]>
git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blob - kernel/ptrace.c
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 (uid_eq(cred
->uid
, tcred
->euid
) &&
202 uid_eq(cred
->uid
, tcred
->suid
) &&
203 uid_eq(cred
->uid
, tcred
->uid
) &&
204 gid_eq(cred
->gid
, tcred
->egid
) &&
205 gid_eq(cred
->gid
, tcred
->sgid
) &&
206 gid_eq(cred
->gid
, tcred
->gid
))
208 if (ptrace_has_cap(tcred
->user_ns
, mode
))
216 dumpable
= get_dumpable(task
->mm
);
217 if (!dumpable
&& !ptrace_has_cap(task_user_ns(task
), mode
))
220 return security_ptrace_access_check(task
, mode
);
223 bool ptrace_may_access(struct task_struct
*task
, unsigned int mode
)
227 err
= __ptrace_may_access(task
, mode
);
232 static int ptrace_attach(struct task_struct
*task
, long request
,
236 bool seize
= (request
== PTRACE_SEIZE
);
243 if (flags
& ~(unsigned long)PTRACE_O_MASK
)
245 flags
= PT_PTRACED
| PT_SEIZED
| (flags
<< PT_OPT_FLAG_SHIFT
);
253 if (unlikely(task
->flags
& PF_KTHREAD
))
255 if (same_thread_group(task
, current
))
259 * Protect exec's credential calculations against our interference;
260 * SUID, SGID and LSM creds get determined differently
263 retval
= -ERESTARTNOINTR
;
264 if (mutex_lock_interruptible(&task
->signal
->cred_guard_mutex
))
268 retval
= __ptrace_may_access(task
, PTRACE_MODE_ATTACH
);
273 write_lock_irq(&tasklist_lock
);
275 if (unlikely(task
->exit_state
))
276 goto unlock_tasklist
;
278 goto unlock_tasklist
;
282 if (ns_capable(task_user_ns(task
), CAP_SYS_PTRACE
))
283 flags
|= PT_PTRACE_CAP
;
284 task
->ptrace
= flags
;
286 __ptrace_link(task
, current
);
288 /* SEIZE doesn't trap tracee on attach */
290 send_sig_info(SIGSTOP
, SEND_SIG_FORCED
, task
);
292 spin_lock(&task
->sighand
->siglock
);
295 * If the task is already STOPPED, set JOBCTL_TRAP_STOP and
296 * TRAPPING, and kick it so that it transits to TRACED. TRAPPING
297 * will be cleared if the child completes the transition or any
298 * event which clears the group stop states happens. We'll wait
299 * for the transition to complete before returning from this
302 * This hides STOPPED -> RUNNING -> TRACED transition from the
303 * attaching thread but a different thread in the same group can
304 * still observe the transient RUNNING state. IOW, if another
305 * thread's WNOHANG wait(2) on the stopped tracee races against
306 * ATTACH, the wait(2) may fail due to the transient RUNNING.
308 * The following task_is_stopped() test is safe as both transitions
309 * in and out of STOPPED are protected by siglock.
311 if (task_is_stopped(task
) &&
312 task_set_jobctl_pending(task
, JOBCTL_TRAP_STOP
| JOBCTL_TRAPPING
))
313 signal_wake_up(task
, 1);
315 spin_unlock(&task
->sighand
->siglock
);
319 write_unlock_irq(&tasklist_lock
);
321 mutex_unlock(&task
->signal
->cred_guard_mutex
);
324 wait_on_bit(&task
->jobctl
, JOBCTL_TRAPPING_BIT
,
325 ptrace_trapping_sleep_fn
, TASK_UNINTERRUPTIBLE
);
326 proc_ptrace_connector(task
, PTRACE_ATTACH
);
333 * ptrace_traceme -- helper for PTRACE_TRACEME
335 * Performs checks and sets PT_PTRACED.
336 * Should be used by all ptrace implementations for PTRACE_TRACEME.
