1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ 27 /* All Rights Reserved */ 28 29 30 #pragma ident "%Z%%M% %I% %E% SMI" 31 32 #include <sys/param.h> 33 #include <sys/types.h> 34 #include <sys/time.h> 35 #include <sys/sysmacros.h> 36 #include <sys/proc.h> 37 #include <sys/systm.h> 38 #include <sys/cred.h> 39 #include <sys/user.h> 40 #include <sys/utsname.h> 41 #include <sys/errno.h> 42 #include <sys/signal.h> 43 #include <sys/siginfo.h> 44 #include <sys/fault.h> 45 #include <sys/syscall.h> 46 #include <sys/ucontext.h> 47 #include <sys/prsystm.h> 48 #include <sys/vnode.h> 49 #include <sys/var.h> 50 #include <sys/file.h> 51 #include <sys/pathname.h> 52 #include <sys/vfs.h> 53 #include <sys/exec.h> 54 #include <sys/debug.h> 55 #include <sys/stack.h> 56 #include <sys/kmem.h> 57 #include <sys/schedctl.h> 58 #include <sys/core.h> 59 #include <sys/corectl.h> 60 #include <sys/cmn_err.h> 61 #include <vm/as.h> 62 #include <sys/rctl.h> 63 #include <sys/nbmlock.h> 64 #include <sys/stat.h> 65 #include <sys/zone.h> 66 #include <sys/contract/process_impl.h> 67 68 /* 69 * Processes running within a zone potentially dump core in 3 locations, 70 * based on the per-process, per-zone, and the global zone's core settings. 71 * 72 * Per-zone and global zone settings are often referred to as "global" 73 * settings since they apply to the system (or zone) as a whole, as 74 * opposed to a particular process. 75 */ 76 enum core_types { 77 CORE_PROC, /* Use per-process settings */ 78 CORE_ZONE, /* Use per-zone settings */ 79 CORE_GLOBAL /* Use global zone settings */ 80 }; 81 82 /* 83 * Log information about "global" core dumps to syslog. 84 */ 85 static void 86 core_log(struct core_globals *cg, int error, const char *why, const char *path, 87 zoneid_t zoneid) 88 { 89 proc_t *p = curproc; 90 pid_t pid = p->p_pid; 91 char *fn = PTOU(p)->u_comm; 92 93 if (!(cg->core_options & CC_GLOBAL_LOG)) 94 return; 95 96 if (path == NULL) 97 zcmn_err(zoneid, CE_NOTE, "core_log: %s[%d] %s", fn, pid, why); 98 else if (error == 0) 99 zcmn_err(zoneid, CE_NOTE, "core_log: %s[%d] %s: %s", fn, pid, 100 why, path); 101 else 102 zcmn_err(zoneid, CE_NOTE, "core_log: %s[%d] %s, errno=%d: %s", 103 fn, pid, why, error, path); 104 } 105 106 /* 107 * Private version of vn_remove(). 108 * Refuse to unlink a directory or an unwritable file. 109 * Also allow the process to access files normally inaccessible due to 110 * chroot(2) or Zone limitations. 111 */ 112 static int 113 remove_core_file(char *fp, enum core_types core_type) 114 { 115 vnode_t *vp = NULL; /* entry vnode */ 116 vnode_t *dvp; /* ptr to parent dir vnode */ 117 vfs_t *dvfsp; 118 int error; 119 int in_crit = 0; 120 pathname_t pn; /* name of entry */ 121 vnode_t *startvp, *rootvp; 122 123 if ((error = pn_get(fp, UIO_SYSSPACE, &pn)) != 0) 124 return (error); 125 /* 126 * Determine what rootvp to use. 127 */ 128 if (core_type == CORE_PROC) { 129 rootvp = (PTOU(curproc)->u_rdir == NULL ? 