1 /* x86 specific support for ELF 2 Copyright (C) 2017-2021 Free Software Foundation, Inc. 3 4 This file is part of BFD, the Binary File Descriptor library. 5 6 This program is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 3 of the License, or 9 (at your option) any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program; if not, write to the Free Software 18 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 19 MA 02110-1301, USA. */ 20 21 /* Don't generate unused section symbols. */ 22 #define TARGET_KEEP_UNUSED_SECTION_SYMBOLS false 23 24 #include "sysdep.h" 25 #include "bfd.h" 26 #include "bfdlink.h" 27 #include "libbfd.h" 28 #include "elf-bfd.h" 29 #include "hashtab.h" 30 #include "elf-linker-x86.h" 31 32 #define PLT_CIE_LENGTH 20 33 #define PLT_FDE_LENGTH 36 34 #define PLT_FDE_START_OFFSET 4 + PLT_CIE_LENGTH + 8 35 #define PLT_FDE_LEN_OFFSET 4 + PLT_CIE_LENGTH + 12 36 37 #define ABI_64_P(abfd) \ 38 (get_elf_backend_data (abfd)->s->elfclass == ELFCLASS64) 39 40 /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid 41 copying dynamic variables from a shared lib into an app's dynbss 42 section, and instead use a dynamic relocation to point into the 43 shared lib. */ 44 #define ELIMINATE_COPY_RELOCS 1 45 46 #define elf_x86_hash_table(p, id) \ 47 (is_elf_hash_table ((p)->hash) \ 48 && elf_hash_table_id ((struct elf_link_hash_table *) ((p)->hash)) == (id) \ 49 ? ((struct elf_x86_link_hash_table *) ((p)->hash)) : NULL) 50 51 /* Will references to this symbol always be local in this object? */ 52 #define SYMBOL_REFERENCES_LOCAL_P(INFO, H) \ 53 _bfd_x86_elf_link_symbol_references_local ((INFO), (H)) 54 55 /* TRUE if an undefined weak symbol should be resolved to 0. Local 56 undefined weak symbol is always resolved to 0. Reference to an 57 undefined weak symbol is resolved to 0 in executable if undefined 58 weak symbol should be resolved to 0 (zero_undefweak > 0). */ 59 #define UNDEFINED_WEAK_RESOLVED_TO_ZERO(INFO, EH) \ 60 ((EH)->elf.root.type == bfd_link_hash_undefweak \ 61 && (SYMBOL_REFERENCES_LOCAL_P ((INFO), &(EH)->elf) \ 62 || (bfd_link_executable (INFO) \ 63 && (EH)->zero_undefweak > 0))) 64 65 /* Should copy relocation be generated for a symbol. Don't generate 66 copy relocation against a protected symbol defined in a shared 67 object with GNU_PROPERTY_NO_COPY_ON_PROTECTED. */ 68 #define SYMBOL_NO_COPYRELOC(INFO, EH) \ 69 ((EH)->def_protected \ 70 && ((EH)->elf.root.type == bfd_link_hash_defined \ 71 || (EH)->elf.root.type == bfd_link_hash_defweak) \ 72 && elf_has_no_copy_on_protected ((EH)->elf.root.u.def.section->owner) \ 73 && ((EH)->elf.root.u.def.section->owner->flags & DYNAMIC) != 0 \ 74 && ((EH)->elf.root.u.def.section->flags & SEC_CODE) == 0) 75 76 /* TRUE if dynamic relocation is needed. If we are creating a shared 77 library, and this is a reloc against a global symbol, or a non PC 78 relative reloc against a local symbol, then we need to copy the reloc 79 into the shared library. However, if we are linking with -Bsymbolic, 80 we do not need to copy a reloc against a global symbol which is 81 defined in an object we are including in the link (i.e., DEF_REGULAR 82 is set). 