1 /*-
2 * SPDX-License-Identifier: BSD-4-Clause
3 *
4 * Copyright (c) 1994, Sean Eric Fagan
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by Sean Eric Fagan.
18 * 4. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34 #include <sys/cdefs.h>
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/ktr.h>
38 #include <sys/limits.h>
39 #include <sys/lock.h>
40 #include <sys/mman.h>
41 #include <sys/mutex.h>
42 #include <sys/reg.h>
43 #include <sys/syscallsubr.h>
44 #include <sys/sysent.h>
45 #include <sys/sysproto.h>
46 #include <sys/priv.h>
47 #include <sys/proc.h>
48 #include <sys/vnode.h>
49 #include <sys/ptrace.h>
50 #include <sys/rwlock.h>
51 #include <sys/sx.h>
52 #include <sys/malloc.h>
53 #include <sys/signalvar.h>
54 #include <sys/caprights.h>
55 #include <sys/filedesc.h>
56
57 #include <security/audit/audit.h>
58
59 #include <vm/vm.h>
60 #include <vm/pmap.h>
61 #include <vm/vm_extern.h>
62 #include <vm/vm_map.h>
63 #include <vm/vm_kern.h>
64 #include <vm/vm_object.h>
65 #include <vm/vm_page.h>
66 #include <vm/vm_param.h>
67
68 #ifdef COMPAT_FREEBSD32
69 #include <sys/procfs.h>
70 #endif
71
72 /* Assert it's safe to unlock a process, e.g. to allocate working memory */
73 #define PROC_ASSERT_TRACEREQ(p) MPASS(((p)->p_flag2 & P2_PTRACEREQ) != 0)
74
75 /*
76 * Functions implemented using PROC_ACTION():
77 *
78 * proc_read_regs(proc, regs)
79 * Get the current user-visible register set from the process
80 * and copy it into the regs structure (<machine/reg.h>).
81 * The process is stopped at the time read_regs is called.
82 *
83 * proc_write_regs(proc, regs)
84 * Update the current register set from the passed in regs
85 * structure. Take care to avoid clobbering special CPU
86 * registers or privileged bits in the PSL.
87 * Depending on the architecture this may have fix-up work to do,
88 * especially if the IAR or PCW are modified.
89 * The process is stopped at the time write_regs is called.
90 *
91 * proc_read_fpregs, proc_write_fpregs
92 * deal with the floating point register set, otherwise as above.
93 *
94 * proc_read_dbregs, proc_write_dbregs
95 * deal with the processor debug register set, otherwise as above.
96 *
97 * proc_sstep(proc)
98 * Arrange for the process to trap after executing a single instruction.
99 */
100
101 #define PROC_ACTION(action) do { \
102 int error; \
103 \
104 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); \
105 if ((td->td_proc->p_flag & P_INMEM) == 0) \
106 error = EIO; \
107 else \
108 error = (action); \
109 return (error); \
110 } while (0)
111
112 int
proc_read_regs(struct thread * td,struct reg * regs)113 proc_read_regs(struct thread *td, struct reg *regs)
114 {
115
116 PROC_ACTION(fill_regs(td, regs));
117 }
118
119 int
proc_write_regs(struct thread * td,struct reg * regs)120 proc_write_regs(struct thread *td, struct reg *regs)
121 {
122
123 PROC_ACTION(set_regs(td, regs));
124 }
125
126 int
proc_read_dbregs(struct thread * td,struct dbreg * dbregs)127 proc_read_dbregs(struct thread *td, struct dbreg *dbregs)
128 {
129
130 PROC_ACTION(fill_dbregs(td, dbregs));
131 }
132
133 int
proc_write_dbregs(struct thread * td,struct dbreg * dbregs)134 proc_write_dbregs(struct thread *td, struct dbreg *dbregs)
135 {
136
137 PROC_ACTION(set_dbregs(td, dbregs));
138 }
139
140 /*
141 * Ptrace doesn't support fpregs at all, and there are no security holes
142 * or translations for fpregs, so we can just copy them.
143 */
144 int
proc_read_fpregs(struct thread * td,struct fpreg * fpregs)145 proc_read_fpregs(struct thread *td, struct fpreg *fpregs)
146 {
147
148 PROC_ACTION(fill_fpregs(td, fpregs));
149 }
150
151 int
proc_write_fpregs(struct thread * td,struct fpreg * fpregs)152 proc_write_fpregs(struct thread *td, struct fpreg *fpregs)
153 {
154
155 PROC_ACTION(set_fpregs(td, fpregs));
156 }
157
158 static struct regset *
proc_find_regset(struct thread * td,int note)159 proc_find_regset(struct thread *td, int note)
160 {
161 struct regset **regsetp, **regset_end, *regset;
162 struct sysentvec *sv;
163
164 sv = td->td_proc->p_sysent;
165 regsetp = sv->sv_regset_begin;
166 if (regsetp == NULL)
167 return (NULL);
168 regset_end = sv->sv_regset_end;
169 MPASS(regset_end != NULL);
170 for (; regsetp < regset_end; regsetp++) {
171 regset = *regsetp;
172 if (regset->note != note)
173 continue;
174
175 return (regset);
176 }
177
178 return (NULL);
179 }
180
181 static int
proc_read_regset(struct thread * td,int note,struct iovec * iov)182 proc_read_regset(struct thread *td, int note, struct iovec *iov)
183 {
184 struct regset *regset;
185 struct proc *p;
186 void *buf;
187 size_t size;
188 int error;
189
190 regset = proc_find_regset(td, note);
191 if (regset == NULL)
192 return (EINVAL);
193
194 if (regset->get == NULL)
195 return (EINVAL);
196
197 size = regset->size;
198 /*
199 * The regset is dynamically sized, e.g. the size could change
200 * depending on the hardware, or may have a per-thread size.
201 */
202 if (size == 0) {
203 if (!regset->get(regset, td, NULL, &size))
204 return (EINVAL);
205 }
206
207 if (iov->iov_base == NULL) {
208 iov->iov_len = size;
209 if (iov->iov_len == 0)
210 return (EINVAL);
211
212 return (0);
213 }
214
215 /* The length is wrong, return an error */
216 if (iov->iov_len != size)
217 return (EINVAL);
218
219 error = 0;
220 p = td->td_proc;
221
222 /* Drop the proc lock while allocating the temp buffer */
223 PROC_ASSERT_TRACEREQ(p);
224 PROC_UNLOCK(p);
225 buf = malloc(size, M_TEMP, M_WAITOK);
226 PROC_LOCK(p);
227
228 if (!regset->get(regset, td, buf, &size)) {
229 error = EINVAL;
230 } else {
231 KASSERT(size == regset->size || regset->size == 0,
232 ("%s: Getter function changed the size", __func__));
233
234 iov->iov_len = size;
235 PROC_UNLOCK(p);
236 error = copyout(buf, iov->iov_base, size);
237 PROC_LOCK(p);
238 }
239
240 free(buf, M_TEMP);
241
242 return (error);
243 }
244
245 static int
proc_write_regset(struct thread * td,int note,struct iovec * iov)246 proc_write_regset(struct thread *td, int note, struct iovec *iov)
247 {
248 struct regset *regset;
249 struct proc *p;
250 void *buf;
251 size_t size;
252 int error;
253
254 regset = proc_find_regset(td, note);
255 if (regset == NULL)
256 return (EINVAL);
257
258 size = regset->size;
259 /*
260 * The regset is dynamically sized, e.g. the size could change
261 * depending on the hardware, or may have a per-thread size.
