1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Fault Injection Test harness (FI)
4 * Copyright (C) Intel Crop.
5 */
6
7 /* Id: pf_in.c,v 1.1.1.1 2002/11/12 05:56:32 brlock Exp
8 * Copyright by Intel Crop., 2002
9 * Louis Zhuang (louis.zhuang@intel.com)
10 *
11 * Bjorn Steinbrink (B.Steinbrink@gmx.de), 2007
12 */
13
14 #include <linux/ptrace.h> /* struct pt_regs */
15 #include "pf_in.h"
16
17 #ifdef __i386__
18 /* IA32 Manual 3, 2-1 */
19 static unsigned char prefix_codes[] = {
20 0xF0, 0xF2, 0xF3, 0x2E, 0x36, 0x3E, 0x26, 0x64,
21 0x65, 0x66, 0x67
22 };
23 /* IA32 Manual 3, 3-432*/
24 static unsigned int reg_rop[] = {
25 0x8A, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F
26 };
27 static unsigned int reg_wop[] = { 0x88, 0x89, 0xAA, 0xAB };
28 static unsigned int imm_wop[] = { 0xC6, 0xC7 };
29 /* IA32 Manual 3, 3-432*/
30 static unsigned int rw8[] = { 0x88, 0x8A, 0xC6, 0xAA };
31 static unsigned int rw32[] = {
32 0x89, 0x8B, 0xC7, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F, 0xAB
33 };
34 static unsigned int mw8[] = { 0x88, 0x8A, 0xC6, 0xB60F, 0xBE0F, 0xAA };
35 static unsigned int mw16[] = { 0xB70F, 0xBF0F };
36 static unsigned int mw32[] = { 0x89, 0x8B, 0xC7, 0xAB };
37 static unsigned int mw64[] = {};
38 #else /* not __i386__ */
39 static unsigned char prefix_codes[] = {
40 0x66, 0x67, 0x2E, 0x3E, 0x26, 0x64, 0x65, 0x36,
41 0xF0, 0xF3, 0xF2,
42 /* REX Prefixes */
43 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
44 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f
45 };
46 /* AMD64 Manual 3, Appendix A*/
47 static unsigned int reg_rop[] = {
48 0x8A, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F
49 };
50 static unsigned int reg_wop[] = { 0x88, 0x89, 0xAA, 0xAB };
51 static unsigned int imm_wop[] = { 0xC6, 0xC7 };
52 static unsigned int rw8[] = { 0xC6, 0x88, 0x8A, 0xAA };
53 static unsigned int rw32[] = {
54 0xC7, 0x89, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F, 0xAB
55 };
56 /* 8 bit only */
57 static unsigned int mw8[] = { 0xC6, 0x88, 0x8A, 0xB60F, 0xBE0F, 0xAA };
58 /* 16 bit only */
59 static unsigned int mw16[] = { 0xB70F, 0xBF0F };
60 /* 16 or 32 bit */
61 static unsigned int mw32[] = { 0xC7 };
62 /* 16, 32 or 64 bit */
63 static unsigned int mw64[] = { 0x89, 0x8B, 0xAB };
64 #endif /* not __i386__ */
65
66 struct prefix_bits {
67 unsigned shorted:1;
68 unsigned enlarged:1;
69 unsigned rexr:1;
70 unsigned rex:1;
71 };
72
skip_prefix(unsigned char * addr,struct prefix_bits * prf)73 static int skip_prefix(unsigned char *addr, struct prefix_bits *prf)
74 {
75 int i;
76 unsigned char *p = addr;
77 prf->shorted = 0;
78 prf->enlarged = 0;
79 prf->rexr = 0;
80 prf->rex = 0;
81
82 restart:
83 for (i = 0; i < ARRAY_SIZE(prefix_codes); i++) {
84 if (*p == prefix_codes[i]) {
85 if (*p == 0x66)
86 prf->shorted = 1;
