2 * linux/kernel/ptrace.c
4 * (C) Copyright 1999 Linus Torvalds
6 * Common interfaces for "ptrace()" which we do not want
7 * to continually duplicate across every architecture.
10 #include <linux/capability.h>
11 #include <linux/export.h>
12 #include <linux/sched.h>
13 #include <linux/errno.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/audit.h>
21 #include <linux/pid_namespace.h>
22 #include <linux/syscalls.h>
23 #include <linux/uaccess.h>
24 #include <linux/regset.h>
25 #include <linux/hw_breakpoint.h>
26 #include <linux/cn_proc.h>
27 #include <linux/uio.h>
30 static int ptrace_trapping_sleep_fn(void *flags)
37 * ptrace a task: make the debugger its new parent and
38 * move it to the ptrace list.
40 * Must be called with the tasklist lock write-held.
42 void __ptrace_link(struct task_struct *child, struct task_struct *new_parent)
44 BUG_ON(!list_empty(&child->ptrace_entry));
45 list_add(&child->ptrace_entry, &new_parent->ptraced);
46 child->parent = new_parent;
50 * __ptrace_unlink - unlink ptracee and restore its execution state
51 * @child: ptracee to be unlinked
53 * Remove @child from the ptrace list, move it back to the original parent,
54 * and restore the execution state so that it conforms to the group stop
57 * Unlinking can happen via two paths - explicit PTRACE_DETACH or ptracer
58 * exiting. For PTRACE_DETACH, unless the ptracee has been killed between
59 * ptrace_check_attach() and here, it's guaranteed to be in TASK_TRACED.
60 * If the ptracer is exiting, the ptracee can be in any state.
62 * After detach, the ptracee should be in a state which conforms to the
63 * group stop. If the group is stopped or in the process of stopping, the
64 * ptracee should be put into TASK_STOPPED; otherwise, it should be woken
65 * up from TASK_TRACED.
67 * If the ptracee is in TASK_TRACED and needs to be moved to TASK_STOPPED,
68 * it goes through TRACED -> RUNNING -> STOPPED transition which is similar
69 * to but in the opposite direction of what happens while attaching to a
70 * stopped task. However, in this direction, the intermediate RUNNING
71 * state is not hidden even from the current ptracer and if it immediately
72 * re-attaches and performs a WNOHANG wait(2), it may fail.
75 * write_lock_irq(tasklist_lock)
77 void __ptrace_unlink(struct task_struct *child)
79 BUG_ON(!child->ptrace);
82 child->parent = child->real_parent;
83 list_del_init(&child->ptrace_entry);
85 spin_lock(&child->sighand->siglock);
88 * Clear all pending traps and TRAPPING. TRAPPING should be
89 * cleared regardless of JOBCTL_STOP_PENDING. Do it explicitly.
91 task_clear_jobctl_pending(child, JOBCTL_TRAP_MASK);
92 task_clear_jobctl_trapping(child);
95 * Reinstate JOBCTL_STOP_PENDING if group stop is in effect and
98 if (!(child->flags & PF_EXITING) &&
99 (child->signal->flags & SIGNAL_STOP_STOPPED ||
100 child->signal->group_stop_count)) {
101 child->jobctl |= JOBCTL_STOP_PENDING;
104 * This is only possible if this thread was cloned by the
105 * traced task running in the stopped group, set the signal
106 * for the future reports.
107 * FIXME: we should change ptrace_init_task() to handle this
110 if (!(child->jobctl & JOBCTL_STOP_SIGMASK))
111 child->jobctl |= SIGSTOP;
115 * If transition to TASK_STOPPED is pending or in TASK_TRACED, kick
116 * @child in the butt. Note that @resume should be used iff @child
117 * is in TASK_TRACED; otherwise, we might unduly disrupt
118 * TASK_KILLABLE sleeps.