83 84 If PCREL_PLT is true, don't generate dynamic relocation in PIE for 85 PC-relative relocation against a dynamic function definition in data 86 section when PLT address can be used. 87 88 If on the other hand, we are creating an executable, we may need to 89 keep relocations for symbols satisfied by a dynamic library if we 90 manage to avoid copy relocs for the symbol. 91 92 We also need to generate dynamic pointer relocation against 93 STT_GNU_IFUNC symbol in the non-code section. */ 94 #define NEED_DYNAMIC_RELOCATION_P(INFO, PCREL_PLT, H, SEC, R_TYPE, \ 95 POINTER_TYPE) \ 96 ((bfd_link_pic (INFO) \ 97 && (! X86_PCREL_TYPE_P (R_TYPE) \ 98 || ((H) != NULL \ 99 && (! (bfd_link_pie (INFO) \ 100 || SYMBOLIC_BIND ((INFO), (H))) \ 101 || (H)->root.type == bfd_link_hash_defweak \ 102 || (!(bfd_link_pie (INFO) \ 103 && (PCREL_PLT) \ 104 && (H)->plt.refcount > 0 \ 105 && ((SEC)->flags & SEC_CODE) == 0 \ 106 && (H)->type == STT_FUNC \ 107 && (H)->def_dynamic) \ 108 && !(H)->def_regular))))) \ 109 || ((H) != NULL \ 110 && (H)->type == STT_GNU_IFUNC \ 111 && (R_TYPE) == POINTER_TYPE \ 112 && ((SEC)->flags & SEC_CODE) == 0) \ 113 || (ELIMINATE_COPY_RELOCS \ 114 && !bfd_link_pic (INFO) \ 115 && (H) != NULL \ 116 && ((H)->root.type == bfd_link_hash_defweak \ 117 || !(H)->def_regular))) 118 119 /* TRUE if dynamic relocation should be generated. Don't copy a 120 pc-relative relocation into the output file if the symbol needs 121 copy reloc or the symbol is undefined when building executable. 122 Copy dynamic function pointer relocations. Don't generate dynamic 123 relocations against resolved undefined weak symbols in PIE, except 124 when PC32_RELOC is TRUE. Undefined weak symbol is bound locally 125 when PIC is false. Don't generate dynamic relocations against 126 non-preemptible absolute symbol. */ 127 #define GENERATE_DYNAMIC_RELOCATION_P(INFO, EH, R_TYPE, SEC, \ 128 NEED_COPY_RELOC_IN_PIE, \ 129 RESOLVED_TO_ZERO, PC32_RELOC) \ 130 ((bfd_link_pic (INFO) \ 131 && !(bfd_is_abs_section (SEC) \ 132 && ((EH) == NULL \ 133 || SYMBOL_REFERENCES_LOCAL (INFO, &(EH)->elf))) \ 134 && !(NEED_COPY_RELOC_IN_PIE) \ 135 && ((EH) == NULL \ 136 || ((ELF_ST_VISIBILITY ((EH)->elf.other) == STV_DEFAULT \ 137 && (!(RESOLVED_TO_ZERO) || PC32_RELOC)) \ 138 || (EH)->elf.root.type != bfd_link_hash_undefweak)) \ 139 && ((!X86_PCREL_TYPE_P (R_TYPE) && !X86_SIZE_TYPE_P (R_TYPE)) \ 140 || ! SYMBOL_CALLS_LOCAL ((INFO), \ 141 (struct elf_link_hash_entry *) (EH)))) \ 142 || (ELIMINATE_COPY_RELOCS \ 143 && !bfd_link_pic (INFO) \ 144 && (EH) != NULL \ 145 && (EH)->elf.dynindx != -1 \ 146 && (!(EH)->elf.non_got_ref \ 147 || ((EH)->elf.root.type == bfd_link_hash_undefweak \ 148 && !(RESOLVED_TO_ZERO))) \ 149 && (((EH)->elf.def_dynamic && !(EH)->elf.def_regular) \ 150 || (EH)->elf.root.type == bfd_link_hash_undefined))) 151 152 /* TRUE if this input relocation should be copied to output. H->dynindx 153 may be -1 if this symbol was marked to become local. */ 154 #define COPY_INPUT_RELOC_P(INFO, H, R_TYPE) \ 155 ((H) != NULL \ 156 && (H)->dynindx != -1 \ 157 && (X86_PCREL_TYPE_P (R_TYPE) \ 158 || !(bfd_link_executable (INFO) || SYMBOLIC_BIND ((INFO), (H))) \ 159 || !