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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/* 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/mm.h>
10#include <linux/smp.h>
11#include <linux/errno.h>
12#include <linux/slab.h>
13#include <linux/ptrace.h>
14#include <linux/regset.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
25#include <asm/uaccess.h>
26#include <asm/pgtable.h>
27#include <asm/system.h>
28#include <asm/processor.h>
29#include <asm/i387.h>
30#include <asm/debugreg.h>
31#include <asm/ldt.h>
32#include <asm/desc.h>
33#include <asm/prctl.h>
34#include <asm/proto.h>
35#include <asm/hw_breakpoint.h>
36
37#include "tls.h"
38
39#define CREATE_TRACE_POINTS
40#include <trace/events/syscalls.h>
41
42enum x86_regset {
43 REGSET_GENERAL,
44 REGSET_FP,
45 REGSET_XFP,
46 REGSET_IOPERM64 = REGSET_XFP,
47 REGSET_XSTATE,
48 REGSET_TLS,
49 REGSET_IOPERM32,
50};
51
52struct pt_regs_offset {
53 const char *name;
54 int offset;
55};
56
57#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
58#define REG_OFFSET_END {.name = NULL, .offset = 0}
59
60static const struct pt_regs_offset regoffset_table[] = {
61#ifdef CONFIG_X86_64
62 REG_OFFSET_NAME(r15),
63 REG_OFFSET_NAME(r14),
64 REG_OFFSET_NAME(r13),
65 REG_OFFSET_NAME(r12),
66 REG_OFFSET_NAME(r11),
67 REG_OFFSET_NAME(r10),
68 REG_OFFSET_NAME(r9),
69 REG_OFFSET_NAME(r8),
70#endif
71 REG_OFFSET_NAME(bx),
72 REG_OFFSET_NAME(cx),
73 REG_OFFSET_NAME(dx),
74 REG_OFFSET_NAME(si),
75 REG_OFFSET_NAME(di),
76 REG_OFFSET_NAME(bp),
77 REG_OFFSET_NAME(ax),
78#ifdef CONFIG_X86_32
79 REG_OFFSET_NAME(ds),
80 REG_OFFSET_NAME(es),
81 REG_OFFSET_NAME(fs),
82 REG_OFFSET_NAME(gs),
83#endif
84 REG_OFFSET_NAME(orig_ax),
85 REG_OFFSET_NAME(ip),
86 REG_OFFSET_NAME(cs),
87 REG_OFFSET_NAME(flags),
88 REG_OFFSET_NAME(sp),
89 REG_OFFSET_NAME(ss),
90 REG_OFFSET_END,
91};
92
93/**
94 * regs_query_register_offset() - query register offset from its name
95 * @name: the name of a register
96 *
97 * regs_query_register_offset() returns the offset of a register in struct
98 * pt_regs from its name. If the name is invalid, this returns -EINVAL;
99 */
100int regs_query_register_offset(const char *name)
101{
102 const struct pt_regs_offset *roff;
103 for (roff = regoffset_table; roff->name != NULL; roff++)
104 if (!strcmp(roff->name, name))
105 return roff->offset;
106 return -EINVAL;
107}
108
109/**
110 * regs_query_register_name() - query register name from its offset
111 * @offset: the offset of a register in struct pt_regs.
112 *
113 * regs_query_register_name() returns the name of a register from its
114 * offset in struct pt_regs. If the @offset is invalid, this returns NULL;
115 */
116const char *regs_query_register_name(unsigned int offset)
117{
118 const struct pt_regs_offset *roff;
119 for (roff = regoffset_table; roff->name != NULL; roff++)
120 if (roff->offset == offset)
121 return roff->name;
122 return NULL;
123}
124
125static const int arg_offs_table[] = {
126#ifdef CONFIG_X86_32
127 [0] = offsetof(struct pt_regs, ax),
128 [1] = offsetof(struct pt_regs, dx),
129 [2] = offsetof(struct pt_regs, cx)
130#else /* CONFIG_X86_64 */
131 [0] = offsetof(struct pt_regs, di),
132 [1] = offsetof(struct pt_regs, si),
133 [2] = offsetof(struct pt_regs, dx),
134 [3] = offsetof(struct pt_regs, cx),
135 [4] = offsetof(struct pt_regs, r8),
136 [5] = offsetof(struct pt_regs, r9)
137#endif
138};
139
140/*
141 * does not yet catch signals sent when the child dies.
142 * in exit.c or in signal.c.
143 */
144
145/*
146 * Determines which flags the user has access to [1 = access, 0 = no access].
147 */
148#define FLAG_MASK_32 ((unsigned long) \
149 (X86_EFLAGS_CF | X86_EFLAGS_PF | \
150 X86_EFLAGS_AF | X86_EFLAGS_ZF | \
151 X86_EFLAGS_SF | X86_EFLAGS_TF | \
152 X86_EFLAGS_DF | X86_EFLAGS_OF | \
153 X86_EFLAGS_RF | X86_EFLAGS_AC))
154
155/*
156 * Determines whether a value may be installed in a segment register.
157 */
158static inline bool invalid_selector(u16 value)
159{
160 return unlikely(value != 0 && (value & SEGMENT_RPL_MASK) != USER_RPL);
161}
162
163#ifdef CONFIG_X86_32
164
165#define FLAG_MASK FLAG_MASK_32
166
167static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long regno)
168{
169 BUILD_BUG_ON(offsetof(struct pt_regs, bx) != 0);
170 return ®s->bx + (regno >> 2);
171}
172
173static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
174{
175 /*
176 * Returning the value truncates it to 16 bits.
177 */
178 unsigned int retval;
179 if (offset != offsetof(struct user_regs_struct, gs))
180 retval = *pt_regs_access(task_pt_regs(task), offset);
181 else {
182 if (task == current)
183 retval = get_user_gs(task_pt_regs(task));
184 else
185 retval = task_user_gs(task);
186 }
187 return retval;
188}
189
190static int set_segment_reg(struct task_struct *task,
191 unsigned long offset, u16 value)
192{
193 /*
194 * The value argument was already truncated to 16 bits.
