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, Word symsecndx, const char *symsecname, 80 const char *strsecname, 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 EC_WORD(symsecndx), symsecname, symndx, 89 EC_XWORD(name)); 90 return (NULL); 91 } 92 if (name >= (Word)strsize) { 93 eprintf(ofl->ofl_lml, ERR_FATAL, 94 MSG_INTL(MSG_FIL_EXCSTRTABLE), ifl->ifl_name, 95 EC_WORD(symsecndx), symsecname, symndx, 96 EC_XWORD(name), strsecname, EC_XWORD(strsize)); 97 return (NULL); 98 } 99 } 100 101 /* 102 * Determine if we're dealing with a register and if so validate it. 103 * If it's a scratch register, a fabricated name will be returned. 104 */ 105 if (ld_targ.t_ms.ms_is_regsym != NULL) { 106 const char *regname = (*ld_targ.t_ms.ms_is_regsym)(ofl, ifl, 107 sym, strs, symndx, shndx, symsecname, flags); 108 109 if (regname == (const char *)S_ERROR) { 110 return (NULL); 111 } 112 if (regname) 113 return (regname); 114 } 115 116 /* 117 * If this isn't a register, but we have a global symbol with a null 118 * name, we're not going to be able to hash this, search for it, or 119 * do anything interesting. However, we've been accepting a symbol of 120 * this kind for ages now, so give the user a warning (rather than a 121 * fatal error), just in case this instance exists somewhere in the 122 * world and hasn't, as yet, been a problem. 123 */ 124 if ((name == 0) && (ELF_ST_BIND(sym->st_info) != STB_LOCAL)) { 125 eprintf(ofl->ofl_lml, ERR_WARNING, MSG_INTL(MSG_FIL_NONAMESYM), 126 ifl->ifl_name, EC_WORD(symsecndx), symsecname, symndx, 127 EC_XWORD(name)); 128 } 129 return (strs + name); 130 } 131 132 /* 133 * For producing symbol names strings to use in error messages. 134 * If the symbol has a non-null name, then the string returned by 135 * this function is the output from demangle(), surrounded by 136 * single quotes. For null names, a descriptive string giving 137 * the symbol section and index is generated. 138 * 139 * This function uses an internal static buffer to hold the resulting 140 * string. The value returned is usable by the caller until the next 141 * call, at which point it is overwritten. 142 */ 143 static const char * 144 demangle_symname(const char *name, const char *symtab_name, Word symndx) 145 { 146 #define INIT_BUFSIZE 256 147 148 static char *buf; 149 static size_t bufsize = 0; 150 size_t len; 151 int use_name; 152 153 use_name = (name != NULL) && (*name != '\0'); 154 155 if (use_name) { 156 name = demangle(name); 157 len = strlen(name) + 2; /* Include room for quotes */ 158 } else { 159 name = MSG_ORIG(MSG_STR_EMPTY); 160 len = strlen(symtab_name) + 2 + CONV_INV_BUFSIZE; 161 } 162 len++; /* Null termination */ 163 164 /* If our buffer is too small, double it until it is big enough */ 165 if (len > bufsize) { 166 size_t new_bufsize = bufsize; 167 char *new_buf; 168 169 if (new_bufsize == 0) 170 new_bufsize = INIT_BUFSIZE; 171 while (len > new_bufsize) 172 new_bufsize *= 2; 173 if ((new_buf = libld_malloc(new_bufsize)) == NULL) 174 return (name); 175 buf = new_buf; 176 bufsize = new_bufsize; 177 } 178 179 if (use_name) { 180 (void) snprintf(buf, bufsize, MSG_ORIG(MSG_FMT_SYMNAM), name); 181 } else { 182 (void) snprintf(buf, bufsize, MSG_ORIG(MSG_FMT_NULLSYMNAM), 183 symtab_name, EC_WORD(symndx)); 184 } 185 186 return (buf); 187 188 #undef INIT_BUFSIZE 189 } 190 191 /* 192 * Shared objects can be built that define specific symbols that can not be 193 * directly bound to. These objects have a syminfo section (and an associated 194 * DF_1_NODIRECT dynamic flags entry). Scan this table looking for symbols 195 * that can't be bound to directly, and if this files symbol is presently 196 * referenced, mark it so that we don't directly bind to it. 197 */ 198 uintptr_t 199 ld_sym_nodirect(Is_desc *isp, Ifl_desc *ifl, Ofl_desc *ofl) 200 { 201 Shdr *sifshdr, *symshdr; 202 Syminfo *sifdata; 203 Sym *symdata; 204 char *strdata; 205 ulong_t cnt, _cnt; 206 207 /* 208 * Get the syminfo data, and determine the number of entries. 209 */ 210 sifshdr = isp->is_shdr; 211 sifdata = (Syminfo *)isp->is_indata->d_buf; 212 cnt = sifshdr->sh_size / sifshdr->sh_entsize; 213 214 /* 215 * Get the associated symbol table. 216 */ 217 symshdr = ifl->ifl_isdesc[sifshdr->sh_link]->is_shdr; 218 symdata = ifl->ifl_isdesc[sifshdr->sh_link]->is_indata->d_buf; 219 220 /* 221 * Get the string table associated with the symbol table. 222 */ 223 strdata = ifl->ifl_isdesc[symshdr->sh_link]->is_indata->d_buf; 224 225 /* 226 * Traverse the syminfo data for symbols that can't be directly 227 * bound to. 228 */ 229 for (_cnt = 1, sifdata++; _cnt < cnt; _cnt++, sifdata++) { 230 Sym *sym; 231 char *str; 232 Sym_desc *sdp; 233 234 if ((sifdata->si_flags & SYMINFO_FLG_NOEXTDIRECT) == 0) 235 continue; 236 237 sym = (Sym *)(symdata + _cnt); 238 str = (char *)(strdata + sym->st_name); 239 240 if (sdp = ld_sym_find(str, SYM_NOHASH, 0, ofl)) { 241 if (ifl != sdp->sd_file) 242 continue; 243 244 sdp->sd_flags1 &= ~FLG_SY1_DIR; 245 sdp->sd_flags1 |= FLG_SY1_NDIR; 246 } 247 } 248 return (0); 249 } 250 251 /* 252 * If, during symbol processing, it is necessary to update a local symbols 253 * contents before we have generated the symbol tables in the output image, 254 * create a new symbol structure and copy the original symbol contents. While 255 * we are processing the input files, their local symbols are part of the 256 * read-only mapped image. Commonly, these symbols are copied to the new output 257 * file image and then updated to reflect their new address and any change in 258 * attributes. However, sometimes during relocation counting, it is necessary 259 * to adjust the symbols information. This routine provides for the generation 260 * of a new symbol image so that this update can be performed. 261 * All global symbols are copied to an internal symbol table to improve locality 262 * of reference and hence performance, and thus this copying is not necessary. 263 */ 264 uintptr_t 265 ld_sym_copy(Sym_desc *sdp) 266 { 267 Sym *nsym; 268 269 if (sdp->sd_flags & FLG_SY_CLEAN) { 270 if ((nsym = libld_malloc(sizeof (Sym))) == NULL) 271 return (S_ERROR); 272 *nsym = *(sdp->sd_sym); 273 sdp->sd_sym = nsym; 274 sdp->sd_flags &= ~FLG_SY_CLEAN; 275 } 276 return (1); 277 } 278 279 /* 280 * Finds a given name in the link editors internal symbol table. If no 281 * hash value is specified it is calculated. A pointer to the located 282 * Sym_desc entry is returned, or NULL if the symbol is not found. 283 */ 284 Sym_desc * 285 ld_sym_find(const char *name, Word hash, avl_index_t *where, Ofl_desc *ofl) 286 { 287 Sym_avlnode qsav, *sav; 288 289 if (hash == SYM_NOHASH) 290 /* LINTED */ 291 hash = (Word)elf_hash((const char *)name); 292 qsav.sav_hash = hash; 293 qsav.sav_name = name; 294 295 /* 296 * Perform search for symbol in AVL tree. Note that the 'where' field 297 * is passed in from the caller. If a 'where' is present, it can be 298 * used in subsequent 'ld_sym_enter()' calls if required. 299 */ 300 sav = avl_find(&ofl->ofl_symavl, &qsav, where); 301 302 /* 303 * If symbol was not found in the avl tree, return null to show that. 304 */ 305 if (sav == NULL) 306 return (NULL); 307 308 /* 309 * Return symbol found. 310 */ 311 return (sav->sav_symdesc); 312 } 313 314 /* 315 * Enter a new symbol into the link editors internal symbol table. 316 * If the symbol is from an input file, information regarding the input file 317 * and input section is also recorded. Otherwise (file == NULL) the symbol 318 * has been internally generated (ie. _etext, _edata, etc.). 319 */ 320 Sym_desc * 321 ld_sym_enter(const char *name, Sym *osym, Word hash, Ifl_desc *ifl, 322 Ofl_desc *ofl, Word ndx, Word shndx, Word sdflags, Half sdflags1, 323 avl_index_t *where) 324 { 325 Sym_desc *sdp; 326 Sym_aux *sap; 327 Sym_avlnode *savl; 328 char *_name; 329 Sym *nsym; 330 Half etype; 331 uchar_t vis; 332 avl_index_t _where; 333 334 /* 335 * Establish the file type. 336 */ 337 if (ifl) 338 etype = ifl->ifl_ehdr->e_type; 339 else 340 etype = ET_NONE; 341 342 ofl->ofl_entercnt++; 343 344 /* 345 * Allocate a Sym Descriptor, Auxiliary Descriptor, and a Sym AVLNode - 346 * contiguously. 347 */ 348 if ((savl = libld_calloc(sizeof (Sym_avlnode) + sizeof (Sym_desc) + 349 sizeof (Sym_aux), 1)) == NULL) 350 return ((Sym_desc *)S_ERROR); 351 sdp = (Sym_desc *)((uintptr_t)savl + sizeof (Sym_avlnode)); 352 sap = (Sym_aux *)((uintptr_t)sdp + sizeof (Sym_desc)); 353 354 savl->sav_symdesc = sdp; 355 sdp->sd_file = ifl; 356 sdp->sd_aux = sap; 357 savl->sav_hash = sap->sa_hash = hash; 358 359 /* 360 * Copy the symbol table entry from the input file into the internal 361 * entry and have the symbol descriptor use it. 362 */ 363 sdp->sd_sym = nsym = &sap->sa_sym; 364 *nsym = *osym; 365 sdp->sd_shndx = shndx; 366 sdp->sd_flags |= sdflags; 367 sdp->sd_flags1 |= sdflags1; 368 369 if ((_name = libld_malloc(strlen(name) + 1)) == NULL) 370 return ((Sym_desc *)S_ERROR); 371 savl->sav_name = sdp->sd_name = (const char *)strcpy(_name, name); 372 373 /* 374 * Enter Symbol in AVL tree. 375 */ 376 if (where == 0) { 377 /* LINTED */ 378 Sym_avlnode *_savl; 379 /* 380 * If a previous ld_sym_find() hasn't initialized 'where' do it 381 * now. 382 */ 383 where = &_where; 384 _savl = avl_find(&ofl->ofl_symavl, savl, where); 385 assert(_savl == NULL); 386 } 387 avl_insert(&ofl->ofl_symavl, savl, *where); 388 389 /* 390 * Record the section index. This is possible because the 391 * `ifl_isdesc' table is filled before we start symbol processing. 392 */ 393 if ((sdflags & FLG_SY_SPECSEC) || (nsym->st_shndx == SHN_UNDEF)) 394 sdp->sd_isc = NULL; 395 else { 396 sdp->sd_isc = ifl->ifl_isdesc[shndx]; 397 398 /* 399 * If this symbol is from a relocatable object, make sure that 400 * it is still associated with a section. For example, an 401 * unknown section type (SHT_NULL) would have been rejected on 402 * input with a warning. Here, we make the use of the symbol 403 * fatal. A symbol descriptor is still returned, so that the 404 * caller can continue processing all symbols, and hence flush 405 * out as many error conditions as possible. 406 */ 407 if ((etype == ET_REL) && (sdp->sd_isc == NULL)) { 408 eprintf(ofl->ofl_lml, ERR_FATAL, 409 MSG_INTL(MSG_SYM_INVSEC), name, ifl->ifl_name, 410 EC_XWORD(shndx)); 411 ofl->ofl_flags |= FLG_OF_FATAL; 412 return (sdp); 413 } 414 } 415 416 /* 417 * Mark any COMMON symbols as 'tentative'. 418 */ 419 if (sdflags & FLG_SY_SPECSEC) { 420 if (nsym->st_shndx == SHN_COMMON) 421 sdp->sd_flags |= FLG_SY_TENTSYM; 422 #if defined(_ELF64) 423 else if ((ld_targ.t_m.m_mach == EM_AMD64) && 424 (nsym->st_shndx == SHN_X86_64_LCOMMON)) 425 sdp->sd_flags |= FLG_SY_TENTSYM; 426 #endif 427 } 428 429 /* 430 * Establish the symbols visibility and reference. 