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