const void __user *__p asm("r0") = __ptr; \
208 register unsigned long __l asm("r1") = __limit; \
209 register int __e asm("r0"); \
210 __asm__ __volatile__ ( \
211 __asmeq("%0", "r0") __asmeq("%2", "r2") \
212 __asmeq("%3", "r1") \
213 "bl __put_user_" #__s \
214 : "=&r" (__e) \
215 : "0" (__p), "r" (__r2), "r" (__l) \
216 : "ip", "lr", "cc"); \
217 __err = __e; \
218 })
219
220#else /* CONFIG_MMU */
221
222/*
223 * uClinux has only one addr space, so has simplified address limits.
224 */
225#define USER_DS KERNEL_DS
226
227#define segment_eq(a, b) (1)
228#define __addr_ok(addr) ((void)(addr), 1)
229#define __range_ok(addr, size) ((void)(addr), 0)
230#define get_fs() (KERNEL_DS)
231
232static inline void set_fs(mm_segment_t fs)
233{
234}
235
236#define get_user(x, p) __get_user(x, p)
237#define __put_user_check __put_user_nocheck
238
239#endif /* CONFIG_MMU */
240
241#define access_ok(type, addr, size) (__range_ok(addr, size) == 0)
242
243#define user_addr_max() \
244 (uaccess_kernel() ? ~0UL : get_fs())
245
246/*
247 * The "__xxx" versions of the user access functions do not verify the
248 * address space - it must have been done previously with a separate
249 * "access_ok()" call.
250 *
251 * The "xxx_error" versions set the third argument to EFAULT if an
252 * error occurs, and leave it unchanged on success. Note that these
253 * versions are void (ie, don't return a value as such).
254 */
255#define __get_user(x, ptr) \
256({ \
257 long __gu_err = 0; \
258 __get_user_err((x), (ptr), __gu_err); \
259 __gu_err; \
260})
261
262#define __get_user_error(x, ptr, err) \
263({ \
264 __get_user_err((x), (ptr), err); \
265 (void) 0; \
266})
267
268#define __get_user_err(x, ptr, err) \
269do { \
270 unsigned long __gu_addr = (unsigned long)(ptr); \
271 unsigned long __gu_val; \
272 unsigned int __ua_flags; \
273 __chk_user_ptr(ptr); \
274 might_fault(); \
275 __ua_flags = uaccess_save_and_enable(); \
276 switch (sizeof(*(ptr))) { \
277 case 1: __get_user_asm_byte(__gu_val, __gu_addr, err); break; \
278 case 2: __get_user_asm_half(__gu_val, __gu_addr, err); break; \
279 case 4: __get_user_asm_word(__gu_val, __gu_addr, err); break; \
280 default: (__gu_val) = __get_user_bad(); \
281 } \
282 uaccess_restore(__ua_flags); \
283 (x) = (__typeof__(*(ptr)))__gu_val; \
284} while (0)
285
286#define __get_user_asm(x, addr, err, instr) \
287 __asm__ __volatile__( \
288 "1: " TUSER(instr) " %1, [%2], #0\n" \
289 "2:\n" \
290 " .pushsection .text.fixup,\"ax\"\n" \
291 " .align 2\n" \
292 "3: mov %0, %3\n" \
293 " mov %1, #0\n" \
294 " b 2b\n" \
295 " .popsection\n" \
296 " .pushsection __ex_table,\"a\"\n" \
297 " .align 3\n" \
298 " .long 1b, 3b\n" \
299 " .popsection" \
300 : "+r" (err), "=&r" (x) \
301 : "r" (addr), "i" (-EFAULT) \
302 : "cc")
303
304#define __get_user_asm_byte(x, addr, err) \
305 __get_user_asm(x, addr, err, ldrb)
306
307#ifndef __ARMEB__
308#define __get_user_asm_half(x, __gu_addr, err) \
309({ \
310 unsigned long __b1, __b2; \
311 __get_user_asm_byte(__b1, __gu_addr, err); \
312 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
313 (x) = __b1 | (__b2 << 8); \
314})
315#else
