Commit | Line | Data |
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1da177e4 LT |
1 | /* ptrace.c */ |
2 | /* By Ross Biro 1/23/92 */ | |
3 | /* | |
4 | * Pentium III FXSR, SSE support | |
5 | * Gareth Hughes <gareth@valinux.com>, May 2000 | |
6 | */ | |
7 | ||
8 | #include <linux/kernel.h> | |
9 | #include <linux/sched.h> | |
10 | #include <linux/mm.h> | |
11 | #include <linux/smp.h> | |
1da177e4 LT |
12 | #include <linux/errno.h> |
13 | #include <linux/ptrace.h> | |
14 | #include <linux/user.h> | |
15 | #include <linux/security.h> | |
16 | #include <linux/audit.h> | |
17 | #include <linux/seccomp.h> | |
7ed20e1a | 18 | #include <linux/signal.h> |
1da177e4 LT |
19 | |
20 | #include <asm/uaccess.h> | |
21 | #include <asm/pgtable.h> | |
22 | #include <asm/system.h> | |
23 | #include <asm/processor.h> | |
24 | #include <asm/i387.h> | |
25 | #include <asm/debugreg.h> | |
26 | #include <asm/ldt.h> | |
27 | #include <asm/desc.h> | |
28 | ||
29 | /* | |
30 | * does not yet catch signals sent when the child dies. | |
31 | * in exit.c or in signal.c. | |
32 | */ | |
33 | ||
9f155b98 CE |
34 | /* |
35 | * Determines which flags the user has access to [1 = access, 0 = no access]. | |
3c36c6aa | 36 | * Prohibits changing ID(21), VIP(20), VIF(19), VM(17), NT(14), IOPL(12-13), IF(9). |
9f155b98 CE |
37 | * Also masks reserved bits (31-22, 15, 5, 3, 1). |
38 | */ | |
3c36c6aa | 39 | #define FLAG_MASK 0x00050dd5 |
1da177e4 LT |
40 | |
41 | /* set's the trap flag. */ | |
42 | #define TRAP_FLAG 0x100 | |
43 | ||
44 | /* | |
45 | * Offset of eflags on child stack.. | |
46 | */ | |
8701ea95 | 47 | #define EFL_OFFSET offsetof(struct pt_regs, eflags) |
1da177e4 LT |
48 | |
49 | static inline struct pt_regs *get_child_regs(struct task_struct *task) | |
50 | { | |
51 | void *stack_top = (void *)task->thread.esp0; | |
52 | return stack_top - sizeof(struct pt_regs); | |
53 | } | |
54 | ||
55 | /* | |
8701ea95 JF |
56 | * This routine will get a word off of the processes privileged stack. |
57 | * the offset is bytes into the pt_regs structure on the stack. | |
58 | * This routine assumes that all the privileged stacks are in our | |
1da177e4 LT |
59 | * data space. |
60 | */ | |
61 | static inline int get_stack_long(struct task_struct *task, int offset) | |
62 | { | |
63 | unsigned char *stack; | |
64 | ||
8701ea95 | 65 | stack = (unsigned char *)task->thread.esp0 - sizeof(struct pt_regs); |
1da177e4 LT |
66 | stack += offset; |
67 | return (*((int *)stack)); | |
68 | } | |
69 | ||
70 | /* | |
8701ea95 JF |
71 | * This routine will put a word on the processes privileged stack. |
72 | * the offset is bytes into the pt_regs structure on the stack. | |
73 | * This routine assumes that all the privileged stacks are in our | |
1da177e4 LT |
74 | * data space. |
75 | */ | |
76 | static inline int put_stack_long(struct task_struct *task, int offset, | |
77 | unsigned long data) | |
78 | { | |
79 | unsigned char * stack; | |
80 | ||
8701ea95 | 81 | stack = (unsigned char *)task->thread.esp0 - sizeof(struct pt_regs); |
1da177e4 LT |
82 | stack += offset; |
83 | *(unsigned long *) stack = data; | |
84 | return 0; | |
85 | } | |
86 | ||
87 | static int putreg(struct task_struct *child, | |
