1
2
3
4
5#ifndef _ASMARM_UACCESS_H
6#define _ASMARM_UACCESS_H
7
8
9
10
11#include <linux/string.h>
12#include <asm/memory.h>
13#include <asm/domain.h>
14#include <asm/unified.h>
15#include <asm/compiler.h>
16
17#include <asm/extable.h>
18
19
20
21
22
23
24
25static __always_inline unsigned int uaccess_save_and_enable(void)
26{
27#ifdef CONFIG_CPU_SW_DOMAIN_PAN
28 unsigned int old_domain = get_domain();
29
30
31 set_domain((old_domain & ~domain_mask(DOMAIN_USER)) |
32 domain_val(DOMAIN_USER, DOMAIN_CLIENT));
33
34 return old_domain;
35#else
36 return 0;
37#endif
38}
39
40static __always_inline void uaccess_restore(unsigned int flags)
41{
42#ifdef CONFIG_CPU_SW_DOMAIN_PAN
43
44 set_domain(flags);
45#endif
46}
47
48
49
50
51
52extern int __get_user_bad(void);
53extern int __put_user_bad(void);
54
55
56
57
58#define KERNEL_DS 0x00000000
59
60#ifdef CONFIG_MMU
61
62#define USER_DS TASK_SIZE
63#define get_fs() (current_thread_info()->addr_limit)
64
65static inline void set_fs(mm_segment_t fs)
66{
67 current_thread_info()->addr_limit = fs;
68
69
70
71
72
73 dsb(nsh);
74 isb();
75
76 modify_domain(DOMAIN_KERNEL, fs ? DOMAIN_CLIENT : DOMAIN_MANAGER);
77}
78
79#define uaccess_kernel() (get_fs() == KERNEL_DS)
80
81
82
83
84
85
86#define __range_ok(addr, size) ({ \
87 unsigned long flag, roksum; \
88 __chk_user_ptr(addr); \
89 __asm__(".syntax unified\n" \
90 "adds %1, %2, %3; sbcscc %1, %1, %0; movcc %0, #0" \
91 : "=&r" (flag), "=&r" (roksum) \
92 : "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit) \
93 : "cc"); \
94 flag; })
95
96
97
98
99
100#define __inttype(x) \
101 __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL))
102
103
104
105
106
107#define uaccess_mask_range_ptr(ptr, size) \
108 ((__typeof__(ptr))__uaccess_mask_range_ptr(ptr, size))
109static inline void __user *__uaccess_mask_range_ptr(const void __user *ptr,
110 size_t size)
111{
112 void __user *safe_ptr = (void __user *)ptr;
113 unsigned long tmp;
114
115 asm volatile(
116 " .syntax unified\n"
117 " sub %1, %3, #1\n"
118 " subs %1, %1, %0\n"
119 " addhs %1, %1, #1\n"
120 " subshs %1, %1, %2\n"
121 " movlo %0, #0\n"
122 : "+r" (safe_ptr), "=&r" (tmp)
123 : "r" (size), "r" (current_thread_info()->addr_limit)
124 : "cc");
125
126 csdb();
127 return safe_ptr;
128}
129
130
131
132
133
134
135
136
137
138
139
140
141extern int __get_user_1(void *);
142extern int __get_user_2(void *);
143extern int __get_user_4(void *);
144extern int __get_user_32t_8(void *);
145extern int __get_user_8(void *);
146extern int __get_user_64t_1(void *);
147extern int __get_user_64t_2(void *);
148extern int __get_user_64t_4(void *);
149
150#define __GUP_CLOBBER_1 "lr", "cc"
151#ifdef CONFIG_CPU_USE_DOMAINS
152#define __GUP_CLOBBER_2 "ip", "lr", "cc"
153#else
154#define __GUP_CLOBBER_2 "lr", "cc"
155#endif
156#define __GUP_CLOBBER_4 "lr", "cc"
157#define __GUP_CLOBBER_32t_8 "lr", "cc"
158#define __GUP_CLOBBER_8 "lr", "cc"
159
