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1 | /* SPDX-License-Identifier: GPL-2.0 */ | |
2 | #ifndef _ARCH_POWERPC_UACCESS_H | |
3 | #define _ARCH_POWERPC_UACCESS_H | |
4 | ||
5 | #include <asm/processor.h> | |
6 | #include <asm/page.h> | |
7 | #include <asm/extable.h> | |
8 | #include <asm/kup.h> | |
9 | #include <asm/asm-compat.h> | |
10 | ||
11 | #ifdef __powerpc64__ | |
12 | /* We use TASK_SIZE_USER64 as TASK_SIZE is not constant */ | |
13 | #define TASK_SIZE_MAX TASK_SIZE_USER64 | |
14 | #endif | |
15 | ||
16 | #include <asm-generic/access_ok.h> | |
17 | ||
18 | /* | |
19 | * These are the main single-value transfer routines. They automatically | |
20 | * use the right size if we just have the right pointer type. | |
21 | * | |
22 | * This gets kind of ugly. We want to return _two_ values in "get_user()" | |
23 | * and yet we don't want to do any pointers, because that is too much | |
24 | * of a performance impact. Thus we have a few rather ugly macros here, | |
25 | * and hide all the ugliness from the user. | |
26 | * | |
27 | * The "__xxx" versions of the user access functions are versions that | |
28 | * do not verify the address space, that must have been done previously | |
29 | * with a separate "access_ok()" call (this is used when we do multiple | |
30 | * accesses to the same area of user memory). | |
31 | * | |
32 | * As we use the same address space for kernel and user data on the | |
33 | * PowerPC, we can just do these as direct assignments. (Of course, the | |
34 | * exception handling means that it's no longer "just"...) | |
35 | * | |
36 | */ | |
37 | #define __put_user(x, ptr) \ | |
38 | ({ \ | |
39 | long __pu_err; \ | |
40 | __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ | |
41 | __typeof__(*(ptr)) __pu_val = (__typeof__(*(ptr)))(x); \ | |
42 | __typeof__(sizeof(*(ptr))) __pu_size = sizeof(*(ptr)); \ | |
43 | \ | |
44 | might_fault(); \ | |
45 | do { \ | |
46 | __label__ __pu_failed; \ | |
47 | \ | |
48 | allow_write_to_user(__pu_addr, __pu_size); \ | |
49 | __put_user_size_goto(__pu_val, __pu_addr, __pu_size, __pu_failed); \ | |
50 | prevent_write_to_user(__pu_addr, __pu_size); \ | |
51 | __pu_err = 0; \ | |
52 | break; \ | |
53 | \ | |
54 | __pu_failed: \ | |
55 | prevent_write_to_user(__pu_addr, __pu_size); \ | |
56 | __pu_err = -EFAULT; \ | |
57 | } while (0); \ | |
58 | \ | |
59 | __pu_err; \ | |
60 | }) | |
61 | ||
62 | #define put_user(x, ptr) \ | |
63 | ({ \ | |
64 | __typeof__(*(ptr)) __user *_pu_addr = (ptr); \ | |
65 | \ | |
66 | access_ok(_pu_addr, sizeof(*(ptr))) ? \ | |
67 | __put_user(x, _pu_addr) : -EFAULT; \ | |
68 | }) | |
69 | ||
70 | /* | |
71 | * We don't tell gcc that we are accessing memory, but this is OK | |
72 | * because we do not write to any memory gcc knows about, so there | |
73 | * are no aliasing issues. | |
74 | */ | |
75 | /* -mprefixed can generate offsets beyond range, fall back hack */ | |
76 | #ifdef CONFIG_PPC_KERNEL_PREFIXED | |
77 | #define __put_user_asm_goto(x, addr, label, op) \ | |
78 | asm goto( \ | |
79 | "1: " op " %0,0(%1) # put_user\n" \ | |
