73};
74
75struct ptrace_vm_entry32 {
76 int pve_entry;
77 int pve_timestamp;
78 uint32_t pve_start;
79 uint32_t pve_end;
80 uint32_t pve_offset;
81 u_int pve_prot;
82 u_int pve_pathlen;
83 int32_t pve_fileid;
84 u_int pve_fsid;
85 uint32_t pve_path;
86};
87
88#endif
89
90/*
91 * Functions implemented using PROC_ACTION():
92 *
93 * proc_read_regs(proc, regs)
94 * Get the current user-visible register set from the process
95 * and copy it into the regs structure (<machine/reg.h>).
96 * The process is stopped at the time read_regs is called.
97 *
98 * proc_write_regs(proc, regs)
99 * Update the current register set from the passed in regs
100 * structure. Take care to avoid clobbering special CPU
101 * registers or privileged bits in the PSL.
102 * Depending on the architecture this may have fix-up work to do,
103 * especially if the IAR or PCW are modified.
104 * The process is stopped at the time write_regs is called.
105 *
106 * proc_read_fpregs, proc_write_fpregs
107 * deal with the floating point register set, otherwise as above.
108 *
109 * proc_read_dbregs, proc_write_dbregs
110 * deal with the processor debug register set, otherwise as above.
111 *
112 * proc_sstep(proc)
113 * Arrange for the process to trap after executing a single instruction.
114 */
115
116#define PROC_ACTION(action) do { \
117 int error; \
118 \
119 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); \
120 if ((td->td_proc->p_flag & P_INMEM) == 0) \
121 error = EIO; \
122 else \
123 error = (action); \
124 return (error); \
125} while(0)
126
127int
128proc_read_regs(struct thread *td, struct reg *regs)
129{
130
131 PROC_ACTION(fill_regs(td, regs));
132}
133
134int
135proc_write_regs(struct thread *td, struct reg *regs)
136{
137
138 PROC_ACTION(set_regs(td, regs));
139}
140
141int
142proc_read_dbregs(struct thread *td, struct dbreg *dbregs)
143{
144
145 PROC_ACTION(fill_dbregs(td, dbregs));
146}
147
148int
149proc_write_dbregs(struct thread *td, struct dbreg *dbregs)
150{
151
152 PROC_ACTION(set_dbregs(td, dbregs));
153}
154
155/*
156 * Ptrace doesn't support fpregs at all, and there are no security holes
157 * or translations for fpregs, so we can just copy them.
158 */
159int
160proc_read_fpregs(struct thread *td, struct fpreg *fpregs)
161{
162
163 PROC_ACTION(fill_fpregs(td, fpregs));
164}
165
166int
167proc_write_fpregs(struct thread *td, struct fpreg *fpregs)
168{
169
170 PROC_ACTION(set_fpregs(td, fpregs));
171}
172
173#ifdef COMPAT_FREEBSD32
174/* For 32 bit binaries, we need to expose the 32 bit regs layouts. */
175int
176proc_read_regs32(struct thread *td, struct reg32 *regs32)
177{
178
179 PROC_ACTION(fill_regs32(td, regs32));
180}
181
182int
183proc_write_regs32(struct thread *td, struct reg32 *regs32)
184{
185
186 PROC_ACTION(set_regs32(td, regs32));
187}
188
189int
190proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
191{
192
193 PROC_ACTION(fill_dbregs32(td, dbregs32));
194}
195
196int
197proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
198{
199
200 PROC_ACTION(set_dbregs32(td, dbregs32));
201}
202
203int
204proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
205{
206
207 PROC_ACTION(fill_fpregs32(td, fpregs32));
208}
209
210int
211proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
212{
213
214 PROC_ACTION(set_fpregs32(td, fpregs32));
215}
216#endif
217
218int
219proc_sstep(struct thread *td)
220{
221
222 PROC_ACTION(ptrace_single_step(td));
223}
224
225int
226proc_rwmem(struct proc *p, struct uio *uio)
227{
228 vm_map_t map;
229 vm_object_t backing_object, object;
230 vm_offset_t pageno; /* page number */
231 vm_prot_t reqprot;
232 int error, writing;
233
234 /*
235 * Assert that someone has locked this vmspace. (Should be
236 * curthread but we can't assert that.) This keeps the process
237 * from exiting out from under us until this operation completes.
238 */
239 KASSERT(p->p_lock >= 1, ("%s: process %p (pid %d) not held", __func__,
240 p, p->p_pid));
241
242 /*
243 * The map we want...
244 */
245 map = &p->p_vmspace->vm_map;
246
247 writing = uio->uio_rw == UIO_WRITE;
248 reqprot = writing ? VM_PROT_COPY | VM_PROT_READ : VM_PROT_READ;
249
250 /*
251 * Only map in one page at a time. We don't have to, but it
252 * makes things easier. This way is trivial - right?
253 */
254 do {
255 vm_map_t tmap;
256 vm_offset_t uva;
257 int page_offset; /* offset into page */
258 vm_map_entry_t out_entry;
259 vm_prot_t out_prot;
260 boolean_t wired;
261 vm_pindex_t pindex;
262 u_int len;
263 vm_page_t m;
264
265 object = NULL;
266
267 uva = (vm_offset_t)uio->uio_offset;
268
269 /*
270 * Get the page number of this segment.
271 */
272 pageno = trunc_page(uva);
273 page_offset = uva - pageno;
274
275 /*
276 * How many bytes to copy
277 */
278 len = min(PAGE_SIZE - page_offset, uio->uio_resid);
279
280 /*
281 * Fault the page on behalf of the process
282 */
283 error = vm_fault(map, pageno, reqprot, VM_FAULT_NORMAL);
284 if (error) {
285 if (error == KERN_RESOURCE_SHORTAGE)
286 error = ENOMEM;
287 else
288 error = EFAULT;
289 break;
290 }
291
292 /*
293 * Now we need to get the page. out_entry and wired
294 * aren't used. One would think the vm code
295 * would be a *bit* nicer... We use tmap because
296 * vm_map_lookup() can change the map argument.
297 */
298 tmap = map;
299 error = vm_map_lookup(&tmap, pageno, reqprot, &out_entry,
300 &object, &pindex, &out_prot, &wired);
301 if (error) {
302 error = EFAULT;
303 break;
304 }
305 VM_OBJECT_LOCK(object);
306 while ((m = vm_page_lookup(object, pindex)) == NULL &&
307 !writing &&
308 (backing_object = object->backing_object) != NULL) {
309 /*
310 * Allow fallback to backing objects if we are reading.
311 */
312 VM_OBJECT_LOCK(backing_object);
313 pindex += OFF_TO_IDX(object->backing_object_offset);
314 VM_OBJECT_UNLOCK(object);
315 object = backing_object;
316 }
317 if (writing && m != NULL) {
318 vm_page_dirty(m);
319 vm_pager_page_unswapped(m);
320 }
321 VM_OBJECT_UNLOCK(object);
322 if (m == NULL) {
323 vm_map_lookup_done(tmap, out_entry);
324 error = EFAULT;
325 break;
326 }
327
328 /*
329 * Hold the page in memory.
330 */
331 vm_page_lock(m);
332 vm_page_hold(m);
333 vm_page_unlock(m);
334
335 /*
336 * We're done with tmap now.
337 */
338 vm_map_lookup_done(tmap, out_entry);
339
340 /*
341 * Now do the i/o move.
342 */
343 error = uiomove_fromphys(&m, page_offset, len, uio);
344
345 /* Make the I-cache coherent for breakpoints. */
346 if (!error && writing && (out_prot & VM_PROT_EXECUTE))
347 vm_sync_icache(map, uva, len);
348
349 /*
350 * Release the page.
