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10#include <linux/capability.h>
11#include <linux/export.h>
12#include <linux/sched.h>
13#include <linux/errno.h>
14#include <linux/mm.h>
15#include <linux/highmem.h>
16#include <linux/pagemap.h>
17#include <linux/ptrace.h>
18#include <linux/security.h>
19#include <linux/signal.h>
20#include <linux/uio.h>
21#include <linux/audit.h>
22#include <linux/pid_namespace.h>
23#include <linux/syscalls.h>
24#include <linux/uaccess.h>
25#include <linux/regset.h>
26#include <linux/hw_breakpoint.h>
27#include <linux/cn_proc.h>
28#include <linux/compat.h>
29
30
31
32
33
34
35
36
37void __ptrace_link(struct task_struct *child, struct task_struct *new_parent)
38{
39 BUG_ON(!list_empty(&child->ptrace_entry));
40 list_add(&child->ptrace_entry, &new_parent->ptraced);
41 child->parent = new_parent;
42}
43
44
45
46
47
48
49
50
51
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53
54
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69
70
71
72void __ptrace_unlink(struct task_struct *child)
73{
74 BUG_ON(!child->ptrace);
75
76 child->parent = child->real_parent;
77 list_del_init(&child->ptrace_entry);
78
79 spin_lock(&child->sighand->siglock);
80 child->ptrace = 0;
81
82
83
84
85 task_clear_jobctl_pending(child, JOBCTL_TRAP_MASK);
86 task_clear_jobctl_trapping(child);
87
88
89
90
91
92 if (!(child->flags & PF_EXITING) &&
93 (child->signal->flags & SIGNAL_STOP_STOPPED ||
94 child->signal->group_stop_count)) {
95 child->jobctl |= JOBCTL_STOP_PENDING;
96
97
98
99
100
101
102
103
104 if (!(child->jobctl & JOBCTL_STOP_SIGMASK))
105 child->jobctl |= SIGSTOP;
106 }
107
108
109
110
111
112
113
114 if (child->jobctl & JOBCTL_STOP_PENDING || task_is_traced(child))
115 ptrace_signal_wake_up(child, true);
116
117 spin_unlock(&child->sighand->siglock);
118}
119
120
121static bool ptrace_freeze_traced(struct task_struct *task)
122{
123 bool ret = false;
124
125
126 if (task->jobctl & JOBCTL_LISTENING)
127 return ret;
128
129 spin_lock_irq(&task->sighand->siglock);
130 if (task_is_traced(task) && !__fatal_signal_pending(task)) {
131 task->state = __TASK_TRACED;
132 ret = true;
133 }
134 spin_unlock_irq(&task->sighand->siglock);
135
136 return ret;
137}
138
139static void ptrace_unfreeze_traced(struct task_struct *task)
140{
141 if (task->state != __TASK_TRACED)
142 return;
143
144 WARN_ON(!task->ptrace || task->parent != current);
145
146 spin_lock_irq(&task->sighand->siglock);
147 if (__fatal_signal_pending(task))
148 wake_up_state(task, __TASK_TRACED);
149 else
150 task->state = TASK_TRACED;
151 spin_unlock_irq(&task->sighand->siglock);
152}
153
154
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157
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168
169
170
171static int ptrace_check_attach(struct task_struct *child, bool ignore_state)
172{
173 int ret = -ESRCH;
174
175
176
177
178
179
180
181
182 read_lock(&tasklist_lock);
183 if (child->ptrace && child->parent == current) {
184 WARN_ON(child->state == __TASK_TRACED);
185
186
187
188
189 if (ignore_state || ptrace_freeze_traced(child))
190 ret = 0;
191 }
192 read_unlock(&tasklist_lock);
193
194 if (!ret && !ignore_state) {
195 if (!wait_task_inactive(child, __TASK_TRACED)) {
196
197
198
199
200
201 WARN_ON(child->state == __TASK_TRACED);
202 ret = -ESRCH;
