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// SPDX-License-Identifier: GPL-2.0-only
2/* ptrace.c: Sparc process tracing support.
3 *
4 * Copyright (C) 1996, 2008 David S. Miller (davem@davemloft.net)
5 * Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
6 *
7 * Based upon code written by Ross Biro, Linus Torvalds, Bob Manson,
8 * and David Mosberger.
9 *
10 * Added Linux support -miguel (weird, eh?, the original code was meant
11 * to emulate SunOS).
12 */
13
14#include <linux/kernel.h>
15#include <linux/sched.h>
16#include <linux/sched/task_stack.h>
17#include <linux/mm.h>
18#include <linux/errno.h>
19#include <linux/export.h>
20#include <linux/ptrace.h>
21#include <linux/user.h>
22#include <linux/smp.h>
23#include <linux/security.h>
24#include <linux/seccomp.h>
25#include <linux/audit.h>
26#include <linux/signal.h>
27#include <linux/regset.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 <linux/uaccess.h>
35#include <asm/psrcompat.h>
36#include <asm/visasm.h>
37#include <asm/spitfire.h>
38#include <asm/page.h>
39#include <asm/cpudata.h>
40#include <asm/cacheflush.h>
41
42#define CREATE_TRACE_POINTS
43#include <trace/events/syscalls.h>
44
45#include "entry.h"
46
47/* #define ALLOW_INIT_TRACING */
48
49struct pt_regs_offset {
50 const char *name;
51 int offset;
52};
53
54#define REG_OFFSET_NAME(n, r) \
55 {.name = n, .offset = (PT_V9_##r)}
56#define REG_OFFSET_END {.name = NULL, .offset = 0}
57
58static const struct pt_regs_offset regoffset_table[] = {
59 REG_OFFSET_NAME("g0", G0),
60 REG_OFFSET_NAME("g1", G1),
61 REG_OFFSET_NAME("g2", G2),
62 REG_OFFSET_NAME("g3", G3),
63 REG_OFFSET_NAME("g4", G4),
64 REG_OFFSET_NAME("g5", G5),
65 REG_OFFSET_NAME("g6", G6),
66 REG_OFFSET_NAME("g7", G7),
67
68 REG_OFFSET_NAME("i0", I0),
69 REG_OFFSET_NAME("i1", I1),
70 REG_OFFSET_NAME("i2", I2),
71 REG_OFFSET_NAME("i3", I3),
72 REG_OFFSET_NAME("i4", I4),
73 REG_OFFSET_NAME("i5", I5),
74 REG_OFFSET_NAME("i6", I6),
75 REG_OFFSET_NAME("i7", I7),
76
77 REG_OFFSET_NAME("tstate", TSTATE),
78 REG_OFFSET_NAME("pc", TPC),
79 REG_OFFSET_NAME("npc", TNPC),
80 REG_OFFSET_NAME("y", Y),
81 REG_OFFSET_NAME("lr", I7),
82
83 REG_OFFSET_END,
84};
85
86/*
87 * Called by kernel/ptrace.c when detaching..
88 *
89 * Make sure single step bits etc are not set.
90 */
91void ptrace_disable(struct task_struct *child)
92{
93 /* nothing to do */
94}
95
96/* To get the necessary page struct, access_process_vm() first calls
97 * get_user_pages(). This has done a flush_dcache_page() on the
98 * accessed page. Then our caller (copy_{to,from}_user_page()) did
99 * to memcpy to read/write the data from that page.
100 *
101 * Now, the only thing we have to do is:
102 * 1) flush the D-cache if it's possible than an illegal alias
103 * has been created
104 * 2) flush the I-cache if this is pre-cheetah and we did a write
105 */
106void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
107 unsigned long uaddr, void *kaddr,
108 unsigned long len, int write)
109{
110 BUG_ON(len > PAGE_SIZE);
111
112 if (tlb_type == hypervisor)
113 return;
114
115 preempt_disable();
116
117#ifdef DCACHE_ALIASING_POSSIBLE
118 /* If bit 13 of the kernel address we used to access the
119 * user page is the same as the virtual address that page
120 * is mapped to in the user's address space, we can skip the
121 * D-cache flush.
