kern_resource.c revision 1.137.2.1
1 /* $NetBSD: kern_resource.c,v 1.137.2.1 2008/03/29 20:47:00 christos 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 1.137.2.1 2008/03/29 20:47:00 christos 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 SLIST_HEAD(uihashhead, uidinfo) *uihashtbl; 70 static u_long uihash; 71 72 #define UIHASH(uid) (&uihashtbl[(uid) & uihash]) 73 74 static pool_cache_t plimit_cache; 75 static pool_cache_t pstats_cache; 76 77 void 78 resource_init(void) 79 { 80 /* 81 * In case of MP system, SLIST_FOREACH would force a cache line 82 * write-back for every modified 'uidinfo', thus we try to keep the 83 * lists short. 84 */ 85 const u_int uihash_sz = (maxproc > 1 ? 1024 : 64); 86 87 plimit_cache = pool_cache_init(sizeof(struct plimit), 0, 0, 0, 88 "plimitpl", NULL, IPL_NONE, NULL, NULL, NULL); 89 pstats_cache = pool_cache_init(sizeof(struct pstats), 0, 0, 0, 90 "pstatspl", NULL, IPL_NONE, NULL, NULL, NULL); 91 uihashtbl = hashinit(uihash_sz, HASH_SLIST, M_PROC, M_WAITOK, &uihash); 92 } 93 94 /* 95 * Resource controls and accounting. 96 */ 97 98 int 99 sys_getpriority(struct lwp *l, const struct sys_getpriority_args *uap, 100 register_t *retval) 101 { 102 /* { 103 syscallarg(int) which; 104 syscallarg(id_t) who; 105 } */ 106 struct proc *curp = l->l_proc, *p; 107 int low = NZERO + PRIO_MAX + 1; 108 int who = SCARG(uap, who); 109 110 mutex_enter(&proclist_lock); 111 switch (SCARG(uap, which)) { 112 case PRIO_PROCESS: 113 if (who == 0) 114 p = curp; 115 else 116 p = p_find(who, PFIND_LOCKED); 117 if (p != NULL) 118 low = p->p_nice; 119 break; 120 121 case PRIO_PGRP: { 122 struct pgrp *pg; 123 124 if (who == 0) 125 pg = curp->p_pgrp; 126 else if ((pg = pg_find(who, PFIND_LOCKED)) == NULL) 127 break; 128 LIST_FOREACH(p, &pg->pg_members, p_pglist) { 129 if (p->p_nice < low) 130 low = p->p_nice; 131 } 132 break; 133 } 134 135 case PRIO_USER: 136 if (who == 0) 137 who = (int)kauth_cred_geteuid(l->l_cred); 138 PROCLIST_FOREACH(p, &allproc) { 139 mutex_enter(&p->p_mutex); 140 if (kauth_cred_geteuid(p->p_cred) == 141 (uid_t)who && p->p_nice < low) 142 low = p->p_nice; 143 mutex_exit(&p->p_mutex); 144 } 145 break; 146 147 default: 148 mutex_exit(&proclist_lock); 149 return (EINVAL); 150 } 151 mutex_exit(&proclist_lock); 152 153 if (low == NZERO + PRIO_MAX + 1) 154 return (ESRCH); 155 *retval = low - NZERO; 156 return (0); 157 } 158 159 /* ARGSUSED */ 160 int 161 sys_setpriority(struct lwp *l, const struct sys_setpriority_args *uap, 162 register_t *retval) 163 { 164 /* { 165 syscallarg(int) which; 166 syscallarg(id_t) who; 167 syscallarg(int) prio; 168 } */ 169 struct proc *curp = l->l_proc, *p; 170 int found = 0, error = 0; 171 int who = SCARG(uap, who); 172 173 mutex_enter(&proclist_lock); 174 switch (SCARG(uap, which)) { 175 case PRIO_PROCESS: 176 if (who == 0) 177 p = curp; 178 else 179 p = p_find(who, PFIND_LOCKED); 180 if (p != 0) { 181 mutex_enter(&p->p_mutex); 182 error = donice(l, p, SCARG(uap, prio)); 183 mutex_exit(&p->p_mutex); 184 } 185 found++; 186 break; 187 188 case PRIO_PGRP: { 189 struct pgrp *pg; 190 191 if (who == 0) 192 pg = curp->p_pgrp; 193 else if ((pg = pg_find(who, PFIND_LOCKED)) == NULL) 194 break; 195 LIST_FOREACH(p, &pg->pg_members, p_pglist) { 196 mutex_enter(&p->p_mutex); 197 error = donice(l, p, SCARG(uap, prio)); 198 mutex_exit(&p->p_mutex); 199 found++; 200 } 201 break; 202 } 203 204 case PRIO_USER: 205 if (who == 0) 206 who = (int)kauth_cred_geteuid(l->l_cred); 207 PROCLIST_FOREACH(p, &allproc) { 208 mutex_enter(&p->p_mutex); 209 if (kauth_cred_geteuid(p->p_cred) == 210 (uid_t)SCARG(uap, who)) { 211 error = donice(l, p, SCARG(uap, prio)); 212 found++; 213 } 214 mutex_exit(&p->p_mutex); 215 } 216 break; 217 218 default: 219 error = EINVAL; 220 break; 221 } 222 mutex_exit(&proclist_lock); 223 if (found == 0) 224 return (ESRCH); 225 return (error); 226 } 227 228 /* 229 * Renice a process. 