195 */
196 if (invalid_selector(value))
197 return -EIO;
198
199 /*
200 * For %cs and %ss we cannot permit a null selector.
201 * We can permit a bogus selector as long as it has USER_RPL.
202 * Null selectors are fine for other segment registers, but
203 * we will never get back to user mode with invalid %cs or %ss
204 * and will take the trap in iret instead. Much code relies
205 * on user_mode() to distinguish a user trap frame (which can
206 * safely use invalid selectors) from a kernel trap frame.
207 */
208 switch (offset) {
209 case offsetof(struct user_regs_struct, cs):
210 case offsetof(struct user_regs_struct, ss):
211 if (unlikely(value == 0))
212 return -EIO;
213
214 default:
215 *pt_regs_access(task_pt_regs(task), offset) = value;
216 break;
217
218 case offsetof(struct user_regs_struct, gs):
219 if (task == current)
220 set_user_gs(task_pt_regs(task), value);
221 else
222 task_user_gs(task) = value;
223 }
224
225 return 0;
226}
227
228#else /* CONFIG_X86_64 */
229
230#define FLAG_MASK (FLAG_MASK_32 | X86_EFLAGS_NT)
231
232static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long offset)
233{
234 BUILD_BUG_ON(offsetof(struct pt_regs, r15) != 0);
235 return ®s->r15 + (offset / sizeof(regs->r15));
236}
237
238static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
239{
240 /*
241 * Returning the value truncates it to 16 bits.
242 */
243 unsigned int seg;
244
245 switch (offset) {
246 case offsetof(struct user_regs_struct, fs):
247 if (task == current) {
248 /* Older gas can't assemble movq %?s,%r?? */
249 asm("movl %%fs,%0" : "=r" (seg));
250 return seg;
251 }
252 return task->thread.fsindex;
253 case offsetof(struct user_regs_struct, gs):
254 if (task == current) {
255 asm("movl %%gs,%0" : "=r" (seg));
256 return seg;
257 }
258 return task->thread.gsindex;
259 case offsetof(struct user_regs_struct, ds):
260 if (task == current) {
261 asm("movl %%ds,%0" : "=r" (seg));
262 return seg;
263 }
264 return task->thread.ds;
265 case offsetof(struct user_regs_struct, es):
266 if (task == current) {
267 asm("movl %%es,%0" : "=r" (seg));
268 return seg;
269 }
270 return task->thread.es;
271
272 case offsetof(struct user_regs_struct, cs):
273 case offsetof(struct user_regs_struct, ss):
274 break;
275 }
276 return *pt_regs_access(task_pt_regs(task), offset);
277}
278
279static int set_segment_reg(struct task_struct *task,
280 unsigned long offset, u16 value)
281{
282 /*
283 * The value argument was already truncated to 16 bits.
284 */
285 if (invalid_selector(value))
286 return -EIO;
287
288 switch (offset) {
289 case offsetof(struct user_regs_struct,fs):
290 /*
291 * If this is setting fs as for normal 64-bit use but
292 * setting fs_base has implicitly changed it, leave it.
293 */
294 if ((value == FS_TLS_SEL && task->thread.fsindex == 0 &&
295 task->thread.fs != 0) ||
296 (value == 0 && task->thread.fsindex == FS_TLS_SEL &&
297 task->thread.fs == 0))
298 break;
299 task->thread.fsindex = value;
300 if (task == current)
301 loadsegment(fs, task->thread.fsindex);
302 break;
303 case offsetof(struct user_regs_struct,gs):
304 /*
305 * If this is setting gs as for normal 64-bit use but
306 * setting gs_base has implicitly changed it, leave it.
307 */
308 if ((value == GS_TLS_SEL && task->thread.gsindex == 0 &&
309 task->thread.gs != 0) ||
310 (value == 0 && task->thread.gsindex == GS_TLS_SEL &&
311 task->thread.gs == 0))
312 break;
313 task->thread.gsindex = value;
314 if (task == current)
315 load_gs_index(task->thread.gsindex);
316 break;
317 case offsetof(struct user_regs_struct,ds):
318 task->thread.ds = value;
319 if (task == current)
320 loadsegment(ds, task->thread.ds);
321 break;
322 case offsetof(struct user_regs_struct,es):
323 task->thread.es = value;
324 if (task == current)
325 loadsegment(es, task->thread.es);
326 break;
327
328 /*
329 * Can't actually change these in 64-bit mode.
330 */
331 case offsetof(struct user_regs_struct,cs):
332 if (unlikely(value == 0))
333 return -EIO;
334#ifdef CONFIG_IA32_EMULATION
335 if (test_tsk_thread_flag(task, TIF_IA32))
336 task_pt_regs(task)->cs = value;
337#endif
338 break;
339 case offsetof(struct user_regs_struct,ss):
340 if (unlikely(value == 0))
341 return -EIO;
342#ifdef CONFIG_IA32_EMULATION
343 if (test_tsk_thread_flag(task, TIF_IA32))
344 task_pt_regs(task)->ss = value;
345#endif
346 break;
347 }
348
349 return 0;
350}
351
352#endif /* CONFIG_X86_32 */
353
354static unsigned long get_flags(struct task_struct *task)
355{
356 unsigned long retval = task_pt_regs(task)->flags;
357
358 /*
359 * If the debugger set TF, hide it from the readout.
360 */
361 if (test_tsk_thread_flag(task, TIF_FORCED_TF))
362 retval &= ~X86_EFLAGS_TF;
363
364 return retval;
365}
366
367static int set_flags(struct task_struct *task, unsigned long value)
368{
369 struct pt_regs *regs = task_pt_regs(task);
370
371 /*
372 * If the user value contains TF, mark that
373 * it was not "us" (the debugger) that set it.