87 #ifdef __amd64__
88 if ((*p & 0xf8) == 0x48)
89 prf->enlarged = 1;
90 if ((*p & 0xf4) == 0x44)
91 prf->rexr = 1;
92 if ((*p & 0xf0) == 0x40)
93 prf->rex = 1;
94 #endif
95 p++;
96 goto restart;
97 }
98 }
99
100 return (p - addr);
101 }
102
get_opcode(unsigned char * addr,unsigned int * opcode)103 static int get_opcode(unsigned char *addr, unsigned int *opcode)
104 {
105 int len;
106
107 if (*addr == 0x0F) {
108 /* 0x0F is extension instruction */
109 *opcode = *(unsigned short *)addr;
110 len = 2;
111 } else {
112 *opcode = *addr;
113 len = 1;
114 }
115
116 return len;
117 }
118
119 #define CHECK_OP_TYPE(opcode, array, type) \
120 for (i = 0; i < ARRAY_SIZE(array); i++) { \
121 if (array[i] == opcode) { \
122 rv = type; \
123 goto exit; \
124 } \
125 }
126
get_ins_type(unsigned long ins_addr)127 enum reason_type get_ins_type(unsigned long ins_addr)
128 {
129 unsigned int opcode;
130 unsigned char *p;
131 struct prefix_bits prf;
132 int i;
133 enum reason_type rv = OTHERS;
134
135 p = (unsigned char *)ins_addr;
136 p += skip_prefix(p, &prf);
137 p += get_opcode(p, &opcode);
138
139 CHECK_OP_TYPE(opcode, reg_rop, REG_READ);
140 CHECK_OP_TYPE(opcode, reg_wop, REG_WRITE);
141 CHECK_OP_TYPE(opcode, imm_wop, IMM_WRITE);
142
143 exit:
144 return rv;
145 }
146 #undef CHECK_OP_TYPE
147
get_ins_reg_width(unsigned long ins_addr)148 static unsigned int get_ins_reg_width(unsigned long ins_addr)
149 {
150 unsigned int opcode;
151 unsigned char *p;
152 struct prefix_bits prf;
153 int i;
154
155 p = (unsigned char *)ins_addr;
156 p += skip_prefix(p, &prf);
157 p += get_opcode(p, &opcode);
158
159 for (i = 0; i < ARRAY_SIZE(rw8); i++)
160 if (rw8[i] == opcode)
161 return 1;
162
163 for (i = 0; i < ARRAY_SIZE(rw32); i++)
164 if (rw32[i] == opcode)
165 return prf.shorted ? 2 : (prf.enlarged ? 8 : 4);
166
167 printk(KERN_ERR "mmiotrace: Unknown opcode 0x%02x\n", opcode);
168 return 0;
169 }
170
get_ins_mem_width(unsigned long ins_addr)171 unsigned int get_ins_mem_width(unsigned long ins_addr)
172 {
173 unsigned int opcode;
174 unsigned char *p;
175 struct prefix_bits prf;
176 int i;
177
178 p = (unsigned char *)ins_addr;
179 p += skip_prefix(p, &prf);
180 p += get_opcode(p, &opcode);
181
182 for (i = 0; i < ARRAY_SIZE(mw8); i++)
183 if (mw8[i] == opcode)
184 return 1;
185
186 for (i = 0; i < ARRAY_SIZE(mw16); i++)
187 if (mw16[i] == opcode)
188 return 2;
189
190 for (i = 0; i < ARRAY_SIZE(mw32); i++)
191 if (mw32[i] == opcode)
192 return prf.shorted ? 2 : 4;
193
194 for (i = 0; i < ARRAY_SIZE(mw64); i++)
195 if (mw64[i] == opcode)
196 return prf.shorted ? 2 : (prf.enlarged ? 8 : 4);
197
198 printk(KERN_ERR "mmiotrace: Unknown opcode 0x%02x\n", opcode);
199 return 0;
200 }
201
202 /*
203 * Define register ident in mod/rm byte.
204 * Note: these are NOT the same as in ptrace-abi.h.
