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/module.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>
28 static int ptrace_trapping_sleep_fn(void *flags
)
35 * ptrace a task: make the debugger its new parent and
36 * move it to the ptrace list.
38 * Must be called with the tasklist lock write-held.
40 void __ptrace_link(struct task_struct
*child
, struct task_struct
*new_parent
)
42 BUG_ON(!list_empty(&child
->ptrace_entry
));
43 list_add(&child
->ptrace_entry
, &new_parent
->ptraced
);
44 child
->parent
= new_parent
;
48 * __ptrace_unlink - unlink ptracee and restore its execution state
49 * @child: ptracee to be unlinked
51 * Remove @child from the ptrace list, move it back to the original parent,
52 * and restore the execution state so that it conforms to the group stop
55 * Unlinking can happen via two paths - explicit PTRACE_DETACH or ptracer
56 * exiting. For PTRACE_DETACH, unless the ptracee has been killed between
57 * ptrace_check_attach() and here, it's guaranteed to be in TASK_TRACED.
58 * If the ptracer is exiting, the ptracee can be in any state.
60 * After detach, the ptracee should be in a state which conforms to the
61 * group stop. If the group is stopped or in the process of stopping, the
62 * ptracee should be put into TASK_STOPPED; otherwise, it should be woken
63 * up from TASK_TRACED.
65 * If the ptracee is in TASK_TRACED and needs to be moved to TASK_STOPPED,
66 * it goes through TRACED -> RUNNING -> STOPPED transition which is similar
67 * to but in the opposite direction of what happens while attaching to a
68 * stopped task. However, in this direction, the intermediate RUNNING
69 * state is not hidden even from the current ptracer and if it immediately
70 * re-attaches and performs a WNOHANG wait(2), it may fail.
73 * write_lock_irq(tasklist_lock)
75 void __ptrace_unlink(struct task_struct
*child
)
77 BUG_ON(!child
->ptrace
);
80 child
->parent
= child
->real_parent
;
81 list_del_init(&child
->ptrace_entry
);
83 spin_lock(&child
->sighand
->siglock
);
86 * Clear all pending traps and TRAPPING. TRAPPING should be
87 * cleared regardless of JOBCTL_STOP_PENDING. Do it explicitly.
89 task_clear_jobctl_pending(child
, JOBCTL_TRAP_MASK
);
90 task_clear_jobctl_trapping(child
);
93 * Reinstate JOBCTL_STOP_PENDING if group stop is in effect and
96 if (!(child
->flags
& PF_EXITING
) &&
97 (child
->signal
->flags
& SIGNAL_STOP_STOPPED
||
98 child
->signal
->group_stop_count
))
99 child
->jobctl
|= JOBCTL_STOP_PENDING
;
102 * If transition to TASK_STOPPED is pending or in TASK_TRACED, kick
103 * @child in the butt. Note that @resume should be used iff @child
104 * is in TASK_TRACED; otherwise, we might unduly disrupt
105 * TASK_KILLABLE sleeps.
107 if (child
->jobctl
& JOBCTL_STOP_PENDING
|| task_is_traced(child
))
108 signal_wake_up(child
, task_is_traced(child
));
110 spin_unlock(&child
->sighand
->siglock
);
114 * ptrace_check_attach - check whether ptracee is ready for ptrace operation
115 * @child: ptracee to check for
116 * @ignore_state: don't check whether @child is currently %TASK_TRACED
118 * Check whether @child is being ptraced by %current and ready for further
119 * ptrace operations. If @ignore_state is %false, @child also should be in
120 * %TASK_TRACED state and on return the child is guaranteed to be traced
121 * and not executing. If @ignore_state is %true, @child can be in any
125 * Grabs and releases tasklist_lock and @child->sighand->siglock.
128 * 0 on success, -ESRCH if %child is not ready.
130 int ptrace_check_attach(struct task_struct
*child
, bool ignore_state
)
135 * We take the read lock around doing both checks to close a
136 * possible race where someone else was tracing our child and
137 * detached between these two checks. After this locked check,
138 * we are sure that this is our traced child and that can only
139 * be changed by us so it's not changing right after this.
141 read_lock(&tasklist_lock
);
142 if ((child
->ptrace
& PT_PTRACED
) && child
->parent
== current
) {
144 * child->sighand can't be NULL, release_task()
145 * does ptrace_unlink() before __exit_signal().
