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 2009 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* Get the x86 version of the relocation engine */ 28 #define DO_RELOC_LIBLD_X86 29 30 #include <string.h> 31 #include <stdio.h> 32 #include <strings.h> 33 #include <sys/elf_amd64.h> 34 #include <debug.h> 35 #include <reloc.h> 36 #include <i386/machdep_x86.h> 37 #include "msg.h" 38 #include "_libld.h" 39 40 /* 41 * Search the GOT index list for a GOT entry with a matching reference and the 42 * proper addend. 43 */ 44 static Gotndx * 45 ld_find_got_ndx(Alist *alp, Gotref gref, Ofl_desc *ofl, Rel_desc *rdesc) 46 { 47 Aliste idx; 48 Gotndx *gnp; 49 50 assert(rdesc != 0); 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 ((rdesc->rel_raddend == gnp->gn_addend) && 57 (gnp->gn_gotref == gref)) { 58 return (gnp); 59 } 60 } 61 return (NULL); 62 } 63 64 static Xword 65 ld_calc_got_offset(Rel_desc *rdesc, Ofl_desc *ofl) 66 { 67 Os_desc *osp = ofl->ofl_osgot; 68 Sym_desc *sdp = rdesc->rel_sym; 69 Xword gotndx; 70 Gotref gref; 71 Gotndx *gnp; 72 73 if (rdesc->rel_flags & FLG_REL_DTLS) 74 gref = GOT_REF_TLSGD; 75 else if (rdesc->rel_flags & FLG_REL_MTLS) 76 gref = GOT_REF_TLSLD; 77 else if (rdesc->rel_flags & FLG_REL_STLS) 78 gref = GOT_REF_TLSIE; 79 else 80 gref = GOT_REF_GENERIC; 81 82 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, rdesc); 83 assert(gnp); 84 85 gotndx = (Xword)gnp->gn_gotndx; 86 87 if ((rdesc->rel_flags & FLG_REL_DTLS) && 88 (rdesc->rel_rtype == R_AMD64_DTPOFF64)) 89 gotndx++; 90 91 return ((Xword)(osp->os_shdr->sh_addr + (gotndx * M_GOT_ENTSIZE))); 92 } 93 94 static Word 95 ld_init_rel(Rel_desc *reld, void *reloc) 96 { 97 Rela *rel = (Rela *)reloc; 98 99 /* LINTED */ 100 reld->rel_rtype = (Word)ELF_R_TYPE(rel->r_info, M_MACH); 101 reld->rel_roffset = rel->r_offset; 102 reld->rel_raddend = rel->r_addend; 103 reld->rel_typedata = 0; 104 105 reld->rel_flags |= FLG_REL_RELA; 106 107 return ((Word)ELF_R_SYM(rel->r_info)); 108 } 109 110 static void 111 ld_mach_eflags(Ehdr *ehdr, Ofl_desc *ofl) 112 { 113 ofl->ofl_dehdr->e_flags |= ehdr->e_flags; 114 } 115 116 static void 117 ld_mach_make_dynamic(Ofl_desc *ofl, size_t *cnt) 118 { 119 if (!(ofl->ofl_flags & FLG_OF_RELOBJ)) { 120 /* 121 * Create this entry if we are going to create a PLT table. 122 */ 123 if (ofl->ofl_pltcnt) 124 (*cnt)++; /* DT_PLTGOT */ 125 } 126 } 127 128 static void 129 ld_mach_update_odynamic(Ofl_desc *ofl, Dyn **dyn) 130 { 131 if (((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) && ofl->ofl_pltcnt) { 132 (*dyn)->d_tag = DT_PLTGOT; 133 if (ofl->ofl_osgot) 134 (*dyn)->d_un.d_ptr = ofl->ofl_osgot->os_shdr->sh_addr; 135 else 136 (*dyn)->d_un.d_ptr = 0; 137 (*dyn)++; 138 } 139 } 140 141 static Xword 142 ld_calc_plt_addr(Sym_desc *sdp, Ofl_desc *ofl) 143 { 144 Xword value; 145 146 value = (Xword)(ofl->ofl_osplt->os_shdr->sh_addr) + 147 M_PLT_RESERVSZ + ((sdp->sd_aux->sa_PLTndx - 1) * M_PLT_ENTSIZE); 148 return (value); 149 } 150 151 /* 152 * Build a single plt entry - code is: 153 * JMP *name1@GOTPCREL(%rip) 154 * PUSHL $index 155 * JMP .PLT0 156 */ 157 static uchar_t pltn_entry[M_PLT_ENTSIZE] = { 158 /* 0x00 jmpq *name1@GOTPCREL(%rip) */ 0xff, 0x25, 0x00, 0x00, 0x00, 0x00, 159 /* 0x06 pushq $index */ 0x68, 0x00, 0x00, 0x00, 0x00, 160 /* 0x0b jmpq .plt0(%rip) */ 0xe9, 0x00, 0x00, 0x00, 0x00 161 /* 0x10 */ 162 }; 163 164 static uintptr_t 165 plt_entry(Ofl_desc * ofl, Sym_desc * sdp) 166 { 167 uchar_t *plt0, *pltent, *gotent; 168 Sword plt_off; 169 Word got_off; 170 Xword val1; 171 int bswap = (ofl->ofl_flags1 & FLG_OF1_ENCDIFF) != 0; 172 173 got_off = sdp->sd_aux->sa_PLTGOTndx * M_GOT_ENTSIZE; 174 plt_off = M_PLT_RESERVSZ + ((sdp->sd_aux->sa_PLTndx - 1) * 175 M_PLT_ENTSIZE); 176 plt0 = (uchar_t *)(ofl->ofl_osplt->os_outdata->d_buf); 177 pltent = plt0 + plt_off; 178 gotent = (uchar_t *)(ofl->ofl_osgot->os_outdata->d_buf) + got_off; 179 180 bcopy(pltn_entry, pltent, sizeof (pltn_entry)); 181 /* 182 * Fill in the got entry with the address of the next instruction. 183 */ 184 /* LINTED */ 185 *(Word *)gotent = ofl->ofl_osplt->os_shdr->sh_addr + plt_off + 186 M_PLT_INSSIZE; 187 if (bswap) 188 /* LINTED */ 189 *(Word *)gotent = ld_bswap_Word(*(Word *)gotent); 190 191 /* 192 * If '-z noreloc' is specified - skip the do_reloc_ld 193 * stage. 194 */ 195 if (!OFL_DO_RELOC(ofl)) 196 return (1); 197 198 /* 199 * patchup: 200 * jmpq *name1@gotpcrel(%rip) 201 * 202 * NOTE: 0x06 represents next instruction. 203 */ 204 val1 = (ofl->ofl_osgot->os_shdr->sh_addr + got_off) - 205 (ofl->ofl_osplt->os_shdr->sh_addr + plt_off) - 0x06; 206 207 if (do_reloc_ld(R_AMD64_GOTPCREL, &pltent[0x02], 208 &val1, MSG_ORIG(MSG_SYM_PLTENT), 209 MSG_ORIG(MSG_SPECFIL_PLTENT), bswap, ofl->ofl_lml) == 0) { 210 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_PLT_PLTNFAIL), 211 sdp->sd_aux->sa_PLTndx, demangle(sdp->sd_name)); 212 return (S_ERROR); 213 } 214 215 /* 216 * patchup: 217 * pushq $pltndx 218 */ 219 val1 = (Xword)(sdp->sd_aux->sa_PLTndx - 1); 220 221 if (do_reloc_ld(R_AMD64_32, &pltent[0x07], 222 &val1, MSG_ORIG(MSG_SYM_PLTENT), 223 MSG_ORIG(MSG_SPECFIL_PLTENT), bswap, ofl->ofl_lml) == 0) { 224 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_PLT_PLTNFAIL), 225 sdp->sd_aux->sa_PLTndx, demangle(sdp->sd_name)); 226 return (S_ERROR); 227 } 228 229 /* 230 * patchup: 231 * jmpq .plt0(%rip) 232 * NOTE: 0x10 represents next instruction. The rather complex 233 * series of casts is necessary to sign extend an offset into 234 * a 64-bit value while satisfying various compiler error 235 * checks. Handle with care. 236 */ 237 val1 = (Xword)((intptr_t)((uintptr_t)plt0 - 238 (uintptr_t)(&pltent[0x10]))); 239 240 if (do_reloc_ld(R_AMD64_PC32, &pltent[0x0c], 241 &val1, MSG_ORIG(MSG_SYM_PLTENT), 242 MSG_ORIG(MSG_SPECFIL_PLTENT), bswap, ofl->ofl_lml) == 0) { 243 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_PLT_PLTNFAIL), 244 sdp->sd_aux->sa_PLTndx, demangle(sdp->sd_name)); 245 return (S_ERROR); 246 } 247 248 return (1); 249 } 250 251 static uintptr_t 252 ld_perform_outreloc(Rel_desc * orsp, Ofl_desc * ofl) 253 { 254 Os_desc * relosp, * osp = 0; 255 Word ndx; 256 Xword roffset, value; 257 Sxword raddend; 258 Rela rea; 259 char *relbits; 260 Sym_desc * sdp, * psym = (Sym_desc *)0; 261 int sectmoved = 0; 262 263 raddend = orsp->rel_raddend; 264 sdp = orsp->rel_sym; 265 266 /* 267 * If the section this relocation is against has been discarded 268 * (-zignore), then also discard (skip) the relocation itself. 269 */ 270 if (orsp->rel_isdesc && ((orsp->rel_flags & 271 (FLG_REL_GOT | FLG_REL_BSS | FLG_REL_PLT | FLG_REL_NOINFO)) == 0) && 272 (orsp->rel_isdesc->is_flags & FLG_IS_DISCARD)) { 273 DBG_CALL(Dbg_reloc_discard(ofl->ofl_lml, M_MACH, orsp)); 274 return (1); 275 } 276 277 /* 278 * If this is a relocation against a move table, or expanded move 279 * table, adjust the relocation entries. 280 */ 281 if (orsp->rel_move) 282 ld_adj_movereloc(ofl, orsp); 283 284 /* 285 * If this is a relocation against a section then we need to adjust the 286 * raddend field to compensate for the new position of the input section 287 * within the new output section. 288 */ 289 if (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) { 290 if (ofl->ofl_parsyms && 291 (sdp->sd_isc->is_flags & FLG_IS_RELUPD) && 292 /* LINTED */ 293 (psym = ld_am_I_partial(orsp, orsp->rel_raddend))) { 294 DBG_CALL(Dbg_move_outsctadj(ofl->ofl_lml, psym)); 295 sectmoved = 1; 296 if (ofl->ofl_flags & FLG_OF_RELOBJ) 297 raddend = psym->sd_sym->st_value; 298 else 299 raddend = psym->sd_sym->st_value - 300 psym->sd_isc->is_osdesc->os_shdr->sh_addr; 301 /* LINTED */ 302 raddend += (Off)_elf_getxoff(psym->sd_isc->is_indata); 303 if (psym->sd_isc->is_shdr->sh_flags & SHF_ALLOC) 304 raddend += 305 psym->sd_isc->is_osdesc->os_shdr->sh_addr; 306 } else { 307 /* LINTED */ 308 raddend += (Off)_elf_getxoff(sdp->sd_isc->is_indata); 309 if (sdp->sd_isc->is_shdr->sh_flags & SHF_ALLOC) 310 raddend += 311 sdp->sd_isc->is_osdesc->os_shdr->sh_addr; 312 } 313 } 314 315 value = sdp->sd_sym->st_value; 316 317 if (orsp->rel_flags & FLG_REL_GOT) { 318 /* 319 * Note: for GOT relative relocations on amd64 320 * we discard the addend. It was relevant 321 * to the reference - not to the data item 322 * being referenced (ie: that -4 thing). 323 */ 324 raddend = 0; 325 osp = ofl->ofl_osgot; 326 roffset = ld_calc_got_offset(orsp, ofl); 327 328 } else if (orsp->rel_flags & FLG_REL_PLT) { 329 /* 330 * Note that relocations for PLT's actually 331 * cause a relocation againt the GOT. 332 */ 333 osp = ofl->ofl_osplt; 334 roffset = (ofl->ofl_osgot->os_shdr->sh_addr) + 335 sdp->sd_aux->sa_PLTGOTndx * M_GOT_ENTSIZE; 336 raddend = 0; 337 if (plt_entry(ofl, sdp) == S_ERROR) 338 return (S_ERROR); 339 340 } else if (orsp->rel_flags & FLG_REL_BSS) { 341 /* 342 * This must be a R_AMD64_COPY. For these set the roffset to 343 * point to the new symbols location. 344 */ 345 osp = ofl->ofl_isbss->is_osdesc; 346 roffset = value; 347 348 /* 349 * The raddend doesn't mean anything in a R_SPARC_COPY 350 * relocation. Null it out because it can confuse people. 351 */ 352 raddend = 0; 353 } else { 354 osp = orsp->rel_osdesc; 355 356 /* 357 * Calculate virtual offset of reference point; equals offset 358 * into section + vaddr of section for loadable sections, or 359 * offset plus section displacement for nonloadable sections. 360 */ 361 roffset = orsp->rel_roffset + 362 (Off)_elf_getxoff(orsp->rel_isdesc->is_indata); 363 if (!(ofl->ofl_flags & FLG_OF_RELOBJ)) 364 roffset += orsp->rel_isdesc->is_osdesc-> 365 os_shdr->sh_addr; 366 } 367 368 if ((osp == 0) || ((relosp = osp->os_relosdesc) == 0)) 369 relosp = ofl->ofl_osrel; 370 371 /* 372 * Assign the symbols index for the output relocation. If the 373 * relocation refers to a SECTION symbol then it's index is based upon 374 * the output sections symbols index. Otherwise the index can be 375 * derived from the symbols index itself. 376 */ 377 if (orsp->rel_rtype == R_AMD64_RELATIVE) 378 ndx = STN_UNDEF; 379 else if ((orsp->rel_flags & FLG_REL_SCNNDX) || 380 (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION)) { 381 if (sectmoved == 0) { 382 /* 383 * Check for a null input section. This can 384 * occur if this relocation references a symbol 385 * generated by sym_add_sym(). 386 */ 387 if (sdp->sd_isc && sdp->sd_isc->is_osdesc) 388 ndx = sdp->sd_isc->is_osdesc->os_identndx; 389 else 390 ndx = sdp->sd_shndx; 391 } else 392 ndx = ofl->ofl_parexpnndx; 393 } else 394 ndx = sdp->sd_symndx; 395 396 /* 397 * Add the symbols 'value' to the addend field. 398 */ 399 if (orsp->rel_flags & FLG_REL_ADVAL) 400 raddend += value; 401 402 /* 403 * The addend field for R_AMD64_DTPMOD64 means nothing. The addend 404 * is propagated in the corresponding R_AMD64_DTPOFF64 relocation. 405 */ 406 if (orsp->rel_rtype == R_AMD64_DTPMOD64) 407 raddend = 0; 408 409 relbits = (char *)relosp->os_outdata->d_buf; 410 411 rea.r_info = ELF_R_INFO(ndx, orsp->rel_rtype); 412 rea.r_offset = roffset; 413 rea.r_addend = raddend; 414 DBG_CALL(Dbg_reloc_out(ofl, ELF_DBG_LD, SHT_RELA, &rea, relosp->os_name, 415 orsp->rel_sname)); 416 417 /* 418 * Assert we haven't walked off the end of our relocation table. 