88 | unsigned long regno, unsigned long value) | |
89 | { | |
90 | switch (regno >> 2) { | |
464d1a78 | 91 | case GS: |
1da177e4 LT |
92 | if (value && (value & 3) != 3) |
93 | return -EIO; | |
464d1a78 | 94 | child->thread.gs = value; |
1da177e4 | 95 | return 0; |
1da177e4 LT |
96 | case DS: |
97 | case ES: | |
464d1a78 | 98 | case FS: |
1da177e4 LT |
99 | if (value && (value & 3) != 3) |
100 | return -EIO; | |
101 | value &= 0xffff; | |
102 | break; | |
103 | case SS: | |
104 | case CS: | |
105 | if ((value & 3) != 3) | |
106 | return -EIO; | |
107 | value &= 0xffff; | |
108 | break; | |
109 | case EFL: | |
110 | value &= FLAG_MASK; | |
111 | value |= get_stack_long(child, EFL_OFFSET) & ~FLAG_MASK; | |
112 | break; | |
113 | } | |
464d1a78 | 114 | if (regno > FS*4) |
66e10a44 | 115 | regno -= 1*4; |
8701ea95 | 116 | put_stack_long(child, regno, value); |
1da177e4 LT |
117 | return 0; |
118 | } | |
119 | ||
120 | static unsigned long getreg(struct task_struct *child, | |
121 | unsigned long regno) | |
122 | { | |
123 | unsigned long retval = ~0UL; | |
124 | ||
125 | switch (regno >> 2) { | |
464d1a78 JF |
126 | case GS: |
127 | retval = child->thread.gs; | |
1da177e4 | 128 | break; |
1da177e4 LT |
129 | case DS: |
130 | case ES: | |
464d1a78 | 131 | case FS: |
1da177e4 LT |
132 | case SS: |
133 | case CS: | |
134 | retval = 0xffff; | |
135 | /* fall through */ | |
136 | default: | |
464d1a78 | 137 | if (regno > FS*4) |
66e10a44 | 138 | regno -= 1*4; |
1da177e4 LT |
139 | retval &= get_stack_long(child, regno); |
140 | } | |
141 | return retval; | |
142 | } | |
143 | ||
144 | #define LDT_SEGMENT 4 | |
145 | ||
146 | static unsigned long convert_eip_to_linear(struct task_struct *child, struct pt_regs *regs) | |
147 | { | |
148 | unsigned long addr, seg; | |
149 | ||
150 | addr = regs->eip; | |
151 | seg = regs->xcs & 0xffff; | |
152 | if (regs->eflags & VM_MASK) { | |
153 | addr = (addr & 0xffff) + (seg << 4); | |
154 | return addr; | |
155 | } | |
156 | ||
157 | /* | |
158 | * We'll assume that the code segments in the GDT | |
159 | * are all zero-based. That is largely true: the | |
160 | * TLS segments are used for data, and the PNPBIOS | |
161 | * and APM bios ones we just ignore here. | |
162 | */ | |
163 | if (seg & LDT_SEGMENT) { | |
164 | u32 *desc; | |
165 | unsigned long base; | |
166 | ||
29eb5110 | 167 | seg &= ~7UL; |
1da177e4 | 168 | |
29eb5110 RM |
169 | down(&child->mm->context.sem); |
170 | if (unlikely((seg >> 3) >= child->mm->context.size)) | |
171 | addr = -1L; /* bogus selector, access would fault */ | |
172 | else { | |
173 | desc = child->mm->context.ldt + seg; | |
174 | base = ((desc[0] >> 16) | | |
175 | ((desc[1] & 0xff) << 16) | | |
176 | (desc[1] & 0xff000000)); | |
177 | ||
178 | /* 16-bit code segment? */ | |
179 | if (!((desc[1] >> 22) & 1)) | |
180 | addr &= 0xffff; | |
181 | addr += base; | |
182 | } | |
1da177e4 LT |
183 | up(&child->mm->context.sem); |
184 | } | |
185 | return addr; | |
186 | } | |
187 | ||
2ade2920 | 188 | static inline int is_setting_trap_flag(struct task_struct *child, struct pt_regs *regs) |
1da177e4 LT |
189 | { |
190 | int i, copied; | |
2ade2920 | 191 | unsigned char opcode[15]; |
1da177e4 LT |
192 | unsigned long addr = convert_eip_to_linear(child, regs); |
