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/sched/mm.h>
14 #include <linux/sched/coredump.h>
15 #include <linux/sched/task.h>
16 #include <linux/errno.h>
18 #include <linux/highmem.h>
19 #include <linux/pagemap.h>
20 #include <linux/ptrace.h>
21 #include <linux/security.h>
22 #include <linux/signal.h>
23 #include <linux/uio.h>
24 #include <linux/audit.h>
25 #include <linux/pid_namespace.h>
26 #include <linux/syscalls.h>
27 #include <linux/uaccess.h>
28 #include <linux/regset.h>
29 #include <linux/hw_breakpoint.h>
30 #include <linux/cn_proc.h>
31 #include <linux/compat.h>
34 * Access another process' address space via ptrace.
35 * Source/target buffer must be kernel space,
36 * Do not walk the page table directly, use get_user_pages
38 int ptrace_access_vm(struct task_struct
*tsk
, unsigned long addr
,
39 void *buf
, int len
, unsigned int gup_flags
)
44 mm
= get_task_mm(tsk
);
49 (current
!= tsk
->parent
) ||
50 ((get_dumpable(mm
) != SUID_DUMP_USER
) &&
51 !ptracer_capable(tsk
, mm
->user_ns
))) {
56 ret
= __access_remote_vm(tsk
, mm
, addr
, buf
, len
, gup_flags
);
64 * ptrace a task: make the debugger its new parent and
65 * move it to the ptrace list.
67 * Must be called with the tasklist lock write-held.
69 void __ptrace_link(struct task_struct
*child
, struct task_struct
*new_parent
)
71 BUG_ON(!list_empty(&child
->ptrace_entry
));
72 list_add(&child
->ptrace_entry
, &new_parent
->ptraced
);
73 child
->parent
= new_parent
;
75 child
->ptracer_cred
= get_cred(__task_cred(new_parent
));
80 * __ptrace_unlink - unlink ptracee and restore its execution state
81 * @child: ptracee to be unlinked
83 * Remove @child from the ptrace list, move it back to the original parent,
84 * and restore the execution state so that it conforms to the group stop
87 * Unlinking can happen via two paths - explicit PTRACE_DETACH or ptracer
88 * exiting. For PTRACE_DETACH, unless the ptracee has been killed between
89 * ptrace_check_attach() and here, it's guaranteed to be in TASK_TRACED.
90 * If the ptracer is exiting, the ptracee can be in any state.
92 * After detach, the ptracee should be in a state which conforms to the
93 * group stop. If the group is stopped or in the process of stopping, the
94 * ptracee should be put into TASK_STOPPED; otherwise, it should be woken
95 * up from TASK_TRACED.
97 * If the ptracee is in TASK_TRACED and needs to be moved to TASK_STOPPED,
98 * it goes through TRACED -> RUNNING -> STOPPED transition which is similar
99 * to but in the opposite direction of what happens while attaching to a
100 * stopped task. However, in this direction, the intermediate RUNNING
101 * state is not hidden even from the current ptracer and if it immediately
102 * re-attaches and performs a WNOHANG wait(2), it may fail.
105 * write_lock_irq(tasklist_lock)
107 void __ptrace_unlink(struct task_struct
*child
)
109 const struct cred
*old_cred
;
110 BUG_ON(!child
->ptrace
);
112 clear_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
114 child
->parent
= child
->real_parent
;
115 list_del_init(&child
->ptrace_entry
);
116 old_cred
= child
->ptracer_cred
;
117 child
->ptracer_cred
= NULL
;
120 spin_lock(&child
->sighand
->siglock
);
123 * Clear all pending traps and TRAPPING. TRAPPING should be
124 * cleared regardless of JOBCTL_STOP_PENDING. Do it explicitly.
126 task_clear_jobctl_pending(child
, JOBCTL_TRAP_MASK
);
127 task_clear_jobctl_trapping(child
);
130 * Reinstate JOBCTL_STOP_PENDING if group stop is in effect and
133 if (!(child
->flags
& PF_EXITING
) &&
134 (child
->signal
->flags
& SIGNAL_STOP_STOPPED
||
135 child
->signal
->group_stop_count
)) {
136 child
->jobctl
|= JOBCTL_STOP_PENDING
;
139 * This is only possible if this thread was cloned by the
140 * traced task running in the stopped group, set the signal
141 * for the future reports.
142 * FIXME: we should change ptrace_init_task() to handle this
145 if (!(child
->jobctl
& JOBCTL_STOP_SIGMASK
))
146 child
->jobctl
|= SIGSTOP
;
150 * If transition to TASK_STOPPED is pending or in TASK_TRACED, kick
151 * @child in the butt. Note that @resume should be used iff @child
152 * is in TASK_TRACED; otherwise, we might unduly disrupt
153 * TASK_KILLABLE sleeps.