262 */
263 if (size == 0) {
264 if (!regset->get(regset, td, NULL, &size))
265 return (EINVAL);
266 }
267
268 /* The length is wrong, return an error */
269 if (iov->iov_len != size)
270 return (EINVAL);
271
272 if (regset->set == NULL)
273 return (EINVAL);
274
275 p = td->td_proc;
276
277 /* Drop the proc lock while allocating the temp buffer */
278 PROC_ASSERT_TRACEREQ(p);
279 PROC_UNLOCK(p);
280 buf = malloc(size, M_TEMP, M_WAITOK);
281 error = copyin(iov->iov_base, buf, size);
282 PROC_LOCK(p);
283
284 if (error == 0) {
285 if (!regset->set(regset, td, buf, size)) {
286 error = EINVAL;
287 }
288 }
289
290 free(buf, M_TEMP);
291
292 return (error);
293 }
294
295 #ifdef COMPAT_FREEBSD32
296 /* For 32 bit binaries, we need to expose the 32 bit regs layouts. */
297 int
proc_read_regs32(struct thread * td,struct reg32 * regs32)298 proc_read_regs32(struct thread *td, struct reg32 *regs32)
299 {
300
301 PROC_ACTION(fill_regs32(td, regs32));
302 }
303
304 int
proc_write_regs32(struct thread * td,struct reg32 * regs32)305 proc_write_regs32(struct thread *td, struct reg32 *regs32)
306 {
307
308 PROC_ACTION(set_regs32(td, regs32));
309 }
310
311 int
proc_read_dbregs32(struct thread * td,struct dbreg32 * dbregs32)312 proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
313 {
314
315 PROC_ACTION(fill_dbregs32(td, dbregs32));
316 }
317
318 int
proc_write_dbregs32(struct thread * td,struct dbreg32 * dbregs32)319 proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
320 {
321
322 PROC_ACTION(set_dbregs32(td, dbregs32));
323 }
324
325 int
proc_read_fpregs32(struct thread * td,struct fpreg32 * fpregs32)326 proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
327 {
328
329 PROC_ACTION(fill_fpregs32(td, fpregs32));
330 }
331
332 int
proc_write_fpregs32(struct thread * td,struct fpreg32 * fpregs32)333 proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
334 {
335
336 PROC_ACTION(set_fpregs32(td, fpregs32));
337 }
338 #endif
339
340 int
proc_sstep(struct thread * td)341 proc_sstep(struct thread *td)
342 {
343
344 PROC_ACTION(ptrace_single_step(td));
345 }
346
347 int
proc_rwmem(struct proc * p,struct uio * uio)348 proc_rwmem(struct proc *p, struct uio *uio)
349 {
350 vm_map_t map;
351 vm_offset_t pageno; /* page number */
352 vm_prot_t reqprot;
353 int error, fault_flags, page_offset, writing;
354
355 /*
356 * Make sure that the process' vmspace remains live.
357 */
358 if (p != curproc)
359 PROC_ASSERT_HELD(p);
360 PROC_LOCK_ASSERT(p, MA_NOTOWNED);
361
362 /*
363 * The map we want...
364 */
365 map = &p->p_vmspace->vm_map;
366
367 /*
368 * If we are writing, then we request vm_fault() to create a private
369 * copy of each page. Since these copies will not be writeable by the
370 * process, we must explicitly request that they be dirtied.
371 */
372 writing = uio->uio_rw == UIO_WRITE;
373 reqprot = writing ? VM_PROT_COPY | VM_PROT_READ : VM_PROT_READ;
374 fault_flags = writing ? VM_FAULT_DIRTY : VM_FAULT_NORMAL;
375
376 /*
377 * Only map in one page at a time. We don't have to, but it
378 * makes things easier. This way is trivial - right?
379 */
380 do {
381 vm_offset_t uva;
382 u_int len;
383 vm_page_t m;
384
385 uva = (vm_offset_t)uio->uio_offset;
386
387 /*
388 * Get the page number of this segment.
389 */
390 pageno = trunc_page(uva);
391 page_offset = uva - pageno;
392
393 /*
394 * How many bytes to copy
395 */
396 len = MIN(PAGE_SIZE - page_offset, uio->uio_resid);
397
398 /*
399 * Fault and hold the page on behalf of the process.
400 */
401 error = vm_fault(map, pageno, reqprot, fault_flags, &m);
402 if (error != KERN_SUCCESS) {
403 if (error == KERN_RESOURCE_SHORTAGE)
404 error = ENOMEM;
405 else
406 error = EFAULT;
407 break;
408 }
409
410 /*
411 * Now do the i/o move.
412 */
413 error = uiomove_fromphys(&m, page_offset, len, uio);
414
415 /* Make the I-cache coherent for breakpoints. */
416 if (writing && error == 0) {
417 vm_map_lock_read(map);
418 if (vm_map_check_protection(map, pageno, pageno +
419 PAGE_SIZE, VM_PROT_EXECUTE))
420 vm_sync_icache(map, uva, len);
421 vm_map_unlock_read(map);
422 }
423
424 /*
425 * Release the page.
426 */
427 vm_page_unwire(m, PQ_ACTIVE);
428
429 } while (error == 0 && uio->uio_resid > 0);
430
431 return (error);
432 }
433
434 static ssize_t
proc_iop(struct thread * td,struct proc * p,vm_offset_t va,void * buf,size_t len,enum uio_rw rw)435 proc_iop(struct thread *td, struct proc *p, vm_offset_t va, void *buf,
436 size_t len, enum uio_rw rw)
437 {
438 struct iovec iov;
439 struct uio uio;
440 ssize_t slen;
441
442 MPASS(len < SSIZE_MAX);
443 slen = (ssize_t)len;
444
445 iov.iov_base = (caddr_t)buf;
446 iov.iov_len = len;
447 uio.uio_iov = &iov;
448 uio.uio_iovcnt = 1;
449 uio.uio_offset = va;
450 uio.uio_resid = slen;
451 uio.uio_segflg = UIO_SYSSPACE;
452 uio.uio_rw = rw;
453 uio.uio_td = td;
454 proc_rwmem(p, &uio);
455 if (uio.uio_resid == slen)
456 return (-1);
457 return (slen - uio.uio_resid);
458 }
459
460 ssize_t
proc_readmem(struct thread * td,struct proc * p,vm_offset_t va,void * buf,size_t len)461 proc_readmem(struct thread *td, struct proc *p, vm_offset_t va, void *buf,
462 size_t len)
463 {
464
465 return (proc_iop(td, p, va, buf, len, UIO_READ));
466 }
467
468 ssize_t
proc_writemem(struct thread * td,struct proc * p,vm_offset_t va,void * buf,size_t len)469 proc_writemem(struct thread *td, struct proc *p, vm_offset_t va, void *buf,
470 size_t len)
471 {
472
473 return (proc_iop(td, p, va, buf, len, UIO_WRITE));
474 }
475
476 static int
ptrace_vm_entry(struct thread * td,struct proc * p,struct ptrace_vm_entry * pve)477 ptrace_vm_entry(struct thread *td, struct proc *p, struct ptrace_vm_entry *pve)
478 {
479 struct vattr vattr;
480 vm_map_t map;
481 vm_map_entry_t entry;
482 vm_object_t obj, tobj, lobj;
483 struct vmspace *vm;
484 struct vnode *vp;
485 char *freepath, *fullpath;
486 u_int pathlen;
487 int error, index;
488
489 error = 0;
490 obj = NULL;
491
492 vm = vmspace_acquire_ref(p);
493 map = &vm->vm_map;
494 vm_map_lock_read(map);
495
496 do {
497 KASSERT((map->header.eflags & MAP_ENTRY_IS_SUB_MAP) == 0,
498 ("Submap in map header"));
499 index = 0;
500 VM_MAP_ENTRY_FOREACH(entry, map) {
501 if (index >= pve->pve_entry &&
502 (entry->eflags & MAP_ENTRY_IS_SUB_MAP) == 0)
503 break;
504 index++;
505 }
506 if (index < pve->pve_entry) {
507 error = EINVAL;
508 break;
509 }
510 if (entry == &map->header) {
511 error = ENOENT;