351 */
352 vm_page_lock(m);
353 vm_page_unhold(m);
354 vm_page_unlock(m);
355
356 } while (error == 0 && uio->uio_resid > 0);
357
358 return (error);
359}
360
361static int
362ptrace_vm_entry(struct thread *td, struct proc *p, struct ptrace_vm_entry *pve)
363{
364 struct vattr vattr;
365 vm_map_t map;
366 vm_map_entry_t entry;
367 vm_object_t obj, tobj, lobj;
368 struct vmspace *vm;
369 struct vnode *vp;
370 char *freepath, *fullpath;
371 u_int pathlen;
372 int error, index, vfslocked;
373
374 error = 0;
375 obj = NULL;
376
377 vm = vmspace_acquire_ref(p);
378 map = &vm->vm_map;
379 vm_map_lock_read(map);
380
381 do {
382 entry = map->header.next;
383 index = 0;
384 while (index < pve->pve_entry && entry != &map->header) {
385 entry = entry->next;
386 index++;
387 }
388 if (index != pve->pve_entry) {
389 error = EINVAL;
390 break;
391 }
392 while (entry != &map->header &&
393 (entry->eflags & MAP_ENTRY_IS_SUB_MAP) != 0) {
394 entry = entry->next;
395 index++;
396 }
397 if (entry == &map->header) {
398 error = ENOENT;
399 break;
400 }
401
402 /* We got an entry. */
403 pve->pve_entry = index + 1;
404 pve->pve_timestamp = map->timestamp;
405 pve->pve_start = entry->start;
406 pve->pve_end = entry->end - 1;
407 pve->pve_offset = entry->offset;
408 pve->pve_prot = entry->protection;
409
410 /* Backing object's path needed? */
411 if (pve->pve_pathlen == 0)
412 break;
413
414 pathlen = pve->pve_pathlen;
415 pve->pve_pathlen = 0;
416
417 obj = entry->object.vm_object;
418 if (obj != NULL)
419 VM_OBJECT_LOCK(obj);
420 } while (0);
421
422 vm_map_unlock_read(map);
423 vmspace_free(vm);
424
425 pve->pve_fsid = VNOVAL;
426 pve->pve_fileid = VNOVAL;
427
428 if (error == 0 && obj != NULL) {
429 lobj = obj;
430 for (tobj = obj; tobj != NULL; tobj = tobj->backing_object) {
431 if (tobj != obj)
432 VM_OBJECT_LOCK(tobj);
433 if (lobj != obj)
434 VM_OBJECT_UNLOCK(lobj);
435 lobj = tobj;
436 pve->pve_offset += tobj->backing_object_offset;
437 }
438 vp = (lobj->type == OBJT_VNODE) ? lobj->handle : NULL;
439 if (vp != NULL)
440 vref(vp);
441 if (lobj != obj)
442 VM_OBJECT_UNLOCK(lobj);
443 VM_OBJECT_UNLOCK(obj);
444
445 if (vp != NULL) {
446 freepath = NULL;
447 fullpath = NULL;
448 vn_fullpath(td, vp, &fullpath, &freepath);
449 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
450 vn_lock(vp, LK_SHARED | LK_RETRY);
451 if (VOP_GETATTR(vp, &vattr, td->td_ucred) == 0) {
452 pve->pve_fileid = vattr.va_fileid;
453 pve->pve_fsid = vattr.va_fsid;
454 }
455 vput(vp);
456 VFS_UNLOCK_GIANT(vfslocked);
457
458 if (fullpath != NULL) {
459 pve->pve_pathlen = strlen(fullpath) + 1;
460 if (pve->pve_pathlen <= pathlen) {
461 error = copyout(fullpath, pve->pve_path,
462 pve->pve_pathlen);
463 } else
464 error = ENAMETOOLONG;
465 }
466 if (freepath != NULL)
467 free(freepath, M_TEMP);
468 }
469 }
470
471 return (error);
472}
473
474#ifdef COMPAT_FREEBSD32
475static int
476ptrace_vm_entry32(struct thread *td, struct proc *p,
477 struct ptrace_vm_entry32 *pve32)
478{
479 struct ptrace_vm_entry pve;
480 int error;
481
482 pve.pve_entry = pve32->pve_entry;
483 pve.pve_pathlen = pve32->pve_pathlen;
484 pve.pve_path = (void *)(uintptr_t)pve32->pve_path;
485
486 error = ptrace_vm_entry(td, p, &pve);
487 if (error == 0) {
488 pve32->pve_entry = pve.pve_entry;
489 pve32->pve_timestamp = pve.pve_timestamp;
490 pve32->pve_start = pve.pve_start;
491 pve32->pve_end = pve.pve_end;
492 pve32->pve_offset = pve.pve_offset;
493 pve32->pve_prot = pve.pve_prot;
494 pve32->pve_fileid = pve.pve_fileid;
495 pve32->pve_fsid = pve.pve_fsid;
496 }
497
498 pve32->pve_pathlen = pve.pve_pathlen;
499 return (error);
500}
501#endif /* COMPAT_FREEBSD32 */
502
503/*
504 * Process debugging system call.
505 */
506#ifndef _SYS_SYSPROTO_H_
507struct ptrace_args {
508 int req;
509 pid_t pid;
510 caddr_t addr;
511 int data;
512};
513#endif
514
515#ifdef COMPAT_FREEBSD32
516/*
517 * This CPP subterfuge is to try and reduce the number of ifdefs in
518 * the body of the code.
519 * COPYIN(uap->addr, &r.reg, sizeof r.reg);
520 * becomes either:
521 * copyin(uap->addr, &r.reg, sizeof r.reg);
522 * or
523 * copyin(uap->addr, &r.reg32, sizeof r.reg32);
524 * .. except this is done at runtime.
525 */
526#define COPYIN(u, k, s) wrap32 ? \
527 copyin(u, k ## 32, s ## 32) : \
528 copyin(u, k, s)
529#define COPYOUT(k, u, s) wrap32 ? \
530 copyout(k ## 32, u, s ## 32) : \
531 copyout(k, u, s)
532#else
533#define COPYIN(u, k, s) copyin(u, k, s)
534#define COPYOUT(k, u, s) copyout(k, u, s)
535#endif
536int
537ptrace(struct thread *td, struct ptrace_args *uap)
538{
539 /*
540 * XXX this obfuscation is to reduce stack usage, but the register
541 * structs may be too large to put on the stack anyway.
542 */
543 union {
544 struct ptrace_io_desc piod;
545 struct ptrace_lwpinfo pl;
546 struct ptrace_vm_entry pve;
547 struct dbreg dbreg;
548 struct fpreg fpreg;
549 struct reg reg;
550#ifdef COMPAT_FREEBSD32
551 struct dbreg32 dbreg32;
552 struct fpreg32 fpreg32;
553 struct reg32 reg32;
554 struct ptrace_io_desc32 piod32;
555 struct ptrace_vm_entry32 pve32;
556#endif
557 } r;
558 void *addr;
559 int error = 0;
560#ifdef COMPAT_FREEBSD32
561 int wrap32 = 0;
562
563 if (SV_CURPROC_FLAG(SV_ILP32))
564 wrap32 = 1;
565#endif
566 AUDIT_ARG_PID(uap->pid);
567 AUDIT_ARG_CMD(uap->req);
568 AUDIT_ARG_VALUE(uap->data);
569 addr = &r;
570 switch (uap->req) {
571 case PT_GETREGS:
572 case PT_GETFPREGS:
573 case PT_GETDBREGS:
574 case PT_LWPINFO:
575 break;
576 case PT_SETREGS:
577 error = COPYIN(uap->addr, &r.reg, sizeof r.reg);
578 break;
579 case PT_SETFPREGS:
580 error = COPYIN(uap->addr, &r.fpreg, sizeof r.fpreg);
581 break;
582 case PT_SETDBREGS:
583 error = COPYIN(uap->addr, &r.dbreg, sizeof r.dbreg);
584 break;
585 case PT_IO:
586 error = COPYIN(uap->addr, &r.piod, sizeof r.piod);
587 break;
588 case PT_VM_ENTRY:
589 error = COPYIN(uap->addr, &r.pve, sizeof r.pve);
590 break;
591 default:
592 addr = uap->addr;
593 break;
594 }
595 if (error)
596 return (error);
597
598 error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data);
599 if (error)
600 return (error);
601
602 switch (uap->req) {
603 case PT_VM_ENTRY:
604 error = COPYOUT(&r.pve, uap->addr, sizeof r.pve);
605 break;
606 case PT_IO:
607 error = COPYOUT(&r.piod, uap->addr, sizeof r.piod);
608 break;
609 case PT_GETREGS:
610 error = COPYOUT(&r.reg, uap->addr, sizeof r.reg);
611 break;
612 case PT_GETFPREGS:
613 error = COPYOUT(&r.fpreg, uap->addr, sizeof r.fpreg);
614 break;
615 case PT_GETDBREGS:
616 error = COPYOUT(&r.dbreg, uap->addr, sizeof r.dbreg);
617 break;
618 case PT_LWPINFO:
619 error = copyout(&r.pl, uap->addr, uap->data);
620 break;
621 }
622
623 return (error);
624}
625#undef COPYIN
626#undef COPYOUT
627
628#ifdef COMPAT_FREEBSD32
629/*
630 * PROC_READ(regs, td2, addr);
631 * becomes either:
632 * proc_read_regs(td2, addr);
633 * or
634 * proc_read_regs32(td2, addr);
635 * .. except this is done at runtime. There is an additional
636 * complication in that PROC_WRITE disallows 32 bit consumers
637 * from writing to 64 bit address space targets.