80 | EX_TABLE(1b, %l2) \ | |
81 | : \ | |
82 | : "r" (x), "b" (addr) \ | |
83 | : \ | |
84 | : label) | |
85 | #else | |
86 | #define __put_user_asm_goto(x, addr, label, op) \ | |
87 | asm goto( \ | |
88 | "1: " op "%U1%X1 %0,%1 # put_user\n" \ | |
89 | EX_TABLE(1b, %l2) \ | |
90 | : \ | |
91 | : "r" (x), "m<>" (*addr) \ | |
92 | : \ | |
93 | : label) | |
94 | #endif | |
95 | ||
96 | #ifdef __powerpc64__ | |
97 | #ifdef CONFIG_PPC_KERNEL_PREFIXED | |
98 | #define __put_user_asm2_goto(x, ptr, label) \ | |
99 | __put_user_asm_goto(x, ptr, label, "std") | |
100 | #else | |
101 | #define __put_user_asm2_goto(x, addr, label) \ | |
102 | asm goto ("1: std%U1%X1 %0,%1 # put_user\n" \ | |
103 | EX_TABLE(1b, %l2) \ | |
104 | : \ | |
105 | : "r" (x), DS_FORM_CONSTRAINT (*addr) \ | |
106 | : \ | |
107 | : label) | |
108 | #endif // CONFIG_PPC_KERNEL_PREFIXED | |
109 | #else /* __powerpc64__ */ | |
110 | #define __put_user_asm2_goto(x, addr, label) \ | |
111 | asm goto( \ | |
112 | "1: stw%X1 %0, %1\n" \ | |
113 | "2: stw%X1 %L0, %L1\n" \ | |
114 | EX_TABLE(1b, %l2) \ | |
115 | EX_TABLE(2b, %l2) \ | |
116 | : \ | |
117 | : "r" (x), "m" (*addr) \ | |
118 | : \ | |
119 | : label) | |
120 | #endif /* __powerpc64__ */ | |
121 | ||
122 | #define __put_user_size_goto(x, ptr, size, label) \ | |
123 | do { \ | |
124 | __typeof__(*(ptr)) __user *__pus_addr = (ptr); \ | |
125 | \ | |
126 | switch (size) { \ | |
127 | case 1: __put_user_asm_goto(x, __pus_addr, label, "stb"); break; \ | |
128 | case 2: __put_user_asm_goto(x, __pus_addr, label, "sth"); break; \ | |
129 | case 4: __put_user_asm_goto(x, __pus_addr, label, "stw"); break; \ | |
130 | case 8: __put_user_asm2_goto(x, __pus_addr, label); break; \ | |
131 | default: BUILD_BUG(); \ | |
132 | } \ | |
133 | } while (0) | |
134 | ||
135 | /* | |
136 | * This does an atomic 128 byte aligned load from userspace. | |
137 | * Upto caller to do enable_kernel_vmx() before calling! | |
138 | */ | |
139 | #define __get_user_atomic_128_aligned(kaddr, uaddr, err) \ | |
140 | __asm__ __volatile__( \ | |
141 | ".machine push\n" \ | |
142 | ".machine altivec\n" \ | |
143 | "1: lvx 0,0,%1 # get user\n" \ | |
144 | " stvx 0,0,%2 # put kernel\n" \ | |
145 | ".machine pop\n" \ | |
146 | "2:\n" \ | |
147 | ".section .fixup,\"ax\"\n" \ | |
148 | "3: li %0,%3\n" \ | |
149 | " b 2b\n" \ | |
150 | ".previous\n" \ | |
151 | EX_TABLE(1b, 3b) \ | |
152 | : "=r" (err) \ | |
153 | : "b" (uaddr), "b" (kaddr), "i" (-EFAULT), "0" (err)) | |
154 | ||
155 | #ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT | |
156 | ||
157 | /* -mprefixed can generate offsets beyond range, fall back hack */ | |
158 | #ifdef CONFIG_PPC_KERNEL_PREFIXED | |
159 | #define __get_user_asm_goto(x, addr, label, op) \ | |
160 | asm_goto_output( \ | |
161 | "1: "op" %0,0(%1) # get_user\n" \ | |
162 | EX_TABLE(1b, %l2) \ | |
163 | : "=r" (x) \ | |
164 | : "b" (addr) \ | |
165 | : \ | |
166 | : label) | |
167 | #else | |
168 | #define __get_user_asm_goto(x, addr, label, op) \ | |
169 | asm_goto_output( \ | |
170 | "1: "op"%U1%X1 %0, %1 # get_user\n" \ | |
