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) 2004, 2010, Oracle and/or its affiliates. All rights reserved. 24 */ 25 26 /* Get the x86 version of the relocation engine */ 27 #define DO_RELOC_LIBLD_X86 28 29 #include <string.h> 30 #include <stdio.h> 31 #include <strings.h> 32 #include <sys/elf_amd64.h> 33 #include <debug.h> 34 #include <reloc.h> 35 #include <i386/machdep_x86.h> 36 #include "msg.h" 37 #include "_libld.h" 38 39 /* 40 * This module uses do_reloc_ld() to execute several synthesized relocations. 41 * That function expects to be passed two things that we need to construct 42 * here: 43 * 44 * 1) A Rel_desc descriptor for each relocation type, from which the 45 * rel_rtype field, and nothing else, is obtained. This is easily 46 * handled by constructing the necessary descriptors. 47 * 48 * 2) A function, which called with the Rel_desc descriptor, returns 49 * a string representing the name of the symbol associated with 50 * the descriptor. The usual function for this is ld_reloc_sym_name(). 51 * However, that function will not work in this case, as these synthetic 52 * relocations do not have an associated symbol. We supply the 53 * syn_rdesc_sym_name() function to simply return the fixed name. 54 */ 55 static Rel_desc rdesc_r_amd64_gotpcrel = { 56 NULL, NULL, NULL, 0, 0, 0, R_AMD64_GOTPCREL }; 57 static Rel_desc rdesc_r_amd64_32 = { 58 NULL, NULL, NULL, 0, 0, 0, R_AMD64_32 }; 59 static Rel_desc rdesc_r_amd64_pc32 = { 60 NULL, NULL, NULL, 0, 0, 0, R_AMD64_PC32 }; 61 62 /*ARGSUSED*/ 63 static const char * 64 syn_rdesc_sym_name(Rel_desc *rdesc) 65 { 66 return (MSG_ORIG(MSG_SYM_PLTENT)); 67 } 68 69 /* 70 * Search the GOT index list for a GOT entry with a matching reference and the 71 * proper addend. 72 */ 73 static Gotndx * 74 ld_find_got_ndx(Alist *alp, Gotref gref, Ofl_desc *ofl, Rel_desc *rdesc) 75 { 76 Aliste idx; 77 Gotndx *gnp; 78 79 assert(rdesc != 0); 80 81 if ((gref == GOT_REF_TLSLD) && ofl->ofl_tlsldgotndx) 82 return (ofl->ofl_tlsldgotndx); 83 84 for (ALIST_TRAVERSE(alp, idx, gnp)) { 85 if ((rdesc->rel_raddend == gnp->gn_addend) && 86 (gnp->gn_gotref == gref)) { 87 return (gnp); 88 } 89 } 90 return (NULL); 91 } 92 93 static Xword 94 ld_calc_got_offset(Rel_desc *rdesc, Ofl_desc *ofl) 95 { 96 Os_desc *osp = ofl->ofl_osgot; 97 Sym_desc *sdp = rdesc->rel_sym; 98 Xword gotndx; 99 Gotref gref; 100 Gotndx *gnp; 101 102 if (rdesc->rel_flags & FLG_REL_DTLS) 103 gref = GOT_REF_TLSGD; 104 else if (rdesc->rel_flags & FLG_REL_MTLS) 105 gref = GOT_REF_TLSLD; 106 else if (rdesc->rel_flags & FLG_REL_STLS) 107 gref = GOT_REF_TLSIE; 108 else 109 gref = GOT_REF_GENERIC; 110 111 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, rdesc); 112 assert(gnp); 113 114 gotndx = (Xword)gnp->gn_gotndx; 115 116 if ((rdesc->rel_flags & FLG_REL_DTLS) && 117 (rdesc->rel_rtype == R_AMD64_DTPOFF64)) 118 gotndx++; 119 120 return ((Xword)(osp->os_shdr->sh_addr + (gotndx * M_GOT_ENTSIZE))); 121 } 122 123 static Word 124 ld_init_rel(Rel_desc *reld, Word *typedata, void *reloc) 125 { 126 Rela *rel = (Rela *)reloc; 127 128 /* LINTED */ 129 reld->rel_rtype = (Word)ELF_R_TYPE(rel->r_info, M_MACH); 130 reld->rel_roffset = rel->r_offset; 131 reld->rel_raddend = rel->r_addend; 132 *typedata = 0; 133 134 reld->rel_flags |= FLG_REL_RELA; 135 136 return ((Word)ELF_R_SYM(rel->r_info)); 137 } 138 139 static void 140 ld_mach_eflags(Ehdr *ehdr, Ofl_desc *ofl) 141 { 142 ofl->ofl_dehdr->e_flags |= ehdr->e_flags; 143 } 144 145 static void 146 ld_mach_make_dynamic(Ofl_desc *ofl, size_t *cnt) 147 { 148 if (!(ofl->ofl_flags & FLG_OF_RELOBJ)) { 149 /* 150 * Create this entry if we are going to create a PLT table. 151 */ 152 if (ofl->ofl_pltcnt) 153 (*cnt)++; /* DT_PLTGOT */ 154 } 155 } 156 157 static void 158 ld_mach_update_odynamic(Ofl_desc *ofl, Dyn **dyn) 159 { 160 if (((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) && ofl->ofl_pltcnt) { 161 (*dyn)->d_tag = DT_PLTGOT; 162 if (ofl->ofl_osgot) 163 (*dyn)->d_un.d_ptr = ofl->ofl_osgot->os_shdr->sh_addr; 164 else 165 (*dyn)->d_un.d_ptr = 0; 166 (*dyn)++; 167 } 168 } 169 170 static Xword 171 ld_calc_plt_addr(Sym_desc *sdp, Ofl_desc *ofl) 172 { 173 Xword value; 174 175 value = (Xword)(ofl->ofl_osplt->os_shdr->sh_addr) + 176 M_PLT_RESERVSZ + ((sdp->sd_aux->sa_PLTndx - 1) * M_PLT_ENTSIZE); 177 return (value); 178 } 179 180 /* 181 * Build a single plt entry - code is: 182 * JMP *name1@GOTPCREL(%rip) 183 * PUSHL $index 184 * JMP .PLT0 185 */ 186 static uchar_t pltn_entry[M_PLT_ENTSIZE] = { 187 /* 0x00 jmpq *name1@GOTPCREL(%rip) */ 0xff, 0x25, 0x00, 0x00, 0x00, 0x00, 188 /* 0x06 pushq $index */ 0x68, 0x00, 0x00, 0x00, 0x00, 189 /* 0x0b jmpq .plt0(%rip) */ 0xe9, 0x00, 0x00, 0x00, 0x00 190 /* 0x10 */ 191 }; 192 193 static uintptr_t 194 plt_entry(Ofl_desc * ofl, Sym_desc * sdp) 195 { 196 uchar_t *plt0, *pltent, *gotent; 197 Sword plt_off; 198 Word got_off; 199 Xword val1; 200 int bswap = (ofl->ofl_flags1 & FLG_OF1_ENCDIFF) != 0; 201 202 got_off = sdp->sd_aux->sa_PLTGOTndx * M_GOT_ENTSIZE; 203 plt_off = M_PLT_RESERVSZ + ((sdp->sd_aux->sa_PLTndx - 1) * 204 M_PLT_ENTSIZE); 205 plt0 = (uchar_t *)(ofl->ofl_osplt->os_outdata->d_buf); 206 pltent = plt0 + plt_off; 207 gotent = (uchar_t *)(ofl->ofl_osgot->os_outdata->d_buf) + got_off; 208 209 bcopy(pltn_entry, pltent, sizeof (pltn_entry)); 210 /* 211 * Fill in the got entry with the address of the next instruction. 212 */ 213 /* LINTED */ 214 *(Word *)gotent = ofl->ofl_osplt->os_shdr->sh_addr + plt_off + 215 M_PLT_INSSIZE; 216 if (bswap) 217 /* LINTED */ 218 *(Word *)gotent = ld_bswap_Word(*(Word *)gotent); 219 220 /* 221 * If '-z noreloc' is specified - skip the do_reloc_ld 222 * stage. 223 */ 224 if (!OFL_DO_RELOC(ofl)) 225 return (1); 226 227 /* 228 * patchup: 229 * jmpq *name1@gotpcrel(%rip) 230 * 231 * NOTE: 0x06 represents next instruction. 