130 curproc->p_zone->zone_rootvp : PTOU(curproc)->u_rdir); 131 startvp = (fp[0] == '/' ? rootvp : PTOU(curproc)->u_cdir); 132 } else if (core_type == CORE_ZONE) { 133 startvp = curproc->p_zone->zone_rootvp; 134 rootvp = curproc->p_zone->zone_rootvp; 135 } else { 136 ASSERT(core_type == CORE_GLOBAL); 137 startvp = rootdir; 138 rootvp = rootdir; 139 } 140 VN_HOLD(startvp); 141 if (rootvp != rootdir) 142 VN_HOLD(rootvp); 143 if ((error = lookuppnvp(&pn, NULL, NO_FOLLOW, &dvp, &vp, rootvp, 144 startvp, CRED())) != 0) { 145 pn_free(&pn); 146 return (error); 147 } 148 /* 149 * Succeed if there is no file. 150 * Fail if the file is not a regular file. 151 * Fail if the filesystem is mounted read-only. 152 * Fail if the file is not writeable. 153 * Fail if the file has NBMAND share reservations. 154 */ 155 if (vp == NULL) 156 error = 0; 157 else if (vp->v_type != VREG) 158 error = EACCES; 159 else if ((dvfsp = dvp->v_vfsp) != NULL && 160 (dvfsp->vfs_flag & VFS_RDONLY)) 161 error = EROFS; 162 else if ((error = VOP_ACCESS(vp, VWRITE, 0, CRED())) == 0) { 163 if (nbl_need_check(vp)) { 164 nbl_start_crit(vp, RW_READER); 165 in_crit = 1; 166 if (nbl_share_conflict(vp, NBL_REMOVE)) { 167 error = EACCES; 168 } 169 } 170 if (!error) { 171 error = VOP_REMOVE(dvp, pn.pn_path, CRED()); 172 } 173 } 174 175 pn_free(&pn); 176 if (vp != NULL) { 177 if (in_crit) 178 nbl_end_crit(vp); 179 VN_RELE(vp); 180 } 181 VN_RELE(dvp); 182 return (error); 183 } 184 185 /* 186 * Create the core file in a location that may be normally inaccessible due 187 * to chroot(2) or Zone limitations. 188 */ 189 static int 190 create_core_file(char *fp, enum core_types core_type, vnode_t **vpp) 191 { 192 int error; 193 mode_t perms = (S_IRUSR | S_IWUSR); 194 pathname_t pn; 195 char *file; 196 vnode_t *vp; 197 vnode_t *dvp; 198 vattr_t vattr; 199 cred_t *credp = CRED(); 200 201 if (core_type == CORE_PROC) { 202 file = fp; 203 dvp = NULL; /* regular lookup */ 204 } else { 205 vnode_t *startvp, *rootvp; 206 207 ASSERT(core_type == CORE_ZONE || core_type == CORE_GLOBAL); 208 /* 209 * This is tricky because we want to dump the core in 210 * a location which may normally be inaccessible 211 * to us (due to chroot(2) limitations, or zone 212 * membership), and hence need to overcome u_rdir 213 * restrictions. The basic idea is to separate 214 * the path from the filename, lookup the 215 * pathname separately (starting from the global 216 * zone's root directory), and then open the 217 * file starting at the directory vnode. 218 */ 219 if (error = pn_get(fp, UIO_SYSSPACE, &pn)) 220 return (error); 221 222 if (core_type == CORE_ZONE) { 223 startvp = rootvp = curproc->p_zone->zone_rootvp; 224 } else { 225 startvp = rootvp = rootdir; 226 } 227 /* 228 * rootvp and startvp will be VN_RELE()'d by lookuppnvp() if 229 * necessary. 230 */ 231 VN_HOLD(startvp); 232 if (rootvp != rootdir) 233 VN_HOLD(rootvp); 234 /* 235 * Do a lookup on the full path, ignoring the actual file, but 236 * finding the vnode for the directory. It's OK if the file 237 * doesn't exist -- it most likely won't since we just removed 238 * it. 239 */ 240 error = lookuppnvp(&pn, NULL, FOLLOW, &dvp, NULLVPP, 241 rootvp, startvp, credp); 242 pn_free(&pn); 243 if (error != 0) 244 return (error); 245 ASSERT(dvp != NULL); 246 /* 247 * Now find the final component in the path (ie, the name of 248 * the core file). 