xref: /linux/arch/arm64/kernel/ptrace.c (revision ba199dc909a20fe62270ae4e93f263987bb9d119)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Based on arch/arm/kernel/ptrace.c
4  *
5  * By Ross Biro 1/23/92
6  * edited by Linus Torvalds
7  * ARM modifications Copyright (C) 2000 Russell King
8  * Copyright (C) 2012 ARM Ltd.
9  */
10 
11 #include <linux/audit.h>
12 #include <linux/compat.h>
13 #include <linux/kernel.h>
14 #include <linux/sched/signal.h>
15 #include <linux/sched/task_stack.h>
16 #include <linux/mm.h>
17 #include <linux/nospec.h>
18 #include <linux/smp.h>
19 #include <linux/ptrace.h>
20 #include <linux/user.h>
21 #include <linux/seccomp.h>
22 #include <linux/security.h>
23 #include <linux/init.h>
24 #include <linux/signal.h>
25 #include <linux/string.h>
26 #include <linux/uaccess.h>
27 #include <linux/perf_event.h>
28 #include <linux/hw_breakpoint.h>
29 #include <linux/regset.h>
30 #include <linux/elf.h>
31 #include <linux/rseq.h>
32 
33 #include <asm/compat.h>
34 #include <asm/cpufeature.h>
35 #include <asm/debug-monitors.h>
36 #include <asm/fpsimd.h>
37 #include <asm/mte.h>
38 #include <asm/pointer_auth.h>
39 #include <asm/stacktrace.h>
40 #include <asm/syscall.h>
41 #include <asm/traps.h>
42 #include <asm/system_misc.h>
43 
44 #define CREATE_TRACE_POINTS
45 #include <trace/events/syscalls.h>
46 
47 struct pt_regs_offset {
48 	const char *name;
49 	int offset;
50 };
51 
52 #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
53 #define REG_OFFSET_END {.name = NULL, .offset = 0}
54 #define GPR_OFFSET_NAME(r) \
55 	{.name = "x" #r, .offset = offsetof(struct pt_regs, regs[r])}
56 
57 static const struct pt_regs_offset regoffset_table[] = {
58 	GPR_OFFSET_NAME(0),
59 	GPR_OFFSET_NAME(1),
60 	GPR_OFFSET_NAME(2),
61 	GPR_OFFSET_NAME(3),
62 	GPR_OFFSET_NAME(4),
63 	GPR_OFFSET_NAME(5),
64 	GPR_OFFSET_NAME(6),
65 	GPR_OFFSET_NAME(7),
66 	GPR_OFFSET_NAME(8),
67 	GPR_OFFSET_NAME(9),
68 	GPR_OFFSET_NAME(10),
69 	GPR_OFFSET_NAME(11),
70 	GPR_OFFSET_NAME(12),
71 	GPR_OFFSET_NAME(13),
72 	GPR_OFFSET_NAME(14),
73 	GPR_OFFSET_NAME(15),
74 	GPR_OFFSET_NAME(16),
75 	GPR_OFFSET_NAME(17),
76 	GPR_OFFSET_NAME(18),
77 	GPR_OFFSET_NAME(19),
78 	GPR_OFFSET_NAME(20),
79 	GPR_OFFSET_NAME(21),
80 	GPR_OFFSET_NAME(22),
81 	GPR_OFFSET_NAME(23),
82 	GPR_OFFSET_NAME(24),
83 	GPR_OFFSET_NAME(25),
84 	GPR_OFFSET_NAME(26),
85 	GPR_OFFSET_NAME(27),
86 	GPR_OFFSET_NAME(28),
87 	GPR_OFFSET_NAME(29),
88 	GPR_OFFSET_NAME(30),
89 	{.name = "lr", .offset = offsetof(struct pt_regs, regs[30])},
90 	REG_OFFSET_NAME(sp),
91 	REG_OFFSET_NAME(pc),
92 	REG_OFFSET_NAME(pstate),
93 	REG_OFFSET_END,
94 };
95 
96 /**
97  * regs_query_register_offset() - query register offset from its name
98  * @name:	the name of a register
99  *
100  * regs_query_register_offset() returns the offset of a register in struct
101  * pt_regs from its name. If the name is invalid, this returns -EINVAL;
102  */
103 int regs_query_register_offset(const char *name)
104 {
105 	const struct pt_regs_offset *roff;
106 
107 	for (roff = regoffset_table; roff->name != NULL; roff++)
108 		if (!strcmp(roff->name, name))
109 			return roff->offset;
110 	return -EINVAL;
111 }
112 
113 /**
114  * regs_within_kernel_stack() - check the address in the stack
115  * @regs:      pt_regs which contains kernel stack pointer.
116  * @addr:      address which is checked.
117  *
118  * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
119  * If @addr is within the kernel stack, it returns true. If not, returns false.
120  */
121 static bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
122 {
123 	return ((addr & ~(THREAD_SIZE - 1))  ==
124 		(kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1))) ||
125 		on_irq_stack(addr, sizeof(unsigned long));
126 }
127 
128 /**
129  * regs_get_kernel_stack_nth() - get Nth entry of the stack
130  * @regs:	pt_regs which contains kernel stack pointer.
131  * @n:		stack entry number.
132  *
133  * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
134  * is specified by @regs. If the @n th entry is NOT in the kernel stack,
135  * this returns 0.
136  */
137 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
138 {
139 	unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
140 
141 	addr += n;
142 	if (regs_within_kernel_stack(regs, (unsigned long)addr))
143 		return *addr;
144 	else
145 		return 0;
146 }
147 
148 /*
149  * TODO: does not yet catch signals sent when the child dies.
150  * in exit.c or in signal.c.
151  */
152 
153 /*
154  * Called by kernel/ptrace.c when detaching..
155  */
156 void ptrace_disable(struct task_struct *child)
157 {
158 	/*
159 	 * This would be better off in core code, but PTRACE_DETACH has
160 	 * grown its fair share of arch-specific worts and changing it
161 	 * is likely to cause regressions on obscure architectures.
162 	 */
163 	user_disable_single_step(child);
164 }
165 
166 #ifdef CONFIG_HAVE_HW_BREAKPOINT
167 /*
168  * Handle hitting a HW-breakpoint.
169  */
170 static void ptrace_hbptriggered(struct perf_event *bp,
171 				struct perf_sample_data *data,
172 				struct pt_regs *regs)
173 {
174 	struct arch_hw_breakpoint *bkpt = counter_arch_bp(bp);
175 	const char *desc = "Hardware breakpoint trap (ptrace)";
176 
177 	if (is_compat_task()) {
178 		int si_errno = 0;
179 		int i;
180 
181 		for (i = 0; i < ARM_MAX_BRP; ++i) {
182 			if (current->thread.debug.hbp_break[i] == bp) {
183 				si_errno = (i << 1) + 1;
184 				break;
185 			}
186 		}
187 
188 		for (i = 0; i < ARM_MAX_WRP; ++i) {
189 			if (current->thread.debug.hbp_watch[i] == bp) {
190 				si_errno = -((i << 1) + 1);
191 				break;
192 			}
193 		}
194 		arm64_force_sig_ptrace_errno_trap(si_errno, bkpt->trigger,
195 						  desc);
196 		return;
197 	}
198 
199 	arm64_force_sig_fault(SIGTRAP, TRAP_HWBKPT, bkpt->trigger, desc);
200 }
201 
202 /*
203  * Unregister breakpoints from this task and reset the pointers in
204  * the thread_struct.
205  */
206 void flush_ptrace_hw_breakpoint(struct task_struct *tsk)
207 {
208 	int i;
209 	struct thread_struct *t = &tsk->thread;
210 
211 	for (i = 0; i < ARM_MAX_BRP; i++) {
212 		if (t->debug.hbp_break[i]) {
213 			unregister_hw_breakpoint(t->debug.hbp_break[i]);
214 			t->debug.hbp_break[i] = NULL;
215 		}
216 	}
217 
218 	for (i = 0; i < ARM_MAX_WRP; i++) {
219 		if (t->debug.hbp_watch[i]) {
220 			unregister_hw_breakpoint(t->debug.hbp_watch[i]);
221 			t->debug.hbp_watch[i] = NULL;
222 		}
223 	}
224 }
225 
226 void ptrace_hw_copy_thread(struct task_struct *tsk)
227 {
228 	memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
229 }
230 
231 static struct perf_event *ptrace_hbp_get_event(unsigned int note_type,
232 					       struct task_struct *tsk,
233 					       unsigned long idx)
234 {
235 	struct perf_event *bp = ERR_PTR(-EINVAL);
236 
237 	switch (note_type) {
238 	case NT_ARM_HW_BREAK:
239 		if (idx >= ARM_MAX_BRP)
240 			goto out;
241 		idx = array_index_nospec(idx, ARM_MAX_BRP);
242 		bp = tsk->thread.debug.hbp_break[idx];
243 		break;
244 	case NT_ARM_HW_WATCH:
245 		if (idx >= ARM_MAX_WRP)
246 			goto out;
247 		idx = array_index_nospec(idx, ARM_MAX_WRP);
248 		bp = tsk->thread.debug.hbp_watch[idx];
249 		break;
250 	}
251 
252 out:
253 	return bp;
254 }
255 
256 static int ptrace_hbp_set_event(unsigned int note_type,
257 				struct task_struct *tsk,
258 				unsigned long idx,
259 				struct perf_event *bp)
260 {
261 	int err = -EINVAL;
262 
263 	switch (note_type) {
264 	case NT_ARM_HW_BREAK:
265 		if (idx >= ARM_MAX_BRP)
266 			goto out;
267 		idx = array_index_nospec(idx, ARM_MAX_BRP);
268 		tsk->thread.debug.hbp_break[idx] = bp;
269 		err = 0;
270 		break;
271 	case NT_ARM_HW_WATCH:
272 		if (idx >= ARM_MAX_WRP)
273 			goto out;
274 		idx = array_index_nospec(idx, ARM_MAX_WRP);
275 		tsk->thread.debug.hbp_watch[idx] = bp;
276 		err = 0;
277 		break;
278 	}
279 
280 out:
281 	return err;
282 }
283 
284 static struct perf_event *ptrace_hbp_create(unsigned int note_type,
285 					    struct task_struct *tsk,
286 					    unsigned long idx)
287 {
288 	struct perf_event *bp;
289 	struct perf_event_attr attr;
290 	int err, type;
291 
292 	switch (note_type) {
293 	case NT_ARM_HW_BREAK:
294 		type = HW_BREAKPOINT_X;
295 		break;
296 	case NT_ARM_HW_WATCH:
297 		type = HW_BREAKPOINT_RW;
298 		break;
299 	default:
300 		return ERR_PTR(-EINVAL);
301 	}
302 
303 	ptrace_breakpoint_init(&attr);
304 
305 	/*
306 	 * Initialise fields to sane defaults
307 	 * (i.e. values that will pass validation).
