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>
32 #include <linux/sched/signal.h>
35 * Access another process' address space via ptrace.
36 * Source/target buffer must be kernel space,
37 * Do not walk the page table directly, use get_user_pages
39 int ptrace_access_vm(struct task_struct
*tsk
, unsigned long addr
,
40 void *buf
, int len
, unsigned int gup_flags
)
45 mm
= get_task_mm(tsk
);
50 (current
!= tsk
->parent
) ||
51 ((get_dumpable(mm
) != SUID_DUMP_USER
) &&
52 !ptracer_capable(tsk
, mm
->user_ns
))) {
57 ret
= __access_remote_vm(tsk
, mm
, addr
, buf
, len
, gup_flags
);
64 void __ptrace_link(struct task_struct
*child
, struct task_struct
*new_parent
,
65 const struct cred
*ptracer_cred
)
67 BUG_ON(!list_empty(&child
->ptrace_entry
));
68 list_add(&child
->ptrace_entry
, &new_parent
->ptraced
);
69 child
->parent
= new_parent
;
70 child
->ptracer_cred
= get_cred(ptracer_cred
);
74 * ptrace a task: make the debugger its new parent and
75 * move it to the ptrace list.
77 * Must be called with the tasklist lock write-held.
79 static void ptrace_link(struct task_struct
*child
, struct task_struct
*new_parent
)
81 __ptrace_link(child
, new_parent
, current_cred());
85 * __ptrace_unlink - unlink ptracee and restore its execution state
86 * @child: ptracee to be unlinked
88 * Remove @child from the ptrace list, move it back to the original parent,
89 * and restore the execution state so that it conforms to the group stop
92 * Unlinking can happen via two paths - explicit PTRACE_DETACH or ptracer
93 * exiting. For PTRACE_DETACH, unless the ptracee has been killed between
94 * ptrace_check_attach() and here, it's guaranteed to be in TASK_TRACED.
95 * If the ptracer is exiting, the ptracee can be in any state.
97 * After detach, the ptracee should be in a state which conforms to the
98 * group stop. If the group is stopped or in the process of stopping, the
99 * ptracee should be put into TASK_STOPPED; otherwise, it should be woken
100 * up from TASK_TRACED.
102 * If the ptracee is in TASK_TRACED and needs to be moved to TASK_STOPPED,
103 * it goes through TRACED -> RUNNING -> STOPPED transition which is similar
104 * to but in the opposite direction of what happens while attaching to a
105 * stopped task. However, in this direction, the intermediate RUNNING
106 * state is not hidden even from the current ptracer and if it immediately
107 * re-attaches and performs a WNOHANG wait(2), it may fail.
110 * write_lock_irq(tasklist_lock)
112 void __ptrace_unlink(struct task_struct
*child
)
114 const struct cred
*old_cred
;
115 BUG_ON(!child
->ptrace
);
117 clear_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
119 child
->parent
= child
->real_parent
;
120 list_del_init(&child
->ptrace_entry
);
121 old_cred
= child
->ptracer_cred
;
122 child
->ptracer_cred
= NULL
;
125 spin_lock(&child
->sighand
->siglock
);
128 * Clear all pending traps and TRAPPING. TRAPPING should be
129 * cleared regardless of JOBCTL_STOP_PENDING. Do it explicitly.
131 task_clear_jobctl_pending(child
, JOBCTL_TRAP_MASK
);
132 task_clear_jobctl_trapping(child
);
135 * Reinstate JOBCTL_STOP_PENDING if group stop is in effect and
138 if (!(child
->flags
& PF_EXITING
) &&
139 (child
->signal
->flags
& SIGNAL_STOP_STOPPED
||
140 child
->signal
->group_stop_count
)) {
141 child
->jobctl
|= JOBCTL_STOP_PENDING
;
144 * This is only possible if this thread was cloned by the
145 * traced task running in the stopped group, set the signal
146 * for the future reports.
147 * FIXME: we should change ptrace_init_task() to handle this
150 if (!(child
->jobctl
& JOBCTL_STOP_SIGMASK
))
151 child
->jobctl
|= SIGSTOP
;
155 * If transition to TASK_STOPPED is pending or in TASK_TRACED, kick
156 * @child in the butt. Note that @resume should be used iff @child
157 * is in TASK_TRACED; otherwise, we might unduly disrupt
158 * TASK_KILLABLE sleeps.