(H)->def_regular)) 160 161 /* TRUE if this is actually a static link, or it is a -Bsymbolic link 162 and the symbol is defined locally, or the symbol was forced to be 163 local because of a version file. */ 164 #define RESOLVED_LOCALLY_P(INFO, H, HTAB) \ 165 (!WILL_CALL_FINISH_DYNAMIC_SYMBOL ((HTAB)->elf.dynamic_sections_created, \ 166 bfd_link_pic (INFO), (H)) \ 167 || (bfd_link_pic (INFO) \ 168 && SYMBOL_REFERENCES_LOCAL_P ((INFO), (H))) \ 169 || (ELF_ST_VISIBILITY ((H)->other) \ 170 && (H)->root.type == bfd_link_hash_undefweak)) 171 172 /* TRUE if this symbol isn't defined by a shared object. */ 173 #define SYMBOL_DEFINED_NON_SHARED_P(H) \ 174 ((H)->def_regular \ 175 || (H)->root.linker_def \ 176 || (H)->root.ldscript_def \ 177 || ((struct elf_x86_link_hash_entry *) (H))->linker_def \ 178 || ELF_COMMON_DEF_P (H)) 179 180 /* Return TRUE if the symbol described by a linker hash entry H is 181 going to be absolute. Similar to bfd_is_abs_symbol, but excluding 182 all linker-script defined symbols. */ 183 #define ABS_SYMBOL_P(H) \ 184 (bfd_is_abs_symbol (&(H)->root) && !(H)->root.ldscript_def) 185 186 /* TRUE if relative relocation should be generated. GOT reference to 187 global symbol in PIC will lead to dynamic symbol. It becomes a 188 problem when "time" or "times" is defined as a variable in an 189 executable, clashing with functions of the same name in libc. If a 190 symbol isn't undefined weak symbol, don't make it dynamic in PIC and 191 generate relative relocation. Don't generate relative relocation 192 against non-preemptible absolute symbol. */ 193 #define GENERATE_RELATIVE_RELOC_P(INFO, H) \ 194 ((H)->dynindx == -1 \ 195 && !(H)->forced_local \ 196 && (H)->root.type != bfd_link_hash_undefweak \ 197 && bfd_link_pic (INFO) \ 198 && !ABS_SYMBOL_P (H)) 199 200 /* TRUE if this is a pointer reference to a local IFUNC. */ 201 #define POINTER_LOCAL_IFUNC_P(INFO, H) \ 202 ((H)->dynindx == -1 \ 203 || (H)->forced_local \ 204 || bfd_link_executable (INFO)) 205 206 /* TRUE if this is a PLT reference to a local IFUNC. */ 207 #define PLT_LOCAL_IFUNC_P(INFO, H) \ 208 ((H)->dynindx == -1 \ 209 || ((bfd_link_executable (INFO) \ 210 || ELF_ST_VISIBILITY ((H)->other) != STV_DEFAULT) \ 211 && (H)->def_regular \ 212 && (H)->type == STT_GNU_IFUNC)) 213 214 /* TRUE if TLS IE->LE transition is OK. */ 215 #define TLS_TRANSITION_IE_TO_LE_P(INFO, H, TLS_TYPE) \ 216 (bfd_link_executable (INFO) \ 217 && (H) != NULL \ 218 && (H)->dynindx == -1 \ 219 && (TLS_TYPE & GOT_TLS_IE)) 220 221 /* Verify that the symbol has an entry in the procedure linkage table. */ 222 #define VERIFY_PLT_ENTRY(INFO, H, PLT, GOTPLT, RELPLT, LOCAL_UNDEFWEAK) \ 223 do \ 224 { \ 225 if (((H)->dynindx == -1 \ 226 && !LOCAL_UNDEFWEAK \ 227 && !(((H)->forced_local || bfd_link_executable (INFO)) \ 228 && (H)->def_regular \ 229 && (H)->type == STT_GNU_IFUNC)) \ 230 || (PLT) == NULL \ 231 || (GOTPLT) == NULL \ 232 || (RELPLT) == NULL) \ 233 abort (); \ 234 } \ 235 while (0); 236 237 /* Verify that the symbol supports copy relocation. */ 238 #define VERIFY_COPY_RELOC(H, HTAB) \ 239 do \ 240 { \ 241 if ((H)->dynindx == -1 \ 242 || ((H)->root.type != bfd_link_hash_defined \ 243 && (H)->root.type != bfd_link_hash_defweak) \ 244 || (HTAB)->elf.srelbss == NULL \ 245 || (HTAB)->elf.sreldynrelro == NULL) \ 246 abort (); \ 247 } \ 248 while (0); 249 250 /* x86 ELF linker hash entry. */ 251 252 struct elf_x86_link_hash_entry 253 { 254 struct elf_link_hash_entry elf; 255 256 unsigned char tls_type; 257 258 /* Bit 0: Symbol has no GOT nor PLT relocations. 