638 */
639#define PROC_READ(w, t, a) wrap32 ? \
640 proc_read_ ## w ## 32(t, a) : \
641 proc_read_ ## w (t, a)
642#define PROC_WRITE(w, t, a) wrap32 ? \
643 (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \
644 proc_write_ ## w (t, a)
645#else
646#define PROC_READ(w, t, a) proc_read_ ## w (t, a)
647#define PROC_WRITE(w, t, a) proc_write_ ## w (t, a)
648#endif
649
650int
651kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data)
652{
653 struct iovec iov;
654 struct uio uio;
655 struct proc *curp, *p, *pp;
656 struct thread *td2 = NULL;
657 struct ptrace_io_desc *piod = NULL;
658 struct ptrace_lwpinfo *pl;
659 int error, write, tmp, num;
660 int proctree_locked = 0;
661 lwpid_t tid = 0, *buf;
662#ifdef COMPAT_FREEBSD32
663 int wrap32 = 0, safe = 0;
664 struct ptrace_io_desc32 *piod32 = NULL;
665#endif
666
667 curp = td->td_proc;
668
669 /* Lock proctree before locking the process. */
670 switch (req) {
671 case PT_TRACE_ME:
672 case PT_ATTACH:
673 case PT_STEP:
674 case PT_CONTINUE:
675 case PT_TO_SCE:
676 case PT_TO_SCX:
677 case PT_SYSCALL:
678 case PT_DETACH:
679 sx_xlock(&proctree_lock);
680 proctree_locked = 1;
681 break;
682 default:
683 break;
684 }
685
686 write = 0;
687 if (req == PT_TRACE_ME) {
688 p = td->td_proc;
689 PROC_LOCK(p);
690 } else {
691 if (pid <= PID_MAX) {
692 if ((p = pfind(pid)) == NULL) {
693 if (proctree_locked)
694 sx_xunlock(&proctree_lock);
695 return (ESRCH);
696 }
697 } else {
698 /* this is slow, should be optimized */
699 sx_slock(&allproc_lock);
700 FOREACH_PROC_IN_SYSTEM(p) {
701 PROC_LOCK(p);
702 FOREACH_THREAD_IN_PROC(p, td2) {
703 if (td2->td_tid == pid)
704 break;
705 }
706 if (td2 != NULL)
707 break; /* proc lock held */
708 PROC_UNLOCK(p);
709 }
710 sx_sunlock(&allproc_lock);
711 if (p == NULL) {
712 if (proctree_locked)
713 sx_xunlock(&proctree_lock);
714 return (ESRCH);
715 }
716 tid = pid;
717 pid = p->p_pid;
718 }
719 }
720 AUDIT_ARG_PROCESS(p);
721
722 if ((p->p_flag & P_WEXIT) != 0) {
723 error = ESRCH;
724 goto fail;
725 }
726 if ((error = p_cansee(td, p)) != 0)
727 goto fail;
728
729 if ((error = p_candebug(td, p)) != 0)
730 goto fail;
731
732 /*
733 * System processes can't be debugged.
734 */
735 if ((p->p_flag & P_SYSTEM) != 0) {
736 error = EINVAL;
737 goto fail;
738 }
739
740 if (tid == 0) {
741 if ((p->p_flag & P_STOPPED_TRACE) != 0) {
742 KASSERT(p->p_xthread != NULL, ("NULL p_xthread"));
743 td2 = p->p_xthread;
744 } else {
745 td2 = FIRST_THREAD_IN_PROC(p);
746 }
747 tid = td2->td_tid;
748 }
749
750#ifdef COMPAT_FREEBSD32
751 /*
752 * Test if we're a 32 bit client and what the target is.
753 * Set the wrap controls accordingly.
754 */
755 if (SV_CURPROC_FLAG(SV_ILP32)) {
756 if (td2->td_proc->p_sysent->sv_flags & SV_ILP32)
757 safe = 1;
758 wrap32 = 1;
759 }
760#endif
761 /*
762 * Permissions check
763 */
764 switch (req) {
765 case PT_TRACE_ME:
766 /* Always legal. */
767 break;
768
769 case PT_ATTACH:
770 /* Self */
771 if (p->p_pid == td->td_proc->p_pid) {
772 error = EINVAL;
773 goto fail;
774 }
775
776 /* Already traced */
777 if (p->p_flag & P_TRACED) {
778 error = EBUSY;
779 goto fail;
780 }
781
782 /* Can't trace an ancestor if you're being traced. */
783 if (curp->p_flag & P_TRACED) {
784 for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) {
785 if (pp == p) {
786 error = EINVAL;
787 goto fail;
788 }
789 }
790 }
791
792
793 /* OK */
794 break;
795
796 case PT_CLEARSTEP:
797 /* Allow thread to clear single step for itself */
798 if (td->td_tid == tid)
799 break;
800
801 /* FALLTHROUGH */
802 default:
803 /* not being traced... */
804 if ((p->p_flag & P_TRACED) == 0) {
805 error = EPERM;
806 goto fail;
807 }
808
809 /* not being traced by YOU */
810 if (p->p_pptr != td->td_proc) {
811 error = EBUSY;
812 goto fail;
813 }
814
815 /* not currently stopped */
816 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) == 0 ||
817 p->p_suspcount != p->p_numthreads ||
818 (p->p_flag & P_WAITED) == 0) {
819 error = EBUSY;
820 goto fail;
821 }
822
823 if ((p->p_flag & P_STOPPED_TRACE) == 0) {
824 static int count = 0;
825 if (count++ == 0)
826 printf("P_STOPPED_TRACE not set.\n");
827 }
828
829 /* OK */
830 break;
831 }
832
833 /* Keep this process around until we finish this request. */
834 _PHOLD(p);
835
836#ifdef FIX_SSTEP
837 /*
838 * Single step fixup ala procfs
839 */
840 FIX_SSTEP(td2);
841#endif
842
843 /*
844 * Actually do the requests
845 */
846
847 td->td_retval[0] = 0;
848
849 switch (req) {
850 case PT_TRACE_ME:
851 /* set my trace flag and "owner" so it can read/write me */
852 p->p_flag |= P_TRACED;
853 p->p_oppid = p->p_pptr->p_pid;
854 break;
855
856 case PT_ATTACH:
857 /* security check done above */
858 p->p_flag |= P_TRACED;
859 p->p_oppid = p->p_pptr->p_pid;
860 if (p->p_pptr != td->td_proc)
861 proc_reparent(p, td->td_proc);
862 data = SIGSTOP;
863 goto sendsig; /* in PT_CONTINUE below */
864
865 case PT_CLEARSTEP:
866 error = ptrace_clear_single_step(td2);
867 break;
868
869 case PT_SETSTEP:
870 error = ptrace_single_step(td2);
871 break;
872
873 case PT_SUSPEND:
874 td2->td_dbgflags |= TDB_SUSPEND;
875 thread_lock(td2);
876 td2->td_flags |= TDF_NEEDSUSPCHK;
877 thread_unlock(td2);
878 break;
879
880 case PT_RESUME:
881 td2->td_dbgflags &= ~TDB_SUSPEND;
882 break;
883
884 case PT_STEP:
885 case PT_CONTINUE:
886 case PT_TO_SCE:
887 case PT_TO_SCX:
888 case PT_SYSCALL:
889 case PT_DETACH:
890 /* Zero means do not send any signal */
891 if (data < 0 || data > _SIG_MAXSIG) {
892 error = EINVAL;
893 break;
894 }
895
896 switch (req) {
897 case PT_STEP:
898 error = ptrace_single_step(td2);
899 if (error)
900 goto out;
901 break;
902 case PT_CONTINUE:
903 case PT_TO_SCE:
904 case PT_TO_SCX:
905 case PT_SYSCALL:
906 if (addr != (void *)1) {
907 error = ptrace_set_pc(td2,
908 (u_long)(uintfptr_t)addr);
909 if (error)
910 goto out;
911 }
912 switch (req) {
913 case PT_TO_SCE:
914 p->p_stops |= S_PT_SCE;
915 break;
916 case PT_TO_SCX:
917 p->p_stops |= S_PT_SCX;
918 break;
919 case PT_SYSCALL:
920 p->p_stops |= S_PT_SCE | S_PT_SCX;
921 break;
922 }
923 break;
924 case PT_DETACH:
925 /* reset process parent */
926 if (p->p_oppid != p->p_pptr->p_pid) {
927 struct proc *pp;
928
929 PROC_LOCK(p->p_pptr);
930 sigqueue_take(p->p_ksi);
931 PROC_UNLOCK(p->p_pptr);
932
933 PROC_UNLOCK(p);
934 pp = pfind(p->p_oppid);
935 if (pp == NULL)
936 pp = initproc;
937 else
938 PROC_UNLOCK(pp);
939 PROC_LOCK(p);
940 proc_reparent(p, pp);
941 if (pp == initproc)
942 p->p_sigparent = SIGCHLD;
943 }
944 p->p_flag &= ~(P_TRACED | P_WAITED);
945 p->p_oppid = 0;
946
947 /* should we send SIGCHLD? */
948 /* childproc_continued(p); */
949 break;
950 }
951
952 sendsig:
953 if (proctree_locked) {
954 sx_xunlock(&proctree_lock);
955 proctree_locked = 0;
956 }
957 p->p_xstat = data;
958 p->p_xthread = NULL;
959 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) != 0) {
960 /* deliver or queue signal */
961 td2->td_dbgflags &= ~TDB_XSIG;
962 td2->td_xsig = data;
963
964 if (req == PT_DETACH) {
965 struct thread *td3;
966 FOREACH_THREAD_IN_PROC(p, td3) {
967 td3->td_dbgflags &= ~TDB_SUSPEND;
968 }
969 }
970 /*
971 * unsuspend all threads, to not let a thread run,
972 * you should use PT_SUSPEND to suspend it before
973 * continuing process.