193 | ||
194 | copied = access_process_vm(child, addr, opcode, sizeof(opcode), 0); | |
195 | for (i = 0; i < copied; i++) { | |
196 | switch (opcode[i]) { | |
2ade2920 CE |
197 | /* popf and iret */ |
198 | case 0x9d: case 0xcf: | |
1da177e4 LT |
199 | return 1; |
200 | /* opcode and address size prefixes */ | |
201 | case 0x66: case 0x67: | |
202 | continue; | |
203 | /* irrelevant prefixes (segment overrides and repeats) */ | |
204 | case 0x26: case 0x2e: | |
205 | case 0x36: case 0x3e: | |
206 | case 0x64: case 0x65: | |
207 | case 0xf0: case 0xf2: case 0xf3: | |
208 | continue; | |
209 | ||
210 | /* | |
211 | * pushf: NOTE! We should probably not let | |
212 | * the user see the TF bit being set. But | |
213 | * it's more pain than it's worth to avoid | |
214 | * it, and a debugger could emulate this | |
215 | * all in user space if it _really_ cares. | |
216 | */ | |
217 | case 0x9c: | |
218 | default: | |
219 | return 0; | |
220 | } | |
221 | } | |
222 | return 0; | |
223 | } | |
224 | ||
225 | static void set_singlestep(struct task_struct *child) | |
226 | { | |
227 | struct pt_regs *regs = get_child_regs(child); | |
228 | ||
229 | /* | |
230 | * Always set TIF_SINGLESTEP - this guarantees that | |
231 | * we single-step system calls etc.. This will also | |
232 | * cause us to set TF when returning to user mode. | |
233 | */ | |
234 | set_tsk_thread_flag(child, TIF_SINGLESTEP); | |
235 | ||
236 | /* | |
237 | * If TF was already set, don't do anything else | |
238 | */ | |
239 | if (regs->eflags & TRAP_FLAG) | |
240 | return; | |
241 | ||
242 | /* Set TF on the kernel stack.. */ | |
243 | regs->eflags |= TRAP_FLAG; | |
244 | ||
245 | /* | |
246 | * ..but if TF is changed by the instruction we will trace, | |
247 | * don't mark it as being "us" that set it, so that we | |
248 | * won't clear it by hand later. | |
249 | */ | |
2ade2920 | 250 | if (is_setting_trap_flag(child, regs)) |
1da177e4 LT |
251 | return; |
252 | ||
253 | child->ptrace |= PT_DTRACE; | |
254 | } | |
255 | ||
256 | static void clear_singlestep(struct task_struct *child) | |
257 | { | |
258 | /* Always clear TIF_SINGLESTEP... */ | |
259 | clear_tsk_thread_flag(child, TIF_SINGLESTEP); | |
260 | ||
261 | /* But touch TF only if it was set by us.. */ | |
262 | if (child->ptrace & PT_DTRACE) { | |
263 | struct pt_regs *regs = get_child_regs(child); | |
264 | regs->eflags &= ~TRAP_FLAG; | |
265 | child->ptrace &= ~PT_DTRACE; | |
266 | } | |
267 | } | |
268 | ||
269 | /* | |
270 | * Called by kernel/ptrace.c when detaching.. | |
271 | * | |
272 | * Make sure the single step bit is not set. | |
273 | */ | |
274 | void ptrace_disable(struct task_struct *child) | |
275 | { | |
276 | clear_singlestep(child); | |
ab1c23c2 | 277 | clear_tsk_thread_flag(child, TIF_SYSCALL_EMU); |
1da177e4 LT |
278 | } |
279 | ||
280 | /* | |
281 | * Perform get_thread_area on behalf of the traced child. | |
282 | */ | |
283 | static int | |
284 | ptrace_get_thread_area(struct task_struct *child, | |
285 | int idx, struct user_desc __user *user_desc) | |
286 | { | |
287 | struct user_desc info; | |
288 | struct desc_struct *desc; | |
289 | ||
290 | /* | |
291 | * Get the current Thread-Local Storage area: | |
