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-rw-r--r--arch/arm64/kernel/ptrace.c1126
1 files changed, 1126 insertions, 0 deletions
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
new file mode 100644
index 000000000000..ac3550ecc7b5
--- /dev/null
+++ b/arch/arm64/kernel/ptrace.c
@@ -0,0 +1,1126 @@
1/*
2 * Based on arch/arm/kernel/ptrace.c
3 *
4 * By Ross Biro 1/23/92
5 * edited by Linus Torvalds
6 * ARM modifications Copyright (C) 2000 Russell King
7 * Copyright (C) 2012 ARM Ltd.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program. If not, see <http://www.gnu.org/licenses/>.
20 */
21
22#include <linux/kernel.h>
23#include <linux/sched.h>
24#include <linux/mm.h>
25#include <linux/smp.h>
26#include <linux/ptrace.h>
27#include <linux/user.h>
28#include <linux/security.h>
29#include <linux/init.h>
30#include <linux/signal.h>
31#include <linux/uaccess.h>
32#include <linux/perf_event.h>
33#include <linux/hw_breakpoint.h>
34#include <linux/regset.h>
35#include <linux/tracehook.h>
36#include <linux/elf.h>
37
38#include <asm/compat.h>
39#include <asm/debug-monitors.h>
40#include <asm/pgtable.h>
41#include <asm/traps.h>
42#include <asm/system_misc.h>
43
44/*
45 * TODO: does not yet catch signals sent when the child dies.
46 * in exit.c or in signal.c.
47 */
48
49/*
50 * Called by kernel/ptrace.c when detaching..
51 */
52void ptrace_disable(struct task_struct *child)
53{
54}
55
56/*
57 * Handle hitting a breakpoint.
58 */
59static int ptrace_break(struct pt_regs *regs)
60{
61 siginfo_t info = {
62 .si_signo = SIGTRAP,
63 .si_errno = 0,
64 .si_code = TRAP_BRKPT,
65 .si_addr = (void __user *)instruction_pointer(regs),
66 };
67
68 force_sig_info(SIGTRAP, &info, current);
69 return 0;
70}
71
72static int arm64_break_trap(unsigned long addr, unsigned int esr,
73 struct pt_regs *regs)
74{
75 return ptrace_break(regs);
76}
77
78#ifdef CONFIG_HAVE_HW_BREAKPOINT
79/*
80 * Handle hitting a HW-breakpoint.
81 */
82static void ptrace_hbptriggered(struct perf_event *bp,
83 struct perf_sample_data *data,
84 struct pt_regs *regs)
85{
86 struct arch_hw_breakpoint *bkpt = counter_arch_bp(bp);
87 siginfo_t info = {
88 .si_signo = SIGTRAP,
89 .si_errno = 0,
90 .si_code = TRAP_HWBKPT,
91 .si_addr = (void __user *)(bkpt->trigger),
92 };
93
94#ifdef CONFIG_COMPAT
95 int i;
96
97 if (!is_compat_task())
98 goto send_sig;
99
100 for (i = 0; i < ARM_MAX_BRP; ++i) {
101 if (current->thread.debug.hbp_break[i] == bp) {
102 info.si_errno = (i << 1) + 1;
103 break;
104 }
105 }
106 for (i = ARM_MAX_BRP; i < ARM_MAX_HBP_SLOTS && !bp; ++i) {
107 if (current->thread.debug.hbp_watch[i] == bp) {
108 info.si_errno = -((i << 1) + 1);
109 break;
110 }
111 }
112
113send_sig:
114#endif
115 force_sig_info(SIGTRAP, &info, current);
116}
117
118/*
119 * Unregister breakpoints from this task and reset the pointers in
120 * the thread_struct.
