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030c1d5aa46ddadc3c25af32a1052eb304f0287a
[deliverable/linux.git] / arch / arm64 / kernel / ptrace.c
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/audit.h>
23 #include <linux/compat.h>
24 #include <linux/kernel.h>
25 #include <linux/sched.h>
26 #include <linux/mm.h>
27 #include <linux/smp.h>
28 #include <linux/ptrace.h>
29 #include <linux/user.h>
30 #include <linux/seccomp.h>
31 #include <linux/security.h>
32 #include <linux/init.h>
33 #include <linux/signal.h>
34 #include <linux/uaccess.h>
35 #include <linux/perf_event.h>
36 #include <linux/hw_breakpoint.h>
37 #include <linux/regset.h>
38 #include <linux/tracehook.h>
39 #include <linux/elf.h>
40
41 #include <asm/compat.h>
42 #include <asm/debug-monitors.h>
43 #include <asm/pgtable.h>
44 #include <asm/syscall.h>
45 #include <asm/traps.h>
46 #include <asm/system_misc.h>
47
48 #define CREATE_TRACE_POINTS
49 #include <trace/events/syscalls.h>
50
51 struct pt_regs_offset {
52 const char *name;
53 int offset;
54 };
55
56 #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
57 #define REG_OFFSET_END {.name = NULL, .offset = 0}
58 #define GPR_OFFSET_NAME(r) \
59 {.name = "x" #r, .offset = offsetof(struct pt_regs, regs[r])}
60
61 static const struct pt_regs_offset regoffset_table[] = {
62 GPR_OFFSET_NAME(0),
63 GPR_OFFSET_NAME(1),
64 GPR_OFFSET_NAME(2),
65 GPR_OFFSET_NAME(3),
66 GPR_OFFSET_NAME(4),
67 GPR_OFFSET_NAME(5),
68 GPR_OFFSET_NAME(6),
69 GPR_OFFSET_NAME(7),
70 GPR_OFFSET_NAME(8),
71 GPR_OFFSET_NAME(9),
72 GPR_OFFSET_NAME(10),
73 GPR_OFFSET_NAME(11),
74 GPR_OFFSET_NAME(12),
75 GPR_OFFSET_NAME(13),
76 GPR_OFFSET_NAME(14),
77 GPR_OFFSET_NAME(15),
78 GPR_OFFSET_NAME(16),
79 GPR_OFFSET_NAME(17),
80 GPR_OFFSET_NAME(18),
81 GPR_OFFSET_NAME(19),
82 GPR_OFFSET_NAME(20),
83 GPR_OFFSET_NAME(21),
84 GPR_OFFSET_NAME(22),
85 GPR_OFFSET_NAME(23),
86 GPR_OFFSET_NAME(24),
87 GPR_OFFSET_NAME(25),
88 GPR_OFFSET_NAME(26),
89 GPR_OFFSET_NAME(27),
90 GPR_OFFSET_NAME(28),
91 GPR_OFFSET_NAME(29),
92 GPR_OFFSET_NAME(30),
93 {.name = "lr", .offset = offsetof(struct pt_regs, regs[30])},
94 REG_OFFSET_NAME(sp),
95 REG_OFFSET_NAME(pc),
96 REG_OFFSET_NAME(pstate),
97 REG_OFFSET_END,
98 };
99
100 /**
101 * regs_query_register_offset() - query register offset from its name
102 * @name: the name of a register
103 *
104 * regs_query_register_offset() returns the offset of a register in struct
105 * pt_regs from its name. If the name is invalid, this returns -EINVAL;
106 */
107 int regs_query_register_offset(const char *name)
108 {
109 const struct pt_regs_offset *roff;
110
111 for (roff = regoffset_table; roff->name != NULL; roff++)
112 if (!strcmp(roff->name, name))
113 return roff->offset;
114 return -EINVAL;
115 }
116
117 /**
118 * regs_within_kernel_stack() - check the address in the stack
119 * @regs: pt_regs which contains kernel stack pointer.
120 * @addr: address which is checked.
121 *
122 * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
123 * If @addr is within the kernel stack, it returns true. If not, returns false.
124 */
125 static bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
126 {
127 return ((addr & ~(THREAD_SIZE - 1)) ==
128 (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1))) ||
129 on_irq_stack(addr, raw_smp_processor_id());
130 }
131
132 /**
133 * regs_get_kernel_stack_nth() - get Nth entry of the stack
134 * @regs: pt_regs which contains kernel stack pointer.
135 * @n: stack entry number.
136 *
137 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
138 * is specified by @regs. If the @n th entry is NOT in the kernel stack,
139 * this returns 0.
140 */
141 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
142 {
143 unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
144
145 addr += n;
146 if (regs_within_kernel_stack(regs, (unsigned long)addr))
147 return *addr;
148 else
149 return 0;
150 }
151
152 /*
153 * TODO: does not yet catch signals sent when the child dies.
154 * in exit.c or in signal.c.
155 */
156
157 /*
158 * Called by kernel/ptrace.c when detaching..
159 */
160 void ptrace_disable(struct task_struct *child)
161 {
162 /*
163 * This would be better off in core code, but PTRACE_DETACH has
164 * grown its fair share of arch-specific worts and changing it
165 * is likely to cause regressions on obscure architectures.
166 */
167 user_disable_single_step(child);
168 }
169
170 #ifdef CONFIG_HAVE_HW_BREAKPOINT
171 /*
172 * Handle hitting a HW-breakpoint.
