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) 1990, 1991 UNIX System Laboratories, Inc. 24 * Copyright (c) 1988 AT&T 25 * All Rights Reserved 26 * 27 * Copyright (c) 1992, 2010, Oracle and/or its affiliates. All rights reserved. 28 */ 29 30 /* Get the x86 version of the relocation engine */ 31 #define DO_RELOC_LIBLD_X86 32 33 #include <string.h> 34 #include <stdio.h> 35 #include <sys/elf_386.h> 36 #include <debug.h> 37 #include <reloc.h> 38 #include <i386/machdep_x86.h> 39 #include "msg.h" 40 #include "_libld.h" 41 42 /* 43 * Search the GOT index list for a GOT entry with a matching reference. 44 */ 45 /* ARGSUSED3 */ 46 static Gotndx * 47 ld_find_got_ndx(Alist *alp, Gotref gref, Ofl_desc *ofl, Rel_desc *rdesc) 48 { 49 Aliste idx; 50 Gotndx *gnp; 51 52 if ((gref == GOT_REF_TLSLD) && ofl->ofl_tlsldgotndx) 53 return (ofl->ofl_tlsldgotndx); 54 55 for (ALIST_TRAVERSE(alp, idx, gnp)) { 56 if (gnp->gn_gotref == gref) 57 return (gnp); 58 } 59 return (NULL); 60 } 61 62 static Xword 63 ld_calc_got_offset(Rel_desc *rdesc, Ofl_desc *ofl) 64 { 65 Os_desc *osp = ofl->ofl_osgot; 66 Sym_desc *sdp = rdesc->rel_sym; 67 Xword gotndx; 68 Gotref gref; 69 Gotndx *gnp; 70 71 if (rdesc->rel_flags & FLG_REL_DTLS) 72 gref = GOT_REF_TLSGD; 73 else if (rdesc->rel_flags & FLG_REL_MTLS) 74 gref = GOT_REF_TLSLD; 75 else if (rdesc->rel_flags & FLG_REL_STLS) 76 gref = GOT_REF_TLSIE; 77 else 78 gref = GOT_REF_GENERIC; 79 80 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, NULL); 81 assert(gnp); 82 83 gotndx = (Xword)gnp->gn_gotndx; 84 85 if ((rdesc->rel_flags & FLG_REL_DTLS) && 86 (rdesc->rel_rtype == R_386_TLS_DTPOFF32)) 87 gotndx++; 88 89 return ((Xword)(osp->os_shdr->sh_addr + (gotndx * M_GOT_ENTSIZE))); 90 } 91 92 static Word 93 ld_init_rel(Rel_desc *reld, Word *typedata, void *reloc) 94 { 95 Rel *rel = (Rel *)reloc; 96 97 /* LINTED */ 98 reld->rel_rtype = (Word)ELF_R_TYPE(rel->r_info, M_MACH); 99 reld->rel_roffset = rel->r_offset; 100 reld->rel_raddend = 0; 101 *typedata = 0; 102 103 return ((Word)ELF_R_SYM(rel->r_info)); 104 } 105 106 static void 107 ld_mach_eflags(Ehdr *ehdr, Ofl_desc *ofl) 108 { 109 ofl->ofl_dehdr->e_flags |= ehdr->e_flags; 110 } 111 112 static void 113 ld_mach_make_dynamic(Ofl_desc *ofl, size_t *cnt) 114 { 115 if (!(ofl->ofl_flags & FLG_OF_RELOBJ)) { 116 /* 117 * Create this entry if we are going to create a PLT table. 118 */ 119 if (ofl->ofl_pltcnt) 120 (*cnt)++; /* DT_PLTGOT */ 121 } 122 } 123 124 static void 125 ld_mach_update_odynamic(Ofl_desc *ofl, Dyn **dyn) 126 { 127 if (((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) && ofl->ofl_pltcnt) { 128 (*dyn)->d_tag = DT_PLTGOT; 129 if (ofl->ofl_osgot) 130 (*dyn)->d_un.d_ptr = ofl->ofl_osgot->os_shdr->sh_addr; 131 else 132 (*dyn)->d_un.d_ptr = 0; 133 (*dyn)++; 134 } 135 } 136 137 static Xword 138 ld_calc_plt_addr(Sym_desc *sdp, Ofl_desc *ofl) 139 { 140 Xword value; 141 142 value = (Xword)(ofl->ofl_osplt->os_shdr->sh_addr) + 143 M_PLT_RESERVSZ + ((sdp->sd_aux->sa_PLTndx - 1) * M_PLT_ENTSIZE); 144 return (value); 145 } 146 147 /* 148 * Build a single plt entry - code is: 149 * if (building a.out) 150 * JMP *got_off 151 * else 152 * JMP *got_off@GOT(%ebx) 153 * PUSHL &rel_off 154 * JMP -n(%pc) # -n is pcrel offset to first plt entry 155 * 156 * The got_off@GOT entry gets filled with the address of the PUSHL, 157 * so the first pass through the plt jumps back here, jumping 158 * in turn to the first plt entry, which jumps to the dynamic 159 * linker. The dynamic linker then patches the GOT, rerouting 160 * future plt calls to the proper destination. 161 */ 162 static void 163 plt_entry(Ofl_desc * ofl, Word rel_off, Sym_desc * sdp) 164 { 165 uchar_t *pltent, *gotent; 166 Sword plt_off; 167 Word got_off; 168 int bswap = (ofl->ofl_flags1 & FLG_OF1_ENCDIFF) != 0; 169 170 got_off = sdp->sd_aux->sa_PLTGOTndx * M_GOT_ENTSIZE; 171 plt_off = M_PLT_RESERVSZ + ((sdp->sd_aux->sa_PLTndx - 1) * 172 M_PLT_ENTSIZE); 173 pltent = (uchar_t *)(ofl->ofl_osplt->os_outdata->d_buf) + plt_off; 174 gotent = (uchar_t *)(ofl->ofl_osgot->os_outdata->d_buf) + got_off; 175 176 /* 177 * Fill in the got entry with the address of the next instruction. 178 */ 179 /* LINTED */ 180 *(Word *)gotent = ofl->ofl_osplt->os_shdr->sh_addr + plt_off + 181 M_PLT_INSSIZE; 182 if (bswap) 183 /* LINTED */ 184 *(Word *)gotent = ld_bswap_Word(*(Word *)gotent); 185 186 if (!(ofl->ofl_flags & FLG_OF_SHAROBJ)) { 187 pltent[0] = M_SPECIAL_INST; 188 pltent[1] = M_JMP_DISP_IND; 189 pltent += 2; 190 /* LINTED */ 191 *(Word *)pltent = (Word)(ofl->ofl_osgot->os_shdr->sh_addr + 192 got_off); 193 } else { 194 pltent[0] = M_SPECIAL_INST; 195 pltent[1] = M_JMP_REG_DISP_IND; 196 pltent += 2; 197 /* LINTED */ 198 *(Word *)pltent = (Word)got_off; 199 } 200 if (bswap) 201 /* LINTED */ 202 *(Word *)pltent = ld_bswap_Word(*(Word *)pltent); 203 pltent += 4; 204 205 pltent[0] = M_INST_PUSHL; 206 pltent++; 207 /* LINTED */ 208 *(Word *)pltent = (Word)rel_off; 209 if (bswap) 210 /* LINTED */ 211 *(Word *)pltent = ld_bswap_Word(*(Word *)pltent); 212 pltent += 4; 213 214 plt_off = -(plt_off + 16); /* JMP, PUSHL, JMP take 16 bytes */ 215 pltent[0] = M_INST_JMP; 216 pltent++; 217 /* LINTED */ 218 *(Word *)pltent = (Word)plt_off; 219 if (bswap) 220 /* LINTED */ 221 *(Word *)pltent = ld_bswap_Word(*(Word *)pltent); 222 } 223 224 static uintptr_t 225 ld_perform_outreloc(Rel_desc * orsp, Ofl_desc * ofl, Boolean *remain_seen) 226 { 227 Os_desc * relosp, * osp = 0; 228 Word ndx, roffset, value; 229 Rel rea; 230 char *relbits; 231 Sym_desc * sdp, * psym = (Sym_desc *)0; 232 int sectmoved = 0; 233 234 sdp = orsp->rel_sym; 235 236 /* 237 * If the section this relocation is against has been discarded 238 * (-zignore), then also discard (skip) the relocation itself. 239 */ 240 if (orsp->rel_isdesc && ((orsp->rel_flags & 241 (FLG_REL_GOT | FLG_REL_BSS | FLG_REL_PLT | FLG_REL_NOINFO)) == 0) && 242 (orsp->rel_isdesc->is_flags & FLG_IS_DISCARD)) { 243 DBG_CALL(Dbg_reloc_discard(ofl->ofl_lml, M_MACH, orsp)); 244 return (1); 245 } 246 247 /* 248 * If this is a relocation against a move table, or expanded move 249 * table, adjust the relocation entries. 