974 */
975 PROC_SLOCK(p);
976 p->p_flag &= ~(P_STOPPED_TRACE|P_STOPPED_SIG|P_WAITED);
977 thread_unsuspend(p);
978 PROC_SUNLOCK(p);
979 } else {
980 if (data)
981 psignal(p, data);
982 }
983 break;
984
985 case PT_WRITE_I:
986 case PT_WRITE_D:
987 td2->td_dbgflags |= TDB_USERWR;
988 write = 1;
989 /* FALLTHROUGH */
990 case PT_READ_I:
991 case PT_READ_D:
992 PROC_UNLOCK(p);
993 tmp = 0;
994 /* write = 0 set above */
995 iov.iov_base = write ? (caddr_t)&data : (caddr_t)&tmp;
996 iov.iov_len = sizeof(int);
997 uio.uio_iov = &iov;
998 uio.uio_iovcnt = 1;
999 uio.uio_offset = (off_t)(uintptr_t)addr;
1000 uio.uio_resid = sizeof(int);
1001 uio.uio_segflg = UIO_SYSSPACE; /* i.e.: the uap */
1002 uio.uio_rw = write ? UIO_WRITE : UIO_READ;
1003 uio.uio_td = td;
1004 error = proc_rwmem(p, &uio);
1005 if (uio.uio_resid != 0) {
1006 /*
1007 * XXX proc_rwmem() doesn't currently return ENOSPC,
1008 * so I think write() can bogusly return 0.
1009 * XXX what happens for short writes? We don't want
1010 * to write partial data.
1011 * XXX proc_rwmem() returns EPERM for other invalid
1012 * addresses. Convert this to EINVAL. Does this
1013 * clobber returns of EPERM for other reasons?
1014 */
1015 if (error == 0 || error == ENOSPC || error == EPERM)
1016 error = EINVAL; /* EOF */
1017 }
1018 if (!write)
1019 td->td_retval[0] = tmp;
1020 PROC_LOCK(p);
1021 break;
1022
1023 case PT_IO:
1024#ifdef COMPAT_FREEBSD32
1025 if (wrap32) {
1026 piod32 = addr;
1027 iov.iov_base = (void *)(uintptr_t)piod32->piod_addr;
1028 iov.iov_len = piod32->piod_len;
1029 uio.uio_offset = (off_t)(uintptr_t)piod32->piod_offs;
1030 uio.uio_resid = piod32->piod_len;
1031 } else
1032#endif
1033 {
1034 piod = addr;
1035 iov.iov_base = piod->piod_addr;
1036 iov.iov_len = piod->piod_len;
1037 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs;
1038 uio.uio_resid = piod->piod_len;
1039 }
1040 uio.uio_iov = &iov;
1041 uio.uio_iovcnt = 1;
1042 uio.uio_segflg = UIO_USERSPACE;
1043 uio.uio_td = td;
1044#ifdef COMPAT_FREEBSD32
1045 tmp = wrap32 ? piod32->piod_op : piod->piod_op;
1046#else
1047 tmp = piod->piod_op;
1048#endif
1049 switch (tmp) {
1050 case PIOD_READ_D:
1051 case PIOD_READ_I:
1052 uio.uio_rw = UIO_READ;
1053 break;
1054 case PIOD_WRITE_D:
1055 case PIOD_WRITE_I:
1056 td2->td_dbgflags |= TDB_USERWR;
1057 uio.uio_rw = UIO_WRITE;
1058 break;
1059 default:
1060 error = EINVAL;
1061 goto out;
1062 }
1063 PROC_UNLOCK(p);
1064 error = proc_rwmem(p, &uio);
1065#ifdef COMPAT_FREEBSD32
1066 if (wrap32)
1067 piod32->piod_len -= uio.uio_resid;
1068 else
1069#endif
1070 piod->piod_len -= uio.uio_resid;
1071 PROC_LOCK(p);
1072 break;
1073
1074 case PT_KILL:
1075 data = SIGKILL;
1076 goto sendsig; /* in PT_CONTINUE above */
1077
1078 case PT_SETREGS:
1079 td2->td_dbgflags |= TDB_USERWR;
1080 error = PROC_WRITE(regs, td2, addr);
1081 break;
1082
1083 case PT_GETREGS:
1084 error = PROC_READ(regs, td2, addr);
1085 break;
1086
1087 case PT_SETFPREGS:
1088 td2->td_dbgflags |= TDB_USERWR;
1089 error = PROC_WRITE(fpregs, td2, addr);
1090 break;
1091
1092 case PT_GETFPREGS:
1093 error = PROC_READ(fpregs, td2, addr);
1094 break;
1095
1096 case PT_SETDBREGS:
1097 td2->td_dbgflags |= TDB_USERWR;
1098 error = PROC_WRITE(dbregs, td2, addr);
1099 break;
1100
1101 case PT_GETDBREGS:
1102 error = PROC_READ(dbregs, td2, addr);
1103 break;
1104
1105 case PT_LWPINFO:
1106 if (data <= 0 || data > sizeof(*pl)) {
1107 error = EINVAL;
1108 break;
1109 }
1110 pl = addr;
1111 pl->pl_lwpid = td2->td_tid;
1112 if (td2->td_dbgflags & TDB_XSIG)
1113 pl->pl_event = PL_EVENT_SIGNAL;
1114 pl->pl_flags = 0;
1115 if (td2->td_dbgflags & TDB_SCE)
1116 pl->pl_flags |= PL_FLAG_SCE;
1117 else if (td2->td_dbgflags & TDB_SCX)
1118 pl->pl_flags |= PL_FLAG_SCX;
1119 if (td2->td_dbgflags & TDB_EXEC)
1120 pl->pl_flags |= PL_FLAG_EXEC;
1121 pl->pl_sigmask = td2->td_sigmask;
1122 pl->pl_siglist = td2->td_siglist;
1123 break;
1124
1125 case PT_GETNUMLWPS:
1126 td->td_retval[0] = p->p_numthreads;
1127 break;
1128
1129 case PT_GETLWPLIST:
1130 if (data <= 0) {
1131 error = EINVAL;
1132 break;
1133 }
1134 num = imin(p->p_numthreads, data);
1135 PROC_UNLOCK(p);
1136 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK);
1137 tmp = 0;
1138 PROC_LOCK(p);
1139 FOREACH_THREAD_IN_PROC(p, td2) {
1140 if (tmp >= num)
1141 break;
1142 buf[tmp++] = td2->td_tid;
1143 }
1144 PROC_UNLOCK(p);
1145 error = copyout(buf, addr, tmp * sizeof(lwpid_t));
1146 free(buf, M_TEMP);
1147 if (!error)
1148 td->td_retval[0] = tmp;
1149 PROC_LOCK(p);
1150 break;
1151
1152 case PT_VM_TIMESTAMP:
1153 td->td_retval[0] = p->p_vmspace->vm_map.timestamp;
1154 break;
1155
1156 case PT_VM_ENTRY:
1157 PROC_UNLOCK(p);
1158#ifdef COMPAT_FREEBSD32
1159 if (wrap32)
1160 error = ptrace_vm_entry32(td, p, addr);
1161 else
1162#endif
1163 error = ptrace_vm_entry(td, p, addr);
1164 PROC_LOCK(p);
1165 break;
1166
1167 default:
1168#ifdef __HAVE_PTRACE_MACHDEP
1169 if (req >= PT_FIRSTMACH) {
1170 PROC_UNLOCK(p);
1171 error = cpu_ptrace(td2, req, addr, data);
1172 PROC_LOCK(p);
1173 } else
1174#endif
1175 /* Unknown request. */
1176 error = EINVAL;
1177 break;
1178 }
1179
1180out:
1181 /* Drop our hold on this process now that the request has completed. */
1182 _PRELE(p);
1183fail:
1184 PROC_UNLOCK(p);
1185 if (proctree_locked)
1186 sx_xunlock(&proctree_lock);
1187 return (error);
1188}
1189#undef PROC_READ
1190#undef PROC_WRITE
1191
1192/*
1193 * Stop a process because of a debugging event;
1194 * stay stopped until p->p_step is cleared
1195 * (cleared by PIOCCONT in procfs).
