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 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* 28 * Copyright (c) 1988 AT&T 29 * All Rights Reserved 30 */ 31 32 /* 33 * Object file dependent support for ELF objects. 34 */ 35 36 #include <stdio.h> 37 #include <sys/procfs.h> 38 #include <sys/mman.h> 39 #include <sys/debug.h> 40 #include <string.h> 41 #include <limits.h> 42 #include <dlfcn.h> 43 #include <debug.h> 44 #include <conv.h> 45 #include "_rtld.h" 46 #include "_audit.h" 47 #include "_elf.h" 48 #include "msg.h" 49 50 /* 51 * Default and secure dependency search paths. 52 */ 53 static Pnode elf_dflt_dirs[] = { 54 #if defined(_ELF64) 55 #ifndef SGS_PRE_UNIFIED_PROCESS 56 { MSG_ORIG(MSG_PTH_LIB_64), 0, MSG_PTH_LIB_64_SIZE, 57 LA_SER_DEFAULT, 0, &elf_dflt_dirs[1] }, 58 #endif 59 { MSG_ORIG(MSG_PTH_USRLIB_64), 0, MSG_PTH_USRLIB_64_SIZE, 60 LA_SER_DEFAULT, 0, 0 } 61 #else 62 #ifndef SGS_PRE_UNIFIED_PROCESS 63 { MSG_ORIG(MSG_PTH_LIB), 0, MSG_PTH_LIB_SIZE, 64 LA_SER_DEFAULT, 0, &elf_dflt_dirs[1] }, 65 #endif 66 { MSG_ORIG(MSG_PTH_USRLIB), 0, MSG_PTH_USRLIB_SIZE, 67 LA_SER_DEFAULT, 0, 0 } 68 #endif 69 }; 70 71 static Pnode elf_secure_dirs[] = { 72 #if defined(_ELF64) 73 #ifndef SGS_PRE_UNIFIED_PROCESS 74 { MSG_ORIG(MSG_PTH_LIBSE_64), 0, MSG_PTH_LIBSE_64_SIZE, 75 LA_SER_SECURE, 0, &elf_secure_dirs[1] }, 76 #endif 77 { MSG_ORIG(MSG_PTH_USRLIBSE_64), 0, 78 MSG_PTH_USRLIBSE_64_SIZE, 79 LA_SER_SECURE, 0, 0 } 80 #else 81 #ifndef SGS_PRE_UNIFIED_PROCESS 82 { MSG_ORIG(MSG_PTH_LIBSE), 0, MSG_PTH_LIBSE_SIZE, 83 LA_SER_SECURE, 0, &elf_secure_dirs[1] }, 84 #endif 85 { MSG_ORIG(MSG_PTH_USRLIBSE), 0, MSG_PTH_USRLIBSE_SIZE, 86 LA_SER_SECURE, 0, 0 } 87 #endif 88 }; 89 90 /* 91 * Defines for local functions. 92 */ 93 static Pnode *elf_fix_name(const char *, Rt_map *, uint_t); 94 static int elf_are_u(Rej_desc *); 95 static void elf_dladdr(ulong_t, Rt_map *, Dl_info *, void **, int); 96 static ulong_t elf_entry_pt(void); 97 static char *elf_get_so(const char *, const char *); 98 static Rt_map *elf_map_so(Lm_list *, Aliste, const char *, const char *, 99 int, int *); 100 static int elf_needed(Lm_list *, Aliste, Rt_map *, int *); 101 static void elf_unmap_so(Rt_map *); 102 static int elf_verify_vers(const char *, Rt_map *, Rt_map *); 103 104 /* 105 * Functions and data accessed through indirect pointers. 106 */ 107 Fct elf_fct = { 108 elf_are_u, 109 elf_entry_pt, 110 elf_map_so, 111 elf_unmap_so, 112 elf_needed, 113 lookup_sym, 114 elf_reloc, 115 elf_dflt_dirs, 116 elf_secure_dirs, 117 elf_fix_name, 118 elf_get_so, 119 elf_dladdr, 120 dlsym_handle, 121 elf_verify_vers, 122 elf_set_prot 123 }; 124 125 126 /* 127 * Redefine NEEDED name if necessary. 128 */ 129 static Pnode * 130 elf_fix_name(const char *name, Rt_map *clmp, uint_t orig) 131 { 132 /* 133 * For ABI compliance, if we are asked for ld.so.1, then really give 134 * them libsys.so.1 (the SONAME of libsys.so.1 is ld.so.1). 135 */ 136 if (((*name == '/') && 137 /* BEGIN CSTYLED */ 138 #if defined(_ELF64) 139 (strcmp(name, MSG_ORIG(MSG_PTH_RTLD_64)) == 0)) || 140 #else 141 (strcmp(name, MSG_ORIG(MSG_PTH_RTLD)) == 0)) || 142 #endif 143 (strcmp(name, MSG_ORIG(MSG_FIL_RTLD)) == 0)) { 144 /* END CSTYLED */ 145 Pnode *pnp; 146 147 DBG_CALL(Dbg_file_fixname(LIST(clmp), name, 148 MSG_ORIG(MSG_PTH_LIBSYS))); 149 if (((pnp = calloc(sizeof (Pnode), 1)) == 0) || 150 ((pnp->p_name = strdup(MSG_ORIG(MSG_PTH_LIBSYS))) == 0)) { 151 if (pnp) 152 free(pnp); 153 return (0); 154 } 155 pnp->p_len = MSG_PTH_LIBSYS_SIZE; 156 return (pnp); 157 } 158 159 return (expand_paths(clmp, name, orig, 0)); 160 } 161 162 /* 163 * Determine if we have been given an ELF file and if so determine if the file 164 * is compatible. Returns 1 if true, else 0 and sets the reject descriptor 165 * with associated error information. 166 */ 167 static int 168 elf_are_u(Rej_desc *rej) 169 { 170 Ehdr *ehdr; 171 172 /* 173 * Determine if we're an elf file. If not simply return, we don't set 174 * any rejection information as this test allows use to scroll through 175 * the objects we support (ELF, AOUT). 176 */ 177 if (fmap->fm_fsize < sizeof (Ehdr) || 178 fmap->fm_maddr[EI_MAG0] != ELFMAG0 || 179 fmap->fm_maddr[EI_MAG1] != ELFMAG1 || 180 fmap->fm_maddr[EI_MAG2] != ELFMAG2 || 181 fmap->fm_maddr[EI_MAG3] != ELFMAG3) { 182 return (0); 183 } 184 185 /* 186 * Check class and encoding. 187 */ 188 /* LINTED */ 189 ehdr = (Ehdr *)fmap->fm_maddr; 190 if (ehdr->e_ident[EI_CLASS] != M_CLASS) { 191 rej->rej_type = SGS_REJ_CLASS; 192 rej->rej_info = (uint_t)ehdr->e_ident[EI_CLASS]; 193 return (0); 194 } 195 if (ehdr->e_ident[EI_DATA] != M_DATA) { 196 rej->rej_type = SGS_REJ_DATA; 197 rej->rej_info = (uint_t)ehdr->e_ident[EI_DATA]; 198 return (0); 199 } 200 if ((ehdr->e_type != ET_REL) && (ehdr->e_type != ET_EXEC) && 201 (ehdr->e_type != ET_DYN)) { 202 rej->rej_type = SGS_REJ_TYPE; 203 rej->rej_info = (uint_t)ehdr->e_type; 204 return (0); 205 } 206 207 /* 208 * Verify machine specific flags, and hardware capability requirements. 209 */ 210 if ((elf_mach_flags_check(rej, ehdr) == 0) || 211 (cap_check(rej, ehdr) == 0)) 212 return (0); 213 214 /* 215 * Verify ELF version. ??? is this too restrictive ??? 216 */ 217 if (ehdr->e_version > EV_CURRENT) { 218 rej->rej_type = SGS_REJ_VERSION; 219 rej->rej_info = (uint_t)ehdr->e_version; 220 return (0); 221 } 222 return (1); 223 } 224 225 /* 226 * The runtime linker employs lazy loading to provide the libraries needed for 227 * debugging, preloading .o's and dldump(). As these are seldom used, the 228 * standard startup of ld.so.1 doesn't initialize all the information necessary 229 * to perform plt relocation on ld.so.1's link-map. The first time lazy loading 230 * is called we get here to perform these initializations: 231 * 232 * o elf_needed() is called to set up the DYNINFO() indexes for each lazy 233 * dependency. Typically, for all other objects, this is called during 234 * analyze_so(), but as ld.so.1 is set-contained we skip this processing. 235 * 236 * o For intel, ld.so.1's JMPSLOT relocations need relative updates. These 237 * are by default skipped thus delaying all relative relocation processing 238 * on every invocation of ld.so.1. 239 */ 240 int 241 elf_rtld_load() 242 { 243 Lm_list *lml = &lml_rtld; 244 Rt_map *lmp = lml->lm_head; 245 246 if (lml->lm_flags & LML_FLG_PLTREL) 247 return (1); 248 249 /* 250 * As we need to refer to the DYNINFO() information, insure that it has 251 * been initialized. 252 */ 253 if (elf_needed(lml, ALIST_OFF_DATA, lmp, NULL) == 0) 254 return (0); 255 256 #if defined(__i386) 257 /* 258 * This is a kludge to give ld.so.1 a performance benefit on i386. 259 * It's based around two factors. 260 * 261 * o JMPSLOT relocations (PLT's) actually need a relative relocation 262 * applied to the GOT entry so that they can find PLT0. 263 * 264 * o ld.so.1 does not exercise *any* PLT's before it has made a call 265 * to elf_lazy_load(). This is because all dynamic dependencies 266 * are recorded as lazy dependencies. 267 */ 268 (void) elf_reloc_relacount((ulong_t)JMPREL(lmp), 269 (ulong_t)(PLTRELSZ(lmp) / RELENT(lmp)), (ulong_t)RELENT(lmp), 270 (ulong_t)ADDR(lmp)); 271 #endif 272 273 lml->lm_flags |= LML_FLG_PLTREL; 274 return (1); 275 } 276 277 /* 278 * Lazy load an object. 279 */ 280 Rt_map * 281 elf_lazy_load(Rt_map *clmp, Slookup *slp, uint_t ndx, const char *sym, 282 int *in_nfavl) 283 { 284 Rt_map *nlmp, *hlmp; 285 Dyninfo *dip = &DYNINFO(clmp)[ndx], *pdip; 286 uint_t flags = 0; 287 Pnode *pnp; 288 const char *name; 289 Lm_list *lml = LIST(clmp); 290 Lm_cntl *lmc; 291 Aliste lmco; 292 293 /* 294 * If this dependency has already been processed, we're done. 295 */ 296 if (((nlmp = (Rt_map *)dip->di_info) != 0) || 297 (dip->di_flags & FLG_DI_LDD_DONE)) 298 return (nlmp); 299 300 /* 301 * If we're running under ldd(1), indicate that this dependency has been 302 * processed (see test above). It doesn't matter whether the object is 303 * successfully loaded or not, this flag simply ensures that we don't 304 * repeatedly attempt to load an object that has already failed to load. 305 * To do so would create multiple failure diagnostics for the same 306 * object under ldd(1). 307 */ 308 if (lml->lm_flags & LML_FLG_TRC_ENABLE) 309 dip->di_flags |= FLG_DI_LDD_DONE; 310 311 /* 312 * Determine the initial dependency name. 313 */ 314 name = STRTAB(clmp) + DYN(clmp)[ndx].d_un.d_val; 315 DBG_CALL(Dbg_file_lazyload(clmp, name, sym)); 316 317 /* 318 * If this object needs to establish its own group, make sure a handle 319 * is created. 320 */ 321 if (dip->di_flags & FLG_DI_GROUP) 322 flags |= (FLG_RT_SETGROUP | FLG_RT_HANDLE); 323 324 /* 325 * Lazy dependencies are identified as DT_NEEDED entries with a 326 * DF_P1_LAZYLOAD flag in the previous DT_POSFLAG_1 element. The 327 * dynamic information element that corresponds to the DT_POSFLAG_1 328 * entry is free, and thus used to store the present entrance 329 * identifier. This identifier is used to prevent multiple attempts to 330 * load a failed lazy loadable dependency within the same runtime linker 331 * operation. However, future attempts to reload this dependency are 332 * still possible. 333 */ 334 if (ndx && (pdip = dip - 1) && (pdip->di_flags & FLG_DI_POSFLAG1)) 335 pdip->di_info = (void *)slp->sl_id; 336 337 /* 338 * Expand the requested name if necessary. 339 */ 340 if ((pnp = elf_fix_name(name, clmp, 0)) == 0) 341 return (0); 342 343 /* 344 * Provided the object on the head of the link-map has completed its 345 * relocation, create a new link-map control list for this request. 346 */ 347 hlmp = lml->lm_head; 348 if (FLAGS(hlmp) & FLG_RT_RELOCED) { 349 if ((lmc = alist_append(&lml->lm_lists, 0, sizeof (Lm_cntl), 350 AL_CNT_LMLISTS)) == 0) { 351 remove_pnode(pnp); 352 return (0); 353 } 354 lmco = (Aliste)((char *)lmc - (char *)lml->lm_lists); 355 } else { 356 lmc = 0; 357 lmco = ALIST_OFF_DATA; 358 } 359 360 /* 361 * Load the associated object. 362 */ 363 dip->di_info = nlmp = 364 load_one(lml, lmco, pnp, clmp, MODE(clmp), flags, 0, in_nfavl); 365 366 /* 367 * Remove any expanded pathname infrastructure. Reduce the pending lazy 368 * dependency count of the caller, together with the link-map lists 369 * count of objects that still have lazy dependencies pending. 370 */ 371 remove_pnode(pnp); 372 if (--LAZY(clmp) == 0) 373 LIST(clmp)->lm_lazy--; 374 375 /* 376 * Finish processing the objects associated with this request, and 377 * create an association between the caller and this dependency. 378 */ 379 if (nlmp && ((bind_one(clmp, nlmp, BND_NEEDED) == 0) || 380 (analyze_lmc(lml, lmco, nlmp, in_nfavl) == 0) || 381 (relocate_lmc(lml, lmco, clmp, nlmp, in_nfavl) == 0))) 382 dip->di_info = nlmp = 0; 383 384 /* 385 * If this lazyload has failed, and we've created a new link-map 386 * control list to which this request has added objects, then remove 387 * all the objects that have been associated to this request. 388 */ 389 if ((nlmp == 0) && lmc && lmc->lc_head) 390 remove_lmc(lml, clmp, lmc, lmco, name); 391 392 /* 393 * Finally, remove any link-map control list that was created. 394 */ 395 if (lmc) 396 remove_cntl(lml, lmco); 397 398 /* 399 * If this lazy loading failed, record the fact, and bump the lazy 400 * counts. 401 */ 402 if (nlmp == 0) { 403 dip->di_flags |= FLG_DI_LAZYFAIL; 404 if (LAZY(clmp)++ == 0) 405 LIST(clmp)->lm_lazy++; 406 } 407 408 return (nlmp); 409 } 410 411 /* 412 * Return the entry point of the ELF executable. 413 */ 414 static ulong_t 415 elf_entry_pt(void) 416 { 417 return (ENTRY(lml_main.lm_head)); 418 } 419 420 /* 421 * Unmap a given ELF shared object from the address space. 422 */ 423 static void 424 elf_unmap_so(Rt_map *lmp) 425 { 426 caddr_t addr; 427 size_t size; 428 Mmap *mmaps; 429 430 /* 431 * If this link map represents a relocatable object concatenation, then 432 * the image was simply generated in allocated memory. Free the memory. 433 * 434 * Note: the memory was originally allocated in the libelf:_elf_outmap 435 * routine and would normally have been free'd in elf_outsync(), but 436 * because we 'interpose' on that routine the memory wasn't free'd at 437 * that time. 438 */ 439 if (FLAGS(lmp) & FLG_RT_IMGALLOC) { 440 free((void *)ADDR(lmp)); 441 return; 442 } 443 444 /* 445 * If padding was enabled via rtld_db, then we have at least one page 446 * in front of the image - and possibly a trailing page. 447 * Unmap the front page first: 448 */ 449 if (PADSTART(lmp) != ADDR(lmp)) { 450 addr = (caddr_t)M_PTRUNC(PADSTART(lmp)); 451 size = ADDR(lmp) - (ulong_t)addr; 452 (void) munmap(addr, size); 453 } 454 455 /* 456 * Unmap any trailing padding. 457 */ 458 if (M_PROUND((PADSTART(lmp) + PADIMLEN(lmp))) > 459 M_PROUND(ADDR(lmp) + MSIZE(lmp))) { 460 addr = (caddr_t)M_PROUND(ADDR(lmp) + MSIZE(lmp)); 461 size = M_PROUND(PADSTART(lmp) + PADIMLEN(lmp)) - (ulong_t)addr; 462 (void) munmap(addr, size); 463 } 464 465 /* 466 * Unmmap all mapped segments. 467 */ 468 for (mmaps = MMAPS(lmp); mmaps->m_vaddr; mmaps++) 469 (void) munmap(mmaps->m_vaddr, mmaps->m_msize); 470 } 471 472 /* 473 * Determine if a dependency requires a particular version and if so verify 474 * that the version exists in the dependency. 475 */ 476 static int 477 elf_verify_vers(const char *name, Rt_map *clmp, Rt_map *nlmp) 478 { 479 Verneed *vnd = VERNEED(clmp); 480 int _num, num = VERNEEDNUM(clmp); 481 char *cstrs = (char *)STRTAB(clmp); 482 Lm_list *lml = LIST(clmp); 483 484 /* 485 * Traverse the callers version needed information and determine if any 486 * specific versions are required from the dependency. 