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>
29 static int ptrace_trapping_sleep_fn(void *flags)
36 * ptrace a task: make the debugger its new parent and
37 * move it to the ptrace list.
39 * Must be called with the tasklist lock write-held.
41 void __ptrace_link(struct task_struct *child, struct task_struct *new_parent)
43 BUG_ON(!list_empty(&child->ptrace_entry));
44 list_add(&child->ptrace_entry, &new_parent->ptraced);
45 child->parent = new_parent;
49 * __ptrace_unlink - unlink ptracee and restore its execution state
50 * @child: ptracee to be unlinked
52 * Remove @child from the ptrace list, move it back to the original parent,
53 * and restore the execution state so that it conforms to the group stop
56 * Unlinking can happen via two paths - explicit PTRACE_DETACH or ptracer
57 * exiting. For PTRACE_DETACH, unless the ptracee has been killed between
58 * ptrace_check_attach() and here, it's guaranteed to be in TASK_TRACED.
59 * If the ptracer is exiting, the ptracee can be in any state.
61 * After detach, the ptracee should be in a state which conforms to the
62 * group stop. If the group is stopped or in the process of stopping, the
63 * ptracee should be put into TASK_STOPPED; otherwise, it should be woken
64 * up from TASK_TRACED.
66 * If the ptracee is in TASK_TRACED and needs to be moved to TASK_STOPPED,
67 * it goes through TRACED -> RUNNING -> STOPPED transition which is similar
68 * to but in the opposite direction of what happens while attaching to a
69 * stopped task. However, in this direction, the intermediate RUNNING
70 * state is not hidden even from the current ptracer and if it immediately
71 * re-attaches and performs a WNOHANG wait(2), it may fail.
74 * write_lock_irq(tasklist_lock)
76 void __ptrace_unlink(struct task_struct *child)
78 BUG_ON(!child->ptrace);
81 child->parent = child->real_parent;
82 list_del_init(&child->ptrace_entry);
84 spin_lock(&child->sighand->siglock);
87 * Clear all pending traps and TRAPPING. TRAPPING should be
88 * cleared regardless of JOBCTL_STOP_PENDING. Do it explicitly.
90 task_clear_jobctl_pending(child, JOBCTL_TRAP_MASK);
91 task_clear_jobctl_trapping(child);
94 * Reinstate JOBCTL_STOP_PENDING if group stop is in effect and
97 if (!(child->flags & PF_EXITING) &&
98 (child->signal->flags & SIGNAL_STOP_STOPPED ||
99 child->signal->group_stop_count)) {
100 child->jobctl |= JOBCTL_STOP_PENDING;
103 * This is only possible if this thread was cloned by the
104 * traced task running in the stopped group, set the signal
105 * for the future reports.
106 * FIXME: we should change ptrace_init_task() to handle this
109 if (!(child->jobctl & JOBCTL_STOP_SIGMASK))
110 child->jobctl |= SIGSTOP;
114 * If transition to TASK_STOPPED is pending or in TASK_TRACED, kick
115 * @child in the butt. Note that @resume should be used iff @child
116 * is in TASK_TRACED; otherwise, we might unduly disrupt
117 * TASK_KILLABLE sleeps.
119 if (child->jobctl & JOBCTL_STOP_PENDING || task_is_traced(child))
120 signal_wake_up(child, task_is_traced(child));
122 spin_unlock(&child->sighand->siglock);
126 * ptrace_check_attach - check whether ptracee is ready for ptrace operation
127 * @child: ptracee to check for
128 * @ignore_state: don't check whether @child is currently %TASK_TRACED
130 * Check whether @child is being ptraced by %current and ready for further
131 * ptrace operations. If @ignore_state is %false, @child also should be in
132 * %TASK_TRACED state and on return the child is guaranteed to be traced
133 * and not executing. If @ignore_state is %true, @child can be in any
137 * Grabs and releases tasklist_lock and @child->sighand->siglock.
140 * 0 on success, -ESRCH if %child is not ready.
