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 2008 Sun Microsystems, Inc. All rights reserved. 28 * Use is subject to license terms. 29 */ 30 #pragma ident "%Z%%M% %I% %E% SMI" 31 32 /* 33 * Symbol table management routines 34 */ 35 36 #define ELF_TARGET_AMD64 37 38 #include <stdio.h> 39 #include <string.h> 40 #include <debug.h> 41 #include "msg.h" 42 #include "_libld.h" 43 44 /* 45 * AVL tree comparator function: 46 * 47 * The primary key is the 'sa_hashval' with a secondary 48 * key of the symbol name itself. 49 */ 50 int 51 ld_sym_avl_comp(const void *elem1, const void *elem2) 52 { 53 int res; 54 Sym_avlnode *sav1 = (Sym_avlnode *)elem1; 55 Sym_avlnode *sav2 = (Sym_avlnode *)elem2; 56 57 res = sav1->sav_hash - sav2->sav_hash; 58 59 if (res < 0) 60 return (-1); 61 if (res > 0) 62 return (1); 63 64 /* 65 * Hash is equal - now compare name 66 */ 67 res = strcmp(sav1->sav_name, sav2->sav_name); 68 if (res == 0) 69 return (0); 70 if (res > 0) 71 return (1); 72 return (-1); 73 } 74 75 76 /* 77 * Focal point for verifying symbol names. 78 */ 79 inline static const char * 80 string(Ofl_desc *ofl, Ifl_desc *ifl, Sym *sym, const char *strs, size_t strsize, 81 int symndx, Word shndx, const char *symsecname, const char *strsecname, 82 Word *flags) 83 { 84 Word name = sym->st_name; 85 86 if (name) { 87 if ((ifl->ifl_flags & FLG_IF_HSTRTAB) == 0) { 88 eprintf(ofl->ofl_lml, ERR_FATAL, 89 MSG_INTL(MSG_FIL_NOSTRTABLE), ifl->ifl_name, 90 symsecname, symndx, EC_XWORD(name)); 91 return (0); 92 } 93 if (name >= (Word)strsize) { 94 eprintf(ofl->ofl_lml, ERR_FATAL, 95 MSG_INTL(MSG_FIL_EXCSTRTABLE), ifl->ifl_name, 96 symsecname, symndx, EC_XWORD(name), 97 strsecname, EC_XWORD(strsize)); 98 return (0); 99 } 100 } 101 102 /* 103 * Determine if we're dealing with a register and if so validate it. 104 * If it's a scratch register, a fabricated name will be returned. 105 */ 106 if (ld_targ.t_ms.ms_is_regsym != NULL) { 107 const char *regname = (*ld_targ.t_ms.ms_is_regsym)(ofl, ifl, 108 sym, strs, symndx, shndx, symsecname, flags); 109 110 if (regname == (const char *)S_ERROR) { 111 return (0); 112 } 113 if (regname) 114 return (regname); 115 } 116 117 /* 118 * If this isn't a register, but we have a global symbol with a null 119 * name, we're not going to be able to hash this, search for it, or 120 * do anything interesting. However, we've been accepting a symbol of 121 * this kind for ages now, so give the user a warning (rather than a 122 * fatal error), just in case this instance exists somewhere in the 123 * world and hasn't, as yet, been a problem. 124 */ 125 if ((name == 0) && (ELF_ST_BIND(sym->st_info) != STB_LOCAL)) { 126 eprintf(ofl->ofl_lml, ERR_WARNING, MSG_INTL(MSG_FIL_NONAMESYM), 127 ifl->ifl_name, symsecname, symndx, EC_XWORD(name)); 128 } 129 return (strs + name); 130 } 131 132 133 /* 134 * For producing symbol names strings to use in error messages. 135 * If the symbol has a non-null name, then the string returned by 136 * this function is the output from demangle(), surrounded by 137 * single quotes. For null names, a descriptive string giving 138 * the symbol section and index is generated. 139 * 140 * This function uses an internal static buffer to hold the resulting 141 * string. The value returned is usable by the caller until the next 142 * call, at which point it is overwritten. 143 */ 144 static const char * 145 demangle_symname(const char *name, const char *symtab_name, Word symndx) 146 { 147 #define INIT_BUFSIZE 256 148 149 static char *buf; 150 static size_t bufsize = 0; 151 152 size_t len; 153 int use_name; 154 155 156 use_name = (name != NULL) && (*name != '\0'); 157 158 if (use_name) { 159 name = demangle(name); 160 len = strlen(name) + 2; /* Include room for quotes */ 161 } else { 162 name = MSG_ORIG(MSG_STR_EMPTY); 163 len = strlen(symtab_name) + 2 + CONV32_INV_BUFSIZE; 164 } 165 len++; /* Null termination */ 166 167 /* If our buffer is too small, double it until it is big enough */ 168 if (len > bufsize) { 169 size_t new_bufsize = bufsize; 170 char *new_buf; 171 172 if (new_bufsize == 0) 173 new_bufsize = INIT_BUFSIZE; 174 while (len > new_bufsize) 175 new_bufsize *= 2; 176 new_buf = libld_malloc(new_bufsize); 177 if (new_buf == NULL) 178 return (name); 179 buf = new_buf; 180 bufsize = new_bufsize; 181 } 182 183 if (use_name) { 184 (void) snprintf(buf, bufsize, MSG_ORIG(MSG_FMT_SYMNAM), name); 185 } else { 186 (void) snprintf(buf, bufsize, MSG_ORIG(MSG_FMT_NULLSYMNAM), 187 symtab_name, EC_WORD(symndx)); 188 } 189 190 return (buf); 191 192 #undef INIT_BUFSIZE 193 } 194 195 /* 196 * Shared objects can be built that define specific symbols that can not be 197 * directly bound to. These objects have a syminfo section (and an associated 198 * DF_1_NODIRECT dynamic flags entry). Scan this table looking for symbols 199 * that can't be bound to directly, and if this files symbol is presently 200 * referenced, mark it so that we don't directly bind to it. 201 */ 202 uintptr_t 203 ld_sym_nodirect(Is_desc *isp, Ifl_desc *ifl, Ofl_desc *ofl) 204 { 205 Shdr *sifshdr, *symshdr; 206 Syminfo *sifdata; 207 Sym *symdata; 208 char *strdata; 209 ulong_t cnt, _cnt; 210 211 /* 212 * Get the syminfo data, and determine the number of entries. 213 */ 214 sifshdr = isp->is_shdr; 215 sifdata = (Syminfo *)isp->is_indata->d_buf; 216 cnt = sifshdr->sh_size / sifshdr->sh_entsize; 217 218 /* 219 * Get the associated symbol table. 220 */ 221 symshdr = ifl->ifl_isdesc[sifshdr->sh_link]->is_shdr; 222 symdata = ifl->ifl_isdesc[sifshdr->sh_link]->is_indata->d_buf; 223 224 /* 225 * Get the string table associated with the symbol table. 226 */ 227 strdata = ifl->ifl_isdesc[symshdr->sh_link]->is_indata->d_buf; 228 229 /* 230 * Traverse the syminfo data for symbols that can't be directly 231 * bound to. 232 */ 233 for (_cnt = 1, sifdata++; _cnt < cnt; _cnt++, sifdata++) { 234 Sym *sym; 235 char *str; 236 Sym_desc *sdp; 237 238 if ((sifdata->si_flags & SYMINFO_FLG_NOEXTDIRECT) == 0) 239 continue; 240 241 sym = (Sym *)(symdata + _cnt); 242 str = (char *)(strdata + sym->st_name); 243 244 if (sdp = ld_sym_find(str, SYM_NOHASH, 0, ofl)) { 245 if (ifl != sdp->sd_file) 246 continue; 247 248 sdp->sd_flags1 &= ~FLG_SY1_DIR; 249 sdp->sd_flags1 |= FLG_SY1_NDIR; 250 } 251 } 252 return (0); 253 } 254 255 /* 256 * If, during symbol processing, it is necessary to update a local symbols 257 * contents before we have generated the symbol tables in the output image, 258 * create a new symbol structure and copy the original symbol contents. While 259 * we are processing the input files, their local symbols are part of the 260 * read-only mapped image. Commonly, these symbols are copied to the new output 261 * file image and then updated to reflect their new address and any change in 262 * attributes. However, sometimes during relocation counting, it is necessary 263 * to adjust the symbols information. This routine provides for the generation 264 * of a new symbol image so that this update can be performed. 265 * All global symbols are copied to an internal symbol table to improve locality 266 * of reference and hence performance, and thus this copying is not necessary. 267 */ 268 uintptr_t 269 ld_sym_copy(Sym_desc *sdp) 270 { 271 Sym *nsym; 272 273 if (sdp->sd_flags & FLG_SY_CLEAN) { 274 if ((nsym = libld_malloc(sizeof (Sym))) == 0) 275 return (S_ERROR); 276 *nsym = *(sdp->sd_sym); 277 sdp->sd_sym = nsym; 278 sdp->sd_flags &= ~FLG_SY_CLEAN; 279 } 280 return (1); 281 } 282 283 /* 284 * Finds a given name in the link editors internal symbol table. If no 285 * hash value is specified it is calculated. A pointer to the located 286 * Sym_desc entry is returned, or NULL if the symbol is not found. 287 */ 288 Sym_desc * 289 ld_sym_find(const char *name, Word hash, avl_index_t *where, Ofl_desc *ofl) 290 { 291 Sym_avlnode qsav; 292 Sym_avlnode *sav; 293 294 if (hash == SYM_NOHASH) 295 /* LINTED */ 296 hash = (Word)elf_hash((const char *)name); 297 qsav.sav_hash = hash; 298 qsav.sav_name = name; 299 300 /* 301 * Perform search for symbol in AVL tree. Note that the 'where' field 302 * is passed in from the caller. If a 'where' is present, it can be 303 * used in subsequent 'ld_sym_enter()' calls if required. 304 */ 305 sav = avl_find(&ofl->ofl_symavl, &qsav, where); 306 307 /* 308 * If symbol was not found in the avl tree, return null to show that. 309 */ 310 if (sav == 0) 311 return (0); 312 313 /* 314 * Return symbol found. 315 */ 316 return (sav->sav_symdesc); 317 } 318 319 320 /* 321 * Enter a new symbol into the link editors internal symbol table. 322 * If the symbol is from an input file, information regarding the input file 323 * and input section is also recorded. Otherwise (file == NULL) the symbol 324 * has been internally generated (ie. _etext, _edata, etc.). 325 */ 326 Sym_desc * 327 ld_sym_enter(const char *name, Sym *osym, Word hash, Ifl_desc *ifl, 328 Ofl_desc *ofl, Word ndx, Word shndx, Word sdflags, Half sdflags1, 329 avl_index_t *where) 330 { 331 Sym_desc *sdp; 332 Sym_aux *sap; 333 Sym_avlnode *savl; 334 char *_name; 335 Sym *nsym; 336 Half etype; 337 uchar_t vis; 338 avl_index_t _where; 339 340 /* 341 * Establish the file type. 342 */ 343 if (ifl) 344 etype = ifl->ifl_ehdr->e_type; 345 else 346 etype = ET_NONE; 347 348 ofl->ofl_entercnt++; 349 350 /* 351 * Allocate a Sym Descriptor, Auxiliary Descriptor, and a Sym AVLNode - 352 * contiguously. 353 */ 354 if ((savl = libld_calloc(sizeof (Sym_avlnode) + sizeof (Sym_desc) + 355 sizeof (Sym_aux), 1)) == 0) 356 return ((Sym_desc *)S_ERROR); 357 sdp = (Sym_desc *)((uintptr_t)savl + sizeof (Sym_avlnode)); 358 sap = (Sym_aux *)((uintptr_t)sdp + sizeof (Sym_desc)); 359 360 savl->sav_symdesc = sdp; 361 sdp->sd_file = ifl; 362 sdp->sd_aux = sap; 363 savl->sav_hash = sap->sa_hash = hash; 364 365 /* 366 * Copy the symbol table entry from the input file into the internal 367 * entry and have the symbol descriptor use it. 368 */ 369 sdp->sd_sym = nsym = &sap->sa_sym; 370 *nsym = *osym; 371 sdp->sd_shndx = shndx; 372 sdp->sd_flags |= sdflags; 373 sdp->sd_flags1 |= sdflags1; 374 375 if ((_name = libld_malloc(strlen(name) + 1)) == 0) 376 return ((Sym_desc *)S_ERROR); 377 savl->sav_name = sdp->sd_name = (const char *)strcpy(_name, name); 378 379 /* 380 * Enter Symbol in AVL tree. 381 */ 382 if (where == 0) { 383 /* LINTED */ 384 Sym_avlnode *_savl; 385 /* 386 * If a previous ld_sym_find() hasn't initialized 'where' do it 387 * now. 388 */ 389 where = &_where; 390 _savl = avl_find(&ofl->ofl_symavl, savl, where); 391 assert(_savl == 0); 392 } 393 avl_insert(&ofl->ofl_symavl, savl, *where); 394 395 /* 396 * Record the section index. This is possible because the 397 * `ifl_isdesc' table is filled before we start symbol processing. 