173 */
174 static void ptrace_hbptriggered(struct perf_event *bp,
175 struct perf_sample_data *data,
176 struct pt_regs *regs)
177 {
178 struct arch_hw_breakpoint *bkpt = counter_arch_bp(bp);
179 siginfo_t info = {
180 .si_signo = SIGTRAP,
181 .si_errno = 0,
182 .si_code = TRAP_HWBKPT,
183 .si_addr = (void __user *)(bkpt->trigger),
184 };
185
186 #ifdef CONFIG_COMPAT
187 int i;
188
189 if (!is_compat_task())
190 goto send_sig;
191
192 for (i = 0; i < ARM_MAX_BRP; ++i) {
193 if (current->thread.debug.hbp_break[i] == bp) {
194 info.si_errno = (i << 1) + 1;
195 break;
196 }
197 }
198
199 for (i = 0; i < ARM_MAX_WRP; ++i) {
200 if (current->thread.debug.hbp_watch[i] == bp) {
201 info.si_errno = -((i << 1) + 1);
202 break;
203 }
204 }
205
206 send_sig:
207 #endif
208 force_sig_info(SIGTRAP, &info, current);
209 }
210
211 /*
212 * Unregister breakpoints from this task and reset the pointers in
213 * the thread_struct.
214 */
215 void flush_ptrace_hw_breakpoint(struct task_struct *tsk)
216 {
217 int i;
218 struct thread_struct *t = &tsk->thread;
219
220 for (i = 0; i < ARM_MAX_BRP; i++) {
221 if (t->debug.hbp_break[i]) {
222 unregister_hw_breakpoint(t->debug.hbp_break[i]);
223 t->debug.hbp_break[i] = NULL;
224 }
225 }
226
227 for (i = 0; i < ARM_MAX_WRP; i++) {
228 if (t->debug.hbp_watch[i]) {
229 unregister_hw_breakpoint(t->debug.hbp_watch[i]);
230 t->debug.hbp_watch[i] = NULL;
231 }
232 }
233 }
234
235 void ptrace_hw_copy_thread(struct task_struct *tsk)
236 {
237 memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
238 }
239
240 static struct perf_event *ptrace_hbp_get_event(unsigned int note_type,
241 struct task_struct *tsk,
242 unsigned long idx)
243 {
244 struct perf_event *bp = ERR_PTR(-EINVAL);
245
246 switch (note_type) {
247 case NT_ARM_HW_BREAK:
248 if (idx < ARM_MAX_BRP)
249 bp = tsk->thread.debug.hbp_break[idx];
250 break;
251 case NT_ARM_HW_WATCH:
252 if (idx < ARM_MAX_WRP)
253 bp = tsk->thread.debug.hbp_watch[idx];
254 break;
255 }
256
257 return bp;
258 }
259
260 static int ptrace_hbp_set_event(unsigned int note_type,
261 struct task_struct *tsk,
262 unsigned long idx,
263 struct perf_event *bp)
264 {
265 int err = -EINVAL;
266
267 switch (note_type) {
268 case NT_ARM_HW_BREAK:
269 if (idx < ARM_MAX_BRP) {
270 tsk->thread.debug.hbp_break[idx] = bp;
271 err = 0;
272 }
273 break;
274 case NT_ARM_HW_WATCH:
275 if (idx < ARM_MAX_WRP) {
276 tsk->thread.debug.hbp_watch[idx] = bp;
277 err = 0;
278 }
279 break;
280 }
281
282 return err;
283 }
284
285 static struct perf_event *ptrace_hbp_create(unsigned int note_type,
286 struct task_struct *tsk,
287 unsigned long idx)
288 {
289 struct perf_event *bp;
290 struct perf_event_attr attr;
291 int err, type;
292
293 switch (note_type) {
294 case NT_ARM_HW_BREAK:
295 type = HW_BREAKPOINT_X;
296 break;
297 case NT_ARM_HW_WATCH:
298 type = HW_BREAKPOINT_RW;
299 break;
300 default:
301 return ERR_PTR(-EINVAL);
302 }
303
304 ptrace_breakpoint_init(&attr);
305
306 /*
307 * Initialise fields to sane defaults
308 * (i.e. values that will pass validation).
309 */
310 attr.bp_addr = 0;
311 attr.bp_len = HW_BREAKPOINT_LEN_4;
312 attr.bp_type = type;
313 attr.disabled = 1;
314
315 bp = register_user_hw_breakpoint(&attr, ptrace_hbptriggered, NULL, tsk);
316 if (IS_ERR(bp))
317 return bp;
318
319 err = ptrace_hbp_set_event(note_type, tsk, idx, bp);
320 if (err)
321 return ERR_PTR(err);
322
323 return bp;
324 }
325
326 static int ptrace_hbp_fill_attr_ctrl(unsigned int note_type,
327 struct arch_hw_breakpoint_ctrl ctrl,
328 struct perf_event_attr *attr)
329 {
330 int err, len, type, disabled = !ctrl.enabled;
331
332 attr->disabled = disabled;
333 if (disabled)
334 return 0;
335
336 err = arch_bp_generic_fields(ctrl, &len, &type);
337 if (err)
338 return err;
339
340 switch (note_type) {
341 case NT_ARM_HW_BREAK:
342 if ((type & HW_BREAKPOINT_X) != type)
343 return -EINVAL;
344 break;
345 case NT_ARM_HW_WATCH:
346 if ((type & HW_BREAKPOINT_RW) != type)
347 return -EINVAL;
348 break;
349 default:
350 return -EINVAL;
351 }
352
353 attr->bp_len = len;
354 attr->bp_type = type;
355
356 return 0;
357 }
358
359 static int ptrace_hbp_get_resource_info(unsigned int note_type, u32 *info)
360 {
361 u8 num;
362 u32 reg = 0;
363
364 switch (note_type) {
365 case NT_ARM_HW_BREAK:
366 num = hw_breakpoint_slots(TYPE_INST);
367 break;
368 case NT_ARM_HW_WATCH:
369 num = hw_breakpoint_slots(TYPE_DATA);
370 break;
371 default:
372 return -EINVAL;
373 }
374
375 reg |= debug_monitors_arch();
376 reg <<= 8;
377 reg |= num;
378
379 *info = reg;
380 return 0;
381 }
382
383 static int ptrace_hbp_get_ctrl(unsigned int note_type,
384 struct task_struct *tsk,
385 unsigned long idx,
386 u32 *ctrl)
387 {
