1 /*-
2 * Copyright (c) 1994, Sean Eric Fagan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by Sean Eric Fagan.
16 * 4. The name of the author may not be used to endorse or promote products
17 * derived from this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD: releng/6.2/sys/kern/sys_process.c 164286 2006-11-14 20:42:41Z cvs2svn $");
34
35 #include "opt_compat.h"
36
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/lock.h>
40 #include <sys/mutex.h>
41 #include <sys/syscallsubr.h>
42 #include <sys/sysproto.h>
43 #include <sys/proc.h>
44 #include <sys/vnode.h>
45 #include <sys/ptrace.h>
46 #include <sys/sx.h>
47 #include <sys/malloc.h>
48 #include <sys/signalvar.h>
49
50 #include <machine/reg.h>
51
52 #include <security/audit/audit.h>
53
54 #include <vm/vm.h>
55 #include <vm/pmap.h>
56 #include <vm/vm_extern.h>
57 #include <vm/vm_map.h>
58 #include <vm/vm_kern.h>
59 #include <vm/vm_object.h>
60 #include <vm/vm_page.h>
61
62 #ifdef COMPAT_IA32
63 #include <sys/procfs.h>
64 #include <machine/fpu.h>
65 #include <compat/ia32/ia32_reg.h>
66
67 extern struct sysentvec ia32_freebsd_sysvec;
68
69 struct ptrace_io_desc32 {
70 int piod_op;
71 u_int32_t piod_offs;
72 u_int32_t piod_addr;
73 u_int32_t piod_len;
74 };
75 #endif
76
77 /*
78 * Functions implemented using PROC_ACTION():
79 *
80 * proc_read_regs(proc, regs)
81 * Get the current user-visible register set from the process
82 * and copy it into the regs structure (<machine/reg.h>).
83 * The process is stopped at the time read_regs is called.
84 *
85 * proc_write_regs(proc, regs)
86 * Update the current register set from the passed in regs
87 * structure. Take care to avoid clobbering special CPU
88 * registers or privileged bits in the PSL.
89 * Depending on the architecture this may have fix-up work to do,
90 * especially if the IAR or PCW are modified.
91 * The process is stopped at the time write_regs is called.
92 *
93 * proc_read_fpregs, proc_write_fpregs
94 * deal with the floating point register set, otherwise as above.
95 *
96 * proc_read_dbregs, proc_write_dbregs
97 * deal with the processor debug register set, otherwise as above.
98 *
99 * proc_sstep(proc)
100 * Arrange for the process to trap after executing a single instruction.
101 */
102
103 #define PROC_ACTION(action) do { \
104 int error; \
105 \
106 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); \
107 if ((td->td_proc->p_sflag & PS_INMEM) == 0) \
108 error = EIO; \
109 else \
110 error = (action); \
111 return (error); \
112 } while(0)
113
114 int
115 proc_read_regs(struct thread *td, struct reg *regs)
116 {
117
118 PROC_ACTION(fill_regs(td, regs));
119 }
120
121 int
122 proc_write_regs(struct thread *td, struct reg *regs)
123 {
124
125 PROC_ACTION(set_regs(td, regs));
126 }
127
128 int
129 proc_read_dbregs(struct thread *td, struct dbreg *dbregs)
130 {
131
132 PROC_ACTION(fill_dbregs(td, dbregs));
133 }
134
135 int
136 proc_write_dbregs(struct thread *td, struct dbreg *dbregs)
137 {
138
139 PROC_ACTION(set_dbregs(td, dbregs));
140 }
141
142 /*
143 * Ptrace doesn't support fpregs at all, and there are no security holes
144 * or translations for fpregs, so we can just copy them.
