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 (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved. 28 */ 29 30 /* 31 * Symbol table management routines 32 */ 33 34 #define ELF_TARGET_AMD64 35 36 #include <stdio.h> 37 #include <string.h> 38 #include <debug.h> 39 #include <alloca.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, sd_flag_t *flags) 81 { 82 Word name = sym->st_name; 83 84 if (name) { 85 if ((ifl->ifl_flags & FLG_IF_HSTRTAB) == 0) { 86 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_FIL_NOSTRTABLE), 87 ifl->ifl_name, EC_WORD(symsecndx), symsecname, 88 symndx, EC_XWORD(name)); 89 return (NULL); 90 } 91 if (name >= (Word)strsize) { 92 ld_eprintf(ofl, ERR_FATAL, 93 MSG_INTL(MSG_FIL_EXCSTRTABLE), ifl->ifl_name, 94 EC_WORD(symsecndx), symsecname, symndx, 95 EC_XWORD(name), strsecname, EC_XWORD(strsize)); 96 return (NULL); 97 } 98 } 99 100 /* 101 * Determine if we're dealing with a register and if so validate it. 102 * If it's a scratch register, a fabricated name will be returned. 103 */ 104 if (ld_targ.t_ms.ms_is_regsym != NULL) { 105 const char *regname = (*ld_targ.t_ms.ms_is_regsym)(ofl, ifl, 106 sym, strs, symndx, shndx, symsecname, flags); 107 108 if (regname == (const char *)S_ERROR) { 109 return (NULL); 110 } 111 if (regname) 112 return (regname); 113 } 114 115 /* 116 * If this isn't a register, but we have a global symbol with a null 117 * name, we're not going to be able to hash this, search for it, or 118 * do anything interesting. However, we've been accepting a symbol of 119 * this kind for ages now, so give the user a warning (rather than a 120 * fatal error), just in case this instance exists somewhere in the 121 * world and hasn't, as yet, been a problem. 122 */ 123 if ((name == 0) && (ELF_ST_BIND(sym->st_info) != STB_LOCAL)) { 124 ld_eprintf(ofl, ERR_WARNING, MSG_INTL(MSG_FIL_NONAMESYM), 125 ifl->ifl_name, EC_WORD(symsecndx), symsecname, symndx, 126 EC_XWORD(name)); 127 } 128 return (strs + name); 129 } 130 131 /* 132 * For producing symbol names strings to use in error messages. 133 * If the symbol has a non-null name, then the string returned by 134 * this function is the output from demangle(), surrounded by 135 * single quotes. For null names, a descriptive string giving 136 * the symbol section and index is generated. 137 * 138 * This function uses an internal static buffer to hold the resulting 139 * string. The value returned is usable by the caller until the next 140 * call, at which point it is overwritten. 141 */ 142 static const char * 143 demangle_symname(const char *name, const char *symtab_name, Word symndx) 144 { 145 #define INIT_BUFSIZE 256 146 147 static char *buf; 148 static size_t bufsize = 0; 149 size_t len; 150 int use_name; 151 152 use_name = (name != NULL) && (*name != '\0'); 153 154 if (use_name) { 155 name = demangle(name); 156 len = strlen(name) + 2; /* Include room for quotes */ 157 } else { 158 name = MSG_ORIG(MSG_STR_EMPTY); 159 len = strlen(symtab_name) + 2 + CONV_INV_BUFSIZE; 160 } 161 len++; /* Null termination */ 162 163 /* If our buffer is too small, double it until it is big enough */ 164 if (len > bufsize) { 165 size_t new_bufsize = bufsize; 166 char *new_buf; 167 168 if (new_bufsize == 0) 169 new_bufsize = INIT_BUFSIZE; 170 while (len > new_bufsize) 171 new_bufsize *= 2; 172 if ((new_buf = libld_malloc(new_bufsize)) == NULL) 173 return (name); 174 buf = new_buf; 175 bufsize = new_bufsize; 176 } 177 178 if (use_name) { 179 (void) snprintf(buf, bufsize, MSG_ORIG(MSG_FMT_SYMNAM), name); 180 } else { 181 (void) snprintf(buf, bufsize, MSG_ORIG(MSG_FMT_NULLSYMNAM), 182 symtab_name, EC_WORD(symndx)); 183 } 184 185 return (buf); 186 187 #undef INIT_BUFSIZE 188 } 189 190 /* 191 * Shared objects can be built that define specific symbols that can not be 192 * directly bound to. These objects have a syminfo section (and an associated 193 * DF_1_NODIRECT dynamic flags entry). Scan this table looking for symbols 194 * that can't be bound to directly, and if this files symbol is presently 195 * referenced, mark it so that we don't directly bind to it. 196 */ 197 uintptr_t 198 ld_sym_nodirect(Is_desc *isp, Ifl_desc *ifl, Ofl_desc *ofl) 199 { 200 Shdr *sifshdr, *symshdr; 201 Syminfo *sifdata; 202 Sym *symdata; 203 char *strdata; 204 ulong_t cnt, _cnt; 205 206 /* 207 * Get the syminfo data, and determine the number of entries. 208 */ 209 sifshdr = isp->is_shdr; 210 sifdata = (Syminfo *)isp->is_indata->d_buf; 211 cnt = sifshdr->sh_size / sifshdr->sh_entsize; 212 213 /* 214 * Get the associated symbol table. 215 */ 216 if ((sifshdr->sh_link == 0) || (sifshdr->sh_link >= ifl->ifl_shnum)) { 217 /* 218 * Broken input file 219 */ 220 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_FIL_INVSHINFO), 221 ifl->ifl_name, isp->is_name, EC_XWORD(sifshdr->sh_link)); 222 return (0); 223 } 224 symshdr = ifl->ifl_isdesc[sifshdr->sh_link]->is_shdr; 225 symdata = ifl->ifl_isdesc[sifshdr->sh_link]->is_indata->d_buf; 226 227 /* 228 * Get the string table associated with the symbol table. 229 */ 230 strdata = ifl->ifl_isdesc[symshdr->sh_link]->is_indata->d_buf; 231 232 /* 233 * Traverse the syminfo data for symbols that can't be directly 234 * bound to. 235 */ 236 for (_cnt = 1, sifdata++; _cnt < cnt; _cnt++, sifdata++) { 237 Sym *sym; 238 char *str; 239 Sym_desc *sdp; 240 241 if ((sifdata->si_flags & SYMINFO_FLG_NOEXTDIRECT) == 0) 242 continue; 243 244 sym = (Sym *)(symdata + _cnt); 245 str = (char *)(strdata + sym->st_name); 246 247 if ((sdp = ld_sym_find(str, SYM_NOHASH, NULL, ofl)) != NULL) { 248 if (ifl != sdp->sd_file) 249 continue; 250 251 sdp->sd_flags &= ~FLG_SY_DIR; 252 sdp->sd_flags |= FLG_SY_NDIR; 253 } 254 } 255 return (0); 256 } 257 258 /* 259 * If, during symbol processing, it is necessary to update a local symbols 260 * contents before we have generated the symbol tables in the output image, 261 * create a new symbol structure and copy the original symbol contents. While 262 * we are processing the input files, their local symbols are part of the 263 * read-only mapped image. Commonly, these symbols are copied to the new output 264 * file image and then updated to reflect their new address and any change in 265 * attributes. However, sometimes during relocation counting, it is necessary 266 * to adjust the symbols information. This routine provides for the generation 267 * of a new symbol image so that this update can be performed. 268 * All global symbols are copied to an internal symbol table to improve locality 269 * of reference and hence performance, and thus this copying is not necessary. 270 */ 271 uintptr_t 272 ld_sym_copy(Sym_desc *sdp) 273 { 274 Sym *nsym; 275 276 if (sdp->sd_flags & FLG_SY_CLEAN) { 277 if ((nsym = libld_malloc(sizeof (Sym))) == NULL) 278 return (S_ERROR); 279 *nsym = *(sdp->sd_sym); 280 sdp->sd_sym = nsym; 281 sdp->sd_flags &= ~FLG_SY_CLEAN; 282 } 283 return (1); 284 } 285 286 /* 287 * Finds a given name in the link editors internal symbol table. If no 288 * hash value is specified it is calculated. A pointer to the located 289 * Sym_desc entry is returned, or NULL if the symbol is not found. 290 */ 291 Sym_desc * 292 ld_sym_find(const char *name, Word hash, avl_index_t *where, Ofl_desc *ofl) 293 { 294 Sym_avlnode qsav, *sav; 295 296 if (hash == SYM_NOHASH) 297 /* LINTED */ 298 hash = (Word)elf_hash((const char *)name); 299 qsav.sav_hash = hash; 300 qsav.sav_name = name; 301 302 /* 303 * Perform search for symbol in AVL tree. Note that the 'where' field 304 * is passed in from the caller. If a 'where' is present, it can be 305 * used in subsequent 'ld_sym_enter()' calls if required. 306 */ 307 sav = avl_find(&ofl->ofl_symavl, &qsav, where); 308 309 /* 310 * If symbol was not found in the avl tree, return null to show that. 311 */ 312 if (sav == NULL) 313 return (NULL); 314 315 /* 316 * Return symbol found. 317 */ 318 return (sav->sav_sdp); 319 } 320 321 /* 322 * Enter a new symbol into the link editors internal symbol table. 323 * If the symbol is from an input file, information regarding the input file 324 * and input section is also recorded. Otherwise (file == NULL) the symbol 325 * has been internally generated (ie. _etext, _edata, etc.). 326 */ 327 Sym_desc * 328 ld_sym_enter(const char *name, Sym *osym, Word hash, Ifl_desc *ifl, 329 Ofl_desc *ofl, Word ndx, Word shndx, sd_flag_t sdflags, 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(S_DROUND(sizeof (Sym_avlnode)) + 355 S_DROUND(sizeof (Sym_desc)) + 356 S_DROUND(sizeof (Sym_aux)), 1)) == NULL) 357 return ((Sym_desc *)S_ERROR); 358 sdp = (Sym_desc *)((uintptr_t)savl + 359 S_DROUND(sizeof (Sym_avlnode))); 360 sap = (Sym_aux *)((uintptr_t)sdp + 361 S_DROUND(sizeof (Sym_desc))); 362 363 savl->sav_sdp = sdp; 364 sdp->sd_file = ifl; 365 sdp->sd_aux = sap; 366 savl->sav_hash = sap->sa_hash = hash; 367 368 /* 369 * Copy the symbol table entry from the input file into the internal 370 * entry and have the symbol descriptor use it. 371 */ 372 sdp->sd_sym = nsym = &sap->sa_sym; 373 *nsym = *osym; 374 sdp->sd_shndx = shndx; 375 sdp->sd_flags |= sdflags; 376 377 if ((_name = libld_malloc(strlen(name) + 1)) == NULL) 378 return ((Sym_desc *)S_ERROR); 379 savl->sav_name = sdp->sd_name = (const char *)strcpy(_name, name); 380 381 /* 382 * Enter Symbol in AVL tree. 383 */ 384 if (where == 0) { 385 /* LINTED */ 386 Sym_avlnode *_savl; 387 /* 388 * If a previous ld_sym_find() hasn't initialized 'where' do it 389 * now. 390 */ 391 where = &_where; 392 _savl = avl_find(&ofl->ofl_symavl, savl, where); 393 assert(_savl == NULL); 394 } 395 avl_insert(&ofl->ofl_symavl, savl, *where); 396 397 /* 398 * Record the section index. This is possible because the 399 * `ifl_isdesc' table is filled before we start symbol processing. 400 */ 401 if ((sdflags & FLG_SY_SPECSEC) || (nsym->st_shndx == SHN_UNDEF)) 402 sdp->sd_isc = NULL; 403 else { 404 sdp->sd_isc = ifl->ifl_isdesc[shndx]; 405 406 /* 407 * If this symbol is from a relocatable object, make sure that 408 * it is still associated with a section. For example, an 409 * unknown section type (SHT_NULL) would have been rejected on 410 * input with a warning. Here, we make the use of the symbol 411 * fatal. A symbol descriptor is still returned, so that the 412 * caller can continue processing all symbols, and hence flush 413 * out as many error conditions as possible. 414 */ 415 if ((etype == ET_REL) && (sdp->sd_isc == NULL)) { 416 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_SYM_INVSEC), 417 name, ifl->ifl_name, EC_XWORD(shndx)); 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_flags |= FLG_SY_DEFAULT; 444 break; 445 case STV_INTERNAL: 446 case STV_HIDDEN: 447 sdp->sd_flags |= FLG_SY_HIDDEN; 448 break; 449 case STV_PROTECTED: 450 sdp->sd_flags |= FLG_SY_PROTECT; 451 break; 452 case STV_EXPORTED: 453 sdp->sd_flags |= FLG_SY_EXPORT; 454 break; 455 case STV_SINGLETON: 456 sdp->sd_flags |= (FLG_SY_SINGLE | FLG_SY_NDIR); 457 ofl->ofl_flags1 |= (FLG_OF1_NDIRECT | FLG_OF1_NGLBDIR); 458 break; 459 case STV_ELIMINATE: 460 sdp->sd_flags |= (FLG_SY_HIDDEN | FLG_SY_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_flags & (FLG_SY_PROTECT | FLG_SY_DIR)) == 0) && 475 (nsym->st_shndx != SHN_UNDEF)) { 476 sdp->sd_flags |= FLG_SY_NDIR; 477 } 478 } else { 479 sdp->sd_ref = REF_DYN_SEEN; 480 481 /* 482 * If this is a protected symbol, remember this. Note, this 483 * state is different from the FLG_SY_PROTECT used to establish 484 * a symbol definitions visibility. This state is used to warn 485 * against possible copy relocations against this referenced 486 * symbol. 487 */ 488 if (vis == STV_PROTECTED) 489 sdp->sd_flags |= FLG_SY_PROT; 490 491 /* 492 * If this is a SINGLETON definition, then indicate the symbol 493 * can not be directly bound to, and retain the visibility. 494 * This visibility will be inherited by any references made to 495 * this symbol. 496 */ 497 if ((vis == STV_SINGLETON) && (nsym->st_shndx != SHN_UNDEF)) 498 sdp->sd_flags |= (FLG_SY_SINGLE | FLG_SY_NDIR); 499 500 /* 501 * If the new symbol is from a shared library and is associated 502 * with a SHT_NOBITS section then this symbol originated from a 503 * tentative symbol. 504 */ 505 if (sdp->sd_isc && 506 (sdp->sd_isc->is_shdr->sh_type == SHT_NOBITS)) 507 sdp->sd_flags |= FLG_SY_TENTSYM; 508 } 509 510 /* 511 * Reclassify any SHN_SUNW_IGNORE symbols to SHN_UNDEF so as to 512 * simplify future processing. 513 */ 514 if (nsym->st_shndx == SHN_SUNW_IGNORE) { 515 sdp->sd_shndx = shndx = SHN_UNDEF; 516 sdp->sd_flags |= (FLG_SY_REDUCED | 517 FLG_SY_HIDDEN | FLG_SY_IGNORE | FLG_SY_ELIM); 518 } 519 520 /* 521 * If this is an undefined, or common symbol from a relocatable object 522 * determine whether it is a global or weak reference (see build_osym(), 523 * where REF_DYN_NEED definitions are returned back to undefines). 