1
2
3
4
5
6
7
8
9
10
11#include <linux/capability.h>
12#include <linux/export.h>
13#include <linux/sched.h>
14#include <linux/sched/mm.h>
15#include <linux/sched/coredump.h>
16#include <linux/sched/task.h>
17#include <linux/errno.h>
18#include <linux/mm.h>
19#include <linux/highmem.h>
20#include <linux/pagemap.h>
21#include <linux/ptrace.h>
22#include <linux/security.h>
23#include <linux/signal.h>
24#include <linux/uio.h>
25#include <linux/audit.h>
26#include <linux/pid_namespace.h>
27#include <linux/syscalls.h>
28#include <linux/uaccess.h>
29#include <linux/regset.h>
30#include <linux/hw_breakpoint.h>
31#include <linux/cn_proc.h>
32#include <linux/compat.h>
33#include <linux/sched/signal.h>
34
35#include <asm/syscall.h>
36
37
38
39
40
41
42int ptrace_access_vm(struct task_struct *tsk, unsigned long addr,
43 void *buf, int len, unsigned int gup_flags)
44{
45 struct mm_struct *mm;
46 int ret;
47
48 mm = get_task_mm(tsk);
49 if (!mm)
50 return 0;
51
52 if (!tsk->ptrace ||
53 (current != tsk->parent) ||
54 ((get_dumpable(mm) != SUID_DUMP_USER) &&
55 !ptracer_capable(tsk, mm->user_ns))) {
56 mmput(mm);
57 return 0;
58 }
59
60 ret = __access_remote_vm(tsk, mm, addr, buf, len, gup_flags);
61 mmput(mm);
62
63 return ret;
64}
65
66
67void __ptrace_link(struct task_struct *child, struct task_struct *new_parent,
68 const struct cred *ptracer_cred)
69{
70 BUG_ON(!list_empty(&child->ptrace_entry));
71 list_add(&child->ptrace_entry, &new_parent->ptraced);
72 child->parent = new_parent;
73 child->ptracer_cred = get_cred(ptracer_cred);
74}
75
76
77
78
79
80
81
82static void ptrace_link(struct task_struct *child, struct task_struct *new_parent)
83{
84 __ptrace_link(child, new_parent, current_cred());
85}
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115void __ptrace_unlink(struct task_struct *child)
116{
117 const struct cred *old_cred;
118 BUG_ON(!child->ptrace);
119
120 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
121#ifdef TIF_SYSCALL_EMU
122 clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
123#endif
124
125 child->parent = child->real_parent;
126 list_del_init(&child->ptrace_entry);
127 old_cred = child->ptracer_cred;
128 child->ptracer_cred = NULL;
129 put_cred(old_cred);
130
131 spin_lock(&child->sighand->siglock);
132 child->ptrace = 0;
133
134
135
136
137 task_clear_jobctl_pending(child, JOBCTL_TRAP_MASK);
138 task_clear_jobctl_trapping(child);
139
140
141
142
143
144 if (!(child->flags & PF_EXITING) &&
145 (child->signal->flags & SIGNAL_STOP_STOPPED ||
146 child->signal->group_stop_count)) {
147 child->jobctl |= JOBCTL_STOP_PENDING;
148
149
150
151
152
153
154
155
156 if (!(child->jobctl & JOBCTL_STOP_SIGMASK))
157 child->jobctl |= SIGSTOP;
158 }
159
160
161
162
163
164
165
166 if (child->jobctl & JOBCTL_STOP_PENDING || task_is_traced(child))
167 ptrace_signal_wake_up(child, true);
168
169 spin_unlock(&child->sighand->siglock);
170}
171
172
173static bool ptrace_freeze_traced(struct task_struct *task)
174{
175 bool ret = false;
176
177
178 if (task->jobctl & JOBCTL_LISTENING)
179 return ret;
180
181 spin_lock_irq(&task->sighand->siglock);
182 if (task_is_traced(task) && !__fatal_signal_pending(task)) {
183 task->state = __TASK_TRACED;
184 ret = true;
185 }
186 spin_unlock_irq(&task->sighand->siglock);
187
188 return ret;
189}
190
191static void ptrace_unfreeze_traced(struct task_struct *task)
192{
193 if (task->state != __TASK_TRACED)
194 return;
195
196 WARN_ON(!task->ptrace || task->parent != current);
197
198
199
200
201
202 spin_lock_irq(&task->sighand->siglock);
203 if (task->state == __TASK_TRACED) {
204 if (__fatal_signal_pending(task))
205 wake_up_state(task, __TASK_TRACED);
206 else
207 task->state = TASK_TRACED;
208 }
209 spin_unlock_irq(&task->sighand->siglock);
