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 Free Software Foundation, Inc. 4 5 This file is part of BFD, the Binary File Descriptor library. 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program; if not, write to the Free Software 19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 20 MA 02110-1301, USA. */ 21 22 #include "sysdep.h" 23 #include "bfd.h" 24 #include "bfdlink.h" 25 #include "libbfd.h" 26 #include "elf-bfd.h" 27 #include "elf-vxworks.h" 28 #include "bfd_stdint.h" 29 30 /* 386 uses REL relocations instead of RELA. */ 31 #define USE_REL 1 32 33 #include "elf/i386.h" 34 35 static reloc_howto_type elf_howto_table[]= 36 { 37 HOWTO(R_386_NONE, 0, 0, 0, FALSE, 0, complain_overflow_bitfield, 38 bfd_elf_generic_reloc, "R_386_NONE", 39 TRUE, 0x00000000, 0x00000000, FALSE), 40 HOWTO(R_386_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 41 bfd_elf_generic_reloc, "R_386_32", 42 TRUE, 0xffffffff, 0xffffffff, FALSE), 43 HOWTO(R_386_PC32, 0, 2, 32, TRUE, 0, complain_overflow_bitfield, 44 bfd_elf_generic_reloc, "R_386_PC32", 45 TRUE, 0xffffffff, 0xffffffff, TRUE), 46 HOWTO(R_386_GOT32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 47 bfd_elf_generic_reloc, "R_386_GOT32", 48 TRUE, 0xffffffff, 0xffffffff, FALSE), 49 HOWTO(R_386_PLT32, 0, 2, 32, TRUE, 0, complain_overflow_bitfield, 50 bfd_elf_generic_reloc, "R_386_PLT32", 51 TRUE, 0xffffffff, 0xffffffff, TRUE), 52 HOWTO(R_386_COPY, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 53 bfd_elf_generic_reloc, "R_386_COPY", 54 TRUE, 0xffffffff, 0xffffffff, FALSE), 55 HOWTO(R_386_GLOB_DAT, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 56 bfd_elf_generic_reloc, "R_386_GLOB_DAT", 57 TRUE, 0xffffffff, 0xffffffff, FALSE), 58 HOWTO(R_386_JUMP_SLOT, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 59 bfd_elf_generic_reloc, "R_386_JUMP_SLOT", 60 TRUE, 0xffffffff, 0xffffffff, FALSE), 61 HOWTO(R_386_RELATIVE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 62 bfd_elf_generic_reloc, "R_386_RELATIVE", 63 TRUE, 0xffffffff, 0xffffffff, FALSE), 64 HOWTO(R_386_GOTOFF, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 65 bfd_elf_generic_reloc, "R_386_GOTOFF", 66 TRUE, 0xffffffff, 0xffffffff, FALSE), 67 HOWTO(R_386_GOTPC, 0, 2, 32, TRUE, 0, complain_overflow_bitfield, 68 bfd_elf_generic_reloc, "R_386_GOTPC", 69 TRUE, 0xffffffff, 0xffffffff, TRUE), 70 71 /* We have a gap in the reloc numbers here. 72 R_386_standard counts the number up to this point, and 73 R_386_ext_offset is the value to subtract from a reloc type of 74 R_386_16 thru R_386_PC8 to form an index into this table. */ 75 #define R_386_standard (R_386_GOTPC + 1) 76 #define R_386_ext_offset (R_386_TLS_TPOFF - R_386_standard) 77 78 /* These relocs are a GNU extension. */ 79 HOWTO(R_386_TLS_TPOFF, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 80 bfd_elf_generic_reloc, "R_386_TLS_TPOFF", 81 TRUE, 0xffffffff, 0xffffffff, FALSE), 82 HOWTO(R_386_TLS_IE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 83 bfd_elf_generic_reloc, "R_386_TLS_IE", 84 TRUE, 0xffffffff, 0xffffffff, FALSE), 85 HOWTO(R_386_TLS_GOTIE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 86 bfd_elf_generic_reloc, "R_386_TLS_GOTIE", 87 TRUE, 0xffffffff, 0xffffffff, FALSE), 88 HOWTO(R_386_TLS_LE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 89 bfd_elf_generic_reloc, "R_386_TLS_LE", 90 TRUE, 0xffffffff, 0xffffffff, FALSE), 91 HOWTO(R_386_TLS_GD, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 92 bfd_elf_generic_reloc, "R_386_TLS_GD", 93 TRUE, 0xffffffff, 0xffffffff, FALSE), 94 HOWTO(R_386_TLS_LDM, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 95 bfd_elf_generic_reloc, "R_386_TLS_LDM", 96 TRUE, 0xffffffff, 0xffffffff, FALSE), 97 HOWTO(R_386_16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield, 98 bfd_elf_generic_reloc, "R_386_16", 99 TRUE, 0xffff, 0xffff, FALSE), 100 HOWTO(R_386_PC16, 0, 1, 16, TRUE, 0, complain_overflow_bitfield, 101 bfd_elf_generic_reloc, "R_386_PC16", 102 TRUE, 0xffff, 0xffff, TRUE), 103 HOWTO(R_386_8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield, 104 bfd_elf_generic_reloc, "R_386_8", 105 TRUE, 0xff, 0xff, FALSE), 106 HOWTO(R_386_PC8, 0, 0, 8, TRUE, 0, complain_overflow_signed, 107 bfd_elf_generic_reloc, "R_386_PC8", 108 TRUE, 0xff, 0xff, TRUE), 109 110 #define R_386_ext (R_386_PC8 + 1 - R_386_ext_offset) 111 #define R_386_tls_offset (R_386_TLS_LDO_32 - R_386_ext) 112 /* These are common with Solaris TLS implementation. */ 113 HOWTO(R_386_TLS_LDO_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 114 bfd_elf_generic_reloc, "R_386_TLS_LDO_32", 115 TRUE, 0xffffffff, 0xffffffff, FALSE), 116 HOWTO(R_386_TLS_IE_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 117 bfd_elf_generic_reloc, "R_386_TLS_IE_32", 118 TRUE, 0xffffffff, 0xffffffff, FALSE), 119 HOWTO(R_386_TLS_LE_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 120 bfd_elf_generic_reloc, "R_386_TLS_LE_32", 121 TRUE, 0xffffffff, 0xffffffff, FALSE), 122 HOWTO(R_386_TLS_DTPMOD32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 123 bfd_elf_generic_reloc, "R_386_TLS_DTPMOD32", 124 TRUE, 0xffffffff, 0xffffffff, FALSE), 125 HOWTO(R_386_TLS_DTPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 126 bfd_elf_generic_reloc, "R_386_TLS_DTPOFF32", 127 TRUE, 0xffffffff, 0xffffffff, FALSE), 128 HOWTO(R_386_TLS_TPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 129 bfd_elf_generic_reloc, "R_386_TLS_TPOFF32", 130 TRUE, 0xffffffff, 0xffffffff, FALSE), 131 EMPTY_HOWTO (38), 132 HOWTO(R_386_TLS_GOTDESC, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 133 bfd_elf_generic_reloc, "R_386_TLS_GOTDESC", 134 TRUE, 0xffffffff, 0xffffffff, FALSE), 135 HOWTO(R_386_TLS_DESC_CALL, 0, 0, 0, FALSE, 0, complain_overflow_dont, 136 bfd_elf_generic_reloc, "R_386_TLS_DESC_CALL", 137 FALSE, 0, 0, FALSE), 138 HOWTO(R_386_TLS_DESC, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, 139 bfd_elf_generic_reloc, "R_386_TLS_DESC", 140 TRUE, 0xffffffff, 0xffffffff, FALSE), 141 142 /* Another gap. */ 143 #define R_386_tls (R_386_TLS_DESC + 1 - R_386_tls_offset) 144 #define R_386_vt_offset (R_386_GNU_VTINHERIT - R_386_tls) 145 146 /* GNU extension to record C++ vtable hierarchy. */ 147 HOWTO (R_386_GNU_VTINHERIT, /* type */ 148 0, /* rightshift */ 149 2, /* size (0 = byte, 1 = short, 2 = long) */ 150 0, /* bitsize */ 151 FALSE, /* pc_relative */ 152 0, /* bitpos */ 153 complain_overflow_dont, /* complain_on_overflow */ 154 NULL, /* special_function */ 155 "R_386_GNU_VTINHERIT", /* name */ 156 FALSE, /* partial_inplace */ 157 0, /* src_mask */ 158 0, /* dst_mask */ 159 FALSE), /* pcrel_offset */ 160 161 /* GNU extension to record C++ vtable member usage. */ 162 HOWTO (R_386_GNU_VTENTRY, /* type */ 163 0, /* rightshift */ 164 2, /* size (0 = byte, 1 = short, 2 = long) */ 165 0, /* bitsize */ 166 FALSE, /* pc_relative */ 167 0, /* bitpos */ 168 complain_overflow_dont, /* complain_on_overflow */ 169 _bfd_elf_rel_vtable_reloc_fn, /* special_function */ 170 "R_386_GNU_VTENTRY", /* name */ 171 FALSE, /* partial_inplace */ 172 0, /* src_mask */ 173 0, /* dst_mask */ 174 FALSE) /* pcrel_offset */ 175 176 #define R_386_vt (R_386_GNU_VTENTRY + 1 - R_386_vt_offset) 177 178 }; 179 180 #ifdef DEBUG_GEN_RELOC 181 #define TRACE(str) \ 182 fprintf (stderr, "i386 bfd reloc lookup %d (%s)\n", code, str) 183 #else 184 #define TRACE(str) 185 #endif 186 187 static reloc_howto_type * 188 elf_i386_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED, 189 bfd_reloc_code_real_type code) 190 { 191 switch (code) 192 { 193 case BFD_RELOC_NONE: 194 TRACE ("BFD_RELOC_NONE"); 195 return &elf_howto_table[R_386_NONE]; 196 197 case BFD_RELOC_32: 198 TRACE ("BFD_RELOC_32"); 199 return &elf_howto_table[R_386_32]; 200 201 case BFD_RELOC_CTOR: 202 TRACE ("BFD_RELOC_CTOR"); 203 return &elf_howto_table[R_386_32]; 204 205 case BFD_RELOC_32_PCREL: 206 TRACE ("BFD_RELOC_PC32"); 207 return &elf_howto_table[R_386_PC32]; 208 209 case BFD_RELOC_386_GOT32: 210 TRACE ("BFD_RELOC_386_GOT32"); 211 return &elf_howto_table[R_386_GOT32]; 212 213 case BFD_RELOC_386_PLT32: 214 TRACE ("BFD_RELOC_386_PLT32"); 215 return &elf_howto_table[R_386_PLT32]; 216 217 case BFD_RELOC_386_COPY: 218 TRACE ("BFD_RELOC_386_COPY"); 219 return &elf_howto_table[R_386_COPY]; 220 221 case BFD_RELOC_386_GLOB_DAT: 222 TRACE ("BFD_RELOC_386_GLOB_DAT"); 223 return &elf_howto_table[R_386_GLOB_DAT]; 224 225 case BFD_RELOC_386_JUMP_SLOT: 226 TRACE ("BFD_RELOC_386_JUMP_SLOT"); 227 return &elf_howto_table[R_386_JUMP_SLOT]; 228 229 case BFD_RELOC_386_RELATIVE: 230 TRACE ("BFD_RELOC_386_RELATIVE"); 231 return &elf_howto_table[R_386_RELATIVE]; 232 233 case BFD_RELOC_386_GOTOFF: 234 TRACE ("BFD_RELOC_386_GOTOFF"); 235 return &elf_howto_table[R_386_GOTOFF]; 236 237 case BFD_RELOC_386_GOTPC: 238 TRACE ("BFD_RELOC_386_GOTPC"); 239 return &elf_howto_table[R_386_GOTPC]; 240 241 /* These relocs are a GNU extension. */ 242 case BFD_RELOC_386_TLS_TPOFF: 243 TRACE ("BFD_RELOC_386_TLS_TPOFF"); 244 return &elf_howto_table[R_386_TLS_TPOFF - R_386_ext_offset]; 245 246 case BFD_RELOC_386_TLS_IE: 247 TRACE ("BFD_RELOC_386_TLS_IE"); 248 return &elf_howto_table[R_386_TLS_IE - R_386_ext_offset]; 249 250 case BFD_RELOC_386_TLS_GOTIE: 251 TRACE ("BFD_RELOC_386_TLS_GOTIE"); 252 return &elf_howto_table[R_386_TLS_GOTIE - R_386_ext_offset]; 253 254 case BFD_RELOC_386_TLS_LE: 255 TRACE ("BFD_RELOC_386_TLS_LE"); 256 return &elf_howto_table[R_386_TLS_LE - R_386_ext_offset]; 257 258 case BFD_RELOC_386_TLS_GD: 259 TRACE ("BFD_RELOC_386_TLS_GD"); 260 return &elf_howto_table[R_386_TLS_GD - R_386_ext_offset]; 261 262 case BFD_RELOC_386_TLS_LDM: 263 TRACE ("BFD_RELOC_386_TLS_LDM"); 264 return &elf_howto_table[R_386_TLS_LDM - R_386_ext_offset]; 265 266 case BFD_RELOC_16: 267 TRACE ("BFD_RELOC_16"); 268 return &elf_howto_table[R_386_16 - R_386_ext_offset]; 269 270 case BFD_RELOC_16_PCREL: 271 TRACE ("BFD_RELOC_16_PCREL"); 272 return &elf_howto_table[R_386_PC16 - R_386_ext_offset]; 273 274 case BFD_RELOC_8: 275 TRACE ("BFD_RELOC_8"); 276 return &elf_howto_table[R_386_8 - R_386_ext_offset]; 277 278 case BFD_RELOC_8_PCREL: 279 TRACE ("BFD_RELOC_8_PCREL"); 280 return &elf_howto_table[R_386_PC8 - R_386_ext_offset]; 281 282 /* Common with Sun TLS implementation. */ 283 case BFD_RELOC_386_TLS_LDO_32: 284 TRACE ("BFD_RELOC_386_TLS_LDO_32"); 285 return &elf_howto_table[R_386_TLS_LDO_32 - R_386_tls_offset]; 286 287 case BFD_RELOC_386_TLS_IE_32: 288 TRACE ("BFD_RELOC_386_TLS_IE_32"); 289 return &elf_howto_table[R_386_TLS_IE_32 - R_386_tls_offset]; 290 291 case BFD_RELOC_386_TLS_LE_32: 292 TRACE ("BFD_RELOC_386_TLS_LE_32"); 293 return &elf_howto_table[R_386_TLS_LE_32 - R_386_tls_offset]; 294 295 case BFD_RELOC_386_TLS_DTPMOD32: 296 TRACE ("BFD_RELOC_386_TLS_DTPMOD32"); 297 return &elf_howto_table[R_386_TLS_DTPMOD32 - R_386_tls_offset]; 298 299 case BFD_RELOC_386_TLS_DTPOFF32: 300 TRACE ("BFD_RELOC_386_TLS_DTPOFF32"); 301 return &elf_howto_table[R_386_TLS_DTPOFF32 - R_386_tls_offset]; 302 303 case BFD_RELOC_386_TLS_TPOFF32: 304 TRACE ("BFD_RELOC_386_TLS_TPOFF32"); 305 return &elf_howto_table[R_386_TLS_TPOFF32 - R_386_tls_offset]; 306 307 case BFD_RELOC_386_TLS_GOTDESC: 308 TRACE ("BFD_RELOC_386_TLS_GOTDESC"); 309 return &elf_howto_table[R_386_TLS_GOTDESC - R_386_tls_offset]; 310 311 case BFD_RELOC_386_TLS_DESC_CALL: 312 TRACE ("BFD_RELOC_386_TLS_DESC_CALL"); 313 return &elf_howto_table[R_386_TLS_DESC_CALL - R_386_tls_offset]; 314 315 case BFD_RELOC_386_TLS_DESC: 316 TRACE ("BFD_RELOC_386_TLS_DESC"); 317 return &elf_howto_table[R_386_TLS_DESC - R_386_tls_offset]; 318 319 case BFD_RELOC_VTABLE_INHERIT: 320 TRACE ("BFD_RELOC_VTABLE_INHERIT"); 321 return &elf_howto_table[R_386_GNU_VTINHERIT - R_386_vt_offset]; 322 323 case BFD_RELOC_VTABLE_ENTRY: 324 TRACE ("BFD_RELOC_VTABLE_ENTRY"); 325 return &elf_howto_table[R_386_GNU_VTENTRY - R_386_vt_offset]; 326 327 default: 328 break; 329 } 330 331 TRACE ("Unknown"); 332 return 0; 333 } 334 335 static reloc_howto_type * 336 elf_i386_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED, 337 const char *r_name) 338 { 339 unsigned int i; 340 341 for (i = 0; i < sizeof (elf_howto_table) / sizeof (elf_howto_table[0]); i++) 342 if (elf_howto_table[i].name != NULL 343 && strcasecmp (elf_howto_table[i].name, r_name) == 0) 344 return &elf_howto_table[i]; 345 346 return NULL; 347 } 348 349 static reloc_howto_type * 350 elf_i386_rtype_to_howto (bfd *abfd, unsigned r_type) 351 { 352 unsigned int indx; 353 354 if ((indx = r_type) >= R_386_standard 355 && ((indx = r_type - R_386_ext_offset) - R_386_standard 356 >= R_386_ext - R_386_standard) 357 && ((indx = r_type - R_386_tls_offset) - R_386_ext 358 >= R_386_tls - R_386_ext) 359 && ((indx = r_type - R_386_vt_offset) - R_386_tls 360 >= R_386_vt - R_386_tls)) 361 { 362 (*_bfd_error_handler) (_("%B: invalid relocation type %d"), 363 abfd, (int) r_type); 364 indx = R_386_NONE; 365 } 366 BFD_ASSERT (elf_howto_table [indx].type == r_type); 367 return &elf_howto_table[indx]; 368 } 369 370 static void 371 elf_i386_info_to_howto_rel (bfd *abfd ATTRIBUTE_UNUSED, 372 arelent *cache_ptr, 373 Elf_Internal_Rela *dst) 374 { 375 unsigned int r_type = ELF32_R_TYPE (dst->r_info); 376 cache_ptr->howto = elf_i386_rtype_to_howto (abfd, r_type); 377 } 378 379 /* Return whether a symbol name implies a local label. The UnixWare 380 2.1 cc generates temporary symbols that start with .X, so we 381 recognize them here. FIXME: do other SVR4 compilers also use .X?. 382 If so, we should move the .X recognition into 383 _bfd_elf_is_local_label_name. */ 384 385 static bfd_boolean 386 elf_i386_is_local_label_name (bfd *abfd, const char *name) 387 { 388 if (name[0] == '.' && name[1] == 'X') 389 return TRUE; 390 391 return _bfd_elf_is_local_label_name (abfd, name); 392 } 393 394 /* Support for core dump NOTE sections. */ 395 396 static bfd_boolean 397 elf_i386_grok_prstatus (bfd *abfd, Elf_Internal_Note *note) 398 { 399 int offset; 400 size_t size; 401 402 if (note->namesz == 8 && strcmp (note->namedata, "FreeBSD") == 0) 403 { 404 int pr_version = bfd_get_32 (abfd, note->descdata); 405 406 if (pr_version != 1) 407 return FALSE; 408 409 /* pr_cursig */ 410 elf_tdata (abfd)->core_signal = bfd_get_32 (abfd, note->descdata + 20); 411 412 /* pr_pid */ 413 elf_tdata (abfd)->core_pid = bfd_get_32 (abfd, note->descdata + 24); 414 415 /* pr_reg */ 416 offset = 28; 417 size = bfd_get_32 (abfd, note->descdata + 8); 418 } 419 else 420 { 421 switch (note->descsz) 422 { 423 default: 424 return FALSE; 425 426 case 144: /* Linux/i386 */ 427 /* pr_cursig */ 428 elf_tdata (abfd)->core_signal = bfd_get_16 (abfd, note->descdata + 12); 429 430 /* pr_pid */ 431 elf_tdata (abfd)->core_pid = bfd_get_32 (abfd, note->descdata + 24); 432 433 /* pr_reg */ 434 offset = 72; 435 size = 68; 436 437 break; 438 } 439 } 440 441 /* Make a ".reg/999" section. */ 442 return _bfd_elfcore_make_pseudosection (abfd, ".reg", 443 size, note->descpos + offset); 444 } 445 446 static bfd_boolean 447 elf_i386_grok_psinfo (bfd *abfd, Elf_Internal_Note *note) 448 { 449 if (note->namesz == 8 && strcmp (note->namedata, "FreeBSD") == 0) 450 { 451 int pr_version = bfd_get_32 (abfd, note->descdata); 452 453 if (pr_version != 1) 454 return FALSE; 455 456 elf_tdata (abfd)->core_program 457 = _bfd_elfcore_strndup (abfd, note->descdata + 8, 17); 458 elf_tdata (abfd)->core_command 459 = _bfd_elfcore_strndup (abfd, note->descdata + 25, 81); 460 } 461 else 462 { 463 switch (note->descsz) 464 { 465 default: 466 return FALSE; 467 468 case 124: /* Linux/i386 elf_prpsinfo. */ 469 elf_tdata (abfd)->core_program 470 = _bfd_elfcore_strndup (abfd, note->descdata + 28, 16); 471 elf_tdata (abfd)->core_command 472 = _bfd_elfcore_strndup (abfd, note->descdata + 44, 80); 473 } 474 } 475 476 /* Note that for some reason, a spurious space is tacked 477 onto the end of the args in some (at least one anyway) 478 implementations, so strip it off if it exists. */ 479 { 480 char *command = elf_tdata (abfd)->core_command; 481 int n = strlen (command); 482 483 if (0 < n && command[n - 1] == ' ') 484 command[n - 1] = '\0'; 485 } 486 487 return TRUE; 488 } 489 490 /* Functions for the i386 ELF linker. 