524 */ 525 if ((etype == ET_REL) && 526 (ELF_ST_BIND(nsym->st_info) == STB_GLOBAL) && 527 ((nsym->st_shndx == SHN_UNDEF) || ((sdflags & FLG_SY_SPECSEC) && 528 #if defined(_ELF64) 529 ((nsym->st_shndx == SHN_COMMON) || 530 ((ld_targ.t_m.m_mach == EM_AMD64) && 531 (nsym->st_shndx == SHN_X86_64_LCOMMON)))))) 532 #else 533 /* BEGIN CSTYLED */ 534 (nsym->st_shndx == SHN_COMMON)))) 535 /* END CSTYLED */ 536 #endif 537 sdp->sd_flags |= FLG_SY_GLOBREF; 538 539 /* 540 * Record the input filename on the referenced or defined files list 541 * for possible later diagnostics. The `sa_rfile' pointer contains the 542 * name of the file that first referenced this symbol and is used to 543 * generate undefined symbol diagnostics (refer to sym_undef_entry()). 544 * Note that this entry can be overridden if a reference from a 545 * relocatable object is found after a reference from a shared object 546 * (refer to sym_override()). 547 * The `sa_dfiles' list is used to maintain the list of files that 548 * define the same symbol. This list can be used for two reasons: 549 * 550 * - To save the first definition of a symbol that is not available 551 * for this link-edit. 552 * 553 * - To save all definitions of a symbol when the -m option is in 554 * effect. This is optional as it is used to list multiple 555 * (interposed) definitions of a symbol (refer to ldmap_out()), 556 * and can be quite expensive. 557 */ 558 if (nsym->st_shndx == SHN_UNDEF) { 559 sap->sa_rfile = ifl->ifl_name; 560 } else { 561 if (sdp->sd_ref == REF_DYN_SEEN) { 562 /* 563 * A symbol is determined to be unavailable if it 564 * belongs to a version of a shared object that this 565 * user does not wish to use, or if it belongs to an 566 * implicit shared object. 567 */ 568 if (ifl->ifl_vercnt) { 569 Ver_index *vip; 570 Half vndx = ifl->ifl_versym[ndx]; 571 572 sap->sa_dverndx = vndx; 573 vip = &ifl->ifl_verndx[vndx]; 574 if (!(vip->vi_flags & FLG_VER_AVAIL)) { 575 sdp->sd_flags |= FLG_SY_NOTAVAIL; 576 sap->sa_vfile = ifl->ifl_name; 577 } 578 } 579 if (!(ifl->ifl_flags & FLG_IF_NEEDED)) 580 sdp->sd_flags |= FLG_SY_NOTAVAIL; 581 582 } else if (etype == ET_REL) { 583 /* 584 * If this symbol has been obtained from a versioned 585 * input relocatable object then the new symbol must be 586 * promoted to the versioning of the output file. 587 */ 588 if (ifl->ifl_versym) 589 ld_vers_promote(sdp, ndx, ifl, ofl); 590 } 591 592 if ((ofl->ofl_flags & FLG_OF_GENMAP) && 593 ((sdflags & FLG_SY_SPECSEC) == 0)) 594 if (aplist_append(&sap->sa_dfiles, ifl->ifl_name, 595 AL_CNT_SDP_DFILES) == NULL) 596 return ((Sym_desc *)S_ERROR); 597 } 598 599 /* 600 * Provided we're not processing a mapfile, diagnose the entered symbol. 601 * Mapfile processing requires the symbol to be updated with additional 602 * information, therefore the diagnosing of the symbol is deferred until 603 * later (see Dbg_map_symbol()). 604 */ 605 if ((ifl == NULL) || ((ifl->ifl_flags & FLG_IF_MAPFILE) == 0)) 606 DBG_CALL(Dbg_syms_entered(ofl, nsym, sdp)); 607 608 return (sdp); 609 } 610 611 /* 612 * Add a special symbol to the symbol table. Takes special symbol name with 613 * and without underscores. This routine is called, after all other symbol 614 * resolution has completed, to generate a reserved absolute symbol (the 615 * underscore version). Special symbols are updated with the appropriate 616 * values in update_osym(). If the user has already defined this symbol 617 * issue a warning and leave the symbol as is. If the non-underscore symbol 618 * is referenced then turn it into a weak alias of the underscored symbol. 619 * 620 * The bits in sdflags_u are OR'd into the flags field of the symbol for the 621 * underscored symbol. 622 * 623 * If this is a global symbol, and it hasn't explicitly been defined as being 624 * directly bound to, indicate that it can't be directly bound to. 625 * Historically, most special symbols only have meaning to the object in which 626 * they exist, however, they've always been global. To ensure compatibility 627 * with any unexpected use presently in effect, ensure these symbols don't get 628 * directly bound to. Note, that establishing this state here isn't sufficient 629 * to create a syminfo table, only if a syminfo table is being created by some 630 * other symbol directives will the nodirect binding be recorded. This ensures 631 * we don't create syminfo sections for all objects we create, as this might add 632 * unnecessary bloat to users who haven't explicitly requested extra symbol 633 * information. 634 */ 635 static uintptr_t 636 sym_add_spec(const char *name, const char *uname, Word sdaux_id, 637 sd_flag_t sdflags_u, sd_flag_t sdflags, Ofl_desc *ofl) 638 { 639 Sym_desc *sdp; 640 Sym_desc *usdp; 641 Sym *sym; 642 Word hash; 643 avl_index_t where; 644 645 /* LINTED */ 646 hash = (Word)elf_hash(uname); 647 if (usdp = ld_sym_find(uname, hash, &where, ofl)) { 648 /* 649 * If the underscore symbol exists and is undefined, or was 650 * defined in a shared library, convert it to a local symbol. 651 * Otherwise leave it as is and warn the user. 652 */ 653 if ((usdp->sd_shndx == SHN_UNDEF) || 654 (usdp->sd_ref != REF_REL_NEED)) { 655 usdp->sd_ref = REF_REL_NEED; 656 usdp->sd_shndx = usdp->sd_sym->st_shndx = SHN_ABS; 657 usdp->sd_flags |= FLG_SY_SPECSEC | sdflags_u; 658 usdp->sd_sym->st_info = 659 ELF_ST_INFO(STB_GLOBAL, STT_OBJECT); 660 usdp->sd_isc = NULL; 661 usdp->sd_sym->st_size = 0; 662 usdp->sd_sym->st_value = 0; 663 /* LINTED */ 664 usdp->sd_aux->sa_symspec = (Half)sdaux_id; 665 666 /* 667 * If a user hasn't specifically indicated that the 668 * scope of this symbol be made local, then leave it 669 * as global (ie. prevent automatic scoping). The GOT 670 * should be defined protected, whereas all other 671 * special symbols are tagged as no-direct. 672 */ 673 if (!SYM_IS_HIDDEN(usdp) && 674 (sdflags & FLG_SY_DEFAULT)) { 675 usdp->sd_aux->sa_overndx = VER_NDX_GLOBAL; 676 if (sdaux_id == SDAUX_ID_GOT) { 677 usdp->sd_flags &= ~FLG_SY_NDIR; 678 usdp->sd_flags |= FLG_SY_PROTECT; 679 usdp->sd_sym->st_other = STV_PROTECTED; 680 } else if ( 681 ((usdp->sd_flags & FLG_SY_DIR) == 0) && 682 ((ofl->ofl_flags & FLG_OF_SYMBOLIC) == 0)) { 683 usdp->sd_flags |= FLG_SY_NDIR; 684 } 685 } 686 usdp->sd_flags |= sdflags; 687 688 /* 689 * If the reference originated from a mapfile ensure 690 * we mark the symbol as used. 691 */ 692 if (usdp->sd_flags & FLG_SY_MAPREF) 693 usdp->sd_flags |= FLG_SY_MAPUSED; 694 695 DBG_CALL(Dbg_syms_updated(ofl, usdp, uname)); 696 } else { 697 ld_eprintf(ofl, ERR_WARNING, MSG_INTL(MSG_SYM_RESERVE), 698 uname, usdp->sd_file->ifl_name); 699 } 700 } else { 701 /* 702 * If the symbol does not exist create it. 703 */ 704 if ((sym = libld_calloc(sizeof (Sym), 1)) == NULL) 705 return (S_ERROR); 706 sym->st_shndx = SHN_ABS; 707 sym->st_info = ELF_ST_INFO(STB_GLOBAL, STT_OBJECT); 708 sym->st_size = 0; 709 sym->st_value = 0; 710 DBG_CALL(Dbg_syms_created(ofl->ofl_lml, uname)); 711 if ((usdp = ld_sym_enter(uname, sym, hash, (Ifl_desc *)NULL, 712 ofl, 0, SHN_ABS, (FLG_SY_SPECSEC | sdflags_u), &where)) == 713 (Sym_desc *)S_ERROR) 714 return (S_ERROR); 715 usdp->sd_ref = REF_REL_NEED; 716 /* LINTED */ 717 usdp->sd_aux->sa_symspec = (Half)sdaux_id; 718 719 usdp->sd_aux->sa_overndx = VER_NDX_GLOBAL; 720 721 if (sdaux_id == SDAUX_ID_GOT) { 722 usdp->sd_flags |= FLG_SY_PROTECT; 723 usdp->sd_sym->st_other = STV_PROTECTED; 724 } else if ((sdflags & FLG_SY_DEFAULT) && 725 ((ofl->ofl_flags & FLG_OF_SYMBOLIC) == 0)) { 726 usdp->sd_flags |= FLG_SY_NDIR; 727 } 728 usdp->sd_flags |= sdflags; 729 } 730 731 if (name && (sdp = ld_sym_find(name, SYM_NOHASH, NULL, ofl)) && 732 (sdp->sd_sym->st_shndx == SHN_UNDEF)) { 733 uchar_t bind; 734 735 /* 736 * If the non-underscore symbol exists and is undefined 737 * convert it to be a local. If the underscore has 738 * sa_symspec set (ie. it was created above) then simulate this 739 * as a weak alias. 740 */ 741 sdp->sd_ref = REF_REL_NEED; 742 sdp->sd_shndx = sdp->sd_sym->st_shndx = SHN_ABS; 743 sdp->sd_flags |= FLG_SY_SPECSEC; 744 sdp->sd_isc = NULL; 745 sdp->sd_sym->st_size = 0; 746 sdp->sd_sym->st_value = 0; 747 /* LINTED */ 748 sdp->sd_aux->sa_symspec = (Half)sdaux_id; 749 if (usdp->sd_aux->sa_symspec) { 750 usdp->sd_aux->sa_linkndx = 0; 751 sdp->sd_aux->sa_linkndx = 0; 752 bind = STB_WEAK; 753 } else 754 bind = STB_GLOBAL; 755 sdp->sd_sym->st_info = ELF_ST_INFO(bind, STT_OBJECT); 756 757 /* 758 * If a user hasn't specifically indicated the scope of this 759 * symbol be made local then leave it as global (ie. prevent 760 * automatic scoping). The GOT should be defined protected, 761 * whereas all other special symbols are tagged as no-direct. 762 */ 763 if (!SYM_IS_HIDDEN(sdp) && 764 (sdflags & FLG_SY_DEFAULT)) { 765 sdp->sd_aux->sa_overndx = VER_NDX_GLOBAL; 766 if (sdaux_id == SDAUX_ID_GOT) { 767 sdp->sd_flags &= ~FLG_SY_NDIR; 768 sdp->sd_flags |= FLG_SY_PROTECT; 769 sdp->sd_sym->st_other = STV_PROTECTED; 770 } else if (((sdp->sd_flags & FLG_SY_DIR) == 0) && 771 ((ofl->ofl_flags & FLG_OF_SYMBOLIC) == 0)) { 772 sdp->sd_flags |= FLG_SY_NDIR; 773 } 774 } 775 sdp->sd_flags |= sdflags; 776 777 /* 778 * If the reference originated from a mapfile ensure 779 * we mark the symbol as used. 780 */ 781 if (sdp->sd_flags & FLG_SY_MAPREF) 782 sdp->sd_flags |= FLG_SY_MAPUSED; 783 784 DBG_CALL(Dbg_syms_updated(ofl, sdp, name)); 785 } 786 return (1); 787 } 788 789 790 /* 791 * Undefined symbols can fall into one of four types: 792 * 793 * - the symbol is really undefined (SHN_UNDEF). 794 * 795 * - versioning has been enabled, however this symbol has not been assigned 796 * to one of the defined versions. 797 * 798 * - the symbol has been defined by an implicitly supplied library, ie. one 799 * which was encounted because it was NEEDED by another library, rather 800 * than from a command line supplied library which would become the only 801 * dependency of the output file being produced. 802 * 803 * - the symbol has been defined by a version of a shared object that is 804 * not permitted for this link-edit. 805 * 806 * In all cases the file who made the first reference to this symbol will have 807 * been recorded via the `sa_rfile' pointer. 808 */ 809 typedef enum { 810 UNDEF, NOVERSION, IMPLICIT, NOTAVAIL, 811 BNDLOCAL 812 } Type; 813 814 static const Msg format[] = { 815 MSG_SYM_UND_UNDEF, /* MSG_INTL(MSG_SYM_UND_UNDEF) */ 816 MSG_SYM_UND_NOVER, /* MSG_INTL(MSG_SYM_UND_NOVER) */ 817 MSG_SYM_UND_IMPL, /* MSG_INTL(MSG_SYM_UND_IMPL) */ 818 MSG_SYM_UND_NOTA, /* MSG_INTL(MSG_SYM_UND_NOTA) */ 819 MSG_SYM_UND_BNDLOCAL /* MSG_INTL(MSG_SYM_UND_BNDLOCAL) */ 820 }; 821 822 /* 823 * Issue an undefined symbol message for the given symbol. 824 * 825 * entry: 826 * ofl - Output descriptor 827 * sdp - Undefined symbol to report 828 * type - Type of undefined symbol 829 * ofl_flag - One of 0, FLG_OF_FATAL, or FLG_OF_WARN. 830 * undef_state - Address of variable to be initialized to 0 831 * before the first call to sym_undef_entry, and passed 832 * to each subsequent call. A non-zero value for *undef_state 833 * indicates that this is not the first call in the series. 834 * 835 * exit: 836 * If *undef_state is 0, a title is issued. 837 * 838 * A message for the undefined symbol is issued. 839 * 840 * If ofl_flag is non-zero, its value is OR'd into *undef_state. Otherwise, 841 * all bits other than FLG_OF_FATAL and FLG_OF_WARN are set, in order to 842 * provide *undef_state with a non-zero value. These other bits have 843 * no meaning beyond that, and serve to ensure that *undef_state is 844 * non-zero if sym_undef_entry() has been called. 845 */ 846 static void 847 sym_undef_entry(Ofl_desc *ofl, Sym_desc *sdp, Type type, ofl_flag_t ofl_flag, 848 ofl_flag_t *undef_state) 849 { 850 const char *name1, *name2, *name3; 851 Ifl_desc *ifl = sdp->sd_file; 852 Sym_aux *sap = sdp->sd_aux; 853 854 if (*undef_state == 0) 855 ld_eprintf(ofl, ERR_NONE, MSG_INTL(MSG_SYM_FMT_UNDEF), 856 MSG_INTL(MSG_SYM_UNDEF_ITM_11), 857 MSG_INTL(MSG_SYM_UNDEF_ITM_21), 858 MSG_INTL(MSG_SYM_UNDEF_ITM_12), 859 MSG_INTL(MSG_SYM_UNDEF_ITM_22)); 860 861 ofl->ofl_flags |= ofl_flag; 862 *undef_state |= ofl_flag ? ofl_flag : ~(FLG_OF_FATAL | FLG_OF_WARN); 863 864 switch (type) { 865 case UNDEF: 866 case BNDLOCAL: 867 name1 = sap->sa_rfile; 868 break; 869 case NOVERSION: 870 name1 = ifl->ifl_name; 871 break; 872 case IMPLICIT: 873 name1 = sap->sa_rfile; 874 name2 = ifl->ifl_name; 875 break; 876 case NOTAVAIL: 877 name1 = sap->sa_rfile; 878 name2 = sap->sa_vfile; 879 name3 = ifl->ifl_verndx[sap->sa_dverndx].vi_name; 880 break; 881 default: 882 return; 883 } 884 885 ld_eprintf(ofl, ERR_NONE, MSG_INTL(format[type]), 886 demangle(sdp->sd_name), name1, name2, name3); 887 } 888 889 /* 890 * If an undef symbol exists naming a bound for the output section, 891 * turn it into a defined symbol with the correct value. 