292 | */ | |
293 | ||
294 | #define GET_BASE(desc) ( \ | |
295 | (((desc)->a >> 16) & 0x0000ffff) | \ | |
296 | (((desc)->b << 16) & 0x00ff0000) | \ | |
297 | ( (desc)->b & 0xff000000) ) | |
298 | ||
299 | #define GET_LIMIT(desc) ( \ | |
300 | ((desc)->a & 0x0ffff) | \ | |
301 | ((desc)->b & 0xf0000) ) | |
302 | ||
303 | #define GET_32BIT(desc) (((desc)->b >> 22) & 1) | |
304 | #define GET_CONTENTS(desc) (((desc)->b >> 10) & 3) | |
305 | #define GET_WRITABLE(desc) (((desc)->b >> 9) & 1) | |
306 | #define GET_LIMIT_PAGES(desc) (((desc)->b >> 23) & 1) | |
307 | #define GET_PRESENT(desc) (((desc)->b >> 15) & 1) | |
308 | #define GET_USEABLE(desc) (((desc)->b >> 20) & 1) | |
309 | ||
310 | if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX) | |
311 | return -EINVAL; | |
312 | ||
313 | desc = child->thread.tls_array + idx - GDT_ENTRY_TLS_MIN; | |
314 | ||
315 | info.entry_number = idx; | |
316 | info.base_addr = GET_BASE(desc); | |
317 | info.limit = GET_LIMIT(desc); | |
318 | info.seg_32bit = GET_32BIT(desc); | |
319 | info.contents = GET_CONTENTS(desc); | |
320 | info.read_exec_only = !GET_WRITABLE(desc); | |
321 | info.limit_in_pages = GET_LIMIT_PAGES(desc); | |
322 | info.seg_not_present = !GET_PRESENT(desc); | |
323 | info.useable = GET_USEABLE(desc); | |
324 | ||
325 | if (copy_to_user(user_desc, &info, sizeof(info))) | |
326 | return -EFAULT; | |
327 | ||
328 | return 0; | |
329 | } | |
330 | ||
331 | /* | |
332 | * Perform set_thread_area on behalf of the traced child. | |
333 | */ | |
334 | static int | |
335 | ptrace_set_thread_area(struct task_struct *child, | |
336 | int idx, struct user_desc __user *user_desc) | |
337 | { | |
338 | struct user_desc info; | |
339 | struct desc_struct *desc; | |
340 | ||
341 | if (copy_from_user(&info, user_desc, sizeof(info))) | |
342 | return -EFAULT; | |
343 | ||
344 | if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX) | |
345 | return -EINVAL; | |
346 | ||
347 | desc = child->thread.tls_array + idx - GDT_ENTRY_TLS_MIN; | |
348 | if (LDT_empty(&info)) { | |
349 | desc->a = 0; | |
350 | desc->b = 0; | |
351 | } else { | |
352 | desc->a = LDT_entry_a(&info); | |
353 | desc->b = LDT_entry_b(&info); | |
354 | } | |
355 | ||
356 | return 0; | |
357 | } | |
358 | ||
481bed45 | 359 | long arch_ptrace(struct task_struct *child, long request, long addr, long data) |
1da177e4 | 360 | { |
1da177e4 LT |
361 | struct user * dummy = NULL; |
362 | int i, ret; | |
363 | unsigned long __user *datap = (unsigned long __user *)data; | |
364 | ||
1da177e4 LT |
365 | switch (request) { |
366 | /* when I and D space are separate, these will need to be fixed. */ | |
367 | case PTRACE_PEEKTEXT: /* read word at location addr. */ | |
76647323 AD |
368 | case PTRACE_PEEKDATA: |
369 | ret = generic_ptrace_peekdata(child, addr, data); | |
1da177e4 | 370 | break; |
1da177e4 LT |
371 | |
372 | /* read the word at location addr in the USER area. */ | |
373 | case PTRACE_PEEKUSR: { | |
374 | unsigned long tmp; | |
375 | ||
376 | ret = -EIO; | |
377 | if ((addr & 3) || addr < 0 || | |
378 | addr > sizeof(struct user) - 3) | |
379 | break; | |
380 | ||
381 | tmp = 0; /* Default return condition */ | |
382 | if(addr < FRAME_SIZE*sizeof(long)) | |
