1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_X86_UACCESS_H
3#define _ASM_X86_UACCESS_H
4/*
5 * User space memory access functions
6 */
7#include <linux/compiler.h>
8#include <linux/instrumented.h>
9#include <linux/kasan-checks.h>
10#include <linux/mm_types.h>
11#include <linux/string.h>
12#include <linux/mmap_lock.h>
13#include <asm/asm.h>
14#include <asm/page.h>
15#include <asm/smap.h>
16#include <asm/extable.h>
17#include <asm/tlbflush.h>
18
19#ifdef CONFIG_X86_32
20# include <asm/uaccess_32.h>
21#else
22# include <asm/uaccess_64.h>
23#endif
24
25#include <asm-generic/access_ok.h>
26
27extern int __get_user_1(void);
28extern int __get_user_2(void);
29extern int __get_user_4(void);
30extern int __get_user_8(void);
31extern int __get_user_nocheck_1(void);
32extern int __get_user_nocheck_2(void);
33extern int __get_user_nocheck_4(void);
34extern int __get_user_nocheck_8(void);
35extern int __get_user_bad(void);
36
37#define __uaccess_begin() stac()
38#define __uaccess_end() clac()
39#define __uaccess_begin_nospec() \
40({ \
41 stac(); \
42 barrier_nospec(); \
43})
44
45/*
46 * This is the smallest unsigned integer type that can fit a value
47 * (up to 'long long')
48 */
49#define __inttype(x) __typeof__( \
50 __typefits(x,char, \
51 __typefits(x,short, \
52 __typefits(x,int, \
53 __typefits(x,long,0ULL)))))
54
55#define __typefits(x,type,not) \
56 __builtin_choose_expr(sizeof(x)<=sizeof(type),(unsigned type)0,not)
57
58/*
59 * This is used for both get_user() and __get_user() to expand to
60 * the proper special function call that has odd calling conventions
61 * due to returning both a value and an error, and that depends on
62 * the size of the pointer passed in.
63 *
64 * Careful: we have to cast the result to the type of the pointer
65 * for sign reasons.
66 *
67 * The use of _ASM_DX as the register specifier is a bit of a
68 * simplification, as gcc only cares about it as the starting point
69 * and not size: for a 64-bit value it will use %ecx:%edx on 32 bits
70 * (%ecx being the next register in gcc's x86 register sequence), and
71 * %rdx on 64 bits.
72 *
73 * Clang/LLVM cares about the size of the register, but still wants
74 * the base register for something that ends up being a pair.
75 */
76#define do_get_user_call(fn,x,ptr) \
77({ \
78 int __ret_gu; \
79 register __inttype(*(ptr)) __val_gu asm("%"_ASM_DX); \
80 __chk_user_ptr(ptr); \
81 asm volatile("call __" #fn "_%c[size]" \
82 : "=a" (__ret_gu), "=r" (__val_gu), \
83 ASM_CALL_CONSTRAINT \
84 : "0" (ptr), [size] "i" (sizeof(*(ptr)))); \
85 instrument_get_user(__val_gu); \
86 (x) = (__force __typeof__(*(ptr))) __val_gu; \
87 __builtin_expect(__ret_gu, 0); \
88})
89
90/**
91 * get_user - Get a simple variable from user space.
92 * @x: Variable to store result.
93 * @ptr: Source address, in user space.
94 *
95 * Context: User context only. This function may sleep if pagefaults are
96 * enabled.
97 *
98 * This macro copies a single simple variable from user space to kernel
99 * space. It supports simple types like char and int, but not larger
100 * data types like structures or arrays.
101 *
102 * @ptr must have pointer-to-simple-variable type, and the result of
103 * dereferencing @ptr must be assignable to @x without a cast.
104 *
105 * Return: zero on success, or -EFAULT on error.
106 * On error, the variable @x is set to zero.
107 */
108#define get_user(x,ptr) ({ might_fault(); do_get_user_call(get_user,x,ptr); })
109
110/**
111 * __get_user - Get a simple variable from user space, with less checking.
112 * @x: Variable to store result.
113 * @ptr: Source address, in user space.
114 *
115 * Context: User context only. This function may sleep if pagefaults are
116 * enabled.
117 *
118 * This macro copies a single simple variable from user space to kernel
119 * space. It supports simple types like char and int, but not larger
120 * data types like structures or arrays.
