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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#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 __GUP_CLOBBER_1 "lr", "cc"
105#ifdef CONFIG_CPU_USE_DOMAINS
106#define __GUP_CLOBBER_2 "ip", "lr", "cc"
107#else
108#define __GUP_CLOBBER_2 "lr", "cc"
109#endif
110#define __GUP_CLOBBER_4 "lr", "cc"
111
112#define __get_user_x(__r2,__p,__e,__l,__s) \
113 __asm__ __volatile__ ( \
114 __asmeq("%0", "r0") __asmeq("%1", "r2") \
115 __asmeq("%3", "r1") \
116 "bl __get_user_" #__s \
117 : "=&r" (__e), "=r" (__r2) \
118 : "0" (__p), "r" (__l) \
119 : __GUP_CLOBBER_##__s)
120
121#define get_user(x,p) \
122 ({ \
123 unsigned long __limit = current_thread_info()->addr_limit - 1; \
124 register const typeof(*(p)) __user *__p asm("r0") = (p);\
125 register unsigned long __r2 asm("r2"); \
126 register unsigned long __l asm("r1") = __limit; \
127 register int __e asm("r0"); \
128 switch (sizeof(*(__p))) { \
129 case 1: \
130 __get_user_x(__r2, __p, __e, __l, 1); \
131 break; \
132 case 2: \
133 __get_user_x(__r2, __p, __e, __l, 2); \
134 break; \
135 case 4: \
136 __get_user_x(__r2, __p, __e, __l, 4); \
137 break; \
138 default: __e = __get_user_bad(); break; \
139 } \
140 x = (typeof(*(p))) __r2; \
141 __e; \
142 })
143
144extern int __put_user_1(void *, unsigned int);
145extern int __put_user_2(void *, unsigned int);
146extern int __put_user_4(void *, unsigned int);
147extern int __put_user_8(void *, unsigned long long);
148
149#define __put_user_x(__r2,__p,__e,__l,__s) \
150 __asm__ __volatile__ ( \
151 __asmeq("%0", "r0") __asmeq("%2", "r2") \
152 __asmeq("%3", "r1") \
153 "bl __put_user_" #__s \
154 : "=&r" (__e) \
155 : "0" (__p), "r" (__r2), "r" (__l) \
156 : "ip", "lr", "cc")
157
158#define put_user(x,p) \
159 ({ \
160 unsigned long __limit = current_thread_info()->addr_limit - 1; \
161 register const typeof(*(p)) __r2 asm("r2") = (x); \
162 register const typeof(*(p)) __user *__p asm("r0") = (p);\
163 register unsigned long __l asm("r1") = __limit; \
164 register int __e asm("r0"); \
165 switch (sizeof(*(__p))) { \
166 case 1: \
167 __put_user_x(__r2, __p, __e, __l, 1); \
168 break; \
169 case 2: \
170 __put_user_x(__r2, __p, __e, __l, 2); \
171 break; \
172 case 4: \
173 __put_user_x(__r2, __p, __e, __l, 4); \
174 break; \
175 case 8: \
176 __put_user_x(__r2, __p, __e, __l, 8); \
177 break; \
178 default: __e = __put_user_bad(); break; \
179 } \
180 __e; \
181 })
182
183#else /* CONFIG_MMU */
184
185/*
186 * uClinux has only one addr space, so has simplified address limits.
187 */
188#define USER_DS KERNEL_DS
189
190#define segment_eq(a,b) (1)
191#define __addr_ok(addr) (1)
192#define __range_ok(addr,size) (0)
193#define get_fs() (KERNEL_DS)
194
195static inline void set_fs(mm_segment_t fs)
196{
197}
198
199#define get_user(x,p) __get_user(x,p)
200#define put_user(x,p) __put_user(x,p)
201
202#endif /* CONFIG_MMU */
203
204#define access_ok(type,addr,size) (__range_ok(addr,size) == 0)
205
206/*
207 * The "__xxx" versions of the user access functions do not verify the
208 * address space - it must have been done previously with a separate
209 * "access_ok()" call.