398 */ 399 if ((sdflags & FLG_SY_SPECSEC) || (nsym->st_shndx == SHN_UNDEF)) 400 sdp->sd_isc = NULL; 401 else { 402 sdp->sd_isc = ifl->ifl_isdesc[shndx]; 403 404 /* 405 * If this symbol is from a relocatable object, make sure that 406 * it is still associated with a section. For example, an 407 * unknown section type (SHT_NULL) would have been rejected on 408 * input with a warning. Here, we make the use of the symbol 409 * fatal. A symbol descriptor is still returned, so that the 410 * caller can continue processing all symbols, and hence flush 411 * out as many error conditions as possible. 412 */ 413 if ((etype == ET_REL) && (sdp->sd_isc == 0)) { 414 eprintf(ofl->ofl_lml, ERR_FATAL, 415 MSG_INTL(MSG_SYM_INVSEC), name, ifl->ifl_name, 416 EC_XWORD(shndx)); 417 ofl->ofl_flags |= FLG_OF_FATAL; 418 return (sdp); 419 } 420 } 421 422 /* 423 * Mark any COMMON symbols as 'tentative'. 424 */ 425 if (sdflags & FLG_SY_SPECSEC) { 426 if (nsym->st_shndx == SHN_COMMON) 427 sdp->sd_flags |= FLG_SY_TENTSYM; 428 #if defined(_ELF64) 429 else if ((ld_targ.t_m.m_mach == EM_AMD64) && 430 (nsym->st_shndx == SHN_X86_64_LCOMMON)) 431 sdp->sd_flags |= FLG_SY_TENTSYM; 432 #endif 433 } 434 435 /* 436 * Establish the symbols visibility and reference. 437 */ 438 vis = ELF_ST_VISIBILITY(nsym->st_other); 439 440 if ((etype == ET_NONE) || (etype == ET_REL)) { 441 switch (vis) { 442 case STV_DEFAULT: 443 sdp->sd_flags1 |= FLG_SY1_DEFAULT; 444 break; 445 case STV_INTERNAL: 446 case STV_HIDDEN: 447 sdp->sd_flags1 |= FLG_SY1_HIDDEN; 448 break; 449 case STV_PROTECTED: 450 sdp->sd_flags1 |= FLG_SY1_PROTECT; 451 break; 452 case STV_EXPORTED: 453 sdp->sd_flags1 |= FLG_SY1_EXPORT; 454 break; 455 case STV_SINGLETON: 456 sdp->sd_flags1 |= (FLG_SY1_SINGLE | FLG_SY1_NDIR); 457 ofl->ofl_flags1 |= FLG_OF1_NDIRECT; 458 break; 459 case STV_ELIMINATE: 460 sdp->sd_flags1 |= (FLG_SY1_HIDDEN | FLG_SY1_ELIM); 461 break; 462 default: 463 assert(vis <= STV_ELIMINATE); 464 } 465 466 sdp->sd_ref = REF_REL_NEED; 467 468 /* 469 * Under -Bnodirect, all exported interfaces that have not 470 * explicitly been defined protected or directly bound to, are 471 * tagged to prevent direct binding. 472 */ 473 if ((ofl->ofl_flags1 & FLG_OF1_ALNODIR) && 474 ((sdp->sd_flags1 & (FLG_SY1_PROTECT | FLG_SY1_DIR)) == 0) && 475 (nsym->st_shndx != SHN_UNDEF)) { 476 sdp->sd_flags1 |= FLG_SY1_NDIR; 477 } 478 } else { 479 sdp->sd_ref = REF_DYN_SEEN; 480 481 /* 482 * Record the binding file for this symbol in the sa_bindto 483 * field. If this symbol is ever overridden by a REF_REL_NEED 484 * definition, sa_bindto is used when building a 'translator'. 485 */ 486 if (nsym->st_shndx != SHN_UNDEF) 487 sdp->sd_aux->sa_bindto = ifl; 488 489 /* 490 * If this is a protected symbol, remember this. Note, this 491 * state is different from the FLG_SY1_PROTECT used to establish 492 * a symbol definitions visibility. This state is used to warn 493 * against possible copy relocations against this referenced 494 * symbol. 495 */ 496 if (vis == STV_PROTECTED) 497 sdp->sd_flags |= FLG_SY_PROT; 498 499 /* 500 * If this is a SINGLETON definition, then indicate the symbol 501 * can not be directly bound to, and retain the visibility. 502 * This visibility will be inherited by any references made to 503 * this symbol. 504 */ 505 if ((vis == STV_SINGLETON) && (nsym->st_shndx != SHN_UNDEF)) 506 sdp->sd_flags1 |= (FLG_SY1_SINGLE | FLG_SY1_NDIR); 507 508 /* 509 * If the new symbol is from a shared library and is associated 510 * with a SHT_NOBITS section then this symbol originated from a 511 * tentative symbol. 512 */ 513 if (sdp->sd_isc && 514 (sdp->sd_isc->is_shdr->sh_type == SHT_NOBITS)) 515 sdp->sd_flags |= FLG_SY_TENTSYM; 516 } 517 518 /* 519 * Reclassify any SHN_SUNW_IGNORE symbols to SHN_UNDEF so as to 520 * simplify future processing. 521 */ 522 if (nsym->st_shndx == SHN_SUNW_IGNORE) { 523 sdp->sd_shndx = shndx = SHN_UNDEF; 524 sdp->sd_flags |= FLG_SY_REDUCED; 525 sdp->sd_flags1 |= 526 (FLG_SY1_HIDDEN | FLG_SY1_IGNORE | FLG_SY1_ELIM); 527 } 528 529 /* 530 * If this is an undefined, or common symbol from a relocatable object 531 * determine whether it is a global or weak reference (see build_osym(), 532 * where REF_DYN_NEED definitions are returned back to undefines). 533 */ 534 if ((etype == ET_REL) && 535 (ELF_ST_BIND(nsym->st_info) == STB_GLOBAL) && 536 ((nsym->st_shndx == SHN_UNDEF) || ((sdflags & FLG_SY_SPECSEC) && 537 #if defined(_ELF64) 538 ((nsym->st_shndx == SHN_COMMON) || 539 ((ld_targ.t_m.m_mach == EM_AMD64) && 540 (nsym->st_shndx == SHN_X86_64_LCOMMON)))))) 541 #else 542 /* BEGIN CSTYLED */ 543 (nsym->st_shndx == SHN_COMMON)))) 544 /* END CSTYLED */ 545 #endif 546 sdp->sd_flags |= FLG_SY_GLOBREF; 547 548 /* 549 * Record the input filename on the referenced or defined files list 550 * for possible later diagnostics. The `sa_rfile' pointer contains the 551 * name of the file that first referenced this symbol and is used to 552 * generate undefined symbol diagnostics (refer to sym_undef_entry()). 553 * Note that this entry can be overridden if a reference from a 554 * relocatable object is found after a reference from a shared object 555 * (refer to sym_override()). 556 * The `sa_dfiles' list is used to maintain the list of files that 557 * define the same symbol. This list can be used for two reasons: 558 * 559 * o To save the first definition of a symbol that is not available 560 * for this link-edit. 561 * 562 * o To save all definitions of a symbol when the -m option is in 563 * effect. This is optional as it is used to list multiple 564 * (interposed) definitions of a symbol (refer to ldmap_out()), 565 * and can be quite expensive. 566 */ 567 if (nsym->st_shndx == SHN_UNDEF) { 568 sap->sa_rfile = ifl->ifl_name; 569 } else { 570 if (sdp->sd_ref == REF_DYN_SEEN) { 571 /* 572 * A symbol is determined to be unavailable if it 573 * belongs to a version of a shared object that this 574 * user does not wish to use, or if it belongs to an 575 * implicit shared object. 576 */ 577 if (ifl->ifl_vercnt) { 578 Ver_index *vip; 579 Half vndx = ifl->ifl_versym[ndx]; 580 581 sap->sa_dverndx = vndx; 582 vip = &ifl->ifl_verndx[vndx]; 583 if (!(vip->vi_flags & FLG_VER_AVAIL)) { 584 sdp->sd_flags |= FLG_SY_NOTAVAIL; 585 sap->sa_vfile = ifl->ifl_name; 586 } 587 } 588 if (!(ifl->ifl_flags & FLG_IF_NEEDED)) 589 sdp->sd_flags |= FLG_SY_NOTAVAIL; 590 591 } else if (etype == ET_REL) { 592 /* 593 * If this symbol has been obtained from a versioned 594 * input relocatable object then the new symbol must be 595 * promoted to the versioning of the output file. 596 */ 597 if (ifl->ifl_versym) 598 ld_vers_promote(sdp, ndx, ifl, ofl); 599 } 600 601 if ((ofl->ofl_flags & FLG_OF_GENMAP) && 602 ((sdflags & FLG_SY_SPECSEC) == 0)) 603 if (list_appendc(&sap->sa_dfiles, ifl->ifl_name) == 0) 604 return ((Sym_desc *)S_ERROR); 605 } 606 607 /* 608 * Provided we're not processing a mapfile, diagnose the entered symbol. 609 * Mapfile processing requires the symbol to be updated with additional 610 * information, therefore the diagnosing of the symbol is deferred until 611 * later (see Dbg_map_symbol()). 612 */ 613 if ((ifl == 0) || ((ifl->ifl_flags & FLG_IF_MAPFILE) == 0)) 614 DBG_CALL(Dbg_syms_entered(ofl, nsym, sdp)); 615 return (sdp); 616 } 617 618 /* 619 * Add a special symbol to the symbol table. Takes special symbol name with 620 * and without underscores. This routine is called, after all other symbol 621 * resolution has completed, to generate a reserved absolute symbol (the 622 * underscore version). Special symbols are updated with the appropriate 623 * values in update_osym(). If the user has already defined this symbol 624 * issue a warning and leave the symbol as is. If the non-underscore symbol 625 * is referenced then turn it into a weak alias of the underscored symbol. 626 * 627 * The bits in flags_u are OR'd into the flags field of the symbol 628 * for the underscored symbol. 629 * 630 * If this is a global symbol, and it hasn't explicitly been defined as being 631 * directly bound to, indicate that it can't be directly bound to. 632 * Historically, most special symbols only have meaning to the object in which 633 * they exist, however, they've always been global. To ensure compatibility 634 * with any unexpected use presently in effect, ensure these symbols don't get 635 * directly bound to. Note, that establishing this state here isn't sufficient 636 * to create a syminfo table, only if a syminfo table is being created by some 637 * other symbol directives will the nodirect binding be recorded. This ensures 638 * we don't create syminfo sections for all objects we create, as this might add 639 * unnecessary bloat to users who haven't explicitly requested extra symbol 640 * information. 641 */ 642 static uintptr_t 643 sym_add_spec(const char *name, const char *uname, Word sdaux_id, 644 Word flags_u, Half flags1, Ofl_desc *ofl) 645 { 646 Sym_desc *sdp; 647 Sym_desc *usdp; 648 Sym *sym; 649 Word hash; 650 avl_index_t where; 651 652 /* LINTED */ 653 hash = (Word)elf_hash(uname); 654 if (usdp = ld_sym_find(uname, hash, &where, ofl)) { 655 /* 656 * If the underscore symbol exists and is undefined, or was 657 * defined in a shared library, convert it to a local symbol. 658 * Otherwise leave it as is and warn the user. 659 */ 660 if ((usdp->sd_shndx == SHN_UNDEF) || 661 (usdp->sd_ref != REF_REL_NEED)) { 662 usdp->sd_ref = REF_REL_NEED; 663 usdp->sd_shndx = usdp->sd_sym->st_shndx = SHN_ABS; 664 usdp->sd_flags |= FLG_SY_SPECSEC | flags_u; 665 usdp->sd_sym->st_info = 666 ELF_ST_INFO(STB_GLOBAL, STT_OBJECT); 667 usdp->sd_isc = NULL; 668 usdp->sd_sym->st_size = 0; 669 usdp->sd_sym->st_value = 0; 670 /* LINTED */ 671 usdp->sd_aux->sa_symspec = (Half)sdaux_id; 672 673 /* 674 * If a user hasn't specifically indicated that the 675 * scope of this symbol be made local, then leave it 676 * as global (ie. prevent automatic scoping). The GOT 677 * should be defined protected, whereas all other 678 * special symbols are tagged as no-direct. 