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 /* 23 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* 28 * Remove objects. Objects need removal from a process as part of: 29 * 30 * o a dlclose() request 31 * 32 * o tearing down a dlopen(), lazy-load, or filter hierarchy that failed to 33 * completely load 34 * 35 * Any other failure condition will result in process exit (in which case all 36 * we have to do is execute the fini's - tear down is unnecessary). 37 * 38 * Any removal of objects is therefore associated with a dlopen() handle. There 39 * is a small window between creation of the first dlopen() object and creating 40 * its handle (in which case remove_so() can get rid of the new link-map if 41 * necessary), but other than this all object removal is driven by inspecting 42 * the components of a handle. 43 * 44 * Things to note. The creation of a link-map, and its addition to the link-map 45 * list occurs in {elf|aout}_new_lm(), if this returns success the link-map is 46 * valid and added, otherwise any steps (allocations) in the process of creating 47 * the link-map would have been undone. If a failure occurs between creating 48 * the link-map and adding it to a handle, remove_so() is called to remove the 49 * link-map. If a failures occurs after a handle have been created, 50 * remove_hdl() is called to remove the handle and the link-map. 51 */ 52 53 #include <string.h> 54 #include <stdio.h> 55 #include <unistd.h> 56 #include <dlfcn.h> 57 #include <sys/debug.h> 58 #include <sys/avl.h> 59 #include <libc_int.h> 60 #include <debug.h> 61 #include "_rtld.h" 62 #include "_audit.h" 63 #include "_elf.h" 64 #include "msg.h" 65 66 /* 67 * Atexit callback provided by libc. As part of dlclose() determine the address 68 * ranges of all objects that are to be deleted. Pass this information to 69 * libc's pre-atexit routine. Libc will purge any registered atexit() calls 70 * related to those objects about to be deleted. 71 */ 72 static int 73 purge_exit_handlers(Lm_list *lml, Rt_map **tobj) 74 { 75 uint_t num; 76 Rt_map **_tobj; 77 Lc_addr_range_t *addr, *_addr; 78 int error; 79 int (*fptr)(Lc_addr_range_t *, uint_t); 80 81 /* 82 * Has a callback been established? 83 */ 84 if ((fptr = lml->lm_lcs[CI_ATEXIT].lc_un.lc_func) == NULL) 85 return (0); 86 87 /* 88 * Determine the total number of mapped segments that will be unloaded. 89 */ 90 for (num = 0, _tobj = tobj; *_tobj != NULL; _tobj++) { 91 Rt_map *lmp = *_tobj; 92 93 num += MMAPCNT(lmp); 94 } 95 96 /* 97 * Account for a null entry at the end of the address range array. 98 */ 99 if (num++ == 0) 100 return (0); 101 102 /* 103 * Allocate an array for the address range. 104 */ 105 if ((addr = malloc(num * sizeof (Lc_addr_range_t))) == NULL) 106 return (1); 107 108 /* 109 * Fill the address range with each loadable segments size and address. 110 */ 111 for (_tobj = tobj, _addr = addr; *_tobj != NULL; _tobj++) { 112 Rt_map *lmp = *_tobj; 113 mmapobj_result_t *mpp = MMAPS(lmp); 114 uint_t ndx; 115 116 for (ndx = 0; ndx < MMAPCNT(lmp); ndx++, mpp++) { 117 _addr->lb = (void *)(uintptr_t)(mpp->mr_addr + 118 mpp->mr_offset); 119 _addr->ub = (void *)(uintptr_t)(mpp->mr_addr + 120 mpp->mr_msize); 121 _addr++; 122 } 123 } 124 _addr->lb = _addr->ub = 0; 125 126 leave(LIST(*tobj), 0); 127 error = (*fptr)(addr, (num - 1)); 128 (void) enter(0); 129 130 /* 131 * If we fail to converse with libc, generate an error message to 132 * satisfy any dlerror() usage. 133 */ 134 if (error) 135 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_ATEXIT), error); 136 137 free(addr); 138 return (error); 139 } 140 141 /* 142 * Break down an Alist containing pathname descriptors. In most instances, the 143 * Alist is cleaned of all entries, but retained for later use. 144 */ 145 void 146 remove_plist(Alist **alpp, int complete) 147 { 148 Alist *alp = *alpp; 149 150 if (alp) { 151 if (complete) { 152 free((void *)alp); 153 *alpp = NULL; 154 } else { 155 alp->al_nitems = 0; 156 alp->al_next = ALIST_OFF_DATA; 157 } 158 } 159 } 160 161 /* 162 * Remove a link-map list descriptor. This is called to finalize the removal 163 * of an entire link-map list, after all link-maps have been removed, or none 164 * got added. As load_one() can process a list of potential candidate objects, 165 * the link-map descriptor must be maintained as each object is processed. Only 166 * after all objects have been processed can a failure condition finally tear 167 * down the link-map list descriptor. 168 */ 169 void 170 remove_lml(Lm_list *lml) 171 { 172 if (lml && (lml->lm_head == NULL)) { 173 /* 174 * As a whole link-map list is being removed, the debuggers 175 * would have been alerted of this deletion (or an addition 176 * in the case we're here to clean up from a failure). Set 177 * the main link-map list so that a consistent registration 178 * can be signaled to the debuggers when we leave ld.so.1. 179 */ 180 lml_main.lm_flags |= LML_FLG_DBNOTIF; 181 182 if (lml->lm_lmidstr) 183 free(lml->lm_lmidstr); 184 if (lml->lm_alp) 185 free(lml->lm_alp); 186 if (lml->lm_lists) 187 free(lml->lm_lists); 188 if (lml->lm_actaudit) 189 free(lml->lm_actaudit); 190 191 /* 192 * Cleanup any pending RTLDINFO in the case where it was 193 * allocated but not called (see _relocate_lmc()). 194 */ 195 if (lml->lm_rti) 196 free(lml->lm_rti); 197 if (lml->lm_fpavl) { 198 /* 199 * As we are freeing the link-map list, all nodes must 200 * have previously been removed. 201 */ 202 ASSERT(avl_numnodes(lml->lm_fpavl) == 0); 203 free(lml->lm_fpavl); 204 } 205 (void) aplist_delete_value(dynlm_list, lml); 206 free(lml); 207 } 208 } 209 210 /* 211 * Remove a link-map. This removes a link-map from its associated list and 212 * free's up the link-map itself. Note, all components that are freed are local 213 * to the link-map, no inter-link-map lists are operated on as these are all 214 * broken down by dlclose() while all objects are still mapped. 