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kvm_proc.c revision 1.99
      1 /*	$NetBSD: kvm_proc.c,v 1.99 2023/08/10 20:38:00 mrg 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 1.99 2023/08/10 20:38:00 mrg 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 	vaddr_t p_psstrp;
    122 	struct	proc *p_paddr;
    123 	pid_t	p_pid;
    124 };
    125 
    126 /*
    127  * Convert from struct proc and kinfo_proc{,2} to miniproc.
    128  */
    129 #define PTOMINI(kp, p) \
    130 	do { \
    131 		(p)->p_stat = (kp)->p_stat; \
    132 		(p)->p_pid = (kp)->p_pid; \
    133 		(p)->p_paddr = NULL; \
    134 		(p)->p_vmspace = (kp)->p_vmspace; \
    135 		(p)->p_psstrp = (kp)->p_psstrp; \
    136 	} while (0);
    137 
    138 #define KPTOMINI(kp, p) \
    139 	do { \
    140 		(p)->p_stat = (kp)->kp_proc.p_stat; \
    141 		(p)->p_pid = (kp)->kp_proc.p_pid; \
    142 		(p)->p_paddr = (kp)->kp_eproc.e_paddr; \
    143 		(p)->p_vmspace = (kp)->kp_proc.p_vmspace; \
    144 	} while (0);
    145 
    146 #define KP2TOMINI(kp, p) \
    147 	do { \
    148 		(p)->p_stat = (kp)->p_stat; \
    149 		(p)->p_pid = (kp)->p_pid; \
    150 		(p)->p_paddr = (void *)(long)(kp)->p_paddr; \
    151 		(p)->p_vmspace = (void *)(long)(kp)->p_vmspace; \
    152 	} while (0);
    153 
    154 /*
    155  * NetBSD uses kauth(9) to manage credentials, which are stored in kauth_cred_t,
    156  * a kernel-only opaque type. This is an embedded version which is *INTERNAL* to
    157  * kvm(3) so dumps can be read properly.
    158  *
    159  * Whenever NetBSD starts exporting credentials to userland consistently (using
    160  * 'struct uucred', or something) this will have to be updated again.
    161  */
    162 struct kvm_kauth_cred {
    163 	u_int cr_refcnt;		/* reference count */
    164 #if COHERENCY_UNIT > 4
    165 	uint8_t cr_pad[COHERENCY_UNIT - 4];
    166 #endif
    167 	uid_t cr_uid;			/* user id */
    168 	uid_t cr_euid;			/* effective user id */
    169 	uid_t cr_svuid;			/* saved effective user id */
    170 	gid_t cr_gid;			/* group id */
    171 	gid_t cr_egid;			/* effective group id */
    172 	gid_t cr_svgid;			/* saved effective group id */
    173 	u_int cr_ngroups;		/* number of groups */
    174 	gid_t cr_groups[NGROUPS];	/* group memberships */
    175 	specificdata_reference cr_sd;	/* specific data */
    176 };
    177 
    178 /* XXX: What uses these two functions? */
    179 char		*_kvm_uread(kvm_t *, const struct proc *, u_long, u_long *);
    180 ssize_t		kvm_uread(kvm_t *, const struct proc *, u_long, char *,
    181 		    size_t);
    182 
    183 static char	*_kvm_ureadm(kvm_t *, const struct miniproc *, u_long,
    184 		    u_long *);
    185 static ssize_t	kvm_ureadm(kvm_t *, const struct miniproc *, u_long,
    186 		    char *, size_t);
    187 
    188 static char	**kvm_argv(kvm_t *, const struct miniproc *, u_long, int, int);
    189 static int	kvm_deadprocs(kvm_t *, int, int, u_long, u_long, int);
    190 static char	**kvm_doargv(kvm_t *, const struct miniproc *, int,
    191 		    void (*)(struct ps_strings *, u_long *, int *));
    192 static char	**kvm_doargv2(kvm_t *, pid_t, int, int);
    193 static int	kvm_proclist(kvm_t *, int, int, struct proc *,
    194 		    struct kinfo_proc *, int);
    195 static int	proc_verify(kvm_t *, u_long, const struct miniproc *);
    196 static void	ps_str_a(struct ps_strings *, u_long *, int *);
    197 static void	ps_str_e(struct ps_strings *, u_long *, int *);
    198 
    199 
    200 static char *
    201 _kvm_ureadm(kvm_t *kd, const struct miniproc *p, u_long va, u_long *cnt)
    202 {
    203 	u_long addr, head;
    204 	u_long offset;
    205 	struct vm_map_entry vme;
    206 	struct vm_amap amap;
    207 	struct vm_anon *anonp, anon;
    208 	struct vm_page pg;
    209 	u_long slot;
    210 
    211 	if (kd->swapspc == NULL) {
    212 		kd->swapspc = _kvm_malloc(kd, (size_t)kd->nbpg);
    213 		if (kd->swapspc == NULL)
    214 			return (NULL);
    215 	}
    216 
    217 	/*
    218 	 * Look through the address map for the memory object
    219 	 * that corresponds to the given virtual address.
    220 	 * The header just has the entire valid range.
    221 	 */
    222 	head = (u_long)&p->p_vmspace->vm_map.header;
    223 	addr = head;
    224 	for (;;) {
    225 		if (KREAD(kd, addr, &vme))
    226 			return (NULL);
    227 
    228 		if (va >= vme.start && va < vme.end &&
    229 		    vme.aref.ar_amap != NULL)
    230 			break;
    231 
    232 		addr = (u_long)vme.next;
    233 		if (addr == head)
    234 			return (NULL);
    235 	}
    236 
    237 	/*
    238 	 * we found the map entry, now to find the object...