232 */ 233 val1 = (ofl->ofl_osgot->os_shdr->sh_addr + got_off) - 234 (ofl->ofl_osplt->os_shdr->sh_addr + plt_off) - 0x06; 235 236 if (do_reloc_ld(&rdesc_r_amd64_gotpcrel, &pltent[0x02], &val1, 237 syn_rdesc_sym_name, MSG_ORIG(MSG_SPECFIL_PLTENT), bswap, 238 ofl->ofl_lml) == 0) { 239 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_PLT_PLTNFAIL), 240 sdp->sd_aux->sa_PLTndx, demangle(sdp->sd_name)); 241 return (S_ERROR); 242 } 243 244 /* 245 * patchup: 246 * pushq $pltndx 247 */ 248 val1 = (Xword)(sdp->sd_aux->sa_PLTndx - 1); 249 250 if (do_reloc_ld(&rdesc_r_amd64_32, &pltent[0x07], &val1, 251 syn_rdesc_sym_name, MSG_ORIG(MSG_SPECFIL_PLTENT), bswap, 252 ofl->ofl_lml) == 0) { 253 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_PLT_PLTNFAIL), 254 sdp->sd_aux->sa_PLTndx, demangle(sdp->sd_name)); 255 return (S_ERROR); 256 } 257 258 /* 259 * patchup: 260 * jmpq .plt0(%rip) 261 * NOTE: 0x10 represents next instruction. The rather complex 262 * series of casts is necessary to sign extend an offset into 263 * a 64-bit value while satisfying various compiler error 264 * checks. Handle with care. 265 */ 266 val1 = (Xword)((intptr_t)((uintptr_t)plt0 - 267 (uintptr_t)(&pltent[0x10]))); 268 269 if (do_reloc_ld(&rdesc_r_amd64_pc32, &pltent[0x0c], &val1, 270 syn_rdesc_sym_name, MSG_ORIG(MSG_SPECFIL_PLTENT), bswap, 271 ofl->ofl_lml) == 0) { 272 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_PLT_PLTNFAIL), 273 sdp->sd_aux->sa_PLTndx, demangle(sdp->sd_name)); 274 return (S_ERROR); 275 } 276 277 return (1); 278 } 279 280 static uintptr_t 281 ld_perform_outreloc(Rel_desc * orsp, Ofl_desc * ofl, Boolean *remain_seen) 282 { 283 Os_desc * relosp, * osp = 0; 284 Word ndx; 285 Xword roffset, value; 286 Sxword raddend; 287 Rela rea; 288 char *relbits; 289 Sym_desc * sdp, * psym = (Sym_desc *)0; 290 int sectmoved = 0; 291 292 raddend = orsp->rel_raddend; 293 sdp = orsp->rel_sym; 294 295 /* 296 * If the section this relocation is against has been discarded 297 * (-zignore), then also discard (skip) the relocation itself. 298 */ 299 if (orsp->rel_isdesc && ((orsp->rel_flags & 300 (FLG_REL_GOT | FLG_REL_BSS | FLG_REL_PLT | FLG_REL_NOINFO)) == 0) && 301 (orsp->rel_isdesc->is_flags & FLG_IS_DISCARD)) { 302 DBG_CALL(Dbg_reloc_discard(ofl->ofl_lml, M_MACH, orsp)); 303 return (1); 304 } 305 306 /* 307 * If this is a relocation against a move table, or expanded move 308 * table, adjust the relocation entries. 309 */ 310 if (RELAUX_GET_MOVE(orsp)) 311 ld_adj_movereloc(ofl, orsp); 312 313 /* 314 * If this is a relocation against a section then we need to adjust the 315 * raddend field to compensate for the new position of the input section 316 * within the new output section. 317 */ 318 if (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) { 319 if (ofl->ofl_parsyms && 320 (sdp->sd_isc->is_flags & FLG_IS_RELUPD) && 321 /* LINTED */ 322 (psym = ld_am_I_partial(orsp, orsp->rel_raddend))) { 323 DBG_CALL(Dbg_move_outsctadj(ofl->ofl_lml, psym)); 324 sectmoved = 1; 325 if (ofl->ofl_flags & FLG_OF_RELOBJ) 326 raddend = psym->sd_sym->st_value; 327 else 328 raddend = psym->sd_sym->st_value - 329 psym->sd_isc->is_osdesc->os_shdr->sh_addr; 330 /* LINTED */ 331 raddend += (Off)_elf_getxoff(psym->sd_isc->is_indata); 332 if (psym->sd_isc->is_shdr->sh_flags & SHF_ALLOC) 333 raddend += 334 psym->sd_isc->is_osdesc->os_shdr->sh_addr; 335 } else { 336 /* LINTED */ 337 raddend += (Off)_elf_getxoff(sdp->sd_isc->is_indata); 338 if (sdp->sd_isc->is_shdr->sh_flags & SHF_ALLOC) 339 raddend += 340 sdp->sd_isc->is_osdesc->os_shdr->sh_addr; 341 } 342 } 343 344 value = sdp->sd_sym->st_value; 345 346 if (orsp->rel_flags & FLG_REL_GOT) { 347 /* 348 * Note: for GOT relative relocations on amd64 349 * we discard the addend. It was relevant 350 * to the reference - not to the data item 351 * being referenced (ie: that -4 thing). 352 */ 353 raddend = 0; 354 osp = ofl->ofl_osgot; 355 roffset = ld_calc_got_offset(orsp, ofl); 356 357 } else if (orsp->rel_flags & FLG_REL_PLT) { 358 /* 359 * Note that relocations for PLT's actually 360 * cause a relocation againt the GOT. 361 */ 362 osp = ofl->ofl_osplt; 363 roffset = (ofl->ofl_osgot->os_shdr->sh_addr) + 364 sdp->sd_aux->sa_PLTGOTndx * M_GOT_ENTSIZE; 365 raddend = 0; 366 if (plt_entry(ofl, sdp) == S_ERROR) 367 return (S_ERROR); 368 369 } else if (orsp->rel_flags & FLG_REL_BSS) { 370 /* 371 * This must be a R_AMD64_COPY. For these set the roffset to 372 * point to the new symbols location. 373 */ 374 osp = ofl->ofl_isbss->is_osdesc; 375 roffset = value; 376 377 /* 378 * The raddend doesn't mean anything in a R_SPARC_COPY 379 * relocation. Null it out because it can confuse people. 380 */ 381 raddend = 0; 382 } else { 383 osp = RELAUX_GET_OSDESC(orsp); 384 385 /* 386 * Calculate virtual offset of reference point; equals offset 387 * into section + vaddr of section for loadable sections, or 388 * offset plus section displacement for nonloadable sections. 389 */ 390 roffset = orsp->rel_roffset + 391 (Off)_elf_getxoff(orsp->rel_isdesc->is_indata); 392 if (!(ofl->ofl_flags & FLG_OF_RELOBJ)) 393 roffset += orsp->rel_isdesc->is_osdesc-> 394 os_shdr->sh_addr; 395 } 396 397 if ((osp == 0) || ((relosp = osp->os_relosdesc) == 0)) 398 relosp = ofl->ofl_osrel; 399 400 /* 401 * Assign the symbols index for the output relocation. If the 402 * relocation refers to a SECTION symbol then it's index is based upon 403 * the output sections symbols index. Otherwise the index can be 404 * derived from the symbols index itself. 405 */ 406 if (orsp->rel_rtype == R_AMD64_RELATIVE) 407 ndx = STN_UNDEF; 408 else if ((orsp->rel_flags & FLG_REL_SCNNDX) || 409 (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION)) { 410 if (sectmoved == 0) { 411 /* 412 * Check for a null input section. This can 413 * occur if this relocation references a symbol 414 * generated by sym_add_sym(). 415 */ 416 if (sdp->sd_isc && sdp->sd_isc->is_osdesc) 417 ndx = sdp->sd_isc->is_osdesc->os_identndx; 418 else 419 ndx = sdp->sd_shndx; 420 } else 421 ndx = ofl->ofl_parexpnndx; 422 } else 423 ndx = sdp->sd_symndx; 424 425 /* 426 * Add the symbols 'value' to the addend field. 427 */ 428 if (orsp->rel_flags & FLG_REL_ADVAL) 429 raddend += value; 430 431 /* 432 * The addend field for R_AMD64_DTPMOD64 means nothing. The addend 433 * is propagated in the corresponding R_AMD64_DTPOFF64 relocation. 