487 */ 488 DBG_CALL(Dbg_ver_need_title(LIST(clmp), NAME(clmp))); 489 for (_num = 1; _num <= num; _num++, 490 vnd = (Verneed *)((Xword)vnd + vnd->vn_next)) { 491 Half cnt = vnd->vn_cnt; 492 Vernaux *vnap; 493 char *nstrs, *need; 494 495 /* 496 * Determine if a needed entry matches this dependency. 497 */ 498 need = (char *)(cstrs + vnd->vn_file); 499 if (strcmp(name, need) != 0) 500 continue; 501 502 if ((lml->lm_flags & LML_FLG_TRC_VERBOSE) && 503 ((FLAGS1(clmp) & FL1_RT_LDDSTUB) == 0)) 504 (void) printf(MSG_INTL(MSG_LDD_VER_FIND), name); 505 506 /* 507 * Validate that each version required actually exists in the 508 * dependency. 509 */ 510 nstrs = (char *)STRTAB(nlmp); 511 512 for (vnap = (Vernaux *)((Xword)vnd + vnd->vn_aux); cnt; 513 cnt--, vnap = (Vernaux *)((Xword)vnap + vnap->vna_next)) { 514 char *version, *define; 515 Verdef *vdf = VERDEF(nlmp); 516 ulong_t _num, num = VERDEFNUM(nlmp); 517 int found = 0; 518 519 /* 520 * Skip validation of versions that are marked 521 * INFO. This optimization is used for versions 522 * that are inherited by another version. Verification 523 * of the inheriting version is sufficient. 524 * 525 * Such versions are recorded in the object for the 526 * benefit of VERSYM entries that refer to them. This 527 * provides a purely diagnositic benefit. 528 */ 529 if (vnap->vna_flags & VER_FLG_INFO) 530 continue; 531 532 version = (char *)(cstrs + vnap->vna_name); 533 DBG_CALL(Dbg_ver_need_entry(lml, 0, need, version)); 534 535 for (_num = 1; _num <= num; _num++, 536 vdf = (Verdef *)((Xword)vdf + vdf->vd_next)) { 537 Verdaux *vdap; 538 539 if (vnap->vna_hash != vdf->vd_hash) 540 continue; 541 542 vdap = (Verdaux *)((Xword)vdf + vdf->vd_aux); 543 define = (char *)(nstrs + vdap->vda_name); 544 if (strcmp(version, define) != 0) 545 continue; 546 547 found++; 548 break; 549 } 550 551 /* 552 * If we're being traced print out any matched version 553 * when the verbose (-v) option is in effect. Always 554 * print any unmatched versions. 555 */ 556 if (lml->lm_flags & LML_FLG_TRC_ENABLE) { 557 /* BEGIN CSTYLED */ 558 if (found) { 559 if (!(lml->lm_flags & LML_FLG_TRC_VERBOSE)) 560 continue; 561 562 (void) printf(MSG_ORIG(MSG_LDD_VER_FOUND), 563 need, version, NAME(nlmp)); 564 } else { 565 if (rtld_flags & RT_FL_SILENCERR) 566 continue; 567 568 (void) printf(MSG_INTL(MSG_LDD_VER_NFOUND), 569 need, version); 570 } 571 /* END CSTYLED */ 572 continue; 573 } 574 575 /* 576 * If the version hasn't been found then this is a 577 * candidate for a fatal error condition. Weak 578 * version definition requirements are silently 579 * ignored. Also, if the image inspected for a version 580 * definition has no versioning recorded at all then 581 * silently ignore this (this provides better backward 582 * compatibility to old images created prior to 583 * versioning being available). Both of these skipped 584 * diagnostics are available under tracing (see above). 585 */ 586 if ((found == 0) && (num != 0) && 587 (!(vnap->vna_flags & VER_FLG_WEAK))) { 588 eprintf(lml, ERR_FATAL, 589 MSG_INTL(MSG_VER_NFOUND), need, version, 590 NAME(clmp)); 591 return (0); 592 } 593 } 594 } 595 DBG_CALL(Dbg_util_nl(lml, DBG_NL_STD)); 596 return (1); 597 } 598 599 /* 600 * Search through the dynamic section for DT_NEEDED entries and perform one 601 * of two functions. If only the first argument is specified then load the 602 * defined shared object, otherwise add the link map representing the defined 603 * link map the the dlopen list. 604 */ 605 static int 606 elf_needed(Lm_list *lml, Aliste lmco, Rt_map *clmp, int *in_nfavl) 607 { 608 Dyn *dyn, *pdyn; 609 ulong_t ndx = 0; 610 uint_t lazy, flags; 611 Word lmflags = lml->lm_flags; 612 Word lmtflags = lml->lm_tflags; 613 614 /* 615 * Process each shared object on needed list. 616 */ 617 if (DYN(clmp) == 0) 618 return (1); 619 620 for (dyn = (Dyn *)DYN(clmp), pdyn = NULL; dyn->d_tag != DT_NULL; 621 pdyn = dyn++, ndx++) { 622 Dyninfo *dip = &DYNINFO(clmp)[ndx]; 623 Rt_map *nlmp = 0; 624 char *name; 625 int silent = 0; 626 Pnode *pnp; 627 628 switch (dyn->d_tag) { 629 case DT_POSFLAG_1: 630 dip->di_flags |= FLG_DI_POSFLAG1; 631 continue; 632 case DT_NEEDED: 633 case DT_USED: 634 lazy = flags = 0; 635 dip->di_flags |= FLG_DI_NEEDED; 636 637 if (pdyn && (pdyn->d_tag == DT_POSFLAG_1)) { 638 if ((pdyn->d_un.d_val & DF_P1_LAZYLOAD) && 639 ((lmtflags & LML_TFLG_NOLAZYLD) == 0)) { 640 dip->di_flags |= FLG_DI_LAZY; 641 lazy = 1; 642 } 643 if (pdyn->d_un.d_val & DF_P1_GROUPPERM) { 644 dip->di_flags |= FLG_DI_GROUP; 645 flags = 646 (FLG_RT_SETGROUP | FLG_RT_HANDLE); 647 } 648 } 649 650 name = (char *)STRTAB(clmp) + dyn->d_un.d_val; 651 652 /* 653 * NOTE, libc.so.1 can't be lazy loaded. Although a 654 * lazy position flag won't be produced when a RTLDINFO 655 * .dynamic entry is found (introduced with the UPM in 656 * Solaris 10), it was possible to mark libc for lazy 657 * loading on previous releases. To reduce the overhead 658 * of testing for this occurrence, only carry out this 659 * check for the first object on the link-map list 660 * (there aren't many applications built without libc). 661 */ 662 if (lazy && (lml->lm_head == clmp) && 663 (strcmp(name, MSG_ORIG(MSG_FIL_LIBC)) == 0)) 664 lazy = 0; 665 666 /* 667 * Don't bring in lazy loaded objects yet unless we've 668 * been asked to attempt to load all available objects 669 * (crle(1) sets LD_FLAGS=loadavail). Even under 670 * RTLD_NOW we don't process this - RTLD_NOW will cause 671 * relocation processing which in turn might trigger 672 * lazy loading, but its possible that the object has a 673 * lazy loaded file with no bindings (i.e., it should 674 * never have been a dependency in the first place). 675 */ 676 if (lazy) { 677 if ((lmflags & LML_FLG_LOADAVAIL) == 0) { 678 LAZY(clmp)++; 679 lazy = flags = 0; 680 continue; 681 } 682 683 /* 684 * Silence any error messages - see description 685 * under elf_lookup_filtee(). 686 */ 687 if ((rtld_flags & RT_FL_SILENCERR) == 0) { 688 rtld_flags |= RT_FL_SILENCERR; 689 silent = 1; 690 } 691 } 692 break; 693 case DT_AUXILIARY: 694 dip->di_flags |= FLG_DI_AUXFLTR; 695 continue; 696 case DT_SUNW_AUXILIARY: 697 dip->di_flags |= (FLG_DI_AUXFLTR | FLG_DI_SYMFLTR); 698 continue; 699 case DT_FILTER: 700 dip->di_flags |= FLG_DI_STDFLTR; 701 continue; 702 case DT_SUNW_FILTER: 703 dip->di_flags |= (FLG_DI_STDFLTR | FLG_DI_SYMFLTR); 704 continue; 705 default: 706 continue; 707 } 708 709 DBG_CALL(Dbg_file_needed(clmp, name)); 710 711 /* 712 * If we're running under ldd(1), indicate that this dependency 713 * has been processed. It doesn't matter whether the object is 714 * successfully loaded or not, this flag simply ensures that we 715 * don't repeatedly attempt to load an object that has already 716 * failed to load. To do so would create multiple failure 717 * diagnostics for the same object under ldd(1). 718 */ 719 if (lml->lm_flags & LML_FLG_TRC_ENABLE) 720 dip->di_flags |= FLG_DI_LDD_DONE; 721 722 /* 723 * Establish the objects name, load it and establish a binding 724 * with the caller. 725 */ 726 if (((pnp = elf_fix_name(name, clmp, 0)) == 0) || ((nlmp = 727 load_one(lml, lmco, pnp, clmp, MODE(clmp), flags, 0, 728 in_nfavl)) == 0) || (bind_one(clmp, nlmp, BND_NEEDED) == 0)) 729 nlmp = 0; 730 731 /* 732 * Clean up any infrastructure, including the removal of the 733 * error suppression state, if it had been previously set in 734 * this routine. 735 */ 736 if (pnp) 737 remove_pnode(pnp); 738 if (silent) 739 rtld_flags &= ~RT_FL_SILENCERR; 740 741 if ((dip->di_info = (void *)nlmp) == 0) { 742 /* 743 * If the object could not be mapped, continue if error 744 * suppression is established or we're here with ldd(1). 745 */ 746 if ((MODE(clmp) & RTLD_CONFGEN) || (lmflags & 747 (LML_FLG_LOADAVAIL | LML_FLG_TRC_ENABLE))) 748 continue; 749 else 750 return (0); 751 } 752 } 753 754 if (LAZY(clmp)) 755 lml->lm_lazy++; 756 757 return (1); 758 } 759 760 static int 761 elf_map_check(Lm_list *lml, const char *name, caddr_t vaddr, Off size) 762 { 763 prmap_t *maps, *_maps; 764 int pfd, num, _num; 765 caddr_t eaddr = vaddr + size; 766 int err; 767 768 /* 769 * If memory reservations have been established for alternative objects 770 * determine if this object falls within the reservation, if it does no 771 * further checking is required. 772 */ 773 if (rtld_flags & RT_FL_MEMRESV) { 774 Rtc_head *head = (Rtc_head *)config->c_bgn; 775 776 if ((vaddr >= (caddr_t)(uintptr_t)head->ch_resbgn) && 777 (eaddr <= (caddr_t)(uintptr_t)head->ch_resend)) 778 return (0); 779 } 780 781 /* 782 * Determine the mappings presently in use by this process. 783 */ 784 if ((pfd = pr_open(lml)) == FD_UNAVAIL) 785 return (1); 786 787 if (ioctl(pfd, PIOCNMAP, (void *)&num) == -1) { 788 err = errno; 789 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_SYS_PROC), name, 790 strerror(err)); 791 return (1); 792 } 793 794 if ((maps = malloc((num + 1) * sizeof (prmap_t))) == 0) 795 return (1); 796 797 if (ioctl(pfd, PIOCMAP, (void *)maps) == -1) { 798 err = errno; 799 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_SYS_PROC), name, 800 strerror(err)); 801 free(maps); 802 return (1); 803 } 804 805 /* 806 * Determine if the supplied address clashes with any of the present 807 * process mappings. 808 */ 809 for (_num = 0, _maps = maps; _num < num; _num++, _maps++) { 810 caddr_t _eaddr = _maps->pr_vaddr + _maps->pr_size; 811 Rt_map *lmp; 812 const char *str; 813 814 if ((eaddr < _maps->pr_vaddr) || (vaddr >= _eaddr)) 815 continue; 816 817 /* 818 * We have a memory clash. See if one of the known dynamic 819 * dependency mappings represents this space so as to provide 820 * the user a more meaningful message. 821 */ 822 if ((lmp = _caller(vaddr, 0)) != 0) 823 str = NAME(lmp); 824 else 825 str = MSG_INTL(MSG_STR_UNKNOWN); 826 827 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_GEN_MAPINUSE), name, 828 EC_NATPTR(vaddr), EC_OFF(size), str); 829 return (1); 830 } 831 free(maps); 832 return (0); 833 } 834 835 /* 836 * Obtain a memory reservation. On newer systems, both MAP_ANON and MAP_ALIGN 837 * are used to obtained an aligned reservation from anonymous memory. If 838 * MAP_ANON isn't available, then MAP_ALIGN isn't either, so obtain a standard 839 * reservation using the file as backing. 840 */ 841 static Am_ret 842 elf_map_reserve(Lm_list *lml, const char *name, caddr_t *maddr, Off msize, 843 int mperm, int fd, Xword align) 844 { 845 Am_ret amret; 846 int mflag = MAP_PRIVATE | MAP_NORESERVE; 847 848 #if defined(MAP_ALIGN) 849 if ((rtld_flags2 & RT_FL2_NOMALIGN) == 0) { 850 mflag |= MAP_ALIGN; 851 *maddr = (caddr_t)align; 852 } 853 #endif 854 if ((amret = anon_map(lml, maddr, msize, PROT_NONE, mflag)) == AM_ERROR) 855 return (amret); 856 857 if (amret == AM_OK) 858 return (AM_OK); 859 860 /* 861 * If an anonymous memory request failed (which should only be the 862 * case if it is unsupported on the system we're running on), establish 863 * the initial mapping directly from the file. 864 */ 865 *maddr = 0; 866 if ((*maddr = mmap(*maddr, msize, mperm, MAP_PRIVATE, 867 fd, 0)) == MAP_FAILED) { 868 int err = errno; 869 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_SYS_MMAP), name, 870 strerror(err)); 871 return (AM_ERROR); 872 } 873 return (AM_NOSUP); 874 } 875 876 static void * 877 elf_map_textdata(caddr_t addr, Off flen, int mperm, int phdr_mperm, int mflag, 878 int fd, Off foff) 879 { 880 #if defined(MAP_TEXT) && defined(MAP_INITDATA) 881 static int notd = 0; 882 883 /* 884 * If MAP_TEXT and MAP_INITDATA are available, select the appropriate 885 * flag. 886 */ 887 if (notd == 0) { 888 if ((phdr_mperm & (PROT_WRITE | PROT_EXEC)) == PROT_EXEC) 889 mflag |= MAP_TEXT; 890 else 891 mflag |= MAP_INITDATA; 892 } 893 #endif 894 if (mmap((caddr_t)addr, flen, mperm, mflag, fd, foff) != MAP_FAILED) 895 return (0); 896 897 #if defined(MAP_TEXT) && defined(MAP_INITDATA) 898 if ((notd == 0) && (errno == EINVAL)) { 899 /* 900 * MAP_TEXT and MAP_INITDATA may not be supported on this 901 * platform, try again without. 902 */ 903 notd = 1; 904 mflag &= ~(MAP_TEXT | MAP_INITDATA); 905 906 return (mmap((caddr_t)addr, flen, mperm, mflag, fd, foff)); 907 } 908 #endif 909 return (MAP_FAILED); 910 } 911 912 /* 913 * Map in a file. 914 */ 915 static caddr_t 916 elf_map_it( 917 Lm_list *lml, /* link-map list */ 918 const char *name, /* actual name stored for pathname */ 919 Off fsize, /* total mapping claim of the file */ 920 Ehdr *ehdr, /* ELF header of file */ 921 Phdr *fphdr, /* first loadable Phdr */ 922 Phdr *lphdr, /* last loadable Phdr */ 923 Phdr **rrphdr, /* return first Phdr in reservation */ 924 caddr_t *rraddr, /* return start of reservation */ 925 Off *rrsize, /* return total size of reservation */ 926 int fixed, /* image is resolved to a fixed addr */ 927 int fd, /* images file descriptor */ 928 Xword align, /* image segments maximum alignment */ 929 Mmap *mmaps, /* mmap information array and */ 930 uint_t *mmapcnt) /* mapping count */ 931 { 932 caddr_t raddr; /* reservation address */ 933 Off rsize; /* reservation size */ 934 Phdr *phdr; /* working program header poiner */ 935 caddr_t maddr; /* working mmap address */ 936 caddr_t faddr; /* working file address */ 937 size_t padsize; /* object padding requirement */ 938 size_t padpsize = 0; /* padding size rounded to next page */ 939 size_t padmsize = 0; /* padding size rounded for alignment */ 940 int skipfseg; /* skip mapping first segment */ 941 int mperm; /* segment permissions */ 942 Am_ret amret = AM_NOSUP; 943 944 /* 945 * If padding is required extend both the front and rear of the image. 