x86, 32-bit: trim memory not covered by wb mtrrs
[deliverable/linux.git] / arch / x86 / kernel / ptrace.c
1 /* By Ross Biro 1/23/92 */
2 /*
3 * Pentium III FXSR, SSE support
4 * Gareth Hughes <gareth@valinux.com>, May 2000
5 *
6 * BTS tracing
7 * Markus Metzger <markus.t.metzger@intel.com>, Dec 2007
8 */
9
10 #include <linux/kernel.h>
11 #include <linux/sched.h>
12 #include <linux/mm.h>
13 #include <linux/smp.h>
14 #include <linux/errno.h>
15 #include <linux/ptrace.h>
16 #include <linux/regset.h>
17 #include <linux/user.h>
18 #include <linux/elf.h>
19 #include <linux/security.h>
20 #include <linux/audit.h>
21 #include <linux/seccomp.h>
22 #include <linux/signal.h>
23
24 #include <asm/uaccess.h>
25 #include <asm/pgtable.h>
26 #include <asm/system.h>
27 #include <asm/processor.h>
28 #include <asm/i387.h>
29 #include <asm/debugreg.h>
30 #include <asm/ldt.h>
31 #include <asm/desc.h>
32 #include <asm/prctl.h>
33 #include <asm/proto.h>
34 #include <asm/ds.h>
35
36 #include "tls.h"
37
38 enum x86_regset {
39 REGSET_GENERAL,
40 REGSET_FP,
41 REGSET_XFP,
42 REGSET_TLS,
43 };
44
45 /*
46 * does not yet catch signals sent when the child dies.
47 * in exit.c or in signal.c.
48 */
49
50 /*
51 * Determines which flags the user has access to [1 = access, 0 = no access].
52 */
53 #define FLAG_MASK_32 ((unsigned long) \
54 (X86_EFLAGS_CF | X86_EFLAGS_PF | \
55 X86_EFLAGS_AF | X86_EFLAGS_ZF | \
56 X86_EFLAGS_SF | X86_EFLAGS_TF | \
57 X86_EFLAGS_DF | X86_EFLAGS_OF | \
58 X86_EFLAGS_RF | X86_EFLAGS_AC))
59
60 /*
61 * Determines whether a value may be installed in a segment register.
62 */
63 static inline bool invalid_selector(u16 value)
64 {
65 return unlikely(value != 0 && (value & SEGMENT_RPL_MASK) != USER_RPL);
66 }
67
68 #ifdef CONFIG_X86_32
69
70 #define FLAG_MASK FLAG_MASK_32
71
72 static long *pt_regs_access(struct pt_regs *regs, unsigned long regno)
73 {
74 BUILD_BUG_ON(offsetof(struct pt_regs, bx) != 0);
75 regno >>= 2;
76 if (regno > FS)
77 --regno;
78 return &regs->bx + regno;
79 }
80
81 static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
82 {
83 /*
84 * Returning the value truncates it to 16 bits.
85 */
86 unsigned int retval;
87 if (offset != offsetof(struct user_regs_struct, gs))
88 retval = *pt_regs_access(task_pt_regs(task), offset);
89 else {
90 retval = task->thread.gs;
91 if (task == current)
92 savesegment(gs, retval);
93 }
94 return retval;
95 }
96
97 static int set_segment_reg(struct task_struct *task,
98 unsigned long offset, u16 value)
99 {
100 /*
101 * The value argument was already truncated to 16 bits.
102 */
103 if (invalid_selector(value))
104 return -EIO;
105
106 if (offset != offsetof(struct user_regs_struct, gs))
107 *pt_regs_access(task_pt_regs(task), offset) = value;
108 else {
109 task->thread.gs = value;
110 if (task == current)
111 /*
112 * The user-mode %gs is not affected by
113 * kernel entry, so we must update the CPU.
114 */
115 loadsegment(gs, value);
116 }
117
118 return 0;
119 }
120
121 static unsigned long debugreg_addr_limit(struct task_struct *task)
122 {
123 return TASK_SIZE - 3;
124 }
125
126 #else /* CONFIG_X86_64 */
127
128 #define FLAG_MASK (FLAG_MASK_32 | X86_EFLAGS_NT)
129
130 static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long offset)
131 {
132 BUILD_BUG_ON(offsetof(struct pt_regs, r15) != 0);
133 return &regs->r15 + (offset / sizeof(regs->r15));
134 }
135
136 static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
137 {
138 /*
139 * Returning the value truncates it to 16 bits.
140 */
141 unsigned int seg;
142
143 switch (offset) {
144 case offsetof(struct user_regs_struct, fs):
145 if (task == current) {
146 /* Older gas can't assemble movq %?s,%r?? */
147 asm("movl %%fs,%0" : "=r" (seg));
148 return seg;
149 }
150 return task->thread.fsindex;
151 case offsetof(struct user_regs_struct, gs):
152 if (task == current) {
153 asm("movl %%gs,%0" : "=r" (seg));
154 return seg;
155 }
156 return task->thread.gsindex;
157 case offsetof(struct user_regs_struct, ds):
158 if (task == current) {
159 asm("movl %%ds,%0" : "=r" (seg));
160 return seg;
161 }
162 return task->thread.ds;
163 case offsetof(struct user_regs_struct, es):
164 if (task == current) {
165 asm("movl %%es,%0" : "=r" (seg));
166 return seg;
167 }
168 return task->thread.es;
169
170 case offsetof(struct user_regs_struct, cs):
171 case offsetof(struct user_regs_struct, ss):
172 break;
173 }
174 return *pt_regs_access(task_pt_regs(task), offset);
175 }
176
177 static int set_segment_reg(struct task_struct *task,
178 unsigned long offset, u16 value)
179 {
180 /*
181 * The value argument was already truncated to 16 bits.
182 */
183 if (invalid_selector(value))
184 return -EIO;
185
186 switch (offset) {
187 case offsetof(struct user_regs_struct,fs):
188 /*
189 * If this is setting fs as for normal 64-bit use but
190 * setting fs_base has implicitly changed it, leave it.
191 */
192 if ((value == FS_TLS_SEL && task->thread.fsindex == 0 &&
193 task->thread.fs != 0) ||
194 (value == 0 && task->thread.fsindex == FS_TLS_SEL &&
195 task->thread.fs == 0))
196 break;
197 task->thread.fsindex = value;
198 if (task == current)
199 loadsegment(fs, task->thread.fsindex);
200 break;
201 case offsetof(struct user_regs_struct,gs):
202 /*
203 * If this is setting gs as for normal 64-bit use but
204 * setting gs_base has implicitly changed it, leave it.
