xref: /netbsd-src/lib/libkvm/kvm_proc.c (revision 53b02e147d4ed531c0d2a5ca9b3e8026ba3e99b5)
1 /*	$NetBSD: kvm_proc.c,v 1.95 2021/07/19 10:30:36 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 1998 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Charles M. Hannum.
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) 1989, 1992, 1993
34  *	The Regents of the University of California.  All rights reserved.
35  *
36  * This code is derived from software developed by the Computer Systems
37  * Engineering group at Lawrence Berkeley Laboratory under DARPA contract
38  * BG 91-66 and contributed to Berkeley.
39  *
40  * Redistribution and use in source and binary forms, with or without
41  * modification, are permitted provided that the following conditions
42  * are met:
43  * 1. Redistributions of source code must retain the above copyright
44  *    notice, this list of conditions and the following disclaimer.
45  * 2. Redistributions in binary form must reproduce the above copyright
46  *    notice, this list of conditions and the following disclaimer in the
47  *    documentation and/or other materials provided with the distribution.
48  * 3. Neither the name of the University nor the names of its contributors
49  *    may be used to endorse or promote products derived from this software
50  *    without specific prior written permission.
51  *
52  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62  * SUCH DAMAGE.
63  */
64 
65 #include <sys/cdefs.h>
66 #if defined(LIBC_SCCS) && !defined(lint)
67 #if 0
68 static char sccsid[] = "@(#)kvm_proc.c	8.3 (Berkeley) 9/23/93";
69 #else
70 __RCSID("$NetBSD: kvm_proc.c,v 1.95 2021/07/19 10:30:36 christos Exp $");
71 #endif
72 #endif /* LIBC_SCCS and not lint */
73 
74 /*
75  * Proc traversal interface for kvm.  ps and w are (probably) the exclusive
76  * users of this code, so we've factored it out into a separate module.
77  * Thus, we keep this grunge out of the other kvm applications (i.e.,
78  * most other applications are interested only in open/close/read/nlist).
79  */
80 
81 #include <sys/param.h>
82 #include <sys/lwp.h>
83 #include <sys/wait.h>
84 #include <sys/proc.h>
85 #include <sys/exec.h>
86 #include <sys/stat.h>
87 #include <sys/ioctl.h>
88 #include <sys/tty.h>
89 #include <sys/resourcevar.h>
90 #include <sys/mutex.h>
91 #include <sys/specificdata.h>
92 #include <sys/types.h>
93 
94 #include <errno.h>
95 #include <stdlib.h>
96 #include <stddef.h>
97 #include <string.h>
98 #include <unistd.h>
99 #include <nlist.h>
100 #include <kvm.h>
101 
102 #include <uvm/uvm_extern.h>
103 #include <uvm/uvm_param.h>
104 #include <uvm/uvm_amap.h>
105 #include <uvm/uvm_page.h>
106 
107 #include <sys/sysctl.h>
108 
109 #include <limits.h>
110 #include <db.h>
111 #include <paths.h>
112 
113 #include "kvm_private.h"
114 
115 /*
116  * Common info from kinfo_proc and kinfo_proc2 used by helper routines.
117  */
118 struct miniproc {
119 	struct	vmspace *p_vmspace;
120 	char	p_stat;
121 	struct	proc *p_paddr;
122 	pid_t	p_pid;
123 };
124 
125 /*
126  * Convert from struct proc and kinfo_proc{,2} to miniproc.
127  */
128 #define PTOMINI(kp, p) \
129 	do { \
130 		(p)->p_stat = (kp)->p_stat; \
131 		(p)->p_pid = (kp)->p_pid; \
132 		(p)->p_paddr = NULL; \
133 		(p)->p_vmspace = (kp)->p_vmspace; \
134 	} while (/*CONSTCOND*/0);
135 
136 #define KPTOMINI(kp, p) \
137 	do { \
138 		(p)->p_stat = (kp)->kp_proc.p_stat; \
139 		(p)->p_pid = (kp)->kp_proc.p_pid; \
140 		(p)->p_paddr = (kp)->kp_eproc.e_paddr; \
141 		(p)->p_vmspace = (kp)->kp_proc.p_vmspace; \
142 	} while (/*CONSTCOND*/0);
143 
144 #define KP2TOMINI(kp, p) \
145 	do { \
146 		(p)->p_stat = (kp)->p_stat; \
147 		(p)->p_pid = (kp)->p_pid; \
148 		(p)->p_paddr = (void *)(long)(kp)->p_paddr; \
149 		(p)->p_vmspace = (void *)(long)(kp)->p_vmspace; \
150 	} while (/*CONSTCOND*/0);
151 
152 /*
153  * NetBSD uses kauth(9) to manage credentials, which are stored in kauth_cred_t,
154  * a kernel-only opaque type. This is an embedded version which is *INTERNAL* to
155  * kvm(3) so dumps can be read properly.
156  *
157  * Whenever NetBSD starts exporting credentials to userland consistently (using
158  * 'struct uucred', or something) this will have to be updated again.
159  */
160 struct kvm_kauth_cred {
161 	u_int cr_refcnt;		/* reference count */
162 #if COHERENCY_UNIT > 4
163 	uint8_t cr_pad[COHERENCY_UNIT - 4];
164 #endif
165 	uid_t cr_uid;			/* user id */
166 	uid_t cr_euid;			/* effective user id */
167 	uid_t cr_svuid;			/* saved effective user id */
168 	gid_t cr_gid;			/* group id */
169 	gid_t cr_egid;			/* effective group id */
170 	gid_t cr_svgid;			/* saved effective group id */
171 	u_int cr_ngroups;		/* number of groups */
172 	gid_t cr_groups[NGROUPS];	/* group memberships */
173 	specificdata_reference cr_sd;	/* specific data */
174 };
175 
176 /* XXX: What uses these two functions? */
177 char		*_kvm_uread(kvm_t *, const struct proc *, u_long, u_long *);
178 ssize_t		kvm_uread(kvm_t *, const struct proc *, u_long, char *,
179 		    size_t);
180 
181 static char	*_kvm_ureadm(kvm_t *, const struct miniproc *, u_long,
182 		    u_long *);
183 static ssize_t	kvm_ureadm(kvm_t *, const struct miniproc *, u_long,
184 		    char *, size_t);
185 
186 static char	**kvm_argv(kvm_t *, const struct miniproc *, u_long, int, int);
187 static int	kvm_deadprocs(kvm_t *, int, int, u_long, u_long, int);
188 static char	**kvm_doargv(kvm_t *, const struct miniproc *, int,
189 		    void (*)(struct ps_strings *, u_long *, int *));
190 static char	**kvm_doargv2(kvm_t *, pid_t, int, int);
191 static int	kvm_proclist(kvm_t *, int, int, struct proc *,
192 		    struct kinfo_proc *, int);
193 static int	proc_verify(kvm_t *, u_long, const struct miniproc *);
194 static void	ps_str_a(struct ps_strings *, u_long *, int *);
195 static void	ps_str_e(struct ps_strings *, u_long *, int *);
196 
197 
198 static char *
199 _kvm_ureadm(kvm_t *kd, const struct miniproc *p, u_long va, u_long *cnt)
200 {
201 	u_long addr, head;
202 	u_long offset;
203 	struct vm_map_entry vme;
204 	struct vm_amap amap;
205 	struct vm_anon *anonp, anon;
206 	struct vm_page pg;
207 	u_long slot;
208 
209 	if (kd->swapspc == NULL) {
210 		kd->swapspc = _kvm_malloc(kd, (size_t)kd->nbpg);
211 		if (kd->swapspc == NULL)
212 			return (NULL);
213 	}
214 
215 	/*
216 	 * Look through the address map for the memory object
217 	 * that corresponds to the given virtual address.