892 * 893 * We set an arbitrary 1KB limit on the resulting symbol names. 894 */ 895 static void 896 sym_add_bounds(Ofl_desc *ofl, Os_desc *osp, Word bound) 897 { 898 Sym_desc *bsdp; 899 char symn[1024]; 900 size_t nsz; 901 902 switch (bound) { 903 case SDAUX_ID_SECBOUND_START: 904 nsz = snprintf(symn, sizeof (symn), "%s%s", 905 MSG_ORIG(MSG_SYM_SECBOUND_START), osp->os_name + 1); 906 if (nsz > sizeof (symn)) 907 return; 908 break; 909 case SDAUX_ID_SECBOUND_STOP: 910 nsz = snprintf(symn, sizeof (symn), "%s%s", 911 MSG_ORIG(MSG_SYM_SECBOUND_STOP), osp->os_name + 1); 912 if (nsz > sizeof (symn)) 913 return; 914 break; 915 default: 916 assert(0); 917 } 918 919 if ((bsdp = ld_sym_find(symn, SYM_NOHASH, NULL, ofl)) != NULL) { 920 if ((bsdp->sd_shndx != SHN_UNDEF) && 921 (bsdp->sd_ref == REF_REL_NEED)) { 922 ld_eprintf(ofl, ERR_WARNING, MSG_INTL(MSG_SYM_RESERVE), 923 symn, bsdp->sd_file->ifl_name); 924 return; 925 } 926 927 DBG_CALL(Dbg_syms_updated(ofl, bsdp, symn)); 928 929 bsdp->sd_aux->sa_symspec = bound; 930 bsdp->sd_aux->sa_boundsec = osp; 931 bsdp->sd_flags |= FLG_SY_SPECSEC; 932 bsdp->sd_ref = REF_REL_NEED; 933 bsdp->sd_sym->st_info = ELF_ST_INFO(STB_GLOBAL, STT_NOTYPE); 934 bsdp->sd_sym->st_other = STV_PROTECTED; 935 bsdp->sd_isc = NULL; 936 bsdp->sd_sym->st_size = 0; 937 bsdp->sd_sym->st_value = 0; 938 bsdp->sd_shndx = bsdp->sd_sym->st_shndx = SHN_ABS; 939 } 940 } 941 942 /* 943 * At this point all symbol input processing has been completed, therefore 944 * complete the symbol table entries by generating any necessary internal 945 * symbols. 946 */ 947 uintptr_t 948 ld_sym_spec(Ofl_desc *ofl) 949 { 950 Sym_desc *sdp; 951 Sg_desc *sgp; 952 Aliste idx1; 953 954 if (ofl->ofl_flags & FLG_OF_RELOBJ) 955 return (1); 956 957 DBG_CALL(Dbg_syms_spec_title(ofl->ofl_lml)); 958 959 /* 960 * For each section in the output file, look for symbols named for the 961 * __start/__stop patterns. If references exist, flesh the symbols to 962 * be defined. 963 * 964 * the symbols are given values at the same time as the other special 965 * symbols. 966 */ 967 for (APLIST_TRAVERSE(ofl->ofl_segs, idx1, sgp)) { 968 Os_desc *osp; 969 Aliste idx2; 970 971 for (APLIST_TRAVERSE(sgp->sg_osdescs, idx2, osp)) { 972 sym_add_bounds(ofl, osp, SDAUX_ID_SECBOUND_START); 973 sym_add_bounds(ofl, osp, SDAUX_ID_SECBOUND_STOP); 974 } 975 } 976 977 if (sym_add_spec(MSG_ORIG(MSG_SYM_ETEXT), MSG_ORIG(MSG_SYM_ETEXT_U), 978 SDAUX_ID_ETEXT, 0, (FLG_SY_DEFAULT | FLG_SY_EXPDEF), 979 ofl) == S_ERROR) 980 return (S_ERROR); 981 if (sym_add_spec(MSG_ORIG(MSG_SYM_EDATA), MSG_ORIG(MSG_SYM_EDATA_U), 982 SDAUX_ID_EDATA, 0, (FLG_SY_DEFAULT | FLG_SY_EXPDEF), 983 ofl) == S_ERROR) 984 return (S_ERROR); 985 if (sym_add_spec(MSG_ORIG(MSG_SYM_END), MSG_ORIG(MSG_SYM_END_U), 986 SDAUX_ID_END, FLG_SY_DYNSORT, (FLG_SY_DEFAULT | FLG_SY_EXPDEF), 987 ofl) == S_ERROR) 988 return (S_ERROR); 989 if (sym_add_spec(MSG_ORIG(MSG_SYM_L_END), MSG_ORIG(MSG_SYM_L_END_U), 990 SDAUX_ID_END, 0, FLG_SY_HIDDEN, ofl) == S_ERROR) 991 return (S_ERROR); 992 if (sym_add_spec(MSG_ORIG(MSG_SYM_L_START), MSG_ORIG(MSG_SYM_L_START_U), 993 SDAUX_ID_START, 0, FLG_SY_HIDDEN, ofl) == S_ERROR) 994 return (S_ERROR); 995 996 /* 997 * Historically we've always produced a _DYNAMIC symbol, even for 998 * static executables (in which case its value will be 0). 999 */ 1000 if (sym_add_spec(MSG_ORIG(MSG_SYM_DYNAMIC), MSG_ORIG(MSG_SYM_DYNAMIC_U), 1001 SDAUX_ID_DYN, FLG_SY_DYNSORT, (FLG_SY_DEFAULT | FLG_SY_EXPDEF), 1002 ofl) == S_ERROR) 1003 return (S_ERROR); 1004 1005 if (OFL_ALLOW_DYNSYM(ofl)) 1006 if (sym_add_spec(MSG_ORIG(MSG_SYM_PLKTBL), 1007 MSG_ORIG(MSG_SYM_PLKTBL_U), SDAUX_ID_PLT, 1008 FLG_SY_DYNSORT, (FLG_SY_DEFAULT | FLG_SY_EXPDEF), 1009 ofl) == S_ERROR) 1010 return (S_ERROR); 1011 1012 /* 1013 * A GOT reference will be accompanied by the associated GOT symbol. 1014 * Make sure it gets assigned the appropriate special attributes. 1015 */ 1016 if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_GOFTBL_U), 1017 SYM_NOHASH, NULL, ofl)) != NULL) && (sdp->sd_ref != REF_DYN_SEEN)) { 1018 if (sym_add_spec(MSG_ORIG(MSG_SYM_GOFTBL), 1019 MSG_ORIG(MSG_SYM_GOFTBL_U), SDAUX_ID_GOT, FLG_SY_DYNSORT, 1020 (FLG_SY_DEFAULT | FLG_SY_EXPDEF), ofl) == S_ERROR) 1021 return (S_ERROR); 1022 } 1023 1024 return (1); 1025 } 1026 1027 /* 1028 * Determine a potential capability symbol's visibility. 1029 * 1030 * The -z symbolcap option transforms an object capabilities relocatable object 1031 * into a symbol capabilities relocatable object. Any global function symbols, 1032 * or initialized global data symbols are candidates for transforming into local 1033 * symbol capabilities definitions. However, if a user indicates that a symbol 1034 * should be demoted to local using a mapfile, then there is no need to 1035 * transform the associated global symbol. 1036 * 1037 * Normally, a symbol's visibility is determined after the symbol resolution 1038 * process, after all symbol state has been gathered and resolved. However, 1039 * for -z symbolcap, this determination is too late. When a global symbol is 1040 * read from an input file we need to determine it's visibility so as to decide 1041 * whether to create a local or not. 1042 * 1043 * If a user has explicitly defined this symbol as having local scope within a 1044 * mapfile, then a symbol of the same name already exists. However, explicit 1045 * local definitions are uncommon, as most mapfiles define the global symbol 1046 * requirements together with an auto-reduction directive '*'. If this state 1047 * has been defined, then we must make sure that the new symbol isn't a type 1048 * that can not be demoted to local. 1049 */ 1050 static int 1051 sym_cap_vis(const char *name, Word hash, Sym *sym, Ofl_desc *ofl) 1052 { 1053 Sym_desc *sdp; 1054 uchar_t vis; 1055 avl_index_t where; 1056 sd_flag_t sdflags = 0; 1057 1058 /* 1059 * Determine the visibility of the new symbol. 1060 */ 1061 vis = ELF_ST_VISIBILITY(sym->st_other); 1062 switch (vis) { 1063 case STV_EXPORTED: 1064 sdflags |= FLG_SY_EXPORT; 1065 break; 1066 case STV_SINGLETON: 1067 sdflags |= FLG_SY_SINGLE; 1068 break; 1069 } 1070 1071 /* 1072 * Determine whether a symbol definition already exists, and if so 1073 * obtain the visibility. 1074 */ 1075 if ((sdp = ld_sym_find(name, hash, &where, ofl)) != NULL) 1076 sdflags |= sdp->sd_flags; 1077 1078 /* 1079 * Determine whether the symbol flags indicate this symbol should be 1080 * hidden. 1081 */ 1082 if ((ofl->ofl_flags & (FLG_OF_AUTOLCL | FLG_OF_AUTOELM)) && 1083 ((sdflags & MSK_SY_NOAUTO) == 0)) 1084 sdflags |= FLG_SY_HIDDEN; 1085 1086 return ((sdflags & FLG_SY_HIDDEN) == 0); 1087 } 1088 1089 /* 1090 * This routine checks to see if a symbols visibility needs to be reduced to 1091 * either SYMBOLIC or LOCAL. This routine can be called from either 1092 * reloc_init() or sym_validate(). 1093 */ 1094 void 1095 ld_sym_adjust_vis(Sym_desc *sdp, Ofl_desc *ofl) 1096 { 1097 ofl_flag_t oflags = ofl->ofl_flags; 1098 Sym *sym = sdp->sd_sym; 1099 1100 if ((sdp->sd_ref == REF_REL_NEED) && 1101 (sdp->sd_sym->st_shndx != SHN_UNDEF)) { 1102 /* 1103 * If auto-reduction/elimination is enabled, reduce any 1104 * non-versioned, and non-local capabilities global symbols. 1105 * A symbol is a candidate for auto-reduction/elimination if: 1106 * 1107 * - the symbol wasn't explicitly defined within a mapfile 1108 * (in which case all the necessary state has been applied 1109 * to the symbol), or 1110 * - the symbol isn't one of the family of reserved 1111 * special symbols (ie. _end, _etext, etc.), or 1112 * - the symbol isn't a SINGLETON, or 1113 * - the symbol wasn't explicitly defined within a version 1114 * definition associated with an input relocatable object. 1115 * 1116 * Indicate that the symbol has been reduced as it may be 1117 * necessary to print these symbols later. 1118 */ 1119 if ((oflags & (FLG_OF_AUTOLCL | FLG_OF_AUTOELM)) && 1120 ((sdp->sd_flags & MSK_SY_NOAUTO) == 0)) { 1121 if ((sdp->sd_flags & FLG_SY_HIDDEN) == 0) { 1122 sdp->sd_flags |= 1123 (FLG_SY_REDUCED | FLG_SY_HIDDEN); 1124 } 1125 1126 if (oflags & (FLG_OF_REDLSYM | FLG_OF_AUTOELM)) { 1127 sdp->sd_flags |= FLG_SY_ELIM; 1128 sym->st_other = STV_ELIMINATE | 1129 (sym->st_other & ~MSK_SYM_VISIBILITY); 1130 } else if (ELF_ST_VISIBILITY(sym->st_other) != 1131 STV_INTERNAL) 1132 sym->st_other = STV_HIDDEN | 1133 (sym->st_other & ~MSK_SYM_VISIBILITY); 1134 } 1135 1136 /* 1137 * If -Bsymbolic is in effect, and the symbol hasn't explicitly 1138 * been defined nodirect (via a mapfile), then bind the global 1139 * symbol symbolically and assign the STV_PROTECTED visibility 1140 * attribute. 1141 */ 1142 if ((oflags & FLG_OF_SYMBOLIC) && 1143 ((sdp->sd_flags & (FLG_SY_HIDDEN | FLG_SY_NDIR)) == 0)) { 1144 sdp->sd_flags |= FLG_SY_PROTECT; 1145 if (ELF_ST_VISIBILITY(sym->st_other) == STV_DEFAULT) 1146 sym->st_other = STV_PROTECTED | 1147 (sym->st_other & ~MSK_SYM_VISIBILITY); 1148 } 1149 } 1150 1151 /* 1152 * Indicate that this symbol has had it's visibility checked so that 1153 * we don't need to do this investigation again. 1154 */ 1155 sdp->sd_flags |= FLG_SY_VISIBLE; 1156 } 1157 1158 /* 1159 * Make sure a symbol definition is local to the object being built. 1160 */ 1161 inline static int 1162 ensure_sym_local(Ofl_desc *ofl, Sym_desc *sdp, const char *str) 1163 { 1164 if (sdp->sd_sym->st_shndx == SHN_UNDEF) { 1165 if (str) { 1166 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_SYM_UNDEF), 1167 str, demangle((char *)sdp->sd_name)); 1168 } 1169 return (1); 1170 } 1171 if (sdp->sd_ref != REF_REL_NEED) { 1172 if (str) { 1173 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_SYM_EXTERN), 1174 str, demangle((char *)sdp->sd_name), 1175 sdp->sd_file->ifl_name); 1176 } 1177 return (1); 1178 } 1179 1180 sdp->sd_flags |= FLG_SY_UPREQD; 1181 if (sdp->sd_isc) { 1182 sdp->sd_isc->is_flags |= FLG_IS_SECTREF; 1183 sdp->sd_isc->is_file->ifl_flags |= FLG_IF_FILEREF; 1184 } 1185 return (0); 1186 } 1187 1188 /* 1189 * Make sure all the symbol definitions required for initarray, finiarray, or 1190 * preinitarray's are local to the object being built. 1191 */ 1192 static int 1193 ensure_array_local(Ofl_desc *ofl, APlist *apl, const char *str) 1194 { 1195 Aliste idx; 1196 Sym_desc *sdp; 1197 int ret = 0; 1198 1199 for (APLIST_TRAVERSE(apl, idx, sdp)) 1200 ret += ensure_sym_local(ofl, sdp, str); 1201 1202 return (ret); 1203 } 1204 1205 /* 1206 * After all symbol table input processing has been finished, and all relocation 1207 * counting has been carried out (ie. no more symbols will be read, generated, 1208 * or modified), validate and count the relevant entries: 1209 * 1210 * - check and print any undefined symbols remaining. Note that if a symbol 1211 * has been defined by virtue of the inclusion of an implicit shared 1212 * library, it is still classed as undefined. 1213 * 1214 * - count the number of global needed symbols together with the size of 1215 * their associated name strings (if scoping has been indicated these 1216 * symbols may be reduced to locals). 1217 * 1218 * - establish the size and alignment requirements for the global .bss 1219 * section (the alignment of this section is based on the first symbol 1220 * that it will contain). 1221 */ 1222 uintptr_t 1223 ld_sym_validate(Ofl_desc *ofl) 1224 { 1225 Sym_avlnode *sav; 1226 Sym_desc *sdp; 1227 Sym *sym; 1228 ofl_flag_t oflags = ofl->ofl_flags; 1229 ofl_flag_t undef = 0, needed = 0, verdesc = 0; 1230 Xword bssalign = 0, tlsalign = 0; 1231 Boolean need_bss, need_tlsbss; 1232 Xword bsssize = 0, tlssize = 0; 1233 #if defined(_ELF64) 1234 Xword lbssalign = 0, lbsssize = 0; 1235 Boolean need_lbss; 1236 #endif 1237 int ret, allow_ldynsym; 1238 uchar_t type; 1239 ofl_flag_t undef_state = 0; 1240 1241 DBG_CALL(Dbg_basic_validate(ofl->ofl_lml)); 1242 1243 /* 1244 * The need_XXX booleans are used to determine whether we need to 1245 * create each type of bss section. We used to create these sections 1246 * if the sum of the required sizes for each type were non-zero. 1247 * However, it is possible for a compiler to generate COMMON variables 1248 * of zero-length and this tricks that logic --- even zero-length 1249 * symbols need an output section. 