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 2006 Sun Microsystems, Inc. All rights reserved. 28 * Use is subject to license terms. 29 */ 30 #pragma ident "%Z%%M% %I% %E% SMI" 31 32 /* 33 * Symbol table management routines 34 */ 35 #include <stdio.h> 36 #include <string.h> 37 #include <debug.h> 38 #include "msg.h" 39 #include "_libld.h" 40 41 /* 42 * AVL tree comparator function: 43 * 44 * The primary key is the 'sa_hashval' with a secondary 45 * key of the symbol name itself. 46 */ 47 int 48 ld_sym_avl_comp(const void *elem1, const void *elem2) 49 { 50 int res; 51 Sym_avlnode *sav1 = (Sym_avlnode *)elem1; 52 Sym_avlnode *sav2 = (Sym_avlnode *)elem2; 53 54 res = sav1->sav_hash - sav2->sav_hash; 55 56 if (res < 0) 57 return (-1); 58 if (res > 0) 59 return (1); 60 61 /* 62 * Hash is equal - now compare name 63 */ 64 res = strcmp(sav1->sav_name, sav2->sav_name); 65 if (res == 0) 66 return (0); 67 if (res > 0) 68 return (1); 69 return (-1); 70 } 71 72 73 /* 74 * Focal point for verifying symbol names. 75 */ 76 static const char * 77 string(Ofl_desc *ofl, Ifl_desc *ifl, Sym *sym, const char *strs, size_t strsize, 78 int symndx, Word shndx, const char *symsecname, const char *strsecname, 79 Word *flags) 80 { 81 const char *regname; 82 Word name = sym->st_name; 83 84 if (name) { 85 if ((ifl->ifl_flags & FLG_IF_HSTRTAB) == 0) { 86 eprintf(ofl->ofl_lml, ERR_FATAL, 87 MSG_INTL(MSG_FIL_NOSTRTABLE), ifl->ifl_name, 88 symsecname, symndx, EC_XWORD(name)); 89 return (0); 90 } 91 if (name >= (Word)strsize) { 92 eprintf(ofl->ofl_lml, ERR_FATAL, 93 MSG_INTL(MSG_FIL_EXCSTRTABLE), ifl->ifl_name, 94 symsecname, symndx, EC_XWORD(name), 95 strsecname, EC_XWORD(strsize)); 96 return (0); 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 ((regname = ld_is_regsym(ofl, ifl, sym, strs, symndx, shndx, 105 symsecname, flags)) == (const char *)S_ERROR) { 106 return (0); 107 } 108 if (regname) 109 return (regname); 110 111 /* 112 * If this isn't a register, but we have a global symbol with a null 113 * name, we're not going to be able to hash this, search for it, or 114 * do anything interesting. However, we've been accepting a symbol of 115 * this kind for ages now, so give the user a warning (rather than a 116 * fatal error), just in case this instance exists somewhere in the 117 * world and hasn't, as yet, been a problem. 118 */ 119 if ((name == 0) && (ELF_ST_BIND(sym->st_info) != STB_LOCAL)) { 120 eprintf(ofl->ofl_lml, ERR_WARNING, MSG_INTL(MSG_FIL_NONAMESYM), 121 ifl->ifl_name, symsecname, symndx, EC_XWORD(name)); 122 } 123 return (strs + name); 124 } 125 126 /* 127 * Shared objects can be built that define specific symbols that can not be 128 * directly bound to. These objects have a syminfo section (and an associated 129 * DF_1_NODIRECT dynamic flags entry). Scan this table looking for symbols 130 * that can't be bound to directly, and if this files symbol is presently 131 * referenced, mark it so that we don't directly bind to it. 132 */ 133 uintptr_t 134 ld_sym_nodirect(Is_desc * isp, Ifl_desc * ifl, Ofl_desc * ofl) 135 { 136 Shdr *sifshdr, *symshdr; 137 Syminfo *sifdata; 138 Sym *symdata; 139 char *strdata; 140 ulong_t cnt, _cnt; 141 142 /* 143 * Get the syminfo data, and determine the number of entries. 144 */ 145 sifshdr = isp->is_shdr; 146 sifdata = (Syminfo *)isp->is_indata->d_buf; 147 cnt = sifshdr->sh_size / sifshdr->sh_entsize; 148 149 /* 150 * Get the associated symbol table. 151 */ 152 symshdr = ifl->ifl_isdesc[sifshdr->sh_link]->is_shdr; 153 symdata = ifl->ifl_isdesc[sifshdr->sh_link]->is_indata->d_buf; 154 155 /* 156 * Get the string table associated with the symbol table. 157 */ 158 strdata = ifl->ifl_isdesc[symshdr->sh_link]->is_indata->d_buf; 159 160 /* 161 * Traverse the syminfo data for symbols that can't be directly 162 * bound to. 163 */ 164 for (_cnt = 1, sifdata++; _cnt < cnt; _cnt++, sifdata++) { 165 Sym *sym; 166 char *str; 167 Sym_desc *sdp; 168 169 if (((sifdata->si_flags & SYMINFO_FLG_NOEXTDIRECT) == 0) || 170 (sifdata->si_boundto < SYMINFO_BT_LOWRESERVE)) 171 continue; 172 173 sym = (Sym *)(symdata + _cnt); 174 str = (char *)(strdata + sym->st_name); 175 176 if (sdp = ld_sym_find(str, SYM_NOHASH, 0, ofl)) { 177 if (ifl != sdp->sd_file) 178 continue; 179 180 sdp->sd_flags1 &= ~FLG_SY1_DIR; 181 sdp->sd_flags1 |= FLG_SY1_NDIR; 182 } 183 } 184 return (0); 185 } 186 187 /* 188 * If, during symbol processing, it is necessary to update a local symbols 189 * contents before we have generated the symbol tables in the output image, 190 * create a new symbol structure and copy the original symbol contents. While 191 * we are processing the input files, their local symbols are part of the 192 * read-only mapped image. Commonly, these symbols are copied to the new output 193 * file image and then updated to reflect their new address and any change in 194 * attributes. However, sometimes during relocation counting, it is necessary 195 * to adjust the symbols information. This routine provides for the generation 196 * of a new symbol image so that this update can be performed. 197 * All global symbols are copied to an internal symbol table to improve locality 198 * of reference and hence performance, and thus this copying is not necessary. 199 */ 200 uintptr_t 201 ld_sym_copy(Sym_desc *sdp) 202 { 203 Sym *nsym; 204 205 if (sdp->sd_flags & FLG_SY_CLEAN) { 206 if ((nsym = libld_malloc(sizeof (Sym))) == 0) 207 return (S_ERROR); 208 *nsym = *(sdp->sd_sym); 209 sdp->sd_sym = nsym; 210 sdp->sd_flags &= ~FLG_SY_CLEAN; 211 } 212 return (1); 213 } 214 215 /* 216 * Finds a given name in the link editors internal symbol table. If no 217 * hash value is specified it is calculated. A pointer to the located 218 * Sym_desc entry is returned, or NULL if the symbol is not found. 219 */ 220 Sym_desc * 221 ld_sym_find(const char *name, Word hash, avl_index_t *where, Ofl_desc *ofl) 222 { 223 Sym_avlnode qsav; 224 Sym_avlnode *sav; 225 226 if (hash == SYM_NOHASH) 227 /* LINTED */ 228 hash = (Word)elf_hash((const char *)name); 229 qsav.sav_hash = hash; 230 qsav.sav_name = name; 231 232 /* 233 * Perform search for symbol in AVL tree. Note that the 'where' field 234 * is passed in from the caller. If a 'where' is present, it can be 235 * used in subsequent 'sym_enter()' calls if required. 236 */ 237 sav = avl_find(&ofl->ofl_symavl, &qsav, where); 238 239 /* 240 * If symbol was not found in the avl tree, return null to show that. 241 */ 242 if (sav == 0) 243 return (0); 244 245 /* 246 * Return symbol found. 247 */ 248 return (sav->sav_symdesc); 249 } 250 251 252 /* 253 * Enter a new symbol into the link editors internal symbol table. 254 * If the symbol is from an input file, information regarding the input file 255 * and input section is also recorded. Otherwise (file == NULL) the symbol 256 * has been internally generated (ie. _etext, _edata, etc.). 257 */ 258 Sym_desc * 259 ld_sym_enter(const char *name, Sym *osym, Word hash, Ifl_desc *ifl, 260 Ofl_desc *ofl, Word ndx, Word shndx, Word sdflags, Half sdflags1, 261 avl_index_t *where) 262 { 263 Sym_desc *sdp; 264 Sym_aux *sap; 265 Sym_avlnode *savl; 266 char *_name; 267 Sym *nsym; 268 Half etype; 269 avl_index_t _where; 270 271 /* 272 * Establish the file type. 273 */ 274 if (ifl) 275 etype = ifl->ifl_ehdr->e_type; 276 else 277 etype = ET_NONE; 278 279 ofl->ofl_entercnt++; 280 281 /* 282 * Allocate a Sym Descriptor, Auxiliary Descriptor, and a Sym AVLNode - 283 * contiguously. 284 */ 285 if ((savl = libld_calloc(sizeof (Sym_avlnode) + sizeof (Sym_desc) + 286 sizeof (Sym_aux), 1)) == 0) 287 return ((Sym_desc *)S_ERROR); 288 sdp = (Sym_desc *)((uintptr_t)savl + sizeof (Sym_avlnode)); 289 sap = (Sym_aux *)((uintptr_t)sdp + sizeof (Sym_desc)); 290 291 savl->sav_symdesc = sdp; 292 sdp->sd_file = ifl; 293 sdp->sd_aux = sap; 294 savl->sav_hash = sap->sa_hash = hash; 295 296 297 /* 298 * Copy the symbol table entry from the input file into the internal 299 * entry and have the symbol descriptor use it. 300 */ 301 sdp->sd_sym = nsym = &sap->sa_sym; 302 *nsym = *osym; 303 sdp->sd_shndx = shndx; 304 sdp->sd_flags |= sdflags; 305 sdp->sd_flags1 |= sdflags1; 306 307 if ((_name = libld_malloc(strlen(name) + 1)) == 0) 308 return ((Sym_desc *)S_ERROR); 309 savl->sav_name = sdp->sd_name = (const char *)strcpy(_name, name); 310 311 /* 312 * Enter Symbol in AVL tree. 313 */ 314 if (where == 0) { 315 /* LINTED */ 316 Sym_avlnode *_savl; 317 /* 318 * If a previous ld_sym_find() hasn't initialized 'where' do it 319 * now. 320 */ 321 where = &_where; 322 _savl = avl_find(&ofl->ofl_symavl, savl, where); 323 assert(_savl == 0); 324 } 325 avl_insert(&ofl->ofl_symavl, savl, *where); 326 327 /* 328 * Record the section index. This is possible because the 329 * `ifl_isdesc' table is filled before we start symbol processing. 