218 	 * The header just has the entire valid range.
219 	 */
220 	head = (u_long)&p->p_vmspace->vm_map.header;
221 	addr = head;
222 	for (;;) {
223 		if (KREAD(kd, addr, &vme))
224 			return (NULL);
225 
226 		if (va >= vme.start && va < vme.end &&
227 		    vme.aref.ar_amap != NULL)
228 			break;
229 
230 		addr = (u_long)vme.next;
231 		if (addr == head)
232 			return (NULL);
233 	}
234 
235 	/*
236 	 * we found the map entry, now to find the object...
237 	 */
238 	if (vme.aref.ar_amap == NULL)
239 		return (NULL);
240 
241 	addr = (u_long)vme.aref.ar_amap;
242 	if (KREAD(kd, addr, &amap))
243 		return (NULL);
244 
245 	offset = va - vme.start;
246 	slot = offset / kd->nbpg + vme.aref.ar_pageoff;
247 	/* sanity-check slot number */
248 	if (slot > amap.am_nslot)
249 		return (NULL);
250 
251 	addr = (u_long)amap.am_anon + (offset / kd->nbpg) * sizeof(anonp);
252 	if (KREAD(kd, addr, &anonp))
253 		return (NULL);
254 
255 	addr = (u_long)anonp;
256 	if (KREAD(kd, addr, &anon))
257 		return (NULL);
258 
259 	addr = (u_long)anon.an_page;
260 	if (addr) {
261 		if (KREAD(kd, addr, &pg))
262 			return (NULL);
263 
264 		if (_kvm_pread(kd, kd->pmfd, kd->swapspc, (size_t)kd->nbpg,
265 		    (off_t)pg.phys_addr & ~(kd->nbpg - 1)) != kd->nbpg)
266 			return (NULL);
267 	} else {
268 		if (kd->swfd < 0 ||
269 		    _kvm_pread(kd, kd->swfd, kd->swapspc, (size_t)kd->nbpg,
270 		    (off_t)(anon.an_swslot * kd->nbpg)) != kd->nbpg)
271 			return (NULL);
272 	}
273 
274 	/* Found the page. */
275 	offset %= kd->nbpg;
276 	*cnt = kd->nbpg - offset;
277 	return (&kd->swapspc[(size_t)offset]);
278 }
279 
280 char *
281 _kvm_uread(kvm_t *kd, const struct proc *p, u_long va, u_long *cnt)
282 {
283 	struct miniproc mp;
284 
285 	PTOMINI(p, &mp);
286 	return (_kvm_ureadm(kd, &mp, va, cnt));
287 }
288 
289 /*
290  * Convert credentials located in kernel space address 'cred' and store
291  * them in the appropriate members of 'eproc'.
292  */
293 static int
294 _kvm_convertcred(kvm_t *kd, u_long cred, struct eproc *eproc)
295 {
296 	struct kvm_kauth_cred kauthcred;
297 	struct ki_pcred *pc = &eproc->e_pcred;
298 	struct ki_ucred *uc = &eproc->e_ucred;
299 
300 	if (KREAD(kd, cred, &kauthcred) != 0)
301 		return (-1);
302 
303 	/* inlined version of kauth_cred_to_pcred, see kauth(9). */
304 	pc->p_ruid = kauthcred.cr_uid;
305 	pc->p_svuid = kauthcred.cr_svuid;
306 	pc->p_rgid = kauthcred.cr_gid;
307 	pc->p_svgid = kauthcred.cr_svgid;
308 	pc->p_refcnt = kauthcred.cr_refcnt;
309 	pc->p_pad = NULL;
310 
311 	/* inlined version of kauth_cred_to_ucred(), see kauth(9). */
312 	uc->cr_ref = kauthcred.cr_refcnt;
313 	uc->cr_uid = kauthcred.cr_euid;
314 	uc->cr_gid = kauthcred.cr_egid;
315 	uc->cr_ngroups = (uint32_t)MIN(kauthcred.cr_ngroups,
316 	    sizeof(uc->cr_groups) / sizeof(uc->cr_groups[0]));
317 	memcpy(uc->cr_groups, kauthcred.cr_groups,
318 	    uc->cr_ngroups * sizeof(uc->cr_groups[0]));
319 
320 	return (0);
321 }
322 
323 /*
324  * Read proc's from memory file into buffer bp, which has space to hold
325  * at most maxcnt procs.