230 * 231 * Call with the target process' credentials locked. 232 */ 233 int 234 donice(struct lwp *l, struct proc *chgp, int n) 235 { 236 kauth_cred_t cred = l->l_cred; 237 int onice; 238 239 KASSERT(mutex_owned(&chgp->p_mutex)); 240 241 if (n > PRIO_MAX) 242 n = PRIO_MAX; 243 if (n < PRIO_MIN) 244 n = PRIO_MIN; 245 n += NZERO; 246 onice = chgp->p_nice; 247 onice = chgp->p_nice; 248 249 again: 250 if (kauth_authorize_process(cred, KAUTH_PROCESS_NICE, chgp, 251 KAUTH_ARG(n), NULL, NULL)) 252 return (EACCES); 253 mutex_spin_enter(&chgp->p_smutex); 254 if (onice != chgp->p_nice) { 255 mutex_spin_exit(&chgp->p_smutex); 256 goto again; 257 } 258 sched_nice(chgp, n); 259 mutex_spin_exit(&chgp->p_smutex); 260 return (0); 261 } 262 263 /* ARGSUSED */ 264 int 265 sys_setrlimit(struct lwp *l, const struct sys_setrlimit_args *uap, 266 register_t *retval) 267 { 268 /* { 269 syscallarg(int) which; 270 syscallarg(const struct rlimit *) rlp; 271 } */ 272 int which = SCARG(uap, which); 273 struct rlimit alim; 274 int error; 275 276 error = copyin(SCARG(uap, rlp), &alim, sizeof(struct rlimit)); 277 if (error) 278 return (error); 279 return (dosetrlimit(l, l->l_proc, which, &alim)); 280 } 281 282 int 283 dosetrlimit(struct lwp *l, struct proc *p, int which, struct rlimit *limp) 284 { 285 struct rlimit *alimp; 286 int error; 287 288 if ((u_int)which >= RLIM_NLIMITS) 289 return (EINVAL); 290 291 if (limp->rlim_cur < 0 || limp->rlim_max < 0) 292 return (EINVAL); 293 294 if (limp->rlim_cur > limp->rlim_max) { 295 /* 296 * This is programming error. According to SUSv2, we should 297 * return error in this case. 298 */ 299 return (EINVAL); 300 } 301 302 alimp = &p->p_rlimit[which]; 303 /* if we don't change the value, no need to limcopy() */ 304 if (limp->rlim_cur == alimp->rlim_cur && 305 limp->rlim_max == alimp->rlim_max) 306 return 0; 307 308 error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_RLIMIT, 309 p, KAUTH_ARG(KAUTH_REQ_PROCESS_RLIMIT_SET), limp, KAUTH_ARG(which)); 310 if (error) 311 return (error); 312 313 lim_privatise(p, false); 314 /* p->p_limit is now unchangeable */ 315 alimp = &p->p_rlimit[which]; 316 317 switch (which) { 318 319 case RLIMIT_DATA: 320 if (limp->rlim_cur > maxdmap) 321 limp->rlim_cur = maxdmap; 322 if (limp->rlim_max > maxdmap) 323 limp->rlim_max = maxdmap; 324 break; 325 326 case RLIMIT_STACK: 327 if (limp->rlim_cur > maxsmap) 328 limp->rlim_cur = maxsmap; 329 if (limp->rlim_max > maxsmap) 330 limp->rlim_max = maxsmap; 331 332 /* 333 * Return EINVAL if the new stack size limit is lower than 334 * current usage. Otherwise, the process would get SIGSEGV the 335 * moment it would try to access anything on it's current stack. 336 * This conforms to SUSv2. 337 */ 338 if (limp->rlim_cur < p->p_vmspace->vm_ssize * PAGE_SIZE 339 || limp->rlim_max < p->p_vmspace->vm_ssize * PAGE_SIZE) { 340 return (EINVAL); 341 } 342 343 /* 344 * Stack is allocated to the max at exec time with 345 * only "rlim_cur" bytes accessible (In other words, 346 * allocates stack dividing two contiguous regions at 347 * "rlim_cur" bytes boundary). 