679 */ 680 if (((usdp->sd_flags1 & FLG_SY1_HIDDEN) == 0) && 681 (flags1 & FLG_SY1_DEFAULT)) { 682 usdp->sd_aux->sa_overndx = VER_NDX_GLOBAL; 683 if (sdaux_id == SDAUX_ID_GOT) { 684 usdp->sd_flags1 &= ~FLG_SY1_NDIR; 685 usdp->sd_flags1 |= FLG_SY1_PROTECT; 686 usdp->sd_sym->st_other = STV_PROTECTED; 687 } else if ( 688 ((usdp->sd_flags1 & FLG_SY1_DIR) == 0) && 689 ((ofl->ofl_flags & FLG_OF_SYMBOLIC) == 0)) { 690 usdp->sd_flags1 |= FLG_SY1_NDIR; 691 } 692 } 693 usdp->sd_flags1 |= flags1; 694 695 /* 696 * If the reference originated from a mapfile ensure 697 * we mark the symbol as used. 698 */ 699 if (usdp->sd_flags & FLG_SY_MAPREF) 700 usdp->sd_flags |= FLG_SY_MAPUSED; 701 702 DBG_CALL(Dbg_syms_updated(ofl, usdp, uname)); 703 } else 704 eprintf(ofl->ofl_lml, ERR_WARNING, 705 MSG_INTL(MSG_SYM_RESERVE), uname, 706 usdp->sd_file->ifl_name); 707 } else { 708 /* 709 * If the symbol does not exist create it. 710 */ 711 if ((sym = libld_calloc(sizeof (Sym), 1)) == 0) 712 return (S_ERROR); 713 sym->st_shndx = SHN_ABS; 714 sym->st_info = ELF_ST_INFO(STB_GLOBAL, STT_OBJECT); 715 sym->st_size = 0; 716 sym->st_value = 0; 717 DBG_CALL(Dbg_syms_created(ofl->ofl_lml, uname)); 718 if ((usdp = ld_sym_enter(uname, sym, hash, (Ifl_desc *)NULL, 719 ofl, 0, SHN_ABS, FLG_SY_SPECSEC | flags_u, 0, &where)) == 720 (Sym_desc *)S_ERROR) 721 return (S_ERROR); 722 usdp->sd_ref = REF_REL_NEED; 723 /* LINTED */ 724 usdp->sd_aux->sa_symspec = (Half)sdaux_id; 725 726 usdp->sd_aux->sa_overndx = VER_NDX_GLOBAL; 727 728 if (sdaux_id == SDAUX_ID_GOT) { 729 usdp->sd_flags1 |= FLG_SY1_PROTECT; 730 usdp->sd_sym->st_other = STV_PROTECTED; 731 } else if ((flags1 & FLG_SY1_DEFAULT) && 732 ((ofl->ofl_flags & FLG_OF_SYMBOLIC) == 0)) { 733 usdp->sd_flags1 |= FLG_SY1_NDIR; 734 } 735 usdp->sd_flags1 |= flags1; 736 } 737 738 if (name && (sdp = ld_sym_find(name, SYM_NOHASH, 0, ofl)) && 739 (sdp->sd_sym->st_shndx == SHN_UNDEF)) { 740 uchar_t bind; 741 742 /* 743 * If the non-underscore symbol exists and is undefined 744 * convert it to be a local. If the underscore has 745 * sa_symspec set (ie. it was created above) then simulate this 746 * as a weak alias. 747 */ 748 sdp->sd_ref = REF_REL_NEED; 749 sdp->sd_shndx = sdp->sd_sym->st_shndx = SHN_ABS; 750 sdp->sd_flags |= FLG_SY_SPECSEC; 751 sdp->sd_isc = NULL; 752 sdp->sd_sym->st_size = 0; 753 sdp->sd_sym->st_value = 0; 754 /* LINTED */ 755 sdp->sd_aux->sa_symspec = (Half)sdaux_id; 756 if (usdp->sd_aux->sa_symspec) { 757 usdp->sd_aux->sa_linkndx = 0; 758 sdp->sd_aux->sa_linkndx = 0; 759 bind = STB_WEAK; 760 } else 761 bind = STB_GLOBAL; 762 sdp->sd_sym->st_info = ELF_ST_INFO(bind, STT_OBJECT); 763 764 /* 765 * If a user hasn't specifically indicated the scope of this 766 * symbol be made local then leave it as global (ie. prevent 767 * automatic scoping). The GOT should be defined protected, 768 * whereas all other special symbols are tagged as no-direct. 769 */ 770 if (((sdp->sd_flags1 & FLG_SY1_HIDDEN) == 0) && 771 (flags1 & FLG_SY1_DEFAULT)) { 772 sdp->sd_aux->sa_overndx = VER_NDX_GLOBAL; 773 if (sdaux_id == SDAUX_ID_GOT) { 774 sdp->sd_flags1 &= ~FLG_SY1_NDIR; 775 sdp->sd_flags1 |= FLG_SY1_PROTECT; 776 sdp->sd_sym->st_other = STV_PROTECTED; 777 } else if (((sdp->sd_flags1 & FLG_SY1_DIR) == 0) && 778 ((ofl->ofl_flags & FLG_OF_SYMBOLIC) == 0)) { 779 sdp->sd_flags1 |= FLG_SY1_NDIR; 780 } 781 } 782 sdp->sd_flags1 |= flags1; 783 784 /* 785 * If the reference originated from a mapfile ensure 786 * we mark the symbol as used. 787 */ 788 if (sdp->sd_flags & FLG_SY_MAPREF) 789 sdp->sd_flags |= FLG_SY_MAPUSED; 790 791 DBG_CALL(Dbg_syms_updated(ofl, sdp, name)); 792 } 793 return (1); 794 } 795 796 797 /* 798 * Print undefined symbols. 799 */ 800 static Boolean undef_title = TRUE; 801 802 static void 803 sym_undef_title(Ofl_desc *ofl) 804 { 805 eprintf(ofl->ofl_lml, ERR_NONE, MSG_INTL(MSG_SYM_FMT_UNDEF), 806 MSG_INTL(MSG_SYM_UNDEF_ITM_11), 807 MSG_INTL(MSG_SYM_UNDEF_ITM_21), 808 MSG_INTL(MSG_SYM_UNDEF_ITM_12), 809 MSG_INTL(MSG_SYM_UNDEF_ITM_22)); 810 811 undef_title = FALSE; 812 } 813 814 /* 815 * Undefined symbols can fall into one of four types: 816 * 817 * o the symbol is really undefined (SHN_UNDEF). 818 * 819 * o versioning has been enabled, however this symbol has not been assigned 820 * to one of the defined versions. 821 * 822 * o the symbol has been defined by an implicitly supplied library, ie. one 823 * which was encounted because it was NEEDED by another library, rather 824 * than from a command line supplied library which would become the only 825 * dependency of the output file being produced. 826 * 827 * o the symbol has been defined by a version of a shared object that is 828 * not permitted for this link-edit. 829 * 830 * In all cases the file who made the first reference to this symbol will have 831 * been recorded via the `sa_rfile' pointer. 832 */ 833 typedef enum { 834 UNDEF, NOVERSION, IMPLICIT, NOTAVAIL, 835 BNDLOCAL 836 } Type; 837 838 static const Msg format[] = { 839 MSG_SYM_UND_UNDEF, /* MSG_INTL(MSG_SYM_UND_UNDEF) */ 840 MSG_SYM_UND_NOVER, /* MSG_INTL(MSG_SYM_UND_NOVER) */ 841 MSG_SYM_UND_IMPL, /* MSG_INTL(MSG_SYM_UND_IMPL) */ 842 MSG_SYM_UND_NOTA, /* MSG_INTL(MSG_SYM_UND_NOTA) */ 843 MSG_SYM_UND_BNDLOCAL /* MSG_INTL(MSG_SYM_UND_BNDLOCAL) */ 844 }; 845 846 static void 847 sym_undef_entry(Ofl_desc *ofl, Sym_desc *sdp, Type type) 848 { 849 const char *name1, *name2, *name3; 850 Ifl_desc *ifl = sdp->sd_file; 851 Sym_aux *sap = sdp->sd_aux; 852 853 if (undef_title) 854 sym_undef_title(ofl); 855 856 switch (type) { 857 case UNDEF: 858 case BNDLOCAL: 859 name1 = sap->sa_rfile; 860 break; 861 case NOVERSION: 862 name1 = ifl->ifl_name; 863 break; 864 case IMPLICIT: 865 name1 = sap->sa_rfile; 866 name2 = ifl->ifl_name; 867 break; 868 case NOTAVAIL: 869 name1 = sap->sa_rfile; 870 name2 = sap->sa_vfile; 871 name3 = ifl->ifl_verndx[sap->sa_dverndx].vi_name; 872 break; 873 default: 874 return; 875 } 876 877 eprintf(ofl->ofl_lml, ERR_NONE, MSG_INTL(format[type]), 878 demangle(sdp->sd_name), name1, name2, name3); 879 } 880 881 /* 882 * At this point all symbol input processing has been completed, therefore 883 * complete the symbol table entries by generating any necessary internal 884 * symbols. 885 */ 886 uintptr_t 887 ld_sym_spec(Ofl_desc *ofl) 888 { 889 Sym_desc *sdp; 890 891 if (ofl->ofl_flags & FLG_OF_RELOBJ) 892 return (1); 893 894 DBG_CALL(Dbg_syms_spec_title(ofl->ofl_lml)); 895 896 if (sym_add_spec(MSG_ORIG(MSG_SYM_ETEXT), MSG_ORIG(MSG_SYM_ETEXT_U), 897 SDAUX_ID_ETEXT, 0, (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), 898 ofl) == S_ERROR) 899 return (S_ERROR); 900 if (sym_add_spec(MSG_ORIG(MSG_SYM_EDATA), MSG_ORIG(MSG_SYM_EDATA_U), 901 SDAUX_ID_EDATA, 0, (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), 902 ofl) == S_ERROR) 903 return (S_ERROR); 904 if (sym_add_spec(MSG_ORIG(MSG_SYM_END), MSG_ORIG(MSG_SYM_END_U), 905 SDAUX_ID_END, FLG_SY_DYNSORT, (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), 906 ofl) == S_ERROR) 907 return (S_ERROR); 908 if (sym_add_spec(MSG_ORIG(MSG_SYM_L_END), MSG_ORIG(MSG_SYM_L_END_U), 909 SDAUX_ID_END, 0, FLG_SY1_HIDDEN, ofl) == S_ERROR) 910 return (S_ERROR); 911 if (sym_add_spec(MSG_ORIG(MSG_SYM_L_START), MSG_ORIG(MSG_SYM_L_START_U), 912 SDAUX_ID_START, 0, FLG_SY1_HIDDEN, ofl) == S_ERROR) 913 return (S_ERROR); 914 915 /* 916 * Historically we've always produced a _DYNAMIC symbol, even for 917 * static executables (in which case its value will be 0). 918 */ 919 if (sym_add_spec(MSG_ORIG(MSG_SYM_DYNAMIC), MSG_ORIG(MSG_SYM_DYNAMIC_U), 920 SDAUX_ID_DYN, FLG_SY_DYNSORT, (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), 921 ofl) == S_ERROR) 922 return (S_ERROR); 923 924 if (OFL_ALLOW_DYNSYM(ofl)) 925 if (sym_add_spec(MSG_ORIG(MSG_SYM_PLKTBL), 926 MSG_ORIG(MSG_SYM_PLKTBL_U), SDAUX_ID_PLT, 927 FLG_SY_DYNSORT, (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), 928 ofl) == S_ERROR) 929 return (S_ERROR); 930 931 /* 932 * A GOT reference will be accompanied by the associated GOT symbol. 933 * Make sure it gets assigned the appropriate special attributes. 934 */ 935 if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_GOFTBL_U), 936 SYM_NOHASH, 0, ofl)) != 0) && (sdp->sd_ref != REF_DYN_SEEN)) { 937 if (sym_add_spec(MSG_ORIG(MSG_SYM_GOFTBL), 938 MSG_ORIG(MSG_SYM_GOFTBL_U), SDAUX_ID_GOT, FLG_SY_DYNSORT, 939 (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), ofl) == S_ERROR) 940 return (S_ERROR); 941 } 942 943 return (1); 944 } 945 946 /* 947 * This routine checks to see if a symbols visibility needs to be reduced to 948 * either SYMBOLIC or LOCAL. This routine can be called from either 949 * reloc_init() or sym_validate(). 950 */ 951 void 952 ld_sym_adjust_vis(Sym_desc *sdp, Ofl_desc *ofl) 953 { 954 ofl_flag_t oflags = ofl->ofl_flags; 955 Sym *sym = sdp->sd_sym; 956 957 if ((sdp->sd_ref == REF_REL_NEED) && 958 (sdp->sd_sym->st_shndx != SHN_UNDEF)) { 959 /* 960 * If auto-reduction/elimination is enabled, reduce any 961 * non-versioned global symbols. This routine is called either 962 * from any initial relocation processing that references this 963 * symbol, or from the symbol validation processing. 964 * 965 * A symbol is a candidate for auto-reduction/elimination if: 966 * 967 * . the symbol wasn't explicitly defined within a mapfile 968 * (in which case all the necessary state has been applied 969 * to the symbol), or 970 * . the symbol isn't one of the family of reserved 971 * special symbols (ie. _end, _etext, etc.), or 972 * . the symbol isn't a SINGLETON, or 973 * . the symbol wasn't explicitly defined within a version 974 * definition associated with an input relocatable object. 975 * 976 * Indicate that the symbol has been reduced as it may be 977 * necessary to print these symbols later. 