374 * If not, make sure it stays set if we had.
375 */
376 if (value & X86_EFLAGS_TF)
377 clear_tsk_thread_flag(task, TIF_FORCED_TF);
378 else if (test_tsk_thread_flag(task, TIF_FORCED_TF))
379 value |= X86_EFLAGS_TF;
380
381 regs->flags = (regs->flags & ~FLAG_MASK) | (value & FLAG_MASK);
382
383 return 0;
384}
385
386static int putreg(struct task_struct *child,
387 unsigned long offset, unsigned long value)
388{
389 switch (offset) {
390 case offsetof(struct user_regs_struct, cs):
391 case offsetof(struct user_regs_struct, ds):
392 case offsetof(struct user_regs_struct, es):
393 case offsetof(struct user_regs_struct, fs):
394 case offsetof(struct user_regs_struct, gs):
395 case offsetof(struct user_regs_struct, ss):
396 return set_segment_reg(child, offset, value);
397
398 case offsetof(struct user_regs_struct, flags):
399 return set_flags(child, value);
400
401#ifdef CONFIG_X86_64
402 case offsetof(struct user_regs_struct,fs_base):
403 if (value >= TASK_SIZE_OF(child))
404 return -EIO;
405 /*
406 * When changing the segment base, use do_arch_prctl
407 * to set either thread.fs or thread.fsindex and the
408 * corresponding GDT slot.
409 */
410 if (child->thread.fs != value)
411 return do_arch_prctl(child, ARCH_SET_FS, value);
412 return 0;
413 case offsetof(struct user_regs_struct,gs_base):
414 /*
415 * Exactly the same here as the %fs handling above.
416 */
417 if (value >= TASK_SIZE_OF(child))
418 return -EIO;
419 if (child->thread.gs != value)
420 return do_arch_prctl(child, ARCH_SET_GS, value);
421 return 0;
422#endif
423 }
424
425 *pt_regs_access(task_pt_regs(child), offset) = value;
426 return 0;
427}
428
429static unsigned long getreg(struct task_struct *task, unsigned long offset)
430{
431 switch (offset) {
432 case offsetof(struct user_regs_struct, cs):
433 case offsetof(struct user_regs_struct, ds):
434 case offsetof(struct user_regs_struct, es):
435 case offsetof(struct user_regs_struct, fs):
436 case offsetof(struct user_regs_struct, gs):
437 case offsetof(struct user_regs_struct, ss):
438 return get_segment_reg(task, offset);
439
440 case offsetof(struct user_regs_struct, flags):
441 return get_flags(task);
442
443#ifdef CONFIG_X86_64
444 case offsetof(struct user_regs_struct, fs_base): {
445 /*
446 * do_arch_prctl may have used a GDT slot instead of
447 * the MSR. To userland, it appears the same either
448 * way, except the %fs segment selector might not be 0.
449 */
450 unsigned int seg = task->thread.fsindex;
451 if (task->thread.fs != 0)
452 return task->thread.fs;
453 if (task == current)
454 asm("movl %%fs,%0" : "=r" (seg));
455 if (seg != FS_TLS_SEL)
456 return 0;
457 return get_desc_base(&task->thread.tls_array[FS_TLS]);
458 }
459 case offsetof(struct user_regs_struct, gs_base): {
460 /*
461 * Exactly the same here as the %fs handling above.
462 */
463 unsigned int seg = task->thread.gsindex;
464 if (task->thread.gs != 0)
465 return task->thread.gs;
466 if (task == current)
467 asm("movl %%gs,%0" : "=r" (seg));
468 if (seg != GS_TLS_SEL)
469 return 0;
470 return get_desc_base(&task->thread.tls_array[GS_TLS]);
471 }
472#endif
473 }
474
475 return *pt_regs_access(task_pt_regs(task), offset);
476}
477
478static int genregs_get(struct task_struct *target,
479 const struct user_regset *regset,
480 unsigned int pos, unsigned int count,
481 void *kbuf, void __user *ubuf)
482{
483 if (kbuf) {
484 unsigned long *k = kbuf;
485 while (count >= sizeof(*k)) {
486 *k++ = getreg(target, pos);
487 count -= sizeof(*k);
488 pos += sizeof(*k);
489 }
490 } else {
491 unsigned long __user *u = ubuf;
492 while (count >= sizeof(*u)) {
493 if (__put_user(getreg(target, pos), u++))
494 return -EFAULT;
495 count -= sizeof(*u);
496 pos += sizeof(*u);
497 }
498 }
499
500 return 0;
501}
502
503static int genregs_set(struct task_struct *target,
504 const struct user_regset *regset,
505 unsigned int pos, unsigned int count,
506 const void *kbuf, const void __user *ubuf)
507{
508 int ret = 0;
509 if (kbuf) {
510 const unsigned long *k = kbuf;
511 while (count >= sizeof(*k) && !ret) {
512 ret = putreg(target, pos, *k++);
513 count -= sizeof(*k);
514 pos += sizeof(*k);
515 }
516 } else {
517 const unsigned long __user *u = ubuf;
518 while (count >= sizeof(*u) && !ret) {
519 unsigned long word;
520 ret = __get_user(word, u++);
521 if (ret)
522 break;
523 ret = putreg(target, pos, word);
524 count -= sizeof(*u);
525 pos += sizeof(*u);
526 }
527 }
528 return ret;
529}
530
531static void ptrace_triggered(struct perf_event *bp,
532 struct perf_sample_data *data,
533 struct pt_regs *regs)
534{
535 int i;
536 struct thread_struct *thread = &(current->thread);
537
538 /*
539 * Store in the virtual DR6 register the fact that the breakpoint
540 * was hit so the thread's debugger will see it.