203 }
204 }
205
206 return ret;
207}
208
209static int ptrace_has_cap(struct user_namespace *ns, unsigned int mode)
210{
211 if (mode & PTRACE_MODE_NOAUDIT)
212 return has_ns_capability_noaudit(current, ns, CAP_SYS_PTRACE);
213 else
214 return has_ns_capability(current, ns, CAP_SYS_PTRACE);
215}
216
217
218static int __ptrace_may_access(struct task_struct *task, unsigned int mode)
219{
220 const struct cred *cred = current_cred(), *tcred;
221 int dumpable = 0;
222 kuid_t caller_uid;
223 kgid_t caller_gid;
224
225 if (!(mode & PTRACE_MODE_FSCREDS) == !(mode & PTRACE_MODE_REALCREDS)) {
226 WARN(1, "denying ptrace access check without PTRACE_MODE_*CREDS\n");
227 return -EPERM;
228 }
229
230
231
232
233
234
235
236
237
238
239
240 if (same_thread_group(task, current))
241 return 0;
242 rcu_read_lock();
243 if (mode & PTRACE_MODE_FSCREDS) {
244 caller_uid = cred->fsuid;
245 caller_gid = cred->fsgid;
246 } else {
247
248
249
250
251
252
253
254
255 caller_uid = cred->uid;
256 caller_gid = cred->gid;
257 }
258 tcred = __task_cred(task);
259 if (uid_eq(caller_uid, tcred->euid) &&
260 uid_eq(caller_uid, tcred->suid) &&
261 uid_eq(caller_uid, tcred->uid) &&
262 gid_eq(caller_gid, tcred->egid) &&
263 gid_eq(caller_gid, tcred->sgid) &&
264 gid_eq(caller_gid, tcred->gid))
265 goto ok;
266 if (ptrace_has_cap(tcred->user_ns, mode))
267 goto ok;
268 rcu_read_unlock();
269 return -EPERM;
270ok:
271 rcu_read_unlock();
272 smp_rmb();
273 if (task->mm)
274 dumpable = get_dumpable(task->mm);
275 rcu_read_lock();
276 if (dumpable != SUID_DUMP_USER &&
277 !ptrace_has_cap(__task_cred(task)->user_ns, mode)) {
278 rcu_read_unlock();
279 return -EPERM;
280 }
281 rcu_read_unlock();
282
283 return security_ptrace_access_check(task, mode);
284}
285
286bool ptrace_may_access(struct task_struct *task, unsigned int mode)
287{
288 int err;
289 task_lock(task);
290 err = __ptrace_may_access(task, mode);
291 task_unlock(task);
292 return !err;
293}
294
295static int ptrace_attach(struct task_struct *task, long request,
296 unsigned long addr,
297 unsigned long flags)
298{
299 bool seize = (request == PTRACE_SEIZE);
300 int retval;
301
302 retval = -EIO;
303 if (seize) {
304 if (addr != 0)
305 goto out;
306 if (flags & ~(unsigned long)PTRACE_O_MASK)
307 goto out;
308 flags = PT_PTRACED | PT_SEIZED | (flags << PT_OPT_FLAG_SHIFT);
309 } else {
310 flags = PT_PTRACED;
311 }
312
313 audit_ptrace(task);
314
315 retval = -EPERM;
316 if (unlikely(task->flags & PF_KTHREAD))
317 goto out;
318 if (same_thread_group(task, current))
319 goto out;
320
321
322
323
324
325
326 retval = -ERESTARTNOINTR;
327 if (mutex_lock_interruptible(&task->signal->cred_guard_mutex))
328 goto out;
329
330 task_lock(task);
331 retval = __ptrace_may_access(task, PTRACE_MODE_ATTACH_REALCREDS);
332 task_unlock(task);
333 if (retval)
334 goto unlock_creds;
335
336 write_lock_irq(&tasklist_lock);
337 retval = -EPERM;
338 if (unlikely(task->exit_state))
339 goto unlock_tasklist;
340 if (task->ptrace)
341 goto unlock_tasklist;
342
343 if (seize)
344 flags |= PT_SEIZED;
345 rcu_read_lock();
346 if (ns_capable(__task_cred(task)->user_ns, CAP_SYS_PTRACE))
347 flags |= PT_PTRACE_CAP;
348 rcu_read_unlock();
349 task->ptrace = flags;
350
351 __ptrace_link(task, current);
352
353
354 if (!seize)
355 send_sig_info(SIGSTOP, SEND_SIG_FORCED, task);
