xref: /netbsd-src/sys/kern/kern_sysctl.c (revision 9fbd88883c38d0c0fbfcbe66d76fe6b0fab3f9de)
1 /*	$NetBSD: kern_sysctl.c,v 1.101 2002/01/31 00:32:47 kleink Exp $	*/
2 
3 /*-
4  * Copyright (c) 1982, 1986, 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Mike Karels at Berkeley Software Design, Inc.
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  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  *	@(#)kern_sysctl.c	8.9 (Berkeley) 5/20/95
39  */
40 
41 /*
42  * sysctl system call.
43  */
44 
45 #include <sys/cdefs.h>
46 __KERNEL_RCSID(0, "$NetBSD: kern_sysctl.c,v 1.101 2002/01/31 00:32:47 kleink Exp $");
47 
48 #include "opt_ddb.h"
49 #include "opt_insecure.h"
50 #include "opt_defcorename.h"
51 #include "opt_new_pipe.h"
52 #include "opt_sysv.h"
53 #include "pty.h"
54 
55 #include <sys/param.h>
56 #include <sys/systm.h>
57 #include <sys/kernel.h>
58 #include <sys/buf.h>
59 #include <sys/device.h>
60 #include <sys/disklabel.h>
61 #include <sys/dkstat.h>
62 #include <sys/exec.h>
63 #include <sys/file.h>
64 #include <sys/ioctl.h>
65 #include <sys/malloc.h>
66 #include <sys/mount.h>
67 #include <sys/msgbuf.h>
68 #include <sys/pool.h>
69 #include <sys/proc.h>
70 #include <sys/resource.h>
71 #include <sys/resourcevar.h>
72 #include <sys/syscallargs.h>
73 #include <sys/tty.h>
74 #include <sys/unistd.h>
75 #include <sys/vnode.h>
76 #include <sys/socketvar.h>
77 #define	__SYSCTL_PRIVATE
78 #include <sys/sysctl.h>
79 #include <sys/lock.h>
80 #include <sys/namei.h>
81 
82 #if defined(SYSVMSG) || defined(SYSVSEM) || defined(SYSVSHM)
83 #include <sys/ipc.h>
84 #endif
85 #ifdef SYSVMSG
86 #include <sys/msg.h>
87 #endif
88 #ifdef SYSVSEM
89 #include <sys/sem.h>
90 #endif
91 #ifdef SYSVSHM
92 #include <sys/shm.h>
93 #endif
94 
95 #include <dev/cons.h>
96 
97 #if defined(DDB)
98 #include <ddb/ddbvar.h>
99 #endif
100 
101 #ifdef NEW_PIPE
102 #include <sys/pipe.h>
103 #endif
104 
105 #define PTRTOINT64(foo)	((u_int64_t)(uintptr_t)(foo))
106 
107 static int sysctl_file(void *, size_t *);
108 #if defined(SYSVMSG) || defined(SYSVSEM) || defined(SYSVSHM)
109 static int sysctl_sysvipc(int *, u_int, void *, size_t *);
110 #endif
111 static int sysctl_msgbuf(void *, size_t *);
112 static int sysctl_doeproc(int *, u_int, void *, size_t *);
113 static int sysctl_dotkstat(int *, u_int, void *, size_t *, void *);
114 #ifdef MULTIPROCESSOR
115 static int sysctl_docptime(void *, size_t *, void *);
116 static int sysctl_ncpus(void);
117 #endif
118 static void fill_kproc2(struct proc *, struct kinfo_proc2 *);
119 static int sysctl_procargs(int *, u_int, void *, size_t *, struct proc *);
120 #if NPTY > 0
121 static int sysctl_pty(void *, size_t *, void *, size_t);
122 #endif
123 
124 /*
125  * The `sysctl_memlock' is intended to keep too many processes from
126  * locking down memory by doing sysctls at once.  Whether or not this
127  * is really a good idea to worry about it probably a subject of some
128  * debate.
129  */
130 struct lock sysctl_memlock;
131 
132 void
133 sysctl_init(void)
134 {
135 
136 	lockinit(&sysctl_memlock, PRIBIO|PCATCH, "sysctl", 0, 0);
137 }
138 
139 int
140 sys___sysctl(struct proc *p, void *v, register_t *retval)
141 {
142 	struct sys___sysctl_args /* {
143 		syscallarg(int *) name;
144 		syscallarg(u_int) namelen;
145 		syscallarg(void *) old;
146 		syscallarg(size_t *) oldlenp;
147 		syscallarg(void *) new;
148 		syscallarg(size_t) newlen;
149 	} */ *uap = v;
150 	int error;
151 	size_t savelen = 0, oldlen = 0;
152 	sysctlfn *fn;
153 	int name[CTL_MAXNAME];
154 	size_t *oldlenp;
155 
156 	/*
157 	 * all top-level sysctl names are non-terminal
158 	 */
159 	if (SCARG(uap, namelen) > CTL_MAXNAME || SCARG(uap, namelen) < 2)
160 		return (EINVAL);
161 	error = copyin(SCARG(uap, name), &name,
162 		       SCARG(uap, namelen) * sizeof(int));
163 	if (error)
164 		return (error);
165 
166 	/*
167 	 * For all but CTL_PROC, must be root to change a value.
168 	 * For CTL_PROC, must be root, or owner of the proc (and not suid),
169 	 * this is checked in proc_sysctl() (once we know the targer proc).
170 	 */
171 	if (SCARG(uap, new) != NULL && name[0] != CTL_PROC &&
172 		    (error = suser(p->p_ucred, &p->p_acflag)))
173 			return error;
174 
175 	switch (name[0]) {
176 	case CTL_KERN:
177 		fn = kern_sysctl;
178 		break;
179 	case CTL_HW:
180 		fn = hw_sysctl;
181 		break;
182 	case CTL_VM:
183 		fn = uvm_sysctl;
184 		break;
185 	case CTL_NET:
186 		fn = net_sysctl;
187 		break;
188 	case CTL_VFS:
189 		fn = vfs_sysctl;
190 		break;
191 	case CTL_MACHDEP:
192 		fn = cpu_sysctl;
193 		break;
194 #ifdef DEBUG
195 	case CTL_DEBUG:
196 		fn = debug_sysctl;
197 		break;
198 #endif
199 #ifdef DDB
200 	case CTL_DDB:
201 		fn = ddb_sysctl;
202 		break;
203 #endif
204 	case CTL_PROC:
205 		fn = proc_sysctl;
206 		break;
207 	default:
208 		return (EOPNOTSUPP);
209 	}
210 
211 	/*
212 	 * XXX Hey, we wire `old', but what about `new'?
213 	 */
214 
215 	oldlenp = SCARG(uap, oldlenp);
216 	if (oldlenp) {
217 		if ((error = copyin(oldlenp, &oldlen, sizeof(oldlen))))
218 			return (error);
219 		oldlenp = &oldlen;
220 	}
221 	if (SCARG(uap, old) != NULL) {
222 		error = lockmgr(&sysctl_memlock, LK_EXCLUSIVE, NULL);
223 		if (error)
224 			return (error);
225 		error = uvm_vslock(p, SCARG(uap, old), oldlen,
226 		    VM_PROT_READ|VM_PROT_WRITE);
227 		if (error) {
228 			(void) lockmgr(&sysctl_memlock, LK_RELEASE, NULL);
229 			return error;
230 		}
231 		savelen = oldlen;
232 	}
233 	error = (*fn)(name + 1, SCARG(uap, namelen) - 1, SCARG(uap, old),
234 	    oldlenp, SCARG(uap, new), SCARG(uap, newlen), p);
235 	if (SCARG(uap, old) != NULL) {
236 		uvm_vsunlock(p, SCARG(uap, old), savelen);
237 		(void) lockmgr(&sysctl_memlock, LK_RELEASE, NULL);
238 	}
239 	if (error)
240 		return (error);
241 	if (SCARG(uap, oldlenp))
242 		error = copyout(&oldlen, SCARG(uap, oldlenp), sizeof(oldlen));
243 	return (error);
244 }
245 
246 /*
247  * Attributes stored in the kernel.
248  */
249 char hostname[MAXHOSTNAMELEN];
250 int hostnamelen;
251 
252 char domainname[MAXHOSTNAMELEN];
253 int domainnamelen;
254 
255 long hostid;
256 
257 #ifdef INSECURE
258 int securelevel = -1;
259 #else
260 int securelevel = 0;
261 #endif
262 
263 #ifndef DEFCORENAME
264 #define	DEFCORENAME	"%n.core"
265 #endif
266 char defcorename[MAXPATHLEN] = DEFCORENAME;
267 int defcorenamelen = sizeof(DEFCORENAME);
268 
269 extern	int	kern_logsigexit;
270 extern	fixpt_t	ccpu;
271 
272 #ifndef MULTIPROCESSOR
273 #define sysctl_ncpus() 1
274 #endif
275 
276 #ifdef MULTIPROCESSOR
277 
278 #ifndef CPU_INFO_FOREACH
279 #define CPU_INFO_ITERATOR int
280 #define CPU_INFO_FOREACH(cii, ci) cii = 0, ci = curcpu(); ci != NULL; ci = NULL
281 #endif
282 
283 static int
284 sysctl_docptime(void *oldp, size_t *oldlenp, void *newp)
285 {
286 	u_int64_t cp_time[CPUSTATES];
287 	int i;
288 	struct cpu_info *ci;
289 	CPU_INFO_ITERATOR cii;
290 
291 	for (i=0; i<CPUSTATES; i++)
292 		cp_time[i] = 0;
293 
294 	for (CPU_INFO_FOREACH(cii, ci)) {
295 		for (i=0; i<CPUSTATES; i++)
296 			cp_time[i] += ci->ci_schedstate.spc_cp_time[i];
297 	}
298 	return (sysctl_rdstruct(oldp, oldlenp, newp,
299 	    cp_time, sizeof(cp_time)));
300 }
301 
302 static int
303 sysctl_ncpus(void)
304 {
305 	struct cpu_info *ci;
306 	CPU_INFO_ITERATOR cii;
307 
308 	int ncpus = 0;
309 	for (CPU_INFO_FOREACH(cii, ci))
310 		ncpus++;
311 	return ncpus;
312 }
313 
314 #endif
315 
316 /*
317  * kernel related system variables.