348 * 349 * Since allocation is done in terms of page, roundup 350 * "rlim_cur" (otherwise, contiguous regions 351 * overlap). If stack limit is going up make more 352 * accessible, if going down make inaccessible. 353 */ 354 limp->rlim_cur = round_page(limp->rlim_cur); 355 if (limp->rlim_cur != alimp->rlim_cur) { 356 vaddr_t addr; 357 vsize_t size; 358 vm_prot_t prot; 359 360 if (limp->rlim_cur > alimp->rlim_cur) { 361 prot = VM_PROT_READ | VM_PROT_WRITE; 362 size = limp->rlim_cur - alimp->rlim_cur; 363 addr = (vaddr_t)p->p_vmspace->vm_minsaddr - 364 limp->rlim_cur; 365 } else { 366 prot = VM_PROT_NONE; 367 size = alimp->rlim_cur - limp->rlim_cur; 368 addr = (vaddr_t)p->p_vmspace->vm_minsaddr - 369 alimp->rlim_cur; 370 } 371 (void) uvm_map_protect(&p->p_vmspace->vm_map, 372 addr, addr+size, prot, false); 373 } 374 break; 375 376 case RLIMIT_NOFILE: 377 if (limp->rlim_cur > maxfiles) 378 limp->rlim_cur = maxfiles; 379 if (limp->rlim_max > maxfiles) 380 limp->rlim_max = maxfiles; 381 break; 382 383 case RLIMIT_NPROC: 384 if (limp->rlim_cur > maxproc) 385 limp->rlim_cur = maxproc; 386 if (limp->rlim_max > maxproc) 387 limp->rlim_max = maxproc; 388 break; 389 } 390 391 mutex_enter(&p->p_limit->pl_lock); 392 *alimp = *limp; 393 mutex_exit(&p->p_limit->pl_lock); 394 return (0); 395 } 396 397 /* ARGSUSED */ 398 int 399 sys_getrlimit(struct lwp *l, const struct sys_getrlimit_args *uap, 400 register_t *retval) 401 { 402 /* { 403 syscallarg(int) which; 404 syscallarg(struct rlimit *) rlp; 405 } */ 406 struct proc *p = l->l_proc; 407 int which = SCARG(uap, which); 408 struct rlimit rl; 409 410 if ((u_int)which >= RLIM_NLIMITS) 411 return (EINVAL); 412 413 mutex_enter(&p->p_mutex); 414 memcpy(&rl, &p->p_rlimit[which], sizeof(rl)); 415 mutex_exit(&p->p_mutex); 416 417 return copyout(&rl, SCARG(uap, rlp), sizeof(rl)); 418 } 419 420 /* 421 * Transform the running time and tick information in proc p into user, 422 * system, and interrupt time usage. 423 * 424 * Should be called with p->p_smutex held unless called from exit1(). 425 */ 426 void 427 calcru(struct proc *p, struct timeval *up, struct timeval *sp, 428 struct timeval *ip, struct timeval *rp) 429 { 430 uint64_t u, st, ut, it, tot; 431 struct lwp *l; 432 struct bintime tm; 433 struct timeval tv; 434 435 mutex_spin_enter(&p->p_stmutex); 436 st = p->p_sticks; 437 ut = p->p_uticks; 438 it = p->p_iticks; 439 mutex_spin_exit(&p->p_stmutex); 440 441 tm = p->p_rtime; 442 443 LIST_FOREACH(l, &p->p_lwps, l_sibling) { 444 lwp_lock(l); 445 bintime_add(&tm, &l->l_rtime); 446 if ((l->l_flag & LW_RUNNING) != 0) { 447 struct bintime diff; 448 /* 449 * Adjust for the current time slice. This is 450 * actually fairly important since the error 451 * here is on the order of a time quantum, 452 * which is much greater than the sampling 453 * error. 