1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
|
// SPDX-License-Identifier: GPL-2.0
/*
* User address space access functions.
* The non inlined parts of asm-i386/uaccess.h are here.
*
* Copyright 1997 Andi Kleen <ak@muc.de>
* Copyright 1997 Linus Torvalds
*/
#include <linux/export.h>
#include <linux/uaccess.h>
#include <asm/mmx.h>
#include <asm/asm.h>
#ifdef CONFIG_X86_INTEL_USERCOPY
/*
* Alignment at which movsl is preferred for bulk memory copies.
*/
struct movsl_mask movsl_mask __read_mostly;
#endif
static inline int __movsl_is_ok(unsigned long a1, unsigned long a2, unsigned long n)
{
#ifdef CONFIG_X86_INTEL_USERCOPY
if (n >= 64 && ((a1 ^ a2) & movsl_mask.mask))
return 0;
#endif
return 1;
}
#define movsl_is_ok(a1, a2, n) \
__movsl_is_ok((unsigned long)(a1), (unsigned long)(a2), (n))
/*
* Zero Userspace
*/
#define __do_clear_user(addr,size) \
do { \
int __d0; \
might_fault(); \
__asm__ __volatile__( \
ASM_STAC "\n" \
"0: rep; stosl\n" \
" movl %2,%0\n" \
"1: rep; stosb\n" \
"2: " ASM_CLAC "\n" \
".section .fixup,\"ax\"\n" \
"3: lea 0(%2,%0,4),%0\n" \
" jmp 2b\n" \
".previous\n" \
_ASM_EXTABLE_UA(0b, 3b) \
_ASM_EXTABLE_UA(1b, 2b) \
: "=&c"(size), "=&D" (__d0) \
: "r"(size & 3), "0"(size / 4), "1"(addr), "a"(0)); \
} while (0)
/**
* clear_user: - Zero a block of memory in user space.
* @to: Destination address, in user space.
* @n: Number of bytes to zero.
*
* Zero a block of memory in user space.
*
* Returns number of bytes that could not be cleared.
* On success, this will be zero.
*/
unsigned long
clear_user(void __user *to, unsigned long n)
{
might_fault();
if (access_ok(VERIFY_WRITE, to, n))
__do_clear_user(to, n);
return n;
}
EXPORT_SYMBOL(clear_user);
/**
* __clear_user: - Zero a block of memory in user space, with less checking.
* @to: Destination address, in user space.
* @n: Number of bytes to zero.
*
* Zero a block of memory in user space. Caller must check
* the specified block with access_ok() before calling this function.
*
* Returns number of bytes that could not be cleared.
* On success, this will be zero.
*/
unsigned long
__clear_user(void __user *to, unsigned long n)
{
__do_clear_user(to, n);
return n;
}
EXPORT_SYMBOL(__clear_user);
#ifdef CONFIG_X86_INTEL_USERCOPY
static unsigned long
__copy_user_intel(void __user *to, const void *from, unsigned long size)
{
int d0, d1;
__asm__ __volatile__(
" .align 2,0x90\n"
"1: movl 32(%4), %%eax\n"
" cmpl $67, %0\n"
" jbe 3f\n"
"2: movl 64(%4), %%eax\n"
" .align 2,0x90\n"
"3: movl 0(%4), %%eax\n"
"4: movl 4(%4), %%edx\n"
"5: movl %%eax, 0(%3)\n"
"6: movl %%edx, 4(%3)\n"
"7: movl 8(%4), %%eax\n"
"8: movl 12(%4),%%edx\n"
"9: movl %%eax, 8(%3)\n"
"10: movl %%edx, 12(%3)\n"
"11: movl 16(%4), %%eax\n"
"12: movl 20(%4), %%edx\n"
"13: movl %%eax, 16(%3)\n"
"14: movl %%edx, 20(%3)\n"