142 int ptrace_check_attach(struct task_struct *child, bool ignore_state)
147 * We take the read lock around doing both checks to close a
148 * possible race where someone else was tracing our child and
149 * detached between these two checks. After this locked check,
150 * we are sure that this is our traced child and that can only
151 * be changed by us so it's not changing right after this.
153 read_lock(&tasklist_lock);
154 if ((child->ptrace & PT_PTRACED) && child->parent == current) {
156 * child->sighand can't be NULL, release_task()
157 * does ptrace_unlink() before __exit_signal().
159 spin_lock_irq(&child->sighand->siglock);
160 WARN_ON_ONCE(task_is_stopped(child));
161 if (ignore_state || (task_is_traced(child) &&
162 !(child->jobctl & JOBCTL_LISTENING)))
164 spin_unlock_irq(&child->sighand->siglock);
166 read_unlock(&tasklist_lock);
168 if (!ret && !ignore_state)
169 ret = wait_task_inactive(child, TASK_TRACED) ? 0 : -ESRCH;
171 /* All systems go.. */
175 static int ptrace_has_cap(struct user_namespace *ns, unsigned int mode)
177 if (mode & PTRACE_MODE_NOAUDIT)
178 return has_ns_capability_noaudit(current, ns, CAP_SYS_PTRACE);
180 return has_ns_capability(current, ns, CAP_SYS_PTRACE);
183 int __ptrace_may_access(struct task_struct *task, unsigned int mode)
185 const struct cred *cred = current_cred(), *tcred;
187 /* May we inspect the given task?
188 * This check is used both for attaching with ptrace
189 * and for allowing access to sensitive information in /proc.
191 * ptrace_attach denies several cases that /proc allows
192 * because setting up the necessary parent/child relationship
193 * or halting the specified task is impossible.
196 /* Don't let security modules deny introspection */
200 tcred = __task_cred(task);
201 if (cred->user->user_ns == tcred->user->user_ns &&
202 (cred->uid == tcred->euid &&
203 cred->uid == tcred->suid &&
204 cred->uid == tcred->uid &&
205 cred->gid == tcred->egid &&
206 cred->gid == tcred->sgid &&
207 cred->gid == tcred->gid))
209 if (ptrace_has_cap(tcred->user->user_ns, mode))
217 dumpable = get_dumpable(task->mm);
218 if (!dumpable && !ptrace_has_cap(task_user_ns(task), mode))
221 return security_ptrace_access_check(task, mode);
224 bool ptrace_may_access(struct task_struct *task, unsigned int mode)
228 err = __ptrace_may_access(task, mode);
233 static int ptrace_attach(struct task_struct *task, long request,
236 bool seize = (request == PTRACE_SEIZE);
240 * SEIZE will enable new ptrace behaviors which will be implemented
241 * gradually. SEIZE_DEVEL is used to prevent applications
242 * expecting full SEIZE behaviors trapping on kernel commits which
243 * are still in the process of implementing them.
245 * Only test programs for new ptrace behaviors being implemented
246 * should set SEIZE_DEVEL. If unset, SEIZE will fail with -EIO.
248 * Once SEIZE behaviors are completely implemented, this flag and
249 * the following test will be removed.