205 */
206 if ((value == GS_TLS_SEL && task->thread.gsindex == 0 &&
207 task->thread.gs != 0) ||
208 (value == 0 && task->thread.gsindex == GS_TLS_SEL &&
209 task->thread.gs == 0))
210 break;
211 task->thread.gsindex = value;
212 if (task == current)
213 load_gs_index(task->thread.gsindex);
214 break;
215 case offsetof(struct user_regs_struct,ds):
216 task->thread.ds = value;
217 if (task == current)
218 loadsegment(ds, task->thread.ds);
219 break;
220 case offsetof(struct user_regs_struct,es):
221 task->thread.es = value;
222 if (task == current)
223 loadsegment(es, task->thread.es);
224 break;
225
226 /*
227 * Can't actually change these in 64-bit mode.
228 */
229 case offsetof(struct user_regs_struct,cs):
230 #ifdef CONFIG_IA32_EMULATION
231 if (test_tsk_thread_flag(task, TIF_IA32))
232 task_pt_regs(task)->cs = value;
233 #endif
234 break;
235 case offsetof(struct user_regs_struct,ss):
236 #ifdef CONFIG_IA32_EMULATION
237 if (test_tsk_thread_flag(task, TIF_IA32))
238 task_pt_regs(task)->ss = value;
239 #endif
240 break;
241 }
242
243 return 0;
244 }
245
246 static unsigned long debugreg_addr_limit(struct task_struct *task)
247 {
248 #ifdef CONFIG_IA32_EMULATION
249 if (test_tsk_thread_flag(task, TIF_IA32))
250 return IA32_PAGE_OFFSET - 3;
251 #endif
252 return TASK_SIZE64 - 7;
253 }
254
255 #endif /* CONFIG_X86_32 */
256
257 static unsigned long get_flags(struct task_struct *task)
258 {
259 unsigned long retval = task_pt_regs(task)->flags;
260
261 /*
262 * If the debugger set TF, hide it from the readout.
263 */
264 if (test_tsk_thread_flag(task, TIF_FORCED_TF))
265 retval &= ~X86_EFLAGS_TF;
266
267 return retval;
268 }
269
270 static int set_flags(struct task_struct *task, unsigned long value)
271 {
272 struct pt_regs *regs = task_pt_regs(task);
273
274 /*
275 * If the user value contains TF, mark that
276 * it was not "us" (the debugger) that set it.
277 * If not, make sure it stays set if we had.
278 */
279 if (value & X86_EFLAGS_TF)
280 clear_tsk_thread_flag(task, TIF_FORCED_TF);
281 else if (test_tsk_thread_flag(task, TIF_FORCED_TF))
282 value |= X86_EFLAGS_TF;
283
284 regs->flags = (regs->flags & ~FLAG_MASK) | (value & FLAG_MASK);
285
286 return 0;
287 }
288
289 static int putreg(struct task_struct *child,
290 unsigned long offset, unsigned long value)
291 {
292 switch (offset) {
293 case offsetof(struct user_regs_struct, cs):
294 case offsetof(struct user_regs_struct, ds):
295 case offsetof(struct user_regs_struct, es):
296 case offsetof(struct user_regs_struct, fs):
297 case offsetof(struct user_regs_struct, gs):
298 case offsetof(struct user_regs_struct, ss):
299 return set_segment_reg(child, offset, value);
300
301 case offsetof(struct user_regs_struct, flags):
302 return set_flags(child, value);
303
304 #ifdef CONFIG_X86_64
305 case offsetof(struct user_regs_struct,fs_base):
306 if (value >= TASK_SIZE_OF(child))
307 return -EIO;
308 /*
309 * When changing the segment base, use do_arch_prctl
310 * to set either thread.fs or thread.fsindex and the
311 * corresponding GDT slot.
312 */
313 if (child->thread.fs != value)
314 return do_arch_prctl(child, ARCH_SET_FS, value);
315 return 0;
316 case offsetof(struct user_regs_struct,gs_base):
317 /*
318 * Exactly the same here as the %fs handling above.
319 */
320 if (value >= TASK_SIZE_OF(child))
321 return -EIO;
322 if (child->thread.gs != value)
323 return do_arch_prctl(child, ARCH_SET_GS, value);
324 return 0;
325 #endif
326 }
327
328 *pt_regs_access(task_pt_regs(child), offset) = value;
329 return 0;
330 }
331
332 static unsigned long getreg(struct task_struct *task, unsigned long offset)
333 {
334 switch (offset) {
335 case offsetof(struct user_regs_struct, cs):
336 case offsetof(struct user_regs_struct, ds):
337 case offsetof(struct user_regs_struct, es):
338 case offsetof(struct user_regs_struct, fs):
339 case offsetof(struct user_regs_struct, gs):
340 case offsetof(struct user_regs_struct, ss):
341 return get_segment_reg(task, offset);
342
343 case offsetof(struct user_regs_struct, flags):
344 return get_flags(task);
345
346 #ifdef CONFIG_X86_64
347 case offsetof(struct user_regs_struct, fs_base): {
348 /*
349 * do_arch_prctl may have used a GDT slot instead of
350 * the MSR. To userland, it appears the same either
351 * way, except the %fs segment selector might not be 0.
352 */
353 unsigned int seg = task->thread.fsindex;
354 if (task->thread.fs != 0)
355 return task->thread.fs;
356 if (task == current)
357 asm("movl %%fs,%0" : "=r" (seg));
358 if (seg != FS_TLS_SEL)
359 return 0;
360 return get_desc_base(&task->thread.tls_array[FS_TLS]);
361 }
362 case offsetof(struct user_regs_struct, gs_base): {
363 /*
364 * Exactly the same here as the %fs handling above.
