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1/* By Ross Biro 1/23/92 */
2/*
3 * Pentium III FXSR, SSE support
4 * Gareth Hughes <gareth@valinux.com>, May 2000
5 */
6
7#include <linux/kernel.h>
8#include <linux/sched.h>
9#include <linux/sched/task_stack.h>
10#include <linux/mm.h>
11#include <linux/smp.h>
12#include <linux/errno.h>
13#include <linux/slab.h>
14#include <linux/ptrace.h>
15#include <linux/tracehook.h>
16#include <linux/user.h>
17#include <linux/elf.h>
18#include <linux/security.h>
19#include <linux/audit.h>
20#include <linux/seccomp.h>
21#include <linux/signal.h>
22#include <linux/perf_event.h>
23#include <linux/hw_breakpoint.h>
24#include <linux/rcupdate.h>
25#include <linux/export.h>
26#include <linux/context_tracking.h>
27
28#include <linux/uaccess.h>
29#include <asm/pgtable.h>
30#include <asm/processor.h>
31#include <asm/fpu/internal.h>
32#include <asm/fpu/signal.h>
33#include <asm/fpu/regset.h>
34#include <asm/debugreg.h>
35#include <asm/ldt.h>
36#include <asm/desc.h>
37#include <asm/prctl.h>
38#include <asm/proto.h>
39#include <asm/hw_breakpoint.h>
40#include <asm/traps.h>
41#include <asm/syscall.h>
42
43#include "tls.h"
44
45enum x86_regset {
46 REGSET_GENERAL,
47 REGSET_FP,
48 REGSET_XFP,
49 REGSET_IOPERM64 = REGSET_XFP,
50 REGSET_XSTATE,
51 REGSET_TLS,
52 REGSET_IOPERM32,
53};
54
55struct pt_regs_offset {
56 const char *name;
57 int offset;
58};
59
60#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
61#define REG_OFFSET_END {.name = NULL, .offset = 0}
62
63static const struct pt_regs_offset regoffset_table[] = {
64#ifdef CONFIG_X86_64
65 REG_OFFSET_NAME(r15),
66 REG_OFFSET_NAME(r14),
67 REG_OFFSET_NAME(r13),
68 REG_OFFSET_NAME(r12),
69 REG_OFFSET_NAME(r11),
70 REG_OFFSET_NAME(r10),
71 REG_OFFSET_NAME(r9),
72 REG_OFFSET_NAME(r8),
73#endif
74 REG_OFFSET_NAME(bx),
75 REG_OFFSET_NAME(cx),
76 REG_OFFSET_NAME(dx),
77 REG_OFFSET_NAME(si),
78 REG_OFFSET_NAME(di),
79 REG_OFFSET_NAME(bp),
80 REG_OFFSET_NAME(ax),
81#ifdef CONFIG_X86_32
82 REG_OFFSET_NAME(ds),
83 REG_OFFSET_NAME(es),
84 REG_OFFSET_NAME(fs),
85 REG_OFFSET_NAME(gs),
86#endif
87 REG_OFFSET_NAME(orig_ax),
88 REG_OFFSET_NAME(ip),
89 REG_OFFSET_NAME(cs),
90 REG_OFFSET_NAME(flags),
91 REG_OFFSET_NAME(sp),
92 REG_OFFSET_NAME(ss),
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 for (roff = regoffset_table; roff->name != NULL; roff++)
107 if (!strcmp(roff->name, name))
108 return roff->offset;
109 return -EINVAL;
110}
111
112/**
113 * regs_query_register_name() - query register name from its offset
114 * @offset: the offset of a register in struct pt_regs.
115 *
116 * regs_query_register_name() returns the name of a register from its
117 * offset in struct pt_regs. If the @offset is invalid, this returns NULL;
118 */
119const char *regs_query_register_name(unsigned int offset)
120{
121 const struct pt_regs_offset *roff;
122 for (roff = regoffset_table; roff->name != NULL; roff++)
123 if (roff->offset == offset)
124 return roff->name;
125 return NULL;
126}
127
128/*
129 * does not yet catch signals sent when the child dies.
130 * in exit.c or in signal.c.
131 */
132
133/*
134 * Determines which flags the user has access to [1 = access, 0 = no access].
135 */
136#define FLAG_MASK_32 ((unsigned long) \
137 (X86_EFLAGS_CF | X86_EFLAGS_PF | \
138 X86_EFLAGS_AF | X86_EFLAGS_ZF | \
139 X86_EFLAGS_SF | X86_EFLAGS_TF | \
140 X86_EFLAGS_DF | X86_EFLAGS_OF | \
141 X86_EFLAGS_RF | X86_EFLAGS_AC))
142
143/*
144 * Determines whether a value may be installed in a segment register.
145 */
146static inline bool invalid_selector(u16 value)
147{
148 return unlikely(value != 0 && (value & SEGMENT_RPL_MASK) != USER_RPL);
149}
150
151#ifdef CONFIG_X86_32
152
153#define FLAG_MASK FLAG_MASK_32
154
155/*
156 * X86_32 CPUs don't save ss and esp if the CPU is already in kernel mode
157 * when it traps. The previous stack will be directly underneath the saved
158 * registers, and 'sp/ss' won't even have been saved. Thus the '®s->sp'.
159 *
160 * Now, if the stack is empty, '®s->sp' is out of range. In this
161 * case we try to take the previous stack. To always return a non-null
162 * stack pointer we fall back to regs as stack if no previous stack
163 * exists.
164 *
165 * This is valid only for kernel mode traps.
166 */
167unsigned long kernel_stack_pointer(struct pt_regs *regs)
168{
169 unsigned long context = (unsigned long)regs & ~(THREAD_SIZE - 1);
170 unsigned long sp = (unsigned long)®s->sp;
171 u32 *prev_esp;
172
173 if (context == (sp & ~(THREAD_SIZE - 1)))
174 return sp;
175
176 prev_esp = (u32 *)(context);
177 if (*prev_esp)
178 return (unsigned long)*prev_esp;
179
180 return (unsigned long)regs;
181}
182EXPORT_SYMBOL_GPL(kernel_stack_pointer);
183
184static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long regno)
185{
186 BUILD_BUG_ON(offsetof(struct pt_regs, bx) != 0);
187 return ®s->bx + (regno >> 2);
188}
189
190static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
191{
192 /*
193 * Returning the value truncates it to 16 bits.
194 */
195 unsigned int retval;
196 if (offset != offsetof(struct user_regs_struct, gs))
197 retval = *pt_regs_access(task_pt_regs(task), offset);
198 else {
199 if (task == current)
200 retval = get_user_gs(task_pt_regs(task));
201 else
202 retval = task_user_gs(task);
203 }
204 return retval;
205}
206
207static int set_segment_reg(struct task_struct *task,
208 unsigned long offset, u16 value)
209{
210 /*
211 * The value argument was already truncated to 16 bits.
212 */
213 if (invalid_selector(value))
214 return -EIO;
215
216 /*
217 * For %cs and %ss we cannot permit a null selector.
218 * We can permit a bogus selector as long as it has USER_RPL.
219 * Null selectors are fine for other segment registers, but
220 * we will never get back to user mode with invalid %cs or %ss
221 * and will take the trap in iret instead. Much code relies
222 * on user_mode() to distinguish a user trap frame (which can
223 * safely use invalid selectors) from a kernel trap frame.
224 */
225 switch (offset) {
226 case offsetof(struct user_regs_struct, cs):
227 case offsetof(struct user_regs_struct, ss):
228 if (unlikely(value == 0))
229 return -EIO;
230
231 default:
232 *pt_regs_access(task_pt_regs(task), offset) = value;
233 break;
234
235 case offsetof(struct user_regs_struct, gs):
236 if (task == current)
237 set_user_gs(task_pt_regs(task), value);
238 else
239 task_user_gs(task) = value;
240 }
241
242 return 0;
243}
244
245#else /* CONFIG_X86_64 */
246
247#define FLAG_MASK (FLAG_MASK_32 | X86_EFLAGS_NT)
248
249static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long offset)
250{
251 BUILD_BUG_ON(offsetof(struct pt_regs, r15) != 0);
252 return ®s->r15 + (offset / sizeof(regs->r15));
253}
254
255static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
256{
257 /*
258 * Returning the value truncates it to 16 bits.
259 */
260 unsigned int seg;
261
262 switch (offset) {
263 case offsetof(struct user_regs_struct, fs):
264 if (task == current) {
265 /* Older gas can't assemble movq %?s,%r?? */
266 asm("movl %%fs,%0" : "=r" (seg));
267 return seg;
268 }
269 return task->thread.fsindex;
270 case offsetof(struct user_regs_struct, gs):
271 if (task == current) {
272 asm("movl %%gs,%0" : "=r" (seg));
273 return seg;
274 }
275 return task->thread.gsindex;
276 case offsetof(struct user_regs_struct, ds):
277 if (task == current) {
278 asm("movl %%ds,%0" : "=r" (seg));
279 return seg;
280 }
281 return task->thread.ds;
282 case offsetof(struct user_regs_struct, es):
283 if (task == current) {
284 asm("movl %%es,%0" : "=r" (seg));
285 return seg;
286 }
287 return task->thread.es;
288
289 case offsetof(struct user_regs_struct, cs):
290 case offsetof(struct user_regs_struct, ss):
291 break;
292 }
293 return *pt_regs_access(task_pt_regs(task), offset);
294}
295
296static int set_segment_reg(struct task_struct *task,
297 unsigned long offset, u16 value)
298{
299 /*
300 * The value argument was already truncated to 16 bits.
301 */
302 if (invalid_selector(value))
303 return -EIO;
304
305 switch (offset) {
306 case offsetof(struct user_regs_struct,fs):
307 task->thread.fsindex = value;
308 if (task == current)
309 loadsegment(fs, task->thread.fsindex);
310 break;
311 case offsetof(struct user_regs_struct,gs):
312 task->thread.gsindex = value;
313 if (task == current)
314 load_gs_index(task->thread.gsindex);
315 break;
316 case offsetof(struct user_regs_struct,ds):
317 task->thread.ds = value;
318 if (task == current)
319 loadsegment(ds, task->thread.ds);
320 break;
321 case offsetof(struct user_regs_struct,es):
322 task->thread.es = value;
323 if (task == current)
324 loadsegment(es, task->thread.es);
325 break;
326
327 /*
328 * Can't actually change these in 64-bit mode.
329 */
330 case offsetof(struct user_regs_struct,cs):
331 if (unlikely(value == 0))
332 return -EIO;
333 task_pt_regs(task)->cs = value;
334 break;
335 case offsetof(struct user_regs_struct,ss):
336 if (unlikely(value == 0))
337 return -EIO;
338 task_pt_regs(task)->ss = value;
339 break;
340 }
341
342 return 0;
343}
344
345#endif /* CONFIG_X86_32 */
346
347static unsigned long get_flags(struct task_struct *task)
348{
349 unsigned long retval = task_pt_regs(task)->flags;
350
351 /*
352 * If the debugger set TF, hide it from the readout.
353 */
354 if (test_tsk_thread_flag(task, TIF_FORCED_TF))
355 retval &= ~X86_EFLAGS_TF;
356
357 return retval;
358}
359
360static int set_flags(struct task_struct *task, unsigned long value)
361{
362 struct pt_regs *regs = task_pt_regs(task);
363
364 /*
365 * If the user value contains TF, mark that
366 * it was not "us" (the debugger) that set it.
367 * If not, make sure it stays set if we had.