431 */ 432 vis = ELF_ST_VISIBILITY(nsym->st_other); 433 434 if ((etype == ET_NONE) || (etype == ET_REL)) { 435 switch (vis) { 436 case STV_DEFAULT: 437 sdp->sd_flags1 |= FLG_SY1_DEFAULT; 438 break; 439 case STV_INTERNAL: 440 case STV_HIDDEN: 441 sdp->sd_flags1 |= FLG_SY1_HIDDEN; 442 break; 443 case STV_PROTECTED: 444 sdp->sd_flags1 |= FLG_SY1_PROTECT; 445 break; 446 case STV_EXPORTED: 447 sdp->sd_flags1 |= FLG_SY1_EXPORT; 448 break; 449 case STV_SINGLETON: 450 sdp->sd_flags1 |= (FLG_SY1_SINGLE | FLG_SY1_NDIR); 451 ofl->ofl_flags1 |= FLG_OF1_NDIRECT; 452 break; 453 case STV_ELIMINATE: 454 sdp->sd_flags1 |= (FLG_SY1_HIDDEN | FLG_SY1_ELIM); 455 break; 456 default: 457 assert(vis <= STV_ELIMINATE); 458 } 459 460 sdp->sd_ref = REF_REL_NEED; 461 462 /* 463 * Under -Bnodirect, all exported interfaces that have not 464 * explicitly been defined protected or directly bound to, are 465 * tagged to prevent direct binding. 466 */ 467 if ((ofl->ofl_flags1 & FLG_OF1_ALNODIR) && 468 ((sdp->sd_flags1 & (FLG_SY1_PROTECT | FLG_SY1_DIR)) == 0) && 469 (nsym->st_shndx != SHN_UNDEF)) { 470 sdp->sd_flags1 |= FLG_SY1_NDIR; 471 } 472 } else { 473 sdp->sd_ref = REF_DYN_SEEN; 474 475 /* 476 * Record the binding file for this symbol in the sa_bindto 477 * field. If this symbol is ever overridden by a REF_REL_NEED 478 * definition, sa_bindto is used when building a 'translator'. 479 */ 480 if (nsym->st_shndx != SHN_UNDEF) 481 sdp->sd_aux->sa_bindto = ifl; 482 483 /* 484 * If this is a protected symbol, remember this. Note, this 485 * state is different from the FLG_SY1_PROTECT used to establish 486 * a symbol definitions visibility. This state is used to warn 487 * against possible copy relocations against this referenced 488 * symbol. 489 */ 490 if (vis == STV_PROTECTED) 491 sdp->sd_flags |= FLG_SY_PROT; 492 493 /* 494 * If this is a SINGLETON definition, then indicate the symbol 495 * can not be directly bound to, and retain the visibility. 496 * This visibility will be inherited by any references made to 497 * this symbol. 498 */ 499 if ((vis == STV_SINGLETON) && (nsym->st_shndx != SHN_UNDEF)) 500 sdp->sd_flags1 |= (FLG_SY1_SINGLE | FLG_SY1_NDIR); 501 502 /* 503 * If the new symbol is from a shared library and is associated 504 * with a SHT_NOBITS section then this symbol originated from a 505 * tentative symbol. 506 */ 507 if (sdp->sd_isc && 508 (sdp->sd_isc->is_shdr->sh_type == SHT_NOBITS)) 509 sdp->sd_flags |= FLG_SY_TENTSYM; 510 } 511 512 /* 513 * Reclassify any SHN_SUNW_IGNORE symbols to SHN_UNDEF so as to 514 * simplify future processing. 515 */ 516 if (nsym->st_shndx == SHN_SUNW_IGNORE) { 517 sdp->sd_shndx = shndx = SHN_UNDEF; 518 sdp->sd_flags |= FLG_SY_REDUCED; 519 sdp->sd_flags1 |= 520 (FLG_SY1_HIDDEN | FLG_SY1_IGNORE | FLG_SY1_ELIM); 521 } 522 523 /* 524 * If this is an undefined, or common symbol from a relocatable object 525 * determine whether it is a global or weak reference (see build_osym(), 526 * where REF_DYN_NEED definitions are returned back to undefines). 527 */ 528 if ((etype == ET_REL) && 529 (ELF_ST_BIND(nsym->st_info) == STB_GLOBAL) && 530 ((nsym->st_shndx == SHN_UNDEF) || ((sdflags & FLG_SY_SPECSEC) && 531 #if defined(_ELF64) 532 ((nsym->st_shndx == SHN_COMMON) || 533 ((ld_targ.t_m.m_mach == EM_AMD64) && 534 (nsym->st_shndx == SHN_X86_64_LCOMMON)))))) 535 #else 536 /* BEGIN CSTYLED */ 537 (nsym->st_shndx == SHN_COMMON)))) 538 /* END CSTYLED */ 539 #endif 540 sdp->sd_flags |= FLG_SY_GLOBREF; 541 542 /* 543 * Record the input filename on the referenced or defined files list 544 * for possible later diagnostics. The `sa_rfile' pointer contains the 545 * name of the file that first referenced this symbol and is used to 546 * generate undefined symbol diagnostics (refer to sym_undef_entry()). 547 * Note that this entry can be overridden if a reference from a 548 * relocatable object is found after a reference from a shared object 549 * (refer to sym_override()). 550 * The `sa_dfiles' list is used to maintain the list of files that 551 * define the same symbol. This list can be used for two reasons: 552 * 553 * - To save the first definition of a symbol that is not available 554 * for this link-edit. 555 * 556 * - To save all definitions of a symbol when the -m option is in 557 * effect. This is optional as it is used to list multiple 558 * (interposed) definitions of a symbol (refer to ldmap_out()), 559 * and can be quite expensive. 560 */ 561 if (nsym->st_shndx == SHN_UNDEF) { 562 sap->sa_rfile = ifl->ifl_name; 563 } else { 564 if (sdp->sd_ref == REF_DYN_SEEN) { 565 /* 566 * A symbol is determined to be unavailable if it 567 * belongs to a version of a shared object that this 568 * user does not wish to use, or if it belongs to an 569 * implicit shared object. 570 */ 571 if (ifl->ifl_vercnt) { 572 Ver_index *vip; 573 Half vndx = ifl->ifl_versym[ndx]; 574 575 sap->sa_dverndx = vndx; 576 vip = &ifl->ifl_verndx[vndx]; 577 if (!(vip->vi_flags & FLG_VER_AVAIL)) { 578 sdp->sd_flags |= FLG_SY_NOTAVAIL; 579 sap->sa_vfile = ifl->ifl_name; 580 } 581 } 582 if (!(ifl->ifl_flags & FLG_IF_NEEDED)) 583 sdp->sd_flags |= FLG_SY_NOTAVAIL; 584 585 } else if (etype == ET_REL) { 586 /* 587 * If this symbol has been obtained from a versioned 588 * input relocatable object then the new symbol must be 589 * promoted to the versioning of the output file. 590 */ 591 if (ifl->ifl_versym) 592 ld_vers_promote(sdp, ndx, ifl, ofl); 593 } 594 595 if ((ofl->ofl_flags & FLG_OF_GENMAP) && 596 ((sdflags & FLG_SY_SPECSEC) == 0)) 597 if (aplist_append(&sap->sa_dfiles, ifl->ifl_name, 598 AL_CNT_SDP_DFILES) == NULL) 599 return ((Sym_desc *)S_ERROR); 600 } 601 602 /* 603 * Provided we're not processing a mapfile, diagnose the entered symbol. 604 * Mapfile processing requires the symbol to be updated with additional 605 * information, therefore the diagnosing of the symbol is deferred until 606 * later (see Dbg_map_symbol()). 607 */ 608 if ((ifl == NULL) || ((ifl->ifl_flags & FLG_IF_MAPFILE) == 0)) 609 DBG_CALL(Dbg_syms_entered(ofl, nsym, sdp)); 610 return (sdp); 611 } 612 613 /* 614 * Add a special symbol to the symbol table. Takes special symbol name with 615 * and without underscores. This routine is called, after all other symbol 616 * resolution has completed, to generate a reserved absolute symbol (the 617 * underscore version). Special symbols are updated with the appropriate 618 * values in update_osym(). If the user has already defined this symbol 619 * issue a warning and leave the symbol as is. If the non-underscore symbol 620 * is referenced then turn it into a weak alias of the underscored symbol. 621 * 622 * The bits in flags_u are OR'd into the flags field of the symbol 623 * for the underscored symbol. 624 * 625 * If this is a global symbol, and it hasn't explicitly been defined as being 626 * directly bound to, indicate that it can't be directly bound to. 627 * Historically, most special symbols only have meaning to the object in which 628 * they exist, however, they've always been global. To ensure compatibility 629 * with any unexpected use presently in effect, ensure these symbols don't get 630 * directly bound to. Note, that establishing this state here isn't sufficient 631 * to create a syminfo table, only if a syminfo table is being created by some 632 * other symbol directives will the nodirect binding be recorded. This ensures 633 * we don't create syminfo sections for all objects we create, as this might add 634 * unnecessary bloat to users who haven't explicitly requested extra symbol 635 * information. 636 */ 637 static uintptr_t 638 sym_add_spec(const char *name, const char *uname, Word sdaux_id, 639 Word flags_u, Half flags1, Ofl_desc *ofl) 640 { 641 Sym_desc *sdp; 642 Sym_desc *usdp; 643 Sym *sym; 644 Word hash; 645 avl_index_t where; 646 647 /* LINTED */ 648 hash = (Word)elf_hash(uname); 649 if (usdp = ld_sym_find(uname, hash, &where, ofl)) { 650 /* 651 * If the underscore symbol exists and is undefined, or was 652 * defined in a shared library, convert it to a local symbol. 653 * Otherwise leave it as is and warn the user. 654 */ 655 if ((usdp->sd_shndx == SHN_UNDEF) || 656 (usdp->sd_ref != REF_REL_NEED)) { 657 usdp->sd_ref = REF_REL_NEED; 658 usdp->sd_shndx = usdp->sd_sym->st_shndx = SHN_ABS; 659 usdp->sd_flags |= FLG_SY_SPECSEC | flags_u; 660 usdp->sd_sym->st_info = 661 ELF_ST_INFO(STB_GLOBAL, STT_OBJECT); 662 usdp->sd_isc = NULL; 663 usdp->sd_sym->st_size = 0; 664 usdp->sd_sym->st_value = 0; 665 /* LINTED */ 666 usdp->sd_aux->sa_symspec = (Half)sdaux_id; 667 668 /* 669 * If a user hasn't specifically indicated that the 670 * scope of this symbol be made local, then leave it 671 * as global (ie. prevent automatic scoping). The GOT 672 * should be defined protected, whereas all other 673 * special symbols are tagged as no-direct. 674 */ 675 if (((usdp->sd_flags1 & FLG_SY1_HIDDEN) == 0) && 676 (flags1 & FLG_SY1_DEFAULT)) { 677 usdp->sd_aux->sa_overndx = VER_NDX_GLOBAL; 678 if (sdaux_id == SDAUX_ID_GOT) { 679 usdp->sd_flags1 &= ~FLG_SY1_NDIR; 680 usdp->sd_flags1 |= FLG_SY1_PROTECT; 681 usdp->sd_sym->st_other = STV_PROTECTED; 682 } else if ( 683 ((usdp->sd_flags1 & FLG_SY1_DIR) == 0) && 684 ((ofl->ofl_flags & FLG_OF_SYMBOLIC) == 0)) { 685 usdp->sd_flags1 |= FLG_SY1_NDIR; 686 } 687 } 688 usdp->sd_flags1 |= flags1; 689 690 /* 691 * If the reference originated from a mapfile ensure 692 * we mark the symbol as used. 693 */ 694 if (usdp->sd_flags & FLG_SY_MAPREF) 695 usdp->sd_flags |= FLG_SY_MAPUSED; 696 697 DBG_CALL(Dbg_syms_updated(ofl, usdp, uname)); 698 } else 699 eprintf(ofl->ofl_lml, ERR_WARNING, 700 MSG_INTL(MSG_SYM_RESERVE), uname, 701 usdp->sd_file->ifl_name); 702 } else { 703 /* 704 * If the symbol does not exist create it. 705 */ 706 if ((sym = libld_calloc(sizeof (Sym), 1)) == NULL) 707 return (S_ERROR); 708 sym->st_shndx = SHN_ABS; 709 sym->st_info = ELF_ST_INFO(STB_GLOBAL, STT_OBJECT); 710 sym->st_size = 0; 711 sym->st_value = 0; 712 DBG_CALL(Dbg_syms_created(ofl->ofl_lml, uname)); 713 if ((usdp = ld_sym_enter(uname, sym, hash, (Ifl_desc *)NULL, 714 ofl, 0, SHN_ABS, FLG_SY_SPECSEC | flags_u, 0, &where)) == 715 (Sym_desc *)S_ERROR) 716 return (S_ERROR); 717 usdp->sd_ref = REF_REL_NEED; 718 /* LINTED */ 719 usdp->sd_aux->sa_symspec = (Half)sdaux_id; 720 721 usdp->sd_aux->sa_overndx = VER_NDX_GLOBAL; 722 723 if (sdaux_id == SDAUX_ID_GOT) { 724 usdp->sd_flags1 |= FLG_SY1_PROTECT; 725 usdp->sd_sym->st_other = STV_PROTECTED; 726 } else if ((flags1 & FLG_SY1_DEFAULT) && 727 ((ofl->ofl_flags & FLG_OF_SYMBOLIC) == 0)) { 728 usdp->sd_flags1 |= FLG_SY1_NDIR; 729 } 730 usdp->sd_flags1 |= flags1; 731 } 732 733 if (name && (sdp = ld_sym_find(name, SYM_NOHASH, 0, ofl)) && 734 (sdp->sd_sym->st_shndx == SHN_UNDEF)) { 735 uchar_t bind; 736 737 /* 738 * If the non-underscore symbol exists and is undefined 739 * convert it to be a local. If the underscore has 740 * sa_symspec set (ie. it was created above) then simulate this 741 * as a weak alias. 