388 struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
389
390 if (IS_ERR(bp))
391 return PTR_ERR(bp);
392
393 *ctrl = bp ? encode_ctrl_reg(counter_arch_bp(bp)->ctrl) : 0;
394 return 0;
395 }
396
397 static int ptrace_hbp_get_addr(unsigned int note_type,
398 struct task_struct *tsk,
399 unsigned long idx,
400 u64 *addr)
401 {
402 struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
403
404 if (IS_ERR(bp))
405 return PTR_ERR(bp);
406
407 *addr = bp ? bp->attr.bp_addr : 0;
408 return 0;
409 }
410
411 static struct perf_event *ptrace_hbp_get_initialised_bp(unsigned int note_type,
412 struct task_struct *tsk,
413 unsigned long idx)
414 {
415 struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
416
417 if (!bp)
418 bp = ptrace_hbp_create(note_type, tsk, idx);
419
420 return bp;
421 }
422
423 static int ptrace_hbp_set_ctrl(unsigned int note_type,
424 struct task_struct *tsk,
425 unsigned long idx,
426 u32 uctrl)
427 {
428 int err;
429 struct perf_event *bp;
430 struct perf_event_attr attr;
431 struct arch_hw_breakpoint_ctrl ctrl;
432
433 bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx);
434 if (IS_ERR(bp)) {
435 err = PTR_ERR(bp);
436 return err;
437 }
438
439 attr = bp->attr;
440 decode_ctrl_reg(uctrl, &ctrl);
441 err = ptrace_hbp_fill_attr_ctrl(note_type, ctrl, &attr);
442 if (err)
443 return err;
444
445 return modify_user_hw_breakpoint(bp, &attr);
446 }
447
448 static int ptrace_hbp_set_addr(unsigned int note_type,
449 struct task_struct *tsk,
450 unsigned long idx,
451 u64 addr)
452 {
453 int err;
454 struct perf_event *bp;
455 struct perf_event_attr attr;
456
457 bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx);
458 if (IS_ERR(bp)) {
459 err = PTR_ERR(bp);
460 return err;
461 }
462
463 attr = bp->attr;
464 attr.bp_addr = addr;
465 err = modify_user_hw_breakpoint(bp, &attr);
466 return err;
467 }
468
469 #define PTRACE_HBP_ADDR_SZ sizeof(u64)
470 #define PTRACE_HBP_CTRL_SZ sizeof(u32)
471 #define PTRACE_HBP_PAD_SZ sizeof(u32)
472
473 static int hw_break_get(struct task_struct *target,
474 const struct user_regset *regset,
475 unsigned int pos, unsigned int count,
476 void *kbuf, void __user *ubuf)
477 {
478 unsigned int note_type = regset->core_note_type;
479 int ret, idx = 0, offset, limit;
480 u32 info, ctrl;
481 u64 addr;
482
483 /* Resource info */
484 ret = ptrace_hbp_get_resource_info(note_type, &info);
485 if (ret)
486 return ret;
487
488 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &info, 0,
489 sizeof(info));
490 if (ret)
491 return ret;
492
493 /* Pad */
494 offset = offsetof(struct user_hwdebug_state, pad);
495 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, offset,
496 offset + PTRACE_HBP_PAD_SZ);
497 if (ret)
498 return ret;
499
500 /* (address, ctrl) registers */
501 offset = offsetof(struct user_hwdebug_state, dbg_regs);
502 limit = regset->n * regset->size;
503 while (count && offset < limit) {
504 ret = ptrace_hbp_get_addr(note_type, target, idx, &addr);
505 if (ret)
506 return ret;
507 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &addr,
508 offset, offset + PTRACE_HBP_ADDR_SZ);
509 if (ret)
510 return ret;
511 offset += PTRACE_HBP_ADDR_SZ;
512
513 ret = ptrace_hbp_get_ctrl(note_type, target, idx, &ctrl);
514 if (ret)
515 return ret;
516 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &ctrl,
517 offset, offset + PTRACE_HBP_CTRL_SZ);
518 if (ret)
519 return ret;
520 offset += PTRACE_HBP_CTRL_SZ;
521
522 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
523 offset,
524 offset + PTRACE_HBP_PAD_SZ);
525 if (ret)
526 return ret;
527 offset += PTRACE_HBP_PAD_SZ;
528 idx++;
529 }
530
531 return 0;
532 }
533
534 static int hw_break_set(struct task_struct *target,
535 const struct user_regset *regset,
536 unsigned int pos, unsigned int count,
537 const void *kbuf, const void __user *ubuf)
538 {
539 unsigned int note_type = regset->core_note_type;
540 int ret, idx = 0, offset, limit;
541 u32 ctrl;
542 u64 addr;
543
544 /* Resource info and pad */
545 offset = offsetof(struct user_hwdebug_state, dbg_regs);
546 ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, offset);
547 if (ret)
548 return ret;
549
550 /* (address, ctrl) registers */
551 limit = regset->n * regset->size;
552 while (count && offset < limit) {
553 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &addr,
554 offset, offset + PTRACE_HBP_ADDR_SZ);
555 if (ret)
556 return ret;
557 ret = ptrace_hbp_set_addr(note_type, target, idx, addr);
558 if (ret)
559 return ret;
560 offset += PTRACE_HBP_ADDR_SZ;
561
562 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl,
563 offset, offset + PTRACE_HBP_CTRL_SZ);
564 if (ret)
565 return ret;
566 ret = ptrace_hbp_set_ctrl(note_type, target, idx, ctrl);
567 if (ret)
568 return ret;
