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 1.14 2003/08/26 21:09:02 rob 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/kernel.h> 50 #include <sys/resourcevar.h> 51 #include <sys/malloc.h> 52 #include <sys/proc.h> 53 #include <sys/time.h> 54 55 #include <vm/vm.h> 56 #include <vm/vm_param.h> 57 #include <sys/lock.h> 58 #include <vm/pmap.h> 59 #include <vm/vm_map.h> 60 61 static int donice (struct proc *chgp, int n); 62 63 static MALLOC_DEFINE(M_UIDINFO, "uidinfo", "uidinfo structures"); 64 #define UIHASH(uid) (&uihashtbl[(uid) & uihash]) 65 static LIST_HEAD(uihashhead, uidinfo) *uihashtbl; 66 static u_long uihash; /* size of hash table - 1 */ 67 68 static struct uidinfo *uicreate (uid_t uid); 69 static struct uidinfo *uilookup (uid_t uid); 70 71 /* 72 * Resource controls and accounting. 73 */ 74 75 int 76 getpriority(struct getpriority_args *uap) 77 { 78 struct proc *curp = curproc; 79 struct proc *p; 80 int low = PRIO_MAX + 1; 81 82 switch (uap->which) { 83 case PRIO_PROCESS: 84 if (uap->who == 0) 85 p = curp; 86 else 87 p = pfind(uap->who); 88 if (p == 0) 89 break; 90 if (!PRISON_CHECK(curp->p_ucred, p->p_ucred)) 91 break; 92 low = p->p_nice; 93 break; 94 95 case PRIO_PGRP: 96 { 97 struct pgrp *pg; 98 99 if (uap->who == 0) 100 pg = curp->p_pgrp; 101 else if ((pg = pgfind(uap->who)) == NULL) 102 break; 103 LIST_FOREACH(p, &pg->pg_members, p_pglist) { 104 if ((PRISON_CHECK(curp->p_ucred, p->p_ucred) && p->p_nice < low)) 105 low = p->p_nice; 106 } 107 break; 108 } 109 case PRIO_USER: 110 if (uap->who == 0) 111 uap->who = curp->p_ucred->cr_uid; 112 FOREACH_PROC_IN_SYSTEM(p) 113 if (PRISON_CHECK(curp->p_ucred, p->p_ucred) && 114 p->p_ucred->cr_uid == uap->who && 115 p->p_nice < low) 116 low = p->p_nice; 117 break; 118 119 default: 120 return (EINVAL); 121 } 122 if (low == PRIO_MAX + 1) 123 return (ESRCH); 124 uap->sysmsg_result = low; 125 return (0); 126 } 127 128 /* ARGSUSED */ 129 int 130 setpriority(struct setpriority_args *uap) 131 { 132 struct proc *curp = curproc; 133 struct proc *p; 134 int found = 0, error = 0; 135 136 switch (uap->which) { 137 138 case PRIO_PROCESS: 139 if (uap->who == 0) 140 p = curp; 141 else 142 p = pfind(uap->who); 143 if (p == 0) 144 break; 145 if (!PRISON_CHECK(curp->p_ucred, p->p_ucred)) 146 break; 147 error = donice(p, uap->prio); 148 found++; 149 break; 150 151 case PRIO_PGRP: 152 { 153 struct pgrp *pg; 154 155 if (uap->who == 0) 156 pg = curp->p_pgrp; 157 else if ((pg = pgfind(uap->who)) == NULL) 158 break; 159 LIST_FOREACH(p, &pg->pg_members, p_pglist) { 160 if (PRISON_CHECK(curp->p_ucred, p->p_ucred)) { 161 error = donice(p, uap->prio); 162 found++; 163 } 164 } 165 break; 166 } 167 case PRIO_USER: 168 if (uap->who == 0) 169 uap->who = curp->p_ucred->cr_uid; 170 FOREACH_PROC_IN_SYSTEM(p) 171 if (p->p_ucred->cr_uid == uap->who && 172 PRISON_CHECK(curp->p_ucred, p->p_ucred)) { 173 error = donice(p, uap->prio); 174 found++; 175 } 176 break; 177 178 default: 179 return (EINVAL); 180 } 181 if (found == 0) 182 return (ESRCH); 183 return (error); 184 } 185 186 static int 187 donice(struct proc *chgp, int n) 188 { 189 struct proc *curp = curproc; 190 struct ucred *cr = curp->p_ucred; 191 192 if (cr->cr_uid && cr->cr_ruid && 193 cr->cr_uid != chgp->p_ucred->cr_uid && 194 cr->cr_ruid != chgp->p_ucred->cr_uid) 195 return (EPERM); 196 if (n > PRIO_MAX) 197 n = PRIO_MAX; 198 if (n < PRIO_MIN) 199 n = PRIO_MIN; 200 if (n < chgp->p_nice && suser_cred(cr, 0)) 201 return (EACCES); 202 chgp->p_nice = n; 203 (void)resetpriority(chgp); 204 return (0); 205 } 206 207 /* 208 * Set realtime priority 209 */ 210 /* ARGSUSED */ 211 int 212 rtprio(struct rtprio_args *uap) 213 { 214 struct proc *curp = curproc; 215 struct proc *p; 216 struct ucred *cr = curp->p_ucred; 217 struct rtprio rtp; 218 int error; 219 220 error = copyin(uap->rtp, &rtp, sizeof(struct rtprio)); 221 if (error) 222 return (error); 223 224 if (uap->pid == 0) 225 p = curp; 226 else 227 p = pfind(uap->pid); 228 229 if (p == 0) 230 return (ESRCH); 231 232 switch (uap->function) { 233 case RTP_LOOKUP: 234 return (copyout(&p->p_rtprio, uap->rtp, sizeof(struct rtprio))); 235 case RTP_SET: 236 if (cr->cr_uid && cr->cr_ruid && 237 cr->cr_uid != p->p_ucred->cr_uid && 238 cr->cr_ruid != p->p_ucred->cr_uid) 239 return (EPERM); 240 /* disallow setting rtprio in most cases if not superuser */ 241 if (suser_cred(cr, 0)) { 242 /* can't set someone else's */ 243 if (uap->pid) 244 return (EPERM); 245 /* can't set realtime priority */ 246 /* 247 * Realtime priority has to be restricted for reasons which should be 248 * obvious. However, for idle priority, there is a potential for 249 * system deadlock if an idleprio process gains a lock on a resource 250 * that other processes need (and the idleprio process can't run 251 * due to a CPU-bound normal process). Fix me! XXX 252 */ 253 if (RTP_PRIO_IS_REALTIME(rtp.type)) 254 return (EPERM); 255 } 256 switch (rtp.type) { 257 #ifdef RTP_PRIO_FIFO 258 case RTP_PRIO_FIFO: 259 #endif 260 case RTP_PRIO_REALTIME: 261 case RTP_PRIO_NORMAL: 262 case RTP_PRIO_IDLE: 263 if (rtp.prio > RTP_PRIO_MAX) 264 return (EINVAL); 265 p->p_rtprio = rtp; 266 return (0); 267 default: 268 return (EINVAL); 269 } 270 271 default: 272 return (EINVAL); 273 } 274 } 275 276 #if defined(COMPAT_43) || defined(COMPAT_SUNOS) 277 /* ARGSUSED */ 278 int 279 osetrlimit(struct osetrlimit_args *uap) 280 { 281 struct orlimit olim; 282 struct rlimit lim; 283 int error; 284 285 if ((error = 286 copyin((caddr_t)uap->rlp, (caddr_t)&olim, sizeof(struct orlimit)))) 287 return (error); 288 lim.rlim_cur = olim.rlim_cur; 289 lim.rlim_max = olim.rlim_max; 290 return (dosetrlimit(uap->which, &lim)); 291 } 292 293 /* ARGSUSED */ 294 int 295 ogetrlimit(struct ogetrlimit_args *uap) 296 { 297 struct proc *p = curproc; 298 struct orlimit olim; 299 300 if (uap->which >= RLIM_NLIMITS) 301 return (EINVAL); 302 olim.rlim_cur = p->p_rlimit[uap->which].rlim_cur; 303 if (olim.rlim_cur == -1) 304 olim.rlim_cur = 