121 *
122 * @ptr must have pointer-to-simple-variable type, and the result of
123 * dereferencing @ptr must be assignable to @x without a cast.
124 *
125 * Caller must check the pointer with access_ok() before calling this
126 * function.
127 *
128 * Return: zero on success, or -EFAULT on error.
129 * On error, the variable @x is set to zero.
130 */
131#define __get_user(x,ptr) do_get_user_call(get_user_nocheck,x,ptr)
132
133
134#ifdef CONFIG_X86_32
135#define __put_user_goto_u64(x, addr, label) \
136 asm goto("\n" \
137 "1: movl %%eax,0(%1)\n" \
138 "2: movl %%edx,4(%1)\n" \
139 _ASM_EXTABLE_UA(1b, %l2) \
140 _ASM_EXTABLE_UA(2b, %l2) \
141 : : "A" (x), "r" (addr) \
142 : : label)
143
144#else
145#define __put_user_goto_u64(x, ptr, label) \
146 __put_user_goto(x, ptr, "q", "er", label)
147#endif
148
149extern void __put_user_bad(void);
150
151/*
152 * Strange magic calling convention: pointer in %ecx,
153 * value in %eax(:%edx), return value in %ecx. clobbers %rbx
154 */
155extern void __put_user_1(void);
156extern void __put_user_2(void);
157extern void __put_user_4(void);
158extern void __put_user_8(void);
159extern void __put_user_nocheck_1(void);
160extern void __put_user_nocheck_2(void);
161extern void __put_user_nocheck_4(void);
162extern void __put_user_nocheck_8(void);
163
164/*
165 * ptr must be evaluated and assigned to the temporary __ptr_pu before
166 * the assignment of x to __val_pu, to avoid any function calls
167 * involved in the ptr expression (possibly implicitly generated due
168 * to KASAN) from clobbering %ax.
169 */
170#define do_put_user_call(fn,x,ptr) \
171({ \
172 int __ret_pu; \
173 void __user *__ptr_pu; \
174 register __typeof__(*(ptr)) __val_pu asm("%"_ASM_AX); \
175 __typeof__(*(ptr)) __x = (x); /* eval x once */ \
176 __typeof__(ptr) __ptr = (ptr); /* eval ptr once */ \
177 __chk_user_ptr(__ptr); \
178 __ptr_pu = __ptr; \
179 __val_pu = __x; \
180 asm volatile("call __" #fn "_%c[size]" \
181 : "=c" (__ret_pu), \
182 ASM_CALL_CONSTRAINT \
183 : "0" (__ptr_pu), \
184 "r" (__val_pu), \
185 [size] "i" (sizeof(*(ptr))) \
186 :"ebx"); \
187 instrument_put_user(__x, __ptr, sizeof(*(ptr))); \
188 __builtin_expect(__ret_pu, 0); \
189})
190
191/**
192 * put_user - Write a simple value into user space.
193 * @x: Value to copy to user space.
194 * @ptr: Destination address, in user space.
195 *
196 * Context: User context only. This function may sleep if pagefaults are
197 * enabled.
198 *
199 * This macro copies a single simple value from kernel space to user
200 * space. It supports simple types like char and int, but not larger
201 * data types like structures or arrays.
202 *
203 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
204 * to the result of dereferencing @ptr.
205 *
206 * Return: zero on success, or -EFAULT on error.
207 */
208#define put_user(x, ptr) ({ might_fault(); do_put_user_call(put_user,x,ptr); })
209
210/**
211 * __put_user - Write a simple value into user space, with less checking.
212 * @x: Value to copy to user space.
213 * @ptr: Destination address, in user space.
214 *
215 * Context: User context only. This function may sleep if pagefaults are
216 * enabled.
217 *
218 * This macro copies a single simple value from kernel space to user
219 * space. It supports simple types like char and int, but not larger
220 * data types like structures or arrays.
221 *
222 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
223 * to the result of dereferencing @ptr.
224 *
225 * Caller must check the pointer with access_ok() before calling this
226 * function.
227 *
228 * Return: zero on success, or -EFAULT on error.