1196 */
1197void
1198stopevent(struct proc *p, unsigned int event, unsigned int val)
1199{
1200
1201 PROC_LOCK_ASSERT(p, MA_OWNED);
1202 p->p_step = 1;
1203 do {
1204 p->p_xstat = val;
1205 p->p_xthread = NULL;
1206 p->p_stype = event; /* Which event caused the stop? */
1207 wakeup(&p->p_stype); /* Wake up any PIOCWAIT'ing procs */
1208 msleep(&p->p_step, &p->p_mtx, PWAIT, "stopevent", 0);
1209 } while (p->p_step);
1210}
| 73};
74
75struct ptrace_vm_entry32 {
76 int pve_entry;
77 int pve_timestamp;
78 uint32_t pve_start;
79 uint32_t pve_end;
80 uint32_t pve_offset;
81 u_int pve_prot;
82 u_int pve_pathlen;
83 int32_t pve_fileid;
84 u_int pve_fsid;
85 uint32_t pve_path;
86};
87
88#endif
89
90/*
91 * Functions implemented using PROC_ACTION():
92 *
93 * proc_read_regs(proc, regs)
94 * Get the current user-visible register set from the process
95 * and copy it into the regs structure (<machine/reg.h>).
96 * The process is stopped at the time read_regs is called.
97 *
98 * proc_write_regs(proc, regs)
99 * Update the current register set from the passed in regs
100 * structure. Take care to avoid clobbering special CPU
101 * registers or privileged bits in the PSL.
102 * Depending on the architecture this may have fix-up work to do,
103 * especially if the IAR or PCW are modified.
104 * The process is stopped at the time write_regs is called.
105 *
106 * proc_read_fpregs, proc_write_fpregs
107 * deal with the floating point register set, otherwise as above.
108 *
109 * proc_read_dbregs, proc_write_dbregs
110 * deal with the processor debug register set, otherwise as above.
111 *
112 * proc_sstep(proc)
113 * Arrange for the process to trap after executing a single instruction.
114 */
115
116#define PROC_ACTION(action) do { \
117 int error; \
118 \
119 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); \
120 if ((td->td_proc->p_flag & P_INMEM) == 0) \
121 error = EIO; \
122 else \
123 error = (action); \
124 return (error); \
125} while(0)
126
127int
128proc_read_regs(struct thread *td, struct reg *regs)
129{
130
131 PROC_ACTION(fill_regs(td, regs));
132}
133
134int
135proc_write_regs(struct thread *td, struct reg *regs)
136{
137
138 PROC_ACTION(set_regs(td, regs));
139}
140
141int
142proc_read_dbregs(struct thread *td, struct dbreg *dbregs)
143{
144
145 PROC_ACTION(fill_dbregs(td, dbregs));
146}
147
148int
149proc_write_dbregs(struct thread *td, struct dbreg *dbregs)
150{
151
152 PROC_ACTION(set_dbregs(td, dbregs));
153}
154
155/*
156 * Ptrace doesn't support fpregs at all, and there are no security holes
157 * or translations for fpregs, so we can just copy them.
158 */
159int
160proc_read_fpregs(struct thread *td, struct fpreg *fpregs)
161{
162
163 PROC_ACTION(fill_fpregs(td, fpregs));
164}
165
166int
167proc_write_fpregs(struct thread *td, struct fpreg *fpregs)
168{
169
170 PROC_ACTION(set_fpregs(td, fpregs));
171}
172
173#ifdef COMPAT_FREEBSD32
174/* For 32 bit binaries, we need to expose the 32 bit regs layouts. */
175int
176proc_read_regs32(struct thread *td, struct reg32 *regs32)
177{
178
179 PROC_ACTION(fill_regs32(td, regs32));
180}
181
182int
183proc_write_regs32(struct thread *td, struct reg32 *regs32)
184{
185
186 PROC_ACTION(set_regs32(td, regs32));
187}
188
189int
190proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
191{
192
193 PROC_ACTION(fill_dbregs32(td, dbregs32));
194}
195
196int
197proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
198{
199
200 PROC_ACTION(set_dbregs32(td, dbregs32));
201}
202
203int
204proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
205{
206
207 PROC_ACTION(fill_fpregs32(td, fpregs32));
208}
209
210int
211proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
212{
213
214 PROC_ACTION(set_fpregs32(td, fpregs32));
215}
216#endif
217
218int
219proc_sstep(struct thread *td)
220{
221
222 PROC_ACTION(ptrace_single_step(td));
223}
224
225int
226proc_rwmem(struct proc *p, struct uio *uio)
227{
228 vm_map_t map;
229 vm_object_t backing_object, object;
230 vm_offset_t pageno; /* page number */
231 vm_prot_t reqprot;
232 int error, writing;
233
234 /*
235 * Assert that someone has locked this vmspace. (Should be
236 * curthread but we can't assert that.) This keeps the process
237 * from exiting out from under us until this operation completes.
238 */
239 KASSERT(p->p_lock >= 1, ("%s: process %p (pid %d) not held", __func__,
240 p, p->p_pid));
241
242 /*
243 * The map we want...
244 */
245 map = &p->p_vmspace->vm_map;
246
247 writing = uio->uio_rw == UIO_WRITE;
248 reqprot = writing ? VM_PROT_COPY | VM_PROT_READ : VM_PROT_READ;
249
250 /*
251 * Only map in one page at a time. We don't have to, but it
252 * makes things easier. This way is trivial - right?
253 */
254 do {
255 vm_map_t tmap;
256 vm_offset_t uva;
257 int page_offset; /* offset into page */
258 vm_map_entry_t out_entry;
259 vm_prot_t out_prot;
260 boolean_t wired;
261 vm_pindex_t pindex;
262 u_int len;
263 vm_page_t m;
264
265 object = NULL;
266
267 uva = (vm_offset_t)uio->uio_offset;
268
269 /*
270 * Get the page number of this segment.
271 */
272 pageno = trunc_page(uva);
273 page_offset = uva - pageno;
274
275 /*
276 * How many bytes to copy
277 */
278 len = min(PAGE_SIZE - page_offset, uio->uio_resid);
279
280 /*
281 * Fault the page on behalf of the process
282 */
283 error = vm_fault(map, pageno, reqprot, VM_FAULT_NORMAL);
284 if (error) {
285 if (error == KERN_RESOURCE_SHORTAGE)
286 error = ENOMEM;
287 else
288 error = EFAULT;
289 break;
290 }
291
292 /*
293 * Now we need to get the page. out_entry and wired
294 * aren't used. One would think the vm code
295 * would be a *bit* nicer... We use tmap because
296 * vm_map_lookup() can change the map argument.
297 */
298 tmap = map;
299 error = vm_map_lookup(&tmap, pageno, reqprot, &out_entry,
300 &object, &pindex, &out_prot, &wired);
301 if (error) {
302 error = EFAULT;
303 break;
304 }
305 VM_OBJECT_LOCK(object);
306 while ((m = vm_page_lookup(object, pindex)) == NULL &&
307 !writing &&
308 (backing_object = object->backing_object) != NULL) {
309 /*
310 * Allow fallback to backing objects if we are reading.
311 */
312 VM_OBJECT_LOCK(backing_object);
313 pindex += OFF_TO_IDX(object->backing_object_offset);
314 VM_OBJECT_UNLOCK(object);
315 object = backing_object;
316 }
317 if (writing && m != NULL) {
318 vm_page_dirty(m);
319 vm_pager_page_unswapped(m);
320 }
321 VM_OBJECT_UNLOCK(object);
322 if (m == NULL) {
323 vm_map_lookup_done(tmap, out_entry);
324 error = EFAULT;
325 break;
326 }
327
328 /*
329 * Hold the page in memory.
330 */
331 vm_page_lock(m);
332 vm_page_hold(m);
333 vm_page_unlock(m);
334
335 /*
336 * We're done with tmap now.
337 */
338 vm_map_lookup_done(tmap, out_entry);
339
340 /*
341 * Now do the i/o move.
342 */
343 error = uiomove_fromphys(&m, page_offset, len, uio);
344
345 /* Make the I-cache coherent for breakpoints. */
346 if (!error && writing && (out_prot & VM_PROT_EXECUTE))
347 vm_sync_icache(map, uva, len);
348
349 /*
350 * Release the page.