383 | tmp = getreg(child, addr); | |
384 | if(addr >= (long) &dummy->u_debugreg[0] && | |
385 | addr <= (long) &dummy->u_debugreg[7]){ | |
386 | addr -= (long) &dummy->u_debugreg[0]; | |
387 | addr = addr >> 2; | |
388 | tmp = child->thread.debugreg[addr]; | |
389 | } | |
390 | ret = put_user(tmp, datap); | |
391 | break; | |
392 | } | |
393 | ||
394 | /* when I and D space are separate, this will have to be fixed. */ | |
395 | case PTRACE_POKETEXT: /* write the word at location addr. */ | |
396 | case PTRACE_POKEDATA: | |
f284ce72 | 397 | ret = generic_ptrace_pokedata(child, addr, data); |
1da177e4 LT |
398 | break; |
399 | ||
400 | case PTRACE_POKEUSR: /* write the word at location addr in the USER area */ | |
401 | ret = -EIO; | |
402 | if ((addr & 3) || addr < 0 || | |
403 | addr > sizeof(struct user) - 3) | |
404 | break; | |
405 | ||
406 | if (addr < FRAME_SIZE*sizeof(long)) { | |
407 | ret = putreg(child, addr, data); | |
408 | break; | |
409 | } | |
410 | /* We need to be very careful here. We implicitly | |
411 | want to modify a portion of the task_struct, and we | |
412 | have to be selective about what portions we allow someone | |
413 | to modify. */ | |
414 | ||
415 | ret = -EIO; | |
416 | if(addr >= (long) &dummy->u_debugreg[0] && | |
417 | addr <= (long) &dummy->u_debugreg[7]){ | |
418 | ||
419 | if(addr == (long) &dummy->u_debugreg[4]) break; | |
420 | if(addr == (long) &dummy->u_debugreg[5]) break; | |
421 | if(addr < (long) &dummy->u_debugreg[4] && | |
422 | ((unsigned long) data) >= TASK_SIZE-3) break; | |
423 | ||
424 | /* Sanity-check data. Take one half-byte at once with | |
425 | * check = (val >> (16 + 4*i)) & 0xf. It contains the | |
426 | * R/Wi and LENi bits; bits 0 and 1 are R/Wi, and bits | |
427 | * 2 and 3 are LENi. Given a list of invalid values, | |
428 | * we do mask |= 1 << invalid_value, so that | |
429 | * (mask >> check) & 1 is a correct test for invalid | |
430 | * values. | |
431 | * | |
432 | * R/Wi contains the type of the breakpoint / | |
433 | * watchpoint, LENi contains the length of the watched | |
434 | * data in the watchpoint case. | |
435 | * | |
436 | * The invalid values are: | |
437 | * - LENi == 0x10 (undefined), so mask |= 0x0f00. | |
438 | * - R/Wi == 0x10 (break on I/O reads or writes), so | |
439 | * mask |= 0x4444. | |
440 | * - R/Wi == 0x00 && LENi != 0x00, so we have mask |= | |
441 | * 0x1110. | |
442 | * | |
443 | * Finally, mask = 0x0f00 | 0x4444 | 0x1110 == 0x5f54. | |
444 | * | |
445 | * See the Intel Manual "System Programming Guide", | |
446 | * 15.2.4 | |
447 | * | |
448 | * Note that LENi == 0x10 is defined on x86_64 in long | |
449 | * mode (i.e. even for 32-bit userspace software, but | |
450 | * 64-bit kernel), so the x86_64 mask value is 0x5454. | |
451 | * See the AMD manual no. 24593 (AMD64 System | |
452 | * Programming)*/ | |
453 | ||
454 | if(addr == (long) &dummy->u_debugreg[7]) { | |
455 | data &= ~DR_CONTROL_RESERVED; | |
456 | for(i=0; i<4; i++) | |
457 | if ((0x5f54 >> ((data >> (16 + 4*i)) & 0xf)) & 1) | |
458 | goto out_tsk; | |
b3cf2576 SE |
459 | if (data) |
460 | set_tsk_thread_flag(child, TIF_DEBUG); | |
461 | else | |
462 | clear_tsk_thread_flag(child, TIF_DEBUG); | |
1da177e4 | 463 | } |