419 */ 420 assert(relosp->os_szoutrels <= relosp->os_shdr->sh_size); 421 422 (void) memcpy((relbits + relosp->os_szoutrels), 423 (char *)&rea, sizeof (Rela)); 424 relosp->os_szoutrels += (Xword)sizeof (Rela); 425 426 /* 427 * Determine if this relocation is against a non-writable, allocatable 428 * section. If so we may need to provide a text relocation diagnostic. 429 * Note that relocations against the .plt (R_AMD64_JUMP_SLOT) actually 430 * result in modifications to the .got. 431 */ 432 if (orsp->rel_rtype == R_AMD64_JUMP_SLOT) 433 osp = ofl->ofl_osgot; 434 435 ld_reloc_remain_entry(orsp, osp, ofl); 436 return (1); 437 } 438 439 /* 440 * amd64 Instructions for TLS processing 441 */ 442 static uchar_t tlsinstr_gd_ie[] = { 443 /* 444 * 0x00 movq %fs:0, %rax 445 */ 446 0x64, 0x48, 0x8b, 0x04, 0x25, 447 0x00, 0x00, 0x00, 0x00, 448 /* 449 * 0x09 addq x@gottpoff(%rip), %rax 450 */ 451 0x48, 0x03, 0x05, 0x00, 0x00, 452 0x00, 0x00 453 }; 454 455 static uchar_t tlsinstr_gd_le[] = { 456 /* 457 * 0x00 movq %fs:0, %rax 458 */ 459 0x64, 0x48, 0x8b, 0x04, 0x25, 460 0x00, 0x00, 0x00, 0x00, 461 /* 462 * 0x09 leaq x@gottpoff(%rip), %rax 463 */ 464 0x48, 0x8d, 0x80, 0x00, 0x00, 465 0x00, 0x00 466 }; 467 468 static uchar_t tlsinstr_ld_le[] = { 469 /* 470 * .byte 0x66 471 */ 472 0x66, 473 /* 474 * .byte 0x66 475 */ 476 0x66, 477 /* 478 * .byte 0x66 479 */ 480 0x66, 481 /* 482 * movq %fs:0, %rax 483 */ 484 0x64, 0x48, 0x8b, 0x04, 0x25, 485 0x00, 0x00, 0x00, 0x00 486 }; 487 488 489 static Fixupret 490 tls_fixups(Ofl_desc *ofl, Rel_desc *arsp) 491 { 492 Sym_desc *sdp = arsp->rel_sym; 493 Word rtype = arsp->rel_rtype; 494 uchar_t *offset; 495 496 offset = (uchar_t *)((uintptr_t)arsp->rel_roffset + 497 (uintptr_t)_elf_getxoff(arsp->rel_isdesc->is_indata) + 498 (uintptr_t)arsp->rel_osdesc->os_outdata->d_buf); 499 500 if (sdp->sd_ref == REF_DYN_NEED) { 501 /* 502 * IE reference model 503 */ 504 switch (rtype) { 505 case R_AMD64_TLSGD: 506 /* 507 * GD -> IE 508 * 509 * Transition: 510 * 0x00 .byte 0x66 511 * 0x01 leaq x@tlsgd(%rip), %rdi 512 * 0x08 .word 0x6666 513 * 0x0a rex64 514 * 0x0b call __tls_get_addr@plt 515 * 0x10 516 * To: 517 * 0x00 movq %fs:0, %rax 518 * 0x09 addq x@gottpoff(%rip), %rax 519 * 0x10 520 */ 521 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 522 R_AMD64_GOTTPOFF, arsp)); 523 arsp->rel_rtype = R_AMD64_GOTTPOFF; 524 arsp->rel_roffset += 8; 525 arsp->rel_raddend = (Sxword)-4; 526 527 /* 528 * Adjust 'offset' to beginning of instruction 529 * sequence. 530 */ 531 offset -= 4; 532 (void) memcpy(offset, tlsinstr_gd_ie, 533 sizeof (tlsinstr_gd_ie)); 534 return (FIX_RELOC); 535 536 case R_AMD64_PLT32: 537 /* 538 * Fixup done via the TLS_GD relocation. 539 */ 540 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 541 R_AMD64_NONE, arsp)); 542 return (FIX_DONE); 543 } 544 } 545 546 /* 547 * LE reference model 548 */ 549 switch (rtype) { 550 case R_AMD64_TLSGD: 551 /* 552 * GD -> LE 553 * 554 * Transition: 555 * 0x00 .byte 0x66 556 * 0x01 leaq x@tlsgd(%rip), %rdi 557 * 0x08 .word 0x6666 558 * 0x0a rex64 559 * 0x0b call __tls_get_addr@plt 560 * 0x10 561 * To: 562 * 0x00 movq %fs:0, %rax 563 * 0x09 leaq x@tpoff(%rax), %rax 564 * 0x10 565 */ 566 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 567 R_AMD64_TPOFF32, arsp)); 568 arsp->rel_rtype = R_AMD64_TPOFF32; 569 arsp->rel_roffset += 8; 570 arsp->rel_raddend = 0; 571 572 /* 573 * Adjust 'offset' to beginning of instruction sequence. 574 */ 575 offset -= 4; 576 (void) memcpy(offset, tlsinstr_gd_le, sizeof (tlsinstr_gd_le)); 577 return (FIX_RELOC); 578 579 case R_AMD64_GOTTPOFF: 580 /* 581 * IE -> LE 582 * 583 * Transition: 584 * 0x00 movq %fs:0, %rax 585 * 0x09 addq x@gottopoff(%rip), %rax 586 * 0x10 587 * To: 588 * 0x00 movq %fs:0, %rax 589 * 0x09 leaq x@tpoff(%rax), %rax 590 * 0x10 591 */ 592 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 593 R_AMD64_TPOFF32, arsp)); 594 arsp->rel_rtype = R_AMD64_TPOFF32; 595 arsp->rel_raddend = 0; 596 597 /* 598 * Adjust 'offset' to beginning of instruction sequence. 599 */ 600 offset -= 12; 601 602 /* 603 * Same code sequence used in the GD -> LE transition. 604 */ 605 (void) memcpy(offset, tlsinstr_gd_le, sizeof (tlsinstr_gd_le)); 606 return (FIX_RELOC); 607 608 case R_AMD64_TLSLD: 609 /* 610 * LD -> LE 611 * 612 * Transition 613 * 0x00 leaq x1@tlsgd(%rip), %rdi 614 * 0x07 call __tls_get_addr@plt 615 * 0x0c 616 * To: 617 * 0x00 .byte 0x66 618 * 0x01 .byte 0x66 619 * 0x02 .byte 0x66 620 * 0x03 movq %fs:0, %rax 621 */ 622 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 623 R_AMD64_NONE, arsp)); 624 offset -= 3; 625 (void) memcpy(offset, tlsinstr_ld_le, sizeof (tlsinstr_ld_le)); 626 return (FIX_DONE); 627 628 case R_AMD64_DTPOFF32: 629 /* 630 * LD->LE 631 * 632 * Transition: 633 * 0x00 leaq x1@dtpoff(%rax), %rcx 634 * To: 635 * 0x00 leaq x1@tpoff(%rax), %rcx 636 */ 637 DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, 638 R_AMD64_TPOFF32, arsp)); 639 arsp->rel_rtype = R_AMD64_TPOFF32; 640 arsp->rel_raddend = 0; 641 return (FIX_RELOC); 642 } 643 644 return (FIX_RELOC); 645 } 646 647 static uintptr_t 648 ld_do_activerelocs(Ofl_desc *ofl) 649 { 650 Rel_desc *arsp; 651 Rel_cache *rcp; 652 Aliste idx; 653 uintptr_t return_code = 1; 654 ofl_flag_t flags = ofl->ofl_flags; 655 656 if (ofl->ofl_actrels) 657 DBG_CALL(Dbg_reloc_doact_title(ofl->ofl_lml)); 658 659 /* 660 * Process active relocations. 