215 * 216 * This routine is called from dlclose() to zap individual link-maps after their 217 * interdependencies (DEPENDS(), CALLER(), handles, etc.) have been removed. 218 * This routine is also called from the bowels of load_one() in the case of a 219 * link-map creation failure. 220 */ 221 void 222 remove_so(Lm_list *lml, Rt_map *lmp) 223 { 224 Dyninfo *dip; 225 226 if (lmp == NULL) 227 return; 228 229 /* 230 * Unlink the link map from the link-map list. 231 */ 232 if (lml && lmp) 233 lm_delete(lml, lmp); 234 235 /* 236 * If this object contributed any local external vectors for the current 237 * link-map list, remove the vectors. If this object contributed any 238 * global external vectors we should find some new candidates, or leave 239 * this object lying around. 240 */ 241 if (lml) { 242 int tag; 243 244 for (tag = 0; tag < CI_MAX; tag++) { 245 if (lml->lm_lcs[tag].lc_lmp == lmp) { 246 lml->lm_lcs[tag].lc_lmp = NULL; 247 lml->lm_lcs[tag].lc_un.lc_val = 0; 248 } 249 if (glcs[tag].lc_lmp == lmp) { 250 ASSERT(glcs[tag].lc_lmp != NULL); 251 glcs[tag].lc_lmp = NULL; 252 glcs[tag].lc_un.lc_val = 0; 253 } 254 } 255 } 256 257 DBG_CALL(Dbg_file_delete(lmp)); 258 259 /* 260 * If this is a temporary link-map, put in place to facilitate the 261 * link-edit or a relocatable object, then the link-map contains no 262 * information that needs to be cleaned up. 263 */ 264 if (FLAGS(lmp) & FLG_RT_OBJECT) 265 return; 266 267 /* 268 * Remove any FullpathNode AVL names if they still exist. 269 */ 270 if (FPNODE(lmp)) 271 fpavl_remove(lmp); 272 273 /* 274 * Remove any alias names. 275 */ 276 if (ALIAS(lmp)) 277 free(ALIAS(lmp)); 278 279 /* 280 * Remove any of this objects filtee infrastructure. The filtees them- 281 * selves have already been removed. 282 */ 283 if (((dip = DYNINFO(lmp)) != NULL) && (FLAGS1(lmp) & MSK_RT_FILTER)) { 284 uint_t cnt, max = DYNINFOCNT(lmp); 285 286 for (cnt = 0; cnt < max; cnt++, dip++) { 287 if ((dip->di_info == NULL) || 288 ((dip->di_flags & MSK_DI_FILTER) == 0)) 289 continue; 290 291 remove_plist((Alist **)&(dip->di_info), 1); 292 } 293 } 294 295 /* 296 * Deallocate any remaining cruft and free the link-map. 297 */ 298 if (RLIST(lmp)) 299 remove_plist(&RLIST(lmp), 1); 300 301 if (AUDITORS(lmp)) 302 audit_desc_cleanup(lmp); 303 if (AUDINFO(lmp)) 304 audit_info_cleanup(lmp); 305 306 /* 307 * Note that COPY_R() and COPY_S() reference the same memory 308 * location, and that we want to release the memory referenced 309 * without regard to which list it logically belongs to. We can 310 * use either pointer to do this. 311 */ 312 if (COPY_R(lmp)) 313 free(COPY_R(lmp)); 314 315 /* 316 * During a dlclose() any groups this object was a part of will have 317 * been torn down. However, we can get here to remove an object that 318 * has failed to load, perhaps because its addition to a handle failed. 319 * Therefore if this object indicates that its part of a group tear 320 * these associations down. 321 */ 322 if (GROUPS(lmp) != NULL) { 323 Aliste idx1; 324 Grp_hdl *ghp; 325 326 for (APLIST_TRAVERSE(GROUPS(lmp), idx1, ghp)) { 327 Grp_desc *gdp; 328 Aliste idx2; 329 330 for (ALIST_TRAVERSE(ghp->gh_depends, idx2, gdp)) { 331 if (gdp->gd_depend != lmp) 332 continue; 333 334 alist_delete(ghp->gh_depends, &idx2); 335 break; 336 } 337 } 338 free(GROUPS(lmp)); 339 } 340 if (HANDLES(lmp)) 341 free(HANDLES(lmp)); 342 343 /* 344 * Clean up reglist if needed 345 */ 346 if (reglist) { 347 Reglist *cur, *prv, *del; 348 349 cur = prv = reglist; 350 while (cur) { 351 if (cur->rl_lmp == lmp) { 352 del = cur; 353 if (cur == reglist) { 354 reglist = cur->rl_next; 355 cur = prv = reglist; 356 } else { 357 prv->rl_next = cur->rl_next; 358 cur = cur->rl_next; 359 } 360 free(del); 361 } else { 362 prv = cur; 363 cur = cur->rl_next; 364 } 365 } 366 } 367 368 /* 369 * If this link map represents a relocatable object concatenation, then 370 * the image was simply generated in allocated memory. Free the memory. 371 * Note: memory maps were fabricated for the relocatable object, and 372 * the mapping infrastructure must be free'd, but there are no address 373 * mappings that must be unmapped. 374 * 375 * Otherwise, unmap the object. 376 */ 377 if (FLAGS(lmp) & FLG_RT_IMGALLOC) 378 free((void *)ADDR(lmp)); 379 380 if (MMAPS(lmp)) { 381 if ((FLAGS(lmp) & FLG_RT_IMGALLOC) == 0) 382 unmap_obj(MMAPS(lmp), MMAPCNT(lmp)); 383 free(MMAPS(lmp)); 384 } 385 386 free(lmp); 387 } 388 389 /* 390 * Traverse an objects dependency list removing callers and dependencies. 391 * There's a chicken and egg problem with tearing down link-maps. Any 392 * relationship between link-maps is maintained on a DEPENDS list, and an 393 * associated CALLERS list. These lists can't be broken down at the time a 394 * single link-map is removed, as any related link-map may have already been 395 * removed. Thus, lists between link-maps must be broken down before the 396 * individual link-maps themselves. 397 */ 398 static void 399 remove_lists(Rt_map *lmp, int lazy) 400 { 401 Aliste idx1; 402 Bnd_desc *bdp; 403 404 /* 405 * First, traverse this objects dependencies. 406 */ 407 for (APLIST_TRAVERSE(DEPENDS(lmp), idx1, bdp)) { 408 Rt_map *dlmp = bdp->b_depend; 409 410 /* 411 * Remove this object from the dependencies callers. 412 */ 413 (void) aplist_delete_value(CALLERS(dlmp), bdp); 414 free(bdp); 415 } 416 if (DEPENDS(lmp)) { 417 free(DEPENDS(lmp)); 418 DEPENDS(lmp) = NULL; 419 } 420 421 /* 422 * Second, traverse this objects callers. 