454 */ 455 binuptime(&diff); 456 bintime_sub(&diff, &l->l_stime); 457 bintime_add(&tm, &diff); 458 } 459 lwp_unlock(l); 460 } 461 462 tot = st + ut + it; 463 bintime2timeval(&tm, &tv); 464 u = (uint64_t)tv.tv_sec * 1000000ul + tv.tv_usec; 465 466 if (tot == 0) { 467 /* No ticks, so can't use to share time out, split 50-50 */ 468 st = ut = u / 2; 469 } else { 470 st = (u * st) / tot; 471 ut = (u * ut) / tot; 472 } 473 if (sp != NULL) { 474 sp->tv_sec = st / 1000000; 475 sp->tv_usec = st % 1000000; 476 } 477 if (up != NULL) { 478 up->tv_sec = ut / 1000000; 479 up->tv_usec = ut % 1000000; 480 } 481 if (ip != NULL) { 482 if (it != 0) 483 it = (u * it) / tot; 484 ip->tv_sec = it / 1000000; 485 ip->tv_usec = it % 1000000; 486 } 487 if (rp != NULL) { 488 *rp = tv; 489 } 490 } 491 492 /* ARGSUSED */ 493 int 494 sys___getrusage50(struct lwp *l, const struct sys___getrusage50_args *uap, 495 register_t *retval) 496 { 497 /* { 498 syscallarg(int) who; 499 syscallarg(struct rusage *) rusage; 500 } */ 501 struct rusage ru; 502 struct proc *p = l->l_proc; 503 504 switch (SCARG(uap, who)) { 505 case RUSAGE_SELF: 506 mutex_enter(&p->p_smutex); 507 memcpy(&ru, &p->p_stats->p_ru, sizeof(ru)); 508 calcru(p, &ru.ru_utime, &ru.ru_stime, NULL, NULL); 509 rulwps(p, &ru); 510 mutex_exit(&p->p_smutex); 511 break; 512 513 case RUSAGE_CHILDREN: 514 mutex_enter(&p->p_smutex); 515 memcpy(&ru, &p->p_stats->p_cru, sizeof(ru)); 516 mutex_exit(&p->p_smutex); 517 break; 518 519 default: 520 return EINVAL; 521 } 522 523 return copyout(&ru, SCARG(uap, rusage), sizeof(ru)); 524 } 525 526 void 527 ruadd(struct rusage *ru, struct rusage *ru2) 528 { 529 long *ip, *ip2; 530 int i; 531 532 timeradd(&ru->ru_utime, &ru2->ru_utime, &ru->ru_utime); 533 timeradd(&ru->ru_stime, &ru2->ru_stime, &ru->ru_stime); 534 if (ru->ru_maxrss < ru2->ru_maxrss) 535 ru->ru_maxrss = ru2->ru_maxrss; 536 ip = &ru->ru_first; ip2 = &ru2->ru_first; 537 for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--) 538 *ip++ += *ip2++; 539 } 540 541 void 542 rulwps(proc_t *p, struct rusage *ru) 543 { 544 lwp_t *l; 545 546 KASSERT(mutex_owned(&p->p_smutex)); 547 548 LIST_FOREACH(l, &p->p_lwps, l_sibling) { 549 ruadd(ru, &l->l_ru); 550 ru->ru_nvcsw += (l->l_ncsw - l->l_nivcsw); 551 ru->ru_nivcsw += l->l_nivcsw; 552 } 553 } 554 555 /* 556 * Make a copy of the plimit structure. 557 * We share these structures copy-on-write after fork, 558 * and copy when a limit is changed. 559 * 560 * Unfortunately (due to PL_SHAREMOD) it is possibly for the structure 561 * we are copying to change beneath our feet! 562 */ 563 struct plimit * 564 lim_copy(struct plimit *lim) 565 { 566 struct plimit *newlim; 567 char *corename; 568 size_t alen, len; 569 570 newlim = pool_cache_get(plimit_cache, PR_WAITOK); 571 mutex_init(&newlim->pl_lock, MUTEX_DEFAULT, IPL_NONE); 572 newlim->pl_flags = 0; 573 newlim->pl_refcnt = 1; 574 newlim->pl_sv_limit = NULL; 575 576 mutex_enter(&lim->pl_lock); 577 memcpy(newlim->pl_rlimit, lim->pl_rlimit, 578 sizeof(struct rlimit) * RLIM_NLIMITS); 579 580 alen = 0; 581 corename = NULL; 582 for (;;) { 583 if (lim->pl_corename == defcorename) { 584 newlim->pl_corename = defcorename; 585 break; 586 } 587 len = strlen(lim->pl_corename) + 1; 588 if (len <= alen) { 589 newlim->pl_corename = corename; 590 memcpy(corename, lim->pl_corename, len); 591 corename = NULL; 592 break; 593 } 594 mutex_exit(&lim->pl_lock); 595 if (corename != NULL) 596 free(corename, M_TEMP); 597 alen = len; 598 corename = malloc(alen, M_TEMP, M_WAITOK); 599 mutex_enter(&lim->pl_lock); 600 } 601 mutex_exit(&lim->pl_lock); 602 if (corename != NULL) 603 free(corename, M_TEMP); 604 return newlim; 605 } 606 607 void 608 lim_addref(struct plimit *lim) 609 { 610 atomic_inc_uint(&lim->pl_refcnt); 611 } 612 613 /* 614 * Give a process it's own private plimit structure. 615 * This will only be shared (in fork) if modifications are to be shared. 