155 if (child
->jobctl
& JOBCTL_STOP_PENDING
|| task_is_traced(child
))
156 ptrace_signal_wake_up(child
, true);
158 spin_unlock(&child
->sighand
->siglock
);
161 /* Ensure that nothing can wake it up, even SIGKILL */
162 static bool ptrace_freeze_traced(struct task_struct
*task
)
166 /* Lockless, nobody but us can set this flag */
167 if (task
->jobctl
& JOBCTL_LISTENING
)
170 spin_lock_irq(&task
->sighand
->siglock
);
171 if (task_is_traced(task
) && !__fatal_signal_pending(task
)) {
172 task
->state
= __TASK_TRACED
;
175 spin_unlock_irq(&task
->sighand
->siglock
);
180 static void ptrace_unfreeze_traced(struct task_struct
*task
)
182 if (task
->state
!= __TASK_TRACED
)
185 WARN_ON(!task
->ptrace
|| task
->parent
!= current
);
188 * PTRACE_LISTEN can allow ptrace_trap_notify to wake us up remotely.
189 * Recheck state under the lock to close this race.
191 spin_lock_irq(&task
->sighand
->siglock
);
192 if (task
->state
== __TASK_TRACED
) {
193 if (__fatal_signal_pending(task
))
194 wake_up_state(task
, __TASK_TRACED
);
196 task
->state
= TASK_TRACED
;
198 spin_unlock_irq(&task
->sighand
->siglock
);
202 * ptrace_check_attach - check whether ptracee is ready for ptrace operation
203 * @child: ptracee to check for
204 * @ignore_state: don't check whether @child is currently %TASK_TRACED
206 * Check whether @child is being ptraced by %current and ready for further
207 * ptrace operations. If @ignore_state is %false, @child also should be in
208 * %TASK_TRACED state and on return the child is guaranteed to be traced
209 * and not executing. If @ignore_state is %true, @child can be in any
213 * Grabs and releases tasklist_lock and @child->sighand->siglock.
216 * 0 on success, -ESRCH if %child is not ready.
218 static int ptrace_check_attach(struct task_struct
*child
, bool ignore_state
)
223 * We take the read lock around doing both checks to close a
224 * possible race where someone else was tracing our child and
225 * detached between these two checks. After this locked check,
226 * we are sure that this is our traced child and that can only
227 * be changed by us so it's not changing right after this.
229 read_lock(&tasklist_lock
);
230 if (child
->ptrace
&& child
->parent
== current
) {
231 WARN_ON(child
->state
== __TASK_TRACED
);
233 * child->sighand can't be NULL, release_task()
234 * does ptrace_unlink() before __exit_signal().
236 if (ignore_state
|| ptrace_freeze_traced(child
))
239 read_unlock(&tasklist_lock
);
241 if (!ret
&& !ignore_state
) {
242 if (!wait_task_inactive(child
, __TASK_TRACED
)) {
244 * This can only happen if may_ptrace_stop() fails and
245 * ptrace_stop() changes ->state back to TASK_RUNNING,
246 * so we should not worry about leaking __TASK_TRACED.
248 WARN_ON(child
->state
== __TASK_TRACED
);
256 static int ptrace_has_cap(struct user_namespace
*ns
, unsigned int mode
)
258 if (mode
& PTRACE_MODE_NOAUDIT
)
259 return has_ns_capability_noaudit(current
, ns
, CAP_SYS_PTRACE
);
261 return has_ns_capability(current
, ns
, CAP_SYS_PTRACE
);
264 /* Returns 0 on success, -errno on denial. */
265 static int __ptrace_may_access(struct task_struct
*task
, unsigned int mode
)
267 const struct cred
*cred
= current_cred(), *tcred
;
268 struct mm_struct
*mm
;
272 if (!(mode
& PTRACE_MODE_FSCREDS
) == !(mode
& PTRACE_MODE_REALCREDS
)) {
273 WARN(1, "denying ptrace access check without PTRACE_MODE_*CREDS\n");
277 /* May we inspect the given task?
278 * This check is used both for attaching with ptrace
279 * and for allowing access to sensitive information in /proc.
281 * ptrace_attach denies several cases that /proc allows
282 * because setting up the necessary parent/child relationship
283 * or halting the specified task is impossible.
286 /* Don't let security modules deny introspection */
287 if (same_thread_group(task
, current
))
290 if (mode
& PTRACE_MODE_FSCREDS
) {
291 caller_uid
= cred
->fsuid
;
292 caller_gid
= cred
->fsgid
;
295 * Using the euid would make more sense here, but something
296 * in userland might rely on the old behavior, and this
297 * shouldn't be a security problem since
298 * PTRACE_MODE_REALCREDS implies that the caller explicitly
299 * used a syscall that requests access to another process
300 * (and not a filesystem syscall to procfs).