368 */
369 if (value & X86_EFLAGS_TF)
370 clear_tsk_thread_flag(task, TIF_FORCED_TF);
371 else if (test_tsk_thread_flag(task, TIF_FORCED_TF))
372 value |= X86_EFLAGS_TF;
373
374 regs->flags = (regs->flags & ~FLAG_MASK) | (value & FLAG_MASK);
375
376 return 0;
377}
378
379static int putreg(struct task_struct *child,
380 unsigned long offset, unsigned long value)
381{
382 switch (offset) {
383 case offsetof(struct user_regs_struct, cs):
384 case offsetof(struct user_regs_struct, ds):
385 case offsetof(struct user_regs_struct, es):
386 case offsetof(struct user_regs_struct, fs):
387 case offsetof(struct user_regs_struct, gs):
388 case offsetof(struct user_regs_struct, ss):
389 return set_segment_reg(child, offset, value);
390
391 case offsetof(struct user_regs_struct, flags):
392 return set_flags(child, value);
393
394#ifdef CONFIG_X86_64
395 case offsetof(struct user_regs_struct,fs_base):
396 if (value >= TASK_SIZE_MAX)
397 return -EIO;
398 /*
399 * When changing the segment base, use do_arch_prctl_64
400 * to set either thread.fs or thread.fsindex and the
401 * corresponding GDT slot.
402 */
403 if (child->thread.fsbase != value)
404 return do_arch_prctl_64(child, ARCH_SET_FS, value);
405 return 0;
406 case offsetof(struct user_regs_struct,gs_base):
407 /*
408 * Exactly the same here as the %fs handling above.
409 */
410 if (value >= TASK_SIZE_MAX)
411 return -EIO;
412 if (child->thread.gsbase != value)
413 return do_arch_prctl_64(child, ARCH_SET_GS, value);
414 return 0;
415#endif
416 }
417
418 *pt_regs_access(task_pt_regs(child), offset) = value;
419 return 0;
420}
421
422static unsigned long getreg(struct task_struct *task, unsigned long offset)
423{
424 switch (offset) {
425 case offsetof(struct user_regs_struct, cs):
426 case offsetof(struct user_regs_struct, ds):
427 case offsetof(struct user_regs_struct, es):
428 case offsetof(struct user_regs_struct, fs):
429 case offsetof(struct user_regs_struct, gs):
430 case offsetof(struct user_regs_struct, ss):
431 return get_segment_reg(task, offset);
432
433 case offsetof(struct user_regs_struct, flags):
434 return get_flags(task);
435
436#ifdef CONFIG_X86_64
437 case offsetof(struct user_regs_struct, fs_base): {
438 /*
439 * XXX: This will not behave as expected if called on
440 * current or if fsindex != 0.
441 */
442 return task->thread.fsbase;
443 }
444 case offsetof(struct user_regs_struct, gs_base): {
445 /*
446 * XXX: This will not behave as expected if called on
447 * current or if fsindex != 0.
448 */
449 return task->thread.gsbase;
450 }
451#endif
452 }
453
454 return *pt_regs_access(task_pt_regs(task), offset);
455}
456
457static int genregs_get(struct task_struct *target,
458 const struct user_regset *regset,
459 unsigned int pos, unsigned int count,
460 void *kbuf, void __user *ubuf)
461{
462 if (kbuf) {
463 unsigned long *k = kbuf;
464 while (count >= sizeof(*k)) {
465 *k++ = getreg(target, pos);
466 count -= sizeof(*k);
467 pos += sizeof(*k);
468 }
469 } else {
470 unsigned long __user *u = ubuf;
471 while (count >= sizeof(*u)) {
472 if (__put_user(getreg(target, pos), u++))
473 return -EFAULT;
474 count -= sizeof(*u);
475 pos += sizeof(*u);
476 }
477 }
478
479 return 0;
480}
481
482static int genregs_set(struct task_struct *target,
483 const struct user_regset *regset,
484 unsigned int pos, unsigned int count,
485 const void *kbuf, const void __user *ubuf)
486{
487 int ret = 0;
488 if (kbuf) {
489 const unsigned long *k = kbuf;
490 while (count >= sizeof(*k) && !ret) {
491 ret = putreg(target, pos, *k++);
492 count -= sizeof(*k);
493 pos += sizeof(*k);
494 }
495 } else {
496 const unsigned long __user *u = ubuf;
497 while (count >= sizeof(*u) && !ret) {
498 unsigned long word;
499 ret = __get_user(word, u++);
500 if (ret)
501 break;
502 ret = putreg(target, pos, word);
503 count -= sizeof(*u);
504 pos += sizeof(*u);
505 }
506 }
507 return ret;
508}
509
510static void ptrace_triggered(struct perf_event *bp,
511 struct perf_sample_data *data,
512 struct pt_regs *regs)
513{
514 int i;
515 struct thread_struct *thread = &(current->thread);
516
517 /*
518 * Store in the virtual DR6 register the fact that the breakpoint
519 * was hit so the thread's debugger will see it.
520 */
521 for (i = 0; i < HBP_NUM; i++) {
522 if (thread->ptrace_bps[i] == bp)
523 break;
524 }
525
526 thread->debugreg6 |= (DR_TRAP0 << i);
527}
528
529/*
530 * Walk through every ptrace breakpoints for this thread and
531 * build the dr7 value on top of their attributes.
532 *
533 */
534static unsigned long ptrace_get_dr7(struct perf_event *bp[])
535{
536 int i;
537 int dr7 = 0;
538 struct arch_hw_breakpoint *info;
539
540 for (i = 0; i < HBP_NUM; i++) {
541 if (bp[i] && !bp[i]->attr.disabled) {
542 info = counter_arch_bp(bp[i]);
543 dr7 |= encode_dr7(i, info->len, info->type);
544 }
545 }
546
547 return dr7;
548}
549
550static int ptrace_fill_bp_fields(struct perf_event_attr *attr,
551 int len, int type, bool disabled)
552{
553 int err, bp_len, bp_type;
554
555 err = arch_bp_generic_fields(len, type, &bp_len, &bp_type);
556 if (!err) {
557 attr->bp_len = bp_len;
558 attr->bp_type = bp_type;
559 attr->disabled = disabled;
560 }
561
562 return err;
563}
564
565static struct perf_event *
566ptrace_register_breakpoint(struct task_struct *tsk, int len, int type,
567 unsigned long addr, bool disabled)
568{
569 struct perf_event_attr attr;
570 int err;
571
572 ptrace_breakpoint_init(&attr);
573 attr.bp_addr = addr;
574
575 err = ptrace_fill_bp_fields(&attr, len, type, disabled);
576 if (err)
577 return ERR_PTR(err);
578
579 return register_user_hw_breakpoint(&attr, ptrace_triggered,
580 NULL, tsk);
581}
582
583static int ptrace_modify_breakpoint(struct perf_event *bp, int len, int type,
584 int disabled)
585{
586 struct perf_event_attr attr = bp->attr;
587 int err;
588
589 err = ptrace_fill_bp_fields(&attr, len, type, disabled);
590 if (err)
591 return err;
592
593 return modify_user_hw_breakpoint(bp, &attr);
594}
595
596/*
597 * Handle ptrace writes to debug register 7.
598 */
599static int ptrace_write_dr7(struct task_struct *tsk, unsigned long data)
600{
601 struct thread_struct *thread = &tsk->thread;
602 unsigned long old_dr7;
603 bool second_pass = false;
604 int i, rc, ret = 0;
605
606 data &= ~DR_CONTROL_RESERVED;
607 old_dr7 = ptrace_get_dr7(thread->ptrace_bps);
608
609restore:
610 rc = 0;
611 for (i = 0; i < HBP_NUM; i++) {
612 unsigned len, type;
613 bool disabled = !decode_dr7(data, i, &len, &type);
614 struct perf_event *bp = thread->ptrace_bps[i];
615
616 if (!bp) {
617 if (disabled)
618 continue;
619
620 bp = ptrace_register_breakpoint(tsk,
621 len, type, 0, disabled);
622 if (IS_ERR(bp)) {
623 rc = PTR_ERR(bp);
624 break;
625 }
626
627 thread->ptrace_bps[i] = bp;
628 continue;
629 }
630
631 rc = ptrace_modify_breakpoint(bp, len, type, disabled);
632 if (rc)
633 break;
634 }
635
636 /* Restore if the first pass failed, second_pass shouldn't fail. */
637 if (rc && !WARN_ON(second_pass)) {
638 ret = rc;
639 data = old_dr7;
640 second_pass = true;
641 goto restore;
642 }
643
644 return ret;
645}
646
647/*
648 * Handle PTRACE_PEEKUSR calls for the debug register area.
649 */
650static unsigned long ptrace_get_debugreg(struct task_struct *tsk, int n)
651{
652 struct thread_struct *thread = &tsk->thread;
653 unsigned long val = 0;
654
655 if (n < HBP_NUM) {
656 struct perf_event *bp = thread->ptrace_bps[n];
657
658 if (bp)
659 val = bp->hw.info.address;
660 } else if (n == 6) {
661 val = thread->debugreg6;
662 } else if (n == 7) {
663 val = thread->ptrace_dr7;
664 }
665 return val;
666}
667
668static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr,
669 unsigned long addr)
670{
671 struct thread_struct *t = &tsk->thread;
672 struct perf_event *bp = t->ptrace_bps[nr];
673 int err = 0;
674
675 if (!bp) {
676 /*
677 * Put stub len and type to create an inactive but correct bp.
678 *
679 * CHECKME: the previous code returned -EIO if the addr wasn't
680 * a valid task virtual addr. The new one will return -EINVAL in
681 * this case.
682 * -EINVAL may be what we want for in-kernel breakpoints users,
683 * but -EIO looks better for ptrace, since we refuse a register
684 * writing for the user. And anyway this is the previous
685 * behaviour.
686 */
687 bp = ptrace_register_breakpoint(tsk,
688 X86_BREAKPOINT_LEN_1, X86_BREAKPOINT_WRITE,
689 addr, true);
690 if (IS_ERR(bp))
691 err = PTR_ERR(bp);
692 else
693 t->ptrace_bps[nr] = bp;
694 } else {
695 struct perf_event_attr attr = bp->attr;
696
697 attr.bp_addr = addr;
698 err = modify_user_hw_breakpoint(bp, &attr);
699 }
700
701 return err;
702}
703
704/*
705 * Handle PTRACE_POKEUSR calls for the debug register area.
706 */
707static int ptrace_set_debugreg(struct task_struct *tsk, int n,
708 unsigned long val)
709{
710 struct thread_struct *thread = &tsk->thread;
711 /* There are no DR4 or DR5 registers */
712 int rc = -EIO;
713
714 if (n < HBP_NUM) {
715 rc = ptrace_set_breakpoint_addr(tsk, n, val);
716 } else if (n == 6) {
717 thread->debugreg6 = val;
718 rc = 0;
719 } else if (n == 7) {
720 rc = ptrace_write_dr7(tsk, val);
721 if (!rc)
722 thread->ptrace_dr7 = val;
723 }
724 return rc;
725}
726
727/*
728 * These access the current or another (stopped) task's io permission
729 * bitmap for debugging or core dump.