616 */ 617 void 618 lim_privatise(struct proc *p, bool set_shared) 619 { 620 struct plimit *lim, *newlim; 621 622 lim = p->p_limit; 623 if (lim->pl_flags & PL_WRITEABLE) { 624 if (set_shared) 625 lim->pl_flags |= PL_SHAREMOD; 626 return; 627 } 628 629 if (set_shared && lim->pl_flags & PL_SHAREMOD) 630 return; 631 632 newlim = lim_copy(lim); 633 634 mutex_enter(&p->p_mutex); 635 if (p->p_limit->pl_flags & PL_WRITEABLE) { 636 /* Someone crept in while we were busy */ 637 mutex_exit(&p->p_mutex); 638 limfree(newlim); 639 if (set_shared) 640 p->p_limit->pl_flags |= PL_SHAREMOD; 641 return; 642 } 643 644 /* 645 * Since most accesses to p->p_limit aren't locked, we must not 646 * delete the old limit structure yet. 647 */ 648 newlim->pl_sv_limit = p->p_limit; 649 newlim->pl_flags |= PL_WRITEABLE; 650 if (set_shared) 651 newlim->pl_flags |= PL_SHAREMOD; 652 p->p_limit = newlim; 653 mutex_exit(&p->p_mutex); 654 } 655 656 void 657 limfree(struct plimit *lim) 658 { 659 struct plimit *sv_lim; 660 661 do { 662 if (atomic_dec_uint_nv(&lim->pl_refcnt) > 0) 663 return; 664 if (lim->pl_corename != defcorename) 665 free(lim->pl_corename, M_TEMP); 666 sv_lim = lim->pl_sv_limit; 667 mutex_destroy(&lim->pl_lock); 668 pool_cache_put(plimit_cache, lim); 669 } while ((lim = sv_lim) != NULL); 670 } 671 672 struct pstats * 673 pstatscopy(struct pstats *ps) 674 { 675 676 struct pstats *newps; 677 678 newps = pool_cache_get(pstats_cache, PR_WAITOK); 679 680 memset(&newps->pstat_startzero, 0, 681 (unsigned) ((char *)&newps->pstat_endzero - 682 (char *)&newps->pstat_startzero)); 683 memcpy(&newps->pstat_startcopy, &ps->pstat_startcopy, 684 ((char *)&newps->pstat_endcopy - 685 (char *)&newps->pstat_startcopy)); 686 687 return (newps); 688 689 } 690 691 void 692 pstatsfree(struct pstats *ps) 693 { 694 695 pool_cache_put(pstats_cache, ps); 696 } 697 698 /* 699 * sysctl interface in five parts 700 */ 701 702 /* 703 * a routine for sysctl proc subtree helpers that need to pick a valid 704 * process by pid. 705 */ 706 static int 707 sysctl_proc_findproc(struct lwp *l, struct proc **p2, pid_t pid) 708 { 709 struct proc *ptmp; 710 int error = 0; 711 712 if (pid == PROC_CURPROC) 713 ptmp = l->l_proc; 714 else if ((ptmp = pfind(pid)) == NULL) 715 error = ESRCH; 716 717 *p2 = ptmp; 718 return (error); 719 } 720 721 /* 722 * sysctl helper routine for setting a process's specific corefile 723 * name. picks the process based on the given pid and checks the 724 * correctness of the new value. 725 */ 726 static int 727 sysctl_proc_corename(SYSCTLFN_ARGS) 728 { 729 struct proc *ptmp; 730 struct plimit *lim; 731 int error = 0, len; 732 char *cname; 733 char *ocore; 734 char *tmp; 735 struct sysctlnode node; 736 737 /* 738 * is this all correct? 739 */ 740 if (namelen != 0) 741 return (EINVAL); 742 if (name[-1] != PROC_PID_CORENAME) 743 return (EINVAL); 744 745 /* 746 * whom are we tweaking? 747 */ 748 error = sysctl_proc_findproc(l, &ptmp, (pid_t)name[-2]); 749 if (error) 750 return (error); 751 752 /* XXX-elad */ 753 error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE, ptmp, 754 KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENTRY), NULL, NULL); 755 if (error) 756 return (error); 757 758 if (newp == NULL) { 759 error = kauth_authorize_process(l->l_cred, 760 KAUTH_PROCESS_CORENAME, ptmp, 761 KAUTH_ARG(KAUTH_REQ_PROCESS_CORENAME_GET), NULL, NULL); 762 if (error) 763 return (error); 764 } 765 766 /* 767 * let them modify a temporary copy of the core name 768 */ 769 cname = PNBUF_GET(); 770 lim = ptmp->p_limit; 771 mutex_enter(&lim->pl_lock); 772 strlcpy(cname, lim->pl_corename, MAXPATHLEN); 773 mutex_exit(&lim->pl_lock); 774 775 node = *rnode; 776 node.sysctl_data = cname; 777 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 778 779 /* 780 * if that failed, or they have nothing new to say, or we've 781 * heard it before... 