434 */ 435 if (orsp->rel_rtype == R_AMD64_DTPMOD64) 436 raddend = 0; 437 438 relbits = (char *)relosp->os_outdata->d_buf; 439 440 rea.r_info = ELF_R_INFO(ndx, orsp->rel_rtype); 441 rea.r_offset = roffset; 442 rea.r_addend = raddend; 443 DBG_CALL(Dbg_reloc_out(ofl, ELF_DBG_LD, SHT_RELA, &rea, relosp->os_name, 444 ld_reloc_sym_name(orsp))); 445 446 /* 447 * Assert we haven't walked off the end of our relocation table. 448 */ 449 assert(relosp->os_szoutrels <= relosp->os_shdr->sh_size); 450 451 (void) memcpy((relbits + relosp->os_szoutrels), 452 (char *)&rea, sizeof (Rela)); 453 relosp->os_szoutrels += (Xword)sizeof (Rela); 454 455 /* 456 * Determine if this relocation is against a non-writable, allocatable 457 * section. If so we may need to provide a text relocation diagnostic. 458 * Note that relocations against the .plt (R_AMD64_JUMP_SLOT) actually 459 * result in modifications to the .got. 460 */ 461 if (orsp->rel_rtype == R_AMD64_JUMP_SLOT) 462 osp = ofl->ofl_osgot; 463 464 ld_reloc_remain_entry(orsp, osp, ofl, remain_seen); 465 return (1); 466 } 467 468 /* 469 * amd64 Instructions for TLS processing 470 */ 471 static uchar_t tlsinstr_gd_ie[] = { 472 /* 473 * 0x00 movq %fs:0, %rax 474 */ 475 0x64, 0x48, 0x8b, 0x04, 0x25, 476 0x00, 0x00, 0x00, 0x00, 477 /* 478 * 0x09 addq x@gottpoff(%rip), %rax 479 */ 480 0x48, 0x03, 0x05, 0x00, 0x00, 481 0x00, 0x00 482 }; 483 484 static uchar_t tlsinstr_gd_le[] = { 485 /* 486 * 0x00 movq %fs:0, %rax 487 */ 488 0x64, 0x48, 0x8b, 0x04, 0x25, 489 0x00, 0x00, 0x00, 0x00, 490 /* 491 * 0x09 leaq x@gottpoff(%rip), %rax 492 */ 493 0x48, 0x8d, 0x80, 0x00, 0x00, 494 0x00, 0x00 495 }; 496 497 static uchar_t tlsinstr_ld_le[] = { 498 /* 499 * .byte 0x66 500 */ 501 0x66, 502 /* 503 * .byte 0x66 504 */ 505 0x66, 506 /* 507 * .byte 0x66 508 */ 509 0x66, 510 /* 511 * movq %fs:0, %rax 512 */ 513 0x64, 0x48, 0x8b, 0x04, 0x25, 514 0x00, 0x00, 0x00, 0x00 515 }; 516 517 #define REX_B 0x1 518 #define REX_X 0x2 519 #define REX_R 0x4 520 #define REX_W 0x8 521 #define REX_PREFIX 0x40 522 523 #define REX_RW (REX_PREFIX | REX_R | REX_W) 524 #define REX_BW (REX_PREFIX | REX_B | REX_W) 525 #define REX_BRW (REX_PREFIX | REX_B | REX_R | REX_W) 526 527 #define REG_ESP 0x4 528 529 #define INSN_ADDMR 0x03 /* addq mem,reg */ 530 #define INSN_ADDIR 0x81 /* addq imm,reg */ 531 #define INSN_MOVMR 0x8b /* movq mem,reg */ 532 #define INSN_MOVIR 0xc7 /* movq imm,reg */ 533 #define INSN_LEA 0x8d /* leaq mem,reg */ 534 535 static Fixupret 536 tls_fixups(Ofl_desc *ofl, Rel_desc *arsp) 537 { 538 Sym_desc *sdp = arsp->rel_sym; 539 Word rtype = arsp->rel_rtype; 540 uchar_t *offset; 541 542 offset = (uchar_t *)((uintptr_t)arsp->rel_roffset + 543 (uintptr_t)_elf_getxoff(arsp->rel_isdesc->is_indata) + 544 (uintptr_t)RELAUX_GET_OSDESC(arsp)->os_outdata->d_buf); 545 546 /* 547 * Note that in certain of the original insn sequences below, the 548 * instructions are not necessarily adjacent 549 */ 550 if (sdp->sd_ref == REF_DYN_NEED) { 551 /* 552 * IE reference model 553 */ 554 switch (rtype) { 555 case R_AMD64_TLSGD: 556 /* 557 * GD -> IE 558 * 559 * Transition: 560 * 0x00 .byte 0x66 561 * 0x01 leaq x@tlsgd(%rip), %rdi 562 * 0x08 .word 0x6666 563 * 0x0a rex64 564 * 0x0b call __tls_get_addr@plt 565 * 0x10 566 * To: 567 * 0x00 movq %fs:0, %rax 568 * 0x09 addq x@gottpoff(%rip), %rax 569 * 0x10 570 */ 571 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 572 R_AMD64_GOTTPOFF, arsp, ld_reloc_sym_name)); 573 arsp->rel_rtype = R_AMD64_GOTTPOFF; 574 arsp->rel_roffset += 8; 575 arsp->rel_raddend = (Sxword)-4; 576 577 /* 578 * Adjust 'offset' to beginning of instruction 579 * sequence. 580 */ 581 offset -= 4; 582 (void) memcpy(offset, tlsinstr_gd_ie, 583 sizeof (tlsinstr_gd_ie)); 584 return (FIX_RELOC); 585 586 case R_AMD64_PLT32: 587 /* 588 * Fixup done via the TLS_GD relocation. 589 */ 590 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 591 R_AMD64_NONE, arsp, ld_reloc_sym_name)); 592 return (FIX_DONE); 593 } 594 } 595 596 /* 597 * LE reference model 598 */ 599 switch (rtype) { 600 case R_AMD64_TLSGD: 601 /* 602 * GD -> LE 603 * 604 * Transition: 605 * 0x00 .byte 0x66 606 * 0x01 leaq x@tlsgd(%rip), %rdi 607 * 0x08 .word 0x6666 608 * 0x0a rex64 609 * 0x0b call __tls_get_addr@plt 610 * 0x10 611 * To: 612 * 0x00 movq %fs:0, %rax 613 * 0x09 leaq x@tpoff(%rax), %rax 614 * 0x10 615 */ 616 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 617 R_AMD64_TPOFF32, arsp, ld_reloc_sym_name)); 618 arsp->rel_rtype = R_AMD64_TPOFF32; 619 arsp->rel_roffset += 8; 620 arsp->rel_raddend = 0; 621 622 /* 623 * Adjust 'offset' to beginning of instruction sequence. 624 */ 625 offset -= 4; 626 (void) memcpy(offset, tlsinstr_gd_le, sizeof (tlsinstr_gd_le)); 627 return (FIX_RELOC); 628 629 case R_AMD64_GOTTPOFF: { 630 /* 631 * IE -> LE 632 * 633 * Transition 1: 634 * movq %fs:0, %reg 635 * addq x@gottpoff(%rip), %reg 636 * To: 637 * movq %fs:0, %reg 638 * leaq x@tpoff(%reg), %reg 639 * 640 * Transition (as a special case): 641 * movq %fs:0, %r12/%rsp 642 * addq x@gottpoff(%rip), %r12/%rsp 643 * To: 644 * movq %fs:0, %r12/%rsp 645 * addq x@tpoff(%rax), %r12/%rsp 646 * 647 * Transition 2: 648 * movq x@gottpoff(%rip), %reg 649 * movq %fs:(%reg), %reg 650 * To: 651 * movq x@tpoff(%reg), %reg 652 * movq %fs:(%reg), %reg 653 */ 654 Conv_inv_buf_t inv_buf; 655 uint8_t reg; /* Register */ 656 657 offset -= 3; 658 659 reg = offset[2] >> 3; /* Encoded dest. reg. operand */ 660 661 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 662 R_AMD64_TPOFF32, arsp, ld_reloc_sym_name)); 663 arsp->rel_rtype = R_AMD64_TPOFF32; 664 arsp->rel_raddend = 0; 665 666 /* 667 * This is transition 2, and the special case of form 1 where 668 * a normal transition would index %rsp or %r12 and need a SIB 669 * byte in the leaq for which we lack space 670 */ 671 if ((offset[1] == INSN_MOVMR) || 672 ((offset[1] == INSN_ADDMR) && (reg == REG_ESP))) { 673 /* 674 * If we needed an extra bit of MOD.reg to refer to 675 * this register as the dest of the original movq we 676 * need an extra bit of MOD.rm to refer to it in the 677 * dest of the replacement movq or addq. 678 */ 679 if (offset[0] == REX_RW) 680 offset[0] = REX_BW; 681 682 offset[1] = (offset[1] == INSN_MOVMR) ? 