661 */ 662 for (APLIST_TRAVERSE(ofl->ofl_actrels, idx, rcp)) { 663 /* LINTED */ 664 for (arsp = (Rel_desc *)(rcp + 1); 665 arsp < rcp->rc_free; arsp++) { 666 uchar_t *addr; 667 Xword value; 668 Sym_desc *sdp; 669 const char *ifl_name; 670 Xword refaddr; 671 int moved = 0; 672 Gotref gref; 673 674 /* 675 * If the section this relocation is against has been 676 * discarded (-zignore), then discard (skip) the 677 * relocation itself. 678 */ 679 if ((arsp->rel_isdesc->is_flags & FLG_IS_DISCARD) && 680 ((arsp->rel_flags & 681 (FLG_REL_GOT | FLG_REL_BSS | 682 FLG_REL_PLT | FLG_REL_NOINFO)) == 0)) { 683 DBG_CALL(Dbg_reloc_discard(ofl->ofl_lml, 684 M_MACH, arsp)); 685 continue; 686 } 687 688 /* 689 * We determine what the 'got reference' 690 * model (if required) is at this point. This 691 * needs to be done before tls_fixup() since 692 * it may 'transition' our instructions. 693 * 694 * The got table entries have already been assigned, 695 * and we bind to those initial entries. 696 */ 697 if (arsp->rel_flags & FLG_REL_DTLS) 698 gref = GOT_REF_TLSGD; 699 else if (arsp->rel_flags & FLG_REL_MTLS) 700 gref = GOT_REF_TLSLD; 701 else if (arsp->rel_flags & FLG_REL_STLS) 702 gref = GOT_REF_TLSIE; 703 else 704 gref = GOT_REF_GENERIC; 705 706 /* 707 * Perform any required TLS fixups. 708 */ 709 if (arsp->rel_flags & FLG_REL_TLSFIX) { 710 Fixupret ret; 711 712 if ((ret = tls_fixups(ofl, arsp)) == FIX_ERROR) 713 return (S_ERROR); 714 if (ret == FIX_DONE) 715 continue; 716 } 717 718 /* 719 * If this is a relocation against a move table, or 720 * expanded move table, adjust the relocation entries. 721 */ 722 if (arsp->rel_move) 723 ld_adj_movereloc(ofl, arsp); 724 725 sdp = arsp->rel_sym; 726 refaddr = arsp->rel_roffset + 727 (Off)_elf_getxoff(arsp->rel_isdesc->is_indata); 728 729 if ((arsp->rel_flags & FLG_REL_CLVAL) || 730 (arsp->rel_flags & FLG_REL_GOTCL)) 731 value = 0; 732 else if (ELF_ST_TYPE(sdp->sd_sym->st_info) == 733 STT_SECTION) { 734 Sym_desc *sym; 735 736 /* 737 * The value for a symbol pointing to a SECTION 738 * is based off of that sections position. 739 */ 740 if ((sdp->sd_isc->is_flags & FLG_IS_RELUPD) && 741 /* LINTED */ 742 (sym = ld_am_I_partial(arsp, 743 arsp->rel_raddend))) { 744 /* 745 * The symbol was moved, so adjust 746 * the value relative to the new 747 * section. 748 */ 749 value = sym->sd_sym->st_value; 750 moved = 1; 751 752 /* 753 * The original raddend covers the 754 * displacement from the section start 755 * to the desired address. The value 756 * computed above gets us from the 757 * section start to the start of the 758 * symbol range. Adjust the old raddend 759 * to remove the offset from section 760 * start to symbol start, leaving the 761 * displacement within the range of 762 * the symbol. 763 */ 764 arsp->rel_raddend -= 765 sym->sd_osym->st_value; 766 } else { 767 value = _elf_getxoff( 768 sdp->sd_isc->is_indata); 769 if (sdp->sd_isc->is_shdr->sh_flags & 770 SHF_ALLOC) 771 value += 772 sdp->sd_isc->is_osdesc-> 773 os_shdr->sh_addr; 774 } 775 if (sdp->sd_isc->is_shdr->sh_flags & SHF_TLS) 776 value -= ofl->ofl_tlsphdr->p_vaddr; 777 778 } else if (IS_SIZE(arsp->rel_rtype)) { 779 /* 780 * Size relocations require the symbols size. 781 */ 782 value = sdp->sd_sym->st_size; 783 } else { 784 /* 785 * Else the value is the symbols value. 786 */ 787 value = sdp->sd_sym->st_value; 788 } 789 790 /* 791 * Relocation against the GLOBAL_OFFSET_TABLE. 792 */ 793 if (arsp->rel_flags & FLG_REL_GOT) 794 arsp->rel_osdesc = ofl->ofl_osgot; 795 796 /* 797 * If loadable and not producing a relocatable object 798 * add the sections virtual address to the reference 799 * address. 800 */ 801 if ((arsp->rel_flags & FLG_REL_LOAD) && 802 ((flags & FLG_OF_RELOBJ) == 0)) 803 refaddr += arsp->rel_isdesc->is_osdesc-> 804 os_shdr->sh_addr; 805 806 /* 807 * If this entry has a PLT assigned to it, it's 808 * value is actually the address of the PLT (and 809 * not the address of the function). 810 */ 811 if (IS_PLT(arsp->rel_rtype)) { 812 if (sdp->sd_aux && sdp->sd_aux->sa_PLTndx) 813 value = ld_calc_plt_addr(sdp, ofl); 814 } 815 816 /* 817 * Add relocations addend to value. Add extra 818 * relocation addend if needed. 819 * 820 * Note: for GOT relative relocations on amd64 821 * we discard the addend. It was relevant 822 * to the reference - not to the data item 823 * being referenced (ie: that -4 thing). 824 */ 825 if ((arsp->rel_flags & FLG_REL_GOT) == 0) 826 value += arsp->rel_raddend; 827 828 /* 829 * Determine whether the value needs further adjustment. 830 * Filter through the attributes of the relocation to 831 * determine what adjustment is required. Note, many 832 * of the following cases are only applicable when a 833 * .got is present. As a .got is not generated when a 834 * relocatable object is being built, any adjustments 835 * that require a .got need to be skipped. 836 */ 837 if ((arsp->rel_flags & FLG_REL_GOT) && 838 ((flags & FLG_OF_RELOBJ) == 0)) { 839 Xword R1addr; 840 uintptr_t R2addr; 841 Word gotndx; 842 Gotndx *gnp; 843 844 /* 845 * Perform relocation against GOT table. Since 846 * this doesn't fit exactly into a relocation 847 * we place the appropriate byte in the GOT 848 * directly 849 * 850 * Calculate offset into GOT at which to apply 851 * the relocation. 852 */ 853 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, 854 ofl, arsp); 855 assert(gnp); 856 857 if (arsp->rel_rtype == R_AMD64_DTPOFF64) 858 gotndx = gnp->gn_gotndx + 1; 859 else 860 gotndx = gnp->gn_gotndx; 861 862 R1addr = (Xword)(gotndx * M_GOT_ENTSIZE); 863 864 /* 865 * Add the GOTs data's offset. 