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 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 27 * Use is subject to license terms. 28 */ 29 30 /* 31 * set-up for relocations 32 */ 33 34 #define ELF_TARGET_AMD64 35 #define ELF_TARGET_SPARC 36 37 #include <string.h> 38 #include <stdio.h> 39 #include <alloca.h> 40 #include <debug.h> 41 #include "msg.h" 42 #include "_libld.h" 43 44 /* 45 * Set up the relocation table flag test macros so that they use the 46 * relocation table for the current target machine. 47 */ 48 #define IS_PLT(X) RELTAB_IS_PLT(X, ld_targ.t_mr.mr_reloc_table) 49 #define IS_GOT_RELATIVE(X) \ 50 RELTAB_IS_GOT_RELATIVE(X, ld_targ.t_mr.mr_reloc_table) 51 #define IS_GOT_PC(X) RELTAB_IS_GOT_PC(X, ld_targ.t_mr.mr_reloc_table) 52 #define IS_GOTPCREL(X) RELTAB_IS_GOTPCREL(X, ld_targ.t_mr.mr_reloc_table) 53 #define IS_GOT_BASED(X) RELTAB_IS_GOT_BASED(X, ld_targ.t_mr.mr_reloc_table) 54 #define IS_GOT_OPINS(X) RELTAB_IS_GOT_OPINS(X, ld_targ.t_mr.mr_reloc_table) 55 #define IS_GOT_REQUIRED(X) \ 56 RELTAB_IS_GOT_REQUIRED(X, ld_targ.t_mr.mr_reloc_table) 57 #define IS_PC_RELATIVE(X) RELTAB_IS_PC_RELATIVE(X, ld_targ.t_mr.mr_reloc_table) 58 #define IS_ADD_RELATIVE(X) \ 59 RELTAB_IS_ADD_RELATIVE(X, ld_targ.t_mr.mr_reloc_table) 60 #define IS_REGISTER(X) RELTAB_IS_REGISTER(X, ld_targ.t_mr.mr_reloc_table) 61 #define IS_NOTSUP(X) RELTAB_IS_NOTSUP(X, ld_targ.t_mr.mr_reloc_table) 62 #define IS_SEG_RELATIVE(X) \ 63 RELTAB_IS_SEG_RELATIVE(X, ld_targ.t_mr.mr_reloc_table) 64 #define IS_EXTOFFSET(X) RELTAB_IS_EXTOFFSET(X, ld_targ.t_mr.mr_reloc_table) 65 #define IS_SEC_RELATIVE(X) \ 66 RELTAB_IS_SEC_RELATIVE(X, ld_targ.t_mr.mr_reloc_table) 67 #define IS_TLS_INS(X) RELTAB_IS_TLS_INS(X, ld_targ.t_mr.mr_reloc_table) 68 #define IS_TLS_GD(X) RELTAB_IS_TLS_GD(X, ld_targ.t_mr.mr_reloc_table) 69 #define IS_TLS_LD(X) RELTAB_IS_TLS_LD(X, ld_targ.t_mr.mr_reloc_table) 70 #define IS_TLS_IE(X) RELTAB_IS_TLS_IE(X, ld_targ.t_mr.mr_reloc_table) 71 #define IS_TLS_LE(X) RELTAB_IS_TLS_LE(X, ld_targ.t_mr.mr_reloc_table) 72 #define IS_LOCALBND(X) RELTAB_IS_LOCALBND(X, ld_targ.t_mr.mr_reloc_table) 73 #define IS_SIZE(X) RELTAB_IS_SIZE(X, ld_targ.t_mr.mr_reloc_table) 74 75 /* 76 * Structure to hold copy relocation items. 77 */ 78 typedef struct copy_rel { 79 Sym_desc *c_sdp; /* symbol descriptor to be copied */ 80 Addr c_val; /* original symbol value */ 81 } Copy_rel; 82 83 /* 84 * For each copy relocation symbol, determine if the symbol is: 85 * 1) to be *disp* relocated at runtime 86 * 2) a reference symbol for *disp* relocation 87 * 3) possibly *disp* relocated at ld time. 88 * 89 * The first and the second are serious errors. 90 */ 91 static void 92 is_disp_copied(Ofl_desc *ofl, Copy_rel *crp) 93 { 94 Ifl_desc *ifl = crp->c_sdp->sd_file; 95 Sym_desc *sdp = crp->c_sdp; 96 Addr symaddr = crp->c_val; 97 Is_desc *irel; 98 Aliste idx; 99 Conv_inv_buf_t inv_buf; 100 101 /* 102 * This symbol may not be *disp* relocated at run time, but could 103 * already have been *disp* relocated when the shared object was 104 * created. Warn the user. 105 */ 106 if ((ifl->ifl_flags & FLG_IF_DISPDONE) && 107 (ofl->ofl_flags & FLG_OF_VERBOSE)) 108 eprintf(ofl->ofl_lml, ERR_WARNING, MSG_INTL(MSG_REL_DISPREL2), 109 conv_reloc_type(ifl->ifl_ehdr->e_machine, 110 ld_targ.t_m.m_r_copy, 0, &inv_buf), 111 ifl->ifl_name, demangle(sdp->sd_name)); 112 113 if ((ifl->ifl_flags & FLG_IF_DISPPEND) == 0) 114 return; 115 116 /* 117 * Traverse the input relocation sections. 118 */ 119 for (APLIST_TRAVERSE(ifl->ifl_relsect, idx, irel)) { 120 Sym_desc *rsdp; 121 Is_desc *trel; 122 Rel *rend, *reloc; 123 Xword rsize, entsize; 124 125 trel = ifl->ifl_isdesc[irel->is_shdr->sh_info]; 126 rsize = irel->is_shdr->sh_size; 127 entsize = irel->is_shdr->sh_entsize; 128 reloc = (Rel *)irel->is_indata->d_buf; 129 130 /* 131 * Decide entry size 132 */ 133 if ((entsize == 0) || (entsize > rsize)) { 134 if (irel->is_shdr->sh_type == SHT_RELA) 135 entsize = sizeof (Rela); 136 else 137 entsize = sizeof (Rel); 138 } 139 140 /* 141 * Traverse the relocation entries. 142 */ 143 for (rend = (Rel *)((uintptr_t)reloc + (uintptr_t)rsize); 144 reloc < rend; 145 reloc = (Rel *)((uintptr_t)reloc + (uintptr_t)entsize)) { 146 const char *str; 147 Word rstndx; 148 149 if (IS_PC_RELATIVE(ELF_R_TYPE(reloc->r_info, 150 ld_targ.t_m.m_mach)) == 0) 151 continue; 152 153 /* 154 * Determine if symbol is referenced from a relocation. 155 */ 156 rstndx = (Word) ELF_R_SYM(reloc->r_info); 157 rsdp = ifl->ifl_oldndx[rstndx]; 158 if (rsdp == sdp) { 159 if ((str = demangle(rsdp->sd_name)) != 160 rsdp->sd_name) { 161 char *_str = alloca(strlen(str) + 1); 162 (void) strcpy(_str, str); 163 str = (const char *)_str; 164 } 165 eprintf(ofl->ofl_lml, 166 ERR_WARNING, MSG_INTL(MSG_REL_DISPREL1), 167 conv_reloc_type(ifl->ifl_ehdr->e_machine, 168 (uint_t)ELF_R_TYPE(reloc->r_info, 169 ld_targ.t_m.m_mach), 170 0, &inv_buf), ifl->ifl_name, str, 171 MSG_INTL(MSG_STR_UNKNOWN), 172 EC_XWORD(reloc->r_offset), 173 demangle(sdp->sd_name)); 174 } 175 176 /* 177 * Determine whether the relocation entry is relocating 178 * this symbol. 179 */ 180 if ((sdp->sd_isc != trel) || 181 (reloc->r_offset < symaddr) || 182 (reloc->r_offset >= 183 (symaddr + sdp->sd_sym->st_size))) 184 continue; 185 186 /* 187 * This symbol is truely *disp* relocated, so should 188 * really be fixed by user. 189 */ 190 if ((str = demangle(sdp->sd_name)) != sdp->sd_name) { 191 char *_str = alloca(strlen(str) + 1); 192 (void) strcpy(_str, str); 193 str = (const char *)_str; 194 } 195 eprintf(ofl->ofl_lml, ERR_WARNING, 196 MSG_INTL(MSG_REL_DISPREL1), 197 conv_reloc_type(ifl->ifl_ehdr->e_machine, 198 (uint_t)ELF_R_TYPE(reloc->r_info, 199 ld_targ.t_m.m_mach), 0, &inv_buf), 200 ifl->ifl_name, demangle(rsdp->sd_name), str, 201 EC_XWORD(reloc->r_offset), str); 202 } 203 } 204 } 205 206 /* 207 * The number of symbols provided by some objects can be very large. Use a 208 * binary search to match the associated value to a symbol table entry. 209 */ 210 static int 211 disp_bsearch(const void *key, const void *array) 212 { 213 Addr kvalue, avalue; 214 Ssv_desc *ssvp = (Ssv_desc *)array; 215 216 kvalue = *((Addr *)key); 217 avalue = ssvp->ssv_value; 218 219 if (avalue > kvalue) 220 return (-1); 221 if ((avalue < kvalue) && 222 ((avalue + ssvp->ssv_sdp->sd_sym->st_size) <= kvalue)) 223 return (1); 224 return (0); 225 } 226 227 /* 228 * Given a sorted list of symbols, look for a symbol in which the relocation 229 * offset falls between the [sym.st_value - sym.st_value + sym.st_size]. Since 230 * the symbol list is maintained in sorted order, we can bail once the 231 * relocation offset becomes less than the symbol values. The symbol is 232 * returned for use in error diagnostics. 233 */ 234 static Sym_desc * 235 disp_scansyms(Ifl_desc * ifl, Rel_desc *rld, Boolean rlocal, int inspect, 236 Ofl_desc *ofl) 237 { 238 Sym_desc *tsdp, *rsdp; 239 Sym *rsym, *tsym; 240 Ssv_desc *ssvp; 241 uchar_t rtype, ttype; 242 Addr value; 243 244 /* 245 * Sorted symbol values have been uniquified by adding their associated 246 * section offset. Uniquify the relocation offset by adding its 247 * associated section offset, and search for the symbol. 248 */ 249 value = rld->rel_roffset; 250 if (rld->rel_isdesc->is_shdr) 251 value += rld->rel_isdesc->is_shdr->sh_offset; 252 253 if ((ssvp = bsearch((void *)&value, (void *)ifl->ifl_sortsyms, 254 ifl->ifl_sortcnt, sizeof (Ssv_desc), &disp_bsearch)) != 0) 255 tsdp = ssvp->ssv_sdp; 256 else 257 tsdp = 0; 258 259 if (inspect) 260 return (tsdp); 261 262 /* 263 * Determine the relocation reference symbol and its type. 264 */ 265 rsdp = rld->rel_sym; 266 rsym = rsdp->sd_sym; 267 rtype = ELF_ST_TYPE(rsym->st_info); 268 269 /* 270 * If there is no target symbol to match the relocation offset, then the 271 * offset is effectively local data. If the relocation symbol is global 272 * data we have a potential for this displacement relocation to be 273 * invalidated should the global symbol be copied. 274 */ 275 if (tsdp == 0) { 276 if ((rlocal == TRUE) || 277 ((rtype != STT_OBJECT) && (rtype != STT_SECTION))) 278 return (tsdp); 279 } else { 280 /* 281 * If both symbols are local, no copy relocations can occur to 282 * either symbol. Note, this test is very similar to the test 283 * used in ld_sym_adjust_vis(). 284 */ 285 if ((rlocal == TRUE) && ((tsdp->sd_flags & FLG_SY_HIDDEN) || 286 (ELF_ST_BIND(tsdp->sd_sym->st_info) != STB_GLOBAL) || 287 ((ofl->ofl_flags & (FLG_OF_AUTOLCL | FLG_OF_AUTOELM)) && 288 ((tsdp->sd_flags & MSK_SY_NOAUTO) == 0)))) 289 return (tsdp); 290 291 /* 292 * Determine the relocation target symbols type. 293 */ 294 tsym = tsdp->sd_sym; 295 ttype = ELF_ST_TYPE(tsym->st_info); 296 297 /* 298 * If the reference symbol is local, and the target isn't a 299 * data element, then no copy relocations can occur to either 300 * symbol. Note, this catches pc-relative relocations against 301 * the _GLOBAL_OFFSET_TABLE_, which is effectively treated as 302 * a local symbol. 303 */ 304 if ((rlocal == TRUE) && (ttype != STT_OBJECT) && 305 (ttype != STT_SECTION)) 306 return (tsdp); 307 308 /* 309 * Finally, one of the symbols must reference a data element. 310 */ 311 if ((rtype != STT_OBJECT) && (rtype != STT_SECTION) && 312 (ttype != STT_OBJECT) && (ttype != STT_SECTION)) 313 return (tsdp); 314 } 315 316 /* 317 * We have two global symbols, at least one of which is a data item. 318 * The last case where a displacement relocation can be ignored, is 319 * if the reference symbol is included in the target symbol. 320 */ 321 value = rsym->st_value; 322 if ((rld->rel_flags & FLG_REL_RELA) == FLG_REL_RELA) 323 value += rld->rel_raddend; 324 325 if ((rld->rel_roffset >= value) && 326 (rld->rel_roffset < (value + rsym->st_size))) 327 return (tsdp); 328 329 /* 330 * We have a displacement relocation that could be compromised by a 331 * copy relocation of one of the associated data items. 332 */ 333 rld->rel_flags |= FLG_REL_DISP; 334 return (tsdp); 335 } 336 337 void 338 ld_disp_errmsg(const char *msg, Rel_desc *rsp, Ofl_desc *ofl) 339 { 340 Sym_desc *sdp; 341 const char *str; 342 Ifl_desc *ifl = rsp->rel_isdesc->is_file; 343 Conv_inv_buf_t inv_buf; 344 345 if ((sdp = disp_scansyms(ifl, rsp, 0, 1, ofl)) != 0) 346 str = demangle(sdp->sd_name); 347 else 348 str = MSG_INTL(MSG_STR_UNKNOWN); 349 350 eprintf(ofl->ofl_lml, ERR_WARNING, msg, 351 conv_reloc_type(ifl->ifl_ehdr->e_machine, rsp->rel_rtype, 352 0, &inv_buf), ifl->ifl_name, rsp->rel_sname, str, 353 EC_OFF(rsp->rel_roffset)); 354 } 355 356 /* 357 * qsort(3C) comparison routine used for the disp_sortsyms(). 358 */ 359 static int 360 disp_qsort(const void * s1, const void * s2) 361 { 362 Ssv_desc *ssvp1 = ((Ssv_desc *)s1); 363 Ssv_desc *ssvp2 = ((Ssv_desc *)s2); 364 Addr val1 = ssvp1->ssv_value; 365 Addr val2 = ssvp2->ssv_value; 366 367 if (val1 > val2) 368 return (1); 369 if (val1 < val2) 370 return (-1); 371 return (0); 372 } 373 374 /* 375 * Determine whether a displacement relocation is between a local and global 376 * symbol pair. One symbol is used to perform the relocation, and the other 377 * is the destination offset of the relocation. 