145 */
146 int
147 proc_read_fpregs(struct thread *td, struct fpreg *fpregs)
148 {
149
150 PROC_ACTION(fill_fpregs(td, fpregs));
151 }
152
153 int
154 proc_write_fpregs(struct thread *td, struct fpreg *fpregs)
155 {
156
157 PROC_ACTION(set_fpregs(td, fpregs));
158 }
159
160 #ifdef COMPAT_IA32
161 /* For 32 bit binaries, we need to expose the 32 bit regs layouts. */
162 int
163 proc_read_regs32(struct thread *td, struct reg32 *regs32)
164 {
165
166 PROC_ACTION(fill_regs32(td, regs32));
167 }
168
169 int
170 proc_write_regs32(struct thread *td, struct reg32 *regs32)
171 {
172
173 PROC_ACTION(set_regs32(td, regs32));
174 }
175
176 int
177 proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
178 {
179
180 PROC_ACTION(fill_dbregs32(td, dbregs32));
181 }
182
183 int
184 proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
185 {
186
187 PROC_ACTION(set_dbregs32(td, dbregs32));
188 }
189
190 int
191 proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
192 {
193
194 PROC_ACTION(fill_fpregs32(td, fpregs32));
195 }
196
197 int
198 proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
199 {
200
201 PROC_ACTION(set_fpregs32(td, fpregs32));
202 }
203 #endif
204
205 int
206 proc_sstep(struct thread *td)
207 {
208
209 PROC_ACTION(ptrace_single_step(td));
210 }
211
212 int
213 proc_rwmem(struct proc *p, struct uio *uio)
214 {
215 vm_map_t map;
216 vm_object_t backing_object, object = NULL;
217 vm_offset_t pageno = 0; /* page number */
218 vm_prot_t reqprot;
219 int error, writing;
220
221 /*
222 * Assert that someone has locked this vmspace. (Should be
223 * curthread but we can't assert that.) This keeps the process
224 * from exiting out from under us until this operation completes.
225 */
226 KASSERT(p->p_lock >= 1, ("%s: process %p (pid %d) not held", __func__,
227 p, p->p_pid));
228
229 /*
230 * The map we want...
231 */
232 map = &p->p_vmspace->vm_map;
233
234 writing = uio->uio_rw == UIO_WRITE;
235 reqprot = writing ? (VM_PROT_WRITE | VM_PROT_OVERRIDE_WRITE) :
236 VM_PROT_READ;
237
238 /*
239 * Only map in one page at a time. We don't have to, but it
240 * makes things easier. This way is trivial - right?
241 */
242 do {
243 vm_map_t tmap;
244 vm_offset_t uva;
245 int page_offset; /* offset into page */
246 vm_map_entry_t out_entry;
247 vm_prot_t out_prot;
248 boolean_t wired;
249 vm_pindex_t pindex;
250 u_int len;
251 vm_page_t m;
252
253 object = NULL;
254
255 uva = (vm_offset_t)uio->uio_offset;
256
257 /*
258 * Get the page number of this segment.
259 */
260 pageno = trunc_page(uva);
261 page_offset = uva - pageno;
262
263 /*
264 * How many bytes to copy
265 */
266 len = min(PAGE_SIZE - page_offset, uio->uio_resid);
267
268 /*
269 * Fault the page on behalf of the process
270 */
271 error = vm_fault(map, pageno, reqprot, VM_FAULT_NORMAL);
272 if (error) {
273 error = EFAULT;
274 break;
275 }
276
277 /*
278 * Now we need to get the page. out_entry, out_prot, wired,
279 * and single_use aren't used. One would think the vm code
280 * would be a *bit* nicer... We use tmap because
281 * vm_map_lookup() can change the map argument.
282 */
283 tmap = map;
284 error = vm_map_lookup(&tmap, pageno, reqprot, &out_entry,
285 &object, &pindex, &out_prot, &wired);
286 if (error) {
287 error = EFAULT;
288 break;
289 }
290 VM_OBJECT_LOCK(object);
291 while ((m = vm_page_lookup(object, pindex)) == NULL &&
292 !writing &&
293 (backing_object = object->backing_object) != NULL) {
294 /*
295 * Allow fallback to backing objects if we are reading.