160 if (child
->jobctl
& JOBCTL_STOP_PENDING
|| task_is_traced(child
))
161 ptrace_signal_wake_up(child
, true);
163 spin_unlock(&child
->sighand
->siglock
);
166 /* Ensure that nothing can wake it up, even SIGKILL */
167 static bool ptrace_freeze_traced(struct task_struct
*task
)
171 /* Lockless, nobody but us can set this flag */
172 if (task
->jobctl
& JOBCTL_LISTENING
)
175 spin_lock_irq(&task
->sighand
->siglock
);
176 if (task_is_traced(task
) && !__fatal_signal_pending(task
)) {
177 task
->state
= __TASK_TRACED
;
180 spin_unlock_irq(&task
->sighand
->siglock
);
185 static void ptrace_unfreeze_traced(struct task_struct
*task
)
187 if (task
->state
!= __TASK_TRACED
)
190 WARN_ON(!task
->ptrace
|| task
->parent
!= current
);
193 * PTRACE_LISTEN can allow ptrace_trap_notify to wake us up remotely.
194 * Recheck state under the lock to close this race.
196 spin_lock_irq(&task
->sighand
->siglock
);
197 if (task
->state
== __TASK_TRACED
) {
198 if (__fatal_signal_pending(task
))
199 wake_up_state(task
, __TASK_TRACED
);
201 task
->state
= TASK_TRACED
;
203 spin_unlock_irq(&task
->sighand
->siglock
);
207 * ptrace_check_attach - check whether ptracee is ready for ptrace operation
208 * @child: ptracee to check for
209 * @ignore_state: don't check whether @child is currently %TASK_TRACED
211 * Check whether @child is being ptraced by %current and ready for further
212 * ptrace operations. If @ignore_state is %false, @child also should be in
213 * %TASK_TRACED state and on return the child is guaranteed to be traced
214 * and not executing. If @ignore_state is %true, @child can be in any
218 * Grabs and releases tasklist_lock and @child->sighand->siglock.
221 * 0 on success, -ESRCH if %child is not ready.
223 static int ptrace_check_attach(struct task_struct
*child
, bool ignore_state
)
228 * We take the read lock around doing both checks to close a
229 * possible race where someone else was tracing our child and
230 * detached between these two checks. After this locked check,
231 * we are sure that this is our traced child and that can only
232 * be changed by us so it's not changing right after this.
234 read_lock(&tasklist_lock
);
235 if (child
->ptrace
&& child
->parent
== current
) {
236 WARN_ON(child
->state
== __TASK_TRACED
);
238 * child->sighand can't be NULL, release_task()
239 * does ptrace_unlink() before __exit_signal().
241 if (ignore_state
|| ptrace_freeze_traced(child
))
244 read_unlock(&tasklist_lock
);
246 if (!ret
&& !ignore_state
) {
247 if (!wait_task_inactive(child
, __TASK_TRACED
)) {
249 * This can only happen if may_ptrace_stop() fails and
250 * ptrace_stop() changes ->state back to TASK_RUNNING,
251 * so we should not worry about leaking __TASK_TRACED.
253 WARN_ON(child
->state
== __TASK_TRACED
);
261 static int ptrace_has_cap(struct user_namespace
*ns
, unsigned int mode
)
263 if (mode
& PTRACE_MODE_NOAUDIT
)
264 return has_ns_capability_noaudit(current
, ns
, CAP_SYS_PTRACE
);
266 return has_ns_capability(current
, ns
, CAP_SYS_PTRACE
);
269 /* Returns 0 on success, -errno on denial. */
270 static int __ptrace_may_access(struct task_struct
*task
, unsigned int mode
)
272 const struct cred
*cred
= current_cred(), *tcred
;
273 struct mm_struct
*mm
;
277 if (!(mode
& PTRACE_MODE_FSCREDS
) == !(mode
& PTRACE_MODE_REALCREDS
)) {
278 WARN(1, "denying ptrace access check without PTRACE_MODE_*CREDS\n");
282 /* May we inspect the given task?
283 * This check is used both for attaching with ptrace
284 * and for allowing access to sensitive information in /proc.
286 * ptrace_attach denies several cases that /proc allows
287 * because setting up the necessary parent/child relationship
288 * or halting the specified task is impossible.
291 /* Don't let security modules deny introspection */
292 if (same_thread_group(task
, current
))
295 if (mode
& PTRACE_MODE_FSCREDS
) {
296 caller_uid
= cred
->fsuid
;
297 caller_gid
= cred
->fsgid
;
300 * Using the euid would make more sense here, but something
301 * in userland might rely on the old behavior, and this
302 * shouldn't be a security problem since
303 * PTRACE_MODE_REALCREDS implies that the caller explicitly
304 * used a syscall that requests access to another process
305 * (and not a filesystem syscall to procfs).
