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kern_resource.c revision 1.74
      1 /*	$NetBSD: kern_resource.c,v 1.74 2003/12/04 19:38:23 atatat Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1982, 1986, 1991, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  * (c) UNIX System Laboratories, Inc.
      7  * All or some portions of this file are derived from material licensed
      8  * to the University of California by American Telephone and Telegraph
      9  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
     10  * the permission of UNIX System Laboratories, Inc.
     11  *
     12  * Redistribution and use in source and binary forms, with or without
     13  * modification, are permitted provided that the following conditions
     14  * are met:
     15  * 1. Redistributions of source code must retain the above copyright
     16  *    notice, this list of conditions and the following disclaimer.
     17  * 2. Redistributions in binary form must reproduce the above copyright
     18  *    notice, this list of conditions and the following disclaimer in the
     19  *    documentation and/or other materials provided with the distribution.
     20  * 3. Neither the name of the University nor the names of its contributors
     21  *    may be used to endorse or promote products derived from this software
     22  *    without specific prior written permission.
     23  *
     24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     34  * SUCH DAMAGE.
     35  *
     36  *	@(#)kern_resource.c	8.8 (Berkeley) 2/14/95
     37  */
     38 
     39 #include <sys/cdefs.h>
     40 __KERNEL_RCSID(0, "$NetBSD: kern_resource.c,v 1.74 2003/12/04 19:38:23 atatat Exp $");
     41 
     42 #include <sys/param.h>
     43 #include <sys/systm.h>
     44 #include <sys/kernel.h>
     45 #include <sys/file.h>
     46 #include <sys/resourcevar.h>
     47 #include <sys/malloc.h>
     48 #include <sys/pool.h>
     49 #include <sys/proc.h>
     50 #include <sys/sysctl.h>
     51 
     52 #include <sys/mount.h>
     53 #include <sys/sa.h>
     54 #include <sys/syscallargs.h>
     55 
     56 #include <uvm/uvm_extern.h>
     57 
     58 /*
     59  * Maximum process data and stack limits.
     60  * They are variables so they are patchable.
     61  *
     62  * XXXX Do we really need them to be patchable?
     63  */
     64 rlim_t maxdmap = MAXDSIZ;
     65 rlim_t maxsmap = MAXSSIZ;
     66 
     67 /*
     68  * Resource controls and accounting.
     69  */
     70 
     71 int
     72 sys_getpriority(l, v, retval)
     73 	struct lwp *l;
     74 	void *v;
     75 	register_t *retval;
     76 {
     77 	struct sys_getpriority_args /* {
     78 		syscallarg(int) which;
     79 		syscallarg(int) who;
     80 	} */ *uap = v;
     81 	struct proc *curp = l->l_proc, *p;
     82 	int low = NZERO + PRIO_MAX + 1;
     83 
     84 	switch (SCARG(uap, which)) {
     85 
     86 	case PRIO_PROCESS:
     87 		if (SCARG(uap, who) == 0)
     88 			p = curp;
     89 		else
     90 			p = pfind(SCARG(uap, who));
     91 		if (p == 0)
     92 			break;
     93 		low = p->p_nice;
     94 		break;
     95 
     96 	case PRIO_PGRP: {
     97 		struct pgrp *pg;
     98 
     99 		if (SCARG(uap, who) == 0)
    100 			pg = curp->p_pgrp;
    101 		else if ((pg = pgfind(SCARG(uap, who))) == NULL)
    102 			break;
    103 		LIST_FOREACH(p, &pg->pg_members, p_pglist) {
    104 			if (p->p_nice < low)
    105 				low = p->p_nice;
    106 		}
    107 		break;
    108 	}
    109 
    110 	case PRIO_USER:
    111 		if (SCARG(uap, who) == 0)
    112 			SCARG(uap, who) = curp->p_ucred->cr_uid;
    113 		proclist_lock_read();
    114 		LIST_FOREACH(p, &allproc, p_list) {
    115 			if (p->p_ucred->cr_uid == (uid_t) SCARG(uap, who) &&
    116 			    p->p_nice < low)
    117 				low = p->p_nice;
    118 		}
    119 		proclist_unlock_read();
    120 		break;
    121 
    122 	default:
    123 		return (EINVAL);
    124 	}
    125 	if (low == NZERO + PRIO_MAX + 1)
