xref: /netbsd-src/sys/kern/kern_resource.c (revision d48f14661dda8638fee055ba15d35bdfb29b9fa8)
1 /*	$NetBSD: kern_resource.c,v 1.101 2006/05/14 21:15:11 elad 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 1.101 2006/05/14 21:15:11 elad 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/namei.h>
49 #include <sys/pool.h>
50 #include <sys/proc.h>
51 #include <sys/sysctl.h>
52 #include <sys/kauth.h>
53 
54 #include <sys/mount.h>
55 #include <sys/sa.h>
56 #include <sys/syscallargs.h>
57 
58 #include <uvm/uvm_extern.h>
59 
60 /*
61  * Maximum process data and stack limits.
62  * They are variables so they are patchable.
63  */
64 rlim_t maxdmap = MAXDSIZ;
65 rlim_t maxsmap = MAXSSIZ;
66 
67 struct uihashhead *uihashtbl;
68 u_long uihash;		/* size of hash table - 1 */
69 struct simplelock uihashtbl_slock = SIMPLELOCK_INITIALIZER;
70 
71 
72 /*
73  * Resource controls and accounting.
74  */
75 
76 int
77 sys_getpriority(struct lwp *l, void *v, register_t *retval)
78 {
79 	struct sys_getpriority_args /* {
80 		syscallarg(int) which;
81 		syscallarg(id_t) who;
82 	} */ *uap = v;
83 	struct proc *curp = l->l_proc, *p;
84 	int low = NZERO + PRIO_MAX + 1;
85 
86 	switch (SCARG(uap, which)) {
87 
88 	case PRIO_PROCESS:
89 		if (SCARG(uap, who) == 0)
90 			p = curp;
91 		else
92 			p = pfind(SCARG(uap, who));
93 		if (p == 0)
94 			break;
95 		low = p->p_nice;
96 		break;
97 
98 	case PRIO_PGRP: {
99 		struct pgrp *pg;
100 
101 		if (SCARG(uap, who) == 0)
102 			pg = curp->p_pgrp;
103 		else if ((pg = pgfind(SCARG(uap, who))) == NULL)
104 			break;
105 		LIST_FOREACH(p, &pg->pg_members, p_pglist) {
106 			if (p->p_nice < low)
107 				low = p->p_nice;
108 		}
109 		break;
110 	}
111 
112 	case PRIO_USER:
113 		if (SCARG(uap, who) == 0)
114 			SCARG(uap, who) = kauth_cred_geteuid(curp->p_cred);
115 		proclist_lock_read();
116 		PROCLIST_FOREACH(p, &allproc) {
117 			if (kauth_cred_geteuid(p->p_cred) == (uid_t) SCARG(uap, who) &&
118 			    p->p_nice < low)
119 				low = p->p_nice;
120 		}
121 		proclist_unlock_read();
122 		break;
123 
124 	default:
125 		return (EINVAL);
126 	}
127 	if (low == NZERO + PRIO_MAX + 1)
128 		return (ESRCH);
129 	*retval = low - NZERO;
130 	return (0);
131 }
132 
133 /* ARGSUSED */
134 int
135 sys_setpriority(struct lwp *l, void *v, register_t *retval)
136 {
137 	struct sys_setpriority_args /* {
138 		syscallarg(int) which;
139 		syscallarg(id_t) who;
140 		syscallarg(int) prio;
141 	} */ *uap = v;
142 	struct proc *curp = l->l_proc, *p;
143 	int found = 0, error = 0;
144 
145 	switch (SCARG(uap, which)) {
146 
147 	case PRIO_PROCESS:
148 		if (SCARG(uap, who) == 0)
149 			p = curp;
150 		else
151 			p = pfind(SCARG(uap, who));
152 		if (p == 0)
153 			break;
154 		error = donice(curp, p, SCARG(uap, prio));
155 		found++;
156 		break;
157 
158 	case PRIO_PGRP: {
159 		struct pgrp *pg;
160 
161 		if (SCARG(uap, who) == 0)
162 			pg = curp->p_pgrp;
163 		else if ((pg = pgfind(SCARG(uap, who))) == NULL)
164 			break;
165 		LIST_FOREACH(p, &pg->pg_members, p_pglist) {
166 			error = donice(curp, p, SCARG(uap, prio));
167 			found++;
168 		}
169 		break;
170 	}
171 
172 	case PRIO_USER:
173 		if (SCARG(uap, who) == 0)
174 			SCARG(uap, who) = kauth_cred_geteuid(curp->p_cred);
175 		proclist_lock_read();