338 static int ptrace_traceme(void)
342 write_lock_irq(&tasklist_lock
);
343 /* Are we already being traced? */
344 if (!current
->ptrace
) {
345 ret
= security_ptrace_traceme(current
->parent
);
347 * Check PF_EXITING to ensure ->real_parent has not passed
348 * exit_ptrace(). Otherwise we don't report the error but
349 * pretend ->real_parent untraces us right after return.
351 if (!ret
&& !(current
->real_parent
->flags
& PF_EXITING
)) {
352 current
->ptrace
= PT_PTRACED
;
353 __ptrace_link(current
, current
->real_parent
);
356 write_unlock_irq(&tasklist_lock
);
362 * Called with irqs disabled, returns true if childs should reap themselves.
364 static int ignoring_children(struct sighand_struct
*sigh
)
367 spin_lock(&sigh
->siglock
);
368 ret
= (sigh
->action
[SIGCHLD
-1].sa
.sa_handler
== SIG_IGN
) ||
369 (sigh
->action
[SIGCHLD
-1].sa
.sa_flags
& SA_NOCLDWAIT
);
370 spin_unlock(&sigh
->siglock
);
375 * Called with tasklist_lock held for writing.
376 * Unlink a traced task, and clean it up if it was a traced zombie.
377 * Return true if it needs to be reaped with release_task().
378 * (We can't call release_task() here because we already hold tasklist_lock.)
380 * If it's a zombie, our attachedness prevented normal parent notification
381 * or self-reaping. Do notification now if it would have happened earlier.
382 * If it should reap itself, return true.
384 * If it's our own child, there is no notification to do. But if our normal
385 * children self-reap, then this child was prevented by ptrace and we must
386 * reap it now, in that case we must also wake up sub-threads sleeping in
389 static bool __ptrace_detach(struct task_struct
*tracer
, struct task_struct
*p
)
395 if (p
->exit_state
!= EXIT_ZOMBIE
)
398 dead
= !thread_group_leader(p
);
400 if (!dead
&& thread_group_empty(p
)) {
401 if (!same_thread_group(p
->real_parent
, tracer
))
402 dead
= do_notify_parent(p
, p
->exit_signal
);
403 else if (ignoring_children(tracer
->sighand
)) {
404 __wake_up_parent(p
, tracer
);
408 /* Mark it as in the process of being reaped. */
410 p
->exit_state
= EXIT_DEAD
;
414 static int ptrace_detach(struct task_struct
*child
, unsigned int data
)
418 if (!valid_signal(data
))
421 /* Architecture-specific hardware disable .. */
422 ptrace_disable(child
);
423 clear_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
425 write_lock_irq(&tasklist_lock
);
427 * This child can be already killed. Make sure de_thread() or
428 * our sub-thread doing do_wait() didn't do release_task() yet.
431 child
->exit_code
= data
;
432 dead
= __ptrace_detach(current
, child
);
434 write_unlock_irq(&tasklist_lock
);
436 proc_ptrace_connector(child
, PTRACE_DETACH
);
444 * Detach all tasks we were using ptrace on. Called with tasklist held
445 * for writing, and returns with it held too. But note it can release
446 * and reacquire the lock.
