1 /* $NetBSD: kern_proc.c,v 1.154 2009/10/04 03:15:08 elad Exp $ */ 2 3 /*- 4 * Copyright (c) 1999, 2006, 2007, 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center, and by Andrew Doran. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1982, 1986, 1989, 1991, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. Neither the name of the University nor the names of its contributors 46 * may be used to endorse or promote products derived from this software 47 * without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 59 * SUCH DAMAGE. 60 * 61 * @(#)kern_proc.c 8.7 (Berkeley) 2/14/95 62 */ 63 64 #include <sys/cdefs.h> 65 __KERNEL_RCSID(0, "$NetBSD: kern_proc.c,v 1.154 2009/10/04 03:15:08 elad Exp $"); 66 67 #include "opt_kstack.h" 68 #include "opt_maxuprc.h" 69 70 #include <sys/param.h> 71 #include <sys/systm.h> 72 #include <sys/kernel.h> 73 #include <sys/proc.h> 74 #include <sys/resourcevar.h> 75 #include <sys/buf.h> 76 #include <sys/acct.h> 77 #include <sys/wait.h> 78 #include <sys/file.h> 79 #include <ufs/ufs/quota.h> 80 #include <sys/uio.h> 81 #include <sys/pool.h> 82 #include <sys/pset.h> 83 #include <sys/mbuf.h> 84 #include <sys/ioctl.h> 85 #include <sys/tty.h> 86 #include <sys/signalvar.h> 87 #include <sys/ras.h> 88 #include <sys/sa.h> 89 #include <sys/savar.h> 90 #include <sys/filedesc.h> 91 #include "sys/syscall_stats.h" 92 #include <sys/kauth.h> 93 #include <sys/sleepq.h> 94 #include <sys/atomic.h> 95 #include <sys/kmem.h> 96 97 #include <uvm/uvm.h> 98 #include <uvm/uvm_extern.h> 99 100 /* 101 * Other process lists 102 */ 103 104 struct proclist allproc; 105 struct proclist zombproc; /* resources have been freed */ 106 107 kmutex_t *proc_lock; 108 109 /* 110 * pid to proc lookup is done by indexing the pid_table array. 111 * Since pid numbers are only allocated when an empty slot 112 * has been found, there is no need to search any lists ever. 113 * (an orphaned pgrp will lock the slot, a session will lock 114 * the pgrp with the same number.) 115 * If the table is too small it is reallocated with twice the 116 * previous size and the entries 'unzipped' into the two halves. 117 * A linked list of free entries is passed through the pt_proc 118 * field of 'free' items - set odd to be an invalid ptr. 119 */ 120 121 struct pid_table { 122 struct proc *pt_proc; 123 struct pgrp *pt_pgrp; 124 }; 125 #if 1 /* strongly typed cast - should be a noop */ 126 static inline uint p2u(struct proc *p) { return (uint)(uintptr_t)p; } 127 #else 128 #define p2u(p) ((uint)p) 129 #endif 130 #define P_VALID(p) (!(p2u(p) & 1)) 131 #define P_NEXT(p) (p2u(p) >> 1) 132 #define P_FREE(pid) ((struct proc *)(uintptr_t)((pid) << 1 | 1)) 133 134 #define INITIAL_PID_TABLE_SIZE (1 << 5) 135 static struct pid_table *pid_table; 136 static uint pid_tbl_mask = INITIAL_PID_TABLE_SIZE - 1; 137 static uint pid_alloc_lim; /* max we allocate before growing table */ 138 static uint pid_alloc_cnt; /* number of allocated pids */ 139 140 /* links through free slots - never empty! */ 141 static uint next_free_pt, last_free_pt; 142 static pid_t pid_max = PID_MAX; /* largest value we allocate */ 143 144 /* Components of the first process -- never freed. */ 145 146 extern struct emul emul_netbsd; /* defined in kern_exec.c */ 147 148 struct session session0 = { 149 .s_count = 1, 150 .s_sid = 0, 151 }; 152 struct pgrp pgrp0 = { 153 .pg_members = LIST_HEAD_INITIALIZER(&pgrp0.pg_members), 154 .pg_session = &session0, 155 }; 156 filedesc_t filedesc0; 157 struct cwdinfo cwdi0 = { 158 .cwdi_cmask = CMASK, /* see cmask below */ 159 .cwdi_refcnt = 1, 160 }; 161 struct plimit limit0; 162 struct pstats pstat0; 163 struct vmspace vmspace0; 164 struct sigacts sigacts0; 165 struct turnstile turnstile0; 166 struct proc proc0 = { 167 .p_lwps = LIST_HEAD_INITIALIZER(&proc0.p_lwps), 168 .p_sigwaiters = LIST_HEAD_INITIALIZER(&proc0.p_sigwaiters), 169 .p_nlwps = 1, 170 .p_nrlwps = 1, 171 .p_nlwpid = 1, /* must match lwp0.l_lid */ 172 .p_pgrp = &pgrp0, 173 .p_comm = "system", 174 /* 175 * Set P_NOCLDWAIT so that kernel threads are reparented to init(8) 176 * when they exit. init(8) can easily wait them out for us. 177 */ 178 .p_flag = PK_SYSTEM | PK_NOCLDWAIT, 179 .p_stat = SACTIVE, 180 .p_nice = NZERO, 181 .p_emul = &emul_netbsd, 182 .p_cwdi = &cwdi0, 183 .p_limit = &limit0, 184 .p_fd = &filedesc0, 185 .p_vmspace = &vmspace0, 186 .p_stats = &pstat0, 187 .p_sigacts = &sigacts0, 188 }; 189 struct lwp lwp0 __aligned(MIN_LWP_ALIGNMENT) = { 190 #ifdef LWP0_CPU_INFO 191 .l_cpu = LWP0_CPU_INFO, 192 #endif 193 .l_proc = &proc0, 194 .l_lid = 1, 195 .l_flag = LW_INMEM | LW_SYSTEM, 196 .l_stat = LSONPROC, 197 .l_ts = &turnstile0, 198 .l_syncobj = &sched_syncobj, 199 .l_refcnt = 1, 200 .l_priority = PRI_USER + NPRI_USER - 1, 201 .l_inheritedprio = -1, 202 .l_class = SCHED_OTHER, 203 .l_psid = PS_NONE, 204 .l_pi_lenders = SLIST_HEAD_INITIALIZER(&lwp0.l_pi_lenders), 205 .l_name = __UNCONST("swapper"), 206 .l_fd = &filedesc0, 207 }; 208 kauth_cred_t cred0; 209 210 extern struct user *proc0paddr; 211 212 int nofile = NOFILE; 213 int maxuprc = MAXUPRC; 214 int cmask = CMASK; 215 216 MALLOC_DEFINE(M_EMULDATA, "emuldata", "Per-process emulation data"); 217 MALLOC_DEFINE(M_SUBPROC, "subproc", "Proc sub-structures"); 218 219 /* 220 * The process list descriptors, used during pid allocation and 221 * by sysctl. No locking on this data structure is needed since 222 * it is completely static. 