308 	 */
309 	attr.bp_addr	= 0;
310 	attr.bp_len	= HW_BREAKPOINT_LEN_4;
311 	attr.bp_type	= type;
312 	attr.disabled	= 1;
313 
314 	bp = register_user_hw_breakpoint(&attr, ptrace_hbptriggered, NULL, tsk);
315 	if (IS_ERR(bp))
316 		return bp;
317 
318 	err = ptrace_hbp_set_event(note_type, tsk, idx, bp);
319 	if (err)
320 		return ERR_PTR(err);
321 
322 	return bp;
323 }
324 
325 static int ptrace_hbp_fill_attr_ctrl(unsigned int note_type,
326 				     struct arch_hw_breakpoint_ctrl ctrl,
327 				     struct perf_event_attr *attr)
328 {
329 	int err, len, type, offset, disabled = !ctrl.enabled;
330 
331 	attr->disabled = disabled;
332 	if (disabled)
333 		return 0;
334 
335 	err = arch_bp_generic_fields(ctrl, &len, &type, &offset);
336 	if (err)
337 		return err;
338 
339 	switch (note_type) {
340 	case NT_ARM_HW_BREAK:
341 		if ((type & HW_BREAKPOINT_X) != type)
342 			return -EINVAL;
343 		break;
344 	case NT_ARM_HW_WATCH:
345 		if ((type & HW_BREAKPOINT_RW) != type)
346 			return -EINVAL;
347 		break;
348 	default:
349 		return -EINVAL;
350 	}
351 
352 	attr->bp_len	= len;
353 	attr->bp_type	= type;
354 	attr->bp_addr	+= offset;
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 ? counter_arch_bp(bp)->address : 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 			struct membuf to)
476 {
477 	unsigned int note_type = regset->core_note_type;
478 	int ret, idx = 0;
479 	u32 info, ctrl;
480 	u64 addr;
481 
482 	/* Resource info */
483 	ret = ptrace_hbp_get_resource_info(note_type, &info);
484 	if (ret)
485 		return ret;
486 
487 	membuf_write(&to, &info, sizeof(info));
488 	membuf_zero(&to, sizeof(u32));
489 	/* (address, ctrl) registers */
490 	while (to.left) {
491 		ret = ptrace_hbp_get_addr(note_type, target, idx, &addr);
492 		if (ret)
493 			return ret;
494 		ret = ptrace_hbp_get_ctrl(note_type, target, idx, &ctrl);
495 		if (ret)
496 			return ret;
497 		membuf_store(&to, addr);
498 		membuf_store(&to, ctrl);
499 		membuf_zero(&to, sizeof(u32));
500 		idx++;
501 	}
502 	return 0;
503 }
504 
505 static int hw_break_set(struct task_struct *target,
506 			const struct user_regset *regset,
507 			unsigned int pos, unsigned int count,
508 			const void *kbuf, const void __user *ubuf)
509 {
510 	unsigned int note_type = regset->core_note_type;
511 	int ret, idx = 0, offset, limit;
512 	u32 ctrl;
513 	u64 addr;
514 
515 	/* Resource info and pad */
516 	offset = offsetof(struct user_hwdebug_state, dbg_regs);
517 	user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, offset);
518 
519 	/* (address, ctrl) registers */
520 	limit = regset->n * regset->size;
521 	while (count && offset < limit) {
522 		if (count < PTRACE_HBP_ADDR_SZ)
523 			return -EINVAL;
524 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &addr,
525 					 offset, offset + PTRACE_HBP_ADDR_SZ);
526 		if (ret)
527 			return ret;
528 		ret = ptrace_hbp_set_addr(note_type, target, idx, addr);
529 		if (ret)
530 			return ret;
531 		offset += PTRACE_HBP_ADDR_SZ;
532 
533 		if (!count)
534 			break;
535 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl,
536 					 offset, offset + PTRACE_HBP_CTRL_SZ);
537 		if (ret)
538 			return ret;
539 		ret = ptrace_hbp_set_ctrl(note_type, target, idx, ctrl);
540 		if (ret)
541 			return ret;
542 		offset += PTRACE_HBP_CTRL_SZ;
543 
544 		user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
545 					  offset, offset + PTRACE_HBP_PAD_SZ);
546 		offset += PTRACE_HBP_PAD_SZ;
547 		idx++;
548 	}
549 
550 	return 0;
551 }
552 #endif	/* CONFIG_HAVE_HW_BREAKPOINT */
553 
554 static int gpr_get(struct task_struct *target,
555 		   const struct user_regset *regset,
556 		   struct membuf to)
557 {
558 	struct user_pt_regs *uregs = &task_pt_regs(target)->user_regs;
559 	return membuf_write(&to, uregs, sizeof(*uregs));
560 }
561 
562 static int gpr_set(struct task_struct *target, const struct user_regset *regset,
563 		   unsigned int pos, unsigned int count,
564 		   const void *kbuf, const void __user *ubuf)
565 {
566 	int ret;
567 	struct user_pt_regs newregs = task_pt_regs(target)->user_regs;
568 
569 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newregs, 0, -1);
570 	if (ret)
571 		return ret;
572 
573 	if (!valid_user_regs(&newregs, target))
574 		return -EINVAL;
575 
576 	task_pt_regs(target)->user_regs = newregs;
577 	return 0;
578 }
579 
580 static int fpr_active(struct task_struct *target, const struct user_regset *regset)
581 {
582 	if (!system_supports_fpsimd())
583 		return -ENODEV;
584 	return regset->n;
585 }
586 
587 /*
588  * TODO: update fp accessors for lazy context switching (sync/flush hwstate)
589  */
590 static int __fpr_get(struct task_struct *target,
591 		     const struct user_regset *regset,
592 		     struct membuf to)
593 {
594 	struct user_fpsimd_state *uregs;
595 
596 	sve_sync_to_fpsimd(target);
597 
598 	uregs = &target->thread.uw.fpsimd_state;
599 
600 	return membuf_write(&to, uregs, sizeof(*uregs));
601 }
602 
603 static int fpr_get(struct task_struct *target, const struct user_regset *regset,
604 		   struct membuf to)
605 {
606 	if (!system_supports_fpsimd())
607 		return -EINVAL;
608 
609 	if (target == current)
610 		fpsimd_preserve_current_state();
611 
612 	return __fpr_get(target, regset, to);
613 }
614 
615 static int __fpr_set(struct task_struct *target,
616 		     const struct user_regset *regset,
617 		     unsigned int pos, unsigned int count,
618 		     const void *kbuf, const void __user *ubuf,
619 		     unsigned int start_pos)
620 {
621 	int ret;
622 	struct user_fpsimd_state newstate;
623 
624 	/*
625 	 * Ensure target->thread.uw.fpsimd_state is up to date, so that a
626 	 * short copyin can't resurrect stale data.
627 	 */
628 	sve_sync_to_fpsimd(target);
629 
630 	newstate = target->thread.uw.fpsimd_state;
631 
632 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newstate,
633 				 start_pos, start_pos + sizeof(newstate));
634 	if (ret)
635 		return ret;
636 
637 	target->thread.uw.fpsimd_state = newstate;
638 
639 	return ret;
640 }
641 
642 static int fpr_set(struct task_struct *target, const struct user_regset *regset,
643 		   unsigned int pos, unsigned int count,
644 		   const void *kbuf, const void __user *ubuf)
645 {
646 	int ret;
647 
648 	if (!system_supports_fpsimd())
649 		return -EINVAL;
650 
651 	ret = __fpr_set(target, regset, pos, count, kbuf, ubuf, 0);
652 	if (ret)
653 		return ret;
654 
655 	sve_sync_from_fpsimd_zeropad(target);
656 	fpsimd_flush_task_state(target);
657 
658 	return ret;
659 }
660 
661 static int tls_get(struct task_struct *target, const struct user_regset *regset,
662 		   struct membuf to)
663 {
664 	int ret;
665 
666 	if (target == current)
667 		tls_preserve_current_state();
668 
669 	ret = membuf_store(&to, target->thread.uw.tp_value);
670 	if (system_supports_tpidr2())
671 		ret = membuf_store(&to, target->thread.tpidr2_el0);
672 	else
673 		ret = membuf_zero(&to, sizeof(u64));
674 
675 	return ret;
676 }
677 
678 static int tls_set(struct task_struct *target, const struct user_regset *regset,
679 		   unsigned int pos, unsigned int count,
680 		   const void *kbuf, const void __user *ubuf)
681 {
682 	int ret;
683 	unsigned long tls[2];
684 
685 	tls[0] = target->thread.uw.tp_value;
686 	if (system_supports_tpidr2())
687 		tls[1] = target->thread.tpidr2_el0;
688 
689 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, tls, 0, count);
690 	if (ret)
691 		return ret;
692 
693 	target->thread.uw.tp_value = tls[0];
694 	if (system_supports_tpidr2())
695 		target->thread.tpidr2_el0 = tls[1];
696 
697 	return ret;
698 }
699 
700 static int fpmr_get(struct task_struct *target, const struct user_regset *regset,
701 		   struct membuf to)
702 {
703 	if (!system_supports_fpmr())
704 		return -EINVAL;
705 
