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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/unified.h>
20#include <asm/compiler.h>
21
22#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
23#include <asm-generic/uaccess-unaligned.h>
24#else
25#define __get_user_unaligned __get_user
26#define __put_user_unaligned __put_user
27#endif
28
29#define VERIFY_READ 0
30#define VERIFY_WRITE 1
31
32/*
33 * The exception table consists of pairs of addresses: the first is the
34 * address of an instruction that is allowed to fault, and the second is
35 * the address at which the program should continue. No registers are
36 * modified, so it is entirely up to the continuation code to figure out
37 * what to do.
38 *
39 * All the routines below use bits of fixup code that are out of line
40 * with the main instruction path. This means when everything is well,
41 * we don't even have to jump over them. Further, they do not intrude
42 * on our cache or tlb entries.
43 */
44
45struct exception_table_entry
46{
47 unsigned long insn, fixup;
48};
49
50extern int fixup_exception(struct pt_regs *regs);
51
52/*
53 * These two functions allow hooking accesses to userspace to increase
54 * system integrity by ensuring that the kernel can not inadvertantly
55 * perform such accesses (eg, via list poison values) which could then
56 * be exploited for priviledge escalation.
57 */
58static inline unsigned int uaccess_save_and_enable(void)
59{
60#ifdef CONFIG_CPU_SW_DOMAIN_PAN
61 unsigned int old_domain = get_domain();
62
63 /* Set the current domain access to permit user accesses */
64 set_domain((old_domain & ~domain_mask(DOMAIN_USER)) |
65 domain_val(DOMAIN_USER, DOMAIN_CLIENT));
66
67 return old_domain;
68#else
69 return 0;
70#endif
71}
72
73static inline void uaccess_restore(unsigned int flags)
74{
75#ifdef CONFIG_CPU_SW_DOMAIN_PAN
76 /* Restore the user access mask */
77 set_domain(flags);
78#endif
79}
80
81/*
82 * These two are intentionally not defined anywhere - if the kernel
83 * code generates any references to them, that's a bug.
84 */
85extern int __get_user_bad(void);
86extern int __put_user_bad(void);
87
88/*
89 * Note that this is actually 0x1,0000,0000
90 */
91#define KERNEL_DS 0x00000000
92#define get_ds() (KERNEL_DS)
93
94#ifdef CONFIG_MMU
95
96#define USER_DS TASK_SIZE
97#define get_fs() (current_thread_info()->addr_limit)
98
99static inline void set_fs(mm_segment_t fs)
100{
101 current_thread_info()->addr_limit = fs;
102 modify_domain(DOMAIN_KERNEL, fs ? DOMAIN_CLIENT : DOMAIN_MANAGER);
103}
104
105#define segment_eq(a, b) ((a) == (b))
106
107/* We use 33-bit arithmetic here... */
108#define __range_ok(addr, size) ({ \
109 unsigned long flag, roksum; \
110 __chk_user_ptr(addr); \
111 __asm__("adds %1, %2, %3; sbcccs %1, %1, %0; movcc %0, #0" \
112 : "=&r" (flag), "=&r" (roksum) \
113 : "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit) \
114 : "cc"); \
115 flag; })
116
117/*
118 * Single-value transfer routines. They automatically use the right
119 * size if we just have the right pointer type. Note that the functions
120 * which read from user space (*get_*) need to take care not to leak
121 * kernel data even if the calling code is buggy and fails to check
122 * the return value. This means zeroing out the destination variable
123 * or buffer on error. Normally this is done out of line by the
124 * fixup code, but there are a few places where it intrudes on the
125 * main code path. When we only write to user space, there is no
126 * problem.