1250 */ 1251 need_bss = need_tlsbss = FALSE; 1252 #if defined(_ELF64) 1253 need_lbss = FALSE; 1254 #endif 1255 1256 /* 1257 * Determine how undefined symbols are handled: 1258 * 1259 * fatal: 1260 * If this link-edit calls for no undefined symbols to remain 1261 * (this is the default case when generating an executable but 1262 * can be enforced for any object using -z defs), a fatal error 1263 * condition will be indicated. 1264 * 1265 * warning: 1266 * If we're creating a shared object, and either the -Bsymbolic 1267 * flag is set, or the user has turned on the -z guidance feature, 1268 * then a non-fatal warning is issued for each symbol. 1269 * 1270 * ignore: 1271 * In all other cases, undefined symbols are quietly allowed. 1272 */ 1273 if (oflags & FLG_OF_NOUNDEF) { 1274 undef = FLG_OF_FATAL; 1275 } else if (oflags & FLG_OF_SHAROBJ) { 1276 if ((oflags & FLG_OF_SYMBOLIC) || 1277 OFL_GUIDANCE(ofl, FLG_OFG_NO_DEFS)) 1278 undef = FLG_OF_WARN; 1279 } 1280 1281 /* 1282 * If the symbol is referenced from an implicitly included shared object 1283 * (ie. it's not on the NEEDED list) then the symbol is also classified 1284 * as undefined and a fatal error condition will be indicated. 1285 */ 1286 if ((oflags & FLG_OF_NOUNDEF) || !(oflags & FLG_OF_SHAROBJ)) 1287 needed = FLG_OF_FATAL; 1288 else if ((oflags & FLG_OF_SHAROBJ) && 1289 OFL_GUIDANCE(ofl, FLG_OFG_NO_DEFS)) 1290 needed = FLG_OF_WARN; 1291 1292 /* 1293 * If the output image is being versioned, then all symbol definitions 1294 * must be associated with a version. Any symbol that isn't associated 1295 * with a version is classified as undefined, and a fatal error 1296 * condition is indicated. 1297 */ 1298 if ((oflags & FLG_OF_VERDEF) && (ofl->ofl_vercnt > VER_NDX_GLOBAL)) 1299 verdesc = FLG_OF_FATAL; 1300 1301 allow_ldynsym = OFL_ALLOW_LDYNSYM(ofl); 1302 1303 if (allow_ldynsym) { 1304 /* 1305 * Normally, we disallow symbols with 0 size from appearing 1306 * in a dyn[sym|tls]sort section. However, there are some 1307 * symbols that serve special purposes that we want to exempt 1308 * from this rule. Look them up, and set their 1309 * FLG_SY_DYNSORT flag. 1310 */ 1311 static const char *special[] = { 1312 MSG_ORIG(MSG_SYM_INIT_U), /* _init */ 1313 MSG_ORIG(MSG_SYM_FINI_U), /* _fini */ 1314 MSG_ORIG(MSG_SYM_START), /* _start */ 1315 NULL 1316 }; 1317 int i; 1318 1319 for (i = 0; special[i] != NULL; i++) { 1320 if (((sdp = ld_sym_find(special[i], 1321 SYM_NOHASH, NULL, ofl)) != NULL) && 1322 (sdp->sd_sym->st_size == 0)) { 1323 if (ld_sym_copy(sdp) == S_ERROR) 1324 return (S_ERROR); 1325 sdp->sd_flags |= FLG_SY_DYNSORT; 1326 } 1327 } 1328 } 1329 1330 /* 1331 * Collect and validate the globals from the internal symbol table. 1332 */ 1333 for (sav = avl_first(&ofl->ofl_symavl); sav; 1334 sav = AVL_NEXT(&ofl->ofl_symavl, sav)) { 1335 Is_desc *isp; 1336 int undeferr = 0; 1337 uchar_t vis; 1338 1339 sdp = sav->sav_sdp; 1340 1341 /* 1342 * If undefined symbols are allowed, and we're not being 1343 * asked to supply guidance, ignore any symbols that are 1344 * not needed. 1345 */ 1346 if (!(oflags & FLG_OF_NOUNDEF) && 1347 !OFL_GUIDANCE(ofl, FLG_OFG_NO_DEFS) && 1348 (sdp->sd_ref == REF_DYN_SEEN)) 1349 continue; 1350 1351 /* 1352 * If the symbol originates from an external or parent mapfile 1353 * reference and hasn't been matched to a reference from a 1354 * relocatable object, ignore it. 1355 */ 1356 if ((sdp->sd_flags & (FLG_SY_EXTERN | FLG_SY_PARENT)) && 1357 ((sdp->sd_flags & FLG_SY_MAPUSED) == 0)) { 1358 sdp->sd_flags |= FLG_SY_INVALID; 1359 continue; 1360 } 1361 1362 sym = sdp->sd_sym; 1363 type = ELF_ST_TYPE(sym->st_info); 1364 1365 /* 1366 * Sanity check TLS. 1367 */ 1368 if ((type == STT_TLS) && (sym->st_size != 0) && 1369 (sym->st_shndx != SHN_UNDEF) && 1370 (sym->st_shndx != SHN_COMMON)) { 1371 Is_desc *isp = sdp->sd_isc; 1372 Ifl_desc *ifl = sdp->sd_file; 1373 1374 if ((isp == NULL) || (isp->is_shdr == NULL) || 1375 ((isp->is_shdr->sh_flags & SHF_TLS) == 0)) { 1376 ld_eprintf(ofl, ERR_FATAL, 1377 MSG_INTL(MSG_SYM_TLS), 1378 demangle(sdp->sd_name), ifl->ifl_name); 1379 continue; 1380 } 1381 } 1382 1383 if ((sdp->sd_flags & FLG_SY_VISIBLE) == 0) 1384 ld_sym_adjust_vis(sdp, ofl); 1385 1386 if ((sdp->sd_flags & FLG_SY_REDUCED) && 1387 (oflags & FLG_OF_PROCRED)) { 1388 DBG_CALL(Dbg_syms_reduce(ofl, DBG_SYM_REDUCE_GLOBAL, 1389 sdp, 0, 0)); 1390 } 1391 1392 /* 1393 * Record any STV_SINGLETON existence. 1394 */ 1395 if ((vis = ELF_ST_VISIBILITY(sym->st_other)) == STV_SINGLETON) 1396 ofl->ofl_dtflags_1 |= DF_1_SINGLETON; 1397 1398 /* 1399 * If building a shared object or executable, and this is a 1400 * non-weak UNDEF symbol with reduced visibility (STV_*), then 1401 * give a fatal error. 1402 */ 1403 if (((oflags & FLG_OF_RELOBJ) == 0) && 1404 (sym->st_shndx == SHN_UNDEF) && 1405 (ELF_ST_BIND(sym->st_info) != STB_WEAK)) { 1406 if (vis && (vis != STV_SINGLETON)) { 1407 sym_undef_entry(ofl, sdp, BNDLOCAL, 1408 FLG_OF_FATAL, &undef_state); 1409 continue; 1410 } 1411 } 1412 1413 /* 1414 * If this symbol is defined in a non-allocatable section, 1415 * reduce it to local symbol. 1416 */ 1417 if (((isp = sdp->sd_isc) != 0) && isp->is_shdr && 1418 ((isp->is_shdr->sh_flags & SHF_ALLOC) == 0)) { 1419 sdp->sd_flags |= (FLG_SY_REDUCED | FLG_SY_HIDDEN); 1420 } 1421 1422 /* 1423 * If this symbol originated as a SHN_SUNW_IGNORE, it will have 1424 * been processed as an SHN_UNDEF. Return the symbol to its 1425 * original index for validation, and propagation to the output 1426 * file. 1427 */ 1428 if (sdp->sd_flags & FLG_SY_IGNORE) 1429 sdp->sd_shndx = SHN_SUNW_IGNORE; 1430 1431 if (undef) { 1432 /* 1433 * If a non-weak reference remains undefined, or if a 1434 * mapfile reference is not bound to the relocatable 1435 * objects that make up the object being built, we have 1436 * a fatal error. 1437 * 1438 * The exceptions are symbols which are defined to be 1439 * found in the parent (FLG_SY_PARENT), which is really 1440 * only meaningful for direct binding, or are defined 1441 * external (FLG_SY_EXTERN) so as to suppress -zdefs 1442 * errors. 1443 * 1444 * Register symbols are always allowed to be UNDEF. 1445 * 1446 * Note that we don't include references created via -u 1447 * in the same shared object binding test. This is for 1448 * backward compatibility, in that a number of archive 1449 * makefile rules used -u to cause archive extraction. 1450 * These same rules have been cut and pasted to apply 1451 * to shared objects, and thus although the -u reference 1452 * is redundant, flagging it as fatal could cause some 1453 * build to fail. Also we have documented the use of 1454 * -u as a mechanism to cause binding to weak version 1455 * definitions, thus giving users an error condition 1456 * would be incorrect. 1457 */ 1458 if (!(sdp->sd_flags & FLG_SY_REGSYM) && 1459 ((sym->st_shndx == SHN_UNDEF) && 1460 ((ELF_ST_BIND(sym->st_info) != STB_WEAK) && 1461 ((sdp->sd_flags & 1462 (FLG_SY_PARENT | FLG_SY_EXTERN)) == 0)) || 1463 ((sdp->sd_flags & 1464 (FLG_SY_MAPREF | FLG_SY_MAPUSED | FLG_SY_HIDDEN | 1465 FLG_SY_PROTECT)) == FLG_SY_MAPREF))) { 1466 sym_undef_entry(ofl, sdp, UNDEF, undef, 1467 &undef_state); 1468 undeferr = 1; 1469 } 1470 1471 } else { 1472 /* 1473 * For building things like shared objects (or anything 1474 * -znodefs), undefined symbols are allowed. 1475 * 1476 * If a mapfile reference remains undefined the user 1477 * would probably like a warning at least (they've 1478 * usually mis-spelt the reference). Refer to the above 1479 * comments for discussion on -u references, which 1480 * are not tested for in the same manner. 1481 */ 1482 if ((sdp->sd_flags & 1483 (FLG_SY_MAPREF | FLG_SY_MAPUSED)) == 1484 FLG_SY_MAPREF) { 1485 sym_undef_entry(ofl, sdp, UNDEF, FLG_OF_WARN, 1486 &undef_state); 1487 undeferr = 1; 1488 } 1489 } 1490 1491 /* 1492 * If this symbol comes from a dependency mark the dependency 1493 * as required (-z ignore can result in unused dependencies 1494 * being dropped). If we need to record dependency versioning 1495 * information indicate what version of the needed shared object 1496 * this symbol is part of. Flag the symbol as undefined if it 1497 * has not been made available to us. 1498 */ 1499 if ((sdp->sd_ref == REF_DYN_NEED) && 1500 (!(sdp->sd_flags & FLG_SY_REFRSD))) { 1501 sdp->sd_file->ifl_flags |= FLG_IF_DEPREQD; 1502 1503 /* 1504 * Capture that we've bound to a symbol that doesn't 1505 * allow being directly bound to. 1506 */ 1507 if (sdp->sd_flags & FLG_SY_NDIR) 1508 ofl->ofl_flags1 |= FLG_OF1_NGLBDIR; 1509 1510 if (sdp->sd_file->ifl_vercnt) { 1511 int vndx; 1512 Ver_index *vip; 1513 1514 vndx = sdp->sd_aux->sa_dverndx; 1515 vip = &sdp->sd_file->ifl_verndx[vndx]; 1516 if (vip->vi_flags & FLG_VER_AVAIL) { 1517 vip->vi_flags |= FLG_VER_REFER; 1518 } else { 1519 sym_undef_entry(ofl, sdp, NOTAVAIL, 1520 FLG_OF_FATAL, &undef_state); 1521 continue; 1522 } 1523 } 1524 } 1525 1526 /* 1527 * Test that we do not bind to symbol supplied from an implicit 1528 * shared object. If a binding is from a weak reference it can 1529 * be ignored. 1530 */ 1531 if (needed && !undeferr && (sdp->sd_flags & FLG_SY_GLOBREF) && 1532 (sdp->sd_ref == REF_DYN_NEED) && 1533 (sdp->sd_flags & FLG_SY_NOTAVAIL)) { 1534 sym_undef_entry(ofl, sdp, IMPLICIT, needed, 1535 &undef_state); 1536 if (needed == FLG_OF_FATAL) 1537 continue; 1538 } 1539 1540 /* 1541 * Test that a symbol isn't going to be reduced to local scope 1542 * which actually wants to bind to a shared object - if so it's 1543 * a fatal error. 1544 */ 1545 if ((sdp->sd_ref == REF_DYN_NEED) && 1546 (sdp->sd_flags & (FLG_SY_HIDDEN | FLG_SY_PROTECT))) { 1547 sym_undef_entry(ofl, sdp, BNDLOCAL, FLG_OF_FATAL, 1548 &undef_state); 1549 continue; 1550 } 1551 1552 /* 1553 * If the output image is to be versioned then all symbol 1554 * definitions must be associated with a version. Remove any 1555 * versioning that might be left associated with an undefined 1556 * symbol. 1557 */ 1558 if (verdesc && (sdp->sd_ref == REF_REL_NEED)) { 1559 if (sym->st_shndx == SHN_UNDEF) { 1560 if (sdp->sd_aux && sdp->sd_aux->sa_overndx) 1561 sdp->sd_aux->sa_overndx = 0; 1562 } else { 1563 if (!SYM_IS_HIDDEN(sdp) && sdp->sd_aux && 1564 (sdp->sd_aux->sa_overndx == 0)) { 1565 sym_undef_entry(ofl, sdp, NOVERSION, 1566 verdesc, &undef_state); 1567 continue; 1568 } 1569 } 1570 } 1571 1572 /* 1573 * If we don't need the symbol there's no need to process it 1574 * any further. 1575 */ 1576 if (sdp->sd_ref == REF_DYN_SEEN) 1577 continue; 1578 1579 /* 1580 * Calculate the size and alignment requirements for the global 1581 * .bss and .tls sections. If we're building a relocatable 1582 * object only account for scoped COMMON symbols (these will 1583 * be converted to .bss references). 1584 * 1585 * When -z nopartial is in effect, partially initialized 1586 * symbols are directed to the special .data section 1587 * created for that purpose (ofl->ofl_isparexpn). 1588 * Otherwise, partially initialized symbols go to .bss. 1589 * 1590 * Also refer to make_mvsections() in sunwmove.c 1591 */ 1592 if ((sym->st_shndx == SHN_COMMON) && 1593 (((oflags & FLG_OF_RELOBJ) == 0) || 1594 (SYM_IS_HIDDEN(sdp) && (oflags & FLG_OF_PROCRED)))) { 1595 if ((sdp->sd_move == NULL) || 1596 ((sdp->sd_flags & FLG_SY_PAREXPN) == 0)) { 1597 if (type != STT_TLS) { 1598 need_bss = TRUE; 1599 bsssize = (Xword)S_ROUND(bsssize, 1600 sym->st_value) + sym->st_size; 1601 if (sym->st_value > bssalign) 1602 bssalign = sym->st_value; 1603 } else { 1604 need_tlsbss = TRUE; 1605 tlssize = (Xword)S_ROUND(tlssize, 1606 sym->st_value) + sym->st_size; 1607 if (sym->st_value > tlsalign) 1608 tlsalign = sym->st_value; 1609 } 1610 } 1611 } 1612 1613 #if defined(_ELF64) 1614 /* 1615 * Calculate the size and alignment requirement for the global 1616 * .lbss. TLS or partially initialized symbols do not need to be 1617 * considered yet. 1618 */ 1619 if ((ld_targ.t_m.m_mach == EM_AMD64) && 1620 (sym->st_shndx == SHN_X86_64_LCOMMON)) { 1621 need_lbss = TRUE; 1622 lbsssize = (Xword)S_ROUND(lbsssize, sym->st_value) + 1623 sym->st_size; 1624 if (sym->st_value > lbssalign) 1625 lbssalign = sym->st_value; 1626 } 1627 #endif 1628 /* 1629 * If a symbol was referenced via the command line 1630 * (ld -u <>, ...), then this counts as a reference against the 1631 * symbol. Mark any section that symbol is defined in. 1632 */ 1633 if (((isp = sdp->sd_isc) != 0) && 1634 (sdp->sd_flags & FLG_SY_CMDREF)) { 1635 isp->is_flags |= FLG_IS_SECTREF; 1636 isp->is_file->ifl_flags |= FLG_IF_FILEREF; 1637 } 1638 1639 /* 1640 * Update the symbol count and the associated name string size. 1641 * Note, a capabilities symbol must remain as visible as a 1642 * global symbol. However, the runtime linker recognizes the 1643 * hidden requirement and ensures the symbol isn't made globally 1644 * available at runtime. 