    126 		return (ESRCH);
    127 	*retval = low - NZERO;
    128 	return (0);
    129 }
    130 
    131 /* ARGSUSED */
    132 int
    133 sys_setpriority(l, v, retval)
    134 	struct lwp *l;
    135 	void *v;
    136 	register_t *retval;
    137 {
    138 	struct sys_setpriority_args /* {
    139 		syscallarg(int) which;
    140 		syscallarg(int) who;
    141 		syscallarg(int) prio;
    142 	} */ *uap = v;
    143 	struct proc *curp = l->l_proc, *p;
    144 	int found = 0, error = 0;
    145 
    146 	switch (SCARG(uap, which)) {
    147 
    148 	case PRIO_PROCESS:
    149 		if (SCARG(uap, who) == 0)
    150 			p = curp;
    151 		else
    152 			p = pfind(SCARG(uap, who));
    153 		if (p == 0)
    154 			break;
    155 		error = donice(curp, p, SCARG(uap, prio));
    156 		found++;
    157 		break;
    158 
    159 	case PRIO_PGRP: {
    160 		struct pgrp *pg;
    161 
    162 		if (SCARG(uap, who) == 0)
    163 			pg = curp->p_pgrp;
    164 		else if ((pg = pgfind(SCARG(uap, who))) == NULL)
    165 			break;
    166 		LIST_FOREACH(p, &pg->pg_members, p_pglist) {
    167 			error = donice(curp, p, SCARG(uap, prio));
    168 			found++;
    169 		}
    170 		break;
    171 	}
    172 
    173 	case PRIO_USER:
    174 		if (SCARG(uap, who) == 0)
    175 			SCARG(uap, who) = curp->p_ucred->cr_uid;
    176 		proclist_lock_read();
    177 		LIST_FOREACH(p, &allproc, p_list) {
    178 			if (p->p_ucred->cr_uid == (uid_t) SCARG(uap, who)) {
    179 				error = donice(curp, p, SCARG(uap, prio));
    180 				found++;
    181 			}
    182 		}
    183 		proclist_unlock_read();
    184 		break;
    185 
    186 	default:
    187 		return (EINVAL);
    188 	}
    189 	if (found == 0)
    190 		return (ESRCH);
    191 	return (error);
    192 }
    193 
    194 int
    195 donice(curp, chgp, n)
    196 	struct proc *curp, *chgp;
    197 	int n;
    198 {
    199 	struct pcred *pcred = curp->p_cred;
    200 	int s;
    201 
    202 	if (pcred->pc_ucred->cr_uid && pcred->p_ruid &&
    203 	    pcred->pc_ucred->cr_uid != chgp->p_ucred->cr_uid &&
    204 	    pcred->p_ruid != chgp->p_ucred->cr_uid)
    205 		return (EPERM);
    206 	if (n > PRIO_MAX)
    207 		n = PRIO_MAX;
    208 	if (n < PRIO_MIN)
    209 		n = PRIO_MIN;
    210 	n += NZERO;
    211 	if (n < chgp->p_nice && suser(pcred->pc_ucred, &curp->p_acflag))
    212 		return (EACCES);
    213 	chgp->p_nice = n;
    214 	SCHED_LOCK(s);
    215 	(void)resetprocpriority(chgp);
    216 	SCHED_UNLOCK(s);
    217 	return (0);
    218 }
    219 
    220 /* ARGSUSED */
    221 int
    222 sys_setrlimit(l, v, retval)
    223 	struct lwp *l;
    224 	void *v;
    225 	register_t *retval;
    226 {
    227 	struct sys_setrlimit_args /* {
    228 		syscallarg(int) which;
    229 		syscallarg(const struct rlimit *) rlp;
    230 	} */ *uap = v;
    231 	struct proc *p = l->l_proc;
    232 	int which = SCARG(uap, which);
    233 	struct rlimit alim;
    234 	int error;
    235 
    236 	error = copyin(SCARG(uap, rlp), &alim, sizeof(struct rlimit));
    237 	if (error)
    238 		return (error);
    239 	return (dosetrlimit(p, p->p_cred, which, &alim));
    240 }
    241 
    242 int
    243 dosetrlimit(p, cred, which, limp)
    244 	struct proc *p;
    245 	struct  pcred *cred;
    246 	int which;
    247 	struct rlimit *limp;
    248 {
    249 	struct rlimit *alimp;
    250 	struct plimit *newplim;
    251 	int error;
    252 
    253 	if ((u_int)which >= RLIM_NLIMITS)
    254 		return (EINVAL);
    255 
    256 	if (limp->rlim_cur < 0 || limp->rlim_max < 0)
    257 		return (EINVAL);
    258 
    259 	alimp = &p->p_rlimit[which];
    260 	/* if we don't change the value, no need to limcopy() */
    261 	if (limp->rlim_cur == alimp->rlim_cur &&
    262 	    limp->rlim_max == alimp->rlim_max)
    263 		return 0;
    264 
    265 	if (limp->rlim_cur > limp->rlim_max) {
    266 		/*
    267 		 * This is programming error. According to SUSv2, we should
    268 		 * return error in this case.