127 */
128extern int __get_user_1(void *);
129extern int __get_user_2(void *);
130extern int __get_user_4(void *);
131extern int __get_user_32t_8(void *);
132extern int __get_user_8(void *);
133extern int __get_user_64t_1(void *);
134extern int __get_user_64t_2(void *);
135extern int __get_user_64t_4(void *);
136
137#define __GUP_CLOBBER_1 "lr", "cc"
138#ifdef CONFIG_CPU_USE_DOMAINS
139#define __GUP_CLOBBER_2 "ip", "lr", "cc"
140#else
141#define __GUP_CLOBBER_2 "lr", "cc"
142#endif
143#define __GUP_CLOBBER_4 "lr", "cc"
144#define __GUP_CLOBBER_32t_8 "lr", "cc"
145#define __GUP_CLOBBER_8 "lr", "cc"
146
147#define __get_user_x(__r2, __p, __e, __l, __s) \
148 __asm__ __volatile__ ( \
149 __asmeq("%0", "r0") __asmeq("%1", "r2") \
150 __asmeq("%3", "r1") \
151 "bl __get_user_" #__s \
152 : "=&r" (__e), "=r" (__r2) \
153 : "0" (__p), "r" (__l) \
154 : __GUP_CLOBBER_##__s)
155
156/* narrowing a double-word get into a single 32bit word register: */
157#ifdef __ARMEB__
158#define __get_user_x_32t(__r2, __p, __e, __l, __s) \
159 __get_user_x(__r2, __p, __e, __l, 32t_8)
160#else
161#define __get_user_x_32t __get_user_x
162#endif
163
164/*
165 * storing result into proper least significant word of 64bit target var,
166 * different only for big endian case where 64 bit __r2 lsw is r3:
167 */
168#ifdef __ARMEB__
169#define __get_user_x_64t(__r2, __p, __e, __l, __s) \
170 __asm__ __volatile__ ( \
171 __asmeq("%0", "r0") __asmeq("%1", "r2") \
172 __asmeq("%3", "r1") \
173 "bl __get_user_64t_" #__s \
174 : "=&r" (__e), "=r" (__r2) \
175 : "0" (__p), "r" (__l) \
176 : __GUP_CLOBBER_##__s)
177#else
178#define __get_user_x_64t __get_user_x
179#endif
180
181
182#define __get_user_check(x, p) \
183 ({ \
184 unsigned long __limit = current_thread_info()->addr_limit - 1; \
185 register const typeof(*(p)) __user *__p asm("r0") = (p);\
186 register typeof(x) __r2 asm("r2"); \
187 register unsigned long __l asm("r1") = __limit; \
188 register int __e asm("r0"); \
189 unsigned int __ua_flags = uaccess_save_and_enable(); \
190 switch (sizeof(*(__p))) { \
191 case 1: \
192 if (sizeof((x)) >= 8) \
193 __get_user_x_64t(__r2, __p, __e, __l, 1); \
194 else \
195 __get_user_x(__r2, __p, __e, __l, 1); \
196 break; \
197 case 2: \
198 if (sizeof((x)) >= 8) \
199 __get_user_x_64t(__r2, __p, __e, __l, 2); \
200 else \
201 __get_user_x(__r2, __p, __e, __l, 2); \
202 break; \
203 case 4: \
204 if (sizeof((x)) >= 8) \
205 __get_user_x_64t(__r2, __p, __e, __l, 4); \
206 else \
207 __get_user_x(__r2, __p, __e, __l, 4); \
208 break; \
209 case 8: \
210 if (sizeof((x)) < 8) \
211 __get_user_x_32t(__r2, __p, __e, __l, 4); \
212 else \
213 __get_user_x(__r2, __p, __e, __l, 8); \
214 break; \
215 default: __e = __get_user_bad(); break; \
216 } \
217 uaccess_restore(__ua_flags); \
218 x = (typeof(*(p))) __r2; \
219 __e; \
220 })
221
222#define get_user(x, p) \
223 ({ \
224 might_fault(); \
225 __get_user_check(x, p); \
226 })
227
228extern int __put_user_1(void *, unsigned int);
229extern int __put_user_2(void *, unsigned int);
230extern int __put_user_4(void *, unsigned int);
231extern int __put_user_8(void *, unsigned long long);
232
233#define __put_user_check(__pu_val, __ptr, __err, __s) \
234 ({ \
235 unsigned long __limit = current_thread_info()->addr_limit - 1; \
236 register typeof(__pu_val) __r2 asm("r2") = __pu_val; \
237 register const void __user *__p asm("r0") = __ptr; \
238 register unsigned long __l asm("r1") = __limit; \
239 register int __e asm("r0"); \
240 __asm__ __volatile__ ( \
241 __asmeq("%0", "r0") __asmeq("%2", "r2") \
242 __asmeq("%3", "r1") \
243 "bl __put_user_" #__s \
244 : "=&r" (__e) \
245 : "0" (__p), "r" (__r2), "r" (__l) \
246 : "ip", "lr", "cc"); \
247 __err = __e; \
248 })
249
250#else /* CONFIG_MMU */
251
252/*
253 * uClinux has only one addr space, so has simplified address limits.
