]>
git.proxmox.com Git - mirror_ubuntu-jammy-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 (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 child
->ptrace
&= ~PT_TRACE_MASK
;
533 if (data
& PTRACE_O_TRACESYSGOOD
)
534 child
->ptrace
|= PT_TRACESYSGOOD
;
536 if (data
& PTRACE_O_TRACEFORK
)
537 child
->ptrace
|= PT_TRACE_FORK
;
539 if (data
& PTRACE_O_TRACEVFORK
)
540 child
->ptrace
|= PT_TRACE_VFORK
;
542 if (data
& PTRACE_O_TRACECLONE
)
543 child
->ptrace
|= PT_TRACE_CLONE
;
545 if (data
& PTRACE_O_TRACEEXEC
)
546 child
->ptrace
|= PT_TRACE_EXEC
;
548 if (data
& PTRACE_O_TRACEVFORKDONE
)
549 child
->ptrace
|= PT_TRACE_VFORK_DONE
;
551 if (data
& PTRACE_O_TRACEEXIT
)
552 child
->ptrace
|= PT_TRACE_EXIT
;
554 return (data
& ~PTRACE_O_MASK
) ? -EINVAL
: 0;
557 static int ptrace_getsiginfo(struct task_struct
*child
, siginfo_t
*info
)
562 if (lock_task_sighand(child
, &flags
)) {
564 if (likely(child
->last_siginfo
!= NULL
)) {
565 *info
= *child
->last_siginfo
;
568 unlock_task_sighand(child
, &flags
);
573 static int ptrace_setsiginfo(struct task_struct
*child
, const siginfo_t
*info
)
578 if (lock_task_sighand(child
, &flags
)) {
580 if (likely(child
->last_siginfo
!= NULL
)) {
581 *child
->last_siginfo
= *info
;
584 unlock_task_sighand(child
, &flags
);
590 #ifdef PTRACE_SINGLESTEP
591 #define is_singlestep(request) ((request) == PTRACE_SINGLESTEP)
593 #define is_singlestep(request) 0
596 #ifdef PTRACE_SINGLEBLOCK
597 #define is_singleblock(request) ((request) == PTRACE_SINGLEBLOCK)
599 #define is_singleblock(request) 0
603 #define is_sysemu_singlestep(request) ((request) == PTRACE_SYSEMU_SINGLESTEP)
605 #define is_sysemu_singlestep(request) 0
608 static int ptrace_resume(struct task_struct
*child
, long request
,
611 if (!valid_signal(data
))
614 if (request
== PTRACE_SYSCALL
)
615 set_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
617 clear_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
619 #ifdef TIF_SYSCALL_EMU
620 if (request
== PTRACE_SYSEMU
|| request
== PTRACE_SYSEMU_SINGLESTEP
)
621 set_tsk_thread_flag(child
, TIF_SYSCALL_EMU
);
623 clear_tsk_thread_flag(child
, TIF_SYSCALL_EMU
);
626 if (is_singleblock(request
)) {
627 if (unlikely(!arch_has_block_step()))
629 user_enable_block_step(child
);
630 } else if (is_singlestep(request
) || is_sysemu_singlestep(request
)) {
631 if (unlikely(!arch_has_single_step()))
633 user_enable_single_step(child
);
635 user_disable_single_step(child
);
638 child
->exit_code
= data
;
639 wake_up_state(child
, __TASK_TRACED
);
644 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
646 static const struct user_regset
*
647 find_regset(const struct user_regset_view
*view
, unsigned int type
)
649 const struct user_regset
*regset
;
652 for (n
= 0; n
< view
->n
; ++n
) {
653 regset
= view
->regsets
+ n
;
654 if (regset
->core_note_type
== type
)
661 static int ptrace_regset(struct task_struct
*task
, int req
, unsigned int type
,
664 const struct user_regset_view
*view
= task_user_regset_view(task
);
665 const struct user_regset
*regset
= find_regset(view
, type
);
668 if (!regset
|| (kiov
->iov_len
% regset
->size
) != 0)
671 regset_no
= regset
- view
->regsets
;
672 kiov
->iov_len
= min(kiov
->iov_len
,
673 (__kernel_size_t
) (regset
->n
* regset
->size
));
675 if (req
== PTRACE_GETREGSET
)
676 return copy_regset_to_user(task
, view
, regset_no
, 0,
677 kiov
->iov_len
, kiov
->iov_base
);
679 return copy_regset_from_user(task
, view
, regset_no
, 0,
680 kiov
->iov_len
, kiov
->iov_base
);
685 int ptrace_request(struct task_struct
*child
, long request
,
686 unsigned long addr
, unsigned long data
)
688 bool seized
= child
->ptrace
& PT_SEIZED
;
690 siginfo_t siginfo
, *si
;
691 void __user
*datavp
= (void __user
*) data
;
692 unsigned long __user
*datalp
= datavp
;
696 case PTRACE_PEEKTEXT
:
697 case PTRACE_PEEKDATA
:
698 return generic_ptrace_peekdata(child
, addr
, data
);
699 case PTRACE_POKETEXT
:
700 case PTRACE_POKEDATA
:
701 return generic_ptrace_pokedata(child
, addr
, data
);
703 #ifdef PTRACE_OLDSETOPTIONS
704 case PTRACE_OLDSETOPTIONS
:
706 case PTRACE_SETOPTIONS
:
707 ret
= ptrace_setoptions(child
, data
);
709 case PTRACE_GETEVENTMSG
:
710 ret
= put_user(child
->ptrace_message
, datalp
);
713 case PTRACE_GETSIGINFO
:
714 ret
= ptrace_getsiginfo(child
, &siginfo
);
716 ret
= copy_siginfo_to_user(datavp
, &siginfo
);
719 case PTRACE_SETSIGINFO
:
720 if (copy_from_user(&siginfo
, datavp
, sizeof siginfo
))
723 ret
= ptrace_setsiginfo(child
, &siginfo
);
726 case PTRACE_INTERRUPT
:
728 * Stop tracee without any side-effect on signal or job
729 * control. At least one trap is guaranteed to happen
730 * after this request. If @child is already trapped, the
731 * current trap is not disturbed and another trap will
732 * happen after the current trap is ended with PTRACE_CONT.
