xref: /netbsd-src/sys/kern/kern_resource.c (revision 313c6c94c424eed90c7b7e494aa83308a0a5d0ce)
1 /*	$NetBSD: kern_resource.c,v 1.152 2009/05/26 06:57:38 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 1.152 2009/05/26 06:57:38 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/kmem.h>
49 #include <sys/namei.h>
50 #include <sys/pool.h>
51 #include <sys/proc.h>
52 #include <sys/sysctl.h>
53 #include <sys/timevar.h>
54 #include <sys/kauth.h>
55 #include <sys/atomic.h>
56 #include <sys/mount.h>
57 #include <sys/syscallargs.h>
58 #include <sys/atomic.h>
59 
60 #include <uvm/uvm_extern.h>
61 
62 /*
63  * Maximum process data and stack limits.
64  * They are variables so they are patchable.
65  */
66 rlim_t maxdmap = MAXDSIZ;
67 rlim_t maxsmap = MAXSSIZ;
68 
69 static pool_cache_t	plimit_cache;
70 static pool_cache_t	pstats_cache;
71 
72 void
73 resource_init(void)
74 {
75 
76 	plimit_cache = pool_cache_init(sizeof(struct plimit), 0, 0, 0,
77 	    "plimitpl", NULL, IPL_NONE, NULL, NULL, NULL);
78 	pstats_cache = pool_cache_init(sizeof(struct pstats), 0, 0, 0,
79 	    "pstatspl", NULL, IPL_NONE, NULL, NULL, NULL);
80 }
81 
82 /*
83  * Resource controls and accounting.
84  */
85 
86 int
87 sys_getpriority(struct lwp *l, const struct sys_getpriority_args *uap,
88     register_t *retval)
89 {
90 	/* {
91 		syscallarg(int) which;
92 		syscallarg(id_t) who;
93 	} */
94 	struct proc *curp = l->l_proc, *p;
95 	int low = NZERO + PRIO_MAX + 1;
96 	int who = SCARG(uap, who);
97 
98 	mutex_enter(proc_lock);
99 	switch (SCARG(uap, which)) {
100 	case PRIO_PROCESS:
101 		if (who == 0)
102 			p = curp;
103 		else
104 			p = p_find(who, PFIND_LOCKED);
105 		if (p != NULL)
106 			low = p->p_nice;
107 		break;
108 
109 	case PRIO_PGRP: {
110 		struct pgrp *pg;
111 
112 		if (who == 0)
113 			pg = curp->p_pgrp;
114 		else if ((pg = pg_find(who, PFIND_LOCKED)) == NULL)
115 			break;
116 		LIST_FOREACH(p, &pg->pg_members, p_pglist) {
117 			if (p->p_nice < low)
118 				low = p->p_nice;
119 		}
120 		break;
121 	}
122 
123 	case PRIO_USER:
124 		if (who == 0)
125 			who = (int)kauth_cred_geteuid(l->l_cred);
126 		PROCLIST_FOREACH(p, &allproc) {
127 			if ((p->p_flag & PK_MARKER) != 0)
128 				continue;
129 			mutex_enter(p->p_lock);
130 			if (kauth_cred_geteuid(p->p_cred) ==
131 			    (uid_t)who && p->p_nice < low)
132 				low = p->p_nice;
133 			mutex_exit(p->p_lock);
134 		}
135 		break;
136 
137 	default:
138 		mutex_exit(proc_lock);
139 		return (EINVAL);
140 	}
141 	mutex_exit(proc_lock);
142 
143 	if (low == NZERO + PRIO_MAX + 1)
144 		return (ESRCH);
145 	*retval = low - NZERO;
146 	return (0);
147 }
148 
149 /* ARGSUSED */
150 int
151 sys_setpriority(struct lwp *l, const struct sys_setpriority_args *uap,
152     register_t *retval)
153 {
154 	/* {
155 		syscallarg(int) which;
156 		syscallarg(id_t) who;
157 		syscallarg(int) prio;
158 	} */
159 	struct proc *curp = l->l_proc, *p;
160 	int found = 0, error = 0;
161 	int who = SCARG(uap, who);
162 
163 	mutex_enter(proc_lock);
164 	switch (SCARG(uap, which)) {
165 	case PRIO_PROCESS:
166 		if (who == 0)
167 			p = curp;
168 		else
169 			p = p_find(who, PFIND_LOCKED);
170 		if (p != 0) {
171 			mutex_enter(p->p_lock);
172 			error = donice(l, p, SCARG(uap, prio));
173 			mutex_exit(p->p_lock);
174 			found++;
175 		}
176 		break;
177 
178 	case PRIO_PGRP: {
179 		struct pgrp *pg;
180 
181 		if (who == 0)
182 			pg = curp->p_pgrp;
183 		else if ((pg = pg_find(who, PFIND_LOCKED)) == NULL)
184 			break;
185 		LIST_FOREACH(p, &pg->pg_members, p_pglist) {
