Loading...
1/* ptrace.c: Sparc process tracing support.
2 *
3 * Copyright (C) 1996, 2008 David S. Miller (davem@davemloft.net)
4 * Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
5 *
6 * Based upon code written by Ross Biro, Linus Torvalds, Bob Manson,
7 * and David Mosberger.
8 *
9 * Added Linux support -miguel (weird, eh?, the original code was meant
10 * to emulate SunOS).
11 */
12
13#include <linux/kernel.h>
14#include <linux/sched.h>
15#include <linux/mm.h>
16#include <linux/errno.h>
17#include <linux/ptrace.h>
18#include <linux/user.h>
19#include <linux/smp.h>
20#include <linux/security.h>
21#include <linux/seccomp.h>
22#include <linux/audit.h>
23#include <linux/signal.h>
24#include <linux/regset.h>
25#include <linux/tracehook.h>
26#include <trace/syscall.h>
27#include <linux/compat.h>
28#include <linux/elf.h>
29
30#include <asm/asi.h>
31#include <asm/pgtable.h>
32#include <asm/uaccess.h>
33#include <asm/psrcompat.h>
34#include <asm/visasm.h>
35#include <asm/spitfire.h>
36#include <asm/page.h>
37#include <asm/cpudata.h>
38#include <asm/cacheflush.h>
39
40#define CREATE_TRACE_POINTS
41#include <trace/events/syscalls.h>
42
43#include "entry.h"
44
45/* #define ALLOW_INIT_TRACING */
46
47/*
48 * Called by kernel/ptrace.c when detaching..
49 *
50 * Make sure single step bits etc are not set.
51 */
52void ptrace_disable(struct task_struct *child)
53{
54 /* nothing to do */
55}
56
57/* To get the necessary page struct, access_process_vm() first calls
58 * get_user_pages(). This has done a flush_dcache_page() on the
59 * accessed page. Then our caller (copy_{to,from}_user_page()) did
60 * to memcpy to read/write the data from that page.
61 *
62 * Now, the only thing we have to do is:
63 * 1) flush the D-cache if it's possible than an illegal alias
64 * has been created
65 * 2) flush the I-cache if this is pre-cheetah and we did a write
66 */
67void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
68 unsigned long uaddr, void *kaddr,
69 unsigned long len, int write)
70{
71 BUG_ON(len > PAGE_SIZE);
72
73 if (tlb_type == hypervisor)
74 return;
75
76 preempt_disable();
77
78#ifdef DCACHE_ALIASING_POSSIBLE
79 /* If bit 13 of the kernel address we used to access the
80 * user page is the same as the virtual address that page
81 * is mapped to in the user's address space, we can skip the
82 * D-cache flush.
83 */
84 if ((uaddr ^ (unsigned long) kaddr) & (1UL << 13)) {
85 unsigned long start = __pa(kaddr);
86 unsigned long end = start + len;
87 unsigned long dcache_line_size;
88
89 dcache_line_size = local_cpu_data().dcache_line_size;
90
91 if (tlb_type == spitfire) {
92 for (; start < end; start += dcache_line_size)
93 spitfire_put_dcache_tag(start & 0x3fe0, 0x0);
94 } else {
95 start &= ~(dcache_line_size - 1);
96 for (; start < end; start += dcache_line_size)
97 __asm__ __volatile__(
98 "stxa %%g0, [%0] %1\n\t"
99 "membar #Sync"
100 : /* no outputs */
101 : "r" (start),
102 "i" (ASI_DCACHE_INVALIDATE));
103 }
104 }
105#endif
106 if (write && tlb_type == spitfire) {
107 unsigned long start = (unsigned long) kaddr;
108 unsigned long end = start + len;
109 unsigned long icache_line_size;
110
111 icache_line_size = local_cpu_data().icache_line_size;
112
113 for (; start < end; start += icache_line_size)
114 flushi(start);
115 }
116
117 preempt_enable();
118}
119
120static int get_from_target(struct task_struct *target, unsigned long uaddr,
121 void *kbuf, int len)
122{
123 if (target == current) {
124 if (copy_from_user(kbuf, (void __user *) uaddr, len))
125 return -EFAULT;
126 } else {
127 int len2 = access_process_vm(target, uaddr, kbuf, len, 0);
128 if (len2 != len)
129 return -EFAULT;
130 }
131 return 0;
132}
133
134static int set_to_target(struct task_struct *target, unsigned long uaddr,
135 void *kbuf, int len)
136{
137 if (target == current) {
138 if (copy_to_user((void __user *) uaddr, kbuf, len))
139 return -EFAULT;
140 } else {
141 int len2 = access_process_vm(target, uaddr, kbuf, len, 1);
142 if (len2 != len)
143 return -EFAULT;
144 }
145 return 0;
146}
147
148static int regwindow64_get(struct task_struct *target,
149 const struct pt_regs *regs,
150 struct reg_window *wbuf)
151{
152 unsigned long rw_addr = regs->u_regs[UREG_I6];
153
154 if (test_tsk_thread_flag(current, TIF_32BIT)) {
155 struct reg_window32 win32;
156 int i;
157
158 if (get_from_target(target, rw_addr, &win32, sizeof(win32)))
159 return -EFAULT;
160 for (i = 0; i < 8; i++)
161 wbuf->locals[i] = win32.locals[i];
162 for (i = 0; i < 8; i++)
163 wbuf->ins[i] = win32.ins[i];
164 } else {
165 rw_addr += STACK_BIAS;
166 if (get_from_target(target, rw_addr, wbuf, sizeof(*wbuf)))
167 return -EFAULT;
168 }
169
170 return 0;
171}
172
173static int regwindow64_set(struct task_struct *target,
174 const struct pt_regs *regs,
175 struct reg_window *wbuf)
176{
177 unsigned long rw_addr = regs->u_regs[UREG_I6];
178
179 if (test_tsk_thread_flag(current, TIF_32BIT)) {
180 struct reg_window32 win32;
181 int i;
182
183 for (i = 0; i < 8; i++)
184 win32.locals[i] = wbuf->locals[i];
185 for (i = 0; i < 8; i++)
186 win32.ins[i] = wbuf->ins[i];
187
188 if (set_to_target(target, rw_addr, &win32, sizeof(win32)))
189 return -EFAULT;
190 } else {
191 rw_addr += STACK_BIAS;
192 if (set_to_target(target, rw_addr, wbuf, sizeof(*wbuf)))
193 return -EFAULT;
194 }
195
196 return 0;
197}
198
199enum sparc_regset {
200 REGSET_GENERAL,
201 REGSET_FP,
202};
203
204static int genregs64_get(struct task_struct *target,
205 const struct user_regset *regset,
206 unsigned int pos, unsigned int count,
207 void *kbuf, void __user *ubuf)
208{
209 const struct pt_regs *regs = task_pt_regs(target);
210 int ret;
211
212 if (target == current)
213 flushw_user();
214
215 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
216 regs->u_regs,
217 0, 16 * sizeof(u64));
218 if (!ret && count && pos < (32 * sizeof(u64))) {
219 struct reg_window window;
220
221 if (regwindow64_get(target, regs, &window))
222 return -EFAULT;
223 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
224 &window,
225 16 * sizeof(u64),
226 32 * sizeof(u64));
227 }
228
229 if (!ret) {
230 /* TSTATE, TPC, TNPC */
231 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
232 ®s->tstate,
233 32 * sizeof(u64),
234 35 * sizeof(u64));
235 }
236
237 if (!ret) {
238 unsigned long y = regs->y;
239
240 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
241 &y,
242 35 * sizeof(u64),
243 36 * sizeof(u64));
244 }
245
246 if (!ret) {
247 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
248 36 * sizeof(u64), -1);
249
250 }
251 return ret;
252}
253
254static int genregs64_set(struct task_struct *target,
255 const struct user_regset *regset,
256 unsigned int pos, unsigned int count,
257 const void *kbuf, const void __user *ubuf)
258{
259 struct pt_regs *regs = task_pt_regs(target);
260 int ret;
261
262 if (target == current)
263 flushw_user();
264
265 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
266 regs->u_regs,
267 0, 16 * sizeof(u64));
268 if (!ret && count && pos < (32 * sizeof(u64))) {
269 struct reg_window window;
270
271 if (regwindow64_get(target, regs, &window))
272 return -EFAULT;
273
274 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
275 &window,
276 16 * sizeof(u64),
277 32 * sizeof(u64));
278
279 if (!ret &&
280 regwindow64_set(target, regs, &window))
281 return -EFAULT;
282 }
283
284 if (!ret && count > 0) {
285 unsigned long tstate;
286
287 /* TSTATE */
288 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
289 &tstate,
290 32 * sizeof(u64),
291 33 * sizeof(u64));
292 if (!ret) {
293 /* Only the condition codes and the "in syscall"
294 * state can be modified in the %tstate register.