    239 	 */
    240 	if (vme.aref.ar_amap == NULL)
    241 		return (NULL);
    242 
    243 	addr = (u_long)vme.aref.ar_amap;
    244 	if (KREAD(kd, addr, &amap))
    245 		return (NULL);
    246 
    247 	offset = va - vme.start;
    248 	slot = offset / kd->nbpg + vme.aref.ar_pageoff;
    249 	/* sanity-check slot number */
    250 	if (slot > amap.am_nslot)
    251 		return (NULL);
    252 
    253 	addr = (u_long)amap.am_anon + (offset / kd->nbpg) * sizeof(anonp);
    254 	if (KREAD(kd, addr, &anonp))
    255 		return (NULL);
    256 
    257 	addr = (u_long)anonp;
    258 	if (KREAD(kd, addr, &anon))
    259 		return (NULL);
    260 
    261 	addr = (u_long)anon.an_page;
    262 	if (addr) {
    263 		if (KREAD(kd, addr, &pg))
    264 			return (NULL);
    265 
    266 		if (_kvm_pread(kd, kd->pmfd, kd->swapspc, (size_t)kd->nbpg,
    267 		    (off_t)pg.phys_addr & ~(kd->nbpg - 1)) != kd->nbpg)
    268 			return (NULL);
    269 	} else {
    270 		if (kd->swfd < 0 ||
    271 		    _kvm_pread(kd, kd->swfd, kd->swapspc, (size_t)kd->nbpg,
    272 		    (off_t)(anon.an_swslot * kd->nbpg)) != kd->nbpg)
    273 			return (NULL);
    274 	}
    275 
    276 	/* Found the page. */
    277 	offset %= kd->nbpg;
    278 	*cnt = kd->nbpg - offset;
    279 	return (&kd->swapspc[(size_t)offset]);
    280 }
    281 
    282 char *
    283 _kvm_uread(kvm_t *kd, const struct proc *p, u_long va, u_long *cnt)
    284 {
    285 	struct miniproc mp;
    286 
    287 	PTOMINI(p, &mp);
    288 	return (_kvm_ureadm(kd, &mp, va, cnt));
    289 }
    290 
    291 /*
    292  * Convert credentials located in kernel space address 'cred' and store
    293  * them in the appropriate members of 'eproc'.
    294  */
    295 static int
    296 _kvm_convertcred(kvm_t *kd, u_long cred, struct eproc *eproc)
    297 {
    298 	struct kvm_kauth_cred kauthcred;
    299 	struct ki_pcred *pc = &eproc->e_pcred;
    300 	struct ki_ucred *uc = &eproc->e_ucred;
    301 
    302 	if (KREAD(kd, cred, &kauthcred) != 0)
    303 		return (-1);
    304 
    305 	/* inlined version of kauth_cred_to_pcred, see kauth(9). */
    306 	pc->p_ruid = kauthcred.cr_uid;
    307 	pc->p_svuid = kauthcred.cr_svuid;
    308 	pc->p_rgid = kauthcred.cr_gid;
    309 	pc->p_svgid = kauthcred.cr_svgid;
    310 	pc->p_refcnt = kauthcred.cr_refcnt;
    311 	pc->p_pad = NULL;
    312 
    313 	/* inlined version of kauth_cred_to_ucred(), see kauth(9). */
    314 	uc->cr_ref = kauthcred.cr_refcnt;
    315 	uc->cr_uid = kauthcred.cr_euid;
    316 	uc->cr_gid = kauthcred.cr_egid;
    317 	uc->cr_ngroups = (uint32_t)MIN(kauthcred.cr_ngroups,
    318 	    sizeof(uc->cr_groups) / sizeof(uc->cr_groups[0]));
    319 	memcpy(uc->cr_groups, kauthcred.cr_groups,
    320 	    uc->cr_ngroups * sizeof(uc->cr_groups[0]));
    321 
    322 	return (0);
    323 }
    324 
    325 /*
    326  * Read proc's from memory file into buffer bp, which has space to hold
    327  * at most maxcnt procs.
    328  */
    329 static int
    330 kvm_proclist(kvm_t *kd, int what, int arg, struct proc *p,
    331 	     struct kinfo_proc *bp, int maxcnt)
    332 {
    333 	int cnt = 0;
    334 	int nlwps;
    335 	struct kinfo_lwp *kl;
    336 	struct eproc eproc;
    337 	struct pgrp pgrp;
    338 	struct session sess;
    339 	struct tty tty;
    340 	struct proc proc;
    341 
    342 	for (; cnt < maxcnt && p != NULL; p = proc.p_list.le_next) {
    343 		if (KREAD(kd, (u_long)p, &proc)) {
    344 			_kvm_err(kd, kd->program, "can't read proc at %p", p);
    345 			return (-1);
    346 		}
    347 		if (_kvm_convertcred(kd, (u_long)proc.p_cred, &eproc) != 0) {
    348 			_kvm_err(kd, kd->program,
    349 			    "can't read proc credentials at %p", p);
    350 			return (-1);
    351 		}
    352 
    353 		switch (what) {
    354 
    355 		case KERN_PROC_PID:
    356 			if (proc.p_pid != (pid_t)arg)
    357 				continue;
    358 			break;
    359 
    360 		case KERN_PROC_UID:
    361 			if (eproc.e_ucred.cr_uid != (uid_t)arg)
    362 				continue;
    363 			break;
    364 
    365 		case KERN_PROC_RUID:
    366 			if (eproc.e_pcred.p_ruid != (uid_t)arg)
    367 				continue;
    368 			break;
    369 		}
    370 		/*
    371 		 * We're going to add another proc to the set.  If this
    372 		 * will overflow the buffer, assume the reason is because
    373 		 * nprocs (or the proc list) is corrupt and declare an error.
    374 		 */
    375 		if (cnt >= maxcnt) {
    376 			_kvm_err(kd, kd->program, "nprocs corrupt");
    377 			return (-1);
    378 		}
    379 		/*
    380 		 * gather eproc
    381 		 */
    382 		eproc.e_paddr = p;
    383 		if (KREAD(kd, (u_long)proc.p_pgrp, &pgrp)) {
    384 			_kvm_err(kd, kd->program, "can't read pgrp at %p",
    385 			    proc.p_pgrp);
    386 			return (-1);
    387 		}
    388 		eproc.e_sess = pgrp.pg_session;
    389 		eproc.e_pgid = pgrp.pg_id;
    390 		eproc.e_jobc = pgrp.pg_jobc;
    391 		if (KREAD(kd, (u_long)pgrp.pg_session, &sess)) {
    392 			_kvm_err(kd, kd->program, "can't read session at %p",
    393 			    pgrp.pg_session);
    394 			return (-1);
    395 		}
    396 		if ((proc.p_lflag & PL_CONTROLT) && sess.s_ttyp != NULL) {
    397 			if (KREAD(kd, (u_long)sess.s_ttyp, &tty)) {
    398 				_kvm_err(kd, kd->program,
    399 				    "can't read tty at %p", sess.s_ttyp);
    400 				return (-1);
    401 			}
    402 			eproc.e_tdev = (uint32_t)tty.t_dev;
    403 			eproc.e_tsess = tty.t_session;
    404 			if (tty.t_pgrp != NULL) {
    405 				if (KREAD(kd, (u_long)tty.t_pgrp, &pgrp)) {
    406 					_kvm_err(kd, kd->program,
    407 					    "can't read tpgrp at %p",
    408 					    tty.t_pgrp);
    409 					return (-1);
    410 				}
    411 				eproc.e_tpgid = pgrp.pg_id;
    412 			} else
    413 				eproc.e_tpgid = -1;
    414 		} else
    415 			eproc.e_tdev = (uint32_t)NODEV;
    416 		eproc.e_flag = sess.s_ttyvp ? EPROC_CTTY : 0;
    417 		eproc.e_sid = sess.s_sid;
    418 		if (sess.s_leader == p)
    419 			eproc.e_flag |= EPROC_SLEADER;
    420 		/*
    421 		 * Fill in the old-style proc.p_wmesg by copying the wmesg
    422 		 * from the first available LWP.