121 */
122void flush_ptrace_hw_breakpoint(struct task_struct *tsk)
123{
124 int i;
125 struct thread_struct *t = &tsk->thread;
126
127 for (i = 0; i < ARM_MAX_BRP; i++) {
128 if (t->debug.hbp_break[i]) {
129 unregister_hw_breakpoint(t->debug.hbp_break[i]);
130 t->debug.hbp_break[i] = NULL;
131 }
132 }
133
134 for (i = 0; i < ARM_MAX_WRP; i++) {
135 if (t->debug.hbp_watch[i]) {
136 unregister_hw_breakpoint(t->debug.hbp_watch[i]);
137 t->debug.hbp_watch[i] = NULL;
138 }
139 }
140}
141
142void ptrace_hw_copy_thread(struct task_struct *tsk)
143{
144 memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
145}
146
147static struct perf_event *ptrace_hbp_get_event(unsigned int note_type,
148 struct task_struct *tsk,
149 unsigned long idx)
150{
151 struct perf_event *bp = ERR_PTR(-EINVAL);
152
153 switch (note_type) {
154 case NT_ARM_HW_BREAK:
155 if (idx < ARM_MAX_BRP)
156 bp = tsk->thread.debug.hbp_break[idx];
157 break;
158 case NT_ARM_HW_WATCH:
159 if (idx < ARM_MAX_WRP)
160 bp = tsk->thread.debug.hbp_watch[idx];
161 break;
162 }
163
164 return bp;
165}
166
167static int ptrace_hbp_set_event(unsigned int note_type,
168 struct task_struct *tsk,
169 unsigned long idx,
170 struct perf_event *bp)
171{
172 int err = -EINVAL;
173
174 switch (note_type) {
175 case NT_ARM_HW_BREAK:
176 if (idx < ARM_MAX_BRP) {
177 tsk->thread.debug.hbp_break[idx] = bp;
178 err = 0;
179 }
180 break;
181 case NT_ARM_HW_WATCH:
182 if (idx < ARM_MAX_WRP) {
183 tsk->thread.debug.hbp_watch[idx] = bp;
184 err = 0;
185 }
186 break;
187 }
188
189 return err;
190}
191
192static struct perf_event *ptrace_hbp_create(unsigned int note_type,
193 struct task_struct *tsk,
194 unsigned long idx)
195{
196 struct perf_event *bp;
197 struct perf_event_attr attr;
198 int err, type;
199
200 switch (note_type) {
201 case NT_ARM_HW_BREAK:
202 type = HW_BREAKPOINT_X;
203 break;
204 case NT_ARM_HW_WATCH:
205 type = HW_BREAKPOINT_RW;
206 break;
207 default:
208 return ERR_PTR(-EINVAL);
209 }
210
211 ptrace_breakpoint_init(&attr);
212
213 /*
214 * Initialise fields to sane defaults
215 * (i.e. values that will pass validation).
216 */
217 attr.bp_addr = 0;
218 attr.bp_len = HW_BREAKPOINT_LEN_4;
219 attr.bp_type = type;
220 attr.disabled = 1;
221
222 bp = register_user_hw_breakpoint(&attr, ptrace_hbptriggered, NULL, tsk);
223 if (IS_ERR(bp))
224 return bp;
225
226 err = ptrace_hbp_set_event(note_type, tsk, idx, bp);
227 if (err)
228 return ERR_PTR(err);
229
230 return bp;
231}
232
233static int ptrace_hbp_fill_attr_ctrl(unsigned int note_type,
234 struct arch_hw_breakpoint_ctrl ctrl,
235 struct perf_event_attr *attr)
236{
237 int err, len, type;
238
239 err = arch_bp_generic_fields(ctrl, &len, &type);
240 if (err)
241 return err;
242
243 switch (note_type) {
244 case NT_ARM_HW_BREAK:
245 if ((type & HW_BREAKPOINT_X) != type)
246 return -EINVAL;
247 break;
248 case NT_ARM_HW_WATCH:
249 if ((type & HW_BREAKPOINT_RW) != type)
250 return -EINVAL;
251 break;
252 default:
253 return -EINVAL;
254 }
255
256 attr->bp_len = len;
257 attr->bp_type = type;
258 attr->disabled = !ctrl.enabled;
259
260 return 0;
261}
262
263static int ptrace_hbp_get_resource_info(unsigned int note_type, u32 *info)
264{
265 u8 num;
266 u32 reg = 0;
267
268 switch (note_type) {
269 case NT_ARM_HW_BREAK:
270 num = hw_breakpoint_slots(TYPE_INST);
271 break;
272 case NT_ARM_HW_WATCH:
273 num = hw_breakpoint_slots(TYPE_DATA);
274 break;
275 default:
276 return -EINVAL;
277 }
278
279 reg |= debug_monitors_arch();
280 reg <<= 8;
281 reg |= num;
282
283 *info = reg;
284 return 0;
285}
286
287static int ptrace_hbp_get_ctrl(unsigned int note_type,
288 struct task_struct *tsk,
289 unsigned long idx,