423 */ 424 for (APLIST_TRAVERSE(CALLERS(lmp), idx1, bdp)) { 425 Rt_map *clmp = bdp->b_caller; 426 Dyninfo *dip; 427 428 /* 429 * If we're removing an object that was triggered by a lazyload, 430 * remove the callers DYNINFO() entry and bump the lazy counts. 431 * This reinitialization of the lazy information allows a lazy 432 * object to be reloaded again later. Although we may be 433 * breaking down a group of lazyloaded objects because one has 434 * failed to relocate, it's possible that one or more of the 435 * individual objects can be reloaded without a problem. 436 */ 437 if (lazy && ((dip = DYNINFO(clmp)) != NULL)) { 438 uint_t cnt, max = DYNINFOCNT(clmp); 439 440 for (cnt = 0; cnt < max; cnt++, dip++) { 441 if ((dip->di_flags & FLG_DI_LAZY) == 0) 442 continue; 443 444 if (dip->di_info == (void *)lmp) { 445 dip->di_info = NULL; 446 447 if (LAZY(clmp)++ == 0) 448 LIST(clmp)->lm_lazy++; 449 } 450 } 451 } 452 453 (void) aplist_delete_value(DEPENDS(clmp), bdp); 454 free(bdp); 455 } 456 if (CALLERS(lmp)) { 457 free(CALLERS(lmp)); 458 CALLERS(lmp) = NULL; 459 } 460 } 461 462 /* 463 * Delete any temporary link-map control list. 464 */ 465 void 466 remove_cntl(Lm_list *lml, Aliste lmco) 467 { 468 Aliste _lmco = lmco; 469 #if DEBUG 470 Lm_cntl *lmc; 471 472 lmc = (Lm_cntl *)alist_item_by_offset(lml->lm_lists, lmco); 473 474 /* 475 * This element should be empty. 476 */ 477 ASSERT(lmc->lc_head == NULL); 478 #endif 479 alist_delete_by_offset(lml->lm_lists, &_lmco); 480 } 481 482 /* 483 * If a lazy loaded object, or filtee fails to load, possibly because it, or 484 * one of its dependencies can't be relocated, then tear down any objects 485 * that are apart of this link-map control list. 486 */ 487 static void 488 remove_incomplete(Lm_list *lml, Aliste lmco) 489 { 490 Rt_map *lmp; 491 Lm_cntl *lmc; 492 493 /* LINTED */ 494 lmc = (Lm_cntl *)alist_item_by_offset(lml->lm_lists, lmco); 495 496 /* 497 * First, remove any lists that may point between objects. 498 */ 499 for (lmp = lmc->lc_head; lmp; lmp = NEXT_RT_MAP(lmp)) 500 remove_lists(lmp, 1); 501 502 /* 503 * Finally, remove each object. remove_so() calls lm_delete(), thus 504 * effectively the link-map control head gets updated to point to the 505 * next link-map. 506 */ 507 while ((lmp = lmc->lc_head) != NULL) 508 remove_so(lml, lmp); 509 510 lmc->lc_head = lmc->lc_tail = NULL; 511 } 512 513 /* 514 * Determine whether an object is deletable. 515 */ 516 static int 517 is_deletable(APlist **lmalp, APlist **ghalp, Rt_map *lmp) 518 { 519 Aliste idx; 520 Bnd_desc *bdp; 521 Grp_hdl *ghp; 522 523 /* 524 * If the object hasn't yet been relocated take this as a sign that 525 * it's loading failed, thus we're here to cleanup. If the object is 526 * relocated it will only be retained if it was marked non-deletable, 527 * and exists on the main link-map control list. 528 */ 529 if ((FLAGS(lmp) & FLG_RT_RELOCED) && 530 (MODE(lmp) & RTLD_NODELETE) && (CNTL(lmp) == ALIST_OFF_DATA)) 531 return (0); 532 533 /* 534 * If this object is the head of a handle that has not been captured as 535 * a candidate for deletion, then this object is in use from a dlopen() 536 * outside of the scope of this dlclose() family. Dlopen'ed objects, 537 * and filtees, have group descriptors for their callers. Typically 538 * this parent will have callers that are not apart of this dlclose() 539 * family, and thus would be caught by the CALLERS test below. However, 540 * if the caller had itself been dlopen'ed, it may not have any explicit 541 * callers registered for itself. Thus, but looking for objects with 542 * handles we can ferret out these outsiders. 543 */ 544 for (APLIST_TRAVERSE(HANDLES(lmp), idx, ghp)) { 545 if (aplist_test(ghalp, ghp, 0) != ALE_EXISTS) 546 return (0); 547 } 548 549 /* 550 * If this object is called by any object outside of the family of 551 * objects selected for deletion, it can't be deleted. 552 */ 553 for (APLIST_TRAVERSE(CALLERS(lmp), idx, bdp)) { 554 if (aplist_test(lmalp, bdp->b_caller, 0) != 555 ALE_EXISTS) 556 return (0); 557 } 558 559 /* 560 * This object is a candidate for deletion. 561 */ 562 return (1); 563 } 564 565 /* 566 * Collect the groups (handles) and associated objects that are candidates for 567 * deletion. The criteria for deleting an object is whether it is only refer- 568 * enced from the objects within the groups that are candidates for deletion. 569 */ 570 static int 571 gdp_collect(APlist **ghalpp, APlist **lmalpp, Grp_hdl *ghp1) 572 { 573 Aliste idx1; 574 Grp_desc *gdp; 575 int action; 576 577 /* 578 * Add this group to our group collection. If it isn't added either an 579 * allocation has failed, or it already exists. 580 */ 581 if ((action = aplist_test(ghalpp, ghp1, AL_CNT_GRPCLCT)) != 582 ALE_CREATE) 583 return (action); 584 585 /* 586 * Traverse the dependencies of the group and collect the associated 587 * objects. 588 */ 589 for (ALIST_TRAVERSE(ghp1->gh_depends, idx1, gdp)) { 590 Rt_map *lmp = gdp->gd_depend; 591 592 /* 593 * We only want to process dependencies for deletion. Although 594 * we want to purge group descriptors for parents, we don't want 595 * to analyze the parent itself for additional filters or 596 * deletion. 597 */ 598 if ((gdp->gd_flags & GPD_PARENT) || 599 ((gdp->gd_flags & GPD_ADDEPS) == 0)) 600 continue; 601 602 if ((action = aplist_test(lmalpp, lmp, AL_CNT_GRPCLCT)) == 603 ALE_ALLOCFAIL) 604 return (0); 605 if (action == ALE_EXISTS) 606 continue; 607 608 /* 609 * If this object is a candidate for deletion, determine if the 610 * object provides any filtees. If so, the filter groups are 611 * added to the group collection. 612 * 613 * An object is a candidate for deletion if: 614 * 615 * . the object hasn't yet been relocated, in which case 616 * we're here to clean up a failed load, or 617 * . the object doesn't reside on the base link-map control 618 * list, in which case a group of objects, typically 619 * lazily loaded, or filtees, need cleaning up, or 620 * . the object isn't tagged as non-deletable. 