"15: movl 24(%4), %%eax\n"
"16: movl 28(%4), %%edx\n"
"17: movl %%eax, 24(%3)\n"
"18: movl %%edx, 28(%3)\n"
"19: movl 32(%4), %%eax\n"
"20: movl 36(%4), %%edx\n"
"21: movl %%eax, 32(%3)\n"
"22: movl %%edx, 36(%3)\n"
"23: movl 40(%4), %%eax\n"
"24: movl 44(%4), %%edx\n"
"25: movl %%eax, 40(%3)\n"
"26: movl %%edx, 44(%3)\n"
"27: movl 48(%4), %%eax\n"
"28: movl 52(%4), %%edx\n"
"29: movl %%eax, 48(%3)\n"
"30: movl %%edx, 52(%3)\n"
"31: movl 56(%4), %%eax\n"
"32: movl 60(%4), %%edx\n"
"33: movl %%eax, 56(%3)\n"
"34: movl %%edx, 60(%3)\n"
" addl $-64, %0\n"
" addl $64, %4\n"
" addl $64, %3\n"
" cmpl $63, %0\n"
" ja 1b\n"
"35: movl %0, %%eax\n"
" shrl $2, %0\n"
" andl $3, %%eax\n"
" cld\n"
"99: rep; movsl\n"
"36: movl %%eax, %0\n"
"37: rep; movsb\n"
"100:\n"
".section .fixup,\"ax\"\n"
"101: lea 0(%%eax,%0,4),%0\n"
" jmp 100b\n"
".previous\n"
_ASM_EXTABLE_UA(1b, 100b)
_ASM_EXTABLE_UA(2b, 100b)
_ASM_EXTABLE_UA(3b, 100b)
_ASM_EXTABLE_UA(4b, 100b)
_ASM_EXTABLE_UA(5b, 100b)
_ASM_EXTABLE_UA(6b, 100b)
_ASM_EXTABLE_UA(7b, 100b)
_ASM_EXTABLE_UA(8b, 100b)
_ASM_EXTABLE_UA(9b, 100b)
_ASM_EXTABLE_UA(10b, 100b)
_ASM_EXTABLE_UA(11b, 100b)
_ASM_EXTABLE_UA(12b, 100b)
_ASM_EXTABLE_UA(13b, 100b)
_ASM_EXTABLE_UA(14b, 100b)
_ASM_EXTABLE_UA(15b, 100b)
_ASM_EXTABLE_UA(16b, 100b)
_ASM_EXTABLE_UA(17b, 100b)
_ASM_EXTABLE_UA(18b, 100b)
_ASM_EXTABLE_UA(19b, 100b)
_ASM_EXTABLE_UA(20b, 100b)
_ASM_EXTABLE_UA(21b, 100b)
_ASM_EXTABLE_UA(22b, 100b)
_ASM_EXTABLE_UA(23b, 100b)
_ASM_EXTABLE_UA(24b, 100b)
_ASM_EXTABLE_UA(25b, 100b)
_ASM_EXTABLE_UA(26b, 100b)
_ASM_EXTABLE_UA(27b, 100b)
_ASM_EXTABLE_UA(28b, 100b)
_ASM_EXTABLE_UA(29b, 100b)
_ASM_EXTABLE_UA(30b, 100b)
_ASM_EXTABLE_UA(31b, 100b)
_ASM_EXTABLE_UA(32b, 100b)
_ASM_EXTABLE_UA(33b, 100b)
_ASM_EXTABLE_UA(34b, 100b)
_ASM_EXTABLE_UA(35b, 100b)
_ASM_EXTABLE_UA(36b, 100b)
_ASM_EXTABLE_UA(37b, 100b)
_ASM_EXTABLE_UA(99b, 101b)
: "=&c"(size), "=&D" (d0), "=&S" (d1)
: "1"(to), "2"(from), "0"(size)
: "eax", "edx", "memory");
return size;
}
static unsigned long __copy_user_intel_nocache(void *to,
const void __user *from, unsigned long size)
{
int d0, d1;
__asm__ __volatile__(
" .align 2,0x90\n"
"0: movl 32(%4), %%eax\n"
" cmpl $67, %0\n"
" jbe 2f\n"
"1: movl 64(%4), %%eax\n"
" .align 2,0x90\n"
"2: movl 0(%4), %%eax\n"
"21: movl 4(%4), %%edx\n"
" movnti %%eax, 0(%3)\n"
" movnti %%edx, 4(%3)\n"
"3: movl 8(%4), %%eax\n"
"31: movl 12(%4),%%edx\n"
" movnti %%eax, 8(%3)\n"
" movnti %%edx, 12(%3)\n"
"4: movl 16(%4), %%eax\n"
"41: movl 20(%4), %%edx\n"
" movnti %%eax, 16(%3)\n"
" movnti %%edx, 20(%3)\n"
"10: movl 24(%4), %%eax\n"
"51: movl 28(%4), %%edx\n"
" movnti %%eax, 24(%3)\n"
" movnti %%edx, 28(%3)\n"
"11: movl 32(%4), %%eax\n"
"61: movl 36(%4), %%edx\n"
" movnti %%eax, 32(%3)\n"
" movnti %%edx, 36(%3)\n"
"12: movl 40(%4), %%eax\n"
"71: movl 44(%4), %%edx\n"