223 */ 224 const struct proclist_desc proclists[] = { 225 { &allproc }, 226 { &zombproc }, 227 { NULL }, 228 }; 229 230 static struct pgrp * pg_remove(pid_t); 231 static void pg_delete(pid_t); 232 static void orphanpg(struct pgrp *); 233 234 static specificdata_domain_t proc_specificdata_domain; 235 236 static pool_cache_t proc_cache; 237 238 static kauth_listener_t proc_listener; 239 240 static int 241 proc_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, 242 void *arg0, void *arg1, void *arg2, void *arg3) 243 { 244 struct proc *p; 245 int result; 246 247 result = KAUTH_RESULT_DEFER; 248 p = arg0; 249 250 switch (action) { 251 case KAUTH_PROCESS_CANSEE: { 252 enum kauth_process_req req; 253 254 req = (enum kauth_process_req)arg1; 255 256 switch (req) { 257 case KAUTH_REQ_PROCESS_CANSEE_ARGS: 258 case KAUTH_REQ_PROCESS_CANSEE_ENTRY: 259 case KAUTH_REQ_PROCESS_CANSEE_OPENFILES: 260 result = KAUTH_RESULT_ALLOW; 261 262 break; 263 264 case KAUTH_REQ_PROCESS_CANSEE_ENV: 265 if (kauth_cred_getuid(cred) != 266 kauth_cred_getuid(p->p_cred) || 267 kauth_cred_getuid(cred) != 268 kauth_cred_getsvuid(p->p_cred)) 269 break; 270 271 result = KAUTH_RESULT_ALLOW; 272 273 break; 274 275 default: 276 break; 277 } 278 279 break; 280 } 281 282 case KAUTH_PROCESS_FORK: { 283 int lnprocs = (int)(unsigned long)arg2; 284 285 /* 286 * Don't allow a nonprivileged user to use the last few 287 * processes. The variable lnprocs is the current number of 288 * processes, maxproc is the limit. 289 */ 290 if (__predict_false((lnprocs >= maxproc - 5))) 291 break; 292 293 result = KAUTH_RESULT_ALLOW; 294 295 break; 296 } 297 298 case KAUTH_PROCESS_CORENAME: 299 case KAUTH_PROCESS_STOPFLAG: 300 if (proc_uidmatch(cred, p->p_cred) == 0) 301 result = KAUTH_RESULT_ALLOW; 302 303 break; 304 305 default: 306 break; 307 } 308 309 return result; 310 } 311 312 /* 313 * Initialize global process hashing structures. 314 */ 315 void 316 procinit(void) 317 { 318 const struct proclist_desc *pd; 319 u_int i; 320 #define LINK_EMPTY ((PID_MAX + INITIAL_PID_TABLE_SIZE) & ~(INITIAL_PID_TABLE_SIZE - 1)) 321 322 for (pd = proclists; pd->pd_list != NULL; pd++) 323 LIST_INIT(pd->pd_list); 324 325 proc_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE); 326 pid_table = kmem_alloc(INITIAL_PID_TABLE_SIZE 327 * sizeof(struct pid_table), KM_SLEEP); 328 329 /* Set free list running through table... 330 Preset 'use count' above PID_MAX so we allocate pid 1 next. */ 331 for (i = 0; i <= pid_tbl_mask; i++) { 332 pid_table[i].pt_proc = P_FREE(LINK_EMPTY + i + 1); 333 pid_table[i].pt_pgrp = 0; 334 } 335 /* slot 0 is just grabbed */ 336 next_free_pt = 1; 337 /* Need to fix last entry. */ 338 last_free_pt = pid_tbl_mask; 339 pid_table[last_free_pt].pt_proc = P_FREE(LINK_EMPTY); 340 /* point at which we grow table - to avoid reusing pids too often */ 341 pid_alloc_lim = pid_tbl_mask - 1; 342 #undef LINK_EMPTY 343 344 proc_specificdata_domain = specificdata_domain_create(); 345 KASSERT(proc_specificdata_domain != NULL); 346 347 proc_cache = pool_cache_init(sizeof(struct proc), 0, 0, 0, 348 "procpl", NULL, IPL_NONE, NULL, NULL, NULL); 349 350 proc_listener = kauth_listen_scope(KAUTH_SCOPE_PROCESS, 351 proc_listener_cb, NULL); 352 } 353 354 /* 355 * Initialize process 0. 356 */ 357 void 358 proc0_init(void) 359 { 360 struct proc *p; 361 struct pgrp *pg; 362 struct session *sess; 363 struct lwp *l; 364 rlim_t lim; 365 int i; 366 367 p = &proc0; 368 pg = &pgrp0; 369 sess = &session0; 370 l = &lwp0; 371 372 KASSERT(l->l_lid == p->p_nlwpid); 373 374 mutex_init(&p->p_stmutex, MUTEX_DEFAULT, IPL_HIGH); 375 mutex_init(&p->p_auxlock, MUTEX_DEFAULT, IPL_NONE); 376 mutex_init(&l->l_swaplock, MUTEX_DEFAULT, IPL_NONE); 377 p->p_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE); 378 379 rw_init(&p->p_reflock); 380 cv_init(&p->p_waitcv, "wait"); 381 cv_init(&p->p_lwpcv, "lwpwait"); 382 383 LIST_INSERT_HEAD(&p->p_lwps, l, l_sibling); 384 385 pid_table[0].pt_proc = p; 386 LIST_INSERT_HEAD(&allproc, p, p_list); 387 LIST_INSERT_HEAD(&alllwp, l, l_list); 388 389 pid_table[0].pt_pgrp = pg; 390 LIST_INSERT_HEAD(&pg->pg_members, p, p_pglist); 391 392 #ifdef __HAVE_SYSCALL_INTERN 393 (*p->p_emul->e_syscall_intern)(p); 394 #endif 395 396 callout_init(&l->l_timeout_ch, CALLOUT_MPSAFE); 397 callout_setfunc(&l->l_timeout_ch, sleepq_timeout, l); 398 cv_init(&l->l_sigcv, "sigwait"); 399 400 /* Create credentials. */ 401 cred0 = kauth_cred_alloc(); 402 p->p_cred = cred0; 403 kauth_cred_hold(cred0); 404 l->l_cred = cred0; 405 406 /* Create the CWD info. */ 407 rw_init(&cwdi0.cwdi_lock); 408 409 /* Create the limits structures. */ 410 mutex_init(&limit0.pl_lock, MUTEX_DEFAULT, IPL_NONE); 411 for (i = 0; i < __arraycount(limit0.pl_rlimit); i++) 412 limit0.pl_rlimit[i].rlim_cur = 413 limit0.pl_rlimit[i].rlim_max = RLIM_INFINITY; 414 415 limit0.pl_rlimit[RLIMIT_NOFILE].rlim_max = maxfiles; 416 limit0.pl_rlimit[RLIMIT_NOFILE].rlim_cur = 417 maxfiles < nofile ? maxfiles : nofile; 418 419 limit0.pl_rlimit[RLIMIT_NPROC].rlim_max = maxproc; 420 limit0.pl_rlimit[RLIMIT_NPROC].rlim_cur = 421 maxproc < maxuprc ? maxproc : maxuprc; 422 423 lim = ptoa(uvmexp.free); 424 limit0.pl_rlimit[RLIMIT_RSS].rlim_max = lim; 425 limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_max = lim; 426 limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_cur = lim / 3; 427 limit0.pl_corename = defcorename; 428 limit0.pl_refcnt = 1; 429 limit0.pl_sv_limit = NULL; 430 431 /* Configure virtual memory system, set vm rlimits. */ 432 uvm_init_limits(p); 433 434 /* Initialize file descriptor table for proc0. */ 435 fd_init(&filedesc0); 436 437 /* 438 * Initialize proc0's vmspace, which uses the kernel pmap. 439 * All kernel processes (which never have user space mappings) 440 * share proc0's vmspace, and thus, the kernel pmap. 441 */ 442 uvmspace_init(&vmspace0, pmap_kernel(), round_page(VM_MIN_ADDRESS), 443 trunc_page(VM_MAX_ADDRESS)); 444 445 l->l_addr = proc0paddr; /* XXX */ 446 447 /* Initialize signal state for proc0. XXX IPL_SCHED */ 448 mutex_init(&p->p_sigacts->sa_mutex, MUTEX_DEFAULT, IPL_SCHED); 449 siginit(p); 450 451 proc_initspecific(p); 452 lwp_initspecific(l); 453 454 SYSCALL_TIME_LWP_INIT(l); 455 } 456 457 /* 458 * Session reference counting. 459 */ 460 461 void 462 proc_sesshold(struct session *ss) 463 { 464 465 KASSERT(mutex_owned(proc_lock)); 466 ss->s_count++; 467 } 468 469 void 470 proc_sessrele(struct session *ss) 471 { 472 473 KASSERT(mutex_owned(proc_lock)); 474 /* 475 * We keep the pgrp with the same id as the session in order to 476 * stop a process being given the same pid. Since the pgrp holds 477 * a reference to the session, it must be a 'zombie' pgrp by now. 478 */ 479 if (--ss->s_count == 0) { 480 struct pgrp *pg; 481 482 pg = pg_remove(ss->s_sid); 483 mutex_exit(proc_lock); 484 485 kmem_free(pg, sizeof(struct pgrp)); 486 kmem_free(ss, sizeof(struct session)); 487 } else { 488 mutex_exit(proc_lock); 489 } 490 } 491 492 /* 493 * Check that the specified process group is in the session of the 494 * specified process. 495 * Treats -ve ids as process ids. 496 * Used to validate TIOCSPGRP requests. 497 */ 498 int 499 pgid_in_session(struct proc *p, pid_t pg_id) 500 { 501 struct pgrp *pgrp; 502 struct session *session; 503 int error; 504 505 mutex_enter(proc_lock); 506 if (pg_id < 0) { 507 struct proc *p1 = p_find(-pg_id, PFIND_LOCKED | PFIND_UNLOCK_FAIL); 508 if (p1 == NULL) 509 return EINVAL; 510 pgrp = p1->p_pgrp; 511 } else { 512 pgrp = pg_find(pg_id, PFIND_LOCKED | PFIND_UNLOCK_FAIL); 513 if (pgrp == NULL) 514 return EINVAL; 515 } 516 session = pgrp->pg_session; 517 if (session != p->p_pgrp->pg_session) 518 error = EPERM; 519 else 520 error = 0; 521 mutex_exit(proc_lock); 522 523 return error; 524 } 525 526 /* 527 * p_inferior: is p an inferior of q? 528 */ 529 static inline bool 530 p_inferior(struct proc *p, struct proc *q) 531 { 532 533 KASSERT(mutex_owned(proc_lock)); 534 535 for (; p != q; p = p->p_pptr) 536 if (p->p_pid == 0) 537 return false; 538 return true; 539 } 540 541 /* 542 * Locate a process by number 543 */ 544 struct proc * 545 p_find(pid_t pid, uint flags) 546 { 547 struct proc *p; 548 char stat; 549 550 if (!(flags & PFIND_LOCKED)) 551 mutex_enter(proc_lock); 552 553 p = pid_table[pid & pid_tbl_mask].pt_proc; 554 555 /* Only allow live processes to be found by pid. */ 556 /* XXXSMP p_stat */ 557 if (P_VALID(p) && p->p_pid == pid && ((stat = p->p_stat) == SACTIVE || 558 stat == SSTOP || ((flags & PFIND_ZOMBIE) && 559 (stat == SZOMB || stat == SDEAD || stat == SDYING)))) { 560 if (flags & PFIND_UNLOCK_OK) 561 mutex_exit(proc_lock); 562 return p; 563 } 564 if (flags & PFIND_UNLOCK_FAIL) 565 mutex_exit(proc_lock); 566 return NULL; 567 } 568 569 570 /* 571 * Locate a process group by number 572 */ 573 struct pgrp * 574 pg_find(pid_t pgid, uint flags) 575 { 576 struct pgrp *pg; 577 578 if (!