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 (c) 1988 AT&T 24 * All Rights Reserved 25 * 26 * 27 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 28 * Use is subject to license terms. 29 */ 30 31 /* 32 * Symbol table management routines 33 */ 34 35 #define ELF_TARGET_AMD64 36 37 #include <stdio.h> 38 #include <string.h> 39 #include <debug.h> 40 #include "msg.h" 41 #include "_libld.h" 42 43 /* 44 * AVL tree comparator function: 45 * 46 * The primary key is the symbol name hash with a secondary key of the symbol 47 * name itself. 48 */ 49 int 50 ld_sym_avl_comp(const void *elem1, const void *elem2) 51 { 52 Sym_avlnode *sav1 = (Sym_avlnode *)elem1; 53 Sym_avlnode *sav2 = (Sym_avlnode *)elem2; 54 int res; 55 56 res = sav1->sav_hash - sav2->sav_hash; 57 58 if (res < 0) 59 return (-1); 60 if (res > 0) 61 return (1); 62 63 /* 64 * Hash is equal - now compare name 65 */ 66 res = strcmp(sav1->sav_name, sav2->sav_name); 67 if (res == 0) 68 return (0); 69 if (res > 0) 70 return (1); 71 return (-1); 72 } 73 74 /* 75 * Focal point for verifying symbol names. 76 */ 77 inline static const char * 78 string(Ofl_desc *ofl, Ifl_desc *ifl, Sym *sym, const char *strs, size_t strsize, 79 int symndx, Word shndx, const char *symsecname, const char *strsecname, 80 Word *flags) 81 { 82 Word name = sym->st_name; 83 84 if (name) { 85 if ((ifl->ifl_flags & FLG_IF_HSTRTAB) == 0) { 86 eprintf(ofl->ofl_lml, ERR_FATAL, 87 MSG_INTL(MSG_FIL_NOSTRTABLE), ifl->ifl_name, 88 symsecname, symndx, EC_XWORD(name)); 89 return (NULL); 90 } 91 if (name >= (Word)strsize) { 92 eprintf(ofl->ofl_lml, ERR_FATAL, 93 MSG_INTL(MSG_FIL_EXCSTRTABLE), ifl->ifl_name, 94 symsecname, symndx, EC_XWORD(name), 95 strsecname, EC_XWORD(strsize)); 96 return (NULL); 97 } 98 } 99 100 /* 101 * Determine if we're dealing with a register and if so validate it. 102 * If it's a scratch register, a fabricated name will be returned. 103 */ 104 if (ld_targ.t_ms.ms_is_regsym != NULL) { 105 const char *regname = (*ld_targ.t_ms.ms_is_regsym)(ofl, ifl, 106 sym, strs, symndx, shndx, symsecname, flags); 107 108 if (regname == (const char *)S_ERROR) { 109 return (NULL); 110 } 111 if (regname) 112 return (regname); 113 } 114 115 /* 116 * If this isn't a register, but we have a global symbol with a null 117 * name, we're not going to be able to hash this, search for it, or 118 * do anything interesting. However, we've been accepting a symbol of 119 * this kind for ages now, so give the user a warning (rather than a 120 * fatal error), just in case this instance exists somewhere in the 121 * world and hasn't, as yet, been a problem. 122 */ 123 if ((name == 0) && (ELF_ST_BIND(sym->st_info) != STB_LOCAL)) { 124 eprintf(ofl->ofl_lml, ERR_WARNING, MSG_INTL(MSG_FIL_NONAMESYM), 125 ifl->ifl_name, symsecname, symndx, EC_XWORD(name)); 126 } 127 return (strs + name); 128 } 129 130 /* 131 * For producing symbol names strings to use in error messages. 132 * If the symbol has a non-null name, then the string returned by 133 * this function is the output from demangle(), surrounded by 134 * single quotes. For null names, a descriptive string giving 135 * the symbol section and index is generated. 136 * 137 * This function uses an internal static buffer to hold the resulting 138 * string. The value returned is usable by the caller until the next 139 * call, at which point it is overwritten. 140 */ 141 static const char * 142 demangle_symname(const char *name, const char *symtab_name, Word symndx) 143 { 144 #define INIT_BUFSIZE 256 145 146 static char *buf; 147 static size_t bufsize = 0; 148 size_t len; 149 int use_name; 150 151 use_name = (name != NULL) && (*name != '\0'); 152 153 if (use_name) { 154 name = demangle(name); 155 len = strlen(name) + 2; /* Include room for quotes */ 156 } else { 157 name = MSG_ORIG(MSG_STR_EMPTY); 158 len = strlen(symtab_name) + 2 + CONV32_INV_BUFSIZE; 159 } 160 len++; /* Null termination */ 161 162 /* If our buffer is too small, double it until it is big enough */ 163 if (len > bufsize) { 164 size_t new_bufsize = bufsize; 165 char *new_buf; 166 167 if (new_bufsize == 0) 168 new_bufsize = INIT_BUFSIZE; 169 while (len > new_bufsize) 170 new_bufsize *= 2; 171 if ((new_buf = libld_malloc(new_bufsize)) == NULL) 172 return (name); 173 buf = new_buf; 174 bufsize = new_bufsize; 175 } 176 177 if (use_name) { 178 (void) snprintf(buf, bufsize, MSG_ORIG(MSG_FMT_SYMNAM), name); 179 } else { 180 (void) snprintf(buf, bufsize, MSG_ORIG(MSG_FMT_NULLSYMNAM), 181 symtab_name, EC_WORD(symndx)); 182 } 183 184 return (buf); 185 186 #undef INIT_BUFSIZE 187 } 188 189 /* 190 * Shared objects can be built that define specific symbols that can not be 191 * directly bound to. These objects have a syminfo section (and an associated 192 * DF_1_NODIRECT dynamic flags entry). Scan this table looking for symbols 193 * that can't be bound to directly, and if this files symbol is presently 194 * referenced, mark it so that we don't directly bind to it. 195 */ 196 uintptr_t 197 ld_sym_nodirect(Is_desc *isp, Ifl_desc *ifl, Ofl_desc *ofl) 198 { 199 Shdr *sifshdr, *symshdr; 200 Syminfo *sifdata; 201 Sym *symdata; 202 char *strdata; 203 ulong_t cnt, _cnt; 204 205 /* 206 * Get the syminfo data, and determine the number of entries. 207 */ 208 sifshdr = isp->is_shdr; 209 sifdata = (Syminfo *)isp->is_indata->d_buf; 210 cnt = sifshdr->sh_size / sifshdr->sh_entsize; 211 212 /* 213 * Get the associated symbol table. 214 */ 215 symshdr = ifl->ifl_isdesc[sifshdr->sh_link]->is_shdr; 216 symdata = ifl->ifl_isdesc[sifshdr->sh_link]->is_indata->d_buf; 217 218 /* 219 * Get the string table associated with the symbol table. 220 */ 221 strdata = ifl->ifl_isdesc[symshdr->sh_link]->is_indata->d_buf; 222 223 /* 224 * Traverse the syminfo data for symbols that can't be directly 225 * bound to. 226 */ 227 for (_cnt = 1, sifdata++; _cnt < cnt; _cnt++, sifdata++) { 228 Sym *sym; 229 char *str; 230 Sym_desc *sdp; 231 232 if ((sifdata->si_flags & SYMINFO_FLG_NOEXTDIRECT) == 0) 233 continue; 234 235 sym = (Sym *)(symdata + _cnt); 236 str = (char *)(strdata + sym->st_name); 237 238 if (sdp = ld_sym_find(str, SYM_NOHASH, 0, ofl)) { 239 if (ifl != sdp->sd_file) 240 continue; 241 242 sdp->sd_flags1 &= ~FLG_SY1_DIR; 243 sdp->sd_flags1 |= FLG_SY1_NDIR; 244 } 245 } 246 return (0); 247 } 248 249 /* 250 * If, during symbol processing, it is necessary to update a local symbols 251 * contents before we have generated the symbol tables in the output image, 252 * create a new symbol structure and copy the original symbol contents. While 253 * we are processing the input files, their local symbols are part of the 254 * read-only mapped image. Commonly, these symbols are copied to the new output 255 * file image and then updated to reflect their new address and any change in 256 * attributes. However, sometimes during relocation counting, it is necessary 257 * to adjust the symbols information. This routine provides for the generation 258 * of a new symbol image so that this update can be performed. 259 * All global symbols are copied to an internal symbol table to improve locality 260 * of reference and hence performance, and thus this copying is not necessary. 261 */ 262 uintptr_t 263 ld_sym_copy(Sym_desc *sdp) 264 { 265 Sym *nsym; 266 267 if (sdp->sd_flags & FLG_SY_CLEAN) { 268 if ((nsym = libld_malloc(sizeof (Sym))) == NULL) 269 return (S_ERROR); 270 *nsym = *(sdp->sd_sym); 271 sdp->sd_sym = nsym; 272 sdp->sd_flags &= ~FLG_SY_CLEAN; 273 } 274 return (1); 275 } 276 277 /* 278 * Finds a given name in the link editors internal symbol table. If no 279 * hash value is specified it is calculated. A pointer to the located 280 * Sym_desc entry is returned, or NULL if the symbol is not found. 281 */ 282 Sym_desc * 283 ld_sym_find(const char *name, Word hash, avl_index_t *where, Ofl_desc *ofl) 284 { 285 Sym_avlnode qsav, *sav; 286 287 if (hash == SYM_NOHASH) 288 /* LINTED */ 289 hash = (Word)elf_hash((const char *)name); 290 qsav.sav_hash = hash; 291 qsav.sav_name = name; 292 293 /* 294 * Perform search for symbol in AVL tree. Note that the 'where' field 295 * is passed in from the caller. If a 'where' is present, it can be 296 * used in subsequent 'ld_sym_enter()' calls if required. 297 */ 298 sav = avl_find(&ofl->ofl_symavl, &qsav, where); 299 300 /* 301 * If symbol was not found in the avl tree, return null to show that. 302 */ 303 if (sav == NULL) 304 return (NULL); 305 306 /* 307 * Return symbol found. 308 */ 309 return (sav->sav_symdesc); 310 } 311 312 /* 313 * Enter a new symbol into the link editors internal symbol table. 314 * If the symbol is from an input file, information regarding the input file 315 * and input section is also recorded. Otherwise (file == NULL) the symbol 316 * has been internally generated (ie. _etext, _edata, etc.). 317 */ 318 Sym_desc * 319 ld_sym_enter(const char *name, Sym *osym, Word hash, Ifl_desc *ifl, 320 Ofl_desc *ofl, Word ndx, Word shndx, Word sdflags, Half sdflags1, 321 avl_index_t *where) 322 { 323 Sym_desc *sdp; 324 Sym_aux *sap; 325 Sym_avlnode *savl; 326 char *_name; 327 Sym *nsym; 328 Half etype; 329 uchar_t vis; 330 avl_index_t _where; 331 332 /* 333 * Establish the file type. 334 */ 335 if (ifl) 336 etype = ifl->ifl_ehdr->e_type; 337 else 338 etype = ET_NONE; 339 340 ofl->ofl_entercnt++; 341 342 /* 343 * Allocate a Sym Descriptor, Auxiliary Descriptor, and a Sym AVLNode - 344 * contiguously. 345 */ 346 if ((savl = libld_calloc(sizeof (Sym_avlnode) + sizeof (Sym_desc) + 347 sizeof (Sym_aux), 1)) == NULL) 348 return ((Sym_desc *)S_ERROR); 349 sdp = (Sym_desc *)((uintptr_t)savl + sizeof (Sym_avlnode)); 350 sap = (Sym_aux *)((uintptr_t)sdp + sizeof (Sym_desc)); 351 352 savl->sav_symdesc = sdp; 353 sdp->sd_file = ifl; 354 sdp->sd_aux = sap; 355 savl->sav_hash = sap->sa_hash = hash; 356 357 /* 358 * Copy the symbol table entry from the input file into the internal 359 * entry and have the symbol descriptor use it. 360 */ 361 sdp->sd_sym = nsym = &sap->sa_sym; 362 *nsym = *osym; 363 sdp->sd_shndx = shndx; 364 sdp->sd_flags |= sdflags; 365 sdp->sd_flags1 |= sdflags1; 366 367 if ((_name = libld_malloc(strlen(name) + 1)) == NULL) 368 return ((Sym_desc *)S_ERROR); 369 savl->sav_name = sdp->sd_name = (const char *)strcpy(_name, name); 370 371 /* 372 * Enter Symbol in AVL tree. 373 */ 374 if (where == 0) { 375 /* LINTED */ 376 Sym_avlnode *_savl; 377 /* 378 * If a previous ld_sym_find() hasn't initialized 'where' do it 379 * now. 380 */ 381 where = &_where; 382 _savl = avl_find(&ofl->ofl_symavl, savl, where); 383 assert(_savl == NULL); 384 } 385 avl_insert(&ofl->ofl_symavl, savl, *where); 386 387 /* 388 * Record the section index. This is possible because the 389 * `ifl_isdesc' table is filled before we start symbol processing. 