512 break;
513 }
514
515 /* We got an entry. */
516 pve->pve_entry = index + 1;
517 pve->pve_timestamp = map->timestamp;
518 pve->pve_start = entry->start;
519 pve->pve_end = entry->end - 1;
520 pve->pve_offset = entry->offset;
521 pve->pve_prot = entry->protection |
522 PROT_MAX(entry->max_protection);
523
524 /* Backing object's path needed? */
525 if (pve->pve_pathlen == 0)
526 break;
527
528 pathlen = pve->pve_pathlen;
529 pve->pve_pathlen = 0;
530
531 obj = entry->object.vm_object;
532 if (obj != NULL)
533 VM_OBJECT_RLOCK(obj);
534 } while (0);
535
536 vm_map_unlock_read(map);
537
538 pve->pve_fsid = VNOVAL;
539 pve->pve_fileid = VNOVAL;
540
541 if (error == 0 && obj != NULL) {
542 lobj = obj;
543 for (tobj = obj; tobj != NULL; tobj = tobj->backing_object) {
544 if (tobj != obj)
545 VM_OBJECT_RLOCK(tobj);
546 if (lobj != obj)
547 VM_OBJECT_RUNLOCK(lobj);
548 lobj = tobj;
549 pve->pve_offset += tobj->backing_object_offset;
550 }
551 vp = vm_object_vnode(lobj);
552 if (vp != NULL)
553 vref(vp);
554 if (lobj != obj)
555 VM_OBJECT_RUNLOCK(lobj);
556 VM_OBJECT_RUNLOCK(obj);
557
558 if (vp != NULL) {
559 freepath = NULL;
560 fullpath = NULL;
561 vn_fullpath(vp, &fullpath, &freepath);
562 vn_lock(vp, LK_SHARED | LK_RETRY);
563 if (VOP_GETATTR(vp, &vattr, td->td_ucred) == 0) {
564 pve->pve_fileid = vattr.va_fileid;
565 pve->pve_fsid = vattr.va_fsid;
566 }
567 vput(vp);
568
569 if (fullpath != NULL) {
570 pve->pve_pathlen = strlen(fullpath) + 1;
571 if (pve->pve_pathlen <= pathlen) {
572 error = copyout(fullpath, pve->pve_path,
573 pve->pve_pathlen);
574 } else
575 error = ENAMETOOLONG;
576 }
577 if (freepath != NULL)
578 free(freepath, M_TEMP);
579 }
580 }
581 vmspace_free(vm);
582 if (error == 0)
583 CTR3(KTR_PTRACE, "PT_VM_ENTRY: pid %d, entry %d, start %p",
584 p->p_pid, pve->pve_entry, pve->pve_start);
585
586 return (error);
587 }
588
589 /*
590 * Process debugging system call.
591 */
592 #ifndef _SYS_SYSPROTO_H_
593 struct ptrace_args {
594 int req;
595 pid_t pid;
596 caddr_t addr;
597 int data;
598 };
599 #endif
600
601 int
sys_ptrace(struct thread * td,struct ptrace_args * uap)602 sys_ptrace(struct thread *td, struct ptrace_args *uap)
603 {
604 /*
605 * XXX this obfuscation is to reduce stack usage, but the register
606 * structs may be too large to put on the stack anyway.
607 */
608 union {
609 struct ptrace_io_desc piod;
610 struct ptrace_lwpinfo pl;
611 struct ptrace_vm_entry pve;
612 struct ptrace_coredump pc;
613 struct ptrace_sc_remote sr;
614 struct dbreg dbreg;
615 struct fpreg fpreg;
616 struct reg reg;
617 struct iovec vec;
618 syscallarg_t args[nitems(td->td_sa.args)];
619 struct ptrace_sc_ret psr;
620 int ptevents;
621 } r;
622 syscallarg_t pscr_args[nitems(td->td_sa.args)];
623 void *addr;
624 int error;
625
626 if (!allow_ptrace)
627 return (ENOSYS);
628 error = 0;
629
630 AUDIT_ARG_PID(uap->pid);
631 AUDIT_ARG_CMD(uap->req);
632 AUDIT_ARG_VALUE(uap->data);
633 addr = &r;
634 switch (uap->req) {
635 case PT_GET_EVENT_MASK:
636 case PT_LWPINFO:
637 case PT_GET_SC_ARGS:
638 case PT_GET_SC_RET:
639 break;
640 case PT_GETREGS:
641 bzero(&r.reg, sizeof(r.reg));
642 break;
643 case PT_GETFPREGS:
644 bzero(&r.fpreg, sizeof(r.fpreg));
645 break;
646 case PT_GETDBREGS:
647 bzero(&r.dbreg, sizeof(r.dbreg));
648 break;
649 case PT_GETREGSET:
650 case PT_SETREGSET:
651 error = copyin(uap->addr, &r.vec, sizeof(r.vec));
652 break;
653 case PT_SETREGS:
654 error = copyin(uap->addr, &r.reg, sizeof(r.reg));
655 break;
656 case PT_SETFPREGS:
657 error = copyin(uap->addr, &r.fpreg, sizeof(r.fpreg));
658 break;
659 case PT_SETDBREGS:
660 error = copyin(uap->addr, &r.dbreg, sizeof(r.dbreg));
661 break;
662 case PT_SET_EVENT_MASK:
663 if (uap->data != sizeof(r.ptevents))
664 error = EINVAL;
665 else
666 error = copyin(uap->addr, &r.ptevents, uap->data);
667 break;
668 case PT_IO:
669 error = copyin(uap->addr, &r.piod, sizeof(r.piod));
670 break;
671 case PT_VM_ENTRY:
672 error = copyin(uap->addr, &r.pve, sizeof(r.pve));
673 break;
674 case PT_COREDUMP:
675 if (uap->data != sizeof(r.pc))
676 error = EINVAL;
677 else
678 error = copyin(uap->addr, &r.pc, uap->data);
679 break;
680 case PT_SC_REMOTE:
681 if (uap->data != sizeof(r.sr)) {
682 error = EINVAL;
683 break;
684 }
685 error = copyin(uap->addr, &r.sr, uap->data);
686 if (error != 0)
687 break;
688 if (r.sr.pscr_nargs > nitems(td->td_sa.args)) {
689 error = EINVAL;
690 break;
691 }
692 error = copyin(r.sr.pscr_args, pscr_args,
693 sizeof(u_long) * r.sr.pscr_nargs);
694 if (error != 0)
695 break;
696 r.sr.pscr_args = pscr_args;
697 break;
698 default:
699 addr = uap->addr;
700 break;
701 }
702 if (error)
703 return (error);
704
705 error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data);
706 if (error)
707 return (error);
708
709 switch (uap->req) {
710 case PT_VM_ENTRY:
711 error = copyout(&r.pve, uap->addr, sizeof(r.pve));
712 break;
713 case PT_IO:
714 error = copyout(&r.piod, uap->addr, sizeof(r.piod));
715 break;
716 case PT_GETREGS:
717 error = copyout(&r.reg, uap->addr, sizeof(r.reg));
718 break;
719 case PT_GETFPREGS:
720 error = copyout(&r.fpreg, uap->addr, sizeof(r.fpreg));
721 break;
722 case PT_GETDBREGS:
723 error = copyout(&r.dbreg, uap->addr, sizeof(r.dbreg));
724 break;
725 case PT_GETREGSET:
726 error = copyout(&r.vec, uap->addr, sizeof(r.vec));
727 break;
728 case PT_GET_EVENT_MASK:
729 /* NB: The size in uap->data is validated in kern_ptrace(). */
730 error = copyout(&r.ptevents, uap->addr, uap->data);
731 break;
732 case PT_LWPINFO:
733 /* NB: The size in uap->data is validated in kern_ptrace(). */
734 error = copyout(&r.pl, uap->addr, uap->data);
735 break;
736 case PT_GET_SC_ARGS:
737 error = copyout(r.args, uap->addr, MIN(uap->data,
738 sizeof(r.args)));
739 break;
740 case PT_GET_SC_RET:
741 error = copyout(&r.psr, uap->addr, MIN(uap->data,
742 sizeof(r.psr)));
743 break;
744 case PT_SC_REMOTE:
745 error = copyout(&r.sr.pscr_ret, uap->addr +
746 offsetof(struct ptrace_sc_remote, pscr_ret),
747 sizeof(r.sr.pscr_ret));
748 break;
749 }
750
751 return (error);
752 }
753
754 #ifdef COMPAT_FREEBSD32
755 /*
756 * PROC_READ(regs, td2, addr);
757 * becomes either:
758 * proc_read_regs(td2, addr);
759 * or
760 * proc_read_regs32(td2, addr);
761 * .. except this is done at runtime. There is an additional
762 * complication in that PROC_WRITE disallows 32 bit consumers
763 * from writing to 64 bit address space targets.