210}
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229static int ptrace_check_attach(struct task_struct *child, bool ignore_state)
230{
231 int ret = -ESRCH;
232
233
234
235
236
237
238
239
240 read_lock(&tasklist_lock);
241 if (child->ptrace && child->parent == current) {
242 WARN_ON(child->state == __TASK_TRACED);
243
244
245
246
247 if (ignore_state || ptrace_freeze_traced(child))
248 ret = 0;
249 }
250 read_unlock(&tasklist_lock);
251
252 if (!ret && !ignore_state) {
253 if (!wait_task_inactive(child, __TASK_TRACED)) {
254
255
256
257
258
259 WARN_ON(child->state == __TASK_TRACED);
260 ret = -ESRCH;
261 }
262 }
263
264 return ret;
265}
266
267static int ptrace_has_cap(struct user_namespace *ns, unsigned int mode)
268{
269 if (mode & PTRACE_MODE_NOAUDIT)
270 return has_ns_capability_noaudit(current, ns, CAP_SYS_PTRACE);
271 else
272 return has_ns_capability(current, ns, CAP_SYS_PTRACE);
273}
274
275
276static int __ptrace_may_access(struct task_struct *task, unsigned int mode)
277{
278 const struct cred *cred = current_cred(), *tcred;
279 struct mm_struct *mm;
280 kuid_t caller_uid;
281 kgid_t caller_gid;
282
283 if (!(mode & PTRACE_MODE_FSCREDS) == !(mode & PTRACE_MODE_REALCREDS)) {
284 WARN(1, "denying ptrace access check without PTRACE_MODE_*CREDS\n");
285 return -EPERM;
286 }
287
288
289
290
291
292
293
294
295
296
297
298 if (same_thread_group(task, current))
299 return 0;
300 rcu_read_lock();
301 if (mode & PTRACE_MODE_FSCREDS) {
302 caller_uid = cred->fsuid;
303 caller_gid = cred->fsgid;
304 } else {
305
306
307
308
309
310
311
312
313 caller_uid = cred->uid;
314 caller_gid = cred->gid;
315 }
316 tcred = __task_cred(task);
317 if (uid_eq(caller_uid, tcred->euid) &&
318 uid_eq(caller_uid, tcred->suid) &&
319 uid_eq(caller_uid, tcred->uid) &&
320 gid_eq(caller_gid, tcred->egid) &&
321 gid_eq(caller_gid, tcred->sgid) &&
322 gid_eq(caller_gid, tcred->gid))
323 goto ok;
324 if (ptrace_has_cap(tcred->user_ns, mode))
325 goto ok;
326 rcu_read_unlock();
327 return -EPERM;
328ok:
329 rcu_read_unlock();
330
331
332
333
334
335
336
337
338
339 smp_rmb();
340 mm = task->mm;
341 if (mm &&
342 ((get_dumpable(mm) != SUID_DUMP_USER) &&
343 !ptrace_has_cap(mm->user_ns, mode)))
344 return -EPERM;
345
346 return security_ptrace_access_check(task, mode);
347}
348
349bool ptrace_may_access(struct task_struct *task, unsigned int mode)
350{
351 int err;
352 task_lock(task);
353 err = __ptrace_may_access(task, mode);
354 task_unlock(task);
355 return !err;
356}
357
358static int ptrace_attach(struct task_struct *task, long request,
359 unsigned long addr,
360 unsigned long flags)
361{
362 bool seize = (request == PTRACE_SEIZE);
363 int retval;
364
365 retval = -EIO;
366 if (seize) {
367 if (addr != 0)
368 goto out;
369 if (flags & ~(unsigned long)PTRACE_O_MASK)
370 goto out;
371 flags = PT_PTRACED | PT_SEIZED | (flags << PT_OPT_FLAG_SHIFT);
372 } else {
373 flags = PT_PTRACED;
374 }
375
376 audit_ptrace(task);
377
378 retval = -EPERM;
379 if (unlikely(task->flags & PF_KTHREAD))
380 goto out;
381 if (same_thread_group(task, current))
382 goto out;
383
384
385
386
387
388
389 retval = -ERESTARTNOINTR;
390 if (mutex_lock_interruptible(&task->signal->cred_guard_mutex))
391 goto out;
392
393 task_lock(task);
394 retval = __ptrace_may_access(task, PTRACE_MODE_ATTACH_REALCREDS);
395 task_unlock(task);
396 if (retval)
397 goto unlock_creds;
398
399 write_lock_irq(&tasklist_lock);
400 retval = -EPERM;
401 if (unlikely(task->exit_state))
402 goto unlock_tasklist;
403 if (task->ptrace)
404 goto unlock_tasklist;
405
406 if (seize)
407 flags |= PT_SEIZED;
408 task->ptrace = flags;
409
410 ptrace_link(task, current);
411
412
413 if (!seize)
414 send_sig_info(SIGSTOP, SEND_SIG_PRIV, task);
415