330 */ 331 if ((sdflags & FLG_SY_SPECSEC) || (nsym->st_shndx == SHN_UNDEF)) 332 sdp->sd_isc = NULL; 333 else { 334 sdp->sd_isc = ifl->ifl_isdesc[shndx]; 335 336 /* 337 * If this symbol is from a relocatable object, make sure that 338 * it is still associated with a section. For example, an 339 * unknown section type (SHT_NULL) would have been rejected on 340 * input with a warning. Here, we make the use of the symbol 341 * fatal. A symbol descriptor is still returned, so that the 342 * caller can continue processing all symbols, and hence flush 343 * out as many error conditions as possible. 344 */ 345 if ((etype == ET_REL) && (sdp->sd_isc == 0)) { 346 eprintf(ofl->ofl_lml, ERR_FATAL, 347 MSG_INTL(MSG_SYM_INVSEC), name, ifl->ifl_name, 348 EC_XWORD(shndx)); 349 ofl->ofl_flags |= FLG_OF_FATAL; 350 return (sdp); 351 } 352 } 353 354 /* 355 * Mark any COMMON symbols as 'tentative'. 356 */ 357 if (sdflags & FLG_SY_SPECSEC) { 358 if (nsym->st_shndx == SHN_COMMON) 359 sdp->sd_flags |= FLG_SY_TENTSYM; 360 #if (defined(__i386) || defined(__amd64)) && defined(_ELF64) 361 else if (nsym->st_shndx == SHN_X86_64_LCOMMON) 362 sdp->sd_flags |= FLG_SY_TENTSYM; 363 #endif 364 } 365 366 /* 367 * Establish the symbols reference & visibility. 368 */ 369 if ((etype == ET_NONE) || (etype == ET_REL)) { 370 sdp->sd_ref = REF_REL_NEED; 371 372 /* 373 * Under -Bnodirect, all exported interfaces are tagged to 374 * prevent direct binding to them. 375 */ 376 if ((ofl->ofl_flags1 & FLG_OF1_ALNODIR) && 377 (nsym->st_shndx != SHN_UNDEF)) 378 sdp->sd_flags1 |= FLG_SY1_NDIR; 379 380 } else { 381 sdp->sd_ref = REF_DYN_SEEN; 382 383 /* 384 * Record the binding file for this symbol in the sa_bindto 385 * field. If this symbol is ever overridden by a REF_REL_NEED 386 * definition, sa_bindto is used when building a 'translator'. 387 */ 388 if (nsym->st_shndx != SHN_UNDEF) 389 sdp->sd_aux->sa_bindto = ifl; 390 391 /* 392 * If this is a protected symbol, mark it. 393 */ 394 if (ELF_ST_VISIBILITY(nsym->st_other) == STV_PROTECTED) 395 sdp->sd_flags |= FLG_SY_PROT; 396 397 /* 398 * Mask out any visibility info from a DYN symbol. 399 */ 400 nsym->st_other = nsym->st_other & ~MSK_SYM_VISIBILITY; 401 402 /* 403 * If the new symbol is from a shared library and it 404 * is associated with a SHT_NOBITS section then this 405 * symbol originated from a tentative symbol. 406 */ 407 if (sdp->sd_isc && 408 (sdp->sd_isc->is_shdr->sh_type == SHT_NOBITS)) 409 sdp->sd_flags |= FLG_SY_TENTSYM; 410 } 411 412 /* 413 * Reclassify any SHN_SUNW_IGNORE symbols to SHN_UNDEF so as to 414 * simplify future processing. 415 */ 416 if (nsym->st_shndx == SHN_SUNW_IGNORE) { 417 sdp->sd_shndx = shndx = SHN_UNDEF; 418 sdp->sd_flags |= FLG_SY_REDUCED; 419 sdp->sd_flags1 |= 420 (FLG_SY1_IGNORE | FLG_SY1_LOCL | FLG_SY1_ELIM); 421 } 422 423 /* 424 * If this is an undefined, or common symbol from a relocatable object 425 * determine whether it is a global or weak reference (see build_osym(), 426 * where REF_DYN_NEED definitions are returned back to undefines). 427 */ 428 if ((etype == ET_REL) && 429 (ELF_ST_BIND(nsym->st_info) == STB_GLOBAL) && 430 ((nsym->st_shndx == SHN_UNDEF) || ((sdflags & FLG_SY_SPECSEC) && 431 #if (defined(__i386) || defined(__amd64)) && defined(_ELF64) 432 ((nsym->st_shndx == SHN_COMMON) || 433 (nsym->st_shndx == SHN_X86_64_LCOMMON))))) 434 #else 435 (nsym->st_shndx == SHN_COMMON)))) 436 #endif 437 sdp->sd_flags |= FLG_SY_GLOBREF; 438 439 /* 440 * Record the input filename on the referenced or defined files list 441 * for possible later diagnostics. The `sa_rfile' pointer contains the 442 * name of the file that first referenced this symbol and is used to 443 * generate undefined symbol diagnostics (refer to sym_undef_entry()). 444 * Note that this entry can be overridden if a reference from a 445 * relocatable object is found after a reference from a shared object 446 * (refer to sym_override()). 447 * The `sa_dfiles' list is used to maintain the list of files that 448 * define the same symbol. This list can be used for two reasons: 449 * 450 * o To save the first definition of a symbol that is not available 451 * for this link-edit. 452 * 453 * o To save all definitions of a symbol when the -m option is in 454 * effect. This is optional as it is used to list multiple 455 * (interposed) definitions of a symbol (refer to ldmap_out()), 456 * and can be quite expensive. 457 */ 458 if (nsym->st_shndx == SHN_UNDEF) { 459 sap->sa_rfile = ifl->ifl_name; 460 } else { 461 if (sdp->sd_ref == REF_DYN_SEEN) { 462 /* 463 * A symbol is determined to be unavailable if it 464 * belongs to a version of a shared object that this 465 * user does not wish to use, or if it belongs to an 466 * implicit shared object. 467 */ 468 if (ifl->ifl_vercnt) { 469 Ver_index *vip; 470 Half vndx = ifl->ifl_versym[ndx]; 471 472 sap->sa_dverndx = vndx; 473 vip = &ifl->ifl_verndx[vndx]; 474 if (!(vip->vi_flags & FLG_VER_AVAIL)) { 475 sdp->sd_flags |= FLG_SY_NOTAVAIL; 476 sap->sa_vfile = ifl->ifl_name; 477 } 478 } 479 if (!(ifl->ifl_flags & FLG_IF_NEEDED)) 480 sdp->sd_flags |= FLG_SY_NOTAVAIL; 481 482 } else if (etype == ET_REL) { 483 /* 484 * If this symbol has been obtained from a versioned 485 * input relocatable object then the new symbol must be 486 * promoted to the versioning of the output file. 487 */ 488 if (ifl->ifl_versym) 489 ld_vers_promote(sdp, ndx, ifl, ofl); 490 } 491 492 if ((ofl->ofl_flags & FLG_OF_GENMAP) && 493 ((sdflags & FLG_SY_SPECSEC) == 0)) 494 if (list_appendc(&sap->sa_dfiles, ifl->ifl_name) == 0) 495 return ((Sym_desc *)S_ERROR); 496 } 497 498 DBG_CALL(Dbg_syms_entered(ofl, nsym, sdp)); 499 return (sdp); 500 } 501 502 /* 503 * Add a special symbol to the symbol table. Takes special symbol name with 504 * and without underscores. This routine is called, after all other symbol 505 * resolution has completed, to generate a reserved absolute symbol (the 506 * underscore version). Special symbols are updated with the appropriate 507 * values in update_osym(). If the user has already defined this symbol 508 * issue a warning and leave the symbol as is. If the non-underscore symbol 509 * is referenced then turn it into a weak alias of the underscored symbol. 510 * 511 * If this is a global symbol, and it hasn't explicitly been defined as being 512 * directly bound to, indicate that it can't be directly bound to. 513 * Historically, most special symbols only have meaning to the object in which 514 * they exist, however, they've always been global. To ensure compatibility 515 * with any unexpected use presently in effect, ensure these symbols don't get 516 * directly bound to. Note, that establishing this state here isn't sufficient 517 * to create a syminfo table, only if a syminfo table is being created by some 518 * other symbol directives will the nodirect binding be recorded. This ensures 519 * we don't create syminfo sections for all objects we create, as this might add 520 * unnecessary bloat to users who haven't explicitly requested extra symbol 521 * information. 522 */ 523 static uintptr_t 524 sym_add_spec(const char *name, const char *uname, Word sdaux_id, 525 Half flags1, Ofl_desc *ofl) 526 { 527 Sym_desc *sdp; 528 Sym_desc *usdp; 529 Sym *sym; 530 Word hash; 531 avl_index_t where; 532 533 /* LINTED */ 534 hash = (Word)elf_hash(uname); 535 if (usdp = ld_sym_find(uname, hash, &where, ofl)) { 536 /* 537 * If the underscore symbol exists and is undefined, or was 538 * defined in a shared library, convert it to a local symbol. 539 * Otherwise leave it as is and warn the user. 540 */ 541 if ((usdp->sd_shndx == SHN_UNDEF) || 542 (usdp->sd_ref != REF_REL_NEED)) { 543 usdp->sd_ref = REF_REL_NEED; 544 usdp->sd_shndx = usdp->sd_sym->st_shndx = SHN_ABS; 545 usdp->sd_flags |= FLG_SY_SPECSEC; 546 usdp->sd_sym->st_info = 547 ELF_ST_INFO(STB_GLOBAL, STT_OBJECT); 548 usdp->sd_isc = NULL; 549 usdp->sd_sym->st_size = 0; 550 usdp->sd_sym->st_value = 0; 551 /* LINTED */ 552 usdp->sd_aux->sa_symspec = (Half)sdaux_id; 553 554 /* 555 * If a user hasn't specifically indicated the scope of 556 * this symbol be made local then leave it as global 557 * (ie. prevent automatic scoping). 