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1da177e4 LT |
1 | /* |
2 | * linux/arch/m32r/kernel/ptrace.c | |
3 | * | |
4 | * Copyright (C) 2002 Hirokazu Takata, Takeo Takahashi | |
5 | * Copyright (C) 2004 Hirokazu Takata, Kei Sakamoto | |
6 | * | |
7 | * Original x86 implementation: | |
8 | * By Ross Biro 1/23/92 | |
9 | * edited by Linus Torvalds | |
10 | * | |
11 | * Some code taken from sh version: | |
12 | * Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka | |
13 | * Some code taken from arm version: | |
14 | * Copyright (C) 2000 Russell King | |
15 | */ | |
16 | ||
17 | #include <linux/config.h> | |
18 | #include <linux/kernel.h> | |
19 | #include <linux/sched.h> | |
20 | #include <linux/mm.h> | |
21 | #include <linux/smp.h> | |
22 | #include <linux/smp_lock.h> | |
23 | #include <linux/errno.h> | |
24 | #include <linux/ptrace.h> | |
25 | #include <linux/user.h> | |
26 | #include <linux/string.h> | |
7ed20e1a | 27 | #include <linux/signal.h> |
1da177e4 LT |
28 | |
29 | #include <asm/cacheflush.h> | |
30 | #include <asm/io.h> | |
31 | #include <asm/uaccess.h> | |
32 | #include <asm/pgtable.h> | |
33 | #include <asm/system.h> | |
34 | #include <asm/processor.h> | |
35 | #include <asm/mmu_context.h> | |
36 | ||
37 | /* | |
38 | * Get the address of the live pt_regs for the specified task. | |
39 | * These are saved onto the top kernel stack when the process | |
40 | * is not running. | |
41 | * | |
42 | * Note: if a user thread is execve'd from kernel space, the | |
43 | * kernel stack will not be empty on entry to the kernel, so | |
44 | * ptracing these tasks will fail. | |
45 | */ | |
46 | static inline struct pt_regs * | |
47 | get_user_regs(struct task_struct *task) | |
48 | { | |
49 | return (struct pt_regs *) | |
50 | ((unsigned long)task->thread_info + THREAD_SIZE | |
51 | - sizeof(struct pt_regs)); | |
52 | } | |
53 | ||
54 | /* | |
55 | * This routine will get a word off of the process kernel stack. | |
56 | */ | |
57 | static inline unsigned long int | |
58 | get_stack_long(struct task_struct *task, int offset) | |
59 | { | |
60 | unsigned long *stack; | |
61 | ||
62 | stack = (unsigned long *)get_user_regs(task); | |
63 | ||
64 | return stack[offset]; | |
65 | } | |
66 | ||
67 | /* | |
68 | * This routine will put a word on the process kernel stack. | |
69 | */ | |
70 | static inline int | |
71 | put_stack_long(struct task_struct *task, int offset, unsigned long data) | |
72 | { | |
73 | unsigned long *stack; | |
74 | ||
75 | stack = (unsigned long *)get_user_regs(task); | |
76 | stack[offset] = data; | |
77 | ||
78 | return 0; | |
79 | } | |
80 | ||
81 | static int reg_offset[] = { | |
82 | PT_R0, PT_R1, PT_R2, PT_R3, PT_R4, PT_R5, PT_R6, PT_R7, | |
83 | PT_R8, PT_R9, PT_R10, PT_R11, PT_R12, PT_FP, PT_LR, PT_SPU, | |
84 | }; | |
85 | ||
86 | /* | |
87 | * Read the word at offset "off" into the "struct user". We | |
88 | * actually access the pt_regs stored on the kernel stack. | |
89 | */ | |
90 | static int ptrace_read_user(struct task_struct *tsk, unsigned long off, | |
91 | unsigned long __user *data) | |
92 | { | |
93 | unsigned long tmp; | |