365 */
366 unsigned int seg = task->thread.gsindex;
367 if (task->thread.gs != 0)
368 return task->thread.gs;
369 if (task == current)
370 asm("movl %%gs,%0" : "=r" (seg));
371 if (seg != GS_TLS_SEL)
372 return 0;
373 return get_desc_base(&task->thread.tls_array[GS_TLS]);
374 }
375 #endif
376 }
377
378 return *pt_regs_access(task_pt_regs(task), offset);
379 }
380
381 static int genregs_get(struct task_struct *target,
382 const struct user_regset *regset,
383 unsigned int pos, unsigned int count,
384 void *kbuf, void __user *ubuf)
385 {
386 if (kbuf) {
387 unsigned long *k = kbuf;
388 while (count > 0) {
389 *k++ = getreg(target, pos);
390 count -= sizeof(*k);
391 pos += sizeof(*k);
392 }
393 } else {
394 unsigned long __user *u = ubuf;
395 while (count > 0) {
396 if (__put_user(getreg(target, pos), u++))
397 return -EFAULT;
398 count -= sizeof(*u);
399 pos += sizeof(*u);
400 }
401 }
402
403 return 0;
404 }
405
406 static int genregs_set(struct task_struct *target,
407 const struct user_regset *regset,
408 unsigned int pos, unsigned int count,
409 const void *kbuf, const void __user *ubuf)
410 {
411 int ret = 0;
412 if (kbuf) {
413 const unsigned long *k = kbuf;
414 while (count > 0 && !ret) {
415 ret = putreg(target, pos, *k++);
416 count -= sizeof(*k);
417 pos += sizeof(*k);
418 }
419 } else {
420 const unsigned long __user *u = ubuf;
421 while (count > 0 && !ret) {
422 unsigned long word;
423 ret = __get_user(word, u++);
424 if (ret)
425 break;
426 ret = putreg(target, pos, word);
427 count -= sizeof(*u);
428 pos += sizeof(*u);
429 }
430 }
431 return ret;
432 }
433
434 /*
435 * This function is trivial and will be inlined by the compiler.
436 * Having it separates the implementation details of debug
437 * registers from the interface details of ptrace.
438 */
439 static unsigned long ptrace_get_debugreg(struct task_struct *child, int n)
440 {
441 switch (n) {
442 case 0: return child->thread.debugreg0;
443 case 1: return child->thread.debugreg1;
444 case 2: return child->thread.debugreg2;
445 case 3: return child->thread.debugreg3;
446 case 6: return child->thread.debugreg6;
447 case 7: return child->thread.debugreg7;
448 }
449 return 0;
450 }
451
452 static int ptrace_set_debugreg(struct task_struct *child,
453 int n, unsigned long data)
454 {
455 int i;
456
457 if (unlikely(n == 4 || n == 5))
458 return -EIO;
459
460 if (n < 4 && unlikely(data >= debugreg_addr_limit(child)))
461 return -EIO;
462
463 switch (n) {
464 case 0: child->thread.debugreg0 = data; break;
465 case 1: child->thread.debugreg1 = data; break;
466 case 2: child->thread.debugreg2 = data; break;
467 case 3: child->thread.debugreg3 = data; break;
468
469 case 6:
470 if ((data & ~0xffffffffUL) != 0)
471 return -EIO;
472 child->thread.debugreg6 = data;
473 break;
474
475 case 7:
476 /*
477 * Sanity-check data. Take one half-byte at once with
478 * check = (val >> (16 + 4*i)) & 0xf. It contains the
479 * R/Wi and LENi bits; bits 0 and 1 are R/Wi, and bits
480 * 2 and 3 are LENi. Given a list of invalid values,
481 * we do mask |= 1 << invalid_value, so that
482 * (mask >> check) & 1 is a correct test for invalid
483 * values.
484 *
485 * R/Wi contains the type of the breakpoint /
486 * watchpoint, LENi contains the length of the watched
487 * data in the watchpoint case.
488 *
489 * The invalid values are:
490 * - LENi == 0x10 (undefined), so mask |= 0x0f00. [32-bit]
491 * - R/Wi == 0x10 (break on I/O reads or writes), so
492 * mask |= 0x4444.
493 * - R/Wi == 0x00 && LENi != 0x00, so we have mask |=
494 * 0x1110.
495 *
496 * Finally, mask = 0x0f00 | 0x4444 | 0x1110 == 0x5f54.
497 *
498 * See the Intel Manual "System Programming Guide",
499 * 15.2.4
500 *
501 * Note that LENi == 0x10 is defined on x86_64 in long
502 * mode (i.e. even for 32-bit userspace software, but
503 * 64-bit kernel), so the x86_64 mask value is 0x5454.
504 * See the AMD manual no. 24593 (AMD64 System Programming)
505 */
506 #ifdef CONFIG_X86_32
507 #define DR7_MASK 0x5f54
508 #else
509 #define DR7_MASK 0x5554
510 #endif
511 data &= ~DR_CONTROL_RESERVED;
512 for (i = 0; i < 4; i++)
513 if ((DR7_MASK >> ((data >> (16 + 4*i)) & 0xf)) & 1)
514 return -EIO;
515 child->thread.debugreg7 = data;
516 if (data)
517 set_tsk_thread_flag(child, TIF_DEBUG);
518 else
519 clear_tsk_thread_flag(child, TIF_DEBUG);
520 break;
521 }
522
523 return 0;
524 }
525
526 static int ptrace_bts_get_size(struct task_struct *child)
527 {
528 if (!child->thread.ds_area_msr)
529 return -ENXIO;
530
531 return ds_get_bts_index((void *)child->thread.ds_area_msr);
532 }
533
534 static int ptrace_bts_read_record(struct task_struct *child,
535 long index,
536 struct bts_struct __user *out)
537 {
538 struct bts_struct ret;
539 int retval;
540 int bts_end;
541 int bts_index;
542
543 if (!child->thread.ds_area_msr)
544 return -ENXIO;
545
546 if (index < 0)
547 return -EINVAL;
548
549 bts_end = ds_get_bts_end((void *)child->thread.ds_area_msr);
550 if (bts_end <= index)
551 return -EINVAL;
552
553 /* translate the ptrace bts index into the ds bts index */
554 bts_index = ds_get_bts_index((void *)child->thread.ds_area_msr);
555 bts_index -= (index + 1);
556 if (bts_index < 0)
557 bts_index += bts_end;
558
559 retval = ds_read_bts((void *)child->thread.ds_area_msr,
560 bts_index, &ret);
561 if (retval < 0)
562 return retval;
563
564 if (copy_to_user(out, &ret, sizeof(ret)))
565 return -EFAULT;
566
567 return sizeof(ret);
568 }
569