186 			mutex_enter(p->p_lock);
187 			error = donice(l, p, SCARG(uap, prio));
188 			mutex_exit(p->p_lock);
189 			found++;
190 		}
191 		break;
192 	}
193 
194 	case PRIO_USER:
195 		if (who == 0)
196 			who = (int)kauth_cred_geteuid(l->l_cred);
197 		PROCLIST_FOREACH(p, &allproc) {
198 			if ((p->p_flag & PK_MARKER) != 0)
199 				continue;
200 			mutex_enter(p->p_lock);
201 			if (kauth_cred_geteuid(p->p_cred) ==
202 			    (uid_t)SCARG(uap, who)) {
203 				error = donice(l, p, SCARG(uap, prio));
204 				found++;
205 			}
206 			mutex_exit(p->p_lock);
207 		}
208 		break;
209 
210 	default:
211 		mutex_exit(proc_lock);
212 		return EINVAL;
213 	}
214 	mutex_exit(proc_lock);
215 	if (found == 0)
216 		return (ESRCH);
217 	return (error);
218 }
219 
220 /*
221  * Renice a process.
222  *
223  * Call with the target process' credentials locked.
224  */
225 int
226 donice(struct lwp *l, struct proc *chgp, int n)
227 {
228 	kauth_cred_t cred = l->l_cred;
229 
230 	KASSERT(mutex_owned(chgp->p_lock));
231 
232 	if (kauth_cred_geteuid(cred) && kauth_cred_getuid(cred) &&
233 	    kauth_cred_geteuid(cred) != kauth_cred_geteuid(chgp->p_cred) &&
234 	    kauth_cred_getuid(cred) != kauth_cred_geteuid(chgp->p_cred))
235 		return (EPERM);
236 
237 	if (n > PRIO_MAX)
238 		n = PRIO_MAX;
239 	if (n < PRIO_MIN)
240 		n = PRIO_MIN;
241 	n += NZERO;
242 	if (kauth_authorize_process(cred, KAUTH_PROCESS_NICE, chgp,
243 	    KAUTH_ARG(n), NULL, NULL))
244 		return (EACCES);
245 	sched_nice(chgp, n);
246 	return (0);
247 }
248 
249 /* ARGSUSED */
250 int
251 sys_setrlimit(struct lwp *l, const struct sys_setrlimit_args *uap,
252     register_t *retval)
253 {
254 	/* {
255 		syscallarg(int) which;
256 		syscallarg(const struct rlimit *) rlp;
257 	} */
258 	int which = SCARG(uap, which);
259 	struct rlimit alim;
260 	int error;
261 
262 	error = copyin(SCARG(uap, rlp), &alim, sizeof(struct rlimit));
263 	if (error)
264 		return (error);
265 	return (dosetrlimit(l, l->l_proc, which, &alim));
266 }
267 
268 int
269 dosetrlimit(struct lwp *l, struct proc *p, int which, struct rlimit *limp)
270 {
271 	struct rlimit *alimp;
272 	int error;
273 
274 	if ((u_int)which >= RLIM_NLIMITS)
275 		return (EINVAL);
276 
277 	if (limp->rlim_cur > limp->rlim_max) {
278 		/*
279 		 * This is programming error. According to SUSv2, we should
280 		 * return error in this case.
281 		 */
282 		return (EINVAL);
283 	}
284 
285 	alimp = &p->p_rlimit[which];
286 	/* if we don't change the value, no need to limcopy() */
287 	if (limp->rlim_cur == alimp->rlim_cur &&
288 	    limp->rlim_max == alimp->rlim_max)
289 		return 0;
290 
291 	error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_RLIMIT,
292 	    p, KAUTH_ARG(KAUTH_REQ_PROCESS_RLIMIT_SET), limp, KAUTH_ARG(which));
293 	if (error)
294 		return (error);
295 
296 	lim_privatise(p, false);
297 	/* p->p_limit is now unchangeable */
298 	alimp = &p->p_rlimit[which];
299 
300 	switch (which) {
301 
302 	case RLIMIT_DATA:
303 		if (limp->rlim_cur > maxdmap)
304 			limp->rlim_cur = maxdmap;
305 		if (limp->rlim_max > maxdmap)
306 			limp->rlim_max = maxdmap;
307 		break;
308 
309 	case RLIMIT_STACK:
310 		if (limp->rlim_cur > maxsmap)
311 			limp->rlim_cur = maxsmap;
312 		if (limp->rlim_max > maxsmap)
313 			limp->rlim_max = maxsmap;
314 
315 		/*
316 		 * Return EINVAL if the new stack size limit is lower than
317 		 * current usage. Otherwise, the process would get SIGSEGV the
318 		 * moment it would try to access anything on it's current stack.