250 */ 251 if (RELAUX_GET_MOVE(orsp)) 252 ld_adj_movereloc(ofl, orsp); 253 254 /* 255 * If this is a relocation against a section using a partial initialized 256 * symbol, adjust the embedded symbol info. 257 * 258 * The second argument of the am_I_partial() is the value stored at the 259 * target address relocation is going to be applied. 260 */ 261 if (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) { 262 if (ofl->ofl_parsyms && 263 (sdp->sd_isc->is_flags & FLG_IS_RELUPD) && 264 /* LINTED */ 265 (psym = ld_am_I_partial(orsp, *(Xword *) 266 ((uchar_t *)(orsp->rel_isdesc->is_indata->d_buf) + 267 orsp->rel_roffset)))) { 268 DBG_CALL(Dbg_move_outsctadj(ofl->ofl_lml, psym)); 269 sectmoved = 1; 270 } 271 } 272 273 value = sdp->sd_sym->st_value; 274 275 if (orsp->rel_flags & FLG_REL_GOT) { 276 osp = ofl->ofl_osgot; 277 roffset = (Word)ld_calc_got_offset(orsp, ofl); 278 279 } else if (orsp->rel_flags & FLG_REL_PLT) { 280 /* 281 * Note that relocations for PLT's actually 282 * cause a relocation againt the GOT. 283 */ 284 osp = ofl->ofl_osplt; 285 roffset = (Word) (ofl->ofl_osgot->os_shdr->sh_addr) + 286 sdp->sd_aux->sa_PLTGOTndx * M_GOT_ENTSIZE; 287 288 plt_entry(ofl, osp->os_relosdesc->os_szoutrels, sdp); 289 290 } else if (orsp->rel_flags & FLG_REL_BSS) { 291 /* 292 * This must be a R_386_COPY. For these set the roffset to 293 * point to the new symbols location. 294 */ 295 osp = ofl->ofl_isbss->is_osdesc; 296 roffset = (Word)value; 297 } else { 298 osp = RELAUX_GET_OSDESC(orsp); 299 300 /* 301 * Calculate virtual offset of reference point; equals offset 302 * into section + vaddr of section for loadable sections, or 303 * offset plus section displacement for nonloadable sections. 304 */ 305 roffset = orsp->rel_roffset + 306 (Off)_elf_getxoff(orsp->rel_isdesc->is_indata); 307 if (!(ofl->ofl_flags & FLG_OF_RELOBJ)) 308 roffset += orsp->rel_isdesc->is_osdesc-> 309 os_shdr->sh_addr; 310 } 311 312 if ((osp == 0) || ((relosp = osp->os_relosdesc) == 0)) 313 relosp = ofl->ofl_osrel; 314 315 /* 316 * Assign the symbols index for the output relocation. If the 317 * relocation refers to a SECTION symbol then it's index is based upon 318 * the output sections symbols index. Otherwise the index can be 319 * derived from the symbols index itself. 320 */ 321 if (orsp->rel_rtype == R_386_RELATIVE) 322 ndx = STN_UNDEF; 323 else if ((orsp->rel_flags & FLG_REL_SCNNDX) || 324 (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION)) { 325 if (sectmoved == 0) { 326 /* 327 * Check for a null input section. This can 328 * occur if this relocation references a symbol 329 * generated by sym_add_sym(). 330 */ 331 if (sdp->sd_isc && sdp->sd_isc->is_osdesc) 332 ndx = sdp->sd_isc->is_osdesc->os_identndx; 333 else 334 ndx = sdp->sd_shndx; 335 } else 336 ndx = ofl->ofl_parexpnndx; 337 } else 338 ndx = sdp->sd_symndx; 339 340 /* 341 * If we have a replacement value for the relocation 342 * target, put it in place now. 343 */ 344 if (orsp->rel_flags & FLG_REL_NADDEND) { 345 Xword addend = orsp->rel_raddend; 346 uchar_t *addr; 347 348 /* 349 * Get the address of the data item we need to modify. 350 */ 351 addr = (uchar_t *)((uintptr_t)orsp->rel_roffset + 352 (uintptr_t)_elf_getxoff(orsp->rel_isdesc->is_indata)); 353 addr += (uintptr_t)RELAUX_GET_OSDESC(orsp)->os_outdata->d_buf; 354 if (ld_reloc_targval_set(ofl, orsp, addr, addend) == 0) 355 return (S_ERROR); 356 } 357 358 if ((orsp->rel_rtype != M_R_NONE) && 359 (orsp->rel_rtype != M_R_RELATIVE)) { 360 if (ndx == 0) { 361 Conv_inv_buf_t inv_buf; 362 Is_desc *isp = orsp->rel_isdesc; 363 364 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_REL_NOSYMBOL), 365 conv_reloc_type(ofl->ofl_nehdr->e_machine, 366 orsp->rel_rtype, 0, &inv_buf), 367 isp->is_file->ifl_name, EC_WORD(isp->is_scnndx), 368 isp->is_name, EC_XWORD(roffset)); 369 return (S_ERROR); 370 } 371 } 372 373 rea.r_info = ELF_R_INFO(ndx, orsp->rel_rtype); 374 rea.r_offset = roffset; 375 DBG_CALL(Dbg_reloc_out(ofl, ELF_DBG_LD, SHT_REL, &rea, relosp->os_name, 376 ld_reloc_sym_name(orsp))); 377 378 /* 379 * Assert we haven't walked off the end of our relocation table. 380 */ 381 assert(relosp->os_szoutrels <= relosp->os_shdr->sh_size); 382 383 relbits = (char *)relosp->os_outdata->d_buf; 384 385 (void) memcpy((relbits + relosp->os_szoutrels), 386 (char *)&rea, sizeof (Rel)); 387 relosp->os_szoutrels += sizeof (Rel); 388 389 /* 390 * Determine if this relocation is against a non-writable, allocatable 391 * section. If so we may need to provide a text relocation diagnostic. 392 * Note that relocations against the .plt (R_386_JMP_SLOT) actually 393 * result in modifications to the .got. 394 */ 395 if (orsp->rel_rtype == R_386_JMP_SLOT) 396 osp = ofl->ofl_osgot; 397 398 ld_reloc_remain_entry(orsp, osp, ofl, remain_seen); 399 return (1); 400 } 401 402 /* 403 * i386 Instructions for TLS processing 404 */ 405 static uchar_t tlsinstr_gd_ie[] = { 406 /* 407 * 0x00 movl %gs:0x0, %eax 408 */ 409 0x65, 0xa1, 0x00, 0x00, 0x00, 0x00, 410 /* 411 * 0x06 addl x(%eax), %eax 412 * 0x0c ... 413 */ 414 0x03, 0x80, 0x00, 0x00, 0x00, 0x00 415 }; 416 417 static uchar_t tlsinstr_gd_le[] = { 418 /* 419 * 0x00 movl %gs:0x0, %eax 420 */ 421 0x65, 0xa1, 0x00, 0x00, 0x00, 0x00, 422 /* 423 * 0x06 addl $0x0, %eax 424 */ 425 0x05, 0x00, 0x00, 0x00, 0x00, 426 /* 427 * 0x0b nop 428 * 0x0c 429 */ 430 0x90 431 }; 432 433 static uchar_t tlsinstr_ld_le_movgs[] = { 434 /* 435 * 0x00 movl %gs:0x0,%eax 436 */ 437 0x65, 0xa1, 0x00, 0x00, 0x00, 0x00, 438 }; 439 440 /* 441 * 0x00 nopl 0(%eax,%eax) -- the intel recommended 5-byte nop 442 * See Intel® 64 and IA-32 Architectures Software Developer’s Manual 443 * Volume 2B: Instruction Set Reference, M-U 444 * Table 4-12, Recommended Multi-Byte Sequence of NOP Instruction 445 */ 446 static uchar_t tlsinstr_nop5[] = { 447 448 0x0f, 0x1f, 0x44, 0x00, 0x00 449 }; 450 451 #define TLS_GD_IE_MOV 0x8b /* movl opcode */ 452 #define TLS_GD_IE_POP 0x58 /* popl + reg */ 453 454 #define TLS_GD_LE_MOVL 0xb8 /* movl + reg */ 455 456 #define TLS_NOP 0x90 /* NOP instruction */ 457 458 #define MODRM_MSK_MOD 0xc0 459 #define MODRM_MSK_RO 0x38 460 #define