210 *
211 * The "xxx_error" versions set the third argument to EFAULT if an
212 * error occurs, and leave it unchanged on success. Note that these
213 * versions are void (ie, don't return a value as such).
214 */
215#define __get_user(x,ptr) \
216({ \
217 long __gu_err = 0; \
218 __get_user_err((x),(ptr),__gu_err); \
219 __gu_err; \
220})
221
222#define __get_user_error(x,ptr,err) \
223({ \
224 __get_user_err((x),(ptr),err); \
225 (void) 0; \
226})
227
228#define __get_user_err(x,ptr,err) \
229do { \
230 unsigned long __gu_addr = (unsigned long)(ptr); \
231 unsigned long __gu_val; \
232 __chk_user_ptr(ptr); \
233 switch (sizeof(*(ptr))) { \
234 case 1: __get_user_asm_byte(__gu_val,__gu_addr,err); break; \
235 case 2: __get_user_asm_half(__gu_val,__gu_addr,err); break; \
236 case 4: __get_user_asm_word(__gu_val,__gu_addr,err); break; \
237 default: (__gu_val) = __get_user_bad(); \
238 } \
239 (x) = (__typeof__(*(ptr)))__gu_val; \
240} while (0)
241
242#define __get_user_asm_byte(x,addr,err) \
243 __asm__ __volatile__( \
244 "1: " TUSER(ldrb) " %1,[%2],#0\n" \
245 "2:\n" \
246 " .pushsection .fixup,\"ax\"\n" \
247 " .align 2\n" \
248 "3: mov %0, %3\n" \
249 " mov %1, #0\n" \
250 " b 2b\n" \
251 " .popsection\n" \
252 " .pushsection __ex_table,\"a\"\n" \
253 " .align 3\n" \
254 " .long 1b, 3b\n" \
255 " .popsection" \
256 : "+r" (err), "=&r" (x) \
257 : "r" (addr), "i" (-EFAULT) \
258 : "cc")
259
260#ifndef __ARMEB__
261#define __get_user_asm_half(x,__gu_addr,err) \
262({ \
263 unsigned long __b1, __b2; \
264 __get_user_asm_byte(__b1, __gu_addr, err); \
265 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
266 (x) = __b1 | (__b2 << 8); \
267})
268#else
269#define __get_user_asm_half(x,__gu_addr,err) \
270({ \
271 unsigned long __b1, __b2; \
272 __get_user_asm_byte(__b1, __gu_addr, err); \
273 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
274 (x) = (__b1 << 8) | __b2; \
275})
276#endif
277
278#define __get_user_asm_word(x,addr,err) \
279 __asm__ __volatile__( \
280 "1: " TUSER(ldr) " %1,[%2],#0\n" \
281 "2:\n" \
282 " .pushsection .fixup,\"ax\"\n" \
283 " .align 2\n" \
284 "3: mov %0, %3\n" \
285 " mov %1, #0\n" \
286 " b 2b\n" \
287 " .popsection\n" \
288 " .pushsection __ex_table,\"a\"\n" \
289 " .align 3\n" \
290 " .long 1b, 3b\n" \
291 " .popsection" \
292 : "+r" (err), "=&r" (x) \
293 : "r" (addr), "i" (-EFAULT) \
294 : "cc")
295
296#define __put_user(x,ptr) \
297({ \
298 long __pu_err = 0; \
299 __put_user_err((x),(ptr),__pu_err); \
300 __pu_err; \
301})
302
303#define __put_user_error(x,ptr,err) \
304({ \
305 __put_user_err((x),(ptr),err); \
306 (void) 0; \
307})
308
309#define __put_user_err(x,ptr,err) \
310do { \
311 unsigned long __pu_addr = (unsigned long)(ptr); \
312 __typeof__(*(ptr)) __pu_val = (x); \
313 __chk_user_ptr(ptr); \
314 switch (sizeof(*(ptr))) { \
315 case 1: __put_user_asm_byte(__pu_val,__pu_addr,err); break; \
