1/* X86-64 specific support for 64-bit ELF 2 Copyright 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 3 Free Software Foundation, Inc. 4 Contributed by Jan Hubicka <jh@suse.cz>. 5 6 This file is part of BFD, the Binary File Descriptor library. 7 8 This program is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 3 of the License, or 11 (at your option) any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with this program; if not, write to the Free Software 20 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 21 MA 02110-1301, USA. */ 22 23#include "sysdep.h" 24#include "bfd.h" 25#include "bfdlink.h" 26#include "libbfd.h" 27#include "elf-bfd.h" 28#include "bfd_stdint.h" 29 30#include "elf/x86-64.h" 31 32/* In case we're on a 32-bit machine, construct a 64-bit "-1" value. */ 33#define MINUS_ONE (~ (bfd_vma) 0) 34 35/* The relocation "howto" table. Order of fields: 36 type, rightshift, size, bitsize, pc_relative, bitpos, complain_on_overflow, 37 special_function, name, partial_inplace, src_mask, dst_mask, pcrel_offset. */ 38static reloc_howto_type x86_64_elf_howto_table[] = 39{ 40 HOWTO(R_X86_64_NONE, 0, 0, 0, FALSE, 0, complain_overflow_dont, 41 bfd_elf_generic_reloc, "R_X86_64_NONE", FALSE, 0x00000000, 0x00000000, 42 FALSE), 43 HOWTO(R_X86_64_64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield, 44 bfd_elf_generic_reloc, "R_X86_64_64", FALSE, MINUS_ONE, MINUS_ONE, 45 FALSE), 46 HOWTO(R_X86_64_PC32, 0, 2, 32, TRUE, 0, complain_overflow_signed, 47 bfd_elf_generic_reloc, "R_X86_64_PC32", FALSE, 0xffffffff, 0xffffffff, 48 TRUE), 49 HOWTO(R_X86_64_GOT32, 0, 2, 32, FALSE, 0, complain_overflow_signed, 50 bfd_elf_generic_reloc, "R_X86_64_GOT32", FALSE, 0xffffffff, 0xffffffff, 51 FALSE), 52 HOWTO(R_X86_64_PLT32, 0, 2, 32, TRUE, 0, complain_overflow_signed, 53 bfd_elf_generic_reloc, "R_X86_64_PLT32", FALSE, 0xffffffff, 0xffffffff, 54 TRUE), 55 HOWTO(R_X86_64_COPY, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 56 bfd_elf_generic_reloc, "R_X86_64_COPY", FALSE, 0xffffffff, 0xffffffff, 57 FALSE), 58 HOWTO(R_X86_64_GLOB_DAT, 0, 4, 64, FALSE, 0, complain_overflow_bitfield, 59 bfd_elf_generic_reloc, "R_X86_64_GLOB_DAT", FALSE, MINUS_ONE, 60 MINUS_ONE, FALSE), 61 HOWTO(R_X86_64_JUMP_SLOT, 0, 4, 64, FALSE, 0, complain_overflow_bitfield, 62 bfd_elf_generic_reloc, "R_X86_64_JUMP_SLOT", FALSE, MINUS_ONE, 63 MINUS_ONE, FALSE), 64 HOWTO(R_X86_64_RELATIVE, 0, 4, 64, FALSE, 0, complain_overflow_bitfield, 65 bfd_elf_generic_reloc, "R_X86_64_RELATIVE", FALSE, MINUS_ONE, 66 MINUS_ONE, FALSE), 67 HOWTO(R_X86_64_GOTPCREL, 0, 2, 32, TRUE, 0, complain_overflow_signed, 68 bfd_elf_generic_reloc, "R_X86_64_GOTPCREL", FALSE, 0xffffffff, 69 0xffffffff, TRUE), 70 HOWTO(R_X86_64_32, 0, 2, 32, FALSE, 0, complain_overflow_unsigned, 71 bfd_elf_generic_reloc, "R_X86_64_32", FALSE, 0xffffffff, 0xffffffff, 72 FALSE), 73 HOWTO(R_X86_64_32S, 0, 2, 32, FALSE, 0, complain_overflow_signed, 74 bfd_elf_generic_reloc, "R_X86_64_32S", FALSE, 0xffffffff, 0xffffffff, 75 FALSE), 76 HOWTO(R_X86_64_16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield, 77 bfd_elf_generic_reloc, "R_X86_64_16", FALSE, 0xffff, 0xffff, FALSE), 78 HOWTO(R_X86_64_PC16,0, 1, 16, TRUE, 0, complain_overflow_bitfield, 79 bfd_elf_generic_reloc, "R_X86_64_PC16", FALSE, 0xffff, 0xffff, TRUE), 80 HOWTO(R_X86_64_8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield, 81 bfd_elf_generic_reloc, "R_X86_64_8", FALSE, 0xff, 0xff, FALSE), 82 HOWTO(R_X86_64_PC8, 0, 0, 8, TRUE, 0, complain_overflow_signed, 83 bfd_elf_generic_reloc, "R_X86_64_PC8", FALSE, 0xff, 0xff, TRUE), 84 HOWTO(R_X86_64_DTPMOD64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield, 85 bfd_elf_generic_reloc, "R_X86_64_DTPMOD64", FALSE, MINUS_ONE, 86 MINUS_ONE, FALSE), 87 HOWTO(R_X86_64_DTPOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield, 88 bfd_elf_generic_reloc, "R_X86_64_DTPOFF64", FALSE, MINUS_ONE, 89 MINUS_ONE, FALSE), 90 HOWTO(R_X86_64_TPOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield, 91 bfd_elf_generic_reloc, "R_X86_64_TPOFF64", FALSE, MINUS_ONE, 92 MINUS_ONE, FALSE), 93 HOWTO(R_X86_64_TLSGD, 0, 2, 32, TRUE, 0, complain_overflow_signed, 94 bfd_elf_generic_reloc, "R_X86_64_TLSGD", FALSE, 0xffffffff, 95 0xffffffff, TRUE), 96 HOWTO(R_X86_64_TLSLD, 0, 2, 32, TRUE, 0, complain_overflow_signed, 97 bfd_elf_generic_reloc, "R_X86_64_TLSLD", FALSE, 0xffffffff, 98 0xffffffff, TRUE), 99 HOWTO(R_X86_64_DTPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed, 100 bfd_elf_generic_reloc, "R_X86_64_DTPOFF32", FALSE, 0xffffffff, 101 0xffffffff, FALSE), 102 HOWTO(R_X86_64_GOTTPOFF, 0, 2, 32, TRUE, 0, complain_overflow_signed, 103 bfd_elf_generic_reloc, "R_X86_64_GOTTPOFF", FALSE, 0xffffffff, 104 0xffffffff, TRUE), 105 HOWTO(R_X86_64_TPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed, 106 bfd_elf_generic_reloc, "R_X86_64_TPOFF32", FALSE, 0xffffffff, 107 0xffffffff, FALSE), 108 HOWTO(R_X86_64_PC64, 0, 4, 64, TRUE, 0, complain_overflow_bitfield, 109 bfd_elf_generic_reloc, "R_X86_64_PC64", FALSE, MINUS_ONE, MINUS_ONE, 110 TRUE), 111 HOWTO(R_X86_64_GOTOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield, 112 bfd_elf_generic_reloc, "R_X86_64_GOTOFF64", 113 FALSE, MINUS_ONE, MINUS_ONE, FALSE), 114 HOWTO(R_X86_64_GOTPC32, 0, 2, 32, TRUE, 0, complain_overflow_signed, 115 bfd_elf_generic_reloc, "R_X86_64_GOTPC32", 116 FALSE, 0xffffffff, 0xffffffff, TRUE), 117 HOWTO(R_X86_64_GOT64, 0, 4, 64, FALSE, 0, complain_overflow_signed, 118 bfd_elf_generic_reloc, "R_X86_64_GOT64", FALSE, MINUS_ONE, MINUS_ONE, 119 FALSE), 120 HOWTO(R_X86_64_GOTPCREL64, 0, 4, 64, TRUE, 0, complain_overflow_signed, 121 bfd_elf_generic_reloc, "R_X86_64_GOTPCREL64", FALSE, MINUS_ONE, 122 MINUS_ONE, TRUE), 123 HOWTO(R_X86_64_GOTPC64, 0, 4, 64, TRUE, 0, complain_overflow_signed, 124 bfd_elf_generic_reloc, "R_X86_64_GOTPC64", 125 FALSE, MINUS_ONE, MINUS_ONE, TRUE), 126 HOWTO(R_X86_64_GOTPLT64, 0, 4, 64, FALSE, 0, complain_overflow_signed, 127 bfd_elf_generic_reloc, "R_X86_64_GOTPLT64", FALSE, MINUS_ONE, 128 MINUS_ONE, FALSE), 129 HOWTO(R_X86_64_PLTOFF64, 0, 4, 64, FALSE, 0, complain_overflow_signed, 130 bfd_elf_generic_reloc, "R_X86_64_PLTOFF64", FALSE, MINUS_ONE, 131 MINUS_ONE, FALSE), 132 EMPTY_HOWTO (32), 133 EMPTY_HOWTO (33), 134 HOWTO(R_X86_64_GOTPC32_TLSDESC, 0, 2, 32, TRUE, 0, 135 complain_overflow_bitfield, bfd_elf_generic_reloc, 136 "R_X86_64_GOTPC32_TLSDESC", 137 FALSE, 0xffffffff, 0xffffffff, TRUE), 138 HOWTO(R_X86_64_TLSDESC_CALL, 0, 0, 0, FALSE, 0, 139 complain_overflow_dont, bfd_elf_generic_reloc, 140 "R_X86_64_TLSDESC_CALL", 141 FALSE, 0, 0, FALSE), 142 HOWTO(R_X86_64_TLSDESC, 0, 4, 64, FALSE, 0, 143 complain_overflow_bitfield, bfd_elf_generic_reloc, 144 "R_X86_64_TLSDESC", 145 FALSE, MINUS_ONE, MINUS_ONE, FALSE), 146 147 /* We have a gap in the reloc numbers here. 148 R_X86_64_standard counts the number up to this point, and 149 R_X86_64_vt_offset is the value to subtract from a reloc type of 150 R_X86_64_GNU_VT* to form an index into this table. */ 151#define R_X86_64_standard (R_X86_64_TLSDESC + 1) 152#define R_X86_64_vt_offset (R_X86_64_GNU_VTINHERIT - R_X86_64_standard) 153 154/* GNU extension to record C++ vtable hierarchy. */ 155 HOWTO (R_X86_64_GNU_VTINHERIT, 0, 4, 0, FALSE, 0, complain_overflow_dont, 156 NULL, "R_X86_64_GNU_VTINHERIT", FALSE, 0, 0, FALSE), 157 158/* GNU extension to record C++ vtable member usage. */ 159 HOWTO (R_X86_64_GNU_VTENTRY, 0, 4, 0, FALSE, 0, complain_overflow_dont, 160 _bfd_elf_rel_vtable_reloc_fn, "R_X86_64_GNU_VTENTRY", FALSE, 0, 0, 161 FALSE) 162}; 163 164/* Map BFD relocs to the x86_64 elf relocs. */ 165struct elf_reloc_map 166{ 167 bfd_reloc_code_real_type bfd_reloc_val; 168 unsigned char elf_reloc_val; 169}; 170 171static const struct elf_reloc_map x86_64_reloc_map[] = 172{ 173 { BFD_RELOC_NONE, R_X86_64_NONE, }, 174 { BFD_RELOC_64, R_X86_64_64, }, 175 { BFD_RELOC_32_PCREL, R_X86_64_PC32, }, 176 { BFD_RELOC_X86_64_GOT32, R_X86_64_GOT32,}, 177 { BFD_RELOC_X86_64_PLT32, R_X86_64_PLT32,}, 178 { BFD_RELOC_X86_64_COPY, R_X86_64_COPY, }, 179 { BFD_RELOC_X86_64_GLOB_DAT, R_X86_64_GLOB_DAT, }, 180 { BFD_RELOC_X86_64_JUMP_SLOT, R_X86_64_JUMP_SLOT, }, 181 { BFD_RELOC_X86_64_RELATIVE, R_X86_64_RELATIVE, }, 182 { BFD_RELOC_X86_64_GOTPCREL, R_X86_64_GOTPCREL, }, 183 { BFD_RELOC_32, R_X86_64_32, }, 184 { BFD_RELOC_X86_64_32S, R_X86_64_32S, }, 185 { BFD_RELOC_16, R_X86_64_16, }, 186 { BFD_RELOC_16_PCREL, R_X86_64_PC16, }, 187 { BFD_RELOC_8, R_X86_64_8, }, 188 { BFD_RELOC_8_PCREL, R_X86_64_PC8, }, 189 { BFD_RELOC_X86_64_DTPMOD64, R_X86_64_DTPMOD64, }, 190 { BFD_RELOC_X86_64_DTPOFF64, R_X86_64_DTPOFF64, }, 191 { BFD_RELOC_X86_64_TPOFF64, R_X86_64_TPOFF64, }, 192 { BFD_RELOC_X86_64_TLSGD, R_X86_64_TLSGD, }, 193 { BFD_RELOC_X86_64_TLSLD, R_X86_64_TLSLD, }, 194 { BFD_RELOC_X86_64_DTPOFF32, R_X86_64_DTPOFF32, }, 195 { BFD_RELOC_X86_64_GOTTPOFF, R_X86_64_GOTTPOFF, }, 196 { BFD_RELOC_X86_64_TPOFF32, R_X86_64_TPOFF32, }, 197 { BFD_RELOC_64_PCREL, R_X86_64_PC64, }, 198 { BFD_RELOC_X86_64_GOTOFF64, R_X86_64_GOTOFF64, }, 199 { BFD_RELOC_X86_64_GOTPC32, R_X86_64_GOTPC32, }, 200 { BFD_RELOC_X86_64_GOT64, R_X86_64_GOT64, }, 201 { BFD_RELOC_X86_64_GOTPCREL64,R_X86_64_GOTPCREL64, }, 202 { BFD_RELOC_X86_64_GOTPC64, R_X86_64_GOTPC64, }, 203 { BFD_RELOC_X86_64_GOTPLT64, R_X86_64_GOTPLT64, }, 204 { BFD_RELOC_X86_64_PLTOFF64, R_X86_64_PLTOFF64, }, 205 { BFD_RELOC_X86_64_GOTPC32_TLSDESC, R_X86_64_GOTPC32_TLSDESC, }, 206 { BFD_RELOC_X86_64_TLSDESC_CALL, R_X86_64_TLSDESC_CALL, }, 207 { BFD_RELOC_X86_64_TLSDESC, R_X86_64_TLSDESC, }, 208 { BFD_RELOC_VTABLE_INHERIT, R_X86_64_GNU_VTINHERIT, }, 209 { BFD_RELOC_VTABLE_ENTRY, R_X86_64_GNU_VTENTRY, }, 210}; 211 212static reloc_howto_type * 213elf64_x86_64_rtype_to_howto (bfd *abfd, unsigned r_type) 214{ 215 unsigned i; 216 217 if (r_type < (unsigned int) R_X86_64_GNU_VTINHERIT 218 || r_type >= (unsigned int) R_X86_64_max) 219 { 220 if (r_type >= (unsigned int) R_X86_64_standard) 221 { 222 (*_bfd_error_handler) (_("%B: invalid relocation type %d"), 223 abfd, (int) r_type); 224 r_type = R_X86_64_NONE; 225 } 226 i = r_type; 227 } 228 else 229 i = r_type - (unsigned int) R_X86_64_vt_offset; 230 BFD_ASSERT (x86_64_elf_howto_table[i].type == r_type); 231 return &x86_64_elf_howto_table[i]; 232} 233 234/* Given a BFD reloc type, return a HOWTO structure. */ 235static reloc_howto_type * 236elf64_x86_64_reloc_type_lookup (bfd *abfd, 237 bfd_reloc_code_real_type code) 238{ 239 unsigned int i; 240 241 for (i = 0; i < sizeof (x86_64_reloc_map) / sizeof (struct elf_reloc_map); 242 i++) 243 { 244 if (x86_64_reloc_map[i].bfd_reloc_val == code) 245 return elf64_x86_64_rtype_to_howto (abfd, 246 x86_64_reloc_map[i].elf_reloc_val); 247 } 248 return 0; 249} 250 251static reloc_howto_type * 252elf64_x86_64_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED, 253 const char *r_name) 254{ 255 unsigned int i; 256 257 for (i = 0; 258 i < (sizeof (x86_64_elf_howto_table) 259 / sizeof (x86_64_elf_howto_table[0])); 260 i++) 261 if (x86_64_elf_howto_table[i].name != NULL 262 && strcasecmp (x86_64_elf_howto_table[i].name, r_name) == 0) 263 return &x86_64_elf_howto_table[i]; 264 265 return NULL; 266} 267 268/* Given an x86_64 ELF reloc type, fill in an arelent structure. */ 269 270static void 271elf64_x86_64_info_to_howto (bfd *abfd ATTRIBUTE_UNUSED, arelent *cache_ptr, 272 Elf_Internal_Rela *dst) 273{ 274 unsigned r_type; 275 276 r_type = ELF64_R_TYPE (dst->r_info); 277 cache_ptr->howto = elf64_x86_64_rtype_to_howto (abfd, r_type); 278 BFD_ASSERT (r_type == cache_ptr->howto->type); 279} 280 281/* Support for core dump NOTE sections. */ 282static bfd_boolean 283elf64_x86_64_grok_prstatus (bfd *abfd, Elf_Internal_Note *note) 284{ 285 int offset; 286 size_t size; 287 288 switch (note->descsz) 289 { 290 default: 291 return FALSE; 292 293 case 336: /* sizeof(istruct elf_prstatus) on Linux/x86_64 */ 294 /* pr_cursig */ 295 elf_tdata (abfd)->core_signal 296 = bfd_get_16 (abfd, note->descdata + 12); 297 298 /* pr_pid */ 299 elf_tdata (abfd)->core_pid 300 = bfd_get_32 (abfd, note->descdata + 32); 301 302 /* pr_reg */ 303 offset = 112; 304 size = 216; 305 306 break; 307 } 308 309 /* Make a ".reg/999" section. */ 310 return _bfd_elfcore_make_pseudosection (abfd, ".reg", 311 size, note->descpos + offset); 312} 313 314static bfd_boolean 315elf64_x86_64_grok_psinfo (bfd *abfd, Elf_Internal_Note *note) 316{ 317 switch (note->descsz) 318 { 319 default: 320 return FALSE; 321 322 case 136: /* sizeof(struct elf_prpsinfo) on Linux/x86_64 */ 323 elf_tdata (abfd)->core_program 324 = _bfd_elfcore_strndup (abfd, note->descdata + 40, 16); 325 elf_tdata (abfd)->core_command 326 = _bfd_elfcore_strndup (abfd, note->descdata + 56, 80); 327 } 328 329 /* Note that for some reason, a spurious space is tacked 330 onto the end of the args in some (at least one anyway) 331 implementations, so strip it off if it exists. */ 332 333 { 334 char *command = elf_tdata (abfd)->core_command; 335 int n = strlen (command); 336 337 if (0 < n && command[n - 1] == ' ') 338 command[n - 1] = '\0'; 339 } 340 341 return TRUE; 342} 343 344/* Functions for the x86-64 ELF linker. */ 345 346/* The name of the dynamic interpreter. This is put in the .interp 347 section. */ 348 349#define ELF_DYNAMIC_INTERPRETER "/lib/ld64.so.1" 350 351/* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid 352 copying dynamic variables from a shared lib into an app's dynbss 353 section, and instead use a dynamic relocation to point into the 354 shared lib. */ 355#define ELIMINATE_COPY_RELOCS 1 356 357/* The size in bytes of an entry in the global offset table. */ 358 359#define GOT_ENTRY_SIZE 8 360 361/* The size in bytes of an entry in the procedure linkage table. */ 362 363#define PLT_ENTRY_SIZE 16 364 365/* The first entry in a procedure linkage table looks like this. See the 366 SVR4 ABI i386 supplement and the x86-64 ABI to see how this works. */ 367 368static const bfd_byte elf64_x86_64_plt0_entry[PLT_ENTRY_SIZE] = 369{ 370 0xff, 0x35, 8, 0, 0, 0, /* pushq GOT+8(%rip) */ 371 0xff, 0x25, 16, 0, 0, 0, /* jmpq *GOT+16(%rip) */ 372 0x0f, 0x1f, 0x40, 0x00 /* nopl 0(%rax) */ 373}; 374 375/* Subsequent entries in a procedure linkage table look like this. */ 376 377static const bfd_byte elf64_x86_64_plt_entry[PLT_ENTRY_SIZE] = 378{ 379 0xff, 0x25, /* jmpq *name@GOTPC(%rip) */ 380 0, 0, 0, 0, /* replaced with offset to this symbol in .got. */ 381 0x68, /* pushq immediate */ 382 0, 0, 0, 0, /* replaced with index into relocation table. */ 383 0xe9, /* jmp relative */ 384 0, 0, 0, 0 /* replaced with offset to start of .plt0. */ 385}; 386 387/* The x86-64 linker needs to keep track of the number of relocs that 388 it decides to copy as dynamic relocs in check_relocs for each symbol. 