160#define __get_user_x(__r2, __p, __e, __l, __s) \
161 __asm__ __volatile__ ( \
162 __asmeq("%0", "r0") __asmeq("%1", "r2") \
163 __asmeq("%3", "r1") \
164 "bl __get_user_" #__s \
165 : "=&r" (__e), "=r" (__r2) \
166 : "0" (__p), "r" (__l) \
167 : __GUP_CLOBBER_##__s)
168
169
170#ifdef __ARMEB__
171#define __get_user_x_32t(__r2, __p, __e, __l, __s) \
172 __get_user_x(__r2, __p, __e, __l, 32t_8)
173#else
174#define __get_user_x_32t __get_user_x
175#endif
176
177
178
179
180
181#ifdef __ARMEB__
182#define __get_user_x_64t(__r2, __p, __e, __l, __s) \
183 __asm__ __volatile__ ( \
184 __asmeq("%0", "r0") __asmeq("%1", "r2") \
185 __asmeq("%3", "r1") \
186 "bl __get_user_64t_" #__s \
187 : "=&r" (__e), "=r" (__r2) \
188 : "0" (__p), "r" (__l) \
189 : __GUP_CLOBBER_##__s)
190#else
191#define __get_user_x_64t __get_user_x
192#endif
193
194
195#define __get_user_check(x, p) \
196 ({ \
197 unsigned long __limit = current_thread_info()->addr_limit - 1; \
198 register typeof(*(p)) __user *__p asm("r0") = (p); \
199 register __inttype(x) __r2 asm("r2"); \
200 register unsigned long __l asm("r1") = __limit; \
201 register int __e asm("r0"); \
202 unsigned int __ua_flags = uaccess_save_and_enable(); \
203 switch (sizeof(*(__p))) { \
204 case 1: \
205 if (sizeof((x)) >= 8) \
206 __get_user_x_64t(__r2, __p, __e, __l, 1); \
207 else \
208 __get_user_x(__r2, __p, __e, __l, 1); \
209 break; \
210 case 2: \
211 if (sizeof((x)) >= 8) \
212 __get_user_x_64t(__r2, __p, __e, __l, 2); \
213 else \
214 __get_user_x(__r2, __p, __e, __l, 2); \
215 break; \
216 case 4: \
217 if (sizeof((x)) >= 8) \
218 __get_user_x_64t(__r2, __p, __e, __l, 4); \
219 else \
220 __get_user_x(__r2, __p, __e, __l, 4); \
221 break; \
222 case 8: \
223 if (sizeof((x)) < 8) \
224 __get_user_x_32t(__r2, __p, __e, __l, 4); \
225 else \
226 __get_user_x(__r2, __p, __e, __l, 8); \
227 break; \
228 default: __e = __get_user_bad(); break; \
229 } \
230 uaccess_restore(__ua_flags); \
231 x = (typeof(*(p))) __r2; \
232 __e; \
233 })
234
235#define get_user(x, p) \
236 ({ \
237 might_fault(); \
238 __get_user_check(x, p); \
239 })
240
241extern int __put_user_1(void *, unsigned int);
242extern int __put_user_2(void *, unsigned int);
243extern int __put_user_4(void *, unsigned int);
244extern int __put_user_8(void *, unsigned long long);
245
246#define __put_user_check(__pu_val, __ptr, __err, __s) \
247 ({ \
248 unsigned long __limit = current_thread_info()->addr_limit - 1; \
249 register typeof(__pu_val) __r2 asm("r2") = __pu_val; \
250 register const void __user *__p asm("r0") = __ptr; \
251 register unsigned long __l asm("r1") = __limit; \
252 register int __e asm("r0"); \
253 __asm__ __volatile__ ( \
254 __asmeq("%0", "r0") __asmeq("%2", "r2") \
255 __asmeq("%3", "r1") \
256 "bl __put_user_" #__s \
257 : "=&r" (__e) \
258 : "0" (__p), "r" (__r2), "r" (__l) \
259 : "ip", "lr", "cc"); \
260 __err = __e; \
261 })
262
263#else
264
265