378 */ 379 static uintptr_t 380 disp_inspect(Ofl_desc *ofl, Rel_desc *rld, Boolean rlocal) 381 { 382 Is_desc *isp = rld->rel_isdesc; 383 Ifl_desc *ifl = rld->rel_isdesc->is_file; 384 385 /* 386 * If the input files symbols haven't been sorted yet, do so. 387 */ 388 if (ifl->ifl_sortsyms == 0) { 389 Word ondx, nndx; 390 391 if ((ifl->ifl_sortsyms = libld_malloc((ifl->ifl_symscnt + 1) * 392 sizeof (Ssv_desc))) == 0) 393 return (S_ERROR); 394 395 for (ondx = 0, nndx = 0; ondx < ifl->ifl_symscnt; ondx++) { 396 Sym_desc *sdp; 397 Addr value; 398 399 /* 400 * As symbol resolution has already occurred, various 401 * symbols from this object may have been satisfied 402 * from other objects. Only select symbols from this 403 * object. For the displacement test, we only really 404 * need to observe data definitions, however, later as 405 * part of providing warning disgnostics, relating the 406 * relocation offset to a symbol is desirable. Thus, 407 * collect all symbols that define a memory area. 408 */ 409 if (((sdp = ifl->ifl_oldndx[ondx]) == 0) || 410 (sdp->sd_sym->st_shndx == SHN_UNDEF) || 411 (sdp->sd_sym->st_shndx >= SHN_LORESERVE) || 412 (sdp->sd_ref != REF_REL_NEED) || 413 (sdp->sd_file != ifl) || 414 (sdp->sd_sym->st_size == 0)) 415 continue; 416 417 /* 418 * As a further optimization for later checking, mark 419 * this section if this a global data definition. 420 */ 421 if (sdp->sd_isc && (ondx >= ifl->ifl_locscnt)) 422 sdp->sd_isc->is_flags |= FLG_IS_GDATADEF; 423 424 /* 425 * Capture the symbol. Within relocatable objects, a 426 * symbols value is its offset within its associated 427 * section. Add the section offset to this value to 428 * uniquify the symbol. 429 */ 430 value = sdp->sd_sym->st_value; 431 if (sdp->sd_isc && sdp->sd_isc->is_shdr) 432 value += sdp->sd_isc->is_shdr->sh_offset; 433 434 ifl->ifl_sortsyms[nndx].ssv_value = value; 435 ifl->ifl_sortsyms[nndx].ssv_sdp = sdp; 436 nndx++; 437 } 438 439 /* 440 * Sort the list based on the symbols value (address). 441 */ 442 if ((ifl->ifl_sortcnt = nndx) != 0) 443 qsort(ifl->ifl_sortsyms, nndx, sizeof (Ssv_desc), 444 &disp_qsort); 445 } 446 447 /* 448 * If the reference symbol is local, and the section being relocated 449 * contains no global definitions, neither can be the target of a copy 450 * relocation. 451 */ 452 if ((rlocal == FALSE) && ((isp->is_flags & FLG_IS_GDATADEF) == 0)) 453 return (1); 454 455 /* 456 * Otherwise determine whether this relocation symbol and its offset 457 * could be candidates for a copy relocation. 458 */ 459 if (ifl->ifl_sortcnt) 460 (void) disp_scansyms(ifl, rld, rlocal, 0, ofl); 461 return (1); 462 } 463 464 /* 465 * Output relocation numbers can vary considerably between building executables 466 * or shared objects (pic vs. non-pic), etc. But, they typically aren't very 467 * large, so for these objects use a standard bucket size. For building 468 * relocatable objects, typically there will be an output relocation for every 469 * input relocation. 470 */ 471 Rel_cache * 472 ld_add_rel_cache(Ofl_desc *ofl, APlist **alpp, size_t *nextsize, size_t low, 473 size_t hi) 474 { 475 Rel_cache *rcp; 476 size_t size; 477 APlist *alp = *alpp; 478 479 /* 480 * If there is space available in the present cache bucket, return the 481 * next free entry. 482 */ 483 if (alp && ((rcp = alp->apl_data[aplist_nitems(alp) - 1]) != NULL) && 484 (rcp->rc_free < rcp->rc_end)) 485 return (rcp); 486 487 /* 488 * Allocate a new bucket. 489 */ 490 if (*nextsize == 0) { 491 if ((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) { 492 if ((size = ofl->ofl_relocincnt) == 0) 493 size = low; 494 if (size > hi) 495 *nextsize = hi; 496 else 497 *nextsize = low; 498 } else 499 *nextsize = size = hi; 500 } else 501 size = *nextsize; 502 503 size = size * sizeof (Rel_desc); 504 505 if (((rcp = libld_malloc(sizeof (Rel_cache) + size)) == NULL) || 506 (aplist_append(alpp, rcp, AL_CNT_OFL_RELS) == NULL)) 507 return ((Rel_cache *)S_ERROR); 508 509 /* LINTED */ 510 rcp->rc_free = (Rel_desc *)(rcp + 1); 511 /* LINTED */ 512 rcp->rc_end = (Rel_desc *)((char *)rcp->rc_free + size); 513 514 return (rcp); 515 } 516 517 /* 518 * Add an active relocation record. 519 */ 520 uintptr_t 521 ld_add_actrel(Word flags, Rel_desc *rsp, Ofl_desc *ofl) 522 { 523 Rel_desc *arsp; 524 Rel_cache *rcp; 525 static size_t nextsize = 0; 526 527 /* 528 * If no relocation cache structures are available, allocate a new 529 * one and link it into the bucket list. 530 */ 531 if ((rcp = ld_add_rel_cache(ofl, &ofl->ofl_actrels, &nextsize, 532 REL_LAIDESCNO, REL_HAIDESCNO)) == (Rel_cache *)S_ERROR) 533 return (S_ERROR); 534 535 arsp = rcp->rc_free; 536 537 *arsp = *rsp; 538 arsp->rel_flags |= flags; 539 540 rcp->rc_free++; 541 ofl->ofl_actrelscnt++; 542 543 /* 544 * Any GOT relocation reference requires the creation of a .got table. 545 * Most references to a .got require a .got entry, which is accounted 546 * for with the ofl_gotcnt counter. However, some references are 547 * relative to the .got table, but require no .got entry. This test 548 * insures a .got is created regardless of the type of reference. 549 */ 550 if (IS_GOT_REQUIRED(arsp->rel_rtype)) 551 ofl->ofl_flags |= FLG_OF_BLDGOT; 552 553 /* 554 * If this is a displacement relocation generate a warning. 555 */ 556 if (arsp->rel_flags & FLG_REL_DISP) { 557 ofl->ofl_dtflags_1 |= DF_1_DISPRELDNE; 558 559 if (ofl->ofl_flags & FLG_OF_VERBOSE) 560 ld_disp_errmsg(MSG_INTL(MSG_REL_DISPREL3), arsp, ofl); 561 } 562 563 DBG_CALL(Dbg_reloc_ars_entry(ofl->ofl_lml, ELF_DBG_LD, 564 arsp->rel_isdesc->is_shdr->sh_type, ld_targ.t_m.m_mach, arsp)); 565 return (1); 566 } 567 568 /* 569 * In the platform specific machrel.XXX.c files, we sometimes write 570 * a value directly into the got/plt. These function can be used when 571 * the running linker has the opposite byte order of the object being 572 * produced. 573 */ 574 Word 575 ld_bswap_Word(Word v) 576 { 577 return (BSWAP_WORD(v)); 578 } 579 580 581 Xword 582 ld_bswap_Xword(Xword v) 583 { 584 return (BSWAP_XWORD(v)); 585 } 586 587 588 uintptr_t 589 ld_reloc_GOT_relative(Boolean local, Rel_desc *rsp, Ofl_desc *ofl) 590 { 591 Sym_desc *sdp = rsp->rel_sym; 592 ofl_flag_t flags = ofl->ofl_flags; 593 Gotndx *gnp; 594 595 /* 596 * If this is the first time we've seen this symbol in a GOT 597 * relocation we need to assign it a GOT token. Once we've got 598 * all of the GOT's assigned we can assign the actual indexes. 599 */ 600 if ((gnp = (*ld_targ.t_mr.mr_find_got_ndx)(sdp->sd_GOTndxs, 601 GOT_REF_GENERIC, ofl, rsp)) == 0) { 602 Word rtype = rsp->rel_rtype; 603 604 if ((*ld_targ.t_mr.mr_assign_got_ndx)(&(sdp->sd_GOTndxs), NULL, 605 GOT_REF_GENERIC, ofl, rsp, sdp) == S_ERROR) 606 return (S_ERROR); 607 608 /* 609 * Now we initialize the GOT table entry. 610 * 611 * Pseudo code to describe the the decisions below: 612 * 613 * If (local) 614 * then 615 * enter symbol value in GOT table entry 616 * if (Shared Object) 617 * then 618 * create Relative relocation against symbol 619 * fi 620 * else 621 * clear GOT table entry 622 * create a GLOB_DAT relocation against symbol 623 * fi 624 */ 625 if (local == TRUE) { 626 if (flags & FLG_OF_SHAROBJ) { 627 if (ld_add_actrel((FLG_REL_GOT | FLG_REL_GOTCL), 628 rsp, ofl) == S_ERROR) 629 return (S_ERROR); 630 631 /* 632 * Add a RELATIVE relocation if this is 633 * anything but a ABS symbol. 634 */ 635 if ((((sdp->sd_flags & FLG_SY_SPECSEC) == 0) || 636 (sdp->sd_sym->st_shndx != SHN_ABS)) || 637 (sdp->sd_aux && sdp->sd_aux->sa_symspec)) { 638 rsp->rel_rtype = 639 ld_targ.t_m.m_r_relative; 640 if ((*ld_targ.t_mr.mr_add_outrel) 641 ((FLG_REL_GOT | FLG_REL_ADVAL), rsp, 642 ofl) == S_ERROR) 643 return (S_ERROR); 644 rsp->rel_rtype = rtype; 645 } 646 } else { 647 if (ld_add_actrel(FLG_REL_GOT, rsp, 648 ofl) == S_ERROR) 649 return (S_ERROR); 650 } 651 } else { 652 rsp->rel_rtype = ld_targ.t_m.m_r_glob_dat; 653 if ((*ld_targ.t_mr.mr_add_outrel)(FLG_REL_GOT, 654 rsp, ofl) == S_ERROR) 655 return (S_ERROR); 656 rsp->rel_rtype = rtype; 657 } 658 } else { 659 if ((*ld_targ.t_mr.mr_assign_got_ndx)(&(sdp->sd_GOTndxs), gnp, 660 GOT_REF_GENERIC, ofl, rsp, sdp) == S_ERROR) 661 return (S_ERROR); 662 } 663 664 /* 665 * Perform relocation to GOT table entry. 666 */ 667 return (ld_add_actrel(NULL, rsp, ofl)); 668 } 669 670 /* 671 * Perform relocations for PLT's 672 */ 673 uintptr_t 674 ld_reloc_plt(Rel_desc *rsp, Ofl_desc *ofl) 675 { 676 Sym_desc *sdp = rsp->rel_sym; 677 678 switch (ld_targ.t_m.m_mach) { 679 case EM_AMD64: 680 /* 681 * AMD64 TLS code sequences do not use a unique TLS 682 * relocation to reference the __tls_get_addr() function call. 683 */ 684 if ((ofl->ofl_flags & FLG_OF_EXEC) && 685 (strcmp(sdp->sd_name, MSG_ORIG(MSG_SYM_TLSGETADDR_U)) == 686 0)) 687 return (ld_add_actrel(FLG_REL_TLSFIX, rsp, ofl)); 688 break; 689 690 case EM_386: 691 /* 692 * GNUC IA32 TLS code sequences do not use a unique TLS 693 * relocation to reference the ___tls_get_addr() function call. 694 */ 695 if ((ofl->ofl_flags & FLG_OF_EXEC) && 696 (strcmp(sdp->sd_name, MSG_ORIG(MSG_SYM_TLSGETADDR_UU)) == 697 0)) 698 return (ld_add_actrel(FLG_REL_TLSFIX, rsp, ofl)); 699 break; 700 } 701 702 /* 703 * if (not PLT yet assigned) 704 * then 705 * assign PLT index to symbol 706 * build output JMP_SLOT relocation 707 * fi 708 */ 709 if (sdp->sd_aux->sa_PLTndx == 0) { 710 Word ortype = rsp->rel_rtype; 711 712 (*ld_targ.t_mr.mr_assign_plt_ndx)(sdp, ofl); 713 714 /* 715 * If this symbol is binding to a LAZYLOADED object then 716 * set the LAZYLD symbol flag. 717 */ 718 if (sdp->sd_file && 719 (sdp->sd_file->ifl_flags & FLG_IF_LAZYLD)) 720 sdp->sd_flags |= FLG_SY_LAZYLD; 721 722 rsp->rel_rtype = ld_targ.t_m.m_r_jmp_slot; 723 if ((*ld_targ.t_mr.mr_add_outrel)(FLG_REL_PLT, rsp, ofl) == 724 S_ERROR) 725 return (S_ERROR); 726 rsp->rel_rtype = ortype; 727 } 728 729 /* 730 * Perform relocation to PLT table entry. 731 */ 732 if ((ofl->ofl_flags & FLG_OF_SHAROBJ) && 733 IS_ADD_RELATIVE(rsp->rel_rtype)) { 734 Word ortype = rsp->rel_rtype; 735 736 rsp->rel_rtype = ld_targ.t_m.m_r_relative; 737 if ((*ld_targ.t_mr.mr_add_outrel)(FLG_REL_ADVAL, rsp, ofl) == 738 S_ERROR) 739 return (S_ERROR); 740 rsp->rel_rtype = ortype; 741 return (1); 742 } else 743 return (ld_add_actrel(NULL, rsp, ofl)); 744 } 745 746 /* 747 * process GLOBAL undefined and ref_dyn_need symbols. 748 */ 749 static uintptr_t 750 reloc_exec(Rel_desc *rsp, Ofl_desc *ofl) 751 { 752 Sym_desc *_sdp, *sdp = rsp->rel_sym; 753 Sym_aux *sap = sdp->sd_aux; 754 Sym *sym = sdp->sd_sym; 755 Addr stval; 756 757 /* 758 * Reference is to a function so simply create a plt entry for it. 759 */ 760 if (ELF_ST_TYPE(sym->st_info) == STT_FUNC) 761 return (ld_reloc_plt(rsp, ofl)); 762 763 /* 764 * Catch absolutes - these may cause a text relocation. 765 */ 766 if ((sdp->sd_flags & FLG_SY_SPECSEC) && (sym->st_shndx == SHN_ABS)) { 767 if ((ofl->ofl_flags1 & FLG_OF1_ABSEXEC) == 0) 768 return ((*ld_targ.t_mr.mr_add_outrel)(NULL, rsp, ofl)); 769 770 /* 771 * If -zabsexec is set then promote the ABSOLUTE symbol to 772 * current the current object and perform the relocation now. 773 */ 774 sdp->sd_ref = REF_REL_NEED; 775 return (ld_add_actrel(NULL, rsp, ofl)); 776 } 777 778 /* 779 * If the relocation is against a writable section simply compute the 780 * necessary output relocation. As an optimization, if the symbol has 781 * already been transformed into a copy relocation then we can perform 782 * the relocation directly (copy relocations should only be generated 783 * for references from the text segment and these relocations are 784 * normally carried out before we get to the data segment relocations). 