491 492 In order to gain some understanding of code in this file without 493 knowing all the intricate details of the linker, note the 494 following: 495 496 Functions named elf_i386_* are called by external routines, other 497 functions are only called locally. elf_i386_* functions appear 498 in this file more or less in the order in which they are called 499 from external routines. eg. elf_i386_check_relocs is called 500 early in the link process, elf_i386_finish_dynamic_sections is 501 one of the last functions. */ 502 503 504 /* The name of the dynamic interpreter. This is put in the .interp 505 section. */ 506 507 #define ELF_DYNAMIC_INTERPRETER "/libexec/ld.elf_so" 508 509 /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid 510 copying dynamic variables from a shared lib into an app's dynbss 511 section, and instead use a dynamic relocation to point into the 512 shared lib. */ 513 #define ELIMINATE_COPY_RELOCS 1 514 515 /* The size in bytes of an entry in the procedure linkage table. */ 516 517 #define PLT_ENTRY_SIZE 16 518 519 /* The first entry in an absolute procedure linkage table looks like 520 this. See the SVR4 ABI i386 supplement to see how this works. 521 Will be padded to PLT_ENTRY_SIZE with htab->plt0_pad_byte. */ 522 523 static const bfd_byte elf_i386_plt0_entry[12] = 524 { 525 0xff, 0x35, /* pushl contents of address */ 526 0, 0, 0, 0, /* replaced with address of .got + 4. */ 527 0xff, 0x25, /* jmp indirect */ 528 0, 0, 0, 0 /* replaced with address of .got + 8. */ 529 }; 530 531 /* Subsequent entries in an absolute procedure linkage table look like 532 this. */ 533 534 static const bfd_byte elf_i386_plt_entry[PLT_ENTRY_SIZE] = 535 { 536 0xff, 0x25, /* jmp indirect */ 537 0, 0, 0, 0, /* replaced with address of this symbol in .got. */ 538 0x68, /* pushl immediate */ 539 0, 0, 0, 0, /* replaced with offset into relocation table. */ 540 0xe9, /* jmp relative */ 541 0, 0, 0, 0 /* replaced with offset to start of .plt. */ 542 }; 543 544 /* The first entry in a PIC procedure linkage table look like this. 545 Will be padded to PLT_ENTRY_SIZE with htab->plt0_pad_byte. */ 546 547 static const bfd_byte elf_i386_pic_plt0_entry[12] = 548 { 549 0xff, 0xb3, 4, 0, 0, 0, /* pushl 4(%ebx) */ 550 0xff, 0xa3, 8, 0, 0, 0 /* jmp *8(%ebx) */ 551 }; 552 553 /* Subsequent entries in a PIC procedure linkage table look like this. */ 554 555 static const bfd_byte elf_i386_pic_plt_entry[PLT_ENTRY_SIZE] = 556 { 557 0xff, 0xa3, /* jmp *offset(%ebx) */ 558 0, 0, 0, 0, /* replaced with offset of this symbol in .got. */ 559 0x68, /* pushl immediate */ 560 0, 0, 0, 0, /* replaced with offset into relocation table. */ 561 0xe9, /* jmp relative */ 562 0, 0, 0, 0 /* replaced with offset to start of .plt. */ 563 }; 564 565 /* On VxWorks, the .rel.plt.unloaded section has absolute relocations 566 for the PLTResolve stub and then for each PLT entry. */ 567 #define PLTRESOLVE_RELOCS_SHLIB 0 568 #define PLTRESOLVE_RELOCS 2 569 #define PLT_NON_JUMP_SLOT_RELOCS 2 570 571 /* The i386 linker needs to keep track of the number of relocs that it 572 decides to copy as dynamic relocs in check_relocs for each symbol. 573 This is so that it can later discard them if they are found to be 574 unnecessary. We store the information in a field extending the 575 regular ELF linker hash table. */ 576 577 struct elf_i386_dyn_relocs 578 { 579 struct elf_i386_dyn_relocs *next; 580 581 /* The input section of the reloc. */ 582 asection *sec; 583 584 /* Total number of relocs copied for the input section. */ 585 bfd_size_type count; 586 587 /* Number of pc-relative relocs copied for the input section. */ 588 bfd_size_type pc_count; 589 }; 590 591 /* i386 ELF linker hash entry. */ 592 593 struct elf_i386_link_hash_entry 594 { 595 struct elf_link_hash_entry elf; 596 597 /* Track dynamic relocs copied for this symbol. */ 598 struct elf_i386_dyn_relocs *dyn_relocs; 599 600 #define GOT_UNKNOWN 0 601 #define GOT_NORMAL 1 602 #define GOT_TLS_GD 2 603 #define GOT_TLS_IE 4 604 #define GOT_TLS_IE_POS 5 605 #define GOT_TLS_IE_NEG 6 606 #define GOT_TLS_IE_BOTH 7 607 #define GOT_TLS_GDESC 8 608 #define GOT_TLS_GD_BOTH_P(type) \ 609 ((type) == (GOT_TLS_GD | GOT_TLS_GDESC)) 610 #define GOT_TLS_GD_P(type) \ 611 ((type) == GOT_TLS_GD || GOT_TLS_GD_BOTH_P (type)) 612 #define GOT_TLS_GDESC_P(type) \ 613 ((type) == GOT_TLS_GDESC || GOT_TLS_GD_BOTH_P (type)) 614 #define GOT_TLS_GD_ANY_P(type) \ 615 (GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type)) 616 unsigned char tls_type; 617 618 /* Offset of the GOTPLT entry reserved for the TLS descriptor, 619 starting at the end of the jump table. */ 620 bfd_vma tlsdesc_got; 621 }; 622 623 #define elf_i386_hash_entry(ent) ((struct elf_i386_link_hash_entry *)(ent)) 624 625 struct elf_i386_obj_tdata 626 { 627 struct elf_obj_tdata root; 628 629 /* tls_type for each local got entry. */ 630 char *local_got_tls_type; 631 632 /* GOTPLT entries for TLS descriptors. */ 633 bfd_vma *local_tlsdesc_gotent; 634 }; 635 636 #define elf_i386_tdata(abfd) \ 637 ((struct elf_i386_obj_tdata *) (abfd)->tdata.any) 638 639 #define elf_i386_local_got_tls_type(abfd) \ 640 (elf_i386_tdata (abfd)->local_got_tls_type) 641 642 #define elf_i386_local_tlsdesc_gotent(abfd) \ 643 (elf_i386_tdata (abfd)->local_tlsdesc_gotent) 644 645 #define is_i386_elf(bfd) \ 646 (bfd_get_flavour (bfd) == bfd_target_elf_flavour \ 647 && elf_tdata (bfd) != NULL \ 648 && elf_object_id (bfd) == I386_ELF_TDATA) 649 650 static bfd_boolean 651 elf_i386_mkobject (bfd *abfd) 652 { 653 return bfd_elf_allocate_object (abfd, sizeof (struct elf_i386_obj_tdata), 654 I386_ELF_TDATA); 655 } 656 657 /* i386 ELF linker hash table. */ 658 659 struct elf_i386_link_hash_table 660 { 661 struct elf_link_hash_table elf; 662 663 /* Short-cuts to get to dynamic linker sections. */ 664 asection *sgot; 665 asection *sgotplt; 666 asection *srelgot; 667 asection *splt; 668 asection *srelplt; 669 asection *sdynbss; 670 asection *srelbss; 671 672 /* The (unloaded but important) .rel.plt.unloaded section on VxWorks. */ 673 asection *srelplt2; 674 675 /* True if the target system is VxWorks. */ 676 int is_vxworks; 677 678 /* Value used to fill the last word of the first plt entry. */ 679 bfd_byte plt0_pad_byte; 680 681 /* The index of the next unused R_386_TLS_DESC slot in .rel.plt. */ 682 bfd_vma next_tls_desc_index; 683 684 union { 685 bfd_signed_vma refcount; 686 bfd_vma offset; 687 } tls_ldm_got; 688 689 /* The amount of space used by the reserved portion of the sgotplt 690 section, plus whatever space is used by the jump slots. */ 691 bfd_vma sgotplt_jump_table_size; 692 693 /* Small local sym to section mapping cache. */ 694 struct sym_sec_cache sym_sec; 695 696 /* _TLS_MODULE_BASE_ symbol. */ 697 struct bfd_link_hash_entry *tls_module_base; 698 }; 699 700 /* Get the i386 ELF linker hash table from a link_info structure. */ 701 702 #define elf_i386_hash_table(p) \ 703 ((struct elf_i386_link_hash_table *) ((p)->hash)) 704 705 #define elf_i386_compute_jump_table_size(htab) \ 706 ((htab)->next_tls_desc_index * 4) 707 708 /* Create an entry in an i386 ELF linker hash table. */ 709 710 static struct bfd_hash_entry * 711 link_hash_newfunc (struct bfd_hash_entry *entry, 712 struct bfd_hash_table *table, 713 const char *string) 714 { 715 /* Allocate the structure if it has not already been allocated by a 716 subclass. */ 717 if (entry == NULL) 718 { 719 entry = bfd_hash_allocate (table, 720 sizeof (struct elf_i386_link_hash_entry)); 721 if (entry == NULL) 722 return entry; 723 } 724 725 /* Call the allocation method of the superclass. */ 726 entry = _bfd_elf_link_hash_newfunc (entry, table, string); 727 if (entry != NULL) 728 { 729 struct elf_i386_link_hash_entry *eh; 730 731 eh = (struct elf_i386_link_hash_entry *) entry; 732 eh->dyn_relocs = NULL; 733 eh->tls_type = GOT_UNKNOWN; 734 eh->tlsdesc_got = (bfd_vma) -1; 735 } 736 737 return entry; 738 } 739 740 /* Create an i386 ELF linker hash table. */ 741 742 static struct bfd_link_hash_table * 743 elf_i386_link_hash_table_create (bfd *abfd) 744 { 745 struct elf_i386_link_hash_table *ret; 746 bfd_size_type amt = sizeof (struct elf_i386_link_hash_table); 747 748 ret = bfd_malloc (amt); 749 if (ret == NULL) 750 return NULL; 751 752 if (!_bfd_elf_link_hash_table_init (&ret->elf, abfd, link_hash_newfunc, 753 sizeof (struct elf_i386_link_hash_entry))) 754 { 755 free (ret); 756 return NULL; 757 } 758 759 ret->sgot = NULL; 760 ret->sgotplt = NULL; 761 ret->srelgot = NULL; 762 ret->splt = NULL; 763 ret->srelplt = NULL; 764 ret->sdynbss = NULL; 765 ret->srelbss = NULL; 766 ret->tls_ldm_got.refcount = 0; 767 ret->next_tls_desc_index = 0; 768 ret->sgotplt_jump_table_size = 0; 769 ret->sym_sec.abfd = NULL; 770 ret->is_vxworks = 0; 771 ret->srelplt2 = NULL; 772 ret->plt0_pad_byte = 0; 773 ret->tls_module_base = NULL; 774 775 return &ret->elf.root; 776 } 777 778 /* Create .got, .gotplt, and .rel.got sections in DYNOBJ, and set up 779 shortcuts to them in our hash table. */ 780 781 static bfd_boolean 782 create_got_section (bfd *dynobj, struct bfd_link_info *info) 783 { 784 struct elf_i386_link_hash_table *htab; 785 786 if (! _bfd_elf_create_got_section (dynobj, info)) 787 return FALSE; 788 789 htab = elf_i386_hash_table (info); 790 htab->sgot = bfd_get_section_by_name (dynobj, ".got"); 791 htab->sgotplt = bfd_get_section_by_name (dynobj, ".got.plt"); 792 if (!htab->sgot || !htab->sgotplt) 793 abort (); 794 795 htab->srelgot = bfd_make_section_with_flags (dynobj, ".rel.got", 796 (SEC_ALLOC | SEC_LOAD 797 | SEC_HAS_CONTENTS 798 | SEC_IN_MEMORY 799 | SEC_LINKER_CREATED 800 | SEC_READONLY)); 801 if (htab->srelgot == NULL 802 || ! bfd_set_section_alignment (dynobj, htab->srelgot, 2)) 803 return FALSE; 804 return TRUE; 805 } 806 807 /* Create .plt, .rel.plt, .got, .got.plt, .rel.got, .dynbss, and 808 .rel.bss sections in DYNOBJ, and set up shortcuts to them in our 809 hash table. */ 810 811 static bfd_boolean 812 elf_i386_create_dynamic_sections (bfd *dynobj, struct bfd_link_info *info) 813 { 814 struct elf_i386_link_hash_table *htab; 815 816 htab = elf_i386_hash_table (info); 817 if (!htab->sgot && !create_got_section (dynobj, info)) 818 return FALSE; 819 820 if (!_bfd_elf_create_dynamic_sections (dynobj, info)) 821 return FALSE; 822 823 htab->splt = bfd_get_section_by_name (dynobj, ".plt"); 824 htab->srelplt = bfd_get_section_by_name (dynobj, ".rel.plt"); 825 htab->sdynbss = bfd_get_section_by_name (dynobj, ".dynbss"); 826 if (!info->shared) 827 htab->srelbss = bfd_get_section_by_name (dynobj, ".rel.bss"); 828 829 if (!htab->splt || !htab->srelplt || !htab->sdynbss 830 || (!info->shared && !htab->srelbss)) 831 abort (); 832 833 if (htab->is_vxworks 834 && !elf_vxworks_create_dynamic_sections (dynobj, info, &htab->srelplt2)) 835 return FALSE; 836 837 return TRUE; 838 } 839 840 /* Copy the extra info we tack onto an elf_link_hash_entry. */ 841 842 static void 843 elf_i386_copy_indirect_symbol (struct bfd_link_info *info, 844 struct elf_link_hash_entry *dir, 845 struct elf_link_hash_entry *ind) 846 { 847 struct elf_i386_link_hash_entry *edir, *eind; 848 849 edir = (struct elf_i386_link_hash_entry *) dir; 850 eind = (struct elf_i386_link_hash_entry *) ind; 851 852 if (eind->dyn_relocs != NULL) 853 { 854 if (edir->dyn_relocs != NULL) 855 { 856 struct elf_i386_dyn_relocs **pp; 857 struct elf_i386_dyn_relocs *p; 858 859 /* Add reloc counts against the indirect sym to the direct sym 860 list. Merge any entries against the same section. */ 861 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; ) 862 { 863 struct elf_i386_dyn_relocs *q; 864 865 for (q = edir->dyn_relocs; q != NULL; q = q->next) 866 if (q->sec == p->sec) 867 { 868 q->pc_count += p->pc_count; 869 q->count += p->count; 870 *pp = p->next; 871 break; 872 } 873 if (q == NULL) 874 pp = &p->next; 875 } 876 *pp = edir->dyn_relocs; 877 } 878 879 edir->dyn_relocs = eind->dyn_relocs; 880 eind->dyn_relocs = NULL; 881 } 882 883 if (ind->root.type == bfd_link_hash_indirect 884 && dir->got.refcount <= 0) 885 { 886 edir->tls_type = eind->tls_type; 887 eind->tls_type = GOT_UNKNOWN; 888 } 889 890 if (ELIMINATE_COPY_RELOCS 891 && ind->root.type != bfd_link_hash_indirect 892 && dir->dynamic_adjusted) 893 { 894 /* If called to transfer flags for a weakdef during processing 895 of elf_adjust_dynamic_symbol, don't copy non_got_ref. 896 We clear it ourselves for ELIMINATE_COPY_RELOCS. */ 897 dir->ref_dynamic |= ind->ref_dynamic; 898 dir->ref_regular |= ind->ref_regular; 899 dir->ref_regular_nonweak |= ind->ref_regular_nonweak; 900 dir->needs_plt |= ind->needs_plt; 901 dir->pointer_equality_needed |= ind->pointer_equality_needed; 902 } 903 else 904 _bfd_elf_link_hash_copy_indirect (info, dir, ind); 905 } 906 907 typedef union 908 { 909 unsigned char c[2]; 910 uint16_t i; 911 } 912 i386_opcode16; 913 914 /* Return TRUE if the TLS access code sequence support transition 915 from R_TYPE. */ 916 917 static bfd_boolean 918 elf_i386_check_tls_transition (bfd *abfd, asection *sec, 919 bfd_byte *contents, 920 Elf_Internal_Shdr *symtab_hdr, 921 struct elf_link_hash_entry **sym_hashes, 922 unsigned int r_type, 923 const Elf_Internal_Rela *rel, 924 const Elf_Internal_Rela *relend) 925 { 926 unsigned int val, type; 927 unsigned long r_symndx; 928 struct elf_link_hash_entry *h; 929 bfd_vma offset; 930 931 /* Get the section contents. */ 932 if (contents == NULL) 933 { 934 if (elf_section_data (sec)->this_hdr.contents != NULL) 935 contents = elf_section_data (sec)->this_hdr.contents; 936 else 937 { 938 /* FIXME: How to better handle error condition? */ 939 if (!bfd_malloc_and_get_section (abfd, sec, &contents)) 940 return FALSE; 941 942 /* Cache the section contents for elf_link_input_bfd. */ 943 elf_section_data (sec)->this_hdr.contents = contents; 944 } 945 } 946 947 offset = rel->r_offset; 948 switch (r_type) 949 { 950 case R_386_TLS_GD: 951 case R_386_TLS_LDM: 952 if (offset < 2 || (rel + 1) >= relend) 953 return FALSE; 954 955 type = bfd_get_8 (abfd, contents + offset - 2); 956 if (r_type == R_386_TLS_GD) 957 { 958 /* Check transition from LD access model. Only 959 leal foo@tlsgd(,%reg,1), %eax; call ___tls_get_addr 960 leal foo@tlsgd(%reg), %eax; call ___tls_get_addr; nop 961 can transit to different access model. */ 962 if ((offset + 10) > sec->size || 963 (type != 0x8d && type != 0x04)) 964 return FALSE; 965 966 val = bfd_get_8 (abfd, contents + offset - 1); 967 if (type == 0x04) 968 { 969 /* leal foo@tlsgd(,%reg,1), %eax; call ___tls_get_addr */ 970 if (offset < 3) 971 return FALSE; 972 973 if (bfd_get_8 (abfd, contents + offset - 3) != 0x8d) 974 return FALSE; 975 976 if ((val & 0xc7) != 0x05 || val == (4 << 3)) 977 return FALSE; 978 } 979 else 980 { 981 /* leal foo@tlsgd(%reg), %eax; call ___tls_get_addr; nop */ 982 if ((val & 0xf8) != 0x80 || (val & 7) == 4) 983 return FALSE; 984 985 if (bfd_get_8 (abfd, contents + offset + 9) != 0x90) 986 return FALSE; 987 } 988 } 989 else 990 { 991 /* Check transition from LD access model. Only 992 leal foo@tlsgd(%reg), %eax; call ___tls_get_addr 993 can transit to different access model. */ 994 if (type != 0x8d || (offset + 9) > sec->size) 995 return FALSE; 996 997 val = bfd_get_8 (abfd, contents + offset - 1); 998 if ((val & 0xf8) != 0x80 || (val & 7) == 4) 999 return FALSE; 1000 } 1001 1002 if (bfd_get_8 (abfd, contents + offset + 4) != 0xe8) 1003 return FALSE; 1004 1005 r_symndx = ELF32_R_SYM (rel[1].r_info); 1006 if (r_symndx < symtab_hdr->sh_info) 1007 return FALSE; 1008 1009 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 1010 return (h != NULL 1011 && h->root.root.string != NULL 1012 && (ELF32_R_TYPE (rel[1].r_info) == R_386_PC32 1013 || ELF32_R_TYPE (rel[1].r_info) == R_386_PLT32) 1014 && (strcmp (h->root.root.string, "___tls_get_addr") == 0)); 1015 1016 case R_386_TLS_IE: 1017 /* Check transition from IE access model: 1018 movl foo@indntpoff(%rip), %eax 1019 movl foo@indntpoff(%rip), %reg 1020 addl foo@indntpoff(%rip), %reg 1021 */ 1022 1023 if (offset < 1 || (offset + 4) > sec->size) 1024 return