176 		PROCLIST_FOREACH(p, &allproc) {
177 			if (kauth_cred_geteuid(p->p_cred) == (uid_t) SCARG(uap, who)) {
178 				error = donice(curp, p, SCARG(uap, prio));
179 				found++;
180 			}
181 		}
182 		proclist_unlock_read();
183 		break;
184 
185 	default:
186 		return (EINVAL);
187 	}
188 	if (found == 0)
189 		return (ESRCH);
190 	return (error);
191 }
192 
193 int
194 donice(struct proc *curp, struct proc *chgp, int n)
195 {
196 	kauth_cred_t cred = curp->p_cred;
197 	int s;
198 
199 	if (kauth_cred_geteuid(cred) && kauth_cred_getuid(cred) &&
200 	    kauth_cred_geteuid(cred) != kauth_cred_geteuid(chgp->p_cred) &&
201 	    kauth_cred_getuid(cred) != kauth_cred_geteuid(chgp->p_cred))
202 		return (EPERM);
203 	if (n > PRIO_MAX)
204 		n = PRIO_MAX;
205 	if (n < PRIO_MIN)
206 		n = PRIO_MIN;
207 	n += NZERO;
208 	if (n < chgp->p_nice && kauth_authorize_generic(cred, KAUTH_GENERIC_ISSUSER,
209 						  &curp->p_acflag))
210 		return (EACCES);
211 	chgp->p_nice = n;
212 	SCHED_LOCK(s);
213 	(void)resetprocpriority(chgp);
214 	SCHED_UNLOCK(s);
215 	return (0);
216 }
217 
218 /* ARGSUSED */
219 int
220 sys_setrlimit(struct lwp *l, void *v, register_t *retval)
221 {
222 	struct sys_setrlimit_args /* {
223 		syscallarg(int) which;
224 		syscallarg(const struct rlimit *) rlp;
225 	} */ *uap = v;
226 	struct proc *p = l->l_proc;
227 	int which = SCARG(uap, which);
228 	struct rlimit alim;
229 	int error;
230 
231 	error = copyin(SCARG(uap, rlp), &alim, sizeof(struct rlimit));
232 	if (error)
233 		return (error);
234 	return (dosetrlimit(p, p->p_cred, which, &alim));
235 }
236 
237 int
238 dosetrlimit(struct proc *p, kauth_cred_t cred, int which, struct rlimit *limp)
239 {
240 	struct rlimit *alimp;
241 	struct plimit *oldplim;
242 	int error;
243 
244 	if ((u_int)which >= RLIM_NLIMITS)
245 		return (EINVAL);
246 
247 	if (limp->rlim_cur < 0 || limp->rlim_max < 0)
248 		return (EINVAL);
249 
250 	alimp = &p->p_rlimit[which];
251 	/* if we don't change the value, no need to limcopy() */
252 	if (limp->rlim_cur == alimp->rlim_cur &&
253 	    limp->rlim_max == alimp->rlim_max)
254 		return 0;
255 
256 	if (limp->rlim_cur > limp->rlim_max) {
257 		/*
258 		 * This is programming error. According to SUSv2, we should
259 		 * return error in this case.
260 		 */
261 		return (EINVAL);
262 	}
263 	if (limp->rlim_max > alimp->rlim_max
264 	    && (error = kauth_authorize_generic(cred, KAUTH_GENERIC_ISSUSER,
265 					  &p->p_acflag)) != 0)
266 			return (error);
267 
268 	if (p->p_limit->p_refcnt > 1 &&
269 	    (p->p_limit->p_lflags & PL_SHAREMOD) == 0) {
270 		p->p_limit = limcopy(oldplim = p->p_limit);
271 		limfree(oldplim);
272 		alimp = &p->p_rlimit[which];
273 	}
274 
275 	switch (which) {
276 
277 	case RLIMIT_DATA:
278 		if (limp->rlim_cur > maxdmap)
279 			limp->rlim_cur = maxdmap;
280 		if (limp->rlim_max > maxdmap)
281 			limp->rlim_max = maxdmap;
282 		break;
283 
284 	case RLIMIT_STACK:
285 		if (limp->rlim_cur > maxsmap)
286 			limp->rlim_cur = maxsmap;
287 		if (limp->rlim_max > maxsmap)
288 			limp->rlim_max = maxsmap;
289 
290 		/*
291 		 * Return EINVAL if the new stack size limit is lower than
292 		 * current usage. Otherwise, the process would get SIGSEGV the
293 		 * moment it would try to access anything on it's current stack.
