sys_ptrace_common.c revision 1.2 1 /* $NetBSD: sys_ptrace_common.c,v 1.2 2016/11/04 18:14:04 christos Exp $ */
2
3 /*-
4 * Copyright (c) 2008, 2009 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Andrew Doran.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 /*-
33 * Copyright (c) 1982, 1986, 1989, 1993
34 * The Regents of the University of California. All rights reserved.
35 * (c) UNIX System Laboratories, Inc.
36 * All or some portions of this file are derived from material licensed
37 * to the University of California by American Telephone and Telegraph
38 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
39 * the permission of UNIX System Laboratories, Inc.
40 *
41 * This code is derived from software contributed to Berkeley by
42 * Jan-Simon Pendry.
43 *
44 * Redistribution and use in source and binary forms, with or without
45 * modification, are permitted provided that the following conditions
46 * are met:
47 * 1. Redistributions of source code must retain the above copyright
48 * notice, this list of conditions and the following disclaimer.
49 * 2. Redistributions in binary form must reproduce the above copyright
50 * notice, this list of conditions and the following disclaimer in the
51 * documentation and/or other materials provided with the distribution.
52 * 3. Neither the name of the University nor the names of its contributors
53 * may be used to endorse or promote products derived from this software
54 * without specific prior written permission.
55 *
56 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
57 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
58 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
59 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
60 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
61 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
62 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
63 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
64 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
65 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
66 * SUCH DAMAGE.
67 *
68 * from: @(#)sys_process.c 8.1 (Berkeley) 6/10/93
69 */
70
71 /*-
72 * Copyright (c) 1993 Jan-Simon Pendry.
73 * Copyright (c) 1994 Christopher G. Demetriou. All rights reserved.
74 *
75 * This code is derived from software contributed to Berkeley by
76 * Jan-Simon Pendry.
77 *
78 * Redistribution and use in source and binary forms, with or without
79 * modification, are permitted provided that the following conditions
80 * are met:
81 * 1. Redistributions of source code must retain the above copyright
82 * notice, this list of conditions and the following disclaimer.
83 * 2. Redistributions in binary form must reproduce the above copyright
84 * notice, this list of conditions and the following disclaimer in the
85 * documentation and/or other materials provided with the distribution.
86 * 3. All advertising materials mentioning features or use of this software
87 * must display the following acknowledgement:
88 * This product includes software developed by the University of
89 * California, Berkeley and its contributors.
90 * 4. Neither the name of the University nor the names of its contributors
91 * may be used to endorse or promote products derived from this software
92 * without specific prior written permission.
93 *
94 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
95 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
96 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
97 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
98 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
99 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
100 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
101 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
102 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
103 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
104 * SUCH DAMAGE.
105 *
106 * from: @(#)sys_process.c 8.1 (Berkeley) 6/10/93
107 */
108
109 /*
110 * References:
111 * (1) Bach's "The Design of the UNIX Operating System",
112 * (2) sys/miscfs/procfs from UCB's 4.4BSD-Lite distribution,
113 * (3) the "4.4BSD Programmer's Reference Manual" published
114 * by USENIX and O'Reilly & Associates.
115 * The 4.4BSD PRM does a reasonably good job of documenting what the various
116 * ptrace() requests should actually do, and its text is quoted several times
117 * in this file.