94 | #ifndef NO_FPU | |
95 | struct user * dummy = NULL; | |
96 | #endif | |
97 | ||
98 | if ((off & 3) || (off < 0) || (off > sizeof(struct user) - 3)) | |
99 | return -EIO; | |
100 | ||
101 | off >>= 2; | |
102 | switch (off) { | |
103 | case PT_EVB: | |
104 | __asm__ __volatile__ ( | |
105 | "mvfc %0, cr5 \n\t" | |
106 | : "=r" (tmp) | |
107 | ); | |
108 | break; | |
109 | case PT_CBR: { | |
110 | unsigned long psw; | |
111 | psw = get_stack_long(tsk, PT_PSW); | |
112 | tmp = ((psw >> 8) & 1); | |
113 | } | |
114 | break; | |
115 | case PT_PSW: { | |
116 | unsigned long psw, bbpsw; | |
117 | psw = get_stack_long(tsk, PT_PSW); | |
118 | bbpsw = get_stack_long(tsk, PT_BBPSW); | |
119 | tmp = ((psw >> 8) & 0xff) | ((bbpsw & 0xff) << 8); | |
120 | } | |
121 | break; | |
122 | case PT_PC: | |
123 | tmp = get_stack_long(tsk, PT_BPC); | |
124 | break; | |
125 | case PT_BPC: | |
126 | off = PT_BBPC; | |
127 | /* fall through */ | |
128 | default: | |
129 | if (off < (sizeof(struct pt_regs) >> 2)) | |
130 | tmp = get_stack_long(tsk, off); | |
131 | #ifndef NO_FPU | |
132 | else if (off >= (long)(&dummy->fpu >> 2) && | |
133 | off < (long)(&dummy->u_fpvalid >> 2)) { | |
134 | if (!tsk_used_math(tsk)) { | |
135 | if (off == (long)(&dummy->fpu.fpscr >> 2)) | |
136 | tmp = FPSCR_INIT; | |
137 | else | |
138 | tmp = 0; | |
139 | } else | |
140 | tmp = ((long *)(&tsk->thread.fpu >> 2)) | |
141 | [off - (long)&dummy->fpu]; | |
142 | } else if (off == (long)(&dummy->u_fpvalid >> 2)) | |
143 | tmp = !!tsk_used_math(tsk); | |
144 | #endif /* not NO_FPU */ | |
145 | else | |
146 | tmp = 0; | |
147 | } | |
148 | ||
149 | return put_user(tmp, data); | |
150 | } | |
151 | ||
152 | static int ptrace_write_user(struct task_struct *tsk, unsigned long off, | |
153 | unsigned long data) | |
154 | { | |
155 | int ret = -EIO; | |
156 | #ifndef NO_FPU | |
157 | struct user * dummy = NULL; | |
158 | #endif | |
159 | ||
160 | if ((off & 3) || off < 0 || | |
161 | off > sizeof(struct user) - 3) | |
162 | return -EIO; | |
163 | ||
164 | off >>= 2; | |
165 | switch (off) { | |
166 | case PT_EVB: | |
167 | case PT_BPC: | |
168 | case PT_SPI: | |
169 | /* We don't allow to modify evb. */ | |
170 | ret = 0; | |
171 | break; | |
172 | case PT_PSW: | |
173 | case PT_CBR: { | |
174 | /* We allow to modify only cbr in psw */ | |
175 | unsigned long psw; | |
176 | psw = get_stack_long(tsk, PT_PSW); | |
177 | psw = (psw & ~0x100) | ((data & 1) << 8); | |
178 | ret = put_stack_long(tsk, PT_PSW, psw); | |
179 | } | |
180 | break; | |
181 | case PT_PC: | |
182 | off = PT_BPC; | |
183 | data &= ~1; | |
184 | /* fall through */ | |
185 | default: | |
186 | if (off < (sizeof(struct pt_regs) >> 2)) | |
187 | ret = put_stack_long(tsk, off, data); | |
188 | #ifndef NO_FPU | |
189 | else if (off >= (long)(&dummy->fpu >> 2) && | |
190 | off < (long)(&dummy->u_fpvalid >> 2)) { | |
191 | set_stopped_child_used_math(tsk); | |
192 | ((long *)&tsk->thread.fpu) | |
193 | [off - (long)&dummy->fpu] = data; | |
194 | ret = 0; | |
195 | } else if (off == (long)(&dummy->u_fpvalid >> 2)) { | |