448 void exit_ptrace(struct task_struct
*tracer
)
449 __releases(&tasklist_lock
)
450 __acquires(&tasklist_lock
)
452 struct task_struct
*p
, *n
;
453 LIST_HEAD(ptrace_dead
);
455 if (likely(list_empty(&tracer
->ptraced
)))
458 list_for_each_entry_safe(p
, n
, &tracer
->ptraced
, ptrace_entry
) {
459 if (__ptrace_detach(tracer
, p
))
460 list_add(&p
->ptrace_entry
, &ptrace_dead
);
463 write_unlock_irq(&tasklist_lock
);
464 BUG_ON(!list_empty(&tracer
->ptraced
));
466 list_for_each_entry_safe(p
, n
, &ptrace_dead
, ptrace_entry
) {
467 list_del_init(&p
->ptrace_entry
);
471 write_lock_irq(&tasklist_lock
);
474 int ptrace_readdata(struct task_struct
*tsk
, unsigned long src
, char __user
*dst
, int len
)
480 int this_len
, retval
;
482 this_len
= (len
> sizeof(buf
)) ? sizeof(buf
) : len
;
483 retval
= access_process_vm(tsk
, src
, buf
, this_len
, 0);
489 if (copy_to_user(dst
, buf
, retval
))
499 int ptrace_writedata(struct task_struct
*tsk
, char __user
*src
, unsigned long dst
, int len
)
505 int this_len
, retval
;
507 this_len
= (len
> sizeof(buf
)) ? sizeof(buf
) : len
;
508 if (copy_from_user(buf
, src
, this_len
))
510 retval
= access_process_vm(tsk
, dst
, buf
, this_len
, 1);
524 static int ptrace_setoptions(struct task_struct
*child
, unsigned long data
)
528 if (data
& ~(unsigned long)PTRACE_O_MASK
)
531 /* Avoid intermediate state when all opts are cleared */
532 flags
= child
->ptrace
;
533 flags
&= ~(PTRACE_O_MASK
<< PT_OPT_FLAG_SHIFT
);
534 flags
|= (data
<< PT_OPT_FLAG_SHIFT
);
535 child
->ptrace
= flags
;
540 static int ptrace_getsiginfo(struct task_struct
*child
, siginfo_t
*info
)
545 if (lock_task_sighand(child
, &flags
)) {
547 if (likely(child
->last_siginfo
!= NULL
)) {
548 *info
= *child
->last_siginfo
;
551 unlock_task_sighand(child
, &flags
);
556 static int ptrace_setsiginfo(struct task_struct
*child
, const siginfo_t
*info
)
561 if (lock_task_sighand(child
, &flags
)) {
563 if (likely(child
->last_siginfo
!= NULL
)) {
564 *child
->last_siginfo
= *info
;
567 unlock_task_sighand(child
, &flags
);
573 #ifdef PTRACE_SINGLESTEP
574 #define is_singlestep(request) ((request) == PTRACE_SINGLESTEP)
576 #define is_singlestep(request) 0
579 #ifdef PTRACE_SINGLEBLOCK
580 #define is_singleblock(request) ((request) == PTRACE_SINGLEBLOCK)
582 #define is_singleblock(request) 0
586 #define is_sysemu_singlestep(request) ((request) == PTRACE_SYSEMU_SINGLESTEP)
588 #define is_sysemu_singlestep(request) 0
591 static int ptrace_resume(struct task_struct
*child
, long request
,
594 if (!valid_signal(data
))
597 if (request
== PTRACE_SYSCALL
)
598 set_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
600 clear_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
602 #ifdef TIF_SYSCALL_EMU
603 if (request
== PTRACE_SYSEMU
|| request
== PTRACE_SYSEMU_SINGLESTEP
)
604 set_tsk_thread_flag(child
, TIF_SYSCALL_EMU
);
606 clear_tsk_thread_flag(child
, TIF_SYSCALL_EMU
);
609 if (is_singleblock(request
)) {
610 if (unlikely(!arch_has_block_step()))
612 user_enable_block_step(child
);
613 } else if (is_singlestep(request
) || is_sysemu_singlestep(request
)) {
614 if (unlikely(!arch_has_single_step()))
616 user_enable_single_step(child
);
618 user_disable_single_step(child
);
621 child
->exit_code
= data
;
622 wake_up_state(child
, __TASK_TRACED
);
627 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
629 static const struct user_regset