296 */
297 VM_OBJECT_LOCK(backing_object);
298 pindex += OFF_TO_IDX(object->backing_object_offset);
299 VM_OBJECT_UNLOCK(object);
300 object = backing_object;
301 }
302 VM_OBJECT_UNLOCK(object);
303 if (m == NULL) {
304 vm_map_lookup_done(tmap, out_entry);
305 error = EFAULT;
306 break;
307 }
308
309 /*
310 * Hold the page in memory.
311 */
312 vm_page_lock_queues();
313 vm_page_hold(m);
314 vm_page_unlock_queues();
315
316 /*
317 * We're done with tmap now.
318 */
319 vm_map_lookup_done(tmap, out_entry);
320
321 /*
322 * Now do the i/o move.
323 */
324 error = uiomove_fromphys(&m, page_offset, len, uio);
325
326 /*
327 * Release the page.
328 */
329 vm_page_lock_queues();
330 vm_page_unhold(m);
331 vm_page_unlock_queues();
332
333 } while (error == 0 && uio->uio_resid > 0);
334
335 return (error);
336 }
337
338 /*
339 * Process debugging system call.
340 */
341 #ifndef _SYS_SYSPROTO_H_
342 struct ptrace_args {
343 int req;
344 pid_t pid;
345 caddr_t addr;
346 int data;
347 };
348 #endif
349
350 #ifdef COMPAT_IA32
351 /*
352 * This CPP subterfuge is to try and reduce the number of ifdefs in
353 * the body of the code.
354 * COPYIN(uap->addr, &r.reg, sizeof r.reg);
355 * becomes either:
356 * copyin(uap->addr, &r.reg, sizeof r.reg);
357 * or
358 * copyin(uap->addr, &r.reg32, sizeof r.reg32);
359 * .. except this is done at runtime.
360 */
361 #define COPYIN(u, k, s) wrap32 ? \
362 copyin(u, k ## 32, s ## 32) : \
363 copyin(u, k, s)
364 #define COPYOUT(k, u, s) wrap32 ? \
365 copyout(k ## 32, u, s ## 32) : \
366 copyout(k, u, s)
367 #else
368 #define COPYIN(u, k, s) copyin(u, k, s)
369 #define COPYOUT(k, u, s) copyout(k, u, s)
370 #endif
371 /*
372 * MPSAFE
373 */
374 int
375 ptrace(struct thread *td, struct ptrace_args *uap)
376 {
377 /*
378 * XXX this obfuscation is to reduce stack usage, but the register
379 * structs may be too large to put on the stack anyway.
380 */
381 union {
382 struct ptrace_io_desc piod;
383 struct ptrace_lwpinfo pl;
384 struct dbreg dbreg;
385 struct fpreg fpreg;
386 struct reg reg;
387 #ifdef COMPAT_IA32
388 struct dbreg32 dbreg32;
389 struct fpreg32 fpreg32;
390 struct reg32 reg32;
391 struct ptrace_io_desc32 piod32;
392 #endif
393 } r;
394 void *addr;
395 int error = 0;
396 #ifdef COMPAT_IA32
397 int wrap32 = 0;
398
399 if (td->td_proc->p_sysent == &ia32_freebsd_sysvec)
400 wrap32 = 1;
401 #endif
402 AUDIT_ARG(pid, uap->pid);
403 AUDIT_ARG(cmd, uap->req);
404 AUDIT_ARG(addr, uap->addr);
405 AUDIT_ARG(value, uap->data);
406 addr = &r;
407 switch (uap->req) {
408 case PT_GETREGS:
409 case PT_GETFPREGS:
410 case PT_GETDBREGS:
411 case PT_LWPINFO:
412 break;
413 case PT_SETREGS:
414 error = COPYIN(uap->addr, &r.reg, sizeof r.reg);
415 break;
416 case PT_SETFPREGS:
417 error = COPYIN(uap->addr, &r.fpreg, sizeof r.fpreg);
418 break;
419 case PT_SETDBREGS:
420 error = COPYIN(uap->addr, &r.dbreg, sizeof r.dbreg);
421 break;
422 case PT_IO:
423 error = COPYIN(uap->addr, &r.piod, sizeof r.piod);
424 break;
425 default:
426 addr = uap->addr;
427 break;
428 }
429 if (error)
430 return (error);
431
432 error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data);
433 if (error)