229 */
230#define __put_user(x, ptr) do_put_user_call(put_user_nocheck,x,ptr)
231
232#define __put_user_size(x, ptr, size, label) \
233do { \
234 __typeof__(*(ptr)) __x = (x); /* eval x once */ \
235 __typeof__(ptr) __ptr = (ptr); /* eval ptr once */ \
236 __chk_user_ptr(__ptr); \
237 switch (size) { \
238 case 1: \
239 __put_user_goto(__x, __ptr, "b", "iq", label); \
240 break; \
241 case 2: \
242 __put_user_goto(__x, __ptr, "w", "ir", label); \
243 break; \
244 case 4: \
245 __put_user_goto(__x, __ptr, "l", "ir", label); \
246 break; \
247 case 8: \
248 __put_user_goto_u64(__x, __ptr, label); \
249 break; \
250 default: \
251 __put_user_bad(); \
252 } \
253 instrument_put_user(__x, __ptr, size); \
254} while (0)
255
256#ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT
257
258#ifdef CONFIG_X86_32
259#define __get_user_asm_u64(x, ptr, label) do { \
260 unsigned int __gu_low, __gu_high; \
261 const unsigned int __user *__gu_ptr; \
262 __gu_ptr = (const void __user *)(ptr); \
263 __get_user_asm(__gu_low, __gu_ptr, "l", "=r", label); \
264 __get_user_asm(__gu_high, __gu_ptr+1, "l", "=r", label); \
265 (x) = ((unsigned long long)__gu_high << 32) | __gu_low; \
266} while (0)
267#else
268#define __get_user_asm_u64(x, ptr, label) \
269 __get_user_asm(x, ptr, "q", "=r", label)
270#endif
271
272#define __get_user_size(x, ptr, size, label) \
273do { \
274 __chk_user_ptr(ptr); \
275 switch (size) { \
276 case 1: { \
277 unsigned char x_u8__; \
278 __get_user_asm(x_u8__, ptr, "b", "=q", label); \
279 (x) = x_u8__; \
280 break; \
281 } \
282 case 2: \
283 __get_user_asm(x, ptr, "w", "=r", label); \
284 break; \
285 case 4: \
286 __get_user_asm(x, ptr, "l", "=r", label); \
287 break; \
288 case 8: \
289 __get_user_asm_u64(x, ptr, label); \
290 break; \
291 default: \
292 (x) = __get_user_bad(); \
293 } \
294 instrument_get_user(x); \
295} while (0)
296
297#define __get_user_asm(x, addr, itype, ltype, label) \
298 asm_goto_output("\n" \
299 "1: mov"itype" %[umem],%[output]\n" \
300 _ASM_EXTABLE_UA(1b, %l2) \
301 : [output] ltype(x) \
302 : [umem] "m" (__m(addr)) \
303 : : label)
304
305#else // !CONFIG_CC_HAS_ASM_GOTO_OUTPUT
306
307#ifdef CONFIG_X86_32
308#define __get_user_asm_u64(x, ptr, retval) \
309({ \
310 __typeof__(ptr) __ptr = (ptr); \
311 asm volatile("\n" \
312 "1: movl %[lowbits],%%eax\n" \
313 "2: movl %[highbits],%%edx\n" \
314 "3:\n" \
315 _ASM_EXTABLE_TYPE_REG(1b, 3b, EX_TYPE_EFAULT_REG | \
316 EX_FLAG_CLEAR_AX_DX, \
317 %[errout]) \
318 _ASM_EXTABLE_TYPE_REG(2b, 3b, EX_TYPE_EFAULT_REG | \
319 EX_FLAG_CLEAR_AX_DX, \
320 %[errout]) \
321 : [errout] "=r" (retval), \
322 [output] "=&A"(x) \
323 : [lowbits] "m" (__m(__ptr)), \
324 [highbits] "m" __m(((u32 __user *)(__ptr)) + 1), \
325 "0" (retval)); \
326})
327
328#else
329#define __get_user_asm_u64(x, ptr, retval) \
330 __get_user_asm(x, ptr, retval, "q")
331#endif
332
333#define __get_user_size(x, ptr, size, retval) \
334do { \
335 unsigned char x_u8__; \
336 \
337 retval = 0; \
338 __chk_user_ptr(ptr); \
339 switch (size) { \
340 case 1: \
341 __get_user_asm(x_u8__, ptr, retval, "b"); \
342 (x) = x_u8__; \
343 break; \