295 */
296 tstate &= (TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
297 regs->tstate &= ~(TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
298 regs->tstate |= tstate;
299 }
300 }
301
302 if (!ret) {
303 /* TPC, TNPC */
304 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
305 ®s->tpc,
306 33 * sizeof(u64),
307 35 * sizeof(u64));
308 }
309
310 if (!ret) {
311 unsigned long y;
312
313 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
314 &y,
315 35 * sizeof(u64),
316 36 * sizeof(u64));
317 if (!ret)
318 regs->y = y;
319 }
320
321 if (!ret)
322 ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
323 36 * sizeof(u64), -1);
324
325 return ret;
326}
327
328static int fpregs64_get(struct task_struct *target,
329 const struct user_regset *regset,
330 unsigned int pos, unsigned int count,
331 void *kbuf, void __user *ubuf)
332{
333 const unsigned long *fpregs = task_thread_info(target)->fpregs;
334 unsigned long fprs, fsr, gsr;
335 int ret;
336
337 if (target == current)
338 save_and_clear_fpu();
339
340 fprs = task_thread_info(target)->fpsaved[0];
341
342 if (fprs & FPRS_DL)
343 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
344 fpregs,
345 0, 16 * sizeof(u64));
346 else
347 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
348 0,
349 16 * sizeof(u64));
350
351 if (!ret) {
352 if (fprs & FPRS_DU)
353 ret = user_regset_copyout(&pos, &count,
354 &kbuf, &ubuf,
355 fpregs + 16,
356 16 * sizeof(u64),
357 32 * sizeof(u64));
358 else
359 ret = user_regset_copyout_zero(&pos, &count,
360 &kbuf, &ubuf,
361 16 * sizeof(u64),
362 32 * sizeof(u64));
363 }
364
365 if (fprs & FPRS_FEF) {
366 fsr = task_thread_info(target)->xfsr[0];
367 gsr = task_thread_info(target)->gsr[0];
368 } else {
369 fsr = gsr = 0;
370 }
371
372 if (!ret)
373 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
374 &fsr,
375 32 * sizeof(u64),
376 33 * sizeof(u64));
377 if (!ret)
378 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
379 &gsr,
380 33 * sizeof(u64),
381 34 * sizeof(u64));
382 if (!ret)
383 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
384 &fprs,
385 34 * sizeof(u64),
386 35 * sizeof(u64));
387
388 if (!ret)
389 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
390 35 * sizeof(u64), -1);
391
392 return ret;
393}
394
395static int fpregs64_set(struct task_struct *target,
396 const struct user_regset *regset,
397 unsigned int pos, unsigned int count,
398 const void *kbuf, const void __user *ubuf)
399{
400 unsigned long *fpregs = task_thread_info(target)->fpregs;
401 unsigned long fprs;
402 int ret;
403
404 if (target == current)
405 save_and_clear_fpu();
406
407 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
408 fpregs,
409 0, 32 * sizeof(u64));
410 if (!ret)
411 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
412 task_thread_info(target)->xfsr,
413 32 * sizeof(u64),
414 33 * sizeof(u64));
415 if (!ret)
416 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
417 task_thread_info(target)->gsr,
418 33 * sizeof(u64),
419 34 * sizeof(u64));
420
421 fprs = task_thread_info(target)->fpsaved[0];
422 if (!ret && count > 0) {
423 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
424 &fprs,
425 34 * sizeof(u64),
426 35 * sizeof(u64));
427 }
428
429 fprs |= (FPRS_FEF | FPRS_DL | FPRS_DU);
430 task_thread_info(target)->fpsaved[0] = fprs;
431
432 if (!ret)
433 ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
434 35 * sizeof(u64), -1);
435 return ret;
436}
437
438static const struct user_regset sparc64_regsets[] = {
439 /* Format is:
440 * G0 --> G7
441 * O0 --> O7
442 * L0 --> L7
443 * I0 --> I7
444 * TSTATE, TPC, TNPC, Y
445 */
446 [REGSET_GENERAL] = {
447 .core_note_type = NT_PRSTATUS,
448 .n = 36,
449 .size = sizeof(u64), .align = sizeof(u64),
450 .get = genregs64_get, .set = genregs64_set
451 },
452 /* Format is:
453 * F0 --> F63
454 * FSR
455 * GSR
456 * FPRS
457 */
458 [REGSET_FP] = {
459 .core_note_type = NT_PRFPREG,
460 .n = 35,
461 .size = sizeof(u64), .align = sizeof(u64),
462 .get = fpregs64_get, .set = fpregs64_set
463 },
464};
465
466static const struct user_regset_view user_sparc64_view = {
467 .name = "sparc64", .e_machine = EM_SPARCV9,
468 .regsets = sparc64_regsets, .n = ARRAY_SIZE(sparc64_regsets)
469};
470
471#ifdef CONFIG_COMPAT
472static int genregs32_get(struct task_struct *target,
473 const struct user_regset *regset,
474 unsigned int pos, unsigned int count,
475 void *kbuf, void __user *ubuf)
476{
477 const struct pt_regs *regs = task_pt_regs(target);
478 compat_ulong_t __user *reg_window;
479 compat_ulong_t *k = kbuf;
480 compat_ulong_t __user *u = ubuf;
481 compat_ulong_t reg;
482
483 if (target == current)
484 flushw_user();
485
486 pos /= sizeof(reg);
487 count /= sizeof(reg);
488
489 if (kbuf) {
490 for (; count > 0 && pos < 16; count--)
491 *k++ = regs->u_regs[pos++];
492
493 reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
494 reg_window -= 16;
495 if (target == current) {
496 for (; count > 0 && pos < 32; count--) {
497 if (get_user(*k++, ®_window[pos++]))
498 return -EFAULT;
499 }
500 } else {
501 for (; count > 0 && pos < 32; count--) {
502 if (access_process_vm(target,
503 (unsigned long)
504 ®_window[pos],
505 k, sizeof(*k), 0)
506 != sizeof(*k))
507 return -EFAULT;
508 k++;
509 pos++;
510 }
511 }
512 } else {
513 for (; count > 0 && pos < 16; count--) {
514 if (put_user((compat_ulong_t) regs->u_regs[pos++], u++))
515 return -EFAULT;
516 }
517
518 reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
519 reg_window -= 16;
520 if (target == current) {
521 for (; count > 0 && pos < 32; count--) {
522 if (get_user(reg, ®_window[pos++]) ||
523 put_user(reg, u++))
524 return -EFAULT;
525 }
526 } else {
527 for (; count > 0 && pos < 32; count--) {
528 if (access_process_vm(target,
529 (unsigned long)
530 ®_window[pos],
531 ®, sizeof(reg), 0)
532 != sizeof(reg))
533 return -EFAULT;
534 if (access_process_vm(target,
535 (unsigned long) u,
536 ®, sizeof(reg), 1)
537 != sizeof(reg))
538 return -EFAULT;
539 pos++;
540 u++;
541 }
542 }
543 }
544 while (count > 0) {
545 switch (pos) {
546 case 32: /* PSR */
547 reg = tstate_to_psr(regs->tstate);
548 break;
549 case 33: /* PC */
550 reg = regs->tpc;
551 break;
552 case 34: /* NPC */
553 reg = regs->tnpc;
554 break;
555 case 35: /* Y */
556 reg = regs->y;
557 break;
558 case 36: /* WIM */
559 case 37: /* TBR */
560 reg = 0;
561 break;
562 default:
563 goto finish;
564 }
565
566 if (kbuf)
567 *k++ = reg;
568 else if (put_user(reg, u++))
569 return -EFAULT;
570 pos++;
571 count--;
572 }
573finish:
574 pos *= sizeof(reg);
575 count *= sizeof(reg);
576
577 return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
578 38 * sizeof(reg), -1);
579}
580
581static int genregs32_set(struct task_struct *target,
582 const struct user_regset *regset,
583 unsigned int pos, unsigned int count,
584 const void *kbuf, const void __user *ubuf)
585{
586 struct pt_regs *regs = task_pt_regs(target);
587 compat_ulong_t __user *reg_window;
588 const compat_ulong_t *k = kbuf;
589 const compat_ulong_t __user *u = ubuf;
590 compat_ulong_t reg;
591
592 if (target == current)
593 flushw_user();
594
595 pos /= sizeof(reg);
596 count /= sizeof(reg);
597
598 if (kbuf) {
