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kvm_proc.c revision 1.88
      1 /*	$NetBSD: kvm_proc.c,v 1.88 2010/11/12 04:52:08 uebayasi 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 1.88 2010/11/12 04:52:08 uebayasi 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/user.h>
     83 #include <sys/lwp.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 	uint8_t cr_pad[CACHE_LINE_SIZE - sizeof(u_int)];
    163 	uid_t cr_uid;			/* user id */
    164 	uid_t cr_euid;			/* effective user id */
    165 	uid_t cr_svuid;			/* saved effective user id */
    166 	gid_t cr_gid;			/* group id */
    167 	gid_t cr_egid;			/* effective group id */
    168 	gid_t cr_svgid;			/* saved effective group id */
    169 	u_int cr_ngroups;		/* number of groups */
    170 	gid_t cr_groups[NGROUPS];	/* group memberships */
    171 	specificdata_reference cr_sd;	/* specific data */
    172 };
    173 
    174 /* XXX: What uses these two functions? */
    175 char		*_kvm_uread(kvm_t *, const struct proc *, u_long, u_long *);
    176 ssize_t		kvm_uread(kvm_t *, const struct proc *, u_long, char *,
    177 		    size_t);
    178 
    179 static char	*_kvm_ureadm(kvm_t *, const struct miniproc *, u_long,
    180 		    u_long *);
    181 static ssize_t	kvm_ureadm(kvm_t *, const struct miniproc *, u_long,
    182 		    char *, size_t);
    183 
    184 static char	**kvm_argv(kvm_t *, const struct miniproc *, u_long, int, int);
    185 static int	kvm_deadprocs(kvm_t *, int, int, u_long, u_long, int);
    186 static char	**kvm_doargv(kvm_t *, const struct miniproc *, int,
    187 		    void (*)(struct ps_strings *, u_long *, int *));
    188 static char	**kvm_doargv2(kvm_t *, pid_t, int, int);
    189 static int	kvm_proclist(kvm_t *, int, int, struct proc *,
    190 		    struct kinfo_proc *, int);
    191 static int	proc_verify(kvm_t *, u_long, const struct miniproc *);
    192 static void	ps_str_a(struct ps_strings *, u_long *, int *);
    193 static void	ps_str_e(struct ps_strings *, u_long *, int *);
    194 
    195 
    196 static char *
    197 _kvm_ureadm(kvm_t *kd, const struct miniproc *p, u_long va, u_long *cnt)
    198 {
    199 	u_long addr, head;
    200 	u_long offset;
    201 	struct vm_map_entry vme;
    202 	struct vm_amap amap;
    203 	struct vm_anon *anonp, anon;
    204 	struct vm_page pg;
    205 	u_long slot;
    206 
    207 	if (kd->swapspc == NULL) {
    208 		kd->swapspc = _kvm_malloc(kd, (size_t)kd->nbpg);
    209 		if (kd->swapspc == NULL)
    210 			return (NULL);
    211 	}
    212 
    213 	/*
    214 	 * Look through the address map for the memory object
    215 	 * that corresponds to the given virtual address.
    216 	 * The header just has the entire valid range.
    217 	 */
    218 	head = (u_long)&p->p_vmspace->vm_map.header;
    219 	addr = head;
    220 	for (;;) {
    221 		if (KREAD(kd, addr, &vme))
    222 			return (NULL);
    223 
    224 		if (va >= vme.start && va < vme.end &&
    225 		    vme.aref.ar_amap != NULL)
    226 			break;
    227 
    228 		addr = (u_long)vme.next;
    229 		if (addr == head)
    230 			return (NULL);
    231 	}
    232 
    233 	/*
    234 	 * we found the map entry, now to find the object...
    235 	 */
    236 	if (vme.aref.ar_amap == NULL)
    237 		return (NULL);
    238 
    239 	addr = (u_long)vme.aref.ar_amap;
    240 	if (KREAD(kd, addr, &amap))
    241 		return (NULL);
    242 
    243 	offset = va - vme.start;
    244 	slot = offset / kd->nbpg + vme.aref.ar_pageoff;
    245 	/* sanity-check slot number */
    246 	if (slot > amap.am_nslot)
    247 		return (NULL);
    248 
    249 	addr = (u_long)amap.am_anon + (offset / kd->nbpg) * sizeof(anonp);
    250 	if (KREAD(kd, addr, &anonp))
    251 		return (NULL);
    252 
    253 	addr = (u_long)anonp;
    254 	if (KREAD(kd, addr, &anon))
    255 		return (NULL);
    256 
    257 	addr = (u_long)anon.an_page;
    258 	if (addr) {
    259 		if (KREAD(kd, addr, &pg))
    260 			return (NULL);
    261 
    262 		if (_kvm_pread(kd, kd->pmfd, kd->swapspc, (size_t)kd->nbpg,
    263 		    (off_t)pg.phys_addr) != kd->nbpg)
    264 			return (NULL);
    265 	} else {
    266 		if (kd->swfd < 0 ||
    267 		    _kvm_pread(kd, kd->swfd, kd->swapspc, (size_t)kd->nbpg,
    268 		    (off_t)(anon.an_swslot * kd->nbpg)) != kd->nbpg)
    269 			return (NULL);
    270 	}
    271 
    272 	/* Found the page. */
    273 	offset %= kd->nbpg;
    274 	*cnt = kd->nbpg - offset;
    275 	return (&kd->swapspc[(size_t)offset]);
    276 }
    277 
    278 char *
    279 _kvm_uread(kvm_t *kd, const struct proc *p, u_long va, u_long *cnt)
    280 {
    281 	struct miniproc mp;
    282 
    283 	PTOMINI(p, &mp);
    284 	return (_kvm_ureadm(kd, &mp, va, cnt));
    285 }
    286 
    287 /*
    288  * Convert credentials located in kernel space address 'cred' and store
    289  * them in the appropriate members of 'eproc'.