764 */
765 #define PROC_READ(w, t, a) wrap32 ? \
766 proc_read_ ## w ## 32(t, a) : \
767 proc_read_ ## w (t, a)
768 #define PROC_WRITE(w, t, a) wrap32 ? \
769 (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \
770 proc_write_ ## w (t, a)
771 #else
772 #define PROC_READ(w, t, a) proc_read_ ## w (t, a)
773 #define PROC_WRITE(w, t, a) proc_write_ ## w (t, a)
774 #endif
775
776 void
proc_set_traced(struct proc * p,bool stop)777 proc_set_traced(struct proc *p, bool stop)
778 {
779
780 sx_assert(&proctree_lock, SX_XLOCKED);
781 PROC_LOCK_ASSERT(p, MA_OWNED);
782 p->p_flag |= P_TRACED;
783 if (stop)
784 p->p_flag2 |= P2_PTRACE_FSTP;
785 p->p_ptevents = PTRACE_DEFAULT;
786 }
787
788 void
ptrace_unsuspend(struct proc * p)789 ptrace_unsuspend(struct proc *p)
790 {
791 PROC_LOCK_ASSERT(p, MA_OWNED);
792
793 PROC_SLOCK(p);
794 p->p_flag &= ~(P_STOPPED_TRACE | P_STOPPED_SIG | P_WAITED);
795 thread_unsuspend(p);
796 PROC_SUNLOCK(p);
797 itimer_proc_continue(p);
798 kqtimer_proc_continue(p);
799 }
800
801 static int
proc_can_ptrace(struct thread * td,struct proc * p)802 proc_can_ptrace(struct thread *td, struct proc *p)
803 {
804 int error;
805
806 PROC_LOCK_ASSERT(p, MA_OWNED);
807
808 if ((p->p_flag & P_WEXIT) != 0)
809 return (ESRCH);
810
811 if ((error = p_cansee(td, p)) != 0)
812 return (error);
813 if ((error = p_candebug(td, p)) != 0)
814 return (error);
815
816 /* not being traced... */
817 if ((p->p_flag & P_TRACED) == 0)
818 return (EPERM);
819
820 /* not being traced by YOU */
821 if (p->p_pptr != td->td_proc)
822 return (EBUSY);
823
824 /* not currently stopped */
825 if ((p->p_flag & P_STOPPED_TRACE) == 0 ||
826 p->p_suspcount != p->p_numthreads ||
827 (p->p_flag & P_WAITED) == 0)
828 return (EBUSY);
829
830 return (0);
831 }
832
833 static struct thread *
ptrace_sel_coredump_thread(struct proc * p)834 ptrace_sel_coredump_thread(struct proc *p)
835 {
836 struct thread *td2;
837
838 PROC_LOCK_ASSERT(p, MA_OWNED);
839 MPASS((p->p_flag & P_STOPPED_TRACE) != 0);
840
841 FOREACH_THREAD_IN_PROC(p, td2) {
842 if ((td2->td_dbgflags & TDB_SSWITCH) != 0)
843 return (td2);
844 }
845 return (NULL);
846 }
847
848 int
kern_ptrace(struct thread * td,int req,pid_t pid,void * addr,int data)849 kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data)
850 {
851 struct iovec iov;
852 struct uio uio;
853 struct proc *curp, *p, *pp;
854 struct thread *td2 = NULL, *td3;
855 struct ptrace_io_desc *piod = NULL;
856 struct ptrace_lwpinfo *pl;
857 struct ptrace_sc_ret *psr;
858 struct ptrace_sc_remote *pscr;
859 struct file *fp;
860 struct ptrace_coredump *pc;
861 struct thr_coredump_req *tcq;
862 struct thr_syscall_req *tsr;
863 int error, num, tmp;
864 lwpid_t tid = 0, *buf;
865 #ifdef COMPAT_FREEBSD32
866 int wrap32 = 0, safe = 0;
867 #endif
868 bool proctree_locked, p2_req_set;
869
870 curp = td->td_proc;
871 proctree_locked = false;
872 p2_req_set = false;
873
874 /* Lock proctree before locking the process. */
875 switch (req) {
876 case PT_TRACE_ME:
877 case PT_ATTACH:
878 case PT_STEP:
879 case PT_CONTINUE:
880 case PT_TO_SCE:
881 case PT_TO_SCX:
882 case PT_SYSCALL:
883 case PT_FOLLOW_FORK:
884 case PT_LWP_EVENTS:
885 case PT_GET_EVENT_MASK:
886 case PT_SET_EVENT_MASK:
887 case PT_DETACH:
888 case PT_GET_SC_ARGS:
889 sx_xlock(&proctree_lock);
890 proctree_locked = true;
891 break;
892 default:
893 break;
894 }
895
896 if (req == PT_TRACE_ME) {
897 p = td->td_proc;
898 PROC_LOCK(p);
899 } else {
900 if (pid <= PID_MAX) {
901 if ((p = pfind(pid)) == NULL) {
902 if (proctree_locked)
903 sx_xunlock(&proctree_lock);
904 return (ESRCH);
905 }
906 } else {
907 td2 = tdfind(pid, -1);
908 if (td2 == NULL) {
909 if (proctree_locked)
910 sx_xunlock(&proctree_lock);
911 return (ESRCH);
912 }
913 p = td2->td_proc;
914 tid = pid;
915 pid = p->p_pid;
916 }
917 }
918 AUDIT_ARG_PROCESS(p);
919
920 if ((p->p_flag & P_WEXIT) != 0) {
921 error = ESRCH;
922 goto fail;
923 }
924 if ((error = p_cansee(td, p)) != 0)
925 goto fail;
926
927 if ((error = p_candebug(td, p)) != 0)
928 goto fail;
929
930 /*
931 * System processes can't be debugged.
932 */
933 if ((p->p_flag & P_SYSTEM) != 0) {
934 error = EINVAL;
935 goto fail;
936 }
937
938 if (tid == 0) {
939 if ((p->p_flag & P_STOPPED_TRACE) != 0)
940 td2 = p->p_xthread;
941 if (td2 == NULL)
942 td2 = FIRST_THREAD_IN_PROC(p);
943 tid = td2->td_tid;
944 }
945
946 #ifdef COMPAT_FREEBSD32
947 /*
948 * Test if we're a 32 bit client and what the target is.
949 * Set the wrap controls accordingly.
950 */
951 if (SV_CURPROC_FLAG(SV_ILP32)) {
952 if (SV_PROC_FLAG(td2->td_proc, SV_ILP32))
953 safe = 1;
954 wrap32 = 1;
955 }
956 #endif
957 /*
958 * Permissions check
959 */
960 switch (req) {
961 case PT_TRACE_ME:
962 /*
963 * Always legal, when there is a parent process which
964 * could trace us. Otherwise, reject.