122 */
123 if ((uaddr ^ (unsigned long) kaddr) & (1UL << 13)) {
124 unsigned long start = __pa(kaddr);
125 unsigned long end = start + len;
126 unsigned long dcache_line_size;
127
128 dcache_line_size = local_cpu_data().dcache_line_size;
129
130 if (tlb_type == spitfire) {
131 for (; start < end; start += dcache_line_size)
132 spitfire_put_dcache_tag(start & 0x3fe0, 0x0);
133 } else {
134 start &= ~(dcache_line_size - 1);
135 for (; start < end; start += dcache_line_size)
136 __asm__ __volatile__(
137 "stxa %%g0, [%0] %1\n\t"
138 "membar #Sync"
139 : /* no outputs */
140 : "r" (start),
141 "i" (ASI_DCACHE_INVALIDATE));
142 }
143 }
144#endif
145 if (write && tlb_type == spitfire) {
146 unsigned long start = (unsigned long) kaddr;
147 unsigned long end = start + len;
148 unsigned long icache_line_size;
149
150 icache_line_size = local_cpu_data().icache_line_size;
151
152 for (; start < end; start += icache_line_size)
153 flushi(start);
154 }
155
156 preempt_enable();
157}
158EXPORT_SYMBOL_GPL(flush_ptrace_access);
159
160static int get_from_target(struct task_struct *target, unsigned long uaddr,
161 void *kbuf, int len)
162{
163 if (target == current) {
164 if (copy_from_user(kbuf, (void __user *) uaddr, len))
165 return -EFAULT;
166 } else {
167 int len2 = access_process_vm(target, uaddr, kbuf, len,
168 FOLL_FORCE);
169 if (len2 != len)
170 return -EFAULT;
171 }
172 return 0;
173}
174
175static int set_to_target(struct task_struct *target, unsigned long uaddr,
176 void *kbuf, int len)
177{
178 if (target == current) {
179 if (copy_to_user((void __user *) uaddr, kbuf, len))
180 return -EFAULT;
181 } else {
182 int len2 = access_process_vm(target, uaddr, kbuf, len,
183 FOLL_FORCE | FOLL_WRITE);
184 if (len2 != len)
185 return -EFAULT;
186 }
187 return 0;
188}
189
190static int regwindow64_get(struct task_struct *target,
191 const struct pt_regs *regs,
192 struct reg_window *wbuf)
193{
194 unsigned long rw_addr = regs->u_regs[UREG_I6];
195
196 if (!test_thread_64bit_stack(rw_addr)) {
197 struct reg_window32 win32;
198 int i;
199
200 if (get_from_target(target, rw_addr, &win32, sizeof(win32)))
201 return -EFAULT;
202 for (i = 0; i < 8; i++)
203 wbuf->locals[i] = win32.locals[i];
204 for (i = 0; i < 8; i++)
205 wbuf->ins[i] = win32.ins[i];
206 } else {
207 rw_addr += STACK_BIAS;
208 if (get_from_target(target, rw_addr, wbuf, sizeof(*wbuf)))
209 return -EFAULT;
210 }
211
212 return 0;
213}
214
215static int regwindow64_set(struct task_struct *target,
216 const struct pt_regs *regs,
217 struct reg_window *wbuf)
218{
219 unsigned long rw_addr = regs->u_regs[UREG_I6];
220
221 if (!test_thread_64bit_stack(rw_addr)) {
222 struct reg_window32 win32;
223 int i;
224
225 for (i = 0; i < 8; i++)
226 win32.locals[i] = wbuf->locals[i];
227 for (i = 0; i < 8; i++)
228 win32.ins[i] = wbuf->ins[i];
229
230 if (set_to_target(target, rw_addr, &win32, sizeof(win32)))
231 return -EFAULT;
232 } else {
233 rw_addr += STACK_BIAS;
234 if (set_to_target(target, rw_addr, wbuf, sizeof(*wbuf)))
235 return -EFAULT;
236 }
237
238 return 0;
239}
240
241enum sparc_regset {
242 REGSET_GENERAL,
243 REGSET_FP,
244};
245
246static int genregs64_get(struct task_struct *target,
247 const struct user_regset *regset,
248 struct membuf to)
249{
250 const struct pt_regs *regs = task_pt_regs(target);
251 struct reg_window window;
252
253 if (target == current)
254 flushw_user();
255
256 membuf_write(&to, regs->u_regs, 16 * sizeof(u64));
257 if (!to.left)
258 return 0;
259 if (regwindow64_get(target, regs, &window))
260 return -EFAULT;
261 membuf_write(&to, &window, 16 * sizeof(u64));
262 /* TSTATE, TPC, TNPC */
263 membuf_write(&to, ®s->tstate, 3 * sizeof(u64));
264 return membuf_store(&to, (u64)regs->y);
265}
266
267static int genregs64_set(struct task_struct *target,
268 const struct user_regset *regset,
269 unsigned int pos, unsigned int count,
270 const void *kbuf, const void __user *ubuf)
271{
272 struct pt_regs *regs = task_pt_regs(target);
273 int ret;
274
275 if (target == current)
276 flushw_user();
277
278 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
279 regs->u_regs,
280 0, 16 * sizeof(u64));
281 if (!ret && count && pos < (32 * sizeof(u64))) {
282 struct reg_window window;
283
284 if (regwindow64_get(target, regs, &window))
285 return -EFAULT;
286
287 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
288 &window,
289 16 * sizeof(u64),
290 32 * sizeof(u64));
291
292 if (!ret &&
293 regwindow64_set(target, regs, &window))
294 return -EFAULT;
295 }
296
297 if (!ret && count > 0) {
298 unsigned long tstate;
299
300 /* TSTATE */
301 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
302 &tstate,
303 32 * sizeof(u64),
304 33 * sizeof(u64));
305 if (!ret) {
306 /* Only the condition codes and the "in syscall"
307 * state can be modified in the %tstate register.
