1 /* $OpenBSD: kern_proc.c,v 1.94 2023/01/02 23:09:48 guenther Exp $ */ 2 /* $NetBSD: kern_proc.c,v 1.14 1996/02/09 18:59:41 christos Exp $ */ 3 4 /* 5 * Copyright (c) 1982, 1986, 1989, 1991, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#)kern_proc.c 8.4 (Berkeley) 1/4/94 33 */ 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/proc.h> 38 #include <sys/wait.h> 39 #include <sys/rwlock.h> 40 #include <sys/malloc.h> 41 #include <sys/tty.h> 42 #include <sys/signalvar.h> 43 #include <sys/pool.h> 44 #include <sys/vnode.h> 45 46 /* 47 * Locks used to protect struct members in this file: 48 * I immutable after creation 49 * U uidinfolk 50 */ 51 52 struct rwlock uidinfolk; 53 #define UIHASH(uid) (&uihashtbl[(uid) & uihash]) 54 LIST_HEAD(uihashhead, uidinfo) *uihashtbl; /* [U] */ 55 u_long uihash; /* [I] size of hash table - 1 */ 56 57 /* 58 * Other process lists 59 */ 60 struct tidhashhead *tidhashtbl; 61 u_long tidhash; 62 struct pidhashhead *pidhashtbl; 63 u_long pidhash; 64 struct pgrphashhead *pgrphashtbl; 65 u_long pgrphash; 66 struct processlist allprocess; 67 struct processlist zombprocess; 68 struct proclist allproc; 69 70 struct pool proc_pool; 71 struct pool process_pool; 72 struct pool rusage_pool; 73 struct pool ucred_pool; 74 struct pool pgrp_pool; 75 struct pool session_pool; 76 77 void pgdelete(struct pgrp *); 78 void fixjobc(struct process *, struct pgrp *, int); 79 80 static void orphanpg(struct pgrp *); 81 #ifdef DEBUG 82 void pgrpdump(void); 83 #endif 84 85 /* 86 * Initialize global process hashing structures. 87 */ 88 void 89 procinit(void) 90 { 91 LIST_INIT(&allprocess); 92 LIST_INIT(&zombprocess); 93 LIST_INIT(&allproc); 94 95 rw_init(&uidinfolk, "uidinfo"); 96 97 tidhashtbl = hashinit(maxthread / 4, M_PROC, M_NOWAIT, &tidhash); 98 pidhashtbl = hashinit(maxprocess / 4, M_PROC, M_NOWAIT, &pidhash); 99 pgrphashtbl = hashinit(maxprocess / 4, M_PROC, M_NOWAIT, &pgrphash); 100 uihashtbl = hashinit(maxprocess / 16, M_PROC, M_NOWAIT, &uihash); 101 if (!tidhashtbl || !pidhashtbl || !pgrphashtbl || !uihashtbl) 102 panic("procinit: malloc"); 103 104 pool_init(&proc_pool, sizeof(struct proc), 0, IPL_NONE, 105 PR_WAITOK, "procpl", NULL); 106 pool_init(&process_pool, sizeof(struct process), 0, IPL_NONE, 107 PR_WAITOK, "processpl", NULL); 108 pool_init(&rusage_pool, sizeof(struct rusage), 0, IPL_NONE, 109 PR_WAITOK, "zombiepl", NULL); 110 pool_init(&ucred_pool, sizeof(struct ucred), 0, IPL_MPFLOOR, 111 0, "ucredpl", NULL); 112 pool_init(&pgrp_pool, sizeof(struct pgrp), 0, IPL_NONE, 113 PR_WAITOK, "pgrppl", NULL); 114 pool_init(&session_pool, sizeof(struct session), 0, IPL_NONE, 115 PR_WAITOK, "sessionpl", NULL); 116 } 117 118 /* 119 * This returns with `uidinfolk' held: caller must call uid_release() 120 * after making whatever change they needed. 121 */ 122 struct uidinfo * 123 uid_find(uid_t uid) 124 { 125 struct uidinfo *uip, *nuip; 126 struct uihashhead *uipp; 127 128 uipp = UIHASH(uid); 129 rw_enter_write(&uidinfolk); 130 LIST_FOREACH(uip, uipp, ui_hash) 131 if (uip->ui_uid == uid) 132 break; 133 if (uip) 134 return (uip); 135 rw_exit_write(&uidinfolk); 136 nuip = malloc(sizeof(*nuip), M_PROC, M_WAITOK|M_ZERO); 137 rw_enter_write(&uidinfolk); 138 LIST_FOREACH(uip, uipp, ui_hash) 139 if (uip->ui_uid == uid) 140 break; 141 if (uip) { 142 free(nuip, M_PROC, sizeof(*nuip)); 143 return (uip); 144 } 145 nuip->ui_uid = uid; 146 LIST_INSERT_HEAD(uipp, nuip, ui_hash); 147 148 return (nuip); 149 } 150 151 void 152 uid_release(struct uidinfo *uip) 153 { 154 rw_exit_write(&uidinfolk); 155 } 156 157 /* 158 * Change the count associated with number of threads 159 * a given user is using. 