FALSE; 1025 1026 /* Check "movl foo@tpoff(%rip), %eax" first. */ 1027 val = bfd_get_8 (abfd, contents + offset - 1); 1028 if (val == 0xa1) 1029 return TRUE; 1030 1031 if (offset < 2) 1032 return FALSE; 1033 1034 /* Check movl|addl foo@tpoff(%rip), %reg. */ 1035 type = bfd_get_8 (abfd, contents + offset - 2); 1036 return ((type == 0x8b || type == 0x03) 1037 && (val & 0xc7) == 0x05); 1038 1039 case R_386_TLS_GOTIE: 1040 case R_386_TLS_IE_32: 1041 /* Check transition from {IE_32,GOTIE} access model: 1042 subl foo@{tpoff,gontoff}(%reg1), %reg2 1043 movl foo@{tpoff,gontoff}(%reg1), %reg2 1044 addl foo@{tpoff,gontoff}(%reg1), %reg2 1045 */ 1046 1047 if (offset < 2 || (offset + 4) > sec->size) 1048 return FALSE; 1049 1050 val = bfd_get_8 (abfd, contents + offset - 1); 1051 if ((val & 0xc0) != 0x80 || (val & 7) == 4) 1052 return FALSE; 1053 1054 type = bfd_get_8 (abfd, contents + offset - 2); 1055 return type == 0x8b || type == 0x2b || type == 0x03; 1056 1057 case R_386_TLS_GOTDESC: 1058 /* Check transition from GDesc access model: 1059 leal x@tlsdesc(%ebx), %eax 1060 1061 Make sure it's a leal adding ebx to a 32-bit offset 1062 into any register, although it's probably almost always 1063 going to be eax. */ 1064 1065 if (offset < 2 || (offset + 4) > sec->size) 1066 return FALSE; 1067 1068 if (bfd_get_8 (abfd, contents + offset - 2) != 0x8d) 1069 return FALSE; 1070 1071 val = bfd_get_8 (abfd, contents + offset - 1); 1072 return (val & 0xc7) == 0x83; 1073 1074 case R_386_TLS_DESC_CALL: 1075 /* Check transition from GDesc access model: 1076 call *x@tlsdesc(%rax) 1077 */ 1078 if (offset + 2 <= sec->size) 1079 { 1080 /* Make sure that it's a call *x@tlsdesc(%rax). */ 1081 static i386_opcode16 call = { { 0xff, 0x10 } }; 1082 return bfd_get_16 (abfd, contents + offset) == call.i; 1083 } 1084 1085 return FALSE; 1086 1087 default: 1088 abort (); 1089 } 1090 } 1091 1092 /* Return TRUE if the TLS access transition is OK or no transition 1093 will be performed. Update R_TYPE if there is a transition. */ 1094 1095 static bfd_boolean 1096 elf_i386_tls_transition (struct bfd_link_info *info, bfd *abfd, 1097 asection *sec, bfd_byte *contents, 1098 Elf_Internal_Shdr *symtab_hdr, 1099 struct elf_link_hash_entry **sym_hashes, 1100 unsigned int *r_type, int tls_type, 1101 const Elf_Internal_Rela *rel, 1102 const Elf_Internal_Rela *relend, 1103 struct elf_link_hash_entry *h) 1104 { 1105 unsigned int from_type = *r_type; 1106 unsigned int to_type = from_type; 1107 bfd_boolean check = TRUE; 1108 1109 switch (from_type) 1110 { 1111 case R_386_TLS_GD: 1112 case R_386_TLS_GOTDESC: 1113 case R_386_TLS_DESC_CALL: 1114 case R_386_TLS_IE_32: 1115 case R_386_TLS_IE: 1116 case R_386_TLS_GOTIE: 1117 if (!info->shared) 1118 { 1119 if (h == NULL) 1120 to_type = R_386_TLS_LE_32; 1121 else if (from_type != R_386_TLS_IE 1122 && from_type != R_386_TLS_GOTIE) 1123 to_type = R_386_TLS_IE_32; 1124 } 1125 1126 /* When we are called from elf_i386_relocate_section, CONTENTS 1127 isn't NULL and there may be additional transitions based on 1128 TLS_TYPE. */ 1129 if (contents != NULL) 1130 { 1131 unsigned int new_to_type = to_type; 1132 1133 if (!info->shared 1134 && h != NULL 1135 && h->dynindx == -1 1136 && (tls_type & GOT_TLS_IE)) 1137 new_to_type = R_386_TLS_LE_32; 1138 1139 if (to_type == R_386_TLS_GD 1140 || to_type == R_386_TLS_GOTDESC 1141 || to_type == R_386_TLS_DESC_CALL) 1142 { 1143 if (tls_type == GOT_TLS_IE_POS) 1144 new_to_type = R_386_TLS_GOTIE; 1145 else if (tls_type & GOT_TLS_IE) 1146 new_to_type = R_386_TLS_IE_32; 1147 } 1148 1149 /* We checked the transition before when we were called from 1150 elf_i386_check_relocs. We only want to check the new 1151 transition which hasn't been checked before. */ 1152 check = new_to_type != to_type && from_type == to_type; 1153 to_type = new_to_type; 1154 } 1155 1156 break; 1157 1158 case R_386_TLS_LDM: 1159 if (!info->shared) 1160 to_type = R_386_TLS_LE_32; 1161 break; 1162 1163 default: 1164 return TRUE; 1165 } 1166 1167 /* Return TRUE if there is no transition. */ 1168 if (from_type == to_type) 1169 return TRUE; 1170 1171 /* Check if the transition can be performed. */ 1172 if (check 1173 && ! elf_i386_check_tls_transition (abfd, sec, contents, 1174 symtab_hdr, sym_hashes, 1175 from_type, rel, relend)) 1176 { 1177 reloc_howto_type *from, *to; 1178 1179 from = elf_i386_rtype_to_howto (abfd, from_type); 1180 to = elf_i386_rtype_to_howto (abfd, to_type); 1181 1182 (*_bfd_error_handler) 1183 (_("%B: TLS transition from %s to %s against `%s' at 0x%lx " 1184 "in section `%A' failed"), 1185 abfd, sec, from->name, to->name, 1186 h ? h->root.root.string : "a local symbol", 1187 (unsigned long) rel->r_offset); 1188 bfd_set_error (bfd_error_bad_value); 1189 return FALSE; 1190 } 1191 1192 *r_type = to_type; 1193 return TRUE; 1194 } 1195 1196 /* Look through the relocs for a section during the first phase, and 1197 calculate needed space in the global offset table, procedure linkage 1198 table, and dynamic reloc sections. */ 1199 1200 static bfd_boolean 1201 elf_i386_check_relocs (bfd *abfd, 1202 struct bfd_link_info *info, 1203 asection *sec, 1204 const Elf_Internal_Rela *relocs) 1205 { 1206 struct elf_i386_link_hash_table *htab; 1207 Elf_Internal_Shdr *symtab_hdr; 1208 struct elf_link_hash_entry **sym_hashes; 1209 const Elf_Internal_Rela *rel; 1210 const Elf_Internal_Rela *rel_end; 1211 asection *sreloc; 1212 1213 if (info->relocatable) 1214 return TRUE; 1215 1216 BFD_ASSERT (is_i386_elf (abfd)); 1217 1218 htab = elf_i386_hash_table (info); 1219 symtab_hdr = &elf_symtab_hdr (abfd); 1220 sym_hashes = elf_sym_hashes (abfd); 1221 1222 sreloc = NULL; 1223 1224 rel_end = relocs + sec->reloc_count; 1225 for (rel = relocs; rel < rel_end; rel++) 1226 { 1227 unsigned int r_type; 1228 unsigned long r_symndx; 1229 struct elf_link_hash_entry *h; 1230 1231 r_symndx = ELF32_R_SYM (rel->r_info); 1232 r_type = ELF32_R_TYPE (rel->r_info); 1233 1234 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr)) 1235 { 1236 (*_bfd_error_handler) (_("%B: bad symbol index: %d"), 1237 abfd, 1238 r_symndx); 1239 return FALSE; 1240 } 1241 1242 if (r_symndx < symtab_hdr->sh_info) 1243 h = NULL; 1244 else 1245 { 1246 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 1247 while (h->root.type == bfd_link_hash_indirect 1248 || h->root.type == bfd_link_hash_warning) 1249 h = (struct elf_link_hash_entry *) h->root.u.i.link; 1250 } 1251 1252 if (! elf_i386_tls_transition (info, abfd, sec, NULL, 1253 symtab_hdr, sym_hashes, 1254 &r_type, GOT_UNKNOWN, 1255 rel, rel_end, h)) 1256 return FALSE; 1257 1258 switch (r_type) 1259 { 1260 case R_386_TLS_LDM: 1261 htab->tls_ldm_got.refcount += 1; 1262 goto create_got; 1263 1264 case R_386_PLT32: 1265 /* This symbol requires a procedure linkage table entry. We 1266 actually build the entry in adjust_dynamic_symbol, 1267 because this might be a case of linking PIC code which is 1268 never referenced by a dynamic object, in which case we 1269 don't need to generate a procedure linkage table entry 1270 after all. */ 1271 1272 /* If this is a local symbol, we resolve it directly without 1273 creating a procedure linkage table entry. */ 1274 if (h == NULL) 1275 continue; 1276 1277 h->needs_plt = 1; 1278 h->plt.refcount += 1; 1279 break; 1280 1281 case R_386_TLS_IE_32: 1282 case R_386_TLS_IE: 1283 case R_386_TLS_GOTIE: 1284 if (info->shared) 1285 info->flags |= DF_STATIC_TLS; 1286 /* Fall through */ 1287 1288 case R_386_GOT32: 1289 case R_386_TLS_GD: 1290 case R_386_TLS_GOTDESC: 1291 case R_386_TLS_DESC_CALL: 1292 /* This symbol requires a global offset table entry. */ 1293 { 1294 int tls_type, old_tls_type; 1295 1296 switch (r_type) 1297 { 1298 default: 1299 case R_386_GOT32: tls_type = GOT_NORMAL; break; 1300 case R_386_TLS_GD: tls_type = GOT_TLS_GD; break; 1301 case R_386_TLS_GOTDESC: 1302 case R_386_TLS_DESC_CALL: 1303 tls_type = GOT_TLS_GDESC; break; 1304 case R_386_TLS_IE_32: 1305 if (ELF32_R_TYPE (rel->r_info) == r_type) 1306 tls_type = GOT_TLS_IE_NEG; 1307 else 1308 /* If this is a GD->IE transition, we may use either of 1309 R_386_TLS_TPOFF and R_386_TLS_TPOFF32. */ 1310 tls_type = GOT_TLS_IE; 1311 break; 1312 case R_386_TLS_IE: 1313 case R_386_TLS_GOTIE: 1314 tls_type = GOT_TLS_IE_POS; break; 1315 } 1316 1317 if (h != NULL) 1318 { 1319 h->got.refcount += 1; 1320 old_tls_type = elf_i386_hash_entry(h)->tls_type; 1321 } 1322 else 1323 { 1324 bfd_signed_vma *local_got_refcounts; 1325 1326 /* This is a global offset table entry for a local symbol. */ 1327 local_got_refcounts = elf_local_got_refcounts (abfd); 1328 if (local_got_refcounts == NULL) 1329 { 1330 bfd_size_type size; 1331 1332 size = symtab_hdr->sh_info; 1333 size *= (sizeof (bfd_signed_vma) 1334 + sizeof (bfd_vma) + sizeof(char)); 1335 local_got_refcounts = bfd_zalloc (abfd, size); 1336 if (local_got_refcounts == NULL) 1337 return FALSE; 1338 elf_local_got_refcounts (abfd) = local_got_refcounts; 1339 elf_i386_local_tlsdesc_gotent (abfd) 1340 = (bfd_vma *) (local_got_refcounts + symtab_hdr->sh_info); 1341 elf_i386_local_got_tls_type (abfd) 1342 = (char *) (local_got_refcounts + 2 * symtab_hdr->sh_info); 1343 } 1344 local_got_refcounts[r_symndx] += 1; 1345 old_tls_type = elf_i386_local_got_tls_type (abfd) [r_symndx]; 1346 } 1347 1348 if ((old_tls_type & GOT_TLS_IE) && (tls_type & GOT_TLS_IE)) 1349 tls_type |= old_tls_type; 1350 /* If a TLS symbol is accessed using IE at least once, 1351 there is no point to use dynamic model for it. */ 1352 else if (old_tls_type != tls_type && old_tls_type != GOT_UNKNOWN 1353 && (! GOT_TLS_GD_ANY_P (old_tls_type) 1354 || (tls_type & GOT_TLS_IE) == 0)) 1355 { 1356 if ((old_tls_type & GOT_TLS_IE) && GOT_TLS_GD_ANY_P (tls_type)) 1357 tls_type = old_tls_type; 1358 else if (GOT_TLS_GD_ANY_P (old_tls_type) 1359 && GOT_TLS_GD_ANY_P (tls_type)) 1360 tls_type |= old_tls_type; 1361 else 1362 { 1363 (*_bfd_error_handler) 1364 (_("%B: `%s' accessed both as normal and " 1365 "thread local symbol"), 1366 abfd, 1367 h ? h->root.root.string : "<local>"); 1368 return FALSE; 1369 } 1370 } 1371 1372 if (old_tls_type != tls_type) 1373 { 1374 if (h != NULL) 1375 elf_i386_hash_entry (h)->tls_type = tls_type; 1376 else 1377 elf_i386_local_got_tls_type (abfd) [r_symndx] = tls_type; 1378 } 1379 } 1380 /* Fall through */ 1381 1382 case R_386_GOTOFF: 1383 case R_386_GOTPC: 1384 create_got: 1385 if (htab->sgot == NULL) 1386 { 1387 if (htab->elf.dynobj == NULL) 1388 htab->elf.dynobj = abfd; 1389 if (!create_got_section (htab->elf.dynobj, info)) 1390 return FALSE; 1391 } 1392 if (r_type != R_386_TLS_IE) 1393 break; 1394 /* Fall through */ 1395 1396 case R_386_TLS_LE_32: 1397 case R_386_TLS_LE: 1398 if (!info->shared) 1399 break; 1400 info->flags |= DF_STATIC_TLS; 1401 /* Fall through */ 1402 1403 case R_386_32: 1404 case R_386_PC32: 1405 if (h != NULL && !info->shared) 1406 { 1407 /* If this reloc is in a read-only section, we might 1408 need a copy reloc. We can't check reliably at this 1409 stage whether the section is read-only, as input 1410 sections have not yet been mapped to output sections. 1411 Tentatively set the flag for now, and correct in 1412 adjust_dynamic_symbol. */ 1413 h->non_got_ref = 1; 1414 1415 /* We may need a .plt entry if the function this reloc 1416 refers to is in a shared lib. */ 1417 h->plt.refcount += 1; 1418 if (r_type != R_386_PC32) 1419 h->pointer_equality_needed = 1; 1420 } 1421 1422 /* If we are creating a shared library, and this is a reloc 1423 against a global symbol, or a non PC relative reloc 1424 against a local symbol, then we need to copy the reloc 1425 into the shared library. However, if we are linking with 1426 -Bsymbolic, we do not need to copy a reloc against a 1427 global symbol which is defined in an object we are 1428 including in the link (i.e., DEF_REGULAR is set). At 1429 this point we have not seen all the input files, so it is 1430 possible that DEF_REGULAR is not set now but will be set 1431 later (it is never cleared). In case of a weak definition, 1432 DEF_REGULAR may be cleared later by a strong definition in 1433 a shared library. We account for that possibility below by 1434 storing information in the relocs_copied field of the hash 1435 table entry. A similar situation occurs when creating 1436 shared libraries and symbol visibility changes render the 1437 symbol local. 1438 1439 If on the other hand, we are creating an executable, we 1440 may need to keep relocations for symbols satisfied by a 1441 dynamic library if we manage to avoid copy relocs for the 1442 symbol. */ 1443 if ((info->shared 1444 && (sec->flags & SEC_ALLOC) != 0 1445 && (r_type != R_386_PC32 1446 || (h != NULL 1447 && (! SYMBOLIC_BIND (info, h) 1448 || h->root.type == bfd_link_hash_defweak 1449 || !h->def_regular)))) 1450 || (ELIMINATE_COPY_RELOCS 1451 && !info->shared 1452 && (sec->flags & SEC_ALLOC) != 0 1453 && h != NULL 1454 && (h->root.type == bfd_link_hash_defweak 1455 || !h->def_regular))) 1456 { 1457 struct elf_i386_dyn_relocs *p; 1458 struct elf_i386_dyn_relocs **head; 1459 1460 /* We must copy these reloc types into the output file. 1461 Create a reloc section in dynobj and make room for 1462 this reloc. */ 1463 if (sreloc == NULL) 1464 { 1465 const char *name; 1466 bfd *dynobj; 1467 unsigned int strndx = elf_elfheader (abfd)->e_shstrndx; 1468 unsigned int shnam = elf_section_data (sec)->rel_hdr.sh_name; 1469 1470 name = bfd_elf_string_from_elf_section (abfd, strndx, shnam); 1471 if (name == NULL) 1472 return FALSE; 1473 1474 if (! CONST_STRNEQ (name, ".rel") 1475 || strcmp (bfd_get_section_name (abfd, sec), 1476 name + 4) != 0) 1477 { 1478 (*_bfd_error_handler) 1479 (_("%B: bad relocation section name `%s\'"), 1480 abfd, name); 1481 } 1482 1483 if (htab->elf.dynobj == NULL) 1484 htab->elf.dynobj = abfd; 1485 1486 dynobj = htab->elf.dynobj; 1487 sreloc = bfd_get_section_by_name (dynobj, name); 1488 if (sreloc == NULL) 1489 { 1490 flagword flags; 1491 1492 flags = (SEC_HAS_CONTENTS | SEC_READONLY 1493 | SEC_IN_MEMORY | SEC_LINKER_CREATED); 1494 if ((sec->flags & SEC_ALLOC) != 0) 1495 flags |= SEC_ALLOC | SEC_LOAD; 1496 sreloc = bfd_make_section_with_flags (dynobj, 1497 name, 1498 flags); 1499 if (sreloc == NULL 1500 || ! bfd_set_section_alignment (dynobj, sreloc, 2)) 1501 return FALSE; 1502 } 1503 elf_section_data (sec)->sreloc = sreloc; 1504 } 1505 1506 /* If this is a global symbol, we count the number of 1507 relocations we need for this symbol. */ 1508 if (h != NULL) 1509 { 1510 head = &((struct elf_i386_link_hash_entry *) h)->dyn_relocs; 1511 } 1512 else 1513 { 1514 void **vpp; 1515 /* Track dynamic relocs needed for local syms too. 1516 We really need local syms available to do this 1517 easily. Oh well. */ 1518 1519 asection *s; 1520 s = bfd_section_from_r_symndx (abfd, &htab->sym_sec, 1521 sec, r_symndx); 1522 if (s == NULL) 1523 return FALSE; 1524 1525 vpp = &elf_section_data (s)->local_dynrel; 1526 head = (struct elf_i386_dyn_relocs **)vpp; 1527 } 1528 1529 p = *head; 1530 if (p == NULL || p->sec != sec) 1531 { 1532 bfd_size_type amt = sizeof *p; 1533 p = bfd_alloc (htab->elf.dynobj, amt); 1534 if (p == NULL) 1535 return FALSE; 1536 p->next = *head; 1537 *head = p; 1538 p->sec = sec; 1539 p->count = 0; 1540 p->pc_count = 0; 1541 } 1542 1543 p->count += 1; 1544 if (r_type == R_386_PC32) 1545 p->pc_count += 1; 1546 } 1547 break; 1548 1549 /* This relocation describes the C++ object vtable hierarchy. 