1 /* Intel 80386/80486-specific support for 32-bit ELF 2 Copyright 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 3 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 4 Free Software Foundation, Inc. 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 "elf-nacl.h" 29 #include "elf-vxworks.h" 30 #include "bfd_stdint.h" 31 #include "objalloc.h" 32 #include "hashtab.h" 33 #include "dwarf2.h" 34 35 /* 386 uses REL relocations instead of RELA. */ 36 #define USE_REL 1 37 38 #include "elf/i386.h" 39 40 static reloc_howto_type elf_howto_table[]= 41 { 42 HOWTO(R_386_NONE, 0, 0, 0, FALSE, 0, complain_overflow_bitfield, 43 bfd_elf_generic_reloc, "R_386_NONE", 44 TRUE, 0x00000000, 0x00000000, FALSE), 45 HOWTO(R_386_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 46 bfd_elf_generic_reloc, "R_386_32", 47 TRUE, 0xffffffff, 0xffffffff, FALSE), 48 HOWTO(R_386_PC32, 0, 2, 32, TRUE, 0, complain_overflow_bitfield, 49 bfd_elf_generic_reloc, "R_386_PC32", 50 TRUE, 0xffffffff, 0xffffffff, TRUE), 51 HOWTO(R_386_GOT32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 52 bfd_elf_generic_reloc, "R_386_GOT32", 53 TRUE, 0xffffffff, 0xffffffff, FALSE), 54 HOWTO(R_386_PLT32, 0, 2, 32, TRUE, 0, complain_overflow_bitfield, 55 bfd_elf_generic_reloc, "R_386_PLT32", 56 TRUE, 0xffffffff, 0xffffffff, TRUE), 57 HOWTO(R_386_COPY, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 58 bfd_elf_generic_reloc, "R_386_COPY", 59 TRUE, 0xffffffff, 0xffffffff, FALSE), 60 HOWTO(R_386_GLOB_DAT, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 61 bfd_elf_generic_reloc, "R_386_GLOB_DAT", 62 TRUE, 0xffffffff, 0xffffffff, FALSE), 63 HOWTO(R_386_JUMP_SLOT, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 64 bfd_elf_generic_reloc, "R_386_JUMP_SLOT", 65 TRUE, 0xffffffff, 0xffffffff, FALSE), 66 HOWTO(R_386_RELATIVE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 67 bfd_elf_generic_reloc, "R_386_RELATIVE", 68 TRUE, 0xffffffff, 0xffffffff, FALSE), 69 HOWTO(R_386_GOTOFF, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 70 bfd_elf_generic_reloc, "R_386_GOTOFF", 71 TRUE, 0xffffffff, 0xffffffff, FALSE), 72 HOWTO(R_386_GOTPC, 0, 2, 32, TRUE, 0, complain_overflow_bitfield, 73 bfd_elf_generic_reloc, "R_386_GOTPC", 74 TRUE, 0xffffffff, 0xffffffff, TRUE), 75 76 /* We have a gap in the reloc numbers here. 77 R_386_standard counts the number up to this point, and 78 R_386_ext_offset is the value to subtract from a reloc type of 79 R_386_16 thru R_386_PC8 to form an index into this table. */ 80 #define R_386_standard (R_386_GOTPC + 1) 81 #define R_386_ext_offset (R_386_TLS_TPOFF - R_386_standard) 82 83 /* These relocs are a GNU extension. */ 84 HOWTO(R_386_TLS_TPOFF, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 85 bfd_elf_generic_reloc, "R_386_TLS_TPOFF", 86 TRUE, 0xffffffff, 0xffffffff, FALSE), 87 HOWTO(R_386_TLS_IE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 88 bfd_elf_generic_reloc, "R_386_TLS_IE", 89 TRUE, 0xffffffff, 0xffffffff, FALSE), 90 HOWTO(R_386_TLS_GOTIE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 91 bfd_elf_generic_reloc, "R_386_TLS_GOTIE", 92 TRUE, 0xffffffff, 0xffffffff, FALSE), 93 HOWTO(R_386_TLS_LE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 94 bfd_elf_generic_reloc, "R_386_TLS_LE", 95 TRUE, 0xffffffff, 0xffffffff, FALSE), 96 HOWTO(R_386_TLS_GD, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 97 bfd_elf_generic_reloc, "R_386_TLS_GD", 98 TRUE, 0xffffffff, 0xffffffff, FALSE), 99 HOWTO(R_386_TLS_LDM, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 100 bfd_elf_generic_reloc, "R_386_TLS_LDM", 101 TRUE, 0xffffffff, 0xffffffff, FALSE), 102 HOWTO(R_386_16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield, 103 bfd_elf_generic_reloc, "R_386_16", 104 TRUE, 0xffff, 0xffff, FALSE), 105 HOWTO(R_386_PC16, 0, 1, 16, TRUE, 0, complain_overflow_bitfield, 106 bfd_elf_generic_reloc, "R_386_PC16", 107 TRUE, 0xffff, 0xffff, TRUE), 108 HOWTO(R_386_8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield, 109 bfd_elf_generic_reloc, "R_386_8", 110 TRUE, 0xff, 0xff, FALSE), 111 HOWTO(R_386_PC8, 0, 0, 8, TRUE, 0, complain_overflow_signed, 112 bfd_elf_generic_reloc, "R_386_PC8", 113 TRUE, 0xff, 0xff, TRUE), 114 115 #define R_386_ext (R_386_PC8 + 1 - R_386_ext_offset) 116 #define R_386_tls_offset (R_386_TLS_LDO_32 - R_386_ext) 117 /* These are common with Solaris TLS implementation. */ 118 HOWTO(R_386_TLS_LDO_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 119 bfd_elf_generic_reloc, "R_386_TLS_LDO_32", 120 TRUE, 0xffffffff, 0xffffffff, FALSE), 121 HOWTO(R_386_TLS_IE_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 122 bfd_elf_generic_reloc, "R_386_TLS_IE_32", 123 TRUE, 0xffffffff, 0xffffffff, FALSE), 124 HOWTO(R_386_TLS_LE_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 125 bfd_elf_generic_reloc, "R_386_TLS_LE_32", 126 TRUE, 0xffffffff, 0xffffffff, FALSE), 127 HOWTO(R_386_TLS_DTPMOD32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 128 bfd_elf_generic_reloc, "R_386_TLS_DTPMOD32", 129 TRUE, 0xffffffff, 0xffffffff, FALSE), 130 HOWTO(R_386_TLS_DTPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 131 bfd_elf_generic_reloc, "R_386_TLS_DTPOFF32", 132 TRUE, 0xffffffff, 0xffffffff, FALSE), 133 HOWTO(R_386_TLS_TPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 134 bfd_elf_generic_reloc, "R_386_TLS_TPOFF32", 135 TRUE, 0xffffffff, 0xffffffff, FALSE), 136 HOWTO(R_386_SIZE32, 0, 2, 32, FALSE, 0, complain_overflow_unsigned, 137 bfd_elf_generic_reloc, "R_386_SIZE32", 138 TRUE, 0xffffffff, 0xffffffff, FALSE), 139 HOWTO(R_386_TLS_GOTDESC, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 140 bfd_elf_generic_reloc, "R_386_TLS_GOTDESC", 141 TRUE, 0xffffffff, 0xffffffff, FALSE), 142 HOWTO(R_386_TLS_DESC_CALL, 0, 0, 0, FALSE, 0, complain_overflow_dont, 143 bfd_elf_generic_reloc, "R_386_TLS_DESC_CALL", 144 FALSE, 0, 0, FALSE), 145 HOWTO(R_386_TLS_DESC, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 146 bfd_elf_generic_reloc, "R_386_TLS_DESC", 147 TRUE, 0xffffffff, 0xffffffff, FALSE), 148 HOWTO(R_386_IRELATIVE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 149 bfd_elf_generic_reloc, "R_386_IRELATIVE", 150 TRUE, 0xffffffff, 0xffffffff, FALSE), 151 152 /* Another gap. */ 153 #define R_386_irelative (R_386_IRELATIVE + 1 - R_386_tls_offset) 154 #define R_386_vt_offset (R_386_GNU_VTINHERIT - R_386_irelative) 155 156 /* GNU extension to record C++ vtable hierarchy. */ 157 HOWTO (R_386_GNU_VTINHERIT, /* type */ 158 0, /* rightshift */ 159 2, /* size (0 = byte, 1 = short, 2 = long) */ 160 0, /* bitsize */ 161 FALSE, /* pc_relative */ 162 0, /* bitpos */ 163 complain_overflow_dont, /* complain_on_overflow */ 164 NULL, /* special_function */ 165 "R_386_GNU_VTINHERIT", /* name */ 166 FALSE, /* partial_inplace */ 167 0, /* src_mask */ 168 0, /* dst_mask */ 169 FALSE), /* pcrel_offset */ 170 171 /* GNU extension to record C++ vtable member usage. */ 172 HOWTO (R_386_GNU_VTENTRY, /* type */ 173 0, /* rightshift */ 174 2, /* size (0 = byte, 1 = short, 2 = long) */ 175 0, /* bitsize */ 176 FALSE, /* pc_relative */ 177 0, /* bitpos */ 178 complain_overflow_dont, /* complain_on_overflow */ 179 _bfd_elf_rel_vtable_reloc_fn, /* special_function */ 180 "R_386_GNU_VTENTRY", /* name */ 181 FALSE, /* partial_inplace */ 182 0, /* src_mask */ 183 0, /* dst_mask */ 184 FALSE) /* pcrel_offset */ 185 186 #define R_386_vt (R_386_GNU_VTENTRY + 1 - R_386_vt_offset) 187 188 }; 189 190 #ifdef DEBUG_GEN_RELOC 191 #define TRACE(str) \ 192 fprintf (stderr, "i386 bfd reloc lookup %d (%s)\n", code, str) 193 #else 194 #define TRACE(str) 195 #endif 196 197 static reloc_howto_type * 198 elf_i386_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED, 199 bfd_reloc_code_real_type code) 200 { 201 switch (code) 202 { 203 case BFD_RELOC_NONE: 204 TRACE ("BFD_RELOC_NONE"); 205 return &elf_howto_table[R_386_NONE]; 206 207 case BFD_RELOC_32: 208 TRACE ("BFD_RELOC_32"); 209 return &elf_howto_table[R_386_32]; 210 211 case BFD_RELOC_CTOR: 212 TRACE ("BFD_RELOC_CTOR"); 213 return &elf_howto_table[R_386_32]; 214 215 case BFD_RELOC_32_PCREL: 216 TRACE ("BFD_RELOC_PC32"); 217 return &elf_howto_table[R_386_PC32]; 218 219 case BFD_RELOC_386_GOT32: 220 TRACE ("BFD_RELOC_386_GOT32"); 221 return &elf_howto_table[R_386_GOT32]; 222 223 case BFD_RELOC_386_PLT32: 224 TRACE ("BFD_RELOC_386_PLT32"); 225 return &elf_howto_table[R_386_PLT32]; 226 227 case BFD_RELOC_386_COPY: 228 TRACE ("BFD_RELOC_386_COPY"); 229 return &elf_howto_table[R_386_COPY]; 230 231 case BFD_RELOC_386_GLOB_DAT: 232 TRACE ("BFD_RELOC_386_GLOB_DAT"); 233 return &elf_howto_table[R_386_GLOB_DAT]; 234 235 case BFD_RELOC_386_JUMP_SLOT: 236 TRACE ("BFD_RELOC_386_JUMP_SLOT"); 237 return &elf_howto_table[R_386_JUMP_SLOT]; 238 239 case BFD_RELOC_386_RELATIVE: 240 TRACE ("BFD_RELOC_386_RELATIVE"); 241 return &elf_howto_table[R_386_RELATIVE]; 242 243 case BFD_RELOC_386_GOTOFF: 244 TRACE ("BFD_RELOC_386_GOTOFF"); 245 return &elf_howto_table[R_386_GOTOFF]; 246 247 case BFD_RELOC_386_GOTPC: 248 TRACE ("BFD_RELOC_386_GOTPC"); 249 return &elf_howto_table[R_386_GOTPC]; 250 251 /* These relocs are a GNU extension. */ 252 case BFD_RELOC_386_TLS_TPOFF: 253 TRACE ("BFD_RELOC_386_TLS_TPOFF"); 254 return &elf_howto_table[R_386_TLS_TPOFF - R_386_ext_offset]; 255 256 case BFD_RELOC_386_TLS_IE: 257 TRACE ("BFD_RELOC_386_TLS_IE"); 258 return &elf_howto_table[R_386_TLS_IE - R_386_ext_offset]; 259 260 case BFD_RELOC_386_TLS_GOTIE: 261 TRACE ("BFD_RELOC_386_TLS_GOTIE"); 262 return &elf_howto_table[R_386_TLS_GOTIE - R_386_ext_offset]; 263 264 case BFD_RELOC_386_TLS_LE: 265 TRACE ("BFD_RELOC_386_TLS_LE"); 266 return &elf_howto_table[R_386_TLS_LE - R_386_ext_offset]; 267 268 case BFD_RELOC_386_TLS_GD: 269 TRACE ("BFD_RELOC_386_TLS_GD"); 270 return &elf_howto_table[R_386_TLS_GD - R_386_ext_offset]; 271 272 case BFD_RELOC_386_TLS_LDM: 273 TRACE ("BFD_RELOC_386_TLS_LDM"); 274 return &elf_howto_table[R_386_TLS_LDM - R_386_ext_offset]; 275 276 case BFD_RELOC_16: 277 TRACE ("BFD_RELOC_16"); 278 return &elf_howto_table[R_386_16 - R_386_ext_offset]; 279 280 case BFD_RELOC_16_PCREL: 281 TRACE ("BFD_RELOC_16_PCREL"); 282 return &elf_howto_table[R_386_PC16 - R_386_ext_offset]; 283 284 case BFD_RELOC_8: 285 TRACE ("BFD_RELOC_8"); 286 return &elf_howto_table[R_386_8 - R_386_ext_offset]; 287 288 case BFD_RELOC_8_PCREL: 289 TRACE ("BFD_RELOC_8_PCREL"); 290 return &elf_howto_table[R_386_PC8 - R_386_ext_offset]; 291 292 /* Common with Sun TLS implementation. */ 293 case BFD_RELOC_386_TLS_LDO_32: 294 TRACE ("BFD_RELOC_386_TLS_LDO_32"); 295 return &elf_howto_table[R_386_TLS_LDO_32 - R_386_tls_offset]; 296 297 case BFD_RELOC_386_TLS_IE_32: 298 TRACE ("BFD_RELOC_386_TLS_IE_32"); 299 return &elf_howto_table[R_386_TLS_IE_32 - R_386_tls_offset]; 300 301 case BFD_RELOC_386_TLS_LE_32: 302 TRACE ("BFD_RELOC_386_TLS_LE_32"); 303 return &elf_howto_table[R_386_TLS_LE_32 - R_386_tls_offset]; 304 305 case BFD_RELOC_386_TLS_DTPMOD32: 306 TRACE ("BFD_RELOC_386_TLS_DTPMOD32"); 307 return &elf_howto_table[R_386_TLS_DTPMOD32 - R_386_tls_offset]; 308 309 case BFD_RELOC_386_TLS_DTPOFF32: 310 TRACE ("BFD_RELOC_386_TLS_DTPOFF32"); 311 return &elf_howto_table[R_386_TLS_DTPOFF32 - R_386_tls_offset]; 312 313 case BFD_RELOC_386_TLS_TPOFF32: 314 TRACE ("BFD_RELOC_386_TLS_TPOFF32"); 315 return &elf_howto_table[R_386_TLS_TPOFF32 - R_386_tls_offset]; 316 317 case BFD_RELOC_SIZE32: 318 TRACE ("BFD_RELOC_SIZE32"); 319 return &elf_howto_table[R_386_SIZE32 - R_386_tls_offset]; 320 321 case BFD_RELOC_386_TLS_GOTDESC: 322 TRACE ("BFD_RELOC_386_TLS_GOTDESC"); 323 return &elf_howto_table[R_386_TLS_GOTDESC - R_386_tls_offset]; 324 325 case BFD_RELOC_386_TLS_DESC_CALL: 326 TRACE ("BFD_RELOC_386_TLS_DESC_CALL"); 327 return &elf_howto_table[R_386_TLS_DESC_CALL - R_386_tls_offset]; 328 329 case BFD_RELOC_386_TLS_DESC: 330 TRACE ("BFD_RELOC_386_TLS_DESC"); 331 return &elf_howto_table[R_386_TLS_DESC - R_386_tls_offset]; 332 333 case BFD_RELOC_386_IRELATIVE: 334 TRACE ("BFD_RELOC_386_IRELATIVE"); 335 return &elf_howto_table[R_386_IRELATIVE - R_386_tls_offset]; 336 337 case BFD_RELOC_VTABLE_INHERIT: 338 TRACE ("BFD_RELOC_VTABLE_INHERIT"); 339 return &elf_howto_table[R_386_GNU_VTINHERIT - R_386_vt_offset]; 340 341 case BFD_RELOC_VTABLE_ENTRY: 342 TRACE ("BFD_RELOC_VTABLE_ENTRY"); 343 return &elf_howto_table[R_386_GNU_VTENTRY - R_386_vt_offset]; 344 345 default: 346 break; 347 } 348 349 TRACE ("Unknown"); 350 return 0; 351 } 352 353 static reloc_howto_type * 354 elf_i386_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED, 355 const char *r_name) 356 { 357 unsigned int i; 358 359 for (i = 0; i < sizeof (elf_howto_table) / sizeof (elf_howto_table[0]); i++) 360 if (elf_howto_table[i].name != NULL 361 && strcasecmp (elf_howto_table[i].name, r_name) == 0) 362 return &elf_howto_table[i]; 363 364 return NULL; 365 } 366 367 static reloc_howto_type * 368 elf_i386_rtype_to_howto (bfd *abfd, unsigned r_type) 369 { 370 unsigned int indx; 371 372 if ((indx = r_type) >= R_386_standard 373 && ((indx = r_type - R_386_ext_offset) - R_386_standard 374 >= R_386_ext - R_386_standard) 375 && ((indx = r_type - R_386_tls_offset) - R_386_ext 376 >= R_386_irelative - R_386_ext) 377 && ((indx = r_type - R_386_vt_offset) - R_386_irelative 378 >= R_386_vt - R_386_irelative)) 379 { 380 (*_bfd_error_handler) (_("%B: invalid relocation type %d"), 381 abfd, (int) r_type); 382 indx = R_386_NONE; 383 } 384 BFD_ASSERT (elf_howto_table [indx].type == r_type); 385 return &elf_howto_table[indx]; 386 } 387 388 static void 389 elf_i386_info_to_howto_rel (bfd *abfd ATTRIBUTE_UNUSED, 390 arelent *cache_ptr, 391 Elf_Internal_Rela *dst) 392 { 393 unsigned int r_type = ELF32_R_TYPE (dst->r_info); 394 cache_ptr->howto = elf_i386_rtype_to_howto (abfd, r_type); 395 } 396 397 /* Return whether a symbol name implies a local label. The UnixWare 398 2.1 cc generates temporary symbols that start with .X, so we 399 recognize them here. FIXME: do other SVR4 compilers also use .X?. 400 If so, we should move the .X recognition into 401 _bfd_elf_is_local_label_name. */ 402 403 static bfd_boolean 404 elf_i386_is_local_label_name (bfd *abfd, const char *name) 405 { 406 if (name[0] == '.' && name[1] == 'X') 407 return TRUE; 408 409 return _bfd_elf_is_local_label_name (abfd, name); 410 } 411 412 /* Support for core dump NOTE sections. */ 413 414 static bfd_boolean 415 elf_i386_grok_prstatus (bfd *abfd, Elf_Internal_Note *note) 416 { 417 int offset; 418 size_t size; 419 420 if (note->namesz == 8 && strcmp (note->namedata, "FreeBSD") == 0) 421 { 422 int pr_version = bfd_get_32 (abfd, note->descdata); 423 424 if (pr_version != 1) 425 return FALSE; 426 427 /* pr_cursig */ 428 elf_tdata (abfd)->core->signal = bfd_get_32 (abfd, note->descdata + 20); 429 430 /* pr_pid */ 431 elf_tdata (abfd)->core->lwpid = bfd_get_32 (abfd, note->descdata + 24); 432 433 /* pr_reg */ 434 offset = 28; 435 size = bfd_get_32 (abfd, note->descdata + 8); 436 } 437 else 438 { 439 switch (note->descsz) 440 { 441 default: 442 return FALSE; 443 444 case 144: /* Linux/i386 */ 445 /* pr_cursig */ 446 elf_tdata (abfd)->core->signal = bfd_get_16 (abfd, note->descdata + 12); 447 448 /* pr_pid */ 449 elf_tdata (abfd)->core->lwpid = bfd_get_32 (abfd, note->descdata + 24); 450 451 /* pr_reg */ 452 offset = 72; 453 size = 68; 454 455 break; 456 } 457 } 458 459 /* Make a ".reg/999" section. */ 460 return _bfd_elfcore_make_pseudosection (abfd, ".reg", 461 size, note->descpos + offset); 462 } 463 464 static bfd_boolean 465 elf_i386_grok_psinfo (bfd *abfd, Elf_Internal_Note *note) 466 { 467 if (note->namesz == 8 && strcmp (note->namedata, "FreeBSD") == 0) 468 { 469 int pr_version = bfd_get_32 (abfd, note->descdata); 470 471 if (pr_version != 1) 472 return FALSE; 473 474 elf_tdata (abfd)->core->program 475 = _bfd_elfcore_strndup (abfd, note->descdata + 8, 17); 476 elf_tdata (abfd)->core->command 477 = _bfd_elfcore_strndup (abfd, note->descdata + 25, 81); 478 } 479 else 480 { 481 switch (note->descsz) 482 { 483 default: 484 return FALSE; 485 486 case 124: /* Linux/i386 elf_prpsinfo. */ 487 elf_tdata (abfd)->core->pid 488 = bfd_get_32 (abfd, note->descdata + 12); 489 elf_tdata (abfd)->core->program 490 = _bfd_elfcore_strndup (abfd, note->descdata + 28, 16); 491 elf_tdata (abfd)->core->command 492 = _bfd_elfcore_strndup (abfd, note->descdata + 44, 80); 493 } 494 } 495 496 /* Note that for some reason, a spurious space is tacked 497 onto the end of the args in some (at least one anyway) 498 implementations, so strip it off if it exists. */ 499 { 500 char *command = elf_tdata (abfd)->core->command; 501 int n = strlen (command); 502 503 if (0 < n && command[n - 1] == ' ') 504 command[n - 1] = '\0'; 505 } 506 507 return TRUE; 508 } 509 510 /* Functions for the i386 ELF linker. 511 512 In order to gain some understanding of code in this file without 513 knowing all the intricate details of the linker, note the 514 following: 515 516 Functions named elf_i386_* are called by external routines, other 517 functions are only called locally. elf_i386_* functions appear 518 in this file more or less in the order in which they are called 519 from external routines. eg. elf_i386_check_relocs is called 520 early in the link process, elf_i386_finish_dynamic_sections is 521 one of the last functions. */ 522 523 524 /* The name of the dynamic interpreter. This is put in the .interp 525 section. */ 526 527 #define ELF_DYNAMIC_INTERPRETER "/usr/lib/libc.so.1" 528 529 /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid 530 copying dynamic variables from a shared lib into an app's dynbss 531 section, and instead use a dynamic relocation to point into the 532 shared lib. */ 533 #define ELIMINATE_COPY_RELOCS 1 534 535 /* The size in bytes of an entry in the procedure linkage table. */ 536 537 #define PLT_ENTRY_SIZE 16 538 539 /* The first entry in an absolute procedure linkage table looks like 540 this. See the SVR4 ABI i386 supplement to see how this works. 