    423 		 */
    424 		kl = kvm_getlwps(kd, proc.p_pid,
    425 		    (u_long)PTRTOUINT64(eproc.e_paddr),
    426 		    sizeof(struct kinfo_lwp), &nlwps);
    427 		if (kl) {
    428 			if (nlwps > 0) {
    429 				strcpy(eproc.e_wmesg, kl[0].l_wmesg);
    430 			}
    431 		}
    432 		(void)kvm_read(kd, (u_long)proc.p_vmspace, &eproc.e_vm,
    433 		    sizeof(eproc.e_vm));
    434 
    435 		eproc.e_xsize = eproc.e_xrssize = 0;
    436 		eproc.e_xccount = eproc.e_xswrss = 0;
    437 
    438 		switch (what) {
    439 
    440 		case KERN_PROC_PGRP:
    441 			if (eproc.e_pgid != (pid_t)arg)
    442 				continue;
    443 			break;
    444 
    445 		case KERN_PROC_TTY:
    446 			if ((proc.p_lflag & PL_CONTROLT) == 0 ||
    447 			    eproc.e_tdev != (dev_t)arg)
    448 				continue;
    449 			break;
    450 		}
    451 		memcpy(&bp->kp_proc, &proc, sizeof(proc));
    452 		memcpy(&bp->kp_eproc, &eproc, sizeof(eproc));
    453 		++bp;
    454 		++cnt;
    455 	}
    456 	return (cnt);
    457 }
    458 
    459 /*
    460  * Build proc info array by reading in proc list from a crash dump.
    461  * Return number of procs read.  maxcnt is the max we will read.
    462  */
    463 static int
    464 kvm_deadprocs(kvm_t *kd, int what, int arg, u_long a_allproc,
    465 	      u_long a_zombproc, int maxcnt)
    466 {
    467 	struct kinfo_proc *bp = kd->procbase;
    468 	int acnt, zcnt;
    469 	struct proc *p;
    470 
    471 	if (KREAD(kd, a_allproc, &p)) {
    472 		_kvm_err(kd, kd->program, "cannot read allproc");
    473 		return (-1);
    474 	}
    475 	acnt = kvm_proclist(kd, what, arg, p, bp, maxcnt);
    476 	if (acnt < 0)
    477 		return (acnt);
    478 
    479 	if (KREAD(kd, a_zombproc, &p)) {
    480 		_kvm_err(kd, kd->program, "cannot read zombproc");
    481 		return (-1);
    482 	}
    483 	zcnt = kvm_proclist(kd, what, arg, p, bp + acnt,
    484 	    maxcnt - acnt);
    485 	if (zcnt < 0)
    486 		zcnt = 0;
    487 
    488 	return (acnt + zcnt);
    489 }
    490 
    491 struct kinfo_proc2 *
    492 kvm_getproc2(kvm_t *kd, int op, int arg, size_t esize, int *cnt)
    493 {
    494 	size_t size;
    495 	int mib[6], st, nprocs;
    496 	struct pstats pstats;
    497 
    498 	if (ISSYSCTL(kd)) {
    499 		size = 0;
    500 		mib[0] = CTL_KERN;
    501 		mib[1] = KERN_PROC2;
    502 		mib[2] = op;
    503 		mib[3] = arg;
    504 		mib[4] = (int)esize;
    505 again:
    506 		mib[5] = 0;
    507 		st = sysctl(mib, 6, NULL, &size, NULL, (size_t)0);
    508 		if (st == -1) {
    509 			_kvm_syserr(kd, kd->program, "kvm_getproc2");
    510 			return (NULL);
    511 		}
    512 
    513 		mib[5] = (int) (size / esize);
    514 		KVM_ALLOC(kd, procbase2, size);
    515 		st = sysctl(mib, 6, kd->procbase2, &size, NULL, (size_t)0);
    516 		if (st == -1) {
    517 			if (errno == ENOMEM) {
    518 				goto again;
    519 			}
    520 			_kvm_syserr(kd, kd->program, "kvm_getproc2");
    521 			return (NULL);
    522 		}
    523 		nprocs = (int) (size / esize);
    524 	} else {
    525 		char *kp2c;
    526 		struct kinfo_proc *kp;
    527 		struct kinfo_proc2 kp2, *kp2p;
    528 		struct kinfo_lwp *kl;
    529 		int i, nlwps;
    530 
    531 		kp = kvm_getprocs(kd, op, arg, &nprocs);
    532 		if (kp == NULL)
    533 			return (NULL);
    534 
    535 		size = nprocs * esize;
    536 		KVM_ALLOC(kd, procbase2, size);
    537 		kp2c = (char *)(void *)kd->procbase2;
    538 		kp2p = &kp2;
    539 		for (i = 0; i < nprocs; i++, kp++) {
    540 			struct timeval tv;
    541 
    542 			kl = kvm_getlwps(kd, kp->kp_proc.p_pid,
    543 			    (u_long)PTRTOUINT64(kp->kp_eproc.e_paddr),
    544 			    sizeof(struct kinfo_lwp), &nlwps);
    545 
    546 			if (kl == NULL) {
    547 				_kvm_syserr(kd, NULL,
    548 					"kvm_getlwps() failed on process %u\n",
    549 					kp->kp_proc.p_pid);
    550 				if (nlwps == 0)
    551 					return NULL;
    552 				else
    553 					continue;
    554 			}
    555 
    556 			/* We use kl[0] as the "representative" LWP */
    557 			memset(kp2p, 0, sizeof(kp2));
    558 			kp2p->p_forw = kl[0].l_forw;
    559 			kp2p->p_back = kl[0].l_back;
    560 			kp2p->p_paddr = PTRTOUINT64(kp->kp_eproc.e_paddr);
    561 			kp2p->p_addr = kl[0].l_addr;
    562 			kp2p->p_fd = PTRTOUINT64(kp->kp_proc.p_fd);
    563 			kp2p->p_cwdi = PTRTOUINT64(kp->kp_proc.p_cwdi);
    564 			kp2p->p_stats = PTRTOUINT64(kp->kp_proc.p_stats);