416 spin_lock(&task->sighand->siglock);
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435 if (task_is_stopped(task) &&
436 task_set_jobctl_pending(task, JOBCTL_TRAP_STOP | JOBCTL_TRAPPING))
437 signal_wake_up_state(task, __TASK_STOPPED);
438
439 spin_unlock(&task->sighand->siglock);
440
441 retval = 0;
442unlock_tasklist:
443 write_unlock_irq(&tasklist_lock);
444unlock_creds:
445 mutex_unlock(&task->signal->cred_guard_mutex);
446out:
447 if (!retval) {
448
449
450
451
452
453
454
455 wait_on_bit(&task->jobctl, JOBCTL_TRAPPING_BIT, TASK_KILLABLE);
456 proc_ptrace_connector(task, PTRACE_ATTACH);
457 }
458
459 return retval;
460}
461
462
463
464
465
466
467
468static int ptrace_traceme(void)
469{
470 int ret = -EPERM;
471
472 write_lock_irq(&tasklist_lock);
473
474 if (!current->ptrace) {
475 ret = security_ptrace_traceme(current->parent);
476
477
478
479
480
481 if (!ret && !(current->real_parent->flags & PF_EXITING)) {
482 current->ptrace = PT_PTRACED;
483 ptrace_link(current, current->real_parent);
484 }
485 }
486 write_unlock_irq(&tasklist_lock);
487
488 return ret;
489}
490
491
492
493
494static int ignoring_children(struct sighand_struct *sigh)
495{
496 int ret;
497 spin_lock(&sigh->siglock);
498 ret = (sigh->action[SIGCHLD-1].sa.sa_handler == SIG_IGN) ||
499 (sigh->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT);
500 spin_unlock(&sigh->siglock);
501 return ret;
502}
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519static bool __ptrace_detach(struct task_struct *tracer, struct task_struct *p)
520{
521 bool dead;
522
523 __ptrace_unlink(p);
524
525 if (p->exit_state != EXIT_ZOMBIE)
526 return false;
527
528 dead = !thread_group_leader(p);
529
530 if (!dead && thread_group_empty(p)) {
531 if (!same_thread_group(p->real_parent, tracer))
532 dead = do_notify_parent(p, p->exit_signal);
533 else if (ignoring_children(tracer->sighand)) {
534 __wake_up_parent(p, tracer);
535 dead = true;
536 }
537 }
538
539 if (dead)
540 p->exit_state = EXIT_DEAD;
541 return dead;
542}
543
544static int ptrace_detach(struct task_struct *child, unsigned int data)
545{
546 if (!valid_signal(data))
547 return -EIO;
548
549
550 ptrace_disable(child);
551
552 write_lock_irq(&tasklist_lock);
553
554
555
556
557 WARN_ON(!child->ptrace || child->exit_state);
558
559
560
561
562 child->exit_code = data;
563 __ptrace_detach(current, child);
564 write_unlock_irq(&tasklist_lock);
565
566 proc_ptrace_connector(child, PTRACE_DETACH);
567
568 return 0;
569}
570
571
572
573
574
575void exit_ptrace(struct task_struct *tracer, struct list_head *dead)
576{
577 struct task_struct *p, *n;
578
579 list_for_each_entry_safe(p, n, &tracer->ptraced, ptrace_entry) {
580 if (unlikely(p->ptrace & PT_EXITKILL))
581 send_sig_info(SIGKILL, SEND_SIG_PRIV, p);
582
583 if (__ptrace_detach(tracer, p))
584 list_add(&p->ptrace_entry, dead);
585 }
586}
587
588int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len)
589{
590 int copied = 0;
591
592 while (len > 0) {
593 char buf[128];
594 int this_len, retval;
595
596 this_len = (len > sizeof(buf)) ? sizeof(buf) : len;
597 retval = ptrace_access_vm(tsk, src, buf, this_len, FOLL_FORCE);
598
599 if (!retval) {
600 if (copied)
601 break;
602 return -EIO;
603 }
604 if (copy_to_user(dst, buf, retval))
605 return -EFAULT;
606 copied += retval;
607 src += retval;
608 dst += retval;
609 len -= retval;
610 }
611 return copied;
612}
613
614int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len)
615{
616 int copied = 0;
617
618 while (len > 0) {
619 char buf[128];
620 int this_len, retval;
621
622 this_len = (len > sizeof(buf)) ? sizeof(buf) : len;
623 if (copy_from_user(buf, src, this_len))
624 return -EFAULT;
625 retval = ptrace_access_vm(tsk, dst, buf, this_len,