MODRM_MSK_RM 0x07 461 462 #define SIB_MSK_SS 0xc0 463 #define SIB_MSK_IND 0x38 464 #define SIB_MSK_BS 0x07 465 466 static Fixupret 467 tls_fixups(Ofl_desc *ofl, Rel_desc *arsp) 468 { 469 Sym_desc *sdp = arsp->rel_sym; 470 Word rtype = arsp->rel_rtype; 471 uchar_t *offset, r1, r2; 472 473 offset = (uchar_t *)((uintptr_t)arsp->rel_roffset + 474 (uintptr_t)_elf_getxoff(arsp->rel_isdesc->is_indata) + 475 (uintptr_t)RELAUX_GET_OSDESC(arsp)->os_outdata->d_buf); 476 477 if (sdp->sd_ref == REF_DYN_NEED) { 478 /* 479 * IE reference model 480 */ 481 switch (rtype) { 482 case R_386_TLS_GD: 483 /* 484 * Transition: 485 * 0x0 leal x@tlsgd(,r1,1), %eax 486 * 0x7 call ___tls_get_addr 487 * 0xc 488 * To: 489 * 0x0 movl %gs:0, %eax 490 * 0x6 addl x@gotntpoff(r1), %eax 491 */ 492 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 493 R_386_TLS_GOTIE, arsp, ld_reloc_sym_name)); 494 arsp->rel_rtype = R_386_TLS_GOTIE; 495 arsp->rel_roffset += 5; 496 497 /* 498 * Adjust 'offset' to beginning of instruction 499 * sequence. 500 */ 501 offset -= 3; 502 r1 = (offset[2] & SIB_MSK_IND) >> 3; 503 (void) memcpy(offset, tlsinstr_gd_ie, 504 sizeof (tlsinstr_gd_ie)); 505 506 /* 507 * set register %r1 into the addl 508 * instruction. 509 */ 510 offset[0x7] |= r1; 511 return (FIX_RELOC); 512 513 case R_386_TLS_GD_PLT: 514 /* 515 * Fixup done via the TLS_GD relocation 516 */ 517 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 518 R_386_NONE, arsp, ld_reloc_sym_name)); 519 return (FIX_DONE); 520 } 521 } 522 523 /* 524 * LE reference model 525 */ 526 switch (rtype) { 527 case R_386_TLS_GD: 528 /* 529 * Transition: 530 * 0x0 leal x@tlsgd(,r1,1), %eax 531 * 0x7 call ___tls_get_addr 532 * 0xc 533 * To: 534 * 0x0 movl %gs:0, %eax 535 * 0x6 addl $x@ntpoff, %eax 536 * 0xb nop 537 * 0xc 538 */ 539 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 540 R_386_TLS_LE, arsp, ld_reloc_sym_name)); 541 542 arsp->rel_rtype = R_386_TLS_LE; 543 arsp->rel_roffset += 4; 544 545 /* 546 * Adjust 'offset' to beginning of instruction 547 * sequence. 548 */ 549 offset -= 3; 550 (void) memcpy(offset, tlsinstr_gd_le, 551 sizeof (tlsinstr_gd_le)); 552 return (FIX_RELOC); 553 554 case R_386_TLS_GD_PLT: 555 case R_386_PLT32: 556 /* 557 * Fixup done via the TLS_GD/TLS_LDM relocation processing 558 * and ld_reloc_plt() handling __tls_get_addr(). 559 */ 560 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 561 R_386_NONE, arsp, ld_reloc_sym_name)); 562 return (FIX_DONE); 563 564 case R_386_TLS_LDM_PLT: 565 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 566 R_386_NONE, arsp, ld_reloc_sym_name)); 567 568 /* 569 * Transition: 570 * call __tls_get_addr() 571 * to: 572 * nopl 0x0(%eax,%eax) 573 */ 574 (void) memcpy(offset - 1, tlsinstr_nop5, 575 sizeof (tlsinstr_nop5)); 576 return (FIX_DONE); 577 578 case R_386_TLS_LDM: 579 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 580 R_386_NONE, arsp, ld_reloc_sym_name)); 581 582 /* 583 * Transition: 584 * 585 * 0x00 leal x1@tlsldm(%ebx), %eax 586 * 0x06 call ___tls_get_addr 587 * 588 * to: 589 * 590 * 0x00 movl %gs:0, %eax 591 */ 592 (void) memcpy(offset - 2, tlsinstr_ld_le_movgs, 593 sizeof (tlsinstr_ld_le_movgs)); 594 595 /* 596 * We implicitly treat this as if a R_386_TLS_LDM_PLT for the 597 * __tls_get_addr call followed it as the GNU compiler 598 * doesn't generate one. This is safe, because if one _does_ 599 * exist we'll just write the nop again. 600 */ 601 (void) memcpy(offset + 4, tlsinstr_nop5, 602 sizeof (tlsinstr_nop5)); 603 return (FIX_DONE); 604 605 case R_386_TLS_LDO_32: 606 /* 607 * Instructions: 608 * 609 * 0x10 leal x1@dtpoff(%eax), %edx R_386_TLS_LDO_32 610 * to 611 * 0x10 leal x1@ntpoff(%eax), %edx R_386_TLS_LE 612 * 613 */ 614 offset -= 2; 615 616 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 617 R_386_TLS_LE, arsp, ld_reloc_sym_name)); 618 arsp->rel_rtype = R_386_TLS_LE; 619 return (FIX_RELOC); 620 621 case R_386_TLS_GOTIE: 622 /* 623 * These transitions are a little different than the 624 * others, in that we could have multiple instructions 625 * pointed to by a single relocation. Depending upon the 626 * instruction, we perform a different code transition. 627 * 628 * Here's the known transitions: 629 * 630 * 1) movl foo@gotntpoff(%reg1), %reg2 631 * 0x8b, 0x80 | (reg2 << 3) | reg1, foo@gotntpoff 632 * 633 * 2) addl foo@gotntpoff(%reg1), %reg2 634 * 0x03, 0x80 | (reg2 << 3) | reg1, foo@gotntpoff 635 * 636 * Transitions IE -> LE 637 * 638 * 1) movl $foo@ntpoff, %reg2 639 * 0xc7, 0xc0 | reg2, foo@ntpoff 640 * 641 * 2) addl $foo@ntpoff, %reg2 642 * 0x81, 0xc0 | reg2, foo@ntpoff 643 * 644 * Note: reg1 != 4 (%esp) 645 */ 646 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 647 R_386_TLS_LE, arsp, ld_reloc_sym_name)); 648 arsp->rel_rtype = R_386_TLS_LE; 649 650 offset -= 2; 651 r2 = (offset[1] & MODRM_MSK_RO) >> 3; 652 if (offset[0] == 0x8b) { 653 /* case 1 above */ 654 offset[0] = 0xc7; /* movl */ 655 offset[1] = 0xc0 | r2; 656 return (FIX_RELOC); 657 } 658 659 if (offset[0] == 0x03) { 660 /* case 2 above */ 661 assert(offset[0] == 0x03); 662 offset[0] = 0x81; /* addl */ 663 offset[1] = 0xc0 | r2; 664 return (FIX_RELOC); 665 } 666 667 /* 668 * Unexpected instruction sequence - fatal error. 669 */ 670 { 671 Conv_inv_buf_t inv_buf; 672 673 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_REL_BADTLSINS), 674 conv_reloc_386_type(arsp->rel_rtype, 0, &inv_buf), 675 arsp->rel_isdesc->is_file->ifl_name, 676 ld_reloc_sym_name(arsp), 677 arsp->rel_isdesc->is_name, 678 EC_OFF(arsp->rel_roffset)); 679 } 680 return (FIX_ERROR); 681 682 case R_386_TLS_IE: 683 /* 684 * These transitions are a little different than the 685 * others, in that we could have multiple instructions 686 * pointed to by a single relocation. Depending upon the 687 * instruction, we perform a different code transition. 