1da177e4 LT |
464 | addr -= (long) &dummy->u_debugreg; |
465 | addr = addr >> 2; | |
466 | child->thread.debugreg[addr] = data; | |
467 | ret = 0; | |
468 | } | |
469 | break; | |
470 | ||
ed75e8d5 | 471 | case PTRACE_SYSEMU: /* continue and stop at next syscall, which will not be executed */ |
1da177e4 LT |
472 | case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */ |
473 | case PTRACE_CONT: /* restart after signal. */ | |
474 | ret = -EIO; | |
7ed20e1a | 475 | if (!valid_signal(data)) |
1da177e4 | 476 | break; |
ed75e8d5 LV |
477 | if (request == PTRACE_SYSEMU) { |
478 | set_tsk_thread_flag(child, TIF_SYSCALL_EMU); | |
c8c86cec BS |
479 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
480 | } else if (request == PTRACE_SYSCALL) { | |
1da177e4 | 481 | set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
c8c86cec | 482 | clear_tsk_thread_flag(child, TIF_SYSCALL_EMU); |
ed75e8d5 | 483 | } else { |
c8c86cec | 484 | clear_tsk_thread_flag(child, TIF_SYSCALL_EMU); |
1da177e4 LT |
485 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
486 | } | |
487 | child->exit_code = data; | |
488 | /* make sure the single step bit is not set. */ | |
489 | clear_singlestep(child); | |
490 | wake_up_process(child); | |
491 | ret = 0; | |
492 | break; | |
493 | ||
494 | /* | |
495 | * make the child exit. Best I can do is send it a sigkill. | |
496 | * perhaps it should be put in the status that it wants to | |
497 | * exit. | |
498 | */ | |
499 | case PTRACE_KILL: | |
500 | ret = 0; | |
501 | if (child->exit_state == EXIT_ZOMBIE) /* already dead */ | |
502 | break; | |
503 | child->exit_code = SIGKILL; | |
504 | /* make sure the single step bit is not set. */ | |
505 | clear_singlestep(child); | |
506 | wake_up_process(child); | |
507 | break; | |
508 | ||
1b38f006 | 509 | case PTRACE_SYSEMU_SINGLESTEP: /* Same as SYSEMU, but singlestep if not syscall */ |
1da177e4 LT |
510 | case PTRACE_SINGLESTEP: /* set the trap flag. */ |
511 | ret = -EIO; | |
7ed20e1a | 512 | if (!valid_signal(data)) |
1da177e4 | 513 | break; |
1b38f006 BS |
514 | |
515 | if (request == PTRACE_SYSEMU_SINGLESTEP) | |
516 | set_tsk_thread_flag(child, TIF_SYSCALL_EMU); | |
517 | else | |
518 | clear_tsk_thread_flag(child, TIF_SYSCALL_EMU); | |
519 | ||
1da177e4 LT |
520 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
521 | set_singlestep(child); | |
522 | child->exit_code = data; | |
523 | /* give it a chance to run. */ | |
524 | wake_up_process(child); | |
525 | ret = 0; | |
526 | break; | |
527 | ||
528 | case PTRACE_DETACH: | |
529 | /* detach a process that was attached. */ | |
530 | ret = ptrace_detach(child, data); | |
531 | break; | |
532 | ||
533 | case PTRACE_GETREGS: { /* Get all gp regs from the child. */ | |
534 | if (!access_ok(VERIFY_WRITE, datap, FRAME_SIZE*sizeof(long))) { | |
535 | ret = -EIO; | |
536 | break; | |
537 | } | |
538 | for ( i = 0; i < FRAME_SIZE*sizeof(long); i += sizeof(long) ) { | |
539 | __put_user(getreg(child, i), datap); | |
540 | datap++; | |
541 | } | |
542 | ret = 0; | |
543 | break; | |
544 | } | |
545 | ||
546 | case PTRACE_SETREGS: { /* Set all gp regs in the child. */ | |
547 | unsigned long tmp; | |
548 | if (!access_ok(VERIFY_READ, datap, FRAME_SIZE*sizeof(long))) { | |