196 | conditional_stopped_child_used_math(data, tsk); | |
197 | ret = 0; | |
198 | } | |
199 | #endif /* not NO_FPU */ | |
200 | break; | |
201 | } | |
202 | ||
203 | return ret; | |
204 | } | |
205 | ||
206 | /* | |
207 | * Get all user integer registers. | |
208 | */ | |
209 | static int ptrace_getregs(struct task_struct *tsk, void __user *uregs) | |
210 | { | |
211 | struct pt_regs *regs = get_user_regs(tsk); | |
212 | ||
213 | return copy_to_user(uregs, regs, sizeof(struct pt_regs)) ? -EFAULT : 0; | |
214 | } | |
215 | ||
216 | /* | |
217 | * Set all user integer registers. | |
218 | */ | |
219 | static int ptrace_setregs(struct task_struct *tsk, void __user *uregs) | |
220 | { | |
221 | struct pt_regs newregs; | |
222 | int ret; | |
223 | ||
224 | ret = -EFAULT; | |
225 | if (copy_from_user(&newregs, uregs, sizeof(struct pt_regs)) == 0) { | |
226 | struct pt_regs *regs = get_user_regs(tsk); | |
227 | *regs = newregs; | |
228 | ret = 0; | |
229 | } | |
230 | ||
231 | return ret; | |
232 | } | |
233 | ||
234 | ||
235 | static inline int | |
236 | check_condition_bit(struct task_struct *child) | |
237 | { | |
238 | return (int)((get_stack_long(child, PT_PSW) >> 8) & 1); | |
239 | } | |
240 | ||
241 | static int | |
242 | check_condition_src(unsigned long op, unsigned long regno1, | |
243 | unsigned long regno2, struct task_struct *child) | |
244 | { | |
245 | unsigned long reg1, reg2; | |
246 | ||
247 | reg2 = get_stack_long(child, reg_offset[regno2]); | |
248 | ||
249 | switch (op) { | |
250 | case 0x0: /* BEQ */ | |
251 | reg1 = get_stack_long(child, reg_offset[regno1]); | |
252 | return reg1 == reg2; | |
253 | case 0x1: /* BNE */ | |
254 | reg1 = get_stack_long(child, reg_offset[regno1]); | |
255 | return reg1 != reg2; | |
256 | case 0x8: /* BEQZ */ | |
257 | return reg2 == 0; | |
258 | case 0x9: /* BNEZ */ | |
259 | return reg2 != 0; | |
260 | case 0xa: /* BLTZ */ | |
261 | return (int)reg2 < 0; | |
262 | case 0xb: /* BGEZ */ | |
263 | return (int)reg2 >= 0; | |
264 | case 0xc: /* BLEZ */ | |
265 | return (int)reg2 <= 0; | |
266 | case 0xd: /* BGTZ */ | |
267 | return (int)reg2 > 0; | |
268 | default: | |
269 | /* never reached */ | |
270 | return 0; | |
271 | } | |
272 | } | |
273 | ||
274 | static void | |
275 | compute_next_pc_for_16bit_insn(unsigned long insn, unsigned long pc, | |
276 | unsigned long *next_pc, | |
277 | struct task_struct *child) | |
278 | { | |
279 | unsigned long op, op2, op3; | |
280 | unsigned long disp; | |
281 | unsigned long regno; | |
282 | int parallel = 0; | |
283 | ||
284 | if (insn & 0x00008000) | |
285 | parallel = 1; | |
286 | if (pc & 3) | |
287 | insn &= 0x7fff; /* right slot */ | |
288 | else | |
289 | insn >>= 16; /* left slot */ | |
290 | ||
291 | op = (insn >> 12) & 0xf; | |
292 | op2 = (insn >> 8) & 0xf; | |
293 | op3 = (insn >> 4) & 0xf; | |
294 | ||
295 | if (op == 0x7) { | |
296 | switch (op2) { | |
297 | case 0xd: /* BNC */ | |
298 | case 0x9: /* BNCL */ | |
299 | if (!check_condition_bit(child)) { | |
300 | disp = (long)(insn << 24) >> 22; | |
301 | *next_pc = (pc & ~0x3) + disp; | |
302 | return; | |
303 | } | |
304 | break; | |