1550 Reconstruct it for later use during GC. */ 1551 case R_386_GNU_VTINHERIT: 1552 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset)) 1553 return FALSE; 1554 break; 1555 1556 /* This relocation describes which C++ vtable entries are actually 1557 used. Record for later use during GC. */ 1558 case R_386_GNU_VTENTRY: 1559 BFD_ASSERT (h != NULL); 1560 if (h != NULL 1561 && !bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_offset)) 1562 return FALSE; 1563 break; 1564 1565 default: 1566 break; 1567 } 1568 } 1569 1570 return TRUE; 1571 } 1572 1573 /* Return the section that should be marked against GC for a given 1574 relocation. */ 1575 1576 static asection * 1577 elf_i386_gc_mark_hook (asection *sec, 1578 struct bfd_link_info *info, 1579 Elf_Internal_Rela *rel, 1580 struct elf_link_hash_entry *h, 1581 Elf_Internal_Sym *sym) 1582 { 1583 if (h != NULL) 1584 switch (ELF32_R_TYPE (rel->r_info)) 1585 { 1586 case R_386_GNU_VTINHERIT: 1587 case R_386_GNU_VTENTRY: 1588 return NULL; 1589 } 1590 1591 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym); 1592 } 1593 1594 /* Update the got entry reference counts for the section being removed. */ 1595 1596 static bfd_boolean 1597 elf_i386_gc_sweep_hook (bfd *abfd, 1598 struct bfd_link_info *info, 1599 asection *sec, 1600 const Elf_Internal_Rela *relocs) 1601 { 1602 Elf_Internal_Shdr *symtab_hdr; 1603 struct elf_link_hash_entry **sym_hashes; 1604 bfd_signed_vma *local_got_refcounts; 1605 const Elf_Internal_Rela *rel, *relend; 1606 1607 if (info->relocatable) 1608 return TRUE; 1609 1610 elf_section_data (sec)->local_dynrel = NULL; 1611 1612 symtab_hdr = &elf_symtab_hdr (abfd); 1613 sym_hashes = elf_sym_hashes (abfd); 1614 local_got_refcounts = elf_local_got_refcounts (abfd); 1615 1616 relend = relocs + sec->reloc_count; 1617 for (rel = relocs; rel < relend; rel++) 1618 { 1619 unsigned long r_symndx; 1620 unsigned int r_type; 1621 struct elf_link_hash_entry *h = NULL; 1622 1623 r_symndx = ELF32_R_SYM (rel->r_info); 1624 if (r_symndx >= symtab_hdr->sh_info) 1625 { 1626 struct elf_i386_link_hash_entry *eh; 1627 struct elf_i386_dyn_relocs **pp; 1628 struct elf_i386_dyn_relocs *p; 1629 1630 h = sym_hashes[r_symndx - symtab_hdr->sh_info]; 1631 while (h->root.type == bfd_link_hash_indirect 1632 || h->root.type == bfd_link_hash_warning) 1633 h = (struct elf_link_hash_entry *) h->root.u.i.link; 1634 eh = (struct elf_i386_link_hash_entry *) h; 1635 1636 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next) 1637 if (p->sec == sec) 1638 { 1639 /* Everything must go for SEC. */ 1640 *pp = p->next; 1641 break; 1642 } 1643 } 1644 1645 r_type = ELF32_R_TYPE (rel->r_info); 1646 if (! elf_i386_tls_transition (info, abfd, sec, NULL, 1647 symtab_hdr, sym_hashes, 1648 &r_type, GOT_UNKNOWN, 1649 rel, relend, h)) 1650 return FALSE; 1651 1652 switch (r_type) 1653 { 1654 case R_386_TLS_LDM: 1655 if (elf_i386_hash_table (info)->tls_ldm_got.refcount > 0) 1656 elf_i386_hash_table (info)->tls_ldm_got.refcount -= 1; 1657 break; 1658 1659 case R_386_TLS_GD: 1660 case R_386_TLS_GOTDESC: 1661 case R_386_TLS_DESC_CALL: 1662 case R_386_TLS_IE_32: 1663 case R_386_TLS_IE: 1664 case R_386_TLS_GOTIE: 1665 case R_386_GOT32: 1666 if (h != NULL) 1667 { 1668 if (h->got.refcount > 0) 1669 h->got.refcount -= 1; 1670 } 1671 else if (local_got_refcounts != NULL) 1672 { 1673 if (local_got_refcounts[r_symndx] > 0) 1674 local_got_refcounts[r_symndx] -= 1; 1675 } 1676 break; 1677 1678 case R_386_32: 1679 case R_386_PC32: 1680 if (info->shared) 1681 break; 1682 /* Fall through */ 1683 1684 case R_386_PLT32: 1685 if (h != NULL) 1686 { 1687 if (h->plt.refcount > 0) 1688 h->plt.refcount -= 1; 1689 } 1690 break; 1691 1692 default: 1693 break; 1694 } 1695 } 1696 1697 return TRUE; 1698 } 1699 1700 /* Adjust a symbol defined by a dynamic object and referenced by a 1701 regular object. The current definition is in some section of the 1702 dynamic object, but we're not including those sections. We have to 1703 change the definition to something the rest of the link can 1704 understand. */ 1705 1706 static bfd_boolean 1707 elf_i386_adjust_dynamic_symbol (struct bfd_link_info *info, 1708 struct elf_link_hash_entry *h) 1709 { 1710 struct elf_i386_link_hash_table *htab; 1711 asection *s; 1712 1713 /* If this is a function, put it in the procedure linkage table. We 1714 will fill in the contents of the procedure linkage table later, 1715 when we know the address of the .got section. */ 1716 if (h->type == STT_FUNC 1717 || h->needs_plt) 1718 { 1719 if (h->plt.refcount <= 0 1720 || SYMBOL_CALLS_LOCAL (info, h) 1721 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT 1722 && h->root.type == bfd_link_hash_undefweak)) 1723 { 1724 /* This case can occur if we saw a PLT32 reloc in an input 1725 file, but the symbol was never referred to by a dynamic 1726 object, or if all references were garbage collected. In 1727 such a case, we don't actually need to build a procedure 1728 linkage table, and we can just do a PC32 reloc instead. */ 1729 h->plt.offset = (bfd_vma) -1; 1730 h->needs_plt = 0; 1731 } 1732 1733 return TRUE; 1734 } 1735 else 1736 /* It's possible that we incorrectly decided a .plt reloc was 1737 needed for an R_386_PC32 reloc to a non-function sym in 1738 check_relocs. We can't decide accurately between function and 1739 non-function syms in check-relocs; Objects loaded later in 1740 the link may change h->type. So fix it now. */ 1741 h->plt.offset = (bfd_vma) -1; 1742 1743 /* If this is a weak symbol, and there is a real definition, the 1744 processor independent code will have arranged for us to see the 1745 real definition first, and we can just use the same value. */ 1746 if (h->u.weakdef != NULL) 1747 { 1748 BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined 1749 || h->u.weakdef->root.type == bfd_link_hash_defweak); 1750 h->root.u.def.section = h->u.weakdef->root.u.def.section; 1751 h->root.u.def.value = h->u.weakdef->root.u.def.value; 1752 if (ELIMINATE_COPY_RELOCS || info->nocopyreloc) 1753 h->non_got_ref = h->u.weakdef->non_got_ref; 1754 return TRUE; 1755 } 1756 1757 /* This is a reference to a symbol defined by a dynamic object which 1758 is not a function. */ 1759 1760 /* If we are creating a shared library, we must presume that the 1761 only references to the symbol are via the global offset table. 1762 For such cases we need not do anything here; the relocations will 1763 be handled correctly by relocate_section. */ 1764 if (info->shared) 1765 return TRUE; 1766 1767 /* If there are no references to this symbol that do not use the 1768 GOT, we don't need to generate a copy reloc. */ 1769 if (!h->non_got_ref) 1770 return TRUE; 1771 1772 /* If -z nocopyreloc was given, we won't generate them either. */ 1773 if (info->nocopyreloc) 1774 { 1775 h->non_got_ref = 0; 1776 return TRUE; 1777 } 1778 1779 htab = elf_i386_hash_table (info); 1780 1781 /* If there aren't any dynamic relocs in read-only sections, then 1782 we can keep the dynamic relocs and avoid the copy reloc. This 1783 doesn't work on VxWorks, where we can not have dynamic relocations 1784 (other than copy and jump slot relocations) in an executable. */ 1785 if (ELIMINATE_COPY_RELOCS && !htab->is_vxworks) 1786 { 1787 struct elf_i386_link_hash_entry * eh; 1788 struct elf_i386_dyn_relocs *p; 1789 1790 eh = (struct elf_i386_link_hash_entry *) h; 1791 for (p = eh->dyn_relocs; p != NULL; p = p->next) 1792 { 1793 s = p->sec->output_section; 1794 if (s != NULL && (s->flags & SEC_READONLY) != 0) 1795 break; 1796 } 1797 1798 if (p == NULL) 1799 { 1800 h->non_got_ref = 0; 1801 return TRUE; 1802 } 1803 } 1804 1805 if (h->size == 0) 1806 { 1807 (*_bfd_error_handler) (_("dynamic variable `%s' is zero size"), 1808 h->root.root.string); 1809 return TRUE; 1810 } 1811 1812 /* We must allocate the symbol in our .dynbss section, which will 1813 become part of the .bss section of the executable. There will be 1814 an entry for this symbol in the .dynsym section. The dynamic 1815 object will contain position independent code, so all references 1816 from the dynamic object to this symbol will go through the global 1817 offset table. The dynamic linker will use the .dynsym entry to 1818 determine the address it must put in the global offset table, so 1819 both the dynamic object and the regular object will refer to the 1820 same memory location for the variable. */ 1821 1822 /* We must generate a R_386_COPY reloc to tell the dynamic linker to 1823 copy the initial value out of the dynamic object and into the 1824 runtime process image. */ 1825 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0) 1826 { 1827 htab->srelbss->size += sizeof (Elf32_External_Rel); 1828 h->needs_copy = 1; 1829 } 1830 1831 s = htab->sdynbss; 1832 1833 return _bfd_elf_adjust_dynamic_copy (h, s); 1834 } 1835 1836 /* Allocate space in .plt, .got and associated reloc sections for 1837 dynamic relocs. */ 1838 1839 static bfd_boolean 1840 allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf) 1841 { 1842 struct bfd_link_info *info; 1843 struct elf_i386_link_hash_table *htab; 1844 struct elf_i386_link_hash_entry *eh; 1845 struct elf_i386_dyn_relocs *p; 1846 1847 if (h->root.type == bfd_link_hash_indirect) 1848 return TRUE; 1849 1850 if (h->root.type == bfd_link_hash_warning) 1851 /* When warning symbols are created, they **replace** the "real" 1852 entry in the hash table, thus we never get to see the real 1853 symbol in a hash traversal. So look at it now. */ 1854 h = (struct elf_link_hash_entry *) h->root.u.i.link; 1855 1856 info = (struct bfd_link_info *) inf; 1857 htab = elf_i386_hash_table (info); 1858 1859 if (htab->elf.dynamic_sections_created 1860 && h->plt.refcount > 0) 1861 { 1862 /* Make sure this symbol is output as a dynamic symbol. 1863 Undefined weak syms won't yet be marked as dynamic. */ 1864 if (h->dynindx == -1 1865 && !h->forced_local) 1866 { 1867 if (! bfd_elf_link_record_dynamic_symbol (info, h)) 1868 return FALSE; 1869 } 1870 1871 if (info->shared 1872 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h)) 1873 { 1874 asection *s = htab->splt; 1875 1876 /* If this is the first .plt entry, make room for the special 1877 first entry. */ 1878 if (s->size == 0) 1879 s->size += PLT_ENTRY_SIZE; 1880 1881 h->plt.offset = s->size; 1882 1883 /* If this symbol is not defined in a regular file, and we are 1884 not generating a shared library, then set the symbol to this 1885 location in the .plt. This is required to make function 1886 pointers compare as equal between the normal executable and 1887 the shared library. */ 1888 if (! info->shared 1889 && !h->def_regular) 1890 { 1891 h->root.u.def.section = s; 1892 h->root.u.def.value = h->plt.offset; 1893 } 1894 1895 /* Make room for this entry. */ 1896 s->size += PLT_ENTRY_SIZE; 1897 1898 /* We also need to make an entry in the .got.plt section, which 1899 will be placed in the .got section by the linker script. */ 1900 htab->sgotplt->size += 4; 1901 1902 /* We also need to make an entry in the .rel.plt section. */ 1903 htab->srelplt->size += sizeof (Elf32_External_Rel); 1904 htab->next_tls_desc_index++; 1905 1906 if (htab->is_vxworks && !info->shared) 1907 { 1908 /* VxWorks has a second set of relocations for each PLT entry 1909 in executables. They go in a separate relocation section, 1910 which is processed by the kernel loader. */ 1911 1912 /* There are two relocations for the initial PLT entry: an 1913 R_386_32 relocation for _GLOBAL_OFFSET_TABLE_ + 4 and an 1914 R_386_32 relocation for _GLOBAL_OFFSET_TABLE_ + 8. */ 1915 1916 if (h->plt.offset == PLT_ENTRY_SIZE) 1917 htab->srelplt2->size += (sizeof (Elf32_External_Rel) * 2); 1918 1919 /* There are two extra relocations for each subsequent PLT entry: 1920 an R_386_32 relocation for the GOT entry, and an R_386_32 1921 relocation for the PLT entry. */ 1922 1923 htab->srelplt2->size += (sizeof (Elf32_External_Rel) * 2); 1924 } 1925 } 1926 else 1927 { 1928 h->plt.offset = (bfd_vma) -1; 1929 h->needs_plt = 0; 1930 } 1931 } 1932 else 1933 { 1934 h->plt.offset = (bfd_vma) -1; 1935 h->needs_plt = 0; 1936 } 1937 1938 eh = (struct elf_i386_link_hash_entry *) h; 1939 eh->tlsdesc_got = (bfd_vma) -1; 1940 1941 /* If R_386_TLS_{IE_32,IE,GOTIE} symbol is now local to the binary, 1942 make it a R_386_TLS_LE_32 requiring no TLS entry. */ 1943 if (h->got.refcount > 0 1944 && !info->shared 1945 && h->dynindx == -1 1946 && (elf_i386_hash_entry(h)->tls_type & GOT_TLS_IE)) 1947 h->got.offset = (bfd_vma) -1; 1948 else if (h->got.refcount > 0) 1949 { 1950 asection *s; 1951 bfd_boolean dyn; 1952 int tls_type = elf_i386_hash_entry(h)->tls_type; 1953 1954 /* Make sure this symbol is output as a dynamic symbol. 1955 Undefined weak syms won't yet be marked as dynamic. */ 1956 if (h->dynindx == -1 1957 && !h->forced_local) 1958 { 1959 if (! bfd_elf_link_record_dynamic_symbol (info, h)) 1960 return FALSE; 1961 } 1962 1963 s = htab->sgot; 1964 if (GOT_TLS_GDESC_P (tls_type)) 1965 { 1966 eh->tlsdesc_got = htab->sgotplt->size 1967 - elf_i386_compute_jump_table_size (htab); 1968 htab->sgotplt->size += 8; 1969 h->got.offset = (bfd_vma) -2; 1970 } 1971 if (! GOT_TLS_GDESC_P (tls_type) 1972 || GOT_TLS_GD_P (tls_type)) 1973 { 1974 h->got.offset = s->size; 1975 s->size += 4; 1976 /* R_386_TLS_GD needs 2 consecutive GOT slots. */ 1977 if (GOT_TLS_GD_P (tls_type) || tls_type == GOT_TLS_IE_BOTH) 1978 s->size += 4; 1979 } 1980 dyn = htab->elf.dynamic_sections_created; 1981 /* R_386_TLS_IE_32 needs one dynamic relocation, 1982 R_386_TLS_IE resp. R_386_TLS_GOTIE needs one dynamic relocation, 1983 (but if both R_386_TLS_IE_32 and R_386_TLS_IE is present, we 1984 need two), R_386_TLS_GD needs one if local symbol and two if 1985 global. */ 1986 if (tls_type == GOT_TLS_IE_BOTH) 1987 htab->srelgot->size += 2 * sizeof (Elf32_External_Rel); 1988 else if ((GOT_TLS_GD_P (tls_type) && h->dynindx == -1) 1989 || (tls_type & GOT_TLS_IE)) 1990 htab->srelgot->size += sizeof (Elf32_External_Rel); 1991 else if (GOT_TLS_GD_P (tls_type)) 1992 htab->srelgot->size += 2 * sizeof (Elf32_External_Rel); 1993 else if (! GOT_TLS_GDESC_P (tls_type) 1994 && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT 1995 || h->root.type != bfd_link_hash_undefweak) 1996 && (info->shared 1997 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h))) 1998 htab->srelgot->size += sizeof (Elf32_External_Rel); 1999 if (GOT_TLS_GDESC_P (tls_type)) 2000 htab->srelplt->size += sizeof (Elf32_External_Rel); 2001 } 2002 else 2003 h->got.offset = (bfd_vma) -1; 2004 2005 if (eh->dyn_relocs == NULL) 2006 return TRUE; 2007 2008 /* In the shared -Bsymbolic case, discard space allocated for 2009 dynamic pc-relative relocs against symbols which turn out to be 2010 defined in regular objects. For the normal shared case, discard 2011 space for pc-relative relocs that have become local due to symbol 2012 visibility changes. */ 2013 2014 if (info->shared) 2015 { 2016 /* The only reloc that uses pc_count is R_386_PC32, which will 2017 appear on a call or on something like ".long foo - .". We 2018 want calls to protected symbols to resolve directly to the 2019 function rather than going via the plt. If people want 2020 function pointer comparisons to work as expected then they 2021 should avoid writing assembly like ".long foo - .". */ 2022 if (SYMBOL_CALLS_LOCAL (info, h)) 2023 { 2024 struct elf_i386_dyn_relocs **pp; 2025 2026 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; ) 2027 { 2028 p->count -= p->pc_count; 2029 p->pc_count = 0; 2030 if (p->count == 0) 2031 *pp = p->next; 2032 else 2033 pp = &p->next; 2034 } 2035 } 2036 2037 if (htab->is_vxworks) 2038 { 2039 struct elf_i386_dyn_relocs **pp; 2040 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; ) 2041 { 2042 if (strcmp (p->sec->output_section->name, ".tls_vars") == 0) 2043 *pp = p->next; 2044 else 2045 pp = &p->next; 2046 } 2047 } 2048 2049 /* Also discard relocs on undefined weak syms with non-default 2050 visibility. */ 2051 if (eh->dyn_relocs != NULL 2052 && h->root.type == bfd_link_hash_undefweak) 2053 { 2054 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT) 2055 eh->dyn_relocs = NULL; 2056 2057 /* Make sure undefined weak symbols are output as a dynamic 2058 symbol in PIEs. */ 2059 else if (h->dynindx == -1 2060 && !h->forced_local) 2061 { 2062 if (! bfd_elf_link_record_dynamic_symbol (info, h)) 2063 return FALSE; 2064 } 2065 } 2066 } 2067 else if (ELIMINATE_COPY_RELOCS) 2068 { 2069 /* For the non-shared case, discard space for relocs against 2070 symbols which turn out to need copy relocs or are not 2071 dynamic. */ 2072 2073 if (!h->non_got_ref 2074 && ((h->def_dynamic 2075 && !h->def_regular) 2076 || (htab->elf.dynamic_sections_created 2077 && (h->root.type == bfd_link_hash_undefweak 2078 || h->root.type == bfd_link_hash_undefined)))) 2079 { 2080 /* Make sure this symbol is output as a dynamic symbol. 