599 for (; count > 0 && pos < 16; count--)
600 regs->u_regs[pos++] = *k++;
601
602 reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
603 reg_window -= 16;
604 if (target == current) {
605 for (; count > 0 && pos < 32; count--) {
606 if (put_user(*k++, ®_window[pos++]))
607 return -EFAULT;
608 }
609 } else {
610 for (; count > 0 && pos < 32; count--) {
611 if (access_process_vm(target,
612 (unsigned long)
613 ®_window[pos],
614 (void *) k,
615 sizeof(*k), 1)
616 != sizeof(*k))
617 return -EFAULT;
618 k++;
619 pos++;
620 }
621 }
622 } else {
623 for (; count > 0 && pos < 16; count--) {
624 if (get_user(reg, u++))
625 return -EFAULT;
626 regs->u_regs[pos++] = reg;
627 }
628
629 reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
630 reg_window -= 16;
631 if (target == current) {
632 for (; count > 0 && pos < 32; count--) {
633 if (get_user(reg, u++) ||
634 put_user(reg, ®_window[pos++]))
635 return -EFAULT;
636 }
637 } else {
638 for (; count > 0 && pos < 32; count--) {
639 if (access_process_vm(target,
640 (unsigned long)
641 u,
642 ®, sizeof(reg), 0)
643 != sizeof(reg))
644 return -EFAULT;
645 if (access_process_vm(target,
646 (unsigned long)
647 ®_window[pos],
648 ®, sizeof(reg), 1)
649 != sizeof(reg))
650 return -EFAULT;
651 pos++;
652 u++;
653 }
654 }
655 }
656 while (count > 0) {
657 unsigned long tstate;
658
659 if (kbuf)
660 reg = *k++;
661 else if (get_user(reg, u++))
662 return -EFAULT;
663
664 switch (pos) {
665 case 32: /* PSR */
666 tstate = regs->tstate;
667 tstate &= ~(TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
668 tstate |= psr_to_tstate_icc(reg);
669 if (reg & PSR_SYSCALL)
670 tstate |= TSTATE_SYSCALL;
671 regs->tstate = tstate;
672 break;
673 case 33: /* PC */
674 regs->tpc = reg;
675 break;
676 case 34: /* NPC */
677 regs->tnpc = reg;
678 break;
679 case 35: /* Y */
680 regs->y = reg;
681 break;
682 case 36: /* WIM */
683 case 37: /* TBR */
684 break;
685 default:
686 goto finish;
687 }
688
689 pos++;
690 count--;
691 }
692finish:
693 pos *= sizeof(reg);
694 count *= sizeof(reg);
695
696 return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
697 38 * sizeof(reg), -1);
698}
699
700static int fpregs32_get(struct task_struct *target,
701 const struct user_regset *regset,
702 unsigned int pos, unsigned int count,
703 void *kbuf, void __user *ubuf)
704{
705 const unsigned long *fpregs = task_thread_info(target)->fpregs;
706 compat_ulong_t enabled;
707 unsigned long fprs;
708 compat_ulong_t fsr;
709 int ret = 0;
710
711 if (target == current)
712 save_and_clear_fpu();
713
714 fprs = task_thread_info(target)->fpsaved[0];
715 if (fprs & FPRS_FEF) {
716 fsr = task_thread_info(target)->xfsr[0];
717 enabled = 1;
718 } else {
719 fsr = 0;
720 enabled = 0;
721 }
722
723 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
724 fpregs,
725 0, 32 * sizeof(u32));
726
727 if (!ret)
728 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
729 32 * sizeof(u32),
730 33 * sizeof(u32));
731 if (!ret)
732 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
733 &fsr,
734 33 * sizeof(u32),
735 34 * sizeof(u32));
736
737 if (!ret) {
738 compat_ulong_t val;
739
740 val = (enabled << 8) | (8 << 16);
741 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
742 &val,
743 34 * sizeof(u32),
744 35 * sizeof(u32));
745 }
746
747 if (!ret)
748 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
749 35 * sizeof(u32), -1);
750
751 return ret;
752}
753
754static int fpregs32_set(struct task_struct *target,
755 const struct user_regset *regset,
756 unsigned int pos, unsigned int count,
757 const void *kbuf, const void __user *ubuf)
758{
759 unsigned long *fpregs = task_thread_info(target)->fpregs;
760 unsigned long fprs;
761 int ret;
762
763 if (target == current)
764 save_and_clear_fpu();
765
766 fprs = task_thread_info(target)->fpsaved[0];
767
768 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
769 fpregs,
770 0, 32 * sizeof(u32));
771 if (!ret)
772 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
773 32 * sizeof(u32),
774 33 * sizeof(u32));
775 if (!ret && count > 0) {
776 compat_ulong_t fsr;
777 unsigned long val;
778
779 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
780 &fsr,
781 33 * sizeof(u32),
782 34 * sizeof(u32));
783 if (!ret) {
784 val = task_thread_info(target)->xfsr[0];
785 val &= 0xffffffff00000000UL;
786 val |= fsr;
787 task_thread_info(target)->xfsr[0] = val;
788 }
789 }
790
791 fprs |= (FPRS_FEF | FPRS_DL);
792 task_thread_info(target)->fpsaved[0] = fprs;
793
794 if (!ret)
795 ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
796 34 * sizeof(u32), -1);
797 return ret;
798}
799
800static const struct user_regset sparc32_regsets[] = {
801 /* Format is:
802 * G0 --> G7
803 * O0 --> O7
804 * L0 --> L7
805 * I0 --> I7
806 * PSR, PC, nPC, Y, WIM, TBR
807 */
808 [REGSET_GENERAL] = {
809 .core_note_type = NT_PRSTATUS,
810 .n = 38,
811 .size = sizeof(u32), .align = sizeof(u32),
812 .get = genregs32_get, .set = genregs32_set
813 },
814 /* Format is:
815 * F0 --> F31
816 * empty 32-bit word
817 * FSR (32--bit word)
818 * FPU QUEUE COUNT (8-bit char)
819 * FPU QUEUE ENTRYSIZE (8-bit char)
820 * FPU ENABLED (8-bit char)
821 * empty 8-bit char
822 * FPU QUEUE (64 32-bit ints)
823 */
824 [REGSET_FP] = {
825 .core_note_type = NT_PRFPREG,
826 .n = 99,
827 .size = sizeof(u32), .align = sizeof(u32),
828 .get = fpregs32_get, .set = fpregs32_set
829 },
830};
831
832static const struct user_regset_view user_sparc32_view = {
833 .name = "sparc", .e_machine = EM_SPARC,
834 .regsets = sparc32_regsets, .n = ARRAY_SIZE(sparc32_regsets)
835};
836#endif /* CONFIG_COMPAT */
837
838const struct user_regset_view *task_user_regset_view(struct task_struct *task)
839{
840#ifdef CONFIG_COMPAT
841 if (test_tsk_thread_flag(task, TIF_32BIT))
842 return &user_sparc32_view;
843#endif
844 return &user_sparc64_view;
845}
846
847#ifdef CONFIG_COMPAT
848struct compat_fps {
849 unsigned int regs[32];
850 unsigned int fsr;
851 unsigned int flags;
852 unsigned int extra;
853 unsigned int fpqd;
854 struct compat_fq {
855 unsigned int insnaddr;
856 unsigned int insn;
857 } fpq[16];
858};
859
860long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
861 compat_ulong_t caddr, compat_ulong_t cdata)
862{
863 const struct user_regset_view *view = task_user_regset_view(current);
864 compat_ulong_t caddr2 = task_pt_regs(current)->u_regs[UREG_I4];
865 struct pt_regs32 __user *pregs;
866 struct compat_fps __user *fps;
867 unsigned long addr2 = caddr2;
868 unsigned long addr = caddr;
869 unsigned long data = cdata;
870 int ret;
871
872 pregs = (struct pt_regs32 __user *) addr;
873 fps = (struct compat_fps __user *) addr;
874
875 switch (request) {
876 case PTRACE_PEEKUSR:
877 ret = (addr != 0) ? -EIO : 0;
878 break;
879
880 case PTRACE_GETREGS:
881 ret = copy_regset_to_user(child, view, REGSET_GENERAL,
882 32 * sizeof(u32),
883 4 * sizeof(u32),
884 &pregs->psr);
885 if (!ret)
886 ret = copy_regset_to_user(child, view, REGSET_GENERAL,
887 1 * sizeof(u32),
888 15 * sizeof(u32),
889 &pregs->u_regs[0]);
890 break;
891
892 case PTRACE_SETREGS:
893 ret = copy_regset_from_user(child, view, REGSET_GENERAL,
894 32 * sizeof(u32),
895 4 * sizeof(u32),
896 &pregs->psr);
897 if (!ret)