290 u32 *ctrl)
291{
292 struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
293
294 if (IS_ERR(bp))
295 return PTR_ERR(bp);
296
297 *ctrl = bp ? encode_ctrl_reg(counter_arch_bp(bp)->ctrl) : 0;
298 return 0;
299}
300
301static int ptrace_hbp_get_addr(unsigned int note_type,
302 struct task_struct *tsk,
303 unsigned long idx,
304 u64 *addr)
305{
306 struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
307
308 if (IS_ERR(bp))
309 return PTR_ERR(bp);
310
311 *addr = bp ? bp->attr.bp_addr : 0;
312 return 0;
313}
314
315static struct perf_event *ptrace_hbp_get_initialised_bp(unsigned int note_type,
316 struct task_struct *tsk,
317 unsigned long idx)
318{
319 struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
320
321 if (!bp)
322 bp = ptrace_hbp_create(note_type, tsk, idx);
323
324 return bp;
325}
326
327static int ptrace_hbp_set_ctrl(unsigned int note_type,
328 struct task_struct *tsk,
329 unsigned long idx,
330 u32 uctrl)
331{
332 int err;
333 struct perf_event *bp;
334 struct perf_event_attr attr;
335 struct arch_hw_breakpoint_ctrl ctrl;
336
337 bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx);
338 if (IS_ERR(bp)) {
339 err = PTR_ERR(bp);
340 return err;
341 }
342
343 attr = bp->attr;
344 decode_ctrl_reg(uctrl, &ctrl);
345 err = ptrace_hbp_fill_attr_ctrl(note_type, ctrl, &attr);
346 if (err)
347 return err;
348
349 return modify_user_hw_breakpoint(bp, &attr);
350}
351
352static int ptrace_hbp_set_addr(unsigned int note_type,
353 struct task_struct *tsk,
354 unsigned long idx,
355 u64 addr)
356{
357 int err;
358 struct perf_event *bp;
359 struct perf_event_attr attr;
360
361 bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx);
362 if (IS_ERR(bp)) {
363 err = PTR_ERR(bp);
364 return err;
365 }
366
367 attr = bp->attr;
368 attr.bp_addr = addr;
369 err = modify_user_hw_breakpoint(bp, &attr);
370 return err;
371}
372
373#define PTRACE_HBP_ADDR_SZ sizeof(u64)
374#define PTRACE_HBP_CTRL_SZ sizeof(u32)
375#define PTRACE_HBP_REG_OFF sizeof(u32)
376
377static int hw_break_get(struct task_struct *target,
378 const struct user_regset *regset,
379 unsigned int pos, unsigned int count,
380 void *kbuf, void __user *ubuf)
381{
382 unsigned int note_type = regset->core_note_type;
383 int ret, idx = 0, offset = PTRACE_HBP_REG_OFF, limit;
384 u32 info, ctrl;
385 u64 addr;
386
387 /* Resource info */
388 ret = ptrace_hbp_get_resource_info(note_type, &info);
389 if (ret)
390 return ret;
391
392 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &info, 0, 4);
393 if (ret)
394 return ret;
395
396 /* (address, ctrl) registers */
397 limit = regset->n * regset->size;
398 while (count && offset < limit) {
399 ret = ptrace_hbp_get_addr(note_type, target, idx, &addr);
400 if (ret)
401 return ret;
402 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &addr,
403 offset, offset + PTRACE_HBP_ADDR_SZ);
404 if (ret)
405 return ret;
406 offset += PTRACE_HBP_ADDR_SZ;
407
408 ret = ptrace_hbp_get_ctrl(note_type, target, idx, &ctrl);
409 if (ret)
410 return ret;
411 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &ctrl,
412 offset, offset + PTRACE_HBP_CTRL_SZ);
413 if (ret)
414 return ret;
415 offset += PTRACE_HBP_CTRL_SZ;
416 idx++;
417 }
418
419 return 0;
420}
421
422static int hw_break_set(struct task_struct *target,
423 const struct user_regset *regset,
424 unsigned int pos, unsigned int count,
425 const void *kbuf, const void __user *ubuf)
426{
427 unsigned int note_type = regset->core_note_type;
428 int ret, idx = 0, offset = PTRACE_HBP_REG_OFF, limit;
429 u32 ctrl;
430 u64 addr;
431
432 /* Resource info */
433 ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, 4);
434 if (ret)
435 return ret;
