1 /* $NetBSD: kern_resource.c,v 1.195 2023/10/04 20:28:06 ad 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 1.195 2023/10/04 20:28:06 ad 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/kmem.h> 48 #include <sys/namei.h> 49 #include <sys/pool.h> 50 #include <sys/proc.h> 51 #include <sys/sysctl.h> 52 #include <sys/timevar.h> 53 #include <sys/kauth.h> 54 #include <sys/atomic.h> 55 #include <sys/mount.h> 56 #include <sys/syscallargs.h> 57 #include <sys/atomic.h> 58 59 #include <uvm/uvm_extern.h> 60 61 /* 62 * Maximum process data and stack limits. 63 * They are variables so they are patchable. 64 */ 65 rlim_t maxdmap = MAXDSIZ; 66 rlim_t maxsmap = MAXSSIZ; 67 68 static kauth_listener_t resource_listener; 69 static struct sysctllog *proc_sysctllog; 70 71 static int donice(struct lwp *, struct proc *, int); 72 static void sysctl_proc_setup(void); 73 74 static int 75 resource_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, 76 void *arg0, void *arg1, void *arg2, void *arg3) 77 { 78 struct proc *p; 79 int result; 80 81 result = KAUTH_RESULT_DEFER; 82 p = arg0; 83 84 switch (action) { 85 case KAUTH_PROCESS_NICE: 86 if (kauth_cred_geteuid(cred) != kauth_cred_geteuid(p->p_cred) && 87 kauth_cred_getuid(cred) != kauth_cred_geteuid(p->p_cred)) { 88 break; 89 } 90 91 if ((u_long)arg1 >= p->p_nice) 92 result = KAUTH_RESULT_ALLOW; 93 94 break; 95 96 case KAUTH_PROCESS_RLIMIT: { 97 enum kauth_process_req req; 98 99 req = (enum kauth_process_req)(uintptr_t)arg1; 100 101 switch (req) { 102 case KAUTH_REQ_PROCESS_RLIMIT_GET: 103 result = KAUTH_RESULT_ALLOW; 104 break; 105 106 case KAUTH_REQ_PROCESS_RLIMIT_SET: { 107 struct rlimit *new_rlimit; 108 u_long which; 109 110 if ((p != curlwp->l_proc) && 111 (proc_uidmatch(cred, p->p_cred) != 0)) 112 break; 113 114 new_rlimit = arg2; 115 which = (u_long)arg3; 116 117 if (new_rlimit->rlim_max <= p->p_rlimit[which].rlim_max) 118 result = KAUTH_RESULT_ALLOW; 119 120 break; 121 } 122 123 default: 124 break; 125 } 126 127 break; 128 } 129 130 default: 131 break; 132 } 133 134 return result; 135 } 136 137 void 138 resource_init(void) 139 { 140 141 resource_listener = kauth_listen_scope(KAUTH_SCOPE_PROCESS, 142 resource_listener_cb, NULL); 143 144 sysctl_proc_setup(); 145 } 146 147 /* 148 * Resource controls and accounting. 149 */ 150 151 int 152 sys_getpriority(struct lwp *l, const struct sys_getpriority_args *uap, 153 register_t *retval) 154 { 155 /* { 156 syscallarg(int) which; 157 syscallarg(id_t) who; 158 } */ 159 struct proc *curp = l->l_proc, *p; 160 id_t who = SCARG(uap, who); 161 int low = NZERO + PRIO_MAX + 1; 162 163 mutex_enter(&proc_lock); 164 switch (SCARG(uap, which)) { 165 case PRIO_PROCESS: 166 p = who ? proc_find(who) : curp; 167 if (p != NULL) 168 low = p->p_nice; 169 break; 170 171 case PRIO_PGRP: { 172 struct pgrp *pg; 173 174 if (who == 0) 175 pg = curp->p_pgrp; 176 else if ((pg = pgrp_find(who)) == NULL) 177 break; 178 LIST_FOREACH(p, &pg->pg_members, p_pglist) { 179 if (p->p_nice < low) 180 low = p->p_nice; 181 } 182 break; 183 } 184 185 case PRIO_USER: 186 if (who == 0) 187 who = (int)kauth_cred_geteuid(l->l_cred); 188 PROCLIST_FOREACH(p, &allproc) { 189 mutex_enter(p->p_lock); 190 if (kauth_cred_geteuid(p->p_cred) == 191 (uid_t)who && p->p_nice < low) 192 low = p->p_nice; 193 mutex_exit(p->p_lock); 194 } 195 break; 196 197 default: 198 mutex_exit(&proc_lock); 199 return EINVAL; 200 } 201 mutex_exit(&proc_lock); 202 203 if (low == NZERO + PRIO_MAX + 1) { 204 return ESRCH; 205 } 206 *retval = low - NZERO; 207 return 0; 208 } 209 210 int 211 sys_setpriority(struct lwp *l, const struct sys_setpriority_args *uap, 212 register_t *retval) 213 { 214 /* { 215 syscallarg(int) which; 216 syscallarg(id_t) who; 217 syscallarg(int) prio; 218 } */ 219 struct