(flags & PFIND_LOCKED)) 579 mutex_enter(proc_lock); 580 pg = pid_table[pgid & pid_tbl_mask].pt_pgrp; 581 /* 582 * Can't look up a pgrp that only exists because the session 583 * hasn't died yet (traditional) 584 */ 585 if (pg == NULL || pg->pg_id != pgid || LIST_EMPTY(&pg->pg_members)) { 586 if (flags & PFIND_UNLOCK_FAIL) 587 mutex_exit(proc_lock); 588 return NULL; 589 } 590 591 if (flags & PFIND_UNLOCK_OK) 592 mutex_exit(proc_lock); 593 return pg; 594 } 595 596 static void 597 expand_pid_table(void) 598 { 599 size_t pt_size, tsz; 600 struct pid_table *n_pt, *new_pt; 601 struct proc *proc; 602 struct pgrp *pgrp; 603 pid_t pid; 604 u_int i; 605 606 pt_size = pid_tbl_mask + 1; 607 tsz = pt_size * 2 * sizeof(struct pid_table); 608 new_pt = kmem_alloc(tsz, KM_SLEEP); 609 610 mutex_enter(proc_lock); 611 if (pt_size != pid_tbl_mask + 1) { 612 /* Another process beat us to it... */ 613 mutex_exit(proc_lock); 614 kmem_free(new_pt, tsz); 615 return; 616 } 617 618 /* 619 * Copy entries from old table into new one. 620 * If 'pid' is 'odd' we need to place in the upper half, 621 * even pid's to the lower half. 622 * Free items stay in the low half so we don't have to 623 * fixup the reference to them. 624 * We stuff free items on the front of the freelist 625 * because we can't write to unmodified entries. 626 * Processing the table backwards maintains a semblance 627 * of issueing pid numbers that increase with time. 628 */ 629 i = pt_size - 1; 630 n_pt = new_pt + i; 631 for (; ; i--, n_pt--) { 632 proc = pid_table[i].pt_proc; 633 pgrp = pid_table[i].pt_pgrp; 634 if (!P_VALID(proc)) { 635 /* Up 'use count' so that link is valid */ 636 pid = (P_NEXT(proc) + pt_size) & ~pt_size; 637 proc = P_FREE(pid); 638 if (pgrp) 639 pid = pgrp->pg_id; 640 } else 641 pid = proc->p_pid; 642 643 /* Save entry in appropriate half of table */ 644 n_pt[pid & pt_size].pt_proc = proc; 645 n_pt[pid & pt_size].pt_pgrp = pgrp; 646 647 /* Put other piece on start of free list */ 648 pid = (pid ^ pt_size) & ~pid_tbl_mask; 649 n_pt[pid & pt_size].pt_proc = 650 P_FREE((pid & ~pt_size) | next_free_pt); 651 n_pt[pid & pt_size].pt_pgrp = 0; 652 next_free_pt = i | (pid & pt_size); 653 if (i == 0) 654 break; 655 } 656 657 /* Save old table size and switch tables */ 658 tsz = pt_size * sizeof(struct pid_table); 659 n_pt = pid_table; 660 pid_table = new_pt; 661 pid_tbl_mask = pt_size * 2 - 1; 662 663 /* 664 * pid_max starts as PID_MAX (= 30000), once we have 16384 665 * allocated pids we need it to be larger! 666 */ 667 if (pid_tbl_mask > PID_MAX) { 668 pid_max = pid_tbl_mask * 2 + 1; 669 pid_alloc_lim |= pid_alloc_lim << 1; 670 } else 671 pid_alloc_lim <<= 1; /* doubles number of free slots... */ 672 673 mutex_exit(proc_lock); 674 kmem_free(n_pt, tsz); 675 } 676 677 struct proc * 678 proc_alloc(void) 679 { 680 struct proc *p; 681 int nxt; 682 pid_t pid; 683 struct pid_table *pt; 684 685 p = pool_cache_get(proc_cache, PR_WAITOK); 686 p->p_stat = SIDL; /* protect against others */ 687 688 proc_initspecific(p); 689 /* allocate next free pid */ 690 691 for (;;expand_pid_table()) { 692 if (__predict_false(pid_alloc_cnt >= pid_alloc_lim)) 693 /* ensure pids cycle through 2000+ values */ 694 continue; 695 mutex_enter(proc_lock); 696 pt = &pid_table[next_free_pt]; 697 #ifdef DIAGNOSTIC 698 if (__predict_false(P_VALID(pt->pt_proc) || pt->pt_pgrp)) 699 panic("proc_alloc: slot busy"); 700 #endif 701 nxt = P_NEXT(pt->pt_proc); 702 if (nxt & pid_tbl_mask) 703 break; 704 /* Table full - expand (NB last entry not used....) */ 705 mutex_exit(proc_lock); 706 } 707 708 /* pid is 'saved use count' + 'size' + entry */ 709 pid = (nxt & ~pid_tbl_mask) + pid_tbl_mask + 1 + next_free_pt; 710 if ((uint)pid > (uint)pid_max) 711 pid &= pid_tbl_mask; 712 p->p_pid = pid; 713 next_free_pt = nxt & pid_tbl_mask; 714 715 /* Grab table slot */ 716 pt->pt_proc = p; 717 pid_alloc_cnt++; 718 719 mutex_exit(proc_lock); 720 721 return p; 722 } 723 724 /* 725 * Free a process id - called from proc_free (in kern_exit.c) 726 * 727 * Called with the proc_lock held. 728 */ 729 void 730 proc_free_pid(struct proc *p) 731 { 732 pid_t pid = p->p_pid; 733 struct pid_table *pt; 734 735 KASSERT(mutex_owned(proc_lock)); 736 737 pt = &pid_table[pid & pid_tbl_mask]; 738 #ifdef DIAGNOSTIC 739 if (__predict_false(pt->pt_proc != p)) 740 panic("proc_free: pid_table mismatch, pid %x, proc %p", 741 pid, p); 742 #endif 743 /* save pid use count in slot */ 744 pt->pt_proc = P_FREE(pid & ~pid_tbl_mask); 745 746 if (pt->pt_pgrp == NULL) { 747 /* link last freed entry onto ours */ 748 pid &= pid_tbl_mask; 749 pt = &pid_table[last_free_pt]; 750 pt->pt_proc = P_FREE(P_NEXT(pt->pt_proc) | pid); 751 last_free_pt = pid; 752 pid_alloc_cnt--; 753 } 754 755 atomic_dec_uint(&nprocs); 756 } 757 758 void 759 proc_free_mem(struct proc *p) 760 { 761 762 pool_cache_put(proc_cache, p); 763 } 764 765 /* 766 * proc_enterpgrp: move p to a new or existing process group (and session). 