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 2010 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_ACT, 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_ACT, 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_IS_STATIC_EXEC(ofl)) 1067 return (1); 1068 1069 /* 1070 * Obtain the new available relocation cache entry. 1071 */ 1072 if ((rcp = ld_add_rel_cache(ofl, &ofl->ofl_outrels, &nextsize, 1073 REL_LOIDESCNO, REL_HOIDESCNO)) == (Rel_cache *)S_ERROR) 1074 return (S_ERROR); 1075 1076 orsp = rcp->rc_free; 1077 1078 /* 1079 * If we are adding a output relocation against a section 1080 * symbol (non-RELATIVE) then mark that section. These sections 1081 * will be added to the .dynsym symbol table. 1082 */ 1083 if (sdp && (rsp->rel_rtype != M_R_RELATIVE) && 1084 ((flags & FLG_REL_SCNNDX) || 1085 (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION))) { 1086 1087 /* 1088 * If this is a COMMON symbol - no output section 1089 * exists yet - (it's created as part of sym_validate()). 1090 * So - we mark here that when it's created it should 1091 * be tagged with the FLG_OS_OUTREL flag. 1092 */ 1093 if ((sdp->sd_flags & FLG_SY_SPECSEC) && 1094 (sdp->sd_sym->st_shndx == SHN_COMMON)) { 1095 if (ELF_ST_TYPE(sdp->sd_sym->st_info) != STT_TLS) 1096 ofl->ofl_flags1 |= FLG_OF1_BSSOREL; 1097 else 1098 ofl->ofl_flags1 |= FLG_OF1_TLSOREL; 1099 } else { 1100 Os_desc *osp = sdp->sd_isc->is_osdesc; 1101 1102 if (osp && ((osp->os_flags & FLG_OS_OUTREL) == 0)) { 1103 ofl->ofl_dynshdrcnt++; 1104 osp->os_flags |= FLG_OS_OUTREL; 1105 } 1106 } 1107 } 1108 1109 *orsp = *rsp; 1110 orsp->rel_flags |= flags; 1111 1112 rcp->rc_free++; 1113 ofl->ofl_outrelscnt++; 1114 1115 if (flags & FLG_REL_GOT) 1116 ofl->ofl_relocgotsz += (Xword)sizeof (Rela); 1117 else if (flags & FLG_REL_PLT) 1118 ofl->ofl_relocpltsz += (Xword)sizeof (Rela); 1119 else if (flags & FLG_REL_BSS) 1120 ofl->ofl_relocbsssz += (Xword)sizeof (Rela); 1121 else if (flags & FLG_REL_NOINFO) 1122 ofl->ofl_relocrelsz += (Xword)sizeof (Rela); 1123 else 1124 orsp->rel_osdesc->os_szoutrels += (Xword)sizeof (Rela); 1125 1126 if (orsp->rel_rtype == M_R_RELATIVE) 1127 ofl->ofl_relocrelcnt++; 1128 1129 /* 1130 * We don't perform sorting on PLT relocations because 1131 * they have already been assigned a PLT index and if we 1132 * were to sort them we would have to re-assign the plt indexes. 1133 */ 1134 if (!(flags & FLG_REL_PLT)) 1135 ofl->ofl_reloccnt++; 1136 1137 /* 1138 * Insure a GLOBAL_OFFSET_TABLE is generated if required. 1139 */ 1140 if (IS_GOT_REQUIRED(orsp->rel_rtype)) 1141 ofl->ofl_flags |= FLG_OF_BLDGOT; 1142 1143 /* 1144 * Identify and possibly warn of a displacement relocation. 