326  */
327 static int
328 kvm_proclist(kvm_t *kd, int what, int arg, struct proc *p,
329 	     struct kinfo_proc *bp, int maxcnt)
330 {
331 	int cnt = 0;
332 	int nlwps;
333 	struct kinfo_lwp *kl;
334 	struct eproc eproc;
335 	struct pgrp pgrp;
336 	struct session sess;
337 	struct tty tty;
338 	struct proc proc;
339 
340 	for (; cnt < maxcnt && p != NULL; p = proc.p_list.le_next) {
341 		if (KREAD(kd, (u_long)p, &proc)) {
342 			_kvm_err(kd, kd->program, "can't read proc at %p", p);
343 			return (-1);
344 		}
345 		if (_kvm_convertcred(kd, (u_long)proc.p_cred, &eproc) != 0) {
346 			_kvm_err(kd, kd->program,
347 			    "can't read proc credentials at %p", p);
348 			return (-1);
349 		}
350 
351 		switch (what) {
352 
353 		case KERN_PROC_PID:
354 			if (proc.p_pid != (pid_t)arg)
355 				continue;
356 			break;
357 
358 		case KERN_PROC_UID:
359 			if (eproc.e_ucred.cr_uid != (uid_t)arg)
360 				continue;
361 			break;
362 
363 		case KERN_PROC_RUID:
364 			if (eproc.e_pcred.p_ruid != (uid_t)arg)
365 				continue;
366 			break;
367 		}
368 		/*
369 		 * We're going to add another proc to the set.  If this
370 		 * will overflow the buffer, assume the reason is because
371 		 * nprocs (or the proc list) is corrupt and declare an error.
372 		 */
373 		if (cnt >= maxcnt) {
374 			_kvm_err(kd, kd->program, "nprocs corrupt");
375 			return (-1);
376 		}
377 		/*
378 		 * gather eproc
379 		 */
380 		eproc.e_paddr = p;
381 		if (KREAD(kd, (u_long)proc.p_pgrp, &pgrp)) {
382 			_kvm_err(kd, kd->program, "can't read pgrp at %p",
383 			    proc.p_pgrp);
384 			return (-1);
385 		}
386 		eproc.e_sess = pgrp.pg_session;
387 		eproc.e_pgid = pgrp.pg_id;
388 		eproc.e_jobc = pgrp.pg_jobc;
389 		if (KREAD(kd, (u_long)pgrp.pg_session, &sess)) {
390 			_kvm_err(kd, kd->program, "can't read session at %p",
391 			    pgrp.pg_session);
392 			return (-1);
393 		}
394 		if ((proc.p_lflag & PL_CONTROLT) && sess.s_ttyp != NULL) {
395 			if (KREAD(kd, (u_long)sess.s_ttyp, &tty)) {
396 				_kvm_err(kd, kd->program,
397 				    "can't read tty at %p", sess.s_ttyp);
398 				return (-1);
399 			}
400 			eproc.e_tdev = (uint32_t)tty.t_dev;
401 			eproc.e_tsess = tty.t_session;
402 			if (tty.t_pgrp != NULL) {
403 				if (KREAD(kd, (u_long)tty.t_pgrp, &pgrp)) {
404 					_kvm_err(kd, kd->program,
405 					    "can't read tpgrp at %p",
406 					    tty.t_pgrp);
407 					return (-1);
408 				}
409 				eproc.e_tpgid = pgrp.pg_id;
410 			} else
411 				eproc.e_tpgid = -1;
412 		} else
413 			eproc.e_tdev = (uint32_t)NODEV;
414 		eproc.e_flag = sess.s_ttyvp ? EPROC_CTTY : 0;
415 		eproc.e_sid = sess.s_sid;
416 		if (sess.s_leader == p)
417 			eproc.e_flag |= EPROC_SLEADER;
418 		/*
419 		 * Fill in the old-style proc.p_wmesg by copying the wmesg
420 		 * from the first available LWP.
421 		 */
422 		kl = kvm_getlwps(kd, proc.p_pid,
423 		    (u_long)PTRTOUINT64(eproc.e_paddr),
424 		    sizeof(struct kinfo_lwp), &nlwps);
425 		if (kl) {
426 			if (nlwps > 0) {
427 				strcpy(eproc.e_wmesg, kl[0].l_wmesg);
428 			}
429 		}
430 		(void)kvm_read(kd, (u_long)proc.p_vmspace, &eproc.e_vm,
431 		    sizeof(eproc.e_vm));
432 
433 		eproc.e_xsize = eproc.e_xrssize = 0;
434 		eproc.e_xccount = eproc.e_xswrss = 0;
435 
436 		switch (what) {
437 
438 		case KERN_PROC_PGRP:
439 			if (eproc.e_pgid != (pid_t)arg)
440 				continue;
441 			break;
442 
443 		case KERN_PROC_TTY:
444 			if ((proc.p_lflag & PL_CONTROLT) == 0 ||
445 			    eproc.e_tdev != (dev_t)arg)
446 				continue;
447 			break;
448 		}
449 		memcpy(&bp->kp_proc, &proc, sizeof(proc));
450 		memcpy(&bp->kp_eproc, &eproc, sizeof(eproc));
451 		++bp;
452 		++cnt;
453 	}
454 	return (cnt);
455 }
456 
457 /*
458  * Build proc info array by reading in proc list from a crash dump.
459  * Return number of procs read.  maxcnt is the max we will read.