316 case 2: __put_user_asm_half(__pu_val,__pu_addr,err); break; \
317 case 4: __put_user_asm_word(__pu_val,__pu_addr,err); break; \
318 case 8: __put_user_asm_dword(__pu_val,__pu_addr,err); break; \
319 default: __put_user_bad(); \
320 } \
321} while (0)
322
323#define __put_user_asm_byte(x,__pu_addr,err) \
324 __asm__ __volatile__( \
325 "1: " TUSER(strb) " %1,[%2],#0\n" \
326 "2:\n" \
327 " .pushsection .fixup,\"ax\"\n" \
328 " .align 2\n" \
329 "3: mov %0, %3\n" \
330 " b 2b\n" \
331 " .popsection\n" \
332 " .pushsection __ex_table,\"a\"\n" \
333 " .align 3\n" \
334 " .long 1b, 3b\n" \
335 " .popsection" \
336 : "+r" (err) \
337 : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
338 : "cc")
339
340#ifndef __ARMEB__
341#define __put_user_asm_half(x,__pu_addr,err) \
342({ \
343 unsigned long __temp = (unsigned long)(x); \
344 __put_user_asm_byte(__temp, __pu_addr, err); \
345 __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \
346})
347#else
348#define __put_user_asm_half(x,__pu_addr,err) \
349({ \
350 unsigned long __temp = (unsigned long)(x); \
351 __put_user_asm_byte(__temp >> 8, __pu_addr, err); \
352 __put_user_asm_byte(__temp, __pu_addr + 1, err); \
353})
354#endif
355
356#define __put_user_asm_word(x,__pu_addr,err) \
357 __asm__ __volatile__( \
358 "1: " TUSER(str) " %1,[%2],#0\n" \
359 "2:\n" \
360 " .pushsection .fixup,\"ax\"\n" \
361 " .align 2\n" \
362 "3: mov %0, %3\n" \
363 " b 2b\n" \
364 " .popsection\n" \
365 " .pushsection __ex_table,\"a\"\n" \
366 " .align 3\n" \
367 " .long 1b, 3b\n" \
368 " .popsection" \
369 : "+r" (err) \
370 : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
371 : "cc")
372
373#ifndef __ARMEB__
374#define __reg_oper0 "%R2"
375#define __reg_oper1 "%Q2"
376#else
377#define __reg_oper0 "%Q2"
378#define __reg_oper1 "%R2"
379#endif
380
381#define __put_user_asm_dword(x,__pu_addr,err) \
382 __asm__ __volatile__( \
383 ARM( "1: " TUSER(str) " " __reg_oper1 ", [%1], #4\n" ) \
384 ARM( "2: " TUSER(str) " " __reg_oper0 ", [%1]\n" ) \
385 THUMB( "1: " TUSER(str) " " __reg_oper1 ", [%1]\n" ) \
386 THUMB( "2: " TUSER(str) " " __reg_oper0 ", [%1, #4]\n" ) \
387 "3:\n" \
388 " .pushsection .fixup,\"ax\"\n" \
389 " .align 2\n" \
390 "4: mov %0, %3\n" \
391 " b 3b\n" \
392 " .popsection\n" \
393 " .pushsection __ex_table,\"a\"\n" \
394 " .align 3\n" \
395 " .long 1b, 4b\n" \
396 " .long 2b, 4b\n" \
397 " .popsection" \
398 : "+r" (err), "+r" (__pu_addr) \
399 : "r" (x), "i" (-EFAULT) \
400 : "cc")
401
402
403#ifdef CONFIG_MMU
404extern unsigned long __must_check __copy_from_user(void *to, const void __user *from, unsigned long n);
405extern unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n);
406extern unsigned long __must_check __copy_to_user_std(void __user *to, const void *from, unsigned long n);
407extern unsigned long __must_check __clear_user(void __user *addr, unsigned long n);
408extern unsigned long __must_check __clear_user_std(void __user *addr, unsigned long n);