1145 */ 1146 if (orsp->rel_flags & FLG_REL_DISP) { 1147 ofl->ofl_dtflags_1 |= DF_1_DISPRELPND; 1148 1149 if (ofl->ofl_flags & FLG_OF_VERBOSE) 1150 ld_disp_errmsg(MSG_INTL(MSG_REL_DISPREL4), orsp, ofl); 1151 } 1152 DBG_CALL(Dbg_reloc_ors_entry(ofl->ofl_lml, ELF_DBG_LD, SHT_RELA, 1153 M_MACH, orsp)); 1154 return (1); 1155 } 1156 1157 /* 1158 * process relocation for a LOCAL symbol 1159 */ 1160 static uintptr_t 1161 ld_reloc_local(Rel_desc * rsp, Ofl_desc * ofl) 1162 { 1163 ofl_flag_t flags = ofl->ofl_flags; 1164 Sym_desc *sdp = rsp->rel_sym; 1165 Word shndx = sdp->sd_sym->st_shndx; 1166 Word ortype = rsp->rel_rtype; 1167 1168 /* 1169 * if ((shared object) and (not pc relative relocation) and 1170 * (not against ABS symbol)) 1171 * then 1172 * build R_AMD64_RELATIVE 1173 * fi 1174 */ 1175 if ((flags & FLG_OF_SHAROBJ) && (rsp->rel_flags & FLG_REL_LOAD) && 1176 !(IS_PC_RELATIVE(rsp->rel_rtype)) && !(IS_SIZE(rsp->rel_rtype)) && 1177 !(IS_GOT_BASED(rsp->rel_rtype)) && 1178 !(rsp->rel_isdesc != NULL && 1179 (rsp->rel_isdesc->is_shdr->sh_type == SHT_SUNW_dof)) && 1180 (((sdp->sd_flags & FLG_SY_SPECSEC) == 0) || 1181 (shndx != SHN_ABS) || (sdp->sd_aux && sdp->sd_aux->sa_symspec))) { 1182 1183 /* 1184 * R_AMD64_RELATIVE updates a 64bit address, if this 1185 * relocation isn't a 64bit binding then we can not 1186 * simplify it to a RELATIVE relocation. 1187 */ 1188 if (reloc_table[ortype].re_fsize != sizeof (Addr)) { 1189 return (ld_add_outrel(0, rsp, ofl)); 1190 } 1191 1192 rsp->rel_rtype = R_AMD64_RELATIVE; 1193 if (ld_add_outrel(FLG_REL_ADVAL, rsp, ofl) == S_ERROR) 1194 return (S_ERROR); 1195 rsp->rel_rtype = ortype; 1196 return (1); 1197 } 1198 1199 /* 1200 * If the relocation is against a 'non-allocatable' section 1201 * and we can not resolve it now - then give a warning 1202 * message. 1203 * 1204 * We can not resolve the symbol if either: 1205 * a) it's undefined 1206 * b) it's defined in a shared library and a 1207 * COPY relocation hasn't moved it to the executable 1208 * 1209 * Note: because we process all of the relocations against the 1210 * text segment before any others - we know whether 1211 * or not a copy relocation will be generated before 1212 * we get here (see reloc_init()->reloc_segments()). 1213 */ 1214 if (!(rsp->rel_flags & FLG_REL_LOAD) && 1215 ((shndx == SHN_UNDEF) || 1216 ((sdp->sd_ref == REF_DYN_NEED) && 1217 ((sdp->sd_flags & FLG_SY_MVTOCOMM) == 0)))) { 1218 Conv_inv_buf_t inv_buf; 1219 1220 /* 1221 * If the relocation is against a SHT_SUNW_ANNOTATE 1222 * section - then silently ignore that the relocation 1223 * can not be resolved. 1224 */ 1225 if (rsp->rel_osdesc && 1226 (rsp->rel_osdesc->os_shdr->sh_type == SHT_SUNW_ANNOTATE)) 1227 return (0); 1228 (void) eprintf(ofl->ofl_lml, ERR_WARNING, 1229 MSG_INTL(MSG_REL_EXTERNSYM), 1230 conv_reloc_amd64_type(rsp->rel_rtype, 0, &inv_buf), 1231 rsp->rel_isdesc->is_file->ifl_name, 1232 demangle(rsp->rel_sname), rsp->rel_osdesc->os_name); 1233 return (1); 1234 } 1235 1236 /* 1237 * Perform relocation. 