683 INSN_MOVIR : INSN_ADDIR; 684 offset[2] = 0xc0 | reg; 685 686 return (FIX_RELOC); 687 } else if (offset[1] == INSN_ADDMR) { 688 /* 689 * If we needed an extra bit of MOD.reg to refer to 690 * this register in the dest of the addq we need an 691 * extra bit of both MOD.reg and MOD.rm to refer to it 692 * in the source and dest of the leaq 693 */ 694 if (offset[0] == REX_RW) 695 offset[0] = REX_BRW; 696 697 offset[1] = INSN_LEA; 698 offset[2] = 0x80 | (reg << 3) | reg; 699 700 return (FIX_RELOC); 701 } 702 703 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_REL_BADTLSINS), 704 conv_reloc_amd64_type(arsp->rel_rtype, 0, &inv_buf), 705 arsp->rel_isdesc->is_file->ifl_name, 706 ld_reloc_sym_name(arsp), 707 arsp->rel_isdesc->is_name, 708 EC_OFF(arsp->rel_roffset)); 709 return (FIX_ERROR); 710 } 711 case R_AMD64_TLSLD: 712 /* 713 * LD -> LE 714 * 715 * Transition 716 * 0x00 leaq x1@tlsgd(%rip), %rdi 717 * 0x07 call __tls_get_addr@plt 718 * 0x0c 719 * To: 720 * 0x00 .byte 0x66 721 * 0x01 .byte 0x66 722 * 0x02 .byte 0x66 723 * 0x03 movq %fs:0, %rax 724 */ 725 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 726 R_AMD64_NONE, arsp, ld_reloc_sym_name)); 727 offset -= 3; 728 (void) memcpy(offset, tlsinstr_ld_le, sizeof (tlsinstr_ld_le)); 729 return (FIX_DONE); 730 731 case R_AMD64_DTPOFF32: 732 /* 733 * LD->LE 734 * 735 * Transition: 736 * 0x00 leaq x1@dtpoff(%rax), %rcx 737 * To: 738 * 0x00 leaq x1@tpoff(%rax), %rcx 739 */ 740 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 741 R_AMD64_TPOFF32, arsp, ld_reloc_sym_name)); 742 arsp->rel_rtype = R_AMD64_TPOFF32; 743 arsp->rel_raddend = 0; 744 return (FIX_RELOC); 745 } 746 747 return (FIX_RELOC); 748 } 749 750 static uintptr_t 751 ld_do_activerelocs(Ofl_desc *ofl) 752 { 753 Rel_desc *arsp; 754 Rel_cachebuf *rcbp; 755 Aliste idx; 756 uintptr_t return_code = 1; 757 ofl_flag_t flags = ofl->ofl_flags; 758 759 if (aplist_nitems(ofl->ofl_actrels.rc_list) != 0) 760 DBG_CALL(Dbg_reloc_doact_title(ofl->ofl_lml)); 761 762 /* 763 * Process active relocations. 764 */ 765 REL_CACHE_TRAVERSE(&ofl->ofl_actrels, idx, rcbp, arsp) { 766 uchar_t *addr; 767 Xword value; 768 Sym_desc *sdp; 769 const char *ifl_name; 770 Xword refaddr; 771 int moved = 0; 772 Gotref gref; 773 Os_desc *osp; 774 775 /* 776 * If the section this relocation is against has been discarded 777 * (-zignore), then discard (skip) the relocation itself. 778 */ 779 if ((arsp->rel_isdesc->is_flags & FLG_IS_DISCARD) && 780 ((arsp->rel_flags & (FLG_REL_GOT | FLG_REL_BSS | 781 FLG_REL_PLT | FLG_REL_NOINFO)) == 0)) { 782 DBG_CALL(Dbg_reloc_discard(ofl->ofl_lml, M_MACH, arsp)); 783 continue; 784 } 785 786 /* 787 * We determine what the 'got reference' model (if required) 788 * is at this point. This needs to be done before tls_fixup() 789 * since it may 'transition' our instructions. 790 * 791 * The got table entries have already been assigned, 792 * and we bind to those initial entries. 793 */ 794 if (arsp->rel_flags & FLG_REL_DTLS) 795 gref = GOT_REF_TLSGD; 796 else if (arsp->rel_flags & FLG_REL_MTLS) 797 gref = GOT_REF_TLSLD; 798 else if (arsp->rel_flags & FLG_REL_STLS) 799 gref = GOT_REF_TLSIE; 800 else 801 gref = GOT_REF_GENERIC; 802 803 /* 804 * Perform any required TLS fixups. 805 */ 806 if (arsp->rel_flags & FLG_REL_TLSFIX) { 807 Fixupret ret; 808 809 if ((ret = tls_fixups(ofl, arsp)) == FIX_ERROR) 810 return (S_ERROR); 811 if (ret == FIX_DONE) 812 continue; 813 } 814 815 /* 816 * If this is a relocation against a move table, or 817 * expanded move table, adjust the relocation entries. 818 */ 819 if (RELAUX_GET_MOVE(arsp)) 820 ld_adj_movereloc(ofl, arsp); 821 822 sdp = arsp->rel_sym; 823 refaddr = arsp->rel_roffset + 824 (Off)_elf_getxoff(arsp->rel_isdesc->is_indata); 825 826 if ((arsp->rel_flags & FLG_REL_CLVAL) || 827 (arsp->rel_flags & FLG_REL_GOTCL)) 828 value = 0; 829 else if (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) { 830 Sym_desc *sym; 831 832 /* 833 * The value for a symbol pointing to a SECTION 834 * is based off of that sections position. 835 */ 836 if ((sdp->sd_isc->is_flags & FLG_IS_RELUPD) && 837 /* LINTED */ 838 (sym = ld_am_I_partial(arsp, arsp->rel_raddend))) { 839 /* 840 * The symbol was moved, so adjust the value 841 * relative to the new section. 842 */ 843 value = sym->sd_sym->st_value; 844 moved = 1; 845 846 /* 847 * The original raddend covers the displacement 848 * from the section start to the desired 849 * address. The value computed above gets us 850 * from the section start to the start of the 851 * symbol range. Adjust the old raddend to 852 * remove the offset from section start to 853 * symbol start, leaving the displacement 854 * within the range of the symbol. 855 */ 856 arsp->rel_raddend -= sym->sd_osym->st_value; 857 } else { 858 value = _elf_getxoff(sdp->sd_isc->is_indata); 859 if (sdp->sd_isc->is_shdr->sh_flags & SHF_ALLOC) 860 value += sdp->sd_isc->is_osdesc-> 861 os_shdr->sh_addr; 862 } 863 if (sdp->sd_isc->is_shdr->sh_flags & SHF_TLS) 864 value -= ofl->ofl_tlsphdr->p_vaddr; 865 866 } else if (IS_SIZE(arsp->rel_rtype)) { 867 /* 868 * Size relocations require the symbols size. 869 */ 870 value = sdp->sd_sym->st_size; 871 872 } else if ((sdp->sd_flags & FLG_SY_CAP) && 873 sdp->sd_aux && sdp->sd_aux->sa_PLTndx) { 874 /* 875 * If relocation is against a capabilities symbol, we 876 * need to jump to an associated PLT, so that at runtime 877 * ld.so.1 is involved to determine the best binding 878 * choice. Otherwise, the value is the symbols value. 879 */ 880 value = ld_calc_plt_addr(sdp, ofl); 881 } else 882 value = sdp->sd_sym->st_value; 883 884 /* 885 * Relocation against the GLOBAL_OFFSET_TABLE. 886 */ 887 if ((arsp->rel_flags & FLG_REL_GOT) && 888 !ld_reloc_set_aux_osdesc(ofl, arsp, ofl->ofl_osgot)) 889 return (S_ERROR); 890 osp = RELAUX_GET_OSDESC(arsp); 891 892 /* 893 * If loadable and not producing a relocatable object add the 894 * sections virtual address to the reference address. 