147 spin_lock_irq(&child
->sighand
->siglock
);
148 WARN_ON_ONCE(task_is_stopped(child
));
149 if (ignore_state
|| (task_is_traced(child
) &&
150 !(child
->jobctl
& JOBCTL_LISTENING
)))
152 spin_unlock_irq(&child
->sighand
->siglock
);
154 read_unlock(&tasklist_lock
);
156 if (!ret
&& !ignore_state
)
157 ret
= wait_task_inactive(child
, TASK_TRACED
) ? 0 : -ESRCH
;
159 /* All systems go.. */
163 int __ptrace_may_access(struct task_struct
*task
, unsigned int mode
)
165 const struct cred
*cred
= current_cred(), *tcred
;
167 /* May we inspect the given task?
168 * This check is used both for attaching with ptrace
169 * and for allowing access to sensitive information in /proc.
171 * ptrace_attach denies several cases that /proc allows
172 * because setting up the necessary parent/child relationship
173 * or halting the specified task is impossible.
176 /* Don't let security modules deny introspection */
180 tcred
= __task_cred(task
);
181 if (cred
->user
->user_ns
== tcred
->user
->user_ns
&&
182 (cred
->uid
== tcred
->euid
&&
183 cred
->uid
== tcred
->suid
&&
184 cred
->uid
== tcred
->uid
&&
185 cred
->gid
== tcred
->egid
&&
186 cred
->gid
== tcred
->sgid
&&
187 cred
->gid
== tcred
->gid
))
189 if (ns_capable(tcred
->user
->user_ns
, CAP_SYS_PTRACE
))
197 dumpable
= get_dumpable(task
->mm
);
198 if (!dumpable
&& !task_ns_capable(task
, CAP_SYS_PTRACE
))
201 return security_ptrace_access_check(task
, mode
);
204 bool ptrace_may_access(struct task_struct
*task
, unsigned int mode
)
208 err
= __ptrace_may_access(task
, mode
);
213 static int ptrace_attach(struct task_struct
*task
, long request
,
216 bool seize
= (request
== PTRACE_SEIZE
);
220 * SEIZE will enable new ptrace behaviors which will be implemented
221 * gradually. SEIZE_DEVEL is used to prevent applications
222 * expecting full SEIZE behaviors trapping on kernel commits which
223 * are still in the process of implementing them.
225 * Only test programs for new ptrace behaviors being implemented
226 * should set SEIZE_DEVEL. If unset, SEIZE will fail with -EIO.
228 * Once SEIZE behaviors are completely implemented, this flag and
229 * the following test will be removed.
232 if (seize
&& !(flags
& PTRACE_SEIZE_DEVEL
))
238 if (unlikely(task
->flags
& PF_KTHREAD
))
240 if (same_thread_group(task
, current
))
244 * Protect exec's credential calculations against our interference;
245 * interference; SUID, SGID and LSM creds get determined differently
248 retval
= -ERESTARTNOINTR
;
249 if (mutex_lock_interruptible(&task
->signal
->cred_guard_mutex
))
253 retval
= __ptrace_may_access(task
, PTRACE_MODE_ATTACH
);
258 write_lock_irq(&tasklist_lock
);
260 if (unlikely(task
->exit_state
))
261 goto unlock_tasklist
;
263 goto unlock_tasklist
;
265 task
->ptrace
= PT_PTRACED
;
267 task
->ptrace
|= PT_SEIZED
;
268 if (task_ns_capable(task
, CAP_SYS_PTRACE
))
269 task
->ptrace
|= PT_PTRACE_CAP
;
271 __ptrace_link(task
, current
);
273 /* SEIZE doesn't trap tracee on attach */
275 send_sig_info(SIGSTOP
, SEND_SIG_FORCED
, task
);
277 spin_lock(&task
->sighand
->siglock
);
280 * If the task is already STOPPED, set JOBCTL_TRAP_STOP and
281 * TRAPPING, and kick it so that it transits to TRACED. TRAPPING
282 * will be cleared if the child completes the transition or any
283 * event which clears the group stop states happens. We'll wait
284 * for the transition to complete before returning from this
287 * This hides STOPPED -> RUNNING -> TRACED transition from the
288 * attaching thread but a different thread in the same group can
289 * still observe the transient RUNNING state. IOW, if another
290 * thread's WNOHANG wait(2) on the stopped tracee races against
291 * ATTACH, the wait(2) may fail due to the transient RUNNING.