    565 			kp2p->p_limit = PTRTOUINT64(kp->kp_proc.p_limit);
    566 			kp2p->p_vmspace = PTRTOUINT64(kp->kp_proc.p_vmspace);
    567 			kp2p->p_sigacts = PTRTOUINT64(kp->kp_proc.p_sigacts);
    568 			kp2p->p_sess = PTRTOUINT64(kp->kp_eproc.e_sess);
    569 			kp2p->p_tsess = 0;
    570 #if 1 /* XXX: dsl - p_ru was only ever non-zero for zombies */
    571 			kp2p->p_ru = 0;
    572 #else
    573 			kp2p->p_ru = PTRTOUINT64(pstats.p_ru);
    574 #endif
    575 
    576 			kp2p->p_eflag = 0;
    577 			kp2p->p_exitsig = kp->kp_proc.p_exitsig;
    578 			kp2p->p_flag = kp->kp_proc.p_flag;
    579 
    580 			kp2p->p_pid = kp->kp_proc.p_pid;
    581 
    582 			kp2p->p_ppid = kp->kp_eproc.e_ppid;
    583 			kp2p->p_sid = kp->kp_eproc.e_sid;
    584 			kp2p->p__pgid = kp->kp_eproc.e_pgid;
    585 
    586 			kp2p->p_tpgid = -1 /* XXX NO_PGID! */;
    587 
    588 			kp2p->p_uid = kp->kp_eproc.e_ucred.cr_uid;
    589 			kp2p->p_ruid = kp->kp_eproc.e_pcred.p_ruid;
    590 			kp2p->p_svuid = kp->kp_eproc.e_pcred.p_svuid;
    591 			kp2p->p_gid = kp->kp_eproc.e_ucred.cr_gid;
    592 			kp2p->p_rgid = kp->kp_eproc.e_pcred.p_rgid;
    593 			kp2p->p_svgid = kp->kp_eproc.e_pcred.p_svgid;
    594 
    595 			/*CONSTCOND*/
    596 			memcpy(kp2p->p_groups, kp->kp_eproc.e_ucred.cr_groups,
    597 			    MIN(sizeof(kp2p->p_groups),
    598 			    sizeof(kp->kp_eproc.e_ucred.cr_groups)));
    599 			kp2p->p_ngroups = kp->kp_eproc.e_ucred.cr_ngroups;
    600 
    601 			kp2p->p_jobc = kp->kp_eproc.e_jobc;
    602 			kp2p->p_tdev = kp->kp_eproc.e_tdev;
    603 			kp2p->p_tpgid = kp->kp_eproc.e_tpgid;
    604 			kp2p->p_tsess = PTRTOUINT64(kp->kp_eproc.e_tsess);
    605 
    606 			kp2p->p_estcpu = 0;
    607 			bintime2timeval(&kp->kp_proc.p_rtime, &tv);
    608 			kp2p->p_rtime_sec = (uint32_t)tv.tv_sec;
    609 			kp2p->p_rtime_usec = (uint32_t)tv.tv_usec;
    610 			kp2p->p_cpticks = kl[0].l_cpticks;
    611 			kp2p->p_pctcpu = kp->kp_proc.p_pctcpu;
    612 			kp2p->p_swtime = kl[0].l_swtime;
    613 			kp2p->p_slptime = kl[0].l_slptime;
    614 #if 0 /* XXX thorpej */
    615 			kp2p->p_schedflags = kp->kp_proc.p_schedflags;
    616 #else
    617 			kp2p->p_schedflags = 0;
    618 #endif
    619 
    620 			kp2p->p_uticks = kp->kp_proc.p_uticks;
    621 			kp2p->p_sticks = kp->kp_proc.p_sticks;
    622 			kp2p->p_iticks = kp->kp_proc.p_iticks;
    623 
    624 			kp2p->p_tracep = PTRTOUINT64(kp->kp_proc.p_tracep);
    625 			kp2p->p_traceflag = kp->kp_proc.p_traceflag;
    626 
    627 			kp2p->p_holdcnt = kl[0].l_holdcnt;
    628 
    629 			memcpy(&kp2p->p_siglist,
    630 			    &kp->kp_proc.p_sigpend.sp_set,
    631 			    sizeof(ki_sigset_t));
    632 			memset(&kp2p->p_sigmask, 0,
    633 			    sizeof(ki_sigset_t));
    634 			memcpy(&kp2p->p_sigignore,
    635 			    &kp->kp_proc.p_sigctx.ps_sigignore,
    636 			    sizeof(ki_sigset_t));
    637 			memcpy(&kp2p->p_sigcatch,
    638 			    &kp->kp_proc.p_sigctx.ps_sigcatch,
    639 			    sizeof(ki_sigset_t));
    640 
    641 			kp2p->p_stat = kl[0].l_stat;
    642 			kp2p->p_priority = kl[0].l_priority;
    643 			kp2p->p_usrpri = kl[0].l_priority;
    644 			kp2p->p_nice = kp->kp_proc.p_nice;
    645 
    646 			kp2p->p_xstat = P_WAITSTATUS(&kp->kp_proc);
    647 			kp2p->p_acflag = kp->kp_proc.p_acflag;
    648 
    649 			/*CONSTCOND*/
    650 			strncpy(kp2p->p_comm, kp->kp_proc.p_comm,
    651 			    MIN(sizeof(kp2p->p_comm),
    652 			    sizeof(kp->kp_proc.p_comm)));
    653 
    654 			strncpy(kp2p->p_wmesg, kp->kp_eproc.e_wmesg,
    655 			    sizeof(kp2p->p_wmesg));
    656 			kp2p->p_wchan = kl[0].l_wchan;
    657 			strncpy(kp2p->p_login, kp->kp_eproc.e_login,
    658 			    sizeof(kp2p->p_login));
    659 
    660 			kp2p->p_vm_rssize = kp->kp_eproc.e_xrssize;
    661 			kp2p->p_vm_tsize = kp->kp_eproc.e_vm.vm_tsize;
    662 			kp2p->p_vm_dsize = kp->kp_eproc.e_vm.vm_dsize;
    663 			kp2p->p_vm_ssize = kp->kp_eproc.e_vm.vm_ssize;
    664 			kp2p->p_vm_vsize = kp->kp_eproc.e_vm.vm_map.size
    665 			    / kd->nbpg;
    666 			/* Adjust mapped size */
    667 			kp2p->p_vm_msize =
    668 			    (kp->kp_eproc.e_vm.vm_map.size / kd->nbpg) -
    669 			    kp->kp_eproc.e_vm.vm_issize +
    670 			    kp->kp_eproc.e_vm.vm_ssize;
    671 
    672 			kp2p->p_eflag = (int32_t)kp->kp_eproc.e_flag;
    673 
    674 			kp2p->p_realflag = kp->kp_proc.p_flag;