730 */
731static int ioperm_active(struct task_struct *target,
732 const struct user_regset *regset)
733{
734 return target->thread.io_bitmap_max / regset->size;
735}
736
737static int ioperm_get(struct task_struct *target,
738 const struct user_regset *regset,
739 unsigned int pos, unsigned int count,
740 void *kbuf, void __user *ubuf)
741{
742 if (!target->thread.io_bitmap_ptr)
743 return -ENXIO;
744
745 return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
746 target->thread.io_bitmap_ptr,
747 0, IO_BITMAP_BYTES);
748}
749
750/*
751 * Called by kernel/ptrace.c when detaching..
752 *
753 * Make sure the single step bit is not set.
754 */
755void ptrace_disable(struct task_struct *child)
756{
757 user_disable_single_step(child);
758#ifdef TIF_SYSCALL_EMU
759 clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
760#endif
761}
762
763#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
764static const struct user_regset_view user_x86_32_view; /* Initialized below. */
765#endif
766
767long arch_ptrace(struct task_struct *child, long request,
768 unsigned long addr, unsigned long data)
769{
770 int ret;
771 unsigned long __user *datap = (unsigned long __user *)data;
772
773 switch (request) {
774 /* read the word at location addr in the USER area. */
775 case PTRACE_PEEKUSR: {
776 unsigned long tmp;
777
778 ret = -EIO;
779 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))
780 break;
781
782 tmp = 0; /* Default return condition */
783 if (addr < sizeof(struct user_regs_struct))
784 tmp = getreg(child, addr);
785 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
786 addr <= offsetof(struct user, u_debugreg[7])) {
787 addr -= offsetof(struct user, u_debugreg[0]);
788 tmp = ptrace_get_debugreg(child, addr / sizeof(data));
789 }
790 ret = put_user(tmp, datap);
791 break;
792 }
793
794 case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
795 ret = -EIO;
796 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))
797 break;
798
799 if (addr < sizeof(struct user_regs_struct))
800 ret = putreg(child, addr, data);
801 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
802 addr <= offsetof(struct user, u_debugreg[7])) {
803 addr -= offsetof(struct user, u_debugreg[0]);
804 ret = ptrace_set_debugreg(child,
805 addr / sizeof(data), data);
806 }
807 break;
808
809 case PTRACE_GETREGS: /* Get all gp regs from the child. */
810 return copy_regset_to_user(child,
811 task_user_regset_view(current),
812 REGSET_GENERAL,
813 0, sizeof(struct user_regs_struct),
814 datap);
815
816 case PTRACE_SETREGS: /* Set all gp regs in the child. */
817 return copy_regset_from_user(child,
818 task_user_regset_view(current),
819 REGSET_GENERAL,
820 0, sizeof(struct user_regs_struct),
821 datap);
822
823 case PTRACE_GETFPREGS: /* Get the child FPU state. */
824 return copy_regset_to_user(child,
825 task_user_regset_view(current),
826 REGSET_FP,
827 0, sizeof(struct user_i387_struct),
828 datap);
829
830 case PTRACE_SETFPREGS: /* Set the child FPU state. */
831 return copy_regset_from_user(child,
832 task_user_regset_view(current),
833 REGSET_FP,
834 0, sizeof(struct user_i387_struct),
835 datap);
836
837#ifdef CONFIG_X86_32
838 case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
839 return copy_regset_to_user(child, &user_x86_32_view,
840 REGSET_XFP,
841 0, sizeof(struct user_fxsr_struct),
842 datap) ? -EIO : 0;
843
844 case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
845 return copy_regset_from_user(child, &user_x86_32_view,
846 REGSET_XFP,
847 0, sizeof(struct user_fxsr_struct),
848 datap) ? -EIO : 0;
849#endif
850
851#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
852 case PTRACE_GET_THREAD_AREA:
853 if ((int) addr < 0)
854 return -EIO;
855 ret = do_get_thread_area(child, addr,
856 (struct user_desc __user *)data);
857 break;
858
859 case PTRACE_SET_THREAD_AREA:
860 if ((int) addr < 0)
861 return -EIO;
862 ret = do_set_thread_area(child, addr,
863 (struct user_desc __user *)data, 0);
864 break;
865#endif
866
867#ifdef CONFIG_X86_64
868 /* normal 64bit interface to access TLS data.
869 Works just like arch_prctl, except that the arguments
870 are reversed. */
871 case PTRACE_ARCH_PRCTL:
872 ret = do_arch_prctl_64(child, data, addr);
873 break;
874#endif
875
876 default:
877 ret = ptrace_request(child, request, addr, data);
878 break;
879 }
880
881 return ret;
882}
883
884#ifdef CONFIG_IA32_EMULATION
885
886#include <linux/compat.h>
887#include <linux/syscalls.h>
888#include <asm/ia32.h>
889#include <asm/user32.h>
890
891#define R32(l,q) \
892 case offsetof(struct user32, regs.l): \
893 regs->q = value; break
894
895#define SEG32(rs) \
896 case offsetof(struct user32, regs.rs): \
897 return set_segment_reg(child, \
898 offsetof(struct user_regs_struct, rs), \
899 value); \
900 break
901
902static int putreg32(struct task_struct *child, unsigned regno, u32 value)
903{
904 struct pt_regs *regs = task_pt_regs(child);
905
906 switch (regno) {
907
908 SEG32(cs);
909 SEG32(ds);
910 SEG32(es);
911 SEG32(fs);
912 SEG32(gs);
913 SEG32(ss);
914
915 R32(ebx, bx);
916 R32(ecx, cx);
917 R32(edx, dx);
918 R32(edi, di);
919 R32(esi, si);
920 R32(ebp, bp);
921 R32(eax, ax);
922 R32(eip, ip);
923 R32(esp, sp);
924
925 case offsetof(struct user32, regs.orig_eax):
926 /*
927 * Warning: bizarre corner case fixup here. A 32-bit
928 * debugger setting orig_eax to -1 wants to disable
929 * syscall restart. Make sure that the syscall
930 * restart code sign-extends orig_ax. Also make sure
931 * we interpret the -ERESTART* codes correctly if
932 * loaded into regs->ax in case the task is not
933 * actually still sitting at the exit from a 32-bit
934 * syscall with TS_COMPAT still set.
935 */
936 regs->orig_ax = value;
937 if (syscall_get_nr(child, regs) >= 0)
938 child->thread_info.status |= TS_I386_REGS_POKED;
939 break;
940
941 case offsetof(struct user32, regs.eflags):
942 return set_flags(child, value);
943
944 case offsetof(struct user32, u_debugreg[0]) ...
945 offsetof(struct user32, u_debugreg[7]):
946 regno -= offsetof(struct user32, u_debugreg[0]);
947 return ptrace_set_debugreg(child, regno / 4, value);
948
949 default:
950 if (regno > sizeof(struct user32) || (regno & 3))
951 return -EIO;
952
953 /*
954 * Other dummy fields in the virtual user structure
955 * are ignored
956 */
957 break;
958 }
959 return 0;
960}
961
962#undef R32
963#undef SEG32
964
965#define R32(l,q) \
966 case offsetof(struct user32, regs.l): \
967 *val = regs->q; break
968
969#define SEG32(rs) \
970 case offsetof(struct user32, regs.rs): \
971 *val = get_segment_reg(child, \
972 offsetof(struct user_regs_struct, rs)); \
973 break
974
975static int getreg32(struct task_struct *child, unsigned regno, u32 *val)
976{
977 struct pt_regs *regs = task_pt_regs(child);
978
979 switch (regno) {
980
981 SEG32(ds);
982 SEG32(es);
983 SEG32(fs);
984 SEG32(gs);
985
986 R32(cs, cs);
987 R32(ss, ss);
988 R32(ebx, bx);
989 R32(ecx, cx);
990 R32(edx, dx);
991 R32(edi, di);
992 R32(esi, si);
993 R32(ebp, bp);
994 R32(eax, ax);
995 R32(orig_eax, orig_ax);
996 R32(eip, ip);
997 R32(esp, sp);
998
999 case offsetof(struct user32, regs.eflags):
1000 *val = get_flags(child);
1001 break;
1002
1003 case offsetof(struct user32, u_debugreg[0]) ...
1004 offsetof(struct user32, u_debugreg[7]):
1005 regno -= offsetof(struct user32, u_debugreg[0]);
1006 *val = ptrace_get_debugreg(child, regno / 4);
1007 break;
1008
1009 default:
1010 if (regno > sizeof(struct user32) || (regno & 3))
1011 return -EIO;
1012
1013 /*
1014 * Other dummy fields in the virtual user structure
1015 * are ignored
1016 */
1017 *val = 0;
1018 break;
1019 }
1020 return 0;
1021}
1022
1023#undef R32
1024#undef SEG32
1025
1026static int genregs32_get(struct task_struct *target,
1027 const struct user_regset *regset,
1028 unsigned int pos, unsigned int count,
1029 void *kbuf, void __user *ubuf)
1030{
1031 if (kbuf) {
1032 compat_ulong_t *k = kbuf;
1033 while (count >= sizeof(*k)) {
1034 getreg32(target, pos, k++);
1035 count -= sizeof(*k);
1036 pos += sizeof(*k);
1037 }
1038 } else {
1039 compat_ulong_t __user *u = ubuf;
1040 while (count >= sizeof(*u)) {
1041 compat_ulong_t word;
1042 getreg32(target, pos, &word);
1043 if (__put_user(word, u++))
1044 return -EFAULT;
1045 count -= sizeof(*u);
1046 pos += sizeof(*u);
1047 }
1048 }
1049
1050 return 0;
1051}
1052
1053static int genregs32_set(struct task_struct *target,
1054 const struct user_regset *regset,
1055 unsigned int pos, unsigned int count,
1056 const void *kbuf, const void __user *ubuf)
1057{
1058 int ret = 0;
1059 if (kbuf) {
1060 const compat_ulong_t *k = kbuf;
1061 while (count >= sizeof(*k) && !ret) {
1062 ret = putreg32(target, pos, *k++);
1063 count -= sizeof(*k);
1064 pos += sizeof(*k);
1065 }
1066 } else {