706 	if (target == current)
707 		fpsimd_preserve_current_state();
708 
709 	return membuf_store(&to, target->thread.uw.fpmr);
710 }
711 
712 static int fpmr_set(struct task_struct *target, const struct user_regset *regset,
713 		   unsigned int pos, unsigned int count,
714 		   const void *kbuf, const void __user *ubuf)
715 {
716 	int ret;
717 	unsigned long fpmr;
718 
719 	if (!system_supports_fpmr())
720 		return -EINVAL;
721 
722 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fpmr, 0, count);
723 	if (ret)
724 		return ret;
725 
726 	target->thread.uw.fpmr = fpmr;
727 
728 	fpsimd_flush_task_state(target);
729 
730 	return 0;
731 }
732 
733 static int system_call_get(struct task_struct *target,
734 			   const struct user_regset *regset,
735 			   struct membuf to)
736 {
737 	return membuf_store(&to, task_pt_regs(target)->syscallno);
738 }
739 
740 static int system_call_set(struct task_struct *target,
741 			   const struct user_regset *regset,
742 			   unsigned int pos, unsigned int count,
743 			   const void *kbuf, const void __user *ubuf)
744 {
745 	int syscallno = task_pt_regs(target)->syscallno;
746 	int ret;
747 
748 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &syscallno, 0, -1);
749 	if (ret)
750 		return ret;
751 
752 	task_pt_regs(target)->syscallno = syscallno;
753 	return ret;
754 }
755 
756 #ifdef CONFIG_ARM64_SVE
757 
758 static void sve_init_header_from_task(struct user_sve_header *header,
759 				      struct task_struct *target,
760 				      enum vec_type type)
761 {
762 	unsigned int vq;
763 	bool active;
764 	enum vec_type task_type;
765 
766 	memset(header, 0, sizeof(*header));
767 
768 	/* Check if the requested registers are active for the task */
769 	if (thread_sm_enabled(&target->thread))
770 		task_type = ARM64_VEC_SME;
771 	else
772 		task_type = ARM64_VEC_SVE;
773 	active = (task_type == type);
774 
775 	switch (type) {
776 	case ARM64_VEC_SVE:
777 		if (test_tsk_thread_flag(target, TIF_SVE_VL_INHERIT))
778 			header->flags |= SVE_PT_VL_INHERIT;
779 		break;
780 	case ARM64_VEC_SME:
781 		if (test_tsk_thread_flag(target, TIF_SME_VL_INHERIT))
782 			header->flags |= SVE_PT_VL_INHERIT;
783 		break;
784 	default:
785 		WARN_ON_ONCE(1);
786 		return;
787 	}
788 
789 	if (active) {
790 		if (target->thread.fp_type == FP_STATE_FPSIMD) {
791 			header->flags |= SVE_PT_REGS_FPSIMD;
792 		} else {
793 			header->flags |= SVE_PT_REGS_SVE;
794 		}
795 	}
796 
797 	header->vl = task_get_vl(target, type);
798 	vq = sve_vq_from_vl(header->vl);
799 
800 	header->max_vl = vec_max_vl(type);
801 	header->size = SVE_PT_SIZE(vq, header->flags);
802 	header->max_size = SVE_PT_SIZE(sve_vq_from_vl(header->max_vl),
803 				      SVE_PT_REGS_SVE);
804 }
805 
806 static unsigned int sve_size_from_header(struct user_sve_header const *header)
807 {
808 	return ALIGN(header->size, SVE_VQ_BYTES);
809 }
810 
811 static int sve_get_common(struct task_struct *target,
812 			  const struct user_regset *regset,
813 			  struct membuf to,
814 			  enum vec_type type)
815 {
816 	struct user_sve_header header;
817 	unsigned int vq;
818 	unsigned long start, end;
819 
820 	/* Header */
821 	sve_init_header_from_task(&header, target, type);
822 	vq = sve_vq_from_vl(header.vl);
823 
824 	membuf_write(&to, &header, sizeof(header));
825 
826 	if (target == current)
827 		fpsimd_preserve_current_state();
828 
829 	BUILD_BUG_ON(SVE_PT_FPSIMD_OFFSET != sizeof(header));
830 	BUILD_BUG_ON(SVE_PT_SVE_OFFSET != sizeof(header));
831 
832 	switch ((header.flags & SVE_PT_REGS_MASK)) {
833 	case SVE_PT_REGS_FPSIMD:
834 		return __fpr_get(target, regset, to);
835 
836 	case SVE_PT_REGS_SVE:
837 		start = SVE_PT_SVE_OFFSET;
838 		end = SVE_PT_SVE_FFR_OFFSET(vq) + SVE_PT_SVE_FFR_SIZE(vq);
839 		membuf_write(&to, target->thread.sve_state, end - start);
840 
841 		start = end;
842 		end = SVE_PT_SVE_FPSR_OFFSET(vq);
843 		membuf_zero(&to, end - start);
844 
845 		/*
846 		 * Copy fpsr, and fpcr which must follow contiguously in
847 		 * struct fpsimd_state:
848 		 */
849 		start = end;
850 		end = SVE_PT_SVE_FPCR_OFFSET(vq) + SVE_PT_SVE_FPCR_SIZE;
851 		membuf_write(&to, &target->thread.uw.fpsimd_state.fpsr,
852 			     end - start);
853 
854 		start = end;
855 		end = sve_size_from_header(&header);
856 		return membuf_zero(&to, end - start);
857 
858 	default:
859 		return 0;
860 	}
861 }
862 
863 static int sve_get(struct task_struct *target,
864 		   const struct user_regset *regset,
865 		   struct membuf to)
866 {
867 	if (!system_supports_sve())
868 		return -EINVAL;
869 
870 	return sve_get_common(target, regset, to, ARM64_VEC_SVE);
871 }
872 
873 static int sve_set_common(struct task_struct *target,
874 			  const struct user_regset *regset,
875 			  unsigned int pos, unsigned int count,
876 			  const void *kbuf, const void __user *ubuf,
877 			  enum vec_type type)
878 {
879 	int ret;
880 	struct user_sve_header header;
881 	unsigned int vq;
882 	unsigned long start, end;
883 
884 	/* Header */
885 	if (count < sizeof(header))
886 		return -EINVAL;
887 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &header,
888 				 0, sizeof(header));
889 	if (ret)
890 		goto out;
891 
892 	/*
893 	 * Apart from SVE_PT_REGS_MASK, all SVE_PT_* flags are consumed by
894 	 * vec_set_vector_length(), which will also validate them for us:
895 	 */
896 	ret = vec_set_vector_length(target, type, header.vl,
897 		((unsigned long)header.flags & ~SVE_PT_REGS_MASK) << 16);
898 	if (ret)
899 		goto out;
900 
901 	/* Actual VL set may be less than the user asked for: */
902 	vq = sve_vq_from_vl(task_get_vl(target, type));
903 
904 	/* Enter/exit streaming mode */
905 	if (system_supports_sme()) {
906 		u64 old_svcr = target->thread.svcr;
907 
908 		switch (type) {
909 		case ARM64_VEC_SVE:
910 			target->thread.svcr &= ~SVCR_SM_MASK;
911 			break;
912 		case ARM64_VEC_SME:
913 			target->thread.svcr |= SVCR_SM_MASK;
914 
915 			/*
916 			 * Disable traps and ensure there is SME storage but
917 			 * preserve any currently set values in ZA/ZT.
918 			 */
919 			sme_alloc(target, false);
920 			set_tsk_thread_flag(target, TIF_SME);
921 			break;
922 		default:
923 			WARN_ON_ONCE(1);
924 			ret = -EINVAL;
925 			goto out;
926 		}
927 
928 		/*
929 		 * If we switched then invalidate any existing SVE
930 		 * state and ensure there's storage.
931 		 */
932 		if (target->thread.svcr != old_svcr)
933 			sve_alloc(target, true);
934 	}
935 
936 	/* Registers: FPSIMD-only case */
937 
938 	BUILD_BUG_ON(SVE_PT_FPSIMD_OFFSET != sizeof(header));
939 	if ((header.flags & SVE_PT_REGS_MASK) == SVE_PT_REGS_FPSIMD) {
940 		ret = __fpr_set(target, regset, pos, count, kbuf, ubuf,
941 				SVE_PT_FPSIMD_OFFSET);
942 		clear_tsk_thread_flag(target, TIF_SVE);
943 		target->thread.fp_type = FP_STATE_FPSIMD;
944 		goto out;
945 	}
946 
947 	/*
948 	 * Otherwise: no registers or full SVE case.  For backwards
949 	 * compatibility reasons we treat empty flags as SVE registers.
950 	 */
951 
952 	/*
953 	 * If setting a different VL from the requested VL and there is
954 	 * register data, the data layout will be wrong: don't even
955 	 * try to set the registers in this case.
956 	 */
957 	if (count && vq != sve_vq_from_vl(header.vl)) {
958 		ret = -EIO;
959 		goto out;
960 	}
961 
962 	sve_alloc(target, true);
963 	if (!target->thread.sve_state) {
964 		ret = -ENOMEM;
965 		clear_tsk_thread_flag(target, TIF_SVE);
966 		target->thread.fp_type = FP_STATE_FPSIMD;
967 		goto out;
968 	}
969 
970 	/*
971 	 * Ensure target->thread.sve_state is up to date with target's
972 	 * FPSIMD regs, so that a short copyin leaves trailing
973 	 * registers unmodified.  Only enable SVE if we are
974 	 * configuring normal SVE, a system with streaming SVE may not
975 	 * have normal SVE.