318  */
319 int
320 kern_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp,
321     void *newp, size_t newlen, struct proc *p)
322 {
323 	int error, level, inthostid;
324 	int old_autonicetime;
325 	int old_vnodes;
326 	dev_t consdev;
327 
328 	/* All sysctl names at this level, except for a few, are terminal. */
329 	switch (name[0]) {
330 	case KERN_PROC:
331 	case KERN_PROC2:
332 	case KERN_PROF:
333 	case KERN_MBUF:
334 	case KERN_PROC_ARGS:
335 	case KERN_SYSVIPC_INFO:
336 	case KERN_PIPE:
337 	case KERN_TKSTAT:
338 		/* Not terminal. */
339 		break;
340 	default:
341 		if (namelen != 1)
342 			return (ENOTDIR);	/* overloaded */
343 	}
344 
345 	switch (name[0]) {
346 	case KERN_OSTYPE:
347 		return (sysctl_rdstring(oldp, oldlenp, newp, ostype));
348 	case KERN_OSRELEASE:
349 		return (sysctl_rdstring(oldp, oldlenp, newp, osrelease));
350 	case KERN_OSREV:
351 		return (sysctl_rdint(oldp, oldlenp, newp, __NetBSD_Version__));
352 	case KERN_VERSION:
353 		return (sysctl_rdstring(oldp, oldlenp, newp, version));
354 	case KERN_MAXVNODES:
355 		old_vnodes = desiredvnodes;
356 		error = sysctl_int(oldp, oldlenp, newp, newlen, &desiredvnodes);
357 		if (newp && !error) {
358 			if (old_vnodes > desiredvnodes) {
359 				desiredvnodes = old_vnodes;
360 				return (EINVAL);
361 			}
362 			vfs_reinit();
363 			nchreinit();
364 		}
365 		return (error);
366 	case KERN_MAXPROC:
367 		return (sysctl_int(oldp, oldlenp, newp, newlen, &maxproc));
368 	case KERN_MAXFILES:
369 		return (sysctl_int(oldp, oldlenp, newp, newlen, &maxfiles));
370 	case KERN_ARGMAX:
371 		return (sysctl_rdint(oldp, oldlenp, newp, ARG_MAX));
372 	case KERN_SECURELVL:
373 		level = securelevel;
374 		if ((error = sysctl_int(oldp, oldlenp, newp, newlen, &level)) ||
375 		    newp == NULL)
376 			return (error);
377 		if (level < securelevel && p->p_pid != 1)
378 			return (EPERM);
379 		securelevel = level;
380 		return (0);
381 	case KERN_HOSTNAME:
382 		error = sysctl_string(oldp, oldlenp, newp, newlen,
383 		    hostname, sizeof(hostname));
384 		if (newp && !error)
385 			hostnamelen = newlen;
386 		return (error);
387 	case KERN_DOMAINNAME:
388 		error = sysctl_string(oldp, oldlenp, newp, newlen,
389 		    domainname, sizeof(domainname));
390 		if (newp && !error)
391 			domainnamelen = newlen;
392 		return (error);
393 	case KERN_HOSTID:
394 		inthostid = hostid;  /* XXX assumes sizeof long <= sizeof int */
395 		error =  sysctl_int(oldp, oldlenp, newp, newlen, &inthostid);
396 		if (newp && !error)
397 			hostid = inthostid;
398 		return (error);
399 	case KERN_CLOCKRATE:
400 		return (sysctl_clockrate(oldp, oldlenp));
401 	case KERN_BOOTTIME:
402 		return (sysctl_rdstruct(oldp, oldlenp, newp, &boottime,
403 		    sizeof(struct timeval)));
404 	case KERN_VNODE:
405 		return (sysctl_vnode(oldp, oldlenp, p));
406 	case KERN_PROC:
407 	case KERN_PROC2:
408 		return (sysctl_doeproc(name, namelen, oldp, oldlenp));
409 	case KERN_PROC_ARGS:
410 		return (sysctl_procargs(name + 1, namelen - 1,
411 		    oldp, oldlenp, p));
412 	case KERN_FILE:
413 		return (sysctl_file(oldp, oldlenp));
414 #ifdef GPROF
415 	case KERN_PROF:
416 		return (sysctl_doprof(name + 1, namelen - 1, oldp, oldlenp,
417 		    newp, newlen));
418 #endif
419 	case KERN_POSIX1:
420 		return (sysctl_rdint(oldp, oldlenp, newp, _POSIX_VERSION));
421 	case KERN_NGROUPS:
422 		return (sysctl_rdint(oldp, oldlenp, newp, NGROUPS_MAX));
423 	case KERN_JOB_CONTROL:
424 		return (sysctl_rdint(oldp, oldlenp, newp, 1));
425 	case KERN_SAVED_IDS:
426 #ifdef _POSIX_SAVED_IDS
427 		return (sysctl_rdint(oldp, oldlenp, newp, 1));
428 #else
429 		return (sysctl_rdint(oldp, oldlenp, newp, 0));
430 #endif
431 	case KERN_MAXPARTITIONS:
432 		return (sysctl_rdint(oldp, oldlenp, newp, MAXPARTITIONS));
433 	case KERN_RAWPARTITION:
434 		return (sysctl_rdint(oldp, oldlenp, newp, RAW_PART));
435 #ifdef NTP
436 	case KERN_NTPTIME:
437 		return (sysctl_ntptime(oldp, oldlenp));
438 #endif
439 	case KERN_AUTONICETIME:
440 	        old_autonicetime = autonicetime;
441 	        error = sysctl_int(oldp, oldlenp, newp, newlen, &autonicetime);
442 		if (autonicetime < 0)
443  		        autonicetime = old_autonicetime;
444 		return (error);
445 	case KERN_AUTONICEVAL:
446 		error = sysctl_int(oldp, oldlenp, newp, newlen, &autoniceval);
447 		if (autoniceval < PRIO_MIN)
448 			autoniceval = PRIO_MIN;
449 		if (autoniceval > PRIO_MAX)
450 			autoniceval = PRIO_MAX;
451 		return (error);
452 	case KERN_RTC_OFFSET:
453 		return (sysctl_rdint(oldp, oldlenp, newp, rtc_offset));
454 	case KERN_ROOT_DEVICE:
455 		return (sysctl_rdstring(oldp, oldlenp, newp,
456 		    root_device->dv_xname));
457 	case KERN_MSGBUFSIZE:
458 		/*
459 		 * deal with cases where the message buffer has
460 		 * become corrupted.