254 */
255#define USER_DS KERNEL_DS
256
257#define segment_eq(a, b) (1)
258#define __addr_ok(addr) ((void)(addr), 1)
259#define __range_ok(addr, size) ((void)(addr), 0)
260#define get_fs() (KERNEL_DS)
261
262static inline void set_fs(mm_segment_t fs)
263{
264}
265
266#define get_user(x, p) __get_user(x, p)
267#define __put_user_check __put_user_nocheck
268
269#endif /* CONFIG_MMU */
270
271#define access_ok(type, addr, size) (__range_ok(addr, size) == 0)
272
273#define user_addr_max() \
274 (segment_eq(get_fs(), KERNEL_DS) ? ~0UL : get_fs())
275
276/*
277 * The "__xxx" versions of the user access functions do not verify the
278 * address space - it must have been done previously with a separate
279 * "access_ok()" call.
280 *
281 * The "xxx_error" versions set the third argument to EFAULT if an
282 * error occurs, and leave it unchanged on success. Note that these
283 * versions are void (ie, don't return a value as such).
284 */
285#define __get_user(x, ptr) \
286({ \
287 long __gu_err = 0; \
288 __get_user_err((x), (ptr), __gu_err); \
289 __gu_err; \
290})
291
292#define __get_user_error(x, ptr, err) \
293({ \
294 __get_user_err((x), (ptr), err); \
295 (void) 0; \
296})
297
298#define __get_user_err(x, ptr, err) \
299do { \
300 unsigned long __gu_addr = (unsigned long)(ptr); \
301 unsigned long __gu_val; \
302 unsigned int __ua_flags; \
303 __chk_user_ptr(ptr); \
304 might_fault(); \
305 __ua_flags = uaccess_save_and_enable(); \
306 switch (sizeof(*(ptr))) { \
307 case 1: __get_user_asm_byte(__gu_val, __gu_addr, err); break; \
308 case 2: __get_user_asm_half(__gu_val, __gu_addr, err); break; \
309 case 4: __get_user_asm_word(__gu_val, __gu_addr, err); break; \
310 default: (__gu_val) = __get_user_bad(); \
311 } \
312 uaccess_restore(__ua_flags); \
313 (x) = (__typeof__(*(ptr)))__gu_val; \
314} while (0)
315
316#define __get_user_asm(x, addr, err, instr) \
317 __asm__ __volatile__( \
318 "1: " TUSER(instr) " %1, [%2], #0\n" \
319 "2:\n" \
320 " .pushsection .text.fixup,\"ax\"\n" \
321 " .align 2\n" \
322 "3: mov %0, %3\n" \
323 " mov %1, #0\n" \
324 " b 2b\n" \
325 " .popsection\n" \
326 " .pushsection __ex_table,\"a\"\n" \
327 " .align 3\n" \
328 " .long 1b, 3b\n" \
329 " .popsection" \
330 : "+r" (err), "=&r" (x) \
331 : "r" (addr), "i" (-EFAULT) \
332 : "cc")
333
334#define __get_user_asm_byte(x, addr, err) \
335 __get_user_asm(x, addr, err, ldrb)
336
337#ifndef __ARMEB__
338#define __get_user_asm_half(x, __gu_addr, err) \
339({ \
340 unsigned long __b1, __b2; \
341 __get_user_asm_byte(__b1, __gu_addr, err); \
342 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
343 (x) = __b1 | (__b2 << 8); \
344})
345#else
346#define __get_user_asm_half(x, __gu_addr, err) \
347({ \
348 unsigned long __b1, __b2; \
349 __get_user_asm_byte(__b1, __gu_addr, err); \
350 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
351 (x) = (__b1 << 8) | __b2; \
352})
353#endif
354
355#define __get_user_asm_word(x, addr, err) \
356 __get_user_asm(x, addr, err, ldr)
357
358
359#define __put_user_switch(x, ptr, __err, __fn) \
360 do { \
361 const __typeof__(*(ptr)) __user *__pu_ptr = (ptr); \
362 __typeof__(*(ptr)) __pu_val = (x); \
363 unsigned int __ua_flags; \
364 might_fault(); \
365 __ua_flags = uaccess_save_and_enable(); \
366 switch (sizeof(*(ptr))) { \
367 case 1: __fn(__pu_val, __pu_ptr, __err, 1); break; \