409#else
410#define __copy_from_user(to,from,n) (memcpy(to, (void __force *)from, n), 0)
411#define __copy_to_user(to,from,n) (memcpy((void __force *)to, from, n), 0)
412#define __clear_user(addr,n) (memset((void __force *)addr, 0, n), 0)
413#endif
414
415extern unsigned long __must_check __strncpy_from_user(char *to, const char __user *from, unsigned long count);
416extern unsigned long __must_check __strnlen_user(const char __user *s, long n);
417
418static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n)
419{
420 if (access_ok(VERIFY_READ, from, n))
421 n = __copy_from_user(to, from, n);
422 else /* security hole - plug it */
423 memset(to, 0, n);
424 return n;
425}
426
427static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n)
428{
429 if (access_ok(VERIFY_WRITE, to, n))
430 n = __copy_to_user(to, from, n);
431 return n;
432}
433
434#define __copy_to_user_inatomic __copy_to_user
435#define __copy_from_user_inatomic __copy_from_user
436
437static inline unsigned long __must_check clear_user(void __user *to, unsigned long n)
438{
439 if (access_ok(VERIFY_WRITE, to, n))
440 n = __clear_user(to, n);
441 return n;
442}
443
444static inline long __must_check strncpy_from_user(char *dst, const char __user *src, long count)
445{
446 long res = -EFAULT;
447 if (access_ok(VERIFY_READ, src, 1))
448 res = __strncpy_from_user(dst, src, count);
449 return res;
450}
451
452#define strlen_user(s) strnlen_user(s, ~0UL >> 1)
453
454static inline long __must_check strnlen_user(const char __user *s, long n)
455{
456 unsigned long res = 0;
457
458 if (__addr_ok(s))
459 res = __strnlen_user(s, n);
460
461 return res;
462}
463
464#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 <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#define __addr_ok(addr) ({ \
108 unsigned long flag; \
109 __asm__("cmp %2, %0; movlo %0, #0" \
110 : "=&r" (flag) \
111 : "0" (current_thread_info()->addr_limit), "r" (addr) \
112 : "cc"); \
113 (flag == 0); })
114
115/* We use 33-bit arithmetic here... */
116#define __range_ok(addr, size) ({ \
117 unsigned long flag, roksum; \
118 __chk_user_ptr(addr); \
119 __asm__("adds %1, %2, %3; sbcccs %1, %1, %0; movcc %0, #0" \
120 : "=&r" (flag), "=&r" (roksum) \
121 : "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit) \
122 : "cc"); \
123 flag; })
124
125/*
126 * Single-value transfer routines. They automatically use the right
127 * size if we just have the right pointer type. Note that the functions
128 * which read from user space (*get_*) need to take care not to leak
129 * kernel data even if the calling code is buggy and fails to check
130 * the return value. This means zeroing out the destination variable
131 * or buffer on error. Normally this is done out of line by the
132 * fixup code, but there are a few places where it intrudes on the
133 * main code path. When we only write to user space, there is no
134 * problem.