    290  */
    291 static int
    292 _kvm_convertcred(kvm_t *kd, u_long cred, struct eproc *eproc)
    293 {
    294 	struct kvm_kauth_cred kauthcred;
    295 	struct ki_pcred *pc = &eproc->e_pcred;
    296 	struct ki_ucred *uc = &eproc->e_ucred;
    297 
    298 	if (KREAD(kd, cred, &kauthcred) != 0)
    299 		return (-1);
    300 
    301 	/* inlined version of kauth_cred_to_pcred, see kauth(9). */
    302 	pc->p_ruid = kauthcred.cr_uid;
    303 	pc->p_svuid = kauthcred.cr_svuid;
    304 	pc->p_rgid = kauthcred.cr_gid;
    305 	pc->p_svgid = kauthcred.cr_svgid;
    306 	pc->p_refcnt = kauthcred.cr_refcnt;
    307 	pc->p_pad = NULL;
    308 
    309 	/* inlined version of kauth_cred_to_ucred(), see kauth(9). */
    310 	uc->cr_ref = kauthcred.cr_refcnt;
    311 	uc->cr_uid = kauthcred.cr_euid;
    312 	uc->cr_gid = kauthcred.cr_egid;
    313 	uc->cr_ngroups = (uint32_t)MIN(kauthcred.cr_ngroups,
    314 	    sizeof(uc->cr_groups) / sizeof(uc->cr_groups[0]));
    315 	memcpy(uc->cr_groups, kauthcred.cr_groups,
    316 	    uc->cr_ngroups * sizeof(uc->cr_groups[0]));
    317 
    318 	return (0);
    319 }
    320 
    321 /*
    322  * Read proc's from memory file into buffer bp, which has space to hold
    323  * at most maxcnt procs.
    324  */
    325 static int
    326 kvm_proclist(kvm_t *kd, int what, int arg, struct proc *p,
    327 	     struct kinfo_proc *bp, int maxcnt)
    328 {
    329 	int cnt = 0;
    330 	int nlwps;
    331 	struct kinfo_lwp *kl;
    332 	struct eproc eproc;
    333 	struct pgrp pgrp;
    334 	struct session sess;
    335 	struct tty tty;
    336 	struct proc proc;
    337 
    338 	for (; cnt < maxcnt && p != NULL; p = proc.p_list.le_next) {
    339 		if (KREAD(kd, (u_long)p, &proc)) {
    340 			_kvm_err(kd, kd->program, "can't read proc at %p", p);
    341 			return (-1);
    342 		}
    343 		if (_kvm_convertcred(kd, (u_long)proc.p_cred, &eproc) != 0) {
    344 			_kvm_err(kd, kd->program,
    345 			    "can't read proc credentials at %p", p);
    346 			return (-1);
    347 		}
    348 
    349 		switch (what) {
    350 
    351 		case KERN_PROC_PID:
    352 			if (proc.p_pid != (pid_t)arg)
    353 				continue;
    354 			break;
    355 
    356 		case KERN_PROC_UID:
    357 			if (eproc.e_ucred.cr_uid != (uid_t)arg)
    358 				continue;
    359 			break;
    360 
    361 		case KERN_PROC_RUID:
    362 			if (eproc.e_pcred.p_ruid != (uid_t)arg)
    363 				continue;
    364 			break;
    365 		}
    366 		/*
    367 		 * We're going to add another proc to the set.  If this
    368 		 * will overflow the buffer, assume the reason is because
    369 		 * nprocs (or the proc list) is corrupt and declare an error.
    370 		 */
    371 		if (cnt >= maxcnt) {
    372 			_kvm_err(kd, kd->program, "nprocs corrupt");
    373 			return (-1);
    374 		}
    375 		/*
    376 		 * gather eproc
    377 		 */
    378 		eproc.e_paddr = p;
    379 		if (KREAD(kd, (u_long)proc.p_pgrp, &pgrp)) {
    380 			_kvm_err(kd, kd->program, "can't read pgrp at %p",
    381 			    proc.p_pgrp);
    382 			return (-1);
    383 		}
    384 		eproc.e_sess = pgrp.pg_session;
    385 		eproc.e_pgid = pgrp.pg_id;
    386 		eproc.e_jobc = pgrp.pg_jobc;
    387 		if (KREAD(kd, (u_long)pgrp.pg_session, &sess)) {
    388 			_kvm_err(kd, kd->program, "can't read session at %p",
    389 			    pgrp.pg_session);
    390 			return (-1);
    391 		}
    392 		if ((proc.p_lflag & PL_CONTROLT) && sess.s_ttyp != NULL) {
    393 			if (KREAD(kd, (u_long)sess.s_ttyp, &tty)) {
    394 				_kvm_err(kd, kd->program,
    395 				    "can't read tty at %p", sess.s_ttyp);
    396 				return (-1);
    397 			}
    398 			eproc.e_tdev = (uint32_t)tty.t_dev;
    399 			eproc.e_tsess = tty.t_session;
    400 			if (tty.t_pgrp != NULL) {
    401 				if (KREAD(kd, (u_long)tty.t_pgrp, &pgrp)) {
    402 					_kvm_err(kd, kd->program,
    403 					    "can't read tpgrp at %p",
    404 					    tty.t_pgrp);
    405 					return (-1);
    406 				}
    407 				eproc.e_tpgid = pgrp.pg_id;
    408 			} else
    409 				eproc.e_tpgid = -1;
    410 		} else
    411 			eproc.e_tdev = (uint32_t)NODEV;
    412 		eproc.e_flag = sess.s_ttyvp ? EPROC_CTTY : 0;
    413 		eproc.e_sid = sess.s_sid;
    414 		if (sess.s_leader == p)
    415 			eproc.e_flag |= EPROC_SLEADER;
    416 		/*
    417 		 * Fill in the old-style proc.p_wmesg by copying the wmesg
    418 		 * from the first available LWP.