    675 			kp2p->p_nlwps = kp->kp_proc.p_nlwps;
    676 			kp2p->p_nrlwps = kp->kp_proc.p_nrlwps;
    677 			kp2p->p_realstat = kp->kp_proc.p_stat;
    678 
    679 			if (P_ZOMBIE(&kp->kp_proc) ||
    680 			    kp->kp_proc.p_stats == NULL ||
    681 			    KREAD(kd, (u_long)kp->kp_proc.p_stats, &pstats)) {
    682 				kp2p->p_uvalid = 0;
    683 			} else {
    684 				kp2p->p_uvalid = 1;
    685 
    686 				kp2p->p_ustart_sec = (u_int32_t)
    687 				    pstats.p_start.tv_sec;
    688 				kp2p->p_ustart_usec = (u_int32_t)
    689 				    pstats.p_start.tv_usec;
    690 
    691 				kp2p->p_uutime_sec = (u_int32_t)
    692 				    pstats.p_ru.ru_utime.tv_sec;
    693 				kp2p->p_uutime_usec = (u_int32_t)
    694 				    pstats.p_ru.ru_utime.tv_usec;
    695 				kp2p->p_ustime_sec = (u_int32_t)
    696 				    pstats.p_ru.ru_stime.tv_sec;
    697 				kp2p->p_ustime_usec = (u_int32_t)
    698 				    pstats.p_ru.ru_stime.tv_usec;
    699 
    700 				kp2p->p_uru_maxrss = pstats.p_ru.ru_maxrss;
    701 				kp2p->p_uru_ixrss = pstats.p_ru.ru_ixrss;
    702 				kp2p->p_uru_idrss = pstats.p_ru.ru_idrss;
    703 				kp2p->p_uru_isrss = pstats.p_ru.ru_isrss;
    704 				kp2p->p_uru_minflt = pstats.p_ru.ru_minflt;
    705 				kp2p->p_uru_majflt = pstats.p_ru.ru_majflt;
    706 				kp2p->p_uru_nswap = pstats.p_ru.ru_nswap;
    707 				kp2p->p_uru_inblock = pstats.p_ru.ru_inblock;
    708 				kp2p->p_uru_oublock = pstats.p_ru.ru_oublock;
    709 				kp2p->p_uru_msgsnd = pstats.p_ru.ru_msgsnd;
    710 				kp2p->p_uru_msgrcv = pstats.p_ru.ru_msgrcv;
    711 				kp2p->p_uru_nsignals = pstats.p_ru.ru_nsignals;
    712 				kp2p->p_uru_nvcsw = pstats.p_ru.ru_nvcsw;
    713 				kp2p->p_uru_nivcsw = pstats.p_ru.ru_nivcsw;
    714 
    715 				kp2p->p_uctime_sec = (u_int32_t)
    716 				    (pstats.p_cru.ru_utime.tv_sec +
    717 				    pstats.p_cru.ru_stime.tv_sec);
    718 				kp2p->p_uctime_usec = (u_int32_t)
    719 				    (pstats.p_cru.ru_utime.tv_usec +
    720 				    pstats.p_cru.ru_stime.tv_usec);
    721 			}
    722 
    723 			memcpy(kp2c, &kp2, esize);
    724 			kp2c += esize;
    725 		}
    726 	}
    727 	*cnt = nprocs;
    728 	return (kd->procbase2);
    729 }
    730 
    731 struct kinfo_lwp *
    732 kvm_getlwps(kvm_t *kd, int pid, u_long paddr, size_t esize, int *cnt)
    733 {
    734 	size_t size;
    735 	int mib[5], nlwps;
    736 	ssize_t st;
    737 	struct kinfo_lwp *kl;
    738 
    739 	if (ISSYSCTL(kd)) {
    740 		size = 0;
    741 		mib[0] = CTL_KERN;
    742 		mib[1] = KERN_LWP;
    743 		mib[2] = pid;
    744 		mib[3] = (int)esize;
    745 		mib[4] = 0;
    746 again:
    747 		st = sysctl(mib, 5, NULL, &size, NULL, (size_t)0);
    748 		if (st == -1) {
    749 			switch (errno) {
    750 			case ESRCH: /* Treat this as a soft error; see kvm.c */
    751 				_kvm_syserr(kd, NULL, "kvm_getlwps");
    752 				return NULL;
    753 			default:
    754 				_kvm_syserr(kd, kd->program, "kvm_getlwps");
    755 				return NULL;
    756 			}
    757 		}
    758 		mib[4] = (int) (size / esize);
    759 		KVM_ALLOC(kd, lwpbase, size);
    760 		st = sysctl(mib, 5, kd->lwpbase, &size, NULL, (size_t)0);
    761 		if (st == -1) {
    762 			switch (errno) {
    763 			case ESRCH: /* Treat this as a soft error; see kvm.c */
    764 				_kvm_syserr(kd, NULL, "kvm_getlwps");
    765 				return NULL;
    766 			case ENOMEM:
    767 				goto again;
    768 			default:
    769 				_kvm_syserr(kd, kd->program, "kvm_getlwps");
    770 				return NULL;
    771 			}
    772 		}
    773 		nlwps = (int) (size / esize);
    774 	} else {
    775 		/* grovel through the memory image */
    776 		struct proc p;
    777 		struct lwp l;
    778 		u_long laddr;
    779 		void *back;
    780 		int i;
    781 
    782 		st = kvm_read(kd, paddr, &p, sizeof(p));
    783 		if (st == -1) {
    784 			_kvm_syserr(kd, kd->program, "kvm_getlwps");
    785 			return (NULL);
    786 		}
    787 
    788 		nlwps = p.p_nlwps;
    789 		size = nlwps * sizeof(*kd->lwpbase);
    790 		KVM_ALLOC(kd, lwpbase, size);
    791 		laddr = (u_long)PTRTOUINT64(p.p_lwps.lh_first);
    792 		for (i = 0; (i < nlwps) && (laddr != 0); i++) {
    793 			st = kvm_read(kd, laddr, &l, sizeof(l));
    794 			if (st == -1) {
    795 				_kvm_syserr(kd, kd->program, "kvm_getlwps");
    796 				return (NULL);
    797 			}
    798 			kl = &kd->lwpbase[i];
    799 			kl->l_laddr = laddr;