460  */
461 static int
462 kvm_deadprocs(kvm_t *kd, int what, int arg, u_long a_allproc,
463 	      u_long a_zombproc, int maxcnt)
464 {
465 	struct kinfo_proc *bp = kd->procbase;
466 	int acnt, zcnt;
467 	struct proc *p;
468 
469 	if (KREAD(kd, a_allproc, &p)) {
470 		_kvm_err(kd, kd->program, "cannot read allproc");
471 		return (-1);
472 	}
473 	acnt = kvm_proclist(kd, what, arg, p, bp, maxcnt);
474 	if (acnt < 0)
475 		return (acnt);
476 
477 	if (KREAD(kd, a_zombproc, &p)) {
478 		_kvm_err(kd, kd->program, "cannot read zombproc");
479 		return (-1);
480 	}
481 	zcnt = kvm_proclist(kd, what, arg, p, bp + acnt,
482 	    maxcnt - acnt);
483 	if (zcnt < 0)
484 		zcnt = 0;
485 
486 	return (acnt + zcnt);
487 }
488 
489 struct kinfo_proc2 *
490 kvm_getproc2(kvm_t *kd, int op, int arg, size_t esize, int *cnt)
491 {
492 	size_t size;
493 	int mib[6], st, nprocs;
494 	struct pstats pstats;
495 
496 	if (ISSYSCTL(kd)) {
497 		size = 0;
498 		mib[0] = CTL_KERN;
499 		mib[1] = KERN_PROC2;
500 		mib[2] = op;
501 		mib[3] = arg;
502 		mib[4] = (int)esize;
503 again:
504 		mib[5] = 0;
505 		st = sysctl(mib, 6, NULL, &size, NULL, (size_t)0);
506 		if (st == -1) {
507 			_kvm_syserr(kd, kd->program, "kvm_getproc2");
508 			return (NULL);
509 		}
510 
511 		mib[5] = (int) (size / esize);
512 		KVM_ALLOC(kd, procbase2, size);
513 		st = sysctl(mib, 6, kd->procbase2, &size, NULL, (size_t)0);
514 		if (st == -1) {
515 			if (errno == ENOMEM) {
516 				goto again;
517 			}
518 			_kvm_syserr(kd, kd->program, "kvm_getproc2");
519 			return (NULL);
520 		}
521 		nprocs = (int) (size / esize);
522 	} else {
523 		char *kp2c;
524 		struct kinfo_proc *kp;
525 		struct kinfo_proc2 kp2, *kp2p;
526 		struct kinfo_lwp *kl;
527 		int i, nlwps;
528 
529 		kp = kvm_getprocs(kd, op, arg, &nprocs);
530 		if (kp == NULL)
531 			return (NULL);
532 
533 		size = nprocs * esize;
534 		KVM_ALLOC(kd, procbase2, size);
535 		kp2c = (char *)(void *)kd->procbase2;
536 		kp2p = &kp2;
537 		for (i = 0; i < nprocs; i++, kp++) {
538 			struct timeval tv;
539 
540 			kl = kvm_getlwps(kd, kp->kp_proc.p_pid,
541 			    (u_long)PTRTOUINT64(kp->kp_eproc.e_paddr),
542 			    sizeof(struct kinfo_lwp), &nlwps);
543 
544 			if (kl == NULL) {
545 				_kvm_syserr(kd, NULL,
546 					"kvm_getlwps() failed on process %u\n",
547 					kp->kp_proc.p_pid);
548 				if (nlwps == 0)
549 					return NULL;
550 				else
551 					continue;
552 			}
553 
554 			/* We use kl[0] as the "representative" LWP */
555 			memset(kp2p, 0, sizeof(kp2));
556 			kp2p->p_forw = kl[0].l_forw;
557 			kp2p->p_back = kl[0].l_back;
558 			kp2p->p_paddr = PTRTOUINT64(kp->kp_eproc.e_paddr);
559 			kp2p->p_addr = kl[0].l_addr;
560 			kp2p->p_fd = PTRTOUINT64(kp->kp_proc.p_fd);
561 			kp2p->p_cwdi = PTRTOUINT64(kp->kp_proc.p_cwdi);
562 			kp2p->p_stats = PTRTOUINT64(kp->kp_proc.p_stats);
563 			kp2p->p_limit = PTRTOUINT64(kp->kp_proc.p_limit);
564 			kp2p->p_vmspace = PTRTOUINT64(kp->kp_proc.p_vmspace);
565 			kp2p->p_sigacts = PTRTOUINT64(kp->kp_proc.p_sigacts);
566 			kp2p->p_sess = PTRTOUINT64(kp->kp_eproc.e_sess);
567 			kp2p->p_tsess = 0;
568 #if 1 /* XXX: dsl - p_ru was only ever non-zero for zombies */
569 			kp2p->p_ru = 0;
570 #else
571 			kp2p->p_ru = PTRTOUINT64(pstats.p_ru);
572 #endif
573 
574 			kp2p->p_eflag = 0;
575 			kp2p->p_exitsig = kp->kp_proc.p_exitsig;
576 			kp2p->p_flag = kp->kp_proc.p_flag;
577 
578 			kp2p->p_pid = kp->kp_proc.p_pid;
579 
580 			kp2p->p_ppid = kp->kp_eproc.e_ppid;
581 			kp2p->p_sid = kp->kp_eproc.e_sid;
582 			kp2p->p__pgid = kp->kp_eproc.e_pgid;
583 
584 			kp2p->p_tpgid = -1 /* XXX NO_PGID! */;
585 
586 			kp2p->p_uid = kp->kp_eproc.e_ucred.cr_uid;
587 			kp2p->p_ruid = kp->kp_eproc.e_pcred.p_ruid;
588 			kp2p->p_svuid = kp->kp_eproc.e_pcred.p_svuid;
589 			kp2p->p_gid = kp->kp_eproc.e_ucred.cr_gid;
590 			kp2p->p_rgid = kp->kp_eproc.e_pcred.p_rgid;
591 			kp2p->p_svgid = kp->kp_eproc.e_pcred.p_svgid;
592 
593 			/*CONSTCOND*/
594 			memcpy(kp2p->p_groups, kp->kp_eproc.e_ucred.cr_groups,
595 			    MIN(sizeof(kp2p->p_groups),
596 			    sizeof(kp->kp_eproc.e_ucred.cr_groups)));
597 			kp2p->p_ngroups = kp->kp_eproc.e_ucred.cr_ngroups;
598 
599 			kp2p->p_jobc = kp->kp_eproc.e_jobc;
600 			kp2p->p_tdev = kp->kp_eproc.e_tdev;
601 			kp2p->p_tpgid = kp->kp_eproc.e_tpgid;
602 			kp2p->p_tsess = PTRTOUINT64(kp->kp_eproc.e_tsess);
603 
604 			kp2p->p_estcpu = 0;
605 			bintime2timeval(&kp->kp_proc.p_rtime, &tv);
606 			kp2p->p_rtime_sec = (uint32_t)tv.tv_sec;
607 			kp2p->p_rtime_usec = (uint32_t)tv.tv_usec;
608 			kp2p->p_cpticks = kl[0].l_cpticks;
609 			kp2p->p_pctcpu = kp->kp_proc.p_pctcpu;