319 		 * This conforms to SUSv2.
320 		 */
321 		if (limp->rlim_cur < p->p_vmspace->vm_ssize * PAGE_SIZE
322 		    || limp->rlim_max < p->p_vmspace->vm_ssize * PAGE_SIZE) {
323 			return (EINVAL);
324 		}
325 
326 		/*
327 		 * Stack is allocated to the max at exec time with
328 		 * only "rlim_cur" bytes accessible (In other words,
329 		 * allocates stack dividing two contiguous regions at
330 		 * "rlim_cur" bytes boundary).
331 		 *
332 		 * Since allocation is done in terms of page, roundup
333 		 * "rlim_cur" (otherwise, contiguous regions
334 		 * overlap).  If stack limit is going up make more
335 		 * accessible, if going down make inaccessible.
336 		 */
337 		limp->rlim_cur = round_page(limp->rlim_cur);
338 		if (limp->rlim_cur != alimp->rlim_cur) {
339 			vaddr_t addr;
340 			vsize_t size;
341 			vm_prot_t prot;
342 
343 			if (limp->rlim_cur > alimp->rlim_cur) {
344 				prot = VM_PROT_READ | VM_PROT_WRITE;
345 				size = limp->rlim_cur - alimp->rlim_cur;
346 				addr = (vaddr_t)p->p_vmspace->vm_minsaddr -
347 				    limp->rlim_cur;
348 			} else {
349 				prot = VM_PROT_NONE;
350 				size = alimp->rlim_cur - limp->rlim_cur;
351 				addr = (vaddr_t)p->p_vmspace->vm_minsaddr -
352 				     alimp->rlim_cur;
353 			}
354 			(void) uvm_map_protect(&p->p_vmspace->vm_map,
355 			    addr, addr+size, prot, false);
356 		}
357 		break;
358 
359 	case RLIMIT_NOFILE:
360 		if (limp->rlim_cur > maxfiles)
361 			limp->rlim_cur = maxfiles;
362 		if (limp->rlim_max > maxfiles)
363 			limp->rlim_max = maxfiles;
364 		break;
365 
366 	case RLIMIT_NPROC:
367 		if (limp->rlim_cur > maxproc)
368 			limp->rlim_cur = maxproc;
369 		if (limp->rlim_max > maxproc)
370 			limp->rlim_max = maxproc;
371 		break;
372 	}
373 
374 	mutex_enter(&p->p_limit->pl_lock);
375 	*alimp = *limp;
376 	mutex_exit(&p->p_limit->pl_lock);
377 	return (0);
378 }
379 
380 /* ARGSUSED */
381 int
382 sys_getrlimit(struct lwp *l, const struct sys_getrlimit_args *uap,
383     register_t *retval)
384 {
385 	/* {
386 		syscallarg(int) which;
387 		syscallarg(struct rlimit *) rlp;
388 	} */
389 	struct proc *p = l->l_proc;
390 	int which = SCARG(uap, which);
391 	struct rlimit rl;
392 
393 	if ((u_int)which >= RLIM_NLIMITS)
394 		return (EINVAL);
395 
396 	mutex_enter(p->p_lock);
397 	memcpy(&rl, &p->p_rlimit[which], sizeof(rl));
398 	mutex_exit(p->p_lock);
399 
400 	return copyout(&rl, SCARG(uap, rlp), sizeof(rl));
401 }
402 
403 /*
404  * Transform the running time and tick information in proc p into user,
405  * system, and interrupt time usage.
406  *
407  * Should be called with p->p_lock held unless called from exit1().