135 */
136extern int __get_user_1(void *);
137extern int __get_user_2(void *);
138extern int __get_user_4(void *);
139extern int __get_user_32t_8(void *);
140extern int __get_user_8(void *);
141extern int __get_user_64t_1(void *);
142extern int __get_user_64t_2(void *);
143extern int __get_user_64t_4(void *);
144
145#define __GUP_CLOBBER_1 "lr", "cc"
146#ifdef CONFIG_CPU_USE_DOMAINS
147#define __GUP_CLOBBER_2 "ip", "lr", "cc"
148#else
149#define __GUP_CLOBBER_2 "lr", "cc"
150#endif
151#define __GUP_CLOBBER_4 "lr", "cc"
152#define __GUP_CLOBBER_32t_8 "lr", "cc"
153#define __GUP_CLOBBER_8 "lr", "cc"
154
155#define __get_user_x(__r2, __p, __e, __l, __s) \
156 __asm__ __volatile__ ( \
157 __asmeq("%0", "r0") __asmeq("%1", "r2") \
158 __asmeq("%3", "r1") \
159 "bl __get_user_" #__s \
160 : "=&r" (__e), "=r" (__r2) \
161 : "0" (__p), "r" (__l) \
162 : __GUP_CLOBBER_##__s)
163
164/* narrowing a double-word get into a single 32bit word register: */
165#ifdef __ARMEB__
166#define __get_user_x_32t(__r2, __p, __e, __l, __s) \
167 __get_user_x(__r2, __p, __e, __l, 32t_8)
168#else
169#define __get_user_x_32t __get_user_x
170#endif
171
172/*
173 * storing result into proper least significant word of 64bit target var,
174 * different only for big endian case where 64 bit __r2 lsw is r3:
175 */
176#ifdef __ARMEB__
177#define __get_user_x_64t(__r2, __p, __e, __l, __s) \
178 __asm__ __volatile__ ( \
179 __asmeq("%0", "r0") __asmeq("%1", "r2") \
180 __asmeq("%3", "r1") \
181 "bl __get_user_64t_" #__s \
182 : "=&r" (__e), "=r" (__r2) \
183 : "0" (__p), "r" (__l) \
184 : __GUP_CLOBBER_##__s)
185#else
186#define __get_user_x_64t __get_user_x
187#endif
188
189
190#define __get_user_check(x, p) \
191 ({ \
192 unsigned long __limit = current_thread_info()->addr_limit - 1; \
193 register const typeof(*(p)) __user *__p asm("r0") = (p);\
194 register typeof(x) __r2 asm("r2"); \
195 register unsigned long __l asm("r1") = __limit; \
196 register int __e asm("r0"); \
197 unsigned int __ua_flags = uaccess_save_and_enable(); \
198 switch (sizeof(*(__p))) { \
199 case 1: \
200 if (sizeof((x)) >= 8) \
201 __get_user_x_64t(__r2, __p, __e, __l, 1); \
202 else \
203 __get_user_x(__r2, __p, __e, __l, 1); \
204 break; \
205 case 2: \
206 if (sizeof((x)) >= 8) \
207 __get_user_x_64t(__r2, __p, __e, __l, 2); \
208 else \
209 __get_user_x(__r2, __p, __e, __l, 2); \
210 break; \
211 case 4: \
212 if (sizeof((x)) >= 8) \
213 __get_user_x_64t(__r2, __p, __e, __l, 4); \
214 else \
215 __get_user_x(__r2, __p, __e, __l, 4); \
216 break; \
217 case 8: \
218 if (sizeof((x)) < 8) \
219 __get_user_x_32t(__r2, __p, __e, __l, 4); \
220 else \
221 __get_user_x(__r2, __p, __e, __l, 8); \
222 break; \
223 default: __e = __get_user_bad(); break; \
224 } \
225 uaccess_restore(__ua_flags); \
226 x = (typeof(*(p))) __r2; \
227 __e; \
228 })
229
230#define get_user(x, p) \
231 ({ \
232 might_fault(); \
233 __get_user_check(x, p); \
234 })
235
236extern int __put_user_1(void *, unsigned int);
237extern int __put_user_2(void *, unsigned int);
238extern int __put_user_4(void *, unsigned int);
239extern int __put_user_8(void *, unsigned long long);
240
241#define __put_user_x(__r2, __p, __e, __l, __s) \
242 __asm__ __volatile__ ( \
243 __asmeq("%0", "r0") __asmeq("%2", "r2") \
244 __asmeq("%3", "r1") \
245 "bl __put_user_" #__s \
246 : "=&r" (__e) \
247 : "0" (__p), "r" (__r2), "r" (__l) \
248 : "ip", "lr", "cc")
249
250#define __put_user_check(x, p) \
251 ({ \
252 unsigned long __limit = current_thread_info()->addr_limit - 1; \
253 const typeof(*(p)) __user *__tmp_p = (p); \
254 register const typeof(*(p)) __r2 asm("r2") = (x); \
255 register const typeof(*(p)) __user *__p asm("r0") = __tmp_p; \
256 register unsigned long __l asm("r1") = __limit; \
257 register int __e asm("r0"); \
258 unsigned int __ua_flags = uaccess_save_and_enable(); \
259 switch (sizeof(*(__p))) { \
260 case 1: \
261 __put_user_x(__r2, __p, __e, __l, 1); \
262 break; \
263 case 2: \
264 __put_user_x(__r2, __p, __e, __l, 2); \
265 break; \
266 case 4: \
267 __put_user_x(__r2, __p, __e, __l, 4); \
268 break; \
269 case 8: \
270 __put_user_x(__r2, __p, __e, __l, 8); \
271 break; \
272 default: __e = __put_user_bad(); break; \
273 } \
274 uaccess_restore(__ua_flags); \
275 __e; \
276 })
277
278#define put_user(x, p) \
279 ({ \
280 might_fault(); \
281 __put_user_check(x, p); \
282 })
283
284#else /* CONFIG_MMU */
285
286/*
287 * uClinux has only one addr space, so has simplified address limits.