266
267
268#define USER_DS KERNEL_DS
269
270#define uaccess_kernel() (true)
271#define __addr_ok(addr) ((void)(addr), 1)
272#define __range_ok(addr, size) ((void)(addr), 0)
273#define get_fs() (KERNEL_DS)
274
275static inline void set_fs(mm_segment_t fs)
276{
277}
278
279#define get_user(x, p) __get_user(x, p)
280#define __put_user_check __put_user_nocheck
281
282#endif
283
284#define access_ok(addr, size) (__range_ok(addr, size) == 0)
285
286#define user_addr_max() \
287 (uaccess_kernel() ? ~0UL : get_fs())
288
289#ifdef CONFIG_CPU_SPECTRE
290
291
292
293
294
295
296#define __get_user(x, ptr) get_user(x, ptr)
297#else
298
299
300
301
302
303
304
305
306
307
308#define __get_user(x, ptr) \
309({ \
310 long __gu_err = 0; \
311 __get_user_err((x), (ptr), __gu_err); \
312 __gu_err; \
313})
314
315#define __get_user_err(x, ptr, err) \
316do { \
317 unsigned long __gu_addr = (unsigned long)(ptr); \
318 unsigned long __gu_val; \
319 unsigned int __ua_flags; \
320 __chk_user_ptr(ptr); \
321 might_fault(); \
322 __ua_flags = uaccess_save_and_enable(); \
323 switch (sizeof(*(ptr))) { \
324 case 1: __get_user_asm_byte(__gu_val, __gu_addr, err); break; \
325 case 2: __get_user_asm_half(__gu_val, __gu_addr, err); break; \
326 case 4: __get_user_asm_word(__gu_val, __gu_addr, err); break; \
327 default: (__gu_val) = __get_user_bad(); \
328 } \
329 uaccess_restore(__ua_flags); \
330 (x) = (__typeof__(*(ptr)))__gu_val; \
331} while (0)
332
333#define __get_user_asm(x, addr, err, instr) \
334 __asm__ __volatile__( \
335 "1: " TUSER(instr) " %1, [%2], #0\n" \
336 "2:\n" \
337 " .pushsection .text.fixup,\"ax\"\n" \
338 " .align 2\n" \
339 "3: mov %0, %3\n" \
340 " mov %1, #0\n" \
341 " b 2b\n" \
342 " .popsection\n" \
343 " .pushsection __ex_table,\"a\"\n" \
344 " .align 3\n" \
345 " .long 1b, 3b\n" \
346 " .popsection" \
347 : "+r" (err), "=&r" (x) \
348 : "r" (addr), "i" (-EFAULT) \
349 : "cc")
350
351#define __get_user_asm_byte(x, addr, err) \
352 __get_user_asm(x, addr, err, ldrb)
353
354#if __LINUX_ARM_ARCH__ >= 6
355
356#define __get_user_asm_half(x, addr, err) \
357 __get_user_asm(x, addr, err, ldrh)
358
359#else
360
361#ifndef __ARMEB__
362#define __get_user_asm_half(x, __gu_addr, err) \
363({ \
364 unsigned long __b1, __b2; \
365 __get_user_asm_byte(__b1, __gu_addr, err); \
366 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
367 (x) = __b1 | (__b2 << 8); \
368})
369#else
370#define __get_user_asm_half(x, __gu_addr, err) \
371({ \
372 unsigned long __b1, __b2; \
373 __get_user_asm_byte(__b1, __gu_addr, err); \
374 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
375 (x) = (__b1 << 8) | __b2; \
376})
377#endif
378
379#endif
380
381#define __get_user_asm_word(x, addr, err) \
382 __get_user_asm(x, addr, err, ldr)
383#endif
384
385
386#define __put_user_switch(x, ptr, __err, __fn) \
387 do { \
388 const __typeof__(*(ptr)) __user *__pu_ptr = (ptr); \
389 __typeof__(*(ptr)) __pu_val = (x); \