259 Bit 1: Symbol has non-GOT/non-PLT relocations in text sections. 260 zero_undefweak is initialized to 1 and undefined weak symbol 261 should be resolved to 0 if zero_undefweak > 0. */ 262 unsigned int zero_undefweak : 2; 263 264 /* Don't call finish_dynamic_symbol on this symbol. */ 265 unsigned int no_finish_dynamic_symbol : 1; 266 267 /* TRUE if symbol is __tls_get_addr. */ 268 unsigned int tls_get_addr : 1; 269 270 /* TRUE if symbol is defined as a protected symbol. */ 271 unsigned int def_protected : 1; 272 273 /* 0: Symbol references are unknown. 274 1: Symbol references aren't local. 275 2: Symbol references are local. 276 */ 277 unsigned int local_ref : 2; 278 279 /* TRUE if symbol is defined by linker. */ 280 unsigned int linker_def : 1; 281 282 /* TRUE if symbol is referenced by R_386_GOTOFF relocation. This is 283 only used by i386. */ 284 unsigned int gotoff_ref : 1; 285 286 /* TRUE if a weak symbol with a real definition needs a copy reloc. 287 When there is a weak symbol with a real definition, the processor 288 independent code will have arranged for us to see the real 289 definition first. We need to copy the needs_copy bit from the 290 real definition and check it when allowing copy reloc in PIE. This 291 is only used by x86-64. */ 292 unsigned int needs_copy : 1; 293 294 /* Information about the GOT PLT entry. Filled when there are both 295 GOT and PLT relocations against the same function. */ 296 union gotplt_union plt_got; 297 298 /* Information about the second PLT entry. */ 299 union gotplt_union plt_second; 300 301 /* Offset of the GOTPLT entry reserved for the TLS descriptor, 302 starting at the end of the jump table. */ 303 bfd_vma tlsdesc_got; 304 }; 305 306 struct elf_x86_lazy_plt_layout 307 { 308 /* The first entry in a lazy procedure linkage table looks like this. */ 309 const bfd_byte *plt0_entry; 310 unsigned int plt0_entry_size; /* Size of PLT0 entry. */ 311 312 /* Later entries in a lazy procedure linkage table look like this. */ 313 const bfd_byte *plt_entry; 314 unsigned int plt_entry_size; /* Size of each PLT entry. */ 315 316 /* The TLSDESC entry in a lazy procedure linkage table looks like 317 this. This is for x86-64 only. */ 318 const bfd_byte *plt_tlsdesc_entry; 319 unsigned int plt_tlsdesc_entry_size; /* Size of TLSDESC entry. */ 320 321 /* Offsets into the TLSDESC entry that are to be replaced with 322 GOT+8 and GOT+TDG. These are for x86-64 only. */ 323 unsigned int plt_tlsdesc_got1_offset; 324 unsigned int plt_tlsdesc_got2_offset; 325 326 /* Offset of the end of the PC-relative instructions containing 327 plt_tlsdesc_got1_offset and plt_tlsdesc_got2_offset. These 328 are for x86-64 only. */ 329 unsigned int plt_tlsdesc_got1_insn_end; 330 unsigned int plt_tlsdesc_got2_insn_end; 331 332 /* Offsets into plt0_entry that are to be replaced with GOT[1] and 333 GOT[2]. */ 334 unsigned int plt0_got1_offset; 335 unsigned int plt0_got2_offset; 336 337 /* Offset of the end of the PC-relative instruction containing 338 plt0_got2_offset. This is for x86-64 only. */ 339 unsigned int plt0_got2_insn_end; 340 341 /* Offsets into plt_entry that are to be replaced with... */ 342 unsigned int plt_got_offset; /* ... address of this symbol in .got. */ 343 unsigned int plt_reloc_offset; /* ... offset into relocation table. */ 344 unsigned int plt_plt_offset; /* ... offset to start of .plt. */ 345 346 /* Length of the PC-relative instruction containing plt_got_offset. 