965 */
966 if ((p->p_flag & P_TRACED) != 0) {
967 error = EBUSY;
968 goto fail;
969 }
970 if (p->p_pptr == initproc) {
971 error = EPERM;
972 goto fail;
973 }
974 break;
975
976 case PT_ATTACH:
977 /* Self */
978 if (p == td->td_proc) {
979 error = EINVAL;
980 goto fail;
981 }
982
983 /* Already traced */
984 if (p->p_flag & P_TRACED) {
985 error = EBUSY;
986 goto fail;
987 }
988
989 /* Can't trace an ancestor if you're being traced. */
990 if (curp->p_flag & P_TRACED) {
991 for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) {
992 if (pp == p) {
993 error = EINVAL;
994 goto fail;
995 }
996 }
997 }
998
999 /* OK */
1000 break;
1001
1002 case PT_CLEARSTEP:
1003 /* Allow thread to clear single step for itself */
1004 if (td->td_tid == tid)
1005 break;
1006
1007 /* FALLTHROUGH */
1008 default:
1009 /*
1010 * Check for ptrace eligibility before waiting for
1011 * holds to drain.
1012 */
1013 error = proc_can_ptrace(td, p);
1014 if (error != 0)
1015 goto fail;
1016
1017 /*
1018 * Block parallel ptrace requests. Most important, do
1019 * not allow other thread in debugger to continue the
1020 * debuggee until coredump finished.
1021 */
1022 while ((p->p_flag2 & P2_PTRACEREQ) != 0) {
1023 if (proctree_locked)
1024 sx_xunlock(&proctree_lock);
1025 error = msleep(&p->p_flag2, &p->p_mtx, PPAUSE | PCATCH |
1026 (proctree_locked ? PDROP : 0), "pptrace", 0);
1027 if (proctree_locked) {
1028 sx_xlock(&proctree_lock);
1029 PROC_LOCK(p);
1030 }
1031 if (error == 0 && td2->td_proc != p)
1032 error = ESRCH;
1033 if (error == 0)
1034 error = proc_can_ptrace(td, p);
1035 if (error != 0)
1036 goto fail;
1037 }
1038
1039 /* Ok */
1040 break;
1041 }
1042
1043 /*
1044 * Keep this process around and request parallel ptrace()
1045 * request to wait until we finish this request.
1046 */
1047 MPASS((p->p_flag2 & P2_PTRACEREQ) == 0);
1048 p->p_flag2 |= P2_PTRACEREQ;
1049 p2_req_set = true;
1050 _PHOLD(p);
1051
1052 /*
1053 * Actually do the requests
1054 */
1055
1056 td->td_retval[0] = 0;
1057
1058 switch (req) {
1059 case PT_TRACE_ME:
1060 /* set my trace flag and "owner" so it can read/write me */
1061 proc_set_traced(p, false);
1062 if (p->p_flag & P_PPWAIT)
1063 p->p_flag |= P_PPTRACE;
1064 CTR1(KTR_PTRACE, "PT_TRACE_ME: pid %d", p->p_pid);
1065 break;
1066
1067 case PT_ATTACH:
1068 /* security check done above */
1069 /*
1070 * It would be nice if the tracing relationship was separate
1071 * from the parent relationship but that would require
1072 * another set of links in the proc struct or for "wait"
1073 * to scan the entire proc table. To make life easier,
1074 * we just re-parent the process we're trying to trace.
1075 * The old parent is remembered so we can put things back
1076 * on a "detach".
1077 */
1078 proc_set_traced(p, true);
1079 proc_reparent(p, td->td_proc, false);
1080 CTR2(KTR_PTRACE, "PT_ATTACH: pid %d, oppid %d", p->p_pid,
1081 p->p_oppid);
1082
1083 sx_xunlock(&proctree_lock);
1084 proctree_locked = false;
1085 MPASS(p->p_xthread == NULL);
1086 MPASS((p->p_flag & P_STOPPED_TRACE) == 0);
1087
1088 /*
1089 * If already stopped due to a stop signal, clear the
1090 * existing stop before triggering a traced SIGSTOP.
1091 */
1092 if ((p->p_flag & P_STOPPED_SIG) != 0) {
1093 PROC_SLOCK(p);
1094 p->p_flag &= ~(P_STOPPED_SIG | P_WAITED);
1095 thread_unsuspend(p);
1096 PROC_SUNLOCK(p);
1097 }
1098
1099 kern_psignal(p, SIGSTOP);
1100 break;
1101
1102 case PT_CLEARSTEP:
1103 CTR2(KTR_PTRACE, "PT_CLEARSTEP: tid %d (pid %d)", td2->td_tid,
1104 p->p_pid);
1105 error = ptrace_clear_single_step(td2);
1106 break;
1107
1108 case PT_SETSTEP:
1109 CTR2(KTR_PTRACE, "PT_SETSTEP: tid %d (pid %d)", td2->td_tid,
1110 p->p_pid);
1111 error = ptrace_single_step(td2);
1112 break;
1113
1114 case PT_SUSPEND:
1115 CTR2(KTR_PTRACE, "PT_SUSPEND: tid %d (pid %d)", td2->td_tid,
1116 p->p_pid);
1117 td2->td_dbgflags |= TDB_SUSPEND;
1118 ast_sched(td2, TDA_SUSPEND);
1119 break;
1120
1121 case PT_RESUME:
1122 CTR2(KTR_PTRACE, "PT_RESUME: tid %d (pid %d)", td2->td_tid,
1123 p->p_pid);
1124 td2->td_dbgflags &= ~TDB_SUSPEND;
1125 break;
1126
1127 case PT_FOLLOW_FORK:
1128 CTR3(KTR_PTRACE, "PT_FOLLOW_FORK: pid %d %s -> %s", p->p_pid,
1129 p->p_ptevents & PTRACE_FORK ? "enabled" : "disabled",
1130 data ? "enabled" : "disabled");
1131 if (data)
1132 p->p_ptevents |= PTRACE_FORK;
1133 else
1134 p->p_ptevents &= ~PTRACE_FORK;
1135 break;
1136
1137 case PT_LWP_EVENTS:
1138 CTR3(KTR_PTRACE, "PT_LWP_EVENTS: pid %d %s -> %s", p->p_pid,
1139 p->p_ptevents & PTRACE_LWP ? "enabled" : "disabled",
1140 data ? "enabled" : "disabled");
1141 if (data)
1142 p->p_ptevents |= PTRACE_LWP;
1143 else
1144 p->p_ptevents &= ~PTRACE_LWP;
1145 break;
1146
1147 case PT_GET_EVENT_MASK:
1148 if (data != sizeof(p->p_ptevents)) {
1149 error = EINVAL;
1150 break;
1151 }
1152 CTR2(KTR_PTRACE, "PT_GET_EVENT_MASK: pid %d mask %#x", p->p_pid,
1153 p->p_ptevents);
1154 *(int *)addr = p->p_ptevents;
1155 break;
1156
1157 case PT_SET_EVENT_MASK:
1158 if (data != sizeof(p->p_ptevents)) {
1159 error = EINVAL;
1160 break;
1161 }
1162 tmp = *(int *)addr;
1163 if ((tmp & ~(PTRACE_EXEC | PTRACE_SCE | PTRACE_SCX |
1164 PTRACE_FORK | PTRACE_LWP | PTRACE_VFORK)) != 0) {
1165 error = EINVAL;
1166 break;
1167 }