541 Will be padded to PLT_ENTRY_SIZE with htab->plt0_pad_byte. */ 542 543 static const bfd_byte elf_i386_plt0_entry[12] = 544 { 545 0xff, 0x35, /* pushl contents of address */ 546 0, 0, 0, 0, /* replaced with address of .got + 4. */ 547 0xff, 0x25, /* jmp indirect */ 548 0, 0, 0, 0 /* replaced with address of .got + 8. */ 549 }; 550 551 /* Subsequent entries in an absolute procedure linkage table look like 552 this. */ 553 554 static const bfd_byte elf_i386_plt_entry[PLT_ENTRY_SIZE] = 555 { 556 0xff, 0x25, /* jmp indirect */ 557 0, 0, 0, 0, /* replaced with address of this symbol in .got. */ 558 0x68, /* pushl immediate */ 559 0, 0, 0, 0, /* replaced with offset into relocation table. */ 560 0xe9, /* jmp relative */ 561 0, 0, 0, 0 /* replaced with offset to start of .plt. */ 562 }; 563 564 /* The first entry in a PIC procedure linkage table look like this. 565 Will be padded to PLT_ENTRY_SIZE with htab->plt0_pad_byte. */ 566 567 static const bfd_byte elf_i386_pic_plt0_entry[12] = 568 { 569 0xff, 0xb3, 4, 0, 0, 0, /* pushl 4(%ebx) */ 570 0xff, 0xa3, 8, 0, 0, 0 /* jmp *8(%ebx) */ 571 }; 572 573 /* Subsequent entries in a PIC procedure linkage table look like this. */ 574 575 static const bfd_byte elf_i386_pic_plt_entry[PLT_ENTRY_SIZE] = 576 { 577 0xff, 0xa3, /* jmp *offset(%ebx) */ 578 0, 0, 0, 0, /* replaced with offset of this symbol in .got. */ 579 0x68, /* pushl immediate */ 580 0, 0, 0, 0, /* replaced with offset into relocation table. */ 581 0xe9, /* jmp relative */ 582 0, 0, 0, 0 /* replaced with offset to start of .plt. */ 583 }; 584 585 /* .eh_frame covering the .plt section. */ 586 587 static const bfd_byte elf_i386_eh_frame_plt[] = 588 { 589 #define PLT_CIE_LENGTH 20 590 #define PLT_FDE_LENGTH 36 591 #define PLT_FDE_START_OFFSET 4 + PLT_CIE_LENGTH + 8 592 #define PLT_FDE_LEN_OFFSET 4 + PLT_CIE_LENGTH + 12 593 PLT_CIE_LENGTH, 0, 0, 0, /* CIE length */ 594 0, 0, 0, 0, /* CIE ID */ 595 1, /* CIE version */ 596 'z', 'R', 0, /* Augmentation string */ 597 1, /* Code alignment factor */ 598 0x7c, /* Data alignment factor */ 599 8, /* Return address column */ 600 1, /* Augmentation size */ 601 DW_EH_PE_pcrel | DW_EH_PE_sdata4, /* FDE encoding */ 602 DW_CFA_def_cfa, 4, 4, /* DW_CFA_def_cfa: r4 (esp) ofs 4 */ 603 DW_CFA_offset + 8, 1, /* DW_CFA_offset: r8 (eip) at cfa-4 */ 604 DW_CFA_nop, DW_CFA_nop, 605 606 PLT_FDE_LENGTH, 0, 0, 0, /* FDE length */ 607 PLT_CIE_LENGTH + 8, 0, 0, 0, /* CIE pointer */ 608 0, 0, 0, 0, /* R_386_PC32 .plt goes here */ 609 0, 0, 0, 0, /* .plt size goes here */ 610 0, /* Augmentation size */ 611 DW_CFA_def_cfa_offset, 8, /* DW_CFA_def_cfa_offset: 8 */ 612 DW_CFA_advance_loc + 6, /* DW_CFA_advance_loc: 6 to __PLT__+6 */ 613 DW_CFA_def_cfa_offset, 12, /* DW_CFA_def_cfa_offset: 12 */ 614 DW_CFA_advance_loc + 10, /* DW_CFA_advance_loc: 10 to __PLT__+16 */ 615 DW_CFA_def_cfa_expression, /* DW_CFA_def_cfa_expression */ 616 11, /* Block length */ 617 DW_OP_breg4, 4, /* DW_OP_breg4 (esp): 4 */ 618 DW_OP_breg8, 0, /* DW_OP_breg8 (eip): 0 */ 619 DW_OP_lit15, DW_OP_and, DW_OP_lit11, DW_OP_ge, 620 DW_OP_lit2, DW_OP_shl, DW_OP_plus, 621 DW_CFA_nop, DW_CFA_nop, DW_CFA_nop, DW_CFA_nop 622 }; 623 624 struct elf_i386_plt_layout 625 { 626 /* The first entry in an absolute procedure linkage table looks like this. */ 627 const bfd_byte *plt0_entry; 628 unsigned int plt0_entry_size; 629 630 /* Offsets into plt0_entry that are to be replaced with GOT[1] and GOT[2]. */ 631 unsigned int plt0_got1_offset; 632 unsigned int plt0_got2_offset; 633 634 /* Later entries in an absolute procedure linkage table look like this. */ 635 const bfd_byte *plt_entry; 636 unsigned int plt_entry_size; 637 638 /* Offsets into plt_entry that are to be replaced with... */ 639 unsigned int plt_got_offset; /* ... address of this symbol in .got. */ 640 unsigned int plt_reloc_offset; /* ... offset into relocation table. */ 641 unsigned int plt_plt_offset; /* ... offset to start of .plt. */ 642 643 /* Offset into plt_entry where the initial value of the GOT entry points. */ 644 unsigned int plt_lazy_offset; 645 646 /* The first entry in a PIC procedure linkage table looks like this. */ 647 const bfd_byte *pic_plt0_entry; 648 649 /* Subsequent entries in a PIC procedure linkage table look like this. */ 650 const bfd_byte *pic_plt_entry; 651 652 /* .eh_frame covering the .plt section. */ 653 const bfd_byte *eh_frame_plt; 654 unsigned int eh_frame_plt_size; 655 }; 656 657 #define GET_PLT_ENTRY_SIZE(abfd) \ 658 get_elf_i386_backend_data (abfd)->plt->plt_entry_size 659 660 /* These are the standard parameters. */ 661 static const struct elf_i386_plt_layout elf_i386_plt = 662 { 663 elf_i386_plt0_entry, /* plt0_entry */ 664 sizeof (elf_i386_plt0_entry), /* plt0_entry_size */ 665 2, /* plt0_got1_offset */ 666 8, /* plt0_got2_offset */ 667 elf_i386_plt_entry, /* plt_entry */ 668 PLT_ENTRY_SIZE, /* plt_entry_size */ 669 2, /* plt_got_offset */ 670 7, /* plt_reloc_offset */ 671 12, /* plt_plt_offset */ 672 6, /* plt_lazy_offset */ 673 elf_i386_pic_plt0_entry, /* pic_plt0_entry */ 674 elf_i386_pic_plt_entry, /* pic_plt_entry */ 675 elf_i386_eh_frame_plt, /* eh_frame_plt */ 676 sizeof (elf_i386_eh_frame_plt), /* eh_frame_plt_size */ 677 }; 678 679 680 /* On VxWorks, the .rel.plt.unloaded section has absolute relocations 681 for the PLTResolve stub and then for each PLT entry. */ 682 #define PLTRESOLVE_RELOCS_SHLIB 0 683 #define PLTRESOLVE_RELOCS 2 684 #define PLT_NON_JUMP_SLOT_RELOCS 2 685 686 /* Architecture-specific backend data for i386. */ 687 688 struct elf_i386_backend_data 689 { 690 /* Parameters describing PLT generation. */ 691 const struct elf_i386_plt_layout *plt; 692 693 /* Value used to fill the unused bytes of the first PLT entry. */ 694 bfd_byte plt0_pad_byte; 695 696 /* True if the target system is VxWorks. */ 697 int is_vxworks; 698 }; 699 700 #define get_elf_i386_backend_data(abfd) \ 701 ((const struct elf_i386_backend_data *) \ 702 get_elf_backend_data (abfd)->arch_data) 703 704 /* These are the standard parameters. */ 705 static const struct elf_i386_backend_data elf_i386_arch_bed = 706 { 707 &elf_i386_plt, /* plt */ 708 0, /* plt0_pad_byte */ 709 0, /* is_vxworks */ 710 }; 711 712 #define elf_backend_arch_data &elf_i386_arch_bed 713 714 /* i386 ELF linker hash entry. */ 715 716 struct elf_i386_link_hash_entry 717 { 718 struct elf_link_hash_entry elf; 719 720 /* Track dynamic relocs copied for this symbol. */ 721 struct elf_dyn_relocs *dyn_relocs; 722 723 #define GOT_UNKNOWN 0 724 #define GOT_NORMAL 1 725 #define GOT_TLS_GD 2 726 #define GOT_TLS_IE 4 727 #define GOT_TLS_IE_POS 5 728 #define GOT_TLS_IE_NEG 6 729 #define GOT_TLS_IE_BOTH 7 730 #define GOT_TLS_GDESC 8 731 #define GOT_TLS_GD_BOTH_P(type) \ 732 ((type) == (GOT_TLS_GD | GOT_TLS_GDESC)) 733 #define GOT_TLS_GD_P(type) \ 734 ((type) == GOT_TLS_GD || GOT_TLS_GD_BOTH_P (type)) 735 #define GOT_TLS_GDESC_P(type) \ 736 ((type) == GOT_TLS_GDESC || GOT_TLS_GD_BOTH_P (type)) 737 #define GOT_TLS_GD_ANY_P(type) \ 738 (GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type)) 739 unsigned char tls_type; 740 741 /* Offset of the GOTPLT entry reserved for the TLS descriptor, 742 starting at the end of the jump table. */ 743 bfd_vma tlsdesc_got; 744 }; 745 746 #define elf_i386_hash_entry(ent) ((struct elf_i386_link_hash_entry *)(ent)) 747 748 struct elf_i386_obj_tdata 749 { 750 struct elf_obj_tdata root; 751 752 /* tls_type for each local got entry. */ 753 char *local_got_tls_type; 754 755 /* GOTPLT entries for TLS descriptors. */ 756 bfd_vma *local_tlsdesc_gotent; 757 }; 758 759 #define elf_i386_tdata(abfd) \ 760 ((struct elf_i386_obj_tdata *) (abfd)->tdata.any) 761 762 #define elf_i386_local_got_tls_type(abfd) \ 763 (elf_i386_tdata (abfd)->local_got_tls_type) 764 765 #define elf_i386_local_tlsdesc_gotent(abfd) \ 766 (elf_i386_tdata (abfd)->local_tlsdesc_gotent) 767 768 #define is_i386_elf(bfd) \ 769 (bfd_get_flavour (bfd) == bfd_target_elf_flavour \ 770 && elf_tdata (bfd) != NULL \ 771 && elf_object_id (bfd) == I386_ELF_DATA) 772 773 static bfd_boolean 774 elf_i386_mkobject (bfd *abfd) 775 { 776 return bfd_elf_allocate_object (abfd, sizeof (struct elf_i386_obj_tdata), 777 I386_ELF_DATA); 778 } 779 780 /* i386 ELF linker hash table. */ 781 782 struct elf_i386_link_hash_table 783 { 784 struct elf_link_hash_table elf; 785 786 /* Short-cuts to get to dynamic linker sections. */ 787 asection *sdynbss; 788 asection *srelbss; 789 asection *plt_eh_frame; 790 791 union 792 { 793 bfd_signed_vma refcount; 794 bfd_vma offset; 795 } tls_ldm_got; 796 797 /* The amount of space used by the reserved portion of the sgotplt 798 section, plus whatever space is used by the jump slots. */ 799 bfd_vma sgotplt_jump_table_size; 800 801 /* Small local sym cache. */ 802 struct sym_cache sym_cache; 803 804 /* _TLS_MODULE_BASE_ symbol. */ 805 struct bfd_link_hash_entry *tls_module_base; 806 807 /* Used by local STT_GNU_IFUNC symbols. */ 808 htab_t loc_hash_table; 809 void * loc_hash_memory; 810 811 /* The (unloaded but important) .rel.plt.unloaded section on VxWorks. */ 812 asection *srelplt2; 813 814 /* The index of the next unused R_386_TLS_DESC slot in .rel.plt. */ 815 bfd_vma next_tls_desc_index; 816 817 /* The index of the next unused R_386_JUMP_SLOT slot in .rel.plt. */ 818 bfd_vma next_jump_slot_index; 819 820 /* The index of the next unused R_386_IRELATIVE slot in .rel.plt. */ 821 bfd_vma next_irelative_index; 822 }; 823 824 /* Get the i386 ELF linker hash table from a link_info structure. */ 825 826 #define elf_i386_hash_table(p) \ 827 (elf_hash_table_id ((struct elf_link_hash_table *) ((p)->hash)) \ 828 == I386_ELF_DATA ? ((struct elf_i386_link_hash_table *) ((p)->hash)) : NULL) 829 830 #define elf_i386_compute_jump_table_size(htab) \ 831 ((htab)->next_tls_desc_index * 4) 832 833 /* Create an entry in an i386 ELF linker hash table. */ 834 835 static struct bfd_hash_entry * 836 elf_i386_link_hash_newfunc (struct bfd_hash_entry *entry, 837 struct bfd_hash_table *table, 838 const char *string) 839 { 840 /* Allocate the structure if it has not already been allocated by a 841 subclass. */ 842 if (entry == NULL) 843 { 844 entry = (struct bfd_hash_entry *) 845 bfd_hash_allocate (table, sizeof (struct elf_i386_link_hash_entry)); 846 if (entry == NULL) 847 return entry; 848 } 849 850 /* Call the allocation method of the superclass. */ 851 entry = _bfd_elf_link_hash_newfunc (entry, table, string); 852 if (entry != NULL) 853 { 854 struct elf_i386_link_hash_entry *eh; 855 856 eh = (struct elf_i386_link_hash_entry *) entry; 857 eh->dyn_relocs = NULL; 858 eh->tls_type = GOT_UNKNOWN; 859 eh->tlsdesc_got = (bfd_vma) -1; 860 } 861 862 return entry; 863 } 864 865 /* Compute a hash of a local hash entry. We use elf_link_hash_entry 866 for local symbol so that we can handle local STT_GNU_IFUNC symbols 867 as global symbol. We reuse indx and dynstr_index for local symbol 868 hash since they aren't used by global symbols in this backend. */ 869 870 static hashval_t 871 elf_i386_local_htab_hash (const void *ptr) 872 { 873 struct elf_link_hash_entry *h 874 = (struct elf_link_hash_entry *) ptr; 875 return ELF_LOCAL_SYMBOL_HASH (h->indx, h->dynstr_index); 876 } 877 878 /* Compare local hash entries. */ 879 880 static int 881 elf_i386_local_htab_eq (const void *ptr1, const void *ptr2) 882 { 883 struct elf_link_hash_entry *h1 884 = (struct elf_link_hash_entry *) ptr1; 885 struct elf_link_hash_entry *h2 886 = (struct elf_link_hash_entry *) ptr2; 887 888 return h1->indx == h2->indx && h1->dynstr_index == h2->dynstr_index; 889 } 890 891 /* Find and/or create a hash entry for local symbol. */ 892 893 static struct elf_link_hash_entry * 894 elf_i386_get_local_sym_hash (struct elf_i386_link_hash_table *htab, 895 bfd *abfd, const Elf_Internal_Rela *rel, 896 bfd_boolean create) 897 { 898 struct elf_i386_link_hash_entry e, *ret; 899 asection *sec = abfd->sections; 900 hashval_t h = ELF_LOCAL_SYMBOL_HASH (sec->id, 901 ELF32_R_SYM (rel->r_info)); 902 void **slot; 903 904 e.elf.indx = sec->id; 905 e.elf.dynstr_index = ELF32_R_SYM (rel->r_info); 906 slot = htab_find_slot_with_hash (htab->loc_hash_table, &e, h, 907 create ? INSERT : NO_INSERT); 908 909 if (!slot) 910 return NULL; 911 912 if (*slot) 913 { 914 ret = (struct elf_i386_link_hash_entry *) *slot; 915 return &ret->elf; 916 } 917 918 ret = (struct elf_i386_link_hash_entry *) 919 objalloc_alloc ((struct objalloc *) htab->loc_hash_memory, 920 sizeof (struct elf_i386_link_hash_entry)); 921 if (ret) 922 { 923 memset (ret, 0, sizeof (*ret)); 924 ret->elf.indx = sec->id; 925 ret->elf.dynstr_index = ELF32_R_SYM (rel->r_info); 926 ret->elf.dynindx = -1; 927 *slot = ret; 928 } 929 return &ret->elf; 930 } 931 932 /* Create an i386 ELF linker hash table. */ 933 934 static struct bfd_link_hash_table * 935 elf_i386_link_hash_table_create (bfd *abfd) 936 { 937 struct elf_i386_link_hash_table *ret; 938 bfd_size_type amt = sizeof (struct elf_i386_link_hash_table); 939 940 ret = (struct elf_i386_link_hash_table *) bfd_zmalloc (amt); 941 if (ret == NULL) 942 return NULL; 943 944 if (!_bfd_elf_link_hash_table_init (&ret->elf, abfd, 945 elf_i386_link_hash_newfunc, 946 sizeof (struct elf_i386_link_hash_entry), 947 I386_ELF_DATA)) 948 { 949 free (ret); 950 return NULL; 951 } 952 953 ret->loc_hash_table = htab_try_create (1024, 954 elf_i386_local_htab_hash, 955 elf_i386_local_htab_eq, 956 NULL); 957 ret->loc_hash_memory = objalloc_create (); 958 if (!ret->loc_hash_table || !ret->loc_hash_memory) 959 { 960 free (ret); 961 return NULL; 962 } 963 964 return &ret->elf.root; 965 } 966 967 /* Destroy an i386 ELF linker hash table. */ 968 969 static void 970 elf_i386_link_hash_table_free (struct bfd_link_hash_table *hash) 971 { 972 struct elf_i386_link_hash_table *htab 973 = (struct elf_i386_link_hash_table *) hash; 974 975 if (htab->loc_hash_table) 976 htab_delete (htab->loc_hash_table); 977 if (htab->loc_hash_memory) 978 objalloc_free ((struct objalloc *) htab->loc_hash_memory); 979 _bfd_elf_link_hash_table_free (hash); 980 } 981 982 /* Create .plt, .rel.plt, .got, .got.plt, .rel.got, .dynbss, and 983 .rel.bss sections in DYNOBJ, and set up shortcuts to them in our 984 hash table. */ 985 986 static bfd_boolean 987 elf_i386_create_dynamic_sections (bfd *dynobj, struct bfd_link_info *info) 988 { 989 struct elf_i386_link_hash_table *htab; 990 991 if (!_bfd_elf_create_dynamic_sections (dynobj, info)) 992 return FALSE; 993 994 htab = elf_i386_hash_table (info); 995 if (htab == NULL) 996 return FALSE; 997 998 htab->sdynbss = bfd_get_linker_section (dynobj, ".dynbss"); 999 if (!info->shared) 1000 htab->srelbss = bfd_get_linker_section (dynobj, ".rel.bss"); 1001 1002 if (!htab->sdynbss 1003 || (!info->shared && !htab->srelbss)) 1004 abort (); 1005 1006 if (get_elf_i386_backend_data (dynobj)->is_vxworks 1007 && !elf_vxworks_create_dynamic_sections (dynobj, info, 1008 &htab->srelplt2)) 1009 return FALSE; 1010 1011 if (!info->no_ld_generated_unwind_info 1012 && htab->plt_eh_frame == NULL 1013 && htab->elf.splt != NULL) 1014 { 1015 flagword flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY 1016 | SEC_HAS_CONTENTS | SEC_IN_MEMORY 1017 | SEC_LINKER_CREATED); 1018 htab->plt_eh_frame 1019 = bfd_make_section_anyway_with_flags (dynobj, ".eh_frame", flags); 1020 if (htab->plt_eh_frame == NULL 1021 || !bfd_set_section_alignment (dynobj, htab->plt_eh_frame, 2)) 1022 return FALSE; 1023 } 1024 1025 return TRUE; 1026 } 1027 1028 /* Copy the extra info we tack onto an elf_link_hash_entry. */ 1029 1030 static void 1031 elf_i386_copy_indirect_symbol (struct bfd_link_info *info, 1032 struct elf_link_hash_entry *dir, 1033 struct elf_link_hash_entry *ind) 1034 { 1035 struct elf_i386_link_hash_entry *edir, *eind; 1036 1037 edir = (struct elf_i386_link_hash_entry *) dir; 1038 eind = (struct elf_i386_link_hash_entry *) ind; 1039 1040 if (eind->dyn_relocs != NULL) 1041 { 1042 if (edir->dyn_relocs != NULL) 1043 { 1044 struct elf_dyn_relocs **pp; 1045 struct elf_dyn_relocs *p; 1046 1047 /* Add reloc counts against the indirect sym to the direct sym 1048 list. Merge any entries against the same section. */ 1049 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; ) 1050 { 1051 struct elf_dyn_relocs *q; 1052 1053 for (q = edir->dyn_relocs; q != NULL; q = q->next) 1054 if (q->sec == p->sec) 1055 { 1056 q->pc_count += p->pc_count; 1057 q->count += p->count; 1058 *pp = p->next; 1059 break; 1060 } 1061 if (q == NULL) 1062 pp = &p->next; 1063 } 1064 *pp = edir->dyn_relocs; 1065 } 1066 1067 edir->dyn_relocs = eind->dyn_relocs; 1068 eind->dyn_relocs = NULL; 1069 } 1070 1071 if (ind->root.type == bfd_link_hash_indirect 1072 && dir->got.refcount <= 0) 1073 { 1074 edir->tls_type = eind->tls_type; 1075 eind->tls_type = GOT_UNKNOWN; 1076 } 1077 1078 if (ELIMINATE_COPY_RELOCS 1079 && ind->root.type != bfd_link_hash_indirect 1080 && dir->dynamic_adjusted) 1081 { 1082 /* If called to transfer flags for a weakdef during processing 1083 of elf_adjust_dynamic_symbol, don't copy non_got_ref. 1084 We clear it ourselves for ELIMINATE_COPY_RELOCS. */ 1085 dir->ref_dynamic |= ind->ref_dynamic; 1086 dir->ref_regular |= ind->ref_regular; 1087 dir->ref_regular_nonweak |= ind->ref_regular_nonweak; 1088 dir->needs_plt |= ind->needs_plt; 1089 dir->pointer_equality_needed |= ind->pointer_equality_needed; 1090 } 1091 else 1092 _bfd_elf_link_hash_copy_indirect (info, dir, ind); 1093 } 1094 1095 /* Return TRUE if the TLS access code sequence support transition 1096 from R_TYPE. */ 1097 1098 static bfd_boolean 1099 elf_i386_check_tls_transition (bfd *abfd, asection *sec, 1100 bfd_byte *contents, 1101 Elf_Internal_Shdr *symtab_hdr, 1102 struct elf_link_hash_entry **sym_hashes, 1103 unsigned int r_type, 1104 const Elf_Internal_Rela *rel, 1105 const Elf_Internal_Rela *relend) 1106 { 1107 unsigned int val, type; 1108 unsigned long r_symndx; 1109 struct elf_link_hash_entry *h; 1110 bfd_vma offset; 1111 1112 /* Get the section contents. */ 1113 if (contents == NULL) 1114 { 1115 if (elf_section_data (sec)->this_hdr.contents != NULL) 1116 contents = elf_section_data (sec)->this_hdr.contents; 1117 else 1118 { 1119 /* FIXME: How to better handle error condition? */ 1120 if (!bfd_malloc_and_get_section (abfd, sec, &contents)) 1121 return FALSE; 1122 1123 /* Cache the section contents for elf_link_input_bfd. */ 1124 elf_section_data (sec)->this_hdr.contents = contents; 1125 } 1126 } 1127 1128 offset = rel->r_offset; 1129 switch (r_type) 1130 { 1131 case R_386_TLS_GD: 1132 case R_386_TLS_LDM: 1133 if (offset < 2 || (rel + 1) >= relend) 1134 return FALSE; 1135 1136 type = bfd_get_8 (abfd, contents + offset - 2); 1137 if (r_type == R_386_TLS_GD) 1138 { 1139 /* Check transition from GD access model. Only 1140 leal foo@tlsgd(,%reg,1), %eax; call ___tls_get_addr 1141 leal foo@tlsgd(%reg), %eax; call ___tls_get_addr; nop 1142 can transit to different access model. */ 1143 if ((offset + 10) > sec->size || 1144 (type != 0x8d && type != 0x04)) 1145 return FALSE; 1146 1147 val = bfd_get_8 (abfd, contents + offset - 1); 1148 if (type == 0x04) 1149 { 1150 /* leal foo@tlsgd(,%reg,1), %eax; call ___tls_get_addr */ 1151 if (offset < 3) 1152 return FALSE; 1153 1154 if (bfd_get_8 (abfd, contents + offset - 3) != 0x8d) 1155 return FALSE; 1156 1157 if ((val & 0xc7) != 0x05 || val == (4 << 3)) 1158 return FALSE; 1159 } 1160 else 1161 { 1162 /* leal foo@tlsgd(%reg), %eax; call ___tls_get_addr; nop */ 1163 if ((val & 0xf8) != 0x80 || (val & 7) == 4) 1164 return FALSE; 1165 1166 if (bfd_get_8 (abfd, contents + offset + 9) != 0x90) 1167 return FALSE; 1168 } 1169 } 1170 else 1171 { 1172 /* Check transition from LD access model. Only 1173 leal foo@tlsgd(%reg), %eax; call ___tls_get_addr 1174 can transit to different access model. */ 1175 if (type != 0x8d || (offset + 9) > sec->size) 1176 return FALSE; 1177 1178 val = bfd_get_8 (abfd, contents + offset - 1); 1179 if ((val & 0xf8) != 0x80 || (val & 7) == 4) 1180 return FALSE; 1181 } 1182 1183 if (bfd_get_8 (abfd, contents + offset + 4) != 0xe8) 1184 return FALSE; 1185 1186 r_symndx = ELF32_R_SYM (rel[1].r_info); 1187 if (r_symndx < symtab_hdr->sh_info) 1188 return FALSE; 1189 1190 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 1191 /* Use strncmp to check ___tls_get_addr since ___tls_get_addr 1192 may be versioned. */ 1193 return (h != NULL 1194 && h->root.root.string != NULL 1195 && (ELF32_R_TYPE (rel[1].r_info) == R_386_PC32 1196 || ELF32_R_TYPE (rel[1].r_info) == R_386_PLT32) 1197 && (strncmp (h->root.root.string, "___tls_get_addr", 1198 15) == 0)); 1199 1200 case R_386_TLS_IE: 1201 /* Check transition from IE access model: 1202 movl foo@indntpoff(%rip), %eax 1203 movl foo@indntpoff(%rip), %reg 1204 addl foo@indntpoff(%rip), %reg 1205 */ 1206 1207 if (offset < 1 || (offset + 4) > sec->size) 1208 return FALSE; 1209 1210 /* Check "movl foo@tpoff(%rip), %eax" first. */ 1211 val = bfd_get_8 (abfd, contents + offset - 1); 1212 if (val == 0xa1) 1213 return TRUE; 1214 1215 if (offset < 2) 1216 return FALSE; 1217 1218 /* Check movl|addl foo@tpoff(%rip), %reg. */ 1219 type = bfd_get_8 (abfd, contents + offset - 2); 1220 return ((type == 0x8b || type == 0x03) 1221 && (val & 0xc7) == 0x05); 1222 1223 case R_386_TLS_GOTIE: 1224 case R_386_TLS_IE_32: 1225 /* Check transition from {IE_32,GOTIE} access model: 1226 subl foo@{tpoff,gontoff}(%reg1), %reg2 1227 movl foo@{tpoff,gontoff}(%reg1), %reg2 1228 addl foo@{tpoff,gontoff}(%reg1), %reg2 1229 */ 1230 1231 if (offset < 2 || (offset + 4) > sec->size) 1232 return FALSE; 1233 1234 val = bfd_get_8 (abfd, contents + offset - 1); 1235 if ((val & 0xc0) != 0x80 || (val & 7) == 4) 1236 return FALSE; 1237 1238 type = bfd_get_8 (abfd, contents + offset - 2); 1239 return type == 0x8b || type == 0x2b || type == 0x03; 1240 1241 case R_386_TLS_GOTDESC: 1242 /* Check transition from GDesc access model: 1243 leal x@tlsdesc(%ebx), %eax 1244 1245 Make sure it's a leal adding ebx to a 32-bit offset 1246 into any register, although it's probably almost always 1247 going to be eax. */ 1248 1249 if (offset < 2 || (offset + 4) > sec->size) 1250 return FALSE; 1251 1252 if (bfd_get_8 (abfd, contents + offset - 2) != 0x8d) 1253 return FALSE; 1254 1255 val = bfd_get_8 (abfd, contents + offset - 1); 1256 return (val & 0xc7) == 0x83; 1257 1258 case R_386_TLS_DESC_CALL: 1259 /* Check transition from GDesc access model: 1260 call *x@tlsdesc(%rax) 1261 */ 1262 if (offset + 2 <= sec->size) 1263 { 1264 /* Make sure that it's a call *x@tlsdesc(%rax). */ 1265 static const unsigned char call[] = { 0xff, 0x10 }; 1266 return memcmp (contents + offset, call, 2) == 0; 1267 } 1268 1269 return FALSE; 1270 1271 default: 1272 abort (); 1273 } 1274 } 1275 1276 /* Return TRUE if the TLS access transition is OK or no transition 1277 will be performed. Update R_TYPE if there is a transition. */ 1278 1279 static bfd_boolean 1280 elf_i386_tls_transition (struct bfd_link_info *info, bfd *abfd, 1281 asection *sec, bfd_byte *contents, 1282 Elf_Internal_Shdr *symtab_hdr, 1283 struct elf_link_hash_entry **sym_hashes, 1284 unsigned int *r_type, int tls_type, 1285 const Elf_Internal_Rela *rel, 1286 const Elf_Internal_Rela *relend, 1287 struct elf_link_hash_entry *h, 1288 unsigned long r_symndx) 1289 { 1290 unsigned int from_type = *r_type; 1291 unsigned int to_type = from_type; 1292 bfd_boolean check = TRUE; 1293 1294 /* Skip TLS transition for functions. */ 1295 if (h != NULL 1296 && (h->type == STT_FUNC 1297 || h->type == STT_GNU_IFUNC)) 1298 return TRUE; 1299 1300 switch (from_type) 1301 { 1302 case R_386_TLS_GD: 1303 case R_386_TLS_GOTDESC: 1304 case R_386_TLS_DESC_CALL: 1305 case R_386_TLS_IE_32: 1306 case R_386_TLS_IE: 1307 case R_386_TLS_GOTIE: 1308 if (info->executable) 1309 { 1310 if (h == NULL) 1311 to_type = R_386_TLS_LE_32; 1312 else if (from_type != R_386_TLS_IE 1313 && from_type != R_386_TLS_GOTIE) 1314 to_type = R_386_TLS_IE_32; 1315 } 1316 1317 /* When we are called from elf_i386_relocate_section, CONTENTS 1318 isn't NULL and there may be additional transitions based on 1319 TLS_TYPE. */ 1320 if (contents != NULL) 1321 { 1322 unsigned int new_to_type = to_type; 1323 1324 if (info->executable 1325 && h != NULL 1326 && h->dynindx == -1 1327 && (tls_type & GOT_TLS_IE)) 1328 new_to_type = R_386_TLS_LE_32; 1329 1330 if (to_type == R_386_TLS_GD 1331 || to_type == R_386_TLS_GOTDESC 1332 || to_type == R_386_TLS_DESC_CALL) 1333 { 1334 if (tls_type == GOT_TLS_IE_POS) 1335 new_to_type = R_386_TLS_GOTIE; 1336 else if (tls_type & GOT_TLS_IE) 1337 new_to_type = R_386_TLS_IE_32; 1338 } 1339 1340 /* We checked the transition before when we were called from 1341 elf_i386_check_relocs. We only want to check the new 1342 transition which hasn't been checked before. */ 1343 check = new_to_type != to_type && from_type == to_type; 1344 to_type = new_to_type; 1345 } 1346 1347 break; 1348 1349 case R_386_TLS_LDM: 1350 if (info->executable) 1351 to_type = R_386_TLS_LE_32; 1352 break; 1353 1354 default: 1355 return TRUE; 1356 } 1357 1358 /* Return TRUE if there is no transition. */ 1359 if (from_type == to_type) 1360 return TRUE; 1361 1362 /* Check if the transition can be performed. */ 1363 if (check 1364 && ! elf_i386_check_tls_transition (abfd, sec, contents, 1365 symtab_hdr, sym_hashes, 1366 from_type, rel, relend)) 1367 { 1368 reloc_howto_type *from, *to; 1369 const char *name; 1370 1371 from = elf_i386_rtype_to_howto (abfd, from_type); 1372 to = elf_i386_rtype_to_howto (abfd, to_type); 1373 1374 if (h) 1375 name = h->root.root.string; 1376 else 1377 { 1378 struct elf_i386_link_hash_table *htab; 1379 1380 htab = elf_i386_hash_table (info); 1381 if (htab == NULL) 1382 name = "*unknown*"; 1383 else 1384 { 1385 Elf_Internal_Sym *isym; 1386 1387 isym = bfd_sym_from_r_symndx (&htab->sym_cache, 1388 abfd, r_symndx); 1389 name = bfd_elf_sym_name (abfd, symtab_hdr, isym, NULL); 1390 } 1391 } 1392 1393 (*_bfd_error_handler) 1394 (_("%B: TLS transition from %s to %s against `%s' at 0x%lx " 1395 "in section `%A' failed"), 1396 abfd, sec, from->name, to->name, name, 1397 (unsigned long) rel->r_offset); 1398 bfd_set_error (bfd_error_bad_value); 1399 return FALSE; 1400 } 1401 1402 *r_type = to_type; 1403 return TRUE; 1404 } 1405 1406 /* Look through the relocs for a section during the first phase, and 1407 calculate needed space in the global offset table, procedure linkage 1408 table, and dynamic reloc sections. */ 1409 1410 static bfd_boolean 1411 elf_i386_check_relocs (bfd *abfd, 1412 struct bfd_link_info *info, 1413 asection *sec, 1414 const Elf_Internal_Rela *relocs) 1415 { 1416 struct elf_i386_link_hash_table *htab; 1417 Elf_Internal_Shdr *symtab_hdr; 1418 struct elf_link_hash_entry **sym_hashes; 1419 const Elf_Internal_Rela *rel; 1420 const Elf_Internal_Rela *rel_end; 1421 asection *sreloc; 1422 1423 if (info->relocatable) 1424 return TRUE; 1425 1426 BFD_ASSERT (is_i386_elf (abfd)); 1427 1428 htab = elf_i386_hash_table (info); 1429 if (htab == NULL) 1430 return FALSE; 1431 1432 symtab_hdr = &elf_symtab_hdr (abfd); 1433 sym_hashes = elf_sym_hashes (abfd); 1434 1435 sreloc = NULL; 1436 1437 rel_end = relocs + sec->reloc_count; 1438 for (rel = relocs; rel < rel_end; rel++) 1439 { 1440 unsigned int r_type; 1441 unsigned long r_symndx; 1442 struct elf_link_hash_entry *h; 1443 Elf_Internal_Sym *isym; 1444 const char *name; 1445 bfd_boolean size_reloc; 1446 1447 r_symndx = ELF32_R_SYM (rel->r_info); 1448 r_type = ELF32_R_TYPE (rel->r_info); 1449 1450 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr)) 1451 { 1452 (*_bfd_error_handler) (_("%B: bad symbol index: %d"), 1453 abfd, 1454 r_symndx); 1455 return FALSE; 1456 } 1457 1458 if (r_symndx < symtab_hdr->sh_info) 1459 { 1460 /* A local symbol. */ 1461 isym = bfd_sym_from_r_symndx (&htab->sym_cache, 1462 abfd, r_symndx); 1463 if (isym == NULL) 1464 return FALSE; 1465 1466 /* Check relocation against local STT_GNU_IFUNC symbol. */ 1467 if (ELF32_ST_TYPE (isym->st_info) == STT_GNU_IFUNC) 1468 { 1469 h = elf_i386_get_local_sym_hash (htab, abfd, rel, TRUE); 1470 if (h == NULL) 1471 return FALSE; 1472 1473 /* Fake a STT_GNU_IFUNC symbol. */ 1474 h->type = STT_GNU_IFUNC; 1475 h->def_regular = 1; 1476 h->ref_regular = 1; 1477 h->forced_local = 1; 1478 h->root.type = bfd_link_hash_defined; 1479 } 1480 else 1481 h = NULL; 1482 } 1483 else 1484 { 1485 isym = NULL; 1486 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 1487 while (h->root.type == bfd_link_hash_indirect 1488 || h->root.type == bfd_link_hash_warning) 1489 h = (struct elf_link_hash_entry *) h->root.u.i.link; 1490 } 1491 1492 if (h != NULL) 1493 { 1494 /* Create the ifunc sections for static executables. If we 1495 never see an indirect function symbol nor we are building 1496 a static executable, those sections will be empty and 1497 won't appear in output. */ 1498 switch (r_type) 1499 { 1500 default: 1501 break; 1502 1503 case R_386_32: 1504 case R_386_PC32: 1505 case R_386_PLT32: 1506 case R_386_GOT32: 1507 case R_386_GOTOFF: 1508 if (htab->elf.dynobj == NULL) 1509 htab->elf.dynobj = abfd; 1510 if (!_bfd_elf_create_ifunc_sections (htab->elf.dynobj, info)) 1511 return FALSE; 1512 break; 1513 } 1514 1515 /* It is referenced by a non-shared object. */ 1516 h->ref_regular = 1; 1517 } 1518 1519 if (! elf_i386_tls_transition (info, abfd, sec, NULL, 1520 symtab_hdr, sym_hashes, 1521 &r_type, GOT_UNKNOWN, 1522 rel, rel_end, h, r_symndx)) 1523 return FALSE; 1524 1525 switch (r_type) 1526 { 1527 case R_386_TLS_LDM: 1528 htab->tls_ldm_got.refcount += 1; 1529 goto create_got; 1530 1531 case R_386_PLT32: 1532 /* This symbol requires a procedure linkage table entry. We 1533 actually build the entry in adjust_dynamic_symbol, 1534 because this might be a case of linking PIC code which is 1535 never referenced by a dynamic object, in which case we 1536 don't need to generate a procedure linkage table entry 1537 after all. */ 1538 1539 /* If this is a local symbol, we resolve it directly without 1540 creating a procedure linkage table entry. */ 1541 if (h == NULL) 1542 continue; 1543 1544 h->needs_plt = 1; 1545 h->plt.refcount += 1; 1546 break; 1547 1548 case R_386_SIZE32: 1549 size_reloc = TRUE; 1550 goto do_size; 1551 1552 case R_386_TLS_IE_32: 1553 case R_386_TLS_IE: 1554 case R_386_TLS_GOTIE: 1555 if (!info->executable) 1556 info->flags |= DF_STATIC_TLS; 1557 /* Fall through */ 1558 1559 case R_386_GOT32: 1560 case R_386_TLS_GD: 1561 case R_386_TLS_GOTDESC: 1562 case R_386_TLS_DESC_CALL: 1563 /* This symbol requires a global offset table entry. */ 1564 { 1565 int tls_type, old_tls_type; 1566 1567 switch (r_type) 1568 { 1569 default: 1570 case R_386_GOT32: tls_type = GOT_NORMAL; break; 1571 case R_386_TLS_GD: tls_type = GOT_TLS_GD; break; 1572 case R_386_TLS_GOTDESC: 1573 case R_386_TLS_DESC_CALL: 1574 tls_type = GOT_TLS_GDESC; break; 1575 case R_386_TLS_IE_32: 1576 if (ELF32_R_TYPE (rel->r_info) == r_type) 1577 tls_type = GOT_TLS_IE_NEG; 1578 else 1579 /* If this is a GD->IE transition, we may use either of 1580 R_386_TLS_TPOFF and R_386_TLS_TPOFF32. */ 1581 tls_type = GOT_TLS_IE; 1582 break; 1583 case R_386_TLS_IE: 1584 case R_386_TLS_GOTIE: 1585 tls_type = GOT_TLS_IE_POS; break; 1586 } 1587 1588 if (h != NULL) 1589 { 1590 h->got.refcount += 1; 1591 old_tls_type = elf_i386_hash_entry(h)->tls_type; 1592 } 1593 else 1594 { 1595 bfd_signed_vma *local_got_refcounts; 1596 1597 /* This is a global offset table entry for a local symbol. */ 1598 local_got_refcounts = elf_local_got_refcounts (abfd); 1599 if (local_got_refcounts == NULL) 1600 { 1601 bfd_size_type size; 1602 1603 size = symtab_hdr->sh_info; 1604 size *= (sizeof (bfd_signed_vma) 1605 + sizeof (bfd_vma) + sizeof(char)); 1606 local_got_refcounts = (bfd_signed_vma *) 1607 bfd_zalloc (abfd, size); 1608 if (local_got_refcounts == NULL) 1609 return FALSE; 1610 elf_local_got_refcounts (abfd) = local_got_refcounts; 1611 elf_i386_local_tlsdesc_gotent (abfd) 1612 = (bfd_vma *) (local_got_refcounts + symtab_hdr->sh_info); 1613 elf_i386_local_got_tls_type (abfd) 1614 = (char *) (local_got_refcounts + 2 * symtab_hdr->sh_info); 1615 } 1616 local_got_refcounts[r_symndx] += 1; 1617 old_tls_type = elf_i386_local_got_tls_type (abfd) [r_symndx]; 1618 } 1619 1620 if ((old_tls_type & GOT_TLS_IE) && (tls_type & GOT_TLS_IE)) 1621 tls_type |= old_tls_type; 1622 /* If a TLS symbol is accessed using IE at least once, 1623 there is no point to use dynamic model for it. */ 1624 else if (old_tls_type != tls_type && old_tls_type != GOT_UNKNOWN 1625 && (! GOT_TLS_GD_ANY_P (old_tls_type) 1626 || (tls_type & GOT_TLS_IE) == 0)) 1627 { 1628 if ((old_tls_type & GOT_TLS_IE) && GOT_TLS_GD_ANY_P (tls_type)) 1629 tls_type = old_tls_type; 1630 else if (GOT_TLS_GD_ANY_P (old_tls_type) 1631 && GOT_TLS_GD_ANY_P (tls_type)) 1632 tls_type |= old_tls_type; 1633 else 1634 { 1635 if (h) 1636 name = h->root.root.string; 1637 else 1638 name = bfd_elf_sym_name (abfd, symtab_hdr, isym, 1639 NULL); 1640 (*_bfd_error_handler) 1641 (_("%B: `%s' accessed both as normal and " 1642 "thread local symbol"), 1643 abfd, name); 1644 bfd_set_error (bfd_error_bad_value); 1645 return FALSE; 1646 } 1647 } 1648 1649 if (old_tls_type != tls_type) 1650 { 1651 if (h != NULL) 1652 elf_i386_hash_entry (h)->tls_type = tls_type; 1653 else 1654 elf_i386_local_got_tls_type (abfd) [r_symndx] = tls_type; 1655 } 1656 } 1657 /* Fall through */ 1658 1659 case R_386_GOTOFF: 1660 case R_386_GOTPC: 1661 create_got: 1662 if (htab->elf.sgot == NULL) 1663 { 1664 if (htab->elf.dynobj == NULL) 1665 htab->elf.dynobj = abfd; 1666 if (!_bfd_elf_create_got_section (htab->elf.dynobj, info)) 1667 return FALSE; 1668 } 1669 if (r_type != R_386_TLS_IE) 1670 break; 1671 /* Fall through */ 1672 1673 case R_386_TLS_LE_32: 1674 case R_386_TLS_LE: 1675 if (info->executable) 1676 break; 1677 info->flags |= DF_STATIC_TLS; 1678 /* Fall through */ 1679 1680 case R_386_32: 1681 case R_386_PC32: 1682 if (h != NULL && info->executable) 1683 { 1684 /* If this reloc is in a read-only section, we might 1685 need a copy reloc. We can't check reliably at this 1686 stage whether the section is read-only, as input 1687 sections have not yet been mapped to output sections. 1688 Tentatively set the flag for now, and correct in 1689 adjust_dynamic_symbol. */ 1690 h->non_got_ref = 1; 1691 1692 /* We may need a .plt entry if the function this reloc 1693 refers to is in a shared lib. */ 1694 h->plt.refcount += 1; 1695 if (r_type != R_386_PC32) 1696 h->pointer_equality_needed = 1; 1697 } 1698 1699 size_reloc = FALSE; 1700 do_size: 1701 /* If we are creating a shared library, and this is a reloc 1702 against a global symbol, or a non PC relative reloc 1703 against a local symbol, then we need to copy the reloc 1704 into the shared library. However, if we are linking with 1705 -Bsymbolic, we do not need to copy a reloc against a 1706 global symbol which is defined in an object we are 1707 including in the link (i.e., DEF_REGULAR is set). At 1708 this point we have not seen all the input files, so it is 1709 possible that DEF_REGULAR is not set now but will be set 1710 later (it is never cleared). In case of a weak definition, 1711 DEF_REGULAR may be cleared later by a strong definition in 1712 a shared library. We account for that possibility below by 1713 storing information in the relocs_copied field of the hash 1714 table entry. A similar situation occurs when creating 1715 shared libraries and symbol visibility changes render the 1716 symbol local. 1717 1718 If on the other hand, we are creating an executable, we 1719 may need to keep relocations for symbols satisfied by a 1720 dynamic library if we manage to avoid copy relocs for the 1721 symbol. */ 1722 if ((info->shared 1723 && (sec->flags & SEC_ALLOC) != 0 1724 && (r_type != R_386_PC32 1725 || (h != NULL 1726 && (! SYMBOLIC_BIND (info, h) 1727 || h->root.type == bfd_link_hash_defweak 1728 || !h->def_regular)))) 1729 || (ELIMINATE_COPY_RELOCS 1730 && !info->shared 1731 && (sec->flags & SEC_ALLOC) != 0 1732 && h != NULL 1733 && (h->root.type == bfd_link_hash_defweak 1734 || !h->def_regular))) 1735 { 1736 struct elf_dyn_relocs *p; 1737 struct elf_dyn_relocs **head; 1738 1739 /* We must copy these reloc types into the output file. 1740 Create a reloc section in dynobj and make room for 1741 this reloc. */ 1742 if (sreloc == NULL) 1743 { 1744 if (htab->elf.dynobj == NULL) 1745 htab->elf.dynobj = abfd; 1746 1747 sreloc = _bfd_elf_make_dynamic_reloc_section 1748 (sec, htab->elf.dynobj, 2, abfd, /*rela?*/ FALSE); 1749 1750 if (sreloc == NULL) 1751 return FALSE; 1752 } 1753 1754 /* If this is a global symbol, we count the number of 1755 relocations we need for this symbol. */ 1756 if (h != NULL) 1757 { 1758 head = &((struct elf_i386_link_hash_entry *) h)->dyn_relocs; 1759 } 1760 else 1761 { 1762 /* Track dynamic relocs needed for local syms too. 1763 We really need local syms available to do this 1764 easily. Oh well. */ 1765 void **vpp; 1766 asection *s; 1767 1768 isym = bfd_sym_from_r_symndx (&htab->sym_cache, 1769 abfd, r_symndx); 1770 if (isym == NULL) 1771 return FALSE; 1772 1773 s = bfd_section_from_elf_index (abfd, isym->st_shndx); 1774 if (s == NULL) 1775 s = sec; 1776 1777 vpp = &elf_section_data (s)->local_dynrel; 1778 head = (struct elf_dyn_relocs **)vpp; 1779 } 1780 1781 p = *head; 1782 if (p == NULL || p->sec != sec) 1783 { 1784 bfd_size_type amt = sizeof *p; 1785 p = (struct elf_dyn_relocs *) bfd_alloc (htab->elf.dynobj, 1786 amt); 1787 if (p == NULL) 1788 return FALSE; 1789 p->next = *head; 1790 *head = p; 1791 p->sec = sec; 1792 p->count = 0; 1793 p->pc_count = 0; 1794 } 1795 1796 p->count += 1; 1797 /* Count size relocation as PC-relative relocation. */ 1798 if (r_type == R_386_PC32 || size_reloc) 1799 p->pc_count += 1; 1800 } 1801 break; 1802 1803 /* This relocation describes the C++ object vtable hierarchy. 1804 Reconstruct it for later use during GC. */ 1805 case R_386_GNU_VTINHERIT: 1806 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset)) 1807 return FALSE; 1808 break; 1809 1810 /* This relocation describes which C++ vtable entries are actually 1811 used. Record for later use during GC. */ 1812 case R_386_GNU_VTENTRY: 1813 BFD_ASSERT (h != NULL); 1814 if (h != NULL 1815 && !bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_offset)) 1816 return FALSE; 1817 break; 1818 1819 default: 1820 break; 1821 } 1822 } 1823 1824 return TRUE; 1825 } 1826 1827 /* Return the section that should be marked against GC for a given 1828 relocation. */ 1829 1830 static asection * 1831 elf_i386_gc_mark_hook (asection *sec, 1832 struct bfd_link_info *info, 1833 Elf_Internal_Rela *rel, 1834 struct elf_link_hash_entry *h, 1835 Elf_Internal_Sym *sym) 1836 { 1837 if (h != NULL) 1838 switch (ELF32_R_TYPE (rel->r_info)) 1839 { 1840 case R_386_GNU_VTINHERIT: 1841 case R_386_GNU_VTENTRY: 1842 return NULL; 1843 } 1844 1845 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym); 1846 } 1847 1848 /* Update the got entry reference counts for the section being removed. */ 1849 1850 static bfd_boolean 1851 elf_i386_gc_sweep_hook (bfd *abfd, 1852 struct bfd_link_info *info, 1853 asection *sec, 1854 const Elf_Internal_Rela *relocs) 1855 { 1856 struct elf_i386_link_hash_table *htab; 1857 Elf_Internal_Shdr *symtab_hdr; 1858 struct elf_link_hash_entry **sym_hashes; 1859 bfd_signed_vma *local_got_refcounts; 1860 const Elf_Internal_Rela *rel, *relend; 1861 1862 if (info->relocatable) 1863 return TRUE; 1864 1865 htab = elf_i386_hash_table (info); 1866 if (htab == NULL) 1867 return FALSE; 1868 1869 elf_section_data (sec)->local_dynrel = NULL; 1870 1871 symtab_hdr = &elf_symtab_hdr (abfd); 1872 sym_hashes = elf_sym_hashes (abfd); 1873 local_got_refcounts = elf_local_got_refcounts (abfd); 1874 1875 relend = relocs + sec->reloc_count; 1876 for (rel = relocs; rel < relend; rel++) 1877 { 1878 unsigned long r_symndx; 1879 unsigned int r_type; 1880 struct elf_link_hash_entry *h = NULL; 1881 1882 r_symndx = ELF32_R_SYM (rel->r_info); 1883 if (r_symndx >= symtab_hdr->sh_info) 1884 { 1885 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 1886 while (h->root.type == bfd_link_hash_indirect 1887 || h->root.type == bfd_link_hash_warning) 1888 h = (struct elf_link_hash_entry *) h->root.u.i.link; 1889 } 1890 else 1891 { 1892 /* A local symbol. */ 1893 Elf_Internal_Sym *isym; 1894 1895 isym = bfd_sym_from_r_symndx (&htab->sym_cache, 1896 abfd, r_symndx); 1897 1898 /* Check relocation against local STT_GNU_IFUNC symbol. */ 1899 if (isym != NULL 1900 && ELF32_ST_TYPE (isym->st_info) == STT_GNU_IFUNC) 1901 { 1902 h = elf_i386_get_local_sym_hash (htab, abfd, rel, FALSE); 1903 if (h == NULL) 1904 abort (); 1905 } 1906 } 1907 1908 if (h) 1909 { 1910 struct elf_i386_link_hash_entry *eh; 1911 struct elf_dyn_relocs **pp; 1912 struct elf_dyn_relocs *p; 1913 1914 eh = (struct elf_i386_link_hash_entry *) h; 1915 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next) 1916 if (p->sec == sec) 1917 { 1918 /* Everything must go for SEC. */ 1919 *pp = p->next; 1920 break; 1921 } 1922 } 1923 1924 r_type = ELF32_R_TYPE (rel->r_info); 1925 if (! elf_i386_tls_transition (info, abfd, sec, NULL, 1926 symtab_hdr, sym_hashes, 1927 &r_type, GOT_UNKNOWN, 1928 rel, relend, h, r_symndx)) 1929 return FALSE; 1930 1931 switch (r_type) 1932 { 1933 case R_386_TLS_LDM: 1934 if (htab->tls_ldm_got.refcount > 0) 1935 htab->tls_ldm_got.refcount -= 1; 1936 break; 1937 1938 case R_386_TLS_GD: 1939 case R_386_TLS_GOTDESC: 1940 case R_386_TLS_DESC_CALL: 1941 case R_386_TLS_IE_32: 1942 case R_386_TLS_IE: 1943 case R_386_TLS_GOTIE: 1944 case R_386_GOT32: 1945 if (h != NULL) 1946 { 1947 if (h->got.refcount > 0) 1948 h->got.refcount -= 1; 1949 if (h->type == STT_GNU_IFUNC) 1950 { 1951 if (h->plt.refcount > 0) 1952 h->plt.refcount -= 1; 1953 } 1954 } 1955 else if (local_got_refcounts != NULL) 1956 { 1957 if (local_got_refcounts[r_symndx] > 0) 1958 local_got_refcounts[r_symndx] -= 1; 1959 } 1960 break; 1961 1962 case R_386_32: 1963 case R_386_PC32: 1964 case R_386_SIZE32: 1965 if (info->shared 1966 && (h == NULL || h->type != STT_GNU_IFUNC)) 1967 break; 1968 /* Fall through */ 1969 1970 case R_386_PLT32: 1971 if (h != NULL) 1972 { 1973 if (h->plt.refcount > 0) 1974 h->plt.refcount -= 1; 1975 } 1976 break; 1977 1978 case R_386_GOTOFF: 1979 if (h != NULL && h->type == STT_GNU_IFUNC) 1980 { 1981 if (h->got.refcount > 0) 1982 h->got.refcount -= 1; 1983 if (h->plt.refcount > 0) 1984 h->plt.refcount -= 1; 1985 } 1986 break; 1987 1988 default: 1989 break; 1990 } 1991 } 1992 1993 return TRUE; 1994 } 1995 1996 /* Adjust a symbol defined by a dynamic object and referenced by a 1997 regular object. The current definition is in some section of the 1998 dynamic object, but we're not including those sections. We have to 1999 change the definition to something the rest of the link can 2000 understand. */ 2001 2002 static bfd_boolean 2003 elf_i386_adjust_dynamic_symbol (struct bfd_link_info *info, 2004 struct elf_link_hash_entry *h) 2005 { 2006 struct elf_i386_link_hash_table *htab; 2007 asection *s; 2008 struct elf_i386_link_hash_entry *eh; 2009 struct elf_dyn_relocs *p; 2010 2011 /* STT_GNU_IFUNC symbol must go through PLT. */ 2012 if (h->type == STT_GNU_IFUNC) 2013 { 2014 /* All local STT_GNU_IFUNC references must be treate as local 2015 calls via local PLT. */ 2016 if (h->ref_regular 2017 && SYMBOL_CALLS_LOCAL (info, h)) 2018 { 2019 bfd_size_type pc_count = 0, count = 0; 2020 struct elf_dyn_relocs **pp; 2021 2022 eh = (struct elf_i386_link_hash_entry *) h; 2023 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; ) 2024 { 2025 pc_count += p->pc_count; 2026 p->count -= p->pc_count; 2027 p->pc_count = 0; 2028 count += p->count; 2029 if (p->count == 0) 2030 *pp = p->next; 2031 else 2032 pp = &p->next; 2033 } 2034 2035 if (pc_count || count) 2036 { 2037 h->needs_plt = 1; 2038 h->non_got_ref = 1; 2039 if (h->plt.refcount <= 0) 2040 h->plt.refcount = 1; 2041 else 2042 h->plt.refcount += 1; 2043 } 2044 } 2045 2046 if (h->plt.refcount <= 0) 2047 { 2048 h->plt.offset = (bfd_vma) -1; 2049 h->needs_plt = 0; 2050 } 2051 return TRUE; 2052 } 2053 2054 /* If this is a function, put it in the procedure linkage table. We 2055 will fill in the contents of the procedure linkage table later, 2056 when we know the address of the .got section. */ 2057 if (h->type == STT_FUNC 2058 || h->needs_plt) 2059 { 2060 if (h->plt.refcount <= 0 2061 || SYMBOL_CALLS_LOCAL (info, h) 2062 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT 2063 && h->root.type == bfd_link_hash_undefweak)) 2064 { 2065 /* This case can occur if we saw a PLT32 reloc in an input 2066 file, but the symbol was never referred to by a dynamic 2067 object, or if all references were garbage collected. In 2068 such a case, we don't actually need to build a procedure 2069 linkage table, and we can just do a PC32 reloc instead. */ 2070 h->plt.offset = (bfd_vma) -1; 2071 h->needs_plt = 0; 2072 } 2073 2074 return TRUE; 2075 } 2076 else 2077 /* It's possible that we incorrectly decided a .plt reloc was 2078 needed for an R_386_PC32 reloc to a non-function sym in 2079 check_relocs. We can't decide accurately between function and 2080 non-function syms in check-relocs; Objects loaded later in 2081 the link may change h->type. So fix it now. */ 2082 h->plt.offset = (bfd_vma) -1; 2083 2084 /* If this is a weak symbol, and there is a real definition, the 2085 processor independent code will have arranged for us to see the 2086 real definition first, and we can just use the same value. */ 2087 if (h->u.weakdef != NULL) 2088 { 2089 BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined 2090 || h->u.weakdef->root.type == bfd_link_hash_defweak); 2091 h->root.u.def.section = h->u.weakdef->root.u.def.section; 2092 h->root.u.def.value = h->u.weakdef->root.u.def.value; 2093 if (ELIMINATE_COPY_RELOCS || info->nocopyreloc) 2094 h->non_got_ref = h->u.weakdef->non_got_ref; 2095 return TRUE; 2096 } 2097 2098 /* This is a reference to a symbol defined by a dynamic object which 2099 is not a function. */ 2100 2101 /* If we are creating a shared library, we must presume that the 2102 only references to the symbol are via the global offset table. 