742 */ 743 sdp->sd_ref = REF_REL_NEED; 744 sdp->sd_shndx = sdp->sd_sym->st_shndx = SHN_ABS; 745 sdp->sd_flags |= FLG_SY_SPECSEC; 746 sdp->sd_isc = NULL; 747 sdp->sd_sym->st_size = 0; 748 sdp->sd_sym->st_value = 0; 749 /* LINTED */ 750 sdp->sd_aux->sa_symspec = (Half)sdaux_id; 751 if (usdp->sd_aux->sa_symspec) { 752 usdp->sd_aux->sa_linkndx = 0; 753 sdp->sd_aux->sa_linkndx = 0; 754 bind = STB_WEAK; 755 } else 756 bind = STB_GLOBAL; 757 sdp->sd_sym->st_info = ELF_ST_INFO(bind, STT_OBJECT); 758 759 /* 760 * If a user hasn't specifically indicated the scope of this 761 * symbol be made local then leave it as global (ie. prevent 762 * automatic scoping). The GOT should be defined protected, 763 * whereas all other special symbols are tagged as no-direct. 764 */ 765 if (((sdp->sd_flags1 & FLG_SY1_HIDDEN) == 0) && 766 (flags1 & FLG_SY1_DEFAULT)) { 767 sdp->sd_aux->sa_overndx = VER_NDX_GLOBAL; 768 if (sdaux_id == SDAUX_ID_GOT) { 769 sdp->sd_flags1 &= ~FLG_SY1_NDIR; 770 sdp->sd_flags1 |= FLG_SY1_PROTECT; 771 sdp->sd_sym->st_other = STV_PROTECTED; 772 } else if (((sdp->sd_flags1 & FLG_SY1_DIR) == 0) && 773 ((ofl->ofl_flags & FLG_OF_SYMBOLIC) == 0)) { 774 sdp->sd_flags1 |= FLG_SY1_NDIR; 775 } 776 } 777 sdp->sd_flags1 |= flags1; 778 779 /* 780 * If the reference originated from a mapfile ensure 781 * we mark the symbol as used. 782 */ 783 if (sdp->sd_flags & FLG_SY_MAPREF) 784 sdp->sd_flags |= FLG_SY_MAPUSED; 785 786 DBG_CALL(Dbg_syms_updated(ofl, sdp, name)); 787 } 788 return (1); 789 } 790 791 792 /* 793 * Print undefined symbols. 794 */ 795 static Boolean undef_title = TRUE; 796 797 static void 798 sym_undef_title(Ofl_desc *ofl) 799 { 800 eprintf(ofl->ofl_lml, ERR_NONE, MSG_INTL(MSG_SYM_FMT_UNDEF), 801 MSG_INTL(MSG_SYM_UNDEF_ITM_11), 802 MSG_INTL(MSG_SYM_UNDEF_ITM_21), 803 MSG_INTL(MSG_SYM_UNDEF_ITM_12), 804 MSG_INTL(MSG_SYM_UNDEF_ITM_22)); 805 806 undef_title = FALSE; 807 } 808 809 /* 810 * Undefined symbols can fall into one of four types: 811 * 812 * - the symbol is really undefined (SHN_UNDEF). 813 * 814 * - versioning has been enabled, however this symbol has not been assigned 815 * to one of the defined versions. 816 * 817 * - the symbol has been defined by an implicitly supplied library, ie. one 818 * which was encounted because it was NEEDED by another library, rather 819 * than from a command line supplied library which would become the only 820 * dependency of the output file being produced. 821 * 822 * - the symbol has been defined by a version of a shared object that is 823 * not permitted for this link-edit. 824 * 825 * In all cases the file who made the first reference to this symbol will have 826 * been recorded via the `sa_rfile' pointer. 827 */ 828 typedef enum { 829 UNDEF, NOVERSION, IMPLICIT, NOTAVAIL, 830 BNDLOCAL 831 } Type; 832 833 static const Msg format[] = { 834 MSG_SYM_UND_UNDEF, /* MSG_INTL(MSG_SYM_UND_UNDEF) */ 835 MSG_SYM_UND_NOVER, /* MSG_INTL(MSG_SYM_UND_NOVER) */ 836 MSG_SYM_UND_IMPL, /* MSG_INTL(MSG_SYM_UND_IMPL) */ 837 MSG_SYM_UND_NOTA, /* MSG_INTL(MSG_SYM_UND_NOTA) */ 838 MSG_SYM_UND_BNDLOCAL /* MSG_INTL(MSG_SYM_UND_BNDLOCAL) */ 839 }; 840 841 static void 842 sym_undef_entry(Ofl_desc *ofl, Sym_desc *sdp, Type type) 843 { 844 const char *name1, *name2, *name3; 845 Ifl_desc *ifl = sdp->sd_file; 846 Sym_aux *sap = sdp->sd_aux; 847 848 if (undef_title) 849 sym_undef_title(ofl); 850 851 switch (type) { 852 case UNDEF: 853 case BNDLOCAL: 854 name1 = sap->sa_rfile; 855 break; 856 case NOVERSION: 857 name1 = ifl->ifl_name; 858 break; 859 case IMPLICIT: 860 name1 = sap->sa_rfile; 861 name2 = ifl->ifl_name; 862 break; 863 case NOTAVAIL: 864 name1 = sap->sa_rfile; 865 name2 = sap->sa_vfile; 866 name3 = ifl->ifl_verndx[sap->sa_dverndx].vi_name; 867 break; 868 default: 869 return; 870 } 871 872 eprintf(ofl->ofl_lml, ERR_NONE, MSG_INTL(format[type]), 873 demangle(sdp->sd_name), name1, name2, name3); 874 } 875 876 /* 877 * At this point all symbol input processing has been completed, therefore 878 * complete the symbol table entries by generating any necessary internal 879 * symbols. 880 */ 881 uintptr_t 882 ld_sym_spec(Ofl_desc *ofl) 883 { 884 Sym_desc *sdp; 885 886 if (ofl->ofl_flags & FLG_OF_RELOBJ) 887 return (1); 888 889 DBG_CALL(Dbg_syms_spec_title(ofl->ofl_lml)); 890 891 if (sym_add_spec(MSG_ORIG(MSG_SYM_ETEXT), MSG_ORIG(MSG_SYM_ETEXT_U), 892 SDAUX_ID_ETEXT, 0, (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), 893 ofl) == S_ERROR) 894 return (S_ERROR); 895 if (sym_add_spec(MSG_ORIG(MSG_SYM_EDATA), MSG_ORIG(MSG_SYM_EDATA_U), 896 SDAUX_ID_EDATA, 0, (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), 897 ofl) == S_ERROR) 898 return (S_ERROR); 899 if (sym_add_spec(MSG_ORIG(MSG_SYM_END), MSG_ORIG(MSG_SYM_END_U), 900 SDAUX_ID_END, FLG_SY_DYNSORT, (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), 901 ofl) == S_ERROR) 902 return (S_ERROR); 903 if (sym_add_spec(MSG_ORIG(MSG_SYM_L_END), MSG_ORIG(MSG_SYM_L_END_U), 904 SDAUX_ID_END, 0, FLG_SY1_HIDDEN, ofl) == S_ERROR) 905 return (S_ERROR); 906 if (sym_add_spec(MSG_ORIG(MSG_SYM_L_START), MSG_ORIG(MSG_SYM_L_START_U), 907 SDAUX_ID_START, 0, FLG_SY1_HIDDEN, ofl) == S_ERROR) 908 return (S_ERROR); 909 910 /* 911 * Historically we've always produced a _DYNAMIC symbol, even for 912 * static executables (in which case its value will be 0). 913 */ 914 if (sym_add_spec(MSG_ORIG(MSG_SYM_DYNAMIC), MSG_ORIG(MSG_SYM_DYNAMIC_U), 915 SDAUX_ID_DYN, FLG_SY_DYNSORT, (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), 916 ofl) == S_ERROR) 917 return (S_ERROR); 918 919 if (OFL_ALLOW_DYNSYM(ofl)) 920 if (sym_add_spec(MSG_ORIG(MSG_SYM_PLKTBL), 921 MSG_ORIG(MSG_SYM_PLKTBL_U), SDAUX_ID_PLT, 922 FLG_SY_DYNSORT, (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), 923 ofl) == S_ERROR) 924 return (S_ERROR); 925 926 /* 927 * A GOT reference will be accompanied by the associated GOT symbol. 928 * Make sure it gets assigned the appropriate special attributes. 929 */ 930 if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_GOFTBL_U), 931 SYM_NOHASH, 0, ofl)) != 0) && (sdp->sd_ref != REF_DYN_SEEN)) { 932 if (sym_add_spec(MSG_ORIG(MSG_SYM_GOFTBL), 933 MSG_ORIG(MSG_SYM_GOFTBL_U), SDAUX_ID_GOT, FLG_SY_DYNSORT, 934 (FLG_SY1_DEFAULT | FLG_SY1_EXPDEF), ofl) == S_ERROR) 935 return (S_ERROR); 936 } 937 938 return (1); 939 } 940 941 /* 942 * This routine checks to see if a symbols visibility needs to be reduced to 943 * either SYMBOLIC or LOCAL. This routine can be called from either 944 * reloc_init() or sym_validate(). 945 */ 946 void 947 ld_sym_adjust_vis(Sym_desc *sdp, Ofl_desc *ofl) 948 { 949 ofl_flag_t oflags = ofl->ofl_flags; 950 Sym *sym = sdp->sd_sym; 951 952 if ((sdp->sd_ref == REF_REL_NEED) && 953 (sdp->sd_sym->st_shndx != SHN_UNDEF)) { 954 /* 955 * If auto-reduction/elimination is enabled, reduce any 956 * non-versioned global symbols. This routine is called either 957 * from any initial relocation processing that references this 958 * symbol, or from the symbol validation processing. 959 * 960 * A symbol is a candidate for auto-reduction/elimination if: 961 * 962 * . the symbol wasn't explicitly defined within a mapfile 963 * (in which case all the necessary state has been applied 964 * to the symbol), or 965 * . the symbol isn't one of the family of reserved 966 * special symbols (ie. _end, _etext, etc.), or 967 * . the symbol isn't a SINGLETON, or 968 * . the symbol wasn't explicitly defined within a version 969 * definition associated with an input relocatable object. 970 * 971 * Indicate that the symbol has been reduced as it may be 972 * necessary to print these symbols later. 973 */ 974 if ((oflags & (FLG_OF_AUTOLCL | FLG_OF_AUTOELM)) && 975 ((sdp->sd_flags1 & MSK_SY1_NOAUTO) == 0)) { 976 if ((sdp->sd_flags1 & FLG_SY1_HIDDEN) == 0) { 977 sdp->sd_flags |= FLG_SY_REDUCED; 978 sdp->sd_flags1 |= FLG_SY1_HIDDEN; 979 } 980 981 if (oflags & (FLG_OF_REDLSYM | FLG_OF_AUTOELM)) { 982 sdp->sd_flags1 |= FLG_SY1_ELIM; 983 sym->st_other = STV_ELIMINATE | 984 (sym->st_other & ~MSK_SYM_VISIBILITY); 985 } else if (ELF_ST_VISIBILITY(sym->st_other) != 986 STV_INTERNAL) 987 sym->st_other = STV_HIDDEN | 988 (sym->st_other & ~MSK_SYM_VISIBILITY); 989 } 990 991 /* 992 * If -Bsymbolic is in effect, and the symbol hasn't explicitly 993 * been defined nodirect (via a mapfile), then bind the global 994 * symbol symbolically and assign the STV_PROTECTED visibility 995 * attribute. 996 */ 997 if ((oflags & FLG_OF_SYMBOLIC) && 998 ((sdp->sd_flags1 & (FLG_SY1_HIDDEN | FLG_SY1_NDIR)) == 0)) { 999 sdp->sd_flags1 |= FLG_SY1_PROTECT; 1000 if (ELF_ST_VISIBILITY(sym->st_other) == STV_DEFAULT) 1001 sym->st_other = STV_PROTECTED | 1002 (sym->st_other & ~MSK_SYM_VISIBILITY); 1003 } 1004 } 1005 1006 /* 1007 * Indicate that this symbol has had it's visibility checked so that 1008 * we don't need to do this investigation again. 1009 */ 1010 sdp->sd_flags |= FLG_SY_VISIBLE; 1011 } 1012 1013 /* 1014 * Make sure a symbol definition is local to the object being built. 1015 */ 1016 inline static int 1017 ensure_sym_local(Ofl_desc *ofl, Sym_desc *sdp, const char *str) 1018 { 1019 if (sdp->sd_sym->st_shndx == SHN_UNDEF) { 1020 if (str) { 1021 eprintf(ofl->ofl_lml, ERR_FATAL, 1022 MSG_INTL(MSG_SYM_UNDEF), str, 1023 demangle((char *)sdp->sd_name)); 1024 } 1025 return (1); 1026 } 1027 if (sdp->sd_ref != REF_REL_NEED) { 1028 if (str) { 1029 eprintf(ofl->ofl_lml, ERR_FATAL, 1030 MSG_INTL(MSG_SYM_EXTERN), str, 1031 demangle((char *)sdp->sd_name), 1032 sdp->sd_file->ifl_name); 1033 } 1034 return (1); 1035 } 1036 1037 sdp->sd_flags |= FLG_SY_UPREQD; 1038 if (sdp->sd_isc) { 1039 sdp->sd_isc->is_flags |= FLG_IS_SECTREF; 1040 sdp->sd_isc->is_file->ifl_flags |= FLG_IF_FILEREF; 1041 } 1042 return (0); 1043 } 1044 1045 /* 1046 * Make sure all the symbol definitions required for initarray, finiarray, or 1047 * preinitarray's are local to the object being built. 