946 * To insure the image itself is mapped at the correct alignment the 947 * initial padding is rounded up to the nearest page. Once the image is 948 * mapped the excess can be pruned to the nearest page required for the 949 * actual padding itself. 950 */ 951 if ((padsize = r_debug.rtd_objpad) != 0) { 952 padpsize = M_PROUND(padsize); 953 if (fixed) 954 padmsize = padpsize; 955 else 956 padmsize = S_ROUND(padsize, align); 957 } 958 959 /* 960 * Determine the initial permissions used to map in the first segment. 961 * If this segments memsz is greater that its filesz then the difference 962 * must be zeroed. Make sure this segment is writable. 963 */ 964 mperm = 0; 965 if (fphdr->p_flags & PF_R) 966 mperm |= PROT_READ; 967 if (fphdr->p_flags & PF_X) 968 mperm |= PROT_EXEC; 969 if ((fphdr->p_flags & PF_W) || (fphdr->p_memsz > fphdr->p_filesz)) 970 mperm |= PROT_WRITE; 971 972 /* 973 * Determine whether or not to let system reserve address space based on 974 * whether this is a dynamic executable (addresses in object are fixed) 975 * or a shared object (addresses in object are relative to the objects' 976 * base). 977 */ 978 if (fixed) { 979 /* 980 * Determine the reservation address and size, and insure that 981 * this reservation isn't already in use. 982 */ 983 faddr = maddr = (caddr_t)M_PTRUNC((ulong_t)fphdr->p_vaddr); 984 raddr = maddr - padpsize; 985 rsize = fsize + padpsize + padsize; 986 987 if (lml_main.lm_head) { 988 if (elf_map_check(lml, name, raddr, rsize) != 0) 989 return (0); 990 } 991 992 /* 993 * As this is a fixed image, all segments must be individually 994 * mapped. 995 */ 996 skipfseg = 0; 997 998 } else { 999 size_t esize; 1000 1001 /* 1002 * If this isn't a fixed image, reserve enough address space for 1003 * the entire image to be mapped. The amount of reservation is 1004 * the range between the beginning of the first, and end of the 1005 * last loadable segment, together with any padding, plus the 1006 * alignment of the first segment. 1007 * 1008 * The optimal reservation is made as a no-reserve mapping from 1009 * anonymous memory. Each segment is then mapped into this 1010 * reservation. If the anonymous mapping capability isn't 1011 * available, the reservation is obtained from the file itself. 1012 * In this case the first segment of the image is mapped as part 1013 * of the reservation, thus only the following segments need to 1014 * be remapped. 1015 */ 1016 rsize = fsize + padmsize + padsize; 1017 if ((amret = elf_map_reserve(lml, name, &raddr, rsize, mperm, 1018 fd, align)) == AM_ERROR) 1019 return (0); 1020 maddr = raddr + padmsize; 1021 faddr = (caddr_t)S_ROUND((Off)maddr, align); 1022 1023 /* 1024 * If this reservation has been obtained from anonymous memory, 1025 * then all segments must be individually mapped. Otherwise, 1026 * the first segment heads the reservation. 1027 */ 1028 if (amret == AM_OK) 1029 skipfseg = 0; 1030 else 1031 skipfseg = 1; 1032 1033 /* 1034 * For backward compatibility (where MAP_ALIGN isn't available), 1035 * insure the alignment of the reservation is adequate for this 1036 * object, and if not remap the object to obtain the correct 1037 * alignment. 1038 */ 1039 if (faddr != maddr) { 1040 (void) munmap(raddr, rsize); 1041 1042 rsize += align; 1043 if ((amret = elf_map_reserve(lml, name, &raddr, rsize, 1044 mperm, fd, align)) == AM_ERROR) 1045 return (0); 1046 1047 maddr = faddr = (caddr_t)S_ROUND((Off)(raddr + 1048 padpsize), align); 1049 1050 esize = maddr - raddr + padpsize; 1051 1052 /* 1053 * As ths image has been realigned, the first segment 1054 * of the file needs to be remapped to its correct 1055 * location. 1056 */ 1057 skipfseg = 0; 1058 } else 1059 esize = padmsize - padpsize; 1060 1061 /* 1062 * If this reservation included padding, remove any excess for 1063 * the start of the image (the padding was adjusted to insure 1064 * the image was aligned appropriately). 1065 */ 1066 if (esize) { 1067 (void) munmap(raddr, esize); 1068 raddr += esize; 1069 rsize -= esize; 1070 } 1071 } 1072 1073 /* 1074 * At this point we know the initial location of the image, and its 1075 * size. Pass these back to the caller for inclusion in the link-map 1076 * that will eventually be created. 1077 */ 1078 *rraddr = raddr; 1079 *rrsize = rsize; 1080 1081 /* 1082 * The first loadable segment is now pointed to by maddr. This segment 1083 * will eventually contain the elf header and program headers, so reset 1084 * the program header. Pass this back to the caller for inclusion in 1085 * the link-map so it can be used for later unmapping operations. 1086 */ 1087 /* LINTED */ 1088 *rrphdr = (Phdr *)((char *)maddr + ehdr->e_phoff); 1089 1090 /* 1091 * If padding is required at the front of the image, obtain that now. 1092 * Note, if we've already obtained a reservation from anonymous memory 1093 * then this reservation will already include suitable padding. 1094 * Otherwise this reservation is backed by the file, or in the case of 1095 * a fixed image, doesn't yet exist. Map the padding so that it is 1096 * suitably protected (PROT_NONE), and insure the first segment of the 1097 * file is mapped to its correct location. 1098 */ 1099 if (padsize) { 1100 if (amret == AM_NOSUP) { 1101 if (dz_map(lml, raddr, padpsize, PROT_NONE, 1102 (MAP_PRIVATE | MAP_FIXED | MAP_NORESERVE)) == 1103 MAP_FAILED) 1104 return (0); 1105 1106 skipfseg = 0; 1107 } 1108 rsize -= padpsize; 1109 } 1110 1111 /* 1112 * Map individual segments. For a fixed image, these will each be 1113 * unique mappings. For a reservation these will fill in the 1114 * reservation. 1115 */ 1116 for (phdr = fphdr; phdr <= lphdr; 1117 phdr = (Phdr *)((Off)phdr + ehdr->e_phentsize)) { 1118 caddr_t addr; 1119 Off mlen, flen; 1120 size_t size; 1121 1122 /* 1123 * Skip non-loadable segments or segments that don't occupy 1124 * any memory. 1125 */ 1126 if ((phdr->p_type != PT_LOAD) || (phdr->p_memsz == 0)) 1127 continue; 1128 1129 /* 1130 * Establish this segments address relative to our base. 1131 */ 1132 addr = (caddr_t)M_PTRUNC((ulong_t)(phdr->p_vaddr + 1133 (fixed ? 0 : faddr))); 1134 1135 /* 1136 * Determine the mapping protection from the segment attributes. 1137 * Also determine the etext address from the last loadable 1138 * segment which has permissions but no write access. 1139 */ 1140 mperm = 0; 1141 if (phdr->p_flags) { 1142 if (phdr->p_flags & PF_R) 1143 mperm |= PROT_READ; 1144 if (phdr->p_flags & PF_X) 1145 mperm |= PROT_EXEC; 1146 if (phdr->p_flags & PF_W) 1147 mperm |= PROT_WRITE; 1148 else 1149 fmap->fm_etext = phdr->p_vaddr + phdr->p_memsz + 1150 (ulong_t)(fixed ? 0 : faddr); 1151 } 1152 1153 /* 1154 * Determine the type of mapping required. 1155 */ 1156 if ((phdr->p_filesz == 0) && (phdr->p_flags == 0)) { 1157 /* 1158 * If this segment has no backing file and no flags 1159 * specified, then it defines a reservation. At this 1160 * point all standard loadable segments will have been 1161 * processed. The segment reservation is mapped 1162 * directly from /dev/null. 1163 */ 1164 if (nu_map(lml, (caddr_t)addr, phdr->p_memsz, PROT_NONE, 1165 MAP_FIXED | MAP_PRIVATE) == MAP_FAILED) 1166 return (0); 1167 1168 mlen = phdr->p_memsz; 1169 flen = 0; 1170 1171 } else if (phdr->p_filesz == 0) { 1172 /* 1173 * If this segment has no backing file then it defines a 1174 * nobits segment and is mapped directly from /dev/zero. 1175 */ 1176 if (dz_map(lml, (caddr_t)addr, phdr->p_memsz, mperm, 1177 MAP_FIXED | MAP_PRIVATE) == MAP_FAILED) 1178 return (0); 1179 1180 mlen = phdr->p_memsz; 1181 flen = 0; 1182 1183 } else { 1184 Off foff; 1185 1186 /* 1187 * This mapping originates from the file. Determine the 1188 * file offset to which the mapping will be directed 1189 * (must be aligned) and how much to map (might be more 1190 * than the file in the case of .bss). 1191 */ 1192 foff = M_PTRUNC((ulong_t)phdr->p_offset); 1193 mlen = phdr->p_memsz + (phdr->p_offset - foff); 1194 flen = phdr->p_filesz + (phdr->p_offset - foff); 1195 1196 /* 1197 * If this is a non-fixed, non-anonymous mapping, and no 1198 * padding is involved, then the first loadable segment 1199 * is already part of the initial reservation. In this 1200 * case there is no need to remap this segment. 1201 */ 1202 if ((skipfseg == 0) || (phdr != fphdr)) { 1203 int phdr_mperm = mperm; 1204 /* 1205 * If this segments memsz is greater that its 1206 * filesz then the difference must be zeroed. 1207 * Make sure this segment is writable. 1208 */ 1209 if (phdr->p_memsz > phdr->p_filesz) 1210 mperm |= PROT_WRITE; 1211 1212 if (elf_map_textdata((caddr_t)addr, flen, 1213 mperm, phdr_mperm, 1214 (MAP_FIXED | MAP_PRIVATE), fd, foff) == 1215 MAP_FAILED) { 1216 int err = errno; 1217 eprintf(lml, ERR_FATAL, 1218 MSG_INTL(MSG_SYS_MMAP), name, 1219 strerror(err)); 1220 return (0); 1221 } 1222 } 1223 1224 /* 1225 * If the memory occupancy of the segment overflows the 1226 * definition in the file, we need to "zero out" the end 1227 * of the mapping we've established, and if necessary, 1228 * map some more space from /dev/zero. Note, zero'ed 1229 * memory must end on a double word boundary to satisfy 1230 * zero(). 1231 */ 1232 if (phdr->p_memsz > phdr->p_filesz) { 1233 caddr_t zaddr; 1234 size_t zlen, zplen; 1235 Off fend; 1236 1237 foff = (Off)(phdr->p_vaddr + phdr->p_filesz + 1238 (fixed ? 0 : faddr)); 1239 zaddr = (caddr_t)M_PROUND(foff); 1240 zplen = (size_t)(zaddr - foff); 1241 1242 fend = (Off)S_DROUND((size_t)(phdr->p_vaddr + 1243 phdr->p_memsz + (fixed ? 0 : faddr))); 1244 zlen = (size_t)(fend - foff); 1245 1246 /* 1247 * Determine whether the number of bytes that 1248 * must be zero'ed overflow to the next page. 1249 * If not, simply clear the exact bytes 1250 * (filesz to memsz) from this page. Otherwise, 1251 * clear the remaining bytes of this page, and 1252 * map an following pages from /dev/zero. 1253 */ 1254 if (zlen < zplen) 1255 zero((caddr_t)foff, (long)zlen); 1256 else { 1257 zero((caddr_t)foff, (long)zplen); 1258 1259 if ((zlen = (fend - (Off)zaddr)) > 0) { 1260 if (dz_map(lml, zaddr, zlen, 1261 mperm, 1262 MAP_FIXED | MAP_PRIVATE) == 1263 MAP_FAILED) 1264 return (0); 1265 } 1266 } 1267 } 1268 } 1269 1270 /* 1271 * Unmap anything from the last mapping address to this one and 1272 * update the mapping claim pointer. 1273 */ 1274 if ((fixed == 0) && ((size = addr - maddr) != 0)) { 1275 (void) munmap(maddr, size); 1276 rsize -= size; 1277 } 1278 1279 /* 1280 * Retain this segments mapping information. 1281 */ 1282 mmaps[*mmapcnt].m_vaddr = addr; 1283 mmaps[*mmapcnt].m_msize = mlen; 1284 mmaps[*mmapcnt].m_fsize = flen; 1285 mmaps[*mmapcnt].m_perm = mperm; 1286 (*mmapcnt)++; 1287 1288 maddr = addr + M_PROUND(mlen); 1289 rsize -= M_PROUND(mlen); 1290 } 1291 1292 /* 1293 * If padding is required at the end of the image, obtain that now. 1294 * Note, if we've already obtained a reservation from anonymous memory 1295 * then this reservation will already include suitable padding. 1296 */ 1297 if (padsize) { 1298 if (amret == AM_NOSUP) { 1299 /* 1300 * maddr is currently page aligned from the last segment 1301 * mapping. 1302 */ 1303 if (dz_map(lml, maddr, padsize, PROT_NONE, 1304 (MAP_PRIVATE | MAP_FIXED | MAP_NORESERVE)) == 1305 MAP_FAILED) 1306 return (0); 1307 } 1308 maddr += padsize; 1309 rsize -= padsize; 1310 } 1311 1312 /* 1313 * Unmap any final reservation. 1314 */ 1315 if ((fixed == 0) && (rsize != 0)) 1316 (void) munmap(maddr, rsize); 1317 1318 return (faddr); 1319 } 1320 1321 /* 1322 * A null symbol interpretor. Used if a filter has no associated filtees. 1323 */ 1324 /* ARGSUSED0 */ 1325 static Sym * 1326 elf_null_find_sym(Slookup *slp, Rt_map **dlmp, uint_t *binfo, int *in_nfavl) 1327 { 1328 return ((Sym *)0); 1329 } 1330 1331 /* 1332 * Disable filtee use. 1333 */ 1334 static void 1335 elf_disable_filtee(Rt_map *lmp, Dyninfo *dip) 1336 { 1337 dip->di_info = 0; 1338 1339 if ((dip->di_flags & FLG_DI_SYMFLTR) == 0) { 1340 /* 1341 * If this is an object filter, free the filtee's duplication. 1342 */ 1343 if (OBJFLTRNDX(lmp) != FLTR_DISABLED) { 1344 free(REFNAME(lmp)); 1345 REFNAME(lmp) = (char *)0; 1346 OBJFLTRNDX(lmp) = FLTR_DISABLED; 1347 1348 /* 1349 * Indicate that this filtee is no longer available. 1350 */ 1351 if (dip->di_flags & FLG_DI_STDFLTR) 1352 SYMINTP(lmp) = elf_null_find_sym; 1353 1354 } 1355 } else if (dip->di_flags & FLG_DI_STDFLTR) { 1356 /* 1357 * Indicate that this standard filtee is no longer available. 1358 */ 1359 if (SYMSFLTRCNT(lmp)) 1360 SYMSFLTRCNT(lmp)--; 1361 } else { 1362 /* 1363 * Indicate that this auxiliary filtee is no longer available. 1364 */ 1365 if (SYMAFLTRCNT(lmp)) 1366 SYMAFLTRCNT(lmp)--; 1367 } 1368 dip->di_flags &= ~MSK_DI_FILTER; 1369 } 1370 1371 /* 1372 * Find symbol interpreter - filters. 1373 * This function is called when the symbols from a shared object should 1374 * be resolved from the shared objects filtees instead of from within itself. 1375 * 1376 * A symbol name of 0 is used to trigger filtee loading. 