293 * The following task_is_stopped() test is safe as both transitions
294 * in and out of STOPPED are protected by siglock.
296 if (task_is_stopped(task
) &&
297 task_set_jobctl_pending(task
, JOBCTL_TRAP_STOP
| JOBCTL_TRAPPING
))
298 signal_wake_up(task
, 1);
300 spin_unlock(&task
->sighand
->siglock
);
304 write_unlock_irq(&tasklist_lock
);
306 mutex_unlock(&task
->signal
->cred_guard_mutex
);
309 wait_on_bit(&task
->jobctl
, JOBCTL_TRAPPING_BIT
,
310 ptrace_trapping_sleep_fn
, TASK_UNINTERRUPTIBLE
);
315 * ptrace_traceme -- helper for PTRACE_TRACEME
317 * Performs checks and sets PT_PTRACED.
318 * Should be used by all ptrace implementations for PTRACE_TRACEME.
320 static int ptrace_traceme(void)
324 write_lock_irq(&tasklist_lock
);
325 /* Are we already being traced? */
326 if (!current
->ptrace
) {
327 ret
= security_ptrace_traceme(current
->parent
);
329 * Check PF_EXITING to ensure ->real_parent has not passed
330 * exit_ptrace(). Otherwise we don't report the error but
331 * pretend ->real_parent untraces us right after return.
333 if (!ret
&& !(current
->real_parent
->flags
& PF_EXITING
)) {
334 current
->ptrace
= PT_PTRACED
;
335 __ptrace_link(current
, current
->real_parent
);
338 write_unlock_irq(&tasklist_lock
);
344 * Called with irqs disabled, returns true if childs should reap themselves.
346 static int ignoring_children(struct sighand_struct
*sigh
)
349 spin_lock(&sigh
->siglock
);
350 ret
= (sigh
->action
[SIGCHLD
-1].sa
.sa_handler
== SIG_IGN
) ||
351 (sigh
->action
[SIGCHLD
-1].sa
.sa_flags
& SA_NOCLDWAIT
);
352 spin_unlock(&sigh
->siglock
);
357 * Called with tasklist_lock held for writing.
358 * Unlink a traced task, and clean it up if it was a traced zombie.
359 * Return true if it needs to be reaped with release_task().
360 * (We can't call release_task() here because we already hold tasklist_lock.)
362 * If it's a zombie, our attachedness prevented normal parent notification
363 * or self-reaping. Do notification now if it would have happened earlier.
364 * If it should reap itself, return true.
366 * If it's our own child, there is no notification to do. But if our normal
367 * children self-reap, then this child was prevented by ptrace and we must
368 * reap it now, in that case we must also wake up sub-threads sleeping in
371 static bool __ptrace_detach(struct task_struct
*tracer
, struct task_struct
*p
)
375 if (p
->exit_state
== EXIT_ZOMBIE
) {
376 if (!task_detached(p
) && thread_group_empty(p
)) {
377 if (!same_thread_group(p
->real_parent
, tracer
))
378 do_notify_parent(p
, p
->exit_signal
);
379 else if (ignoring_children(tracer
->sighand
)) {
380 __wake_up_parent(p
, tracer
);
384 if (task_detached(p
)) {
385 /* Mark it as in the process of being reaped. */
386 p
->exit_state
= EXIT_DEAD
;
394 static int ptrace_detach(struct task_struct
*child
, unsigned int data
)
398 if (!valid_signal(data
))
401 /* Architecture-specific hardware disable .. */
402 ptrace_disable(child
);
403 clear_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
405 write_lock_irq(&tasklist_lock
);
407 * This child can be already killed. Make sure de_thread() or
408 * our sub-thread doing do_wait() didn't do release_task() yet.
411 child
->exit_code
= data
;
412 dead
= __ptrace_detach(current
, child
);
414 write_unlock_irq(&tasklist_lock
);
423 * Detach all tasks we were using ptrace on. Called with tasklist held
424 * for writing, and returns with it held too. But note it can release
425 * and reacquire the lock.