767 * 768 * If we are creating a new pgrp, the pgid should equal 769 * the calling process' pid. 770 * If is only valid to enter a process group that is in the session 771 * of the process. 772 * Also mksess should only be set if we are creating a process group 773 * 774 * Only called from sys_setsid and sys_setpgid. 775 */ 776 int 777 proc_enterpgrp(struct proc *curp, pid_t pid, pid_t pgid, bool mksess) 778 { 779 struct pgrp *new_pgrp, *pgrp; 780 struct session *sess; 781 struct proc *p; 782 int rval; 783 pid_t pg_id = NO_PGID; 784 785 sess = mksess ? kmem_alloc(sizeof(*sess), KM_SLEEP) : NULL; 786 787 /* Allocate data areas we might need before doing any validity checks */ 788 mutex_enter(proc_lock); /* Because pid_table might change */ 789 if (pid_table[pgid & pid_tbl_mask].pt_pgrp == 0) { 790 mutex_exit(proc_lock); 791 new_pgrp = kmem_alloc(sizeof(*new_pgrp), KM_SLEEP); 792 mutex_enter(proc_lock); 793 } else 794 new_pgrp = NULL; 795 rval = EPERM; /* most common error (to save typing) */ 796 797 /* Check pgrp exists or can be created */ 798 pgrp = pid_table[pgid & pid_tbl_mask].pt_pgrp; 799 if (pgrp != NULL && pgrp->pg_id != pgid) 800 goto done; 801 802 /* Can only set another process under restricted circumstances. */ 803 if (pid != curp->p_pid) { 804 /* must exist and be one of our children... */ 805 if ((p = p_find(pid, PFIND_LOCKED)) == NULL || 806 !p_inferior(p, curp)) { 807 rval = ESRCH; 808 goto done; 809 } 810 /* ... in the same session... */ 811 if (sess != NULL || p->p_session != curp->p_session) 812 goto done; 813 /* ... existing pgid must be in same session ... */ 814 if (pgrp != NULL && pgrp->pg_session != p->p_session) 815 goto done; 816 /* ... and not done an exec. */ 817 if (p->p_flag & PK_EXEC) { 818 rval = EACCES; 819 goto done; 820 } 821 } else { 822 /* ... setsid() cannot re-enter a pgrp */ 823 if (mksess && (curp->p_pgid == curp->p_pid || 824 pg_find(curp->p_pid, PFIND_LOCKED))) 825 goto done; 826 p = curp; 827 } 828 829 /* Changing the process group/session of a session 830 leader is definitely off limits. */ 831 if (SESS_LEADER(p)) { 832 if (sess == NULL && p->p_pgrp == pgrp) 833 /* unless it's a definite noop */ 834 rval = 0; 835 goto done; 836 } 837 838 /* Can only create a process group with id of process */ 839 if (pgrp == NULL && pgid != pid) 840 goto done; 841 842 /* Can only create a session if creating pgrp */ 843 if (sess != NULL && pgrp != NULL) 844 goto done; 845 846 /* Check we allocated memory for a pgrp... */ 847 if (pgrp == NULL && new_pgrp == NULL) 848 goto done; 849 850 /* Don't attach to 'zombie' pgrp */ 851 if (pgrp != NULL && LIST_EMPTY(&pgrp->pg_members)) 852 goto done; 853 854 /* Expect to succeed now */ 855 rval = 0; 856 857 if (pgrp == p->p_pgrp) 858 /* nothing to do */ 859 goto done; 860 861 /* Ok all setup, link up required structures */ 862 863 if (pgrp == NULL) { 864 pgrp = new_pgrp; 865 new_pgrp = NULL; 866 if (sess != NULL) { 867 sess->s_sid = p->p_pid; 868 sess->s_leader = p; 869 sess->s_count = 1; 870 sess->s_ttyvp = NULL; 871 sess->s_ttyp = NULL; 872 sess->s_flags = p->p_session->s_flags & ~S_LOGIN_SET; 873 memcpy(sess->s_login, p->p_session->s_login, 874 sizeof(sess->s_login)); 875 p->p_lflag &= ~PL_CONTROLT; 876 } else { 877 sess = p->p_pgrp->pg_session; 878 proc_sesshold(sess); 879 } 880 pgrp->pg_session = sess; 881 sess = NULL; 882 883 pgrp->pg_id = pgid; 884 LIST_INIT(&pgrp->pg_members); 885 #ifdef DIAGNOSTIC 886 if (__predict_false(pid_table[pgid & pid_tbl_mask].pt_pgrp)) 887 panic("enterpgrp: pgrp table slot in use"); 888 if (__predict_false(mksess && p != curp)) 889 panic("enterpgrp: mksession and p != curproc"); 890 #endif 891 pid_table[pgid & pid_tbl_mask].pt_pgrp = pgrp; 892 pgrp->pg_jobc = 0; 893 } 894 895 /* 896 * Adjust eligibility of affected pgrps to participate in job control. 897 * Increment eligibility counts before decrementing, otherwise we 898 * could reach 0 spuriously during the first call. 899 */ 900 fixjobc(p, pgrp, 1); 901 fixjobc(p, p->p_pgrp, 0); 902 903 /* Interlock with ttread(). */ 904 mutex_spin_enter(&tty_lock); 905 906 /* Move process to requested group. */ 907 LIST_REMOVE(p, p_pglist); 908 if (LIST_EMPTY(&p->p_pgrp->pg_members)) 909 /* defer delete until we've dumped the lock */ 910 pg_id = p->p_pgrp->pg_id; 911 p->p_pgrp = pgrp; 912 LIST_INSERT_HEAD(&pgrp->pg_members, p, p_pglist); 913 914 /* Done with the swap; we can release the tty mutex. */ 915 mutex_spin_exit(&tty_lock); 916 917 done: 918 if (pg_id != NO_PGID) { 919 /* Releases proc_lock. */ 920 pg_delete(pg_id); 921 } else { 922 mutex_exit(proc_lock); 923 } 924 if (sess != NULL) 925 kmem_free(sess, sizeof(*sess)); 926 if (new_pgrp != NULL) 927 kmem_free(new_pgrp, sizeof(*new_pgrp)); 928 #ifdef DEBUG_PGRP 929 if (__predict_false(rval)) 930 printf("enterpgrp(%d,%d,%d), curproc %d, rval %d\n", 931 pid, pgid, mksess, curp->p_pid, rval); 932 #endif 933 return rval; 934 } 935 936 /* 937 * proc_leavepgrp: remove a process from its process group. 