1168 CTR3(KTR_PTRACE, "PT_SET_EVENT_MASK: pid %d mask %#x -> %#x",
1169 p->p_pid, p->p_ptevents, tmp);
1170 p->p_ptevents = tmp;
1171 break;
1172
1173 case PT_GET_SC_ARGS:
1174 CTR1(KTR_PTRACE, "PT_GET_SC_ARGS: pid %d", p->p_pid);
1175 if (((td2->td_dbgflags & (TDB_SCE | TDB_SCX)) == 0 &&
1176 td2->td_sa.code == 0)
1177 #ifdef COMPAT_FREEBSD32
1178 || (wrap32 && !safe)
1179 #endif
1180 ) {
1181 error = EINVAL;
1182 break;
1183 }
1184 bzero(addr, sizeof(td2->td_sa.args));
1185 /* See the explanation in linux_ptrace_get_syscall_info(). */
1186 bcopy(td2->td_sa.args, addr, SV_PROC_ABI(td->td_proc) ==
1187 SV_ABI_LINUX ? sizeof(td2->td_sa.args) :
1188 td2->td_sa.callp->sy_narg * sizeof(syscallarg_t));
1189 break;
1190
1191 case PT_GET_SC_RET:
1192 if ((td2->td_dbgflags & (TDB_SCX)) == 0
1193 #ifdef COMPAT_FREEBSD32
1194 || (wrap32 && !safe)
1195 #endif
1196 ) {
1197 error = EINVAL;
1198 break;
1199 }
1200 psr = addr;
1201 bzero(psr, sizeof(*psr));
1202 psr->sr_error = td2->td_errno;
1203 if (psr->sr_error == 0) {
1204 psr->sr_retval[0] = td2->td_retval[0];
1205 psr->sr_retval[1] = td2->td_retval[1];
1206 }
1207 CTR4(KTR_PTRACE,
1208 "PT_GET_SC_RET: pid %d error %d retval %#lx,%#lx",
1209 p->p_pid, psr->sr_error, psr->sr_retval[0],
1210 psr->sr_retval[1]);
1211 break;
1212
1213 case PT_STEP:
1214 case PT_CONTINUE:
1215 case PT_TO_SCE:
1216 case PT_TO_SCX:
1217 case PT_SYSCALL:
1218 case PT_DETACH:
1219 /* Zero means do not send any signal */
1220 if (data < 0 || data > _SIG_MAXSIG) {
1221 error = EINVAL;
1222 break;
1223 }
1224
1225 switch (req) {
1226 case PT_STEP:
1227 CTR3(KTR_PTRACE, "PT_STEP: tid %d (pid %d), sig = %d",
1228 td2->td_tid, p->p_pid, data);
1229 error = ptrace_single_step(td2);
1230 if (error)
1231 goto out;
1232 break;
1233 case PT_CONTINUE:
1234 case PT_TO_SCE:
1235 case PT_TO_SCX:
1236 case PT_SYSCALL:
1237 if (addr != (void *)1) {
1238 error = ptrace_set_pc(td2,
1239 (u_long)(uintfptr_t)addr);
1240 if (error)
1241 goto out;
1242 }
1243 switch (req) {
1244 case PT_TO_SCE:
1245 p->p_ptevents |= PTRACE_SCE;
1246 CTR4(KTR_PTRACE,
1247 "PT_TO_SCE: pid %d, events = %#x, PC = %#lx, sig = %d",
1248 p->p_pid, p->p_ptevents,
1249 (u_long)(uintfptr_t)addr, data);
1250 break;
1251 case PT_TO_SCX:
1252 p->p_ptevents |= PTRACE_SCX;
1253 CTR4(KTR_PTRACE,
1254 "PT_TO_SCX: pid %d, events = %#x, PC = %#lx, sig = %d",
1255 p->p_pid, p->p_ptevents,
1256 (u_long)(uintfptr_t)addr, data);
1257 break;
1258 case PT_SYSCALL:
1259 p->p_ptevents |= PTRACE_SYSCALL;
1260 CTR4(KTR_PTRACE,
1261 "PT_SYSCALL: pid %d, events = %#x, PC = %#lx, sig = %d",
1262 p->p_pid, p->p_ptevents,
1263 (u_long)(uintfptr_t)addr, data);
1264 break;
1265 case PT_CONTINUE:
1266 CTR3(KTR_PTRACE,
1267 "PT_CONTINUE: pid %d, PC = %#lx, sig = %d",
1268 p->p_pid, (u_long)(uintfptr_t)addr, data);
1269 break;
1270 }
1271 break;
1272 case PT_DETACH:
1273 /*
1274 * Clear P_TRACED before reparenting
1275 * a detached process back to its original
1276 * parent. Otherwise the debugee will be set
1277 * as an orphan of the debugger.
1278 */
1279 p->p_flag &= ~(P_TRACED | P_WAITED);
1280
1281 /*
1282 * Reset the process parent.
1283 */
1284 if (p->p_oppid != p->p_pptr->p_pid) {
1285 PROC_LOCK(p->p_pptr);
1286 sigqueue_take(p->p_ksi);
1287 PROC_UNLOCK(p->p_pptr);
1288
1289 pp = proc_realparent(p);
1290 proc_reparent(p, pp, false);
1291 if (pp == initproc)
1292 p->p_sigparent = SIGCHLD;
1293 CTR3(KTR_PTRACE,
1294 "PT_DETACH: pid %d reparented to pid %d, sig %d",
1295 p->p_pid, pp->p_pid, data);
1296 } else {
1297 CTR2(KTR_PTRACE, "PT_DETACH: pid %d, sig %d",
1298 p->p_pid, data);
1299 }
1300
1301 p->p_ptevents = 0;
1302 FOREACH_THREAD_IN_PROC(p, td3) {
1303 if ((td3->td_dbgflags & TDB_FSTP) != 0) {
1304 sigqueue_delete(&td3->td_sigqueue,
1305 SIGSTOP);
1306 }
1307 td3->td_dbgflags &= ~(TDB_XSIG | TDB_FSTP |
1308 TDB_SUSPEND | TDB_BORN);
1309 }
1310
1311 if ((p->p_flag2 & P2_PTRACE_FSTP) != 0) {
1312 sigqueue_delete(&p->p_sigqueue, SIGSTOP);
1313 p->p_flag2 &= ~P2_PTRACE_FSTP;
1314 }
1315
1316 /* should we send SIGCHLD? */
1317 /* childproc_continued(p); */
1318 break;
1319 }
1320
1321 sx_xunlock(&proctree_lock);
1322 proctree_locked = false;
1323
1324 sendsig:
1325 MPASS(!proctree_locked);
1326
1327 /*
1328 * Clear the pending event for the thread that just
1329 * reported its event (p_xthread), if any. This may
1330 * not be the thread passed to PT_CONTINUE, PT_STEP,
1331 * etc. if the debugger is resuming a different
1332 * thread. There might be no reporting thread if
1333 * the process was just attached.
1334 *
1335 * Deliver any pending signal via the reporting thread.
1336 */
1337 if (p->p_xthread != NULL) {
1338 p->p_xthread->td_dbgflags &= ~TDB_XSIG;
1339 p->p_xthread->td_xsig = data;
1340 p->p_xthread = NULL;
1341 }
1342 p->p_xsig = data;
1343
1344 /*
1345 * P_WKILLED is insurance that a PT_KILL/SIGKILL
1346 * always works immediately, even if another thread is
1347 * unsuspended first and attempts to handle a
1348 * different signal or if the POSIX.1b style signal
1349 * queue cannot accommodate any new signals.
1350 */
1351 if (data == SIGKILL)
1352 proc_wkilled(p);
1353
1354 /*
1355 * Unsuspend all threads. To leave a thread
1356 * suspended, use PT_SUSPEND to suspend it before
1357 * continuing the process.