436
437 /* (address, ctrl) registers */
438 limit = regset->n * regset->size;
439 while (count && offset < limit) {
440 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &addr,
441 offset, offset + PTRACE_HBP_ADDR_SZ);
442 if (ret)
443 return ret;
444 ret = ptrace_hbp_set_addr(note_type, target, idx, addr);
445 if (ret)
446 return ret;
447 offset += PTRACE_HBP_ADDR_SZ;
448
449 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl,
450 offset, offset + PTRACE_HBP_CTRL_SZ);
451 if (ret)
452 return ret;
453 ret = ptrace_hbp_set_ctrl(note_type, target, idx, ctrl);
454 if (ret)
455 return ret;
456 offset += PTRACE_HBP_CTRL_SZ;
457 idx++;
458 }
459
460 return 0;
461}
462#endif /* CONFIG_HAVE_HW_BREAKPOINT */
463
464static int gpr_get(struct task_struct *target,
465 const struct user_regset *regset,
466 unsigned int pos, unsigned int count,
467 void *kbuf, void __user *ubuf)
468{
469 struct user_pt_regs *uregs = &task_pt_regs(target)->user_regs;
470 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0, -1);
471}
472
473static int gpr_set(struct task_struct *target, const struct user_regset *regset,
474 unsigned int pos, unsigned int count,
475 const void *kbuf, const void __user *ubuf)
476{
477 int ret;
478 struct user_pt_regs newregs;
479
480 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newregs, 0, -1);
481 if (ret)
482 return ret;
483
484 if (!valid_user_regs(&newregs))
485 return -EINVAL;
486
487 task_pt_regs(target)->user_regs = newregs;
488 return 0;
489}
490
491/*
492 * TODO: update fp accessors for lazy context switching (sync/flush hwstate)
493 */
494static int fpr_get(struct task_struct *target, const struct user_regset *regset,
495 unsigned int pos, unsigned int count,
496 void *kbuf, void __user *ubuf)
497{
498 struct user_fpsimd_state *uregs;
499 uregs = &target->thread.fpsimd_state.user_fpsimd;
500 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0, -1);
501}
502
503static int fpr_set(struct task_struct *target, const struct user_regset *regset,
504 unsigned int pos, unsigned int count,
505 const void *kbuf, const void __user *ubuf)
506{
507 int ret;
508 struct user_fpsimd_state newstate;
509
510 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newstate, 0, -1);
511 if (ret)
512 return ret;
513
514 target->thread.fpsimd_state.user_fpsimd = newstate;
515 return ret;
516}
517
518static int tls_get(struct task_struct *target, const struct user_regset *regset,
519 unsigned int pos, unsigned int count,
520 void *kbuf, void __user *ubuf)
521{
522 unsigned long *tls = &target->thread.tp_value;
523 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, tls, 0, -1);
524}
525
526static int tls_set(struct task_struct *target, const struct user_regset *regset,
527 unsigned int pos, unsigned int count,
528 const void *kbuf, const void __user *ubuf)
529{
530 int ret;
531 unsigned long tls;
532
533 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tls, 0, -1);
534 if (ret)
535 return ret;
536
537 target->thread.tp_value = tls;
538 return ret;
539}
540
541enum aarch64_regset {
542 REGSET_GPR,
543 REGSET_FPR,
544 REGSET_TLS,
545#ifdef CONFIG_HAVE_HW_BREAKPOINT
546 REGSET_HW_BREAK,
547 REGSET_HW_WATCH,
548#endif
549};
550
551static const struct user_regset aarch64_regsets[] = {
552 [REGSET_GPR] = {
553 .core_note_type = NT_PRSTATUS,
554 .n = sizeof(struct user_pt_regs) / sizeof(u64),
555 .size = sizeof(u64),
556 .align = sizeof(u64),
557 .get = gpr_get,
558 .set = gpr_set
559 },
560 [REGSET_FPR] = {
561 .core_note_type = NT_PRFPREG,
562 .n = sizeof(struct user_fpsimd_state) / sizeof(u32),
563 /*
564 * We pretend we have 32-bit registers because the fpsr and
565 * fpcr are 32-bits wide.