898 ret = copy_regset_from_user(child, view, REGSET_GENERAL,
899 1 * sizeof(u32),
900 15 * sizeof(u32),
901 &pregs->u_regs[0]);
902 break;
903
904 case PTRACE_GETFPREGS:
905 ret = copy_regset_to_user(child, view, REGSET_FP,
906 0 * sizeof(u32),
907 32 * sizeof(u32),
908 &fps->regs[0]);
909 if (!ret)
910 ret = copy_regset_to_user(child, view, REGSET_FP,
911 33 * sizeof(u32),
912 1 * sizeof(u32),
913 &fps->fsr);
914 if (!ret) {
915 if (__put_user(0, &fps->flags) ||
916 __put_user(0, &fps->extra) ||
917 __put_user(0, &fps->fpqd) ||
918 clear_user(&fps->fpq[0], 32 * sizeof(unsigned int)))
919 ret = -EFAULT;
920 }
921 break;
922
923 case PTRACE_SETFPREGS:
924 ret = copy_regset_from_user(child, view, REGSET_FP,
925 0 * sizeof(u32),
926 32 * sizeof(u32),
927 &fps->regs[0]);
928 if (!ret)
929 ret = copy_regset_from_user(child, view, REGSET_FP,
930 33 * sizeof(u32),
931 1 * sizeof(u32),
932 &fps->fsr);
933 break;
934
935 case PTRACE_READTEXT:
936 case PTRACE_READDATA:
937 ret = ptrace_readdata(child, addr,
938 (char __user *)addr2, data);
939 if (ret == data)
940 ret = 0;
941 else if (ret >= 0)
942 ret = -EIO;
943 break;
944
945 case PTRACE_WRITETEXT:
946 case PTRACE_WRITEDATA:
947 ret = ptrace_writedata(child, (char __user *) addr2,
948 addr, data);
949 if (ret == data)
950 ret = 0;
951 else if (ret >= 0)
952 ret = -EIO;
953 break;
954
955 default:
956 if (request == PTRACE_SPARC_DETACH)
957 request = PTRACE_DETACH;
958 ret = compat_ptrace_request(child, request, addr, data);
959 break;
960 }
961
962 return ret;
963}
964#endif /* CONFIG_COMPAT */
965
966struct fps {
967 unsigned int regs[64];
968 unsigned long fsr;
969};
970
971long arch_ptrace(struct task_struct *child, long request,
972 unsigned long addr, unsigned long data)
973{
974 const struct user_regset_view *view = task_user_regset_view(current);
975 unsigned long addr2 = task_pt_regs(current)->u_regs[UREG_I4];
976 struct pt_regs __user *pregs;
977 struct fps __user *fps;
978 void __user *addr2p;
979 int ret;
980
981 pregs = (struct pt_regs __user *) addr;
982 fps = (struct fps __user *) addr;
983 addr2p = (void __user *) addr2;
984
985 switch (request) {
986 case PTRACE_PEEKUSR:
987 ret = (addr != 0) ? -EIO : 0;
988 break;
989
990 case PTRACE_GETREGS64:
991 ret = copy_regset_to_user(child, view, REGSET_GENERAL,
992 1 * sizeof(u64),
993 15 * sizeof(u64),
994 &pregs->u_regs[0]);
995 if (!ret) {
996 /* XXX doesn't handle 'y' register correctly XXX */
997 ret = copy_regset_to_user(child, view, REGSET_GENERAL,
998 32 * sizeof(u64),
999 4 * sizeof(u64),
1000 &pregs->tstate);
1001 }
1002 break;
1003
1004 case PTRACE_SETREGS64:
1005 ret = copy_regset_from_user(child, view, REGSET_GENERAL,
1006 1 * sizeof(u64),
1007 15 * sizeof(u64),
1008 &pregs->u_regs[0]);
1009 if (!ret) {
1010 /* XXX doesn't handle 'y' register correctly XXX */
1011 ret = copy_regset_from_user(child, view, REGSET_GENERAL,
1012 32 * sizeof(u64),
1013 4 * sizeof(u64),
1014 &pregs->tstate);
1015 }
1016 break;
1017
1018 case PTRACE_GETFPREGS64:
1019 ret = copy_regset_to_user(child, view, REGSET_FP,
1020 0 * sizeof(u64),
1021 33 * sizeof(u64),
1022 fps);
1023 break;
1024
1025 case PTRACE_SETFPREGS64:
1026 ret = copy_regset_from_user(child, view, REGSET_FP,
1027 0 * sizeof(u64),
1028 33 * sizeof(u64),
1029 fps);
1030 break;
1031
1032 case PTRACE_READTEXT:
1033 case PTRACE_READDATA:
1034 ret = ptrace_readdata(child, addr, addr2p, data);
1035 if (ret == data)
1036 ret = 0;
1037 else if (ret >= 0)
1038 ret = -EIO;
1039 break;
1040
1041 case PTRACE_WRITETEXT:
1042 case PTRACE_WRITEDATA:
1043 ret = ptrace_writedata(child, addr2p, addr, data);
1044 if (ret == data)
1045 ret = 0;
1046 else if (ret >= 0)
1047 ret = -EIO;
1048 break;
1049
1050 default:
1051 if (request == PTRACE_SPARC_DETACH)
1052 request = PTRACE_DETACH;
1053 ret = ptrace_request(child, request, addr, data);
1054 break;
1055 }
1056
1057 return ret;
1058}
1059
1060asmlinkage int syscall_trace_enter(struct pt_regs *regs)
1061{
1062 int ret = 0;
1063
1064 /* do the secure computing check first */
1065 secure_computing_strict(regs->u_regs[UREG_G1]);
1066
1067 if (test_thread_flag(TIF_SYSCALL_TRACE))
1068 ret = tracehook_report_syscall_entry(regs);
1069
1070 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1071 trace_sys_enter(regs, regs->u_regs[UREG_G1]);
1072
1073 audit_syscall_entry((test_thread_flag(TIF_32BIT) ?
1074 AUDIT_ARCH_SPARC :
1075 AUDIT_ARCH_SPARC64),
1076 regs->u_regs[UREG_G1],
1077 regs->u_regs[UREG_I0],
1078 regs->u_regs[UREG_I1],
1079 regs->u_regs[UREG_I2],
1080 regs->u_regs[UREG_I3]);
1081
1082 return ret;
1083}
1084
1085asmlinkage void syscall_trace_leave(struct pt_regs *regs)
1086{
1087 audit_syscall_exit(regs);
1088
1089 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1090 trace_sys_exit(regs, regs->u_regs[UREG_G1]);
1091
1092 if (test_thread_flag(TIF_SYSCALL_TRACE))
1093 tracehook_report_syscall_exit(regs, 0);
1094}
1/* ptrace.c: Sparc process tracing support.
2 *
3 * Copyright (C) 1996, 2008 David S. Miller (davem@davemloft.net)
4 * Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
5 *
6 * Based upon code written by Ross Biro, Linus Torvalds, Bob Manson,
7 * and David Mosberger.
8 *
9 * Added Linux support -miguel (weird, eh?, the original code was meant
10 * to emulate SunOS).
11 */
12
13#include <linux/kernel.h>
14#include <linux/sched.h>
15#include <linux/sched/task_stack.h>
16#include <linux/mm.h>
17#include <linux/errno.h>
18#include <linux/export.h>
19#include <linux/ptrace.h>
20#include <linux/user.h>
21#include <linux/smp.h>
22#include <linux/security.h>
23#include <linux/seccomp.h>
24#include <linux/audit.h>
25#include <linux/signal.h>
26#include <linux/regset.h>
27#include <linux/tracehook.h>
28#include <trace/syscall.h>
29#include <linux/compat.h>
30#include <linux/elf.h>
31#include <linux/context_tracking.h>
32
33#include <asm/asi.h>
34#include <asm/pgtable.h>
35#include <linux/uaccess.h>
36#include <asm/psrcompat.h>
37#include <asm/visasm.h>
38#include <asm/spitfire.h>
39#include <asm/page.h>
40#include <asm/cpudata.h>
41#include <asm/cacheflush.h>
42
43#define CREATE_TRACE_POINTS
44#include <trace/events/syscalls.h>
45
46#include "entry.h"
47
48/* #define ALLOW_INIT_TRACING */
49
50struct pt_regs_offset {
51 const char *name;
52 int offset;
53};
54
55#define REG_OFFSET_NAME(n, r) \
56 {.name = n, .offset = (PT_V9_##r)}
57#define REG_OFFSET_END {.name = NULL, .offset = 0}
58
59static const struct pt_regs_offset regoffset_table[] = {
60 REG_OFFSET_NAME("g0", G0),
61 REG_OFFSET_NAME("g1", G1),
62 REG_OFFSET_NAME("g2", G2),
63 REG_OFFSET_NAME("g3", G3),
64 REG_OFFSET_NAME("g4", G4),
65 REG_OFFSET_NAME("g5", G5),
66 REG_OFFSET_NAME("g6", G6),
67 REG_OFFSET_NAME("g7", G7),
68
69 REG_OFFSET_NAME("i0", I0),
70 REG_OFFSET_NAME("i1", I1),
71 REG_OFFSET_NAME("i2", I2),
72 REG_OFFSET_NAME("i3", I3),
73 REG_OFFSET_NAME("i4", I4),
74 REG_OFFSET_NAME("i5", I5),
75 REG_OFFSET_NAME("i6", I6),
76 REG_OFFSET_NAME("i7", I7),
77
78 REG_OFFSET_NAME("tstate", TSTATE),
79 REG_OFFSET_NAME("pc", TPC),
80 REG_OFFSET_NAME("npc", TNPC),
81 REG_OFFSET_NAME("y", Y),
82 REG_OFFSET_NAME("lr", I7),
83
84 REG_OFFSET_END,
85};
86
87/*
88 * Called by kernel/ptrace.c when detaching..