621 */ 622 if ((((FLAGS(lmp) & FLG_RT_RELOCED) == 0) || 623 (CNTL(lmp) != ALIST_OFF_DATA) || 624 ((MODE(lmp) & RTLD_NODELETE) == 0)) && 625 (FLAGS1(lmp) & MSK_RT_FILTER)) { 626 Dyninfo *dip = DYNINFO(lmp); 627 uint_t cnt, max = DYNINFOCNT(lmp); 628 629 for (cnt = 0; cnt < max; cnt++, dip++) { 630 Alist *falp; 631 Aliste idx2; 632 Pdesc *pdp; 633 634 if (((falp = (Alist *)dip->di_info) == NULL) || 635 ((dip->di_flags & MSK_DI_FILTER) == 0)) 636 continue; 637 638 for (ALIST_TRAVERSE(falp, idx2, pdp)) { 639 Grp_hdl *ghp2; 640 641 if ((pdp->pd_plen == 0) || ((ghp2 = 642 (Grp_hdl *)pdp->pd_info) == NULL)) 643 continue; 644 645 if (gdp_collect(ghalpp, lmalpp, 646 ghp2) == 0) 647 return (0); 648 } 649 } 650 } 651 } 652 return (1); 653 } 654 655 /* 656 * Traverse the list of deletable candidates. If an object can't be deleted 657 * then neither can its dependencies or filtees. Any object that is cleared 658 * from being deleted drops the deletion count, plus, if there are no longer 659 * any deletions pending we can discontinue any further processing. 660 */ 661 static int 662 remove_rescan(APlist *lmalp, APlist *ghalp, int *delcnt) 663 { 664 Aliste idx1; 665 Rt_map *lmp; 666 int rescan = 0; 667 668 for (APLIST_TRAVERSE(lmalp, idx1, lmp)) { 669 Aliste idx2; 670 Bnd_desc *bdp; 671 Dyninfo *dip; 672 uint_t cnt, max; 673 674 if (FLAGS(lmp) & FLG_RT_DELETE) 675 continue; 676 677 /* 678 * As this object can't be deleted, make sure its dependencies 679 * aren't deleted either. 680 */ 681 for (APLIST_TRAVERSE(DEPENDS(lmp), idx2, bdp)) { 682 Rt_map *dlmp = bdp->b_depend; 683 684 if (FLAGS(dlmp) & FLG_RT_DELETE) { 685 FLAGS(dlmp) &= ~FLG_RT_DELETE; 686 if (--(*delcnt) == 0) 687 return (0); 688 rescan = 1; 689 } 690 } 691 692 /* 693 * If this object is a filtee and one of its filters is outside 694 * of this dlclose family, then it can't be deleted either. 695 */ 696 if ((FLAGS1(lmp) & MSK_RT_FILTER) == 0) 697 continue; 698 699 dip = DYNINFO(lmp); 700 max = DYNINFOCNT(lmp); 701 702 for (cnt = 0; cnt < max; cnt++, dip++) { 703 Alist *falp; 704 Pdesc *pdp; 705 706 if (((falp = (Alist *)dip->di_info) == NULL) || 707 ((dip->di_flags & MSK_DI_FILTER) == 0)) 708 continue; 709 710 for (ALIST_TRAVERSE(falp, idx2, pdp)) { 711 Aliste idx3; 712 Grp_hdl *ghp; 713 Grp_desc *gdp; 714 715 if ((pdp->pd_plen == 0) || 716 ((ghp = (Grp_hdl *)pdp->pd_info) == NULL)) 717 continue; 718 719 if (aplist_test(&ghalp, ghp, 0) == 720 ALE_EXISTS) 721 continue; 722 723 for (ALIST_TRAVERSE(ghp->gh_depends, idx3, 724 gdp)) { 725 Rt_map *dlmp = gdp->gd_depend; 726 727 if (FLAGS(dlmp) & FLG_RT_DELETE) { 728 FLAGS(dlmp) &= ~FLG_RT_DELETE; 729 if (--(*delcnt) == 0) 730 return (0); 731 rescan = 1; 732 } 733 } 734 735 /* 736 * Remove this group handle from our dynamic 737 * deletion list. 738 */ 739 (void) aplist_delete_value(ghalp, ghp); 740 } 741 } 742 } 743 return (rescan); 744 } 745 746 /* 747 * Cleanup any collection alists we've created. 748 */ 749 static void 750 remove_collect(APlist *ghalp, APlist *lmalp) 751 { 752 if (ghalp) 753 free(ghalp); 754 if (lmalp) 755 free(lmalp); 756 } 757 758 /* 759 * Remove a handle, leaving the associated objects intact. Besides the classic 760 * dlopen() usage, handles are used as a means of associating a group of objects 761 * and promoting modes. Once object promotion is completed, the handle should 762 * be discarded while leaving the associated objects intact. Leaving the handle 763 * would prevent the object from being deleted (as it looks like it's in use 764 * by another user). 765 */ 766 void 767 free_hdl(Grp_hdl *ghp, Rt_map *clmp, uint_t cdflags) 768 { 769 Grp_desc *gdp; 770 Aliste idx; 771 772 if (--(ghp->gh_refcnt) == 0) { 773 uintptr_t ndx; 774 775 for (ALIST_TRAVERSE(ghp->gh_depends, idx, gdp)) { 776 Rt_map *lmp = gdp->gd_depend; 777 778 if (ghp->gh_ownlmp == lmp) 779 (void) aplist_delete_value(HANDLES(lmp), ghp); 780 (void) aplist_delete_value(GROUPS(lmp), ghp); 781 } 782 (void) free(ghp->gh_depends); 783 784 /* LINTED */ 785 ndx = (uintptr_t)ghp % HDLIST_SZ; 786 (void) aplist_delete_value(hdl_alp[ndx], ghp); 787 788 (void) free(ghp); 789 790 } else if (clmp) { 791 /* 792 * It's possible that an RTLD_NOW promotion (via GPD_PROMOTE) 793 * has associated a caller with a handle that is already in use. 794 * In this case, find the caller and either remove the caller 795 * from the handle, or if the caller is used for any other 796 * reason, clear the promotion flag. 797 */ 798 for (ALIST_TRAVERSE(ghp->gh_depends, idx, gdp)) { 799 Rt_map *lmp = gdp->gd_depend; 800 801 if (lmp != clmp) 802 continue; 803 804 if (gdp->gd_flags == cdflags) { 805 alist_delete(ghp->gh_depends, &idx); 806 (void) aplist_delete_value(GROUPS(lmp), ghp); 807 } else { 808 gdp->gd_flags &= ~cdflags; 809 } 810 return; 811 } 812 } 813 } 814 815 /* 816 * If a load operation, using a new link-map control list, has failed, then 817 * forcibly remove the failed objects. This failure can occur as a result 818 * of a lazy load, a dlopen(), or a filtee load, once the application is 819 * running. If the link-map control list has not yet started relocation, then 820 * cleanup is simply a process of removing all the objects from the control 821 * list. If relocation has begun, then other loads may have been triggered to 822 * satisfy the relocations, and thus we need to break down the control list 823 * using handles. 824 * 825 * The objects associated with this load must be part of a unique handle. In 826 * the case of a dlopen() or filtee request, a handle will have been created. 