*
630 find_regset(const struct user_regset_view
*view
, unsigned int type
)
632 const struct user_regset
*regset
;
635 for (n
= 0; n
< view
->n
; ++n
) {
636 regset
= view
->regsets
+ n
;
637 if (regset
->core_note_type
== type
)
644 static int ptrace_regset(struct task_struct
*task
, int req
, unsigned int type
,
647 const struct user_regset_view
*view
= task_user_regset_view(task
);
648 const struct user_regset
*regset
= find_regset(view
, type
);
651 if (!regset
|| (kiov
->iov_len
% regset
->size
) != 0)
654 regset_no
= regset
- view
->regsets
;
655 kiov
->iov_len
= min(kiov
->iov_len
,
656 (__kernel_size_t
) (regset
->n
* regset
->size
));
658 if (req
== PTRACE_GETREGSET
)
659 return copy_regset_to_user(task
, view
, regset_no
, 0,
660 kiov
->iov_len
, kiov
->iov_base
);
662 return copy_regset_from_user(task
, view
, regset_no
, 0,
663 kiov
->iov_len
, kiov
->iov_base
);
668 int ptrace_request(struct task_struct
*child
, long request
,
669 unsigned long addr
, unsigned long data
)
671 bool seized
= child
->ptrace
& PT_SEIZED
;
673 siginfo_t siginfo
, *si
;
674 void __user
*datavp
= (void __user
*) data
;
675 unsigned long __user
*datalp
= datavp
;
679 case PTRACE_PEEKTEXT
:
680 case PTRACE_PEEKDATA
:
681 return generic_ptrace_peekdata(child
, addr
, data
);
682 case PTRACE_POKETEXT
:
683 case PTRACE_POKEDATA
:
684 return generic_ptrace_pokedata(child
, addr
, data
);
686 #ifdef PTRACE_OLDSETOPTIONS
687 case PTRACE_OLDSETOPTIONS
:
689 case PTRACE_SETOPTIONS
:
690 ret
= ptrace_setoptions(child
, data
);
692 case PTRACE_GETEVENTMSG
:
693 ret
= put_user(child
->ptrace_message
, datalp
);
696 case PTRACE_GETSIGINFO
:
697 ret
= ptrace_getsiginfo(child
, &siginfo
);
699 ret
= copy_siginfo_to_user(datavp
, &siginfo
);
702 case PTRACE_SETSIGINFO
:
703 if (copy_from_user(&siginfo
, datavp
, sizeof siginfo
))
706 ret
= ptrace_setsiginfo(child
, &siginfo
);
709 case PTRACE_INTERRUPT
:
711 * Stop tracee without any side-effect on signal or job
712 * control. At least one trap is guaranteed to happen
713 * after this request. If @child is already trapped, the
714 * current trap is not disturbed and another trap will
715 * happen after the current trap is ended with PTRACE_CONT.
717 * The actual trap might not be PTRACE_EVENT_STOP trap but
718 * the pending condition is cleared regardless.
720 if (unlikely(!seized
|| !lock_task_sighand(child
, &flags
)))
724 * INTERRUPT doesn't disturb existing trap sans one
725 * exception. If ptracer issued LISTEN for the current
726 * STOP, this INTERRUPT should clear LISTEN and re-trap
729 if (likely(task_set_jobctl_pending(child
, JOBCTL_TRAP_STOP
)))
730 signal_wake_up(child
, child
->jobctl
& JOBCTL_LISTENING
);
732 unlock_task_sighand(child
, &flags
);
738 * Listen for events. Tracee must be in STOP. It's not
739 * resumed per-se but is not considered to be in TRACED by
740 * wait(2) or ptrace(2). If an async event (e.g. group
741 * stop state change) happens, tracee will enter STOP trap
742 * again. Alternatively, ptracer can issue INTERRUPT to
743 * finish listening and re-trap tracee into STOP.
745 if (unlikely(!seized
|| !lock_task_sighand(child
, &flags
)))
748 si
= child
->last_siginfo
;
749 if (likely(si
&& (si
->si_code
>> 8) == PTRACE_EVENT_STOP
)) {
750 child
->jobctl
|= JOBCTL_LISTENING
;
752 * If NOTIFY is set, it means event happened between
753 * start of this trap and now. Trigger re-trap.