389 This is so that it can later discard them if they are found to be 390 unnecessary. We store the information in a field extending the 391 regular ELF linker hash table. */ 392 393struct elf64_x86_64_dyn_relocs 394{ 395 /* Next section. */ 396 struct elf64_x86_64_dyn_relocs *next; 397 398 /* The input section of the reloc. */ 399 asection *sec; 400 401 /* Total number of relocs copied for the input section. */ 402 bfd_size_type count; 403 404 /* Number of pc-relative relocs copied for the input section. */ 405 bfd_size_type pc_count; 406}; 407 408/* x86-64 ELF linker hash entry. */ 409 410struct elf64_x86_64_link_hash_entry 411{ 412 struct elf_link_hash_entry elf; 413 414 /* Track dynamic relocs copied for this symbol. */ 415 struct elf64_x86_64_dyn_relocs *dyn_relocs; 416 417#define GOT_UNKNOWN 0 418#define GOT_NORMAL 1 419#define GOT_TLS_GD 2 420#define GOT_TLS_IE 3 421#define GOT_TLS_GDESC 4 422#define GOT_TLS_GD_BOTH_P(type) \ 423 ((type) == (GOT_TLS_GD | GOT_TLS_GDESC)) 424#define GOT_TLS_GD_P(type) \ 425 ((type) == GOT_TLS_GD || GOT_TLS_GD_BOTH_P (type)) 426#define GOT_TLS_GDESC_P(type) \ 427 ((type) == GOT_TLS_GDESC || GOT_TLS_GD_BOTH_P (type)) 428#define GOT_TLS_GD_ANY_P(type) \ 429 (GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type)) 430 unsigned char tls_type; 431 432 /* Offset of the GOTPLT entry reserved for the TLS descriptor, 433 starting at the end of the jump table. */ 434 bfd_vma tlsdesc_got; 435}; 436 437#define elf64_x86_64_hash_entry(ent) \ 438 ((struct elf64_x86_64_link_hash_entry *)(ent)) 439 440struct elf64_x86_64_obj_tdata 441{ 442 struct elf_obj_tdata root; 443 444 /* tls_type for each local got entry. */ 445 char *local_got_tls_type; 446 447 /* GOTPLT entries for TLS descriptors. */ 448 bfd_vma *local_tlsdesc_gotent; 449}; 450 451#define elf64_x86_64_tdata(abfd) \ 452 ((struct elf64_x86_64_obj_tdata *) (abfd)->tdata.any) 453 454#define elf64_x86_64_local_got_tls_type(abfd) \ 455 (elf64_x86_64_tdata (abfd)->local_got_tls_type) 456 457#define elf64_x86_64_local_tlsdesc_gotent(abfd) \ 458 (elf64_x86_64_tdata (abfd)->local_tlsdesc_gotent) 459 460/* x86-64 ELF linker hash table. */ 461 462struct elf64_x86_64_link_hash_table 463{ 464 struct elf_link_hash_table elf; 465 466 /* Short-cuts to get to dynamic linker sections. */ 467 asection *sgot; 468 asection *sgotplt; 469 asection *srelgot; 470 asection *splt; 471 asection *srelplt; 472 asection *sdynbss; 473 asection *srelbss; 474 475 /* The offset into splt of the PLT entry for the TLS descriptor 476 resolver. Special values are 0, if not necessary (or not found 477 to be necessary yet), and -1 if needed but not determined 478 yet. */ 479 bfd_vma tlsdesc_plt; 480 /* The offset into sgot of the GOT entry used by the PLT entry 481 above. */ 482 bfd_vma tlsdesc_got; 483 484 union { 485 bfd_signed_vma refcount; 486 bfd_vma offset; 487 } tls_ld_got; 488 489 /* The amount of space used by the jump slots in the GOT. */ 490 bfd_vma sgotplt_jump_table_size; 491 492 /* Small local sym to section mapping cache. */ 493 struct sym_sec_cache sym_sec; 494}; 495 496/* Get the x86-64 ELF linker hash table from a link_info structure. */ 497 498#define elf64_x86_64_hash_table(p) \ 499 ((struct elf64_x86_64_link_hash_table *) ((p)->hash)) 500 501#define elf64_x86_64_compute_jump_table_size(htab) \ 502 ((htab)->srelplt->reloc_count * GOT_ENTRY_SIZE) 503 504/* Create an entry in an x86-64 ELF linker hash table. */ 505 506static struct bfd_hash_entry * 507link_hash_newfunc (struct bfd_hash_entry *entry, struct bfd_hash_table *table, 508 const char *string) 509{ 510 /* Allocate the structure if it has not already been allocated by a 511 subclass. */ 512 if (entry == NULL) 513 { 514 entry = bfd_hash_allocate (table, 515 sizeof (struct elf64_x86_64_link_hash_entry)); 516 if (entry == NULL) 517 return entry; 518 } 519 520 /* Call the allocation method of the superclass. */ 521 entry = _bfd_elf_link_hash_newfunc (entry, table, string); 522 if (entry != NULL) 523 { 524 struct elf64_x86_64_link_hash_entry *eh; 525 526 eh = (struct elf64_x86_64_link_hash_entry *) entry; 527 eh->dyn_relocs = NULL; 528 eh->tls_type = GOT_UNKNOWN; 529 eh->tlsdesc_got = (bfd_vma) -1; 530 } 531 532 return entry; 533} 534 535/* Create an X86-64 ELF linker hash table. */ 536 537static struct bfd_link_hash_table * 538elf64_x86_64_link_hash_table_create (bfd *abfd) 539{ 540 struct elf64_x86_64_link_hash_table *ret; 541 bfd_size_type amt = sizeof (struct elf64_x86_64_link_hash_table); 542 543 ret = (struct elf64_x86_64_link_hash_table *) bfd_malloc (amt); 544 if (ret == NULL) 545 return NULL; 546 547 if (!_bfd_elf_link_hash_table_init (&ret->elf, abfd, link_hash_newfunc, 548 sizeof (struct elf64_x86_64_link_hash_entry))) 549 { 550 free (ret); 551 return NULL; 552 } 553 554 ret->sgot = NULL; 555 ret->sgotplt = NULL; 556 ret->srelgot = NULL; 557 ret->splt = NULL; 558 ret->srelplt = NULL; 559 ret->sdynbss = NULL; 560 ret->srelbss = NULL; 561 ret->sym_sec.abfd = NULL; 562 ret->tlsdesc_plt = 0; 563 ret->tlsdesc_got = 0; 564 ret->tls_ld_got.refcount = 0; 565 ret->sgotplt_jump_table_size = 0; 566 567 return &ret->elf.root; 568} 569 570/* Create .got, .gotplt, and .rela.got sections in DYNOBJ, and set up 571 shortcuts to them in our hash table. */ 572 573static bfd_boolean 574create_got_section (bfd *dynobj, struct bfd_link_info *info) 575{ 576 struct elf64_x86_64_link_hash_table *htab; 577 578 if (! _bfd_elf_create_got_section (dynobj, info)) 579 return FALSE; 580 581 htab = elf64_x86_64_hash_table (info); 582 htab->sgot = bfd_get_section_by_name (dynobj, ".got"); 583 htab->sgotplt = bfd_get_section_by_name (dynobj, ".got.plt"); 584 if (!htab->sgot || !htab->sgotplt) 585 abort (); 586 587 htab->srelgot = bfd_make_section_with_flags (dynobj, ".rela.got", 588 (SEC_ALLOC | SEC_LOAD 589 | SEC_HAS_CONTENTS 590 | SEC_IN_MEMORY 591 | SEC_LINKER_CREATED 592 | SEC_READONLY)); 593 if (htab->srelgot == NULL 594 || ! bfd_set_section_alignment (dynobj, htab->srelgot, 3)) 595 return FALSE; 596 return TRUE; 597} 598 599/* Create .plt, .rela.plt, .got, .got.plt, .rela.got, .dynbss, and 600 .rela.bss sections in DYNOBJ, and set up shortcuts to them in our 601 hash table. */ 602 603static bfd_boolean 604elf64_x86_64_create_dynamic_sections (bfd *dynobj, struct bfd_link_info *info) 605{ 606 struct elf64_x86_64_link_hash_table *htab; 607 608 htab = elf64_x86_64_hash_table (info); 609 if (!htab->sgot && !create_got_section (dynobj, info)) 610 return FALSE; 611 612 if (!_bfd_elf_create_dynamic_sections (dynobj, info)) 613 return FALSE; 614 615 htab->splt = bfd_get_section_by_name (dynobj, ".plt"); 616 htab->srelplt = bfd_get_section_by_name (dynobj, ".rela.plt"); 617 htab->sdynbss = bfd_get_section_by_name (dynobj, ".dynbss"); 618 if (!info->shared) 619 htab->srelbss = bfd_get_section_by_name (dynobj, ".rela.bss"); 620 621 if (!htab->splt || !htab->srelplt || !htab->sdynbss 622 || (!info->shared && !htab->srelbss)) 623 abort (); 624 625 return TRUE; 626} 627 628/* Copy the extra info we tack onto an elf_link_hash_entry. */ 629 630static void 631elf64_x86_64_copy_indirect_symbol (struct bfd_link_info *info, 632 struct elf_link_hash_entry *dir, 633 struct elf_link_hash_entry *ind) 634{ 635 struct elf64_x86_64_link_hash_entry *edir, *eind; 636 637 edir = (struct elf64_x86_64_link_hash_entry *) dir; 638 eind = (struct elf64_x86_64_link_hash_entry *) ind; 639 640 if (eind->dyn_relocs != NULL) 641 { 642 if (edir->dyn_relocs != NULL) 643 { 644 struct elf64_x86_64_dyn_relocs **pp; 645 struct elf64_x86_64_dyn_relocs *p; 646 647 /* Add reloc counts against the indirect sym to the direct sym 648 list. Merge any entries against the same section. */ 649 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; ) 650 { 651 struct elf64_x86_64_dyn_relocs *q; 652 653 for (q = edir->dyn_relocs; q != NULL; q = q->next) 654 if (q->sec == p->sec) 655 { 656 q->pc_count += p->pc_count; 657 q->count += p->count; 658 *pp = p->next; 659 break; 660 } 661 if (q == NULL) 662 pp = &p->next; 663 } 664 *pp = edir->dyn_relocs; 665 } 666 667 edir->dyn_relocs = eind->dyn_relocs; 668 eind->dyn_relocs = NULL; 669 } 670 671 if (ind->root.type == bfd_link_hash_indirect 672 && dir->got.refcount <= 0) 673 { 674 edir->tls_type = eind->tls_type; 675 eind->tls_type = GOT_UNKNOWN; 676 } 677 678 if (ELIMINATE_COPY_RELOCS 679 && ind->root.type != bfd_link_hash_indirect 680 && dir->dynamic_adjusted) 681 { 682 /* If called to transfer flags for a weakdef during processing 683 of elf_adjust_dynamic_symbol, don't copy non_got_ref. 684 We clear it ourselves for ELIMINATE_COPY_RELOCS. */ 685 dir->ref_dynamic |= ind->ref_dynamic; 686 dir->ref_regular |= ind->ref_regular; 687 dir->ref_regular_nonweak |= ind->ref_regular_nonweak; 688 dir->needs_plt |= ind->needs_plt; 689 dir->pointer_equality_needed |= ind->pointer_equality_needed; 690 } 691 else 692 _bfd_elf_link_hash_copy_indirect (info, dir, ind); 693} 694 695static bfd_boolean 696elf64_x86_64_mkobject (bfd *abfd) 697{ 698 if (abfd->tdata.any == NULL) 699 { 700 bfd_size_type amt = sizeof (struct elf64_x86_64_obj_tdata); 701 abfd->tdata.any = bfd_zalloc (abfd, amt); 702 if (abfd->tdata.any == NULL) 703 return FALSE; 704 } 705 return bfd_elf_mkobject (abfd); 706} 707 708static bfd_boolean 709elf64_x86_64_elf_object_p (bfd *abfd) 710{ 711 /* Set the right machine number for an x86-64 elf64 file. */ 712 bfd_default_set_arch_mach (abfd, bfd_arch_i386, bfd_mach_x86_64); 713 return TRUE; 714} 715 716typedef union 717 { 718 unsigned char c[2]; 719 uint16_t i; 720 } 721x86_64_opcode16; 722 723typedef union 724 { 725 unsigned char c[4]; 726 uint32_t i; 727 } 728x86_64_opcode32; 729 730/* Return TRUE if the TLS access code sequence support transition 731 from R_TYPE. */ 732 733static bfd_boolean 734elf64_x86_64_check_tls_transition (bfd *abfd, asection *sec, 735 bfd_byte *contents, 736 Elf_Internal_Shdr *symtab_hdr, 737 struct elf_link_hash_entry **sym_hashes, 738 unsigned int r_type, 739 const Elf_Internal_Rela *rel, 740 const Elf_Internal_Rela *relend) 741{ 742 unsigned int val; 743 unsigned long r_symndx; 744 struct elf_link_hash_entry *h; 745 bfd_vma offset; 746 747 /* Get the section contents. */ 748 if (contents == NULL) 749 { 750 if (elf_section_data (sec)->this_hdr.contents != NULL) 751 contents = elf_section_data (sec)->this_hdr.contents; 752 else 753 { 754 /* FIXME: How to better handle error condition? */ 755 if (!bfd_malloc_and_get_section (abfd, sec, &contents)) 756 return FALSE; 757 758 /* Cache the section contents for elf_link_input_bfd. */ 759 elf_section_data (sec)->this_hdr.contents = contents; 760 } 761 } 762 763 offset = rel->r_offset; 764 switch (r_type) 765 { 766 case R_X86_64_TLSGD: 767 case R_X86_64_TLSLD: 768 if ((rel + 1) >= relend) 769 return FALSE; 770 771 if (r_type == R_X86_64_TLSGD) 772 { 773 /* Check transition from GD access model. Only 774 .byte 0x66; leaq foo@tlsgd(%rip), %rdi 775 .word 0x6666; rex64; call __tls_get_addr 776 can transit to different access model. */ 777 778 static x86_64_opcode32 leaq = { { 0x66, 0x48, 0x8d, 0x3d } }, 779 call = { { 0x66, 0x66, 0x48, 0xe8 } }; 780 if (offset < 4 781 || (offset + 12) > sec->size 782 || bfd_get_32 (abfd, contents + offset - 4) != leaq.i 783 || bfd_get_32 (abfd, contents + offset + 4) != call.i) 784 return FALSE; 785 } 786 else 787 { 788 /* Check transition from LD access model. Only 789 leaq foo@tlsld(%rip), %rdi; 790 call __tls_get_addr 791 can transit to different access model. */ 792 793 static x86_64_opcode32 ld = { { 0x48, 0x8d, 0x3d, 0xe8 } }; 794 x86_64_opcode32 op; 795 796 if (offset < 3 || (offset + 9) > sec->size) 797 return FALSE; 798 799 op.i = bfd_get_32 (abfd, contents + offset - 3); 800 op.c[3] = bfd_get_8 (abfd, contents + offset + 4); 801 if (op.i != ld.i) 802 return FALSE; 803 } 804 805 r_symndx = ELF64_R_SYM (rel[1].r_info); 806 if (r_symndx < symtab_hdr->sh_info) 807 return FALSE; 808 809 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 810 return (h != NULL 811 && h->root.root.string != NULL 812 && (ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PC32 813 || ELF64_R_TYPE (rel[1].r_info) == R_X86_64_PLT32) 814 && (strcmp (h->root.root.string, "__tls_get_addr") == 0)); 815 816 case R_X86_64_GOTTPOFF: 817 /* Check transition from IE access model: 818 movq foo@gottpoff(%rip), %reg 819 addq foo@gottpoff(%rip), %reg 820 */ 821 822 if (offset < 3 || (offset + 4) > sec->size) 823 return FALSE; 824 825 val = bfd_get_8 (abfd, contents + offset - 3); 826 if (val != 0x48 && val != 0x4c) 827 return FALSE; 828 829 val = bfd_get_8 (abfd, contents + offset - 2); 830 if (val != 0x8b && val != 0x03) 831 return FALSE; 832 833 val = bfd_get_8 (abfd, contents + offset - 1); 834 return (val & 0xc7) == 5; 835 836 case R_X86_64_GOTPC32_TLSDESC: 837 /* Check transition from GDesc access model: 838 leaq x@tlsdesc(%rip), %rax 839 840 Make sure it's a leaq adding rip to a 32-bit offset 841 into any register, although it's probably almost always 842 going to be rax. */ 843 844 if (offset < 3 || (offset + 4) > sec->size) 845 return FALSE; 846 847 val = bfd_get_8 (abfd, contents + offset - 3); 848 if ((val & 0xfb) != 0x48) 849 return FALSE; 850 851 if (bfd_get_8 (abfd, contents + offset - 2) != 0x8d) 852 return FALSE; 853 854 val = bfd_get_8 (abfd, contents + offset - 1); 855 return (val & 0xc7) == 0x05; 856 857 case R_X86_64_TLSDESC_CALL: 858 /* Check transition from GDesc access model: 859 call *x@tlsdesc(%rax) 860 */ 861 if (offset + 2 <= sec->size) 862 { 863 /* Make sure that it's a call *x@tlsdesc(%rax). */ 864 static x86_64_opcode16 call = { { 0xff, 0x10 } }; 865 return bfd_get_16 (abfd, contents + offset) == call.i; 866 } 867 868 return FALSE; 869 870 default: 871 abort (); 872 } 873} 874 875/* Return TRUE if the TLS access transition is OK or no transition 876 will be performed. Update R_TYPE if there is a transition. */ 877 878static bfd_boolean 879elf64_x86_64_tls_transition (struct bfd_link_info *info, bfd *abfd, 880 asection *sec, bfd_byte *contents, 881 Elf_Internal_Shdr *symtab_hdr, 882 struct elf_link_hash_entry **sym_hashes, 883 unsigned int *r_type, int tls_type, 884 const Elf_Internal_Rela *rel, 885 const Elf_Internal_Rela *relend, 886 struct elf_link_hash_entry *h) 887{ 888 unsigned int from_type = *r_type; 889 unsigned int to_type = from_type; 890 bfd_boolean check = TRUE; 891 892 switch (from_type) 893 { 894 case R_X86_64_TLSGD: 895 case R_X86_64_GOTPC32_TLSDESC: 896 case R_X86_64_TLSDESC_CALL: 897 case R_X86_64_GOTTPOFF: 898 if (!info->shared) 899 { 900 if (h == NULL) 901 to_type = R_X86_64_TPOFF32; 902 else 903 to_type = R_X86_64_GOTTPOFF; 904 } 905 906 /* When we are called from elf64_x86_64_relocate_section, 907 CONTENTS isn't NULL and there may be additional transitions 908 based on TLS_TYPE. */ 909 if (contents != NULL) 910 { 911 unsigned int new_to_type = to_type; 912 913 if (!info->shared 914 && h != NULL 915 && h->dynindx == -1 916 && tls_type == GOT_TLS_IE) 917 new_to_type = R_X86_64_TPOFF32; 918 919 if (to_type == R_X86_64_TLSGD 920 || to_type == R_X86_64_GOTPC32_TLSDESC 921 || to_type == R_X86_64_TLSDESC_CALL) 922 { 923 if (tls_type == GOT_TLS_IE) 924 new_to_type = R_X86_64_GOTTPOFF; 925 } 926 927 /* We checked the transition before when we were called from 928 elf64_x86_64_check_relocs. We only want to check the new 929 transition which hasn't been checked