288 */
289#define USER_DS KERNEL_DS
290
291#define segment_eq(a, b) (1)
292#define __addr_ok(addr) ((void)(addr), 1)
293#define __range_ok(addr, size) ((void)(addr), 0)
294#define get_fs() (KERNEL_DS)
295
296static inline void set_fs(mm_segment_t fs)
297{
298}
299
300#define get_user(x, p) __get_user(x, p)
301#define put_user(x, p) __put_user(x, p)
302
303#endif /* CONFIG_MMU */
304
305#define access_ok(type, addr, size) (__range_ok(addr, size) == 0)
306
307#define user_addr_max() \
308 (segment_eq(get_fs(), KERNEL_DS) ? ~0UL : get_fs())
309
310/*
311 * The "__xxx" versions of the user access functions do not verify the
312 * address space - it must have been done previously with a separate
313 * "access_ok()" call.
314 *
315 * The "xxx_error" versions set the third argument to EFAULT if an
316 * error occurs, and leave it unchanged on success. Note that these
317 * versions are void (ie, don't return a value as such).
318 */
319#define __get_user(x, ptr) \
320({ \
321 long __gu_err = 0; \
322 __get_user_err((x), (ptr), __gu_err); \
323 __gu_err; \
324})
325
326#define __get_user_error(x, ptr, err) \
327({ \
328 __get_user_err((x), (ptr), err); \
329 (void) 0; \
330})
331
332#define __get_user_err(x, ptr, err) \
333do { \
334 unsigned long __gu_addr = (unsigned long)(ptr); \
335 unsigned long __gu_val; \
336 unsigned int __ua_flags; \
337 __chk_user_ptr(ptr); \
338 might_fault(); \
339 __ua_flags = uaccess_save_and_enable(); \
340 switch (sizeof(*(ptr))) { \
341 case 1: __get_user_asm_byte(__gu_val, __gu_addr, err); break; \
342 case 2: __get_user_asm_half(__gu_val, __gu_addr, err); break; \
343 case 4: __get_user_asm_word(__gu_val, __gu_addr, err); break; \
344 default: (__gu_val) = __get_user_bad(); \
345 } \
346 uaccess_restore(__ua_flags); \
347 (x) = (__typeof__(*(ptr)))__gu_val; \
348} while (0)
349
350#define __get_user_asm(x, addr, err, instr) \
351 __asm__ __volatile__( \
352 "1: " TUSER(instr) " %1, [%2], #0\n" \
353 "2:\n" \
354 " .pushsection .text.fixup,\"ax\"\n" \
355 " .align 2\n" \
356 "3: mov %0, %3\n" \
357 " mov %1, #0\n" \
358 " b 2b\n" \
359 " .popsection\n" \
360 " .pushsection __ex_table,\"a\"\n" \
361 " .align 3\n" \
362 " .long 1b, 3b\n" \
363 " .popsection" \
364 : "+r" (err), "=&r" (x) \
365 : "r" (addr), "i" (-EFAULT) \
366 : "cc")
367
368#define __get_user_asm_byte(x, addr, err) \
369 __get_user_asm(x, addr, err, ldrb)
370
371#ifndef __ARMEB__
372#define __get_user_asm_half(x, __gu_addr, err) \
373({ \
374 unsigned long __b1, __b2; \
375 __get_user_asm_byte(__b1, __gu_addr, err); \
376 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
377 (x) = __b1 | (__b2 << 8); \
378})
379#else
380#define __get_user_asm_half(x, __gu_addr, err) \
381({ \
382 unsigned long __b1, __b2; \
383 __get_user_asm_byte(__b1, __gu_addr, err); \
384 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
385 (x) = (__b1 << 8) | __b2; \