344 case 2: \
345 __get_user_asm(x, ptr, retval, "w"); \
346 break; \
347 case 4: \
348 __get_user_asm(x, ptr, retval, "l"); \
349 break; \
350 case 8: \
351 __get_user_asm_u64(x, ptr, retval); \
352 break; \
353 default: \
354 (x) = __get_user_bad(); \
355 } \
356} while (0)
357
358#define __get_user_asm(x, addr, err, itype) \
359 asm volatile("\n" \
360 "1: mov"itype" %[umem],%[output]\n" \
361 "2:\n" \
362 _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_EFAULT_REG | \
363 EX_FLAG_CLEAR_AX, \
364 %[errout]) \
365 : [errout] "=r" (err), \
366 [output] "=a" (x) \
367 : [umem] "m" (__m(addr)), \
368 "0" (err))
369
370#endif // CONFIG_CC_HAS_ASM_GOTO_OUTPUT
371
372#ifdef CONFIG_CC_HAS_ASM_GOTO_TIED_OUTPUT
373#define __try_cmpxchg_user_asm(itype, ltype, _ptr, _pold, _new, label) ({ \
374 bool success; \
375 __typeof__(_ptr) _old = (__typeof__(_ptr))(_pold); \
376 __typeof__(*(_ptr)) __old = *_old; \
377 __typeof__(*(_ptr)) __new = (_new); \
378 asm_goto_output("\n" \
379 "1: " LOCK_PREFIX "cmpxchg"itype" %[new], %[ptr]\n"\
380 _ASM_EXTABLE_UA(1b, %l[label]) \
381 : CC_OUT(z) (success), \
382 [ptr] "+m" (*_ptr), \
383 [old] "+a" (__old) \
384 : [new] ltype (__new) \
385 : "memory" \
386 : label); \
387 if (unlikely(!success)) \
388 *_old = __old; \
389 likely(success); })
390
391#ifdef CONFIG_X86_32
392#define __try_cmpxchg64_user_asm(_ptr, _pold, _new, label) ({ \
393 bool success; \
394 __typeof__(_ptr) _old = (__typeof__(_ptr))(_pold); \
395 __typeof__(*(_ptr)) __old = *_old; \
396 __typeof__(*(_ptr)) __new = (_new); \
397 asm_goto_output("\n" \
398 "1: " LOCK_PREFIX "cmpxchg8b %[ptr]\n" \
399 _ASM_EXTABLE_UA(1b, %l[label]) \
400 : CC_OUT(z) (success), \
401 "+A" (__old), \
402 [ptr] "+m" (*_ptr) \
403 : "b" ((u32)__new), \
404 "c" ((u32)((u64)__new >> 32)) \
405 : "memory" \
406 : label); \
407 if (unlikely(!success)) \
408 *_old = __old; \
409 likely(success); })
410#endif // CONFIG_X86_32
411#else // !CONFIG_CC_HAS_ASM_GOTO_TIED_OUTPUT
412#define __try_cmpxchg_user_asm(itype, ltype, _ptr, _pold, _new, label) ({ \
413 int __err = 0; \
414 bool success; \
415 __typeof__(_ptr) _old = (__typeof__(_ptr))(_pold); \
416 __typeof__(*(_ptr)) __old = *_old; \
417 __typeof__(*(_ptr)) __new = (_new); \
418 asm volatile("\n" \
419 "1: " LOCK_PREFIX "cmpxchg"itype" %[new], %[ptr]\n"\
420 CC_SET(z) \
421 "2:\n" \
422 _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_EFAULT_REG, \
423 %[errout]) \
424 : CC_OUT(z) (success), \
425 [errout] "+r" (__err), \
426 [ptr] "+m" (*_ptr), \
427 [old] "+a" (__old) \
428 : [new] ltype (__new) \
429 : "memory"); \
430 if (unlikely(__err)) \
431 goto label; \
432 if (unlikely(!success)) \
433 *_old = __old; \
434 likely(success); })
435
436#ifdef CONFIG_X86_32
437/*
438 * Unlike the normal CMPXCHG, use output GPR for both success/fail and error.
439 * There are only six GPRs available and four (EAX, EBX, ECX, and EDX) are
440 * hardcoded by CMPXCHG8B, leaving only ESI and EDI. If the compiler uses
441 * both ESI and EDI for the memory operand, compilation will fail if the error
442 * is an input+output as there will be no register available for input.