1377 */ 1378 static Sym * 1379 _elf_lookup_filtee(Slookup *slp, Rt_map **dlmp, uint_t *binfo, uint_t ndx, 1380 int *in_nfavl) 1381 { 1382 const char *name = slp->sl_name, *filtees; 1383 Rt_map *clmp = slp->sl_cmap; 1384 Rt_map *ilmp = slp->sl_imap; 1385 Pnode *pnp, **pnpp; 1386 int any; 1387 Dyninfo *dip = &DYNINFO(ilmp)[ndx]; 1388 Lm_list *lml = LIST(ilmp); 1389 1390 /* 1391 * Indicate that the filter has been used. If a binding already exists 1392 * to the caller, indicate that this object is referenced. This insures 1393 * we don't generate false unreferenced diagnostics from ldd -u/U or 1394 * debugging. Don't create a binding regardless, as this filter may 1395 * have been dlopen()'ed. 1396 */ 1397 if (name && (ilmp != clmp)) { 1398 Word tracing = (LIST(clmp)->lm_flags & 1399 (LML_FLG_TRC_UNREF | LML_FLG_TRC_UNUSED)); 1400 1401 if (tracing || DBG_ENABLED) { 1402 Bnd_desc *bdp; 1403 Aliste idx; 1404 1405 FLAGS1(ilmp) |= FL1_RT_USED; 1406 1407 if ((tracing & LML_FLG_TRC_UNREF) || DBG_ENABLED) { 1408 for (APLIST_TRAVERSE(CALLERS(ilmp), idx, bdp)) { 1409 if (bdp->b_caller == clmp) { 1410 bdp->b_flags |= BND_REFER; 1411 break; 1412 } 1413 } 1414 } 1415 } 1416 } 1417 1418 /* 1419 * If this is the first call to process this filter, establish the 1420 * filtee list. If a configuration file exists, determine if any 1421 * filtee associations for this filter, and its filtee reference, are 1422 * defined. Otherwise, process the filtee reference. Any token 1423 * expansion is also completed at this point (i.e., $PLATFORM). 1424 */ 1425 filtees = (char *)STRTAB(ilmp) + DYN(ilmp)[ndx].d_un.d_val; 1426 if (dip->di_info == 0) { 1427 if (rtld_flags2 & RT_FL2_FLTCFG) 1428 dip->di_info = elf_config_flt(lml, PATHNAME(ilmp), 1429 filtees); 1430 1431 if (dip->di_info == 0) { 1432 DBG_CALL(Dbg_file_filter(lml, NAME(ilmp), filtees, 0)); 1433 if ((lml->lm_flags & 1434 (LML_FLG_TRC_VERBOSE | LML_FLG_TRC_SEARCH)) && 1435 ((FLAGS1(ilmp) & FL1_RT_LDDSTUB) == 0)) 1436 (void) printf(MSG_INTL(MSG_LDD_FIL_FILTER), 1437 NAME(ilmp), filtees); 1438 1439 if ((dip->di_info = (void *)expand_paths(ilmp, 1440 filtees, 0, 0)) == 0) { 1441 elf_disable_filtee(ilmp, dip); 1442 return ((Sym *)0); 1443 } 1444 } 1445 } 1446 1447 /* 1448 * Traverse the filtee list, dlopen()'ing any objects specified and 1449 * using their group handle to lookup the symbol. 1450 */ 1451 for (any = 0, pnpp = (Pnode **)&(dip->di_info), pnp = *pnpp; pnp; 1452 pnpp = &pnp->p_next, pnp = *pnpp) { 1453 int mode; 1454 Grp_hdl *ghp; 1455 Rt_map *nlmp = 0; 1456 1457 if (pnp->p_len == 0) 1458 continue; 1459 1460 /* 1461 * Establish the mode of the filtee from the filter. As filtees 1462 * are loaded via a dlopen(), make sure that RTLD_GROUP is set 1463 * and the filtees aren't global. It would be nice to have 1464 * RTLD_FIRST used here also, but as filters got out long before 1465 * RTLD_FIRST was introduced it's a little too late now. 1466 */ 1467 mode = MODE(ilmp) | RTLD_GROUP; 1468 mode &= ~RTLD_GLOBAL; 1469 1470 /* 1471 * Insure that any auxiliary filter can locate symbols from its 1472 * caller. 1473 */ 1474 if (dip->di_flags & FLG_DI_AUXFLTR) 1475 mode |= RTLD_PARENT; 1476 1477 /* 1478 * Process any hardware capability directory. Establish a new 1479 * link-map control list from which to analyze any newly added 1480 * objects. 1481 */ 1482 if ((pnp->p_info == 0) && (pnp->p_orig & PN_TKN_HWCAP)) { 1483 Lm_cntl *lmc; 1484 Aliste lmco; 1485 1486 if (FLAGS(lml->lm_head) & FLG_RT_RELOCED) { 1487 if ((lmc = alist_append(&lml->lm_lists, 0, 1488 sizeof (Lm_cntl), AL_CNT_LMLISTS)) == 0) 1489 return ((Sym *)0); 1490 lmco = (Aliste)((char *)lmc - 1491 (char *)lml->lm_lists); 1492 } else { 1493 lmc = 0; 1494 lmco = ALIST_OFF_DATA; 1495 } 1496 1497 pnp = hwcap_filtees(pnpp, lmco, lmc, dip, ilmp, filtees, 1498 mode, (FLG_RT_HANDLE | FLG_RT_HWCAP), in_nfavl); 1499 1500 /* 1501 * Now that any hardware capability objects have been 1502 * processed, remove any link-map control list. 1503 */ 1504 if (lmc) 1505 remove_cntl(lml, lmco); 1506 } 1507 1508 if (pnp->p_len == 0) 1509 continue; 1510 1511 /* 1512 * Process an individual filtee. 1513 */ 1514 if (pnp->p_info == 0) { 1515 const char *filtee = pnp->p_name; 1516 int audit = 0; 1517 1518 DBG_CALL(Dbg_file_filtee(lml, NAME(ilmp), filtee, 0)); 1519 1520 ghp = 0; 1521 1522 /* 1523 * Determine if the reference link map is already 1524 * loaded. As an optimization compare the filtee with 1525 * our interpretor. The most common filter is 1526 * libdl.so.1, which is a filter on ld.so.1. 1527 */ 1528 #if defined(_ELF64) 1529 if (strcmp(filtee, MSG_ORIG(MSG_PTH_RTLD_64)) == 0) { 1530 #else 1531 if (strcmp(filtee, MSG_ORIG(MSG_PTH_RTLD)) == 0) { 1532 #endif 1533 /* 1534 * Create an association between ld.so.1 and the 1535 * filter. As an optimization, a handle for 1536 * ld.so.1 itself (required for the dlopen() 1537 * family filtering mechanism) shouldn't search 1538 * any dependencies of ld.so.1. Omitting 1539 * GPD_ADDEPS prevents the addition of any 1540 * ld.so.1 dependencies to this handle. 1541 */ 1542 nlmp = lml_rtld.lm_head; 1543 if ((ghp = hdl_create(&lml_rtld, nlmp, ilmp, 1544 (GPH_LDSO | GPH_FIRST | GPH_FILTEE), 1545 (GPD_DLSYM | GPD_RELOC), GPD_PARENT)) == 0) 1546 nlmp = 0; 1547 1548 /* 1549 * Establish the filter handle to prevent any 1550 * recursion. 1551 */ 1552 if (nlmp && ghp) 1553 pnp->p_info = (void *)ghp; 1554 1555 /* 1556 * Audit the filter/filtee established. Ignore 1557 * any return from the auditor, as we can't 1558 * allow ignore filtering to ld.so.1, otherwise 1559 * nothing is going to work. 1560 */ 1561 if (nlmp && ((lml->lm_tflags | FLAGS1(ilmp)) & 1562 LML_TFLG_AUD_OBJFILTER)) 1563 (void) audit_objfilter(ilmp, filtees, 1564 nlmp, 0); 1565 1566 } else { 1567 Rej_desc rej = { 0 }; 1568 Lm_cntl *lmc; 1569 Aliste lmco; 1570 1571 /* 1572 * Establish a new link-map control list from 1573 * which to analyze any newly added objects. 1574 */ 1575 if (FLAGS(lml->lm_head) & FLG_RT_RELOCED) { 1576 if ((lmc = 1577 alist_append(&lml->lm_lists, 0, 1578 sizeof (Lm_cntl), 1579 AL_CNT_LMLISTS)) == 0) 1580 return ((Sym *)0); 1581 lmco = (Aliste)((char *)lmc - 1582 (char *)lml->lm_lists); 1583 } else { 1584 lmc = 0; 1585 lmco = ALIST_OFF_DATA; 1586 } 1587 1588 /* 1589 * Load the filtee. Note, an auditor can 1590 * provide an alternative name. 1591 */ 1592 if ((nlmp = load_path(lml, lmco, &(pnp->p_name), 1593 ilmp, mode, FLG_RT_HANDLE, &ghp, 0, 1594 &rej, in_nfavl)) == 0) { 1595 file_notfound(LIST(ilmp), filtee, ilmp, 1596 FLG_RT_HANDLE, &rej); 1597 remove_rej(&rej); 1598 } 1599 filtee = pnp->p_name; 1600 1601 /* 1602 * Establish the filter handle to prevent any 1603 * recursion. 1604 */ 1605 if (nlmp && ghp) { 1606 ghp->gh_flags |= GPH_FILTEE; 1607 pnp->p_info = (void *)ghp; 1608 1609 FLAGS1(nlmp) |= FL1_RT_USED; 1610 } 1611 1612 /* 1613 * Audit the filter/filtee established. A 1614 * return of 0 indicates the auditor wishes to 1615 * ignore this filtee. 1616 */ 1617 if (nlmp && ((lml->lm_tflags | FLAGS1(ilmp)) & 1618 LML_TFLG_AUD_OBJFILTER)) { 1619 if (audit_objfilter(ilmp, filtees, 1620 nlmp, 0) == 0) { 1621 audit = 1; 1622 nlmp = 0; 1623 } 1624 } 1625 1626 /* 1627 * Finish processing the objects associated with 1628 * this request. Create an association between 1629 * this object and the originating filter to 1630 * provide sufficient information to tear down 1631 * this filtee if necessary. 1632 */ 1633 if (nlmp && ghp && ((analyze_lmc(lml, lmco, 1634 nlmp, in_nfavl) == 0) || (relocate_lmc(lml, 1635 lmco, ilmp, nlmp, in_nfavl) == 0))) 1636 nlmp = 0; 1637 1638 /* 1639 * If the filtee has been successfully 1640 * processed, then create an association 1641 * between the filter and filtee. This 1642 * association provides sufficient information 1643 * to tear down the filter and filtee if 1644 * necessary. 1645 */ 1646 DBG_CALL(Dbg_file_hdl_title(DBG_HDL_ADD)); 1647 if (nlmp && ghp && 1648 (hdl_add(ghp, ilmp, GPD_FILTER) == 0)) 1649 nlmp = 0; 1650 1651 /* 1652 * If this filtee loading has failed, and we've 1653 * created a new link-map control list to which 1654 * this request has added objects, then remove 1655 * all the objects that have been associated to 1656 * this request. 1657 */ 1658 if ((nlmp == 0) && lmc && lmc->lc_head) 1659 remove_lmc(lml, clmp, lmc, lmco, name); 1660 1661 /* 1662 * Remove any link-map control list that was 1663 * created. 1664 */ 1665 if (lmc) 1666 remove_cntl(lml, lmco); 1667 } 1668 1669 /* 1670 * Generate a diagnostic if the filtee couldn't be 1671 * loaded, null out the pnode entry, and continue 1672 * the search. Otherwise, retain this group handle 1673 * for future symbol searches. 1674 */ 1675 if (nlmp == 0) { 1676 DBG_CALL(Dbg_file_filtee(lml, 0, filtee, 1677 audit)); 1678 1679 pnp->p_info = 0; 1680 pnp->p_len = 0; 1681 continue; 1682 } 1683 } 1684 1685 ghp = (Grp_hdl *)pnp->p_info; 1686 1687 /* 1688 * If we're just here to trigger filtee loading skip the symbol 1689 * lookup so we'll continue looking for additional filtees. 1690 */ 1691 if (name) { 1692 Grp_desc *gdp; 1693 Sym *sym = 0; 1694 Aliste idx; 1695 Slookup sl = *slp; 1696 1697 sl.sl_flags |= LKUP_FIRST; 1698 any++; 1699 1700 /* 1701 * Look for the symbol in the handles dependencies. 1702 */ 1703 for (ALIST_TRAVERSE(ghp->gh_depends, idx, gdp)) { 1704 if ((gdp->gd_flags & GPD_DLSYM) == 0) 1705 continue; 1706 1707 /* 1708 * If our parent is a dependency don't look at 1709 * it (otherwise we are in a recursive loop). 1710 * This situation can occur with auxiliary 1711 * filters if the filtee has a dependency on the 1712 * filter. This dependency isn't necessary as 1713 * auxiliary filters are opened RTLD_PARENT, but 1714 * users may still unknowingly add an explicit 1715 * dependency to the parent. 1716 */ 1717 if ((sl.sl_imap = gdp->gd_depend) == ilmp) 1718 continue; 1719 1720 if (((sym = SYMINTP(sl.sl_imap)(&sl, dlmp, 1721 binfo, in_nfavl)) != 0) || 1722 (ghp->gh_flags & GPH_FIRST)) 1723 break; 1724 } 1725 1726 /* 1727 * If a symbol has been found, indicate the binding 1728 * and return the symbol. 1729 */ 1730 if (sym) { 1731 *binfo |= DBG_BINFO_FILTEE; 1732 return (sym); 1733 } 1734 } 1735 1736 /* 1737 * If this object is tagged to terminate filtee processing we're 1738 * done. 1739 */ 1740 if (FLAGS1(ghp->gh_ownlmp) & FL1_RT_ENDFILTE) 1741 break; 1742 } 1743 1744 /* 1745 * If we're just here to trigger filtee loading then we're done. 1746 */ 1747 if (name == 0) 1748 return ((Sym *)0); 1749 1750 /* 1751 * If no filtees have been found for a filter, clean up any Pnode 1752 * structures and disable their search completely. For auxiliary 1753 * filters we can reselect the symbol search function so that we never 1754 * enter this routine again for this object. For standard filters we 1755 * use the null symbol routine. 1756 */ 1757 if (any == 0) { 1758 remove_pnode((Pnode *)dip->di_info); 1759 elf_disable_filtee(ilmp, dip); 1760 return ((Sym *)0); 1761 } 1762 1763 return ((Sym *)0); 1764 } 1765 1766 /* 1767 * Focal point for disabling error messages for auxiliary filters. As an 1768 * auxiliary filter allows for filtee use, but provides a fallback should a 1769 * filtee not exist (or fail to load), any errors generated as a consequence of 1770 * trying to load the filtees are typically suppressed. Setting RT_FL_SILENCERR 1771 * suppresses errors generated by eprint(), but insures a debug diagnostic is 1772 * produced. ldd(1) employs printf(), and here, the selection of whether to 1773 * print a diagnostic in regards to auxiliary filters is a little more complex. 1774 * 1775 * . The determination of whether to produce an ldd message, or a fatal 1776 * error message is driven by LML_FLG_TRC_ENABLE. 1777 * . More detailed ldd messages may also be driven off of LML_FLG_TRC_WARN, 1778 * (ldd -d/-r), LML_FLG_TRC_VERBOSE (ldd -v), LML_FLG_TRC_SEARCH (ldd -s), 1779 * and LML_FLG_TRC_UNREF/LML_FLG_TRC_UNUSED (ldd -U/-u). 1780 * 1781 * . If the calling object is lddstub, then several classes of message are 1782 * suppressed. The user isn't trying to diagnose lddstub, this is simply 1783 * a stub executable employed to preload a user specified library against. 1784 * 1785 * . If RT_FL_SILENCERR is in effect then any generic ldd() messages should 1786 * be suppressed. All detailed ldd messages should still be produced. 1787 */ 1788 Sym * 1789 elf_lookup_filtee(Slookup *slp, Rt_map **dlmp, uint_t *binfo, uint_t ndx, 1790 int *in_nfavl) 1791 { 1792 Sym *sym; 1793 Dyninfo *dip = &DYNINFO(slp->sl_imap)[ndx]; 1794 int silent = 0; 1795 1796 /* 1797 * Make sure this entry is still acting as a filter. We may have tried 1798 * to process this previously, and disabled it if the filtee couldn't 1799 * be processed. However, other entries may provide different filtees 1800 * that are yet to be completed. 1801 */ 1802 if (dip->di_flags == 0) 1803 return ((Sym *)0); 1804 1805 /* 1806 * Indicate whether an error message is required should this filtee not 1807 * be found, based on the type of filter. 1808 */ 1809 if ((dip->di_flags & FLG_DI_AUXFLTR) && 1810 ((rtld_flags & (RT_FL_WARNFLTR | RT_FL_SILENCERR)) == 0)) { 1811 rtld_flags |= RT_FL_SILENCERR; 1812 silent = 1; 1813 } 1814 1815 sym = _elf_lookup_filtee(slp, dlmp, binfo, ndx, in_nfavl); 1816 1817 if (silent) 1818 rtld_flags &= ~RT_FL_SILENCERR; 1819 1820 return (sym); 1821 } 1822 1823 /* 1824 * Compute the elf hash value (as defined in the ELF access library). 