xref: /freebsd/sys/kern/kern_resource.c (revision a316b26e50bbed7cf655fbba726ab87d8ab7599d)
1 /*-
2  * Copyright (c) 1982, 1986, 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  * (c) UNIX System Laboratories, Inc.
5  * All or some portions of this file are derived from material licensed
6  * to the University of California by American Telephone and Telegraph
7  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8  * the permission of UNIX System Laboratories, 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_resource.c	8.5 (Berkeley) 1/21/94
39  * $Id: kern_resource.c,v 1.9 1994/12/02 23:00:40 ats Exp $
40  */
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/proc.h>
49 
50 #include <vm/vm.h>
51 
52 int	donice __P((struct proc *, struct proc *, int));
53 int	dosetrlimit __P((struct proc *, u_int, struct rlimit *));
54 
55 /*
56  * Resource controls and accounting.
57  */
58 
59 struct getpriority_args {
60 	int	which;
61 	int	who;
62 };
63 int
64 getpriority(curp, uap, retval)
65 	struct proc *curp;
66 	register struct getpriority_args *uap;
67 	int *retval;
68 {
69 	register struct proc *p;
70 	register int low = PRIO_MAX + 1;
71 
72 	switch (uap->which) {
73 
74 	case PRIO_PROCESS:
75 		if (uap->who == 0)
76 			p = curp;
77 		else
78 			p = pfind(uap->who);
79 		if (p == 0)
80 			break;
81 		low = p->p_nice;
82 		break;
83 
84 	case PRIO_PGRP: {
85 		register struct pgrp *pg;
86 
87 		if (uap->who == 0)
88 			pg = curp->p_pgrp;
89 		else if ((pg = pgfind(uap->who)) == NULL)
90 			break;
91 		for (p = pg->pg_mem; p != NULL; p = p->p_pgrpnxt) {
92 			if (p->p_nice < low)
93 				low = p->p_nice;
94 		}
95 		break;
96 	}
97 
98 	case PRIO_USER:
99 		if (uap->who == 0)
100 			uap->who = curp->p_ucred->cr_uid;
101 		for (p = (struct proc *)allproc; p != NULL; p = p->p_next) {
102 			if (p->p_ucred->cr_uid == uap->who &&
103 			    p->p_nice < low)
104 				low = p->p_nice;
105 		}
106 		break;
107 
108 	default:
109 		return (EINVAL);
110 	}
111 	if (low == PRIO_MAX + 1)
112 		return (ESRCH);
113 	*retval = low;
114 	return (0);
115 }
116 
117 struct setpriority_args {
118 	int	which;
119 	int	who;
120 	int	prio;
121 };
122 /* ARGSUSED */
123 int
124 setpriority(curp, uap, retval)
125 	struct proc *curp;
126 	register struct setpriority_args *uap;
127 	int *retval;
128 {
129 	register struct proc *p;
130 	int found = 0, error = 0;
131 
132 	switch (uap->which) {
133 
134 	case PRIO_PROCESS:
135 		if (uap->who == 0)
136 			p = curp;
137 		else
138 			p = pfind(uap->who);
139 		if (p == 0)
140 			break;
141 		error = donice(curp, p, uap->prio);
142 		found++;
143 		break;
144 
145 	case PRIO_PGRP: {
146 		register struct pgrp *pg;
147 
148 		if (uap->who == 0)
149 			pg = curp->p_pgrp;
150 		else if ((pg = pgfind(uap->who)) == NULL)
151 			break;
152 		for (p = pg->pg_mem; p != NULL; p = p->p_pgrpnxt) {
153 			error = donice(curp, p, uap->prio);
154 			found++;
155 		}
156 		break;
157 	}
158 
159 	case PRIO_USER:
160 		if (uap->who == 0)
161 			uap->who = curp->p_ucred->cr_uid;
162 		for (p = (struct proc *)allproc; p != NULL; p = p->p_next)
163 			if (p->p_ucred->cr_uid == uap->who) {
164 				error = donice(curp, p, uap->prio);
165 				found++;
166 			}
167 		break;
168 
169 	default:
170 		return (EINVAL);
171 	}
172 	if (found == 0)
173 		return (ESRCH);
174 	return (error);
175 }
176 
177 int
178 donice(curp, chgp, n)
179 	register struct proc *curp, *chgp;
180 	register int n;
181 {
182 	register struct pcred *pcred = curp->p_cred;
183 
184 	if (pcred->pc_ucred->cr_uid && pcred->p_ruid &&
185 	    pcred->pc_ucred->cr_uid != chgp->p_ucred->cr_uid &&
186 	    pcred->p_ruid != chgp->p_ucred->cr_uid)
187 		return (EPERM);
188 	if (n > PRIO_MAX)
189 		n = PRIO_MAX;
190 	if (n < PRIO_MIN)
191 		n = PRIO_MIN;
192 	if (n < chgp->p_nice && suser(pcred->pc_ucred, &curp->p_acflag))