252 if (seize && !(flags & PTRACE_SEIZE_DEVEL))
258 if (unlikely(task->flags & PF_KTHREAD))
260 if (same_thread_group(task, current))
264 * Protect exec's credential calculations against our interference;
265 * interference; SUID, SGID and LSM creds get determined differently
268 retval = -ERESTARTNOINTR;
269 if (mutex_lock_interruptible(&task->signal->cred_guard_mutex))
273 retval = __ptrace_may_access(task, PTRACE_MODE_ATTACH);
278 write_lock_irq(&tasklist_lock);
280 if (unlikely(task->exit_state))
281 goto unlock_tasklist;
283 goto unlock_tasklist;
285 task->ptrace = PT_PTRACED;
287 task->ptrace |= PT_SEIZED;
288 if (ns_capable(task_user_ns(task), CAP_SYS_PTRACE))
289 task->ptrace |= PT_PTRACE_CAP;
291 __ptrace_link(task, current);
293 /* SEIZE doesn't trap tracee on attach */
295 send_sig_info(SIGSTOP, SEND_SIG_FORCED, task);
297 spin_lock(&task->sighand->siglock);
300 * If the task is already STOPPED, set JOBCTL_TRAP_STOP and
301 * TRAPPING, and kick it so that it transits to TRACED. TRAPPING
302 * will be cleared if the child completes the transition or any
303 * event which clears the group stop states happens. We'll wait
304 * for the transition to complete before returning from this
307 * This hides STOPPED -> RUNNING -> TRACED transition from the
308 * attaching thread but a different thread in the same group can
309 * still observe the transient RUNNING state. IOW, if another
310 * thread's WNOHANG wait(2) on the stopped tracee races against
311 * ATTACH, the wait(2) may fail due to the transient RUNNING.
313 * The following task_is_stopped() test is safe as both transitions
314 * in and out of STOPPED are protected by siglock.
316 if (task_is_stopped(task) &&
317 task_set_jobctl_pending(task, JOBCTL_TRAP_STOP | JOBCTL_TRAPPING))
318 signal_wake_up(task, 1);
320 spin_unlock(&task->sighand->siglock);
324 write_unlock_irq(&tasklist_lock);
326 mutex_unlock(&task->signal->cred_guard_mutex);
329 wait_on_bit(&task->jobctl, JOBCTL_TRAPPING_BIT,
330 ptrace_trapping_sleep_fn, TASK_UNINTERRUPTIBLE);
331 proc_ptrace_connector(task, PTRACE_ATTACH);
338 * ptrace_traceme -- helper for PTRACE_TRACEME
340 * Performs checks and sets PT_PTRACED.
341 * Should be used by all ptrace implementations for PTRACE_TRACEME.
343 static int ptrace_traceme(void)
347 write_lock_irq(&tasklist_lock);
348 /* Are we already being traced? */
349 if (!current->ptrace) {
350 ret = security_ptrace_traceme(current->parent);
352 * Check PF_EXITING to ensure ->real_parent has not passed
353 * exit_ptrace(). Otherwise we don't report the error but
354 * pretend ->real_parent untraces us right after return.
356 if (!ret && !(current->real_parent->flags & PF_EXITING)) {
357 current->ptrace = PT_PTRACED;
358 __ptrace_link(current, current->real_parent);
361 write_unlock_irq(&tasklist_lock);
367 * Called with irqs disabled, returns true if childs should reap themselves.
369 static int ignoring_children(struct sighand_struct *sigh)
372 spin_lock(&sigh->siglock);
373 ret = (sigh->action[SIGCHLD-1].sa.sa_handler == SIG_IGN) ||
374 (sigh->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT);
375 spin_unlock(&sigh->siglock);
380 * Called with tasklist_lock held for writing.
381 * Unlink a traced task, and clean it up if it was a traced zombie.
382 * Return true if it needs to be reaped with release_task().
383 * (We can't call release_task() here because we already hold tasklist_lock.)
385 * If it's a zombie, our attachedness prevented normal parent notification
386 * or self-reaping. Do notification now if it would have happened earlier.
387 * If it should reap itself, return true.
389 * If it's our own child, there is no notification to do. But if our normal
390 * children self-reap, then this child was prevented by ptrace and we must
391 * reap it now, in that case we must also wake up sub-threads sleeping in
394 static bool __ptrace_detach(struct task_struct *tracer, struct task_struct *p)
400 if (p->exit_state != EXIT_ZOMBIE)
403 dead = !thread_group_leader(p);
405 if (!dead && thread_group_empty(p)) {
406 if (!same_thread_group(p->real_parent, tracer))
407 dead = do_notify_parent(p, p->exit_signal);
408 else if (ignoring_children(tracer->sighand)) {
409 __wake_up_parent(p, tracer);
413 /* Mark it as in the process of being reaped. */
415 p->exit_state = EXIT_DEAD;
419 static int ptrace_detach(struct task_struct *child, unsigned int data)
423 if (!valid_signal(data))
426 /* Architecture-specific hardware disable .. */
427 ptrace_disable(child);
428 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
430 write_lock_irq(&tasklist_lock);
432 * This child can be already killed. Make sure de_thread() or
433 * our sub-thread doing do_wait() didn't do release_task() yet.