541 */
542 for (i = 0; i < HBP_NUM; i++) {
543 if (thread->ptrace_bps[i] == bp)
544 break;
545 }
546
547 thread->debugreg6 |= (DR_TRAP0 << i);
548}
549
550/*
551 * Walk through every ptrace breakpoints for this thread and
552 * build the dr7 value on top of their attributes.
553 *
554 */
555static unsigned long ptrace_get_dr7(struct perf_event *bp[])
556{
557 int i;
558 int dr7 = 0;
559 struct arch_hw_breakpoint *info;
560
561 for (i = 0; i < HBP_NUM; i++) {
562 if (bp[i] && !bp[i]->attr.disabled) {
563 info = counter_arch_bp(bp[i]);
564 dr7 |= encode_dr7(i, info->len, info->type);
565 }
566 }
567
568 return dr7;
569}
570
571static int
572ptrace_modify_breakpoint(struct perf_event *bp, int len, int type,
573 struct task_struct *tsk, int disabled)
574{
575 int err;
576 int gen_len, gen_type;
577 struct perf_event_attr attr;
578
579 /*
580 * We should have at least an inactive breakpoint at this
581 * slot. It means the user is writing dr7 without having
582 * written the address register first
583 */
584 if (!bp)
585 return -EINVAL;
586
587 err = arch_bp_generic_fields(len, type, &gen_len, &gen_type);
588 if (err)
589 return err;
590
591 attr = bp->attr;
592 attr.bp_len = gen_len;
593 attr.bp_type = gen_type;
594 attr.disabled = disabled;
595
596 return modify_user_hw_breakpoint(bp, &attr);
597}
598
599/*
600 * Handle ptrace writes to debug register 7.
601 */
602static int ptrace_write_dr7(struct task_struct *tsk, unsigned long data)
603{
604 struct thread_struct *thread = &(tsk->thread);
605 unsigned long old_dr7;
606 int i, orig_ret = 0, rc = 0;
607 int enabled, second_pass = 0;
608 unsigned len, type;
609 struct perf_event *bp;
610
611 if (ptrace_get_breakpoints(tsk) < 0)
612 return -ESRCH;
613
614 data &= ~DR_CONTROL_RESERVED;
615 old_dr7 = ptrace_get_dr7(thread->ptrace_bps);
616restore:
617 /*
618 * Loop through all the hardware breakpoints, making the
619 * appropriate changes to each.
620 */
621 for (i = 0; i < HBP_NUM; i++) {
622 enabled = decode_dr7(data, i, &len, &type);
623 bp = thread->ptrace_bps[i];
624
625 if (!enabled) {
626 if (bp) {
627 /*
628 * Don't unregister the breakpoints right-away,
629 * unless all register_user_hw_breakpoint()
630 * requests have succeeded. This prevents
631 * any window of opportunity for debug
632 * register grabbing by other users.
633 */
634 if (!second_pass)
635 continue;
636
637 rc = ptrace_modify_breakpoint(bp, len, type,
638 tsk, 1);
639 if (rc)
640 break;
641 }
642 continue;
643 }
644
645 rc = ptrace_modify_breakpoint(bp, len, type, tsk, 0);
646 if (rc)
647 break;
648 }
649 /*
650 * Make a second pass to free the remaining unused breakpoints
651 * or to restore the original breakpoints if an error occurred.
652 */
653 if (!second_pass) {
654 second_pass = 1;
655 if (rc < 0) {
656 orig_ret = rc;
657 data = old_dr7;
658 }
659 goto restore;
660 }
661
662 ptrace_put_breakpoints(tsk);
663
664 return ((orig_ret < 0) ? orig_ret : rc);
665}
666
667/*
668 * Handle PTRACE_PEEKUSR calls for the debug register area.
669 */
670static unsigned long ptrace_get_debugreg(struct task_struct *tsk, int n)
671{
672 struct thread_struct *thread = &(tsk->thread);
673 unsigned long val = 0;
674
675 if (n < HBP_NUM) {
676 struct perf_event *bp;
677
678 if (ptrace_get_breakpoints(tsk) < 0)
679 return -ESRCH;
680
681 bp = thread->ptrace_bps[n];
682 if (!bp)
683 val = 0;
684 else
685 val = bp->hw.info.address;
686
687 ptrace_put_breakpoints(tsk);
688 } else if (n == 6) {
689 val = thread->debugreg6;
690 } else if (n == 7) {
691 val = thread->ptrace_dr7;
692 }
693 return val;
694}
695
696static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr,
697 unsigned long addr)
698{
699 struct perf_event *bp;
700 struct thread_struct *t = &tsk->thread;
701 struct perf_event_attr attr;
702 int err = 0;
703
704 if (ptrace_get_breakpoints(tsk) < 0)
705 return -ESRCH;
706
707 if (!t->ptrace_bps[nr]) {
708 ptrace_breakpoint_init(&attr);
709 /*
710 * Put stub len and type to register (reserve) an inactive but
711 * correct bp
712 */
713 attr.bp_addr = addr;
714 attr.bp_len = HW_BREAKPOINT_LEN_1;
715 attr.bp_type = HW_BREAKPOINT_W;
716 attr.disabled = 1;
717
718 bp = register_user_hw_breakpoint(&attr, ptrace_triggered,
719 NULL, tsk);
720
721 /*
722 * CHECKME: the previous code returned -EIO if the addr wasn't
723 * a valid task virtual addr. The new one will return -EINVAL in
724 * this case.
725 * -EINVAL may be what we want for in-kernel breakpoints users,
726 * but -EIO looks better for ptrace, since we refuse a register
727 * writing for the user. And anyway this is the previous
728 * behaviour.
729 */
730 if (IS_ERR(bp)) {
731 err = PTR_ERR(bp);
732 goto put;
733 }
734
735 t->ptrace_bps[nr] = bp;
736 } else {
737 bp = t->ptrace_bps[nr];
738
739 attr = bp->attr;
740 attr.bp_addr = addr;
741 err = modify_user_hw_breakpoint(bp, &attr);
742 }
743
744put:
745 ptrace_put_breakpoints(tsk);
746 return err;
747}
748
749/*
750 * Handle PTRACE_POKEUSR calls for the debug register area.