249 */ 250 if (error = pn_get(fp, UIO_SYSSPACE, &pn)) { 251 VN_RELE(dvp); 252 return (error); 253 } 254 pn_setlast(&pn); 255 file = pn.pn_path; 256 } 257 error = vn_openat(file, UIO_SYSSPACE, FWRITE | FTRUNC | FEXCL | 258 FCREAT | FOFFMAX, perms, &vp, CRCREAT, PTOU(curproc)->u_cmask, dvp); 259 if (core_type != CORE_PROC) { 260 VN_RELE(dvp); 261 pn_free(&pn); 262 } 263 /* 264 * Don't dump a core file owned by "nobody". 265 */ 266 vattr.va_mask = AT_UID; 267 if (error == 0 && 268 (VOP_GETATTR(vp, &vattr, 0, credp) != 0 || 269 vattr.va_uid != crgetuid(credp))) { 270 (void) VOP_CLOSE(vp, FWRITE, 1, (offset_t)0, 271 credp); 272 VN_RELE(vp); 273 (void) remove_core_file(fp, core_type); 274 error = EACCES; 275 } 276 *vpp = vp; 277 return (error); 278 } 279 280 /* 281 * Install the specified held cred into the process, and return a pointer to 282 * the held cred which was previously the value of p->p_cred. 283 */ 284 static cred_t * 285 set_cred(proc_t *p, cred_t *newcr) 286 { 287 cred_t *oldcr; 288 uid_t olduid, newuid; 289 290 /* 291 * Place a hold on the existing cred, and then install the new 292 * cred into the proc structure. 293 */ 294 mutex_enter(&p->p_crlock); 295 oldcr = p->p_cred; 296 crhold(oldcr); 297 p->p_cred = newcr; 298 mutex_exit(&p->p_crlock); 299 300 ASSERT(crgetzoneid(oldcr) == crgetzoneid(newcr)); 301 302 /* 303 * If the real uid is changing, keep the per-user process 304 * counts accurate. 305 */ 306 olduid = crgetruid(oldcr); 307 newuid = crgetruid(newcr); 308 if (olduid != newuid) { 309 zoneid_t zoneid = crgetzoneid(newcr); 310 311 mutex_enter(&pidlock); 312 upcount_dec(olduid, zoneid); 313 upcount_inc(newuid, zoneid); 314 mutex_exit(&pidlock); 315 } 316 317 /* 318 * Broadcast the new cred to all the other threads. The old 319 * cred can be safely returned because we have a hold on it. 320 */ 321 crset(p, newcr); 322 return (oldcr); 323 } 324 325 static int 326 do_core(char *fp, int sig, enum core_types core_type, struct core_globals *cg) 327 { 328 proc_t *p = curproc; 329 cred_t *credp = CRED(); 330 rlim64_t rlimit; 331 vnode_t *vp; 332 int error = 0; 333 struct execsw *eswp; 334 cred_t *ocredp = NULL; 335 int is_setid = 0; 336 core_content_t content; 337 uid_t uid; 338 gid_t gid; 339 340 if (core_type == CORE_GLOBAL || core_type == CORE_ZONE) { 341 mutex_enter(&cg->core_lock); 342 content = cg->core_content; 343 mutex_exit(&cg->core_lock); 344 rlimit = cg->core_rlimit; 345 } else { 346 mutex_enter(&p->p_lock); 347 rlimit = rctl_enforced_value(rctlproc_legacy[RLIMIT_CORE], 348 p->p_rctls, p); 349 content = corectl_content_value(p->p_content); 350 mutex_exit(&p->p_lock); 351 } 352 353 if (rlimit == 0) 354 return (EFBIG); 355 356 /* 357 * If SNOCD is set, or if the effective, real, and saved ids do 358 * not match up, no one but a privileged user is allowed to view 359 * this core file. Set the credentials and the owner to root. 360 */ 361 if ((p->p_flag & SNOCD) || 362 (uid = crgetuid(credp)) != crgetruid(credp) || 363 uid != crgetsuid(credp) || 364 (gid = crgetgid(credp)) != crgetrgid(credp) || 365 gid != crgetsgid(credp)) { 366 /* 367 * Because this is insecure against certain forms of file 368 * system attack, do it only if set-id core files have been 369 * enabled via corectl(CC_GLOBAL_SETID | CC_PROCESS_SETID). 370 */ 371 if (((core_type == CORE_GLOBAL || core_type == CORE_ZONE) && 372 !(cg->core_options & CC_GLOBAL_SETID)) || 373 (core_type == CORE_PROC && 374 !