386})
387#endif
388
389#define __get_user_asm_word(x, addr, err) \
390 __get_user_asm(x, addr, err, ldr)
391
392#define __put_user(x, ptr) \
393({ \
394 long __pu_err = 0; \
395 __put_user_err((x), (ptr), __pu_err); \
396 __pu_err; \
397})
398
399#define __put_user_error(x, ptr, err) \
400({ \
401 __put_user_err((x), (ptr), err); \
402 (void) 0; \
403})
404
405#define __put_user_err(x, ptr, err) \
406do { \
407 unsigned long __pu_addr = (unsigned long)(ptr); \
408 unsigned int __ua_flags; \
409 __typeof__(*(ptr)) __pu_val = (x); \
410 __chk_user_ptr(ptr); \
411 might_fault(); \
412 __ua_flags = uaccess_save_and_enable(); \
413 switch (sizeof(*(ptr))) { \
414 case 1: __put_user_asm_byte(__pu_val, __pu_addr, err); break; \
415 case 2: __put_user_asm_half(__pu_val, __pu_addr, err); break; \
416 case 4: __put_user_asm_word(__pu_val, __pu_addr, err); break; \
417 case 8: __put_user_asm_dword(__pu_val, __pu_addr, err); break; \
418 default: __put_user_bad(); \
419 } \
420 uaccess_restore(__ua_flags); \
421} while (0)
422
423#define __put_user_asm(x, __pu_addr, err, instr) \
424 __asm__ __volatile__( \
425 "1: " TUSER(instr) " %1, [%2], #0\n" \
426 "2:\n" \
427 " .pushsection .text.fixup,\"ax\"\n" \
428 " .align 2\n" \
429 "3: mov %0, %3\n" \
430 " b 2b\n" \
431 " .popsection\n" \
432 " .pushsection __ex_table,\"a\"\n" \
433 " .align 3\n" \
434 " .long 1b, 3b\n" \
435 " .popsection" \
436 : "+r" (err) \
437 : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
438 : "cc")
439
440#define __put_user_asm_byte(x, __pu_addr, err) \
441 __put_user_asm(x, __pu_addr, err, strb)
442
443#ifndef __ARMEB__
444#define __put_user_asm_half(x, __pu_addr, err) \
445({ \
446 unsigned long __temp = (__force unsigned long)(x); \
447 __put_user_asm_byte(__temp, __pu_addr, err); \
448 __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \
449})
450#else
451#define __put_user_asm_half(x, __pu_addr, err) \
452({ \
453 unsigned long __temp = (__force unsigned long)(x); \
454 __put_user_asm_byte(__temp >> 8, __pu_addr, err); \
455 __put_user_asm_byte(__temp, __pu_addr + 1, err); \
456})
457#endif
458
459#define __put_user_asm_word(x, __pu_addr, err) \
460 __put_user_asm(x, __pu_addr, err, str)
461
462#ifndef __ARMEB__
463#define __reg_oper0 "%R2"
464#define __reg_oper1 "%Q2"
465#else
466#define __reg_oper0 "%Q2"
467#define __reg_oper1 "%R2"
468#endif
469
470#define __put_user_asm_dword(x, __pu_addr, err) \
471 __asm__ __volatile__( \
472 ARM( "1: " TUSER(str) " " __reg_oper1 ", [%1], #4\n" ) \
473 ARM( "2: " TUSER(str) " " __reg_oper0 ", [%1]\n" ) \
474 THUMB( "1: " TUSER(str) " " __reg_oper1 ", [%1]\n" ) \
475 THUMB( "2: " TUSER(str) " " __reg_oper0 ", [%1, #4]\n" ) \
476 "3:\n" \
477 " .pushsection .text.fixup,\"ax\"\n" \
478 " .align 2\n" \
479 "4: mov %0, %3\n" \
480 " b 3b\n" \
481 " .popsection\n" \
482 " .pushsection __ex_table,\"a\"\n" \
483 " .align 3\n" \