734 * The actual trap might not be PTRACE_EVENT_STOP trap but
735 * the pending condition is cleared regardless.
737 if (unlikely(!seized
|| !lock_task_sighand(child
, &flags
)))
741 * INTERRUPT doesn't disturb existing trap sans one
742 * exception. If ptracer issued LISTEN for the current
743 * STOP, this INTERRUPT should clear LISTEN and re-trap
746 if (likely(task_set_jobctl_pending(child
, JOBCTL_TRAP_STOP
)))
747 signal_wake_up(child
, child
->jobctl
& JOBCTL_LISTENING
);
749 unlock_task_sighand(child
, &flags
);
755 * Listen for events. Tracee must be in STOP. It's not
756 * resumed per-se but is not considered to be in TRACED by
757 * wait(2) or ptrace(2). If an async event (e.g. group
758 * stop state change) happens, tracee will enter STOP trap
759 * again. Alternatively, ptracer can issue INTERRUPT to
760 * finish listening and re-trap tracee into STOP.
762 if (unlikely(!seized
|| !lock_task_sighand(child
, &flags
)))
765 si
= child
->last_siginfo
;
766 if (likely(si
&& (si
->si_code
>> 8) == PTRACE_EVENT_STOP
)) {
767 child
->jobctl
|= JOBCTL_LISTENING
;
769 * If NOTIFY is set, it means event happened between
770 * start of this trap and now. Trigger re-trap.
772 if (child
->jobctl
& JOBCTL_TRAP_NOTIFY
)
773 signal_wake_up(child
, true);
776 unlock_task_sighand(child
, &flags
);
779 case PTRACE_DETACH
: /* detach a process that was attached. */
780 ret
= ptrace_detach(child
, data
);
783 #ifdef CONFIG_BINFMT_ELF_FDPIC
784 case PTRACE_GETFDPIC
: {
785 struct mm_struct
*mm
= get_task_mm(child
);
786 unsigned long tmp
= 0;
793 case PTRACE_GETFDPIC_EXEC
:
794 tmp
= mm
->context
.exec_fdpic_loadmap
;
796 case PTRACE_GETFDPIC_INTERP
:
797 tmp
= mm
->context
.interp_fdpic_loadmap
;
804 ret
= put_user(tmp
, datalp
);
809 #ifdef PTRACE_SINGLESTEP
810 case PTRACE_SINGLESTEP
:
812 #ifdef PTRACE_SINGLEBLOCK
813 case PTRACE_SINGLEBLOCK
:
817 case PTRACE_SYSEMU_SINGLESTEP
:
821 return ptrace_resume(child
, request
, data
);
824 if (child
->exit_state
) /* already dead */
826 return ptrace_resume(child
, request
, SIGKILL
);
828 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
829 case PTRACE_GETREGSET
:
830 case PTRACE_SETREGSET
:
833 struct iovec __user
*uiov
= datavp
;
835 if (!access_ok(VERIFY_WRITE
, uiov
, sizeof(*uiov
)))
838 if (__get_user(kiov
.iov_base
, &uiov
->iov_base
) ||
839 __get_user(kiov
.iov_len
, &uiov
->iov_len
))
842 ret
= ptrace_regset(child
, request
, addr
, &kiov
);
844 ret
= __put_user(kiov
.iov_len
, &uiov
->iov_len
);
855 static struct task_struct
*ptrace_get_task_struct(pid_t pid
)
857 struct task_struct
*child
;
860 child
= find_task_by_vpid(pid
);
862 get_task_struct(child
);
866 return ERR_PTR(-ESRCH
);
870 #ifndef arch_ptrace_attach
871 #define arch_ptrace_attach(child) do { } while (0)
874 SYSCALL_DEFINE4(ptrace
, long, request
, long, pid
, unsigned long, addr
,
877 struct task_struct
*child
;
880 if (request
== PTRACE_TRACEME
) {
881 ret
= ptrace_traceme();
883 arch_ptrace_attach(current
);
887 child
= ptrace_get_task_struct(pid
);
889 ret
= PTR_ERR(child
);
893 if (request
== PTRACE_ATTACH
|| request
== PTRACE_SEIZE
) {
894 ret
= ptrace_attach(child
, request
, data
);
896 * Some architectures need to do book-keeping after
900 arch_ptrace_attach(child
);
901 goto out_put_task_struct
;
904 ret
= ptrace_check_attach(child
, request
== PTRACE_KILL
||
905 request
== PTRACE_INTERRUPT