(cg->core_options & CC_PROCESS_SETID))) 375 return (ENOTSUP); 376 377 is_setid = 1; 378 } 379 380 /* 381 * If we are doing a "global" core dump or a set-id core dump, 382 * use kcred to do the dumping. 383 */ 384 if (core_type == CORE_GLOBAL || core_type == CORE_ZONE || is_setid) { 385 /* 386 * Use the zone's "kcred" to prevent privilege 387 * escalation. 388 */ 389 credp = zone_get_kcred(getzoneid()); 390 ASSERT(credp != NULL); 391 ocredp = set_cred(p, credp); 392 } 393 394 /* 395 * First remove any existing core file, then 396 * open the new core file with (O_EXCL|O_CREAT). 397 * 398 * The reasons for doing this are manifold: 399 * 400 * For security reasons, we don't want root processes 401 * to dump core through a symlink because that would 402 * allow a malicious user to clobber any file on 403 * the system if s/he could convince a root process, 404 * perhaps a set-uid root process that s/he started, 405 * to dump core in a directory writable by that user. 406 * Similar security reasons apply to hard links. 407 * For symmetry we do this unconditionally, not 408 * just for root processes. 409 * 410 * If the process has the core file mmap()d into the 411 * address space, we would be modifying the address 412 * space that we are trying to dump if we did not first 413 * remove the core file. (The command "file core" 414 * is the canonical example of this possibility.) 415 * 416 * Opening the core file with O_EXCL|O_CREAT ensures than 417 * two concurrent core dumps don't clobber each other. 418 * One is bound to lose; we don't want to make both lose. 419 */ 420 if ((error = remove_core_file(fp, core_type)) == 0) { 421 error = create_core_file(fp, core_type, &vp); 422 } 423 424 /* 425 * Now that vn_open is complete, reset the process's credentials if 426 * we changed them, and make 'credp' point to kcred used 427 * above. We use 'credp' to do i/o on the core file below, but leave 428 * p->p_cred set to the original credential to allow the core file 429 * to record this information. 430 */ 431 if (ocredp != NULL) 432 credp = set_cred(p, ocredp); 433 434 if (error == 0) { 435 int closerr; 436 #if defined(__sparc) 437 (void) flush_user_windows_to_stack(NULL); 438 #endif 439 #ifdef SUN_SRC_COMPAT 440 PTOU(curproc)->u_acflag |= ACORE; 441 #endif 442 if ((eswp = PTOU(curproc)->u_execsw) == NULL || 443 (eswp = findexec_by_magic(eswp->exec_magic)) == NULL) { 444 error = ENOSYS; 445 } else { 446 error = eswp->exec_core(vp, p, credp, rlimit, sig, 447 content); 448 rw_exit(eswp->exec_lock); 449 } 450 451 closerr = VOP_CLOSE(vp, FWRITE, 1, (offset_t)0, credp); 452 VN_RELE(vp); 453 if (error == 0) 454 error = closerr; 455 } 456 457 if (ocredp != NULL) 458 crfree(credp); 459 460 return (error); 461 } 462 463 /* 464 * Convert a core name pattern to a pathname. 465 */ 466 static int 467 expand_string(const char *pat, char *fp, int size, cred_t *cr) 468 { 469 proc_t *p = curproc; 470 char buf[24]; 471 int len, i; 472 char *s; 473 char c; 474 475 while ((c = *pat++) != '\0') { 476 if (size < 2) 477 return (ENAMETOOLONG); 478 if (c != '%') { 479 size--; 480 *fp++ = c; 481 continue; 482 } 483 if ((c = *pat++) == '\0') { 484 size--; 485 *fp++ = '%'; 486 break; 487 } 488 switch (c) { 489 case 'p': /* pid */ 490 (void) sprintf((s = buf), "%d", p->p_pid); 491 break; 492 case 'u': /* effective uid */ 493 (void) sprintf((s = buf), "%d", crgetuid(p->p_cred)); 494 break; 495 case 'g': /* effective gid */ 496 (void) sprintf((s = buf), "%d", crgetgid(p->p_cred)); 497 break; 498 case 'f': /* exec'd filename */ 499 s = PTOU(p)->u_comm; 500 break; 501 case 'd': /* exec'd dirname */ 502 /* 503 * Even if pathname caching is disabled, we should 504 * be able to lookup the pathname for a directory. 