1067 const compat_ulong_t __user *u = ubuf;
1068 while (count >= sizeof(*u) && !ret) {
1069 compat_ulong_t word;
1070 ret = __get_user(word, u++);
1071 if (ret)
1072 break;
1073 ret = putreg32(target, pos, word);
1074 count -= sizeof(*u);
1075 pos += sizeof(*u);
1076 }
1077 }
1078 return ret;
1079}
1080
1081static long ia32_arch_ptrace(struct task_struct *child, compat_long_t request,
1082 compat_ulong_t caddr, compat_ulong_t cdata)
1083{
1084 unsigned long addr = caddr;
1085 unsigned long data = cdata;
1086 void __user *datap = compat_ptr(data);
1087 int ret;
1088 __u32 val;
1089
1090 switch (request) {
1091 case PTRACE_PEEKUSR:
1092 ret = getreg32(child, addr, &val);
1093 if (ret == 0)
1094 ret = put_user(val, (__u32 __user *)datap);
1095 break;
1096
1097 case PTRACE_POKEUSR:
1098 ret = putreg32(child, addr, data);
1099 break;
1100
1101 case PTRACE_GETREGS: /* Get all gp regs from the child. */
1102 return copy_regset_to_user(child, &user_x86_32_view,
1103 REGSET_GENERAL,
1104 0, sizeof(struct user_regs_struct32),
1105 datap);
1106
1107 case PTRACE_SETREGS: /* Set all gp regs in the child. */
1108 return copy_regset_from_user(child, &user_x86_32_view,
1109 REGSET_GENERAL, 0,
1110 sizeof(struct user_regs_struct32),
1111 datap);
1112
1113 case PTRACE_GETFPREGS: /* Get the child FPU state. */
1114 return copy_regset_to_user(child, &user_x86_32_view,
1115 REGSET_FP, 0,
1116 sizeof(struct user_i387_ia32_struct),
1117 datap);
1118
1119 case PTRACE_SETFPREGS: /* Set the child FPU state. */
1120 return copy_regset_from_user(
1121 child, &user_x86_32_view, REGSET_FP,
1122 0, sizeof(struct user_i387_ia32_struct), datap);
1123
1124 case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
1125 return copy_regset_to_user(child, &user_x86_32_view,
1126 REGSET_XFP, 0,
1127 sizeof(struct user32_fxsr_struct),
1128 datap);
1129
1130 case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
1131 return copy_regset_from_user(child, &user_x86_32_view,
1132 REGSET_XFP, 0,
1133 sizeof(struct user32_fxsr_struct),
1134 datap);
1135
1136 case PTRACE_GET_THREAD_AREA:
1137 case PTRACE_SET_THREAD_AREA:
1138 return arch_ptrace(child, request, addr, data);
1139
1140 default:
1141 return compat_ptrace_request(child, request, addr, data);
1142 }
1143
1144 return ret;
1145}
1146#endif /* CONFIG_IA32_EMULATION */
1147
1148#ifdef CONFIG_X86_X32_ABI
1149static long x32_arch_ptrace(struct task_struct *child,
1150 compat_long_t request, compat_ulong_t caddr,
1151 compat_ulong_t cdata)
1152{
1153 unsigned long addr = caddr;
1154 unsigned long data = cdata;
1155 void __user *datap = compat_ptr(data);
1156 int ret;
1157
1158 switch (request) {
1159 /* Read 32bits at location addr in the USER area. Only allow
1160 to return the lower 32bits of segment and debug registers. */
1161 case PTRACE_PEEKUSR: {
1162 u32 tmp;
1163
1164 ret = -EIO;
1165 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user) ||
1166 addr < offsetof(struct user_regs_struct, cs))
1167 break;
1168
1169 tmp = 0; /* Default return condition */
1170 if (addr < sizeof(struct user_regs_struct))
1171 tmp = getreg(child, addr);
1172 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
1173 addr <= offsetof(struct user, u_debugreg[7])) {
1174 addr -= offsetof(struct user, u_debugreg[0]);
1175 tmp = ptrace_get_debugreg(child, addr / sizeof(data));
1176 }
1177 ret = put_user(tmp, (__u32 __user *)datap);
1178 break;
1179 }
1180
1181 /* Write the word at location addr in the USER area. Only allow
1182 to update segment and debug registers with the upper 32bits
1183 zero-extended. */
1184 case PTRACE_POKEUSR:
1185 ret = -EIO;
1186 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user) ||
1187 addr < offsetof(struct user_regs_struct, cs))
1188 break;
1189
1190 if (addr < sizeof(struct user_regs_struct))
1191 ret = putreg(child, addr, data);
1192 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
1193 addr <= offsetof(struct user, u_debugreg[7])) {
1194 addr -= offsetof(struct user, u_debugreg[0]);
1195 ret = ptrace_set_debugreg(child,
1196 addr / sizeof(data), data);
1197 }
1198 break;
1199
1200 case PTRACE_GETREGS: /* Get all gp regs from the child. */
1201 return copy_regset_to_user(child,
1202 task_user_regset_view(current),
1203 REGSET_GENERAL,
1204 0, sizeof(struct user_regs_struct),
1205 datap);
1206
1207 case PTRACE_SETREGS: /* Set all gp regs in the child. */
1208 return copy_regset_from_user(child,
1209 task_user_regset_view(current),
1210 REGSET_GENERAL,
1211 0, sizeof(struct user_regs_struct),
1212 datap);
1213
1214 case PTRACE_GETFPREGS: /* Get the child FPU state. */
1215 return copy_regset_to_user(child,
1216 task_user_regset_view(current),
1217 REGSET_FP,
1218 0, sizeof(struct user_i387_struct),
1219 datap);
1220
1221 case PTRACE_SETFPREGS: /* Set the child FPU state. */
1222 return copy_regset_from_user(child,
1223 task_user_regset_view(current),
1224 REGSET_FP,
1225 0, sizeof(struct user_i387_struct),
1226 datap);
1227
1228 default:
1229 return compat_ptrace_request(child, request, addr, data);
1230 }
1231
1232 return ret;
1233}
1234#endif
1235
1236#ifdef CONFIG_COMPAT
1237long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
1238 compat_ulong_t caddr, compat_ulong_t cdata)
1239{
1240#ifdef CONFIG_X86_X32_ABI
1241 if (!in_ia32_syscall())
1242 return x32_arch_ptrace(child, request, caddr, cdata);
1243#endif
1244#ifdef CONFIG_IA32_EMULATION
1245 return ia32_arch_ptrace(child, request, caddr, cdata);
1246#else
1247 return 0;
1248#endif
1249}
1250#endif /* CONFIG_COMPAT */
1251
1252#ifdef CONFIG_X86_64
1253
1254static struct user_regset x86_64_regsets[] __ro_after_init = {
1255 [REGSET_GENERAL] = {
1256 .core_note_type = NT_PRSTATUS,
1257 .n = sizeof(struct user_regs_struct) / sizeof(long),
1258 .size = sizeof(long), .align = sizeof(long),
1259 .get = genregs_get, .set = genregs_set
1260 },
1261 [REGSET_FP] = {
1262 .core_note_type = NT_PRFPREG,
1263 .n = sizeof(struct user_i387_struct) / sizeof(long),
1264 .size = sizeof(long), .align = sizeof(long),
1265 .active = regset_xregset_fpregs_active, .get = xfpregs_get, .set = xfpregs_set
1266 },
1267 [REGSET_XSTATE] = {
1268 .core_note_type = NT_X86_XSTATE,
1269 .size = sizeof(u64), .align = sizeof(u64),
1270 .active = xstateregs_active, .get = xstateregs_get,
1271 .set = xstateregs_set
1272 },
1273 [REGSET_IOPERM64] = {
1274 .core_note_type = NT_386_IOPERM,
1275 .n = IO_BITMAP_LONGS,
1276 .size = sizeof(long), .align = sizeof(long),
1277 .active = ioperm_active, .get = ioperm_get
1278 },
1279};
1280
1281static const struct user_regset_view user_x86_64_view = {
1282 .name = "x86_64", .e_machine = EM_X86_64,
1283 .regsets = x86_64_regsets, .n = ARRAY_SIZE(x86_64_regsets)
1284};
1285
1286#else /* CONFIG_X86_32 */
1287
1288#define user_regs_struct32 user_regs_struct
1289#define genregs32_get genregs_get
1290#define genregs32_set genregs_set
1291
1292#endif /* CONFIG_X86_64 */
1293
1294#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1295static struct user_regset x86_32_regsets[] __ro_after_init = {
1296 [REGSET_GENERAL] = {
1297 .core_note_type = NT_PRSTATUS,
1298 .n = sizeof(struct user_regs_struct32) / sizeof(u32),
1299 .size = sizeof(u32), .align = sizeof(u32),
1300 .get = genregs32_get, .set = genregs32_set
1301 },
1302 [REGSET_FP] = {
1303 .core_note_type = NT_PRFPREG,
1304 .n = sizeof(struct user_i387_ia32_struct) / sizeof(u32),
1305 .size = sizeof(u32), .align = sizeof(u32),
1306 .active = regset_fpregs_active, .get = fpregs_get, .set = fpregs_set
1307 },
1308 [REGSET_XFP] = {
1309 .core_note_type = NT_PRXFPREG,
1310 .n = sizeof(struct user32_fxsr_struct) / sizeof(u32),
1311 .size = sizeof(u32), .align = sizeof(u32),
1312 .active = regset_xregset_fpregs_active, .get = xfpregs_get, .set = xfpregs_set
1313 },
1314 [REGSET_XSTATE] = {
1315 .core_note_type = NT_X86_XSTATE,
1316 .size = sizeof(u64), .align = sizeof(u64),
1317 .active = xstateregs_active, .get = xstateregs_get,
1318 .set = xstateregs_set
1319 },
1320 [REGSET_TLS] = {
1321 .core_note_type = NT_386_TLS,
1322 .n = GDT_ENTRY_TLS_ENTRIES, .bias = GDT_ENTRY_TLS_MIN,
1323 .size = sizeof(struct user_desc),
1324 .align = sizeof(struct user_desc),
1325 .active = regset_tls_active,
1326 .get = regset_tls_get, .set = regset_tls_set
1327 },
1328 [REGSET_IOPERM32] = {
1329 .core_note_type = NT_386_IOPERM,
1330 .n = IO_BITMAP_BYTES / sizeof(u32),
1331 .size = sizeof(u32), .align = sizeof(u32),
1332 .active = ioperm_active, .get = ioperm_get
1333 },
1334};
1335
1336static const struct user_regset_view user_x86_32_view = {
1337 .name = "i386", .e_machine = EM_386,
1338 .regsets = x86_32_regsets, .n = ARRAY_SIZE(x86_32_regsets)
1339};
1340#endif
1341
1342/*
1343 * This represents bytes 464..511 in the memory layout exported through
1344 * the REGSET_XSTATE interface.