570 static int ptrace_bts_write_record(struct task_struct *child,
571 const struct bts_struct *in)
572 {
573 int retval;
574
575 if (!child->thread.ds_area_msr)
576 return -ENXIO;
577
578 retval = ds_write_bts((void *)child->thread.ds_area_msr, in);
579 if (retval)
580 return retval;
581
582 return sizeof(*in);
583 }
584
585 static int ptrace_bts_clear(struct task_struct *child)
586 {
587 if (!child->thread.ds_area_msr)
588 return -ENXIO;
589
590 return ds_clear((void *)child->thread.ds_area_msr);
591 }
592
593 static int ptrace_bts_drain(struct task_struct *child,
594 long size,
595 struct bts_struct __user *out)
596 {
597 int end, i;
598 void *ds = (void *)child->thread.ds_area_msr;
599
600 if (!ds)
601 return -ENXIO;
602
603 end = ds_get_bts_index(ds);
604 if (end <= 0)
605 return end;
606
607 if (size < (end * sizeof(struct bts_struct)))
608 return -EIO;
609
610 for (i = 0; i < end; i++, out++) {
611 struct bts_struct ret;
612 int retval;
613
614 retval = ds_read_bts(ds, i, &ret);
615 if (retval < 0)
616 return retval;
617
618 if (copy_to_user(out, &ret, sizeof(ret)))
619 return -EFAULT;
620 }
621
622 ds_clear(ds);
623
624 return end;
625 }
626
627 static int ptrace_bts_realloc(struct task_struct *child,
628 int size, int reduce_size)
629 {
630 unsigned long rlim, vm;
631 int ret, old_size;
632
633 if (size < 0)
634 return -EINVAL;
635
636 old_size = ds_get_bts_size((void *)child->thread.ds_area_msr);
637 if (old_size < 0)
638 return old_size;
639
640 ret = ds_free((void **)&child->thread.ds_area_msr);
641 if (ret < 0)
642 goto out;
643
644 size >>= PAGE_SHIFT;
645 old_size >>= PAGE_SHIFT;
646
647 current->mm->total_vm -= old_size;
648 current->mm->locked_vm -= old_size;
649
650 if (size == 0)
651 goto out;
652
653 rlim = current->signal->rlim[RLIMIT_AS].rlim_cur >> PAGE_SHIFT;
654 vm = current->mm->total_vm + size;
655 if (rlim < vm) {
656 ret = -ENOMEM;
657
658 if (!reduce_size)
659 goto out;
660
661 size = rlim - current->mm->total_vm;
662 if (size <= 0)
663 goto out;
664 }
665
666 rlim = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT;
667 vm = current->mm->locked_vm + size;
668 if (rlim < vm) {
669 ret = -ENOMEM;
670
671 if (!reduce_size)
672 goto out;
673
674 size = rlim - current->mm->locked_vm;
675 if (size <= 0)
676 goto out;
677 }
678
679 ret = ds_allocate((void **)&child->thread.ds_area_msr,
680 size << PAGE_SHIFT);
681 if (ret < 0)
682 goto out;
683
684 current->mm->total_vm += size;
685 current->mm->locked_vm += size;
686
687 out:
688 if (child->thread.ds_area_msr)
689 set_tsk_thread_flag(child, TIF_DS_AREA_MSR);
690 else
691 clear_tsk_thread_flag(child, TIF_DS_AREA_MSR);
692
693 return ret;
694 }
695
696 static int ptrace_bts_config(struct task_struct *child,
697 long cfg_size,
698 const struct ptrace_bts_config __user *ucfg)
699 {
700 struct ptrace_bts_config cfg;
701 int bts_size, ret = 0;
702 void *ds;
703
704 if (cfg_size < sizeof(cfg))
705 return -EIO;
706
707 if (copy_from_user(&cfg, ucfg, sizeof(cfg)))
708 return -EFAULT;
709
710 if ((int)cfg.size < 0)
711 return -EINVAL;
712
713 bts_size = 0;
714 ds = (void *)child->thread.ds_area_msr;
715 if (ds) {
716 bts_size = ds_get_bts_size(ds);
717 if (bts_size < 0)
718 return bts_size;
719 }
720 cfg.size = PAGE_ALIGN(cfg.size);
721
722 if (bts_size != cfg.size) {
723 ret = ptrace_bts_realloc(child, cfg.size,
724 cfg.flags & PTRACE_BTS_O_CUT_SIZE);
725 if (ret < 0)
726 goto errout;
727
728 ds = (void *)child->thread.ds_area_msr;
729 }
730
731 if (cfg.flags & PTRACE_BTS_O_SIGNAL)
732 ret = ds_set_overflow(ds, DS_O_SIGNAL);
733 else
734 ret = ds_set_overflow(ds, DS_O_WRAP);
735 if (ret < 0)
736 goto errout;
737
738 if (cfg.flags & PTRACE_BTS_O_TRACE)
739 child->thread.debugctlmsr |= ds_debugctl_mask();
740 else
741 child->thread.debugctlmsr &= ~ds_debugctl_mask();
742
743 if (cfg.flags & PTRACE_BTS_O_SCHED)
744 set_tsk_thread_flag(child, TIF_BTS_TRACE_TS);
745 else
746 clear_tsk_thread_flag(child, TIF_BTS_TRACE_TS);
747
748 ret = sizeof(cfg);
749
750 out:
751 if (child->thread.debugctlmsr)
752 set_tsk_thread_flag(child, TIF_DEBUGCTLMSR);
753 else
754 clear_tsk_thread_flag(child, TIF_DEBUGCTLMSR);
755
756 return ret;
757
758 errout:
759 child->thread.debugctlmsr &= ~ds_debugctl_mask();
760 clear_tsk_thread_flag(child, TIF_BTS_TRACE_TS);
761 goto out;
762 }
763
764 static int ptrace_bts_status(struct task_struct *child,
765 long cfg_size,
766 struct ptrace_bts_config __user *ucfg)
767 {
768 void *ds = (void *)child->thread.ds_area_msr;
769 struct ptrace_bts_config cfg;
770
771 if (cfg_size < sizeof(cfg))
772 return -EIO;
773
774 memset(&cfg, 0, sizeof(cfg));
775
776 if (ds) {
777 cfg.size = ds_get_bts_size(ds);
778
779 if (ds_get_overflow(ds) == DS_O_SIGNAL)
780 cfg.flags |= PTRACE_BTS_O_SIGNAL;
781
782 if (test_tsk_thread_flag(child, TIF_DEBUGCTLMSR) &&
783 child->thread.debugctlmsr & ds_debugctl_mask())
784 cfg.flags |= PTRACE_BTS_O_TRACE;
785
786 if (test_tsk_thread_flag(child, TIF_BTS_TRACE_TS))
787 cfg.flags |= PTRACE_BTS_O_SCHED;
788 }
789
790 cfg.bts_size = sizeof(struct bts_struct);
791
792 if (copy_to_user(ucfg, &cfg, sizeof(cfg)))
793 return -EFAULT;
794
795 return sizeof(cfg);
796 }
797
798 void ptrace_bts_take_timestamp(struct task_struct *tsk,
799 enum bts_qualifier qualifier)
800 {
801 struct bts_struct rec = {
802 .qualifier = qualifier,
803 .variant.jiffies = jiffies_64
804 };
805
806 ptrace_bts_write_record(tsk, &rec);
807 }
808
809 /*
810 * Called by kernel/ptrace.c when detaching..