976 	 */
977 	fpsimd_sync_to_sve(target);
978 	if (type == ARM64_VEC_SVE)
979 		set_tsk_thread_flag(target, TIF_SVE);
980 	target->thread.fp_type = FP_STATE_SVE;
981 
982 	BUILD_BUG_ON(SVE_PT_SVE_OFFSET != sizeof(header));
983 	start = SVE_PT_SVE_OFFSET;
984 	end = SVE_PT_SVE_FFR_OFFSET(vq) + SVE_PT_SVE_FFR_SIZE(vq);
985 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
986 				 target->thread.sve_state,
987 				 start, end);
988 	if (ret)
989 		goto out;
990 
991 	start = end;
992 	end = SVE_PT_SVE_FPSR_OFFSET(vq);
993 	user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, start, end);
994 
995 	/*
996 	 * Copy fpsr, and fpcr which must follow contiguously in
997 	 * struct fpsimd_state:
998 	 */
999 	start = end;
1000 	end = SVE_PT_SVE_FPCR_OFFSET(vq) + SVE_PT_SVE_FPCR_SIZE;
1001 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1002 				 &target->thread.uw.fpsimd_state.fpsr,
1003 				 start, end);
1004 
1005 out:
1006 	fpsimd_flush_task_state(target);
1007 	return ret;
1008 }
1009 
1010 static int sve_set(struct task_struct *target,
1011 		   const struct user_regset *regset,
1012 		   unsigned int pos, unsigned int count,
1013 		   const void *kbuf, const void __user *ubuf)
1014 {
1015 	if (!system_supports_sve())
1016 		return -EINVAL;
1017 
1018 	return sve_set_common(target, regset, pos, count, kbuf, ubuf,
1019 			      ARM64_VEC_SVE);
1020 }
1021 
1022 #endif /* CONFIG_ARM64_SVE */
1023 
1024 #ifdef CONFIG_ARM64_SME
1025 
1026 static int ssve_get(struct task_struct *target,
1027 		   const struct user_regset *regset,
1028 		   struct membuf to)
1029 {
1030 	if (!system_supports_sme())
1031 		return -EINVAL;
1032 
1033 	return sve_get_common(target, regset, to, ARM64_VEC_SME);
1034 }
1035 
1036 static int ssve_set(struct task_struct *target,
1037 		    const struct user_regset *regset,
1038 		    unsigned int pos, unsigned int count,
1039 		    const void *kbuf, const void __user *ubuf)
1040 {
1041 	if (!system_supports_sme())
1042 		return -EINVAL;
1043 
1044 	return sve_set_common(target, regset, pos, count, kbuf, ubuf,
1045 			      ARM64_VEC_SME);
1046 }
1047 
1048 static int za_get(struct task_struct *target,
1049 		  const struct user_regset *regset,
1050 		  struct membuf to)
1051 {
1052 	struct user_za_header header;
1053 	unsigned int vq;
1054 	unsigned long start, end;
1055 
1056 	if (!system_supports_sme())
1057 		return -EINVAL;
1058 
1059 	/* Header */
1060 	memset(&header, 0, sizeof(header));
1061 
1062 	if (test_tsk_thread_flag(target, TIF_SME_VL_INHERIT))
1063 		header.flags |= ZA_PT_VL_INHERIT;
1064 
1065 	header.vl = task_get_sme_vl(target);
1066 	vq = sve_vq_from_vl(header.vl);
1067 	header.max_vl = sme_max_vl();
1068 	header.max_size = ZA_PT_SIZE(vq);
1069 
1070 	/* If ZA is not active there is only the header */
1071 	if (thread_za_enabled(&target->thread))
1072 		header.size = ZA_PT_SIZE(vq);
1073 	else
1074 		header.size = ZA_PT_ZA_OFFSET;
1075 
1076 	membuf_write(&to, &header, sizeof(header));
1077 
1078 	BUILD_BUG_ON(ZA_PT_ZA_OFFSET != sizeof(header));
1079 	end = ZA_PT_ZA_OFFSET;
1080 
1081 	if (target == current)
1082 		fpsimd_preserve_current_state();
1083 
1084 	/* Any register data to include? */
1085 	if (thread_za_enabled(&target->thread)) {
1086 		start = end;
1087 		end = ZA_PT_SIZE(vq);
1088 		membuf_write(&to, target->thread.sme_state, end - start);
1089 	}
1090 
1091 	/* Zero any trailing padding */
1092 	start = end;
1093 	end = ALIGN(header.size, SVE_VQ_BYTES);
1094 	return membuf_zero(&to, end - start);
1095 }
1096 
1097 static int za_set(struct task_struct *target,
1098 		  const struct user_regset *regset,
1099 		  unsigned int pos, unsigned int count,
1100 		  const void *kbuf, const void __user *ubuf)
1101 {
1102 	int ret;
1103 	struct user_za_header header;
1104 	unsigned int vq;
1105 	unsigned long start, end;
1106 
1107 	if (!system_supports_sme())
1108 		return -EINVAL;
1109 
1110 	/* Header */
1111 	if (count < sizeof(header))
1112 		return -EINVAL;
1113 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &header,
1114 				 0, sizeof(header));
1115 	if (ret)
1116 		goto out;
1117 
1118 	/*
1119 	 * All current ZA_PT_* flags are consumed by
1120 	 * vec_set_vector_length(), which will also validate them for
1121 	 * us:
1122 	 */
1123 	ret = vec_set_vector_length(target, ARM64_VEC_SME, header.vl,
1124 		((unsigned long)header.flags) << 16);
1125 	if (ret)
1126 		goto out;
1127 
1128 	/* Actual VL set may be less than the user asked for: */
1129 	vq = sve_vq_from_vl(task_get_sme_vl(target));
1130 
1131 	/* Ensure there is some SVE storage for streaming mode */
1132 	if (!target->thread.sve_state) {
1133 		sve_alloc(target, false);
1134 		if (!target->thread.sve_state) {
1135 			ret = -ENOMEM;
1136 			goto out;
1137 		}
1138 	}
1139 
1140 	/*
1141 	 * Only flush the storage if PSTATE.ZA was not already set,
1142 	 * otherwise preserve any existing data.
1143 	 */
1144 	sme_alloc(target, !thread_za_enabled(&target->thread));
1145 	if (!target->thread.sme_state)
1146 		return -ENOMEM;
1147 
1148 	/* If there is no data then disable ZA */
1149 	if (!count) {
1150 		target->thread.svcr &= ~SVCR_ZA_MASK;
1151 		goto out;
1152 	}
1153 
1154 	/*
1155 	 * If setting a different VL from the requested VL and there is
1156 	 * register data, the data layout will be wrong: don't even
1157 	 * try to set the registers in this case.
1158 	 */
1159 	if (vq != sve_vq_from_vl(header.vl)) {
1160 		ret = -EIO;
1161 		goto out;
1162 	}
1163 
1164 	BUILD_BUG_ON(ZA_PT_ZA_OFFSET != sizeof(header));
1165 	start = ZA_PT_ZA_OFFSET;
1166 	end = ZA_PT_SIZE(vq);
1167 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1168 				 target->thread.sme_state,
1169 				 start, end);
1170 	if (ret)
1171 		goto out;
1172 
1173 	/* Mark ZA as active and let userspace use it */
1174 	set_tsk_thread_flag(target, TIF_SME);
1175 	target->thread.svcr |= SVCR_ZA_MASK;
1176 
1177 out:
1178 	fpsimd_flush_task_state(target);
1179 	return ret;
1180 }
1181 
1182 static int zt_get(struct task_struct *target,
1183 		  const struct user_regset *regset,
1184 		  struct membuf to)
1185 {
1186 	if (!system_supports_sme2())
1187 		return -EINVAL;
1188 
1189 	/*
1190 	 * If PSTATE.ZA is not set then ZT will be zeroed when it is
1191 	 * enabled so report the current register value as zero.
1192 	 */
1193 	if (thread_za_enabled(&target->thread))
1194 		membuf_write(&to, thread_zt_state(&target->thread),
1195 			     ZT_SIG_REG_BYTES);
1196 	else
1197 		membuf_zero(&to, ZT_SIG_REG_BYTES);
1198 
1199 	return 0;
1200 }
1201 
1202 static int zt_set(struct task_struct *target,
1203 		  const struct user_regset *regset,
1204 		  unsigned int pos, unsigned int count,
1205 		  const void *kbuf, const void __user *ubuf)
1206 {
1207 	int ret;
1208 
1209 	if (!system_supports_sme2())
1210 		return -EINVAL;
1211 
1212 	/* Ensure SVE storage in case this is first use of SME */
1213 	sve_alloc(target, false);
1214 	if (!target->thread.sve_state)
1215 		return -ENOMEM;
1216 
1217 	if (!thread_za_enabled(&target->thread)) {
1218 		sme_alloc(target, true);
1219 		if (!target->thread.sme_state)
1220 			return -ENOMEM;
1221 	}
1222 
1223 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1224 				 thread_zt_state(&target->thread),
1225 				 0, ZT_SIG_REG_BYTES);
1226 	if (ret == 0) {
1227 		target->thread.svcr |= SVCR_ZA_MASK;
1228 		set_tsk_thread_flag(target, TIF_SME);
1229 	}
1230 
1231 	fpsimd_flush_task_state(target);
1232 
1233 	return ret;
1234 }
1235 
1236 #endif /* CONFIG_ARM64_SME */
1237 
1238 #ifdef CONFIG_ARM64_PTR_AUTH
1239 static int pac_mask_get(struct task_struct *target,
1240 			const struct user_regset *regset,
1241 			struct membuf to)
1242 {
1243 	/*
1244 	 * The PAC bits can differ across data and instruction pointers
1245 	 * depending on TCR_EL1.TBID*, which we may make use of in future, so
1246 	 * we expose separate masks.