895 */ 896 if ((arsp->rel_flags & FLG_REL_LOAD) && 897 ((flags & FLG_OF_RELOBJ) == 0)) 898 refaddr += arsp->rel_isdesc->is_osdesc-> 899 os_shdr->sh_addr; 900 901 /* 902 * If this entry has a PLT assigned to it, its value is actually 903 * the address of the PLT (and not the address of the function). 904 */ 905 if (IS_PLT(arsp->rel_rtype)) { 906 if (sdp->sd_aux && sdp->sd_aux->sa_PLTndx) 907 value = ld_calc_plt_addr(sdp, ofl); 908 } 909 910 /* 911 * Add relocations addend to value. Add extra 912 * relocation addend if needed. 913 * 914 * Note: For GOT relative relocations on amd64 we discard the 915 * addend. It was relevant to the reference - not to the 916 * data item being referenced (ie: that -4 thing). 917 */ 918 if ((arsp->rel_flags & FLG_REL_GOT) == 0) 919 value += arsp->rel_raddend; 920 921 /* 922 * Determine whether the value needs further adjustment. Filter 923 * through the attributes of the relocation to determine what 924 * adjustment is required. Note, many of the following cases 925 * are only applicable when a .got is present. As a .got is 926 * not generated when a relocatable object is being built, 927 * any adjustments that require a .got need to be skipped. 928 */ 929 if ((arsp->rel_flags & FLG_REL_GOT) && 930 ((flags & FLG_OF_RELOBJ) == 0)) { 931 Xword R1addr; 932 uintptr_t R2addr; 933 Word gotndx; 934 Gotndx *gnp; 935 936 /* 937 * Perform relocation against GOT table. Since this 938 * doesn't fit exactly into a relocation we place the 939 * appropriate byte in the GOT directly 940 * 941 * Calculate offset into GOT at which to apply 942 * the relocation. 943 */ 944 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, arsp); 945 assert(gnp); 946 947 if (arsp->rel_rtype == R_AMD64_DTPOFF64) 948 gotndx = gnp->gn_gotndx + 1; 949 else 950 gotndx = gnp->gn_gotndx; 951 952 R1addr = (Xword)(gotndx * M_GOT_ENTSIZE); 953 954 /* 955 * Add the GOTs data's offset. 956 */ 957 R2addr = R1addr + (uintptr_t)osp->os_outdata->d_buf; 958 959 DBG_CALL(Dbg_reloc_doact(ofl->ofl_lml, ELF_DBG_LD_ACT, 960 M_MACH, SHT_RELA, arsp, R1addr, value, 961 ld_reloc_sym_name)); 962 963 /* 964 * And do it. 965 */ 966 if (ofl->ofl_flags1 & FLG_OF1_ENCDIFF) 967 *(Xword *)R2addr = ld_bswap_Xword(value); 968 else 969 *(Xword *)R2addr = value; 970 continue; 971 972 } else if (IS_GOT_BASED(arsp->rel_rtype) && 973 ((flags & FLG_OF_RELOBJ) == 0)) { 974 value -= ofl->ofl_osgot->os_shdr->sh_addr; 975 976 } else if (IS_GOTPCREL(arsp->rel_rtype) && 977 ((flags & FLG_OF_RELOBJ) == 0)) { 978 Gotndx *gnp; 979 980 /* 981 * Calculation: 982 * G + GOT + A - P 983 */ 984 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, arsp); 985 assert(gnp); 986 value = (Xword)(ofl->ofl_osgot->os_shdr-> sh_addr) + 987 ((Xword)gnp->gn_gotndx * M_GOT_ENTSIZE) + 988 arsp->rel_raddend - refaddr; 989 990 } else if (IS_GOT_PC(arsp->rel_rtype) && 991 ((flags & FLG_OF_RELOBJ) == 0)) { 992 value = (Xword)(ofl->ofl_osgot->os_shdr-> 993 sh_addr) - refaddr + arsp->rel_raddend; 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, arsp); 1006 assert(gnp); 1007 value = (Xword)gnp->gn_gotndx * M_GOT_ENTSIZE; 1008 1009 } else if (IS_GOT_RELATIVE(arsp->rel_rtype) && 1010 ((flags & FLG_OF_RELOBJ) == 0)) { 1011 Gotndx *gnp; 1012 1013 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, arsp); 1014 assert(gnp); 1015 value = (Xword)gnp->gn_gotndx * M_GOT_ENTSIZE; 1016 1017 } else if ((arsp->rel_flags & FLG_REL_STLS) && 1018 ((flags & FLG_OF_RELOBJ) == 0)) { 1019 Xword tlsstatsize; 1020 1021 /* 1022 * This is the LE TLS reference model. Static 1023 * offset is hard-coded. 1024 */ 1025 tlsstatsize = S_ROUND(ofl->ofl_tlsphdr->p_memsz, 1026 M_TLSSTATALIGN); 1027 value = tlsstatsize - value; 1028 1029 /* 1030 * Since this code is fixed up, it assumes a negative 1031 * offset that can be added to the thread pointer. 1032 */ 1033 if (arsp->rel_rtype == R_AMD64_TPOFF32) 1034 value = -value; 1035 } 1036 1037 if (arsp->rel_isdesc->is_file) 1038 ifl_name = arsp->rel_isdesc->is_file->ifl_name; 1039 else 1040 ifl_name = MSG_INTL(MSG_STR_NULL); 1041 1042 /* 1043 * Make sure we have data to relocate. Compiler and assembler 1044 * developers have been known to generate relocations against 1045 * invalid sections (normally .bss), so for their benefit give 1046 * them sufficient information to help analyze the problem. 1047 * End users should never see this. 1048 */ 1049 if (arsp->rel_isdesc->is_indata->d_buf == 0) { 1050 Conv_inv_buf_t inv_buf; 1051 1052 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_REL_EMPTYSEC), 1053 conv_reloc_amd64_type(arsp->rel_rtype, 0, &inv_buf), 1054 ifl_name, ld_reloc_sym_name(arsp), 1055 EC_WORD(arsp->rel_isdesc->is_scnndx), 1056 arsp->rel_isdesc->is_name); 1057 return (S_ERROR); 1058 } 1059 1060 /* 1061 * Get the address of the data item we need to modify. 1062 */ 1063 addr = (uchar_t *)((uintptr_t)arsp->rel_roffset + 1064 (uintptr_t)_elf_getxoff(arsp->rel_isdesc->is_indata)); 1065 1066 DBG_CALL(Dbg_reloc_doact(ofl->ofl_lml, ELF_DBG_LD_ACT, 1067 M_MACH, SHT_RELA, arsp, EC_NATPTR(addr), value, 1068 ld_reloc_sym_name)); 1069 addr += (uintptr_t)osp->os_outdata->d_buf; 1070 1071 if ((((uintptr_t)addr - (uintptr_t)ofl->ofl_nehdr) > 1072 ofl->ofl_size) || (arsp->rel_roffset > 1073 osp->os_shdr->sh_size)) { 1074 int class; 1075 Conv_inv_buf_t inv_buf; 1076 1077 if (((uintptr_t)addr - (uintptr_t)ofl->ofl_nehdr) > 1078 ofl->ofl_size) 1079 class = ERR_FATAL; 1080 else 1081 class = ERR_WARNING; 1082 1083 ld_eprintf(ofl, class, MSG_INTL(MSG_REL_INVALOFFSET), 1084 conv_reloc_amd64_type(arsp->rel_rtype, 0, &inv_buf), 1085 ifl_name, EC_WORD(arsp->rel_isdesc->is_scnndx), 1086 arsp->rel_isdesc->is_name, ld_reloc_sym_name(arsp), 1087 EC_ADDR((uintptr_t)addr - 1088 (uintptr_t)ofl->ofl_nehdr)); 1089 1090 if (class == ERR_FATAL) { 1091 return_code = S_ERROR; 1092 continue; 1093 } 1094 } 1095 1096 /* 1097 * The relocation is additive. Ignore the previous symbol 1098 * value if this local partial symbol is expanded. 1099 */ 1100 if (moved) 1101 value -= *addr; 1102 1103 /* 1104 * If '-z noreloc' is specified - skip the do_reloc_ld stage. 