461 		 */
462 		if (!msgbufenabled || msgbufp->msg_magic != MSG_MAGIC) {
463 			msgbufenabled = 0;
464 			return (ENXIO);
465 		}
466 		return (sysctl_rdint(oldp, oldlenp, newp, msgbufp->msg_bufs));
467 	case KERN_FSYNC:
468 		return (sysctl_rdint(oldp, oldlenp, newp, 1));
469 	case KERN_SYSVMSG:
470 #ifdef SYSVMSG
471 		return (sysctl_rdint(oldp, oldlenp, newp, 1));
472 #else
473 		return (sysctl_rdint(oldp, oldlenp, newp, 0));
474 #endif
475 	case KERN_SYSVSEM:
476 #ifdef SYSVSEM
477 		return (sysctl_rdint(oldp, oldlenp, newp, 1));
478 #else
479 		return (sysctl_rdint(oldp, oldlenp, newp, 0));
480 #endif
481 	case KERN_SYSVSHM:
482 #ifdef SYSVSHM
483 		return (sysctl_rdint(oldp, oldlenp, newp, 1));
484 #else
485 		return (sysctl_rdint(oldp, oldlenp, newp, 0));
486 #endif
487  	case KERN_DEFCORENAME:
488 		if (newp && newlen < 1)
489 			return (EINVAL);
490 		error = sysctl_string(oldp, oldlenp, newp, newlen,
491 		    defcorename, sizeof(defcorename));
492 		if (newp && !error)
493 			defcorenamelen = newlen;
494 		return (error);
495 	case KERN_SYNCHRONIZED_IO:
496 		return (sysctl_rdint(oldp, oldlenp, newp, 1));
497 	case KERN_IOV_MAX:
498 		return (sysctl_rdint(oldp, oldlenp, newp, IOV_MAX));
499 	case KERN_MBUF:
500 		return (sysctl_dombuf(name + 1, namelen - 1, oldp, oldlenp,
501 		    newp, newlen));
502 	case KERN_MAPPED_FILES:
503 		return (sysctl_rdint(oldp, oldlenp, newp, 1));
504 	case KERN_MEMLOCK:
505 		return (sysctl_rdint(oldp, oldlenp, newp, 1));
506 	case KERN_MEMLOCK_RANGE:
507 		return (sysctl_rdint(oldp, oldlenp, newp, 1));
508 	case KERN_MEMORY_PROTECTION:
509 		return (sysctl_rdint(oldp, oldlenp, newp, 1));
510 	case KERN_LOGIN_NAME_MAX:
511 		return (sysctl_rdint(oldp, oldlenp, newp, LOGIN_NAME_MAX));
512 	case KERN_LOGSIGEXIT:
513 		return (sysctl_int(oldp, oldlenp, newp, newlen,
514 		    &kern_logsigexit));
515 	case KERN_FSCALE:
516 		return (sysctl_rdint(oldp, oldlenp, newp, FSCALE));
517 	case KERN_CCPU:
518 		return (sysctl_rdint(oldp, oldlenp, newp, ccpu));
519 	case KERN_CP_TIME:
520 #ifndef MULTIPROCESSOR
521 		return (sysctl_rdstruct(oldp, oldlenp, newp,
522 		    curcpu()->ci_schedstate.spc_cp_time,
523 		    sizeof(curcpu()->ci_schedstate.spc_cp_time)));
524 #else
525 		return (sysctl_docptime(oldp, oldlenp, newp));
526 #endif
527 #if defined(SYSVMSG) || defined(SYSVSEM) || defined(SYSVSHM)
528 	case KERN_SYSVIPC_INFO:
529 		return (sysctl_sysvipc(name + 1, namelen - 1, oldp, oldlenp));
530 #endif
531 	case KERN_MSGBUF:
532 		return (sysctl_msgbuf(oldp, oldlenp));
533 	case KERN_CONSDEV:
534 		if (cn_tab != NULL)
535 			consdev = cn_tab->cn_dev;
536 		else
537 			consdev = NODEV;
538 		return (sysctl_rdstruct(oldp, oldlenp, newp, &consdev,
539 		    sizeof consdev));
540 #if NPTY > 0
541 	case KERN_MAXPTYS:
542 		return sysctl_pty(oldp, oldlenp, newp, newlen);
543 #endif
544 #ifdef NEW_PIPE
545 	case KERN_PIPE:
546 		return (sysctl_dopipe(name + 1, namelen - 1, oldp, oldlenp,
547 		    newp, newlen));
548 #endif
549 	case KERN_MAXPHYS:
550 		return (sysctl_rdint(oldp, oldlenp, newp, MAXPHYS));
551 	case KERN_SBMAX:
552 	    {
553 		int new_sbmax = sb_max;
554 
555 		error = sysctl_int(oldp, oldlenp, newp, newlen, &new_sbmax);
556 		if (newp && !error) {
557 			if (new_sbmax < (16 * 1024)) /* sanity */
558 				return (EINVAL);
559 			sb_max = new_sbmax;
560 		}
561 		return (error);
562 	    }
563 	case KERN_TKSTAT:
564 		return (sysctl_dotkstat(name + 1, namelen - 1, oldp, oldlenp,
565 		    newp));
566 	case KERN_MONOTONIC_CLOCK:	/* XXX _POSIX_VERSION */
567 		return (sysctl_rdint(oldp, oldlenp, newp, 200112));
568 	default:
569 		return (EOPNOTSUPP);
570 	}
571 	/* NOTREACHED */
572 }
573 
574 /*
575  * hardware related system variables.
576  */
577 int
578 hw_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp,
579     void *newp, size_t newlen, struct proc *p)
580 {
581 
582 	/* All sysctl names at this level, except for a few, are terminal. */
583 	switch (name[0]) {
584 	case HW_DISKSTATS:
585 		/* Not terminal. */
586 		break;
587 	default:
588 		if (namelen != 1)
589 			return (ENOTDIR);	/* overloaded */
590 	}
591 
592 	switch (name[0]) {
593 	case HW_MACHINE:
594 		return (sysctl_rdstring(oldp, oldlenp, newp, machine));
595 	case HW_MACHINE_ARCH:
596 		return (sysctl_rdstring(oldp, oldlenp, newp, machine_arch));
597 	case HW_MODEL:
598 		return (sysctl_rdstring(oldp, oldlenp, newp, cpu_model));
599 	case HW_NCPU:
600 		return (sysctl_rdint(oldp, oldlenp, newp, sysctl_ncpus()));
601 	case HW_BYTEORDER:
602 		return (sysctl_rdint(oldp, oldlenp, newp, BYTE_ORDER));
603 	case HW_PHYSMEM:
604 		return (sysctl_rdint(oldp, oldlenp, newp, ctob(physmem)));
605 	case HW_USERMEM:
606 		return (sysctl_rdint(oldp, oldlenp, newp,
607 		    ctob(physmem - uvmexp.wired)));
608 	case HW_PAGESIZE:
609 		return (sysctl_rdint(oldp, oldlenp, newp, PAGE_SIZE));
610 	case HW_ALIGNBYTES:
611 		return (sysctl_rdint(oldp, oldlenp, newp, ALIGNBYTES));
612 	case HW_DISKNAMES:
613 		return (sysctl_disknames(oldp, oldlenp));
614 	case HW_DISKSTATS:
615 		return (sysctl_diskstats(name + 1, namelen - 1, oldp, oldlenp));
616 	case HW_CNMAGIC: {
617 		char magic[CNS_LEN];
618 		int error;
619 
620 		if (oldp)
621 			cn_get_magic(magic, CNS_LEN);
622 		error = sysctl_string(oldp, oldlenp, newp, newlen,
623 		    magic, sizeof(magic));
624 		if (newp && !error) {
625 			error = cn_set_magic(magic);
626 		}
627 		return (error);
628 	}
629 	default:
630 		return (EOPNOTSUPP);
631 	}
632 	/* NOTREACHED */
633 }
634 
635 #ifdef DEBUG
636 /*
637  * Debugging related system variables.
638  */
639 struct ctldebug debug0, debug1, debug2, debug3, debug4;
640 struct ctldebug debug5, debug6, debug7, debug8, debug9;
641 struct ctldebug debug10, debug11, debug12, debug13, debug14;
642 struct ctldebug debug15, debug16, debug17, debug18, debug19;
643 static struct ctldebug *debugvars[CTL_DEBUG_MAXID] = {
644 	&debug0, &debug1, &debug2, &debug3, &debug4,
645 	&debug5, &debug6, &debug7, &debug8, &debug9,
646 	&debug10, &debug11, &debug12, &debug13, &debug14,
647 	&debug15, &debug16, &debug17, &debug18, &debug19,
648 };
649 
650 int
651 debug_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp,
652     void *newp, size_t newlen, struct proc *p)
653 {
654 	struct ctldebug *cdp;
655 
656 	/* all sysctl names at this level are name and field */
657 	if (namelen != 2)
658 		return (ENOTDIR);		/* overloaded */
659 	cdp = debugvars[name[0]];
660 	if (name[0] >= CTL_DEBUG_MAXID || cdp->debugname == 0)
661 		return (EOPNOTSUPP);
662 	switch (name[1]) {
663 	case CTL_DEBUG_NAME:
664 		return (sysctl_rdstring(oldp, oldlenp, newp, cdp->debugname));
665 	case CTL_DEBUG_VALUE:
666 		return (sysctl_int(oldp, oldlenp, newp, newlen, cdp->debugvar));
667 	default:
668 		return (EOPNOTSUPP);
669 	}
670 	/* NOTREACHED */
671 }
672 #endif /* DEBUG */
673 
674 int
675 proc_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp,
676     void *newp, size_t newlen, struct proc *p)
677 {
678 	struct proc *ptmp = NULL;
679 	const struct proclist_desc *pd;
680 	int error = 0;
681 	struct rlimit alim;
682 	struct plimit *newplim;
683 	char *tmps = NULL;
684 	int i, curlen, len;
685 
686 	if (namelen < 2)
687 		return EINVAL;
688 
689 	if (name[0] == PROC_CURPROC) {
690 		ptmp = p;
691 	} else {
692 		proclist_lock_read();
693 		for (pd = proclists; pd->pd_list != NULL; pd++) {
694 			for (ptmp = LIST_FIRST(pd->pd_list); ptmp != NULL;
695 			    ptmp = LIST_NEXT(ptmp, p_list)) {
696 				/* Skip embryonic processes. */
697 				if (ptmp->p_stat == SIDL)
698 					continue;
699 				if (ptmp->p_pid == (pid_t)name[0])
700 					break;
701 			}
702 			if (ptmp != NULL)
703 				break;
704 		}
705 		proclist_unlock_read();
706 		if (ptmp == NULL)
707 			return(ESRCH);
708 		if (p->p_ucred->cr_uid != 0) {
709 			if(p->p_cred->p_ruid != ptmp->p_cred->p_ruid ||
710 			    p->p_cred->p_ruid != ptmp->p_cred->p_svuid)
711 				return EPERM;
712 			if (ptmp->p_cred->p_rgid != ptmp->p_cred->p_svgid)
713 				return EPERM; /* sgid proc */
714 			for (i = 0; i < p->p_ucred->cr_ngroups; i++) {
715 				if (p->p_ucred->cr_groups[i] ==
716 				    ptmp->p_cred->p_rgid)
717 					break;
718 			}
719 			if (i == p->p_ucred->cr_ngroups)
720 				return EPERM;
721 		}
722 	}
723 	if (name[1] == PROC_PID_CORENAME) {
724 		if (namelen != 2)
725 			return EINVAL;
726 		/*
727 		 * Can't use sysctl_string() here because we may malloc a new
728 		 * area during the process, so we have to do it by hand.