351 */
352 vm_page_lock(m);
353 vm_page_unhold(m);
354 vm_page_unlock(m);
355
356 } while (error == 0 && uio->uio_resid > 0);
357
358 return (error);
359}
360
361static int
362ptrace_vm_entry(struct thread *td, struct proc *p, struct ptrace_vm_entry *pve)
363{
364 struct vattr vattr;
365 vm_map_t map;
366 vm_map_entry_t entry;
367 vm_object_t obj, tobj, lobj;
368 struct vmspace *vm;
369 struct vnode *vp;
370 char *freepath, *fullpath;
371 u_int pathlen;
372 int error, index, vfslocked;
373
374 error = 0;
375 obj = NULL;
376
377 vm = vmspace_acquire_ref(p);
378 map = &vm->vm_map;
379 vm_map_lock_read(map);
380
381 do {
382 entry = map->header.next;
383 index = 0;
384 while (index < pve->pve_entry && entry != &map->header) {
385 entry = entry->next;
386 index++;
387 }
388 if (index != pve->pve_entry) {
389 error = EINVAL;
390 break;
391 }
392 while (entry != &map->header &&
393 (entry->eflags & MAP_ENTRY_IS_SUB_MAP) != 0) {
394 entry = entry->next;
395 index++;
396 }
397 if (entry == &map->header) {
398 error = ENOENT;
399 break;
400 }
401
402 /* We got an entry. */
403 pve->pve_entry = index + 1;
404 pve->pve_timestamp = map->timestamp;
405 pve->pve_start = entry->start;
406 pve->pve_end = entry->end - 1;
407 pve->pve_offset = entry->offset;
408 pve->pve_prot = entry->protection;
409
410 /* Backing object's path needed? */
411 if (pve->pve_pathlen == 0)
412 break;
413
414 pathlen = pve->pve_pathlen;
415 pve->pve_pathlen = 0;
416
417 obj = entry->object.vm_object;
418 if (obj != NULL)
419 VM_OBJECT_LOCK(obj);
420 } while (0);
421
422 vm_map_unlock_read(map);
423 vmspace_free(vm);
424
425 pve->pve_fsid = VNOVAL;
426 pve->pve_fileid = VNOVAL;
427
428 if (error == 0 && obj != NULL) {
429 lobj = obj;
430 for (tobj = obj; tobj != NULL; tobj = tobj->backing_object) {
431 if (tobj != obj)
432 VM_OBJECT_LOCK(tobj);
433 if (lobj != obj)
434 VM_OBJECT_UNLOCK(lobj);
435 lobj = tobj;
436 pve->pve_offset += tobj->backing_object_offset;
437 }
438 vp = (lobj->type == OBJT_VNODE) ? lobj->handle : NULL;
439 if (vp != NULL)
440 vref(vp);
441 if (lobj != obj)
442 VM_OBJECT_UNLOCK(lobj);
443 VM_OBJECT_UNLOCK(obj);
444
445 if (vp != NULL) {
446 freepath = NULL;
447 fullpath = NULL;
448 vn_fullpath(td, vp, &fullpath, &freepath);
449 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
450 vn_lock(vp, LK_SHARED | LK_RETRY);
451 if (VOP_GETATTR(vp, &vattr, td->td_ucred) == 0) {
452 pve->pve_fileid = vattr.va_fileid;
453 pve->pve_fsid = vattr.va_fsid;
454 }
455 vput(vp);
456 VFS_UNLOCK_GIANT(vfslocked);
457
458 if (fullpath != NULL) {
459 pve->pve_pathlen = strlen(fullpath) + 1;
460 if (pve->pve_pathlen <= pathlen) {
461 error = copyout(fullpath, pve->pve_path,
462 pve->pve_pathlen);
463 } else
464 error = ENAMETOOLONG;
465 }
466 if (freepath != NULL)
467 free(freepath, M_TEMP);
468 }
469 }
470
471 return (error);
472}
473
474#ifdef COMPAT_FREEBSD32
475static int
476ptrace_vm_entry32(struct thread *td, struct proc *p,
477 struct ptrace_vm_entry32 *pve32)
478{
479 struct ptrace_vm_entry pve;
480 int error;
481
482 pve.pve_entry = pve32->pve_entry;
483 pve.pve_pathlen = pve32->pve_pathlen;
484 pve.pve_path = (void *)(uintptr_t)pve32->pve_path;
485
486 error = ptrace_vm_entry(td, p, &pve);
487 if (error == 0) {
488 pve32->pve_entry = pve.pve_entry;
489 pve32->pve_timestamp = pve.pve_timestamp;
490 pve32->pve_start = pve.pve_start;
491 pve32->pve_end = pve.pve_end;
492 pve32->pve_offset = pve.pve_offset;
493 pve32->pve_prot = pve.pve_prot;
494 pve32->pve_fileid = pve.pve_fileid;
495 pve32->pve_fsid = pve.pve_fsid;
496 }
497
498 pve32->pve_pathlen = pve.pve_pathlen;
499 return (error);
500}
501#endif /* COMPAT_FREEBSD32 */
502
503/*
504 * Process debugging system call.
505 */
506#ifndef _SYS_SYSPROTO_H_
507struct ptrace_args {
508 int req;
509 pid_t pid;
510 caddr_t addr;
511 int data;
512};
513#endif
514
515#ifdef COMPAT_FREEBSD32
516/*
517 * This CPP subterfuge is to try and reduce the number of ifdefs in
518 * the body of the code.
519 * COPYIN(uap->addr, &r.reg, sizeof r.reg);
520 * becomes either:
521 * copyin(uap->addr, &r.reg, sizeof r.reg);
522 * or
523 * copyin(uap->addr, &r.reg32, sizeof r.reg32);
524 * .. except this is done at runtime.
525 */
526#define COPYIN(u, k, s) wrap32 ? \
527 copyin(u, k ## 32, s ## 32) : \
528 copyin(u, k, s)
529#define COPYOUT(k, u, s) wrap32 ? \
530 copyout(k ## 32, u, s ## 32) : \
531 copyout(k, u, s)
532#else
533#define COPYIN(u, k, s) copyin(u, k, s)
534#define COPYOUT(k, u, s) copyout(k, u, s)
535#endif
536int
537ptrace(struct thread *td, struct ptrace_args *uap)
538{
539 /*
540 * XXX this obfuscation is to reduce stack usage, but the register
541 * structs may be too large to put on the stack anyway.
542 */
543 union {
544 struct ptrace_io_desc piod;
545 struct ptrace_lwpinfo pl;
546 struct ptrace_vm_entry pve;
547 struct dbreg dbreg;
548 struct fpreg fpreg;
549 struct reg reg;
550#ifdef COMPAT_FREEBSD32
551 struct dbreg32 dbreg32;
552 struct fpreg32 fpreg32;
553 struct reg32 reg32;
554 struct ptrace_io_desc32 piod32;
555 struct ptrace_vm_entry32 pve32;
556#endif
557 } r;
558 void *addr;
559 int error = 0;
560#ifdef COMPAT_FREEBSD32
561 int wrap32 = 0;
562
563 if (SV_CURPROC_FLAG(SV_ILP32))
564 wrap32 = 1;
565#endif
566 AUDIT_ARG_PID(uap->pid);
567 AUDIT_ARG_CMD(uap->req);
568 AUDIT_ARG_VALUE(uap->data);
569 addr = &r;
570 switch (uap->req) {
571 case PT_GETREGS:
572 case PT_GETFPREGS:
573 case PT_GETDBREGS:
574 case PT_LWPINFO:
575 break;
576 case PT_SETREGS:
577 error = COPYIN(uap->addr, &r.reg, sizeof r.reg);
578 break;
579 case PT_SETFPREGS:
580 error = COPYIN(uap->addr, &r.fpreg, sizeof r.fpreg);
581 break;
582 case PT_SETDBREGS:
583 error = COPYIN(uap->addr, &r.dbreg, sizeof r.dbreg);
584 break;
585 case PT_IO:
586 error = COPYIN(uap->addr, &r.piod, sizeof r.piod);
587 break;
588 case PT_VM_ENTRY:
589 error = COPYIN(uap->addr, &r.pve, sizeof r.pve);
590 break;
591 default:
592 addr = uap->addr;
593 break;
594 }
595 if (error)
596 return (error);
597
598 error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data);
599 if (error)
600 return (error);
601
602 switch (uap->req) {
603 case PT_VM_ENTRY:
604 error = COPYOUT(&r.pve, uap->addr, sizeof r.pve);
605 break;
606 case PT_IO:
607 error = COPYOUT(&r.piod, uap->addr, sizeof r.piod);
608 break;
609 case PT_GETREGS:
610 error = COPYOUT(&r.reg, uap->addr, sizeof r.reg);
611 break;
612 case PT_GETFPREGS:
613 error = COPYOUT(&r.fpreg, uap->addr, sizeof r.fpreg);
614 break;
615 case PT_GETDBREGS:
616 error = COPYOUT(&r.dbreg, uap->addr, sizeof r.dbreg);
617 break;
618 case PT_LWPINFO:
619 error = copyout(&r.pl, uap->addr, uap->data);
620 break;
621 }
622
623 return (error);
624}
625#undef COPYIN
626#undef COPYOUT
627
628#ifdef COMPAT_FREEBSD32
629/*
630 * PROC_READ(regs, td2, addr);
631 * becomes either:
632 * proc_read_regs(td2, addr);
633 * or
634 * proc_read_regs32(td2, addr);
635 * .. except this is done at runtime. There is an additional
636 * complication in that PROC_WRITE disallows 32 bit consumers
637 * from writing to 64 bit address space targets.