610 			kp2p->p_swtime = kl[0].l_swtime;
611 			kp2p->p_slptime = kl[0].l_slptime;
612 #if 0 /* XXX thorpej */
613 			kp2p->p_schedflags = kp->kp_proc.p_schedflags;
614 #else
615 			kp2p->p_schedflags = 0;
616 #endif
617 
618 			kp2p->p_uticks = kp->kp_proc.p_uticks;
619 			kp2p->p_sticks = kp->kp_proc.p_sticks;
620 			kp2p->p_iticks = kp->kp_proc.p_iticks;
621 
622 			kp2p->p_tracep = PTRTOUINT64(kp->kp_proc.p_tracep);
623 			kp2p->p_traceflag = kp->kp_proc.p_traceflag;
624 
625 			kp2p->p_holdcnt = kl[0].l_holdcnt;
626 
627 			memcpy(&kp2p->p_siglist,
628 			    &kp->kp_proc.p_sigpend.sp_set,
629 			    sizeof(ki_sigset_t));
630 			memset(&kp2p->p_sigmask, 0,
631 			    sizeof(ki_sigset_t));
632 			memcpy(&kp2p->p_sigignore,
633 			    &kp->kp_proc.p_sigctx.ps_sigignore,
634 			    sizeof(ki_sigset_t));
635 			memcpy(&kp2p->p_sigcatch,
636 			    &kp->kp_proc.p_sigctx.ps_sigcatch,
637 			    sizeof(ki_sigset_t));
638 
639 			kp2p->p_stat = kl[0].l_stat;
640 			kp2p->p_priority = kl[0].l_priority;
641 			kp2p->p_usrpri = kl[0].l_priority;
642 			kp2p->p_nice = kp->kp_proc.p_nice;
643 
644 			kp2p->p_xstat = P_WAITSTATUS(&kp->kp_proc);
645 			kp2p->p_acflag = kp->kp_proc.p_acflag;
646 
647 			/*CONSTCOND*/
648 			strncpy(kp2p->p_comm, kp->kp_proc.p_comm,
649 			    MIN(sizeof(kp2p->p_comm),
650 			    sizeof(kp->kp_proc.p_comm)));
651 
652 			strncpy(kp2p->p_wmesg, kp->kp_eproc.e_wmesg,
653 			    sizeof(kp2p->p_wmesg));
654 			kp2p->p_wchan = kl[0].l_wchan;
655 			strncpy(kp2p->p_login, kp->kp_eproc.e_login,
656 			    sizeof(kp2p->p_login));
657 
658 			kp2p->p_vm_rssize = kp->kp_eproc.e_xrssize;
659 			kp2p->p_vm_tsize = kp->kp_eproc.e_vm.vm_tsize;
660 			kp2p->p_vm_dsize = kp->kp_eproc.e_vm.vm_dsize;
661 			kp2p->p_vm_ssize = kp->kp_eproc.e_vm.vm_ssize;
662 			kp2p->p_vm_vsize = kp->kp_eproc.e_vm.vm_map.size
663 			    / kd->nbpg;
664 			/* Adjust mapped size */
665 			kp2p->p_vm_msize =
666 			    (kp->kp_eproc.e_vm.vm_map.size / kd->nbpg) -
667 			    kp->kp_eproc.e_vm.vm_issize +
668 			    kp->kp_eproc.e_vm.vm_ssize;
669 
670 			kp2p->p_eflag = (int32_t)kp->kp_eproc.e_flag;
671 
672 			kp2p->p_realflag = kp->kp_proc.p_flag;
673 			kp2p->p_nlwps = kp->kp_proc.p_nlwps;
674 			kp2p->p_nrlwps = kp->kp_proc.p_nrlwps;
675 			kp2p->p_realstat = kp->kp_proc.p_stat;
676 
677 			if (P_ZOMBIE(&kp->kp_proc) ||
678 			    kp->kp_proc.p_stats == NULL ||
679 			    KREAD(kd, (u_long)kp->kp_proc.p_stats, &pstats)) {
680 				kp2p->p_uvalid = 0;
681 			} else {
682 				kp2p->p_uvalid = 1;
683 
684 				kp2p->p_ustart_sec = (u_int32_t)
685 				    pstats.p_start.tv_sec;
686 				kp2p->p_ustart_usec = (u_int32_t)
687 				    pstats.p_start.tv_usec;
688 
689 				kp2p->p_uutime_sec = (u_int32_t)
690 				    pstats.p_ru.ru_utime.tv_sec;
691 				kp2p->p_uutime_usec = (u_int32_t)
692 				    pstats.p_ru.ru_utime.tv_usec;
693 				kp2p->p_ustime_sec = (u_int32_t)
694 				    pstats.p_ru.ru_stime.tv_sec;
695 				kp2p->p_ustime_usec = (u_int32_t)
696 				    pstats.p_ru.ru_stime.tv_usec;
697 
698 				kp2p->p_uru_maxrss = pstats.p_ru.ru_maxrss;
699 				kp2p->p_uru_ixrss = pstats.p_ru.ru_ixrss;
700 				kp2p->p_uru_idrss = pstats.p_ru.ru_idrss;
701 				kp2p->p_uru_isrss = pstats.p_ru.ru_isrss;
702 				kp2p->p_uru_minflt = pstats.p_ru.ru_minflt;
703 				kp2p->p_uru_majflt = pstats.p_ru.ru_majflt;
704 				kp2p->p_uru_nswap = pstats.p_ru.ru_nswap;
705 				kp2p->p_uru_inblock = pstats.p_ru.ru_inblock;
706 				kp2p->p_uru_oublock = pstats.p_ru.ru_oublock;
707 				kp2p->p_uru_msgsnd = pstats.p_ru.ru_msgsnd;
708 				kp2p->p_uru_msgrcv = pstats.p_ru.ru_msgrcv;
709 				kp2p->p_uru_nsignals = pstats.p_ru.ru_nsignals;
710 				kp2p->p_uru_nvcsw = pstats.p_ru.ru_nvcsw;
711 				kp2p->p_uru_nivcsw = pstats.p_ru.ru_nivcsw;
712 
713 				kp2p->p_uctime_sec = (u_int32_t)
714 				    (pstats.p_cru.ru_utime.tv_sec +
715 				    pstats.p_cru.ru_stime.tv_sec);
716 				kp2p->p_uctime_usec = (u_int32_t)
717 				    (pstats.p_cru.ru_utime.tv_usec +
718 				    pstats.p_cru.ru_stime.tv_usec);
719 			}
720 
721 			memcpy(kp2c, &kp2, esize);
722 			kp2c += esize;
723 		}
724 	}
725 	*cnt = nprocs;
726 	return (kd->procbase2);
727 }
728 
729 struct kinfo_lwp *
730 kvm_getlwps(kvm_t *kd, int pid, u_long paddr, size_t esize, int *cnt)
731 {
732 	size_t size;
733 	int mib[5], nlwps;
734 	ssize_t st;
735 	struct kinfo_lwp *kl;
736 
737 	if (ISSYSCTL(kd)) {
738 		size = 0;
739 		mib[0] = CTL_KERN;
740 		mib[1] = KERN_LWP;
741 		mib[2] = pid;
742 		mib[3] = (int)esize;
743 		mib[4] = 0;
744 again:
745 		st = sysctl(mib, 5, NULL, &size, NULL, (size_t)0);
746 		if (st == -1) {