302 caller_uid
= cred
->uid
;
303 caller_gid
= cred
->gid
;
305 tcred
= __task_cred(task
);
306 if (uid_eq(caller_uid
, tcred
->euid
) &&
307 uid_eq(caller_uid
, tcred
->suid
) &&
308 uid_eq(caller_uid
, tcred
->uid
) &&
309 gid_eq(caller_gid
, tcred
->egid
) &&
310 gid_eq(caller_gid
, tcred
->sgid
) &&
311 gid_eq(caller_gid
, tcred
->gid
))
313 if (ptrace_has_cap(tcred
->user_ns
, mode
))
321 ((get_dumpable(mm
) != SUID_DUMP_USER
) &&
322 !ptrace_has_cap(mm
->user_ns
, mode
)))
325 return security_ptrace_access_check(task
, mode
);
328 bool ptrace_may_access(struct task_struct
*task
, unsigned int mode
)
332 err
= __ptrace_may_access(task
, mode
);
337 static int ptrace_attach(struct task_struct
*task
, long request
,
341 bool seize
= (request
== PTRACE_SEIZE
);
348 if (flags
& ~(unsigned long)PTRACE_O_MASK
)
350 flags
= PT_PTRACED
| PT_SEIZED
| (flags
<< PT_OPT_FLAG_SHIFT
);
358 if (unlikely(task
->flags
& PF_KTHREAD
))
360 if (same_thread_group(task
, current
))
364 * Protect exec's credential calculations against our interference;
365 * SUID, SGID and LSM creds get determined differently
368 retval
= -ERESTARTNOINTR
;
369 if (mutex_lock_interruptible(&task
->signal
->cred_guard_mutex
))
373 retval
= __ptrace_may_access(task
, PTRACE_MODE_ATTACH_REALCREDS
);
378 write_lock_irq(&tasklist_lock
);
380 if (unlikely(task
->exit_state
))
381 goto unlock_tasklist
;
383 goto unlock_tasklist
;
387 task
->ptrace
= flags
;
389 __ptrace_link(task
, current
);
391 /* SEIZE doesn't trap tracee on attach */
393 send_sig_info(SIGSTOP
, SEND_SIG_FORCED
, task
);
395 spin_lock(&task
->sighand
->siglock
);
398 * If the task is already STOPPED, set JOBCTL_TRAP_STOP and
399 * TRAPPING, and kick it so that it transits to TRACED. TRAPPING
400 * will be cleared if the child completes the transition or any
401 * event which clears the group stop states happens. We'll wait
402 * for the transition to complete before returning from this
405 * This hides STOPPED -> RUNNING -> TRACED transition from the
406 * attaching thread but a different thread in the same group can
407 * still observe the transient RUNNING state. IOW, if another
408 * thread's WNOHANG wait(2) on the stopped tracee races against
409 * ATTACH, the wait(2) may fail due to the transient RUNNING.
411 * The following task_is_stopped() test is safe as both transitions
412 * in and out of STOPPED are protected by siglock.
414 if (task_is_stopped(task
) &&
415 task_set_jobctl_pending(task
, JOBCTL_TRAP_STOP
| JOBCTL_TRAPPING
))
416 signal_wake_up_state(task
, __TASK_STOPPED
);
418 spin_unlock(&task
->sighand
->siglock
);
422 write_unlock_irq(&tasklist_lock
);
424 mutex_unlock(&task
->signal
->cred_guard_mutex
);
428 * We do not bother to change retval or clear JOBCTL_TRAPPING
429 * if wait_on_bit() was interrupted by SIGKILL. The tracer will
430 * not return to user-mode, it will exit and clear this bit in
431 * __ptrace_unlink() if it wasn't already cleared by the tracee;
432 * and until then nobody can ptrace this task.
434 wait_on_bit(&task
->jobctl
, JOBCTL_TRAPPING_BIT
, TASK_KILLABLE
);
435 proc_ptrace_connector(task
, PTRACE_ATTACH
);
442 * ptrace_traceme -- helper for PTRACE_TRACEME
444 * Performs checks and sets PT_PTRACED.
445 * Should be used by all ptrace implementations for PTRACE_TRACEME.
447 static int ptrace_traceme(void)
451 write_lock_irq(&tasklist_lock
);
452 /* Are we already being traced? */
453 if (!current
->ptrace
) {
454 ret
= security_ptrace_traceme(current
->parent
);
456 * Check PF_EXITING to ensure ->real_parent has not passed
457 * exit_ptrace(). Otherwise we don't report the error but
458 * pretend ->real_parent untraces us right after return.
