1 /* ELF executable support for BFD. 2 Copyright (C) 1991-2017 Free Software Foundation, Inc. 3 4 Written by Fred Fish @ Cygnus Support, from information published 5 in "UNIX System V Release 4, Programmers Guide: ANSI C and 6 Programming Support Tools". Sufficient support for gdb. 7 8 Rewritten by Mark Eichin @ Cygnus Support, from information 9 published in "System V Application Binary Interface", chapters 4 10 and 5, as well as the various "Processor Supplement" documents 11 derived from it. Added support for assembler and other object file 12 utilities. Further work done by Ken Raeburn (Cygnus Support), Michael 13 Meissner (Open Software Foundation), and Peter Hoogenboom (University 14 of Utah) to finish and extend this. 15 16 This file is part of BFD, the Binary File Descriptor library. 17 18 This program is free software; you can redistribute it and/or modify 19 it under the terms of the GNU General Public License as published by 20 the Free Software Foundation; either version 3 of the License, or 21 (at your option) any later version. 22 23 This program is distributed in the hope that it will be useful, 24 but WITHOUT ANY WARRANTY; without even the implied warranty of 25 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 26 GNU General Public License for more details. 27 28 You should have received a copy of the GNU General Public License 29 along with this program; if not, write to the Free Software 30 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 31 MA 02110-1301, USA. */ 32 33 34 /* Problems and other issues to resolve. 35 36 (1) BFD expects there to be some fixed number of "sections" in 37 the object file. I.E. there is a "section_count" variable in the 38 bfd structure which contains the number of sections. However, ELF 39 supports multiple "views" of a file. In particular, with current 40 implementations, executable files typically have two tables, a 41 program header table and a section header table, both of which 42 partition the executable. 43 44 In ELF-speak, the "linking view" of the file uses the section header 45 table to access "sections" within the file, and the "execution view" 46 uses the program header table to access "segments" within the file. 47 "Segments" typically may contain all the data from one or more 48 "sections". 49 50 Note that the section header table is optional in ELF executables, 51 but it is this information that is most useful to gdb. If the 52 section header table is missing, then gdb should probably try 53 to make do with the program header table. (FIXME) 54 55 (2) The code in this file is compiled twice, once in 32-bit mode and 56 once in 64-bit mode. More of it should be made size-independent 57 and moved into elf.c. 58 59 (3) ELF section symbols are handled rather sloppily now. This should 60 be cleaned up, and ELF section symbols reconciled with BFD section 61 symbols. 62 63 (4) We need a published spec for 64-bit ELF. We've got some stuff here 64 that we're using for SPARC V9 64-bit chips, but don't assume that 65 it's cast in stone. 66 */ 67 68 #include "sysdep.h" 69 #include "bfd.h" 70 #include "libiberty.h" 71 #include "bfdlink.h" 72 #include "libbfd.h" 73 #include "elf-bfd.h" 74 #include "libiberty.h" 75 76 /* Renaming structures, typedefs, macros and functions to be size-specific. */ 77 #define Elf_External_Ehdr NAME(Elf,External_Ehdr) 78 #define Elf_External_Sym NAME(Elf,External_Sym) 79 #define Elf_External_Shdr NAME(Elf,External_Shdr) 80 #define Elf_External_Phdr NAME(Elf,External_Phdr) 81 #define Elf_External_Rel NAME(Elf,External_Rel) 82 #define Elf_External_Rela NAME(Elf,External_Rela) 83 #define Elf_External_Dyn