356
357 spin_lock(&task->sighand->siglock);
358
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374
375
376 if (task_is_stopped(task) &&
377 task_set_jobctl_pending(task, JOBCTL_TRAP_STOP | JOBCTL_TRAPPING))
378 signal_wake_up_state(task, __TASK_STOPPED);
379
380 spin_unlock(&task->sighand->siglock);
381
382 retval = 0;
383unlock_tasklist:
384 write_unlock_irq(&tasklist_lock);
385unlock_creds:
386 mutex_unlock(&task->signal->cred_guard_mutex);
387out:
388 if (!retval) {
389
390
391
392
393
394
395
396 wait_on_bit(&task->jobctl, JOBCTL_TRAPPING_BIT, TASK_KILLABLE);
397 proc_ptrace_connector(task, PTRACE_ATTACH);
398 }
399
400 return retval;
401}
402
403
404
405
406
407
408
409static int ptrace_traceme(void)
410{
411 int ret = -EPERM;
412
413 write_lock_irq(&tasklist_lock);
414
415 if (!current->ptrace) {
416 ret = security_ptrace_traceme(current->parent);
417
418
419
420
421
422 if (!ret && !(current->real_parent->flags & PF_EXITING)) {
423 current->ptrace = PT_PTRACED;
424 __ptrace_link(current, current->real_parent);
425 }
426 }
427 write_unlock_irq(&tasklist_lock);
428
429 return ret;
430}
431
432
433
434
435static int ignoring_children(struct sighand_struct *sigh)
436{
437 int ret;
438 spin_lock(&sigh->siglock);
439 ret = (sigh->action[SIGCHLD-1].sa.sa_handler == SIG_IGN) ||
440 (sigh->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT);
441 spin_unlock(&sigh->siglock);
442 return ret;
443}
444
445
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452
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455
456
457
458
459
460static bool __ptrace_detach(struct task_struct *tracer, struct task_struct *p)
461{
462 bool dead;
463
464 __ptrace_unlink(p);
465
466 if (p->exit_state != EXIT_ZOMBIE)
467 return false;
468
469 dead = !thread_group_leader(p);
470
471 if (!dead && thread_group_empty(p)) {
472 if (!same_thread_group(p->real_parent, tracer))
473 dead = do_notify_parent(p, p->exit_signal);
474 else if (ignoring_children(tracer->sighand)) {
475 __wake_up_parent(p, tracer);
476 dead = true;
477 }
478 }
479
480 if (dead)
481 p->exit_state = EXIT_DEAD;
482 return dead;
483}
484
485static int ptrace_detach(struct task_struct *child, unsigned int data)
486{
487 if (!valid_signal(data))
488 return -EIO;
489
490
491 ptrace_disable(child);
492 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
493
494 write_lock_irq(&tasklist_lock);
495
496
497
498
499 WARN_ON(!child->ptrace || child->exit_state);
500
501
502
503
504 child->exit_code = data;
505 __ptrace_detach(current, child);
506 write_unlock_irq(&tasklist_lock);
507
508 proc_ptrace_connector(child, PTRACE_DETACH);
509
510 return 0;
511}
512
513
514
515
516
517void exit_ptrace(struct task_struct *tracer, struct list_head *dead)
518{
519 struct task_struct *p, *n;
520
521 list_for_each_entry_safe(p, n, &tracer->ptraced, ptrace_entry) {
522 if (unlikely(p->ptrace & PT_EXITKILL))
523 send_sig_info(SIGKILL, SEND_SIG_FORCED, p);
524
525 if (__ptrace_detach(tracer, p))
526 list_add(&p->ptrace_entry, dead);
527 }
528}
529
530int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len)
531{
532 int copied = 0;
533
534 while (len > 0) {
535 char buf[128];
536 int this_len, retval;
537
538 this_len = (len > sizeof(buf)) ? sizeof(buf) : len;
539 retval = access_process_vm(tsk, src, buf, this_len, 0);