347 This is used for x86-64 only. */ 348 unsigned int plt_got_insn_size; 349 350 /* Offset of the end of the PC-relative jump to plt0_entry. This is 351 used for x86-64 only. */ 352 unsigned int plt_plt_insn_end; 353 354 /* Offset into plt_entry where the initial value of the GOT entry 355 points. */ 356 unsigned int plt_lazy_offset; 357 358 /* The first entry in a PIC lazy procedure linkage table looks like 359 this. */ 360 const bfd_byte *pic_plt0_entry; 361 362 /* Subsequent entries in a PIC lazy procedure linkage table look 363 like this. */ 364 const bfd_byte *pic_plt_entry; 365 366 /* .eh_frame covering the lazy .plt section. */ 367 const bfd_byte *eh_frame_plt; 368 unsigned int eh_frame_plt_size; 369 }; 370 371 struct elf_x86_non_lazy_plt_layout 372 { 373 /* Entries in a non-lazy procedure linkage table look like this. */ 374 const bfd_byte *plt_entry; 375 /* Entries in a PIC non-lazy procedure linkage table look like this. 376 This is only used for i386 where absolute PLT and PIC PLT are 377 different. */ 378 const bfd_byte *pic_plt_entry; 379 380 unsigned int plt_entry_size; /* Size of each PLT entry. */ 381 382 /* Offsets into plt_entry that are to be replaced with... */ 383 unsigned int plt_got_offset; /* ... address of this symbol in .got. */ 384 385 /* Length of the PC-relative instruction containing plt_got_offset. 386 This is used for x86-64 only. */ 387 unsigned int plt_got_insn_size; 388 389 /* .eh_frame covering the non-lazy .plt section. */ 390 const bfd_byte *eh_frame_plt; 391 unsigned int eh_frame_plt_size; 392 }; 393 394 struct elf_x86_plt_layout 395 { 396 /* The first entry in a lazy procedure linkage table looks like this. */ 397 const bfd_byte *plt0_entry; 398 /* Entries in a procedure linkage table look like this. */ 399 const bfd_byte *plt_entry; 400 unsigned int plt_entry_size; /* Size of each PLT entry. */ 401 402 /* 1 has PLT0. */ 403 unsigned int has_plt0; 404 405 /* Offsets into plt_entry that are to be replaced with... */ 406 unsigned int plt_got_offset; /* ... address of this symbol in .got. */ 407 408 /* Length of the PC-relative instruction containing plt_got_offset. 409 This is only used for x86-64. */ 410 unsigned int plt_got_insn_size; 411 412 /* Alignment of the .iplt section. */ 413 unsigned int iplt_alignment; 414 415 /* .eh_frame covering the .plt section. */ 416 const bfd_byte *eh_frame_plt; 417 unsigned int eh_frame_plt_size; 418 }; 419 420 /* Values in tls_type of x86 ELF linker hash entry. */ 421 #define GOT_UNKNOWN 0 422 #define GOT_NORMAL 1 423 #define GOT_TLS_GD 2 424 #define GOT_TLS_IE 4 425 #define GOT_TLS_IE_POS 5 426 #define GOT_TLS_IE_NEG 6 427 #define GOT_TLS_IE_BOTH 7 428 #define GOT_TLS_GDESC 8 429 #define GOT_ABS 9 430 #define GOT_TLS_GD_BOTH_P(type) \ 431 ((type) == (GOT_TLS_GD | GOT_TLS_GDESC)) 432 #define GOT_TLS_GD_P(type) \ 433 ((type) == GOT_TLS_GD || GOT_TLS_GD_BOTH_P (type)) 434 #define GOT_TLS_GDESC_P(type) \ 435 ((type) == GOT_TLS_GDESC || GOT_TLS_GD_BOTH_P (type)) 436 #define GOT_TLS_GD_ANY_P(type) \ 437 (GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type)) 438 439 #define elf_x86_hash_entry(ent) \ 440 ((struct elf_x86_link_hash_entry *)(ent)) 441 442 /* x86 ELF linker hash table. */ 443 444 struct elf_x86_link_hash_table 445 { 446 struct elf_link_hash_table elf; 447 448 /* Short-cuts to get to dynamic linker sections. */ 449 asection *interp; 450 asection *plt_eh_frame; 451 asection *plt_second; 452 asection *plt_second_eh_frame; 453 asection *plt_got; 454 asection *plt_got_eh_frame; 455 456 /* Parameters describing PLT generation, lazy or non-lazy. */ 457 struct elf_x86_plt_layout plt; 458 459 /* Parameters describing lazy PLT generation. */ 460 const struct elf_x86_lazy_plt_layout *lazy_plt; 461 462 /* Parameters describing non-lazy PLT generation. */ 463 const struct elf_x86_non_lazy_plt_layout *non_lazy_plt; 464 465 union 466 { 467 bfd_signed_vma refcount; 468 bfd_vma offset; 469 } tls_ld_or_ldm_got; 470 471 /* The amount of space used by the jump slots in the GOT. */ 472 bfd_vma sgotplt_jump_table_size; 473 474 /* _TLS_MODULE_BASE_ symbol. */ 475 struct bfd_link_hash_entry *tls_module_base; 476 477 /* Used by local STT_GNU_IFUNC symbols. */ 478 htab_t loc_hash_table; 479 void * loc_hash_memory; 480 481 /* The index of the next R_X86_64_JUMP_SLOT entry in .rela.plt. */ 482 bfd_vma next_jump_slot_index; 483 /* The index of the next R_X86_64_IRELATIVE entry in .rela.plt. */ 484 bfd_vma next_irelative_index; 485 486 /* The (unloaded but important) .rel.plt.unloaded section on VxWorks. 487 This is used for i386 only. */ 488 asection *srelplt2; 489 490 /* The index of the next unused R_386_TLS_DESC slot in .rel.plt. This 491 is only used for i386. */ 492 bfd_vma next_tls_desc_index; 493 494 /* Value used to fill the unused bytes of the first PLT entry. This 495 is only used for i386. */ 496 bfd_byte plt0_pad_byte; 497 498 /* TRUE if GOT is referenced. */ 499 unsigned int got_referenced : 1; 500 501 /* TRUE if PLT is PC-relative. PLT in PDE and PC-relative PLT in PIE 502 can be used as function address. 503 504 NB: i386 has non-PIC PLT and PIC PLT. Only non-PIC PLT in PDE can 505 be used as function address. PIC PLT in PIE can't be used as 506 function address. */ 507 unsigned int pcrel_plt : 1; 508 509 bfd_vma (*r_info) (bfd_vma, bfd_vma); 510 bfd_vma (*r_sym) (bfd_vma); 511 bool (*is_reloc_section) (const char *); 512 unsigned int sizeof_reloc; 513 unsigned int got_entry_size; 514 unsigned int pointer_r_type; 515 int dynamic_interpreter_size; 516 const char *dynamic_interpreter; 517 const char *tls_get_addr; 518 519 /* Options passed from the linker. */ 520 struct elf_linker_x86_params *params; 521 }; 522 523 struct elf_x86_init_table 524 { 525 /* The lazy PLT layout. */ 526 const struct elf_x86_lazy_plt_layout *lazy_plt; 527 528 /* The non-lazy PLT layout. */ 529 const struct elf_x86_non_lazy_plt_layout *non_lazy_plt; 530 531 /* The lazy PLT layout for IBT. */ 532 const struct elf_x86_lazy_plt_layout *lazy_ibt_plt; 533 534 /* The non-lazy PLT layout for IBT. */ 535 const struct elf_x86_non_lazy_plt_layout *non_lazy_ibt_plt; 536 537 