460 if (!ret
&& !(current
->real_parent
->flags
& PF_EXITING
)) {
461 current
->ptrace
= PT_PTRACED
;
462 __ptrace_link(current
, current
->real_parent
);
465 write_unlock_irq(&tasklist_lock
);
471 * Called with irqs disabled, returns true if childs should reap themselves.
473 static int ignoring_children(struct sighand_struct
*sigh
)
476 spin_lock(&sigh
->siglock
);
477 ret
= (sigh
->action
[SIGCHLD
-1].sa
.sa_handler
== SIG_IGN
) ||
478 (sigh
->action
[SIGCHLD
-1].sa
.sa_flags
& SA_NOCLDWAIT
);
479 spin_unlock(&sigh
->siglock
);
484 * Called with tasklist_lock held for writing.
485 * Unlink a traced task, and clean it up if it was a traced zombie.
486 * Return true if it needs to be reaped with release_task().
487 * (We can't call release_task() here because we already hold tasklist_lock.)
489 * If it's a zombie, our attachedness prevented normal parent notification
490 * or self-reaping. Do notification now if it would have happened earlier.
491 * If it should reap itself, return true.
493 * If it's our own child, there is no notification to do. But if our normal
494 * children self-reap, then this child was prevented by ptrace and we must
495 * reap it now, in that case we must also wake up sub-threads sleeping in
498 static bool __ptrace_detach(struct task_struct
*tracer
, struct task_struct
*p
)
504 if (p
->exit_state
!= EXIT_ZOMBIE
)
507 dead
= !thread_group_leader(p
);
509 if (!dead
&& thread_group_empty(p
)) {
510 if (!same_thread_group(p
->real_parent
, tracer
))
511 dead
= do_notify_parent(p
, p
->exit_signal
);
512 else if (ignoring_children(tracer
->sighand
)) {
513 __wake_up_parent(p
, tracer
);
517 /* Mark it as in the process of being reaped. */
519 p
->exit_state
= EXIT_DEAD
;
523 static int ptrace_detach(struct task_struct
*child
, unsigned int data
)
525 if (!valid_signal(data
))
528 /* Architecture-specific hardware disable .. */
529 ptrace_disable(child
);
531 write_lock_irq(&tasklist_lock
);
533 * We rely on ptrace_freeze_traced(). It can't be killed and
534 * untraced by another thread, it can't be a zombie.
536 WARN_ON(!child
->ptrace
|| child
->exit_state
);
538 * tasklist_lock avoids the race with wait_task_stopped(), see
539 * the comment in ptrace_resume().
541 child
->exit_code
= data
;
542 __ptrace_detach(current
, child
);
543 write_unlock_irq(&tasklist_lock
);
545 proc_ptrace_connector(child
, PTRACE_DETACH
);
551 * Detach all tasks we were using ptrace on. Called with tasklist held
554 void exit_ptrace(struct task_struct
*tracer
, struct list_head
*dead
)
556 struct task_struct
*p
, *n
;
558 list_for_each_entry_safe(p
, n
, &tracer
->ptraced
, ptrace_entry
) {
559 if (unlikely(p
->ptrace
& PT_EXITKILL
))
560 send_sig_info(SIGKILL
, SEND_SIG_FORCED
, p
);
562 if (__ptrace_detach(tracer
, p
))
563 list_add(&p
->ptrace_entry
, dead
);
567 int ptrace_readdata(struct task_struct
*tsk
, unsigned long src
, char __user
*dst
, int len
)
573 int this_len
, retval
;
575 this_len
= (len
> sizeof(buf
)) ? sizeof(buf
) : len
;
576 retval
= ptrace_access_vm(tsk
, src
, buf
, this_len
, FOLL_FORCE
);
583 if (copy_to_user(dst
, buf
, retval
))
593 int ptrace_writedata(struct task_struct
*tsk
, char __user
*src
, unsigned long dst
, int len
)
599 int this_len
, retval
;
601 this_len
= (len
> sizeof(buf
)) ? sizeof(buf
) : len
;
602 if (copy_from_user(buf
, src
, this_len
))
604 retval
= ptrace_access_vm(tsk
, dst
, buf
, this_len
,
605 FOLL_FORCE
| FOLL_WRITE
);
619 static int ptrace_setoptions(struct task_struct
*child
, unsigned long data
)
623 if (data
& ~(unsigned long)PTRACE_O_MASK
)
626 if (unlikely(data
& PTRACE_O_SUSPEND_SECCOMP
)) {
627 if (!IS_ENABLED(CONFIG_CHECKPOINT_RESTORE