1825 * The form of the hash table is: 1826 * 1827 * |--------------| 1828 * | # of buckets | 1829 * |--------------| 1830 * | # of chains | 1831 * |--------------| 1832 * | bucket[] | 1833 * |--------------| 1834 * | chain[] | 1835 * |--------------| 1836 */ 1837 ulong_t 1838 elf_hash(const char *name) 1839 { 1840 uint_t hval = 0; 1841 1842 while (*name) { 1843 uint_t g; 1844 hval = (hval << 4) + *name++; 1845 if ((g = (hval & 0xf0000000)) != 0) 1846 hval ^= g >> 24; 1847 hval &= ~g; 1848 } 1849 return ((ulong_t)hval); 1850 } 1851 1852 /* 1853 * If flag argument has LKUP_SPEC set, we treat undefined symbols of type 1854 * function specially in the executable - if they have a value, even though 1855 * undefined, we use that value. This allows us to associate all references 1856 * to a function's address to a single place in the process: the plt entry 1857 * for that function in the executable. Calls to lookup from plt binding 1858 * routines do NOT set LKUP_SPEC in the flag. 1859 */ 1860 Sym * 1861 elf_find_sym(Slookup *slp, Rt_map **dlmp, uint_t *binfo, int *in_nfavl) 1862 { 1863 const char *name = slp->sl_name; 1864 Rt_map *ilmp = slp->sl_imap; 1865 ulong_t hash = slp->sl_hash; 1866 uint_t ndx, htmp, buckets, *chainptr; 1867 Sym *sym, *symtabptr; 1868 char *strtabptr, *strtabname; 1869 uint_t flags1; 1870 Syminfo *sip; 1871 1872 /* 1873 * If we're only here to establish a symbols index, skip the diagnostic 1874 * used to trace a symbol search. 1875 */ 1876 if ((slp->sl_flags & LKUP_SYMNDX) == 0) 1877 DBG_CALL(Dbg_syms_lookup(ilmp, name, MSG_ORIG(MSG_STR_ELF))); 1878 1879 if (HASH(ilmp) == 0) 1880 return ((Sym *)0); 1881 1882 buckets = HASH(ilmp)[0]; 1883 /* LINTED */ 1884 htmp = (uint_t)hash % buckets; 1885 1886 /* 1887 * Get the first symbol on hash chain and initialize the string 1888 * and symbol table pointers. 1889 */ 1890 if ((ndx = HASH(ilmp)[htmp + 2]) == 0) 1891 return ((Sym *)0); 1892 1893 chainptr = HASH(ilmp) + 2 + buckets; 1894 strtabptr = STRTAB(ilmp); 1895 symtabptr = SYMTAB(ilmp); 1896 1897 while (ndx) { 1898 sym = symtabptr + ndx; 1899 strtabname = strtabptr + sym->st_name; 1900 1901 /* 1902 * Compare the symbol found with the name required. If the 1903 * names don't match continue with the next hash entry. 1904 */ 1905 if ((*strtabname++ != *name) || strcmp(strtabname, &name[1])) { 1906 if ((ndx = chainptr[ndx]) != 0) 1907 continue; 1908 return ((Sym *)0); 1909 } 1910 1911 /* 1912 * The Solaris ld does not put DT_VERSYM in the dynamic 1913 * section, but the GNU ld does. The GNU runtime linker 1914 * interprets the top bit of the 16-bit Versym value 1915 * (0x8000) as the "hidden" bit. If this bit is set, 1916 * the linker is supposed to act as if that symbol does 1917 * not exist. The hidden bit supports their versioning 1918 * scheme, which allows multiple incompatible functions 1919 * with the same name to exist at different versions 1920 * within an object. The Solaris linker does not support this 1921 * mechanism, or the model of interface evolution that 1922 * it allows, but we honor the hidden bit in GNU ld 1923 * produced objects in order to interoperate with them. 1924 */ 1925 if ((VERSYM(ilmp) != NULL) && 1926 ((VERSYM(ilmp)[ndx] & 0x8000) != 0)) { 1927 DBG_CALL(Dbg_syms_ignore_gnuver(ilmp, name, 1928 ndx, VERSYM(ilmp)[ndx])); 1929 if ((ndx = chainptr[ndx]) != 0) 1930 continue; 1931 return ((Sym *)0); 1932 } 1933 1934 /* 1935 * If we're only here to establish a symbols index, we're done. 1936 */ 1937 if (slp->sl_flags & LKUP_SYMNDX) 1938 return (sym); 1939 1940 /* 1941 * If we find a match and the symbol is defined, return the 1942 * symbol pointer and the link map in which it was found. 1943 */ 1944 if (sym->st_shndx != SHN_UNDEF) { 1945 *dlmp = ilmp; 1946 *binfo |= DBG_BINFO_FOUND; 1947 if ((FLAGS(ilmp) & FLG_RT_OBJINTPO) || 1948 ((FLAGS(ilmp) & FLG_RT_SYMINTPO) && 1949 is_sym_interposer(ilmp, sym))) 1950 *binfo |= DBG_BINFO_INTERPOSE; 1951 break; 1952 1953 /* 1954 * If we find a match and the symbol is undefined, the 1955 * symbol type is a function, and the value of the symbol 1956 * is non zero, then this is a special case. This allows 1957 * the resolution of a function address to the plt[] entry. 1958 * See SPARC ABI, Dynamic Linking, Function Addresses for 1959 * more details. 1960 */ 1961 } else if ((slp->sl_flags & LKUP_SPEC) && 1962 (FLAGS(ilmp) & FLG_RT_ISMAIN) && (sym->st_value != 0) && 1963 (ELF_ST_TYPE(sym->st_info) == STT_FUNC)) { 1964 *dlmp = ilmp; 1965 *binfo |= (DBG_BINFO_FOUND | DBG_BINFO_PLTADDR); 1966 if ((FLAGS(ilmp) & FLG_RT_OBJINTPO) || 1967 ((FLAGS(ilmp) & FLG_RT_SYMINTPO) && 1968 is_sym_interposer(ilmp, sym))) 1969 *binfo |= DBG_BINFO_INTERPOSE; 1970 return (sym); 1971 } 1972 1973 /* 1974 * Undefined symbol. 1975 */ 1976 return ((Sym *)0); 1977 } 1978 1979 /* 1980 * We've found a match. Determine if the defining object contains 1981 * symbol binding information. 1982 */ 1983 if ((sip = SYMINFO(ilmp)) != 0) 1984 sip += ndx; 1985 1986 /* 1987 * If this definition is a singleton, and we haven't followed a default 1988 * symbol search knowing that we're looking for a singleton (presumably 1989 * because the symbol definition has been changed since the referring 1990 * object was built), then reject this binding so that the caller can 1991 * fall back to a standard symbol search. 1992 */ 1993 if ((ELF_ST_VISIBILITY(sym->st_other) == STV_SINGLETON) && 1994 (((slp->sl_flags & LKUP_STANDARD) == 0) || 1995 (((slp->sl_flags & LKUP_SINGLETON) == 0) && 1996 (LIST(ilmp)->lm_flags & LML_FLG_GROUPSEXIST)))) { 1997 DBG_CALL(Dbg_bind_reject(slp->sl_cmap, ilmp, name, 1998 DBG_BNDREJ_SINGLE)); 1999 *binfo |= BINFO_REJSINGLE; 2000 *binfo &= ~DBG_BINFO_MSK; 2001 return ((Sym *)0); 2002 } 2003 2004 /* 2005 * If this is a direct binding request, but the symbol definition has 2006 * disabled directly binding to it (presumably because the symbol 2007 * definition has been changed since the referring object was built), 2008 * indicate this failure so that the caller can fall back to a standard 2009 * symbol search. 2010 */ 2011 if (sip && (slp->sl_flags & LKUP_DIRECT) && 2012 (sip->si_flags & SYMINFO_FLG_NOEXTDIRECT)) { 2013 DBG_CALL(Dbg_bind_reject(slp->sl_cmap, ilmp, name, 2014 DBG_BNDREJ_NODIR)); 2015 *binfo |= BINFO_REJDIRECT; 2016 *binfo &= ~DBG_BINFO_MSK; 2017 return ((Sym *)0); 2018 } 2019 2020 /* 2021 * Determine whether this object is acting as a filter. 2022 */ 2023 if (((flags1 = FLAGS1(ilmp)) & MSK_RT_FILTER) == 0) 2024 return (sym); 2025 2026 /* 2027 * Determine if this object offers per-symbol filtering, and if so, 2028 * whether this symbol references a filtee. 2029 */ 2030 if (sip && (flags1 & (FL1_RT_SYMSFLTR | FL1_RT_SYMAFLTR))) { 2031 /* 2032 * If this is a standard filter reference, and no standard 2033 * filtees remain to be inspected, we're done. If this is an 2034 * auxiliary filter reference, and no auxiliary filtees remain, 2035 * we'll fall through in case any object filtering is available. 2036 */ 2037 if ((sip->si_flags & SYMINFO_FLG_FILTER) && 2038 (SYMSFLTRCNT(ilmp) == 0)) 2039 return ((Sym *)0); 2040 2041 if ((sip->si_flags & SYMINFO_FLG_FILTER) || 2042 ((sip->si_flags & SYMINFO_FLG_AUXILIARY) && 2043 SYMAFLTRCNT(ilmp))) { 2044 Sym *fsym; 2045 2046 /* 2047 * This symbol has an associated filtee. Lookup the 2048 * symbol in the filtee, and if it is found return it. 2049 * If the symbol doesn't exist, and this is a standard 2050 * filter, return an error, otherwise fall through to 2051 * catch any object filtering that may be available. 2052 */ 2053 if ((fsym = elf_lookup_filtee(slp, dlmp, binfo, 2054 sip->si_boundto, in_nfavl)) != 0) 2055 return (fsym); 2056 if (sip->si_flags & SYMINFO_FLG_FILTER) 2057 return ((Sym *)0); 2058 } 2059 } 2060 2061 /* 2062 * Determine if this object provides global filtering. 2063 */ 2064 if (flags1 & (FL1_RT_OBJSFLTR | FL1_RT_OBJAFLTR)) { 2065 Sym *fsym; 2066 2067 if (OBJFLTRNDX(ilmp) != FLTR_DISABLED) { 2068 /* 2069 * This object has an associated filtee. Lookup the 2070 * symbol in the filtee, and if it is found return it. 2071 * If the symbol doesn't exist, and this is a standard 2072 * filter, return and error, otherwise return the symbol 2073 * within the filter itself. 2074 */ 2075 if ((fsym = elf_lookup_filtee(slp, dlmp, binfo, 2076 OBJFLTRNDX(ilmp), in_nfavl)) != 0) 2077 return (fsym); 2078 } 2079 2080 if (flags1 & FL1_RT_OBJSFLTR) 2081 return ((Sym *)0); 2082 } 2083 return (sym); 2084 } 2085 2086 /* 2087 * Create a new Rt_map structure for an ELF object and initialize 2088 * all values. 2089 */ 2090 Rt_map * 2091 elf_new_lm(Lm_list *lml, const char *pname, const char *oname, Dyn *ld, 2092 ulong_t addr, ulong_t etext, Aliste lmco, ulong_t msize, ulong_t entry, 2093 ulong_t paddr, ulong_t padimsize, Mmap *mmaps, uint_t mmapcnt, 2094 int *in_nfavl) 2095 { 2096 Rt_map *lmp; 2097 ulong_t base, fltr = 0, audit = 0, cfile = 0, crle = 0; 2098 Xword rpath = 0; 2099 Ehdr *ehdr = (Ehdr *)addr; 2100 2101 DBG_CALL(Dbg_file_elf(lml, pname, (ulong_t)ld, addr, msize, entry, 2102 lml->lm_lmidstr, lmco)); 2103 2104 /* 2105 * Allocate space for the link-map and private elf information. Once 2106 * these are allocated and initialized, we can use remove_so(0, lmp) to 2107 * tear down the link-map should any failures occur. 2108 */ 2109 if ((lmp = calloc(sizeof (Rt_map), 1)) == 0) 2110 return (0); 2111 if ((ELFPRV(lmp) = calloc(sizeof (Rt_elfp), 1)) == 0) { 2112 free(lmp); 2113 return (0); 2114 } 2115 2116 /* 2117 * All fields not filled in were set to 0 by calloc. 2118 */ 2119 ORIGNAME(lmp) = PATHNAME(lmp) = NAME(lmp) = (char *)pname; 2120 DYN(lmp) = ld; 2121 ADDR(lmp) = addr; 2122 MSIZE(lmp) = msize; 2123 ENTRY(lmp) = (Addr)entry; 2124 SYMINTP(lmp) = elf_find_sym; 2125 ETEXT(lmp) = etext; 2126 FCT(lmp) = &elf_fct; 2127 LIST(lmp) = lml; 2128 PADSTART(lmp) = paddr; 2129 PADIMLEN(lmp) = padimsize; 2130 THREADID(lmp) = rt_thr_self(); 2131 OBJFLTRNDX(lmp) = FLTR_DISABLED; 2132 SORTVAL(lmp) = -1; 2133 2134 MMAPS(lmp) = mmaps; 2135 MMAPCNT(lmp) = mmapcnt; 2136 ASSERT(mmapcnt != 0); 2137 2138 /* 2139 * If this is a shared object, add the base address to each address. 2140 * if this is an executable, use address as is. 2141 */ 2142 if (ehdr->e_type == ET_EXEC) { 2143 base = 0; 2144 FLAGS(lmp) |= FLG_RT_FIXED; 2145 } else 2146 base = addr; 2147 2148 /* 2149 * Fill in rest of the link map entries with information from the file's 2150 * dynamic structure. 2151 */ 2152 if (ld) { 2153 uint_t dynndx = 0; 2154 Xword pltpadsz = 0; 2155 Rti_desc *rti; 2156 2157 /* CSTYLED */ 2158 for ( ; ld->d_tag != DT_NULL; ++ld, dynndx++) { 2159 switch ((Xword)ld->d_tag) { 2160 case DT_SYMTAB: 2161 SYMTAB(lmp) = (void *)(ld->d_un.d_ptr + base); 2162 break; 2163 case DT_SUNW_SYMTAB: 2164 SUNWSYMTAB(lmp) = 2165 (void *)(ld->d_un.d_ptr + base); 2166 break; 2167 case DT_SUNW_SYMSZ: 2168 SUNWSYMSZ(lmp) = ld->d_un.d_val; 2169 break; 2170 case DT_STRTAB: 2171 STRTAB(lmp) = (void *)(ld->d_un.d_ptr + base); 2172 break; 2173 case DT_SYMENT: 2174 SYMENT(lmp) = ld->d_un.d_val; 2175 break; 2176 case DT_FEATURE_1: 2177 ld->d_un.d_val |= DTF_1_PARINIT; 2178 if (ld->d_un.d_val & DTF_1_CONFEXP) 2179 crle = 1; 2180 break; 2181 case DT_MOVESZ: 2182 MOVESZ(lmp) = ld->d_un.d_val; 2183 FLAGS(lmp) |= FLG_RT_MOVE; 2184 break; 2185 case DT_MOVEENT: 2186 MOVEENT(lmp) = ld->d_un.d_val; 2187 break; 2188 case DT_MOVETAB: 2189 MOVETAB(lmp) = (void *)(ld->d_un.d_ptr + base); 2190 break; 2191 case DT_REL: 2192 case DT_RELA: 2193 /* 2194 * At this time, ld.so. can only handle one 2195 * type of relocation per object. 2196 */ 2197 REL(lmp) = (void *)(ld->d_un.d_ptr + base); 2198 break; 2199 case DT_RELSZ: 2200 case DT_RELASZ: 2201 RELSZ(lmp) = ld->d_un.d_val; 2202 break; 2203 case DT_RELENT: 2204 case DT_RELAENT: 2205 RELENT(lmp) = ld->d_un.d_val; 2206 break; 2207 case DT_RELCOUNT: 2208 case DT_RELACOUNT: 2209 RELACOUNT(lmp) = (uint_t)ld->d_un.d_val; 2210 break; 2211 case DT_TEXTREL: 2212 FLAGS1(lmp) |= FL1_RT_TEXTREL; 2213 break; 2214 case DT_HASH: 2215 HASH(lmp) = (uint_t *)(ld->d_un.d_ptr + base); 2216 break; 2217 case DT_PLTGOT: 2218 PLTGOT(lmp) = (uint_t *)(ld->d_un.d_ptr + base); 2219 break; 2220 case DT_PLTRELSZ: 2221 PLTRELSZ(lmp) = ld->d_un.d_val; 2222 break; 2223 case DT_JMPREL: 2224 JMPREL(lmp) = (void *)(ld->d_un.d_ptr + base); 2225 break; 2226 case DT_INIT: 2227 if (ld->d_un.d_ptr != NULL) 2228 INIT(lmp) = 2229 (void (*)())(ld->d_un.d_ptr + base); 2230 break; 2231 case DT_FINI: 2232 if (ld->d_un.d_ptr != NULL) 2233 FINI(lmp) = 2234 (void (*)())(ld->d_un.d_ptr + base); 2235 break; 2236 case DT_INIT_ARRAY: 2237 INITARRAY(lmp) = (Addr *)(ld->d_un.d_ptr + 2238 base); 2239 break; 2240 case DT_INIT_ARRAYSZ: 2241 INITARRAYSZ(lmp) = (uint_t)ld->d_un.d_val; 2242 break; 2243 case DT_FINI_ARRAY: 2244 FINIARRAY(lmp) = (Addr *)(ld->d_un.d_ptr + 2245 base); 2246 break; 2247 case DT_FINI_ARRAYSZ: 2248 FINIARRAYSZ(lmp) = (uint_t)ld->d_un.d_val; 2249 break; 2250 case DT_PREINIT_ARRAY: 2251 PREINITARRAY(lmp) = (Addr *)(ld->d_un.d_ptr + 2252 base); 2253 break; 2254 case DT_PREINIT_ARRAYSZ: 2255 PREINITARRAYSZ(lmp) = (uint_t)ld->d_un.d_val; 2256 break; 2257 case DT_RPATH: 2258 case DT_RUNPATH: 2259 rpath = ld->d_un.d_val; 2260 break; 2261 case DT_FILTER: 2262 fltr = ld->d_un.d_val; 2263 OBJFLTRNDX(lmp) = dynndx; 2264 FLAGS1(lmp) |= FL1_RT_OBJSFLTR; 2265 break; 2266 case DT_AUXILIARY: 2267 if (!(rtld_flags & RT_FL_NOAUXFLTR)) { 2268 fltr = ld->d_un.d_val; 2269 OBJFLTRNDX(lmp) = dynndx; 2270 } 2271 FLAGS1(lmp) |= FL1_RT_OBJAFLTR; 2272 break; 2273 case DT_SUNW_FILTER: 2274 SYMSFLTRCNT(lmp)++; 2275 FLAGS1(lmp) |= FL1_RT_SYMSFLTR; 2276 break; 2277 case DT_SUNW_AUXILIARY: 2278 if (!(rtld_flags & RT_FL_NOAUXFLTR)) { 2279 SYMAFLTRCNT(lmp)++; 2280 } 2281 FLAGS1(lmp) |= FL1_RT_SYMAFLTR; 2282 break; 2283 case DT_DEPAUDIT: 2284 if (!