307 caller_uid
= cred
->uid
;
308 caller_gid
= cred
->gid
;
310 tcred
= __task_cred(task
);
311 if (uid_eq(caller_uid
, tcred
->euid
) &&
312 uid_eq(caller_uid
, tcred
->suid
) &&
313 uid_eq(caller_uid
, tcred
->uid
) &&
314 gid_eq(caller_gid
, tcred
->egid
) &&
315 gid_eq(caller_gid
, tcred
->sgid
) &&
316 gid_eq(caller_gid
, tcred
->gid
))
318 if (ptrace_has_cap(tcred
->user_ns
, mode
))
326 ((get_dumpable(mm
) != SUID_DUMP_USER
) &&
327 !ptrace_has_cap(mm
->user_ns
, mode
)))
330 return security_ptrace_access_check(task
, mode
);
333 bool ptrace_may_access(struct task_struct
*task
, unsigned int mode
)
337 err
= __ptrace_may_access(task
, mode
);
342 static int ptrace_attach(struct task_struct
*task
, long request
,
346 bool seize
= (request
== PTRACE_SEIZE
);
353 if (flags
& ~(unsigned long)PTRACE_O_MASK
)
355 flags
= PT_PTRACED
| PT_SEIZED
| (flags
<< PT_OPT_FLAG_SHIFT
);
363 if (unlikely(task
->flags
& PF_KTHREAD
))
365 if (same_thread_group(task
, current
))
369 * Protect exec's credential calculations against our interference;
370 * SUID, SGID and LSM creds get determined differently
373 retval
= -ERESTARTNOINTR
;
374 if (mutex_lock_interruptible(&task
->signal
->cred_guard_mutex
))
378 retval
= __ptrace_may_access(task
, PTRACE_MODE_ATTACH_REALCREDS
);
383 write_lock_irq(&tasklist_lock
);
385 if (unlikely(task
->exit_state
))
386 goto unlock_tasklist
;
388 goto unlock_tasklist
;
392 task
->ptrace
= flags
;
394 ptrace_link(task
, current
);
396 /* SEIZE doesn't trap tracee on attach */
398 send_sig_info(SIGSTOP
, SEND_SIG_PRIV
, task
);
400 spin_lock(&task
->sighand
->siglock
);
403 * If the task is already STOPPED, set JOBCTL_TRAP_STOP and
404 * TRAPPING, and kick it so that it transits to TRACED. TRAPPING
405 * will be cleared if the child completes the transition or any
406 * event which clears the group stop states happens. We'll wait
407 * for the transition to complete before returning from this
410 * This hides STOPPED -> RUNNING -> TRACED transition from the
411 * attaching thread but a different thread in the same group can
412 * still observe the transient RUNNING state. IOW, if another
413 * thread's WNOHANG wait(2) on the stopped tracee races against
414 * ATTACH, the wait(2) may fail due to the transient RUNNING.
416 * The following task_is_stopped() test is safe as both transitions
417 * in and out of STOPPED are protected by siglock.
419 if (task_is_stopped(task
) &&
420 task_set_jobctl_pending(task
, JOBCTL_TRAP_STOP
| JOBCTL_TRAPPING
))
421 signal_wake_up_state(task
, __TASK_STOPPED
);
423 spin_unlock(&task
->sighand
->siglock
);
427 write_unlock_irq(&tasklist_lock
);
429 mutex_unlock(&task
->signal
->cred_guard_mutex
);
433 * We do not bother to change retval or clear JOBCTL_TRAPPING
434 * if wait_on_bit() was interrupted by SIGKILL. The tracer will
435 * not return to user-mode, it will exit and clear this bit in
436 * __ptrace_unlink() if it wasn't already cleared by the tracee;
437 * and until then nobody can ptrace this task.
439 wait_on_bit(&task
->jobctl
, JOBCTL_TRAPPING_BIT
, TASK_KILLABLE
);
440 proc_ptrace_connector(task
, PTRACE_ATTACH
);
447 * ptrace_traceme -- helper for PTRACE_TRACEME
449 * Performs checks and sets PT_PTRACED.
450 * Should be used by all ptrace implementations for PTRACE_TRACEME.
452 static int ptrace_traceme(void)
456 write_lock_irq(&tasklist_lock
);
457 /* Are we already being traced? */
458 if (!current
->ptrace
) {
459 ret
= security_ptrace_traceme(current
->parent
);
461 * Check PF_EXITING to ensure ->real_parent has not passed
462 * exit_ptrace(). Otherwise we don't report the error but
463 * pretend ->real_parent untraces us right after return.