408  */
409 void
410 calcru(struct proc *p, struct timeval *up, struct timeval *sp,
411     struct timeval *ip, struct timeval *rp)
412 {
413 	uint64_t u, st, ut, it, tot;
414 	struct lwp *l;
415 	struct bintime tm;
416 	struct timeval tv;
417 
418 	mutex_spin_enter(&p->p_stmutex);
419 	st = p->p_sticks;
420 	ut = p->p_uticks;
421 	it = p->p_iticks;
422 	mutex_spin_exit(&p->p_stmutex);
423 
424 	tm = p->p_rtime;
425 
426 	LIST_FOREACH(l, &p->p_lwps, l_sibling) {
427 		lwp_lock(l);
428 		bintime_add(&tm, &l->l_rtime);
429 		if ((l->l_pflag & LP_RUNNING) != 0) {
430 			struct bintime diff;
431 			/*
432 			 * Adjust for the current time slice.  This is
433 			 * actually fairly important since the error
434 			 * here is on the order of a time quantum,
435 			 * which is much greater than the sampling
436 			 * error.
437 			 */
438 			binuptime(&diff);
439 			bintime_sub(&diff, &l->l_stime);
440 			bintime_add(&tm, &diff);
441 		}
442 		lwp_unlock(l);
443 	}
444 
445 	tot = st + ut + it;
446 	bintime2timeval(&tm, &tv);
447 	u = (uint64_t)tv.tv_sec * 1000000ul + tv.tv_usec;
448 
449 	if (tot == 0) {
450 		/* No ticks, so can't use to share time out, split 50-50 */
451 		st = ut = u / 2;
452 	} else {
453 		st = (u * st) / tot;
454 		ut = (u * ut) / tot;
455 	}
456 	if (sp != NULL) {
457 		sp->tv_sec = st / 1000000;
458 		sp->tv_usec = st % 1000000;
459 	}
460 	if (up != NULL) {
461 		up->tv_sec = ut / 1000000;
462 		up->tv_usec = ut % 1000000;
463 	}
464 	if (ip != NULL) {
465 		if (it != 0)
466 			it = (u * it) / tot;
467 		ip->tv_sec = it / 1000000;
468 		ip->tv_usec = it % 1000000;
469 	}
470 	if (rp != NULL) {
471 		*rp = tv;
472 	}
473 }
474 
475 /* ARGSUSED */
476 int
477 sys___getrusage50(struct lwp *l, const struct sys___getrusage50_args *uap,
478     register_t *retval)
479 {
480 	/* {
481 		syscallarg(int) who;
482 		syscallarg(struct rusage *) rusage;
483 	} */
484 	struct rusage ru;
485 	struct proc *p = l->l_proc;
486 
487 	switch (SCARG(uap, who)) {
488 	case RUSAGE_SELF:
489 		mutex_enter(p->p_lock);
490 		memcpy(&ru, &p->p_stats->p_ru, sizeof(ru));
491 		calcru(p, &ru.ru_utime, &ru.ru_stime, NULL, NULL);
492 		rulwps(p, &ru);
493 		mutex_exit(p->p_lock);
494 		break;
495 
496 	case RUSAGE_CHILDREN:
497 		mutex_enter(p->p_lock);
498 		memcpy(&ru, &p->p_stats->p_cru, sizeof(ru));
499 		mutex_exit(p->p_lock);
500 		break;
501 
502 	default:
503 		return EINVAL;
504 	}
505 
506 	return copyout(&ru, SCARG(uap, rusage), sizeof(ru));
507 }
508 
509 void
510 ruadd(struct rusage *ru, struct rusage *ru2)
511 {
512 	long *ip, *ip2;
513 	int i;
514 
515 	timeradd(&ru->ru_utime, &ru2->ru_utime, &ru->ru_utime);
516 	timeradd(&ru->ru_stime, &ru2->ru_stime, &ru->ru_stime);
517 	if (ru->ru_maxrss < ru2->ru_maxrss)
518 		ru->ru_maxrss = ru2->ru_maxrss;
519 	ip = &ru->ru_first; ip2 = &ru2->ru_first;
520 	for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--)
521 		*ip++ += *ip2++;
522 }
523 
524 void
525 rulwps(proc_t *p, struct rusage *ru)
526 {
527 	lwp_t *l;
528 
529 	KASSERT(mutex_owned(p->p_lock));
530 
531 	LIST_FOREACH(l, &p->p_lwps, l_sibling) {
532 		ruadd(ru, &l->l_ru);
533 		ru->ru_nvcsw += (l->l_ncsw - l->l_nivcsw);
534 		ru->ru_nivcsw += l->l_nivcsw;
535 	}
536 }
537 
538 /*
539  * Make a copy of the plimit structure.
540  * We share these structures copy-on-write after fork,
541  * and copy when a limit is changed.
542  *
543  * Unfortunately (due to PL_SHAREMOD) it is possibly for the structure
544  * we are copying to change beneath our feet!