484 " .long 1b, 4b\n" \
485 " .long 2b, 4b\n" \
486 " .popsection" \
487 : "+r" (err), "+r" (__pu_addr) \
488 : "r" (x), "i" (-EFAULT) \
489 : "cc")
490
491
492#ifdef CONFIG_MMU
493extern unsigned long __must_check
494arm_copy_from_user(void *to, const void __user *from, unsigned long n);
495
496static inline unsigned long __must_check
497__copy_from_user(void *to, const void __user *from, unsigned long n)
498{
499 unsigned int __ua_flags = uaccess_save_and_enable();
500 n = arm_copy_from_user(to, from, n);
501 uaccess_restore(__ua_flags);
502 return n;
503}
504
505extern unsigned long __must_check
506arm_copy_to_user(void __user *to, const void *from, unsigned long n);
507extern unsigned long __must_check
508__copy_to_user_std(void __user *to, const void *from, unsigned long n);
509
510static inline unsigned long __must_check
511__copy_to_user(void __user *to, const void *from, unsigned long n)
512{
513#ifndef CONFIG_UACCESS_WITH_MEMCPY
514 unsigned int __ua_flags = uaccess_save_and_enable();
515 n = arm_copy_to_user(to, from, n);
516 uaccess_restore(__ua_flags);
517 return n;
518#else
519 return arm_copy_to_user(to, from, n);
520#endif
521}
522
523extern unsigned long __must_check
524arm_clear_user(void __user *addr, unsigned long n);
525extern unsigned long __must_check
526__clear_user_std(void __user *addr, unsigned long n);
527
528static inline unsigned long __must_check
529__clear_user(void __user *addr, unsigned long n)
530{
531 unsigned int __ua_flags = uaccess_save_and_enable();
532 n = arm_clear_user(addr, n);
533 uaccess_restore(__ua_flags);
534 return n;
535}
536
537#else
538#define __copy_from_user(to, from, n) (memcpy(to, (void __force *)from, n), 0)
539#define __copy_to_user(to, from, n) (memcpy((void __force *)to, from, n), 0)
540#define __clear_user(addr, n) (memset((void __force *)addr, 0, n), 0)
541#endif
542
543static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n)
544{
545 if (access_ok(VERIFY_READ, from, n))
546 n = __copy_from_user(to, from, n);
547 else /* security hole - plug it */
548 memset(to, 0, n);
549 return n;
550}
551
552static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n)
553{
554 if (access_ok(VERIFY_WRITE, to, n))
555 n = __copy_to_user(to, from, n);
556 return n;
557}
558
559#define __copy_to_user_inatomic __copy_to_user
560#define __copy_from_user_inatomic __copy_from_user
561
562static inline unsigned long __must_check clear_user(void __user *to, unsigned long n)
563{
564 if (access_ok(VERIFY_WRITE, to, n))
565 n = __clear_user(to, n);
566 return n;
567}
568
569/* These are from lib/ code, and use __get_user() and friends */
570extern long strncpy_from_user(char *dest, const char __user *src, long count);
571
572extern __must_check long strlen_user(const char __user *str);
573extern __must_check long strnlen_user(const char __user *str, long n);
574
575#endif /* _ASMARM_UACCESS_H */