89 *
90 * Make sure single step bits etc are not set.
91 */
92void ptrace_disable(struct task_struct *child)
93{
94 /* nothing to do */
95}
96
97/* To get the necessary page struct, access_process_vm() first calls
98 * get_user_pages(). This has done a flush_dcache_page() on the
99 * accessed page. Then our caller (copy_{to,from}_user_page()) did
100 * to memcpy to read/write the data from that page.
101 *
102 * Now, the only thing we have to do is:
103 * 1) flush the D-cache if it's possible than an illegal alias
104 * has been created
105 * 2) flush the I-cache if this is pre-cheetah and we did a write
106 */
107void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
108 unsigned long uaddr, void *kaddr,
109 unsigned long len, int write)
110{
111 BUG_ON(len > PAGE_SIZE);
112
113 if (tlb_type == hypervisor)
114 return;
115
116 preempt_disable();
117
118#ifdef DCACHE_ALIASING_POSSIBLE
119 /* If bit 13 of the kernel address we used to access the
120 * user page is the same as the virtual address that page
121 * is mapped to in the user's address space, we can skip the
122 * D-cache flush.
123 */
124 if ((uaddr ^ (unsigned long) kaddr) & (1UL << 13)) {
125 unsigned long start = __pa(kaddr);
126 unsigned long end = start + len;
127 unsigned long dcache_line_size;
128
129 dcache_line_size = local_cpu_data().dcache_line_size;
130
131 if (tlb_type == spitfire) {
132 for (; start < end; start += dcache_line_size)
133 spitfire_put_dcache_tag(start & 0x3fe0, 0x0);
134 } else {
135 start &= ~(dcache_line_size - 1);
136 for (; start < end; start += dcache_line_size)
137 __asm__ __volatile__(
138 "stxa %%g0, [%0] %1\n\t"
139 "membar #Sync"
140 : /* no outputs */
141 : "r" (start),
142 "i" (ASI_DCACHE_INVALIDATE));
143 }
144 }
145#endif
146 if (write && tlb_type == spitfire) {
147 unsigned long start = (unsigned long) kaddr;
148 unsigned long end = start + len;
149 unsigned long icache_line_size;
150
151 icache_line_size = local_cpu_data().icache_line_size;
152
153 for (; start < end; start += icache_line_size)
154 flushi(start);
155 }
156
157 preempt_enable();
158}
159EXPORT_SYMBOL_GPL(flush_ptrace_access);
160
161static int get_from_target(struct task_struct *target, unsigned long uaddr,
162 void *kbuf, int len)
163{
164 if (target == current) {
165 if (copy_from_user(kbuf, (void __user *) uaddr, len))
166 return -EFAULT;
167 } else {
168 int len2 = access_process_vm(target, uaddr, kbuf, len,
169 FOLL_FORCE);
170 if (len2 != len)
171 return -EFAULT;
172 }
173 return 0;
174}
175
176static int set_to_target(struct task_struct *target, unsigned long uaddr,
177 void *kbuf, int len)
178{
179 if (target == current) {
180 if (copy_to_user((void __user *) uaddr, kbuf, len))
181 return -EFAULT;
182 } else {
183 int len2 = access_process_vm(target, uaddr, kbuf, len,
184 FOLL_FORCE | FOLL_WRITE);
185 if (len2 != len)
186 return -EFAULT;
187 }
188 return 0;
189}
190
191static int regwindow64_get(struct task_struct *target,
192 const struct pt_regs *regs,
193 struct reg_window *wbuf)
194{
195 unsigned long rw_addr = regs->u_regs[UREG_I6];
196
197 if (!test_thread_64bit_stack(rw_addr)) {
198 struct reg_window32 win32;
199 int i;
200
201 if (get_from_target(target, rw_addr, &win32, sizeof(win32)))
202 return -EFAULT;
203 for (i = 0; i < 8; i++)
204 wbuf->locals[i] = win32.locals[i];
205 for (i = 0; i < 8; i++)
206 wbuf->ins[i] = win32.ins[i];
207 } else {
208 rw_addr += STACK_BIAS;
209 if (get_from_target(target, rw_addr, wbuf, sizeof(*wbuf)))
210 return -EFAULT;
211 }
212
213 return 0;
214}
215
216static int regwindow64_set(struct task_struct *target,
217 const struct pt_regs *regs,
218 struct reg_window *wbuf)
219{
220 unsigned long rw_addr = regs->u_regs[UREG_I6];
221
222 if (!test_thread_64bit_stack(rw_addr)) {
223 struct reg_window32 win32;
224 int i;
225
226 for (i = 0; i < 8; i++)
227 win32.locals[i] = wbuf->locals[i];
228 for (i = 0; i < 8; i++)
229 win32.ins[i] = wbuf->ins[i];
230
231 if (set_to_target(target, rw_addr, &win32, sizeof(win32)))
232 return -EFAULT;
233 } else {
234 rw_addr += STACK_BIAS;
235 if (set_to_target(target, rw_addr, wbuf, sizeof(*wbuf)))
236 return -EFAULT;
237 }
238
239 return 0;
240}
241
242enum sparc_regset {
243 REGSET_GENERAL,
244 REGSET_FP,
245};
246
247static int genregs64_get(struct task_struct *target,
248 const struct user_regset *regset,
249 unsigned int pos, unsigned int count,
250 void *kbuf, void __user *ubuf)
251{
252 const struct pt_regs *regs = task_pt_regs(target);
253 int ret;
254
255 if (target == current)
256 flushw_user();
257
258 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
259 regs->u_regs,
260 0, 16 * sizeof(u64));
261 if (!ret && count && pos < (32 * sizeof(u64))) {
262 struct reg_window window;
263
264 if (regwindow64_get(target, regs, &window))
265 return -EFAULT;
266 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
267 &window,
268 16 * sizeof(u64),
269 32 * sizeof(u64));
270 }
271
272 if (!ret) {
273 /* TSTATE, TPC, TNPC */
274 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
275 ®s->tstate,
276 32 * sizeof(u64),
277 35 * sizeof(u64));
278 }
279
280 if (!ret) {
281 unsigned long y = regs->y;
282
283 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
284 &y,
285 35 * sizeof(u64),
286 36 * sizeof(u64));
287 }
288
289 if (!ret) {
290 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
291 36 * sizeof(u64), -1);
292
293 }
294 return ret;
295}
296
297static int genregs64_set(struct task_struct *target,
298 const struct user_regset *regset,
299 unsigned int pos, unsigned int count,
300 const void *kbuf, const void __user *ubuf)
301{
302 struct pt_regs *regs = task_pt_regs(target);
303 int ret;
304
305 if (target == current)
306 flushw_user();
307
308 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
309 regs->u_regs,
310 0, 16 * sizeof(u64));
311 if (!ret && count && pos < (32 * sizeof(u64))) {
312 struct reg_window window;
313
314 if (regwindow64_get(target, regs, &window))
315 return -EFAULT;
316
317 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
318 &window,
319 16 * sizeof(u64),
320 32 * sizeof(u64));
321
322 if (!ret &&
323 regwindow64_set(target, regs, &window))
324 return -EFAULT;
325 }
326
327 if (!ret && count > 0) {
328 unsigned long tstate;
329
330 /* TSTATE */
331 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
332 &tstate,
333 32 * sizeof(u64),
334 33 * sizeof(u64));
335 if (!ret) {
336 /* Only the condition codes and the "in syscall"
337 * state can be modified in the %tstate register.