0x7fffffff; 305 olim.rlim_max = p->p_rlimit[uap->which].rlim_max; 306 if (olim.rlim_max == -1) 307 olim.rlim_max = 0x7fffffff; 308 return (copyout((caddr_t)&olim, (caddr_t)uap->rlp, sizeof(olim))); 309 } 310 #endif /* COMPAT_43 || COMPAT_SUNOS */ 311 312 /* ARGSUSED */ 313 int 314 setrlimit(struct __setrlimit_args *uap) 315 { 316 struct rlimit alim; 317 int error; 318 319 if ((error = 320 copyin((caddr_t)uap->rlp, (caddr_t)&alim, sizeof (struct rlimit)))) 321 return (error); 322 return (dosetrlimit(uap->which, &alim)); 323 } 324 325 int 326 dosetrlimit(u_int which, struct rlimit *limp) 327 { 328 struct proc *p = curproc; 329 struct rlimit *alimp; 330 int error; 331 332 if (which >= RLIM_NLIMITS) 333 return (EINVAL); 334 alimp = &p->p_rlimit[which]; 335 336 /* 337 * Preserve historical bugs by treating negative limits as unsigned. 338 */ 339 if (limp->rlim_cur < 0) 340 limp->rlim_cur = RLIM_INFINITY; 341 if (limp->rlim_max < 0) 342 limp->rlim_max = RLIM_INFINITY; 343 344 if (limp->rlim_cur > alimp->rlim_max || 345 limp->rlim_max > alimp->rlim_max) 346 if ((error = suser_cred(p->p_ucred, PRISON_ROOT))) 347 return (error); 348 if (limp->rlim_cur > limp->rlim_max) 349 limp->rlim_cur = limp->rlim_max; 350 if (p->p_limit->p_refcnt > 1 && 351 (p->p_limit->p_lflags & PL_SHAREMOD) == 0) { 352 p->p_limit->p_refcnt--; 353 p->p_limit = limcopy(p->p_limit); 354 alimp = &p->p_rlimit[which]; 355 } 356 357 switch (which) { 358 359 case RLIMIT_CPU: 360 if (limp->rlim_cur > RLIM_INFINITY / (rlim_t)1000000) 361 p->p_limit->p_cpulimit = RLIM_INFINITY; 362 else 363 p->p_limit->p_cpulimit = 364 (rlim_t)1000000 * limp->rlim_cur; 365 break; 366 case RLIMIT_DATA: 367 if (limp->rlim_cur > maxdsiz) 368 limp->rlim_cur = maxdsiz; 369 if (limp->rlim_max > maxdsiz) 370 limp->rlim_max = maxdsiz; 371 break; 372 373 case RLIMIT_STACK: 374 if (limp->rlim_cur > maxssiz) 375 limp->rlim_cur = maxssiz; 376 if (limp->rlim_max > maxssiz) 377 limp->rlim_max = maxssiz; 378 /* 379 * Stack is allocated to the max at exec time with only 380 * "rlim_cur" bytes accessible. If stack limit is going 381 * up make more accessible, if going down make inaccessible. 382 */ 383 if (limp->rlim_cur != alimp->rlim_cur) { 384 vm_offset_t addr; 385 vm_size_t size; 386 vm_prot_t prot; 387 388 if (limp->rlim_cur > alimp->rlim_cur) { 389 prot = VM_PROT_ALL; 390 size = limp->rlim_cur - alimp->rlim_cur; 391 addr = USRSTACK - limp->rlim_cur; 392 } else { 393 prot = VM_PROT_NONE; 394 size = alimp->rlim_cur - limp->rlim_cur; 395 addr = USRSTACK - alimp->rlim_cur; 396 } 397 addr = trunc_page(addr); 398 size = round_page(size); 399 (void) vm_map_protect(&p->p_vmspace->vm_map, 400 addr, addr+size, prot, FALSE); 401 } 402 break; 403 404 case RLIMIT_NOFILE: 405 if (limp->rlim_cur > maxfilesperproc) 406 limp->rlim_cur = maxfilesperproc; 407 if (limp->rlim_max > maxfilesperproc) 408 limp->rlim_max = maxfilesperproc; 409 break; 410 411 case RLIMIT_NPROC: 412 if (limp->rlim_cur > maxprocperuid) 413 limp->rlim_cur = maxprocperuid; 414 if (limp->rlim_max > maxprocperuid) 415 limp->rlim_max = maxprocperuid; 416 if (limp->rlim_cur < 1) 417 limp->rlim_cur = 1; 418 if (limp->rlim_max < 1) 419 limp->rlim_max = 1; 420 break; 421 } 422 *alimp = *limp; 423 return (0); 424 } 425 426 /* ARGSUSED */ 427 int 428 getrlimit(struct __getrlimit_args *uap) 429 { 430 struct proc *p = curproc; 431 432 if (uap->which >= RLIM_NLIMITS) 433 return (EINVAL); 434 return (copyout((caddr_t)&p->p_rlimit[uap->which], (caddr_t)uap->rlp, 435 sizeof (struct rlimit))); 436 } 437 438 /* 439 * Transform the running time and tick information in proc p into user, 440 * system, and interrupt time usage. 441 * 442 * Since we are limited to statclock tick granularity this is a statisical 443 * calculation which will be correct over the long haul, but should not be 444 * expected to measure fine grained deltas. 445 */ 446 void 447 calcru(p, up, sp, ip) 448 struct proc *p; 449 struct timeval *up; 450 struct timeval *sp; 451 struct timeval *ip; 452 { 453 struct thread *td = p->p_thread; 454 int s; 455 456 /* 457 * Calculate at the statclock level. YYY if the thread is owned by 458 * another cpu we need to forward the request to the other cpu, or 459 * have a token to interlock the information. 460 */ 461 s = splstatclock(); 462 up->tv_sec = td->td_uticks / 1000000; 463 up->tv_usec = td->td_uticks % 1000000; 464 sp->tv_sec = td->td_sticks / 1000000; 465 sp->tv_usec = td->td_sticks % 1000000; 466 if (ip != NULL) { 467 ip->tv_sec = td->td_iticks / 1000000; 468 ip->tv_usec = td->td_iticks % 1000000; 469 } 470 splx(s); 471 } 472 473 /* ARGSUSED */ 474 int 475 getrusage(struct getrusage_args *uap) 476 { 477 struct proc *p = curproc; 478 struct rusage *rup; 479 480 switch (uap->who) { 481 482 case RUSAGE_SELF: 483 rup = &p->p_stats->p_ru; 484 calcru(p, &rup->ru_utime, &rup->ru_stime, NULL); 485 break; 486 487 case RUSAGE_CHILDREN: 488 rup = &p->p_stats->p_cru; 489 break; 490 491 default: 492 return (EINVAL); 493 } 494 return (copyout((caddr_t)rup, (caddr_t)uap->rusage, 495 sizeof (struct rusage))); 496 } 497 498 void 499 ruadd(ru, ru2) 500 struct rusage *ru, *ru2; 501 { 502 long *ip, *ip2; 503 int i; 504 505 timevaladd(&ru->ru_utime, &ru2->ru_utime); 506 timevaladd(&ru->ru_stime, &ru2->ru_stime); 507 if (ru->ru_maxrss < ru2->ru_maxrss) 508 ru->ru_maxrss = ru2->ru_maxrss; 509 ip = &ru->ru_first; ip2 = &ru2->ru_first; 510 for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--) 511 *ip++ += *ip2++; 512 } 513 514 /* 515 * Make a copy of the plimit structure. 516 * We share these structures copy-on-write after fork, 517 * and copy when a limit is changed. 518 */ 519 struct plimit * 520 limcopy(lim) 521 struct plimit *lim; 522 { 523 struct plimit *copy; 524 525 MALLOC(copy, struct plimit *, sizeof(struct plimit), 526 M_SUBPROC, M_WAITOK); 527 bcopy(lim->pl_rlimit, copy->pl_rlimit, sizeof(struct plimit)); 528 copy->p_lflags = 0; 529 copy->p_refcnt = 1; 530 return (copy); 531 } 532 533 /* 534 * Find the uidinfo structure for a uid. This structure is used to 535 * track the total resource consumption (process count, socket buffer 536 * size, etc.) for the uid and impose limits. 