390 */ 391 if ((sdflags & FLG_SY_SPECSEC) || (nsym->st_shndx == SHN_UNDEF)) 392 sdp->sd_isc = NULL; 393 else { 394 sdp->sd_isc = ifl->ifl_isdesc[shndx]; 395 396 /* 397 * If this symbol is from a relocatable object, make sure that 398 * it is still associated with a section. For example, an 399 * unknown section type (SHT_NULL) would have been rejected on 400 * input with a warning. Here, we make the use of the symbol 401 * fatal. A symbol descriptor is still returned, so that the 402 * caller can continue processing all symbols, and hence flush 403 * out as many error conditions as possible. 404 */ 405 if ((etype == ET_REL) && (sdp->sd_isc == NULL)) { 406 eprintf(ofl->ofl_lml, ERR_FATAL, 407 MSG_INTL(MSG_SYM_INVSEC), name, ifl->ifl_name, 408 EC_XWORD(shndx)); 409 ofl->ofl_flags |= FLG_OF_FATAL; 410 return (sdp); 411 } 412 } 413 414 /* 415 * Mark any COMMON symbols as 'tentative'. 416 */ 417 if (sdflags & FLG_SY_SPECSEC) { 418 if (nsym->st_shndx == SHN_COMMON) 419 sdp->sd_flags |= FLG_SY_TENTSYM; 420 #if defined(_ELF64) 421 else if ((ld_targ.t_m.m_mach == EM_AMD64) && 422 (nsym->st_shndx == SHN_X86_64_LCOMMON)) 423 sdp->sd_flags |= FLG_SY_TENTSYM; 424 #endif 425 } 426 427 /* 428 * Establish the symbols visibility and reference. 429 */ 430 vis = ELF_ST_VISIBILITY(nsym->st_other); 431 432 if ((etype == ET_NONE) || (etype == ET_REL)) { 433 switch (vis) { 434 case STV_DEFAULT: 435 sdp->sd_flags1 |= FLG_SY1_DEFAULT; 436 break; 437 case STV_INTERNAL: 438 case STV_HIDDEN: 439 sdp->sd_flags1 |= FLG_SY1_HIDDEN; 440 break; 441 case STV_PROTECTED: 442 sdp->sd_flags1 |= FLG_SY1_PROTECT; 443 break; 444 case STV_EXPORTED: 445 sdp->sd_flags1 |= FLG_SY1_EXPORT; 446 break; 447 case STV_SINGLETON: 448 sdp->sd_flags1 |= (FLG_SY1_SINGLE | FLG_SY1_NDIR); 449 ofl->ofl_flags1 |= FLG_OF1_NDIRECT; 450 break; 451 case STV_ELIMINATE: 452 sdp->sd_flags1 |= (FLG_SY1_HIDDEN | FLG_SY1_ELIM); 453 break; 454 default: 455 assert(vis <= STV_ELIMINATE); 456 } 457 458 sdp->sd_ref = REF_REL_NEED; 459 460 /* 461 * Under -Bnodirect, all exported interfaces that have not 462 * explicitly been defined protected or directly bound to, are 463 * tagged to prevent direct binding. 464 */ 465 if ((ofl->ofl_flags1 & FLG_OF1_ALNODIR) && 466 ((sdp->sd_flags1 & (FLG_SY1_PROTECT | FLG_SY1_DIR)) == 0) && 467 (nsym->st_shndx != SHN_UNDEF)) { 468 sdp->sd_flags1 |= FLG_SY1_NDIR; 469 } 470 } else { 471 sdp->sd_ref = REF_DYN_SEEN; 472 473 /* 474 * Record the binding file for this symbol in the sa_bindto 475 * field. If this symbol is ever overridden by a REF_REL_NEED 476 * definition, sa_bindto is used when building a 'translator'. 477 */ 478 if (nsym->st_shndx != SHN_UNDEF) 479 sdp->sd_aux->sa_bindto = ifl; 480 481 /* 482 * If this is a protected symbol, remember this. Note, this 483 * state is different from the FLG_SY1_PROTECT used to establish 484 * a symbol definitions visibility. This state is used to warn 485 * against possible copy relocations against this referenced 486 * symbol. 487 */ 488 if (vis == STV_PROTECTED) 489 sdp->sd_flags |= FLG_SY_PROT; 490 491 /* 492 * If this is a SINGLETON definition, then indicate the symbol 493 * can not be directly bound to, and retain the visibility. 494 * This visibility will be inherited by any references made to 495 * this symbol. 496 */ 497 if ((vis == STV_SINGLETON) && (nsym->st_shndx != SHN_UNDEF)) 498 sdp->sd_flags1 |= (FLG_SY1_SINGLE | FLG_SY1_NDIR); 499 500 /* 501 * If the new symbol is from a shared library and is associated 502 * with a SHT_NOBITS section then this symbol originated from a 503 * tentative symbol. 504 */ 505 if (sdp->sd_isc && 506 (sdp->sd_isc->is_shdr->sh_type == SHT_NOBITS)) 507 sdp->sd_flags |= FLG_SY_TENTSYM; 508 } 509 510 /* 511 * Reclassify any SHN_SUNW_IGNORE symbols to SHN_UNDEF so as to 512 * simplify future processing. 513 */ 514 if (nsym->st_shndx == SHN_SUNW_IGNORE) { 515 sdp->sd_shndx = shndx = SHN_UNDEF; 516 sdp->sd_flags |= FLG_SY_REDUCED; 517 sdp->sd_flags1 |= 518 (FLG_SY1_HIDDEN | FLG_SY1_IGNORE | FLG_SY1_ELIM); 519 } 520 521 /* 522 * If this is an undefined, or common symbol from a relocatable object 523 * determine whether it is a global or weak reference (see build_osym(), 524 * where REF_DYN_NEED definitions are returned back to undefines). 525 */ 526 if ((etype == ET_REL) && 527 (ELF_ST_BIND(nsym->st_info) == STB_GLOBAL) && 528 ((nsym->st_shndx == SHN_UNDEF) || ((sdflags & FLG_SY_SPECSEC) && 529 #if defined(_ELF64) 530 ((nsym->st_shndx == SHN_COMMON) || 531 ((ld_targ.t_m.m_mach == EM_AMD64) && 532 (nsym->st_shndx == SHN_X86_64_LCOMMON)))))) 533 #else 534 /* BEGIN CSTYLED */ 535 (nsym->st_shndx == SHN_COMMON)))) 536 /* END CSTYLED */ 537 #endif 538 sdp->sd_flags |= FLG_SY_GLOBREF; 539 540 /* 541 * Record the input filename on the referenced or defined files list 542 * for possible later diagnostics. The `sa_rfile' pointer contains the 543 * name of the file that first referenced this symbol and is used to 544 * generate undefined symbol diagnostics (refer to sym_undef_entry()). 545 * Note that this entry can be overridden if a reference from a 546 * relocatable object is found after a reference from a shared object 547 * (refer to sym_override()). 548 * The `sa_dfiles' list is used to maintain the list of files that 549 * define the same symbol. This list can be used for two reasons: 550 * 551 * - To save the first definition of a symbol that is not available 552 * for this link-edit. 553 * 554 * - To save all definitions of a symbol when the -m option is in 555 * effect. This is optional as it is used to list multiple 556 * (interposed) definitions of a symbol (refer to ldmap_out()), 557 * and can be quite expensive. 558 */ 559 if (nsym->st_shndx == SHN_UNDEF) { 560 sap->sa_rfile = ifl->ifl_name; 561 } else { 562 if (sdp->sd_ref == REF_DYN_SEEN) { 563 /* 564 * A symbol is determined to be unavailable if it 565 * belongs to a version of a shared object that this 566 * user does not wish to use, or if it belongs to an 567 * implicit shared object. 568 */ 569 if (ifl->ifl_vercnt) { 570 Ver_index *vip; 571 Half vndx = ifl->ifl_versym[ndx]; 572 573 sap->sa_dverndx = vndx; 574 vip = &ifl->ifl_verndx[vndx]; 575 if (!(vip->vi_flags & FLG_VER_AVAIL)) { 576 sdp->sd_flags |= FLG_SY_NOTAVAIL; 577 sap->sa_vfile = ifl->ifl_name; 578 } 579 } 580 if (!(ifl->ifl_flags & FLG_IF_NEEDED)) 581 sdp->sd_flags |= FLG_SY_NOTAVAIL; 582 583 } else if (etype == ET_REL) { 584 /* 585 * If this symbol has been obtained from a versioned 586 * input relocatable object then the new symbol must be 587 * promoted to the versioning of the output file. 588 */ 589 if (ifl->ifl_versym) 590 ld_vers_promote(sdp, ndx, ifl, ofl); 591 } 592 593 if ((ofl->ofl_flags & FLG_OF_GENMAP) && 594 ((sdflags & FLG_SY_SPECSEC) == 0)) 595 if (aplist_append(&sap->sa_dfiles, ifl->ifl_name, 596 AL_CNT_SDP_DFILES) == NULL) 597 return ((Sym_desc *)S_ERROR); 598 } 599 600 /* 601 * Provided we're not processing a mapfile, diagnose the entered symbol. 602 * Mapfile processing requires the symbol to be updated with additional 603 * information, therefore the diagnosing of the symbol is deferred until 604 * later (see Dbg_map_symbol()). 605 */ 606 if ((ifl == NULL) || ((ifl->ifl_flags & FLG_IF_MAPFILE) == 0)) 607 DBG_CALL(Dbg_syms_entered(ofl, nsym, sdp)); 608 return (sdp); 609 } 610 611 /* 612 * Add a special symbol to the symbol table. Takes special symbol name with 613 * and without underscores. This routine is called, after all other symbol 614 * resolution has completed, to generate a reserved absolute symbol (the 615 * underscore version). Special symbols are updated with the appropriate 616 * values in update_osym(). If the user has already defined this symbol 617 * issue a warning and leave the symbol as is. If the non-underscore symbol 618 * is referenced then turn it into a weak alias of the underscored symbol. 619 * 620 * The bits in flags_u are OR'd into the flags field of the symbol 621 * for the underscored symbol. 622 * 623 * If this is a global symbol, and it hasn't explicitly been defined as being 624 * directly bound to, indicate that it can't be directly bound to. 625 * Historically, most special symbols only have meaning to the object in which 626 * they exist, however, they've always been global. To ensure compatibility 627 * with any unexpected use presently in effect, ensure these symbols don't get 628 * directly bound to. Note, that establishing this state here isn't sufficient 629 * to create a syminfo table, only if a syminfo table is being created by some 630 * other symbol directives will the nodirect binding be recorded. This ensures 631 * we don't create syminfo sections for all objects we create, as this might add 632 * unnecessary bloat to users who haven't explicitly requested extra symbol 633 * information. 634 */ 635 static uintptr_t 636 sym_add_spec(const char *name, const char *uname, Word sdaux_id, 637 Word flags_u, Half flags1, Ofl_desc *ofl) 638 { 639 Sym_desc *sdp; 640 Sym_desc *usdp; 641 Sym *sym; 642 Word hash; 643 avl_index_t where; 644 645 /* LINTED */ 646 hash = (Word)elf_hash(uname); 647 if (usdp = ld_sym_find(uname, hash, &where, ofl)) { 648 /* 649 * If the underscore symbol exists and is undefined, or was 650 * defined in a shared library, convert it to a local symbol. 651 * Otherwise leave it as is and warn the user. 652 */ 653 if ((usdp->sd_shndx == SHN_UNDEF) || 654 (usdp->sd_ref != REF_REL_NEED)) { 655 usdp->sd_ref = REF_REL_NEED; 656 usdp->sd_shndx = usdp->sd_sym->st_shndx = SHN_ABS; 657 usdp->sd_flags |= FLG_SY_SPECSEC | flags_u; 658 usdp->sd_sym->st_info = 659 ELF_ST_INFO(STB_GLOBAL, STT_OBJECT); 660 usdp->sd_isc = NULL; 661 usdp->sd_sym->st_size = 0; 662 usdp->sd_sym->st_value = 0; 663 /* LINTED */ 664 usdp->sd_aux->sa_symspec = (Half)sdaux_id; 665 666 /* 667 * If a user hasn't specifically indicated that the 668 * scope of this symbol be made local, then leave it 669 * as global (ie. prevent automatic scoping). The GOT 670 * should be defined protected, whereas all other 671 * special symbols are tagged as no-direct. 