569 offset += PTRACE_HBP_CTRL_SZ;
570
571 ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
572 offset,
573 offset + PTRACE_HBP_PAD_SZ);
574 if (ret)
575 return ret;
576 offset += PTRACE_HBP_PAD_SZ;
577 idx++;
578 }
579
580 return 0;
581 }
582 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
583
584 static int gpr_get(struct task_struct *target,
585 const struct user_regset *regset,
586 unsigned int pos, unsigned int count,
587 void *kbuf, void __user *ubuf)
588 {
589 struct user_pt_regs *uregs = &task_pt_regs(target)->user_regs;
590 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0, -1);
591 }
592
593 static int gpr_set(struct task_struct *target, const struct user_regset *regset,
594 unsigned int pos, unsigned int count,
595 const void *kbuf, const void __user *ubuf)
596 {
597 int ret;
598 struct user_pt_regs newregs;
599
600 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newregs, 0, -1);
601 if (ret)
602 return ret;
603
604 if (!valid_user_regs(&newregs, target))
605 return -EINVAL;
606
607 task_pt_regs(target)->user_regs = newregs;
608 return 0;
609 }
610
611 /*
612 * TODO: update fp accessors for lazy context switching (sync/flush hwstate)
613 */
614 static int fpr_get(struct task_struct *target, const struct user_regset *regset,
615 unsigned int pos, unsigned int count,
616 void *kbuf, void __user *ubuf)
617 {
618 struct user_fpsimd_state *uregs;
619 uregs = &target->thread.fpsimd_state.user_fpsimd;
620 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0, -1);
621 }
622
623 static int fpr_set(struct task_struct *target, const struct user_regset *regset,
624 unsigned int pos, unsigned int count,
625 const void *kbuf, const void __user *ubuf)
626 {
627 int ret;
628 struct user_fpsimd_state newstate;
629
630 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newstate, 0, -1);
631 if (ret)
632 return ret;
633
634 target->thread.fpsimd_state.user_fpsimd = newstate;
635 fpsimd_flush_task_state(target);
636 return ret;
637 }
638
639 static int tls_get(struct task_struct *target, const struct user_regset *regset,
640 unsigned int pos, unsigned int count,
641 void *kbuf, void __user *ubuf)
642 {
643 unsigned long *tls = &target->thread.tp_value;
644 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, tls, 0, -1);
645 }
646
647 static int tls_set(struct task_struct *target, const struct user_regset *regset,
648 unsigned int pos, unsigned int count,
649 const void *kbuf, const void __user *ubuf)
650 {
651 int ret;
652 unsigned long tls;
653
654 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tls, 0, -1);
655 if (ret)
656 return ret;
657
658 target->thread.tp_value = tls;
659 return ret;
660 }
661
662 static int system_call_get(struct task_struct *target,
663 const struct user_regset *regset,
664 unsigned int pos, unsigned int count,
665 void *kbuf, void __user *ubuf)
666 {
667 int syscallno = task_pt_regs(target)->syscallno;
668
669 return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
670 &syscallno, 0, -1);
671 }
672
673 static int system_call_set(struct task_struct *target,
674 const struct user_regset *regset,
675 unsigned int pos, unsigned int count,
676 const void *kbuf, const void __user *ubuf)
677 {
678 int syscallno, ret;
679
680 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &syscallno, 0, -1);
681 if (ret)
682 return ret;
683
684 task_pt_regs(target)->syscallno = syscallno;
685 return ret;
686 }
687
688 enum aarch64_regset {
689 REGSET_GPR,
690 REGSET_FPR,
691 REGSET_TLS,
692 #ifdef CONFIG_HAVE_HW_BREAKPOINT
693 REGSET_HW_BREAK,
694 REGSET_HW_WATCH,
695 #endif
696 REGSET_SYSTEM_CALL,
697 };
698
699 static const struct user_regset aarch64_regsets[] = {
700 [REGSET_GPR] = {
701 .core_note_type = NT_PRSTATUS,
702 .n = sizeof(struct user_pt_regs) / sizeof(u64),
703 .size = sizeof(u64),
704 .align = sizeof(u64),
705 .get = gpr_get,
706 .set = gpr_set
707 },
708 [REGSET_FPR] = {
709 .core_note_type = NT_PRFPREG,
710 .n = sizeof(struct user_fpsimd_state) / sizeof(u32),
711 /*
712 * We pretend we have 32-bit registers because the fpsr and
713 * fpcr are 32-bits wide.
714 */
715 .size = sizeof(u32),
716 .align = sizeof(u32),
717 .get = fpr_get,
718 .set = fpr_set
719 },
720 [REGSET_TLS] = {
721 .core_note_type = NT_ARM_TLS,
722 .n = 1,
723 .size = sizeof(void *),
724 .align = sizeof(void *),
725 .get = tls_get,
726 .set = tls_set,
727 },
728 #ifdef CONFIG_HAVE_HW_BREAKPOINT
729 [REGSET_HW_BREAK] = {
730 .core_note_type = NT_ARM_HW_BREAK,
731 .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
732 .size = sizeof(u32),
733 .align = sizeof(u32),
734 .get = hw_break_get,
735 .set = hw_break_set,
736 },
737 [REGSET_HW_WATCH] = {
738 .core_note_type = NT_ARM_HW_WATCH,
739 .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