465 if (!ret
&& !(current
->real_parent
->flags
& PF_EXITING
)) {
466 current
->ptrace
= PT_PTRACED
;
467 ptrace_link(current
, current
->real_parent
);
470 write_unlock_irq(&tasklist_lock
);
476 * Called with irqs disabled, returns true if childs should reap themselves.
478 static int ignoring_children(struct sighand_struct
*sigh
)
481 spin_lock(&sigh
->siglock
);
482 ret
= (sigh
->action
[SIGCHLD
-1].sa
.sa_handler
== SIG_IGN
) ||
483 (sigh
->action
[SIGCHLD
-1].sa
.sa_flags
& SA_NOCLDWAIT
);
484 spin_unlock(&sigh
->siglock
);
489 * Called with tasklist_lock held for writing.
490 * Unlink a traced task, and clean it up if it was a traced zombie.
491 * Return true if it needs to be reaped with release_task().
492 * (We can't call release_task() here because we already hold tasklist_lock.)
494 * If it's a zombie, our attachedness prevented normal parent notification
495 * or self-reaping. Do notification now if it would have happened earlier.
496 * If it should reap itself, return true.
498 * If it's our own child, there is no notification to do. But if our normal
499 * children self-reap, then this child was prevented by ptrace and we must
500 * reap it now, in that case we must also wake up sub-threads sleeping in
503 static bool __ptrace_detach(struct task_struct
*tracer
, struct task_struct
*p
)
509 if (p
->exit_state
!= EXIT_ZOMBIE
)
512 dead
= !thread_group_leader(p
);
514 if (!dead
&& thread_group_empty(p
)) {
515 if (!same_thread_group(p
->real_parent
, tracer
))
516 dead
= do_notify_parent(p
, p
->exit_signal
);
517 else if (ignoring_children(tracer
->sighand
)) {
518 __wake_up_parent(p
, tracer
);
522 /* Mark it as in the process of being reaped. */
524 p
->exit_state
= EXIT_DEAD
;
528 static int ptrace_detach(struct task_struct
*child
, unsigned int data
)
530 if (!valid_signal(data
))
533 /* Architecture-specific hardware disable .. */
534 ptrace_disable(child
);
536 write_lock_irq(&tasklist_lock
);
538 * We rely on ptrace_freeze_traced(). It can't be killed and
539 * untraced by another thread, it can't be a zombie.
541 WARN_ON(!child
->ptrace
|| child
->exit_state
);
543 * tasklist_lock avoids the race with wait_task_stopped(), see
544 * the comment in ptrace_resume().
546 child
->exit_code
= data
;
547 __ptrace_detach(current
, child
);
548 write_unlock_irq(&tasklist_lock
);
550 proc_ptrace_connector(child
, PTRACE_DETACH
);
556 * Detach all tasks we were using ptrace on. Called with tasklist held
559 void exit_ptrace(struct task_struct
*tracer
, struct list_head
*dead
)
561 struct task_struct
*p
, *n
;
563 list_for_each_entry_safe(p
, n
, &tracer
->ptraced
, ptrace_entry
) {
564 if (unlikely(p
->ptrace
& PT_EXITKILL
))
565 send_sig_info(SIGKILL
, SEND_SIG_PRIV
, p
);
567 if (__ptrace_detach(tracer
, p
))
568 list_add(&p
->ptrace_entry
, dead
);
572 int ptrace_readdata(struct task_struct
*tsk
, unsigned long src
, char __user
*dst
, int len
)
578 int this_len
, retval
;
580 this_len
= (len
> sizeof(buf
)) ? sizeof(buf
) : len
;
581 retval
= ptrace_access_vm(tsk
, src
, buf
, this_len
, FOLL_FORCE
);
588 if (copy_to_user(dst
, buf
, retval
))
598 int ptrace_writedata(struct task_struct
*tsk
, char __user
*src
, unsigned long dst
, int len
)
604 int this_len
, retval
;
606 this_len
= (len
> sizeof(buf
)) ? sizeof(buf
) : len
;
607 if (copy_from_user(buf
, src
, this_len
))
609 retval
= ptrace_access_vm(tsk
, dst
, buf
, this_len
,
610 FOLL_FORCE
| FOLL_WRITE
);
624 static int ptrace_setoptions(struct task_struct
*child
, unsigned long data
)
628 if (data
& ~(unsigned long)PTRACE_O_MASK
)
631 if (unlikely(data
& PTRACE_O_SUSPEND_SECCOMP
)) {
632 if (!IS_ENABLED(CONFIG_CHECKPOINT_RESTORE
) ||
633 !IS_ENABLED(CONFIG_SECCOMP
))
636 if (!capable(CAP_SYS_ADMIN