688 * 689 * Here's the known transitions: 690 * 1) movl foo@indntpoff, %eax 691 * 0xa1, foo@indntpoff 692 * 693 * 2) movl foo@indntpoff, %eax 694 * 0x8b, 0x05 | (reg << 3), foo@gotntpoff 695 * 696 * 3) addl foo@indntpoff, %eax 697 * 0x03, 0x05 | (reg << 3), foo@gotntpoff 698 * 699 * Transitions IE -> LE 700 * 701 * 1) movl $foo@ntpoff, %eax 702 * 0xb8, foo@ntpoff 703 * 704 * 2) movl $foo@ntpoff, %reg 705 * 0xc7, 0xc0 | reg, foo@ntpoff 706 * 707 * 3) addl $foo@ntpoff, %reg 708 * 0x81, 0xc0 | reg, foo@ntpoff 709 */ 710 arsp->rel_rtype = R_386_TLS_LE; 711 offset--; 712 if (offset[0] == 0xa1) { 713 /* case 1 above */ 714 offset[0] = 0xb8; /* movl */ 715 return (FIX_RELOC); 716 } 717 718 offset--; 719 if (offset[0] == 0x8b) { 720 /* case 2 above */ 721 r2 = (offset[1] & MODRM_MSK_RO) >> 3; 722 offset[0] = 0xc7; /* movl */ 723 offset[1] = 0xc0 | r2; 724 return (FIX_RELOC); 725 } 726 if (offset[0] == 0x03) { 727 /* case 3 above */ 728 r2 = (offset[1] & MODRM_MSK_RO) >> 3; 729 offset[0] = 0x81; /* addl */ 730 offset[1] = 0xc0 | r2; 731 return (FIX_RELOC); 732 } 733 /* 734 * Unexpected instruction sequence - fatal error. 735 */ 736 { 737 Conv_inv_buf_t inv_buf; 738 739 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_REL_BADTLSINS), 740 conv_reloc_386_type(arsp->rel_rtype, 0, &inv_buf), 741 arsp->rel_isdesc->is_file->ifl_name, 742 ld_reloc_sym_name(arsp), 743 arsp->rel_isdesc->is_name, 744 EC_OFF(arsp->rel_roffset)); 745 } 746 return (FIX_ERROR); 747 } 748 return (FIX_RELOC); 749 } 750 751 static uintptr_t 752 ld_do_activerelocs(Ofl_desc *ofl) 753 { 754 Rel_desc *arsp; 755 Rel_cachebuf *rcbp; 756 Aliste idx; 757 uintptr_t return_code = 1; 758 ofl_flag_t flags = ofl->ofl_flags; 759 760 if (aplist_nitems(ofl->ofl_actrels.rc_list) != 0) 761 DBG_CALL(Dbg_reloc_doact_title(ofl->ofl_lml)); 762 763 /* 764 * Process active relocations. 765 */ 766 REL_CACHE_TRAVERSE(&ofl->ofl_actrels, idx, rcbp, arsp) { 767 uchar_t *addr; 768 Xword value; 769 Sym_desc *sdp; 770 const char *ifl_name; 771 Xword refaddr; 772 int moved = 0; 773 Gotref gref; 774 Os_desc *osp; 775 776 /* 777 * If the section this relocation is against has been discarded 778 * (-zignore), then discard (skip) the relocation itself. 779 */ 780 if ((arsp->rel_isdesc->is_flags & FLG_IS_DISCARD) && 781 ((arsp->rel_flags & (FLG_REL_GOT | FLG_REL_BSS | 782 FLG_REL_PLT | FLG_REL_NOINFO)) == 0)) { 783 DBG_CALL(Dbg_reloc_discard(ofl->ofl_lml, M_MACH, arsp)); 784 continue; 785 } 786 787 /* 788 * We determine what the 'got reference' model (if required) 789 * is at this point. This needs to be done before tls_fixup() 790 * since it may 'transition' our instructions. 791 * 792 * The got table entries have already been assigned, 793 * and we bind to those initial entries. 794 */ 795 if (arsp->rel_flags & FLG_REL_DTLS) 796 gref = GOT_REF_TLSGD; 797 else if (arsp->rel_flags & FLG_REL_MTLS) 798 gref = GOT_REF_TLSLD; 799 else if (arsp->rel_flags & FLG_REL_STLS) 800 gref = GOT_REF_TLSIE; 801 else 802 gref = GOT_REF_GENERIC; 803 804 /* 805 * Perform any required TLS fixups. 806 */ 807 if (arsp->rel_flags & FLG_REL_TLSFIX) { 808 Fixupret ret; 809 810 if ((ret = tls_fixups(ofl, arsp)) == FIX_ERROR) 811 return (S_ERROR); 812 if (ret == FIX_DONE) 813 continue; 814 } 815 816 /* 817 * If this is a relocation against a move table, or 818 * expanded move table, adjust the relocation entries. 819 */ 820 if (RELAUX_GET_MOVE(arsp)) 821 ld_adj_movereloc(ofl, arsp); 822 823 sdp = arsp->rel_sym; 824 refaddr = arsp->rel_roffset + 825 (Off)_elf_getxoff(arsp->rel_isdesc->is_indata); 826 827 if (arsp->rel_flags & FLG_REL_CLVAL) 828 value = 0; 829 else if (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) { 830 /* 831 * The value for a symbol pointing to a SECTION 832 * is based off of that sections position. 833 */ 834 if (sdp->sd_isc->is_flags & FLG_IS_RELUPD) { 835 Sym_desc *sym; 836 Xword radd; 837 uchar_t *raddr = (uchar_t *) 838 arsp->rel_isdesc->is_indata->d_buf + 839 arsp->rel_roffset; 840 841 /* 842 * This is a REL platform. Hence, the second 843 * argument of ld_am_I_partial() is the value 844 * stored at the target address where the 845 * relocation is going to be applied. 846 */ 847 if (ld_reloc_targval_get(ofl, arsp, raddr, 848 &radd) == 0) 849 return (S_ERROR); 850 sym = ld_am_I_partial(arsp, radd); 851 if (sym) { 852 Sym *osym = sym->sd_osym; 853 854 /* 855 * The symbol was moved, so adjust the 856 * value relative to the new section. 857 */ 858 value = sym->sd_sym->st_value; 859 moved = 1; 860 861 /* 862 * The original raddend covers the 863 * displacement from the section start 864 * to the desired address. The value 865 * computed above gets us from the 866 * section start to the start of the 867 * symbol range. Adjust the old raddend 868 * to remove the offset from section 869 * start to symbol start, leaving the 870 * displacement within the range of 871 * the symbol. 872 */ 873 if (osym->st_value != 0) { 874 radd -= osym->st_value; 875 if (ld_reloc_targval_set(ofl, 876 arsp, raddr, radd) == 0) 877 return (S_ERROR); 878 } 879 } 880 } 881 if (!moved) { 882 value = _elf_getxoff(sdp->sd_isc->is_indata); 883 if (sdp->sd_isc->is_shdr->sh_flags & SHF_ALLOC) 884 value += sdp->sd_isc-> 885 is_osdesc->os_shdr->sh_addr; 886 } 887 if (sdp->sd_isc->is_shdr->sh_flags & SHF_TLS) 888 value -= ofl->ofl_tlsphdr->p_vaddr; 889 890 } else if (IS_SIZE(arsp->rel_rtype)) { 891 /* 892 * Size relocations require the symbols size. 893 */ 894 value = sdp->sd_sym->st_size; 895 896 } else if ((sdp->sd_flags & FLG_SY_CAP) && 897 sdp->sd_aux && sdp->sd_aux->sa_PLTndx) { 898 /* 899 * If relocation is against a capabilities symbol, we 900 * need to jump to an associated PLT, so that at runtime 901 * ld.so.1 is involved to determine the best binding 902 * choice. Otherwise, the value is the symbols value. 903 */ 904 value = ld_calc_plt_addr(sdp, ofl); 905 906 } else 907 value = sdp->sd_sym->st_value; 908 909 /* 910 * Relocation against the GLOBAL_OFFSET_TABLE. 911 */ 912 if ((arsp->rel_flags & FLG_REL_GOT) && 913 !ld_reloc_set_aux_osdesc(ofl, arsp, ofl->ofl_osgot)) 914 return (S_ERROR); 915 osp = RELAUX_GET_OSDESC(arsp); 916 917 /* 918 * If loadable and not producing a relocatable object add the 919 * sections virtual address to the reference address. 920 */ 921 if ((arsp->rel_flags & FLG_REL_LOAD) && 922 ((flags & FLG_OF_RELOBJ) == 0)) 923 refaddr += 924 arsp->rel_isdesc->is_osdesc->os_shdr->sh_addr; 925 926 /* 927 * If this entry has a PLT assigned to it, its value is actually 928 * the address of the PLT (and not the address of the function). 