294 		 * This conforms to SUSv2.
295 		 */
296 		if (limp->rlim_cur < p->p_vmspace->vm_ssize * PAGE_SIZE
297 		    || limp->rlim_max < p->p_vmspace->vm_ssize * PAGE_SIZE)
298 			return (EINVAL);
299 
300 		/*
301 		 * Stack is allocated to the max at exec time with
302 		 * only "rlim_cur" bytes accessible (In other words,
303 		 * allocates stack dividing two contiguous regions at
304 		 * "rlim_cur" bytes boundary).
305 		 *
306 		 * Since allocation is done in terms of page, roundup
307 		 * "rlim_cur" (otherwise, contiguous regions
308 		 * overlap).  If stack limit is going up make more
309 		 * accessible, if going down make inaccessible.
310 		 */
311 		limp->rlim_cur = round_page(limp->rlim_cur);
312 		if (limp->rlim_cur != alimp->rlim_cur) {
313 			vaddr_t addr;
314 			vsize_t size;
315 			vm_prot_t prot;
316 
317 			if (limp->rlim_cur > alimp->rlim_cur) {
318 				prot = VM_PROT_READ | VM_PROT_WRITE;
319 				size = limp->rlim_cur - alimp->rlim_cur;
320 				addr = (vaddr_t)p->p_vmspace->vm_minsaddr -
321 				    limp->rlim_cur;
322 			} else {
323 				prot = VM_PROT_NONE;
324 				size = alimp->rlim_cur - limp->rlim_cur;
325 				addr = (vaddr_t)p->p_vmspace->vm_minsaddr -
326 				     alimp->rlim_cur;
327 			}
328 			(void) uvm_map_protect(&p->p_vmspace->vm_map,
329 					      addr, addr+size, prot, FALSE);
330 		}
331 		break;
332 
333 	case RLIMIT_NOFILE:
334 		if (limp->rlim_cur > maxfiles)
335 			limp->rlim_cur = maxfiles;
336 		if (limp->rlim_max > maxfiles)
337 			limp->rlim_max = maxfiles;
338 		break;
339 
340 	case RLIMIT_NPROC:
341 		if (limp->rlim_cur > maxproc)
342 			limp->rlim_cur = maxproc;
343 		if (limp->rlim_max > maxproc)
344 			limp->rlim_max = maxproc;
345 		break;
346 	}
347 	*alimp = *limp;
348 	return (0);
349 }
350 
351 /* ARGSUSED */
352 int
353 sys_getrlimit(struct lwp *l, void *v, register_t *retval)
354 {
355 	struct sys_getrlimit_args /* {
356 		syscallarg(int) which;
357 		syscallarg(struct rlimit *) rlp;
358 	} */ *uap = v;
359 	struct proc *p = l->l_proc;
360 	int which = SCARG(uap, which);
361 
362 	if ((u_int)which >= RLIM_NLIMITS)
363 		return (EINVAL);
364 	return (copyout(&p->p_rlimit[which], SCARG(uap, rlp),
365 	    sizeof(struct rlimit)));
366 }
367 
368 /*
369  * Transform the running time and tick information in proc p into user,
370  * system, and interrupt time usage.
371  */
372 void
373 calcru(struct proc *p, struct timeval *up, struct timeval *sp,
374     struct timeval *ip)
375 {
376 	u_quad_t u, st, ut, it, tot;
377 	unsigned long sec;
378 	long usec;
379 	int s;
380 	struct timeval tv;
381 	struct lwp *l;
382 
383 	s = splstatclock();
384 	st = p->p_sticks;
385 	ut = p->p_uticks;
386 	it = p->p_iticks;
387 	splx(s);
388 
389 	sec = p->p_rtime.tv_sec;
390 	usec = p->p_rtime.tv_usec;
391 	LIST_FOREACH(l, &p->p_lwps, l_sibling) {
392 		if (l->l_stat == LSONPROC) {
393 			struct schedstate_percpu *spc;
394 
395 			KDASSERT(l->l_cpu != NULL);
396 			spc = &l->l_cpu->ci_schedstate;
397 
398 			/*
399 			 * Adjust for the current time slice.  This is
400 			 * actually fairly important since the error
401 			 * here is on the order of a time quantum,
402 			 * which is much greater than the sampling
403 			 * error.