436 child->exit_code = data;
437 dead = __ptrace_detach(current, child);
439 write_unlock_irq(&tasklist_lock);
441 proc_ptrace_connector(child, PTRACE_DETACH);
449 * Detach all tasks we were using ptrace on. Called with tasklist held
450 * for writing, and returns with it held too. But note it can release
451 * and reacquire the lock.
453 void exit_ptrace(struct task_struct *tracer)
454 __releases(&tasklist_lock)
455 __acquires(&tasklist_lock)
457 struct task_struct *p, *n;
458 LIST_HEAD(ptrace_dead);
460 if (likely(list_empty(&tracer->ptraced)))
463 list_for_each_entry_safe(p, n, &tracer->ptraced, ptrace_entry) {
464 if (__ptrace_detach(tracer, p))
465 list_add(&p->ptrace_entry, &ptrace_dead);
468 write_unlock_irq(&tasklist_lock);
469 BUG_ON(!list_empty(&tracer->ptraced));
471 list_for_each_entry_safe(p, n, &ptrace_dead, ptrace_entry) {
472 list_del_init(&p->ptrace_entry);
476 write_lock_irq(&tasklist_lock);
479 int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len)
485 int this_len, retval;
487 this_len = (len > sizeof(buf)) ? sizeof(buf) : len;
488 retval = access_process_vm(tsk, src, buf, this_len, 0);
494 if (copy_to_user(dst, buf, retval))
504 int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len)
510 int this_len, retval;
512 this_len = (len > sizeof(buf)) ? sizeof(buf) : len;
513 if (copy_from_user(buf, src, this_len))
515 retval = access_process_vm(tsk, dst, buf, this_len, 1);
529 static int ptrace_setoptions(struct task_struct *child, unsigned long data)
531 if (data & ~(unsigned long)PTRACE_O_MASK)
534 child->ptrace &= ~PT_TRACE_MASK;
536 if (data & PTRACE_O_TRACESYSGOOD)
537 child->ptrace |= PT_TRACESYSGOOD;
539 if (data & PTRACE_O_TRACEFORK)
540 child->ptrace |= PT_TRACE_FORK;
542 if (data & PTRACE_O_TRACEVFORK)
543 child->ptrace |= PT_TRACE_VFORK;
545 if (data & PTRACE_O_TRACECLONE)
546 child->ptrace |= PT_TRACE_CLONE;
548 if (data & PTRACE_O_TRACEEXEC)
549 child->ptrace |= PT_TRACE_EXEC;
551 if (data & PTRACE_O_TRACEVFORKDONE)
552 child->ptrace |= PT_TRACE_VFORK_DONE;
554 if (data & PTRACE_O_TRACEEXIT)
555 child->ptrace |= PT_TRACE_EXIT;
560 static int ptrace_getsiginfo(struct task_struct *child, siginfo_t *info)
565 if (lock_task_sighand(child, &flags)) {
567 if (likely(child->last_siginfo != NULL)) {
568 *info = *child->last_siginfo;
571 unlock_task_sighand(child, &flags);
576 static int ptrace_setsiginfo(struct task_struct *child, const siginfo_t *info)
581 if (lock_task_sighand(child, &flags)) {
583 if (likely(child->last_siginfo != NULL)) {
584 *child->last_siginfo = *info;
587 unlock_task_sighand(child, &flags);
593 #ifdef PTRACE_SINGLESTEP
594 #define is_singlestep(request) ((request) == PTRACE_SINGLESTEP)
596 #define is_singlestep(request) 0
599 #ifdef PTRACE_SINGLEBLOCK
600 #define is_singleblock(request) ((request) == PTRACE_SINGLEBLOCK)
602 #define is_singleblock(request) 0
606 #define is_sysemu_singlestep(request) ((request) == PTRACE_SYSEMU_SINGLESTEP)
608 #define is_sysemu_singlestep(request) 0
611 static int ptrace_resume(struct task_struct *child, long request,
614 if (!valid_signal(data))
