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