827 * For a lazyload request, a handle must be generated so that the remove 828 * process can use the handle. 829 * 830 * During the course of processing these objects, other objects (handles) may 831 * have been loaded to satisfy relocation requirements. After these families 832 * have successfully loaded, they will have been propagated to the same link-map 833 * control list. The failed objects need to be removed from this list, while 834 * any successfully loaded families can be left alone, and propagated to the 835 * previous link-map control list. By associating each load request with a 836 * handle, we can isolate the failed objects while not interfering with any 837 * successfully loaded families. 838 */ 839 void 840 remove_lmc(Lm_list *lml, Rt_map *clmp, Aliste lmco, const char *name) 841 { 842 Grp_hdl *ghp; 843 Grp_desc *gdp; 844 Aliste idx; 845 Lm_cntl *lmc; 846 Rt_map *lmp; 847 848 /* 849 * Determine the link-map control list, and whether any object has been 850 * added to this list. 851 */ 852 /* LINTED */ 853 lmc = (Lm_cntl *)alist_item_by_offset(lml->lm_lists, lmco); 854 if (lmc->lc_head == NULL) 855 return; 856 857 DBG_CALL(Dbg_file_cleanup(lml, name, lmco)); 858 859 /* 860 * Obtain a handle for the first object on the link-map control list. 861 * If none exists (which would occur from a lazy load request), and 862 * the link-map control list is being relocated, create a handle. 863 */ 864 lmp = lmc->lc_head; 865 if (HANDLES(lmp)) { 866 ghp = (Grp_hdl *)HANDLES(lmp)->apl_data[0]; 867 868 } else if (lmc->lc_flags & LMC_FLG_RELOCATING) { 869 /* 870 * Establish a handle, and should anything fail, fall through 871 * to remove the link-map control list. 872 */ 873 if (((ghp = hdl_create(lml, lmc->lc_head, 0, 0, 874 GPD_ADDEPS, 0)) == NULL) || 875 (hdl_initialize(ghp, lmc->lc_head, 0, 0) == 0)) 876 lmc->lc_flags &= ~LMC_FLG_RELOCATING; 877 } else { 878 ghp = NULL; 879 } 880 881 /* 882 * If relocation hasn't begun, simply remove all the objects from this 883 * list, and any handle that may have been created. 884 */ 885 if ((lmc->lc_flags & LMC_FLG_RELOCATING) == 0) { 886 remove_incomplete(lml, lmco); 887 888 if (ghp) { 889 ghp->gh_refcnt = 1; 890 free_hdl(ghp, 0, 0); 891 } 892 return; 893 } 894 895 ASSERT(ghp != NULL); 896 897 /* 898 * As the objects of this handle are being forcibly removed, first 899 * remove any associations to objects on parent link-map control 900 * lists. This breaks the bond between a caller and a hierarchy of 901 * dependencies represented by the handle, thus the caller doesn't lock 902 * the hierarchy and prevent their deletion from the generic handle 903 * processing or remove_hdl(). 904 * 905 * This scenario can be produced when the relocation of a object 906 * results in vectoring through a filter that is already loaded. The 907 * filtee may be on the link-map list that is presently being processed, 908 * however an association between the filter and filtee would have been 909 * established during filtee processing. It is this association that 910 * must be broken to allow the objects on this link-map list to be 911 * removed. 912 */ 913 for (ALIST_TRAVERSE(ghp->gh_depends, idx, gdp)) { 914 Rt_map *lmp = gdp->gd_depend; 915 916 /* 917 * If this object has not been relocated, break down any 918 * dependency relationships the object might have established. 919 */ 920 if ((FLAGS(lmp) & FLG_RT_RELOCED) == 0) 921 remove_lists(lmp, 1); 922 923 if (CNTL(lmp) == lmco) 924 continue; 925 926 if (gdp->gd_flags & GPD_FILTER) { 927 Dyninfo *dip = DYNINFO(lmp); 928 uint_t cnt, max = DYNINFOCNT(lmp); 929 930 for (cnt = 0; cnt < max; cnt++, dip++) { 931 Alist *falp; 932 Aliste idx2; 933 Pdesc *pdp; 934 935 if (((falp = (Alist *)dip->di_info) == NULL) || 936 ((dip->di_flags & MSK_DI_FILTER) == 0)) 937 continue; 938 939 for (ALIST_TRAVERSE(falp, idx2, pdp)) { 940 if ((Grp_hdl *)pdp->pd_info == ghp) { 941 pdp->pd_info = NULL; 942 break; 943 } 944 } 945 } 946 } 947 (void) aplist_delete_value(GROUPS(lmp), ghp); 948 alist_delete(ghp->gh_depends, &idx); 949 } 950 951 /* 952 * Having removed any callers, set the group handle reference count to 953 * one, and let the generic handle remover delete the associated 954 * objects. 955 */ 956 ghp->gh_refcnt = 1; 957 (void) remove_hdl(ghp, clmp, NULL); 958 959 /* 960 * If this link-map control list still contains objects, determine the 961 * previous control list and move the objects. 962 */ 963 if (lmc->lc_head) { 964 Lm_cntl *plmc; 965 Aliste plmco; 966 967 plmco = lmco - lml->lm_lists->al_size; 968 /* LINTED */ 969 plmc = (Lm_cntl *)alist_item_by_offset(lml->lm_lists, plmco); 970 971 lm_move(lml, lmco, plmco, lmc, plmc); 972 } 973 } 974 975 /* 976 * Remove the objects associated with a handle. There are two goals here, to 977 * delete the objects associated with the handle, and to remove the handle 978 * itself. Things get a little more complex if the objects selected for 979 * deletion are filters, in this case we also need to collect their filtees, 980 * and process the combined groups as a whole. But, care still must be exer- 981 * cised to make sure any filtees found aren't being used by filters outside of 982 * the groups we've collect. The series of events is basically: 983 * 984 * o Determine the groups (handles) that might be deletable. 985 * 986 * o Determine the objects of these handles that can be deleted. 987 * 988 * o Fire the fini's of those objects selected for deletion. 989 * 990 * o Remove all inter-dependency linked lists while the objects link-maps 991 * are still available. 992 * 993 * o Remove all deletable objects link-maps and unmap the objects themselves. 994 * 995 * o Remove the handle descriptors for each deleted object, and hopefully 996 * the whole handle. 