    269 		 */
    270 		return (EINVAL);
    271 	}
    272 	if (limp->rlim_max > alimp->rlim_max
    273 	    && (error = suser(cred->pc_ucred, &p->p_acflag)) != 0)
    274 			return (error);
    275 
    276 	if (p->p_limit->p_refcnt > 1 &&
    277 	    (p->p_limit->p_lflags & PL_SHAREMOD) == 0) {
    278 		newplim = limcopy(p->p_limit);
    279 		limfree(p->p_limit);
    280 		p->p_limit = newplim;
    281 		alimp = &p->p_rlimit[which];
    282 	}
    283 
    284 	switch (which) {
    285 
    286 	case RLIMIT_DATA:
    287 		if (limp->rlim_cur > maxdmap)
    288 			limp->rlim_cur = maxdmap;
    289 		if (limp->rlim_max > maxdmap)
    290 			limp->rlim_max = maxdmap;
    291 		break;
    292 
    293 	case RLIMIT_STACK:
    294 		if (limp->rlim_cur > maxsmap)
    295 			limp->rlim_cur = maxsmap;
    296 		if (limp->rlim_max > maxsmap)
    297 			limp->rlim_max = maxsmap;
    298 
    299 		/*
    300 		 * Return EINVAL if the new stack size limit is lower than
    301 		 * current usage. Otherwise, the process would get SIGSEGV the
    302 		 * moment it would try to access anything on it's current stack.
    303 		 * This conforms to SUSv2.
    304 		 */
    305 		if (limp->rlim_cur < p->p_vmspace->vm_ssize * PAGE_SIZE
    306 		    || limp->rlim_max < p->p_vmspace->vm_ssize * PAGE_SIZE)
    307 			return (EINVAL);
    308 
    309 		/*
    310 		 * Stack is allocated to the max at exec time with
    311 		 * only "rlim_cur" bytes accessible (In other words,
    312 		 * allocates stack dividing two contiguous regions at
    313 		 * "rlim_cur" bytes boundary).
    314 		 *
    315 		 * Since allocation is done in terms of page, roundup
    316 		 * "rlim_cur" (otherwise, contiguous regions
    317 		 * overlap).  If stack limit is going up make more
    318 		 * accessible, if going down make inaccessible.