434 return (error);
435
436 switch (uap->req) {
437 case PT_IO:
438 error = COPYOUT(&r.piod, uap->addr, sizeof r.piod);
439 break;
440 case PT_GETREGS:
441 error = COPYOUT(&r.reg, uap->addr, sizeof r.reg);
442 break;
443 case PT_GETFPREGS:
444 error = COPYOUT(&r.fpreg, uap->addr, sizeof r.fpreg);
445 break;
446 case PT_GETDBREGS:
447 error = COPYOUT(&r.dbreg, uap->addr, sizeof r.dbreg);
448 break;
449 case PT_LWPINFO:
450 error = copyout(&r.pl, uap->addr, uap->data);
451 break;
452 }
453
454 return (error);
455 }
456 #undef COPYIN
457 #undef COPYOUT
458
459 #ifdef COMPAT_IA32
460 /*
461 * PROC_READ(regs, td2, addr);
462 * becomes either:
463 * proc_read_regs(td2, addr);
464 * or
465 * proc_read_regs32(td2, addr);
466 * .. except this is done at runtime. There is an additional
467 * complication in that PROC_WRITE disallows 32 bit consumers
468 * from writing to 64 bit address space targets.
469 */
470 #define PROC_READ(w, t, a) wrap32 ? \
471 proc_read_ ## w ## 32(t, a) : \
472 proc_read_ ## w (t, a)
473 #define PROC_WRITE(w, t, a) wrap32 ? \
474 (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \
475 proc_write_ ## w (t, a)
476 #else
477 #define PROC_READ(w, t, a) proc_read_ ## w (t, a)
478 #define PROC_WRITE(w, t, a) proc_write_ ## w (t, a)
479 #endif
480
481 int
482 kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data)
483 {
484 struct iovec iov;
485 struct uio uio;
486 struct proc *curp, *p, *pp;
487 struct thread *td2 = NULL;
488 struct ptrace_io_desc *piod = NULL;
489 struct ptrace_lwpinfo *pl;
490 int error, write, tmp, num;
491 int proctree_locked = 0;
492 lwpid_t tid = 0, *buf;
493 #ifdef COMPAT_IA32
494 int wrap32 = 0, safe = 0;
495 struct ptrace_io_desc32 *piod32 = NULL;
496 #endif
497
498 curp = td->td_proc;
499
500 /* Lock proctree before locking the process. */
501 switch (req) {
502 case PT_TRACE_ME:
503 case PT_ATTACH:
504 case PT_STEP:
505 case PT_CONTINUE:
506 case PT_TO_SCE:
507 case PT_TO_SCX:
508 case PT_SYSCALL:
509 case PT_DETACH:
510 sx_xlock(&proctree_lock);
511 proctree_locked = 1;
512 break;
513 default:
514 break;
515 }
516
517 write = 0;
518 if (req == PT_TRACE_ME) {
519 p = td->td_proc;
520 PROC_LOCK(p);
521 } else {
522 if (pid <= PID_MAX) {
523 if ((p = pfind(pid)) == NULL) {
524 if (proctree_locked)
525 sx_xunlock(&proctree_lock);
526 return (ESRCH);
527 }
528 } else {
529 /* this is slow, should be optimized */
530 sx_slock(&allproc_lock);
531 FOREACH_PROC_IN_SYSTEM(p) {
532 PROC_LOCK(p);
533 mtx_lock_spin(&sched_lock);
534 FOREACH_THREAD_IN_PROC(p, td2) {
535 if (td2->td_tid == pid)
536 break;
537 }
538 mtx_unlock_spin(&sched_lock);
539 if (td2 != NULL)
540 break; /* proc lock held */
541 PROC_UNLOCK(p);
542 }
543 sx_sunlock(&allproc_lock);
544 if (p == NULL) {
545 if (proctree_locked)
546 sx_xunlock(&proctree_lock);
547 return (ESRCH);
548 }
549 tid = pid;
550 pid = p->p_pid;
551 }
552 }
553
554 if ((p->p_flag & P_WEXIT) != 0) {
555 error = ESRCH;
556 goto fail;
557 }
558 AUDIT_ARG(process, p);
559 if ((error = p_cansee(td, p)) != 0)
560 goto fail;
561
562 if ((error = p_candebug(td, p)) != 0)
563 goto fail;
564
565 /*
566 * System processes can't be debugged.