    800 			kl->l_forw = PTRTOUINT64(l.l_runq.tqe_next);
    801 			laddr = (u_long)PTRTOUINT64(l.l_runq.tqe_prev);
    802 			st = kvm_read(kd, laddr, &back, sizeof(back));
    803 			if (st == -1) {
    804 				_kvm_syserr(kd, kd->program, "kvm_getlwps");
    805 				return (NULL);
    806 			}
    807 			kl->l_back = PTRTOUINT64(back);
    808 			kl->l_addr = PTRTOUINT64(l.l_addr);
    809 			kl->l_lid = l.l_lid;
    810 			kl->l_flag = l.l_flag;
    811 			kl->l_swtime = l.l_swtime;
    812 			kl->l_slptime = l.l_slptime;
    813 			kl->l_schedflags = 0; /* XXX */
    814 			kl->l_holdcnt = 0;
    815 			kl->l_priority = l.l_priority;
    816 			kl->l_usrpri = l.l_priority;
    817 			kl->l_stat = l.l_stat;
    818 			kl->l_wchan = PTRTOUINT64(l.l_wchan);
    819 			if (l.l_wmesg)
    820 				(void)kvm_read(kd, (u_long)l.l_wmesg,
    821 				    kl->l_wmesg, (size_t)WMESGLEN);
    822 			kl->l_cpuid = KI_NOCPU;
    823 			laddr = (u_long)PTRTOUINT64(l.l_sibling.le_next);
    824 		}
    825 	}
    826 
    827 	*cnt = nlwps;
    828 	return (kd->lwpbase);
    829 }
    830 
    831 struct kinfo_proc *
    832 kvm_getprocs(kvm_t *kd, int op, int arg, int *cnt)
    833 {
    834 	size_t size;
    835 	int mib[4], st, nprocs;
    836 
    837 	if (ISALIVE(kd)) {
    838 		size = 0;
    839 		mib[0] = CTL_KERN;
    840 		mib[1] = KERN_PROC;
    841 		mib[2] = op;
    842 		mib[3] = arg;
    843 		st = sysctl(mib, 4, NULL, &size, NULL, (size_t)0);
    844 		if (st == -1) {
    845 			_kvm_syserr(kd, kd->program, "kvm_getprocs");
    846 			return (NULL);
    847 		}
    848 		KVM_ALLOC(kd, procbase, size);
    849 		st = sysctl(mib, 4, kd->procbase, &size, NULL, (size_t)0);
    850 		if (st == -1) {
    851 			_kvm_syserr(kd, kd->program, "kvm_getprocs");
    852 			return (NULL);
    853 		}
    854 		if (size % sizeof(struct kinfo_proc) != 0) {
    855 			_kvm_err(kd, kd->program,
    856 			    "proc size mismatch (%lu total, %lu chunks)",
    857 			    (u_long)size, (u_long)sizeof(struct kinfo_proc));
    858 			return (NULL);
    859 		}
    860 		nprocs = (int) (size / sizeof(struct kinfo_proc));
    861 	} else {
    862 		struct nlist nl[4], *p;
    863 
    864 		(void)memset(nl, 0, sizeof(nl));
    865 		nl[0].n_name = "_nprocs";
    866 		nl[1].n_name = "_allproc";
    867 		nl[2].n_name = "_zombproc";
    868 		nl[3].n_name = NULL;
    869 
    870 		if (kvm_nlist(kd, nl) != 0) {
    871 			for (p = nl; p->n_type != 0; ++p)
    872 				continue;
    873 			_kvm_err(kd, kd->program,
    874 			    "%s: no such symbol", p->n_name);
    875 			return (NULL);
    876 		}
    877 		if (KREAD(kd, nl[0].n_value, &nprocs)) {
    878 			_kvm_err(kd, kd->program, "can't read nprocs");
    879 			return (NULL);
    880 		}
    881 		size = nprocs * sizeof(*kd->procbase);
    882 		KVM_ALLOC(kd, procbase, size);
    883 		nprocs = kvm_deadprocs(kd, op, arg, nl[1].n_value,
    884 		    nl[2].n_value, nprocs);
    885 		if (nprocs < 0)
    886 			return (NULL);
    887 #ifdef notdef
    888 		size = nprocs * sizeof(struct kinfo_proc);
    889 		(void)realloc(kd->procbase, size);
    890 #endif
    891 	}
    892 	*cnt = nprocs;
    893 	return (kd->procbase);
    894 }
    895 
    896 void *
    897 _kvm_realloc(kvm_t *kd, void *p, size_t n)
    898 {
    899 	void *np = realloc(p, n);
    900 
    901 	if (np == NULL)
    902 		_kvm_err(kd, kd->program, "out of memory");
    903 	return (np);
    904 }
    905 
    906 /*
    907  * Read in an argument vector from the user address space of process p.
    908  * addr if the user-space base address of narg null-terminated contiguous
    909  * strings.  This is used to read in both the command arguments and
    910  * environment strings.  Read at most maxcnt characters of strings.
    911  */
    912 static char **
    913 kvm_argv(kvm_t *kd, const struct miniproc *p, u_long addr, int narg,
    914 	 int maxcnt)
    915 {
    916 	char *np, *cp, *ep, *ap;
    917 	u_long oaddr = (u_long)~0L;
    918 	u_long len;
    919 	size_t cc;
    920 	char **argv;
    921 
    922 	/*
    923 	 * Check that there aren't an unreasonable number of arguments,
    924 	 * and that the address is in user space.
    925 	 */
    926 	if (narg > ARG_MAX || addr < kd->min_uva || addr >= kd->max_uva)
    927 		return (NULL);
    928 
    929 	if (kd->argv == NULL) {
    930 		/*
    931 		 * Try to avoid reallocs.