1048 */ 1049 static int 1050 ensure_array_local(Ofl_desc *ofl, APlist *apl, const char *str) 1051 { 1052 Aliste idx; 1053 Sym_desc *sdp; 1054 int ret = 0; 1055 1056 for (APLIST_TRAVERSE(apl, idx, sdp)) 1057 ret += ensure_sym_local(ofl, sdp, str); 1058 1059 return (ret); 1060 } 1061 1062 /* 1063 * After all symbol table input processing has been finished, and all relocation 1064 * counting has been carried out (ie. no more symbols will be read, generated, 1065 * or modified), validate and count the relevant entries: 1066 * 1067 * - check and print any undefined symbols remaining. Note that 1068 * if a symbol has been defined by virtue of the inclusion of 1069 * an implicit shared library, it is still classed as undefined. 1070 * 1071 * - count the number of global needed symbols together with the 1072 * size of their associated name strings (if scoping has been 1073 * indicated these symbols may be reduced to locals). 1074 * 1075 * - establish the size and alignment requirements for the global 1076 * .bss section (the alignment of this section is based on the 1077 * first symbol that it will contain). 1078 */ 1079 uintptr_t 1080 ld_sym_validate(Ofl_desc *ofl) 1081 { 1082 Sym_avlnode *sav; 1083 Sym_desc *sdp; 1084 Sym *sym; 1085 ofl_flag_t oflags = ofl->ofl_flags; 1086 ofl_flag_t undef = 0, needed = 0, verdesc = 0; 1087 Xword bssalign = 0, tlsalign = 0; 1088 Xword bsssize = 0, tlssize = 0; 1089 #if defined(_ELF64) 1090 Xword lbssalign = 0, lbsssize = 0; 1091 #endif 1092 int ret; 1093 int allow_ldynsym; 1094 uchar_t type; 1095 1096 DBG_CALL(Dbg_basic_validate(ofl->ofl_lml)); 1097 1098 /* 1099 * If a symbol is undefined and this link-edit calls for no undefined 1100 * symbols to remain (this is the default case when generating an 1101 * executable but can be enforced for any object using -z defs), the 1102 * symbol is classified as undefined and a fatal error condition will 1103 * be indicated. 1104 * 1105 * If the symbol is undefined and we're creating a shared object with 1106 * the -Bsymbolic flag, then the symbol is also classified as undefined 1107 * and a warning condition will be indicated. 1108 */ 1109 if ((oflags & (FLG_OF_SHAROBJ | FLG_OF_SYMBOLIC)) == 1110 (FLG_OF_SHAROBJ | FLG_OF_SYMBOLIC)) 1111 undef = FLG_OF_WARN; 1112 if (oflags & FLG_OF_NOUNDEF) 1113 undef = FLG_OF_FATAL; 1114 1115 /* 1116 * If the symbol is referenced from an implicitly included shared object 1117 * (ie. it's not on the NEEDED list) then the symbol is also classified 1118 * as undefined and a fatal error condition will be indicated. 1119 */ 1120 if ((oflags & FLG_OF_NOUNDEF) || !(oflags & FLG_OF_SHAROBJ)) 1121 needed = FLG_OF_FATAL; 1122 1123 /* 1124 * If the output image is being versioned all symbol definitions must be 1125 * associated with a version. Any symbol that isn't is classified as 1126 * undefined and a fatal error condition will be indicated. 1127 */ 1128 if ((oflags & FLG_OF_VERDEF) && (ofl->ofl_vercnt > VER_NDX_GLOBAL)) 1129 verdesc = FLG_OF_FATAL; 1130 1131 allow_ldynsym = OFL_ALLOW_LDYNSYM(ofl); 1132 1133 if (allow_ldynsym) { 1134 /* 1135 * Normally, we disallow symbols with 0 size from appearing 1136 * in a dyn[sym|tls]sort section. However, there are some 1137 * symbols that serve special purposes that we want to exempt 1138 * from this rule. Look them up, and set their 1139 * FLG_SY_DYNSORT flag. 1140 */ 1141 static const char *special[] = { 1142 MSG_ORIG(MSG_SYM_INIT_U), /* _init */ 1143 MSG_ORIG(MSG_SYM_FINI_U), /* _fini */ 1144 MSG_ORIG(MSG_SYM_START), /* _start */ 1145 NULL 1146 }; 1147 int i; 1148 1149 for (i = 0; special[i] != NULL; i++) { 1150 if (((sdp = ld_sym_find(special[i], 1151 SYM_NOHASH, 0, ofl)) != NULL) && 1152 (sdp->sd_sym->st_size == 0)) { 1153 if (ld_sym_copy(sdp) == S_ERROR) 1154 return (S_ERROR); 1155 sdp->sd_flags |= FLG_SY_DYNSORT; 1156 } 1157 } 1158 } 1159 1160 /* 1161 * Collect and validate the globals from the internal symbol table. 1162 */ 1163 for (sav = avl_first(&ofl->ofl_symavl); sav; 1164 sav = AVL_NEXT(&ofl->ofl_symavl, sav)) { 1165 Is_desc *isp; 1166 int undeferr = 0; 1167 uchar_t vis; 1168 1169 sdp = sav->sav_symdesc; 1170 1171 /* 1172 * If undefined symbols are allowed ignore any symbols that are 1173 * not needed. 1174 */ 1175 if (!(oflags & FLG_OF_NOUNDEF) && 1176 (sdp->sd_ref == REF_DYN_SEEN)) 1177 continue; 1178 1179 /* 1180 * If the symbol originates from an external or parent mapfile 1181 * reference and hasn't been matched to a reference from a 1182 * relocatable object, ignore it. 1183 */ 1184 if ((sdp->sd_flags & (FLG_SY_EXTERN | FLG_SY_PARENT)) && 1185 ((sdp->sd_flags & FLG_SY_MAPUSED) == 0)) { 1186 sdp->sd_flags |= FLG_SY_INVALID; 1187 continue; 1188 } 1189 1190 sym = sdp->sd_sym; 1191 type = ELF_ST_TYPE(sym->st_info); 1192 1193 /* 1194 * Sanity check TLS. 1195 */ 1196 if ((type == STT_TLS) && (sym->st_size != 0) && 1197 (sym->st_shndx != SHN_UNDEF) && 1198 (sym->st_shndx != SHN_COMMON)) { 1199 Is_desc *isp = sdp->sd_isc; 1200 Ifl_desc *ifl = sdp->sd_file; 1201 1202 if ((isp == NULL) || (isp->is_shdr == NULL) || 1203 ((isp->is_shdr->sh_flags & SHF_TLS) == 0)) { 1204 eprintf(ofl->ofl_lml, ERR_FATAL, 1205 MSG_INTL(MSG_SYM_TLS), 1206 demangle(sdp->sd_name), ifl->ifl_name); 1207 ofl->ofl_flags |= FLG_OF_FATAL; 1208 continue; 1209 } 1210 } 1211 1212 if ((sdp->sd_flags & FLG_SY_VISIBLE) == 0) 1213 ld_sym_adjust_vis(sdp, ofl); 1214 1215 if ((sdp->sd_flags & FLG_SY_REDUCED) && 1216 (oflags & FLG_OF_PROCRED)) { 1217 DBG_CALL(Dbg_syms_reduce(ofl, DBG_SYM_REDUCE_GLOBAL, 1218 sdp, 0, 0)); 1219 } 1220 1221 /* 1222 * Record any STV_SINGLETON existence. 1223 */ 1224 if ((vis = ELF_ST_VISIBILITY(sym->st_other)) == STV_SINGLETON) 1225 ofl->ofl_dtflags_1 |= DF_1_SINGLETON; 1226 1227 /* 1228 * If building a shared object or executable, and this is a 1229 * non-weak UNDEF symbol with reduced visibility (STV_*), then 1230 * give a fatal error. 1231 */ 1232 if (((oflags & FLG_OF_RELOBJ) == 0) && 1233 (sym->st_shndx == SHN_UNDEF) && 1234 (ELF_ST_BIND(sym->st_info) != STB_WEAK)) { 1235 if (vis && (vis != STV_SINGLETON)) { 1236 sym_undef_entry(ofl, sdp, BNDLOCAL); 1237 ofl->ofl_flags |= FLG_OF_FATAL; 1238 continue; 1239 } 1240 } 1241 1242 /* 1243 * If this symbol is defined in a non-allocatable section, 1244 * reduce it to local symbol. 1245 */ 1246 if (((isp = sdp->sd_isc) != 0) && isp->is_shdr && 1247 ((isp->is_shdr->sh_flags & SHF_ALLOC) == 0)) { 1248 sdp->sd_flags |= FLG_SY_REDUCED; 1249 sdp->sd_flags1 |= FLG_SY1_HIDDEN; 1250 } 1251 1252 /* 1253 * If this symbol originated as a SHN_SUNW_IGNORE, it will have 1254 * been processed as an SHN_UNDEF. Return the symbol to its 1255 * original index for validation, and propagation to the output 1256 * file. 1257 */ 1258 if (sdp->sd_flags1 & FLG_SY1_IGNORE) 1259 sdp->sd_shndx = SHN_SUNW_IGNORE; 1260 1261 if (undef) { 1262 /* 1263 * If a non-weak reference remains undefined, or if a 1264 * mapfile reference is not bound to the relocatable 1265 * objects that make up the object being built, we have 1266 * a fatal error. 1267 * 1268 * The exceptions are symbols which are defined to be 1269 * found in the parent (FLG_SY_PARENT), which is really 1270 * only meaningful for direct binding, or are defined 1271 * external (FLG_SY_EXTERN) so as to suppress -zdefs 1272 * errors. 1273 * 1274 * Register symbols are always allowed to be UNDEF. 1275 * 1276 * Note that we don't include references created via -u 1277 * in the same shared object binding test. This is for 1278 * backward compatibility, in that a number of archive 1279 * makefile rules used -u to cause archive extraction. 1280 * These same rules have been cut and pasted to apply 1281 * to shared objects, and thus although the -u reference 1282 * is redundant, flagging it as fatal could cause some 1283 * build to fail. Also we have documented the use of 1284 * -u as a mechanism to cause binding to weak version 1285 * definitions, thus giving users an error condition 1286 * would be incorrect. 1287 */ 1288 if (!(sdp->sd_flags & FLG_SY_REGSYM) && 1289 ((sym->st_shndx == SHN_UNDEF) && 1290 ((ELF_ST_BIND(sym->st_info) != STB_WEAK) && 1291 ((sdp->sd_flags & 1292 (FLG_SY_PARENT | FLG_SY_EXTERN)) == 0)) || 1293 (((sdp->sd_flags & 1294 (FLG_SY_MAPREF | FLG_SY_MAPUSED)) == 1295 FLG_SY_MAPREF) && 1296 ((sdp->sd_flags1 & (FLG_SY1_HIDDEN | 1297 FLG_SY1_PROTECT)) == 0)))) { 1298 sym_undef_entry(ofl, sdp, UNDEF); 1299 ofl->ofl_flags |= undef; 1300 undeferr = 1; 1301 } 1302 1303 } else { 1304 /* 1305 * For building things like shared objects (or anything 1306 * -znodefs), undefined symbols are allowed. 1307 * 1308 * If a mapfile reference remains undefined the user 1309 * would probably like a warning at least (they've 1310 * usually mis-spelt the reference). Refer to the above 1311 * comments for discussion on -u references, which 1312 * are not tested for in the same manner. 1313 */ 1314 if ((sdp->sd_flags & 1315 (FLG_SY_MAPREF | FLG_SY_MAPUSED)) == 1316 FLG_SY_MAPREF) { 1317 sym_undef_entry(ofl, sdp, UNDEF); 1318 ofl->ofl_flags |= FLG_OF_WARN; 1319 undeferr = 1; 1320 } 1321 } 1322 1323 /* 1324 * If this symbol comes from a dependency mark the dependency 1325 * as required (-z ignore can result in unused dependencies 1326 * being dropped). If we need to record dependency versioning 1327 * information indicate what version of the needed shared object 1328 * this symbol is part of. Flag the symbol as undefined if it 1329 * has not been made available to us. 1330 */ 1331 if ((sdp->sd_ref == REF_DYN_NEED) && 1332 (!(sdp->sd_flags & FLG_SY_REFRSD))) { 1333 sdp->sd_file->ifl_flags |= FLG_IF_DEPREQD; 1334 1335 /* 1336 * Capture that we've bound to a symbol that doesn't 1337 * allow being directly bound to. 1338 */ 1339 if (sdp->sd_flags1 & FLG_SY1_NDIR) 1340 ofl->ofl_flags1 |= FLG_OF1_NDIRECT; 1341 1342 if (sdp->sd_file->ifl_vercnt) { 1343 int vndx; 1344 Ver_index *vip; 1345 1346 vndx = sdp->sd_aux->sa_dverndx; 1347 vip = &sdp->sd_file->ifl_verndx[vndx]; 1348 if (vip->vi_flags & FLG_VER_AVAIL) { 1349 vip->vi_flags |= FLG_VER_REFER; 1350 } else { 1351 sym_undef_entry(ofl, sdp, NOTAVAIL); 1352 ofl->ofl_flags |= FLG_OF_FATAL; 1353 continue; 1354 } 1355 } 1356 } 1357 1358 /* 1359 * Test that we do not bind to symbol supplied from an implicit 1360 * shared object. If a binding is from a weak reference it can 1361 * be ignored. 1362 */ 1363 if (needed && !undeferr && (sdp->sd_flags & FLG_SY_GLOBREF) && 1364 (sdp->sd_ref == REF_DYN_NEED) && 1365 (sdp->sd_flags & FLG_SY_NOTAVAIL)) { 1366 sym_undef_entry(ofl, sdp, IMPLICIT); 1367 ofl->ofl_flags |= needed; 1368 continue; 1369 } 1370 1371 /* 1372 * Test that a symbol isn't going to be reduced to local scope 1373 * which actually wants to bind to a shared object - if so it's 1374 * a fatal error. 1375 */ 1376 if ((sdp->sd_ref == REF_DYN_NEED) && 1377 (sdp->sd_flags1 & (FLG_SY1_HIDDEN | FLG_SY1_PROTECT))) { 1378 sym_undef_entry(ofl, sdp, BNDLOCAL); 1379 ofl->ofl_flags |= FLG_OF_FATAL; 1380 continue; 1381 } 1382 1383 /* 1384 * If the output image is to be versioned then all symbol 1385 * definitions must be associated with a version. 