1105 */ 1106 if (OFL_DO_RELOC(ofl)) { 1107 /* 1108 * If this is a PROGBITS section and the running linker 1109 * has a different byte order than the target host, 1110 * tell do_reloc_ld() to swap bytes. 1111 */ 1112 if (do_reloc_ld(arsp, addr, &value, ld_reloc_sym_name, 1113 ifl_name, OFL_SWAP_RELOC_DATA(ofl, arsp), 1114 ofl->ofl_lml) == 0) { 1115 ofl->ofl_flags |= FLG_OF_FATAL; 1116 return_code = S_ERROR; 1117 } 1118 } 1119 } 1120 return (return_code); 1121 } 1122 1123 static uintptr_t 1124 ld_add_outrel(Word flags, Rel_desc *rsp, Ofl_desc *ofl) 1125 { 1126 Rel_desc *orsp; 1127 Sym_desc *sdp = rsp->rel_sym; 1128 1129 /* 1130 * Static executables *do not* want any relocations against them. 1131 * Since our engine still creates relocations against a WEAK UNDEFINED 1132 * symbol in a static executable, it's best to disable them here 1133 * instead of through out the relocation code. 1134 */ 1135 if (OFL_IS_STATIC_EXEC(ofl)) 1136 return (1); 1137 1138 /* 1139 * If we are adding a output relocation against a section 1140 * symbol (non-RELATIVE) then mark that section. These sections 1141 * will be added to the .dynsym symbol table. 1142 */ 1143 if (sdp && (rsp->rel_rtype != M_R_RELATIVE) && 1144 ((flags & FLG_REL_SCNNDX) || 1145 (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION))) { 1146 1147 /* 1148 * If this is a COMMON symbol - no output section 1149 * exists yet - (it's created as part of sym_validate()). 1150 * So - we mark here that when it's created it should 1151 * be tagged with the FLG_OS_OUTREL flag. 1152 */ 1153 if ((sdp->sd_flags & FLG_SY_SPECSEC) && 1154 (sdp->sd_sym->st_shndx == SHN_COMMON)) { 1155 if (ELF_ST_TYPE(sdp->sd_sym->st_info) != STT_TLS) 1156 ofl->ofl_flags1 |= FLG_OF1_BSSOREL; 1157 else 1158 ofl->ofl_flags1 |= FLG_OF1_TLSOREL; 1159 } else { 1160 Os_desc *osp; 1161 Is_desc *isp = sdp->sd_isc; 1162 1163 if (isp && ((osp = isp->is_osdesc) != NULL) && 1164 ((osp->os_flags & FLG_OS_OUTREL) == 0)) { 1165 ofl->ofl_dynshdrcnt++; 1166 osp->os_flags |= FLG_OS_OUTREL; 1167 } 1168 } 1169 } 1170 1171 /* Enter it into the output relocation cache */ 1172 if ((orsp = ld_reloc_enter(ofl, &ofl->ofl_outrels, rsp, flags)) == NULL) 1173 return (S_ERROR); 1174 1175 if (flags & FLG_REL_GOT) 1176 ofl->ofl_relocgotsz += (Xword)sizeof (Rela); 1177 else if (flags & FLG_REL_PLT) 1178 ofl->ofl_relocpltsz += (Xword)sizeof (Rela); 1179 else if (flags & FLG_REL_BSS) 1180 ofl->ofl_relocbsssz += (Xword)sizeof (Rela); 1181 else if (flags & FLG_REL_NOINFO) 1182 ofl->ofl_relocrelsz += (Xword)sizeof (Rela); 1183 else 1184 RELAUX_GET_OSDESC(orsp)->os_szoutrels += (Xword)sizeof (Rela); 1185 1186 if (orsp->rel_rtype == M_R_RELATIVE) 1187 ofl->ofl_relocrelcnt++; 1188 1189 /* 1190 * We don't perform sorting on PLT relocations because 1191 * they have already been assigned a PLT index and if we 1192 * were to sort them we would have to re-assign the plt indexes. 1193 */ 1194 if (!(flags & FLG_REL_PLT)) 1195 ofl->ofl_reloccnt++; 1196 1197 /* 1198 * Insure a GLOBAL_OFFSET_TABLE is generated if required. 1199 */ 1200 if (IS_GOT_REQUIRED(orsp->rel_rtype)) 1201 ofl->ofl_flags |= FLG_OF_BLDGOT; 1202 1203 /* 1204 * Identify and possibly warn of a displacement relocation. 1205 */ 1206 if (orsp->rel_flags & FLG_REL_DISP) { 1207 ofl->ofl_dtflags_1 |= DF_1_DISPRELPND; 1208 1209 if (ofl->ofl_flags & FLG_OF_VERBOSE) 1210 ld_disp_errmsg(MSG_INTL(MSG_REL_DISPREL4), orsp, ofl); 1211 } 1212 DBG_CALL(Dbg_reloc_ors_entry(ofl->ofl_lml, ELF_DBG_LD, SHT_RELA, 1213 M_MACH, orsp)); 1214 return (1); 1215 } 1216 1217 /* 1218 * process relocation for a LOCAL symbol 1219 */ 1220 static uintptr_t 1221 ld_reloc_local(Rel_desc * rsp, Ofl_desc * ofl) 1222 { 1223 ofl_flag_t flags = ofl->ofl_flags; 1224 Sym_desc *sdp = rsp->rel_sym; 1225 Word shndx = sdp->sd_sym->st_shndx; 1226 Word ortype = rsp->rel_rtype; 1227 1228 /* 1229 * if ((shared object) and (not pc relative relocation) and 1230 * (not against ABS symbol)) 1231 * then 1232 * build R_AMD64_RELATIVE 1233 * fi 1234 */ 1235 if ((flags & FLG_OF_SHAROBJ) && (rsp->rel_flags & FLG_REL_LOAD) && 1236 !(IS_PC_RELATIVE(rsp->rel_rtype)) && !(IS_SIZE(rsp->rel_rtype)) && 1237 !(IS_GOT_BASED(rsp->rel_rtype)) && 1238 !(rsp->rel_isdesc != NULL && 1239 (rsp->rel_isdesc->is_shdr->sh_type == SHT_SUNW_dof)) && 1240 (((sdp->sd_flags & FLG_SY_SPECSEC) == 0) || 1241 (shndx != SHN_ABS) || (sdp->sd_aux && sdp->sd_aux->sa_symspec))) { 1242 1243 /* 1244 * R_AMD64_RELATIVE updates a 64bit address, if this 1245 * relocation isn't a 64bit binding then we can not 1246 * simplify it to a RELATIVE relocation. 1247 */ 1248 if (reloc_table[ortype].re_fsize != sizeof (Addr)) { 1249 return (ld_add_outrel(0, rsp, ofl)); 1250 } 1251 1252 rsp->rel_rtype = R_AMD64_RELATIVE; 1253 if (ld_add_outrel(FLG_REL_ADVAL, rsp, ofl) == S_ERROR) 1254 return (S_ERROR); 1255 rsp->rel_rtype = ortype; 1256 return (1); 1257 } 1258 1259 /* 1260 * If the relocation is against a 'non-allocatable' section 1261 * and we can not resolve it now - then give a warning 1262 * message. 1263 * 1264 * We can not resolve the symbol if either: 1265 * a) it's undefined 1266 * b) it's defined in a shared library and a 1267 * COPY relocation hasn't moved it to the executable 1268 * 1269 * Note: because we process all of the relocations against the 1270 * text segment before any others - we know whether 1271 * or not a copy relocation will be generated before 1272 * we get here (see reloc_init()->reloc_segments()). 1273 */ 1274 if (!(rsp->rel_flags & FLG_REL_LOAD) && 1275 ((shndx == SHN_UNDEF) || 1276 ((sdp->sd_ref == REF_DYN_NEED) && 1277 ((sdp->sd_flags & FLG_SY_MVTOCOMM) == 0)))) { 1278 Conv_inv_buf_t inv_buf; 1279 Os_desc *osp = RELAUX_GET_OSDESC(rsp); 1280 1281 /* 1282 * If the relocation is against a SHT_SUNW_ANNOTATE 1283 * section - then silently ignore that the relocation 1284 * can not be resolved. 1285 */ 1286 if (osp && (osp->os_shdr->sh_type == SHT_SUNW_ANNOTATE)) 1287 return (0); 1288 ld_eprintf(ofl, ERR_WARNING, MSG_INTL(MSG_REL_EXTERNSYM), 1289 conv_reloc_amd64_type(rsp->rel_rtype, 0, &inv_buf), 1290 rsp->rel_isdesc->is_file->ifl_name, 1291 ld_reloc_sym_name(rsp), osp->os_name); 1292 return (1); 1293 } 1294 1295 /* 1296 * Perform relocation. 