    319 		 */
    320 		limp->rlim_cur = round_page(limp->rlim_cur);
    321 		if (limp->rlim_cur != alimp->rlim_cur) {
    322 			vaddr_t addr;
    323 			vsize_t size;
    324 			vm_prot_t prot;
    325 
    326 			if (limp->rlim_cur > alimp->rlim_cur) {
    327 				prot = VM_PROT_READ | VM_PROT_WRITE;
    328 				size = limp->rlim_cur - alimp->rlim_cur;
    329 				addr = USRSTACK - limp->rlim_cur;
    330 			} else {
    331 				prot = VM_PROT_NONE;
    332 				size = alimp->rlim_cur - limp->rlim_cur;
    333 				addr = USRSTACK - alimp->rlim_cur;
    334 			}
    335 			(void) uvm_map_protect(&p->p_vmspace->vm_map,
    336 					      addr, addr+size, prot, FALSE);
    337 		}
    338 		break;
    339 
    340 	case RLIMIT_NOFILE:
    341 		if (limp->rlim_cur > maxfiles)
    342 			limp->rlim_cur = maxfiles;
    343 		if (limp->rlim_max > maxfiles)
    344 			limp->rlim_max = maxfiles;
    345 		break;
    346 
    347 	case RLIMIT_NPROC:
    348 		if (limp->rlim_cur > maxproc)
    349 			limp->rlim_cur = maxproc;
    350 		if (limp->rlim_max > maxproc)
    351 			limp->rlim_max = maxproc;
    352 		break;
    353 	}
    354 	*alimp = *limp;
    355 	return (0);
    356 }
    357 
    358 /* ARGSUSED */
    359 int
    360 sys_getrlimit(l, v, retval)
    361 	struct lwp *l;
    362 	void *v;
    363 	register_t *retval;
    364 {
    365 	struct sys_getrlimit_args /* {
    366 		syscallarg(int) which;
    367 		syscallarg(struct rlimit *) rlp;
    368 	} */ *uap = v;
    369 	struct proc *p = l->l_proc;
    370 	int which = SCARG(uap, which);
    371 
    372 	if ((u_int)which >= RLIM_NLIMITS)
    373 		return (EINVAL);
    374 	return (copyout(&p->p_rlimit[which], SCARG(uap, rlp),
    375 	    sizeof(struct rlimit)));
    376 }
    377 
    378 /*
    379  * Transform the running time and tick information in proc p into user,
    380  * system, and interrupt time usage.
    381  */
    382 void
    383 calcru(p, up, sp, ip)
    384 	struct proc *p;
    385 	struct timeval *up;
    386 	struct timeval *sp;
    387 	struct timeval *ip;
    388 {
    389 	u_quad_t u, st, ut, it, tot;
    390 	unsigned long sec;
    391 	long usec;
    392 	int s;
    393 	struct timeval tv;
    394 	struct lwp *l;
    395 
    396 	s = splstatclock();
    397 	st = p->p_sticks;
    398 	ut = p->p_uticks;
    399 	it = p->p_iticks;
    400 	splx(s);
    401 
    402 	sec = p->p_rtime.tv_sec;
    403 	usec = p->p_rtime.tv_usec;
    404 	LIST_FOREACH(l, &p->p_lwps, l_sibling) {
    405 		if (l->l_stat == LSONPROC) {
    406 			struct schedstate_percpu *spc;
    407 
    408 			KDASSERT(l->l_cpu != NULL);
    409 			spc = &l->l_cpu->ci_schedstate;
    410 
    411 			/*
    412 			 * Adjust for the current time slice.  This is
    413 			 * actually fairly important since the error
    414 			 * here is on the order of a time quantum,
    415 			 * which is much greater than the sampling
    416 			 * error.
    417 			 */
    418 			microtime(&tv);
    419 			sec += tv.tv_sec - spc->spc_runtime.tv_sec;
    420 			usec += tv.tv_usec - spc->spc_runtime.tv_usec;
    421 		}
    422 	}
    423 
    424 	tot = st + ut + it;
    425 	u = sec * 1000000ull + usec;
    426 
    427 	if (tot == 0) {
    428 		/* No ticks, so can't use to share time out, split 50-50 */
    429 		st = ut = u / 2;
    430 	} else {
    431 		st = (u * st) / tot;
    432 		ut = (u * ut) / tot;
    433 	}
    434 	sp->tv_sec = st / 1000000;
    435 	sp->tv_usec = st % 1000000;
    436 	up->tv_sec = ut / 1000000;
    437 	up->tv_usec = ut % 1000000;
    438 	if (ip != NULL) {
    439 		if (it != 0)