567 */
568 if ((p->p_flag & P_SYSTEM) != 0) {
569 error = EINVAL;
570 goto fail;
571 }
572
573 if (tid == 0) {
574 if ((p->p_flag & P_STOPPED_TRACE) != 0) {
575 KASSERT(p->p_xthread != NULL, ("NULL p_xthread"));
576 td2 = p->p_xthread;
577 } else {
578 td2 = FIRST_THREAD_IN_PROC(p);
579 }
580 tid = td2->td_tid;
581 }
582
583 #ifdef COMPAT_IA32
584 /*
585 * Test if we're a 32 bit client and what the target is.
586 * Set the wrap controls accordingly.
587 */
588 if (td->td_proc->p_sysent == &ia32_freebsd_sysvec) {
589 if (td2->td_proc->p_sysent == &ia32_freebsd_sysvec)
590 safe = 1;
591 wrap32 = 1;
592 }
593 #endif
594 /*
595 * Permissions check
596 */
597 switch (req) {
598 case PT_TRACE_ME:
599 /* Always legal. */
600 break;
601
602 case PT_ATTACH:
603 /* Self */
604 if (p->p_pid == td->td_proc->p_pid) {
605 error = EINVAL;
606 goto fail;
607 }
608
609 /* Already traced */
610 if (p->p_flag & P_TRACED) {
611 error = EBUSY;
612 goto fail;
613 }
614
615 /* Can't trace an ancestor if you're being traced. */
616 if (curp->p_flag & P_TRACED) {
617 for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) {
618 if (pp == p) {
619 error = EINVAL;
620 goto fail;
621 }
622 }
623 }
624
625
626 /* OK */
627 break;
628
629 case PT_CLEARSTEP:
630 /* Allow thread to clear single step for itself */
631 if (td->td_tid == tid)
632 break;
633
634 /* FALLTHROUGH */
635 default:
636 /* not being traced... */
637 if ((p->p_flag & P_TRACED) == 0) {
638 error = EPERM;
639 goto fail;
640 }
641
642 /* not being traced by YOU */
643 if (p->p_pptr != td->td_proc) {
644 error = EBUSY;
645 goto fail;
646 }
647
648 /* not currently stopped */
649 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) == 0 ||
650 p->p_suspcount != p->p_numthreads ||
651 (p->p_flag & P_WAITED) == 0) {
652 error = EBUSY;
653 goto fail;
654 }
655
656 if ((p->p_flag & P_STOPPED_TRACE) == 0) {
657 static int count = 0;
658 if (count++ == 0)
659 printf("P_STOPPED_TRACE not set.\n");
660 }
661
662 /* OK */
663 break;
664 }
665
666 /* Keep this process around until we finish this request. */
667 _PHOLD(p);
668
669 #ifdef FIX_SSTEP
670 /*
671 * Single step fixup ala procfs
672 */
673 FIX_SSTEP(td2);
674 #endif
675
676 /*
677 * Actually do the requests
678 */
679
680 td->td_retval[0] = 0;
681
682 switch (req) {
683 case PT_TRACE_ME:
684 /* set my trace flag and "owner" so it can read/write me */
685 p->p_flag |= P_TRACED;
686 p->p_oppid = p->p_pptr->p_pid;
687 break;
688
689 case PT_ATTACH:
690 /* security check done above */
691 p->p_flag |= P_TRACED;
692 p->p_oppid = p->p_pptr->p_pid;
693 if (p->p_pptr != td->td_proc)
694 proc_reparent(p, td->td_proc);
695 data = SIGSTOP;
696 goto sendsig; /* in PT_CONTINUE below */
697
698 case PT_CLEARSTEP:
699 error = ptrace_clear_single_step(td2);
700 break;
701
702 case PT_SETSTEP:
703 error = ptrace_single_step(td2);
704 break;
705
706 case PT_SUSPEND:
707 mtx_lock_spin(&sched_lock);
708 td2->td_flags |= TDF_DBSUSPEND;
709 mtx_unlock_spin(&sched_lock);
710 break;
711
712 case PT_RESUME:
713 mtx_lock_spin(&sched_lock);
714 td2->td_flags &= ~TDF_DBSUSPEND;
715 mtx_unlock_spin(&sched_lock);
716 break;
717
718 case PT_STEP:
719 case PT_CONTINUE:
720 case PT_TO_SCE:
721 case PT_TO_SCX:
722 case PT_SYSCALL:
723 case PT_DETACH:
724 /* Zero means do not send any signal */
725 if (data < 0 || data > _SIG_MAXSIG) {
726 error = EINVAL;
727 break;
728 }
729
730 switch (req) {
731 case PT_STEP:
732 error = ptrace_single_step(td2);
733 if (error)
734 goto out;
735 break;
736 case PT_TO_SCE:
737 p->p_stops |= S_PT_SCE;
738 break;
739 case PT_TO_SCX:
740 p->p_stops |= S_PT_SCX;
741 break;
742 case PT_SYSCALL:
743 p->p_stops |= S_PT_SCE | S_PT_SCX;
744 break;
745 }
746
747 if (addr != (void *)1) {
748 error = ptrace_set_pc(td2, (u_long)(uintfptr_t)addr);
749 if (error)
750 break;
751 }
752
753 if (req == PT_DETACH) {
754 /* reset process parent */
755 if (p->p_oppid != p->p_pptr->p_pid) {
756 struct proc *pp;
757
758 PROC_UNLOCK(p);
759 pp = pfind(p->p_oppid);
760 if (pp == NULL)
761 pp = initproc;
762 else
763 PROC_UNLOCK(pp);
764 PROC_LOCK(p);
765 proc_reparent(p, pp);
766 if (pp == initproc)
767 p->p_sigparent = SIGCHLD;
768 }
769 p->p_flag &= ~(P_TRACED | P_WAITED);
770 p->p_oppid = 0;
771
772 /* should we send SIGCHLD? */
773 }
774
775 sendsig:
776 if (proctree_locked) {
777 sx_xunlock(&proctree_lock);
778 proctree_locked = 0;
779 }
780 /* deliver or queue signal */
781 mtx_lock_spin(&sched_lock);
782 td2->td_flags &= ~TDF_XSIG;
783 mtx_unlock_spin(&sched_lock);
784 td2->td_xsig = data;
785 p->p_xstat = data;
786 p->p_xthread = NULL;
787 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) != 0) {
788 mtx_lock_spin(&sched_lock);
789 if (req == PT_DETACH) {
790 struct thread *td3;
791 FOREACH_THREAD_IN_PROC(p, td3)
792 td3->td_flags &= ~TDF_DBSUSPEND;
793 }
794 /*
795 * unsuspend all threads, to not let a thread run,
796 * you should use PT_SUSPEND to suspend it before
797 * continuing process.