729 		 */
730 		curlen = strlen(ptmp->p_limit->pl_corename) + 1;
731 		if (oldlenp  && *oldlenp < curlen) {
732 			if (!oldp)
733 				*oldlenp = curlen;
734 			return (ENOMEM);
735 		}
736 		if (newp) {
737 			if (securelevel > 2)
738 				return EPERM;
739 			if (newlen > MAXPATHLEN)
740 				return ENAMETOOLONG;
741 			tmps = malloc(newlen + 1, M_TEMP, M_WAITOK);
742 			if (tmps == NULL)
743 				return ENOMEM;
744 			error = copyin(newp, tmps, newlen + 1);
745 			tmps[newlen] = '\0';
746 			if (error)
747 				goto cleanup;
748 			/* Enforce to be either 'core' for end with '.core' */
749 			if (newlen < 4)  { /* c.o.r.e */
750 				error = EINVAL;
751 				goto cleanup;
752 			}
753 			len = newlen - 4;
754 			if (len > 0) {
755 				if (tmps[len - 1] != '.' &&
756 				    tmps[len - 1] != '/') {
757 					error = EINVAL;
758 					goto cleanup;
759 				}
760 			}
761 			if (strcmp(&tmps[len], "core") != 0) {
762 				error = EINVAL;
763 				goto cleanup;
764 			}
765 		}
766 		if (oldp && oldlenp) {
767 			*oldlenp = curlen;
768 			error = copyout(ptmp->p_limit->pl_corename, oldp,
769 			    curlen);
770 		}
771 		if (newp && error == 0) {
772 			/* if the 2 strings are identical, don't limcopy() */
773 			if (strcmp(tmps, ptmp->p_limit->pl_corename) == 0) {
774 				error = 0;
775 				goto cleanup;
776 			}
777 			if (ptmp->p_limit->p_refcnt > 1 &&
778 			    (ptmp->p_limit->p_lflags & PL_SHAREMOD) == 0) {
779 				newplim = limcopy(ptmp->p_limit);
780 				limfree(ptmp->p_limit);
781 				ptmp->p_limit = newplim;
782 			}
783 			if (ptmp->p_limit->pl_corename != defcorename) {
784 				free(ptmp->p_limit->pl_corename, M_TEMP);
785 			}
786 			ptmp->p_limit->pl_corename = tmps;
787 			return (0);
788 		}
789 cleanup:
790 		if (tmps)
791 			free(tmps, M_TEMP);
792 		return (error);
793 	}
794 	if (name[1] == PROC_PID_LIMIT) {
795 		if (namelen != 4 || name[2] >= PROC_PID_LIMIT_MAXID)
796 			return EINVAL;
797 		memcpy(&alim, &ptmp->p_rlimit[name[2] - 1], sizeof(alim));
798 		if (name[3] == PROC_PID_LIMIT_TYPE_HARD)
799 			error = sysctl_quad(oldp, oldlenp, newp, newlen,
800 			    &alim.rlim_max);
801 		else if (name[3] == PROC_PID_LIMIT_TYPE_SOFT)
802 			error = sysctl_quad(oldp, oldlenp, newp, newlen,
803 			    &alim.rlim_cur);
804 		else
805 			error = EINVAL;
806 
807 		if (error)
808 			return error;
809 
810 		if (newp)
811 			error = dosetrlimit(ptmp, p->p_cred,
812 			    name[2] - 1, &alim);
813 		return error;
814 	}
815 	return (EINVAL);
816 }
817 
818 /*
819  * Convenience macros.
820  */
821 
822 #define SYSCTL_SCALAR_CORE_LEN(oldp, oldlenp, valp, len) 		\
823 	if (oldlenp) {							\
824 		if (!oldp)						\
825 			*oldlenp = len;					\
826 		else {							\
827 			if (*oldlenp < len)				\
828 				return(ENOMEM);				\
829 			*oldlenp = len;					\
830 			error = copyout((caddr_t)valp, oldp, len);	\
831 		}							\
832 	}
833 
834 #define SYSCTL_SCALAR_CORE_TYP(oldp, oldlenp, valp, typ) \
835 	SYSCTL_SCALAR_CORE_LEN(oldp, oldlenp, valp, sizeof(typ))
836 
837 #define SYSCTL_SCALAR_NEWPCHECK_LEN(newp, newlen, len)	\
838 	if (newp && newlen != len)			\
839 		return (EINVAL);
840 
841 #define SYSCTL_SCALAR_NEWPCHECK_TYP(newp, newlen, typ)	\
842 	SYSCTL_SCALAR_NEWPCHECK_LEN(newp, newlen, sizeof(typ))
843 
844 #define SYSCTL_SCALAR_NEWPCOP_LEN(newp, valp, len)	\
845 	if (error == 0 && newp)				\
846 		error = copyin(newp, valp, len);
847 
848 #define SYSCTL_SCALAR_NEWPCOP_TYP(newp, valp, typ)      \
849 	SYSCTL_SCALAR_NEWPCOP_LEN(newp, valp, sizeof(typ))
850 
851 #define SYSCTL_STRING_CORE(oldp, oldlenp, str)		\
852 	if (oldlenp) {					\
853 		len = strlen(str) + 1;			\
854 		if (!oldp)				\
855 			*oldlenp = len;			\
856 		else {					\
857 			if (*oldlenp < len) {		\
858 				err2 = ENOMEM;		\
859 				len = *oldlenp;		\
860 			} else				\
861 				*oldlenp = len;		\
862 			error = copyout(str, oldp, len);\
863 			if (error == 0)			\
864 				error = err2;		\
865 		}					\
866 	}
867 
868 /*
869  * Validate parameters and get old / set new parameters
870  * for an integer-valued sysctl function.
871  */
872 int
873 sysctl_int(void *oldp, size_t *oldlenp, void *newp, size_t newlen, int *valp)
874 {
875 	int error = 0;
876 
877 	SYSCTL_SCALAR_NEWPCHECK_TYP(newp, newlen, int)
878 	SYSCTL_SCALAR_CORE_TYP(oldp, oldlenp, valp, int)
879 	SYSCTL_SCALAR_NEWPCOP_TYP(newp, valp, int)
880 
881 	return (error);
882 }
883 
884 
885 /*
886  * As above, but read-only.
887  */
888 int
889 sysctl_rdint(void *oldp, size_t *oldlenp, void *newp, int val)
890 {
891 	int error = 0;
892 
893 	if (newp)
894 		return (EPERM);
895 
896 	SYSCTL_SCALAR_CORE_TYP(oldp, oldlenp, &val, int)
897 
898 	return (error);
899 }
900 
901 /*
902  * Validate parameters and get old / set new parameters
903  * for an quad-valued sysctl function.
904  */
905 int
906 sysctl_quad(void *oldp, size_t *oldlenp, void *newp, size_t newlen,
907     quad_t *valp)
908 {
909 	int error = 0;
910 
911 	SYSCTL_SCALAR_NEWPCHECK_TYP(newp, newlen, quad_t)
912 	SYSCTL_SCALAR_CORE_TYP(oldp, oldlenp, valp, quad_t)
913 	SYSCTL_SCALAR_NEWPCOP_TYP(newp, valp, quad_t)
914 
915 	return (error);
916 }
917 
918 /*
919  * As above, but read-only.
920  */
921 int
922 sysctl_rdquad(void *oldp, size_t *oldlenp, void *newp, quad_t val)
923 {
924 	int error = 0;
925 
926 	if (newp)
927 		return (EPERM);
928 
929 	SYSCTL_SCALAR_CORE_TYP(oldp, oldlenp, &val, quad_t)
930 
931 	return (error);
932 }
933 
934 /*
935  * Validate parameters and get old / set new parameters
936  * for a string-valued sysctl function.
937  */
938 int
939 sysctl_string(void *oldp, size_t *oldlenp, void *newp, size_t newlen, char *str,
940     int maxlen)
941 {
942 	int len, error = 0, err2 = 0;
943 
944 	if (newp && newlen >= maxlen)
945 		return (EINVAL);
946 
947 	SYSCTL_STRING_CORE(oldp, oldlenp, str);
948 
949 	if (error == 0 && newp) {
950 		error = copyin(newp, str, newlen);
951 		str[newlen] = 0;
952 	}
953 	return (error);
954 }
955 
956 /*
957  * As above, but read-only.
958  */
959 int
960 sysctl_rdstring(void *oldp, size_t *oldlenp, void *newp, const char *str)
961 {
962 	int len, error = 0, err2 = 0;
963 
964 	if (newp)
965 		return (EPERM);
966 
967 	SYSCTL_STRING_CORE(oldp, oldlenp, str);
968 
969 	return (error);
970 }
971 
972 /*
973  * Validate parameters and get old / set new parameters
974  * for a structure oriented sysctl function.
975  */
976 int
977 sysctl_struct(void *oldp, size_t *oldlenp, void *newp, size_t newlen, void *sp,
978     int len)
979 {
980 	int error = 0;
981 
982 	SYSCTL_SCALAR_NEWPCHECK_LEN(newp, newlen, len)
983 	SYSCTL_SCALAR_CORE_LEN(oldp, oldlenp, sp, len)
984 	SYSCTL_SCALAR_NEWPCOP_LEN(newp, sp, len)
985 
986 	return (error);
987 }
988 
989 /*
990  * Validate parameters and get old parameters
991  * for a structure oriented sysctl function.
992  */
993 int
994 sysctl_rdstruct(void *oldp, size_t *oldlenp, void *newp, const void *sp,
995     int len)
996 {
997 	int error = 0;
998 
999 	if (newp)
1000 		return (EPERM);
1001 
1002 	SYSCTL_SCALAR_CORE_LEN(oldp, oldlenp, sp, len)
1003 
1004 	return (error);
1005 }
1006 
1007 /*
1008  * As above, but can return a truncated result.