390 unsigned int __ua_flags; \
391 might_fault(); \
392 __ua_flags = uaccess_save_and_enable(); \
393 switch (sizeof(*(ptr))) { \
394 case 1: __fn(__pu_val, __pu_ptr, __err, 1); break; \
395 case 2: __fn(__pu_val, __pu_ptr, __err, 2); break; \
396 case 4: __fn(__pu_val, __pu_ptr, __err, 4); break; \
397 case 8: __fn(__pu_val, __pu_ptr, __err, 8); break; \
398 default: __err = __put_user_bad(); break; \
399 } \
400 uaccess_restore(__ua_flags); \
401 } while (0)
402
403#define put_user(x, ptr) \
404({ \
405 int __pu_err = 0; \
406 __put_user_switch((x), (ptr), __pu_err, __put_user_check); \
407 __pu_err; \
408})
409
410#ifdef CONFIG_CPU_SPECTRE
411
412
413
414
415#define __put_user(x, ptr) put_user(x, ptr)
416
417#else
418#define __put_user(x, ptr) \
419({ \
420 long __pu_err = 0; \
421 __put_user_switch((x), (ptr), __pu_err, __put_user_nocheck); \
422 __pu_err; \
423})
424
425#define __put_user_nocheck(x, __pu_ptr, __err, __size) \
426 do { \
427 unsigned long __pu_addr = (unsigned long)__pu_ptr; \
428 __put_user_nocheck_##__size(x, __pu_addr, __err); \
429 } while (0)
430
431#define __put_user_nocheck_1 __put_user_asm_byte
432#define __put_user_nocheck_2 __put_user_asm_half
433#define __put_user_nocheck_4 __put_user_asm_word
434#define __put_user_nocheck_8 __put_user_asm_dword
435
436#define __put_user_asm(x, __pu_addr, err, instr) \
437 __asm__ __volatile__( \
438 "1: " TUSER(instr) " %1, [%2], #0\n" \
439 "2:\n" \
440 " .pushsection .text.fixup,\"ax\"\n" \
441 " .align 2\n" \
442 "3: mov %0, %3\n" \
443 " b 2b\n" \
444 " .popsection\n" \
445 " .pushsection __ex_table,\"a\"\n" \
446 " .align 3\n" \
447 " .long 1b, 3b\n" \
448 " .popsection" \
449 : "+r" (err) \
450 : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
451 : "cc")
452
453#define __put_user_asm_byte(x, __pu_addr, err) \
454 __put_user_asm(x, __pu_addr, err, strb)
455
456#if __LINUX_ARM_ARCH__ >= 6
457
458#define __put_user_asm_half(x, __pu_addr, err) \
459 __put_user_asm(x, __pu_addr, err, strh)
460
461#else
462
463#ifndef __ARMEB__
464#define __put_user_asm_half(x, __pu_addr, err) \
465({ \
466 unsigned long __temp = (__force unsigned long)(x); \
467 __put_user_asm_byte(__temp, __pu_addr, err); \
468 __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \
469})
470#else
471#define __put_user_asm_half(x, __pu_addr, err) \
472({ \
473 unsigned long __temp = (__force unsigned long)(x); \
474 __put_user_asm_byte(__temp >> 8, __pu_addr, err); \
475 __put_user_asm_byte(__temp, __pu_addr + 1, err); \
476})
477#endif
478
479#endif
480
481#define __put_user_asm_word(x, __pu_addr, err) \
482 __put_user_asm(x, __pu_addr, err, str)
483
484#ifndef __ARMEB__
485#define __reg_oper0 "%R2"
486#define __reg_oper1 "%Q2"
487#else
488#define __reg_oper0 "%Q2"
489#define __reg_oper1 "%R2"
490#endif
491
492#define __put_user_asm_dword(x, __pu_addr, err) \
493 __asm__ __volatile__( \