);
907 goto out_put_task_struct
;
909 ret
= arch_ptrace(child
, request
, addr
, data
);
912 put_task_struct(child
);
917 int generic_ptrace_peekdata(struct task_struct
*tsk
, unsigned long addr
,
923 copied
= access_process_vm(tsk
, addr
, &tmp
, sizeof(tmp
), 0);
924 if (copied
!= sizeof(tmp
))
926 return put_user(tmp
, (unsigned long __user
*)data
);
929 int generic_ptrace_pokedata(struct task_struct
*tsk
, unsigned long addr
,
934 copied
= access_process_vm(tsk
, addr
, &data
, sizeof(data
), 1);
935 return (copied
== sizeof(data
)) ? 0 : -EIO
;
938 #if defined CONFIG_COMPAT
939 #include <linux/compat.h>
941 int compat_ptrace_request(struct task_struct
*child
, compat_long_t request
,
942 compat_ulong_t addr
, compat_ulong_t data
)
944 compat_ulong_t __user
*datap
= compat_ptr(data
);
950 case PTRACE_PEEKTEXT
:
951 case PTRACE_PEEKDATA
:
952 ret
= access_process_vm(child
, addr
, &word
, sizeof(word
), 0);
953 if (ret
!= sizeof(word
))
956 ret
= put_user(word
, datap
);
959 case PTRACE_POKETEXT
:
960 case PTRACE_POKEDATA
:
961 ret
= access_process_vm(child
, addr
, &data
, sizeof(data
), 1);
962 ret
= (ret
!= sizeof(data
) ? -EIO
: 0);
965 case PTRACE_GETEVENTMSG
:
966 ret
= put_user((compat_ulong_t
) child
->ptrace_message
, datap
);
969 case PTRACE_GETSIGINFO
:
970 ret
= ptrace_getsiginfo(child
, &siginfo
);
972 ret
= copy_siginfo_to_user32(
973 (struct compat_siginfo __user
*) datap
,
977 case PTRACE_SETSIGINFO
:
978 memset(&siginfo
, 0, sizeof siginfo
);
979 if (copy_siginfo_from_user32(
980 &siginfo
, (struct compat_siginfo __user
*) datap
))
983 ret
= ptrace_setsiginfo(child
, &siginfo
);
985 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
986 case PTRACE_GETREGSET
:
987 case PTRACE_SETREGSET
:
990 struct compat_iovec __user
*uiov
=
991 (struct compat_iovec __user
*) datap
;
995 if (!access_ok(VERIFY_WRITE
, uiov
, sizeof(*uiov
)))
998 if (__get_user(ptr
, &uiov
->iov_base
) ||
999 __get_user(len
, &uiov
->iov_len
))
1002 kiov
.iov_base
= compat_ptr(ptr
);
1005 ret
= ptrace_regset(child
, request
, addr
, &kiov
);
1007 ret
= __put_user(kiov
.iov_len
, &uiov
->iov_len
);
1013 ret
= ptrace_request(child
, request
, addr
, data
);
1019 asmlinkage
long compat_sys_ptrace(compat_long_t request
, compat_long_t pid
,
1020 compat_long_t addr
, compat_long_t data
)
1022 struct task_struct
*child
;
1025 if (request
== PTRACE_TRACEME
) {
1026 ret
= ptrace_traceme();
1030 child
= ptrace_get_task_struct(pid
);
1031 if (IS_ERR(child
)) {
1032 ret
= PTR_ERR(child
);
1036 if (request
== PTRACE_ATTACH
|| request
== PTRACE_SEIZE
) {
1037 ret
= ptrace_attach(child
, request
, data
);
1039 * Some architectures need to do book-keeping after
1043 arch_ptrace_attach(child
);
1044 goto out_put_task_struct
;
1047 ret
= ptrace_check_attach(child
, request
== PTRACE_KILL
||
1048 request
== PTRACE_INTERRUPT
);
1050 ret
= compat_arch_ptrace(child
, request
, addr
, data
);
1052 out_put_task_struct
:
1053 put_task_struct(child
);
1057 #endif /* CONFIG_COMPAT */
1059 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1060 int ptrace_get_breakpoints(struct task_struct
*tsk
)
1062 if (atomic_inc_not_zero(&tsk
->ptrace_bp_refcnt
))
1068 void ptrace_put_breakpoints(struct task_struct
*tsk
)
1070 if (atomic_dec_and_test(&tsk
->ptrace_bp_refcnt
))
1071 flush_ptrace_hw_breakpoint(tsk
);
1073 #endif /* CONFIG_HAVE_HW_BREAKPOINT */