537 */ 538 void 539 uihashinit() 540 { 541 uihashtbl = hashinit(maxproc / 16, M_UIDINFO, &uihash); 542 } 543 544 static struct uidinfo * 545 uilookup(uid) 546 uid_t uid; 547 { 548 struct uihashhead *uipp; 549 struct uidinfo *uip; 550 551 uipp = UIHASH(uid); 552 LIST_FOREACH(uip, uipp, ui_hash) 553 if (uip->ui_uid == uid) 554 break; 555 556 return (uip); 557 } 558 559 static struct uidinfo * 560 uicreate(uid) 561 uid_t uid; 562 { 563 struct uidinfo *uip, *norace; 564 565 MALLOC(uip, struct uidinfo *, sizeof(*uip), M_UIDINFO, M_NOWAIT); 566 if (uip == NULL) { 567 MALLOC(uip, struct uidinfo *, sizeof(*uip), M_UIDINFO, M_WAITOK); 568 /* 569 * if we M_WAITOK we must look afterwards or risk 570 * redundant entries 571 */ 572 norace = uilookup(uid); 573 if (norace != NULL) { 574 FREE(uip, M_UIDINFO); 575 return (norace); 576 } 577 } 578 LIST_INSERT_HEAD(UIHASH(uid), uip, ui_hash); 579 uip->ui_uid = uid; 580 uip->ui_proccnt = 0; 581 uip->ui_sbsize = 0; 582 uip->ui_ref = 0; 583 return (uip); 584 } 585 586 struct uidinfo * 587 uifind(uid) 588 uid_t uid; 589 { 590 struct uidinfo *uip; 591 592 uip = uilookup(uid); 593 if (uip == NULL) 594 uip = uicreate(uid); 595 uip->ui_ref++; 596 return (uip); 597 } 598 599 int 600 uifree(uip) 601 struct uidinfo *uip; 602 { 603 604 if (--uip->ui_ref == 0) { 605 if (uip->ui_sbsize != 0) 606 /* XXX no %qd in kernel. Truncate. */ 607 printf("freeing uidinfo: uid = %d, sbsize = %ld\n", 608 uip->ui_uid, (long)uip->ui_sbsize); 609 if (uip->ui_proccnt != 0) 610 printf("freeing uidinfo: uid = %d, proccnt = %ld\n", 611 uip->ui_uid, uip->ui_proccnt); 612 LIST_REMOVE(uip, ui_hash); 613 FREE(uip, M_UIDINFO); 614 return (1); 615 } 616 return (0); 617 } 618 619 /* 620 * Change the count associated with number of processes 621 * a given user is using. When 'max' is 0, don't enforce a limit 622 */ 623 int 624 chgproccnt(uip, diff, max) 625 struct uidinfo *uip; 626 int diff; 627 int max; 628 { 629 /* don't allow them to exceed max, but allow subtraction */ 630 if (diff > 0 && uip->ui_proccnt + diff > max && max != 0) 631 return (0); 632 uip->ui_proccnt += diff; 633 if (uip->ui_proccnt < 0) 634 printf("negative proccnt for uid = %d\n", uip->ui_uid); 635 return (1); 636 } 637 638 /* 639 * Change the total socket buffer size a user has used. 640 */ 641 int 642 chgsbsize(uip, hiwat, to, max) 643 struct uidinfo *uip; 644 u_long *hiwat; 645 u_long to; 646 rlim_t max; 647 { 648 rlim_t new; 649 int s; 650 651 s = splnet(); 652 new = uip->ui_sbsize + to - *hiwat; 653 /* don't allow them to exceed max, but allow subtraction */ 654 if (to > *hiwat && new > max) { 655 splx(s); 656 return (0); 657 } 658 uip->ui_sbsize = new; 659 *hiwat = to; 660 if (uip->ui_sbsize < 0) 661 printf("negative sbsize for uid = %d\n", uip->ui_uid); 662 splx(s); 663 return (1); 664 } 665