494 ARM( "1: " TUSER(str) " " __reg_oper1 ", [%1], #4\n" ) \
495 ARM( "2: " TUSER(str) " " __reg_oper0 ", [%1]\n" ) \
496 THUMB( "1: " TUSER(str) " " __reg_oper1 ", [%1]\n" ) \
497 THUMB( "2: " TUSER(str) " " __reg_oper0 ", [%1, #4]\n" ) \
498 "3:\n" \
499 " .pushsection .text.fixup,\"ax\"\n" \
500 " .align 2\n" \
501 "4: mov %0, %3\n" \
502 " b 3b\n" \
503 " .popsection\n" \
504 " .pushsection __ex_table,\"a\"\n" \
505 " .align 3\n" \
506 " .long 1b, 4b\n" \
507 " .long 2b, 4b\n" \
508 " .popsection" \
509 : "+r" (err), "+r" (__pu_addr) \
510 : "r" (x), "i" (-EFAULT) \
511 : "cc")
512
513#endif
514
515#ifdef CONFIG_MMU
516extern unsigned long __must_check
517arm_copy_from_user(void *to, const void __user *from, unsigned long n);
518
519static inline unsigned long __must_check
520raw_copy_from_user(void *to, const void __user *from, unsigned long n)
521{
522 unsigned int __ua_flags;
523
524 __ua_flags = uaccess_save_and_enable();
525 n = arm_copy_from_user(to, from, n);
526 uaccess_restore(__ua_flags);
527 return n;
528}
529
530extern unsigned long __must_check
531arm_copy_to_user(void __user *to, const void *from, unsigned long n);
532extern unsigned long __must_check
533__copy_to_user_std(void __user *to, const void *from, unsigned long n);
534
535static inline unsigned long __must_check
536raw_copy_to_user(void __user *to, const void *from, unsigned long n)
537{
538#ifndef CONFIG_UACCESS_WITH_MEMCPY
539 unsigned int __ua_flags;
540 __ua_flags = uaccess_save_and_enable();
541 n = arm_copy_to_user(to, from, n);
542 uaccess_restore(__ua_flags);
543 return n;
544#else
545 return arm_copy_to_user(to, from, n);
546#endif
547}
548
549extern unsigned long __must_check
550arm_clear_user(void __user *addr, unsigned long n);
551extern unsigned long __must_check
552__clear_user_std(void __user *addr, unsigned long n);
553
554static inline unsigned long __must_check
555__clear_user(void __user *addr, unsigned long n)
556{
557 unsigned int __ua_flags = uaccess_save_and_enable();
558 n = arm_clear_user(addr, n);
559 uaccess_restore(__ua_flags);
560 return n;
561}
562
563#else
564static inline unsigned long
565raw_copy_from_user(void *to, const void __user *from, unsigned long n)
566{
567 memcpy(to, (const void __force *)from, n);
568 return 0;
569}
570static inline unsigned long
571raw_copy_to_user(void __user *to, const void *from, unsigned long n)
572{
573 memcpy((void __force *)to, from, n);
574 return 0;
575}
576#define __clear_user(addr, n) (memset((void __force *)addr, 0, n), 0)
577#endif
578#define INLINE_COPY_TO_USER
579#define INLINE_COPY_FROM_USER
580
581static inline unsigned long __must_check clear_user(void __user *to, unsigned long n)
582{
583 if (access_ok(to, n))
584 n = __clear_user(to, n);
585 return n;
586}
587
588
589extern long strncpy_from_user(char *dest, const char __user *src, long count);
590
591extern __must_check long strnlen_user(const char __user *str, long n);
592
593#endif
594