626 FOLL_FORCE | FOLL_WRITE);
627 if (!retval) {
628 if (copied)
629 break;
630 return -EIO;
631 }
632 copied += retval;
633 src += retval;
634 dst += retval;
635 len -= retval;
636 }
637 return copied;
638}
639
640static int ptrace_setoptions(struct task_struct *child, unsigned long data)
641{
642 unsigned flags;
643
644 if (data & ~(unsigned long)PTRACE_O_MASK)
645 return -EINVAL;
646
647 if (unlikely(data & PTRACE_O_SUSPEND_SECCOMP)) {
648 if (!IS_ENABLED(CONFIG_CHECKPOINT_RESTORE) ||
649 !IS_ENABLED(CONFIG_SECCOMP))
650 return -EINVAL;
651
652 if (!capable(CAP_SYS_ADMIN))
653 return -EPERM;
654
655 if (seccomp_mode(¤t->seccomp) != SECCOMP_MODE_DISABLED ||
656 current->ptrace & PT_SUSPEND_SECCOMP)
657 return -EPERM;
658 }
659
660
661 flags = child->ptrace;
662 flags &= ~(PTRACE_O_MASK << PT_OPT_FLAG_SHIFT);
663 flags |= (data << PT_OPT_FLAG_SHIFT);
664 child->ptrace = flags;
665
666 return 0;
667}
668
669static int ptrace_getsiginfo(struct task_struct *child, kernel_siginfo_t *info)
670{
671 unsigned long flags;
672 int error = -ESRCH;
673
674 if (lock_task_sighand(child, &flags)) {
675 error = -EINVAL;
676 if (likely(child->last_siginfo != NULL)) {
677 copy_siginfo(info, child->last_siginfo);
678 error = 0;
679 }
680 unlock_task_sighand(child, &flags);
681 }
682 return error;
683}
684
685static int ptrace_setsiginfo(struct task_struct *child, const kernel_siginfo_t *info)
686{
687 unsigned long flags;
688 int error = -ESRCH;
689
690 if (lock_task_sighand(child, &flags)) {
691 error = -EINVAL;
692 if (likely(child->last_siginfo != NULL)) {
693 copy_siginfo(child->last_siginfo, info);
694 error = 0;
695 }
696 unlock_task_sighand(child, &flags);
697 }
698 return error;
699}
700
701static int ptrace_peek_siginfo(struct task_struct *child,
702 unsigned long addr,
703 unsigned long data)
704{
705 struct ptrace_peeksiginfo_args arg;
706 struct sigpending *pending;
707 struct sigqueue *q;
708 int ret, i;
709
710 ret = copy_from_user(&arg, (void __user *) addr,
711 sizeof(struct ptrace_peeksiginfo_args));
712 if (ret)
713 return -EFAULT;
714
715 if (arg.flags & ~PTRACE_PEEKSIGINFO_SHARED)
716 return -EINVAL;
717
718 if (arg.nr < 0)
719 return -EINVAL;
720
721
722 if (arg.off > ULONG_MAX)
723 return 0;
724
725 if (arg.flags & PTRACE_PEEKSIGINFO_SHARED)
726 pending = &child->signal->shared_pending;
727 else
728 pending = &child->pending;
729
730 for (i = 0; i < arg.nr; ) {
731 kernel_siginfo_t info;
732 unsigned long off = arg.off + i;
733 bool found = false;
734
735 spin_lock_irq(&child->sighand->siglock);
736 list_for_each_entry(q, &pending->list, list) {
737 if (!off--) {
738 found = true;
739 copy_siginfo(&info, &q->info);
740 break;
741 }
742 }
743 spin_unlock_irq(&child->sighand->siglock);
744
745 if (!found)
746 break;
747
748#ifdef CONFIG_COMPAT
749 if (unlikely(in_compat_syscall())) {
750 compat_siginfo_t __user *uinfo = compat_ptr(data);
751
752 if (copy_siginfo_to_user32(uinfo, &info)) {
753 ret = -EFAULT;
754 break;
755 }
756
757 } else
758#endif
759 {
760 siginfo_t __user *uinfo = (siginfo_t __user *) data;
761
762 if (copy_siginfo_to_user(uinfo, &info)) {
763 ret = -EFAULT;
764 break;
765 }
766 }
767
768 data += sizeof(siginfo_t);
769 i++;
770
771 if (signal_pending(current))
772 break;
773
774 cond_resched();
775 }
776
777 if (i > 0)
778 return i;
779
780 return ret;
781}
782
783#ifdef PTRACE_SINGLESTEP
784#define is_singlestep(request) ((request) == PTRACE_SINGLESTEP)
785#else
786#define is_singlestep(request) 0
787#endif
788
789#ifdef PTRACE_SINGLEBLOCK
790#define is_singleblock(request) ((request) == PTRACE_SINGLEBLOCK)
791#else
792#define is_singleblock(request) 0
793#endif
794
795#ifdef PTRACE_SYSEMU
796#define is_sysemu_singlestep(request) ((request) == PTRACE_SYSEMU_SINGLESTEP)
