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
47struct 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
57static 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 */
103int 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 */
121static 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 */
137unsigned 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, addr: (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 */
156void 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 */
170static 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 */
206void 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(bp: 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(bp: t->debug.hbp_watch[i]);
221 t->debug.hbp_watch[i] = NULL;
222 }
223 }
224}
225
226void ptrace_hw_copy_thread(struct task_struct *tsk)
227{
228 memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
229}
230
231static 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(error: -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
252out:
253 return bp;
254}
255
256static 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
280out:
281 return err;
282}
283
284static 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(error: -EINVAL);
301 }
302
303 ptrace_breakpoint_init(attr: &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: &attr, triggered: ptrace_hbptriggered, NULL, tsk);
315 if (IS_ERR(ptr: bp))
316 return bp;
317
318 err = ptrace_hbp_set_event(note_type, tsk, idx, bp);
319 if (err)
320 return ERR_PTR(error: err);
321
322 return bp;
323}
324
325static 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(x86_len: ctrl, x86_type: &len, gen_len: &type, gen_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
359static 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
383static 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(ptr: bp))
391 return PTR_ERR(ptr: bp);
392
393 *ctrl = bp ? encode_ctrl_reg(counter_arch_bp(bp)->ctrl) : 0;
394 return 0;
395}
396
397static 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(ptr: bp))
405 return PTR_ERR(ptr: bp);
406
407 *addr = bp ? counter_arch_bp(bp)->address : 0;
408 return 0;
409}
410
411static 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
423static 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(ptr: bp)) {
435 err = PTR_ERR(ptr: 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: ctrl, attr: &attr);
442 if (err)
443 return err;
444
445 return modify_user_hw_breakpoint(bp, attr: &attr);
446}
447
448static 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(ptr: bp)) {
459 err = PTR_ERR(ptr: bp);
460 return err;
461 }
462
463 attr = bp->attr;
464 attr.bp_addr = addr;
465 err = modify_user_hw_breakpoint(bp, attr: &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
473static 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: &info);
484 if (ret)
485 return ret;
486
487 membuf_write(s: &to, v: &info, size: sizeof(info));
488 membuf_zero(s: &to, size: sizeof(u32));
489 /* (address, ctrl) registers */
490 while (to.left) {
491 ret = ptrace_hbp_get_addr(note_type, tsk: target, idx, addr: &addr);
492 if (ret)
493 return ret;
494 ret = ptrace_hbp_get_ctrl(note_type, tsk: target, idx, ctrl: &ctrl);
495 if (ret)
496 return ret;
497 membuf_store(&to, addr);
498 membuf_store(&to, ctrl);
499 membuf_zero(s: &to, size: sizeof(u32));
500 idx++;
501 }
502 return 0;
503}
504
505static 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: &pos, count: &count, kbuf: &kbuf, ubuf: &ubuf, start_pos: 0, end_pos: 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: &pos, count: &count, kbuf: &kbuf, ubuf: &ubuf, data: &addr,
525 start_pos: offset, end_pos: offset + PTRACE_HBP_ADDR_SZ);
526 if (ret)
527 return ret;
528 ret = ptrace_hbp_set_addr(note_type, tsk: 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: &pos, count: &count, kbuf: &kbuf, ubuf: &ubuf, data: &ctrl,
536 start_pos: offset, end_pos: offset + PTRACE_HBP_CTRL_SZ);
537 if (ret)
538 return ret;
539 ret = ptrace_hbp_set_ctrl(note_type, tsk: target, idx, uctrl: ctrl);
540 if (ret)
541 return ret;
542 offset += PTRACE_HBP_CTRL_SZ;
543
544 user_regset_copyin_ignore(pos: &pos, count: &count, kbuf: &kbuf, ubuf: &ubuf,
545 start_pos: offset, end_pos: 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
554static 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
562static 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: &pos, count: &count, kbuf: &kbuf, ubuf: &ubuf, data: &newregs, start_pos: 0, end_pos: -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
580static 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 */
590static 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
603static 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
615static 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: &pos, count: &count, kbuf: &kbuf, ubuf: &ubuf, data: &newstate,
633 start_pos, end_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
642static 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, start_pos: 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
661static 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(s: &to, size: sizeof(u64));
674
675 return ret;
676}
677
678static 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: &pos, count: &count, kbuf: &kbuf, ubuf: &ubuf, data: tls, start_pos: 0, end_pos: 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
700static 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
712static 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: &pos, count: &count, kbuf: &kbuf, ubuf: &ubuf, data: &fpmr, start_pos: 0, end_pos: 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
733static 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
740static 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: &pos, count: &count, kbuf: &kbuf, ubuf: &ubuf, data: &syscallno, start_pos: 0, end_pos: -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
758static 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
806static unsigned int sve_size_from_header(struct user_sve_header const *header)
807{
808 return ALIGN(header->size, SVE_VQ_BYTES);
809}
810
811static 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
863static 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
873static 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
1005out:
1006 fpsimd_flush_task_state(target);
1007 return ret;
1008}
1009
1010static 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
1026static 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
1036static 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
1048static 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
1097static 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
1177out:
1178 fpsimd_flush_task_state(target);
1179 return ret;
1180}
1181
1182static 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
1202static 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
1239static 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
1260static 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
1272static 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
1293static __uint128_t pac_key_to_user(const struct ptrauth_key *key)
1294{
1295 return (__uint128_t)key->hi << 64 | key->lo;
1296}
1297
1298static 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
1308static 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
1317static 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
1326static 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
1341static 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
1363static 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
1369static 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
1375static 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
1390static 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
1415static 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
1427static 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
1443enum 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
1474static 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
1633static 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
1638enum compat_regset {
1639 REGSET_COMPAT_GPR,
1640 REGSET_COMPAT_VFP,
1641};
1642
1643static 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
1659static 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
1670static 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(to: &reg, from: ubuf, n: 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
1732static 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
1757static 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: &pos, count: &count, kbuf: &kbuf, ubuf: &ubuf, data: uregs, start_pos: 0,
1773 end_pos: 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
1788static 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
1795static 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: &pos, count: &count, kbuf: &kbuf, ubuf: &ubuf, data: &tls, start_pos: 0, end_pos: -1);
1804 if (ret)
1805 return ret;
1806
1807 target->thread.uw.tp_value = tls;
1808 return ret;
1809}
1810
1811static 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
1831static 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
1836static 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
1889static 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
1895static 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(task: tsk, idx: 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
1919static 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 */
1961static int compat_ptrace_hbp_num_to_idx(compat_long_t num)
1962{
1963 return (abs(num) - 1) >> 1;
1964}
1965
1966static 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
1988static 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: &addr);
2000 *kdata = (u32)addr;
2001 } else {
2002 err = ptrace_hbp_get_ctrl(note_type, tsk, idx, ctrl: &ctrl);
2003 *kdata = ctrl;
2004 }
2005
2006 return err;
2007}
2008
2009static 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, uctrl: ctrl);
2025 }
2026
2027 return err;
2028}
2029
2030static 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: &kdata);
2039 /* Resource info */
2040 } else if (num == 0) {
2041 ret = compat_ptrace_hbp_get_resource_info(kdata: &kdata);
2042 /* Breakpoint */
2043 } else {
2044 ret = compat_ptrace_hbp_get(NT_ARM_HW_BREAK, tsk, num, kdata: &kdata);
2045 }
2046
2047 if (!ret)
2048 ret = put_user(kdata, data);
2049
2050 return ret;
2051}
2052
2053static 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: &kdata);
2068 else
2069 ret = compat_ptrace_hbp_set(NT_ARM_HW_BREAK, tsk, num, kdata: &kdata);
2070
2071 return ret;
2072}
2073#endif /* CONFIG_HAVE_HW_BREAKPOINT */
2074
2075long 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(uptr: data);
2081 int ret;
2082
2083 switch (request) {
2084 case PTRACE_PEEKUSR:
2085 ret = compat_ptrace_read_user(tsk: child, off: addr, ret: datap);
2086 break;
2087
2088 case PTRACE_POKEUSR:
2089 ret = compat_ptrace_write_user(tsk: child, off: addr, val: 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(tsk: child, num: addr, data: datap);
2137 break;
2138
2139 case COMPAT_PTRACE_SETHBPREGS:
2140 ret = compat_ptrace_sethbpregs(tsk: child, num: addr, data: 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
2154const 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
2170long 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
2182enum ptrace_syscall_dir {
2183 PTRACE_SYSCALL_ENTER = 0,
2184 PTRACE_SYSCALL_EXIT,
2185};
2186
2187static 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, step: 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, step: 1);
2228 }
2229}
2230
2231int 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, dir: 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, id: regs->syscallno);
2247
2248 audit_syscall_entry(major: regs->syscallno, a0: regs->orig_x0, a1: regs->regs[1],
2249 a2: regs->regs[2], a3: regs->regs[3]);
2250
2251 return regs->syscallno;
2252}
2253
2254void syscall_trace_exit(struct pt_regs *regs)
2255{
2256 unsigned long flags = read_thread_flags();
2257
2258 audit_syscall_exit(pt_regs: regs);
2259
2260 if (flags & _TIF_SYSCALL_TRACEPOINT)
2261 trace_sys_exit(regs, ret: syscall_get_return_value(current, regs));
2262
2263 if (flags & (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP))
2264 report_syscall(regs, dir: 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
2285static 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
2317static 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 */
2339int 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

source code of linux/arch/arm64/kernel/ptrace.c