558 */ 559 if (!(usdp->sd_flags1 & FLG_SY1_LOCL) && 560 (flags1 & FLG_SY1_GLOB)) { 561 usdp->sd_aux->sa_overndx = VER_NDX_GLOBAL; 562 if ((usdp->sd_flags1 & FLG_SY1_DIR) == 0) 563 usdp->sd_flags1 |= FLG_SY1_NDIR; 564 } 565 usdp->sd_flags1 |= flags1; 566 567 /* 568 * If the reference originated from a mapfile ensure 569 * we mark the symbol as used. 570 */ 571 if (usdp->sd_flags & FLG_SY_MAPREF) 572 usdp->sd_flags |= FLG_SY_MAPUSED; 573 574 DBG_CALL(Dbg_syms_updated(ofl, usdp, uname)); 575 } else 576 eprintf(ofl->ofl_lml, ERR_WARNING, 577 MSG_INTL(MSG_SYM_RESERVE), uname, 578 usdp->sd_file->ifl_name); 579 } else { 580 /* 581 * If the symbol does not exist create it. 582 */ 583 if ((sym = libld_calloc(sizeof (Sym), 1)) == 0) 584 return (S_ERROR); 585 sym->st_shndx = SHN_ABS; 586 sym->st_info = ELF_ST_INFO(STB_GLOBAL, STT_OBJECT); 587 sym->st_size = 0; 588 sym->st_value = 0; 589 DBG_CALL(Dbg_syms_created(ofl->ofl_lml, uname)); 590 if ((usdp = ld_sym_enter(uname, sym, hash, (Ifl_desc *)NULL, 591 ofl, 0, SHN_ABS, FLG_SY_SPECSEC, 0, &where)) == 592 (Sym_desc *)S_ERROR) 593 return (S_ERROR); 594 usdp->sd_ref = REF_REL_NEED; 595 /* LINTED */ 596 usdp->sd_aux->sa_symspec = (Half)sdaux_id; 597 598 usdp->sd_aux->sa_overndx = VER_NDX_GLOBAL; 599 if (flags1 & FLG_SY1_GLOB) 600 usdp->sd_flags1 |= FLG_SY1_NDIR; 601 usdp->sd_flags1 |= flags1; 602 } 603 604 if (name && (sdp = ld_sym_find(name, SYM_NOHASH, 0, ofl)) && 605 (sdp->sd_sym->st_shndx == SHN_UNDEF)) { 606 uchar_t bind; 607 608 /* 609 * If the non-underscore symbol exists and is undefined 610 * convert it to be a local. If the underscore has 611 * sa_symspec set (ie. it was created above) then simulate this 612 * as a weak alias. 613 */ 614 sdp->sd_ref = REF_REL_NEED; 615 sdp->sd_shndx = sdp->sd_sym->st_shndx = SHN_ABS; 616 sdp->sd_flags |= FLG_SY_SPECSEC; 617 sdp->sd_isc = NULL; 618 sdp->sd_sym->st_size = 0; 619 sdp->sd_sym->st_value = 0; 620 /* LINTED */ 621 sdp->sd_aux->sa_symspec = (Half)sdaux_id; 622 if (usdp->sd_aux->sa_symspec) { 623 usdp->sd_aux->sa_linkndx = 0; 624 sdp->sd_aux->sa_linkndx = 0; 625 bind = STB_WEAK; 626 } else 627 bind = STB_GLOBAL; 628 sdp->sd_sym->st_info = ELF_ST_INFO(bind, STT_OBJECT); 629 630 /* 631 * If a user hasn't specifically indicated the scope of 632 * this symbol be made local then leave it as global 633 * (ie. prevent automatic scoping). 634 */ 635 if (!(sdp->sd_flags1 & FLG_SY1_LOCL) && 636 (flags1 & FLG_SY1_GLOB)) { 637 sdp->sd_aux->sa_overndx = VER_NDX_GLOBAL; 638 if ((sdp->sd_flags1 & FLG_SY1_DIR) == 0) 639 sdp->sd_flags1 |= FLG_SY1_NDIR; 640 } 641 sdp->sd_flags1 |= flags1; 642 643 /* 644 * If the reference originated from a mapfile ensure 645 * we mark the symbol as used. 646 */ 647 if (sdp->sd_flags & FLG_SY_MAPREF) 648 sdp->sd_flags |= FLG_SY_MAPUSED; 649 650 DBG_CALL(Dbg_syms_updated(ofl, sdp, name)); 651 } 652 return (1); 653 } 654 655 656 /* 657 * Print undefined symbols. 658 */ 659 static Boolean undef_title = TRUE; 660 661 static void 662 sym_undef_title(Ofl_desc *ofl) 663 { 664 eprintf(ofl->ofl_lml, ERR_NONE, MSG_INTL(MSG_SYM_FMT_UNDEF), 665 MSG_INTL(MSG_SYM_UNDEF_ITM_11), 666 MSG_INTL(MSG_SYM_UNDEF_ITM_21), 667 MSG_INTL(MSG_SYM_UNDEF_ITM_12), 668 MSG_INTL(MSG_SYM_UNDEF_ITM_22)); 669 670 undef_title = FALSE; 671 } 672 673 /* 674 * Undefined symbols can fall into one of four types: 675 * 676 * o the symbol is really undefined (SHN_UNDEF). 677 * 678 * o versioning has been enabled, however this symbol has not been assigned 679 * to one of the defined versions. 680 * 681 * o the symbol has been defined by an implicitly supplied library, ie. one 682 * which was encounted because it was NEEDED by another library, rather 683 * than from a command line supplied library which would become the only 684 * dependency of the output file being produced. 685 * 686 * o the symbol has been defined by a version of a shared object that is 687 * not permitted for this link-edit. 688 * 689 * In all cases the file who made the first reference to this symbol will have 690 * been recorded via the `sa_rfile' pointer. 691 */ 692 typedef enum { 693 UNDEF, NOVERSION, IMPLICIT, NOTAVAIL, 694 BNDLOCAL 695 } Type; 696 697 static const Msg format[] = { 698 MSG_SYM_UND_UNDEF, /* MSG_INTL(MSG_SYM_UND_UNDEF) */ 699 MSG_SYM_UND_NOVER, /* MSG_INTL(MSG_SYM_UND_NOVER) */ 700 MSG_SYM_UND_IMPL, /* MSG_INTL(MSG_SYM_UND_IMPL) */ 701 MSG_SYM_UND_NOTA, /* MSG_INTL(MSG_SYM_UND_NOTA) */ 702 MSG_SYM_UND_BNDLOCAL /* MSG_INTL(MSG_SYM_UND_BNDLOCAL) */ 703 }; 704 705 static void 706 sym_undef_entry(Ofl_desc *ofl, Sym_desc *sdp, Type type) 707 { 708 const char *name1, *name2, *name3; 709 Ifl_desc *ifl = sdp->sd_file; 710 Sym_aux *sap = sdp->sd_aux; 711 712 if (undef_title) 713 sym_undef_title(ofl); 714 715 switch (type) { 716 case UNDEF: 717 case BNDLOCAL: 718 name1 = sap->sa_rfile; 719 break; 720 case NOVERSION: 721 name1 = ifl->ifl_name; 722 break; 723 case IMPLICIT: 724 name1 = sap->sa_rfile; 725 name2 = ifl->ifl_name; 726 break; 727 case NOTAVAIL: 728 name1 = sap->sa_rfile; 729 name2 = sap->sa_vfile; 730 name3 = ifl->ifl_verndx[sap->sa_dverndx].vi_name; 731 break; 732 default: 733 return; 734 } 735 736 eprintf(ofl->ofl_lml, ERR_NONE, MSG_INTL(format[type]), 737 demangle(sdp->sd_name), name1, name2, name3); 738 } 739 740 /* 741 * At this point all symbol input processing has been completed, therefore 742 * complete the symbol table entries by generating any necessary internal 743 * symbols. 744 */ 745 uintptr_t 746 ld_sym_spec(Ofl_desc *ofl) 747 { 748 if (!(ofl->ofl_flags & FLG_OF_RELOBJ)) { 749 750 DBG_CALL(Dbg_syms_spec_title(ofl->ofl_lml)); 751 752 if (sym_add_spec(MSG_ORIG(MSG_SYM_ETEXT), 753 MSG_ORIG(MSG_SYM_ETEXT_U), SDAUX_ID_ETEXT, 754 FLG_SY1_GLOB, ofl) == S_ERROR) 755 return (S_ERROR); 756 if (sym_add_spec(MSG_ORIG(MSG_SYM_EDATA), 757 MSG_ORIG(MSG_SYM_EDATA_U), SDAUX_ID_EDATA, 758 FLG_SY1_GLOB, ofl) == S_ERROR) 759 return (S_ERROR); 760 if (sym_add_spec(MSG_ORIG(MSG_SYM_END), 761 MSG_ORIG(MSG_SYM_END_U), SDAUX_ID_END, 762 FLG_SY1_GLOB, ofl) == S_ERROR) 763 return (S_ERROR); 764 if (sym_add_spec(MSG_ORIG(MSG_SYM_L_END), 765 MSG_ORIG(MSG_SYM_L_END_U), SDAUX_ID_END, 766 FLG_SY1_LOCL, ofl) == S_ERROR) 767 return (S_ERROR); 768 if (sym_add_spec(MSG_ORIG(MSG_SYM_L_START), 769 MSG_ORIG(MSG_SYM_L_START_U), SDAUX_ID_START, 770 FLG_SY1_LOCL, ofl) == S_ERROR) 771 return (S_ERROR); 772 773 /* 774 * Historically we've always produced a _DYNAMIC symbol, even 775 * for static executables (in which case its value will be 0). 776 */ 777 if (sym_add_spec(MSG_ORIG(MSG_SYM_DYNAMIC), 778 MSG_ORIG(MSG_SYM_DYNAMIC_U), SDAUX_ID_DYN, 779 FLG_SY1_GLOB, ofl) == S_ERROR) 780 return (S_ERROR); 781 782 if (OFL_ALLOW_DYNSYM(ofl)) 783 if (sym_add_spec(MSG_ORIG(MSG_SYM_PLKTBL), 784 MSG_ORIG(MSG_SYM_PLKTBL_U), SDAUX_ID_PLT, 785 FLG_SY1_GLOB, ofl) == S_ERROR) 786 return (S_ERROR); 787 788 if (ld_sym_find(MSG_ORIG(MSG_SYM_GOFTBL_U), SYM_NOHASH, 0, ofl)) 789 if (sym_add_spec(MSG_ORIG(MSG_SYM_GOFTBL), 790 MSG_ORIG(MSG_SYM_GOFTBL_U), SDAUX_ID_GOT, 791 FLG_SY1_GLOB, ofl) == S_ERROR) 792 return (S_ERROR); 793 } 794 return (1); 795 } 796 797 /* 798 * This routine checks to see if a symbols visibility needs to be reduced to 799 * either SYMBOLIC or LOCAL. This routine can be called from either 800 * reloc_init() or sym_validate(). 801 */ 802 void 803 ld_sym_adjust_vis(Sym_desc *sdp, Ofl_desc *ofl) 804 { 805 Word symvis, oflags = ofl->ofl_flags, oflags1 = ofl->ofl_flags1; 806 Sym *sym = sdp->sd_sym; 807 808 if ((sdp->sd_ref == REF_REL_NEED) && 809 (sdp->sd_sym->st_shndx != SHN_UNDEF)) { 810 /* 811 * If scoping is enabled, reduce any nonversioned global 812 * symbols (any symbol that has been processed for relocations 813 * will have already had this same reduction test applied). 814 * Indicate that the symbol has been reduced as it may be 815 * necessary to print these symbols later. 816 */ 817 if (((oflags & FLG_OF_AUTOLCL) || 818 (oflags1 & FLG_OF1_AUTOELM)) && 819 ((sdp->sd_flags1 & MSK_SY1_DEFINED) == 0)) { 820 821 sdp->sd_flags |= FLG_SY_REDUCED; 822 sdp->sd_flags1 |= FLG_SY1_LOCL; 823 824 if (ELF_ST_VISIBILITY(sym->st_other) != STV_INTERNAL) 825 sym->st_other = STV_HIDDEN | 826 (sym->st_other & ~MSK_SYM_VISIBILITY); 827 828 if (ofl->ofl_flags1 & 829 (FLG_OF1_REDLSYM | FLG_OF1_AUTOELM)) 830 sdp->sd_flags1 |= FLG_SY1_ELIM; 831 } 832 833 /* 834 * If '-Bsymbolic' is in effect - then bind all global symbols 835 * 'symbolically' and assign the STV_PROTECTED visibility 836 * attribute. 