1238 */ 1239 return (ld_add_actrel(NULL, rsp, ofl)); 1240 } 1241 1242 1243 static uintptr_t 1244 ld_reloc_TLS(Boolean local, Rel_desc * rsp, Ofl_desc * ofl) 1245 { 1246 Word rtype = rsp->rel_rtype; 1247 Sym_desc *sdp = rsp->rel_sym; 1248 ofl_flag_t flags = ofl->ofl_flags; 1249 Gotndx *gnp; 1250 1251 /* 1252 * If we're building an executable - use either the IE or LE access 1253 * model. If we're building a shared object process any IE model. 1254 */ 1255 if ((flags & FLG_OF_EXEC) || (IS_TLS_IE(rtype))) { 1256 /* 1257 * Set the DF_STATIC_TLS flag. 1258 */ 1259 ofl->ofl_dtflags |= DF_STATIC_TLS; 1260 1261 if (!local || ((flags & FLG_OF_EXEC) == 0)) { 1262 /* 1263 * Assign a GOT entry for static TLS references. 1264 */ 1265 if ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs, 1266 GOT_REF_TLSIE, ofl, rsp)) == NULL) { 1267 1268 if (ld_assign_got_TLS(local, rsp, ofl, sdp, 1269 gnp, GOT_REF_TLSIE, FLG_REL_STLS, 1270 rtype, R_AMD64_TPOFF64, 0) == S_ERROR) 1271 return (S_ERROR); 1272 } 1273 1274 /* 1275 * IE access model. 1276 */ 1277 if (IS_TLS_IE(rtype)) 1278 return (ld_add_actrel(FLG_REL_STLS, rsp, ofl)); 1279 1280 /* 1281 * Fixups are required for other executable models. 1282 */ 1283 return (ld_add_actrel((FLG_REL_TLSFIX | FLG_REL_STLS), 1284 rsp, ofl)); 1285 } 1286 1287 /* 1288 * LE access model. 1289 */ 1290 if (IS_TLS_LE(rtype)) 1291 return (ld_add_actrel(FLG_REL_STLS, rsp, ofl)); 1292 1293 return (ld_add_actrel((FLG_REL_TLSFIX | FLG_REL_STLS), 1294 rsp, ofl)); 1295 } 1296 1297 /* 1298 * Building a shared object. 1299 * 1300 * Assign a GOT entry for a dynamic TLS reference. 1301 */ 1302 if (IS_TLS_LD(rtype) && ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs, 1303 GOT_REF_TLSLD, ofl, rsp)) == NULL)) { 1304 1305 if (ld_assign_got_TLS(local, rsp, ofl, sdp, gnp, GOT_REF_TLSLD, 1306 FLG_REL_MTLS, rtype, R_AMD64_DTPMOD64, NULL) == S_ERROR) 1307 return (S_ERROR); 1308 1309 } else if (IS_TLS_GD(rtype) && 1310 ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs, GOT_REF_TLSGD, 1311 ofl, rsp)) == NULL)) { 1312 1313 if (ld_assign_got_TLS(local, rsp, ofl, sdp, gnp, GOT_REF_TLSGD, 1314 FLG_REL_DTLS, rtype, R_AMD64_DTPMOD64, 1315 R_AMD64_DTPOFF64) == S_ERROR) 1316 return (S_ERROR); 1317 } 1318 1319 if (IS_TLS_LD(rtype)) 1320 return (ld_add_actrel(FLG_REL_MTLS, rsp, ofl)); 1321 1322 return (ld_add_actrel(FLG_REL_DTLS, rsp, ofl)); 1323 } 1324 1325 /* ARGSUSED5 */ 1326 static uintptr_t 1327 ld_assign_got_ndx(Alist **alpp, Gotndx *pgnp, Gotref gref, Ofl_desc *ofl, 1328 Rel_desc *rsp, Sym_desc *sdp) 1329 { 1330 Xword raddend; 1331 Gotndx gn, *gnp; 1332 Aliste idx; 1333 uint_t gotents; 1334 1335 raddend = rsp->rel_raddend; 1336 if (pgnp && (pgnp->gn_addend == raddend) && (pgnp->gn_gotref == gref)) 1337 return (1); 1338 1339 if ((gref == GOT_REF_TLSGD) || (gref == GOT_REF_TLSLD)) 1340 gotents = 2; 1341 else 1342 gotents = 1; 1343 1344 gn.gn_addend = raddend; 1345 gn.gn_gotndx = ofl->ofl_gotcnt; 1346 gn.gn_gotref = gref; 1347 1348 ofl->ofl_gotcnt += gotents; 1349 1350 if (gref == GOT_REF_TLSLD) { 1351 if (ofl->ofl_tlsldgotndx == NULL) { 1352 if ((gnp = libld_malloc(sizeof (Gotndx))) == NULL) 1353 return (S_ERROR); 1354 (void) memcpy(gnp, &gn, sizeof (Gotndx)); 1355 ofl->ofl_tlsldgotndx = gnp; 1356 } 1357 return (1); 1358 } 1359 1360 idx = 0; 1361 for (ALIST_TRAVERSE(*alpp, idx, gnp)) { 1362 if (gnp->gn_addend > raddend) 1363 break; 1364 } 1365 1366 /* 1367 * GOT indexes are maintained on an Alist, where there is typically 1368 * only one index. The usage of this list is to scan the list to find 1369 * an index, and then apply that index immediately to a relocation. 1370 * Thus there are no external references to these GOT index structures 1371 * that can be compromised by the Alist being reallocated. 1372 */ 1373 if (alist_insert(alpp, &gn, sizeof (Gotndx), 1374 AL_CNT_SDP_GOT, idx) == NULL) 1375 return (S_ERROR); 1376 1377 return (1); 1378 } 1379 1380 static void 1381 ld_assign_plt_ndx(Sym_desc * sdp, Ofl_desc *ofl) 1382 { 1383 sdp->sd_aux->sa_PLTndx = 1 + ofl->ofl_pltcnt++; 1384 sdp->sd_aux->sa_PLTGOTndx = ofl->ofl_gotcnt++; 1385 ofl->ofl_flags |= FLG_OF_BLDGOT; 1386 } 1387 1388 static uchar_t plt0_template[M_PLT_ENTSIZE] = { 1389 /* 0x00 PUSHQ GOT+8(%rip) */ 0xff, 0x35, 0x00, 0x00, 0x00, 0x00, 1390 /* 0x06 JMP *GOT+16(%rip) */ 0xff, 0x25, 0x00, 0x00, 0x00, 0x00, 1391 /* 0x0c NOP */ 0x90, 1392 /* 0x0d NOP */ 0x90, 1393 /* 0x0e NOP */ 0x90, 1394 /* 0x0f NOP */ 0x90 1395 }; 1396 1397 /* 1398 * Initializes .got[0] with the _DYNAMIC symbol value. 1399 */ 1400 static uintptr_t 1401 ld_fillin_gotplt(Ofl_desc *ofl) 1402 { 1403 int bswap = (ofl->ofl_flags1 & FLG_OF1_ENCDIFF) != 0; 1404 1405 if (ofl->ofl_osgot) { 1406 Sym_desc *sdp; 1407 1408 if ((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_DYNAMIC_U), 1409 SYM_NOHASH, NULL, ofl)) != NULL) { 1410 uchar_t *genptr; 1411 1412 genptr = ((uchar_t *)ofl->ofl_osgot->os_outdata->d_buf + 1413 (M_GOT_XDYNAMIC * M_GOT_ENTSIZE)); 1414 /* LINTED */ 1415 *(Xword *)genptr = sdp->sd_sym->st_value; 1416 if (bswap) 1417 /* LINTED */ 1418 *(Xword *)genptr = 1419 /* LINTED */ 1420 ld_bswap_Xword(*(Xword *)genptr); 1421 } 1422 } 1423 1424 /* 1425 * Fill in the reserved slot in the procedure linkage table the first 1426 * entry is: 1427 * 0x00 PUSHQ GOT+8(%rip) # GOT[1] 1428 * 0x06 JMP *GOT+16(%rip) # GOT[2] 1429 * 0x0c NOP 1430 * 0x0d NOP 1431 * 0x0e NOP 1432 * 0x0f NOP 1433 */ 1434 if ((ofl->ofl_flags & FLG_OF_DYNAMIC) && ofl->ofl_osplt) { 1435 uchar_t *pltent; 1436 Xword val1; 1437 1438 pltent = (uchar_t *)ofl->ofl_osplt->os_outdata->d_buf; 1439 bcopy(plt0_template, pltent, sizeof (plt0_template)); 1440 1441 /* 1442 * If '-z noreloc' is specified - skip the do_reloc_ld 1443 * stage. 