566 */
567 .size = sizeof(u32),
568 .align = sizeof(u32),
569 .get = fpr_get,
570 .set = fpr_set
571 },
572 [REGSET_TLS] = {
573 .core_note_type = NT_ARM_TLS,
574 .n = 1,
575 .size = sizeof(void *),
576 .align = sizeof(void *),
577 .get = tls_get,
578 .set = tls_set,
579 },
580#ifdef CONFIG_HAVE_HW_BREAKPOINT
581 [REGSET_HW_BREAK] = {
582 .core_note_type = NT_ARM_HW_BREAK,
583 .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
584 .size = sizeof(u32),
585 .align = sizeof(u32),
586 .get = hw_break_get,
587 .set = hw_break_set,
588 },
589 [REGSET_HW_WATCH] = {
590 .core_note_type = NT_ARM_HW_WATCH,
591 .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
592 .size = sizeof(u32),
593 .align = sizeof(u32),
594 .get = hw_break_get,
595 .set = hw_break_set,
596 },
597#endif
598};
599
600static const struct user_regset_view user_aarch64_view = {
601 .name = "aarch64", .e_machine = EM_AARCH64,
602 .regsets = aarch64_regsets, .n = ARRAY_SIZE(aarch64_regsets)
603};
604
605#ifdef CONFIG_COMPAT
606#include <linux/compat.h>
607
608enum compat_regset {
609 REGSET_COMPAT_GPR,
610 REGSET_COMPAT_VFP,
611};
612
613static int compat_gpr_get(struct task_struct *target,
614 const struct user_regset *regset,
615 unsigned int pos, unsigned int count,
616 void *kbuf, void __user *ubuf)
617{
618 int ret = 0;
619 unsigned int i, start, num_regs;
620
621 /* Calculate the number of AArch32 registers contained in count */
622 num_regs = count / regset->size;
623
624 /* Convert pos into an register number */
625 start = pos / regset->size;
626
627 if (start + num_regs > regset->n)
628 return -EIO;
629
630 for (i = 0; i < num_regs; ++i) {
631 unsigned int idx = start + i;
632 void *reg;
633
634 switch (idx) {
635 case 15:
636 reg = (void *)&task_pt_regs(target)->pc;
637 break;
638 case 16:
639 reg = (void *)&task_pt_regs(target)->pstate;
640 break;
641 case 17:
642 reg = (void *)&task_pt_regs(target)->orig_x0;
643 break;
644 default:
645 reg = (void *)&task_pt_regs(target)->regs[idx];
646 }
647
648 ret = copy_to_user(ubuf, reg, sizeof(compat_ulong_t));
649
650 if (ret)
651 break;
652 else
653 ubuf += sizeof(compat_ulong_t);
654 }
655
656 return ret;
657}
658
659static int compat_gpr_set(struct task_struct *target,
660 const struct user_regset *regset,
661 unsigned int pos, unsigned int count,
662 const void *kbuf, const void __user *ubuf)
663{
664 struct pt_regs newregs;
665 int ret = 0;
666 unsigned int i, start, num_regs;
667
668 /* Calculate the number of AArch32 registers contained in count */
669 num_regs = count / regset->size;
670
671 /* Convert pos into an register number */
672 start = pos / regset->size;
673
674 if (start + num_regs > regset->n)
675 return -EIO;
676
677 newregs = *task_pt_regs(target);
678
679 for (i = 0; i < num_regs; ++i) {
680 unsigned int idx = start + i;
681 void *reg;
682
683 switch (idx) {
684 case 15:
685 reg = (void *)&newregs.pc;
686 break;
687 case 16:
688 reg = (void *)&newregs.pstate;
689 break;
690 case 17:
691 reg = (void *)&newregs.orig_x0;
692 break;
693 default:
694 reg = (void *)&newregs.regs[idx];
695 }
696
697 ret = copy_from_user(reg, ubuf, sizeof(compat_ulong_t));
698
699 if (ret)
700 goto out;
701 else
702 ubuf += sizeof(compat_ulong_t);
703 }
704
705 if (valid_user_regs(&newregs.user_regs))
706 *task_pt_regs(target) = newregs;
707 else
708 ret = -EINVAL;
709
710out:
711 return ret;
712}
713
714static int compat_vfp_get(struct task_struct *target,
715 const struct user_regset *regset,
716 unsigned int pos, unsigned int count,
717 void *kbuf, void __user *ubuf)
718{
719 struct user_fpsimd_state *uregs;
720 compat_ulong_t fpscr;
721 int ret;
722
723 uregs = &target->thread.fpsimd_state.user_fpsimd;
724
725 /*
726 * The VFP registers are packed into the fpsimd_state, so they all sit
727 * nicely together for us. We just need to create the fpscr separately.