1345 */
1346u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
1347
1348void __init update_regset_xstate_info(unsigned int size, u64 xstate_mask)
1349{
1350#ifdef CONFIG_X86_64
1351 x86_64_regsets[REGSET_XSTATE].n = size / sizeof(u64);
1352#endif
1353#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1354 x86_32_regsets[REGSET_XSTATE].n = size / sizeof(u64);
1355#endif
1356 xstate_fx_sw_bytes[USER_XSTATE_XCR0_WORD] = xstate_mask;
1357}
1358
1359const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1360{
1361#ifdef CONFIG_IA32_EMULATION
1362 if (!user_64bit_mode(task_pt_regs(task)))
1363#endif
1364#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1365 return &user_x86_32_view;
1366#endif
1367#ifdef CONFIG_X86_64
1368 return &user_x86_64_view;
1369#endif
1370}
1371
1372static void fill_sigtrap_info(struct task_struct *tsk,
1373 struct pt_regs *regs,
1374 int error_code, int si_code,
1375 struct siginfo *info)
1376{
1377 tsk->thread.trap_nr = X86_TRAP_DB;
1378 tsk->thread.error_code = error_code;
1379
1380 memset(info, 0, sizeof(*info));
1381 info->si_signo = SIGTRAP;
1382 info->si_code = si_code;
1383 info->si_addr = user_mode(regs) ? (void __user *)regs->ip : NULL;
1384}
1385
1386void user_single_step_siginfo(struct task_struct *tsk,
1387 struct pt_regs *regs,
1388 struct siginfo *info)
1389{
1390 fill_sigtrap_info(tsk, regs, 0, TRAP_BRKPT, info);
1391}
1392
1393void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs,
1394 int error_code, int si_code)
1395{
1396 struct siginfo info;
1397
1398 fill_sigtrap_info(tsk, regs, error_code, si_code, &info);
1399 /* Send us the fake SIGTRAP */
1400 force_sig_info(SIGTRAP, &info, tsk);
1401}
1// SPDX-License-Identifier: GPL-2.0-only
2/* By Ross Biro 1/23/92 */
3/*
4 * Pentium III FXSR, SSE support
5 * Gareth Hughes <gareth@valinux.com>, May 2000
6 */
7
8#include <linux/kernel.h>
9#include <linux/sched.h>
10#include <linux/sched/task_stack.h>
11#include <linux/mm.h>
12#include <linux/smp.h>
13#include <linux/errno.h>
14#include <linux/slab.h>
15#include <linux/ptrace.h>
16#include <linux/user.h>
17#include <linux/elf.h>
18#include <linux/security.h>
19#include <linux/audit.h>
20#include <linux/seccomp.h>
21#include <linux/signal.h>
22#include <linux/perf_event.h>
23#include <linux/hw_breakpoint.h>
24#include <linux/rcupdate.h>
25#include <linux/export.h>
26#include <linux/context_tracking.h>
27#include <linux/nospec.h>
28
29#include <linux/uaccess.h>
30#include <asm/processor.h>
31#include <asm/fpu/signal.h>
32#include <asm/fpu/regset.h>
33#include <asm/fpu/xstate.h>
34#include <asm/debugreg.h>
35#include <asm/ldt.h>
36#include <asm/desc.h>
37#include <asm/prctl.h>
38#include <asm/proto.h>
39#include <asm/hw_breakpoint.h>
40#include <asm/traps.h>
41#include <asm/syscall.h>
42#include <asm/fsgsbase.h>
43#include <asm/io_bitmap.h>
44
45#include "tls.h"
46
47enum x86_regset_32 {
48 REGSET32_GENERAL,
49 REGSET32_FP,
50 REGSET32_XFP,
51 REGSET32_XSTATE,
52 REGSET32_TLS,
53 REGSET32_IOPERM,
54};
55
56enum x86_regset_64 {
57 REGSET64_GENERAL,
58 REGSET64_FP,
59 REGSET64_IOPERM,
60 REGSET64_XSTATE,
61};
62
63#define REGSET_GENERAL \
64({ \
65 BUILD_BUG_ON((int)REGSET32_GENERAL != (int)REGSET64_GENERAL); \
66 REGSET32_GENERAL; \
67})
68
69#define REGSET_FP \
70({ \
71 BUILD_BUG_ON((int)REGSET32_FP != (int)REGSET64_FP); \
72 REGSET32_FP; \
73})
74
75
76struct pt_regs_offset {
77 const char *name;
78 int offset;
79};
80
81#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
82#define REG_OFFSET_END {.name = NULL, .offset = 0}
83
84static const struct pt_regs_offset regoffset_table[] = {
85#ifdef CONFIG_X86_64
86 REG_OFFSET_NAME(r15),
87 REG_OFFSET_NAME(r14),
88 REG_OFFSET_NAME(r13),
89 REG_OFFSET_NAME(r12),
90 REG_OFFSET_NAME(r11),
91 REG_OFFSET_NAME(r10),
92 REG_OFFSET_NAME(r9),
93 REG_OFFSET_NAME(r8),
94#endif
95 REG_OFFSET_NAME(bx),
96 REG_OFFSET_NAME(cx),
97 REG_OFFSET_NAME(dx),
98 REG_OFFSET_NAME(si),
99 REG_OFFSET_NAME(di),
100 REG_OFFSET_NAME(bp),
101 REG_OFFSET_NAME(ax),
102#ifdef CONFIG_X86_32
103 REG_OFFSET_NAME(ds),
104 REG_OFFSET_NAME(es),
105 REG_OFFSET_NAME(fs),
106 REG_OFFSET_NAME(gs),
107#endif
108 REG_OFFSET_NAME(orig_ax),
109 REG_OFFSET_NAME(ip),
110 REG_OFFSET_NAME(cs),
111 REG_OFFSET_NAME(flags),
112 REG_OFFSET_NAME(sp),
113 REG_OFFSET_NAME(ss),
114 REG_OFFSET_END,
115};
116
117/**
118 * regs_query_register_offset() - query register offset from its name
119 * @name: the name of a register
120 *
121 * regs_query_register_offset() returns the offset of a register in struct
122 * pt_regs from its name. If the name is invalid, this returns -EINVAL;
123 */
124int regs_query_register_offset(const char *name)
125{
126 const struct pt_regs_offset *roff;
127 for (roff = regoffset_table; roff->name != NULL; roff++)
128 if (!strcmp(roff->name, name))
129 return roff->offset;
130 return -EINVAL;
131}
132
133/**
134 * regs_query_register_name() - query register name from its offset
135 * @offset: the offset of a register in struct pt_regs.
136 *
137 * regs_query_register_name() returns the name of a register from its
138 * offset in struct pt_regs. If the @offset is invalid, this returns NULL;
139 */
140const char *regs_query_register_name(unsigned int offset)
141{
142 const struct pt_regs_offset *roff;
143 for (roff = regoffset_table; roff->name != NULL; roff++)
144 if (roff->offset == offset)
145 return roff->name;
146 return NULL;
147}
148
149/*
150 * does not yet catch signals sent when the child dies.
151 * in exit.c or in signal.c.
152 */
153
154/*
155 * Determines which flags the user has access to [1 = access, 0 = no access].
156 */
157#define FLAG_MASK_32 ((unsigned long) \
158 (X86_EFLAGS_CF | X86_EFLAGS_PF | \
159 X86_EFLAGS_AF | X86_EFLAGS_ZF | \
160 X86_EFLAGS_SF | X86_EFLAGS_TF | \
161 X86_EFLAGS_DF | X86_EFLAGS_OF | \
162 X86_EFLAGS_RF | X86_EFLAGS_AC))
163
164/*
165 * Determines whether a value may be installed in a segment register.
166 */
167static inline bool invalid_selector(u16 value)
168{
169 return unlikely(value != 0 && (value & SEGMENT_RPL_MASK) != USER_RPL);
170}
171
172#ifdef CONFIG_X86_32
173
174#define FLAG_MASK FLAG_MASK_32
175
176static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long regno)
177{
178 BUILD_BUG_ON(offsetof(struct pt_regs, bx) != 0);
179 return ®s->bx + (regno >> 2);
180}
181
182static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
183{
184 /*
185 * Returning the value truncates it to 16 bits.
186 */
187 unsigned int retval;
188 if (offset != offsetof(struct user_regs_struct, gs))
189 retval = *pt_regs_access(task_pt_regs(task), offset);
190 else {
191 if (task == current)
192 savesegment(gs, retval);
193 else
194 retval = task->thread.gs;
195 }
196 return retval;
197}
198
199static int set_segment_reg(struct task_struct *task,
200 unsigned long offset, u16 value)
201{
202 if (WARN_ON_ONCE(task == current))
203 return -EIO;
204
205 /*
206 * The value argument was already truncated to 16 bits.
207 */
208 if (invalid_selector(value))
209 return -EIO;
210
211 /*
212 * For %cs and %ss we cannot permit a null selector.
213 * We can permit a bogus selector as long as it has USER_RPL.
214 * Null selectors are fine for other segment registers, but
215 * we will never get back to user mode with invalid %cs or %ss
216 * and will take the trap in iret instead. Much code relies
217 * on user_mode() to distinguish a user trap frame (which can
218 * safely use invalid selectors) from a kernel trap frame.
219 */
220 switch (offset) {
221 case offsetof(struct user_regs_struct, cs):
222 case offsetof(struct user_regs_struct, ss):
223 if (unlikely(value == 0))
224 return -EIO;
225 fallthrough;
226
227 default:
228 *pt_regs_access(task_pt_regs(task), offset) = value;
229 break;
230
231 case offsetof(struct user_regs_struct, gs):
232 task->thread.gs = value;
233 }
234
235 return 0;
236}
237
238#else /* CONFIG_X86_64 */
239
240#define FLAG_MASK (FLAG_MASK_32 | X86_EFLAGS_NT)
241
242static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long offset)
243{
244 BUILD_BUG_ON(offsetof(struct pt_regs, r15) != 0);
245 return ®s->r15 + (offset / sizeof(regs->r15));
246}
247
248static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
249{
250 /*
251 * Returning the value truncates it to 16 bits.
252 */
253 unsigned int seg;
254
255 switch (offset) {
256 case offsetof(struct user_regs_struct, fs):
257 if (task == current) {
258 /* Older gas can't assemble movq %?s,%r?? */
259 asm("movl %%fs,%0" : "=r" (seg));
260 return seg;
261 }
262 return task->thread.fsindex;
263 case offsetof(struct user_regs_struct, gs):
264 if (task == current) {
265 asm("movl %%gs,%0" : "=r" (seg));
266 return seg;
267 }
268 return task->thread.gsindex;
269 case offsetof(struct user_regs_struct, ds):
270 if (task == current) {
271 asm("movl %%ds,%0" : "=r" (seg));
272 return seg;
273 }
274 return task->thread.ds;
275 case offsetof(struct user_regs_struct, es):
276 if (task == current) {
277 asm("movl %%es,%0" : "=r" (seg));
278 return seg;
279 }
280 return task->thread.es;
281
282 case offsetof(struct user_regs_struct, cs):
283 case offsetof(struct user_regs_struct, ss):
284 break;
285 }
286 return *pt_regs_access(task_pt_regs(task), offset);
287}
288
289static int set_segment_reg(struct task_struct *task,
290 unsigned long offset, u16 value)
291{
292 if (WARN_ON_ONCE(task == current))
293 return -EIO;
294
295 /*
296 * The value argument was already truncated to 16 bits.
297 */
298 if (invalid_selector(value))
299 return -EIO;
300
301 /*
302 * Writes to FS and GS will change the stored selector. Whether
303 * this changes the segment base as well depends on whether
304 * FSGSBASE is enabled.
305 */
306
307 switch (offset) {
308 case offsetof(struct user_regs_struct,fs):
309 task->thread.fsindex = value;
310 break;
311 case offsetof(struct user_regs_struct,gs):
312 task->thread.gsindex = value;
313 break;
314 case offsetof(struct user_regs_struct,ds):
315 task->thread.ds = value;
316 break;
317 case offsetof(struct user_regs_struct,es):
318 task->thread.es = value;
319 break;
320
321 /*
322 * Can't actually change these in 64-bit mode.
323 */
324 case offsetof(struct user_regs_struct,cs):
325 if (unlikely(value == 0))
326 return -EIO;
327 task_pt_regs(task)->cs = value;
328 break;
329 case offsetof(struct user_regs_struct,ss):
330 if (unlikely(value == 0))
331 return -EIO;
332 task_pt_regs(task)->ss = value;
333 break;
334 }
335
336 return 0;
337}
338
339#endif /* CONFIG_X86_32 */
340
341static unsigned long get_flags(struct task_struct *task)
342{
343 unsigned long retval = task_pt_regs(task)->flags;
344
345 /*
346 * If the debugger set TF, hide it from the readout.
347 */
348 if (test_tsk_thread_flag(task, TIF_FORCED_TF))
349 retval &= ~X86_EFLAGS_TF;
350
351 return retval;
352}
353
354static int set_flags(struct task_struct *task, unsigned long value)
355{
356 struct pt_regs *regs = task_pt_regs(task);
357
358 /*
359 * If the user value contains TF, mark that
360 * it was not "us" (the debugger) that set it.
361 * If not, make sure it stays set if we had.