540 if (!retval) {
541 if (copied)
542 break;
543 return -EIO;
544 }
545 if (copy_to_user(dst, buf, retval))
546 return -EFAULT;
547 copied += retval;
548 src += retval;
549 dst += retval;
550 len -= retval;
551 }
552 return copied;
553}
554
555int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len)
556{
557 int copied = 0;
558
559 while (len > 0) {
560 char buf[128];
561 int this_len, retval;
562
563 this_len = (len > sizeof(buf)) ? sizeof(buf) : len;
564 if (copy_from_user(buf, src, this_len))
565 return -EFAULT;
566 retval = access_process_vm(tsk, dst, buf, this_len, 1);
567 if (!retval) {
568 if (copied)
569 break;
570 return -EIO;
571 }
572 copied += retval;
573 src += retval;
574 dst += retval;
575 len -= retval;
576 }
577 return copied;
578}
579
580static int ptrace_setoptions(struct task_struct *child, unsigned long data)
581{
582 unsigned flags;
583
584 if (data & ~(unsigned long)PTRACE_O_MASK)
585 return -EINVAL;
586
587 if (unlikely(data & PTRACE_O_SUSPEND_SECCOMP)) {
588 if (!config_enabled(CONFIG_CHECKPOINT_RESTORE) ||
589 !config_enabled(CONFIG_SECCOMP))
590 return -EINVAL;
591
592 if (!capable(CAP_SYS_ADMIN))
593 return -EPERM;
594
595 if (seccomp_mode(¤t->seccomp) != SECCOMP_MODE_DISABLED ||
596 current->ptrace & PT_SUSPEND_SECCOMP)
597 return -EPERM;
598 }
599
600
601 flags = child->ptrace;
602 flags &= ~(PTRACE_O_MASK << PT_OPT_FLAG_SHIFT);
603 flags |= (data << PT_OPT_FLAG_SHIFT);
604 child->ptrace = flags;
605
606 return 0;
607}
608
609static int ptrace_getsiginfo(struct task_struct *child, siginfo_t *info)
610{
611 unsigned long flags;
612 int error = -ESRCH;
613
614 if (lock_task_sighand(child, &flags)) {
615 error = -EINVAL;
616 if (likely(child->last_siginfo != NULL)) {
617 *info = *child->last_siginfo;
618 error = 0;
619 }
620 unlock_task_sighand(child, &flags);
621 }
622 return error;
623}
624
625static int ptrace_setsiginfo(struct task_struct *child, const siginfo_t *info)
626{
627 unsigned long flags;
628 int error = -ESRCH;
629
630 if (lock_task_sighand(child, &flags)) {
631 error = -EINVAL;
632 if (likely(child->last_siginfo != NULL)) {
633 *child->last_siginfo = *info;
634 error = 0;
635 }
636 unlock_task_sighand(child, &flags);
637 }
638 return error;
639}
640
641static int ptrace_peek_siginfo(struct task_struct *child,
642 unsigned long addr,
643 unsigned long data)
644{
645 struct ptrace_peeksiginfo_args arg;
646 struct sigpending *pending;
647 struct sigqueue *q;
648 int ret, i;
649
650 ret = copy_from_user(&arg, (void __user *) addr,
651 sizeof(struct ptrace_peeksiginfo_args));
652 if (ret)
653 return -EFAULT;
654
655 if (arg.flags & ~PTRACE_PEEKSIGINFO_SHARED)
656 return -EINVAL;
657
658 if (arg.nr < 0)
659 return -EINVAL;
660
661 if (arg.flags & PTRACE_PEEKSIGINFO_SHARED)
662 pending = &child->signal->shared_pending;
663 else
664 pending = &child->pending;
665
666 for (i = 0; i < arg.nr; ) {
667 siginfo_t info;
668 s32 off = arg.off + i;
669
670 spin_lock_irq(&child->sighand->siglock);
671 list_for_each_entry(q, &pending->list, list) {
672 if (!off--) {
673 copy_siginfo(&info, &q->info);
674 break;
675 }
676 }
677 spin_unlock_irq(&child->sighand->siglock);
678
679 if (off >= 0)
680 break;
681
682#ifdef CONFIG_COMPAT
683 if (unlikely(in_compat_syscall())) {