308 */
309 tstate &= (TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
310 regs->tstate &= ~(TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
311 regs->tstate |= tstate;
312 }
313 }
314
315 if (!ret) {
316 /* TPC, TNPC */
317 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
318 ®s->tpc,
319 33 * sizeof(u64),
320 35 * sizeof(u64));
321 }
322
323 if (!ret) {
324 unsigned long y = regs->y;
325
326 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
327 &y,
328 35 * sizeof(u64),
329 36 * sizeof(u64));
330 if (!ret)
331 regs->y = y;
332 }
333
334 if (!ret)
335 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
336 36 * sizeof(u64), -1);
337
338 return ret;
339}
340
341static int fpregs64_get(struct task_struct *target,
342 const struct user_regset *regset,
343 struct membuf to)
344{
345 struct thread_info *t = task_thread_info(target);
346 unsigned long fprs;
347
348 if (target == current)
349 save_and_clear_fpu();
350
351 fprs = t->fpsaved[0];
352
353 if (fprs & FPRS_DL)
354 membuf_write(&to, t->fpregs, 16 * sizeof(u64));
355 else
356 membuf_zero(&to, 16 * sizeof(u64));
357
358 if (fprs & FPRS_DU)
359 membuf_write(&to, t->fpregs + 16, 16 * sizeof(u64));
360 else
361 membuf_zero(&to, 16 * sizeof(u64));
362 if (fprs & FPRS_FEF) {
363 membuf_store(&to, t->xfsr[0]);
364 membuf_store(&to, t->gsr[0]);
365 } else {
366 membuf_zero(&to, 2 * sizeof(u64));
367 }
368 return membuf_store(&to, fprs);
369}
370
371static int fpregs64_set(struct task_struct *target,
372 const struct user_regset *regset,
373 unsigned int pos, unsigned int count,
374 const void *kbuf, const void __user *ubuf)
375{
376 unsigned long *fpregs = task_thread_info(target)->fpregs;
377 unsigned long fprs;
378 int ret;
379
380 if (target == current)
381 save_and_clear_fpu();
382
383 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
384 fpregs,
385 0, 32 * sizeof(u64));
386 if (!ret)
387 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
388 task_thread_info(target)->xfsr,
389 32 * sizeof(u64),
390 33 * sizeof(u64));
391 if (!ret)
392 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
393 task_thread_info(target)->gsr,
394 33 * sizeof(u64),
395 34 * sizeof(u64));
396
397 fprs = task_thread_info(target)->fpsaved[0];
398 if (!ret && count > 0) {
399 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
400 &fprs,
401 34 * sizeof(u64),
402 35 * sizeof(u64));
403 }
404
405 fprs |= (FPRS_FEF | FPRS_DL | FPRS_DU);
406 task_thread_info(target)->fpsaved[0] = fprs;
407
408 if (!ret)
409 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
410 35 * sizeof(u64), -1);
411 return ret;
412}
413
414static const struct user_regset sparc64_regsets[] = {
415 /* Format is:
416 * G0 --> G7
417 * O0 --> O7
418 * L0 --> L7
419 * I0 --> I7
420 * TSTATE, TPC, TNPC, Y
421 */
422 [REGSET_GENERAL] = {
423 .core_note_type = NT_PRSTATUS,
424 .n = 36,
425 .size = sizeof(u64), .align = sizeof(u64),
426 .regset_get = genregs64_get, .set = genregs64_set
427 },
428 /* Format is:
429 * F0 --> F63
430 * FSR
431 * GSR
432 * FPRS
433 */
434 [REGSET_FP] = {
435 .core_note_type = NT_PRFPREG,
436 .n = 35,
437 .size = sizeof(u64), .align = sizeof(u64),
438 .regset_get = fpregs64_get, .set = fpregs64_set
439 },
440};
441
442static int getregs64_get(struct task_struct *target,
443 const struct user_regset *regset,
444 struct membuf to)
445{
446 const struct pt_regs *regs = task_pt_regs(target);
447
448 if (target == current)
449 flushw_user();
450
451 membuf_write(&to, regs->u_regs + 1, 15 * sizeof(u64));
452 membuf_store(&to, (u64)0);
453 membuf_write(&to, ®s->tstate, 3 * sizeof(u64));
454 return membuf_store(&to, (u64)regs->y);
455}
456
457static int setregs64_set(struct task_struct *target,
458 const struct user_regset *regset,
459 unsigned int pos, unsigned int count,
460 const void *kbuf, const void __user *ubuf)
461{
462 struct pt_regs *regs = task_pt_regs(target);
463 unsigned long y = regs->y;
464 unsigned long tstate;
465 int ret;
466
467 if (target == current)
468 flushw_user();
469
470 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
471 regs->u_regs + 1,
472 0 * sizeof(u64),
473 15 * sizeof(u64));
474 if (ret)
475 return ret;
476 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
477 15 * sizeof(u64), 16 * sizeof(u64));
478 /* TSTATE */
479 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
480 &tstate,
481 16 * sizeof(u64),
482 17 * sizeof(u64));
483 if (ret)
484 return ret;
485 /* Only the condition codes and the "in syscall"
486 * state can be modified in the %tstate register.