549 | ret = -EIO; | |
550 | break; | |
551 | } | |
552 | for ( i = 0; i < FRAME_SIZE*sizeof(long); i += sizeof(long) ) { | |
553 | __get_user(tmp, datap); | |
554 | putreg(child, i, tmp); | |
555 | datap++; | |
556 | } | |
557 | ret = 0; | |
558 | break; | |
559 | } | |
560 | ||
561 | case PTRACE_GETFPREGS: { /* Get the child FPU state. */ | |
562 | if (!access_ok(VERIFY_WRITE, datap, | |
563 | sizeof(struct user_i387_struct))) { | |
564 | ret = -EIO; | |
565 | break; | |
566 | } | |
567 | ret = 0; | |
568 | if (!tsk_used_math(child)) | |
569 | init_fpu(child); | |
570 | get_fpregs((struct user_i387_struct __user *)data, child); | |
571 | break; | |
572 | } | |
573 | ||
574 | case PTRACE_SETFPREGS: { /* Set the child FPU state. */ | |
575 | if (!access_ok(VERIFY_READ, datap, | |
576 | sizeof(struct user_i387_struct))) { | |
577 | ret = -EIO; | |
578 | break; | |
579 | } | |
580 | set_stopped_child_used_math(child); | |
581 | set_fpregs(child, (struct user_i387_struct __user *)data); | |
582 | ret = 0; | |
583 | break; | |
584 | } | |
585 | ||
586 | case PTRACE_GETFPXREGS: { /* Get the child extended FPU state. */ | |
587 | if (!access_ok(VERIFY_WRITE, datap, | |
588 | sizeof(struct user_fxsr_struct))) { | |
589 | ret = -EIO; | |
590 | break; | |
591 | } | |
592 | if (!tsk_used_math(child)) | |
593 | init_fpu(child); | |
594 | ret = get_fpxregs((struct user_fxsr_struct __user *)data, child); | |
595 | break; | |
596 | } | |
597 | ||
598 | case PTRACE_SETFPXREGS: { /* Set the child extended FPU state. */ | |
599 | if (!access_ok(VERIFY_READ, datap, | |
600 | sizeof(struct user_fxsr_struct))) { | |
601 | ret = -EIO; | |
602 | break; | |
603 | } | |
604 | set_stopped_child_used_math(child); | |
605 | ret = set_fpxregs(child, (struct user_fxsr_struct __user *)data); | |
606 | break; | |
607 | } | |
608 | ||
609 | case PTRACE_GET_THREAD_AREA: | |
610 | ret = ptrace_get_thread_area(child, addr, | |
611 | (struct user_desc __user *) data); | |
612 | break; | |
613 | ||
614 | case PTRACE_SET_THREAD_AREA: | |
615 | ret = ptrace_set_thread_area(child, addr, | |
616 | (struct user_desc __user *) data); | |
617 | break; | |
618 | ||
619 | default: | |
620 | ret = ptrace_request(child, request, addr, data); | |
621 | break; | |
622 | } | |
481bed45 | 623 | out_tsk: |
1da177e4 LT |
624 | return ret; |
625 | } | |
626 | ||
627 | void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code) | |
628 | { | |
629 | struct siginfo info; | |
630 | ||
631 | tsk->thread.trap_no = 1; | |
632 | tsk->thread.error_code = error_code; | |
633 | ||
634 | memset(&info, 0, sizeof(info)); | |
635 | info.si_signo = SIGTRAP; | |
636 | info.si_code = TRAP_BRKPT; | |
637 | ||
638 | /* User-mode eip? */ | |
fa1e1bdf | 639 | info.si_addr = user_mode_vm(regs) ? (void __user *) regs->eip : NULL; |
1da177e4 LT |
640 | |
641 | /* Send us the fakey SIGTRAP */ | |
642 | force_sig_info(SIGTRAP, &info, tsk); | |
643 | } | |
644 | ||
645 | /* notification of system call entry/exit | |
646 | * - triggered by current->work.syscall_trace | |
647 | */ | |
648 | __attribute__((regparm(3))) | |
ed75e8d5 | 649 | int do_syscall_trace(struct pt_regs *regs, int entryexit) |
1da177e4 | 650 | { |
4c7fc722 AA |