545  */
546 struct plimit *
547 lim_copy(struct plimit *lim)
548 {
549 	struct plimit *newlim;
550 	char *corename;
551 	size_t alen, len;
552 
553 	newlim = pool_cache_get(plimit_cache, PR_WAITOK);
554 	mutex_init(&newlim->pl_lock, MUTEX_DEFAULT, IPL_NONE);
555 	newlim->pl_flags = 0;
556 	newlim->pl_refcnt = 1;
557 	newlim->pl_sv_limit = NULL;
558 
559 	mutex_enter(&lim->pl_lock);
560 	memcpy(newlim->pl_rlimit, lim->pl_rlimit,
561 	    sizeof(struct rlimit) * RLIM_NLIMITS);
562 
563 	alen = 0;
564 	corename = NULL;
565 	for (;;) {
566 		if (lim->pl_corename == defcorename) {
567 			newlim->pl_corename = defcorename;
568 			break;
569 		}
570 		len = strlen(lim->pl_corename) + 1;
571 		if (len <= alen) {
572 			newlim->pl_corename = corename;
573 			memcpy(corename, lim->pl_corename, len);
574 			corename = NULL;
575 			break;
576 		}
577 		mutex_exit(&lim->pl_lock);
578 		if (corename != NULL)
579 			free(corename, M_TEMP);
580 		alen = len;
581 		corename = malloc(alen, M_TEMP, M_WAITOK);
582 		mutex_enter(&lim->pl_lock);
583 	}
584 	mutex_exit(&lim->pl_lock);
585 	if (corename != NULL)
586 		free(corename, M_TEMP);
587 	return newlim;
588 }
589 
590 void
591 lim_addref(struct plimit *lim)
592 {
593 	atomic_inc_uint(&lim->pl_refcnt);
594 }
595 
596 /*
597  * Give a process it's own private plimit structure.
598  * This will only be shared (in fork) if modifications are to be shared.
599  */
600 void
601 lim_privatise(struct proc *p, bool set_shared)
602 {
603 	struct plimit *lim, *newlim;
604 
605 	lim = p->p_limit;
606 	if (lim->pl_flags & PL_WRITEABLE) {
607 		if (set_shared)
608 			lim->pl_flags |= PL_SHAREMOD;
609 		return;
610 	}
611 
612 	if (set_shared && lim->pl_flags & PL_SHAREMOD)
613 		return;
614 
615 	newlim = lim_copy(lim);
616 
617 	mutex_enter(p->p_lock);
618 	if (p->p_limit->pl_flags & PL_WRITEABLE) {
619 		/* Someone crept in while we were busy */
620 		mutex_exit(p->p_lock);
621 		limfree(newlim);
622 		if (set_shared)
623 			p->p_limit->pl_flags |= PL_SHAREMOD;
624 		return;
625 	}
626 
627 	/*
628 	 * Since most accesses to p->p_limit aren't locked, we must not
629 	 * delete the old limit structure yet.
630 	 */
631 	newlim->pl_sv_limit = p->p_limit;
632 	newlim->pl_flags |= PL_WRITEABLE;
633 	if (set_shared)
634 		newlim->pl_flags |= PL_SHAREMOD;
635 	p->p_limit = newlim;
636 	mutex_exit(p->p_lock);
637 }
638 
639 void
640 limfree(struct plimit *lim)
641 {
642 	struct plimit *sv_lim;
643 
644 	do {
645 		if (atomic_dec_uint_nv(&lim->pl_refcnt) > 0)
646 			return;
647 		if (lim->pl_corename != defcorename)
648 			free(lim->pl_corename, M_TEMP);
649 		sv_lim = lim->pl_sv_limit;
650 		mutex_destroy(&lim->pl_lock);
651 		pool_cache_put(plimit_cache, lim);
652 	} while ((lim = sv_lim) != NULL);
653 }
654 
655 struct pstats *
656 pstatscopy(struct pstats *ps)
657 {
658 
659 	struct pstats *newps;
660 
661 	newps = pool_cache_get(pstats_cache, PR_WAITOK);
662 
663 	memset(&newps->pstat_startzero, 0,
664 	(unsigned) ((char *)&newps->pstat_endzero -
665 		    (char *)&newps->pstat_startzero));
666 	memcpy(&newps->pstat_startcopy, &ps->pstat_startcopy,
667 	((char *)&newps->pstat_endcopy -
668 	 (char *)&newps->pstat_startcopy));
669 
670 	return (newps);
671 
672 }
673 
674 void
675 pstatsfree(struct pstats *ps)
676 {
677 
678 	pool_cache_put(pstats_cache, ps);
679 }
680 
681 /*
682  * sysctl interface in five parts
683  */
684 
685 /*
686  * a routine for sysctl proc subtree helpers that need to pick a valid
687  * process by pid.
