1 /* $OpenBSD: kern_resource.c,v 1.30 2005/05/29 03:20:41 deraadt Exp $ */ 2 /* $NetBSD: kern_resource.c,v 1.38 1996/10/23 07:19:38 matthias Exp $ */ 3 4 /*- 5 * Copyright (c) 1982, 1986, 1991, 1993 6 * The Regents of the University of California. All rights reserved. 7 * (c) UNIX System Laboratories, Inc. 8 * All or some portions of this file are derived from material licensed 9 * to the University of California by American Telephone and Telegraph 10 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 11 * the permission of UNIX System Laboratories, Inc. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * @(#)kern_resource.c 8.5 (Berkeley) 1/21/94 38 */ 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/kernel.h> 43 #include <sys/file.h> 44 #include <sys/resourcevar.h> 45 #include <sys/pool.h> 46 #include <sys/proc.h> 47 #include <sys/sched.h> 48 49 #include <sys/mount.h> 50 #include <sys/syscallargs.h> 51 52 #include <uvm/uvm_extern.h> 53 54 /* 55 * Patchable maximum data and stack limits. 56 */ 57 rlim_t maxdmap = MAXDSIZ; 58 rlim_t maxsmap = MAXSSIZ; 59 60 /* 61 * Resource controls and accounting. 62 */ 63 64 int 65 sys_getpriority(curp, v, retval) 66 struct proc *curp; 67 void *v; 68 register_t *retval; 69 { 70 register struct sys_getpriority_args /* { 71 syscallarg(int) which; 72 syscallarg(id_t) who; 73 } */ *uap = v; 74 register struct proc *p; 75 register int low = NZERO + PRIO_MAX + 1; 76 77 switch (SCARG(uap, which)) { 78 79 case PRIO_PROCESS: 80 if (SCARG(uap, who) == 0) 81 p = curp; 82 else 83 p = pfind(SCARG(uap, who)); 84 if (p == 0) 85 break; 86 low = p->p_nice; 87 break; 88 89 case PRIO_PGRP: { 90 register struct pgrp *pg; 91 92 if (SCARG(uap, who) == 0) 93 pg = curp->p_pgrp; 94 else if ((pg = pgfind(SCARG(uap, who))) == NULL) 95 break; 96 LIST_FOREACH(p, &pg->pg_members, p_pglist) { 97 if (p->p_nice < low) 98 low = p->p_nice; 99 } 100 break; 101 } 102 103 case PRIO_USER: 104 if (SCARG(uap, who) == 0) 105 SCARG(uap, who) = curp->p_ucred->cr_uid; 106 for (p = LIST_FIRST(&allproc); p; p = LIST_NEXT(p, p_list)) 107 if (p->p_ucred->cr_uid == SCARG(uap, who) && 108 p->p_nice < low) 109 low = p->p_nice; 110 break; 111 112 default: 113 return (EINVAL); 114 } 115 if (low == NZERO + PRIO_MAX + 1) 116 return (ESRCH); 117 *retval = low - NZERO; 118 return (0); 119 } 120 121 /* ARGSUSED */ 122 int 123 sys_setpriority(curp, v, retval) 124 struct proc *curp; 125 void *v; 126 register_t *retval; 127 { 128 register struct sys_setpriority_args /* { 129 syscallarg(int) which; 130 syscallarg(id_t) who; 131 syscallarg(int) prio; 132 } */ *uap = v; 133 register struct proc *p; 134 int found = 0, error = 0; 135 136 switch (SCARG(uap, which)) { 137 138 case PRIO_PROCESS: 139 if (SCARG(uap, who) == 0) 140 p = curp; 141 else 142 p = pfind(SCARG(uap, who)); 143 if (p == 0) 144 break; 145 error = donice(curp, p, SCARG(uap, prio)); 146 found++; 147 break; 148 149 case PRIO_PGRP: { 150 register struct pgrp *pg; 151 152 if (SCARG(uap, who) == 0) 153 pg = curp->p_pgrp; 154 else if ((pg = pgfind(SCARG(uap, who))) == NULL) 155 break; 156 LIST_FOREACH(p, &pg->pg_members, p_pglist) { 157 error = donice(curp, p, SCARG(uap, prio)); 158 found++; 159 } 160 break; 161 } 162 163 case PRIO_USER: 164 if (SCARG(uap, who) == 0) 165 SCARG(uap, who) = curp->p_ucred->cr_uid; 166 for (p = LIST_FIRST(&allproc); p; p = LIST_NEXT(p, p_list)) 