before. */ 930 check = new_to_type != to_type && from_type == to_type; 931 to_type = new_to_type; 932 } 933 934 break; 935 936 case R_X86_64_TLSLD: 937 if (!info->shared) 938 to_type = R_X86_64_TPOFF32; 939 break; 940 941 default: 942 return TRUE; 943 } 944 945 /* Return TRUE if there is no transition. */ 946 if (from_type == to_type) 947 return TRUE; 948 949 /* Check if the transition can be performed. */ 950 if (check 951 && ! elf64_x86_64_check_tls_transition (abfd, sec, contents, 952 symtab_hdr, sym_hashes, 953 from_type, rel, relend)) 954 { 955 const reloc_howto_type *from, *to; 956 957 from = elf64_x86_64_rtype_to_howto (abfd, from_type); 958 to = elf64_x86_64_rtype_to_howto (abfd, to_type); 959 960 (*_bfd_error_handler) 961 (_("%B: TLS transition from %s to %s against `%s' at 0x%lx " 962 "in section `%A' failed"), 963 abfd, sec, from->name, to->name, 964 h ? h->root.root.string : "a local symbol", 965 (unsigned long) rel->r_offset); 966 bfd_set_error (bfd_error_bad_value); 967 return FALSE; 968 } 969 970 *r_type = to_type; 971 return TRUE; 972} 973 974/* Look through the relocs for a section during the first phase, and 975 calculate needed space in the global offset table, procedure 976 linkage table, and dynamic reloc sections. */ 977 978static bfd_boolean 979elf64_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info, 980 asection *sec, 981 const Elf_Internal_Rela *relocs) 982{ 983 struct elf64_x86_64_link_hash_table *htab; 984 Elf_Internal_Shdr *symtab_hdr; 985 struct elf_link_hash_entry **sym_hashes; 986 const Elf_Internal_Rela *rel; 987 const Elf_Internal_Rela *rel_end; 988 asection *sreloc; 989 990 if (info->relocatable) 991 return TRUE; 992 993 htab = elf64_x86_64_hash_table (info); 994 symtab_hdr = &elf_tdata (abfd)->symtab_hdr; 995 sym_hashes = elf_sym_hashes (abfd); 996 997 sreloc = NULL; 998 999 rel_end = relocs + sec->reloc_count; 1000 for (rel = relocs; rel < rel_end; rel++) 1001 { 1002 unsigned int r_type; 1003 unsigned long r_symndx; 1004 struct elf_link_hash_entry *h; 1005 1006 r_symndx = ELF64_R_SYM (rel->r_info); 1007 r_type = ELF64_R_TYPE (rel->r_info); 1008 1009 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr)) 1010 { 1011 (*_bfd_error_handler) (_("%B: bad symbol index: %d"), 1012 abfd, r_symndx); 1013 return FALSE; 1014 } 1015 1016 if (r_symndx < symtab_hdr->sh_info) 1017 h = NULL; 1018 else 1019 { 1020 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 1021 while (h->root.type == bfd_link_hash_indirect 1022 || h->root.type == bfd_link_hash_warning) 1023 h = (struct elf_link_hash_entry *) h->root.u.i.link; 1024 } 1025 1026 if (! elf64_x86_64_tls_transition (info, abfd, sec, NULL, 1027 symtab_hdr, sym_hashes, 1028 &r_type, GOT_UNKNOWN, 1029 rel, rel_end, h)) 1030 return FALSE; 1031 1032 switch (r_type) 1033 { 1034 case R_X86_64_TLSLD: 1035 htab->tls_ld_got.refcount += 1; 1036 goto create_got; 1037 1038 case R_X86_64_TPOFF32: 1039 if (info->shared) 1040 { 1041 (*_bfd_error_handler) 1042 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"), 1043 abfd, 1044 x86_64_elf_howto_table[r_type].name, 1045 (h) ? h->root.root.string : "a local symbol"); 1046 bfd_set_error (bfd_error_bad_value); 1047 return FALSE; 1048 } 1049 break; 1050 1051 case R_X86_64_GOTTPOFF: 1052 if (info->shared) 1053 info->flags |= DF_STATIC_TLS; 1054 /* Fall through */ 1055 1056 case R_X86_64_GOT32: 1057 case R_X86_64_GOTPCREL: 1058 case R_X86_64_TLSGD: 1059 case R_X86_64_GOT64: 1060 case R_X86_64_GOTPCREL64: 1061 case R_X86_64_GOTPLT64: 1062 case R_X86_64_GOTPC32_TLSDESC: 1063 case R_X86_64_TLSDESC_CALL: 1064 /* This symbol requires a global offset table entry. */ 1065 { 1066 int tls_type, old_tls_type; 1067 1068 switch (r_type) 1069 { 1070 default: tls_type = GOT_NORMAL; break; 1071 case R_X86_64_TLSGD: tls_type = GOT_TLS_GD; break; 1072 case R_X86_64_GOTTPOFF: tls_type = GOT_TLS_IE; break; 1073 case R_X86_64_GOTPC32_TLSDESC: 1074 case R_X86_64_TLSDESC_CALL: 1075 tls_type = GOT_TLS_GDESC; break; 1076 } 1077 1078 if (h != NULL) 1079 { 1080 if (r_type == R_X86_64_GOTPLT64) 1081 { 1082 /* This relocation indicates that we also need 1083 a PLT entry, as this is a function. We don't need 1084 a PLT entry for local symbols. */ 1085 h->needs_plt = 1; 1086 h->plt.refcount += 1; 1087 } 1088 h->got.refcount += 1; 1089 old_tls_type = elf64_x86_64_hash_entry (h)->tls_type; 1090 } 1091 else 1092 { 1093 bfd_signed_vma *local_got_refcounts; 1094 1095 /* This is a global offset table entry for a local symbol. */ 1096 local_got_refcounts = elf_local_got_refcounts (abfd); 1097 if (local_got_refcounts == NULL) 1098 { 1099 bfd_size_type size; 1100 1101 size = symtab_hdr->sh_info; 1102 size *= sizeof (bfd_signed_vma) 1103 + sizeof (bfd_vma) + sizeof (char); 1104 local_got_refcounts = ((bfd_signed_vma *) 1105 bfd_zalloc (abfd, size)); 1106 if (local_got_refcounts == NULL) 1107 return FALSE; 1108 elf_local_got_refcounts (abfd) = local_got_refcounts; 1109 elf64_x86_64_local_tlsdesc_gotent (abfd) 1110 = (bfd_vma *) (local_got_refcounts + symtab_hdr->sh_info); 1111 elf64_x86_64_local_got_tls_type (abfd) 1112 = (char *) (local_got_refcounts + 2 * symtab_hdr->sh_info); 1113 } 1114 local_got_refcounts[r_symndx] += 1; 1115 old_tls_type 1116 = elf64_x86_64_local_got_tls_type (abfd) [r_symndx]; 1117 } 1118 1119 /* If a TLS symbol is accessed using IE at least once, 1120 there is no point to use dynamic model for it. */ 1121 if (old_tls_type != tls_type && old_tls_type != GOT_UNKNOWN 1122 && (! GOT_TLS_GD_ANY_P (old_tls_type) 1123 || tls_type != GOT_TLS_IE)) 1124 { 1125 if (old_tls_type == GOT_TLS_IE && GOT_TLS_GD_ANY_P (tls_type)) 1126 tls_type = old_tls_type; 1127 else if (GOT_TLS_GD_ANY_P (old_tls_type) 1128 && GOT_TLS_GD_ANY_P (tls_type)) 1129 tls_type |= old_tls_type; 1130 else 1131 { 1132 (*_bfd_error_handler) 1133 (_("%B: %s' accessed both as normal and thread local symbol"), 1134 abfd, h ? h->root.root.string : "<local>"); 1135 return FALSE; 1136 } 1137 } 1138 1139 if (old_tls_type != tls_type) 1140 { 1141 if (h != NULL) 1142 elf64_x86_64_hash_entry (h)->tls_type = tls_type; 1143 else 1144 elf64_x86_64_local_got_tls_type (abfd) [r_symndx] = tls_type; 1145 } 1146 } 1147 /* Fall through */ 1148 1149 case R_X86_64_GOTOFF64: 1150 case R_X86_64_GOTPC32: 1151 case R_X86_64_GOTPC64: 1152 create_got: 1153 if (htab->sgot == NULL) 1154 { 1155 if (htab->elf.dynobj == NULL) 1156 htab->elf.dynobj = abfd; 1157 if (!create_got_section (htab->elf.dynobj, info)) 1158 return FALSE; 1159 } 1160 break; 1161 1162 case R_X86_64_PLT32: 1163 /* This symbol requires a procedure linkage table entry. We 1164 actually build the entry in adjust_dynamic_symbol, 1165 because this might be a case of linking PIC code which is 1166 never referenced by a dynamic object, in which case we 1167 don't need to generate a procedure linkage table entry 1168 after all. */ 1169 1170 /* If this is a local symbol, we resolve it directly without 1171 creating a procedure linkage table entry. */ 1172 if (h == NULL) 1173 continue; 1174 1175 h->needs_plt = 1; 1176 h->plt.refcount += 1; 1177 break; 1178 1179 case R_X86_64_PLTOFF64: 1180 /* This tries to form the 'address' of a function relative 1181 to GOT. For global symbols we need a PLT entry. */ 1182 if (h != NULL) 1183 { 1184 h->needs_plt = 1; 1185 h->plt.refcount += 1; 1186 } 1187 goto create_got; 1188 1189 case R_X86_64_8: 1190 case R_X86_64_16: 1191 case R_X86_64_32: 1192 case R_X86_64_32S: 1193 /* Let's help debug shared library creation. These relocs 1194 cannot be used in shared libs. Don't error out for 1195 sections we don't care about, such as debug sections or 1196 non-constant sections. */ 1197 if (info->shared 1198 && (sec->flags & SEC_ALLOC) != 0 1199 && (sec->flags & SEC_READONLY) != 0) 1200 { 1201 (*_bfd_error_handler) 1202 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"), 1203 abfd, 1204 x86_64_elf_howto_table[r_type].name, 1205 (h) ? h->root.root.string : "a local symbol"); 1206 bfd_set_error (bfd_error_bad_value); 1207 return FALSE; 1208 } 1209 /* Fall through. */ 1210 1211 case R_X86_64_PC8: 1212 case R_X86_64_PC16: 1213 case R_X86_64_PC32: 1214 case R_X86_64_PC64: 1215 case R_X86_64_64: 1216 if (h != NULL && !info->shared) 1217 { 1218 /* If this reloc is in a read-only section, we might 1219 need a copy reloc. We can't check reliably at this 1220 stage whether the section is read-only, as input 1221 sections have not yet been mapped to output sections. 1222 Tentatively set the flag for now, and correct in 1223 adjust_dynamic_symbol. */ 1224 h->non_got_ref = 1; 1225 1226 /* We may need a .plt entry if the function this reloc 1227 refers to is in a shared lib. */ 1228 h->plt.refcount += 1; 1229 if (r_type != R_X86_64_PC32 && r_type != R_X86_64_PC64) 1230 h->pointer_equality_needed = 1; 1231 } 1232 1233 /* If we are creating a shared library, and this is a reloc 1234 against a global symbol, or a non PC relative reloc 1235 against a local symbol, then we need to copy the reloc 1236 into the shared library. However, if we are linking with 1237 -Bsymbolic, we do not need to copy a reloc against a 1238 global symbol which is defined in an object we are 1239 including in the link (i.e., DEF_REGULAR is set). At 1240 this point we have not seen all the input files, so it is 1241 possible that DEF_REGULAR is not set now but will be set 1242 later (it is never cleared). In case of a weak definition, 1243 DEF_REGULAR may be cleared later by a strong definition in 1244 a shared library. We account for that possibility below by 1245 storing information in the relocs_copied field of the hash 1246 table entry. A similar situation occurs when creating 1247 shared libraries and symbol visibility changes render the 1248 symbol local. 1249 1250 If on the other hand, we are creating an executable, we 1251 may need to keep relocations for symbols satisfied by a 1252 dynamic library if we manage to avoid copy relocs for the 1253 symbol. */ 1254 if ((info->shared 1255 && (sec->flags & SEC_ALLOC) != 0 1256 && (((r_type != R_X86_64_PC8) 1257 && (r_type != R_X86_64_PC16) 1258 && (r_type != R_X86_64_PC32) 1259 && (r_type != R_X86_64_PC64)) 1260 || (h != NULL 1261 && (! SYMBOLIC_BIND (info, h) 1262 || h->root.type == bfd_link_hash_defweak 1263 || !h->def_regular)))) 1264 || (ELIMINATE_COPY_RELOCS 1265 && !info->shared 1266 && (sec->flags & SEC_ALLOC) != 0 1267 && h != NULL 1268 && (h->root.type == bfd_link_hash_defweak 1269 || !h->def_regular))) 1270 { 1271 struct elf64_x86_64_dyn_relocs *p; 1272 struct elf64_x86_64_dyn_relocs **head; 1273 1274 /* We must copy these reloc types into the output file. 1275 Create a reloc section in dynobj and make room for 1276 this reloc. */ 1277 if (sreloc == NULL) 1278 { 1279 const char *name; 1280 bfd *dynobj; 1281 1282 name = (bfd_elf_string_from_elf_section 1283 (abfd, 1284 elf_elfheader (abfd)->e_shstrndx, 1285 elf_section_data (sec)->rel_hdr.sh_name)); 1286 if (name == NULL) 1287 return FALSE; 1288 1289 if (! CONST_STRNEQ (name, ".rela") 1290 || strcmp (bfd_get_section_name (abfd, sec), 1291 name + 5) != 0) 1292 { 1293 (*_bfd_error_handler) 1294 (_("%B: bad relocation section name `%s\'"), 1295 abfd, name); 1296 } 1297 1298 if (htab->elf.dynobj == NULL) 1299 htab->elf.dynobj = abfd; 1300 1301 dynobj = htab->elf.dynobj; 1302 1303 sreloc = bfd_get_section_by_name (dynobj, name); 1304 if (sreloc == NULL) 1305 { 1306 flagword flags; 1307 1308 flags = (SEC_HAS_CONTENTS | SEC_READONLY 1309 | SEC_IN_MEMORY | SEC_LINKER_CREATED); 1310 if ((sec->flags & SEC_ALLOC) != 0) 1311 flags |= SEC_ALLOC | SEC_LOAD; 1312 sreloc = bfd_make_section_with_flags (dynobj, 1313 name, 1314 flags); 1315 if (sreloc == NULL 1316 || ! bfd_set_section_alignment (dynobj, sreloc, 3)) 1317 return FALSE; 1318 } 1319 elf_section_data (sec)->sreloc = sreloc; 1320 } 1321 1322 /* If this is a global symbol, we count the number of 1323 relocations we need for this symbol. */ 1324 if (h != NULL) 1325 { 1326 head = &((struct elf64_x86_64_link_hash_entry *) h)->dyn_relocs; 1327 } 1328 else 1329 { 1330 void **vpp; 1331 /* Track dynamic relocs needed for local syms too. 1332 We really need local syms available to do this 1333 easily. Oh well. */ 1334 1335 asection *s; 1336 s = bfd_section_from_r_symndx (abfd, &htab->sym_sec, 1337 sec, r_symndx); 1338 if (s == NULL) 1339 return FALSE; 1340 1341 /* Beware of type punned pointers vs strict aliasing 1342 rules. */ 1343 vpp = &(elf_section_data (s)->local_dynrel); 1344 head = (struct elf64_x86_64_dyn_relocs **)vpp; 1345 } 1346 1347 p = *head; 1348 if (p == NULL || p->sec != sec) 1349 { 1350 bfd_size_type amt = sizeof *p; 1351 p = ((struct elf64_x86_64_dyn_relocs *) 1352 bfd_alloc (htab->elf.dynobj, amt)); 1353 if (p == NULL) 1354 return FALSE; 1355 p->next = *head; 1356 *head = p; 1357 p->sec = sec; 1358 p->count = 0; 1359 p->pc_count = 0; 1360 } 1361 1362 p->count += 1; 1363 if (r_type == R_X86_64_PC8 1364 || r_type == R_X86_64_PC16 1365 || r_type == R_X86_64_PC32 1366 || r_type == R_X86_64_PC64) 1367 p->pc_count += 1; 1368 } 1369 break; 1370 1371 /* This relocation describes the C++ object vtable hierarchy. 