638 */
639#define PROC_READ(w, t, a) wrap32 ? \
640 proc_read_ ## w ## 32(t, a) : \
641 proc_read_ ## w (t, a)
642#define PROC_WRITE(w, t, a) wrap32 ? \
643 (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \
644 proc_write_ ## w (t, a)
645#else
646#define PROC_READ(w, t, a) proc_read_ ## w (t, a)
647#define PROC_WRITE(w, t, a) proc_write_ ## w (t, a)
648#endif
649
650int
651kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data)
652{
653 struct iovec iov;
654 struct uio uio;
655 struct proc *curp, *p, *pp;
656 struct thread *td2 = NULL;
657 struct ptrace_io_desc *piod = NULL;
658 struct ptrace_lwpinfo *pl;
659 int error, write, tmp, num;
660 int proctree_locked = 0;
661 lwpid_t tid = 0, *buf;
662#ifdef COMPAT_FREEBSD32
663 int wrap32 = 0, safe = 0;
664 struct ptrace_io_desc32 *piod32 = NULL;
665#endif
666
667 curp = td->td_proc;
668
669 /* Lock proctree before locking the process. */
670 switch (req) {
671 case PT_TRACE_ME:
672 case PT_ATTACH:
673 case PT_STEP:
674 case PT_CONTINUE:
675 case PT_TO_SCE:
676 case PT_TO_SCX:
677 case PT_SYSCALL:
678 case PT_DETACH:
679 sx_xlock(&proctree_lock);
680 proctree_locked = 1;
681 break;
682 default:
683 break;
684 }
685
686 write = 0;
687 if (req == PT_TRACE_ME) {
688 p = td->td_proc;
689 PROC_LOCK(p);
690 } else {
691 if (pid <= PID_MAX) {
692 if ((p = pfind(pid)) == NULL) {
693 if (proctree_locked)
694 sx_xunlock(&proctree_lock);
695 return (ESRCH);
696 }
697 } else {
698 /* this is slow, should be optimized */
699 sx_slock(&allproc_lock);
700 FOREACH_PROC_IN_SYSTEM(p) {
701 PROC_LOCK(p);
702 FOREACH_THREAD_IN_PROC(p, td2) {
703 if (td2->td_tid == pid)
704 break;
705 }
706 if (td2 != NULL)
707 break; /* proc lock held */
708 PROC_UNLOCK(p);
709 }
710 sx_sunlock(&allproc_lock);
711 if (p == NULL) {
712 if (proctree_locked)
713 sx_xunlock(&proctree_lock);
714 return (ESRCH);
715 }
716 tid = pid;
717 pid = p->p_pid;
718 }
719 }
720 AUDIT_ARG_PROCESS(p);
721
722 if ((p->p_flag & P_WEXIT) != 0) {
723 error = ESRCH;
724 goto fail;
725 }
726 if ((error = p_cansee(td, p)) != 0)
727 goto fail;
728
729 if ((error = p_candebug(td, p)) != 0)
730 goto fail;
731
732 /*
733 * System processes can't be debugged.
734 */
735 if ((p->p_flag & P_SYSTEM) != 0) {
736 error = EINVAL;
737 goto fail;
738 }
739
740 if (tid == 0) {
741 if ((p->p_flag & P_STOPPED_TRACE) != 0) {
742 KASSERT(p->p_xthread != NULL, ("NULL p_xthread"));
743 td2 = p->p_xthread;
744 } else {
745 td2 = FIRST_THREAD_IN_PROC(p);
746 }
747 tid = td2->td_tid;
748 }
749
750#ifdef COMPAT_FREEBSD32
751 /*
752 * Test if we're a 32 bit client and what the target is.
753 * Set the wrap controls accordingly.
754 */
755 if (SV_CURPROC_FLAG(SV_ILP32)) {
756 if (td2->td_proc->p_sysent->sv_flags & SV_ILP32)
757 safe = 1;
758 wrap32 = 1;
759 }
760#endif
761 /*
762 * Permissions check
763 */
764 switch (req) {
765 case PT_TRACE_ME:
766 /* Always legal. */
767 break;
768
769 case PT_ATTACH:
770 /* Self */
771 if (p->p_pid == td->td_proc->p_pid) {
772 error = EINVAL;
773 goto fail;
774 }
775
776 /* Already traced */
777 if (p->p_flag & P_TRACED) {
778 error = EBUSY;
779 goto fail;
780 }
781
782 /* Can't trace an ancestor if you're being traced. */
783 if (curp->p_flag & P_TRACED) {
784 for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) {
785 if (pp == p) {
786 error = EINVAL;
787 goto fail;
788 }
789 }
790 }
791
792
793 /* OK */
794 break;
795
796 case PT_CLEARSTEP:
797 /* Allow thread to clear single step for itself */
798 if (td->td_tid == tid)
799 break;
800
801 /* FALLTHROUGH */
802 default:
803 /* not being traced... */
804 if ((p->p_flag & P_TRACED) == 0) {
805 error = EPERM;
806 goto fail;
807 }
808
809 /* not being traced by YOU */
810 if (p->p_pptr != td->td_proc) {
811 error = EBUSY;
812 goto fail;
813 }
814
815 /* not currently stopped */
816 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) == 0 ||
817 p->p_suspcount != p->p_numthreads ||
818 (p->p_flag & P_WAITED) == 0) {
819 error = EBUSY;
820 goto fail;
821 }
822
823 if ((p->p_flag & P_STOPPED_TRACE) == 0) {
824 static int count = 0;
825 if (count++ == 0)
826 printf("P_STOPPED_TRACE not set.\n");
827 }
828
829 /* OK */
830 break;
831 }
832
833 /* Keep this process around until we finish this request. */
834 _PHOLD(p);
835
836#ifdef FIX_SSTEP
837 /*
838 * Single step fixup ala procfs
839 */
840 FIX_SSTEP(td2);
841#endif
842
843 /*
844 * Actually do the requests
845 */
846
847 td->td_retval[0] = 0;
848
849 switch (req) {
850 case PT_TRACE_ME:
851 /* set my trace flag and "owner" so it can read/write me */
852 p->p_flag |= P_TRACED;
853 p->p_oppid = p->p_pptr->p_pid;
854 break;
855
856 case PT_ATTACH:
857 /* security check done above */
858 p->p_flag |= P_TRACED;
859 p->p_oppid = p->p_pptr->p_pid;
860 if (p->p_pptr != td->td_proc)
861 proc_reparent(p, td->td_proc);
862 data = SIGSTOP;
863 goto sendsig; /* in PT_CONTINUE below */
864
865 case PT_CLEARSTEP:
866 error = ptrace_clear_single_step(td2);
867 break;
868
869 case PT_SETSTEP:
870 error = ptrace_single_step(td2);
871 break;
872
873 case PT_SUSPEND:
874 td2->td_dbgflags |= TDB_SUSPEND;
875 thread_lock(td2);
876 td2->td_flags |= TDF_NEEDSUSPCHK;
877 thread_unlock(td2);
878 break;
879
880 case PT_RESUME:
881 td2->td_dbgflags &= ~TDB_SUSPEND;
882 break;
883
884 case PT_STEP:
885 case PT_CONTINUE:
886 case PT_TO_SCE:
887 case PT_TO_SCX:
888 case PT_SYSCALL:
889 case PT_DETACH:
890 /* Zero means do not send any signal */
891 if (data < 0 || data > _SIG_MAXSIG) {
892 error = EINVAL;
893 break;
894 }
895
896 switch (req) {
897 case PT_STEP:
898 error = ptrace_single_step(td2);
899 if (error)
900 goto out;
901 break;
902 case PT_CONTINUE:
903 case PT_TO_SCE:
904 case PT_TO_SCX:
905 case PT_SYSCALL:
906 if (addr != (void *)1) {
907 error = ptrace_set_pc(td2,
908 (u_long)(uintfptr_t)addr);
909 if (error)
910 goto out;
911 }
912 switch (req) {
913 case PT_TO_SCE:
914 p->p_stops |= S_PT_SCE;
915 break;
916 case PT_TO_SCX:
917 p->p_stops |= S_PT_SCX;
918 break;
919 case PT_SYSCALL:
920 p->p_stops |= S_PT_SCE | S_PT_SCX;
921 break;
922 }
923 break;
924 case PT_DETACH:
925 /* reset process parent */
926 if (p->p_oppid != p->p_pptr->p_pid) {
927 struct proc *pp;
928
929 PROC_LOCK(p->p_pptr);
930 sigqueue_take(p->p_ksi);
931 PROC_UNLOCK(p->p_pptr);
932
933 PROC_UNLOCK(p);
934 pp = pfind(p->p_oppid);
935 if (pp == NULL)
936 pp = initproc;
937 else
938 PROC_UNLOCK(pp);
939 PROC_LOCK(p);
940 proc_reparent(p, pp);
941 if (pp == initproc)
942 p->p_sigparent = SIGCHLD;
943 }
944 p->p_flag &= ~(P_TRACED | P_WAITED);
945 p->p_oppid = 0;
946
947 /* should we send SIGCHLD? */
948 /* childproc_continued(p); */
949 break;
950 }
951
952 sendsig:
953 if (proctree_locked) {
954 sx_xunlock(&proctree_lock);
955 proctree_locked = 0;
956 }
957 p->p_xstat = data;
958 p->p_xthread = NULL;
959 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) != 0) {
960 /* deliver or queue signal */
961 td2->td_dbgflags &= ~TDB_XSIG;
962 td2->td_xsig = data;
963
964 if (req == PT_DETACH) {
965 struct thread *td3;
966 FOREACH_THREAD_IN_PROC(p, td3) {
967 td3->td_dbgflags &= ~TDB_SUSPEND;
968 }
969 }
970 /*
971 * unsuspend all threads, to not let a thread run,
972 * you should use PT_SUSPEND to suspend it before
973 * continuing process.