338 */
339 tstate &= (TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
340 regs->tstate &= ~(TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
341 regs->tstate |= tstate;
342 }
343 }
344
345 if (!ret) {
346 /* TPC, TNPC */
347 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
348 ®s->tpc,
349 33 * sizeof(u64),
350 35 * sizeof(u64));
351 }
352
353 if (!ret) {
354 unsigned long y = regs->y;
355
356 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
357 &y,
358 35 * sizeof(u64),
359 36 * sizeof(u64));
360 if (!ret)
361 regs->y = y;
362 }
363
364 if (!ret)
365 ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
366 36 * sizeof(u64), -1);
367
368 return ret;
369}
370
371static int fpregs64_get(struct task_struct *target,
372 const struct user_regset *regset,
373 unsigned int pos, unsigned int count,
374 void *kbuf, void __user *ubuf)
375{
376 const unsigned long *fpregs = task_thread_info(target)->fpregs;
377 unsigned long fprs, fsr, gsr;
378 int ret;
379
380 if (target == current)
381 save_and_clear_fpu();
382
383 fprs = task_thread_info(target)->fpsaved[0];
384
385 if (fprs & FPRS_DL)
386 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
387 fpregs,
388 0, 16 * sizeof(u64));
389 else
390 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
391 0,
392 16 * sizeof(u64));
393
394 if (!ret) {
395 if (fprs & FPRS_DU)
396 ret = user_regset_copyout(&pos, &count,
397 &kbuf, &ubuf,
398 fpregs + 16,
399 16 * sizeof(u64),
400 32 * sizeof(u64));
401 else
402 ret = user_regset_copyout_zero(&pos, &count,
403 &kbuf, &ubuf,
404 16 * sizeof(u64),
405 32 * sizeof(u64));
406 }
407
408 if (fprs & FPRS_FEF) {
409 fsr = task_thread_info(target)->xfsr[0];
410 gsr = task_thread_info(target)->gsr[0];
411 } else {
412 fsr = gsr = 0;
413 }
414
415 if (!ret)
416 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
417 &fsr,
418 32 * sizeof(u64),
419 33 * sizeof(u64));
420 if (!ret)
421 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
422 &gsr,
423 33 * sizeof(u64),
424 34 * sizeof(u64));
425 if (!ret)
426 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
427 &fprs,
428 34 * sizeof(u64),
429 35 * sizeof(u64));
430
431 if (!ret)
432 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
433 35 * sizeof(u64), -1);
434
435 return ret;
436}
437
438static int fpregs64_set(struct task_struct *target,
439 const struct user_regset *regset,
440 unsigned int pos, unsigned int count,
441 const void *kbuf, const void __user *ubuf)
442{
443 unsigned long *fpregs = task_thread_info(target)->fpregs;
444 unsigned long fprs;
445 int ret;
446
447 if (target == current)
448 save_and_clear_fpu();
449
450 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
451 fpregs,
452 0, 32 * sizeof(u64));
453 if (!ret)
454 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
455 task_thread_info(target)->xfsr,
456 32 * sizeof(u64),
457 33 * sizeof(u64));
458 if (!ret)
459 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
460 task_thread_info(target)->gsr,
461 33 * sizeof(u64),
462 34 * sizeof(u64));
463
464 fprs = task_thread_info(target)->fpsaved[0];
465 if (!ret && count > 0) {
466 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
467 &fprs,
468 34 * sizeof(u64),
469 35 * sizeof(u64));
470 }
471
472 fprs |= (FPRS_FEF | FPRS_DL | FPRS_DU);
473 task_thread_info(target)->fpsaved[0] = fprs;
474
475 if (!ret)
476 ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
477 35 * sizeof(u64), -1);
478 return ret;
479}
480
481static const struct user_regset sparc64_regsets[] = {
482 /* Format is:
483 * G0 --> G7
484 * O0 --> O7
485 * L0 --> L7
486 * I0 --> I7
487 * TSTATE, TPC, TNPC, Y
488 */
489 [REGSET_GENERAL] = {
490 .core_note_type = NT_PRSTATUS,
491 .n = 36,
492 .size = sizeof(u64), .align = sizeof(u64),
493 .get = genregs64_get, .set = genregs64_set
494 },
495 /* Format is:
496 * F0 --> F63
497 * FSR
498 * GSR
499 * FPRS
500 */
501 [REGSET_FP] = {
502 .core_note_type = NT_PRFPREG,
503 .n = 35,
504 .size = sizeof(u64), .align = sizeof(u64),
505 .get = fpregs64_get, .set = fpregs64_set
506 },
507};
508
509static const struct user_regset_view user_sparc64_view = {
510 .name = "sparc64", .e_machine = EM_SPARCV9,
511 .regsets = sparc64_regsets, .n = ARRAY_SIZE(sparc64_regsets)
512};
513
514#ifdef CONFIG_COMPAT
515static int genregs32_get(struct task_struct *target,
516 const struct user_regset *regset,
517 unsigned int pos, unsigned int count,
518 void *kbuf, void __user *ubuf)
519{
520 const struct pt_regs *regs = task_pt_regs(target);
521 compat_ulong_t __user *reg_window;
522 compat_ulong_t *k = kbuf;
523 compat_ulong_t __user *u = ubuf;
524 compat_ulong_t reg;
525
526 if (target == current)
527 flushw_user();
528
529 pos /= sizeof(reg);
530 count /= sizeof(reg);
531
532 if (kbuf) {
533 for (; count > 0 && pos < 16; count--)
534 *k++ = regs->u_regs[pos++];
535
536 reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
537 reg_window -= 16;
538 if (target == current) {
539 for (; count > 0 && pos < 32; count--) {
540 if (get_user(*k++, ®_window[pos++]))
541 return -EFAULT;
542 }
543 } else {
544 for (; count > 0 && pos < 32; count--) {
545 if (access_process_vm(target,
546 (unsigned long)
547 ®_window[pos],
548 k, sizeof(*k),
549 FOLL_FORCE)
550 != sizeof(*k))
551 return -EFAULT;
552 k++;
553 pos++;
554 }
555 }
556 } else {
557 for (; count > 0 && pos < 16; count--) {
558 if (put_user((compat_ulong_t) regs->u_regs[pos++], u++))
559 return -EFAULT;
560 }
561
562 reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
563 reg_window -= 16;
564 if (target == current) {
565 for (; count > 0 && pos < 32; count--) {
566 if (get_user(reg, ®_window[pos++]) ||
567 put_user(reg, u++))
568 return -EFAULT;
569 }
570 } else {
571 for (; count > 0 && pos < 32; count--) {
572 if (access_process_vm(target,
573 (unsigned long)
574 ®_window[pos],
575 ®, sizeof(reg),
576 FOLL_FORCE)
577 != sizeof(reg))
578 return -EFAULT;
579 if (access_process_vm(target,
580 (unsigned long) u,
581 ®, sizeof(reg),
582 FOLL_FORCE | FOLL_WRITE)
583 != sizeof(reg))
584 return -EFAULT;
585 pos++;
586 u++;
587 }
588 }
589 }
590 while (count > 0) {
591 switch (pos) {
592 case 32: /* PSR */
593 reg = tstate_to_psr(regs->tstate);
594 break;
595 case 33: /* PC */
596 reg = regs->tpc;
597 break;
598 case 34: /* NPC */
599 reg = regs->tnpc;
600 break;
601 case 35: /* Y */
602 reg = regs->y;
603 break;
604 case 36: /* WIM */
605 case 37: /* TBR */
606 reg = 0;
607 break;
608 default:
609 goto finish;
610 }
611
612 if (kbuf)
613 *k++ = reg;
614 else if (put_user(reg, u++))
615 return -EFAULT;
616 pos++;
617 count--;
618 }
619finish:
620 pos *= sizeof(reg);
621 count *= sizeof(reg);
622
623 return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
624 38 * sizeof(reg), -1);
625}
626
627static int genregs32_set(struct task_struct *target,
628 const struct user_regset *regset,
629 unsigned int pos, unsigned int count,
630 const void *kbuf, const void __user *ubuf)
631{
632 struct pt_regs *regs = task_pt_regs(target);
633 compat_ulong_t __user *reg_window;
634 const compat_ulong_t *k = kbuf;
635 const compat_ulong_t __user *u = ubuf;
636 compat_ulong_t reg;