193 		return (EACCES);
194 	chgp->p_nice = n;
195 	(void)resetpriority(chgp);
196 	return (0);
197 }
198 
199 /* rtprio system call */
200 struct rtprio_args {
201 	int		function;
202 	pid_t		pid;
203 	struct rtprio	*rtprio;
204 };
205 
206 /*
207  * Set realtime priority
208  */
209 
210 /* ARGSUSED */
211 int
212 rtprio(curp, uap, retval)
213 	struct proc *curp;
214 	register struct rtprio_args *uap;
215 	int *retval;
216 {
217 	register struct proc *p;
218 	register struct pcred *pcred = curp->p_cred;
219 	struct rtprio rtp;
220 	int error;
221 
222 	error = copyin(uap->rtprio, &rtp, sizeof(struct rtprio));
223 	if (error)
224 		return (error);
225 
226 	if (uap->pid == 0)
227 		p = curp;
228 	else
229 		p = pfind(uap->pid);
230 
231 	if (p == 0)
232 		return (ESRCH);
233 
234 	switch (uap->function) {
235 	case RTP_LOOKUP:
236 		return (copyout(&p->p_rtprio, uap->rtprio, sizeof(struct rtprio)));
237 	case RTP_SET:
238 		if (pcred->pc_ucred->cr_uid && pcred->p_ruid &&
239 		    pcred->pc_ucred->cr_uid != p->p_ucred->cr_uid &&
240 		    pcred->p_ruid != p->p_ucred->cr_uid)
241 		        return (EPERM);
242 		/* disallow setting rtprio in most cases if not superuser */
243 		if (suser(pcred->pc_ucred, &curp->p_acflag)) {
244 			/* can't set someone else's */
245 			if (uap->pid)
246 				return (EPERM);
247 			/* can't set realtime priority */
248 			if (rtp.type == RTP_PRIO_REALTIME)
249 				return (EPERM);
250 		}
251 		switch (rtp.type) {
252 		case RTP_PRIO_REALTIME:
253 		case RTP_PRIO_NORMAL:
254 		case RTP_PRIO_IDLE:
255 			if (rtp.prio > RTP_PRIO_MAX)
256 				return (EINVAL);
257 			p->p_rtprio = rtp;
258 			return (0);
259 		default:
260 			return (EINVAL);
261 		}
262 
263 	default:
264 		return (EINVAL);
265 	}
266 }
267 
268 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
269 struct setrlimit_args {
270 	u_int	which;
271 	struct	orlimit *lim;
272 };
273 /* ARGSUSED */
274 int
275 osetrlimit(p, uap, retval)
276 	struct proc *p;
277 	register struct setrlimit_args *uap;
278 	int *retval;
279 {
280 	struct orlimit olim;
281 	struct rlimit lim;
282 	int error;
283 
284 	if ((error =
285 	    copyin((caddr_t)uap->lim, (caddr_t)&olim, sizeof(struct orlimit))))
286 		return (error);
287 	lim.rlim_cur = olim.rlim_cur;
288 	lim.rlim_max = olim.rlim_max;
289 	return (dosetrlimit(p, uap->which, &lim));
290 }
291 
292 struct getrlimit_args {
293 	u_int	which;
294 	struct	orlimit *rlp;
295 };
296 /* ARGSUSED */
297 int
298 ogetrlimit(p, uap, retval)
299 	struct proc *p;
300 	register struct getrlimit_args *uap;
301 	int *retval;
302 {
303 	struct orlimit olim;
304 
305 	if (uap->which >= RLIM_NLIMITS)
306 		return (EINVAL);
307 	olim.rlim_cur = p->p_rlimit[uap->which].rlim_cur;
308 	if (olim.rlim_cur == -1)
309 		olim.rlim_cur = 0x7fffffff;
310 	olim.rlim_max = p->p_rlimit[uap->which].rlim_max;
311 	if (olim.rlim_max == -1)
312 		olim.rlim_max = 0x7fffffff;
313 	return (copyout((caddr_t)&olim, (caddr_t)uap->rlp, sizeof(olim)));
314 }
315 #endif /* COMPAT_43 || COMPAT_SUNOS */
316 
317 struct __setrlimit_args {
318 	u_int	which;
319 	struct	rlimit *lim;
320 };
321 /* ARGSUSED */
322 int
323 setrlimit(p, uap, retval)
324 	struct proc *p;
325 	register struct __setrlimit_args *uap;
326 	int *retval;
327 {
328 	struct rlimit alim;
329 	int error;
330 
331 	if ((error =
332 	    copyin((caddr_t)uap->lim, (caddr_t)&alim, sizeof (struct rlimit))))
333 		return (error);
334 	return (dosetrlimit(p, uap->which, &alim));
335 }
336 
337 int
338 dosetrlimit(p, which, limp)
339 	struct proc *p;
340 	u_int which;
341 	struct rlimit *limp;
342 {
343 	register struct rlimit *alimp;
344 	int error;
345 
346 	if (which >= RLIM_NLIMITS)
347 		return (EINVAL);
348 	alimp = &p->p_rlimit[which];
349 
350 	/*
351 	 * Preserve historical bugs by treating negative limits as unsigned.