728 */
729 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0,
730 VFP_STATE_SIZE - sizeof(compat_ulong_t));
731
732 if (count && !ret) {
733 fpscr = (uregs->fpsr & VFP_FPSCR_STAT_MASK) |
734 (uregs->fpcr & VFP_FPSCR_CTRL_MASK);
735 ret = put_user(fpscr, (compat_ulong_t *)ubuf);
736 }
737
738 return ret;
739}
740
741static int compat_vfp_set(struct task_struct *target,
742 const struct user_regset *regset,
743 unsigned int pos, unsigned int count,
744 const void *kbuf, const void __user *ubuf)
745{
746 struct user_fpsimd_state *uregs;
747 compat_ulong_t fpscr;
748 int ret;
749
750 if (pos + count > VFP_STATE_SIZE)
751 return -EIO;
752
753 uregs = &target->thread.fpsimd_state.user_fpsimd;
754
755 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
756 VFP_STATE_SIZE - sizeof(compat_ulong_t));
757
758 if (count && !ret) {
759 ret = get_user(fpscr, (compat_ulong_t *)ubuf);
760 uregs->fpsr = fpscr & VFP_FPSCR_STAT_MASK;
761 uregs->fpcr = fpscr & VFP_FPSCR_CTRL_MASK;
762 }
763
764 return ret;
765}
766
767static const struct user_regset aarch32_regsets[] = {
768 [REGSET_COMPAT_GPR] = {
769 .core_note_type = NT_PRSTATUS,
770 .n = COMPAT_ELF_NGREG,
771 .size = sizeof(compat_elf_greg_t),
772 .align = sizeof(compat_elf_greg_t),
773 .get = compat_gpr_get,
774 .set = compat_gpr_set
775 },
776 [REGSET_COMPAT_VFP] = {
777 .core_note_type = NT_ARM_VFP,
778 .n = VFP_STATE_SIZE / sizeof(compat_ulong_t),
779 .size = sizeof(compat_ulong_t),
780 .align = sizeof(compat_ulong_t),
781 .get = compat_vfp_get,
782 .set = compat_vfp_set
783 },
784};
785
786static const struct user_regset_view user_aarch32_view = {
787 .name = "aarch32", .e_machine = EM_ARM,
788 .regsets = aarch32_regsets, .n = ARRAY_SIZE(aarch32_regsets)
789};
790
791int aarch32_break_trap(struct pt_regs *regs)
792{
793 unsigned int instr;
794 bool bp = false;
795 void __user *pc = (void __user *)instruction_pointer(regs);
796
797 if (compat_thumb_mode(regs)) {
798 /* get 16-bit Thumb instruction */
799 get_user(instr, (u16 __user *)pc);
800 if (instr == AARCH32_BREAK_THUMB2_LO) {
801 /* get second half of 32-bit Thumb-2 instruction */
802 get_user(instr, (u16 __user *)(pc + 2));
803 bp = instr == AARCH32_BREAK_THUMB2_HI;
804 } else {
805 bp = instr == AARCH32_BREAK_THUMB;
806 }
807 } else {
808 /* 32-bit ARM instruction */
809 get_user(instr, (u32 __user *)pc);
810 bp = (instr & ~0xf0000000) == AARCH32_BREAK_ARM;
811 }
812
813 if (bp)
814 return ptrace_break(regs);
815 return 1;
816}
817
818static int compat_ptrace_read_user(struct task_struct *tsk, compat_ulong_t off,
819 compat_ulong_t __user *ret)
820{
821 compat_ulong_t tmp;
822
823 if (off & 3)
824 return -EIO;
825
826 if (off == PT_TEXT_ADDR)
827 tmp = tsk->mm->start_code;
828 else if (off == PT_DATA_ADDR)
829 tmp = tsk->mm->start_data;
830 else if (off == PT_TEXT_END_ADDR)
831 tmp = tsk->mm->end_code;
832 else if (off < sizeof(compat_elf_gregset_t))
833 return copy_regset_to_user(tsk, &user_aarch32_view,
834 REGSET_COMPAT_GPR, off,
835 sizeof(compat_ulong_t), ret);
836 else if (off >= COMPAT_USER_SZ)
837 return -EIO;
838 else
839 tmp = 0;
840
841 return put_user(tmp, ret);
842}
843
844static int compat_ptrace_write_user(struct task_struct *tsk, compat_ulong_t off,
845 compat_ulong_t val)
846{
847 int ret;
848
849 if (off & 3 || off >= COMPAT_USER_SZ)
850 return -EIO;
851
852 if (off >= sizeof(compat_elf_gregset_t))
853 return 0;
854
855 ret = copy_regset_from_user(tsk, &user_aarch32_view,
856 REGSET_COMPAT_GPR, off,
857 sizeof(compat_ulong_t),
858 &val);
859 return ret;
860}
861
862#ifdef CONFIG_HAVE_HW_BREAKPOINT
863
864/*
865 * Convert a virtual register number into an index for a thread_info
866 * breakpoint array. Breakpoints are identified using positive numbers
867 * whilst watchpoints are negative. The registers are laid out as pairs
868 * of (address, control), each pair mapping to a unique hw_breakpoint struct.