1247 	 */
1248 	unsigned long mask = ptrauth_user_pac_mask();
1249 	struct user_pac_mask uregs = {
1250 		.data_mask = mask,
1251 		.insn_mask = mask,
1252 	};
1253 
1254 	if (!system_supports_address_auth())
1255 		return -EINVAL;
1256 
1257 	return membuf_write(&to, &uregs, sizeof(uregs));
1258 }
1259 
1260 static int pac_enabled_keys_get(struct task_struct *target,
1261 				const struct user_regset *regset,
1262 				struct membuf to)
1263 {
1264 	long enabled_keys = ptrauth_get_enabled_keys(target);
1265 
1266 	if (IS_ERR_VALUE(enabled_keys))
1267 		return enabled_keys;
1268 
1269 	return membuf_write(&to, &enabled_keys, sizeof(enabled_keys));
1270 }
1271 
1272 static int pac_enabled_keys_set(struct task_struct *target,
1273 				const struct user_regset *regset,
1274 				unsigned int pos, unsigned int count,
1275 				const void *kbuf, const void __user *ubuf)
1276 {
1277 	int ret;
1278 	long enabled_keys = ptrauth_get_enabled_keys(target);
1279 
1280 	if (IS_ERR_VALUE(enabled_keys))
1281 		return enabled_keys;
1282 
1283 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &enabled_keys, 0,
1284 				 sizeof(long));
1285 	if (ret)
1286 		return ret;
1287 
1288 	return ptrauth_set_enabled_keys(target, PR_PAC_ENABLED_KEYS_MASK,
1289 					enabled_keys);
1290 }
1291 
1292 #ifdef CONFIG_CHECKPOINT_RESTORE
1293 static __uint128_t pac_key_to_user(const struct ptrauth_key *key)
1294 {
1295 	return (__uint128_t)key->hi << 64 | key->lo;
1296 }
1297 
1298 static struct ptrauth_key pac_key_from_user(__uint128_t ukey)
1299 {
1300 	struct ptrauth_key key = {
1301 		.lo = (unsigned long)ukey,
1302 		.hi = (unsigned long)(ukey >> 64),
1303 	};
1304 
1305 	return key;
1306 }
1307 
1308 static void pac_address_keys_to_user(struct user_pac_address_keys *ukeys,
1309 				     const struct ptrauth_keys_user *keys)
1310 {
1311 	ukeys->apiakey = pac_key_to_user(&keys->apia);
1312 	ukeys->apibkey = pac_key_to_user(&keys->apib);
1313 	ukeys->apdakey = pac_key_to_user(&keys->apda);
1314 	ukeys->apdbkey = pac_key_to_user(&keys->apdb);
1315 }
1316 
1317 static void pac_address_keys_from_user(struct ptrauth_keys_user *keys,
1318 				       const struct user_pac_address_keys *ukeys)
1319 {
1320 	keys->apia = pac_key_from_user(ukeys->apiakey);
1321 	keys->apib = pac_key_from_user(ukeys->apibkey);
1322 	keys->apda = pac_key_from_user(ukeys->apdakey);
1323 	keys->apdb = pac_key_from_user(ukeys->apdbkey);
1324 }
1325 
1326 static int pac_address_keys_get(struct task_struct *target,
1327 				const struct user_regset *regset,
1328 				struct membuf to)
1329 {
1330 	struct ptrauth_keys_user *keys = &target->thread.keys_user;
1331 	struct user_pac_address_keys user_keys;
1332 
1333 	if (!system_supports_address_auth())
1334 		return -EINVAL;
1335 
1336 	pac_address_keys_to_user(&user_keys, keys);
1337 
1338 	return membuf_write(&to, &user_keys, sizeof(user_keys));
1339 }
1340 
1341 static int pac_address_keys_set(struct task_struct *target,
1342 				const struct user_regset *regset,
1343 				unsigned int pos, unsigned int count,
1344 				const void *kbuf, const void __user *ubuf)
1345 {
1346 	struct ptrauth_keys_user *keys = &target->thread.keys_user;
1347 	struct user_pac_address_keys user_keys;
1348 	int ret;
1349 
1350 	if (!system_supports_address_auth())
1351 		return -EINVAL;
1352 
1353 	pac_address_keys_to_user(&user_keys, keys);
1354 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1355 				 &user_keys, 0, -1);
1356 	if (ret)
1357 		return ret;
1358 	pac_address_keys_from_user(keys, &user_keys);
1359 
1360 	return 0;
1361 }
1362 
1363 static void pac_generic_keys_to_user(struct user_pac_generic_keys *ukeys,
1364 				     const struct ptrauth_keys_user *keys)
1365 {
1366 	ukeys->apgakey = pac_key_to_user(&keys->apga);
1367 }
1368 
1369 static void pac_generic_keys_from_user(struct ptrauth_keys_user *keys,
1370 				       const struct user_pac_generic_keys *ukeys)
1371 {
1372 	keys->apga = pac_key_from_user(ukeys->apgakey);
1373 }
1374 
1375 static int pac_generic_keys_get(struct task_struct *target,
1376 				const struct user_regset *regset,
1377 				struct membuf to)
1378 {
1379 	struct ptrauth_keys_user *keys = &target->thread.keys_user;
1380 	struct user_pac_generic_keys user_keys;
1381 
1382 	if (!system_supports_generic_auth())
1383 		return -EINVAL;
1384 
1385 	pac_generic_keys_to_user(&user_keys, keys);
1386 
1387 	return membuf_write(&to, &user_keys, sizeof(user_keys));
1388 }
1389 
1390 static int pac_generic_keys_set(struct task_struct *target,
1391 				const struct user_regset *regset,
1392 				unsigned int pos, unsigned int count,
1393 				const void *kbuf, const void __user *ubuf)
1394 {
1395 	struct ptrauth_keys_user *keys = &target->thread.keys_user;
1396 	struct user_pac_generic_keys user_keys;
1397 	int ret;
1398 
1399 	if (!system_supports_generic_auth())
1400 		return -EINVAL;
1401 
1402 	pac_generic_keys_to_user(&user_keys, keys);
1403 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1404 				 &user_keys, 0, -1);
1405 	if (ret)
1406 		return ret;
1407 	pac_generic_keys_from_user(keys, &user_keys);
1408 
1409 	return 0;
1410 }
1411 #endif /* CONFIG_CHECKPOINT_RESTORE */
1412 #endif /* CONFIG_ARM64_PTR_AUTH */
1413 
1414 #ifdef CONFIG_ARM64_TAGGED_ADDR_ABI
1415 static int tagged_addr_ctrl_get(struct task_struct *target,
1416 				const struct user_regset *regset,
1417 				struct membuf to)
1418 {
1419 	long ctrl = get_tagged_addr_ctrl(target);
1420 
1421 	if (IS_ERR_VALUE(ctrl))
1422 		return ctrl;
1423 
1424 	return membuf_write(&to, &ctrl, sizeof(ctrl));
1425 }
1426 
1427 static int tagged_addr_ctrl_set(struct task_struct *target, const struct
1428 				user_regset *regset, unsigned int pos,
1429 				unsigned int count, const void *kbuf, const
1430 				void __user *ubuf)
1431 {
1432 	int ret;
1433 	long ctrl;
1434 
1435 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl, 0, -1);
1436 	if (ret)
1437 		return ret;
1438 
1439 	return set_tagged_addr_ctrl(target, ctrl);
1440 }
1441 #endif
1442 
1443 enum aarch64_regset {
1444 	REGSET_GPR,
1445 	REGSET_FPR,
1446 	REGSET_TLS,
1447 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1448 	REGSET_HW_BREAK,
1449 	REGSET_HW_WATCH,
1450 #endif
1451 	REGSET_FPMR,
1452 	REGSET_SYSTEM_CALL,
1453 #ifdef CONFIG_ARM64_SVE
1454 	REGSET_SVE,
1455 #endif
1456 #ifdef CONFIG_ARM64_SME
1457 	REGSET_SSVE,
1458 	REGSET_ZA,
1459 	REGSET_ZT,
1460 #endif
1461 #ifdef CONFIG_ARM64_PTR_AUTH
1462 	REGSET_PAC_MASK,
1463 	REGSET_PAC_ENABLED_KEYS,
1464 #ifdef CONFIG_CHECKPOINT_RESTORE
1465 	REGSET_PACA_KEYS,
1466 	REGSET_PACG_KEYS,
1467 #endif
1468 #endif
1469 #ifdef CONFIG_ARM64_TAGGED_ADDR_ABI
1470 	REGSET_TAGGED_ADDR_CTRL,
1471 #endif
1472 };
1473 
1474 static const struct user_regset aarch64_regsets[] = {
1475 	[REGSET_GPR] = {
1476 		.core_note_type = NT_PRSTATUS,
1477 		.n = sizeof(struct user_pt_regs) / sizeof(u64),
1478 		.size = sizeof(u64),
1479 		.align = sizeof(u64),
1480 		.regset_get = gpr_get,
1481 		.set = gpr_set
1482 	},
1483 	[REGSET_FPR] = {
1484 		.core_note_type = NT_PRFPREG,
1485 		.n = sizeof(struct user_fpsimd_state) / sizeof(u32),
1486 		/*
1487 		 * We pretend we have 32-bit registers because the fpsr and
1488 		 * fpcr are 32-bits wide.
1489 		 */
1490 		.size = sizeof(u32),
1491 		.align = sizeof(u32),
1492 		.active = fpr_active,
1493 		.regset_get = fpr_get,
1494 		.set = fpr_set
1495 	},
1496 	[REGSET_TLS] = {
1497 		.core_note_type = NT_ARM_TLS,
1498 		.n = 2,
1499 		.size = sizeof(void *),
1500 		.align = sizeof(void *),
1501 		.regset_get = tls_get,
1502 		.set = tls_set,
1503 	},
1504 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1505 	[REGSET_HW_BREAK] = {
1506 		.core_note_type = NT_ARM_HW_BREAK,
1507 		.n = sizeof(struct user_hwdebug_state) / sizeof(u32),
1508 		.size = sizeof(u32),
1509 		.align = sizeof(u32),
1510 		.regset_get = hw_break_get,
1511 		.set = hw_break_set,
1512 	},
1513 	[REGSET_HW_WATCH] = {
1514 		.core_note_type = NT_ARM_HW_WATCH,
1515 		.n = sizeof(struct user_hwdebug_state) / sizeof(u32),
1516 		.size = sizeof(u32),
1517 		.align = sizeof(u32),
1518 		.regset_get = hw_break_get,
1519 		.set = hw_break_set,
1520 	},
1521 #endif
1522 	[REGSET_SYSTEM_CALL] = {
1523 		.core_note_type = NT_ARM_SYSTEM_CALL,
1524 		.n = 1,
1525 		.size = sizeof(int),
1526 		.align = sizeof(int),
1527 		.regset_get = system_call_get,
1528 		.set = system_call_set,
1529 	},
1530 	[REGSET_FPMR] = {
1531 		.core_note_type = NT_ARM_FPMR,
1532 		.n = 1,
1533 		.size = sizeof(u64),
1534 		.align = sizeof(u64),
1535 		.regset_get = fpmr_get,
1536 		.set = fpmr_set,
1537 	},
1538 #ifdef CONFIG_ARM64_SVE
1539 	[REGSET_SVE] = { /* Scalable Vector Extension */
1540 		.core_note_type = NT_ARM_SVE,
1541 		.n = DIV_ROUND_UP(SVE_PT_SIZE(ARCH_SVE_VQ_MAX,
1542 					      SVE_PT_REGS_SVE),
1543 				  SVE_VQ_BYTES),
1544 		.size = SVE_VQ_BYTES,
1545 		.align = SVE_VQ_BYTES,
1546 		.regset_get = sve_get,
1547 		.set = sve_set,
1548 	},
1549 #endif
1550 #ifdef CONFIG_ARM64_SME
1551 	[REGSET_SSVE] = { /* Streaming mode SVE */
1552 		.core_note_type = NT_ARM_SSVE,
1553 		.n = DIV_ROUND_UP(SVE_PT_SIZE(SME_VQ_MAX, SVE_PT_REGS_SVE),
1554 				  SVE_VQ_BYTES),
1555 		.size = SVE_VQ_BYTES,
1556 		.align = SVE_VQ_BYTES,
1557 		.regset_get = ssve_get,
1558 		.set = ssve_set,
1559 	},
1560 	[REGSET_ZA] = { /* SME ZA */
1561 		.core_note_type = NT_ARM_ZA,
1562 		/*
1563 		 * ZA is a single register but it's variably sized and
1564 		 * the ptrace core requires that the size of any data
1565 		 * be an exact multiple of the configured register
1566 		 * size so report as though we had SVE_VQ_BYTES
1567 		 * registers. These values aren't exposed to
1568 		 * userspace.