443 */
444#define __try_cmpxchg64_user_asm(_ptr, _pold, _new, label) ({ \
445 int __result; \
446 __typeof__(_ptr) _old = (__typeof__(_ptr))(_pold); \
447 __typeof__(*(_ptr)) __old = *_old; \
448 __typeof__(*(_ptr)) __new = (_new); \
449 asm volatile("\n" \
450 "1: " LOCK_PREFIX "cmpxchg8b %[ptr]\n" \
451 "mov $0, %[result]\n\t" \
452 "setz %b[result]\n" \
453 "2:\n" \
454 _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_EFAULT_REG, \
455 %[result]) \
456 : [result] "=q" (__result), \
457 "+A" (__old), \
458 [ptr] "+m" (*_ptr) \
459 : "b" ((u32)__new), \
460 "c" ((u32)((u64)__new >> 32)) \
461 : "memory", "cc"); \
462 if (unlikely(__result < 0)) \
463 goto label; \
464 if (unlikely(!__result)) \
465 *_old = __old; \
466 likely(__result); })
467#endif // CONFIG_X86_32
468#endif // CONFIG_CC_HAS_ASM_GOTO_TIED_OUTPUT
469
470/* FIXME: this hack is definitely wrong -AK */
471struct __large_struct { unsigned long buf[100]; };
472#define __m(x) (*(struct __large_struct __user *)(x))
473
474/*
475 * Tell gcc we read from memory instead of writing: this is because
476 * we do not write to any memory gcc knows about, so there are no
477 * aliasing issues.
478 */
479#define __put_user_goto(x, addr, itype, ltype, label) \
480 asm goto("\n" \
481 "1: mov"itype" %0,%1\n" \
482 _ASM_EXTABLE_UA(1b, %l2) \
483 : : ltype(x), "m" (__m(addr)) \
484 : : label)
485
486extern unsigned long
487copy_from_user_nmi(void *to, const void __user *from, unsigned long n);
488extern __must_check long
489strncpy_from_user(char *dst, const char __user *src, long count);
490
491extern __must_check long strnlen_user(const char __user *str, long n);
492
493#ifdef CONFIG_ARCH_HAS_COPY_MC
494unsigned long __must_check
495copy_mc_to_kernel(void *to, const void *from, unsigned len);
496#define copy_mc_to_kernel copy_mc_to_kernel
497
498unsigned long __must_check
499copy_mc_to_user(void __user *to, const void *from, unsigned len);
500#endif
501
502/*
503 * movsl can be slow when source and dest are not both 8-byte aligned
504 */
505#ifdef CONFIG_X86_INTEL_USERCOPY
506extern struct movsl_mask {
507 int mask;
508} ____cacheline_aligned_in_smp movsl_mask;
509#endif
510
511#define ARCH_HAS_NOCACHE_UACCESS 1
512
513/*
514 * The "unsafe" user accesses aren't really "unsafe", but the naming
515 * is a big fat warning: you have to not only do the access_ok()
516 * checking before using them, but you have to surround them with the
517 * user_access_begin/end() pair.
518 */
519static __must_check __always_inline bool user_access_begin(const void __user *ptr, size_t len)
520{
521 if (unlikely(!access_ok(ptr,len)))
522 return 0;
523 __uaccess_begin_nospec();
524 return 1;
525}
526#define user_access_begin(a,b) user_access_begin(a,b)
527#define user_access_end() __uaccess_end()
528
529#define user_access_save() smap_save()
530#define user_access_restore(x) smap_restore(x)
531
532#define unsafe_put_user(x, ptr, label) \
533 __put_user_size((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)), label)
534
535#ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT
536#define unsafe_get_user(x, ptr, err_label) \
537do { \
538 __inttype(*(ptr)) __gu_val; \
539 __get_user_size(__gu_val, (ptr), sizeof(*(ptr)), err_label); \
540 (x) = (__force __typeof__(*(ptr)))__gu_val; \
541} while (0)
542#else // !CONFIG_CC_HAS_ASM_GOTO_OUTPUT
543#define unsafe_get_user(x, ptr, err_label) \
544do { \
545 int __gu_err; \
546 __inttype(*(ptr)) __gu_val; \
547 __get_user_size(__gu_val, (ptr), sizeof(*(ptr)), __gu_err); \
548 (x) = (__force __typeof__(*(ptr)))__gu_val; \
549 if (unlikely(__gu_err)) goto err_label; \
550} while (0)
551#endif // CONFIG_CC_HAS_ASM_GOTO_OUTPUT
552
553extern void __try_cmpxchg_user_wrong_size(void);
554
555#ifndef CONFIG_X86_32
556#define __try_cmpxchg64_user_asm(_ptr, _oldp, _nval, _label) \
557 __try_cmpxchg_user_asm("q", "r", (_ptr), (_oldp), (_nval), _label)
558#endif
559
560/*
561 * Force the pointer to u<size> to match the size expected by the asm helper.