1444 */ 1445 if (!OFL_DO_RELOC(ofl)) 1446 return (1); 1447 1448 /* 1449 * filin: 1450 * PUSHQ GOT + 8(%rip) 1451 * 1452 * Note: 0x06 below represents the offset to the 1453 * next instruction - which is what %rip will 1454 * be pointing at. 1455 */ 1456 val1 = (ofl->ofl_osgot->os_shdr->sh_addr) + 1457 (M_GOT_XLINKMAP * M_GOT_ENTSIZE) - 1458 ofl->ofl_osplt->os_shdr->sh_addr - 0x06; 1459 1460 if (do_reloc_ld(R_AMD64_GOTPCREL, &pltent[0x02], 1461 &val1, MSG_ORIG(MSG_SYM_PLTENT), 1462 MSG_ORIG(MSG_SPECFIL_PLTENT), bswap, ofl->ofl_lml) == 0) { 1463 eprintf(ofl->ofl_lml, ERR_FATAL, 1464 MSG_INTL(MSG_PLT_PLT0FAIL)); 1465 return (S_ERROR); 1466 } 1467 1468 /* 1469 * filin: 1470 * JMP *GOT+16(%rip) 1471 */ 1472 val1 = (ofl->ofl_osgot->os_shdr->sh_addr) + 1473 (M_GOT_XRTLD * M_GOT_ENTSIZE) - 1474 ofl->ofl_osplt->os_shdr->sh_addr - 0x0c; 1475 1476 if (do_reloc_ld(R_AMD64_GOTPCREL, &pltent[0x08], 1477 &val1, MSG_ORIG(MSG_SYM_PLTENT), 1478 MSG_ORIG(MSG_SPECFIL_PLTENT), bswap, ofl->ofl_lml) == 0) { 1479 eprintf(ofl->ofl_lml, ERR_FATAL, 1480 MSG_INTL(MSG_PLT_PLT0FAIL)); 1481 return (S_ERROR); 1482 } 1483 } 1484 1485 return (1); 1486 } 1487 1488 1489 1490 /* 1491 * Template for generating "void (*)(void)" function 1492 */ 1493 static const uchar_t nullfunc_tmpl[] = { /* amd64 */ 1494 /* 0x00 */ 0x55, /* pushq %rbp */ 1495 /* 0x01 */ 0x48, 0x8b, 0xec, /* movq %rsp,%rbp */ 1496 /* 0x04 */ 0x48, 0x8b, 0xe5, /* movq %rbp,%rsp */ 1497 /* 0x07 */ 0x5d, /* popq %rbp */ 1498 /* 0x08 */ 0xc3 /* ret */ 1499 }; 1500 1501 1502 /* 1503 * Function used to provide fill padding in SHF_EXECINSTR sections 1504 * 1505 * entry: 1506 * 1507 * base - base address of section being filled 1508 * offset - starting offset for fill within memory referenced by base 1509 * cnt - # bytes to be filled 1510 * 1511 * exit: 1512 * The fill has been completed. 1513 */ 1514 static void 1515 execfill(void *base, off_t off, size_t cnt) 1516 { 1517 /* 1518 * 0x90 is an X86 NOP instruction in both 32 and 64-bit worlds. 1519 * There are no alignment constraints. 1520 */ 1521 (void) memset(off + (char *)base, 0x90, cnt); 1522 } 1523 1524 1525 /* 1526 * Return the ld_targ definition for this target. 1527 */ 1528 const Target * 1529 ld_targ_init_x86(void) 1530 { 1531 static const Target _ld_targ = { 1532 { /* Target_mach */ 1533 M_MACH, /* m_mach */ 1534 M_MACHPLUS, /* m_machplus */ 1535 M_FLAGSPLUS, /* m_flagsplus */ 1536 M_CLASS, /* m_class */ 1537 M_DATA, /* m_data */ 1538 1539 M_SEGM_ALIGN, /* m_segm_align */ 1540 M_SEGM_ORIGIN, /* m_segm_origin */ 1541 M_SEGM_AORIGIN, /* m_segm_aorigin */ 1542 M_DATASEG_PERM, /* m_dataseg_perm */ 1543 M_STACK_PERM, /* m_stack_perm */ 1544 M_WORD_ALIGN, /* m_word_align */ 1545 MSG_ORIG(MSG_PTH_RTLD_AMD64), /* m_def_interp */ 1546 1547 /* Relocation type codes */ 1548 M_R_ARRAYADDR, /* m_r_arrayaddr */ 1549 M_R_COPY, /* m_r_copy */ 1550 M_R_GLOB_DAT, /* m_r_glob_dat */ 1551 M_R_JMP_SLOT, /* m_r_jmp_slot */ 1552 M_R_NUM, /* m_r_num */ 1553 M_R_NONE, /* m_r_none */ 1554 M_R_RELATIVE, /* m_r_relative */ 1555 M_R_REGISTER, /* m_r_register */ 1556 1557 /* Relocation related constants */ 1558 M_REL_DT_COUNT, /* m_rel_dt_count */ 1559 M_REL_DT_ENT, /* m_rel_dt_ent */ 1560 M_REL_DT_SIZE, /* m_rel_dt_size */ 1561 