362 */
363 if (value & X86_EFLAGS_TF)
364 clear_tsk_thread_flag(task, TIF_FORCED_TF);
365 else if (test_tsk_thread_flag(task, TIF_FORCED_TF))
366 value |= X86_EFLAGS_TF;
367
368 regs->flags = (regs->flags & ~FLAG_MASK) | (value & FLAG_MASK);
369
370 return 0;
371}
372
373static int putreg(struct task_struct *child,
374 unsigned long offset, unsigned long value)
375{
376 switch (offset) {
377 case offsetof(struct user_regs_struct, cs):
378 case offsetof(struct user_regs_struct, ds):
379 case offsetof(struct user_regs_struct, es):
380 case offsetof(struct user_regs_struct, fs):
381 case offsetof(struct user_regs_struct, gs):
382 case offsetof(struct user_regs_struct, ss):
383 return set_segment_reg(child, offset, value);
384
385 case offsetof(struct user_regs_struct, flags):
386 return set_flags(child, value);
387
388#ifdef CONFIG_X86_64
389 case offsetof(struct user_regs_struct,fs_base):
390 if (value >= TASK_SIZE_MAX)
391 return -EIO;
392 x86_fsbase_write_task(child, value);
393 return 0;
394 case offsetof(struct user_regs_struct,gs_base):
395 if (value >= TASK_SIZE_MAX)
396 return -EIO;
397 x86_gsbase_write_task(child, value);
398 return 0;
399#endif
400 }
401
402 *pt_regs_access(task_pt_regs(child), offset) = value;
403 return 0;
404}
405
406static unsigned long getreg(struct task_struct *task, unsigned long offset)
407{
408 switch (offset) {
409 case offsetof(struct user_regs_struct, cs):
410 case offsetof(struct user_regs_struct, ds):
411 case offsetof(struct user_regs_struct, es):
412 case offsetof(struct user_regs_struct, fs):
413 case offsetof(struct user_regs_struct, gs):
414 case offsetof(struct user_regs_struct, ss):
415 return get_segment_reg(task, offset);
416
417 case offsetof(struct user_regs_struct, flags):
418 return get_flags(task);
419
420#ifdef CONFIG_X86_64
421 case offsetof(struct user_regs_struct, fs_base):
422 return x86_fsbase_read_task(task);
423 case offsetof(struct user_regs_struct, gs_base):
424 return x86_gsbase_read_task(task);
425#endif
426 }
427
428 return *pt_regs_access(task_pt_regs(task), offset);
429}
430
431static int genregs_get(struct task_struct *target,
432 const struct user_regset *regset,
433 struct membuf to)
434{
435 int reg;
436
437 for (reg = 0; to.left; reg++)
438 membuf_store(&to, getreg(target, reg * sizeof(unsigned long)));
439 return 0;
440}
441
442static int genregs_set(struct task_struct *target,
443 const struct user_regset *regset,
444 unsigned int pos, unsigned int count,
445 const void *kbuf, const void __user *ubuf)
446{
447 int ret = 0;
448 if (kbuf) {
449 const unsigned long *k = kbuf;
450 while (count >= sizeof(*k) && !ret) {
451 ret = putreg(target, pos, *k++);
452 count -= sizeof(*k);
453 pos += sizeof(*k);
454 }
455 } else {
456 const unsigned long __user *u = ubuf;
457 while (count >= sizeof(*u) && !ret) {
458 unsigned long word;
459 ret = __get_user(word, u++);
460 if (ret)
461 break;
462 ret = putreg(target, pos, word);
463 count -= sizeof(*u);
464 pos += sizeof(*u);
465 }
466 }
467 return ret;
468}
469
470static void ptrace_triggered(struct perf_event *bp,
471 struct perf_sample_data *data,
472 struct pt_regs *regs)
473{
474 int i;
475 struct thread_struct *thread = &(current->thread);
476
477 /*
478 * Store in the virtual DR6 register the fact that the breakpoint
479 * was hit so the thread's debugger will see it.
480 */
481 for (i = 0; i < HBP_NUM; i++) {
482 if (thread->ptrace_bps[i] == bp)
483 break;
484 }
485
486 thread->virtual_dr6 |= (DR_TRAP0 << i);
487}
488
489/*
490 * Walk through every ptrace breakpoints for this thread and
491 * build the dr7 value on top of their attributes.
492 *
493 */
494static unsigned long ptrace_get_dr7(struct perf_event *bp[])
495{
496 int i;
497 int dr7 = 0;
498 struct arch_hw_breakpoint *info;
499
500 for (i = 0; i < HBP_NUM; i++) {
501 if (bp[i] && !bp[i]->attr.disabled) {
502 info = counter_arch_bp(bp[i]);
503 dr7 |= encode_dr7(i, info->len, info->type);
504 }
505 }
506
507 return dr7;
508}
509
510static int ptrace_fill_bp_fields(struct perf_event_attr *attr,
511 int len, int type, bool disabled)
512{
513 int err, bp_len, bp_type;
514
515 err = arch_bp_generic_fields(len, type, &bp_len, &bp_type);
516 if (!err) {
517 attr->bp_len = bp_len;
518 attr->bp_type = bp_type;
519 attr->disabled = disabled;
520 }
521
522 return err;
523}
524
525static struct perf_event *
526ptrace_register_breakpoint(struct task_struct *tsk, int len, int type,
527 unsigned long addr, bool disabled)
528{
529 struct perf_event_attr attr;
530 int err;
531
532 ptrace_breakpoint_init(&attr);
533 attr.bp_addr = addr;
534
535 err = ptrace_fill_bp_fields(&attr, len, type, disabled);
536 if (err)
537 return ERR_PTR(err);
538
539 return register_user_hw_breakpoint(&attr, ptrace_triggered,
540 NULL, tsk);
541}
542
543static int ptrace_modify_breakpoint(struct perf_event *bp, int len, int type,
544 int disabled)
545{
546 struct perf_event_attr attr = bp->attr;
547 int err;
548
549 err = ptrace_fill_bp_fields(&attr, len, type, disabled);
550 if (err)
551 return err;
552
553 return modify_user_hw_breakpoint(bp, &attr);
554}
555
556/*
557 * Handle ptrace writes to debug register 7.
558 */
559static int ptrace_write_dr7(struct task_struct *tsk, unsigned long data)
560{
561 struct thread_struct *thread = &tsk->thread;
562 unsigned long old_dr7;
563 bool second_pass = false;
564 int i, rc, ret = 0;
565
566 data &= ~DR_CONTROL_RESERVED;
567 old_dr7 = ptrace_get_dr7(thread->ptrace_bps);
568
569restore:
570 rc = 0;
571 for (i = 0; i < HBP_NUM; i++) {
572 unsigned len, type;
573 bool disabled = !decode_dr7(data, i, &len, &type);
574 struct perf_event *bp = thread->ptrace_bps[i];
575
576 if (!bp) {
577 if (disabled)
578 continue;
579
580 bp = ptrace_register_breakpoint(tsk,
581 len, type, 0, disabled);
582 if (IS_ERR(bp)) {
583 rc = PTR_ERR(bp);
584 break;
585 }
586
587 thread->ptrace_bps[i] = bp;
588 continue;
589 }
590
591 rc = ptrace_modify_breakpoint(bp, len, type, disabled);
592 if (rc)
593 break;
594 }
595
596 /* Restore if the first pass failed, second_pass shouldn't fail. */
597 if (rc && !WARN_ON(second_pass)) {
598 ret = rc;
599 data = old_dr7;
600 second_pass = true;
601 goto restore;
602 }
603
604 return ret;
605}
606
607/*
608 * Handle PTRACE_PEEKUSR calls for the debug register area.
609 */
610static unsigned long ptrace_get_debugreg(struct task_struct *tsk, int n)
611{
612 struct thread_struct *thread = &tsk->thread;
613 unsigned long val = 0;
614
615 if (n < HBP_NUM) {
616 int index = array_index_nospec(n, HBP_NUM);
617 struct perf_event *bp = thread->ptrace_bps[index];
618
619 if (bp)
620 val = bp->hw.info.address;
621 } else if (n == 6) {
622 val = thread->virtual_dr6 ^ DR6_RESERVED; /* Flip back to arch polarity */
623 } else if (n == 7) {
624 val = thread->ptrace_dr7;
625 }
626 return val;
627}
628
629static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr,
630 unsigned long addr)
631{
632 struct thread_struct *t = &tsk->thread;
633 struct perf_event *bp = t->ptrace_bps[nr];
634 int err = 0;
635
636 if (!bp) {
637 /*
638 * Put stub len and type to create an inactive but correct bp.
639 *
640 * CHECKME: the previous code returned -EIO if the addr wasn't
641 * a valid task virtual addr. The new one will return -EINVAL in
642 * this case.
643 * -EINVAL may be what we want for in-kernel breakpoints users,
644 * but -EIO looks better for ptrace, since we refuse a register
645 * writing for the user. And anyway this is the previous
646 * behaviour.
647 */
648 bp = ptrace_register_breakpoint(tsk,
649 X86_BREAKPOINT_LEN_1, X86_BREAKPOINT_WRITE,
650 addr, true);
651 if (IS_ERR(bp))
652 err = PTR_ERR(bp);
653 else
654 t->ptrace_bps[nr] = bp;
655 } else {
656 struct perf_event_attr attr = bp->attr;
657
658 attr.bp_addr = addr;
659 err = modify_user_hw_breakpoint(bp, &attr);
660 }
661
662 return err;
663}
664
665/*
666 * Handle PTRACE_POKEUSR calls for the debug register area.
667 */
668static int ptrace_set_debugreg(struct task_struct *tsk, int n,
669 unsigned long val)
670{
671 struct thread_struct *thread = &tsk->thread;
672 /* There are no DR4 or DR5 registers */
673 int rc = -EIO;
674
675 if (n < HBP_NUM) {
676 rc = ptrace_set_breakpoint_addr(tsk, n, val);
677 } else if (n == 6) {
678 thread->virtual_dr6 = val ^ DR6_RESERVED; /* Flip to positive polarity */
679 rc = 0;
680 } else if (n == 7) {
681 rc = ptrace_write_dr7(tsk, val);
682 if (!rc)
683 thread->ptrace_dr7 = val;
684 }
685 return rc;
686}
687
688/*
689 * These access the current or another (stopped) task's io permission
690 * bitmap for debugging or core dump.
691 */
692static int ioperm_active(struct task_struct *target,
693 const struct user_regset *regset)
694{
695 struct io_bitmap *iobm = target->thread.io_bitmap;
696
697 return iobm ? DIV_ROUND_UP(iobm->max, regset->size) : 0;
698}
699
700static int ioperm_get(struct task_struct *target,
701 const struct user_regset *regset,
702 struct membuf to)
703{
704 struct io_bitmap *iobm = target->thread.io_bitmap;
705
706 if (!iobm)
707 return -ENXIO;
708
709 return membuf_write(&to, iobm->bitmap, IO_BITMAP_BYTES);
710}
711
712/*
713 * Called by kernel/ptrace.c when detaching..
714 *
715 * Make sure the single step bit is not set.