747 			switch (errno) {
748 			case ESRCH: /* Treat this as a soft error; see kvm.c */
749 				_kvm_syserr(kd, NULL, "kvm_getlwps");
750 				return NULL;
751 			default:
752 				_kvm_syserr(kd, kd->program, "kvm_getlwps");
753 				return NULL;
754 			}
755 		}
756 		mib[4] = (int) (size / esize);
757 		KVM_ALLOC(kd, lwpbase, size);
758 		st = sysctl(mib, 5, kd->lwpbase, &size, NULL, (size_t)0);
759 		if (st == -1) {
760 			switch (errno) {
761 			case ESRCH: /* Treat this as a soft error; see kvm.c */
762 				_kvm_syserr(kd, NULL, "kvm_getlwps");
763 				return NULL;
764 			case ENOMEM:
765 				goto again;
766 			default:
767 				_kvm_syserr(kd, kd->program, "kvm_getlwps");
768 				return NULL;
769 			}
770 		}
771 		nlwps = (int) (size / esize);
772 	} else {
773 		/* grovel through the memory image */
774 		struct proc p;
775 		struct lwp l;
776 		u_long laddr;
777 		void *back;
778 		int i;
779 
780 		st = kvm_read(kd, paddr, &p, sizeof(p));
781 		if (st == -1) {
782 			_kvm_syserr(kd, kd->program, "kvm_getlwps");
783 			return (NULL);
784 		}
785 
786 		nlwps = p.p_nlwps;
787 		size = nlwps * sizeof(*kd->lwpbase);
788 		KVM_ALLOC(kd, lwpbase, size);
789 		laddr = (u_long)PTRTOUINT64(p.p_lwps.lh_first);
790 		for (i = 0; (i < nlwps) && (laddr != 0); i++) {
791 			st = kvm_read(kd, laddr, &l, sizeof(l));
792 			if (st == -1) {
793 				_kvm_syserr(kd, kd->program, "kvm_getlwps");
794 				return (NULL);
795 			}
796 			kl = &kd->lwpbase[i];
797 			kl->l_laddr = laddr;
798 			kl->l_forw = PTRTOUINT64(l.l_runq.tqe_next);
799 			laddr = (u_long)PTRTOUINT64(l.l_runq.tqe_prev);
800 			st = kvm_read(kd, laddr, &back, sizeof(back));
801 			if (st == -1) {
802 				_kvm_syserr(kd, kd->program, "kvm_getlwps");
803 				return (NULL);
804 			}
805 			kl->l_back = PTRTOUINT64(back);
806 			kl->l_addr = PTRTOUINT64(l.l_addr);
807 			kl->l_lid = l.l_lid;
808 			kl->l_flag = l.l_flag;
809 			kl->l_swtime = l.l_swtime;
810 			kl->l_slptime = l.l_slptime;
811 			kl->l_schedflags = 0; /* XXX */
812 			kl->l_holdcnt = 0;
813 			kl->l_priority = l.l_priority;
814 			kl->l_usrpri = l.l_priority;
815 			kl->l_stat = l.l_stat;
816 			kl->l_wchan = PTRTOUINT64(l.l_wchan);
817 			if (l.l_wmesg)
818 				(void)kvm_read(kd, (u_long)l.l_wmesg,
819 				    kl->l_wmesg, (size_t)WMESGLEN);
820 			kl->l_cpuid = KI_NOCPU;
821 			laddr = (u_long)PTRTOUINT64(l.l_sibling.le_next);
822 		}
823 	}
824 
825 	*cnt = nlwps;
826 	return (kd->lwpbase);
827 }
828 
829 struct kinfo_proc *
830 kvm_getprocs(kvm_t *kd, int op, int arg, int *cnt)
831 {
832 	size_t size;
833 	int mib[4], st, nprocs;
834 
835 	if (ISALIVE(kd)) {
836 		size = 0;
837 		mib[0] = CTL_KERN;
838 		mib[1] = KERN_PROC;
839 		mib[2] = op;
840 		mib[3] = arg;
841 		st = sysctl(mib, 4, NULL, &size, NULL, (size_t)0);
842 		if (st == -1) {
843 			_kvm_syserr(kd, kd->program, "kvm_getprocs");
844 			return (NULL);
845 		}
846 		KVM_ALLOC(kd, procbase, size);
847 		st = sysctl(mib, 4, kd->procbase, &size, NULL, (size_t)0);
848 		if (st == -1) {
849 			_kvm_syserr(kd, kd->program, "kvm_getprocs");
850 			return (NULL);
851 		}
852 		if (size % sizeof(struct kinfo_proc) != 0) {
853 			_kvm_err(kd, kd->program,
854 			    "proc size mismatch (%lu total, %lu chunks)",
855 			    (u_long)size, (u_long)sizeof(struct kinfo_proc));
856 			return (NULL);
857 		}
858 		nprocs = (int) (size / sizeof(struct kinfo_proc));
859 	} else {
860 		struct nlist nl[4], *p;
861 
862 		(void)memset(nl, 0, sizeof(nl));
863 		nl[0].n_name = "_nprocs";
864 		nl[1].n_name = "_allproc";
865 		nl[2].n_name = "_zombproc";
866 		nl[3].n_name = NULL;
867 
868 		if (kvm_nlist(kd, nl) != 0) {
869 			for (p = nl; p->n_type != 0; ++p)
870 				continue;
871 			_kvm_err(kd, kd->program,
872 			    "%s: no such symbol", p->n_name);
873 			return (NULL);
874 		}
875 		if (KREAD(kd, nl[0].n_value, &nprocs)) {
876 			_kvm_err(kd, kd->program, "can't read nprocs");
877 			return (NULL);
878 		}
879 		size = nprocs * sizeof(*kd->procbase);
880 		KVM_ALLOC(kd, procbase, size);
881 		nprocs = kvm_deadprocs(kd, op, arg, nl[1].n_value,
882 		    nl[2].n_value, nprocs);
883 		if (nprocs < 0)
884 			return (NULL);
885 #ifdef notdef
886 		size = nprocs * sizeof(struct kinfo_proc);
887 		(void)realloc(kd->procbase, size);
888 #endif
889 	}
890 	*cnt = nprocs;
891 	return (kd->procbase);
892 }
893 
894 void *
895 _kvm_realloc(kvm_t *kd, void *p, size_t n)
896 {
897 	void *np = realloc(p, n);
898 
899 	if (np == NULL)
900 		_kvm_err(kd, kd->program, "out of memory");
901 	return (np);
902 }
903 
904 /*
905  * Read in an argument vector from the user address space of process p.