2103 For such cases we need not do anything here; the relocations will 2104 be handled correctly by relocate_section. */ 2105 if (info->shared) 2106 return TRUE; 2107 2108 /* If there are no references to this symbol that do not use the 2109 GOT, we don't need to generate a copy reloc. */ 2110 if (!h->non_got_ref) 2111 return TRUE; 2112 2113 /* If -z nocopyreloc was given, we won't generate them either. */ 2114 if (info->nocopyreloc) 2115 { 2116 h->non_got_ref = 0; 2117 return TRUE; 2118 } 2119 2120 htab = elf_i386_hash_table (info); 2121 if (htab == NULL) 2122 return FALSE; 2123 2124 /* If there aren't any dynamic relocs in read-only sections, then 2125 we can keep the dynamic relocs and avoid the copy reloc. This 2126 doesn't work on VxWorks, where we can not have dynamic relocations 2127 (other than copy and jump slot relocations) in an executable. */ 2128 if (ELIMINATE_COPY_RELOCS 2129 && !get_elf_i386_backend_data (info->output_bfd)->is_vxworks) 2130 { 2131 eh = (struct elf_i386_link_hash_entry *) h; 2132 for (p = eh->dyn_relocs; p != NULL; p = p->next) 2133 { 2134 s = p->sec->output_section; 2135 if (s != NULL && (s->flags & SEC_READONLY) != 0) 2136 break; 2137 } 2138 2139 if (p == NULL) 2140 { 2141 h->non_got_ref = 0; 2142 return TRUE; 2143 } 2144 } 2145 2146 /* We must allocate the symbol in our .dynbss section, which will 2147 become part of the .bss section of the executable. There will be 2148 an entry for this symbol in the .dynsym section. The dynamic 2149 object will contain position independent code, so all references 2150 from the dynamic object to this symbol will go through the global 2151 offset table. The dynamic linker will use the .dynsym entry to 2152 determine the address it must put in the global offset table, so 2153 both the dynamic object and the regular object will refer to the 2154 same memory location for the variable. */ 2155 2156 /* We must generate a R_386_COPY reloc to tell the dynamic linker to 2157 copy the initial value out of the dynamic object and into the 2158 runtime process image. */ 2159 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0) 2160 { 2161 htab->srelbss->size += sizeof (Elf32_External_Rel); 2162 h->needs_copy = 1; 2163 } 2164 2165 s = htab->sdynbss; 2166 2167 return _bfd_elf_adjust_dynamic_copy (h, s); 2168 } 2169 2170 /* Allocate space in .plt, .got and associated reloc sections for 2171 dynamic relocs. */ 2172 2173 static bfd_boolean 2174 elf_i386_allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf) 2175 { 2176 struct bfd_link_info *info; 2177 struct elf_i386_link_hash_table *htab; 2178 struct elf_i386_link_hash_entry *eh; 2179 struct elf_dyn_relocs *p; 2180 unsigned plt_entry_size; 2181 2182 if (h->root.type == bfd_link_hash_indirect) 2183 return TRUE; 2184 2185 eh = (struct elf_i386_link_hash_entry *) h; 2186 2187 info = (struct bfd_link_info *) inf; 2188 htab = elf_i386_hash_table (info); 2189 if (htab == NULL) 2190 return FALSE; 2191 2192 plt_entry_size = GET_PLT_ENTRY_SIZE (info->output_bfd); 2193 2194 /* Since STT_GNU_IFUNC symbol must go through PLT, we handle it 2195 here if it is defined and referenced in a non-shared object. */ 2196 if (h->type == STT_GNU_IFUNC 2197 && h->def_regular) 2198 return _bfd_elf_allocate_ifunc_dyn_relocs (info, h, &eh->dyn_relocs, 2199 plt_entry_size, 4); 2200 else if (htab->elf.dynamic_sections_created 2201 && h->plt.refcount > 0) 2202 { 2203 /* Make sure this symbol is output as a dynamic symbol. 2204 Undefined weak syms won't yet be marked as dynamic. */ 2205 if (h->dynindx == -1 2206 && !h->forced_local) 2207 { 2208 if (! bfd_elf_link_record_dynamic_symbol (info, h)) 2209 return FALSE; 2210 } 2211 2212 if (info->shared 2213 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h)) 2214 { 2215 asection *s = htab->elf.splt; 2216 2217 /* If this is the first .plt entry, make room for the special 2218 first entry. */ 2219 if (s->size == 0) 2220 s->size += plt_entry_size; 2221 2222 h->plt.offset = s->size; 2223 2224 /* If this symbol is not defined in a regular file, and we are 2225 not generating a shared library, then set the symbol to this 2226 location in the .plt. This is required to make function 2227 pointers compare as equal between the normal executable and 2228 the shared library. */ 2229 if (! info->shared 2230 && !h->def_regular) 2231 { 2232 h->root.u.def.section = s; 2233 h->root.u.def.value = h->plt.offset; 2234 } 2235 2236 /* Make room for this entry. */ 2237 s->size += plt_entry_size; 2238 2239 /* We also need to make an entry in the .got.plt section, which 2240 will be placed in the .got section by the linker script. */ 2241 htab->elf.sgotplt->size += 4; 2242 2243 /* We also need to make an entry in the .rel.plt section. */ 2244 htab->elf.srelplt->size += sizeof (Elf32_External_Rel); 2245 htab->elf.srelplt->reloc_count++; 2246 2247 if (get_elf_i386_backend_data (info->output_bfd)->is_vxworks 2248 && !info->shared) 2249 { 2250 /* VxWorks has a second set of relocations for each PLT entry 2251 in executables. They go in a separate relocation section, 2252 which is processed by the kernel loader. */ 2253 2254 /* There are two relocations for the initial PLT entry: an 2255 R_386_32 relocation for _GLOBAL_OFFSET_TABLE_ + 4 and an 2256 R_386_32 relocation for _GLOBAL_OFFSET_TABLE_ + 8. */ 2257 2258 if (h->plt.offset == plt_entry_size) 2259 htab->srelplt2->size += (sizeof (Elf32_External_Rel) * 2); 2260 2261 /* There are two extra relocations for each subsequent PLT entry: 2262 an R_386_32 relocation for the GOT entry, and an R_386_32 2263 relocation for the PLT entry. */ 2264 2265 htab->srelplt2->size += (sizeof (Elf32_External_Rel) * 2); 2266 } 2267 } 2268 else 2269 { 2270 h->plt.offset = (bfd_vma) -1; 2271 h->needs_plt = 0; 2272 } 2273 } 2274 else 2275 { 2276 h->plt.offset = (bfd_vma) -1; 2277 h->needs_plt = 0; 2278 } 2279 2280 eh->tlsdesc_got = (bfd_vma) -1; 2281 2282 /* If R_386_TLS_{IE_32,IE,GOTIE} symbol is now local to the binary, 2283 make it a R_386_TLS_LE_32 requiring no TLS entry. */ 2284 if (h->got.refcount > 0 2285 && info->executable 2286 && h->dynindx == -1 2287 && (elf_i386_hash_entry(h)->tls_type & GOT_TLS_IE)) 2288 h->got.offset = (bfd_vma) -1; 2289 else if (h->got.refcount > 0) 2290 { 2291 asection *s; 2292 bfd_boolean dyn; 2293 int tls_type = elf_i386_hash_entry(h)->tls_type; 2294 2295 /* Make sure this symbol is output as a dynamic symbol. 2296 Undefined weak syms won't yet be marked as dynamic. */ 2297 if (h->dynindx == -1 2298 && !h->forced_local) 2299 { 2300 if (! bfd_elf_link_record_dynamic_symbol (info, h)) 2301 return FALSE; 2302 } 2303 2304 s = htab->elf.sgot; 2305 if (GOT_TLS_GDESC_P (tls_type)) 2306 { 2307 eh->tlsdesc_got = htab->elf.sgotplt->size 2308 - elf_i386_compute_jump_table_size (htab); 2309 htab->elf.sgotplt->size += 8; 2310 h->got.offset = (bfd_vma) -2; 2311 } 2312 if (! GOT_TLS_GDESC_P (tls_type) 2313 || GOT_TLS_GD_P (tls_type)) 2314 { 2315 h->got.offset = s->size; 2316 s->size += 4; 2317 /* R_386_TLS_GD needs 2 consecutive GOT slots. */ 2318 if (GOT_TLS_GD_P (tls_type) || tls_type == GOT_TLS_IE_BOTH) 2319 s->size += 4; 2320 } 2321 dyn = htab->elf.dynamic_sections_created; 2322 /* R_386_TLS_IE_32 needs one dynamic relocation, 2323 R_386_TLS_IE resp. R_386_TLS_GOTIE needs one dynamic relocation, 2324 (but if both R_386_TLS_IE_32 and R_386_TLS_IE is present, we 2325 need two), R_386_TLS_GD needs one if local symbol and two if 2326 global. */ 2327 if (tls_type == GOT_TLS_IE_BOTH) 2328 htab->elf.srelgot->size += 2 * sizeof (Elf32_External_Rel); 2329 else if ((GOT_TLS_GD_P (tls_type) && h->dynindx == -1) 2330 || (tls_type & GOT_TLS_IE)) 2331 htab->elf.srelgot->size += sizeof (Elf32_External_Rel); 2332 else if (GOT_TLS_GD_P (tls_type)) 2333 htab->elf.srelgot->size += 2 * sizeof (Elf32_External_Rel); 2334 else if (! GOT_TLS_GDESC_P (tls_type) 2335 && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT 2336 || h->root.type != bfd_link_hash_undefweak) 2337 && (info->shared 2338 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h))) 2339 htab->elf.srelgot->size += sizeof (Elf32_External_Rel); 2340 if (GOT_TLS_GDESC_P (tls_type)) 2341 htab->elf.srelplt->size += sizeof (Elf32_External_Rel); 2342 } 2343 else 2344 h->got.offset = (bfd_vma) -1; 2345 2346 if (eh->dyn_relocs == NULL) 2347 return TRUE; 2348 2349 /* In the shared -Bsymbolic case, discard space allocated for 2350 dynamic pc-relative relocs against symbols which turn out to be 2351 defined in regular objects. For the normal shared case, discard 2352 space for pc-relative relocs that have become local due to symbol 2353 visibility changes. */ 2354 2355 if (info->shared) 2356 { 2357 /* The only reloc that uses pc_count is R_386_PC32, which will 2358 appear on a call or on something like ".long foo - .". We 2359 want calls to protected symbols to resolve directly to the 2360 function rather than going via the plt. If people want 2361 function pointer comparisons to work as expected then they 2362 should avoid writing assembly like ".long foo - .". */ 2363 if (SYMBOL_CALLS_LOCAL (info, h)) 2364 { 2365 struct elf_dyn_relocs **pp; 2366 2367 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; ) 2368 { 2369 p->count -= p->pc_count; 2370 p->pc_count = 0; 2371 if (p->count == 0) 2372 *pp = p->next; 2373 else 2374 pp = &p->next; 2375 } 2376 } 2377 2378 if (get_elf_i386_backend_data (info->output_bfd)->is_vxworks) 2379 { 2380 struct elf_dyn_relocs **pp; 2381 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; ) 2382 { 2383 if (strcmp (p->sec->output_section->name, ".tls_vars") == 0) 2384 *pp = p->next; 2385 else 2386 pp = &p->next; 2387 } 2388 } 2389 2390 /* Also discard relocs on undefined weak syms with non-default 2391 visibility. */ 2392 if (eh->dyn_relocs != NULL 2393 && h->root.type == bfd_link_hash_undefweak) 2394 { 2395 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT) 2396 eh->dyn_relocs = NULL; 2397 2398 /* Make sure undefined weak symbols are output as a dynamic 2399 symbol in PIEs. */ 2400 else if (h->dynindx == -1 2401 && !h->forced_local) 2402 { 2403 if (! bfd_elf_link_record_dynamic_symbol (info, h)) 2404 return FALSE; 2405 } 2406 } 2407 } 2408 else if (ELIMINATE_COPY_RELOCS) 2409 { 2410 /* For the non-shared case, discard space for relocs against 2411 symbols which turn out to need copy relocs or are not 2412 dynamic. */ 2413 2414 if (!h->non_got_ref 2415 && ((h->def_dynamic 2416 && !h->def_regular) 2417 || (htab->elf.dynamic_sections_created 2418 && (h->root.type == bfd_link_hash_undefweak 2419 || h->root.type == bfd_link_hash_undefined)))) 2420 { 2421 /* Make sure this symbol is output as a dynamic symbol. 2422 Undefined weak syms won't yet be marked as dynamic. */ 2423 if (h->dynindx == -1 2424 && !h->forced_local) 2425 { 2426 if (! bfd_elf_link_record_dynamic_symbol (info, h)) 2427 return FALSE; 2428 } 2429 2430 /* If that succeeded, we know we'll be keeping all the 2431 relocs. */ 2432 if (h->dynindx != -1) 2433 goto keep; 2434 } 2435 2436 eh->dyn_relocs = NULL; 2437 2438 keep: ; 2439 } 2440 2441 /* Finally, allocate space. */ 2442 for (p = eh->dyn_relocs; p != NULL; p = p->next) 2443 { 2444 asection *sreloc; 2445 2446 sreloc = elf_section_data (p->sec)->sreloc; 2447 2448 BFD_ASSERT (sreloc != NULL); 2449 sreloc->size += p->count * sizeof (Elf32_External_Rel); 2450 } 2451 2452 return TRUE; 2453 } 2454 2455 /* Allocate space in .plt, .got and associated reloc sections for 2456 local dynamic relocs. */ 2457 2458 static bfd_boolean 2459 elf_i386_allocate_local_dynrelocs (void **slot, void *inf) 2460 { 2461 struct elf_link_hash_entry *h 2462 = (struct elf_link_hash_entry *) *slot; 2463 2464 if (h->type != STT_GNU_IFUNC 2465 || !h->def_regular 2466 || !h->ref_regular 2467 || !h->forced_local 2468 || h->root.type != bfd_link_hash_defined) 2469 abort (); 2470 2471 return elf_i386_allocate_dynrelocs (h, inf); 2472 } 2473 2474 /* Find any dynamic relocs that apply to read-only sections. */ 2475 2476 static bfd_boolean 2477 elf_i386_readonly_dynrelocs (struct elf_link_hash_entry *h, void *inf) 2478 { 2479 struct elf_i386_link_hash_entry *eh; 2480 struct elf_dyn_relocs *p; 2481 2482 /* Skip local IFUNC symbols. */ 2483 if (h->forced_local && h->type == STT_GNU_IFUNC) 2484 return TRUE; 2485 2486 eh = (struct elf_i386_link_hash_entry *) h; 2487 for (p = eh->dyn_relocs; p != NULL; p = p->next) 2488 { 2489 asection *s = p->sec->output_section; 2490 2491 if (s != NULL && (s->flags & SEC_READONLY) != 0) 2492 { 2493 struct bfd_link_info *info = (struct bfd_link_info *) inf; 2494 2495 info->flags |= DF_TEXTREL; 2496 2497 if (info->warn_shared_textrel && info->shared) 2498 info->callbacks->einfo (_("%P: %B: warning: relocation against `%s' in readonly section `%A'.\n"), 2499 p->sec->owner, h->root.root.string, 2500 p->sec); 2501 2502 /* Not an error, just cut short the traversal. */ 2503 return FALSE; 2504 } 2505 } 2506 return TRUE; 2507 } 2508 2509 /* Convert 2510 mov foo@GOT(%reg), %reg 2511 to 2512 lea foo@GOTOFF(%reg), %reg 2513 with the local symbol, foo. */ 2514 2515 static bfd_boolean 2516 elf_i386_convert_mov_to_lea (bfd *abfd, asection *sec, 2517 struct bfd_link_info *link_info) 2518 { 2519 Elf_Internal_Shdr *symtab_hdr; 2520 Elf_Internal_Rela *internal_relocs; 2521 Elf_Internal_Rela *irel, *irelend; 2522 bfd_byte *contents; 2523 struct elf_i386_link_hash_table *htab; 2524 bfd_boolean changed_contents; 2525 bfd_boolean changed_relocs; 2526 bfd_signed_vma *local_got_refcounts; 2527 2528 /* Don't even try to convert non-ELF outputs. */ 2529 if (!is_elf_hash_table (link_info->hash)) 2530 return FALSE; 2531 2532 /* Nothing to do if there are no codes, no relocations or no output. */ 2533 if ((sec->flags & (SEC_CODE | SEC_RELOC)) != (SEC_CODE | SEC_RELOC) 2534 || sec->reloc_count == 0 2535 || discarded_section (sec)) 2536 return TRUE; 2537 2538 symtab_hdr = &elf_tdata (abfd)->symtab_hdr; 2539 2540 /* Load the relocations for this section. */ 2541 internal_relocs = (_bfd_elf_link_read_relocs 2542 (abfd, sec, NULL, (Elf_Internal_Rela *) NULL, 2543 link_info->keep_memory)); 2544 if (internal_relocs == NULL) 2545 return FALSE; 2546 2547 htab = elf_i386_hash_table (link_info); 2548 changed_contents = FALSE; 2549 changed_relocs = FALSE; 2550 local_got_refcounts = elf_local_got_refcounts (abfd); 2551 2552 /* Get the section contents. */ 2553 if (elf_section_data (sec)->this_hdr.contents != NULL) 2554 contents = elf_section_data (sec)->this_hdr.contents; 2555 else 2556 { 2557 if (!bfd_malloc_and_get_section (abfd, sec, &contents)) 2558 goto error_return; 2559 } 2560 2561 irelend = internal_relocs + sec->reloc_count; 2562 for (irel = internal_relocs; irel < irelend; irel++) 2563 { 2564 unsigned int r_type = ELF32_R_TYPE (irel->r_info); 2565 unsigned int r_symndx = ELF32_R_SYM (irel->r_info); 2566 unsigned int indx; 2567 struct elf_link_hash_entry *h; 2568 2569 if (r_type != R_386_GOT32) 2570 continue; 2571 2572 /* Get the symbol referred to by the reloc. */ 2573 if (r_symndx < symtab_hdr->sh_info) 2574 { 2575 Elf_Internal_Sym *isym; 2576 2577 isym = bfd_sym_from_r_symndx (&htab->sym_cache, 2578 abfd, r_symndx); 2579 2580 /* STT_GNU_IFUNC must keep R_386_GOT32 relocation. */ 2581 if (ELF_ST_TYPE (isym->st_info) != STT_GNU_IFUNC 2582 && bfd_get_8 (input_bfd, 2583 contents + irel->r_offset - 2) == 0x8b) 2584 { 2585 bfd_put_8 (output_bfd, 0x8d, 2586 contents + irel->r_offset - 2); 2587 irel->r_info = ELF32_R_INFO (r_symndx, R_386_GOTOFF); 2588 if (local_got_refcounts != NULL 2589 && local_got_refcounts[r_symndx] > 0) 2590 local_got_refcounts[r_symndx] -= 1; 2591 changed_contents = TRUE; 2592 changed_relocs = TRUE; 2593 } 2594 continue; 2595 } 2596 2597 indx = r_symndx - symtab_hdr->sh_info; 2598 h = elf_sym_hashes (abfd)[indx]; 2599 BFD_ASSERT (h != NULL); 2600 2601 while (h->root.type == bfd_link_hash_indirect 2602 || h->root.type == bfd_link_hash_warning) 2603 h = (struct elf_link_hash_entry *) h->root.u.i.link; 2604 2605 /* STT_GNU_IFUNC must keep R_386_GOT32 relocation. We also avoid 2606 optimizing _DYNAMIC since ld.so may use its link-time address. */ 2607 if (h->def_regular 2608 && h->type != STT_GNU_IFUNC 2609 && h != htab->elf.hdynamic 2610 && SYMBOL_REFERENCES_LOCAL (link_info, h) 2611 && bfd_get_8 (input_bfd, 2612 contents + irel->r_offset - 2) == 0x8b) 2613 { 2614 bfd_put_8 (output_bfd, 0x8d, 2615 contents + irel->r_offset - 2); 2616 irel->r_info = ELF32_R_INFO (r_symndx, R_386_GOTOFF); 2617 if (h->got.refcount > 0) 2618 h->got.refcount -= 1; 2619 changed_contents = TRUE; 2620 changed_relocs = TRUE; 2621 } 2622 } 2623 2624 if (contents != NULL 2625 && elf_section_data (sec)->this_hdr.contents != contents) 2626 { 2627 if (!changed_contents && !link_info->keep_memory) 2628 free (contents); 2629 else 2630 { 2631 /* Cache the section contents for elf_link_input_bfd. */ 2632 elf_section_data (sec)->this_hdr.contents = contents; 2633 } 2634 } 2635 2636 if (elf_section_data (sec)->relocs != internal_relocs) 2637 { 2638 if (!changed_relocs) 2639 free (internal_relocs); 2640 else 2641 elf_section_data (sec)->relocs = internal_relocs; 2642 } 2643 2644 return TRUE; 2645 2646 error_return: 2647 if (contents != NULL 2648 && elf_section_data (sec)->this_hdr.contents != contents) 2649 free (contents); 2650 if (internal_relocs != NULL 2651 && elf_section_data (sec)->relocs != internal_relocs) 2652 free (internal_relocs); 2653 return FALSE; 2654 } 2655 2656 /* Set the sizes of the dynamic sections. */ 2657 2658 static bfd_boolean 2659 elf_i386_size_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info) 2660 { 2661 struct elf_i386_link_hash_table *htab; 2662 bfd *dynobj; 2663 asection *s; 2664 bfd_boolean relocs; 2665 bfd *ibfd; 2666 2667 htab = elf_i386_hash_table (info); 2668 if (htab == NULL) 2669 return FALSE; 2670 dynobj = htab->elf.dynobj; 2671 if (dynobj == NULL) 2672 abort (); 2673 2674 if (htab->elf.dynamic_sections_created) 2675 { 2676 /* Set the contents of the .interp section to the interpreter. */ 2677 if (info->executable) 2678 { 2679 s = bfd_get_linker_section (dynobj, ".interp"); 2680 if (s == NULL) 2681 abort (); 2682 s->size = sizeof ELF_DYNAMIC_INTERPRETER; 2683 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER; 2684 } 2685 } 2686 2687 /* Set up .got offsets for local syms, and space for local dynamic 2688 relocs. */ 2689 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next) 2690 { 2691 bfd_signed_vma *local_got; 2692 bfd_signed_vma *end_local_got; 2693 char *local_tls_type; 2694 bfd_vma *local_tlsdesc_gotent; 2695 bfd_size_type locsymcount; 2696 Elf_Internal_Shdr *symtab_hdr; 2697 asection *srel; 2698 2699 if (! is_i386_elf (ibfd)) 2700 continue; 2701 2702 for (s = ibfd->sections; s != NULL; s = s->next) 2703 { 2704 struct elf_dyn_relocs *p; 2705 2706 if (!elf_i386_convert_mov_to_lea (ibfd, s, info)) 2707 return FALSE; 2708 2709 for (p = ((struct elf_dyn_relocs *) 2710 elf_section_data (s)->local_dynrel); 2711 p != NULL; 2712 p = p->next) 2713 { 2714 if (!bfd_is_abs_section (p->sec) 2715 && bfd_is_abs_section (p->sec->output_section)) 2716 { 2717 /* Input section has been discarded, either because 2718 it is a copy of a linkonce section or due to 2719 linker script /DISCARD/, so we'll be discarding 2720 the relocs too. */ 2721 } 2722 else if (get_elf_i386_backend_data (output_bfd)->is_vxworks 2723 && strcmp (p->sec->output_section->name, 2724 ".tls_vars") == 0) 2725 { 2726 /* Relocations in vxworks .tls_vars sections are 2727 handled specially by the loader. */ 2728 } 2729 else if (p->count != 0) 2730 { 2731 srel = elf_section_data (p->sec)->sreloc; 2732 srel->size += p->count * sizeof (Elf32_External_Rel); 2733 if ((p->sec->output_section->flags & SEC_READONLY) != 0 2734 && (info->flags & DF_TEXTREL) == 0) 2735 { 2736 info->flags |= DF_TEXTREL; 2737 if (info->warn_shared_textrel && info->shared) 2738 info->callbacks->einfo (_("%P: %B: warning: relocation in readonly section `%A'.