1297 */ 1298 return (ld_add_actrel(NULL, rsp, ofl)); 1299 } 1300 1301 1302 static uintptr_t 1303 ld_reloc_TLS(Boolean local, Rel_desc * rsp, Ofl_desc * ofl) 1304 { 1305 Word rtype = rsp->rel_rtype; 1306 Sym_desc *sdp = rsp->rel_sym; 1307 ofl_flag_t flags = ofl->ofl_flags; 1308 Gotndx *gnp; 1309 1310 /* 1311 * If we're building an executable - use either the IE or LE access 1312 * model. If we're building a shared object process any IE model. 1313 */ 1314 if ((flags & FLG_OF_EXEC) || (IS_TLS_IE(rtype))) { 1315 /* 1316 * Set the DF_STATIC_TLS flag. 1317 */ 1318 ofl->ofl_dtflags |= DF_STATIC_TLS; 1319 1320 if (!local || ((flags & FLG_OF_EXEC) == 0)) { 1321 /* 1322 * Assign a GOT entry for static TLS references. 1323 */ 1324 if ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs, 1325 GOT_REF_TLSIE, ofl, rsp)) == NULL) { 1326 1327 if (ld_assign_got_TLS(local, rsp, ofl, sdp, 1328 gnp, GOT_REF_TLSIE, FLG_REL_STLS, 1329 rtype, R_AMD64_TPOFF64, 0) == S_ERROR) 1330 return (S_ERROR); 1331 } 1332 1333 /* 1334 * IE access model. 1335 */ 1336 if (IS_TLS_IE(rtype)) 1337 return (ld_add_actrel(FLG_REL_STLS, rsp, ofl)); 1338 1339 /* 1340 * Fixups are required for other executable models. 1341 */ 1342 return (ld_add_actrel((FLG_REL_TLSFIX | FLG_REL_STLS), 1343 rsp, ofl)); 1344 } 1345 1346 /* 1347 * LE access model. 1348 */ 1349 if (IS_TLS_LE(rtype)) 1350 return (ld_add_actrel(FLG_REL_STLS, rsp, ofl)); 1351 1352 return (ld_add_actrel((FLG_REL_TLSFIX | FLG_REL_STLS), 1353 rsp, ofl)); 1354 } 1355 1356 /* 1357 * Building a shared object. 1358 * 1359 * Assign a GOT entry for a dynamic TLS reference. 1360 */ 1361 if (IS_TLS_LD(rtype) && ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs, 1362 GOT_REF_TLSLD, ofl, rsp)) == NULL)) { 1363 1364 if (ld_assign_got_TLS(local, rsp, ofl, sdp, gnp, GOT_REF_TLSLD, 1365 FLG_REL_MTLS, rtype, R_AMD64_DTPMOD64, NULL) == S_ERROR) 1366 return (S_ERROR); 1367 1368 } else if (IS_TLS_GD(rtype) && 1369 ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs, GOT_REF_TLSGD, 1370 ofl, rsp)) == NULL)) { 1371 1372 if (ld_assign_got_TLS(local, rsp, ofl, sdp, gnp, GOT_REF_TLSGD, 1373 FLG_REL_DTLS, rtype, R_AMD64_DTPMOD64, 1374 R_AMD64_DTPOFF64) == S_ERROR) 1375 return (S_ERROR); 1376 } 1377 1378 if (IS_TLS_LD(rtype)) 1379 return (ld_add_actrel(FLG_REL_MTLS, rsp, ofl)); 1380 1381 return (ld_add_actrel(FLG_REL_DTLS, rsp, ofl)); 1382 } 1383 1384 /* ARGSUSED5 */ 1385 static uintptr_t 1386 ld_assign_got_ndx(Alist **alpp, Gotndx *pgnp, Gotref gref, Ofl_desc *ofl, 1387 Rel_desc *rsp, Sym_desc *sdp) 1388 { 1389 Xword raddend; 1390 Gotndx gn, *gnp; 1391 Aliste idx; 1392 uint_t gotents; 1393 1394 raddend = rsp->rel_raddend; 1395 if (pgnp && (pgnp->gn_addend == raddend) && (pgnp->gn_gotref == gref)) 1396 return (1); 1397 1398 if ((gref == GOT_REF_TLSGD) || (gref == GOT_REF_TLSLD)) 1399 gotents = 2; 1400 else 1401 gotents = 1; 1402 1403 gn.gn_addend = raddend; 1404 gn.gn_gotndx = ofl->ofl_gotcnt; 1405 gn.gn_gotref = gref; 1406 1407 ofl->ofl_gotcnt += gotents; 1408 1409 if (gref == GOT_REF_TLSLD) { 1410 if (ofl->ofl_tlsldgotndx == NULL) { 1411 if ((gnp = libld_malloc(sizeof (Gotndx))) == NULL) 1412 return (S_ERROR); 1413 (void) memcpy(gnp, &gn, sizeof (Gotndx)); 1414 ofl->ofl_tlsldgotndx = gnp; 1415 } 1416 return (1); 1417 } 1418 1419 idx = 0; 1420 for (ALIST_TRAVERSE(*alpp, idx, gnp)) { 1421 if (gnp->gn_addend > raddend) 1422 break; 1423 } 1424 1425 /* 1426 * GOT indexes are maintained on an Alist, where there is typically 1427 * only one index. The usage of this list is to scan the list to find 1428 * an index, and then apply that index immediately to a relocation. 1429 * Thus there are no external references to these GOT index structures 1430 * that can be compromised by the Alist being reallocated. 1431 */ 1432 if (alist_insert(alpp, &gn, sizeof (Gotndx), 1433 AL_CNT_SDP_GOT, idx) == NULL) 1434 return (S_ERROR); 1435 1436 return (1); 1437 } 1438 1439 static void 1440 ld_assign_plt_ndx(Sym_desc * sdp, Ofl_desc *ofl) 1441 { 1442 sdp->sd_aux->sa_PLTndx = 1 + ofl->ofl_pltcnt++; 1443 sdp->sd_aux->sa_PLTGOTndx = ofl->ofl_gotcnt++; 1444 ofl->ofl_flags |= FLG_OF_BLDGOT; 1445 } 1446 1447 static uchar_t plt0_template[M_PLT_ENTSIZE] = { 1448 /* 0x00 PUSHQ GOT+8(%rip) */ 0xff, 0x35, 0x00, 0x00, 0x00, 0x00, 1449 /* 0x06 JMP *GOT+16(%rip) */ 0xff, 0x25, 0x00, 0x00, 0x00, 0x00, 1450 /* 0x0c NOP */ 0x90, 1451 /* 0x0d NOP */ 0x90, 1452 /* 0x0e NOP */ 0x90, 1453 /* 0x0f NOP */ 0x90 1454 }; 1455 1456 /* 1457 * Initializes .got[0] with the _DYNAMIC symbol value. 1458 */ 1459 static uintptr_t 1460 ld_fillin_gotplt(Ofl_desc *ofl) 1461 { 1462 int bswap = (ofl->ofl_flags1 & FLG_OF1_ENCDIFF) != 0; 1463 1464 if (ofl->ofl_osgot) { 1465 Sym_desc *sdp; 1466 1467 if ((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_DYNAMIC_U), 1468 SYM_NOHASH, NULL, ofl)) != NULL) { 1469 uchar_t *genptr; 1470 1471 genptr = ((uchar_t *)ofl->ofl_osgot->os_outdata->d_buf + 1472 (M_GOT_XDYNAMIC * M_GOT_ENTSIZE)); 1473 /* LINTED */ 1474 *(Xword *)genptr = sdp->sd_sym->st_value; 1475 if (bswap) 1476 /* LINTED */ 1477 *(Xword *)genptr = 1478 /* LINTED */ 1479 ld_bswap_Xword(*(Xword *)genptr); 1480 } 1481 } 1482 1483 /* 1484 * Fill in the reserved slot in the procedure linkage table the first 1485 * entry is: 1486 * 0x00 PUSHQ GOT+8(%rip) # GOT[1] 1487 * 0x06 JMP *GOT+16(%rip) # GOT[2] 1488 * 0x0c NOP 1489 * 0x0d NOP 1490 * 0x0e NOP 1491 * 0x0f NOP 1492 */ 1493 if ((ofl->ofl_flags & FLG_OF_DYNAMIC) && ofl->ofl_osplt) { 1494 uchar_t *pltent; 1495 Xword val1; 1496 1497 pltent = (uchar_t *)ofl->ofl_osplt->os_outdata->d_buf; 1498 bcopy(plt0_template, pltent, sizeof (plt0_template)); 1499 1500 /* 1501 * If '-z noreloc' is specified - skip the do_reloc_ld 1502 * stage. 