1645 */ 1646 if (SYM_IS_HIDDEN(sdp) && (oflags & FLG_OF_PROCRED)) { 1647 /* 1648 * If any reductions are being processed, keep a count 1649 * of eliminated symbols, and if the symbol is being 1650 * reduced to local, count it's size for the .symtab. 1651 */ 1652 if (sdp->sd_flags & FLG_SY_ELIM) { 1653 ofl->ofl_elimcnt++; 1654 } else { 1655 ofl->ofl_scopecnt++; 1656 if ((((sdp->sd_flags & FLG_SY_REGSYM) == 0) || 1657 sym->st_name) && (st_insert(ofl->ofl_strtab, 1658 sdp->sd_name) == -1)) 1659 return (S_ERROR); 1660 if (allow_ldynsym && sym->st_name && 1661 ldynsym_symtype[type]) { 1662 ofl->ofl_dynscopecnt++; 1663 if (st_insert(ofl->ofl_dynstrtab, 1664 sdp->sd_name) == -1) 1665 return (S_ERROR); 1666 /* Include it in sort section? */ 1667 DYNSORT_COUNT(sdp, sym, type, ++); 1668 } 1669 } 1670 } else { 1671 ofl->ofl_globcnt++; 1672 1673 /* 1674 * Check to see if this global variable should go into 1675 * a sort section. Sort sections require a 1676 * .SUNW_ldynsym section, so, don't check unless a 1677 * .SUNW_ldynsym is allowed. 1678 */ 1679 if (allow_ldynsym) 1680 DYNSORT_COUNT(sdp, sym, type, ++); 1681 1682 /* 1683 * If global direct bindings are in effect, or this 1684 * symbol has bound to a dependency which was specified 1685 * as requiring direct bindings, and it hasn't 1686 * explicitly been defined as a non-direct binding 1687 * symbol, mark it. 1688 */ 1689 if (((ofl->ofl_dtflags_1 & DF_1_DIRECT) || (isp && 1690 (isp->is_file->ifl_flags & FLG_IF_DIRECT))) && 1691 ((sdp->sd_flags & FLG_SY_NDIR) == 0)) 1692 sdp->sd_flags |= FLG_SY_DIR; 1693 1694 /* 1695 * Insert the symbol name. 1696 */ 1697 if (((sdp->sd_flags & FLG_SY_REGSYM) == 0) || 1698 sym->st_name) { 1699 if (st_insert(ofl->ofl_strtab, 1700 sdp->sd_name) == -1) 1701 return (S_ERROR); 1702 1703 if (!(ofl->ofl_flags & FLG_OF_RELOBJ) && 1704 (st_insert(ofl->ofl_dynstrtab, 1705 sdp->sd_name) == -1)) 1706 return (S_ERROR); 1707 } 1708 1709 /* 1710 * If this section offers a global symbol - record that 1711 * fact. 1712 */ 1713 if (isp) { 1714 isp->is_flags |= FLG_IS_SECTREF; 1715 isp->is_file->ifl_flags |= FLG_IF_FILEREF; 1716 } 1717 } 1718 } 1719 1720 /* 1721 * Guidance: Use -z defs|nodefs when building shared objects. 1722 * 1723 * Our caller issues this, unless we mask it out here. So we mask it 1724 * out unless we've issued at least one warnings or fatal error. 1725 */ 1726 if (!((oflags & FLG_OF_SHAROBJ) && OFL_GUIDANCE(ofl, FLG_OFG_NO_DEFS) && 1727 (undef_state & (FLG_OF_FATAL | FLG_OF_WARN)))) 1728 ofl->ofl_guideflags |= FLG_OFG_NO_DEFS; 1729 1730 /* 1731 * If we've encountered a fatal error during symbol validation then 1732 * return now. 1733 */ 1734 if (ofl->ofl_flags & FLG_OF_FATAL) 1735 return (1); 1736 1737 /* 1738 * Now that symbol resolution is completed, scan any register symbols. 1739 * From now on, we're only interested in those that contribute to the 1740 * output file. 1741 */ 1742 if (ofl->ofl_regsyms) { 1743 int ndx; 1744 1745 for (ndx = 0; ndx < ofl->ofl_regsymsno; ndx++) { 1746 if ((sdp = ofl->ofl_regsyms[ndx]) == NULL) 1747 continue; 1748 if (sdp->sd_ref != REF_REL_NEED) { 1749 ofl->ofl_regsyms[ndx] = NULL; 1750 continue; 1751 } 1752 1753 ofl->ofl_regsymcnt++; 1754 if (sdp->sd_sym->st_name == 0) 1755 sdp->sd_name = MSG_ORIG(MSG_STR_EMPTY); 1756 1757 if (SYM_IS_HIDDEN(sdp) || 1758 (ELF_ST_BIND(sdp->sd_sym->st_info) == STB_LOCAL)) 1759 ofl->ofl_lregsymcnt++; 1760 } 1761 } 1762 1763 /* 1764 * Generate the .bss section now that we know its size and alignment. 1765 */ 1766 if (need_bss) { 1767 if (ld_make_bss(ofl, bsssize, bssalign, 1768 ld_targ.t_id.id_bss) == S_ERROR) 1769 return (S_ERROR); 1770 } 1771 if (need_tlsbss) { 1772 if (ld_make_bss(ofl, tlssize, tlsalign, 1773 ld_targ.t_id.id_tlsbss) == S_ERROR) 1774 return (S_ERROR); 1775 } 1776 #if defined(_ELF64) 1777 if ((ld_targ.t_m.m_mach == EM_AMD64) && 1778 need_lbss && !(oflags & FLG_OF_RELOBJ)) { 1779 if (ld_make_bss(ofl, lbsssize, lbssalign, 1780 ld_targ.t_id.id_lbss) == S_ERROR) 1781 return (S_ERROR); 1782 } 1783 #endif 1784 /* 1785 * Determine what entry point symbol we need, and if found save its 1786 * symbol descriptor so that we can update the ELF header entry with the 1787 * symbols value later (see update_oehdr). Make sure the symbol is 1788 * tagged to ensure its update in case -s is in effect. Use any -e 1789 * option first, or the default entry points `_start' and `main'. 1790 */ 1791 ret = 0; 1792 if (ofl->ofl_entry) { 1793 if ((sdp = ld_sym_find(ofl->ofl_entry, SYM_NOHASH, 1794 NULL, ofl)) == NULL) { 1795 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_ARG_NOENTRY), 1796 ofl->ofl_entry); 1797 ret++; 1798 } else if (ensure_sym_local(ofl, sdp, 1799 MSG_INTL(MSG_SYM_ENTRY)) != 0) { 1800 ret++; 1801 } else { 1802 ofl->ofl_entry = (void *)sdp; 1803 } 1804 } else if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_START), 1805 SYM_NOHASH, NULL, ofl)) != NULL) && (ensure_sym_local(ofl, 1806 sdp, 0) == 0)) { 1807 ofl->ofl_entry = (void *)sdp; 1808 1809 } else if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_MAIN), 1810 SYM_NOHASH, NULL, ofl)) != NULL) && (ensure_sym_local(ofl, 1811 sdp, 0) == 0)) { 1812 ofl->ofl_entry = (void *)sdp; 1813 } 1814 1815 /* 1816 * If ld -zdtrace=<sym> was given, then validate that the symbol is 1817 * defined within the current object being built. 1818 */ 1819 if ((sdp = ofl->ofl_dtracesym) != 0) 1820 ret += ensure_sym_local(ofl, sdp, MSG_ORIG(MSG_STR_DTRACE)); 1821 1822 /* 1823 * If any initarray, finiarray or preinitarray functions have been 1824 * requested, make sure they are defined within the current object 1825 * being built. 1826 */ 1827 if (ofl->ofl_initarray) { 1828 ret += ensure_array_local(ofl, ofl->ofl_initarray, 1829 MSG_ORIG(MSG_SYM_INITARRAY)); 1830 } 1831 if (ofl->ofl_finiarray) { 1832 ret += ensure_array_local(ofl, ofl->ofl_finiarray, 1833 MSG_ORIG(MSG_SYM_FINIARRAY)); 1834 } 1835 if (ofl->ofl_preiarray) { 1836 ret += ensure_array_local(ofl, ofl->ofl_preiarray, 1837 MSG_ORIG(MSG_SYM_PREINITARRAY)); 1838 } 1839 1840 if (ret) 1841 return (S_ERROR); 1842 1843 /* 1844 * If we're required to record any needed dependencies versioning 1845 * information calculate it now that all symbols have been validated. 1846 */ 1847 if ((oflags & (FLG_OF_VERNEED | FLG_OF_NOVERSEC)) == FLG_OF_VERNEED) 1848 return (ld_vers_check_need(ofl)); 1849 else 1850 return (1); 1851 } 1852 1853 /* 1854 * qsort(3c) comparison function. As an optimization for associating weak 1855 * symbols to their strong counterparts sort global symbols according to their 1856 * section index, address and binding. 1857 */ 1858 static int 1859 compare(const void *sdpp1, const void *sdpp2) 1860 { 1861 Sym_desc *sdp1 = *((Sym_desc **)sdpp1); 1862 Sym_desc *sdp2 = *((Sym_desc **)sdpp2); 1863 Sym *sym1, *sym2; 1864 uchar_t bind1, bind2; 1865 1866 /* 1867 * Symbol descriptors may be zero, move these to the front of the 1868 * sorted array. 1869 */ 1870 if (sdp1 == NULL) 1871 return (-1); 1872 if (sdp2 == NULL) 1873 return (1); 1874 1875 sym1 = sdp1->sd_sym; 1876 sym2 = sdp2->sd_sym; 1877 1878 /* 1879 * Compare the symbols section index. This is important when sorting 1880 * the symbol tables of relocatable objects. In this case, a symbols 1881 * value is the offset within the associated section, and thus many 1882 * symbols can have the same value, but are effectively different 1883 * addresses. 1884 */ 1885 if (sym1->st_shndx > sym2->st_shndx) 1886 return (1); 1887 if (sym1->st_shndx < sym2->st_shndx) 1888 return (-1); 1889 1890 /* 1891 * Compare the symbols value (address). 1892 */ 1893 if (sym1->st_value > sym2->st_value) 1894 return (1); 1895 if (sym1->st_value < sym2->st_value) 1896 return (-1); 1897 1898 bind1 = ELF_ST_BIND(sym1->st_info); 1899 bind2 = ELF_ST_BIND(sym2->st_info); 1900 1901 /* 1902 * If two symbols have the same address place the weak symbol before 1903 * any strong counterpart. 1904 */ 1905 if (bind1 > bind2) 1906 return (-1); 1907 if (bind1 < bind2) 1908 return (1); 1909 1910 return (0); 1911 } 1912 1913 /* 1914 * Issue a MSG_SYM_BADADDR error from ld_sym_process(). This error 1915 * is issued when a symbol address/size is not contained by the 1916 * target section. 1917 * 1918 * Such objects are at least partially corrupt, and the user would 1919 * be well advised to be skeptical of them, and to ask their compiler 1920 * supplier to fix the problem. However, a distinction needs to be 1921 * made between symbols that reference readonly text, and those that 1922 * access writable data. Other than throwing off profiling results, 1923 * the readonly section case is less serious. We have encountered 1924 * such objects in the field. In order to allow existing objects 1925 * to continue working, we issue a warning rather than a fatal error 1926 * if the symbol is against readonly text. Other cases are fatal. 1927 */ 1928 static void 1929 issue_badaddr_msg(Ifl_desc *ifl, Ofl_desc *ofl, Sym_desc *sdp, 1930 Sym *sym, Word shndx) 1931 { 1932 Error err; 1933 const char *msg; 1934 1935 if ((sdp->sd_isc->is_shdr->sh_flags & (SHF_WRITE | SHF_ALLOC)) == 1936 SHF_ALLOC) { 1937 msg = MSG_INTL(MSG_SYM_BADADDR_ROTXT); 1938 err = ERR_WARNING; 1939 } else { 1940 msg = MSG_INTL(MSG_SYM_BADADDR); 1941 err = ERR_FATAL; 1942 } 1943 1944 ld_eprintf(ofl, err, msg, demangle(sdp->sd_name), 1945 ifl->ifl_name, shndx, sdp->sd_isc->is_name, 1946 EC_XWORD(sdp->sd_isc->is_shdr->sh_size), 1947 EC_XWORD(sym->st_value), EC_XWORD(sym->st_size)); 1948 } 1949 1950 /* 1951 * Global symbols that are candidates for translation to local capability 1952 * symbols under -z symbolcap, are maintained on a local symbol list. Once 1953 * all symbols of a file are processed, this list is traversed to cull any 1954 * unnecessary weak symbol aliases. 1955 */ 1956 typedef struct { 1957 Sym_desc *c_nsdp; /* new lead symbol */ 1958 Sym_desc *c_osdp; /* original symbol */ 1959 Cap_group *c_group; /* symbol capability group */ 1960 Word c_ndx; /* symbol index */ 1961 } Cap_pair; 1962 1963 /* 1964 * Process the symbol table for the specified input file. At this point all 1965 * input sections from this input file have been assigned an input section 1966 * descriptor which is saved in the `ifl_isdesc' array. 1967 * 1968 * - local symbols are saved (as is) if the input file is a relocatable 1969 * object 1970 * 1971 * - global symbols are added to the linkers internal symbol table if they 1972 * are not already present, otherwise a symbol resolution function is 1973 * called upon to resolve the conflict. 1974 */ 1975 uintptr_t 1976 ld_sym_process(Is_desc *isc, Ifl_desc *ifl, Ofl_desc *ofl) 1977 { 1978 /* 1979 * This macro tests the given symbol to see if it is out of 1980 * range relative to the section it references. 1981 * 1982 * entry: 1983 * - ifl is a relative object (ET_REL) 1984 * _sdp - Symbol descriptor 1985 * _sym - Symbol 1986 * _type - Symbol type 1987 * 1988 * The following are tested: 1989 * - Symbol length is non-zero 1990 * - Symbol type is a type that references code or data 1991 * - Referenced section is not 0 (indicates an UNDEF symbol) 1992 * and is not in the range of special values above SHN_LORESERVE 1993 * (excluding SHN_XINDEX, which is OK). 1994 * - We have a valid section header for the target section 1995 * 1996 * If the above are all true, and the symbol position is not 1997 * contained by the target section, this macro evaluates to 1998 * True (1). Otherwise, False(0). 1999 */ 2000 #define SYM_LOC_BADADDR(_sdp, _sym, _type) \ 2001 (_sym->st_size && dynsymsort_symtype[_type] && \ 2002 (_sym->st_shndx != SHN_UNDEF) && \ 2003 ((_sym->st_shndx < SHN_LORESERVE) || \ 2004 (_sym->st_shndx == SHN_XINDEX)) && \ 2005 _sdp->sd_isc && _sdp->sd_isc->is_shdr && \ 2006 ((_sym->st_value + _sym->st_size) > _sdp->sd_isc->is_shdr->sh_size)) 2007 2008 Conv_inv_buf_t inv_buf; 2009 Sym *sym = (Sym *)isc->is_indata->d_buf; 2010 Word *symshndx = NULL; 2011 Shdr *shdr = isc->is_shdr; 2012 Sym_desc *sdp; 2013 size_t strsize; 2014 char *strs; 2015 uchar_t type, bind; 2016 Word ndx, hash, local, total; 2017 uchar_t osabi = ifl->ifl_ehdr->e_ident[EI_OSABI]; 2018 Half mach = ifl->ifl_ehdr->e_machine; 2019 Half etype = ifl->ifl_ehdr->e_type; 2020 int etype_rel; 2021 const char *symsecname, *strsecname; 2022 Word symsecndx; 2023 avl_index_t where; 2024 int test_gnu_hidden_bit, weak; 2025 Cap_desc *cdp = NULL; 2026 Alist *cappairs = NULL; 2027 2028 /* 2029 * Its possible that a file may contain more that one symbol table, 2030 * ie. .dynsym and .symtab in a shared library. Only process the first 2031 * table (here, we assume .dynsym comes before .symtab). 