740 .size = sizeof(u32),
741 .align = sizeof(u32),
742 .get = hw_break_get,
743 .set = hw_break_set,
744 },
745 #endif
746 [REGSET_SYSTEM_CALL] = {
747 .core_note_type = NT_ARM_SYSTEM_CALL,
748 .n = 1,
749 .size = sizeof(int),
750 .align = sizeof(int),
751 .get = system_call_get,
752 .set = system_call_set,
753 },
754 };
755
756 static const struct user_regset_view user_aarch64_view = {
757 .name = "aarch64", .e_machine = EM_AARCH64,
758 .regsets = aarch64_regsets, .n = ARRAY_SIZE(aarch64_regsets)
759 };
760
761 #ifdef CONFIG_COMPAT
762 #include <linux/compat.h>
763
764 enum compat_regset {
765 REGSET_COMPAT_GPR,
766 REGSET_COMPAT_VFP,
767 };
768
769 static int compat_gpr_get(struct task_struct *target,
770 const struct user_regset *regset,
771 unsigned int pos, unsigned int count,
772 void *kbuf, void __user *ubuf)
773 {
774 int ret = 0;
775 unsigned int i, start, num_regs;
776
777 /* Calculate the number of AArch32 registers contained in count */
778 num_regs = count / regset->size;
779
780 /* Convert pos into an register number */
781 start = pos / regset->size;
782
783 if (start + num_regs > regset->n)
784 return -EIO;
785
786 for (i = 0; i < num_regs; ++i) {
787 unsigned int idx = start + i;
788 compat_ulong_t reg;
789
790 switch (idx) {
791 case 15:
792 reg = task_pt_regs(target)->pc;
793 break;
794 case 16:
795 reg = task_pt_regs(target)->pstate;
796 break;
797 case 17:
798 reg = task_pt_regs(target)->orig_x0;
799 break;
800 default:
801 reg = task_pt_regs(target)->regs[idx];
802 }
803
804 if (kbuf) {
805 memcpy(kbuf, &reg, sizeof(reg));
806 kbuf += sizeof(reg);
807 } else {
808 ret = copy_to_user(ubuf, &reg, sizeof(reg));
809 if (ret) {
810 ret = -EFAULT;
811 break;
812 }
813
814 ubuf += sizeof(reg);
815 }
816 }
817
818 return ret;
819 }
820
821 static int compat_gpr_set(struct task_struct *target,
822 const struct user_regset *regset,
823 unsigned int pos, unsigned int count,
824 const void *kbuf, const void __user *ubuf)
825 {
826 struct pt_regs newregs;
827 int ret = 0;
828 unsigned int i, start, num_regs;
829
830 /* Calculate the number of AArch32 registers contained in count */
831 num_regs = count / regset->size;
832
833 /* Convert pos into an register number */
834 start = pos / regset->size;
835
836 if (start + num_regs > regset->n)
837 return -EIO;
838
839 newregs = *task_pt_regs(target);
840
841 for (i = 0; i < num_regs; ++i) {
842 unsigned int idx = start + i;
843 compat_ulong_t reg;
844
845 if (kbuf) {
846 memcpy(&reg, kbuf, sizeof(reg));
847 kbuf += sizeof(reg);
848 } else {
849 ret = copy_from_user(&reg, ubuf, sizeof(reg));
850 if (ret) {
851 ret = -EFAULT;
852 break;
853 }
854
855 ubuf += sizeof(reg);
856 }
857
858 switch (idx) {
859 case 15:
860 newregs.pc = reg;
861 break;
862 case 16:
863 newregs.pstate = reg;
864 break;
865 case 17:
866 newregs.orig_x0 = reg;
867 break;
868 default:
869 newregs.regs[idx] = reg;
870 }
871
872 }
873
874 if (valid_user_regs(&newregs.user_regs, target))
875 *task_pt_regs(target) = newregs;
876 else
877 ret = -EINVAL;
878
879 return ret;
880 }
881
882 static int compat_vfp_get(struct task_struct *target,
883 const struct user_regset *regset,
884 unsigned int pos, unsigned int count,
885 void *kbuf, void __user *ubuf)
886 {
887 struct user_fpsimd_state *uregs;
888 compat_ulong_t fpscr;
889 int ret;
890
891 uregs = &target->thread.fpsimd_state.user_fpsimd;
892
893 /*
894 * The VFP registers are packed into the fpsimd_state, so they all sit
895 * nicely together for us. We just need to create the fpscr separately.
896 */
897 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0,
898 VFP_STATE_SIZE - sizeof(compat_ulong_t));
899
900 if (count && !ret) {
901 fpscr = (uregs->fpsr & VFP_FPSCR_STAT_MASK) |
902 (uregs->fpcr & VFP_FPSCR_CTRL_MASK);
903 ret = put_user(fpscr, (compat_ulong_t *)ubuf);
904 }
905
906 return ret;
907 }
908
909 static int compat_vfp_set(struct task_struct *target,
910 const struct user_regset *regset,
911 unsigned int pos, unsigned int count,
912 const void *kbuf, const void __user *ubuf)
913 {
914 struct user_fpsimd_state *uregs;
915 compat_ulong_t fpscr;
916 int ret;
917
918 if (pos + count > VFP_STATE_SIZE)
919 return -EIO;
920
921 uregs = &target->thread.fpsimd_state.user_fpsimd;
922
923 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
924 VFP_STATE_SIZE - sizeof(compat_ulong_t));
925
926 if (count && !ret) {
927 ret = get_user(fpscr, (compat_ulong_t *)ubuf);
928 uregs->fpsr = fpscr & VFP_FPSCR_STAT_MASK;
929 uregs->fpcr = fpscr & VFP_FPSCR_CTRL_MASK;
930 }
931
932 fpsimd_flush_task_state(target);
933 return ret;
934 }
935
936 static int compat_tls_get(struct task_struct *target,
937 const struct user_regset *regset, unsigned int pos,