proc *curp = l->l_proc, *p; 220 id_t who = SCARG(uap, who); 221 int found = 0, error = 0; 222 223 mutex_enter(&proc_lock); 224 switch (SCARG(uap, which)) { 225 case PRIO_PROCESS: 226 p = who ? proc_find(who) : curp; 227 if (p != NULL) { 228 mutex_enter(p->p_lock); 229 found++; 230 error = donice(l, p, SCARG(uap, prio)); 231 mutex_exit(p->p_lock); 232 } 233 break; 234 235 case PRIO_PGRP: { 236 struct pgrp *pg; 237 238 if (who == 0) 239 pg = curp->p_pgrp; 240 else if ((pg = pgrp_find(who)) == NULL) 241 break; 242 LIST_FOREACH(p, &pg->pg_members, p_pglist) { 243 mutex_enter(p->p_lock); 244 found++; 245 error = donice(l, p, SCARG(uap, prio)); 246 mutex_exit(p->p_lock); 247 if (error) 248 break; 249 } 250 break; 251 } 252 253 case PRIO_USER: 254 if (who == 0) 255 who = (int)kauth_cred_geteuid(l->l_cred); 256 PROCLIST_FOREACH(p, &allproc) { 257 mutex_enter(p->p_lock); 258 if (kauth_cred_geteuid(p->p_cred) == 259 (uid_t)SCARG(uap, who)) { 260 found++; 261 error = donice(l, p, SCARG(uap, prio)); 262 } 263 mutex_exit(p->p_lock); 264 if (error) 265 break; 266 } 267 break; 268 269 default: 270 mutex_exit(&proc_lock); 271 return EINVAL; 272 } 273 mutex_exit(&proc_lock); 274 275 return (found == 0) ? ESRCH : error; 276 } 277 278 /* 279 * Renice a process. 280 * 281 * Call with the target process' credentials locked. 282 */ 283 static int 284 donice(struct lwp *l, struct proc *chgp, int n) 285 { 286 kauth_cred_t cred = l->l_cred; 287 288 KASSERT(mutex_owned(chgp->p_lock)); 289 290 if (kauth_cred_geteuid(cred) && kauth_cred_getuid(cred) && 291 kauth_cred_geteuid(cred) != kauth_cred_geteuid(chgp->p_cred) && 292 kauth_cred_getuid(cred) != kauth_cred_geteuid(chgp->p_cred)) 293 return EPERM; 294 295 if (n > PRIO_MAX) { 296 n = PRIO_MAX; 297 } 298 if (n < PRIO_MIN) { 299 n = PRIO_MIN; 300 } 301 n += NZERO; 302 303 if (kauth_authorize_process(cred, KAUTH_PROCESS_NICE, chgp, 304 KAUTH_ARG(n), NULL, NULL)) { 305 return EACCES; 306 } 307 308 sched_nice(chgp, n); 309 return 0; 310 } 311 312 int 313 sys_setrlimit(struct lwp *l, const struct sys_setrlimit_args *uap, 314 register_t *retval) 315 { 316 /* { 317 syscallarg(int) which; 318 syscallarg(const struct rlimit *) rlp; 319 } */ 320 int error, which = SCARG(uap, which); 321 struct rlimit alim; 322 323 error = copyin(SCARG(uap, rlp), &alim, sizeof(struct rlimit)); 324 if (error) { 325 return error; 326 } 327 return dosetrlimit(l, l->l_proc, which, &alim); 328 } 329 330 int 331 dosetrlimit(struct lwp *l, struct proc *p, int which, struct rlimit *limp) 332 { 333 struct rlimit *alimp; 334 int error; 335 336 if ((u_int)which >= RLIM_NLIMITS) 337 return EINVAL; 338 339 if (limp->rlim_cur > limp->rlim_max) { 340 /* 341 * This is programming error. According to SUSv2, we should 342 * return error in this case. 343 */ 344 return EINVAL; 345 } 346 347 alimp = &p->p_rlimit[which]; 348 /* if we don't change the value, no need to limcopy() */ 349 if (limp->rlim_cur == alimp->rlim_cur && 350 limp->rlim_max == alimp->rlim_max) 351 return 0; 352 353 error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_RLIMIT, 354 p, KAUTH_ARG(KAUTH_REQ_PROCESS_RLIMIT_SET), limp, KAUTH_ARG(which)); 355 if (error) 356 return error; 357 358 lim_privatise(p); 359 /* p->p_limit is now unchangeable */ 360 alimp = &p->p_rlimit[which]; 361 362 switch (which) { 363 364 case RLIMIT_DATA: 365 if (limp->rlim_cur > maxdmap) 366 limp->rlim_cur = maxdmap; 367 if (limp->rlim_max > maxdmap) 368 limp->rlim_max = maxdmap; 369 break; 370 371 case RLIMIT_STACK: 372 if (limp->rlim_cur > maxsmap) 373 limp->rlim_cur = maxsmap; 374 if (limp->rlim_max > maxsmap) 375 limp->rlim_max = maxsmap; 376 377 /* 378 * Return EINVAL if the new stack size limit is lower than 379 * current usage. Otherwise, the process would get SIGSEGV the 380 * moment it would try to access anything on its current stack. 