487 */
488 tstate &= (TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
489 regs->tstate &= ~(TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
490 regs->tstate |= tstate;
491
492 /* TPC, TNPC */
493 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
494 ®s->tpc,
495 17 * sizeof(u64),
496 19 * sizeof(u64));
497 if (ret)
498 return ret;
499 /* Y */
500 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
501 &y,
502 19 * sizeof(u64),
503 20 * sizeof(u64));
504 if (!ret)
505 regs->y = y;
506 return ret;
507}
508
509static const struct user_regset ptrace64_regsets[] = {
510 /* Format is:
511 * G1 --> G7
512 * O0 --> O7
513 * 0
514 * TSTATE, TPC, TNPC, Y
515 */
516 [REGSET_GENERAL] = {
517 .n = 20, .size = sizeof(u64),
518 .regset_get = getregs64_get, .set = setregs64_set,
519 },
520};
521
522static const struct user_regset_view ptrace64_view = {
523 .regsets = ptrace64_regsets, .n = ARRAY_SIZE(ptrace64_regsets)
524};
525
526static const struct user_regset_view user_sparc64_view = {
527 .name = "sparc64", .e_machine = EM_SPARCV9,
528 .regsets = sparc64_regsets, .n = ARRAY_SIZE(sparc64_regsets)
529};
530
531#ifdef CONFIG_COMPAT
532static int genregs32_get(struct task_struct *target,
533 const struct user_regset *regset,
534 struct membuf to)
535{
536 const struct pt_regs *regs = task_pt_regs(target);
537 u32 uregs[16];
538 int i;
539
540 if (target == current)
541 flushw_user();
542
543 for (i = 0; i < 16; i++)
544 membuf_store(&to, (u32)regs->u_regs[i]);
545 if (!to.left)
546 return 0;
547 if (get_from_target(target, regs->u_regs[UREG_I6],
548 uregs, sizeof(uregs)))
549 return -EFAULT;
550 membuf_write(&to, uregs, 16 * sizeof(u32));
551 membuf_store(&to, (u32)tstate_to_psr(regs->tstate));
552 membuf_store(&to, (u32)(regs->tpc));
553 membuf_store(&to, (u32)(regs->tnpc));
554 membuf_store(&to, (u32)(regs->y));
555 return membuf_zero(&to, 2 * sizeof(u32));
556}
557
558static int genregs32_set(struct task_struct *target,
559 const struct user_regset *regset,
560 unsigned int pos, unsigned int count,
561 const void *kbuf, const void __user *ubuf)
562{
563 struct pt_regs *regs = task_pt_regs(target);
564 compat_ulong_t __user *reg_window;
565 const compat_ulong_t *k = kbuf;
566 const compat_ulong_t __user *u = ubuf;
567 compat_ulong_t reg;
568
569 if (target == current)
570 flushw_user();
571
572 pos /= sizeof(reg);
573 count /= sizeof(reg);
574
575 if (kbuf) {
576 for (; count > 0 && pos < 16; count--)
577 regs->u_regs[pos++] = *k++;
578
579 reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
580 reg_window -= 16;
581 if (target == current) {
582 for (; count > 0 && pos < 32; count--) {
583 if (put_user(*k++, ®_window[pos++]))
584 return -EFAULT;
585 }
586 } else {
587 for (; count > 0 && pos < 32; count--) {
588 if (access_process_vm(target,
589 (unsigned long)
590 ®_window[pos],
591 (void *) k,
592 sizeof(*k),
593 FOLL_FORCE | FOLL_WRITE)
594 != sizeof(*k))
595 return -EFAULT;
596 k++;
597 pos++;
598 }
599 }
600 } else {
601 for (; count > 0 && pos < 16; count--) {
602 if (get_user(reg, u++))
603 return -EFAULT;
604 regs->u_regs[pos++] = reg;
605 }
606
607 reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
608 reg_window -= 16;
609 if (target == current) {
610 for (; count > 0 && pos < 32; count--) {
611 if (get_user(reg, u++) ||
612 put_user(reg, ®_window[pos++]))
613 return -EFAULT;
614 }
615 } else {
616 for (; count > 0 && pos < 32; count--) {
617 if (get_user(reg, u++))
618 return -EFAULT;
619 if (access_process_vm(target,
620 (unsigned long)