938 * => must be called with the proc_lock held, which will be released; 939 */ 940 void 941 proc_leavepgrp(struct proc *p) 942 { 943 struct pgrp *pgrp; 944 945 KASSERT(mutex_owned(proc_lock)); 946 947 /* Interlock with ttread() */ 948 mutex_spin_enter(&tty_lock); 949 pgrp = p->p_pgrp; 950 LIST_REMOVE(p, p_pglist); 951 p->p_pgrp = NULL; 952 mutex_spin_exit(&tty_lock); 953 954 if (LIST_EMPTY(&pgrp->pg_members)) { 955 /* Releases proc_lock. */ 956 pg_delete(pgrp->pg_id); 957 } else { 958 mutex_exit(proc_lock); 959 } 960 } 961 962 /* 963 * pg_remove: remove a process group from the table. 964 * => must be called with the proc_lock held; 965 * => returns process group to free; 966 */ 967 static struct pgrp * 968 pg_remove(pid_t pg_id) 969 { 970 struct pgrp *pgrp; 971 struct pid_table *pt; 972 973 KASSERT(mutex_owned(proc_lock)); 974 975 pt = &pid_table[pg_id & pid_tbl_mask]; 976 pgrp = pt->pt_pgrp; 977 978 KASSERT(pgrp != NULL); 979 KASSERT(pgrp->pg_id == pg_id); 980 KASSERT(LIST_EMPTY(&pgrp->pg_members)); 981 982 pt->pt_pgrp = NULL; 983 984 if (!P_VALID(pt->pt_proc)) { 985 /* Orphaned pgrp, put slot onto free list. */ 986 KASSERT((P_NEXT(pt->pt_proc) & pid_tbl_mask) == 0); 987 pg_id &= pid_tbl_mask; 988 pt = &pid_table[last_free_pt]; 989 pt->pt_proc = P_FREE(P_NEXT(pt->pt_proc) | pg_id); 990 last_free_pt = pg_id; 991 pid_alloc_cnt--; 992 } 993 return pgrp; 994 } 995 996 /* 997 * pg_delete: delete and free a process group. 998 * => must be called with the proc_lock held, which will be released. 999 */ 1000 static void 1001 pg_delete(pid_t pg_id) 1002 { 1003 struct pgrp *pg; 1004 struct tty *ttyp; 1005 struct session *ss; 1006 1007 KASSERT(mutex_owned(proc_lock)); 1008 1009 pg = pid_table[pg_id & pid_tbl_mask].pt_pgrp; 1010 if (pg == NULL || pg->pg_id != pg_id || !LIST_EMPTY(&pg->pg_members)) { 1011 mutex_exit(proc_lock); 1012 return; 1013 } 1014 1015 ss = pg->pg_session; 1016 1017 /* Remove reference (if any) from tty to this process group */ 1018 mutex_spin_enter(&tty_lock); 1019 ttyp = ss->s_ttyp; 1020 if (ttyp != NULL && ttyp->t_pgrp == pg) { 1021 ttyp->t_pgrp = NULL; 1022 KASSERT(ttyp->t_session == ss); 1023 } 1024 mutex_spin_exit(&tty_lock); 1025 1026 /* 1027 * The leading process group in a session is freed by proc_sessrele(), 1028 * if last reference. Note: proc_sessrele() releases proc_lock. 1029 */ 1030 pg = (ss->s_sid != pg->pg_id) ? pg_remove(pg_id) : NULL; 1031 proc_sessrele(ss); 1032 1033 if (pg != NULL) { 1034 /* Free it, if was not done by proc_sessrele(). */ 1035 kmem_free(pg, sizeof(struct pgrp)); 1036 } 1037 } 1038 1039 /* 1040 * Adjust pgrp jobc counters when specified process changes process group. 1041 * We count the number of processes in each process group that "qualify" 1042 * the group for terminal job control (those with a parent in a different 1043 * process group of the same session). If that count reaches zero, the 1044 * process group becomes orphaned. Check both the specified process' 1045 * process group and that of its children. 1046 * entering == 0 => p is leaving specified group. 1047 * entering == 1 => p is entering specified group. 1048 * 1049 * Call with proc_lock held. 1050 */ 1051 void 1052 fixjobc(struct proc *p, struct pgrp *pgrp, int entering) 1053 { 1054 struct pgrp *hispgrp; 1055 struct session *mysession = pgrp->pg_session; 1056 struct proc *child; 1057 1058 KASSERT(mutex_owned(proc_lock)); 1059 1060 /* 1061 * Check p's parent to see whether p qualifies its own process 1062 * group; if so, adjust count for p's process group. 1063 */ 1064 hispgrp = p->p_pptr->p_pgrp; 1065 if (hispgrp != pgrp && hispgrp->pg_session == mysession) { 1066 if (entering) { 1067 pgrp->pg_jobc++; 1068 p->p_lflag &= ~PL_ORPHANPG; 1069 } else if (--pgrp->pg_jobc == 0) 1070 orphanpg(pgrp); 1071 } 1072 1073 /* 1074 * Check this process' children to see whether they qualify 1075 * their process groups; if so, adjust counts for children's 1076 * process groups. 1077 */ 1078 LIST_FOREACH(child, &p->p_children, p_sibling) { 1079 hispgrp = child->p_pgrp; 1080 if (hispgrp != pgrp && hispgrp->pg_session == mysession && 1081 !P_ZOMBIE(child)) { 1082 if (entering) { 1083 child->p_lflag &= ~PL_ORPHANPG; 1084 hispgrp->pg_jobc++; 1085 } else if (--hispgrp->pg_jobc == 0) 1086 orphanpg(hispgrp); 1087 } 1088 } 1089 } 1090 1091 /* 1092 * A process group has become orphaned; 1093 * if there are any stopped processes in the group, 1094 * hang-up all process in that group. 