751 */
752int ptrace_set_debugreg(struct task_struct *tsk, int n, unsigned long val)
753{
754 struct thread_struct *thread = &(tsk->thread);
755 int rc = 0;
756
757 /* There are no DR4 or DR5 registers */
758 if (n == 4 || n == 5)
759 return -EIO;
760
761 if (n == 6) {
762 thread->debugreg6 = val;
763 goto ret_path;
764 }
765 if (n < HBP_NUM) {
766 rc = ptrace_set_breakpoint_addr(tsk, n, val);
767 if (rc)
768 return rc;
769 }
770 /* All that's left is DR7 */
771 if (n == 7) {
772 rc = ptrace_write_dr7(tsk, val);
773 if (!rc)
774 thread->ptrace_dr7 = val;
775 }
776
777ret_path:
778 return rc;
779}
780
781/*
782 * These access the current or another (stopped) task's io permission
783 * bitmap for debugging or core dump.
784 */
785static int ioperm_active(struct task_struct *target,
786 const struct user_regset *regset)
787{
788 return target->thread.io_bitmap_max / regset->size;
789}
790
791static int ioperm_get(struct task_struct *target,
792 const struct user_regset *regset,
793 unsigned int pos, unsigned int count,
794 void *kbuf, void __user *ubuf)
795{
796 if (!target->thread.io_bitmap_ptr)
797 return -ENXIO;
798
799 return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
800 target->thread.io_bitmap_ptr,
801 0, IO_BITMAP_BYTES);
802}
803
804/*
805 * Called by kernel/ptrace.c when detaching..
806 *
807 * Make sure the single step bit is not set.
808 */
809void ptrace_disable(struct task_struct *child)
810{
811 user_disable_single_step(child);
812#ifdef TIF_SYSCALL_EMU
813 clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
814#endif
815}
816
817#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
818static const struct user_regset_view user_x86_32_view; /* Initialized below. */
819#endif
820
821long arch_ptrace(struct task_struct *child, long request,
822 unsigned long addr, unsigned long data)
823{
824 int ret;
825 unsigned long __user *datap = (unsigned long __user *)data;
826
827 switch (request) {
828 /* read the word at location addr in the USER area. */
829 case PTRACE_PEEKUSR: {
830 unsigned long tmp;
831
832 ret = -EIO;
833 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))
834 break;
835
836 tmp = 0; /* Default return condition */
837 if (addr < sizeof(struct user_regs_struct))
838 tmp = getreg(child, addr);
839 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
840 addr <= offsetof(struct user, u_debugreg[7])) {
841 addr -= offsetof(struct user, u_debugreg[0]);
842 tmp = ptrace_get_debugreg(child, addr / sizeof(data));
843 }
844 ret = put_user(tmp, datap);
845 break;
846 }
847
848 case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
849 ret = -EIO;
850 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))
851 break;
852
853 if (addr < sizeof(struct user_regs_struct))
854 ret = putreg(child, addr, data);
855 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
856 addr <= offsetof(struct user, u_debugreg[7])) {
857 addr -= offsetof(struct user, u_debugreg[0]);
858 ret = ptrace_set_debugreg(child,
859 addr / sizeof(data), data);
860 }
861 break;
862
863 case PTRACE_GETREGS: /* Get all gp regs from the child. */
864 return copy_regset_to_user(child,
865 task_user_regset_view(current),
866 REGSET_GENERAL,
867 0, sizeof(struct user_regs_struct),
868 datap);
869
870 case PTRACE_SETREGS: /* Set all gp regs in the child. */
871 return copy_regset_from_user(child,
872 task_user_regset_view(current),
873 REGSET_GENERAL,
874 0, sizeof(struct user_regs_struct),
875 datap);
876
877 case PTRACE_GETFPREGS: /* Get the child FPU state. */
878 return copy_regset_to_user(child,
879 task_user_regset_view(current),
880 REGSET_FP,
881 0, sizeof(struct user_i387_struct),
882 datap);
883
884 case PTRACE_SETFPREGS: /* Set the child FPU state. */
885 return copy_regset_from_user(child,
886 task_user_regset_view(current),
887 REGSET_FP,
888 0, sizeof(struct user_i387_struct),
889 datap);
890
891#ifdef CONFIG_X86_32
892 case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
893 return copy_regset_to_user(child, &user_x86_32_view,
894 REGSET_XFP,
895 0, sizeof(struct user_fxsr_struct),
896 datap) ? -EIO : 0;
897
898 case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
899 return copy_regset_from_user(child, &user_x86_32_view,
900 REGSET_XFP,
901 0, sizeof(struct user_fxsr_struct),
902 datap) ? -EIO : 0;
903#endif
904
905#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
906 case PTRACE_GET_THREAD_AREA:
907 if ((int) addr < 0)
908 return -EIO;
909 ret = do_get_thread_area(child, addr,
910 (struct user_desc __user *)data);
911 break;
912
913 case PTRACE_SET_THREAD_AREA:
914 if ((int) addr < 0)
915 return -EIO;
916 ret = do_set_thread_area(child, addr,
917 (struct user_desc __user *)data, 0);
918 break;
919#endif
920
921#ifdef CONFIG_X86_64
922 /* normal 64bit interface to access TLS data.