(rtld_flags & RT_FL_NOAUDIT)) 2285 audit = ld->d_un.d_val; 2286 break; 2287 case DT_CONFIG: 2288 cfile = ld->d_un.d_val; 2289 break; 2290 case DT_DEBUG: 2291 /* 2292 * DT_DEBUG entries are only created in 2293 * dynamic objects that require an interpretor 2294 * (ie. all dynamic executables and some shared 2295 * objects), and provide for a hand-shake with 2296 * debuggers. This entry is initialized to 2297 * zero by the link-editor. If a debugger has 2298 * us and updated this entry set the debugger 2299 * flag, and finish initializing the debugging 2300 * structure (see setup() also). Switch off any 2301 * configuration object use as most debuggers 2302 * can't handle fixed dynamic executables as 2303 * dependencies, and we can't handle requests 2304 * like object padding for alternative objects. 2305 */ 2306 if (ld->d_un.d_ptr) 2307 rtld_flags |= 2308 (RT_FL_DEBUGGER | RT_FL_NOOBJALT); 2309 ld->d_un.d_ptr = (Addr)&r_debug; 2310 break; 2311 case DT_VERNEED: 2312 VERNEED(lmp) = (Verneed *)(ld->d_un.d_ptr + 2313 base); 2314 break; 2315 case DT_VERNEEDNUM: 2316 /* LINTED */ 2317 VERNEEDNUM(lmp) = (int)ld->d_un.d_val; 2318 break; 2319 case DT_VERDEF: 2320 VERDEF(lmp) = (Verdef *)(ld->d_un.d_ptr + base); 2321 break; 2322 case DT_VERDEFNUM: 2323 /* LINTED */ 2324 VERDEFNUM(lmp) = (int)ld->d_un.d_val; 2325 break; 2326 case DT_VERSYM: 2327 /* 2328 * The Solaris ld does not produce DT_VERSYM, 2329 * but the GNU ld does, in order to support 2330 * their style of versioning, which differs 2331 * from ours in some ways, while using the 2332 * same data structures. The presence of 2333 * DT_VERSYM therefore means that GNU 2334 * versioning rules apply to the given file. 2335 * If DT_VERSYM is not present, then Solaris 2336 * versioning rules apply. 2337 */ 2338 VERSYM(lmp) = (Versym *)(ld->d_un.d_ptr + base); 2339 break; 2340 case DT_BIND_NOW: 2341 if ((rtld_flags2 & RT_FL2_BINDLAZY) == 0) { 2342 MODE(lmp) |= RTLD_NOW; 2343 MODE(lmp) &= ~RTLD_LAZY; 2344 } 2345 break; 2346 case DT_FLAGS: 2347 FLAGS2(lmp) |= FL2_RT_DTFLAGS; 2348 if (ld->d_un.d_val & DF_SYMBOLIC) 2349 FLAGS1(lmp) |= FL1_RT_SYMBOLIC; 2350 if (ld->d_un.d_val & DF_TEXTREL) 2351 FLAGS1(lmp) |= FL1_RT_TEXTREL; 2352 if ((ld->d_un.d_val & DF_BIND_NOW) && 2353 ((rtld_flags2 & RT_FL2_BINDLAZY) == 0)) { 2354 MODE(lmp) |= RTLD_NOW; 2355 MODE(lmp) &= ~RTLD_LAZY; 2356 } 2357 /* 2358 * Capture any static TLS use, and enforce that 2359 * this object be non-deletable. 2360 */ 2361 if (ld->d_un.d_val & DF_STATIC_TLS) { 2362 FLAGS1(lmp) |= FL1_RT_TLSSTAT; 2363 MODE(lmp) |= RTLD_NODELETE; 2364 } 2365 break; 2366 case DT_FLAGS_1: 2367 if (ld->d_un.d_val & DF_1_DISPRELPND) 2368 FLAGS1(lmp) |= FL1_RT_DISPREL; 2369 if (ld->d_un.d_val & DF_1_GROUP) 2370 FLAGS(lmp) |= 2371 (FLG_RT_SETGROUP | FLG_RT_HANDLE); 2372 if ((ld->d_un.d_val & DF_1_NOW) && 2373 ((rtld_flags2 & RT_FL2_BINDLAZY) == 0)) { 2374 MODE(lmp) |= RTLD_NOW; 2375 MODE(lmp) &= ~RTLD_LAZY; 2376 } 2377 if (ld->d_un.d_val & DF_1_NODELETE) 2378 MODE(lmp) |= RTLD_NODELETE; 2379 if (ld->d_un.d_val & DF_1_INITFIRST) 2380 FLAGS(lmp) |= FLG_RT_INITFRST; 2381 if (ld->d_un.d_val & DF_1_NOOPEN) 2382 FLAGS(lmp) |= FLG_RT_NOOPEN; 2383 if (ld->d_un.d_val & DF_1_LOADFLTR) 2384 FLAGS(lmp) |= FLG_RT_LOADFLTR; 2385 if (ld->d_un.d_val & DF_1_NODUMP) 2386 FLAGS(lmp) |= FLG_RT_NODUMP; 2387 if (ld->d_un.d_val & DF_1_CONFALT) 2388 crle = 1; 2389 if (ld->d_un.d_val & DF_1_DIRECT) 2390 FLAGS1(lmp) |= FL1_RT_DIRECT; 2391 if (ld->d_un.d_val & DF_1_NODEFLIB) 2392 FLAGS1(lmp) |= FL1_RT_NODEFLIB; 2393 if (ld->d_un.d_val & DF_1_ENDFILTEE) 2394 FLAGS1(lmp) |= FL1_RT_ENDFILTE; 2395 if (ld->d_un.d_val & DF_1_TRANS) 2396 FLAGS(lmp) |= FLG_RT_TRANS; 2397 #ifndef EXPAND_RELATIVE 2398 if (ld->d_un.d_val & DF_1_ORIGIN) 2399 FLAGS1(lmp) |= FL1_RT_RELATIVE; 2400 #endif 2401 /* 2402 * Global auditing is only meaningful when 2403 * specified by the initiating object of the 2404 * process - typically the dynamic executable. 2405 * If this is the initiaiting object, its link- 2406 * map will not yet have been added to the 2407 * link-map list, and consequently the link-map 2408 * list is empty. (see setup()). 2409 */ 2410 if (ld->d_un.d_val & DF_1_GLOBAUDIT) { 2411 if (lml_main.lm_head == 0) 2412 FLAGS1(lmp) |= FL1_RT_GLOBAUD; 2413 else 2414 DBG_CALL(Dbg_audit_ignore(lmp)); 2415 } 2416 2417 /* 2418 * If this object identifies itself as an 2419 * interposer, but relocation processing has 2420 * already started, then demote it. It's too 2421 * late to guarantee complete interposition. 2422 */ 2423 /* BEGIN CSTYLED */ 2424 if (ld->d_un.d_val & 2425 (DF_1_INTERPOSE | DF_1_SYMINTPOSE)) { 2426 if (lml->lm_flags & LML_FLG_STARTREL) { 2427 DBG_CALL(Dbg_util_intoolate(lmp)); 2428 if (lml->lm_flags & LML_FLG_TRC_ENABLE) 2429 (void) printf( 2430 MSG_INTL(MSG_LDD_REL_ERR2), 2431 NAME(lmp)); 2432 } else if (ld->d_un.d_val & DF_1_INTERPOSE) 2433 FLAGS(lmp) |= FLG_RT_OBJINTPO; 2434 else 2435 FLAGS(lmp) |= FLG_RT_SYMINTPO; 2436 } 2437 /* END CSTYLED */ 2438 break; 2439 case DT_SYMINFO: 2440 SYMINFO(lmp) = (Syminfo *)(ld->d_un.d_ptr + 2441 base); 2442 break; 2443 case DT_SYMINENT: 2444 SYMINENT(lmp) = ld->d_un.d_val; 2445 break; 2446 case DT_PLTPAD: 2447 PLTPAD(lmp) = (void *)(ld->d_un.d_ptr + base); 2448 break; 2449 case DT_PLTPADSZ: 2450 pltpadsz = ld->d_un.d_val; 2451 break; 2452 case DT_SUNW_RTLDINF: 2453 /* 2454 * Maintain a list of RTLDINFO structures. 2455 * Typically, libc is the only supplier, and 2456 * only one structure is provided. However, 2457 * multiple suppliers and multiple structures 2458 * are supported. For example, one structure 2459 * may provide thread_init, and another 2460 * structure may provide atexit reservations. 2461 */ 2462 if ((rti = alist_append(&lml->lm_rti, 0, 2463 sizeof (Rti_desc), AL_CNT_RTLDINFO)) == 0) { 2464 remove_so(0, lmp); 2465 return (0); 2466 } 2467 rti->rti_lmp = lmp; 2468 rti->rti_info = (void *)(ld->d_un.d_ptr + base); 2469 break; 2470 case DT_SUNW_SORTENT: 2471 SUNWSORTENT(lmp) = ld->d_un.d_val; 2472 break; 2473 case DT_SUNW_SYMSORT: 2474 SUNWSYMSORT(lmp) = 2475 (void *)(ld->d_un.d_ptr + base); 2476 break; 2477 case DT_SUNW_SYMSORTSZ: 2478 SUNWSYMSORTSZ(lmp) = ld->d_un.d_val; 2479 break; 2480 case DT_DEPRECATED_SPARC_REGISTER: 2481 case M_DT_REGISTER: 2482 FLAGS(lmp) |= FLG_RT_REGSYMS; 2483 break; 2484 } 2485 } 2486 2487 if (PLTPAD(lmp)) { 2488 if (pltpadsz == (Xword)0) 2489 PLTPAD(lmp) = 0; 2490 else 2491 PLTPADEND(lmp) = (void *)((Addr)PLTPAD(lmp) + 2492 pltpadsz); 2493 } 2494 2495 /* 2496 * Allocate a Dynamic Info structure. 2497 */ 2498 if ((DYNINFO(lmp) = calloc((size_t)dynndx, 2499 sizeof (Dyninfo))) == 0) { 2500 remove_so(0, lmp); 2501 return (0); 2502 } 2503 DYNINFOCNT(lmp) = dynndx; 2504 } 2505 2506 /* 2507 * A dynsym contains only global functions. We want to have 2508 * a version of it that also includes local functions, so that 2509 * dladdr() will be able to report names for local functions 2510 * when used to generate a stack trace for a stripped file. 2511 * This version of the dynsym is provided via DT_SUNW_SYMTAB. 2512 * 2513 * In producing DT_SUNW_SYMTAB, ld uses a non-obvious trick 2514 * in order to avoid having to have two copies of the global 2515 * symbols held in DT_SYMTAB: The local symbols are placed in 2516 * a separate section than the globals in the dynsym, but the 2517 * linker conspires to put the data for these two sections adjacent 2518 * to each other. DT_SUNW_SYMTAB points at the top of the local 2519 * symbols, and DT_SUNW_SYMSZ is the combined length of both tables. 2520 * 2521 * If the two sections are not adjacent, then something went wrong 2522 * at link time. We use ASSERT to kill the process if this is 2523 * a debug build. In a production build, we will silently ignore 2524 * the presence of the .ldynsym and proceed. We can detect this 2525 * situation by checking to see that DT_SYMTAB lies in 2526 * the range given by DT_SUNW_SYMTAB/DT_SUNW_SYMSZ. 2527 */ 2528 if ((SUNWSYMTAB(lmp) != NULL) && 2529 (((char *)SYMTAB(lmp) <= (char *)SUNWSYMTAB(lmp)) || 2530 (((char *)SYMTAB(lmp) >= 2531 (SUNWSYMSZ(lmp) + (char *)SUNWSYMTAB(lmp)))))) { 2532 ASSERT(0); 2533 SUNWSYMTAB(lmp) = NULL; 2534 SUNWSYMSZ(lmp) = 0; 2535 } 2536 2537 /* 2538 * If configuration file use hasn't been disabled, and a configuration 2539 * file hasn't already been set via an environment variable, see if any 2540 * application specific configuration file is specified. An LD_CONFIG 2541 * setting is used first, but if this image was generated via crle(1) 2542 * then a default configuration file is a fall-back. 2543 */ 2544 if ((!(rtld_flags & RT_FL_NOCFG)) && (config->c_name == 0)) { 2545 if (cfile) 2546 config->c_name = (const char *)(cfile + 2547 (char *)STRTAB(lmp)); 2548 else if (crle) { 2549 rtld_flags |= RT_FL_CONFAPP; 2550 #ifndef EXPAND_RELATIVE 2551 FLAGS1(lmp) |= FL1_RT_RELATIVE; 2552 #endif 2553 } 2554 } 2555 2556 if (rpath) 2557 RPATH(lmp) = (char *)(rpath + (char *)STRTAB(lmp)); 2558 if (fltr) { 2559 /* 2560 * If this object is a global filter, duplicate the filtee 2561 * string name(s) so that REFNAME() is available in core files. 2562 * This cludge was useful for debuggers at one point, but only 2563 * when the filtee name was an individual full path. 2564 */ 2565 if ((REFNAME(lmp) = strdup(fltr + (char *)STRTAB(lmp))) == 0) { 2566 remove_so(0, lmp); 2567 return (0); 2568 } 2569 } 2570 2571 if (rtld_flags & RT_FL_RELATIVE) 2572 FLAGS1(lmp) |= FL1_RT_RELATIVE; 2573 2574 /* 2575 * For Intel ABI compatibility. It's possible that a JMPREL can be 2576 * specified without any other relocations (e.g. a dynamic executable 2577 * normally only contains .plt relocations). If this is the case then 2578 * no REL, RELSZ or RELENT will have been created. For us to be able 2579 * to traverse the .plt relocations under LD_BIND_NOW we need to know 2580 * the RELENT for these relocations. Refer to elf_reloc() for more 2581 * details. 2582 */ 2583 if (!RELENT(lmp) && JMPREL(lmp)) 2584 RELENT(lmp) = sizeof (Rel); 2585 2586 /* 2587 * Establish any per-object auditing. If we're establishing `main's 2588 * link-map its too early to go searching for audit objects so just 2589 * hold the object name for later (see setup()). 2590 */ 2591 if (audit) { 2592 char *cp = audit + (char *)STRTAB(lmp); 2593 2594 if (*cp) { 2595 if (((AUDITORS(lmp) = 2596 calloc(1, sizeof (Audit_desc))) == 0) || 2597 ((AUDITORS(lmp)->ad_name = strdup(cp)) == 0)) { 2598 remove_so(0, lmp); 2599 return (0); 2600 } 2601 if (lml_main.lm_head) { 2602 if (audit_setup(lmp, AUDITORS(lmp), 0, 2603 in_nfavl) == 0) { 2604 remove_so(0, lmp); 2605 return (0); 2606 } 2607 FLAGS1(lmp) |= AUDITORS(lmp)->ad_flags; 2608 lml->lm_flags |= LML_FLG_LOCAUDIT; 2609 } 2610 } 2611 } 2612 2613 if ((CONDVAR(lmp) = rt_cond_create()) == 0) { 2614 remove_so(0, lmp); 2615 return (0); 2616 } 2617 if (oname && ((append_alias(lmp, oname, 0)) == 0)) { 2618 remove_so(0, lmp); 2619 return (0); 2620 } 2621 2622 /* 2623 * Add the mapped object to the end of the link map list. 2624 */ 2625 lm_append(lml, lmco, lmp); 2626 return (lmp); 2627 } 2628 2629 /* 2630 * Assign hardware/software capabilities. 2631 */ 2632 void 2633 cap_assign(Cap *cap, Rt_map *lmp) 2634 { 2635 while (cap->c_tag != CA_SUNW_NULL) { 2636 switch (cap->c_tag) { 2637 case CA_SUNW_HW_1: 2638 HWCAP(lmp) = cap->c_un.c_val; 2639 break; 2640 case CA_SUNW_SF_1: 2641 SFCAP(lmp) = cap->c_un.c_val; 2642 } 2643 cap++; 2644 } 2645 } 2646 2647 /* 2648 * Map in an ELF object. 2649 * Takes an open file descriptor for the object to map and its pathname; returns 2650 * a pointer to a Rt_map structure for this object, or 0 on error. 2651 */ 2652 static Rt_map * 2653 elf_map_so(Lm_list *lml, Aliste lmco, const char *pname, const char *oname, 2654 int fd, int *in_nfavl) 2655 { 2656 int i; /* general temporary */ 2657 Off memsize = 0; /* total memory size of pathname */ 2658 Off mentry; /* entry point */ 2659 Ehdr *ehdr; /* ELF header of ld.so */ 2660 Phdr *phdr; /* first Phdr in file */ 2661 Phdr *phdr0; /* Saved first Phdr in file */ 2662 Phdr *pptr; /* working Phdr */ 2663 Phdr *fph = 0; /* first loadable Phdr */ 2664 Phdr *lph; /* last loadable Phdr */ 2665 Phdr *lfph = 0; /* last loadable (filesz != 0) Phdr */ 2666 Phdr *lmph = 0; /* last loadable (memsz != 0) Phdr */ 2667 Phdr *tlph = 0; /* program header for PT_TLS */ 2668 Phdr *unwindph = 0; /* program header for PT_SUNW_UNWIND */ 2669 Cap *cap = 0; /* program header for SUNWCAP */ 2670 Dyn *mld = 0; /* DYNAMIC structure for pathname */ 2671 size_t size; /* size of elf and program headers */ 2672 caddr_t faddr = 0; /* mapping address of pathname */ 2673 Rt_map *lmp; /* link map created */ 2674 caddr_t paddr; /* start of padded image */ 2675 Off plen; /* size of image including padding */ 2676 Half etype; 2677 int fixed; 2678 Mmap *mmaps; 2679 uint_t mmapcnt = 0; 2680 Xword align = 0; 2681 2682 /* LINTED */ 2683 ehdr = (Ehdr *)fmap->fm_maddr; 2684 2685 /* 2686 * If this a relocatable object then special processing is required. 2687 */ 2688 if ((etype = ehdr->e_type) == ET_REL) 2689 return (elf_obj_file(lml, lmco, pname, fd)); 2690 2691 /* 2692 * If this isn't a dynamic executable or shared object we can't process 2693 * it. If this is a dynamic executable then all addresses are fixed. 