1386 */ 1387 if (verdesc && (sdp->sd_ref == REF_REL_NEED) && 1388 (sym->st_shndx != SHN_UNDEF) && 1389 (!(sdp->sd_flags1 & FLG_SY1_HIDDEN)) && 1390 (sdp->sd_aux->sa_overndx == 0)) { 1391 sym_undef_entry(ofl, sdp, NOVERSION); 1392 ofl->ofl_flags |= verdesc; 1393 continue; 1394 } 1395 1396 /* 1397 * If we don't need the symbol there's no need to process it 1398 * any further. 1399 */ 1400 if (sdp->sd_ref == REF_DYN_SEEN) 1401 continue; 1402 1403 /* 1404 * Calculate the size and alignment requirements for the global 1405 * .bss and .tls sections. If we're building a relocatable 1406 * object only account for scoped COMMON symbols (these will 1407 * be converted to .bss references). 1408 * 1409 * When -z nopartial is in effect, partially initialized 1410 * symbols are directed to the special .data section 1411 * created for that purpose (ofl->ofl_isparexpn). 1412 * Otherwise, partially initialized symbols go to .bss. 1413 * 1414 * Also refer to make_mvsections() in sunwmove.c 1415 */ 1416 if ((sym->st_shndx == SHN_COMMON) && 1417 (((oflags & FLG_OF_RELOBJ) == 0) || 1418 ((sdp->sd_flags1 & FLG_SY1_HIDDEN) && 1419 (oflags & FLG_OF_PROCRED)))) { 1420 if ((sdp->sd_move == NULL) || 1421 ((sdp->sd_flags & FLG_SY_PAREXPN) == 0)) { 1422 Xword * size, * align; 1423 1424 if (type != STT_TLS) { 1425 size = &bsssize; 1426 align = &bssalign; 1427 } else { 1428 size = &tlssize; 1429 align = &tlsalign; 1430 } 1431 *size = (Xword)S_ROUND(*size, sym->st_value) + 1432 sym->st_size; 1433 if (sym->st_value > *align) 1434 *align = sym->st_value; 1435 } 1436 } 1437 1438 #if defined(_ELF64) 1439 /* 1440 * Calculate the size and alignment requirement for the global 1441 * .lbss. TLS or partially initialized symbols do not need to be 1442 * considered yet. 1443 */ 1444 if ((ld_targ.t_m.m_mach == EM_AMD64) && 1445 (sym->st_shndx == SHN_X86_64_LCOMMON)) { 1446 lbsssize = (Xword)S_ROUND(lbsssize, sym->st_value) + 1447 sym->st_size; 1448 if (sym->st_value > lbssalign) 1449 lbssalign = sym->st_value; 1450 } 1451 #endif 1452 1453 /* 1454 * If a symbol was referenced via the command line 1455 * (ld -u <>, ...), then this counts as a reference against the 1456 * symbol. Mark any section that symbol is defined in. 1457 */ 1458 if (((isp = sdp->sd_isc) != 0) && 1459 (sdp->sd_flags & FLG_SY_CMDREF)) { 1460 isp->is_flags |= FLG_IS_SECTREF; 1461 isp->is_file->ifl_flags |= FLG_IF_FILEREF; 1462 } 1463 1464 /* 1465 * Update the symbol count and the associated name string size. 1466 */ 1467 if ((sdp->sd_flags1 & FLG_SY1_HIDDEN) && 1468 (oflags & FLG_OF_PROCRED)) { 1469 /* 1470 * If any reductions are being processed, keep a count 1471 * of eliminated symbols, and if the symbol is being 1472 * reduced to local, count it's size for the .symtab. 1473 */ 1474 if (sdp->sd_flags1 & FLG_SY1_ELIM) { 1475 ofl->ofl_elimcnt++; 1476 } else { 1477 ofl->ofl_scopecnt++; 1478 if ((((sdp->sd_flags & FLG_SY_REGSYM) == 0) || 1479 sym->st_name) && (st_insert(ofl->ofl_strtab, 1480 sdp->sd_name) == -1)) 1481 return (S_ERROR); 1482 if (allow_ldynsym && sym->st_name && 1483 ldynsym_symtype[type]) { 1484 ofl->ofl_dynscopecnt++; 1485 if (st_insert(ofl->ofl_dynstrtab, 1486 sdp->sd_name) == -1) 1487 return (S_ERROR); 1488 /* Include it in sort section? */ 1489 DYNSORT_COUNT(sdp, sym, type, ++); 1490 } 1491 } 1492 } else { 1493 ofl->ofl_globcnt++; 1494 1495 /* 1496 * Check to see if this global variable should 1497 * go into a sort section. Sort sections require 1498 * a .SUNW_ldynsym section, so, don't check 1499 * unless a .SUNW_ldynsym is allowed. 1500 */ 1501 if (allow_ldynsym) { 1502 DYNSORT_COUNT(sdp, sym, type, ++); 1503 } 1504 1505 /* 1506 * If global direct bindings are in effect, or this 1507 * symbol has bound to a dependency which was specified 1508 * as requiring direct bindings, and it hasn't 1509 * explicitly been defined as a non-direct binding 1510 * symbol, mark it. 1511 */ 1512 if (((ofl->ofl_dtflags_1 & DF_1_DIRECT) || (isp && 1513 (isp->is_file->ifl_flags & FLG_IF_DIRECT))) && 1514 ((sdp->sd_flags1 & FLG_SY1_NDIR) == 0)) 1515 sdp->sd_flags1 |= FLG_SY1_DIR; 1516 1517 /* 1518 * Insert the symbol name. 1519 */ 1520 if (((sdp->sd_flags & FLG_SY_REGSYM) == 0) || 1521 sym->st_name) { 1522 if (st_insert(ofl->ofl_strtab, 1523 sdp->sd_name) == -1) 1524 return (S_ERROR); 1525 1526 if (!(ofl->ofl_flags & FLG_OF_RELOBJ) && 1527 (st_insert(ofl->ofl_dynstrtab, 1528 sdp->sd_name) == -1)) 1529 return (S_ERROR); 1530 } 1531 1532 /* 1533 * If this section offers a global symbol - record that 1534 * fact. 1535 */ 1536 if (isp) { 1537 isp->is_flags |= FLG_IS_SECTREF; 1538 isp->is_file->ifl_flags |= FLG_IF_FILEREF; 1539 } 1540 } 1541 } 1542 1543 /* 1544 * If we've encountered a fatal error during symbol validation then 1545 * return now. 1546 */ 1547 if (ofl->ofl_flags & FLG_OF_FATAL) 1548 return (1); 1549 1550 /* 1551 * Now that symbol resolution is completed, scan any register symbols. 1552 * From now on, we're only interested in those that contribute to the 1553 * output file. 1554 */ 1555 if (ofl->ofl_regsyms) { 1556 int ndx; 1557 1558 for (ndx = 0; ndx < ofl->ofl_regsymsno; ndx++) { 1559 if ((sdp = ofl->ofl_regsyms[ndx]) == NULL) 1560 continue; 1561 if (sdp->sd_ref != REF_REL_NEED) { 1562 ofl->ofl_regsyms[ndx] = NULL; 1563 continue; 1564 } 1565 1566 ofl->ofl_regsymcnt++; 1567 if (sdp->sd_sym->st_name == 0) 1568 sdp->sd_name = MSG_ORIG(MSG_STR_EMPTY); 1569 1570 if ((sdp->sd_flags1 & FLG_SY1_HIDDEN) || 1571 (ELF_ST_BIND(sdp->sd_sym->st_info) == STB_LOCAL)) 1572 ofl->ofl_lregsymcnt++; 1573 } 1574 } 1575 1576 /* 1577 * Generate the .bss section now that we know its size and alignment. 1578 */ 1579 if (bsssize) { 1580 if (ld_make_bss(ofl, bsssize, bssalign, 1581 ld_targ.t_id.id_bss) == S_ERROR) 1582 return (S_ERROR); 1583 } 1584 if (tlssize) { 1585 if (ld_make_bss(ofl, tlssize, tlsalign, 1586 ld_targ.t_id.id_tlsbss) == S_ERROR) 1587 return (S_ERROR); 1588 } 1589 #if defined(_ELF64) 1590 if ((ld_targ.t_m.m_mach == EM_AMD64) && 1591 lbsssize && !(oflags & FLG_OF_RELOBJ)) { 1592 if (ld_make_bss(ofl, lbsssize, lbssalign, 1593 ld_targ.t_id.id_lbss) == S_ERROR) 1594 return (S_ERROR); 1595 } 1596 #endif 1597 /* 1598 * Determine what entry point symbol we need, and if found save its 1599 * symbol descriptor so that we can update the ELF header entry with the 1600 * symbols value later (see update_oehdr). Make sure the symbol is 1601 * tagged to ensure its update in case -s is in effect. Use any -e 1602 * option first, or the default entry points `_start' and `main'. 1603 */ 1604 ret = 0; 1605 if (ofl->ofl_entry) { 1606 if ((sdp = 1607 ld_sym_find(ofl->ofl_entry, SYM_NOHASH, 0, ofl)) == NULL) { 1608 eprintf(ofl->ofl_lml, ERR_FATAL, 1609 MSG_INTL(MSG_ARG_NOENTRY), ofl->ofl_entry); 1610 ret++; 1611 } else if (ensure_sym_local(ofl, sdp, 1612 MSG_INTL(MSG_SYM_ENTRY)) != 0) { 1613 ret++; 1614 } else { 1615 ofl->ofl_entry = (void *)sdp; 1616 } 1617 } else if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_START), 1618 SYM_NOHASH, 0, ofl)) != NULL) && (ensure_sym_local(ofl, 1619 sdp, 0) == 0)) { 1620 ofl->ofl_entry = (void *)sdp; 1621 1622 } else if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_MAIN), 1623 SYM_NOHASH, 0, ofl)) != NULL) && (ensure_sym_local(ofl, 1624 sdp, 0) == 0)) { 1625 ofl->ofl_entry = (void *)sdp; 1626 } 1627 1628 /* 1629 * If ld -zdtrace=<sym> was given, then validate that the symbol is 1630 * defined within the current object being built. 1631 */ 1632 if ((sdp = ofl->ofl_dtracesym) != 0) 1633 ret += ensure_sym_local(ofl, sdp, MSG_ORIG(MSG_STR_DTRACE)); 1634 1635 /* 1636 * If any initarray, finiarray or preinitarray functions have been 1637 * requested, make sure they are defined within the current object 1638 * being built. 1639 */ 1640 if (ofl->ofl_initarray) { 1641 ret += ensure_array_local(ofl, ofl->ofl_initarray, 1642 MSG_ORIG(MSG_SYM_INITARRAY)); 1643 } 1644 if (ofl->ofl_finiarray) { 1645 ret += ensure_array_local(ofl, ofl->ofl_finiarray, 1646 MSG_ORIG(MSG_SYM_FINIARRAY)); 1647 } 1648 if (ofl->ofl_preiarray) { 1649 ret += ensure_array_local(ofl, ofl->ofl_preiarray, 1650 MSG_ORIG(MSG_SYM_PREINITARRAY)); 1651 } 1652 1653 if (ret) 1654 return (S_ERROR); 1655 1656 /* 1657 * If we're required to record any needed dependencies versioning 1658 * information calculate it now that all symbols have been validated. 1659 */ 1660 if ((oflags & (FLG_OF_VERNEED | FLG_OF_NOVERSEC)) == FLG_OF_VERNEED) 1661 return (ld_vers_check_need(ofl)); 1662 else 1663 return (1); 1664 } 1665 1666 /* 1667 * qsort(3c) comparison function. As an optimization for associating weak 1668 * symbols to their strong counterparts sort global symbols according to their 1669 * section index, address and binding. 1670 */ 1671 static int 1672 compare(const void *sdpp1, const void *sdpp2) 1673 { 1674 Sym_desc *sdp1 = *((Sym_desc **)sdpp1); 1675 Sym_desc *sdp2 = *((Sym_desc **)sdpp2); 1676 Sym *sym1, *sym2; 1677 uchar_t bind1, bind2; 1678 1679 /* 1680 * Symbol descriptors may be zero, move these to the front of the 1681 * sorted array. 1682 */ 1683 if (sdp1 == NULL) 1684 return (-1); 1685 if (sdp2 == NULL) 1686 return (1); 1687 1688 sym1 = sdp1->sd_sym; 1689 sym2 = sdp2->sd_sym; 1690 1691 /* 1692 * Compare the symbols section index. This is important when sorting 1693 * the symbol tables of relocatable objects. In this case, a symbols 1694 * value is the offset within the associated section, and thus many 1695 * symbols can have the same value, but are effectively different 1696 * addresses. 1697 */ 1698 if (sym1->st_shndx > sym2->st_shndx) 1699 return (1); 1700 if (sym1->st_shndx < sym2->st_shndx) 1701 return (-1); 1702 1703 /* 1704 * Compare the symbols value (address). 1705 */ 1706 if (sym1->st_value > sym2->st_value) 1707 return (1); 1708 if (sym1->st_value < sym2->st_value) 1709 return (-1); 1710 1711 bind1 = ELF_ST_BIND(sym1->st_info); 1712 bind2 = ELF_ST_BIND(sym2->st_info); 1713 1714 /* 1715 * If two symbols have the same address place the weak symbol before 1716 * any strong counterpart. 1717 */ 1718 if (bind1 > bind2) 1719 return (-1); 1720 if (bind1 < bind2) 1721 return (1); 1722 1723 return (0); 1724 } 1725 1726 /* 1727 * Issue a MSG_SYM_BADADDR error from ld_sym_process(). This error 1728 * is issued when a symbol address/size is not contained by the 1729 * target section. 