xref: /dragonfly/sys/kern/kern_resource.c (revision 23265324)
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  * $FreeBSD: src/sys/kern/kern_resource.c,v 1.55.2.5 2001/11/03 01:41:08 ps Exp $
40  * $DragonFly: src/sys/kern/kern_resource.c,v 1.31 2007/02/03 17:05:58 corecode Exp $
41  */
42 
43 #include "opt_compat.h"
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/sysproto.h>
48 #include <sys/file.h>
49 #include <sys/kern_syscall.h>
50 #include <sys/kernel.h>
51 #include <sys/resourcevar.h>
52 #include <sys/malloc.h>
53 #include <sys/proc.h>
54 #include <sys/time.h>
55 #include <sys/lockf.h>
56 
57 #include <vm/vm.h>
58 #include <vm/vm_param.h>
59 #include <sys/lock.h>
60 #include <vm/pmap.h>
61 #include <vm/vm_map.h>
62 
63 #include <sys/thread2.h>
64 
65 static int donice (struct proc *chgp, int n);
66 
67 static MALLOC_DEFINE(M_UIDINFO, "uidinfo", "uidinfo structures");
68 #define	UIHASH(uid)	(&uihashtbl[(uid) & uihash])
69 static LIST_HEAD(uihashhead, uidinfo) *uihashtbl;
70 static u_long uihash;		/* size of hash table - 1 */
71 
72 static struct uidinfo	*uicreate (uid_t uid);
73 static struct uidinfo	*uilookup (uid_t uid);
74 
75 /*
76  * Resource controls and accounting.
77  */
78 
79 struct getpriority_info {
80 	int low;
81 	int who;
82 };
83 
84 static int getpriority_callback(struct proc *p, void *data);
85 
86 int
87 sys_getpriority(struct getpriority_args *uap)
88 {
89 	struct getpriority_info info;
90 	struct proc *curp = curproc;
91 	struct proc *p;
92 	int low = PRIO_MAX + 1;
93 
94 	switch (uap->which) {
95 	case PRIO_PROCESS:
96 		if (uap->who == 0)
97 			p = curp;
98 		else
99 			p = pfind(uap->who);
100 		if (p == 0)
101 			break;
102 		if (!PRISON_CHECK(curp->p_ucred, p->p_ucred))
103 			break;
104 		low = p->p_nice;
105 		break;
106 
107 	case PRIO_PGRP:
108 	{
109 		struct pgrp *pg;
110 
111 		if (uap->who == 0)
112 			pg = curp->p_pgrp;
113 		else if ((pg = pgfind(uap->who)) == NULL)
114 			break;
115 		LIST_FOREACH(p, &pg->pg_members, p_pglist) {
116 			if ((PRISON_CHECK(curp->p_ucred, p->p_ucred) && p->p_nice < low))
117 				low = p->p_nice;
118 		}
119 		break;
120 	}
121 	case PRIO_USER:
122 		if (uap->who == 0)
123 			uap->who = curp->p_ucred->cr_uid;
124 		info.low = low;
125 		info.who = uap->who;
126 		allproc_scan(getpriority_callback, &info);
127 		low = info.low;
128 		break;
129 
130 	default:
131 		return (EINVAL);
132 	}
133 	if (low == PRIO_MAX + 1)
134 		return (ESRCH);
135 	uap->sysmsg_result = low;
136 	return (0);
137 }
138 
139 /*
140  * Figure out the current lowest nice priority for processes owned
141  * by the specified user.