684 compat_siginfo_t __user *uinfo = compat_ptr(data);
685
686 if (copy_siginfo_to_user32(uinfo, &info) ||
687 __put_user(info.si_code, &uinfo->si_code)) {
688 ret = -EFAULT;
689 break;
690 }
691
692 } else
693#endif
694 {
695 siginfo_t __user *uinfo = (siginfo_t __user *) data;
696
697 if (copy_siginfo_to_user(uinfo, &info) ||
698 __put_user(info.si_code, &uinfo->si_code)) {
699 ret = -EFAULT;
700 break;
701 }
702 }
703
704 data += sizeof(siginfo_t);
705 i++;
706
707 if (signal_pending(current))
708 break;
709
710 cond_resched();
711 }
712
713 if (i > 0)
714 return i;
715
716 return ret;
717}
718
719#ifdef PTRACE_SINGLESTEP
720#define is_singlestep(request) ((request) == PTRACE_SINGLESTEP)
721#else
722#define is_singlestep(request) 0
723#endif
724
725#ifdef PTRACE_SINGLEBLOCK
726#define is_singleblock(request) ((request) == PTRACE_SINGLEBLOCK)
727#else
728#define is_singleblock(request) 0
729#endif
730
731#ifdef PTRACE_SYSEMU
732#define is_sysemu_singlestep(request) ((request) == PTRACE_SYSEMU_SINGLESTEP)
733#else
734#define is_sysemu_singlestep(request) 0
735#endif
736
737static int ptrace_resume(struct task_struct *child, long request,
738 unsigned long data)
739{
740 bool need_siglock;
741
742 if (!valid_signal(data))
743 return -EIO;
744
745 if (request == PTRACE_SYSCALL)
746 set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
747 else
748 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
749
750#ifdef TIF_SYSCALL_EMU
751 if (request == PTRACE_SYSEMU || request == PTRACE_SYSEMU_SINGLESTEP)
752 set_tsk_thread_flag(child, TIF_SYSCALL_EMU);
753 else
754 clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
755#endif
756
757 if (is_singleblock(request)) {
758 if (unlikely(!arch_has_block_step()))
759 return -EIO;
760 user_enable_block_step(child);
761 } else if (is_singlestep(request) || is_sysemu_singlestep(request)) {
762 if (unlikely(!arch_has_single_step()))
763 return -EIO;
764 user_enable_single_step(child);
765 } else {
766 user_disable_single_step(child);
767 }
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782 need_siglock = data && !thread_group_empty(current);
783 if (need_siglock)
784 spin_lock_irq(&child->sighand->siglock);
785 child->exit_code = data;
786 wake_up_state(child, __TASK_TRACED);
787 if (need_siglock)
788 spin_unlock_irq(&child->sighand->siglock);
789
790 return 0;
791}
792
793#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
794
795static const struct user_regset *
796find_regset(const struct user_regset_view *view, unsigned int type)
797{
798 const struct user_regset *regset;
799 int n;
800
801 for (n = 0; n < view->n; ++n) {
802 regset = view->regsets + n;
803 if (regset->core_note_type == type)
804 return regset;
805 }
806
807 return NULL;
808}
809
810static int ptrace_regset(struct task_struct *task, int req, unsigned int type,
811 struct iovec *kiov)
812{
813 const struct user_regset_view *view = task_user_regset_view(task);
814 const struct user_regset *regset = find_regset(view, type);
815 int regset_no;
816
817 if (!regset || (kiov->iov_len % regset->size) != 0)
818 return -EINVAL;
819
820 regset_no = regset - view->regsets;
821 kiov->iov_len = min(kiov->iov_len,
822 (__kernel_size_t) (regset->n * regset->size));
823
824 if (req == PTRACE_GETREGSET)
825 return copy_regset_to_user(task, view, regset_no, 0,