929 */ 930 if (IS_PLT(arsp->rel_rtype)) { 931 if (sdp->sd_aux && sdp->sd_aux->sa_PLTndx) 932 value = ld_calc_plt_addr(sdp, ofl); 933 } 934 935 /* 936 * Determine whether the value needs further adjustment. Filter 937 * through the attributes of the relocation to determine what 938 * adjustment is required. Note, many of the following cases 939 * are only applicable when a .got is present. As a .got is 940 * not generated when a relocatable object is being built, 941 * any adjustments that require a .got need to be skipped. 942 */ 943 if ((arsp->rel_flags & FLG_REL_GOT) && 944 ((flags & FLG_OF_RELOBJ) == 0)) { 945 Xword R1addr; 946 uintptr_t R2addr; 947 Word gotndx; 948 Gotndx *gnp; 949 950 /* 951 * Perform relocation against GOT table. Since this 952 * doesn't fit exactly into a relocation we place the 953 * appropriate byte in the GOT directly 954 * 955 * Calculate offset into GOT at which to apply 956 * the relocation. 957 */ 958 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, NULL); 959 assert(gnp); 960 961 if (arsp->rel_rtype == R_386_TLS_DTPOFF32) 962 gotndx = gnp->gn_gotndx + 1; 963 else 964 gotndx = gnp->gn_gotndx; 965 966 R1addr = (Xword)(gotndx * M_GOT_ENTSIZE); 967 968 /* 969 * Add the GOTs data's offset. 970 */ 971 R2addr = R1addr + (uintptr_t)osp->os_outdata->d_buf; 972 973 DBG_CALL(Dbg_reloc_doact(ofl->ofl_lml, ELF_DBG_LD_ACT, 974 M_MACH, SHT_REL, arsp, R1addr, value, 975 ld_reloc_sym_name)); 976 977 /* 978 * And do it. 979 */ 980 if (ofl->ofl_flags1 & FLG_OF1_ENCDIFF) 981 *(Xword *)R2addr = ld_bswap_Xword(value); 982 else 983 *(Xword *)R2addr = value; 984 continue; 985 986 } else if (IS_GOT_BASED(arsp->rel_rtype) && 987 ((flags & FLG_OF_RELOBJ) == 0)) { 988 value -= ofl->ofl_osgot->os_shdr->sh_addr; 989 990 } else if (IS_GOT_PC(arsp->rel_rtype) && 991 ((flags & FLG_OF_RELOBJ) == 0)) { 992 value = (Xword)(ofl->ofl_osgot->os_shdr->sh_addr) - 993 refaddr; 994 995 } else if ((IS_PC_RELATIVE(arsp->rel_rtype)) && 996 (((flags & FLG_OF_RELOBJ) == 0) || 997 (osp == sdp->sd_isc->is_osdesc))) { 998 value -= refaddr; 999 1000 } else if (IS_TLS_INS(arsp->rel_rtype) && 1001 IS_GOT_RELATIVE(arsp->rel_rtype) && 1002 ((flags & FLG_OF_RELOBJ) == 0)) { 1003 Gotndx *gnp; 1004 1005 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, NULL); 1006 assert(gnp); 1007 value = (Xword)gnp->gn_gotndx * M_GOT_ENTSIZE; 1008 if (arsp->rel_rtype == R_386_TLS_IE) { 1009 value += ofl->ofl_osgot->os_shdr->sh_addr; 1010 } 1011 1012 } else if (IS_GOT_RELATIVE(arsp->rel_rtype) && 1013 ((flags & FLG_OF_RELOBJ) == 0)) { 1014 Gotndx *gnp; 1015 1016 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, 1017 GOT_REF_GENERIC, ofl, NULL); 1018 assert(gnp); 1019 value = (Xword)gnp->gn_gotndx * M_GOT_ENTSIZE; 1020 1021 } else if ((arsp->rel_flags & FLG_REL_STLS) && 1022 ((flags & FLG_OF_RELOBJ) == 0)) { 1023 Xword tlsstatsize; 1024 1025 /* 1026 * This is the LE TLS reference model. Static 1027 * offset is hard-coded. 1028 */ 1029 tlsstatsize = S_ROUND(ofl->ofl_tlsphdr->p_memsz, 1030 M_TLSSTATALIGN); 1031 value = tlsstatsize - value; 1032 1033 /* 1034 * Since this code is fixed up, it assumes a 1035 * negative offset that can be added to the 1036 * thread pointer. 1037 */ 1038 if ((arsp->rel_rtype == R_386_TLS_LDO_32) || 1039 (arsp->rel_rtype == R_386_TLS_LE)) 1040 value = -value; 1041 } 1042 1043 if (arsp->rel_isdesc->is_file) 1044 ifl_name = arsp->rel_isdesc->is_file->ifl_name; 1045 else 1046 ifl_name = MSG_INTL(MSG_STR_NULL); 1047 1048 /* 1049 * Make sure we have data to relocate. Compiler and assembler 1050 * developers have been known to generate relocations against 1051 * invalid sections (normally .bss), so for their benefit give 1052 * them sufficient information to help analyze the problem. 1053 * End users should never see this. 1054 */ 1055 if (arsp->rel_isdesc->is_indata->d_buf == 0) { 1056 Conv_inv_buf_t inv_buf; 1057 1058 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_REL_EMPTYSEC), 1059 conv_reloc_386_type(arsp->rel_rtype, 0, &inv_buf), 1060 ifl_name, ld_reloc_sym_name(arsp), 1061 EC_WORD(arsp->rel_isdesc->is_scnndx), 1062 arsp->rel_isdesc->is_name); 1063 return (S_ERROR); 1064 } 1065 1066 /* 1067 * Get the address of the data item we need to modify. 1068 */ 1069 addr = (uchar_t *)((uintptr_t)arsp->rel_roffset + 1070 (uintptr_t)_elf_getxoff(arsp->rel_isdesc->is_indata)); 1071 1072 DBG_CALL(Dbg_reloc_doact(ofl->ofl_lml, ELF_DBG_LD_ACT, 1073 M_MACH, SHT_REL, arsp, EC_NATPTR(addr), value, 1074 ld_reloc_sym_name)); 1075 addr += (uintptr_t)osp->os_outdata->d_buf; 1076 1077 if ((((uintptr_t)addr - (uintptr_t)ofl->ofl_nehdr) > 1078 ofl->ofl_size) || (arsp->rel_roffset > 1079 osp->os_shdr->sh_size)) { 1080 Conv_inv_buf_t inv_buf; 1081 int class; 1082 1083 if (((uintptr_t)addr - (uintptr_t)ofl->ofl_nehdr) > 1084 ofl->ofl_size) 1085 class = ERR_FATAL; 1086 else 1087 class = ERR_WARNING; 1088 1089 ld_eprintf(ofl, class, MSG_INTL(MSG_REL_INVALOFFSET), 1090 conv_reloc_386_type(arsp->rel_rtype, 0, &inv_buf), 1091 ifl_name, EC_WORD(arsp->rel_isdesc->is_scnndx), 1092 arsp->rel_isdesc->is_name, ld_reloc_sym_name(arsp), 1093 EC_ADDR((uintptr_t)addr - 1094 (uintptr_t)ofl->ofl_nehdr)); 1095 1096 if (class == ERR_FATAL) { 1097 return_code = S_ERROR; 1098 continue; 1099 } 1100 } 1101 1102 /* 1103 * The relocation is additive. Ignore the previous symbol 1104 * value if this local partial symbol is expanded. 1105 */ 1106 if (moved) 1107 value -= *addr; 1108 1109 /* 1110 * If we have a replacement value for the relocation 1111 * target, put it in place now. 1112 */ 1113 if (arsp->rel_flags & FLG_REL_NADDEND) { 1114 Xword addend = arsp->rel_raddend; 1115 1116 if (ld_reloc_targval_set(ofl, arsp, addr, addend) == 0) 1117 return (S_ERROR); 1118 } 1119 1120 /* 1121 * If '-z noreloc' is specified - skip the do_reloc_ld stage. 1122 */ 1123 if (OFL_DO_RELOC(ofl)) { 1124 if (do_reloc_ld(arsp, addr, &value, ld_reloc_sym_name, 1125 ifl_name, OFL_SWAP_RELOC_DATA(ofl, arsp), 1126 ofl->ofl_lml) == 0) { 1127 ofl->ofl_flags |= FLG_OF_FATAL; 1128 return_code = S_ERROR; 1129 } 1130 } 1131 } 1132 return (return_code); 1133 } 1134 1135 /* 1136 * Add an output relocation record. 