869 * Register 0 is reserved for describing resource information.
870 */
871static int compat_ptrace_hbp_num_to_idx(compat_long_t num)
872{
873 return (abs(num) - 1) >> 1;
874}
875
876static int compat_ptrace_hbp_get_resource_info(u32 *kdata)
877{
878 u8 num_brps, num_wrps, debug_arch, wp_len;
879 u32 reg = 0;
880
881 num_brps = hw_breakpoint_slots(TYPE_INST);
882 num_wrps = hw_breakpoint_slots(TYPE_DATA);
883
884 debug_arch = debug_monitors_arch();
885 wp_len = 8;
886 reg |= debug_arch;
887 reg <<= 8;
888 reg |= wp_len;
889 reg <<= 8;
890 reg |= num_wrps;
891 reg <<= 8;
892 reg |= num_brps;
893
894 *kdata = reg;
895 return 0;
896}
897
898static int compat_ptrace_hbp_get(unsigned int note_type,
899 struct task_struct *tsk,
900 compat_long_t num,
901 u32 *kdata)
902{
903 u64 addr = 0;
904 u32 ctrl = 0;
905
906 int err, idx = compat_ptrace_hbp_num_to_idx(num);;
907
908 if (num & 1) {
909 err = ptrace_hbp_get_addr(note_type, tsk, idx, &addr);
910 *kdata = (u32)addr;
911 } else {
912 err = ptrace_hbp_get_ctrl(note_type, tsk, idx, &ctrl);
913 *kdata = ctrl;
914 }
915
916 return err;
917}
918
919static int compat_ptrace_hbp_set(unsigned int note_type,
920 struct task_struct *tsk,
921 compat_long_t num,
922 u32 *kdata)
923{
924 u64 addr;
925 u32 ctrl;
926
927 int err, idx = compat_ptrace_hbp_num_to_idx(num);
928
929 if (num & 1) {
930 addr = *kdata;
931 err = ptrace_hbp_set_addr(note_type, tsk, idx, addr);
932 } else {
933 ctrl = *kdata;
934 err = ptrace_hbp_set_ctrl(note_type, tsk, idx, ctrl);
935 }
936
937 return err;
938}
939
940static int compat_ptrace_gethbpregs(struct task_struct *tsk, compat_long_t num,
941 compat_ulong_t __user *data)
942{
943 int ret;
944 u32 kdata;
945 mm_segment_t old_fs = get_fs();
946
947 set_fs(KERNEL_DS);
948 /* Watchpoint */
949 if (num < 0) {
950 ret = compat_ptrace_hbp_get(NT_ARM_HW_WATCH, tsk, num, &kdata);
951 /* Resource info */
952 } else if (num == 0) {
953 ret = compat_ptrace_hbp_get_resource_info(&kdata);
954 /* Breakpoint */
955 } else {
956 ret = compat_ptrace_hbp_get(NT_ARM_HW_BREAK, tsk, num, &kdata);
957 }
958 set_fs(old_fs);
959
960 if (!ret)
961 ret = put_user(kdata, data);
962
963 return ret;
964}
965
966static int compat_ptrace_sethbpregs(struct task_struct *tsk, compat_long_t num,
967 compat_ulong_t __user *data)
968{
969 int ret;
970 u32 kdata = 0;
971 mm_segment_t old_fs = get_fs();
972
973 if (num == 0)
974 return 0;
975
976 ret = get_user(kdata, data);
977 if (ret)
978 return ret;
979
980 set_fs(KERNEL_DS);
981 if (num < 0)
982 ret = compat_ptrace_hbp_set(NT_ARM_HW_WATCH, tsk, num, &kdata);
983 else
984 ret = compat_ptrace_hbp_set(NT_ARM_HW_BREAK, tsk, num, &kdata);
985 set_fs(old_fs);
986
987 return ret;
988}
989#endif /* CONFIG_HAVE_HW_BREAKPOINT */
990
991long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
992 compat_ulong_t caddr, compat_ulong_t cdata)
993{
994 unsigned long addr = caddr;
995 unsigned long data = cdata;
996 void __user *datap = compat_ptr(data);
997 int ret;
998
999 switch (request) {
1000 case PTRACE_PEEKUSR:
1001 ret = compat_ptrace_read_user(child, addr, datap);