866 */ 867 R2addr = R1addr + (uintptr_t) 868 arsp->rel_osdesc->os_outdata->d_buf; 869 870 DBG_CALL(Dbg_reloc_doact(ofl->ofl_lml, 871 ELF_DBG_LD, M_MACH, SHT_RELA, 872 arsp->rel_rtype, R1addr, value, 873 arsp->rel_sname, arsp->rel_osdesc)); 874 875 /* 876 * And do it. 877 */ 878 if (ofl->ofl_flags1 & FLG_OF1_ENCDIFF) 879 *(Xword *)R2addr = 880 ld_bswap_Xword(value); 881 else 882 *(Xword *)R2addr = value; 883 continue; 884 885 } else if (IS_GOT_BASED(arsp->rel_rtype) && 886 ((flags & FLG_OF_RELOBJ) == 0)) { 887 value -= ofl->ofl_osgot->os_shdr->sh_addr; 888 889 } else if (IS_GOTPCREL(arsp->rel_rtype) && 890 ((flags & FLG_OF_RELOBJ) == 0)) { 891 Gotndx *gnp; 892 893 /* 894 * Calculation: 895 * G + GOT + A - P 896 */ 897 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, 898 gref, ofl, arsp); 899 assert(gnp); 900 value = (Xword)(ofl->ofl_osgot->os_shdr-> 901 sh_addr) + ((Xword)gnp->gn_gotndx * 902 M_GOT_ENTSIZE) + arsp->rel_raddend - 903 refaddr; 904 905 } else if (IS_GOT_PC(arsp->rel_rtype) && 906 ((flags & FLG_OF_RELOBJ) == 0)) { 907 value = (Xword)(ofl->ofl_osgot->os_shdr-> 908 sh_addr) - refaddr + arsp->rel_raddend; 909 910 } else if ((IS_PC_RELATIVE(arsp->rel_rtype)) && 911 (((flags & FLG_OF_RELOBJ) == 0) || 912 (arsp->rel_osdesc == sdp->sd_isc->is_osdesc))) { 913 value -= refaddr; 914 915 } else if (IS_TLS_INS(arsp->rel_rtype) && 916 IS_GOT_RELATIVE(arsp->rel_rtype) && 917 ((flags & FLG_OF_RELOBJ) == 0)) { 918 Gotndx *gnp; 919 920 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, 921 ofl, arsp); 922 assert(gnp); 923 value = (Xword)gnp->gn_gotndx * M_GOT_ENTSIZE; 924 925 } else if (IS_GOT_RELATIVE(arsp->rel_rtype) && 926 ((flags & FLG_OF_RELOBJ) == 0)) { 927 Gotndx *gnp; 928 929 gnp = ld_find_got_ndx(sdp->sd_GOTndxs, 930 gref, ofl, arsp); 931 assert(gnp); 932 value = (Xword)gnp->gn_gotndx * M_GOT_ENTSIZE; 933 934 } else if ((arsp->rel_flags & FLG_REL_STLS) && 935 ((flags & FLG_OF_RELOBJ) == 0)) { 936 Xword tlsstatsize; 937 938 /* 939 * This is the LE TLS reference model. Static 940 * offset is hard-coded. 941 */ 942 tlsstatsize = 943 S_ROUND(ofl->ofl_tlsphdr->p_memsz, 944 M_TLSSTATALIGN); 945 value = tlsstatsize - value; 946 947 /* 948 * Since this code is fixed up, it assumes a 949 * negative offset that can be added to the 950 * thread pointer. 951 */ 952 if (arsp->rel_rtype == R_AMD64_TPOFF32) 953 value = -value; 954 } 955 956 if (arsp->rel_isdesc->is_file) 957 ifl_name = arsp->rel_isdesc->is_file->ifl_name; 958 else 959 ifl_name = MSG_INTL(MSG_STR_NULL); 960 961 /* 962 * Make sure we have data to relocate. Compiler and 963 * assembler developers have been known to generate 964 * relocations against invalid sections (normally .bss), 965 * so for their benefit give them sufficient information 966 * to help analyze the problem. End users should never 967 * see this. 968 */ 969 if (arsp->rel_isdesc->is_indata->d_buf == 0) { 970 Conv_inv_buf_t inv_buf; 971 972 eprintf(ofl->ofl_lml, ERR_FATAL, 973 MSG_INTL(MSG_REL_EMPTYSEC), 974 conv_reloc_amd64_type(arsp->rel_rtype, 975 0, &inv_buf), ifl_name, 976 demangle(arsp->rel_sname), 977 EC_WORD(arsp->rel_isdesc->is_scnndx), 978 arsp->rel_isdesc->is_name); 979 return (S_ERROR); 980 } 981 982 /* 983 * Get the address of the data item we need to modify. 984 */ 985 addr = (uchar_t *)((uintptr_t)arsp->rel_roffset + 986 (uintptr_t)_elf_getxoff(arsp->rel_isdesc-> 987 is_indata)); 988 989 DBG_CALL(Dbg_reloc_doact(ofl->ofl_lml, ELF_DBG_LD, 990 M_MACH, SHT_RELA, arsp->rel_rtype, EC_NATPTR(addr), 991 value, arsp->rel_sname, arsp->rel_osdesc)); 992 addr += (uintptr_t)arsp->rel_osdesc->os_outdata->d_buf; 993 994 if ((((uintptr_t)addr - (uintptr_t)ofl->ofl_nehdr) > 995 ofl->ofl_size) || (arsp->rel_roffset > 996 arsp->rel_osdesc->os_shdr->sh_size)) { 997 int class; 998 Conv_inv_buf_t inv_buf; 999 1000 if (((uintptr_t)addr - 1001 (uintptr_t)ofl->ofl_nehdr) > ofl->ofl_size) 1002 class = ERR_FATAL; 1003 else 1004 class = ERR_WARNING; 1005 1006 eprintf(ofl->ofl_lml, class, 1007 MSG_INTL(MSG_REL_INVALOFFSET), 1008 conv_reloc_amd64_type(arsp->rel_rtype, 1009 0, &inv_buf), ifl_name, 1010 EC_WORD(arsp->rel_isdesc->is_scnndx), 1011 arsp->rel_isdesc->is_name, 1012 demangle(arsp->rel_sname), 1013 EC_ADDR((uintptr_t)addr - 1014 (uintptr_t)ofl->ofl_nehdr)); 1015 1016 if (class == ERR_FATAL) { 1017 return_code = S_ERROR; 1018 continue; 1019 } 1020 } 1021 1022 /* 1023 * The relocation is additive. Ignore the previous 1024 * symbol value if this local partial symbol is 1025 * expanded. 1026 */ 1027 if (moved) 1028 value -= *addr; 1029 1030 /* 1031 * If '-z noreloc' is specified - skip the do_reloc_ld 1032 * stage. 1033 */ 1034 if (OFL_DO_RELOC(ofl)) { 1035 /* 1036 * If this is a PROGBITS section and the 1037 * running linker has a different byte order 1038 * than the target host, tell do_reloc_ld() 1039 * to swap bytes. 1040 */ 1041 if (do_reloc_ld((uchar_t)arsp->rel_rtype, 1042 addr, &value, arsp->rel_sname, ifl_name, 1043 OFL_SWAP_RELOC_DATA(ofl, arsp), 1044 ofl->ofl_lml) == 0) 1045 return_code = S_ERROR; 1046 } 1047 } 1048 } 1049 return (return_code); 1050 } 1051 1052 static uintptr_t 1053 ld_add_outrel(Word flags, Rel_desc *rsp, Ofl_desc *ofl) 1054 { 1055 Rel_desc *orsp; 1056 Rel_cache *rcp; 1057 Sym_desc *sdp = rsp->rel_sym; 1058 static size_t nextsize = 0; 1059 1060 /* 1061 * Static executables *do not* want any relocations against them. 1062 * Since our engine still creates relocations against a WEAK UNDEFINED 1063 * symbol in a static executable, it's best to disable them here 1064 * instead of through out the relocation code. 1065 */ 1066 if ((ofl->ofl_flags & (FLG_OF_STATIC | FLG_OF_EXEC)) == 1067 (FLG_OF_STATIC | FLG_OF_EXEC)) 1068 return (1); 1069 1070 /* 1071 * Obtain the new available relocation cache entry. 