))
639 if (seccomp_mode(¤t
->seccomp
) != SECCOMP_MODE_DISABLED
||
640 current
->ptrace
& PT_SUSPEND_SECCOMP
)
644 /* Avoid intermediate state when all opts are cleared */
645 flags
= child
->ptrace
;
646 flags
&= ~(PTRACE_O_MASK
<< PT_OPT_FLAG_SHIFT
);
647 flags
|= (data
<< PT_OPT_FLAG_SHIFT
);
648 child
->ptrace
= flags
;
653 static int ptrace_getsiginfo(struct task_struct
*child
, kernel_siginfo_t
*info
)
658 if (lock_task_sighand(child
, &flags
)) {
660 if (likely(child
->last_siginfo
!= NULL
)) {
661 copy_siginfo(info
, child
->last_siginfo
);
664 unlock_task_sighand(child
, &flags
);
669 static int ptrace_setsiginfo(struct task_struct
*child
, const kernel_siginfo_t
*info
)
674 if (lock_task_sighand(child
, &flags
)) {
676 if (likely(child
->last_siginfo
!= NULL
)) {
677 copy_siginfo(child
->last_siginfo
, info
);
680 unlock_task_sighand(child
, &flags
);
685 static int ptrace_peek_siginfo(struct task_struct
*child
,
689 struct ptrace_peeksiginfo_args arg
;
690 struct sigpending
*pending
;
694 ret
= copy_from_user(&arg
, (void __user
*) addr
,
695 sizeof(struct ptrace_peeksiginfo_args
));
699 if (arg
.flags
& ~PTRACE_PEEKSIGINFO_SHARED
)
700 return -EINVAL
; /* unknown flags */
705 if (arg
.flags
& PTRACE_PEEKSIGINFO_SHARED
)
706 pending
= &child
->signal
->shared_pending
;
708 pending
= &child
->pending
;
710 for (i
= 0; i
< arg
.nr
; ) {
711 kernel_siginfo_t info
;
712 s32 off
= arg
.off
+ i
;
714 spin_lock_irq(&child
->sighand
->siglock
);
715 list_for_each_entry(q
, &pending
->list
, list
) {
717 copy_siginfo(&info
, &q
->info
);
721 spin_unlock_irq(&child
->sighand
->siglock
);
723 if (off
>= 0) /* beyond the end of the list */
727 if (unlikely(in_compat_syscall())) {
728 compat_siginfo_t __user
*uinfo
= compat_ptr(data
);
730 if (copy_siginfo_to_user32(uinfo
, &info
)) {
738 siginfo_t __user
*uinfo
= (siginfo_t __user
*) data
;
740 if (copy_siginfo_to_user(uinfo
, &info
)) {
746 data
+= sizeof(siginfo_t
);
749 if (signal_pending(current
))
761 #ifdef PTRACE_SINGLESTEP
762 #define is_singlestep(request) ((request) == PTRACE_SINGLESTEP)
764 #define is_singlestep(request) 0
767 #ifdef PTRACE_SINGLEBLOCK
768 #define is_singleblock(request) ((request) == PTRACE_SINGLEBLOCK)
770 #define is_singleblock(request) 0
774 #define is_sysemu_singlestep(request) ((request) == PTRACE_SYSEMU_SINGLESTEP)
776 #define is_sysemu_singlestep(request) 0
779 static int ptrace_resume(struct task_struct
*child
, long request
,
784 if (!valid_signal(data
))
787 if (request
== PTRACE_SYSCALL
)
788 set_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
790 clear_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
792 #ifdef TIF_SYSCALL_EMU
793 if (request
== PTRACE_SYSEMU
|| request
== PTRACE_SYSEMU_SINGLESTEP
)
794 set_tsk_thread_flag(child
, TIF_SYSCALL_EMU
);
796 clear_tsk_thread_flag(child
, TIF_SYSCALL_EMU
);
799 if (is_singleblock(request
)) {
800 if (unlikely(!arch_has_block_step()))
802 user_enable_block_step(child
);
803 } else if (is_singlestep(request
) || is_sysemu_singlestep(request
)) {
804 if (unlikely(!arch_has_single_step()))
806 user_enable_single_step(child
);
808 user_disable_single_step(child
);
812 * Change ->exit_code and ->state under siglock to avoid the race
813 * with wait_task_stopped() in between; a non-zero ->exit_code will
814 * wrongly look like another report from tracee.
816 * Note that we need siglock even if ->exit_code == data and/or this
817 * status was not reported yet, the new status must not be cleared by
818 * wait_task_stopped() after resume.
820 * If data == 0 we do not care if wait_task_stopped() reports the old
821 * status and clears the code too; this can't race with the tracee, it
822 * takes siglock after resume.