782 */ 783 if (error || newp == NULL) 784 goto done; 785 lim = ptmp->p_limit; 786 mutex_enter(&lim->pl_lock); 787 error = strcmp(cname, lim->pl_corename); 788 mutex_exit(&lim->pl_lock); 789 if (error == 0) 790 /* Unchanged */ 791 goto done; 792 793 error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CORENAME, 794 ptmp, KAUTH_ARG(KAUTH_REQ_PROCESS_CORENAME_SET), cname, NULL); 795 if (error) 796 return (error); 797 798 /* 799 * no error yet and cname now has the new core name in it. 800 * let's see if it looks acceptable. it must be either "core" 801 * or end in ".core" or "/core". 802 */ 803 len = strlen(cname); 804 if (len < 4) { 805 error = EINVAL; 806 } else if (strcmp(cname + len - 4, "core") != 0) { 807 error = EINVAL; 808 } else if (len > 4 && cname[len - 5] != '/' && cname[len - 5] != '.') { 809 error = EINVAL; 810 } 811 if (error != 0) { 812 goto done; 813 } 814 815 /* 816 * hmm...looks good. now...where do we put it? 817 */ 818 tmp = malloc(len + 1, M_TEMP, M_WAITOK|M_CANFAIL); 819 if (tmp == NULL) { 820 error = ENOMEM; 821 goto done; 822 } 823 memcpy(tmp, cname, len + 1); 824 825 lim_privatise(ptmp, false); 826 lim = ptmp->p_limit; 827 mutex_enter(&lim->pl_lock); 828 ocore = lim->pl_corename; 829 lim->pl_corename = tmp; 830 mutex_exit(&lim->pl_lock); 831 if (ocore != defcorename) 832 free(ocore, M_TEMP); 833 834 done: 835 PNBUF_PUT(cname); 836 return error; 837 } 838 839 /* 840 * sysctl helper routine for checking/setting a process's stop flags, 841 * one for fork and one for exec. 842 */ 843 static int 844 sysctl_proc_stop(SYSCTLFN_ARGS) 845 { 846 struct proc *ptmp; 847 int i, f, error = 0; 848 struct sysctlnode node; 849 850 if (namelen != 0) 851 return (EINVAL); 852 853 error = sysctl_proc_findproc(l, &ptmp, (pid_t)name[-2]); 854 if (error) 855 return (error); 856 857 /* XXX-elad */ 858 error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE, ptmp, 859 KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENTRY), NULL, NULL); 860 if (error) 861 return (error); 862 863 switch (rnode->sysctl_num) { 864 case PROC_PID_STOPFORK: 865 f = PS_STOPFORK; 866 break; 867 case PROC_PID_STOPEXEC: 868 f = PS_STOPEXEC; 869 break; 870 case PROC_PID_STOPEXIT: 871 f = PS_STOPEXIT; 872 break; 873 default: 874 return (EINVAL); 875 } 876 877 i = (ptmp->p_flag & f) ? 1 : 0; 878 node = *rnode; 879 node.sysctl_data = &i; 880 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 881 if (error || newp == NULL) 882 return (error); 883 884 mutex_enter(&ptmp->p_smutex); 885 error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_STOPFLAG, 886 ptmp, KAUTH_ARG(f), NULL, NULL); 887 if (error) 888 return (error); 889 if (i) 890 ptmp->p_sflag |= f; 891 else 892 ptmp->p_sflag &= ~f; 893 mutex_exit(&ptmp->p_smutex); 894 895 return (0); 896 } 897 898 /* 899 * sysctl helper routine for a process's rlimits as exposed by sysctl. 