621 ®_window[pos],
622 ®, sizeof(reg),
623 FOLL_FORCE | FOLL_WRITE)
624 != sizeof(reg))
625 return -EFAULT;
626 pos++;
627 u++;
628 }
629 }
630 }
631 while (count > 0) {
632 unsigned long tstate;
633
634 if (kbuf)
635 reg = *k++;
636 else if (get_user(reg, u++))
637 return -EFAULT;
638
639 switch (pos) {
640 case 32: /* PSR */
641 tstate = regs->tstate;
642 tstate &= ~(TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
643 tstate |= psr_to_tstate_icc(reg);
644 if (reg & PSR_SYSCALL)
645 tstate |= TSTATE_SYSCALL;
646 regs->tstate = tstate;
647 break;
648 case 33: /* PC */
649 regs->tpc = reg;
650 break;
651 case 34: /* NPC */
652 regs->tnpc = reg;
653 break;
654 case 35: /* Y */
655 regs->y = reg;
656 break;
657 case 36: /* WIM */
658 case 37: /* TBR */
659 break;
660 default:
661 goto finish;
662 }
663
664 pos++;
665 count--;
666 }
667finish:
668 pos *= sizeof(reg);
669 count *= sizeof(reg);
670
671 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
672 38 * sizeof(reg), -1);
673 return 0;
674}
675
676static int fpregs32_get(struct task_struct *target,
677 const struct user_regset *regset,
678 struct membuf to)
679{
680 struct thread_info *t = task_thread_info(target);
681 bool enabled;
682
683 if (target == current)
684 save_and_clear_fpu();
685
686 enabled = t->fpsaved[0] & FPRS_FEF;
687
688 membuf_write(&to, t->fpregs, 32 * sizeof(u32));
689 membuf_zero(&to, sizeof(u32));
690 if (enabled)
691 membuf_store(&to, (u32)t->xfsr[0]);
692 else
693 membuf_zero(&to, sizeof(u32));
694 membuf_store(&to, (u32)((enabled << 8) | (8 << 16)));
695 return membuf_zero(&to, 64 * sizeof(u32));
696}
697
698static int fpregs32_set(struct task_struct *target,
699 const struct user_regset *regset,
700 unsigned int pos, unsigned int count,
701 const void *kbuf, const void __user *ubuf)
702{
703 unsigned long *fpregs = task_thread_info(target)->fpregs;
704 unsigned long fprs;
705 int ret;
706
707 if (target == current)
708 save_and_clear_fpu();
709
710 fprs = task_thread_info(target)->fpsaved[0];
711
712 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
713 fpregs,
714 0, 32 * sizeof(u32));
715 if (!ret)
716 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
717 32 * sizeof(u32),
718 33 * sizeof(u32));
719 if (!ret && count > 0) {
720 compat_ulong_t fsr;
721 unsigned long val;
722
723 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
724 &fsr,
725 33 * sizeof(u32),
726 34 * sizeof(u32));
727 if (!ret) {
728 val = task_thread_info(target)->xfsr[0];
729 val &= 0xffffffff00000000UL;
730 val |= fsr;
731 task_thread_info(target)->xfsr[0] = val;
732 }
733 }
734
735 fprs |= (FPRS_FEF | FPRS_DL);
736 task_thread_info(target)->fpsaved[0] = fprs;
737
738 if (!ret)
739 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
740 34 * sizeof(u32), -1);
741 return ret;
742}
743
744static const struct user_regset sparc32_regsets[] = {
745 /* Format is:
746 * G0 --> G7
747 * O0 --> O7
748 * L0 --> L7
749 * I0 --> I7
750 * PSR, PC, nPC, Y, WIM, TBR
751 */
752 [REGSET_GENERAL] = {
753 .core_note_type = NT_PRSTATUS,
754 .n = 38,
755 .size = sizeof(u32), .align = sizeof(u32),
756 .regset_get = genregs32_get, .set = genregs32_set
757 },
758 /* Format is:
759 * F0 --> F31
760 * empty 32-bit word
761 * FSR (32--bit word)
762 * FPU QUEUE COUNT (8-bit char)
763 * FPU QUEUE ENTRYSIZE (8-bit char)
764 * FPU ENABLED (8-bit char)
765 * empty 8-bit char
766 * FPU QUEUE (64 32-bit ints)
767 */
768 [REGSET_FP] = {
769 .core_note_type = NT_PRFPREG,
770 .n = 99,
771 .size = sizeof(u32), .align = sizeof(u32),