837 */ 838 if ((oflags & FLG_OF_SYMBOLIC) && 839 ((sdp->sd_flags1 & FLG_SY1_LOCL) == 0)) { 840 841 sdp->sd_flags1 |= FLG_SY1_PROT; 842 if (ELF_ST_VISIBILITY(sym->st_other) == STV_DEFAULT) 843 sym->st_other = STV_PROTECTED | 844 (sym->st_other & ~MSK_SYM_VISIBILITY); 845 } 846 } 847 848 /* 849 * Check to see if the symbol visibility needs to be adjusted due to any 850 * STV_* symbol attributes being set. 851 * 852 * STV_PROTECTED == symbolic binding 853 * STV_INTERNAL == reduce to local 854 * STV_HIDDEN == reduce to local 855 * 856 * Note, UNDEF symbols can be assigned a visibility, thus the refencing 857 * code can be dependent on this visibility. Here, by only ignoring 858 * REF_DYN_SEEN symbol definitions we can be assigning a visibility to 859 * REF_DYN_NEED. If the protected, or local assignment is made to 860 * a REF_DYN_NEED symbol, it will be caught later as an illegal 861 * visibility. 862 */ 863 if (!(oflags & FLG_OF_RELOBJ) && (sdp->sd_ref != REF_DYN_SEEN) && 864 (symvis = ELF_ST_VISIBILITY(sym->st_other))) { 865 if (symvis == STV_PROTECTED) 866 sdp->sd_flags1 |= FLG_SY1_PROT; 867 else if ((symvis == STV_INTERNAL) || (symvis == STV_HIDDEN)) 868 sdp->sd_flags1 |= FLG_SY1_LOCL; 869 } 870 871 /* 872 * Indicate that this symbol has had it's visibility checked so that 873 * we don't need to do this investigation again. 874 */ 875 sdp->sd_flags |= FLG_SY_VISIBLE; 876 } 877 878 /* 879 * Make sure a symbol definition is local to the object being built. 880 */ 881 static int 882 ensure_sym_local(Ofl_desc *ofl, Sym_desc *sdp, const char *str) 883 { 884 if (sdp->sd_sym->st_shndx == SHN_UNDEF) { 885 if (str) { 886 eprintf(ofl->ofl_lml, ERR_FATAL, 887 MSG_INTL(MSG_SYM_UNDEF), str, 888 demangle((char *)sdp->sd_name)); 889 } 890 return (1); 891 } 892 if (sdp->sd_ref != REF_REL_NEED) { 893 if (str) { 894 eprintf(ofl->ofl_lml, ERR_FATAL, 895 MSG_INTL(MSG_SYM_EXTERN), str, 896 demangle((char *)sdp->sd_name), 897 sdp->sd_file->ifl_name); 898 } 899 return (1); 900 } 901 902 sdp->sd_flags |= FLG_SY_UPREQD; 903 if (sdp->sd_isc) { 904 sdp->sd_isc->is_flags |= FLG_IS_SECTREF; 905 sdp->sd_isc->is_file->ifl_flags |= FLG_IF_FILEREF; 906 } 907 return (0); 908 } 909 910 /* 911 * Make sure all the symbol definitions required for initarray, finiarray, or 912 * preinitarray's are local to the object being built. 913 */ 914 static int 915 ensure_array_local(Ofl_desc *ofl, List *list, const char *str) 916 { 917 Listnode *lnp; 918 Sym_desc *sdp; 919 int ret = 0; 920 921 for (LIST_TRAVERSE(list, lnp, sdp)) 922 ret += ensure_sym_local(ofl, sdp, str); 923 924 return (ret); 925 } 926 927 /* 928 * After all symbol table input processing has been finished, and all relocation 929 * counting has been carried out (ie. no more symbols will be read, generated, 930 * or modified), validate and count the relevant entries: 931 * 932 * o check and print any undefined symbols remaining. Note that 933 * if a symbol has been defined by virtue of the inclusion of 934 * an implicit shared library, it is still classed as undefined. 935 * 936 * o count the number of global needed symbols together with the 937 * size of their associated name strings (if scoping has been 938 * indicated these symbols may be reduced to locals). 939 * 940 * o establish the size and alignment requirements for the global 941 * .bss section (the alignment of this section is based on the 942 * first symbol that it will contain). 943 */ 944 uintptr_t 945 ld_sym_validate(Ofl_desc *ofl) 946 { 947 Sym_avlnode *sav; 948 Sym_desc *sdp; 949 Sym *sym; 950 Word oflags = ofl->ofl_flags; 951 Word undef = 0, needed = 0, verdesc = 0; 952 Xword bssalign = 0, tlsalign = 0; 953 Xword bsssize = 0, tlssize = 0; 954 #if (defined(__i386) || defined(__amd64)) && defined(_ELF64) 955 Xword lbssalign = 0, lbsssize = 0; 956 #endif 957 int ret; 958 int allow_ldynsym; 959 960 /* 961 * If a symbol is undefined and this link-edit calls for no undefined 962 * symbols to remain (this is the default case when generating an 963 * executable but can be enforced for any object using -z defs), the 964 * symbol is classified as undefined and a fatal error condition will 965 * be indicated. 966 * 967 * If the symbol is undefined and we're creating a shared object with 968 * the -Bsymbolic flag, then the symbol is also classified as undefined 969 * and a warning condition will be indicated. 970 */ 971 if ((oflags & (FLG_OF_SHAROBJ | FLG_OF_SYMBOLIC)) == 972 (FLG_OF_SHAROBJ | FLG_OF_SYMBOLIC)) 973 undef = FLG_OF_WARN; 974 if (oflags & FLG_OF_NOUNDEF) 975 undef = FLG_OF_FATAL; 976 977 /* 978 * If the symbol is referenced from an implicitly included shared object 979 * (ie. it's not on the NEEDED list) then the symbol is also classified 980 * as undefined and a fatal error condition will be indicated. 981 */ 982 if ((oflags & FLG_OF_NOUNDEF) || !(oflags & FLG_OF_SHAROBJ)) 983 needed = FLG_OF_FATAL; 984 985 /* 986 * If the output image is being versioned all symbol definitions must be 987 * associated with a version. Any symbol that isn't is classified as 988 * undefined and a fatal error condition will be indicated. 989 */ 990 if ((oflags & FLG_OF_VERDEF) && (ofl->ofl_vercnt > VER_NDX_GLOBAL)) 991 verdesc = FLG_OF_FATAL; 992 993 allow_ldynsym = OFL_ALLOW_LDYNSYM(ofl); 994 /* 995 * Collect and validate the globals from the internal symbol table. 996 */ 997 for (sav = avl_first(&ofl->ofl_symavl); sav; 998 sav = AVL_NEXT(&ofl->ofl_symavl, sav)) { 999 Is_desc * isp; 1000 int undeferr = 0; 1001 1002 sdp = sav->sav_symdesc; 1003 1004 /* 1005 * If undefined symbols are allowed ignore any symbols that are 1006 * not needed. 1007 */ 1008 if (!(oflags & FLG_OF_NOUNDEF) && 1009 (sdp->sd_ref == REF_DYN_SEEN)) 1010 continue; 1011 1012 /* 1013 * If the symbol originates from an external or parent mapfile 1014 * reference and hasn't been matched to a reference from a 1015 * relocatable object, ignore it. 1016 */ 1017 if ((sdp->sd_flags & (FLG_SY_EXTERN | FLG_SY_PARENT)) && 1018 ((sdp->sd_flags & FLG_SY_MAPUSED) == 0)) { 1019 sdp->sd_flags |= FLG_SY_INVALID; 1020 continue; 1021 } 1022 1023 sym = sdp->sd_sym; 1024 1025 /* 1026 * Sanity check TLS. 1027 */ 1028 if ((ELF_ST_TYPE(sym->st_info) == STT_TLS) && 1029 (sym->st_size != 0) && (sym->st_shndx != SHN_UNDEF) && 1030 (sym->st_shndx != SHN_COMMON)) { 1031 Is_desc * isp = sdp->sd_isc; 1032 Ifl_desc * ifl = sdp->sd_file; 1033 1034 if ((isp == 0) || (isp->is_shdr == 0) || 1035 ((isp->is_shdr->sh_flags & SHF_TLS) == 0)) { 1036 eprintf(ofl->ofl_lml, ERR_FATAL, 1037 MSG_INTL(MSG_SYM_TLS), 1038 demangle(sdp->sd_name), ifl->ifl_name); 1039 ofl->ofl_flags |= FLG_OF_FATAL; 1040 continue; 1041 } 1042 } 1043 1044 if ((sdp->sd_flags & FLG_SY_VISIBLE) == 0) 1045 ld_sym_adjust_vis(sdp, ofl); 1046 1047 if ((sdp->sd_flags & FLG_SY_REDUCED) && 1048 (oflags & FLG_OF_PROCRED)) { 1049 DBG_CALL(Dbg_syms_reduce(ofl, DBG_SYM_REDUCE_GLOBAL, 1050 sdp, 0, 0)); 1051 } 1052 1053 /* 1054 * If building a shared object or executable, and this is a 1055 * non-weak UNDEF symbol with reduced visibility (STV_*), then 1056 * give a fatal error. 1057 */ 1058 if (!(oflags & FLG_OF_RELOBJ) && 1059 ELF_ST_VISIBILITY(sym->st_other) && 1060 (sym->st_shndx == SHN_UNDEF) && 1061 (ELF_ST_BIND(sym->st_info) != STB_WEAK)) { 1062 sym_undef_entry(ofl, sdp, BNDLOCAL); 1063 ofl->ofl_flags |= FLG_OF_FATAL; 1064 continue; 1065 } 1066 1067 /* 1068 * If this symbol is defined in a non-allocatable section, 1069 * reduce it to local symbol. 1070 */ 1071 if (((isp = sdp->sd_isc) != 0) && isp->is_shdr && 1072 ((isp->is_shdr->sh_flags & SHF_ALLOC) == 0)) { 1073 sdp->sd_flags |= FLG_SY_REDUCED; 1074 sdp->sd_flags1 |= FLG_SY1_LOCL; 1075 } 1076 1077 /* 1078 * If this symbol originated as a SHN_SUNW_IGNORE, it will have 1079 * been processed as an SHN_UNDEF. Return the symbol to its 1080 * original index for validation, and propagation to the output 1081 * file. 1082 */ 1083 if (sdp->sd_flags1 & FLG_SY1_IGNORE) 1084 sdp->sd_shndx = SHN_SUNW_IGNORE; 1085 1086 if (undef) { 1087 /* 1088 * If an non-weak reference remains undefined, or if a 1089 * mapfile reference is not bound to the relocatable 1090 * objects that make up the object being built, we have 1091 * a fatal error. 