M_REL_DT_TYPE, /* m_rel_dt_type */ 1562 M_REL_SHT_TYPE, /* m_rel_sht_type */ 1563 1564 /* GOT related constants */ 1565 M_GOT_ENTSIZE, /* m_got_entsize */ 1566 M_GOT_XNumber, /* m_got_xnumber */ 1567 1568 /* PLT related constants */ 1569 M_PLT_ALIGN, /* m_plt_align */ 1570 M_PLT_ENTSIZE, /* m_plt_entsize */ 1571 M_PLT_RESERVSZ, /* m_plt_reservsz */ 1572 M_PLT_SHF_FLAGS, /* m_plt_shf_flags */ 1573 1574 /* Section type of .eh_frame/.eh_frame_hdr sections */ 1575 SHT_AMD64_UNWIND, /* m_sht_unwind */ 1576 1577 M_DT_REGISTER, /* m_dt_register */ 1578 }, 1579 { /* Target_machid */ 1580 M_ID_ARRAY, /* id_array */ 1581 M_ID_BSS, /* id_bss */ 1582 M_ID_CAP, /* id_cap */ 1583 M_ID_DATA, /* id_data */ 1584 M_ID_DYNAMIC, /* id_dynamic */ 1585 M_ID_DYNSORT, /* id_dynsort */ 1586 M_ID_DYNSTR, /* id_dynstr */ 1587 M_ID_DYNSYM, /* id_dynsym */ 1588 M_ID_DYNSYM_NDX, /* id_dynsym_ndx */ 1589 M_ID_GOT, /* id_got */ 1590 M_ID_UNKNOWN, /* id_gotdata (unused) */ 1591 M_ID_HASH, /* id_hash */ 1592 M_ID_INTERP, /* id_interp */ 1593 M_ID_LBSS, /* id_lbss */ 1594 M_ID_LDYNSYM, /* id_ldynsym */ 1595 M_ID_NOTE, /* id_note */ 1596 M_ID_NULL, /* id_null */ 1597 M_ID_PLT, /* id_plt */ 1598 M_ID_REL, /* id_rel */ 1599 M_ID_STRTAB, /* id_strtab */ 1600 M_ID_SYMINFO, /* id_syminfo */ 1601 M_ID_SYMTAB, /* id_symtab */ 1602 M_ID_SYMTAB_NDX, /* id_symtab_ndx */ 1603 M_ID_TEXT, /* id_text */ 1604 M_ID_TLS, /* id_tls */ 1605 M_ID_TLSBSS, /* id_tlsbss */ 1606 M_ID_UNKNOWN, /* id_unknown */ 1607 M_ID_UNWIND, /* id_unwind */ 1608 M_ID_UNWINDHDR, /* id_unwindhdr */ 1609 M_ID_USER, /* id_user */ 1610 M_ID_VERSION, /* id_version */ 1611 }, 1612 { /* Target_nullfunc */ 1613 nullfunc_tmpl, /* nf_template */ 1614 sizeof (nullfunc_tmpl), /* nf_size */ 1615 }, 1616 { /* Target_fillfunc */ 1617 execfill /* ff_execfill */ 1618 }, 1619 { /* Target_machrel */ 1620 reloc_table, 1621 1622 ld_init_rel, /* mr_init_rel */ 1623 ld_mach_eflags, /* mr_mach_eflags */ 1624 ld_mach_make_dynamic, /* mr_mach_make_dynamic */ 1625 ld_mach_update_odynamic, /* mr_mach_update_odynamic */ 1626 ld_calc_plt_addr, /* mr_calc_plt_addr */ 1627 ld_perform_outreloc, /* mr_perform_outreloc */ 1628 ld_do_activerelocs, /* mr_do_activerelocs */ 1629 ld_add_outrel, /* mr_add_outrel */ 1630 NULL, /* mr_reloc_register */ 1631 ld_reloc_local, /* mr_reloc_local */ 1632 NULL, /* mr_reloc_GOTOP */ 1633 ld_reloc_TLS, /* mr_reloc_TLS */ 1634 NULL, /* mr_assign_got */ 1635 ld_find_got_ndx, /* mr_find_got_ndx */ 1636 ld_calc_got_offset, /* mr_calc_got_offset */ 1637 ld_assign_got_ndx, /* mr_assign_got_ndx */ 1638 ld_assign_plt_ndx, /* mr_assign_plt_ndx */ 1639 NULL, /* mr_allocate_got */ 1640 ld_fillin_gotplt, /* mr_fillin_gotplt */ 1641 }, 1642 { /* Target_machsym */ 1643 NULL, /* ms_reg_check */ 1644 NULL, /* ms_mach_sym_typecheck */ 1645 NULL, /* ms_is_regsym */ 1646 NULL, /* ms_reg_find */ 1647 NULL /* ms_reg_enter */ 1648 } 1649 }; 1650 1651 return (&_ld_targ); 1652 } 1653