381 * This conforms to SUSv2. 382 */ 383 if (btoc(limp->rlim_cur) < p->p_vmspace->vm_ssize || 384 btoc(limp->rlim_max) < p->p_vmspace->vm_ssize) { 385 return EINVAL; 386 } 387 388 /* 389 * Stack is allocated to the max at exec time with 390 * only "rlim_cur" bytes accessible (In other words, 391 * allocates stack dividing two contiguous regions at 392 * "rlim_cur" bytes boundary). 393 * 394 * Since allocation is done in terms of page, roundup 395 * "rlim_cur" (otherwise, contiguous regions 396 * overlap). If stack limit is going up make more 397 * accessible, if going down make inaccessible. 398 */ 399 limp->rlim_max = round_page(limp->rlim_max); 400 limp->rlim_cur = round_page(limp->rlim_cur); 401 if (limp->rlim_cur != alimp->rlim_cur) { 402 vaddr_t addr; 403 vsize_t size; 404 vm_prot_t prot; 405 char *base, *tmp; 406 407 base = p->p_vmspace->vm_minsaddr; 408 if (limp->rlim_cur > alimp->rlim_cur) { 409 prot = VM_PROT_READ | VM_PROT_WRITE; 410 size = limp->rlim_cur - alimp->rlim_cur; 411 tmp = STACK_GROW(base, alimp->rlim_cur); 412 } else { 413 prot = VM_PROT_NONE; 414 size = alimp->rlim_cur - limp->rlim_cur; 415 tmp = STACK_GROW(base, limp->rlim_cur); 416 } 417 addr = (vaddr_t)STACK_ALLOC(tmp, size); 418 (void) uvm_map_protect(&p->p_vmspace->vm_map, 419 addr, addr + size, prot, false); 420 } 421 break; 422 423 case RLIMIT_NOFILE: 424 if (limp->rlim_cur > maxfiles) 425 limp->rlim_cur = maxfiles; 426 if (limp->rlim_max > maxfiles) 427 limp->rlim_max = maxfiles; 428 break; 429 430 case RLIMIT_NPROC: 431 if (limp->rlim_cur > maxproc) 432 limp->rlim_cur = maxproc; 433 if (limp->rlim_max > maxproc) 434 limp->rlim_max = maxproc; 435 break; 436 437 case RLIMIT_NTHR: 438 if (limp->rlim_cur > maxlwp) 439 limp->rlim_cur = maxlwp; 440 if (limp->rlim_max > maxlwp) 441 limp->rlim_max = maxlwp; 442 break; 443 } 444 445 mutex_enter(&p->p_limit->pl_lock); 446 *alimp = *limp; 447 mutex_exit(&p->p_limit->pl_lock); 448 return 0; 449 } 450 451 int 452 sys_getrlimit(struct lwp *l, const struct sys_getrlimit_args *uap, 453 register_t *retval) 454 { 455 /* { 456 syscallarg(int) which; 457 syscallarg(struct rlimit *) rlp; 458 } */ 459 struct proc *p = l->l_proc; 460 int which = SCARG(uap, which); 461 struct rlimit rl; 462 463 if ((u_int)which >= RLIM_NLIMITS) 464 return EINVAL; 465 466 mutex_enter(p->p_lock); 467 memcpy(&rl, &p->p_rlimit[which], sizeof(rl)); 468 mutex_exit(p->p_lock); 469 470 return copyout(&rl, SCARG(uap, rlp), sizeof(rl)); 471 } 472 473 void 474 addrulwp(struct lwp *l, struct bintime *tm) 475 { 476 477 lwp_lock(l); 478 bintime_add(tm, &l->l_rtime); 479 if ((l->l_pflag & LP_RUNNING) != 0 && 480 (l->l_pflag & (LP_INTR | LP_TIMEINTR)) != LP_INTR) { 481 struct bintime diff; 482 /* 483 * Adjust for the current time slice. This is 484 * actually fairly important since the error 485 * here is on the order of a time quantum, 486 * which is much greater than the sampling 487 * error. 488 */ 489 binuptime(&diff); 490 membar_consumer(); /* for softint_dispatch() */ 491 bintime_sub(&diff, &l->l_stime); 492 bintime_add(tm, &diff); 493 } 494 lwp_unlock(l); 495 } 496 497 /* 498 * Transform the running time and tick information in proc p into user, 499 * system, and interrupt time usage. 500 * 501 * Should be called with p->p_lock held unless called from exit1(). 