824 need_siglock
= data
&& !thread_group_empty(current
);
826 spin_lock_irq(&child
->sighand
->siglock
);
827 child
->exit_code
= data
;
828 wake_up_state(child
, __TASK_TRACED
);
830 spin_unlock_irq(&child
->sighand
->siglock
);
835 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
837 static const struct user_regset
*
838 find_regset(const struct user_regset_view
*view
, unsigned int type
)
840 const struct user_regset
*regset
;
843 for (n
= 0; n
< view
->n
; ++n
) {
844 regset
= view
->regsets
+ n
;
845 if (regset
->core_note_type
== type
)
852 static int ptrace_regset(struct task_struct
*task
, int req
, unsigned int type
,
855 const struct user_regset_view
*view
= task_user_regset_view(task
);
856 const struct user_regset
*regset
= find_regset(view
, type
);
859 if (!regset
|| (kiov
->iov_len
% regset
->size
) != 0)
862 regset_no
= regset
- view
->regsets
;
863 kiov
->iov_len
= min(kiov
->iov_len
,
864 (__kernel_size_t
) (regset
->n
* regset
->size
));
866 if (req
== PTRACE_GETREGSET
)
867 return copy_regset_to_user(task
, view
, regset_no
, 0,
868 kiov
->iov_len
, kiov
->iov_base
);
870 return copy_regset_from_user(task
, view
, regset_no
, 0,
871 kiov
->iov_len
, kiov
->iov_base
);
875 * This is declared in linux/regset.h and defined in machine-dependent
876 * code. We put the export here, near the primary machine-neutral use,
877 * to ensure no machine forgets it.
879 EXPORT_SYMBOL_GPL(task_user_regset_view
);
882 int ptrace_request(struct task_struct
*child
, long request
,
883 unsigned long addr
, unsigned long data
)
885 bool seized
= child
->ptrace
& PT_SEIZED
;
887 kernel_siginfo_t siginfo
, *si
;
888 void __user
*datavp
= (void __user
*) data
;
889 unsigned long __user
*datalp
= datavp
;
893 case PTRACE_PEEKTEXT
:
894 case PTRACE_PEEKDATA
:
895 return generic_ptrace_peekdata(child
, addr
, data
);
896 case PTRACE_POKETEXT
:
897 case PTRACE_POKEDATA
:
898 return generic_ptrace_pokedata(child
, addr
, data
);
900 #ifdef PTRACE_OLDSETOPTIONS
901 case PTRACE_OLDSETOPTIONS
:
903 case PTRACE_SETOPTIONS
:
904 ret
= ptrace_setoptions(child
, data
);
906 case PTRACE_GETEVENTMSG
:
907 ret
= put_user(child
->ptrace_message
, datalp
);
910 case PTRACE_PEEKSIGINFO
:
911 ret
= ptrace_peek_siginfo(child
, addr
, data
);
914 case PTRACE_GETSIGINFO
:
915 ret
= ptrace_getsiginfo(child
, &siginfo
);
917 ret
= copy_siginfo_to_user(datavp
, &siginfo
);
920 case PTRACE_SETSIGINFO
:
921 ret
= copy_siginfo_from_user(&siginfo
, datavp
);
923 ret
= ptrace_setsiginfo(child
, &siginfo
);
926 case PTRACE_GETSIGMASK
: {
929 if (addr
!= sizeof(sigset_t
)) {
934 if (test_tsk_restore_sigmask(child
))
935 mask
= &child
->saved_sigmask
;
937 mask
= &child
->blocked
;
939 if (copy_to_user(datavp
, mask
, sizeof(sigset_t
)))
947 case PTRACE_SETSIGMASK
: {
950 if (addr
!= sizeof(sigset_t
)) {
955 if (copy_from_user(&new_set
, datavp
, sizeof(sigset_t
))) {
960 sigdelsetmask(&new_set
, sigmask(SIGKILL
)|sigmask(SIGSTOP
));
963 * Every thread does recalc_sigpending() after resume, so
964 * retarget_shared_pending() and recalc_sigpending() are not
967 spin_lock_irq(&child
->sighand
->siglock
);
968 child
->blocked
= new_set
;
969 spin_unlock_irq(&child
->sighand
->siglock
);
971 clear_tsk_restore_sigmask(child
);
977 case PTRACE_INTERRUPT
:
979 * Stop tracee without any side-effect on signal or job
980 * control. At least one trap is guaranteed to happen
981 * after this request. If @child is already trapped, the
982 * current trap is not disturbed and another trap will
983 * happen after the current trap is ended with PTRACE_CONT.