404 			 */
405 			microtime(&tv);
406 			sec += tv.tv_sec - spc->spc_runtime.tv_sec;
407 			usec += tv.tv_usec - spc->spc_runtime.tv_usec;
408 		}
409 	}
410 
411 	tot = st + ut + it;
412 	u = sec * 1000000ull + usec;
413 
414 	if (tot == 0) {
415 		/* No ticks, so can't use to share time out, split 50-50 */
416 		st = ut = u / 2;
417 	} else {
418 		st = (u * st) / tot;
419 		ut = (u * ut) / tot;
420 	}
421 	sp->tv_sec = st / 1000000;
422 	sp->tv_usec = st % 1000000;
423 	up->tv_sec = ut / 1000000;
424 	up->tv_usec = ut % 1000000;
425 	if (ip != NULL) {
426 		if (it != 0)
427 			it = (u * it) / tot;
428 		ip->tv_sec = it / 1000000;
429 		ip->tv_usec = it % 1000000;
430 	}
431 }
432 
433 /* ARGSUSED */
434 int
435 sys_getrusage(struct lwp *l, void *v, register_t *retval)
436 {
437 	struct sys_getrusage_args /* {
438 		syscallarg(int) who;
439 		syscallarg(struct rusage *) rusage;
440 	} */ *uap = v;
441 	struct rusage *rup;
442 	struct proc *p = l->l_proc;
443 
444 	switch (SCARG(uap, who)) {
445 
446 	case RUSAGE_SELF:
447 		rup = &p->p_stats->p_ru;
448 		calcru(p, &rup->ru_utime, &rup->ru_stime, NULL);
449 		break;
450 
451 	case RUSAGE_CHILDREN:
452 		rup = &p->p_stats->p_cru;
453 		break;
454 
455 	default:
456 		return (EINVAL);
457 	}
458 	return (copyout(rup, SCARG(uap, rusage), sizeof(struct rusage)));
459 }
460 
461 void
462 ruadd(struct rusage *ru, struct rusage *ru2)
463 {
464 	long *ip, *ip2;
465 	int i;
466 
467 	timeradd(&ru->ru_utime, &ru2->ru_utime, &ru->ru_utime);
468 	timeradd(&ru->ru_stime, &ru2->ru_stime, &ru->ru_stime);
469 	if (ru->ru_maxrss < ru2->ru_maxrss)
470 		ru->ru_maxrss = ru2->ru_maxrss;
471 	ip = &ru->ru_first; ip2 = &ru2->ru_first;
472 	for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--)
473 		*ip++ += *ip2++;
474 }
475 
476 /*
477  * Make a copy of the plimit structure.
478  * We share these structures copy-on-write after fork,
479  * and copy when a limit is changed.