368 case 2: __fn(__pu_val, __pu_ptr, __err, 2); break; \
369 case 4: __fn(__pu_val, __pu_ptr, __err, 4); break; \
370 case 8: __fn(__pu_val, __pu_ptr, __err, 8); break; \
371 default: __err = __put_user_bad(); break; \
372 } \
373 uaccess_restore(__ua_flags); \
374 } while (0)
375
376#define put_user(x, ptr) \
377({ \
378 int __pu_err = 0; \
379 __put_user_switch((x), (ptr), __pu_err, __put_user_check); \
380 __pu_err; \
381})
382
383#define __put_user(x, ptr) \
384({ \
385 long __pu_err = 0; \
386 __put_user_switch((x), (ptr), __pu_err, __put_user_nocheck); \
387 __pu_err; \
388})
389
390#define __put_user_error(x, ptr, err) \
391({ \
392 __put_user_switch((x), (ptr), (err), __put_user_nocheck); \
393 (void) 0; \
394})
395
396#define __put_user_nocheck(x, __pu_ptr, __err, __size) \
397 do { \
398 unsigned long __pu_addr = (unsigned long)__pu_ptr; \
399 __put_user_nocheck_##__size(x, __pu_addr, __err); \
400 } while (0)
401
402#define __put_user_nocheck_1 __put_user_asm_byte
403#define __put_user_nocheck_2 __put_user_asm_half
404#define __put_user_nocheck_4 __put_user_asm_word
405#define __put_user_nocheck_8 __put_user_asm_dword
406
407#define __put_user_asm(x, __pu_addr, err, instr) \
408 __asm__ __volatile__( \
409 "1: " TUSER(instr) " %1, [%2], #0\n" \
410 "2:\n" \
411 " .pushsection .text.fixup,\"ax\"\n" \
412 " .align 2\n" \
413 "3: mov %0, %3\n" \
414 " b 2b\n" \
415 " .popsection\n" \
416 " .pushsection __ex_table,\"a\"\n" \
417 " .align 3\n" \
418 " .long 1b, 3b\n" \
419 " .popsection" \
420 : "+r" (err) \
421 : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
422 : "cc")
423
424#define __put_user_asm_byte(x, __pu_addr, err) \
425 __put_user_asm(x, __pu_addr, err, strb)
426
427#ifndef __ARMEB__
428#define __put_user_asm_half(x, __pu_addr, err) \
429({ \
430 unsigned long __temp = (__force unsigned long)(x); \
431 __put_user_asm_byte(__temp, __pu_addr, err); \
432 __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \
433})
434#else
435#define __put_user_asm_half(x, __pu_addr, err) \
436({ \
437 unsigned long __temp = (__force unsigned long)(x); \
438 __put_user_asm_byte(__temp >> 8, __pu_addr, err); \
439 __put_user_asm_byte(__temp, __pu_addr + 1, err); \
440})
441#endif
442
443#define __put_user_asm_word(x, __pu_addr, err) \
444 __put_user_asm(x, __pu_addr, err, str)
445
446#ifndef __ARMEB__
447#define __reg_oper0 "%R2"
448#define __reg_oper1 "%Q2"
449#else
450#define __reg_oper0 "%Q2"
451#define __reg_oper1 "%R2"
452#endif
453
454#define __put_user_asm_dword(x, __pu_addr, err) \
455 __asm__ __volatile__( \
456 ARM( "1: " TUSER(str) " " __reg_oper1 ", [%1], #4\n" ) \
457 ARM( "2: " TUSER(str) " " __reg_oper0 ", [%1]\n" ) \
458 THUMB( "1: " TUSER(str) " " __reg_oper1 ", [%1]\n" ) \
459 THUMB( "2: " TUSER(str) " " __reg_oper0 ", [%1, #4]\n" ) \
460 "3:\n" \
461 " .pushsection .text.fixup,\"ax\"\n" \
462 " .align 2\n" \
463 "4: mov %0, %3\n" \
464 " b 3b\n" \
465 " .popsection\n" \
466 " .pushsection __ex_table,\"a\"\n" \
467 " .align 3\n" \
468 " .long 1b, 4b\n" \
469 " .long 2b, 4b\n" \
470 " .popsection" \
471 : "+r" (err), "+r" (__pu_addr) \
472 : "r" (x), "i" (-EFAULT) \
473 : "cc")
474
475
476#ifdef CONFIG_MMU
477extern unsigned long __must_check
478arm_copy_from_user(void *to, const void __user *from, unsigned long n);
479