985 * The actual trap might not be PTRACE_EVENT_STOP trap but
986 * the pending condition is cleared regardless.
988 if (unlikely(!seized
|| !lock_task_sighand(child
, &flags
)))
992 * INTERRUPT doesn't disturb existing trap sans one
993 * exception. If ptracer issued LISTEN for the current
994 * STOP, this INTERRUPT should clear LISTEN and re-trap
997 if (likely(task_set_jobctl_pending(child
, JOBCTL_TRAP_STOP
)))
998 ptrace_signal_wake_up(child
, child
->jobctl
& JOBCTL_LISTENING
);
1000 unlock_task_sighand(child
, &flags
);
1006 * Listen for events. Tracee must be in STOP. It's not
1007 * resumed per-se but is not considered to be in TRACED by
1008 * wait(2) or ptrace(2). If an async event (e.g. group
1009 * stop state change) happens, tracee will enter STOP trap
1010 * again. Alternatively, ptracer can issue INTERRUPT to
1011 * finish listening and re-trap tracee into STOP.
1013 if (unlikely(!seized
|| !lock_task_sighand(child
, &flags
)))
1016 si
= child
->last_siginfo
;
1017 if (likely(si
&& (si
->si_code
>> 8) == PTRACE_EVENT_STOP
)) {
1018 child
->jobctl
|= JOBCTL_LISTENING
;
1020 * If NOTIFY is set, it means event happened between
1021 * start of this trap and now. Trigger re-trap.
1023 if (child
->jobctl
& JOBCTL_TRAP_NOTIFY
)
1024 ptrace_signal_wake_up(child
, true);
1027 unlock_task_sighand(child
, &flags
);
1030 case PTRACE_DETACH
: /* detach a process that was attached. */
1031 ret
= ptrace_detach(child
, data
);
1034 #ifdef CONFIG_BINFMT_ELF_FDPIC
1035 case PTRACE_GETFDPIC
: {
1036 struct mm_struct
*mm
= get_task_mm(child
);
1037 unsigned long tmp
= 0;
1044 case PTRACE_GETFDPIC_EXEC
:
1045 tmp
= mm
->context
.exec_fdpic_loadmap
;
1047 case PTRACE_GETFDPIC_INTERP
:
1048 tmp
= mm
->context
.interp_fdpic_loadmap
;
1055 ret
= put_user(tmp
, datalp
);
1060 #ifdef PTRACE_SINGLESTEP
1061 case PTRACE_SINGLESTEP
:
1063 #ifdef PTRACE_SINGLEBLOCK
1064 case PTRACE_SINGLEBLOCK
:
1066 #ifdef PTRACE_SYSEMU
1068 case PTRACE_SYSEMU_SINGLESTEP
:
1070 case PTRACE_SYSCALL
:
1072 return ptrace_resume(child
, request
, data
);
1075 if (child
->exit_state
) /* already dead */
1077 return ptrace_resume(child
, request
, SIGKILL
);
1079 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
1080 case PTRACE_GETREGSET
:
1081 case PTRACE_SETREGSET
: {
1083 struct iovec __user
*uiov
= datavp
;
1085 if (!access_ok(uiov
, sizeof(*uiov
)))
1088 if (__get_user(kiov
.iov_base
, &uiov
->iov_base
) ||
1089 __get_user(kiov
.iov_len
, &uiov
->iov_len
))
1092 ret
= ptrace_regset(child
, request
, addr
, &kiov
);
1094 ret
= __put_user(kiov
.iov_len
, &uiov
->iov_len
);
1099 case PTRACE_SECCOMP_GET_FILTER
:
1100 ret
= seccomp_get_filter(child
, addr
, datavp
);
1103 case PTRACE_SECCOMP_GET_METADATA
:
1104 ret
= seccomp_get_metadata(child
, addr
, datavp
);
1114 #ifndef arch_ptrace_attach
1115 #define arch_ptrace_attach(child) do { } while (0)
1118 SYSCALL_DEFINE4(ptrace
, long, request
, long, pid
, unsigned long, addr
,
1119 unsigned long, data
)
1121 struct task_struct
*child
;
1124 if (request
== PTRACE_TRACEME
) {
1125 ret
= ptrace_traceme();
1127 arch_ptrace_attach(current
);
1131 child
= find_get_task_by_vpid(pid
);
1137 if (request
== PTRACE_ATTACH
|| request
== PTRACE_SEIZE
) {
1138 ret
= ptrace_attach(child
, request
, addr
, data
);
1140 * Some architectures need to do book-keeping after
1144 arch_ptrace_attach(child