1372 Reconstruct it for later use during GC. */ 1373 case R_X86_64_GNU_VTINHERIT: 1374 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset)) 1375 return FALSE; 1376 break; 1377 1378 /* This relocation describes which C++ vtable entries are actually 1379 used. Record for later use during GC. */ 1380 case R_X86_64_GNU_VTENTRY: 1381 if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend)) 1382 return FALSE; 1383 break; 1384 1385 default: 1386 break; 1387 } 1388 } 1389 1390 return TRUE; 1391} 1392 1393/* Return the section that should be marked against GC for a given 1394 relocation. */ 1395 1396static asection * 1397elf64_x86_64_gc_mark_hook (asection *sec, 1398 struct bfd_link_info *info, 1399 Elf_Internal_Rela *rel, 1400 struct elf_link_hash_entry *h, 1401 Elf_Internal_Sym *sym) 1402{ 1403 if (h != NULL) 1404 switch (ELF64_R_TYPE (rel->r_info)) 1405 { 1406 case R_X86_64_GNU_VTINHERIT: 1407 case R_X86_64_GNU_VTENTRY: 1408 return NULL; 1409 } 1410 1411 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym); 1412} 1413 1414/* Update the got entry reference counts for the section being removed. */ 1415 1416static bfd_boolean 1417elf64_x86_64_gc_sweep_hook (bfd *abfd, struct bfd_link_info *info, 1418 asection *sec, 1419 const Elf_Internal_Rela *relocs) 1420{ 1421 Elf_Internal_Shdr *symtab_hdr; 1422 struct elf_link_hash_entry **sym_hashes; 1423 bfd_signed_vma *local_got_refcounts; 1424 const Elf_Internal_Rela *rel, *relend; 1425 1426 elf_section_data (sec)->local_dynrel = NULL; 1427 1428 symtab_hdr = &elf_tdata (abfd)->symtab_hdr; 1429 sym_hashes = elf_sym_hashes (abfd); 1430 local_got_refcounts = elf_local_got_refcounts (abfd); 1431 1432 relend = relocs + sec->reloc_count; 1433 for (rel = relocs; rel < relend; rel++) 1434 { 1435 unsigned long r_symndx; 1436 unsigned int r_type; 1437 struct elf_link_hash_entry *h = NULL; 1438 1439 r_symndx = ELF64_R_SYM (rel->r_info); 1440 if (r_symndx >= symtab_hdr->sh_info) 1441 { 1442 struct elf64_x86_64_link_hash_entry *eh; 1443 struct elf64_x86_64_dyn_relocs **pp; 1444 struct elf64_x86_64_dyn_relocs *p; 1445 1446 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 1447 while (h->root.type == bfd_link_hash_indirect 1448 || h->root.type == bfd_link_hash_warning) 1449 h = (struct elf_link_hash_entry *) h->root.u.i.link; 1450 eh = (struct elf64_x86_64_link_hash_entry *) h; 1451 1452 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next) 1453 if (p->sec == sec) 1454 { 1455 /* Everything must go for SEC. */ 1456 *pp = p->next; 1457 break; 1458 } 1459 } 1460 1461 r_type = ELF64_R_TYPE (rel->r_info); 1462 if (! elf64_x86_64_tls_transition (info, abfd, sec, NULL, 1463 symtab_hdr, sym_hashes, 1464 &r_type, GOT_UNKNOWN, 1465 rel, relend, h)) 1466 return FALSE; 1467 1468 switch (r_type) 1469 { 1470 case R_X86_64_TLSLD: 1471 if (elf64_x86_64_hash_table (info)->tls_ld_got.refcount > 0) 1472 elf64_x86_64_hash_table (info)->tls_ld_got.refcount -= 1; 1473 break; 1474 1475 case R_X86_64_TLSGD: 1476 case R_X86_64_GOTPC32_TLSDESC: 1477 case R_X86_64_TLSDESC_CALL: 1478 case R_X86_64_GOTTPOFF: 1479 case R_X86_64_GOT32: 1480 case R_X86_64_GOTPCREL: 1481 case R_X86_64_GOT64: 1482 case R_X86_64_GOTPCREL64: 1483 case R_X86_64_GOTPLT64: 1484 if (h != NULL) 1485 { 1486 if (r_type == R_X86_64_GOTPLT64 && h->plt.refcount > 0) 1487 h->plt.refcount -= 1; 1488 if (h->got.refcount > 0) 1489 h->got.refcount -= 1; 1490 } 1491 else if (local_got_refcounts != NULL) 1492 { 1493 if (local_got_refcounts[r_symndx] > 0) 1494 local_got_refcounts[r_symndx] -= 1; 1495 } 1496 break; 1497 1498 case R_X86_64_8: 1499 case R_X86_64_16: 1500 case R_X86_64_32: 1501 case R_X86_64_64: 1502 case R_X86_64_32S: 1503 case R_X86_64_PC8: 1504 case R_X86_64_PC16: 1505 case R_X86_64_PC32: 1506 case R_X86_64_PC64: 1507 if (info->shared) 1508 break; 1509 /* Fall thru */ 1510 1511 case R_X86_64_PLT32: 1512 case R_X86_64_PLTOFF64: 1513 if (h != NULL) 1514 { 1515 if (h->plt.refcount > 0) 1516 h->plt.refcount -= 1; 1517 } 1518 break; 1519 1520 default: 1521 break; 1522 } 1523 } 1524 1525 return TRUE; 1526} 1527 1528/* Adjust a symbol defined by a dynamic object and referenced by a 1529 regular object. The current definition is in some section of the 1530 dynamic object, but we're not including those sections. We have to 1531 change the definition to something the rest of the link can 1532 understand. */ 1533 1534static bfd_boolean 1535elf64_x86_64_adjust_dynamic_symbol (struct bfd_link_info *info, 1536 struct elf_link_hash_entry *h) 1537{ 1538 struct elf64_x86_64_link_hash_table *htab; 1539 asection *s; 1540 1541 /* If this is a function, put it in the procedure linkage table. We 1542 will fill in the contents of the procedure linkage table later, 1543 when we know the address of the .got section. */ 1544 if (h->type == STT_FUNC 1545 || h->needs_plt) 1546 { 1547 if (h->plt.refcount <= 0 1548 || SYMBOL_CALLS_LOCAL (info, h) 1549 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT 1550 && h->root.type == bfd_link_hash_undefweak)) 1551 { 1552 /* This case can occur if we saw a PLT32 reloc in an input 1553 file, but the symbol was never referred to by a dynamic 1554 object, or if all references were garbage collected. In 1555 such a case, we don't actually need to build a procedure 1556 linkage table, and we can just do a PC32 reloc instead. */ 1557 h->plt.offset = (bfd_vma) -1; 1558 h->needs_plt = 0; 1559 } 1560 1561 return TRUE; 1562 } 1563 else 1564 /* It's possible that we incorrectly decided a .plt reloc was 1565 needed for an R_X86_64_PC32 reloc to a non-function sym in 1566 check_relocs. We can't decide accurately between function and 1567 non-function syms in check-relocs; Objects loaded later in 1568 the link may change h->type. So fix it now. */ 1569 h->plt.offset = (bfd_vma) -1; 1570 1571 /* If this is a weak symbol, and there is a real definition, the 1572 processor independent code will have arranged for us to see the 1573 real definition first, and we can just use the same value. */ 1574 if (h->u.weakdef != NULL) 1575 { 1576 BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined 1577 || h->u.weakdef->root.type == bfd_link_hash_defweak); 1578 h->root.u.def.section = h->u.weakdef->root.u.def.section; 1579 h->root.u.def.value = h->u.weakdef->root.u.def.value; 1580 if (ELIMINATE_COPY_RELOCS || info->nocopyreloc) 1581 h->non_got_ref = h->u.weakdef->non_got_ref; 1582 return TRUE; 1583 } 1584 1585 /* This is a reference to a symbol defined by a dynamic object which 1586 is not a function. */ 1587 1588 /* If we are creating a shared library, we must presume that the 1589 only references to the symbol are via the global offset table. 1590 For such cases we need not do anything here; the relocations will 1591 be handled correctly by relocate_section. */ 1592 if (info->shared) 1593 return TRUE; 1594 1595 /* If there are no references to this symbol that do not use the 1596 GOT, we don't need to generate a copy reloc. */ 1597 if (!h->non_got_ref) 1598 return TRUE; 1599 1600 /* If -z nocopyreloc was given, we won't generate them either. */ 1601 if (info->nocopyreloc) 1602 { 1603 h->non_got_ref = 0; 1604 return TRUE; 1605 } 1606 1607 if (ELIMINATE_COPY_RELOCS) 1608 { 1609 struct elf64_x86_64_link_hash_entry * eh; 1610 struct elf64_x86_64_dyn_relocs *p; 1611 1612 eh = (struct elf64_x86_64_link_hash_entry *) h; 1613 for (p = eh->dyn_relocs; p != NULL; p = p->next) 1614 { 1615 s = p->sec->output_section; 1616 if (s != NULL && (s->flags & SEC_READONLY) != 0) 1617 break; 1618 } 1619 1620 /* If we didn't find any dynamic relocs in read-only sections, then 1621 we'll be keeping the dynamic relocs and avoiding the copy reloc. */ 1622 if (p == NULL) 1623 { 1624 h->non_got_ref = 0; 1625 return TRUE; 1626 } 1627 } 1628 1629 if (h->size == 0) 1630 { 1631 (*_bfd_error_handler) (_("dynamic variable `%s' is zero size"), 1632 h->root.root.string); 1633 return TRUE; 1634 } 1635 1636 /* We must allocate the symbol in our .dynbss section, which will 1637 become part of the .bss section of the executable. There will be 1638 an entry for this symbol in the .dynsym section. The dynamic 1639 object will contain position independent code, so all references 1640 from the dynamic object to this symbol will go through the global 1641 offset table. The dynamic linker will use the .dynsym entry to 1642 determine the address it must put in the global offset table, so 1643 both the dynamic object and the regular object will refer to the 1644 same memory location for the variable. */ 1645 1646 htab = elf64_x86_64_hash_table (info); 1647 1648 /* We must generate a R_X86_64_COPY reloc to tell the dynamic linker 1649 to copy the initial value out of the dynamic object and into the 1650 runtime process image. */ 1651 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0) 1652 { 1653 htab->srelbss->size += sizeof (Elf64_External_Rela); 1654 h->needs_copy = 1; 1655 } 1656 1657 s = htab->sdynbss; 1658 1659 return _bfd_elf_adjust_dynamic_copy (h, s); 1660} 1661 1662/* Allocate space in .plt, .got and associated reloc sections for 1663 dynamic relocs. */ 1664 1665static bfd_boolean 1666allocate_dynrelocs (struct elf_link_hash_entry *h, void * inf) 1667{ 1668 struct bfd_link_info *info; 1669 struct elf64_x86_64_link_hash_table *htab; 1670 struct elf64_x86_64_link_hash_entry *eh; 1671 struct elf64_x86_64_dyn_relocs *p; 1672 1673 if (h->root.type == bfd_link_hash_indirect) 1674 return TRUE; 1675 1676 if (h->root.type == bfd_link_hash_warning) 1677 h = (struct elf_link_hash_entry *) h->root.u.i.link; 1678 1679 info = (struct bfd_link_info *) inf; 1680 htab = elf64_x86_64_hash_table (info); 1681 1682 if (htab->elf.dynamic_sections_created 1683 && h->plt.refcount > 0) 1684 { 1685 /* Make sure this symbol is output as a dynamic symbol. 1686 Undefined weak syms won't yet be marked as dynamic. */ 1687 if (h->dynindx == -1 1688 && !h->forced_local) 1689 { 1690 if (! bfd_elf_link_record_dynamic_symbol (info, h)) 1691 return FALSE; 1692 } 1693 1694 if (info->shared 1695 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h)) 1696 { 1697 asection *s = htab->splt; 1698 1699 /* If this is the first .plt entry, make room for the special 1700 first entry. */ 1701 if (s->size == 0) 1702 s->size += PLT_ENTRY_SIZE; 1703 1704 h->plt.offset = s->size; 1705 1706 /* If this symbol is not defined in a regular file, and we are 1707 not generating a shared library, then set the symbol to this 1708 location in the .plt. This is required to make function 1709 pointers compare as equal between the normal executable and 1710 the shared library. */ 1711 if (! info->shared 1712 && !h->def_regular) 1713 { 1714 h->root.u.def.section = s; 1715 h->root.u.def.value = h->plt.offset; 1716 } 1717 1718 /* Make room for this entry. */ 1719 s->size += PLT_ENTRY_SIZE; 1720 1721 /* We also need to make an entry in the .got.plt section, which 1722 will be placed in the .got section by the linker script. */ 1723 htab->sgotplt->size += GOT_ENTRY_SIZE; 1724 1725 /* We also need to make an entry in the .rela.plt section. */ 1726 htab->srelplt->size += sizeof (Elf64_External_Rela); 1727 htab->srelplt->reloc_count++; 1728 } 1729 else 1730 { 1731 h->plt.offset = (bfd_vma) -1; 1732 h->needs_plt = 0; 1733 } 1734 } 1735 else 1736 { 1737 h->plt.offset = (bfd_vma) -1; 1738 h->needs_plt = 0; 1739 } 1740 1741 eh = (struct elf64_x86_64_link_hash_entry *) h; 1742 eh->tlsdesc_got = (bfd_vma) -1; 1743 1744 /* If R_X86_64_GOTTPOFF symbol is now local to the binary, 1745 make it a R_X86_64_TPOFF32 requiring no GOT entry. */ 1746 if (h->got.refcount > 0 1747 && !info->shared 1748 && h->dynindx == -1 1749 && elf64_x86_64_hash_entry (h)->tls_type == GOT_TLS_IE) 1750 h->got.offset = (bfd_vma) -1; 1751 else if (h->got.refcount > 0) 1752 { 1753 asection *s; 1754 bfd_boolean dyn; 1755 int tls_type = elf64_x86_64_hash_entry (h)->tls_type; 1756 1757 /* Make sure this symbol is output as a dynamic symbol. 1758 Undefined weak syms won't yet be marked as dynamic. */ 1759 if (h->dynindx == -1 1760 && !h->forced_local) 1761 { 1762 if (! bfd_elf_link_record_dynamic_symbol (info, h)) 1763 return FALSE; 1764 } 1765 1766 if (GOT_TLS_GDESC_P (tls_type)) 1767 { 1768 eh->tlsdesc_got = htab->sgotplt->size 1769 - elf64_x86_64_compute_jump_table_size (htab); 1770 htab->sgotplt->size += 2 * GOT_ENTRY_SIZE; 1771 h->got.offset = (bfd_vma) -2; 1772 } 1773 if (! GOT_TLS_GDESC_P (tls_type) 1774 || GOT_TLS_GD_P (tls_type)) 1775 { 1776 s = htab->sgot; 1777 h->got.offset = s->size; 1778 s->size += GOT_ENTRY_SIZE; 1779 if (GOT_TLS_GD_P (tls_type)) 1780 s->size += GOT_ENTRY_SIZE; 1781 } 1782 dyn = htab->elf.dynamic_sections_created; 1783 /* R_X86_64_TLSGD needs one dynamic relocation if local symbol 1784 and two if global. 1785 R_X86_64_GOTTPOFF needs one dynamic relocation. */ 1786 if ((GOT_TLS_GD_P (tls_type) && h->dynindx == -1) 1787 || tls_type == GOT_TLS_IE) 1788 htab->srelgot->size += sizeof (Elf64_External_Rela); 1789 else if (GOT_TLS_GD_P (tls_type)) 1790 htab->srelgot->size += 2 * sizeof (Elf64_External_Rela); 1791 else if (! GOT_TLS_GDESC_P (tls_type) 1792 && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT 1793 || h->root.type != bfd_link_hash_undefweak) 1794 && (info->shared 1795 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h))) 1796 htab->srelgot->size += sizeof (Elf64_External_Rela); 1797 if (GOT_TLS_GDESC_P (tls_type)) 1798 { 1799 htab->srelplt->size += sizeof (Elf64_External_Rela); 1800 htab->tlsdesc_plt = (bfd_vma) -1; 1801 } 1802 } 1803 else 1804 h->got.offset = (bfd_vma) -1; 1805 1806 if (eh->dyn_relocs == NULL) 1807 return TRUE; 1808 1809 /* In the shared -Bsymbolic case, discard space allocated for 1810 dynamic pc-relative relocs against symbols which turn out to be 1811 defined in regular objects. For the normal shared case, discard 1812 space for pc-relative relocs that have become local due to symbol 1813 visibility changes. */ 1814 1815 if (info->shared) 1816 { 1817 /* Relocs that use pc_count are those that appear on a call 1818 insn, or certain REL relocs that can generated via assembly. 1819 We want calls to protected symbols to resolve directly to the 1820 function rather than going via the plt. If people want 1821 function pointer comparisons to work as expected then they 1822 should avoid writing weird assembly. */ 1823 if (SYMBOL_CALLS_LOCAL (info, h)) 1824 { 1825 struct elf64_x86_64_dyn_relocs **pp; 1826 1827 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; ) 1828 { 1829 p->count -= p->pc_count; 1830 p->pc_count = 0; 1831 if (p->count == 0) 1832 *pp = p->next; 1833 else 1834 pp = &p->next; 1835 } 1836 } 1837 1838 /* Also discard relocs on undefined weak syms with non-default 1839 visibility. */ 1840 if (eh->dyn_relocs != NULL 1841 && h->root.type == bfd_link_hash_undefweak) 1842 { 1843 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT) 1844 eh->dyn_relocs = NULL; 1845 1846 /* Make sure undefined weak symbols are output as a dynamic 1847 symbol in PIEs. */ 1848 else if (h->dynindx == -1 1849 && !h->forced_local) 1850 { 1851 if (! bfd_elf_link_record_dynamic_symbol (info, h)) 1852 return FALSE; 1853 } 1854 } 1855 } 1856 else if (ELIMINATE_COPY_RELOCS) 1857 { 1858 /* For the non-shared case, discard space for relocs against 1859 symbols which turn out to need copy relocs or are not 1860 dynamic. */ 1861 1862 if (!h->non_got_ref 1863 && ((h->def_dynamic 1864 && !h->def_regular) 1865 || (htab->elf.dynamic_sections_created 1866 && (h->root.type == bfd_link_hash_undefweak 1867 || h->root.type == bfd_link_hash_undefined)))) 1868 { 1869 /* Make sure this symbol is output as a dynamic symbol. 