772 .regset_get = fpregs32_get, .set = fpregs32_set
773 },
774};
775
776static int getregs_get(struct task_struct *target,
777 const struct user_regset *regset,
778 struct membuf to)
779{
780 const struct pt_regs *regs = task_pt_regs(target);
781 int i;
782
783 if (target == current)
784 flushw_user();
785
786 membuf_store(&to, (u32)tstate_to_psr(regs->tstate));
787 membuf_store(&to, (u32)(regs->tpc));
788 membuf_store(&to, (u32)(regs->tnpc));
789 membuf_store(&to, (u32)(regs->y));
790 for (i = 1; i < 16; i++)
791 membuf_store(&to, (u32)regs->u_regs[i]);
792 return to.left;
793}
794
795static int setregs_set(struct task_struct *target,
796 const struct user_regset *regset,
797 unsigned int pos, unsigned int count,
798 const void *kbuf, const void __user *ubuf)
799{
800 struct pt_regs *regs = task_pt_regs(target);
801 unsigned long tstate;
802 u32 uregs[19];
803 int i, ret;
804
805 if (target == current)
806 flushw_user();
807
808 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
809 uregs,
810 0, 19 * sizeof(u32));
811 if (ret)
812 return ret;
813
814 tstate = regs->tstate;
815 tstate &= ~(TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
816 tstate |= psr_to_tstate_icc(uregs[0]);
817 if (uregs[0] & PSR_SYSCALL)
818 tstate |= TSTATE_SYSCALL;
819 regs->tstate = tstate;
820 regs->tpc = uregs[1];
821 regs->tnpc = uregs[2];
822 regs->y = uregs[3];
823
824 for (i = 1; i < 15; i++)
825 regs->u_regs[i] = uregs[3 + i];
826 return 0;
827}
828
829static int getfpregs_get(struct task_struct *target,
830 const struct user_regset *regset,
831 struct membuf to)
832{
833 struct thread_info *t = task_thread_info(target);
834
835 if (target == current)
836 save_and_clear_fpu();
837
838 membuf_write(&to, t->fpregs, 32 * sizeof(u32));
839 if (t->fpsaved[0] & FPRS_FEF)
840 membuf_store(&to, (u32)t->xfsr[0]);
841 else
842 membuf_zero(&to, sizeof(u32));
843 return membuf_zero(&to, 35 * sizeof(u32));
844}
845
846static int setfpregs_set(struct task_struct *target,
847 const struct user_regset *regset,
848 unsigned int pos, unsigned int count,
849 const void *kbuf, const void __user *ubuf)
850{
851 unsigned long *fpregs = task_thread_info(target)->fpregs;
852 unsigned long fprs;
853 int ret;
854
855 if (target == current)
856 save_and_clear_fpu();
857
858 fprs = task_thread_info(target)->fpsaved[0];
859
860 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
861 fpregs,
862 0, 32 * sizeof(u32));
863 if (!ret) {
864 compat_ulong_t fsr;
865 unsigned long val;
866
867 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
868 &fsr,
869 32 * sizeof(u32),
870 33 * sizeof(u32));
871 if (!ret) {
872 val = task_thread_info(target)->xfsr[0];
873 val &= 0xffffffff00000000UL;
874 val |= fsr;
875 task_thread_info(target)->xfsr[0] = val;
876 }
877 }
878
879 fprs |= (FPRS_FEF | FPRS_DL);
880 task_thread_info(target)->fpsaved[0] = fprs;
881 return ret;
882}
883
884static const struct user_regset ptrace32_regsets[] = {
885 [REGSET_GENERAL] = {
886 .n = 19, .size = sizeof(u32),
887 .regset_get = getregs_get, .set = setregs_set,
888 },
889 [REGSET_FP] = {
890 .n = 68, .size = sizeof(u32),
891 .regset_get = getfpregs_get, .set = setfpregs_set,
892 },
893};
894
895static const struct user_regset_view ptrace32_view = {
896 .regsets = ptrace32_regsets, .n = ARRAY_SIZE(ptrace32_regsets)
897};
898
899static const struct user_regset_view user_sparc32_view = {
900 .name = "sparc", .e_machine = EM_SPARC,
901 .regsets = sparc32_regsets, .n = ARRAY_SIZE(sparc32_regsets)
902};
903#endif /* CONFIG_COMPAT */
904