);
1145 goto out_put_task_struct
;
1148 ret
= ptrace_check_attach(child
, request
== PTRACE_KILL
||
1149 request
== PTRACE_INTERRUPT
);
1151 goto out_put_task_struct
;
1153 ret
= arch_ptrace(child
, request
, addr
, data
);
1154 if (ret
|| request
!= PTRACE_DETACH
)
1155 ptrace_unfreeze_traced(child
);
1157 out_put_task_struct
:
1158 put_task_struct(child
);
1163 int generic_ptrace_peekdata(struct task_struct
*tsk
, unsigned long addr
,
1169 copied
= ptrace_access_vm(tsk
, addr
, &tmp
, sizeof(tmp
), FOLL_FORCE
);
1170 if (copied
!= sizeof(tmp
))
1172 return put_user(tmp
, (unsigned long __user
*)data
);
1175 int generic_ptrace_pokedata(struct task_struct
*tsk
, unsigned long addr
,
1180 copied
= ptrace_access_vm(tsk
, addr
, &data
, sizeof(data
),
1181 FOLL_FORCE
| FOLL_WRITE
);
1182 return (copied
== sizeof(data
)) ? 0 : -EIO
;
1185 #if defined CONFIG_COMPAT
1187 int compat_ptrace_request(struct task_struct
*child
, compat_long_t request
,
1188 compat_ulong_t addr
, compat_ulong_t data
)
1190 compat_ulong_t __user
*datap
= compat_ptr(data
);
1191 compat_ulong_t word
;
1192 kernel_siginfo_t siginfo
;
1196 case PTRACE_PEEKTEXT
:
1197 case PTRACE_PEEKDATA
:
1198 ret
= ptrace_access_vm(child
, addr
, &word
, sizeof(word
),
1200 if (ret
!= sizeof(word
))
1203 ret
= put_user(word
, datap
);
1206 case PTRACE_POKETEXT
:
1207 case PTRACE_POKEDATA
:
1208 ret
= ptrace_access_vm(child
, addr
, &data
, sizeof(data
),
1209 FOLL_FORCE
| FOLL_WRITE
);
1210 ret
= (ret
!= sizeof(data
) ? -EIO
: 0);
1213 case PTRACE_GETEVENTMSG
:
1214 ret
= put_user((compat_ulong_t
) child
->ptrace_message
, datap
);
1217 case PTRACE_GETSIGINFO
:
1218 ret
= ptrace_getsiginfo(child
, &siginfo
);
1220 ret
= copy_siginfo_to_user32(
1221 (struct compat_siginfo __user
*) datap
,
1225 case PTRACE_SETSIGINFO
:
1226 ret
= copy_siginfo_from_user32(
1227 &siginfo
, (struct compat_siginfo __user
*) datap
);
1229 ret
= ptrace_setsiginfo(child
, &siginfo
);
1231 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
1232 case PTRACE_GETREGSET
:
1233 case PTRACE_SETREGSET
:
1236 struct compat_iovec __user
*uiov
=
1237 (struct compat_iovec __user
*) datap
;
1241 if (!access_ok(uiov
, sizeof(*uiov
)))
1244 if (__get_user(ptr
, &uiov
->iov_base
) ||
1245 __get_user(len
, &uiov
->iov_len
))
1248 kiov
.iov_base
= compat_ptr(ptr
);
1251 ret
= ptrace_regset(child
, request
, addr
, &kiov
);
1253 ret
= __put_user(kiov
.iov_len
, &uiov
->iov_len
);
1259 ret
= ptrace_request(child
, request
, addr
, data
);
1265 COMPAT_SYSCALL_DEFINE4(ptrace
, compat_long_t
, request
, compat_long_t
, pid
,
1266 compat_long_t
, addr
, compat_long_t
, data
)
1268 struct task_struct
*child
;
1271 if (request
== PTRACE_TRACEME
) {
1272 ret
= ptrace_traceme();
1276 child
= find_get_task_by_vpid(pid
);
1282 if (request
== PTRACE_ATTACH
|| request
== PTRACE_SEIZE
) {
1283 ret
= ptrace_attach(child
, request
, addr
, data
);
1285 * Some architectures need to do book-keeping after
1289 arch_ptrace_attach(child
);
1290 goto out_put_task_struct
;
1293 ret
= ptrace_check_attach(child
, request
== PTRACE_KILL
||
1294 request
== PTRACE_INTERRUPT
);
1296 ret
= compat_arch_ptrace(child
, request
, addr
, data
);
1297 if (ret
|| request
!= PTRACE_DETACH
)
1298 ptrace_unfreeze_traced(child
);
1301 out_put_task_struct
:
1302 put_task_struct(child
);
1306 #endif /* CONFIG_COMPAT */