    440 			it = (u * it) / tot;
    441 		ip->tv_sec = it / 1000000;
    442 		ip->tv_usec = it % 1000000;
    443 	}
    444 }
    445 
    446 /* ARGSUSED */
    447 int
    448 sys_getrusage(l, v, retval)
    449 	struct lwp *l;
    450 	void *v;
    451 	register_t *retval;
    452 {
    453 	struct sys_getrusage_args /* {
    454 		syscallarg(int) who;
    455 		syscallarg(struct rusage *) rusage;
    456 	} */ *uap = v;
    457 	struct rusage *rup;
    458 	struct proc *p = l->l_proc;
    459 
    460 	switch (SCARG(uap, who)) {
    461 
    462 	case RUSAGE_SELF:
    463 		rup = &p->p_stats->p_ru;
    464 		calcru(p, &rup->ru_utime, &rup->ru_stime, NULL);
    465 		break;
    466 
    467 	case RUSAGE_CHILDREN:
    468 		rup = &p->p_stats->p_cru;
    469 		break;
    470 
    471 	default:
    472 		return (EINVAL);
    473 	}
    474 	return (copyout(rup, SCARG(uap, rusage), sizeof(struct rusage)));
    475 }
    476 
    477 void
    478 ruadd(ru, ru2)
    479 	struct rusage *ru, *ru2;
    480 {
    481 	long *ip, *ip2;
    482 	int i;
    483 
    484 	timeradd(&ru->ru_utime, &ru2->ru_utime, &ru->ru_utime);
    485 	timeradd(&ru->ru_stime, &ru2->ru_stime, &ru->ru_stime);
    486 	if (ru->ru_maxrss < ru2->ru_maxrss)
    487 		ru->ru_maxrss = ru2->ru_maxrss;
    488 	ip = &ru->ru_first; ip2 = &ru2->ru_first;
    489 	for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--)
    490 		*ip++ += *ip2++;
    491 }
    492 
    493 /*
    494  * Make a copy of the plimit structure.
    495  * We share these structures copy-on-write after fork,
    496  * and copy when a limit is changed.
    497  */
    498 struct plimit *
    499 limcopy(lim)
    500 	struct plimit *lim;
    501 {
    502 	struct plimit *newlim;
    503 	size_t l;
    504 
    505 	newlim = pool_get(&plimit_pool, PR_WAITOK);
    506 	memcpy(newlim->pl_rlimit, lim->pl_rlimit,
    507 	    sizeof(struct rlimit) * RLIM_NLIMITS);
    508 	if (lim->pl_corename == defcorename) {
    509 		newlim->pl_corename = defcorename;
    510 	} else {
    511 		l = strlen(lim->pl_corename) + 1;
    512 		newlim->pl_corename = malloc(l, M_TEMP, M_WAITOK);
    513 		strlcpy(newlim->pl_corename, lim->pl_corename, l);
    514 	}
    515 	newlim->p_lflags = 0;
    516 	newlim->p_refcnt = 1;
    517 	return (newlim);
    518 }
    519 
    520 void
    521 limfree(lim)
    522 	struct plimit *lim;
    523 {
    524 
    525 	if (--lim->p_refcnt > 0)
    526 		return;
    527 #ifdef DIAGNOSTIC
    528 	if (lim->p_refcnt < 0)
    529 		panic("limfree");
    530 #endif
    531 	if (lim->pl_corename != defcorename)
    532 		free(lim->pl_corename, M_TEMP);
    533 	pool_put(&plimit_pool, lim);
    534 }
    535 
    536 struct pstats *
    537 pstatscopy(ps)
    538 	struct pstats *ps;
    539 {
    540 
    541 	struct pstats *newps;
    542 
    543 	newps = pool_get(&pstats_pool, PR_WAITOK);
    544 
    545 	memset(&newps->pstat_startzero, 0,
    546 	(unsigned) ((caddr_t)&newps->pstat_endzero -
    547 		    (caddr_t)&newps->pstat_startzero));
    548 	memcpy(&newps->pstat_startcopy, &ps->pstat_startcopy,
    549 	((caddr_t)&newps->pstat_endcopy -
    550 	 (caddr_t)&newps->pstat_startcopy));
    551 
    552 	return (newps);
    553 
    554 }
    555 
    556 void
    557 pstatsfree(ps)
    558 	struct pstats *ps;
    559 {
    560 
    561 	pool_put(&pstats_pool, ps);
    562 }
    563 
    564 /*
    565  * sysctl interface in five parts
    566  */
    567 
    568 /*
    569  * a routine for sysctl proc subtree helpers that need to pick a valid
    570  * process by pid.