205 */
206 enum {
207 arg_AL = 0,
208 arg_CL = 1,
209 arg_DL = 2,
210 arg_BL = 3,
211 arg_AH = 4,
212 arg_CH = 5,
213 arg_DH = 6,
214 arg_BH = 7,
215
216 arg_AX = 0,
217 arg_CX = 1,
218 arg_DX = 2,
219 arg_BX = 3,
220 arg_SP = 4,
221 arg_BP = 5,
222 arg_SI = 6,
223 arg_DI = 7,
224 #ifdef __amd64__
225 arg_R8 = 8,
226 arg_R9 = 9,
227 arg_R10 = 10,
228 arg_R11 = 11,
229 arg_R12 = 12,
230 arg_R13 = 13,
231 arg_R14 = 14,
232 arg_R15 = 15
233 #endif
234 };
235
get_reg_w8(int no,int rex,struct pt_regs * regs)236 static unsigned char *get_reg_w8(int no, int rex, struct pt_regs *regs)
237 {
238 unsigned char *rv = NULL;
239
240 switch (no) {
241 case arg_AL:
242 rv = (unsigned char *)®s->ax;
243 break;
244 case arg_BL:
245 rv = (unsigned char *)®s->bx;
246 break;
247 case arg_CL:
248 rv = (unsigned char *)®s->cx;
249 break;
250 case arg_DL:
251 rv = (unsigned char *)®s->dx;
252 break;
253 #ifdef __amd64__
254 case arg_R8:
255 rv = (unsigned char *)®s->r8;
256 break;
257 case arg_R9:
258 rv = (unsigned char *)®s->r9;
259 break;
260 case arg_R10:
261 rv = (unsigned char *)®s->r10;
262 break;
263 case arg_R11:
264 rv = (unsigned char *)®s->r11;
265 break;
266 case arg_R12:
267 rv = (unsigned char *)®s->r12;
268 break;
269 case arg_R13:
270 rv = (unsigned char *)®s->r13;
271 break;
272 case arg_R14:
273 rv = (unsigned char *)®s->r14;
274 break;
275 case arg_R15:
276 rv = (unsigned char *)®s->r15;
277 break;
278 #endif
279 default:
280 break;
281 }
282
283 if (rv)
284 return rv;
285
286 if (rex) {
287 /*
288 * If REX prefix exists, access low bytes of SI etc.
289 * instead of AH etc.
290 */
291 switch (no) {
292 case arg_SI:
293 rv = (unsigned char *)®s->si;
294 break;
295 case arg_DI:
296 rv = (unsigned char *)®s->di;
297 break;
298 case arg_BP:
299 rv = (unsigned char *)®s->bp;
300 break;
301 case arg_SP:
302 rv = (unsigned char *)®s->sp;
303 break;
304 default:
305 break;
306 }
307 } else {
308 switch (no) {
309 case arg_AH:
310 rv = 1 + (unsigned char *)®s->ax;
311 break;
312 case arg_BH:
313 rv = 1 + (unsigned char *)®s->bx;
314 break;
315 case arg_CH:
316 rv = 1 + (unsigned char *)®s->cx;
317 break;
318 case arg_DH:
319 rv = 1 + (unsigned char *)®s->dx;
320 break;
321 default:
322 break;
323 }
324 }
325
326 if (!rv)
327 printk(KERN_ERR "mmiotrace: Error reg no# %d\n", no);
328
329 return rv;
330 }
331
get_reg_w32(int no,struct pt_regs * regs)332 static unsigned long *get_reg_w32(int no, struct pt_regs *regs)
333 {
334 unsigned long *rv = NULL;
335
336 switch (no) {
337 case arg_AX:
338 rv = ®s->ax;
339 break;
340 case arg_BX:
341 rv = ®s->bx;
342 break;
343 case arg_CX:
344 rv = ®s->cx;
345 break;
346 case arg_DX:
347 rv = ®s->dx;
348 break;
349 case arg_SP:
350 rv = ®s->sp;
351 break;
352 case arg_BP:
353 rv = ®s->bp;
354 break;
355 case arg_SI:
356 rv = ®s->si;
357 break;
358 case arg_DI:
359 rv = ®s->di;
360 break;
361 #ifdef __amd64__
362 case arg_R8:
363 rv = ®s->r8;
364 break;
365 case arg_R9:
366 rv = ®s->r9;
367 break;
368 case arg_R10:
369 rv = ®s->r10;
370 break;
371 case arg_R11:
372 rv = ®s->r11;
373 break;