305 | case 0x8: /* BCL */ | |
306 | case 0xc: /* BC */ | |
307 | if (check_condition_bit(child)) { | |
308 | disp = (long)(insn << 24) >> 22; | |
309 | *next_pc = (pc & ~0x3) + disp; | |
310 | return; | |
311 | } | |
312 | break; | |
313 | case 0xe: /* BL */ | |
314 | case 0xf: /* BRA */ | |
315 | disp = (long)(insn << 24) >> 22; | |
316 | *next_pc = (pc & ~0x3) + disp; | |
317 | return; | |
318 | break; | |
319 | } | |
320 | } else if (op == 0x1) { | |
321 | switch (op2) { | |
322 | case 0x0: | |
323 | if (op3 == 0xf) { /* TRAP */ | |
324 | #if 1 | |
325 | /* pass through */ | |
326 | #else | |
327 | /* kernel space is not allowed as next_pc */ | |
328 | unsigned long evb; | |
329 | unsigned long trapno; | |
330 | trapno = insn & 0xf; | |
331 | __asm__ __volatile__ ( | |
332 | "mvfc %0, cr5\n" | |
333 | :"=r"(evb) | |
334 | : | |
335 | ); | |
336 | *next_pc = evb + (trapno << 2); | |
337 | return; | |
338 | #endif | |
339 | } else if (op3 == 0xd) { /* RTE */ | |
340 | *next_pc = get_stack_long(child, PT_BPC); | |
341 | return; | |
342 | } | |
343 | break; | |
344 | case 0xc: /* JC */ | |
345 | if (op3 == 0xc && check_condition_bit(child)) { | |
346 | regno = insn & 0xf; | |
347 | *next_pc = get_stack_long(child, | |
348 | reg_offset[regno]); | |
349 | return; | |
350 | } | |
351 | break; | |
352 | case 0xd: /* JNC */ | |
353 | if (op3 == 0xc && !check_condition_bit(child)) { | |
354 | regno = insn & 0xf; | |
355 | *next_pc = get_stack_long(child, | |
356 | reg_offset[regno]); | |
357 | return; | |
358 | } | |
359 | break; | |
360 | case 0xe: /* JL */ | |
361 | case 0xf: /* JMP */ | |
362 | if (op3 == 0xc) { /* JMP */ | |
363 | regno = insn & 0xf; | |
364 | *next_pc = get_stack_long(child, | |
365 | reg_offset[regno]); | |
366 | return; | |
367 | } | |
368 | break; | |
369 | } | |
370 | } | |
371 | if (parallel) | |
372 | *next_pc = pc + 4; | |
373 | else | |
374 | *next_pc = pc + 2; | |
375 | } | |
376 | ||
377 | static void | |
378 | compute_next_pc_for_32bit_insn(unsigned long insn, unsigned long pc, | |
379 | unsigned long *next_pc, | |
380 | struct task_struct *child) | |
381 | { | |
382 | unsigned long op; | |
383 | unsigned long op2; | |
384 | unsigned long disp; | |
385 | unsigned long regno1, regno2; | |
386 | ||
387 | op = (insn >> 28) & 0xf; | |
388 | if (op == 0xf) { /* branch 24-bit relative */ | |
389 | op2 = (insn >> 24) & 0xf; | |
390 | switch (op2) { | |
391 | case 0xd: /* BNC */ | |
392 | case 0x9: /* BNCL */ | |
393 | if (!check_condition_bit(child)) { | |
394 | disp = (long)(insn << 8) >> 6; | |
395 | *next_pc = (pc & ~0x3) + disp; | |
396 | return; | |
397 | } | |
398 | break; | |
399 | case 0x8: /* BCL */ | |
400 | case 0xc: /* BC */ | |
401 | if (check_condition_bit(child)) { | |
402 | disp = (long)(insn << 8) >> 6; | |
403 | *next_pc = (pc & ~0x3) + disp; | |
404 | return; | |
405 | } | |
406 | break; | |
407 | case 0xe: /* BL */ | |
408 | case 0xf: /* BRA */ | |
409 | disp = (long)(insn << 8) >> 6; | |
410 | *next_pc = (pc & ~0x3) + disp; | |
411 | return; | |
412 | } | |
413 | } else if (op == 0xb) { /* branch 16-bit relative */ | |