) ||
628 !IS_ENABLED(CONFIG_SECCOMP
))
631 if (!capable(CAP_SYS_ADMIN
))
634 if (seccomp_mode(¤t
->seccomp
) != SECCOMP_MODE_DISABLED
||
635 current
->ptrace
& PT_SUSPEND_SECCOMP
)
639 /* Avoid intermediate state when all opts are cleared */
640 flags
= child
->ptrace
;
641 flags
&= ~(PTRACE_O_MASK
<< PT_OPT_FLAG_SHIFT
);
642 flags
|= (data
<< PT_OPT_FLAG_SHIFT
);
643 child
->ptrace
= flags
;
648 static int ptrace_getsiginfo(struct task_struct
*child
, siginfo_t
*info
)
653 if (lock_task_sighand(child
, &flags
)) {
655 if (likely(child
->last_siginfo
!= NULL
)) {
656 *info
= *child
->last_siginfo
;
659 unlock_task_sighand(child
, &flags
);
664 static int ptrace_setsiginfo(struct task_struct
*child
, const siginfo_t
*info
)
669 if (lock_task_sighand(child
, &flags
)) {
671 if (likely(child
->last_siginfo
!= NULL
)) {
672 *child
->last_siginfo
= *info
;
675 unlock_task_sighand(child
, &flags
);
680 static int ptrace_peek_siginfo(struct task_struct
*child
,
684 struct ptrace_peeksiginfo_args arg
;
685 struct sigpending
*pending
;
689 ret
= copy_from_user(&arg
, (void __user
*) addr
,
690 sizeof(struct ptrace_peeksiginfo_args
));
694 if (arg
.flags
& ~PTRACE_PEEKSIGINFO_SHARED
)
695 return -EINVAL
; /* unknown flags */
700 if (arg
.flags
& PTRACE_PEEKSIGINFO_SHARED
)
701 pending
= &child
->signal
->shared_pending
;
703 pending
= &child
->pending
;
705 for (i
= 0; i
< arg
.nr
; ) {
707 s32 off
= arg
.off
+ i
;
709 spin_lock_irq(&child
->sighand
->siglock
);
710 list_for_each_entry(q
, &pending
->list
, list
) {
712 copy_siginfo(&info
, &q
->info
);
716 spin_unlock_irq(&child
->sighand
->siglock
);
718 if (off
>= 0) /* beyond the end of the list */
722 if (unlikely(in_compat_syscall())) {
723 compat_siginfo_t __user
*uinfo
= compat_ptr(data
);
725 if (copy_siginfo_to_user32(uinfo
, &info
) ||
726 __put_user(info
.si_code
, &uinfo
->si_code
)) {
734 siginfo_t __user
*uinfo
= (siginfo_t __user
*) data
;
736 if (copy_siginfo_to_user(uinfo
, &info
) ||
737 __put_user(info
.si_code
, &uinfo
->si_code
)) {
743 data
+= sizeof(siginfo_t
);
746 if (signal_pending(current
))
758 #ifdef PTRACE_SINGLESTEP
759 #define is_singlestep(request) ((request) == PTRACE_SINGLESTEP)
761 #define is_singlestep(request) 0
764 #ifdef PTRACE_SINGLEBLOCK
765 #define is_singleblock(request) ((request) == PTRACE_SINGLEBLOCK)
767 #define is_singleblock(request) 0
771 #define is_sysemu_singlestep(request) ((request) == PTRACE_SYSEMU_SINGLESTEP)
773 #define is_sysemu_singlestep(request) 0
776 static int ptrace_resume(struct task_struct
*child
, long request
,
781 if (!valid_signal(data
))
784 if (request
== PTRACE_SYSCALL
)
785 set_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
787 clear_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
789 #ifdef TIF_SYSCALL_EMU
790 if (request
== PTRACE_SYSEMU
|| request
== PTRACE_SYSEMU_SINGLESTEP
)
791 set_tsk_thread_flag(child
, TIF_SYSCALL_EMU
);
793 clear_tsk_thread_flag(child
, TIF_SYSCALL_EMU
);
796 if (is_singleblock(request
)) {
797 if (unlikely(!arch_has_block_step()))
799 user_enable_block_step(child
);
800 } else if (is_singlestep(request
) || is_sysemu_singlestep(request
)) {
801 if (unlikely(!arch_has_single_step()))
803 user_enable_single_step(child
);
805 user_disable_single_step(child
);
809 * Change ->exit_code and ->state under siglock to avoid the race
810 * with wait_task_stopped() in between; a non-zero ->exit_code will
811 * wrongly look like another report from tracee.
813 * Note that we need siglock even if ->exit_code == data and/or this
814 * status was not reported yet, the new status must not be cleared by
815 * wait_task_stopped() after resume.