1002 break;
1003
1004 case PTRACE_POKEUSR:
1005 ret = compat_ptrace_write_user(child, addr, data);
1006 break;
1007
1008 case COMPAT_PTRACE_GETREGS:
1009 ret = copy_regset_to_user(child,
1010 &user_aarch32_view,
1011 REGSET_COMPAT_GPR,
1012 0, sizeof(compat_elf_gregset_t),
1013 datap);
1014 break;
1015
1016 case COMPAT_PTRACE_SETREGS:
1017 ret = copy_regset_from_user(child,
1018 &user_aarch32_view,
1019 REGSET_COMPAT_GPR,
1020 0, sizeof(compat_elf_gregset_t),
1021 datap);
1022 break;
1023
1024 case COMPAT_PTRACE_GET_THREAD_AREA:
1025 ret = put_user((compat_ulong_t)child->thread.tp_value,
1026 (compat_ulong_t __user *)datap);
1027 break;
1028
1029 case COMPAT_PTRACE_SET_SYSCALL:
1030 task_pt_regs(child)->syscallno = data;
1031 ret = 0;
1032 break;
1033
1034 case COMPAT_PTRACE_GETVFPREGS:
1035 ret = copy_regset_to_user(child,
1036 &user_aarch32_view,
1037 REGSET_COMPAT_VFP,
1038 0, VFP_STATE_SIZE,
1039 datap);
1040 break;
1041
1042 case COMPAT_PTRACE_SETVFPREGS:
1043 ret = copy_regset_from_user(child,
1044 &user_aarch32_view,
1045 REGSET_COMPAT_VFP,
1046 0, VFP_STATE_SIZE,
1047 datap);
1048 break;
1049
1050#ifdef CONFIG_HAVE_HW_BREAKPOINT
1051 case COMPAT_PTRACE_GETHBPREGS:
1052 ret = compat_ptrace_gethbpregs(child, addr, datap);
1053 break;
1054
1055 case COMPAT_PTRACE_SETHBPREGS:
1056 ret = compat_ptrace_sethbpregs(child, addr, datap);
1057 break;
1058#endif
1059
1060 default:
1061 ret = compat_ptrace_request(child, request, addr,
1062 data);
1063 break;
1064 }
1065
1066 return ret;
1067}
1068#endif /* CONFIG_COMPAT */
1069
1070const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1071{
1072#ifdef CONFIG_COMPAT
1073 if (is_compat_thread(task_thread_info(task)))
1074 return &user_aarch32_view;
1075#endif
1076 return &user_aarch64_view;
1077}
1078
1079long arch_ptrace(struct task_struct *child, long request,
1080 unsigned long addr, unsigned long data)
1081{
1082 return ptrace_request(child, request, addr, data);
1083}
1084
1085
1086static int __init ptrace_break_init(void)
1087{
1088 hook_debug_fault_code(DBG_ESR_EVT_BRK, arm64_break_trap, SIGTRAP,
1089 TRAP_BRKPT, "ptrace BRK handler");
1090 return 0;
1091}
1092core_initcall(ptrace_break_init);
1093
1094
1095asmlinkage int syscall_trace(int dir, struct pt_regs *regs)
1096{
1097 unsigned long saved_reg;
1098
1099 if (!test_thread_flag(TIF_SYSCALL_TRACE))
1100 return regs->syscallno;
1101
1102 if (is_compat_task()) {
1103 /* AArch32 uses ip (r12) for scratch */
1104 saved_reg = regs->regs[12];
1105 regs->regs[12] = dir;
1106 } else {
1107 /*
1108 * Save X7. X7 is used to denote syscall entry/exit:
1109 * X7 = 0 -> entry, = 1 -> exit
1110 */
1111 saved_reg = regs->regs[7];
1112 regs->regs[7] = dir;
1113 }
1114
1115 if (dir)
1116 tracehook_report_syscall_exit(regs, 0);
1117 else if (tracehook_report_syscall_entry(regs))
1118 regs->syscallno = ~0UL;
1119
1120 if (is_compat_task())
1121 regs->regs[12] = saved_reg;
1122 else
1123 regs->regs[7] = saved_reg;
1124
1125 return regs->syscallno;
1126}
generated by cgit v1.2.2 (git 2.25.0) at 2026-01-07 08:35:09 -0500