906  * addr if the user-space base address of narg null-terminated contiguous
907  * strings.  This is used to read in both the command arguments and
908  * environment strings.  Read at most maxcnt characters of strings.
909  */
910 static char **
911 kvm_argv(kvm_t *kd, const struct miniproc *p, u_long addr, int narg,
912 	 int maxcnt)
913 {
914 	char *np, *cp, *ep, *ap;
915 	u_long oaddr = (u_long)~0L;
916 	u_long len;
917 	size_t cc;
918 	char **argv;
919 
920 	/*
921 	 * Check that there aren't an unreasonable number of arguments,
922 	 * and that the address is in user space.
923 	 */
924 	if (narg > ARG_MAX || addr < kd->min_uva || addr >= kd->max_uva)
925 		return (NULL);
926 
927 	if (kd->argv == NULL) {
928 		/*
929 		 * Try to avoid reallocs.
930 		 */
931 		kd->argc = MAX(narg + 1, 32);
932 		kd->argv = _kvm_malloc(kd, kd->argc * sizeof(*kd->argv));
933 		if (kd->argv == NULL)
934 			return (NULL);
935 	} else if (narg + 1 > kd->argc) {
936 		kd->argc = MAX(2 * kd->argc, narg + 1);
937 		kd->argv = _kvm_realloc(kd, kd->argv, kd->argc *
938 		    sizeof(*kd->argv));
939 		if (kd->argv == NULL)
940 			return (NULL);
941 	}
942 	if (kd->argspc == NULL) {
943 		kd->argspc = _kvm_malloc(kd, (size_t)kd->nbpg);
944 		if (kd->argspc == NULL)
945 			return (NULL);
946 		kd->argspc_len = kd->nbpg;
947 	}
948 	if (kd->argbuf == NULL) {
949 		kd->argbuf = _kvm_malloc(kd, (size_t)kd->nbpg);
950 		if (kd->argbuf == NULL)
951 			return (NULL);
952 	}
953 	cc = sizeof(char *) * narg;
954 	if (kvm_ureadm(kd, p, addr, (void *)kd->argv, cc) != cc)
955 		return (NULL);
956 	ap = np = kd->argspc;
957 	argv = kd->argv;
958 	len = 0;
959 	/*
960 	 * Loop over pages, filling in the argument vector.
961 	 */
962 	while (argv < kd->argv + narg && *argv != NULL) {
963 		addr = (u_long)*argv & ~(kd->nbpg - 1);
964 		if (addr != oaddr) {
965 			if (kvm_ureadm(kd, p, addr, kd->argbuf,
966 			    (size_t)kd->nbpg) != kd->nbpg)
967 				return (NULL);
968 			oaddr = addr;
969 		}
970 		addr = (u_long)*argv & (kd->nbpg - 1);
971 		cp = kd->argbuf + (size_t)addr;
972 		cc = kd->nbpg - (size_t)addr;
973 		if (maxcnt > 0 && cc > (size_t)(maxcnt - len))
974 			cc = (size_t)(maxcnt - len);
975 		ep = memchr(cp, '\0', cc);
976 		if (ep != NULL)
977 			cc = ep - cp + 1;
978 		if (len + cc > kd->argspc_len) {
979 			ptrdiff_t off;
980 			char **pp;
981 			char *op = kd->argspc;
982 
983 			kd->argspc_len *= 2;
984 			kd->argspc = _kvm_realloc(kd, kd->argspc,
985 			    kd->argspc_len);
986 			if (kd->argspc == NULL)
987 				return (NULL);
988 			/*
989 			 * Adjust argv pointers in case realloc moved
990 			 * the string space.
991 			 */
992 			off = kd->argspc - op;
993 			for (pp = kd->argv; pp < argv; pp++)
994 				*pp += off;
995 			ap += off;
996 			np += off;
997 		}
998 		memcpy(np, cp, cc);
999 		np += cc;
1000 		len += cc;
1001 		if (ep != NULL) {
1002 			*argv++ = ap;
1003 			ap = np;
1004 		} else
1005 			*argv += cc;
1006 		if (maxcnt > 0 && len >= maxcnt) {
1007 			/*
1008 			 * We're stopping prematurely.  Terminate the
1009 			 * current string.
1010 			 */
1011 			if (ep == NULL) {
1012 				*np = '\0';
1013 				*argv++ = ap;
1014 			}
1015 			break;
1016 		}
1017 	}
1018 	/* Make sure argv is terminated. */
1019 	*argv = NULL;
1020 	return (kd->argv);
1021 }
1022 
1023 static void
1024 ps_str_a(struct ps_strings *p, u_long *addr, int *n)
1025 {
1026 
1027 	*addr = (u_long)p->ps_argvstr;
1028 	*n = p->ps_nargvstr;
1029 }
1030 
1031 static void
1032 ps_str_e(struct ps_strings *p, u_long *addr, int *n)
1033 {
1034 
1035 	*addr = (u_long)p->ps_envstr;
1036 	*n = p->ps_nenvstr;
1037 }
1038 
1039 /*
1040  * Determine if the proc indicated by p is still active.
1041  * This test is not 100% foolproof in theory, but chances of
1042  * being wrong are very low.
1043  */
1044 static int
1045 proc_verify(kvm_t *kd, u_long kernp, const struct miniproc *p)
1046 {
1047 	struct proc kernproc;
1048 
1049 	/*
1050 	 * Just read in the whole proc.  It's not that big relative
1051 	 * to the cost of the read system call.
1052 	 */
1053 	if (kvm_read(kd, kernp, &kernproc, sizeof(kernproc)) !=
1054 	    sizeof(kernproc))
1055 		return (0);
1056 	return (p->p_pid == kernproc.p_pid &&
1057 	    (kernproc.p_stat != SZOMB || p->p_stat == SZOMB));
1058 }
1059 
1060 static char **
1061 kvm_doargv(kvm_t *kd, const struct miniproc *p, int nchr,
1062 	   void (*info)(struct ps_strings *, u_long *, int *))
1063 {
1064 	char **ap;
1065 	u_long addr;
1066 	int cnt;
1067 	struct ps_strings arginfo;
1068 
1069 	/*
1070 	 * Pointers are stored at the top of the user stack.