1569 		 */
1570 		.n = DIV_ROUND_UP(ZA_PT_SIZE(SME_VQ_MAX), SVE_VQ_BYTES),
1571 		.size = SVE_VQ_BYTES,
1572 		.align = SVE_VQ_BYTES,
1573 		.regset_get = za_get,
1574 		.set = za_set,
1575 	},
1576 	[REGSET_ZT] = { /* SME ZT */
1577 		.core_note_type = NT_ARM_ZT,
1578 		.n = 1,
1579 		.size = ZT_SIG_REG_BYTES,
1580 		.align = sizeof(u64),
1581 		.regset_get = zt_get,
1582 		.set = zt_set,
1583 	},
1584 #endif
1585 #ifdef CONFIG_ARM64_PTR_AUTH
1586 	[REGSET_PAC_MASK] = {
1587 		.core_note_type = NT_ARM_PAC_MASK,
1588 		.n = sizeof(struct user_pac_mask) / sizeof(u64),
1589 		.size = sizeof(u64),
1590 		.align = sizeof(u64),
1591 		.regset_get = pac_mask_get,
1592 		/* this cannot be set dynamically */
1593 	},
1594 	[REGSET_PAC_ENABLED_KEYS] = {
1595 		.core_note_type = NT_ARM_PAC_ENABLED_KEYS,
1596 		.n = 1,
1597 		.size = sizeof(long),
1598 		.align = sizeof(long),
1599 		.regset_get = pac_enabled_keys_get,
1600 		.set = pac_enabled_keys_set,
1601 	},
1602 #ifdef CONFIG_CHECKPOINT_RESTORE
1603 	[REGSET_PACA_KEYS] = {
1604 		.core_note_type = NT_ARM_PACA_KEYS,
1605 		.n = sizeof(struct user_pac_address_keys) / sizeof(__uint128_t),
1606 		.size = sizeof(__uint128_t),
1607 		.align = sizeof(__uint128_t),
1608 		.regset_get = pac_address_keys_get,
1609 		.set = pac_address_keys_set,
1610 	},
1611 	[REGSET_PACG_KEYS] = {
1612 		.core_note_type = NT_ARM_PACG_KEYS,
1613 		.n = sizeof(struct user_pac_generic_keys) / sizeof(__uint128_t),
1614 		.size = sizeof(__uint128_t),
1615 		.align = sizeof(__uint128_t),
1616 		.regset_get = pac_generic_keys_get,
1617 		.set = pac_generic_keys_set,
1618 	},
1619 #endif
1620 #endif
1621 #ifdef CONFIG_ARM64_TAGGED_ADDR_ABI
1622 	[REGSET_TAGGED_ADDR_CTRL] = {
1623 		.core_note_type = NT_ARM_TAGGED_ADDR_CTRL,
1624 		.n = 1,
1625 		.size = sizeof(long),
1626 		.align = sizeof(long),
1627 		.regset_get = tagged_addr_ctrl_get,
1628 		.set = tagged_addr_ctrl_set,
1629 	},
1630 #endif
1631 };
1632 
1633 static const struct user_regset_view user_aarch64_view = {
1634 	.name = "aarch64", .e_machine = EM_AARCH64,
1635 	.regsets = aarch64_regsets, .n = ARRAY_SIZE(aarch64_regsets)
1636 };
1637 
1638 enum compat_regset {
1639 	REGSET_COMPAT_GPR,
1640 	REGSET_COMPAT_VFP,
1641 };
1642 
1643 static inline compat_ulong_t compat_get_user_reg(struct task_struct *task, int idx)
1644 {
1645 	struct pt_regs *regs = task_pt_regs(task);
1646 
1647 	switch (idx) {
1648 	case 15:
1649 		return regs->pc;
1650 	case 16:
1651 		return pstate_to_compat_psr(regs->pstate);
1652 	case 17:
1653 		return regs->orig_x0;
1654 	default:
1655 		return regs->regs[idx];
1656 	}
1657 }
1658 
1659 static int compat_gpr_get(struct task_struct *target,
1660 			  const struct user_regset *regset,
1661 			  struct membuf to)
1662 {
1663 	int i = 0;
1664 
1665 	while (to.left)
1666 		membuf_store(&to, compat_get_user_reg(target, i++));
1667 	return 0;
1668 }
1669 
1670 static int compat_gpr_set(struct task_struct *target,
1671 			  const struct user_regset *regset,
1672 			  unsigned int pos, unsigned int count,
1673 			  const void *kbuf, const void __user *ubuf)
1674 {
1675 	struct pt_regs newregs;
1676 	int ret = 0;
1677 	unsigned int i, start, num_regs;
1678 
1679 	/* Calculate the number of AArch32 registers contained in count */
1680 	num_regs = count / regset->size;
1681 
1682 	/* Convert pos into an register number */
1683 	start = pos / regset->size;
1684 
1685 	if (start + num_regs > regset->n)
1686 		return -EIO;
1687 
1688 	newregs = *task_pt_regs(target);
1689 
1690 	for (i = 0; i < num_regs; ++i) {
1691 		unsigned int idx = start + i;
1692 		compat_ulong_t reg;
1693 
1694 		if (kbuf) {
1695 			memcpy(&reg, kbuf, sizeof(reg));
1696 			kbuf += sizeof(reg);
1697 		} else {
1698 			ret = copy_from_user(&reg, ubuf, sizeof(reg));
1699 			if (ret) {
1700 				ret = -EFAULT;
1701 				break;
1702 			}
1703 
1704 			ubuf += sizeof(reg);
1705 		}
1706 
1707 		switch (idx) {
1708 		case 15:
1709 			newregs.pc = reg;
1710 			break;
1711 		case 16:
1712 			reg = compat_psr_to_pstate(reg);
1713 			newregs.pstate = reg;
1714 			break;
1715 		case 17:
1716 			newregs.orig_x0 = reg;
1717 			break;
1718 		default:
1719 			newregs.regs[idx] = reg;
1720 		}
1721 
1722 	}
1723 
1724 	if (valid_user_regs(&newregs.user_regs, target))
1725 		*task_pt_regs(target) = newregs;
1726 	else
1727 		ret = -EINVAL;
1728 
1729 	return ret;
1730 }
1731 
1732 static int compat_vfp_get(struct task_struct *target,
1733 			  const struct user_regset *regset,
1734 			  struct membuf to)
1735 {
1736 	struct user_fpsimd_state *uregs;
1737 	compat_ulong_t fpscr;
1738 
1739 	if (!system_supports_fpsimd())
1740 		return -EINVAL;
1741 
1742 	uregs = &target->thread.uw.fpsimd_state;
1743 
1744 	if (target == current)
1745 		fpsimd_preserve_current_state();
1746 
1747 	/*
1748 	 * The VFP registers are packed into the fpsimd_state, so they all sit
1749 	 * nicely together for us. We just need to create the fpscr separately.
1750 	 */
1751 	membuf_write(&to, uregs, VFP_STATE_SIZE - sizeof(compat_ulong_t));
1752 	fpscr = (uregs->fpsr & VFP_FPSCR_STAT_MASK) |
1753 		(uregs->fpcr & VFP_FPSCR_CTRL_MASK);
1754 	return membuf_store(&to, fpscr);
1755 }
1756 
1757 static int compat_vfp_set(struct task_struct *target,
1758 			  const struct user_regset *regset,
1759 			  unsigned int pos, unsigned int count,
1760 			  const void *kbuf, const void __user *ubuf)
1761 {
1762 	struct user_fpsimd_state *uregs;
1763 	compat_ulong_t fpscr;
1764 	int ret, vregs_end_pos;
1765 
1766 	if (!system_supports_fpsimd())
1767 		return -EINVAL;
1768 
1769 	uregs = &target->thread.uw.fpsimd_state;
1770 
1771 	vregs_end_pos = VFP_STATE_SIZE - sizeof(compat_ulong_t);
1772 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
1773 				 vregs_end_pos);
1774 
1775 	if (count && !ret) {
1776 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fpscr,
1777 					 vregs_end_pos, VFP_STATE_SIZE);
1778 		if (!ret) {
1779 			uregs->fpsr = fpscr & VFP_FPSCR_STAT_MASK;
1780 			uregs->fpcr = fpscr & VFP_FPSCR_CTRL_MASK;
1781 		}
1782 	}
1783 
1784 	fpsimd_flush_task_state(target);
1785 	return ret;
1786 }
1787 
1788 static int compat_tls_get(struct task_struct *target,
1789 			  const struct user_regset *regset,
1790 			  struct membuf to)
1791 {
1792 	return membuf_store(&to, (compat_ulong_t)target->thread.uw.tp_value);
1793 }
1794 
1795 static int compat_tls_set(struct task_struct *target,
1796 			  const struct user_regset *regset, unsigned int pos,
1797 			  unsigned int count, const void *kbuf,
1798 			  const void __user *ubuf)
1799 {
1800 	int ret;
1801 	compat_ulong_t tls = target->thread.uw.tp_value;
1802 
1803 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tls, 0, -1);
1804 	if (ret)
1805 		return ret;
1806 
1807 	target->thread.uw.tp_value = tls;
1808 	return ret;
1809 }
1810 
1811 static const struct user_regset aarch32_regsets[] = {
1812 	[REGSET_COMPAT_GPR] = {
1813 		.core_note_type = NT_PRSTATUS,
1814 		.n = COMPAT_ELF_NGREG,
1815 		.size = sizeof(compat_elf_greg_t),
1816 		.align = sizeof(compat_elf_greg_t),
1817 		.regset_get = compat_gpr_get,
1818 		.set = compat_gpr_set
1819 	},
1820 	[REGSET_COMPAT_VFP] = {
1821 		.core_note_type = NT_ARM_VFP,
1822 		.n = VFP_STATE_SIZE / sizeof(compat_ulong_t),
1823 		.size = sizeof(compat_ulong_t),
1824 		.align = sizeof(compat_ulong_t),
1825 		.active = fpr_active,
1826 		.regset_get = compat_vfp_get,
1827 		.set = compat_vfp_set
1828 	},
1829 };
1830 
1831 static const struct user_regset_view user_aarch32_view = {
1832 	.name = "aarch32", .e_machine = EM_ARM,
1833 	.regsets = aarch32_regsets, .n = ARRAY_SIZE(aarch32_regsets)
1834 };
1835 
1836 static const struct user_regset aarch32_ptrace_regsets[] = {
1837 	[REGSET_GPR] = {
1838 		.core_note_type = NT_PRSTATUS,
1839 		.n = COMPAT_ELF_NGREG,
1840 		.size = sizeof(compat_elf_greg_t),
1841 		.align = sizeof(compat_elf_greg_t),
1842 		.regset_get = compat_gpr_get,
1843 		.set = compat_gpr_set
1844 	},
1845 	[REGSET_FPR] = {
1846 		.core_note_type = NT_ARM_VFP,
1847 		.n = VFP_STATE_SIZE / sizeof(compat_ulong_t),
1848 		.size = sizeof(compat_ulong_t),
1849 		.align = sizeof(compat_ulong_t),
1850 		.regset_get = compat_vfp_get,
1851 		.set = compat_vfp_set
1852 	},
1853 	[REGSET_TLS] = {
1854 		.core_note_type = NT_ARM_TLS,
1855 		.n = 1,
1856 		.size = sizeof(compat_ulong_t),
1857 		.align = sizeof(compat_ulong_t),