427 void exit_ptrace(struct task_struct
*tracer
)
428 __releases(&tasklist_lock
)
429 __acquires(&tasklist_lock
)
431 struct task_struct
*p
, *n
;
432 LIST_HEAD(ptrace_dead
);
434 if (likely(list_empty(&tracer
->ptraced
)))
437 list_for_each_entry_safe(p
, n
, &tracer
->ptraced
, ptrace_entry
) {
438 if (__ptrace_detach(tracer
, p
))
439 list_add(&p
->ptrace_entry
, &ptrace_dead
);
442 write_unlock_irq(&tasklist_lock
);
443 BUG_ON(!list_empty(&tracer
->ptraced
));
445 list_for_each_entry_safe(p
, n
, &ptrace_dead
, ptrace_entry
) {
446 list_del_init(&p
->ptrace_entry
);
450 write_lock_irq(&tasklist_lock
);
453 int ptrace_readdata(struct task_struct
*tsk
, unsigned long src
, char __user
*dst
, int len
)
459 int this_len
, retval
;
461 this_len
= (len
> sizeof(buf
)) ? sizeof(buf
) : len
;
462 retval
= access_process_vm(tsk
, src
, buf
, this_len
, 0);
468 if (copy_to_user(dst
, buf
, retval
))
478 int ptrace_writedata(struct task_struct
*tsk
, char __user
*src
, unsigned long dst
, int len
)
484 int this_len
, retval
;
486 this_len
= (len
> sizeof(buf
)) ? sizeof(buf
) : len
;
487 if (copy_from_user(buf
, src
, this_len
))
489 retval
= access_process_vm(tsk
, dst
, buf
, this_len
, 1);
503 static int ptrace_setoptions(struct task_struct
*child
, unsigned long data
)
505 child
->ptrace
&= ~PT_TRACE_MASK
;
507 if (data
& PTRACE_O_TRACESYSGOOD
)
508 child
->ptrace
|= PT_TRACESYSGOOD
;
510 if (data
& PTRACE_O_TRACEFORK
)
511 child
->ptrace
|= PT_TRACE_FORK
;
513 if (data
& PTRACE_O_TRACEVFORK
)
514 child
->ptrace
|= PT_TRACE_VFORK
;
516 if (data
& PTRACE_O_TRACECLONE
)
517 child
->ptrace
|= PT_TRACE_CLONE
;
519 if (data
& PTRACE_O_TRACEEXEC
)
520 child
->ptrace
|= PT_TRACE_EXEC
;
522 if (data
& PTRACE_O_TRACEVFORKDONE
)
523 child
->ptrace
|= PT_TRACE_VFORK_DONE
;
525 if (data
& PTRACE_O_TRACEEXIT
)
526 child
->ptrace
|= PT_TRACE_EXIT
;
528 return (data
& ~PTRACE_O_MASK
) ? -EINVAL
: 0;
531 static int ptrace_getsiginfo(struct task_struct
*child
, siginfo_t
*info
)
536 if (lock_task_sighand(child
, &flags
)) {
538 if (likely(child
->last_siginfo
!= NULL
)) {
539 *info
= *child
->last_siginfo
;
542 unlock_task_sighand(child
, &flags
);
547 static int ptrace_setsiginfo(struct task_struct
*child
, const siginfo_t
*info
)
552 if (lock_task_sighand(child
, &flags
)) {
554 if (likely(child
->last_siginfo
!= NULL
)) {
555 *child
->last_siginfo
= *info
;
558 unlock_task_sighand(child
, &flags
);
564 #ifdef PTRACE_SINGLESTEP
565 #define is_singlestep(request) ((request) == PTRACE_SINGLESTEP)
567 #define is_singlestep(request) 0
570 #ifdef PTRACE_SINGLEBLOCK
571 #define is_singleblock(request) ((request) == PTRACE_SINGLEBLOCK)
573 #define is_singleblock(request) 0
577 #define is_sysemu_singlestep(request) ((request) == PTRACE_SYSEMU_SINGLESTEP)
579 #define is_sysemu_singlestep(request) 0
582 static int ptrace_resume(struct task_struct
*child
, long request
,
585 if (!valid_signal(data
))
588 if (request
== PTRACE_SYSCALL
)
589 set_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