2032 */ 2033 if (ifl->ifl_symscnt) 2034 return (1); 2035 2036 if (isc->is_symshndx) 2037 symshndx = isc->is_symshndx->is_indata->d_buf; 2038 2039 DBG_CALL(Dbg_syms_process(ofl->ofl_lml, ifl)); 2040 2041 symsecndx = isc->is_scnndx; 2042 if (isc->is_name) 2043 symsecname = isc->is_name; 2044 else 2045 symsecname = MSG_ORIG(MSG_STR_EMPTY); 2046 2047 /* 2048 * From the symbol tables section header information determine which 2049 * strtab table is needed to locate the actual symbol names. 2050 */ 2051 if (ifl->ifl_flags & FLG_IF_HSTRTAB) { 2052 ndx = shdr->sh_link; 2053 if ((ndx == 0) || (ndx >= ifl->ifl_shnum)) { 2054 ld_eprintf(ofl, ERR_FATAL, 2055 MSG_INTL(MSG_FIL_INVSHLINK), ifl->ifl_name, 2056 EC_WORD(symsecndx), symsecname, EC_XWORD(ndx)); 2057 return (S_ERROR); 2058 } 2059 strsize = ifl->ifl_isdesc[ndx]->is_shdr->sh_size; 2060 strs = ifl->ifl_isdesc[ndx]->is_indata->d_buf; 2061 if (ifl->ifl_isdesc[ndx]->is_name) 2062 strsecname = ifl->ifl_isdesc[ndx]->is_name; 2063 else 2064 strsecname = MSG_ORIG(MSG_STR_EMPTY); 2065 } else { 2066 /* 2067 * There is no string table section in this input file 2068 * although there are symbols in this symbol table section. 2069 * This means that these symbols do not have names. 2070 * Currently, only scratch register symbols are allowed 2071 * not to have names. 2072 */ 2073 strsize = 0; 2074 strs = (char *)MSG_ORIG(MSG_STR_EMPTY); 2075 strsecname = MSG_ORIG(MSG_STR_EMPTY); 2076 } 2077 2078 /* 2079 * Determine the number of local symbols together with the total 2080 * number we have to process. 2081 */ 2082 total = (Word)(shdr->sh_size / shdr->sh_entsize); 2083 local = shdr->sh_info; 2084 2085 /* 2086 * Allocate a symbol table index array and a local symbol array 2087 * (global symbols are processed and added to the ofl->ofl_symbkt[] 2088 * array). If we are dealing with a relocatable object, allocate the 2089 * local symbol descriptors. If this isn't a relocatable object we 2090 * still have to process any shared object locals to determine if any 2091 * register symbols exist. Although these aren't added to the output 2092 * image, they are used as part of symbol resolution. 2093 */ 2094 if ((ifl->ifl_oldndx = libld_malloc((size_t)(total * 2095 sizeof (Sym_desc *)))) == NULL) 2096 return (S_ERROR); 2097 etype_rel = (etype == ET_REL); 2098 if (etype_rel && local) { 2099 if ((ifl->ifl_locs = 2100 libld_calloc(sizeof (Sym_desc), local)) == NULL) 2101 return (S_ERROR); 2102 /* LINTED */ 2103 ifl->ifl_locscnt = (Word)local; 2104 } 2105 ifl->ifl_symscnt = total; 2106 2107 /* 2108 * If there are local symbols to save add them to the symbol table 2109 * index array. 2110 */ 2111 if (local) { 2112 int allow_ldynsym = OFL_ALLOW_LDYNSYM(ofl); 2113 Sym_desc *last_file_sdp = NULL; 2114 int last_file_ndx = 0; 2115 2116 for (sym++, ndx = 1; ndx < local; sym++, ndx++) { 2117 sd_flag_t sdflags = FLG_SY_CLEAN; 2118 Word shndx; 2119 const char *name; 2120 Sym_desc *rsdp; 2121 int shndx_bad = 0; 2122 int symtab_enter = 1; 2123 2124 /* 2125 * Determine and validate the associated section index. 2126 */ 2127 if (symshndx && (sym->st_shndx == SHN_XINDEX)) { 2128 shndx = symshndx[ndx]; 2129 } else if ((shndx = sym->st_shndx) >= SHN_LORESERVE) { 2130 sdflags |= FLG_SY_SPECSEC; 2131 } else if (shndx > ifl->ifl_shnum) { 2132 /* We need the name before we can issue error */ 2133 shndx_bad = 1; 2134 } 2135 2136 /* 2137 * Check if st_name has a valid value or not. 2138 */ 2139 if ((name = string(ofl, ifl, sym, strs, strsize, ndx, 2140 shndx, symsecndx, symsecname, strsecname, 2141 &sdflags)) == NULL) 2142 continue; 2143 2144 /* 2145 * Now that we have the name, if the section index 2146 * was bad, report it. 2147 */ 2148 if (shndx_bad) { 2149 ld_eprintf(ofl, ERR_WARNING, 2150 MSG_INTL(MSG_SYM_INVSHNDX), 2151 demangle_symname(name, symsecname, ndx), 2152 ifl->ifl_name, 2153 conv_sym_shndx(osabi, mach, sym->st_shndx, 2154 CONV_FMT_DECIMAL, &inv_buf)); 2155 continue; 2156 } 2157 2158 /* 2159 * If this local symbol table originates from a shared 2160 * object, then we're only interested in recording 2161 * register symbols. As local symbol descriptors aren't 2162 * allocated for shared objects, one will be allocated 2163 * to associated with the register symbol. This symbol 2164 * won't become part of the output image, but we must 2165 * process it to test for register conflicts. 2166 */ 2167 rsdp = sdp = NULL; 2168 if (sdflags & FLG_SY_REGSYM) { 2169 /* 2170 * The presence of FLG_SY_REGSYM means that 2171 * the pointers in ld_targ.t_ms are non-NULL. 2172 */ 2173 rsdp = (*ld_targ.t_ms.ms_reg_find)(sym, ofl); 2174 if (rsdp != 0) { 2175 /* 2176 * The fact that another register def- 2177 * inition has been found is fatal. 2178 * Call the verification routine to get 2179 * the error message and move on. 2180 */ 2181 (void) (*ld_targ.t_ms.ms_reg_check) 2182 (rsdp, sym, name, ifl, ofl); 2183 continue; 2184 } 2185 2186 if (etype == ET_DYN) { 2187 if ((sdp = libld_calloc( 2188 sizeof (Sym_desc), 1)) == NULL) 2189 return (S_ERROR); 2190 sdp->sd_ref = REF_DYN_SEEN; 2191 2192 /* Will not appear in output object */ 2193 symtab_enter = 0; 2194 } 2195 } else if (etype == ET_DYN) 2196 continue; 2197 2198 /* 2199 * Fill in the remaining symbol descriptor information. 2200 */ 2201 if (sdp == NULL) { 2202 sdp = &(ifl->ifl_locs[ndx]); 2203 sdp->sd_ref = REF_REL_NEED; 2204 sdp->sd_symndx = ndx; 2205 } 2206 if (rsdp == NULL) { 2207 sdp->sd_name = name; 2208 sdp->sd_sym = sym; 2209 sdp->sd_shndx = shndx; 2210 sdp->sd_flags = sdflags; 2211 sdp->sd_file = ifl; 2212 ifl->ifl_oldndx[ndx] = sdp; 2213 } 2214 2215 DBG_CALL(Dbg_syms_entry(ofl->ofl_lml, ndx, sdp)); 2216 2217 /* 2218 * Reclassify any SHN_SUNW_IGNORE symbols to SHN_UNDEF 2219 * so as to simplify future processing. 2220 */ 2221 if (sym->st_shndx == SHN_SUNW_IGNORE) { 2222 sdp->sd_shndx = shndx = SHN_UNDEF; 2223 sdp->sd_flags |= (FLG_SY_IGNORE | FLG_SY_ELIM); 2224 } 2225 2226 /* 2227 * Process any register symbols. 2228 */ 2229 if (sdp->sd_flags & FLG_SY_REGSYM) { 2230 /* 2231 * Add a diagnostic to indicate we've caught a 2232 * register symbol, as this can be useful if a 2233 * register conflict is later discovered. 2234 */ 2235 DBG_CALL(Dbg_syms_entered(ofl, sym, sdp)); 2236 2237 /* 2238 * If this register symbol hasn't already been 2239 * recorded, enter it now. 2240 * 2241 * The presence of FLG_SY_REGSYM means that 2242 * the pointers in ld_targ.t_ms are non-NULL. 2243 */ 2244 if ((rsdp == NULL) && 2245 ((*ld_targ.t_ms.ms_reg_enter)(sdp, ofl) == 2246 0)) 2247 return (S_ERROR); 2248 } 2249 2250 /* 2251 * Assign an input section. 2252 */ 2253 if ((sym->st_shndx != SHN_UNDEF) && 2254 ((sdp->sd_flags & FLG_SY_SPECSEC) == 0)) 2255 sdp->sd_isc = ifl->ifl_isdesc[shndx]; 2256 2257 /* 2258 * If this symbol falls within the range of a section 2259 * being discarded, then discard the symbol itself. 2260 * There is no reason to keep this local symbol. 2261 */ 2262 if (sdp->sd_isc && 2263 (sdp->sd_isc->is_flags & FLG_IS_DISCARD)) { 2264 sdp->sd_flags |= FLG_SY_ISDISC; 2265 DBG_CALL(Dbg_syms_discarded(ofl->ofl_lml, sdp)); 2266 continue; 2267 } 2268 2269 /* 2270 * Skip any section symbols as new versions of these 2271 * will be created. 2272 */ 2273 if ((type = ELF_ST_TYPE(sym->st_info)) == STT_SECTION) { 2274 if (sym->st_shndx == SHN_UNDEF) { 2275 ld_eprintf(ofl, ERR_WARNING, 2276 MSG_INTL(MSG_SYM_INVSHNDX), 2277 demangle_symname(name, symsecname, 2278 ndx), ifl->ifl_name, 2279 conv_sym_shndx(osabi, mach, 2280 sym->st_shndx, CONV_FMT_DECIMAL, 2281 &inv_buf)); 2282 } 2283 continue; 2284 } 2285 2286 /* 2287 * For a relocatable object, if this symbol is defined 2288 * and has non-zero length and references an address 2289 * within an associated section, then check its extents 2290 * to make sure the section boundaries encompass it. 2291 * If they don't, the ELF file is corrupt. 2292 */ 2293 if (etype_rel) { 2294 if (SYM_LOC_BADADDR(sdp, sym, type)) { 2295 issue_badaddr_msg(ifl, ofl, sdp, 2296 sym, shndx); 2297 if (ofl->ofl_flags & FLG_OF_FATAL) 2298 continue; 2299 } 2300 2301 /* 2302 * We have observed relocatable objects 2303 * containing identical adjacent STT_FILE 2304 * symbols. Discard any other than the first, 2305 * as they are all equivalent and the extras 2306 * do not add information. 2307 * 2308 * For the purpose of this test, we assume 2309 * that only the symbol type and the string 2310 * table offset (st_name) matter. 2311 */ 2312 if (type == STT_FILE) { 2313 int toss = (last_file_sdp != NULL) && 2314 ((ndx - 1) == last_file_ndx) && 2315 (sym->st_name == 2316 last_file_sdp->sd_sym->st_name); 2317 2318 last_file_sdp = sdp; 2319 last_file_ndx = ndx; 2320 if (toss) { 2321 sdp->sd_flags |= FLG_SY_INVALID; 2322 DBG_CALL(Dbg_syms_dup_discarded( 2323 ofl->ofl_lml, ndx, sdp)); 2324 continue; 2325 } 2326 } 2327 } 2328 2329 2330 /* 2331 * Sanity check for TLS 2332 */ 2333 if ((sym->st_size != 0) && ((type == STT_TLS) && 2334 (sym->st_shndx != SHN_COMMON))) { 2335 Is_desc *isp = sdp->sd_isc; 2336 2337 if ((isp == NULL) || (isp->is_shdr == NULL) || 2338 ((isp->is_shdr->sh_flags & SHF_TLS) == 0)) { 2339 ld_eprintf(ofl, ERR_FATAL, 2340 MSG_INTL(MSG_SYM_TLS), 2341 demangle(sdp->sd_name), 2342 ifl->ifl_name); 2343 continue; 2344 } 2345 } 2346 2347 /* 2348 * Carry our some basic sanity checks (these are just 2349 * some of the erroneous symbol entries we've come 2350 * across, there's probably a lot more). The symbol 2351 * will not be carried forward to the output file, which 2352 * won't be a problem unless a relocation is required 2353 * against it. 2354 */ 2355 if (((sdp->sd_flags & FLG_SY_SPECSEC) && 2356 ((sym->st_shndx == SHN_COMMON)) || 2357 ((type == STT_FILE) && 2358 (sym->st_shndx != SHN_ABS))) || 2359 (sdp->sd_isc && (sdp->sd_isc->is_osdesc == NULL))) { 2360 ld_eprintf(ofl, ERR_WARNING, 2361 MSG_INTL(MSG_SYM_INVSHNDX), 2362 demangle_symname(name, symsecname, ndx), 2363 ifl->ifl_name, 2364 conv_sym_shndx(osabi, mach, sym->st_shndx, 2365 CONV_FMT_DECIMAL, &inv_buf)); 2366 sdp->sd_isc = NULL; 2367 sdp->sd_flags |= FLG_SY_INVALID; 2368 continue; 2369 } 2370 2371 /* 2372 * As these local symbols will become part of the output 2373 * image, record their number and name string size. 2374 * Globals are counted after all input file processing 2375 * (and hence symbol resolution) is complete during 2376 * sym_validate(). 2377 */ 2378 if (!(ofl->ofl_flags & FLG_OF_REDLSYM) && 2379 symtab_enter) { 2380 ofl->ofl_locscnt++; 2381 2382 if ((((sdp->sd_flags & FLG_SY_REGSYM) == 0) || 2383 sym->st_name) && (st_insert(ofl->ofl_strtab, 2384 sdp->sd_name) == -1)) 2385 return (S_ERROR); 2386 2387 if (allow_ldynsym && sym->st_name && 2388 ldynsym_symtype[type]) { 2389 ofl->ofl_dynlocscnt++; 2390 if (st_insert(ofl->ofl_dynstrtab, 2391 sdp->sd_name) == -1) 2392 return (S_ERROR); 2393 /* Include it in sort section? */ 2394 DYNSORT_COUNT(sdp, sym, type, ++); 2395 } 2396 } 2397 } 2398 } 2399 2400 /* 2401 * The GNU ld interprets the top bit of the 16-bit Versym value 2402 * (0x8000) as the "hidden" bit. If this bit is set, the linker 2403 * is supposed to act as if that symbol does not exist. The Solaris 2404 * linker does not support this mechanism, or the model of interface 2405 * evolution that it allows, but we honor it in GNU ld produced 2406 * objects in order to interoperate with them. 2407 * 2408 * Determine if we should honor the GNU hidden bit for this file. 2409 */ 2410 test_gnu_hidden_bit = ((ifl->ifl_flags & FLG_IF_GNUVER) != 0) && 2411 (ifl->ifl_versym != NULL); 2412 2413 /* 2414 * Determine whether object capabilities for this file are being 2415 * converted into symbol capabilities. If so, global function symbols, 2416 * and initialized global data symbols, need special translation and 2417 * processing. 2418 */ 2419 if ((etype == ET_REL) && (ifl->ifl_flags & FLG_IF_OTOSCAP)) 2420 cdp = ifl->ifl_caps; 2421 2422 /* 2423 * Now scan the global symbols entering them in the internal symbol 2424 * table or resolving them as necessary. 2425 */ 2426 sym = (Sym *)isc->is_indata->d_buf; 2427 sym += local; 2428 weak = 0; 2429 /* LINTED */ 2430 for (ndx = (int)local; ndx < total; sym++, ndx++) { 2431 const char *name; 2432 sd_flag_t sdflags = 0; 2433 Word shndx; 2434 int shndx_bad = 0; 2435 Sym *nsym = sym; 2436 Cap_pair *cpp = NULL; 2437 uchar_t ntype; 2438 2439 /* 2440 * Determine and validate the associated section index. 