672 */ 673 if (((usdp->sd_flags1 & FLG_SY1_HIDDEN) == 0) && 674 (flags1 & FLG_SY1_DEFAULT)) { 675 usdp->sd_aux->sa_overndx = VER_NDX_GLOBAL; 676 if (sdaux_id == SDAUX_ID_GOT) { 677 usdp->sd_flags1 &= ~FLG_SY1_NDIR; 678 usdp->sd_flags1 |= FLG_SY1_PROTECT; 679 usdp->sd_sym->st_other = STV_PROTECTED; 680 } else if ( 681 ((usdp->sd_flags1 & FLG_SY1_DIR) == 0) && 682 ((ofl->ofl_flags & FLG_OF_SYMBOLIC) == 0)) { 683 usdp->sd_flags1 |= FLG_SY1_NDIR; 684 } 685 } 686 usdp->sd_flags1 |= flags1; 687 688 /* 689 * If the reference originated from a mapfile ensure 690 * we mark the symbol as used. 691 */ 692 if (usdp->sd_flags & FLG_SY_MAPREF) 693 usdp->sd_flags |= FLG_SY_MAPUSED; 694 695 DBG_CALL(Dbg_syms_updated(ofl, usdp, uname)); 696 } else 697 eprintf(ofl->ofl_lml, ERR_WARNING, 698 MSG_INTL(MSG_SYM_RESERVE), uname, 699 usdp->sd_file->ifl_name); 700 } else { 701 /* 702 * If the symbol does not exist create it. 703 */ 704 if ((sym = libld_calloc(sizeof (Sym), 1)) == NULL) 705 return (S_ERROR); 706 sym->st_shndx = SHN_ABS; 707 sym->st_info = ELF_ST_INFO(STB_GLOBAL, STT_OBJECT); 708 sym->st_size = 0; 709 sym->st_value = 0; 710 DBG_CALL(Dbg_syms_created(ofl->ofl_lml, uname)); 711 if ((usdp = ld_sym_enter(uname, sym, hash, (Ifl_desc *)NULL, 712 ofl, 0, SHN_ABS, FLG_SY_SPECSEC | flags_u, 0, &where)) == 713 (Sym_desc *)S_ERROR) 714 return (S_ERROR); 715 usdp->sd_ref = REF_REL_NEED; 716 /* LINTED */ 717 usdp->sd_aux->sa_symspec = (Half)sdaux_id; 718 719 usdp->sd_aux->sa_overndx = VER_NDX_GLOBAL; 720 721 if (sdaux_id == SDAUX_ID_GOT) { 722 usdp->sd_flags1 |= FLG_SY1_PROTECT; 723 usdp->sd_sym->st_other = STV_PROTECTED; 724 } else if ((flags1 & FLG_SY1_DEFAULT) && 725 ((ofl->ofl_flags & FLG_OF_SYMBOLIC) == 0)) { 726 usdp->sd_flags1 |= FLG_SY1_NDIR; 727 } 728 usdp->sd_flags1 |= flags1; 729 } 730 731 if (name && (sdp = ld_sym_find(name, SYM_NOHASH, 0, ofl)) && 732 (sdp->sd_sym->st_shndx == SHN_UNDEF)) { 733 uchar_t bind; 734 735 /* 736 * If the non-underscore symbol exists and is undefined 737 * convert it to be a local. If the underscore has 738 * sa_symspec set (ie. it was created above) then simulate this 739 * as a weak alias. 740 */ 741 sdp->sd_ref = REF_REL_NEED; 742 sdp->sd_shndx = sdp->sd_sym->st_shndx = SHN_ABS; 743 sdp->sd_flags |= FLG_SY_SPECSEC; 744 sdp->sd_isc = NULL; 745 sdp->sd_sym->st_size = 0; 746 sdp->sd_sym->st_value = 0; 747 /* LINTED */ 748 sdp->sd_aux->sa_symspec = (Half)sdaux_id; 749 if (usdp->sd_aux->sa_symspec) { 750 usdp->sd_aux->sa_linkndx = 0; 751 sdp->sd_aux->sa_linkndx = 0; 752 bind = STB_WEAK; 753 } else 754 bind = STB_GLOBAL; 755 sdp->sd_sym->st_info = ELF_ST_INFO(bind, STT_OBJECT); 756 757 /* 758 * If a user hasn't specifically indicated the scope of this 759 * symbol be made local then leave it as global (ie. prevent 760 * automatic scoping). The GOT should be defined protected, 761 * whereas all other special symbols are tagged as no-direct. 762 */ 763 if (((sdp->sd_flags1 & FLG_SY1_HIDDEN) == 0) && 764 (flags1 & FLG_SY1_DEFAULT)) { 765 sdp->sd_aux->sa_overndx = VER_NDX_GLOBAL; 766 if (sdaux_id == SDAUX_ID_GOT) { 767 sdp->sd_flags1 &= ~FLG_SY1_NDIR; 768 sdp->sd_flags1 |= FLG_SY1_PROTECT; 769 sdp->sd_sym->st_other = STV_PROTECTED; 770 } else if (((sdp->sd_flags1 & FLG_SY1_DIR) == 0) && 771 ((ofl->ofl_flags & FLG_OF_SYMBOLIC) == 0)) { 772 sdp->sd_flags1 |= FLG_SY1_NDIR; 773 } 774 } 775 sdp->sd_flags1 |= flags1; 776 777 /* 778 * If the reference originated from a mapfile ensure 779 * we mark the symbol as used. 780 */ 781 if (sdp->sd_flags & FLG_SY_MAPREF) 782 sdp->sd_flags |= FLG_SY_MAPUSED; 783 784 DBG_CALL(Dbg_syms_updated(ofl, sdp, name)); 785 } 786 return (1); 787 } 788 789 790 /* 791 * Print undefined symbols. 792 */ 793 static Boolean undef_title = TRUE; 794 795 static void 796 sym_undef_title(Ofl_desc *ofl) 797 { 798 eprintf(ofl->ofl_lml, ERR_NONE, MSG_INTL(MSG_SYM_FMT_UNDEF), 799 MSG_INTL(MSG_SYM_UNDEF_ITM_11), 800 MSG_INTL(MSG_SYM_UNDEF_ITM_21), 801 MSG_INTL(MSG_SYM_UNDEF_ITM_12), 802 MSG_INTL(MSG_SYM_UNDEF_ITM_22)); 803 804 undef_title = FALSE; 805 } 806 807 /* 808 * Undefined symbols can fall into one of four types: 809 * 810 * - the symbol is really undefined (SHN_UNDEF). 811 * 812 * - versioning has been enabled, however this symbol has not been assigned 813 * to one of the defined versions. 814 * 815 * - the symbol has been defined by an implicitly supplied library, ie. one 816 * which was encounted because it was NEEDED by another library, rather 817 * than from a command line supplied library which would become the only 818 * dependency of the output file being produced. 819 * 820 * - the symbol has been defined by a version of a shared object that is 821 * not permitted for this link-edit. 822 * 823 * In all cases the file who made the first reference to this symbol will have 824 * been recorded via the `sa_rfile' pointer. 825 */ 826 typedef enum { 827 UNDEF, NOVERSION, IMPLICIT, NOTAVAIL, 828 BNDLOCAL 829 } Type; 830 831 static const Msg format[] = { 832 MSG_SYM_UND_UNDEF, /* MSG_INTL(MSG_SYM_UND_UNDEF) */ 833 MSG_SYM_UND_NOVER, /* MSG_INTL(MSG_SYM_UND_NOVER) */ 834 MSG_SYM_UND_IMPL, /* MSG_INTL(MSG_SYM_UND_IMPL) */ 835 MSG_SYM_UND_NOTA, /* MSG_INTL(MSG_SYM_UND_NOTA) */ 836 MSG_SYM_UND_BNDLOCAL /* MSG_INTL(MSG_SYM_UND_BNDLOCAL) */ 837 }; 838 839 static void 840 sym_undef_entry(Ofl_desc *ofl, Sym_desc *sdp, Type type) 841 { 842 const char *name1, *name2, *name3; 843 Ifl_desc *ifl = sdp->sd_file; 844 Sym_aux *sap = sdp->sd_aux; 845 846 if (undef_title) 847 sym_undef_title(ofl); 848 849 switch (type) { 850 case UNDEF: 851 case BNDLOCAL: 852 name1 = sap->sa_rfile; 853 break; 854 case NOVERSION: 855 name1 = ifl->ifl_name; 856 break; 857 case IMPLICIT: 858 name1 = sap->sa_rfile; 859 name2 = ifl->ifl_name; 860 break; 861 case NOTAVAIL: 862 name1 = sap->sa_rfile; 863 name2 = sap->sa_vfile; 864 name3 = ifl->ifl_verndx[sap->sa_dverndx].vi_name; 865 break; 866 default: 867 return; 868 } 869 870 eprintf(ofl->ofl_lml, ERR_NONE, MSG_INTL(format[type]), 871 demangle(sdp->sd_name), name1, name2, name3); 872 } 873 874 /* 875 * At this point all symbol input processing has been completed, therefore 876 * complete the symbol table entries by generating any necessary internal 877 * symbols. 878 */ 879 uintptr_t 880 ld_sym_spec(Ofl_desc *ofl) 881 { 882 Sym_desc *sdp; 883 884 if (ofl->ofl_flags & FLG_OF_RELOBJ) 885 return (1); 886 887 DBG_CALL(Dbg_syms_spec_title(ofl->ofl_lml)); 888 889 if (sym_add_spec(MSG_ORIG(MSG_SYM_ETEXT), MSG_ORIG(MSG_SYM_ETEXT_U), 890 SDAUX_ID_ETEXT, 0, (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), 891 ofl) == S_ERROR) 892 return (S_ERROR); 893 if (sym_add_spec(MSG_ORIG(MSG_SYM_EDATA), MSG_ORIG(MSG_SYM_EDATA_U), 894 SDAUX_ID_EDATA, 0, (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), 895 ofl) == S_ERROR) 896 return (S_ERROR); 897 if (sym_add_spec(MSG_ORIG(MSG_SYM_END), MSG_ORIG(MSG_SYM_END_U), 898 SDAUX_ID_END, FLG_SY_DYNSORT, (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), 899 ofl) == S_ERROR) 900 return (S_ERROR); 901 if (sym_add_spec(MSG_ORIG(MSG_SYM_L_END), MSG_ORIG(MSG_SYM_L_END_U), 902 SDAUX_ID_END, 0, FLG_SY1_HIDDEN, ofl) == S_ERROR) 903 return (S_ERROR); 904 if (sym_add_spec(MSG_ORIG(MSG_SYM_L_START), MSG_ORIG(MSG_SYM_L_START_U), 905 SDAUX_ID_START, 0, FLG_SY1_HIDDEN, ofl) == S_ERROR) 906 return (S_ERROR); 907 908 /* 909 * Historically we've always produced a _DYNAMIC symbol, even for 910 * static executables (in which case its value will be 0). 911 */ 912 if (sym_add_spec(MSG_ORIG(MSG_SYM_DYNAMIC), MSG_ORIG(MSG_SYM_DYNAMIC_U), 913 SDAUX_ID_DYN, FLG_SY_DYNSORT, (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), 914 ofl) == S_ERROR) 915 return (S_ERROR); 916 917 if (OFL_ALLOW_DYNSYM(ofl)) 918 if (sym_add_spec(MSG_ORIG(MSG_SYM_PLKTBL), 919 MSG_ORIG(MSG_SYM_PLKTBL_U), SDAUX_ID_PLT, 920 FLG_SY_DYNSORT, (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), 921 ofl) == S_ERROR) 922 return (S_ERROR); 923 924 /* 925 * A GOT reference will be accompanied by the associated GOT symbol. 926 * Make sure it gets assigned the appropriate special attributes. 927 */ 928 if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_GOFTBL_U), 929 SYM_NOHASH, 0, ofl)) != 0) && (sdp->sd_ref != REF_DYN_SEEN)) { 930 if (sym_add_spec(MSG_ORIG(MSG_SYM_GOFTBL), 931 MSG_ORIG(MSG_SYM_GOFTBL_U), SDAUX_ID_GOT, FLG_SY_DYNSORT, 932 (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), ofl) == S_ERROR) 933 return (S_ERROR); 934 } 935 936 return (1); 937 } 938 939 /* 940 * This routine checks to see if a symbols visibility needs to be reduced to 941 * either SYMBOLIC or LOCAL. This routine can be called from either 942 * reloc_init() or sym_validate(). 943 */ 944 void 945 ld_sym_adjust_vis(Sym_desc *sdp, Ofl_desc *ofl) 946 { 947 ofl_flag_t oflags = ofl->ofl_flags; 948 Sym *sym = sdp->sd_sym; 949 950 if ((sdp->sd_ref == REF_REL_NEED) && 951 (sdp->sd_sym->st_shndx != SHN_UNDEF)) { 952 /* 953 * If auto-reduction/elimination is enabled, reduce any 954 * non-versioned global symbols. This routine is called either 955 * from any initial relocation processing that references this 956 * symbol, or from the symbol validation processing. 957 * 958 * A symbol is a candidate for auto-reduction/elimination if: 959 * 960 * . the symbol wasn't explicitly defined within a mapfile 961 * (in which case all the necessary state has been applied 962 * to the symbol), or 963 * . the symbol isn't one of the family of reserved 964 * special symbols (ie. _end, _etext, etc.), or 965 * . the symbol isn't a SINGLETON, or 966 * . the symbol wasn't explicitly defined within a version 967 * definition associated with an input relocatable object. 968 * 969 * Indicate that the symbol has been reduced as it may be 970 * necessary to print these symbols later. 971 */ 972 if ((oflags & (FLG_OF_AUTOLCL | FLG_OF_AUTOELM)) && 973 ((sdp->sd_flags1 & MSK_SY1_NOAUTO) == 0)) { 974 if ((sdp->sd_flags1 & FLG_SY1_HIDDEN) == 0) { 975 sdp->sd_flags |= FLG_SY_REDUCED; 976 sdp->sd_flags1 |= FLG_SY1_HIDDEN; 977 } 978 979 if (oflags & (FLG_OF_REDLSYM | FLG_OF_AUTOELM)) { 980 sdp->sd_flags1 |= FLG_SY1_ELIM; 981 sym->st_other = STV_ELIMINATE | 982 (sym->st_other & ~MSK_SYM_VISIBILITY); 983 } else if (ELF_ST_VISIBILITY(sym->st_other) != 984 STV_INTERNAL) 985 sym->st_other = STV_HIDDEN | 986 (sym->st_other & ~MSK_SYM_VISIBILITY); 987 } 988 989 /* 990 * If -Bsymbolic is in effect, and the symbol hasn't explicitly 991 * been defined nodirect (via a mapfile), then bind the global 992 * symbol symbolically and assign the STV_PROTECTED visibility 993 * attribute. 994 */ 995 if ((oflags & FLG_OF_SYMBOLIC) && 996 ((sdp->sd_flags1 & (FLG_SY1_HIDDEN | FLG_SY1_NDIR)) == 0)) { 997 sdp->sd_flags1 |= FLG_SY1_PROTECT; 998 if (ELF_ST_VISIBILITY(sym->st_other) == STV_DEFAULT) 999 sym->st_other = STV_PROTECTED | 1000 (sym->st_other & ~MSK_SYM_VISIBILITY); 1001 } 1002 } 1003 1004 /* 1005 * Indicate that this symbol has had it's visibility checked so that 1006 * we don't need to do this investigation again. 