637
638 if (target == current)
639 flushw_user();
640
641 pos /= sizeof(reg);
642 count /= sizeof(reg);
643
644 if (kbuf) {
645 for (; count > 0 && pos < 16; count--)
646 regs->u_regs[pos++] = *k++;
647
648 reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
649 reg_window -= 16;
650 if (target == current) {
651 for (; count > 0 && pos < 32; count--) {
652 if (put_user(*k++, ®_window[pos++]))
653 return -EFAULT;
654 }
655 } else {
656 for (; count > 0 && pos < 32; count--) {
657 if (access_process_vm(target,
658 (unsigned long)
659 ®_window[pos],
660 (void *) k,
661 sizeof(*k),
662 FOLL_FORCE | FOLL_WRITE)
663 != sizeof(*k))
664 return -EFAULT;
665 k++;
666 pos++;
667 }
668 }
669 } else {
670 for (; count > 0 && pos < 16; count--) {
671 if (get_user(reg, u++))
672 return -EFAULT;
673 regs->u_regs[pos++] = reg;
674 }
675
676 reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
677 reg_window -= 16;
678 if (target == current) {
679 for (; count > 0 && pos < 32; count--) {
680 if (get_user(reg, u++) ||
681 put_user(reg, ®_window[pos++]))
682 return -EFAULT;
683 }
684 } else {
685 for (; count > 0 && pos < 32; count--) {
686 if (access_process_vm(target,
687 (unsigned long)
688 u,
689 ®, sizeof(reg),
690 FOLL_FORCE)
691 != sizeof(reg))
692 return -EFAULT;
693 if (access_process_vm(target,
694 (unsigned long)
695 ®_window[pos],
696 ®, sizeof(reg),
697 FOLL_FORCE | FOLL_WRITE)
698 != sizeof(reg))
699 return -EFAULT;
700 pos++;
701 u++;
702 }
703 }
704 }
705 while (count > 0) {
706 unsigned long tstate;
707
708 if (kbuf)
709 reg = *k++;
710 else if (get_user(reg, u++))
711 return -EFAULT;
712
713 switch (pos) {
714 case 32: /* PSR */
715 tstate = regs->tstate;
716 tstate &= ~(TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
717 tstate |= psr_to_tstate_icc(reg);
718 if (reg & PSR_SYSCALL)
719 tstate |= TSTATE_SYSCALL;
720 regs->tstate = tstate;
721 break;
722 case 33: /* PC */
723 regs->tpc = reg;
724 break;
725 case 34: /* NPC */
726 regs->tnpc = reg;
727 break;
728 case 35: /* Y */
729 regs->y = reg;
730 break;
731 case 36: /* WIM */
732 case 37: /* TBR */
733 break;
734 default:
735 goto finish;
736 }
737
738 pos++;
739 count--;
740 }
741finish:
742 pos *= sizeof(reg);
743 count *= sizeof(reg);
744
745 return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
746 38 * sizeof(reg), -1);
747}
748
749static int fpregs32_get(struct task_struct *target,
750 const struct user_regset *regset,
751 unsigned int pos, unsigned int count,
752 void *kbuf, void __user *ubuf)
753{
754 const unsigned long *fpregs = task_thread_info(target)->fpregs;
755 compat_ulong_t enabled;
756 unsigned long fprs;
757 compat_ulong_t fsr;
758 int ret = 0;
759
760 if (target == current)
761 save_and_clear_fpu();
762
763 fprs = task_thread_info(target)->fpsaved[0];
764 if (fprs & FPRS_FEF) {
765 fsr = task_thread_info(target)->xfsr[0];
766 enabled = 1;
767 } else {
768 fsr = 0;
769 enabled = 0;
770 }
771
772 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
773 fpregs,
774 0, 32 * sizeof(u32));
775
776 if (!ret)
777 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
778 32 * sizeof(u32),
779 33 * sizeof(u32));
780 if (!ret)
781 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
782 &fsr,
783 33 * sizeof(u32),
784 34 * sizeof(u32));
785
786 if (!ret) {
787 compat_ulong_t val;
788
789 val = (enabled << 8) | (8 << 16);
790 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
791 &val,
792 34 * sizeof(u32),
793 35 * sizeof(u32));
794 }
795
796 if (!ret)
797 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
798 35 * sizeof(u32), -1);
799
800 return ret;
801}
802
803static int fpregs32_set(struct task_struct *target,
804 const struct user_regset *regset,
805 unsigned int pos, unsigned int count,
806 const void *kbuf, const void __user *ubuf)
807{
808 unsigned long *fpregs = task_thread_info(target)->fpregs;
809 unsigned long fprs;
810 int ret;
811
812 if (target == current)
813 save_and_clear_fpu();
814
815 fprs = task_thread_info(target)->fpsaved[0];
816
817 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
818 fpregs,
819 0, 32 * sizeof(u32));
820 if (!ret)
821 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
822 32 * sizeof(u32),
823 33 * sizeof(u32));
824 if (!ret && count > 0) {
825 compat_ulong_t fsr;
826 unsigned long val;
827
828 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
829 &fsr,
830 33 * sizeof(u32),
831 34 * sizeof(u32));
832 if (!ret) {
833 val = task_thread_info(target)->xfsr[0];
834 val &= 0xffffffff00000000UL;
835 val |= fsr;
836 task_thread_info(target)->xfsr[0] = val;
837 }
838 }
839
840 fprs |= (FPRS_FEF | FPRS_DL);
841 task_thread_info(target)->fpsaved[0] = fprs;
842
843 if (!ret)
844 ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
845 34 * sizeof(u32), -1);
846 return ret;
847}
848
849static const struct user_regset sparc32_regsets[] = {
850 /* Format is:
851 * G0 --> G7
852 * O0 --> O7
853 * L0 --> L7
854 * I0 --> I7
855 * PSR, PC, nPC, Y, WIM, TBR
856 */
857 [REGSET_GENERAL] = {
858 .core_note_type = NT_PRSTATUS,
859 .n = 38,
860 .size = sizeof(u32), .align = sizeof(u32),
861 .get = genregs32_get, .set = genregs32_set
862 },
863 /* Format is:
864 * F0 --> F31
865 * empty 32-bit word
866 * FSR (32--bit word)
867 * FPU QUEUE COUNT (8-bit char)
868 * FPU QUEUE ENTRYSIZE (8-bit char)
869 * FPU ENABLED (8-bit char)
870 * empty 8-bit char
871 * FPU QUEUE (64 32-bit ints)
872 */
873 [REGSET_FP] = {
874 .core_note_type = NT_PRFPREG,
875 .n = 99,
876 .size = sizeof(u32), .align = sizeof(u32),
877 .get = fpregs32_get, .set = fpregs32_set
878 },
879};
880
881static const struct user_regset_view user_sparc32_view = {
882 .name = "sparc", .e_machine = EM_SPARC,
883 .regsets = sparc32_regsets, .n = ARRAY_SIZE(sparc32_regsets)
884};
885#endif /* CONFIG_COMPAT */
886
887const struct user_regset_view *task_user_regset_view(struct task_struct *task)
888{
889#ifdef CONFIG_COMPAT
890 if (test_tsk_thread_flag(task, TIF_32BIT))
891 return &user_sparc32_view;
892#endif
893 return &user_sparc64_view;
894}
895
896#ifdef CONFIG_COMPAT
897struct compat_fps {
898 unsigned int regs[32];
899 unsigned int fsr;
900 unsigned int flags;
901 unsigned int extra;
902 unsigned int fpqd;
903 struct compat_fq {
904 unsigned int insnaddr;
905 unsigned int insn;
906 } fpq[16];
907};
908
909long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
910 compat_ulong_t caddr, compat_ulong_t cdata)
911{
912 const struct user_regset_view *view = task_user_regset_view(current);
913 compat_ulong_t caddr2 = task_pt_regs(current)->u_regs[UREG_I4];
914 struct pt_regs32 __user *pregs;
915 struct compat_fps __user *fps;
916 unsigned long addr2 = caddr2;
917 unsigned long addr = caddr;
918 unsigned long data = cdata;
919 int ret;
920
921 pregs = (struct pt_regs32 __user *) addr;
922 fps = (struct compat_fps __user *) addr;
923
924 switch (request) {
925 case PTRACE_PEEKUSR:
926 ret = (addr != 0) ? -EIO : 0;
927 break;
928
929 case PTRACE_GETREGS:
930 ret = copy_regset_to_user(child, view, REGSET_GENERAL,
931 32 * sizeof(u32),
932 4 * sizeof(u32),
933 &pregs->psr);
934 if (!ret)