120 if (child->jobctl & JOBCTL_STOP_PENDING || task_is_traced(child))
121 ptrace_signal_wake_up(child, true);
123 spin_unlock(&child->sighand->siglock);
126 /* Ensure that nothing can wake it up, even SIGKILL */
127 static bool ptrace_freeze_traced(struct task_struct *task)
131 /* Lockless, nobody but us can set this flag */
132 if (task->jobctl & JOBCTL_LISTENING)
135 spin_lock_irq(&task->sighand->siglock);
136 if (task_is_traced(task) && !__fatal_signal_pending(task)) {
137 task->state = __TASK_TRACED;
140 spin_unlock_irq(&task->sighand->siglock);
145 static void ptrace_unfreeze_traced(struct task_struct *task)
147 if (task->state != __TASK_TRACED)
150 WARN_ON(!task->ptrace || task->parent != current);
152 spin_lock_irq(&task->sighand->siglock);
153 if (__fatal_signal_pending(task))
154 wake_up_state(task, __TASK_TRACED);
156 task->state = TASK_TRACED;
157 spin_unlock_irq(&task->sighand->siglock);
161 * ptrace_check_attach - check whether ptracee is ready for ptrace operation
162 * @child: ptracee to check for
163 * @ignore_state: don't check whether @child is currently %TASK_TRACED
165 * Check whether @child is being ptraced by %current and ready for further
166 * ptrace operations. If @ignore_state is %false, @child also should be in
167 * %TASK_TRACED state and on return the child is guaranteed to be traced
168 * and not executing. If @ignore_state is %true, @child can be in any
172 * Grabs and releases tasklist_lock and @child->sighand->siglock.
175 * 0 on success, -ESRCH if %child is not ready.
177 static int ptrace_check_attach(struct task_struct *child, bool ignore_state)
182 * We take the read lock around doing both checks to close a
183 * possible race where someone else was tracing our child and
184 * detached between these two checks. After this locked check,
185 * we are sure that this is our traced child and that can only
186 * be changed by us so it's not changing right after this.
188 read_lock(&tasklist_lock);
189 if (child->ptrace && child->parent == current) {
190 WARN_ON(child->state == __TASK_TRACED);
192 * child->sighand can't be NULL, release_task()
193 * does ptrace_unlink() before __exit_signal().
195 if (ignore_state || ptrace_freeze_traced(child))
198 read_unlock(&tasklist_lock);
200 if (!ret && !ignore_state) {
201 if (!wait_task_inactive(child, __TASK_TRACED)) {
203 * This can only happen if may_ptrace_stop() fails and
204 * ptrace_stop() changes ->state back to TASK_RUNNING,
205 * so we should not worry about leaking __TASK_TRACED.
207 WARN_ON(child->state == __TASK_TRACED);
215 static int ptrace_has_cap(struct user_namespace *ns, unsigned int mode)
217 if (mode & PTRACE_MODE_NOAUDIT)
218 return has_ns_capability_noaudit(current, ns, CAP_SYS_PTRACE);
220 return has_ns_capability(current, ns, CAP_SYS_PTRACE);
223 /* Returns 0 on success, -errno on denial. */
224 static int __ptrace_may_access(struct task_struct *task, unsigned int mode)
226 const struct cred *cred = current_cred(), *tcred;
228 /* May we inspect the given task?
229 * This check is used both for attaching with ptrace
230 * and for allowing access to sensitive information in /proc.
232 * ptrace_attach denies several cases that /proc allows
233 * because setting up the necessary parent/child relationship
234 * or halting the specified task is impossible.