171 | EX_TABLE(1b, %l2) \ | |
172 | : "=r" (x) \ | |
173 | : "m<>" (*addr) \ | |
174 | : \ | |
175 | : label) | |
176 | #endif | |
177 | ||
178 | #ifdef __powerpc64__ | |
179 | #ifdef CONFIG_PPC_KERNEL_PREFIXED | |
180 | #define __get_user_asm2_goto(x, addr, label) \ | |
181 | __get_user_asm_goto(x, addr, label, "ld") | |
182 | #else | |
183 | #define __get_user_asm2_goto(x, addr, label) \ | |
184 | asm_goto_output( \ | |
185 | "1: ld%U1%X1 %0, %1 # get_user\n" \ | |
186 | EX_TABLE(1b, %l2) \ | |
187 | : "=r" (x) \ | |
188 | : DS_FORM_CONSTRAINT (*addr) \ | |
189 | : \ | |
190 | : label) | |
191 | #endif // CONFIG_PPC_KERNEL_PREFIXED | |
192 | #else /* __powerpc64__ */ | |
193 | #define __get_user_asm2_goto(x, addr, label) \ | |
194 | asm_goto_output( \ | |
195 | "1: lwz%X1 %0, %1\n" \ | |
196 | "2: lwz%X1 %L0, %L1\n" \ | |
197 | EX_TABLE(1b, %l2) \ | |
198 | EX_TABLE(2b, %l2) \ | |
199 | : "=&r" (x) \ | |
200 | : "m" (*addr) \ | |
201 | : \ | |
202 | : label) | |
203 | #endif /* __powerpc64__ */ | |
204 | ||
205 | #define __get_user_size_goto(x, ptr, size, label) \ | |
206 | do { \ | |
207 | BUILD_BUG_ON(size > sizeof(x)); \ | |
208 | switch (size) { \ | |
209 | case 1: __get_user_asm_goto(x, (u8 __user *)ptr, label, "lbz"); break; \ | |
210 | case 2: __get_user_asm_goto(x, (u16 __user *)ptr, label, "lhz"); break; \ | |
211 | case 4: __get_user_asm_goto(x, (u32 __user *)ptr, label, "lwz"); break; \ | |
212 | case 8: __get_user_asm2_goto(x, (u64 __user *)ptr, label); break; \ | |
213 | default: x = 0; BUILD_BUG(); \ | |
214 | } \ | |
215 | } while (0) | |
216 | ||
217 | #define __get_user_size_allowed(x, ptr, size, retval) \ | |
218 | do { \ | |
219 | __label__ __gus_failed; \ | |
220 | \ | |
221 | __get_user_size_goto(x, ptr, size, __gus_failed); \ | |
222 | retval = 0; \ | |
223 | break; \ | |
224 | __gus_failed: \ | |
225 | x = 0; \ | |
226 | retval = -EFAULT; \ | |
227 | } while (0) | |
228 | ||
229 | #else /* CONFIG_CC_HAS_ASM_GOTO_OUTPUT */ | |
230 | ||
231 | #define __get_user_asm(x, addr, err, op) \ | |
232 | __asm__ __volatile__( \ | |
233 | "1: "op"%U2%X2 %1, %2 # get_user\n" \ | |
234 | "2:\n" \ | |
235 | ".section .fixup,\"ax\"\n" \ | |
236 | "3: li %0,%3\n" \ | |
237 | " li %1,0\n" \ | |
238 | " b 2b\n" \ | |
239 | ".previous\n" \ | |
240 | EX_TABLE(1b, 3b) \ | |
241 | : "=r" (err), "=r" (x) \ | |
242 | : "m<>" (*addr), "i" (-EFAULT), "0" (err)) | |
243 | ||
244 | #ifdef __powerpc64__ | |
245 | #define __get_user_asm2(x, addr, err) \ | |
246 | __get_user_asm(x, addr, err, "ld") | |
247 | #else /* __powerpc64__ */ | |
248 | #define __get_user_asm2(x, addr, err) \ | |
249 | __asm__ __volatile__( \ | |
250 | "1: lwz%X2 %1, %2\n" \ | |
251 | "2: lwz%X2 %L1, %L2\n" \ | |
252 | "3:\n" \ | |
253 | ".section .fixup,\"ax\"\n" \ | |
254 | "4: li %0,%3\n" \ | |
255 | " li %1,0\n" \ | |
256 | " li %1+1,0\n" \ | |
257 | " b 3b\n" \ | |
258 | ".previous\n" \ | |
259 | EX_TABLE(1b, 4b) \ | |
260 | EX_TABLE(2b, 4b) \ | |
261 | : "=r" (err), "=&r" (x) \ | |
262 | : "m" (*addr), "i" (-EFAULT), "0" (err)) | |