118 */
119
120 #include <sys/cdefs.h>
121 __KERNEL_RCSID(0, "$NetBSD: sys_ptrace_common.c,v 1.2 2016/11/04 18:14:04 christos Exp $");
122
123 #ifdef _KERNEL_OPT
124 #include "opt_ptrace.h"
125 #include "opt_ktrace.h"
126 #include "opt_pax.h"
127 #endif
128
129 #include <sys/param.h>
130 #include <sys/systm.h>
131 #include <sys/proc.h>
132 #include <sys/errno.h>
133 #include <sys/exec.h>
134 #include <sys/pax.h>
135 #include <sys/ptrace.h>
136 #include <sys/uio.h>
137 #include <sys/ras.h>
138 #include <sys/kmem.h>
139 #include <sys/kauth.h>
140 #include <sys/mount.h>
141 #include <sys/syscallargs.h>
142 #include <sys/module.h>
143 #include <sys/condvar.h>
144 #include <sys/mutex.h>
145
146 #include <uvm/uvm_extern.h>
147
148 #include <machine/reg.h>
149
150 #ifdef PTRACE
151
152 # ifdef DEBUG
153 # define DPRINTF(a) uprintf a
154 # else
155 # define DPRINTF(a)
156 # endif
157
158 static kauth_listener_t ptrace_listener;
159 static int process_auxv_offset(struct proc *, struct uio *);
160
161 #if 0
162 static int ptrace_cbref;
163 static kmutex_t ptrace_mtx;
164 static kcondvar_t ptrace_cv;
165 #endif
166
167 static int
168 ptrace_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie,
169 void *arg0, void *arg1, void *arg2, void *arg3)
170 {
171 struct proc *p;
172 int result;
173
174 result = KAUTH_RESULT_DEFER;
175 p = arg0;
176
177 #if 0
178 mutex_enter(&ptrace_mtx);
179 ptrace_cbref++;
180 mutex_exit(&ptrace_mtx);
181 #endif
182 if (action != KAUTH_PROCESS_PTRACE)
183 goto out;
184
185 switch ((u_long)arg1) {
186 case PT_TRACE_ME:
187 case PT_ATTACH:
188 case PT_WRITE_I:
189 case PT_WRITE_D:
190 case PT_READ_I:
191 case PT_READ_D:
192 case PT_IO:
193 #ifdef PT_GETREGS
194 case PT_GETREGS:
195 #endif
196 #ifdef PT_SETREGS
197 case PT_SETREGS:
198 #endif
199 #ifdef PT_GETFPREGS
200 case PT_GETFPREGS:
201 #endif
202 #ifdef PT_SETFPREGS
203 case PT_SETFPREGS:
204 #endif
205 case PT_SET_EVENT_MASK:
206 case PT_GET_EVENT_MASK:
207 case PT_GET_PROCESS_STATE:
208 #ifdef __HAVE_PTRACE_MACHDEP
209 PTRACE_MACHDEP_REQUEST_CASES
210 #endif
211 if (kauth_cred_getuid(cred) != kauth_cred_getuid(p->p_cred) ||
212 ISSET(p->p_flag, PK_SUGID)) {
213 break;
214 }
215
216 result = KAUTH_RESULT_ALLOW;
217
218 break;
219
220 #ifdef PT_STEP
221 case PT_STEP:
222 #endif
223 case PT_CONTINUE:
224 case PT_KILL:
225 case PT_DETACH:
226 case PT_LWPINFO:
227 case PT_SYSCALL:
228 case PT_SYSCALLEMU:
229 case PT_DUMPCORE:
230 result = KAUTH_RESULT_ALLOW;
231 break;
232
233 default:
234 break;
235 }
236
237 out:
238 #if 0
239 mutex_enter(&ptrace_mtx);
240 if (--ptrace_cbref == 0)
241 cv_broadcast(&ptrace_cv);
242 mutex_exit(&ptrace_mtx);
243 #endif
244
245 return result;
246 }
247
248 int
249 ptrace_init(void)
250 {
251
252 #if 0
253 mutex_init(&ptrace_mtx, MUTEX_DEFAULT, IPL_NONE);
254 cv_init(&ptrace_cv, "ptracecb");
255 ptrace_cbref = 0;
256 #endif
257 ptrace_listener = kauth_listen_scope(KAUTH_SCOPE_PROCESS,
258 ptrace_listener_cb, NULL);
259 return 0;
260 }
261
262 int
263 ptrace_fini(void)
264 {
265
266 kauth_unlisten_scope(ptrace_listener);
267
268 #if 0
269 /* Make sure no-one is executing our kauth listener */
270
271 mutex_enter(&ptrace_mtx);
272 while (ptrace_cbref != 0)
273 cv_wait(&ptrace_cv, &ptrace_mtx);
274 mutex_exit(&ptrace_mtx);
275 mutex_destroy(&ptrace_mtx);
276 cv_destroy(&ptrace_cv);
277 #endif
278
279 return 0;
280 }
281
282 int
283 do_ptrace(struct ptrace_methods *ptm, struct lwp *l, int req, pid_t pid,
284 void *addr, int data, register_t *retval)
285 {
286 struct proc *p = l->l_proc;
287 struct lwp *lt;
288 #ifdef PT_STEP
289 struct lwp *lt2;
290 #endif
291 struct proc *t; /* target process */
292 struct uio uio;
293 struct iovec iov;
294 struct ptrace_io_desc piod;
295 struct ptrace_event pe;
296 struct ptrace_state ps;
297 struct ptrace_lwpinfo pl;
298 struct vmspace *vm;
299 int error, write, tmp, pheld;
300 int signo = 0;
301 int resume_all;
302 ksiginfo_t ksi;
303 char *path;
304 int len = 0;
305 error = 0;
306
307 /*
308 * If attaching or detaching, we need to get a write hold on the
309 * proclist lock so that we can re-parent the target process.