    932 		 */
    933 		kd->argc = MAX(narg + 1, 32);
    934 		kd->argv = _kvm_malloc(kd, kd->argc * sizeof(*kd->argv));
    935 		if (kd->argv == NULL)
    936 			return (NULL);
    937 	} else if (narg + 1 > kd->argc) {
    938 		kd->argc = MAX(2 * kd->argc, narg + 1);
    939 		kd->argv = _kvm_realloc(kd, kd->argv, kd->argc *
    940 		    sizeof(*kd->argv));
    941 		if (kd->argv == NULL)
    942 			return (NULL);
    943 	}
    944 	if (kd->argspc == NULL) {
    945 		kd->argspc = _kvm_malloc(kd, (size_t)kd->nbpg);
    946 		if (kd->argspc == NULL)
    947 			return (NULL);
    948 		kd->argspc_len = kd->nbpg;
    949 	}
    950 	if (kd->argbuf == NULL) {
    951 		kd->argbuf = _kvm_malloc(kd, (size_t)kd->nbpg);
    952 		if (kd->argbuf == NULL)
    953 			return (NULL);
    954 	}
    955 	cc = sizeof(char *) * narg;
    956 	if (kvm_ureadm(kd, p, addr, (void *)kd->argv, cc) != cc)
    957 		return (NULL);
    958 	ap = np = kd->argspc;
    959 	argv = kd->argv;
    960 	len = 0;
    961 	/*
    962 	 * Loop over pages, filling in the argument vector.
    963 	 */
    964 	while (argv < kd->argv + narg && *argv != NULL) {
    965 		addr = (u_long)*argv & ~(kd->nbpg - 1);
    966 		if (addr != oaddr) {
    967 			if (kvm_ureadm(kd, p, addr, kd->argbuf,
    968 			    (size_t)kd->nbpg) != kd->nbpg)
    969 				return (NULL);
    970 			oaddr = addr;
    971 		}
    972 		addr = (u_long)*argv & (kd->nbpg - 1);
    973 		cp = kd->argbuf + (size_t)addr;
    974 		cc = kd->nbpg - (size_t)addr;
    975 		if (maxcnt > 0 && cc > (size_t)(maxcnt - len))
    976 			cc = (size_t)(maxcnt - len);
    977 		ep = memchr(cp, '\0', cc);
    978 		if (ep != NULL)
    979 			cc = ep - cp + 1;
    980 		if (len + cc > kd->argspc_len) {
    981 			ptrdiff_t off;
    982 			char **pp;
    983 			uintptr_t op = (uintptr_t)kd->argspc;
    984 
    985 			kd->argspc_len *= 2;
    986 			kd->argspc = _kvm_realloc(kd, kd->argspc,
    987 			    kd->argspc_len);
    988 			if (kd->argspc == NULL)
    989 				return (NULL);
    990 			/*
    991 			 * Adjust argv pointers in case realloc moved
    992 			 * the string space.
    993 			 */
    994 			off = (uintptr_t)kd->argspc - op;
    995 			for (pp = kd->argv; pp < argv; pp++)
    996 				*pp += off;
    997 			ap += off;
    998 			np += off;
    999 		}
   1000 		memcpy(np, cp, cc);
   1001 		np += cc;
   1002 		len += cc;
   1003 		if (ep != NULL) {
   1004 			*argv++ = ap;
   1005 			ap = np;
   1006 		} else
   1007 			*argv += cc;
   1008 		if (maxcnt > 0 && len >= maxcnt) {
   1009 			/*
   1010 			 * We're stopping prematurely.  Terminate the
   1011 			 * current string.
   1012 			 */
   1013 			if (ep == NULL) {
   1014 				*np = '\0';
   1015 				*argv++ = ap;
   1016 			}
   1017 			break;
   1018 		}
   1019 	}
   1020 	/* Make sure argv is terminated. */
   1021 	*argv = NULL;
   1022 	return (kd->argv);
   1023 }
   1024 
   1025 static void
   1026 ps_str_a(struct ps_strings *p, u_long *addr, int *n)
   1027 {
   1028 
   1029 	*addr = (u_long)p->ps_argvstr;
   1030 	*n = p->ps_nargvstr;
   1031 }
   1032 
   1033 static void
   1034 ps_str_e(struct ps_strings *p, u_long *addr, int *n)
   1035 {
   1036 
   1037 	*addr = (u_long)p->ps_envstr;
   1038 	*n = p->ps_nenvstr;
   1039 }
   1040 
   1041 /*
   1042  * Determine if the proc indicated by p is still active.
   1043  * This test is not 100% foolproof in theory, but chances of
   1044  * being wrong are very low.
   1045  */
   1046 static int
   1047 proc_verify(kvm_t *kd, u_long kernp, const struct miniproc *p)
   1048 {
   1049 	struct proc kernproc;
   1050 
   1051 	/*
   1052 	 * Just read in the whole proc.  It's not that big relative
   1053 	 * to the cost of the read system call.
   1054 	 */
   1055 	if (kvm_read(kd, kernp, &kernproc, sizeof(kernproc)) !=
   1056 	    sizeof(kernproc))
   1057 		return (0);
   1058 	return (p->p_pid == kernproc.p_pid &&
   1059 	    (kernproc.p_stat != SZOMB || p->p_stat == SZOMB));
   1060 }
   1061 
   1062 static char **
   1063 kvm_doargv(kvm_t *kd, const struct miniproc *p, int nchr,
   1064 	   void (*info)(struct ps_strings *, u_long *, int *))
   1065 {
   1066 	char **ap;
   1067 	u_long addr;
   1068 	int cnt;
   1069 	struct ps_strings arginfo;
   1070 
   1071 	/*
   1072 	 * Pointers are stored at the top of the user stack.
   1073 	 */
   1074 	if (p->p_stat == SZOMB)
   1075 		return (NULL);
   1076 	cnt = (int)kvm_ureadm(kd, p, p->p_psstrp,
   1077 	    (void *)&arginfo, sizeof(arginfo));
   1078 	if (cnt != sizeof(arginfo))
   1079 		return (NULL);
   1080 
   1081 	(*info)(&arginfo, &addr, &cnt);
   1082 	if (cnt == 0)
   1083 		return (NULL);
   1084 	ap = kvm_argv(kd, p, addr, cnt, nchr);
   1085 	/*
   1086 	 * For live kernels, make sure this process didn't go away.