237 /* Don't let security modules deny introspection */
241 tcred = __task_cred(task);
242 if (uid_eq(cred->uid, tcred->euid) &&
243 uid_eq(cred->uid, tcred->suid) &&
244 uid_eq(cred->uid, tcred->uid) &&
245 gid_eq(cred->gid, tcred->egid) &&
246 gid_eq(cred->gid, tcred->sgid) &&
247 gid_eq(cred->gid, tcred->gid))
249 if (ptrace_has_cap(tcred->user_ns, mode))
257 dumpable = get_dumpable(task->mm);
259 if (!dumpable && !ptrace_has_cap(__task_cred(task)->user_ns, mode)) {
265 return security_ptrace_access_check(task, mode);
268 bool ptrace_may_access(struct task_struct *task, unsigned int mode)
272 err = __ptrace_may_access(task, mode);
277 static int ptrace_attach(struct task_struct *task, long request,
281 bool seize = (request == PTRACE_SEIZE);
288 if (flags & ~(unsigned long)PTRACE_O_MASK)
290 flags = PT_PTRACED | PT_SEIZED | (flags << PT_OPT_FLAG_SHIFT);
298 if (unlikely(task->flags & PF_KTHREAD))
300 if (same_thread_group(task, current))
304 * Protect exec's credential calculations against our interference;
305 * SUID, SGID and LSM creds get determined differently
308 retval = -ERESTARTNOINTR;
309 if (mutex_lock_interruptible(&task->signal->cred_guard_mutex))
313 retval = __ptrace_may_access(task, PTRACE_MODE_ATTACH);
318 write_lock_irq(&tasklist_lock);
320 if (unlikely(task->exit_state))
321 goto unlock_tasklist;
323 goto unlock_tasklist;
328 if (ns_capable(__task_cred(task)->user_ns, CAP_SYS_PTRACE))
329 flags |= PT_PTRACE_CAP;
331 task->ptrace = flags;
333 __ptrace_link(task, current);
335 /* SEIZE doesn't trap tracee on attach */
337 send_sig_info(SIGSTOP, SEND_SIG_FORCED, task);
339 spin_lock(&task->sighand->siglock);
342 * If the task is already STOPPED, set JOBCTL_TRAP_STOP and
343 * TRAPPING, and kick it so that it transits to TRACED. TRAPPING
344 * will be cleared if the child completes the transition or any
345 * event which clears the group stop states happens. We'll wait
346 * for the transition to complete before returning from this
349 * This hides STOPPED -> RUNNING -> TRACED transition from the
350 * attaching thread but a different thread in the same group can
351 * still observe the transient RUNNING state. IOW, if another
352 * thread's WNOHANG wait(2) on the stopped tracee races against
353 * ATTACH, the wait(2) may fail due to the transient RUNNING.
355 * The following task_is_stopped() test is safe as both transitions
356 * in and out of STOPPED are protected by siglock.
358 if (task_is_stopped(task) &&
359 task_set_jobctl_pending(task, JOBCTL_TRAP_STOP | JOBCTL_TRAPPING))
360 signal_wake_up_state(task, __TASK_STOPPED);
362 spin_unlock(&task->sighand->siglock);
366 write_unlock_irq(&tasklist_lock);
368 mutex_unlock(&task->signal->cred_guard_mutex);
371 wait_on_bit(&task->jobctl, JOBCTL_TRAPPING_BIT,
372 ptrace_trapping_sleep_fn, TASK_UNINTERRUPTIBLE);
373 proc_ptrace_connector(task, PTRACE_ATTACH);
380 * ptrace_traceme -- helper for PTRACE_TRACEME
382 * Performs checks and sets PT_PTRACED.
383 * Should be used by all ptrace implementations for PTRACE_TRACEME.
385 static int ptrace_traceme(void)
389 write_lock_irq(&tasklist_lock);
390 /* Are we already being traced? */
391 if (!current->ptrace) {
392 ret = security_ptrace_traceme(current->parent);
394 * Check PF_EXITING to ensure ->real_parent has not passed
395 * exit_ptrace(). Otherwise we don't report the error but
396 * pretend ->real_parent untraces us right after return.
398 if (!ret && !(current->real_parent->flags & PF_EXITING)) {
399 current->ptrace = PT_PTRACED;
400 __ptrace_link(current, current->real_parent);
403 write_unlock_irq(&tasklist_lock);
409 * Called with irqs disabled, returns true if childs should reap themselves.
411 static int ignoring_children(struct sighand_struct *sigh)
414 spin_lock(&sigh->siglock);
415 ret = (sigh->action[SIGCHLD-1].sa.sa_handler == SIG_IGN) ||
416 (sigh->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT);
417 spin_unlock(&sigh->siglock);
422 * Called with tasklist_lock held for writing.
423 * Unlink a traced task, and clean it up if it was a traced zombie.
424 * Return true if it needs to be reaped with release_task().
425 * (We can't call release_task() here because we already hold tasklist_lock.)
427 * If it's a zombie, our attachedness prevented normal parent notification
428 * or self-reaping. Do notification now if it would have happened earlier.
429 * If it should reap itself, return true.