1730 * 1731 * Such objects are at least partially corrupt, and the user would 1732 * be well advised to be skeptical of them, and to ask their compiler 1733 * supplier to fix the problem. However, a distinction needs to be 1734 * made between symbols that reference readonly text, and those that 1735 * access writable data. Other than throwing off profiling results, 1736 * the readonly section case is less serious. We have encountered 1737 * such objects in the field. In order to allow existing objects 1738 * to continue working, we issue a warning rather than a fatal error 1739 * if the symbol is against readonly text. Other cases are fatal. 1740 */ 1741 static void 1742 issue_badaddr_msg(Ifl_desc *ifl, Ofl_desc *ofl, Sym_desc *sdp, 1743 Sym *sym, Word shndx) 1744 { 1745 ofl_flag_t flag; 1746 Error err; 1747 const char *msg; 1748 1749 if ((sdp->sd_isc->is_shdr->sh_flags & (SHF_WRITE | SHF_ALLOC)) == 1750 SHF_ALLOC) { 1751 msg = MSG_INTL(MSG_SYM_BADADDR_ROTXT); 1752 flag = FLG_OF_WARN; 1753 err = ERR_WARNING; 1754 } else { 1755 msg = MSG_INTL(MSG_SYM_BADADDR); 1756 flag = FLG_OF_FATAL; 1757 err = ERR_FATAL; 1758 } 1759 1760 eprintf(ofl->ofl_lml, err, msg, demangle(sdp->sd_name), 1761 ifl->ifl_name, shndx, sdp->sd_isc->is_name, 1762 EC_XWORD(sdp->sd_isc->is_shdr->sh_size), 1763 EC_XWORD(sym->st_value), EC_XWORD(sym->st_size)); 1764 ofl->ofl_flags |= flag; 1765 } 1766 1767 1768 /* 1769 * Process the symbol table for the specified input file. At this point all 1770 * input sections from this input file have been assigned an input section 1771 * descriptor which is saved in the `ifl_isdesc' array. 1772 * 1773 * - local symbols are saved (as is) if the input file is a 1774 * relocatable object 1775 * 1776 * - global symbols are added to the linkers internal symbol 1777 * table if they are not already present, otherwise a symbol 1778 * resolution function is called upon to resolve the conflict. 1779 */ 1780 uintptr_t 1781 ld_sym_process(Is_desc *isc, Ifl_desc *ifl, Ofl_desc *ofl) 1782 { 1783 /* 1784 * This macro tests the given symbol to see if it is out of 1785 * range relative to the section it references. 1786 * 1787 * entry: 1788 * - ifl is a relative object (ET_REL) 1789 * _sdp - Symbol descriptor 1790 * _sym - Symbol 1791 * _type - Symbol type 1792 * 1793 * The following are tested: 1794 * - Symbol length is non-zero 1795 * - Symbol type is a type that references code or data 1796 * - Referenced section is not 0 (indicates an UNDEF symbol) 1797 * and is not in the range of special values above SHN_LORESERVE 1798 * (excluding SHN_XINDEX, which is OK). 1799 * - We have a valid section header for the target section 1800 * 1801 * If the above are all true, and the symbol position is not 1802 * contained by the target section, this macro evaluates to 1803 * True (1). Otherwise, False(0). 1804 */ 1805 #define SYM_LOC_BADADDR(_sdp, _sym, _type) \ 1806 (_sym->st_size && dynsymsort_symtype[_type] && \ 1807 (_sym->st_shndx != SHN_UNDEF) && \ 1808 ((_sym->st_shndx < SHN_LORESERVE) || \ 1809 (_sym->st_shndx == SHN_XINDEX)) && \ 1810 _sdp->sd_isc && _sdp->sd_isc->is_shdr && \ 1811 ((_sym->st_value + _sym->st_size) > _sdp->sd_isc->is_shdr->sh_size)) 1812 1813 Conv_inv_buf_t inv_buf; 1814 Sym *sym = (Sym *)isc->is_indata->d_buf; 1815 Word *symshndx = NULL; 1816 Shdr *shdr = isc->is_shdr; 1817 Sym_desc *sdp; 1818 size_t strsize; 1819 char *strs; 1820 uchar_t type, bind; 1821 Word ndx, hash, local, total; 1822 uchar_t osabi = ifl->ifl_ehdr->e_ident[EI_OSABI]; 1823 Half mach = ifl->ifl_ehdr->e_machine; 1824 Half etype = ifl->ifl_ehdr->e_type; 1825 int etype_rel; 1826 const char *symsecname, *strsecname; 1827 Word symsecndx; 1828 avl_index_t where; 1829 int test_gnu_hidden_bit, weak; 1830 1831 /* 1832 * Its possible that a file may contain more that one symbol table, 1833 * ie. .dynsym and .symtab in a shared library. Only process the first 1834 * table (here, we assume .dynsym comes before .symtab). 1835 */ 1836 if (ifl->ifl_symscnt) 1837 return (1); 1838 1839 if (isc->is_symshndx) 1840 symshndx = isc->is_symshndx->is_indata->d_buf; 1841 1842 DBG_CALL(Dbg_syms_process(ofl->ofl_lml, ifl)); 1843 1844 symsecndx = isc->is_scnndx; 1845 if (isc->is_name) 1846 symsecname = isc->is_name; 1847 else 1848 symsecname = MSG_ORIG(MSG_STR_EMPTY); 1849 1850 /* 1851 * From the symbol tables section header information determine which 1852 * strtab table is needed to locate the actual symbol names. 1853 */ 1854 if (ifl->ifl_flags & FLG_IF_HSTRTAB) { 1855 ndx = shdr->sh_link; 1856 if ((ndx == 0) || (ndx >= ifl->ifl_shnum)) { 1857 eprintf(ofl->ofl_lml, ERR_FATAL, 1858 MSG_INTL(MSG_FIL_INVSHLINK), ifl->ifl_name, 1859 EC_WORD(symsecndx), symsecname, EC_XWORD(ndx)); 1860 return (S_ERROR); 1861 } 1862 strsize = ifl->ifl_isdesc[ndx]->is_shdr->sh_size; 1863 strs = ifl->ifl_isdesc[ndx]->is_indata->d_buf; 1864 if (ifl->ifl_isdesc[ndx]->is_name) 1865 strsecname = ifl->ifl_isdesc[ndx]->is_name; 1866 else 1867 strsecname = MSG_ORIG(MSG_STR_EMPTY); 1868 } else { 1869 /* 1870 * There is no string table section in this input file 1871 * although there are symbols in this symbol table section. 1872 * This means that these symbols do not have names. 1873 * Currently, only scratch register symbols are allowed 1874 * not to have names. 1875 */ 1876 strsize = 0; 1877 strs = (char *)MSG_ORIG(MSG_STR_EMPTY); 1878 strsecname = MSG_ORIG(MSG_STR_EMPTY); 1879 } 1880 1881 /* 1882 * Determine the number of local symbols together with the total 1883 * number we have to process. 1884 */ 1885 total = (Word)(shdr->sh_size / shdr->sh_entsize); 1886 local = shdr->sh_info; 1887 1888 /* 1889 * Allocate a symbol table index array and a local symbol array 1890 * (global symbols are processed and added to the ofl->ofl_symbkt[] 1891 * array). If we are dealing with a relocatable object, allocate the 1892 * local symbol descriptors. If this isn't a relocatable object we 1893 * still have to process any shared object locals to determine if any 1894 * register symbols exist. Although these aren't added to the output 1895 * image, they are used as part of symbol resolution. 1896 */ 1897 if ((ifl->ifl_oldndx = libld_malloc((size_t)(total * 1898 sizeof (Sym_desc *)))) == NULL) 1899 return (S_ERROR); 1900 etype_rel = (etype == ET_REL); 1901 if (etype_rel && local) { 1902 if ((ifl->ifl_locs = 1903 libld_calloc(sizeof (Sym_desc), local)) == NULL) 1904 return (S_ERROR); 1905 /* LINTED */ 1906 ifl->ifl_locscnt = (Word)local; 1907 } 1908 ifl->ifl_symscnt = total; 1909 1910 /* 1911 * If there are local symbols to save add them to the symbol table 1912 * index array. 1913 */ 1914 if (local) { 1915 int allow_ldynsym = OFL_ALLOW_LDYNSYM(ofl); 1916 Sym_desc *last_file_sdp = NULL; 1917 int last_file_ndx = 0; 1918 1919 for (sym++, ndx = 1; ndx < local; sym++, ndx++) { 1920 Word shndx, sdflags = FLG_SY_CLEAN; 1921 const char *name; 1922 Sym_desc *rsdp; 1923 int shndx_bad = 0; 1924 int symtab_enter = 1; 1925 1926 /* 1927 * Determine and validate the associated section index. 1928 */ 1929 if (symshndx && (sym->st_shndx == SHN_XINDEX)) { 1930 shndx = symshndx[ndx]; 1931 } else if ((shndx = sym->st_shndx) >= SHN_LORESERVE) { 1932 sdflags |= FLG_SY_SPECSEC; 1933 } else if (shndx > ifl->ifl_ehdr->e_shnum) { 1934 /* We need the name before we can issue error */ 1935 shndx_bad = 1; 1936 } 1937 1938 /* 1939 * Check if st_name has a valid value or not. 1940 */ 1941 if ((name = string(ofl, ifl, sym, strs, strsize, ndx, 1942 shndx, symsecndx, symsecname, strsecname, 1943 &sdflags)) == NULL) { 1944 ofl->ofl_flags |= FLG_OF_FATAL; 1945 continue; 1946 } 1947 1948 /* 1949 * Now that we have the name, if the section index 1950 * was bad, report it. 1951 */ 1952 if (shndx_bad) { 1953 eprintf(ofl->ofl_lml, ERR_WARNING, 1954 MSG_INTL(MSG_SYM_INVSHNDX), 1955 demangle_symname(name, symsecname, ndx), 1956 ifl->ifl_name, 1957 conv_sym_shndx(osabi, mach, sym->st_shndx, 1958 CONV_FMT_DECIMAL, &inv_buf)); 1959 continue; 1960 } 1961 1962 /* 1963 * If this local symbol table originates from a shared 1964 * object, then we're only interested in recording 1965 * register symbols. As local symbol descriptors aren't 1966 * allocated for shared objects, one will be allocated 1967 * to associated with the register symbol. This symbol 1968 * won't become part of the output image, but we must 1969 * process it to test for register conflicts. 1970 */ 1971 rsdp = sdp = 0; 1972 if (sdflags & FLG_SY_REGSYM) { 1973 /* 1974 * The presence of FLG_SY_REGSYM means that 1975 * the pointers in ld_targ.t_ms are non-NULL. 1976 */ 1977 rsdp = (*ld_targ.t_ms.ms_reg_find)(sym, ofl); 1978 if (rsdp != 0) { 1979 /* 1980 * The fact that another register def- 1981 * inition has been found is fatal. 1982 * Call the verification routine to get 1983 * the error message and move on. 1984 */ 1985 (void) (*ld_targ.t_ms.ms_reg_check) 1986 (rsdp, sym, name, ifl, ofl); 1987 continue; 1988 } 1989 1990 if (etype == ET_DYN) { 1991 if ((sdp = libld_calloc( 1992 sizeof (Sym_desc), 1)) == NULL) 1993 return (S_ERROR); 1994 sdp->sd_ref = REF_DYN_SEEN; 1995 1996 /* Will not appear in output object */ 1997 symtab_enter = 0; 1998 } 1999 } else if (etype == ET_DYN) 2000 continue; 2001 2002 /* 2003 * Fill in the remaining symbol descriptor information. 2004 */ 2005 if (sdp == NULL) { 2006 sdp = &(ifl->ifl_locs[ndx]); 2007 sdp->sd_ref = REF_REL_NEED; 2008 } 2009 if (rsdp == NULL) { 2010 sdp->sd_name = name; 2011 sdp->sd_sym = sym; 2012 sdp->sd_shndx = shndx; 2013 sdp->sd_flags = sdflags; 2014 sdp->sd_file = ifl; 2015 ifl->ifl_oldndx[ndx] = sdp; 2016 } 2017 2018 DBG_CALL(Dbg_syms_entry(ofl->ofl_lml, ndx, sdp)); 2019 2020 /* 2021 * Reclassify any SHN_SUNW_IGNORE symbols to SHN_UNDEF 2022 * so as to simplify future processing. 2023 */ 2024 if (sym->st_shndx == SHN_SUNW_IGNORE) { 2025 sdp->sd_shndx = shndx = SHN_UNDEF; 2026 sdp->sd_flags1 |= 2027 (FLG_SY1_IGNORE | FLG_SY1_ELIM); 2028 } 2029 2030 /* 2031 * Process any register symbols. 2032 */ 2033 if (sdp->sd_flags & FLG_SY_REGSYM) { 2034 /* 2035 * Add a diagnostic to indicate we've caught a 2036 * register symbol, as this can be useful if a 2037 * register conflict is later discovered. 2038 */ 2039 DBG_CALL(Dbg_syms_entered(ofl, sym, sdp)); 2040 2041 /* 2042 * If this register symbol hasn't already been 2043 * recorded, enter it now. 2044 * 2045 * The presence of FLG_SY_REGSYM means that 2046 * the pointers in ld_targ.t_ms are non-NULL. 2047 */ 2048 if ((rsdp == NULL) && 2049 ((*ld_targ.t_ms.ms_reg_enter)(sdp, ofl) == 2050 0)) 2051 return (S_ERROR); 2052 } 2053 2054 /* 2055 * Assign an input section. 2056 */ 2057 if ((sym->st_shndx != SHN_UNDEF) && 2058 ((sdp->sd_flags & FLG_SY_SPECSEC) == 0)) 2059 sdp->sd_isc = ifl->ifl_isdesc[shndx]; 2060 2061 /* 2062 * If this symbol falls within the range of a section 2063 * being discarded, then discard the symbol itself. 