1870 Undefined weak syms won't yet be marked as dynamic. */ 1871 if (h->dynindx == -1 1872 && !h->forced_local) 1873 { 1874 if (! bfd_elf_link_record_dynamic_symbol (info, h)) 1875 return FALSE; 1876 } 1877 1878 /* If that succeeded, we know we'll be keeping all the 1879 relocs. */ 1880 if (h->dynindx != -1) 1881 goto keep; 1882 } 1883 1884 eh->dyn_relocs = NULL; 1885 1886 keep: ; 1887 } 1888 1889 /* Finally, allocate space. */ 1890 for (p = eh->dyn_relocs; p != NULL; p = p->next) 1891 { 1892 asection *sreloc = elf_section_data (p->sec)->sreloc; 1893 sreloc->size += p->count * sizeof (Elf64_External_Rela); 1894 } 1895 1896 return TRUE; 1897} 1898 1899/* Find any dynamic relocs that apply to read-only sections. */ 1900 1901static bfd_boolean 1902readonly_dynrelocs (struct elf_link_hash_entry *h, void * inf) 1903{ 1904 struct elf64_x86_64_link_hash_entry *eh; 1905 struct elf64_x86_64_dyn_relocs *p; 1906 1907 if (h->root.type == bfd_link_hash_warning) 1908 h = (struct elf_link_hash_entry *) h->root.u.i.link; 1909 1910 eh = (struct elf64_x86_64_link_hash_entry *) h; 1911 for (p = eh->dyn_relocs; p != NULL; p = p->next) 1912 { 1913 asection *s = p->sec->output_section; 1914 1915 if (s != NULL && (s->flags & SEC_READONLY) != 0) 1916 { 1917 struct bfd_link_info *info = (struct bfd_link_info *) inf; 1918 1919 info->flags |= DF_TEXTREL; 1920 1921 /* Not an error, just cut short the traversal. */ 1922 return FALSE; 1923 } 1924 } 1925 return TRUE; 1926} 1927 1928/* Set the sizes of the dynamic sections. */ 1929 1930static bfd_boolean 1931elf64_x86_64_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED, 1932 struct bfd_link_info *info) 1933{ 1934 struct elf64_x86_64_link_hash_table *htab; 1935 bfd *dynobj; 1936 asection *s; 1937 bfd_boolean relocs; 1938 bfd *ibfd; 1939 1940 htab = elf64_x86_64_hash_table (info); 1941 dynobj = htab->elf.dynobj; 1942 if (dynobj == NULL) 1943 abort (); 1944 1945 if (htab->elf.dynamic_sections_created) 1946 { 1947 /* Set the contents of the .interp section to the interpreter. */ 1948 if (info->executable) 1949 { 1950 s = bfd_get_section_by_name (dynobj, ".interp"); 1951 if (s == NULL) 1952 abort (); 1953 s->size = sizeof ELF_DYNAMIC_INTERPRETER; 1954 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER; 1955 } 1956 } 1957 1958 /* Set up .got offsets for local syms, and space for local dynamic 1959 relocs. */ 1960 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next) 1961 { 1962 bfd_signed_vma *local_got; 1963 bfd_signed_vma *end_local_got; 1964 char *local_tls_type; 1965 bfd_vma *local_tlsdesc_gotent; 1966 bfd_size_type locsymcount; 1967 Elf_Internal_Shdr *symtab_hdr; 1968 asection *srel; 1969 1970 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour) 1971 continue; 1972 1973 for (s = ibfd->sections; s != NULL; s = s->next) 1974 { 1975 struct elf64_x86_64_dyn_relocs *p; 1976 1977 for (p = (struct elf64_x86_64_dyn_relocs *) 1978 (elf_section_data (s)->local_dynrel); 1979 p != NULL; 1980 p = p->next) 1981 { 1982 if (!bfd_is_abs_section (p->sec) 1983 && bfd_is_abs_section (p->sec->output_section)) 1984 { 1985 /* Input section has been discarded, either because 1986 it is a copy of a linkonce section or due to 1987 linker script /DISCARD/, so we'll be discarding 1988 the relocs too. */ 1989 } 1990 else if (p->count != 0) 1991 { 1992 srel = elf_section_data (p->sec)->sreloc; 1993 srel->size += p->count * sizeof (Elf64_External_Rela); 1994 if ((p->sec->output_section->flags & SEC_READONLY) != 0) 1995 info->flags |= DF_TEXTREL; 1996 1997 } 1998 } 1999 } 2000 2001 local_got = elf_local_got_refcounts (ibfd); 2002 if (!local_got) 2003 continue; 2004 2005 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr; 2006 locsymcount = symtab_hdr->sh_info; 2007 end_local_got = local_got + locsymcount; 2008 local_tls_type = elf64_x86_64_local_got_tls_type (ibfd); 2009 local_tlsdesc_gotent = elf64_x86_64_local_tlsdesc_gotent (ibfd); 2010 s = htab->sgot; 2011 srel = htab->srelgot; 2012 for (; local_got < end_local_got; 2013 ++local_got, ++local_tls_type, ++local_tlsdesc_gotent) 2014 { 2015 *local_tlsdesc_gotent = (bfd_vma) -1; 2016 if (*local_got > 0) 2017 { 2018 if (GOT_TLS_GDESC_P (*local_tls_type)) 2019 { 2020 *local_tlsdesc_gotent = htab->sgotplt->size 2021 - elf64_x86_64_compute_jump_table_size (htab); 2022 htab->sgotplt->size += 2 * GOT_ENTRY_SIZE; 2023 *local_got = (bfd_vma) -2; 2024 } 2025 if (! GOT_TLS_GDESC_P (*local_tls_type) 2026 || GOT_TLS_GD_P (*local_tls_type)) 2027 { 2028 *local_got = s->size; 2029 s->size += GOT_ENTRY_SIZE; 2030 if (GOT_TLS_GD_P (*local_tls_type)) 2031 s->size += GOT_ENTRY_SIZE; 2032 } 2033 if (info->shared 2034 || GOT_TLS_GD_ANY_P (*local_tls_type) 2035 || *local_tls_type == GOT_TLS_IE) 2036 { 2037 if (GOT_TLS_GDESC_P (*local_tls_type)) 2038 { 2039 htab->srelplt->size += sizeof (Elf64_External_Rela); 2040 htab->tlsdesc_plt = (bfd_vma) -1; 2041 } 2042 if (! GOT_TLS_GDESC_P (*local_tls_type) 2043 || GOT_TLS_GD_P (*local_tls_type)) 2044 srel->size += sizeof (Elf64_External_Rela); 2045 } 2046 } 2047 else 2048 *local_got = (bfd_vma) -1; 2049 } 2050 } 2051 2052 if (htab->tls_ld_got.refcount > 0) 2053 { 2054 /* Allocate 2 got entries and 1 dynamic reloc for R_X86_64_TLSLD 2055 relocs. */ 2056 htab->tls_ld_got.offset = htab->sgot->size; 2057 htab->sgot->size += 2 * GOT_ENTRY_SIZE; 2058 htab->srelgot->size += sizeof (Elf64_External_Rela); 2059 } 2060 else 2061 htab->tls_ld_got.offset = -1; 2062 2063 /* Allocate global sym .plt and .got entries, and space for global 2064 sym dynamic relocs. */ 2065 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info); 2066 2067 /* For every jump slot reserved in the sgotplt, reloc_count is 2068 incremented. However, when we reserve space for TLS descriptors, 2069 it's not incremented, so in order to compute the space reserved 2070 for them, it suffices to multiply the reloc count by the jump 2071 slot size. */ 2072 if (htab->srelplt) 2073 htab->sgotplt_jump_table_size 2074 = elf64_x86_64_compute_jump_table_size (htab); 2075 2076 if (htab->tlsdesc_plt) 2077 { 2078 /* If we're not using lazy TLS relocations, don't generate the 2079 PLT and GOT entries they require. */ 2080 if ((info->flags & DF_BIND_NOW)) 2081 htab->tlsdesc_plt = 0; 2082 else 2083 { 2084 htab->tlsdesc_got = htab->sgot->size; 2085 htab->sgot->size += GOT_ENTRY_SIZE; 2086 /* Reserve room for the initial entry. 2087 FIXME: we could probably do away with it in this case. */ 2088 if (htab->splt->size == 0) 2089 htab->splt->size += PLT_ENTRY_SIZE; 2090 htab->tlsdesc_plt = htab->splt->size; 2091 htab->splt->size += PLT_ENTRY_SIZE; 2092 } 2093 } 2094 2095 /* We now have determined the sizes of the various dynamic sections. 2096 Allocate memory for them. */ 2097 relocs = FALSE; 2098 for (s = dynobj->sections; s != NULL; s = s->next) 2099 { 2100 if ((s->flags & SEC_LINKER_CREATED) == 0) 2101 continue; 2102 2103 if (s == htab->splt 2104 || s == htab->sgot 2105 || s == htab->sgotplt 2106 || s == htab->sdynbss) 2107 { 2108 /* Strip this section if we don't need it; see the 2109 comment below. */ 2110 } 2111 else if (CONST_STRNEQ (bfd_get_section_name (dynobj, s), ".rela")) 2112 { 2113 if (s->size != 0 && s != htab->srelplt) 2114 relocs = TRUE; 2115 2116 /* We use the reloc_count field as a counter if we need 2117 to copy relocs into the output file. */ 2118 if (s != htab->srelplt) 2119 s->reloc_count = 0; 2120 } 2121 else 2122 { 2123 /* It's not one of our sections, so don't allocate space. */ 2124 continue; 2125 } 2126 2127 if (s->size == 0) 2128 { 2129 /* If we don't need this section, strip it from the 2130 output file. This is mostly to handle .rela.bss and 2131 .rela.plt. We must create both sections in 2132 create_dynamic_sections, because they must be created 2133 before the linker maps input sections to output 2134 sections. The linker does that before 2135 adjust_dynamic_symbol is called, and it is that 2136 function which decides whether anything needs to go 2137 into these sections. */ 2138 2139 s->flags |= SEC_EXCLUDE; 2140 continue; 2141 } 2142 2143 if ((s->flags & SEC_HAS_CONTENTS) == 0) 2144 continue; 2145 2146 /* Allocate memory for the section contents. We use bfd_zalloc 2147 here in case unused entries are not reclaimed before the 2148 section's contents are written out. This should not happen, 2149 but this way if it does, we get a R_X86_64_NONE reloc instead 2150 of garbage. */ 2151 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->size); 2152 if (s->contents == NULL) 2153 return FALSE; 2154 } 2155 2156 if (htab->elf.dynamic_sections_created) 2157 { 2158 /* Add some entries to the .dynamic section. We fill in the 2159 values later, in elf64_x86_64_finish_dynamic_sections, but we 2160 must add the entries now so that we get the correct size for 2161 the .dynamic section. The DT_DEBUG entry is filled in by the 2162 dynamic linker and used by the debugger. */ 2163#define add_dynamic_entry(TAG, VAL) \ 2164 _bfd_elf_add_dynamic_entry (info, TAG, VAL) 2165 2166 if (info->executable) 2167 { 2168 if (!add_dynamic_entry (DT_DEBUG, 0)) 2169 return FALSE; 2170 } 2171 2172 if (htab->splt->size != 0) 2173 { 2174 if (!add_dynamic_entry (DT_PLTGOT, 0) 2175 || !add_dynamic_entry (DT_PLTRELSZ, 0) 2176 || !add_dynamic_entry (DT_PLTREL, DT_RELA) 2177 || !add_dynamic_entry (DT_JMPREL, 0)) 2178 return FALSE; 2179 2180 if (htab->tlsdesc_plt 2181 && (!add_dynamic_entry (DT_TLSDESC_PLT, 0) 2182 || !add_dynamic_entry (DT_TLSDESC_GOT, 0))) 2183 return FALSE; 2184 } 2185 2186 if (relocs) 2187 { 2188 if (!add_dynamic_entry (DT_RELA, 0) 2189 || !add_dynamic_entry (DT_RELASZ, 0) 2190 || !add_dynamic_entry (DT_RELAENT, sizeof (Elf64_External_Rela))) 2191 return FALSE; 2192 2193 /* If any dynamic relocs apply to a read-only section, 2194 then we need a DT_TEXTREL entry. */ 2195 if ((info->flags & DF_TEXTREL) == 0) 2196 elf_link_hash_traverse (&htab->elf, readonly_dynrelocs, 2197 (PTR) info); 2198 2199 if ((info->flags & DF_TEXTREL) != 0) 2200 { 2201 if (!add_dynamic_entry (DT_TEXTREL, 0)) 2202 return FALSE; 2203 } 2204 } 2205 } 2206#undef add_dynamic_entry 2207 2208 return TRUE; 2209} 2210 2211static bfd_boolean 2212elf64_x86_64_always_size_sections (bfd *output_bfd, 2213 struct bfd_link_info *info) 2214{ 2215 asection *tls_sec = elf_hash_table (info)->tls_sec; 2216 2217 if (tls_sec) 2218 { 2219 struct elf_link_hash_entry *tlsbase; 2220 2221 tlsbase = elf_link_hash_lookup (elf_hash_table (info), 2222 "_TLS_MODULE_BASE_", 2223 FALSE, FALSE, FALSE); 2224 2225 if (tlsbase && tlsbase->type == STT_TLS) 2226 { 2227 struct bfd_link_hash_entry *bh = NULL; 2228 const struct elf_backend_data *bed 2229 = get_elf_backend_data (output_bfd); 2230 2231 if (!(_bfd_generic_link_add_one_symbol 2232 (info, output_bfd, "_TLS_MODULE_BASE_", BSF_LOCAL, 2233 tls_sec, 0, NULL, FALSE, 2234 bed->collect, &bh))) 2235 return FALSE; 2236 tlsbase = (struct elf_link_hash_entry *)bh; 2237 tlsbase->def_regular = 1; 2238 tlsbase->other = STV_HIDDEN; 2239 (*bed->elf_backend_hide_symbol) (info, tlsbase, TRUE); 2240 } 2241 } 2242 2243 return TRUE; 2244} 2245 2246/* Return the base VMA address which should be subtracted from real addresses 2247 when resolving @dtpoff relocation. 2248 This is PT_TLS segment p_vaddr. */ 2249 2250static bfd_vma 2251dtpoff_base (struct bfd_link_info *info) 2252{ 2253 /* If tls_sec is NULL, we should have signalled an error already. */ 2254 if (elf_hash_table (info)->tls_sec == NULL) 2255 return 0; 2256 return elf_hash_table (info)->tls_sec->vma; 2257} 2258 2259/* Return the relocation value for @tpoff relocation 2260 if STT_TLS virtual address is ADDRESS. */ 2261 2262static bfd_vma 2263tpoff (struct bfd_link_info *info, bfd_vma address) 2264{ 2265 struct elf_link_hash_table *htab = elf_hash_table (info); 2266 2267 /* If tls_segment is NULL, we should have signalled an error already. */ 2268 if (htab->tls_sec == NULL) 2269 return 0; 2270 return address - htab->tls_size - htab->tls_sec->vma; 2271} 2272 2273/* Is the instruction before OFFSET in CONTENTS a 32bit relative 2274 branch? */ 2275 2276static bfd_boolean 2277is_32bit_relative_branch (bfd_byte *contents, bfd_vma offset) 2278{ 2279 /* Opcode Instruction 2280 0xe8 call 2281 0xe9 jump 2282 0x0f 0x8x conditional jump */ 2283 return ((offset > 0 2284 && (contents [offset - 1] == 0xe8 2285 || contents [offset - 1] == 0xe9)) 2286 || (offset > 1 2287 && contents [offset - 2] == 0x0f 2288 && (contents [offset - 1] & 0xf0) == 0x80)); 2289} 2290 2291/* Relocate an x86_64 ELF section. */ 2292 2293static bfd_boolean 2294elf64_x86_64_relocate_section (bfd *output_bfd, struct bfd_link_info *info, 2295 bfd *input_bfd, asection *input_section, 2296 bfd_byte *contents, Elf_Internal_Rela *relocs, 2297 Elf_Internal_Sym *local_syms, 2298 asection **local_sections) 2299{ 2300 struct elf64_x86_64_link_hash_table *htab; 2301 Elf_Internal_Shdr *symtab_hdr; 2302 struct elf_link_hash_entry **sym_hashes; 2303 bfd_vma *local_got_offsets; 2304 bfd_vma *local_tlsdesc_gotents; 2305 Elf_Internal_Rela *rel; 2306 Elf_Internal_Rela *relend; 2307 2308 htab = elf64_x86_64_hash_table (info); 2309 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr; 2310 sym_hashes = elf_sym_hashes (input_bfd); 2311 local_got_offsets = elf_local_got_offsets (input_bfd); 2312 local_tlsdesc_gotents = elf64_x86_64_local_tlsdesc_gotent (input_bfd); 2313 2314 rel = relocs; 2315 relend = relocs + input_section->reloc_count; 2316 for (; rel < relend; rel++) 2317 { 2318 unsigned int r_type; 2319 reloc_howto_type *howto; 2320 unsigned long r_symndx; 2321 struct elf_link_hash_entry *h; 2322 Elf_Internal_Sym *sym; 2323 asection *sec; 2324 bfd_vma off, offplt; 2325 bfd_vma relocation; 2326 bfd_boolean unresolved_reloc; 2327 bfd_reloc_status_type r; 2328 int tls_type; 2329 2330 r_type = ELF64_R_TYPE (rel->r_info); 2331 if (r_type == (int) R_X86_64_GNU_VTINHERIT 2332 || r_type == (int) R_X86_64_GNU_VTENTRY) 2333 continue; 2334 2335 if (r_type >= R_X86_64_max) 2336 { 2337 bfd_set_error (bfd_error_bad_value); 2338 return FALSE; 2339 } 2340 2341 howto = x86_64_elf_howto_table + r_type; 2342 r_symndx = ELF64_R_SYM (rel->r_info); 2343 h = NULL; 2344 sym = NULL; 2345 sec = NULL; 2346 unresolved_reloc = FALSE; 2347 if (r_symndx < symtab_hdr->sh_info) 2348 { 2349 sym = local_syms + r_symndx; 2350 sec = local_sections[r_symndx]; 2351 2352 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel); 2353 } 2354 else 2355 { 2356 bfd_boolean warned; 2357 2358 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel, 2359 r_symndx, symtab_hdr, sym_hashes, 2360 h, sec, relocation, 2361 unresolved_reloc, warned); 2362 } 2363 2364 if (sec != NULL && elf_discarded_section (sec)) 2365 { 2366 /* For relocs against symbols from removed linkonce sections, 2367 or sections discarded by a linker script, we just want the 2368 section contents zeroed. Avoid any special processing. */ 2369 _bfd_clear_contents (howto, input_bfd, contents + rel->r_offset); 2370 rel->r_info = 0; 2371 rel->r_addend = 0; 2372 continue; 2373 } 2374 2375 if (info->relocatable) 2376 continue; 2377 2378 /* When generating a shared object, the relocations handled here are 2379 copied into the output file to be resolved at run time. */ 2380 switch (r_type) 2381 { 2382 asection *base_got; 2383 case R_X86_64_GOT32: 2384 case R_X86_64_GOT64: 2385 /* Relocation is to the entry for this symbol in the global 2386 offset table. */ 2387 case R_X86_64_GOTPCREL: 2388 case R_X86_64_GOTPCREL64: 2389 /* Use global offset table entry as symbol value. */ 2390 case R_X86_64_GOTPLT64: 2391 /* This is the same as GOT64 for relocation purposes, but 2392 indicates the existence of a PLT entry. The difficulty is, 2393 that we must calculate the GOT slot offset from the PLT 2394 offset, if this symbol got a PLT entry (it was global). 2395 Additionally if it's computed from the PLT entry, then that 2396 GOT offset is relative to .got.plt, not to .got. */ 2397 base_got = htab->sgot; 2398 2399 if (htab->sgot == NULL) 2400 abort (); 2401 2402 if (h != NULL) 2403 { 2404 bfd_boolean dyn; 2405 2406 off = h->got.offset; 2407 if (h->needs_plt 2408 && h->plt.offset != (bfd_vma)-1 2409 && off == (bfd_vma)-1) 2410 { 2411 /* We can't use h->got.offset here to save 2412 state, or even just remember the offset, as 2413 finish_dynamic_symbol would use that as offset into 2414 .got. */ 2415 bfd_vma plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1; 2416 off = (plt_index + 3) * GOT_ENTRY_SIZE; 2417 base_got = htab->sgotplt; 2418 } 2419 2420 dyn = htab->elf.dynamic_sections_created; 2421 2422 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info->shared, h) 2423 || (info->shared 2424 && SYMBOL_REFERENCES_LOCAL (info, h)) 2425 || (ELF_ST_VISIBILITY (h->other) 2426 && h->root.type == bfd_link_hash_undefweak)) 2427 { 2428 /* This is actually a static link, or it is a -Bsymbolic 2429 link and the symbol is defined locally, or the symbol 2430 was forced to be local because of a version file. We 2431 must initialize this entry in the global offset table. 