bfd_byte plt0_pad_byte; 538 539 bfd_vma (*r_info) (bfd_vma, bfd_vma); 540 bfd_vma (*r_sym) (bfd_vma); 541 }; 542 543 struct elf_x86_obj_tdata 544 { 545 struct elf_obj_tdata root; 546 547 /* tls_type for each local got entry. */ 548 char *local_got_tls_type; 549 550 /* GOTPLT entries for TLS descriptors. */ 551 bfd_vma *local_tlsdesc_gotent; 552 }; 553 554 enum elf_x86_plt_type 555 { 556 plt_non_lazy = 0, 557 plt_lazy = 1 << 0, 558 plt_pic = 1 << 1, 559 plt_second = 1 << 2, 560 plt_unknown = -1 561 }; 562 563 struct elf_x86_plt 564 { 565 const char *name; 566 asection *sec; 567 bfd_byte *contents; 568 enum elf_x86_plt_type type; 569 unsigned int plt_got_offset; 570 unsigned int plt_entry_size; 571 unsigned int plt_got_insn_size; /* Only used for x86-64. */ 572 long count; 573 }; 574 575 /* Set if a relocation is converted from a GOTPCREL relocation. */ 576 #define R_X86_64_converted_reloc_bit (1 << 7) 577 578 #define elf_x86_tdata(abfd) \ 579 ((struct elf_x86_obj_tdata *) (abfd)->tdata.any) 580 581 #define elf_x86_local_got_tls_type(abfd) \ 582 (elf_x86_tdata (abfd)->local_got_tls_type) 583 584 #define elf_x86_local_tlsdesc_gotent(abfd) \ 585 (elf_x86_tdata (abfd)->local_tlsdesc_gotent) 586 587 #define elf_x86_compute_jump_table_size(htab) \ 588 ((htab)->elf.srelplt->reloc_count * (htab)->got_entry_size) 589 590 #define is_x86_elf(bfd, htab) \ 591 (bfd_get_flavour (bfd) == bfd_target_elf_flavour \ 592 && elf_tdata (bfd) != NULL \ 593 && elf_object_id (bfd) == (htab)->elf.hash_table_id) 594 595 extern bool _bfd_x86_elf_mkobject 596 (bfd *); 597 598 extern void _bfd_x86_elf_set_tls_module_base 599 (struct bfd_link_info *); 600 601 extern bfd_vma _bfd_x86_elf_dtpoff_base 602 (struct bfd_link_info *); 603 604 extern bool _bfd_x86_elf_readonly_dynrelocs 605 (struct elf_link_hash_entry *, void *); 606 607 extern struct elf_link_hash_entry * _bfd_elf_x86_get_local_sym_hash 608 (struct elf_x86_link_hash_table *, bfd *, const Elf_Internal_Rela *, 609 bool); 610 611 extern hashval_t _bfd_x86_elf_local_htab_hash 612 (const void *); 613 614 extern int _bfd_x86_elf_local_htab_eq 615 (const void *, const void *); 616 617 extern struct bfd_hash_entry * _bfd_x86_elf_link_hash_newfunc 618 (struct bfd_hash_entry *, struct bfd_hash_table *, const char *); 619 620 extern struct bfd_link_hash_table * _bfd_x86_elf_link_hash_table_create 621 (bfd *); 622 623 extern int _bfd_x86_elf_compare_relocs 624 (const void *, const void *); 625 626 extern bool _bfd_x86_elf_link_check_relocs 627 (bfd *, struct bfd_link_info *); 628 629 extern bool _bfd_elf_x86_valid_reloc_p 630 (asection *, struct bfd_link_info *, struct elf_x86_link_hash_table *, 631 const Elf_Internal_Rela *, struct elf_link_hash_entry *, 632 Elf_Internal_Sym *, Elf_Internal_Shdr *, bool *); 633 634 extern bool _bfd_x86_elf_size_dynamic_sections 635 (bfd *, struct bfd_link_info *); 636 637 extern struct elf_x86_link_hash_table *_bfd_x86_elf_finish_dynamic_sections 638 (bfd *, struct bfd_link_info *); 639 640 extern bool _bfd_x86_elf_always_size_sections 641 (bfd *, struct bfd_link_info *); 642 643 extern void _bfd_x86_elf_merge_symbol_attribute 644 (struct elf_link_hash_entry *, unsigned int, bool, bool); 645 646 extern void _bfd_x86_elf_copy_indirect_symbol 