1007 */ 1008 sdp->sd_flags |= FLG_SY_VISIBLE; 1009 } 1010 1011 /* 1012 * Make sure a symbol definition is local to the object being built. 1013 */ 1014 inline static int 1015 ensure_sym_local(Ofl_desc *ofl, Sym_desc *sdp, const char *str) 1016 { 1017 if (sdp->sd_sym->st_shndx == SHN_UNDEF) { 1018 if (str) { 1019 eprintf(ofl->ofl_lml, ERR_FATAL, 1020 MSG_INTL(MSG_SYM_UNDEF), str, 1021 demangle((char *)sdp->sd_name)); 1022 } 1023 return (1); 1024 } 1025 if (sdp->sd_ref != REF_REL_NEED) { 1026 if (str) { 1027 eprintf(ofl->ofl_lml, ERR_FATAL, 1028 MSG_INTL(MSG_SYM_EXTERN), str, 1029 demangle((char *)sdp->sd_name), 1030 sdp->sd_file->ifl_name); 1031 } 1032 return (1); 1033 } 1034 1035 sdp->sd_flags |= FLG_SY_UPREQD; 1036 if (sdp->sd_isc) { 1037 sdp->sd_isc->is_flags |= FLG_IS_SECTREF; 1038 sdp->sd_isc->is_file->ifl_flags |= FLG_IF_FILEREF; 1039 } 1040 return (0); 1041 } 1042 1043 /* 1044 * Make sure all the symbol definitions required for initarray, finiarray, or 1045 * preinitarray's are local to the object being built. 1046 */ 1047 static int 1048 ensure_array_local(Ofl_desc *ofl, APlist *apl, const char *str) 1049 { 1050 Aliste idx; 1051 Sym_desc *sdp; 1052 int ret = 0; 1053 1054 for (APLIST_TRAVERSE(apl, idx, sdp)) 1055 ret += ensure_sym_local(ofl, sdp, str); 1056 1057 return (ret); 1058 } 1059 1060 /* 1061 * After all symbol table input processing has been finished, and all relocation 1062 * counting has been carried out (ie. no more symbols will be read, generated, 1063 * or modified), validate and count the relevant entries: 1064 * 1065 * - check and print any undefined symbols remaining. Note that 1066 * if a symbol has been defined by virtue of the inclusion of 1067 * an implicit shared library, it is still classed as undefined. 1068 * 1069 * - count the number of global needed symbols together with the 1070 * size of their associated name strings (if scoping has been 1071 * indicated these symbols may be reduced to locals). 1072 * 1073 * - establish the size and alignment requirements for the global 1074 * .bss section (the alignment of this section is based on the 1075 * first symbol that it will contain). 1076 */ 1077 uintptr_t 1078 ld_sym_validate(Ofl_desc *ofl) 1079 { 1080 Sym_avlnode *sav; 1081 Sym_desc *sdp; 1082 Sym *sym; 1083 ofl_flag_t oflags = ofl->ofl_flags; 1084 ofl_flag_t undef = 0, needed = 0, verdesc = 0; 1085 Xword bssalign = 0, tlsalign = 0; 1086 Xword bsssize = 0, tlssize = 0; 1087 #if defined(_ELF64) 1088 Xword lbssalign = 0, lbsssize = 0; 1089 #endif 1090 int ret; 1091 int allow_ldynsym; 1092 uchar_t type; 1093 1094 /* 1095 * If a symbol is undefined and this link-edit calls for no undefined 1096 * symbols to remain (this is the default case when generating an 1097 * executable but can be enforced for any object using -z defs), the 1098 * symbol is classified as undefined and a fatal error condition will 1099 * be indicated. 1100 * 1101 * If the symbol is undefined and we're creating a shared object with 1102 * the -Bsymbolic flag, then the symbol is also classified as undefined 1103 * and a warning condition will be indicated. 1104 */ 1105 if ((oflags & (FLG_OF_SHAROBJ | FLG_OF_SYMBOLIC)) == 1106 (FLG_OF_SHAROBJ | FLG_OF_SYMBOLIC)) 1107 undef = FLG_OF_WARN; 1108 if (oflags & FLG_OF_NOUNDEF) 1109 undef = FLG_OF_FATAL; 1110 1111 /* 1112 * If the symbol is referenced from an implicitly included shared object 1113 * (ie. it's not on the NEEDED list) then the symbol is also classified 1114 * as undefined and a fatal error condition will be indicated. 1115 */ 1116 if ((oflags & FLG_OF_NOUNDEF) || !(oflags & FLG_OF_SHAROBJ)) 1117 needed = FLG_OF_FATAL; 1118 1119 /* 1120 * If the output image is being versioned all symbol definitions must be 1121 * associated with a version. Any symbol that isn't is classified as 1122 * undefined and a fatal error condition will be indicated. 1123 */ 1124 if ((oflags & FLG_OF_VERDEF) && (ofl->ofl_vercnt > VER_NDX_GLOBAL)) 1125 verdesc = FLG_OF_FATAL; 1126 1127 allow_ldynsym = OFL_ALLOW_LDYNSYM(ofl); 1128 1129 if (allow_ldynsym) { 1130 /* 1131 * Normally, we disallow symbols with 0 size from appearing 1132 * in a dyn[sym|tls]sort section. However, there are some 1133 * symbols that serve special purposes that we want to exempt 1134 * from this rule. Look them up, and set their 1135 * FLG_SY_DYNSORT flag. 1136 */ 1137 static const char *special[] = { 1138 MSG_ORIG(MSG_SYM_INIT_U), /* _init */ 1139 MSG_ORIG(MSG_SYM_FINI_U), /* _fini */ 1140 MSG_ORIG(MSG_SYM_START), /* _start */ 1141 NULL 1142 }; 1143 int i; 1144 1145 for (i = 0; special[i] != NULL; i++) { 1146 if (((sdp = ld_sym_find(special[i], 1147 SYM_NOHASH, 0, ofl)) != NULL) && 1148 (sdp->sd_sym->st_size == 0)) { 1149 if (ld_sym_copy(sdp) == S_ERROR) 1150 return (S_ERROR); 1151 sdp->sd_flags |= FLG_SY_DYNSORT; 1152 } 1153 } 1154 } 1155 1156 /* 1157 * Collect and validate the globals from the internal symbol table. 1158 */ 1159 for (sav = avl_first(&ofl->ofl_symavl); sav; 1160 sav = AVL_NEXT(&ofl->ofl_symavl, sav)) { 1161 Is_desc *isp; 1162 int undeferr = 0; 1163 uchar_t vis; 1164 1165 sdp = sav->sav_symdesc; 1166 1167 /* 1168 * If undefined symbols are allowed ignore any symbols that are 1169 * not needed. 1170 */ 1171 if (!(oflags & FLG_OF_NOUNDEF) && 1172 (sdp->sd_ref == REF_DYN_SEEN)) 1173 continue; 1174 1175 /* 1176 * If the symbol originates from an external or parent mapfile 1177 * reference and hasn't been matched to a reference from a 1178 * relocatable object, ignore it. 1179 */ 1180 if ((sdp->sd_flags & (FLG_SY_EXTERN | FLG_SY_PARENT)) && 1181 ((sdp->sd_flags & FLG_SY_MAPUSED) == 0)) { 1182 sdp->sd_flags |= FLG_SY_INVALID; 1183 continue; 1184 } 1185 1186 sym = sdp->sd_sym; 1187 type = ELF_ST_TYPE(sym->st_info); 1188 1189 /* 1190 * Sanity check TLS. 1191 */ 1192 if ((type == STT_TLS) && (sym->st_size != 0) && 1193 (sym->st_shndx != SHN_UNDEF) && 1194 (sym->st_shndx != SHN_COMMON)) { 1195 Is_desc *isp = sdp->sd_isc; 1196 Ifl_desc *ifl = sdp->sd_file; 1197 1198 if ((isp == NULL) || (isp->is_shdr == NULL) || 1199 ((isp->is_shdr->sh_flags & SHF_TLS) == 0)) { 1200 eprintf(ofl->ofl_lml, ERR_FATAL, 1201 MSG_INTL(MSG_SYM_TLS), 1202 demangle(sdp->sd_name), ifl->ifl_name); 1203 ofl->ofl_flags |= FLG_OF_FATAL; 1204 continue; 1205 } 1206 } 1207 1208 if ((sdp->sd_flags & FLG_SY_VISIBLE) == 0) 1209 ld_sym_adjust_vis(sdp, ofl); 1210 1211 if ((sdp->sd_flags & FLG_SY_REDUCED) && 1212 (oflags & FLG_OF_PROCRED)) { 1213 DBG_CALL(Dbg_syms_reduce(ofl, DBG_SYM_REDUCE_GLOBAL, 1214 sdp, 0, 0)); 1215 } 1216 1217 /* 1218 * Record any STV_SINGLETON existence. 1219 */ 1220 if ((vis = ELF_ST_VISIBILITY(sym->st_other)) == STV_SINGLETON) 1221 ofl->ofl_dtflags_1 |= DF_1_SINGLETON; 1222 1223 /* 1224 * If building a shared object or executable, and this is a 1225 * non-weak UNDEF symbol with reduced visibility (STV_*), then 1226 * give a fatal error. 1227 */ 1228 if (((oflags & FLG_OF_RELOBJ) == 0) && 1229 (sym->st_shndx == SHN_UNDEF) && 1230 (ELF_ST_BIND(sym->st_info) != STB_WEAK)) { 1231 if (vis && (vis != STV_SINGLETON)) { 1232 sym_undef_entry(ofl, sdp, BNDLOCAL); 1233 ofl->ofl_flags |= FLG_OF_FATAL; 1234 continue; 1235 } 1236 } 1237 1238 /* 1239 * If this symbol is defined in a non-allocatable section, 1240 * reduce it to local symbol. 1241 */ 1242 if (((isp = sdp->sd_isc) != 0) && isp->is_shdr && 1243 ((isp->is_shdr->sh_flags & SHF_ALLOC) == 0)) { 1244 sdp->sd_flags |= FLG_SY_REDUCED; 1245 sdp->sd_flags1 |= FLG_SY1_HIDDEN; 1246 } 1247 1248 /* 1249 * If this symbol originated as a SHN_SUNW_IGNORE, it will have 1250 * been processed as an SHN_UNDEF. Return the symbol to its 1251 * original index for validation, and propagation to the output 1252 * file. 1253 */ 1254 if (sdp->sd_flags1 & FLG_SY1_IGNORE) 1255 sdp->sd_shndx = SHN_SUNW_IGNORE; 1256 1257 if (undef) { 1258 /* 1259 * If a non-weak reference remains undefined, or if a 1260 * mapfile reference is not bound to the relocatable 1261 * objects that make up the object being built, we have 1262 * a fatal error. 1263 * 1264 * The exceptions are symbols which are defined to be 1265 * found in the parent (FLG_SY_PARENT), which is really 1266 * only meaningful for direct binding, or are defined 1267 * external (FLG_SY_EXTERN) so as to suppress -zdefs 1268 * errors. 1269 * 1270 * Register symbols are always allowed to be UNDEF. 1271 * 1272 * Note that we don't include references created via -u 1273 * in the same shared object binding test. This is for 1274 * backward compatibility, in that a number of archive 1275 * makefile rules used -u to cause archive extraction. 1276 * These same rules have been cut and pasted to apply 1277 * to shared objects, and thus although the -u reference 1278 * is redundant, flagging it as fatal could cause some 1279 * build to fail. Also we have documented the use of 1280 * -u as a mechanism to cause binding to weak version 1281 * definitions, thus giving users an error condition 1282 * would be incorrect. 1283 */ 1284 if (!(sdp->sd_flags & FLG_SY_REGSYM) && 1285 ((sym->st_shndx == SHN_UNDEF) && 1286 ((ELF_ST_BIND(sym->st_info) != STB_WEAK) && 1287 ((sdp->sd_flags & 1288 (FLG_SY_PARENT | FLG_SY_EXTERN)) == 0)) || 1289 (((sdp->sd_flags & 1290 (FLG_SY_MAPREF | FLG_SY_MAPUSED)) == 1291 FLG_SY_MAPREF) && 1292 ((sdp->sd_flags1 & (FLG_SY1_HIDDEN | 1293 FLG_SY1_PROTECT)) == 0)))) { 1294 sym_undef_entry(ofl, sdp, UNDEF); 1295 ofl->ofl_flags |= undef; 1296 undeferr = 1; 1297 } 1298 1299 } else { 1300 /* 1301 * For building things like shared objects (or anything 1302 * -znodefs), undefined symbols are allowed. 1303 * 1304 * If a mapfile reference remains undefined the user 1305 * would probably like a warning at least (they've 1306 * usually mis-spelt the reference). Refer to the above 1307 * comments for discussion on -u references, which 1308 * are not tested for in the same manner. 1309 */ 1310 if ((sdp->sd_flags & 1311 (FLG_SY_MAPREF | FLG_SY_MAPUSED)) == 1312 FLG_SY_MAPREF) { 1313 sym_undef_entry(ofl, sdp, UNDEF); 1314 ofl->ofl_flags |= FLG_OF_WARN; 1315 undeferr = 1; 1316 } 1317 } 1318 1319 /* 1320 * If this symbol comes from a dependency mark the dependency 1321 * as required (-z ignore can result in unused dependencies 1322 * being dropped). If we need to record dependency versioning 1323 * information indicate what version of the needed shared object 1324 * this symbol is part of. Flag the symbol as undefined if it 1325 * has not been made available to us. 1326 */ 1327 if ((sdp->sd_ref == REF_DYN_NEED) && 1328 (!