688  */
689 static int
690 sysctl_proc_findproc(struct lwp *l, struct proc **p2, pid_t pid)
691 {
692 	struct proc *ptmp;
693 	int error = 0;
694 
695 	if (pid == PROC_CURPROC)
696 		ptmp = l->l_proc;
697 	else if ((ptmp = pfind(pid)) == NULL)
698 		error = ESRCH;
699 
700 	*p2 = ptmp;
701 	return (error);
702 }
703 
704 /*
705  * sysctl helper routine for setting a process's specific corefile
706  * name.  picks the process based on the given pid and checks the
707  * correctness of the new value.
708  */
709 static int
710 sysctl_proc_corename(SYSCTLFN_ARGS)
711 {
712 	struct proc *ptmp;
713 	struct plimit *lim;
714 	int error = 0, len;
715 	char *cname;
716 	char *ocore;
717 	char *tmp;
718 	struct sysctlnode node;
719 
720 	/*
721 	 * is this all correct?
722 	 */
723 	if (namelen != 0)
724 		return (EINVAL);
725 	if (name[-1] != PROC_PID_CORENAME)
726 		return (EINVAL);
727 
728 	/*
729 	 * whom are we tweaking?
730 	 */
731 	error = sysctl_proc_findproc(l, &ptmp, (pid_t)name[-2]);
732 	if (error)
733 		return (error);
734 
735 	/* XXX-elad */
736 	error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE, ptmp,
737 	    KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENTRY), NULL, NULL);
738 	if (error)
739 		return (error);
740 
741 	if (newp == NULL) {
742 		error = kauth_authorize_process(l->l_cred,
743 		    KAUTH_PROCESS_CORENAME, ptmp,
744 		    KAUTH_ARG(KAUTH_REQ_PROCESS_CORENAME_GET), NULL, NULL);
745 		if (error)
746 			return (error);
747 	}
748 
749 	/*
750 	 * let them modify a temporary copy of the core name
751 	 */
752 	cname = PNBUF_GET();
753 	lim = ptmp->p_limit;
754 	mutex_enter(&lim->pl_lock);
755 	strlcpy(cname, lim->pl_corename, MAXPATHLEN);
756 	mutex_exit(&lim->pl_lock);
757 
758 	node = *rnode;
759 	node.sysctl_data = cname;
760 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
761 
762 	/*
763 	 * if that failed, or they have nothing new to say, or we've
764 	 * heard it before...
765 	 */
766 	if (error || newp == NULL)
767 		goto done;
768 	lim = ptmp->p_limit;
769 	mutex_enter(&lim->pl_lock);
770 	error = strcmp(cname, lim->pl_corename);
771 	mutex_exit(&lim->pl_lock);
772 	if (error == 0)
773 		/* Unchanged */
774 		goto done;
775 
776 	error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CORENAME,
777 	    ptmp, KAUTH_ARG(KAUTH_REQ_PROCESS_CORENAME_SET), cname, NULL);
778 	if (error)
779 		return (error);
780 
781 	/*
782 	 * no error yet and cname now has the new core name in it.
783 	 * let's see if it looks acceptable.  it must be either "core"
784 	 * or end in ".core" or "/core".
785 	 */
786 	len = strlen(cname);
787 	if (len < 4) {
788 		error = EINVAL;
789 	} else if (strcmp(cname + len - 4, "core") != 0) {
790 		error = EINVAL;
791 	} else if (len > 4 && cname[len - 5] != '/' && cname[len - 5] != '.') {
792 		error = EINVAL;
793 	}
794 	if (error != 0) {
795 		goto done;
796 	}
797 
798 	/*
799 	 * hmm...looks good.  now...where do we put it?
800 	 */
801 	tmp = malloc(len + 1, M_TEMP, M_WAITOK|M_CANFAIL);
802 	if (tmp == NULL) {
803 		error = ENOMEM;
804 		goto done;
805 	}
806 	memcpy(tmp, cname, len + 1);
807 
808 	lim_privatise(ptmp, false);
809 	lim = ptmp->p_limit;
810 	mutex_enter(&lim->pl_lock);
811 	ocore = lim->pl_corename;
812 	lim->pl_corename = tmp;
813 	mutex_exit(&lim->pl_lock);
814 	if (ocore != defcorename)
815 		free(ocore, M_TEMP);
816 
817 done:
818 	PNBUF_PUT(cname);
819 	return error;
820 }
821 
822 /*
823  * sysctl helper routine for checking/setting a process's stop flags,
824  * one for fork and one for exec.