\n"), 2739 p->sec->owner, p->sec); 2740 } 2741 } 2742 } 2743 } 2744 2745 local_got = elf_local_got_refcounts (ibfd); 2746 if (!local_got) 2747 continue; 2748 2749 symtab_hdr = &elf_symtab_hdr (ibfd); 2750 locsymcount = symtab_hdr->sh_info; 2751 end_local_got = local_got + locsymcount; 2752 local_tls_type = elf_i386_local_got_tls_type (ibfd); 2753 local_tlsdesc_gotent = elf_i386_local_tlsdesc_gotent (ibfd); 2754 s = htab->elf.sgot; 2755 srel = htab->elf.srelgot; 2756 for (; local_got < end_local_got; 2757 ++local_got, ++local_tls_type, ++local_tlsdesc_gotent) 2758 { 2759 *local_tlsdesc_gotent = (bfd_vma) -1; 2760 if (*local_got > 0) 2761 { 2762 if (GOT_TLS_GDESC_P (*local_tls_type)) 2763 { 2764 *local_tlsdesc_gotent = htab->elf.sgotplt->size 2765 - elf_i386_compute_jump_table_size (htab); 2766 htab->elf.sgotplt->size += 8; 2767 *local_got = (bfd_vma) -2; 2768 } 2769 if (! GOT_TLS_GDESC_P (*local_tls_type) 2770 || GOT_TLS_GD_P (*local_tls_type)) 2771 { 2772 *local_got = s->size; 2773 s->size += 4; 2774 if (GOT_TLS_GD_P (*local_tls_type) 2775 || *local_tls_type == GOT_TLS_IE_BOTH) 2776 s->size += 4; 2777 } 2778 if (info->shared 2779 || GOT_TLS_GD_ANY_P (*local_tls_type) 2780 || (*local_tls_type & GOT_TLS_IE)) 2781 { 2782 if (*local_tls_type == GOT_TLS_IE_BOTH) 2783 srel->size += 2 * sizeof (Elf32_External_Rel); 2784 else if (GOT_TLS_GD_P (*local_tls_type) 2785 || ! GOT_TLS_GDESC_P (*local_tls_type)) 2786 srel->size += sizeof (Elf32_External_Rel); 2787 if (GOT_TLS_GDESC_P (*local_tls_type)) 2788 htab->elf.srelplt->size += sizeof (Elf32_External_Rel); 2789 } 2790 } 2791 else 2792 *local_got = (bfd_vma) -1; 2793 } 2794 } 2795 2796 if (htab->tls_ldm_got.refcount > 0) 2797 { 2798 /* Allocate 2 got entries and 1 dynamic reloc for R_386_TLS_LDM 2799 relocs. */ 2800 htab->tls_ldm_got.offset = htab->elf.sgot->size; 2801 htab->elf.sgot->size += 8; 2802 htab->elf.srelgot->size += sizeof (Elf32_External_Rel); 2803 } 2804 else 2805 htab->tls_ldm_got.offset = -1; 2806 2807 /* Allocate global sym .plt and .got entries, and space for global 2808 sym dynamic relocs. */ 2809 elf_link_hash_traverse (&htab->elf, elf_i386_allocate_dynrelocs, info); 2810 2811 /* Allocate .plt and .got entries, and space for local symbols. */ 2812 htab_traverse (htab->loc_hash_table, 2813 elf_i386_allocate_local_dynrelocs, 2814 info); 2815 2816 /* For every jump slot reserved in the sgotplt, reloc_count is 2817 incremented. However, when we reserve space for TLS descriptors, 2818 it's not incremented, so in order to compute the space reserved 2819 for them, it suffices to multiply the reloc count by the jump 2820 slot size. 2821 2822 PR ld/13302: We start next_irelative_index at the end of .rela.plt 2823 so that R_386_IRELATIVE entries come last. */ 2824 if (htab->elf.srelplt) 2825 { 2826 htab->next_tls_desc_index = htab->elf.srelplt->reloc_count; 2827 htab->sgotplt_jump_table_size = htab->next_tls_desc_index * 4; 2828 htab->next_irelative_index = htab->elf.srelplt->reloc_count - 1; 2829 } 2830 else if (htab->elf.irelplt) 2831 htab->next_irelative_index = htab->elf.irelplt->reloc_count - 1; 2832 2833 2834 if (htab->elf.sgotplt) 2835 { 2836 /* Don't allocate .got.plt section if there are no GOT nor PLT 2837 entries and there is no reference to _GLOBAL_OFFSET_TABLE_. */ 2838 if ((htab->elf.hgot == NULL 2839 || !htab->elf.hgot->ref_regular_nonweak) 2840 && (htab->elf.sgotplt->size 2841 == get_elf_backend_data (output_bfd)->got_header_size) 2842 && (htab->elf.splt == NULL 2843 || htab->elf.splt->size == 0) 2844 && (htab->elf.sgot == NULL 2845 || htab->elf.sgot->size == 0) 2846 && (htab->elf.iplt == NULL 2847 || htab->elf.iplt->size == 0) 2848 && (htab->elf.igotplt == NULL 2849 || htab->elf.igotplt->size == 0)) 2850 htab->elf.sgotplt->size = 0; 2851 } 2852 2853 2854 if (htab->plt_eh_frame != NULL 2855 && htab->elf.splt != NULL 2856 && htab->elf.splt->size != 0 2857 && !bfd_is_abs_section (htab->elf.splt->output_section) 2858 && _bfd_elf_eh_frame_present (info)) 2859 htab->plt_eh_frame->size = sizeof (elf_i386_eh_frame_plt); 2860 2861 /* We now have determined the sizes of the various dynamic sections. 2862 Allocate memory for them. */ 2863 relocs = FALSE; 2864 for (s = dynobj->sections; s != NULL; s = s->next) 2865 { 2866 bfd_boolean strip_section = TRUE; 2867 2868 if ((s->flags & SEC_LINKER_CREATED) == 0) 2869 continue; 2870 2871 if (s == htab->elf.splt 2872 || s == htab->elf.sgot) 2873 { 2874 /* Strip this section if we don't need it; see the 2875 comment below. */ 2876 /* We'd like to strip these sections if they aren't needed, but if 2877 we've exported dynamic symbols from them we must leave them. 2878 It's too late to tell BFD to get rid of the symbols. */ 2879 2880 if (htab->elf.hplt != NULL) 2881 strip_section = FALSE; 2882 } 2883 else if (s == htab->elf.sgotplt 2884 || s == htab->elf.iplt 2885 || s == htab->elf.igotplt 2886 || s == htab->plt_eh_frame 2887 || s == htab->sdynbss) 2888 { 2889 /* Strip these too. */ 2890 } 2891 else if (CONST_STRNEQ (bfd_get_section_name (dynobj, s), ".rel")) 2892 { 2893 if (s->size != 0 2894 && s != htab->elf.srelplt 2895 && s != htab->srelplt2) 2896 relocs = TRUE; 2897 2898 /* We use the reloc_count field as a counter if we need 2899 to copy relocs into the output file. */ 2900 s->reloc_count = 0; 2901 } 2902 else 2903 { 2904 /* It's not one of our sections, so don't allocate space. */ 2905 continue; 2906 } 2907 2908 if (s->size == 0) 2909 { 2910 /* If we don't need this section, strip it from the 2911 output file. This is mostly to handle .rel.bss and 2912 .rel.plt. We must create both sections in 2913 create_dynamic_sections, because they must be created 2914 before the linker maps input sections to output 2915 sections. The linker does that before 2916 adjust_dynamic_symbol is called, and it is that 2917 function which decides whether anything needs to go 2918 into these sections. */ 2919 if (strip_section) 2920 s->flags |= SEC_EXCLUDE; 2921 continue; 2922 } 2923 2924 if ((s->flags & SEC_HAS_CONTENTS) == 0) 2925 continue; 2926 2927 /* Allocate memory for the section contents. We use bfd_zalloc 2928 here in case unused entries are not reclaimed before the 2929 section's contents are written out. This should not happen, 2930 but this way if it does, we get a R_386_NONE reloc instead 2931 of garbage. */ 2932 s->contents = (unsigned char *) bfd_zalloc (dynobj, s->size); 2933 if (s->contents == NULL) 2934 return FALSE; 2935 } 2936 2937 if (htab->plt_eh_frame != NULL 2938 && htab->plt_eh_frame->contents != NULL) 2939 { 2940 memcpy (htab->plt_eh_frame->contents, elf_i386_eh_frame_plt, 2941 sizeof (elf_i386_eh_frame_plt)); 2942 bfd_put_32 (dynobj, htab->elf.splt->size, 2943 htab->plt_eh_frame->contents + PLT_FDE_LEN_OFFSET); 2944 } 2945 2946 if (htab->elf.dynamic_sections_created) 2947 { 2948 /* Add some entries to the .dynamic section. We fill in the 2949 values later, in elf_i386_finish_dynamic_sections, but we 2950 must add the entries now so that we get the correct size for 2951 the .dynamic section. The DT_DEBUG entry is filled in by the 2952 dynamic linker and used by the debugger. */ 2953 #define add_dynamic_entry(TAG, VAL) \ 2954 _bfd_elf_add_dynamic_entry (info, TAG, VAL) 2955 2956 if (info->executable) 2957 { 2958 if (!add_dynamic_entry (DT_DEBUG, 0)) 2959 return FALSE; 2960 } 2961 2962 if (htab->elf.splt->size != 0) 2963 { 2964 if (!add_dynamic_entry (DT_PLTGOT, 0) 2965 || !add_dynamic_entry (DT_PLTRELSZ, 0) 2966 || !add_dynamic_entry (DT_PLTREL, DT_REL) 2967 || !add_dynamic_entry (DT_JMPREL, 0)) 2968 return FALSE; 2969 } 2970 2971 if (relocs) 2972 { 2973 if (!add_dynamic_entry (DT_REL, 0) 2974 || !add_dynamic_entry (DT_RELSZ, 0) 2975 || !add_dynamic_entry (DT_RELENT, sizeof (Elf32_External_Rel))) 2976 return FALSE; 2977 2978 /* If any dynamic relocs apply to a read-only section, 2979 then we need a DT_TEXTREL entry. */ 2980 if ((info->flags & DF_TEXTREL) == 0) 2981 elf_link_hash_traverse (&htab->elf, 2982 elf_i386_readonly_dynrelocs, info); 2983 2984 if ((info->flags & DF_TEXTREL) != 0) 2985 { 2986 if (!add_dynamic_entry (DT_TEXTREL, 0)) 2987 return FALSE; 2988 } 2989 } 2990 if (get_elf_i386_backend_data (output_bfd)->is_vxworks 2991 && !elf_vxworks_add_dynamic_entries (output_bfd, info)) 2992 return FALSE; 2993 } 2994 #undef add_dynamic_entry 2995 2996 return TRUE; 2997 } 2998 2999 static bfd_boolean 3000 elf_i386_always_size_sections (bfd *output_bfd, 3001 struct bfd_link_info *info) 3002 { 3003 asection *tls_sec = elf_hash_table (info)->tls_sec; 3004 3005 if (tls_sec) 3006 { 3007 struct elf_link_hash_entry *tlsbase; 3008 3009 tlsbase = elf_link_hash_lookup (elf_hash_table (info), 3010 "_TLS_MODULE_BASE_", 3011 FALSE, FALSE, FALSE); 3012 3013 if (tlsbase && tlsbase->type == STT_TLS) 3014 { 3015 struct elf_i386_link_hash_table *htab; 3016 struct bfd_link_hash_entry *bh = NULL; 3017 const struct elf_backend_data *bed 3018 = get_elf_backend_data (output_bfd); 3019 3020 htab = elf_i386_hash_table (info); 3021 if (htab == NULL) 3022 return FALSE; 3023 3024 if (!(_bfd_generic_link_add_one_symbol 3025 (info, output_bfd, "_TLS_MODULE_BASE_", BSF_LOCAL, 3026 tls_sec, 0, NULL, FALSE, 3027 bed->collect, &bh))) 3028 return FALSE; 3029 3030 htab->tls_module_base = bh; 3031 3032 tlsbase = (struct elf_link_hash_entry *)bh; 3033 tlsbase->def_regular = 1; 3034 tlsbase->other = STV_HIDDEN; 3035 (*bed->elf_backend_hide_symbol) (info, tlsbase, TRUE); 3036 } 3037 } 3038 3039 return TRUE; 3040 } 3041 3042 /* Set the correct type for an x86 ELF section. We do this by the 3043 section name, which is a hack, but ought to work. */ 3044 3045 static bfd_boolean 3046 elf_i386_fake_sections (bfd *abfd ATTRIBUTE_UNUSED, 3047 Elf_Internal_Shdr *hdr, 3048 asection *sec) 3049 { 3050 const char *name; 3051 3052 name = bfd_get_section_name (abfd, sec); 3053 3054 /* This is an ugly, but unfortunately necessary hack that is 3055 needed when producing EFI binaries on x86. It tells 3056 elf.c:elf_fake_sections() not to consider ".reloc" as a section 3057 containing ELF relocation info. We need this hack in order to 3058 be able to generate ELF binaries that can be translated into 3059 EFI applications (which are essentially COFF objects). Those 3060 files contain a COFF ".reloc" section inside an ELFNN object, 3061 which would normally cause BFD to segfault because it would 3062 attempt to interpret this section as containing relocation 3063 entries for section "oc". With this hack enabled, ".reloc" 3064 will be treated as a normal data section, which will avoid the 3065 segfault. However, you won't be able to create an ELFNN binary 3066 with a section named "oc" that needs relocations, but that's 3067 the kind of ugly side-effects you get when detecting section 3068 types based on their names... In practice, this limitation is 3069 unlikely to bite. */ 3070 if (strcmp (name, ".reloc") == 0) 3071 hdr->sh_type = SHT_PROGBITS; 3072 3073 return TRUE; 3074 } 3075 3076 /* _TLS_MODULE_BASE_ needs to be treated especially when linking 3077 executables. Rather than setting it to the beginning of the TLS 3078 section, we have to set it to the end. This function may be called 3079 multiple times, it is idempotent. */ 3080 3081 static void 3082 elf_i386_set_tls_module_base (struct bfd_link_info *info) 3083 { 3084 struct elf_i386_link_hash_table *htab; 3085 struct bfd_link_hash_entry *base; 3086 3087 if (!info->executable) 3088 return; 3089 3090 htab = elf_i386_hash_table (info); 3091 if (htab == NULL) 3092 return; 3093 3094 base = htab->tls_module_base; 3095 if (base == NULL) 3096 return; 3097 3098 base->u.def.value = htab->elf.tls_size; 3099 } 3100 3101 /* Return the base VMA address which should be subtracted from real addresses 3102 when resolving @dtpoff relocation. 3103 This is PT_TLS segment p_vaddr. */ 3104 3105 static bfd_vma 3106 elf_i386_dtpoff_base (struct bfd_link_info *info) 3107 { 3108 /* If tls_sec is NULL, we should have signalled an error already. */ 3109 if (elf_hash_table (info)->tls_sec == NULL) 3110 return 0; 3111 return elf_hash_table (info)->tls_sec->vma; 3112 } 3113 3114 /* Return the relocation value for @tpoff relocation 3115 if STT_TLS virtual address is ADDRESS. */ 3116 3117 static bfd_vma 3118 elf_i386_tpoff (struct bfd_link_info *info, bfd_vma address) 3119 { 3120 struct elf_link_hash_table *htab = elf_hash_table (info); 3121 const struct elf_backend_data *bed = get_elf_backend_data (info->output_bfd); 3122 bfd_vma static_tls_size; 3123 3124 /* If tls_sec is NULL, we should have signalled an error already. */ 3125 if (htab->tls_sec == NULL) 3126 return 0; 3127 3128 /* Consider special static TLS alignment requirements. */ 3129 static_tls_size = BFD_ALIGN (htab->tls_size, bed->static_tls_alignment); 3130 return static_tls_size + htab->tls_sec->vma - address; 3131 } 3132 3133 /* Relocate an i386 ELF section. */ 3134 3135 static bfd_boolean 3136 elf_i386_relocate_section (bfd *output_bfd, 3137 struct bfd_link_info *info, 3138 bfd *input_bfd, 3139 asection *input_section, 3140 bfd_byte *contents, 3141 Elf_Internal_Rela *relocs, 3142 Elf_Internal_Sym *local_syms, 3143 asection **local_sections) 3144 { 3145 struct elf_i386_link_hash_table *htab; 3146 Elf_Internal_Shdr *symtab_hdr; 3147 struct elf_link_hash_entry **sym_hashes; 3148 bfd_vma *local_got_offsets; 3149 bfd_vma *local_tlsdesc_gotents; 3150 Elf_Internal_Rela *rel; 3151 Elf_Internal_Rela *relend; 3152 bfd_boolean is_vxworks_tls; 3153 unsigned plt_entry_size; 3154 3155 BFD_ASSERT (is_i386_elf (input_bfd)); 3156 3157 htab = elf_i386_hash_table (info); 3158 if (htab == NULL) 3159 return FALSE; 3160 symtab_hdr = &elf_symtab_hdr (input_bfd); 3161 sym_hashes = elf_sym_hashes (input_bfd); 3162 local_got_offsets = elf_local_got_offsets (input_bfd); 3163 local_tlsdesc_gotents = elf_i386_local_tlsdesc_gotent (input_bfd); 3164 /* We have to handle relocations in vxworks .tls_vars sections 3165 specially, because the dynamic loader is 'weird'. */ 3166 is_vxworks_tls = (get_elf_i386_backend_data (output_bfd)->is_vxworks 3167 && info->shared 3168 && !strcmp (input_section->output_section->name, 3169 ".tls_vars")); 3170 3171 elf_i386_set_tls_module_base (info); 3172 3173 plt_entry_size = GET_PLT_ENTRY_SIZE (output_bfd); 3174 3175 rel = relocs; 3176 relend = relocs + input_section->reloc_count; 3177 for (; rel < relend; rel++) 3178 { 3179 unsigned int r_type; 3180 reloc_howto_type *howto; 3181 unsigned long r_symndx; 3182 struct elf_link_hash_entry *h; 3183 Elf_Internal_Sym *sym; 3184 asection *sec; 3185 bfd_vma off, offplt; 3186 bfd_vma relocation; 3187 bfd_boolean unresolved_reloc; 3188 bfd_reloc_status_type r; 3189 unsigned int indx; 3190 int tls_type; 3191 bfd_vma st_size; 3192 3193 r_type = ELF32_R_TYPE (rel->r_info); 3194 if (r_type == R_386_GNU_VTINHERIT 3195 || r_type == R_386_GNU_VTENTRY) 3196 continue; 3197 3198 if ((indx = r_type) >= R_386_standard 3199 && ((indx = r_type - R_386_ext_offset) - R_386_standard 3200 >= R_386_ext - R_386_standard) 3201 && ((indx = r_type - R_386_tls_offset) - R_386_ext 3202 >= R_386_irelative - R_386_ext)) 3203 { 3204 (*_bfd_error_handler) 3205 (_("%B: unrecognized relocation (0x%x) in section `%A'"), 3206 input_bfd, input_section, r_type); 3207 bfd_set_error (bfd_error_bad_value); 3208 return FALSE; 3209 } 3210 howto = elf_howto_table + indx; 3211 3212 r_symndx = ELF32_R_SYM (rel->r_info); 3213 h = NULL; 3214 sym = NULL; 3215 sec = NULL; 3216 unresolved_reloc = FALSE; 3217 if (r_symndx < symtab_hdr->sh_info) 3218 { 3219 sym = local_syms + r_symndx; 3220 sec = local_sections[r_symndx]; 3221 relocation = (sec->output_section->vma 3222 + sec->output_offset 3223 + sym->st_value); 3224 st_size = sym->st_size; 3225 3226 if (ELF_ST_TYPE (sym->st_info) == STT_SECTION 3227 && ((sec->flags & SEC_MERGE) != 0 3228 || (info->relocatable 3229 && sec->output_offset != 0))) 3230 { 3231 bfd_vma addend; 3232 bfd_byte *where = contents + rel->r_offset; 3233 3234 switch (howto->size) 3235 { 3236 case 0: 3237 addend = bfd_get_8 (input_bfd, where); 3238 if (howto->pc_relative) 3239 { 3240 addend = (addend ^ 0x80) - 0x80; 3241 addend += 1; 3242 } 3243 break; 3244 case 1: 3245 addend = bfd_get_16 (input_bfd, where); 3246 if (howto->pc_relative) 3247 { 3248 addend = (addend ^ 0x8000) - 0x8000; 3249 addend += 2; 3250 } 3251 break; 3252 case 2: 3253 addend = bfd_get_32 (input_bfd, where); 3254 if (howto->pc_relative) 3255 { 3256 addend = (addend ^ 0x80000000) - 0x80000000; 3257 addend += 4; 3258 } 3259 break; 3260 default: 3261 abort (); 3262 } 3263 3264 if (info->relocatable) 3265 addend += sec->output_offset; 3266 else 3267 { 3268 asection *msec = sec; 3269 addend = _bfd_elf_rel_local_sym (output_bfd, sym, &msec, 3270 addend); 3271 addend -= relocation; 3272 addend += msec->output_section->vma + msec->output_offset; 3273 } 3274 3275 switch (howto->size) 3276 { 3277 case 0: 3278 /* FIXME: overflow checks. */ 3279 if (howto->pc_relative) 3280 addend -= 1; 3281 bfd_put_8 (input_bfd, addend, where); 3282 break; 3283 case 1: 3284 if (howto->pc_relative) 3285 addend -= 2; 3286 bfd_put_16 (input_bfd, addend, where); 3287 break; 3288 case 2: 3289 if (howto->pc_relative) 3290 addend -= 4; 3291 bfd_put_32 (input_bfd, addend, where); 3292 break; 3293 } 3294 } 3295 else if (!info->relocatable 3296 && ELF32_ST_TYPE (sym->st_info) == STT_GNU_IFUNC) 3297 { 3298 /* Relocate against local STT_GNU_IFUNC symbol. */ 3299 h = elf_i386_get_local_sym_hash (htab, input_bfd, rel, 3300 FALSE); 3301 if (h == NULL) 3302 abort (); 3303 3304 /* Set STT_GNU_IFUNC symbol value. */ 3305 h->root.u.def.value = sym->st_value; 3306 h->root.u.def.section = sec; 3307 } 3308 } 3309 else 3310 { 3311 bfd_boolean warned ATTRIBUTE_UNUSED; 3312 3313 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel, 3314 r_symndx, symtab_hdr, sym_hashes, 3315 h, sec, relocation, 3316 unresolved_reloc, warned); 3317 st_size = h->size; 3318 } 3319 3320 if (sec != NULL && discarded_section (sec)) 3321 RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section, 3322 rel, 1, relend, howto, 0, contents); 3323 3324 if (info->relocatable) 3325 continue; 3326 3327 /* Since STT_GNU_IFUNC symbol must go through PLT, we handle 3328 it here if it is defined in a non-shared object. */ 3329 if (h != NULL 3330 && h->type == STT_GNU_IFUNC 3331 && h->def_regular) 3332 { 3333 asection *plt, *gotplt, *base_got; 3334 bfd_vma plt_index; 3335 const char *name; 3336 3337 if ((input_section->flags & SEC_ALLOC) == 0 3338 || h->plt.offset == (bfd_vma) -1) 3339 abort (); 3340 3341 /* STT_GNU_IFUNC symbol must go through PLT. */ 3342 if (htab->elf.splt != NULL) 3343 { 3344 plt = htab->elf.splt; 3345 gotplt = htab->elf.sgotplt; 3346 } 3347 else 3348 { 3349 plt = htab->elf.iplt; 3350 gotplt = htab->elf.igotplt; 3351 } 3352 3353 relocation = (plt->output_section->vma 3354 + plt->output_offset + h->plt.offset); 3355 3356 switch (r_type) 3357 { 3358 default: 3359 if (h->root.root.string) 3360 name = h->root.root.string; 3361 else 3362 name = bfd_elf_sym_name (input_bfd, symtab_hdr, sym, 3363 NULL); 3364 (*_bfd_error_handler) 3365 (_("%B: relocation %s against STT_GNU_IFUNC " 3366 "symbol `%s' isn't handled by %s"), input_bfd, 3367 elf_howto_table[r_type].name, 3368 name, __FUNCTION__); 3369 bfd_set_error (bfd_error_bad_value); 3370 return FALSE; 3371 3372 case R_386_32: 3373 /* Generate dynamic relcoation only when there is a 3374 non-GOT reference in a shared object. */ 3375 if (info->shared && h->non_got_ref) 3376 { 3377 Elf_Internal_Rela outrel; 3378 asection *sreloc; 3379 bfd_vma offset; 3380 3381 /* Need a dynamic relocation to get the real function 3382 adddress. */ 3383 offset = _bfd_elf_section_offset (output_bfd, 3384 info, 3385 input_section, 3386 rel->r_offset); 3387 if (offset == (bfd_vma) -1 3388 || offset == (bfd_vma) -2) 3389 abort (); 3390 3391 outrel.r_offset = (input_section->output_section->vma 3392 + input_section->output_offset 3393 + offset); 3394 3395 if (h->dynindx == -1 3396 || h->forced_local 3397 || info->executable) 3398 { 3399 /* This symbol is resolved locally. */ 3400 outrel.r_info = ELF32_R_INFO (0, R_386_IRELATIVE); 3401 bfd_put_32 (output_bfd, 3402 (h->root.u.def.value 3403 + h->root.u.def.section->output_section->vma 3404 + h->root.u.def.section->output_offset), 3405 contents + offset); 3406 } 3407 else 3408 outrel.r_info = ELF32_R_INFO (h->dynindx, r_type); 3409 3410 sreloc = htab->elf.irelifunc; 3411 elf_append_rel (output_bfd, sreloc, &outrel); 3412 3413 /* If this reloc is against an external symbol, we 3414 do not want to fiddle with the addend. Otherwise, 3415 we need to include the symbol value so that it 3416 becomes an addend for the dynamic reloc. For an 3417 internal symbol, we have updated addend. */ 3418 continue; 3419 } 3420 /* FALLTHROUGH */ 3421 case R_386_PC32: 3422 case R_386_PLT32: 3423 goto do_relocation; 3424 3425 case R_386_GOT32: 3426 base_got = htab->elf.sgot; 3427 off = h->got.offset; 3428 3429 if (base_got == NULL) 3430 abort (); 3431 3432 if (off == (bfd_vma) -1) 3433 { 3434 /* We can't use h->got.offset here to save state, or 3435 even just remember the offset, as finish_dynamic_symbol 3436 would use that as offset into .got. */ 3437 3438 if (htab->elf.splt != NULL) 3439 { 3440 plt_index = h->plt.offset / plt_entry_size - 1; 3441 off = (plt_index + 3) * 4; 3442 base_got = htab->elf.sgotplt; 3443 } 3444 else 3445 { 3446 plt_index = h->plt.offset / plt_entry_size; 3447 off = plt_index * 4; 3448 base_got = htab->elf.igotplt; 3449 } 3450 3451 if (h->dynindx == -1 3452 || h->forced_local 3453 || info->symbolic) 3454 { 3455 /* This references the local defitionion. We must 3456 initialize this entry in the global offset table. 