NAME(Elf,External_Dyn) 84 85 #define elf_core_file_failing_command NAME(bfd_elf,core_file_failing_command) 86 #define elf_core_file_failing_signal NAME(bfd_elf,core_file_failing_signal) 87 #define elf_core_file_matches_executable_p \ 88 NAME(bfd_elf,core_file_matches_executable_p) 89 #define elf_core_file_pid NAME(bfd_elf,core_file_pid) 90 #define elf_object_p NAME(bfd_elf,object_p) 91 #define elf_core_file_p NAME(bfd_elf,core_file_p) 92 #define elf_get_symtab_upper_bound NAME(bfd_elf,get_symtab_upper_bound) 93 #define elf_get_dynamic_symtab_upper_bound \ 94 NAME(bfd_elf,get_dynamic_symtab_upper_bound) 95 #define elf_swap_reloc_in NAME(bfd_elf,swap_reloc_in) 96 #define elf_swap_reloca_in NAME(bfd_elf,swap_reloca_in) 97 #define elf_swap_reloc_out NAME(bfd_elf,swap_reloc_out) 98 #define elf_swap_reloca_out NAME(bfd_elf,swap_reloca_out) 99 #define elf_swap_symbol_in NAME(bfd_elf,swap_symbol_in) 100 #define elf_swap_symbol_out NAME(bfd_elf,swap_symbol_out) 101 #define elf_swap_phdr_in NAME(bfd_elf,swap_phdr_in) 102 #define elf_swap_phdr_out NAME(bfd_elf,swap_phdr_out) 103 #define elf_swap_dyn_in NAME(bfd_elf,swap_dyn_in) 104 #define elf_swap_dyn_out NAME(bfd_elf,swap_dyn_out) 105 #define elf_get_reloc_upper_bound NAME(bfd_elf,get_reloc_upper_bound) 106 #define elf_canonicalize_reloc NAME(bfd_elf,canonicalize_reloc) 107 #define elf_slurp_symbol_table NAME(bfd_elf,slurp_symbol_table) 108 #define elf_canonicalize_symtab NAME(bfd_elf,canonicalize_symtab) 109 #define elf_canonicalize_dynamic_symtab \ 110 NAME(bfd_elf,canonicalize_dynamic_symtab) 111 #define elf_get_synthetic_symtab \ 112 NAME(bfd_elf,get_synthetic_symtab) 113 #define elf_make_empty_symbol NAME(bfd_elf,make_empty_symbol) 114 #define elf_get_symbol_info NAME(bfd_elf,get_symbol_info) 115 #define elf_get_lineno NAME(bfd_elf,get_lineno) 116 #define elf_set_arch_mach NAME(bfd_elf,set_arch_mach) 117 #define elf_find_nearest_line NAME(bfd_elf,find_nearest_line) 118 #define elf_sizeof_headers NAME(bfd_elf,sizeof_headers) 119 #define elf_set_section_contents NAME(bfd_elf,set_section_contents) 120 #define elf_no_info_to_howto NAME(bfd_elf,no_info_to_howto) 121 #define elf_no_info_to_howto_rel NAME(bfd_elf,no_info_to_howto_rel) 122 #define elf_find_section NAME(bfd_elf,find_section) 123 #define elf_write_shdrs_and_ehdr NAME(bfd_elf,write_shdrs_and_ehdr) 124 #define elf_write_out_phdrs NAME(bfd_elf,write_out_phdrs) 125 #define elf_checksum_contents NAME(bfd_elf,checksum_contents) 126 #define elf_write_relocs NAME(bfd_elf,write_relocs) 127 #define elf_slurp_reloc_table NAME(bfd_elf,slurp_reloc_table) 128 129 #if ARCH_SIZE == 64 130 #define ELF_R_INFO(X,Y) ELF64_R_INFO(X,Y) 131 #define ELF_R_SYM(X) ELF64_R_SYM(X) 132 #define ELF_R_TYPE(X) ELF64_R_TYPE(X) 133 #define ELFCLASS ELFCLASS64 134 #define FILE_ALIGN 8 135 #define LOG_FILE_ALIGN 3 136 #endif 137 #if ARCH_SIZE == 32 138 #define ELF_R_INFO(X,Y) ELF32_R_INFO(X,Y) 139 #define ELF_R_SYM(X) ELF32_R_SYM(X) 140 #define ELF_R_TYPE(X) ELF32_R_TYPE(X) 141 #define ELFCLASS ELFCLASS32 142 #define FILE_ALIGN 4 143 #define LOG_FILE_ALIGN 2 144 #endif 145 146 #if DEBUG & 2 147 static void elf_debug_section (int, Elf_Internal_Shdr *); 148 #endif 149 #if DEBUG & 1 150 static void elf_debug_file (Elf_Internal_Ehdr *); 151 #endif 152 153 /* Structure swapping routines */ 154 155 /* Should perhaps use put_offset, put_word, etc. For now, the two versions 156 can be handled by explicitly specifying 32 bits or "the long type". */ 157 #if ARCH_SIZE == 64 158 #define H_PUT_WORD H_PUT_64 159 #define H_PUT_SIGNED_WORD H_PUT_S64 160 #define H_GET_WORD H_GET_64 161 #define H_GET_SIGNED_WORD H_GET_S64 162 #endif 163 #if ARCH_SIZE == 32 