817 * If data == 0 we do not care if wait_task_stopped() reports the old
818 * status and clears the code too; this can't race with the tracee, it
819 * takes siglock after resume.
821 need_siglock
= data
&& !thread_group_empty(current
);
823 spin_lock_irq(&child
->sighand
->siglock
);
824 child
->exit_code
= data
;
825 wake_up_state(child
, __TASK_TRACED
);
827 spin_unlock_irq(&child
->sighand
->siglock
);
832 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
834 static const struct user_regset
*
835 find_regset(const struct user_regset_view
*view
, unsigned int type
)
837 const struct user_regset
*regset
;
840 for (n
= 0; n
< view
->n
; ++n
) {
841 regset
= view
->regsets
+ n
;
842 if (regset
->core_note_type
== type
)
849 static int ptrace_regset(struct task_struct
*task
, int req
, unsigned int type
,
852 const struct user_regset_view
*view
= task_user_regset_view(task
);
853 const struct user_regset
*regset
= find_regset(view
, type
);
856 if (!regset
|| (kiov
->iov_len
% regset
->size
) != 0)
859 regset_no
= regset
- view
->regsets
;
860 kiov
->iov_len
= min(kiov
->iov_len
,
861 (__kernel_size_t
) (regset
->n
* regset
->size
));
863 if (req
== PTRACE_GETREGSET
)
864 return copy_regset_to_user(task
, view
, regset_no
, 0,
865 kiov
->iov_len
, kiov
->iov_base
);
867 return copy_regset_from_user(task
, view
, regset_no
, 0,
868 kiov
->iov_len
, kiov
->iov_base
);
872 * This is declared in linux/regset.h and defined in machine-dependent
873 * code. We put the export here, near the primary machine-neutral use,
874 * to ensure no machine forgets it.
876 EXPORT_SYMBOL_GPL(task_user_regset_view
);
879 int ptrace_request(struct task_struct
*child
, long request
,
880 unsigned long addr
, unsigned long data
)
882 bool seized
= child
->ptrace
& PT_SEIZED
;
884 siginfo_t siginfo
, *si
;
885 void __user
*datavp
= (void __user
*) data
;
886 unsigned long __user
*datalp
= datavp
;
890 case PTRACE_PEEKTEXT
:
891 case PTRACE_PEEKDATA
:
892 return generic_ptrace_peekdata(child
, addr
, data
);
893 case PTRACE_POKETEXT
:
894 case PTRACE_POKEDATA
:
895 return generic_ptrace_pokedata(child
, addr
, data
);
897 #ifdef PTRACE_OLDSETOPTIONS
898 case PTRACE_OLDSETOPTIONS
:
900 case PTRACE_SETOPTIONS
:
901 ret
= ptrace_setoptions(child
, data
);
903 case PTRACE_GETEVENTMSG
:
904 ret
= put_user(child
->ptrace_message
, datalp
);
907 case PTRACE_PEEKSIGINFO
:
908 ret
= ptrace_peek_siginfo(child
, addr
, data
);
911 case PTRACE_GETSIGINFO
:
912 ret
= ptrace_getsiginfo(child
, &siginfo
);
914 ret
= copy_siginfo_to_user(datavp
, &siginfo
);
917 case PTRACE_SETSIGINFO
:
918 if (copy_from_user(&siginfo
, datavp
, sizeof siginfo
))
921 ret
= ptrace_setsiginfo(child
, &siginfo
);
924 case PTRACE_GETSIGMASK
:
925 if (addr
!= sizeof(sigset_t
)) {
930 if (copy_to_user(datavp
, &child
->blocked
, sizeof(sigset_t
)))
937 case PTRACE_SETSIGMASK
: {
940 if (addr
!= sizeof(sigset_t
)) {
945 if (copy_from_user(&new_set
, datavp
, sizeof(sigset_t
))) {
950 sigdelsetmask(&new_set
, sigmask(SIGKILL
)|sigmask(SIGSTOP
));
953 * Every thread does recalc_sigpending() after resume, so
954 * retarget_shared_pending() and recalc_sigpending() are not
957 spin_lock_irq(&child
->sighand
->siglock
);
958 child
->blocked
= new_set
;
959 spin_unlock_irq(&child
->sighand
->siglock
);
965 case PTRACE_INTERRUPT
:
967 * Stop tracee without any side-effect on signal or job
968 * control. At least one trap is guaranteed to happen
969 * after this request. If @child is already trapped, the
970 * current trap is not disturbed and another trap will
971 * happen after the current trap is ended with PTRACE_CONT.
973 * The actual trap might not be PTRACE_EVENT_STOP trap but
974 * the pending condition is cleared regardless.