3457 Since the offset must always be a multiple of 8, 3458 we use the least significant bit to record 3459 whether we have initialized it already. 3460 3461 When doing a dynamic link, we create a .rela.got 3462 relocation entry to initialize the value. This 3463 is done in the finish_dynamic_symbol routine. */ 3464 if ((off & 1) != 0) 3465 off &= ~1; 3466 else 3467 { 3468 bfd_put_32 (output_bfd, relocation, 3469 base_got->contents + off); 3470 h->got.offset |= 1; 3471 } 3472 } 3473 3474 relocation = off; 3475 3476 /* Adjust for static executables. */ 3477 if (htab->elf.splt == NULL) 3478 relocation += gotplt->output_offset; 3479 } 3480 else 3481 { 3482 relocation = (base_got->output_section->vma 3483 + base_got->output_offset + off 3484 - gotplt->output_section->vma 3485 - gotplt->output_offset); 3486 /* Adjust for static executables. */ 3487 if (htab->elf.splt == NULL) 3488 relocation += gotplt->output_offset; 3489 } 3490 3491 goto do_relocation; 3492 3493 case R_386_GOTOFF: 3494 relocation -= (gotplt->output_section->vma 3495 + gotplt->output_offset); 3496 goto do_relocation; 3497 } 3498 } 3499 3500 switch (r_type) 3501 { 3502 case R_386_GOT32: 3503 /* Relocation is to the entry for this symbol in the global 3504 offset table. */ 3505 if (htab->elf.sgot == NULL) 3506 abort (); 3507 3508 if (h != NULL) 3509 { 3510 bfd_boolean dyn; 3511 3512 off = h->got.offset; 3513 dyn = htab->elf.dynamic_sections_created; 3514 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info->shared, h) 3515 || (info->shared 3516 && SYMBOL_REFERENCES_LOCAL (info, h)) 3517 || (ELF_ST_VISIBILITY (h->other) 3518 && h->root.type == bfd_link_hash_undefweak)) 3519 { 3520 /* This is actually a static link, or it is a 3521 -Bsymbolic link and the symbol is defined 3522 locally, or the symbol was forced to be local 3523 because of a version file. We must initialize 3524 this entry in the global offset table. Since the 3525 offset must always be a multiple of 4, we use the 3526 least significant bit to record whether we have 3527 initialized it already. 3528 3529 When doing a dynamic link, we create a .rel.got 3530 relocation entry to initialize the value. This 3531 is done in the finish_dynamic_symbol routine. */ 3532 if ((off & 1) != 0) 3533 off &= ~1; 3534 else 3535 { 3536 bfd_put_32 (output_bfd, relocation, 3537 htab->elf.sgot->contents + off); 3538 h->got.offset |= 1; 3539 } 3540 } 3541 else 3542 unresolved_reloc = FALSE; 3543 } 3544 else 3545 { 3546 if (local_got_offsets == NULL) 3547 abort (); 3548 3549 off = local_got_offsets[r_symndx]; 3550 3551 /* The offset must always be a multiple of 4. We use 3552 the least significant bit to record whether we have 3553 already generated the necessary reloc. */ 3554 if ((off & 1) != 0) 3555 off &= ~1; 3556 else 3557 { 3558 bfd_put_32 (output_bfd, relocation, 3559 htab->elf.sgot->contents + off); 3560 3561 if (info->shared) 3562 { 3563 asection *s; 3564 Elf_Internal_Rela outrel; 3565 3566 s = htab->elf.srelgot; 3567 if (s == NULL) 3568 abort (); 3569 3570 outrel.r_offset = (htab->elf.sgot->output_section->vma 3571 + htab->elf.sgot->output_offset 3572 + off); 3573 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE); 3574 elf_append_rel (output_bfd, s, &outrel); 3575 } 3576 3577 local_got_offsets[r_symndx] |= 1; 3578 } 3579 } 3580 3581 if (off >= (bfd_vma) -2) 3582 abort (); 3583 3584 relocation = htab->elf.sgot->output_section->vma 3585 + htab->elf.sgot->output_offset + off 3586 - htab->elf.sgotplt->output_section->vma 3587 - htab->elf.sgotplt->output_offset; 3588 break; 3589 3590 case R_386_GOTOFF: 3591 /* Relocation is relative to the start of the global offset 3592 table. */ 3593 3594 /* Check to make sure it isn't a protected function symbol 3595 for shared library since it may not be local when used 3596 as function address. We also need to make sure that a 3597 symbol is defined locally. */ 3598 if (info->shared && h) 3599 { 3600 if (!h->def_regular) 3601 { 3602 const char *v; 3603 3604 switch (ELF_ST_VISIBILITY (h->other)) 3605 { 3606 case STV_HIDDEN: 3607 v = _("hidden symbol"); 3608 break; 3609 case STV_INTERNAL: 3610 v = _("internal symbol"); 3611 break; 3612 case STV_PROTECTED: 3613 v = _("protected symbol"); 3614 break; 3615 default: 3616 v = _("symbol"); 3617 break; 3618 } 3619 3620 (*_bfd_error_handler) 3621 (_("%B: relocation R_386_GOTOFF against undefined %s `%s' can not be used when making a shared object"), 3622 input_bfd, v, h->root.root.string); 3623 bfd_set_error (bfd_error_bad_value); 3624 return FALSE; 3625 } 3626 else if (!info->executable 3627 && !SYMBOLIC_BIND (info, h) 3628 && h->type == STT_FUNC 3629 && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED) 3630 { 3631 (*_bfd_error_handler) 3632 (_("%B: relocation R_386_GOTOFF against protected function `%s' can not be used when making a shared object"), 3633 input_bfd, h->root.root.string); 3634 bfd_set_error (bfd_error_bad_value); 3635 return FALSE; 3636 } 3637 } 3638 3639 /* Note that sgot is not involved in this 3640 calculation. We always want the start of .got.plt. If we 3641 defined _GLOBAL_OFFSET_TABLE_ in a different way, as is 3642 permitted by the ABI, we might have to change this 3643 calculation. */ 3644 relocation -= htab->elf.sgotplt->output_section->vma 3645 + htab->elf.sgotplt->output_offset; 3646 break; 3647 3648 case R_386_GOTPC: 3649 /* Use global offset table as symbol value. */ 3650 relocation = htab->elf.sgotplt->output_section->vma 3651 + htab->elf.sgotplt->output_offset; 3652 unresolved_reloc = FALSE; 3653 break; 3654 3655 case R_386_PLT32: 3656 /* Relocation is to the entry for this symbol in the 3657 procedure linkage table. */ 3658 3659 /* Resolve a PLT32 reloc against a local symbol directly, 3660 without using the procedure linkage table. */ 3661 if (h == NULL) 3662 break; 3663 3664 if (h->plt.offset == (bfd_vma) -1 3665 || htab->elf.splt == NULL) 3666 { 3667 /* We didn't make a PLT entry for this symbol. This 3668 happens when statically linking PIC code, or when 3669 using -Bsymbolic. */ 3670 break; 3671 } 3672 3673 relocation = (htab->elf.splt->output_section->vma 3674 + htab->elf.splt->output_offset 3675 + h->plt.offset); 3676 unresolved_reloc = FALSE; 3677 break; 3678 3679 case R_386_SIZE32: 3680 /* Set to symbol size. */ 3681 relocation = st_size; 3682 /* Fall through. */ 3683 3684 case R_386_32: 3685 case R_386_PC32: 3686 if ((input_section->flags & SEC_ALLOC) == 0 3687 || is_vxworks_tls) 3688 break; 3689 3690 if ((info->shared 3691 && (h == NULL 3692 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT 3693 || h->root.type != bfd_link_hash_undefweak) 3694 && ((r_type != R_386_PC32 && r_type != R_386_SIZE32) 3695 || !SYMBOL_CALLS_LOCAL (info, h))) 3696 || (ELIMINATE_COPY_RELOCS 3697 && !info->shared 3698 && h != NULL 3699 && h->dynindx != -1 3700 && !h->non_got_ref 3701 && ((h->def_dynamic 3702 && !h->def_regular) 3703 || h->root.type == bfd_link_hash_undefweak 3704 || h->root.type == bfd_link_hash_undefined))) 3705 { 3706 Elf_Internal_Rela outrel; 3707 bfd_boolean skip, relocate; 3708 asection *sreloc; 3709 3710 /* When generating a shared object, these relocations 3711 are copied into the output file to be resolved at run 3712 time. */ 3713 3714 skip = FALSE; 3715 relocate = FALSE; 3716 3717 outrel.r_offset = 3718 _bfd_elf_section_offset (output_bfd, info, input_section, 3719 rel->r_offset); 3720 if (outrel.r_offset == (bfd_vma) -1) 3721 skip = TRUE; 3722 else if (outrel.r_offset == (bfd_vma) -2) 3723 skip = TRUE, relocate = TRUE; 3724 outrel.r_offset += (input_section->output_section->vma 3725 + input_section->output_offset); 3726 3727 if (skip) 3728 memset (&outrel, 0, sizeof outrel); 3729 else if (h != NULL 3730 && h->dynindx != -1 3731 && (r_type == R_386_PC32 3732 || !info->shared 3733 || !SYMBOLIC_BIND (info, h) 3734 || !h->def_regular)) 3735 outrel.r_info = ELF32_R_INFO (h->dynindx, r_type); 3736 else 3737 { 3738 /* This symbol is local, or marked to become local. */ 3739 relocate = TRUE; 3740 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE); 3741 } 3742 3743 sreloc = elf_section_data (input_section)->sreloc; 3744 3745 if (sreloc == NULL || sreloc->contents == NULL) 3746 { 3747 r = bfd_reloc_notsupported; 3748 goto check_relocation_error; 3749 } 3750 3751 elf_append_rel (output_bfd, sreloc, &outrel); 3752 3753 /* If this reloc is against an external symbol, we do 3754 not want to fiddle with the addend. Otherwise, we 3755 need to include the symbol value so that it becomes 3756 an addend for the dynamic reloc. */ 3757 if (! relocate) 3758 continue; 3759 } 3760 break; 3761 3762 case R_386_TLS_IE: 3763 if (!info->executable) 3764 { 3765 Elf_Internal_Rela outrel; 3766 asection *sreloc; 3767 3768 outrel.r_offset = rel->r_offset 3769 + input_section->output_section->vma 3770 + input_section->output_offset; 3771 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE); 3772 sreloc = elf_section_data (input_section)->sreloc; 3773 if (sreloc == NULL) 3774 abort (); 3775 elf_append_rel (output_bfd, sreloc, &outrel); 3776 } 3777 /* Fall through */ 3778 3779 case R_386_TLS_GD: 3780 case R_386_TLS_GOTDESC: 3781 case R_386_TLS_DESC_CALL: 3782 case R_386_TLS_IE_32: 3783 case R_386_TLS_GOTIE: 3784 tls_type = GOT_UNKNOWN; 3785 if (h == NULL && local_got_offsets) 3786 tls_type = elf_i386_local_got_tls_type (input_bfd) [r_symndx]; 3787 else if (h != NULL) 3788 tls_type = elf_i386_hash_entry(h)->tls_type; 3789 if (tls_type == GOT_TLS_IE) 3790 tls_type = GOT_TLS_IE_NEG; 3791 3792 if (! elf_i386_tls_transition (info, input_bfd, 3793 input_section, contents, 3794 symtab_hdr, sym_hashes, 3795 &r_type, tls_type, rel, 3796 relend, h, r_symndx)) 3797 return FALSE; 3798 3799 if (r_type == R_386_TLS_LE_32) 3800 { 3801 BFD_ASSERT (! unresolved_reloc); 3802 if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_GD) 3803 { 3804 unsigned int type; 3805 bfd_vma roff; 3806 3807 /* GD->LE transition. */ 3808 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2); 3809 if (type == 0x04) 3810 { 3811 /* leal foo(,%reg,1), %eax; call ___tls_get_addr 3812 Change it into: 3813 movl %gs:0, %eax; subl $foo@tpoff, %eax 3814 (6 byte form of subl). */ 3815 memcpy (contents + rel->r_offset - 3, 3816 "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12); 3817 roff = rel->r_offset + 5; 3818 } 3819 else 3820 { 3821 /* leal foo(%reg), %eax; call ___tls_get_addr; nop 3822 Change it into: 3823 movl %gs:0, %eax; subl $foo@tpoff, %eax 3824 (6 byte form of subl). */ 3825 memcpy (contents + rel->r_offset - 2, 3826 "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12); 3827 roff = rel->r_offset + 6; 3828 } 3829 bfd_put_32 (output_bfd, elf_i386_tpoff (info, relocation), 3830 contents + roff); 3831 /* Skip R_386_PC32/R_386_PLT32. */ 3832 rel++; 3833 continue; 3834 } 3835 else if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_GOTDESC) 3836 { 3837 /* GDesc -> LE transition. 3838 It's originally something like: 3839 leal x@tlsdesc(%ebx), %eax 3840 3841 leal x@ntpoff, %eax 3842 3843 Registers other than %eax may be set up here. */ 3844 3845 unsigned int val; 3846 bfd_vma roff; 3847 3848 roff = rel->r_offset; 3849 val = bfd_get_8 (input_bfd, contents + roff - 1); 3850 3851 /* Now modify the instruction as appropriate. */ 3852 /* aoliva FIXME: remove the above and xor the byte 3853 below with 0x86. */ 3854 bfd_put_8 (output_bfd, val ^ 0x86, 3855 contents + roff - 1); 3856 bfd_put_32 (output_bfd, -elf_i386_tpoff (info, relocation), 3857 contents + roff); 3858 continue; 3859 } 3860 else if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_DESC_CALL) 3861 { 3862 /* GDesc -> LE transition. 3863 It's originally: 3864 call *(%eax) 3865 Turn it into: 3866 xchg %ax,%ax */ 3867 3868 bfd_vma roff; 3869 3870 roff = rel->r_offset; 3871 bfd_put_8 (output_bfd, 0x66, contents + roff); 3872 bfd_put_8 (output_bfd, 0x90, contents + roff + 1); 3873 continue; 3874 } 3875 else if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_IE) 3876 { 3877 unsigned int val; 3878 3879 /* IE->LE transition: 3880 Originally it can be one of: 3881 movl foo, %eax 3882 movl foo, %reg 3883 addl foo, %reg 3884 We change it into: 3885 movl $foo, %eax 3886 movl $foo, %reg 3887 addl $foo, %reg. */ 3888 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 1); 3889 if (val == 0xa1) 3890 { 3891 /* movl foo, %eax. */ 3892 bfd_put_8 (output_bfd, 0xb8, 3893 contents + rel->r_offset - 1); 3894 } 3895 else 3896 { 3897 unsigned int type; 3898 3899 type = bfd_get_8 (input_bfd, 3900 contents + rel->r_offset - 2); 3901 switch (type) 3902 { 3903 case 0x8b: 3904 /* movl */ 3905 bfd_put_8 (output_bfd, 0xc7, 3906 contents + rel->r_offset - 2); 3907 bfd_put_8 (output_bfd, 3908 0xc0 | ((val >> 3) & 7), 3909 contents + rel->r_offset - 1); 3910 break; 3911 case 0x03: 3912 /* addl */ 3913 bfd_put_8 (output_bfd, 0x81, 3914 contents + rel->r_offset - 2); 3915 bfd_put_8 (output_bfd, 3916 0xc0 | ((val >> 3) & 7), 3917 contents + rel->r_offset - 1); 3918 break; 3919 default: 3920 BFD_FAIL (); 3921 break; 3922 } 3923 } 3924 bfd_put_32 (output_bfd, -elf_i386_tpoff (info, relocation), 3925 contents + rel->r_offset); 3926 continue; 3927 } 3928 else 3929 { 3930 unsigned int val, type; 3931 3932 /* {IE_32,GOTIE}->LE transition: 3933 Originally it can be one of: 3934 subl foo(%reg1), %reg2 3935 movl foo(%reg1), %reg2 3936 addl foo(%reg1), %reg2 3937 We change it into: 3938 subl $foo, %reg2 3939 movl $foo, %reg2 (6 byte form) 3940 addl $foo, %reg2. */ 3941 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2); 3942 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 1); 3943 if (type == 0x8b) 3944 { 3945 /* movl */ 3946 bfd_put_8 (output_bfd, 0xc7, 3947 contents + rel->r_offset - 2); 3948 bfd_put_8 (output_bfd, 0xc0 | ((val >> 3) & 7), 3949 contents + rel->r_offset - 1); 3950 } 3951 else if (type == 0x2b) 3952 { 3953 /* subl */ 3954 bfd_put_8 (output_bfd, 0x81, 3955 contents + rel->r_offset - 2); 3956 bfd_put_8 (output_bfd, 0xe8 | ((val >> 3) & 7), 3957 contents + rel->r_offset - 1); 3958 } 3959 else if (type == 0x03) 3960 { 3961 /* addl */ 3962 bfd_put_8 (output_bfd, 0x81, 3963 contents + rel->r_offset - 2); 3964 bfd_put_8 (output_bfd, 0xc0 | ((val >> 3) & 7), 3965 contents + rel->r_offset - 1); 3966 } 3967 else 3968 BFD_FAIL (); 3969 if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_GOTIE) 3970 bfd_put_32 (output_bfd, -elf_i386_tpoff (info, relocation), 3971 contents + rel->r_offset); 3972 else 3973 bfd_put_32 (output_bfd, elf_i386_tpoff (info, relocation), 3974 contents + rel->r_offset); 3975 continue; 3976 } 3977 } 3978 3979 if (htab->elf.sgot == NULL) 3980 abort (); 3981 3982 if (h != NULL) 3983 { 3984 off = h->got.offset; 3985 offplt = elf_i386_hash_entry (h)->tlsdesc_got; 3986 } 3987 else 3988 { 3989 if (local_got_offsets == NULL) 3990 abort (); 3991 3992 off = local_got_offsets[r_symndx]; 3993 offplt = local_tlsdesc_gotents[r_symndx]; 3994 } 3995 3996 if ((off & 1) != 0) 3997 off &= ~1; 3998 else 3999 { 4000 Elf_Internal_Rela outrel; 4001 int dr_type; 4002 asection *sreloc; 4003 4004 if (htab->elf.srelgot == NULL) 4005 abort (); 4006 4007 indx = h && h->dynindx != -1 ? h->dynindx : 0; 4008 4009 if (GOT_TLS_GDESC_P (tls_type)) 4010 { 4011 bfd_byte *loc; 4012 outrel.r_info = ELF32_R_INFO (indx, R_386_TLS_DESC); 4013 BFD_ASSERT (htab->sgotplt_jump_table_size + offplt + 8 4014 <= htab->elf.sgotplt->size); 4015 outrel.r_offset = (htab->elf.sgotplt->output_section->vma 4016 + htab->elf.sgotplt->output_offset 4017 + offplt 4018 + htab->sgotplt_jump_table_size); 4019 sreloc = htab->elf.srelplt; 4020 loc = sreloc->contents; 4021 loc += (htab->next_tls_desc_index++ 4022 * sizeof (Elf32_External_Rel)); 4023 BFD_ASSERT (loc + sizeof (Elf32_External_Rel) 4024 <= sreloc->contents + sreloc->size); 4025 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc); 4026 if (indx == 0) 4027 { 4028 BFD_ASSERT (! unresolved_reloc); 4029 bfd_put_32 (output_bfd, 4030 relocation - elf_i386_dtpoff_base (info), 4031 htab->elf.sgotplt->contents + offplt 4032 + htab->sgotplt_jump_table_size + 4); 4033 } 4034 else 4035 { 4036 bfd_put_32 (output_bfd, 0, 4037 htab->elf.sgotplt->contents + offplt 4038 + htab->sgotplt_jump_table_size + 4); 4039 } 4040 } 4041 4042 sreloc = htab->elf.srelgot; 4043 4044 outrel.r_offset = (htab->elf.sgot->output_section->vma 4045 + htab->elf.sgot->output_offset + off); 4046 4047 if (GOT_TLS_GD_P (tls_type)) 4048 dr_type = R_386_TLS_DTPMOD32; 4049 else if (GOT_TLS_GDESC_P (tls_type)) 4050 goto dr_done; 4051 else if (tls_type == GOT_TLS_IE_POS) 4052 dr_type = R_386_TLS_TPOFF; 4053 else 4054 dr_type = R_386_TLS_TPOFF32; 4055 4056 if (dr_type == R_386_TLS_TPOFF && indx == 0) 4057 bfd_put_32 (output_bfd, 4058 relocation - elf_i386_dtpoff_base (info), 4059 htab->elf.sgot->contents + off); 4060 else if (dr_type == R_386_TLS_TPOFF32 && indx == 0) 4061 bfd_put_32 (output_bfd, 4062 elf_i386_dtpoff_base (info) - relocation, 4063 htab->elf.sgot->contents + off); 4064 else if (dr_type != R_386_TLS_DESC) 4065 bfd_put_32 (output_bfd, 0, 4066 htab->elf.sgot->contents + off); 4067 outrel.r_info = ELF32_R_INFO (indx, dr_type); 4068 4069 elf_append_rel (output_bfd, sreloc, &outrel); 4070 4071 if (GOT_TLS_GD_P (tls_type)) 4072 { 4073 if (indx == 0) 4074 { 4075 BFD_ASSERT (! unresolved_reloc); 4076 bfd_put_32 (output_bfd, 4077 relocation - elf_i386_dtpoff_base (info), 4078 htab->elf.sgot->contents + off + 4); 4079 } 4080 else 4081 { 4082 bfd_put_32 (output_bfd, 0, 4083 htab->elf.sgot->contents + off + 4); 4084 outrel.r_info = ELF32_R_INFO (indx, 4085 R_386_TLS_DTPOFF32); 4086 outrel.r_offset += 4; 4087 elf_append_rel (output_bfd, sreloc, &outrel); 4088 } 4089 } 4090 else if (tls_type == GOT_TLS_IE_BOTH) 4091 { 4092 bfd_put_32 (output_bfd, 4093 (indx == 0 4094 ? relocation - elf_i386_dtpoff_base (info) 4095 : 0), 4096 htab->elf.sgot->contents + off + 4); 4097 outrel.r_info = ELF32_R_INFO (indx, R_386_TLS_TPOFF); 4098 outrel.r_offset += 4; 4099 elf_append_rel (output_bfd, sreloc, &outrel); 4100 } 4101 4102 dr_done: 4103 if (h != NULL) 4104 h->got.offset |= 1; 4105 else 4106 local_got_offsets[r_symndx] |= 1; 4107 } 4108 4109 if (off >= (bfd_vma) -2 4110 && ! GOT_TLS_GDESC_P (tls_type)) 4111 abort (); 4112 if (r_type == R_386_TLS_GOTDESC 4113 || r_type == R_386_TLS_DESC_CALL) 4114 { 4115 relocation = htab->sgotplt_jump_table_size + offplt; 4116 unresolved_reloc = FALSE; 4117 } 4118 else if (r_type == ELF32_R_TYPE (rel->r_info)) 4119 { 4120 bfd_vma g_o_t = htab->elf.sgotplt->output_section->vma 4121 + htab->elf.sgotplt->output_offset; 4122 relocation = htab->elf.sgot->output_section->vma 4123 + htab->elf.sgot->output_offset + off - g_o_t; 4124 if ((r_type == R_386_TLS_IE || r_type == R_386_TLS_GOTIE) 4125 && tls_type == GOT_TLS_IE_BOTH) 4126 relocation += 4; 4127 if (r_type == R_386_TLS_IE) 4128 relocation += g_o_t; 4129 unresolved_reloc = FALSE; 4130 } 4131 else if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_GD) 4132 { 4133 unsigned int val, type; 4134 bfd_vma roff; 4135 4136 /* GD->IE transition. */ 4137 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2); 4138 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 1); 4139 if (type == 0x04) 4140 { 4141 /* leal foo(,%reg,1), %eax; call ___tls_get_addr 4142 Change it into: 4143 movl %gs:0, %eax; subl $foo@gottpoff(%reg), %eax. */ 4144 val >>= 3; 4145 roff = rel->r_offset - 3; 4146 } 4147 else 4148 { 4149 /* leal foo(%reg), %eax; call ___tls_get_addr; nop 4150 Change it into: 4151 movl %gs:0, %eax; subl $foo@gottpoff(%reg), %eax. */ 4152 roff = rel->r_offset - 2; 4153 } 4154 memcpy (contents + roff, 4155 "\x65\xa1\0\0\0\0\x2b\x80\0\0\0", 12); 4156 contents[roff + 7] = 0x80 | (val & 7); 4157 /* If foo is used only with foo@gotntpoff(%reg) and 4158 foo@indntpoff, but not with foo@gottpoff(%reg), change 4159 subl $foo@gottpoff(%reg), %eax 4160 into: 4161 addl $foo@gotntpoff(%reg), %eax. */ 4162 if (tls_type == GOT_TLS_IE_POS) 4163 contents[roff + 6] = 0x03; 4164 bfd_put_32 (output_bfd, 4165 htab->elf.sgot->output_section->vma 4166 + htab->elf.sgot->output_offset + off 4167 - htab->elf.sgotplt->output_section->vma 4168 - htab->elf.sgotplt->output_offset, 4169 contents + roff + 8); 4170 /* Skip R_386_PLT32. */ 4171 rel++; 4172 continue; 4173 } 4174 else if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_GOTDESC) 4175 { 4176 /* GDesc -> IE transition. 