938 unsigned int count, void *kbuf, void __user *ubuf)
939 {
940 compat_ulong_t tls = (compat_ulong_t)target->thread.tp_value;
941 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &tls, 0, -1);
942 }
943
944 static int compat_tls_set(struct task_struct *target,
945 const struct user_regset *regset, unsigned int pos,
946 unsigned int count, const void *kbuf,
947 const void __user *ubuf)
948 {
949 int ret;
950 compat_ulong_t tls;
951
952 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tls, 0, -1);
953 if (ret)
954 return ret;
955
956 target->thread.tp_value = tls;
957 return ret;
958 }
959
960 static const struct user_regset aarch32_regsets[] = {
961 [REGSET_COMPAT_GPR] = {
962 .core_note_type = NT_PRSTATUS,
963 .n = COMPAT_ELF_NGREG,
964 .size = sizeof(compat_elf_greg_t),
965 .align = sizeof(compat_elf_greg_t),
966 .get = compat_gpr_get,
967 .set = compat_gpr_set
968 },
969 [REGSET_COMPAT_VFP] = {
970 .core_note_type = NT_ARM_VFP,
971 .n = VFP_STATE_SIZE / sizeof(compat_ulong_t),
972 .size = sizeof(compat_ulong_t),
973 .align = sizeof(compat_ulong_t),
974 .get = compat_vfp_get,
975 .set = compat_vfp_set
976 },
977 };
978
979 static const struct user_regset_view user_aarch32_view = {
980 .name = "aarch32", .e_machine = EM_ARM,
981 .regsets = aarch32_regsets, .n = ARRAY_SIZE(aarch32_regsets)
982 };
983
984 static const struct user_regset aarch32_ptrace_regsets[] = {
985 [REGSET_GPR] = {
986 .core_note_type = NT_PRSTATUS,
987 .n = COMPAT_ELF_NGREG,
988 .size = sizeof(compat_elf_greg_t),
989 .align = sizeof(compat_elf_greg_t),
990 .get = compat_gpr_get,
991 .set = compat_gpr_set
992 },
993 [REGSET_FPR] = {
994 .core_note_type = NT_ARM_VFP,
995 .n = VFP_STATE_SIZE / sizeof(compat_ulong_t),
996 .size = sizeof(compat_ulong_t),
997 .align = sizeof(compat_ulong_t),
998 .get = compat_vfp_get,
999 .set = compat_vfp_set
1000 },
1001 [REGSET_TLS] = {
1002 .core_note_type = NT_ARM_TLS,
1003 .n = 1,
1004 .size = sizeof(compat_ulong_t),
1005 .align = sizeof(compat_ulong_t),
1006 .get = compat_tls_get,
1007 .set = compat_tls_set,
1008 },
1009 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1010 [REGSET_HW_BREAK] = {
1011 .core_note_type = NT_ARM_HW_BREAK,
1012 .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
1013 .size = sizeof(u32),
1014 .align = sizeof(u32),
1015 .get = hw_break_get,
1016 .set = hw_break_set,
1017 },
1018 [REGSET_HW_WATCH] = {
1019 .core_note_type = NT_ARM_HW_WATCH,
1020 .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
1021 .size = sizeof(u32),
1022 .align = sizeof(u32),
1023 .get = hw_break_get,
1024 .set = hw_break_set,
1025 },
1026 #endif
1027 [REGSET_SYSTEM_CALL] = {
1028 .core_note_type = NT_ARM_SYSTEM_CALL,
1029 .n = 1,
1030 .size = sizeof(int),
1031 .align = sizeof(int),
1032 .get = system_call_get,
1033 .set = system_call_set,
1034 },
1035 };
1036
1037 static const struct user_regset_view user_aarch32_ptrace_view = {
1038 .name = "aarch32", .e_machine = EM_ARM,
1039 .regsets = aarch32_ptrace_regsets, .n = ARRAY_SIZE(aarch32_ptrace_regsets)
1040 };
1041
1042 static int compat_ptrace_read_user(struct task_struct *tsk, compat_ulong_t off,
1043 compat_ulong_t __user *ret)
1044 {
1045 compat_ulong_t tmp;
1046
1047 if (off & 3)
1048 return -EIO;
1049
1050 if (off == COMPAT_PT_TEXT_ADDR)
1051 tmp = tsk->mm->start_code;
1052 else if (off == COMPAT_PT_DATA_ADDR)
1053 tmp = tsk->mm->start_data;
1054 else if (off == COMPAT_PT_TEXT_END_ADDR)
1055 tmp = tsk->mm->end_code;
1056 else if (off < sizeof(compat_elf_gregset_t))
1057 return copy_regset_to_user(tsk, &user_aarch32_view,
1058 REGSET_COMPAT_GPR, off,
1059 sizeof(compat_ulong_t), ret);
1060 else if (off >= COMPAT_USER_SZ)
1061 return -EIO;
1062 else
1063 tmp = 0;
1064
1065 return put_user(tmp, ret);
1066 }
1067
1068 static int compat_ptrace_write_user(struct task_struct *tsk, compat_ulong_t off,
1069 compat_ulong_t val)
1070 {
1071 int ret;
1072 mm_segment_t old_fs = get_fs();
1073
1074 if (off & 3 || off >= COMPAT_USER_SZ)
1075 return -EIO;
1076
1077 if (off >= sizeof(compat_elf_gregset_t))
1078 return 0;
1079
1080 set_fs(KERNEL_DS);
1081 ret = copy_regset_from_user(tsk, &user_aarch32_view,
1082 REGSET_COMPAT_GPR, off,
1083 sizeof(compat_ulong_t),
1084 &val);
1085 set_fs(old_fs);
1086
1087 return ret;
1088 }
1089
1090 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1091
1092 /*
1093 * Convert a virtual register number into an index for a thread_info
1094 * breakpoint array. Breakpoints are identified using positive numbers
1095 * whilst watchpoints are negative. The registers are laid out as pairs
1096 * of (address, control), each pair mapping to a unique hw_breakpoint struct.
1097 * Register 0 is reserved for describing resource information.