2694 */ 2695 if (etype == ET_EXEC) { 2696 fixed = 1; 2697 } else if (etype == ET_DYN) { 2698 fixed = 0; 2699 } else { 2700 Conv_inv_buf_t inv_buf; 2701 2702 eprintf(lml, ERR_ELF, MSG_INTL(MSG_GEN_BADTYPE), pname, 2703 conv_ehdr_type(etype, 0, &inv_buf)); 2704 return (0); 2705 } 2706 2707 /* 2708 * If our original mapped page was not large enough to hold all the 2709 * program headers remap them. 2710 */ 2711 size = (size_t)((char *)ehdr->e_phoff + 2712 (ehdr->e_phnum * ehdr->e_phentsize)); 2713 if (size > fmap->fm_fsize) { 2714 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_GEN_CORTRUNC), pname); 2715 return (0); 2716 } 2717 if (size > fmap->fm_msize) { 2718 fmap_setup(); 2719 if ((fmap->fm_maddr = mmap(fmap->fm_maddr, size, PROT_READ, 2720 fmap->fm_mflags, fd, 0)) == MAP_FAILED) { 2721 int err = errno; 2722 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_SYS_MMAP), pname, 2723 strerror(err)); 2724 return (0); 2725 } 2726 fmap->fm_msize = size; 2727 /* LINTED */ 2728 ehdr = (Ehdr *)fmap->fm_maddr; 2729 } 2730 /* LINTED */ 2731 phdr0 = phdr = (Phdr *)((char *)ehdr + ehdr->e_ehsize); 2732 2733 /* 2734 * Get entry point. 2735 */ 2736 mentry = ehdr->e_entry; 2737 2738 /* 2739 * Point at program headers and perform some basic validation. 2740 */ 2741 for (i = 0, pptr = phdr; i < (int)ehdr->e_phnum; i++, 2742 pptr = (Phdr *)((Off)pptr + ehdr->e_phentsize)) { 2743 if (pptr->p_type == PT_LOAD) { 2744 2745 if (fph == 0) { 2746 fph = pptr; 2747 /* LINTED argument lph is initialized in first pass */ 2748 } else if (pptr->p_vaddr <= lph->p_vaddr) { 2749 eprintf(lml, ERR_ELF, 2750 MSG_INTL(MSG_GEN_INVPRGHDR), pname); 2751 return (0); 2752 } 2753 2754 lph = pptr; 2755 2756 if (pptr->p_memsz) 2757 lmph = pptr; 2758 if (pptr->p_filesz) 2759 lfph = pptr; 2760 if (pptr->p_align > align) 2761 align = pptr->p_align; 2762 2763 } else if (pptr->p_type == PT_DYNAMIC) { 2764 mld = (Dyn *)(pptr->p_vaddr); 2765 } else if ((pptr->p_type == PT_TLS) && pptr->p_memsz) { 2766 tlph = pptr; 2767 } else if (pptr->p_type == PT_SUNWCAP) { 2768 cap = (Cap *)(pptr->p_vaddr); 2769 } else if (pptr->p_type == PT_SUNW_UNWIND) { 2770 unwindph = pptr; 2771 } 2772 } 2773 2774 #if defined(MAP_ALIGN) 2775 /* 2776 * Make sure the maximum page alignment is a power of 2 >= the default 2777 * segment alignment, for use with MAP_ALIGN. 2778 */ 2779 align = S_ROUND(align, M_SEGM_ALIGN); 2780 #endif 2781 2782 /* 2783 * We'd better have at least one loadable segment, together with some 2784 * specified file and memory size. 2785 */ 2786 if ((fph == 0) || (lmph == 0) || (lfph == 0)) { 2787 eprintf(lml, ERR_ELF, MSG_INTL(MSG_GEN_NOLOADSEG), pname); 2788 return (0); 2789 } 2790 2791 /* 2792 * Check that the files size accounts for the loadable sections 2793 * we're going to map in (failure to do this may cause spurious 2794 * bus errors if we're given a truncated file). 2795 */ 2796 if (fmap->fm_fsize < ((size_t)lfph->p_offset + lfph->p_filesz)) { 2797 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_GEN_CORTRUNC), pname); 2798 return (0); 2799 } 2800 2801 /* 2802 * Memsize must be page rounded so that if we add object padding 2803 * at the end it will start at the beginning of a page. 2804 */ 2805 plen = memsize = M_PROUND((lmph->p_vaddr + lmph->p_memsz) - 2806 M_PTRUNC((ulong_t)fph->p_vaddr)); 2807 2808 /* 2809 * Determine if an existing mapping is acceptable. 2810 */ 2811 if (interp && (lml->lm_flags & LML_FLG_BASELM) && 2812 (strcmp(pname, interp->i_name) == 0)) { 2813 /* 2814 * If this is the interpreter then it has already been mapped 2815 * and we have the address so don't map it again. Note that 2816 * the common occurrence of a reference to the interpretor 2817 * (libdl -> ld.so.1) will have been caught during filter 2818 * initialization (see elf_lookup_filtee()). However, some 2819 * ELF implementations are known to record libc.so.1 as the 2820 * interpretor, and thus this test catches this behavior. 2821 */ 2822 paddr = faddr = interp->i_faddr; 2823 2824 } else if ((fixed == 0) && (r_debug.rtd_objpad == 0) && 2825 (memsize <= fmap->fm_msize) && ((fph->p_flags & PF_W) == 0) && 2826 (fph == lph) && (fph->p_filesz == fph->p_memsz) && 2827 (((Xword)fmap->fm_maddr % align) == 0)) { 2828 size_t rsize; 2829 2830 /* 2831 * If the file contains a single segment, and the mapping 2832 * required has already been established from the initial fmap 2833 * mapping, then we don't need to do anything more. Reset the 2834 * fmap address so that any later files start a new fmap. This 2835 * is really an optimization for filters, such as libdl.so, 2836 * libthread, etc. that are constructed to be a single text 2837 * segment. 2838 */ 2839 paddr = faddr = fmap->fm_maddr; 2840 2841 /* 2842 * Free any unused mapping by assigning the fmap buffer to the 2843 * unused region. fmap_setup() will unmap this area and 2844 * establish defaults for future mappings. 2845 */ 2846 rsize = M_PROUND(fph->p_filesz); 2847 fmap->fm_maddr += rsize; 2848 fmap->fm_msize -= rsize; 2849 fmap_setup(); 2850 } 2851 2852 /* 2853 * Allocate a mapping array to retain mapped segment information. 2854 */ 2855 if ((mmaps = calloc(ehdr->e_phnum, sizeof (Mmap))) == 0) 2856 return (0); 2857 2858 /* 2859 * If we're reusing an existing mapping determine the objects etext 2860 * address. Otherwise map the file (which will calculate the etext 2861 * address as part of the mapping process). 2862 */ 2863 if (faddr) { 2864 caddr_t base; 2865 2866 if (fixed) 2867 base = 0; 2868 else 2869 base = faddr; 2870 2871 /* LINTED */ 2872 phdr0 = phdr = (Phdr *)((char *)faddr + ehdr->e_ehsize); 2873 2874 for (i = 0, pptr = phdr; i < (int)ehdr->e_phnum; i++, 2875 pptr = (Phdr *)((Off)pptr + ehdr->e_phentsize)) { 2876 if (pptr->p_type != PT_LOAD) 2877 continue; 2878 2879 mmaps[mmapcnt].m_vaddr = (pptr->p_vaddr + base); 2880 mmaps[mmapcnt].m_msize = pptr->p_memsz; 2881 mmaps[mmapcnt].m_fsize = pptr->p_filesz; 2882 mmaps[mmapcnt].m_perm = (PROT_READ | PROT_EXEC); 2883 mmapcnt++; 2884 2885 if (!(pptr->p_flags & PF_W)) { 2886 fmap->fm_etext = (ulong_t)pptr->p_vaddr + 2887 (ulong_t)pptr->p_memsz + 2888 (ulong_t)(fixed ? 0 : faddr); 2889 } 2890 } 2891 } else { 2892 /* 2893 * Map the file. 2894 */ 2895 if (!(faddr = elf_map_it(lml, pname, memsize, ehdr, fph, lph, 2896 &phdr, &paddr, &plen, fixed, fd, align, mmaps, &mmapcnt))) 2897 return (0); 2898 } 2899 2900 /* 2901 * Calculate absolute base addresses and entry points. 2902 */ 2903 if (!fixed) { 2904 if (mld) 2905 /* LINTED */ 2906 mld = (Dyn *)((Off)mld + faddr); 2907 if (cap) 2908 /* LINTED */ 2909 cap = (Cap *)((Off)cap + faddr); 2910 mentry += (Off)faddr; 2911 } 2912 2913 /* 2914 * Create new link map structure for newly mapped shared object. 2915 */ 2916 if (!(lmp = elf_new_lm(lml, pname, oname, mld, (ulong_t)faddr, 2917 fmap->fm_etext, lmco, memsize, mentry, (ulong_t)paddr, plen, mmaps, 2918 mmapcnt, in_nfavl))) { 2919 (void) munmap((caddr_t)faddr, memsize); 2920 return (0); 2921 } 2922 2923 /* 2924 * Start the system loading in the ELF information we'll be processing. 2925 */ 2926 if (REL(lmp)) { 2927 (void) madvise((void *)ADDR(lmp), (uintptr_t)REL(lmp) + 2928 (uintptr_t)RELSZ(lmp) - (uintptr_t)ADDR(lmp), 2929 MADV_WILLNEED); 2930 } 2931 2932 /* 2933 * If this shared object contains any special segments, record them. 2934 */ 2935 if (tlph && (tls_assign(lml, lmp, (phdr + (tlph - phdr0))) == 0)) { 2936 remove_so(lml, lmp); 2937 return (0); 2938 } 2939 2940 if (unwindph) 2941 PTUNWIND(lmp) = phdr + (unwindph - phdr0); 2942 2943 if (cap) 2944 cap_assign(cap, lmp); 2945 2946 return (lmp); 2947 } 2948 2949 /* 2950 * Function to correct protection settings. Segments are all mapped initially 2951 * with permissions as given in the segment header. We need to turn on write 2952 * permissions on a text segment if there are any relocations against that 2953 * segment, and them turn write permission back off again before returning 2954 * control to the user. This function turns the permission on or off depending 2955 * on the value of the argument. 2956 */ 2957 int 2958 elf_set_prot(Rt_map *lmp, int permission) 2959 { 2960 Mmap *mmaps; 2961 2962 /* 2963 * If this is an allocated image (ie. a relocatable object) we can't 2964 * mprotect() anything. 2965 */ 2966 if (FLAGS(lmp) & FLG_RT_IMGALLOC) 2967 return (1); 2968 2969 DBG_CALL(Dbg_file_prot(lmp, permission)); 2970 2971 for (mmaps = MMAPS(lmp); mmaps->m_vaddr; mmaps++) { 2972 if (mmaps->m_perm & PROT_WRITE) 2973 continue; 2974 2975 if (mprotect(mmaps->m_vaddr, mmaps->m_msize, 2976 (mmaps->m_perm | permission)) == -1) { 2977 int err = errno; 2978 eprintf(LIST(lmp), ERR_FATAL, MSG_INTL(MSG_SYS_MPROT), 2979 NAME(lmp), strerror(err)); 2980 return (0); 2981 } 2982 } 2983 return (1); 2984 } 2985 2986 /* 2987 * Build full pathname of shared object from given directory name and filename. 2988 */ 2989 static char * 2990 elf_get_so(const char *dir, const char *file) 2991 { 2992 static char pname[PATH_MAX]; 2993 2994 (void) snprintf(pname, PATH_MAX, MSG_ORIG(MSG_FMT_PATH), dir, file); 2995 return (pname); 2996 } 2997 2998 /* 2999 * The copy relocation is recorded in a copy structure which will be applied 3000 * after all other relocations are carried out. This provides for copying data 3001 * that must be relocated itself (ie. pointers in shared objects). This 3002 * structure also provides a means of binding RTLD_GROUP dependencies to any 3003 * copy relocations that have been taken from any group members. 3004 * 3005 * If the size of the .bss area available for the copy information is not the 3006 * same as the source of the data inform the user if we're under ldd(1) control 3007 * (this checking was only established in 5.3, so by only issuing an error via 3008 * ldd(1) we maintain the standard set by previous releases). 3009 */ 3010 int 3011 elf_copy_reloc(char *name, Sym *rsym, Rt_map *rlmp, void *radd, Sym *dsym, 3012 Rt_map *dlmp, const void *dadd) 3013 { 3014 Rel_copy rc; 3015 Lm_list *lml = LIST(rlmp); 3016 3017 rc.r_name = name; 3018 rc.r_rsym = rsym; /* the new reference symbol and its */ 3019 rc.r_rlmp = rlmp; /* associated link-map */ 3020 rc.r_dlmp = dlmp; /* the defining link-map */ 3021 rc.r_dsym = dsym; /* the original definition */ 3022 rc.r_radd = radd; 3023 rc.r_dadd = dadd; 3024 3025 if (rsym->st_size > dsym->st_size) 3026 rc.r_size = (size_t)dsym->st_size; 3027 else 3028 rc.r_size = (size_t)rsym->st_size; 3029 3030 if (alist_append(©_R(dlmp), &rc, sizeof (Rel_copy), 3031 AL_CNT_COPYREL) == 0) { 3032 if (!(lml->lm_flags & LML_FLG_TRC_WARN)) 3033 return (0); 3034 else 3035 return (1); 3036 } 3037 if (!(FLAGS1(dlmp) & FL1_RT_COPYTOOK)) { 3038 if (aplist_append(©_S(rlmp), dlmp, 3039 AL_CNT_COPYREL) == NULL) { 3040 if (!(lml->lm_flags & LML_FLG_TRC_WARN)) 3041 return (0); 3042 else 3043 return (1); 3044 } 3045 FLAGS1(dlmp) |= FL1_RT_COPYTOOK; 3046 } 3047 3048 /* 3049 * If we are tracing (ldd), warn the user if 3050 * 1) the size from the reference symbol differs from the 3051 * copy definition. We can only copy as much data as the 3052 * reference (dynamic executables) entry allows. 3053 * 2) the copy definition has STV_PROTECTED visibility. 3054 */ 3055 if (lml->lm_flags & LML_FLG_TRC_WARN) { 3056 if (rsym->st_size != dsym->st_size) { 3057 (void) printf(MSG_INTL(MSG_LDD_CPY_SIZDIF), 3058 _conv_reloc_type(M_R_COPY), demangle(name), 3059 NAME(rlmp), EC_XWORD(rsym->st_size), 3060 NAME(dlmp), EC_XWORD(dsym->st_size)); 3061 if (rsym->st_size > dsym->st_size) 3062 (void) printf(MSG_INTL(MSG_LDD_CPY_INSDATA), 3063 NAME(dlmp)); 3064 else 3065 (void) printf(MSG_INTL(MSG_LDD_CPY_DATRUNC), 3066 NAME(rlmp)); 3067 } 3068 3069 if (ELF_ST_VISIBILITY(dsym->st_other) == STV_PROTECTED) { 3070 (void) printf(MSG_INTL(MSG_LDD_CPY_PROT), 3071 _conv_reloc_type(M_R_COPY), demangle(name), 3072 NAME(dlmp)); 3073 } 3074 } 3075 3076 DBG_CALL(Dbg_reloc_apply_val(lml, ELF_DBG_RTLD, (Xword)radd, 3077 (Xword)rc.r_size)); 3078 return (1); 3079 } 3080 3081 /* 3082 * Determine the symbol location of an address within a link-map. Look for 3083 * the nearest symbol (whose value is less than or equal to the required 3084 * address). This is the object specific part of dladdr(). 3085 */ 3086 static void 3087 elf_dladdr(ulong_t addr, Rt_map *lmp, Dl_info *dlip, void **info, int flags) 3088 { 3089 ulong_t ndx, cnt, base, _value; 3090 Sym *sym, *_sym = NULL; 3091 const char *str; 3092 int _flags; 3093 uint_t *dynaddr_ndx; 3094 uint_t dynaddr_n = 0; 3095 ulong_t value; 3096 3097 /* 3098 * If SUNWSYMTAB() is non-NULL, then it sees a special version of 3099 * the dynsym that starts with any local function symbols that exist in 3100 * the library and then moves to the data held in SYMTAB(). In this 3101 * case, SUNWSYMSZ tells us how long the symbol table is. The 3102 * availability of local function symbols will enhance the results 3103 * we can provide. 3104 * 3105 * If SUNWSYMTAB() is non-NULL, then there might also be a 3106 * SUNWSYMSORT() vector associated with it. SUNWSYMSORT() contains 3107 * an array of indices into SUNWSYMTAB, sorted by increasing 3108 * address. We can use this to do an O(log N) search instead of a 3109 * brute force search. 3110 * 3111 * If SUNWSYMTAB() is NULL, then SYMTAB() references a dynsym that 3112 * contains only global symbols. In that case, the length of 3113 * the symbol table comes from the nchain field of the related 3114 * symbol lookup hash table. 3115 */ 3116 str = STRTAB(lmp); 3117 if (SUNWSYMSZ(lmp) == NULL) { 3118 sym = SYMTAB(lmp); 3119 /* 3120 * If we don't have a .hash table there are no symbols 3121 * to look at. 3122 */ 3123 if (HASH(lmp) == 0) 3124 return; 3125 cnt = HASH(lmp)[1]; 3126 } else { 3127 sym = SUNWSYMTAB(lmp); 3128 cnt = SUNWSYMSZ(lmp) / SYMENT(lmp); 3129 dynaddr_ndx = SUNWSYMSORT(lmp); 3130 if (dynaddr_ndx != NULL) 3131 dynaddr_n = SUNWSYMSORTSZ(lmp) / SUNWSORTENT(lmp); 3132 } 3133 3134 if (FLAGS(lmp) & FLG_RT_FIXED) 3135 base = 0; 3136 else 3137 base = ADDR(lmp); 3138 3139 if (dynaddr_n > 0) { /* Binary search */ 3140 long low = 0, low_bnd; 3141 long high = dynaddr_n - 1, high_bnd; 3142 long mid; 3143 Sym *mid_sym; 3144 3145 /* 3146 * Note that SUNWSYMSORT only contains symbols types that 3147 * supply memory addresses, so there's no need to check and 3148 * filter out any other types. 