352 	 */
353 	if (limp->rlim_cur < 0)
354 		limp->rlim_cur = RLIM_INFINITY;
355 	if (limp->rlim_max < 0)
356 		limp->rlim_max = RLIM_INFINITY;
357 
358 	if (limp->rlim_cur > alimp->rlim_max ||
359 	    limp->rlim_max > alimp->rlim_max)
360 		if ((error = suser(p->p_ucred, &p->p_acflag)))
361 			return (error);
362 	if (limp->rlim_cur > limp->rlim_max)
363 		limp->rlim_cur = limp->rlim_max;
364 	if (p->p_limit->p_refcnt > 1 &&
365 	    (p->p_limit->p_lflags & PL_SHAREMOD) == 0) {
366 		p->p_limit->p_refcnt--;
367 		p->p_limit = limcopy(p->p_limit);
368 		alimp = &p->p_rlimit[which];
369 	}
370 
371 	switch (which) {
372 
373 	case RLIMIT_DATA:
374 		if (limp->rlim_cur > MAXDSIZ)
375 			limp->rlim_cur = MAXDSIZ;
376 		if (limp->rlim_max > MAXDSIZ)
377 			limp->rlim_max = MAXDSIZ;
378 		break;
379 
380 	case RLIMIT_STACK:
381 		if (limp->rlim_cur > MAXSSIZ)
382 			limp->rlim_cur = MAXSSIZ;
383 		if (limp->rlim_max > MAXSSIZ)
384 			limp->rlim_max = MAXSSIZ;
385 		/*
386 		 * Stack is allocated to the max at exec time with only
387 		 * "rlim_cur" bytes accessible.  If stack limit is going
388 		 * up make more accessible, if going down make inaccessible.
389 		 */
390 		if (limp->rlim_cur != alimp->rlim_cur) {
391 			vm_offset_t addr;
392 			vm_size_t size;
393 			vm_prot_t prot;
394 
395 			if (limp->rlim_cur > alimp->rlim_cur) {
396 				prot = VM_PROT_ALL;
397 				size = limp->rlim_cur - alimp->rlim_cur;
398 				addr = USRSTACK - limp->rlim_cur;
399 			} else {
400 				prot = VM_PROT_NONE;
401 				size = alimp->rlim_cur - limp->rlim_cur;
402 				addr = USRSTACK - alimp->rlim_cur;
403 			}
404 			addr = trunc_page(addr);
405 			size = round_page(size);
406 			(void) vm_map_protect(&p->p_vmspace->vm_map,
407 					      addr, addr+size, prot, FALSE);
408 		}
409 		break;
410 
411 	case RLIMIT_NOFILE:
412 		if (limp->rlim_cur > maxfiles)
413 			limp->rlim_cur = maxfiles;
414 		if (limp->rlim_max > maxfiles)
415 			limp->rlim_max = maxfiles;
416 		break;
417 
418 	case RLIMIT_NPROC:
419 		if (limp->rlim_cur > maxproc)
420 			limp->rlim_cur = maxproc;
421 		if (limp->rlim_max > maxproc)
422 			limp->rlim_max = maxproc;
423 		break;
424 	}
425 	*alimp = *limp;
426 	return (0);
427 }
428 
429 struct __getrlimit_args {
430 	u_int	which;
431 	struct	rlimit *rlp;
432 };
433 /* ARGSUSED */
434 int
435 getrlimit(p, uap, retval)
436 	struct proc *p;
437 	register struct __getrlimit_args *uap;
438 	int *retval;
439 {
440 
441 	if (uap->which >= RLIM_NLIMITS)
442 		return (EINVAL);
443 	return (copyout((caddr_t)&p->p_rlimit[uap->which], (caddr_t)uap->rlp,
444 	    sizeof (struct rlimit)));
445 }
446 
447 /*
448  * Transform the running time and tick information in proc p into user,
449  * system, and interrupt time usage.