997 * 998 * An handle that can't be deleted is added to an orphans list. This list is 999 * revisited any time another dlclose() request results in handle descriptors 1000 * being deleted. These deleted descriptors can be sufficient to allow the 1001 * final deletion of the orphaned handles. 1002 */ 1003 int 1004 remove_hdl(Grp_hdl *ghp, Rt_map *clmp, int *removed) 1005 { 1006 Rt_map *lmp; 1007 int rescan = 0; 1008 int delcnt = 0, rmcnt = 0, error = 0, orphans; 1009 APlist *lmalp = NULL, *ghalp = NULL; 1010 Aliste idx1, idx2; 1011 Grp_hdl *ghp2; 1012 Grp_desc *gdp; 1013 Lm_list *lml = NULL; 1014 1015 /* 1016 * Generate the family of groups and objects that are candidates for 1017 * deletion. This consists of the objects that are explicitly defined 1018 * as dependencies of this handle, plus any filtee handles and their 1019 * associated objects. 1020 */ 1021 if (gdp_collect(&ghalp, &lmalp, ghp) == 0) { 1022 remove_collect(ghalp, lmalp); 1023 return (0); 1024 } 1025 1026 DBG_CALL(Dbg_file_hdl_title(DBG_HDL_DELETE)); 1027 1028 /* 1029 * Traverse the groups we've collected to determine if any filtees are 1030 * included. If so, and the filtee handle is in use by a filter outside 1031 * of the family of objects collected for this deletion, it can not be 1032 * removed. 1033 */ 1034 for (APLIST_TRAVERSE(ghalp, idx1, ghp2)) { 1035 Grp_hdl *ghp = ghp2; 1036 1037 DBG_CALL(Dbg_file_hdl_collect(ghp, 0)); 1038 1039 if ((ghp->gh_flags & GPH_FILTEE) == 0) 1040 continue; 1041 1042 /* 1043 * Special case for ld.so.1. There can be multiple instances of 1044 * libdl.so.1 using this handle, so although we want the handles 1045 * reference count to be decremented, we don't want the handle 1046 * removed. 1047 */ 1048 if (ghp->gh_flags & GPH_LDSO) { 1049 DBG_CALL(Dbg_file_hdl_collect(ghp, 1050 NAME(lml_rtld.lm_head))); 1051 aplist_delete(ghalp, &idx1); 1052 continue; 1053 } 1054 1055 for (ALIST_TRAVERSE(ghp->gh_depends, idx2, gdp)) { 1056 Grp_hdl *ghp3; 1057 Aliste idx3; 1058 1059 /* 1060 * Determine whether this dependency is the filtee's 1061 * parent filter, and that it isn't also an explicit 1062 * dependency (in which case it would have added its own 1063 * dependencies to the handle). 1064 */ 1065 if ((gdp->gd_flags & 1066 (GPD_FILTER | GPD_ADDEPS)) != GPD_FILTER) 1067 continue; 1068 1069 lmp = gdp->gd_depend; 1070 1071 if (FLAGS(lmp) & FLG_RT_DELETE) 1072 continue; 1073 1074 if (aplist_test(&lmalp, lmp, 0) == ALE_EXISTS) 1075 continue; 1076 1077 /* 1078 * Remove this group handle from our dynamic deletion 1079 * list. In addition, recompute the list of objects 1080 * that are candidates for deletion to continue this 1081 * group verification. 1082 */ 1083 DBG_CALL(Dbg_file_hdl_collect(ghp, NAME(lmp))); 1084 aplist_delete(ghalp, &idx1); 1085 1086 free(lmalp); 1087 lmalp = NULL; 1088 for (APLIST_TRAVERSE(ghalp, idx3, ghp3)) { 1089 Aliste idx4; 1090 Grp_desc *gdp4; 1091 1092 for (ALIST_TRAVERSE(ghp3->gh_depends, 1093 idx4, gdp4)) { 1094 if ((gdp4->gd_flags & GPD_ADDEPS) == 0) 1095 continue; 1096 if (aplist_test(&lmalp, gdp4->gd_depend, 1097 AL_CNT_GRPCLCT) == ALE_ALLOCFAIL) { 1098 remove_collect(ghalp, lmalp); 1099 return (0); 1100 } 1101 } 1102 } 1103 break; 1104 } 1105 } 1106 1107 /* 1108 * Now that we've collected all the handles dependencies, traverse the 1109 * collection determining whether they are a candidate for deletion. 1110 */ 1111 for (APLIST_TRAVERSE(lmalp, idx1, lmp)) { 1112 /* 1113 * Establish which link-map list we're dealing with for later 1114 * .fini processing. 1115 */ 1116 if (lml == NULL) 1117 lml = LIST(lmp); 1118 1119 /* 1120 * If an object isn't a candidate for deletion we'll have to 1121 * rescan the handle insuring that this objects dependencies 1122 * aren't deleted either. 1123 */ 1124 if (is_deletable(&lmalp, &ghalp, lmp)) { 1125 FLAGS(lmp) |= FLG_RT_DELETE; 1126 delcnt++; 1127 } else 1128 rescan = 1; 1129 } 1130 1131 /* 1132 * Rescan the handle if any objects where found non-deletable. 1133 */ 1134 while (rescan) 1135 rescan = remove_rescan(lmalp, ghalp, &delcnt); 1136 1137 /* 1138 * Now that we have determined the number of groups that are candidates 1139 * for removal, mark each group descriptor as a candidate for removal 1140 * from the group. 1141 */ 1142 for (APLIST_TRAVERSE(ghalp, idx1, ghp2)) { 1143 for (ALIST_TRAVERSE(ghp2->gh_depends, idx2, gdp)) 1144 gdp->gd_flags |= GPD_REMOVE; 1145 } 1146 1147 /* 1148 * Now that we know which objects on this handle can't be deleted 1149 * determine whether they still need to remain identified as belonging 1150 * to this group to be able to continue binding to one another. 1151 */ 1152 for (APLIST_TRAVERSE(ghalp, idx1, ghp2)) { 1153 Grp_hdl *ghp = ghp2; 1154 1155 for (ALIST_TRAVERSE(ghp->gh_depends, idx2, gdp)) { 1156 Aliste idx3; 1157 Bnd_desc *bdp; 1158 1159 lmp = gdp->gd_depend; 1160 1161 if (FLAGS(lmp) & FLG_RT_DELETE) 1162 continue; 1163 1164 for (APLIST_TRAVERSE(DEPENDS(lmp), idx3, bdp)) { 1165 Aliste idx4; 1166 Grp_desc *gdp4; 1167 Rt_map *dlmp = bdp->b_depend; 1168 1169 /* 1170 * If this dependency (dlmp) can be referenced 1171 * by the caller (clmp) without being part of 1172 * this group (ghp) then belonging to this group 1173 * is no longer necessary. This can occur when 1174 * objects are part of multiple handles, or if a 1175 * previously deleted handle was moved to the 1176 * orphan list and has been reopened. Note, 1177 * first make sure the caller can reference the 1178 * dependency with this group, if it can't we 1179 * must be bound to a filtee, so there's no need 1180 * to remain a part of this group either. 