   1087 	 */
   1088 	if (ap != NULL && ISALIVE(kd) &&
   1089 	    !proc_verify(kd, (u_long)p->p_paddr, p))
   1090 		ap = NULL;
   1091 	return (ap);
   1092 }
   1093 
   1094 /*
   1095  * Get the command args.  This code is now machine independent.
   1096  */
   1097 char **
   1098 kvm_getargv(kvm_t *kd, const struct kinfo_proc *kp, int nchr)
   1099 {
   1100 	struct miniproc p;
   1101 
   1102 	KPTOMINI(kp, &p);
   1103 	return (kvm_doargv(kd, &p, nchr, ps_str_a));
   1104 }
   1105 
   1106 char **
   1107 kvm_getenvv(kvm_t *kd, const struct kinfo_proc *kp, int nchr)
   1108 {
   1109 	struct miniproc p;
   1110 
   1111 	KPTOMINI(kp, &p);
   1112 	return (kvm_doargv(kd, &p, nchr, ps_str_e));
   1113 }
   1114 
   1115 static char **
   1116 kvm_doargv2(kvm_t *kd, pid_t pid, int type, int nchr)
   1117 {
   1118 	size_t bufs;
   1119 	int narg, mib[4];
   1120 	size_t newargspc_len;
   1121 	char **ap, *bp, *endp;
   1122 
   1123 	/*
   1124 	 * Check that there aren't an unreasonable number of arguments.
   1125 	 */
   1126 	if (nchr > ARG_MAX)
   1127 		return (NULL);
   1128 
   1129 	if (nchr == 0)
   1130 		nchr = ARG_MAX;
   1131 
   1132 	/* Get number of strings in argv */
   1133 	mib[0] = CTL_KERN;
   1134 	mib[1] = KERN_PROC_ARGS;
   1135 	mib[2] = pid;
   1136 	mib[3] = type == KERN_PROC_ARGV ? KERN_PROC_NARGV : KERN_PROC_NENV;
   1137 	bufs = sizeof(narg);
   1138 	if (sysctl(mib, 4, &narg, &bufs, NULL, (size_t)0) == -1)
   1139 		return (NULL);
   1140 
   1141 	if (kd->argv == NULL) {
   1142 		/*
   1143 		 * Try to avoid reallocs.
   1144 		 */
   1145 		kd->argc = MAX(narg + 1, 32);
   1146 		kd->argv = _kvm_malloc(kd, kd->argc * sizeof(*kd->argv));
   1147 		if (kd->argv == NULL)
   1148 			return (NULL);
   1149 	} else if (narg + 1 > kd->argc) {
   1150 		kd->argc = MAX(2 * kd->argc, narg + 1);
   1151 		kd->argv = _kvm_realloc(kd, kd->argv, kd->argc *
   1152 		    sizeof(*kd->argv));
   1153 		if (kd->argv == NULL)
   1154 			return (NULL);
   1155 	}
   1156 
   1157 	newargspc_len = MIN(nchr, ARG_MAX);
   1158 	KVM_ALLOC(kd, argspc, newargspc_len);
   1159 	memset(kd->argspc, 0, (size_t)kd->argspc_len);	/* XXX necessary? */
   1160 
   1161 	mib[0] = CTL_KERN;
   1162 	mib[1] = KERN_PROC_ARGS;
   1163 	mib[2] = pid;
   1164 	mib[3] = type;
   1165 	bufs = kd->argspc_len;
   1166 	if (sysctl(mib, 4, kd->argspc, &bufs, NULL, (size_t)0) == -1)
   1167 		return (NULL);
   1168 
   1169 	bp = kd->argspc;
   1170 	bp[kd->argspc_len-1] = '\0';	/* make sure the string ends with nul */
   1171 	ap = kd->argv;
   1172 	endp = bp + MIN(nchr, bufs);
   1173 
   1174 	while (bp < endp) {
   1175 		*ap++ = bp;
   1176 		/*
   1177 		 * XXX: don't need following anymore, or stick check
   1178 		 * for max argc in above while loop?
   1179 		 */
   1180 		if (ap >= kd->argv + kd->argc) {
   1181 			kd->argc *= 2;
   1182 			kd->argv = _kvm_realloc(kd, kd->argv,
   1183 			    kd->argc * sizeof(*kd->argv));
   1184 			ap = kd->argv;
   1185 		}
   1186 		bp += strlen(bp) + 1;
   1187 	}
   1188 	*ap = NULL;
   1189 
   1190 	return (kd->argv);
   1191 }
   1192 
   1193 char **
   1194 kvm_getargv2(kvm_t *kd, const struct kinfo_proc2 *kp, int nchr)
   1195 {
   1196 
   1197 	return (kvm_doargv2(kd, kp->p_pid, KERN_PROC_ARGV, nchr));
   1198 }
   1199 
   1200 char **
   1201 kvm_getenvv2(kvm_t *kd, const struct kinfo_proc2 *kp, int nchr)
   1202 {
   1203 
   1204 	return (kvm_doargv2(kd, kp->p_pid, KERN_PROC_ENV, nchr));
   1205 }
   1206 
   1207 /*
   1208  * Read from user space.  The user context is given by p.
   1209  */
   1210 static ssize_t
   1211 kvm_ureadm(kvm_t *kd, const struct miniproc *p, u_long uva,
   1212 	   char *buf, size_t len)
   1213 {
   1214 	char *cp;
   1215 
   1216 	cp = buf;
   1217 	while (len > 0) {
   1218 		size_t cc;
   1219 		char *dp;
   1220 		u_long cnt;
   1221 
   1222 		dp = _kvm_ureadm(kd, p, uva, &cnt);
   1223 		if (dp == NULL) {
   1224 			_kvm_err(kd, 0, "invalid address (%lx)", uva);
   1225 			return (0);
   1226 		}
   1227 		cc = (size_t)MIN(cnt, len);
   1228 		memcpy(cp, dp, cc);
   1229 		cp += cc;
   1230 		uva += cc;
   1231 		len -= cc;
   1232 	}
   1233 	return (ssize_t)(cp - buf);
   1234 }
   1235 
   1236 ssize_t
   1237 kvm_uread(kvm_t *kd, const struct proc *p, u_long uva, char *buf, size_t len)
   1238 {
   1239 	struct miniproc mp;
   1240 
   1241 	PTOMINI(p, &mp);
   1242 	return (kvm_ureadm(kd, &mp, uva, buf, len));
   1243 }
   1244