    419 		 */
    420 		kl = kvm_getlwps(kd, proc.p_pid,
    421 		    (u_long)PTRTOUINT64(eproc.e_paddr),
    422 		    sizeof(struct kinfo_lwp), &nlwps);
    423 		if (kl) {
    424 			if (nlwps > 0) {
    425 				strcpy(eproc.e_wmesg, kl[0].l_wmesg);
    426 			}
    427 		}
    428 		(void)kvm_read(kd, (u_long)proc.p_vmspace, &eproc.e_vm,
    429 		    sizeof(eproc.e_vm));
    430 
    431 		eproc.e_xsize = eproc.e_xrssize = 0;
    432 		eproc.e_xccount = eproc.e_xswrss = 0;
    433 
    434 		switch (what) {
    435 
    436 		case KERN_PROC_PGRP:
    437 			if (eproc.e_pgid != (pid_t)arg)
    438 				continue;
    439 			break;
    440 
    441 		case KERN_PROC_TTY:
    442 			if ((proc.p_lflag & PL_CONTROLT) == 0 ||
    443 			    eproc.e_tdev != (dev_t)arg)
    444 				continue;
    445 			break;
    446 		}
    447 		memcpy(&bp->kp_proc, &proc, sizeof(proc));
    448 		memcpy(&bp->kp_eproc, &eproc, sizeof(eproc));
    449 		++bp;
    450 		++cnt;
    451 	}
    452 	return (cnt);
    453 }
    454 
    455 /*
    456  * Build proc info array by reading in proc list from a crash dump.
    457  * Return number of procs read.  maxcnt is the max we will read.
    458  */
    459 static int
    460 kvm_deadprocs(kvm_t *kd, int what, int arg, u_long a_allproc,
    461 	      u_long a_zombproc, int maxcnt)
    462 {
    463 	struct kinfo_proc *bp = kd->procbase;
    464 	int acnt, zcnt;
    465 	struct proc *p;
    466 
    467 	if (KREAD(kd, a_allproc, &p)) {
    468 		_kvm_err(kd, kd->program, "cannot read allproc");
    469 		return (-1);
    470 	}
    471 	acnt = kvm_proclist(kd, what, arg, p, bp, maxcnt);
    472 	if (acnt < 0)
    473 		return (acnt);
    474 
    475 	if (KREAD(kd, a_zombproc, &p)) {
    476 		_kvm_err(kd, kd->program, "cannot read zombproc");
    477 		return (-1);
    478 	}
    479 	zcnt = kvm_proclist(kd, what, arg, p, bp + acnt,
    480 	    maxcnt - acnt);
    481 	if (zcnt < 0)
    482 		zcnt = 0;
    483 
    484 	return (acnt + zcnt);
    485 }
    486 
    487 struct kinfo_proc2 *
    488 kvm_getproc2(kvm_t *kd, int op, int arg, size_t esize, int *cnt)
    489 {
    490 	size_t size;
    491 	int mib[6], st, nprocs;
    492 	struct pstats pstats;
    493 
    494 	if (ISSYSCTL(kd)) {
    495 		size = 0;
    496 		mib[0] = CTL_KERN;
    497 		mib[1] = KERN_PROC2;
    498 		mib[2] = op;
    499 		mib[3] = arg;
    500 		mib[4] = (int)esize;
    501 again:
    502 		mib[5] = 0;
    503 		st = sysctl(mib, 6, NULL, &size, NULL, (size_t)0);
    504 		if (st == -1) {
    505 			_kvm_syserr(kd, kd->program, "kvm_getproc2");
    506 			return (NULL);
    507 		}
    508 
    509 		mib[5] = (int) (size / esize);
    510 		KVM_ALLOC(kd, procbase2, size);
    511 		st = sysctl(mib, 6, kd->procbase2, &size, NULL, (size_t)0);
    512 		if (st == -1) {
    513 			if (errno == ENOMEM) {
    514 				goto again;
    515 			}
    516 			_kvm_syserr(kd, kd->program, "kvm_getproc2");
    517 			return (NULL);
    518 		}
    519 		nprocs = (int) (size / esize);
    520 	} else {
    521 		char *kp2c;
    522 		struct kinfo_proc *kp;
    523 		struct kinfo_proc2 kp2, *kp2p;
    524 		struct kinfo_lwp *kl;
    525 		int i, nlwps;
    526 
    527 		kp = kvm_getprocs(kd, op, arg, &nprocs);
    528 		if (kp == NULL)
    529 			return (NULL);
    530 
    531 		size = nprocs * esize;
    532 		KVM_ALLOC(kd, procbase2, size);
    533 		kp2c = (char *)(void *)kd->procbase2;
    534 		kp2p = &kp2;
    535 		for (i = 0; i < nprocs; i++, kp++) {
    536 			struct timeval tv;
    537 
    538 			kl = kvm_getlwps(kd, kp->kp_proc.p_pid,
    539 			    (u_long)PTRTOUINT64(kp->kp_eproc.e_paddr),
    540 			    sizeof(struct kinfo_lwp), &nlwps);
    541 
    542 			if (kl == NULL) {
    543 				_kvm_syserr(kd, NULL,
    544 					"kvm_getlwps() failed on process %u\n",
    545 					kp->kp_proc.p_pid);
    546 				if (nlwps == 0)
    547 					return NULL;
    548 				else
    549 					continue;
    550 			}
    551 
    552 			/* We use kl[0] as the "representative" LWP */
    553 			memset(kp2p, 0, sizeof(kp2));
    554 			kp2p->p_forw = kl[0].l_forw;
    555 			kp2p->p_back = kl[0].l_back;
    556 			kp2p->p_paddr = PTRTOUINT64(kp->kp_eproc.e_paddr);
    557 			kp2p->p_addr = kl[0].l_addr;
    558 			kp2p->p_fd = PTRTOUINT64(kp->kp_proc.p_fd);
    559 			kp2p->p_cwdi = PTRTOUINT64(kp->kp_proc.p_cwdi);