431 * If it's our own child, there is no notification to do. But if our normal
432 * children self-reap, then this child was prevented by ptrace and we must
433 * reap it now, in that case we must also wake up sub-threads sleeping in
436 static bool __ptrace_detach(struct task_struct *tracer, struct task_struct *p)
442 if (p->exit_state != EXIT_ZOMBIE)
445 dead = !thread_group_leader(p);
447 if (!dead && thread_group_empty(p)) {
448 if (!same_thread_group(p->real_parent, tracer))
449 dead = do_notify_parent(p, p->exit_signal);
450 else if (ignoring_children(tracer->sighand)) {
451 __wake_up_parent(p, tracer);
455 /* Mark it as in the process of being reaped. */
457 p->exit_state = EXIT_DEAD;
461 static int ptrace_detach(struct task_struct *child, unsigned int data)
465 if (!valid_signal(data))
468 /* Architecture-specific hardware disable .. */
469 ptrace_disable(child);
470 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
472 write_lock_irq(&tasklist_lock);
474 * This child can be already killed. Make sure de_thread() or
475 * our sub-thread doing do_wait() didn't do release_task() yet.
478 child->exit_code = data;
479 dead = __ptrace_detach(current, child);
481 write_unlock_irq(&tasklist_lock);
483 proc_ptrace_connector(child, PTRACE_DETACH);
491 * Detach all tasks we were using ptrace on. Called with tasklist held
492 * for writing, and returns with it held too. But note it can release
493 * and reacquire the lock.
495 void exit_ptrace(struct task_struct *tracer)
496 __releases(&tasklist_lock)
497 __acquires(&tasklist_lock)
499 struct task_struct *p, *n;
500 LIST_HEAD(ptrace_dead);
502 if (likely(list_empty(&tracer->ptraced)))
505 list_for_each_entry_safe(p, n, &tracer->ptraced, ptrace_entry) {
506 if (unlikely(p->ptrace & PT_EXITKILL))
507 send_sig_info(SIGKILL, SEND_SIG_FORCED, p);
509 if (__ptrace_detach(tracer, p))
510 list_add(&p->ptrace_entry, &ptrace_dead);
513 write_unlock_irq(&tasklist_lock);
514 BUG_ON(!list_empty(&tracer->ptraced));
516 list_for_each_entry_safe(p, n, &ptrace_dead, ptrace_entry) {
517 list_del_init(&p->ptrace_entry);
521 write_lock_irq(&tasklist_lock);
524 int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len)
530 int this_len, retval;
532 this_len = (len > sizeof(buf)) ? sizeof(buf) : len;
533 retval = access_process_vm(tsk, src, buf, this_len, 0);
539 if (copy_to_user(dst, buf, retval))
549 int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len)
555 int this_len, retval;
557 this_len = (len > sizeof(buf)) ? sizeof(buf) : len;
558 if (copy_from_user(buf, src, this_len))
560 retval = access_process_vm(tsk, dst, buf, this_len, 1);
574 static int ptrace_setoptions(struct task_struct *child, unsigned long data)
578 if (data & ~(unsigned long)PTRACE_O_MASK)
581 /* Avoid intermediate state when all opts are cleared */
582 flags = child->ptrace;
583 flags &= ~(PTRACE_O_MASK << PT_OPT_FLAG_SHIFT);
584 flags |= (data << PT_OPT_FLAG_SHIFT);
585 child->ptrace = flags;
590 static int ptrace_getsiginfo(struct task_struct *child, siginfo_t *info)
595 if (lock_task_sighand(child, &flags)) {
597 if (likely(child->last_siginfo != NULL)) {
598 *info = *child->last_siginfo;
601 unlock_task_sighand(child, &flags);
606 static int ptrace_setsiginfo(struct task_struct *child, const siginfo_t *info)
611 if (lock_task_sighand(child, &flags)) {
613 if (likely(child->last_siginfo != NULL)) {
614 *child->last_siginfo = *info;
617 unlock_task_sighand(child, &flags);
623 #ifdef PTRACE_SINGLESTEP
624 #define is_singlestep(request) ((request) == PTRACE_SINGLESTEP)
626 #define is_singlestep(request) 0
629 #ifdef PTRACE_SINGLEBLOCK