414 | op2 = (insn >> 20) & 0xf; | |
415 | switch (op2) { | |
416 | case 0x0: /* BEQ */ | |
417 | case 0x1: /* BNE */ | |
418 | case 0x8: /* BEQZ */ | |
419 | case 0x9: /* BNEZ */ | |
420 | case 0xa: /* BLTZ */ | |
421 | case 0xb: /* BGEZ */ | |
422 | case 0xc: /* BLEZ */ | |
423 | case 0xd: /* BGTZ */ | |
424 | regno1 = ((insn >> 24) & 0xf); | |
425 | regno2 = ((insn >> 16) & 0xf); | |
426 | if (check_condition_src(op2, regno1, regno2, child)) { | |
427 | disp = (long)(insn << 16) >> 14; | |
428 | *next_pc = (pc & ~0x3) + disp; | |
429 | return; | |
430 | } | |
431 | break; | |
432 | } | |
433 | } | |
434 | *next_pc = pc + 4; | |
435 | } | |
436 | ||
437 | static inline void | |
438 | compute_next_pc(unsigned long insn, unsigned long pc, | |
439 | unsigned long *next_pc, struct task_struct *child) | |
440 | { | |
441 | if (insn & 0x80000000) | |
442 | compute_next_pc_for_32bit_insn(insn, pc, next_pc, child); | |
443 | else | |
444 | compute_next_pc_for_16bit_insn(insn, pc, next_pc, child); | |
445 | } | |
446 | ||
447 | static int | |
448 | register_debug_trap(struct task_struct *child, unsigned long next_pc, | |
449 | unsigned long next_insn, unsigned long *code) | |
450 | { | |
451 | struct debug_trap *p = &child->thread.debug_trap; | |
452 | unsigned long addr = next_pc & ~3; | |
453 | ||
454 | if (p->nr_trap == MAX_TRAPS) { | |
455 | printk("kernel BUG at %s %d: p->nr_trap = %d\n", | |
456 | __FILE__, __LINE__, p->nr_trap); | |
457 | return -1; | |
458 | } | |
459 | p->addr[p->nr_trap] = addr; | |
460 | p->insn[p->nr_trap] = next_insn; | |
461 | p->nr_trap++; | |
462 | if (next_pc & 3) { | |
463 | *code = (next_insn & 0xffff0000) | 0x10f1; | |
464 | /* xxx --> TRAP1 */ | |
465 | } else { | |
466 | if ((next_insn & 0x80000000) || (next_insn & 0x8000)) { | |
467 | *code = 0x10f17000; | |
468 | /* TRAP1 --> NOP */ | |
469 | } else { | |
470 | *code = (next_insn & 0xffff) | 0x10f10000; | |
471 | /* TRAP1 --> xxx */ | |
472 | } | |
473 | } | |
474 | return 0; | |
475 | } | |
476 | ||
477 | static int | |
478 | unregister_debug_trap(struct task_struct *child, unsigned long addr, | |
479 | unsigned long *code) | |
480 | { | |
481 | struct debug_trap *p = &child->thread.debug_trap; | |
482 | int i; | |
483 | ||
484 | /* Search debug trap entry. */ | |
485 | for (i = 0; i < p->nr_trap; i++) { | |
486 | if (p->addr[i] == addr) | |
487 | break; | |
488 | } | |
489 | if (i >= p->nr_trap) { | |
490 | /* The trap may be requested from debugger. | |
491 | * ptrace should do nothing in this case. | |
492 | */ | |
493 | return 0; | |
494 | } | |
495 | ||
496 | /* Recover orignal instruction code. */ | |
497 | *code = p->insn[i]; | |
498 | ||
499 | /* Shift debug trap entries. */ | |
500 | while (i < p->nr_trap - 1) { | |
501 | p->insn[i] = p->insn[i + 1]; | |
502 | p->addr[i] = p->addr[i + 1]; | |
503 | i++; | |
504 | } | |
505 | p->nr_trap--; | |
506 | return 1; | |
507 | } | |
508 | ||
509 | static void | |
510 | unregister_all_debug_traps(struct task_struct *child) | |
511 | { | |
512 | struct debug_trap *p = &child->thread.debug_trap; | |
513 | int i; | |
514 | ||
515 | for (i = 0; i < p->nr_trap; i++) | |