647 (struct bfd_link_info *, struct elf_link_hash_entry *, 648 struct elf_link_hash_entry *); 649 650 extern bool _bfd_x86_elf_fixup_symbol 651 (struct bfd_link_info *, struct elf_link_hash_entry *); 652 653 extern bool _bfd_x86_elf_hash_symbol 654 (struct elf_link_hash_entry *); 655 656 extern bool _bfd_x86_elf_adjust_dynamic_symbol 657 (struct bfd_link_info *, struct elf_link_hash_entry *); 658 659 extern void _bfd_x86_elf_hide_symbol 660 (struct bfd_link_info *, struct elf_link_hash_entry *, bool); 661 662 extern bool _bfd_x86_elf_link_symbol_references_local 663 (struct bfd_link_info *, struct elf_link_hash_entry *); 664 665 extern asection * _bfd_x86_elf_gc_mark_hook 666 (asection *, struct bfd_link_info *, Elf_Internal_Rela *, 667 struct elf_link_hash_entry *, Elf_Internal_Sym *); 668 669 extern long _bfd_x86_elf_get_synthetic_symtab 670 (bfd *, long, long, bfd_vma, struct elf_x86_plt [], asymbol **, 671 asymbol **); 672 673 extern enum elf_property_kind _bfd_x86_elf_parse_gnu_properties 674 (bfd *, unsigned int, bfd_byte *, unsigned int); 675 676 extern bool _bfd_x86_elf_merge_gnu_properties 677 (struct bfd_link_info *, bfd *, bfd *, elf_property *, elf_property *); 678 679 extern void _bfd_x86_elf_link_fixup_gnu_properties 680 (struct bfd_link_info *, elf_property_list **); 681 682 extern bfd * _bfd_x86_elf_link_setup_gnu_properties 683 (struct bfd_link_info *, struct elf_x86_init_table *); 684 685 extern void _bfd_x86_elf_link_fixup_ifunc_symbol 686 (struct bfd_link_info *, struct elf_x86_link_hash_table *, 687 struct elf_link_hash_entry *, Elf_Internal_Sym *sym); 688 689 extern void _bfd_x86_elf_link_report_relative_reloc 690 (struct bfd_link_info *, asection *, struct elf_link_hash_entry *, 691 Elf_Internal_Sym *, const char *, const void *); 692 693 #define bfd_elf64_mkobject \ 694 _bfd_x86_elf_mkobject 695 #define bfd_elf32_mkobject \ 696 _bfd_x86_elf_mkobject 697 #define bfd_elf64_bfd_link_hash_table_create \ 698 _bfd_x86_elf_link_hash_table_create 699 #define bfd_elf32_bfd_link_hash_table_create \ 700 _bfd_x86_elf_link_hash_table_create 701 #define bfd_elf64_bfd_link_check_relocs \ 702 _bfd_x86_elf_link_check_relocs 703 #define bfd_elf32_bfd_link_check_relocs \ 704 _bfd_x86_elf_link_check_relocs 705 706 #define elf_backend_size_dynamic_sections \ 707 _bfd_x86_elf_size_dynamic_sections 708 #define elf_backend_always_size_sections \ 709 _bfd_x86_elf_always_size_sections 710 #define elf_backend_merge_symbol_attribute \ 711 _bfd_x86_elf_merge_symbol_attribute 712 #define elf_backend_copy_indirect_symbol \ 713 _bfd_x86_elf_copy_indirect_symbol 714 #define elf_backend_fixup_symbol \ 715 _bfd_x86_elf_fixup_symbol 716 #define elf_backend_hash_symbol \ 717 _bfd_x86_elf_hash_symbol 718 #define elf_backend_adjust_dynamic_symbol \ 719 _bfd_x86_elf_adjust_dynamic_symbol 720 #define elf_backend_gc_mark_hook \ 721 _bfd_x86_elf_gc_mark_hook 722 #define elf_backend_omit_section_dynsym \ 723 _bfd_elf_omit_section_dynsym_all 724 #define elf_backend_parse_gnu_properties \ 725 _bfd_x86_elf_parse_gnu_properties 726 #define elf_backend_merge_gnu_properties \ 727 _bfd_x86_elf_merge_gnu_properties 728 #define elf_backend_fixup_gnu_properties \ 729 _bfd_x86_elf_link_fixup_gnu_properties 730