    571  */
    572 static int
    573 sysctl_proc_findproc(struct proc *p, struct proc **p2, pid_t pid)
    574 {
    575 	struct proc *ptmp;
    576 	int i, error = 0;
    577 
    578 	if (pid == PROC_CURPROC)
    579 		ptmp = p;
    580 	else if ((ptmp = pfind(pid)) == NULL)
    581 		error = ESRCH;
    582 	else {
    583 		/*
    584 		 * suid proc of ours or proc not ours
    585 		 */
    586 		if (p->p_cred->p_ruid != ptmp->p_cred->p_ruid ||
    587 		    p->p_cred->p_ruid != ptmp->p_cred->p_svuid)
    588 			error = suser(p->p_ucred, &p->p_acflag);
    589 
    590 		/*
    591 		 * sgid proc has sgid back to us temporarily
    592 		 */
    593 		else if (ptmp->p_cred->p_rgid != ptmp->p_cred->p_svgid)
    594 			error = suser(p->p_ucred, &p->p_acflag);
    595 
    596 		/*
    597 		 * our rgid must be in target's group list (ie,
    598 		 * sub-processes started by a sgid process)
    599 		 */
    600 		else {
    601 			for (i = 0; i < p->p_ucred->cr_ngroups; i++) {
    602 				if (p->p_ucred->cr_groups[i] ==
    603 				    ptmp->p_cred->p_rgid)
    604 					break;
    605 			}
    606 			if (i == p->p_ucred->cr_ngroups)
    607 				error = suser(p->p_ucred, &p->p_acflag);
    608 		}
    609 	}
    610 
    611 	*p2 = ptmp;
    612 	return (error);
    613 }
    614 
    615 /*
    616  * sysctl helper routine for setting a process's specific corefile
    617  * name.  picks the process based on the given pid and checks the
    618  * correctness of the new value.
    619  */
    620 static int
    621 sysctl_proc_corename(SYSCTLFN_ARGS)
    622 {
    623 	struct proc *ptmp, *p;
    624 	struct plimit *newplim;
    625 	int error = 0, len;
    626 	char cname[MAXPATHLEN], *tmp;
    627 	struct sysctlnode node;
    628 
    629 	/*
    630 	 * is this all correct?
    631 	 */
    632 	if (namelen != 0)
    633 		return (EINVAL);
    634 	if (name[-1] != PROC_PID_CORENAME)
    635 		return (EINVAL);
    636 
    637 	/*
    638 	 * whom are we tweaking?
    639 	 */
    640 	p = l->l_proc;
    641 	error = sysctl_proc_findproc(p, &ptmp, (pid_t)name[-2]);
    642 	if (error)
    643 		return (error);
    644 
    645 	/*
    646 	 * let them modify a temporary copy of the core name
    647 	 */
    648 	node = *rnode;
    649 	strlcpy(cname, ptmp->p_limit->pl_corename, sizeof(cname));
    650 	node.sysctl_data = cname;
    651 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
    652 
    653 	/*
    654 	 * if that failed, or they have nothing new to say, or we've
    655 	 * heard it before...
    656 	 */
    657 	if (error || newp == NULL ||
    658 	    strcmp(cname, ptmp->p_limit->pl_corename) == 0)
    659 		return (error);
    660 
    661 	/*
    662 	 * no error yet and cname now has the new core name in it.
    663 	 * let's see if it looks acceptable.  it must be either "core"
    664 	 * or end in ".core" or "/core".
    665 	 */
    666 	len = strlen(cname);
    667 	if (len < 4)
    668 		return (EINVAL);
    669 	if (strcmp(cname + len - 4, "core") != 0)
    670 		return (EINVAL);
    671 	if (len > 4 && cname[len - 5] != '/' && cname[len - 5] != '.')
    672 		return (EINVAL);
    673 
    674 	/*
    675 	 * hmm...looks good.  now...where do we put it?
    676 	 */
    677 	tmp = malloc(len + 1, M_TEMP, M_WAITOK|M_CANFAIL);
    678 	if (tmp == NULL)
    679 		return (ENOMEM);
    680 	strlcpy(tmp, cname, len + 1);
    681 
    682 	if (ptmp->p_limit->p_refcnt > 1 &&
    683 	    (ptmp->p_limit->p_lflags & PL_SHAREMOD) == 0) {
    684 		newplim = limcopy(ptmp->p_limit);
    685 		limfree(ptmp->p_limit);
    686 		ptmp->p_limit = newplim;
    687 	}
    688 	if (ptmp->p_limit->pl_corename != defcorename)
    689 		FREE(ptmp->p_limit->pl_corename, M_SYSCTLDATA);
    690 	ptmp->p_limit->pl_corename = tmp;
    691 
    692 	return (error);
    693 }
    694 
    695 /*
    696  * sysctl helper routine for checking/setting a process's stop flags,
    697  * one for fork and one for exec.