    560 			kp2p->p_stats = PTRTOUINT64(kp->kp_proc.p_stats);
    561 			kp2p->p_limit = PTRTOUINT64(kp->kp_proc.p_limit);
    562 			kp2p->p_vmspace = PTRTOUINT64(kp->kp_proc.p_vmspace);
    563 			kp2p->p_sigacts = PTRTOUINT64(kp->kp_proc.p_sigacts);
    564 			kp2p->p_sess = PTRTOUINT64(kp->kp_eproc.e_sess);
    565 			kp2p->p_tsess = 0;
    566 #if 1 /* XXX: dsl - p_ru was only ever non-zero for zombies */
    567 			kp2p->p_ru = 0;
    568 #else
    569 			kp2p->p_ru = PTRTOUINT64(pstats.p_ru);
    570 #endif
    571 
    572 			kp2p->p_eflag = 0;
    573 			kp2p->p_exitsig = kp->kp_proc.p_exitsig;
    574 			kp2p->p_flag = kp->kp_proc.p_flag;
    575 
    576 			kp2p->p_pid = kp->kp_proc.p_pid;
    577 
    578 			kp2p->p_ppid = kp->kp_eproc.e_ppid;
    579 			kp2p->p_sid = kp->kp_eproc.e_sid;
    580 			kp2p->p__pgid = kp->kp_eproc.e_pgid;
    581 
    582 			kp2p->p_tpgid = -1 /* XXX NO_PGID! */;
    583 
    584 			kp2p->p_uid = kp->kp_eproc.e_ucred.cr_uid;
    585 			kp2p->p_ruid = kp->kp_eproc.e_pcred.p_ruid;
    586 			kp2p->p_svuid = kp->kp_eproc.e_pcred.p_svuid;
    587 			kp2p->p_gid = kp->kp_eproc.e_ucred.cr_gid;
    588 			kp2p->p_rgid = kp->kp_eproc.e_pcred.p_rgid;
    589 			kp2p->p_svgid = kp->kp_eproc.e_pcred.p_svgid;
    590 
    591 			/*CONSTCOND*/
    592 			memcpy(kp2p->p_groups, kp->kp_eproc.e_ucred.cr_groups,
    593 			    MIN(sizeof(kp2p->p_groups),
    594 			    sizeof(kp->kp_eproc.e_ucred.cr_groups)));
    595 			kp2p->p_ngroups = kp->kp_eproc.e_ucred.cr_ngroups;
    596 
    597 			kp2p->p_jobc = kp->kp_eproc.e_jobc;
    598 			kp2p->p_tdev = kp->kp_eproc.e_tdev;
    599 			kp2p->p_tpgid = kp->kp_eproc.e_tpgid;
    600 			kp2p->p_tsess = PTRTOUINT64(kp->kp_eproc.e_tsess);
    601 
    602 			kp2p->p_estcpu = 0;
    603 			bintime2timeval(&kp->kp_proc.p_rtime, &tv);
    604 			kp2p->p_rtime_sec = (uint32_t)tv.tv_sec;
    605 			kp2p->p_rtime_usec = (uint32_t)tv.tv_usec;
    606 			kp2p->p_cpticks = kl[0].l_cpticks;
    607 			kp2p->p_pctcpu = kp->kp_proc.p_pctcpu;
    608 			kp2p->p_swtime = kl[0].l_swtime;
    609 			kp2p->p_slptime = kl[0].l_slptime;
    610 #if 0 /* XXX thorpej */
    611 			kp2p->p_schedflags = kp->kp_proc.p_schedflags;
    612 #else
    613 			kp2p->p_schedflags = 0;
    614 #endif
    615 
    616 			kp2p->p_uticks = kp->kp_proc.p_uticks;
    617 			kp2p->p_sticks = kp->kp_proc.p_sticks;
    618 			kp2p->p_iticks = kp->kp_proc.p_iticks;
    619 
    620 			kp2p->p_tracep = PTRTOUINT64(kp->kp_proc.p_tracep);
    621 			kp2p->p_traceflag = kp->kp_proc.p_traceflag;
    622 
    623 			kp2p->p_holdcnt = kl[0].l_holdcnt;
    624 
    625 			memcpy(&kp2p->p_siglist,
    626 			    &kp->kp_proc.p_sigpend.sp_set,
    627 			    sizeof(ki_sigset_t));
    628 			memset(&kp2p->p_sigmask, 0,
    629 			    sizeof(ki_sigset_t));
    630 			memcpy(&kp2p->p_sigignore,
    631 			    &kp->kp_proc.p_sigctx.ps_sigignore,
    632 			    sizeof(ki_sigset_t));
    633 			memcpy(&kp2p->p_sigcatch,
    634 			    &kp->kp_proc.p_sigctx.ps_sigcatch,
    635 			    sizeof(ki_sigset_t));
    636 
    637 			kp2p->p_stat = kl[0].l_stat;
    638 			kp2p->p_priority = kl[0].l_priority;
    639 			kp2p->p_usrpri = kl[0].l_priority;
    640 			kp2p->p_nice = kp->kp_proc.p_nice;
    641 
    642 			kp2p->p_xstat = kp->kp_proc.p_xstat;
    643 			kp2p->p_acflag = kp->kp_proc.p_acflag;
    644 
    645 			/*CONSTCOND*/
    646 			strncpy(kp2p->p_comm, kp->kp_proc.p_comm,
    647 			    MIN(sizeof(kp2p->p_comm),
    648 			    sizeof(kp->kp_proc.p_comm)));
    649 
    650 			strncpy(kp2p->p_wmesg, kp->kp_eproc.e_wmesg,
    651 			    sizeof(kp2p->p_wmesg));
    652 			kp2p->p_wchan = kl[0].l_wchan;
    653 			strncpy(kp2p->p_login, kp->kp_eproc.e_login,
    654 			    sizeof(kp2p->p_login));
    655 
    656 			kp2p->p_vm_rssize = kp->kp_eproc.e_xrssize;
    657 			kp2p->p_vm_tsize = kp->kp_eproc.e_vm.vm_tsize;
    658 			kp2p->p_vm_dsize = kp->kp_eproc.e_vm.vm_dsize;
    659 			kp2p->p_vm_ssize = kp->kp_eproc.e_vm.vm_ssize;
    660 			kp2p->p_vm_vsize = kp->kp_eproc.e_vm.vm_map.size;
    661 			/* Adjust mapped size */
    662 			kp2p->p_vm_msize =
    663 			    (kp->kp_eproc.e_vm.vm_map.size / kd->nbpg) -
    664 			    kp->kp_eproc.e_vm.vm_issize +
    665 			    kp->kp_eproc.e_vm.vm_ssize;
    666 
    667 			kp2p->p_eflag = (int32_t)kp->kp_eproc.e_flag;
    668 
    669 			kp2p->p_realflag = kp->kp_proc.p_flag;