263 | #endif /* __powerpc64__ */ | |
264 | ||
265 | #define __get_user_size_allowed(x, ptr, size, retval) \ | |
266 | do { \ | |
267 | retval = 0; \ | |
268 | BUILD_BUG_ON(size > sizeof(x)); \ | |
269 | switch (size) { \ | |
270 | case 1: __get_user_asm(x, (u8 __user *)ptr, retval, "lbz"); break; \ | |
271 | case 2: __get_user_asm(x, (u16 __user *)ptr, retval, "lhz"); break; \ | |
272 | case 4: __get_user_asm(x, (u32 __user *)ptr, retval, "lwz"); break; \ | |
273 | case 8: __get_user_asm2(x, (u64 __user *)ptr, retval); break; \ | |
274 | default: x = 0; BUILD_BUG(); \ | |
275 | } \ | |
276 | } while (0) | |
277 | ||
278 | #define __get_user_size_goto(x, ptr, size, label) \ | |
279 | do { \ | |
280 | long __gus_retval; \ | |
281 | \ | |
282 | __get_user_size_allowed(x, ptr, size, __gus_retval); \ | |
283 | if (__gus_retval) \ | |
284 | goto label; \ | |
285 | } while (0) | |
286 | ||
287 | #endif /* CONFIG_CC_HAS_ASM_GOTO_OUTPUT */ | |
288 | ||
289 | /* | |
290 | * This is a type: either unsigned long, if the argument fits into | |
291 | * that type, or otherwise unsigned long long. | |
292 | */ | |
293 | #define __long_type(x) \ | |
294 | __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL)) | |
295 | ||
296 | #define __get_user(x, ptr) \ | |
297 | ({ \ | |
298 | long __gu_err; \ | |
299 | __long_type(*(ptr)) __gu_val; \ | |
300 | __typeof__(*(ptr)) __user *__gu_addr = (ptr); \ | |
301 | __typeof__(sizeof(*(ptr))) __gu_size = sizeof(*(ptr)); \ | |
302 | \ | |
303 | might_fault(); \ | |
304 | allow_read_from_user(__gu_addr, __gu_size); \ | |
305 | __get_user_size_allowed(__gu_val, __gu_addr, __gu_size, __gu_err); \ | |
306 | prevent_read_from_user(__gu_addr, __gu_size); \ | |
307 | (x) = (__typeof__(*(ptr)))__gu_val; \ | |
308 | \ | |
309 | __gu_err; \ | |
310 | }) | |
311 | ||
312 | #define get_user(x, ptr) \ | |
313 | ({ \ | |
314 | __typeof__(*(ptr)) __user *_gu_addr = (ptr); \ | |
315 | \ | |
316 | access_ok(_gu_addr, sizeof(*(ptr))) ? \ | |
317 | __get_user(x, _gu_addr) : \ | |
318 | ((x) = (__force __typeof__(*(ptr)))0, -EFAULT); \ | |
319 | }) | |
320 | ||
321 | /* more complex routines */ | |
322 | ||
323 | extern unsigned long __copy_tofrom_user(void __user *to, | |
324 | const void __user *from, unsigned long size); | |
325 | ||
326 | #ifdef __powerpc64__ | |
327 | static inline unsigned long | |
328 | raw_copy_in_user(void __user *to, const void __user *from, unsigned long n) | |
329 | { | |
330 | unsigned long ret; | |
331 | ||
332 | allow_read_write_user(to, from, n); | |
333 | ret = __copy_tofrom_user(to, from, n); | |
334 | prevent_read_write_user(to, from, n); | |
335 | return ret; | |
336 | } | |
337 | #endif /* __powerpc64__ */ | |
338 | ||
339 | static inline unsigned long raw_copy_from_user(void *to, | |
340 | const void __user *from, unsigned long n) | |
341 | { | |
342 | unsigned long ret; | |
343 | ||
344 | allow_read_from_user(from, n); | |
345 | ret = __copy_tofrom_user((__force void __user *)to, from, n); | |
346 | prevent_read_from_user(from, n); | |
347 | return ret; | |
348 | } | |
349 | ||