480  */
481 struct plimit *
482 limcopy(struct plimit *lim)
483 {
484 	struct plimit *newlim;
485 	size_t l = 0;
486 
487 	simple_lock(&lim->p_slock);
488 	if (lim->pl_corename != defcorename)
489 		l = strlen(lim->pl_corename) + 1;
490 	simple_unlock(&lim->p_slock);
491 
492 	newlim = pool_get(&plimit_pool, PR_WAITOK);
493 	simple_lock_init(&newlim->p_slock);
494 	newlim->p_lflags = 0;
495 	newlim->p_refcnt = 1;
496 	newlim->pl_corename = (l != 0)
497 		? malloc(l, M_TEMP, M_WAITOK)
498 		: defcorename;
499 
500 	simple_lock(&lim->p_slock);
501 	memcpy(newlim->pl_rlimit, lim->pl_rlimit,
502 	    sizeof(struct rlimit) * RLIM_NLIMITS);
503 
504 	if (l != 0)
505 		strlcpy(newlim->pl_corename, lim->pl_corename, l);
506 	simple_unlock(&lim->p_slock);
507 
508 	return (newlim);
509 }
510 
511 void
512 limfree(struct plimit *lim)
513 {
514 	int n;
515 
516 	simple_lock(&lim->p_slock);
517 	n = --lim->p_refcnt;
518 	simple_unlock(&lim->p_slock);
519 	if (n > 0)
520 		return;
521 #ifdef DIAGNOSTIC
522 	if (n < 0)
523 		panic("limfree");
524 #endif
525 	if (lim->pl_corename != defcorename)
526 		free(lim->pl_corename, M_TEMP);
527 	pool_put(&plimit_pool, lim);
528 }
529 
530 struct pstats *
531 pstatscopy(struct pstats *ps)
532 {
533 
534 	struct pstats *newps;
535 
536 	newps = pool_get(&pstats_pool, PR_WAITOK);
537 
538 	memset(&newps->pstat_startzero, 0,
539 	(unsigned) ((caddr_t)&newps->pstat_endzero -
540 		    (caddr_t)&newps->pstat_startzero));
541 	memcpy(&newps->pstat_startcopy, &ps->pstat_startcopy,
542 	((caddr_t)&newps->pstat_endcopy -
543 	 (caddr_t)&newps->pstat_startcopy));
544 
545 	return (newps);
546 
547 }
548 
549 void
550 pstatsfree(struct pstats *ps)
551 {
552 
553 	pool_put(&pstats_pool, ps);
554 }
555 
556 /*
557  * sysctl interface in five parts
558  */
559 
560 /*
561  * a routine for sysctl proc subtree helpers that need to pick a valid
562  * process by pid.
563  */
564 static int
565 sysctl_proc_findproc(struct proc *p, struct proc **p2, pid_t pid)
566 {
567 	struct proc *ptmp;
568 	int error = 0;
569 
570 	if (pid == PROC_CURPROC)
571 		ptmp = p;
572 	else if ((ptmp = pfind(pid)) == NULL)
573 		error = ESRCH;
574 	else {
575 		/*
576 		 * suid proc of ours or proc not ours
577 		 */
578 		if (kauth_cred_getuid(p->p_cred) != kauth_cred_getuid(ptmp->p_cred) ||
579 		    kauth_cred_getuid(p->p_cred) != kauth_cred_getsvuid(ptmp->p_cred))
580 			error = kauth_authorize_generic(p->p_cred,
581 				    KAUTH_GENERIC_ISSUSER, &p->p_acflag);
582 
583 		/*
584 		 * sgid proc has sgid back to us temporarily
585 		 */
586 		else if (kauth_cred_getgid(ptmp->p_cred) != kauth_cred_getsvgid(ptmp->p_cred))
587 			error = kauth_authorize_generic(p->p_cred,
588 			    KAUTH_GENERIC_ISSUSER, &p->p_acflag);
589 
590 		/*
591 		 * our rgid must be in target's group list (ie,
592 		 * sub-processes started by a sgid process)
593 		 */
594 		else {
595 			int ismember = 0;
596 
597 			if (kauth_cred_ismember_gid(p->p_cred,
598 			    kauth_cred_getgid(ptmp->p_cred), &ismember) != 0 ||
599 			    !ismember) {
600 				error = kauth_authorize_generic(p->p_cred,
601 				    KAUTH_GENERIC_ISSUSER, &p->p_acflag);
602 			}
603 		}
604 	}
605 
606 	*p2 = ptmp;
607 	return (error);
608 }
609 
610 /*
611  * sysctl helper routine for setting a process's specific corefile
612  * name.  picks the process based on the given pid and checks the
613  * correctness of the new value.
614  */
615 static int
616 sysctl_proc_corename(SYSCTLFN_ARGS)
617 {
618 	struct proc *ptmp, *p;
619 	struct plimit *lim;
620 	int error = 0, len;
621 	char *cname;
622 	char *tmp;
623 	struct sysctlnode node;
624 
625 	/*
626 	 * is this all correct?
627 	 */
628 	if (namelen != 0)
629 		return (EINVAL);
630 	if (name[-1] != PROC_PID_CORENAME)
631 		return (EINVAL);
632 
633 	/*
634 	 * whom are we tweaking?