(sdp->sd_flags & FLG_SY_REFRSD))) { 1329 sdp->sd_file->ifl_flags |= FLG_IF_DEPREQD; 1330 1331 /* 1332 * Capture that we've bound to a symbol that doesn't 1333 * allow being directly bound to. 1334 */ 1335 if (sdp->sd_flags1 & FLG_SY1_NDIR) 1336 ofl->ofl_flags1 |= FLG_OF1_NDIRECT; 1337 1338 if (sdp->sd_file->ifl_vercnt) { 1339 int vndx; 1340 Ver_index *vip; 1341 1342 vndx = sdp->sd_aux->sa_dverndx; 1343 vip = &sdp->sd_file->ifl_verndx[vndx]; 1344 if (vip->vi_flags & FLG_VER_AVAIL) { 1345 vip->vi_flags |= FLG_VER_REFER; 1346 } else { 1347 sym_undef_entry(ofl, sdp, NOTAVAIL); 1348 ofl->ofl_flags |= FLG_OF_FATAL; 1349 continue; 1350 } 1351 } 1352 } 1353 1354 /* 1355 * Test that we do not bind to symbol supplied from an implicit 1356 * shared object. If a binding is from a weak reference it can 1357 * be ignored. 1358 */ 1359 if (needed && !undeferr && (sdp->sd_flags & FLG_SY_GLOBREF) && 1360 (sdp->sd_ref == REF_DYN_NEED) && 1361 (sdp->sd_flags & FLG_SY_NOTAVAIL)) { 1362 sym_undef_entry(ofl, sdp, IMPLICIT); 1363 ofl->ofl_flags |= needed; 1364 continue; 1365 } 1366 1367 /* 1368 * Test that a symbol isn't going to be reduced to local scope 1369 * which actually wants to bind to a shared object - if so it's 1370 * a fatal error. 1371 */ 1372 if ((sdp->sd_ref == REF_DYN_NEED) && 1373 (sdp->sd_flags1 & (FLG_SY1_HIDDEN | FLG_SY1_PROTECT))) { 1374 sym_undef_entry(ofl, sdp, BNDLOCAL); 1375 ofl->ofl_flags |= FLG_OF_FATAL; 1376 continue; 1377 } 1378 1379 /* 1380 * If the output image is to be versioned then all symbol 1381 * definitions must be associated with a version. 1382 */ 1383 if (verdesc && (sdp->sd_ref == REF_REL_NEED) && 1384 (sym->st_shndx != SHN_UNDEF) && 1385 (!(sdp->sd_flags1 & FLG_SY1_HIDDEN)) && 1386 (sdp->sd_aux->sa_overndx == 0)) { 1387 sym_undef_entry(ofl, sdp, NOVERSION); 1388 ofl->ofl_flags |= verdesc; 1389 continue; 1390 } 1391 1392 /* 1393 * If we don't need the symbol there's no need to process it 1394 * any further. 1395 */ 1396 if (sdp->sd_ref == REF_DYN_SEEN) 1397 continue; 1398 1399 /* 1400 * Calculate the size and alignment requirements for the global 1401 * .bss and .tls sections. If we're building a relocatable 1402 * object only account for scoped COMMON symbols (these will 1403 * be converted to .bss references). 1404 * 1405 * When -z nopartial is in effect, partially initialized 1406 * symbols are directed to the special .data section 1407 * created for that purpose (ofl->ofl_isparexpn). 1408 * Otherwise, partially initialized symbols go to .bss. 1409 * 1410 * Also refer to make_mvsections() in sunwmove.c 1411 */ 1412 if ((sym->st_shndx == SHN_COMMON) && 1413 (((oflags & FLG_OF_RELOBJ) == 0) || 1414 ((sdp->sd_flags1 & FLG_SY1_HIDDEN) && 1415 (oflags & FLG_OF_PROCRED)))) { 1416 if ((sdp->sd_move == NULL) || 1417 ((sdp->sd_flags & FLG_SY_PAREXPN) == 0)) { 1418 Xword * size, * align; 1419 1420 if (type != STT_TLS) { 1421 size = &bsssize; 1422 align = &bssalign; 1423 } else { 1424 size = &tlssize; 1425 align = &tlsalign; 1426 } 1427 *size = (Xword)S_ROUND(*size, sym->st_value) + 1428 sym->st_size; 1429 if (sym->st_value > *align) 1430 *align = sym->st_value; 1431 } 1432 } 1433 1434 #if defined(_ELF64) 1435 /* 1436 * Calculate the size and alignment requirement for the global 1437 * .lbss. TLS or partially initialized symbols do not need to be 1438 * considered yet. 1439 */ 1440 if ((ld_targ.t_m.m_mach == EM_AMD64) && 1441 (sym->st_shndx == SHN_X86_64_LCOMMON)) { 1442 lbsssize = (Xword)S_ROUND(lbsssize, sym->st_value) + 1443 sym->st_size; 1444 if (sym->st_value > lbssalign) 1445 lbssalign = sym->st_value; 1446 } 1447 #endif 1448 1449 /* 1450 * If a symbol was referenced via the command line 1451 * (ld -u <>, ...), then this counts as a reference against the 1452 * symbol. Mark any section that symbol is defined in. 1453 */ 1454 if (((isp = sdp->sd_isc) != 0) && 1455 (sdp->sd_flags & FLG_SY_CMDREF)) { 1456 isp->is_flags |= FLG_IS_SECTREF; 1457 isp->is_file->ifl_flags |= FLG_IF_FILEREF; 1458 } 1459 1460 /* 1461 * Update the symbol count and the associated name string size. 1462 */ 1463 if ((sdp->sd_flags1 & FLG_SY1_HIDDEN) && 1464 (oflags & FLG_OF_PROCRED)) { 1465 /* 1466 * If any reductions are being processed, keep a count 1467 * of eliminated symbols, and if the symbol is being 1468 * reduced to local, count it's size for the .symtab. 1469 */ 1470 if (sdp->sd_flags1 & FLG_SY1_ELIM) { 1471 ofl->ofl_elimcnt++; 1472 } else { 1473 ofl->ofl_scopecnt++; 1474 if ((((sdp->sd_flags & FLG_SY_REGSYM) == 0) || 1475 sym->st_name) && (st_insert(ofl->ofl_strtab, 1476 sdp->sd_name) == -1)) 1477 return (S_ERROR); 1478 if (allow_ldynsym && sym->st_name && 1479 ldynsym_symtype[type]) { 1480 ofl->ofl_dynscopecnt++; 1481 if (st_insert(ofl->ofl_dynstrtab, 1482 sdp->sd_name) == -1) 1483 return (S_ERROR); 1484 /* Include it in sort section? */ 1485 DYNSORT_COUNT(sdp, sym, type, ++); 1486 } 1487 } 1488 } else { 1489 ofl->ofl_globcnt++; 1490 1491 /* 1492 * Check to see if this global variable should 1493 * go into a sort section. Sort sections require 1494 * a .SUNW_ldynsym section, so, don't check 1495 * unless a .SUNW_ldynsym is allowed. 1496 */ 1497 if (allow_ldynsym) { 1498 DYNSORT_COUNT(sdp, sym, type, ++); 1499 } 1500 1501 /* 1502 * If global direct bindings are in effect, or this 1503 * symbol has bound to a dependency which was specified 1504 * as requiring direct bindings, and it hasn't 1505 * explicitly been defined as a non-direct binding 1506 * symbol, mark it. 1507 */ 1508 if (((ofl->ofl_dtflags_1 & DF_1_DIRECT) || (isp && 1509 (isp->is_file->ifl_flags & FLG_IF_DIRECT))) && 1510 ((sdp->sd_flags1 & FLG_SY1_NDIR) == 0)) 1511 sdp->sd_flags1 |= FLG_SY1_DIR; 1512 1513 /* 1514 * Insert the symbol name. 1515 */ 1516 if (((sdp->sd_flags & FLG_SY_REGSYM) == 0) || 1517 sym->st_name) { 1518 if (st_insert(ofl->ofl_strtab, 1519 sdp->sd_name) == -1) 1520 return (S_ERROR); 1521 1522 if (!(ofl->ofl_flags & FLG_OF_RELOBJ) && 1523 (st_insert(ofl->ofl_dynstrtab, 1524 sdp->sd_name) == -1)) 1525 return (S_ERROR); 1526 } 1527 1528 /* 1529 * If this section offers a global symbol - record that 1530 * fact. 1531 */ 1532 if (isp) { 1533 isp->is_flags |= FLG_IS_SECTREF; 1534 isp->is_file->ifl_flags |= FLG_IF_FILEREF; 1535 } 1536 } 1537 } 1538 1539 /* 1540 * If we've encountered a fatal error during symbol validation then 1541 * return now. 1542 */ 1543 if (ofl->ofl_flags & FLG_OF_FATAL) 1544 return (1); 1545 1546 /* 1547 * Now that symbol resolution is completed, scan any register symbols. 1548 * From now on, we're only interested in those that contribute to the 1549 * output file. 1550 */ 1551 if (ofl->ofl_regsyms) { 1552 int ndx; 1553 1554 for (ndx = 0; ndx < ofl->ofl_regsymsno; ndx++) { 1555 if ((sdp = ofl->ofl_regsyms[ndx]) == NULL) 1556 continue; 1557 if (sdp->sd_ref != REF_REL_NEED) { 1558 ofl->ofl_regsyms[ndx] = NULL; 1559 continue; 1560 } 1561 1562 ofl->ofl_regsymcnt++; 1563 if (sdp->sd_sym->st_name == 0) 1564 sdp->sd_name = MSG_ORIG(MSG_STR_EMPTY); 1565 1566 if ((sdp->sd_flags1 & FLG_SY1_HIDDEN) || 1567 (ELF_ST_BIND(sdp->sd_sym->st_info) == STB_LOCAL)) 1568 ofl->ofl_lregsymcnt++; 1569 } 1570 } 1571 1572 /* 1573 * Generate the .bss section now that we know its size and alignment. 1574 */ 1575 if (bsssize) { 1576 if (ld_make_bss(ofl, bsssize, bssalign, 1577 ld_targ.t_id.id_bss) == S_ERROR) 1578 return (S_ERROR); 1579 } 1580 if (tlssize) { 1581 if (ld_make_bss(ofl, tlssize, tlsalign, 1582 ld_targ.t_id.id_tlsbss) == S_ERROR) 1583 return (S_ERROR); 1584 } 1585 #if defined(_ELF64) 1586 if ((ld_targ.t_m.m_mach == EM_AMD64) && 1587 lbsssize && !(oflags & FLG_OF_RELOBJ)) { 1588 if (ld_make_bss(ofl, lbsssize, lbssalign, 1589 ld_targ.t_id.id_lbss) == S_ERROR) 1590 return (S_ERROR); 1591 } 1592 #endif 1593 /* 1594 * Determine what entry point symbol we need, and if found save its 1595 * symbol descriptor so that we can update the ELF header entry with the 1596 * symbols value later (see update_oehdr). Make sure the symbol is 1597 * tagged to ensure its update in case -s is in effect. Use any -e 1598 * option first, or the default entry points `_start' and `main'. 1599 */ 1600 ret = 0; 1601 if (ofl->ofl_entry) { 1602 if ((sdp = 1603 ld_sym_find(ofl->ofl_entry, SYM_NOHASH, 0, ofl)) == NULL) { 1604 eprintf(ofl->ofl_lml, ERR_FATAL, 1605 MSG_INTL(MSG_ARG_NOENTRY), ofl->ofl_entry); 1606 ret++; 1607 } else if (ensure_sym_local(ofl, sdp, 1608 MSG_INTL(MSG_SYM_ENTRY)) != 0) { 1609 ret++; 1610 } else { 1611 ofl->ofl_entry = (void *)sdp; 1612 } 1613 } else if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_START), 1614 SYM_NOHASH, 0, ofl)) != NULL) && (ensure_sym_local(ofl, 1615 sdp, 0) == 0)) { 1616 ofl->ofl_entry = (void *)sdp; 1617 1618 } else if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_MAIN), 1619 SYM_NOHASH, 0, ofl)) != NULL) && (ensure_sym_local(ofl, 1620 sdp, 0) == 0)) { 1621 ofl->ofl_entry = (void *)sdp; 1622 } 1623 1624 /* 1625 * If ld -zdtrace=<sym> was given, then validate that the symbol is 1626 * defined within the current object being built. 1627 */ 1628 if ((sdp = ofl->ofl_dtracesym) != 0) 1629 ret += ensure_sym_local(ofl, sdp, MSG_ORIG(MSG_STR_DTRACE)); 1630 1631 /* 1632 * If any initarray, finiarray or preinitarray functions have been 1633 * requested, make sure they are defined within the current object 1634 * being built. 1635 */ 1636 if (ofl->ofl_initarray) { 1637 ret += ensure_array_local(ofl, ofl->ofl_initarray, 1638 MSG_ORIG(MSG_SYM_INITARRAY)); 1639 } 1640 if (ofl->ofl_finiarray) { 1641 ret += ensure_array_local(ofl, ofl->ofl_finiarray, 1642 MSG_ORIG(MSG_SYM_FINIARRAY)); 1643 } 1644 if (ofl->ofl_preiarray) { 1645 ret += ensure_array_local(ofl, ofl->ofl_preiarray, 1646 MSG_ORIG(MSG_SYM_PREINITARRAY)); 1647 } 1648 1649 if (ret) 1650 return (S_ERROR); 1651 1652 /* 1653 * If we're required to record any needed dependencies versioning 1654 * information calculate it now that all symbols have been validated. 1655 */ 1656 if ((oflags & (FLG_OF_VERNEED | FLG_OF_NOVERSEC)) == FLG_OF_VERNEED) 1657 return (ld_vers_check_need(ofl)); 1658 else 1659 return (1); 1660 } 1661 1662 /* 1663 * qsort(3c) comparison function. As an optimization for associating weak 1664 * symbols to their strong counterparts sort global symbols according to their 1665 * section index, address and binding. 1666 */ 1667 static int 1668 compare(const void *sdpp1, const void *sdpp2) 1669 { 1670 Sym_desc *sdp1 = *((Sym_desc **)sdpp1); 1671 Sym_desc *sdp2 = *((Sym_desc **)sdpp2); 1672 Sym *sym1, *sym2; 1673 uchar_t bind1, bind2; 1674 1675 /* 1676 * Symbol descriptors may be zero, move these to the front of the 1677 * sorted array. 