1137 */ 1138 static uintptr_t 1139 ld_add_outrel(Word flags, Rel_desc *rsp, Ofl_desc *ofl) 1140 { 1141 Rel_desc *orsp; 1142 Sym_desc *sdp = rsp->rel_sym; 1143 1144 /* 1145 * Static executables *do not* want any relocations against them. 1146 * Since our engine still creates relocations against a WEAK UNDEFINED 1147 * symbol in a static executable, it's best to disable them here 1148 * instead of through out the relocation code. 1149 */ 1150 if (OFL_IS_STATIC_EXEC(ofl)) 1151 return (1); 1152 1153 /* 1154 * If the symbol will be reduced, we can't leave outstanding 1155 * relocations against it, as nothing will ever be able to satisfy them 1156 * (and the symbol won't be in .dynsym 1157 */ 1158 if ((sdp != NULL) && 1159 (sdp->sd_sym->st_shndx == SHN_UNDEF) && 1160 (rsp->rel_rtype != M_R_NONE) && 1161 (rsp->rel_rtype != M_R_RELATIVE)) { 1162 if (ld_sym_reducable(ofl, sdp)) 1163 return (1); 1164 } 1165 1166 /* 1167 * If we are adding a output relocation against a section 1168 * symbol (non-RELATIVE) then mark that section. These sections 1169 * will be added to the .dynsym symbol table. 1170 */ 1171 if (sdp && (rsp->rel_rtype != M_R_RELATIVE) && 1172 ((flags & FLG_REL_SCNNDX) || 1173 (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION))) { 1174 1175 /* 1176 * If this is a COMMON symbol - no output section 1177 * exists yet - (it's created as part of sym_validate()). 1178 * So - we mark here that when it's created it should 1179 * be tagged with the FLG_OS_OUTREL flag. 1180 */ 1181 if ((sdp->sd_flags & FLG_SY_SPECSEC) && 1182 (sdp->sd_sym->st_shndx == SHN_COMMON)) { 1183 if (ELF_ST_TYPE(sdp->sd_sym->st_info) != STT_TLS) 1184 ofl->ofl_flags1 |= FLG_OF1_BSSOREL; 1185 else 1186 ofl->ofl_flags1 |= FLG_OF1_TLSOREL; 1187 } else { 1188 Os_desc *osp; 1189 Is_desc *isp = sdp->sd_isc; 1190 1191 if (isp && ((osp = isp->is_osdesc) != NULL) && 1192 ((osp->os_flags & FLG_OS_OUTREL) == 0)) { 1193 ofl->ofl_dynshdrcnt++; 1194 osp->os_flags |= FLG_OS_OUTREL; 1195 } 1196 } 1197 } 1198 1199 /* Enter it into the output relocation cache */ 1200 if ((orsp = ld_reloc_enter(ofl, &ofl->ofl_outrels, rsp, flags)) == NULL) 1201 return (S_ERROR); 1202 1203 if (flags & FLG_REL_GOT) 1204 ofl->ofl_relocgotsz += (Xword)sizeof (Rel); 1205 else if (flags & FLG_REL_PLT) 1206 ofl->ofl_relocpltsz += (Xword)sizeof (Rel); 1207 else if (flags & FLG_REL_BSS) 1208 ofl->ofl_relocbsssz += (Xword)sizeof (Rel); 1209 else if (flags & FLG_REL_NOINFO) 1210 ofl->ofl_relocrelsz += (Xword)sizeof (Rel); 1211 else 1212 RELAUX_GET_OSDESC(orsp)->os_szoutrels += (Xword)sizeof (Rel); 1213 1214 if (orsp->rel_rtype == M_R_RELATIVE) 1215 ofl->ofl_relocrelcnt++; 1216 1217 /* 1218 * We don't perform sorting on PLT relocations because 1219 * they have already been assigned a PLT index and if we 1220 * were to sort them we would have to re-assign the plt indexes. 1221 */ 1222 if (!(flags & FLG_REL_PLT)) 1223 ofl->ofl_reloccnt++; 1224 1225 /* 1226 * Insure a GLOBAL_OFFSET_TABLE is generated if required. 1227 */ 1228 if (IS_GOT_REQUIRED(orsp->rel_rtype)) 1229 ofl->ofl_flags |= FLG_OF_BLDGOT; 1230 1231 /* 1232 * Identify and possibly warn of a displacement relocation. 1233 */ 1234 if (orsp->rel_flags & FLG_REL_DISP) { 1235 ofl->ofl_dtflags_1 |= DF_1_DISPRELPND; 1236 1237 if (ofl->ofl_flags & FLG_OF_VERBOSE) 1238 ld_disp_errmsg(MSG_INTL(MSG_REL_DISPREL4), orsp, ofl); 1239 } 1240 DBG_CALL(Dbg_reloc_ors_entry(ofl->ofl_lml, ELF_DBG_LD, SHT_REL, 1241 M_MACH, orsp)); 1242 return (1); 1243 } 1244 1245 /* 1246 * process relocation for a LOCAL symbol 1247 */ 1248 static uintptr_t 1249 ld_reloc_local(Rel_desc * rsp, Ofl_desc * ofl) 1250 { 1251 ofl_flag_t flags = ofl->ofl_flags; 1252 Sym_desc *sdp = rsp->rel_sym; 1253 Word shndx = sdp->sd_sym->st_shndx; 1254 1255 /* 1256 * if ((shared object) and (not pc relative relocation) and 1257 * (not against ABS symbol)) 1258 * then 1259 * build R_386_RELATIVE 1260 * fi 1261 */ 1262 if ((flags & FLG_OF_SHAROBJ) && (rsp->rel_flags & FLG_REL_LOAD) && 1263 !(IS_PC_RELATIVE(rsp->rel_rtype)) && !(IS_SIZE(rsp->rel_rtype)) && 1264 !(IS_GOT_BASED(rsp->rel_rtype)) && 1265 !(rsp->rel_isdesc != NULL && 1266 (rsp->rel_isdesc->is_shdr->sh_type == SHT_SUNW_dof)) && 1267 (((sdp->sd_flags & FLG_SY_SPECSEC) == 0) || 1268 (shndx != SHN_ABS) || (sdp->sd_aux && sdp->sd_aux->sa_symspec))) { 1269 Word ortype = rsp->rel_rtype; 1270 1271 rsp->rel_rtype = R_386_RELATIVE; 1272 if (ld_add_outrel(0, rsp, ofl) == S_ERROR) 1273 return (S_ERROR); 1274 rsp->rel_rtype = ortype; 1275 } 1276 1277 /* 1278 * If the relocation is against a 'non-allocatable' section 1279 * and we can not resolve it now - then give a warning 1280 * message. 1281 * 1282 * We can not resolve the symbol if either: 1283 * a) it's undefined 1284 * b) it's defined in a shared library and a 1285 * COPY relocation hasn't moved it to the executable 1286 * 1287 * Note: because we process all of the relocations against the 1288 * text segment before any others - we know whether 1289 * or not a copy relocation will be generated before 1290 * we get here (see reloc_init()->reloc_segments()). 1291 */ 1292 if (!(rsp->rel_flags & FLG_REL_LOAD) && 1293 ((shndx == SHN_UNDEF) || 1294 ((sdp->sd_ref == REF_DYN_NEED) && 1295 ((sdp->sd_flags & FLG_SY_MVTOCOMM) == 0)))) { 1296 Conv_inv_buf_t inv_buf; 1297 Os_desc *osp = RELAUX_GET_OSDESC(rsp); 1298 1299 /* 1300 * If the relocation is against a SHT_SUNW_ANNOTATE 1301 * section - then silently ignore that the relocation 1302 * can not be resolved. 1303 */ 1304 if (osp && (osp->os_shdr->sh_type == SHT_SUNW_ANNOTATE)) 1305 return (0); 1306 ld_eprintf(ofl, ERR_WARNING, MSG_INTL(MSG_REL_EXTERNSYM), 1307 conv_reloc_386_type(rsp->rel_rtype, 0, &inv_buf), 1308 rsp->rel_isdesc->is_file->ifl_name, 1309 ld_reloc_sym_name(rsp), osp->os_name); 1310 return (1); 1311 } 1312 1313 /* 1314 * Perform relocation. 