167 if (p->p_ucred->cr_uid == SCARG(uap, who)) { 168 error = donice(curp, p, SCARG(uap, prio)); 169 found++; 170 } 171 break; 172 173 default: 174 return (EINVAL); 175 } 176 if (found == 0) 177 return (ESRCH); 178 return (error); 179 } 180 181 int 182 donice(curp, chgp, n) 183 register struct proc *curp, *chgp; 184 register int n; 185 { 186 register struct pcred *pcred = curp->p_cred; 187 int s; 188 189 if (pcred->pc_ucred->cr_uid && pcred->p_ruid && 190 pcred->pc_ucred->cr_uid != chgp->p_ucred->cr_uid && 191 pcred->p_ruid != chgp->p_ucred->cr_uid) 192 return (EPERM); 193 if (n > PRIO_MAX) 194 n = PRIO_MAX; 195 if (n < PRIO_MIN) 196 n = PRIO_MIN; 197 n += NZERO; 198 if (n < chgp->p_nice && suser(curp, 0)) 199 return (EACCES); 200 chgp->p_nice = n; 201 SCHED_LOCK(s); 202 (void)resetpriority(chgp); 203 SCHED_UNLOCK(s); 204 return (0); 205 } 206 207 /* ARGSUSED */ 208 int 209 sys_setrlimit(p, v, retval) 210 struct proc *p; 211 void *v; 212 register_t *retval; 213 { 214 register struct sys_setrlimit_args /* { 215 syscallarg(int) which; 216 syscallarg(const struct rlimit *) rlp; 217 } */ *uap = v; 218 struct rlimit alim; 219 int error; 220 221 error = copyin((caddr_t)SCARG(uap, rlp), (caddr_t)&alim, 222 sizeof (struct rlimit)); 223 if (error) 224 return (error); 225 return (dosetrlimit(p, SCARG(uap, which), &alim)); 226 } 227 228 int 229 dosetrlimit(p, which, limp) 230 struct proc *p; 231 u_int which; 232 struct rlimit *limp; 233 { 234 struct rlimit *alimp; 235 rlim_t maxlim; 236 int error; 237 238 if (which >= RLIM_NLIMITS) 239 return (EINVAL); 240 241 alimp = &p->p_rlimit[which]; 242 if (limp->rlim_cur > alimp->rlim_max || 243 limp->rlim_max > alimp->rlim_max) 244 if ((error = suser(p, 0)) != 0) 245 return (error); 246 if (p->p_limit->p_refcnt > 1 && 247 (p->p_limit->p_lflags & PL_SHAREMOD) == 0) { 248 p->p_limit->p_refcnt--; 249 p->p_limit = limcopy(p->p_limit); 250 alimp = &p->p_rlimit[which]; 251 } 252 253 switch (which) { 254 case RLIMIT_DATA: 255 maxlim = maxdmap; 256 break; 257 case RLIMIT_STACK: 258 maxlim = maxsmap; 259 break; 260 case RLIMIT_NOFILE: 261 maxlim = maxfiles; 262 break; 263 case RLIMIT_NPROC: 264 maxlim = maxproc; 265 break; 266 default: 267 maxlim = RLIM_INFINITY; 268 break; 269 } 270 271 if (limp->rlim_max > maxlim) 272 limp->rlim_max = maxlim; 273 if (limp->rlim_cur > limp->rlim_max) 274 limp->rlim_cur = limp->rlim_max; 275 276 if (which == RLIMIT_STACK) { 277 /* 278 * Stack is allocated to the max at exec time with only 279 * "rlim_cur" bytes accessible. If stack limit is going 280 * up make more accessible, if going down make inaccessible. 281 */ 282 if (limp->rlim_cur != alimp->rlim_cur) { 283 vaddr_t addr; 284 vsize_t size; 285 vm_prot_t prot; 286 287 if (limp->rlim_cur > alimp->rlim_cur) { 288 prot = VM_PROT_READ|VM_PROT_WRITE; 289 size = limp->rlim_cur - alimp->rlim_cur; 290 #ifdef MACHINE_STACK_GROWS_UP 291 addr = USRSTACK + alimp->rlim_cur; 292 #else 293 addr = USRSTACK - limp->rlim_cur; 294 #endif 295 } else { 296 prot = VM_PROT_NONE; 297 size = alimp->rlim_cur - limp->rlim_cur; 298 #ifdef MACHINE_STACK_GROWS_UP 299 addr = USRSTACK + limp->rlim_cur; 300 #else 301 addr = USRSTACK - alimp->rlim_cur; 302 #endif 303 } 304 addr = trunc_page(addr); 305 size = round_page(size); 306 (void) uvm_map_protect(&p->p_vmspace->vm_map, 307 addr, addr+size, prot, FALSE); 308 } 309 } 310 311 *alimp = *limp; 312 return (0); 313 } 314 315 /* ARGSUSED */ 316 int 317 sys_getrlimit(p, v, retval) 318 struct proc *p; 319 void *v; 320 register_t *retval; 321 { 322 register struct sys_getrlimit_args /* { 323 syscallarg(int) which; 324 syscallarg(struct rlimit *) rlp; 325 } */ *uap = v; 326 327 if (SCARG(uap, which) < 0 || SCARG(uap, which) >= RLIM_NLIMITS) 328 return (EINVAL); 329 return (copyout((caddr_t)&p->p_rlimit[SCARG(uap, which)], 330 (caddr_t)SCARG(uap, rlp), sizeof (struct rlimit))); 331 } 332 333 /* 334 * Transform the running time and tick information in proc p into user, 335 * system, and interrupt time usage. 336 */ 337 void 338 calcru(p, up, sp, ip) 339 struct proc *p; 340 struct timeval *up; 341 struct timeval *sp; 342 struct timeval *ip; 343 { 344 u_quad_t st, ut, it; 345 int freq; 346 int s; 347 348 s = splstatclock(); 349 st = p->p_sticks; 350 ut = p->p_uticks; 351 it = p->p_iticks; 352 splx(s); 353 354 if (st + ut + it == 0) { 355 timerclear(up); 356 timerclear(sp); 357 if (ip != NULL) 358 timerclear(ip); 359 return; 360 } 361 362 freq = stathz ? stathz : hz; 363 364 st = st * 1000000 / freq; 365 sp->tv_sec = st / 1000000; 366 sp->tv_usec = st % 1000000; 367 ut = ut * 1000000 / freq; 368 up->tv_sec = ut / 1000000; 369 up->tv_usec = ut % 1000000; 370 if (ip != NULL) { 371 it = it * 1000000 / freq; 372 ip->tv_sec = it / 1000000; 373 ip->tv_usec = it % 1000000; 374 } 375 } 376 377 /* ARGSUSED */ 378 int 379 sys_getrusage(p, v, retval) 380 register struct proc *p; 381 void *v; 382 register_t *retval; 383 { 384 register struct sys_getrusage_args /* { 385 syscallarg(int) who; 386 syscallarg(struct rusage *) rusage; 387 } */ *uap = v; 388 register struct rusage *rup; 389 390 switch (SCARG(uap, who)) { 391 392 case RUSAGE_SELF: 393 rup = &p->p_stats->p_ru; 394 calcru(p, &rup->ru_utime, &rup->ru_stime, NULL); 395 break; 396 397 case RUSAGE_CHILDREN: 398 rup = &p->p_stats->p_cru; 399 break; 400 401 default: 402 return (EINVAL); 403 } 404 return (copyout((caddr_t)rup, (caddr_t)SCARG(uap, rusage), 405 sizeof (struct rusage))); 406 } 407 408 void 409 ruadd(ru, ru2) 410 register struct rusage *ru, *ru2; 411 { 412 register long *ip, *ip2; 413 register int i; 414 415 timeradd(&ru->ru_utime, &ru2->ru_utime, &ru->ru_utime); 416 timeradd(&ru->ru_stime, &ru2->ru_stime, &ru->ru_stime); 417 if (ru->ru_maxrss < ru2->ru_maxrss) 418 ru->ru_maxrss = ru2->ru_maxrss; 419 ip = &ru->ru_first; ip2 = &ru2->ru_first; 420 for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--) 421 *ip++ += *ip2++; 422 } 423 424 struct pool plimit_pool; 425 426 /* 427 * Make a copy of the plimit structure. 428 * We share these structures copy-on-write after fork, 429 * and copy when a limit is changed. 430 */ 431 struct plimit * 432 limcopy(struct plimit *lim) 433 { 434 struct plimit *newlim; 435 static int initialized; 436 437 if (!initialized) { 438 pool_init(&plimit_pool, sizeof(struct plimit), 0, 0, 0, 439 "plimitpl", &pool_allocator_nointr); 440 initialized = 1; 441 } 442 443 newlim = pool_get(&plimit_pool, PR_WAITOK); 444 bcopy(lim->pl_rlimit, newlim->pl_rlimit, 445 sizeof(struct rlimit) * RLIM_NLIMITS); 446 newlim->p_lflags = 0; 447 newlim->p_refcnt = 1; 448 return (newlim); 449 } 450 451 void 452 limfree(struct plimit *lim) 453 { 454 if (--lim->p_refcnt > 0) 455 return; 456 pool_put(&plimit_pool, lim); 457 } 458