978 */ 979 if ((oflags & (FLG_OF_AUTOLCL | FLG_OF_AUTOELM)) && 980 ((sdp->sd_flags1 & MSK_SY1_NOAUTO) == 0)) { 981 if ((sdp->sd_flags1 & FLG_SY1_HIDDEN) == 0) { 982 sdp->sd_flags |= FLG_SY_REDUCED; 983 sdp->sd_flags1 |= FLG_SY1_HIDDEN; 984 } 985 986 if (oflags & (FLG_OF_REDLSYM | FLG_OF_AUTOELM)) { 987 sdp->sd_flags1 |= FLG_SY1_ELIM; 988 sym->st_other = STV_ELIMINATE | 989 (sym->st_other & ~MSK_SYM_VISIBILITY); 990 } else if (ELF_ST_VISIBILITY(sym->st_other) != 991 STV_INTERNAL) 992 sym->st_other = STV_HIDDEN | 993 (sym->st_other & ~MSK_SYM_VISIBILITY); 994 } 995 996 /* 997 * If -Bsymbolic is in effect, and the symbol hasn't explicitly 998 * been defined nodirect (via a mapfile), then bind the global 999 * symbol symbolically and assign the STV_PROTECTED visibility 1000 * attribute. 1001 */ 1002 if ((oflags & FLG_OF_SYMBOLIC) && 1003 ((sdp->sd_flags1 & (FLG_SY1_HIDDEN | FLG_SY1_NDIR)) == 0)) { 1004 sdp->sd_flags1 |= FLG_SY1_PROTECT; 1005 if (ELF_ST_VISIBILITY(sym->st_other) == STV_DEFAULT) 1006 sym->st_other = STV_PROTECTED | 1007 (sym->st_other & ~MSK_SYM_VISIBILITY); 1008 } 1009 } 1010 1011 /* 1012 * Indicate that this symbol has had it's visibility checked so that 1013 * we don't need to do this investigation again. 1014 */ 1015 sdp->sd_flags |= FLG_SY_VISIBLE; 1016 } 1017 1018 /* 1019 * Make sure a symbol definition is local to the object being built. 1020 */ 1021 static int 1022 ensure_sym_local(Ofl_desc *ofl, Sym_desc *sdp, const char *str) 1023 { 1024 if (sdp->sd_sym->st_shndx == SHN_UNDEF) { 1025 if (str) { 1026 eprintf(ofl->ofl_lml, ERR_FATAL, 1027 MSG_INTL(MSG_SYM_UNDEF), str, 1028 demangle((char *)sdp->sd_name)); 1029 } 1030 return (1); 1031 } 1032 if (sdp->sd_ref != REF_REL_NEED) { 1033 if (str) { 1034 eprintf(ofl->ofl_lml, ERR_FATAL, 1035 MSG_INTL(MSG_SYM_EXTERN), str, 1036 demangle((char *)sdp->sd_name), 1037 sdp->sd_file->ifl_name); 1038 } 1039 return (1); 1040 } 1041 1042 sdp->sd_flags |= FLG_SY_UPREQD; 1043 if (sdp->sd_isc) { 1044 sdp->sd_isc->is_flags |= FLG_IS_SECTREF; 1045 sdp->sd_isc->is_file->ifl_flags |= FLG_IF_FILEREF; 1046 } 1047 return (0); 1048 } 1049 1050 /* 1051 * Make sure all the symbol definitions required for initarray, finiarray, or 1052 * preinitarray's are local to the object being built. 1053 */ 1054 static int 1055 ensure_array_local(Ofl_desc *ofl, List *list, const char *str) 1056 { 1057 Listnode *lnp; 1058 Sym_desc *sdp; 1059 int ret = 0; 1060 1061 for (LIST_TRAVERSE(list, lnp, sdp)) 1062 ret += ensure_sym_local(ofl, sdp, str); 1063 1064 return (ret); 1065 } 1066 1067 /* 1068 * After all symbol table input processing has been finished, and all relocation 1069 * counting has been carried out (ie. no more symbols will be read, generated, 1070 * or modified), validate and count the relevant entries: 1071 * 1072 * o check and print any undefined symbols remaining. Note that 1073 * if a symbol has been defined by virtue of the inclusion of 1074 * an implicit shared library, it is still classed as undefined. 1075 * 1076 * o count the number of global needed symbols together with the 1077 * size of their associated name strings (if scoping has been 1078 * indicated these symbols may be reduced to locals). 1079 * 1080 * o establish the size and alignment requirements for the global 1081 * .bss section (the alignment of this section is based on the 1082 * first symbol that it will contain). 1083 */ 1084 uintptr_t 1085 ld_sym_validate(Ofl_desc *ofl) 1086 { 1087 Sym_avlnode *sav; 1088 Sym_desc *sdp; 1089 Sym *sym; 1090 ofl_flag_t oflags = ofl->ofl_flags; 1091 ofl_flag_t undef = 0, needed = 0, verdesc = 0; 1092 Xword bssalign = 0, tlsalign = 0; 1093 Xword bsssize = 0, tlssize = 0; 1094 #if defined(_ELF64) 1095 Xword lbssalign = 0, lbsssize = 0; 1096 #endif 1097 int ret; 1098 int allow_ldynsym; 1099 uchar_t type; 1100 1101 /* 1102 * If a symbol is undefined and this link-edit calls for no undefined 1103 * symbols to remain (this is the default case when generating an 1104 * executable but can be enforced for any object using -z defs), the 1105 * symbol is classified as undefined and a fatal error condition will 1106 * be indicated. 1107 * 1108 * If the symbol is undefined and we're creating a shared object with 1109 * the -Bsymbolic flag, then the symbol is also classified as undefined 1110 * and a warning condition will be indicated. 1111 */ 1112 if ((oflags & (FLG_OF_SHAROBJ | FLG_OF_SYMBOLIC)) == 1113 (FLG_OF_SHAROBJ | FLG_OF_SYMBOLIC)) 1114 undef = FLG_OF_WARN; 1115 if (oflags & FLG_OF_NOUNDEF) 1116 undef = FLG_OF_FATAL; 1117 1118 /* 1119 * If the symbol is referenced from an implicitly included shared object 1120 * (ie. it's not on the NEEDED list) then the symbol is also classified 1121 * as undefined and a fatal error condition will be indicated. 1122 */ 1123 if ((oflags & FLG_OF_NOUNDEF) || !(oflags & FLG_OF_SHAROBJ)) 1124 needed = FLG_OF_FATAL; 1125 1126 /* 1127 * If the output image is being versioned all symbol definitions must be 1128 * associated with a version. Any symbol that isn't is classified as 1129 * undefined and a fatal error condition will be indicated. 1130 */ 1131 if ((oflags & FLG_OF_VERDEF) && (ofl->ofl_vercnt > VER_NDX_GLOBAL)) 1132 verdesc = FLG_OF_FATAL; 1133 1134 allow_ldynsym = OFL_ALLOW_LDYNSYM(ofl); 1135 1136 if (allow_ldynsym) { 1137 /* 1138 * Normally, we disallow symbols with 0 size from appearing 1139 * in a dyn[sym|tls]sort section. However, there are some 1140 * symbols that serve special purposes that we want to exempt 1141 * from this rule. Look them up, and set their 1142 * FLG_SY_DYNSORT flag. 1143 */ 1144 static const char *special[] = { 1145 MSG_ORIG(MSG_SYM_INIT_U), /* _init */ 1146 MSG_ORIG(MSG_SYM_FINI_U), /* _fini */ 1147 MSG_ORIG(MSG_SYM_START), /* _start */ 1148 NULL 1149 }; 1150 int i; 1151 1152 for (i = 0; special[i] != NULL; i++) { 1153 if (((sdp = ld_sym_find(special[i], 1154 SYM_NOHASH, 0, ofl)) != NULL) && 1155 (sdp->sd_sym->st_size == 0)) { 1156 if (ld_sym_copy(sdp) == S_ERROR) 1157 return (S_ERROR); 1158 sdp->sd_flags |= FLG_SY_DYNSORT; 1159 } 1160 } 1161 } 1162 1163 /* 1164 * Collect and validate the globals from the internal symbol table. 1165 */ 1166 for (sav = avl_first(&ofl->ofl_symavl); sav; 1167 sav = AVL_NEXT(&ofl->ofl_symavl, sav)) { 1168 Is_desc *isp; 1169 int undeferr = 0; 1170 uchar_t vis; 1171 1172 sdp = sav->sav_symdesc; 1173 1174 /* 1175 * If undefined symbols are allowed ignore any symbols that are 1176 * not needed. 1177 */ 1178 if (!(oflags & FLG_OF_NOUNDEF) && 1179 (sdp->sd_ref == REF_DYN_SEEN)) 1180 continue; 1181 1182 /* 1183 * If the symbol originates from an external or parent mapfile 1184 * reference and hasn't been matched to a reference from a 1185 * relocatable object, ignore it. 1186 */ 1187 if ((sdp->sd_flags & (FLG_SY_EXTERN | FLG_SY_PARENT)) && 1188 ((sdp->sd_flags & FLG_SY_MAPUSED) == 0)) { 1189 sdp->sd_flags |= FLG_SY_INVALID; 1190 continue; 1191 } 1192 1193 sym = sdp->sd_sym; 1194 type = ELF_ST_TYPE(sym->st_info); 1195 1196 /* 1197 * Sanity check TLS. 1198 */ 1199 if ((type == STT_TLS) && (sym->st_size != 0) && 1200 (sym->st_shndx != SHN_UNDEF) && 1201 (sym->st_shndx != SHN_COMMON)) { 1202 Is_desc *isp = sdp->sd_isc; 1203 Ifl_desc *ifl = sdp->sd_file; 1204 1205 if ((isp == 0) || (isp->is_shdr == 0) || 1206 ((isp->is_shdr->sh_flags & SHF_TLS) == 0)) { 1207 eprintf(ofl->ofl_lml, ERR_FATAL, 1208 MSG_INTL(MSG_SYM_TLS), 1209 demangle(sdp->sd_name), ifl->ifl_name); 1210 ofl->ofl_flags |= FLG_OF_FATAL; 1211 continue; 1212 } 1213 } 1214 1215 if ((sdp->sd_flags & FLG_SY_VISIBLE) == 0) 1216 ld_sym_adjust_vis(sdp, ofl); 1217 1218 if ((sdp->sd_flags & FLG_SY_REDUCED) && 1219 (oflags & FLG_OF_PROCRED)) { 1220 DBG_CALL(Dbg_syms_reduce(ofl, DBG_SYM_REDUCE_GLOBAL, 1221 sdp, 0, 0)); 1222 } 1223 1224 /* 1225 * Record any STV_SINGLETON existence. 1226 */ 1227 if ((vis = ELF_ST_VISIBILITY(sym->st_other)) == STV_SINGLETON) 1228 ofl->ofl_dtflags_1 |= DF_1_SINGLETON; 1229 1230 /* 1231 * If building a shared object or executable, and this is a 1232 * non-weak UNDEF symbol with reduced visibility (STV_*), then 1233 * give a fatal error. 1234 */ 1235 if (((oflags & FLG_OF_RELOBJ) == 0) && 1236 (sym->st_shndx == SHN_UNDEF) && 1237 (ELF_ST_BIND(sym->st_info) != STB_WEAK)) { 1238 if (vis && (vis != STV_SINGLETON)) { 1239 sym_undef_entry(ofl, sdp, BNDLOCAL); 1240 ofl->ofl_flags |= FLG_OF_FATAL; 1241 continue; 1242 } 1243 } 1244 1245 /* 1246 * If this symbol is defined in a non-allocatable section, 1247 * reduce it to local symbol. 1248 */ 1249 if (((isp = sdp->sd_isc) != 0) && isp->is_shdr && 1250 ((isp->is_shdr->sh_flags & SHF_ALLOC) == 0)) { 1251 sdp->sd_flags |= FLG_SY_REDUCED; 1252 sdp->sd_flags1 |= FLG_SY1_HIDDEN; 1253 } 1254 1255 /* 1256 * If this symbol originated as a SHN_SUNW_IGNORE, it will have 1257 * been processed as an SHN_UNDEF. Return the symbol to its 1258 * original index for validation, and propagation to the output 1259 * file. 1260 */ 1261 if (sdp->sd_flags1 & FLG_SY1_IGNORE) 1262 sdp->sd_shndx = SHN_SUNW_IGNORE; 1263 1264 if (undef) { 1265 /* 1266 * If a non-weak reference remains undefined, or if a 1267 * mapfile reference is not bound to the relocatable 1268 * objects that make up the object being built, we have 1269 * a fatal error. 1270 * 1271 * The exceptions are symbols which are defined to be 1272 * found in the parent (FLG_SY_PARENT), which is really 1273 * only meaningful for direct binding, or are defined 1274 * external (FLG_SY_EXTERN) so as to suppress -zdefs 1275 * errors. 1276 * 1277 * Register symbols are always allowed to be UNDEF. 1278 * 1279 * Note that we don't include references created via -u 1280 * in the same shared object binding test. This is for 1281 * backward compatibility, in that a number of archive 1282 * makefile rules used -u to cause archive extraction. 1283 * These same rules have been cut and pasted to apply 1284 * to shared objects, and thus although the -u reference 1285 * is redundant, flagging it as fatal could cause some 1286 * build to fail. Also we have documented the use of 1287 * -u as a mechanism to cause binding to weak version 1288 * definitions, thus giving users an error condition 1289 * would be incorrect. 1290 */ 1291 if (!