1009  */
1010 int
1011 sysctl_rdminstruct(void *oldp, size_t *oldlenp, void *newp, const void *sp,
1012     int len)
1013 {
1014 	int error = 0;
1015 
1016 	if (newp)
1017 		return (EPERM);
1018 
1019 	len = min(*oldlenp, len);
1020 	SYSCTL_SCALAR_CORE_LEN(oldp, oldlenp, sp, len)
1021 
1022 	return (error);
1023 }
1024 
1025 /*
1026  * Get file structures.
1027  */
1028 static int
1029 sysctl_file(void *vwhere, size_t *sizep)
1030 {
1031 	int buflen, error;
1032 	struct file *fp;
1033 	char *start, *where;
1034 
1035 	start = where = vwhere;
1036 	buflen = *sizep;
1037 	if (where == NULL) {
1038 		/*
1039 		 * overestimate by 10 files
1040 		 */
1041 		*sizep = sizeof(filehead) + (nfiles + 10) * sizeof(struct file);
1042 		return (0);
1043 	}
1044 
1045 	/*
1046 	 * first copyout filehead
1047 	 */
1048 	if (buflen < sizeof(filehead)) {
1049 		*sizep = 0;
1050 		return (0);
1051 	}
1052 	error = copyout((caddr_t)&filehead, where, sizeof(filehead));
1053 	if (error)
1054 		return (error);
1055 	buflen -= sizeof(filehead);
1056 	where += sizeof(filehead);
1057 
1058 	/*
1059 	 * followed by an array of file structures
1060 	 */
1061 	for (fp = filehead.lh_first; fp != 0; fp = fp->f_list.le_next) {
1062 		if (buflen < sizeof(struct file)) {
1063 			*sizep = where - start;
1064 			return (ENOMEM);
1065 		}
1066 		error = copyout((caddr_t)fp, where, sizeof(struct file));
1067 		if (error)
1068 			return (error);
1069 		buflen -= sizeof(struct file);
1070 		where += sizeof(struct file);
1071 	}
1072 	*sizep = where - start;
1073 	return (0);
1074 }
1075 
1076 #if defined(SYSVMSG) || defined(SYSVSEM) || defined(SYSVSHM)
1077 #define	FILL_PERM(src, dst) do { \
1078 		(dst)._key = (src)._key; \
1079 		(dst).uid = (src).uid; \
1080 		(dst).gid = (src).gid; \
1081 		(dst).cuid = (src).cuid; \
1082 		(dst).cgid = (src).cgid; \
1083 		(dst).mode = (src).mode; \
1084 		(dst)._seq = (src)._seq; \
1085 	} while (0);
1086 #define	FILL_MSG(src, dst) do { \
1087 	FILL_PERM((src).msg_perm, (dst).msg_perm); \
1088 	(dst).msg_qnum = (src).msg_qnum; \
1089 	(dst).msg_qbytes = (src).msg_qbytes; \
1090 	(dst)._msg_cbytes = (src)._msg_cbytes; \
1091 	(dst).msg_lspid = (src).msg_lspid; \
1092 	(dst).msg_lrpid = (src).msg_lrpid; \
1093 	(dst).msg_stime = (src).msg_stime; \
1094 	(dst).msg_rtime = (src).msg_rtime; \
1095 	(dst).msg_ctime = (src).msg_ctime; \
1096 	} while (0)
1097 #define	FILL_SEM(src, dst) do { \
1098 	FILL_PERM((src).sem_perm, (dst).sem_perm); \
1099 	(dst).sem_nsems = (src).sem_nsems; \
1100 	(dst).sem_otime = (src).sem_otime; \
1101 	(dst).sem_ctime = (src).sem_ctime; \
1102 	} while (0)
1103 #define	FILL_SHM(src, dst) do { \
1104 	FILL_PERM((src).shm_perm, (dst).shm_perm); \
1105 	(dst).shm_segsz = (src).shm_segsz; \
1106 	(dst).shm_lpid = (src).shm_lpid; \
1107 	(dst).shm_cpid = (src).shm_cpid; \
1108 	(dst).shm_atime = (src).shm_atime; \
1109 	(dst).shm_dtime = (src).shm_dtime; \
1110 	(dst).shm_ctime = (src).shm_ctime; \
1111 	(dst).shm_nattch = (src).shm_nattch; \
1112 	} while (0)
1113 
1114 static int
1115 sysctl_sysvipc(int *name, u_int namelen, void *where, size_t *sizep)
1116 {
1117 #ifdef SYSVMSG
1118 	struct msg_sysctl_info *msgsi;
1119 #endif
1120 #ifdef SYSVSEM
1121 	struct sem_sysctl_info *semsi;
1122 #endif
1123 #ifdef SYSVSHM
1124 	struct shm_sysctl_info *shmsi;
1125 #endif
1126 	size_t infosize, dssize, tsize, buflen;
1127 	void *buf = NULL, *buf2;
1128 	char *start;
1129 	int32_t nds;
1130 	int i, error, ret;
1131 
1132 	if (namelen != 1)
1133 		return (EINVAL);
1134 
1135 	start = where;
1136 	buflen = *sizep;
1137 
1138 	switch (*name) {
1139 	case KERN_SYSVIPC_MSG_INFO:
1140 #ifdef SYSVMSG
1141 		infosize = sizeof(msgsi->msginfo);
1142 		nds = msginfo.msgmni;
1143 		dssize = sizeof(msgsi->msgids[0]);
1144 		break;
1145 #else
1146 		return (EINVAL);
1147 #endif
1148 	case KERN_SYSVIPC_SEM_INFO:
1149 #ifdef SYSVSEM
1150 		infosize = sizeof(semsi->seminfo);
1151 		nds = seminfo.semmni;
1152 		dssize = sizeof(semsi->semids[0]);
1153 		break;
1154 #else
1155 		return (EINVAL);
1156 #endif
1157 	case KERN_SYSVIPC_SHM_INFO:
1158 #ifdef SYSVSHM
1159 		infosize = sizeof(shmsi->shminfo);
1160 		nds = shminfo.shmmni;
1161 		dssize = sizeof(shmsi->shmids[0]);
1162 		break;
1163 #else
1164 		return (EINVAL);
1165 #endif
1166 	default:
1167 		return (EINVAL);
1168 	}
1169 	/*
1170 	 * Round infosize to 64 bit boundary if requesting more than just
1171 	 * the info structure or getting the total data size.
1172 	 */
1173 	if (where == NULL || *sizep > infosize)
1174 		infosize = ((infosize + 7) / 8) * 8;
1175 	tsize = infosize + nds * dssize;
1176 
1177 	/* Return just the total size required. */
1178 	if (where == NULL) {
1179 		*sizep = tsize;
1180 		return (0);
1181 	}
1182 
1183 	/* Not enough room for even the info struct. */
1184 	if (buflen < infosize) {
1185 		*sizep = 0;
1186 		return (ENOMEM);
1187 	}
1188 	buf = malloc(min(tsize, buflen), M_TEMP, M_WAITOK);
1189 	memset(buf, 0, min(tsize, buflen));
1190 
1191 	switch (*name) {
1192 #ifdef SYSVMSG
1193 	case KERN_SYSVIPC_MSG_INFO:
1194 		msgsi = (struct msg_sysctl_info *)buf;
1195 		buf2 = &msgsi->msgids[0];
1196 		msgsi->msginfo = msginfo;
1197 		break;
1198 #endif
1199 #ifdef SYSVSEM
1200 	case KERN_SYSVIPC_SEM_INFO:
1201 		semsi = (struct sem_sysctl_info *)buf;
1202 		buf2 = &semsi->semids[0];
1203 		semsi->seminfo = seminfo;
1204 		break;
1205 #endif
1206 #ifdef SYSVSHM
1207 	case KERN_SYSVIPC_SHM_INFO:
1208 		shmsi = (struct shm_sysctl_info *)buf;
1209 		buf2 = &shmsi->shmids[0];
1210 		shmsi->shminfo = shminfo;
1211 		break;
1212 #endif
1213 	}
1214 	buflen -= infosize;
1215 
1216 	ret = 0;
1217 	if (buflen > 0) {
1218 		/* Fill in the IPC data structures.  */
1219 		for (i = 0; i < nds; i++) {
1220 			if (buflen < dssize) {
1221 				ret = ENOMEM;
1222 				break;
1223 			}
1224 			switch (*name) {
1225 #ifdef SYSVMSG
1226 			case KERN_SYSVIPC_MSG_INFO:
1227 				FILL_MSG(msqids[i], msgsi->msgids[i]);
1228 				break;
1229 #endif
1230 #ifdef SYSVSEM
1231 			case KERN_SYSVIPC_SEM_INFO:
1232 				FILL_SEM(sema[i], semsi->semids[i]);
1233 				break;
1234 #endif
1235 #ifdef SYSVSHM
1236 			case KERN_SYSVIPC_SHM_INFO:
1237 				FILL_SHM(shmsegs[i], shmsi->shmids[i]);
1238 				break;
1239 #endif
1240 			}
1241 			buflen -= dssize;
1242 		}
1243 	}
1244 	*sizep -= buflen;
1245 	error = copyout(buf, start, *sizep);
1246 	/* If copyout succeeded, use return code set earlier. */
1247 	if (error == 0)
1248 		error = ret;
1249 	if (buf)
1250 		free(buf, M_TEMP);
1251 	return (error);
1252 }
1253 #endif /* SYSVMSG || SYSVSEM || SYSVSHM */
1254 
1255 static int
1256 sysctl_msgbuf(void *vwhere, size_t *sizep)
1257 {
1258 	char *where = vwhere;
1259 	size_t len, maxlen = *sizep;
1260 	long beg, end;
1261 	int error;
1262 
1263 	/*
1264 	 * deal with cases where the message buffer has
1265 	 * become corrupted.