505 */ 506 if (p->p_execdir != NULL && vnodetopath(NULL, 507 p->p_execdir, fp, size, cr) == 0) { 508 len = (int)strlen(fp); 509 ASSERT(len < size); 510 ASSERT(len >= 1); 511 ASSERT(fp[0] == '/'); 512 513 /* 514 * Strip off the leading slash. 515 */ 516 for (i = 0; i < len; i++) { 517 fp[i] = fp[i + 1]; 518 } 519 520 len--; 521 522 size -= len; 523 fp += len; 524 } else { 525 *fp = '\0'; 526 } 527 528 continue; 529 case 'n': /* system nodename */ 530 s = uts_nodename(); 531 break; 532 case 'm': /* machine (sun4u, etc) */ 533 s = utsname.machine; 534 break; 535 case 't': /* decimal value of time(2) */ 536 (void) sprintf((s = buf), "%ld", gethrestime_sec()); 537 break; 538 case 'z': 539 s = p->p_zone->zone_name; 540 break; 541 case '%': 542 (void) strcpy((s = buf), "%"); 543 break; 544 default: 545 s = buf; 546 buf[0] = '%'; 547 buf[1] = c; 548 buf[2] = '\0'; 549 break; 550 } 551 len = (int)strlen(s); 552 if ((size -= len) <= 0) 553 return (ENAMETOOLONG); 554 (void) strcpy(fp, s); 555 fp += len; 556 } 557 558 *fp = '\0'; 559 return (0); 560 } 561 562 static int 563 dump_one_core(int sig, rlim64_t rlimit, enum core_types core_type, 564 struct core_globals *cg, char **name) 565 { 566 refstr_t *rp; 567 proc_t *p = curproc; 568 zoneid_t zoneid; 569 int error; 570 char *fp; 571 cred_t *cr; 572 573 ASSERT(core_type == CORE_ZONE || core_type == CORE_GLOBAL); 574 zoneid = (core_type == CORE_ZONE ? getzoneid() : GLOBAL_ZONEID); 575 576 mutex_enter(&cg->core_lock); 577 if ((rp = cg->core_file) != NULL) 578 refstr_hold(rp); 579 mutex_exit(&cg->core_lock); 580 if (rp == NULL) { 581 core_log(cg, 0, "no global core file pattern exists", NULL, 582 zoneid); 583 return (1); /* core file not generated */ 584 } 585 fp = kmem_alloc(MAXPATHLEN, KM_SLEEP); 586 cr = zone_get_kcred(getzoneid()); 587 error = expand_string(refstr_value(rp), fp, MAXPATHLEN, cr); 588 crfree(cr); 589 if (error != 0) { 590 core_log(cg, 0, "global core file pattern too long", 591 refstr_value(rp), zoneid); 592 } else if ((error = do_core(fp, sig, core_type, cg)) == 0) { 593 core_log(cg, 0, "core dumped", fp, zoneid); 594 } else if (error == ENOTSUP) { 595 core_log(cg, 0, "setid process, core not dumped", fp, zoneid); 596 } else if (error == ENOSPC) { 597 core_log(cg, 0, "no space left on device, core truncated", 598 fp, zoneid); 599 } else if (error == EFBIG) { 600 if (rlimit == 0) 601 core_log(cg, 0, "core rlimit is zero, core not dumped", 602 fp, zoneid); 603 else 604 core_log(cg, 0, "core rlimit exceeded, core truncated", 605 fp, zoneid); 606 /* 607 * In addition to the core result logging, we 608 * may also have explicit actions defined on 609 * core file size violations via the resource 610 * control framework. 