630 #define is_singleblock(request) ((request) == PTRACE_SINGLEBLOCK)
632 #define is_singleblock(request) 0
636 #define is_sysemu_singlestep(request) ((request) == PTRACE_SYSEMU_SINGLESTEP)
638 #define is_sysemu_singlestep(request) 0
641 static int ptrace_resume(struct task_struct *child, long request,
644 if (!valid_signal(data))
647 if (request == PTRACE_SYSCALL)
648 set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
650 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
652 #ifdef TIF_SYSCALL_EMU
653 if (request == PTRACE_SYSEMU || request == PTRACE_SYSEMU_SINGLESTEP)
654 set_tsk_thread_flag(child, TIF_SYSCALL_EMU);
656 clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
659 if (is_singleblock(request)) {
660 if (unlikely(!arch_has_block_step()))
662 user_enable_block_step(child);
663 } else if (is_singlestep(request) || is_sysemu_singlestep(request)) {
664 if (unlikely(!arch_has_single_step()))
666 user_enable_single_step(child);
668 user_disable_single_step(child);
671 child->exit_code = data;
672 wake_up_state(child, __TASK_TRACED);
677 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
679 static const struct user_regset *
680 find_regset(const struct user_regset_view *view, unsigned int type)
682 const struct user_regset *regset;
685 for (n = 0; n < view->n; ++n) {
686 regset = view->regsets + n;
687 if (regset->core_note_type == type)
694 static int ptrace_regset(struct task_struct *task, int req, unsigned int type,
697 const struct user_regset_view *view = task_user_regset_view(task);
698 const struct user_regset *regset = find_regset(view, type);
701 if (!regset || (kiov->iov_len % regset->size) != 0)
704 regset_no = regset - view->regsets;
705 kiov->iov_len = min(kiov->iov_len,
706 (__kernel_size_t) (regset->n * regset->size));
708 if (req == PTRACE_GETREGSET)
709 return copy_regset_to_user(task, view, regset_no, 0,
710 kiov->iov_len, kiov->iov_base);
712 return copy_regset_from_user(task, view, regset_no, 0,
713 kiov->iov_len, kiov->iov_base);
717 * This is declared in linux/regset.h and defined in machine-dependent
718 * code. We put the export here, near the primary machine-neutral use,
719 * to ensure no machine forgets it.
721 EXPORT_SYMBOL_GPL(task_user_regset_view);
724 int ptrace_request(struct task_struct *child, long request,
725 unsigned long addr, unsigned long data)
727 bool seized = child->ptrace & PT_SEIZED;
729 siginfo_t siginfo, *si;
730 void __user *datavp = (void __user *) data;
731 unsigned long __user *datalp = datavp;
735 case PTRACE_PEEKTEXT:
736 case PTRACE_PEEKDATA:
737 return generic_ptrace_peekdata(child, addr, data);
738 case PTRACE_POKETEXT:
739 case PTRACE_POKEDATA:
740 return generic_ptrace_pokedata(child, addr, data);
742 #ifdef PTRACE_OLDSETOPTIONS
743 case PTRACE_OLDSETOPTIONS:
745 case PTRACE_SETOPTIONS:
746 ret = ptrace_setoptions(child, data);
748 case PTRACE_GETEVENTMSG:
749 ret = put_user(child->ptrace_message, datalp);
752 case PTRACE_GETSIGINFO:
753 ret = ptrace_getsiginfo(child, &siginfo);
755 ret = copy_siginfo_to_user(datavp, &siginfo);
758 case PTRACE_SETSIGINFO:
759 if (copy_from_user(&siginfo, datavp, sizeof siginfo))
762 ret = ptrace_setsiginfo(child, &siginfo);
765 case PTRACE_INTERRUPT:
767 * Stop tracee without any side-effect on signal or job
768 * control. At least one trap is guaranteed to happen
769 * after this request. If @child is already trapped, the
770 * current trap is not disturbed and another trap will
771 * happen after the current trap is ended with PTRACE_CONT.
773 * The actual trap might not be PTRACE_EVENT_STOP trap but
774 * the pending condition is cleared regardless.