785 */ 786 if ((ELF_ST_TYPE(sym->st_info) == STT_OBJECT) && 787 (rsp->rel_osdesc->os_shdr->sh_flags & SHF_WRITE)) { 788 if (sdp->sd_flags & FLG_SY_MVTOCOMM) 789 return (ld_add_actrel(NULL, rsp, ofl)); 790 else 791 return ((*ld_targ.t_mr.mr_add_outrel)(NULL, rsp, ofl)); 792 } 793 794 /* 795 * If the reference isn't to an object (normally because a .type 796 * directive hasn't defined in some assembler source), then simply apply 797 * a generic relocation (this has a tendency to result in text 798 * relocations). 799 */ 800 if (ELF_ST_TYPE(sym->st_info) != STT_OBJECT) { 801 Conv_inv_buf_t inv_buf; 802 803 eprintf(ofl->ofl_lml, ERR_WARNING, MSG_INTL(MSG_REL_UNEXPSYM), 804 conv_sym_info_type(sdp->sd_file->ifl_ehdr->e_machine, 805 ELF_ST_TYPE(sym->st_info), 0, &inv_buf), 806 rsp->rel_isdesc->is_file->ifl_name, 807 demangle(rsp->rel_sname), sdp->sd_file->ifl_name); 808 return ((*ld_targ.t_mr.mr_add_outrel)(NULL, rsp, ofl)); 809 } 810 811 /* 812 * Prepare for generating a copy relocation. 813 * 814 * If this symbol is one of an alias pair, we need to insure both 815 * symbols become part of the output (the strong symbol will be used to 816 * maintain the symbols state). And, if we did raise the precedence of 817 * a symbol we need to check and see if this is a weak symbol. If it is 818 * we want to use it's strong counter part. 819 * 820 * The results of this logic should be: 821 * rel_usym: assigned to strong 822 * rel_sym: assigned to symbol to perform 823 * copy_reloc against (weak or strong). 824 */ 825 if (sap->sa_linkndx) { 826 _sdp = sdp->sd_file->ifl_oldndx[sap->sa_linkndx]; 827 828 if (_sdp->sd_ref < sdp->sd_ref) { 829 _sdp->sd_ref = sdp->sd_ref; 830 _sdp->sd_flags |= FLG_SY_REFRSD; 831 832 /* 833 * As we're going to replicate a symbol from a shared 834 * object, retain its correct binding status. 835 */ 836 if (ELF_ST_BIND(_sdp->sd_sym->st_info) == STB_GLOBAL) 837 _sdp->sd_flags |= FLG_SY_GLOBREF; 838 839 } else if (_sdp->sd_ref > sdp->sd_ref) { 840 sdp->sd_ref = _sdp->sd_ref; 841 sdp->sd_flags |= FLG_SY_REFRSD; 842 843 /* 844 * As we're going to replicate a symbol from a shared 845 * object, retain its correct binding status. 846 */ 847 if (ELF_ST_BIND(sym->st_info) == STB_GLOBAL) 848 sdp->sd_flags |= FLG_SY_GLOBREF; 849 } 850 851 /* 852 * If this is a weak symbol then we want to move the strong 853 * symbol into local .bss. If there is a copy_reloc to be 854 * performed, that should still occur against the WEAK symbol. 855 */ 856 if ((ELF_ST_BIND(sdp->sd_sym->st_info) == STB_WEAK) || 857 (sdp->sd_flags & FLG_SY_WEAKDEF)) 858 rsp->rel_usym = _sdp; 859 } else 860 _sdp = 0; 861 862 /* 863 * If the reference is to an object then allocate space for the object 864 * within the executables .bss. Relocations will now be performed from 865 * this new location. If the original shared objects data is 866 * initialized, then generate a copy relocation that will copy the data 867 * to the executables .bss at runtime. 868 */ 869 if (!(rsp->rel_usym->sd_flags & FLG_SY_MVTOCOMM)) { 870 Word rtype = rsp->rel_rtype; 871 Copy_rel cr; 872 873 /* 874 * Indicate that the symbol(s) against which we're relocating 875 * have been moved to the executables common. Also, insure that 876 * the symbol(s) remain marked as global, as the shared object 877 * from which they are copied must be able to relocate to the 878 * new common location within the executable. 879 * 880 * Note that even though a new symbol has been generated in the 881 * output files' .bss, the symbol must remain REF_DYN_NEED and 882 * not be promoted to REF_REL_NEED. sym_validate() still needs 883 * to carry out a number of checks against the symbols binding 884 * that are triggered by the REF_DYN_NEED state. 885 */ 886 sdp->sd_flags |= 887 (FLG_SY_MVTOCOMM | FLG_SY_DEFAULT | FLG_SY_EXPDEF); 888 sdp->sd_flags &= ~MSK_SY_LOCAL; 889 sdp->sd_sym->st_other &= ~MSK_SYM_VISIBILITY; 890 if (_sdp) { 891 _sdp->sd_flags |= (FLG_SY_MVTOCOMM | 892 FLG_SY_DEFAULT | FLG_SY_EXPDEF); 893 _sdp->sd_flags &= ~MSK_SY_LOCAL; 894 _sdp->sd_sym->st_other &= ~MSK_SYM_VISIBILITY; 895 896 /* 897 * Make sure the symbol has a reference in case of any 898 * error diagnostics against it (perhaps this belongs 899 * to a version that isn't allowable for this build). 900 * The resulting diagnostic (see sym_undef_entry()) 901 * might seem a little bogus, as the symbol hasn't 902 * really been referenced by this file, but has been 903 * promoted as a consequence of its alias reference. 904 */ 905 if (!(_sdp->sd_aux->sa_rfile)) 906 _sdp->sd_aux->sa_rfile = sdp->sd_aux->sa_rfile; 907 } 908 909 /* 910 * Assign the symbol to the bss and insure sufficient alignment 911 * (we don't know the real alignment so we have to make the 912 * worst case guess). 913 */ 914 _sdp = rsp->rel_usym; 915 stval = _sdp->sd_sym->st_value; 916 if (ld_sym_copy(_sdp) == S_ERROR) 917 return (S_ERROR); 918 _sdp->sd_shndx = _sdp->sd_sym->st_shndx = SHN_COMMON; 919 _sdp->sd_flags |= FLG_SY_SPECSEC; 920 _sdp->sd_sym->st_value = 921 (_sdp->sd_sym->st_size < (ld_targ.t_m.m_word_align * 2)) ? 922 ld_targ.t_m.m_word_align : ld_targ.t_m.m_word_align * 2; 923 924 /* 925 * Whether or not the symbol references initialized data we 926 * generate a copy relocation - this differs from the past 927 * where we would not create the COPY_RELOC if we were binding 928 * against .bss. This is done for *two* reasons. 929 * 930 * - If the symbol in the shared object changes to a 931 * initialized data - we need the COPY to pick it up. 932 * - Without the COPY RELOC we can't tell that the symbol 933 * from the COPY'd object has been moved and all bindings 934 * to it should bind here. 935 * 936 * Keep this symbol in the copy relocation list to check the 937 * validity later. 938 */ 939 cr.c_sdp = _sdp; 940 cr.c_val = stval; 941 if (alist_append(&ofl->ofl_copyrels, &cr, sizeof (Copy_rel), 942 AL_CNT_OFL_COPYRELS) == NULL) 943 return (S_ERROR); 944 945 rsp->rel_rtype = ld_targ.t_m.m_r_copy; 946 if ((*ld_targ.t_mr.mr_add_outrel)(FLG_REL_BSS, rsp, ofl) == 947 S_ERROR) 948 return (S_ERROR); 949 rsp->rel_rtype = rtype; 950 951 /* 952 * If this symbol is a protected symbol, warn it. 953 */ 954 if (_sdp->sd_flags & FLG_SY_PROT) { 955 Conv_inv_buf_t inv_buf; 956 957 eprintf(ofl->ofl_lml, ERR_WARNING, 958 MSG_INTL(MSG_REL_COPY), 959 conv_reloc_type(_sdp->sd_file->ifl_ehdr->e_machine, 960 ld_targ.t_m.m_r_copy, 0, &inv_buf), 961 _sdp->sd_file->ifl_name, _sdp->sd_name); 962 } 963 DBG_CALL(Dbg_syms_reloc(ofl, sdp)); 964 } 965 return (ld_add_actrel(NULL, rsp, ofl)); 966 } 967 968 /* 969 * All relocations should have been handled by the other routines. This 970 * routine is here as a catch all, if we do enter it we've goofed - but 971 * we'll try and do the best we can. 972 */ 973 static uintptr_t 974 reloc_generic(Rel_desc *rsp, Ofl_desc *ofl) 975 { 976 Ifl_desc *ifl = rsp->rel_isdesc->is_file; 977 Conv_inv_buf_t inv_buf; 978 979 eprintf(ofl->ofl_lml, ERR_WARNING, MSG_INTL(MSG_REL_UNEXPREL), 980 conv_reloc_type(ifl->ifl_ehdr->e_machine, rsp->rel_rtype, 981 0, &inv_buf), ifl->ifl_name, demangle(rsp->rel_sname)); 982 983 /* 984 * If building a shared object then put the relocation off 985 * until runtime. 986 */ 987 if (ofl->ofl_flags & FLG_OF_SHAROBJ) 988 return ((*ld_targ.t_mr.mr_add_outrel)(NULL, rsp, ofl)); 989 990 /* 991 * Otherwise process relocation now. 992 */ 993 return (ld_add_actrel(NULL, rsp, ofl)); 994 } 995 996 /* 997 * Process relocations when building a relocatable object. Typically, there 998 * aren't many relocations that can be caught at this point, most are simply 999 * passed through to the output relocatable object. 1000 */ 1001 static uintptr_t 1002 reloc_relobj(Boolean local, Rel_desc *rsp, Ofl_desc *ofl) 1003 { 1004 Word rtype = rsp->rel_rtype; 1005 Sym_desc *sdp = rsp->rel_sym; 1006 Is_desc *isp = rsp->rel_isdesc; 1007 Word oflags = NULL; 1008 1009 /* 1010 * Determine if we can do any relocations at this point. We can if: 1011 * 1012 * this is local_symbol and a non-GOT relocation, and 1013 * the relocation is pc-relative, and 1014 * the relocation is against a symbol in same section 1015 */ 1016 if (local && !IS_GOT_RELATIVE(rtype) && 1017 !IS_GOT_BASED(rtype) && !IS_GOT_PC(rtype) && 1018 IS_PC_RELATIVE(rtype) && 1019 ((sdp->sd_isc) && (sdp->sd_isc->is_osdesc == isp->is_osdesc))) 1020 return (ld_add_actrel(NULL, rsp, ofl)); 1021 1022 /* 1023 * If -zredlocsym is in effect, translate all local symbol relocations 1024 * to be against section symbols, since section symbols are the only 1025 * local symbols which will be added to the .symtab. 1026 */ 1027 if (local && (((ofl->ofl_flags & FLG_OF_REDLSYM) && 1028 (ELF_ST_BIND(sdp->sd_sym->st_info) == STB_LOCAL)) || 1029 ((sdp->sd_flags & FLG_SY_ELIM) && 1030 (ofl->ofl_flags & FLG_OF_PROCRED)))) { 1031 /* 1032 * But if this is PIC code, don't allow it for now. 1033 */ 1034 if (IS_GOT_RELATIVE(rsp->rel_rtype)) { 1035 Ifl_desc *ifl = rsp->rel_isdesc->is_file; 1036 Conv_inv_buf_t inv_buf; 1037 1038 eprintf(ofl->ofl_lml, ERR_FATAL, 1039 MSG_INTL(MSG_REL_PICREDLOC), 1040 demangle(rsp->rel_sname), ifl->ifl_name, 1041 conv_reloc_type(ifl->ifl_ehdr->e_machine, 1042 rsp->rel_rtype, 0, &inv_buf)); 1043 return (S_ERROR); 1044 } 1045 1046 /* 1047 * Indicate that this relocation should be processed the same 1048 * as a section symbol. For RELA, indicate that the addend 1049 * also needs to be applied to this relocation. 1050 */ 1051 if ((rsp->rel_flags & FLG_REL_RELA) == FLG_REL_RELA) 1052 oflags = FLG_REL_SCNNDX | FLG_REL_ADVAL; 1053 else 1054 oflags = FLG_REL_SCNNDX; 1055 } 1056 1057 if ((rsp->rel_flags & FLG_REL_RELA) == 0) { 1058 /* 1059 * Intel (Rel) relocations do not contain an addend. Any 1060 * addend is contained within the file at the location 1061 * identified by the relocation offset. Therefore, if we're 1062 * processing a section symbol, or a -zredlocsym relocation 1063 * (that basically transforms a local symbol reference into 1064 * a section reference), perform an active relocation to 1065 * propagate any addend. 1066 */ 1067 if ((ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) || 1068 (oflags == FLG_REL_SCNNDX)) 1069 if (ld_add_actrel(NULL, rsp, ofl) == S_ERROR) 1070 return (S_ERROR); 1071 } 1072 return ((*ld_targ.t_mr.mr_add_outrel)(oflags, rsp, ofl)); 1073 } 1074 1075 /* 1076 * Perform any generic TLS validations before passing control to machine 1077 * specific routines. At this point we know we are dealing with an executable 1078 * or shared object - relocatable objects have already been processed. 1079 */ 1080 static uintptr_t 1081 reloc_TLS(Boolean local, Rel_desc *rsp, Ofl_desc *ofl) 1082 { 1083 Word rtype = rsp->rel_rtype; 1084 ofl_flag_t flags = ofl->ofl_flags; 1085 Ifl_desc *ifl = rsp->rel_isdesc->is_file; 1086 Half mach = ifl->ifl_ehdr->e_machine; 1087 Sym_desc *sdp = rsp->rel_sym; 1088 unsigned char type; 1089 Conv_inv_buf_t inv_buf1, inv_buf2; 1090 1091 /* 1092 * All TLS relocations are illegal in a static executable. 