716 */
717void ptrace_disable(struct task_struct *child)
718{
719 user_disable_single_step(child);
720}
721
722#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
723static const struct user_regset_view user_x86_32_view; /* Initialized below. */
724#endif
725#ifdef CONFIG_X86_64
726static const struct user_regset_view user_x86_64_view; /* Initialized below. */
727#endif
728
729long arch_ptrace(struct task_struct *child, long request,
730 unsigned long addr, unsigned long data)
731{
732 int ret;
733 unsigned long __user *datap = (unsigned long __user *)data;
734
735#ifdef CONFIG_X86_64
736 /* This is native 64-bit ptrace() */
737 const struct user_regset_view *regset_view = &user_x86_64_view;
738#else
739 /* This is native 32-bit ptrace() */
740 const struct user_regset_view *regset_view = &user_x86_32_view;
741#endif
742
743 switch (request) {
744 /* read the word at location addr in the USER area. */
745 case PTRACE_PEEKUSR: {
746 unsigned long tmp;
747
748 ret = -EIO;
749 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))
750 break;
751
752 tmp = 0; /* Default return condition */
753 if (addr < sizeof(struct user_regs_struct))
754 tmp = getreg(child, addr);
755 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
756 addr <= offsetof(struct user, u_debugreg[7])) {
757 addr -= offsetof(struct user, u_debugreg[0]);
758 tmp = ptrace_get_debugreg(child, addr / sizeof(data));
759 }
760 ret = put_user(tmp, datap);
761 break;
762 }
763
764 case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
765 ret = -EIO;
766 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))
767 break;
768
769 if (addr < sizeof(struct user_regs_struct))
770 ret = putreg(child, addr, data);
771 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
772 addr <= offsetof(struct user, u_debugreg[7])) {
773 addr -= offsetof(struct user, u_debugreg[0]);
774 ret = ptrace_set_debugreg(child,
775 addr / sizeof(data), data);
776 }
777 break;
778
779 case PTRACE_GETREGS: /* Get all gp regs from the child. */
780 return copy_regset_to_user(child,
781 regset_view,
782 REGSET_GENERAL,
783 0, sizeof(struct user_regs_struct),
784 datap);
785
786 case PTRACE_SETREGS: /* Set all gp regs in the child. */
787 return copy_regset_from_user(child,
788 regset_view,
789 REGSET_GENERAL,
790 0, sizeof(struct user_regs_struct),
791 datap);
792
793 case PTRACE_GETFPREGS: /* Get the child FPU state. */
794 return copy_regset_to_user(child,
795 regset_view,
796 REGSET_FP,
797 0, sizeof(struct user_i387_struct),
798 datap);
799
800 case PTRACE_SETFPREGS: /* Set the child FPU state. */
801 return copy_regset_from_user(child,
802 regset_view,
803 REGSET_FP,
804 0, sizeof(struct user_i387_struct),
805 datap);
806
807#ifdef CONFIG_X86_32
808 case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
809 return copy_regset_to_user(child, &user_x86_32_view,
810 REGSET32_XFP,
811 0, sizeof(struct user_fxsr_struct),
812 datap) ? -EIO : 0;
813
814 case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
815 return copy_regset_from_user(child, &user_x86_32_view,
816 REGSET32_XFP,
817 0, sizeof(struct user_fxsr_struct),
818 datap) ? -EIO : 0;
819#endif
820
821#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
822 case PTRACE_GET_THREAD_AREA:
823 if ((int) addr < 0)
824 return -EIO;
825 ret = do_get_thread_area(child, addr,
826 (struct user_desc __user *)data);
827 break;
828
829 case PTRACE_SET_THREAD_AREA:
830 if ((int) addr < 0)
831 return -EIO;
832 ret = do_set_thread_area(child, addr,
833 (struct user_desc __user *)data, 0);
834 break;
835#endif
836
837#ifdef CONFIG_X86_64
838 /* normal 64bit interface to access TLS data.
839 Works just like arch_prctl, except that the arguments
840 are reversed. */
841 case PTRACE_ARCH_PRCTL:
842 ret = do_arch_prctl_64(child, data, addr);
843 break;
844#endif
845
846 default:
847 ret = ptrace_request(child, request, addr, data);
848 break;
849 }
850
851 return ret;
852}
853
854#ifdef CONFIG_IA32_EMULATION
855
856#include <linux/compat.h>
857#include <linux/syscalls.h>
858#include <asm/ia32.h>
859#include <asm/user32.h>
860
861#define R32(l,q) \
862 case offsetof(struct user32, regs.l): \
863 regs->q = value; break
864
865#define SEG32(rs) \
866 case offsetof(struct user32, regs.rs): \
867 return set_segment_reg(child, \
868 offsetof(struct user_regs_struct, rs), \
869 value); \
870 break
871
872static int putreg32(struct task_struct *child, unsigned regno, u32 value)
873{
874 struct pt_regs *regs = task_pt_regs(child);
875 int ret;
876
877 switch (regno) {
878
879 SEG32(cs);
880 SEG32(ds);
881 SEG32(es);
882
883 /*
884 * A 32-bit ptracer on a 64-bit kernel expects that writing
885 * FS or GS will also update the base. This is needed for
886 * operations like PTRACE_SETREGS to fully restore a saved
887 * CPU state.
888 */
889
890 case offsetof(struct user32, regs.fs):
891 ret = set_segment_reg(child,
892 offsetof(struct user_regs_struct, fs),
893 value);
894 if (ret == 0)
895 child->thread.fsbase =
896 x86_fsgsbase_read_task(child, value);
897 return ret;
898
899 case offsetof(struct user32, regs.gs):
900 ret = set_segment_reg(child,
901 offsetof(struct user_regs_struct, gs),
902 value);
903 if (ret == 0)
904 child->thread.gsbase =
905 x86_fsgsbase_read_task(child, value);
906 return ret;
907
908 SEG32(ss);
909
910 R32(ebx, bx);
911 R32(ecx, cx);
912 R32(edx, dx);
913 R32(edi, di);
914 R32(esi, si);
915 R32(ebp, bp);
916 R32(eax, ax);
917 R32(eip, ip);
918 R32(esp, sp);
919
920 case offsetof(struct user32, regs.orig_eax):
921 /*
922 * Warning: bizarre corner case fixup here. A 32-bit
923 * debugger setting orig_eax to -1 wants to disable
924 * syscall restart. Make sure that the syscall
925 * restart code sign-extends orig_ax. Also make sure
926 * we interpret the -ERESTART* codes correctly if
927 * loaded into regs->ax in case the task is not
928 * actually still sitting at the exit from a 32-bit
929 * syscall with TS_COMPAT still set.
930 */
931 regs->orig_ax = value;
932 if (syscall_get_nr(child, regs) != -1)
933 child->thread_info.status |= TS_I386_REGS_POKED;
934 break;
935
936 case offsetof(struct user32, regs.eflags):
937 return set_flags(child, value);
938
939 case offsetof(struct user32, u_debugreg[0]) ...
940 offsetof(struct user32, u_debugreg[7]):
941 regno -= offsetof(struct user32, u_debugreg[0]);
942 return ptrace_set_debugreg(child, regno / 4, value);
943
944 default:
945 if (regno > sizeof(struct user32) || (regno & 3))
946 return -EIO;
947
948 /*
949 * Other dummy fields in the virtual user structure
950 * are ignored
951 */
952 break;
953 }
954 return 0;
955}
956
957#undef R32
958#undef SEG32
959
960#define R32(l,q) \
961 case offsetof(struct user32, regs.l): \
962 *val = regs->q; break
963
964#define SEG32(rs) \
965 case offsetof(struct user32, regs.rs): \
966 *val = get_segment_reg(child, \
967 offsetof(struct user_regs_struct, rs)); \
968 break
969
970static int getreg32(struct task_struct *child, unsigned regno, u32 *val)
971{
972 struct pt_regs *regs = task_pt_regs(child);
973
974 switch (regno) {
975
976 SEG32(ds);
977 SEG32(es);
978 SEG32(fs);
979 SEG32(gs);
980
981 R32(cs, cs);
982 R32(ss, ss);
983 R32(ebx, bx);
984 R32(ecx, cx);
985 R32(edx, dx);
986 R32(edi, di);
987 R32(esi, si);
988 R32(ebp, bp);
989 R32(eax, ax);
990 R32(orig_eax, orig_ax);
991 R32(eip, ip);
992 R32(esp, sp);
993
994 case offsetof(struct user32, regs.eflags):
995 *val = get_flags(child);
996 break;
997
998 case offsetof(struct user32, u_debugreg[0]) ...
999 offsetof(struct user32, u_debugreg[7]):
1000 regno -= offsetof(struct user32, u_debugreg[0]);
1001 *val = ptrace_get_debugreg(child, regno / 4);
1002 break;
1003
1004 default:
1005 if (regno > sizeof(struct user32) || (regno & 3))
1006 return -EIO;
1007
1008 /*
1009 * Other dummy fields in the virtual user structure
1010 * are ignored
1011 */
1012 *val = 0;
1013 break;
1014 }
1015 return 0;
1016}
1017
1018#undef R32
1019#undef SEG32
1020
1021static int genregs32_get(struct task_struct *target,
1022 const struct user_regset *regset,
1023 struct membuf to)
1024{
1025 int reg;
1026
1027 for (reg = 0; to.left; reg++) {
1028 u32 val;
1029 getreg32(target, reg * 4, &val);
1030 membuf_store(&to, val);
1031 }
1032 return 0;
1033}
1034
1035static int genregs32_set(struct task_struct *target,
1036 const struct user_regset *regset,
1037 unsigned int pos, unsigned int count,
1038 const void *kbuf, const void __user *ubuf)
1039{
1040 int ret = 0;
1041 if (kbuf) {
1042 const compat_ulong_t *k = kbuf;
1043 while (count >= sizeof(*k) && !ret) {
1044 ret = putreg32(target, pos, *k++);
1045 count -= sizeof(*k);
1046 pos += sizeof(*k);
1047 }
1048 } else {
1049 const compat_ulong_t __user *u = ubuf;
1050 while (count >= sizeof(*u) && !ret) {
1051 compat_ulong_t word;
1052 ret = __get_user(word, u++);
1053 if (ret)
1054 break;
1055 ret = putreg32(target, pos, word);
1056 count -= sizeof(*u);
1057 pos += sizeof(*u);
1058 }
1059 }
1060 return ret;
1061}
1062
1063static long ia32_arch_ptrace(struct task_struct *child, compat_long_t request,
1064 compat_ulong_t caddr, compat_ulong_t cdata)
1065{
1066 unsigned long addr = caddr;
1067 unsigned long data = cdata;
1068 void __user *datap = compat_ptr(data);
1069 int ret;
1070 __u32 val;
1071
1072 switch (request) {
1073 case PTRACE_PEEKUSR:
1074 ret = getreg32(child, addr, &val);
1075 if (ret == 0)
1076 ret = put_user(val, (__u32 __user *)datap);
1077 break;
1078
1079 case PTRACE_POKEUSR:
1080 ret = putreg32(child, addr, data);
1081 break;
1082
1083 case PTRACE_GETREGS: /* Get all gp regs from the child. */
1084 return copy_regset_to_user(child, &user_x86_32_view,
1085 REGSET_GENERAL,
1086 0, sizeof(struct user_regs_struct32),
1087 datap);
1088
1089 case PTRACE_SETREGS: /* Set all gp regs in the child. */
1090 return copy_regset_from_user(child, &user_x86_32_view,
1091 REGSET_GENERAL, 0,
1092 sizeof(struct user_regs_struct32),
1093 datap);
1094
1095 case PTRACE_GETFPREGS: /* Get the child FPU state. */
1096 return copy_regset_to_user(child, &user_x86_32_view,