776 if (unlikely(!seized || !lock_task_sighand(child, &flags)))
780 * INTERRUPT doesn't disturb existing trap sans one
781 * exception. If ptracer issued LISTEN for the current
782 * STOP, this INTERRUPT should clear LISTEN and re-trap
785 if (likely(task_set_jobctl_pending(child, JOBCTL_TRAP_STOP)))
786 ptrace_signal_wake_up(child, child->jobctl & JOBCTL_LISTENING);
788 unlock_task_sighand(child, &flags);
794 * Listen for events. Tracee must be in STOP. It's not
795 * resumed per-se but is not considered to be in TRACED by
796 * wait(2) or ptrace(2). If an async event (e.g. group
797 * stop state change) happens, tracee will enter STOP trap
798 * again. Alternatively, ptracer can issue INTERRUPT to
799 * finish listening and re-trap tracee into STOP.
801 if (unlikely(!seized || !lock_task_sighand(child, &flags)))
804 si = child->last_siginfo;
805 if (likely(si && (si->si_code >> 8) == PTRACE_EVENT_STOP)) {
806 child->jobctl |= JOBCTL_LISTENING;
808 * If NOTIFY is set, it means event happened between
809 * start of this trap and now. Trigger re-trap.
811 if (child->jobctl & JOBCTL_TRAP_NOTIFY)
812 ptrace_signal_wake_up(child, true);
815 unlock_task_sighand(child, &flags);
818 case PTRACE_DETACH: /* detach a process that was attached. */
819 ret = ptrace_detach(child, data);
822 #ifdef CONFIG_BINFMT_ELF_FDPIC
823 case PTRACE_GETFDPIC: {
824 struct mm_struct *mm = get_task_mm(child);
825 unsigned long tmp = 0;
832 case PTRACE_GETFDPIC_EXEC:
833 tmp = mm->context.exec_fdpic_loadmap;
835 case PTRACE_GETFDPIC_INTERP:
836 tmp = mm->context.interp_fdpic_loadmap;
843 ret = put_user(tmp, datalp);
848 #ifdef PTRACE_SINGLESTEP
849 case PTRACE_SINGLESTEP:
851 #ifdef PTRACE_SINGLEBLOCK
852 case PTRACE_SINGLEBLOCK:
856 case PTRACE_SYSEMU_SINGLESTEP:
860 return ptrace_resume(child, request, data);
863 if (child->exit_state) /* already dead */
865 return ptrace_resume(child, request, SIGKILL);
867 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
868 case PTRACE_GETREGSET:
869 case PTRACE_SETREGSET:
872 struct iovec __user *uiov = datavp;
874 if (!access_ok(VERIFY_WRITE, uiov, sizeof(*uiov)))
877 if (__get_user(kiov.iov_base, &uiov->iov_base) ||
878 __get_user(kiov.iov_len, &uiov->iov_len))
881 ret = ptrace_regset(child, request, addr, &kiov);
883 ret = __put_user(kiov.iov_len, &uiov->iov_len);
894 static struct task_struct *ptrace_get_task_struct(pid_t pid)
896 struct task_struct *child;
899 child = find_task_by_vpid(pid);
901 get_task_struct(child);
905 return ERR_PTR(-ESRCH);
909 #ifndef arch_ptrace_attach
910 #define arch_ptrace_attach(child) do { } while (0)
913 SYSCALL_DEFINE4(ptrace, long, request, long, pid, unsigned long, addr,
916 struct task_struct *child;
919 if (request == PTRACE_TRACEME) {
920 ret = ptrace_traceme();
922 arch_ptrace_attach(current);
926 child = ptrace_get_task_struct(pid);
928 ret = PTR_ERR(child);
932 if (request == PTRACE_ATTACH || request == PTRACE_SEIZE) {
933 ret = ptrace_attach(child, request, addr, data);
935 * Some architectures need to do book-keeping after
939 arch_ptrace_attach(child);
940 goto out_put_task_struct;
943 ret = ptrace_check_attach(child, request == PTRACE_KILL ||
944 request == PTRACE_INTERRUPT);
946 goto out_put_task_struct;
948 ret = arch_ptrace(child, request, addr, data);
949 if (ret || request != PTRACE_DETACH)