1093 */ 1094 if (OFL_IS_STATIC_EXEC(ofl)) { 1095 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_TLSSTAT), 1096 conv_reloc_type(mach, rtype, 0, &inv_buf1), ifl->ifl_name, 1097 demangle(rsp->rel_sname)); 1098 return (S_ERROR); 1099 } 1100 1101 /* 1102 * Any TLS relocation must be against a STT_TLS symbol, all others 1103 * are illegal. 1104 */ 1105 if ((type = ELF_ST_TYPE(sdp->sd_sym->st_info)) != STT_TLS) { 1106 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_TLSBADSYM), 1107 conv_reloc_type(mach, rtype, 0, &inv_buf1), ifl->ifl_name, 1108 demangle(rsp->rel_sname), 1109 conv_sym_info_type(mach, type, 0, &inv_buf2)); 1110 return (S_ERROR); 1111 } 1112 1113 /* 1114 * A dynamic executable can not use the LD or LE reference models to 1115 * reference an external symbol. A shared object can not use the LD 1116 * reference model to reference an external symbol. 1117 */ 1118 if (!local && (IS_TLS_LD(rtype) || 1119 ((flags & FLG_OF_EXEC) && IS_TLS_LE(rtype)))) { 1120 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_TLSBND), 1121 conv_reloc_type(mach, rtype, 0, &inv_buf1), ifl->ifl_name, 1122 demangle(rsp->rel_sname), sdp->sd_file->ifl_name); 1123 return (S_ERROR); 1124 } 1125 1126 /* 1127 * The TLS LE model is only allowed for dynamic executables. The TLS IE 1128 * model is allowed for shared objects, but this model has restrictions. 1129 * This model can only be used freely in dependencies that are loaded 1130 * immediately as part of process initialization. However, during the 1131 * initial runtime handshake with libc that establishes the thread 1132 * pointer, a small backup TLS reservation is created. This area can 1133 * be used by objects that are loaded after threads are initialized. 1134 * However, this area is limited in size and may have already been 1135 * used. This area is intended for specialized applications, and does 1136 * not provide the degree of flexibility dynamic TLS can offer. Under 1137 * -z verbose indicate this restriction to the user. 1138 */ 1139 if ((flags & FLG_OF_EXEC) == 0) { 1140 if (IS_TLS_LE(rtype)) { 1141 eprintf(ofl->ofl_lml, ERR_FATAL, 1142 MSG_INTL(MSG_REL_TLSLE), 1143 conv_reloc_type(mach, rtype, 0, &inv_buf1), 1144 ifl->ifl_name, demangle(rsp->rel_sname)); 1145 return (S_ERROR); 1146 1147 } else if ((IS_TLS_IE(rtype)) && 1148 (flags & FLG_OF_VERBOSE)) { 1149 eprintf(ofl->ofl_lml, ERR_WARNING, 1150 MSG_INTL(MSG_REL_TLSIE), 1151 conv_reloc_type(mach, rtype, 0, &inv_buf1), 1152 ifl->ifl_name, demangle(rsp->rel_sname)); 1153 } 1154 } 1155 1156 return ((*ld_targ.t_mr.mr_reloc_TLS)(local, rsp, ofl)); 1157 } 1158 1159 uintptr_t 1160 ld_process_sym_reloc(Ofl_desc *ofl, Rel_desc *reld, Rel *reloc, Is_desc *isp, 1161 const char *isname, Word isscnndx) 1162 { 1163 Word rtype = reld->rel_rtype; 1164 ofl_flag_t flags = ofl->ofl_flags; 1165 Sym_desc *sdp = reld->rel_sym; 1166 Sym_aux *sap; 1167 Boolean local; 1168 Conv_inv_buf_t inv_buf; 1169 1170 DBG_CALL(Dbg_reloc_in(ofl->ofl_lml, ELF_DBG_LD, ld_targ.t_m.m_mach, 1171 ld_targ.t_m.m_rel_sht_type, (void *)reloc, isname, isscnndx, 1172 reld->rel_sname)); 1173 1174 /* 1175 * Indicate this symbol is being used for relocation and therefore must 1176 * have its output address updated accordingly (refer to update_osym()). 1177 */ 1178 sdp->sd_flags |= FLG_SY_UPREQD; 1179 1180 /* 1181 * Indicate the section this symbol is defined in has been referenced, 1182 * therefor it *is not* a candidate for elimination. 1183 */ 1184 if (sdp->sd_isc) { 1185 sdp->sd_isc->is_flags |= FLG_IS_SECTREF; 1186 sdp->sd_isc->is_file->ifl_flags |= FLG_IF_FILEREF; 1187 } 1188 1189 reld->rel_usym = sdp; 1190 1191 /* 1192 * Determine if this symbol is actually an alias to another symbol. If 1193 * so, and the alias is not REF_DYN_SEEN, set rel_usym to point to the 1194 * weak symbols strong counter-part. The one exception is if the 1195 * FLG_SY_MVTOCOMM flag is set on the weak symbol. If this is the case, 1196 * the strong is only here because of its promotion, and the weak symbol 1197 * should still be used for the relocation reference (see reloc_exec()). 1198 */ 1199 sap = sdp->sd_aux; 1200 if (sap && sap->sa_linkndx && 1201 ((ELF_ST_BIND(sdp->sd_sym->st_info) == STB_WEAK) || 1202 (sdp->sd_flags & FLG_SY_WEAKDEF)) && 1203 (!(sdp->sd_flags & FLG_SY_MVTOCOMM))) { 1204 Sym_desc * _sdp; 1205 1206 _sdp = sdp->sd_file->ifl_oldndx[sap->sa_linkndx]; 1207 if (_sdp->sd_ref != REF_DYN_SEEN) 1208 reld->rel_usym = _sdp; 1209 } 1210 1211 /* 1212 * Determine whether this symbol should be bound locally or not. 1213 * Symbols are bound locally if one of the following is true: 1214 * 1215 * - the symbol is of type STB_LOCAL. 1216 * 1217 * - the output image is not a relocatable object and the relocation 1218 * is relative to the .got. 1219 * 1220 * - the section being relocated is of type SHT_SUNW_dof. These 1221 * sections must be bound to the functions in the containing 1222 * object and can not be interposed upon. 1223 * 1224 * - the symbol has been reduced (scoped to a local or symbolic) and 1225 * reductions are being processed. 1226 * 1227 * - the -Bsymbolic flag is in use when building a shared object, 1228 * and the symbol hasn't explicitly been defined as nodirect. 1229 * 1230 * - an executable (fixed address) is being created, and the symbol 1231 * is defined in the executable. 1232 * 1233 * - the relocation is against a segment which will not be loaded 1234 * into memory. In this case, the relocation must be resolved 1235 * now, as ld.so.1 can not process relocations against unmapped 1236 * segments. 1237 */ 1238 local = FALSE; 1239 if (ELF_ST_BIND(sdp->sd_sym->st_info) == STB_LOCAL) { 1240 local = TRUE; 1241 } else if (!(reld->rel_flags & FLG_REL_LOAD)) { 1242 local = TRUE; 1243 } else if (sdp->sd_sym->st_shndx != SHN_UNDEF) { 1244 if (reld->rel_isdesc && 1245 reld->rel_isdesc->is_shdr->sh_type == SHT_SUNW_dof) { 1246 local = TRUE; 1247 } else if (!(flags & FLG_OF_RELOBJ) && 1248 (IS_LOCALBND(rtype) || IS_SEG_RELATIVE(rtype))) { 1249 local = TRUE; 1250 } else if (sdp->sd_ref == REF_REL_NEED) { 1251 /* 1252 * Global symbols may have been individually reduced in 1253 * scope. If the whole object is to be self contained, 1254 * such as when generating an executable or a symbolic 1255 * shared object, make sure all relocation symbol 1256 * references (sections too) are treated locally. Note, 1257 * explicit no-direct symbols should not be bound to 1258 * locally. 1259 */ 1260 if ((sdp->sd_flags & 1261 (FLG_SY_HIDDEN | FLG_SY_PROTECT))) 1262 local = TRUE; 1263 else if ((flags & FLG_OF_EXEC) || 1264 ((flags & FLG_OF_SYMBOLIC) && 1265 ((sdp->sd_flags & FLG_SY_NDIR) == 0))) { 1266 local = TRUE; 1267 } 1268 } 1269 } 1270 1271 /* 1272 * If this is a PC_RELATIVE relocation, the relocation could be 1273 * compromised if the relocated address is later used as a copy 1274 * relocated symbol (PSARC 1999/636, bugid 4187211). Scan the input 1275 * files symbol table to cross reference this relocation offset. 1276 */ 1277 if ((ofl->ofl_flags & FLG_OF_SHAROBJ) && 1278 IS_PC_RELATIVE(rtype) && 1279 (IS_GOT_PC(rtype) == 0) && 1280 (IS_PLT(rtype) == 0)) { 1281 if (disp_inspect(ofl, reld, local) == S_ERROR) 1282 return (S_ERROR); 1283 } 1284 1285 /* 1286 * GOT based relocations must bind to the object being built - since 1287 * they are relevant to the current GOT. If not building a relocatable 1288 * object - give a appropriate error message. 1289 */ 1290 if (!local && !(flags & FLG_OF_RELOBJ) && 1291 IS_GOT_BASED(rtype)) { 1292 Ifl_desc *ifl = reld->rel_isdesc->is_file; 1293 1294 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_BADGOTBASED), 1295 conv_reloc_type(ifl->ifl_ehdr->e_machine, rtype, 1296 0, &inv_buf), ifl->ifl_name, demangle(sdp->sd_name)); 1297 return (S_ERROR); 1298 } 1299 1300 /* 1301 * TLS symbols can only have TLS relocations. 1302 */ 1303 if ((ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_TLS) && 1304 (IS_TLS_INS(rtype) == 0)) { 1305 /* 1306 * The above test is relaxed if the target section is 1307 * non-allocable. 1308 */ 1309 if (reld->rel_osdesc->os_shdr->sh_flags & SHF_ALLOC) { 1310 Ifl_desc *ifl = reld->rel_isdesc->is_file; 1311 1312 eprintf(ofl->ofl_lml, ERR_FATAL, 1313 MSG_INTL(MSG_REL_BADTLS), 1314 conv_reloc_type(ifl->ifl_ehdr->e_machine, 1315 rtype, 0, &inv_buf), ifl->ifl_name, 1316 demangle(sdp->sd_name)); 1317 return (S_ERROR); 1318 } 1319 } 1320 1321 /* 1322 * Select the relocation to perform. 1323 */ 1324 if (IS_REGISTER(rtype)) { 1325 if (ld_targ.t_mr.mr_reloc_register == NULL) { 1326 eprintf(ofl->ofl_lml, ERR_FATAL, 1327 MSG_INTL(MSG_REL_NOREG)); 1328 return (S_ERROR); 1329 } 1330 return ((*ld_targ.t_mr.mr_reloc_register)(reld, isp, ofl)); 1331 } 1332 1333 if (flags & FLG_OF_RELOBJ) 1334 return (reloc_relobj(local, reld, ofl)); 1335 1336 if (IS_TLS_INS(rtype)) 1337 return (reloc_TLS(local, reld, ofl)); 1338 1339 if (IS_GOT_OPINS(rtype)) { 1340 if (ld_targ.t_mr.mr_reloc_GOTOP == NULL) { 1341 assert(0); 1342 return (S_ERROR); 1343 } 1344 return ((*ld_targ.t_mr.mr_reloc_GOTOP)(local, reld, ofl)); 1345 } 1346 1347 if (IS_GOT_RELATIVE(rtype)) 1348 return (ld_reloc_GOT_relative(local, reld, ofl)); 1349 1350 if (local) 1351 return ((*ld_targ.t_mr.mr_reloc_local)(reld, ofl)); 1352 1353 if (IS_PLT(rtype) && ((flags & FLG_OF_BFLAG) == 0)) 1354 return (ld_reloc_plt(reld, ofl)); 1355 1356 if ((sdp->sd_ref == REF_REL_NEED) || 1357 (flags & FLG_OF_BFLAG) || (flags & FLG_OF_SHAROBJ) || 1358 (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_NOTYPE)) 1359 return ((*ld_targ.t_mr.mr_add_outrel)(NULL, reld, ofl)); 1360 1361 if (sdp->sd_ref == REF_DYN_NEED) 1362 return (reloc_exec(reld, ofl)); 1363 1364 /* 1365 * IS_NOT_REL(rtype) 1366 */ 1367 return (reloc_generic(reld, ofl)); 1368 } 1369 1370 /* 1371 * Given a relocation that references a local symbol from a discarded COMDAT 1372 * section, replace the symbol with the corresponding symbol from the section 1373 * that was kept. 1374 * 1375 * entry: 1376 * reld - Relocation 1377 * sdp - Symbol to be replaced. Must be a local symbol (STB_LOCAL). 1378 * reject - Address of variable to receive rejection code 1379 * if no replacement symbol is found. 1380 * 1381 * exit: 1382 * Returns address of replacement symbol descriptor if one was 1383 * found, and NULL otherwise. The result is also cached in 1384 * ofl->ofl_sr_cache as an optimization to speed following calls 1385 * for the same value of sdp. 1386 * 1387 * On success (non-NULL result), *reject is set to RLXREL_REJ_NONE. 1388 * On failure (NULL result), *reject is filled in with a code 1389 * describing the underlying reason. 