2441 */ 2442 if (symshndx && (nsym->st_shndx == SHN_XINDEX)) { 2443 shndx = symshndx[ndx]; 2444 } else if ((shndx = nsym->st_shndx) >= SHN_LORESERVE) { 2445 sdflags |= FLG_SY_SPECSEC; 2446 } else if (shndx > ifl->ifl_shnum) { 2447 /* We need the name before we can issue error */ 2448 shndx_bad = 1; 2449 } 2450 2451 /* 2452 * Check if st_name has a valid value or not. 2453 */ 2454 if ((name = string(ofl, ifl, nsym, strs, strsize, ndx, shndx, 2455 symsecndx, symsecname, strsecname, &sdflags)) == NULL) 2456 continue; 2457 2458 /* 2459 * Now that we have the name, report an erroneous section index. 2460 */ 2461 if (shndx_bad) { 2462 ld_eprintf(ofl, ERR_WARNING, MSG_INTL(MSG_SYM_INVSHNDX), 2463 demangle_symname(name, symsecname, ndx), 2464 ifl->ifl_name, 2465 conv_sym_shndx(osabi, mach, nsym->st_shndx, 2466 CONV_FMT_DECIMAL, &inv_buf)); 2467 continue; 2468 } 2469 2470 /* 2471 * Test for the GNU hidden bit, and ignore symbols that 2472 * have it set. 2473 */ 2474 if (test_gnu_hidden_bit && 2475 ((ifl->ifl_versym[ndx] & 0x8000) != 0)) 2476 continue; 2477 2478 /* 2479 * The linker itself will generate symbols for _end, _etext, 2480 * _edata, _DYNAMIC and _PROCEDURE_LINKAGE_TABLE_, so don't 2481 * bother entering these symbols from shared objects. This 2482 * results in some wasted resolution processing, which is hard 2483 * to feel, but if nothing else, pollutes diagnostic relocation 2484 * output. 2485 */ 2486 if (name[0] && (etype == ET_DYN) && (nsym->st_size == 0) && 2487 (ELF_ST_TYPE(nsym->st_info) == STT_OBJECT) && 2488 (name[0] == '_') && ((name[1] == 'e') || 2489 (name[1] == 'D') || (name[1] == 'P')) && 2490 ((strcmp(name, MSG_ORIG(MSG_SYM_ETEXT_U)) == 0) || 2491 (strcmp(name, MSG_ORIG(MSG_SYM_EDATA_U)) == 0) || 2492 (strcmp(name, MSG_ORIG(MSG_SYM_END_U)) == 0) || 2493 (strcmp(name, MSG_ORIG(MSG_SYM_DYNAMIC_U)) == 0) || 2494 (strcmp(name, MSG_ORIG(MSG_SYM_PLKTBL_U)) == 0))) { 2495 ifl->ifl_oldndx[ndx] = 0; 2496 continue; 2497 } 2498 2499 /* 2500 * The '-z wrap=XXX' option emulates the GNU ld --wrap=XXX 2501 * option. When XXX is the symbol to be wrapped: 2502 * 2503 * - An undefined reference to XXX is converted to __wrap_XXX 2504 * - An undefined reference to __real_XXX is converted to XXX 2505 * 2506 * The idea is that the user can supply a wrapper function 2507 * __wrap_XXX that does some work, and then uses the name 2508 * __real_XXX to pass the call on to the real function. The 2509 * wrapper objects are linked with the original unmodified 2510 * objects to produce a wrapped version of the output object. 2511 */ 2512 if (ofl->ofl_wrap && name[0] && (shndx == SHN_UNDEF)) { 2513 WrapSymNode wsn, *wsnp; 2514 2515 /* 2516 * If this is the __real_XXX form, advance the 2517 * pointer to reference the wrapped name. 2518 */ 2519 wsn.wsn_name = name; 2520 if ((*name == '_') && 2521 (strncmp(name, MSG_ORIG(MSG_STR_UU_REAL_U), 2522 MSG_STR_UU_REAL_U_SIZE) == 0)) 2523 wsn.wsn_name += MSG_STR_UU_REAL_U_SIZE; 2524 2525 /* 2526 * Is this symbol in the wrap AVL tree? If so, map 2527 * XXX to __wrap_XXX, and __real_XXX to XXX. Note that 2528 * wsn.wsn_name will equal the current value of name 2529 * if the __real_ prefix is not present. 2530 */ 2531 if ((wsnp = avl_find(ofl->ofl_wrap, &wsn, 0)) != NULL) { 2532 const char *old_name = name; 2533 2534 name = (wsn.wsn_name == name) ? 2535 wsnp->wsn_wrapname : wsn.wsn_name; 2536 DBG_CALL(Dbg_syms_wrap(ofl->ofl_lml, ndx, 2537 old_name, name)); 2538 } 2539 } 2540 2541 /* 2542 * Determine and validate the symbols binding. 2543 */ 2544 bind = ELF_ST_BIND(nsym->st_info); 2545 if ((bind != STB_GLOBAL) && (bind != STB_WEAK)) { 2546 ld_eprintf(ofl, ERR_WARNING, MSG_INTL(MSG_SYM_NONGLOB), 2547 demangle_symname(name, symsecname, ndx), 2548 ifl->ifl_name, 2549 conv_sym_info_bind(bind, 0, &inv_buf)); 2550 continue; 2551 } 2552 if (bind == STB_WEAK) 2553 weak++; 2554 2555 /* 2556 * If this symbol falls within the range of a section being 2557 * discarded, then discard the symbol itself. 2558 */ 2559 if (((sdflags & FLG_SY_SPECSEC) == 0) && 2560 (nsym->st_shndx != SHN_UNDEF)) { 2561 Is_desc *isp; 2562 2563 if (shndx >= ifl->ifl_shnum) { 2564 /* 2565 * Carry our some basic sanity checks 2566 * The symbol will not be carried forward to 2567 * the output file, which won't be a problem 2568 * unless a relocation is required against it. 2569 */ 2570 ld_eprintf(ofl, ERR_WARNING, 2571 MSG_INTL(MSG_SYM_INVSHNDX), 2572 demangle_symname(name, symsecname, ndx), 2573 ifl->ifl_name, 2574 conv_sym_shndx(osabi, mach, nsym->st_shndx, 2575 CONV_FMT_DECIMAL, &inv_buf)); 2576 continue; 2577 } 2578 2579 isp = ifl->ifl_isdesc[shndx]; 2580 if (isp && (isp->is_flags & FLG_IS_DISCARD)) { 2581 if ((sdp = 2582 libld_calloc(sizeof (Sym_desc), 1)) == NULL) 2583 return (S_ERROR); 2584 2585 /* 2586 * Create a dummy symbol entry so that if we 2587 * find any references to this discarded symbol 2588 * we can compensate. 2589 */ 2590 sdp->sd_name = name; 2591 sdp->sd_sym = nsym; 2592 sdp->sd_file = ifl; 2593 sdp->sd_isc = isp; 2594 sdp->sd_flags = FLG_SY_ISDISC; 2595 ifl->ifl_oldndx[ndx] = sdp; 2596 2597 DBG_CALL(Dbg_syms_discarded(ofl->ofl_lml, sdp)); 2598 continue; 2599 } 2600 } 2601 2602 /* 2603 * If object capabilities for this file are being converted 2604 * into symbol capabilities, then: 2605 * 2606 * - Any global function, or initialized global data symbol 2607 * definitions (ie., those that are not associated with 2608 * special symbol types, ie., ABS, COMMON, etc.), and which 2609 * have not been reduced to locals, are converted to symbol 2610 * references (UNDEF). This ensures that any reference to 2611 * the original symbol, for example from a relocation, get 2612 * associated to a capabilities family lead symbol, ie., a 2613 * generic instance. 2614 * 2615 * - For each global function, or object symbol definition, 2616 * a new local symbol is created. The function or object 2617 * is renamed using the capabilities CA_SUNW_ID definition 2618 * (which might have been fabricated for this purpose - 2619 * see get_cap_group()). The new symbol name is: 2620 * 2621 * <original name>%<capability group identifier> 2622 * 2623 * This symbol is associated to the same location, and 2624 * becomes a capabilities family member. 2625 */ 2626 /* LINTED */ 2627 hash = (Word)elf_hash(name); 2628 2629 ntype = ELF_ST_TYPE(nsym->st_info); 2630 if (cdp && (nsym->st_shndx != SHN_UNDEF) && 2631 ((sdflags & FLG_SY_SPECSEC) == 0) && 2632 ((ntype == STT_FUNC) || (ntype == STT_OBJECT))) { 2633 /* 2634 * Determine this symbol's visibility. If a mapfile has 2635 * indicated this symbol should be local, then there's 2636 * no point in transforming this global symbol to a 2637 * capabilities symbol. Otherwise, create a symbol 2638 * capability pair descriptor to record this symbol as 2639 * a candidate for translation. 2640 */ 2641 if (sym_cap_vis(name, hash, sym, ofl) && 2642 ((cpp = alist_append(&cappairs, NULL, 2643 sizeof (Cap_pair), AL_CNT_CAP_PAIRS)) == NULL)) 2644 return (S_ERROR); 2645 } 2646 2647 if (cpp) { 2648 Sym *rsym; 2649 2650 DBG_CALL(Dbg_syms_cap_convert(ofl, ndx, name, nsym)); 2651 2652 /* 2653 * Allocate a new symbol descriptor to represent the 2654 * transformed global symbol. The descriptor points 2655 * to the original symbol information (which might 2656 * indicate a global or weak visibility). The symbol 2657 * information will be transformed into a local symbol 2658 * later, after any weak aliases are culled. 2659 */ 2660 if ((cpp->c_osdp = 2661 libld_malloc(sizeof (Sym_desc))) == NULL) 2662 return (S_ERROR); 2663 2664 cpp->c_osdp->sd_name = name; 2665 cpp->c_osdp->sd_sym = nsym; 2666 cpp->c_osdp->sd_shndx = shndx; 2667 cpp->c_osdp->sd_file = ifl; 2668 cpp->c_osdp->sd_isc = ifl->ifl_isdesc[shndx]; 2669 cpp->c_osdp->sd_ref = REF_REL_NEED; 2670 2671 /* 2672 * Save the capabilities group this symbol belongs to, 2673 * and the original symbol index. 2674 */ 2675 cpp->c_group = cdp->ca_groups->apl_data[0]; 2676 cpp->c_ndx = ndx; 2677 2678 /* 2679 * Replace the original symbol definition with a symbol 2680 * reference. Make sure this reference isn't left as a 2681 * weak. 2682 */ 2683 if ((rsym = libld_malloc(sizeof (Sym))) == NULL) 2684 return (S_ERROR); 2685 2686 *rsym = *nsym; 2687 2688 rsym->st_info = ELF_ST_INFO(STB_GLOBAL, ntype); 2689 rsym->st_shndx = shndx = SHN_UNDEF; 2690 rsym->st_value = 0; 2691 rsym->st_size = 0; 2692 2693 sdflags |= FLG_SY_CAP; 2694 2695 nsym = rsym; 2696 } 2697 2698 /* 2699 * If the symbol does not already exist in the internal symbol 2700 * table add it, otherwise resolve the conflict. If the symbol 2701 * from this file is kept, retain its symbol table index for 2702 * possible use in associating a global alias. 2703 */ 2704 if ((sdp = ld_sym_find(name, hash, &where, ofl)) == NULL) { 2705 DBG_CALL(Dbg_syms_global(ofl->ofl_lml, ndx, name)); 2706 if ((sdp = ld_sym_enter(name, nsym, hash, ifl, ofl, ndx, 2707 shndx, sdflags, &where)) == (Sym_desc *)S_ERROR) 2708 return (S_ERROR); 2709 2710 } else if (ld_sym_resolve(sdp, nsym, ifl, ofl, ndx, shndx, 2711 sdflags) == S_ERROR) 2712 return (S_ERROR); 2713 2714 /* 2715 * Now that we have a symbol descriptor, retain the descriptor 2716 * for later use by symbol capabilities processing. 2717 */ 2718 if (cpp) 2719 cpp->c_nsdp = sdp; 2720 2721 /* 2722 * After we've compared a defined symbol in one shared 2723 * object, flag the symbol so we don't compare it again. 2724 */ 2725 if ((etype == ET_DYN) && (nsym->st_shndx != SHN_UNDEF) && 2726 ((sdp->sd_flags & FLG_SY_SOFOUND) == 0)) 2727 sdp->sd_flags |= FLG_SY_SOFOUND; 2728 2729 /* 2730 * If the symbol is accepted from this file retain the symbol 2731 * index for possible use in aliasing. 2732 */ 2733 if (sdp->sd_file == ifl) 2734 sdp->sd_symndx = ndx; 2735 2736 ifl->ifl_oldndx[ndx] = sdp; 2737 2738 /* 2739 * If we've accepted a register symbol, continue to validate 2740 * it. 2741 */ 2742 if (sdp->sd_flags & FLG_SY_REGSYM) { 2743 Sym_desc *rsdp; 2744 2745 /* 2746 * The presence of FLG_SY_REGSYM means that 2747 * the pointers in ld_targ.t_ms are non-NULL. 2748 */ 2749 rsdp = (*ld_targ.t_ms.ms_reg_find)(sdp->sd_sym, ofl); 2750 if (rsdp == NULL) { 2751 if ((*ld_targ.t_ms.ms_reg_enter)(sdp, ofl) == 0) 2752 return (S_ERROR); 2753 } else if (rsdp != sdp) { 2754 (void) (*ld_targ.t_ms.ms_reg_check)(rsdp, 2755 sdp->sd_sym, sdp->sd_name, ifl, ofl); 2756 } 2757 } 2758 2759 /* 2760 * For a relocatable object, if this symbol is defined 2761 * and has non-zero length and references an address 2762 * within an associated section, then check its extents 2763 * to make sure the section boundaries encompass it. 2764 * If they don't, the ELF file is corrupt. Note that this 2765 * global symbol may have come from another file to satisfy 2766 * an UNDEF symbol of the same name from this one. In that 2767 * case, we don't check it, because it was already checked 2768 * as part of its own file. 2769 */ 2770 if (etype_rel && (sdp->sd_file == ifl)) { 2771 Sym *tsym = sdp->sd_sym; 2772 2773 if (SYM_LOC_BADADDR(sdp, tsym, 2774 ELF_ST_TYPE(tsym->st_info))) { 2775 issue_badaddr_msg(ifl, ofl, sdp, 2776 tsym, tsym->st_shndx); 2777 continue; 2778 } 2779 } 2780 } 2781 DBG_CALL(Dbg_util_nl(ofl->ofl_lml, DBG_NL_STD)); 2782 2783 /* 2784 * Associate weak (alias) symbols to their non-weak counterparts by 2785 * scanning the global symbols one more time. 2786 * 2787 * This association is needed when processing the symbols from a shared 2788 * object dependency when a a weak definition satisfies a reference: 2789 * 2790 * - When building a dynamic executable, if a referenced symbol is a 2791 * data item, the symbol data is copied to the executables address 2792 * space. In this copy-relocation case, we must also reassociate 2793 * the alias symbol with its new location in the executable. 2794 * 2795 * - If the referenced symbol is a function then we may need to 2796 * promote the symbols binding from undefined weak to undefined, 2797 * otherwise the run-time linker will not generate the correct 2798 * relocation error should the symbol not be found. 2799 * 2800 * Weak alias association is also required when a local dynsym table 2801 * is being created. This table should only contain one instance of a 2802 * symbol that is associated to a given address. 