1072 */ 1073 if ((rcp = ld_add_rel_cache(ofl, &ofl->ofl_outrels, &nextsize, 1074 REL_LOIDESCNO, REL_HOIDESCNO)) == (Rel_cache *)S_ERROR) 1075 return (S_ERROR); 1076 1077 orsp = rcp->rc_free; 1078 1079 /* 1080 * If we are adding a output relocation against a section 1081 * symbol (non-RELATIVE) then mark that section. These sections 1082 * will be added to the .dynsym symbol table. 1083 */ 1084 if (sdp && (rsp->rel_rtype != M_R_RELATIVE) && 1085 ((flags & FLG_REL_SCNNDX) || 1086 (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION))) { 1087 1088 /* 1089 * If this is a COMMON symbol - no output section 1090 * exists yet - (it's created as part of sym_validate()). 1091 * So - we mark here that when it's created it should 1092 * be tagged with the FLG_OS_OUTREL flag. 1093 */ 1094 if ((sdp->sd_flags & FLG_SY_SPECSEC) && 1095 (sdp->sd_sym->st_shndx == SHN_COMMON)) { 1096 if (ELF_ST_TYPE(sdp->sd_sym->st_info) != STT_TLS) 1097 ofl->ofl_flags1 |= FLG_OF1_BSSOREL; 1098 else 1099 ofl->ofl_flags1 |= FLG_OF1_TLSOREL; 1100 } else { 1101 Os_desc *osp = sdp->sd_isc->is_osdesc; 1102 1103 if (osp && ((osp->os_flags & FLG_OS_OUTREL) == 0)) { 1104 ofl->ofl_dynshdrcnt++; 1105 osp->os_flags |= FLG_OS_OUTREL; 1106 } 1107 } 1108 } 1109 1110 *orsp = *rsp; 1111 orsp->rel_flags |= flags; 1112 1113 rcp->rc_free++; 1114 ofl->ofl_outrelscnt++; 1115 1116 if (flags & FLG_REL_GOT) 1117 ofl->ofl_relocgotsz += (Xword)sizeof (Rela); 1118 else if (flags & FLG_REL_PLT) 1119 ofl->ofl_relocpltsz += (Xword)sizeof (Rela); 1120 else if (flags & FLG_REL_BSS) 1121 ofl->ofl_relocbsssz += (Xword)sizeof (Rela); 1122 else if (flags & FLG_REL_NOINFO) 1123 ofl->ofl_relocrelsz += (Xword)sizeof (Rela); 1124 else 1125 orsp->rel_osdesc->os_szoutrels += (Xword)sizeof (Rela); 1126 1127 if (orsp->rel_rtype == M_R_RELATIVE) 1128 ofl->ofl_relocrelcnt++; 1129 1130 /* 1131 * We don't perform sorting on PLT relocations because 1132 * they have already been assigned a PLT index and if we 1133 * were to sort them we would have to re-assign the plt indexes. 1134 */ 1135 if (!(flags & FLG_REL_PLT)) 1136 ofl->ofl_reloccnt++; 1137 1138 /* 1139 * Insure a GLOBAL_OFFSET_TABLE is generated if required. 1140 */ 1141 if (IS_GOT_REQUIRED(orsp->rel_rtype)) 1142 ofl->ofl_flags |= FLG_OF_BLDGOT; 1143 1144 /* 1145 * Identify and possibly warn of a displacement relocation. 1146 */ 1147 if (orsp->rel_flags & FLG_REL_DISP) { 1148 ofl->ofl_dtflags_1 |= DF_1_DISPRELPND; 1149 1150 if (ofl->ofl_flags & FLG_OF_VERBOSE) 1151 ld_disp_errmsg(MSG_INTL(MSG_REL_DISPREL4), orsp, ofl); 1152 } 1153 DBG_CALL(Dbg_reloc_ors_entry(ofl->ofl_lml, ELF_DBG_LD, SHT_RELA, 1154 M_MACH, orsp)); 1155 return (1); 1156 } 1157 1158 /* 1159 * process relocation for a LOCAL symbol 1160 */ 1161 static uintptr_t 1162 ld_reloc_local(Rel_desc * rsp, Ofl_desc * ofl) 1163 { 1164 ofl_flag_t flags = ofl->ofl_flags; 1165 Sym_desc *sdp = rsp->rel_sym; 1166 Word shndx = sdp->sd_sym->st_shndx; 1167 Word ortype = rsp->rel_rtype; 1168 1169 /* 1170 * if ((shared object) and (not pc relative relocation) and 1171 * (not against ABS symbol)) 1172 * then 1173 * build R_AMD64_RELATIVE 1174 * fi 1175 */ 1176 if ((flags & FLG_OF_SHAROBJ) && (rsp->rel_flags & FLG_REL_LOAD) && 1177 !(IS_PC_RELATIVE(rsp->rel_rtype)) && !(IS_SIZE(rsp->rel_rtype)) && 1178 !(IS_GOT_BASED(rsp->rel_rtype)) && 1179 !(rsp->rel_isdesc != NULL && 1180 (rsp->rel_isdesc->is_shdr->sh_type == SHT_SUNW_dof)) && 1181 (((sdp->sd_flags & FLG_SY_SPECSEC) == 0) || 1182 (shndx != SHN_ABS) || (sdp->sd_aux && sdp->sd_aux->sa_symspec))) { 1183 1184 /* 1185 * R_AMD64_RELATIVE updates a 64bit address, if this 1186 * relocation isn't a 64bit binding then we can not 1187 * simplify it to a RELATIVE relocation. 1188 */ 1189 if (reloc_table[ortype].re_fsize != sizeof (Addr)) { 1190 return (ld_add_outrel(0, rsp, ofl)); 1191 } 1192 1193 rsp->rel_rtype = R_AMD64_RELATIVE; 1194 if (ld_add_outrel(FLG_REL_ADVAL, rsp, ofl) == S_ERROR) 1195 return (S_ERROR); 1196 rsp->rel_rtype = ortype; 1197 return (1); 1198 } 1199 1200 /* 1201 * If the relocation is against a 'non-allocatable' section 1202 * and we can not resolve it now - then give a warning 1203 * message. 1204 * 1205 * We can not resolve the symbol if either: 1206 * a) it's undefined 1207 * b) it's defined in a shared library and a 1208 * COPY relocation hasn't moved it to the executable 1209 * 1210 * Note: because we process all of the relocations against the 1211 * text segment before any others - we know whether 1212 * or not a copy relocation will be generated before 1213 * we get here (see reloc_init()->reloc_segments()). 1214 */ 1215 if (!(rsp->rel_flags & FLG_REL_LOAD) && 1216 ((shndx == SHN_UNDEF) || 1217 ((sdp->sd_ref == REF_DYN_NEED) && 1218 ((sdp->sd_flags & FLG_SY_MVTOCOMM) == 0)))) { 1219 Conv_inv_buf_t inv_buf; 1220 1221 /* 1222 * If the relocation is against a SHT_SUNW_ANNOTATE 1223 * section - then silently ignore that the relocation 1224 * can not be resolved. 1225 */ 1226 if (rsp->rel_osdesc && 1227 (rsp->rel_osdesc->os_shdr->sh_type == SHT_SUNW_ANNOTATE)) 1228 return (0); 1229 (void) eprintf(ofl->ofl_lml, ERR_WARNING, 1230 MSG_INTL(MSG_REL_EXTERNSYM), 1231 conv_reloc_amd64_type(rsp->rel_rtype, 0, &inv_buf), 1232 rsp->rel_isdesc->is_file->ifl_name, 1233 demangle(rsp->rel_sname), rsp->rel_osdesc->os_name); 1234 return (1); 1235 } 1236 1237 /* 1238 * Perform relocation. 