310 */
311 mutex_enter(proc_lock);
312
313 /* "A foolish consistency..." XXX */
314 if (req == PT_TRACE_ME) {
315 t = p;
316 mutex_enter(t->p_lock);
317 } else {
318 /* Find the process we're supposed to be operating on. */
319 t = proc_find(pid);
320 if (t == NULL) {
321 mutex_exit(proc_lock);
322 return ESRCH;
323 }
324
325 /* XXX-elad */
326 mutex_enter(t->p_lock);
327 error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE,
328 t, KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENTRY), NULL, NULL);
329 if (error) {
330 mutex_exit(proc_lock);
331 mutex_exit(t->p_lock);
332 return ESRCH;
333 }
334 }
335
336 /*
337 * Grab a reference on the process to prevent it from execing or
338 * exiting.
339 */
340 if (!rw_tryenter(&t->p_reflock, RW_READER)) {
341 mutex_exit(proc_lock);
342 mutex_exit(t->p_lock);
343 return EBUSY;
344 }
345
346 /* Make sure we can operate on it. */
347 switch (req) {
348 case PT_TRACE_ME:
349 /* Saying that you're being traced is always legal. */
350 break;
351
352 case PT_ATTACH:
353 /*
354 * You can't attach to a process if:
355 * (1) it's the process that's doing the attaching,
356 */
357 if (t->p_pid == p->p_pid) {
358 error = EINVAL;
359 break;
360 }
361
362 /*
363 * (2) it's a system process
364 */
365 if (t->p_flag & PK_SYSTEM) {
366 error = EPERM;
367 break;
368 }
369
370 /*
371 * (3) it's already being traced, or
372 */
373 if (ISSET(t->p_slflag, PSL_TRACED)) {
374 error = EBUSY;
375 break;
376 }
377
378 /*
379 * (4) the tracer is chrooted, and its root directory is
380 * not at or above the root directory of the tracee
381 */
382 mutex_exit(t->p_lock); /* XXXSMP */
383 tmp = proc_isunder(t, l);
384 mutex_enter(t->p_lock); /* XXXSMP */
385 if (!tmp) {
386 error = EPERM;
387 break;
388 }
389 break;
390
391 case PT_READ_I:
392 case PT_READ_D:
393 case PT_WRITE_I:
394 case PT_WRITE_D:
395 case PT_IO:
396 #ifdef PT_GETREGS
397 case PT_GETREGS:
398 #endif
399 #ifdef PT_SETREGS
400 case PT_SETREGS:
401 #endif
402 #ifdef PT_GETFPREGS
403 case PT_GETFPREGS:
404 #endif
405 #ifdef PT_SETFPREGS
406 case PT_SETFPREGS:
407 #endif
408 #ifdef __HAVE_PTRACE_MACHDEP
409 PTRACE_MACHDEP_REQUEST_CASES
410 #endif
411 /*
412 * You can't read/write the memory or registers of a process
413 * if the tracer is chrooted, and its root directory is not at
414 * or above the root directory of the tracee.
415 */
416 mutex_exit(t->p_lock); /* XXXSMP */
417 tmp = proc_isunder(t, l);
418 mutex_enter(t->p_lock); /* XXXSMP */
419 if (!tmp) {
420 error = EPERM;
421 break;
422 }
423 /*FALLTHROUGH*/
424
425 case PT_CONTINUE:
426 case PT_KILL:
427 case PT_DETACH:
428 case PT_LWPINFO:
429 case PT_SYSCALL:
430 case PT_SYSCALLEMU:
431 case PT_DUMPCORE:
432 #ifdef PT_STEP
433 case PT_STEP:
434 #endif
435 case PT_SET_EVENT_MASK:
436 case PT_GET_EVENT_MASK:
437 case PT_GET_PROCESS_STATE:
438 /*
439 * You can't do what you want to the process if:
440 * (1) It's not being traced at all,
441 */
442 if (!ISSET(t->p_slflag, PSL_TRACED)) {
443 error = EPERM;
444 break;
445 }
446
447 /*
448 * (2) it's being traced by procfs (which has
449 * different signal delivery semantics),
450 */
451 if (ISSET(t->p_slflag, PSL_FSTRACE)) {
452 DPRINTF(("file system traced\n"));
453 error = EBUSY;
454 break;
455 }
456
457 /*
458 * (3) it's not being traced by _you_, or
459 */
460 if (t->p_pptr != p) {
461 DPRINTF(("parent %d != %d\n", t->p_pptr->p_pid,
462 p->p_pid));
463 error = EBUSY;
464 break;
465 }
466
467 /*
468 * (4) it's not currently stopped.