(sdp->sd_flags & FLG_SY_REGSYM) && 1292 ((sym->st_shndx == SHN_UNDEF) && 1293 ((ELF_ST_BIND(sym->st_info) != STB_WEAK) && 1294 ((sdp->sd_flags & 1295 (FLG_SY_PARENT | FLG_SY_EXTERN)) == 0)) || 1296 (((sdp->sd_flags & 1297 (FLG_SY_MAPREF | FLG_SY_MAPUSED)) == 1298 FLG_SY_MAPREF) && 1299 ((sdp->sd_flags1 & (FLG_SY1_HIDDEN | 1300 FLG_SY1_PROTECT)) == 0)))) { 1301 sym_undef_entry(ofl, sdp, UNDEF); 1302 ofl->ofl_flags |= undef; 1303 undeferr = 1; 1304 } 1305 1306 } else { 1307 /* 1308 * For building things like shared objects (or anything 1309 * -znodefs), undefined symbols are allowed. 1310 * 1311 * If a mapfile reference remains undefined the user 1312 * would probably like a warning at least (they've 1313 * usually mis-spelt the reference). Refer to the above 1314 * comments for discussion on -u references, which 1315 * are not tested for in the same manner. 1316 */ 1317 if ((sdp->sd_flags & 1318 (FLG_SY_MAPREF | FLG_SY_MAPUSED)) == 1319 FLG_SY_MAPREF) { 1320 sym_undef_entry(ofl, sdp, UNDEF); 1321 ofl->ofl_flags |= FLG_OF_WARN; 1322 undeferr = 1; 1323 } 1324 } 1325 1326 /* 1327 * If this symbol comes from a dependency mark the dependency 1328 * as required (-z ignore can result in unused dependencies 1329 * being dropped). If we need to record dependency versioning 1330 * information indicate what version of the needed shared object 1331 * this symbol is part of. Flag the symbol as undefined if it 1332 * has not been made available to us. 1333 */ 1334 if ((sdp->sd_ref == REF_DYN_NEED) && 1335 (!(sdp->sd_flags & FLG_SY_REFRSD))) { 1336 sdp->sd_file->ifl_flags |= FLG_IF_DEPREQD; 1337 1338 /* 1339 * Capture that we've bound to a symbol that doesn't 1340 * allow being directly bound to. 1341 */ 1342 if (sdp->sd_flags1 & FLG_SY1_NDIR) 1343 ofl->ofl_flags1 |= FLG_OF1_NDIRECT; 1344 1345 if (sdp->sd_file->ifl_vercnt) { 1346 int vndx; 1347 Ver_index *vip; 1348 1349 vndx = sdp->sd_aux->sa_dverndx; 1350 vip = &sdp->sd_file->ifl_verndx[vndx]; 1351 if (vip->vi_flags & FLG_VER_AVAIL) { 1352 vip->vi_flags |= FLG_VER_REFER; 1353 } else { 1354 sym_undef_entry(ofl, sdp, NOTAVAIL); 1355 ofl->ofl_flags |= FLG_OF_FATAL; 1356 continue; 1357 } 1358 } 1359 } 1360 1361 /* 1362 * Test that we do not bind to symbol supplied from an implicit 1363 * shared object. If a binding is from a weak reference it can 1364 * be ignored. 1365 */ 1366 if (needed && !undeferr && (sdp->sd_flags & FLG_SY_GLOBREF) && 1367 (sdp->sd_ref == REF_DYN_NEED) && 1368 (sdp->sd_flags & FLG_SY_NOTAVAIL)) { 1369 sym_undef_entry(ofl, sdp, IMPLICIT); 1370 ofl->ofl_flags |= needed; 1371 continue; 1372 } 1373 1374 /* 1375 * Test that a symbol isn't going to be reduced to local scope 1376 * which actually wants to bind to a shared object - if so it's 1377 * a fatal error. 1378 */ 1379 if ((sdp->sd_ref == REF_DYN_NEED) && 1380 (sdp->sd_flags1 & (FLG_SY1_HIDDEN | FLG_SY1_PROTECT))) { 1381 sym_undef_entry(ofl, sdp, BNDLOCAL); 1382 ofl->ofl_flags |= FLG_OF_FATAL; 1383 continue; 1384 } 1385 1386 /* 1387 * If the output image is to be versioned then all symbol 1388 * definitions must be associated with a version. 1389 */ 1390 if (verdesc && (sdp->sd_ref == REF_REL_NEED) && 1391 (sym->st_shndx != SHN_UNDEF) && 1392 (!(sdp->sd_flags1 & FLG_SY1_HIDDEN)) && 1393 (sdp->sd_aux->sa_overndx == 0)) { 1394 sym_undef_entry(ofl, sdp, NOVERSION); 1395 ofl->ofl_flags |= verdesc; 1396 continue; 1397 } 1398 1399 /* 1400 * If we don't need the symbol there's no need to process it 1401 * any further. 1402 */ 1403 if (sdp->sd_ref == REF_DYN_SEEN) 1404 continue; 1405 1406 /* 1407 * Calculate the size and alignment requirements for the global 1408 * .bss and .tls sections. If we're building a relocatable 1409 * object only account for scoped COMMON symbols (these will 1410 * be converted to .bss references). 1411 * 1412 * For partially initialized symbol, 1413 * if it is expanded, it goes to sunwdata1. 1414 * if it is local, it goes to .bss. 1415 * if the output is shared object, it goes to .sunwbss. 1416 * 1417 * Also refer to make_mvsections() in sunwmove.c 1418 */ 1419 if ((sym->st_shndx == SHN_COMMON) && 1420 (((oflags & FLG_OF_RELOBJ) == 0) || 1421 ((sdp->sd_flags1 & FLG_SY1_HIDDEN) && 1422 (oflags & FLG_OF_PROCRED)))) { 1423 int countbss = 0; 1424 1425 if (sdp->sd_psyminfo == 0) { 1426 countbss = 1; 1427 } else if ((sdp->sd_flags & FLG_SY_PAREXPN) != 0) { 1428 countbss = 0; 1429 } else if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) { 1430 countbss = 1; 1431 } else if ((ofl->ofl_flags & FLG_OF_SHAROBJ) != 0) { 1432 countbss = 0; 1433 } else 1434 countbss = 1; 1435 1436 if (countbss) { 1437 Xword * size, * align; 1438 1439 if (type != STT_TLS) { 1440 size = &bsssize; 1441 align = &bssalign; 1442 } else { 1443 size = &tlssize; 1444 align = &tlsalign; 1445 } 1446 *size = (Xword)S_ROUND(*size, sym->st_value) + 1447 sym->st_size; 1448 if (sym->st_value > *align) 1449 *align = sym->st_value; 1450 } 1451 } 1452 1453 #if defined(_ELF64) 1454 /* 1455 * Calculate the size and alignment requirement for the global 1456 * .lbss. TLS or partially initialized symbols do not need to be 1457 * considered yet. 1458 */ 1459 if ((ld_targ.t_m.m_mach == EM_AMD64) && 1460 (sym->st_shndx == SHN_X86_64_LCOMMON)) { 1461 lbsssize = (Xword)S_ROUND(lbsssize, sym->st_value) + 1462 sym->st_size; 1463 if (sym->st_value > lbssalign) 1464 lbssalign = sym->st_value; 1465 } 1466 #endif 1467 1468 /* 1469 * If a symbol was referenced via the command line 1470 * (ld -u <>, ...), then this counts as a reference against the 1471 * symbol. Mark any section that symbol is defined in. 1472 */ 1473 if (((isp = sdp->sd_isc) != 0) && 1474 (sdp->sd_flags & FLG_SY_CMDREF)) { 1475 isp->is_flags |= FLG_IS_SECTREF; 1476 isp->is_file->ifl_flags |= FLG_IF_FILEREF; 1477 } 1478 1479 /* 1480 * Update the symbol count and the associated name string size. 1481 */ 1482 if ((sdp->sd_flags1 & FLG_SY1_HIDDEN) && 1483 (oflags & FLG_OF_PROCRED)) { 1484 /* 1485 * If any reductions are being processed, keep a count 1486 * of eliminated symbols, and if the symbol is being 1487 * reduced to local, count it's size for the .symtab. 1488 */ 1489 if (sdp->sd_flags1 & FLG_SY1_ELIM) { 1490 ofl->ofl_elimcnt++; 1491 } else { 1492 ofl->ofl_scopecnt++; 1493 if ((((sdp->sd_flags & FLG_SY_REGSYM) == 0) || 1494 sym->st_name) && (st_insert(ofl->ofl_strtab, 1495 sdp->sd_name) == -1)) 1496 return (S_ERROR); 1497 if (allow_ldynsym && sym->st_name && 1498 ldynsym_symtype[type]) { 1499 ofl->ofl_dynscopecnt++; 1500 if (st_insert(ofl->ofl_dynstrtab, 1501 sdp->sd_name) == -1) 1502 return (S_ERROR); 1503 /* Include it in sort section? */ 1504 DYNSORT_COUNT(sdp, sym, type, ++); 1505 } 1506 } 1507 } else { 1508 ofl->ofl_globcnt++; 1509 1510 /* 1511 * Check to see if this global variable should 1512 * go into a sort section. Sort sections require 1513 * a .SUNW_ldynsym section, so, don't check 1514 * unless a .SUNW_ldynsym is allowed. 1515 */ 1516 if (allow_ldynsym) { 1517 DYNSORT_COUNT(sdp, sym, type, ++); 1518 } 1519 1520 /* 1521 * If global direct bindings are in effect, or this 1522 * symbol has bound to a dependency which was specified 1523 * as requiring direct bindings, and it hasn't 1524 * explicitly been defined as a non-direct binding 1525 * symbol, mark it. 1526 */ 1527 if (((ofl->ofl_dtflags_1 & DF_1_DIRECT) || (isp && 1528 (isp->is_file->ifl_flags & FLG_IF_DIRECT))) && 1529 ((sdp->sd_flags1 & FLG_SY1_NDIR) == 0)) 1530 sdp->sd_flags1 |= FLG_SY1_DIR; 1531 1532 /* 1533 * Insert the symbol name. 1534 */ 1535 if (((sdp->sd_flags & FLG_SY_REGSYM) == 0) || 1536 sym->st_name) { 1537 if (st_insert(ofl->ofl_strtab, 1538 sdp->sd_name) == -1) 1539 return (S_ERROR); 1540 1541 if (!(ofl->ofl_flags & FLG_OF_RELOBJ) && 1542 (st_insert(ofl->ofl_dynstrtab, 1543 sdp->sd_name) == -1)) 1544 return (S_ERROR); 1545 } 1546 1547 /* 1548 * If this section offers a global symbol - record that 1549 * fact. 1550 */ 1551 if (isp) { 1552 isp->is_flags |= FLG_IS_SECTREF; 1553 isp->is_file->ifl_flags |= FLG_IF_FILEREF; 1554 } 1555 } 1556 } 1557 1558 /* 1559 * If we've encountered a fatal error during symbol validation then 1560 * return now. 1561 */ 1562 if (ofl->ofl_flags & FLG_OF_FATAL) 1563 return (1); 1564 1565 /* 1566 * Now that symbol resolution is completed, scan any register symbols. 1567 * From now on, we're only interested in those that contribute to the 1568 * output file. 1569 */ 1570 if (ofl->ofl_regsyms) { 1571 int ndx; 1572 1573 for (ndx = 0; ndx < ofl->ofl_regsymsno; ndx++) { 1574 if ((sdp = ofl->ofl_regsyms[ndx]) == 0) 1575 continue; 1576 if (sdp->sd_ref != REF_REL_NEED) { 1577 ofl->ofl_regsyms[ndx] = 0; 1578 continue; 1579 } 1580 1581 ofl->ofl_regsymcnt++; 1582 if (sdp->sd_sym->st_name == 0) 1583 sdp->sd_name = MSG_ORIG(MSG_STR_EMPTY); 1584 1585 if ((sdp->sd_flags1 & FLG_SY1_HIDDEN) || 1586 (ELF_ST_BIND(sdp->sd_sym->st_info) == STB_LOCAL)) 1587 ofl->ofl_lregsymcnt++; 1588 } 1589 } 1590 1591 /* 1592 * Generate the .bss section now that we know its size and alignment. 1593 */ 1594 if (bsssize || !(oflags & FLG_OF_RELOBJ)) { 1595 if (ld_make_bss(ofl, bsssize, bssalign, MAKE_BSS) == S_ERROR) 1596 return (S_ERROR); 1597 } 1598 if (tlssize) { 1599 if (ld_make_bss(ofl, tlssize, tlsalign, MAKE_TLS) == S_ERROR) 1600 return (S_ERROR); 1601 } 1602 #if defined(_ELF64) 1603 if ((ld_targ.t_m.m_mach == EM_AMD64) && 1604 lbsssize && !(oflags & FLG_OF_RELOBJ)) { 1605 if (ld_make_bss(ofl, lbsssize, lbssalign, MAKE_LBSS) == S_ERROR) 1606 return (S_ERROR); 1607 } 1608 #endif 1609 1610 /* 1611 * Determine what entry point symbol we need, and if found save its 1612 * symbol descriptor so that we can update the ELF header entry with the 1613 * symbols value later (see update_oehdr). Make sure the symbol is 1614 * tagged to ensure its update in case -s is in effect. Use any -e 1615 * option first, or the default entry points `_start' and `main'. 1616 */ 1617 ret = 0; 1618 if (ofl->ofl_entry) { 1619 if ((sdp = 1620 ld_sym_find(ofl->ofl_entry, SYM_NOHASH, 0, ofl)) == NULL) { 1621 eprintf(ofl->ofl_lml, ERR_FATAL, 1622 MSG_INTL(MSG_ARG_NOENTRY), ofl->ofl_entry); 1623 ret++; 1624 } else if (ensure_sym_local(ofl, sdp, 1625 MSG_INTL(MSG_SYM_ENTRY)) != 0) { 1626 ret++; 1627 } else { 1628 ofl->ofl_entry = (void *)sdp; 1629 } 1630 } else if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_START), 1631 SYM_NOHASH, 0, ofl)) != NULL) && (ensure_sym_local(ofl, 1632 sdp, 0) == 0)) { 1633 ofl->ofl_entry = (void *)sdp; 1634 1635 } else if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_MAIN), 1636 SYM_NOHASH, 0, ofl)) != NULL) && (ensure_sym_local(ofl, 1637 sdp, 0) == 0)) { 1638 ofl->ofl_entry = (void *)sdp; 1639 } 1640 1641 /* 1642 * If ld -zdtrace=<sym> was given, then validate that the symbol is 1643 * defined within the current object being built. 