1239 */ 1240 return (ld_add_actrel(NULL, rsp, ofl)); 1241 } 1242 1243 1244 static uintptr_t 1245 ld_reloc_TLS(Boolean local, Rel_desc * rsp, Ofl_desc * ofl) 1246 { 1247 Word rtype = rsp->rel_rtype; 1248 Sym_desc *sdp = rsp->rel_sym; 1249 ofl_flag_t flags = ofl->ofl_flags; 1250 Gotndx *gnp; 1251 1252 /* 1253 * If we're building an executable - use either the IE or LE access 1254 * model. If we're building a shared object process any IE model. 1255 */ 1256 if ((flags & FLG_OF_EXEC) || (IS_TLS_IE(rtype))) { 1257 /* 1258 * Set the DF_STATIC_TLS flag. 1259 */ 1260 ofl->ofl_dtflags |= DF_STATIC_TLS; 1261 1262 if (!local || ((flags & FLG_OF_EXEC) == 0)) { 1263 /* 1264 * Assign a GOT entry for static TLS references. 1265 */ 1266 if ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs, 1267 GOT_REF_TLSIE, ofl, rsp)) == NULL) { 1268 1269 if (ld_assign_got_TLS(local, rsp, ofl, sdp, 1270 gnp, GOT_REF_TLSIE, FLG_REL_STLS, 1271 rtype, R_AMD64_TPOFF64, 0) == S_ERROR) 1272 return (S_ERROR); 1273 } 1274 1275 /* 1276 * IE access model. 1277 */ 1278 if (IS_TLS_IE(rtype)) 1279 return (ld_add_actrel(FLG_REL_STLS, rsp, ofl)); 1280 1281 /* 1282 * Fixups are required for other executable models. 1283 */ 1284 return (ld_add_actrel((FLG_REL_TLSFIX | FLG_REL_STLS), 1285 rsp, ofl)); 1286 } 1287 1288 /* 1289 * LE access model. 1290 */ 1291 if (IS_TLS_LE(rtype)) 1292 return (ld_add_actrel(FLG_REL_STLS, rsp, ofl)); 1293 1294 return (ld_add_actrel((FLG_REL_TLSFIX | FLG_REL_STLS), 1295 rsp, ofl)); 1296 } 1297 1298 /* 1299 * Building a shared object. 1300 * 1301 * Assign a GOT entry for a dynamic TLS reference. 1302 */ 1303 if (IS_TLS_LD(rtype) && ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs, 1304 GOT_REF_TLSLD, ofl, rsp)) == NULL)) { 1305 1306 if (ld_assign_got_TLS(local, rsp, ofl, sdp, gnp, GOT_REF_TLSLD, 1307 FLG_REL_MTLS, rtype, R_AMD64_DTPMOD64, NULL) == S_ERROR) 1308 return (S_ERROR); 1309 1310 } else if (IS_TLS_GD(rtype) && 1311 ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs, GOT_REF_TLSGD, 1312 ofl, rsp)) == NULL)) { 1313 1314 if (ld_assign_got_TLS(local, rsp, ofl, sdp, gnp, GOT_REF_TLSGD, 1315 FLG_REL_DTLS, rtype, R_AMD64_DTPMOD64, 1316 R_AMD64_DTPOFF64) == S_ERROR) 1317 return (S_ERROR); 1318 } 1319 1320 if (IS_TLS_LD(rtype)) 1321 return (ld_add_actrel(FLG_REL_MTLS, rsp, ofl)); 1322 1323 return (ld_add_actrel(FLG_REL_DTLS, rsp, ofl)); 1324 } 1325 1326 /* ARGSUSED5 */ 1327 static uintptr_t 1328 ld_assign_got_ndx(Alist **alpp, Gotndx *pgnp, Gotref gref, Ofl_desc *ofl, 1329 Rel_desc *rsp, Sym_desc *sdp) 1330 { 1331 Xword raddend; 1332 Gotndx gn, *gnp; 1333 Aliste idx; 1334 uint_t gotents; 1335 1336 raddend = rsp->rel_raddend; 1337 if (pgnp && (pgnp->gn_addend == raddend) && (pgnp->gn_gotref == gref)) 1338 return (1); 1339 1340 if ((gref == GOT_REF_TLSGD) || (gref == GOT_REF_TLSLD)) 1341 gotents = 2; 1342 else 1343 gotents = 1; 1344 1345 gn.gn_addend = raddend; 1346 gn.gn_gotndx = ofl->ofl_gotcnt; 1347 gn.gn_gotref = gref; 1348 1349 ofl->ofl_gotcnt += gotents; 1350 1351 if (gref == GOT_REF_TLSLD) { 1352 if (ofl->ofl_tlsldgotndx == NULL) { 1353 if ((gnp = libld_malloc(sizeof (Gotndx))) == NULL) 1354 return (S_ERROR); 1355 (void) memcpy(gnp, &gn, sizeof (Gotndx)); 1356 ofl->ofl_tlsldgotndx = gnp; 1357 } 1358 return (1); 1359 } 1360 1361 idx = 0; 1362 for (ALIST_TRAVERSE(*alpp, idx, gnp)) { 1363 if (gnp->gn_addend > raddend) 1364 break; 1365 } 1366 1367 /* 1368 * GOT indexes are maintained on an Alist, where there is typically 1369 * only one index. The usage of this list is to scan the list to find 1370 * an index, and then apply that index immediately to a relocation. 1371 * Thus there are no external references to these GOT index structures 1372 * that can be compromised by the Alist being reallocated. 1373 */ 1374 if (alist_insert(alpp, &gn, sizeof (Gotndx), 1375 AL_CNT_SDP_GOT, idx) == NULL) 1376 return (S_ERROR); 1377 1378 return (1); 1379 } 1380 1381 static void 1382 ld_assign_plt_ndx(Sym_desc * sdp, Ofl_desc *ofl) 1383 { 1384 sdp->sd_aux->sa_PLTndx = 1 + ofl->ofl_pltcnt++; 1385 sdp->sd_aux->sa_PLTGOTndx = ofl->ofl_gotcnt++; 1386 ofl->ofl_flags |= FLG_OF_BLDGOT; 1387 } 1388 1389 static uchar_t plt0_template[M_PLT_ENTSIZE] = { 1390 /* 0x00 PUSHQ GOT+8(%rip) */ 0xff, 0x35, 0x00, 0x00, 0x00, 0x00, 1391 /* 0x06 JMP *GOT+16(%rip) */ 0xff, 0x25, 0x00, 0x00, 0x00, 0x00, 1392 /* 0x0c NOP */ 0x90, 1393 /* 0x0d NOP */ 0x90, 1394 /* 0x0e NOP */ 0x90, 1395 /* 0x0f NOP */ 0x90 1396 }; 1397 1398 /* 1399 * Initializes .got[0] with the _DYNAMIC symbol value. 1400 */ 1401 static uintptr_t 1402 ld_fillin_gotplt(Ofl_desc *ofl) 1403 { 1404 int bswap = (ofl->ofl_flags1 & FLG_OF1_ENCDIFF) != 0; 1405 1406 if (ofl->ofl_osgot) { 1407 Sym_desc *sdp; 1408 1409 if ((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_DYNAMIC_U), 1410 SYM_NOHASH, 0, ofl)) != NULL) { 1411 uchar_t *genptr; 1412 1413 genptr = ((uchar_t *)ofl->ofl_osgot->os_outdata->d_buf + 1414 (M_GOT_XDYNAMIC * M_GOT_ENTSIZE)); 1415 /* LINTED */ 1416 *(Xword *)genptr = sdp->sd_sym->st_value; 1417 if (bswap) 1418 /* LINTED */ 1419 *(Xword *)genptr = 1420 /* LINTED */ 1421 ld_bswap_Xword(*(Xword *)genptr); 1422 } 1423 } 1424 1425 /* 1426 * Fill in the reserved slot in the procedure linkage table the first 1427 * entry is: 1428 * 0x00 PUSHQ GOT+8(%rip) # GOT[1] 1429 * 0x06 JMP *GOT+16(%rip) # GOT[2] 1430 * 0x0c NOP 1431 * 0x0d NOP 1432 * 0x0e NOP 1433 * 0x0f NOP 1434 */ 1435 if ((ofl->ofl_flags & FLG_OF_DYNAMIC) && ofl->ofl_osplt) { 1436 uchar_t *pltent; 1437 Xword val1; 1438 1439 pltent = (uchar_t *)ofl->ofl_osplt->os_outdata->d_buf; 1440 bcopy(plt0_template, pltent, sizeof (plt0_template)); 1441 1442 /* 1443 * If '-z noreloc' is specified - skip the do_reloc_ld 1444 * stage. 