469 */
470 if (t->p_stat != SSTOP || !t->p_waited /* XXXSMP */) {
471 DPRINTF(("stat %d flag %d\n", t->p_stat,
472 !t->p_waited));
473 error = EBUSY;
474 break;
475 }
476 break;
477
478 default: /* It was not a legal request. */
479 error = EINVAL;
480 break;
481 }
482
483 if (error == 0) {
484 error = kauth_authorize_process(l->l_cred,
485 KAUTH_PROCESS_PTRACE, t, KAUTH_ARG(req),
486 NULL, NULL);
487 }
488 if (error == 0) {
489 lt = lwp_find_first(t);
490 if (lt == NULL)
491 error = ESRCH;
492 }
493
494 if (error != 0) {
495 mutex_exit(proc_lock);
496 mutex_exit(t->p_lock);
497 rw_exit(&t->p_reflock);
498 return error;
499 }
500
501 /* Do single-step fixup if needed. */
502 FIX_SSTEP(t);
503 KASSERT(lt != NULL);
504 lwp_addref(lt);
505
506 /*
507 * Which locks do we need held? XXX Ugly.
508 */
509 switch (req) {
510 #ifdef PT_STEP
511 case PT_STEP:
512 #endif
513 case PT_CONTINUE:
514 case PT_DETACH:
515 case PT_KILL:
516 case PT_SYSCALL:
517 case PT_SYSCALLEMU:
518 case PT_ATTACH:
519 case PT_TRACE_ME:
520 pheld = 1;
521 break;
522 default:
523 mutex_exit(proc_lock);
524 mutex_exit(t->p_lock);
525 pheld = 0;
526 break;
527 }
528
529 /* Now do the operation. */
530 write = 0;
531 *retval = 0;
532 tmp = 0;
533 resume_all = 1;
534
535 switch (req) {
536 case PT_TRACE_ME:
537 /* Just set the trace flag. */
538 SET(t->p_slflag, PSL_TRACED);
539 t->p_opptr = t->p_pptr;
540 break;
541
542 case PT_WRITE_I: /* XXX no separate I and D spaces */
543 case PT_WRITE_D:
544 #if defined(__HAVE_RAS)
545 /*
546 * Can't write to a RAS
547 */
548 if (ras_lookup(t, addr) != (void *)-1) {
549 error = EACCES;
550 break;
551 }
552 #endif
553 write = 1;
554 tmp = data;
555 /* FALLTHROUGH */
556
557 case PT_READ_I: /* XXX no separate I and D spaces */
558 case PT_READ_D:
559 /* write = 0 done above. */
560 iov.iov_base = (void *)&tmp;
561 iov.iov_len = sizeof(tmp);
562 uio.uio_iov = &iov;
563 uio.uio_iovcnt = 1;
564 uio.uio_offset = (off_t)(unsigned long)addr;
565 uio.uio_resid = sizeof(tmp);
566 uio.uio_rw = write ? UIO_WRITE : UIO_READ;
567 UIO_SETUP_SYSSPACE(&uio);
568
569 error = process_domem(l, lt, &uio);
570 if (!write)
571 *retval = tmp;
572 break;
573
574 case PT_IO:
575 error = ptm->ptm_copyinpiod(&piod, addr);
576 if (error)
577 break;
578
579 iov.iov_base = piod.piod_addr;
580 iov.iov_len = piod.piod_len;
581 uio.uio_iov = &iov;
582 uio.uio_iovcnt = 1;
583 uio.uio_offset = (off_t)(unsigned long)piod.piod_offs;
584 uio.uio_resid = piod.piod_len;
585
586 switch (piod.piod_op) {
587 case PIOD_READ_D:
588 case PIOD_READ_I:
589 uio.uio_rw = UIO_READ;
590 break;
591 case PIOD_WRITE_D:
592 case PIOD_WRITE_I:
593 /*
594 * Can't write to a RAS
595 */
596 if (ras_lookup(t, addr) != (void *)-1) {
597 return EACCES;
598 }
599 uio.uio_rw = UIO_WRITE;
600 break;
601 case PIOD_READ_AUXV:
602 req = PT_READ_D;
603 uio.uio_rw = UIO_READ;
604 tmp = t->p_execsw->es_arglen * PROC_PTRSZ(t);
605 if (uio.uio_offset > tmp)
606 return EIO;
607 if (uio.uio_resid > tmp - uio.uio_offset)
608 uio.uio_resid = tmp - uio.uio_offset;
609 piod.piod_len = iov.iov_len = uio.uio_resid;
610 error = process_auxv_offset(t, &uio);
611 if (error)
612 return error;
613 break;
614 default:
615 error = EINVAL;
616 break;
617 }
618 if (error)
619 break;
620 error = proc_vmspace_getref(l->l_proc, &vm);
621 if (error)
622 break;
623 uio.uio_vmspace = vm;
624
625 error = process_domem(l, lt, &uio);
626 piod.piod_len -= uio.uio_resid;
627 (void) ptm->ptm_copyoutpiod(&piod, addr);
628
629 uvmspace_free(vm);
630 break;
631
632 case PT_DUMPCORE:
633 if ((path = addr) != NULL) {
634 char *dst;
635 len = data;
636
637 if (len < 0 || len >= MAXPATHLEN) {
638 error = EINVAL;
639 break;
640 }
641 dst = kmem_alloc(len + 1, KM_SLEEP);
642 if ((error = copyin(path, dst, len)) != 0) {
643 kmem_free(dst, len + 1);
644 break;
645 }
646 path = dst;
647 path[len] = '\0';
648 }
649 error = (*coredump_vec)(lt, path);
650 if (path)
651 kmem_free(path, len + 1);
652 break;
653
654 #ifdef PT_STEP
655 case PT_STEP:
656 /*
657 * From the 4.4BSD PRM:
658 * "Execution continues as in request PT_CONTINUE; however
659 * as soon as possible after execution of at least one
660 * instruction, execution stops again. [ ... ]"
661 */
662 #endif
663 case PT_CONTINUE:
664 case PT_SYSCALL:
665 case PT_DETACH:
666 if (req == PT_SYSCALL) {
667 if (!ISSET(t->p_slflag, PSL_SYSCALL)) {
668 SET(t->p_slflag, PSL_SYSCALL);
669 #ifdef __HAVE_SYSCALL_INTERN
670 (*t->p_emul->e_syscall_intern)(t);
671 #endif
672 }
673 } else {
674 if (ISSET(t->p_slflag, PSL_SYSCALL)) {
675 CLR(t->p_slflag, PSL_SYSCALL);
676 #ifdef __HAVE_SYSCALL_INTERN
677 (*t->p_emul->e_syscall_intern)(t);
678 #endif
679 }
680 }
681 t->p_trace_enabled = trace_is_enabled(t);
682
683 /*
684 * Pick up the LWPID, if supplied. There are two cases:
685 * data < 0 : step or continue single thread, lwp = -data
686 * data > 0 in PT_STEP : step this thread, continue others
687 * For operations other than PT_STEP, data > 0 means
688 * data is the signo to deliver to the process.
689 */
690 tmp = data;
691 if (tmp >= 0) {
692 #ifdef PT_STEP
693 if (req == PT_STEP)
694 signo = 0;
695 else
696 #endif
697 {
698 signo = tmp;
699 tmp = 0; /* don't search for LWP */
700 }
701 } else
702 tmp = -tmp;
703
704 if (tmp > 0) {
705 if (req == PT_DETACH) {
706 error = EINVAL;
707 break;
708 }
709 lwp_delref2 (lt);
710 lt = lwp_find(t, tmp);
711 if (lt == NULL) {
712 error = ESRCH;
713 break;
714 }
715 lwp_addref(lt);
716 resume_all = 0;
717 signo = 0;
718 }
719
720 /*
721 * From the 4.4BSD PRM:
722 * "The data argument is taken as a signal number and the
723 * child's execution continues at location addr as if it
724 * incurred that signal. Normally the signal number will
725 * be either 0 to indicate that the signal that caused the
726 * stop should be ignored, or that value fetched out of
727 * the process's image indicating which signal caused
728 * the stop. If addr is (int *)1 then execution continues
729 * from where it stopped."
730 */
731
732 /* Check that the data is a valid signal number or zero. */
733 if (signo < 0 || signo >= NSIG) {
734 error = EINVAL;
735 break;
736 }
737
738 /* If the address parameter is not (int *)1, set the pc. */
739 if ((int *)addr != (int *)1) {
740 error = process_set_pc(lt, addr);
741 if (error != 0)
742 break;
743 }
744 #ifdef PT_STEP
745 /*
746 * Arrange for a single-step, if that's requested and possible.