591 clear_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
593 #ifdef TIF_SYSCALL_EMU
594 if (request
== PTRACE_SYSEMU
|| request
== PTRACE_SYSEMU_SINGLESTEP
)
595 set_tsk_thread_flag(child
, TIF_SYSCALL_EMU
);
597 clear_tsk_thread_flag(child
, TIF_SYSCALL_EMU
);
600 if (is_singleblock(request
)) {
601 if (unlikely(!arch_has_block_step()))
603 user_enable_block_step(child
);
604 } else if (is_singlestep(request
) || is_sysemu_singlestep(request
)) {
605 if (unlikely(!arch_has_single_step()))
607 user_enable_single_step(child
);
609 user_disable_single_step(child
);
612 child
->exit_code
= data
;
613 wake_up_state(child
, __TASK_TRACED
);
618 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
620 static const struct user_regset
*
621 find_regset(const struct user_regset_view
*view
, unsigned int type
)
623 const struct user_regset
*regset
;
626 for (n
= 0; n
< view
->n
; ++n
) {
627 regset
= view
->regsets
+ n
;
628 if (regset
->core_note_type
== type
)
635 static int ptrace_regset(struct task_struct
*task
, int req
, unsigned int type
,
638 const struct user_regset_view
*view
= task_user_regset_view(task
);
639 const struct user_regset
*regset
= find_regset(view
, type
);
642 if (!regset
|| (kiov
->iov_len
% regset
->size
) != 0)
645 regset_no
= regset
- view
->regsets
;
646 kiov
->iov_len
= min(kiov
->iov_len
,
647 (__kernel_size_t
) (regset
->n
* regset
->size
));
649 if (req
== PTRACE_GETREGSET
)
650 return copy_regset_to_user(task
, view
, regset_no
, 0,
651 kiov
->iov_len
, kiov
->iov_base
);
653 return copy_regset_from_user(task
, view
, regset_no
, 0,
654 kiov
->iov_len
, kiov
->iov_base
);
659 int ptrace_request(struct task_struct
*child
, long request
,
660 unsigned long addr
, unsigned long data
)
662 bool seized
= child
->ptrace
& PT_SEIZED
;
664 siginfo_t siginfo
, *si
;
665 void __user
*datavp
= (void __user
*) data
;
666 unsigned long __user
*datalp
= datavp
;
670 case PTRACE_PEEKTEXT
:
671 case PTRACE_PEEKDATA
:
672 return generic_ptrace_peekdata(child
, addr
, data
);
673 case PTRACE_POKETEXT
:
674 case PTRACE_POKEDATA
:
675 return generic_ptrace_pokedata(child
, addr
, data
);
677 #ifdef PTRACE_OLDSETOPTIONS
678 case PTRACE_OLDSETOPTIONS
:
680 case PTRACE_SETOPTIONS
:
681 ret
= ptrace_setoptions(child
, data
);
683 case PTRACE_GETEVENTMSG
:
684 ret
= put_user(child
->ptrace_message
, datalp
);
687 case PTRACE_GETSIGINFO
:
688 ret
= ptrace_getsiginfo(child
, &siginfo
);
690 ret
= copy_siginfo_to_user(datavp
, &siginfo
);
693 case PTRACE_SETSIGINFO
:
694 if (copy_from_user(&siginfo
, datavp
, sizeof siginfo
))
697 ret
= ptrace_setsiginfo(child
, &siginfo
);
700 case PTRACE_INTERRUPT
:
702 * Stop tracee without any side-effect on signal or job
703 * control. At least one trap is guaranteed to happen
704 * after this request. If @child is already trapped, the
705 * current trap is not disturbed and another trap will
706 * happen after the current trap is ended with PTRACE_CONT.
708 * The actual trap might not be PTRACE_EVENT_STOP trap but
709 * the pending condition is cleared regardless.