160 */ 161 int 162 chgproccnt(uid_t uid, int diff) 163 { 164 struct uidinfo *uip; 165 long count; 166 167 uip = uid_find(uid); 168 count = (uip->ui_proccnt += diff); 169 uid_release(uip); 170 if (count < 0) 171 panic("chgproccnt: procs < 0"); 172 return count; 173 } 174 175 /* 176 * Is pr an inferior of parent? 177 */ 178 int 179 inferior(struct process *pr, struct process *parent) 180 { 181 182 for (; pr != parent; pr = pr->ps_pptr) 183 if (pr->ps_pid == 0 || pr->ps_pid == 1) 184 return (0); 185 return (1); 186 } 187 188 /* 189 * Locate a proc (thread) by number 190 */ 191 struct proc * 192 tfind(pid_t tid) 193 { 194 struct proc *p; 195 196 LIST_FOREACH(p, TIDHASH(tid), p_hash) 197 if (p->p_tid == tid) 198 return (p); 199 return (NULL); 200 } 201 202 /* 203 * Locate a thread by userspace id, from a given process. 204 */ 205 struct proc * 206 tfind_user(pid_t tid, struct process *pr) 207 { 208 struct proc *p; 209 210 if (tid < THREAD_PID_OFFSET) 211 return NULL; 212 p = tfind(tid - THREAD_PID_OFFSET); 213 214 /* verify we found a thread in the correct process */ 215 if (p != NULL && p->p_p != pr) 216 p = NULL; 217 return p; 218 } 219 220 /* 221 * Locate a process by number 222 */ 223 struct process * 224 prfind(pid_t pid) 225 { 226 struct process *pr; 227 228 LIST_FOREACH(pr, PIDHASH(pid), ps_hash) 229 if (pr->ps_pid == pid) 230 return (pr); 231 return (NULL); 232 } 233 234 /* 235 * Locate a process group by number 236 */ 237 struct pgrp * 238 pgfind(pid_t pgid) 239 { 240 struct pgrp *pgrp; 241 242 LIST_FOREACH(pgrp, PGRPHASH(pgid), pg_hash) 243 if (pgrp->pg_id == pgid) 244 return (pgrp); 245 return (NULL); 246 } 247 248 /* 249 * Locate a zombie process 250 */ 251 struct process * 252 zombiefind(pid_t pid) 253 { 254 struct process *pr; 255 256 LIST_FOREACH(pr, &zombprocess, ps_list) 257 if (pr->ps_pid == pid) 258 return (pr); 259 return (NULL); 260 } 261 262 /* 263 * Move process to a new process group. If a session is provided 264 * then it's a new session to contain this process group; otherwise 265 * the process is staying within its existing session. 266 */ 267 void 268 enternewpgrp(struct process *pr, struct pgrp *pgrp, struct session *newsess) 269 { 270 #ifdef DIAGNOSTIC 271 if (SESS_LEADER(pr)) 272 panic("%s: session leader attempted setpgrp", __func__); 273 #endif 274 275 if (newsess != NULL) { 276 /* 277 * New session. Initialize it completely 278 */ 279 timeout_set(&newsess->s_verauthto, zapverauth, newsess); 280 newsess->s_leader = pr; 281 newsess->s_count = 1; 282 newsess->s_ttyvp = NULL; 283 newsess->s_ttyp = NULL; 284 memcpy(newsess->s_login, pr->ps_session->s_login, 285 sizeof(newsess->s_login)); 286 atomic_clearbits_int(&pr->ps_flags, PS_CONTROLT); 287 pgrp->pg_session = newsess; 288 #ifdef DIAGNOSTIC 289 if (pr != curproc->p_p) 290 panic("%s: mksession but not curproc", __func__); 291 #endif 292 } else { 293 pgrp->pg_session = pr->ps_session; 294 