    670 			kp2p->p_nlwps = kp->kp_proc.p_nlwps;
    671 			kp2p->p_nrlwps = kp->kp_proc.p_nrlwps;
    672 			kp2p->p_realstat = kp->kp_proc.p_stat;
    673 
    674 			if (P_ZOMBIE(&kp->kp_proc) ||
    675 			    kp->kp_proc.p_stats == NULL ||
    676 			    KREAD(kd, (u_long)kp->kp_proc.p_stats, &pstats)) {
    677 				kp2p->p_uvalid = 0;
    678 			} else {
    679 				kp2p->p_uvalid = 1;
    680 
    681 				kp2p->p_ustart_sec = (u_int32_t)
    682 				    pstats.p_start.tv_sec;
    683 				kp2p->p_ustart_usec = (u_int32_t)
    684 				    pstats.p_start.tv_usec;
    685 
    686 				kp2p->p_uutime_sec = (u_int32_t)
    687 				    pstats.p_ru.ru_utime.tv_sec;
    688 				kp2p->p_uutime_usec = (u_int32_t)
    689 				    pstats.p_ru.ru_utime.tv_usec;
    690 				kp2p->p_ustime_sec = (u_int32_t)
    691 				    pstats.p_ru.ru_stime.tv_sec;
    692 				kp2p->p_ustime_usec = (u_int32_t)
    693 				    pstats.p_ru.ru_stime.tv_usec;
    694 
    695 				kp2p->p_uru_maxrss = pstats.p_ru.ru_maxrss;
    696 				kp2p->p_uru_ixrss = pstats.p_ru.ru_ixrss;
    697 				kp2p->p_uru_idrss = pstats.p_ru.ru_idrss;
    698 				kp2p->p_uru_isrss = pstats.p_ru.ru_isrss;
    699 				kp2p->p_uru_minflt = pstats.p_ru.ru_minflt;
    700 				kp2p->p_uru_majflt = pstats.p_ru.ru_majflt;
    701 				kp2p->p_uru_nswap = pstats.p_ru.ru_nswap;
    702 				kp2p->p_uru_inblock = pstats.p_ru.ru_inblock;
    703 				kp2p->p_uru_oublock = pstats.p_ru.ru_oublock;
    704 				kp2p->p_uru_msgsnd = pstats.p_ru.ru_msgsnd;
    705 				kp2p->p_uru_msgrcv = pstats.p_ru.ru_msgrcv;
    706 				kp2p->p_uru_nsignals = pstats.p_ru.ru_nsignals;
    707 				kp2p->p_uru_nvcsw = pstats.p_ru.ru_nvcsw;
    708 				kp2p->p_uru_nivcsw = pstats.p_ru.ru_nivcsw;
    709 
    710 				kp2p->p_uctime_sec = (u_int32_t)
    711 				    (pstats.p_cru.ru_utime.tv_sec +
    712 				    pstats.p_cru.ru_stime.tv_sec);
    713 				kp2p->p_uctime_usec = (u_int32_t)
    714 				    (pstats.p_cru.ru_utime.tv_usec +
    715 				    pstats.p_cru.ru_stime.tv_usec);
    716 			}
    717 
    718 			memcpy(kp2c, &kp2, esize);
    719 			kp2c += esize;
    720 		}
    721 	}
    722 	*cnt = nprocs;
    723 	return (kd->procbase2);
    724 }
    725 
    726 struct kinfo_lwp *
    727 kvm_getlwps(kvm_t *kd, int pid, u_long paddr, size_t esize, int *cnt)
    728 {
    729 	size_t size;
    730 	int mib[5], nlwps;
    731 	ssize_t st;
    732 	struct kinfo_lwp *kl;
    733 
    734 	if (ISSYSCTL(kd)) {
    735 		size = 0;
    736 		mib[0] = CTL_KERN;
    737 		mib[1] = KERN_LWP;
    738 		mib[2] = pid;
    739 		mib[3] = (int)esize;
    740 		mib[4] = 0;
    741 again:
    742 		st = sysctl(mib, 5, NULL, &size, NULL, (size_t)0);
    743 		if (st == -1) {
    744 			switch (errno) {
    745 			case ESRCH: /* Treat this as a soft error; see kvm.c */
    746 				_kvm_syserr(kd, NULL, "kvm_getlwps");
    747 				return NULL;
    748 			default:
    749 				_kvm_syserr(kd, kd->program, "kvm_getlwps");
    750 				return NULL;
    751 			}
    752 		}
    753 		mib[4] = (int) (size / esize);
    754 		KVM_ALLOC(kd, lwpbase, size);
    755 		st = sysctl(mib, 5, kd->lwpbase, &size, NULL, (size_t)0);
    756 		if (st == -1) {
    757 			switch (errno) {
    758 			case ESRCH: /* Treat this as a soft error; see kvm.c */
    759 				_kvm_syserr(kd, NULL, "kvm_getlwps");
    760 				return NULL;
    761 			case ENOMEM:
    762 				goto again;
    763 			default:
    764 				_kvm_syserr(kd, kd->program, "kvm_getlwps");
    765 				return NULL;
    766 			}
    767 		}
    768 		nlwps = (int) (size / esize);
    769 	} else {
    770 		/* grovel through the memory image */
    771 		struct proc p;
    772 		struct lwp l;
    773 		u_long laddr;
    774 		void *back;
    775 		int i;
    776 
    777 		st = kvm_read(kd, paddr, &p, sizeof(p));
    778 		if (st == -1) {
    779 			_kvm_syserr(kd, kd->program, "kvm_getlwps");
    780 			return (NULL);
    781 		}
    782 
    783 		nlwps = p.p_nlwps;
    784 		size = nlwps * sizeof(*kd->lwpbase);
    785 		KVM_ALLOC(kd, lwpbase, size);
    786 		laddr = (u_long)PTRTOUINT64(p.p_lwps.lh_first);
    787 		for (i = 0; (i < nlwps) && (laddr != 0); i++) {
    788 			st = kvm_read(kd, laddr, &l, sizeof(l));
    789 			if (st == -1) {
    790 				_kvm_syserr(kd, kd->program, "kvm_getlwps");
    791 				return (NULL);
    792 			}
    793 			kl = &kd->lwpbase[i];
    794 			kl->l_laddr = laddr;