755 if (child
->jobctl
& JOBCTL_TRAP_NOTIFY
)
756 signal_wake_up(child
, true);
759 unlock_task_sighand(child
, &flags
);
762 case PTRACE_DETACH
: /* detach a process that was attached. */
763 ret
= ptrace_detach(child
, data
);
766 #ifdef CONFIG_BINFMT_ELF_FDPIC
767 case PTRACE_GETFDPIC
: {
768 struct mm_struct
*mm
= get_task_mm(child
);
769 unsigned long tmp
= 0;
776 case PTRACE_GETFDPIC_EXEC
:
777 tmp
= mm
->context
.exec_fdpic_loadmap
;
779 case PTRACE_GETFDPIC_INTERP
:
780 tmp
= mm
->context
.interp_fdpic_loadmap
;
787 ret
= put_user(tmp
, datalp
);
792 #ifdef PTRACE_SINGLESTEP
793 case PTRACE_SINGLESTEP
:
795 #ifdef PTRACE_SINGLEBLOCK
796 case PTRACE_SINGLEBLOCK
:
800 case PTRACE_SYSEMU_SINGLESTEP
:
804 return ptrace_resume(child
, request
, data
);
807 if (child
->exit_state
) /* already dead */
809 return ptrace_resume(child
, request
, SIGKILL
);
811 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
812 case PTRACE_GETREGSET
:
813 case PTRACE_SETREGSET
:
816 struct iovec __user
*uiov
= datavp
;
818 if (!access_ok(VERIFY_WRITE
, uiov
, sizeof(*uiov
)))
821 if (__get_user(kiov
.iov_base
, &uiov
->iov_base
) ||
822 __get_user(kiov
.iov_len
, &uiov
->iov_len
))
825 ret
= ptrace_regset(child
, request
, addr
, &kiov
);
827 ret
= __put_user(kiov
.iov_len
, &uiov
->iov_len
);
838 static struct task_struct
*ptrace_get_task_struct(pid_t pid
)
840 struct task_struct
*child
;
843 child
= find_task_by_vpid(pid
);
845 get_task_struct(child
);
849 return ERR_PTR(-ESRCH
);
853 #ifndef arch_ptrace_attach
854 #define arch_ptrace_attach(child) do { } while (0)
857 SYSCALL_DEFINE4(ptrace
, long, request
, long, pid
, unsigned long, addr
,
860 struct task_struct
*child
;
863 if (request
== PTRACE_TRACEME
) {
864 ret
= ptrace_traceme();
866 arch_ptrace_attach(current
);
870 child
= ptrace_get_task_struct(pid
);
872 ret
= PTR_ERR(child
);
876 if (request
== PTRACE_ATTACH
|| request
== PTRACE_SEIZE
) {
877 ret
= ptrace_attach(child
, request
, addr
, data
);
879 * Some architectures need to do book-keeping after
883 arch_ptrace_attach(child
);
884 goto out_put_task_struct
;
887 ret
= ptrace_check_attach(child
, request
== PTRACE_KILL
||
888 request
== PTRACE_INTERRUPT
);
890 goto out_put_task_struct
;
892 ret
= arch_ptrace(child
, request
, addr
, data
);
895 put_task_struct(child
);
900 int generic_ptrace_peekdata(struct task_struct
*tsk
, unsigned long addr
,
906 copied
= access_process_vm(tsk
, addr
, &tmp
, sizeof(tmp
), 0);
907 if (copied
!= sizeof(tmp
))
909 return put_user(tmp
, (unsigned long __user
*)data
);
912 int generic_ptrace_pokedata(struct task_struct
*tsk
, unsigned long addr
,
917 copied
= access_process_vm(tsk
, addr
, &data
, sizeof(data
), 1);
918 return (copied
== sizeof(data
)) ? 0 : -EIO
;
921 #if defined CONFIG_COMPAT