976 if (unlikely(!seized
|| !lock_task_sighand(child
, &flags
)))
980 * INTERRUPT doesn't disturb existing trap sans one
981 * exception. If ptracer issued LISTEN for the current
982 * STOP, this INTERRUPT should clear LISTEN and re-trap
985 if (likely(task_set_jobctl_pending(child
, JOBCTL_TRAP_STOP
)))
986 ptrace_signal_wake_up(child
, child
->jobctl
& JOBCTL_LISTENING
);
988 unlock_task_sighand(child
, &flags
);
994 * Listen for events. Tracee must be in STOP. It's not
995 * resumed per-se but is not considered to be in TRACED by
996 * wait(2) or ptrace(2). If an async event (e.g. group
997 * stop state change) happens, tracee will enter STOP trap
998 * again. Alternatively, ptracer can issue INTERRUPT to
999 * finish listening and re-trap tracee into STOP.
1001 if (unlikely(!seized
|| !lock_task_sighand(child
, &flags
)))
1004 si
= child
->last_siginfo
;
1005 if (likely(si
&& (si
->si_code
>> 8) == PTRACE_EVENT_STOP
)) {
1006 child
->jobctl
|= JOBCTL_LISTENING
;
1008 * If NOTIFY is set, it means event happened between
1009 * start of this trap and now. Trigger re-trap.
1011 if (child
->jobctl
& JOBCTL_TRAP_NOTIFY
)
1012 ptrace_signal_wake_up(child
, true);
1015 unlock_task_sighand(child
, &flags
);
1018 case PTRACE_DETACH
: /* detach a process that was attached. */
1019 ret
= ptrace_detach(child
, data
);
1022 #ifdef CONFIG_BINFMT_ELF_FDPIC
1023 case PTRACE_GETFDPIC
: {
1024 struct mm_struct
*mm
= get_task_mm(child
);
1025 unsigned long tmp
= 0;
1032 case PTRACE_GETFDPIC_EXEC
:
1033 tmp
= mm
->context
.exec_fdpic_loadmap
;
1035 case PTRACE_GETFDPIC_INTERP
:
1036 tmp
= mm
->context
.interp_fdpic_loadmap
;
1043 ret
= put_user(tmp
, datalp
);
1048 #ifdef PTRACE_SINGLESTEP
1049 case PTRACE_SINGLESTEP
:
1051 #ifdef PTRACE_SINGLEBLOCK
1052 case PTRACE_SINGLEBLOCK
:
1054 #ifdef PTRACE_SYSEMU
1056 case PTRACE_SYSEMU_SINGLESTEP
:
1058 case PTRACE_SYSCALL
:
1060 return ptrace_resume(child
, request
, data
);
1063 if (child
->exit_state
) /* already dead */
1065 return ptrace_resume(child
, request
, SIGKILL
);
1067 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
1068 case PTRACE_GETREGSET
:
1069 case PTRACE_SETREGSET
: {
1071 struct iovec __user
*uiov
= datavp
;
1073 if (!access_ok(VERIFY_WRITE
, uiov
, sizeof(*uiov
)))
1076 if (__get_user(kiov
.iov_base
, &uiov
->iov_base
) ||
1077 __get_user(kiov
.iov_len
, &uiov
->iov_len
))
1080 ret
= ptrace_regset(child
, request
, addr
, &kiov
);
1082 ret
= __put_user(kiov
.iov_len
, &uiov
->iov_len
);
1087 case PTRACE_SECCOMP_GET_FILTER
:
1088 ret
= seccomp_get_filter(child
, addr
, datavp
);
1098 static struct task_struct
*ptrace_get_task_struct(pid_t pid
)
1100 struct task_struct
*child
;
1103 child
= find_task_by_vpid(pid
);
1105 get_task_struct(child
);
1109 return ERR_PTR(-ESRCH
);
1113 #ifndef arch_ptrace_attach
1114 #define arch_ptrace_attach(child) do { } while (0)
1117 SYSCALL_DEFINE4(ptrace
, long, request
, long, pid
, unsigned long, addr
,
1118 unsigned long, data
)
1120 struct task_struct
*child
;
1123 if (request
== PTRACE_TRACEME
) {
1124 ret
= ptrace_traceme();
1126 arch_ptrace_attach(current
);
1130 child
= ptrace_get_task_struct(pid
);
1131 if (IS_ERR(child
)) {
1132 ret
= PTR_ERR(child
);
1136 if (request
== PTRACE_ATTACH
|| request
== PTRACE_SEIZE
) {
1137 ret
= ptrace_attach(child
, request
, addr
, data
);
1139 * Some architectures need to do book-keeping after
1143 arch_ptrace_attach(child
);