1678 */ 1679 if (sdp1 == NULL) 1680 return (-1); 1681 if (sdp2 == NULL) 1682 return (1); 1683 1684 sym1 = sdp1->sd_sym; 1685 sym2 = sdp2->sd_sym; 1686 1687 /* 1688 * Compare the symbols section index. This is important when sorting 1689 * the symbol tables of relocatable objects. In this case, a symbols 1690 * value is the offset within the associated section, and thus many 1691 * symbols can have the same value, but are effectively different 1692 * addresses. 1693 */ 1694 if (sym1->st_shndx > sym2->st_shndx) 1695 return (1); 1696 if (sym1->st_shndx < sym2->st_shndx) 1697 return (-1); 1698 1699 /* 1700 * Compare the symbols value (address). 1701 */ 1702 if (sym1->st_value > sym2->st_value) 1703 return (1); 1704 if (sym1->st_value < sym2->st_value) 1705 return (-1); 1706 1707 bind1 = ELF_ST_BIND(sym1->st_info); 1708 bind2 = ELF_ST_BIND(sym2->st_info); 1709 1710 /* 1711 * If two symbols have the same address place the weak symbol before 1712 * any strong counterpart. 1713 */ 1714 if (bind1 > bind2) 1715 return (-1); 1716 if (bind1 < bind2) 1717 return (1); 1718 1719 return (0); 1720 } 1721 1722 /* 1723 * Issue a MSG_SYM_BADADDR error from ld_sym_process(). This error 1724 * is issued when a symbol address/size is not contained by the 1725 * target section. 1726 * 1727 * Such objects are at least partially corrupt, and the user would 1728 * be well advised to be skeptical of them, and to ask their compiler 1729 * supplier to fix the problem. However, a distinction needs to be 1730 * made between symbols that reference readonly text, and those that 1731 * access writable data. Other than throwing off profiling results, 1732 * the readonly section case is less serious. We have encountered 1733 * such objects in the field. In order to allow existing objects 1734 * to continue working, we issue a warning rather than a fatal error 1735 * if the symbol is against readonly text. Other cases are fatal. 1736 */ 1737 static void 1738 issue_badaddr_msg(Ifl_desc *ifl, Ofl_desc *ofl, Sym_desc *sdp, 1739 Sym *sym, Word shndx) 1740 { 1741 ofl_flag_t flag; 1742 Error err; 1743 const char *msg; 1744 1745 if ((sdp->sd_isc->is_shdr->sh_flags & (SHF_WRITE | SHF_ALLOC)) == 1746 SHF_ALLOC) { 1747 msg = MSG_INTL(MSG_SYM_BADADDR_ROTXT); 1748 flag = FLG_OF_WARN; 1749 err = ERR_WARNING; 1750 } else { 1751 msg = MSG_INTL(MSG_SYM_BADADDR); 1752 flag = FLG_OF_FATAL; 1753 err = ERR_FATAL; 1754 } 1755 1756 eprintf(ofl->ofl_lml, err, msg, demangle(sdp->sd_name), 1757 ifl->ifl_name, shndx, sdp->sd_isc->is_name, 1758 EC_XWORD(sdp->sd_isc->is_shdr->sh_size), 1759 EC_XWORD(sym->st_value), EC_XWORD(sym->st_size)); 1760 ofl->ofl_flags |= flag; 1761 } 1762 1763 1764 /* 1765 * Process the symbol table for the specified input file. At this point all 1766 * input sections from this input file have been assigned an input section 1767 * descriptor which is saved in the `ifl_isdesc' array. 1768 * 1769 * - local symbols are saved (as is) if the input file is a 1770 * relocatable object 1771 * 1772 * - global symbols are added to the linkers internal symbol 1773 * table if they are not already present, otherwise a symbol 1774 * resolution function is called upon to resolve the conflict. 1775 */ 1776 uintptr_t 1777 ld_sym_process(Is_desc *isc, Ifl_desc *ifl, Ofl_desc *ofl) 1778 { 1779 /* 1780 * This macro tests the given symbol to see if it is out of 1781 * range relative to the section it references. 1782 * 1783 * entry: 1784 * - ifl is a relative object (ET_REL) 1785 * _sdp - Symbol descriptor 1786 * _sym - Symbol 1787 * _type - Symbol type 1788 * 1789 * The following are tested: 1790 * - Symbol length is non-zero 1791 * - Symbol type is a type that references code or data 1792 * - Referenced section is not 0 (indicates an UNDEF symbol) 1793 * and is not in the range of special values above SHN_LORESERVE 1794 * (excluding SHN_XINDEX, which is OK). 1795 * - We have a valid section header for the target section 1796 * 1797 * If the above are all true, and the symbol position is not 1798 * contained by the target section, this macro evaluates to 1799 * True (1). Otherwise, False(0). 1800 */ 1801 #define SYM_LOC_BADADDR(_sdp, _sym, _type) \ 1802 (_sym->st_size && dynsymsort_symtype[_type] && \ 1803 (_sym->st_shndx != SHN_UNDEF) && \ 1804 ((_sym->st_shndx < SHN_LORESERVE) || \ 1805 (_sym->st_shndx == SHN_XINDEX)) && \ 1806 _sdp->sd_isc && _sdp->sd_isc->is_shdr && \ 1807 ((_sym->st_value + _sym->st_size) > _sdp->sd_isc->is_shdr->sh_size)) 1808 1809 Conv_inv_buf_t inv_buf; 1810 Sym *sym = (Sym *)isc->is_indata->d_buf; 1811 Word *symshndx = NULL; 1812 Shdr *shdr = isc->is_shdr; 1813 Sym_desc *sdp; 1814 size_t strsize; 1815 char *strs; 1816 uchar_t type, bind; 1817 Word ndx, hash, local, total; 1818 Half etype = ifl->ifl_ehdr->e_type; 1819 int etype_rel; 1820 const char *symsecname, *strsecname; 1821 avl_index_t where; 1822 int test_gnu_hidden_bit, weak; 1823 1824 /* 1825 * Its possible that a file may contain more that one symbol table, 1826 * ie. .dynsym and .symtab in a shared library. Only process the first 1827 * table (here, we assume .dynsym comes before .symtab). 1828 */ 1829 if (ifl->ifl_symscnt) 1830 return (1); 1831 1832 if (isc->is_symshndx) 1833 symshndx = isc->is_symshndx->is_indata->d_buf; 1834 1835 DBG_CALL(Dbg_syms_process(ofl->ofl_lml, ifl)); 1836 1837 if (isc->is_name) 1838 symsecname = isc->is_name; 1839 else 1840 symsecname = MSG_ORIG(MSG_STR_EMPTY); 1841 1842 /* 1843 * From the symbol tables section header information determine which 1844 * strtab table is needed to locate the actual symbol names. 1845 */ 1846 if (ifl->ifl_flags & FLG_IF_HSTRTAB) { 1847 ndx = shdr->sh_link; 1848 if ((ndx == 0) || (ndx >= ifl->ifl_shnum)) { 1849 eprintf(ofl->ofl_lml, ERR_FATAL, 1850 MSG_INTL(MSG_FIL_INVSHLINK), 1851 ifl->ifl_name, symsecname, EC_XWORD(ndx)); 1852 return (S_ERROR); 1853 } 1854 strsize = ifl->ifl_isdesc[ndx]->is_shdr->sh_size; 1855 strs = ifl->ifl_isdesc[ndx]->is_indata->d_buf; 1856 if (ifl->ifl_isdesc[ndx]->is_name) 1857 strsecname = ifl->ifl_isdesc[ndx]->is_name; 1858 else 1859 strsecname = MSG_ORIG(MSG_STR_EMPTY); 1860 } else { 1861 /* 1862 * There is no string table section in this input file 1863 * although there are symbols in this symbol table section. 1864 * This means that these symbols do not have names. 1865 * Currently, only scratch register symbols are allowed 1866 * not to have names. 1867 */ 1868 strsize = 0; 1869 strs = (char *)MSG_ORIG(MSG_STR_EMPTY); 1870 strsecname = MSG_ORIG(MSG_STR_EMPTY); 1871 } 1872 1873 /* 1874 * Determine the number of local symbols together with the total 1875 * number we have to process. 1876 */ 1877 total = (Word)(shdr->sh_size / shdr->sh_entsize); 1878 local = shdr->sh_info; 1879 1880 /* 1881 * Allocate a symbol table index array and a local symbol array 1882 * (global symbols are processed and added to the ofl->ofl_symbkt[] 1883 * array). If we are dealing with a relocatable object, allocate the 1884 * local symbol descriptors. If this isn't a relocatable object we 1885 * still have to process any shared object locals to determine if any 1886 * register symbols exist. Although these aren't added to the output 1887 * image, they are used as part of symbol resolution. 1888 */ 1889 if ((ifl->ifl_oldndx = libld_malloc((size_t)(total * 1890 sizeof (Sym_desc *)))) == NULL) 1891 return (S_ERROR); 1892 etype_rel = (etype == ET_REL); 1893 if (etype_rel && local) { 1894 if ((ifl->ifl_locs = 1895 libld_calloc(sizeof (Sym_desc), local)) == NULL) 1896 return (S_ERROR); 1897 /* LINTED */ 1898 ifl->ifl_locscnt = (Word)local; 1899 } 1900 ifl->ifl_symscnt = total; 1901 1902 /* 1903 * If there are local symbols to save add them to the symbol table 1904 * index array. 1905 */ 1906 if (local) { 1907 int allow_ldynsym = OFL_ALLOW_LDYNSYM(ofl); 1908 Sym_desc *last_file_sdp = NULL; 1909 int last_file_ndx = 0; 1910 1911 for (sym++, ndx = 1; ndx < local; sym++, ndx++) { 1912 Word shndx, sdflags = FLG_SY_CLEAN; 1913 const char *name; 1914 Sym_desc *rsdp; 1915 int shndx_bad = 0; 1916 int symtab_enter = 1; 1917 1918 /* 1919 * Determine and validate the associated section index. 1920 */ 1921 if (symshndx && (sym->st_shndx == SHN_XINDEX)) { 1922 shndx = symshndx[ndx]; 1923 } else if ((shndx = sym->st_shndx) >= SHN_LORESERVE) { 1924 sdflags |= FLG_SY_SPECSEC; 1925 } else if (shndx > ifl->ifl_ehdr->e_shnum) { 1926 /* We need the name before we can issue error */ 1927 shndx_bad = 1; 1928 } 1929 1930 /* 1931 * Check if st_name has a valid value or not. 1932 */ 1933 if ((name = string(ofl, ifl, sym, strs, strsize, ndx, 1934 shndx, symsecname, strsecname, &sdflags)) == NULL) { 1935 ofl->ofl_flags |= FLG_OF_FATAL; 1936 continue; 1937 } 1938 1939 /* 1940 * Now that we have the name, if the section index 1941 * was bad, report it. 1942 */ 1943 if (shndx_bad) { 1944 eprintf(ofl->ofl_lml, ERR_WARNING, 1945 MSG_INTL(MSG_SYM_INVSHNDX), 1946 demangle_symname(name, isc->is_name, ndx), 1947 ifl->ifl_name, 1948 conv_sym_shndx(sym->st_shndx, &inv_buf)); 1949 continue; 1950 } 1951 1952 /* 1953 * If this local symbol table originates from a shared 1954 * object, then we're only interested in recording 1955 * register symbols. As local symbol descriptors aren't 1956 * allocated for shared objects, one will be allocated 1957 * to associated with the register symbol. This symbol 1958 * won't become part of the output image, but we must 1959 * process it to test for register conflicts. 1960 */ 1961 rsdp = sdp = 0; 1962 if (sdflags & FLG_SY_REGSYM) { 1963 /* 1964 * The presence of FLG_SY_REGSYM means that 1965 * the pointers in ld_targ.t_ms are non-NULL. 1966 */ 1967 rsdp = (*ld_targ.t_ms.ms_reg_find)(sym, ofl); 1968 if (rsdp != 0) { 1969 /* 1970 * The fact that another register def- 1971 * inition has been found is fatal. 1972 * Call the verification routine to get 1973 * the error message and move on. 1974 */ 1975 (void) (*ld_targ.t_ms.ms_reg_check) 1976 (rsdp, sym, name, ifl, ofl); 1977 continue; 1978 } 1979 1980 if (etype == ET_DYN) { 1981 if ((sdp = libld_calloc( 1982 sizeof (Sym_desc), 1)) == NULL) 1983 return (S_ERROR); 1984 sdp->sd_ref = REF_DYN_SEEN; 1985 1986 /* Will not appear in output object */ 1987 symtab_enter = 0; 1988 } 1989 } else if (etype == ET_DYN) 1990 continue; 1991 1992 /* 1993 * Fill in the remaining symbol descriptor information. 