2803 * 2804 * The true association between a weak/strong symbol pair is that both 2805 * symbol entries are identical, thus first we create a sorted symbol 2806 * list keyed off of the symbols section index and value. If the symbol 2807 * belongs to the same section and has the same value, then the chances 2808 * are that the rest of the symbols data is the same. This list is then 2809 * scanned for weak symbols, and if one is found then any strong 2810 * association will exist in the entries that follow. Thus we just have 2811 * to scan one (typically a single alias) or more (in the uncommon 2812 * instance of multiple weak to strong associations) entries to 2813 * determine if a match exists. 2814 */ 2815 if (weak && (OFL_ALLOW_LDYNSYM(ofl) || (etype == ET_DYN)) && 2816 (total > local)) { 2817 static Sym_desc **sort; 2818 static size_t osize = 0; 2819 size_t nsize = (total - local) * sizeof (Sym_desc *); 2820 2821 /* 2822 * As we might be processing many input files, and many symbols, 2823 * try and reuse a static sort buffer. Note, presently we're 2824 * playing the game of never freeing any buffers as there's a 2825 * belief this wastes time. 2826 */ 2827 if ((osize == 0) || (nsize > osize)) { 2828 if ((sort = libld_malloc(nsize)) == NULL) 2829 return (S_ERROR); 2830 osize = nsize; 2831 } 2832 (void) memcpy((void *)sort, &ifl->ifl_oldndx[local], nsize); 2833 2834 qsort(sort, (total - local), sizeof (Sym_desc *), compare); 2835 2836 for (ndx = 0; ndx < (total - local); ndx++) { 2837 Sym_desc *wsdp = sort[ndx]; 2838 Sym *wsym; 2839 int sndx; 2840 2841 /* 2842 * Ignore any empty symbol descriptor, or the case where 2843 * the symbol has been resolved to a different file. 2844 */ 2845 if ((wsdp == NULL) || (wsdp->sd_file != ifl)) 2846 continue; 2847 2848 wsym = wsdp->sd_sym; 2849 2850 if ((wsym->st_shndx == SHN_UNDEF) || 2851 (wsdp->sd_flags & FLG_SY_SPECSEC) || 2852 (ELF_ST_BIND(wsym->st_info) != STB_WEAK)) 2853 continue; 2854 2855 /* 2856 * We have a weak symbol, if it has a strong alias it 2857 * will have been sorted to one of the following sort 2858 * table entries. Note that we could have multiple weak 2859 * symbols aliased to one strong (if this occurs then 2860 * the strong symbol only maintains one alias back to 2861 * the last weak). 2862 */ 2863 for (sndx = ndx + 1; sndx < (total - local); sndx++) { 2864 Sym_desc *ssdp = sort[sndx]; 2865 Sym *ssym; 2866 sd_flag_t w_dynbits, s_dynbits; 2867 2868 /* 2869 * Ignore any empty symbol descriptor, or the 2870 * case where the symbol has been resolved to a 2871 * different file. 2872 */ 2873 if ((ssdp == NULL) || (ssdp->sd_file != ifl)) 2874 continue; 2875 2876 ssym = ssdp->sd_sym; 2877 2878 if (ssym->st_shndx == SHN_UNDEF) 2879 continue; 2880 2881 if ((ssym->st_shndx != wsym->st_shndx) || 2882 (ssym->st_value != wsym->st_value)) 2883 break; 2884 2885 if ((ssym->st_size != wsym->st_size) || 2886 (ssdp->sd_flags & FLG_SY_SPECSEC) || 2887 (ELF_ST_BIND(ssym->st_info) == STB_WEAK)) 2888 continue; 2889 2890 /* 2891 * If a sharable object, set link fields so 2892 * that they reference each other.` 2893 */ 2894 if (etype == ET_DYN) { 2895 ssdp->sd_aux->sa_linkndx = 2896 (Word)wsdp->sd_symndx; 2897 wsdp->sd_aux->sa_linkndx = 2898 (Word)ssdp->sd_symndx; 2899 } 2900 2901 /* 2902 * Determine which of these two symbols go into 2903 * the sort section. If a mapfile has made 2904 * explicit settings of the FLG_SY_*DYNSORT 2905 * flags for both symbols, then we do what they 2906 * say. If one has the DYNSORT flags set, we 2907 * set the NODYNSORT bit in the other. And if 2908 * neither has an explicit setting, then we 2909 * favor the weak symbol because they usually 2910 * lack the leading underscore. 2911 */ 2912 w_dynbits = wsdp->sd_flags & 2913 (FLG_SY_DYNSORT | FLG_SY_NODYNSORT); 2914 s_dynbits = ssdp->sd_flags & 2915 (FLG_SY_DYNSORT | FLG_SY_NODYNSORT); 2916 if (!(w_dynbits && s_dynbits)) { 2917 if (s_dynbits) { 2918 if (s_dynbits == FLG_SY_DYNSORT) 2919 wsdp->sd_flags |= 2920 FLG_SY_NODYNSORT; 2921 } else if (w_dynbits != 2922 FLG_SY_NODYNSORT) { 2923 ssdp->sd_flags |= 2924 FLG_SY_NODYNSORT; 2925 } 2926 } 2927 break; 2928 } 2929 } 2930 } 2931 2932 /* 2933 * Having processed all symbols, under -z symbolcap, reprocess any 2934 * symbols that are being translated from global to locals. The symbol 2935 * pair that has been collected defines the original symbol (c_osdp), 2936 * which will become a local, and the new symbol (c_nsdp), which will 2937 * become a reference (UNDEF) for the original. 2938 * 2939 * Scan these symbol pairs looking for weak symbols, which have non-weak 2940 * aliases. There is no need to translate both of these symbols to 2941 * locals, only the global is necessary. 2942 */ 2943 if (cappairs) { 2944 Aliste idx1; 2945 Cap_pair *cpp1; 2946 2947 for (ALIST_TRAVERSE(cappairs, idx1, cpp1)) { 2948 Sym_desc *sdp1 = cpp1->c_osdp; 2949 Sym *sym1 = sdp1->sd_sym; 2950 uchar_t bind1 = ELF_ST_BIND(sym1->st_info); 2951 Aliste idx2; 2952 Cap_pair *cpp2; 2953 2954 /* 2955 * If this symbol isn't weak, it's capability member is 2956 * retained for the creation of a local symbol. 2957 */ 2958 if (bind1 != STB_WEAK) 2959 continue; 2960 2961 /* 2962 * If this is a weak symbol, traverse the capabilities 2963 * list again to determine if a corresponding non-weak 2964 * symbol exists. 2965 */ 2966 for (ALIST_TRAVERSE(cappairs, idx2, cpp2)) { 2967 Sym_desc *sdp2 = cpp2->c_osdp; 2968 Sym *sym2 = sdp2->sd_sym; 2969 uchar_t bind2 = 2970 ELF_ST_BIND(sym2->st_info); 2971 2972 if ((cpp1 == cpp2) || 2973 (cpp1->c_group != cpp2->c_group) || 2974 (sym1->st_value != sym2->st_value) || 2975 (bind2 == STB_WEAK)) 2976 continue; 2977 2978 /* 2979 * The weak symbol (sym1) has a non-weak (sym2) 2980 * counterpart. There's no point in translating 2981 * both of these equivalent symbols to locals. 2982 * Add this symbol capability alias to the 2983 * capabilities family information, and remove 2984 * the weak symbol. 2985 */ 2986 if (ld_cap_add_family(ofl, cpp2->c_nsdp, 2987 cpp1->c_nsdp, NULL, NULL) == S_ERROR) 2988 return (S_ERROR); 2989 2990 free((void *)cpp1->c_osdp); 2991 (void) alist_delete(cappairs, &idx1); 2992 } 2993 } 2994 2995 DBG_CALL(Dbg_util_nl(ofl->ofl_lml, DBG_NL_STD)); 2996 2997 /* 2998 * The capability pairs information now represents all the 2999 * global symbols that need transforming to locals. These 3000 * local symbols are renamed using their group identifiers. 3001 */ 3002 for (ALIST_TRAVERSE(cappairs, idx1, cpp1)) { 3003 Sym_desc *osdp = cpp1->c_osdp; 3004 Objcapset *capset; 3005 size_t nsize, tsize; 3006 const char *oname; 3007 char *cname, *idstr; 3008 Sym *csym; 3009 3010 /* 3011 * If the local symbol has not yet been translated 3012 * convert it to a local symbol with a name. 3013 */ 3014 if ((osdp->sd_flags & FLG_SY_CAP) != 0) 3015 continue; 3016 3017 /* 3018 * As we're converting object capabilities to symbol 3019 * capabilities, obtain the capabilities set for this 3020 * object, so as to retrieve the CA_SUNW_ID value. 3021 */ 3022 capset = &cpp1->c_group->cg_set; 3023 3024 /* 3025 * Create a new name from the existing symbol and the 3026 * capabilities group identifier. Note, the delimiter 3027 * between the symbol name and identifier name is hard- 3028 * coded here (%), so that we establish a convention 3029 * for transformed symbol names. 3030 */ 3031 oname = osdp->sd_name; 3032 3033 idstr = capset->oc_id.cs_str; 3034 nsize = strlen(oname); 3035 tsize = nsize + 1 + strlen(idstr) + 1; 3036 if ((cname = libld_malloc(tsize)) == 0) 3037 return (S_ERROR); 3038 3039 (void) strcpy(cname, oname); 3040 cname[nsize++] = '%'; 3041 (void) strcpy(&cname[nsize], idstr); 3042 3043 /* 3044 * Allocate a new symbol table entry, transform this 3045 * symbol to a local, and assign the new name. 3046 */ 3047 if ((csym = libld_malloc(sizeof (Sym))) == NULL) 3048 return (S_ERROR); 3049 3050 *csym = *osdp->sd_sym; 3051 csym->st_info = ELF_ST_INFO(STB_LOCAL, 3052 ELF_ST_TYPE(osdp->sd_sym->st_info)); 3053 3054 osdp->sd_name = cname; 3055 osdp->sd_sym = csym; 3056 osdp->sd_flags = FLG_SY_CAP; 3057 3058 /* 3059 * Keep track of this new local symbol. As -z symbolcap 3060 * can only be used to create a relocatable object, a 3061 * dynamic symbol table can't exist. Ensure there is 3062 * space reserved in the string table. 3063 */ 3064 ofl->ofl_caploclcnt++; 3065 if (st_insert(ofl->ofl_strtab, cname) == -1) 3066 return (S_ERROR); 3067 3068 DBG_CALL(Dbg_syms_cap_local(ofl, cpp1->c_ndx, 3069 cname, csym, osdp)); 3070 3071 /* 3072 * Establish this capability pair as a family. 3073 */ 3074 if (ld_cap_add_family(ofl, cpp1->c_nsdp, osdp, 3075 cpp1->c_group, &ifl->ifl_caps->ca_syms) == S_ERROR) 3076 return (S_ERROR); 3077 } 3078 } 3079 3080 return (1); 3081 3082 #undef SYM_LOC_BADADDR 3083 } 3084 3085 /* 3086 * Add an undefined symbol to the symbol table. The reference originates from 3087 * the location identified by the message id (mid). These references can 3088 * originate from command line options such as -e, -u, -initarray, etc. 3089 * (identified with MSG_INTL(MSG_STR_COMMAND)), or from internally generated 3090 * TLS relocation references (identified with MSG_INTL(MSG_STR_TLSREL)). 3091 */ 3092 Sym_desc * 3093 ld_sym_add_u(const char *name, Ofl_desc *ofl, Msg mid) 3094 { 3095 Sym *sym; 3096 Ifl_desc *ifl = NULL, *_ifl; 3097 Sym_desc *sdp; 3098 Word hash; 3099 Aliste idx; 3100 avl_index_t where; 3101 const char *reference = MSG_INTL(mid); 3102 3103 /* 3104 * As an optimization, determine whether we've already generated this 3105 * reference. If the symbol doesn't already exist we'll create it. 3106 * Or if the symbol does exist from a different source, we'll resolve 3107 * the conflict. 3108 */ 3109 /* LINTED */ 3110 hash = (Word)elf_hash(name); 3111 if ((sdp = ld_sym_find(name, hash, &where, ofl)) != NULL) { 3112 if ((sdp->sd_sym->st_shndx == SHN_UNDEF) && 3113 (sdp->sd_file->ifl_name == reference)) 3114 return (sdp); 3115 } 3116 3117 /* 3118 * Determine whether a pseudo input file descriptor exists to represent 3119 * the command line, as any global symbol needs an input file descriptor 3120 * during any symbol resolution (refer to map_ifl() which provides a 3121 * similar method for adding symbols from mapfiles). 3122 */ 3123 for (APLIST_TRAVERSE(ofl->ofl_objs, idx, _ifl)) 3124 if (strcmp(_ifl->ifl_name, reference) == 0) { 3125 ifl = _ifl; 3126 break; 3127 } 3128 3129 /* 3130 * If no descriptor exists create one. 3131 */ 3132 if (ifl == NULL) { 3133 if ((ifl = libld_calloc(sizeof (Ifl_desc), 1)) == NULL) 3134 return ((Sym_desc *)S_ERROR); 3135 ifl->ifl_name = reference; 3136 ifl->ifl_flags = FLG_IF_NEEDED | FLG_IF_FILEREF; 3137 if ((ifl->ifl_ehdr = libld_calloc(sizeof (Ehdr), 1)) == NULL) 3138 return ((Sym_desc *)S_ERROR); 3139 ifl->ifl_ehdr->e_type = ET_REL; 3140 3141 if (aplist_append(&ofl->ofl_objs, ifl, AL_CNT_OFL_OBJS) == NULL) 3142 return ((Sym_desc *)S_ERROR); 3143 } 3144 3145 /* 3146 * Allocate a symbol structure and add it to the global symbol table. 3147 */ 3148 if ((sym = libld_calloc(sizeof (Sym), 1)) == NULL) 3149 return ((Sym_desc *)S_ERROR); 3150 sym->st_info = ELF_ST_INFO(STB_GLOBAL, STT_NOTYPE); 3151 sym->st_shndx = SHN_UNDEF; 3152 3153 DBG_CALL(Dbg_syms_process(ofl->ofl_lml, ifl)); 3154 if (sdp == NULL) { 3155 DBG_CALL(Dbg_syms_global(ofl->ofl_lml, 0, name)); 3156 if ((sdp = ld_sym_enter(name, sym, hash, ifl, ofl, 0, SHN_UNDEF, 3157 0, &where)) == (Sym_desc *)S_ERROR) 3158 return ((Sym_desc *)S_ERROR); 3159 } else if (ld_sym_resolve(sdp, sym, ifl, ofl, 0, 3160 SHN_UNDEF, 0) == S_ERROR) 3161 return ((Sym_desc *)S_ERROR); 3162 3163 sdp->sd_flags &= ~FLG_SY_CLEAN; 3164 sdp->sd_flags |= FLG_SY_CMDREF; 3165 3166 return (sdp); 3167 } 3168 3169 /* 3170 * STT_SECTION symbols have their st_name field set to NULL, and consequently 3171 * have no name. Generate a name suitable for diagnostic use for such a symbol 3172 * and store it in the input section descriptor. The resulting name will be 3173 * of the form: 3174 * 3175 * "XXX (section)" 3176 * 3177 * where XXX is the name of the section. 3178 * 3179 * entry: 3180 * isc - Input section associated with the symbol. 3181 * fmt - NULL, or format string to use. 3182 * 3183 * exit: 3184 * Sets isp->is_sym_name to the allocated string. Returns the 3185 * string pointer, or NULL on allocation failure. 3186 */ 3187 const char * 3188 ld_stt_section_sym_name(Is_desc *isp) 3189 { 3190 const char *fmt; 3191 char *str; 3192 size_t len; 3193 3194 if ((isp == NULL) || (isp->is_name == NULL)) 3195 return (NULL); 3196 3197 if (isp->is_sym_name == NULL) { 3198 fmt = (isp->is_flags & FLG_IS_GNSTRMRG) ? 3199 MSG_INTL(MSG_STR_SECTION_MSTR) : MSG_INTL(MSG_STR_SECTION); 3200 3201 len = strlen(fmt) + strlen(isp->is_name) + 1; 3202 3203 if ((str = libld_malloc(len)) == NULL) 3204 return (NULL); 3205 (void) snprintf(str, len, fmt, isp->is_name); 3206 isp->is_sym_name = str; 3207 } 3208 3209 return (isp->is_sym_name); 3210 }