798 */
799 mtx_unlock_spin(&sched_lock);
800 thread_continued(p);
801 p->p_flag &= ~(P_STOPPED_TRACE|P_STOPPED_SIG|P_WAITED);
802 mtx_lock_spin(&sched_lock);
803 thread_unsuspend(p);
804 mtx_unlock_spin(&sched_lock);
805 }
806
807 if (data)
808 psignal(p, data);
809
810 break;
811
812 case PT_WRITE_I:
813 case PT_WRITE_D:
814 write = 1;
815 /* FALLTHROUGH */
816 case PT_READ_I:
817 case PT_READ_D:
818 PROC_UNLOCK(p);
819 tmp = 0;
820 /* write = 0 set above */
821 iov.iov_base = write ? (caddr_t)&data : (caddr_t)&tmp;
822 iov.iov_len = sizeof(int);
823 uio.uio_iov = &iov;
824 uio.uio_iovcnt = 1;
825 uio.uio_offset = (off_t)(uintptr_t)addr;
826 uio.uio_resid = sizeof(int);
827 uio.uio_segflg = UIO_SYSSPACE; /* i.e.: the uap */
828 uio.uio_rw = write ? UIO_WRITE : UIO_READ;
829 uio.uio_td = td;
830 error = proc_rwmem(p, &uio);
831 if (uio.uio_resid != 0) {
832 /*
833 * XXX proc_rwmem() doesn't currently return ENOSPC,
834 * so I think write() can bogusly return 0.
835 * XXX what happens for short writes? We don't want
836 * to write partial data.
837 * XXX proc_rwmem() returns EPERM for other invalid
838 * addresses. Convert this to EINVAL. Does this
839 * clobber returns of EPERM for other reasons?
840 */
841 if (error == 0 || error == ENOSPC || error == EPERM)
842 error = EINVAL; /* EOF */
843 }
844 if (!write)
845 td->td_retval[0] = tmp;
846 PROC_LOCK(p);
847 break;
848
849 case PT_IO:
850 #ifdef COMPAT_IA32
851 if (wrap32) {
852 piod32 = addr;
853 iov.iov_base = (void *)(uintptr_t)piod32->piod_addr;
854 iov.iov_len = piod32->piod_len;
855 uio.uio_offset = (off_t)(uintptr_t)piod32->piod_offs;
856 uio.uio_resid = piod32->piod_len;
857 } else
858 #endif
859 {
860 piod = addr;
861 iov.iov_base = piod->piod_addr;
862 iov.iov_len = piod->piod_len;
863 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs;
864 uio.uio_resid = piod->piod_len;
865 }
866 uio.uio_iov = &iov;
867 uio.uio_iovcnt = 1;
868 uio.uio_segflg = UIO_USERSPACE;
869 uio.uio_td = td;
870 #ifdef COMPAT_IA32
871 tmp = wrap32 ? piod32->piod_op : piod->piod_op;
872 #else
873 tmp = piod->piod_op;
874 #endif
875 switch (tmp) {
876 case PIOD_READ_D:
877 case PIOD_READ_I:
878 uio.uio_rw = UIO_READ;
879 break;
880 case PIOD_WRITE_D:
881 case PIOD_WRITE_I:
882 uio.uio_rw = UIO_WRITE;
883 break;
884 default:
885 error = EINVAL;
886 goto out;
887 }
888 PROC_UNLOCK(p);
889 error = proc_rwmem(p, &uio);
890 #ifdef COMPAT_IA32
891 if (wrap32)
892 piod32->piod_len -= uio.uio_resid;
893 else
894 #endif
895 piod->piod_len -= uio.uio_resid;
896 PROC_LOCK(p);
897 break;
898
899 case PT_KILL:
900 data = SIGKILL;
901 goto sendsig; /* in PT_CONTINUE above */
902
903 case PT_SETREGS:
904 error = PROC_WRITE(regs, td2, addr);
905 break;
906
907 case PT_GETREGS:
908 error = PROC_READ(regs, td2, addr);
909 break;
910
911 case PT_SETFPREGS:
912 error = PROC_WRITE(fpregs, td2, addr);
913 break;
914
915 case PT_GETFPREGS:
916 error = PROC_READ(fpregs, td2, addr);
917 break;
918
919 case PT_SETDBREGS:
920 error = PROC_WRITE(dbregs, td2, addr);
921 break;
922
923 case PT_GETDBREGS:
924 error = PROC_READ(dbregs, td2, addr);
925 break;
926
927 case PT_LWPINFO:
928 if (data <= 0 || data > sizeof(*pl)) {
929 error = EINVAL;
930 break;
931 }
932 pl = addr;
933 pl->pl_lwpid = td2->td_tid;
934 if (td2->td_flags & TDF_XSIG)
935 pl->pl_event = PL_EVENT_SIGNAL;
936 else
937 pl->pl_event = 0;
938 if (td2->td_pflags & TDP_SA) {
939 pl->pl_flags = PL_FLAG_SA;
940 if (td2->td_upcall && !TD_CAN_UNBIND(td2))
941 pl->pl_flags |= PL_FLAG_BOUND;
942 } else {
943 pl->pl_flags = 0;
944 }
945 pl->pl_sigmask = td2->td_sigmask;
946 pl->pl_siglist = td2->td_siglist;
947 break;
948
949 case PT_GETNUMLWPS:
950 td->td_retval[0] = p->p_numthreads;
951 break;
952
953 case PT_GETLWPLIST:
954 if (data <= 0) {
955 error = EINVAL;
956 break;
957 }
958 num = imin(p->p_numthreads, data);
959 PROC_UNLOCK(p);
960 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK);
961 tmp = 0;
962 PROC_LOCK(p);
963 mtx_lock_spin(&sched_lock);
964 FOREACH_THREAD_IN_PROC(p, td2) {
965 if (tmp >= num)
966 break;
967 buf[tmp++] = td2->td_tid;
968 }
969 mtx_unlock_spin(&sched_lock);
970 PROC_UNLOCK(p);
971 error = copyout(buf, addr, tmp * sizeof(lwpid_t));
972 free(buf, M_TEMP);
973 if (!error)
974 td->td_retval[0] = tmp;
975 PROC_LOCK(p);
976 break;
977
978 default:
979 #ifdef __HAVE_PTRACE_MACHDEP
980 if (req >= PT_FIRSTMACH) {
981 PROC_UNLOCK(p);
982 error = cpu_ptrace(td2, req, addr, data);
983 PROC_LOCK(p);
984 } else
985 #endif
986 /* Unknown request. */
987 error = EINVAL;
988 break;
989 }
990
991 out:
992 /* Drop our hold on this process now that the request has completed. */
993 _PRELE(p);
994 fail:
995 PROC_UNLOCK(p);
996 if (proctree_locked)
997 sx_xunlock(&proctree_lock);
998 return (error);
999 }
1000 #undef PROC_READ
1001 #undef PROC_WRITE
1002
1003 /*
1004 * Stop a process because of a debugging event;
1005 * stay stopped until p->p_step is cleared
1006 * (cleared by PIOCCONT in procfs).
1007 */
1008 void
1009 stopevent(struct proc *p, unsigned int event, unsigned int val)
1010 {
1011
1012 PROC_LOCK_ASSERT(p, MA_OWNED);
1013 p->p_step = 1;
1014 do {
1015 p->p_xstat = val;
1016 p->p_xthread = NULL;
1017 p->p_stype = event; /* Which event caused the stop? */
1018 wakeup(&p->p_stype); /* Wake up any PIOCWAIT'ing procs */
1019 msleep(&p->p_step, &p->p_mtx, PWAIT, "stopevent", 0);
1020 } while (p->p_step);
1021 }
Cache object: 0a6f49a0d0b0cbdbb9db0faf3dacfdd4
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