1266 	 */
1267 	if (!msgbufenabled || msgbufp->msg_magic != MSG_MAGIC) {
1268 		msgbufenabled = 0;
1269 		return (ENXIO);
1270 	}
1271 
1272 	if (where == NULL) {
1273 		/* always return full buffer size */
1274 		*sizep = msgbufp->msg_bufs;
1275 		return (0);
1276 	}
1277 
1278 	error = 0;
1279 	maxlen = min(msgbufp->msg_bufs, maxlen);
1280 
1281 	/*
1282 	 * First, copy from the write pointer to the end of
1283 	 * message buffer.
1284 	 */
1285 	beg = msgbufp->msg_bufx;
1286 	end = msgbufp->msg_bufs;
1287 	while (maxlen > 0) {
1288 		len = min(end - beg, maxlen);
1289 		if (len == 0)
1290 			break;
1291 		error = copyout(&msgbufp->msg_bufc[beg], where, len);
1292 		if (error)
1293 			break;
1294 		where += len;
1295 		maxlen -= len;
1296 
1297 		/*
1298 		 * ... then, copy from the beginning of message buffer to
1299 		 * the write pointer.
1300 		 */
1301 		beg = 0;
1302 		end = msgbufp->msg_bufx;
1303 	}
1304 	return (error);
1305 }
1306 
1307 /*
1308  * try over estimating by 5 procs
1309  */
1310 #define KERN_PROCSLOP	(5 * sizeof(struct kinfo_proc))
1311 
1312 static int
1313 sysctl_doeproc(int *name, u_int namelen, void *vwhere, size_t *sizep)
1314 {
1315 	struct eproc eproc;
1316 	struct kinfo_proc2 kproc2;
1317 	struct kinfo_proc *dp;
1318 	struct proc *p;
1319 	const struct proclist_desc *pd;
1320 	char *where, *dp2;
1321 	int type, op, arg, elem_size, elem_count;
1322 	int buflen, needed, error;
1323 
1324 	dp = vwhere;
1325 	dp2 = where = vwhere;
1326 	buflen = where != NULL ? *sizep : 0;
1327 	error = needed = 0;
1328 	type = name[0];
1329 
1330 	if (type == KERN_PROC) {
1331 		if (namelen != 3 && !(namelen == 2 && name[1] == KERN_PROC_ALL))
1332 			return (EINVAL);
1333 		op = name[1];
1334 		if (op != KERN_PROC_ALL)
1335 			arg = name[2];
1336 	} else {
1337 		if (namelen != 5)
1338 			return (EINVAL);
1339 		op = name[1];
1340 		arg = name[2];
1341 		elem_size = name[3];
1342 		elem_count = name[4];
1343 	}
1344 
1345 	proclist_lock_read();
1346 
1347 	pd = proclists;
1348 again:
1349 	for (p = LIST_FIRST(pd->pd_list); p != NULL; p = LIST_NEXT(p, p_list)) {
1350 		/*
1351 		 * Skip embryonic processes.
1352 		 */
1353 		if (p->p_stat == SIDL)
1354 			continue;
1355 		/*
1356 		 * TODO - make more efficient (see notes below).
1357 		 * do by session.
1358 		 */
1359 		switch (op) {
1360 
1361 		case KERN_PROC_PID:
1362 			/* could do this with just a lookup */
1363 			if (p->p_pid != (pid_t)arg)
1364 				continue;
1365 			break;
1366 
1367 		case KERN_PROC_PGRP:
1368 			/* could do this by traversing pgrp */
1369 			if (p->p_pgrp->pg_id != (pid_t)arg)
1370 				continue;
1371 			break;
1372 
1373 		case KERN_PROC_SESSION:
1374 			if (p->p_session->s_sid != (pid_t)arg)
1375 				continue;
1376 			break;
1377 
1378 		case KERN_PROC_TTY:
1379 			if (arg == KERN_PROC_TTY_REVOKE) {
1380 				if ((p->p_flag & P_CONTROLT) == 0 ||
1381 				    p->p_session->s_ttyp == NULL ||
1382 				    p->p_session->s_ttyvp != NULL)
1383 					continue;
1384 			} else if ((p->p_flag & P_CONTROLT) == 0 ||
1385 			    p->p_session->s_ttyp == NULL) {
1386 				if ((dev_t)arg != KERN_PROC_TTY_NODEV)
1387 					continue;
1388 			} else if (p->p_session->s_ttyp->t_dev != (dev_t)arg)
1389 				continue;
1390 			break;
1391 
1392 		case KERN_PROC_UID:
1393 			if (p->p_ucred->cr_uid != (uid_t)arg)
1394 				continue;
1395 			break;
1396 
1397 		case KERN_PROC_RUID:
1398 			if (p->p_cred->p_ruid != (uid_t)arg)
1399 				continue;
1400 			break;
1401 
1402 		case KERN_PROC_GID:
1403 			if (p->p_ucred->cr_gid != (uid_t)arg)
1404 				continue;
1405 			break;
1406 
1407 		case KERN_PROC_RGID:
1408 			if (p->p_cred->p_rgid != (uid_t)arg)
1409 				continue;
1410 			break;
1411 
1412 		case KERN_PROC_ALL:
1413 			/* allow everything */
1414 			break;
1415 
1416 		default:
1417 			error = EINVAL;
1418 			goto cleanup;
1419 		}
1420 		if (type == KERN_PROC) {
1421 			if (buflen >= sizeof(struct kinfo_proc)) {
1422 				fill_eproc(p, &eproc);
1423 				error = copyout((caddr_t)p, &dp->kp_proc,
1424 						sizeof(struct proc));
1425 				if (error)
1426 					goto cleanup;
1427 				error = copyout((caddr_t)&eproc, &dp->kp_eproc,
1428 						sizeof(eproc));
1429 				if (error)
1430 					goto cleanup;
1431 				dp++;
1432 				buflen -= sizeof(struct kinfo_proc);
1433 			}
1434 			needed += sizeof(struct kinfo_proc);
1435 		} else { /* KERN_PROC2 */
1436 			if (buflen >= elem_size && elem_count > 0) {
1437 				fill_kproc2(p, &kproc2);
1438 				/*
1439 				 * Copy out elem_size, but not larger than
1440 				 * the size of a struct kinfo_proc2.
1441 				 */
1442 				error = copyout(&kproc2, dp2,
1443 				    min(sizeof(kproc2), elem_size));
1444 				if (error)
1445 					goto cleanup;
1446 				dp2 += elem_size;
1447 				buflen -= elem_size;
1448 				elem_count--;
1449 			}
1450 			needed += elem_size;
1451 		}
1452 	}
1453 	pd++;
1454 	if (pd->pd_list != NULL)
1455 		goto again;
1456 	proclist_unlock_read();
1457 
1458 	if (where != NULL) {
1459 		if (type == KERN_PROC)
1460 			*sizep = (caddr_t)dp - where;
1461 		else
1462 			*sizep = dp2 - where;
1463 		if (needed > *sizep)
1464 			return (ENOMEM);
1465 	} else {
1466 		needed += KERN_PROCSLOP;
1467 		*sizep = needed;
1468 	}
1469 	return (0);
1470  cleanup:
1471 	proclist_unlock_read();
1472 	return (error);
1473 }
1474 
1475 /*
1476  * Fill in an eproc structure for the specified process.
1477  */
1478 void
1479 fill_eproc(struct proc *p, struct eproc *ep)
1480 {
1481 	struct tty *tp;
1482 
1483 	ep->e_paddr = p;
1484 	ep->e_sess = p->p_session;
1485 	ep->e_pcred = *p->p_cred;
1486 	ep->e_ucred = *p->p_ucred;
1487 	if (p->p_stat == SIDL || P_ZOMBIE(p)) {
1488 		ep->e_vm.vm_rssize = 0;
1489 		ep->e_vm.vm_tsize = 0;
1490 		ep->e_vm.vm_dsize = 0;
1491 		ep->e_vm.vm_ssize = 0;
1492 		/* ep->e_vm.vm_pmap = XXX; */
1493 	} else {
1494 		struct vmspace *vm = p->p_vmspace;
1495 
1496 		ep->e_vm.vm_rssize = vm_resident_count(vm);
1497 		ep->e_vm.vm_tsize = vm->vm_tsize;
1498 		ep->e_vm.vm_dsize = vm->vm_dsize;
1499 		ep->e_vm.vm_ssize = vm->vm_ssize;
1500 	}
1501 	if (p->p_pptr)
1502 		ep->e_ppid = p->p_pptr->p_pid;
1503 	else
1504 		ep->e_ppid = 0;
1505 	ep->e_pgid = p->p_pgrp->pg_id;
1506 	ep->e_sid = ep->e_sess->s_sid;
1507 	ep->e_jobc = p->p_pgrp->pg_jobc;
1508 	if ((p->p_flag & P_CONTROLT) &&
1509 	     (tp = ep->e_sess->s_ttyp)) {
1510 		ep->e_tdev = tp->t_dev;
1511 		ep->e_tpgid = tp->t_pgrp ? tp->t_pgrp->pg_id : NO_PID;
1512 		ep->e_tsess = tp->t_session;
1513 	} else
1514 		ep->e_tdev = NODEV;
1515 	if (p->p_wmesg)
1516 		strncpy(ep->e_wmesg, p->p_wmesg, WMESGLEN);
1517 	ep->e_xsize = ep->e_xrssize = 0;
1518 	ep->e_xccount = ep->e_xswrss = 0;
1519 	ep->e_flag = ep->e_sess->s_ttyvp ? EPROC_CTTY : 0;
1520 	if (SESS_LEADER(p))
1521 		ep->e_flag |= EPROC_SLEADER;
1522 	strncpy(ep->e_login, ep->e_sess->s_login, MAXLOGNAME);
1523 }
1524 
1525 /*
1526  * Fill in an eproc structure for the specified process.