1071 	 */
1072 	if (p->p_stat == SZOMB)
1073 		return (NULL);
1074 	cnt = (int)kvm_ureadm(kd, p, kd->usrstack - sizeof(arginfo),
1075 	    (void *)&arginfo, sizeof(arginfo));
1076 	if (cnt != sizeof(arginfo))
1077 		return (NULL);
1078 
1079 	(*info)(&arginfo, &addr, &cnt);
1080 	if (cnt == 0)
1081 		return (NULL);
1082 	ap = kvm_argv(kd, p, addr, cnt, nchr);
1083 	/*
1084 	 * For live kernels, make sure this process didn't go away.
1085 	 */
1086 	if (ap != NULL && ISALIVE(kd) &&
1087 	    !proc_verify(kd, (u_long)p->p_paddr, p))
1088 		ap = NULL;
1089 	return (ap);
1090 }
1091 
1092 /*
1093  * Get the command args.  This code is now machine independent.
1094  */
1095 char **
1096 kvm_getargv(kvm_t *kd, const struct kinfo_proc *kp, int nchr)
1097 {
1098 	struct miniproc p;
1099 
1100 	KPTOMINI(kp, &p);
1101 	return (kvm_doargv(kd, &p, nchr, ps_str_a));
1102 }
1103 
1104 char **
1105 kvm_getenvv(kvm_t *kd, const struct kinfo_proc *kp, int nchr)
1106 {
1107 	struct miniproc p;
1108 
1109 	KPTOMINI(kp, &p);
1110 	return (kvm_doargv(kd, &p, nchr, ps_str_e));
1111 }
1112 
1113 static char **
1114 kvm_doargv2(kvm_t *kd, pid_t pid, int type, int nchr)
1115 {
1116 	size_t bufs;
1117 	int narg, mib[4];
1118 	size_t newargspc_len;
1119 	char **ap, *bp, *endp;
1120 
1121 	/*
1122 	 * Check that there aren't an unreasonable number of arguments.
1123 	 */
1124 	if (nchr > ARG_MAX)
1125 		return (NULL);
1126 
1127 	if (nchr == 0)
1128 		nchr = ARG_MAX;
1129 
1130 	/* Get number of strings in argv */
1131 	mib[0] = CTL_KERN;
1132 	mib[1] = KERN_PROC_ARGS;
1133 	mib[2] = pid;
1134 	mib[3] = type == KERN_PROC_ARGV ? KERN_PROC_NARGV : KERN_PROC_NENV;
1135 	bufs = sizeof(narg);
1136 	if (sysctl(mib, 4, &narg, &bufs, NULL, (size_t)0) == -1)
1137 		return (NULL);
1138 
1139 	if (kd->argv == NULL) {
1140 		/*
1141 		 * Try to avoid reallocs.
1142 		 */
1143 		kd->argc = MAX(narg + 1, 32);
1144 		kd->argv = _kvm_malloc(kd, kd->argc * sizeof(*kd->argv));
1145 		if (kd->argv == NULL)
1146 			return (NULL);
1147 	} else if (narg + 1 > kd->argc) {
1148 		kd->argc = MAX(2 * kd->argc, narg + 1);
1149 		kd->argv = _kvm_realloc(kd, kd->argv, kd->argc *
1150 		    sizeof(*kd->argv));
1151 		if (kd->argv == NULL)
1152 			return (NULL);
1153 	}
1154 
1155 	newargspc_len = MIN(nchr, ARG_MAX);
1156 	KVM_ALLOC(kd, argspc, newargspc_len);
1157 	memset(kd->argspc, 0, (size_t)kd->argspc_len);	/* XXX necessary? */
1158 
1159 	mib[0] = CTL_KERN;
1160 	mib[1] = KERN_PROC_ARGS;
1161 	mib[2] = pid;
1162 	mib[3] = type;
1163 	bufs = kd->argspc_len;
1164 	if (sysctl(mib, 4, kd->argspc, &bufs, NULL, (size_t)0) == -1)
1165 		return (NULL);
1166 
1167 	bp = kd->argspc;
1168 	bp[kd->argspc_len-1] = '\0';	/* make sure the string ends with nul */
1169 	ap = kd->argv;
1170 	endp = bp + MIN(nchr, bufs);
1171 
1172 	while (bp < endp) {
1173 		*ap++ = bp;
1174 		/*
1175 		 * XXX: don't need following anymore, or stick check
1176 		 * for max argc in above while loop?
1177 		 */
1178 		if (ap >= kd->argv + kd->argc) {
1179 			kd->argc *= 2;
1180 			kd->argv = _kvm_realloc(kd, kd->argv,
1181 			    kd->argc * sizeof(*kd->argv));
1182 			ap = kd->argv;
1183 		}
1184 		bp += strlen(bp) + 1;
1185 	}
1186 	*ap = NULL;
1187 
1188 	return (kd->argv);
1189 }
1190 
1191 char **
1192 kvm_getargv2(kvm_t *kd, const struct kinfo_proc2 *kp, int nchr)
1193 {
1194 
1195 	return (kvm_doargv2(kd, kp->p_pid, KERN_PROC_ARGV, nchr));
1196 }
1197 
1198 char **
1199 kvm_getenvv2(kvm_t *kd, const struct kinfo_proc2 *kp, int nchr)
1200 {
1201 
1202 	return (kvm_doargv2(kd, kp->p_pid, KERN_PROC_ENV, nchr));
1203 }
1204 
1205 /*
1206  * Read from user space.  The user context is given by p.
1207  */
1208 static ssize_t
1209 kvm_ureadm(kvm_t *kd, const struct miniproc *p, u_long uva,
1210 	   char *buf, size_t len)
1211 {
1212 	char *cp;
1213 
1214 	cp = buf;
1215 	while (len > 0) {
1216 		size_t cc;
1217 		char *dp;
1218 		u_long cnt;
1219 
1220 		dp = _kvm_ureadm(kd, p, uva, &cnt);
1221 		if (dp == NULL) {
1222 			_kvm_err(kd, 0, "invalid address (%lx)", uva);
1223 			return (0);
1224 		}
1225 		cc = (size_t)MIN(cnt, len);
1226 		memcpy(cp, dp, cc);
1227 		cp += cc;
1228 		uva += cc;
1229 		len -= cc;
1230 	}
1231 	return (ssize_t)(cp - buf);
1232 }
1233 
1234 ssize_t
1235 kvm_uread(kvm_t *kd, const struct proc *p, u_long uva, char *buf, size_t len)
1236 {
1237 	struct miniproc mp;
1238 
1239 	PTOMINI(p, &mp);
1240 	return (kvm_ureadm(kd, &mp, uva, buf, len));
1241 }
1242