617 if (request == PTRACE_SYSCALL)
618 set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
620 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
622 #ifdef TIF_SYSCALL_EMU
623 if (request == PTRACE_SYSEMU || request == PTRACE_SYSEMU_SINGLESTEP)
624 set_tsk_thread_flag(child, TIF_SYSCALL_EMU);
626 clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
629 if (is_singleblock(request)) {
630 if (unlikely(!arch_has_block_step()))
632 user_enable_block_step(child);
633 } else if (is_singlestep(request) || is_sysemu_singlestep(request)) {
634 if (unlikely(!arch_has_single_step()))
636 user_enable_single_step(child);
638 user_disable_single_step(child);
641 child->exit_code = data;
642 wake_up_state(child, __TASK_TRACED);
647 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
649 static const struct user_regset *
650 find_regset(const struct user_regset_view *view, unsigned int type)
652 const struct user_regset *regset;
655 for (n = 0; n < view->n; ++n) {
656 regset = view->regsets + n;
657 if (regset->core_note_type == type)
664 static int ptrace_regset(struct task_struct *task, int req, unsigned int type,
667 const struct user_regset_view *view = task_user_regset_view(task);
668 const struct user_regset *regset = find_regset(view, type);
671 if (!regset || (kiov->iov_len % regset->size) != 0)
674 regset_no = regset - view->regsets;
675 kiov->iov_len = min(kiov->iov_len,
676 (__kernel_size_t) (regset->n * regset->size));
678 if (req == PTRACE_GETREGSET)
679 return copy_regset_to_user(task, view, regset_no, 0,
680 kiov->iov_len, kiov->iov_base);
682 return copy_regset_from_user(task, view, regset_no, 0,
683 kiov->iov_len, kiov->iov_base);
688 int ptrace_request(struct task_struct *child, long request,
689 unsigned long addr, unsigned long data)
691 bool seized = child->ptrace & PT_SEIZED;
693 siginfo_t siginfo, *si;
694 void __user *datavp = (void __user *) data;
695 unsigned long __user *datalp = datavp;
699 case PTRACE_PEEKTEXT:
700 case PTRACE_PEEKDATA:
701 return generic_ptrace_peekdata(child, addr, data);
702 case PTRACE_POKETEXT:
703 case PTRACE_POKEDATA:
704 return generic_ptrace_pokedata(child, addr, data);
706 #ifdef PTRACE_OLDSETOPTIONS
707 case PTRACE_OLDSETOPTIONS:
709 case PTRACE_SETOPTIONS:
710 ret = ptrace_setoptions(child, data);
712 case PTRACE_GETEVENTMSG:
713 ret = put_user(child->ptrace_message, datalp);
716 case PTRACE_GETSIGINFO:
717 ret = ptrace_getsiginfo(child, &siginfo);
719 ret = copy_siginfo_to_user(datavp, &siginfo);
722 case PTRACE_SETSIGINFO:
723 if (copy_from_user(&siginfo, datavp, sizeof siginfo))
726 ret = ptrace_setsiginfo(child, &siginfo);
729 case PTRACE_INTERRUPT:
731 * Stop tracee without any side-effect on signal or job
732 * control. At least one trap is guaranteed to happen
733 * after this request. If @child is already trapped, the
734 * current trap is not disturbed and another trap will
735 * happen after the current trap is ended with PTRACE_CONT.
737 * The actual trap might not be PTRACE_EVENT_STOP trap but
738 * the pending condition is cleared regardless.