747 * More precisely, set the single step status as requested for
748 * the requested thread, and clear it for other threads.
749 */
750 LIST_FOREACH(lt2, &t->p_lwps, l_sibling) {
751 if (lt != lt2) {
752 lwp_lock(lt2);
753 process_sstep(lt2, 0);
754 lwp_unlock(lt2);
755 }
756 }
757 error = process_sstep(lt, req == PT_STEP);
758 if (error)
759 break;
760 #endif
761 if (req == PT_DETACH) {
762 CLR(t->p_slflag, PSL_TRACED|PSL_FSTRACE|PSL_SYSCALL);
763
764 /* give process back to original parent or init */
765 if (t->p_opptr != t->p_pptr) {
766 struct proc *pp = t->p_opptr;
767 proc_reparent(t, pp ? pp : initproc);
768 }
769
770 /* not being traced any more */
771 t->p_opptr = NULL;
772 }
773 sendsig:
774 t->p_fpid = 0;
775 /* Finally, deliver the requested signal (or none). */
776 if (t->p_stat == SSTOP) {
777 /*
778 * Unstop the process. If it needs to take a
779 * signal, make all efforts to ensure that at
780 * an LWP runs to see it.
781 */
782 t->p_xsig = signo;
783 if (resume_all)
784 proc_unstop(t);
785 else
786 lwp_unstop(lt);
787 } else if (signo != 0) {
788 KSI_INIT_EMPTY(&ksi);
789 ksi.ksi_signo = signo;
790 kpsignal2(t, &ksi);
791 }
792 break;
793
794 case PT_SYSCALLEMU:
795 if (!ISSET(t->p_slflag, PSL_SYSCALL) || t->p_stat != SSTOP) {
796 error = EINVAL;
797 break;
798 }
799 SET(t->p_slflag, PSL_SYSCALLEMU);
800 break;
801
802 case PT_KILL:
803 /* just send the process a KILL signal. */
804 signo = SIGKILL;
805 goto sendsig; /* in PT_CONTINUE, above. */
806
807 case PT_ATTACH:
808 /*
809 * Go ahead and set the trace flag.
810 * Save the old parent (it's reset in
811 * _DETACH, and also in kern_exit.c:wait4()
812 * Reparent the process so that the tracing
813 * proc gets to see all the action.
814 * Stop the target.
815 */
816 proc_changeparent(t, p);
817 signo = SIGSTOP;
818 goto sendsig;
819
820 case PT_GET_EVENT_MASK:
821 if (data != sizeof(pe)) {
822 DPRINTF(("ptrace(%d): %d != %zu\n", req,
823 data, sizeof(pe)));
824 error = EINVAL;
825 break;
826 }
827 memset(&pe, 0, sizeof(pe));
828 pe.pe_set_event = ISSET(t->p_slflag, PSL_TRACEFORK) ?
829 PTRACE_FORK : 0;
830 error = copyout(&pe, addr, sizeof(pe));
831 break;
832
833 case PT_SET_EVENT_MASK:
834 if (data != sizeof(pe)) {
835 DPRINTF(("ptrace(%d): %d != %zu\n", req, data,
836 sizeof(pe)));
837 error = EINVAL;
838 break;
839 }
840 if ((error = copyin(addr, &pe, sizeof(pe))) != 0)
841 return error;
842 if (pe.pe_set_event & PTRACE_FORK)
843 SET(t->p_slflag, PSL_TRACEFORK);
844 else
845 CLR(t->p_slflag, PSL_TRACEFORK);
846 break;
847
848 case PT_GET_PROCESS_STATE:
849 if (data != sizeof(ps)) {
850 DPRINTF(("ptrace(%d): %d != %zu\n", req, data,
851 sizeof(ps)));
852 error = EINVAL;
853 break;
854 }
855 memset(&ps, 0, sizeof(ps));
856 if (t->p_fpid) {
857 ps.pe_report_event = PTRACE_FORK;
858 ps.pe_other_pid = t->p_fpid;
859 }
860 error = copyout(&ps, addr, sizeof(ps));
861 break;
862
863 case PT_LWPINFO:
864 if (data != sizeof(pl)) {
865 DPRINTF(("ptrace(%d): %d != %zu\n", req, data,
866 sizeof(pl)));
867 error = EINVAL;
868 break;
869 }
870 error = copyin(addr, &pl, sizeof(pl));