2064 * There is no reason to keep this local symbol. 2065 */ 2066 if (sdp->sd_isc && 2067 (sdp->sd_isc->is_flags & FLG_IS_DISCARD)) { 2068 sdp->sd_flags |= FLG_SY_ISDISC; 2069 DBG_CALL(Dbg_syms_discarded(ofl->ofl_lml, sdp)); 2070 continue; 2071 } 2072 2073 /* 2074 * Skip any section symbols as new versions of these 2075 * will be created. 2076 */ 2077 if ((type = ELF_ST_TYPE(sym->st_info)) == STT_SECTION) { 2078 if (sym->st_shndx == SHN_UNDEF) { 2079 eprintf(ofl->ofl_lml, ERR_WARNING, 2080 MSG_INTL(MSG_SYM_INVSHNDX), 2081 demangle_symname(name, symsecname, 2082 ndx), ifl->ifl_name, 2083 conv_sym_shndx(osabi, mach, 2084 sym->st_shndx, CONV_FMT_DECIMAL, 2085 &inv_buf)); 2086 } 2087 continue; 2088 } 2089 2090 /* 2091 * For a relocatable object, if this symbol is defined 2092 * and has non-zero length and references an address 2093 * within an associated section, then check its extents 2094 * to make sure the section boundaries encompass it. 2095 * If they don't, the ELF file is corrupt. 2096 */ 2097 if (etype_rel) { 2098 if (SYM_LOC_BADADDR(sdp, sym, type)) { 2099 issue_badaddr_msg(ifl, ofl, sdp, 2100 sym, shndx); 2101 if (ofl->ofl_flags & FLG_OF_FATAL) 2102 continue; 2103 } 2104 2105 /* 2106 * We have observed relocatable objects 2107 * containing identical adjacent STT_FILE 2108 * symbols. Discard any other than the first, 2109 * as they are all equivalent and the extras 2110 * do not add information. 2111 * 2112 * For the purpose of this test, we assume 2113 * that only the symbol type and the string 2114 * table offset (st_name) matter. 2115 */ 2116 if (type == STT_FILE) { 2117 int toss = (last_file_sdp != NULL) && 2118 ((ndx - 1) == last_file_ndx) && 2119 (sym->st_name == 2120 last_file_sdp->sd_sym->st_name); 2121 2122 last_file_sdp = sdp; 2123 last_file_ndx = ndx; 2124 if (toss) { 2125 sdp->sd_flags |= FLG_SY_INVALID; 2126 DBG_CALL(Dbg_syms_dup_discarded( 2127 ofl->ofl_lml, ndx, sdp)); 2128 continue; 2129 } 2130 } 2131 } 2132 2133 2134 /* 2135 * Sanity check for TLS 2136 */ 2137 if ((sym->st_size != 0) && ((type == STT_TLS) && 2138 (sym->st_shndx != SHN_COMMON))) { 2139 Is_desc *isp = sdp->sd_isc; 2140 2141 if ((isp == NULL) || (isp->is_shdr == NULL) || 2142 ((isp->is_shdr->sh_flags & SHF_TLS) == 0)) { 2143 eprintf(ofl->ofl_lml, ERR_FATAL, 2144 MSG_INTL(MSG_SYM_TLS), 2145 demangle(sdp->sd_name), 2146 ifl->ifl_name); 2147 ofl->ofl_flags |= FLG_OF_FATAL; 2148 continue; 2149 } 2150 } 2151 2152 /* 2153 * Carry our some basic sanity checks (these are just 2154 * some of the erroneous symbol entries we've come 2155 * across, there's probably a lot more). The symbol 2156 * will not be carried forward to the output file, which 2157 * won't be a problem unless a relocation is required 2158 * against it. 2159 */ 2160 if (((sdp->sd_flags & FLG_SY_SPECSEC) && 2161 ((sym->st_shndx == SHN_COMMON)) || 2162 ((type == STT_FILE) && 2163 (sym->st_shndx != SHN_ABS))) || 2164 (sdp->sd_isc && (sdp->sd_isc->is_osdesc == NULL))) { 2165 eprintf(ofl->ofl_lml, ERR_WARNING, 2166 MSG_INTL(MSG_SYM_INVSHNDX), 2167 demangle_symname(name, symsecname, ndx), 2168 ifl->ifl_name, 2169 conv_sym_shndx(osabi, mach, sym->st_shndx, 2170 CONV_FMT_DECIMAL, &inv_buf)); 2171 sdp->sd_isc = NULL; 2172 sdp->sd_flags |= FLG_SY_INVALID; 2173 continue; 2174 } 2175 2176 /* 2177 * As these local symbols will become part of the output 2178 * image, record their number and name string size. 2179 * Globals are counted after all input file processing 2180 * (and hence symbol resolution) is complete during 2181 * sym_validate(). 2182 */ 2183 if (!(ofl->ofl_flags & FLG_OF_REDLSYM) && 2184 symtab_enter) { 2185 ofl->ofl_locscnt++; 2186 2187 if ((((sdp->sd_flags & FLG_SY_REGSYM) == 0) || 2188 sym->st_name) && (st_insert(ofl->ofl_strtab, 2189 sdp->sd_name) == -1)) 2190 return (S_ERROR); 2191 2192 if (allow_ldynsym && sym->st_name && 2193 ldynsym_symtype[type]) { 2194 ofl->ofl_dynlocscnt++; 2195 if (st_insert(ofl->ofl_dynstrtab, 2196 sdp->sd_name) == -1) 2197 return (S_ERROR); 2198 /* Include it in sort section? */ 2199 DYNSORT_COUNT(sdp, sym, type, ++); 2200 } 2201 } 2202 } 2203 } 2204 2205 /* 2206 * The GNU ld interprets the top bit of the 16-bit Versym value 2207 * (0x8000) as the "hidden" bit. If this bit is set, the linker 2208 * is supposed to act as if that symbol does not exist. The Solaris 2209 * linker does not support this mechanism, or the model of interface 2210 * evolution that it allows, but we honor it in GNU ld produced 2211 * objects in order to interoperate with them. 2212 * 2213 * Determine if we should honor the GNU hidden bit for this file. 2214 */ 2215 test_gnu_hidden_bit = ((ifl->ifl_flags & FLG_IF_GNUVER) != 0) && 2216 (ifl->ifl_versym != NULL); 2217 2218 /* 2219 * Now scan the global symbols entering them in the internal symbol 2220 * table or resolving them as necessary. 2221 */ 2222 sym = (Sym *)isc->is_indata->d_buf; 2223 sym += local; 2224 weak = 0; 2225 /* LINTED */ 2226 for (ndx = (int)local; ndx < total; sym++, ndx++) { 2227 const char *name; 2228 Word shndx, sdflags = 0; 2229 int shndx_bad = 0; 2230 2231 /* 2232 * Determine and validate the associated section index. 2233 */ 2234 if (symshndx && (sym->st_shndx == SHN_XINDEX)) { 2235 shndx = symshndx[ndx]; 2236 } else if ((shndx = sym->st_shndx) >= SHN_LORESERVE) { 2237 sdflags |= FLG_SY_SPECSEC; 2238 } else if (shndx > ifl->ifl_ehdr->e_shnum) { 2239 /* We need the name before we can issue error */ 2240 shndx_bad = 1; 2241 } 2242 2243 /* 2244 * Check if st_name has a valid value or not. 2245 */ 2246 if ((name = string(ofl, ifl, sym, strs, strsize, ndx, shndx, 2247 symsecndx, symsecname, strsecname, &sdflags)) == NULL) { 2248 ofl->ofl_flags |= FLG_OF_FATAL; 2249 continue; 2250 } 2251 2252 /* 2253 * Now that we have the name, if the section index 2254 * was bad, report it. 2255 */ 2256 if (shndx_bad) { 2257 eprintf(ofl->ofl_lml, ERR_WARNING, 2258 MSG_INTL(MSG_SYM_INVSHNDX), 2259 demangle_symname(name, symsecname, ndx), 2260 ifl->ifl_name, 2261 conv_sym_shndx(osabi, mach, sym->st_shndx, 2262 CONV_FMT_DECIMAL, &inv_buf)); 2263 continue; 2264 } 2265 2266 2267 /* 2268 * Test for the GNU hidden bit, and ignore symbols that 2269 * have it set. 2270 */ 2271 if (test_gnu_hidden_bit && 2272 ((ifl->ifl_versym[ndx] & 0x8000) != 0)) 2273 continue; 2274 2275 /* 2276 * The linker itself will generate symbols for _end, _etext, 2277 * _edata, _DYNAMIC and _PROCEDURE_LINKAGE_TABLE_, so don't 2278 * bother entering these symbols from shared objects. This 2279 * results in some wasted resolution processing, which is hard 2280 * to feel, but if nothing else, pollutes diagnostic relocation 2281 * output. 2282 */ 2283 if (name[0] && (etype == ET_DYN) && (sym->st_size == 0) && 2284 (ELF_ST_TYPE(sym->st_info) == STT_OBJECT) && 2285 (name[0] == '_') && ((name[1] == 'e') || 2286 (name[1] == 'D') || (name[1] == 'P')) && 2287 ((strcmp(name, MSG_ORIG(MSG_SYM_ETEXT_U)) == 0) || 2288 (strcmp(name, MSG_ORIG(MSG_SYM_EDATA_U)) == 0) || 2289 (strcmp(name, MSG_ORIG(MSG_SYM_END_U)) == 0) || 2290 (strcmp(name, MSG_ORIG(MSG_SYM_DYNAMIC_U)) == 0) || 2291 (strcmp(name, MSG_ORIG(MSG_SYM_PLKTBL_U)) == 0))) { 2292 ifl->ifl_oldndx[ndx] = 0; 2293 continue; 2294 } 2295 2296 /* 2297 * Determine and validate the symbols binding. 2298 */ 2299 bind = ELF_ST_BIND(sym->st_info); 2300 if ((bind != STB_GLOBAL) && (bind != STB_WEAK)) { 2301 eprintf(ofl->ofl_lml, ERR_WARNING, 2302 MSG_INTL(MSG_SYM_NONGLOB), 2303 demangle_symname(name, symsecname, ndx), 2304 ifl->ifl_name, 2305 conv_sym_info_bind(bind, 0, &inv_buf)); 2306 continue; 2307 } 2308 if (bind == STB_WEAK) 2309 weak++; 2310 2311 /* 2312 * If this symbol falls within the range of a section being 2313 * discarded, then discard the symbol itself. 2314 */ 2315 if (((sdflags & FLG_SY_SPECSEC) == 0) && 2316 (sym->st_shndx != SHN_UNDEF)) { 2317 Is_desc *isp; 2318 2319 if (shndx >= ifl->ifl_shnum) { 2320 /* 2321 * Carry our some basic sanity checks 2322 * The symbol will not be carried forward to 2323 * the output file, which won't be a problem 2324 * unless a relocation is required against it. 2325 */ 2326 eprintf(ofl->ofl_lml, ERR_WARNING, 2327 MSG_INTL(MSG_SYM_INVSHNDX), 2328 demangle_symname(name, symsecname, ndx), 2329 ifl->ifl_name, 2330 conv_sym_shndx(osabi, mach, sym->st_shndx, 2331 CONV_FMT_DECIMAL, &inv_buf)); 2332 continue; 2333 } 2334 2335 isp = ifl->ifl_isdesc[shndx]; 2336 if (isp && (isp->is_flags & FLG_IS_DISCARD)) { 2337 if ((sdp = 2338 libld_calloc(sizeof (Sym_desc), 1)) == NULL) 2339 return (S_ERROR); 2340 2341 /* 2342 * Create a dummy symbol entry so that if we 2343 * find any references to this discarded symbol 2344 * we can compensate. 2345 */ 2346 sdp->sd_name = name; 2347 sdp->sd_sym = sym; 2348 sdp->sd_file = ifl; 2349 sdp->sd_isc = isp; 2350 sdp->sd_flags = FLG_SY_ISDISC; 2351 ifl->ifl_oldndx[ndx] = sdp; 2352 2353 DBG_CALL(Dbg_syms_discarded(ofl->ofl_lml, sdp)); 2354 continue; 2355 } 2356 } 2357 2358 /* 2359 * If the symbol does not already exist in the internal symbol 2360 * table add it, otherwise resolve the conflict. If the symbol 2361 * from this file is kept, retain its symbol table index for 2362 * possible use in associating a global alias. 2363 */ 2364 /* LINTED */ 2365 hash = (Word)elf_hash((const char *)name); 2366 if ((sdp = ld_sym_find(name, hash, &where, ofl)) == NULL) { 2367 DBG_CALL(Dbg_syms_global(ofl->ofl_lml, ndx, name)); 2368 if ((sdp = ld_sym_enter(name, sym, hash, ifl, ofl, ndx, 2369 shndx, sdflags, 0, &where)) == (Sym_desc *)S_ERROR) 2370 return (S_ERROR); 2371 2372 } else if (ld_sym_resolve(sdp, sym, ifl, ofl, ndx, shndx, 2373 sdflags) == S_ERROR) 2374 return (S_ERROR); 2375 2376 /* 2377 * After we've compared a defined symbol in one shared 2378 * object, flag the symbol so we don't compare it again. 2379 */ 2380 if ((etype == ET_DYN) && (sym->st_shndx != SHN_UNDEF) && 2381 ((sdp->sd_flags & FLG_SY_SOFOUND) == 0)) 2382 sdp->sd_flags |= FLG_SY_SOFOUND; 2383 2384 /* 2385 * If the symbol is accepted from this file retain the symbol 2386 * index for possible use in aliasing. 