1390 * 1391 * note: 1392 * The word "COMDAT" is used to refer to actual COMDAT sections, COMDAT 1393 * groups tied together with an SHF_GROUP section, and .gnu.linkonce 1394 * sections which provide a simplified COMDAT requirement. COMDAT 1395 * sections are identified with the FLG_IS_COMDAT section flag. 1396 * 1397 * In principle, this sort of sloppy relocation remapping is 1398 * a questionable practice. All self-referential sections should 1399 * be in a common SHF_GROUP so that they are all kept or removed 1400 * together. The problem is that there is no way to ensure that the 1401 * two sections are similar enough that the replacement section will 1402 * really supply the correct information. However, we see a couple of 1403 * situations where it is useful to do this: (1) Older Sun C compilers 1404 * generated DWARF sections that would refer to one of the COMDAT 1405 * sections, and (2) gcc, when its GNU linkonce COMDAT feature is enabled. 1406 * It turns out that the GNU ld does these sloppy remappings. 1407 * 1408 * The GNU ld takes an approach that hard wires special section 1409 * names and treats them specially. We avoid that practice and 1410 * try to get the necessary work done relying only on the ELF 1411 * attributes of the sections and symbols involved. This means 1412 * that our heuristic is somewhat different than theirs, but the 1413 * end result is close enough to solve the same problem. 1414 * 1415 * gcc is in the process of converting to SHF_GROUP. This will 1416 * eventually phase out the need for sloppy relocations, and 1417 * then this logic won't be needed. In the meantime, relaxed relocation 1418 * processing allows us to interoperate. 1419 */ 1420 static Sym_desc * 1421 sloppy_comdat_reloc(Ofl_desc *ofl, Rel_desc *reld, Sym_desc *sdp, 1422 Rlxrel_rej *reject) 1423 { 1424 Is_desc *rep_isp; 1425 Sym *sym, *rep_sym; 1426 Is_desc *isp; 1427 Ifl_desc *ifl; 1428 Conv_inv_buf_t inv_buf; 1429 Word scnndx, symscnt; 1430 Sym_desc **oldndx, *rep_sdp; 1431 const char *is_name; 1432 1433 1434 /* 1435 * Sloppy relocations are never applied to .eh_frame or 1436 * .gcc_except_table sections. The entries in these sections 1437 * for discarded sections are better left uninitialized. 1438 * 1439 * We match these sections by name, because on most platforms they 1440 * are SHT_PROGBITS, and cannot be identified otherwise. On amd64 1441 * architectures, .eh_frame is SHT_AMD64_UNWIND, but that is ambiguous 1442 * (.eh_frame_hdr is also SHT_AMD64_UNWIND), so we still match it by 1443 * name. 1444 */ 1445 is_name = reld->rel_isdesc->is_name; 1446 if (((is_name[1] == 'e') && 1447 (strcmp(is_name, MSG_ORIG(MSG_SCN_EHFRAME)) == 0)) || 1448 ((is_name[1] == 'g') && 1449 (strcmp(is_name, MSG_ORIG(MSG_SCN_GCC_X_TBL)) == 0))) { 1450 *reject = RLXREL_REJ_TARGET; 1451 return (NULL); 1452 } 1453 1454 /* 1455 * If we looked up the same symbol on the previous call, we can 1456 * return the cached value. 1457 */ 1458 if (sdp == ofl->ofl_sr_cache.sr_osdp) { 1459 *reject = ofl->ofl_sr_cache.sr_rej; 1460 return (ofl->ofl_sr_cache.sr_rsdp); 1461 } 1462 1463 ofl->ofl_sr_cache.sr_osdp = sdp; 1464 sym = sdp->sd_sym; 1465 isp = sdp->sd_isc; 1466 ifl = sdp->sd_file; 1467 1468 /* 1469 * When a COMDAT section is discarded in favor of another COMDAT 1470 * section, the replacement is recorded in its section descriptor 1471 * (is_comdatkeep). We must validate the replacement before using 1472 * it. The replacement section must: 1473 * - Not have been discarded 1474 * - Have the same size (*) 1475 * - Have the same section type 1476 * - Have the same SHF_GROUP flag setting (either on or off) 1477 * - Must be a COMDAT section of one form or the other. 1478 * 1479 * (*) One might imagine that the replacement section could be 1480 * larger than the original, rather than the exact size. However, 1481 * we have verified that this is the same policy used by the GNU 1482 * ld. If the sections are not the same size, the chance of them 1483 * being interchangeable drops significantly. 1484 */ 1485 if (((rep_isp = isp->is_comdatkeep) == NULL) || 1486 ((rep_isp->is_flags & FLG_IS_DISCARD) != 0) || 1487 ((rep_isp->is_flags & FLG_IS_COMDAT) == 0) || 1488 (isp->is_indata->d_size != rep_isp->is_indata->d_size) || 1489 (isp->is_shdr->sh_type != rep_isp->is_shdr->sh_type) || 1490 ((isp->is_shdr->sh_flags & SHF_GROUP) != 1491 (rep_isp->is_shdr->sh_flags & SHF_GROUP))) { 1492 *reject = ofl->ofl_sr_cache.sr_rej = RLXREL_REJ_SECTION; 1493 return (ofl->ofl_sr_cache.sr_rsdp = NULL); 1494 } 1495 1496 /* 1497 * We found the kept COMDAT section. Now, look at all of the 1498 * symbols from the input file that contains it to find the 1499 * symbol that corresponds to the one we started with: 1500 * - Hasn't been discarded 1501 * - Has section index of kept section 1502 * - If one symbol has a name, the other must have 1503 * the same name. The st_name field of a symbol 1504 * is 0 if there is no name, and is a string 1505 * table offset otherwise. The string table 1506 * offsets may well not agree --- it is the 1507 * actual string that matters. 1508 * - Type and binding attributes match (st_info) 1509 * - Values match (st_value) 1510 * - Sizes match (st_size) 1511 * - Visibility matches (st_other) 1512 */ 1513 scnndx = rep_isp->is_scnndx; 1514 oldndx = rep_isp->is_file->ifl_oldndx; 1515 symscnt = rep_isp->is_file->ifl_symscnt; 1516 while (symscnt--) { 1517 rep_sdp = *oldndx++; 1518 if ((rep_sdp == NULL) || (rep_sdp->sd_flags & FLG_SY_ISDISC) || 1519 ((rep_sym = rep_sdp->sd_sym)->st_shndx != scnndx) || 1520 ((sym->st_name == 0) != (rep_sym->st_name == 0)) || 1521 ((sym->st_name != 0) && 1522 (strcmp(sdp->sd_name, rep_sdp->sd_name) != 0)) || 1523 (sym->st_info != rep_sym->st_info) || 1524 (sym->st_value != rep_sym->st_value) || 1525 (sym->st_size != rep_sym->st_size) || 1526 (sym->st_other != rep_sym->st_other)) 1527 continue; 1528 1529 1530 if (ofl->ofl_flags & FLG_OF_VERBOSE) { 1531 if (sym->st_name != 0) { 1532 eprintf(ofl->ofl_lml, ERR_WARNING, 1533 MSG_INTL(MSG_REL_SLOPCDATNAM), 1534 conv_reloc_type(ifl->ifl_ehdr->e_machine, 1535 reld->rel_rtype, 0, &inv_buf), 1536 ifl->ifl_name, 1537 EC_WORD(reld->rel_isdesc->is_scnndx), 1538 reld->rel_isdesc->is_name, 1539 rep_sdp->sd_name, 1540 EC_WORD(isp->is_scnndx), isp->is_name, 1541 rep_sdp->sd_file->ifl_name); 1542 } else { 1543 eprintf(ofl->ofl_lml, ERR_WARNING, 1544 MSG_INTL(MSG_REL_SLOPCDATNONAM), 1545 conv_reloc_type(ifl->ifl_ehdr->e_machine, 1546 reld->rel_rtype, 0, &inv_buf), 1547 ifl->ifl_name, 1548 EC_WORD(reld->rel_isdesc->is_scnndx), 1549 reld->rel_isdesc->is_name, 1550 EC_WORD(isp->is_scnndx), isp->is_name, 1551 rep_sdp->sd_file->ifl_name); 1552 } 1553 } 1554 DBG_CALL(Dbg_reloc_sloppycomdat(ofl->ofl_lml, rep_sdp)); 1555 *reject = ofl->ofl_sr_cache.sr_rej = RLXREL_REJ_NONE; 1556 return (ofl->ofl_sr_cache.sr_rsdp = rep_sdp); 1557 } 1558 1559 /* If didn't return above, we didn't find it */ 1560 *reject = ofl->ofl_sr_cache.sr_rej = RLXREL_REJ_SYMBOL; 1561 return (ofl->ofl_sr_cache.sr_rsdp = NULL); 1562 } 1563 1564 /* 1565 * Generate relocation descriptor and dispatch 1566 */ 1567 static uintptr_t 1568 process_reld(Ofl_desc *ofl, Is_desc *isp, Rel_desc *reld, Word rsndx, 1569 Rel *reloc) 1570 { 1571 Ifl_desc *ifl = isp->is_file; 1572 Word rtype = reld->rel_rtype; 1573 Sym_desc *sdp; 1574 Conv_inv_buf_t inv_buf; 1575 1576 /* 1577 * Make sure the relocation is in the valid range. 1578 */ 1579 if (rtype >= ld_targ.t_m.m_r_num) { 1580 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_INVALRELT), 1581 ifl->ifl_name, EC_WORD(isp->is_scnndx), isp->is_name, 1582 rtype); 1583 return (S_ERROR); 1584 } 1585 1586 ofl->ofl_entrelscnt++; 1587 1588 /* 1589 * Special case: a register symbol associated with symbol index 0 is 1590 * initialized (i.e., relocated) to a constant from the r_addend field 1591 * rather than from a symbol value. 1592 */ 1593 if (IS_REGISTER(rtype) && (rsndx == 0)) { 1594 reld->rel_sym = 0; 1595 reld->rel_sname = MSG_ORIG(MSG_STR_EMPTY); 1596 1597 DBG_CALL(Dbg_reloc_in(ofl->ofl_lml, ELF_DBG_LD, 1598 ld_targ.t_m.m_mach, isp->is_shdr->sh_type, 1599 (void *)reloc, isp->is_name, isp->is_scnndx, 1600 reld->rel_sname)); 1601 if (ld_targ.t_mr.mr_reloc_register == NULL) { 1602 eprintf(ofl->ofl_lml, ERR_FATAL, 1603 MSG_INTL(MSG_REL_NOREG)); 1604 return (S_ERROR); 1605 } 1606 return ((*ld_targ.t_mr.mr_reloc_register)(reld, isp, ofl)); 1607 } 1608 1609 /* 1610 * Come up with a descriptive name for the symbol: 1611 * - If it is a named symbol, use the name as is 1612 * - If it is an STT_SECTION symbol, generate a descriptive 1613 * string that incorporates the section name. 1614 * - Otherwise, supply an "unknown" string. 1615 * Note that bogus relocations can result in a null symbol descriptor 1616 * (sdp), the error condition should be caught below after determining 1617 * whether a valid symbol name exists. 1618 */ 1619 sdp = ifl->ifl_oldndx[rsndx]; 1620 if ((sdp != NULL) && sdp->sd_name && *sdp->sd_name) { 1621 reld->rel_sname = sdp->sd_name; 1622 } else if ((sdp != NULL) && 1623 (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) && 1624 (sdp->sd_isc != NULL) && (sdp->sd_isc->is_name != NULL)) { 1625 if ((reld->rel_sname = ld_stt_section_sym_name(sdp->sd_isc)) == 1626 NULL) 1627 return (S_ERROR); 1628 } else { 1629 static char *strunknown; 1630 1631 if (strunknown == 0) 1632 strunknown = (char *)MSG_INTL(MSG_STR_UNKNOWN); 1633 reld->rel_sname = strunknown; 1634 } 1635 1636 /* 1637 * If for some reason we have a null relocation record issue a 1638 * warning and continue (the compiler folks can get into this 1639 * state some time). Normal users should never see this error. 1640 */ 1641 if (rtype == ld_targ.t_m.m_r_none) { 1642 DBG_CALL(Dbg_reloc_in(ofl->ofl_lml, ELF_DBG_LD, 1643 ld_targ.t_m.m_mach, ld_targ.t_m.m_rel_sht_type, 1644 (void *)reloc, isp->is_name, isp->is_scnndx, 1645 reld->rel_sname)); 1646 eprintf(ofl->ofl_lml, ERR_WARNING, MSG_INTL(MSG_REL_NULL), 1647 ifl->ifl_name, EC_WORD(isp->is_scnndx), isp->is_name); 1648 return (1); 1649 } 1650 1651 if (((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) && 1652 IS_NOTSUP(rtype)) { 1653 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_NOTSUP), 1654 conv_reloc_type(ifl->ifl_ehdr->e_machine, rtype, 1655 0, &inv_buf), ifl->ifl_name, EC_WORD(isp->is_scnndx), 1656 isp->is_name); 1657 return (S_ERROR); 1658 } 1659 1660 /* 1661 * If we are here, we know that the relocation requires reference 1662 * symbol. If no symbol is assigned, this is a fatal error. 1663 */ 1664 if (sdp == NULL) { 1665 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_NOSYMBOL), 1666 conv_reloc_type(ifl->ifl_ehdr->e_machine, rtype, 1667 0, &inv_buf), ifl->ifl_name, EC_WORD(isp->is_scnndx), 1668 isp->is_name, EC_XWORD(reloc->r_offset)); 1669 return (S_ERROR); 1670 } 1671 1672 if (sdp->sd_flags & FLG_SY_IGNORE) 1673 return (1); 1674 1675 /* 1676 * If this symbol is part of a DISCARDED section attempt to find another 1677 * definition. 1678 */ 1679 if (sdp->sd_flags & FLG_SY_ISDISC) { 1680 Sym_desc *nsdp = NULL; 1681 Rlxrel_rej reject; 1682 1683 if (ELF_ST_BIND(sdp->sd_sym->st_info) == STB_LOCAL) { 1684 /* 1685 * If "-z relaxreloc", and the input section is COMDAT 1686 * that has been assigned to an output section, then 1687 * determine if this is a reference to a discarded 1688 * COMDAT section that can be replaced with a COMDAT 1689 * that has been kept. 1690 */ 1691 if ((ofl->ofl_flags1 & FLG_OF1_RLXREL) && 1692 sdp->sd_isc->is_osdesc && 1693 (sdp->sd_isc->is_flags & FLG_IS_COMDAT) && 1694 ((nsdp = sloppy_comdat_reloc(ofl, reld, 1695 sdp, &reject)) == NULL)) { 1696 Shdr *is_shdr = reld->rel_isdesc->is_shdr; 1697 1698 /* 1699 * A matching symbol was not found. We will 1700 * ignore this relocation. Determine whether 1701 * or not to issue a warning. 