142  */
143 static
144 int
145 getpriority_callback(struct proc *p, void *data)
146 {
147 	struct getpriority_info *info = data;
148 
149 	if (PRISON_CHECK(curproc->p_ucred, p->p_ucred) &&
150 	    p->p_ucred->cr_uid == info->who &&
151 	    p->p_nice < info->low) {
152 		info->low = p->p_nice;
153 	}
154 	return(0);
155 }
156 
157 struct setpriority_info {
158 	int prio;
159 	int who;
160 	int error;
161 	int found;
162 };
163 
164 static int setpriority_callback(struct proc *p, void *data);
165 
166 int
167 sys_setpriority(struct setpriority_args *uap)
168 {
169 	struct setpriority_info info;
170 	struct proc *curp = curproc;
171 	struct proc *p;
172 	int found = 0, error = 0;
173 
174 	switch (uap->which) {
175 	case PRIO_PROCESS:
176 		if (uap->who == 0)
177 			p = curp;
178 		else
179 			p = pfind(uap->who);
180 		if (p == 0)
181 			break;
182 		if (!PRISON_CHECK(curp->p_ucred, p->p_ucred))
183 			break;
184 		error = donice(p, uap->prio);
185 		found++;
186 		break;
187 
188 	case PRIO_PGRP:
189 	{
190 		struct pgrp *pg;
191 
192 		if (uap->who == 0)
193 			pg = curp->p_pgrp;
194 		else if ((pg = pgfind(uap->who)) == NULL)
195 			break;
196 		LIST_FOREACH(p, &pg->pg_members, p_pglist) {
197 			if (PRISON_CHECK(curp->p_ucred, p->p_ucred)) {
198 				error = donice(p, uap->prio);
199 				found++;
200 			}
201 		}
202 		break;
203 	}
204 	case PRIO_USER:
205 		if (uap->who == 0)
206 			uap->who = curp->p_ucred->cr_uid;
207 		info.prio = uap->prio;
208 		info.who = uap->who;
209 		info.error = 0;
210 		info.found = 0;
211 		allproc_scan(setpriority_callback, &info);
212 		error = info.error;
213 		found = info.found;
214 		break;
215 
216 	default:
217 		return (EINVAL);
218 	}
219 	if (found == 0)
220 		return (ESRCH);
221 	return (error);
222 }
223 
224 static
225 int
226 setpriority_callback(struct proc *p, void *data)
227 {
228 	struct setpriority_info *info = data;
229 	int error;
230 
231 	if (p->p_ucred->cr_uid == info->who &&
232 	    PRISON_CHECK(curproc->p_ucred, p->p_ucred)) {
233 		error = donice(p, info->prio);
234 		if (error)
235 			info->error = error;
236 		++info->found;
237 	}
238 	return(0);
239 }
240 
241 static int
242 donice(struct proc *chgp, int n)
243 {
244 	struct proc *curp = curproc;
245 	struct ucred *cr = curp->p_ucred;
246 	struct lwp *lp;
247 
248 	if (cr->cr_uid && cr->cr_ruid &&
249 	    cr->cr_uid != chgp->p_ucred->cr_uid &&
250 	    cr->cr_ruid != chgp->p_ucred->cr_uid)
251 		return (EPERM);
252 	if (n > PRIO_MAX)
253 		n = PRIO_MAX;
254 	if (n < PRIO_MIN)
255 		n = PRIO_MIN;
256 	if (n < chgp->p_nice && suser_cred(cr, 0))
257 		return (EACCES);
258 	chgp->p_nice = n;
259 	FOREACH_LWP_IN_PROC(lp, chgp)
260 		chgp->p_usched->resetpriority(lp);
261 	return (0);
262 }
263 
264 /*
265  * Set realtime priority
266  */
267 /* ARGSUSED */
268 int
269 sys_rtprio(struct rtprio_args *uap)
270 {
271 	struct proc *curp = curproc;
272 	struct proc *p;
273 	struct lwp *lp;
274 	struct ucred *cr = curp->p_ucred;
275 	struct rtprio rtp;
276 	int error;
277 
278 	error = copyin(uap->rtp, &rtp, sizeof(struct rtprio));
279 	if (error)
280 		return (error);
281 
282 	if (uap->pid == 0)
283 		p = curp;
284 	else
285 		p = pfind(uap->pid);
286 
287 	if (p == 0)
288 		return (ESRCH);
289 
290 	/* XXX lwp */
291 	lp = FIRST_LWP_IN_PROC(p);
292 	switch (uap->function) {
293 	case RTP_LOOKUP:
294 		return (copyout(&lp->lwp_rtprio, uap->rtp, sizeof(struct rtprio)));
295 	case RTP_SET:
296 		if (cr->cr_uid && cr->cr_ruid &&
297 		    cr->cr_uid != p->p_ucred->cr_uid &&
298 		    cr->cr_ruid != p->p_ucred->cr_uid)
299 		        return (EPERM);
300 		/* disallow setting rtprio in most cases if not superuser */
301 		if (suser_cred(cr, 0)) {
302 			/* can't set someone else's */
303 			if (uap->pid)
304 				return (EPERM);
305 			/* can't set realtime priority */
306 /*
307  * Realtime priority has to be restricted for reasons which should be
308  * obvious. However, for idle priority, there is a potential for
309  * system deadlock if an idleprio process gains a lock on a resource
310  * that other processes need (and the idleprio process can't run
311  * due to a CPU-bound normal process). Fix me! XXX
312  */
313  			if (RTP_PRIO_IS_REALTIME(rtp.type))
314 				return (EPERM);
315 		}
316 		switch (rtp.type) {
317 #ifdef RTP_PRIO_FIFO
318 		case RTP_PRIO_FIFO:
319 #endif
320 		case RTP_PRIO_REALTIME:
321 		case RTP_PRIO_NORMAL:
322 		case RTP_PRIO_IDLE:
323 			if (rtp.prio > RTP_PRIO_MAX)
324 				return (EINVAL);
325 			lp->lwp_rtprio = rtp;
326 			return (0);
327 		default:
328 			return (EINVAL);
329 		}
330 
331 	default:
332 		return (EINVAL);
333 	}
334 }
335 
336 int
337 sys_setrlimit(struct __setrlimit_args *uap)
338 {
339 	struct rlimit alim;
340 	int error;
341 
342 	error = copyin(uap->rlp, &alim, sizeof(alim));
343 	if (error)
344 		return (error);
345 
346 	error = kern_setrlimit(uap->which, &alim);
347 
348 	return (error);
349 }
350 
351 int
352 sys_getrlimit(struct __getrlimit_args *uap)
353 {
354 	struct rlimit lim;
355 	int error;
356 
357 	error = kern_getrlimit(uap->which, &lim);
358 
359 	if (error == 0)
360 		error = copyout(&lim, uap->rlp, sizeof(*uap->rlp));
361 	return error;
362 }
363 
364 /*
365  * Transform the running time and tick information in lwp lp's thread into user,
366  * system, and interrupt time usage.