1092 * 1093 * The exceptions are symbols which are defined to be 1094 * found in the parent (FLG_SY_PARENT), which is really 1095 * only meaningful for direct binding, or are defined 1096 * external (FLG_SY_EXTERN) so as to suppress -zdefs 1097 * errors. 1098 * 1099 * Register symbols are always allowed to be UNDEF. 1100 * 1101 * Note that we don't include references created via -u 1102 * in the same shared object binding test. This is for 1103 * backward compatibility, in that a number of archive 1104 * makefile rules used -u to cause archive extraction. 1105 * These same rules have been cut and pasted to apply 1106 * to shared objects, and thus although the -u reference 1107 * is redundant, flagging it as fatal could cause some 1108 * build to fail. Also we have documented the use of 1109 * -u as a mechanism to cause binding to weak version 1110 * definitions, thus giving users an error condition 1111 * would be incorrect. 1112 */ 1113 if (!(sdp->sd_flags & FLG_SY_REGSYM) && 1114 ((sym->st_shndx == SHN_UNDEF) && 1115 ((ELF_ST_BIND(sym->st_info) != STB_WEAK) && 1116 ((sdp->sd_flags & 1117 (FLG_SY_PARENT | FLG_SY_EXTERN)) == 0)) || 1118 (((sdp->sd_flags & 1119 (FLG_SY_MAPREF | FLG_SY_MAPUSED)) == 1120 FLG_SY_MAPREF) && 1121 ((sdp->sd_flags1 & (FLG_SY1_LOCL | 1122 FLG_SY1_PROT)) == 0)))) { 1123 sym_undef_entry(ofl, sdp, UNDEF); 1124 ofl->ofl_flags |= undef; 1125 undeferr = 1; 1126 } 1127 1128 } else { 1129 /* 1130 * For building things like shared objects (or anything 1131 * -znodefs), undefined symbols are allowed. 1132 * 1133 * If a mapfile reference remains undefined the user 1134 * would probably like a warning at least (they've 1135 * usually mis-spelt the reference). Refer to the above 1136 * comments for discussion on -u references, which 1137 * are not tested for in the same manner. 1138 */ 1139 if ((sdp->sd_flags & 1140 (FLG_SY_MAPREF | FLG_SY_MAPUSED)) == 1141 FLG_SY_MAPREF) { 1142 sym_undef_entry(ofl, sdp, UNDEF); 1143 ofl->ofl_flags |= FLG_OF_WARN; 1144 undeferr = 1; 1145 } 1146 } 1147 1148 /* 1149 * If this symbol comes from a dependency mark the dependency 1150 * as required (-z ignore can result in unused dependencies 1151 * being dropped). If we need to record dependency versioning 1152 * information indicate what version of the needed shared object 1153 * this symbol is part of. Flag the symbol as undefined if it 1154 * has not been made available to us. 1155 */ 1156 if ((sdp->sd_ref == REF_DYN_NEED) && 1157 (!(sdp->sd_flags & FLG_SY_REFRSD))) { 1158 sdp->sd_file->ifl_flags |= FLG_IF_DEPREQD; 1159 1160 /* 1161 * Capture that we've bound to a symbol that doesn't 1162 * allow being directly bound to. 1163 */ 1164 if (sdp->sd_flags1 & FLG_SY1_NDIR) 1165 ofl->ofl_flags1 |= FLG_OF1_NDIRECT; 1166 1167 if (sdp->sd_file->ifl_vercnt) { 1168 int vndx; 1169 Ver_index * vip; 1170 1171 vndx = sdp->sd_aux->sa_dverndx; 1172 vip = &sdp->sd_file->ifl_verndx[vndx]; 1173 if (vip->vi_flags & FLG_VER_AVAIL) { 1174 vip->vi_flags |= FLG_VER_REFER; 1175 } else { 1176 sym_undef_entry(ofl, sdp, NOTAVAIL); 1177 ofl->ofl_flags |= FLG_OF_FATAL; 1178 continue; 1179 } 1180 } 1181 } 1182 1183 /* 1184 * Test that we do not bind to symbol supplied from an implicit 1185 * shared object. If a binding is from a weak reference it can 1186 * be ignored. 1187 */ 1188 if (needed && !undeferr && (sdp->sd_flags & FLG_SY_GLOBREF) && 1189 (sdp->sd_ref == REF_DYN_NEED) && 1190 (sdp->sd_flags & FLG_SY_NOTAVAIL)) { 1191 sym_undef_entry(ofl, sdp, IMPLICIT); 1192 ofl->ofl_flags |= needed; 1193 continue; 1194 } 1195 1196 /* 1197 * Test that a symbol isn't going to be reduced to local scope 1198 * which actually wants to bind to a shared object - if so it's 1199 * a fatal error. 1200 */ 1201 if ((sdp->sd_ref == REF_DYN_NEED) && 1202 (sdp->sd_flags1 & (FLG_SY1_LOCL | FLG_SY1_PROT))) { 1203 sym_undef_entry(ofl, sdp, BNDLOCAL); 1204 ofl->ofl_flags |= FLG_OF_FATAL; 1205 continue; 1206 } 1207 1208 /* 1209 * If the output image is to be versioned then all symbol 1210 * definitions must be associated with a version. 1211 */ 1212 if (verdesc && (sdp->sd_ref == REF_REL_NEED) && 1213 (sym->st_shndx != SHN_UNDEF) && 1214 (!(sdp->sd_flags1 & FLG_SY1_LOCL)) && 1215 (sdp->sd_aux->sa_overndx == 0)) { 1216 sym_undef_entry(ofl, sdp, NOVERSION); 1217 ofl->ofl_flags |= verdesc; 1218 continue; 1219 } 1220 1221 /* 1222 * If we don't need the symbol there's no need to process it 1223 * any further. 1224 */ 1225 if (sdp->sd_ref == REF_DYN_SEEN) 1226 continue; 1227 1228 /* 1229 * Calculate the size and alignment requirements for the global 1230 * .bss and .tls sections. If we're building a relocatable 1231 * object only account for scoped COMMON symbols (these will 1232 * be converted to .bss references). 1233 * 1234 * For partially initialized symbol, 1235 * if it is expanded, it goes to sunwdata1. 1236 * if it is local, it goes to .bss. 1237 * if the output is shared object, it goes to .sunwbss. 1238 * 1239 * Also refer to make_mvsections() in sunwmove.c 1240 */ 1241 if ((sym->st_shndx == SHN_COMMON) && 1242 (((oflags & FLG_OF_RELOBJ) == 0) || 1243 ((sdp->sd_flags1 & FLG_SY1_LOCL) && 1244 (oflags & FLG_OF_PROCRED)))) { 1245 int countbss = 0; 1246 1247 if (sdp->sd_psyminfo == 0) { 1248 countbss = 1; 1249 } else if ((sdp->sd_flags & FLG_SY_PAREXPN) != 0) { 1250 countbss = 0; 1251 } else if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) { 1252 countbss = 1; 1253 } else if ((ofl->ofl_flags & FLG_OF_SHAROBJ) != 0) { 1254 countbss = 0; 1255 } else 1256 countbss = 1; 1257 1258 if (countbss) { 1259 Xword * size, * align; 1260 1261 if (ELF_ST_TYPE(sym->st_info) != STT_TLS) { 1262 size = &bsssize; 1263 align = &bssalign; 1264 } else { 1265 size = &tlssize; 1266 align = &tlsalign; 1267 } 1268 *size = (Xword)S_ROUND(*size, sym->st_value) + 1269 sym->st_size; 1270 if (sym->st_value > *align) 1271 *align = sym->st_value; 1272 } 1273 } 1274 1275 #if (defined(__i386) || defined(__amd64)) && defined(_ELF64) 1276 /* 1277 * Calculate the size and alignment requirement for the global 1278 * .lbss. TLS or partially initialized symbols do not need to be 1279 * considered yet. 1280 */ 1281 if (sym->st_shndx == SHN_X86_64_LCOMMON) { 1282 lbsssize = (Xword)S_ROUND(lbsssize, sym->st_value) + 1283 sym->st_size; 1284 if (sym->st_value > lbssalign) 1285 lbssalign = sym->st_value; 1286 } 1287 #endif 1288 1289 /* 1290 * If a symbol was referenced via the command line 1291 * (ld -u <>, ...), then this counts as a reference against the 1292 * symbol. Mark any section that symbol is defined in. 1293 */ 1294 if (((isp = sdp->sd_isc) != 0) && 1295 (sdp->sd_flags & FLG_SY_CMDREF)) { 1296 isp->is_flags |= FLG_IS_SECTREF; 1297 isp->is_file->ifl_flags |= FLG_IF_FILEREF; 1298 } 1299 1300 /* 1301 * Update the symbol count and the associated name string size. 1302 * If scoping is in effect for this symbol assign it will be 1303 * assigned to the .symtab/.strtab sections. 1304 */ 1305 if ((sdp->sd_flags1 & FLG_SY1_LOCL) && 1306 (oflags & FLG_OF_PROCRED)) { 1307 /* 1308 * If symbol gets eliminated count it. 1309 * 1310 * If symbol gets reduced to local, 1311 * count it's size for the .symtab. 1312 */ 1313 if (sdp->sd_flags1 & FLG_SY1_ELIM) { 1314 ofl->ofl_elimcnt++; 1315 } else { 1316 ofl->ofl_scopecnt++; 1317 if ((((sdp->sd_flags & FLG_SY_REGSYM) == 0) || 1318 sym->st_name) && (st_insert(ofl->ofl_strtab, 1319 sdp->sd_name) == -1)) 1320 return (S_ERROR); 1321 if (allow_ldynsym && sym->st_name && 1322 (ELF_ST_TYPE(sym->st_info) == STT_FUNC)) { 1323 ofl->ofl_dynscopecnt++; 1324 if (st_insert(ofl->ofl_dynstrtab, 1325 sdp->sd_name) == -1) 1326 return (S_ERROR); 1327 } 1328 } 1329 } else { 1330 ofl->ofl_globcnt++; 1331 1332 /* 1333 * If global direct bindings are in effect, or this 1334 * symbol has bound to a dependency which was specified 1335 * as requiring direct bindings, and it hasn't 1336 * explicitly been defined as a non-direct binding 1337 * symbol, mark it. 1338 */ 1339 if (((ofl->ofl_dtflags_1 & DF_1_DIRECT) || (isp && 1340 (isp->is_file->ifl_flags & FLG_IF_DIRECT))) && 1341 ((sdp->sd_flags1 & FLG_SY1_NDIR) == 0)) 1342 sdp->sd_flags1 |= FLG_SY1_DIR; 1343 1344 /* 1345 * Insert the symbol name. 1346 */ 1347 if (((sdp->sd_flags & FLG_SY_REGSYM) == 0) || 1348 sym->st_name) { 1349 if (st_insert(ofl->ofl_strtab, 1350 sdp->sd_name) == -1) 1351 return (S_ERROR); 1352 1353 if (!