2081 Undefined weak syms won't yet be marked as dynamic. */ 2082 if (h->dynindx == -1 2083 && !h->forced_local) 2084 { 2085 if (! bfd_elf_link_record_dynamic_symbol (info, h)) 2086 return FALSE; 2087 } 2088 2089 /* If that succeeded, we know we'll be keeping all the 2090 relocs. */ 2091 if (h->dynindx != -1) 2092 goto keep; 2093 } 2094 2095 eh->dyn_relocs = NULL; 2096 2097 keep: ; 2098 } 2099 2100 /* Finally, allocate space. */ 2101 for (p = eh->dyn_relocs; p != NULL; p = p->next) 2102 { 2103 asection *sreloc = elf_section_data (p->sec)->sreloc; 2104 sreloc->size += p->count * sizeof (Elf32_External_Rel); 2105 } 2106 2107 return TRUE; 2108 } 2109 2110 /* Find any dynamic relocs that apply to read-only sections. */ 2111 2112 static bfd_boolean 2113 readonly_dynrelocs (struct elf_link_hash_entry *h, void *inf) 2114 { 2115 struct elf_i386_link_hash_entry *eh; 2116 struct elf_i386_dyn_relocs *p; 2117 2118 if (h->root.type == bfd_link_hash_warning) 2119 h = (struct elf_link_hash_entry *) h->root.u.i.link; 2120 2121 eh = (struct elf_i386_link_hash_entry *) h; 2122 for (p = eh->dyn_relocs; p != NULL; p = p->next) 2123 { 2124 asection *s = p->sec->output_section; 2125 2126 if (s != NULL && (s->flags & SEC_READONLY) != 0) 2127 { 2128 struct bfd_link_info *info = (struct bfd_link_info *) inf; 2129 if (info->warn_shared_textrel) 2130 (*_bfd_error_handler) 2131 (_("warning: dynamic relocation in readonly section `%s'"), 2132 h->root.root.string); 2133 info->flags |= DF_TEXTREL; 2134 2135 /* Not an error, just cut short the traversal. */ 2136 return FALSE; 2137 } 2138 } 2139 return TRUE; 2140 } 2141 2142 /* Set the sizes of the dynamic sections. */ 2143 2144 static bfd_boolean 2145 elf_i386_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED, 2146 struct bfd_link_info *info) 2147 { 2148 struct elf_i386_link_hash_table *htab; 2149 bfd *dynobj; 2150 asection *s; 2151 bfd_boolean relocs; 2152 bfd *ibfd; 2153 2154 htab = elf_i386_hash_table (info); 2155 dynobj = htab->elf.dynobj; 2156 if (dynobj == NULL) 2157 abort (); 2158 2159 if (htab->elf.dynamic_sections_created) 2160 { 2161 /* Set the contents of the .interp section to the interpreter. */ 2162 if (info->executable) 2163 { 2164 s = bfd_get_section_by_name (dynobj, ".interp"); 2165 if (s == NULL) 2166 abort (); 2167 s->size = sizeof ELF_DYNAMIC_INTERPRETER; 2168 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER; 2169 } 2170 } 2171 2172 /* Set up .got offsets for local syms, and space for local dynamic 2173 relocs. */ 2174 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next) 2175 { 2176 bfd_signed_vma *local_got; 2177 bfd_signed_vma *end_local_got; 2178 char *local_tls_type; 2179 bfd_vma *local_tlsdesc_gotent; 2180 bfd_size_type locsymcount; 2181 Elf_Internal_Shdr *symtab_hdr; 2182 asection *srel; 2183 2184 if (! is_i386_elf (ibfd)) 2185 continue; 2186 2187 for (s = ibfd->sections; s != NULL; s = s->next) 2188 { 2189 struct elf_i386_dyn_relocs *p; 2190 2191 for (p = ((struct elf_i386_dyn_relocs *) 2192 elf_section_data (s)->local_dynrel); 2193 p != NULL; 2194 p = p->next) 2195 { 2196 if (!bfd_is_abs_section (p->sec) 2197 && bfd_is_abs_section (p->sec->output_section)) 2198 { 2199 /* Input section has been discarded, either because 2200 it is a copy of a linkonce section or due to 2201 linker script /DISCARD/, so we'll be discarding 2202 the relocs too. */ 2203 } 2204 else if (htab->is_vxworks 2205 && strcmp (p->sec->output_section->name, 2206 ".tls_vars") == 0) 2207 { 2208 /* Relocations in vxworks .tls_vars sections are 2209 handled specially by the loader. */ 2210 } 2211 else if (p->count != 0) 2212 { 2213 srel = elf_section_data (p->sec)->sreloc; 2214 srel->size += p->count * sizeof (Elf32_External_Rel); 2215 if ((p->sec->output_section->flags & SEC_READONLY) != 0) 2216 info->flags |= DF_TEXTREL; 2217 } 2218 } 2219 } 2220 2221 local_got = elf_local_got_refcounts (ibfd); 2222 if (!local_got) 2223 continue; 2224 2225 symtab_hdr = &elf_symtab_hdr (ibfd); 2226 locsymcount = symtab_hdr->sh_info; 2227 end_local_got = local_got + locsymcount; 2228 local_tls_type = elf_i386_local_got_tls_type (ibfd); 2229 local_tlsdesc_gotent = elf_i386_local_tlsdesc_gotent (ibfd); 2230 s = htab->sgot; 2231 srel = htab->srelgot; 2232 for (; local_got < end_local_got; 2233 ++local_got, ++local_tls_type, ++local_tlsdesc_gotent) 2234 { 2235 *local_tlsdesc_gotent = (bfd_vma) -1; 2236 if (*local_got > 0) 2237 { 2238 if (GOT_TLS_GDESC_P (*local_tls_type)) 2239 { 2240 *local_tlsdesc_gotent = htab->sgotplt->size 2241 - elf_i386_compute_jump_table_size (htab); 2242 htab->sgotplt->size += 8; 2243 *local_got = (bfd_vma) -2; 2244 } 2245 if (! GOT_TLS_GDESC_P (*local_tls_type) 2246 || GOT_TLS_GD_P (*local_tls_type)) 2247 { 2248 *local_got = s->size; 2249 s->size += 4; 2250 if (GOT_TLS_GD_P (*local_tls_type) 2251 || *local_tls_type == GOT_TLS_IE_BOTH) 2252 s->size += 4; 2253 } 2254 if (info->shared 2255 || GOT_TLS_GD_ANY_P (*local_tls_type) 2256 || (*local_tls_type & GOT_TLS_IE)) 2257 { 2258 if (*local_tls_type == GOT_TLS_IE_BOTH) 2259 srel->size += 2 * sizeof (Elf32_External_Rel); 2260 else if (GOT_TLS_GD_P (*local_tls_type) 2261 || ! GOT_TLS_GDESC_P (*local_tls_type)) 2262 srel->size += sizeof (Elf32_External_Rel); 2263 if (GOT_TLS_GDESC_P (*local_tls_type)) 2264 htab->srelplt->size += sizeof (Elf32_External_Rel); 2265 } 2266 } 2267 else 2268 *local_got = (bfd_vma) -1; 2269 } 2270 } 2271 2272 if (htab->tls_ldm_got.refcount > 0) 2273 { 2274 /* Allocate 2 got entries and 1 dynamic reloc for R_386_TLS_LDM 2275 relocs. */ 2276 htab->tls_ldm_got.offset = htab->sgot->size; 2277 htab->sgot->size += 8; 2278 htab->srelgot->size += sizeof (Elf32_External_Rel); 2279 } 2280 else 2281 htab->tls_ldm_got.offset = -1; 2282 2283 /* Allocate global sym .plt and .got entries, and space for global 2284 sym dynamic relocs. */ 2285 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info); 2286 2287 /* For every jump slot reserved in the sgotplt, reloc_count is 2288 incremented. However, when we reserve space for TLS descriptors, 2289 it's not incremented, so in order to compute the space reserved 2290 for them, it suffices to multiply the reloc count by the jump 2291 slot size. */ 2292 if (htab->srelplt) 2293 htab->sgotplt_jump_table_size = htab->next_tls_desc_index * 4; 2294 2295 /* We now have determined the sizes of the various dynamic sections. 2296 Allocate memory for them. */ 2297 relocs = FALSE; 2298 for (s = dynobj->sections; s != NULL; s = s->next) 2299 { 2300 bfd_boolean strip_section = TRUE; 2301 2302 if ((s->flags & SEC_LINKER_CREATED) == 0) 2303 continue; 2304 2305 if (s == htab->splt 2306 || s == htab->sgot 2307 || s == htab->sgotplt 2308 || s == htab->sdynbss) 2309 { 2310 /* Strip this section if we don't need it; see the 2311 comment below. */ 2312 /* We'd like to strip these sections if they aren't needed, but if 2313 we've exported dynamic symbols from them we must leave them. 2314 It's too late to tell BFD to get rid of the symbols. */ 2315 2316 if (htab->elf.hplt != NULL) 2317 strip_section = FALSE; 2318 } 2319 else if (CONST_STRNEQ (bfd_get_section_name (dynobj, s), ".rel")) 2320 { 2321 if (s->size != 0 && s != htab->srelplt && s != htab->srelplt2) 2322 relocs = TRUE; 2323 2324 /* We use the reloc_count field as a counter if we need 2325 to copy relocs into the output file. */ 2326 s->reloc_count = 0; 2327 } 2328 else 2329 { 2330 /* It's not one of our sections, so don't allocate space. */ 2331 continue; 2332 } 2333 2334 if (s->size == 0) 2335 { 2336 /* If we don't need this section, strip it from the 2337 output file. This is mostly to handle .rel.bss and 2338 .rel.plt. We must create both sections in 2339 create_dynamic_sections, because they must be created 2340 before the linker maps input sections to output 2341 sections. The linker does that before 2342 adjust_dynamic_symbol is called, and it is that 2343 function which decides whether anything needs to go 2344 into these sections. */ 2345 if (strip_section) 2346 s->flags |= SEC_EXCLUDE; 2347 continue; 2348 } 2349 2350 if ((s->flags & SEC_HAS_CONTENTS) == 0) 2351 continue; 2352 2353 /* Allocate memory for the section contents. We use bfd_zalloc 2354 here in case unused entries are not reclaimed before the 2355 section's contents are written out. This should not happen, 2356 but this way if it does, we get a R_386_NONE reloc instead 2357 of garbage. */ 2358 s->contents = bfd_zalloc (dynobj, s->size); 2359 if (s->contents == NULL) 2360 return FALSE; 2361 } 2362 2363 if (htab->elf.dynamic_sections_created) 2364 { 2365 /* Add some entries to the .dynamic section. We fill in the 2366 values later, in elf_i386_finish_dynamic_sections, but we 2367 must add the entries now so that we get the correct size for 2368 the .dynamic section. The DT_DEBUG entry is filled in by the 2369 dynamic linker and used by the debugger. */ 2370 #define add_dynamic_entry(TAG, VAL) \ 2371 _bfd_elf_add_dynamic_entry (info, TAG, VAL) 2372 2373 if (info->executable) 2374 { 2375 if (!add_dynamic_entry (DT_DEBUG, 0)) 2376 return FALSE; 2377 } 2378 2379 if (htab->splt->size != 0) 2380 { 2381 if (!add_dynamic_entry (DT_PLTGOT, 0) 2382 || !add_dynamic_entry (DT_PLTRELSZ, 0) 2383 || !add_dynamic_entry (DT_PLTREL, DT_REL) 2384 || !add_dynamic_entry (DT_JMPREL, 0)) 2385 return FALSE; 2386 } 2387 2388 if (relocs) 2389 { 2390 if (!add_dynamic_entry (DT_REL, 0) 2391 || !add_dynamic_entry (DT_RELSZ, 0) 2392 || !add_dynamic_entry (DT_RELENT, sizeof (Elf32_External_Rel))) 2393 return FALSE; 2394 2395 /* If any dynamic relocs apply to a read-only section, 2396 then we need a DT_TEXTREL entry. */ 2397 if ((info->flags & DF_TEXTREL) == 0) 2398 elf_link_hash_traverse (&htab->elf, readonly_dynrelocs, 2399 (PTR) info); 2400 2401 if ((info->flags & DF_TEXTREL) != 0) 2402 { 2403 if (!add_dynamic_entry (DT_TEXTREL, 0)) 2404 return FALSE; 2405 } 2406 } 2407 if (htab->is_vxworks 2408 && !elf_vxworks_add_dynamic_entries (output_bfd, info)) 2409 return FALSE; 2410 } 2411 #undef add_dynamic_entry 2412 2413 return TRUE; 2414 } 2415 2416 static bfd_boolean 2417 elf_i386_always_size_sections (bfd *output_bfd, 2418 struct bfd_link_info *info) 2419 { 2420 asection *tls_sec = elf_hash_table (info)->tls_sec; 2421 2422 if (tls_sec) 2423 { 2424 struct elf_link_hash_entry *tlsbase; 2425 2426 tlsbase = elf_link_hash_lookup (elf_hash_table (info), 2427 "_TLS_MODULE_BASE_", 2428 FALSE, FALSE, FALSE); 2429 2430 if (tlsbase && tlsbase->type == STT_TLS) 2431 { 2432 struct bfd_link_hash_entry *bh = NULL; 2433 const struct elf_backend_data *bed 2434 = get_elf_backend_data (output_bfd); 2435 2436 if (!(_bfd_generic_link_add_one_symbol 2437 (info, output_bfd, "_TLS_MODULE_BASE_", BSF_LOCAL, 2438 tls_sec, 0, NULL, FALSE, 2439 bed->collect, &bh))) 2440 return FALSE; 2441 2442 elf_i386_hash_table (info)->tls_module_base = bh; 2443 2444 tlsbase = (struct elf_link_hash_entry *)bh; 2445 tlsbase->def_regular = 1; 2446 tlsbase->other = STV_HIDDEN; 2447 (*bed->elf_backend_hide_symbol) (info, tlsbase, TRUE); 2448 } 2449 } 2450 2451 return TRUE; 2452 } 2453 2454 /* Set the correct type for an x86 ELF section. We do this by the 2455 section name, which is a hack, but ought to work. */ 2456 2457 static bfd_boolean 2458 elf_i386_fake_sections (bfd *abfd ATTRIBUTE_UNUSED, 2459 Elf_Internal_Shdr *hdr, 2460 asection *sec) 2461 { 2462 register const char *name; 2463 2464 name = bfd_get_section_name (abfd, sec); 2465 2466 /* This is an ugly, but unfortunately necessary hack that is 2467 needed when producing EFI binaries on x86. It tells 2468 elf.c:elf_fake_sections() not to consider ".reloc" as a section 2469 containing ELF relocation info. We need this hack in order to 2470 be able to generate ELF binaries that can be translated into 2471 EFI applications (which are essentially COFF objects). Those 2472 files contain a COFF ".reloc" section inside an ELFNN object, 2473 which would normally cause BFD to segfault because it would 2474 attempt to interpret this section as containing relocation 2475 entries for section "oc". With this hack enabled, ".reloc" 2476 will be treated as a normal data section, which will avoid the 2477 segfault. However, you won't be able to create an ELFNN binary 2478 with a section named "oc" that needs relocations, but that's 2479 the kind of ugly side-effects you get when detecting section 2480 types based on their names... In practice, this limitation is 2481 unlikely to bite. */ 2482 if (strcmp (name, ".reloc") == 0) 2483 hdr->sh_type = SHT_PROGBITS; 2484 2485 return TRUE; 2486 } 2487 2488 /* _TLS_MODULE_BASE_ needs to be treated especially when linking 2489 executables. Rather than setting it to the beginning of the TLS 2490 section, we have to set it to the end. This function may be called 2491 multiple times, it is idempotent. */ 2492 2493 static void 2494 set_tls_module_base (struct bfd_link_info *info) 2495 { 2496 struct bfd_link_hash_entry *base; 2497 2498 if (!info->executable) 2499 return; 2500 2501 base = elf_i386_hash_table (info)->tls_module_base; 2502 2503 if (!base) 2504 return; 2505 2506 base->u.def.value = elf_hash_table (info)->tls_size; 2507 } 2508 2509 /* Return the base VMA address which should be subtracted from real addresses 2510 when resolving @dtpoff relocation. 2511 This is PT_TLS segment p_vaddr. */ 2512 2513 static bfd_vma 2514 dtpoff_base (struct bfd_link_info *info) 2515 { 2516 /* If tls_sec is NULL, we should have signalled an error already. */ 2517 if (elf_hash_table (info)->tls_sec == NULL) 2518 return 0; 2519 return elf_hash_table (info)->tls_sec->vma; 2520 } 2521 2522 /* Return the relocation value for @tpoff relocation 2523 if STT_TLS virtual address is ADDRESS. */ 2524 2525 static bfd_vma 2526 tpoff (struct bfd_link_info *info, bfd_vma address) 2527 { 2528 struct elf_link_hash_table *htab = elf_hash_table (info); 2529 2530 /* If tls_sec is NULL, we should have signalled an error already. */ 2531 if (htab->tls_sec == NULL) 2532 return 0; 2533 return htab->tls_size + htab->tls_sec->vma - address; 2534 } 2535 2536 /* Relocate an i386 ELF section. */ 2537 2538 static bfd_boolean 2539 elf_i386_relocate_section (bfd *output_bfd, 2540 struct bfd_link_info *info, 2541 bfd *input_bfd, 2542 asection *input_section, 2543 bfd_byte *contents, 2544 Elf_Internal_Rela *relocs, 2545 Elf_Internal_Sym *local_syms, 2546 asection **local_sections) 2547 { 2548 struct elf_i386_link_hash_table *htab; 2549 Elf_Internal_Shdr *symtab_hdr; 2550 struct elf_link_hash_entry **sym_hashes; 2551 bfd_vma *local_got_offsets; 2552 bfd_vma *local_tlsdesc_gotents; 2553 Elf_Internal_Rela *rel; 2554 Elf_Internal_Rela *relend; 2555 bfd_boolean is_vxworks_tls; 2556 2557 BFD_ASSERT (is_i386_elf (input_bfd)); 2558 2559 htab = elf_i386_hash_table (info); 2560 symtab_hdr = &elf_symtab_hdr (input_bfd); 2561 sym_hashes = elf_sym_hashes (input_bfd); 2562 local_got_offsets = elf_local_got_offsets (input_bfd); 2563 local_tlsdesc_gotents = elf_i386_local_tlsdesc_gotent (input_bfd); 2564 /* We have to handle relocations in vxworks .tls_vars sections 2565 specially, because the dynamic loader is 'weird'. */ 2566 is_vxworks_tls = (htab->is_vxworks && info->shared 2567 && !strcmp (input_section->output_section->name, 2568 ".tls_vars")); 2569 2570 set_tls_module_base (info); 2571 2572 rel = relocs; 2573 relend = relocs + input_section->reloc_count; 2574 for (; rel < relend; rel++) 2575 { 2576 unsigned int r_type; 2577 reloc_howto_type *howto; 2578 unsigned long r_symndx; 2579 struct elf_link_hash_entry *h; 2580 Elf_Internal_Sym *sym; 2581 asection *sec; 2582 bfd_vma off, offplt; 2583 bfd_vma relocation; 2584 bfd_boolean unresolved_reloc; 2585 bfd_reloc_status_type r; 2586 unsigned int indx; 2587 int tls_type; 2588 2589 r_type = ELF32_R_TYPE (rel->r_info); 2590 if (r_type == R_386_GNU_VTINHERIT 2591 || r_type == R_386_GNU_VTENTRY) 2592 continue; 2593 2594 if ((indx = r_type) >= R_386_standard 2595 && ((indx = r_type - R_386_ext_offset) - R_386_standard 2596 >= R_386_ext - R_386_standard) 2597 && ((indx = r_type - R_386_tls_offset) - R_386_ext 2598 >= R_386_tls - R_386_ext)) 2599 { 2600 (*_bfd_error_handler) 2601 (_("%B: unrecognized relocation (0x%x) in section `%A'"), 2602 input_bfd, input_section, r_type); 2603 bfd_set_error (bfd_error_bad_value); 2604 return FALSE; 2605 } 2606 howto = elf_howto_table + indx; 2607 2608 r_symndx = ELF32_R_SYM (rel->r_info); 2609 h = NULL; 2610 sym = NULL; 2611 sec = NULL; 2612 unresolved_reloc = FALSE; 2613 if (r_symndx < symtab_hdr->sh_info) 2614 { 2615 sym = local_syms + r_symndx; 2616 sec = local_sections[r_symndx]; 2617 relocation = (sec->output_section->vma 2618 + sec->output_offset 2619 + sym->st_value); 2620 2621 if (ELF_ST_TYPE (sym->st_info) == STT_SECTION 2622 && ((sec->flags & SEC_MERGE) != 0 2623 || (info->relocatable 2624 && sec->output_offset != 0))) 2625 { 2626 bfd_vma addend; 2627 bfd_byte *where = contents + rel->r_offset; 2628 2629 switch (howto->size) 2630 { 2631 case 0: 2632 addend = bfd_get_8 (input_bfd, where); 2633 if (howto->pc_relative) 2634 { 2635 addend = (addend ^ 0x80) - 0x80; 2636 addend += 1; 2637 } 2638 break; 2639 case 1: 2640 addend = bfd_get_16 (input_bfd, where); 2641 if (howto->pc_relative) 2642 { 2643 addend = (addend ^ 0x8000) - 0x8000; 2644 addend += 2; 2645 } 2646 break; 2647 case 2: 2648 addend = bfd_get_32 (input_bfd, where); 2649 if (howto->pc_relative) 2650 { 2651 addend = (addend ^ 0x80000000) - 0x80000000; 2652 addend += 4; 2653 } 2654 break; 2655 default: 2656 abort (); 2657 } 2658 2659 if (info->relocatable) 2660 addend += sec->output_offset; 2661 else 2662 { 2663 asection *msec = sec; 2664 addend = _bfd_elf_rel_local_sym (output_bfd, sym, &msec, 2665 addend); 2666 addend -= relocation; 2667 addend += msec->output_section->vma + msec->output_offset; 2668 } 2669 2670 switch (howto->size) 2671 { 2672 case 0: 2673 /* FIXME: overflow checks. */ 2674 if (howto->pc_relative) 2675 addend -= 1; 2676 bfd_put_8 (input_bfd, addend, where); 2677 break; 2678 case 1: 2679 if (howto->pc_relative) 2680 addend -= 2; 2681 bfd_put_16 (input_bfd, addend, where); 2682 break; 2683 case 2: 2684 if (howto->pc_relative) 2685 addend -= 4; 2686 bfd_put_32 (input_bfd, addend, where); 2687 break; 2688 } 2689 } 2690 } 2691 else 2692 { 2693 bfd_boolean warned; 2694 2695 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel, 2696 r_symndx, symtab_hdr, sym_hashes, 2697 h, sec, relocation, 2698 unresolved_reloc, warned); 2699 } 2700 2701 if (sec != NULL && elf_discarded_section (sec)) 2702 { 2703 /* For relocs against symbols from removed linkonce sections, 2704 or sections discarded by a linker script, we just want the 2705 section contents zeroed. Avoid any special processing. */ 2706 _bfd_clear_contents (howto, input_bfd, contents + rel->r_offset); 2707 rel->r_info = 0; 2708 rel->r_addend = 0; 2709 continue; 2710 } 2711 2712 if (info->relocatable) 2713 continue; 2714 2715 switch (r_type) 2716 { 2717 case R_386_GOT32: 2718 /* Relocation is to the entry for this symbol in the global 2719 offset table. */ 2720 if (htab->sgot == NULL) 2721 abort (); 2722 2723 if (h != NULL) 2724 { 2725 bfd_boolean dyn; 2726 2727 off = h->got.offset; 2728 dyn = htab->elf.dynamic_sections_created; 2729 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info->shared, h) 2730 || (info->shared 2731 && SYMBOL_REFERENCES_LOCAL (info, h)) 2732 || (ELF_ST_VISIBILITY (h->other) 2733 && h->root.type == bfd_link_hash_undefweak)) 2734 { 2735 /* This is actually a static link, or it is a 2736 -Bsymbolic link and the symbol is defined 2737 locally, or the symbol was forced to be local 2738 because of a version file. We must initialize 2739 this entry in the global offset table. Since the 2740 offset must always be a multiple of 4, we use the 2741 least significant bit to record whether we have 2742 initialized it already. 2743 2744 When doing a dynamic link, we create a .rel.got 2745 relocation entry to initialize the value. This 2746 is done in the finish_dynamic_symbol routine. */ 2747 if ((off & 1) != 0) 2748 off &= ~1; 2749 else 2750 { 2751 bfd_put_32 (output_bfd, relocation, 2752 htab->sgot->contents + off); 2753 h->got.offset |= 1; 2754 } 2755 } 2756 else 2757 unresolved_reloc = FALSE; 2758 } 2759 else 2760 { 2761 if (local_got_offsets == NULL) 2762 abort (); 2763 2764 off = local_got_offsets[r_symndx]; 2765 2766 /* The offset must always be a multiple of 4. We use 2767 the least significant bit to record whether we have 2768 already generated the necessary reloc. */ 2769 if ((off & 1) != 0) 2770 off &= ~1; 2771 else 2772 { 2773 bfd_put_32 (output_bfd, relocation, 2774 htab->sgot->contents + off); 2775 2776 if (info->shared) 2777 { 2778 asection *s; 2779 Elf_Internal_Rela outrel; 2780 bfd_byte *loc; 2781 2782 s = htab->srelgot; 2783 if (s == NULL) 2784 abort (); 2785 2786 outrel.r_offset = (htab->sgot->output_section->vma 2787 + htab->sgot->output_offset 2788 + off); 2789 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE); 2790 loc = s->contents; 2791 loc += s->reloc_count++ * sizeof (Elf32_External_Rel); 2792 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc); 2793 } 2794 2795 local_got_offsets[r_symndx] |= 1; 2796 } 2797 } 2798 2799 if (off >= (bfd_vma) -2) 2800 abort (); 2801 2802 relocation = htab->sgot->output_section->vma 2803 + htab->sgot->output_offset + off 2804 - htab->sgotplt->output_section->vma 2805 - htab->sgotplt->output_offset; 2806 break; 2807 2808 case R_386_GOTOFF: 2809 /* Relocation is relative to the start of the global offset 2810 table. */ 2811 2812 /* Check to make sure it isn't a protected function symbol 2813 for shared library since it may not be local when used 2814 as function address. We also need to make sure that a 2815 symbol is defined locally. */ 2816 if (info->shared && h) 2817 { 2818 if (!h->def_regular) 2819 { 2820 const char *v; 2821 2822 switch (ELF_ST_VISIBILITY (h->other)) 2823 { 2824 case STV_HIDDEN: 2825 v = _("hidden symbol"); 2826 break; 2827 case STV_INTERNAL: 2828 v = _("internal symbol"); 2829 break; 2830 case STV_PROTECTED: 2831 v = _("protected symbol"); 2832 break; 2833 default: 2834 v = _("symbol"); 2835 break; 2836 } 2837 2838 (*_bfd_error_handler) 2839 (_("%B: relocation R_386_GOTOFF against undefined %s `%s' can not be used when making a shared object"), 2840 input_bfd, v, h->root.root.string); 2841 bfd_set_error (bfd_error_bad_value); 2842 return FALSE; 2843 } 2844 else if (!info->executable 2845 && h->type == STT_FUNC 2846 && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED) 2847 { 2848 (*_bfd_error_handler) 2849 (_("%B: relocation R_386_GOTOFF against protected function `%s' can not be used when making a shared object"), 2850 input_bfd, h->root.root.string); 2851 bfd_set_error (bfd_error_bad_value); 2852 return FALSE; 2853 } 2854 } 2855 2856 /* Note that sgot is not involved in this 2857 calculation. We always want the start of .got.plt. If we 2858 defined _GLOBAL_OFFSET_TABLE_ in a different way, as is 2859 permitted by the ABI, we might have to change this 2860 calculation. */ 2861 relocation -= htab->sgotplt->output_section->vma 2862 + htab->sgotplt->output_offset; 2863 break; 2864 2865 case R_386_GOTPC: 2866 /* Use global offset table as symbol value. */ 2867 relocation = htab->sgotplt->output_section->vma 2868 + htab->sgotplt->output_offset; 2869 unresolved_reloc = FALSE; 2870 break; 2871 2872 case R_386_PLT32: 2873 /* Relocation is to the entry for this symbol in the 2874 procedure linkage table. */ 2875 2876 /* Resolve a PLT32 reloc against a local symbol directly, 2877 without using the procedure linkage table. */ 2878 if (h == NULL) 2879 break; 2880 2881 if (h->plt.offset == (bfd_vma) -1 2882 || htab->splt == NULL) 2883 { 2884 /* We didn't make a PLT entry for this symbol. This 2885 happens when statically linking PIC code, or when 2886 using -Bsymbolic. */ 2887 break; 2888 } 2889 2890 relocation = (htab->splt->output_section->vma 2891 + htab->splt->output_offset 2892 + h->plt.offset); 2893 unresolved_reloc = FALSE; 2894 break; 2895 2896 case R_386_32: 2897 case R_386_PC32: 2898 if ((input_section->flags & SEC_ALLOC) == 0 2899 || is_vxworks_tls) 2900 break; 2901 2902 if ((info->shared 2903 && (h == NULL 2904 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT 2905 || h->root.type != bfd_link_hash_undefweak) 2906 && (r_type != R_386_PC32 2907 || !SYMBOL_CALLS_LOCAL (info, h))) 2908 || (ELIMINATE_COPY_RELOCS 2909 && !info->shared 2910 && h != NULL 2911 && h->dynindx != -1 2912 && !h->non_got_ref 2913 && ((h->def_dynamic 2914 && !h->def_regular) 2915 || h->root.type == bfd_link_hash_undefweak 2916 || h->root.type == bfd_link_hash_undefined))) 2917 { 2918 Elf_Internal_Rela outrel; 2919 bfd_byte *loc; 2920 bfd_boolean skip, relocate; 2921 asection *sreloc; 2922 2923 /* When generating a shared object, these relocations 2924 are copied into the output file to be resolved at run 2925 time. */ 2926 2927 skip = FALSE; 2928 relocate = FALSE; 2929 2930 outrel.r_offset = 2931 _bfd_elf_section_offset (output_bfd, info, input_section, 2932 rel->r_offset); 2933 if (outrel.r_offset == (bfd_vma) -1) 2934 skip = TRUE; 2935 else if (outrel.r_offset == (bfd_vma) -2) 2936 skip = TRUE, relocate = TRUE; 2937 outrel.r_offset += (input_section->output_section->vma 2938 + input_section->output_offset); 2939 2940 if (skip) 2941 memset (&outrel, 0, sizeof outrel); 2942 else if (h != NULL 2943 && h->dynindx != -1 2944 && (r_type == R_386_PC32 2945 || !info->shared 2946 || !SYMBOLIC_BIND (info, h) 2947 || !h->def_regular)) 2948 outrel.r_info = ELF32_R_INFO (h->dynindx, r_type); 2949 else 2950 { 2951 /* This symbol is local, or marked to become local. */ 2952 relocate = TRUE; 2953 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE); 2954 } 2955 2956 sreloc = elf_section_data (input_section)->sreloc; 2957 if (sreloc == NULL) 2958 abort (); 2959 2960 loc = sreloc->contents; 2961 loc += sreloc->reloc_count++ * sizeof (Elf32_External_Rel); 2962 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc); 2963 2964 /* If this reloc is against an external symbol, we do 2965 not want to fiddle with the addend. Otherwise, we 2966 need to include the symbol value so that it becomes 2967 an addend for the dynamic reloc. */ 2968 if (! relocate) 2969 continue; 2970 } 2971 break; 2972 2973 case R_386_TLS_IE: 2974 if (info->shared) 2975 { 2976 Elf_Internal_Rela outrel; 2977 bfd_byte *loc; 2978 asection *sreloc; 2979 2980 outrel.r_offset = rel->r_offset 2981 + input_section->output_section->vma 2982 + input_section->output_offset; 2983 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE); 2984 sreloc = elf_section_data (input_section)->sreloc; 2985 if (sreloc == NULL) 2986 abort (); 2987 loc = sreloc->contents; 2988 loc += sreloc->reloc_count++ * sizeof (Elf32_External_Rel); 2989 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc); 2990 } 2991 /* Fall through */ 2992 2993 case R_386_TLS_GD: 2994 case R_386_TLS_GOTDESC: 2995 case R_386_TLS_DESC_CALL: 2996 case R_386_TLS_IE_32: 2997 case R_386_TLS_GOTIE: 2998 tls_type = GOT_UNKNOWN; 2999 if (h == NULL && local_got_offsets) 3000 tls_type = elf_i386_local_got_tls_type (input_bfd) [r_symndx]; 3001 else if (h != NULL) 3002 tls_type = elf_i386_hash_entry(h)->tls_type; 3003 if (tls_type == GOT_TLS_IE) 3004 tls_type = GOT_TLS_IE_NEG; 3005 3006 if (! elf_i386_tls_transition (info, input_bfd, 3007 input_section, contents, 3008 symtab_hdr, sym_hashes, 3009 &r_type, tls_type, rel, 3010 relend, h)) 3011 return FALSE; 3012 3013 if (r_type == R_386_TLS_LE_32) 3014 { 3015 BFD_ASSERT (! unresolved_reloc); 3016 if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_GD) 3017 { 3018 unsigned int type; 3019 bfd_vma roff; 3020 3021 /* GD->LE transition. */ 3022 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2); 3023 if (type == 0x04) 3024 { 3025 /* leal foo(,%reg,1), %eax; call ___tls_get_addr 3026 Change it into: 3027 movl %gs:0, %eax; subl $foo@tpoff, %eax 3028 (6 byte form of subl). */ 3029 memcpy (contents + rel->r_offset - 3, 3030 "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12); 3031 roff = rel->r_offset + 5; 3032 } 3033 else 3034 { 3035 /* leal foo(%reg), %eax; call ___tls_get_addr; nop 3036 Change it into: 3037 movl %gs:0, %eax; subl $foo@tpoff, %eax 3038 (6 byte form of subl). */ 3039 memcpy (contents + rel->r_offset - 2, 3040 "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12); 3041 roff = rel->r_offset + 6; 3042 } 3043 bfd_put_32 (output_bfd, tpoff (info, relocation), 3044 contents + roff); 3045 /* Skip R_386_PC32/R_386_PLT32. */ 3046 rel++; 3047 continue; 3048 } 3049 else if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_GOTDESC) 3050 { 3051 /* GDesc -> LE transition. 3052 It's originally something like: 3053 leal x@tlsdesc(%ebx), %eax 3054 3055 leal x@ntpoff, %eax 3056 3057 Registers other than %eax may be set up here. */ 3058 3059 unsigned int val; 3060 bfd_vma roff; 3061 3062 roff = rel->r_offset; 3063 val = bfd_get_8 (input_bfd, contents + roff - 1); 3064 3065 /* Now modify the instruction as appropriate. */ 3066 /* aoliva FIXME: remove the above and xor the byte 3067 below with 0x86. */ 3068 bfd_put_8 (output_bfd, val ^ 0x86, 3069 contents + roff - 1); 3070 bfd_put_32 (output_bfd, -tpoff (info, relocation), 3071 contents + roff); 3072 continue; 3073 } 3074 else if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_DESC_CALL) 3075 { 3076 /* GDesc -> LE transition. 3077 It's originally: 3078 call *(%eax) 3079 Turn it into: 3080 xchg %ax,%ax */ 3081 3082 bfd_vma roff; 3083 3084 roff = rel->r_offset; 3085 bfd_put_8 (output_bfd, 0x66, contents + roff); 3086 bfd_put_8 (output_bfd, 0x90, contents + roff + 1); 3087 continue; 3088 } 3089 else if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_IE) 3090 { 3091 unsigned int val; 3092 3093 /* IE->LE transition: 3094 Originally it can be one of: 3095 movl foo, %eax 3096 movl foo, %reg 3097 addl foo, %reg 3098 We change it into: 3099 movl $foo, %eax 3100 movl $foo, %reg 3101 addl $foo, %reg. */ 3102 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 1); 3103 if (val == 0xa1) 3104 { 3105 /* movl foo, %eax. */ 3106 bfd_put_8 (output_bfd, 0xb8, 3107 contents + rel->r_offset - 1); 3108 } 3109 else 3110 { 3111 unsigned int type; 3112 3113 type = bfd_get_8 (input_bfd, 3114 contents + rel->r_offset - 2); 3115 switch (type) 3116 { 3117 case 0x8b: 3118 /* movl */ 3119 bfd_put_8 (output_bfd, 0xc7, 3120 contents + rel->r_offset - 2); 3121 bfd_put_8 (output_bfd, 3122 0xc0 | ((val >> 3) & 7), 3123 contents + rel->r_offset - 1); 3124 break; 3125 case 0x03: 3126 /* addl */ 3127 bfd_put_8 (output_bfd, 0x81, 3128 contents + rel->r_offset - 2); 3129 bfd_put_8 (output_bfd, 3130 0xc0 | ((val >> 3) & 7), 3131 contents + rel->r_offset - 1); 3132 break; 3133 default: 3134 BFD_FAIL (); 3135 break; 3136 } 3137 } 3138 bfd_put_32 (output_bfd, -tpoff (info, relocation), 3139 contents + rel->r_offset); 3140 continue; 3141 } 3142 else 3143 { 3144 unsigned int val, type; 3145 3146 /* {IE_32,GOTIE}->LE transition: 3147 Originally it can be one of: 3148 subl foo(%reg1), %reg2 3149 movl foo(%reg1), %reg2 3150 addl foo(%reg1), %reg2 3151 We change it into: 3152 subl $foo, %reg2 3153 movl $foo, %reg2 (6 byte form) 3154 addl $foo, %reg2. */ 3155 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2); 3156 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 1); 3157 if (type == 0x8b) 3158 { 3159 /* movl */ 3160 bfd_put_8 (output_bfd, 0xc7, 3161 contents + rel->r_offset - 2); 3162 bfd_put_8 (output_bfd, 0xc0 | ((val >> 3) & 7), 3163 contents + rel->r_offset - 1); 3164 } 3165 else if (type == 0x2b) 3166 { 3167 /* subl */ 3168 bfd_put_8 (output_bfd, 0x81, 3169 contents + rel->r_offset - 2); 3170 bfd_put_8 (output_bfd, 0xe8 | ((val >> 3) & 7), 3171 contents + rel->r_offset - 1); 3172 } 3173 else if (type == 0x03) 3174 { 3175 /* addl */ 3176 bfd_put_8 (output_bfd, 0x81, 3177 contents + rel->r_offset - 2); 3178 bfd_put_8 (output_bfd, 0xc0 | ((val >> 3) & 7), 3179 contents + rel->r_offset - 1); 3180 } 3181 else 3182 BFD_FAIL (); 3183 if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_GOTIE) 3184 bfd_put_32 (output_bfd, -tpoff (info, relocation), 3185 contents + rel->r_offset); 3186 else 3187 bfd_put_32 (output_bfd, tpoff (info, relocation), 3188 contents + rel->r_offset); 3189 continue; 3190 } 3191 } 3192 3193 if (htab->sgot == NULL) 3194 abort (); 3195 3196 if (h != NULL) 3197 { 3198 off = h->got.offset; 3199 offplt = elf_i386_hash_entry (h)->tlsdesc_got; 3200 } 3201 else 3202 { 3203 if (local_got_offsets == NULL) 3204 abort (); 3205 3206 off = local_got_offsets[r_symndx]; 3207 offplt = local_tlsdesc_gotents[r_symndx]; 3208 } 3209 3210 if ((off & 1) != 0) 3211 off &= ~1; 3212 else 3213 { 3214 Elf_Internal_Rela outrel; 3215 bfd_byte *loc; 3216 int dr_type, indx; 3217 asection *sreloc; 3218 3219 if (htab->srelgot == NULL) 3220 abort (); 3221 3222 indx = h && h->dynindx != -1 ? h->dynindx : 0; 3223 3224 if (GOT_TLS_GDESC_P (tls_type)) 3225 { 3226 outrel.r_info = ELF32_R_INFO (indx, R_386_TLS_DESC); 3227 BFD_ASSERT (htab->sgotplt_jump_table_size + offplt + 8 3228 <= htab->sgotplt->size); 3229 outrel.r_offset = (htab->sgotplt->output_section->vma 3230 + htab->sgotplt->output_offset 3231 + offplt 3232 + htab->sgotplt_jump_table_size); 3233 sreloc = htab->srelplt; 3234 loc = sreloc->contents; 3235 loc += (htab->next_tls_desc_index++ 3236 * sizeof (Elf32_External_Rel)); 3237 BFD_ASSERT (loc + sizeof (Elf32_External_Rel) 3238 <= sreloc->contents + sreloc->size); 3239 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc); 3240 if (indx == 0) 3241 { 3242 BFD_ASSERT (! unresolved_reloc); 3243 bfd_put_32 (output_bfd, 3244 relocation - dtpoff_base (info), 3245 htab->sgotplt->contents + offplt 3246 + htab->sgotplt_jump_table_size + 4); 3247 } 3248 else 3249 { 3250 bfd_put_32 (output_bfd, 0, 3251 htab->sgotplt->contents + offplt 3252 + htab->sgotplt_jump_table_size + 4); 3253 } 3254 } 3255 3256 sreloc = htab->srelgot; 3257 3258 outrel.r_offset = (htab->sgot->output_section->vma 3259 + htab->sgot->output_offset + off); 3260 3261 if (GOT_TLS_GD_P (tls_type)) 3262 dr_type = R_386_TLS_DTPMOD32; 3263 else if (GOT_TLS_GDESC_P (tls_type)) 3264 goto dr_done; 3265 else if (tls_type == GOT_TLS_IE_POS) 3266 dr_type = R_386_TLS_TPOFF; 3267 else 3268 dr_type = R_386_TLS_TPOFF32; 3269 3270 if (dr_type == R_386_TLS_TPOFF && indx == 0) 3271 bfd_put_32 (output_bfd, relocation - dtpoff_base (info), 3272 htab->sgot->contents + off); 3273 else if (dr_type == R_386_TLS_TPOFF32 && indx == 0) 3274 bfd_put_32 (output_bfd, dtpoff_base (info) - relocation, 3275 htab->sgot->contents + off); 3276 else if (dr_type != R_386_TLS_DESC) 3277 bfd_put_32 (output_bfd, 0, 3278 htab->sgot->contents + off); 3279 outrel.r_info = ELF32_R_INFO (indx, dr_type); 3280 3281 loc = sreloc->contents; 3282 loc += sreloc->reloc_count++ * sizeof (Elf32_External_Rel); 3283 BFD_ASSERT (loc + sizeof (Elf32_External_Rel) 3284 <= sreloc->contents + sreloc->size); 3285 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc); 3286 3287 if (GOT_TLS_GD_P (tls_type)) 3288 { 3289 if (indx == 0) 3290 { 3291 BFD_ASSERT (! unresolved_reloc); 3292 bfd_put_32 (output_bfd, 3293 relocation - dtpoff_base (info), 3294 htab->sgot->contents + off + 4); 3295 } 3296 else 3297 { 3298 bfd_put_32 (output_bfd, 0, 3299 htab->sgot->contents + off + 4); 3300 outrel.r_info = ELF32_R_INFO (indx, 3301 R_386_TLS_DTPOFF32); 3302 outrel.r_offset += 4; 3303 sreloc->reloc_count++; 3304 loc += sizeof (Elf32_External_Rel); 3305 BFD_ASSERT (loc + sizeof (Elf32_External_Rel) 3306 <= sreloc->contents + sreloc->size); 3307 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc); 3308 } 3309 } 3310 else if (tls_type == GOT_TLS_IE_BOTH) 3311 { 3312 bfd_put_32 (output_bfd, 3313 indx == 0 ? relocation - dtpoff_base (info) : 0, 3314 htab->sgot->contents + off + 4); 3315 outrel.r_info = ELF32_R_INFO (indx, R_386_TLS_TPOFF); 3316 outrel.r_offset += 4; 3317 sreloc->reloc_count++; 3318 loc += sizeof (Elf32_External_Rel); 3319 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc); 3320 } 3321 3322 dr_done: 3323 if (h != NULL) 3324 h->got.offset |= 1; 3325 else 3326 local_got_offsets[r_symndx] |= 1; 3327 } 3328 3329 if (off >= (bfd_vma) -2 3330 && ! GOT_TLS_GDESC_P (tls_type)) 3331 abort (); 3332 if (r_type == R_386_TLS_GOTDESC 3333 || r_type == R_386_TLS_DESC_CALL) 3334 { 3335 relocation = htab->sgotplt_jump_table_size + offplt; 3336 unresolved_reloc = FALSE; 3337 } 3338 else if (r_type == ELF32_R_TYPE (rel->r_info)) 3339 { 3340 bfd_vma g_o_t = htab->sgotplt->output_section->vma 3341 + htab->sgotplt->output_offset; 3342 relocation = htab->sgot->output_section->vma 3343 + htab->sgot->output_offset + off - g_o_t; 3344 if ((r_type == R_386_TLS_IE || r_type == R_386_TLS_GOTIE) 3345 && tls_type == GOT_TLS_IE_BOTH) 3346 relocation += 4; 3347 if (r_type == R_386_TLS_IE) 3348 relocation += g_o_t; 3349 unresolved_reloc = FALSE; 3350 } 3351 else if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_GD) 3352 { 3353 unsigned int val, type; 3354 bfd_vma roff; 3355 3356 /* GD->IE transition. */ 3357 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2); 3358 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 1); 3359 if (type == 0x04) 3360 { 3361 /* leal foo(,%reg,1), %eax; call ___tls_get_addr 3362 Change it into: 3363 movl %gs:0, %eax; subl $foo@gottpoff(%reg), %eax. */ 3364 val >>= 3; 3365 roff = rel->r_offset - 3; 3366 } 3367 else 3368 { 3369 /* leal foo(%reg), %eax; call ___tls_get_addr; nop 3370 Change it into: 3371 movl %gs:0, %eax; subl $foo@gottpoff(%reg), %eax. */ 3372 roff = rel->r_offset - 2; 3373 } 3374 memcpy (contents + roff, 3375 "\x65\xa1\0\0\0\0\x2b\x80\0\0\0", 12); 3376 contents[roff + 7] = 0x80 | (val & 7); 3377 /* If foo is used only with foo@gotntpoff(%reg) and 3378 foo@indntpoff, but not with foo@gottpoff(%reg), change 3379 subl $foo@gottpoff(%reg), %eax 3380 into: 3381 addl $foo@gotntpoff(%reg), %eax. */ 3382 if (tls_type == GOT_TLS_IE_POS) 3383 contents[roff + 6] = 0x03; 3384 bfd_put_32 (output_bfd, 3385 htab->sgot->output_section->vma 3386 + htab->sgot->output_offset + off 3387 - htab->sgotplt->output_section->vma 3388 - htab->sgotplt->output_offset, 3389 contents + roff + 8); 3390 /* Skip R_386_PLT32. */ 3391 rel++; 3392 continue; 3393 } 3394 else if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_GOTDESC) 3395 { 3396 /* GDesc -> IE transition. 3397 It's originally something like: 3398 leal x@tlsdesc(%ebx), %eax 3399 3400 Change it to: 3401 movl x@gotntpoff(%ebx), %eax # before xchg %ax,%ax 3402 or: 3403 movl x@gottpoff(%ebx), %eax # before negl %eax 3404 3405 Registers other than %eax may be set up here. */ 3406 3407 bfd_vma roff; 3408 3409 /* First, make sure it's a leal adding ebx to a 32-bit 3410 offset into any register, although it's probably 3411 almost always going to be eax. */ 3412 roff = rel->r_offset; 3413 3414 /* Now modify the instruction as appropriate. */ 3415 /* To turn a leal into a movl in the form we use it, it 3416 suffices to change the first byte from 0x8d to 0x8b. 3417 aoliva FIXME: should we decide to keep the leal, all 3418 we have to do is remove the statement below, and 3419 adjust the relaxation of R_386_TLS_DESC_CALL. */ 3420 bfd_put_8 (output_bfd, 0x8b, contents + roff - 2); 3421 3422 if (tls_type == GOT_TLS_IE_BOTH) 3423 off += 4; 3424 3425 bfd_put_32 (output_bfd, 3426 htab->sgot->output_section->vma 3427 + htab->sgot->output_offset + off 3428 - htab->sgotplt->output_section->vma 3429 - htab->sgotplt->output_offset, 3430 contents + roff); 3431 continue; 3432 } 3433 else if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_DESC_CALL) 3434 { 3435 /* GDesc -> IE transition. 3436 It's originally: 3437 call *(%eax) 3438 3439 Change it to: 3440 xchg %ax,%ax 3441 or 3442 negl %eax 3443 depending on how we transformed the TLS_GOTDESC above. 3444 */ 3445 3446 bfd_vma roff; 3447 3448 roff = rel->r_offset; 3449 3450 /* Now modify the instruction as appropriate. */ 3451 if (tls_type != GOT_TLS_IE_NEG) 3452 { 3453 /* xchg %ax,%ax */ 3454 bfd_put_8 (output_bfd, 0x66, contents + roff); 3455 bfd_put_8 (output_bfd, 0x90, contents + roff + 1); 3456 } 3457 else 3458 { 3459 /* negl %eax */ 3460 bfd_put_8 (output_bfd, 0xf7, contents + roff); 3461 bfd_put_8 (output_bfd, 0xd8, contents + roff + 1); 3462 } 3463 3464 continue; 3465 } 3466 else 3467 BFD_ASSERT (FALSE); 3468 break; 3469 3470 case R_386_TLS_LDM: 3471 if (! elf_i386_tls_transition (info, input_bfd, 3472 input_section, contents, 3473 symtab_hdr, sym_hashes, 3474 &r_type, GOT_UNKNOWN, rel, 3475 relend, h)) 3476 return FALSE; 3477 3478 if (r_type != R_386_TLS_LDM) 3479 { 3480 /* LD->LE transition: 3481 leal foo(%reg), %eax; call ___tls_get_addr. 3482 We change it into: 3483 movl %gs:0, %eax; nop; leal 0(%esi,1), %esi. */ 3484 BFD_ASSERT (r_type == R_386_TLS_LE_32); 3485 memcpy (contents + rel->r_offset - 2, 3486 "\x65\xa1\0\0\0\0\x90\x8d\x74\x26", 11); 3487 /* Skip R_386_PC32/R_386_PLT32. */ 3488 rel++; 3489 continue; 3490 } 3491 3492 if (htab->sgot == NULL) 3493 abort (); 3494 3495 off = htab->tls_ldm_got.offset; 3496 if (off & 1) 3497 off &= ~1; 3498 else 3499 { 3500 Elf_Internal_Rela outrel; 3501 bfd_byte *loc; 3502 3503 if (htab->srelgot == NULL) 3504 abort (); 3505 3506 outrel.r_offset = (htab->sgot->output_section->vma 3507 + htab->sgot->output_offset + off); 3508 3509 bfd_put_32 (output_bfd, 0, 3510 htab->sgot->contents + off); 3511 bfd_put_32 (output_bfd, 0, 3512 htab->sgot->contents + off + 4); 3513 outrel.r_info = ELF32_R_INFO (0, R_386_TLS_DTPMOD32); 3514 loc = htab->srelgot->contents; 3515 loc += htab->srelgot->reloc_count++ * sizeof (Elf32_External_Rel); 3516 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc); 3517 htab->tls_ldm_got.offset |= 1; 3518 } 3519 relocation = htab->sgot->output_section->vma 3520 + htab->sgot->output_offset + off 3521 - htab->sgotplt->output_section->vma 3522 - htab->sgotplt->output_offset; 3523 unresolved_reloc = FALSE; 3524 break; 3525 3526 case R_386_TLS_LDO_32: 3527 if (info->shared || (input_section->flags & SEC_CODE) == 0) 3528 relocation -= dtpoff_base (info); 3529 else 3530 /* When converting LDO to LE, we must negate. */ 3531 relocation = -tpoff (info, relocation); 3532 break; 3533 3534 case R_386_TLS_LE_32: 3535 case R_386_TLS_LE: 3536 if (info->shared) 3537 { 3538 Elf_Internal_Rela outrel; 3539 asection *sreloc; 3540 bfd_byte *loc; 3541 int indx; 3542 3543 outrel.r_offset = rel->r_offset 3544 + input_section->output_section->vma 3545 + input_section->output_offset; 3546 if (h != NULL && h->dynindx != -1) 3547 indx = h->dynindx; 3548 else 3549 indx = 0; 3550 if (r_type == R_386_TLS_LE_32) 3551 outrel.r_info = ELF32_R_INFO (indx, R_386_TLS_TPOFF32); 3552 else 3553 outrel.r_info = ELF32_R_INFO (indx, R_386_TLS_TPOFF); 3554 sreloc = elf_section_data (input_section)->sreloc; 3555 if (sreloc == NULL) 3556 abort (); 3557 loc = sreloc->contents; 3558 loc += sreloc->reloc_count++ * sizeof (Elf32_External_Rel); 3559 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc); 3560 if (indx) 3561 continue; 3562 else if (r_type == R_386_TLS_LE_32) 3563 relocation = dtpoff_base (info) - relocation; 3564 else 3565 relocation -= dtpoff_base (info); 3566 } 3567 else if (r_type == R_386_TLS_LE_32) 3568 relocation = tpoff (info, relocation); 3569 else 3570 relocation = -tpoff (info, relocation); 3571 break; 3572 3573 default: 3574 break; 3575 } 3576 3577 /* Dynamic relocs are not propagated for SEC_DEBUGGING sections 3578 because such sections are not SEC_ALLOC and thus ld.so will 3579 not process them. */ 3580 if (unresolved_reloc 3581 && !((input_section->flags & SEC_DEBUGGING) != 0 3582 && h->def_dynamic)) 3583 { 3584 (*_bfd_error_handler) 3585 (_("%B(%A+0x%lx): unresolvable %s relocation against symbol `%s'"), 3586 input_bfd, 3587 input_section, 3588 (long) rel->r_offset, 3589 howto->name, 3590 h->root.root.string); 3591 return FALSE; 3592 } 3593 3594 r = _bfd_final_link_relocate (howto, input_bfd, input_section, 3595 contents, rel->r_offset, 3596 relocation, 0); 3597 3598 if (r != bfd_reloc_ok) 3599 { 3600 const char *name; 3601 3602 if (h != NULL) 3603 name = h->root.root.string; 3604 else 3605 { 3606 name = bfd_elf_string_from_elf_section (input_bfd, 3607 symtab_hdr->sh_link, 3608 sym->st_name); 3609 if (name == NULL) 3610 return FALSE; 3611 if (*name == '\0') 3612 name = bfd_section_name (input_bfd, sec); 3613 } 3614 3615 if (r == bfd_reloc_overflow) 3616 { 3617 if (! ((*info->callbacks->reloc_overflow) 3618 (info, (h ? &h->root : NULL), name, howto->name, 3619 (bfd_vma) 0, input_bfd, input_section, 3620 rel->r_offset))) 3621 return FALSE; 3622 } 3623 else 3624 { 3625 (*_bfd_error_handler) 3626 (_("%B(%A+0x%lx): reloc against `%s': error %d"), 3627 input_bfd, input_section, 3628 (long) rel->r_offset, name, (int) r); 3629 return FALSE; 3630 } 3631 } 3632 } 3633 3634 return TRUE; 3635 } 3636 3637 /* Finish up dynamic symbol handling. We set the contents of various 3638 dynamic sections here. */ 3639 3640 static bfd_boolean 3641 elf_i386_finish_dynamic_symbol (bfd *output_bfd, 3642 struct bfd_link_info *info, 3643 struct elf_link_hash_entry *h, 3644 Elf_Internal_Sym *sym) 3645 { 3646 struct elf_i386_link_hash_table *htab; 3647 3648 htab = elf_i386_hash_table (info); 3649 3650 if (h->plt.offset != (bfd_vma) -1) 3651 { 3652 bfd_vma plt_index; 3653 bfd_vma got_offset; 3654 Elf_Internal_Rela rel; 3655 bfd_byte *loc; 3656 3657 /* This symbol has an entry in the procedure linkage table. Set 3658 it up. */ 3659 3660 if (h->dynindx == -1 3661 || htab->splt == NULL 3662 || htab->sgotplt == NULL 3663 || htab->srelplt == NULL) 3664 abort (); 3665 3666 /* Get the index in the procedure linkage table which 3667 corresponds to this symbol. This is the index of this symbol 3668 in all the symbols for which we are making plt entries. The 3669 first entry in the procedure linkage table is reserved. */ 3670 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1; 3671 3672 /* Get the offset into the .got table of the entry that 3673 corresponds to this function. Each .got entry is 4 bytes. 3674 The first three are reserved. */ 3675 got_offset = (plt_index + 3) * 4; 3676 3677 /* Fill in the entry in the procedure linkage table. */ 3678 if (! info->shared) 3679 { 3680 memcpy (htab->splt->contents + h->plt.offset, elf_i386_plt_entry, 3681 PLT_ENTRY_SIZE); 3682 bfd_put_32 (output_bfd, 3683 (htab->sgotplt->output_section->vma 3684 + htab->sgotplt->output_offset 3685 + got_offset), 3686 htab->splt->contents + h->plt.offset + 2); 3687 3688 if (htab->is_vxworks) 3689 { 3690 int s, k, reloc_index; 3691 3692 /* Create the R_386_32 relocation referencing the GOT 3693 for this PLT entry. */ 3694 3695 /* S: Current slot number (zero-based). */ 3696 s = (h->plt.offset - PLT_ENTRY_SIZE) / PLT_ENTRY_SIZE; 3697 /* K: Number of relocations for PLTResolve. */ 3698 if (info->shared) 3699 k = PLTRESOLVE_RELOCS_SHLIB; 3700 else 3701 k = PLTRESOLVE_RELOCS; 3702 /* Skip the PLTresolve relocations, and the relocations for 3703 the other PLT slots. */ 3704 reloc_index = k + s * PLT_NON_JUMP_SLOT_RELOCS; 3705 loc = (htab->srelplt2->contents + reloc_index 3706 * sizeof (Elf32_External_Rel)); 3707 3708 rel.r_offset = (htab->splt->output_section->vma 3709 + htab->splt->output_offset 3710 + h->plt.offset + 2), 3711 rel.r_info = ELF32_R_INFO (htab->elf.hgot->indx, R_386_32); 3712 bfd_elf32_swap_reloc_out (output_bfd, &rel, loc); 3713 3714 /* Create the R_386_32 relocation referencing the beginning of 3715 the PLT for this GOT entry. */ 3716 rel.r_offset = (htab->sgotplt->output_section->vma 3717 + htab->sgotplt->output_offset 3718 + got_offset); 3719 rel.r_info = ELF32_R_INFO (htab->elf.hplt->indx, R_386_32); 3720 bfd_elf32_swap_reloc_out (output_bfd, &rel, 3721 loc + sizeof (Elf32_External_Rel)); 3722 } 3723 } 3724 else 3725 { 3726 memcpy (htab->splt->contents + h->plt.offset, elf_i386_pic_plt_entry, 3727 PLT_ENTRY_SIZE); 3728 bfd_put_32 (output_bfd, got_offset, 3729 htab->splt->contents + h->plt.offset + 2); 3730 } 3731 3732 bfd_put_32 (output_bfd, plt_index * sizeof (Elf32_External_Rel), 3733 htab->splt->contents + h->plt.offset + 7); 3734 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE), 3735 htab->splt->contents + h->plt.offset + 12); 3736 3737 /* Fill in the entry in the global offset table. */ 3738 bfd_put_32 (output_bfd, 3739 (htab->splt->output_section->vma 3740 + htab->splt->output_offset 3741 + h->plt.offset 3742 + 6), 3743 htab->sgotplt->contents + got_offset); 3744 3745 /* Fill in the entry in the .rel.plt section. */ 3746 rel.r_offset = (htab->sgotplt->output_section->vma 3747 + htab->sgotplt->output_offset 3748 + got_offset); 3749 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_JUMP_SLOT); 3750 loc = htab->srelplt->contents + plt_index * sizeof (Elf32_External_Rel); 3751 bfd_elf32_swap_reloc_out (output_bfd, &rel, loc); 3752 3753 if (!h->def_regular) 3754 { 3755 /* Mark the symbol as undefined, rather than as defined in 3756 the .plt section. Leave the value if there were any 3757 relocations where pointer equality matters (this is a clue 3758 for the dynamic linker, to make function pointer 3759 comparisons work between an application and shared 3760 library), otherwise set it to zero. If a function is only 3761 called from a binary, there is no need to slow down 3762 shared libraries because of that. */ 3763 sym->st_shndx = SHN_UNDEF; 3764 if (!h->pointer_equality_needed) 3765 sym->st_value = 0; 3766 } 3767 } 3768 3769 if (h->got.offset != (bfd_vma) -1 3770 && ! GOT_TLS_GD_ANY_P (elf_i386_hash_entry(h)->tls_type) 3771 && (elf_i386_hash_entry(h)->tls_type & GOT_TLS_IE) == 0) 3772 { 3773 Elf_Internal_Rela rel; 3774 bfd_byte *loc; 3775 3776 /* This symbol has an entry in the global offset table. Set it 3777 up. */ 3778 3779 if (htab->sgot == NULL || htab->srelgot == NULL) 3780 abort (); 3781 3782 rel.r_offset = (htab->sgot->output_section->vma 3783 + htab->sgot->output_offset 3784 + (h->got.offset & ~(bfd_vma) 1)); 3785 3786 /* If this is a static link, or it is a -Bsymbolic link and the 3787 symbol is defined locally or was forced to be local because 3788 of a version file, we just want to emit a RELATIVE reloc. 