450  */
451 void
452 calcru(p, up, sp, ip)
453 	register struct proc *p;
454 	register struct timeval *up;
455 	register struct timeval *sp;
456 	register struct timeval *ip;
457 {
458 	register u_quad_t u, st, ut, it, tot;
459 	register u_long sec, usec;
460 	register int s;
461 	struct timeval tv;
462 
463 	s = splstatclock();
464 	st = p->p_sticks;
465 	ut = p->p_uticks;
466 	it = p->p_iticks;
467 	splx(s);
468 
469 	tot = st + ut + it;
470 	if (tot == 0) {
471 		up->tv_sec = up->tv_usec = 0;
472 		sp->tv_sec = sp->tv_usec = 0;
473 		if (ip != NULL)
474 			ip->tv_sec = ip->tv_usec = 0;
475 		return;
476 	}
477 
478 	sec = p->p_rtime.tv_sec;
479 	usec = p->p_rtime.tv_usec;
480 	if (p == curproc) {
481 		/*
482 		 * Adjust for the current time slice.  This is actually fairly
483 		 * important since the error here is on the order of a time
484 		 * quantum, which is much greater than the sampling error.
485 		 */
486 		microtime(&tv);
487 		sec += tv.tv_sec - runtime.tv_sec;
488 		usec += tv.tv_usec - runtime.tv_usec;
489 	}
490 	u = sec * 1000000 + usec;
491 	st = (u * st) / tot;
492 	sp->tv_sec = st / 1000000;
493 	sp->tv_usec = st % 1000000;
494 	ut = (u * ut) / tot;
495 	up->tv_sec = ut / 1000000;
496 	up->tv_usec = ut % 1000000;
497 	if (ip != NULL) {
498 		it = (u * it) / tot;
499 		ip->tv_sec = it / 1000000;
500 		ip->tv_usec = it % 1000000;
501 	}
502 }
503 
504 struct getrusage_args {
505 	int	who;
506 	struct	rusage *rusage;
507 };
508 /* ARGSUSED */
509 int
510 getrusage(p, uap, retval)
511 	register struct proc *p;
512 	register struct getrusage_args *uap;
513 	int *retval;
514 {
515 	register struct rusage *rup;
516 
517 	switch (uap->who) {
518 
519 	case RUSAGE_SELF:
520 		rup = &p->p_stats->p_ru;
521 		calcru(p, &rup->ru_utime, &rup->ru_stime, NULL);
522 		break;
523 
524 	case RUSAGE_CHILDREN:
525 		rup = &p->p_stats->p_cru;
526 		break;
527 
528 	default:
529 		return (EINVAL);
530 	}
531 	return (copyout((caddr_t)rup, (caddr_t)uap->rusage,
532 	    sizeof (struct rusage)));
533 }
534 
535 void
536 ruadd(ru, ru2)
537 	register struct rusage *ru, *ru2;
538 {
539 	register long *ip, *ip2;
540 	register int i;
541 
542 	timevaladd(&ru->ru_utime, &ru2->ru_utime);
543 	timevaladd(&ru->ru_stime, &ru2->ru_stime);
544 	if (ru->ru_maxrss < ru2->ru_maxrss)
545 		ru->ru_maxrss = ru2->ru_maxrss;
546 	ip = &ru->ru_first; ip2 = &ru2->ru_first;
547 	for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--)
548 		*ip++ += *ip2++;
549 }
550 
551 /*
552  * Make a copy of the plimit structure.
553  * We share these structures copy-on-write after fork,
554  * and copy when a limit is changed.
555  */
556 struct plimit *
557 limcopy(lim)
558 	struct plimit *lim;
559 {
560 	register struct plimit *copy;
561 
562 	MALLOC(copy, struct plimit *, sizeof(struct plimit),
563 	    M_SUBPROC, M_WAITOK);
564 	bcopy(lim->pl_rlimit, copy->pl_rlimit,
565 	    sizeof(struct rlimit) * RLIM_NLIMITS);
566 	copy->p_lflags = 0;
567 	copy->p_refcnt = 1;
568 	return (copy);
569 }
570