    795 			kl->l_forw = PTRTOUINT64(l.l_runq.tqe_next);
    796 			laddr = (u_long)PTRTOUINT64(l.l_runq.tqe_prev);
    797 			st = kvm_read(kd, laddr, &back, sizeof(back));
    798 			if (st == -1) {
    799 				_kvm_syserr(kd, kd->program, "kvm_getlwps");
    800 				return (NULL);
    801 			}
    802 			kl->l_back = PTRTOUINT64(back);
    803 			kl->l_addr = PTRTOUINT64(l.l_addr);
    804 			kl->l_lid = l.l_lid;
    805 			kl->l_flag = l.l_flag;
    806 			kl->l_swtime = l.l_swtime;
    807 			kl->l_slptime = l.l_slptime;
    808 			kl->l_schedflags = 0; /* XXX */
    809 			kl->l_holdcnt = 0;
    810 			kl->l_priority = l.l_priority;
    811 			kl->l_usrpri = l.l_priority;
    812 			kl->l_stat = l.l_stat;
    813 			kl->l_wchan = PTRTOUINT64(l.l_wchan);
    814 			if (l.l_wmesg)
    815 				(void)kvm_read(kd, (u_long)l.l_wmesg,
    816 				    kl->l_wmesg, (size_t)WMESGLEN);
    817 			kl->l_cpuid = KI_NOCPU;
    818 			laddr = (u_long)PTRTOUINT64(l.l_sibling.le_next);
    819 		}
    820 	}
    821 
    822 	*cnt = nlwps;
    823 	return (kd->lwpbase);
    824 }
    825 
    826 struct kinfo_proc *
    827 kvm_getprocs(kvm_t *kd, int op, int arg, int *cnt)
    828 {
    829 	size_t size;
    830 	int mib[4], st, nprocs;
    831 
    832 	if (ISALIVE(kd)) {
    833 		size = 0;
    834 		mib[0] = CTL_KERN;
    835 		mib[1] = KERN_PROC;
    836 		mib[2] = op;
    837 		mib[3] = arg;
    838 		st = sysctl(mib, 4, NULL, &size, NULL, (size_t)0);
    839 		if (st == -1) {
    840 			_kvm_syserr(kd, kd->program, "kvm_getprocs");
    841 			return (NULL);
    842 		}
    843 		KVM_ALLOC(kd, procbase, size);
    844 		st = sysctl(mib, 4, kd->procbase, &size, NULL, (size_t)0);
    845 		if (st == -1) {
    846 			_kvm_syserr(kd, kd->program, "kvm_getprocs");
    847 			return (NULL);
    848 		}
    849 		if (size % sizeof(struct kinfo_proc) != 0) {
    850 			_kvm_err(kd, kd->program,
    851 			    "proc size mismatch (%lu total, %lu chunks)",
    852 			    (u_long)size, (u_long)sizeof(struct kinfo_proc));
    853 			return (NULL);
    854 		}
    855 		nprocs = (int) (size / sizeof(struct kinfo_proc));
    856 	} else {
    857 		struct nlist nl[4], *p;
    858 
    859 		(void)memset(nl, 0, sizeof(nl));
    860 		nl[0].n_name = "_nprocs";
    861 		nl[1].n_name = "_allproc";
    862 		nl[2].n_name = "_zombproc";
    863 		nl[3].n_name = NULL;
    864 
    865 		if (kvm_nlist(kd, nl) != 0) {
    866 			for (p = nl; p->n_type != 0; ++p)
    867 				continue;
    868 			_kvm_err(kd, kd->program,
    869 			    "%s: no such symbol", p->n_name);
    870 			return (NULL);
    871 		}
    872 		if (KREAD(kd, nl[0].n_value, &nprocs)) {
    873 			_kvm_err(kd, kd->program, "can't read nprocs");
    874 			return (NULL);
    875 		}
    876 		size = nprocs * sizeof(*kd->procbase);
    877 		KVM_ALLOC(kd, procbase, size);
    878 		nprocs = kvm_deadprocs(kd, op, arg, nl[1].n_value,
    879 		    nl[2].n_value, nprocs);
    880 		if (nprocs < 0)
    881 			return (NULL);
    882 #ifdef notdef
    883 		size = nprocs * sizeof(struct kinfo_proc);
    884 		(void)realloc(kd->procbase, size);
    885 #endif
    886 	}
    887 	*cnt = nprocs;
    888 	return (kd->procbase);
    889 }
    890 
    891 void *
    892 _kvm_realloc(kvm_t *kd, void *p, size_t n)
    893 {
    894 	void *np = realloc(p, n);
    895 
    896 	if (np == NULL)
    897 		_kvm_err(kd, kd->program, "out of memory");
    898 	return (np);
    899 }
    900 
    901 /*
    902  * Read in an argument vector from the user address space of process p.
    903  * addr if the user-space base address of narg null-terminated contiguous
    904  * strings.  This is used to read in both the command arguments and
    905  * environment strings.  Read at most maxcnt characters of strings.
    906  */
    907 static char **
    908 kvm_argv(kvm_t *kd, const struct miniproc *p, u_long addr, int narg,
    909 	 int maxcnt)
    910 {
    911 	char *np, *cp, *ep, *ap;
    912 	u_long oaddr = (u_long)~0L;
    913 	u_long len;
    914 	size_t cc;
    915 	char **argv;
    916 
    917 	/*
    918 	 * Check that there aren't an unreasonable number of arguments,
    919 	 * and that the address is in user space.
    920 	 */
    921 	if (narg > ARG_MAX || addr < kd->min_uva || addr >= kd->max_uva)
    922 		return (NULL);
    923 
    924 	if (kd->argv == NULL) {
    925 		/*
    926 		 * Try to avoid reallocs.