pgrp->pg_session->s_count++; 295 } 296 pgrp->pg_id = pr->ps_pid; 297 LIST_INIT(&pgrp->pg_members); 298 LIST_INIT(&pgrp->pg_sigiolst); 299 LIST_INSERT_HEAD(PGRPHASH(pr->ps_pid), pgrp, pg_hash); 300 pgrp->pg_jobc = 0; 301 302 enterthispgrp(pr, pgrp); 303 } 304 305 /* 306 * move process to an existing process group 307 */ 308 void 309 enterthispgrp(struct process *pr, struct pgrp *pgrp) 310 { 311 struct pgrp *savepgrp = pr->ps_pgrp; 312 313 /* 314 * Adjust eligibility of affected pgrps to participate in job control. 315 * Increment eligibility counts before decrementing, otherwise we 316 * could reach 0 spuriously during the first call. 317 */ 318 fixjobc(pr, pgrp, 1); 319 fixjobc(pr, savepgrp, 0); 320 321 LIST_REMOVE(pr, ps_pglist); 322 pr->ps_pgrp = pgrp; 323 LIST_INSERT_HEAD(&pgrp->pg_members, pr, ps_pglist); 324 if (LIST_EMPTY(&savepgrp->pg_members)) 325 pgdelete(savepgrp); 326 } 327 328 /* 329 * remove process from process group 330 */ 331 void 332 leavepgrp(struct process *pr) 333 { 334 335 if (pr->ps_session->s_verauthppid == pr->ps_pid) 336 zapverauth(pr->ps_session); 337 LIST_REMOVE(pr, ps_pglist); 338 if (LIST_EMPTY(&pr->ps_pgrp->pg_members)) 339 pgdelete(pr->ps_pgrp); 340 pr->ps_pgrp = NULL; 341 } 342 343 /* 344 * delete a process group 345 */ 346 void 347 pgdelete(struct pgrp *pgrp) 348 { 349 sigio_freelist(&pgrp->pg_sigiolst); 350 351 if (pgrp->pg_session->s_ttyp != NULL && 352 pgrp->pg_session->s_ttyp->t_pgrp == pgrp) 353 pgrp->pg_session->s_ttyp->t_pgrp = NULL; 354 LIST_REMOVE(pgrp, pg_hash); 355 SESSRELE(pgrp->pg_session); 356 pool_put(&pgrp_pool, pgrp); 357 } 358 359 void 360 zapverauth(void *v) 361 { 362 struct session *sess = v; 363 sess->s_verauthuid = 0; 364 sess->s_verauthppid = 0; 365 } 366 367 /* 368 * Adjust pgrp jobc counters when specified process changes process group. 369 * We count the number of processes in each process group that "qualify" 370 * the group for terminal job control (those with a parent in a different 371 * process group of the same session). If that count reaches zero, the 372 * process group becomes orphaned. Check both the specified process' 373 * process group and that of its children. 374 * entering == 0 => pr is leaving specified group. 375 * entering == 1 => pr is entering specified group. 376 * XXX need proctree lock 377 */ 378 void 379 fixjobc(struct process *pr, struct pgrp *pgrp, int entering) 380 { 381 struct pgrp *hispgrp; 382 struct session *mysession = pgrp->pg_session; 383 384 /* 385 * Check pr's parent to see whether pr qualifies its own process 386 * group; if so, adjust count for pr's process group. 387 */ 388 if ((hispgrp = pr->ps_pptr->ps_pgrp) != pgrp && 389 hispgrp->pg_session == mysession) { 390 if (entering) 391 pgrp->pg_jobc++; 392 else if (--pgrp->pg_jobc == 0) 393 orphanpg(pgrp); 394 } 395 396 /* 397 * Check this process' children to see whether they qualify 398 * their process groups; if so, adjust counts for children's 399 * process groups. 400 */ 401 LIST_FOREACH(pr, &pr->ps_children, ps_sibling) 402 if ((hispgrp = pr->ps_pgrp) != pgrp && 403 hispgrp->pg_session == mysession && 404 (pr->ps_flags & PS_ZOMBIE) == 0) { 405 if (entering) 406 hispgrp->pg_jobc++; 407 else if (--hispgrp->pg_jobc == 0) 408 orphanpg(hispgrp); 409 } 410 } 411 412 void 413 killjobc(struct process *pr) 414 { 415 if (SESS_LEADER(pr)) { 416 struct session *sp = pr->ps_session; 417 418 if (sp->s_ttyvp) { 419 struct vnode *ovp; 420 421 /* 422 * Controlling process. 