" movnti %%eax, 40(%3)\n"
" movnti %%edx, 44(%3)\n"
"13: movl 48(%4), %%eax\n"
"81: movl 52(%4), %%edx\n"
" movnti %%eax, 48(%3)\n"
" movnti %%edx, 52(%3)\n"
"14: movl 56(%4), %%eax\n"
"91: movl 60(%4), %%edx\n"
" movnti %%eax, 56(%3)\n"
" movnti %%edx, 60(%3)\n"
" addl $-64, %0\n"
" addl $64, %4\n"
" addl $64, %3\n"
" cmpl $63, %0\n"
" ja 0b\n"
" sfence \n"
"5: movl %0, %%eax\n"
" shrl $2, %0\n"
" andl $3, %%eax\n"
" cld\n"
"6: rep; movsl\n"
" movl %%eax,%0\n"
"7: rep; movsb\n"
"8:\n"
".section .fixup,\"ax\"\n"
"9: lea 0(%%eax,%0,4),%0\n"
"16: jmp 8b\n"
".previous\n"
_ASM_EXTABLE_UA(0b, 16b)
_ASM_EXTABLE_UA(1b, 16b)
_ASM_EXTABLE_UA(2b, 16b)
_ASM_EXTABLE_UA(21b, 16b)
_ASM_EXTABLE_UA(3b, 16b)
_ASM_EXTABLE_UA(31b, 16b)
_ASM_EXTABLE_UA(4b, 16b)
_ASM_EXTABLE_UA(41b, 16b)
_ASM_EXTABLE_UA(10b, 16b)
_ASM_EXTABLE_UA(51b, 16b)
_ASM_EXTABLE_UA(11b, 16b)
_ASM_EXTABLE_UA(61b, 16b)
_ASM_EXTABLE_UA(12b, 16b)
_ASM_EXTABLE_UA(71b, 16b)
_ASM_EXTABLE_UA(13b, 16b)
_ASM_EXTABLE_UA(81b, 16b)
_ASM_EXTABLE_UA(14b, 16b)
_ASM_EXTABLE_UA(91b, 16b)
_ASM_EXTABLE_UA(6b, 9b)
_ASM_EXTABLE_UA(7b, 16b)
: "=&c"(size), "=&D" (d0), "=&S" (d1)
: "1"(to), "2"(from), "0"(size)
: "eax", "edx", "memory");
return size;
}
#else
/*
* Leave these declared but undefined. They should not be any references to
* them
*/
unsigned long __copy_user_intel(void __user *to, const void *from,
unsigned long size);
#endif /* CONFIG_X86_INTEL_USERCOPY */
/* Generic arbitrary sized copy. */
#define __copy_user(to, from, size) \
do { \
int __d0, __d1, __d2; \
__asm__ __volatile__( \
" cmp $7,%0\n" \
" jbe 1f\n" \
" movl %1,%0\n" \
" negl %0\n" \
" andl $7,%0\n" \
" subl %0,%3\n" \
"4: rep; movsb\n" \
" movl %3,%0\n" \
" shrl $2,%0\n" \
" andl $3,%3\n" \
" .align 2,0x90\n" \
"0: rep; movsl\n" \
" movl %3,%0\n" \
"1: rep; movsb\n" \
"2:\n" \
".section .fixup,\"ax\"\n" \
"5: addl %3,%0\n" \
" jmp 2b\n" \
"3: lea 0(%3,%0,4),%0\n" \
" jmp 2b\n" \
".previous\n" \
_ASM_EXTABLE_UA(4b, 5b) \
_ASM_EXTABLE_UA(0b, 3b) \
_ASM_EXTABLE_UA(1b, 2b) \
: "=&c"(size), "=&D" (__d0), "=&S" (__d1), "=r"(__d2) \
: "3"(size), "0"(size), "1"(to), "2"(from) \
: "memory"); \
} while (0)
unsigned long __copy_user_ll(void *to, const void *from, unsigned long n)
{
__uaccess_begin_nospec();
if (movsl_is_ok(to, from, n))
__copy_user(to, from, n);
else
n = __copy_user_intel(to, from, n);
__uaccess_end();
return n;
}
EXPORT_SYMBOL(__copy_user_ll);
unsigned long __copy_from_user_ll_nocache_nozero(void *to, const void __user *from,
unsigned long n)
{
__uaccess_begin_nospec();
#ifdef CONFIG_X86_INTEL_USERCOPY
if (n > 64 && static_cpu_has(X86_FEATURE_XMM2))
n = __copy_user_intel_nocache(to, from, n);
else
__copy_user(to, from, n);
#else
__copy_user(to, from, n);
#endif
__uaccess_end();
return n;
}
EXPORT_SYMBOL(__copy_from_user_ll_nocache_nozero);
|