811 *
812 * Make sure the single step bit is not set.
813 */
814 void ptrace_disable(struct task_struct *child)
815 {
816 user_disable_single_step(child);
817 #ifdef TIF_SYSCALL_EMU
818 clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
819 #endif
820 if (child->thread.ds_area_msr) {
821 ptrace_bts_realloc(child, 0, 0);
822 child->thread.debugctlmsr &= ~ds_debugctl_mask();
823 if (!child->thread.debugctlmsr)
824 clear_tsk_thread_flag(child, TIF_DEBUGCTLMSR);
825 clear_tsk_thread_flag(child, TIF_BTS_TRACE_TS);
826 }
827 }
828
829 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
830 static const struct user_regset_view user_x86_32_view; /* Initialized below. */
831 #endif
832
833 long arch_ptrace(struct task_struct *child, long request, long addr, long data)
834 {
835 int ret;
836 unsigned long __user *datap = (unsigned long __user *)data;
837
838 switch (request) {
839 /* read the word at location addr in the USER area. */
840 case PTRACE_PEEKUSR: {
841 unsigned long tmp;
842
843 ret = -EIO;
844 if ((addr & (sizeof(data) - 1)) || addr < 0 ||
845 addr >= sizeof(struct user))
846 break;
847
848 tmp = 0; /* Default return condition */
849 if (addr < sizeof(struct user_regs_struct))
850 tmp = getreg(child, addr);
851 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
852 addr <= offsetof(struct user, u_debugreg[7])) {
853 addr -= offsetof(struct user, u_debugreg[0]);
854 tmp = ptrace_get_debugreg(child, addr / sizeof(data));
855 }
856 ret = put_user(tmp, datap);
857 break;
858 }
859
860 case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
861 ret = -EIO;
862 if ((addr & (sizeof(data) - 1)) || addr < 0 ||
863 addr >= sizeof(struct user))
864 break;
865
866 if (addr < sizeof(struct user_regs_struct))
867 ret = putreg(child, addr, data);
868 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
869 addr <= offsetof(struct user, u_debugreg[7])) {
870 addr -= offsetof(struct user, u_debugreg[0]);
871 ret = ptrace_set_debugreg(child,
872 addr / sizeof(data), data);
873 }
874 break;
875
876 case PTRACE_GETREGS: /* Get all gp regs from the child. */
877 return copy_regset_to_user(child,
878 task_user_regset_view(current),
879 REGSET_GENERAL,
880 0, sizeof(struct user_regs_struct),
881 datap);
882
883 case PTRACE_SETREGS: /* Set all gp regs in the child. */
884 return copy_regset_from_user(child,
885 task_user_regset_view(current),
886 REGSET_GENERAL,
887 0, sizeof(struct user_regs_struct),
888 datap);
889
890 case PTRACE_GETFPREGS: /* Get the child FPU state. */
891 return copy_regset_to_user(child,
892 task_user_regset_view(current),
893 REGSET_FP,
894 0, sizeof(struct user_i387_struct),
895 datap);
896
897 case PTRACE_SETFPREGS: /* Set the child FPU state. */
898 return copy_regset_from_user(child,
899 task_user_regset_view(current),
900 REGSET_FP,
901 0, sizeof(struct user_i387_struct),
902 datap);
903
904 #ifdef CONFIG_X86_32
905 case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
906 return copy_regset_to_user(child, &user_x86_32_view,
907 REGSET_XFP,
908 0, sizeof(struct user_fxsr_struct),
909 datap);
910
911 case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
912 return copy_regset_from_user(child, &user_x86_32_view,
913 REGSET_XFP,
914 0, sizeof(struct user_fxsr_struct),
915 datap);
916 #endif
917
918 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
919 case PTRACE_GET_THREAD_AREA:
920 if (addr < 0)
921 return -EIO;
922 ret = do_get_thread_area(child, addr,
923 (struct user_desc __user *) data);
924 break;
925
926 case PTRACE_SET_THREAD_AREA:
927 if (addr < 0)
928 return -EIO;
929 ret = do_set_thread_area(child, addr,
930 (struct user_desc __user *) data, 0);
931 break;
932 #endif
933
934 #ifdef CONFIG_X86_64
935 /* normal 64bit interface to access TLS data.
936 Works just like arch_prctl, except that the arguments
937 are reversed. */
938 case PTRACE_ARCH_PRCTL:
939 ret = do_arch_prctl(child, data, addr);
940 break;
941 #endif
942
943 case PTRACE_BTS_CONFIG:
944 ret = ptrace_bts_config
945 (child, data, (struct ptrace_bts_config __user *)addr);
946 break;
947
948 case PTRACE_BTS_STATUS:
949 ret = ptrace_bts_status
950 (child, data, (struct ptrace_bts_config __user *)addr);
951 break;
952
953 case PTRACE_BTS_SIZE:
954 ret = ptrace_bts_get_size(child);
955 break;
956
957 case PTRACE_BTS_GET:
958 ret = ptrace_bts_read_record
959 (child, data, (struct bts_struct __user *) addr);
960 break;
961
962 case PTRACE_BTS_CLEAR:
963 ret = ptrace_bts_clear(child);
964 break;
965
966 case PTRACE_BTS_DRAIN:
967 ret = ptrace_bts_drain
968 (child, data, (struct bts_struct __user *) addr);
969 break;
970
971 default:
972 ret = ptrace_request(child, request, addr, data);
973 break;
974 }
975
976 return ret;
977 }
978
979 #ifdef CONFIG_IA32_EMULATION
980
981 #include <linux/compat.h>
982 #include <linux/syscalls.h>
983 #include <asm/ia32.h>
984 #include <asm/user32.h>
985
986 #define R32(l,q) \
987 case offsetof(struct user32, regs.l): \
988 regs->q = value; break
989
990 #define SEG32(rs) \
991 case offsetof(struct user32, regs.rs): \
992 return set_segment_reg(child, \
993 offsetof(struct user_regs_struct, rs), \
994 value); \
995 break
996
997 static int putreg32(struct task_struct *child, unsigned regno, u32 value)
998 {
999 struct pt_regs *regs = task_pt_regs(child);
1000
1001 switch (regno) {
1002
1003 SEG32(cs);
1004 SEG32(ds);
1005 SEG32(es);
1006 SEG32(fs);
1007 SEG32(gs);
1008 SEG32(ss);
1009
1010 R32(ebx, bx);
1011 R32(ecx, cx);
1012 R32(edx, dx);
1013 R32(edi, di);
1014 R32(esi, si);
1015 R32(ebp, bp);
1016 R32(eax, ax);
1017 R32(orig_eax, orig_ax);
1018 R32(eip, ip);
1019 R32(esp, sp);
1020
1021 case offsetof(struct user32, regs.eflags):
1022 return set_flags(child, value);
1023
1024 case offsetof(struct user32, u_debugreg[0]) ...