905const struct user_regset_view *task_user_regset_view(struct task_struct *task)
906{
907#ifdef CONFIG_COMPAT
908 if (test_tsk_thread_flag(task, TIF_32BIT))
909 return &user_sparc32_view;
910#endif
911 return &user_sparc64_view;
912}
913
914#ifdef CONFIG_COMPAT
915struct compat_fps {
916 unsigned int regs[32];
917 unsigned int fsr;
918 unsigned int flags;
919 unsigned int extra;
920 unsigned int fpqd;
921 struct compat_fq {
922 unsigned int insnaddr;
923 unsigned int insn;
924 } fpq[16];
925};
926
927long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
928 compat_ulong_t caddr, compat_ulong_t cdata)
929{
930 compat_ulong_t caddr2 = task_pt_regs(current)->u_regs[UREG_I4];
931 struct pt_regs32 __user *pregs;
932 struct compat_fps __user *fps;
933 unsigned long addr2 = caddr2;
934 unsigned long addr = caddr;
935 unsigned long data = cdata;
936 int ret;
937
938 pregs = (struct pt_regs32 __user *) addr;
939 fps = (struct compat_fps __user *) addr;
940
941 switch (request) {
942 case PTRACE_PEEKUSR:
943 ret = (addr != 0) ? -EIO : 0;
944 break;
945
946 case PTRACE_GETREGS:
947 ret = copy_regset_to_user(child, &ptrace32_view,
948 REGSET_GENERAL, 0,
949 19 * sizeof(u32),
950 pregs);
951 break;
952
953 case PTRACE_SETREGS:
954 ret = copy_regset_from_user(child, &ptrace32_view,
955 REGSET_GENERAL, 0,
956 19 * sizeof(u32),
957 pregs);
958 break;
959
960 case PTRACE_GETFPREGS:
961 ret = copy_regset_to_user(child, &ptrace32_view,
962 REGSET_FP, 0,
963 68 * sizeof(u32),
964 fps);
965 break;
966
967 case PTRACE_SETFPREGS:
968 ret = copy_regset_from_user(child, &ptrace32_view,
969 REGSET_FP, 0,
970 33 * sizeof(u32),
971 fps);
972 break;
973
974 case PTRACE_READTEXT:
975 case PTRACE_READDATA:
976 ret = ptrace_readdata(child, addr,
977 (char __user *)addr2, data);
978 if (ret == data)
979 ret = 0;
980 else if (ret >= 0)
981 ret = -EIO;
982 break;
983
984 case PTRACE_WRITETEXT:
985 case PTRACE_WRITEDATA:
986 ret = ptrace_writedata(child, (char __user *) addr2,
987 addr, data);
988 if (ret == data)
989 ret = 0;
990 else if (ret >= 0)
991 ret = -EIO;
992 break;
993
994 default:
995 if (request == PTRACE_SPARC_DETACH)
996 request = PTRACE_DETACH;
997 ret = compat_ptrace_request(child, request, addr, data);
998 break;
999 }
1000
1001 return ret;
1002}
1003#endif /* CONFIG_COMPAT */
1004
1005struct fps {
1006 unsigned int regs[64];
1007 unsigned long fsr;
1008};
1009
1010long arch_ptrace(struct task_struct *child, long request,
1011 unsigned long addr, unsigned long data)
1012{
1013 const struct user_regset_view *view = task_user_regset_view(current);
1014 unsigned long addr2 = task_pt_regs(current)->u_regs[UREG_I4];
1015 struct pt_regs __user *pregs;
1016 struct fps __user *fps;
1017 void __user *addr2p;
1018 int ret;
1019
1020 pregs = (struct pt_regs __user *) addr;
1021 fps = (struct fps __user *) addr;
1022 addr2p = (void __user *) addr2;
1023
1024 switch (request) {
1025 case PTRACE_PEEKUSR:
1026 ret = (addr != 0) ? -EIO : 0;
1027 break;
1028
1029 case PTRACE_GETREGS64:
1030 ret = copy_regset_to_user(child, &ptrace64_view,
1031 REGSET_GENERAL, 0,
1032 19 * sizeof(u64),
1033 pregs);
1034 break;
1035
1036 case PTRACE_SETREGS64:
1037 ret = copy_regset_from_user(child, &ptrace64_view,
1038 REGSET_GENERAL, 0,
1039 19 * sizeof(u64),
1040 pregs);
1041 break;
1042
1043 case PTRACE_GETFPREGS64:
1044 ret = copy_regset_to_user(child, view, REGSET_FP,
1045 0 * sizeof(u64),
1046 33 * sizeof(u64),
1047 fps);
1048 break;
1049
1050 case PTRACE_SETFPREGS64:
1051 ret = copy_regset_from_user(child, view, REGSET_FP,