502 */ 503 void 504 calcru(struct proc *p, struct timeval *up, struct timeval *sp, 505 struct timeval *ip, struct timeval *rp) 506 { 507 uint64_t u, st, ut, it, tot, dt; 508 struct lwp *l; 509 struct bintime tm; 510 struct timeval tv; 511 512 KASSERT(p->p_stat == SDEAD || mutex_owned(p->p_lock)); 513 514 mutex_spin_enter(&p->p_stmutex); 515 st = p->p_sticks; 516 ut = p->p_uticks; 517 it = p->p_iticks; 518 mutex_spin_exit(&p->p_stmutex); 519 520 tm = p->p_rtime; 521 522 LIST_FOREACH(l, &p->p_lwps, l_sibling) { 523 addrulwp(l, &tm); 524 } 525 526 tot = st + ut + it; 527 bintime2timeval(&tm, &tv); 528 u = (uint64_t)tv.tv_sec * 1000000ul + tv.tv_usec; 529 530 if (tot == 0) { 531 /* No ticks, so can't use to share time out, split 50-50 */ 532 st = ut = u / 2; 533 } else { 534 st = (u * st) / tot; 535 ut = (u * ut) / tot; 536 } 537 538 /* 539 * Try to avoid lying to the users (too much) 540 * 541 * Of course, user/sys time are based on sampling (ie: statistics) 542 * so that would be impossible, but convincing the mark 543 * that we have used less ?time this call than we had 544 * last time, is beyond reasonable... (the con fails!) 545 * 546 * Note that since actual used time cannot decrease, either 547 * utime or stime (or both) must be greater now than last time 548 * (or both the same) - if one seems to have decreased, hold 549 * it constant and steal the necessary bump from the other 550 * which must have increased. 551 */ 552 if (p->p_xutime > ut) { 553 dt = p->p_xutime - ut; 554 st -= uimin(dt, st); 555 ut = p->p_xutime; 556 } else if (p->p_xstime > st) { 557 dt = p->p_xstime - st; 558 ut -= uimin(dt, ut); 559 st = p->p_xstime; 560 } 561 562 if (sp != NULL) { 563 p->p_xstime = st; 564 sp->tv_sec = st / 1000000; 565 sp->tv_usec = st % 1000000; 566 } 567 if (up != NULL) { 568 p->p_xutime = ut; 569 up->tv_sec = ut / 1000000; 570 up->tv_usec = ut % 1000000; 571 } 572 if (ip != NULL) { 573 if (it != 0) /* it != 0 --> tot != 0 */ 574 it = (u * it) / tot; 575 ip->tv_sec = it / 1000000; 576 ip->tv_usec = it % 1000000; 577 } 578 if (rp != NULL) { 579 *rp = tv; 580 } 581 } 582 583 int 584 sys___getrusage50(struct lwp *l, const struct sys___getrusage50_args *uap, 585 register_t *retval) 586 { 587 /* { 588 syscallarg(int) who; 589 syscallarg(struct rusage *) rusage; 590 } */ 591 int error; 592 struct rusage ru; 593 struct proc *p = l->l_proc; 594 595 error = getrusage1(p, SCARG(uap, who), &ru); 596 if (error != 0) 597 return error; 598 599 return copyout(&ru, SCARG(uap, rusage), sizeof(ru)); 600 } 601 602 int 603 getrusage1(struct proc *p, int who, struct rusage *ru) 604 { 605 606 switch (who) { 607 case RUSAGE_SELF: 608 mutex_enter(p->p_lock); 609 ruspace(p); 610 memcpy(ru, &p->p_stats->p_ru, sizeof(*ru)); 611 calcru(p, &ru->ru_utime, &ru->ru_stime, NULL, NULL); 612 rulwps(p, ru); 613 mutex_exit(p->p_lock); 614 break; 615 case RUSAGE_CHILDREN: 616 mutex_enter(p->p_lock); 617 memcpy(ru, &p->p_stats->p_cru, sizeof(*ru)); 618 mutex_exit(p->p_lock); 619 break; 620 default: 621 return EINVAL; 622 } 623 624 return 0; 625 } 626 627 void 628 ruspace(struct proc *p) 629 { 630 struct vmspace *vm = p->p_vmspace; 631 struct rusage *ru = &p->p_stats->p_ru; 632 633 ru->ru_ixrss = vm->vm_tsize << (PAGE_SHIFT - 10); 634 ru->ru_idrss = vm->vm_dsize << (PAGE_SHIFT - 10); 635 ru->ru_isrss = vm->vm_ssize << (PAGE_SHIFT - 10); 636 #ifdef __HAVE_NO_PMAP_STATS 637 /* We don't keep track of the max so we get the current */ 638 ru->ru_maxrss = vm_resident_count(vm) << (PAGE_SHIFT - 10); 639 #else 640 ru->ru_maxrss = vm->vm_rssmax << (PAGE_SHIFT - 10); 641 #endif 642 } 643 644 void 645 ruadd(struct rusage *ru, struct rusage *ru2) 646 { 647 long *ip, *ip2; 648 int i; 649 650 timeradd(&ru->ru_utime, &ru2->ru_utime, &ru->ru_utime); 651 timeradd(&ru->ru_stime, &ru2->ru_stime, &ru->ru_stime); 652 if (ru->ru_maxrss < ru2->ru_maxrss) 653 ru->ru_maxrss = ru2->ru_maxrss; 654 ip = &ru->ru_first; ip2 = &ru2->ru_first; 655 for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--) 656 *ip++ += *ip2++; 657 } 658 659 void 660 rulwps(proc_t *p, struct rusage *ru) 661 { 662 lwp_t *l; 663 664 KASSERT(mutex_owned(p->p_lock)); 665 666 LIST_FOREACH(l, &p->p_lwps, l_sibling) { 667 ruadd(ru, &l->l_ru); 668 } 669 } 670 671 /* 672 * lim_copy: make a copy of the plimit structure. 