1644 */ 1645 if ((sdp = ofl->ofl_dtracesym) != 0) 1646 ret += ensure_sym_local(ofl, sdp, MSG_ORIG(MSG_STR_DTRACE)); 1647 1648 /* 1649 * If any initarray, finiarray or preinitarray functions have been 1650 * requested, make sure they are defined within the current object 1651 * being built. 1652 */ 1653 if (ofl->ofl_initarray.head) { 1654 ret += ensure_array_local(ofl, &ofl->ofl_initarray, 1655 MSG_ORIG(MSG_SYM_INITARRAY)); 1656 } 1657 if (ofl->ofl_finiarray.head) { 1658 ret += ensure_array_local(ofl, &ofl->ofl_finiarray, 1659 MSG_ORIG(MSG_SYM_FINIARRAY)); 1660 } 1661 if (ofl->ofl_preiarray.head) { 1662 ret += ensure_array_local(ofl, &ofl->ofl_preiarray, 1663 MSG_ORIG(MSG_SYM_PREINITARRAY)); 1664 } 1665 1666 if (ret) 1667 return (S_ERROR); 1668 1669 /* 1670 * If we're required to record any needed dependencies versioning 1671 * information calculate it now that all symbols have been validated. 1672 */ 1673 if ((oflags & (FLG_OF_VERNEED | FLG_OF_NOVERSEC)) == FLG_OF_VERNEED) 1674 return (ld_vers_check_need(ofl)); 1675 else 1676 return (1); 1677 } 1678 1679 /* 1680 * qsort(3c) comparison function. As an optimization for associating weak 1681 * symbols to their strong counterparts sort global symbols according to their 1682 * address and binding. 1683 */ 1684 static int 1685 compare(const void * sdpp1, const void * sdpp2) 1686 { 1687 Sym_desc * sdp1 = *((Sym_desc **)sdpp1); 1688 Sym_desc * sdp2 = *((Sym_desc **)sdpp2); 1689 Sym * sym1, * sym2; 1690 uchar_t bind1, bind2; 1691 1692 /* 1693 * Symbol descriptors may be zero, move these to the front of the 1694 * sorted array. 1695 */ 1696 if (sdp1 == 0) 1697 return (-1); 1698 if (sdp2 == 0) 1699 return (1); 1700 1701 sym1 = sdp1->sd_sym; 1702 sym2 = sdp2->sd_sym; 1703 1704 /* 1705 * Compare the symbols value (address). 1706 */ 1707 if (sym1->st_value > sym2->st_value) 1708 return (1); 1709 if (sym1->st_value < sym2->st_value) 1710 return (-1); 1711 1712 bind1 = ELF_ST_BIND(sym1->st_info); 1713 bind2 = ELF_ST_BIND(sym2->st_info); 1714 1715 /* 1716 * If two symbols have the same address place the weak symbol before 1717 * any strong counterpart. 1718 */ 1719 if (bind1 > bind2) 1720 return (-1); 1721 if (bind1 < bind2) 1722 return (1); 1723 1724 return (0); 1725 } 1726 1727 1728 /* 1729 * Issue a MSG_SYM_BADADDR error from ld_sym_process(). This error 1730 * is issued when a symbol address/size is not contained by the 1731 * target section. 1732 * 1733 * Such objects are at least partially corrupt, and the user would 1734 * be well advised to be skeptical of them, and to ask their compiler 1735 * supplier to fix the problem. However, a distinction needs to be 1736 * made between symbols that reference readonly text, and those that 1737 * access writable data. Other than throwing off profiling results, 1738 * the readonly section case is less serious. We have encountered 1739 * such objects in the field. In order to allow existing objects 1740 * to continue working, we issue a warning rather than a fatal error 1741 * if the symbol is against readonly text. Other cases are fatal. 1742 */ 1743 static void 1744 issue_badaddr_msg(Ifl_desc *ifl, Ofl_desc *ofl, Sym_desc *sdp, 1745 Sym *sym, Word shndx) 1746 { 1747 ofl_flag_t flag; 1748 Error err; 1749 const char *msg; 1750 1751 if ((sdp->sd_isc->is_shdr->sh_flags & (SHF_WRITE | SHF_ALLOC)) == 1752 SHF_ALLOC) { 1753 msg = MSG_INTL(MSG_SYM_BADADDR_ROTXT); 1754 flag = FLG_OF_WARN; 1755 err = ERR_WARNING; 1756 } else { 1757 msg = MSG_INTL(MSG_SYM_BADADDR); 1758 flag = FLG_OF_FATAL; 1759 err = ERR_FATAL; 1760 } 1761 1762 eprintf(ofl->ofl_lml, err, msg, demangle(sdp->sd_name), 1763 ifl->ifl_name, shndx, sdp->sd_isc->is_name, 1764 EC_XWORD(sdp->sd_isc->is_shdr->sh_size), 1765 EC_XWORD(sym->st_value), EC_XWORD(sym->st_size)); 1766 ofl->ofl_flags |= flag; 1767 } 1768 1769 1770 /* 1771 * Process the symbol table for the specified input file. At this point all 1772 * input sections from this input file have been assigned an input section 1773 * descriptor which is saved in the `ifl_isdesc' array. 1774 * 1775 * o local symbols are saved (as is) if the input file is a 1776 * relocatable object 1777 * 1778 * o global symbols are added to the linkers internal symbol 1779 * table if they are not already present, otherwise a symbol 1780 * resolution function is called upon to resolve the conflict. 1781 */ 1782 uintptr_t 1783 ld_sym_process(Is_desc *isc, Ifl_desc *ifl, Ofl_desc *ofl) 1784 { 1785 /* 1786 * This macro tests the given symbol to see if it is out of 1787 * range relative to the section it references. 1788 * 1789 * entry: 1790 * - ifl is a relative object (ET_REL) 1791 * _sdp - Symbol descriptor 1792 * _sym - Symbol 1793 * _type - Symbol type 1794 * 1795 * The following are tested: 1796 * - Symbol length is non-zero 1797 * - Symbol type is a type that references code or data 1798 * - Referenced section is not 0 (indicates an UNDEF symbol) 1799 * and is not in the range of special values above SHN_LORESERVE 1800 * (excluding SHN_XINDEX, which is OK). 1801 * - We have a valid section header for the target section 1802 * 1803 * If the above are all true, and the symbol position is not 1804 * contained by the target section, this macro evaluates to 1805 * True (1). Otherwise, False(0). 1806 */ 1807 #define SYM_LOC_BADADDR(_sdp, _sym, _type) \ 1808 (_sym->st_size && dynsymsort_symtype[_type] && \ 1809 (_sym->st_shndx != SHN_UNDEF) && \ 1810 ((_sym->st_shndx < SHN_LORESERVE) || \ 1811 (_sym->st_shndx == SHN_XINDEX)) && \ 1812 _sdp->sd_isc && _sdp->sd_isc->is_shdr && \ 1813 ((_sym->st_value + _sym->st_size) > _sdp->sd_isc->is_shdr->sh_size)) 1814 1815 Conv_inv_buf_t inv_buf; 1816 Sym *sym = (Sym *)isc->is_indata->d_buf; 1817 Word *symshndx = 0; 1818 Shdr *shdr = isc->is_shdr; 1819 Sym_desc *sdp; 1820 size_t strsize; 1821 char *strs; 1822 uchar_t type, bind; 1823 Word ndx, hash, local, total; 1824 Half etype = ifl->ifl_ehdr->e_type; 1825 int etype_rel; 1826 const char *symsecname, *strsecname; 1827 avl_index_t where; 1828 int test_gnu_hidden_bit; 1829 1830 /* 1831 * Its possible that a file may contain more that one symbol table, 1832 * ie. .dynsym and .symtab in a shared library. Only process the first 1833 * table (here, we assume .dynsym comes before .symtab). 1834 */ 1835 if (ifl->ifl_symscnt) 1836 return (1); 1837 1838 if (isc->is_symshndx) 1839 symshndx = isc->is_symshndx->is_indata->d_buf; 1840 1841 DBG_CALL(Dbg_syms_process(ofl->ofl_lml, ifl)); 1842 1843 if (isc->is_name) 1844 symsecname = isc->is_name; 1845 else 1846 symsecname = MSG_ORIG(MSG_STR_EMPTY); 1847 1848 /* 1849 * From the symbol tables section header information determine which 1850 * strtab table is needed to locate the actual symbol names. 1851 */ 1852 if (ifl->ifl_flags & FLG_IF_HSTRTAB) { 1853 ndx = shdr->sh_link; 1854 if ((ndx == 0) || (ndx >= ifl->ifl_shnum)) { 1855 eprintf(ofl->ofl_lml, ERR_FATAL, 1856 MSG_INTL(MSG_FIL_INVSHLINK), 1857 ifl->ifl_name, symsecname, EC_XWORD(ndx)); 1858 return (S_ERROR); 1859 } 1860 strsize = ifl->ifl_isdesc[ndx]->is_shdr->sh_size; 1861 strs = ifl->ifl_isdesc[ndx]->is_indata->d_buf; 1862 if (ifl->ifl_isdesc[ndx]->is_name) 1863 strsecname = ifl->ifl_isdesc[ndx]->is_name; 1864 else 1865 strsecname = MSG_ORIG(MSG_STR_EMPTY); 1866 } else { 1867 /* 1868 * There is no string table section in this input file 1869 * although there are symbols in this symbol table section. 1870 * This means that these symbols do not have names. 1871 * Currently, only scratch register symbols are allowed 1872 * not to have names. 1873 */ 1874 strsize = 0; 1875 strs = (char *)MSG_ORIG(MSG_STR_EMPTY); 1876 strsecname = MSG_ORIG(MSG_STR_EMPTY); 1877 } 1878 1879 /* 1880 * Determine the number of local symbols together with the total 1881 * number we have to process. 1882 */ 1883 total = (Word)(shdr->sh_size / shdr->sh_entsize); 1884 local = shdr->sh_info; 1885 1886 /* 1887 * Allocate a symbol table index array and a local symbol array 1888 * (global symbols are processed and added to the ofl->ofl_symbkt[] 1889 * array). If we are dealing with a relocatable object, allocate the 1890 * local symbol descriptors. If this isn't a relocatable object we 1891 * still have to process any shared object locals to determine if any 1892 * register symbols exist. Although these aren't added to the output 1893 * image, they are used as part of symbol resolution. 1894 */ 1895 if ((ifl->ifl_oldndx = libld_malloc((size_t)(total * 1896 sizeof (Sym_desc *)))) == 0) 1897 return (S_ERROR); 1898 etype_rel = (etype == ET_REL); 1899 if (etype_rel && local) { 1900 if ((ifl->ifl_locs = 1901 libld_calloc(sizeof (Sym_desc), local)) == 0) 1902 return (S_ERROR); 1903 /* LINTED */ 1904 ifl->ifl_locscnt = (Word)local; 1905 } 1906 ifl->ifl_symscnt = total; 1907 1908 /* 1909 * If there are local symbols to save add them to the symbol table 1910 * index array. 1911 */ 1912 if (local) { 1913 int allow_ldynsym = OFL_ALLOW_LDYNSYM(ofl); 1914 for (sym++, ndx = 1; ndx < local; sym++, ndx++) { 1915 Word shndx, sdflags = FLG_SY_CLEAN; 1916 const char *name; 1917 Sym_desc *rsdp; 1918 int shndx_bad = 0; 1919 1920 /* 1921 * Determine and validate the associated section index. 1922 */ 1923 if (symshndx && (sym->st_shndx == SHN_XINDEX)) { 1924 shndx = symshndx[ndx]; 1925 } else if ((shndx = sym->st_shndx) >= SHN_LORESERVE) { 1926 sdflags |= FLG_SY_SPECSEC; 1927 } else if (shndx > ifl->ifl_ehdr->e_shnum) { 1928 /* We need the name before we can issue error */ 1929 shndx_bad = 1; 1930 } 1931 1932 /* 1933 * Check if st_name has a valid value or not. 1934 */ 1935 if ((name = string(ofl, ifl, sym, strs, strsize, ndx, 1936 shndx, symsecname, strsecname, &sdflags)) == 0) { 1937 ofl->ofl_flags |= FLG_OF_FATAL; 1938 continue; 1939 } 1940 1941 /* 1942 * Now that we have the name, if the section index 1943 * was bad, report it. 1944 */ 1945 if (shndx_bad) { 1946 eprintf(ofl->ofl_lml, ERR_WARNING, 1947 MSG_INTL(MSG_SYM_INVSHNDX), 1948 demangle_symname(name, isc->is_name, ndx), 1949 ifl->ifl_name, 1950 conv_sym_shndx(sym->st_shndx, &inv_buf)); 1951 continue; 1952 } 1953 1954 /* 1955 * If this local symbol table originates from a shared 1956 * object, then we're only interested in recording 1957 * register symbols. As local symbol descriptors aren't 1958 * allocated for shared objects, one will be allocated 1959 * to associated with the register symbol. This symbol 1960 * won't become part of the output image, but we must 1961 * process it to test for register conflicts. 