1095 * 1096 * Call with proc_lock held. 1097 */ 1098 static void 1099 orphanpg(struct pgrp *pg) 1100 { 1101 struct proc *p; 1102 int doit; 1103 1104 KASSERT(mutex_owned(proc_lock)); 1105 1106 doit = 0; 1107 1108 LIST_FOREACH(p, &pg->pg_members, p_pglist) { 1109 if (p->p_stat == SSTOP) { 1110 p->p_lflag |= PL_ORPHANPG; 1111 psignal(p, SIGHUP); 1112 psignal(p, SIGCONT); 1113 } 1114 } 1115 } 1116 1117 #ifdef DDB 1118 #include <ddb/db_output.h> 1119 void pidtbl_dump(void); 1120 void 1121 pidtbl_dump(void) 1122 { 1123 struct pid_table *pt; 1124 struct proc *p; 1125 struct pgrp *pgrp; 1126 int id; 1127 1128 db_printf("pid table %p size %x, next %x, last %x\n", 1129 pid_table, pid_tbl_mask+1, 1130 next_free_pt, last_free_pt); 1131 for (pt = pid_table, id = 0; id <= pid_tbl_mask; id++, pt++) { 1132 p = pt->pt_proc; 1133 if (!P_VALID(p) && !pt->pt_pgrp) 1134 continue; 1135 db_printf(" id %x: ", id); 1136 if (P_VALID(p)) 1137 db_printf("proc %p id %d (0x%x) %s\n", 1138 p, p->p_pid, p->p_pid, p->p_comm); 1139 else 1140 db_printf("next %x use %x\n", 1141 P_NEXT(p) & pid_tbl_mask, 1142 P_NEXT(p) & ~pid_tbl_mask); 1143 if ((pgrp = pt->pt_pgrp)) { 1144 db_printf("\tsession %p, sid %d, count %d, login %s\n", 1145 pgrp->pg_session, pgrp->pg_session->s_sid, 1146 pgrp->pg_session->s_count, 1147 pgrp->pg_session->s_login); 1148 db_printf("\tpgrp %p, pg_id %d, pg_jobc %d, members %p\n", 1149 pgrp, pgrp->pg_id, pgrp->pg_jobc, 1150 LIST_FIRST(&pgrp->pg_members)); 1151 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) { 1152 db_printf("\t\tpid %d addr %p pgrp %p %s\n", 1153 p->p_pid, p, p->p_pgrp, p->p_comm); 1154 } 1155 } 1156 } 1157 } 1158 #endif /* DDB */ 1159 1160 #ifdef KSTACK_CHECK_MAGIC 1161 #include <sys/user.h> 1162 1163 #define KSTACK_MAGIC 0xdeadbeaf 1164 1165 /* XXX should be per process basis? */ 1166 static int kstackleftmin = KSTACK_SIZE; 1167 static int kstackleftthres = KSTACK_SIZE / 8; 1168 1169 void 1170 kstack_setup_magic(const struct lwp *l) 1171 { 1172 uint32_t *ip; 1173 uint32_t const *end; 1174 1175 KASSERT(l != NULL); 1176 KASSERT(l != &lwp0); 1177 1178 /* 1179 * fill all the stack with magic number 1180 * so that later modification on it can be detected. 1181 */ 1182 ip = (uint32_t *)KSTACK_LOWEST_ADDR(l); 1183 end = (uint32_t *)((char *)KSTACK_LOWEST_ADDR(l) + KSTACK_SIZE); 1184 for (; ip < end; ip++) { 1185 *ip = KSTACK_MAGIC; 1186 } 1187 } 1188 1189 void 1190 kstack_check_magic(const struct lwp *l) 1191 { 1192 uint32_t const *ip, *end; 1193 int stackleft; 1194 1195 KASSERT(l != NULL); 1196 1197 /* don't check proc0 */ /*XXX*/ 1198 if (l == &lwp0) 1199 return; 1200 1201 #ifdef __MACHINE_STACK_GROWS_UP 1202 /* stack grows upwards (eg. hppa) */ 1203 ip = (uint32_t *)((void *)KSTACK_LOWEST_ADDR(l) + KSTACK_SIZE); 1204 end = (uint32_t *)KSTACK_LOWEST_ADDR(l); 1205 for (ip--; ip >= end; ip--) 1206 if (*ip != KSTACK_MAGIC) 1207 break; 1208 1209 stackleft = (void *)KSTACK_LOWEST_ADDR(l) + KSTACK_SIZE - (void *)ip; 1210 #else /* __MACHINE_STACK_GROWS_UP */ 1211 /* stack grows downwards (eg. i386) */ 1212 ip = (uint32_t *)KSTACK_LOWEST_ADDR(l); 1213 end = (uint32_t *)((char *)KSTACK_LOWEST_ADDR(l) + KSTACK_SIZE); 1214 for (; ip < end; ip++) 1215 if (*ip != KSTACK_MAGIC) 1216 break; 1217 1218 stackleft = ((const char *)ip) - (const char *)KSTACK_LOWEST_ADDR(l); 1219 #endif /* __MACHINE_STACK_GROWS_UP */ 1220 1221 if (kstackleftmin > stackleft) { 1222 kstackleftmin = stackleft; 1223 if (stackleft < kstackleftthres) 1224 printf("warning: kernel stack left %d bytes" 1225 "(pid %u:lid %u)\n", stackleft, 1226 (u_int)l->l_proc->p_pid, (u_int)l->l_lid); 1227 } 1228 1229 if (stackleft <= 0) { 1230 panic("magic on the top of kernel stack changed for " 1231 "pid %u, lid %u: maybe kernel stack overflow", 1232 (u_int)l->l_proc->p_pid, (u_int)l->l_lid); 1233 } 1234 } 1235 #endif /* KSTACK_CHECK_MAGIC */ 1236 1237 int 1238 proclist_foreach_call(struct proclist *list, 1239 int (*callback)(struct proc *, void *arg), void *arg) 1240 { 1241 struct proc marker; 1242 struct proc *p; 1243 struct lwp * const l = curlwp; 1244 int ret = 0; 1245 1246 marker.p_flag = PK_MARKER; 1247 uvm_lwp_hold(l); 1248 mutex_enter(proc_lock); 1249 for (p = LIST_FIRST(list); ret == 0 && p != NULL;) { 1250 if (p->p_flag & PK_MARKER) { 1251 p = LIST_NEXT(p, p_list); 1252 continue; 1253 } 1254 LIST_INSERT_AFTER(p, &marker, p_list); 1255 ret = (*callback)(p, arg); 1256 KASSERT(mutex_owned(proc_lock)); 1257 p = LIST_NEXT(&marker, p_list); 1258 LIST_REMOVE(&marker, p_list); 1259 } 1260 mutex_exit(proc_lock); 1261 uvm_lwp_rele(l); 1262 1263 return ret; 1264 } 1265 1266 int 1267 proc_vmspace_getref(struct proc *p, struct vmspace **vm) 1268 { 1269 1270 /* XXXCDC: how should locking work here? */ 1271 1272 /* curproc exception is for coredump. */ 1273 1274 if ((p != curproc && (p->p_sflag & PS_WEXIT) != 0) || 1275 (p->p_vmspace->vm_refcnt < 1)) { /* XXX */ 1276 return EFAULT; 1277 } 1278 1279 uvmspace_addref(p->p_vmspace); 1280 *vm = p->p_vmspace; 1281 1282 return 0; 1283 } 1284 1285 /* 1286 * Acquire a write lock on the process credential. 