1098 */
1099 static int compat_ptrace_hbp_num_to_idx(compat_long_t num)
1100 {
1101 return (abs(num) - 1) >> 1;
1102 }
1103
1104 static int compat_ptrace_hbp_get_resource_info(u32 *kdata)
1105 {
1106 u8 num_brps, num_wrps, debug_arch, wp_len;
1107 u32 reg = 0;
1108
1109 num_brps = hw_breakpoint_slots(TYPE_INST);
1110 num_wrps = hw_breakpoint_slots(TYPE_DATA);
1111
1112 debug_arch = debug_monitors_arch();
1113 wp_len = 8;
1114 reg |= debug_arch;
1115 reg <<= 8;
1116 reg |= wp_len;
1117 reg <<= 8;
1118 reg |= num_wrps;
1119 reg <<= 8;
1120 reg |= num_brps;
1121
1122 *kdata = reg;
1123 return 0;
1124 }
1125
1126 static int compat_ptrace_hbp_get(unsigned int note_type,
1127 struct task_struct *tsk,
1128 compat_long_t num,
1129 u32 *kdata)
1130 {
1131 u64 addr = 0;
1132 u32 ctrl = 0;
1133
1134 int err, idx = compat_ptrace_hbp_num_to_idx(num);;
1135
1136 if (num & 1) {
1137 err = ptrace_hbp_get_addr(note_type, tsk, idx, &addr);
1138 *kdata = (u32)addr;
1139 } else {
1140 err = ptrace_hbp_get_ctrl(note_type, tsk, idx, &ctrl);
1141 *kdata = ctrl;
1142 }
1143
1144 return err;
1145 }
1146
1147 static int compat_ptrace_hbp_set(unsigned int note_type,
1148 struct task_struct *tsk,
1149 compat_long_t num,
1150 u32 *kdata)
1151 {
1152 u64 addr;
1153 u32 ctrl;
1154
1155 int err, idx = compat_ptrace_hbp_num_to_idx(num);
1156
1157 if (num & 1) {
1158 addr = *kdata;
1159 err = ptrace_hbp_set_addr(note_type, tsk, idx, addr);
1160 } else {
1161 ctrl = *kdata;
1162 err = ptrace_hbp_set_ctrl(note_type, tsk, idx, ctrl);
1163 }
1164
1165 return err;
1166 }
1167
1168 static int compat_ptrace_gethbpregs(struct task_struct *tsk, compat_long_t num,
1169 compat_ulong_t __user *data)
1170 {
1171 int ret;
1172 u32 kdata;
1173 mm_segment_t old_fs = get_fs();
1174
1175 set_fs(KERNEL_DS);
1176 /* Watchpoint */
1177 if (num < 0) {
1178 ret = compat_ptrace_hbp_get(NT_ARM_HW_WATCH, tsk, num, &kdata);
1179 /* Resource info */
1180 } else if (num == 0) {
1181 ret = compat_ptrace_hbp_get_resource_info(&kdata);
1182 /* Breakpoint */
1183 } else {
1184 ret = compat_ptrace_hbp_get(NT_ARM_HW_BREAK, tsk, num, &kdata);
1185 }
1186 set_fs(old_fs);
1187
1188 if (!ret)
1189 ret = put_user(kdata, data);
1190
1191 return ret;
1192 }
1193
1194 static int compat_ptrace_sethbpregs(struct task_struct *tsk, compat_long_t num,
1195 compat_ulong_t __user *data)
1196 {
1197 int ret;
1198 u32 kdata = 0;
1199 mm_segment_t old_fs = get_fs();
1200
1201 if (num == 0)
1202 return 0;
1203
1204 ret = get_user(kdata, data);
1205 if (ret)
1206 return ret;
1207
1208 set_fs(KERNEL_DS);
1209 if (num < 0)
1210 ret = compat_ptrace_hbp_set(NT_ARM_HW_WATCH, tsk, num, &kdata);
1211 else
1212 ret = compat_ptrace_hbp_set(NT_ARM_HW_BREAK, tsk, num, &kdata);
1213 set_fs(old_fs);
1214
1215 return ret;
1216 }
1217 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
1218
1219 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
1220 compat_ulong_t caddr, compat_ulong_t cdata)
1221 {
1222 unsigned long addr = caddr;
1223 unsigned long data = cdata;
1224 void __user *datap = compat_ptr(data);
1225 int ret;
1226
1227 switch (request) {
1228 case PTRACE_PEEKUSR:
1229 ret = compat_ptrace_read_user(child, addr, datap);
1230 break;
1231
1232 case PTRACE_POKEUSR:
1233 ret = compat_ptrace_write_user(child, addr, data);
1234 break;
1235
1236 case COMPAT_PTRACE_GETREGS:
1237 ret = copy_regset_to_user(child,
1238 &user_aarch32_view,
1239 REGSET_COMPAT_GPR,
1240 0, sizeof(compat_elf_gregset_t),
1241 datap);
1242 break;
1243
1244 case COMPAT_PTRACE_SETREGS:
1245 ret = copy_regset_from_user(child,
1246 &user_aarch32_view,
1247 REGSET_COMPAT_GPR,
1248 0, sizeof(compat_elf_gregset_t),
1249 datap);
1250 break;
1251
1252 case COMPAT_PTRACE_GET_THREAD_AREA:
1253 ret = put_user((compat_ulong_t)child->thread.tp_value,
1254 (compat_ulong_t __user *)datap);
1255 break;
1256
1257 case COMPAT_PTRACE_SET_SYSCALL:
1258 task_pt_regs(child)->syscallno = data;
1259 ret = 0;
1260 break;
1261
1262 case COMPAT_PTRACE_GETVFPREGS:
1263 ret = copy_regset_to_user(child,
1264 &user_aarch32_view,
1265 REGSET_COMPAT_VFP,
1266 0, VFP_STATE_SIZE,
1267 datap);
1268 break;
1269
1270 case COMPAT_PTRACE_SETVFPREGS:
1271 ret = copy_regset_from_user(child,
1272 &user_aarch32_view,
1273 REGSET_COMPAT_VFP,
1274 0, VFP_STATE_SIZE,
1275 datap);
1276 break;
1277
1278 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1279 case COMPAT_PTRACE_GETHBPREGS:
1280 ret = compat_ptrace_gethbpregs(child, addr, datap);
1281 break;
1282
1283 case COMPAT_PTRACE_SETHBPREGS:
1284 ret = compat_ptrace_sethbpregs(child, addr, datap);
1285 break;
1286 #endif
1287
1288 default:
1289 ret = compat_ptrace_request(child, request, addr,
1290 data);
1291 break;
1292 }
1293
1294 return ret;
1295 }
1296 #endif /* CONFIG_COMPAT */
1297
1298 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1299 {
1300 #ifdef CONFIG_COMPAT
1301 /*
1302 * Core dumping of 32-bit tasks or compat ptrace requests must use the
1303 * user_aarch32_view compatible with arm32. Native ptrace requests on
1304 * 32-bit children use an extended user_aarch32_ptrace_view to allow
1305 * access to the TLS register.