797#else
798#define is_sysemu_singlestep(request) 0
799#endif
800
801static int ptrace_resume(struct task_struct *child, long request,
802 unsigned long data)
803{
804 bool need_siglock;
805
806 if (!valid_signal(data))
807 return -EIO;
808
809 if (request == PTRACE_SYSCALL)
810 set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
811 else
812 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
813
814#ifdef TIF_SYSCALL_EMU
815 if (request == PTRACE_SYSEMU || request == PTRACE_SYSEMU_SINGLESTEP)
816 set_tsk_thread_flag(child, TIF_SYSCALL_EMU);
817 else
818 clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
819#endif
820
821 if (is_singleblock(request)) {
822 if (unlikely(!arch_has_block_step()))
823 return -EIO;
824 user_enable_block_step(child);
825 } else if (is_singlestep(request) || is_sysemu_singlestep(request)) {
826 if (unlikely(!arch_has_single_step()))
827 return -EIO;
828 user_enable_single_step(child);
829 } else {
830 user_disable_single_step(child);
831 }
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846 need_siglock = data && !thread_group_empty(current);
847 if (need_siglock)
848 spin_lock_irq(&child->sighand->siglock);
849 child->exit_code = data;
850 wake_up_state(child, __TASK_TRACED);
851 if (need_siglock)
852 spin_unlock_irq(&child->sighand->siglock);
853
854 return 0;
855}
856
857#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
858
859static const struct user_regset *
860find_regset(const struct user_regset_view *view, unsigned int type)
861{
862 const struct user_regset *regset;
863 int n;
864
865 for (n = 0; n < view->n; ++n) {
866 regset = view->regsets + n;
867 if (regset->core_note_type == type)
868 return regset;
869 }
870
871 return NULL;
872}
873
874static int ptrace_regset(struct task_struct *task, int req, unsigned int type,
875 struct iovec *kiov)
876{
877 const struct user_regset_view *view = task_user_regset_view(task);
878 const struct user_regset *regset = find_regset(view, type);
879 int regset_no;
880
881 if (!regset || (kiov->iov_len % regset->size) != 0)
882 return -EINVAL;
883
884 regset_no = regset - view->regsets;
885 kiov->iov_len = min(kiov->iov_len,
886 (__kernel_size_t) (regset->n * regset->size));
887
888 if (req == PTRACE_GETREGSET)
889 return copy_regset_to_user(task, view, regset_no, 0,
890 kiov->iov_len, kiov->iov_base);
891 else
892 return copy_regset_from_user(task, view, regset_no, 0,
893 kiov->iov_len, kiov->iov_base);
894}
895
896
897
898
899
900
901EXPORT_SYMBOL_GPL(task_user_regset_view);
902
903static unsigned long
904ptrace_get_syscall_info_entry(struct task_struct *child, struct pt_regs *regs,
905 struct ptrace_syscall_info *info)
906{
907 unsigned long args[ARRAY_SIZE(info->entry.args)];
908 int i;
909
910 info->op = PTRACE_SYSCALL_INFO_ENTRY;
911 info->entry.nr = syscall_get_nr(child, regs);
912 syscall_get_arguments(child, regs, args);
913 for (i = 0; i < ARRAY_SIZE(args); i++)
914 info->entry.args[i] = args[i];
915
916
917 return offsetofend(struct ptrace_syscall_info, entry.args);
918}
919
920static unsigned long
921ptrace_get_syscall_info_seccomp(struct task_struct *child, struct pt_regs *regs,
922 struct ptrace_syscall_info *info)
923{
924
925
926
927
928
929
930
931 ptrace_get_syscall_info_entry(child, regs, info);
932 info->op = PTRACE_SYSCALL_INFO_SECCOMP;
933 info->seccomp.ret_data = child->ptrace_message;
934
935
936 return offsetofend(struct ptrace_syscall_info, seccomp.ret_data);
937}
938
939static unsigned long
940ptrace_get_syscall_info_exit(struct task_struct *child, struct pt_regs *regs,
941 struct ptrace_syscall_info *info)
942{
943 info->op = PTRACE_SYSCALL_INFO_EXIT;
944 info->exit.rval = syscall_get_error(child, regs);
945 info->exit.is_error = !!info->exit.rval;