1962 */ 1963 rsdp = sdp = 0; 1964 if (sdflags & FLG_SY_REGSYM) { 1965 /* 1966 * The presence of FLG_SY_REGSYM means that 1967 * the pointers in ld_targ.t_ms are non-NULL. 1968 */ 1969 rsdp = (*ld_targ.t_ms.ms_reg_find)(sym, ofl); 1970 if (rsdp != 0) { 1971 /* 1972 * The fact that another register def- 1973 * inition has been found is fatal. 1974 * Call the verification routine to get 1975 * the error message and move on. 1976 */ 1977 (void) (*ld_targ.t_ms.ms_reg_check) 1978 (rsdp, sym, name, ifl, ofl); 1979 continue; 1980 } 1981 1982 if (etype == ET_DYN) { 1983 if ((sdp = libld_calloc( 1984 sizeof (Sym_desc), 1)) == 0) 1985 return (S_ERROR); 1986 sdp->sd_ref = REF_DYN_SEEN; 1987 } 1988 } else if (etype == ET_DYN) 1989 continue; 1990 1991 /* 1992 * Fill in the remaining symbol descriptor information. 1993 */ 1994 if (sdp == 0) { 1995 sdp = &(ifl->ifl_locs[ndx]); 1996 sdp->sd_ref = REF_REL_NEED; 1997 } 1998 if (rsdp == 0) { 1999 sdp->sd_name = name; 2000 sdp->sd_sym = sym; 2001 sdp->sd_shndx = shndx; 2002 sdp->sd_flags = sdflags; 2003 sdp->sd_file = ifl; 2004 ifl->ifl_oldndx[ndx] = sdp; 2005 } 2006 2007 DBG_CALL(Dbg_syms_entry(ofl->ofl_lml, ndx, sdp)); 2008 2009 /* 2010 * Reclassify any SHN_SUNW_IGNORE symbols to SHN_UNDEF 2011 * so as to simplify future processing. 2012 */ 2013 if (sym->st_shndx == SHN_SUNW_IGNORE) { 2014 sdp->sd_shndx = shndx = SHN_UNDEF; 2015 sdp->sd_flags1 |= 2016 (FLG_SY1_IGNORE | FLG_SY1_ELIM); 2017 } 2018 2019 /* 2020 * Process any register symbols. 2021 */ 2022 if (sdp->sd_flags & FLG_SY_REGSYM) { 2023 /* 2024 * Add a diagnostic to indicate we've caught a 2025 * register symbol, as this can be useful if a 2026 * register conflict is later discovered. 2027 */ 2028 DBG_CALL(Dbg_syms_entered(ofl, sym, sdp)); 2029 2030 /* 2031 * If this register symbol hasn't already been 2032 * recorded, enter it now. 2033 * 2034 * The presence of FLG_SY_REGSYM means that 2035 * the pointers in ld_targ.t_ms are non-NULL. 2036 */ 2037 if ((rsdp == 0) && 2038 ((*ld_targ.t_ms.ms_reg_enter)(sdp, ofl) == 2039 0)) 2040 return (S_ERROR); 2041 } 2042 2043 /* 2044 * Assign an input section. 2045 */ 2046 if ((sym->st_shndx != SHN_UNDEF) && 2047 ((sdp->sd_flags & FLG_SY_SPECSEC) == 0)) 2048 sdp->sd_isc = ifl->ifl_isdesc[shndx]; 2049 2050 /* 2051 * If this symbol falls within the range of a section 2052 * being discarded, then discard the symbol itself. 2053 * There is no reason to keep this local symbol. 2054 */ 2055 if (sdp->sd_isc && 2056 (sdp->sd_isc->is_flags & FLG_IS_DISCARD)) { 2057 sdp->sd_flags |= FLG_SY_ISDISC; 2058 DBG_CALL(Dbg_syms_discarded(ofl->ofl_lml, sdp)); 2059 continue; 2060 } 2061 2062 /* 2063 * Skip any section symbols as new versions of these 2064 * will be created. 2065 */ 2066 if ((type = ELF_ST_TYPE(sym->st_info)) == STT_SECTION) { 2067 if (sym->st_shndx == SHN_UNDEF) { 2068 eprintf(ofl->ofl_lml, ERR_WARNING, 2069 MSG_INTL(MSG_SYM_INVSHNDX), 2070 demangle_symname(name, isc->is_name, 2071 ndx), ifl->ifl_name, 2072 conv_sym_shndx(sym->st_shndx, 2073 &inv_buf)); 2074 } 2075 continue; 2076 } 2077 2078 /* 2079 * For a relocatable object, if this symbol is defined 2080 * and has non-zero length and references an address 2081 * within an associated section, then check its extents 2082 * to make sure the section boundaries encompass it. 2083 * If they don't, the ELF file is corrupt. 2084 */ 2085 if (etype_rel && SYM_LOC_BADADDR(sdp, sym, type)) { 2086 issue_badaddr_msg(ifl, ofl, sdp, sym, shndx); 2087 continue; 2088 } 2089 2090 /* 2091 * Sanity check for TLS 2092 */ 2093 if ((sym->st_size != 0) && ((type == STT_TLS) && 2094 (sym->st_shndx != SHN_COMMON))) { 2095 Is_desc *isp = sdp->sd_isc; 2096 2097 if ((isp == 0) || (isp->is_shdr == 0) || 2098 ((isp->is_shdr->sh_flags & SHF_TLS) == 0)) { 2099 eprintf(ofl->ofl_lml, ERR_FATAL, 2100 MSG_INTL(MSG_SYM_TLS), 2101 demangle(sdp->sd_name), 2102 ifl->ifl_name); 2103 ofl->ofl_flags |= FLG_OF_FATAL; 2104 continue; 2105 } 2106 } 2107 2108 /* 2109 * Carry our some basic sanity checks (these are just 2110 * some of the erroneous symbol entries we've come 2111 * across, there's probably a lot more). The symbol 2112 * will not be carried forward to the output file, which 2113 * won't be a problem unless a relocation is required 2114 * against it. 2115 */ 2116 if (((sdp->sd_flags & FLG_SY_SPECSEC) && 2117 ((sym->st_shndx == SHN_COMMON)) || 2118 ((type == STT_FILE) && 2119 (sym->st_shndx != SHN_ABS))) || 2120 (sdp->sd_isc && (sdp->sd_isc->is_osdesc == 0))) { 2121 eprintf(ofl->ofl_lml, ERR_WARNING, 2122 MSG_INTL(MSG_SYM_INVSHNDX), 2123 demangle_symname(name, isc->is_name, ndx), 2124 ifl->ifl_name, 2125 conv_sym_shndx(sym->st_shndx, &inv_buf)); 2126 sdp->sd_isc = NULL; 2127 sdp->sd_flags |= FLG_SY_INVALID; 2128 continue; 2129 } 2130 2131 /* 2132 * As these local symbols will become part of the output 2133 * image, record their number and name string size. 2134 * Globals are counted after all input file processing 2135 * (and hence symbol resolution) is complete during 2136 * sym_validate(). 2137 */ 2138 if (!(ofl->ofl_flags & FLG_OF_REDLSYM)) { 2139 ofl->ofl_locscnt++; 2140 2141 if ((((sdp->sd_flags & FLG_SY_REGSYM) == 0) || 2142 sym->st_name) && (st_insert(ofl->ofl_strtab, 2143 sdp->sd_name) == -1)) 2144 return (S_ERROR); 2145 2146 if (allow_ldynsym && sym->st_name && 2147 ldynsym_symtype[type]) { 2148 ofl->ofl_dynlocscnt++; 2149 if (st_insert(ofl->ofl_dynstrtab, 2150 sdp->sd_name) == -1) 2151 return (S_ERROR); 2152 /* Include it in sort section? */ 2153 DYNSORT_COUNT(sdp, sym, type, ++); 2154 } 2155 } 2156 } 2157 } 2158 2159 /* 2160 * The GNU ld interprets the top bit of the 16-bit Versym value 2161 * (0x8000) as the "hidden" bit. If this bit is set, the linker 2162 * is supposed to act as if that symbol does not exist. The Solaris 2163 * linker does not support this mechanism, or the model of interface 2164 * evolution that it allows, but we honor it in GNU ld produced 2165 * objects in order to interoperate with them. 2166 * 2167 * Determine if we should honor the GNU hidden bit for this file. 2168 */ 2169 test_gnu_hidden_bit = ((ifl->ifl_flags & FLG_IF_GNUVER) != 0) && 2170 (ifl->ifl_versym != NULL); 2171 2172 /* 2173 * Now scan the global symbols entering them in the internal symbol 2174 * table or resolving them as necessary. 2175 */ 2176 sym = (Sym *)isc->is_indata->d_buf; 2177 sym += local; 2178 /* LINTED */ 2179 for (ndx = (int)local; ndx < total; sym++, ndx++) { 2180 const char *name; 2181 Word shndx, sdflags = 0; 2182 int shndx_bad = 0; 2183 2184 /* 2185 * Determine and validate the associated section index. 2186 */ 2187 if (symshndx && (sym->st_shndx == SHN_XINDEX)) { 2188 shndx = symshndx[ndx]; 2189 } else if ((shndx = sym->st_shndx) >= SHN_LORESERVE) { 2190 sdflags |= FLG_SY_SPECSEC; 2191 } else if (shndx > ifl->ifl_ehdr->e_shnum) { 2192 /* We need the name before we can issue error */ 2193 shndx_bad = 1; 2194 } 2195 2196 /* 2197 * Check if st_name has a valid value or not. 2198 */ 2199 if ((name = string(ofl, ifl, sym, strs, strsize, ndx, shndx, 2200 symsecname, strsecname, &sdflags)) == 0) { 2201 ofl->ofl_flags |= FLG_OF_FATAL; 2202 continue; 2203 } 2204 2205 /* 2206 * Now that we have the name, if the section index 2207 * was bad, report it. 2208 */ 2209 if (shndx_bad) { 2210 eprintf(ofl->ofl_lml, ERR_WARNING, 2211 MSG_INTL(MSG_SYM_INVSHNDX), 2212 demangle_symname(name, isc->is_name, ndx), 2213 ifl->ifl_name, 2214 conv_sym_shndx(sym->st_shndx, &inv_buf)); 2215 continue; 2216 } 2217 2218 2219 /* 2220 * Test for the GNU hidden bit, and ignore symbols that 2221 * have it set. 2222 */ 2223 if (test_gnu_hidden_bit && 2224 ((ifl->ifl_versym[ndx] & 0x8000) != 0)) 2225 continue; 2226 2227 /* 2228 * The linker itself will generate symbols for _end, _etext, 2229 * _edata, _DYNAMIC and _PROCEDURE_LINKAGE_TABLE_, so don't 2230 * bother entering these symbols from shared objects. This 2231 * results in some wasted resolution processing, which is hard 2232 * to feel, but if nothing else, pollutes diagnostic relocation 2233 * output. 2234 */ 2235 if (name[0] && (etype == ET_DYN) && (sym->st_size == 0) && 2236 (ELF_ST_TYPE(sym->st_info) == STT_OBJECT) && 2237 (name[0] == '_') && ((name[1] == 'e') || 2238 (name[1] == 'D') || (name[1] == 'P')) && 2239 ((strcmp(name, MSG_ORIG(MSG_SYM_ETEXT_U)) == 0) || 2240 (strcmp(name, MSG_ORIG(MSG_SYM_EDATA_U)) == 0) || 2241 (strcmp(name, MSG_ORIG(MSG_SYM_END_U)) == 0) || 2242 (strcmp(name, MSG_ORIG(MSG_SYM_DYNAMIC_U)) == 0) || 2243 (strcmp(name, MSG_ORIG(MSG_SYM_PLKTBL_U)) == 0))) { 2244 ifl->ifl_oldndx[ndx] = 0; 2245 continue; 2246 } 2247 2248 /* 2249 * Determine and validate the symbols binding. 2250 */ 2251 bind = ELF_ST_BIND(sym->st_info); 2252 if ((bind != STB_GLOBAL) && (bind != STB_WEAK)) { 2253 eprintf(ofl->ofl_lml, ERR_WARNING, 2254 MSG_INTL(MSG_SYM_NONGLOB), 2255 demangle_symname(name, isc->is_name, ndx), 2256 ifl->ifl_name, 2257 conv_sym_info_bind(bind, 0, &inv_buf)); 2258 continue; 2259 } 2260 2261 /* 2262 * If this symbol falls within the range of a section being 2263 * discarded, then discard the symbol itself. 2264 */ 2265 if (((sdflags & FLG_SY_SPECSEC) == 0) && 2266 (sym->st_shndx != SHN_UNDEF)) { 2267 Is_desc *isp; 2268 2269 if (shndx >= ifl->ifl_shnum) { 2270 /* 2271 * Carry our some basic sanity checks 2272 * The symbol will not be carried forward to 2273 * the output file, which won't be a problem 2274 * unless a relocation is required against it. 2275 */ 2276 eprintf(ofl->ofl_lml, ERR_WARNING, 2277 MSG_INTL(MSG_SYM_INVSHNDX), 2278 demangle_symname(name, isc->is_name, ndx), 2279 ifl->ifl_name, 2280 conv_sym_shndx(sym->st_shndx, &inv_buf)); 2281 continue; 2282 } 2283 2284 isp = ifl->ifl_isdesc[shndx]; 2285 if (isp && (isp->is_flags & FLG_IS_DISCARD)) { 2286 if ((sdp = 2287 libld_calloc(sizeof (Sym_desc), 1)) == 0) 2288 return (S_ERROR); 2289 2290 /* 2291 * Create a dummy symbol entry so that if we 2292 * find any references to this discarded symbol 2293 * we can compensate. 