1306 */
1307 if (is_compat_task())
1308 return &user_aarch32_view;
1309 else if (is_compat_thread(task_thread_info(task)))
1310 return &user_aarch32_ptrace_view;
1311 #endif
1312 return &user_aarch64_view;
1313 }
1314
1315 long arch_ptrace(struct task_struct *child, long request,
1316 unsigned long addr, unsigned long data)
1317 {
1318 return ptrace_request(child, request, addr, data);
1319 }
1320
1321 enum ptrace_syscall_dir {
1322 PTRACE_SYSCALL_ENTER = 0,
1323 PTRACE_SYSCALL_EXIT,
1324 };
1325
1326 static void tracehook_report_syscall(struct pt_regs *regs,
1327 enum ptrace_syscall_dir dir)
1328 {
1329 int regno;
1330 unsigned long saved_reg;
1331
1332 /*
1333 * A scratch register (ip(r12) on AArch32, x7 on AArch64) is
1334 * used to denote syscall entry/exit:
1335 */
1336 regno = (is_compat_task() ? 12 : 7);
1337 saved_reg = regs->regs[regno];
1338 regs->regs[regno] = dir;
1339
1340 if (dir == PTRACE_SYSCALL_EXIT)
1341 tracehook_report_syscall_exit(regs, 0);
1342 else if (tracehook_report_syscall_entry(regs))
1343 regs->syscallno = ~0UL;
1344
1345 regs->regs[regno] = saved_reg;
1346 }
1347
1348 asmlinkage int syscall_trace_enter(struct pt_regs *regs)
1349 {
1350 /* Do the secure computing check first; failures should be fast. */
1351 if (secure_computing() == -1)
1352 return -1;
1353
1354 if (test_thread_flag(TIF_SYSCALL_TRACE))
1355 tracehook_report_syscall(regs, PTRACE_SYSCALL_ENTER);
1356
1357 if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
1358 trace_sys_enter(regs, regs->syscallno);
1359
1360 audit_syscall_entry(regs->syscallno, regs->orig_x0, regs->regs[1],
1361 regs->regs[2], regs->regs[3]);
1362
1363 return regs->syscallno;
1364 }
1365
1366 asmlinkage void syscall_trace_exit(struct pt_regs *regs)
1367 {
1368 audit_syscall_exit(regs);
1369
1370 if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
1371 trace_sys_exit(regs, regs_return_value(regs));
1372
1373 if (test_thread_flag(TIF_SYSCALL_TRACE))
1374 tracehook_report_syscall(regs, PTRACE_SYSCALL_EXIT);
1375 }
1376
1377 /*
1378 * Bits which are always architecturally RES0 per ARM DDI 0487A.h
1379 * Userspace cannot use these until they have an architectural meaning.
1380 * We also reserve IL for the kernel; SS is handled dynamically.
1381 */
1382 #define SPSR_EL1_AARCH64_RES0_BITS \
1383 (GENMASK_ULL(63,32) | GENMASK_ULL(27, 22) | GENMASK_ULL(20, 10) | \
1384 GENMASK_ULL(5, 5))
1385 #define SPSR_EL1_AARCH32_RES0_BITS \
1386 (GENMASK_ULL(63,32) | GENMASK_ULL(24, 22) | GENMASK_ULL(20,20))
1387
1388 static int valid_compat_regs(struct user_pt_regs *regs)
1389 {
1390 regs->pstate &= ~SPSR_EL1_AARCH32_RES0_BITS;
1391
1392 if (!system_supports_mixed_endian_el0()) {
1393 if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
1394 regs->pstate |= COMPAT_PSR_E_BIT;
1395 else
1396 regs->pstate &= ~COMPAT_PSR_E_BIT;
1397 }
1398
1399 if (user_mode(regs) && (regs->pstate & PSR_MODE32_BIT) &&
1400 (regs->pstate & COMPAT_PSR_A_BIT) == 0 &&
1401 (regs->pstate & COMPAT_PSR_I_BIT) == 0 &&
1402 (regs->pstate & COMPAT_PSR_F_BIT) == 0) {
1403 return 1;
1404 }
1405
1406 /*
1407 * Force PSR to a valid 32-bit EL0t, preserving the same bits as
1408 * arch/arm.
1409 */
1410 regs->pstate &= COMPAT_PSR_N_BIT | COMPAT_PSR_Z_BIT |
1411 COMPAT_PSR_C_BIT | COMPAT_PSR_V_BIT |
1412 COMPAT_PSR_Q_BIT | COMPAT_PSR_IT_MASK |
1413 COMPAT_PSR_GE_MASK | COMPAT_PSR_E_BIT |
1414 COMPAT_PSR_T_BIT;
1415 regs->pstate |= PSR_MODE32_BIT;
1416
1417 return 0;
1418 }
1419
1420 static int valid_native_regs(struct user_pt_regs *regs)
1421 {
1422 regs->pstate &= ~SPSR_EL1_AARCH64_RES0_BITS;
1423
1424 if (user_mode(regs) && !(regs->pstate & PSR_MODE32_BIT) &&
1425 (regs->pstate & PSR_D_BIT) == 0 &&
1426 (regs->pstate & PSR_A_BIT) == 0 &&
1427 (regs->pstate & PSR_I_BIT) == 0 &&
1428 (regs->pstate & PSR_F_BIT) == 0) {
1429 return 1;
1430 }
1431
1432 /* Force PSR to a valid 64-bit EL0t */
1433 regs->pstate &= PSR_N_BIT | PSR_Z_BIT | PSR_C_BIT | PSR_V_BIT;
1434
1435 return 0;
1436 }
1437
1438 /*
1439 * Are the current registers suitable for user mode? (used to maintain
1440 * security in signal handlers)
1441 */
1442 int valid_user_regs(struct user_pt_regs *regs, struct task_struct *task)
1443 {
1444 if (!test_tsk_thread_flag(task, TIF_SINGLESTEP))
1445 regs->pstate &= ~DBG_SPSR_SS;
1446
1447 if (is_compat_thread(task_thread_info(task)))
1448 return valid_compat_regs(regs);
1449 else
1450 return valid_native_regs(regs);
1451 }
Linux kernel - Deliverables
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