871 if (error)
872 break;
873 tmp = pl.pl_lwpid;
874 lwp_delref(lt);
875 mutex_enter(t->p_lock);
876 if (tmp == 0)
877 lt = lwp_find_first(t);
878 else {
879 lt = lwp_find(t, tmp);
880 if (lt == NULL) {
881 mutex_exit(t->p_lock);
882 error = ESRCH;
883 break;
884 }
885 lt = LIST_NEXT(lt, l_sibling);
886 }
887 while (lt != NULL && !lwp_alive(lt))
888 lt = LIST_NEXT(lt, l_sibling);
889 pl.pl_lwpid = 0;
890 pl.pl_event = 0;
891 if (lt) {
892 lwp_addref(lt);
893 pl.pl_lwpid = lt->l_lid;
894 if (lt->l_lid == t->p_sigctx.ps_lwp)
895 pl.pl_event = PL_EVENT_SIGNAL;
896 }
897 mutex_exit(t->p_lock);
898
899 error = copyout(&pl, addr, sizeof(pl));
900 break;
901
902 #ifdef PT_SETREGS
903 case PT_SETREGS:
904 write = 1;
905 #endif
906 #ifdef PT_GETREGS
907 case PT_GETREGS:
908 /* write = 0 done above. */
909 #endif
910 #if defined(PT_SETREGS) || defined(PT_GETREGS)
911 tmp = data;
912 if (tmp != 0 && t->p_nlwps > 1) {
913 lwp_delref(lt);
914 mutex_enter(t->p_lock);
915 lt = lwp_find(t, tmp);
916 if (lt == NULL) {
917 mutex_exit(t->p_lock);
918 error = ESRCH;
919 break;
920 }
921 lwp_addref(lt);
922 mutex_exit(t->p_lock);
923 }
924 if (!process_validregs(lt))
925 error = EINVAL;
926 else {
927 error = proc_vmspace_getref(p, &vm);
928 if (error)
929 break;
930 iov.iov_base = addr;
931 iov.iov_len = PROC_REGSZ(p);
932 uio.uio_iov = &iov;
933 uio.uio_iovcnt = 1;
934 uio.uio_offset = 0;
935 uio.uio_resid = iov.iov_len;
936 uio.uio_rw = write ? UIO_WRITE : UIO_READ;
937 uio.uio_vmspace = vm;
938
939 error = ptm->ptm_doregs(l, lt, &uio);
940 uvmspace_free(vm);
941 }
942 break;
943 #endif
944
945 #ifdef PT_SETFPREGS
946 case PT_SETFPREGS:
947 write = 1;
948 #endif
949 #ifdef PT_GETFPREGS
950 case PT_GETFPREGS:
951 /* write = 0 done above. */
952 #endif
953 #if defined(PT_SETFPREGS) || defined(PT_GETFPREGS)
954 tmp = data;
955 if (tmp != 0 && t->p_nlwps > 1) {
956 lwp_delref(lt);
957 mutex_enter(t->p_lock);
958 lt = lwp_find(t, tmp);
959 if (lt == NULL) {
960 mutex_exit(t->p_lock);
961 error = ESRCH;
962 break;
963 }
964 lwp_addref(lt);
965 mutex_exit(t->p_lock);
966 }
967 if (!process_validfpregs(lt))
968 error = EINVAL;
969 else {
970 error = proc_vmspace_getref(p, &vm);
971 if (error)
972 break;
973 iov.iov_base = addr;
974 iov.iov_len = PROC_FPREGSZ(p);
975 uio.uio_iov = &iov;
976 uio.uio_iovcnt = 1;
977 uio.uio_offset = 0;
978 uio.uio_resid = iov.iov_len;
979 uio.uio_rw = write ? UIO_WRITE : UIO_READ;
980 uio.uio_vmspace = vm;
981
982 error = ptm->ptm_dofpregs(l, lt, &uio);
983 uvmspace_free(vm);
984 }
985 break;
986 #endif
987
988 #ifdef __HAVE_PTRACE_MACHDEP
989 PTRACE_MACHDEP_REQUEST_CASES
990 error = ptrace_machdep_dorequest(l, lt, req, addr, data);
991 break;
992 #endif
993 }
994
995 if (pheld) {
996 mutex_exit(t->p_lock);
997 mutex_exit(proc_lock);
998 }
999 if (lt != NULL)
1000 lwp_delref(lt);
1001 rw_exit(&t->p_reflock);
1002
1003 return error;
1004 }
1005
1006 int
1007 process_doregs(struct lwp *curl /*tracer*/,
1008 struct lwp *l /*traced*/,
1009 struct uio *uio)
1010 {
1011 #if defined(PT_GETREGS) || defined(PT_SETREGS)