1144 goto out_put_task_struct
;
1147 ret
= ptrace_check_attach(child
, request
== PTRACE_KILL
||
1148 request
== PTRACE_INTERRUPT
);
1150 goto out_put_task_struct
;
1152 ret
= arch_ptrace(child
, request
, addr
, data
);
1153 if (ret
|| request
!= PTRACE_DETACH
)
1154 ptrace_unfreeze_traced(child
);
1156 out_put_task_struct
:
1157 put_task_struct(child
);
1162 int generic_ptrace_peekdata(struct task_struct
*tsk
, unsigned long addr
,
1168 copied
= ptrace_access_vm(tsk
, addr
, &tmp
, sizeof(tmp
), FOLL_FORCE
);
1169 if (copied
!= sizeof(tmp
))
1171 return put_user(tmp
, (unsigned long __user
*)data
);
1174 int generic_ptrace_pokedata(struct task_struct
*tsk
, unsigned long addr
,
1179 copied
= ptrace_access_vm(tsk
, addr
, &data
, sizeof(data
),
1180 FOLL_FORCE
| FOLL_WRITE
);
1181 return (copied
== sizeof(data
)) ? 0 : -EIO
;
1184 #if defined CONFIG_COMPAT
1186 int compat_ptrace_request(struct task_struct
*child
, compat_long_t request
,
1187 compat_ulong_t addr
, compat_ulong_t data
)
1189 compat_ulong_t __user
*datap
= compat_ptr(data
);
1190 compat_ulong_t word
;
1195 case PTRACE_PEEKTEXT
:
1196 case PTRACE_PEEKDATA
:
1197 ret
= ptrace_access_vm(child
, addr
, &word
, sizeof(word
),
1199 if (ret
!= sizeof(word
))
1202 ret
= put_user(word
, datap
);
1205 case PTRACE_POKETEXT
:
1206 case PTRACE_POKEDATA
:
1207 ret
= ptrace_access_vm(child
, addr
, &data
, sizeof(data
),
1208 FOLL_FORCE
| FOLL_WRITE
);
1209 ret
= (ret
!= sizeof(data
) ? -EIO
: 0);
1212 case PTRACE_GETEVENTMSG
:
1213 ret
= put_user((compat_ulong_t
) child
->ptrace_message
, datap
);
1216 case PTRACE_GETSIGINFO
:
1217 ret
= ptrace_getsiginfo(child
, &siginfo
);
1219 ret
= copy_siginfo_to_user32(
1220 (struct compat_siginfo __user
*) datap
,
1224 case PTRACE_SETSIGINFO
:
1225 memset(&siginfo
, 0, sizeof siginfo
);
1226 if (copy_siginfo_from_user32(
1227 &siginfo
, (struct compat_siginfo __user
*) datap
))
1230 ret
= ptrace_setsiginfo(child
, &siginfo
);
1232 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
1233 case PTRACE_GETREGSET
:
1234 case PTRACE_SETREGSET
:
1237 struct compat_iovec __user
*uiov
=
1238 (struct compat_iovec __user
*) datap
;
1242 if (!access_ok(VERIFY_WRITE
, uiov
, sizeof(*uiov
)))
1245 if (__get_user(ptr
, &uiov
->iov_base
) ||
1246 __get_user(len
, &uiov
->iov_len
))
1249 kiov
.iov_base
= compat_ptr(ptr
);
1252 ret
= ptrace_regset(child
, request
, addr
, &kiov
);
1254 ret
= __put_user(kiov
.iov_len
, &uiov
->iov_len
);
1260 ret
= ptrace_request(child
, request
, addr
, data
);
1266 COMPAT_SYSCALL_DEFINE4(ptrace
, compat_long_t
, request
, compat_long_t
, pid
,
1267 compat_long_t
, addr
, compat_long_t
, data
)
1269 struct task_struct
*child
;
1272 if (request
== PTRACE_TRACEME
) {
1273 ret
= ptrace_traceme();
1277 child
= ptrace_get_task_struct(pid
);
1278 if (IS_ERR(child
)) {
1279 ret
= PTR_ERR(child
);
1283 if (request
== PTRACE_ATTACH
|| request
== PTRACE_SEIZE
) {
1284 ret
= ptrace_attach(child
, request
, addr
, data
);
1286 * Some architectures need to do book-keeping after
1290 arch_ptrace_attach(child
);
1291 goto out_put_task_struct
;
1294 ret
= ptrace_check_attach(child
, request
== PTRACE_KILL
||
1295 request
== PTRACE_INTERRUPT
);
1297 ret
= compat_arch_ptrace(child
, request
, addr
, data
);
1298 if (ret
|| request
!= PTRACE_DETACH
)
1299 ptrace_unfreeze_traced(child
);
1302 out_put_task_struct
:
1303 put_task_struct(child
);
1307 #endif /* CONFIG_COMPAT */