2387 */ 2388 if (sdp->sd_file == ifl) 2389 sdp->sd_symndx = ndx; 2390 2391 ifl->ifl_oldndx[ndx] = sdp; 2392 2393 /* 2394 * If we've accepted a register symbol, continue to validate 2395 * it. 2396 */ 2397 if (sdp->sd_flags & FLG_SY_REGSYM) { 2398 Sym_desc *rsdp; 2399 2400 /* 2401 * The presence of FLG_SY_REGSYM means that 2402 * the pointers in ld_targ.t_ms are non-NULL. 2403 */ 2404 rsdp = (*ld_targ.t_ms.ms_reg_find)(sdp->sd_sym, ofl); 2405 if (rsdp == NULL) { 2406 if ((*ld_targ.t_ms.ms_reg_enter)(sdp, ofl) == 0) 2407 return (S_ERROR); 2408 } else if (rsdp != sdp) { 2409 (void) (*ld_targ.t_ms.ms_reg_check)(rsdp, 2410 sdp->sd_sym, sdp->sd_name, ifl, ofl); 2411 } 2412 } 2413 2414 /* 2415 * For a relocatable object, if this symbol is defined 2416 * and has non-zero length and references an address 2417 * within an associated section, then check its extents 2418 * to make sure the section boundaries encompass it. 2419 * If they don't, the ELF file is corrupt. Note that this 2420 * global symbol may have come from another file to satisfy 2421 * an UNDEF symbol of the same name from this one. In that 2422 * case, we don't check it, because it was already checked 2423 * as part of its own file. 2424 */ 2425 if (etype_rel && (sdp->sd_file == ifl)) { 2426 Sym *tsym = sdp->sd_sym; 2427 2428 if (SYM_LOC_BADADDR(sdp, tsym, 2429 ELF_ST_TYPE(tsym->st_info))) { 2430 issue_badaddr_msg(ifl, ofl, sdp, 2431 tsym, tsym->st_shndx); 2432 continue; 2433 } 2434 } 2435 } 2436 2437 /* 2438 * Associate weak (alias) symbols to their non-weak counterparts by 2439 * scaning the global symbols one more time. 2440 * 2441 * This association is needed when processing the symbols from a shared 2442 * object dependency when a a weak definition satisfies a reference: 2443 * 2444 * - When building a dynamic executable, if a referenced symbol is a 2445 * data item, the symbol data is copied to the executables address 2446 * space. In this copy-relocation case, we must also reassociate 2447 * the alias symbol with its new location in the executable. 2448 * 2449 * - If the referenced symbol is a function then we may need to 2450 * promote the symbols binding from undefined weak to undefined, 2451 * otherwise the run-time linker will not generate the correct 2452 * relocation error should the symbol not be found. 2453 * 2454 * Weak alias association is also required when a local dynsym table 2455 * is being created. This table should only contain one instance of a 2456 * symbol that is associated to a given address. 2457 * 2458 * The true association between a weak/strong symbol pair is that both 2459 * symbol entries are identical, thus first we create a sorted symbol 2460 * list keyed off of the symbols section index and value. If the symbol 2461 * belongs to the same section and has the same value, then the chances 2462 * are that the rest of the symbols data is the same. This list is then 2463 * scanned for weak symbols, and if one is found then any strong 2464 * association will exist in the entries that follow. Thus we just have 2465 * to scan one (typically a single alias) or more (in the uncommon 2466 * instance of multiple weak to strong associations) entries to 2467 * determine if a match exists. 2468 */ 2469 if (weak && (OFL_ALLOW_LDYNSYM(ofl) || (etype == ET_DYN)) && 2470 (total > local)) { 2471 static Sym_desc **sort; 2472 static size_t osize = 0; 2473 size_t nsize = (total - local) * sizeof (Sym_desc *); 2474 2475 /* 2476 * As we might be processing many input files, and many symbols, 2477 * try and reuse a static sort buffer. Note, presently we're 2478 * playing the game of never freeing any buffers as there's a 2479 * belief this wastes time. 2480 */ 2481 if ((osize == 0) || (nsize > osize)) { 2482 if ((sort = libld_malloc(nsize)) == NULL) 2483 return (S_ERROR); 2484 osize = nsize; 2485 } 2486 (void) memcpy((void *)sort, &ifl->ifl_oldndx[local], nsize); 2487 2488 qsort(sort, (total - local), sizeof (Sym_desc *), compare); 2489 2490 for (ndx = 0; ndx < (total - local); ndx++) { 2491 Sym_desc *wsdp = sort[ndx]; 2492 Sym *wsym; 2493 int sndx; 2494 2495 /* 2496 * Ignore any empty symbol descriptor, or the case where 2497 * the symbol has been resolved to a different file. 2498 */ 2499 if ((wsdp == NULL) || (wsdp->sd_file != ifl)) 2500 continue; 2501 2502 wsym = wsdp->sd_sym; 2503 2504 if ((wsym->st_shndx == SHN_UNDEF) || 2505 (wsdp->sd_flags & FLG_SY_SPECSEC) || 2506 (ELF_ST_BIND(wsym->st_info) != STB_WEAK)) 2507 continue; 2508 2509 /* 2510 * We have a weak symbol, if it has a strong alias it 2511 * will have been sorted to one of the following sort 2512 * table entries. Note that we could have multiple weak 2513 * symbols aliased to one strong (if this occurs then 2514 * the strong symbol only maintains one alias back to 2515 * the last weak). 2516 */ 2517 for (sndx = ndx + 1; sndx < (total - local); sndx++) { 2518 Sym_desc *ssdp = sort[sndx]; 2519 Sym *ssym; 2520 int w_dynbits, s_dynbits; 2521 2522 /* 2523 * Ignore any empty symbol descriptor, or the 2524 * case where the symbol has been resolved to a 2525 * different file. 2526 */ 2527 if ((ssdp == NULL) || (ssdp->sd_file != ifl)) 2528 continue; 2529 2530 ssym = ssdp->sd_sym; 2531 2532 if (ssym->st_shndx == SHN_UNDEF) 2533 continue; 2534 2535 if ((ssym->st_shndx != wsym->st_shndx) || 2536 (ssym->st_value != wsym->st_value)) 2537 break; 2538 2539 if ((ssym->st_size != wsym->st_size) || 2540 (ssdp->sd_flags & FLG_SY_SPECSEC) || 2541 (ELF_ST_BIND(ssym->st_info) == STB_WEAK)) 2542 continue; 2543 2544 /* 2545 * If a sharable object, set link fields so 2546 * that they reference each other.` 2547 */ 2548 if (etype == ET_DYN) { 2549 ssdp->sd_aux->sa_linkndx = 2550 (Word)wsdp->sd_symndx; 2551 wsdp->sd_aux->sa_linkndx = 2552 (Word)ssdp->sd_symndx; 2553 } 2554 2555 /* 2556 * Determine which of these two symbols go into 2557 * the sort section. If a mapfile has made 2558 * explicit settings of the FLG_SY_*DYNSORT 2559 * flags for both symbols, then we do what they 2560 * say. If one has the DYNSORT flags set, we 2561 * set the NODYNSORT bit in the other. And if 2562 * neither has an explicit setting, then we 2563 * favor the weak symbol because they usually 2564 * lack the leading underscore. 2565 */ 2566 w_dynbits = wsdp->sd_flags & 2567 (FLG_SY_DYNSORT | FLG_SY_NODYNSORT); 2568 s_dynbits = ssdp->sd_flags & 2569 (FLG_SY_DYNSORT | FLG_SY_NODYNSORT); 2570 if (!(w_dynbits && s_dynbits)) { 2571 if (s_dynbits) { 2572 if (s_dynbits == FLG_SY_DYNSORT) 2573 wsdp->sd_flags |= 2574 FLG_SY_NODYNSORT; 2575 } else if (w_dynbits != 2576 FLG_SY_NODYNSORT) { 2577 ssdp->sd_flags |= 2578 FLG_SY_NODYNSORT; 2579 } 2580 } 2581 break; 2582 } 2583 } 2584 } 2585 return (1); 2586 2587 #undef SYM_LOC_BADADDR 2588 } 2589 2590 /* 2591 * Add an undefined symbol to the symbol table. The reference originates from 2592 * the location identifed by the message id (mid). These references can 2593 * originate from command line options such as -e, -u, -initarray, etc. 2594 * (identified with MSG_INTL(MSG_STR_COMMAND)), or from internally generated 2595 * TLS relocation references (identified with MSG_INTL(MSG_STR_TLSREL)). 2596 */ 2597 Sym_desc * 2598 ld_sym_add_u(const char *name, Ofl_desc *ofl, Msg mid) 2599 { 2600 Sym *sym; 2601 Ifl_desc *ifl = NULL, *_ifl; 2602 Sym_desc *sdp; 2603 Word hash; 2604 Aliste idx; 2605 avl_index_t where; 2606 const char *reference = MSG_INTL(mid); 2607 2608 /* 2609 * As an optimization, determine whether we've already generated this 2610 * reference. If the symbol doesn't already exist we'll create it. 2611 * Or if the symbol does exist from a different source, we'll resolve 2612 * the conflict. 2613 */ 2614 /* LINTED */ 2615 hash = (Word)elf_hash(name); 2616 if ((sdp = ld_sym_find(name, hash, &where, ofl)) != NULL) { 2617 if ((sdp->sd_sym->st_shndx == SHN_UNDEF) && 2618 (sdp->sd_file->ifl_name == reference)) 2619 return (sdp); 2620 } 2621 2622 /* 2623 * Determine whether a pseudo input file descriptor exists to represent 2624 * the command line, as any global symbol needs an input file descriptor 2625 * during any symbol resolution (refer to map_ifl() which provides a 2626 * similar method for adding symbols from mapfiles). 2627 */ 2628 for (APLIST_TRAVERSE(ofl->ofl_objs, idx, _ifl)) 2629 if (strcmp(_ifl->ifl_name, reference) == 0) { 2630 ifl = _ifl; 2631 break; 2632 } 2633 2634 /* 2635 * If no descriptor exists create one. 2636 */ 2637 if (ifl == NULL) { 2638 if ((ifl = libld_calloc(sizeof (Ifl_desc), 1)) == NULL) 2639 return ((Sym_desc *)S_ERROR); 2640 ifl->ifl_name = reference; 2641 ifl->ifl_flags = FLG_IF_NEEDED | FLG_IF_FILEREF; 2642 if ((ifl->ifl_ehdr = libld_calloc(sizeof (Ehdr), 1)) == NULL) 2643 return ((Sym_desc *)S_ERROR); 2644 ifl->ifl_ehdr->e_type = ET_REL; 2645 2646 if (aplist_append(&ofl->ofl_objs, ifl, AL_CNT_OFL_OBJS) == NULL) 2647 return ((Sym_desc *)S_ERROR); 2648 } 2649 2650 /* 2651 * Allocate a symbol structure and add it to the global symbol table. 2652 */ 2653 if ((sym = libld_calloc(sizeof (Sym), 1)) == NULL) 2654 return ((Sym_desc *)S_ERROR); 2655 sym->st_info = ELF_ST_INFO(STB_GLOBAL, STT_NOTYPE); 2656 sym->st_shndx = SHN_UNDEF; 2657 2658 DBG_CALL(Dbg_syms_process(ofl->ofl_lml, ifl)); 2659 if (sdp == NULL) { 2660 DBG_CALL(Dbg_syms_global(ofl->ofl_lml, 0, name)); 2661 if ((sdp = ld_sym_enter(name, sym, hash, ifl, ofl, 0, SHN_UNDEF, 2662 0, 0, &where)) == (Sym_desc *)S_ERROR) 2663 return ((Sym_desc *)S_ERROR); 2664 } else if (ld_sym_resolve(sdp, sym, ifl, ofl, 0, 2665 SHN_UNDEF, 0) == S_ERROR) 2666 return ((Sym_desc *)S_ERROR); 2667 2668 sdp->sd_flags &= ~FLG_SY_CLEAN; 2669 sdp->sd_flags |= FLG_SY_CMDREF; 2670 2671 return (sdp); 2672 } 2673 2674 /* 2675 * STT_SECTION symbols have their st_name field set to NULL, and consequently 2676 * have no name. Generate a name suitable for diagnostic use for such a symbol. 2677 * The resulting name will be of the form: 2678 * 2679 * "XXX (section)" 2680 * 2681 * where XXX is the name of the section. 2682 * 2683 * Diagnostics for STT_SECTION symbols tend to come in clusters, 2684 * so we use a static variable to retain the last string we generate. If 2685 * another one comes along for the same section before some other section 2686 * intervenes, we will reuse the string. 2687 * 2688 * entry: 2689 * isc - Input section assocated with the symbol. 2690 * fmt - NULL, or format string to use. 2691 * 2692 * exit: 2693 * Returns the allocated string, or NULL on allocation failure. 2694 */ 2695 const const char * 2696 ld_stt_section_sym_name(Is_desc *isp) 2697 { 2698 static const char *last_fmt; 2699 static Is_desc *last_isp = NULL; 2700 static char *namestr; 2701 2702 const char *fmt; 2703 size_t len; 2704 2705 if ((isp != NULL) && (isp->is_name != NULL)) { 2706 fmt = (isp->is_flags & FLG_IS_GNSTRMRG) ? 2707 MSG_INTL(MSG_STR_SECTION_MSTR) : MSG_INTL(MSG_STR_SECTION); 2708 2709 if ((last_isp == isp) && (last_fmt == fmt)) 2710 return (namestr); 2711 2712 len = strlen(fmt) + strlen(isp->is_name) + 1; 2713 2714 if ((namestr = libld_malloc(len)) == 0) 2715 return (NULL); 2716 (void) snprintf(namestr, len, fmt, isp->is_name); 2717 2718 /* Remember for next time */ 2719 last_fmt = fmt; 2720 last_isp = isp; 2721 2722 return (namestr); 2723 } 2724 2725 return (NULL); 2726 } 2727