1181 */ 1182 if ((callable(lmp, dlmp, 0, 0) == 0) || 1183 callable(lmp, dlmp, ghp, 0)) 1184 continue; 1185 1186 if (gdp->gd_flags & GPD_REMOVE) 1187 gdp->gd_flags &= ~GPD_REMOVE; 1188 1189 for (ALIST_TRAVERSE(ghp->gh_depends, 1190 idx4, gdp4)) { 1191 if (gdp4->gd_depend != dlmp) 1192 continue; 1193 1194 if (gdp4->gd_flags & GPD_REMOVE) 1195 gdp4->gd_flags &= ~GPD_REMOVE; 1196 } 1197 } 1198 } 1199 } 1200 1201 /* 1202 * If the owner of a handle can't be deleted and it's handle descriptor 1203 * must remain also, don't delete the handle at all. Leave it for 1204 * possible later use. Although it's left intact, it will still be 1205 * moved to the orphans list, as we might be able to revisit it on later 1206 * dlclose() operations and finally remove the underlying objects. Note 1207 * that the handle still remains attached to the owner via the HANDLES 1208 * list, so that it can be re-associated to the owner if a dlopen() 1209 * of this object reoccurs. 1210 */ 1211 for (APLIST_TRAVERSE(ghalp, idx1, ghp2)) { 1212 Grp_hdl *ghp = ghp2; 1213 1214 /* 1215 * If this handle is already an orphan, or if it's owner is 1216 * deletable there's no need to inspect its dependencies. 1217 */ 1218 if ((ghp->gh_ownlmp == NULL) || 1219 (FLAGS(ghp->gh_ownlmp) & FLG_RT_DELETE)) 1220 continue; 1221 1222 /* 1223 * Make sure all handle dependencies aren't removed or the 1224 * dependencies themselves aren't deleted. 1225 */ 1226 for (ALIST_TRAVERSE(ghp->gh_depends, idx2, gdp)) { 1227 lmp = gdp->gd_depend; 1228 1229 /* 1230 * The first dependency of a non-orphaned handle is the 1231 * owner. If the handle descriptor for this isn't 1232 * required there's no need to look at any other of the 1233 * handles dependencies. 1234 */ 1235 if ((lmp == ghp->gh_ownlmp) && 1236 (gdp->gd_flags & GPD_REMOVE)) 1237 break; 1238 1239 if (gdp->gd_flags & GPD_REMOVE) 1240 gdp->gd_flags &= ~GPD_REMOVE; 1241 if (FLAGS(lmp) & FLG_RT_DELETE) { 1242 FLAGS(lmp) &= ~FLG_RT_DELETE; 1243 delcnt--; 1244 } 1245 } 1246 } 1247 1248 /* 1249 * Final scan of objects to see if any objects are to to be deleted. 1250 * Also - display diagnostic information on what operations are to be 1251 * performed on the collected handles before firing .fini's (which 1252 * produces additional diagnostics). 1253 */ 1254 for (APLIST_TRAVERSE(ghalp, idx1, ghp2)) { 1255 Grp_hdl *ghp = ghp2; 1256 1257 DBG_CALL(Dbg_file_hdl_title(DBG_HDL_DELETE)); 1258 1259 for (ALIST_TRAVERSE(ghp->gh_depends, idx2, gdp)) { 1260 int flag; 1261 1262 lmp = gdp->gd_depend; 1263 1264 /* 1265 * Note, we must never delete a parent. The parent 1266 * may already be tagged for deletion from a previous 1267 * dlclose(). That dlclose has triggered this dlclose(), 1268 * but the parents deletion is the responsibility of the 1269 * previous dlclose(), not this one. 1270 */ 1271 if ((FLAGS(lmp) & FLG_RT_DELETE) && 1272 ((gdp->gd_flags & GPD_PARENT) == 0)) { 1273 flag = DBG_DEP_DELETE; 1274 1275 /* 1276 * Remove any pathnames from the FullpathNode 1277 * AVL tree. As we're about to fire .fini's, 1278 * it's possible this object will be required 1279 * again, in which case we want to make sure a 1280 * new version of the object gets loaded. 1281 */ 1282 if (FPNODE(lmp)) 1283 fpavl_remove(lmp); 1284 } else if (gdp->gd_flags & GPD_REMOVE) 1285 flag = DBG_DEP_REMOVE; 1286 else 1287 flag = DBG_DEP_REMAIN; 1288 1289 DBG_CALL(Dbg_file_hdl_action(ghp, lmp, flag, 0)); 1290 } 1291 } 1292 1293 /* 1294 * If there are objects to be deleted process their .fini's. 1295 */ 1296 if (delcnt) { 1297 Rt_map **tobj; 1298 1299 /* 1300 * If we're being audited tell the audit library that we're 1301 * about to go deleting dependencies. 1302 */ 1303 if (clmp && ((LIST(clmp)->lm_tflags | AFLAGS(clmp)) & 1304 LML_TFLG_AUD_ACTIVITY)) 1305 audit_activity(clmp, LA_ACT_DELETE); 1306 1307 /* 1308 * Sort and fire all fini's of the objects selected for 1309 * deletion. Note that we have to start our search from the 1310 * link-map head - there's no telling whether this object has 1311 * dependencies on objects that were loaded before it and which 1312 * can now be deleted. If the tsort() fails because of an 1313 * allocation error then that might just be a symptom of why 1314 * we're here in the first place - forgo the fini's but 1315 * continue to try cleaning up. 1316 */ 1317 lml->lm_flags |= LML_FLG_OBJDELETED; 1318 1319 if (((tobj = tsort(lml->lm_head, delcnt, 1320 (RT_SORT_DELETE | RT_SORT_FWD))) != NULL) && 1321 (tobj != (Rt_map **)S_ERROR)) { 1322 error = purge_exit_handlers(lml, tobj); 1323 call_fini(lml, tobj); 1324 } 1325 1326 /* 1327 * Audit the closure of the dlopen'ed object to any local 1328 * auditors. Any global auditors would have been caught by 1329 * call_fini(), but as the link-maps CALLERS was removed 1330 * already we do the local auditors explicitly. 1331 */ 1332 for (APLIST_TRAVERSE(ghalp, idx1, ghp2)) { 1333 Grp_hdl *ghp = ghp2; 1334 Rt_map *dlmp = ghp->gh_ownlmp; 1335 1336 if (clmp && dlmp && 1337 ((LIST(dlmp)->lm_flags & LML_FLG_NOAUDIT) == 0) && 1338 (AFLAGS(clmp) & LML_TFLG_AUD_OBJCLOSE)) 1339 _audit_objclose(AUDITORS(clmp)->ad_list, dlmp); 1340 } 1341 } 1342 1343 /* 1344 * Now that .fini processing (which may have involved new bindings) 1345 * is complete, remove all inter-dependency lists from those objects 1346 * selected for deletion. 1347 */ 1348 for (APLIST_TRAVERSE(lmalp, idx1, lmp)) { 1349 Dyninfo *dip; 1350 uint_t cnt, max; 1351 1352 if (FLAGS(lmp) & FLG_RT_DELETE) 1353 remove_lists(lmp, 0); 1354 1355 /* 1356 * Determine whether we're dealing with a filter, and if so 1357 * process any inter-dependencies with its filtee's. 1358 */ 1359 if ((FLAGS1(lmp) & MSK_RT_FILTER) == 0) 1360 continue; 1361 1362 dip = DYNINFO(lmp); 1363 max = DYNINFOCNT(lmp); 1364 1365 for (cnt = 0; cnt < max; cnt++, dip++) { 1366 Alist *falp; 1367 Aliste idx2; 1368 Pdesc *pdp; 1369 1370 if (((falp = (Alist *)dip->di_info) == NULL) || 1371 ((dip->di_flags & MSK_DI_FILTER) == 0)) 1372 continue; 1373 1374 for (ALIST_TRAVERSE(falp, idx2, pdp)) { 1375 Grp_hdl *ghp; 1376 1377 if ((pdp->pd_plen == 0) || 1378 ((ghp = (Grp_hdl *)pdp->pd_info) == NULL)) 1379 continue; 1380 1381 /* 1382 * Determine whether this filtee's handle is a 1383 * part of the list of handles being deleted. 