367  *
368  * Since we are limited to statclock tick granularity this is a statisical
369  * calculation which will be correct over the long haul, but should not be
370  * expected to measure fine grained deltas.
371  */
372 void
373 calcru(struct lwp *lp, struct timeval *up, struct timeval *sp)
374 {
375 	struct thread *td = lp->lwp_thread;
376 
377 	/*
378 	 * Calculate at the statclock level.  YYY if the thread is owned by
379 	 * another cpu we need to forward the request to the other cpu, or
380 	 * have a token to interlock the information.
381 	 */
382 	crit_enter();
383 	up->tv_sec = td->td_uticks / 1000000;
384 	up->tv_usec = td->td_uticks % 1000000;
385 	sp->tv_sec = td->td_sticks / 1000000;
386 	sp->tv_usec = td->td_sticks % 1000000;
387 	crit_exit();
388 }
389 
390 /*
391  * Aggregate resource statistics of all lwps of a process.
392  *
393  * proc.p_ru keeps track of all statistics directly related to a proc.  This
394  * consists of RSS usage and nswap information and aggregate numbers for all
395  * former lwps of this proc.
396  *
397  * proc.p_cru is the sum of all stats of reaped children.
398  *
399  * lwp.lwp_ru contains the stats directly related to one specific lwp, meaning
400  * packet, scheduler switch or page fault counts, etc.  This information gets
401  * added to lwp.lwp_proc.p_ru when the lwp exits.
402  */
403 void
404 calcru_proc(struct proc *p, struct rusage *ru)
405 {
406 	struct timeval upt, spt;
407 	long *rip1, *rip2;
408 	struct lwp *lp;
409 
410 	*ru = p->p_ru;
411 
412 	FOREACH_LWP_IN_PROC(lp, p) {
413 		calcru(lp, &upt, &spt);
414 		timevaladd(&ru->ru_utime, &upt);
415 		timevaladd(&ru->ru_stime, &spt);
416 		for (rip1 = &ru->ru_first, rip2 = &lp->lwp_ru.ru_first;
417 		     rip1 <= &ru->ru_last;
418 		     rip1++, rip2++)
419 			*rip1 += *rip2;
420 	}
421 }
422 
423 
424 /* ARGSUSED */
425 int
426 sys_getrusage(struct getrusage_args *uap)
427 {
428 	struct rusage ru;
429 	struct rusage *rup;
430 
431 	switch (uap->who) {
432 
433 	case RUSAGE_SELF:
434 		rup = &ru;
435 		calcru_proc(curproc, rup);
436 		break;
437 
438 	case RUSAGE_CHILDREN:
439 		rup = &curproc->p_cru;
440 		break;
441 
442 	default:
443 		return (EINVAL);
444 	}
445 	return (copyout((caddr_t)rup, (caddr_t)uap->rusage,
446 	    sizeof (struct rusage)));
447 }
448 
449 void
450 ruadd(struct rusage *ru, struct rusage *ru2)
451 {
452 	long *ip, *ip2;
453 	int i;
454 
455 	timevaladd(&ru->ru_utime, &ru2->ru_utime);
456 	timevaladd(&ru->ru_stime, &ru2->ru_stime);
457 	if (ru->ru_maxrss < ru2->ru_maxrss)
458 		ru->ru_maxrss = ru2->ru_maxrss;
459 	ip = &ru->ru_first; ip2 = &ru2->ru_first;
460 	for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--)
461 		*ip++ += *ip2++;
462 }
463 
464 /*
465  * Find the uidinfo structure for a uid.  This structure is used to
466  * track the total resource consumption (process count, socket buffer
467  * size, etc.) for the uid and impose limits.