4177 It's originally something like: 4178 leal x@tlsdesc(%ebx), %eax 4179 4180 Change it to: 4181 movl x@gotntpoff(%ebx), %eax # before xchg %ax,%ax 4182 or: 4183 movl x@gottpoff(%ebx), %eax # before negl %eax 4184 4185 Registers other than %eax may be set up here. */ 4186 4187 bfd_vma roff; 4188 4189 /* First, make sure it's a leal adding ebx to a 32-bit 4190 offset into any register, although it's probably 4191 almost always going to be eax. */ 4192 roff = rel->r_offset; 4193 4194 /* Now modify the instruction as appropriate. */ 4195 /* To turn a leal into a movl in the form we use it, it 4196 suffices to change the first byte from 0x8d to 0x8b. 4197 aoliva FIXME: should we decide to keep the leal, all 4198 we have to do is remove the statement below, and 4199 adjust the relaxation of R_386_TLS_DESC_CALL. */ 4200 bfd_put_8 (output_bfd, 0x8b, contents + roff - 2); 4201 4202 if (tls_type == GOT_TLS_IE_BOTH) 4203 off += 4; 4204 4205 bfd_put_32 (output_bfd, 4206 htab->elf.sgot->output_section->vma 4207 + htab->elf.sgot->output_offset + off 4208 - htab->elf.sgotplt->output_section->vma 4209 - htab->elf.sgotplt->output_offset, 4210 contents + roff); 4211 continue; 4212 } 4213 else if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_DESC_CALL) 4214 { 4215 /* GDesc -> IE transition. 4216 It's originally: 4217 call *(%eax) 4218 4219 Change it to: 4220 xchg %ax,%ax 4221 or 4222 negl %eax 4223 depending on how we transformed the TLS_GOTDESC above. 4224 */ 4225 4226 bfd_vma roff; 4227 4228 roff = rel->r_offset; 4229 4230 /* Now modify the instruction as appropriate. */ 4231 if (tls_type != GOT_TLS_IE_NEG) 4232 { 4233 /* xchg %ax,%ax */ 4234 bfd_put_8 (output_bfd, 0x66, contents + roff); 4235 bfd_put_8 (output_bfd, 0x90, contents + roff + 1); 4236 } 4237 else 4238 { 4239 /* negl %eax */ 4240 bfd_put_8 (output_bfd, 0xf7, contents + roff); 4241 bfd_put_8 (output_bfd, 0xd8, contents + roff + 1); 4242 } 4243 4244 continue; 4245 } 4246 else 4247 BFD_ASSERT (FALSE); 4248 break; 4249 4250 case R_386_TLS_LDM: 4251 if (! elf_i386_tls_transition (info, input_bfd, 4252 input_section, contents, 4253 symtab_hdr, sym_hashes, 4254 &r_type, GOT_UNKNOWN, rel, 4255 relend, h, r_symndx)) 4256 return FALSE; 4257 4258 if (r_type != R_386_TLS_LDM) 4259 { 4260 /* LD->LE transition: 4261 leal foo(%reg), %eax; call ___tls_get_addr. 4262 We change it into: 4263 movl %gs:0, %eax; nop; leal 0(%esi,1), %esi. */ 4264 BFD_ASSERT (r_type == R_386_TLS_LE_32); 4265 memcpy (contents + rel->r_offset - 2, 4266 "\x65\xa1\0\0\0\0\x90\x8d\x74\x26", 11); 4267 /* Skip R_386_PC32/R_386_PLT32. */ 4268 rel++; 4269 continue; 4270 } 4271 4272 if (htab->elf.sgot == NULL) 4273 abort (); 4274 4275 off = htab->tls_ldm_got.offset; 4276 if (off & 1) 4277 off &= ~1; 4278 else 4279 { 4280 Elf_Internal_Rela outrel; 4281 4282 if (htab->elf.srelgot == NULL) 4283 abort (); 4284 4285 outrel.r_offset = (htab->elf.sgot->output_section->vma 4286 + htab->elf.sgot->output_offset + off); 4287 4288 bfd_put_32 (output_bfd, 0, 4289 htab->elf.sgot->contents + off); 4290 bfd_put_32 (output_bfd, 0, 4291 htab->elf.sgot->contents + off + 4); 4292 outrel.r_info = ELF32_R_INFO (0, R_386_TLS_DTPMOD32); 4293 elf_append_rel (output_bfd, htab->elf.srelgot, &outrel); 4294 htab->tls_ldm_got.offset |= 1; 4295 } 4296 relocation = htab->elf.sgot->output_section->vma 4297 + htab->elf.sgot->output_offset + off 4298 - htab->elf.sgotplt->output_section->vma 4299 - htab->elf.sgotplt->output_offset; 4300 unresolved_reloc = FALSE; 4301 break; 4302 4303 case R_386_TLS_LDO_32: 4304 if (!info->executable || (input_section->flags & SEC_CODE) == 0) 4305 relocation -= elf_i386_dtpoff_base (info); 4306 else 4307 /* When converting LDO to LE, we must negate. */ 4308 relocation = -elf_i386_tpoff (info, relocation); 4309 break; 4310 4311 case R_386_TLS_LE_32: 4312 case R_386_TLS_LE: 4313 if (!info->executable) 4314 { 4315 Elf_Internal_Rela outrel; 4316 asection *sreloc; 4317 4318 outrel.r_offset = rel->r_offset 4319 + input_section->output_section->vma 4320 + input_section->output_offset; 4321 if (h != NULL && h->dynindx != -1) 4322 indx = h->dynindx; 4323 else 4324 indx = 0; 4325 if (r_type == R_386_TLS_LE_32) 4326 outrel.r_info = ELF32_R_INFO (indx, R_386_TLS_TPOFF32); 4327 else 4328 outrel.r_info = ELF32_R_INFO (indx, R_386_TLS_TPOFF); 4329 sreloc = elf_section_data (input_section)->sreloc; 4330 if (sreloc == NULL) 4331 abort (); 4332 elf_append_rel (output_bfd, sreloc, &outrel); 4333 if (indx) 4334 continue; 4335 else if (r_type == R_386_TLS_LE_32) 4336 relocation = elf_i386_dtpoff_base (info) - relocation; 4337 else 4338 relocation -= elf_i386_dtpoff_base (info); 4339 } 4340 else if (r_type == R_386_TLS_LE_32) 4341 relocation = elf_i386_tpoff (info, relocation); 4342 else 4343 relocation = -elf_i386_tpoff (info, relocation); 4344 break; 4345 4346 default: 4347 break; 4348 } 4349 4350 /* Dynamic relocs are not propagated for SEC_DEBUGGING sections 4351 because such sections are not SEC_ALLOC and thus ld.so will 4352 not process them. */ 4353 if (unresolved_reloc 4354 && !((input_section->flags & SEC_DEBUGGING) != 0 4355 && h->def_dynamic) 4356 && _bfd_elf_section_offset (output_bfd, info, input_section, 4357 rel->r_offset) != (bfd_vma) -1) 4358 { 4359 (*_bfd_error_handler) 4360 (_("%B(%A+0x%lx): unresolvable %s relocation against symbol `%s'"), 4361 input_bfd, 4362 input_section, 4363 (long) rel->r_offset, 4364 howto->name, 4365 h->root.root.string); 4366 return FALSE; 4367 } 4368 4369 do_relocation: 4370 r = _bfd_final_link_relocate (howto, input_bfd, input_section, 4371 contents, rel->r_offset, 4372 relocation, 0); 4373 4374 check_relocation_error: 4375 if (r != bfd_reloc_ok) 4376 { 4377 const char *name; 4378 4379 if (h != NULL) 4380 name = h->root.root.string; 4381 else 4382 { 4383 name = bfd_elf_string_from_elf_section (input_bfd, 4384 symtab_hdr->sh_link, 4385 sym->st_name); 4386 if (name == NULL) 4387 return FALSE; 4388 if (*name == '\0') 4389 name = bfd_section_name (input_bfd, sec); 4390 } 4391 4392 if (r == bfd_reloc_overflow) 4393 { 4394 if (! ((*info->callbacks->reloc_overflow) 4395 (info, (h ? &h->root : NULL), name, howto->name, 4396 (bfd_vma) 0, input_bfd, input_section, 4397 rel->r_offset))) 4398 return FALSE; 4399 } 4400 else 4401 { 4402 (*_bfd_error_handler) 4403 (_("%B(%A+0x%lx): reloc against `%s': error %d"), 4404 input_bfd, input_section, 4405 (long) rel->r_offset, name, (int) r); 4406 return FALSE; 4407 } 4408 } 4409 } 4410 4411 return TRUE; 4412 } 4413 4414 /* Finish up dynamic symbol handling. We set the contents of various 4415 dynamic sections here. */ 4416 4417 static bfd_boolean 4418 elf_i386_finish_dynamic_symbol (bfd *output_bfd, 4419 struct bfd_link_info *info, 4420 struct elf_link_hash_entry *h, 4421 Elf_Internal_Sym *sym) 4422 { 4423 struct elf_i386_link_hash_table *htab; 4424 unsigned plt_entry_size; 4425 const struct elf_i386_backend_data *abed; 4426 4427 htab = elf_i386_hash_table (info); 4428 if (htab == NULL) 4429 return FALSE; 4430 4431 abed = get_elf_i386_backend_data (output_bfd); 4432 plt_entry_size = GET_PLT_ENTRY_SIZE (output_bfd); 4433 4434 if (h->plt.offset != (bfd_vma) -1) 4435 { 4436 bfd_vma plt_index; 4437 bfd_vma got_offset; 4438 Elf_Internal_Rela rel; 4439 bfd_byte *loc; 4440 asection *plt, *gotplt, *relplt; 4441 4442 /* When building a static executable, use .iplt, .igot.plt and 4443 .rel.iplt sections for STT_GNU_IFUNC symbols. */ 4444 if (htab->elf.splt != NULL) 4445 { 4446 plt = htab->elf.splt; 4447 gotplt = htab->elf.sgotplt; 4448 relplt = htab->elf.srelplt; 4449 } 4450 else 4451 { 4452 plt = htab->elf.iplt; 4453 gotplt = htab->elf.igotplt; 4454 relplt = htab->elf.irelplt; 4455 } 4456 4457 /* This symbol has an entry in the procedure linkage table. Set 4458 it up. */ 4459 4460 if ((h->dynindx == -1 4461 && !((h->forced_local || info->executable) 4462 && h->def_regular 4463 && h->type == STT_GNU_IFUNC)) 4464 || plt == NULL 4465 || gotplt == NULL 4466 || relplt == NULL) 4467 abort (); 4468 4469 /* Get the index in the procedure linkage table which 4470 corresponds to this symbol. This is the index of this symbol 4471 in all the symbols for which we are making plt entries. The 4472 first entry in the procedure linkage table is reserved. 4473 4474 Get the offset into the .got table of the entry that 4475 corresponds to this function. Each .got entry is 4 bytes. 4476 The first three are reserved. 4477 4478 For static executables, we don't reserve anything. */ 4479 4480 if (plt == htab->elf.splt) 4481 { 4482 got_offset = h->plt.offset / plt_entry_size - 1; 4483 got_offset = (got_offset + 3) * 4; 4484 } 4485 else 4486 { 4487 got_offset = h->plt.offset / plt_entry_size; 4488 got_offset = got_offset * 4; 4489 } 4490 4491 /* Fill in the entry in the procedure linkage table. */ 4492 if (! info->shared) 4493 { 4494 memcpy (plt->contents + h->plt.offset, abed->plt->plt_entry, 4495 abed->plt->plt_entry_size); 4496 bfd_put_32 (output_bfd, 4497 (gotplt->output_section->vma 4498 + gotplt->output_offset 4499 + got_offset), 4500 plt->contents + h->plt.offset 4501 + abed->plt->plt_got_offset); 4502 4503 if (abed->is_vxworks) 4504 { 4505 int s, k, reloc_index; 4506 4507 /* Create the R_386_32 relocation referencing the GOT 4508 for this PLT entry. */ 4509 4510 /* S: Current slot number (zero-based). */ 4511 s = ((h->plt.offset - abed->plt->plt_entry_size) 4512 / abed->plt->plt_entry_size); 4513 /* K: Number of relocations for PLTResolve. */ 4514 if (info->shared) 4515 k = PLTRESOLVE_RELOCS_SHLIB; 4516 else 4517 k = PLTRESOLVE_RELOCS; 4518 /* Skip the PLTresolve relocations, and the relocations for 4519 the other PLT slots. */ 4520 reloc_index = k + s * PLT_NON_JUMP_SLOT_RELOCS; 4521 loc = (htab->srelplt2->contents + reloc_index 4522 * sizeof (Elf32_External_Rel)); 4523 4524 rel.r_offset = (htab->elf.splt->output_section->vma 4525 + htab->elf.splt->output_offset 4526 + h->plt.offset + 2), 4527 rel.r_info = ELF32_R_INFO (htab->elf.hgot->indx, R_386_32); 4528 bfd_elf32_swap_reloc_out (output_bfd, &rel, loc); 4529 4530 /* Create the R_386_32 relocation referencing the beginning of 4531 the PLT for this GOT entry. */ 4532 rel.r_offset = (htab->elf.sgotplt->output_section->vma 4533 + htab->elf.sgotplt->output_offset 4534 + got_offset); 4535 rel.r_info = ELF32_R_INFO (htab->elf.hplt->indx, R_386_32); 4536 bfd_elf32_swap_reloc_out (output_bfd, &rel, 4537 loc + sizeof (Elf32_External_Rel)); 4538 } 4539 } 4540 else 4541 { 4542 memcpy (plt->contents + h->plt.offset, abed->plt->pic_plt_entry, 4543 abed->plt->plt_entry_size); 4544 bfd_put_32 (output_bfd, got_offset, 4545 plt->contents + h->plt.offset 4546 + abed->plt->plt_got_offset); 4547 } 4548 4549 /* Fill in the entry in the global offset table. */ 4550 bfd_put_32 (output_bfd, 4551 (plt->output_section->vma 4552 + plt->output_offset 4553 + h->plt.offset 4554 + abed->plt->plt_lazy_offset), 4555 gotplt->contents + got_offset); 4556 4557 /* Fill in the entry in the .rel.plt section. */ 4558 rel.r_offset = (gotplt->output_section->vma 4559 + gotplt->output_offset 4560 + got_offset); 4561 if (h->dynindx == -1 4562 || ((info->executable 4563 || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT) 4564 && h->def_regular 4565 && h->type == STT_GNU_IFUNC)) 4566 { 4567 /* If an STT_GNU_IFUNC symbol is locally defined, generate 4568 R_386_IRELATIVE instead of R_386_JUMP_SLOT. Store addend 4569 in the .got.plt section. */ 4570 bfd_put_32 (output_bfd, 4571 (h->root.u.def.value 4572 + h->root.u.def.section->output_section->vma 4573 + h->root.u.def.section->output_offset), 4574 gotplt->contents + got_offset); 4575 rel.r_info = ELF32_R_INFO (0, R_386_IRELATIVE); 4576 /* R_386_IRELATIVE comes last. */ 4577 plt_index = htab->next_irelative_index--; 4578 } 4579 else 4580 { 4581 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_JUMP_SLOT); 4582 plt_index = htab->next_jump_slot_index++; 4583 } 4584 loc = relplt->contents + plt_index * sizeof (Elf32_External_Rel); 4585 bfd_elf32_swap_reloc_out (output_bfd, &rel, loc); 4586 4587 /* Don't fill PLT entry for static executables. */ 4588 if (plt == htab->elf.splt) 4589 { 4590 bfd_put_32 (output_bfd, plt_index * sizeof (Elf32_External_Rel), 4591 plt->contents + h->plt.offset 4592 + abed->plt->plt_reloc_offset); 4593 bfd_put_32 (output_bfd, - (h->plt.offset 4594 + abed->plt->plt_plt_offset + 4), 4595 plt->contents + h->plt.offset 4596 + abed->plt->plt_plt_offset); 4597 } 4598 4599 if (!h->def_regular) 4600 { 4601 /* Mark the symbol as undefined, rather than as defined in 4602 the .plt section. Leave the value if there were any 4603 relocations where pointer equality matters (this is a clue 4604 for the dynamic linker, to make function pointer 4605 comparisons work between an application and shared 4606 library), otherwise set it to zero. If a function is only 4607 called from a binary, there is no need to slow down 4608 shared libraries because of that. */ 4609 sym->st_shndx = SHN_UNDEF; 4610 if (!h->pointer_equality_needed) 4611 sym->st_value = 0; 4612 } 4613 } 4614 4615 if (h->got.offset != (bfd_vma) -1 4616 && ! GOT_TLS_GD_ANY_P (elf_i386_hash_entry(h)->tls_type) 4617 && (elf_i386_hash_entry(h)->tls_type & GOT_TLS_IE) == 0) 4618 { 4619 Elf_Internal_Rela rel; 4620 4621 /* This symbol has an entry in the global offset table. Set it 4622 up. */ 4623 4624 if (htab->elf.sgot == NULL || htab->elf.srelgot == NULL) 4625 abort (); 4626 4627 rel.r_offset = (htab->elf.sgot->output_section->vma 4628 + htab->elf.sgot->output_offset 4629 + (h->got.offset & ~(bfd_vma) 1)); 4630 4631 /* If this is a static link, or it is a -Bsymbolic link and the 4632 symbol is defined locally or was forced to be local because 4633 of a version file, we just want to emit a RELATIVE reloc. 4634 The entry in the global offset table will already have been 4635 initialized in the relocate_section function. */ 4636 if (h->def_regular 4637 && h->type == STT_GNU_IFUNC) 4638 { 4639 if (info->shared) 4640 { 4641 /* Generate R_386_GLOB_DAT. */ 4642 goto do_glob_dat; 4643 } 4644 else 4645 { 4646 asection *plt; 4647 4648 if (!h->pointer_equality_needed) 4649 abort (); 4650 4651 /* For non-shared object, we can't use .got.plt, which 4652 contains the real function addres if we need pointer 4653 equality. We load the GOT entry with the PLT entry. */ 4654 plt = htab->elf.splt ? htab->elf.splt : htab->elf.iplt; 4655 bfd_put_32 (output_bfd, 4656 (plt->output_section->vma 4657 + plt->output_offset + h->plt.offset), 4658 htab->elf.sgot->contents + h->got.offset); 4659 return TRUE; 4660 } 4661 } 4662 else if (info->shared 4663 && SYMBOL_REFERENCES_LOCAL (info, h)) 4664 { 4665 BFD_ASSERT((h->got.offset & 1) != 0); 4666 rel.r_info = ELF32_R_INFO (0, R_386_RELATIVE); 4667 } 4668 else 4669 { 4670 BFD_ASSERT((h->got.offset & 1) == 0); 4671 do_glob_dat: 4672 bfd_put_32 (output_bfd, (bfd_vma) 0, 4673 htab->elf.sgot->contents + h->got.offset); 4674 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_GLOB_DAT); 4675 } 4676 4677 elf_append_rel (output_bfd, htab->elf.srelgot, &rel); 4678 } 4679 4680 if (h->needs_copy) 4681 { 4682 Elf_Internal_Rela rel; 4683 4684 /* This symbol needs a copy reloc. Set it up. */ 4685 4686 if (h->dynindx == -1 4687 || (h->root.type != bfd_link_hash_defined 4688 && h->root.type != bfd_link_hash_defweak) 4689 || htab->srelbss == NULL) 4690 abort (); 4691 4692 rel.r_offset = (h->root.u.def.value 4693 + h->root.u.def.section->output_section->vma 4694 + h->root.u.def.section->output_offset); 4695 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_COPY); 4696 elf_append_rel (output_bfd, htab->srelbss, &rel); 4697 } 4698 4699 return TRUE; 4700 } 4701 4702 /* Finish up local dynamic symbol handling. We set the contents of 4703 various dynamic sections here. */ 4704 4705 static bfd_boolean 4706 elf_i386_finish_local_dynamic_symbol (void **slot, void *inf) 4707 { 4708 struct elf_link_hash_entry *h 4709 = (struct elf_link_hash_entry *) *slot; 4710 struct bfd_link_info *info 4711 = (struct bfd_link_info *) inf; 4712 4713 return elf_i386_finish_dynamic_symbol (info->output_bfd, info, 4714 h, NULL); 4715 } 4716 4717 /* Used to decide how to sort relocs in an optimal manner for the 4718 dynamic linker, before writing them out. */ 4719 4720 static enum elf_reloc_type_class 4721 elf_i386_reloc_type_class (const Elf_Internal_Rela *rela) 4722 { 4723 switch (ELF32_R_TYPE (rela->r_info)) 4724 { 4725 case R_386_RELATIVE: 4726 return reloc_class_relative; 4727 case R_386_JUMP_SLOT: 4728 return reloc_class_plt; 4729 case R_386_COPY: 4730 return reloc_class_copy; 4731 default: 4732 return reloc_class_normal; 4733 } 4734 } 4735 4736 /* Finish up the dynamic sections. */ 4737 4738 static bfd_boolean 4739 elf_i386_finish_dynamic_sections (bfd *output_bfd, 4740 struct bfd_link_info *info) 4741 { 4742 struct elf_i386_link_hash_table *htab; 4743 bfd *dynobj; 4744 asection *sdyn; 4745 const struct elf_i386_backend_data *abed; 4746 4747 htab = elf_i386_hash_table (info); 4748 if (htab == NULL) 4749 return FALSE; 4750 4751 dynobj = htab->elf.dynobj; 4752 sdyn = bfd_get_linker_section (dynobj, ".dynamic"); 4753 abed = get_elf_i386_backend_data (output_bfd); 4754 4755 if (htab->elf.dynamic_sections_created) 4756 { 4757 Elf32_External_Dyn *dyncon, *dynconend; 4758 4759 if (sdyn == NULL || htab->elf.sgot == NULL) 4760 abort (); 4761 4762 dyncon = (Elf32_External_Dyn *) sdyn->contents; 4763 dynconend = (Elf32_External_Dyn *) (sdyn->contents + sdyn->size); 4764 for (; dyncon < dynconend; dyncon++) 4765 { 4766 Elf_Internal_Dyn dyn; 4767 asection *s; 4768 4769 bfd_elf32_swap_dyn_in (dynobj, dyncon, &dyn); 4770 4771 switch (dyn.d_tag) 4772 { 4773 default: 4774 if (abed->is_vxworks 4775 && elf_vxworks_finish_dynamic_entry (output_bfd, &dyn)) 4776 break; 4777 continue; 4778 4779 case DT_PLTGOT: 4780 s = htab->elf.sgotplt; 4781 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset; 4782 break; 4783 4784 case DT_JMPREL: 4785 s = htab->elf.srelplt; 4786 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset; 4787 break; 4788 4789 case DT_PLTRELSZ: 4790 s = htab->elf.srelplt; 4791 dyn.d_un.d_val = s->size; 4792 break; 4793 4794 case DT_RELSZ: 4795 /* My reading of the SVR4 ABI indicates that the 4796 procedure linkage table relocs (DT_JMPREL) should be 4797 included in the overall relocs (DT_REL). This is 4798 what Solaris does. However, UnixWare can not handle 4799 that case. Therefore, we override the DT_RELSZ entry 4800 here to make it not include the JMPREL relocs. */ 4801 s = htab->elf.srelplt; 4802 if (s == NULL) 4803 continue; 4804 dyn.d_un.d_val -= s->size; 4805 break; 4806 4807 case DT_REL: 4808 /* We may not be using the standard ELF linker script. 