825  */
826 static int
827 sysctl_proc_stop(SYSCTLFN_ARGS)
828 {
829 	struct proc *ptmp;
830 	int i, f, error = 0;
831 	struct sysctlnode node;
832 
833 	if (namelen != 0)
834 		return (EINVAL);
835 
836 	error = sysctl_proc_findproc(l, &ptmp, (pid_t)name[-2]);
837 	if (error)
838 		return (error);
839 
840 	/* XXX-elad */
841 	error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE, ptmp,
842 	    KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENTRY), NULL, NULL);
843 	if (error)
844 		return (error);
845 
846 	switch (rnode->sysctl_num) {
847 	case PROC_PID_STOPFORK:
848 		f = PS_STOPFORK;
849 		break;
850 	case PROC_PID_STOPEXEC:
851 		f = PS_STOPEXEC;
852 		break;
853 	case PROC_PID_STOPEXIT:
854 		f = PS_STOPEXIT;
855 		break;
856 	default:
857 		return (EINVAL);
858 	}
859 
860 	i = (ptmp->p_flag & f) ? 1 : 0;
861 	node = *rnode;
862 	node.sysctl_data = &i;
863 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
864 	if (error || newp == NULL)
865 		return (error);
866 
867 	mutex_enter(ptmp->p_lock);
868 	error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_STOPFLAG,
869 	    ptmp, KAUTH_ARG(f), NULL, NULL);
870 	if (!error) {
871 		if (i) {
872 			ptmp->p_sflag |= f;
873 		} else {
874 			ptmp->p_sflag &= ~f;
875 		}
876 	}
877 	mutex_exit(ptmp->p_lock);
878 
879 	return error;
880 }
881 
882 /*
883  * sysctl helper routine for a process's rlimits as exposed by sysctl.
884  */
885 static int
886 sysctl_proc_plimit(SYSCTLFN_ARGS)
887 {
888 	struct proc *ptmp;
889 	u_int limitno;
890 	int which, error = 0;
891         struct rlimit alim;
892 	struct sysctlnode node;
893 
894 	if (namelen != 0)
895 		return (EINVAL);
896 
897 	which = name[-1];
898 	if (which != PROC_PID_LIMIT_TYPE_SOFT &&
899 	    which != PROC_PID_LIMIT_TYPE_HARD)
900 		return (EINVAL);
901 
902 	limitno = name[-2] - 1;
903 	if (limitno >= RLIM_NLIMITS)
904 		return (EINVAL);
905 
906 	if (name[-3] != PROC_PID_LIMIT)
907 		return (EINVAL);
908 
909 	error = sysctl_proc_findproc(l, &ptmp, (pid_t)name[-4]);
910 	if (error)
911 		return (error);
912 
913 	/* XXX-elad */
914 	error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE, ptmp,
915 	    KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENTRY), NULL, NULL);
916 	if (error)
917 		return (error);
918 
919 	/* Check if we can view limits. */
920 	if (newp == NULL) {
921 		error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_RLIMIT,
922 		    ptmp, KAUTH_ARG(KAUTH_REQ_PROCESS_RLIMIT_GET), &alim,
923 		    KAUTH_ARG(which));
924 		if (error)
925 			return (error);
926 	}
927 
928 	node = *rnode;
929 	memcpy(&alim, &ptmp->p_rlimit[limitno], sizeof(alim));
930 	if (which == PROC_PID_LIMIT_TYPE_HARD)
931 		node.sysctl_data = &alim.rlim_max;
932 	else
933 		node.sysctl_data = &alim.rlim_cur;
934 
935 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
936 	if (error || newp == NULL)
937 		return (error);
938 
939 	return (dosetrlimit(l, ptmp, limitno, &alim));
940 }
941 
942 /*
943  * and finally, the actually glue that sticks it to the tree
944  */
945 SYSCTL_SETUP(sysctl_proc_setup, "sysctl proc subtree setup")
946 {
947 
948 	sysctl_createv(clog, 0, NULL, NULL,
949 		       CTLFLAG_PERMANENT,
950 		       CTLTYPE_NODE, "proc", NULL,
951 		       NULL, 0, NULL, 0,
952 		       CTL_PROC, CTL_EOL);
953 	sysctl_createv(clog, 0, NULL, NULL,
954 		       CTLFLAG_PERMANENT|CTLFLAG_ANYNUMBER,
955 		       CTLTYPE_NODE, "curproc",
956 		       SYSCTL_DESCR("Per-process settings"),