1025 offsetof(struct user32, u_debugreg[7]):
1026 regno -= offsetof(struct user32, u_debugreg[0]);
1027 return ptrace_set_debugreg(child, regno / 4, value);
1028
1029 default:
1030 if (regno > sizeof(struct user32) || (regno & 3))
1031 return -EIO;
1032
1033 /*
1034 * Other dummy fields in the virtual user structure
1035 * are ignored
1036 */
1037 break;
1038 }
1039 return 0;
1040 }
1041
1042 #undef R32
1043 #undef SEG32
1044
1045 #define R32(l,q) \
1046 case offsetof(struct user32, regs.l): \
1047 *val = regs->q; break
1048
1049 #define SEG32(rs) \
1050 case offsetof(struct user32, regs.rs): \
1051 *val = get_segment_reg(child, \
1052 offsetof(struct user_regs_struct, rs)); \
1053 break
1054
1055 static int getreg32(struct task_struct *child, unsigned regno, u32 *val)
1056 {
1057 struct pt_regs *regs = task_pt_regs(child);
1058
1059 switch (regno) {
1060
1061 SEG32(ds);
1062 SEG32(es);
1063 SEG32(fs);
1064 SEG32(gs);
1065
1066 R32(cs, cs);
1067 R32(ss, ss);
1068 R32(ebx, bx);
1069 R32(ecx, cx);
1070 R32(edx, dx);
1071 R32(edi, di);
1072 R32(esi, si);
1073 R32(ebp, bp);
1074 R32(eax, ax);
1075 R32(orig_eax, orig_ax);
1076 R32(eip, ip);
1077 R32(esp, sp);
1078
1079 case offsetof(struct user32, regs.eflags):
1080 *val = get_flags(child);
1081 break;
1082
1083 case offsetof(struct user32, u_debugreg[0]) ...
1084 offsetof(struct user32, u_debugreg[7]):
1085 regno -= offsetof(struct user32, u_debugreg[0]);
1086 *val = ptrace_get_debugreg(child, regno / 4);
1087 break;
1088
1089 default:
1090 if (regno > sizeof(struct user32) || (regno & 3))
1091 return -EIO;
1092
1093 /*
1094 * Other dummy fields in the virtual user structure
1095 * are ignored
1096 */
1097 *val = 0;
1098 break;
1099 }
1100 return 0;
1101 }
1102
1103 #undef R32
1104 #undef SEG32
1105
1106 static int genregs32_get(struct task_struct *target,
1107 const struct user_regset *regset,
1108 unsigned int pos, unsigned int count,
1109 void *kbuf, void __user *ubuf)
1110 {
1111 if (kbuf) {
1112 compat_ulong_t *k = kbuf;
1113 while (count > 0) {
1114 getreg32(target, pos, k++);
1115 count -= sizeof(*k);
1116 pos += sizeof(*k);
1117 }
1118 } else {
1119 compat_ulong_t __user *u = ubuf;
1120 while (count > 0) {
1121 compat_ulong_t word;
1122 getreg32(target, pos, &word);
1123 if (__put_user(word, u++))
1124 return -EFAULT;
1125 count -= sizeof(*u);
1126 pos += sizeof(*u);
1127 }
1128 }
1129
1130 return 0;
1131 }
1132
1133 static int genregs32_set(struct task_struct *target,
1134 const struct user_regset *regset,
1135 unsigned int pos, unsigned int count,
1136 const void *kbuf, const void __user *ubuf)
1137 {
1138 int ret = 0;
1139 if (kbuf) {
1140 const compat_ulong_t *k = kbuf;
1141 while (count > 0 && !ret) {
1142 ret = putreg(target, pos, *k++);
1143 count -= sizeof(*k);
1144 pos += sizeof(*k);
1145 }
1146 } else {
1147 const compat_ulong_t __user *u = ubuf;
1148 while (count > 0 && !ret) {
1149 compat_ulong_t word;
1150 ret = __get_user(word, u++);
1151 if (ret)
1152 break;
1153 ret = putreg(target, pos, word);
1154 count -= sizeof(*u);
1155 pos += sizeof(*u);
1156 }
1157 }
1158 return ret;
1159 }
1160
1161 static long ptrace32_siginfo(unsigned request, u32 pid, u32 addr, u32 data)
1162 {
1163 siginfo_t __user *si = compat_alloc_user_space(sizeof(siginfo_t));
1164 compat_siginfo_t __user *si32 = compat_ptr(data);
1165 siginfo_t ssi;
1166 int ret;
1167
1168 if (request == PTRACE_SETSIGINFO) {
1169 memset(&ssi, 0, sizeof(siginfo_t));
1170 ret = copy_siginfo_from_user32(&ssi, si32);
1171 if (ret)
1172 return ret;
1173 if (copy_to_user(si, &ssi, sizeof(siginfo_t)))
1174 return -EFAULT;
1175 }
1176 ret = sys_ptrace(request, pid, addr, (unsigned long)si);
1177 if (ret)
1178 return ret;
1179 if (request == PTRACE_GETSIGINFO) {
1180 if (copy_from_user(&ssi, si, sizeof(siginfo_t)))
1181 return -EFAULT;
1182 ret = copy_siginfo_to_user32(si32, &ssi);
1183 }
1184 return ret;
1185 }
1186
1187 asmlinkage long sys32_ptrace(long request, u32 pid, u32 addr, u32 data)
1188 {
1189 struct task_struct *child;
1190 struct pt_regs *childregs;
1191 void __user *datap = compat_ptr(data);
1192 int ret;
1193 __u32 val;
1194
1195 switch (request) {
1196 case PTRACE_TRACEME:
1197 case PTRACE_ATTACH:
1198 case PTRACE_KILL:
1199 case PTRACE_CONT:
1200 case PTRACE_SINGLESTEP:
1201 case PTRACE_SINGLEBLOCK:
1202 case PTRACE_DETACH:
1203 case PTRACE_SYSCALL:
1204 case PTRACE_OLDSETOPTIONS:
1205 case PTRACE_SETOPTIONS:
1206 case PTRACE_SET_THREAD_AREA:
1207 case PTRACE_GET_THREAD_AREA:
1208 case PTRACE_BTS_CONFIG:
1209 case PTRACE_BTS_STATUS:
1210 case PTRACE_BTS_SIZE:
1211 case PTRACE_BTS_GET:
1212 case PTRACE_BTS_CLEAR:
1213 case PTRACE_BTS_DRAIN:
1214 return sys_ptrace(request, pid, addr, data);
1215
1216 default:
1217 return -EINVAL;
1218
1219 case PTRACE_PEEKTEXT:
1220 case PTRACE_PEEKDATA:
1221 case PTRACE_POKEDATA:
1222 case PTRACE_POKETEXT:
1223 case PTRACE_POKEUSR:
1224 case PTRACE_PEEKUSR:
1225 case PTRACE_GETREGS:
1226 case PTRACE_SETREGS:
1227 case PTRACE_SETFPREGS:
1228 case PTRACE_GETFPREGS:
1229 case PTRACE_SETFPXREGS:
1230 case PTRACE_GETFPXREGS:
1231 case PTRACE_GETEVENTMSG:
1232 break;
1233
1234 case PTRACE_SETSIGINFO:
1235 case PTRACE_GETSIGINFO:
1236 return ptrace32_siginfo(request, pid, addr, data);
1237 }
1238
1239 child = ptrace_get_task_struct(pid);
1240 if (IS_ERR(child))
1241 return PTR_ERR(child);
1242
1243 ret = ptrace_check_attach(child, request == PTRACE_KILL);
1244 if (ret < 0)
1245 goto out;
1246
1247 childregs = task_pt_regs(child);
1248
1249 switch (request) {
1250 case PTRACE_PEEKUSR:
1251 ret = getreg32(child, addr, &val);
1252 if (ret == 0)
1253 ret = put_user(val, (__u32 __user *)datap);
1254 break;
1255
1256 case PTRACE_POKEUSR:
1257 ret = putreg32(child, addr, data);
1258 break;
1259
1260 case PTRACE_GETREGS: /* Get all gp regs from the child. */
1261 return copy_regset_to_user(child, &user_x86_32_view,
1262 REGSET_GENERAL,
1263 0, sizeof(struct user_regs_struct32),
1264 datap);
1265
1266 case PTRACE_SETREGS: /* Set all gp regs in the child. */
1267 return copy_regset_from_user(child, &user_x86_32_view,
1268 REGSET_GENERAL, 0,
1269 sizeof(struct user_regs_struct32),
1270 datap);
1271
1272 case PTRACE_GETFPREGS: /* Get the child FPU state. */
1273 return copy_regset_to_user(child, &user_x86_32_view,
1274 REGSET_FP, 0,
1275 sizeof(struct user_i387_ia32_struct),
1276 datap);
1277
1278 case PTRACE_SETFPREGS: /* Set the child FPU state. */
1279 return copy_regset_from_user(
1280 child, &user_x86_32_view, REGSET_FP,
1281 0, sizeof(struct user_i387_ia32_struct), datap);
1282
1283 case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
1284 return copy_regset_to_user(child, &user_x86_32_view,
1285 REGSET_XFP, 0,
1286 sizeof(struct user32_fxsr_struct),
1287 datap);
1288
1289 case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
1290 return copy_regset_from_user(child, &user_x86_32_view,
1291 REGSET_XFP, 0,
1292 sizeof(struct user32_fxsr_struct),
1293 datap);
1294
1295 default:
1296 return compat_ptrace_request(child, request, addr, data);
1297 }
1298
1299 out:
1300 put_task_struct(child);
1301 return ret;
1302 }
1303
1304 #endif /* CONFIG_IA32_EMULATION */
1305
1306 #ifdef CONFIG_X86_64
1307
1308 static const struct user_regset x86_64_regsets[] = {
1309 [REGSET_GENERAL] = {
1310 .core_note_type = NT_PRSTATUS,
1311 .n = sizeof(struct user_regs_struct) / sizeof(long),
1312 .size = sizeof(long), .align = sizeof(long),
1313 .get = genregs_get, .set = genregs_set
1314 },
1315 [REGSET_FP] = {
1316 .core_note_type = NT_PRFPREG,
1317 .n = sizeof(struct user_i387_struct) / sizeof(long),
1318 .size = sizeof(long), .align = sizeof(long),
1319 .active = xfpregs_active, .get = xfpregs_get, .set = xfpregs_set
1320 },
1321 };
1322
1323 static const struct user_regset_view user_x86_64_view = {
1324 .name = "x86_64", .e_machine = EM_X86_64,
1325 .regsets = x86_64_regsets, .n = ARRAY_SIZE(x86_64_regsets)
1326 };
1327
1328 #else /* CONFIG_X86_32 */
1329
1330 #define user_regs_struct32 user_regs_struct
1331 #define genregs32_get genregs_get
1332 #define genregs32_set genregs_set
1333
1334 #endif /* CONFIG_X86_64 */
1335
1336 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1337 static const struct user_regset x86_32_regsets[] = {
1338 [REGSET_GENERAL] = {
1339 .core_note_type = NT_PRSTATUS,
1340 .n = sizeof(struct user_regs_struct32) / sizeof(u32),
1341 .size = sizeof(u32), .align = sizeof(u32),
1342 .get = genregs32_get, .set = genregs32_set
1343 },
1344 [REGSET_FP] = {
1345 .core_note_type = NT_PRFPREG,
1346 .n = sizeof(struct user_i387_struct) / sizeof(u32),
1347 .size = sizeof(u32), .align = sizeof(u32),
1348 .active = fpregs_active, .get = fpregs_get, .set = fpregs_set
1349 },
1350 [REGSET_XFP] = {
1351 .core_note_type = NT_PRXFPREG,
1352 .n = sizeof(struct user_i387_struct) / sizeof(u32),
1353 .size = sizeof(u32), .align = sizeof(u32),
1354 .active = xfpregs_active, .get = xfpregs_get, .set = xfpregs_set
1355 },
1356 [REGSET_TLS] = {
1357 .core_note_type = NT_386_TLS,
1358 .n = GDT_ENTRY_TLS_ENTRIES, .bias = GDT_ENTRY_TLS_MIN,
1359 .size = sizeof(struct user_desc),
1360 .align = sizeof(struct user_desc),
1361 .active = regset_tls_active,
1362 .get = regset_tls_get, .set = regset_tls_set
1363 },
1364 };
1365
1366 static const struct user_regset_view user_x86_32_view = {
1367 .name = "i386", .e_machine = EM_386,
1368 .regsets = x86_32_regsets, .n = ARRAY_SIZE(x86_32_regsets)
1369 };
1370 #endif
1371
1372 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1373 {
1374 #ifdef CONFIG_IA32_EMULATION
1375 if (test_tsk_thread_flag(task, TIF_IA32))
1376 #endif
1377 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1378 return &user_x86_32_view;
1379 #endif
1380 #ifdef CONFIG_X86_64
1381 return &user_x86_64_view;
1382 #endif
1383 }
1384
1385 #ifdef CONFIG_X86_32
1386
1387 void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code)
1388 {
1389 struct siginfo info;