1702 * Warnings are always issued under -z verbose, 1703 * but otherwise, we will follow the lead of 1704 * the GNU ld and suppress them for certain 1705 * cases: 1706 * 1707 * - It is a non-allocable debug section. 1708 * The GNU ld tests for these by name, 1709 * but we are willing to extend it to 1710 * any non-allocable section. 1711 * - The target section is excluded from 1712 * sloppy relocations by policy. 1713 */ 1714 if (((ofl->ofl_flags & FLG_OF_VERBOSE) != 0) || 1715 ((is_shdr->sh_flags & SHF_ALLOC) && 1716 (reject != RLXREL_REJ_TARGET))) 1717 eprintf(ofl->ofl_lml, ERR_WARNING, 1718 MSG_INTL(MSG_REL_SLOPCDATNOSYM), 1719 conv_reloc_type( 1720 ifl->ifl_ehdr->e_machine, 1721 reld->rel_rtype, 0, &inv_buf), 1722 ifl->ifl_name, 1723 EC_WORD(isp->is_scnndx), 1724 isp->is_name, 1725 demangle(reld->rel_sname), 1726 EC_WORD(sdp->sd_isc->is_scnndx), 1727 sdp->sd_isc->is_name); 1728 return (1); 1729 } 1730 } else if (reld->rel_sname == sdp->sd_name) 1731 nsdp = ld_sym_find(sdp->sd_name, SYM_NOHASH, NULL, ofl); 1732 1733 if (nsdp == NULL) { 1734 eprintf(ofl->ofl_lml, ERR_FATAL, 1735 MSG_INTL(MSG_REL_SYMDISC), 1736 conv_reloc_type(ifl->ifl_ehdr->e_machine, 1737 reld->rel_rtype, 0, &inv_buf), ifl->ifl_name, 1738 EC_WORD(isp->is_scnndx), isp->is_name, 1739 demangle(reld->rel_sname), 1740 EC_WORD(sdp->sd_isc->is_scnndx), 1741 sdp->sd_isc->is_name); 1742 return (S_ERROR); 1743 } 1744 ifl->ifl_oldndx[rsndx] = sdp = nsdp; 1745 } 1746 1747 /* 1748 * If this is a global symbol, determine whether its visibility needs 1749 * adjusting. 1750 */ 1751 if (sdp->sd_aux && ((sdp->sd_flags & FLG_SY_VISIBLE) == 0)) 1752 ld_sym_adjust_vis(sdp, ofl); 1753 1754 /* 1755 * Ignore any relocation against a section that will not be in the 1756 * output file (has been stripped). 1757 */ 1758 if ((sdp->sd_isc == 0) && 1759 (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION)) 1760 return (1); 1761 1762 /* 1763 * If the input section exists, but the section has not been associated 1764 * to an output section, then this is a little suspicious. 1765 */ 1766 if (sdp->sd_isc && (sdp->sd_isc->is_osdesc == 0) && 1767 (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION)) { 1768 eprintf(ofl->ofl_lml, ERR_WARNING, MSG_INTL(MSG_RELINVSEC), 1769 conv_reloc_type(ifl->ifl_ehdr->e_machine, rtype, 1770 0, &inv_buf), ifl->ifl_name, EC_WORD(isp->is_scnndx), 1771 isp->is_name, EC_WORD(sdp->sd_isc->is_scnndx), 1772 sdp->sd_isc->is_name); 1773 return (1); 1774 } 1775 1776 /* 1777 * If the symbol for this relocation is invalid (which should have 1778 * generated a message during symbol processing), or the relocation 1779 * record's symbol reference is in any other way invalid, then it's 1780 * about time we gave up. 1781 */ 1782 if ((sdp->sd_flags & FLG_SY_INVALID) || (rsndx == 0) || 1783 (rsndx >= ifl->ifl_symscnt)) { 1784 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_UNKNWSYM), 1785 conv_reloc_type(ifl->ifl_ehdr->e_machine, rtype, 1786 0, &inv_buf), ifl->ifl_name, EC_WORD(isp->is_scnndx), 1787 isp->is_name, demangle(reld->rel_sname), 1788 EC_XWORD(reloc->r_offset), EC_WORD(rsndx)); 1789 return (S_ERROR); 1790 } 1791 1792 /* 1793 * Size relocations against section symbols are presently unsupported. 1794 * There is a question as to whether the input section size, or output 1795 * section size would be used. Until an explicit requirement is 1796 * established for either case, we'll punt. 1797 */ 1798 if (IS_SIZE(rtype) && 1799 (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION)) { 1800 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_UNSUPSIZE), 1801 conv_reloc_type(ifl->ifl_ehdr->e_machine, rtype, 1802 0, &inv_buf), ifl->ifl_name, EC_WORD(isp->is_scnndx), 1803 isp->is_name); 1804 return (S_ERROR); 1805 } 1806 1807 reld->rel_sym = sdp; 1808 return (ld_process_sym_reloc(ofl, reld, reloc, isp, isp->is_name, 1809 isp->is_scnndx)); 1810 } 1811 1812 static uintptr_t 1813 reloc_section(Ofl_desc *ofl, Is_desc *isect, Is_desc *rsect, Os_desc *osect) 1814 { 1815 Rel *rend; /* end of relocation section data */ 1816 Rel *reloc; /* current relocation entry */ 1817 Xword rsize; /* size of relocation section data */ 1818 Xword entsize; /* size of relocation entry */ 1819 Rel_desc reld; /* relocation descriptor */ 1820 Shdr * shdr; 1821 Word flags = 0; 1822 uintptr_t ret = 1; 1823 1824 shdr = rsect->is_shdr; 1825 rsize = shdr->sh_size; 1826 reloc = (Rel *)rsect->is_indata->d_buf; 1827 1828 /* 1829 * Decide entry size. 1830 */ 1831 if (((entsize = shdr->sh_entsize) == 0) || (entsize > rsize)) { 1832 if (shdr->sh_type == SHT_RELA) 1833 entsize = sizeof (Rela); 1834 else 1835 entsize = sizeof (Rel); 1836 } 1837 1838 /* 1839 * Build up the basic information in for the Rel_desc structure. 1840 */ 1841 reld.rel_osdesc = osect; 1842 reld.rel_isdesc = isect; 1843 reld.rel_move = 0; 1844 1845 if ((ofl->ofl_flags & FLG_OF_RELOBJ) || 1846 (osect && (osect->os_sgdesc->sg_phdr.p_type == PT_LOAD))) 1847 flags |= FLG_REL_LOAD; 1848 1849 if (shdr->sh_info == 0) 1850 flags |= FLG_REL_NOINFO; 1851 1852 DBG_CALL(Dbg_reloc_proc(ofl->ofl_lml, osect, isect, rsect)); 1853 1854 for (rend = (Rel *)((uintptr_t)reloc + (uintptr_t)rsize); 1855 reloc < rend; 1856 reloc = (Rel *)((uintptr_t)reloc + (uintptr_t)entsize)) { 1857 Word rsndx; 1858 1859 /* 1860 * Initialize the relocation record information and process 1861 * the individual relocation. Reinitialize the flags to 1862 * insure we don't carry any state over from the previous 1863 * relocation records processing. 1864 */ 1865 reld.rel_flags = flags; 1866 rsndx = (*ld_targ.t_mr.mr_init_rel)(&reld, (void *)reloc); 1867 1868 if (process_reld(ofl, rsect, &reld, rsndx, reloc) == S_ERROR) 1869 ret = S_ERROR; 1870 } 1871 return (ret); 1872 } 1873 1874 static uintptr_t 1875 reloc_segments(int wr_flag, Ofl_desc *ofl) 1876 { 1877 Aliste idx1; 1878 Sg_desc *sgp; 1879 Is_desc *isp; 1880 1881 for (APLIST_TRAVERSE(ofl->ofl_segs, idx1, sgp)) { 1882 Os_desc *osp; 1883 Aliste idx2; 1884 1885 if ((sgp->sg_phdr.p_flags & PF_W) != wr_flag) 1886 continue; 1887 1888 for (APLIST_TRAVERSE(sgp->sg_osdescs, idx2, osp)) { 1889 Is_desc *risp; 1890 Aliste idx3; 1891 1892 osp->os_szoutrels = 0; 1893 for (APLIST_TRAVERSE(osp->os_relisdescs, idx3, risp)) { 1894 Word indx; 1895 1896 /* 1897 * Determine the input section that this 1898 * relocation information refers to. 1899 */ 1900 indx = risp->is_shdr->sh_info; 1901 isp = risp->is_file->ifl_isdesc[indx]; 1902 1903 /* 1904 * Do not process relocations against sections 1905 * which are being discarded (COMDAT) 1906 */ 1907 if (isp->is_flags & FLG_IS_DISCARD) 1908 continue; 1909 1910 if (reloc_section(ofl, isp, risp, osp) == 1911 S_ERROR) 1912 return (S_ERROR); 1913 } 1914 1915 /* 1916 * Check for relocations against non-writable 1917 * allocatable sections. 1918 */ 1919 if (osp->os_szoutrels && 1920 (sgp->sg_phdr.p_type == PT_LOAD) && 1921 ((sgp->sg_phdr.p_flags & PF_W) == 0)) { 1922 ofl->ofl_flags |= FLG_OF_TEXTREL; 1923 ofl->ofl_dtflags |= DF_TEXTREL; 1924 } 1925 } 1926 } 1927 1928 return (1); 1929 } 1930 1931 /* 1932 * Move Section related function 1933 * Get move entry 1934 */ 1935 static Move * 1936 get_move_entry(Is_desc *rsect, Xword roffset) 1937 { 1938 Ifl_desc *ifile = rsect->is_file; 1939 Shdr *rshdr = rsect->is_shdr; 1940 Is_desc *misp; 1941 Shdr *mshdr; 1942 Xword midx; 1943 Move *mvp; 1944 1945 /* 1946 * Set info for the target move section 1947 */ 1948 misp = ifile->ifl_isdesc[rshdr->sh_info]; 1949 mshdr = misp->is_shdr; 1950 1951 if (mshdr->sh_entsize == 0) 1952 return (NULL); 1953 1954 /* 1955 * If this is an invalid entry, return NULL. 1956 */ 1957 midx = roffset / mshdr->sh_entsize; 1958 if ((midx * mshdr->sh_entsize) >= mshdr->sh_size) 1959 return (NULL); 1960 1961 mvp = (Move *)misp->is_indata->d_buf; 1962 mvp += midx; 1963 return (mvp); 1964 } 1965 1966 /* 1967 * Relocation against Move Table. 1968 */ 1969 static uintptr_t 1970 process_movereloc(Ofl_desc *ofl, Is_desc *rsect) 1971 { 1972 Ifl_desc *file = rsect->is_file; 1973 Rel *rend, *reloc; 1974 Xword rsize, entsize; 1975 Rel_desc reld; 1976 1977 rsize = rsect->is_shdr->sh_size; 1978 reloc = (Rel *)rsect->is_indata->d_buf; 1979 1980 /* 1981 * Decide entry size. 1982 */ 1983 entsize = rsect->is_shdr->sh_entsize; 1984 if ((entsize == 0) || 1985 (entsize > rsect->is_shdr->sh_size)) { 1986 if (rsect->is_shdr->sh_type == SHT_RELA) 1987 entsize = sizeof (Rela); 1988 else 1989 entsize = sizeof (Rel); 1990 } 1991 1992 /* 1993 * Go through the relocation entries. 1994 */ 1995 for (rend = (Rel *)((uintptr_t)reloc + (uintptr_t)rsize); 1996 reloc < rend; 1997 reloc = (Rel *)((uintptr_t)reloc + (uintptr_t)entsize)) { 1998 Sym_desc *psdp; 1999 Move *mvp; 2000 Word rsndx; 2001 2002 /* 2003 * Initialize the relocation record information. 2004 */ 2005 reld.rel_flags = FLG_REL_LOAD; 2006 rsndx = (*ld_targ.t_mr.mr_init_rel)(&reld, (void *)reloc); 2007 2008 if (((mvp = get_move_entry(rsect, reloc->r_offset)) == NULL) || 2009 ((reld.rel_move = libld_malloc(sizeof (Mv_reloc))) == NULL)) 2010 return (S_ERROR); 2011 2012 psdp = file->ifl_oldndx[ELF_M_SYM(mvp->m_info)]; 2013 reld.rel_move->mr_move = mvp; 2014 reld.rel_move->mr_sym = psdp; 2015 2016 if (psdp->sd_flags & FLG_SY_PAREXPN) { 2017 int _num, num = mvp->m_repeat; 2018 2019 reld.rel_osdesc = ofl->ofl_isparexpn->is_osdesc; 2020 reld.rel_isdesc = ofl->ofl_isparexpn; 2021 reld.rel_roffset = mvp->m_poffset; 2022 2023 for (_num = 0; _num < num; _num++) { 2024 reld.rel_roffset += 2025 /* LINTED */ 2026 (_num * ELF_M_SIZE(mvp->m_info)); 2027 2028 /* 2029 * Generate Reld 2030 */ 2031 if (process_reld(ofl, 2032 rsect, &reld, rsndx, reloc) == S_ERROR) 2033 return (S_ERROR); 2034 } 2035 } else { 2036 /* 2037 * Generate Reld 2038 */ 2039 reld.rel_flags |= FLG_REL_MOVETAB; 2040 reld.rel_osdesc = ofl->ofl_osmove; 2041 reld.rel_isdesc = ld_os_first_isdesc(ofl->ofl_osmove); 2042 2043 if (process_reld(ofl, 2044 rsect, &reld, rsndx, reloc) == S_ERROR) 2045 return (S_ERROR); 2046 } 2047 } 2048 return (1); 2049 } 2050 2051 /* 2052 * This function is similar to reloc_init(). 2053 * 2054 * This function is called when the SHT_SUNW_move table is expanded and there 2055 * are relocations against the SHT_SUNW_move section. 2056 */ 2057 static uintptr_t 2058 reloc_movesections(Ofl_desc *ofl) 2059 { 2060 Aliste idx; 2061 Is_desc *risp; 2062 uintptr_t ret = 1; 2063 2064 /* 2065 * Generate/Expand relocation entries 2066 */ 2067 for (APLIST_TRAVERSE(ofl->ofl_ismoverel, idx, risp)) { 2068 if (process_movereloc(ofl, risp) == S_ERROR) 2069 ret = S_ERROR; 2070 } 2071 2072 return (ret); 2073 } 2074 2075 /* 2076 * Count the number of output relocation entries, global offset table entries, 2077 * and procedure linkage table entries. This function searches the segment and 2078 * outsect lists and passes each input reloc section to process_reloc(). 2079 * It allocates space for any output relocations needed. And builds up 2080 * the relocation structures for later processing. 