1994 */ 1995 if (sdp == NULL) { 1996 sdp = &(ifl->ifl_locs[ndx]); 1997 sdp->sd_ref = REF_REL_NEED; 1998 } 1999 if (rsdp == NULL) { 2000 sdp->sd_name = name; 2001 sdp->sd_sym = sym; 2002 sdp->sd_shndx = shndx; 2003 sdp->sd_flags = sdflags; 2004 sdp->sd_file = ifl; 2005 ifl->ifl_oldndx[ndx] = sdp; 2006 } 2007 2008 DBG_CALL(Dbg_syms_entry(ofl->ofl_lml, ndx, sdp)); 2009 2010 /* 2011 * Reclassify any SHN_SUNW_IGNORE symbols to SHN_UNDEF 2012 * so as to simplify future processing. 2013 */ 2014 if (sym->st_shndx == SHN_SUNW_IGNORE) { 2015 sdp->sd_shndx = shndx = SHN_UNDEF; 2016 sdp->sd_flags1 |= 2017 (FLG_SY1_IGNORE | FLG_SY1_ELIM); 2018 } 2019 2020 /* 2021 * Process any register symbols. 2022 */ 2023 if (sdp->sd_flags & FLG_SY_REGSYM) { 2024 /* 2025 * Add a diagnostic to indicate we've caught a 2026 * register symbol, as this can be useful if a 2027 * register conflict is later discovered. 2028 */ 2029 DBG_CALL(Dbg_syms_entered(ofl, sym, sdp)); 2030 2031 /* 2032 * If this register symbol hasn't already been 2033 * recorded, enter it now. 2034 * 2035 * The presence of FLG_SY_REGSYM means that 2036 * the pointers in ld_targ.t_ms are non-NULL. 2037 */ 2038 if ((rsdp == NULL) && 2039 ((*ld_targ.t_ms.ms_reg_enter)(sdp, ofl) == 2040 0)) 2041 return (S_ERROR); 2042 } 2043 2044 /* 2045 * Assign an input section. 2046 */ 2047 if ((sym->st_shndx != SHN_UNDEF) && 2048 ((sdp->sd_flags & FLG_SY_SPECSEC) == 0)) 2049 sdp->sd_isc = ifl->ifl_isdesc[shndx]; 2050 2051 /* 2052 * If this symbol falls within the range of a section 2053 * being discarded, then discard the symbol itself. 2054 * There is no reason to keep this local symbol. 2055 */ 2056 if (sdp->sd_isc && 2057 (sdp->sd_isc->is_flags & FLG_IS_DISCARD)) { 2058 sdp->sd_flags |= FLG_SY_ISDISC; 2059 DBG_CALL(Dbg_syms_discarded(ofl->ofl_lml, sdp)); 2060 continue; 2061 } 2062 2063 /* 2064 * Skip any section symbols as new versions of these 2065 * will be created. 2066 */ 2067 if ((type = ELF_ST_TYPE(sym->st_info)) == STT_SECTION) { 2068 if (sym->st_shndx == SHN_UNDEF) { 2069 eprintf(ofl->ofl_lml, ERR_WARNING, 2070 MSG_INTL(MSG_SYM_INVSHNDX), 2071 demangle_symname(name, isc->is_name, 2072 ndx), ifl->ifl_name, 2073 conv_sym_shndx(sym->st_shndx, 2074 &inv_buf)); 2075 } 2076 continue; 2077 } 2078 2079 /* 2080 * For a relocatable object, if this symbol is defined 2081 * and has non-zero length and references an address 2082 * within an associated section, then check its extents 2083 * to make sure the section boundaries encompass it. 2084 * If they don't, the ELF file is corrupt. 2085 */ 2086 if (etype_rel) { 2087 if (SYM_LOC_BADADDR(sdp, sym, type)) { 2088 issue_badaddr_msg(ifl, ofl, sdp, 2089 sym, shndx); 2090 if (ofl->ofl_flags & FLG_OF_FATAL) 2091 continue; 2092 } 2093 2094 /* 2095 * We have observed relocatable objects 2096 * containing identical adjacent STT_FILE 2097 * symbols. Discard any other than the first, 2098 * as they are all equivalent and the extras 2099 * do not add information. 2100 * 2101 * For the purpose of this test, we assume 2102 * that only the symbol type and the string 2103 * table offset (st_name) matter. 2104 */ 2105 if (type == STT_FILE) { 2106 int toss = (last_file_sdp != NULL) && 2107 ((ndx - 1) == last_file_ndx) && 2108 (sym->st_name == 2109 last_file_sdp->sd_sym->st_name); 2110 2111 last_file_sdp = sdp; 2112 last_file_ndx = ndx; 2113 if (toss) { 2114 sdp->sd_flags |= FLG_SY_INVALID; 2115 DBG_CALL(Dbg_syms_dup_discarded( 2116 ofl->ofl_lml, ndx, sdp)); 2117 continue; 2118 } 2119 } 2120 } 2121 2122 2123 /* 2124 * Sanity check for TLS 2125 */ 2126 if ((sym->st_size != 0) && ((type == STT_TLS) && 2127 (sym->st_shndx != SHN_COMMON))) { 2128 Is_desc *isp = sdp->sd_isc; 2129 2130 if ((isp == NULL) || (isp->is_shdr == NULL) || 2131 ((isp->is_shdr->sh_flags & SHF_TLS) == 0)) { 2132 eprintf(ofl->ofl_lml, ERR_FATAL, 2133 MSG_INTL(MSG_SYM_TLS), 2134 demangle(sdp->sd_name), 2135 ifl->ifl_name); 2136 ofl->ofl_flags |= FLG_OF_FATAL; 2137 continue; 2138 } 2139 } 2140 2141 /* 2142 * Carry our some basic sanity checks (these are just 2143 * some of the erroneous symbol entries we've come 2144 * across, there's probably a lot more). The symbol 2145 * will not be carried forward to the output file, which 2146 * won't be a problem unless a relocation is required 2147 * against it. 2148 */ 2149 if (((sdp->sd_flags & FLG_SY_SPECSEC) && 2150 ((sym->st_shndx == SHN_COMMON)) || 2151 ((type == STT_FILE) && 2152 (sym->st_shndx != SHN_ABS))) || 2153 (sdp->sd_isc && (sdp->sd_isc->is_osdesc == NULL))) { 2154 eprintf(ofl->ofl_lml, ERR_WARNING, 2155 MSG_INTL(MSG_SYM_INVSHNDX), 2156 demangle_symname(name, isc->is_name, ndx), 2157 ifl->ifl_name, 2158 conv_sym_shndx(sym->st_shndx, &inv_buf)); 2159 sdp->sd_isc = NULL; 2160 sdp->sd_flags |= FLG_SY_INVALID; 2161 continue; 2162 } 2163 2164 /* 2165 * As these local symbols will become part of the output 2166 * image, record their number and name string size. 2167 * Globals are counted after all input file processing 2168 * (and hence symbol resolution) is complete during 2169 * sym_validate(). 2170 */ 2171 if (!(ofl->ofl_flags & FLG_OF_REDLSYM) && 2172 symtab_enter) { 2173 ofl->ofl_locscnt++; 2174 2175 if ((((sdp->sd_flags & FLG_SY_REGSYM) == 0) || 2176 sym->st_name) && (st_insert(ofl->ofl_strtab, 2177 sdp->sd_name) == -1)) 2178 return (S_ERROR); 2179 2180 if (allow_ldynsym && sym->st_name && 2181 ldynsym_symtype[type]) { 2182 ofl->ofl_dynlocscnt++; 2183 if (st_insert(ofl->ofl_dynstrtab, 2184 sdp->sd_name) == -1) 2185 return (S_ERROR); 2186 /* Include it in sort section? */ 2187 DYNSORT_COUNT(sdp, sym, type, ++); 2188 } 2189 } 2190 } 2191 } 2192 2193 /* 2194 * The GNU ld interprets the top bit of the 16-bit Versym value 2195 * (0x8000) as the "hidden" bit. If this bit is set, the linker 2196 * is supposed to act as if that symbol does not exist. The Solaris 2197 * linker does not support this mechanism, or the model of interface 2198 * evolution that it allows, but we honor it in GNU ld produced 2199 * objects in order to interoperate with them. 2200 * 2201 * Determine if we should honor the GNU hidden bit for this file. 2202 */ 2203 test_gnu_hidden_bit = ((ifl->ifl_flags & FLG_IF_GNUVER) != 0) && 2204 (ifl->ifl_versym != NULL); 2205 2206 /* 2207 * Now scan the global symbols entering them in the internal symbol 2208 * table or resolving them as necessary. 2209 */ 2210 sym = (Sym *)isc->is_indata->d_buf; 2211 sym += local; 2212 weak = 0; 2213 /* LINTED */ 2214 for (ndx = (int)local; ndx < total; sym++, ndx++) { 2215 const char *name; 2216 Word shndx, sdflags = 0; 2217 int shndx_bad = 0; 2218 2219 /* 2220 * Determine and validate the associated section index. 2221 */ 2222 if (symshndx && (sym->st_shndx == SHN_XINDEX)) { 2223 shndx = symshndx[ndx]; 2224 } else if ((shndx = sym->st_shndx) >= SHN_LORESERVE) { 2225 sdflags |= FLG_SY_SPECSEC; 2226 } else if (shndx > ifl->ifl_ehdr->e_shnum) { 2227 /* We need the name before we can issue error */ 2228 shndx_bad = 1; 2229 } 2230 2231 /* 2232 * Check if st_name has a valid value or not. 2233 */ 2234 if ((name = string(ofl, ifl, sym, strs, strsize, ndx, shndx, 2235 symsecname, strsecname, &sdflags)) == NULL) { 2236 ofl->ofl_flags |= FLG_OF_FATAL; 2237 continue; 2238 } 2239 2240 /* 2241 * Now that we have the name, if the section index 2242 * was bad, report it. 2243 */ 2244 if (shndx_bad) { 2245 eprintf(ofl->ofl_lml, ERR_WARNING, 2246 MSG_INTL(MSG_SYM_INVSHNDX), 2247 demangle_symname(name, isc->is_name, ndx), 2248 ifl->ifl_name, 2249 conv_sym_shndx(sym->st_shndx, &inv_buf)); 2250 continue; 2251 } 2252 2253 2254 /* 2255 * Test for the GNU hidden bit, and ignore symbols that 2256 * have it set. 2257 */ 2258 if (test_gnu_hidden_bit && 2259 ((ifl->ifl_versym[ndx] & 0x8000) != 0)) 2260 continue; 2261 2262 /* 2263 * The linker itself will generate symbols for _end, _etext, 2264 * _edata, _DYNAMIC and _PROCEDURE_LINKAGE_TABLE_, so don't 2265 * bother entering these symbols from shared objects. This 2266 * results in some wasted resolution processing, which is hard 2267 * to feel, but if nothing else, pollutes diagnostic relocation 2268 * output. 2269 */ 2270 if (name[0] && (etype == ET_DYN) && (sym->st_size == 0) && 2271 (ELF_ST_TYPE(sym->st_info) == STT_OBJECT) && 2272 (name[0] == '_') && ((name[1] == 'e') || 2273 (name[1] == 'D') || (name[1] == 'P')) && 2274 ((strcmp(name, MSG_ORIG(MSG_SYM_ETEXT_U)) == 0) || 2275 (strcmp(name, MSG_ORIG(MSG_SYM_EDATA_U)) == 0) || 2276 (strcmp(name, MSG_ORIG(MSG_SYM_END_U)) == 0) || 2277 (strcmp(name, MSG_ORIG(MSG_SYM_DYNAMIC_U)) == 0) || 2278 (strcmp(name, MSG_ORIG(MSG_SYM_PLKTBL_U)) == 0))) { 2279 ifl->ifl_oldndx[ndx] = 0; 2280 continue; 2281 } 2282 2283 /* 2284 * Determine and validate the symbols binding. 2285 */ 2286 bind = ELF_ST_BIND(sym->st_info); 2287 if ((bind != STB_GLOBAL) && (bind != STB_WEAK)) { 2288 eprintf(ofl->ofl_lml, ERR_WARNING, 2289 MSG_INTL(MSG_SYM_NONGLOB), 2290 demangle_symname(name, isc->is_name, ndx), 2291 ifl->ifl_name, 2292 conv_sym_info_bind(bind, 0, &inv_buf)); 2293 continue; 2294 } 2295 if (bind == STB_WEAK) 2296 weak++; 2297 2298 /* 2299 * If this symbol falls within the range of a section being 2300 * discarded, then discard the symbol itself. 2301 */ 2302 if (((sdflags & FLG_SY_SPECSEC) == 0) && 2303 (sym->st_shndx != SHN_UNDEF)) { 2304 Is_desc *isp; 2305 2306 if (shndx >= ifl->ifl_shnum) { 2307 /* 2308 * Carry our some basic sanity checks 2309 * The symbol will not be carried forward to 2310 * the output file, which won't be a problem 2311 * unless a relocation is required against it. 2312 */ 2313 eprintf(ofl->ofl_lml, ERR_WARNING, 2314 MSG_INTL(MSG_SYM_INVSHNDX), 2315 demangle_symname(name, isc->is_name, ndx), 2316 ifl->ifl_name, 2317 conv_sym_shndx(sym->st_shndx, &inv_buf)); 2318 continue; 2319 } 2320 2321 isp = ifl->ifl_isdesc[shndx]; 2322 if (isp && (isp->is_flags & FLG_IS_DISCARD)) { 2323 if ((sdp = 2324 libld_calloc(sizeof (Sym_desc), 1)) == NULL) 2325 return (S_ERROR); 2326 2327 /* 2328 * Create a dummy symbol entry so that if we 2329 * find any references to this discarded symbol 2330 * we can compensate. 2331 */ 2332 sdp->sd_name = name; 2333 sdp->sd_sym = sym; 2334 sdp->sd_file = ifl; 2335 sdp->sd_isc = isp; 2336 sdp->sd_flags = FLG_SY_ISDISC; 2337 ifl->ifl_oldndx[ndx] = sdp; 2338 2339 DBG_CALL(Dbg_syms_discarded(ofl->ofl_lml, sdp)); 2340 continue; 2341 } 2342 } 2343 2344 /* 2345 * If the symbol does not already exist in the internal symbol 2346 * table add it, otherwise resolve the conflict. If the symbol 2347 * from this file is kept, retain its symbol table index for 2348 * possible use in associating a global alias. 