826 kiov->iov_len, kiov->iov_base);
827 else
828 return copy_regset_from_user(task, view, regset_no, 0,
829 kiov->iov_len, kiov->iov_base);
830}
831
832
833
834
835
836
837EXPORT_SYMBOL_GPL(task_user_regset_view);
838#endif
839
840int ptrace_request(struct task_struct *child, long request,
841 unsigned long addr, unsigned long data)
842{
843 bool seized = child->ptrace & PT_SEIZED;
844 int ret = -EIO;
845 siginfo_t siginfo, *si;
846 void __user *datavp = (void __user *) data;
847 unsigned long __user *datalp = datavp;
848 unsigned long flags;
849
850 switch (request) {
851 case PTRACE_PEEKTEXT:
852 case PTRACE_PEEKDATA:
853 return generic_ptrace_peekdata(child, addr, data);
854 case PTRACE_POKETEXT:
855 case PTRACE_POKEDATA:
856 return generic_ptrace_pokedata(child, addr, data);
857
858#ifdef PTRACE_OLDSETOPTIONS
859 case PTRACE_OLDSETOPTIONS:
860#endif
861 case PTRACE_SETOPTIONS:
862 ret = ptrace_setoptions(child, data);
863 break;
864 case PTRACE_GETEVENTMSG:
865 ret = put_user(child->ptrace_message, datalp);
866 break;
867
868 case PTRACE_PEEKSIGINFO:
869 ret = ptrace_peek_siginfo(child, addr, data);
870 break;
871
872 case PTRACE_GETSIGINFO:
873 ret = ptrace_getsiginfo(child, &siginfo);
874 if (!ret)
875 ret = copy_siginfo_to_user(datavp, &siginfo);
876 break;
877
878 case PTRACE_SETSIGINFO:
879 if (copy_from_user(&siginfo, datavp, sizeof siginfo))
880 ret = -EFAULT;
881 else
882 ret = ptrace_setsiginfo(child, &siginfo);
883 break;
884
885 case PTRACE_GETSIGMASK:
886 if (addr != sizeof(sigset_t)) {
887 ret = -EINVAL;
888 break;
889 }
890
891 if (copy_to_user(datavp, &child->blocked, sizeof(sigset_t)))
892 ret = -EFAULT;
893 else
894 ret = 0;
895
896 break;
897
898 case PTRACE_SETSIGMASK: {
899 sigset_t new_set;
900
901 if (addr != sizeof(sigset_t)) {
902 ret = -EINVAL;
903 break;
904 }
905
906 if (copy_from_user(&new_set, datavp, sizeof(sigset_t))) {
907 ret = -EFAULT;
908 break;
909 }
910
911 sigdelsetmask(&new_set, sigmask(SIGKILL)|sigmask(SIGSTOP));
912
913
914
915
916
917
918 spin_lock_irq(&child->sighand->siglock);
919 child->blocked = new_set;
920 spin_unlock_irq(&child->sighand->siglock);
921
922 ret = 0;
923 break;
924 }
925
926 case PTRACE_INTERRUPT:
927
928
929
930
931
932
933
934
935
936
937 if (unlikely(!seized || !lock_task_sighand(child, &flags)))
938 break;
939
940
941
942
943
944
945
946 if (likely(task_set_jobctl_pending(child, JOBCTL_TRAP_STOP)))
947 ptrace_signal_wake_up(child, child->jobctl & JOBCTL_LISTENING);
948
949 unlock_task_sighand(child, &flags);
950 ret = 0;
951 break;
952
953 case PTRACE_LISTEN:
954
955
956
957
958
959
960
961
962 if (unlikely(!seized || !lock_task_sighand(child, &flags)))
963 break;
964
965 si = child->last_siginfo;
966 if (likely(si && (si->si_code >> 8) == PTRACE_EVENT_STOP)) {
967 child->jobctl |= JOBCTL_LISTENING;
968
969
970
971
972 if (child->jobctl & JOBCTL_TRAP_NOTIFY)
973 ptrace_signal_wake_up(child, true);
974 ret = 0;
975 }
976 unlock_task_sighand(child, &flags);
977 break;
978
979 case PTRACE_DETACH:
980 ret = ptrace_detach(child, data);
981 break;
982
983#ifdef CONFIG_BINFMT_ELF_FDPIC
984 case PTRACE_GETFDPIC: {
985 struct mm_struct *mm = get_task_mm(child);
986 unsigned long tmp = 0;
987
988 ret = -ESRCH;
989 if (!mm)
990 break;
991
992 switch (addr) {
993 case PTRACE_GETFDPIC_EXEC:
994 tmp = mm->context.exec_fdpic_loadmap;
995 break;
996 case PTRACE_GETFDPIC_INTERP:
997 tmp = mm->context.interp_fdpic_loadmap;
998 break;
999 default:
1000 break;
1001 }
1002 mmput(mm);
1003
1004 ret = put_user(tmp, datalp);
1005 break;
1006 }
1007#endif
1008
1009#ifdef PTRACE_SINGLESTEP
1010 case PTRACE_SINGLESTEP:
1011#endif
1012#ifdef PTRACE_SINGLEBLOCK
1013 case PTRACE_SINGLEBLOCK:
1014#endif
1015#ifdef PTRACE_SYSEMU
1016 case PTRACE_SYSEMU:
1017 case PTRACE_SYSEMU_SINGLESTEP:
1018#endif
1019 case PTRACE_SYSCALL:
1020 case PTRACE_CONT:
1021 return ptrace_resume(child, request, data);
1022
1023 case PTRACE_KILL:
1024 if (child->exit_state)
1025 return 0;
1026 return ptrace_resume(child, request, SIGKILL);
1027
1028#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
1029 case PTRACE_GETREGSET:
1030 case PTRACE_SETREGSET: {
1031 struct iovec kiov;
1032 struct iovec __user *uiov = datavp;
1033
1034 if (!access_ok(VERIFY_WRITE, uiov, sizeof(*uiov)))
1035 return -EFAULT;
1036
1037 if (__get_user(kiov.iov_base, &uiov->iov_base) ||
1038 __get_user(kiov.iov_len, &uiov->iov_len))
1039 return -EFAULT;
1040
1041 ret = ptrace_regset(child, request, addr, &kiov);
1042 if (!ret)
1043 ret = __put_user(kiov.iov_len, &uiov->iov_len);
1044 break;
1045 }
1046#endif
1047
1048 case PTRACE_SECCOMP_GET_FILTER:
1049 ret = seccomp_get_filter(child, addr, datavp);
1050 break;
1051
1052 default:
1053 break;
1054 }
1055
1056 return ret;
1057}
1058
1059static struct task_struct *ptrace_get_task_struct(pid_t pid)
1060{
1061 struct task_struct *child;
1062
1063 rcu_read_lock();
1064 child = find_task_by_vpid(pid);
1065 if (child)
1066 get_task_struct(child);
1067 rcu_read_unlock();
1068
1069 if (!child)
1070 return ERR_PTR(-ESRCH);
1071 return child;
1072}
1073
1074#ifndef arch_ptrace_attach
1075#define arch_ptrace_attach(child) do { } while (0)
1076#endif
1077
1078SYSCALL_DEFINE4(ptrace, long, request, long, pid, unsigned long, addr,
1079 unsigned long, data)
1080{
1081 struct task_struct *child;
1082 long ret;
1083
1084 if (request == PTRACE_TRACEME) {
1085 ret = ptrace_traceme();
1086 if (!ret)
1087 arch_ptrace_attach(current);
1088 goto out;
1089 }
1090
1091 child = ptrace_get_task_struct(pid);
1092 if (IS_ERR(child)) {
1093 ret = PTR_ERR(child);
1094 goto out;
1095 }
1096
1097 if (request == PTRACE_ATTACH || request == PTRACE_SEIZE) {
1098 ret = ptrace_attach(child, request, addr, data);
1099
1100
1101
1102
1103 if (!ret)
1104 arch_ptrace_attach(child);
1105 goto out_put_task_struct;
1106 }
1107
1108 ret = ptrace_check_attach(child, request == PTRACE_KILL ||
1109 request == PTRACE_INTERRUPT);
1110 if (ret < 0)
1111 goto out_put_task_struct;
1112
1113 ret = arch_ptrace(child, request, addr, data);
1114 if (ret || request != PTRACE_DETACH)
1115 ptrace_unfreeze_traced(child);
1116
1117 out_put_task_struct:
1118 put_task_struct(child);
1119 out:
1120 return ret;
1121}
1122
1123int generic_ptrace_peekdata(struct task_struct *tsk, unsigned long addr,
1124 unsigned long data)
1125{
1126 unsigned long tmp;
1127 int copied;
1128
1129 copied = access_process_vm(tsk, addr, &tmp, sizeof(tmp), 0);
1130 if (copied != sizeof(tmp))
1131 return -EIO;
1132 return put_user(tmp, (unsigned long __user *)data);
1133}
1134
1135int generic_ptrace_pokedata(struct task_struct *tsk, unsigned long addr,