635 	 */
636 	p = l->l_proc;
637 	error = sysctl_proc_findproc(p, &ptmp, (pid_t)name[-2]);
638 	if (error)
639 		return (error);
640 
641 	cname = PNBUF_GET();
642 	/*
643 	 * let them modify a temporary copy of the core name
644 	 */
645 	node = *rnode;
646 	strlcpy(cname, ptmp->p_limit->pl_corename, MAXPATHLEN);
647 	node.sysctl_data = cname;
648 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
649 
650 	/*
651 	 * if that failed, or they have nothing new to say, or we've
652 	 * heard it before...
653 	 */
654 	if (error || newp == NULL ||
655 	    strcmp(cname, ptmp->p_limit->pl_corename) == 0) {
656 		goto done;
657 	}
658 
659 	/*
660 	 * no error yet and cname now has the new core name in it.
661 	 * let's see if it looks acceptable.  it must be either "core"
662 	 * or end in ".core" or "/core".
663 	 */
664 	len = strlen(cname);
665 	if (len < 4) {
666 		error = EINVAL;
667 	} else if (strcmp(cname + len - 4, "core") != 0) {
668 		error = EINVAL;
669 	} else if (len > 4 && cname[len - 5] != '/' && cname[len - 5] != '.') {
670 		error = EINVAL;
671 	}
672 	if (error != 0) {
673 		goto done;
674 	}
675 
676 	/*
677 	 * hmm...looks good.  now...where do we put it?
678 	 */
679 	tmp = malloc(len + 1, M_TEMP, M_WAITOK|M_CANFAIL);
680 	if (tmp == NULL) {
681 		error = ENOMEM;
682 		goto done;
683 	}
684 	strlcpy(tmp, cname, len + 1);
685 
686 	lim = ptmp->p_limit;
687 	if (lim->p_refcnt > 1 && (lim->p_lflags & PL_SHAREMOD) == 0) {
688 		ptmp->p_limit = limcopy(lim);
689 		limfree(lim);
690 		lim = ptmp->p_limit;
691 	}
692 	if (lim->pl_corename != defcorename)
693 		free(lim->pl_corename, M_TEMP);
694 	lim->pl_corename = tmp;
695 done:
696 	PNBUF_PUT(cname);
697 	return error;
698 }
699 
700 /*
701  * sysctl helper routine for checking/setting a process's stop flags,
702  * one for fork and one for exec.
703  */
704 static int
705 sysctl_proc_stop(SYSCTLFN_ARGS)
706 {
707 	struct proc *p, *ptmp;
708 	int i, f, error = 0;
709 	struct sysctlnode node;
710 
711 	if (namelen != 0)
712 		return (EINVAL);
713 
714 	p = l->l_proc;
715 	error = sysctl_proc_findproc(p, &ptmp, (pid_t)name[-2]);
716 	if (error)
717 		return (error);
718 
719 	switch (rnode->sysctl_num) {
720 	case PROC_PID_STOPFORK:
721 		f = P_STOPFORK;
722 		break;
723 	case PROC_PID_STOPEXEC:
724 		f = P_STOPEXEC;
725 		break;
726 	case PROC_PID_STOPEXIT:
727 		f = P_STOPEXIT;
728 		break;
729 	default:
730 		return (EINVAL);
731 	}
732 
733 	i = (ptmp->p_flag & f) ? 1 : 0;
734 	node = *rnode;
735 	node.sysctl_data = &i;
736 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
737 	if (error || newp == NULL)
738 		return (error);
739 
740 	if (i)
741 		ptmp->p_flag |= f;
742 	else
743 		ptmp->p_flag &= ~f;
744 
745 	return (0);
746 }
747 
748 /*
749  * sysctl helper routine for a process's rlimits as exposed by sysctl.