1527  */
1528 static void
1529 fill_kproc2(struct proc *p, struct kinfo_proc2 *ki)
1530 {
1531 	struct tty *tp;
1532 
1533 	memset(ki, 0, sizeof(*ki));
1534 
1535 	ki->p_forw = PTRTOINT64(p->p_forw);
1536 	ki->p_back = PTRTOINT64(p->p_back);
1537 	ki->p_paddr = PTRTOINT64(p);
1538 
1539 	ki->p_addr = PTRTOINT64(p->p_addr);
1540 	ki->p_fd = PTRTOINT64(p->p_fd);
1541 	ki->p_cwdi = PTRTOINT64(p->p_cwdi);
1542 	ki->p_stats = PTRTOINT64(p->p_stats);
1543 	ki->p_limit = PTRTOINT64(p->p_limit);
1544 	ki->p_vmspace = PTRTOINT64(p->p_vmspace);
1545 	ki->p_sigacts = PTRTOINT64(p->p_sigacts);
1546 	ki->p_sess = PTRTOINT64(p->p_session);
1547 	ki->p_tsess = 0;	/* may be changed if controlling tty below */
1548 	ki->p_ru = PTRTOINT64(p->p_ru);
1549 
1550 	ki->p_eflag = 0;
1551 	ki->p_exitsig = p->p_exitsig;
1552 	ki->p_flag = p->p_flag;
1553 
1554 	ki->p_pid = p->p_pid;
1555 	if (p->p_pptr)
1556 		ki->p_ppid = p->p_pptr->p_pid;
1557 	else
1558 		ki->p_ppid = 0;
1559 	ki->p_sid = p->p_session->s_sid;
1560 	ki->p__pgid = p->p_pgrp->pg_id;
1561 
1562 	ki->p_tpgid = NO_PID;	/* may be changed if controlling tty below */
1563 
1564 	ki->p_uid = p->p_ucred->cr_uid;
1565 	ki->p_ruid = p->p_cred->p_ruid;
1566 	ki->p_gid = p->p_ucred->cr_gid;
1567 	ki->p_rgid = p->p_cred->p_rgid;
1568 
1569 	memcpy(ki->p_groups, p->p_cred->pc_ucred->cr_groups,
1570 	    min(sizeof(ki->p_groups), sizeof(p->p_cred->pc_ucred->cr_groups)));
1571 	ki->p_ngroups = p->p_cred->pc_ucred->cr_ngroups;
1572 
1573 	ki->p_jobc = p->p_pgrp->pg_jobc;
1574 	if ((p->p_flag & P_CONTROLT) && (tp = p->p_session->s_ttyp)) {
1575 		ki->p_tdev = tp->t_dev;
1576 		ki->p_tpgid = tp->t_pgrp ? tp->t_pgrp->pg_id : NO_PID;
1577 		ki->p_tsess = PTRTOINT64(tp->t_session);
1578 	} else {
1579 		ki->p_tdev = NODEV;
1580 	}
1581 
1582 	ki->p_estcpu = p->p_estcpu;
1583 	ki->p_rtime_sec = p->p_rtime.tv_sec;
1584 	ki->p_rtime_usec = p->p_rtime.tv_usec;
1585 	ki->p_cpticks = p->p_cpticks;
1586 	ki->p_pctcpu = p->p_pctcpu;
1587 	ki->p_swtime = p->p_swtime;
1588 	ki->p_slptime = p->p_slptime;
1589 	if (p->p_stat == SONPROC) {
1590 		KDASSERT(p->p_cpu != NULL);
1591 		ki->p_schedflags = p->p_cpu->ci_schedstate.spc_flags;
1592 	} else
1593 		ki->p_schedflags = 0;
1594 
1595 	ki->p_uticks = p->p_uticks;
1596 	ki->p_sticks = p->p_sticks;
1597 	ki->p_iticks = p->p_iticks;
1598 
1599 	ki->p_tracep = PTRTOINT64(p->p_tracep);
1600 	ki->p_traceflag = p->p_traceflag;
1601 
1602 	ki->p_holdcnt = p->p_holdcnt;
1603 
1604 	memcpy(&ki->p_siglist, &p->p_sigctx.ps_siglist, sizeof(ki_sigset_t));
1605 	memcpy(&ki->p_sigmask, &p->p_sigctx.ps_sigmask, sizeof(ki_sigset_t));
1606 	memcpy(&ki->p_sigignore, &p->p_sigctx.ps_sigignore,sizeof(ki_sigset_t));
1607 	memcpy(&ki->p_sigcatch, &p->p_sigctx.ps_sigcatch, sizeof(ki_sigset_t));
1608 
1609 	ki->p_stat = p->p_stat;
1610 	ki->p_priority = p->p_priority;
1611 	ki->p_usrpri = p->p_usrpri;
1612 	ki->p_nice = p->p_nice;
1613 
1614 	ki->p_xstat = p->p_xstat;
1615 	ki->p_acflag = p->p_acflag;
1616 
1617 	strncpy(ki->p_comm, p->p_comm,
1618 	    min(sizeof(ki->p_comm), sizeof(p->p_comm)));
1619 
1620 	if (p->p_wmesg)
1621 		strncpy(ki->p_wmesg, p->p_wmesg, sizeof(ki->p_wmesg));
1622 	ki->p_wchan = PTRTOINT64(p->p_wchan);
1623 
1624 	strncpy(ki->p_login, p->p_session->s_login, sizeof(ki->p_login));
1625 
1626 	if (p->p_stat == SIDL || P_ZOMBIE(p)) {
1627 		ki->p_vm_rssize = 0;
1628 		ki->p_vm_tsize = 0;
1629 		ki->p_vm_dsize = 0;
1630 		ki->p_vm_ssize = 0;
1631 	} else {
1632 		struct vmspace *vm = p->p_vmspace;
1633 
1634 		ki->p_vm_rssize = vm_resident_count(vm);
1635 		ki->p_vm_tsize = vm->vm_tsize;
1636 		ki->p_vm_dsize = vm->vm_dsize;
1637 		ki->p_vm_ssize = vm->vm_ssize;
1638 	}
1639 
1640 	if (p->p_session->s_ttyvp)
1641 		ki->p_eflag |= EPROC_CTTY;
1642 	if (SESS_LEADER(p))
1643 		ki->p_eflag |= EPROC_SLEADER;
1644 
1645 	/* XXX Is this double check necessary? */
1646 	if ((p->p_flag & P_INMEM) == 0 || P_ZOMBIE(p)) {
1647 		ki->p_uvalid = 0;
1648 	} else {
1649 		ki->p_uvalid = 1;
1650 
1651 		ki->p_ustart_sec = p->p_stats->p_start.tv_sec;
1652 		ki->p_ustart_usec = p->p_stats->p_start.tv_usec;
1653 
1654 		ki->p_uutime_sec = p->p_stats->p_ru.ru_utime.tv_sec;
1655 		ki->p_uutime_usec = p->p_stats->p_ru.ru_utime.tv_usec;
1656 		ki->p_ustime_sec = p->p_stats->p_ru.ru_stime.tv_sec;
1657 		ki->p_ustime_usec = p->p_stats->p_ru.ru_stime.tv_usec;
1658 
1659 		ki->p_uru_maxrss = p->p_stats->p_ru.ru_maxrss;
1660 		ki->p_uru_ixrss = p->p_stats->p_ru.ru_ixrss;
1661 		ki->p_uru_idrss = p->p_stats->p_ru.ru_idrss;
1662 		ki->p_uru_isrss = p->p_stats->p_ru.ru_isrss;
1663 		ki->p_uru_minflt = p->p_stats->p_ru.ru_minflt;
1664 		ki->p_uru_majflt = p->p_stats->p_ru.ru_majflt;
1665 		ki->p_uru_nswap = p->p_stats->p_ru.ru_nswap;
1666 		ki->p_uru_inblock = p->p_stats->p_ru.ru_inblock;
1667 		ki->p_uru_oublock = p->p_stats->p_ru.ru_oublock;
1668 		ki->p_uru_msgsnd = p->p_stats->p_ru.ru_msgsnd;
1669 		ki->p_uru_msgrcv = p->p_stats->p_ru.ru_msgrcv;
1670 		ki->p_uru_nsignals = p->p_stats->p_ru.ru_nsignals;
1671 		ki->p_uru_nvcsw = p->p_stats->p_ru.ru_nvcsw;
1672 		ki->p_uru_nivcsw = p->p_stats->p_ru.ru_nivcsw;
1673 
1674 		ki->p_uctime_sec = p->p_stats->p_cru.ru_utime.tv_sec +
1675 		    p->p_stats->p_cru.ru_stime.tv_sec;
1676 		ki->p_uctime_usec = p->p_stats->p_cru.ru_utime.tv_usec +
1677 		    p->p_stats->p_cru.ru_stime.tv_usec;
1678 	}
1679 #ifdef MULTIPROCESSOR
1680 	if (p->p_cpu != NULL)
1681 		ki->p_cpuid = p->p_cpu->ci_cpuid;
1682 	else
1683 #endif
1684 		ki->p_cpuid = KI_NOCPU;
1685 }
1686 
1687 int
1688 sysctl_procargs(int *name, u_int namelen, void *where, size_t *sizep,
1689     struct proc *up)
1690 {
1691 	struct ps_strings pss;
1692 	struct proc *p;
1693 	size_t len, upper_bound, xlen;
1694 	struct uio auio;
1695 	struct iovec aiov;
1696 	vaddr_t argv;
1697 	pid_t pid;
1698 	int nargv, type, error, i;
1699 	char *arg;
1700 	char *tmp;
1701 
1702 	if (namelen != 2)
1703 		return (EINVAL);
1704 	pid = name[0];
1705 	type = name[1];
1706 
1707 	switch (type) {
1708 	  case KERN_PROC_ARGV:
1709 	  case KERN_PROC_NARGV:
1710 	  case KERN_PROC_ENV:
1711 	  case KERN_PROC_NENV:
1712 		/* ok */
1713 		break;
1714 	  default:
1715 		return (EINVAL);
1716 	}
1717 
1718 	/* check pid */
1719 	if ((p = pfind(pid)) == NULL)
1720 		return (EINVAL);
1721 
1722 	/* only root or same user change look at the environment */
1723 	if (type == KERN_PROC_ENV || type == KERN_PROC_NENV) {
1724 		if (up->p_ucred->cr_uid != 0) {
1725 			if (up->p_cred->p_ruid != p->p_cred->p_ruid ||
1726 			    up->p_cred->p_ruid != p->p_cred->p_svuid)
1727 				return (EPERM);
1728 		}
1729 	}
1730 
1731 	if (sizep != NULL && where == NULL) {
1732 		if (type == KERN_PROC_NARGV || type == KERN_PROC_NENV)
1733 			*sizep = sizeof (int);
1734 		else
1735 			*sizep = ARG_MAX;	/* XXX XXX XXX */
1736 		return (0);
1737 	}
1738 	if (where == NULL || sizep == NULL)
1739 		return (EINVAL);
1740 
1741 	/*
1742 	 * Zombies don't have a stack, so we can't read their psstrings.