(ofl->ofl_flags & FLG_OF_RELOBJ) && 1354 (st_insert(ofl->ofl_dynstrtab, 1355 sdp->sd_name) == -1)) 1356 return (S_ERROR); 1357 } 1358 1359 /* 1360 * If this section offers a global symbol - record that 1361 * fact. 1362 */ 1363 if (isp) { 1364 isp->is_flags |= FLG_IS_SECTREF; 1365 isp->is_file->ifl_flags |= FLG_IF_FILEREF; 1366 } 1367 } 1368 } 1369 1370 /* 1371 * If we've encountered a fatal error during symbol validation then 1372 * return now. 1373 */ 1374 if (ofl->ofl_flags & FLG_OF_FATAL) 1375 return (1); 1376 1377 /* 1378 * Now that symbol resolution is completed, scan any register symbols. 1379 * From now on, we're only interested in those that contribute to the 1380 * output file. 1381 */ 1382 if (ofl->ofl_regsyms) { 1383 int ndx; 1384 1385 for (ndx = 0; ndx < ofl->ofl_regsymsno; ndx++) { 1386 if ((sdp = ofl->ofl_regsyms[ndx]) == 0) 1387 continue; 1388 if (sdp->sd_ref != REF_REL_NEED) { 1389 ofl->ofl_regsyms[ndx] = 0; 1390 continue; 1391 } 1392 1393 ofl->ofl_regsymcnt++; 1394 if (sdp->sd_sym->st_name == 0) 1395 sdp->sd_name = MSG_ORIG(MSG_STR_EMPTY); 1396 1397 if ((sdp->sd_flags1 & FLG_SY1_LOCL) || 1398 (ELF_ST_BIND(sdp->sd_sym->st_info) == STB_LOCAL)) 1399 ofl->ofl_lregsymcnt++; 1400 } 1401 } 1402 1403 /* 1404 * Generate the .bss section now that we know its size and alignment. 1405 */ 1406 if (bsssize || !(oflags & FLG_OF_RELOBJ)) { 1407 if (ld_make_bss(ofl, bsssize, bssalign, MAKE_BSS) == S_ERROR) 1408 return (S_ERROR); 1409 } 1410 if (tlssize) { 1411 if (ld_make_bss(ofl, tlssize, tlsalign, MAKE_TLS) == S_ERROR) 1412 return (S_ERROR); 1413 } 1414 #if (defined(__i386) || defined(__amd64)) && defined(_ELF64) 1415 if (lbsssize && !(oflags & FLG_OF_RELOBJ)) { 1416 if (ld_make_bss(ofl, lbsssize, lbssalign, MAKE_LBSS) == S_ERROR) 1417 return (S_ERROR); 1418 } 1419 #endif 1420 1421 /* 1422 * Determine what entry point symbol we need, and if found save its 1423 * symbol descriptor so that we can update the ELF header entry with the 1424 * symbols value later (see update_oehdr). Make sure the symbol is 1425 * tagged to ensure its update in case -s is in effect. Use any -e 1426 * option first, or the default entry points `_start' and `main'. 1427 */ 1428 ret = 0; 1429 if (ofl->ofl_entry) { 1430 if (((sdp = ld_sym_find(ofl->ofl_entry, SYM_NOHASH, 0, 1431 ofl)) != NULL) && (ensure_sym_local(ofl, 1432 sdp, MSG_INTL(MSG_SYM_ENTRY)) == 0)) { 1433 ofl->ofl_entry = (void *)sdp; 1434 } else { 1435 ret++; 1436 } 1437 } else if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_START), 1438 SYM_NOHASH, 0, ofl)) != NULL) && (ensure_sym_local(ofl, 1439 sdp, 0) == 0)) { 1440 ofl->ofl_entry = (void *)sdp; 1441 1442 } else if (((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_MAIN), 1443 SYM_NOHASH, 0, ofl)) != NULL) && (ensure_sym_local(ofl, 1444 sdp, 0) == 0)) { 1445 ofl->ofl_entry = (void *)sdp; 1446 } 1447 1448 /* 1449 * If ld -zdtrace=<sym> was given, then validate that the symbol is 1450 * defined within the current object being built. 1451 */ 1452 if ((sdp = ofl->ofl_dtracesym) != 0) { 1453 ret += ensure_sym_local(ofl, sdp, MSG_ORIG(MSG_STR_DTRACE)); 1454 } 1455 1456 /* 1457 * If any initarray, finiarray or preinitarray functions have been 1458 * requested, make sure they are defined within the current object 1459 * being built. 1460 */ 1461 if (ofl->ofl_initarray.head) { 1462 ret += ensure_array_local(ofl, &ofl->ofl_initarray, 1463 MSG_ORIG(MSG_SYM_INITARRAY)); 1464 } 1465 if (ofl->ofl_finiarray.head) { 1466 ret += ensure_array_local(ofl, &ofl->ofl_finiarray, 1467 MSG_ORIG(MSG_SYM_FINIARRAY)); 1468 } 1469 if (ofl->ofl_preiarray.head) { 1470 ret += ensure_array_local(ofl, &ofl->ofl_preiarray, 1471 MSG_ORIG(MSG_SYM_PREINITARRAY)); 1472 } 1473 1474 if (ret) 1475 return (S_ERROR); 1476 1477 /* 1478 * If we're required to record any needed dependencies versioning 1479 * information calculate it now that all symbols have been validated. 1480 */ 1481 if ((oflags & (FLG_OF_VERNEED | FLG_OF_NOVERSEC)) == FLG_OF_VERNEED) 1482 return (ld_vers_check_need(ofl)); 1483 else 1484 return (1); 1485 } 1486 1487 /* 1488 * qsort(3c) comparison function. As an optimization for associating weak 1489 * symbols to their strong counterparts sort global symbols according to their 1490 * address and binding. 1491 */ 1492 static int 1493 compare(const void * sdpp1, const void * sdpp2) 1494 { 1495 Sym_desc * sdp1 = *((Sym_desc **)sdpp1); 1496 Sym_desc * sdp2 = *((Sym_desc **)sdpp2); 1497 Sym * sym1, * sym2; 1498 uchar_t bind1, bind2; 1499 1500 /* 1501 * Symbol descriptors may be zero, move these to the front of the 1502 * sorted array. 1503 */ 1504 if (sdp1 == 0) 1505 return (-1); 1506 if (sdp2 == 0) 1507 return (1); 1508 1509 sym1 = sdp1->sd_sym; 1510 sym2 = sdp2->sd_sym; 1511 1512 /* 1513 * Compare the symbols value (address). 1514 */ 1515 if (sym1->st_value > sym2->st_value) 1516 return (1); 1517 if (sym1->st_value < sym2->st_value) 1518 return (-1); 1519 1520 bind1 = ELF_ST_BIND(sym1->st_info); 1521 bind2 = ELF_ST_BIND(sym2->st_info); 1522 1523 /* 1524 * If two symbols have the same address place the weak symbol before 1525 * any strong counterpart. 1526 */ 1527 if (bind1 > bind2) 1528 return (-1); 1529 if (bind1 < bind2) 1530 return (1); 1531 1532 return (0); 1533 } 1534 1535 1536 /* 1537 * Process the symbol table for the specified input file. At this point all 1538 * input sections from this input file have been assigned an input section 1539 * descriptor which is saved in the `ifl_isdesc' array. 1540 * 1541 * o local symbols are saved (as is) if the input file is a 1542 * relocatable object 1543 * 1544 * o global symbols are added to the linkers internal symbol 1545 * table if they are not already present, otherwise a symbol 1546 * resolution function is called upon to resolve the conflict. 1547 */ 1548 uintptr_t 1549 ld_sym_process(Is_desc *isc, Ifl_desc *ifl, Ofl_desc *ofl) 1550 { 1551 Sym *sym = (Sym *)isc->is_indata->d_buf; 1552 Word *symshndx = 0; 1553 Shdr *shdr = isc->is_shdr; 1554 Sym_desc *sdp; 1555 size_t strsize; 1556 char *strs; 1557 uchar_t type, bind; 1558 Word ndx, hash, local, total; 1559 Half etype = ifl->ifl_ehdr->e_type; 1560 const char *symsecname, *strsecname; 1561 avl_index_t where; 1562 1563 /* 1564 * Its possible that a file may contain more that one symbol table, 1565 * ie. .dynsym and .symtab in a shared library. Only process the first 1566 * table (here, we assume .dynsym comes before .symtab). 1567 */ 1568 if (ifl->ifl_symscnt) 1569 return (1); 1570 1571 if (isc->is_symshndx) 1572 symshndx = isc->is_symshndx->is_indata->d_buf; 1573 1574 DBG_CALL(Dbg_syms_process(ofl->ofl_lml, ifl)); 1575 1576 if (isc->is_name) 1577 symsecname = isc->is_name; 1578 else 1579 symsecname = MSG_ORIG(MSG_STR_EMPTY); 1580 1581 /* 1582 * From the symbol tables section header information determine which 1583 * strtab table is needed to locate the actual symbol names. 1584 */ 1585 if (ifl->ifl_flags & FLG_IF_HSTRTAB) { 1586 ndx = shdr->sh_link; 1587 if ((ndx == 0) || (ndx >= ifl->ifl_shnum)) { 1588 eprintf(ofl->ofl_lml, ERR_FATAL, 1589 MSG_INTL(MSG_FIL_INVSHLINK), 1590 ifl->ifl_name, symsecname, EC_XWORD(ndx)); 1591 return (S_ERROR); 1592 } 1593 strsize = ifl->ifl_isdesc[ndx]->is_shdr->sh_size; 1594 strs = ifl->ifl_isdesc[ndx]->is_indata->d_buf; 1595 if (ifl->ifl_isdesc[ndx]->is_name) 1596 strsecname = ifl->ifl_isdesc[ndx]->is_name; 1597 else 1598 strsecname = MSG_ORIG(MSG_STR_EMPTY); 1599 } else { 1600 /* 1601 * There is no string table section in this input file 1602 * although there are symbols in this symbol table section. 1603 * This means that these symbols do not have names. 1604 * Currently, only scratch register symbols are allowed 1605 * not to have names. 1606 */ 1607 strsize = 0; 1608 strs = (char *)MSG_ORIG(MSG_STR_EMPTY); 1609 strsecname = MSG_ORIG(MSG_STR_EMPTY); 1610 } 1611 1612 /* 1613 * Determine the number of local symbols together with the total 1614 * number we have to process. 1615 */ 1616 total = (Word)(shdr->sh_size / shdr->sh_entsize); 1617 local = shdr->sh_info; 1618 1619 /* 1620 * Allocate a symbol table index array and a local symbol array 1621 * (global symbols are processed and added to the ofl->ofl_symbkt[] 1622 * array). If we are dealing with a relocatable object, allocate the 1623 * local symbol descriptors. If this isn't a relocatable object we 1624 * still have to process any shared object locals to determine if any 1625 * register symbols exist. Although these aren't added to the output 1626 * image, they are used as part of symbol resolution. 