935 ret = copy_regset_to_user(child, view, REGSET_GENERAL,
936 1 * sizeof(u32),
937 15 * sizeof(u32),
938 &pregs->u_regs[0]);
939 break;
940
941 case PTRACE_SETREGS:
942 ret = copy_regset_from_user(child, view, REGSET_GENERAL,
943 32 * sizeof(u32),
944 4 * sizeof(u32),
945 &pregs->psr);
946 if (!ret)
947 ret = copy_regset_from_user(child, view, REGSET_GENERAL,
948 1 * sizeof(u32),
949 15 * sizeof(u32),
950 &pregs->u_regs[0]);
951 break;
952
953 case PTRACE_GETFPREGS:
954 ret = copy_regset_to_user(child, view, REGSET_FP,
955 0 * sizeof(u32),
956 32 * sizeof(u32),
957 &fps->regs[0]);
958 if (!ret)
959 ret = copy_regset_to_user(child, view, REGSET_FP,
960 33 * sizeof(u32),
961 1 * sizeof(u32),
962 &fps->fsr);
963 if (!ret) {
964 if (__put_user(0, &fps->flags) ||
965 __put_user(0, &fps->extra) ||
966 __put_user(0, &fps->fpqd) ||
967 clear_user(&fps->fpq[0], 32 * sizeof(unsigned int)))
968 ret = -EFAULT;
969 }
970 break;
971
972 case PTRACE_SETFPREGS:
973 ret = copy_regset_from_user(child, view, REGSET_FP,
974 0 * sizeof(u32),
975 32 * sizeof(u32),
976 &fps->regs[0]);
977 if (!ret)
978 ret = copy_regset_from_user(child, view, REGSET_FP,
979 33 * sizeof(u32),
980 1 * sizeof(u32),
981 &fps->fsr);
982 break;
983
984 case PTRACE_READTEXT:
985 case PTRACE_READDATA:
986 ret = ptrace_readdata(child, addr,
987 (char __user *)addr2, data);
988 if (ret == data)
989 ret = 0;
990 else if (ret >= 0)
991 ret = -EIO;
992 break;
993
994 case PTRACE_WRITETEXT:
995 case PTRACE_WRITEDATA:
996 ret = ptrace_writedata(child, (char __user *) addr2,
997 addr, data);
998 if (ret == data)
999 ret = 0;
1000 else if (ret >= 0)
1001 ret = -EIO;
1002 break;
1003
1004 default:
1005 if (request == PTRACE_SPARC_DETACH)
1006 request = PTRACE_DETACH;
1007 ret = compat_ptrace_request(child, request, addr, data);
1008 break;
1009 }
1010
1011 return ret;
1012}
1013#endif /* CONFIG_COMPAT */
1014
1015struct fps {
1016 unsigned int regs[64];
1017 unsigned long fsr;
1018};
1019
1020long arch_ptrace(struct task_struct *child, long request,
1021 unsigned long addr, unsigned long data)
1022{
1023 const struct user_regset_view *view = task_user_regset_view(current);
1024 unsigned long addr2 = task_pt_regs(current)->u_regs[UREG_I4];
1025 struct pt_regs __user *pregs;
1026 struct fps __user *fps;
1027 void __user *addr2p;
1028 int ret;
1029
1030 pregs = (struct pt_regs __user *) addr;
1031 fps = (struct fps __user *) addr;
1032 addr2p = (void __user *) addr2;
1033
1034 switch (request) {
1035 case PTRACE_PEEKUSR:
1036 ret = (addr != 0) ? -EIO : 0;
1037 break;
1038
1039 case PTRACE_GETREGS64:
1040 ret = copy_regset_to_user(child, view, REGSET_GENERAL,
1041 1 * sizeof(u64),
1042 15 * sizeof(u64),
1043 &pregs->u_regs[0]);
1044 if (!ret) {
1045 /* XXX doesn't handle 'y' register correctly XXX */
1046 ret = copy_regset_to_user(child, view, REGSET_GENERAL,
1047 32 * sizeof(u64),
1048 4 * sizeof(u64),
1049 &pregs->tstate);
1050 }
1051 break;
1052
1053 case PTRACE_SETREGS64:
1054 ret = copy_regset_from_user(child, view, REGSET_GENERAL,
1055 1 * sizeof(u64),
1056 15 * sizeof(u64),
1057 &pregs->u_regs[0]);
1058 if (!ret) {
1059 /* XXX doesn't handle 'y' register correctly XXX */
1060 ret = copy_regset_from_user(child, view, REGSET_GENERAL,
1061 32 * sizeof(u64),
1062 4 * sizeof(u64),
1063 &pregs->tstate);
1064 }
1065 break;
1066
1067 case PTRACE_GETFPREGS64:
1068 ret = copy_regset_to_user(child, view, REGSET_FP,
1069 0 * sizeof(u64),
1070 33 * sizeof(u64),
1071 fps);
1072 break;
1073
1074 case PTRACE_SETFPREGS64:
1075 ret = copy_regset_from_user(child, view, REGSET_FP,
1076 0 * sizeof(u64),
1077 33 * sizeof(u64),
1078 fps);
1079 break;
1080
1081 case PTRACE_READTEXT:
1082 case PTRACE_READDATA:
1083 ret = ptrace_readdata(child, addr, addr2p, data);
1084 if (ret == data)
1085 ret = 0;
1086 else if (ret >= 0)
1087 ret = -EIO;
1088 break;
1089
1090 case PTRACE_WRITETEXT:
1091 case PTRACE_WRITEDATA:
1092 ret = ptrace_writedata(child, addr2p, addr, data);
1093 if (ret == data)
1094 ret = 0;
1095 else if (ret >= 0)
1096 ret = -EIO;
1097 break;
1098
1099 default:
1100 if (request == PTRACE_SPARC_DETACH)
1101 request = PTRACE_DETACH;
1102 ret = ptrace_request(child, request, addr, data);
1103 break;
1104 }
1105
1106 return ret;
1107}
1108
1109asmlinkage int syscall_trace_enter(struct pt_regs *regs)
1110{
1111 int ret = 0;
1112
1113 /* do the secure computing check first */
1114 secure_computing_strict(regs->u_regs[UREG_G1]);
1115
1116 if (test_thread_flag(TIF_NOHZ))
1117 user_exit();
1118
1119 if (test_thread_flag(TIF_SYSCALL_TRACE))
1120 ret = tracehook_report_syscall_entry(regs);
1121
1122 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1123 trace_sys_enter(regs, regs->u_regs[UREG_G1]);
1124
1125 audit_syscall_entry(regs->u_regs[UREG_G1], regs->u_regs[UREG_I0],
1126 regs->u_regs[UREG_I1], regs->u_regs[UREG_I2],
1127 regs->u_regs[UREG_I3]);
1128
1129 return ret;
1130}
1131
1132asmlinkage void syscall_trace_leave(struct pt_regs *regs)
1133{
1134 if (test_thread_flag(TIF_NOHZ))
1135 user_exit();
1136
1137 audit_syscall_exit(regs);
1138
1139 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1140 trace_sys_exit(regs, regs->u_regs[UREG_I0]);
1141
1142 if (test_thread_flag(TIF_SYSCALL_TRACE))
1143 tracehook_report_syscall_exit(regs, 0);
1144
1145 if (test_thread_flag(TIF_NOHZ))
1146 user_enter();
1147}
1148
1149/**
1150 * regs_query_register_offset() - query register offset from its name
1151 * @name: the name of a register
1152 *
1153 * regs_query_register_offset() returns the offset of a register in struct
1154 * pt_regs from its name. If the name is invalid, this returns -EINVAL;
1155 */
1156int regs_query_register_offset(const char *name)
1157{
1158 const struct pt_regs_offset *roff;
1159
1160 for (roff = regoffset_table; roff->name != NULL; roff++)
1161 if (!strcmp(roff->name, name))
1162 return roff->offset;
1163 return -EINVAL;
1164}
1165
1166/**
1167 * regs_within_kernel_stack() - check the address in the stack
1168 * @regs: pt_regs which contains kernel stack pointer.
1169 * @addr: address which is checked.
1170 *
1171 * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
1172 * If @addr is within the kernel stack, it returns true. If not, returns false.
1173 */
1174static inline int regs_within_kernel_stack(struct pt_regs *regs,
1175 unsigned long addr)
1176{
1177 unsigned long ksp = kernel_stack_pointer(regs) + STACK_BIAS;
1178 return ((addr & ~(THREAD_SIZE - 1)) ==
1179 (ksp & ~(THREAD_SIZE - 1)));
1180}
1181
1182/**
1183 * regs_get_kernel_stack_nth() - get Nth entry of the stack
1184 * @regs: pt_regs which contains kernel stack pointer.
1185 * @n: stack entry number.
1186 *
1187 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1188 * is specified by @regs. If the @n th entry is NOT in the kernel stack,
1189 * this returns 0.
1190 */
1191unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1192{
1193 unsigned long ksp = kernel_stack_pointer(regs) + STACK_BIAS;
1194 unsigned long *addr = (unsigned long *)ksp;
1195 addr += n;
1196 if (regs_within_kernel_stack(regs, (unsigned long)addr))
1197 return *addr;
1198 else
1199 return 0;
1200}