673 * 674 * We use copy-on-write after fork, and copy when a limit is changed. 675 */ 676 struct plimit * 677 lim_copy(struct plimit *lim) 678 { 679 struct plimit *newlim; 680 char *corename; 681 size_t alen, len; 682 683 newlim = kmem_alloc(sizeof(*newlim), KM_SLEEP); 684 mutex_init(&newlim->pl_lock, MUTEX_DEFAULT, IPL_NONE); 685 newlim->pl_writeable = false; 686 newlim->pl_refcnt = 1; 687 newlim->pl_sv_limit = NULL; 688 689 mutex_enter(&lim->pl_lock); 690 memcpy(newlim->pl_rlimit, lim->pl_rlimit, 691 sizeof(struct rlimit) * RLIM_NLIMITS); 692 693 /* 694 * Note: the common case is a use of default core name. 695 */ 696 alen = 0; 697 corename = NULL; 698 for (;;) { 699 if (lim->pl_corename == defcorename) { 700 newlim->pl_corename = defcorename; 701 newlim->pl_cnlen = 0; 702 break; 703 } 704 len = lim->pl_cnlen; 705 if (len == alen) { 706 newlim->pl_corename = corename; 707 newlim->pl_cnlen = len; 708 memcpy(corename, lim->pl_corename, len); 709 corename = NULL; 710 break; 711 } 712 mutex_exit(&lim->pl_lock); 713 if (corename) { 714 kmem_free(corename, alen); 715 } 716 alen = len; 717 corename = kmem_alloc(alen, KM_SLEEP); 718 mutex_enter(&lim->pl_lock); 719 } 720 mutex_exit(&lim->pl_lock); 721 722 if (corename) { 723 kmem_free(corename, alen); 724 } 725 return newlim; 726 } 727 728 void 729 lim_addref(struct plimit *lim) 730 { 731 atomic_inc_uint(&lim->pl_refcnt); 732 } 733 734 /* 735 * lim_privatise: give a process its own private plimit structure. 736 */ 737 void 738 lim_privatise(proc_t *p) 739 { 740 struct plimit *lim = p->p_limit, *newlim; 741 742 if (lim->pl_writeable) { 743 return; 744 } 745 746 newlim = lim_copy(lim); 747 748 mutex_enter(p->p_lock); 749 if (p->p_limit->pl_writeable) { 750 /* Other thread won the race. */ 751 mutex_exit(p->p_lock); 752 lim_free(newlim); 753 return; 754 } 755 756 /* 757 * Since p->p_limit can be accessed without locked held, 758 * old limit structure must not be deleted yet. 759 */ 760 newlim->pl_sv_limit = p->p_limit; 761 newlim->pl_writeable = true; 762 p->p_limit = newlim; 763 mutex_exit(p->p_lock); 764 } 765 766 void 767 lim_setcorename(proc_t *p, char *name, size_t len) 768 { 769 struct plimit *lim; 770 char *oname; 771 size_t olen; 772 773 lim_privatise(p); 774 lim = p->p_limit; 775 776 mutex_enter(&lim->pl_lock); 777 oname = lim->pl_corename; 778 olen = lim->pl_cnlen; 779 lim->pl_corename = name; 780 lim->pl_cnlen = len; 781 mutex_exit(&lim->pl_lock); 782 783 if (oname != defcorename) { 784 kmem_free(oname, olen); 785 } 786 } 787 788 void 789 lim_free(struct plimit *lim) 790 { 791 struct plimit *sv_lim; 792 793 do { 794 membar_release(); 795 if (atomic_dec_uint_nv(&lim->pl_refcnt) > 0) { 796 return; 797 } 798 membar_acquire(); 799 if (lim->pl_corename != defcorename) { 800 kmem_free(lim->pl_corename, lim->pl_cnlen); 801 } 802 sv_lim = lim->pl_sv_limit; 803 mutex_destroy(&lim->pl_lock); 804 kmem_free(lim, sizeof(*lim)); 805 } while ((lim = sv_lim) != NULL); 806 } 807 808 struct pstats * 809 pstatscopy(struct pstats *ps) 810 { 811 struct pstats *nps; 812 size_t len; 813 814 nps = kmem_alloc(sizeof(*nps), KM_SLEEP); 815 816 len = (char *)&nps->pstat_endzero - (char *)&nps->pstat_startzero; 817 memset(&nps->pstat_startzero, 0, len); 818 819 len = (char *)&nps->pstat_endcopy - (char *)&nps->pstat_startcopy; 820 memcpy(&nps->pstat_startcopy, &ps->pstat_startcopy, len); 821 822 return nps; 823 } 824 825 void 826 pstatsfree(struct pstats *ps) 827 { 828 829 kmem_free(ps, sizeof(*ps)); 830 } 831 832 /* 833 * sysctl_proc_findproc: a routine for sysctl proc subtree helpers that 834 * need to pick a valid process by PID. 835 * 836 * => Hold a reference on the process, on success. 