1052 0 * sizeof(u64),
1053 33 * sizeof(u64),
1054 fps);
1055 break;
1056
1057 case PTRACE_READTEXT:
1058 case PTRACE_READDATA:
1059 ret = ptrace_readdata(child, addr, addr2p, data);
1060 if (ret == data)
1061 ret = 0;
1062 else if (ret >= 0)
1063 ret = -EIO;
1064 break;
1065
1066 case PTRACE_WRITETEXT:
1067 case PTRACE_WRITEDATA:
1068 ret = ptrace_writedata(child, addr2p, addr, data);
1069 if (ret == data)
1070 ret = 0;
1071 else if (ret >= 0)
1072 ret = -EIO;
1073 break;
1074
1075 default:
1076 if (request == PTRACE_SPARC_DETACH)
1077 request = PTRACE_DETACH;
1078 ret = ptrace_request(child, request, addr, data);
1079 break;
1080 }
1081
1082 return ret;
1083}
1084
1085asmlinkage int syscall_trace_enter(struct pt_regs *regs)
1086{
1087 int ret = 0;
1088
1089 /* do the secure computing check first */
1090 secure_computing_strict(regs->u_regs[UREG_G1]);
1091
1092 if (test_thread_flag(TIF_NOHZ))
1093 user_exit();
1094
1095 if (test_thread_flag(TIF_SYSCALL_TRACE))
1096 ret = ptrace_report_syscall_entry(regs);
1097
1098 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1099 trace_sys_enter(regs, regs->u_regs[UREG_G1]);
1100
1101 audit_syscall_entry(regs->u_regs[UREG_G1], regs->u_regs[UREG_I0],
1102 regs->u_regs[UREG_I1], regs->u_regs[UREG_I2],
1103 regs->u_regs[UREG_I3]);
1104
1105 return ret;
1106}
1107
1108asmlinkage void syscall_trace_leave(struct pt_regs *regs)
1109{
1110 if (test_thread_flag(TIF_NOHZ))
1111 user_exit();
1112
1113 audit_syscall_exit(regs);
1114
1115 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1116 trace_sys_exit(regs, regs->u_regs[UREG_I0]);
1117
1118 if (test_thread_flag(TIF_SYSCALL_TRACE))
1119 ptrace_report_syscall_exit(regs, 0);
1120
1121 if (test_thread_flag(TIF_NOHZ))
1122 user_enter();
1123}
1124
1125/**
1126 * regs_query_register_offset() - query register offset from its name
1127 * @name: the name of a register
1128 *
1129 * regs_query_register_offset() returns the offset of a register in struct
1130 * pt_regs from its name. If the name is invalid, this returns -EINVAL;
1131 */
1132int regs_query_register_offset(const char *name)
1133{
1134 const struct pt_regs_offset *roff;
1135
1136 for (roff = regoffset_table; roff->name != NULL; roff++)
1137 if (!strcmp(roff->name, name))
1138 return roff->offset;
1139 return -EINVAL;
1140}
1141
1142/**
1143 * regs_within_kernel_stack() - check the address in the stack
1144 * @regs: pt_regs which contains kernel stack pointer.
1145 * @addr: address which is checked.
1146 *
1147 * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
1148 * If @addr is within the kernel stack, it returns true. If not, returns false.
1149 */
1150static inline int regs_within_kernel_stack(struct pt_regs *regs,
1151 unsigned long addr)
1152{
1153 unsigned long ksp = kernel_stack_pointer(regs) + STACK_BIAS;
1154 return ((addr & ~(THREAD_SIZE - 1)) ==
1155 (ksp & ~(THREAD_SIZE - 1)));
1156}
1157
1158/**
1159 * regs_get_kernel_stack_nth() - get Nth entry of the stack
1160 * @regs: pt_regs which contains kernel stack pointer.
1161 * @n: stack entry number.
1162 *
1163 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1164 * is specified by @regs. If the @n th entry is NOT in the kernel stack,
1165 * this returns 0.
1166 */
1167unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1168{
1169 unsigned long ksp = kernel_stack_pointer(regs) + STACK_BIAS;
1170 unsigned long *addr = (unsigned long *)ksp;
1171 addr += n;
1172 if (regs_within_kernel_stack(regs, (unsigned long)addr))
1173 return *addr;
1174 else
1175 return 0;
1176}