1012 int error;
1013 struct reg r;
1014 char *kv;
1015 int kl;
1016
1017 if (uio->uio_offset < 0 || uio->uio_offset > (off_t)sizeof(r))
1018 return EINVAL;
1019
1020 kl = sizeof(r);
1021 kv = (char *)&r;
1022
1023 kv += uio->uio_offset;
1024 kl -= uio->uio_offset;
1025 if ((size_t)kl > uio->uio_resid)
1026 kl = uio->uio_resid;
1027
1028 error = process_read_regs(l, &r);
1029 if (error == 0)
1030 error = uiomove(kv, kl, uio);
1031 if (error == 0 && uio->uio_rw == UIO_WRITE) {
1032 if (l->l_stat != LSSTOP)
1033 error = EBUSY;
1034 else
1035 error = process_write_regs(l, &r);
1036 }
1037
1038 uio->uio_offset = 0;
1039 return error;
1040 #else
1041 return EINVAL;
1042 #endif
1043 }
1044
1045 int
1046 process_validregs(struct lwp *l)
1047 {
1048
1049 #if defined(PT_SETREGS) || defined(PT_GETREGS)
1050 return (l->l_flag & LW_SYSTEM) == 0;
1051 #else
1052 return 0;
1053 #endif
1054 }
1055
1056 int
1057 process_dofpregs(struct lwp *curl /*tracer*/,
1058 struct lwp *l /*traced*/,
1059 struct uio *uio)
1060 {
1061 #if defined(PT_GETFPREGS) || defined(PT_SETFPREGS)
1062 int error;
1063 struct fpreg r;
1064 char *kv;
1065 size_t kl;
1066
1067 if (uio->uio_offset < 0 || uio->uio_offset > (off_t)sizeof(r))
1068 return EINVAL;
1069
1070 kl = sizeof(r);
1071 kv = (char *)&r;
1072
1073 kv += uio->uio_offset;
1074 kl -= uio->uio_offset;
1075 if (kl > uio->uio_resid)
1076 kl = uio->uio_resid;
1077
1078 error = process_read_fpregs(l, &r, &kl);
1079 if (error == 0)
1080 error = uiomove(kv, kl, uio);
1081 if (error == 0 && uio->uio_rw == UIO_WRITE) {
1082 if (l->l_stat != LSSTOP)
1083 error = EBUSY;
1084 else
1085 error = process_write_fpregs(l, &r, kl);
1086 }
1087 uio->uio_offset = 0;
1088 return error;
1089 #else
1090 return EINVAL;
1091 #endif
1092 }
1093
1094 int
1095 process_validfpregs(struct lwp *l)
1096 {
1097
1098 #if defined(PT_SETFPREGS) || defined(PT_GETFPREGS)
1099 return (l->l_flag & LW_SYSTEM) == 0;
1100 #else
1101 return 0;
1102 #endif
1103 }
1104
1105 static int
1106 process_auxv_offset(struct proc *p, struct uio *uio)
1107 {
1108 struct ps_strings pss;
1109 int error;
1110 off_t off = (off_t)p->p_psstrp;
1111
1112 if ((error = copyin_psstrings(p, &pss)) != 0)
1113 return error;
1114
1115 if (pss.ps_envstr == NULL)
1116 return EIO;
1117
1118 uio->uio_offset += (off_t)(vaddr_t)(pss.ps_envstr + pss.ps_nenvstr + 1);
1119 #ifdef __MACHINE_STACK_GROWS_UP
1120 if (uio->uio_offset < off)
1121 return EIO;
1122 #else
1123 if (uio->uio_offset > off)
1124 return EIO;
1125 if ((uio->uio_offset + uio->uio_resid) > off)
1126 uio->uio_resid = off - uio->uio_offset;
1127 #endif
1128 return 0;
1129 }
1130 #endif /* PTRACE */
1131
1132 MODULE(MODULE_CLASS_EXEC, ptrace_common, "");
1133
1134 static int
1135 ptrace_common_modcmd(modcmd_t cmd, void *arg)
1136 {
1137 int error;
1138
1139 switch (cmd) {
1140 case MODULE_CMD_INIT:
1141 error = ptrace_init();
1142 break;
1143 case MODULE_CMD_FINI:
1144 error = ptrace_fini();
1145 break;
1146 default:
1147 ptrace_hooks();
1148 error = ENOTTY;
1149 break;
1150 }
1151 return error;
1152 }
1153
1154