711 if (unlikely(!seized
|| !lock_task_sighand(child
, &flags
)))
715 * INTERRUPT doesn't disturb existing trap sans one
716 * exception. If ptracer issued LISTEN for the current
717 * STOP, this INTERRUPT should clear LISTEN and re-trap
720 if (likely(task_set_jobctl_pending(child
, JOBCTL_TRAP_STOP
)))
721 signal_wake_up(child
, child
->jobctl
& JOBCTL_LISTENING
);
723 unlock_task_sighand(child
, &flags
);
729 * Listen for events. Tracee must be in STOP. It's not
730 * resumed per-se but is not considered to be in TRACED by
731 * wait(2) or ptrace(2). If an async event (e.g. group
732 * stop state change) happens, tracee will enter STOP trap
733 * again. Alternatively, ptracer can issue INTERRUPT to
734 * finish listening and re-trap tracee into STOP.
736 if (unlikely(!seized
|| !lock_task_sighand(child
, &flags
)))
739 si
= child
->last_siginfo
;
740 if (unlikely(!si
|| si
->si_code
>> 8 != PTRACE_EVENT_STOP
))
743 child
->jobctl
|= JOBCTL_LISTENING
;
746 * If NOTIFY is set, it means event happened between start
747 * of this trap and now. Trigger re-trap immediately.
749 if (child
->jobctl
& JOBCTL_TRAP_NOTIFY
)
750 signal_wake_up(child
, true);
752 unlock_task_sighand(child
, &flags
);
756 case PTRACE_DETACH
: /* detach a process that was attached. */
757 ret
= ptrace_detach(child
, data
);
760 #ifdef CONFIG_BINFMT_ELF_FDPIC
761 case PTRACE_GETFDPIC
: {
762 struct mm_struct
*mm
= get_task_mm(child
);
763 unsigned long tmp
= 0;
770 case PTRACE_GETFDPIC_EXEC
:
771 tmp
= mm
->context
.exec_fdpic_loadmap
;
773 case PTRACE_GETFDPIC_INTERP
:
774 tmp
= mm
->context
.interp_fdpic_loadmap
;
781 ret
= put_user(tmp
, datalp
);
786 #ifdef PTRACE_SINGLESTEP
787 case PTRACE_SINGLESTEP
:
789 #ifdef PTRACE_SINGLEBLOCK
790 case PTRACE_SINGLEBLOCK
:
794 case PTRACE_SYSEMU_SINGLESTEP
:
798 return ptrace_resume(child
, request
, data
);
801 if (child
->exit_state
) /* already dead */
803 return ptrace_resume(child
, request
, SIGKILL
);
805 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
806 case PTRACE_GETREGSET
:
807 case PTRACE_SETREGSET
:
810 struct iovec __user
*uiov
= datavp
;
812 if (!access_ok(VERIFY_WRITE
, uiov
, sizeof(*uiov
)))
815 if (__get_user(kiov
.iov_base
, &uiov
->iov_base
) ||
816 __get_user(kiov
.iov_len
, &uiov
->iov_len
))
819 ret
= ptrace_regset(child
, request
, addr
, &kiov
);
821 ret
= __put_user(kiov
.iov_len
, &uiov
->iov_len
);
832 static struct task_struct
*ptrace_get_task_struct(pid_t pid
)
834 struct task_struct
*child
;
837 child
= find_task_by_vpid(pid
);
839 get_task_struct(child
);
843 return ERR_PTR(-ESRCH
);
847 #ifndef arch_ptrace_attach
848 #define arch_ptrace_attach(child) do { } while (0)
851 SYSCALL_DEFINE4(ptrace
, long, request
, long, pid
, unsigned long, addr
,
854 struct task_struct
*child
;
857 if (request
== PTRACE_TRACEME
) {
858 ret
= ptrace_traceme();
860 arch_ptrace_attach(current
);
864 child
= ptrace_get_task_struct(pid
);
866 ret
= PTR_ERR(child
);
870 if (request
== PTRACE_ATTACH
|| request
== PTRACE_SEIZE
) {
871 ret
= ptrace_attach(child
, request
, data
);
873 * Some architectures need to do book-keeping after
877 arch_ptrace_attach(child
);
878 goto out_put_task_struct
;
881 ret
= ptrace_check_attach(child
, request
== PTRACE_KILL
||
882 request
== PTRACE_INTERRUPT
);
884 goto out_put_task_struct
;
886 ret