1743 	 * System processes also don't have a user stack.
1744 	 */
1745 	if (P_ZOMBIE(p) || (p->p_flag & P_SYSTEM) != 0)
1746 		return (EINVAL);
1747 
1748 	/*
1749 	 * Lock the process down in memory.
1750 	 */
1751 	/* XXXCDC: how should locking work here? */
1752 	if ((p->p_flag & P_WEXIT) || (p->p_vmspace->vm_refcnt < 1))
1753 		return (EFAULT);
1754 	p->p_vmspace->vm_refcnt++;	/* XXX */
1755 
1756 	/*
1757 	 * Allocate a temporary buffer to hold the arguments.
1758 	 */
1759 	arg = malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
1760 
1761 	/*
1762 	 * Read in the ps_strings structure.
1763 	 */
1764 	aiov.iov_base = &pss;
1765 	aiov.iov_len = sizeof(pss);
1766 	auio.uio_iov = &aiov;
1767 	auio.uio_iovcnt = 1;
1768 	auio.uio_offset = (vaddr_t)p->p_psstr;
1769 	auio.uio_resid = sizeof(pss);
1770 	auio.uio_segflg = UIO_SYSSPACE;
1771 	auio.uio_rw = UIO_READ;
1772 	auio.uio_procp = NULL;
1773 	error = uvm_io(&p->p_vmspace->vm_map, &auio);
1774 	if (error)
1775 		goto done;
1776 
1777 	if (type == KERN_PROC_ARGV || type == KERN_PROC_NARGV)
1778 		memcpy(&nargv, (char *)&pss + p->p_psnargv, sizeof(nargv));
1779 	else
1780 		memcpy(&nargv, (char *)&pss + p->p_psnenv, sizeof(nargv));
1781 	if (type == KERN_PROC_NARGV || type == KERN_PROC_NENV) {
1782 		error = copyout(&nargv, where, sizeof(nargv));
1783 		*sizep = sizeof(nargv);
1784 		goto done;
1785 	}
1786 	/*
1787 	 * Now read the address of the argument vector.
1788 	 */
1789 	switch (type) {
1790 	case KERN_PROC_ARGV:
1791 		/* XXX compat32 stuff here */
1792 		memcpy(&tmp, (char *)&pss + p->p_psargv, sizeof(tmp));
1793 		break;
1794 	case KERN_PROC_ENV:
1795 		memcpy(&tmp, (char *)&pss + p->p_psenv, sizeof(tmp));
1796 		break;
1797 	default:
1798 		return (EINVAL);
1799 	}
1800 	auio.uio_offset = (off_t)(long)tmp;
1801 	aiov.iov_base = &argv;
1802 	aiov.iov_len = sizeof(argv);
1803 	auio.uio_iov = &aiov;
1804 	auio.uio_iovcnt = 1;
1805 	auio.uio_resid = sizeof(argv);
1806 	auio.uio_segflg = UIO_SYSSPACE;
1807 	auio.uio_rw = UIO_READ;
1808 	auio.uio_procp = NULL;
1809 	error = uvm_io(&p->p_vmspace->vm_map, &auio);
1810 	if (error)
1811 		goto done;
1812 
1813 	/*
1814 	 * Now copy in the actual argument vector, one page at a time,
1815 	 * since we don't know how long the vector is (though, we do
1816 	 * know how many NUL-terminated strings are in the vector).
1817 	 */
1818 	len = 0;
1819 	upper_bound = *sizep;
1820 	for (; nargv != 0 && len < upper_bound; len += xlen) {
1821 		aiov.iov_base = arg;
1822 		aiov.iov_len = PAGE_SIZE;
1823 		auio.uio_iov = &aiov;
1824 		auio.uio_iovcnt = 1;
1825 		auio.uio_offset = argv + len;
1826 		xlen = PAGE_SIZE - ((argv + len) & PAGE_MASK);
1827 		auio.uio_resid = xlen;
1828 		auio.uio_segflg = UIO_SYSSPACE;
1829 		auio.uio_rw = UIO_READ;
1830 		auio.uio_procp = NULL;
1831 		error = uvm_io(&p->p_vmspace->vm_map, &auio);
1832 		if (error)
1833 			goto done;
1834 
1835 		for (i = 0; i < xlen && nargv != 0; i++) {
1836 			if (arg[i] == '\0')
1837 				nargv--;	/* one full string */
1838 		}
1839 
1840 		/* make sure we don't copyout past the end of the user's buffer */
1841 		if (len + i > upper_bound)
1842 			i = upper_bound - len;
1843 
1844 		error = copyout(arg, (char *)where + len, i);
1845 		if (error)
1846 			break;
1847 
1848 		if (nargv == 0) {
1849 			len += i;
1850 			break;
1851 		}
1852 	}
1853 	*sizep = len;
1854 
1855 done:
1856 	uvmspace_free(p->p_vmspace);
1857 
1858 	free(arg, M_TEMP);
1859 	return (error);
1860 }
1861 
1862 #if NPTY > 0
1863 int pty_maxptys(int, int);		/* defined in kern/tty_pty.c */
1864 
1865 /*
1866  * Validate parameters and get old / set new parameters
1867  * for pty sysctl function.
1868  */
1869 static int
1870 sysctl_pty(void *oldp, size_t *oldlenp, void *newp, size_t newlen)
1871 {
1872 	int error = 0;
1873 	int oldmax = 0, newmax = 0;
1874 
1875 	/* get current value of maxptys */
1876 	oldmax = pty_maxptys(0, 0);
1877 
1878 	SYSCTL_SCALAR_CORE_TYP(oldp, oldlenp, &oldmax, int)
1879 
1880 	if (!error && newp) {
1881 		SYSCTL_SCALAR_NEWPCHECK_TYP(newp, newlen, int)
1882 		SYSCTL_SCALAR_NEWPCOP_TYP(newp, &newmax, int)
1883 
1884 		if (newmax != pty_maxptys(newmax, (newp != NULL)))
1885 			return (EINVAL);
1886 
1887 	}
1888 
1889 	return (error);
1890 }
1891 #endif /* NPTY > 0 */
1892 
1893 static int
1894 sysctl_dotkstat(name, namelen, where, sizep, newp)
1895 	int *name;
1896 	u_int namelen;
1897 	void *where;
1898 	size_t *sizep;
1899 	void *newp;
1900 {
1901 	/* all sysctl names at this level are terminal */
1902 	if (namelen != 1)
1903 		return (ENOTDIR);		/* overloaded */
1904 
1905 	switch (name[0]) {
1906 	case KERN_TKSTAT_NIN:
1907 		return (sysctl_rdquad(where, sizep, newp, tk_nin));
1908 	case KERN_TKSTAT_NOUT:
1909 		return (sysctl_rdquad(where, sizep, newp, tk_nout));
1910 	case KERN_TKSTAT_CANCC:
1911 		return (sysctl_rdquad(where, sizep, newp, tk_cancc));
1912 	case KERN_TKSTAT_RAWCC:
1913 		return (sysctl_rdquad(where, sizep, newp, tk_rawcc));
1914 	default:
1915 		return (EOPNOTSUPP);
1916 	}
1917 }
1918