1627 */ 1628 if ((ifl->ifl_oldndx = libld_malloc((size_t)(total * 1629 sizeof (Sym_desc *)))) == 0) 1630 return (S_ERROR); 1631 if ((etype == ET_REL) && local) { 1632 if ((ifl->ifl_locs = 1633 libld_calloc(sizeof (Sym_desc), local)) == 0) 1634 return (S_ERROR); 1635 /* LINTED */ 1636 ifl->ifl_locscnt = (Word)local; 1637 } 1638 ifl->ifl_symscnt = total; 1639 1640 /* 1641 * If there are local symbols to save add them to the symbol table 1642 * index array. 1643 */ 1644 if (local) { 1645 int allow_ldynsym = OFL_ALLOW_LDYNSYM(ofl); 1646 for (sym++, ndx = 1; ndx < local; sym++, ndx++) { 1647 Word shndx, sdflags = FLG_SY_CLEAN; 1648 const char *name; 1649 Sym_desc *rsdp; 1650 1651 /* 1652 * Determine the associated section index. 1653 */ 1654 if (symshndx && (sym->st_shndx == SHN_XINDEX)) 1655 shndx = symshndx[ndx]; 1656 else if ((shndx = sym->st_shndx) >= SHN_LORESERVE) 1657 sdflags |= FLG_SY_SPECSEC; 1658 1659 /* 1660 * Check if st_name has a valid value or not. 1661 */ 1662 if ((name = string(ofl, ifl, sym, strs, strsize, ndx, 1663 shndx, symsecname, strsecname, &sdflags)) == 0) { 1664 ofl->ofl_flags |= FLG_OF_FATAL; 1665 continue; 1666 } 1667 1668 /* 1669 * If this local symbol table originates from a shared 1670 * object, then we're only interested in recording 1671 * register symbols. As local symbol descriptors aren't 1672 * allocated for shared objects, one will be allocated 1673 * to associated with the register symbol. This symbol 1674 * won't become part of the output image, but we must 1675 * process it to test for register conflicts. 1676 */ 1677 rsdp = sdp = 0; 1678 if (sdflags & FLG_SY_REGSYM) { 1679 if ((rsdp = ld_reg_find(sym, ofl)) != 0) { 1680 /* 1681 * The fact that another register def- 1682 * inition has been found is fatal. 1683 * Call the verification routine to get 1684 * the error message and move on. 1685 */ 1686 (void) ld_reg_check(rsdp, sym, name, 1687 ifl, ofl); 1688 continue; 1689 } 1690 1691 if (etype == ET_DYN) { 1692 if ((sdp = libld_calloc( 1693 sizeof (Sym_desc), 1)) == 0) 1694 return (S_ERROR); 1695 sdp->sd_ref = REF_DYN_SEEN; 1696 } 1697 } else if (etype == ET_DYN) 1698 continue; 1699 1700 /* 1701 * Fill in the remaining symbol descriptor information. 1702 */ 1703 if (sdp == 0) { 1704 sdp = &(ifl->ifl_locs[ndx]); 1705 sdp->sd_ref = REF_REL_NEED; 1706 } 1707 if (rsdp == 0) { 1708 sdp->sd_name = name; 1709 sdp->sd_sym = sym; 1710 sdp->sd_shndx = shndx; 1711 sdp->sd_flags = sdflags; 1712 sdp->sd_file = ifl; 1713 ifl->ifl_oldndx[ndx] = sdp; 1714 } 1715 1716 DBG_CALL(Dbg_syms_entry(ofl->ofl_lml, ndx, sdp)); 1717 1718 /* 1719 * Reclassify any SHN_SUNW_IGNORE symbols to SHN_UNDEF 1720 * so as to simplify future processing. 1721 */ 1722 if (sym->st_shndx == SHN_SUNW_IGNORE) { 1723 sdp->sd_shndx = shndx = SHN_UNDEF; 1724 sdp->sd_flags1 |= 1725 (FLG_SY1_IGNORE | FLG_SY1_ELIM); 1726 } 1727 1728 /* 1729 * Process any register symbols. 1730 */ 1731 if (sdp->sd_flags & FLG_SY_REGSYM) { 1732 /* 1733 * Add a diagnostic to indicate we've caught a 1734 * register symbol, as this can be useful if a 1735 * register conflict is later discovered. 1736 */ 1737 DBG_CALL(Dbg_syms_entered(ofl, sym, sdp)); 1738 1739 /* 1740 * If this register symbol hasn't already been 1741 * recorded, enter it now. 1742 */ 1743 if ((rsdp == 0) && 1744 (ld_reg_enter(sdp, ofl) == 0)) 1745 return (S_ERROR); 1746 } 1747 1748 /* 1749 * Assign an input section. 1750 */ 1751 if ((sym->st_shndx != SHN_UNDEF) && 1752 ((sdp->sd_flags & FLG_SY_SPECSEC) == 0)) 1753 sdp->sd_isc = ifl->ifl_isdesc[shndx]; 1754 1755 /* 1756 * If this symbol falls within the range of a section 1757 * being discarded, then discard the symbol itself. 1758 * There is no reason to keep this local symbol. 1759 */ 1760 if (sdp->sd_isc && 1761 (sdp->sd_isc->is_flags & FLG_IS_DISCARD)) { 1762 sdp->sd_flags |= FLG_SY_ISDISC; 1763 DBG_CALL(Dbg_syms_discarded(ofl->ofl_lml, 1764 sdp, sdp->sd_isc)); 1765 continue; 1766 } 1767 1768 /* 1769 * Skip any section symbols as new versions of these 1770 * will be created. 1771 */ 1772 if ((type = ELF_ST_TYPE(sym->st_info)) == STT_SECTION) { 1773 if (sym->st_shndx == SHN_UNDEF) { 1774 eprintf(ofl->ofl_lml, ERR_WARNING, 1775 MSG_INTL(MSG_SYM_INVSHNDX), 1776 demangle(sdp->sd_name), 1777 ifl->ifl_name, 1778 conv_sym_shndx(sym->st_shndx)); 1779 } 1780 continue; 1781 } 1782 1783 /* 1784 * Sanity check for TLS 1785 */ 1786 if ((sym->st_size != 0) && ((type == STT_TLS) && 1787 (sym->st_shndx != SHN_COMMON))) { 1788 Is_desc *isp = sdp->sd_isc; 1789 1790 if ((isp == 0) || (isp->is_shdr == 0) || 1791 ((isp->is_shdr->sh_flags & SHF_TLS) == 0)) { 1792 eprintf(ofl->ofl_lml, ERR_FATAL, 1793 MSG_INTL(MSG_SYM_TLS), 1794 demangle(sdp->sd_name), 1795 ifl->ifl_name); 1796 ofl->ofl_flags |= FLG_OF_FATAL; 1797 continue; 1798 } 1799 } 1800 1801 /* 1802 * Carry our some basic sanity checks (these are just 1803 * some of the erroneous symbol entries we've come 1804 * across, there's probably a lot more). The symbol 1805 * will not be carried forward to the output file, which 1806 * won't be a problem unless a relocation is required 1807 * against it. 1808 */ 1809 if (((sdp->sd_flags & FLG_SY_SPECSEC) && 1810 ((sym->st_shndx == SHN_COMMON)) || 1811 ((type == STT_FILE) && 1812 (sym->st_shndx != SHN_ABS))) || 1813 (sdp->sd_isc && (sdp->sd_isc->is_osdesc == 0))) { 1814 eprintf(ofl->ofl_lml, ERR_WARNING, 1815 MSG_INTL(MSG_SYM_INVSHNDX), 1816 demangle(sdp->sd_name), ifl->ifl_name, 1817 conv_sym_shndx(sym->st_shndx)); 1818 sdp->sd_isc = NULL; 1819 sdp->sd_flags |= FLG_SY_INVALID; 1820 continue; 1821 } 1822 1823 /* 1824 * As these local symbols will become part of the output 1825 * image, record their number and name string size. 1826 * Globals are counted after all input file processing 1827 * (and hence symbol resolution) is complete during 1828 * sym_validate(). 1829 */ 1830 if (!(ofl->ofl_flags1 & FLG_OF1_REDLSYM)) { 1831 ofl->ofl_locscnt++; 1832 1833 if ((((sdp->sd_flags & FLG_SY_REGSYM) == 0) || 1834 sym->st_name) && (st_insert(ofl->ofl_strtab, 1835 sdp->sd_name) == -1)) 1836 return (S_ERROR); 1837 1838 if (allow_ldynsym && sym->st_name && 1839 ((type == STT_FUNC) || 1840 (type == STT_FILE))) { 1841 ofl->ofl_dynlocscnt++; 1842 if (st_insert(ofl->ofl_dynstrtab, 1843 sdp->sd_name) == -1) 1844 return (S_ERROR); 1845 } 1846 } 1847 } 1848 } 1849 1850 /* 1851 * Now scan the global symbols entering them in the internal symbol 1852 * table or resolving them as necessary. 1853 */ 1854 sym = (Sym *)isc->is_indata->d_buf; 1855 sym += local; 1856 /* LINTED */ 1857 for (ndx = (int)local; ndx < total; sym++, ndx++) { 1858 const char *name; 1859 Word shndx, sdflags = 0; 1860 1861 /* 1862 * Determine the associated section index. 1863 */ 1864 if (symshndx && (sym->st_shndx == SHN_XINDEX)) { 1865 shndx = symshndx[ndx]; 1866 } else { 1867 shndx = sym->st_shndx; 1868 if (sym->st_shndx >= SHN_LORESERVE) 1869 sdflags |= FLG_SY_SPECSEC; 1870 } 1871 1872 /* 1873 * Check if st_name has a valid value or not. 1874 */ 1875 if ((name = string(ofl, ifl, sym, strs, strsize, ndx, shndx, 1876 symsecname, strsecname, &sdflags)) == 0) { 1877 ofl->ofl_flags |= FLG_OF_FATAL; 1878 continue; 1879 } 1880 1881 /* 1882 * The linker itself will generate symbols for _end, _etext, 1883 * _edata, _DYNAMIC and _PROCEDURE_LINKAGE_TABLE_, so don't 1884 * bother entering these symbols from shared objects. This 1885 * results in some wasted resolution processing, which is hard 1886 * to feel, but if nothing else, pollutes diagnostic relocation 1887 * output. 1888 */ 1889 if (name[0] && (etype == ET_DYN) && (sym->st_size == 0) && 1890 (ELF_ST_TYPE(sym->st_info) == STT_OBJECT) && 1891 (name[0] == '_') && ((name[1] == 'e') || 1892 (name[1] == 'D') || (name[1] == 'P')) && 1893 ((strcmp(name, MSG_ORIG(MSG_SYM_ETEXT_U)) == 0) || 1894 (strcmp(name, MSG_ORIG(MSG_SYM_EDATA_U)) == 0) || 1895 (strcmp(name, MSG_ORIG(MSG_SYM_END_U)) == 0) || 1896 (strcmp(name, MSG_ORIG(MSG_SYM_DYNAMIC_U)) == 0) || 1897 (strcmp(name, MSG_ORIG(MSG_SYM_PLKTBL_U)) == 0))) { 1898 ifl->ifl_oldndx[ndx] = 0; 1899 continue; 1900 } 1901 1902 /* 1903 * Determine and validate the symbols binding. 