1858 		.regset_get = compat_tls_get,
1859 		.set = compat_tls_set,
1860 	},
1861 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1862 	[REGSET_HW_BREAK] = {
1863 		.core_note_type = NT_ARM_HW_BREAK,
1864 		.n = sizeof(struct user_hwdebug_state) / sizeof(u32),
1865 		.size = sizeof(u32),
1866 		.align = sizeof(u32),
1867 		.regset_get = hw_break_get,
1868 		.set = hw_break_set,
1869 	},
1870 	[REGSET_HW_WATCH] = {
1871 		.core_note_type = NT_ARM_HW_WATCH,
1872 		.n = sizeof(struct user_hwdebug_state) / sizeof(u32),
1873 		.size = sizeof(u32),
1874 		.align = sizeof(u32),
1875 		.regset_get = hw_break_get,
1876 		.set = hw_break_set,
1877 	},
1878 #endif
1879 	[REGSET_SYSTEM_CALL] = {
1880 		.core_note_type = NT_ARM_SYSTEM_CALL,
1881 		.n = 1,
1882 		.size = sizeof(int),
1883 		.align = sizeof(int),
1884 		.regset_get = system_call_get,
1885 		.set = system_call_set,
1886 	},
1887 };
1888 
1889 static const struct user_regset_view user_aarch32_ptrace_view = {
1890 	.name = "aarch32", .e_machine = EM_ARM,
1891 	.regsets = aarch32_ptrace_regsets, .n = ARRAY_SIZE(aarch32_ptrace_regsets)
1892 };
1893 
1894 #ifdef CONFIG_COMPAT
1895 static int compat_ptrace_read_user(struct task_struct *tsk, compat_ulong_t off,
1896 				   compat_ulong_t __user *ret)
1897 {
1898 	compat_ulong_t tmp;
1899 
1900 	if (off & 3)
1901 		return -EIO;
1902 
1903 	if (off == COMPAT_PT_TEXT_ADDR)
1904 		tmp = tsk->mm->start_code;
1905 	else if (off == COMPAT_PT_DATA_ADDR)
1906 		tmp = tsk->mm->start_data;
1907 	else if (off == COMPAT_PT_TEXT_END_ADDR)
1908 		tmp = tsk->mm->end_code;
1909 	else if (off < sizeof(compat_elf_gregset_t))
1910 		tmp = compat_get_user_reg(tsk, off >> 2);
1911 	else if (off >= COMPAT_USER_SZ)
1912 		return -EIO;
1913 	else
1914 		tmp = 0;
1915 
1916 	return put_user(tmp, ret);
1917 }
1918 
1919 static int compat_ptrace_write_user(struct task_struct *tsk, compat_ulong_t off,
1920 				    compat_ulong_t val)
1921 {
1922 	struct pt_regs newregs = *task_pt_regs(tsk);
1923 	unsigned int idx = off / 4;
1924 
1925 	if (off & 3 || off >= COMPAT_USER_SZ)
1926 		return -EIO;
1927 
1928 	if (off >= sizeof(compat_elf_gregset_t))
1929 		return 0;
1930 
1931 	switch (idx) {
1932 	case 15:
1933 		newregs.pc = val;
1934 		break;
1935 	case 16:
1936 		newregs.pstate = compat_psr_to_pstate(val);
1937 		break;
1938 	case 17:
1939 		newregs.orig_x0 = val;
1940 		break;
1941 	default:
1942 		newregs.regs[idx] = val;
1943 	}
1944 
1945 	if (!valid_user_regs(&newregs.user_regs, tsk))
1946 		return -EINVAL;
1947 
1948 	*task_pt_regs(tsk) = newregs;
1949 	return 0;
1950 }
1951 
1952 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1953 
1954 /*
1955  * Convert a virtual register number into an index for a thread_info
1956  * breakpoint array. Breakpoints are identified using positive numbers
1957  * whilst watchpoints are negative. The registers are laid out as pairs
1958  * of (address, control), each pair mapping to a unique hw_breakpoint struct.
1959  * Register 0 is reserved for describing resource information.
1960  */
1961 static int compat_ptrace_hbp_num_to_idx(compat_long_t num)
1962 {
1963 	return (abs(num) - 1) >> 1;
1964 }
1965 
1966 static int compat_ptrace_hbp_get_resource_info(u32 *kdata)
1967 {
1968 	u8 num_brps, num_wrps, debug_arch, wp_len;
1969 	u32 reg = 0;
1970 
1971 	num_brps	= hw_breakpoint_slots(TYPE_INST);
1972 	num_wrps	= hw_breakpoint_slots(TYPE_DATA);
1973 
1974 	debug_arch	= debug_monitors_arch();
1975 	wp_len		= 8;
1976 	reg		|= debug_arch;
1977 	reg		<<= 8;
1978 	reg		|= wp_len;
1979 	reg		<<= 8;
1980 	reg		|= num_wrps;
1981 	reg		<<= 8;
1982 	reg		|= num_brps;
1983 
1984 	*kdata = reg;
1985 	return 0;
1986 }
1987 
1988 static int compat_ptrace_hbp_get(unsigned int note_type,
1989 				 struct task_struct *tsk,
1990 				 compat_long_t num,
1991 				 u32 *kdata)
1992 {
1993 	u64 addr = 0;
1994 	u32 ctrl = 0;
1995 
1996 	int err, idx = compat_ptrace_hbp_num_to_idx(num);
1997 
1998 	if (num & 1) {
1999 		err = ptrace_hbp_get_addr(note_type, tsk, idx, &addr);
2000 		*kdata = (u32)addr;
2001 	} else {
2002 		err = ptrace_hbp_get_ctrl(note_type, tsk, idx, &ctrl);
2003 		*kdata = ctrl;
2004 	}
2005 
2006 	return err;
2007 }
2008 
2009 static int compat_ptrace_hbp_set(unsigned int note_type,
2010 				 struct task_struct *tsk,
2011 				 compat_long_t num,
2012 				 u32 *kdata)
2013 {
2014 	u64 addr;
2015 	u32 ctrl;
2016 
2017 	int err, idx = compat_ptrace_hbp_num_to_idx(num);
2018 
2019 	if (num & 1) {
2020 		addr = *kdata;
2021 		err = ptrace_hbp_set_addr(note_type, tsk, idx, addr);
2022 	} else {
2023 		ctrl = *kdata;
2024 		err = ptrace_hbp_set_ctrl(note_type, tsk, idx, ctrl);
2025 	}
2026 
2027 	return err;
2028 }
2029 
2030 static int compat_ptrace_gethbpregs(struct task_struct *tsk, compat_long_t num,
2031 				    compat_ulong_t __user *data)
2032 {
2033 	int ret;
2034 	u32 kdata;
2035 
2036 	/* Watchpoint */
2037 	if (num < 0) {
2038 		ret = compat_ptrace_hbp_get(NT_ARM_HW_WATCH, tsk, num, &kdata);
2039 	/* Resource info */
2040 	} else if (num == 0) {
2041 		ret = compat_ptrace_hbp_get_resource_info(&kdata);
2042 	/* Breakpoint */
2043 	} else {
2044 		ret = compat_ptrace_hbp_get(NT_ARM_HW_BREAK, tsk, num, &kdata);
2045 	}
2046 
2047 	if (!ret)
2048 		ret = put_user(kdata, data);
2049 
2050 	return ret;
2051 }
2052 
2053 static int compat_ptrace_sethbpregs(struct task_struct *tsk, compat_long_t num,
2054 				    compat_ulong_t __user *data)
2055 {
2056 	int ret;
2057 	u32 kdata = 0;
2058 
2059 	if (num == 0)
2060 		return 0;
2061 
2062 	ret = get_user(kdata, data);
2063 	if (ret)
2064 		return ret;
2065 
2066 	if (num < 0)
2067 		ret = compat_ptrace_hbp_set(NT_ARM_HW_WATCH, tsk, num, &kdata);
2068 	else
2069 		ret = compat_ptrace_hbp_set(NT_ARM_HW_BREAK, tsk, num, &kdata);
2070 
2071 	return ret;
2072 }
2073 #endif	/* CONFIG_HAVE_HW_BREAKPOINT */
2074 
2075 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
2076 			compat_ulong_t caddr, compat_ulong_t cdata)
2077 {
2078 	unsigned long addr = caddr;
2079 	unsigned long data = cdata;
2080 	void __user *datap = compat_ptr(data);
2081 	int ret;
2082 
2083 	switch (request) {
2084 		case PTRACE_PEEKUSR:
2085 			ret = compat_ptrace_read_user(child, addr, datap);
2086 			break;
2087 
2088 		case PTRACE_POKEUSR:
2089 			ret = compat_ptrace_write_user(child, addr, data);
2090 			break;
2091 
2092 		case COMPAT_PTRACE_GETREGS:
2093 			ret = copy_regset_to_user(child,
2094 						  &user_aarch32_view,
2095 						  REGSET_COMPAT_GPR,
2096 						  0, sizeof(compat_elf_gregset_t),
2097 						  datap);
2098 			break;
2099 
2100 		case COMPAT_PTRACE_SETREGS:
2101 			ret = copy_regset_from_user(child,
2102 						    &user_aarch32_view,
2103 						    REGSET_COMPAT_GPR,
2104 						    0, sizeof(compat_elf_gregset_t),
2105 						    datap);
2106 			break;
2107 
2108 		case COMPAT_PTRACE_GET_THREAD_AREA:
2109 			ret = put_user((compat_ulong_t)child->thread.uw.tp_value,
2110 				       (compat_ulong_t __user *)datap);
2111 			break;
2112 
2113 		case COMPAT_PTRACE_SET_SYSCALL:
2114 			task_pt_regs(child)->syscallno = data;
2115 			ret = 0;
2116 			break;
2117 
2118 		case COMPAT_PTRACE_GETVFPREGS:
2119 			ret = copy_regset_to_user(child,
2120 						  &user_aarch32_view,
2121 						  REGSET_COMPAT_VFP,
2122 						  0, VFP_STATE_SIZE,
2123 						  datap);
2124 			break;
2125 
2126 		case COMPAT_PTRACE_SETVFPREGS:
2127 			ret = copy_regset_from_user(child,
2128 						    &user_aarch32_view,
2129 						    REGSET_COMPAT_VFP,
2130 						    0, VFP_STATE_SIZE,
2131 						    datap);
2132 			break;
2133 
2134 #ifdef CONFIG_HAVE_HW_BREAKPOINT
2135 		case COMPAT_PTRACE_GETHBPREGS:
2136 			ret = compat_ptrace_gethbpregs(child, addr, datap);
2137 			break;
2138 
2139 		case COMPAT_PTRACE_SETHBPREGS:
2140 			ret = compat_ptrace_sethbpregs(child, addr, datap);
2141 			break;
2142 #endif
2143 
2144 		default:
2145 			ret = compat_ptrace_request(child, request, addr,
2146 						    data);
2147 			break;
2148 	}
2149 
2150 	return ret;
2151 }
2152 #endif /* CONFIG_COMPAT */
2153 
2154 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
2155 {
2156 	/*
2157 	 * Core dumping of 32-bit tasks or compat ptrace requests must use the
2158 	 * user_aarch32_view compatible with arm32. Native ptrace requests on
2159 	 * 32-bit children use an extended user_aarch32_ptrace_view to allow
2160 	 * access to the TLS register.