1503 */ 1504 if (!OFL_DO_RELOC(ofl)) 1505 return (1); 1506 1507 /* 1508 * filin: 1509 * PUSHQ GOT + 8(%rip) 1510 * 1511 * Note: 0x06 below represents the offset to the 1512 * next instruction - which is what %rip will 1513 * be pointing at. 1514 */ 1515 val1 = (ofl->ofl_osgot->os_shdr->sh_addr) + 1516 (M_GOT_XLINKMAP * M_GOT_ENTSIZE) - 1517 ofl->ofl_osplt->os_shdr->sh_addr - 0x06; 1518 1519 if (do_reloc_ld(&rdesc_r_amd64_gotpcrel, &pltent[0x02], 1520 &val1, syn_rdesc_sym_name, MSG_ORIG(MSG_SPECFIL_PLTENT), 1521 bswap, ofl->ofl_lml) == 0) { 1522 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_PLT_PLT0FAIL)); 1523 return (S_ERROR); 1524 } 1525 1526 /* 1527 * filin: 1528 * JMP *GOT+16(%rip) 1529 */ 1530 val1 = (ofl->ofl_osgot->os_shdr->sh_addr) + 1531 (M_GOT_XRTLD * M_GOT_ENTSIZE) - 1532 ofl->ofl_osplt->os_shdr->sh_addr - 0x0c; 1533 1534 if (do_reloc_ld(&rdesc_r_amd64_gotpcrel, &pltent[0x08], 1535 &val1, syn_rdesc_sym_name, MSG_ORIG(MSG_SPECFIL_PLTENT), 1536 bswap, ofl->ofl_lml) == 0) { 1537 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_PLT_PLT0FAIL)); 1538 return (S_ERROR); 1539 } 1540 } 1541 1542 return (1); 1543 } 1544 1545 1546 1547 /* 1548 * Template for generating "void (*)(void)" function 1549 */ 1550 static const uchar_t nullfunc_tmpl[] = { /* amd64 */ 1551 /* 0x00 */ 0x55, /* pushq %rbp */ 1552 /* 0x01 */ 0x48, 0x8b, 0xec, /* movq %rsp,%rbp */ 1553 /* 0x04 */ 0x48, 0x8b, 0xe5, /* movq %rbp,%rsp */ 1554 /* 0x07 */ 0x5d, /* popq %rbp */ 1555 /* 0x08 */ 0xc3 /* ret */ 1556 }; 1557 1558 1559 /* 1560 * Function used to provide fill padding in SHF_EXECINSTR sections 1561 * 1562 * entry: 1563 * 1564 * base - base address of section being filled 1565 * offset - starting offset for fill within memory referenced by base 1566 * cnt - # bytes to be filled 1567 * 1568 * exit: 1569 * The fill has been completed. 1570 */ 1571 static void 1572 execfill(void *base, off_t off, size_t cnt) 1573 { 1574 /* 1575 * 0x90 is an X86 NOP instruction in both 32 and 64-bit worlds. 1576 * There are no alignment constraints. 1577 */ 1578 (void) memset(off + (char *)base, 0x90, cnt); 1579 } 1580 1581 1582 /* 1583 * Return the ld_targ definition for this target. 1584 */ 1585 const Target * 1586 ld_targ_init_x86(void) 1587 { 1588 static const Target _ld_targ = { 1589 { /* Target_mach */ 1590 M_MACH, /* m_mach */ 1591 M_MACHPLUS, /* m_machplus */ 1592 M_FLAGSPLUS, /* m_flagsplus */ 1593 M_CLASS, /* m_class */ 1594 M_DATA, /* m_data */ 1595 1596 M_SEGM_ALIGN, /* m_segm_align */ 1597 M_SEGM_ORIGIN, /* m_segm_origin */ 1598 M_SEGM_AORIGIN, /* m_segm_aorigin */ 1599 M_DATASEG_PERM, /* m_dataseg_perm */ 1600 M_STACK_PERM, /* m_stack_perm */ 1601 M_WORD_ALIGN, /* m_word_align */ 1602 MSG_ORIG(MSG_PTH_RTLD_AMD64), /* m_def_interp */ 1603 1604 /* Relocation type codes */ 1605 M_R_ARRAYADDR, /* m_r_arrayaddr */ 1606 M_R_COPY, /* m_r_copy */ 1607 M_R_GLOB_DAT, /* m_r_glob_dat */ 1608 M_R_JMP_SLOT, /* m_r_jmp_slot */ 1609 M_R_NUM, /* m_r_num */ 1610 M_R_NONE, /* m_r_none */ 1611 M_R_RELATIVE, /* m_r_relative */ 1612 M_R_REGISTER, /* m_r_register */ 1613 1614 /* Relocation related constants */ 1615 M_REL_DT_COUNT, /* m_rel_dt_count */ 1616 M_REL_DT_ENT, /* m_rel_dt_ent */ 1617 M_REL_DT_SIZE, /* m_rel_dt_size */ 1618 M_REL_DT_TYPE, /* m_rel_dt_type */ 1619 M_REL_SHT_TYPE, /* m_rel_sht_type */ 1620 1621 /* GOT related constants */ 1622 M_GOT_ENTSIZE, /* m_got_entsize */ 1623 M_GOT_XNumber, /* m_got_xnumber */ 1624 1625 /* PLT related constants */ 1626 M_PLT_ALIGN, /* m_plt_align */ 1627 M_PLT_ENTSIZE, /* m_plt_entsize */ 1628 M_PLT_RESERVSZ, /* m_plt_reservsz */ 1629 M_PLT_SHF_FLAGS, /* m_plt_shf_flags */ 1630 1631 /* Section type of .eh_frame/.eh_frame_hdr sections */ 1632 SHT_AMD64_UNWIND, /* m_sht_unwind */ 1633 1634 M_DT_REGISTER, /* m_dt_register */ 1635 }, 1636 { /* Target_machid */ 1637 M_ID_ARRAY, /* id_array */ 1638 M_ID_BSS, /* id_bss */ 1639 M_ID_CAP, /* id_cap */ 1640 M_ID_CAPINFO, /* id_capinfo */ 1641 M_ID_CAPCHAIN, /* id_capchain */ 1642 M_ID_DATA, /* id_data */ 1643 M_ID_DYNAMIC, /* id_dynamic */ 1644 M_ID_DYNSORT, /* id_dynsort */ 1645 M_ID_DYNSTR, /* id_dynstr */ 1646 M_ID_DYNSYM, /* id_dynsym */ 1647 M_ID_DYNSYM_NDX, /* id_dynsym_ndx */ 1648 M_ID_GOT, /* id_got */ 1649 M_ID_UNKNOWN, /* id_gotdata (unused) */ 1650 M_ID_HASH, /* id_hash */ 1651 M_ID_INTERP, /* id_interp */ 1652 M_ID_LBSS, /* id_lbss */ 1653 M_ID_LDYNSYM, /* id_ldynsym */ 1654 M_ID_NOTE, /* id_note */ 1655 M_ID_NULL, /* id_null */ 1656 M_ID_PLT, /* id_plt */ 1657 M_ID_REL, /* id_rel */ 1658 M_ID_STRTAB, /* id_strtab */ 1659 M_ID_SYMINFO, /* id_syminfo */ 1660 M_ID_SYMTAB, /* id_symtab */ 1661 M_ID_SYMTAB_NDX, /* id_symtab_ndx */ 1662 M_ID_TEXT, /* id_text */ 1663 M_ID_TLS, /* id_tls */ 1664 M_ID_TLSBSS, /* id_tlsbss */ 1665 M_ID_UNKNOWN, /* id_unknown */ 1666 M_ID_UNWIND, /* id_unwind */ 1667 M_ID_UNWINDHDR, /* id_unwindhdr */ 1668 M_ID_USER, /* id_user */ 1669 M_ID_VERSION, /* id_version */ 1670 }, 1671 { /* Target_nullfunc */ 1672 nullfunc_tmpl, /* nf_template */ 1673 sizeof (nullfunc_tmpl), /* nf_size */ 1674 }, 1675 { /* Target_fillfunc */ 1676 execfill /* ff_execfill */ 1677 }, 1678 { /* Target_machrel */ 1679 reloc_table, 1680 1681 ld_init_rel, /* mr_init_rel */ 1682 ld_mach_eflags, /* mr_mach_eflags */ 1683 ld_mach_make_dynamic, /* mr_mach_make_dynamic */ 1684 ld_mach_update_odynamic, /* mr_mach_update_odynamic */ 1685 ld_calc_plt_addr, /* mr_calc_plt_addr */ 1686 ld_perform_outreloc, /* mr_perform_outreloc */ 1687 ld_do_activerelocs, /* mr_do_activerelocs */ 1688 ld_add_outrel, /* mr_add_outrel */ 1689 NULL, /* mr_reloc_register */ 1690 ld_reloc_local, /* mr_reloc_local */ 1691 NULL, /* mr_reloc_GOTOP */ 1692 ld_reloc_TLS, /* mr_reloc_TLS */ 1693 NULL, /* mr_assign_got */ 1694 ld_find_got_ndx, /* mr_find_got_ndx */ 1695 ld_calc_got_offset, /* mr_calc_got_offset */ 1696 ld_assign_got_ndx, /* mr_assign_got_ndx */ 1697 ld_assign_plt_ndx, /* mr_assign_plt_ndx */ 1698 NULL, /* mr_allocate_got */ 1699 ld_fillin_gotplt, /* mr_fillin_gotplt */ 1700 }, 1701 { /* Target_machsym */ 1702 NULL, /* ms_reg_check */ 1703 NULL, /* ms_mach_sym_typecheck */ 1704 NULL, /* ms_is_regsym */ 1705 NULL, /* ms_reg_find */ 1706 NULL /* ms_reg_enter */ 1707 } 1708 }; 1709 1710 return (&_ld_targ); 1711 } 1712