516 | access_process_vm(child, p->addr[i], &p->insn[i], sizeof(p->insn[i]), 1); | |
517 | p->nr_trap = 0; | |
518 | } | |
519 | ||
520 | static inline void | |
521 | invalidate_cache(void) | |
522 | { | |
523 | #if defined(CONFIG_CHIP_M32700) || defined(CONFIG_CHIP_OPSP) | |
524 | ||
525 | _flush_cache_copyback_all(); | |
526 | ||
527 | #else /* ! CONFIG_CHIP_M32700 */ | |
528 | ||
529 | /* Invalidate cache */ | |
530 | __asm__ __volatile__ ( | |
531 | "ldi r0, #-1 \n\t" | |
532 | "ldi r1, #0 \n\t" | |
533 | "stb r1, @r0 ; cache off \n\t" | |
534 | "; \n\t" | |
535 | "ldi r0, #-2 \n\t" | |
536 | "ldi r1, #1 \n\t" | |
537 | "stb r1, @r0 ; cache invalidate \n\t" | |
538 | ".fillinsn \n" | |
539 | "0: \n\t" | |
540 | "ldb r1, @r0 ; invalidate check \n\t" | |
541 | "bnez r1, 0b \n\t" | |
542 | "; \n\t" | |
543 | "ldi r0, #-1 \n\t" | |
544 | "ldi r1, #1 \n\t" | |
545 | "stb r1, @r0 ; cache on \n\t" | |
546 | : : : "r0", "r1", "memory" | |
547 | ); | |
548 | /* FIXME: copying-back d-cache and invalidating i-cache are needed. | |
549 | */ | |
550 | #endif /* CONFIG_CHIP_M32700 */ | |
551 | } | |
552 | ||
553 | /* Embed a debug trap (TRAP1) code */ | |
554 | static int | |
555 | embed_debug_trap(struct task_struct *child, unsigned long next_pc) | |
556 | { | |
557 | unsigned long next_insn, code; | |
558 | unsigned long addr = next_pc & ~3; | |
559 | ||
560 | if (access_process_vm(child, addr, &next_insn, sizeof(next_insn), 0) | |
561 | != sizeof(next_insn)) { | |
562 | return -1; /* error */ | |
563 | } | |
564 | ||
565 | /* Set a trap code. */ | |
566 | if (register_debug_trap(child, next_pc, next_insn, &code)) { | |
567 | return -1; /* error */ | |
568 | } | |
569 | if (access_process_vm(child, addr, &code, sizeof(code), 1) | |
570 | != sizeof(code)) { | |
571 | return -1; /* error */ | |
572 | } | |
573 | return 0; /* success */ | |
574 | } | |
575 | ||
576 | void | |
577 | withdraw_debug_trap(struct pt_regs *regs) | |
578 | { | |
579 | unsigned long addr; | |
580 | unsigned long code; | |
581 | ||
582 | addr = (regs->bpc - 2) & ~3; | |
583 | regs->bpc -= 2; | |
584 | if (unregister_debug_trap(current, addr, &code)) { | |
585 | access_process_vm(current, addr, &code, sizeof(code), 1); | |
586 | invalidate_cache(); | |
587 | } | |
588 | } | |
589 | ||
590 | static void | |
591 | init_debug_traps(struct task_struct *child) | |
592 | { | |
593 | struct debug_trap *p = &child->thread.debug_trap; | |
594 | int i; | |
595 | p->nr_trap = 0; | |
596 | for (i = 0; i < MAX_TRAPS; i++) { | |
597 | p->addr[i] = 0; | |
598 | p->insn[i] = 0; | |
599 | } | |
600 | } | |
601 | ||
602 | ||
603 | /* | |
604 | * Called by kernel/ptrace.c when detaching.. | |
605 | * | |
606 | * Make sure single step bits etc are not set. | |
607 | */ | |
608 | void ptrace_disable(struct task_struct *child) | |
609 | { | |
610 | /* nothing to do.. */ | |
611 | } | |
612 | ||
613 | static int | |
614 | do_ptrace(long request, struct task_struct *child, long addr, long data) | |
615 | { | |
616 | unsigned long tmp; | |
617 | int ret; | |
618 | ||
619 | switch (request) { | |
620 | /* | |