923 Works just like arch_prctl, except that the arguments
924 are reversed. */
925 case PTRACE_ARCH_PRCTL:
926 ret = do_arch_prctl(child, data, addr);
927 break;
928#endif
929
930 default:
931 ret = ptrace_request(child, request, addr, data);
932 break;
933 }
934
935 return ret;
936}
937
938#ifdef CONFIG_IA32_EMULATION
939
940#include <linux/compat.h>
941#include <linux/syscalls.h>
942#include <asm/ia32.h>
943#include <asm/user32.h>
944
945#define R32(l,q) \
946 case offsetof(struct user32, regs.l): \
947 regs->q = value; break
948
949#define SEG32(rs) \
950 case offsetof(struct user32, regs.rs): \
951 return set_segment_reg(child, \
952 offsetof(struct user_regs_struct, rs), \
953 value); \
954 break
955
956static int putreg32(struct task_struct *child, unsigned regno, u32 value)
957{
958 struct pt_regs *regs = task_pt_regs(child);
959
960 switch (regno) {
961
962 SEG32(cs);
963 SEG32(ds);
964 SEG32(es);
965 SEG32(fs);
966 SEG32(gs);
967 SEG32(ss);
968
969 R32(ebx, bx);
970 R32(ecx, cx);
971 R32(edx, dx);
972 R32(edi, di);
973 R32(esi, si);
974 R32(ebp, bp);
975 R32(eax, ax);
976 R32(eip, ip);
977 R32(esp, sp);
978
979 case offsetof(struct user32, regs.orig_eax):
980 /*
981 * A 32-bit debugger setting orig_eax means to restore
982 * the state of the task restarting a 32-bit syscall.
983 * Make sure we interpret the -ERESTART* codes correctly
984 * in case the task is not actually still sitting at the
985 * exit from a 32-bit syscall with TS_COMPAT still set.
986 */
987 regs->orig_ax = value;
988 if (syscall_get_nr(child, regs) >= 0)
989 task_thread_info(child)->status |= TS_COMPAT;
990 break;
991
992 case offsetof(struct user32, regs.eflags):
993 return set_flags(child, value);
994
995 case offsetof(struct user32, u_debugreg[0]) ...
996 offsetof(struct user32, u_debugreg[7]):
997 regno -= offsetof(struct user32, u_debugreg[0]);
998 return ptrace_set_debugreg(child, regno / 4, value);
999
1000 default:
1001 if (regno > sizeof(struct user32) || (regno & 3))
1002 return -EIO;
1003
1004 /*
1005 * Other dummy fields in the virtual user structure
1006 * are ignored
1007 */
1008 break;
1009 }
1010 return 0;
1011}
1012
1013#undef R32
1014#undef SEG32
1015
1016#define R32(l,q) \
1017 case offsetof(struct user32, regs.l): \
1018 *val = regs->q; break
1019
1020#define SEG32(rs) \
1021 case offsetof(struct user32, regs.rs): \
1022 *val = get_segment_reg(child, \
1023 offsetof(struct user_regs_struct, rs)); \
1024 break
1025
1026static int getreg32(struct task_struct *child, unsigned regno, u32 *val)
1027{
1028 struct pt_regs *regs = task_pt_regs(child);
1029
1030 switch (regno) {
1031
1032 SEG32(ds);
1033 SEG32(es);
1034 SEG32(fs);
1035 SEG32(gs);
1036
1037 R32(cs, cs);
1038 R32(ss, ss);
1039 R32(ebx, bx);
1040 R32(ecx, cx);
1041 R32(edx, dx);
1042 R32(edi, di);
1043 R32(esi, si);
1044 R32(ebp, bp);
1045 R32(eax, ax);
1046 R32(orig_eax, orig_ax);
1047 R32(eip, ip);
1048 R32(esp, sp);
1049
1050 case offsetof(struct user32, regs.eflags):
1051 *val = get_flags(child);
1052 break;
1053
1054 case offsetof(struct user32, u_debugreg[0]) ...
1055 offsetof(struct user32, u_debugreg[7]):
1056 regno -= offsetof(struct user32, u_debugreg[0]);
1057 *val = ptrace_get_debugreg(child, regno / 4);
1058 break;
1059
1060 default:
1061 if (regno > sizeof(struct user32) || (regno & 3))
1062 return -EIO;
1063
1064 /*
1065 * Other dummy fields in the virtual user structure
1066 * are ignored
1067 */
1068 *val = 0;
1069 break;
1070 }
1071 return 0;
1072}
1073
1074#undef R32
1075#undef SEG32
1076
1077static int genregs32_get(struct task_struct *target,
1078 const struct user_regset *regset,
1079 unsigned int pos, unsigned int count,
1080 void *kbuf, void __user *ubuf)
1081{
1082 if (kbuf) {
1083 compat_ulong_t *k = kbuf;
1084 while (count >= sizeof(*k)) {
1085 getreg32(target, pos, k++);
1086 count -= sizeof(*k);
1087 pos += sizeof(*k);
1088 }
1089 } else {
1090 compat_ulong_t __user *u = ubuf;
1091 while (count >= sizeof(*u)) {
1092 compat_ulong_t word;
1093 getreg32(target, pos, &word);
1094 if (__put_user(word, u++))
1095 return -EFAULT;
1096 count -= sizeof(*u);
1097 pos += sizeof(*u);
1098 }
1099 }
1100
1101 return 0;
1102}
1103
1104static int genregs32_set(struct task_struct *target,
1105 const struct user_regset *regset,
1106 unsigned int pos, unsigned int count,
1107 const void *kbuf, const void __user *ubuf)
1108{
1109 int ret = 0;
1110 if (kbuf) {
1111 const compat_ulong_t *k = kbuf;
1112 while (count >= sizeof(*k) && !ret) {
1113 ret = putreg32(target, pos, *k++);
1114 count -= sizeof(*k);
1115 pos += sizeof(*k);
1116 }
1117 } else {
1118 const compat_ulong_t __user *u = ubuf;
1119 while (count >= sizeof(*u) && !ret) {
1120 compat_ulong_t word;
1121 ret = __get_user(word, u++);
1122 if (ret)
1123 break;
1124 ret = putreg32(target, pos, word);
1125 count -= sizeof(*u);
1126 pos += sizeof(*u);
1127 }
1128 }
1129 return ret;
1130}
1131
1132long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
1133 compat_ulong_t caddr, 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 __u32 val;
1140