1384 */ 1385 if (aplist_test(&ghalp, ghp, 0) == ALE_EXISTS) { 1386 /* 1387 * If this handle exists on the deletion 1388 * list, then it has been removed. If 1389 * this filter isn't going to be 1390 * deleted, sever its reference to the 1391 * handle. 1392 */ 1393 pdp->pd_info = NULL; 1394 } else { 1395 /* 1396 * If this handle isn't on the deletion 1397 * list, then it must still exist. If 1398 * this filter is being deleted, make 1399 * sure the filtees reference count 1400 * gets decremented. 1401 */ 1402 if (FLAGS(lmp) & FLG_RT_DELETE) { 1403 (void) dlclose_core(ghp, 1404 lmp, lml); 1405 } 1406 } 1407 } 1408 } 1409 } 1410 1411 /* 1412 * If called from dlclose(), determine if there are already handles on 1413 * the orphans list that we can reinvestigate. 1414 */ 1415 if ((removed == 0) && aplist_nitems(hdl_alp[HDLIST_ORP])) 1416 orphans = 1; 1417 else 1418 orphans = 0; 1419 1420 /* 1421 * Finally remove any handle infrastructure and remove any objects 1422 * marked for deletion. 1423 */ 1424 for (APLIST_TRAVERSE(ghalp, idx1, ghp2)) { 1425 Grp_hdl *ghp = ghp2; 1426 1427 /* 1428 * If we're not dealing with orphaned handles remove this handle 1429 * from its present handle list. 1430 */ 1431 if (removed == 0) { 1432 uintptr_t ndx; 1433 1434 /* LINTED */ 1435 ndx = (uintptr_t)ghp % HDLIST_SZ; 1436 (void) aplist_delete_value(hdl_alp[ndx], ghp); 1437 } 1438 1439 /* 1440 * Traverse each handle dependency. Retain the dependencies 1441 * flags to insure we don't delete any parents (the flags 1442 * information is deleted as part of the alist removal that 1443 * occurs before we inspect the object for deletion). 1444 */ 1445 for (ALIST_TRAVERSE(ghp->gh_depends, idx2, gdp)) { 1446 uint_t flags = gdp->gd_flags; 1447 1448 if ((flags & GPD_REMOVE) == 0) 1449 continue; 1450 1451 lmp = gdp->gd_depend; 1452 rmcnt++; 1453 1454 /* 1455 * If this object is the owner of the handle break that 1456 * association in case the handle is retained. 1457 */ 1458 if (ghp->gh_ownlmp == lmp) { 1459 (void) aplist_delete_value(HANDLES(lmp), ghp); 1460 ghp->gh_ownlmp = NULL; 1461 } 1462 1463 (void) aplist_delete_value(GROUPS(lmp), ghp); 1464 alist_delete(ghp->gh_depends, &idx2); 1465 1466 /* 1467 * Complete the link-map deletion if appropriate. 1468 */ 1469 if ((FLAGS(lmp) & FLG_RT_DELETE) && 1470 ((flags & GPD_PARENT) == 0)) { 1471 tls_modaddrem(lmp, TM_FLG_MODREM); 1472 remove_so(LIST(lmp), lmp); 1473 } 1474 } 1475 1476 /* 1477 * If we've deleted all the dependencies of the handle, finalize 1478 * the cleanup by removing the handle itself. 1479 * 1480 * Otherwise we're left with a handle containing one or more 1481 * objects that can not be deleted (they're in use by other 1482 * handles, non-deletable, etc.), but require to remain a part 1483 * of this group to allow them to continue binding to one 1484 * another. 1485 * 1486 * If the handles reference count is zero, or represents a 1487 * link-map list (dlopen(0)), then move that handle to the 1488 * orphans list. Should another dlclose() operation occur that 1489 * results in the removal of handle descriptors, these orphan 1490 * handles are re-examined to determine if their deletion can 1491 * be completed. 1492 */ 1493 if (ghp->gh_depends->al_nitems == 0) { 1494 free(ghp->gh_depends); 1495 free(ghp); 1496 1497 } else if ((ghp->gh_refcnt == 0) && 1498 ((ghp->gh_flags & GPH_ZERO) == 0)) { 1499 /* 1500 * Move this handle to the orphans list. 1501 */ 1502 (void) aplist_append(&hdl_alp[HDLIST_ORP], ghp, 1503 AL_CNT_HANDLES); 1504 1505 if (DBG_ENABLED) { 1506 DBG_CALL(Dbg_file_hdl_title(DBG_HDL_ORPHAN)); 1507 for (ALIST_TRAVERSE(ghp->gh_depends, idx1, gdp)) 1508 DBG_CALL(Dbg_file_hdl_action(ghp, 1509 gdp->gd_depend, DBG_DEP_ORPHAN, 0)); 1510 } 1511 } 1512 } 1513 1514 /* 1515 * If no handle descriptors got removed there's no point in looking for 1516 * orphans to process. 1517 */ 1518 if (rmcnt == 0) 1519 orphans = 0; 1520 1521 /* 1522 * Cleanup any alists we've created. 1523 */ 1524 remove_collect(ghalp, lmalp); 1525 1526 /* 1527 * If orphan processing isn't required we're done. If our processing 1528 * originated from investigating orphans, return the number of handle 1529 * descriptors removed as an indication whether orphan processing 1530 * should continue. 1531 */ 1532 if (orphans == 0) { 1533 if (removed) 1534 *removed = rmcnt; 1535 return (error); 1536 } 1537 1538 /* 1539 * Traverse the orphans list as many times as necessary until no 1540 * handle removals occur. 1541 */ 1542 do { 1543 APlist *alp; 1544 Aliste idx; 1545 Grp_hdl *ghp, *oghp = NULL; 1546 int title = 0; 1547 1548 /* 1549 * Effectively clean the HDLIST_ORP list. Any object that can't 1550 * be removed will be re-added to the list. 1551 */ 1552 alp = hdl_alp[HDLIST_ORP]; 1553 hdl_alp[HDLIST_ORP] = NULL; 1554 1555 rescan = 0; 1556 for (APLIST_TRAVERSE(alp, idx, ghp)) { 1557 int _error, _remove; 1558 1559 if (title++ == 0) 1560 DBG_CALL(Dbg_file_del_rescan(ghp->gh_ownlml)); 1561 1562 if (oghp) { 1563 (void) aplist_delete_value(alp, oghp); 1564 oghp = NULL; 1565 } 1566 1567 if (((_error = remove_hdl(ghp, clmp, &_remove)) != 0) && 1568 (error == 0)) 1569 error = _error; 1570 1571 if (_remove) 1572 rescan++; 1573 1574 oghp = ghp; 1575 } 1576 if (oghp) { 1577 (void) aplist_delete_value(alp, oghp); 1578 oghp = NULL; 1579 } 1580 if (alp) 1581 free((void *)alp); 1582 1583 } while (rescan && aplist_nitems(hdl_alp[HDLIST_ORP])); 1584 1585 return (error); 1586 } 1587