621 | * read word at location "addr" in the child process. | |
622 | */ | |
623 | case PTRACE_PEEKTEXT: | |
624 | case PTRACE_PEEKDATA: | |
625 | ret = access_process_vm(child, addr, &tmp, sizeof(tmp), 0); | |
626 | if (ret == sizeof(tmp)) | |
627 | ret = put_user(tmp,(unsigned long __user *) data); | |
628 | else | |
629 | ret = -EIO; | |
630 | break; | |
631 | ||
632 | /* | |
633 | * read the word at location addr in the USER area. | |
634 | */ | |
635 | case PTRACE_PEEKUSR: | |
636 | ret = ptrace_read_user(child, addr, | |
637 | (unsigned long __user *)data); | |
638 | break; | |
639 | ||
640 | /* | |
641 | * write the word at location addr. | |
642 | */ | |
643 | case PTRACE_POKETEXT: | |
644 | case PTRACE_POKEDATA: | |
645 | ret = access_process_vm(child, addr, &data, sizeof(data), 1); | |
646 | if (ret == sizeof(data)) { | |
647 | ret = 0; | |
648 | if (request == PTRACE_POKETEXT) { | |
649 | invalidate_cache(); | |
650 | } | |
651 | } else { | |
652 | ret = -EIO; | |
653 | } | |
654 | break; | |
655 | ||
656 | /* | |
657 | * write the word at location addr in the USER area. | |
658 | */ | |
659 | case PTRACE_POKEUSR: | |
660 | ret = ptrace_write_user(child, addr, data); | |
661 | break; | |
662 | ||
663 | /* | |
664 | * continue/restart and stop at next (return from) syscall | |
665 | */ | |
666 | case PTRACE_SYSCALL: | |
667 | case PTRACE_CONT: | |
668 | ret = -EIO; | |
7ed20e1a | 669 | if (!valid_signal(data)) |
1da177e4 LT |
670 | break; |
671 | if (request == PTRACE_SYSCALL) | |
672 | set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); | |
673 | else | |
674 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); | |
675 | child->exit_code = data; | |
676 | wake_up_process(child); | |
677 | ret = 0; | |
678 | break; | |
679 | ||
680 | /* | |
681 | * make the child exit. Best I can do is send it a sigkill. | |
682 | * perhaps it should be put in the status that it wants to | |
683 | * exit. | |
684 | */ | |
685 | case PTRACE_KILL: { | |
686 | ret = 0; | |
687 | unregister_all_debug_traps(child); | |
688 | invalidate_cache(); | |
689 | if (child->exit_state == EXIT_ZOMBIE) /* already dead */ | |
690 | break; | |
691 | child->exit_code = SIGKILL; | |
692 | wake_up_process(child); | |
693 | break; | |
694 | } | |
695 | ||
696 | /* | |
697 | * execute single instruction. | |
698 | */ | |
699 | case PTRACE_SINGLESTEP: { | |
700 | unsigned long next_pc; | |
701 | unsigned long pc, insn; | |
702 | ||
703 | ret = -EIO; | |
7ed20e1a | 704 | if (!valid_signal(data)) |
1da177e4 LT |
705 | break; |
706 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); | |
707 | if ((child->ptrace & PT_DTRACE) == 0) { | |
708 | /* Spurious delayed TF traps may occur */ | |
709 | child->ptrace |= PT_DTRACE; | |
710 | } | |
711 | ||
712 | /* Compute next pc. */ | |
713 | pc = get_stack_long(child, PT_BPC); | |
714 | ||
715 | if (access_process_vm(child, pc&~3, &insn, sizeof(insn), 0) | |
716 | != sizeof(insn)) | |
717 | break; | |
718 | ||
719 | compute_next_pc(insn, pc, &next_pc, child); | |
720 | if (next_pc & 0x80000000) | |
721 | break; | |
722 | ||