1358 */
1359 ptrace_unsuspend(p);
1360 break;
1361
1362 case PT_WRITE_I:
1363 case PT_WRITE_D:
1364 td2->td_dbgflags |= TDB_USERWR;
1365 PROC_UNLOCK(p);
1366 error = 0;
1367 if (proc_writemem(td, p, (off_t)(uintptr_t)addr, &data,
1368 sizeof(int)) != sizeof(int))
1369 error = ENOMEM;
1370 else
1371 CTR3(KTR_PTRACE, "PT_WRITE: pid %d: %p <= %#x",
1372 p->p_pid, addr, data);
1373 PROC_LOCK(p);
1374 break;
1375
1376 case PT_READ_I:
1377 case PT_READ_D:
1378 PROC_UNLOCK(p);
1379 error = tmp = 0;
1380 if (proc_readmem(td, p, (off_t)(uintptr_t)addr, &tmp,
1381 sizeof(int)) != sizeof(int))
1382 error = ENOMEM;
1383 else
1384 CTR3(KTR_PTRACE, "PT_READ: pid %d: %p >= %#x",
1385 p->p_pid, addr, tmp);
1386 td->td_retval[0] = tmp;
1387 PROC_LOCK(p);
1388 break;
1389
1390 case PT_IO:
1391 piod = addr;
1392 if (piod->piod_len > SSIZE_MAX) {
1393 error = EINVAL;
1394 goto out;
1395 }
1396 iov.iov_base = piod->piod_addr;
1397 iov.iov_len = piod->piod_len;
1398 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs;
1399 uio.uio_resid = piod->piod_len;
1400 uio.uio_iov = &iov;
1401 uio.uio_iovcnt = 1;
1402 uio.uio_segflg = UIO_USERSPACE;
1403 uio.uio_td = td;
1404 switch (piod->piod_op) {
1405 case PIOD_READ_D:
1406 case PIOD_READ_I:
1407 CTR3(KTR_PTRACE, "PT_IO: pid %d: READ (%p, %#x)",
1408 p->p_pid, (uintptr_t)uio.uio_offset, uio.uio_resid);
1409 uio.uio_rw = UIO_READ;
1410 break;
1411 case PIOD_WRITE_D:
1412 case PIOD_WRITE_I:
1413 CTR3(KTR_PTRACE, "PT_IO: pid %d: WRITE (%p, %#x)",
1414 p->p_pid, (uintptr_t)uio.uio_offset, uio.uio_resid);
1415 td2->td_dbgflags |= TDB_USERWR;
1416 uio.uio_rw = UIO_WRITE;
1417 break;
1418 default:
1419 error = EINVAL;
1420 goto out;
1421 }
1422 PROC_UNLOCK(p);
1423 error = proc_rwmem(p, &uio);
1424 piod->piod_len -= uio.uio_resid;
1425 PROC_LOCK(p);
1426 break;
1427
1428 case PT_KILL:
1429 CTR1(KTR_PTRACE, "PT_KILL: pid %d", p->p_pid);
1430 data = SIGKILL;
1431 goto sendsig; /* in PT_CONTINUE above */
1432
1433 case PT_SETREGS:
1434 CTR2(KTR_PTRACE, "PT_SETREGS: tid %d (pid %d)", td2->td_tid,
1435 p->p_pid);
1436 td2->td_dbgflags |= TDB_USERWR;
1437 error = PROC_WRITE(regs, td2, addr);
1438 break;
1439
1440 case PT_GETREGS:
1441 CTR2(KTR_PTRACE, "PT_GETREGS: tid %d (pid %d)", td2->td_tid,
1442 p->p_pid);
1443 error = PROC_READ(regs, td2, addr);
1444 break;
1445
1446 case PT_SETFPREGS:
1447 CTR2(KTR_PTRACE, "PT_SETFPREGS: tid %d (pid %d)", td2->td_tid,
1448 p->p_pid);
1449 td2->td_dbgflags |= TDB_USERWR;
1450 error = PROC_WRITE(fpregs, td2, addr);
1451 break;
1452
1453 case PT_GETFPREGS:
1454 CTR2(KTR_PTRACE, "PT_GETFPREGS: tid %d (pid %d)", td2->td_tid,
1455 p->p_pid);
1456 error = PROC_READ(fpregs, td2, addr);
1457 break;
1458
1459 case PT_SETDBREGS:
1460 CTR2(KTR_PTRACE, "PT_SETDBREGS: tid %d (pid %d)", td2->td_tid,
1461 p->p_pid);
1462 td2->td_dbgflags |= TDB_USERWR;
1463 error = PROC_WRITE(dbregs, td2, addr);
1464 break;
1465
1466 case PT_GETDBREGS:
1467 CTR2(KTR_PTRACE, "PT_GETDBREGS: tid %d (pid %d)", td2->td_tid,
1468 p->p_pid);
1469 error = PROC_READ(dbregs, td2, addr);
1470 break;
1471
1472 case PT_SETREGSET:
1473 CTR2(KTR_PTRACE, "PT_SETREGSET: tid %d (pid %d)", td2->td_tid,
1474 p->p_pid);
1475 error = proc_write_regset(td2, data, addr);
1476 break;
1477
1478 case PT_GETREGSET:
1479 CTR2(KTR_PTRACE, "PT_GETREGSET: tid %d (pid %d)", td2->td_tid,
1480 p->p_pid);
1481 error = proc_read_regset(td2, data, addr);
1482 break;
1483
1484 case PT_LWPINFO:
1485 if (data <= 0 || data > sizeof(*pl)) {
1486 error = EINVAL;
1487 break;
1488 }
1489 pl = addr;
1490 bzero(pl, sizeof(*pl));
1491 pl->pl_lwpid = td2->td_tid;
1492 pl->pl_event = PL_EVENT_NONE;
1493 pl->pl_flags = 0;
1494 if (td2->td_dbgflags & TDB_XSIG) {
1495 pl->pl_event = PL_EVENT_SIGNAL;
1496 if (td2->td_si.si_signo != 0 &&
1497 data >= offsetof(struct ptrace_lwpinfo, pl_siginfo)
1498 + sizeof(pl->pl_siginfo)){
1499 pl->pl_flags |= PL_FLAG_SI;
1500 pl->pl_siginfo = td2->td_si;
1501 }
1502 }
1503 if (td2->td_dbgflags & TDB_SCE)
1504 pl->pl_flags |= PL_FLAG_SCE;
1505 else if (td2->td_dbgflags & TDB_SCX)
1506 pl->pl_flags |= PL_FLAG_SCX;
1507 if (td2->td_dbgflags & TDB_EXEC)
1508 pl->pl_flags |= PL_FLAG_EXEC;
1509 if (td2->td_dbgflags & TDB_FORK) {
1510 pl->pl_flags |= PL_FLAG_FORKED;
1511 pl->pl_child_pid = td2->td_dbg_forked;
1512 if (td2->td_dbgflags & TDB_VFORK)
1513 pl->pl_flags |= PL_FLAG_VFORKED;
1514 } else if ((td2->td_dbgflags & (TDB_SCX | TDB_VFORK)) ==
1515 TDB_VFORK)
1516 pl->pl_flags |= PL_FLAG_VFORK_DONE;
1517 if (td2->td_dbgflags & TDB_CHILD)
1518 pl->pl_flags |= PL_FLAG_CHILD;
1519 if (td2->td_dbgflags & TDB_BORN)
1520 pl->pl_flags |= PL_FLAG_BORN;
1521 if (td2->td_dbgflags & TDB_EXIT)
1522 pl->pl_flags |= PL_FLAG_EXITED;
1523 pl->pl_sigmask = td2->td_sigmask;
1524 pl->pl_siglist = td2->td_siglist;
1525 strcpy(pl->pl_tdname, td2->td_name);
1526 if (td2->td_sa.code != 0) {
1527 pl->pl_syscall_code = td2->td_sa.code;
1528 pl->pl_syscall_narg = td2->td_sa.callp->sy_narg;
1529 }