    698  */
    699 static int
    700 sysctl_proc_stop(SYSCTLFN_ARGS)
    701 {
    702 	struct proc *p, *ptmp;
    703 	int i, f, error = 0;
    704 	struct sysctlnode node;
    705 
    706 	if (namelen != 0)
    707 		return (EINVAL);
    708 
    709 	p = l->l_proc;
    710 	error = sysctl_proc_findproc(p, &ptmp, (pid_t)name[-2]);
    711 	if (error)
    712 		return (error);
    713 
    714 	switch (rnode->sysctl_num) {
    715 	case PROC_PID_STOPFORK:
    716 		f = P_STOPFORK;
    717 		break;
    718 	case PROC_PID_STOPEXEC:
    719 		f = P_STOPEXEC;
    720 		break;
    721 #ifdef PROC_PID_STOPEXIT
    722 	case PROC_PID_STOPEXIT:
    723 		f = P_STOPEXIT;
    724 		break;
    725 #endif /* PROC_PID_STOPEXIT */
    726 	default:
    727 		return (EINVAL);
    728 	}
    729 
    730 	i = (ptmp->p_flag & f) ? 1 : 0;
    731 	node = *rnode;
    732 	node.sysctl_data = &i;
    733 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
    734 	if (error || newp == NULL)
    735 		return (error);
    736 
    737 	if (i)
    738 		ptmp->p_flag |= f;
    739 	else
    740 		ptmp->p_flag &= ~f;
    741 
    742 	return (0);
    743 }
    744 
    745 /*
    746  * sysctl helper routine for a process's rlimits as exposed by sysctl.
    747  */
    748 static int
    749 sysctl_proc_plimit(SYSCTLFN_ARGS)
    750 {
    751 	struct proc *ptmp, *p;
    752 	u_int limitno;
    753 	int which, error = 0;
    754         struct rlimit alim;
    755 	struct sysctlnode node;
    756 
    757 	if (namelen != 0)
    758 		return (EINVAL);
    759 
    760 	which = name[-1];
    761 	if (which != PROC_PID_LIMIT_TYPE_SOFT &&
    762 	    which != PROC_PID_LIMIT_TYPE_HARD)
    763 		return (EINVAL);
    764 
    765 	limitno = name[-2] - 1;
    766 	if (limitno >= RLIM_NLIMITS)
    767 		return (EINVAL);
    768 
    769 	if (name[-3] != PROC_PID_LIMIT)
    770 		return (EINVAL);
    771 
    772 	p = l->l_proc;
    773 	error = sysctl_proc_findproc(p, &ptmp, (pid_t)name[-4]);
    774 	if (error)
    775 		return (error);
    776 
    777 	node = *rnode;
    778 	memcpy(&alim, &ptmp->p_rlimit[limitno], sizeof(alim));
    779 	if (which == PROC_PID_LIMIT_TYPE_HARD)
    780 		node.sysctl_data = &alim.rlim_max;
    781 	else
    782 		node.sysctl_data = &alim.rlim_cur;
    783 
    784 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
    785 	if (error || newp == NULL)
    786 		return (error);
    787 
    788 	return (dosetrlimit(ptmp, p->p_cred, limitno, &alim));
    789 }
    790 
    791 /*
    792  * and finally, the actually glue that sticks it to the tree
    793  */
    794 SYSCTL_SETUP(sysctl_proc_setup, "sysctl proc subtree setup")
    795 {
    796 
    797 	sysctl_createv(SYSCTL_PERMANENT,
    798 		       CTLTYPE_NODE, "proc", NULL,
    799 		       NULL, 0, NULL, 0,
    800 		       CTL_PROC, CTL_EOL);
    801 	sysctl_createv(SYSCTL_PERMANENT|SYSCTL_ANYNUMBER,
    802 		       CTLTYPE_NODE, "curproc", NULL,