374 case arg_R12:
375 rv = ®s->r12;
376 break;
377 case arg_R13:
378 rv = ®s->r13;
379 break;
380 case arg_R14:
381 rv = ®s->r14;
382 break;
383 case arg_R15:
384 rv = ®s->r15;
385 break;
386 #endif
387 default:
388 printk(KERN_ERR "mmiotrace: Error reg no# %d\n", no);
389 }
390
391 return rv;
392 }
393
get_ins_reg_val(unsigned long ins_addr,struct pt_regs * regs)394 unsigned long get_ins_reg_val(unsigned long ins_addr, struct pt_regs *regs)
395 {
396 unsigned int opcode;
397 int reg;
398 unsigned char *p;
399 struct prefix_bits prf;
400 int i;
401
402 p = (unsigned char *)ins_addr;
403 p += skip_prefix(p, &prf);
404 p += get_opcode(p, &opcode);
405 for (i = 0; i < ARRAY_SIZE(reg_rop); i++)
406 if (reg_rop[i] == opcode)
407 goto do_work;
408
409 for (i = 0; i < ARRAY_SIZE(reg_wop); i++)
410 if (reg_wop[i] == opcode)
411 goto do_work;
412
413 printk(KERN_ERR "mmiotrace: Not a register instruction, opcode "
414 "0x%02x\n", opcode);
415 goto err;
416
417 do_work:
418 /* for STOS, source register is fixed */
419 if (opcode == 0xAA || opcode == 0xAB) {
420 reg = arg_AX;
421 } else {
422 unsigned char mod_rm = *p;
423 reg = ((mod_rm >> 3) & 0x7) | (prf.rexr << 3);
424 }
425 switch (get_ins_reg_width(ins_addr)) {
426 case 1:
427 return *get_reg_w8(reg, prf.rex, regs);
428
429 case 2:
430 return *(unsigned short *)get_reg_w32(reg, regs);
431
432 case 4:
433 return *(unsigned int *)get_reg_w32(reg, regs);
434
435 #ifdef __amd64__
436 case 8:
437 return *(unsigned long *)get_reg_w32(reg, regs);
438 #endif
439
440 default:
441 printk(KERN_ERR "mmiotrace: Error width# %d\n", reg);
442 }
443
444 err:
445 return 0;
446 }
447
get_ins_imm_val(unsigned long ins_addr)448 unsigned long get_ins_imm_val(unsigned long ins_addr)
449 {
450 unsigned int opcode;
451 unsigned char mod_rm;
452 unsigned char mod;
453 unsigned char *p;
454 struct prefix_bits prf;
455 int i;
456
457 p = (unsigned char *)ins_addr;
458 p += skip_prefix(p, &prf);
459 p += get_opcode(p, &opcode);
460 for (i = 0; i < ARRAY_SIZE(imm_wop); i++)
461 if (imm_wop[i] == opcode)
462 goto do_work;
463
464 printk(KERN_ERR "mmiotrace: Not an immediate instruction, opcode "
465 "0x%02x\n", opcode);
466 goto err;
467
468 do_work:
469 mod_rm = *p;
470 mod = mod_rm >> 6;
471 p++;
472 switch (mod) {
473 case 0:
474 /* if r/m is 5 we have a 32 disp (IA32 Manual 3, Table 2-2) */
475 /* AMD64: XXX Check for address size prefix? */
476 if ((mod_rm & 0x7) == 0x5)
477 p += 4;
478 break;
479
480 case 1:
481 p += 1;
482 break;
483
484 case 2:
485 p += 4;
486 break;
487
488 case 3:
489 default:
490 printk(KERN_ERR "mmiotrace: not a memory access instruction "
491 "at 0x%lx, rm_mod=0x%02x\n",
492 ins_addr, mod_rm);
493 }
494
495 switch (get_ins_reg_width(ins_addr)) {
496 case 1:
497 return *(unsigned char *)p;
498
499 case 2:
500 return *(unsigned short *)p;
501
502 case 4:
503 return *(unsigned int *)p;
504
505 #ifdef __amd64__
506 case 8:
507 return *(unsigned long *)p;
508 #endif
509
510 default:
511 printk(KERN_ERR "mmiotrace: Error: width.\n");
512 }
513
514 err:
515 return 0;
516 }
517