900 */ 901 static int 902 sysctl_proc_plimit(SYSCTLFN_ARGS) 903 { 904 struct proc *ptmp; 905 u_int limitno; 906 int which, error = 0; 907 struct rlimit alim; 908 struct sysctlnode node; 909 910 if (namelen != 0) 911 return (EINVAL); 912 913 which = name[-1]; 914 if (which != PROC_PID_LIMIT_TYPE_SOFT && 915 which != PROC_PID_LIMIT_TYPE_HARD) 916 return (EINVAL); 917 918 limitno = name[-2] - 1; 919 if (limitno >= RLIM_NLIMITS) 920 return (EINVAL); 921 922 if (name[-3] != PROC_PID_LIMIT) 923 return (EINVAL); 924 925 error = sysctl_proc_findproc(l, &ptmp, (pid_t)name[-4]); 926 if (error) 927 return (error); 928 929 /* XXX-elad */ 930 error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE, ptmp, 931 KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENTRY), NULL, NULL); 932 if (error) 933 return (error); 934 935 /* Check if we can view limits. */ 936 if (newp == NULL) { 937 error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_RLIMIT, 938 ptmp, KAUTH_ARG(KAUTH_REQ_PROCESS_RLIMIT_GET), &alim, 939 KAUTH_ARG(which)); 940 if (error) 941 return (error); 942 } 943 944 node = *rnode; 945 memcpy(&alim, &ptmp->p_rlimit[limitno], sizeof(alim)); 946 if (which == PROC_PID_LIMIT_TYPE_HARD) 947 node.sysctl_data = &alim.rlim_max; 948 else 949 node.sysctl_data = &alim.rlim_cur; 950 951 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 952 if (error || newp == NULL) 953 return (error); 954 955 return (dosetrlimit(l, ptmp, limitno, &alim)); 956 } 957 958 /* 959 * and finally, the actually glue that sticks it to the tree 960 */ 961 SYSCTL_SETUP(sysctl_proc_setup, "sysctl proc subtree setup") 962 { 963 964 sysctl_createv(clog, 0, NULL, NULL, 965 CTLFLAG_PERMANENT, 966 CTLTYPE_NODE, "proc", NULL, 967 NULL, 0, NULL, 0, 968 CTL_PROC, CTL_EOL); 969 sysctl_createv(clog, 0, NULL, NULL, 970 CTLFLAG_PERMANENT|CTLFLAG_ANYNUMBER, 971 CTLTYPE_NODE, "curproc", 972 SYSCTL_DESCR("Per-process settings"), 973 NULL, 0, NULL, 0, 974 CTL_PROC, PROC_CURPROC, CTL_EOL); 975 976 sysctl_createv(clog, 0, NULL, NULL, 977 CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE, 978 CTLTYPE_STRING, "corename", 979 SYSCTL_DESCR("Core file name"), 980 sysctl_proc_corename, 0, NULL, MAXPATHLEN, 981 CTL_PROC, PROC_CURPROC, PROC_PID_CORENAME, CTL_EOL); 982 sysctl_createv(clog, 0, NULL, NULL, 983 CTLFLAG_PERMANENT, 984 CTLTYPE_NODE, "rlimit", 985 SYSCTL_DESCR("Process limits"), 986 NULL, 0, NULL, 0, 987 CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, CTL_EOL); 988 989 #define create_proc_plimit(s, n) do { \ 990 sysctl_createv(clog, 0, NULL, NULL, \ 991 CTLFLAG_PERMANENT, \ 992 CTLTYPE_NODE, s, \ 993 SYSCTL_DESCR("Process " s " limits"), \ 994 NULL, 0, NULL, 0, \ 995 CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, n, \ 996 CTL_EOL); \ 997 sysctl_createv(clog, 0, NULL, NULL, \ 998 CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE, \ 999 CTLTYPE_QUAD, "soft", \ 1000 SYSCTL_DESCR("Process soft " s " limit"), \ 1001 sysctl_proc_plimit, 0, NULL, 0, \ 1002 CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, n, \ 1003 PROC_PID_LIMIT_TYPE_SOFT, CTL_EOL); \ 1004 sysctl_createv(clog, 0, NULL, NULL, \ 1005 CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE, \ 1006 CTLTYPE_QUAD, "hard", \ 1007 SYSCTL_DESCR("Process hard " s " limit"), \ 1008 sysctl_proc_plimit, 0, NULL, 0, \ 1009 CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, n, \ 1010 PROC_PID_LIMIT_TYPE_HARD, CTL_EOL); \ 1011 } while (0/*CONSTCOND*/) 1012 1013 create_proc_plimit("cputime", PROC_PID_LIMIT_CPU); 