2081 */ 2082 uintptr_t 2083 ld_reloc_init(Ofl_desc *ofl) 2084 { 2085 Aliste idx; 2086 Is_desc *isp; 2087 Sym_desc *sdp; 2088 2089 DBG_CALL(Dbg_basic_collect(ofl->ofl_lml)); 2090 2091 /* 2092 * At this point we have finished processing all input symbols. Make 2093 * sure we add any absolute (internal) symbols before continuing with 2094 * any relocation processing. 2095 */ 2096 if (ld_sym_spec(ofl) == S_ERROR) 2097 return (S_ERROR); 2098 2099 ofl->ofl_gotcnt = ld_targ.t_m.m_got_xnumber; 2100 2101 /* 2102 * Process all of the relocations against NON-writable segments 2103 * followed by relocations against the writable segments. 2104 * 2105 * This separation is so that when the writable segments are processed 2106 * we know whether or not a COPYRELOC will be produced for any symbols. 2107 * If relocations aren't processed in this order, a COPYRELOC and a 2108 * regular relocation can be produced against the same symbol. The 2109 * regular relocation would be redundant. 2110 */ 2111 if (reloc_segments(0, ofl) == S_ERROR) 2112 return (S_ERROR); 2113 2114 if (reloc_segments(PF_W, ofl) == S_ERROR) 2115 return (S_ERROR); 2116 2117 /* 2118 * Process any extra relocations. These are relocation sections that 2119 * have a NULL sh_info. 2120 */ 2121 for (APLIST_TRAVERSE(ofl->ofl_extrarels, idx, isp)) { 2122 if (reloc_section(ofl, NULL, isp, NULL) == S_ERROR) 2123 return (S_ERROR); 2124 } 2125 2126 /* 2127 * If there were relocation against move table, 2128 * process the relocation sections. 2129 */ 2130 if (reloc_movesections(ofl) == S_ERROR) 2131 return (S_ERROR); 2132 2133 /* 2134 * Now all the relocations are pre-processed, 2135 * check the validity of copy relocations. 2136 */ 2137 if (ofl->ofl_copyrels) { 2138 Copy_rel *crp; 2139 2140 for (ALIST_TRAVERSE(ofl->ofl_copyrels, idx, crp)) { 2141 /* 2142 * If there were no displacement relocation 2143 * in this file, don't worry about it. 2144 */ 2145 if (crp->c_sdp->sd_file->ifl_flags & 2146 (FLG_IF_DISPPEND | FLG_IF_DISPDONE)) 2147 is_disp_copied(ofl, crp); 2148 } 2149 } 2150 2151 /* 2152 * GOT sections are created for dynamic executables and shared objects 2153 * if the FLG_OF_BLDGOT is set, or explicit reference has been made to 2154 * a GOT symbol. 2155 */ 2156 if (((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) && 2157 ((ofl->ofl_flags & FLG_OF_BLDGOT) || 2158 ((((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_GOFTBL), 2159 SYM_NOHASH, NULL, ofl)) != NULL) || 2160 ((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_GOFTBL_U), 2161 SYM_NOHASH, NULL, ofl)) != NULL)) && 2162 (sdp->sd_ref != REF_DYN_SEEN)))) { 2163 if (ld_make_got(ofl) == S_ERROR) 2164 return (S_ERROR); 2165 2166 /* Allocate the GOT if required by target */ 2167 if ((ld_targ.t_mr.mr_allocate_got != NULL) && 2168 ((*ld_targ.t_mr.mr_allocate_got)(ofl) == S_ERROR)) 2169 return (S_ERROR); 2170 } 2171 2172 return (1); 2173 } 2174 2175 /* 2176 * Simple comparison routine to be used by qsort() for 2177 * the sorting of the output relocation list. 2178 * 2179 * The reloc_compare() routine results in a relocation 2180 * table which is located on: 2181 * 2182 * file referenced (NEEDED NDX) 2183 * referenced symbol 2184 * relocation offset 2185 * 2186 * This provides the most efficient traversal of the relocation 2187 * table at run-time. 2188 */ 2189 static int 2190 reloc_compare(Reloc_list *i, Reloc_list *j) 2191 { 2192 2193 /* 2194 * first - sort on neededndx 2195 */ 2196 if (i->rl_key1 > j->rl_key1) 2197 return (1); 2198 if (i->rl_key1 < j->rl_key1) 2199 return (-1); 2200 2201 /* 2202 * Then sort on symbol 2203 */ 2204 if ((uintptr_t)i->rl_key2 > (uintptr_t)j->rl_key2) 2205 return (1); 2206 if ((uintptr_t)i->rl_key2 < (uintptr_t)j->rl_key2) 2207 return (-1); 2208 2209 /* 2210 * i->key2 == j->key2 2211 * 2212 * At this point we fall back to key2 (offsets) to 2213 * sort the output relocations. Ideally this will 2214 * make for the most efficient processing of these 2215 * relocations at run-time. 2216 */ 2217 if (i->rl_key3 > j->rl_key3) 2218 return (1); 2219 if (i->rl_key3 < j->rl_key3) 2220 return (-1); 2221 return (0); 2222 } 2223 2224 static uintptr_t 2225 do_sorted_outrelocs(Ofl_desc *ofl) 2226 { 2227 Rel_desc *orsp; 2228 Rel_cache *rcp; 2229 Aliste idx; 2230 Reloc_list *sorted_list; 2231 Word index = 0; 2232 int debug = 0; 2233 uintptr_t error = 1; 2234 2235 if ((sorted_list = libld_malloc((size_t)(sizeof (Reloc_list) * 2236 ofl->ofl_reloccnt))) == NULL) 2237 return (S_ERROR); 2238 2239 /* 2240 * All but the PLT output relocations are sorted in the output file 2241 * based upon their sym_desc. By doing this multiple relocations 2242 * against the same symbol are grouped together, thus when the object 2243 * is later relocated by ld.so.1 it will take advantage of the symbol 2244 * cache that ld.so.1 has. This can significantly reduce the runtime 2245 * relocation cost of a dynamic object. 2246 * 2247 * PLT relocations are not sorted because the order of the PLT 2248 * relocations is used by ld.so.1 to determine what symbol a PLT 2249 * relocation is against. 2250 */ 2251 for (APLIST_TRAVERSE(ofl->ofl_outrels, idx, rcp)) { 2252 /*LINTED*/ 2253 for (orsp = (Rel_desc *)(rcp + 1); 2254 orsp < rcp->rc_free; orsp++) { 2255 if (debug == 0) { 2256 DBG_CALL(Dbg_reloc_dooutrel(ofl->ofl_lml, 2257 ld_targ.t_m.m_rel_sht_type)); 2258 debug = 1; 2259 } 2260 2261 /* 2262 * If it's a PLT relocation we output it now in the 2263 * order that it was originally processed. 2264 */ 2265 if (orsp->rel_flags & FLG_REL_PLT) { 2266 if ((*ld_targ.t_mr.mr_perform_outreloc)(orsp, 2267 ofl) == S_ERROR) 2268 error = S_ERROR; 2269 continue; 2270 } 2271 2272 if ((orsp->rel_rtype == ld_targ.t_m.m_r_relative) || 2273 (orsp->rel_rtype == ld_targ.t_m.m_r_register)) { 2274 sorted_list[index].rl_key1 = 0; 2275 sorted_list[index].rl_key2 = 2276 /* LINTED */ 2277 (Sym_desc *)(uintptr_t)orsp->rel_rtype; 2278 } else { 2279 sorted_list[index].rl_key1 = 2280 orsp->rel_sym->sd_file->ifl_neededndx; 2281 sorted_list[index].rl_key2 = 2282 orsp->rel_sym; 2283 } 2284 2285 if (orsp->rel_flags & FLG_REL_GOT) 2286 sorted_list[index].rl_key3 = 2287 (*ld_targ.t_mr.mr_calc_got_offset)(orsp, 2288 ofl); 2289 else { 2290 if (orsp->rel_rtype == ld_targ.t_m.m_r_register) 2291 sorted_list[index].rl_key3 = 0; 2292 else { 2293 sorted_list[index].rl_key3 = 2294 orsp->rel_roffset + 2295 (Xword)_elf_getxoff(orsp-> 2296 rel_isdesc->is_indata) + 2297 orsp->rel_isdesc->is_osdesc-> 2298 os_shdr->sh_addr; 2299 } 2300 } 2301 2302 sorted_list[index++].rl_rsp = orsp; 2303 } 2304 } 2305 2306 qsort(sorted_list, (size_t)ofl->ofl_reloccnt, sizeof (Reloc_list), 2307 (int (*)(const void *, const void *))reloc_compare); 2308 2309 /* 2310 * All output relocations have now been sorted, go through 2311 * and process each relocation. 2312 */ 2313 for (index = 0; index < ofl->ofl_reloccnt; index++) { 2314 if ((*ld_targ.t_mr.mr_perform_outreloc) 2315 (sorted_list[index].rl_rsp, ofl) == S_ERROR) 2316 error = S_ERROR; 2317 } 2318 2319 return (error); 2320 } 2321 2322 /* 2323 * Process relocations. Finds every input relocation section for each output 2324 * section and invokes reloc_section() to relocate that section. 2325 */ 2326 uintptr_t 2327 ld_reloc_process(Ofl_desc *ofl) 2328 { 2329 Sg_desc *sgp; 2330 Os_desc *osp; 2331 Word ndx = 0; 2332 ofl_flag_t flags = ofl->ofl_flags; 2333 Shdr *shdr; 2334 2335 DBG_CALL(Dbg_basic_relocate(ofl->ofl_lml)); 2336 2337 /* 2338 * Determine the index of the symbol table that will be referenced by 2339 * the relocation entries. 2340 */ 2341 if (OFL_ALLOW_DYNSYM(ofl)) 2342 /* LINTED */ 2343 ndx = (Word)elf_ndxscn(ofl->ofl_osdynsym->os_scn); 2344 else if (!(flags & FLG_OF_STRIP) || (flags & FLG_OF_RELOBJ)) 2345 /* LINTED */ 2346 ndx = (Word)elf_ndxscn(ofl->ofl_ossymtab->os_scn); 2347 2348 /* 2349 * Re-initialize counters. These are used to provide relocation 2350 * offsets within the output buffers. 2351 */ 2352 ofl->ofl_relocpltsz = 0; 2353 ofl->ofl_relocgotsz = 0; 2354 ofl->ofl_relocbsssz = 0; 2355 2356 /* 2357 * Now that the output file is created and symbol update has occurred, 2358 * process the relocations collected in process_reloc(). 2359 */ 2360 if (do_sorted_outrelocs(ofl) == S_ERROR) 2361 return (S_ERROR); 2362 2363 if ((*ld_targ.t_mr.mr_do_activerelocs)(ofl) == S_ERROR) 2364 return (S_ERROR); 2365 2366 if ((flags & FLG_OF_COMREL) == 0) { 2367 Aliste idx1; 2368 2369 /* 2370 * Process the relocation sections. For each relocation 2371 * section generated for the output image update its shdr 2372 * information to reflect the symbol table it needs (sh_link) 2373 * and the section to which the relocation must be applied 2374 * (sh_info). 2375 */ 2376 for (APLIST_TRAVERSE(ofl->ofl_segs, idx1, sgp)) { 2377 Os_desc *osp; 2378 Aliste idx2; 2379 2380 for (APLIST_TRAVERSE(sgp->sg_osdescs, idx2, osp)) { 2381 if (osp->os_relosdesc == 0) 2382 continue; 2383 2384 shdr = osp->os_relosdesc->os_shdr; 2385 shdr->sh_link = ndx; 2386 /* LINTED */ 2387 shdr->sh_info = (Word)elf_ndxscn(osp->os_scn); 2388 } 2389 } 2390 2391 /* 2392 * Since the .rel[a] section is not tied to any specific 2393 * section, we'd not have found it above. 2394 */ 2395 if ((osp = ofl->ofl_osrel) != NULL) { 2396 shdr = osp->os_shdr; 2397 shdr->sh_link = ndx; 2398 shdr->sh_info = 0; 2399 } 2400 } else { 2401 /* 2402 * We only have two relocation sections here, (PLT's, 2403 * coalesced) so just hit them directly instead of stepping 2404 * over the output sections. 2405 */ 2406 if ((osp = ofl->ofl_osrelhead) != NULL) { 2407 shdr = osp->os_shdr; 2408 shdr->sh_link = ndx; 2409 shdr->sh_info = 0; 2410 } 2411 if (((osp = ofl->ofl_osplt) != NULL) && osp->os_relosdesc) { 2412 shdr = osp->os_relosdesc->os_shdr; 2413 shdr->sh_link = ndx; 2414 /* LINTED */ 2415 shdr->sh_info = (Word)elf_ndxscn(osp->os_scn); 2416 } 2417 } 2418 2419 /* 2420 * If the -z text option was given, and we have output relocations 2421 * against a non-writable, allocatable section, issue a diagnostic and 2422 * return (the actual entries that caused this error would have been 2423 * output during the relocating section phase). 2424 */ 2425 if ((flags & (FLG_OF_PURETXT | FLG_OF_TEXTREL)) == 2426 (FLG_OF_PURETXT | FLG_OF_TEXTREL)) { 2427 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_REMAIN_3)); 2428 return (S_ERROR); 2429 } 2430 2431 /* 2432 * Finally, initialize the first got entry with the address of the 2433 * .dynamic section (_DYNAMIC). 2434 */ 2435 if (flags & FLG_OF_DYNAMIC) { 2436 if ((*ld_targ.t_mr.mr_fillin_gotplt)(ofl) == S_ERROR) 2437 return (S_ERROR); 2438 } 2439 2440 /* 2441 * Now that any GOT information has been written, display the debugging 2442 * information if required. 2443 */ 2444 if ((osp = ofl->ofl_osgot) != NULL) 2445 DBG_CALL(Dbg_got_display(ofl, osp->os_shdr->sh_addr, 1, 2446 ld_targ.t_m.m_got_xnumber, ld_targ.t_m.m_got_entsize)); 2447 2448 return (1); 2449 } 2450 2451 /* 2452 * If the -z text option was given, and we have output relocations against a 2453 * non-writable, allocatable section, issue a diagnostic. Print offending 2454 * symbols in tabular form similar to the way undefined symbols are presented. 