974 */
975 PROC_SLOCK(p);
976 p->p_flag &= ~(P_STOPPED_TRACE|P_STOPPED_SIG|P_WAITED);
977 thread_unsuspend(p);
978 PROC_SUNLOCK(p);
979 } else {
980 if (data)
981 psignal(p, data);
982 }
983 break;
984
985 case PT_WRITE_I:
986 case PT_WRITE_D:
987 td2->td_dbgflags |= TDB_USERWR;
988 write = 1;
989 /* FALLTHROUGH */
990 case PT_READ_I:
991 case PT_READ_D:
992 PROC_UNLOCK(p);
993 tmp = 0;
994 /* write = 0 set above */
995 iov.iov_base = write ? (caddr_t)&data : (caddr_t)&tmp;
996 iov.iov_len = sizeof(int);
997 uio.uio_iov = &iov;
998 uio.uio_iovcnt = 1;
999 uio.uio_offset = (off_t)(uintptr_t)addr;
1000 uio.uio_resid = sizeof(int);
1001 uio.uio_segflg = UIO_SYSSPACE; /* i.e.: the uap */
1002 uio.uio_rw = write ? UIO_WRITE : UIO_READ;
1003 uio.uio_td = td;
1004 error = proc_rwmem(p, &uio);
1005 if (uio.uio_resid != 0) {
1006 /*
1007 * XXX proc_rwmem() doesn't currently return ENOSPC,
1008 * so I think write() can bogusly return 0.
1009 * XXX what happens for short writes? We don't want
1010 * to write partial data.
1011 * XXX proc_rwmem() returns EPERM for other invalid
1012 * addresses. Convert this to EINVAL. Does this
1013 * clobber returns of EPERM for other reasons?
1014 */
1015 if (error == 0 || error == ENOSPC || error == EPERM)
1016 error = EINVAL; /* EOF */
1017 }
1018 if (!write)
1019 td->td_retval[0] = tmp;
1020 PROC_LOCK(p);
1021 break;
1022
1023 case PT_IO:
1024#ifdef COMPAT_FREEBSD32
1025 if (wrap32) {
1026 piod32 = addr;
1027 iov.iov_base = (void *)(uintptr_t)piod32->piod_addr;
1028 iov.iov_len = piod32->piod_len;
1029 uio.uio_offset = (off_t)(uintptr_t)piod32->piod_offs;
1030 uio.uio_resid = piod32->piod_len;
1031 } else
1032#endif
1033 {
1034 piod = addr;
1035 iov.iov_base = piod->piod_addr;
1036 iov.iov_len = piod->piod_len;
1037 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs;
1038 uio.uio_resid = piod->piod_len;
1039 }
1040 uio.uio_iov = &iov;
1041 uio.uio_iovcnt = 1;
1042 uio.uio_segflg = UIO_USERSPACE;
1043 uio.uio_td = td;
1044#ifdef COMPAT_FREEBSD32
1045 tmp = wrap32 ? piod32->piod_op : piod->piod_op;
1046#else
1047 tmp = piod->piod_op;
1048#endif
1049 switch (tmp) {
1050 case PIOD_READ_D:
1051 case PIOD_READ_I:
1052 uio.uio_rw = UIO_READ;
1053 break;
1054 case PIOD_WRITE_D:
1055 case PIOD_WRITE_I:
1056 td2->td_dbgflags |= TDB_USERWR;
1057 uio.uio_rw = UIO_WRITE;
1058 break;
1059 default:
1060 error = EINVAL;
1061 goto out;
1062 }
1063 PROC_UNLOCK(p);
1064 error = proc_rwmem(p, &uio);
1065#ifdef COMPAT_FREEBSD32
1066 if (wrap32)
1067 piod32->piod_len -= uio.uio_resid;
1068 else
1069#endif
1070 piod->piod_len -= uio.uio_resid;
1071 PROC_LOCK(p);
1072 break;
1073
1074 case PT_KILL:
1075 data = SIGKILL;
1076 goto sendsig; /* in PT_CONTINUE above */
1077
1078 case PT_SETREGS:
1079 td2->td_dbgflags |= TDB_USERWR;
1080 error = PROC_WRITE(regs, td2, addr);
1081 break;
1082
1083 case PT_GETREGS:
1084 error = PROC_READ(regs, td2, addr);
1085 break;
1086
1087 case PT_SETFPREGS:
1088 td2->td_dbgflags |= TDB_USERWR;
1089 error = PROC_WRITE(fpregs, td2, addr);
1090 break;
1091
1092 case PT_GETFPREGS:
1093 error = PROC_READ(fpregs, td2, addr);
1094 break;
1095
1096 case PT_SETDBREGS:
1097 td2->td_dbgflags |= TDB_USERWR;
1098 error = PROC_WRITE(dbregs, td2, addr);
1099 break;
1100
1101 case PT_GETDBREGS:
1102 error = PROC_READ(dbregs, td2, addr);
1103 break;
1104
1105 case PT_LWPINFO:
1106 if (data <= 0 || data > sizeof(*pl)) {
1107 error = EINVAL;
1108 break;
1109 }
1110 pl = addr;
1111 pl->pl_lwpid = td2->td_tid;
1112 if (td2->td_dbgflags & TDB_XSIG)
1113 pl->pl_event = PL_EVENT_SIGNAL;
1114 pl->pl_flags = 0;
1115 if (td2->td_dbgflags & TDB_SCE)
1116 pl->pl_flags |= PL_FLAG_SCE;
1117 else if (td2->td_dbgflags & TDB_SCX)
1118 pl->pl_flags |= PL_FLAG_SCX;
1119 if (td2->td_dbgflags & TDB_EXEC)
1120 pl->pl_flags |= PL_FLAG_EXEC;
1121 pl->pl_sigmask = td2->td_sigmask;
1122 pl->pl_siglist = td2->td_siglist;
1123 break;
1124
1125 case PT_GETNUMLWPS:
1126 td->td_retval[0] = p->p_numthreads;
1127 break;
1128
1129 case PT_GETLWPLIST:
1130 if (data <= 0) {
1131 error = EINVAL;
1132 break;
1133 }
1134 num = imin(p->p_numthreads, data);
1135 PROC_UNLOCK(p);
1136 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK);
1137 tmp = 0;
1138 PROC_LOCK(p);
1139 FOREACH_THREAD_IN_PROC(p, td2) {
1140 if (tmp >= num)
1141 break;
1142 buf[tmp++] = td2->td_tid;
1143 }
1144 PROC_UNLOCK(p);
1145 error = copyout(buf, addr, tmp * sizeof(lwpid_t));
1146 free(buf, M_TEMP);
1147 if (!error)
1148 td->td_retval[0] = tmp;
1149 PROC_LOCK(p);
1150 break;
1151
1152 case PT_VM_TIMESTAMP:
1153 td->td_retval[0] = p->p_vmspace->vm_map.timestamp;
1154 break;
1155
1156 case PT_VM_ENTRY:
1157 PROC_UNLOCK(p);
1158#ifdef COMPAT_FREEBSD32
1159 if (wrap32)
1160 error = ptrace_vm_entry32(td, p, addr);
1161 else
1162#endif
1163 error = ptrace_vm_entry(td, p, addr);
1164 PROC_LOCK(p);
1165 break;
1166
1167 default:
1168#ifdef __HAVE_PTRACE_MACHDEP
1169 if (req >= PT_FIRSTMACH) {
1170 PROC_UNLOCK(p);
1171 error = cpu_ptrace(td2, req, addr, data);
1172 PROC_LOCK(p);
1173 } else
1174#endif
1175 /* Unknown request. */
1176 error = EINVAL;
1177 break;
1178 }
1179
1180out:
1181 /* Drop our hold on this process now that the request has completed. */
1182 _PRELE(p);
1183fail:
1184 PROC_UNLOCK(p);
1185 if (proctree_locked)
1186 sx_xunlock(&proctree_lock);
1187 return (error);
1188}
1189#undef PROC_READ
1190#undef PROC_WRITE
1191
1192/*
1193 * Stop a process because of a debugging event;
1194 * stay stopped until p->p_step is cleared
1195 * (cleared by PIOCCONT in procfs).
1196 */
1197void
1198stopevent(struct proc *p, unsigned int event, unsigned int val)
1199{
1200
1201 PROC_LOCK_ASSERT(p, MA_OWNED);
1202 p->p_step = 1;
1203 do {
1204 p->p_xstat = val;
1205 p->p_xthread = NULL;
1206 p->p_stype = event; /* Which event caused the stop? */
1207 wakeup(&p->p_stype); /* Wake up any PIOCWAIT'ing procs */
1208 msleep(&p->p_step, &p->p_mtx, PWAIT, "stopevent", 0);
1209 } while (p->p_step);
1210}
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