1445 */ 1446 if (!OFL_DO_RELOC(ofl)) 1447 return (1); 1448 1449 /* 1450 * filin: 1451 * PUSHQ GOT + 8(%rip) 1452 * 1453 * Note: 0x06 below represents the offset to the 1454 * next instruction - which is what %rip will 1455 * be pointing at. 1456 */ 1457 val1 = (ofl->ofl_osgot->os_shdr->sh_addr) + 1458 (M_GOT_XLINKMAP * M_GOT_ENTSIZE) - 1459 ofl->ofl_osplt->os_shdr->sh_addr - 0x06; 1460 1461 if (do_reloc_ld(R_AMD64_GOTPCREL, &pltent[0x02], 1462 &val1, MSG_ORIG(MSG_SYM_PLTENT), 1463 MSG_ORIG(MSG_SPECFIL_PLTENT), bswap, ofl->ofl_lml) == 0) { 1464 eprintf(ofl->ofl_lml, ERR_FATAL, 1465 MSG_INTL(MSG_PLT_PLT0FAIL)); 1466 return (S_ERROR); 1467 } 1468 1469 /* 1470 * filin: 1471 * JMP *GOT+16(%rip) 1472 */ 1473 val1 = (ofl->ofl_osgot->os_shdr->sh_addr) + 1474 (M_GOT_XRTLD * M_GOT_ENTSIZE) - 1475 ofl->ofl_osplt->os_shdr->sh_addr - 0x0c; 1476 1477 if (do_reloc_ld(R_AMD64_GOTPCREL, &pltent[0x08], 1478 &val1, MSG_ORIG(MSG_SYM_PLTENT), 1479 MSG_ORIG(MSG_SPECFIL_PLTENT), bswap, ofl->ofl_lml) == 0) { 1480 eprintf(ofl->ofl_lml, ERR_FATAL, 1481 MSG_INTL(MSG_PLT_PLT0FAIL)); 1482 return (S_ERROR); 1483 } 1484 } 1485 1486 return (1); 1487 } 1488 1489 1490 1491 /* 1492 * Template for generating "void (*)(void)" function 1493 */ 1494 static const uchar_t nullfunc_tmpl[] = { /* amd64 */ 1495 /* 0x00 */ 0x55, /* pushq %rbp */ 1496 /* 0x01 */ 0x48, 0x8b, 0xec, /* movq %rsp,%rbp */ 1497 /* 0x04 */ 0x48, 0x8b, 0xe5, /* movq %rbp,%rsp */ 1498 /* 0x07 */ 0x5d, /* popq %rbp */ 1499 /* 0x08 */ 0xc3 /* ret */ 1500 }; 1501 1502 1503 /* 1504 * Return the ld_targ definition for this target. 1505 */ 1506 const Target * 1507 ld_targ_init_x86(void) 1508 { 1509 static const Target _ld_targ = { 1510 { /* Target_mach */ 1511 M_MACH, /* m_mach */ 1512 M_MACHPLUS, /* m_machplus */ 1513 M_FLAGSPLUS, /* m_flagsplus */ 1514 M_CLASS, /* m_class */ 1515 M_DATA, /* m_data */ 1516 1517 M_SEGM_ALIGN, /* m_segm_align */ 1518 M_SEGM_ORIGIN, /* m_segm_origin */ 1519 M_SEGM_AORIGIN, /* m_segm_aorigin */ 1520 M_DATASEG_PERM, /* m_dataseg_perm */ 1521 M_WORD_ALIGN, /* m_word_align */ 1522 MSG_ORIG(MSG_PTH_RTLD_AMD64), /* m_def_interp */ 1523 1524 /* Relocation type codes */ 1525 M_R_ARRAYADDR, /* m_r_arrayaddr */ 1526 M_R_COPY, /* m_r_copy */ 1527 M_R_GLOB_DAT, /* m_r_glob_dat */ 1528 M_R_JMP_SLOT, /* m_r_jmp_slot */ 1529 M_R_NUM, /* m_r_num */ 1530 M_R_NONE, /* m_r_none */ 1531 M_R_RELATIVE, /* m_r_relative */ 1532 M_R_REGISTER, /* m_r_register */ 1533 1534 /* Relocation related constants */ 1535 M_REL_DT_COUNT, /* m_rel_dt_count */ 1536 M_REL_DT_ENT, /* m_rel_dt_ent */ 1537 M_REL_DT_SIZE, /* m_rel_dt_size */ 1538 M_REL_DT_TYPE, /* m_rel_dt_type */ 1539 M_REL_SHT_TYPE, /* m_rel_sht_type */ 1540 1541 /* GOT related constants */ 1542 M_GOT_ENTSIZE, /* m_got_entsize */ 1543 M_GOT_XNumber, /* m_got_xnumber */ 1544 1545 /* PLT related constants */ 1546 M_PLT_ALIGN, /* m_plt_align */ 1547 M_PLT_ENTSIZE, /* m_plt_entsize */ 1548 M_PLT_RESERVSZ, /* m_plt_reservsz */ 1549 M_PLT_SHF_FLAGS, /* m_plt_shf_flags */ 1550 1551 /* Section type of .eh_frame/.eh_frame_hdr sections */ 1552 SHT_AMD64_UNWIND, /* m_sht_unwind */ 1553 1554 M_DT_REGISTER, /* m_dt_register */ 1555 }, 1556 { /* Target_machid */ 1557 M_ID_ARRAY, /* id_array */ 1558 M_ID_BSS, /* id_bss */ 1559 M_ID_CAP, /* id_cap */ 1560 M_ID_DATA, /* id_data */ 1561 M_ID_DYNAMIC, /* id_dynamic */ 1562 M_ID_DYNSORT, /* id_dynsort */ 1563 M_ID_DYNSTR, /* id_dynstr */ 1564 M_ID_DYNSYM, /* id_dynsym */ 1565 M_ID_DYNSYM_NDX, /* id_dynsym_ndx */ 1566 M_ID_GOT, /* id_got */ 1567 M_ID_UNKNOWN, /* id_gotdata (unused) */ 1568 M_ID_HASH, /* id_hash */ 1569 M_ID_INTERP, /* id_interp */ 1570 M_ID_LBSS, /* id_lbss */ 1571 M_ID_LDYNSYM, /* id_ldynsym */ 1572 M_ID_NOTE, /* id_note */ 1573 M_ID_NULL, /* id_null */ 1574 M_ID_PLT, /* id_plt */ 1575 M_ID_REL, /* id_rel */ 1576 M_ID_STRTAB, /* id_strtab */ 1577 M_ID_SYMINFO, /* id_syminfo */ 1578 M_ID_SYMTAB, /* id_symtab */ 1579 M_ID_SYMTAB_NDX, /* id_symtab_ndx */ 1580 M_ID_TEXT, /* id_text */ 1581 M_ID_TLS, /* id_tls */ 1582 M_ID_TLSBSS, /* id_tlsbss */ 1583 M_ID_UNKNOWN, /* id_unknown */ 1584 M_ID_UNWIND, /* id_unwind */ 1585 M_ID_UNWINDHDR, /* id_unwindhdr */ 1586 M_ID_USER, /* id_user */ 1587 M_ID_VERSION, /* id_version */ 1588 }, 1589 { /* Target_nullfunc */ 1590 nullfunc_tmpl, /* nf_template */ 1591 sizeof (nullfunc_tmpl), /* nf_size */ 1592 }, 1593 { /* Target_machrel */ 1594 reloc_table, 1595 1596 ld_init_rel, /* mr_init_rel */ 1597 ld_mach_eflags, /* mr_mach_eflags */ 1598 ld_mach_make_dynamic, /* mr_mach_make_dynamic */ 1599 ld_mach_update_odynamic, /* mr_mach_update_odynamic */ 1600 ld_calc_plt_addr, /* mr_calc_plt_addr */ 1601 ld_perform_outreloc, /* mr_perform_outreloc */ 1602 ld_do_activerelocs, /* mr_do_activerelocs */ 1603 ld_add_outrel, /* mr_add_outrel */ 1604 NULL, /* mr_reloc_register */ 1605 ld_reloc_local, /* mr_reloc_local */ 1606 NULL, /* mr_reloc_GOTOP */ 1607 ld_reloc_TLS, /* mr_reloc_TLS */ 1608 NULL, /* mr_assign_got */ 1609 ld_find_got_ndx, /* mr_find_got_ndx */ 1610 ld_calc_got_offset, /* mr_calc_got_offset */ 1611 ld_assign_got_ndx, /* mr_assign_got_ndx */ 1612 ld_assign_plt_ndx, /* mr_assign_plt_ndx */ 1613 NULL, /* mr_allocate_got */ 1614 ld_fillin_gotplt, /* mr_fillin_gotplt */ 1615 }, 1616 { /* Target_machsym */ 1617 NULL, /* ms_reg_check */ 1618 NULL, /* ms_mach_sym_typecheck */ 1619 NULL, /* ms_is_regsym */ 1620 NULL, /* ms_reg_find */ 1621 NULL /* ms_reg_enter */ 1622 } 1623 }; 1624 1625 return (&_ld_targ); 1626 } 1627