3789 The entry in the global offset table will already have been 3790 initialized in the relocate_section function. */ 3791 if (info->shared 3792 && SYMBOL_REFERENCES_LOCAL (info, h)) 3793 { 3794 BFD_ASSERT((h->got.offset & 1) != 0); 3795 rel.r_info = ELF32_R_INFO (0, R_386_RELATIVE); 3796 } 3797 else 3798 { 3799 BFD_ASSERT((h->got.offset & 1) == 0); 3800 bfd_put_32 (output_bfd, (bfd_vma) 0, 3801 htab->sgot->contents + h->got.offset); 3802 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_GLOB_DAT); 3803 } 3804 3805 loc = htab->srelgot->contents; 3806 loc += htab->srelgot->reloc_count++ * sizeof (Elf32_External_Rel); 3807 bfd_elf32_swap_reloc_out (output_bfd, &rel, loc); 3808 } 3809 3810 if (h->needs_copy) 3811 { 3812 Elf_Internal_Rela rel; 3813 bfd_byte *loc; 3814 3815 /* This symbol needs a copy reloc. Set it up. */ 3816 3817 if (h->dynindx == -1 3818 || (h->root.type != bfd_link_hash_defined 3819 && h->root.type != bfd_link_hash_defweak) 3820 || htab->srelbss == NULL) 3821 abort (); 3822 3823 rel.r_offset = (h->root.u.def.value 3824 + h->root.u.def.section->output_section->vma 3825 + h->root.u.def.section->output_offset); 3826 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_COPY); 3827 loc = htab->srelbss->contents; 3828 loc += htab->srelbss->reloc_count++ * sizeof (Elf32_External_Rel); 3829 bfd_elf32_swap_reloc_out (output_bfd, &rel, loc); 3830 } 3831 3832 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. 3833 On VxWorks, the _GLOBAL_OFFSET_TABLE_ symbol is not absolute: it 3834 is relative to the ".got" section. */ 3835 if (strcmp (h->root.root.string, "_DYNAMIC") == 0 3836 || (!htab->is_vxworks && h == htab->elf.hgot)) 3837 sym->st_shndx = SHN_ABS; 3838 3839 return TRUE; 3840 } 3841 3842 /* Used to decide how to sort relocs in an optimal manner for the 3843 dynamic linker, before writing them out. */ 3844 3845 static enum elf_reloc_type_class 3846 elf_i386_reloc_type_class (const Elf_Internal_Rela *rela) 3847 { 3848 switch (ELF32_R_TYPE (rela->r_info)) 3849 { 3850 case R_386_RELATIVE: 3851 return reloc_class_relative; 3852 case R_386_JUMP_SLOT: 3853 return reloc_class_plt; 3854 case R_386_COPY: 3855 return reloc_class_copy; 3856 default: 3857 return reloc_class_normal; 3858 } 3859 } 3860 3861 /* Finish up the dynamic sections. */ 3862 3863 static bfd_boolean 3864 elf_i386_finish_dynamic_sections (bfd *output_bfd, 3865 struct bfd_link_info *info) 3866 { 3867 struct elf_i386_link_hash_table *htab; 3868 bfd *dynobj; 3869 asection *sdyn; 3870 3871 htab = elf_i386_hash_table (info); 3872 dynobj = htab->elf.dynobj; 3873 sdyn = bfd_get_section_by_name (dynobj, ".dynamic"); 3874 3875 if (htab->elf.dynamic_sections_created) 3876 { 3877 Elf32_External_Dyn *dyncon, *dynconend; 3878 3879 if (sdyn == NULL || htab->sgot == NULL) 3880 abort (); 3881 3882 dyncon = (Elf32_External_Dyn *) sdyn->contents; 3883 dynconend = (Elf32_External_Dyn *) (sdyn->contents + sdyn->size); 3884 for (; dyncon < dynconend; dyncon++) 3885 { 3886 Elf_Internal_Dyn dyn; 3887 asection *s; 3888 3889 bfd_elf32_swap_dyn_in (dynobj, dyncon, &dyn); 3890 3891 switch (dyn.d_tag) 3892 { 3893 default: 3894 if (htab->is_vxworks 3895 && elf_vxworks_finish_dynamic_entry (output_bfd, &dyn)) 3896 break; 3897 continue; 3898 3899 case DT_PLTGOT: 3900 s = htab->sgotplt; 3901 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset; 3902 break; 3903 3904 case DT_JMPREL: 3905 s = htab->srelplt; 3906 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset; 3907 break; 3908 3909 case DT_PLTRELSZ: 3910 s = htab->srelplt; 3911 dyn.d_un.d_val = s->size; 3912 break; 3913 3914 case DT_RELSZ: 3915 /* My reading of the SVR4 ABI indicates that the 3916 procedure linkage table relocs (DT_JMPREL) should be 3917 included in the overall relocs (DT_REL). This is 3918 what Solaris does. However, UnixWare can not handle 3919 that case. Therefore, we override the DT_RELSZ entry 3920 here to make it not include the JMPREL relocs. */ 3921 s = htab->srelplt; 3922 if (s == NULL) 3923 continue; 3924 dyn.d_un.d_val -= s->size; 3925 break; 3926 3927 case DT_REL: 3928 /* We may not be using the standard ELF linker script. 3929 If .rel.plt is the first .rel section, we adjust 3930 DT_REL to not include it. */ 3931 s = htab->srelplt; 3932 if (s == NULL) 3933 continue; 3934 if (dyn.d_un.d_ptr != s->output_section->vma + s->output_offset) 3935 continue; 3936 dyn.d_un.d_ptr += s->size; 3937 break; 3938 } 3939 3940 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon); 3941 } 3942 3943 /* Fill in the first entry in the procedure linkage table. */ 3944 if (htab->splt && htab->splt->size > 0) 3945 { 3946 if (info->shared) 3947 { 3948 memcpy (htab->splt->contents, elf_i386_pic_plt0_entry, 3949 sizeof (elf_i386_pic_plt0_entry)); 3950 memset (htab->splt->contents + sizeof (elf_i386_pic_plt0_entry), 3951 htab->plt0_pad_byte, 3952 PLT_ENTRY_SIZE - sizeof (elf_i386_pic_plt0_entry)); 3953 } 3954 else 3955 { 3956 memcpy (htab->splt->contents, elf_i386_plt0_entry, 3957 sizeof(elf_i386_plt0_entry)); 3958 memset (htab->splt->contents + sizeof (elf_i386_plt0_entry), 3959 htab->plt0_pad_byte, 3960 PLT_ENTRY_SIZE - sizeof (elf_i386_plt0_entry)); 3961 bfd_put_32 (output_bfd, 3962 (htab->sgotplt->output_section->vma 3963 + htab->sgotplt->output_offset 3964 + 4), 3965 htab->splt->contents + 2); 3966 bfd_put_32 (output_bfd, 3967 (htab->sgotplt->output_section->vma 3968 + htab->sgotplt->output_offset 3969 + 8), 3970 htab->splt->contents + 8); 3971 3972 if (htab->is_vxworks) 3973 { 3974 Elf_Internal_Rela rel; 3975 3976 /* Generate a relocation for _GLOBAL_OFFSET_TABLE_ + 4. 3977 On IA32 we use REL relocations so the addend goes in 3978 the PLT directly. */ 3979 rel.r_offset = (htab->splt->output_section->vma 3980 + htab->splt->output_offset 3981 + 2); 3982 rel.r_info = ELF32_R_INFO (htab->elf.hgot->indx, R_386_32); 3983 bfd_elf32_swap_reloc_out (output_bfd, &rel, 3984 htab->srelplt2->contents); 3985 /* Generate a relocation for _GLOBAL_OFFSET_TABLE_ + 8. */ 3986 rel.r_offset = (htab->splt->output_section->vma 3987 + htab->splt->output_offset 3988 + 8); 3989 rel.r_info = ELF32_R_INFO (htab->elf.hgot->indx, R_386_32); 3990 bfd_elf32_swap_reloc_out (output_bfd, &rel, 3991 htab->srelplt2->contents + 3992 sizeof (Elf32_External_Rel)); 3993 } 3994 } 3995 3996 /* UnixWare sets the entsize of .plt to 4, although that doesn't 3997 really seem like the right value. */ 3998 elf_section_data (htab->splt->output_section) 3999 ->this_hdr.sh_entsize = 4; 4000 4001 /* Correct the .rel.plt.unloaded relocations. */ 4002 if (htab->is_vxworks && !info->shared) 4003 { 4004 int num_plts = (htab->splt->size / PLT_ENTRY_SIZE) - 1; 4005 unsigned char *p; 4006 4007 p = htab->srelplt2->contents; 4008 if (info->shared) 4009 p += PLTRESOLVE_RELOCS_SHLIB * sizeof (Elf32_External_Rel); 4010 else 4011 p += PLTRESOLVE_RELOCS * sizeof (Elf32_External_Rel); 4012 4013 for (; num_plts; num_plts--) 4014 { 4015 Elf_Internal_Rela rel; 4016 bfd_elf32_swap_reloc_in (output_bfd, p, &rel); 4017 rel.r_info = ELF32_R_INFO (htab->elf.hgot->indx, R_386_32); 4018 bfd_elf32_swap_reloc_out (output_bfd, &rel, p); 4019 p += sizeof (Elf32_External_Rel); 4020 4021 bfd_elf32_swap_reloc_in (output_bfd, p, &rel); 4022 rel.r_info = ELF32_R_INFO (htab->elf.hplt->indx, R_386_32); 4023 bfd_elf32_swap_reloc_out (output_bfd, &rel, p); 4024 p += sizeof (Elf32_External_Rel); 4025 } 4026 } 4027 } 4028 } 4029 4030 if (htab->sgotplt) 4031 { 4032 /* Fill in the first three entries in the global offset table. */ 4033 if (htab->sgotplt->size > 0) 4034 { 4035 bfd_put_32 (output_bfd, 4036 (sdyn == NULL ? 0 4037 : sdyn->output_section->vma + sdyn->output_offset), 4038 htab->sgotplt->contents); 4039 bfd_put_32 (output_bfd, 0, htab->sgotplt->contents + 4); 4040 bfd_put_32 (output_bfd, 0, htab->sgotplt->contents + 8); 4041 } 4042 4043 elf_section_data (htab->sgotplt->output_section)->this_hdr.sh_entsize = 4; 4044 } 4045 4046 if (htab->sgot && htab->sgot->size > 0) 4047 elf_section_data (htab->sgot->output_section)->this_hdr.sh_entsize = 4; 4048 4049 return TRUE; 4050 } 4051 4052 /* Return address for Ith PLT stub in section PLT, for relocation REL 4053 or (bfd_vma) -1 if it should not be included. */ 4054 4055 static bfd_vma 4056 elf_i386_plt_sym_val (bfd_vma i, const asection *plt, 4057 const arelent *rel ATTRIBUTE_UNUSED) 4058 { 4059 return plt->vma + (i + 1) * PLT_ENTRY_SIZE; 4060 } 4061 4062 /* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */ 4063 4064 static bfd_boolean 4065 elf_i386_hash_symbol (struct elf_link_hash_entry *h) 4066 { 4067 if (h->plt.offset != (bfd_vma) -1 4068 && !h->def_regular 4069 && !h->pointer_equality_needed) 4070 return FALSE; 4071 4072 return _bfd_elf_hash_symbol (h); 4073 } 4074 4075 #define TARGET_LITTLE_SYM bfd_elf32_i386_vec 4076 #define TARGET_LITTLE_NAME "elf32-i386" 4077 #define ELF_ARCH bfd_arch_i386 4078 #define ELF_MACHINE_CODE EM_386 4079 #define ELF_MAXPAGESIZE 0x1000 4080 4081 #define elf_backend_can_gc_sections 1 4082 #define elf_backend_can_refcount 1 4083 #define elf_backend_want_got_plt 1 4084 #define elf_backend_plt_readonly 1 4085 #define elf_backend_want_plt_sym 0 4086 #define elf_backend_got_header_size 12 4087 4088 /* Support RELA for objdump of prelink objects. */ 4089 #define elf_info_to_howto elf_i386_info_to_howto_rel 4090 #define elf_info_to_howto_rel elf_i386_info_to_howto_rel 4091 4092 #define bfd_elf32_mkobject elf_i386_mkobject 4093 4094 #define bfd_elf32_bfd_is_local_label_name elf_i386_is_local_label_name 4095 #define bfd_elf32_bfd_link_hash_table_create elf_i386_link_hash_table_create 4096 #define bfd_elf32_bfd_reloc_type_lookup elf_i386_reloc_type_lookup 4097 #define bfd_elf32_bfd_reloc_name_lookup elf_i386_reloc_name_lookup 4098 4099 #define elf_backend_adjust_dynamic_symbol elf_i386_adjust_dynamic_symbol 4100 #define elf_backend_relocs_compatible _bfd_elf_relocs_compatible 4101 #define elf_backend_check_relocs elf_i386_check_relocs 4102 #define elf_backend_copy_indirect_symbol elf_i386_copy_indirect_symbol 4103 #define elf_backend_create_dynamic_sections elf_i386_create_dynamic_sections 4104 #define elf_backend_fake_sections elf_i386_fake_sections 4105 #define elf_backend_finish_dynamic_sections elf_i386_finish_dynamic_sections 4106 #define elf_backend_finish_dynamic_symbol elf_i386_finish_dynamic_symbol 4107 #define elf_backend_gc_mark_hook elf_i386_gc_mark_hook 4108 #define elf_backend_gc_sweep_hook elf_i386_gc_sweep_hook 4109 #define elf_backend_grok_prstatus elf_i386_grok_prstatus 4110 #define elf_backend_grok_psinfo elf_i386_grok_psinfo 4111 #define elf_backend_reloc_type_class elf_i386_reloc_type_class 4112 #define elf_backend_relocate_section elf_i386_relocate_section 4113 #define elf_backend_size_dynamic_sections elf_i386_size_dynamic_sections 4114 #define elf_backend_always_size_sections elf_i386_always_size_sections 4115 #define elf_backend_omit_section_dynsym \ 4116 ((bfd_boolean (*) (bfd *, struct bfd_link_info *, asection *)) bfd_true) 4117 #define elf_backend_plt_sym_val elf_i386_plt_sym_val 4118 #define elf_backend_hash_symbol elf_i386_hash_symbol 4119 4120 #include "elf32-target.h" 4121 4122 /* FreeBSD support. */ 4123 4124 #undef TARGET_LITTLE_SYM 4125 #define TARGET_LITTLE_SYM bfd_elf32_i386_freebsd_vec 4126 #undef TARGET_LITTLE_NAME 4127 #define TARGET_LITTLE_NAME "elf32-i386-freebsd" 4128 #undef ELF_OSABI 4129 #define ELF_OSABI ELFOSABI_FREEBSD 4130 4131 /* The kernel recognizes executables as valid only if they carry a 4132 "FreeBSD" label in the ELF header. So we put this label on all 4133 executables and (for simplicity) also all other object files. */ 4134 4135 static void 4136 elf_i386_post_process_headers (bfd *abfd, 4137 struct bfd_link_info *info ATTRIBUTE_UNUSED) 4138 { 4139 Elf_Internal_Ehdr *i_ehdrp; 4140 4141 i_ehdrp = elf_elfheader (abfd); 4142 4143 /* Put an ABI label supported by FreeBSD >= 4.1. */ 4144 i_ehdrp->e_ident[EI_OSABI] = get_elf_backend_data (abfd)->elf_osabi; 4145 #ifdef OLD_FREEBSD_ABI_LABEL 4146 /* The ABI label supported by FreeBSD <= 4.0 is quite nonstandard. */ 4147 memcpy (&i_ehdrp->e_ident[EI_ABIVERSION], "FreeBSD", 8); 4148 #endif 4149 } 4150 4151 #undef elf_backend_post_process_headers 4152 #define elf_backend_post_process_headers elf_i386_post_process_headers 4153 #undef elf32_bed 4154 #define elf32_bed elf32_i386_fbsd_bed 4155 4156 #include "elf32-target.h" 4157 4158 /* VxWorks support. */ 4159 4160 #undef TARGET_LITTLE_SYM 4161 #define TARGET_LITTLE_SYM bfd_elf32_i386_vxworks_vec 4162 #undef TARGET_LITTLE_NAME 4163 #define TARGET_LITTLE_NAME "elf32-i386-vxworks" 4164 #undef ELF_OSABI 4165 4166 /* Like elf_i386_link_hash_table_create but with tweaks for VxWorks. */ 4167 4168 static struct bfd_link_hash_table * 4169 elf_i386_vxworks_link_hash_table_create (bfd *abfd) 4170 { 4171 struct bfd_link_hash_table *ret; 4172 struct elf_i386_link_hash_table *htab; 4173 4174 ret = elf_i386_link_hash_table_create (abfd); 4175 if (ret) 4176 { 4177 htab = (struct elf_i386_link_hash_table *) ret; 4178 htab->is_vxworks = 1; 4179 htab->plt0_pad_byte = 0x90; 4180 } 4181 4182 return ret; 4183 } 4184 4185 4186 #undef elf_backend_relocs_compatible 4187 #undef elf_backend_post_process_headers 4188 #undef bfd_elf32_bfd_link_hash_table_create 4189 #define bfd_elf32_bfd_link_hash_table_create \ 4190 elf_i386_vxworks_link_hash_table_create 4191 #undef elf_backend_add_symbol_hook 4192 #define elf_backend_add_symbol_hook \ 4193 elf_vxworks_add_symbol_hook 4194 #undef elf_backend_link_output_symbol_hook 4195 #define elf_backend_link_output_symbol_hook \ 4196 elf_vxworks_link_output_symbol_hook 4197 #undef elf_backend_emit_relocs 4198 #define elf_backend_emit_relocs elf_vxworks_emit_relocs 4199 #undef elf_backend_final_write_processing 4200 #define elf_backend_final_write_processing \ 4201 elf_vxworks_final_write_processing 4202 4203 /* On VxWorks, we emit relocations against _PROCEDURE_LINKAGE_TABLE_, so 4204 define it. */ 4205 #undef elf_backend_want_plt_sym 4206 #define elf_backend_want_plt_sym 1 4207 4208 #undef elf32_bed 4209 #define elf32_bed elf32_i386_vxworks_bed 4210 4211 #include "elf32-target.h" 4212