1136 unsigned long data)
1137{
1138 int copied;
1139
1140 copied = access_process_vm(tsk, addr, &data, sizeof(data), 1);
1141 return (copied == sizeof(data)) ? 0 : -EIO;
1142}
1143
1144#if defined CONFIG_COMPAT
1145
1146int compat_ptrace_request(struct task_struct *child, compat_long_t request,
1147 compat_ulong_t addr, compat_ulong_t data)
1148{
1149 compat_ulong_t __user *datap = compat_ptr(data);
1150 compat_ulong_t word;
1151 siginfo_t siginfo;
1152 int ret;
1153
1154 switch (request) {
1155 case PTRACE_PEEKTEXT:
1156 case PTRACE_PEEKDATA:
1157 ret = access_process_vm(child, addr, &word, sizeof(word), 0);
1158 if (ret != sizeof(word))
1159 ret = -EIO;
1160 else
1161 ret = put_user(word, datap);
1162 break;
1163
1164 case PTRACE_POKETEXT:
1165 case PTRACE_POKEDATA:
1166 ret = access_process_vm(child, addr, &data, sizeof(data), 1);
1167 ret = (ret != sizeof(data) ? -EIO : 0);
1168 break;
1169
1170 case PTRACE_GETEVENTMSG:
1171 ret = put_user((compat_ulong_t) child->ptrace_message, datap);
1172 break;
1173
1174 case PTRACE_GETSIGINFO:
1175 ret = ptrace_getsiginfo(child, &siginfo);
1176 if (!ret)
1177 ret = copy_siginfo_to_user32(
1178 (struct compat_siginfo __user *) datap,
1179 &siginfo);
1180 break;
1181
1182 case PTRACE_SETSIGINFO:
1183 memset(&siginfo, 0, sizeof siginfo);
1184 if (copy_siginfo_from_user32(
1185 &siginfo, (struct compat_siginfo __user *) datap))
1186 ret = -EFAULT;
1187 else
1188 ret = ptrace_setsiginfo(child, &siginfo);
1189 break;
1190#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
1191 case PTRACE_GETREGSET:
1192 case PTRACE_SETREGSET:
1193 {
1194 struct iovec kiov;
1195 struct compat_iovec __user *uiov =
1196 (struct compat_iovec __user *) datap;
1197 compat_uptr_t ptr;
1198 compat_size_t len;
1199
1200 if (!access_ok(VERIFY_WRITE, uiov, sizeof(*uiov)))
1201 return -EFAULT;
1202
1203 if (__get_user(ptr, &uiov->iov_base) ||
1204 __get_user(len, &uiov->iov_len))
1205 return -EFAULT;
1206
1207 kiov.iov_base = compat_ptr(ptr);
1208 kiov.iov_len = len;
1209
1210 ret = ptrace_regset(child, request, addr, &kiov);
1211 if (!ret)
1212 ret = __put_user(kiov.iov_len, &uiov->iov_len);
1213 break;
1214 }
1215#endif
1216
1217 default:
1218 ret = ptrace_request(child, request, addr, data);
1219 }
1220
1221 return ret;
1222}
1223
1224COMPAT_SYSCALL_DEFINE4(ptrace, compat_long_t, request, compat_long_t, pid,
1225 compat_long_t, addr, compat_long_t, data)
1226{
1227 struct task_struct *child;
1228 long ret;
1229
1230 if (request == PTRACE_TRACEME) {
1231 ret = ptrace_traceme();
1232 goto out;
1233 }
1234
1235 child = ptrace_get_task_struct(pid);
1236 if (IS_ERR(child)) {
1237 ret = PTR_ERR(child);
1238 goto out;
1239 }
1240
1241 if (request == PTRACE_ATTACH || request == PTRACE_SEIZE) {
1242 ret = ptrace_attach(child, request, addr, data);
1243
1244
1245
1246
1247 if (!ret)
1248 arch_ptrace_attach(child);
1249 goto out_put_task_struct;
1250 }
1251
1252 ret = ptrace_check_attach(child, request == PTRACE_KILL ||
1253 request == PTRACE_INTERRUPT);
1254 if (!ret) {
1255 ret = compat_arch_ptrace(child, request, addr, data);
1256 if (ret || request != PTRACE_DETACH)
1257 ptrace_unfreeze_traced(child);
1258 }
1259
1260 out_put_task_struct:
1261 put_task_struct(child);
1262 out:
1263 return ret;
1264}
1265#endif
1266