468  */
469 void
470 uihashinit(void)
471 {
472 	uihashtbl = hashinit(maxproc / 16, M_UIDINFO, &uihash);
473 }
474 
475 static struct uidinfo *
476 uilookup(uid_t uid)
477 {
478 	struct	uihashhead *uipp;
479 	struct	uidinfo *uip;
480 
481 	uipp = UIHASH(uid);
482 	LIST_FOREACH(uip, uipp, ui_hash) {
483 		if (uip->ui_uid == uid)
484 			break;
485 	}
486 	return (uip);
487 }
488 
489 static struct uidinfo *
490 uicreate(uid_t uid)
491 {
492 	struct	uidinfo *uip, *norace;
493 
494 	/*
495 	 * Allocate space and check for a race
496 	 */
497 	MALLOC(uip, struct uidinfo *, sizeof(*uip), M_UIDINFO, M_WAITOK);
498 	norace = uilookup(uid);
499 	if (norace != NULL) {
500 		FREE(uip, M_UIDINFO);
501 		return (norace);
502 	}
503 
504 	/*
505 	 * Initialize structure and enter it into the hash table
506 	 */
507 	LIST_INSERT_HEAD(UIHASH(uid), uip, ui_hash);
508 	uip->ui_uid = uid;
509 	uip->ui_proccnt = 0;
510 	uip->ui_sbsize = 0;
511 	uip->ui_ref = 0;
512 	uip->ui_posixlocks = 0;
513 	varsymset_init(&uip->ui_varsymset, NULL);
514 	return (uip);
515 }
516 
517 struct uidinfo *
518 uifind(uid_t uid)
519 {
520 	struct	uidinfo *uip;
521 
522 	uip = uilookup(uid);
523 	if (uip == NULL)
524 		uip = uicreate(uid);
525 	uip->ui_ref++;
526 	return (uip);
527 }
528 
529 static __inline void
530 uifree(struct uidinfo *uip)
531 {
532 	if (uip->ui_sbsize != 0)
533 		/* XXX no %qd in kernel.  Truncate. */
534 		kprintf("freeing uidinfo: uid = %d, sbsize = %ld\n",
535 		    uip->ui_uid, (long)uip->ui_sbsize);
536 	if (uip->ui_proccnt != 0)
537 		kprintf("freeing uidinfo: uid = %d, proccnt = %ld\n",
538 		    uip->ui_uid, uip->ui_proccnt);
539 	LIST_REMOVE(uip, ui_hash);
540 	varsymset_clean(&uip->ui_varsymset);
541 	FREE(uip, M_UIDINFO);
542 }
543 
544 void
545 uihold(struct uidinfo *uip)
546 {
547 	++uip->ui_ref;
548 	KKASSERT(uip->ui_ref > 0);
549 }
550 
551 void
552 uidrop(struct uidinfo *uip)
553 {
554 	KKASSERT(uip->ui_ref > 0);
555 	if (--uip->ui_ref == 0)
556 		uifree(uip);
557 }
558 
559 void
560 uireplace(struct uidinfo **puip, struct uidinfo *nuip)
561 {
562 	uidrop(*puip);
563 	*puip = nuip;
564 }
565 
566 /*
567  * Change the count associated with number of processes
568  * a given user is using.  When 'max' is 0, don't enforce a limit
569  */
570 int
571 chgproccnt(struct uidinfo *uip, int diff, int max)
572 {
573 	/* don't allow them to exceed max, but allow subtraction */
574 	if (diff > 0 && uip->ui_proccnt + diff > max && max != 0)
575 		return (0);
576 	uip->ui_proccnt += diff;
577 	if (uip->ui_proccnt < 0)
578 		kprintf("negative proccnt for uid = %d\n", uip->ui_uid);
579 	return (1);
580 }
581 
582 /*
583  * Change the total socket buffer size a user has used.
584  */
585 int
586 chgsbsize(struct uidinfo *uip, u_long *hiwat, u_long to, rlim_t max)
587 {
588 	rlim_t new;
589 
590 	crit_enter();
591 	new = uip->ui_sbsize + to - *hiwat;
592 	/* don't allow them to exceed max, but allow subtraction */
593 	if (to > *hiwat && new > max) {
594 		crit_exit();
595 		return (0);
596 	}
597 	uip->ui_sbsize = new;
598 	*hiwat = to;
599 	if (uip->ui_sbsize < 0)
600 		kprintf("negative sbsize for uid = %d\n", uip->ui_uid);
601 	crit_exit();
602 	return (1);
603 }
604 
605