316#define __get_user_asm_half(x, __gu_addr, err) \
317({ \
318 unsigned long __b1, __b2; \
319 __get_user_asm_byte(__b1, __gu_addr, err); \
320 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
321 (x) = (__b1 << 8) | __b2; \
322})
323#endif
324
325#define __get_user_asm_word(x, addr, err) \
326 __get_user_asm(x, addr, err, ldr)
327
328
329#define __put_user_switch(x, ptr, __err, __fn) \
330 do { \
331 const __typeof__(*(ptr)) __user *__pu_ptr = (ptr); \
332 __typeof__(*(ptr)) __pu_val = (x); \
333 unsigned int __ua_flags; \
334 might_fault(); \
335 __ua_flags = uaccess_save_and_enable(); \
336 switch (sizeof(*(ptr))) { \
337 case 1: __fn(__pu_val, __pu_ptr, __err, 1); break; \
338 case 2: __fn(__pu_val, __pu_ptr, __err, 2); break; \
339 case 4: __fn(__pu_val, __pu_ptr, __err, 4); break; \
340 case 8: __fn(__pu_val, __pu_ptr, __err, 8); break; \
341 default: __err = __put_user_bad(); break; \
342 } \
343 uaccess_restore(__ua_flags); \
344 } while (0)
345
346#define put_user(x, ptr) \
347({ \
348 int __pu_err = 0; \
349 __put_user_switch((x), (ptr), __pu_err, __put_user_check); \
350 __pu_err; \
351})
352
353#define __put_user(x, ptr) \
354({ \
355 long __pu_err = 0; \
356 __put_user_switch((x), (ptr), __pu_err, __put_user_nocheck); \
357 __pu_err; \
358})
359
360#define __put_user_error(x, ptr, err) \
361({ \
362 __put_user_switch((x), (ptr), (err), __put_user_nocheck); \
363 (void) 0; \
364})
365
366#define __put_user_nocheck(x, __pu_ptr, __err, __size) \
367 do { \
368 unsigned long __pu_addr = (unsigned long)__pu_ptr; \
369 __put_user_nocheck_##__size(x, __pu_addr, __err); \
370 } while (0)
371
372#define __put_user_nocheck_1 __put_user_asm_byte
373#define __put_user_nocheck_2 __put_user_asm_half
374#define __put_user_nocheck_4 __put_user_asm_word
375#define __put_user_nocheck_8 __put_user_asm_dword
376
377#define __put_user_asm(x, __pu_addr, err, instr) \
378 __asm__ __volatile__( \
379 "1: " TUSER(instr) " %1, [%2], #0\n" \
380 "2:\n" \
381 " .pushsection .text.fixup,\"ax\"\n" \
382 " .align 2\n" \
383 "3: mov %0, %3\n" \
384 " b 2b\n" \
385 " .popsection\n" \
386 " .pushsection __ex_table,\"a\"\n" \
387 " .align 3\n" \
388 " .long 1b, 3b\n" \
389 " .popsection" \
390 : "+r" (err) \
391 : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
392 : "cc")
393
394#define __put_user_asm_byte(x, __pu_addr, err) \
395 __put_user_asm(x, __pu_addr, err, strb)
396
397#ifndef __ARMEB__
398#define __put_user_asm_half(x, __pu_addr, err) \
399({ \
400 unsigned long __temp = (__force unsigned long)(x); \
401 __put_user_asm_byte(__temp, __pu_addr, err); \
402 __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \
403})
404#else
405#define __put_user_asm_half(x, __pu_addr, err) \
406({ \
407 unsigned long __temp = (__force unsigned long)(x); \
408 __put_user_asm_byte(__temp >> 8, __pu_addr, err); \
409 __put_user_asm_byte(__temp, __pu_addr + 1, err); \
410})
411#endif
412
413#define __put_user_asm_word(x, __pu_addr, err) \
414 __put_user_asm(x, __pu_addr, err, str)
415
416#ifndef __ARMEB__
417#define __reg_oper0 "%R2"
418#define __reg_oper1 "%Q2"
419#else
420#define __reg_oper0 "%Q2"
421#define __reg_oper1 "%R2"