1141 switch (request) {
1142 case PTRACE_PEEKUSR:
1143 ret = getreg32(child, addr, &val);
1144 if (ret == 0)
1145 ret = put_user(val, (__u32 __user *)datap);
1146 break;
1147
1148 case PTRACE_POKEUSR:
1149 ret = putreg32(child, addr, data);
1150 break;
1151
1152 case PTRACE_GETREGS: /* Get all gp regs from the child. */
1153 return copy_regset_to_user(child, &user_x86_32_view,
1154 REGSET_GENERAL,
1155 0, sizeof(struct user_regs_struct32),
1156 datap);
1157
1158 case PTRACE_SETREGS: /* Set all gp regs in the child. */
1159 return copy_regset_from_user(child, &user_x86_32_view,
1160 REGSET_GENERAL, 0,
1161 sizeof(struct user_regs_struct32),
1162 datap);
1163
1164 case PTRACE_GETFPREGS: /* Get the child FPU state. */
1165 return copy_regset_to_user(child, &user_x86_32_view,
1166 REGSET_FP, 0,
1167 sizeof(struct user_i387_ia32_struct),
1168 datap);
1169
1170 case PTRACE_SETFPREGS: /* Set the child FPU state. */
1171 return copy_regset_from_user(
1172 child, &user_x86_32_view, REGSET_FP,
1173 0, sizeof(struct user_i387_ia32_struct), datap);
1174
1175 case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
1176 return copy_regset_to_user(child, &user_x86_32_view,
1177 REGSET_XFP, 0,
1178 sizeof(struct user32_fxsr_struct),
1179 datap);
1180
1181 case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
1182 return copy_regset_from_user(child, &user_x86_32_view,
1183 REGSET_XFP, 0,
1184 sizeof(struct user32_fxsr_struct),
1185 datap);
1186
1187 case PTRACE_GET_THREAD_AREA:
1188 case PTRACE_SET_THREAD_AREA:
1189 return arch_ptrace(child, request, addr, data);
1190
1191 default:
1192 return compat_ptrace_request(child, request, addr, data);
1193 }
1194
1195 return ret;
1196}
1197
1198#endif /* CONFIG_IA32_EMULATION */
1199
1200#ifdef CONFIG_X86_64
1201
1202static struct user_regset x86_64_regsets[] __read_mostly = {
1203 [REGSET_GENERAL] = {
1204 .core_note_type = NT_PRSTATUS,
1205 .n = sizeof(struct user_regs_struct) / sizeof(long),
1206 .size = sizeof(long), .align = sizeof(long),
1207 .get = genregs_get, .set = genregs_set
1208 },
1209 [REGSET_FP] = {
1210 .core_note_type = NT_PRFPREG,
1211 .n = sizeof(struct user_i387_struct) / sizeof(long),
1212 .size = sizeof(long), .align = sizeof(long),
1213 .active = xfpregs_active, .get = xfpregs_get, .set = xfpregs_set
1214 },
1215 [REGSET_XSTATE] = {
1216 .core_note_type = NT_X86_XSTATE,
1217 .size = sizeof(u64), .align = sizeof(u64),
1218 .active = xstateregs_active, .get = xstateregs_get,
1219 .set = xstateregs_set
1220 },
1221 [REGSET_IOPERM64] = {
1222 .core_note_type = NT_386_IOPERM,
1223 .n = IO_BITMAP_LONGS,
1224 .size = sizeof(long), .align = sizeof(long),
1225 .active = ioperm_active, .get = ioperm_get
1226 },
1227};
1228
1229static const struct user_regset_view user_x86_64_view = {
1230 .name = "x86_64", .e_machine = EM_X86_64,
1231 .regsets = x86_64_regsets, .n = ARRAY_SIZE(x86_64_regsets)
1232};
1233
1234#else /* CONFIG_X86_32 */
1235
1236#define user_regs_struct32 user_regs_struct
1237#define genregs32_get genregs_get
1238#define genregs32_set genregs_set
1239
1240#define user_i387_ia32_struct user_i387_struct
1241#define user32_fxsr_struct user_fxsr_struct
1242
1243#endif /* CONFIG_X86_64 */
1244
1245#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1246static struct user_regset x86_32_regsets[] __read_mostly = {
1247 [REGSET_GENERAL] = {
1248 .core_note_type = NT_PRSTATUS,
1249 .n = sizeof(struct user_regs_struct32) / sizeof(u32),
1250 .size = sizeof(u32), .align = sizeof(u32),
1251 .get = genregs32_get, .set = genregs32_set
1252 },
1253 [REGSET_FP] = {
1254 .core_note_type = NT_PRFPREG,
1255 .n = sizeof(struct user_i387_ia32_struct) / sizeof(u32),
1256 .size = sizeof(u32), .align = sizeof(u32),
1257 .active = fpregs_active, .get = fpregs_get, .set = fpregs_set
1258 },
1259 [REGSET_XFP] = {
1260 .core_note_type = NT_PRXFPREG,
1261 .n = sizeof(struct user32_fxsr_struct) / sizeof(u32),
1262 .size = sizeof(u32), .align = sizeof(u32),
1263 .active = xfpregs_active, .get = xfpregs_get, .set = xfpregs_set
1264 },
1265 [REGSET_XSTATE] = {
1266 .core_note_type = NT_X86_XSTATE,
1267 .size = sizeof(u64), .align = sizeof(u64),
1268 .active = xstateregs_active, .get = xstateregs_get,
1269 .set = xstateregs_set
1270 },
1271 [REGSET_TLS] = {
1272 .core_note_type = NT_386_TLS,
1273 .n = GDT_ENTRY_TLS_ENTRIES, .bias = GDT_ENTRY_TLS_MIN,
1274 .size = sizeof(struct user_desc),
1275 .align = sizeof(struct user_desc),
1276 .active = regset_tls_active,
1277 .get = regset_tls_get, .set = regset_tls_set
1278 },
1279 [REGSET_IOPERM32] = {
1280 .core_note_type = NT_386_IOPERM,
1281 .n = IO_BITMAP_BYTES / sizeof(u32),
1282 .size = sizeof(u32), .align = sizeof(u32),
1283 .active = ioperm_active, .get = ioperm_get
1284 },
1285};
1286
1287static const struct user_regset_view user_x86_32_view = {
1288 .name = "i386", .e_machine = EM_386,
1289 .regsets = x86_32_regsets, .n = ARRAY_SIZE(x86_32_regsets)
1290};
1291#endif
1292
1293/*
1294 * This represents bytes 464..511 in the memory layout exported through
1295 * the REGSET_XSTATE interface.