    927 		 */
    928 		kd->argc = MAX(narg + 1, 32);
    929 		kd->argv = _kvm_malloc(kd, kd->argc * sizeof(*kd->argv));
    930 		if (kd->argv == NULL)
    931 			return (NULL);
    932 	} else if (narg + 1 > kd->argc) {
    933 		kd->argc = MAX(2 * kd->argc, narg + 1);
    934 		kd->argv = _kvm_realloc(kd, kd->argv, kd->argc *
    935 		    sizeof(*kd->argv));
    936 		if (kd->argv == NULL)
    937 			return (NULL);
    938 	}
    939 	if (kd->argspc == NULL) {
    940 		kd->argspc = _kvm_malloc(kd, (size_t)kd->nbpg);
    941 		if (kd->argspc == NULL)
    942 			return (NULL);
    943 		kd->argspc_len = kd->nbpg;
    944 	}
    945 	if (kd->argbuf == NULL) {
    946 		kd->argbuf = _kvm_malloc(kd, (size_t)kd->nbpg);
    947 		if (kd->argbuf == NULL)
    948 			return (NULL);
    949 	}
    950 	cc = sizeof(char *) * narg;
    951 	if (kvm_ureadm(kd, p, addr, (void *)kd->argv, cc) != cc)
    952 		return (NULL);
    953 	ap = np = kd->argspc;
    954 	argv = kd->argv;
    955 	len = 0;
    956 	/*
    957 	 * Loop over pages, filling in the argument vector.
    958 	 */
    959 	while (argv < kd->argv + narg && *argv != NULL) {
    960 		addr = (u_long)*argv & ~(kd->nbpg - 1);
    961 		if (addr != oaddr) {
    962 			if (kvm_ureadm(kd, p, addr, kd->argbuf,
    963 			    (size_t)kd->nbpg) != kd->nbpg)
    964 				return (NULL);
    965 			oaddr = addr;
    966 		}
    967 		addr = (u_long)*argv & (kd->nbpg - 1);
    968 		cp = kd->argbuf + (size_t)addr;
    969 		cc = kd->nbpg - (size_t)addr;
    970 		if (maxcnt > 0 && cc > (size_t)(maxcnt - len))
    971 			cc = (size_t)(maxcnt - len);
    972 		ep = memchr(cp, '\0', cc);
    973 		if (ep != NULL)
    974 			cc = ep - cp + 1;
    975 		if (len + cc > kd->argspc_len) {
    976 			ptrdiff_t off;
    977 			char **pp;
    978 			char *op = kd->argspc;
    979 
    980 			kd->argspc_len *= 2;
    981 			kd->argspc = _kvm_realloc(kd, kd->argspc,
    982 			    kd->argspc_len);
    983 			if (kd->argspc == NULL)
    984 				return (NULL);
    985 			/*
    986 			 * Adjust argv pointers in case realloc moved
    987 			 * the string space.
    988 			 */
    989 			off = kd->argspc - op;
    990 			for (pp = kd->argv; pp < argv; pp++)
    991 				*pp += off;
    992 			ap += off;
    993 			np += off;
    994 		}
    995 		memcpy(np, cp, cc);
    996 		np += cc;
    997 		len += cc;
    998 		if (ep != NULL) {
    999 			*argv++ = ap;
   1000 			ap = np;
   1001 		} else
   1002 			*argv += cc;
   1003 		if (maxcnt > 0 && len >= maxcnt) {
   1004 			/*
   1005 			 * We're stopping prematurely.  Terminate the
   1006 			 * current string.
   1007 			 */
   1008 			if (ep == NULL) {
   1009 				*np = '\0';
   1010 				*argv++ = ap;
   1011 			}
   1012 			break;
   1013 		}
   1014 	}
   1015 	/* Make sure argv is terminated. */
   1016 	*argv = NULL;
   1017 	return (kd->argv);
   1018 }
   1019 
   1020 static void
   1021 ps_str_a(struct ps_strings *p, u_long *addr, int *n)
   1022 {
   1023 
   1024 	*addr = (u_long)p->ps_argvstr;
   1025 	*n = p->ps_nargvstr;
   1026 }
   1027 
   1028 static void
   1029 ps_str_e(struct ps_strings *p, u_long *addr, int *n)
   1030 {
   1031 
   1032 	*addr = (u_long)p->ps_envstr;
   1033 	*n = p->ps_nenvstr;
   1034 }
   1035 
   1036 /*
   1037  * Determine if the proc indicated by p is still active.
   1038  * This test is not 100% foolproof in theory, but chances of
   1039  * being wrong are very low.
   1040  */
   1041 static int
   1042 proc_verify(kvm_t *kd, u_long kernp, const struct miniproc *p)
   1043 {
   1044 	struct proc kernproc;
   1045 
   1046 	/*
   1047 	 * Just read in the whole proc.  It's not that big relative
   1048 	 * to the cost of the read system call.
   1049 	 */
   1050 	if (kvm_read(kd, kernp, &kernproc, sizeof(kernproc)) !=
   1051 	    sizeof(kernproc))
   1052 		return (0);
   1053 	return (p->p_pid == kernproc.p_pid &&
   1054 	    (kernproc.p_stat != SZOMB || p->p_stat == SZOMB));
   1055 }
   1056 
   1057 static char **
   1058 kvm_doargv(kvm_t *kd, const struct miniproc *p, int nchr,
   1059 	   void (*info)(struct ps_strings *, u_long *, int *))
   1060 {
   1061 	char **ap;
   1062 	u_long addr;
   1063 	int cnt;
   1064 	struct ps_strings arginfo;
   1065 
   1066 	/*
   1067 	 * Pointers are stored at the top of the user stack.
   1068 	 */
   1069 	if (p->p_stat == SZOMB)
   1070 		return (NULL);
   1071 	cnt = (int)kvm_ureadm(kd, p, kd->usrstack - sizeof(arginfo),
   1072 	    (void *)&arginfo, sizeof(arginfo));
   1073 	if (cnt != sizeof(arginfo))
   1074 		return (NULL);
   1075 
   1076 	(*info)(&arginfo, &addr, &cnt);
   1077 	if (cnt == 0)
   1078 		return (NULL);
   1079 	ap = kvm_argv(kd, p, addr, cnt, nchr);
   1080 	/*
   1081 	 * For live kernels, make sure this process didn't go away.
   1082 	 */
   1083 	if (ap != NULL && ISALIVE(kd) &&
   1084 	    !proc_verify(kd, (u_long)p->p_paddr, p))
   1085 		ap = NULL;
   1086 	return (ap);
   1087 }
   1088 
   1089 /*
   1090  * Get the command args.  This code is now machine independent.