1014 create_proc_plimit("filesize", PROC_PID_LIMIT_FSIZE); 1015 create_proc_plimit("datasize", PROC_PID_LIMIT_DATA); 1016 create_proc_plimit("stacksize", PROC_PID_LIMIT_STACK); 1017 create_proc_plimit("coredumpsize", PROC_PID_LIMIT_CORE); 1018 create_proc_plimit("memoryuse", PROC_PID_LIMIT_RSS); 1019 create_proc_plimit("memorylocked", PROC_PID_LIMIT_MEMLOCK); 1020 create_proc_plimit("maxproc", PROC_PID_LIMIT_NPROC); 1021 create_proc_plimit("descriptors", PROC_PID_LIMIT_NOFILE); 1022 create_proc_plimit("sbsize", PROC_PID_LIMIT_SBSIZE); 1023 1024 #undef create_proc_plimit 1025 1026 sysctl_createv(clog, 0, NULL, NULL, 1027 CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE, 1028 CTLTYPE_INT, "stopfork", 1029 SYSCTL_DESCR("Stop process at fork(2)"), 1030 sysctl_proc_stop, 0, NULL, 0, 1031 CTL_PROC, PROC_CURPROC, PROC_PID_STOPFORK, CTL_EOL); 1032 sysctl_createv(clog, 0, NULL, NULL, 1033 CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE, 1034 CTLTYPE_INT, "stopexec", 1035 SYSCTL_DESCR("Stop process at execve(2)"), 1036 sysctl_proc_stop, 0, NULL, 0, 1037 CTL_PROC, PROC_CURPROC, PROC_PID_STOPEXEC, CTL_EOL); 1038 sysctl_createv(clog, 0, NULL, NULL, 1039 CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE, 1040 CTLTYPE_INT, "stopexit", 1041 SYSCTL_DESCR("Stop process before completing exit"), 1042 sysctl_proc_stop, 0, NULL, 0, 1043 CTL_PROC, PROC_CURPROC, PROC_PID_STOPEXIT, CTL_EOL); 1044 } 1045 1046 void 1047 uid_init(void) 1048 { 1049 1050 /* 1051 * Ensure that uid 0 is always in the user hash table, as 1052 * sbreserve() expects it available from interrupt context. 1053 */ 1054 (void)uid_find(0); 1055 } 1056 1057 struct uidinfo * 1058 uid_find(uid_t uid) 1059 { 1060 struct uidinfo *uip, *uip_first, *newuip; 1061 struct uihashhead *uipp; 1062 1063 uipp = UIHASH(uid); 1064 newuip = NULL; 1065 1066 /* 1067 * To make insertion atomic, abstraction of SLIST will be violated. 1068 */ 1069 uip_first = uipp->slh_first; 1070 again: 1071 SLIST_FOREACH(uip, uipp, ui_hash) { 1072 if (uip->ui_uid != uid) 1073 continue; 1074 if (newuip != NULL) 1075 kmem_free(newuip, sizeof(*newuip)); 1076 return uip; 1077 } 1078 if (newuip == NULL) 1079 newuip = kmem_zalloc(sizeof(*newuip), KM_SLEEP); 1080 newuip->ui_uid = uid; 1081 1082 /* 1083 * If atomic insert is unsuccessful, another thread might be 1084 * allocated this 'uid', thus full re-check is needed. 1085 */ 1086 newuip->ui_hash.sle_next = uip_first; 1087 membar_producer(); 1088 uip = atomic_cas_ptr(&uipp->slh_first, uip_first, newuip); 1089 if (uip != uip_first) { 1090 uip_first = uip; 1091 goto again; 1092 } 1093 1094 return newuip; 1095 } 1096 1097 /* 1098 * Change the count associated with number of processes 1099 * a given user is using. 1100 */ 1101 int 1102 chgproccnt(uid_t uid, int diff) 1103 { 1104 struct uidinfo *uip; 1105 long proccnt; 1106 1107 uip = uid_find(uid); 1108 proccnt = atomic_add_long_nv(&uip->ui_proccnt, diff); 1109 KASSERT(proccnt >= 0); 1110 return proccnt; 1111 } 1112 1113 int 1114 chgsbsize(struct uidinfo *uip, u_long *hiwat, u_long to, rlim_t xmax) 1115 { 1116 rlim_t nsb; 1117 const long diff = to - *hiwat; 1118 1119 nsb = atomic_add_long_nv((long *)&uip->ui_sbsize, diff); 1120 if (diff > 0 && nsb > xmax) { 1121 atomic_add_long((long *)&uip->ui_sbsize, -diff); 1122 return 0; 1123 } 1124 *hiwat = to; 1125 KASSERT(nsb >= 0); 1126 return 1; 1127 } 1128
Indexes created Sun Sep 21 20:09:37 GMT 2025