611 */ 612 mutex_enter(&p->p_lock); 613 (void) rctl_action(rctlproc_legacy[RLIMIT_CORE], 614 p->p_rctls, p, RCA_SAFE); 615 mutex_exit(&p->p_lock); 616 } else { 617 core_log(cg, error, "core dump failed", fp, zoneid); 618 } 619 refstr_rele(rp); 620 if (name != NULL) 621 *name = fp; 622 else 623 kmem_free(fp, MAXPATHLEN); 624 return (error); 625 } 626 627 int 628 core(int sig, int ext) 629 { 630 proc_t *p = curproc; 631 klwp_t *lwp = ttolwp(curthread); 632 refstr_t *rp; 633 char *fp_process = NULL, *fp_global = NULL, *fp_zone = NULL; 634 int error1 = 1; 635 int error2 = 1; 636 int error3 = 1; 637 k_sigset_t sigmask; 638 k_sigset_t sighold; 639 rlim64_t rlimit; 640 struct core_globals *my_cg, *global_cg; 641 642 global_cg = zone_getspecific(core_zone_key, global_zone); 643 ASSERT(global_cg != NULL); 644 645 my_cg = zone_getspecific(core_zone_key, curproc->p_zone); 646 ASSERT(my_cg != NULL); 647 648 /* core files suppressed? */ 649 if (!(my_cg->core_options & (CC_PROCESS_PATH|CC_GLOBAL_PATH)) && 650 !(global_cg->core_options & CC_GLOBAL_PATH)) { 651 if (!ext && p->p_ct_process != NULL) 652 contract_process_core(p->p_ct_process, p, sig, 653 NULL, NULL, NULL); 654 return (1); 655 } 656 657 /* 658 * Block all signals except SIGHUP, SIGINT, SIGKILL, and SIGTERM. 659 * These signals are allowed to interrupt the core dump. 660 * SIGQUIT is not allowed because it is supposed to make a core. 661 * Additionally, get current limit on core file size for handling later 662 * error reporting. 663 */ 664 mutex_enter(&p->p_lock); 665 666 p->p_flag |= SDOCORE; 667 schedctl_finish_sigblock(curthread); 668 sigmask = curthread->t_hold; /* remember for later */ 669 sigfillset(&sighold); 670 if (!sigismember(&sigmask, SIGHUP)) 671 sigdelset(&sighold, SIGHUP); 672 if (!sigismember(&sigmask, SIGINT)) 673 sigdelset(&sighold, SIGINT); 674 if (!sigismember(&sigmask, SIGKILL)) 675 sigdelset(&sighold, SIGKILL); 676 if (!sigismember(&sigmask, SIGTERM)) 677 sigdelset(&sighold, SIGTERM); 678 curthread->t_hold = sighold; 679 680 rlimit = rctl_enforced_value(rctlproc_legacy[RLIMIT_CORE], p->p_rctls, 681 p); 682 683 mutex_exit(&p->p_lock); 684 685 /* 686 * Undo any watchpoints. 687 */ 688 pr_free_watched_pages(p); 689 690 /* 691 * The presence of a current signal prevents file i/o 692 * from succeeding over a network. We copy the current 693 * signal information to the side and cancel the current 694 * signal so that the core dump will succeed. 695 */ 696 ASSERT(lwp->lwp_cursig == sig); 697 lwp->lwp_cursig = 0; 698 lwp->lwp_extsig = 0; 699 if (lwp->lwp_curinfo == NULL) 700 bzero(&lwp->lwp_siginfo, sizeof (k_siginfo_t)); 701 else { 702 bcopy(&lwp->lwp_curinfo->sq_info, 703 &lwp->lwp_siginfo, sizeof (k_siginfo_t)); 704 siginfofree(lwp->lwp_curinfo); 705 lwp->lwp_curinfo = NULL; 706 } 707 708 /* 709 * Convert the core file name patterns into path names 710 * and call do_core() to write the core files. 