562 * clang/LLVM compiles all cases and only discards the unused paths after
563 * processing errors, which breaks i386 if the pointer is an 8-byte value.
564 */
565#define unsafe_try_cmpxchg_user(_ptr, _oldp, _nval, _label) ({ \
566 bool __ret; \
567 __chk_user_ptr(_ptr); \
568 switch (sizeof(*(_ptr))) { \
569 case 1: __ret = __try_cmpxchg_user_asm("b", "q", \
570 (__force u8 *)(_ptr), (_oldp), \
571 (_nval), _label); \
572 break; \
573 case 2: __ret = __try_cmpxchg_user_asm("w", "r", \
574 (__force u16 *)(_ptr), (_oldp), \
575 (_nval), _label); \
576 break; \
577 case 4: __ret = __try_cmpxchg_user_asm("l", "r", \
578 (__force u32 *)(_ptr), (_oldp), \
579 (_nval), _label); \
580 break; \
581 case 8: __ret = __try_cmpxchg64_user_asm((__force u64 *)(_ptr), (_oldp),\
582 (_nval), _label); \
583 break; \
584 default: __try_cmpxchg_user_wrong_size(); \
585 } \
586 __ret; })
587
588/* "Returns" 0 on success, 1 on failure, -EFAULT if the access faults. */
589#define __try_cmpxchg_user(_ptr, _oldp, _nval, _label) ({ \
590 int __ret = -EFAULT; \
591 __uaccess_begin_nospec(); \
592 __ret = !unsafe_try_cmpxchg_user(_ptr, _oldp, _nval, _label); \
593_label: \
594 __uaccess_end(); \
595 __ret; \
596 })
597
598/*
599 * We want the unsafe accessors to always be inlined and use
600 * the error labels - thus the macro games.
601 */
602#define unsafe_copy_loop(dst, src, len, type, label) \
603 while (len >= sizeof(type)) { \
604 unsafe_put_user(*(type *)(src),(type __user *)(dst),label); \
605 dst += sizeof(type); \
606 src += sizeof(type); \
607 len -= sizeof(type); \
608 }
609
610#define unsafe_copy_to_user(_dst,_src,_len,label) \
611do { \
612 char __user *__ucu_dst = (_dst); \
613 const char *__ucu_src = (_src); \
614 size_t __ucu_len = (_len); \
615 unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u64, label); \
616 unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u32, label); \
617 unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u16, label); \
618 unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u8, label); \
619} while (0)
620
621#ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT
622#define __get_kernel_nofault(dst, src, type, err_label) \
623 __get_user_size(*((type *)(dst)), (__force type __user *)(src), \
624 sizeof(type), err_label)
625#else // !CONFIG_CC_HAS_ASM_GOTO_OUTPUT
626#define __get_kernel_nofault(dst, src, type, err_label) \
627do { \
628 int __kr_err; \
629 \
630 __get_user_size(*((type *)(dst)), (__force type __user *)(src), \
631 sizeof(type), __kr_err); \
632 if (unlikely(__kr_err)) \
633 goto err_label; \
634} while (0)
635#endif // CONFIG_CC_HAS_ASM_GOTO_OUTPUT
636
637#define __put_kernel_nofault(dst, src, type, err_label) \
638 __put_user_size(*((type *)(src)), (__force type __user *)(dst), \
639 sizeof(type), err_label)
640
641#endif /* _ASM_X86_UACCESS_H */
642
643

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source code of linux/arch/x86/include/asm/uaccess.h