1315 */ 1316 return (ld_add_actrel(0, rsp, ofl)); 1317 } 1318 1319 static uintptr_t 1320 ld_reloc_TLS(Boolean local, Rel_desc * rsp, Ofl_desc * ofl) 1321 { 1322 Word rtype = rsp->rel_rtype; 1323 Sym_desc *sdp = rsp->rel_sym; 1324 ofl_flag_t flags = ofl->ofl_flags; 1325 Gotndx *gnp; 1326 1327 /* 1328 * If we're building an executable - use either the IE or LE access 1329 * model. If we're building a shared object process any IE model. 1330 */ 1331 if ((flags & FLG_OF_EXEC) || (IS_TLS_IE(rtype))) { 1332 /* 1333 * Set the DF_STATIC_TLS flag. 1334 */ 1335 ofl->ofl_dtflags |= DF_STATIC_TLS; 1336 1337 if (!local || ((flags & FLG_OF_EXEC) == 0)) { 1338 /* 1339 * Assign a GOT entry for static TLS references. 1340 */ 1341 if ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs, 1342 GOT_REF_TLSIE, ofl, NULL)) == NULL) { 1343 1344 if (ld_assign_got_TLS(local, rsp, ofl, sdp, 1345 gnp, GOT_REF_TLSIE, FLG_REL_STLS, 1346 rtype, R_386_TLS_TPOFF, 0) == S_ERROR) 1347 return (S_ERROR); 1348 } 1349 1350 /* 1351 * IE access model. 1352 */ 1353 if (IS_TLS_IE(rtype)) { 1354 if (ld_add_actrel(FLG_REL_STLS, 1355 rsp, ofl) == S_ERROR) 1356 return (S_ERROR); 1357 1358 /* 1359 * A non-pic shared object needs to adjust the 1360 * active relocation (indntpoff). 1361 */ 1362 if (((flags & FLG_OF_EXEC) == 0) && 1363 (rtype == R_386_TLS_IE)) { 1364 rsp->rel_rtype = R_386_RELATIVE; 1365 return (ld_add_outrel(0, rsp, ofl)); 1366 } 1367 return (1); 1368 } 1369 1370 /* 1371 * Fixups are required for other executable models. 1372 */ 1373 return (ld_add_actrel((FLG_REL_TLSFIX | FLG_REL_STLS), 1374 rsp, ofl)); 1375 } 1376 1377 /* 1378 * LE access model. 1379 */ 1380 if (IS_TLS_LE(rtype) || (rtype == R_386_TLS_LDO_32)) 1381 return (ld_add_actrel(FLG_REL_STLS, rsp, ofl)); 1382 1383 return (ld_add_actrel((FLG_REL_TLSFIX | FLG_REL_STLS), 1384 rsp, ofl)); 1385 } 1386 1387 /* 1388 * Building a shared object. 1389 * 1390 * Assign a GOT entry for a dynamic TLS reference. 1391 */ 1392 if (IS_TLS_LD(rtype) && ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs, 1393 GOT_REF_TLSLD, ofl, NULL)) == NULL)) { 1394 1395 if (ld_assign_got_TLS(local, rsp, ofl, sdp, gnp, GOT_REF_TLSLD, 1396 FLG_REL_MTLS, rtype, R_386_TLS_DTPMOD32, 0) == S_ERROR) 1397 return (S_ERROR); 1398 1399 } else if (IS_TLS_GD(rtype) && ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs, 1400 GOT_REF_TLSGD, ofl, NULL)) == NULL)) { 1401 1402 if (ld_assign_got_TLS(local, rsp, ofl, sdp, gnp, GOT_REF_TLSGD, 1403 FLG_REL_DTLS, rtype, R_386_TLS_DTPMOD32, 1404 R_386_TLS_DTPOFF32) == S_ERROR) 1405 return (S_ERROR); 1406 } 1407 1408 /* 1409 * For GD/LD TLS reference - TLS_{GD,LD}_CALL, this will eventually 1410 * cause a call to __tls_get_addr(). Convert this relocation to that 1411 * symbol now, and prepare for the PLT magic. 1412 */ 1413 if ((rtype == R_386_TLS_GD_PLT) || (rtype == R_386_TLS_LDM_PLT)) { 1414 Sym_desc *tlsgetsym; 1415 1416 if ((tlsgetsym = ld_sym_add_u(MSG_ORIG(MSG_SYM_TLSGETADDR_UU), 1417 ofl, MSG_STR_TLSREL)) == (Sym_desc *)S_ERROR) 1418 return (S_ERROR); 1419 1420 rsp->rel_sym = tlsgetsym; 1421 rsp->rel_rtype = R_386_PLT32; 1422 1423 if (ld_reloc_plt(rsp, ofl) == S_ERROR) 1424 return (S_ERROR); 1425 1426 rsp->rel_sym = sdp; 1427 rsp->rel_rtype = rtype; 1428 return (1); 1429 } 1430 1431 if (IS_TLS_LD(rtype)) 1432 return (ld_add_actrel(FLG_REL_MTLS, rsp, ofl)); 1433 1434 return (ld_add_actrel(FLG_REL_DTLS, rsp, ofl)); 1435 } 1436 1437 /* ARGSUSED4 */ 1438 static uintptr_t 1439 ld_assign_got_ndx(Alist **alpp, Gotndx *pgnp, Gotref gref, Ofl_desc *ofl, 1440 Rel_desc *rsp, Sym_desc *sdp) 1441 { 1442 Gotndx gn, *gnp; 1443 uint_t gotents; 1444 1445 if (pgnp) 1446 return (1); 1447 1448 if ((gref == GOT_REF_TLSGD) || (gref == GOT_REF_TLSLD)) 1449 gotents = 2; 1450 else 1451 gotents = 1; 1452 1453 gn.gn_addend = 0; 1454 gn.gn_gotndx = ofl->ofl_gotcnt; 1455 gn.gn_gotref = gref; 1456 1457 ofl->ofl_gotcnt += gotents; 1458 1459 if (gref == GOT_REF_TLSLD) { 1460 if (ofl->ofl_tlsldgotndx == NULL) { 1461 if ((gnp = libld_malloc(sizeof (Gotndx))) == NULL) 1462 return (S_ERROR); 1463 (void) memcpy(gnp, &gn, sizeof (Gotndx)); 1464 ofl->ofl_tlsldgotndx = gnp; 1465 } 1466 return (1); 1467 } 1468 1469 /* 1470 * GOT indexes are maintained on an Alist, where there is typically 1471 * only one index. The usage of this list is to scan the list to find 1472 * an index, and then apply that index immediately to a relocation. 1473 * Thus there are no external references to these GOT index structures 1474 * that can be compromised by the Alist being reallocated. 1475 */ 1476 if (alist_append(alpp, &gn, sizeof (Gotndx), AL_CNT_SDP_GOT) == NULL) 1477 return (S_ERROR); 1478 1479 return (1); 1480 } 1481 1482 static void 1483 ld_assign_plt_ndx(Sym_desc * sdp, Ofl_desc *ofl) 1484 { 1485 sdp->sd_aux->sa_PLTndx = 1 + ofl->ofl_pltcnt++; 1486 sdp->sd_aux->sa_PLTGOTndx = ofl->ofl_gotcnt++; 1487 ofl->ofl_flags |= FLG_OF_BLDGOT; 1488 } 1489 1490 /* 1491 * Initializes .got[0] with the _DYNAMIC symbol value. 1492 */ 1493 static uintptr_t 1494 ld_fillin_gotplt(Ofl_desc *ofl) 1495 { 1496 ofl_flag_t flags = ofl->ofl_flags; 1497 int bswap = (ofl->ofl_flags1 & FLG_OF1_ENCDIFF) != 0; 1498 1499 if (ofl->ofl_osgot) { 1500 Sym_desc *sdp; 1501 1502 if ((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_DYNAMIC_U), 1503 SYM_NOHASH, NULL, ofl)) != NULL) { 1504 uchar_t *genptr; 1505 1506 genptr = ((uchar_t *)ofl->ofl_osgot->os_outdata->d_buf + 1507 (M_GOT_XDYNAMIC * M_GOT_ENTSIZE)); 1508 /* LINTED */ 1509 *(Word *)genptr = (Word)sdp->sd_sym->st_value; 1510 if (bswap) 1511 /* LINTED */ 1512 *(Word *)genptr = 1513 /* LINTED */ 1514 ld_bswap_Word(*(Word *)genptr); 1515 } 1516 } 1517 1518 /* 1519 * Fill in the reserved slot in the procedure linkage table the first 1520 * entry is: 1521 * if (building a.out) { 1522 * PUSHL got[1] # the address of the link map entry 1523 * JMP * got[2] # the address of rtbinder 1524 * } else { 1525 * PUSHL got[1]@GOT(%ebx) # the address of the link map entry 1526 * JMP * got[2]@GOT(%ebx) # the address of rtbinder 1527 * } 1528 */ 1529 if ((flags & FLG_OF_DYNAMIC) && ofl->ofl_osplt) { 1530 uchar_t *pltent; 1531 1532 pltent = (uchar_t *)ofl->ofl_osplt->os_outdata->d_buf; 1533 if (!