711 */ 712 713 if (my_cg->core_options & CC_PROCESS_PATH) { 714 mutex_enter(&p->p_lock); 715 if (p->p_corefile != NULL) 716 rp = corectl_path_value(p->p_corefile); 717 else 718 rp = NULL; 719 mutex_exit(&p->p_lock); 720 if (rp != NULL) { 721 fp_process = kmem_alloc(MAXPATHLEN, KM_SLEEP); 722 error1 = expand_string(refstr_value(rp), 723 fp_process, MAXPATHLEN, p->p_cred); 724 if (error1 == 0) 725 error1 = do_core(fp_process, sig, CORE_PROC, 726 my_cg); 727 refstr_rele(rp); 728 } 729 } 730 731 if (my_cg->core_options & CC_GLOBAL_PATH) 732 error2 = dump_one_core(sig, rlimit, CORE_ZONE, my_cg, 733 &fp_global); 734 if (global_cg != my_cg && (global_cg->core_options & CC_GLOBAL_PATH)) 735 error3 = dump_one_core(sig, rlimit, CORE_GLOBAL, global_cg, 736 &fp_zone); 737 738 /* 739 * Restore the signal hold mask. 740 */ 741 mutex_enter(&p->p_lock); 742 curthread->t_hold = sigmask; 743 mutex_exit(&p->p_lock); 744 745 if (!ext && p->p_ct_process != NULL) 746 contract_process_core(p->p_ct_process, p, sig, 747 error1 == 0 ? fp_process : NULL, 748 error2 == 0 ? fp_global : NULL, 749 error3 == 0 ? fp_zone : NULL); 750 751 if (fp_process != NULL) 752 kmem_free(fp_process, MAXPATHLEN); 753 if (fp_global != NULL) 754 kmem_free(fp_global, MAXPATHLEN); 755 if (fp_zone != NULL) 756 kmem_free(fp_zone, MAXPATHLEN); 757 758 /* 759 * Return non-zero if no core file was created. 760 */ 761 return (error1 != 0 && error2 != 0 && error3 != 0); 762 } 763 764 /* 765 * Maximum chunk size for dumping core files, 766 * size in pages, patchable in /etc/system 767 */ 768 uint_t core_chunk = 32; 769 770 /* 771 * Common code to core dump process memory. The core_seg routine does i/o 772 * using core_write() below, and so it has the same failure semantics. 773 */ 774 int 775 core_seg(proc_t *p, vnode_t *vp, offset_t offset, caddr_t addr, size_t size, 776 rlim64_t rlimit, cred_t *credp) 777 { 778 caddr_t eaddr; 779 caddr_t base; 780 size_t len; 781 int err = 0; 782 783 eaddr = addr + size; 784 for (base = addr; base < eaddr; base += len) { 785 len = eaddr - base; 786 if (as_memory(p->p_as, &base, &len) != 0) 787 return (0); 788 /* 789 * Reduce len to a reasonable value so that we don't 790 * overwhelm the VM system with a monstrously large 791 * single write and cause pageout to stop running. 792 */ 793 if (len > (size_t)core_chunk * PAGESIZE) 794 len = (size_t)core_chunk * PAGESIZE; 795 796 err = core_write(vp, UIO_USERSPACE, 797 offset + (size_t)(base - addr), base, len, rlimit, credp); 798 799 if (err == 0) { 800 /* 801 * Give pageout a chance to run. 802 * Also allow core dumping to be interruptible. 803 */ 804 err = delay_sig(1); 805 } 806 if (err) 807 return (err); 808 } 809 return (0); 810 } 811 812 /* 813 * Wrapper around vn_rdwr to perform writes to a core file. For core files, 814 * we always want to write as much as we possibly can, and then make sure to 815 * return either 0 to the caller (for success), or the actual errno value. 816 * By using this function, the caller can omit additional code for handling 817 * retries and errors for partial writes returned by vn_rdwr. If vn_rdwr 818 * unexpectedly returns zero but no progress has been made, we return ENOSPC. 819 */ 820 int 821 core_write(vnode_t *vp, enum uio_seg segflg, offset_t offset, 822 const void *buf, size_t len, rlim64_t rlimit, cred_t *credp) 823 { 824 ssize_t resid = len; 825 int error = 0; 826 827 while (len != 0) { 828 error = vn_rdwr(UIO_WRITE, vp, (caddr_t)buf, len, offset, 829 segflg, 0, rlimit, credp, &resid); 830 831 if (error != 0) 832 break; 833 834 if (resid >= len) 835 return (ENOSPC); 836 837 buf = (const char *)buf + len - resid; 838 offset += len - resid; 839 len = resid; 840 } 841 842 return (error); 843 } 844