1287 */ 1288 void 1289 proc_crmod_enter(void) 1290 { 1291 struct lwp *l = curlwp; 1292 struct proc *p = l->l_proc; 1293 struct plimit *lim; 1294 kauth_cred_t oc; 1295 char *cn; 1296 1297 /* Reset what needs to be reset in plimit. */ 1298 if (p->p_limit->pl_corename != defcorename) { 1299 lim_privatise(p, false); 1300 lim = p->p_limit; 1301 mutex_enter(&lim->pl_lock); 1302 cn = lim->pl_corename; 1303 lim->pl_corename = defcorename; 1304 mutex_exit(&lim->pl_lock); 1305 if (cn != defcorename) 1306 free(cn, M_TEMP); 1307 } 1308 1309 mutex_enter(p->p_lock); 1310 1311 /* Ensure the LWP cached credentials are up to date. */ 1312 if ((oc = l->l_cred) != p->p_cred) { 1313 kauth_cred_hold(p->p_cred); 1314 l->l_cred = p->p_cred; 1315 kauth_cred_free(oc); 1316 } 1317 1318 } 1319 1320 /* 1321 * Set in a new process credential, and drop the write lock. The credential 1322 * must have a reference already. Optionally, free a no-longer required 1323 * credential. The scheduler also needs to inspect p_cred, so we also 1324 * briefly acquire the sched state mutex. 1325 */ 1326 void 1327 proc_crmod_leave(kauth_cred_t scred, kauth_cred_t fcred, bool sugid) 1328 { 1329 struct lwp *l = curlwp, *l2; 1330 struct proc *p = l->l_proc; 1331 kauth_cred_t oc; 1332 1333 KASSERT(mutex_owned(p->p_lock)); 1334 1335 /* Is there a new credential to set in? */ 1336 if (scred != NULL) { 1337 p->p_cred = scred; 1338 LIST_FOREACH(l2, &p->p_lwps, l_sibling) { 1339 if (l2 != l) 1340 l2->l_prflag |= LPR_CRMOD; 1341 } 1342 1343 /* Ensure the LWP cached credentials are up to date. */ 1344 if ((oc = l->l_cred) != scred) { 1345 kauth_cred_hold(scred); 1346 l->l_cred = scred; 1347 } 1348 } else 1349 oc = NULL; /* XXXgcc */ 1350 1351 if (sugid) { 1352 /* 1353 * Mark process as having changed credentials, stops 1354 * tracing etc. 1355 */ 1356 p->p_flag |= PK_SUGID; 1357 } 1358 1359 mutex_exit(p->p_lock); 1360 1361 /* If there is a credential to be released, free it now. */ 1362 if (fcred != NULL) { 1363 KASSERT(scred != NULL); 1364 kauth_cred_free(fcred); 1365 if (oc != scred) 1366 kauth_cred_free(oc); 1367 } 1368 } 1369 1370 /* 1371 * proc_specific_key_create -- 1372 * Create a key for subsystem proc-specific data. 1373 */ 1374 int 1375 proc_specific_key_create(specificdata_key_t *keyp, specificdata_dtor_t dtor) 1376 { 1377 1378 return (specificdata_key_create(proc_specificdata_domain, keyp, dtor)); 1379 } 1380 1381 /* 1382 * proc_specific_key_delete -- 1383 * Delete a key for subsystem proc-specific data. 1384 */ 1385 void 1386 proc_specific_key_delete(specificdata_key_t key) 1387 { 1388 1389 specificdata_key_delete(proc_specificdata_domain, key); 1390 } 1391 1392 /* 1393 * proc_initspecific -- 1394 * Initialize a proc's specificdata container. 1395 */ 1396 void 1397 proc_initspecific(struct proc *p) 1398 { 1399 int error; 1400 1401 error = specificdata_init(proc_specificdata_domain, &p->p_specdataref); 1402 KASSERT(error == 0); 1403 } 1404 1405 /* 1406 * proc_finispecific -- 1407 * Finalize a proc's specificdata container. 1408 */ 1409 void 1410 proc_finispecific(struct proc *p) 1411 { 1412 1413 specificdata_fini(proc_specificdata_domain, &p->p_specdataref); 1414 } 1415 1416 /* 1417 * proc_getspecific -- 1418 * Return proc-specific data corresponding to the specified key. 1419 */ 1420 void * 1421 proc_getspecific(struct proc *p, specificdata_key_t key) 1422 { 1423 1424 return (specificdata_getspecific(proc_specificdata_domain, 1425 &p->p_specdataref, key)); 1426 } 1427 1428 /* 1429 * proc_setspecific -- 1430 * Set proc-specific data corresponding to the specified key. 1431 */ 1432 void 1433 proc_setspecific(struct proc *p, specificdata_key_t key, void *data) 1434 { 1435 1436 specificdata_setspecific(proc_specificdata_domain, 1437 &p->p_specdataref, key, data); 1438 } 1439 1440 int 1441 proc_uidmatch(kauth_cred_t cred, kauth_cred_t target) 1442 { 1443 int r = 0; 1444 1445 if (kauth_cred_getuid(cred) != kauth_cred_getuid(target) || 1446 kauth_cred_getuid(cred) != kauth_cred_getsvuid(target)) { 1447 /* 1448 * suid proc of ours or proc not ours 1449 */ 1450 r = EPERM; 1451 } else if (kauth_cred_getgid(target) != kauth_cred_getsvgid(target)) { 1452 /* 1453 * sgid proc has sgid back to us temporarily 1454 */ 1455 r = EPERM; 1456 } else { 1457 /* 1458 * our rgid must be in target's group list (ie, 1459 * sub-processes started by a sgid process) 1460 */ 1461 int ismember = 0; 1462 1463 if (kauth_cred_ismember_gid(cred, 1464 kauth_cred_getgid(target), &ismember) != 0 || 1465 !ismember) 1466 r = EPERM; 1467 } 1468 1469 return (r); 1470 } 1471 1472