= arch_ptrace(child
, request
, addr
, data
);
889 put_task_struct(child
);
894 int generic_ptrace_peekdata(struct task_struct
*tsk
, unsigned long addr
,
900 copied
= access_process_vm(tsk
, addr
, &tmp
, sizeof(tmp
), 0);
901 if (copied
!= sizeof(tmp
))
903 return put_user(tmp
, (unsigned long __user
*)data
);
906 int generic_ptrace_pokedata(struct task_struct
*tsk
, unsigned long addr
,
911 copied
= access_process_vm(tsk
, addr
, &data
, sizeof(data
), 1);
912 return (copied
== sizeof(data
)) ? 0 : -EIO
;
915 #if defined CONFIG_COMPAT
916 #include <linux/compat.h>
918 int compat_ptrace_request(struct task_struct
*child
, compat_long_t request
,
919 compat_ulong_t addr
, compat_ulong_t data
)
921 compat_ulong_t __user
*datap
= compat_ptr(data
);
927 case PTRACE_PEEKTEXT
:
928 case PTRACE_PEEKDATA
:
929 ret
= access_process_vm(child
, addr
, &word
, sizeof(word
), 0);
930 if (ret
!= sizeof(word
))
933 ret
= put_user(word
, datap
);
936 case PTRACE_POKETEXT
:
937 case PTRACE_POKEDATA
:
938 ret
= access_process_vm(child
, addr
, &data
, sizeof(data
), 1);
939 ret
= (ret
!= sizeof(data
) ? -EIO
: 0);
942 case PTRACE_GETEVENTMSG
:
943 ret
= put_user((compat_ulong_t
) child
->ptrace_message
, datap
);
946 case PTRACE_GETSIGINFO
:
947 ret
= ptrace_getsiginfo(child
, &siginfo
);
949 ret
= copy_siginfo_to_user32(
950 (struct compat_siginfo __user
*) datap
,
954 case PTRACE_SETSIGINFO
:
955 memset(&siginfo
, 0, sizeof siginfo
);
956 if (copy_siginfo_from_user32(
957 &siginfo
, (struct compat_siginfo __user
*) datap
))
960 ret
= ptrace_setsiginfo(child
, &siginfo
);
962 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
963 case PTRACE_GETREGSET
:
964 case PTRACE_SETREGSET
:
967 struct compat_iovec __user
*uiov
=
968 (struct compat_iovec __user
*) datap
;
972 if (!access_ok(VERIFY_WRITE
, uiov
, sizeof(*uiov
)))
975 if (__get_user(ptr
, &uiov
->iov_base
) ||
976 __get_user(len
, &uiov
->iov_len
))
979 kiov
.iov_base
= compat_ptr(ptr
);
982 ret
= ptrace_regset(child
, request
, addr
, &kiov
);
984 ret
= __put_user(kiov
.iov_len
, &uiov
->iov_len
);
990 ret
= ptrace_request(child
, request
, addr
, data
);
996 asmlinkage
long compat_sys_ptrace(compat_long_t request
, compat_long_t pid
,
997 compat_long_t addr
, compat_long_t data
)
999 struct task_struct
*child
;
1002 if (request
== PTRACE_TRACEME
) {
1003 ret
= ptrace_traceme();
1007 child
= ptrace_get_task_struct(pid
);
1008 if (IS_ERR(child
)) {
1009 ret
= PTR_ERR(child
);
1013 if (request
== PTRACE_ATTACH
|| request
== PTRACE_SEIZE
) {
1014 ret
= ptrace_attach(child
, request
, data
);
1016 * Some architectures need to do book-keeping after
1020 arch_ptrace_attach(child
);
1021 goto out_put_task_struct
;
1024 ret
= ptrace_check_attach(child
, request
== PTRACE_KILL
||
1025 request
== PTRACE_INTERRUPT
);
1027 ret
= compat_arch_ptrace(child
, request
, addr
, data
);
1029 out_put_task_struct
:
1030 put_task_struct(child
);
1034 #endif /* CONFIG_COMPAT */
1036 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1037 int ptrace_get_breakpoints(struct task_struct
*tsk
)
1039 if (atomic_inc_not_zero(&tsk
->ptrace_bp_refcnt
))
1045 void ptrace_put_breakpoints(struct task_struct
*tsk
)
1047 if (atomic_dec_and_test(&tsk
->ptrace_bp_refcnt
))
1048 flush_ptrace_hw_breakpoint(tsk
);
1050 #endif /* CONFIG_HAVE_HW_BREAKPOINT */