3149 */ 3150 low_bnd = low; 3151 high_bnd = high; 3152 while (low <= high) { 3153 mid = (low + high) / 2; 3154 mid_sym = &sym[dynaddr_ndx[mid]]; 3155 value = mid_sym->st_value + base; 3156 if (addr < value) { 3157 if ((sym[dynaddr_ndx[high]].st_value + base) >= 3158 addr) 3159 high_bnd = high; 3160 high = mid - 1; 3161 } else if (addr > value) { 3162 if ((sym[dynaddr_ndx[low]].st_value + base) <= 3163 addr) 3164 low_bnd = low; 3165 low = mid + 1; 3166 } else { 3167 _sym = mid_sym; 3168 _value = value; 3169 break; 3170 } 3171 } 3172 /* 3173 * If the above didn't find it exactly, then we must 3174 * return the closest symbol with a value that doesn't 3175 * exceed the one we are looking for. If that symbol exists, 3176 * it will lie in the range bounded by low_bnd and 3177 * high_bnd. This is a linear search, but a short one. 3178 */ 3179 if (_sym == NULL) { 3180 for (mid = low_bnd; mid <= high_bnd; mid++) { 3181 mid_sym = &sym[dynaddr_ndx[mid]]; 3182 value = mid_sym->st_value + base; 3183 if (addr >= value) { 3184 _sym = mid_sym; 3185 _value = value; 3186 } else { 3187 break; 3188 } 3189 } 3190 } 3191 } else { /* Linear search */ 3192 for (_value = 0, sym++, ndx = 1; ndx < cnt; ndx++, sym++) { 3193 /* 3194 * Skip expected symbol types that are not functions 3195 * or data: 3196 * - A symbol table starts with an undefined symbol 3197 * in slot 0. If we are using SUNWSYMTAB(), 3198 * there will be a second undefined symbol 3199 * right before the globals. 3200 * - The local part of SUNWSYMTAB() contains a 3201 * series of function symbols. Each section 3202 * starts with an initial STT_FILE symbol. 3203 */ 3204 if ((sym->st_shndx == SHN_UNDEF) || 3205 (ELF_ST_TYPE(sym->st_info) == STT_FILE)) 3206 continue; 3207 3208 value = sym->st_value + base; 3209 if (value > addr) 3210 continue; 3211 if (value < _value) 3212 continue; 3213 3214 _sym = sym; 3215 _value = value; 3216 3217 /* 3218 * Note, because we accept local and global symbols 3219 * we could find a section symbol that matches the 3220 * associated address, which means that the symbol 3221 * name will be null. In this case continue the 3222 * search in case we can find a global symbol of 3223 * the same value. 3224 */ 3225 if ((value == addr) && 3226 (ELF_ST_TYPE(sym->st_info) != STT_SECTION)) 3227 break; 3228 } 3229 } 3230 3231 _flags = flags & RTLD_DL_MASK; 3232 if (_sym) { 3233 if (_flags == RTLD_DL_SYMENT) 3234 *info = (void *)_sym; 3235 else if (_flags == RTLD_DL_LINKMAP) 3236 *info = (void *)lmp; 3237 3238 dlip->dli_sname = str + _sym->st_name; 3239 dlip->dli_saddr = (void *)_value; 3240 } else { 3241 /* 3242 * addr lies between the beginning of the mapped segment and 3243 * the first global symbol. We have no symbol to return 3244 * and the caller requires one. We use _START_, the base 3245 * address of the mapping. 3246 */ 3247 3248 if (_flags == RTLD_DL_SYMENT) { 3249 /* 3250 * An actual symbol struct is needed, so we 3251 * construct one for _START_. To do this in a 3252 * fully accurate way requires a different symbol 3253 * for each mapped segment. This requires the 3254 * use of dynamic memory and a mutex. That's too much 3255 * plumbing for a fringe case of limited importance. 3256 * 3257 * Fortunately, we can simplify: 3258 * - Only the st_size and st_info fields are useful 3259 * outside of the linker internals. The others 3260 * reference things that outside code cannot see, 3261 * and can be set to 0. 3262 * - It's just a label and there is no size 3263 * to report. So, the size should be 0. 3264 * This means that only st_info needs a non-zero 3265 * (constant) value. A static struct will suffice. 3266 * It must be const (readonly) so the caller can't 3267 * change its meaning for subsequent callers. 3268 */ 3269 static const Sym fsym = { 0, 0, 0, 3270 ELF_ST_INFO(STB_LOCAL, STT_OBJECT) }; 3271 *info = (void *) &fsym; 3272 } 3273 3274 dlip->dli_sname = MSG_ORIG(MSG_SYM_START); 3275 dlip->dli_saddr = (void *) ADDR(lmp); 3276 } 3277 } 3278 3279 static void 3280 elf_lazy_cleanup(APlist *alp) 3281 { 3282 Rt_map *lmp; 3283 Aliste idx; 3284 3285 /* 3286 * Cleanup any link-maps added to this dynamic list and free it. 3287 */ 3288 for (APLIST_TRAVERSE(alp, idx, lmp)) 3289 FLAGS(lmp) &= ~FLG_RT_TMPLIST; 3290 free(alp); 3291 } 3292 3293 /* 3294 * This routine is called as a last fall-back to search for a symbol from a 3295 * standard relocation. To maintain lazy loadings goal of reducing the number 3296 * of objects mapped, any symbol search is first carried out using the objects 3297 * that already exist in the process (either on a link-map list or handle). 3298 * If a symbol can't be found, and lazy dependencies are still pending, this 3299 * routine loads the dependencies in an attempt to locate the symbol. 3300 * 3301 * Only new objects are inspected as we will have already inspected presently 3302 * loaded objects before calling this routine. However, a new object may not 3303 * be new - although the di_lmp might be zero, the object may have been mapped 3304 * as someone elses dependency. Thus there's a possibility of some symbol 3305 * search duplication. 3306 */ 3307 Sym * 3308 elf_lazy_find_sym(Slookup *slp, Rt_map **_lmp, uint_t *binfo, int *in_nfavl) 3309 { 3310 Sym *sym = 0; 3311 APlist *alist = NULL; 3312 Aliste idx; 3313 Rt_map *lmp1, *lmp = slp->sl_imap; 3314 const char *name = slp->sl_name; 3315 3316 /* 3317 * Generate a local list of new objects to process. This list can grow 3318 * as each object supplies its own lazy dependencies. 3319 */ 3320 if (aplist_append(&alist, lmp, AL_CNT_LAZYFIND) == NULL) 3321 return (NULL); 3322 FLAGS(lmp) |= FLG_RT_TMPLIST; 3323 3324 for (APLIST_TRAVERSE(alist, idx, lmp1)) { 3325 uint_t cnt = 0; 3326 Slookup sl = *slp; 3327 Dyninfo *dip, *pdip; 3328 3329 /* 3330 * Discard any relocation index from further symbol searches. 3331 * This index will have already been used to trigger any 3332 * necessary lazy-loads, and it might be because one of these 3333 * lazy loads have failed that we're here performing this 3334 * fallback. By removing the relocation index we don't try 3335 * and perform the same failed lazy loading activity again. 3336 */ 3337 sl.sl_rsymndx = 0; 3338 3339 /* 3340 * Loop through the lazy DT_NEEDED entries examining each object 3341 * for the required symbol. If the symbol is not found, the 3342 * object is in turn added to the local alist, so that the 3343 * objects lazy DT_NEEDED entries can be examined. 3344 */ 3345 lmp = lmp1; 3346 for (dip = DYNINFO(lmp), pdip = NULL; cnt < DYNINFOCNT(lmp); 3347 cnt++, pdip = dip++) { 3348 Rt_map *nlmp; 3349 3350 if (((dip->di_flags & FLG_DI_LAZY) == 0) || 3351 dip->di_info) 3352 continue; 3353 3354 /* 3355 * If this object has already failed to lazy load, and 3356 * we're still processing the same runtime linker 3357 * operation that produced the failure, don't bother 3358 * to try and load the object again. 3359 */ 3360 if ((dip->di_flags & FLG_DI_LAZYFAIL) && pdip && 3361 (pdip->di_flags & FLG_DI_POSFLAG1)) { 3362 if (pdip->di_info == (void *)ld_entry_cnt) 3363 continue; 3364 3365 dip->di_flags &= ~FLG_DI_LAZYFAIL; 3366 pdip->di_info = NULL; 3367 } 3368 3369 /* 3370 * Try loading this lazy dependency. If the object 3371 * can't be loaded, consider this non-fatal and continue 3372 * the search. Lazy loaded dependencies need not exist 3373 * and their loading should only turn out to be fatal 3374 * if they are required to satisfy a relocation. 3375 * 3376 * If the file is already loaded and relocated we must 3377 * still inspect it for symbols, even though it might 3378 * have already been searched. This lazy load operation 3379 * might have promoted the permissions of the object, 3380 * and thus made the object applicable for this symbol 3381 * search, whereas before the object might have been 3382 * skipped. 3383 */ 3384 if ((nlmp = elf_lazy_load(lmp, &sl, cnt, 3385 name, in_nfavl)) == 0) 3386 continue; 3387 3388 /* 3389 * If this object isn't yet a part of the dynamic list 3390 * then inspect it for the symbol. If the symbol isn't 3391 * found add the object to the dynamic list so that we 3392 * can inspect its dependencies. 3393 */ 3394 if (FLAGS(nlmp) & FLG_RT_TMPLIST) 3395 continue; 3396 3397 sl.sl_imap = nlmp; 3398 if (sym = LM_LOOKUP_SYM(sl.sl_cmap)(&sl, _lmp, 3399 binfo, in_nfavl)) 3400 break; 3401 3402 /* 3403 * Some dlsym() operations are already traversing a 3404 * link-map (dlopen(0)), and thus there's no need to 3405 * build our own dynamic dependency list. 3406 */ 3407 if ((sl.sl_flags & LKUP_NODESCENT) == 0) { 3408 if (aplist_append(&alist, nlmp, 3409 AL_CNT_LAZYFIND) == 0) { 3410 elf_lazy_cleanup(alist); 3411 return (0); 3412 } 3413 FLAGS(nlmp) |= FLG_RT_TMPLIST; 3414 } 3415 } 3416 if (sym) 3417 break; 3418 } 3419 3420 elf_lazy_cleanup(alist); 3421 return (sym); 3422 } 3423 3424 /* 3425 * Warning message for bad r_offset. 3426 */ 3427 void 3428 elf_reloc_bad(Rt_map *lmp, void *rel, uchar_t rtype, ulong_t roffset, 3429 ulong_t rsymndx) 3430 { 3431 const char *name = (char *)0; 3432 Lm_list *lml = LIST(lmp); 3433 int trace; 3434 3435 if ((lml->lm_flags & LML_FLG_TRC_ENABLE) && 3436 (((rtld_flags & RT_FL_SILENCERR) == 0) || 3437 (lml->lm_flags & LML_FLG_TRC_VERBOSE))) 3438 trace = 1; 3439 else 3440 trace = 0; 3441 3442 if ((trace == 0) && (DBG_ENABLED == 0)) 3443 return; 3444 3445 if (rsymndx) { 3446 Sym *symref = (Sym *)((ulong_t)SYMTAB(lmp) + 3447 (rsymndx * SYMENT(lmp))); 3448 3449 if (ELF_ST_BIND(symref->st_info) != STB_LOCAL) 3450 name = (char *)(STRTAB(lmp) + symref->st_name); 3451 } 3452 3453 if (name == 0) 3454 name = MSG_ORIG(MSG_STR_EMPTY); 3455 3456 if (trace) { 3457 const char *rstr; 3458 3459 rstr = _conv_reloc_type((uint_t)rtype); 3460 (void) printf(MSG_INTL(MSG_LDD_REL_ERR1), rstr, name, 3461 EC_ADDR(roffset)); 3462 return; 3463 } 3464 3465 Dbg_reloc_error(lml, ELF_DBG_RTLD, M_MACH, M_REL_SHT_TYPE, rel, name); 3466 } 3467 3468 /* 3469 * Resolve a static TLS relocation. 3470 */ 3471 long 3472 elf_static_tls(Rt_map *lmp, Sym *sym, void *rel, uchar_t rtype, char *name, 3473 ulong_t roffset, long value) 3474 { 3475 Lm_list *lml = LIST(lmp); 3476 3477 /* 3478 * Relocations against a static TLS block have limited support once 3479 * process initialization has completed. Any error condition should be 3480 * discovered by testing for DF_STATIC_TLS as part of loading an object, 3481 * however individual relocations are tested in case the dynamic flag 3482 * had not been set when this object was built. 3483 */ 3484 if (PTTLS(lmp) == 0) { 3485 DBG_CALL(Dbg_reloc_in(lml, ELF_DBG_RTLD, M_MACH, 3486 M_REL_SHT_TYPE, rel, NULL, name)); 3487 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_BADTLS), 3488 _conv_reloc_type((uint_t)rtype), NAME(lmp), 3489 name ? demangle(name) : MSG_INTL(MSG_STR_UNKNOWN)); 3490 return (0); 3491 } 3492 3493 /* 3494 * If no static TLS has been set aside for this object, determine if 3495 * any can be obtained. Enforce that any object using static TLS is 3496 * non-deletable. 3497 */ 3498 if (TLSSTATOFF(lmp) == 0) { 3499 FLAGS1(lmp) |= FL1_RT_TLSSTAT; 3500 MODE(lmp) |= RTLD_NODELETE; 3501 3502 if (tls_assign(lml, lmp, PTTLS(lmp)) == 0) { 3503 DBG_CALL(Dbg_reloc_in(lml, ELF_DBG_RTLD, M_MACH, 3504 M_REL_SHT_TYPE, rel, NULL, name)); 3505 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_BADTLS), 3506 _conv_reloc_type((uint_t)rtype), NAME(lmp), 3507 name ? demangle(name) : MSG_INTL(MSG_STR_UNKNOWN)); 3508 return (0); 3509 } 3510 } 3511 3512 /* 3513 * Typically, a static TLS offset is maintained as a symbols value. 3514 * For local symbols that are not apart of the dynamic symbol table, 3515 * the TLS relocation points to a section symbol, and the static TLS 3516 * offset was deposited in the associated GOT table. Make sure the GOT 3517 * is cleared, so that the value isn't reused in do_reloc(). 3518 */ 3519 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) { 3520 if ((ELF_ST_TYPE(sym->st_info) == STT_SECTION)) { 3521 value = *(long *)roffset; 3522 *(long *)roffset = 0; 3523 } else { 3524 value = sym->st_value; 3525 } 3526 } 3527 return (-(TLSSTATOFF(lmp) - value)); 3528 } 3529 3530 /* 3531 * If the symbol is not found and the reference was not to a weak symbol, report 3532 * an error. Weak references may be unresolved. 3533 */ 3534 int 3535 elf_reloc_error(Rt_map *lmp, const char *name, void *rel, uint_t binfo) 3536 { 3537 Lm_list *lml = LIST(lmp); 3538 3539 /* 3540 * Under crle(1), relocation failures are ignored. 3541 */ 3542 if (lml->lm_flags & LML_FLG_IGNRELERR) 3543 return (1); 3544 3545 /* 3546 * Under ldd(1), unresolved references are reported. However, if the 3547 * original reference is EXTERN or PARENT these references are ignored 3548 * unless ldd's -p option is in effect. 3549 */ 3550 if (lml->lm_flags & LML_FLG_TRC_WARN) { 3551 if (((binfo & DBG_BINFO_REF_MSK) == 0) || 3552 ((lml->lm_flags & LML_FLG_TRC_NOPAREXT) != 0)) { 3553 (void) printf(MSG_INTL(MSG_LDD_SYM_NFOUND), 3554 demangle(name), NAME(lmp)); 3555 } 3556 return (1); 3557 } 3558 3559 /* 3560 * Otherwise, the unresolved references is fatal. 3561 */ 3562 DBG_CALL(Dbg_reloc_in(lml, ELF_DBG_RTLD, M_MACH, M_REL_SHT_TYPE, rel, 3563 NULL, name)); 3564 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_NOSYM), NAME(lmp), 3565 demangle(name)); 3566 3567 return (0); 3568 } 3569