651 | int is_sysemu = test_thread_flag(TIF_SYSCALL_EMU); |
652 | /* | |
653 | * With TIF_SYSCALL_EMU set we want to ignore TIF_SINGLESTEP for syscall | |
654 | * interception | |
655 | */ | |
1b38f006 | 656 | int is_singlestep = !is_sysemu && test_thread_flag(TIF_SINGLESTEP); |
4c7fc722 | 657 | int ret = 0; |
1b38f006 | 658 | |
1da177e4 | 659 | /* do the secure computing check first */ |
4c7fc722 AA |
660 | if (!entryexit) |
661 | secure_computing(regs->orig_eax); | |
1da177e4 | 662 | |
ab1c23c2 BS |
663 | if (unlikely(current->audit_context)) { |
664 | if (entryexit) | |
5411be59 | 665 | audit_syscall_exit(AUDITSC_RESULT(regs->eax), |
4c7fc722 | 666 | regs->eax); |
ab1c23c2 BS |
667 | /* Debug traps, when using PTRACE_SINGLESTEP, must be sent only |
668 | * on the syscall exit path. Normally, when TIF_SYSCALL_AUDIT is | |
669 | * not used, entry.S will call us only on syscall exit, not | |
670 | * entry; so when TIF_SYSCALL_AUDIT is used we must avoid | |
671 | * calling send_sigtrap() on syscall entry. | |
672 | * | |
673 | * Note that when PTRACE_SYSEMU_SINGLESTEP is used, | |
674 | * is_singlestep is false, despite his name, so we will still do | |
675 | * the correct thing. | |
676 | */ | |
677 | else if (is_singlestep) | |
678 | goto out; | |
679 | } | |
1da177e4 LT |
680 | |
681 | if (!(current->ptrace & PT_PTRACED)) | |
2fd6f58b | 682 | goto out; |
1da177e4 | 683 | |
1b38f006 BS |
684 | /* If a process stops on the 1st tracepoint with SYSCALL_TRACE |
685 | * and then is resumed with SYSEMU_SINGLESTEP, it will come in | |
686 | * here. We have to check this and return */ | |
687 | if (is_sysemu && entryexit) | |
688 | return 0; | |
ed75e8d5 | 689 | |
1da177e4 | 690 | /* Fake a debug trap */ |
c8c86cec | 691 | if (is_singlestep) |
1da177e4 LT |
692 | send_sigtrap(current, regs, 0); |
693 | ||
c8c86cec | 694 | if (!test_thread_flag(TIF_SYSCALL_TRACE) && !is_sysemu) |
2fd6f58b | 695 | goto out; |
1da177e4 LT |
696 | |
697 | /* the 0x80 provides a way for the tracing parent to distinguish | |
698 | between a syscall stop and SIGTRAP delivery */ | |
ed75e8d5 | 699 | /* Note that the debugger could change the result of test_thread_flag!*/ |
4c7fc722 | 700 | ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) ? 0x80:0)); |
1da177e4 LT |
701 | |
702 | /* | |
703 | * this isn't the same as continuing with a signal, but it will do | |
704 | * for normal use. strace only continues with a signal if the | |
705 | * stopping signal is not SIGTRAP. -brl | |
706 | */ | |
707 | if (current->exit_code) { | |
708 | send_sig(current->exit_code, current, 1); | |
709 | current->exit_code = 0; | |
710 | } | |
ed75e8d5 | 711 | ret = is_sysemu; |
4c7fc722 | 712 | out: |
2fd6f58b | 713 | if (unlikely(current->audit_context) && !entryexit) |
5411be59 | 714 | audit_syscall_entry(AUDIT_ARCH_I386, regs->orig_eax, |
2fd6f58b | 715 | regs->ebx, regs->ecx, regs->edx, regs->esi); |
c8c86cec BS |
716 | if (ret == 0) |
717 | return 0; | |
718 | ||
1b38f006 | 719 | regs->orig_eax = -1; /* force skip of syscall restarting */ |
c8c86cec | 720 | if (unlikely(current->audit_context)) |
5411be59 | 721 | audit_syscall_exit(AUDITSC_RESULT(regs->eax), regs->eax); |
c8c86cec | 722 | return 1; |
1da177e4 | 723 | } |