2294 */ 2295 sdp->sd_name = name; 2296 sdp->sd_sym = sym; 2297 sdp->sd_file = ifl; 2298 sdp->sd_isc = isp; 2299 sdp->sd_flags = FLG_SY_ISDISC; 2300 ifl->ifl_oldndx[ndx] = sdp; 2301 2302 DBG_CALL(Dbg_syms_discarded(ofl->ofl_lml, sdp)); 2303 continue; 2304 } 2305 } 2306 2307 /* 2308 * If the symbol does not already exist in the internal symbol 2309 * table add it, otherwise resolve the conflict. If the symbol 2310 * from this file is kept, retain its symbol table index for 2311 * possible use in associating a global alias. 2312 */ 2313 /* LINTED */ 2314 hash = (Word)elf_hash((const char *)name); 2315 if ((sdp = ld_sym_find(name, hash, &where, ofl)) == NULL) { 2316 DBG_CALL(Dbg_syms_global(ofl->ofl_lml, ndx, name)); 2317 if ((sdp = ld_sym_enter(name, sym, hash, ifl, ofl, ndx, 2318 shndx, sdflags, 0, &where)) == (Sym_desc *)S_ERROR) 2319 return (S_ERROR); 2320 2321 } else if (ld_sym_resolve(sdp, sym, ifl, ofl, ndx, shndx, 2322 sdflags) == S_ERROR) 2323 return (S_ERROR); 2324 2325 /* 2326 * After we've compared a defined symbol in one shared 2327 * object, flag the symbol so we don't compare it again. 2328 */ 2329 if ((etype == ET_DYN) && (sym->st_shndx != SHN_UNDEF) && 2330 ((sdp->sd_flags & FLG_SY_SOFOUND) == 0)) 2331 sdp->sd_flags |= FLG_SY_SOFOUND; 2332 2333 /* 2334 * If the symbol is accepted from this file retain the symbol 2335 * index for possible use in aliasing. 2336 */ 2337 if (sdp->sd_file == ifl) 2338 sdp->sd_symndx = ndx; 2339 2340 ifl->ifl_oldndx[ndx] = sdp; 2341 2342 /* 2343 * If we've accepted a register symbol, continue to validate 2344 * it. 2345 */ 2346 if (sdp->sd_flags & FLG_SY_REGSYM) { 2347 Sym_desc *rsdp; 2348 2349 /* 2350 * The presence of FLG_SY_REGSYM means that 2351 * the pointers in ld_targ.t_ms are non-NULL. 2352 */ 2353 rsdp = (*ld_targ.t_ms.ms_reg_find)(sdp->sd_sym, ofl); 2354 if (rsdp == 0) { 2355 if ((*ld_targ.t_ms.ms_reg_enter)(sdp, ofl) == 0) 2356 return (S_ERROR); 2357 } else if (rsdp != sdp) { 2358 (void) (*ld_targ.t_ms.ms_reg_check)(rsdp, 2359 sdp->sd_sym, sdp->sd_name, ifl, ofl); 2360 } 2361 } 2362 2363 /* 2364 * For a relocatable object, if this symbol is defined 2365 * and has non-zero length and references an address 2366 * within an associated section, then check its extents 2367 * to make sure the section boundaries encompass it. 2368 * If they don't, the ELF file is corrupt. Note that this 2369 * global symbol may have come from another file to satisfy 2370 * an UNDEF symbol of the same name from this one. In that 2371 * case, we don't check it, because it was already checked 2372 * as part of its own file. 2373 */ 2374 if (etype_rel && (sdp->sd_file == ifl)) { 2375 Sym *tsym = sdp->sd_sym; 2376 2377 if (SYM_LOC_BADADDR(sdp, tsym, 2378 ELF_ST_TYPE(tsym->st_info))) { 2379 issue_badaddr_msg(ifl, ofl, sdp, 2380 tsym, tsym->st_shndx); 2381 continue; 2382 } 2383 } 2384 } 2385 2386 /* 2387 * If this is a shared object scan the globals one more time and 2388 * associate any weak/global associations. This association is needed 2389 * should the weak definition satisfy a reference in the dynamic 2390 * executable: 2391 * 2392 * o if the symbol is a data item it will be copied to the 2393 * executables address space, thus we must also reassociate the 2394 * alias symbol with its new location in the executable. 2395 * 2396 * o if the symbol is a function then we may need to promote the 2397 * symbols binding from undefined weak to undefined, otherwise the 2398 * run-time linker will not generate the correct relocation error 2399 * should the symbol not be found. 2400 * 2401 * The true association between a weak/strong symbol pair is that both 2402 * symbol entries are identical, thus first we created a sorted symbol 2403 * list keyed off of the symbols value (if the value is the same chances 2404 * are the rest of the symbols data is). This list is then scanned for 2405 * weak symbols, and if one is found then any strong association will 2406 * exist in the following entries. Thus we just have to scan one 2407 * (typical single alias) or more (in the uncommon instance of multiple 2408 * weak to strong associations) entries to determine if a match exists. 2409 */ 2410 if ((OFL_ALLOW_LDYNSYM(ofl) || (etype == ET_DYN)) && 2411 (total > local)) { 2412 Sym_desc ** sort; 2413 size_t size = (total - local) * sizeof (Sym_desc *); 2414 2415 if ((sort = libld_malloc(size)) == 0) 2416 return (S_ERROR); 2417 (void) memcpy((void *)sort, &ifl->ifl_oldndx[local], size); 2418 2419 qsort(sort, (total - local), sizeof (Sym_desc *), compare); 2420 2421 for (ndx = 0; ndx < (total - local); ndx++) { 2422 Sym_desc * wsdp = sort[ndx]; 2423 Sym * wsym; 2424 int sndx; 2425 2426 if (wsdp == 0) 2427 continue; 2428 2429 wsym = wsdp->sd_sym; 2430 2431 if ((ELF_ST_BIND(wsym->st_info) != STB_WEAK) || 2432 (wsdp->sd_sym->st_shndx == SHN_UNDEF) || 2433 (wsdp->sd_flags & FLG_SY_SPECSEC)) 2434 continue; 2435 2436 /* 2437 * We have a weak symbol, if it has a strong alias it 2438 * will have been sorted to one of the following sort 2439 * table entries. Note that we could have multiple weak 2440 * symbols aliased to one strong (if this occurs then 2441 * the strong symbol only maintains one alias back to 2442 * the last weak). 2443 */ 2444 for (sndx = ndx + 1; sndx < (total - local); sndx++) { 2445 Sym_desc * ssdp = sort[sndx]; 2446 Sym * ssym; 2447 2448 if (ssdp == 0) 2449 break; 2450 2451 ssym = ssdp->sd_sym; 2452 2453 if (wsym->st_value != ssym->st_value) 2454 break; 2455 2456 if ((ssdp->sd_file == ifl) && 2457 (wsdp->sd_file == ifl) && 2458 (wsym->st_size == ssym->st_size) && 2459 (ssdp->sd_sym->st_shndx != SHN_UNDEF) && 2460 (ELF_ST_BIND(ssym->st_info) != STB_WEAK) && 2461 ((ssdp->sd_flags & FLG_SY_SPECSEC) == 0)) { 2462 int w_dynbits, s_dynbits; 2463 2464 /* 2465 * If a sharable object, set link 2466 * fields so they reference each other 2467 */ 2468 if (etype == ET_DYN) { 2469 ssdp->sd_aux->sa_linkndx = 2470 (Word)wsdp->sd_symndx; 2471 wsdp->sd_aux->sa_linkndx = 2472 (Word)ssdp->sd_symndx; 2473 } 2474 /* 2475 * Determine which of these two symbols 2476 * go into the sort section. If the 2477 * mapfile has made explicit settings 2478 * of the FLG_SY_*DYNSORT flags for both 2479 * symbols, then we do what they say. 2480 * If one has the DYNSORT flags set, 2481 * we set the NODYNSORT bit in the 2482 * other. And if neither has an 2483 * explicit setting, then we favor the 2484 * weak symbol because they usually 2485 * lack the leading underscore. 2486 */ 2487 w_dynbits = wsdp->sd_flags & 2488 (FLG_SY_DYNSORT | FLG_SY_NODYNSORT); 2489 s_dynbits = ssdp->sd_flags & 2490 (FLG_SY_DYNSORT | FLG_SY_NODYNSORT); 2491 if (!(w_dynbits && s_dynbits)) { 2492 if (s_dynbits) { 2493 if (s_dynbits == 2494 FLG_SY_DYNSORT) 2495 wsdp->sd_flags |= 2496 FLG_SY_NODYNSORT; 2497 } else if (w_dynbits != 2498 FLG_SY_NODYNSORT) { 2499 ssdp->sd_flags |= 2500 FLG_SY_NODYNSORT; 2501 } 2502 } 2503 break; 2504 } 2505 } 2506 } 2507 } 2508 return (1); 2509 2510 #undef SYM_LOC_BADADDR 2511 } 2512 2513 /* 2514 * Add an undefined symbol to the symbol table. The reference originates from 2515 * the location identifed by the message id (mid). These references can 2516 * originate from command line options such as -e, -u, -initarray, etc. 2517 * (identified with MSG_INTL(MSG_STR_COMMAND)), or from internally generated 2518 * TLS relocation references (identified with MSG_INTL(MSG_STR_TLSREL)). 2519 */ 2520 Sym_desc * 2521 ld_sym_add_u(const char *name, Ofl_desc *ofl, Msg mid) 2522 { 2523 Sym *sym; 2524 Ifl_desc *ifl = 0, *_ifl; 2525 Sym_desc *sdp; 2526 Word hash; 2527 Listnode *lnp; 2528 avl_index_t where; 2529 const char *reference = MSG_INTL(mid); 2530 2531 /* 2532 * As an optimization, determine whether we've already generated this 2533 * reference. If the symbol doesn't already exist we'll create it. 2534 * Or if the symbol does exist from a different source, we'll resolve 2535 * the conflict. 2536 */ 2537 /* LINTED */ 2538 hash = (Word)elf_hash(name); 2539 if ((sdp = ld_sym_find(name, hash, &where, ofl)) != NULL) { 2540 if ((sdp->sd_sym->st_shndx == SHN_UNDEF) && 2541 (sdp->sd_file->ifl_name == reference)) 2542 return (sdp); 2543 } 2544 2545 /* 2546 * Determine whether a pseudo input file descriptor exists to represent 2547 * the command line, as any global symbol needs an input file descriptor 2548 * during any symbol resolution (refer to map_ifl() which provides a 2549 * similar method for adding symbols from mapfiles). 2550 */ 2551 for (LIST_TRAVERSE(&ofl->ofl_objs, lnp, _ifl)) 2552 if (strcmp(_ifl->ifl_name, reference) == 0) { 2553 ifl = _ifl; 2554 break; 2555 } 2556 2557 /* 2558 * If no descriptor exists create one. 2559 */ 2560 if (ifl == 0) { 2561 if ((ifl = libld_calloc(sizeof (Ifl_desc), 1)) == 2562 (Ifl_desc *)0) 2563 return ((Sym_desc *)S_ERROR); 2564 ifl->ifl_name = reference; 2565 ifl->ifl_flags = FLG_IF_NEEDED | FLG_IF_FILEREF; 2566 if ((ifl->ifl_ehdr = libld_calloc(sizeof (Ehdr), 2567 1)) == 0) 2568 return ((Sym_desc *)S_ERROR); 2569 ifl->ifl_ehdr->e_type = ET_REL; 2570 2571 if (list_appendc(&ofl->ofl_objs, ifl) == 0) 2572 return ((Sym_desc *)S_ERROR); 2573 } 2574 2575 /* 2576 * Allocate a symbol structure and add it to the global symbol table. 2577 */ 2578 if ((sym = libld_calloc(sizeof (Sym), 1)) == 0) 2579 return ((Sym_desc *)S_ERROR); 2580 sym->st_info = ELF_ST_INFO(STB_GLOBAL, STT_NOTYPE); 2581 sym->st_shndx = SHN_UNDEF; 2582 2583 DBG_CALL(Dbg_syms_process(ofl->ofl_lml, ifl)); 2584 if (sdp == NULL) { 2585 DBG_CALL(Dbg_syms_global(ofl->ofl_lml, 0, name)); 2586 if ((sdp = ld_sym_enter(name, sym, hash, ifl, ofl, 0, SHN_UNDEF, 2587 0, 0, &where)) == (Sym_desc *)S_ERROR) 2588 return ((Sym_desc *)S_ERROR); 2589 } else if (ld_sym_resolve(sdp, sym, ifl, ofl, 0, 2590 SHN_UNDEF, 0) == S_ERROR) 2591 return ((Sym_desc *)S_ERROR); 2592 2593 sdp->sd_flags &= ~FLG_SY_CLEAN; 2594 sdp->sd_flags |= FLG_SY_CMDREF; 2595 2596 return (sdp); 2597 } 2598