350 | static inline unsigned long | |
351 | raw_copy_to_user(void __user *to, const void *from, unsigned long n) | |
352 | { | |
353 | unsigned long ret; | |
354 | ||
355 | allow_write_to_user(to, n); | |
356 | ret = __copy_tofrom_user(to, (__force const void __user *)from, n); | |
357 | prevent_write_to_user(to, n); | |
358 | return ret; | |
359 | } | |
360 | ||
361 | unsigned long __arch_clear_user(void __user *addr, unsigned long size); | |
362 | ||
363 | static inline unsigned long __clear_user(void __user *addr, unsigned long size) | |
364 | { | |
365 | unsigned long ret; | |
366 | ||
367 | might_fault(); | |
368 | allow_write_to_user(addr, size); | |
369 | ret = __arch_clear_user(addr, size); | |
370 | prevent_write_to_user(addr, size); | |
371 | return ret; | |
372 | } | |
373 | ||
374 | static inline unsigned long clear_user(void __user *addr, unsigned long size) | |
375 | { | |
376 | return likely(access_ok(addr, size)) ? __clear_user(addr, size) : size; | |
377 | } | |
378 | ||
379 | extern long strncpy_from_user(char *dst, const char __user *src, long count); | |
380 | extern __must_check long strnlen_user(const char __user *str, long n); | |
381 | ||
382 | #ifdef CONFIG_ARCH_HAS_COPY_MC | |
383 | unsigned long __must_check | |
384 | copy_mc_generic(void *to, const void *from, unsigned long size); | |
385 | ||
386 | static inline unsigned long __must_check | |
387 | copy_mc_to_kernel(void *to, const void *from, unsigned long size) | |
388 | { | |
389 | return copy_mc_generic(to, from, size); | |
390 | } | |
391 | #define copy_mc_to_kernel copy_mc_to_kernel | |
392 | ||
393 | static inline unsigned long __must_check | |
394 | copy_mc_to_user(void __user *to, const void *from, unsigned long n) | |
395 | { | |
396 | if (check_copy_size(from, n, true)) { | |
397 | if (access_ok(to, n)) { | |
398 | allow_write_to_user(to, n); | |
399 | n = copy_mc_generic((void __force *)to, from, n); | |
400 | prevent_write_to_user(to, n); | |
401 | } | |
402 | } | |
403 | ||
404 | return n; | |
405 | } | |
406 | #endif | |
407 | ||
408 | extern long __copy_from_user_flushcache(void *dst, const void __user *src, | |
409 | unsigned size); | |
410 | ||
411 | static __must_check __always_inline bool user_access_begin(const void __user *ptr, size_t len) | |
412 | { | |
413 | if (unlikely(!access_ok(ptr, len))) | |
414 | return false; | |
415 | ||
416 | might_fault(); | |
417 | ||
418 | allow_read_write_user((void __user *)ptr, ptr, len); | |
419 | return true; | |
420 | } | |
421 | #define user_access_begin user_access_begin | |
422 | #define user_access_end prevent_current_access_user | |
423 | #define user_access_save prevent_user_access_return | |
424 | #define user_access_restore restore_user_access | |
425 | ||
426 | static __must_check __always_inline bool | |
427 | user_read_access_begin(const void __user *ptr, size_t len) | |
428 | { | |
429 | if (unlikely(!access_ok(ptr, len))) | |
430 | return false; | |
431 | ||
432 | might_fault(); | |
433 | ||
434 | allow_read_from_user(ptr, len); | |
435 | return true; | |
436 | } | |