750  */
751 static int
752 sysctl_proc_plimit(SYSCTLFN_ARGS)
753 {
754 	struct proc *ptmp, *p;
755 	u_int limitno;
756 	int which, error = 0;
757         struct rlimit alim;
758 	struct sysctlnode node;
759 
760 	if (namelen != 0)
761 		return (EINVAL);
762 
763 	which = name[-1];
764 	if (which != PROC_PID_LIMIT_TYPE_SOFT &&
765 	    which != PROC_PID_LIMIT_TYPE_HARD)
766 		return (EINVAL);
767 
768 	limitno = name[-2] - 1;
769 	if (limitno >= RLIM_NLIMITS)
770 		return (EINVAL);
771 
772 	if (name[-3] != PROC_PID_LIMIT)
773 		return (EINVAL);
774 
775 	p = l->l_proc;
776 	error = sysctl_proc_findproc(p, &ptmp, (pid_t)name[-4]);
777 	if (error)
778 		return (error);
779 
780 	node = *rnode;
781 	memcpy(&alim, &ptmp->p_rlimit[limitno], sizeof(alim));
782 	if (which == PROC_PID_LIMIT_TYPE_HARD)
783 		node.sysctl_data = &alim.rlim_max;
784 	else
785 		node.sysctl_data = &alim.rlim_cur;
786 
787 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
788 	if (error || newp == NULL)
789 		return (error);
790 
791 	return (dosetrlimit(ptmp, p->p_cred, limitno, &alim));
792 }
793 
794 /*
795  * and finally, the actually glue that sticks it to the tree
796  */
797 SYSCTL_SETUP(sysctl_proc_setup, "sysctl proc subtree setup")
798 {
799 
800 	sysctl_createv(clog, 0, NULL, NULL,
801 		       CTLFLAG_PERMANENT,
802 		       CTLTYPE_NODE, "proc", NULL,
803 		       NULL, 0, NULL, 0,
804 		       CTL_PROC, CTL_EOL);
805 	sysctl_createv(clog, 0, NULL, NULL,
806 		       CTLFLAG_PERMANENT|CTLFLAG_ANYNUMBER,
807 		       CTLTYPE_NODE, "curproc",
808 		       SYSCTL_DESCR("Per-process settings"),
809 		       NULL, 0, NULL, 0,
810 		       CTL_PROC, PROC_CURPROC, CTL_EOL);
811 
812 	sysctl_createv(clog, 0, NULL, NULL,
813 		       CTLFLAG_PERMANENT|CTLFLAG_READONLY2|CTLFLAG_ANYWRITE,
814 		       CTLTYPE_STRING, "corename",
815 		       SYSCTL_DESCR("Core file name"),
816 		       sysctl_proc_corename, 0, NULL, MAXPATHLEN,
817 		       CTL_PROC, PROC_CURPROC, PROC_PID_CORENAME, CTL_EOL);
818 	sysctl_createv(clog, 0, NULL, NULL,
819 		       CTLFLAG_PERMANENT,
820 		       CTLTYPE_NODE, "rlimit",
821 		       SYSCTL_DESCR("Process limits"),
822 		       NULL, 0, NULL, 0,
823 		       CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, CTL_EOL);
824 
825 #define create_proc_plimit(s, n) do {					\
826 	sysctl_createv(clog, 0, NULL, NULL,				\
827 		       CTLFLAG_PERMANENT,				\
828 		       CTLTYPE_NODE, s,					\
829 		       SYSCTL_DESCR("Process " s " limits"),		\
830 		       NULL, 0, NULL, 0,				\
831 		       CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, n,	\
832 		       CTL_EOL);					\
833 	sysctl_createv(clog, 0, NULL, NULL,				\
834 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE, \
835 		       CTLTYPE_QUAD, "soft",				\
836 		       SYSCTL_DESCR("Process soft " s " limit"),	\
837 		       sysctl_proc_plimit, 0, NULL, 0,			\
838 		       CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, n,	\
839 		       PROC_PID_LIMIT_TYPE_SOFT, CTL_EOL);		\
840 	sysctl_createv(clog, 0, NULL, NULL,				\
841 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE, \
842 		       CTLTYPE_QUAD, "hard",				\
843 		       SYSCTL_DESCR("Process hard " s " limit"),	\
844 		       sysctl_proc_plimit, 0, NULL, 0,			\