740 if (unlikely(!seized || !lock_task_sighand(child, &flags)))
744 * INTERRUPT doesn't disturb existing trap sans one
745 * exception. If ptracer issued LISTEN for the current
746 * STOP, this INTERRUPT should clear LISTEN and re-trap
749 if (likely(task_set_jobctl_pending(child, JOBCTL_TRAP_STOP)))
750 signal_wake_up(child, child->jobctl & JOBCTL_LISTENING);
752 unlock_task_sighand(child, &flags);
758 * Listen for events. Tracee must be in STOP. It's not
759 * resumed per-se but is not considered to be in TRACED by
760 * wait(2) or ptrace(2). If an async event (e.g. group
761 * stop state change) happens, tracee will enter STOP trap
762 * again. Alternatively, ptracer can issue INTERRUPT to
763 * finish listening and re-trap tracee into STOP.
765 if (unlikely(!seized || !lock_task_sighand(child, &flags)))
768 si = child->last_siginfo;
769 if (likely(si && (si->si_code >> 8) == PTRACE_EVENT_STOP)) {
770 child->jobctl |= JOBCTL_LISTENING;
772 * If NOTIFY is set, it means event happened between
773 * start of this trap and now. Trigger re-trap.
775 if (child->jobctl & JOBCTL_TRAP_NOTIFY)
776 signal_wake_up(child, true);
779 unlock_task_sighand(child, &flags);
782 case PTRACE_DETACH: /* detach a process that was attached. */
783 ret = ptrace_detach(child, data);
786 #ifdef CONFIG_BINFMT_ELF_FDPIC
787 case PTRACE_GETFDPIC: {
788 struct mm_struct *mm = get_task_mm(child);
789 unsigned long tmp = 0;
796 case PTRACE_GETFDPIC_EXEC:
797 tmp = mm->context.exec_fdpic_loadmap;
799 case PTRACE_GETFDPIC_INTERP:
800 tmp = mm->context.interp_fdpic_loadmap;
807 ret = put_user(tmp, datalp);
812 #ifdef PTRACE_SINGLESTEP
813 case PTRACE_SINGLESTEP:
815 #ifdef PTRACE_SINGLEBLOCK
816 case PTRACE_SINGLEBLOCK:
820 case PTRACE_SYSEMU_SINGLESTEP:
824 return ptrace_resume(child, request, data);
827 if (child->exit_state) /* already dead */
829 return ptrace_resume(child, request, SIGKILL);
831 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
832 case PTRACE_GETREGSET:
833 case PTRACE_SETREGSET:
836 struct iovec __user *uiov = datavp;
838 if (!access_ok(VERIFY_WRITE, uiov, sizeof(*uiov)))
841 if (__get_user(kiov.iov_base, &uiov->iov_base) ||
842 __get_user(kiov.iov_len, &uiov->iov_len))
845 ret = ptrace_regset(child, request, addr, &kiov);
847 ret = __put_user(kiov.iov_len, &uiov->iov_len);
858 static struct task_struct *ptrace_get_task_struct(pid_t pid)
860 struct task_struct *child;
863 child = find_task_by_vpid(pid);
865 get_task_struct(child);
869 return ERR_PTR(-ESRCH);
873 #ifndef arch_ptrace_attach
874 #define arch_ptrace_attach(child) do { } while (0)
877 SYSCALL_DEFINE4(ptrace, long, request, long, pid, unsigned long, addr,
880 struct task_struct *child;
883 if (request == PTRACE_TRACEME) {
884 ret = ptrace_traceme();
886 arch_ptrace_attach(current);
890 child = ptrace_get_task_struct(pid);
892 ret = PTR_ERR(child);
896 if (request == PTRACE_ATTACH || request == PTRACE_SEIZE) {
897 ret = ptrace_attach(child, request, data);
899 * Some architectures need to do book-keeping after
903 arch_ptrace_attach(child);
904 goto out_put_task_struct;
907 ret = ptrace_check_attach(child, request == PTRACE_KILL ||
908 request == PTRACE_INTERRUPT);
910 goto out_put_task_struct;