2349 */ 2350 /* LINTED */ 2351 hash = (Word)elf_hash((const char *)name); 2352 if ((sdp = ld_sym_find(name, hash, &where, ofl)) == NULL) { 2353 DBG_CALL(Dbg_syms_global(ofl->ofl_lml, ndx, name)); 2354 if ((sdp = ld_sym_enter(name, sym, hash, ifl, ofl, ndx, 2355 shndx, sdflags, 0, &where)) == (Sym_desc *)S_ERROR) 2356 return (S_ERROR); 2357 2358 } else if (ld_sym_resolve(sdp, sym, ifl, ofl, ndx, shndx, 2359 sdflags) == S_ERROR) 2360 return (S_ERROR); 2361 2362 /* 2363 * After we've compared a defined symbol in one shared 2364 * object, flag the symbol so we don't compare it again. 2365 */ 2366 if ((etype == ET_DYN) && (sym->st_shndx != SHN_UNDEF) && 2367 ((sdp->sd_flags & FLG_SY_SOFOUND) == 0)) 2368 sdp->sd_flags |= FLG_SY_SOFOUND; 2369 2370 /* 2371 * If the symbol is accepted from this file retain the symbol 2372 * index for possible use in aliasing. 2373 */ 2374 if (sdp->sd_file == ifl) 2375 sdp->sd_symndx = ndx; 2376 2377 ifl->ifl_oldndx[ndx] = sdp; 2378 2379 /* 2380 * If we've accepted a register symbol, continue to validate 2381 * it. 2382 */ 2383 if (sdp->sd_flags & FLG_SY_REGSYM) { 2384 Sym_desc *rsdp; 2385 2386 /* 2387 * The presence of FLG_SY_REGSYM means that 2388 * the pointers in ld_targ.t_ms are non-NULL. 2389 */ 2390 rsdp = (*ld_targ.t_ms.ms_reg_find)(sdp->sd_sym, ofl); 2391 if (rsdp == NULL) { 2392 if ((*ld_targ.t_ms.ms_reg_enter)(sdp, ofl) == 0) 2393 return (S_ERROR); 2394 } else if (rsdp != sdp) { 2395 (void) (*ld_targ.t_ms.ms_reg_check)(rsdp, 2396 sdp->sd_sym, sdp->sd_name, ifl, ofl); 2397 } 2398 } 2399 2400 /* 2401 * For a relocatable object, if this symbol is defined 2402 * and has non-zero length and references an address 2403 * within an associated section, then check its extents 2404 * to make sure the section boundaries encompass it. 2405 * If they don't, the ELF file is corrupt. Note that this 2406 * global symbol may have come from another file to satisfy 2407 * an UNDEF symbol of the same name from this one. In that 2408 * case, we don't check it, because it was already checked 2409 * as part of its own file. 2410 */ 2411 if (etype_rel && (sdp->sd_file == ifl)) { 2412 Sym *tsym = sdp->sd_sym; 2413 2414 if (SYM_LOC_BADADDR(sdp, tsym, 2415 ELF_ST_TYPE(tsym->st_info))) { 2416 issue_badaddr_msg(ifl, ofl, sdp, 2417 tsym, tsym->st_shndx); 2418 continue; 2419 } 2420 } 2421 } 2422 2423 /* 2424 * Associate weak (alias) symbols to their non-weak counterparts by 2425 * scaning the global symbols one more time. 2426 * 2427 * This association is needed when processing the symbols from a shared 2428 * object dependency when a a weak definition satisfies a reference: 2429 * 2430 * - When building a dynamic executable, if a referenced symbol is a 2431 * data item, the symbol data is copied to the executables address 2432 * space. In this copy-relocation case, we must also reassociate 2433 * the alias symbol with its new location in the executable. 2434 * 2435 * - If the referenced symbol is a function then we may need to 2436 * promote the symbols binding from undefined weak to undefined, 2437 * otherwise the run-time linker will not generate the correct 2438 * relocation error should the symbol not be found. 2439 * 2440 * Weak alias association is also required when a local dynsym table 2441 * is being created. This table should only contain one instance of a 2442 * symbol that is associated to a given address. 2443 * 2444 * The true association between a weak/strong symbol pair is that both 2445 * symbol entries are identical, thus first we create a sorted symbol 2446 * list keyed off of the symbols section index and value. If the symbol 2447 * belongs to the same section and has the same value, then the chances 2448 * are that the rest of the symbols data is the same. This list is then 2449 * scanned for weak symbols, and if one is found then any strong 2450 * association will exist in the entries that follow. Thus we just have 2451 * to scan one (typically a single alias) or more (in the uncommon 2452 * instance of multiple weak to strong associations) entries to 2453 * determine if a match exists. 2454 */ 2455 if (weak && (OFL_ALLOW_LDYNSYM(ofl) || (etype == ET_DYN)) && 2456 (total > local)) { 2457 static Sym_desc **sort; 2458 static size_t osize = 0; 2459 size_t nsize = (total - local) * sizeof (Sym_desc *); 2460 2461 /* 2462 * As we might be processing many input files, and many symbols, 2463 * try and reuse a static sort buffer. Note, presently we're 2464 * playing the game of never freeing any buffers as there's a 2465 * belief this wastes time. 2466 */ 2467 if ((osize == 0) || (nsize > osize)) { 2468 if ((sort = libld_malloc(nsize)) == NULL) 2469 return (S_ERROR); 2470 osize = nsize; 2471 } 2472 (void) memcpy((void *)sort, &ifl->ifl_oldndx[local], nsize); 2473 2474 qsort(sort, (total - local), sizeof (Sym_desc *), compare); 2475 2476 for (ndx = 0; ndx < (total - local); ndx++) { 2477 Sym_desc *wsdp = sort[ndx]; 2478 Sym *wsym; 2479 int sndx; 2480 2481 /* 2482 * Ignore any empty symbol descriptor, or the case where 2483 * the symbol has been resolved to a different file. 2484 */ 2485 if ((wsdp == NULL) || (wsdp->sd_file != ifl)) 2486 continue; 2487 2488 wsym = wsdp->sd_sym; 2489 2490 if ((wsym->st_shndx == SHN_UNDEF) || 2491 (wsdp->sd_flags & FLG_SY_SPECSEC) || 2492 (ELF_ST_BIND(wsym->st_info) != STB_WEAK)) 2493 continue; 2494 2495 /* 2496 * We have a weak symbol, if it has a strong alias it 2497 * will have been sorted to one of the following sort 2498 * table entries. Note that we could have multiple weak 2499 * symbols aliased to one strong (if this occurs then 2500 * the strong symbol only maintains one alias back to 2501 * the last weak). 2502 */ 2503 for (sndx = ndx + 1; sndx < (total - local); sndx++) { 2504 Sym_desc *ssdp = sort[sndx]; 2505 Sym *ssym; 2506 int w_dynbits, s_dynbits; 2507 2508 /* 2509 * Ignore any empty symbol descriptor, or the 2510 * case where the symbol has been resolved to a 2511 * different file. 2512 */ 2513 if ((ssdp == NULL) || (ssdp->sd_file != ifl)) 2514 continue; 2515 2516 ssym = ssdp->sd_sym; 2517 2518 if (ssym->st_shndx == SHN_UNDEF) 2519 continue; 2520 2521 if ((ssym->st_shndx != wsym->st_shndx) || 2522 (ssym->st_value != wsym->st_value)) 2523 break; 2524 2525 if ((ssym->st_size != wsym->st_size) || 2526 (ssdp->sd_flags & FLG_SY_SPECSEC) || 2527 (ELF_ST_BIND(ssym->st_info) == STB_WEAK)) 2528 continue; 2529 2530 /* 2531 * If a sharable object, set link fields so 2532 * that they reference each other.` 2533 */ 2534 if (etype == ET_DYN) { 2535 ssdp->sd_aux->sa_linkndx = 2536 (Word)wsdp->sd_symndx; 2537 wsdp->sd_aux->sa_linkndx = 2538 (Word)ssdp->sd_symndx; 2539 } 2540 2541 /* 2542 * Determine which of these two symbols go into 2543 * the sort section. If a mapfile has made 2544 * explicit settings of the FLG_SY_*DYNSORT 2545 * flags for both symbols, then we do what they 2546 * say. If one has the DYNSORT flags set, we 2547 * set the NODYNSORT bit in the other. And if 2548 * neither has an explicit setting, then we 2549 * favor the weak symbol because they usually 2550 * lack the leading underscore. 2551 */ 2552 w_dynbits = wsdp->sd_flags & 2553 (FLG_SY_DYNSORT | FLG_SY_NODYNSORT); 2554 s_dynbits = ssdp->sd_flags & 2555 (FLG_SY_DYNSORT | FLG_SY_NODYNSORT); 2556 if (!(w_dynbits && s_dynbits)) { 2557 if (s_dynbits) { 2558 if (s_dynbits == FLG_SY_DYNSORT) 2559 wsdp->sd_flags |= 2560 FLG_SY_NODYNSORT; 2561 } else if (w_dynbits != 2562 FLG_SY_NODYNSORT) { 2563 ssdp->sd_flags |= 2564 FLG_SY_NODYNSORT; 2565 } 2566 } 2567 break; 2568 } 2569 } 2570 } 2571 return (1); 2572 2573 #undef SYM_LOC_BADADDR 2574 } 2575 2576 /* 2577 * Add an undefined symbol to the symbol table. The reference originates from 2578 * the location identifed by the message id (mid). These references can 2579 * originate from command line options such as -e, -u, -initarray, etc. 2580 * (identified with MSG_INTL(MSG_STR_COMMAND)), or from internally generated 2581 * TLS relocation references (identified with MSG_INTL(MSG_STR_TLSREL)). 2582 */ 2583 Sym_desc * 2584 ld_sym_add_u(const char *name, Ofl_desc *ofl, Msg mid) 2585 { 2586 Sym *sym; 2587 Ifl_desc *ifl = NULL, *_ifl; 2588 Sym_desc *sdp; 2589 Word hash; 2590 Aliste idx; 2591 avl_index_t where; 2592 const char *reference = MSG_INTL(mid); 2593 2594 /* 2595 * As an optimization, determine whether we've already generated this 2596 * reference. If the symbol doesn't already exist we'll create it. 2597 * Or if the symbol does exist from a different source, we'll resolve 2598 * the conflict. 2599 */ 2600 /* LINTED */ 2601 hash = (Word)elf_hash(name); 2602 if ((sdp = ld_sym_find(name, hash, &where, ofl)) != NULL) { 2603 if ((sdp->sd_sym->st_shndx == SHN_UNDEF) && 2604 (sdp->sd_file->ifl_name == reference)) 2605 return (sdp); 2606 } 2607 2608 /* 2609 * Determine whether a pseudo input file descriptor exists to represent 2610 * the command line, as any global symbol needs an input file descriptor 2611 * during any symbol resolution (refer to map_ifl() which provides a 2612 * similar method for adding symbols from mapfiles). 2613 */ 2614 for (APLIST_TRAVERSE(ofl->ofl_objs, idx, _ifl)) 2615 if (strcmp(_ifl->ifl_name, reference) == 0) { 2616 ifl = _ifl; 2617 break; 2618 } 2619 2620 /* 2621 * If no descriptor exists create one. 2622 */ 2623 if (ifl == NULL) { 2624 if ((ifl = libld_calloc(sizeof (Ifl_desc), 1)) == NULL) 2625 return ((Sym_desc *)S_ERROR); 2626 ifl->ifl_name = reference; 2627 ifl->ifl_flags = FLG_IF_NEEDED | FLG_IF_FILEREF; 2628 if ((ifl->ifl_ehdr = libld_calloc(sizeof (Ehdr), 1)) == NULL) 2629 return ((Sym_desc *)S_ERROR); 2630 ifl->ifl_ehdr->e_type = ET_REL; 2631 2632 if (aplist_append(&ofl->ofl_objs, ifl, AL_CNT_OFL_OBJS) == NULL) 2633 return ((Sym_desc *)S_ERROR); 2634 } 2635 2636 /* 2637 * Allocate a symbol structure and add it to the global symbol table. 2638 */ 2639 if ((sym = libld_calloc(sizeof (Sym), 1)) == NULL) 2640 return ((Sym_desc *)S_ERROR); 2641 sym->st_info = ELF_ST_INFO(STB_GLOBAL, STT_NOTYPE); 2642 sym->st_shndx = SHN_UNDEF; 2643 2644 DBG_CALL(Dbg_syms_process(ofl->ofl_lml, ifl)); 2645 if (sdp == NULL) { 2646 DBG_CALL(Dbg_syms_global(ofl->ofl_lml, 0, name)); 2647 if ((sdp = ld_sym_enter(name, sym, hash, ifl, ofl, 0, SHN_UNDEF, 2648 0, 0, &where)) == (Sym_desc *)S_ERROR) 2649 return ((Sym_desc *)S_ERROR); 2650 } else if (ld_sym_resolve(sdp, sym, ifl, ofl, 0, 2651 SHN_UNDEF, 0) == S_ERROR) 2652 return ((Sym_desc *)S_ERROR); 2653 2654 sdp->sd_flags &= ~FLG_SY_CLEAN; 2655 sdp->sd_flags |= FLG_SY_CMDREF; 2656 2657 return (sdp); 2658 } 2659