   1091  */
   1092 char **
   1093 kvm_getargv(kvm_t *kd, const struct kinfo_proc *kp, int nchr)
   1094 {
   1095 	struct miniproc p;
   1096 
   1097 	KPTOMINI(kp, &p);
   1098 	return (kvm_doargv(kd, &p, nchr, ps_str_a));
   1099 }
   1100 
   1101 char **
   1102 kvm_getenvv(kvm_t *kd, const struct kinfo_proc *kp, int nchr)
   1103 {
   1104 	struct miniproc p;
   1105 
   1106 	KPTOMINI(kp, &p);
   1107 	return (kvm_doargv(kd, &p, nchr, ps_str_e));
   1108 }
   1109 
   1110 static char **
   1111 kvm_doargv2(kvm_t *kd, pid_t pid, int type, int nchr)
   1112 {
   1113 	size_t bufs;
   1114 	int narg, mib[4];
   1115 	size_t newargspc_len;
   1116 	char **ap, *bp, *endp;
   1117 
   1118 	/*
   1119 	 * Check that there aren't an unreasonable number of arguments.
   1120 	 */
   1121 	if (nchr > ARG_MAX)
   1122 		return (NULL);
   1123 
   1124 	if (nchr == 0)
   1125 		nchr = ARG_MAX;
   1126 
   1127 	/* Get number of strings in argv */
   1128 	mib[0] = CTL_KERN;
   1129 	mib[1] = KERN_PROC_ARGS;
   1130 	mib[2] = pid;
   1131 	mib[3] = type == KERN_PROC_ARGV ? KERN_PROC_NARGV : KERN_PROC_NENV;
   1132 	bufs = sizeof(narg);
   1133 	if (sysctl(mib, 4, &narg, &bufs, NULL, (size_t)0) == -1)
   1134 		return (NULL);
   1135 
   1136 	if (kd->argv == NULL) {
   1137 		/*
   1138 		 * Try to avoid reallocs.
   1139 		 */
   1140 		kd->argc = MAX(narg + 1, 32);
   1141 		kd->argv = _kvm_malloc(kd, kd->argc * sizeof(*kd->argv));
   1142 		if (kd->argv == NULL)
   1143 			return (NULL);
   1144 	} else if (narg + 1 > kd->argc) {
   1145 		kd->argc = MAX(2 * kd->argc, narg + 1);
   1146 		kd->argv = _kvm_realloc(kd, kd->argv, kd->argc *
   1147 		    sizeof(*kd->argv));
   1148 		if (kd->argv == NULL)
   1149 			return (NULL);
   1150 	}
   1151 
   1152 	newargspc_len = MIN(nchr, ARG_MAX);
   1153 	KVM_ALLOC(kd, argspc, newargspc_len);
   1154 	memset(kd->argspc, 0, (size_t)kd->argspc_len);	/* XXX necessary? */
   1155 
   1156 	mib[0] = CTL_KERN;
   1157 	mib[1] = KERN_PROC_ARGS;
   1158 	mib[2] = pid;
   1159 	mib[3] = type;
   1160 	bufs = kd->argspc_len;
   1161 	if (sysctl(mib, 4, kd->argspc, &bufs, NULL, (size_t)0) == -1)
   1162 		return (NULL);
   1163 
   1164 	bp = kd->argspc;
   1165 	bp[kd->argspc_len-1] = '\0';	/* make sure the string ends with nul */
   1166 	ap = kd->argv;
   1167 	endp = bp + MIN(nchr, bufs);
   1168 
   1169 	while (bp < endp) {
   1170 		*ap++ = bp;
   1171 		/*
   1172 		 * XXX: don't need following anymore, or stick check
   1173 		 * for max argc in above while loop?
   1174 		 */
   1175 		if (ap >= kd->argv + kd->argc) {
   1176 			kd->argc *= 2;
   1177 			kd->argv = _kvm_realloc(kd, kd->argv,
   1178 			    kd->argc * sizeof(*kd->argv));
   1179 			ap = kd->argv;
   1180 		}
   1181 		bp += strlen(bp) + 1;
   1182 	}
   1183 	*ap = NULL;
   1184 
   1185 	return (kd->argv);
   1186 }
   1187 
   1188 char **
   1189 kvm_getargv2(kvm_t *kd, const struct kinfo_proc2 *kp, int nchr)
   1190 {
   1191 
   1192 	return (kvm_doargv2(kd, kp->p_pid, KERN_PROC_ARGV, nchr));
   1193 }
   1194 
   1195 char **
   1196 kvm_getenvv2(kvm_t *kd, const struct kinfo_proc2 *kp, int nchr)
   1197 {
   1198 
   1199 	return (kvm_doargv2(kd, kp->p_pid, KERN_PROC_ENV, nchr));
   1200 }
   1201 
   1202 /*
   1203  * Read from user space.  The user context is given by p.
   1204  */
   1205 static ssize_t
   1206 kvm_ureadm(kvm_t *kd, const struct miniproc *p, u_long uva,
   1207 	   char *buf, size_t len)
   1208 {
   1209 	char *cp;
   1210 
   1211 	cp = buf;
   1212 	while (len > 0) {
   1213 		size_t cc;
   1214 		char *dp;
   1215 		u_long cnt;
   1216 
   1217 		dp = _kvm_ureadm(kd, p, uva, &cnt);
   1218 		if (dp == NULL) {
   1219 			_kvm_err(kd, 0, "invalid address (%lx)", uva);
   1220 			return (0);
   1221 		}
   1222 		cc = (size_t)MIN(cnt, len);
   1223 		memcpy(cp, dp, cc);
   1224 		cp += cc;
   1225 		uva += cc;
   1226 		len -= cc;
   1227 	}
   1228 	return (ssize_t)(cp - buf);
   1229 }
   1230 
   1231 ssize_t
   1232 kvm_uread(kvm_t *kd, const struct proc *p, u_long uva, char *buf, size_t len)
   1233 {
   1234 	struct miniproc mp;
   1235 
   1236 	PTOMINI(p, &mp);
   1237 	return (kvm_ureadm(kd, &mp, uva, buf, len));
   1238 }
   1239