845 		       CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, n,	\
846 		       PROC_PID_LIMIT_TYPE_HARD, CTL_EOL);		\
847 	} while (0/*CONSTCOND*/)
848 
849 	create_proc_plimit("cputime",		PROC_PID_LIMIT_CPU);
850 	create_proc_plimit("filesize",		PROC_PID_LIMIT_FSIZE);
851 	create_proc_plimit("datasize",		PROC_PID_LIMIT_DATA);
852 	create_proc_plimit("stacksize",		PROC_PID_LIMIT_STACK);
853 	create_proc_plimit("coredumpsize",	PROC_PID_LIMIT_CORE);
854 	create_proc_plimit("memoryuse",		PROC_PID_LIMIT_RSS);
855 	create_proc_plimit("memorylocked",	PROC_PID_LIMIT_MEMLOCK);
856 	create_proc_plimit("maxproc",		PROC_PID_LIMIT_NPROC);
857 	create_proc_plimit("descriptors",	PROC_PID_LIMIT_NOFILE);
858 	create_proc_plimit("sbsize",		PROC_PID_LIMIT_SBSIZE);
859 
860 #undef create_proc_plimit
861 
862 	sysctl_createv(clog, 0, NULL, NULL,
863 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE,
864 		       CTLTYPE_INT, "stopfork",
865 		       SYSCTL_DESCR("Stop process at fork(2)"),
866 		       sysctl_proc_stop, 0, NULL, 0,
867 		       CTL_PROC, PROC_CURPROC, PROC_PID_STOPFORK, CTL_EOL);
868 	sysctl_createv(clog, 0, NULL, NULL,
869 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE,
870 		       CTLTYPE_INT, "stopexec",
871 		       SYSCTL_DESCR("Stop process at execve(2)"),
872 		       sysctl_proc_stop, 0, NULL, 0,
873 		       CTL_PROC, PROC_CURPROC, PROC_PID_STOPEXEC, CTL_EOL);
874 	sysctl_createv(clog, 0, NULL, NULL,
875 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE,
876 		       CTLTYPE_INT, "stopexit",
877 		       SYSCTL_DESCR("Stop process before completing exit"),
878 		       sysctl_proc_stop, 0, NULL, 0,
879 		       CTL_PROC, PROC_CURPROC, PROC_PID_STOPEXIT, CTL_EOL);
880 }
881 
882 struct uidinfo *
883 uid_find(uid_t uid)
884 {
885 	struct uidinfo *uip;
886 	struct uidinfo *newuip = NULL;
887 	struct uihashhead *uipp;
888 
889 	uipp = UIHASH(uid);
890 
891 again:
892 	simple_lock(&uihashtbl_slock);
893 	LIST_FOREACH(uip, uipp, ui_hash)
894 		if (uip->ui_uid == uid) {
895 			simple_unlock(&uihashtbl_slock);
896 			if (newuip)
897 				free(newuip, M_PROC);
898 			return uip;
899 		}
900 
901 	if (newuip == NULL) {
902 		simple_unlock(&uihashtbl_slock);
903 		newuip = malloc(sizeof(*uip), M_PROC, M_WAITOK | M_ZERO);
904 		goto again;
905 	}
906 	uip = newuip;
907 
908 	LIST_INSERT_HEAD(uipp, uip, ui_hash);
909 	uip->ui_uid = uid;
910 	simple_lock_init(&uip->ui_slock);
911 	simple_unlock(&uihashtbl_slock);
912 
913 	return uip;
914 }
915 
916 /*
917  * Change the count associated with number of processes
918  * a given user is using.
919  */
920 int
921 chgproccnt(uid_t uid, int diff)
922 {
923 	struct uidinfo *uip;
924 	int s;
925 
926 	if (diff == 0)
927 		return 0;
928 
929 	uip = uid_find(uid);
930 	UILOCK(uip, s);
931 	uip->ui_proccnt += diff;
932 	KASSERT(uip->ui_proccnt >= 0);
933 	UIUNLOCK(uip, s);
934 	return uip->ui_proccnt;
935 }
936 
937 int
938 chgsbsize(struct uidinfo *uip, u_long *hiwat, u_long to, rlim_t xmax)
939 {
940 	rlim_t nsb;
941 	int s;
942 
943 	UILOCK(uip, s);
944 	nsb = uip->ui_sbsize + to - *hiwat;
945 	if (to > *hiwat && nsb > xmax) {
946 		UIUNLOCK(uip, s);
947 		splx(s);
948 		return 0;
949 	}
950 	*hiwat = to;
951 	uip->ui_sbsize = nsb;
952 	KASSERT(uip->ui_sbsize >= 0);
953 	UIUNLOCK(uip, s);
954 	return 1;
955 }
956