423 * Signal foreground pgrp, 424 * drain controlling terminal 425 * and revoke access to controlling terminal. 426 */ 427 if (sp->s_ttyp->t_session == sp) { 428 if (sp->s_ttyp->t_pgrp) 429 pgsignal(sp->s_ttyp->t_pgrp, SIGHUP, 1); 430 ttywait(sp->s_ttyp); 431 /* 432 * The tty could have been revoked 433 * if we blocked. 434 */ 435 if (sp->s_ttyvp) 436 VOP_REVOKE(sp->s_ttyvp, REVOKEALL); 437 } 438 ovp = sp->s_ttyvp; 439 sp->s_ttyvp = NULL; 440 if (ovp) 441 vrele(ovp); 442 /* 443 * s_ttyp is not zero'd; we use this to 444 * indicate that the session once had a 445 * controlling terminal. (for logging and 446 * informational purposes) 447 */ 448 } 449 sp->s_leader = NULL; 450 } 451 fixjobc(pr, pr->ps_pgrp, 0); 452 } 453 454 /* 455 * A process group has become orphaned; 456 * if there are any stopped processes in the group, 457 * hang-up all process in that group. 458 */ 459 static void 460 orphanpg(struct pgrp *pg) 461 { 462 struct process *pr; 463 464 LIST_FOREACH(pr, &pg->pg_members, ps_pglist) { 465 if (pr->ps_mainproc->p_stat == SSTOP) { 466 LIST_FOREACH(pr, &pg->pg_members, ps_pglist) { 467 prsignal(pr, SIGHUP); 468 prsignal(pr, SIGCONT); 469 } 470 return; 471 } 472 } 473 } 474 475 #ifdef DDB 476 void 477 proc_printit(struct proc *p, const char *modif, 478 int (*pr)(const char *, ...) __attribute__((__format__(__kprintf__,1,2)))) 479 { 480 static const char *const pstat[] = { 481 "idle", "run", "sleep", "stop", "zombie", "dead", "onproc" 482 }; 483 char pstbuf[5]; 484 const char *pst = pstbuf; 485 486 487 if (p->p_stat < 1 || p->p_stat > sizeof(pstat) / sizeof(pstat[0])) 488 snprintf(pstbuf, sizeof(pstbuf), "%d", p->p_stat); 489 else 490 pst = pstat[(int)p->p_stat - 1]; 491 492 (*pr)("PROC (%s) pid=%d stat=%s\n", p->p_p->ps_comm, p->p_tid, pst); 493 (*pr)(" flags process=%b proc=%b\n", 494 p->p_p->ps_flags, PS_BITS, p->p_flag, P_BITS); 495 (*pr)(" pri=%u, usrpri=%u, nice=%d\n", 496 p->p_runpri, p->p_usrpri, p->p_p->ps_nice); 497 (*pr)(" forw=%p, list=%p,%p\n", 498 TAILQ_NEXT(p, p_runq), p->p_list.le_next, p->p_list.le_prev); 499 (*pr)(" process=%p user=%p, vmspace=%p\n", 500 p->p_p, p->p_addr, p->p_vmspace); 501 (*pr)(" estcpu=%u, cpticks=%d, pctcpu=%u.%u\n", 502 p->p_estcpu, p->p_cpticks, p->p_pctcpu / 100, p->p_pctcpu % 100); 503 (*pr)(" user=%u, sys=%u, intr=%u\n", 504 p->p_uticks, p->p_sticks, p->p_iticks); 505 } 506 #include <machine/db_machdep.h> 507 508 #include <ddb/db_output.h> 509 510 void 511 db_kill_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif) 512 { 513 struct process *pr; 514 struct proc *p; 515 516 pr = prfind(addr); 517 if (pr == NULL) { 518 db_printf("%ld: No such process", addr); 519 return; 520 } 521 522 p = TAILQ_FIRST(&pr->ps_threads); 523 524 /* Send uncatchable SIGABRT for coredump */ 525 sigabort(p); 526 } 527 528 void 529 db_show_all_procs(db_expr_t addr, int haddr, db_expr_t count, char *modif) 530 { 531 char *mode; 532 int skipzomb = 0; 533 int has_kernel_lock = 0; 534 struct proc *p; 535 struct process *pr, *ppr; 536 537 if (modif[0] == 0) 538 modif[0] = 'n'; /* default == normal mode */ 539 540 mode = "mawno"; 