4809 If .rel.plt is the first .rel section, we adjust 4810 DT_REL to not include it. */ 4811 s = htab->elf.srelplt; 4812 if (s == NULL) 4813 continue; 4814 if (dyn.d_un.d_ptr != s->output_section->vma + s->output_offset) 4815 continue; 4816 dyn.d_un.d_ptr += s->size; 4817 break; 4818 } 4819 4820 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon); 4821 } 4822 4823 /* Fill in the first entry in the procedure linkage table. */ 4824 if (htab->elf.splt && htab->elf.splt->size > 0) 4825 { 4826 if (info->shared) 4827 { 4828 memcpy (htab->elf.splt->contents, abed->plt->pic_plt0_entry, 4829 abed->plt->plt0_entry_size); 4830 memset (htab->elf.splt->contents + abed->plt->plt0_entry_size, 4831 abed->plt0_pad_byte, 4832 abed->plt->plt_entry_size - abed->plt->plt0_entry_size); 4833 } 4834 else 4835 { 4836 memcpy (htab->elf.splt->contents, abed->plt->plt0_entry, 4837 abed->plt->plt0_entry_size); 4838 memset (htab->elf.splt->contents + abed->plt->plt0_entry_size, 4839 abed->plt0_pad_byte, 4840 abed->plt->plt_entry_size - abed->plt->plt0_entry_size); 4841 bfd_put_32 (output_bfd, 4842 (htab->elf.sgotplt->output_section->vma 4843 + htab->elf.sgotplt->output_offset 4844 + 4), 4845 htab->elf.splt->contents 4846 + abed->plt->plt0_got1_offset); 4847 bfd_put_32 (output_bfd, 4848 (htab->elf.sgotplt->output_section->vma 4849 + htab->elf.sgotplt->output_offset 4850 + 8), 4851 htab->elf.splt->contents 4852 + abed->plt->plt0_got2_offset); 4853 4854 if (abed->is_vxworks) 4855 { 4856 Elf_Internal_Rela rel; 4857 4858 /* Generate a relocation for _GLOBAL_OFFSET_TABLE_ + 4. 4859 On IA32 we use REL relocations so the addend goes in 4860 the PLT directly. */ 4861 rel.r_offset = (htab->elf.splt->output_section->vma 4862 + htab->elf.splt->output_offset 4863 + abed->plt->plt0_got1_offset); 4864 rel.r_info = ELF32_R_INFO (htab->elf.hgot->indx, R_386_32); 4865 bfd_elf32_swap_reloc_out (output_bfd, &rel, 4866 htab->srelplt2->contents); 4867 /* Generate a relocation for _GLOBAL_OFFSET_TABLE_ + 8. */ 4868 rel.r_offset = (htab->elf.splt->output_section->vma 4869 + htab->elf.splt->output_offset 4870 + abed->plt->plt0_got2_offset); 4871 rel.r_info = ELF32_R_INFO (htab->elf.hgot->indx, R_386_32); 4872 bfd_elf32_swap_reloc_out (output_bfd, &rel, 4873 htab->srelplt2->contents + 4874 sizeof (Elf32_External_Rel)); 4875 } 4876 } 4877 4878 /* UnixWare sets the entsize of .plt to 4, although that doesn't 4879 really seem like the right value. */ 4880 elf_section_data (htab->elf.splt->output_section) 4881 ->this_hdr.sh_entsize = 4; 4882 4883 /* Correct the .rel.plt.unloaded relocations. */ 4884 if (abed->is_vxworks && !info->shared) 4885 { 4886 int num_plts = (htab->elf.splt->size 4887 / abed->plt->plt_entry_size) - 1; 4888 unsigned char *p; 4889 4890 p = htab->srelplt2->contents; 4891 if (info->shared) 4892 p += PLTRESOLVE_RELOCS_SHLIB * sizeof (Elf32_External_Rel); 4893 else 4894 p += PLTRESOLVE_RELOCS * sizeof (Elf32_External_Rel); 4895 4896 for (; num_plts; num_plts--) 4897 { 4898 Elf_Internal_Rela rel; 4899 bfd_elf32_swap_reloc_in (output_bfd, p, &rel); 4900 rel.r_info = ELF32_R_INFO (htab->elf.hgot->indx, R_386_32); 4901 bfd_elf32_swap_reloc_out (output_bfd, &rel, p); 4902 p += sizeof (Elf32_External_Rel); 4903 4904 bfd_elf32_swap_reloc_in (output_bfd, p, &rel); 4905 rel.r_info = ELF32_R_INFO (htab->elf.hplt->indx, R_386_32); 4906 bfd_elf32_swap_reloc_out (output_bfd, &rel, p); 4907 p += sizeof (Elf32_External_Rel); 4908 } 4909 } 4910 } 4911 } 4912 4913 if (htab->elf.sgotplt) 4914 { 4915 if (bfd_is_abs_section (htab->elf.sgotplt->output_section)) 4916 { 4917 (*_bfd_error_handler) 4918 (_("discarded output section: `%A'"), htab->elf.sgotplt); 4919 return FALSE; 4920 } 4921 4922 /* Fill in the first three entries in the global offset table. */ 4923 if (htab->elf.sgotplt->size > 0) 4924 { 4925 bfd_put_32 (output_bfd, 4926 (sdyn == NULL ? 0 4927 : sdyn->output_section->vma + sdyn->output_offset), 4928 htab->elf.sgotplt->contents); 4929 bfd_put_32 (output_bfd, 0, htab->elf.sgotplt->contents + 4); 4930 bfd_put_32 (output_bfd, 0, htab->elf.sgotplt->contents + 8); 4931 } 4932 4933 elf_section_data (htab->elf.sgotplt->output_section)->this_hdr.sh_entsize = 4; 4934 } 4935 4936 /* Adjust .eh_frame for .plt section. */ 4937 if (htab->plt_eh_frame != NULL 4938 && htab->plt_eh_frame->contents != NULL) 4939 { 4940 if (htab->elf.splt != NULL 4941 && htab->elf.splt->size != 0 4942 && (htab->elf.splt->flags & SEC_EXCLUDE) == 0 4943 && htab->elf.splt->output_section != NULL 4944 && htab->plt_eh_frame->output_section != NULL) 4945 { 4946 bfd_vma plt_start = htab->elf.splt->output_section->vma; 4947 bfd_vma eh_frame_start = htab->plt_eh_frame->output_section->vma 4948 + htab->plt_eh_frame->output_offset 4949 + PLT_FDE_START_OFFSET; 4950 bfd_put_signed_32 (dynobj, plt_start - eh_frame_start, 4951 htab->plt_eh_frame->contents 4952 + PLT_FDE_START_OFFSET); 4953 } 4954 if (htab->plt_eh_frame->sec_info_type 4955 == SEC_INFO_TYPE_EH_FRAME) 4956 { 4957 if (! _bfd_elf_write_section_eh_frame (output_bfd, info, 4958 htab->plt_eh_frame, 4959 htab->plt_eh_frame->contents)) 4960 return FALSE; 4961 } 4962 } 4963 4964 if (htab->elf.sgot && htab->elf.sgot->size > 0) 4965 elf_section_data (htab->elf.sgot->output_section)->this_hdr.sh_entsize = 4; 4966 4967 /* Fill PLT and GOT entries for local STT_GNU_IFUNC symbols. */ 4968 htab_traverse (htab->loc_hash_table, 4969 elf_i386_finish_local_dynamic_symbol, 4970 info); 4971 4972 return TRUE; 4973 } 4974 4975 /* Return address for Ith PLT stub in section PLT, for relocation REL 4976 or (bfd_vma) -1 if it should not be included. */ 4977 4978 static bfd_vma 4979 elf_i386_plt_sym_val (bfd_vma i, const asection *plt, 4980 const arelent *rel ATTRIBUTE_UNUSED) 4981 { 4982 return plt->vma + (i + 1) * GET_PLT_ENTRY_SIZE (plt->owner); 4983 } 4984 4985 /* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */ 4986 4987 static bfd_boolean 4988 elf_i386_hash_symbol (struct elf_link_hash_entry *h) 4989 { 4990 if (h->plt.offset != (bfd_vma) -1 4991 && !h->def_regular 4992 && !h->pointer_equality_needed) 4993 return FALSE; 4994 4995 return _bfd_elf_hash_symbol (h); 4996 } 4997 4998 /* Hook called by the linker routine which adds symbols from an object 4999 file. */ 5000 5001 static bfd_boolean 5002 elf_i386_add_symbol_hook (bfd * abfd, 5003 struct bfd_link_info * info ATTRIBUTE_UNUSED, 5004 Elf_Internal_Sym * sym, 5005 const char ** namep ATTRIBUTE_UNUSED, 5006 flagword * flagsp ATTRIBUTE_UNUSED, 5007 asection ** secp ATTRIBUTE_UNUSED, 5008 bfd_vma * valp ATTRIBUTE_UNUSED) 5009 { 5010 if ((abfd->flags & DYNAMIC) == 0 5011 && (ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC 5012 || ELF_ST_BIND (sym->st_info) == STB_GNU_UNIQUE)) 5013 elf_tdata (info->output_bfd)->has_gnu_symbols = TRUE; 5014 5015 return TRUE; 5016 } 5017 5018 #define TARGET_LITTLE_SYM bfd_elf32_i386_vec 5019 #define TARGET_LITTLE_NAME "elf32-i386" 5020 #define ELF_ARCH bfd_arch_i386 5021 #define ELF_TARGET_ID I386_ELF_DATA 5022 #define ELF_MACHINE_CODE EM_386 5023 #define ELF_MAXPAGESIZE 0x1000 5024 5025 #define elf_backend_can_gc_sections 1 5026 #define elf_backend_can_refcount 1 5027 #define elf_backend_want_got_plt 1 5028 #define elf_backend_plt_readonly 1 5029 #define elf_backend_want_plt_sym 0 5030 #define elf_backend_got_header_size 12 5031 #define elf_backend_plt_alignment 4 5032 5033 /* Support RELA for objdump of prelink objects. */ 5034 #define elf_info_to_howto elf_i386_info_to_howto_rel 5035 #define elf_info_to_howto_rel elf_i386_info_to_howto_rel 5036 5037 #define bfd_elf32_mkobject elf_i386_mkobject 5038 5039 #define bfd_elf32_bfd_is_local_label_name elf_i386_is_local_label_name 5040 #define bfd_elf32_bfd_link_hash_table_create elf_i386_link_hash_table_create 5041 #define bfd_elf32_bfd_link_hash_table_free elf_i386_link_hash_table_free 5042 #define bfd_elf32_bfd_reloc_type_lookup elf_i386_reloc_type_lookup 5043 #define bfd_elf32_bfd_reloc_name_lookup elf_i386_reloc_name_lookup 5044 5045 #define elf_backend_adjust_dynamic_symbol elf_i386_adjust_dynamic_symbol 5046 #define elf_backend_relocs_compatible _bfd_elf_relocs_compatible 5047 #define elf_backend_check_relocs elf_i386_check_relocs 5048 #define elf_backend_copy_indirect_symbol elf_i386_copy_indirect_symbol 5049 #define elf_backend_create_dynamic_sections elf_i386_create_dynamic_sections 5050 #define elf_backend_fake_sections elf_i386_fake_sections 5051 #define elf_backend_finish_dynamic_sections elf_i386_finish_dynamic_sections 5052 #define elf_backend_finish_dynamic_symbol elf_i386_finish_dynamic_symbol 5053 #define elf_backend_gc_mark_hook elf_i386_gc_mark_hook 5054 #define elf_backend_gc_sweep_hook elf_i386_gc_sweep_hook 5055 #define elf_backend_grok_prstatus elf_i386_grok_prstatus 5056 #define elf_backend_grok_psinfo elf_i386_grok_psinfo 5057 #define elf_backend_reloc_type_class elf_i386_reloc_type_class 5058 #define elf_backend_relocate_section elf_i386_relocate_section 5059 #define elf_backend_size_dynamic_sections elf_i386_size_dynamic_sections 5060 #define elf_backend_always_size_sections elf_i386_always_size_sections 5061 #define elf_backend_omit_section_dynsym \ 5062 ((bfd_boolean (*) (bfd *, struct bfd_link_info *, asection *)) bfd_true) 5063 #define elf_backend_plt_sym_val elf_i386_plt_sym_val 5064 #define elf_backend_hash_symbol elf_i386_hash_symbol 5065 #define elf_backend_add_symbol_hook elf_i386_add_symbol_hook 5066 #undef elf_backend_post_process_headers 5067 #define elf_backend_post_process_headers _bfd_elf_set_osabi 5068 5069 #include "elf32-target.h" 5070 5071 /* FreeBSD support. */ 5072 5073 #undef TARGET_LITTLE_SYM 5074 #define TARGET_LITTLE_SYM bfd_elf32_i386_freebsd_vec 5075 #undef TARGET_LITTLE_NAME 5076 #define TARGET_LITTLE_NAME "elf32-i386-freebsd" 5077 #undef ELF_OSABI 5078 #define ELF_OSABI ELFOSABI_FREEBSD 5079 5080 /* The kernel recognizes executables as valid only if they carry a 5081 "FreeBSD" label in the ELF header. So we put this label on all 5082 executables and (for simplicity) also all other object files. */ 5083 5084 static void 5085 elf_i386_fbsd_post_process_headers (bfd *abfd, struct bfd_link_info *info) 5086 { 5087 _bfd_elf_set_osabi (abfd, info); 5088 5089 #ifdef OLD_FREEBSD_ABI_LABEL 5090 /* The ABI label supported by FreeBSD <= 4.0 is quite nonstandard. */ 5091 memcpy (&i_ehdrp->e_ident[EI_ABIVERSION], "FreeBSD", 8); 5092 #endif 5093 } 5094 5095 #undef elf_backend_post_process_headers 5096 #define elf_backend_post_process_headers elf_i386_fbsd_post_process_headers 5097 #undef elf32_bed 5098 #define elf32_bed elf32_i386_fbsd_bed 5099 5100 #undef elf_backend_add_symbol_hook 5101 5102 #include "elf32-target.h" 5103 5104 /* Solaris 2. */ 5105 5106 #undef TARGET_LITTLE_SYM 5107 #define TARGET_LITTLE_SYM bfd_elf32_i386_sol2_vec 5108 #undef TARGET_LITTLE_NAME 5109 #define TARGET_LITTLE_NAME "elf32-i386-sol2" 5110 5111 /* Restore default: we cannot use ELFOSABI_SOLARIS, otherwise ELFOSABI_NONE 5112 objects won't be recognized. */ 5113 #undef ELF_OSABI 5114 5115 #undef elf32_bed 5116 #define elf32_bed elf32_i386_sol2_bed 5117 5118 /* The 32-bit static TLS arena size is rounded to the nearest 8-byte 5119 boundary. */ 5120 #undef elf_backend_static_tls_alignment 5121 #define elf_backend_static_tls_alignment 8 5122 5123 /* The Solaris 2 ABI requires a plt symbol on all platforms. 5124 5125 Cf. Linker and Libraries Guide, Ch. 2, Link-Editor, Generating the Output 5126 File, p.63. */ 5127 #undef elf_backend_want_plt_sym 5128 #define elf_backend_want_plt_sym 1 5129 5130 #include "elf32-target.h" 5131 5132 /* Native Client support. */ 5133 5134 #undef TARGET_LITTLE_SYM 5135 #define TARGET_LITTLE_SYM bfd_elf32_i386_nacl_vec 5136 #undef TARGET_LITTLE_NAME 5137 #define TARGET_LITTLE_NAME "elf32-i386-nacl" 5138 #undef elf32_bed 5139 #define elf32_bed elf32_i386_nacl_bed 5140 5141 #undef ELF_MAXPAGESIZE 5142 #define ELF_MAXPAGESIZE 0x10000 5143 5144 /* Restore defaults. */ 5145 #undef ELF_OSABI 5146 #undef elf_backend_want_plt_sym 5147 #define elf_backend_want_plt_sym 0 5148 #undef elf_backend_post_process_headers 5149 #define elf_backend_post_process_headers _bfd_elf_set_osabi 5150 #undef elf_backend_static_tls_alignment 5151 5152 /* NaCl uses substantially different PLT entries for the same effects. */ 5153 5154 #undef elf_backend_plt_alignment 5155 #define elf_backend_plt_alignment 5 5156 #define NACL_PLT_ENTRY_SIZE 64 5157 #define NACLMASK 0xe0 /* 32-byte alignment mask. */ 5158 5159 static const bfd_byte elf_i386_nacl_plt0_entry[] = 5160 { 5161 0xff, 0x35, /* pushl contents of address */ 5162 0, 0, 0, 0, /* replaced with address of .got + 4. */ 5163 0x8b, 0x0d, /* movl contents of address, %ecx */ 5164 0, 0, 0, 0, /* replaced with address of .got + 8. */ 5165 0x83, 0xe1, NACLMASK, /* andl $NACLMASK, %ecx */ 5166 0xff, 0xe1 /* jmp *%ecx */ 5167 }; 5168 5169 static const bfd_byte elf_i386_nacl_plt_entry[NACL_PLT_ENTRY_SIZE] = 5170 { 5171 0x8b, 0x0d, /* movl contents of address, %ecx */ 5172 0, 0, 0, 0, /* replaced with GOT slot address. */ 5173 0x83, 0xe1, NACLMASK, /* andl $NACLMASK, %ecx */ 5174 0xff, 0xe1, /* jmp *%ecx */ 5175 5176 /* Pad to the next 32-byte boundary with nop instructions. */ 5177 0x90, 5178 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 5179 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 5180 5181 /* Lazy GOT entries point here (32-byte aligned). */ 5182 0x68, /* pushl immediate */ 5183 0, 0, 0, 0, /* replaced with reloc offset. */ 5184 0xe9, /* jmp relative */ 5185 0, 0, 0, 0, /* replaced with offset to .plt. */ 5186 5187 /* Pad to the next 32-byte boundary with nop instructions. */ 5188 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 5189 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 5190 0x90, 0x90 5191 }; 5192 5193 static const bfd_byte 5194 elf_i386_nacl_pic_plt0_entry[sizeof (elf_i386_nacl_plt0_entry)] = 5195 { 5196 0xff, 0x73, 0x04, /* pushl 4(%ebx) */ 5197 0x8b, 0x4b, 0x08, /* mov 0x8(%ebx), %ecx */ 5198 0x83, 0xe1, 0xe0, /* and $NACLMASK, %ecx */ 5199 0xff, 0xe1, /* jmp *%ecx */ 5200 5201 /* This is expected to be the same size as elf_i386_nacl_plt0_entry, 5202 so pad to that size with nop instructions. */ 5203 0x90, 0x90, 0x90, 0x90, 0x90, 0x90 5204 }; 5205 5206 static const bfd_byte elf_i386_nacl_pic_plt_entry[NACL_PLT_ENTRY_SIZE] = 5207 { 5208 0x8b, 0x8b, /* movl offset(%ebx), %ecx */ 5209 0, 0, 0, 0, /* replaced with offset of this symbol in .got. */ 5210 0x83, 0xe1, 0xe0, /* andl $NACLMASK, %ecx */ 5211 0xff, 0xe1, /* jmp *%ecx */ 5212 5213 /* Pad to the next 32-byte boundary with nop instructions. */ 5214 0x90, 5215 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 5216 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 5217 5218 /* Lazy GOT entries point here (32-byte aligned). */ 5219 0x68, /* pushl immediate */ 5220 0, 0, 0, 0, /* replaced with offset into relocation table. */ 5221 0xe9, /* jmp relative */ 5222 0, 0, 0, 0, /* replaced with offset to start of .plt. */ 5223 5224 /* Pad to the next 32-byte boundary with nop instructions. */ 5225 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 5226 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 5227 0x90, 0x90 5228 }; 5229 5230 static const bfd_byte elf_i386_nacl_eh_frame_plt[] = 5231 { 5232 #if (PLT_CIE_LENGTH != 20 \ 5233 || PLT_FDE_LENGTH != 36 \ 5234 || PLT_FDE_START_OFFSET != 4 + PLT_CIE_LENGTH + 8 \ 5235 || PLT_FDE_LEN_OFFSET != 4 + PLT_CIE_LENGTH + 12) 5236 # error "Need elf_i386_backend_data parameters for eh_frame_plt offsets!" 5237 #endif 5238 PLT_CIE_LENGTH, 0, 0, 0, /* CIE length */ 5239 0, 0, 0, 0, /* CIE ID */ 5240 1, /* CIE version */ 5241 'z', 'R', 0, /* Augmentation string */ 5242 1, /* Code alignment factor */ 5243 0x7c, /* Data alignment factor: -4 */ 5244 8, /* Return address column */ 5245 1, /* Augmentation size */ 5246 DW_EH_PE_pcrel | DW_EH_PE_sdata4, /* FDE encoding */ 5247 DW_CFA_def_cfa, 4, 4, /* DW_CFA_def_cfa: r4 (esp) ofs 4 */ 5248 DW_CFA_offset + 8, 1, /* DW_CFA_offset: r8 (eip) at cfa-4 */ 5249 DW_CFA_nop, DW_CFA_nop, 5250 5251 PLT_FDE_LENGTH, 0, 0, 0, /* FDE length */ 5252 PLT_CIE_LENGTH + 8, 0, 0, 0, /* CIE pointer */ 5253 0, 0, 0, 0, /* R_386_PC32 .plt goes here */ 5254 0, 0, 0, 0, /* .plt size goes here */ 5255 0, /* Augmentation size */ 5256 DW_CFA_def_cfa_offset, 8, /* DW_CFA_def_cfa_offset: 8 */ 5257 DW_CFA_advance_loc + 6, /* DW_CFA_advance_loc: 6 to __PLT__+6 */ 5258 DW_CFA_def_cfa_offset, 12, /* DW_CFA_def_cfa_offset: 12 */ 5259 DW_CFA_advance_loc + 58, /* DW_CFA_advance_loc: 58 to __PLT__+64 */ 5260 DW_CFA_def_cfa_expression, /* DW_CFA_def_cfa_expression */ 5261 13, /* Block length */ 5262 DW_OP_breg4, 4, /* DW_OP_breg4 (esp): 4 */ 5263 DW_OP_breg8, 0, /* DW_OP_breg8 (eip): 0 */ 5264 DW_OP_const1u, 63, DW_OP_and, DW_OP_const1u, 37, DW_OP_ge, 5265 DW_OP_lit2, DW_OP_shl, DW_OP_plus, 5266 DW_CFA_nop, DW_CFA_nop 5267 }; 5268 5269 static const struct elf_i386_plt_layout elf_i386_nacl_plt = 5270 { 5271 elf_i386_nacl_plt0_entry, /* plt0_entry */ 5272 sizeof (elf_i386_nacl_plt0_entry), /* plt0_entry_size */ 5273 2, /* plt0_got1_offset */ 5274 8, /* plt0_got2_offset */ 5275 elf_i386_nacl_plt_entry, /* plt_entry */ 5276 NACL_PLT_ENTRY_SIZE, /* plt_entry_size */ 5277 2, /* plt_got_offset */ 5278 33, /* plt_reloc_offset */ 5279 38, /* plt_plt_offset */ 5280 32, /* plt_lazy_offset */ 5281 elf_i386_nacl_pic_plt0_entry, /* pic_plt0_entry */ 5282 elf_i386_nacl_pic_plt_entry, /* pic_plt_entry */ 5283 elf_i386_nacl_eh_frame_plt, /* eh_frame_plt */ 5284 sizeof (elf_i386_nacl_eh_frame_plt),/* eh_frame_plt_size */ 5285 }; 5286 5287 static const struct elf_i386_backend_data elf_i386_nacl_arch_bed = 5288 { 5289 &elf_i386_nacl_plt, /* plt */ 5290 0x90, /* plt0_pad_byte: nop insn */ 5291 0, /* is_vxworks */ 5292 }; 5293 5294 #undef elf_backend_arch_data 5295 #define elf_backend_arch_data &elf_i386_nacl_arch_bed 5296 5297 #undef elf_backend_modify_segment_map 5298 #define elf_backend_modify_segment_map nacl_modify_segment_map 5299 #undef elf_backend_modify_program_headers 5300 #define elf_backend_modify_program_headers nacl_modify_program_headers 5301 5302 #include "elf32-target.h" 5303 5304 /* Restore defaults. */ 5305 #undef elf_backend_modify_segment_map 5306 #undef elf_backend_modify_program_headers 5307 5308 /* VxWorks support. */ 5309 5310 #undef TARGET_LITTLE_SYM 5311 #define TARGET_LITTLE_SYM bfd_elf32_i386_vxworks_vec 5312 #undef TARGET_LITTLE_NAME 5313 #define TARGET_LITTLE_NAME "elf32-i386-vxworks" 5314 #undef ELF_OSABI 5315 #undef elf_backend_plt_alignment 5316 #define elf_backend_plt_alignment 4 5317 5318 static const struct elf_i386_backend_data elf_i386_vxworks_arch_bed = 5319 { 5320 &elf_i386_plt, /* plt */ 5321 0x90, /* plt0_pad_byte */ 5322 1, /* is_vxworks */ 5323 }; 5324 5325 #undef elf_backend_arch_data 5326 #define elf_backend_arch_data &elf_i386_vxworks_arch_bed 5327 5328 #undef elf_backend_relocs_compatible 5329 #undef elf_backend_post_process_headers 5330 #undef elf_backend_add_symbol_hook 5331 #define elf_backend_add_symbol_hook \ 5332 elf_vxworks_add_symbol_hook 5333 #undef elf_backend_link_output_symbol_hook 5334 #define elf_backend_link_output_symbol_hook \ 5335 elf_vxworks_link_output_symbol_hook 5336 #undef elf_backend_emit_relocs 5337 #define elf_backend_emit_relocs elf_vxworks_emit_relocs 5338 #undef elf_backend_final_write_processing 5339 #define elf_backend_final_write_processing \ 5340 elf_vxworks_final_write_processing 5341 #undef elf_backend_static_tls_alignment 5342 5343 /* On VxWorks, we emit relocations against _PROCEDURE_LINKAGE_TABLE_, so 5344 define it. */ 5345 #undef elf_backend_want_plt_sym 5346 #define elf_backend_want_plt_sym 1 5347 5348 #undef elf32_bed 5349 #define elf32_bed elf32_i386_vxworks_bed 5350 5351 #include "elf32-target.h" 5352