912 ret = arch_ptrace(child, request, addr, data);
915 put_task_struct(child);
920 int generic_ptrace_peekdata(struct task_struct *tsk, unsigned long addr,
926 copied = access_process_vm(tsk, addr, &tmp, sizeof(tmp), 0);
927 if (copied != sizeof(tmp))
929 return put_user(tmp, (unsigned long __user *)data);
932 int generic_ptrace_pokedata(struct task_struct *tsk, unsigned long addr,
937 copied = access_process_vm(tsk, addr, &data, sizeof(data), 1);
938 return (copied == sizeof(data)) ? 0 : -EIO;
941 #if defined CONFIG_COMPAT
942 #include <linux/compat.h>
944 int compat_ptrace_request(struct task_struct *child, compat_long_t request,
945 compat_ulong_t addr, compat_ulong_t data)
947 compat_ulong_t __user *datap = compat_ptr(data);
953 case PTRACE_PEEKTEXT:
954 case PTRACE_PEEKDATA:
955 ret = access_process_vm(child, addr, &word, sizeof(word), 0);
956 if (ret != sizeof(word))
959 ret = put_user(word, datap);
962 case PTRACE_POKETEXT:
963 case PTRACE_POKEDATA:
964 ret = access_process_vm(child, addr, &data, sizeof(data), 1);
965 ret = (ret != sizeof(data) ? -EIO : 0);
968 case PTRACE_GETEVENTMSG:
969 ret = put_user((compat_ulong_t) child->ptrace_message, datap);
972 case PTRACE_GETSIGINFO:
973 ret = ptrace_getsiginfo(child, &siginfo);
975 ret = copy_siginfo_to_user32(
976 (struct compat_siginfo __user *) datap,
980 case PTRACE_SETSIGINFO:
981 memset(&siginfo, 0, sizeof siginfo);
982 if (copy_siginfo_from_user32(
983 &siginfo, (struct compat_siginfo __user *) datap))
986 ret = ptrace_setsiginfo(child, &siginfo);
988 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
989 case PTRACE_GETREGSET:
990 case PTRACE_SETREGSET:
993 struct compat_iovec __user *uiov =
994 (struct compat_iovec __user *) datap;
998 if (!access_ok(VERIFY_WRITE, uiov, sizeof(*uiov)))
1001 if (__get_user(ptr, &uiov->iov_base) ||
1002 __get_user(len, &uiov->iov_len))
1005 kiov.iov_base = compat_ptr(ptr);
1008 ret = ptrace_regset(child, request, addr, &kiov);
1010 ret = __put_user(kiov.iov_len, &uiov->iov_len);
1016 ret = ptrace_request(child, request, addr, data);
1022 asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
1023 compat_long_t addr, compat_long_t data)
1025 struct task_struct *child;
1028 if (request == PTRACE_TRACEME) {
1029 ret = ptrace_traceme();
1033 child = ptrace_get_task_struct(pid);
1034 if (IS_ERR(child)) {
1035 ret = PTR_ERR(child);
1039 if (request == PTRACE_ATTACH || request == PTRACE_SEIZE) {
1040 ret = ptrace_attach(child, request, data);
1042 * Some architectures need to do book-keeping after
1046 arch_ptrace_attach(child);
1047 goto out_put_task_struct;
1050 ret = ptrace_check_attach(child, request == PTRACE_KILL ||
1051 request == PTRACE_INTERRUPT);
1053 ret = compat_arch_ptrace(child, request, addr, data);
1055 out_put_task_struct:
1056 put_task_struct(child);
1060 #endif /* CONFIG_COMPAT */
1062 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1063 int ptrace_get_breakpoints(struct task_struct *tsk)
1065 if (atomic_inc_not_zero(&tsk->ptrace_bp_refcnt))
1071 void ptrace_put_breakpoints(struct task_struct *tsk)
1073 if (atomic_dec_and_test(&tsk->ptrace_bp_refcnt))
1074 flush_ptrace_hw_breakpoint(tsk);
1076 #endif /* CONFIG_HAVE_HW_BREAKPOINT */