837 */ 838 static int 839 sysctl_proc_findproc(lwp_t *l, pid_t pid, proc_t **p2) 840 { 841 proc_t *p; 842 int error; 843 844 if (pid == PROC_CURPROC) { 845 p = l->l_proc; 846 } else { 847 mutex_enter(&proc_lock); 848 p = proc_find(pid); 849 if (p == NULL) { 850 mutex_exit(&proc_lock); 851 return ESRCH; 852 } 853 } 854 error = rw_tryenter(&p->p_reflock, RW_READER) ? 0 : EBUSY; 855 if (pid != PROC_CURPROC) { 856 mutex_exit(&proc_lock); 857 } 858 *p2 = p; 859 return error; 860 } 861 862 /* 863 * sysctl_proc_paxflags: helper routine to get process's paxctl flags 864 */ 865 static int 866 sysctl_proc_paxflags(SYSCTLFN_ARGS) 867 { 868 struct proc *p; 869 struct sysctlnode node; 870 int paxflags; 871 int error; 872 873 /* First, validate the request. */ 874 if (namelen != 0 || name[-1] != PROC_PID_PAXFLAGS) 875 return EINVAL; 876 877 /* Find the process. Hold a reference (p_reflock), if found. */ 878 error = sysctl_proc_findproc(l, (pid_t)name[-2], &p); 879 if (error) 880 return error; 881 882 /* XXX-elad */ 883 error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE, p, 884 KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENTRY), NULL, NULL); 885 if (error) { 886 rw_exit(&p->p_reflock); 887 return error; 888 } 889 890 /* Retrieve the limits. */ 891 node = *rnode; 892 paxflags = p->p_pax; 893 node.sysctl_data = &paxflags; 894 895 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 896 897 /* If attempting to write new value, it's an error */ 898 if (error == 0 && newp != NULL) 899 error = EACCES; 900 901 rw_exit(&p->p_reflock); 902 return error; 903 } 904 905 /* 906 * sysctl_proc_corename: helper routine to get or set the core file name 907 * for a process specified by PID. 908 */ 909 static int 910 sysctl_proc_corename(SYSCTLFN_ARGS) 911 { 912 struct proc *p; 913 struct plimit *lim; 914 char *cnbuf, *cname; 915 struct sysctlnode node; 916 size_t len; 917 int error; 918 919 /* First, validate the request. */ 920 if (namelen != 0 || name[-1] != PROC_PID_CORENAME) 921 return EINVAL; 922 923 /* Find the process. Hold a reference (p_reflock), if found. */ 924 error = sysctl_proc_findproc(l, (pid_t)name[-2], &p); 925 if (error) 926 return error; 927 928 /* XXX-elad */ 929 error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE, p, 930 KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENTRY), NULL, NULL); 931 if (error) { 932 rw_exit(&p->p_reflock); 933 return error; 934 } 935 936 cnbuf = PNBUF_GET(); 937 938 if (oldp) { 939 /* Get case: copy the core name into the buffer. */ 940 error = kauth_authorize_process(l->l_cred, 941 KAUTH_PROCESS_CORENAME, p, 942 KAUTH_ARG(KAUTH_REQ_PROCESS_CORENAME_GET), NULL, NULL); 943 if (error) { 944 goto done; 945 } 946 lim = p->p_limit; 947 mutex_enter(&lim->pl_lock); 948 strlcpy(cnbuf, lim->pl_corename, MAXPATHLEN); 949 mutex_exit(&lim->pl_lock); 950 } 951 952 node = *rnode; 953 node.sysctl_data = cnbuf; 954 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 955 956 /* Return if error, or if caller is only getting the core name. */ 957 if (error || newp == NULL) { 958 goto done; 959 } 960 961 /* 962 * Set case. Check permission and then validate new core name. 963 * It must be either "core", "/core", or end in ".core". 964 */ 965 error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CORENAME, 966 p, KAUTH_ARG(KAUTH_REQ_PROCESS_CORENAME_SET), cnbuf, NULL); 967 if (error) { 968 goto done; 969 } 970 len = strlen(cnbuf); 971 if ((len < 4 || strcmp(cnbuf + len - 4, "core") != 0) || 972 (len > 4 && cnbuf[len - 5] != '/' && cnbuf[len - 5] != '.')) { 973 error = EINVAL; 974 goto done; 975 } 976 977 /* Allocate, copy and set the new core name for plimit structure. */ 978 cname = kmem_alloc(++len, KM_NOSLEEP); 979 if (cname == NULL) { 980 error = ENOMEM; 981 goto done; 982 } 983 memcpy(cname, cnbuf, len); 984 lim_setcorename(p, cname, len); 985 done: 986 rw_exit(&p->p_reflock); 987 PNBUF_PUT(cnbuf); 988 return error; 989 } 990 991 /* 992 * sysctl_proc_stop: helper routine for checking/setting the stop flags. 