2455 * Called from reloc_count(). The actual fatal error condition is triggered on 2456 * in reloc_process() above. 2457 * 2458 * Note. For historic reasons -ztext is not a default option (however all OS 2459 * shared object builds use this option). It can be argued that this option 2460 * should also be default when generating an a.out (see 1163979). However, if 2461 * an a.out contains text relocations it is either because the user is creating 2462 * something pretty weird (they've used the -b or -znodefs options), or because 2463 * the library against which they're building wasn't constructed correctly (ie. 2464 * a function has a NOTYPE type, in which case the a.out won't generate an 2465 * associated plt). In the latter case the builder of the a.out can't do 2466 * anything to fix the error - thus we've chosen not to give the user an error, 2467 * or warning, for this case. 2468 */ 2469 static void 2470 reloc_remain_title(Ofl_desc *ofl, int warning) 2471 { 2472 const char *str1; 2473 2474 if (warning) 2475 str1 = MSG_INTL(MSG_REL_RMN_ITM_13); 2476 else 2477 str1 = MSG_INTL(MSG_REL_RMN_ITM_11); 2478 2479 eprintf(ofl->ofl_lml, ERR_NONE, MSG_INTL(MSG_REL_REMAIN_FMT_1), str1, 2480 MSG_INTL(MSG_REL_RMN_ITM_31), MSG_INTL(MSG_REL_RMN_ITM_12), 2481 MSG_INTL(MSG_REL_RMN_ITM_2), MSG_INTL(MSG_REL_RMN_ITM_32)); 2482 } 2483 2484 void 2485 ld_reloc_remain_entry(Rel_desc *orsp, Os_desc *osp, Ofl_desc *ofl) 2486 { 2487 static Boolean reloc_title = TRUE; 2488 2489 /* 2490 * -ztextoff 2491 */ 2492 if (ofl->ofl_flags1 & FLG_OF1_TEXTOFF) 2493 return; 2494 2495 /* 2496 * Only give relocation errors against loadable read-only segments. 2497 */ 2498 if ((orsp->rel_rtype == ld_targ.t_m.m_r_register) || (!osp) || 2499 (osp->os_sgdesc->sg_phdr.p_type != PT_LOAD) || 2500 (osp->os_sgdesc->sg_phdr.p_flags & PF_W)) 2501 return; 2502 2503 /* 2504 * If we are in -ztextwarn mode, it's a silent error if a relocation is 2505 * due to a 'WEAK REFERENCE'. This is because if the symbol is not 2506 * provided at run-time we will not perform a text-relocation. 2507 */ 2508 if (((ofl->ofl_flags & FLG_OF_PURETXT) == 0) && 2509 (ELF_ST_BIND(orsp->rel_sym->sd_sym->st_info) == STB_WEAK) && 2510 (orsp->rel_sym->sd_sym->st_shndx == SHN_UNDEF)) 2511 return; 2512 2513 if (reloc_title) { 2514 /* 2515 * If building with '-ztext' then emit a fatal error. If 2516 * building a executable then only emit a 'warning'. 2517 */ 2518 if (ofl->ofl_flags & FLG_OF_PURETXT) 2519 reloc_remain_title(ofl, 0); 2520 else 2521 reloc_remain_title(ofl, 1); 2522 reloc_title = FALSE; 2523 } 2524 2525 eprintf(ofl->ofl_lml, ERR_NONE, MSG_INTL(MSG_REL_REMAIN_2), 2526 demangle(orsp->rel_sname), EC_OFF(orsp->rel_roffset), 2527 orsp->rel_isdesc->is_file->ifl_name); 2528 } 2529 2530 /* 2531 * Generic encapsulation for generating a TLS got index. 2532 */ 2533 uintptr_t 2534 ld_assign_got_TLS(Boolean local, Rel_desc *rsp, Ofl_desc *ofl, Sym_desc *sdp, 2535 Gotndx *gnp, Gotref gref, Word rflag, Word ortype, Word rtype1, Word rtype2) 2536 { 2537 Word rflags; 2538 2539 if ((*ld_targ.t_mr.mr_assign_got_ndx)(&(sdp->sd_GOTndxs), gnp, 2540 gref, ofl, rsp, sdp) == S_ERROR) 2541 return (S_ERROR); 2542 2543 rflags = FLG_REL_GOT | rflag; 2544 if (local) 2545 rflags |= FLG_REL_SCNNDX; 2546 rsp->rel_rtype = rtype1; 2547 2548 if ((*ld_targ.t_mr.mr_add_outrel)(rflags, rsp, ofl) == S_ERROR) 2549 return (S_ERROR); 2550 2551 if (local && (gref == GOT_REF_TLSIE)) { 2552 /* 2553 * If this is a local LE TLS symbol, then the symbol won't be 2554 * available at runtime. The value of the local symbol will 2555 * be placed in the associated got entry, and the got 2556 * relocation is reassigned to a section symbol. 2557 */ 2558 if (ld_add_actrel(rflags, rsp, ofl) == S_ERROR) 2559 return (S_ERROR); 2560 } 2561 2562 if (rtype2) { 2563 rflags = FLG_REL_GOT | rflag; 2564 rsp->rel_rtype = rtype2; 2565 2566 if (local) { 2567 if (ld_add_actrel(rflags, rsp, ofl) == S_ERROR) 2568 return (S_ERROR); 2569 } else { 2570 if ((*ld_targ.t_mr.mr_add_outrel)(rflags, rsp, ofl) == 2571 S_ERROR) 2572 return (S_ERROR); 2573 } 2574 } 2575 2576 rsp->rel_rtype = ortype; 2577 2578 return (1); 2579 } 2580 2581 /* 2582 * Move Section related function 2583 */ 2584 static void 2585 newroffset_for_move(Sym_desc *sdp, Move *mvp, Xword offset1, Xword *offset2) 2586 { 2587 Mv_desc *mdp; 2588 Aliste idx; 2589 2590 /* 2591 * Search for matching move entry. 2592 */ 2593 for (ALIST_TRAVERSE(sdp->sd_move, idx, mdp)) { 2594 if (mdp->md_move == mvp) { 2595 /* 2596 * Update r_offset 2597 */ 2598 *offset2 = (Xword)((mdp->md_oidx - 1) * sizeof (Move) + 2599 offset1 % sizeof (Move)); 2600 return; 2601 } 2602 } 2603 } 2604 2605 void 2606 ld_adj_movereloc(Ofl_desc *ofl, Rel_desc *arsp) 2607 { 2608 Move *move = arsp->rel_move->mr_move; 2609 Sym_desc *psdp = arsp->rel_move->mr_sym; 2610 Xword newoffset; 2611 2612 if (arsp->rel_flags & FLG_REL_MOVETAB) { 2613 /* 2614 * We are relocating the move table itself. 2615 */ 2616 newroffset_for_move(psdp, move, arsp->rel_roffset, 2617 &newoffset); 2618 DBG_CALL(Dbg_move_adjmovereloc(ofl->ofl_lml, arsp->rel_roffset, 2619 newoffset, psdp->sd_name)); 2620 arsp->rel_roffset = newoffset; 2621 } else { 2622 /* 2623 * We are expanding the partial symbol. So we are generating 2624 * the relocation entry relocating the expanded partial symbol. 2625 */ 2626 arsp->rel_roffset += psdp->sd_sym->st_value - 2627 ofl->ofl_isparexpn->is_osdesc->os_shdr->sh_addr; 2628 DBG_CALL(Dbg_move_adjexpandreloc(ofl->ofl_lml, 2629 arsp->rel_roffset, psdp->sd_name)); 2630 } 2631 } 2632 2633 /* 2634 * Partially Initialized Symbol Handling routines 2635 * For RELA architecture, the second argument is reld->rel_raddend. For REL 2636 * architecure, the second argument is the value stored at the relocation 2637 * target address. 2638 */ 2639 Sym_desc * 2640 ld_am_I_partial(Rel_desc *reld, Xword val) 2641 { 2642 Ifl_desc *ifile = reld->rel_sym->sd_isc->is_file; 2643 int nlocs = ifile->ifl_locscnt, i; 2644 2645 for (i = 1; i < nlocs; i++) { 2646 Sym *osym; 2647 Sym_desc *symd = ifile->ifl_oldndx[i]; 2648 2649 if ((osym = symd->sd_osym) == 0) 2650 continue; 2651 if ((symd->sd_flags & FLG_SY_PAREXPN) == 0) 2652 continue; 2653 if ((osym->st_value <= val) && 2654 (osym->st_value + osym->st_size > val)) 2655 return (symd); 2656 } 2657 return (NULL); 2658 } 2659 2660 /* 2661 * Return True (1) if the code processing the given relocation 2662 * needs to perform byte swapping when accessing the section data. 2663 */ 2664 int 2665 ld_swap_reloc_data(Ofl_desc *ofl, Rel_desc *rsp) 2666 { 2667 /* 2668 * In a cross-link situation where the linker host and target 2669 * have opposite byte orders, it can be necessary to swap bytes 2670 * when doing relocation processing. This is indicated by the 2671 * presence of the FLG_OF1_ENCDIFF flag bit. However, swapping 2672 * is only needed for the section types that libelf doesn't 2673 * automatically xlate. 2674 */ 2675 if ((ofl->ofl_flags1 & FLG_OF1_ENCDIFF) != 0) { 2676 switch (rsp->rel_osdesc->os_shdr->sh_type) { 2677 case SHT_PROGBITS: 2678 return (1); 2679 2680 case SHT_SPARC_GOTDATA: 2681 if (ld_targ.t_m.m_mach == 2682 LD_TARG_BYCLASS(EM_SPARC, EM_SPARCV9)) 2683 return (1); 2684 break; 2685 2686 case SHT_AMD64_UNWIND: 2687 if (ld_targ.t_m.m_mach == EM_AMD64) 2688 return (1); 2689 break; 2690 } 2691 } 2692 2693 /* 2694 * If FLG_OF1_ENCDIFF isn't set, or the section isn't 2695 * progbits (or similar), then no swapping is needed. 2696 */ 2697 return (0); 2698 } 2699 2700 2701 2702 /* 2703 * Obtain the current value at the given relocation target. 2704 * 2705 * entry: 2706 * ofl - Output file descriptor 2707 * rsp - Relocation record 2708 * data - Pointer to relocation target 2709 * value - Address of variable to recieve value 2710 * 2711 * exit: 2712 * The value of the data at the relocation target has 2713 * been stored in value. 2714 */ 2715 int 2716 ld_reloc_targval_get(Ofl_desc *ofl, Rel_desc *rsp, uchar_t *data, Xword *value) 2717 { 2718 const Rel_entry *rep; 2719 2720 rep = &ld_targ.t_mr.mr_reloc_table[rsp->rel_rtype]; 2721 2722 switch (rep->re_fsize) { 2723 case 1: 2724 /* LINTED */ 2725 *value = (Xword) *((uchar_t *)data); 2726 break; 2727 case 2: 2728 { 2729 Half v; 2730 uchar_t *v_bytes = (uchar_t *)&v; 2731 2732 if (OFL_SWAP_RELOC_DATA(ofl, rsp)) { 2733 UL_ASSIGN_BSWAP_HALF(v_bytes, data); 2734 } else { 2735 UL_ASSIGN_HALF(v_bytes, data); 2736 } 2737 *value = (Xword) v; 2738 } 2739 break; 2740 case 4: 2741 { 2742 Word v; 2743 uchar_t *v_bytes = (uchar_t *)&v; 2744 2745 if (OFL_SWAP_RELOC_DATA(ofl, rsp)) { 2746 UL_ASSIGN_BSWAP_WORD(v_bytes, data); 2747 } else { 2748 UL_ASSIGN_WORD(v_bytes, data); 2749 } 2750 *value = (Xword) v; 2751 } 2752 break; 2753 default: 2754 { 2755 Conv_inv_buf_t inv_buf; 2756 eprintf(ofl->ofl_lml, ERR_FATAL, 2757 MSG_INTL(MSG_REL_UNSUPSZ), 2758 conv_reloc_type(ld_targ.t_m.m_mach, rsp->rel_rtype, 2759 0, &inv_buf), rsp->rel_isdesc->is_file->ifl_name, 2760 (rsp->rel_sname ? demangle(rsp->rel_sname) : 2761 MSG_INTL(MSG_STR_UNKNOWN)), (int)rep->re_fsize); 2762 } 2763 return (0); 2764 } 2765 return (1); 2766 } 2767 2768 2769 /* 2770 * Set the value at the given relocation target. 2771 * 2772 * entry: 2773 * ofl - Output file descriptor 2774 * rsp - Relocation record 2775 * data - Pointer to relocation target 2776 * value - Address of variable to recieve value 2777 * 2778 * exit: 2779 * The value of the data at the relocation target has 2780 * been stored in value. 2781 */ 2782 int 2783 ld_reloc_targval_set(Ofl_desc *ofl, Rel_desc *rsp, uchar_t *data, Xword value) 2784 { 2785 const Rel_entry *rep; 2786 2787 rep = &ld_targ.t_mr.mr_reloc_table[rsp->rel_rtype]; 2788 2789 switch (rep->re_fsize) { 2790 case 1: 2791 /* LINTED */ 2792 *((uchar_t *)data) = (uchar_t)value; 2793 break; 2794 case 2: 2795 { 2796 Half v = (Half)value; 2797 uchar_t *v_bytes = (uchar_t *)&v; 2798 2799 if (OFL_SWAP_RELOC_DATA(ofl, rsp)) { 2800 UL_ASSIGN_BSWAP_HALF(data, v_bytes); 2801 } else { 2802 UL_ASSIGN_HALF(data, v_bytes); 2803 } 2804 } 2805 break; 2806 case 4: 2807 { 2808 Word v = (Word)value; 2809 uchar_t *v_bytes = (uchar_t *)&v; 2810 2811 if (OFL_SWAP_RELOC_DATA(ofl, rsp)) { 2812 UL_ASSIGN_BSWAP_WORD(data, v_bytes); 2813 } else { 2814 UL_ASSIGN_WORD(data, v_bytes); 2815 } 2816 } 2817 break; 2818 default: 2819 { 2820 Conv_inv_buf_t inv_buf; 2821 eprintf(ofl->ofl_lml, ERR_FATAL, 2822 MSG_INTL(MSG_REL_UNSUPSZ), 2823 conv_reloc_type(ld_targ.t_m.m_mach, rsp->rel_rtype, 2824 0, &inv_buf), rsp->rel_isdesc->is_file->ifl_name, 2825 (rsp->rel_sname ? demangle(rsp->rel_sname) : 2826 MSG_INTL(MSG_STR_UNKNOWN)), (int)rep->re_fsize); 2827 } 2828 return (0); 2829 } 2830 return (1); 2831 } 2832 2833 2834 /* 2835 * Because of the combinations of 32-bit lib providing 64-bit support, and 2836 * visa-versa, the use of krtld's dorelocs can result in differing message 2837 * requirements that make msg.c/msg.h creation and chkmsg "interesting". 2838 * Thus the actual message files contain a couple of entries to satisfy 2839 * each architectures build. Here we add dummy calls to quieten chkmsg. 2840 * 2841 * chkmsg: MSG_INTL(MSG_REL_NOFIT) 2842 * chkmsg: MSG_INTL(MSG_REL_NONALIGN) 2843 */ 2844