541 while (*mode && *mode != modif[0]) 542 mode++; 543 if (*mode == 0 || *mode == 'm') { 544 db_printf("usage: show all procs [/a] [/n] [/w]\n"); 545 db_printf("\t/a == show process address info\n"); 546 db_printf("\t/n == show normal process info [default]\n"); 547 db_printf("\t/w == show process pgrp/wait info\n"); 548 db_printf("\t/o == show normal info for non-idle SONPROC\n"); 549 return; 550 } 551 552 pr = LIST_FIRST(&allprocess); 553 554 switch (*mode) { 555 556 case 'a': 557 db_printf(" TID %-9s %18s %18s %18s\n", 558 "COMMAND", "STRUCT PROC *", "UAREA *", "VMSPACE/VM_MAP"); 559 break; 560 case 'n': 561 db_printf(" PID %6s %5s %5s S %10s %-12s %-15s\n", 562 "TID", "PPID", "UID", "FLAGS", "WAIT", "COMMAND"); 563 break; 564 case 'w': 565 db_printf(" TID %-15s %-5s %18s %s\n", 566 "COMMAND", "PGRP", "WAIT-CHANNEL", "WAIT-MSG"); 567 break; 568 case 'o': 569 skipzomb = 1; 570 db_printf(" TID %5s %5s %10s %10s %3s %-30s\n", 571 "PID", "UID", "PRFLAGS", "PFLAGS", "CPU", "COMMAND"); 572 break; 573 } 574 575 while (pr != NULL) { 576 ppr = pr->ps_pptr; 577 578 TAILQ_FOREACH(p, &pr->ps_threads, p_thr_link) { 579 #ifdef MULTIPROCESSOR 580 if (__mp_lock_held(&kernel_lock, p->p_cpu)) 581 has_kernel_lock = 1; 582 else 583 has_kernel_lock = 0; 584 #endif 585 if (p->p_stat) { 586 if (*mode == 'o') { 587 if (p->p_stat != SONPROC) 588 continue; 589 if (p->p_cpu != NULL && p->p_cpu-> 590 ci_schedstate.spc_idleproc == p) 591 continue; 592 } 593 594 if (*mode == 'n') { 595 db_printf("%c%5d ", (p == curproc ? 596 '*' : ' '), pr->ps_pid); 597 } else { 598 db_printf("%c%6d ", (p == curproc ? 599 '*' : ' '), p->p_tid); 600 } 601 602 switch (*mode) { 603 604 case 'a': 605 db_printf("%-9.9s %18p %18p %18p\n", 606 pr->ps_comm, p, p->p_addr, p->p_vmspace); 607 break; 608 609 case 'n': 610 db_printf("%6d %5d %5d %d %#10x " 611 "%-12.12s %-15s\n", 612 p->p_tid, ppr ? ppr->ps_pid : -1, 613 pr->ps_ucred->cr_ruid, p->p_stat, 614 p->p_flag | pr->ps_flags, 615 (p->p_wchan && p->p_wmesg) ? 616 p->p_wmesg : "", pr->ps_comm); 617 break; 618 619 case 'w': 620 db_printf("%-15s %-5d %18p %s\n", 621 pr->ps_comm, (pr->ps_pgrp ? 622 pr->ps_pgrp->pg_id : -1), 623 p->p_wchan, 624 (p->p_wchan && p->p_wmesg) ? 625 p->p_wmesg : ""); 626 break; 627 628 case 'o': 629 db_printf("%5d %5d %#10x %#10x %3d" 630 "%c %-31s\n", 631 pr->ps_pid, pr->ps_ucred->cr_ruid, 632 pr->ps_flags, p->p_flag, 633 CPU_INFO_UNIT(p->p_cpu), 634 has_kernel_lock ? 'K' : ' ', 635 pr->ps_comm); 636 break; 637 638 } 639 } 640 } 641 pr = LIST_NEXT(pr, ps_list); 642 if (pr == NULL && skipzomb == 0) { 643 skipzomb = 1; 644 pr = LIST_FIRST(&zombprocess); 645 } 646 } 647 } 648 #endif 649 650 #ifdef DEBUG 651 void 652 pgrpdump(void) 653 { 654 struct pgrp *pgrp; 655 struct process *pr; 656 int i; 657 658 for (i = 0; i <= pgrphash; i++) { 659 if (!LIST_EMPTY(&pgrphashtbl[i])) { 660 printf("\tindx %d\n", i); 661 LIST_FOREACH(pgrp, &pgrphashtbl[i], pg_hash) { 662 printf("\tpgrp %p, pgid %d, sess %p, sesscnt %d, mem %p\n", 663 pgrp, pgrp->pg_id, pgrp->pg_session, 664 pgrp->pg_session->s_count, 665 LIST_FIRST(&pgrp->pg_members)); 666 LIST_FOREACH(pr, &pgrp->pg_members, ps_pglist) { 667 printf("\t\tpid %d addr %p pgrp %p\n", 668 pr->ps_pid, pr, pr->ps_pgrp); 669 } 670 } 671 } 672 } 673 } 674 #endif /* DEBUG */ 675