1296 */
1297u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
1298
1299void update_regset_xstate_info(unsigned int size, u64 xstate_mask)
1300{
1301#ifdef CONFIG_X86_64
1302 x86_64_regsets[REGSET_XSTATE].n = size / sizeof(u64);
1303#endif
1304#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1305 x86_32_regsets[REGSET_XSTATE].n = size / sizeof(u64);
1306#endif
1307 xstate_fx_sw_bytes[USER_XSTATE_XCR0_WORD] = xstate_mask;
1308}
1309
1310const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1311{
1312#ifdef CONFIG_IA32_EMULATION
1313 if (test_tsk_thread_flag(task, TIF_IA32))
1314#endif
1315#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1316 return &user_x86_32_view;
1317#endif
1318#ifdef CONFIG_X86_64
1319 return &user_x86_64_view;
1320#endif
1321}
1322
1323static void fill_sigtrap_info(struct task_struct *tsk,
1324 struct pt_regs *regs,
1325 int error_code, int si_code,
1326 struct siginfo *info)
1327{
1328 tsk->thread.trap_no = 1;
1329 tsk->thread.error_code = error_code;
1330
1331 memset(info, 0, sizeof(*info));
1332 info->si_signo = SIGTRAP;
1333 info->si_code = si_code;
1334 info->si_addr = user_mode_vm(regs) ? (void __user *)regs->ip : NULL;
1335}
1336
1337void user_single_step_siginfo(struct task_struct *tsk,
1338 struct pt_regs *regs,
1339 struct siginfo *info)
1340{
1341 fill_sigtrap_info(tsk, regs, 0, TRAP_BRKPT, info);
1342}
1343
1344void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs,
1345 int error_code, int si_code)
1346{
1347 struct siginfo info;
1348
1349 fill_sigtrap_info(tsk, regs, error_code, si_code, &info);
1350 /* Send us the fake SIGTRAP */
1351 force_sig_info(SIGTRAP, &info, tsk);
1352}
1353
1354
1355#ifdef CONFIG_X86_32
1356# define IS_IA32 1
1357#elif defined CONFIG_IA32_EMULATION
1358# define IS_IA32 is_compat_task()
1359#else
1360# define IS_IA32 0
1361#endif
1362
1363/*
1364 * We must return the syscall number to actually look up in the table.
1365 * This can be -1L to skip running any syscall at all.
1366 */
1367long syscall_trace_enter(struct pt_regs *regs)
1368{
1369 long ret = 0;
1370
1371 /*
1372 * If we stepped into a sysenter/syscall insn, it trapped in
1373 * kernel mode; do_debug() cleared TF and set TIF_SINGLESTEP.
1374 * If user-mode had set TF itself, then it's still clear from
1375 * do_debug() and we need to set it again to restore the user
1376 * state. If we entered on the slow path, TF was already set.
1377 */
1378 if (test_thread_flag(TIF_SINGLESTEP))
1379 regs->flags |= X86_EFLAGS_TF;
1380
1381 /* do the secure computing check first */
1382 secure_computing(regs->orig_ax);
1383
1384 if (unlikely(test_thread_flag(TIF_SYSCALL_EMU)))
1385 ret = -1L;
1386
1387 if ((ret || test_thread_flag(TIF_SYSCALL_TRACE)) &&
1388 tracehook_report_syscall_entry(regs))
1389 ret = -1L;
1390
1391 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1392 trace_sys_enter(regs, regs->orig_ax);
1393
1394 if (unlikely(current->audit_context)) {
1395 if (IS_IA32)
1396 audit_syscall_entry(AUDIT_ARCH_I386,
1397 regs->orig_ax,
1398 regs->bx, regs->cx,
1399 regs->dx, regs->si);
1400#ifdef CONFIG_X86_64
1401 else
1402 audit_syscall_entry(AUDIT_ARCH_X86_64,
1403 regs->orig_ax,
1404 regs->di, regs->si,
1405 regs->dx, regs->r10);
1406#endif
1407 }
1408
1409 return ret ?: regs->orig_ax;
1410}
1411
1412void syscall_trace_leave(struct pt_regs *regs)
1413{
1414 bool step;
1415
1416 if (unlikely(current->audit_context))
1417 audit_syscall_exit(AUDITSC_RESULT(regs->ax), regs->ax);
1418
1419 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1420 trace_sys_exit(regs, regs->ax);
1421
1422 /*
1423 * If TIF_SYSCALL_EMU is set, we only get here because of
1424 * TIF_SINGLESTEP (i.e. this is PTRACE_SYSEMU_SINGLESTEP).
1425 * We already reported this syscall instruction in
1426 * syscall_trace_enter().
1427 */
1428 step = unlikely(test_thread_flag(TIF_SINGLESTEP)) &&
1429 !test_thread_flag(TIF_SYSCALL_EMU);
1430 if (step || test_thread_flag(TIF_SYSCALL_TRACE))
1431 tracehook_report_syscall_exit(regs, step);
1432}