1904 */ 1905 bind = ELF_ST_BIND(sym->st_info); 1906 if ((bind != STB_GLOBAL) && (bind != STB_WEAK)) { 1907 eprintf(ofl->ofl_lml, ERR_WARNING, 1908 MSG_INTL(MSG_SYM_NONGLOB), demangle(name), 1909 ifl->ifl_name, conv_sym_info_bind(bind, 0)); 1910 continue; 1911 } 1912 1913 /* 1914 * If this symbol falls within the range of a section being 1915 * discarded, then discard the symbol itself. 1916 */ 1917 if (((sdflags & FLG_SY_SPECSEC) == 0) && 1918 (sym->st_shndx != SHN_UNDEF)) { 1919 Is_desc *isp; 1920 1921 if (shndx >= ifl->ifl_shnum) { 1922 /* 1923 * Carry our some basic sanity checks 1924 * The symbol will not be carried forward to 1925 * the output file, which won't be a problem 1926 * unless a relocation is required against it. 1927 */ 1928 eprintf(ofl->ofl_lml, ERR_WARNING, 1929 MSG_INTL(MSG_SYM_INVSHNDX), demangle(name), 1930 ifl->ifl_name, 1931 conv_sym_shndx(sym->st_shndx)); 1932 continue; 1933 } 1934 1935 isp = ifl->ifl_isdesc[shndx]; 1936 if (isp && (isp->is_flags & FLG_IS_DISCARD)) { 1937 if ((sdp = 1938 libld_calloc(sizeof (Sym_desc), 1)) == 0) 1939 return (S_ERROR); 1940 1941 /* 1942 * Create a dummy symbol entry so that if we 1943 * find any references to this discarded symbol 1944 * we can compensate. 1945 */ 1946 sdp->sd_name = name; 1947 sdp->sd_sym = sym; 1948 sdp->sd_file = ifl; 1949 sdp->sd_isc = isp; 1950 sdp->sd_flags = FLG_SY_ISDISC; 1951 ifl->ifl_oldndx[ndx] = sdp; 1952 1953 DBG_CALL(Dbg_syms_discarded(ofl->ofl_lml, sdp, 1954 sdp->sd_isc)); 1955 continue; 1956 } 1957 } 1958 1959 /* 1960 * If the symbol does not already exist in the internal symbol 1961 * table add it, otherwise resolve the conflict. If the symbol 1962 * from this file is kept, retain its symbol table index for 1963 * possible use in associating a global alias. 1964 */ 1965 /* LINTED */ 1966 hash = (Word)elf_hash((const char *)name); 1967 if ((sdp = ld_sym_find(name, hash, &where, ofl)) == NULL) { 1968 DBG_CALL(Dbg_syms_global(ofl->ofl_lml, ndx, name)); 1969 if ((sdp = ld_sym_enter(name, sym, hash, ifl, ofl, ndx, 1970 shndx, sdflags, 0, &where)) == (Sym_desc *)S_ERROR) 1971 return (S_ERROR); 1972 1973 } else if (ld_sym_resolve(sdp, sym, ifl, ofl, ndx, shndx, 1974 sdflags) == S_ERROR) 1975 return (S_ERROR); 1976 1977 /* 1978 * After we've compared a defined symbol in one shared 1979 * object, flag the symbol so we don't compare it again. 1980 */ 1981 if ((etype == ET_DYN) && (sym->st_shndx != SHN_UNDEF) && 1982 ((sdp->sd_flags & FLG_SY_SOFOUND) == 0)) 1983 sdp->sd_flags |= FLG_SY_SOFOUND; 1984 1985 /* 1986 * If the symbol is accepted from this file retain the symbol 1987 * index for possible use in aliasing. 1988 */ 1989 if (sdp->sd_file == ifl) 1990 sdp->sd_symndx = ndx; 1991 1992 ifl->ifl_oldndx[ndx] = sdp; 1993 1994 /* 1995 * If we've accepted a register symbol, continue to validate 1996 * it. 1997 */ 1998 if (sdp->sd_flags & FLG_SY_REGSYM) { 1999 Sym_desc *rsdp; 2000 2001 if ((rsdp = ld_reg_find(sdp->sd_sym, ofl)) == 0) { 2002 if (ld_reg_enter(sdp, ofl) == 0) 2003 return (S_ERROR); 2004 } else if (rsdp != sdp) { 2005 (void) ld_reg_check(rsdp, sdp->sd_sym, 2006 sdp->sd_name, ifl, ofl); 2007 } 2008 } 2009 } 2010 2011 /* 2012 * If this is a shared object scan the globals one more time and 2013 * associate any weak/global associations. This association is needed 2014 * should the weak definition satisfy a reference in the dynamic 2015 * executable: 2016 * 2017 * o if the symbol is a data item it will be copied to the 2018 * executables address space, thus we must also reassociate the 2019 * alias symbol with its new location in the executable. 2020 * 2021 * o if the symbol is a function then we may need to promote the 2022 * symbols binding from undefined weak to undefined, otherwise the 2023 * run-time linker will not generate the correct relocation error 2024 * should the symbol not be found. 2025 * 2026 * The true association between a weak/strong symbol pair is that both 2027 * symbol entries are identical, thus first we created a sorted symbol 2028 * list keyed off of the symbols value (if the value is the same chances 2029 * are the rest of the symbols data is). This list is then scanned for 2030 * weak symbols, and if one is found then any strong association will 2031 * exist in the following entries. Thus we just have to scan one 2032 * (typical single alias) or more (in the uncommon instance of multiple 2033 * weak to strong associations) entries to determine if a match exists. 2034 */ 2035 if (ifl->ifl_ehdr->e_type == ET_DYN) { 2036 Sym_desc ** sort; 2037 size_t size = (total - local) * sizeof (Sym_desc *); 2038 2039 if ((sort = libld_malloc(size)) == 0) 2040 return (S_ERROR); 2041 (void) memcpy((void *)sort, &ifl->ifl_oldndx[local], size); 2042 2043 qsort(sort, (total - local), sizeof (Sym_desc *), compare); 2044 2045 for (ndx = 0; ndx < (total - local); ndx++) { 2046 Sym_desc * wsdp = sort[ndx]; 2047 Sym * wsym; 2048 int sndx; 2049 2050 if (wsdp == 0) 2051 continue; 2052 2053 wsym = wsdp->sd_sym; 2054 2055 if ((ELF_ST_BIND(wsym->st_info) != STB_WEAK) || 2056 (wsdp->sd_sym->st_shndx == SHN_UNDEF) || 2057 (wsdp->sd_flags & FLG_SY_SPECSEC)) 2058 continue; 2059 2060 /* 2061 * We have a weak symbol, if it has a strong alias it 2062 * will have been sorted to one of the following sort 2063 * table entries. Note that we could have multiple weak 2064 * symbols aliased to one strong (if this occurs then 2065 * the strong symbol only maintains one alias back to 2066 * the last weak). 2067 */ 2068 for (sndx = ndx + 1; sndx < (total - local); sndx++) { 2069 Sym_desc * ssdp = sort[sndx]; 2070 Sym * ssym; 2071 2072 if (ssdp == 0) 2073 break; 2074 2075 ssym = ssdp->sd_sym; 2076 2077 if (wsym->st_value != ssym->st_value) 2078 break; 2079 2080 if ((ssdp->sd_file == ifl) && 2081 (wsdp->sd_file == ifl) && 2082 (wsym->st_size == ssym->st_size) && 2083 (ssdp->sd_sym->st_shndx != SHN_UNDEF) && 2084 (ELF_ST_BIND(ssym->st_info) != STB_WEAK) && 2085 ((ssdp->sd_flags & FLG_SY_SPECSEC) == 0)) { 2086 ssdp->sd_aux->sa_linkndx = 2087 (Word)wsdp->sd_symndx; 2088 wsdp->sd_aux->sa_linkndx = 2089 (Word)ssdp->sd_symndx; 2090 break; 2091 } 2092 } 2093 } 2094 } 2095 return (1); 2096 } 2097 2098 /* 2099 * Add an undefined symbol to the symbol table (ie. from -u name option) 2100 */ 2101 Sym_desc * 2102 ld_sym_add_u(const char *name, Ofl_desc *ofl) 2103 { 2104 Sym *sym; 2105 Ifl_desc *ifl = 0, *_ifl; 2106 Sym_desc *sdp; 2107 Word hash; 2108 Listnode *lnp; 2109 avl_index_t where; 2110 const char *cmdline = MSG_INTL(MSG_STR_COMMAND); 2111 2112 /* 2113 * If the symbol reference already exists indicate that a reference 2114 * also came from the command line. 2115 */ 2116 /* LINTED */ 2117 hash = (Word)elf_hash(name); 2118 if (sdp = ld_sym_find(name, hash, &where, ofl)) { 2119 if (sdp->sd_ref == REF_DYN_SEEN) 2120 sdp->sd_ref = REF_DYN_NEED; 2121 return (sdp); 2122 } 2123 2124 /* 2125 * Determine whether a pseudo input file descriptor exists to represent 2126 * the command line, as any global symbol needs an input file descriptor 2127 * during any symbol resolution (refer to map_ifl() which provides a 2128 * similar method for adding symbols from mapfiles). 2129 */ 2130 for (LIST_TRAVERSE(&ofl->ofl_objs, lnp, _ifl)) 2131 if (strcmp(_ifl->ifl_name, cmdline) == 0) { 2132 ifl = _ifl; 2133 break; 2134 } 2135 2136 /* 2137 * If no descriptor exists create one. 2138 */ 2139 if (ifl == 0) { 2140 if ((ifl = libld_calloc(sizeof (Ifl_desc), 1)) == 2141 (Ifl_desc *)0) 2142 return ((Sym_desc *)S_ERROR); 2143 ifl->ifl_name = cmdline; 2144 ifl->ifl_flags = FLG_IF_NEEDED | FLG_IF_FILEREF; 2145 if ((ifl->ifl_ehdr = libld_calloc(sizeof (Ehdr), 2146 1)) == 0) 2147 return ((Sym_desc *)S_ERROR); 2148 ifl->ifl_ehdr->e_type = ET_REL; 2149 2150 if (list_appendc(&ofl->ofl_objs, ifl) == 0) 2151 return ((Sym_desc *)S_ERROR); 2152 } 2153 2154 /* 2155 * Allocate a symbol structure and add it to the global symbol table. 2156 */ 2157 if ((sym = libld_calloc(sizeof (Sym), 1)) == 0) 2158 return ((Sym_desc *)S_ERROR); 2159 sym->st_info = ELF_ST_INFO(STB_GLOBAL, STT_NOTYPE); 2160 sym->st_shndx = SHN_UNDEF; 2161 2162 DBG_CALL(Dbg_syms_process(ofl->ofl_lml, ifl)); 2163 DBG_CALL(Dbg_syms_global(ofl->ofl_lml, 0, name)); 2164 sdp = ld_sym_enter(name, sym, hash, ifl, ofl, 0, SHN_UNDEF, 2165 0, 0, &where); 2166 sdp->sd_flags &= ~FLG_SY_CLEAN; 2167 sdp->sd_flags |= FLG_SY_CMDREF; 2168 2169 return (sdp); 2170 } 2171