993 */ 994 static int 995 sysctl_proc_stop(SYSCTLFN_ARGS) 996 { 997 struct proc *p; 998 int isset, flag, error = 0; 999 struct sysctlnode node; 1000 1001 if (namelen != 0) 1002 return EINVAL; 1003 1004 /* Find the process. Hold a reference (p_reflock), if found. */ 1005 error = sysctl_proc_findproc(l, (pid_t)name[-2], &p); 1006 if (error) 1007 return error; 1008 1009 /* XXX-elad */ 1010 error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE, p, 1011 KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENTRY), NULL, NULL); 1012 if (error) { 1013 goto out; 1014 } 1015 1016 /* Determine the flag. */ 1017 switch (rnode->sysctl_num) { 1018 case PROC_PID_STOPFORK: 1019 flag = PS_STOPFORK; 1020 break; 1021 case PROC_PID_STOPEXEC: 1022 flag = PS_STOPEXEC; 1023 break; 1024 case PROC_PID_STOPEXIT: 1025 flag = PS_STOPEXIT; 1026 break; 1027 default: 1028 error = EINVAL; 1029 goto out; 1030 } 1031 isset = (p->p_flag & flag) ? 1 : 0; 1032 node = *rnode; 1033 node.sysctl_data = &isset; 1034 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 1035 1036 /* Return if error, or if callers is only getting the flag. */ 1037 if (error || newp == NULL) { 1038 goto out; 1039 } 1040 1041 /* Check if caller can set the flags. */ 1042 error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_STOPFLAG, 1043 p, KAUTH_ARG(flag), NULL, NULL); 1044 if (error) { 1045 goto out; 1046 } 1047 mutex_enter(p->p_lock); 1048 if (isset) { 1049 p->p_sflag |= flag; 1050 } else { 1051 p->p_sflag &= ~flag; 1052 } 1053 mutex_exit(p->p_lock); 1054 out: 1055 rw_exit(&p->p_reflock); 1056 return error; 1057 } 1058 1059 /* 1060 * sysctl_proc_plimit: helper routine to get/set rlimits of a process. 1061 */ 1062 static int 1063 sysctl_proc_plimit(SYSCTLFN_ARGS) 1064 { 1065 struct proc *p; 1066 u_int limitno; 1067 int which, error = 0; 1068 struct rlimit alim; 1069 struct sysctlnode node; 1070 1071 if (namelen != 0) 1072 return EINVAL; 1073 1074 which = name[-1]; 1075 if (which != PROC_PID_LIMIT_TYPE_SOFT && 1076 which != PROC_PID_LIMIT_TYPE_HARD) 1077 return EINVAL; 1078 1079 limitno = name[-2] - 1; 1080 if (limitno >= RLIM_NLIMITS) 1081 return EINVAL; 1082 1083 if (name[-3] != PROC_PID_LIMIT) 1084 return EINVAL; 1085 1086 /* Find the process. Hold a reference (p_reflock), if found. */ 1087 error = sysctl_proc_findproc(l, (pid_t)name[-4], &p); 1088 if (error) 1089 return error; 1090 1091 /* XXX-elad */ 1092 error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE, p, 1093 KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENTRY), NULL, NULL); 1094 if (error) 1095 goto out; 1096 1097 /* Check if caller can retrieve the limits. */ 1098 if (newp == NULL) { 1099 error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_RLIMIT, 1100 p, KAUTH_ARG(KAUTH_REQ_PROCESS_RLIMIT_GET), &alim, 1101 KAUTH_ARG(which)); 1102 if (error) 1103 goto out; 1104 } 1105 1106 /* Retrieve the limits. */ 1107 node = *rnode; 1108 memcpy(&alim, &p->p_rlimit[limitno], sizeof(alim)); 1109 if (which == PROC_PID_LIMIT_TYPE_HARD) { 1110 node.sysctl_data = &alim.rlim_max; 1111 } else { 1112 node.sysctl_data = &alim.rlim_cur; 1113 } 1114 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 1115 1116 /* Return if error, or if we are only retrieving the limits. */ 1117 if (error || newp == NULL) { 1118 goto out; 1119 } 1120 error = dosetrlimit(l, p, limitno, &alim); 1121 out: 1122 rw_exit(&p->p_reflock); 1123 return error; 1124 } 1125 1126 /* 1127 * Setup sysctl nodes. 