2432 Since the offset must always be a multiple of 8, we 2433 use the least significant bit to record whether we 2434 have initialized it already. 2435 2436 When doing a dynamic link, we create a .rela.got 2437 relocation entry to initialize the value. This is 2438 done in the finish_dynamic_symbol routine. */ 2439 if ((off & 1) != 0) 2440 off &= ~1; 2441 else 2442 { 2443 bfd_put_64 (output_bfd, relocation, 2444 base_got->contents + off); 2445 /* Note that this is harmless for the GOTPLT64 case, 2446 as -1 | 1 still is -1. */ 2447 h->got.offset |= 1; 2448 } 2449 } 2450 else 2451 unresolved_reloc = FALSE; 2452 } 2453 else 2454 { 2455 if (local_got_offsets == NULL) 2456 abort (); 2457 2458 off = local_got_offsets[r_symndx]; 2459 2460 /* The offset must always be a multiple of 8. We use 2461 the least significant bit to record whether we have 2462 already generated the necessary reloc. */ 2463 if ((off & 1) != 0) 2464 off &= ~1; 2465 else 2466 { 2467 bfd_put_64 (output_bfd, relocation, 2468 base_got->contents + off); 2469 2470 if (info->shared) 2471 { 2472 asection *s; 2473 Elf_Internal_Rela outrel; 2474 bfd_byte *loc; 2475 2476 /* We need to generate a R_X86_64_RELATIVE reloc 2477 for the dynamic linker. */ 2478 s = htab->srelgot; 2479 if (s == NULL) 2480 abort (); 2481 2482 outrel.r_offset = (base_got->output_section->vma 2483 + base_got->output_offset 2484 + off); 2485 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE); 2486 outrel.r_addend = relocation; 2487 loc = s->contents; 2488 loc += s->reloc_count++ * sizeof (Elf64_External_Rela); 2489 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc); 2490 } 2491 2492 local_got_offsets[r_symndx] |= 1; 2493 } 2494 } 2495 2496 if (off >= (bfd_vma) -2) 2497 abort (); 2498 2499 relocation = base_got->output_section->vma 2500 + base_got->output_offset + off; 2501 if (r_type != R_X86_64_GOTPCREL && r_type != R_X86_64_GOTPCREL64) 2502 relocation -= htab->sgotplt->output_section->vma 2503 - htab->sgotplt->output_offset; 2504 2505 break; 2506 2507 case R_X86_64_GOTOFF64: 2508 /* Relocation is relative to the start of the global offset 2509 table. */ 2510 2511 /* Check to make sure it isn't a protected function symbol 2512 for shared library since it may not be local when used 2513 as function address. */ 2514 if (info->shared 2515 && h 2516 && h->def_regular 2517 && h->type == STT_FUNC 2518 && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED) 2519 { 2520 (*_bfd_error_handler) 2521 (_("%B: relocation R_X86_64_GOTOFF64 against protected function `%s' can not be used when making a shared object"), 2522 input_bfd, h->root.root.string); 2523 bfd_set_error (bfd_error_bad_value); 2524 return FALSE; 2525 } 2526 2527 /* Note that sgot is not involved in this 2528 calculation. We always want the start of .got.plt. If we 2529 defined _GLOBAL_OFFSET_TABLE_ in a different way, as is 2530 permitted by the ABI, we might have to change this 2531 calculation. */ 2532 relocation -= htab->sgotplt->output_section->vma 2533 + htab->sgotplt->output_offset; 2534 break; 2535 2536 case R_X86_64_GOTPC32: 2537 case R_X86_64_GOTPC64: 2538 /* Use global offset table as symbol value. */ 2539 relocation = htab->sgotplt->output_section->vma 2540 + htab->sgotplt->output_offset; 2541 unresolved_reloc = FALSE; 2542 break; 2543 2544 case R_X86_64_PLTOFF64: 2545 /* Relocation is PLT entry relative to GOT. For local 2546 symbols it's the symbol itself relative to GOT. */ 2547 if (h != NULL 2548 /* See PLT32 handling. */ 2549 && h->plt.offset != (bfd_vma) -1 2550 && htab->splt != NULL) 2551 { 2552 relocation = (htab->splt->output_section->vma 2553 + htab->splt->output_offset 2554 + h->plt.offset); 2555 unresolved_reloc = FALSE; 2556 } 2557 2558 relocation -= htab->sgotplt->output_section->vma 2559 + htab->sgotplt->output_offset; 2560 break; 2561 2562 case R_X86_64_PLT32: 2563 /* Relocation is to the entry for this symbol in the 2564 procedure linkage table. */ 2565 2566 /* Resolve a PLT32 reloc against a local symbol directly, 2567 without using the procedure linkage table. */ 2568 if (h == NULL) 2569 break; 2570 2571 if (h->plt.offset == (bfd_vma) -1 2572 || htab->splt == NULL) 2573 { 2574 /* We didn't make a PLT entry for this symbol. This 2575 happens when statically linking PIC code, or when 2576 using -Bsymbolic. */ 2577 break; 2578 } 2579 2580 relocation = (htab->splt->output_section->vma 2581 + htab->splt->output_offset 2582 + h->plt.offset); 2583 unresolved_reloc = FALSE; 2584 break; 2585 2586 case R_X86_64_PC8: 2587 case R_X86_64_PC16: 2588 case R_X86_64_PC32: 2589 if (info->shared 2590 && !SYMBOL_REFERENCES_LOCAL (info, h) 2591 && (input_section->flags & SEC_ALLOC) != 0 2592 && (input_section->flags & SEC_READONLY) != 0 2593 && (!h->def_regular 2594 || r_type != R_X86_64_PC32 2595 || h->type != STT_FUNC 2596 || ELF_ST_VISIBILITY (h->other) != STV_PROTECTED 2597 || !is_32bit_relative_branch (contents, 2598 rel->r_offset))) 2599 { 2600 if (h->def_regular 2601 && r_type == R_X86_64_PC32 2602 && h->type == STT_FUNC 2603 && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED) 2604 (*_bfd_error_handler) 2605 (_("%B: relocation R_X86_64_PC32 against protected function `%s' can not be used when making a shared object"), 2606 input_bfd, h->root.root.string); 2607 else 2608 (*_bfd_error_handler) 2609 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"), 2610 input_bfd, x86_64_elf_howto_table[r_type].name, 2611 h->root.root.string); 2612 bfd_set_error (bfd_error_bad_value); 2613 return FALSE; 2614 } 2615 /* Fall through. */ 2616 2617 case R_X86_64_8: 2618 case R_X86_64_16: 2619 case R_X86_64_32: 2620 case R_X86_64_PC64: 2621 case R_X86_64_64: 2622 /* FIXME: The ABI says the linker should make sure the value is 2623 the same when it's zeroextended to 64 bit. */ 2624 2625 if ((input_section->flags & SEC_ALLOC) == 0) 2626 break; 2627 2628 if ((info->shared 2629 && (h == NULL 2630 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT 2631 || h->root.type != bfd_link_hash_undefweak) 2632 && ((r_type != R_X86_64_PC8 2633 && r_type != R_X86_64_PC16 2634 && r_type != R_X86_64_PC32 2635 && r_type != R_X86_64_PC64) 2636 || !SYMBOL_CALLS_LOCAL (info, h))) 2637 || (ELIMINATE_COPY_RELOCS 2638 && !info->shared 2639 && h != NULL 2640 && h->dynindx != -1 2641 && !h->non_got_ref 2642 && ((h->def_dynamic 2643 && !h->def_regular) 2644 || h->root.type == bfd_link_hash_undefweak 2645 || h->root.type == bfd_link_hash_undefined))) 2646 { 2647 Elf_Internal_Rela outrel; 2648 bfd_byte *loc; 2649 bfd_boolean skip, relocate; 2650 asection *sreloc; 2651 2652 /* When generating a shared object, these relocations 2653 are copied into the output file to be resolved at run 2654 time. */ 2655 skip = FALSE; 2656 relocate = FALSE; 2657 2658 outrel.r_offset = 2659 _bfd_elf_section_offset (output_bfd, info, input_section, 2660 rel->r_offset); 2661 if (outrel.r_offset == (bfd_vma) -1) 2662 skip = TRUE; 2663 else if (outrel.r_offset == (bfd_vma) -2) 2664 skip = TRUE, relocate = TRUE; 2665 2666 outrel.r_offset += (input_section->output_section->vma 2667 + input_section->output_offset); 2668 2669 if (skip) 2670 memset (&outrel, 0, sizeof outrel); 2671 2672 /* h->dynindx may be -1 if this symbol was marked to 2673 become local. */ 2674 else if (h != NULL 2675 && h->dynindx != -1 2676 && (r_type == R_X86_64_PC8 2677 || r_type == R_X86_64_PC16 2678 || r_type == R_X86_64_PC32 2679 || r_type == R_X86_64_PC64 2680 || !info->shared 2681 || !SYMBOLIC_BIND (info, h) 2682 || !h->def_regular)) 2683 { 2684 outrel.r_info = ELF64_R_INFO (h->dynindx, r_type); 2685 outrel.r_addend = rel->r_addend; 2686 } 2687 else 2688 { 2689 /* This symbol is local, or marked to become local. */ 2690 if (r_type == R_X86_64_64) 2691 { 2692 relocate = TRUE; 2693 outrel.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE); 2694 outrel.r_addend = relocation + rel->r_addend; 2695 } 2696 else 2697 { 2698 long sindx; 2699 2700 if (bfd_is_abs_section (sec)) 2701 sindx = 0; 2702 else if (sec == NULL || sec->owner == NULL) 2703 { 2704 bfd_set_error (bfd_error_bad_value); 2705 return FALSE; 2706 } 2707 else 2708 { 2709 asection *osec; 2710 2711 /* We are turning this relocation into one 2712 against a section symbol. It would be 2713 proper to subtract the symbol's value, 2714 osec->vma, from the emitted reloc addend, 2715 but ld.so expects buggy relocs. */ 2716 osec = sec->output_section; 2717 sindx = elf_section_data (osec)->dynindx; 2718 if (sindx == 0) 2719 { 2720 asection *oi = htab->elf.text_index_section; 2721 sindx = elf_section_data (oi)->dynindx; 2722 } 2723 BFD_ASSERT (sindx != 0); 2724 } 2725 2726 outrel.r_info = ELF64_R_INFO (sindx, r_type); 2727 outrel.r_addend = relocation + rel->r_addend; 2728 } 2729 } 2730 2731 sreloc = elf_section_data (input_section)->sreloc; 2732 if (sreloc == NULL) 2733 abort (); 2734 2735 loc = sreloc->contents; 2736 loc += sreloc->reloc_count++ * sizeof (Elf64_External_Rela); 2737 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc); 2738 2739 /* If this reloc is against an external symbol, we do 2740 not want to fiddle with the addend. Otherwise, we 2741 need to include the symbol value so that it becomes 2742 an addend for the dynamic reloc. */ 2743 if (! relocate) 2744 continue; 2745 } 2746 2747 break; 2748 2749 case R_X86_64_TLSGD: 2750 case R_X86_64_GOTPC32_TLSDESC: 2751 case R_X86_64_TLSDESC_CALL: 2752 case R_X86_64_GOTTPOFF: 2753 tls_type = GOT_UNKNOWN; 2754 if (h == NULL && local_got_offsets) 2755 tls_type = elf64_x86_64_local_got_tls_type (input_bfd) [r_symndx]; 2756 else if (h != NULL) 2757 tls_type = elf64_x86_64_hash_entry (h)->tls_type; 2758 2759 if (! elf64_x86_64_tls_transition (info, input_bfd, 2760 input_section, contents, 2761 symtab_hdr, sym_hashes, 2762 &r_type, tls_type, rel, 2763 relend, h)) 2764 return FALSE; 2765 2766 if (r_type == R_X86_64_TPOFF32) 2767 { 2768 bfd_vma roff = rel->r_offset; 2769 2770 BFD_ASSERT (! unresolved_reloc); 2771 2772 if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSGD) 2773 { 2774 /* GD->LE transition. 2775 .byte 0x66; leaq foo@tlsgd(%rip), %rdi 2776 .word 0x6666; rex64; call __tls_get_addr 2777 Change it into: 2778 movq %fs:0, %rax 2779 leaq foo@tpoff(%rax), %rax */ 2780 memcpy (contents + roff - 4, 2781 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0", 2782 16); 2783 bfd_put_32 (output_bfd, tpoff (info, relocation), 2784 contents + roff + 8); 2785 /* Skip R_X86_64_PC32/R_X86_64_PLT32. */ 2786 rel++; 2787 continue; 2788 } 2789 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_GOTPC32_TLSDESC) 2790 { 2791 /* GDesc -> LE transition. 2792 It's originally something like: 2793 leaq x@tlsdesc(%rip), %rax 2794 2795 Change it to: 2796 movl $x@tpoff, %rax 2797 */ 2798 2799 unsigned int val, type, type2; 2800 2801 type = bfd_get_8 (input_bfd, contents + roff - 3); 2802 type2 = bfd_get_8 (input_bfd, contents + roff - 2); 2803 val = bfd_get_8 (input_bfd, contents + roff - 1); 2804 bfd_put_8 (output_bfd, 0x48 | ((type >> 2) & 1), 2805 contents + roff - 3); 2806 bfd_put_8 (output_bfd, 0xc7, contents + roff - 2); 2807 bfd_put_8 (output_bfd, 0xc0 | ((val >> 3) & 7), 2808 contents + roff - 1); 2809 bfd_put_32 (output_bfd, tpoff (info, relocation), 2810 contents + roff); 2811 continue; 2812 } 2813 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSDESC_CALL) 2814 { 2815 /* GDesc -> LE transition. 2816 It's originally: 2817 call *(%rax) 2818 Turn it into: 2819 xchg %ax,%ax. */ 2820 bfd_put_8 (output_bfd, 0x66, contents + roff); 2821 bfd_put_8 (output_bfd, 0x90, contents + roff + 1); 2822 continue; 2823 } 2824 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_GOTTPOFF) 2825 { 2826 /* IE->LE transition: 2827 Originally it can be one of: 2828 movq foo@gottpoff(%rip), %reg 2829 addq foo@gottpoff(%rip), %reg 2830 We change it into: 2831 movq $foo, %reg 2832 leaq foo(%reg), %reg 2833 addq $foo, %reg. */ 2834 2835 unsigned int val, type, reg; 2836 2837 val = bfd_get_8 (input_bfd, contents + roff - 3); 2838 type = bfd_get_8 (input_bfd, contents + roff - 2); 2839 reg = bfd_get_8 (input_bfd, contents + roff - 1); 2840 reg >>= 3; 2841 if (type == 0x8b) 2842 { 2843 /* movq */ 2844 if (val == 0x4c) 2845 bfd_put_8 (output_bfd, 0x49, 2846 contents + roff - 3); 2847 bfd_put_8 (output_bfd, 0xc7, 2848 contents + roff - 2); 2849 bfd_put_8 (output_bfd, 0xc0 | reg, 2850 contents + roff - 1); 2851 } 2852 else if (reg == 4) 2853 { 2854 /* addq -> addq - addressing with %rsp/%r12 is 2855 special */ 2856 if (val == 0x4c) 2857 bfd_put_8 (output_bfd, 0x49, 2858 contents + roff - 3); 2859 bfd_put_8 (output_bfd, 0x81, 2860 contents + roff - 2); 2861 bfd_put_8 (output_bfd, 0xc0 | reg, 2862 contents + roff - 1); 2863 } 2864 else 2865 { 2866 /* addq -> leaq */ 2867 if (val == 0x4c) 2868 bfd_put_8 (output_bfd, 0x4d, 2869 contents + roff - 3); 2870 bfd_put_8 (output_bfd, 0x8d, 2871 contents + roff - 2); 2872 bfd_put_8 (output_bfd, 0x80 | reg | (reg << 3), 2873 contents + roff - 1); 2874 } 2875 bfd_put_32 (output_bfd, tpoff (info, relocation), 2876 contents + roff); 2877 continue; 2878 } 2879 else 2880 BFD_ASSERT (FALSE); 2881 } 2882 2883 if (htab->sgot == NULL) 2884 abort (); 2885 2886 if (h != NULL) 2887 { 2888 off = h->got.offset; 2889 offplt = elf64_x86_64_hash_entry (h)->tlsdesc_got; 2890 } 2891 else 2892 { 2893 if (local_got_offsets == NULL) 2894 abort (); 2895 2896 off = local_got_offsets[r_symndx]; 2897 offplt = local_tlsdesc_gotents[r_symndx]; 2898 } 2899 2900 if ((off & 1) != 0) 2901 off &= ~1; 2902 else 2903 { 2904 Elf_Internal_Rela outrel; 2905 bfd_byte *loc; 2906 int dr_type, indx; 2907 asection *sreloc; 2908 2909 if (htab->srelgot == NULL) 2910 abort (); 2911 2912 indx = h && h->dynindx != -1 ? h->dynindx : 0; 2913 2914 if (GOT_TLS_GDESC_P (tls_type)) 2915 { 2916 outrel.r_info = ELF64_R_INFO (indx, R_X86_64_TLSDESC); 2917 BFD_ASSERT (htab->sgotplt_jump_table_size + offplt 2918 + 2 * GOT_ENTRY_SIZE <= htab->sgotplt->size); 2919 outrel.r_offset = (htab->sgotplt->output_section->vma 2920 + htab->sgotplt->output_offset 2921 + offplt 2922 + htab->sgotplt_jump_table_size); 2923 sreloc = htab->srelplt; 2924 loc = sreloc->contents; 2925 loc += sreloc->reloc_count++ 2926 * sizeof (Elf64_External_Rela); 2927 BFD_ASSERT (loc + sizeof (Elf64_External_Rela) 2928 <= sreloc->contents + sreloc->size); 2929 if (indx == 0) 2930 outrel.r_addend = relocation - dtpoff_base (info); 2931 else 2932 outrel.r_addend = 0; 2933 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc); 2934 } 2935 2936 sreloc = htab->srelgot; 2937 2938 outrel.r_offset = (htab->sgot->output_section->vma 2939 + htab->sgot->output_offset + off); 2940 2941 if (GOT_TLS_GD_P (tls_type)) 2942 dr_type = R_X86_64_DTPMOD64; 2943 else if (GOT_TLS_GDESC_P (tls_type)) 2944 goto dr_done; 2945 else 2946 dr_type = R_X86_64_TPOFF64; 2947 2948 bfd_put_64 (output_bfd, 0, htab->sgot->contents + off); 2949 outrel.r_addend = 0; 2950 if ((dr_type == R_X86_64_TPOFF64 2951 || dr_type == R_X86_64_TLSDESC) && indx == 0) 2952 outrel.r_addend = relocation - dtpoff_base (info); 2953 outrel.r_info = ELF64_R_INFO (indx, dr_type); 2954 2955 loc = sreloc->contents; 2956 loc += sreloc->reloc_count++ * sizeof (Elf64_External_Rela); 2957 BFD_ASSERT (loc + sizeof (Elf64_External_Rela) 2958 <= sreloc->contents + sreloc->size); 2959 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc); 2960 2961 if (GOT_TLS_GD_P (tls_type)) 2962 { 2963 if (indx == 0) 2964 { 2965 BFD_ASSERT (! unresolved_reloc); 2966 bfd_put_64 (output_bfd, 2967 relocation - dtpoff_base (info), 2968 htab->sgot->contents + off + GOT_ENTRY_SIZE); 2969 } 2970 else 2971 { 2972 bfd_put_64 (output_bfd, 0, 2973 htab->sgot->contents + off + GOT_ENTRY_SIZE); 2974 outrel.r_info = ELF64_R_INFO (indx, 2975 R_X86_64_DTPOFF64); 2976 outrel.r_offset += GOT_ENTRY_SIZE; 2977 sreloc->reloc_count++; 2978 loc += sizeof (Elf64_External_Rela); 2979 BFD_ASSERT (loc + sizeof (Elf64_External_Rela) 2980 <= sreloc->contents + sreloc->size); 2981 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc); 2982 } 2983 } 2984 2985 dr_done: 2986 if (h != NULL) 2987 h->got.offset |= 1; 2988 else 2989 local_got_offsets[r_symndx] |= 1; 2990 } 2991 2992 if (off >= (bfd_vma) -2 2993 && ! GOT_TLS_GDESC_P (tls_type)) 2994 abort (); 2995 if (r_type == ELF64_R_TYPE (rel->r_info)) 2996 { 2997 if (r_type == R_X86_64_GOTPC32_TLSDESC 2998 || r_type == R_X86_64_TLSDESC_CALL) 2999 relocation = htab->sgotplt->output_section->vma 3000 + htab->sgotplt->output_offset 3001 + offplt + htab->sgotplt_jump_table_size; 3002 else 3003 relocation = htab->sgot->output_section->vma 3004 + htab->sgot->output_offset + off; 3005 unresolved_reloc = FALSE; 3006 } 3007 else 3008 { 3009 bfd_vma roff = rel->r_offset; 3010 3011 if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSGD) 3012 { 3013 /* GD->IE transition. 3014 .byte 0x66; leaq foo@tlsgd(%rip), %rdi 3015 .word 0x6666; rex64; call __tls_get_addr@plt 3016 Change it into: 3017 movq %fs:0, %rax 3018 addq foo@gottpoff(%rip), %rax */ 3019 memcpy (contents + roff - 4, 3020 "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0", 3021 16); 3022 3023 relocation = (htab->sgot->output_section->vma 3024 + htab->sgot->output_offset + off 3025 - roff 3026 - input_section->output_section->vma 3027 - input_section->output_offset 3028 - 12); 3029 bfd_put_32 (output_bfd, relocation, 3030 contents + roff + 8); 3031 /* Skip R_X86_64_PLT32. */ 3032 rel++; 3033 continue; 3034 } 3035 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_GOTPC32_TLSDESC) 3036 { 3037 /* GDesc -> IE transition. 3038 It's originally something like: 3039 leaq x@tlsdesc(%rip), %rax 3040 3041 Change it to: 3042 movq x@gottpoff(%rip), %rax # before xchg %ax,%ax 3043 */ 3044 3045 unsigned int val, type, type2; 3046 3047 type = bfd_get_8 (input_bfd, contents + roff - 3); 3048 type2 = bfd_get_8 (input_bfd, contents + roff - 2); 3049 val = bfd_get_8 (input_bfd, contents + roff - 1); 3050 3051 /* Now modify the instruction as appropriate. To 3052 turn a leaq into a movq in the form we use it, it 3053 suffices to change the second byte from 0x8d to 3054 0x8b. */ 3055 bfd_put_8 (output_bfd, 0x8b, contents + roff - 2); 3056 3057 bfd_put_32 (output_bfd, 3058 htab->sgot->output_section->vma 3059 + htab->sgot->output_offset + off 3060 - rel->r_offset 3061 - input_section->output_section->vma 3062 - input_section->output_offset 3063 - 4, 3064 contents + roff); 3065 continue; 3066 } 3067 else if (ELF64_R_TYPE (rel->r_info) == R_X86_64_TLSDESC_CALL) 3068 { 3069 /* GDesc -> IE transition. 3070 It's originally: 3071 call *(%rax) 3072 3073 Change it to: 3074 xchg %ax,%ax. */ 3075 3076 unsigned int val, type; 3077 3078 type = bfd_get_8 (input_bfd, contents + roff); 3079 val = bfd_get_8 (input_bfd, contents + roff + 1); 3080 bfd_put_8 (output_bfd, 0x66, contents + roff); 3081 bfd_put_8 (output_bfd, 0x90, contents + roff + 1); 3082 continue; 3083 } 3084 else 3085 BFD_ASSERT (FALSE); 3086 } 3087 break; 3088 3089 case R_X86_64_TLSLD: 3090 if (! elf64_x86_64_tls_transition (info, input_bfd, 3091 input_section, contents, 3092 symtab_hdr, sym_hashes, 3093 &r_type, GOT_UNKNOWN, 3094 rel, relend, h)) 3095 return FALSE; 3096 3097 if (r_type != R_X86_64_TLSLD) 3098 { 3099 /* LD->LE transition: 3100 leaq foo@tlsld(%rip), %rdi; call __tls_get_addr. 3101 We change it into: 3102 .word 0x6666; .byte 0x66; movl %fs:0, %rax. */ 3103 3104 BFD_ASSERT (r_type == R_X86_64_TPOFF32); 3105 memcpy (contents + rel->r_offset - 3, 3106 "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0", 12); 3107 /* Skip R_X86_64_PC32/R_X86_64_PLT32. */ 3108 rel++; 3109 continue; 3110 } 3111 3112 if (htab->sgot == NULL) 3113 abort (); 3114 3115 off = htab->tls_ld_got.offset; 3116 if (off & 1) 3117 off &= ~1; 3118 else 3119 { 3120 Elf_Internal_Rela outrel; 3121 bfd_byte *loc; 3122 3123 if (htab->srelgot == NULL) 3124 abort (); 3125 3126 outrel.r_offset = (htab->sgot->output_section->vma 3127 + htab->sgot->output_offset + off); 3128 3129 bfd_put_64 (output_bfd, 0, 3130 htab->sgot->contents + off); 3131 bfd_put_64 (output_bfd, 0, 3132 htab->sgot->contents + off + GOT_ENTRY_SIZE); 3133 outrel.r_info = ELF64_R_INFO (0, R_X86_64_DTPMOD64); 3134 outrel.r_addend = 0; 3135 loc = htab->srelgot->contents; 3136 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela); 3137 bfd_elf64_swap_reloca_out (output_bfd, &outrel, loc); 3138 htab->tls_ld_got.offset |= 1; 3139 } 3140 relocation = htab->sgot->output_section->vma 3141 + htab->sgot->output_offset + off; 3142 unresolved_reloc = FALSE; 3143 break; 3144 3145 case R_X86_64_DTPOFF32: 3146 if (info->shared || (input_section->flags & SEC_CODE) == 0) 3147 relocation -= dtpoff_base (info); 3148 else 3149 relocation = tpoff (info, relocation); 3150 break; 3151 3152 case R_X86_64_TPOFF32: 3153 BFD_ASSERT (! info->shared); 3154 relocation = tpoff (info, relocation); 3155 break; 3156 3157 default: 3158 break; 3159 } 3160 3161 /* Dynamic relocs are not propagated for SEC_DEBUGGING sections 3162 because such sections are not SEC_ALLOC and thus ld.so will 3163 not process them. */ 3164 if (unresolved_reloc 3165 && !((input_section->flags & SEC_DEBUGGING) != 0 3166 && h->def_dynamic)) 3167 (*_bfd_error_handler) 3168 (_("%B(%A+0x%lx): unresolvable %s relocation against symbol `%s'"), 3169 input_bfd, 3170 input_section, 3171 (long) rel->r_offset, 3172 howto->name, 3173 h->root.root.string); 3174 3175 r = _bfd_final_link_relocate (howto, input_bfd, input_section, 3176 contents, rel->r_offset, 3177 relocation, rel->r_addend); 3178 3179 if (r != bfd_reloc_ok) 3180 { 3181 const char *name; 3182 3183 if (h != NULL) 3184 name = h->root.root.string; 3185 else 3186 { 3187 name = bfd_elf_string_from_elf_section (input_bfd, 3188 symtab_hdr->sh_link, 3189 sym->st_name); 3190 if (name == NULL) 3191 return FALSE; 3192 if (*name == '\0') 3193 name = bfd_section_name (input_bfd, sec); 3194 } 3195 3196 if (r == bfd_reloc_overflow) 3197 { 3198 if (! ((*info->callbacks->reloc_overflow) 3199 (info, (h ? &h->root : NULL), name, howto->name, 3200 (bfd_vma) 0, input_bfd, input_section, 3201 rel->r_offset))) 3202 return FALSE; 3203 } 3204 else 3205 { 3206 (*_bfd_error_handler) 3207 (_("%B(%A+0x%lx): reloc against `%s': error %d"), 3208 input_bfd, input_section, 3209 (long) rel->r_offset, name, (int) r); 3210 return FALSE; 3211 } 3212 } 3213 } 3214 3215 return TRUE; 3216} 3217 3218/* Finish up dynamic symbol handling. We set the contents of various 3219 dynamic sections here. */ 3220 3221static bfd_boolean 3222elf64_x86_64_finish_dynamic_symbol (bfd *output_bfd, 3223 struct bfd_link_info *info, 3224 struct elf_link_hash_entry *h, 3225 Elf_Internal_Sym *sym) 3226{ 3227 struct elf64_x86_64_link_hash_table *htab; 3228 3229 htab = elf64_x86_64_hash_table (info); 3230 3231 if (h->plt.offset != (bfd_vma) -1) 3232 { 3233 bfd_vma plt_index; 3234 bfd_vma got_offset; 3235 Elf_Internal_Rela rela; 3236 bfd_byte *loc; 3237 3238 /* This symbol has an entry in the procedure linkage table. Set 3239 it up. */ 3240 if (h->dynindx == -1 3241 || htab->splt == NULL 3242 || htab->sgotplt == NULL 3243 || htab->srelplt == NULL) 3244 abort (); 3245 3246 /* Get the index in the procedure linkage table which 3247 corresponds to this symbol. This is the index of this symbol 3248 in all the symbols for which we are making plt entries. The 3249 first entry in the procedure linkage table is reserved. */ 3250 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1; 3251 3252 /* Get the offset into the .got table of the entry that 3253 corresponds to this function. Each .got entry is GOT_ENTRY_SIZE 3254 bytes. The first three are reserved for the dynamic linker. */ 3255 got_offset = (plt_index + 3) * GOT_ENTRY_SIZE; 3256 3257 /* Fill in the entry in the procedure linkage table. */ 3258 memcpy (htab->splt->contents + h->plt.offset, elf64_x86_64_plt_entry, 3259 PLT_ENTRY_SIZE); 3260 3261 /* Insert the relocation positions of the plt section. The magic 3262 numbers at the end of the statements are the positions of the 3263 relocations in the plt section. */ 3264 /* Put offset for jmp *name@GOTPCREL(%rip), since the 3265 instruction uses 6 bytes, subtract this value. */ 3266 bfd_put_32 (output_bfd, 3267 (htab->sgotplt->output_section->vma 3268 + htab->sgotplt->output_offset 3269 + got_offset 3270 - htab->splt->output_section->vma 3271 - htab->splt->output_offset 3272 - h->plt.offset 3273 - 6), 3274 htab->splt->contents + h->plt.offset + 2); 3275 /* Put relocation index. */ 3276 bfd_put_32 (output_bfd, plt_index, 3277 htab->splt->contents + h->plt.offset + 7); 3278 /* Put offset for jmp .PLT0. */ 3279 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE), 3280 htab->splt->contents + h->plt.offset + 12); 3281 3282 /* Fill in the entry in the global offset table, initially this 3283 points to the pushq instruction in the PLT which is at offset 6. */ 3284 bfd_put_64 (output_bfd, (htab->splt->output_section->vma 3285 + htab->splt->output_offset 3286 + h->plt.offset + 6), 3287 htab->sgotplt->contents + got_offset); 3288 3289 /* Fill in the entry in the .rela.plt section. */ 3290 rela.r_offset = (htab->sgotplt->output_section->vma 3291 + htab->sgotplt->output_offset 3292 + got_offset); 3293 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_JUMP_SLOT); 3294 rela.r_addend = 0; 3295 loc = htab->srelplt->contents + plt_index * sizeof (Elf64_External_Rela); 3296 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc); 3297 3298 if (!h->def_regular) 3299 { 3300 /* Mark the symbol as undefined, rather than as defined in 3301 the .plt section. Leave the value if there were any 3302 relocations where pointer equality matters (this is a clue 3303 for the dynamic linker, to make function pointer 3304 comparisons work between an application and shared 3305 library), otherwise set it to zero. If a function is only 3306 called from a binary, there is no need to slow down 3307 shared libraries because of that. */ 3308 sym->st_shndx = SHN_UNDEF; 3309 if (!h->pointer_equality_needed) 3310 sym->st_value = 0; 3311 } 3312 } 3313 3314 if (h->got.offset != (bfd_vma) -1 3315 && ! GOT_TLS_GD_ANY_P (elf64_x86_64_hash_entry (h)->tls_type) 3316 && elf64_x86_64_hash_entry (h)->tls_type != GOT_TLS_IE) 3317 { 3318 Elf_Internal_Rela rela; 3319 bfd_byte *loc; 3320 3321 /* This symbol has an entry in the global offset table. Set it 3322 up. */ 3323 if (htab->sgot == NULL || htab->srelgot == NULL) 3324 abort (); 3325 3326 rela.r_offset = (htab->sgot->output_section->vma 3327 + htab->sgot->output_offset 3328 + (h->got.offset &~ (bfd_vma) 1)); 3329 3330 /* If this is a static link, or it is a -Bsymbolic link and the 3331 symbol is defined locally or was forced to be local because 3332 of a version file, we just want to emit a RELATIVE reloc. 3333 The entry in the global offset table will already have been 3334 initialized in the relocate_section function. */ 3335 if (info->shared 3336 && SYMBOL_REFERENCES_LOCAL (info, h)) 3337 { 3338 BFD_ASSERT((h->got.offset & 1) != 0); 3339 rela.r_info = ELF64_R_INFO (0, R_X86_64_RELATIVE); 3340 rela.r_addend = (h->root.u.def.value 3341 + h->root.u.def.section->output_section->vma 3342 + h->root.u.def.section->output_offset); 3343 } 3344 else 3345 { 3346 BFD_ASSERT((h->got.offset & 1) == 0); 3347 bfd_put_64 (output_bfd, (bfd_vma) 0, 3348 htab->sgot->contents + h->got.offset); 3349 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_GLOB_DAT); 3350 rela.r_addend = 0; 3351 } 3352 3353 loc = htab->srelgot->contents; 3354 loc += htab->srelgot->reloc_count++ * sizeof (Elf64_External_Rela); 3355 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc); 3356 } 3357 3358 if (h->needs_copy) 3359 { 3360 Elf_Internal_Rela rela; 3361 bfd_byte *loc; 3362 3363 /* This symbol needs a copy reloc. Set it up. */ 3364 3365 if (h->dynindx == -1 3366 || (h->root.type != bfd_link_hash_defined 3367 && h->root.type != bfd_link_hash_defweak) 3368 || htab->srelbss == NULL) 3369 abort (); 3370 3371 rela.r_offset = (h->root.u.def.value 3372 + h->root.u.def.section->output_section->vma 3373 + h->root.u.def.section->output_offset); 3374 rela.r_info = ELF64_R_INFO (h->dynindx, R_X86_64_COPY); 3375 rela.r_addend = 0; 3376 loc = htab->srelbss->contents; 3377 loc += htab->srelbss->reloc_count++ * sizeof (Elf64_External_Rela); 3378 bfd_elf64_swap_reloca_out (output_bfd, &rela, loc); 3379 } 3380 3381 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */ 3382 if (strcmp (h->root.root.string, "_DYNAMIC") == 0 3383 || h == htab->elf.hgot) 3384 sym->st_shndx = SHN_ABS; 3385 3386 return TRUE; 3387} 3388 3389/* Used to decide how to sort relocs in an optimal manner for the 3390 dynamic linker, before writing them out. */ 3391 3392static enum elf_reloc_type_class 3393elf64_x86_64_reloc_type_class (const Elf_Internal_Rela *rela) 3394{ 3395 switch ((int) ELF64_R_TYPE (rela->r_info)) 3396 { 3397 case R_X86_64_RELATIVE: 3398 return reloc_class_relative; 3399 case R_X86_64_JUMP_SLOT: 3400 return reloc_class_plt; 3401 case R_X86_64_COPY: 3402 return reloc_class_copy; 3403 default: 3404 return reloc_class_normal; 3405 } 3406} 3407 3408/* Finish up the dynamic sections. */ 3409 3410static bfd_boolean 3411elf64_x86_64_finish_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info) 3412{ 3413 struct elf64_x86_64_link_hash_table *htab; 3414 bfd *dynobj; 3415 asection *sdyn; 3416 3417 htab = elf64_x86_64_hash_table (info); 3418 dynobj = htab->elf.dynobj; 3419 sdyn = bfd_get_section_by_name (dynobj, ".dynamic"); 3420 3421 if (htab->elf.dynamic_sections_created) 3422 { 3423 Elf64_External_Dyn *dyncon, *dynconend; 3424 3425 if (sdyn == NULL || htab->sgot == NULL) 3426 abort (); 3427 3428 dyncon = (Elf64_External_Dyn *) sdyn->contents; 3429 dynconend = (Elf64_External_Dyn *) (sdyn->contents + sdyn->size); 3430 for (; dyncon < dynconend; dyncon++) 3431 { 3432 Elf_Internal_Dyn dyn; 3433 asection *s; 3434 3435 bfd_elf64_swap_dyn_in (dynobj, dyncon, &dyn); 3436 3437 switch (dyn.d_tag) 3438 { 3439 default: 3440 continue; 3441 3442 case DT_PLTGOT: 3443 s = htab->sgotplt; 3444 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset; 3445 break; 3446 3447 case DT_JMPREL: 3448 dyn.d_un.d_ptr = htab->srelplt->output_section->vma; 3449 break; 3450 3451 case DT_PLTRELSZ: 3452 s = htab->srelplt->output_section; 3453 dyn.d_un.d_val = s->size; 3454 break; 3455 3456 case DT_RELASZ: 3457 /* The procedure linkage table relocs (DT_JMPREL) should 3458 not be included in the overall relocs (DT_RELA). 