723 | if (embed_debug_trap(child, next_pc)) | |
724 | break; | |
725 | ||
726 | invalidate_cache(); | |
727 | child->exit_code = data; | |
728 | ||
729 | /* give it a chance to run. */ | |
730 | wake_up_process(child); | |
731 | ret = 0; | |
732 | break; | |
733 | } | |
734 | ||
735 | /* | |
736 | * detach a process that was attached. | |
737 | */ | |
738 | case PTRACE_DETACH: | |
739 | ret = 0; | |
740 | ret = ptrace_detach(child, data); | |
741 | break; | |
742 | ||
743 | case PTRACE_GETREGS: | |
744 | ret = ptrace_getregs(child, (void __user *)data); | |
745 | break; | |
746 | ||
747 | case PTRACE_SETREGS: | |
748 | ret = ptrace_setregs(child, (void __user *)data); | |
749 | break; | |
750 | ||
751 | default: | |
752 | ret = ptrace_request(child, request, addr, data); | |
753 | break; | |
754 | } | |
755 | ||
756 | return ret; | |
757 | } | |
758 | ||
dfb7dac3 | 759 | asmlinkage long sys_ptrace(long request, long pid, long addr, long data) |
1da177e4 LT |
760 | { |
761 | struct task_struct *child; | |
762 | int ret; | |
763 | ||
764 | lock_kernel(); | |
765 | ret = -EPERM; | |
766 | if (request == PTRACE_TRACEME) { | |
767 | /* are we already being traced? */ | |
768 | if (current->ptrace & PT_PTRACED) | |
769 | goto out; | |
770 | /* set the ptrace bit in the process flags. */ | |
771 | current->ptrace |= PT_PTRACED; | |
772 | ret = 0; | |
773 | goto out; | |
774 | } | |
775 | ret = -ESRCH; | |
776 | read_lock(&tasklist_lock); | |
777 | child = find_task_by_pid(pid); | |
778 | if (child) | |
779 | get_task_struct(child); | |
780 | read_unlock(&tasklist_lock); | |
781 | if (!child) | |
782 | goto out; | |
783 | ||
784 | ret = -EPERM; | |
785 | if (pid == 1) /* you may not mess with init */ | |
786 | goto out; | |
787 | ||
788 | if (request == PTRACE_ATTACH) { | |
789 | ret = ptrace_attach(child); | |
790 | if (ret == 0) | |
791 | init_debug_traps(child); | |
792 | goto out_tsk; | |
793 | } | |
794 | ||
795 | ret = ptrace_check_attach(child, request == PTRACE_KILL); | |
796 | if (ret == 0) | |
797 | ret = do_ptrace(request, child, addr, data); | |
798 | ||
799 | out_tsk: | |
800 | put_task_struct(child); | |
801 | out: | |
802 | unlock_kernel(); | |
803 | ||
804 | return ret; | |
805 | } | |
806 | ||
807 | /* notification of system call entry/exit | |
808 | * - triggered by current->work.syscall_trace | |
809 | */ | |
810 | void do_syscall_trace(void) | |
811 | { | |
812 | if (!test_thread_flag(TIF_SYSCALL_TRACE)) | |
813 | return; | |
814 | if (!(current->ptrace & PT_PTRACED)) | |
815 | return; | |
816 | /* the 0x80 provides a way for the tracing parent to distinguish | |
817 | between a syscall stop and SIGTRAP delivery */ | |
818 | ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) | |
819 | ? 0x80 : 0)); | |
820 | ||
821 | /* | |
822 | * this isn't the same as continuing with a signal, but it will do | |
823 | * for normal use. strace only continues with a signal if the | |
824 | * stopping signal is not SIGTRAP. -brl | |
825 | */ | |
826 | if (current->exit_code) { | |
827 | send_sig(current->exit_code, current, 1); | |
828 | current->exit_code = 0; | |
829 | } | |
830 | } |