1390
1391 tsk->thread.trap_no = 1;
1392 tsk->thread.error_code = error_code;
1393
1394 memset(&info, 0, sizeof(info));
1395 info.si_signo = SIGTRAP;
1396 info.si_code = TRAP_BRKPT;
1397
1398 /* User-mode ip? */
1399 info.si_addr = user_mode_vm(regs) ? (void __user *) regs->ip : NULL;
1400
1401 /* Send us the fake SIGTRAP */
1402 force_sig_info(SIGTRAP, &info, tsk);
1403 }
1404
1405 /* notification of system call entry/exit
1406 * - triggered by current->work.syscall_trace
1407 */
1408 __attribute__((regparm(3)))
1409 int do_syscall_trace(struct pt_regs *regs, int entryexit)
1410 {
1411 int is_sysemu = test_thread_flag(TIF_SYSCALL_EMU);
1412 /*
1413 * With TIF_SYSCALL_EMU set we want to ignore TIF_SINGLESTEP for syscall
1414 * interception
1415 */
1416 int is_singlestep = !is_sysemu && test_thread_flag(TIF_SINGLESTEP);
1417 int ret = 0;
1418
1419 /* do the secure computing check first */
1420 if (!entryexit)
1421 secure_computing(regs->orig_ax);
1422
1423 if (unlikely(current->audit_context)) {
1424 if (entryexit)
1425 audit_syscall_exit(AUDITSC_RESULT(regs->ax),
1426 regs->ax);
1427 /* Debug traps, when using PTRACE_SINGLESTEP, must be sent only
1428 * on the syscall exit path. Normally, when TIF_SYSCALL_AUDIT is
1429 * not used, entry.S will call us only on syscall exit, not
1430 * entry; so when TIF_SYSCALL_AUDIT is used we must avoid
1431 * calling send_sigtrap() on syscall entry.
1432 *
1433 * Note that when PTRACE_SYSEMU_SINGLESTEP is used,
1434 * is_singlestep is false, despite his name, so we will still do
1435 * the correct thing.
1436 */
1437 else if (is_singlestep)
1438 goto out;
1439 }
1440
1441 if (!(current->ptrace & PT_PTRACED))
1442 goto out;
1443
1444 /* If a process stops on the 1st tracepoint with SYSCALL_TRACE
1445 * and then is resumed with SYSEMU_SINGLESTEP, it will come in
1446 * here. We have to check this and return */
1447 if (is_sysemu && entryexit)
1448 return 0;
1449
1450 /* Fake a debug trap */
1451 if (is_singlestep)
1452 send_sigtrap(current, regs, 0);
1453
1454 if (!test_thread_flag(TIF_SYSCALL_TRACE) && !is_sysemu)
1455 goto out;
1456
1457 /* the 0x80 provides a way for the tracing parent to distinguish
1458 between a syscall stop and SIGTRAP delivery */
1459 /* Note that the debugger could change the result of test_thread_flag!*/
1460 ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) ? 0x80:0));
1461
1462 /*
1463 * this isn't the same as continuing with a signal, but it will do
1464 * for normal use. strace only continues with a signal if the
1465 * stopping signal is not SIGTRAP. -brl
1466 */
1467 if (current->exit_code) {
1468 send_sig(current->exit_code, current, 1);
1469 current->exit_code = 0;
1470 }
1471 ret = is_sysemu;
1472 out:
1473 if (unlikely(current->audit_context) && !entryexit)
1474 audit_syscall_entry(AUDIT_ARCH_I386, regs->orig_ax,
1475 regs->bx, regs->cx, regs->dx, regs->si);
1476 if (ret == 0)
1477 return 0;
1478
1479 regs->orig_ax = -1; /* force skip of syscall restarting */
1480 if (unlikely(current->audit_context))
1481 audit_syscall_exit(AUDITSC_RESULT(regs->ax), regs->ax);
1482 return 1;
1483 }
1484
1485 #else /* CONFIG_X86_64 */
1486
1487 static void syscall_trace(struct pt_regs *regs)
1488 {
1489
1490 #if 0
1491 printk("trace %s ip %lx sp %lx ax %d origrax %d caller %lx tiflags %x ptrace %x\n",
1492 current->comm,
1493 regs->ip, regs->sp, regs->ax, regs->orig_ax, __builtin_return_address(0),
1494 current_thread_info()->flags, current->ptrace);
1495 #endif
1496
1497 ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
1498 ? 0x80 : 0));
1499 /*
1500 * this isn't the same as continuing with a signal, but it will do
1501 * for normal use. strace only continues with a signal if the
1502 * stopping signal is not SIGTRAP. -brl
1503 */
1504 if (current->exit_code) {
1505 send_sig(current->exit_code, current, 1);
1506 current->exit_code = 0;
1507 }
1508 }
1509
1510 asmlinkage void syscall_trace_enter(struct pt_regs *regs)
1511 {
1512 /* do the secure computing check first */
1513 secure_computing(regs->orig_ax);
1514
1515 if (test_thread_flag(TIF_SYSCALL_TRACE)
1516 && (current->ptrace & PT_PTRACED))
1517 syscall_trace(regs);
1518
1519 if (unlikely(current->audit_context)) {
1520 if (test_thread_flag(TIF_IA32)) {
1521 audit_syscall_entry(AUDIT_ARCH_I386,
1522 regs->orig_ax,
1523 regs->bx, regs->cx,
1524 regs->dx, regs->si);
1525 } else {
1526 audit_syscall_entry(AUDIT_ARCH_X86_64,
1527 regs->orig_ax,
1528 regs->di, regs->si,
1529 regs->dx, regs->r10);
1530 }
1531 }
1532 }
1533
1534 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
1535 {
1536 if (unlikely(current->audit_context))
1537 audit_syscall_exit(AUDITSC_RESULT(regs->ax), regs->ax);
1538
1539 if ((test_thread_flag(TIF_SYSCALL_TRACE)
1540 || test_thread_flag(TIF_SINGLESTEP))
1541 && (current->ptrace & PT_PTRACED))
1542 syscall_trace(regs);
1543 }
1544
1545 #endif /* CONFIG_X86_32 */
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