1097 REGSET_FP, 0,
1098 sizeof(struct user_i387_ia32_struct),
1099 datap);
1100
1101 case PTRACE_SETFPREGS: /* Set the child FPU state. */
1102 return copy_regset_from_user(
1103 child, &user_x86_32_view, REGSET_FP,
1104 0, sizeof(struct user_i387_ia32_struct), datap);
1105
1106 case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
1107 return copy_regset_to_user(child, &user_x86_32_view,
1108 REGSET32_XFP, 0,
1109 sizeof(struct user32_fxsr_struct),
1110 datap);
1111
1112 case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
1113 return copy_regset_from_user(child, &user_x86_32_view,
1114 REGSET32_XFP, 0,
1115 sizeof(struct user32_fxsr_struct),
1116 datap);
1117
1118 case PTRACE_GET_THREAD_AREA:
1119 case PTRACE_SET_THREAD_AREA:
1120 return arch_ptrace(child, request, addr, data);
1121
1122 default:
1123 return compat_ptrace_request(child, request, addr, data);
1124 }
1125
1126 return ret;
1127}
1128#endif /* CONFIG_IA32_EMULATION */
1129
1130#ifdef CONFIG_X86_X32_ABI
1131static long x32_arch_ptrace(struct task_struct *child,
1132 compat_long_t request, compat_ulong_t caddr,
1133 compat_ulong_t cdata)
1134{
1135 unsigned long addr = caddr;
1136 unsigned long data = cdata;
1137 void __user *datap = compat_ptr(data);
1138 int ret;
1139
1140 switch (request) {
1141 /* Read 32bits at location addr in the USER area. Only allow
1142 to return the lower 32bits of segment and debug registers. */
1143 case PTRACE_PEEKUSR: {
1144 u32 tmp;
1145
1146 ret = -EIO;
1147 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user) ||
1148 addr < offsetof(struct user_regs_struct, cs))
1149 break;
1150
1151 tmp = 0; /* Default return condition */
1152 if (addr < sizeof(struct user_regs_struct))
1153 tmp = getreg(child, addr);
1154 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
1155 addr <= offsetof(struct user, u_debugreg[7])) {
1156 addr -= offsetof(struct user, u_debugreg[0]);
1157 tmp = ptrace_get_debugreg(child, addr / sizeof(data));
1158 }
1159 ret = put_user(tmp, (__u32 __user *)datap);
1160 break;
1161 }
1162
1163 /* Write the word at location addr in the USER area. Only allow
1164 to update segment and debug registers with the upper 32bits
1165 zero-extended. */
1166 case PTRACE_POKEUSR:
1167 ret = -EIO;
1168 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user) ||
1169 addr < offsetof(struct user_regs_struct, cs))
1170 break;
1171
1172 if (addr < sizeof(struct user_regs_struct))
1173 ret = putreg(child, addr, data);
1174 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
1175 addr <= offsetof(struct user, u_debugreg[7])) {
1176 addr -= offsetof(struct user, u_debugreg[0]);
1177 ret = ptrace_set_debugreg(child,
1178 addr / sizeof(data), data);
1179 }
1180 break;
1181
1182 case PTRACE_GETREGS: /* Get all gp regs from the child. */
1183 return copy_regset_to_user(child,
1184 &user_x86_64_view,
1185 REGSET_GENERAL,
1186 0, sizeof(struct user_regs_struct),
1187 datap);
1188
1189 case PTRACE_SETREGS: /* Set all gp regs in the child. */
1190 return copy_regset_from_user(child,
1191 &user_x86_64_view,
1192 REGSET_GENERAL,
1193 0, sizeof(struct user_regs_struct),
1194 datap);
1195
1196 case PTRACE_GETFPREGS: /* Get the child FPU state. */
1197 return copy_regset_to_user(child,
1198 &user_x86_64_view,
1199 REGSET_FP,
1200 0, sizeof(struct user_i387_struct),
1201 datap);
1202
1203 case PTRACE_SETFPREGS: /* Set the child FPU state. */
1204 return copy_regset_from_user(child,
1205 &user_x86_64_view,
1206 REGSET_FP,
1207 0, sizeof(struct user_i387_struct),
1208 datap);
1209
1210 default:
1211 return compat_ptrace_request(child, request, addr, data);
1212 }
1213
1214 return ret;
1215}
1216#endif
1217
1218#ifdef CONFIG_COMPAT
1219long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
1220 compat_ulong_t caddr, compat_ulong_t cdata)
1221{
1222#ifdef CONFIG_X86_X32_ABI
1223 if (!in_ia32_syscall())
1224 return x32_arch_ptrace(child, request, caddr, cdata);
1225#endif
1226#ifdef CONFIG_IA32_EMULATION
1227 return ia32_arch_ptrace(child, request, caddr, cdata);
1228#else
1229 return 0;
1230#endif
1231}
1232#endif /* CONFIG_COMPAT */
1233
1234#ifdef CONFIG_X86_64
1235
1236static struct user_regset x86_64_regsets[] __ro_after_init = {
1237 [REGSET64_GENERAL] = {
1238 .core_note_type = NT_PRSTATUS,
1239 .n = sizeof(struct user_regs_struct) / sizeof(long),
1240 .size = sizeof(long),
1241 .align = sizeof(long),
1242 .regset_get = genregs_get,
1243 .set = genregs_set
1244 },
1245 [REGSET64_FP] = {
1246 .core_note_type = NT_PRFPREG,
1247 .n = sizeof(struct fxregs_state) / sizeof(long),
1248 .size = sizeof(long),
1249 .align = sizeof(long),
1250 .active = regset_xregset_fpregs_active,
1251 .regset_get = xfpregs_get,
1252 .set = xfpregs_set
1253 },
1254 [REGSET64_XSTATE] = {
1255 .core_note_type = NT_X86_XSTATE,
1256 .size = sizeof(u64),
1257 .align = sizeof(u64),
1258 .active = xstateregs_active,
1259 .regset_get = xstateregs_get,
1260 .set = xstateregs_set
1261 },
1262 [REGSET64_IOPERM] = {
1263 .core_note_type = NT_386_IOPERM,
1264 .n = IO_BITMAP_LONGS,
1265 .size = sizeof(long),
1266 .align = sizeof(long),
1267 .active = ioperm_active,
1268 .regset_get = ioperm_get
1269 },
1270};
1271
1272static const struct user_regset_view user_x86_64_view = {
1273 .name = "x86_64", .e_machine = EM_X86_64,
1274 .regsets = x86_64_regsets, .n = ARRAY_SIZE(x86_64_regsets)
1275};
1276
1277#else /* CONFIG_X86_32 */
1278
1279#define user_regs_struct32 user_regs_struct
1280#define genregs32_get genregs_get
1281#define genregs32_set genregs_set
1282
1283#endif /* CONFIG_X86_64 */
1284
1285#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1286static struct user_regset x86_32_regsets[] __ro_after_init = {
1287 [REGSET32_GENERAL] = {
1288 .core_note_type = NT_PRSTATUS,
1289 .n = sizeof(struct user_regs_struct32) / sizeof(u32),
1290 .size = sizeof(u32),
1291 .align = sizeof(u32),
1292 .regset_get = genregs32_get,
1293 .set = genregs32_set
1294 },
1295 [REGSET32_FP] = {
1296 .core_note_type = NT_PRFPREG,
1297 .n = sizeof(struct user_i387_ia32_struct) / sizeof(u32),
1298 .size = sizeof(u32),
1299 .align = sizeof(u32),
1300 .active = regset_fpregs_active,
1301 .regset_get = fpregs_get,
1302 .set = fpregs_set
1303 },
1304 [REGSET32_XFP] = {
1305 .core_note_type = NT_PRXFPREG,
1306 .n = sizeof(struct fxregs_state) / sizeof(u32),
1307 .size = sizeof(u32),
1308 .align = sizeof(u32),
1309 .active = regset_xregset_fpregs_active,
1310 .regset_get = xfpregs_get,
1311 .set = xfpregs_set
1312 },
1313 [REGSET32_XSTATE] = {
1314 .core_note_type = NT_X86_XSTATE,
1315 .size = sizeof(u64),
1316 .align = sizeof(u64),
1317 .active = xstateregs_active,
1318 .regset_get = xstateregs_get,
1319 .set = xstateregs_set
1320 },
1321 [REGSET32_TLS] = {
1322 .core_note_type = NT_386_TLS,
1323 .n = GDT_ENTRY_TLS_ENTRIES,
1324 .bias = GDT_ENTRY_TLS_MIN,
1325 .size = sizeof(struct user_desc),
1326 .align = sizeof(struct user_desc),
1327 .active = regset_tls_active,
1328 .regset_get = regset_tls_get,
1329 .set = regset_tls_set
1330 },
1331 [REGSET32_IOPERM] = {
1332 .core_note_type = NT_386_IOPERM,
1333 .n = IO_BITMAP_BYTES / sizeof(u32),
1334 .size = sizeof(u32),
1335 .align = sizeof(u32),
1336 .active = ioperm_active,
1337 .regset_get = ioperm_get
1338 },
1339};
1340
1341static const struct user_regset_view user_x86_32_view = {
1342 .name = "i386", .e_machine = EM_386,
1343 .regsets = x86_32_regsets, .n = ARRAY_SIZE(x86_32_regsets)
1344};
1345#endif
1346
1347/*
1348 * This represents bytes 464..511 in the memory layout exported through
1349 * the REGSET_XSTATE interface.
1350 */
1351u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
1352
1353void __init update_regset_xstate_info(unsigned int size, u64 xstate_mask)
1354{
1355#ifdef CONFIG_X86_64
1356 x86_64_regsets[REGSET64_XSTATE].n = size / sizeof(u64);
1357#endif
1358#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1359 x86_32_regsets[REGSET32_XSTATE].n = size / sizeof(u64);
1360#endif
1361 xstate_fx_sw_bytes[USER_XSTATE_XCR0_WORD] = xstate_mask;
1362}
1363
1364/*
1365 * This is used by the core dump code to decide which regset to dump. The
1366 * core dump code writes out the resulting .e_machine and the corresponding
1367 * regsets. This is suboptimal if the task is messing around with its CS.L
1368 * field, but at worst the core dump will end up missing some information.
1369 *
1370 * Unfortunately, it is also used by the broken PTRACE_GETREGSET and
1371 * PTRACE_SETREGSET APIs. These APIs look at the .regsets field but have
1372 * no way to make sure that the e_machine they use matches the caller's
1373 * expectations. The result is that the data format returned by
1374 * PTRACE_GETREGSET depends on the returned CS field (and even the offset
1375 * of the returned CS field depends on its value!) and the data format
1376 * accepted by PTRACE_SETREGSET is determined by the old CS value. The
1377 * upshot is that it is basically impossible to use these APIs correctly.
1378 *
1379 * The best way to fix it in the long run would probably be to add new
1380 * improved ptrace() APIs to read and write registers reliably, possibly by
1381 * allowing userspace to select the ELF e_machine variant that they expect.
1382 */
1383const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1384{
1385#ifdef CONFIG_IA32_EMULATION
1386 if (!user_64bit_mode(task_pt_regs(task)))
1387#endif
1388#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1389 return &user_x86_32_view;
1390#endif
1391#ifdef CONFIG_X86_64
1392 return &user_x86_64_view;
1393#endif
1394}
1395
1396void send_sigtrap(struct pt_regs *regs, int error_code, int si_code)
1397{
1398 struct task_struct *tsk = current;
1399
1400 tsk->thread.trap_nr = X86_TRAP_DB;
1401 tsk->thread.error_code = error_code;
1402
1403 /* Send us the fake SIGTRAP */
1404 force_sig_fault(SIGTRAP, si_code,
1405 user_mode(regs) ? (void __user *)regs->ip : NULL);
1406}
1407
1408void user_single_step_report(struct pt_regs *regs)
1409{
1410 send_sigtrap(regs, 0, TRAP_BRKPT);
1411}