437 | #define user_read_access_begin user_read_access_begin | |
438 | #define user_read_access_end prevent_current_read_from_user | |
439 | ||
440 | static __must_check __always_inline bool | |
441 | user_write_access_begin(const void __user *ptr, size_t len) | |
442 | { | |
443 | if (unlikely(!access_ok(ptr, len))) | |
444 | return false; | |
445 | ||
446 | might_fault(); | |
447 | ||
448 | allow_write_to_user((void __user *)ptr, len); | |
449 | return true; | |
450 | } | |
451 | #define user_write_access_begin user_write_access_begin | |
452 | #define user_write_access_end prevent_current_write_to_user | |
453 | ||
454 | #define unsafe_get_user(x, p, e) do { \ | |
455 | __long_type(*(p)) __gu_val; \ | |
456 | __typeof__(*(p)) __user *__gu_addr = (p); \ | |
457 | \ | |
458 | __get_user_size_goto(__gu_val, __gu_addr, sizeof(*(p)), e); \ | |
459 | (x) = (__typeof__(*(p)))__gu_val; \ | |
460 | } while (0) | |
461 | ||
462 | #define unsafe_put_user(x, p, e) \ | |
463 | __put_user_size_goto((__typeof__(*(p)))(x), (p), sizeof(*(p)), e) | |
464 | ||
465 | #define unsafe_copy_from_user(d, s, l, e) \ | |
466 | do { \ | |
467 | u8 *_dst = (u8 *)(d); \ | |
468 | const u8 __user *_src = (const u8 __user *)(s); \ | |
469 | size_t _len = (l); \ | |
470 | int _i; \ | |
471 | \ | |
472 | for (_i = 0; _i < (_len & ~(sizeof(u64) - 1)); _i += sizeof(u64)) \ | |
473 | unsafe_get_user(*(u64 *)(_dst + _i), (u64 __user *)(_src + _i), e); \ | |
474 | if (_len & 4) { \ | |
475 | unsafe_get_user(*(u32 *)(_dst + _i), (u32 __user *)(_src + _i), e); \ | |
476 | _i += 4; \ | |
477 | } \ | |
478 | if (_len & 2) { \ | |
479 | unsafe_get_user(*(u16 *)(_dst + _i), (u16 __user *)(_src + _i), e); \ | |
480 | _i += 2; \ | |
481 | } \ | |
482 | if (_len & 1) \ | |
483 | unsafe_get_user(*(u8 *)(_dst + _i), (u8 __user *)(_src + _i), e); \ | |
484 | } while (0) | |
485 | ||
486 | #define unsafe_copy_to_user(d, s, l, e) \ | |
487 | do { \ | |
488 | u8 __user *_dst = (u8 __user *)(d); \ | |
489 | const u8 *_src = (const u8 *)(s); \ | |
490 | size_t _len = (l); \ | |
491 | int _i; \ | |
492 | \ | |
493 | for (_i = 0; _i < (_len & ~(sizeof(u64) - 1)); _i += sizeof(u64)) \ | |
494 | unsafe_put_user(*(u64 *)(_src + _i), (u64 __user *)(_dst + _i), e); \ | |
495 | if (_len & 4) { \ | |
496 | unsafe_put_user(*(u32*)(_src + _i), (u32 __user *)(_dst + _i), e); \ | |
497 | _i += 4; \ | |
498 | } \ | |
499 | if (_len & 2) { \ | |
500 | unsafe_put_user(*(u16*)(_src + _i), (u16 __user *)(_dst + _i), e); \ | |
501 | _i += 2; \ | |
502 | } \ | |
503 | if (_len & 1) \ | |
504 | unsafe_put_user(*(u8*)(_src + _i), (u8 __user *)(_dst + _i), e); \ | |
505 | } while (0) | |
506 | ||
507 | #define __get_kernel_nofault(dst, src, type, err_label) \ | |
508 | __get_user_size_goto(*((type *)(dst)), \ | |
509 | (__force type __user *)(src), sizeof(type), err_label) | |
510 | ||
511 | #define __put_kernel_nofault(dst, src, type, err_label) \ | |
512 | __put_user_size_goto(*((type *)(src)), \ | |
513 | (__force type __user *)(dst), sizeof(type), err_label) | |
514 | ||
515 | #endif /* _ARCH_POWERPC_UACCESS_H */ |