3459 Therefore, we override the DT_RELASZ entry here to 3460 make it not include the JMPREL relocs. Since the 3461 linker script arranges for .rela.plt to follow all 3462 other relocation sections, we don't have to worry 3463 about changing the DT_RELA entry. */ 3464 if (htab->srelplt != NULL) 3465 { 3466 s = htab->srelplt->output_section; 3467 dyn.d_un.d_val -= s->size; 3468 } 3469 break; 3470 3471 case DT_TLSDESC_PLT: 3472 s = htab->splt; 3473 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset 3474 + htab->tlsdesc_plt; 3475 break; 3476 3477 case DT_TLSDESC_GOT: 3478 s = htab->sgot; 3479 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset 3480 + htab->tlsdesc_got; 3481 break; 3482 } 3483 3484 bfd_elf64_swap_dyn_out (output_bfd, &dyn, dyncon); 3485 } 3486 3487 /* Fill in the special first entry in the procedure linkage table. */ 3488 if (htab->splt && htab->splt->size > 0) 3489 { 3490 /* Fill in the first entry in the procedure linkage table. */ 3491 memcpy (htab->splt->contents, elf64_x86_64_plt0_entry, 3492 PLT_ENTRY_SIZE); 3493 /* Add offset for pushq GOT+8(%rip), since the instruction 3494 uses 6 bytes subtract this value. */ 3495 bfd_put_32 (output_bfd, 3496 (htab->sgotplt->output_section->vma 3497 + htab->sgotplt->output_offset 3498 + 8 3499 - htab->splt->output_section->vma 3500 - htab->splt->output_offset 3501 - 6), 3502 htab->splt->contents + 2); 3503 /* Add offset for jmp *GOT+16(%rip). The 12 is the offset to 3504 the end of the instruction. */ 3505 bfd_put_32 (output_bfd, 3506 (htab->sgotplt->output_section->vma 3507 + htab->sgotplt->output_offset 3508 + 16 3509 - htab->splt->output_section->vma 3510 - htab->splt->output_offset 3511 - 12), 3512 htab->splt->contents + 8); 3513 3514 elf_section_data (htab->splt->output_section)->this_hdr.sh_entsize = 3515 PLT_ENTRY_SIZE; 3516 3517 if (htab->tlsdesc_plt) 3518 { 3519 bfd_put_64 (output_bfd, (bfd_vma) 0, 3520 htab->sgot->contents + htab->tlsdesc_got); 3521 3522 memcpy (htab->splt->contents + htab->tlsdesc_plt, 3523 elf64_x86_64_plt0_entry, 3524 PLT_ENTRY_SIZE); 3525 3526 /* Add offset for pushq GOT+8(%rip), since the 3527 instruction uses 6 bytes subtract this value. */ 3528 bfd_put_32 (output_bfd, 3529 (htab->sgotplt->output_section->vma 3530 + htab->sgotplt->output_offset 3531 + 8 3532 - htab->splt->output_section->vma 3533 - htab->splt->output_offset 3534 - htab->tlsdesc_plt 3535 - 6), 3536 htab->splt->contents + htab->tlsdesc_plt + 2); 3537 /* Add offset for jmp *GOT+TDG(%rip), where TGD stands for 3538 htab->tlsdesc_got. The 12 is the offset to the end of 3539 the instruction. */ 3540 bfd_put_32 (output_bfd, 3541 (htab->sgot->output_section->vma 3542 + htab->sgot->output_offset 3543 + htab->tlsdesc_got 3544 - htab->splt->output_section->vma 3545 - htab->splt->output_offset 3546 - htab->tlsdesc_plt 3547 - 12), 3548 htab->splt->contents + htab->tlsdesc_plt + 8); 3549 } 3550 } 3551 } 3552 3553 if (htab->sgotplt) 3554 { 3555 /* Fill in the first three entries in the global offset table. */ 3556 if (htab->sgotplt->size > 0) 3557 { 3558 /* Set the first entry in the global offset table to the address of 3559 the dynamic section. */ 3560 if (sdyn == NULL) 3561 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents); 3562 else 3563 bfd_put_64 (output_bfd, 3564 sdyn->output_section->vma + sdyn->output_offset, 3565 htab->sgotplt->contents); 3566 /* Write GOT[1] and GOT[2], needed for the dynamic linker. */ 3567 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE); 3568 bfd_put_64 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + GOT_ENTRY_SIZE*2); 3569 } 3570 3571 elf_section_data (htab->sgotplt->output_section)->this_hdr.sh_entsize = 3572 GOT_ENTRY_SIZE; 3573 } 3574 3575 if (htab->sgot && htab->sgot->size > 0) 3576 elf_section_data (htab->sgot->output_section)->this_hdr.sh_entsize 3577 = GOT_ENTRY_SIZE; 3578 3579 return TRUE; 3580} 3581 3582/* Return address for Ith PLT stub in section PLT, for relocation REL 3583 or (bfd_vma) -1 if it should not be included. */ 3584 3585static bfd_vma 3586elf64_x86_64_plt_sym_val (bfd_vma i, const asection *plt, 3587 const arelent *rel ATTRIBUTE_UNUSED) 3588{ 3589 return plt->vma + (i + 1) * PLT_ENTRY_SIZE; 3590} 3591 3592/* Handle an x86-64 specific section when reading an object file. This 3593 is called when elfcode.h finds a section with an unknown type. */ 3594 3595static bfd_boolean 3596elf64_x86_64_section_from_shdr (bfd *abfd, 3597 Elf_Internal_Shdr *hdr, 3598 const char *name, 3599 int shindex) 3600{ 3601 if (hdr->sh_type != SHT_X86_64_UNWIND) 3602 return FALSE; 3603 3604 if (! _bfd_elf_make_section_from_shdr (abfd, hdr, name, shindex)) 3605 return FALSE; 3606 3607 return TRUE; 3608} 3609 3610/* Hook called by the linker routine which adds symbols from an object 3611 file. We use it to put SHN_X86_64_LCOMMON items in .lbss, instead 3612 of .bss. */ 3613 3614static bfd_boolean 3615elf64_x86_64_add_symbol_hook (bfd *abfd, 3616 struct bfd_link_info *info ATTRIBUTE_UNUSED, 3617 Elf_Internal_Sym *sym, 3618 const char **namep ATTRIBUTE_UNUSED, 3619 flagword *flagsp ATTRIBUTE_UNUSED, 3620 asection **secp, bfd_vma *valp) 3621{ 3622 asection *lcomm; 3623 3624 switch (sym->st_shndx) 3625 { 3626 case SHN_X86_64_LCOMMON: 3627 lcomm = bfd_get_section_by_name (abfd, "LARGE_COMMON"); 3628 if (lcomm == NULL) 3629 { 3630 lcomm = bfd_make_section_with_flags (abfd, 3631 "LARGE_COMMON", 3632 (SEC_ALLOC 3633 | SEC_IS_COMMON 3634 | SEC_LINKER_CREATED)); 3635 if (lcomm == NULL) 3636 return FALSE; 3637 elf_section_flags (lcomm) |= SHF_X86_64_LARGE; 3638 } 3639 *secp = lcomm; 3640 *valp = sym->st_size; 3641 break; 3642 } 3643 return TRUE; 3644} 3645 3646 3647/* Given a BFD section, try to locate the corresponding ELF section 3648 index. */ 3649 3650static bfd_boolean 3651elf64_x86_64_elf_section_from_bfd_section (bfd *abfd ATTRIBUTE_UNUSED, 3652 asection *sec, int *index) 3653{ 3654 if (sec == &_bfd_elf_large_com_section) 3655 { 3656 *index = SHN_X86_64_LCOMMON; 3657 return TRUE; 3658 } 3659 return FALSE; 3660} 3661 3662/* Process a symbol. */ 3663 3664static void 3665elf64_x86_64_symbol_processing (bfd *abfd ATTRIBUTE_UNUSED, 3666 asymbol *asym) 3667{ 3668 elf_symbol_type *elfsym = (elf_symbol_type *) asym; 3669 3670 switch (elfsym->internal_elf_sym.st_shndx) 3671 { 3672 case SHN_X86_64_LCOMMON: 3673 asym->section = &_bfd_elf_large_com_section; 3674 asym->value = elfsym->internal_elf_sym.st_size; 3675 /* Common symbol doesn't set BSF_GLOBAL. */ 3676 asym->flags &= ~BSF_GLOBAL; 3677 break; 3678 } 3679} 3680 3681static bfd_boolean 3682elf64_x86_64_common_definition (Elf_Internal_Sym *sym) 3683{ 3684 return (sym->st_shndx == SHN_COMMON 3685 || sym->st_shndx == SHN_X86_64_LCOMMON); 3686} 3687 3688static unsigned int 3689elf64_x86_64_common_section_index (asection *sec) 3690{ 3691 if ((elf_section_flags (sec) & SHF_X86_64_LARGE) == 0) 3692 return SHN_COMMON; 3693 else 3694 return SHN_X86_64_LCOMMON; 3695} 3696 3697static asection * 3698elf64_x86_64_common_section (asection *sec) 3699{ 3700 if ((elf_section_flags (sec) & SHF_X86_64_LARGE) == 0) 3701 return bfd_com_section_ptr; 3702 else 3703 return &_bfd_elf_large_com_section; 3704} 3705 3706static bfd_boolean 3707elf64_x86_64_merge_symbol (struct bfd_link_info *info ATTRIBUTE_UNUSED, 3708 struct elf_link_hash_entry **sym_hash ATTRIBUTE_UNUSED, 3709 struct elf_link_hash_entry *h, 3710 Elf_Internal_Sym *sym, 3711 asection **psec, 3712 bfd_vma *pvalue ATTRIBUTE_UNUSED, 3713 unsigned int *pold_alignment ATTRIBUTE_UNUSED, 3714 bfd_boolean *skip ATTRIBUTE_UNUSED, 3715 bfd_boolean *override ATTRIBUTE_UNUSED, 3716 bfd_boolean *type_change_ok ATTRIBUTE_UNUSED, 3717 bfd_boolean *size_change_ok ATTRIBUTE_UNUSED, 3718 bfd_boolean *newdef ATTRIBUTE_UNUSED, 3719 bfd_boolean *newdyn, 3720 bfd_boolean *newdyncommon ATTRIBUTE_UNUSED, 3721 bfd_boolean *newweak ATTRIBUTE_UNUSED, 3722 bfd *abfd ATTRIBUTE_UNUSED, 3723 asection **sec, 3724 bfd_boolean *olddef ATTRIBUTE_UNUSED, 3725 bfd_boolean *olddyn, 3726 bfd_boolean *olddyncommon ATTRIBUTE_UNUSED, 3727 bfd_boolean *oldweak ATTRIBUTE_UNUSED, 3728 bfd *oldbfd, 3729 asection **oldsec) 3730{ 3731 /* A normal common symbol and a large common symbol result in a 3732 normal common symbol. We turn the large common symbol into a 3733 normal one. */ 3734 if (!*olddyn 3735 && h->root.type == bfd_link_hash_common 3736 && !*newdyn 3737 && bfd_is_com_section (*sec) 3738 && *oldsec != *sec) 3739 { 3740 if (sym->st_shndx == SHN_COMMON 3741 && (elf_section_flags (*oldsec) & SHF_X86_64_LARGE) != 0) 3742 { 3743 h->root.u.c.p->section 3744 = bfd_make_section_old_way (oldbfd, "COMMON"); 3745 h->root.u.c.p->section->flags = SEC_ALLOC; 3746 } 3747 else if (sym->st_shndx == SHN_X86_64_LCOMMON 3748 && (elf_section_flags (*oldsec) & SHF_X86_64_LARGE) == 0) 3749 *psec = *sec = bfd_com_section_ptr; 3750 } 3751 3752 return TRUE; 3753} 3754 3755static int 3756elf64_x86_64_additional_program_headers (bfd *abfd, 3757 struct bfd_link_info *info ATTRIBUTE_UNUSED) 3758{ 3759 asection *s; 3760 int count = 0; 3761 3762 /* Check to see if we need a large readonly segment. */ 3763 s = bfd_get_section_by_name (abfd, ".lrodata"); 3764 if (s && (s->flags & SEC_LOAD)) 3765 count++; 3766 3767 /* Check to see if we need a large data segment. Since .lbss sections 3768 is placed right after the .bss section, there should be no need for 3769 a large data segment just because of .lbss. */ 3770 s = bfd_get_section_by_name (abfd, ".ldata"); 3771 if (s && (s->flags & SEC_LOAD)) 3772 count++; 3773 3774 return count; 3775} 3776 3777/* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */ 3778 3779static bfd_boolean 3780elf64_x86_64_hash_symbol (struct elf_link_hash_entry *h) 3781{ 3782 if (h->plt.offset != (bfd_vma) -1 3783 && !h->def_regular 3784 && !h->pointer_equality_needed) 3785 return FALSE; 3786 3787 return _bfd_elf_hash_symbol (h); 3788} 3789 3790static const struct bfd_elf_special_section 3791 elf64_x86_64_special_sections[]= 3792{ 3793 { STRING_COMMA_LEN (".gnu.linkonce.lb"), -2, SHT_NOBITS, SHF_ALLOC + SHF_WRITE + SHF_X86_64_LARGE}, 3794 { STRING_COMMA_LEN (".gnu.linkonce.lr"), -2, SHT_PROGBITS, SHF_ALLOC + SHF_X86_64_LARGE}, 3795 { STRING_COMMA_LEN (".gnu.linkonce.lt"), -2, SHT_PROGBITS, SHF_ALLOC + SHF_EXECINSTR + SHF_X86_64_LARGE}, 3796 { STRING_COMMA_LEN (".lbss"), -2, SHT_NOBITS, SHF_ALLOC + SHF_WRITE + SHF_X86_64_LARGE}, 3797 { STRING_COMMA_LEN (".ldata"), -2, SHT_PROGBITS, SHF_ALLOC + SHF_WRITE + SHF_X86_64_LARGE}, 3798 { STRING_COMMA_LEN (".lrodata"), -2, SHT_PROGBITS, SHF_ALLOC + SHF_X86_64_LARGE}, 3799 { NULL, 0, 0, 0, 0 } 3800}; 3801 3802#define TARGET_LITTLE_SYM bfd_elf64_x86_64_vec 3803#define TARGET_LITTLE_NAME "elf64-x86-64" 3804#define ELF_ARCH bfd_arch_i386 3805#define ELF_MACHINE_CODE EM_X86_64 3806#define ELF_MAXPAGESIZE 0x200000 3807#define ELF_MINPAGESIZE 0x1000 3808#define ELF_COMMONPAGESIZE 0x1000 3809 3810#define elf_backend_can_gc_sections 1 3811#define elf_backend_can_refcount 1 3812#define elf_backend_want_got_plt 1 3813#define elf_backend_plt_readonly 1 3814#define elf_backend_want_plt_sym 0 3815#define elf_backend_got_header_size (GOT_ENTRY_SIZE*3) 3816#define elf_backend_rela_normal 1 3817 3818#define elf_info_to_howto elf64_x86_64_info_to_howto 3819 3820#define bfd_elf64_bfd_link_hash_table_create \ 3821 elf64_x86_64_link_hash_table_create 3822#define bfd_elf64_bfd_reloc_type_lookup elf64_x86_64_reloc_type_lookup 3823#define bfd_elf64_bfd_reloc_name_lookup \ 3824 elf64_x86_64_reloc_name_lookup 3825 3826#define elf_backend_adjust_dynamic_symbol elf64_x86_64_adjust_dynamic_symbol 3827#define elf_backend_check_relocs elf64_x86_64_check_relocs 3828#define elf_backend_copy_indirect_symbol elf64_x86_64_copy_indirect_symbol 3829#define elf_backend_create_dynamic_sections elf64_x86_64_create_dynamic_sections 3830#define elf_backend_finish_dynamic_sections elf64_x86_64_finish_dynamic_sections 3831#define elf_backend_finish_dynamic_symbol elf64_x86_64_finish_dynamic_symbol 3832#define elf_backend_gc_mark_hook elf64_x86_64_gc_mark_hook 3833#define elf_backend_gc_sweep_hook elf64_x86_64_gc_sweep_hook 3834#define elf_backend_grok_prstatus elf64_x86_64_grok_prstatus 3835#define elf_backend_grok_psinfo elf64_x86_64_grok_psinfo 3836#define elf_backend_reloc_type_class elf64_x86_64_reloc_type_class 3837#define elf_backend_relocate_section elf64_x86_64_relocate_section 3838#define elf_backend_size_dynamic_sections elf64_x86_64_size_dynamic_sections 3839#define elf_backend_always_size_sections elf64_x86_64_always_size_sections 3840#define elf_backend_init_index_section _bfd_elf_init_1_index_section 3841#define elf_backend_plt_sym_val elf64_x86_64_plt_sym_val 3842#define elf_backend_object_p elf64_x86_64_elf_object_p 3843#define bfd_elf64_mkobject elf64_x86_64_mkobject 3844 3845#define elf_backend_section_from_shdr \ 3846 elf64_x86_64_section_from_shdr 3847 3848#define elf_backend_section_from_bfd_section \ 3849 elf64_x86_64_elf_section_from_bfd_section 3850#define elf_backend_add_symbol_hook \ 3851 elf64_x86_64_add_symbol_hook 3852#define elf_backend_symbol_processing \ 3853 elf64_x86_64_symbol_processing 3854#define elf_backend_common_section_index \ 3855 elf64_x86_64_common_section_index 3856#define elf_backend_common_section \ 3857 elf64_x86_64_common_section 3858#define elf_backend_common_definition \ 3859 elf64_x86_64_common_definition 3860#define elf_backend_merge_symbol \ 3861 elf64_x86_64_merge_symbol 3862#define elf_backend_special_sections \ 3863 elf64_x86_64_special_sections 3864#define elf_backend_additional_program_headers \ 3865 elf64_x86_64_additional_program_headers 3866#define elf_backend_hash_symbol \ 3867 elf64_x86_64_hash_symbol 3868 3869#include "elf64-target.h" 3870 3871/* FreeBSD support. */ 3872 3873#undef TARGET_LITTLE_SYM 3874#define TARGET_LITTLE_SYM bfd_elf64_x86_64_freebsd_vec 3875#undef TARGET_LITTLE_NAME 3876#define TARGET_LITTLE_NAME "elf64-x86-64-freebsd" 3877 3878#undef ELF_OSABI 3879#define ELF_OSABI ELFOSABI_FREEBSD 3880 3881#undef elf_backend_post_process_headers 3882#define elf_backend_post_process_headers _bfd_elf_set_osabi 3883 3884#undef elf64_bed 3885#define elf64_bed elf64_x86_64_fbsd_bed 3886 3887#include "elf64-target.h" 3888