422#endif
423
424#define __put_user_asm_dword(x, __pu_addr, err) \
425 __asm__ __volatile__( \
426 ARM( "1: " TUSER(str) " " __reg_oper1 ", [%1], #4\n" ) \
427 ARM( "2: " TUSER(str) " " __reg_oper0 ", [%1]\n" ) \
428 THUMB( "1: " TUSER(str) " " __reg_oper1 ", [%1]\n" ) \
429 THUMB( "2: " TUSER(str) " " __reg_oper0 ", [%1, #4]\n" ) \
430 "3:\n" \
431 " .pushsection .text.fixup,\"ax\"\n" \
432 " .align 2\n" \
433 "4: mov %0, %3\n" \
434 " b 3b\n" \
435 " .popsection\n" \
436 " .pushsection __ex_table,\"a\"\n" \
437 " .align 3\n" \
438 " .long 1b, 4b\n" \
439 " .long 2b, 4b\n" \
440 " .popsection" \
441 : "+r" (err), "+r" (__pu_addr) \
442 : "r" (x), "i" (-EFAULT) \
443 : "cc")
444
445
446#ifdef CONFIG_MMU
447extern unsigned long __must_check
448arm_copy_from_user(void *to, const void __user *from, unsigned long n);
449
450static inline unsigned long __must_check
451raw_copy_from_user(void *to, const void __user *from, unsigned long n)
452{
453 unsigned int __ua_flags;
454
455 __ua_flags = uaccess_save_and_enable();
456 n = arm_copy_from_user(to, from, n);
457 uaccess_restore(__ua_flags);
458 return n;
459}
460
461extern unsigned long __must_check
462arm_copy_to_user(void __user *to, const void *from, unsigned long n);
463extern unsigned long __must_check
464__copy_to_user_std(void __user *to, const void *from, unsigned long n);
465
466static inline unsigned long __must_check
467raw_copy_to_user(void __user *to, const void *from, unsigned long n)
468{
469#ifndef CONFIG_UACCESS_WITH_MEMCPY
470 unsigned int __ua_flags;
471 __ua_flags = uaccess_save_and_enable();
472 n = arm_copy_to_user(to, from, n);
473 uaccess_restore(__ua_flags);
474 return n;
475#else
476 return arm_copy_to_user(to, from, n);
477#endif
478}
479
480extern unsigned long __must_check
481arm_clear_user(void __user *addr, unsigned long n);
482extern unsigned long __must_check
483__clear_user_std(void __user *addr, unsigned long n);
484
485static inline unsigned long __must_check
486__clear_user(void __user *addr, unsigned long n)
487{
488 unsigned int __ua_flags = uaccess_save_and_enable();
489 n = arm_clear_user(addr, n);
490 uaccess_restore(__ua_flags);
491 return n;
492}
493
494#else
495static inline unsigned long
496raw_copy_from_user(void *to, const void __user *from, unsigned long n)
497{
498 memcpy(to, (const void __force *)from, n);
499 return 0;
500}
501static inline unsigned long
502raw_copy_to_user(void __user *to, const void *from, unsigned long n)
503{
504 memcpy((void __force *)to, from, n);
505 return 0;
506}
507#define __clear_user(addr, n) (memset((void __force *)addr, 0, n), 0)
508#endif
509#define INLINE_COPY_TO_USER
510#define INLINE_COPY_FROM_USER
511
512static inline unsigned long __must_check clear_user(void __user *to, unsigned long n)
513{
514 if (access_ok(VERIFY_WRITE, to, n))
515 n = __clear_user(to, n);
516 return n;
517}
518
519/* These are from lib/ code, and use __get_user() and friends */
520extern long strncpy_from_user(char *dest, const char __user *src, long count);
521
522extern __must_check long strnlen_user(const char __user *str, long n);
523
524#endif /* _ASMARM_UACCESS_H */