922 #include <linux/compat.h>
924 int compat_ptrace_request(struct task_struct
*child
, compat_long_t request
,
925 compat_ulong_t addr
, compat_ulong_t data
)
927 compat_ulong_t __user
*datap
= compat_ptr(data
);
933 case PTRACE_PEEKTEXT
:
934 case PTRACE_PEEKDATA
:
935 ret
= access_process_vm(child
, addr
, &word
, sizeof(word
), 0);
936 if (ret
!= sizeof(word
))
939 ret
= put_user(word
, datap
);
942 case PTRACE_POKETEXT
:
943 case PTRACE_POKEDATA
:
944 ret
= access_process_vm(child
, addr
, &data
, sizeof(data
), 1);
945 ret
= (ret
!= sizeof(data
) ? -EIO
: 0);
948 case PTRACE_GETEVENTMSG
:
949 ret
= put_user((compat_ulong_t
) child
->ptrace_message
, datap
);
952 case PTRACE_GETSIGINFO
:
953 ret
= ptrace_getsiginfo(child
, &siginfo
);
955 ret
= copy_siginfo_to_user32(
956 (struct compat_siginfo __user
*) datap
,
960 case PTRACE_SETSIGINFO
:
961 memset(&siginfo
, 0, sizeof siginfo
);
962 if (copy_siginfo_from_user32(
963 &siginfo
, (struct compat_siginfo __user
*) datap
))
966 ret
= ptrace_setsiginfo(child
, &siginfo
);
968 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
969 case PTRACE_GETREGSET
:
970 case PTRACE_SETREGSET
:
973 struct compat_iovec __user
*uiov
=
974 (struct compat_iovec __user
*) datap
;
978 if (!access_ok(VERIFY_WRITE
, uiov
, sizeof(*uiov
)))
981 if (__get_user(ptr
, &uiov
->iov_base
) ||
982 __get_user(len
, &uiov
->iov_len
))
985 kiov
.iov_base
= compat_ptr(ptr
);
988 ret
= ptrace_regset(child
, request
, addr
, &kiov
);
990 ret
= __put_user(kiov
.iov_len
, &uiov
->iov_len
);
996 ret
= ptrace_request(child
, request
, addr
, data
);
1002 asmlinkage
long compat_sys_ptrace(compat_long_t request
, compat_long_t pid
,
1003 compat_long_t addr
, compat_long_t data
)
1005 struct task_struct
*child
;
1008 if (request
== PTRACE_TRACEME
) {
1009 ret
= ptrace_traceme();
1013 child
= ptrace_get_task_struct(pid
);
1014 if (IS_ERR(child
)) {
1015 ret
= PTR_ERR(child
);
1019 if (request
== PTRACE_ATTACH
|| request
== PTRACE_SEIZE
) {
1020 ret
= ptrace_attach(child
, request
, addr
, data
);
1022 * Some architectures need to do book-keeping after
1026 arch_ptrace_attach(child
);
1027 goto out_put_task_struct
;
1030 ret
= ptrace_check_attach(child
, request
== PTRACE_KILL
||
1031 request
== PTRACE_INTERRUPT
);
1033 ret
= compat_arch_ptrace(child
, request
, addr
, data
);
1035 out_put_task_struct
:
1036 put_task_struct(child
);
1040 #endif /* CONFIG_COMPAT */
1042 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1043 int ptrace_get_breakpoints(struct task_struct
*tsk
)
1045 if (atomic_inc_not_zero(&tsk
->ptrace_bp_refcnt
))
1051 void ptrace_put_breakpoints(struct task_struct
*tsk
)
1053 if (atomic_dec_and_test(&tsk
->ptrace_bp_refcnt
))
1054 flush_ptrace_hw_breakpoint(tsk
);
1056 #endif /* CONFIG_HAVE_HW_BREAKPOINT */