480static inline unsigned long __must_check
481__arch_copy_from_user(void *to, const void __user *from, unsigned long n)
482{
483 unsigned int __ua_flags;
484
485 __ua_flags = uaccess_save_and_enable();
486 n = arm_copy_from_user(to, from, n);
487 uaccess_restore(__ua_flags);
488 return n;
489}
490
491extern unsigned long __must_check
492arm_copy_to_user(void __user *to, const void *from, unsigned long n);
493extern unsigned long __must_check
494__copy_to_user_std(void __user *to, const void *from, unsigned long n);
495
496static inline unsigned long __must_check
497__arch_copy_to_user(void __user *to, const void *from, unsigned long n)
498{
499#ifndef CONFIG_UACCESS_WITH_MEMCPY
500 unsigned int __ua_flags;
501 __ua_flags = uaccess_save_and_enable();
502 n = arm_copy_to_user(to, from, n);
503 uaccess_restore(__ua_flags);
504 return n;
505#else
506 return arm_copy_to_user(to, from, n);
507#endif
508}
509
510extern unsigned long __must_check
511arm_clear_user(void __user *addr, unsigned long n);
512extern unsigned long __must_check
513__clear_user_std(void __user *addr, unsigned long n);
514
515static inline unsigned long __must_check
516__clear_user(void __user *addr, unsigned long n)
517{
518 unsigned int __ua_flags = uaccess_save_and_enable();
519 n = arm_clear_user(addr, n);
520 uaccess_restore(__ua_flags);
521 return n;
522}
523
524#else
525#define __arch_copy_from_user(to, from, n) \
526 (memcpy(to, (void __force *)from, n), 0)
527#define __arch_copy_to_user(to, from, n) \
528 (memcpy((void __force *)to, from, n), 0)
529#define __clear_user(addr, n) (memset((void __force *)addr, 0, n), 0)
530#endif
531
532static inline unsigned long __must_check
533__copy_from_user(void *to, const void __user *from, unsigned long n)
534{
535 check_object_size(to, n, false);
536 return __arch_copy_from_user(to, from, n);
537}
538
539static inline unsigned long __must_check
540copy_from_user(void *to, const void __user *from, unsigned long n)
541{
542 unsigned long res = n;
543
544 check_object_size(to, n, false);
545
546 if (likely(access_ok(VERIFY_READ, from, n)))
547 res = __arch_copy_from_user(to, from, n);
548 if (unlikely(res))
549 memset(to + (n - res), 0, res);
550 return res;
551}
552
553static inline unsigned long __must_check
554__copy_to_user(void __user *to, const void *from, unsigned long n)
555{
556 check_object_size(from, n, true);
557
558 return __arch_copy_to_user(to, from, n);
559}
560
561static inline unsigned long __must_check
562copy_to_user(void __user *to, const void *from, unsigned long n)
563{
564 check_object_size(from, n, true);
565
566 if (access_ok(VERIFY_WRITE, to, n))
567 n = __arch_copy_to_user(to, from, n);
568 return n;
569}
570
571#define __copy_to_user_inatomic __copy_to_user
572#define __copy_from_user_inatomic __copy_from_user
573
574static inline unsigned long __must_check clear_user(void __user *to, unsigned long n)
575{
576 if (access_ok(VERIFY_WRITE, to, n))
577 n = __clear_user(to, n);
578 return n;
579}
580
581/* These are from lib/ code, and use __get_user() and friends */
582extern long strncpy_from_user(char *dest, const char __user *src, long count);
583
584extern __must_check long strlen_user(const char __user *str);
585extern __must_check long strnlen_user(const char __user *str, long n);
586
587#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 */