950 ptrace_unfreeze_traced(child);
953 put_task_struct(child);
958 int generic_ptrace_peekdata(struct task_struct *tsk, unsigned long addr,
964 copied = access_process_vm(tsk, addr, &tmp, sizeof(tmp), 0);
965 if (copied != sizeof(tmp))
967 return put_user(tmp, (unsigned long __user *)data);
970 int generic_ptrace_pokedata(struct task_struct *tsk, unsigned long addr,
975 copied = access_process_vm(tsk, addr, &data, sizeof(data), 1);
976 return (copied == sizeof(data)) ? 0 : -EIO;
979 #if defined CONFIG_COMPAT
980 #include <linux/compat.h>
982 int compat_ptrace_request(struct task_struct *child, compat_long_t request,
983 compat_ulong_t addr, compat_ulong_t data)
985 compat_ulong_t __user *datap = compat_ptr(data);
991 case PTRACE_PEEKTEXT:
992 case PTRACE_PEEKDATA:
993 ret = access_process_vm(child, addr, &word, sizeof(word), 0);
994 if (ret != sizeof(word))
997 ret = put_user(word, datap);
1000 case PTRACE_POKETEXT:
1001 case PTRACE_POKEDATA:
1002 ret = access_process_vm(child, addr, &data, sizeof(data), 1);
1003 ret = (ret != sizeof(data) ? -EIO : 0);
1006 case PTRACE_GETEVENTMSG:
1007 ret = put_user((compat_ulong_t) child->ptrace_message, datap);
1010 case PTRACE_GETSIGINFO:
1011 ret = ptrace_getsiginfo(child, &siginfo);
1013 ret = copy_siginfo_to_user32(
1014 (struct compat_siginfo __user *) datap,
1018 case PTRACE_SETSIGINFO:
1019 memset(&siginfo, 0, sizeof siginfo);
1020 if (copy_siginfo_from_user32(
1021 &siginfo, (struct compat_siginfo __user *) datap))
1024 ret = ptrace_setsiginfo(child, &siginfo);
1026 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
1027 case PTRACE_GETREGSET:
1028 case PTRACE_SETREGSET:
1031 struct compat_iovec __user *uiov =
1032 (struct compat_iovec __user *) datap;
1036 if (!access_ok(VERIFY_WRITE, uiov, sizeof(*uiov)))
1039 if (__get_user(ptr, &uiov->iov_base) ||
1040 __get_user(len, &uiov->iov_len))
1043 kiov.iov_base = compat_ptr(ptr);
1046 ret = ptrace_regset(child, request, addr, &kiov);
1048 ret = __put_user(kiov.iov_len, &uiov->iov_len);
1054 ret = ptrace_request(child, request, addr, data);
1060 asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
1061 compat_long_t addr, compat_long_t data)
1063 struct task_struct *child;
1066 if (request == PTRACE_TRACEME) {
1067 ret = ptrace_traceme();
1071 child = ptrace_get_task_struct(pid);
1072 if (IS_ERR(child)) {
1073 ret = PTR_ERR(child);
1077 if (request == PTRACE_ATTACH || request == PTRACE_SEIZE) {
1078 ret = ptrace_attach(child, request, addr, data);
1080 * Some architectures need to do book-keeping after
1084 arch_ptrace_attach(child);
1085 goto out_put_task_struct;
1088 ret = ptrace_check_attach(child, request == PTRACE_KILL ||
1089 request == PTRACE_INTERRUPT);
1091 ret = compat_arch_ptrace(child, request, addr, data);
1092 if (ret || request != PTRACE_DETACH)
1093 ptrace_unfreeze_traced(child);
1096 out_put_task_struct:
1097 put_task_struct(child);
1101 #endif /* CONFIG_COMPAT */
1103 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1104 int ptrace_get_breakpoints(struct task_struct *tsk)
1106 if (atomic_inc_not_zero(&tsk->ptrace_bp_refcnt))
1112 void ptrace_put_breakpoints(struct task_struct *tsk)
1114 if (atomic_dec_and_test(&tsk->ptrace_bp_refcnt))
1115 flush_ptrace_hw_breakpoint(tsk);
1117 #endif /* CONFIG_HAVE_HW_BREAKPOINT */