(flags & FLG_OF_SHAROBJ)) { 1534 pltent[0] = M_SPECIAL_INST; 1535 pltent[1] = M_PUSHL_DISP; 1536 pltent += 2; 1537 /* LINTED */ 1538 *(Word *)pltent = (Word)(ofl->ofl_osgot->os_shdr-> 1539 sh_addr + M_GOT_XLINKMAP * M_GOT_ENTSIZE); 1540 if (bswap) 1541 /* LINTED */ 1542 *(Word *)pltent = 1543 /* LINTED */ 1544 ld_bswap_Word(*(Word *)pltent); 1545 pltent += 4; 1546 pltent[0] = M_SPECIAL_INST; 1547 pltent[1] = M_JMP_DISP_IND; 1548 pltent += 2; 1549 /* LINTED */ 1550 *(Word *)pltent = (Word)(ofl->ofl_osgot->os_shdr-> 1551 sh_addr + M_GOT_XRTLD * M_GOT_ENTSIZE); 1552 if (bswap) 1553 /* LINTED */ 1554 *(Word *)pltent = 1555 /* LINTED */ 1556 ld_bswap_Word(*(Word *)pltent); 1557 } else { 1558 pltent[0] = M_SPECIAL_INST; 1559 pltent[1] = M_PUSHL_REG_DISP; 1560 pltent += 2; 1561 /* LINTED */ 1562 *(Word *)pltent = (Word)(M_GOT_XLINKMAP * 1563 M_GOT_ENTSIZE); 1564 if (bswap) 1565 /* LINTED */ 1566 *(Word *)pltent = 1567 /* LINTED */ 1568 ld_bswap_Word(*(Word *)pltent); 1569 pltent += 4; 1570 pltent[0] = M_SPECIAL_INST; 1571 pltent[1] = M_JMP_REG_DISP_IND; 1572 pltent += 2; 1573 /* LINTED */ 1574 *(Word *)pltent = (Word)(M_GOT_XRTLD * 1575 M_GOT_ENTSIZE); 1576 if (bswap) 1577 /* LINTED */ 1578 *(Word *)pltent = 1579 /* LINTED */ 1580 ld_bswap_Word(*(Word *)pltent); 1581 } 1582 } 1583 return (1); 1584 } 1585 1586 1587 1588 /* 1589 * Template for generating "void (*)(void)" function 1590 */ 1591 static const uchar_t nullfunc_tmpl[] = { /* IA32 */ 1592 /* 0x00 */ 0xc3 /* ret */ 1593 }; 1594 1595 1596 1597 /* 1598 * Function used to provide fill padding in SHF_EXECINSTR sections 1599 * 1600 * entry: 1601 * 1602 * base - base address of section being filled 1603 * offset - starting offset for fill within memory referenced by base 1604 * cnt - # bytes to be filled 1605 * 1606 * exit: 1607 * The fill has been completed. 1608 */ 1609 static void 1610 execfill(void *base, off_t off, size_t cnt) 1611 { 1612 /* 1613 * 0x90 is an X86 NOP instruction in both 32 and 64-bit worlds. 1614 * There are no alignment constraints. 1615 */ 1616 (void) memset(off + (char *)base, 0x90, cnt); 1617 } 1618 1619 1620 /* 1621 * Return the ld_targ definition for this target. 1622 */ 1623 const Target * 1624 ld_targ_init_x86(void) 1625 { 1626 static const Target _ld_targ = { 1627 { /* Target_mach */ 1628 M_MACH, /* m_mach */ 1629 M_MACHPLUS, /* m_machplus */ 1630 M_FLAGSPLUS, /* m_flagsplus */ 1631 M_CLASS, /* m_class */ 1632 M_DATA, /* m_data */ 1633 1634 M_SEGM_ALIGN, /* m_segm_align */ 1635 M_SEGM_ORIGIN, /* m_segm_origin */ 1636 M_SEGM_AORIGIN, /* m_segm_aorigin */ 1637 M_DATASEG_PERM, /* m_dataseg_perm */ 1638 M_STACK_PERM, /* m_stack_perm */ 1639 M_WORD_ALIGN, /* m_word_align */ 1640 MSG_ORIG(MSG_PTH_RTLD), /* m_def_interp */ 1641 1642 /* Relocation type codes */ 1643 M_R_ARRAYADDR, /* m_r_arrayaddr */ 1644 M_R_COPY, /* m_r_copy */ 1645 M_R_GLOB_DAT, /* m_r_glob_dat */ 1646 M_R_JMP_SLOT, /* m_r_jmp_slot */ 1647 M_R_NUM, /* m_r_num */ 1648 M_R_NONE, /* m_r_none */ 1649 M_R_RELATIVE, /* m_r_relative */ 1650 M_R_REGISTER, /* m_r_register */ 1651 1652 /* Relocation related constants */ 1653 M_REL_DT_COUNT, /* m_rel_dt_count */ 1654 M_REL_DT_ENT, /* m_rel_dt_ent */ 1655 M_REL_DT_SIZE, /* m_rel_dt_size */ 1656 M_REL_DT_TYPE, /* m_rel_dt_type */ 1657 M_REL_SHT_TYPE, /* m_rel_sht_type */ 1658 1659 /* GOT related constants */ 1660 M_GOT_ENTSIZE, /* m_got_entsize */ 1661 M_GOT_XNumber, /* m_got_xnumber */ 1662 1663 /* PLT related constants */ 1664 M_PLT_ALIGN, /* m_plt_align */ 1665 M_PLT_ENTSIZE, /* m_plt_entsize */ 1666 M_PLT_RESERVSZ, /* m_plt_reservsz */ 1667 M_PLT_SHF_FLAGS, /* m_plt_shf_flags */ 1668 1669 /* Section type of .eh_frame/.eh_frame_hdr sections */ 1670 SHT_PROGBITS, /* m_sht_unwind */ 1671 1672 M_DT_REGISTER, /* m_dt_register */ 1673 }, 1674 { /* Target_machid */ 1675 M_ID_ARRAY, /* id_array */ 1676 M_ID_BSS, /* id_bss */ 1677 M_ID_CAP, /* id_cap */ 1678 M_ID_CAPINFO, /* id_capinfo */ 1679 M_ID_CAPCHAIN, /* id_capchain */ 1680 M_ID_DATA, /* id_data */ 1681 M_ID_DYNAMIC, /* id_dynamic */ 1682 M_ID_DYNSORT, /* id_dynsort */ 1683 M_ID_DYNSTR, /* id_dynstr */ 1684 M_ID_DYNSYM, /* id_dynsym */ 1685 M_ID_DYNSYM_NDX, /* id_dynsym_ndx */ 1686 M_ID_GOT, /* id_got */ 1687 M_ID_UNKNOWN, /* id_gotdata (unused) */ 1688 M_ID_HASH, /* id_hash */ 1689 M_ID_INTERP, /* id_interp */ 1690 M_ID_LBSS, /* id_lbss */ 1691 M_ID_LDYNSYM, /* id_ldynsym */ 1692 M_ID_NOTE, /* id_note */ 1693 M_ID_NULL, /* id_null */ 1694 M_ID_PLT, /* id_plt */ 1695 M_ID_REL, /* id_rel */ 1696 M_ID_STRTAB, /* id_strtab */ 1697 M_ID_SYMINFO, /* id_syminfo */ 1698 M_ID_SYMTAB, /* id_symtab */ 1699 M_ID_SYMTAB_NDX, /* id_symtab_ndx */ 1700 M_ID_TEXT, /* id_text */ 1701 M_ID_TLS, /* id_tls */ 1702 M_ID_TLSBSS, /* id_tlsbss */ 1703 M_ID_UNKNOWN, /* id_unknown */ 1704 M_ID_UNWIND, /* id_unwind */ 1705 M_ID_UNWINDHDR, /* id_unwindhdr */ 1706 M_ID_USER, /* id_user */ 1707 M_ID_VERSION, /* id_version */ 1708 }, 1709 { /* Target_nullfunc */ 1710 nullfunc_tmpl, /* nf_template */ 1711 sizeof (nullfunc_tmpl), /* nf_size */ 1712 }, 1713 { /* Target_fillfunc */ 1714 execfill /* ff_execfill */ 1715 }, 1716 { /* Target_machrel */ 1717 reloc_table, 1718 1719 ld_init_rel, /* mr_init_rel */ 1720 ld_mach_eflags, /* mr_mach_eflags */ 1721 ld_mach_make_dynamic, /* mr_mach_make_dynamic */ 1722 ld_mach_update_odynamic, /* mr_mach_update_odynamic */ 1723 ld_calc_plt_addr, /* mr_calc_plt_addr */ 1724 ld_perform_outreloc, /* mr_perform_outreloc */ 1725 ld_do_activerelocs, /* mr_do_activerelocs */ 1726 ld_add_outrel, /* mr_add_outrel */ 1727 NULL, /* mr_reloc_register */ 1728 ld_reloc_local, /* mr_reloc_local */ 1729 NULL, /* mr_reloc_GOTOP */ 1730 ld_reloc_TLS, /* mr_reloc_TLS */ 1731 NULL, /* mr_assign_got */ 1732 ld_find_got_ndx, /* mr_find_got_ndx */ 1733 ld_calc_got_offset, /* mr_calc_got_offset */ 1734 ld_assign_got_ndx, /* mr_assign_got_ndx */ 1735 ld_assign_plt_ndx, /* mr_assign_plt_ndx */ 1736 NULL, /* mr_allocate_got */ 1737 ld_fillin_gotplt, /* mr_fillin_gotplt */ 1738 }, 1739 { /* Target_machsym */ 1740 NULL, /* ms_reg_check */ 1741 NULL, /* ms_mach_sym_typecheck */ 1742 NULL, /* ms_is_regsym */ 1743 NULL, /* ms_reg_find */ 1744 NULL /* ms_reg_enter */ 1745 } 1746 }; 1747 1748 return (&_ld_targ); 1749 } 1750