2161 	 */
2162 	if (is_compat_task())
2163 		return &user_aarch32_view;
2164 	else if (is_compat_thread(task_thread_info(task)))
2165 		return &user_aarch32_ptrace_view;
2166 
2167 	return &user_aarch64_view;
2168 }
2169 
2170 long arch_ptrace(struct task_struct *child, long request,
2171 		 unsigned long addr, unsigned long data)
2172 {
2173 	switch (request) {
2174 	case PTRACE_PEEKMTETAGS:
2175 	case PTRACE_POKEMTETAGS:
2176 		return mte_ptrace_copy_tags(child, request, addr, data);
2177 	}
2178 
2179 	return ptrace_request(child, request, addr, data);
2180 }
2181 
2182 enum ptrace_syscall_dir {
2183 	PTRACE_SYSCALL_ENTER = 0,
2184 	PTRACE_SYSCALL_EXIT,
2185 };
2186 
2187 static void report_syscall(struct pt_regs *regs, enum ptrace_syscall_dir dir)
2188 {
2189 	int regno;
2190 	unsigned long saved_reg;
2191 
2192 	/*
2193 	 * We have some ABI weirdness here in the way that we handle syscall
2194 	 * exit stops because we indicate whether or not the stop has been
2195 	 * signalled from syscall entry or syscall exit by clobbering a general
2196 	 * purpose register (ip/r12 for AArch32, x7 for AArch64) in the tracee
2197 	 * and restoring its old value after the stop. This means that:
2198 	 *
2199 	 * - Any writes by the tracer to this register during the stop are
2200 	 *   ignored/discarded.
2201 	 *
2202 	 * - The actual value of the register is not available during the stop,
2203 	 *   so the tracer cannot save it and restore it later.
2204 	 *
2205 	 * - Syscall stops behave differently to seccomp and pseudo-step traps
2206 	 *   (the latter do not nobble any registers).
2207 	 */
2208 	regno = (is_compat_task() ? 12 : 7);
2209 	saved_reg = regs->regs[regno];
2210 	regs->regs[regno] = dir;
2211 
2212 	if (dir == PTRACE_SYSCALL_ENTER) {
2213 		if (ptrace_report_syscall_entry(regs))
2214 			forget_syscall(regs);
2215 		regs->regs[regno] = saved_reg;
2216 	} else if (!test_thread_flag(TIF_SINGLESTEP)) {
2217 		ptrace_report_syscall_exit(regs, 0);
2218 		regs->regs[regno] = saved_reg;
2219 	} else {
2220 		regs->regs[regno] = saved_reg;
2221 
2222 		/*
2223 		 * Signal a pseudo-step exception since we are stepping but
2224 		 * tracer modifications to the registers may have rewound the
2225 		 * state machine.
2226 		 */
2227 		ptrace_report_syscall_exit(regs, 1);
2228 	}
2229 }
2230 
2231 int syscall_trace_enter(struct pt_regs *regs)
2232 {
2233 	unsigned long flags = read_thread_flags();
2234 
2235 	if (flags & (_TIF_SYSCALL_EMU | _TIF_SYSCALL_TRACE)) {
2236 		report_syscall(regs, PTRACE_SYSCALL_ENTER);
2237 		if (flags & _TIF_SYSCALL_EMU)
2238 			return NO_SYSCALL;
2239 	}
2240 
2241 	/* Do the secure computing after ptrace; failures should be fast. */
2242 	if (secure_computing() == -1)
2243 		return NO_SYSCALL;
2244 
2245 	if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
2246 		trace_sys_enter(regs, regs->syscallno);
2247 
2248 	audit_syscall_entry(regs->syscallno, regs->orig_x0, regs->regs[1],
2249 			    regs->regs[2], regs->regs[3]);
2250 
2251 	return regs->syscallno;
2252 }
2253 
2254 void syscall_trace_exit(struct pt_regs *regs)
2255 {
2256 	unsigned long flags = read_thread_flags();
2257 
2258 	audit_syscall_exit(regs);
2259 
2260 	if (flags & _TIF_SYSCALL_TRACEPOINT)
2261 		trace_sys_exit(regs, syscall_get_return_value(current, regs));
2262 
2263 	if (flags & (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP))
2264 		report_syscall(regs, PTRACE_SYSCALL_EXIT);
2265 
2266 	rseq_syscall(regs);
2267 }
2268 
2269 /*
2270  * SPSR_ELx bits which are always architecturally RES0 per ARM DDI 0487D.a.
2271  * We permit userspace to set SSBS (AArch64 bit 12, AArch32 bit 23) which is
2272  * not described in ARM DDI 0487D.a.
2273  * We treat PAN and UAO as RES0 bits, as they are meaningless at EL0, and may
2274  * be allocated an EL0 meaning in future.
2275  * Userspace cannot use these until they have an architectural meaning.
2276  * Note that this follows the SPSR_ELx format, not the AArch32 PSR format.
2277  * We also reserve IL for the kernel; SS is handled dynamically.
2278  */
2279 #define SPSR_EL1_AARCH64_RES0_BITS \
2280 	(GENMASK_ULL(63, 32) | GENMASK_ULL(27, 26) | GENMASK_ULL(23, 22) | \
2281 	 GENMASK_ULL(20, 13) | GENMASK_ULL(5, 5))
2282 #define SPSR_EL1_AARCH32_RES0_BITS \
2283 	(GENMASK_ULL(63, 32) | GENMASK_ULL(22, 22) | GENMASK_ULL(20, 20))
2284 
2285 static int valid_compat_regs(struct user_pt_regs *regs)
2286 {
2287 	regs->pstate &= ~SPSR_EL1_AARCH32_RES0_BITS;
2288 
2289 	if (!system_supports_mixed_endian_el0()) {
2290 		if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
2291 			regs->pstate |= PSR_AA32_E_BIT;
2292 		else
2293 			regs->pstate &= ~PSR_AA32_E_BIT;
2294 	}
2295 
2296 	if (user_mode(regs) && (regs->pstate & PSR_MODE32_BIT) &&
2297 	    (regs->pstate & PSR_AA32_A_BIT) == 0 &&
2298 	    (regs->pstate & PSR_AA32_I_BIT) == 0 &&
2299 	    (regs->pstate & PSR_AA32_F_BIT) == 0) {
2300 		return 1;
2301 	}
2302 
2303 	/*
2304 	 * Force PSR to a valid 32-bit EL0t, preserving the same bits as
2305 	 * arch/arm.
2306 	 */
2307 	regs->pstate &= PSR_AA32_N_BIT | PSR_AA32_Z_BIT |
2308 			PSR_AA32_C_BIT | PSR_AA32_V_BIT |
2309 			PSR_AA32_Q_BIT | PSR_AA32_IT_MASK |
2310 			PSR_AA32_GE_MASK | PSR_AA32_E_BIT |
2311 			PSR_AA32_T_BIT;
2312 	regs->pstate |= PSR_MODE32_BIT;
2313 
2314 	return 0;
2315 }
2316 
2317 static int valid_native_regs(struct user_pt_regs *regs)
2318 {
2319 	regs->pstate &= ~SPSR_EL1_AARCH64_RES0_BITS;
2320 
2321 	if (user_mode(regs) && !(regs->pstate & PSR_MODE32_BIT) &&
2322 	    (regs->pstate & PSR_D_BIT) == 0 &&
2323 	    (regs->pstate & PSR_A_BIT) == 0 &&
2324 	    (regs->pstate & PSR_I_BIT) == 0 &&
2325 	    (regs->pstate & PSR_F_BIT) == 0) {
2326 		return 1;
2327 	}
2328 
2329 	/* Force PSR to a valid 64-bit EL0t */
2330 	regs->pstate &= PSR_N_BIT | PSR_Z_BIT | PSR_C_BIT | PSR_V_BIT;
2331 
2332 	return 0;
2333 }
2334 
2335 /*
2336  * Are the current registers suitable for user mode? (used to maintain
2337  * security in signal handlers)
2338  */
2339 int valid_user_regs(struct user_pt_regs *regs, struct task_struct *task)
2340 {
2341 	/* https://lore.kernel.org/lkml/20191118131525.GA4180@willie-the-truck */
2342 	user_regs_reset_single_step(regs, task);
2343 
2344 	if (is_compat_thread(task_thread_info(task)))
2345 		return valid_compat_regs(regs);
2346 	else
2347 		return valid_native_regs(regs);
2348 }
2349