    803 		       NULL, 0, NULL, 0,
    804 		       CTL_PROC, PROC_CURPROC, CTL_EOL);
    805 
    806 	sysctl_createv(SYSCTL_PERMANENT|SYSCTL_READONLY2|SYSCTL_ANYWRITE,
    807 		       CTLTYPE_STRING, "corename", NULL,
    808 		       sysctl_proc_corename, 0, NULL, MAXPATHLEN,
    809 		       CTL_PROC, PROC_CURPROC, PROC_PID_CORENAME, CTL_EOL);
    810 	sysctl_createv(SYSCTL_PERMANENT,
    811 		       CTLTYPE_NODE, "rlimit", NULL,
    812 		       NULL, 0, NULL, 0,
    813 		       CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, CTL_EOL);
    814 
    815 #define create_proc_plimit(s, n) do {					\
    816 	sysctl_createv(SYSCTL_PERMANENT,				\
    817 		       CTLTYPE_NODE, s, NULL,				\
    818 		       NULL, 0, NULL, 0,				\
    819 		       CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, n,	\
    820 		       CTL_EOL);					\
    821 	sysctl_createv(SYSCTL_PERMANENT|SYSCTL_READWRITE|SYSCTL_ANYWRITE, \
    822 		       CTLTYPE_QUAD, "soft", NULL,			\
    823 		       sysctl_proc_plimit, 0, NULL, 0,			\
    824 		       CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, n,	\
    825 		       PROC_PID_LIMIT_TYPE_SOFT, CTL_EOL);		\
    826 	sysctl_createv(SYSCTL_PERMANENT|SYSCTL_READWRITE|SYSCTL_ANYWRITE, \
    827 		       CTLTYPE_QUAD, "hard", NULL,			\
    828 		       sysctl_proc_plimit, 0, NULL, 0,			\
    829 		       CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, n,	\
    830 		       PROC_PID_LIMIT_TYPE_HARD, CTL_EOL);		\
    831 	} while (0/*CONSTCOND*/)
    832 
    833 	create_proc_plimit("cputime",		PROC_PID_LIMIT_CPU);
    834 	create_proc_plimit("filesize",		PROC_PID_LIMIT_FSIZE);
    835 	create_proc_plimit("datasize",		PROC_PID_LIMIT_DATA);
    836 	create_proc_plimit("stacksize",		PROC_PID_LIMIT_STACK);
    837 	create_proc_plimit("coredumpsize",	PROC_PID_LIMIT_CORE);
    838 	create_proc_plimit("memoryuse",		PROC_PID_LIMIT_RSS);
    839 	create_proc_plimit("memorylocked",	PROC_PID_LIMIT_MEMLOCK);
    840 	create_proc_plimit("maxproc",		PROC_PID_LIMIT_NPROC);
    841 	create_proc_plimit("descriptors",	PROC_PID_LIMIT_NOFILE);
    842 
    843 #undef create_proc_plimit
    844 
    845 	sysctl_createv(SYSCTL_PERMANENT|SYSCTL_READWRITE|SYSCTL_ANYWRITE,
    846 		       CTLTYPE_INT, "stopfork", NULL,
    847 		       sysctl_proc_stop, 0, NULL, 0,
    848 		       CTL_PROC, PROC_CURPROC, PROC_PID_STOPFORK, CTL_EOL);
    849 	sysctl_createv(SYSCTL_PERMANENT|SYSCTL_READWRITE|SYSCTL_ANYWRITE,
    850 		       CTLTYPE_INT, "stopexec", NULL,
    851 		       sysctl_proc_stop, 0, NULL, 0,
    852 		       CTL_PROC, PROC_CURPROC, PROC_PID_STOPEXEC, CTL_EOL);
    853 #ifdef PROC_PID_STOPEXIT
    854 	sysctl_createv(SYSCTL_PERMANENT|SYSCTL_READWRITE|SYSCTL_ANYWRITE,
    855 		       CTLTYPE_INT, "stopexit", NULL,
    856 		       sysctl_proc_stop, 0, NULL, 0,
    857 		       CTL_PROC, PROC_CURPROC, PROC_PID_STOPEXIT, CTL_EOL);
    858 #endif /* PROC_PID_STOPEXIT */
    859 }
    860