946 if (!info->exit.is_error)
947 info->exit.rval = syscall_get_return_value(child, regs);
948
949
950 return offsetofend(struct ptrace_syscall_info, exit.is_error);
951}
952
953static int
954ptrace_get_syscall_info(struct task_struct *child, unsigned long user_size,
955 void __user *datavp)
956{
957 struct pt_regs *regs = task_pt_regs(child);
958 struct ptrace_syscall_info info = {
959 .op = PTRACE_SYSCALL_INFO_NONE,
960 .arch = syscall_get_arch(child),
961 .instruction_pointer = instruction_pointer(regs),
962 .stack_pointer = user_stack_pointer(regs),
963 };
964 unsigned long actual_size = offsetof(struct ptrace_syscall_info, entry);
965 unsigned long write_size;
966
967
968
969
970
971
972
973 switch (child->last_siginfo ? child->last_siginfo->si_code : 0) {
974 case SIGTRAP | 0x80:
975 switch (child->ptrace_message) {
976 case PTRACE_EVENTMSG_SYSCALL_ENTRY:
977 actual_size = ptrace_get_syscall_info_entry(child, regs,
978 &info);
979 break;
980 case PTRACE_EVENTMSG_SYSCALL_EXIT:
981 actual_size = ptrace_get_syscall_info_exit(child, regs,
982 &info);
983 break;
984 }
985 break;
986 case SIGTRAP | (PTRACE_EVENT_SECCOMP << 8):
987 actual_size = ptrace_get_syscall_info_seccomp(child, regs,
988 &info);
989 break;
990 }
991
992 write_size = min(actual_size, user_size);
993 return copy_to_user(datavp, &info, write_size) ? -EFAULT : actual_size;
994}
995#endif
996
997int ptrace_request(struct task_struct *child, long request,
998 unsigned long addr, unsigned long data)
999{
1000 bool seized = child->ptrace & PT_SEIZED;
1001 int ret = -EIO;
1002 kernel_siginfo_t siginfo, *si;
1003 void __user *datavp = (void __user *) data;
1004 unsigned long __user *datalp = datavp;
1005 unsigned long flags;
1006
1007 switch (request) {
1008 case PTRACE_PEEKTEXT:
1009 case PTRACE_PEEKDATA:
1010 return generic_ptrace_peekdata(child, addr, data);
1011 case PTRACE_POKETEXT:
1012 case PTRACE_POKEDATA:
1013 return generic_ptrace_pokedata(child, addr, data);
1014
1015#ifdef PTRACE_OLDSETOPTIONS
1016 case PTRACE_OLDSETOPTIONS:
1017#endif
1018 case PTRACE_SETOPTIONS:
1019 ret = ptrace_setoptions(child, data);
1020 break;
1021 case PTRACE_GETEVENTMSG:
1022 ret = put_user(child->ptrace_message, datalp);
1023 break;
1024
1025 case PTRACE_PEEKSIGINFO:
1026 ret = ptrace_peek_siginfo(child, addr, data);
1027 break;
1028
1029 case PTRACE_GETSIGINFO:
1030 ret = ptrace_getsiginfo(child, &siginfo);
1031 if (!ret)
1032 ret = copy_siginfo_to_user(datavp, &siginfo);
1033 break;
1034
1035 case PTRACE_SETSIGINFO:
1036 ret = copy_siginfo_from_user(&siginfo, datavp);
1037 if (!ret)
1038 ret = ptrace_setsiginfo(child, &siginfo);
1039 break;
1040
1041 case PTRACE_GETSIGMASK: {
1042 sigset_t *mask;
1043
1044 if (addr != sizeof(sigset_t)) {
1045 ret = -EINVAL;
1046 break;
1047 }
1048
1049 if (test_tsk_restore_sigmask(child))
1050 mask = &child->saved_sigmask;
1051 else
1052 mask = &child->blocked;
1053
1054 if (copy_to_user(datavp, mask, sizeof(sigset_t)))
1055 ret = -EFAULT;
1056 else
1057 ret = 0;
1058
1059 break;
1060 }
1061
1062 case PTRACE_SETSIGMASK: {
1063 sigset_t new_set;
1064
1065 if (addr != sizeof(sigset_t)) {
1066 ret = -EINVAL;
1067 break;
1068 }
1069
1070 if (copy_from_user(&new_set, datavp, sizeof(sigset_t))) {
1071 ret = -EFAULT;
1072 break;
1073 }
1074
1075 sigdelsetmask(&new_set, sigmask(SIGKILL)|sigmask(SIGSTOP));
1076
1077
1078
1079
1080
1081
1082 spin_lock_irq(&child->sighand->siglock);
1083 child->blocked = new_set;
1084 spin_unlock_irq(&child->sighand->siglock);
1085
1086 clear_tsk_restore_sigmask(child);
1087
1088 ret = 0;
1089 break;
1090 }
1091
1092 case PTRACE_INTERRUPT:
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103 if (unlikely(!seized || !lock_task_sighand(child, &flags)))
1104 break;
1105
1106
1107
1108