1128 */ 1129 static void 1130 sysctl_proc_setup(void) 1131 { 1132 1133 sysctl_createv(&proc_sysctllog, 0, NULL, NULL, 1134 CTLFLAG_PERMANENT|CTLFLAG_ANYNUMBER, 1135 CTLTYPE_NODE, "curproc", 1136 SYSCTL_DESCR("Per-process settings"), 1137 NULL, 0, NULL, 0, 1138 CTL_PROC, PROC_CURPROC, CTL_EOL); 1139 1140 sysctl_createv(&proc_sysctllog, 0, NULL, NULL, 1141 CTLFLAG_PERMANENT|CTLFLAG_READONLY, 1142 CTLTYPE_INT, "paxflags", 1143 SYSCTL_DESCR("Process PAX control flags"), 1144 sysctl_proc_paxflags, 0, NULL, 0, 1145 CTL_PROC, PROC_CURPROC, PROC_PID_PAXFLAGS, CTL_EOL); 1146 1147 sysctl_createv(&proc_sysctllog, 0, NULL, NULL, 1148 CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE, 1149 CTLTYPE_STRING, "corename", 1150 SYSCTL_DESCR("Core file name"), 1151 sysctl_proc_corename, 0, NULL, MAXPATHLEN, 1152 CTL_PROC, PROC_CURPROC, PROC_PID_CORENAME, CTL_EOL); 1153 sysctl_createv(&proc_sysctllog, 0, NULL, NULL, 1154 CTLFLAG_PERMANENT, 1155 CTLTYPE_NODE, "rlimit", 1156 SYSCTL_DESCR("Process limits"), 1157 NULL, 0, NULL, 0, 1158 CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, CTL_EOL); 1159 1160 #define create_proc_plimit(s, n) do { \ 1161 sysctl_createv(&proc_sysctllog, 0, NULL, NULL, \ 1162 CTLFLAG_PERMANENT, \ 1163 CTLTYPE_NODE, s, \ 1164 SYSCTL_DESCR("Process " s " limits"), \ 1165 NULL, 0, NULL, 0, \ 1166 CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, n, \ 1167 CTL_EOL); \ 1168 sysctl_createv(&proc_sysctllog, 0, NULL, NULL, \ 1169 CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE, \ 1170 CTLTYPE_QUAD, "soft", \ 1171 SYSCTL_DESCR("Process soft " s " limit"), \ 1172 sysctl_proc_plimit, 0, NULL, 0, \ 1173 CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, n, \ 1174 PROC_PID_LIMIT_TYPE_SOFT, CTL_EOL); \ 1175 sysctl_createv(&proc_sysctllog, 0, NULL, NULL, \ 1176 CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE, \ 1177 CTLTYPE_QUAD, "hard", \ 1178 SYSCTL_DESCR("Process hard " s " limit"), \ 1179 sysctl_proc_plimit, 0, NULL, 0, \ 1180 CTL_PROC, PROC_CURPROC, PROC_PID_LIMIT, n, \ 1181 PROC_PID_LIMIT_TYPE_HARD, CTL_EOL); \ 1182 } while (0/*CONSTCOND*/) 1183 1184 create_proc_plimit("cputime", PROC_PID_LIMIT_CPU); 1185 create_proc_plimit("filesize", PROC_PID_LIMIT_FSIZE); 1186 create_proc_plimit("datasize", PROC_PID_LIMIT_DATA); 1187 create_proc_plimit("stacksize", PROC_PID_LIMIT_STACK); 1188 create_proc_plimit("coredumpsize", PROC_PID_LIMIT_CORE); 1189 create_proc_plimit("memoryuse", PROC_PID_LIMIT_RSS); 1190 create_proc_plimit("memorylocked", PROC_PID_LIMIT_MEMLOCK); 1191 create_proc_plimit("maxproc", PROC_PID_LIMIT_NPROC); 1192 create_proc_plimit("descriptors", PROC_PID_LIMIT_NOFILE); 1193 create_proc_plimit("sbsize", PROC_PID_LIMIT_SBSIZE); 1194 create_proc_plimit("vmemoryuse", PROC_PID_LIMIT_AS); 1195 create_proc_plimit("maxlwp", PROC_PID_LIMIT_NTHR); 1196 1197 #undef create_proc_plimit 1198 1199 sysctl_createv(&proc_sysctllog, 0, NULL, NULL, 1200 CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE, 1201 CTLTYPE_INT, "stopfork", 1202 SYSCTL_DESCR("Stop process at fork(2)"), 1203 sysctl_proc_stop, 0, NULL, 0, 1204 CTL_PROC, PROC_CURPROC, PROC_PID_STOPFORK, CTL_EOL); 1205 sysctl_createv(&proc_sysctllog, 0, NULL, NULL, 1206 CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE, 1207 CTLTYPE_INT, "stopexec", 1208 SYSCTL_DESCR("Stop process at execve(2)"), 1209 sysctl_proc_stop, 0, NULL, 0, 1210 CTL_PROC, PROC_CURPROC, PROC_PID_STOPEXEC, CTL_EOL); 1211 sysctl_createv(&proc_sysctllog, 0, NULL, NULL, 1212 CTLFLAG_PERMANENT|CTLFLAG_READWRITE|CTLFLAG_ANYWRITE, 1213 CTLTYPE_INT, "stopexit", 1214 SYSCTL_DESCR("Stop process before completing exit"), 1215 sysctl_proc_stop, 0, NULL, 0, 1216 CTL_PROC, PROC_CURPROC, PROC_PID_STOPEXIT, CTL_EOL); 1217 } 1218
Indexes created Sat Sep 20 22:09:52 GMT 2025