1530 CTR6(KTR_PTRACE,
1531 "PT_LWPINFO: tid %d (pid %d) event %d flags %#x child pid %d syscall %d",
1532 td2->td_tid, p->p_pid, pl->pl_event, pl->pl_flags,
1533 pl->pl_child_pid, pl->pl_syscall_code);
1534 break;
1535
1536 case PT_GETNUMLWPS:
1537 CTR2(KTR_PTRACE, "PT_GETNUMLWPS: pid %d: %d threads", p->p_pid,
1538 p->p_numthreads);
1539 td->td_retval[0] = p->p_numthreads;
1540 break;
1541
1542 case PT_GETLWPLIST:
1543 CTR3(KTR_PTRACE, "PT_GETLWPLIST: pid %d: data %d, actual %d",
1544 p->p_pid, data, p->p_numthreads);
1545 if (data <= 0) {
1546 error = EINVAL;
1547 break;
1548 }
1549 num = imin(p->p_numthreads, data);
1550 PROC_UNLOCK(p);
1551 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK);
1552 tmp = 0;
1553 PROC_LOCK(p);
1554 FOREACH_THREAD_IN_PROC(p, td2) {
1555 if (tmp >= num)
1556 break;
1557 buf[tmp++] = td2->td_tid;
1558 }
1559 PROC_UNLOCK(p);
1560 error = copyout(buf, addr, tmp * sizeof(lwpid_t));
1561 free(buf, M_TEMP);
1562 if (!error)
1563 td->td_retval[0] = tmp;
1564 PROC_LOCK(p);
1565 break;
1566
1567 case PT_VM_TIMESTAMP:
1568 CTR2(KTR_PTRACE, "PT_VM_TIMESTAMP: pid %d: timestamp %d",
1569 p->p_pid, p->p_vmspace->vm_map.timestamp);
1570 td->td_retval[0] = p->p_vmspace->vm_map.timestamp;
1571 break;
1572
1573 case PT_VM_ENTRY:
1574 PROC_UNLOCK(p);
1575 error = ptrace_vm_entry(td, p, addr);
1576 PROC_LOCK(p);
1577 break;
1578
1579 case PT_COREDUMP:
1580 pc = addr;
1581 CTR2(KTR_PTRACE, "PT_COREDUMP: pid %d, fd %d",
1582 p->p_pid, pc->pc_fd);
1583
1584 if ((pc->pc_flags & ~(PC_COMPRESS | PC_ALL)) != 0) {
1585 error = EINVAL;
1586 break;
1587 }
1588 PROC_UNLOCK(p);
1589
1590 tcq = malloc(sizeof(*tcq), M_TEMP, M_WAITOK | M_ZERO);
1591 fp = NULL;
1592 error = fget_write(td, pc->pc_fd, &cap_write_rights, &fp);
1593 if (error != 0)
1594 goto coredump_cleanup_nofp;
1595 if (fp->f_type != DTYPE_VNODE || fp->f_vnode->v_type != VREG) {
1596 error = EPIPE;
1597 goto coredump_cleanup;
1598 }
1599
1600 PROC_LOCK(p);
1601 error = proc_can_ptrace(td, p);
1602 if (error != 0)
1603 goto coredump_cleanup_locked;
1604
1605 td2 = ptrace_sel_coredump_thread(p);
1606 if (td2 == NULL) {
1607 error = EBUSY;
1608 goto coredump_cleanup_locked;
1609 }
1610 KASSERT((td2->td_dbgflags & (TDB_COREDUMPREQ |
1611 TDB_SCREMOTEREQ)) == 0,
1612 ("proc %d tid %d req coredump", p->p_pid, td2->td_tid));
1613
1614 tcq->tc_vp = fp->f_vnode;
1615 tcq->tc_limit = pc->pc_limit == 0 ? OFF_MAX : pc->pc_limit;
1616 tcq->tc_flags = SVC_PT_COREDUMP;
1617 if ((pc->pc_flags & PC_COMPRESS) == 0)
1618 tcq->tc_flags |= SVC_NOCOMPRESS;
1619 if ((pc->pc_flags & PC_ALL) != 0)
1620 tcq->tc_flags |= SVC_ALL;
1621 td2->td_remotereq = tcq;
1622 td2->td_dbgflags |= TDB_COREDUMPREQ;
1623 thread_run_flash(td2);
1624 while ((td2->td_dbgflags & TDB_COREDUMPREQ) != 0)
1625 msleep(p, &p->p_mtx, PPAUSE, "crdmp", 0);
1626 error = tcq->tc_error;
1627 coredump_cleanup_locked:
1628 PROC_UNLOCK(p);
1629 coredump_cleanup:
1630 fdrop(fp, td);
1631 coredump_cleanup_nofp:
1632 free(tcq, M_TEMP);
1633 PROC_LOCK(p);
1634 break;
1635
1636 case PT_SC_REMOTE:
1637 pscr = addr;
1638 CTR2(KTR_PTRACE, "PT_SC_REMOTE: pid %d, syscall %d",
1639 p->p_pid, pscr->pscr_syscall);
1640 if ((td2->td_dbgflags & TDB_BOUNDARY) == 0) {
1641 error = EBUSY;
1642 break;
1643 }
1644 PROC_UNLOCK(p);
1645 MPASS(pscr->pscr_nargs <= nitems(td->td_sa.args));
1646
1647 tsr = malloc(sizeof(struct thr_syscall_req), M_TEMP,
1648 M_WAITOK | M_ZERO);
1649
1650 tsr->ts_sa.code = pscr->pscr_syscall;
1651 tsr->ts_nargs = pscr->pscr_nargs;
1652 memcpy(&tsr->ts_sa.args, pscr->pscr_args,
1653 sizeof(syscallarg_t) * tsr->ts_nargs);
1654
1655 PROC_LOCK(p);
1656 error = proc_can_ptrace(td, p);
1657 if (error != 0) {
1658 free(tsr, M_TEMP);
1659 break;
1660 }
1661 if (td2->td_proc != p) {
1662 free(tsr, M_TEMP);
1663 error = ESRCH;
1664 break;
1665 }
1666 KASSERT((td2->td_dbgflags & (TDB_COREDUMPREQ |
1667 TDB_SCREMOTEREQ)) == 0,
1668 ("proc %d tid %d req coredump", p->p_pid, td2->td_tid));
1669
1670 td2->td_remotereq = tsr;
1671 td2->td_dbgflags |= TDB_SCREMOTEREQ;
1672 thread_run_flash(td2);
1673 while ((td2->td_dbgflags & TDB_SCREMOTEREQ) != 0)
1674 msleep(p, &p->p_mtx, PPAUSE, "pscrx", 0);
1675 error = 0;
1676 memcpy(&pscr->pscr_ret, &tsr->ts_ret, sizeof(tsr->ts_ret));
1677 free(tsr, M_TEMP);
1678 break;
1679
1680 default:
1681 #ifdef __HAVE_PTRACE_MACHDEP
1682 if (req >= PT_FIRSTMACH) {
1683 PROC_UNLOCK(p);
1684 error = cpu_ptrace(td2, req, addr, data);
1685 PROC_LOCK(p);
1686 } else
1687 #endif
1688 /* Unknown request. */
1689 error = EINVAL;
1690 break;
1691 }
1692 out:
1693 /* Drop our hold on this process now that the request has completed. */
1694 _PRELE(p);
1695 fail:
1696 if (p2_req_set) {
1697 if ((p->p_flag2 & P2_PTRACEREQ) != 0)
1698 wakeup(&p->p_flag2);
1699 p->p_flag2 &= ~P2_PTRACEREQ;
1700 }
1701 PROC_UNLOCK(p);
1702 if (proctree_locked)
1703 sx_xunlock(&proctree_lock);
1704 return (error);
1705 }
1706 #undef PROC_READ
1707 #undef PROC_WRITE
1708