1109
1110
1111
1112 if (likely(task_set_jobctl_pending(child, JOBCTL_TRAP_STOP)))
1113 ptrace_signal_wake_up(child, child->jobctl & JOBCTL_LISTENING);
1114
1115 unlock_task_sighand(child, &flags);
1116 ret = 0;
1117 break;
1118
1119 case PTRACE_LISTEN:
1120
1121
1122
1123
1124
1125
1126
1127
1128 if (unlikely(!seized || !lock_task_sighand(child, &flags)))
1129 break;
1130
1131 si = child->last_siginfo;
1132 if (likely(si && (si->si_code >> 8) == PTRACE_EVENT_STOP)) {
1133 child->jobctl |= JOBCTL_LISTENING;
1134
1135
1136
1137
1138 if (child->jobctl & JOBCTL_TRAP_NOTIFY)
1139 ptrace_signal_wake_up(child, true);
1140 ret = 0;
1141 }
1142 unlock_task_sighand(child, &flags);
1143 break;
1144
1145 case PTRACE_DETACH:
1146 ret = ptrace_detach(child, data);
1147 break;
1148
1149#ifdef CONFIG_BINFMT_ELF_FDPIC
1150 case PTRACE_GETFDPIC: {
1151 struct mm_struct *mm = get_task_mm(child);
1152 unsigned long tmp = 0;
1153
1154 ret = -ESRCH;
1155 if (!mm)
1156 break;
1157
1158 switch (addr) {
1159 case PTRACE_GETFDPIC_EXEC:
1160 tmp = mm->context.exec_fdpic_loadmap;
1161 break;
1162 case PTRACE_GETFDPIC_INTERP:
1163 tmp = mm->context.interp_fdpic_loadmap;
1164 break;
1165 default:
1166 break;
1167 }
1168 mmput(mm);
1169
1170 ret = put_user(tmp, datalp);
1171 break;
1172 }
1173#endif
1174
1175#ifdef PTRACE_SINGLESTEP
1176 case PTRACE_SINGLESTEP:
1177#endif
1178#ifdef PTRACE_SINGLEBLOCK
1179 case PTRACE_SINGLEBLOCK:
1180#endif
1181#ifdef PTRACE_SYSEMU
1182 case PTRACE_SYSEMU:
1183 case PTRACE_SYSEMU_SINGLESTEP:
1184#endif
1185 case PTRACE_SYSCALL:
1186 case PTRACE_CONT:
1187 return ptrace_resume(child, request, data);
1188
1189 case PTRACE_KILL:
1190 if (child->exit_state)
1191 return 0;
1192 return ptrace_resume(child, request, SIGKILL);
1193
1194#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
1195 case PTRACE_GETREGSET:
1196 case PTRACE_SETREGSET: {
1197 struct iovec kiov;
1198 struct iovec __user *uiov = datavp;
1199
1200 if (!access_ok(uiov, sizeof(*uiov)))
1201 return -EFAULT;
1202
1203 if (__get_user(kiov.iov_base, &uiov->iov_base) ||
1204 __get_user(kiov.iov_len, &uiov->iov_len))
1205 return -EFAULT;
1206
1207 ret = ptrace_regset(child, request, addr, &kiov);
1208 if (!ret)
1209 ret = __put_user(kiov.iov_len, &uiov->iov_len);
1210 break;
1211 }
1212
1213 case PTRACE_GET_SYSCALL_INFO:
1214 ret = ptrace_get_syscall_info(child, addr, datavp);
1215 break;
1216#endif
1217
1218 case PTRACE_SECCOMP_GET_FILTER:
1219 ret = seccomp_get_filter(child, addr, datavp);
1220 break;
1221
1222 case PTRACE_SECCOMP_GET_METADATA:
1223 ret = seccomp_get_metadata(child, addr, datavp);
1224 break;
1225
1226 default:
1227 break;
1228 }
1229
1230 return ret;
1231}
1232
1233#ifndef arch_ptrace_attach
1234#define arch_ptrace_attach(child) do { } while (0)
1235#endif
1236
1237SYSCALL_DEFINE4(ptrace, long, request, long, pid, unsigned long, addr,
1238 unsigned long, data)
1239{
1240 struct task_struct *child;
1241 long ret;
1242
1243 if (request == PTRACE_TRACEME) {
1244 ret = ptrace_traceme();
1245 if (!ret)
1246 arch_ptrace_attach(current);
1247 goto out;
1248 }
1249
1250 child = find_get_task_by_vpid(pid);
1251 if (!child) {
1252 ret = -ESRCH;
1253 goto out;
1254 }
1255
1256 if (request == PTRACE_ATTACH || request == PTRACE_SEIZE) {
1257 ret = ptrace_attach(child, request, addr, data);
1258
1259
1260
1261
1262 if (!ret)
1263 arch_ptrace_attach(child);
1264 goto out_put_task_struct;
1265 }
1266
1267 ret = ptrace_check_attach(child, request == PTRACE_KILL ||
1268 request == PTRACE_INTERRUPT);
1269 if (ret < 0)
1270 goto out_put_task_struct;
1271
1272 ret = arch_ptrace(child, request, addr, data);
1273 if (ret || request != PTRACE_DETACH)
1274 ptrace_unfreeze_traced(child);
1275
1276 out_put_task_struct:
1277 put_task_struct(child);
1278 out:
1279 return ret;
1280}
1281
1282int generic_ptrace_peekdata(struct task_struct *tsk, unsigned long addr,
1283 unsigned long data)
1284{
1285 unsigned long tmp;
1286 int copied;
1287
1288 copied = ptrace_access_vm(tsk, addr, &tmp, sizeof(tmp), FOLL_FORCE);
1289 if (copied != sizeof(tmp))
1290 return -EIO;
1291 return put_user(tmp, (unsigned long __user *)data);
1292}
1293
1294int generic_ptrace_pokedata(struct task_struct *tsk, unsigned long addr,
1295 unsigned long data)
1296{
1297 int copied;
1298
1299 copied = ptrace_access_vm(tsk, addr, &data, sizeof(data),
1300 FOLL_FORCE | FOLL_WRITE);
1301 return (copied == sizeof(data)) ? 0 : -EIO;
1302}
1303
1304#if defined CONFIG_COMPAT
1305
1306int compat_ptrace_request(struct task_struct *child, compat_long_t request,
1307 compat_ulong_t addr, compat_ulong_t data)
1308{
1309 compat_ulong_t __user *datap = compat_ptr(data);
1310 compat_ulong_t word;
1311 kernel_siginfo_t siginfo;
1312 int ret;
1313
1314 switch (request) {
1315 case PTRACE_PEEKTEXT:
1316 case PTRACE_PEEKDATA:
1317 ret = ptrace_access_vm(child, addr, &word, sizeof(word),
1318 FOLL_FORCE);
1319 if (ret != sizeof(word))
1320 ret = -EIO;
1321 else
1322 ret = put_user(word, datap);
1323 break;
1324
1325 case PTRACE_POKETEXT:
1326 case PTRACE_POKEDATA:
1327 ret = ptrace_access_vm(child, addr, &data, sizeof(data),
1328 FOLL_FORCE | FOLL_WRITE);
1329 ret = (ret != sizeof(data) ? -EIO : 0);
1330 break;
1331
1332 case PTRACE_GETEVENTMSG:
1333 ret = put_user((compat_ulong_t) child->ptrace_message, datap);
1334 break;
1335
1336 case PTRACE_GETSIGINFO:
1337 ret = ptrace_getsiginfo(child, &siginfo);
1338 if (!ret)
1339 ret = copy_siginfo_to_user32(
1340 (struct compat_siginfo __user *) datap,
1341 &siginfo);
1342 break;
1343
1344 case PTRACE_SETSIGINFO:
1345 ret = copy_siginfo_from_user32(
1346 &siginfo, (struct compat_siginfo __user *) datap);
1347 if (!ret)
1348 ret = ptrace_setsiginfo(child, &siginfo);
1349 break;
1350#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
1351 case PTRACE_GETREGSET:
1352 case PTRACE_SETREGSET:
1353 {
1354 struct iovec kiov;
1355 struct compat_iovec __user *uiov =
1356 (struct compat_iovec __user *) datap;
1357 compat_uptr_t ptr;
1358 compat_size_t len;
1359
1360 if (!access_ok(uiov, sizeof(*uiov)))
1361 return -EFAULT;
1362
1363 if (__get_user(ptr, &uiov->iov_base) ||
1364 __get_user(len, &uiov->iov_len))
1365 return -EFAULT;
1366
1367 kiov.iov_base = compat_ptr(ptr);
1368 kiov.iov_len = len;
1369
1370 ret = ptrace_regset(child, request, addr, &kiov);
1371 if (!ret)
1372 ret = __put_user(kiov.iov_len, &uiov->iov_len);
1373 break;
1374 }
1375#endif
1376
1377 default:
1378 ret = ptrace_request(child, request, addr, data);
1379 }
1380
1381 return ret;
1382}
1383
1384COMPAT_SYSCALL_DEFINE4(ptrace, compat_long_t, request, compat_long_t, pid,
1385 compat_long_t, addr, compat_long_t, data)
1386{
1387 struct task_struct *child;
1388 long ret;
1389
1390 if (request == PTRACE_TRACEME) {
1391 ret = ptrace_traceme();
1392 goto out;
1393 }
1394
1395 child = find_get_task_by_vpid(pid);
1396 if (!child) {
1397 ret = -ESRCH;
1398 goto out;
1399 }
1400
1401 if (request == PTRACE_ATTACH || request == PTRACE_SEIZE) {
1402 ret = ptrace_attach(child, request, addr, data);
1403
1404
1405
1406
1407 if (!ret)
1408 arch_ptrace_attach(child);
1409 goto out_put_task_struct;
1410 }
1411
1412 ret = ptrace_check_attach(child, request == PTRACE_KILL ||
1413 request == PTRACE_INTERRUPT);
1414 if (!ret) {
1415 ret = compat_arch_ptrace(child, request, addr, data);
1416 if (ret || request != PTRACE_DETACH)
1417 ptrace_unfreeze_traced(child);
1418 }
1419
1420 out_put_task_struct:
1421 put_task_struct(child);
1422 out:
1423 return ret;
1424}
1425#endif
1426