957 		       NULL, 0, NULL, 0,
958 		       CTL_PROC, PROC_CURPROC, CTL_EOL);
959 
960 	sysctl_createv(clog, 0, NULL, NULL,
961 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE,
962 		       CTLTYPE_STRING, "corename",
963 		       SYSCTL_DESCR("Core file name"),
964 		       sysctl_proc_corename, 0, NULL, MAXPATHLEN,
965 		       CTL_PROC, PROC_CURPROC, PROC_PID_CORENAME, CTL_EOL);
966 	sysctl_createv(clog, 0, NULL, NULL,
967 		       CTLFLAG_PERMANENT,
968 		       CTLTYPE_NODE, "rlimit",
969 		       SYSCTL_DESCR("Process limits"),
970 		       NULL, 0, NULL, 0,
971 		       CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, CTL_EOL);
972 
973 #define create_proc_plimit(s, n) do {					\
974 	sysctl_createv(clog, 0, NULL, NULL,				\
975 		       CTLFLAG_PERMANENT,				\
976 		       CTLTYPE_NODE, s,					\
977 		       SYSCTL_DESCR("Process " s " limits"),		\
978 		       NULL, 0, NULL, 0,				\
979 		       CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, n,	\
980 		       CTL_EOL);					\
981 	sysctl_createv(clog, 0, NULL, NULL,				\
982 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE, \
983 		       CTLTYPE_QUAD, "soft",				\
984 		       SYSCTL_DESCR("Process soft " s " limit"),	\
985 		       sysctl_proc_plimit, 0, NULL, 0,			\
986 		       CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, n,	\
987 		       PROC_PID_LIMIT_TYPE_SOFT, CTL_EOL);		\
988 	sysctl_createv(clog, 0, NULL, NULL,				\
989 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE, \
990 		       CTLTYPE_QUAD, "hard",				\
991 		       SYSCTL_DESCR("Process hard " s " limit"),	\
992 		       sysctl_proc_plimit, 0, NULL, 0,			\
993 		       CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, n,	\
994 		       PROC_PID_LIMIT_TYPE_HARD, CTL_EOL);		\
995 	} while (0/*CONSTCOND*/)
996 
997 	create_proc_plimit("cputime",		PROC_PID_LIMIT_CPU);
998 	create_proc_plimit("filesize",		PROC_PID_LIMIT_FSIZE);
999 	create_proc_plimit("datasize",		PROC_PID_LIMIT_DATA);
1000 	create_proc_plimit("stacksize",		PROC_PID_LIMIT_STACK);
1001 	create_proc_plimit("coredumpsize",	PROC_PID_LIMIT_CORE);
1002 	create_proc_plimit("memoryuse",		PROC_PID_LIMIT_RSS);
1003 	create_proc_plimit("memorylocked",	PROC_PID_LIMIT_MEMLOCK);
1004 	create_proc_plimit("maxproc",		PROC_PID_LIMIT_NPROC);
1005 	create_proc_plimit("descriptors",	PROC_PID_LIMIT_NOFILE);
1006 	create_proc_plimit("sbsize",		PROC_PID_LIMIT_SBSIZE);
1007 	create_proc_plimit("vmemoryuse",	PROC_PID_LIMIT_AS);
1008 
1009 #undef create_proc_plimit
1010 
1011 	sysctl_createv(clog, 0, NULL, NULL,
1012 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE,
1013 		       CTLTYPE_INT, "stopfork",
1014 		       SYSCTL_DESCR("Stop process at fork(2)"),
1015 		       sysctl_proc_stop, 0, NULL, 0,
1016 		       CTL_PROC, PROC_CURPROC, PROC_PID_STOPFORK, CTL_EOL);
1017 	sysctl_createv(clog, 0, NULL, NULL,
1018 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE,
1019 		       CTLTYPE_INT, "stopexec",
1020 		       SYSCTL_DESCR("Stop process at execve(2)"),
1021 		       sysctl_proc_stop, 0, NULL, 0,
1022 		       CTL_PROC, PROC_CURPROC, PROC_PID_STOPEXEC, CTL_EOL);
1023 	sysctl_createv(clog, 0, NULL, NULL,
1024 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE,
1025 		       CTLTYPE_INT, "stopexit",
1026 		       SYSCTL_DESCR("Stop process before completing exit"),
1027 		       sysctl_proc_stop, 0, NULL, 0,
1028 		       CTL_PROC, PROC_CURPROC, PROC_PID_STOPEXIT, CTL_EOL);
1029 }
1030