164 #define H_PUT_WORD H_PUT_32 165 #define H_PUT_SIGNED_WORD H_PUT_S32 166 #define H_GET_WORD H_GET_32 167 #define H_GET_SIGNED_WORD H_GET_S32 168 #endif 169 170 /* Translate an ELF symbol in external format into an ELF symbol in internal 171 format. */ 172 173 bfd_boolean 174 elf_swap_symbol_in (bfd *abfd, 175 const void *psrc, 176 const void *pshn, 177 Elf_Internal_Sym *dst) 178 { 179 const Elf_External_Sym *src = (const Elf_External_Sym *) psrc; 180 const Elf_External_Sym_Shndx *shndx = (const Elf_External_Sym_Shndx *) pshn; 181 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma; 182 183 dst->st_name = H_GET_32 (abfd, src->st_name); 184 if (signed_vma) 185 dst->st_value = H_GET_SIGNED_WORD (abfd, src->st_value); 186 else 187 dst->st_value = H_GET_WORD (abfd, src->st_value); 188 dst->st_size = H_GET_WORD (abfd, src->st_size); 189 dst->st_info = H_GET_8 (abfd, src->st_info); 190 dst->st_other = H_GET_8 (abfd, src->st_other); 191 dst->st_shndx = H_GET_16 (abfd, src->st_shndx); 192 if (dst->st_shndx == (SHN_XINDEX & 0xffff)) 193 { 194 if (shndx == NULL) 195 return FALSE; 196 dst->st_shndx = H_GET_32 (abfd, shndx->est_shndx); 197 } 198 else if (dst->st_shndx >= (SHN_LORESERVE & 0xffff)) 199 dst->st_shndx += SHN_LORESERVE - (SHN_LORESERVE & 0xffff); 200 dst->st_target_internal = 0; 201 return TRUE; 202 } 203 204 /* Translate an ELF symbol in internal format into an ELF symbol in external 205 format. */ 206 207 void 208 elf_swap_symbol_out (bfd *abfd, 209 const Elf_Internal_Sym *src, 210 void *cdst, 211 void *shndx) 212 { 213 unsigned int tmp; 214 Elf_External_Sym *dst = (Elf_External_Sym *) cdst; 215 H_PUT_32 (abfd, src->st_name, dst->st_name); 216 H_PUT_WORD (abfd, src->st_value, dst->st_value); 217 H_PUT_WORD (abfd, src->st_size, dst->st_size); 218 H_PUT_8 (abfd, src->st_info, dst->st_info); 219 H_PUT_8 (abfd, src->st_other, dst->st_other); 220 tmp = src->st_shndx; 221 if (tmp >= (SHN_LORESERVE & 0xffff) && tmp < SHN_LORESERVE) 222 { 223 if (shndx == NULL) 224 abort (); 225 H_PUT_32 (abfd, tmp, shndx); 226 tmp = SHN_XINDEX & 0xffff; 227 } 228 H_PUT_16 (abfd, tmp, dst->st_shndx); 229 } 230 231 /* Translate an ELF file header in external format into an ELF file header in 232 internal format. */ 233 234 static void 235 elf_swap_ehdr_in (bfd *abfd, 236 const Elf_External_Ehdr *src, 237 Elf_Internal_Ehdr *dst) 238 { 239 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma; 240 memcpy (dst->e_ident, src->e_ident, EI_NIDENT); 241 dst->e_type = H_GET_16 (abfd, src->e_type); 242 dst->e_machine = H_GET_16 (abfd, src->e_machine); 243 dst->e_version = H_GET_32 (abfd, src->e_version); 244 if (signed_vma) 245 dst->e_entry = H_GET_SIGNED_WORD (abfd, src->e_entry); 246 else 247 dst->e_entry = H_GET_WORD (abfd, src->e_entry); 248 dst->e_phoff = H_GET_WORD (abfd, src->e_phoff); 249 dst->e_shoff = H_GET_WORD (abfd, src->e_shoff); 250 dst->e_flags = H_GET_32 (abfd, src->e_flags); 251 dst->e_ehsize = H_GET_16 (abfd, src->e_ehsize); 252 dst->e_phentsize = H_GET_16 (abfd, src->e_phentsize); 253 dst->e_phnum = H_GET_16 (abfd, src->e_phnum); 254 dst->e_shentsize = H_GET_16 (abfd, src->e_shentsize); 255 dst->e_shnum = H_GET_16 (abfd, src->e_shnum); 256 dst->e_shstrndx = H_GET_16 (abfd, src->e_shstrndx); 257 } 258 259 /* Translate an ELF file header in internal format into an ELF file header in 260 external format. */ 261 262 static void 263 elf_swap_ehdr_out (bfd *abfd, 264 const Elf_Internal_Ehdr *src, 265 Elf_External_Ehdr *dst) 266 { 267 unsigned int tmp; 268 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma; 269 memcpy (dst->e_ident, src->e_ident, EI_NIDENT); 270 /* note that all elements of dst are *arrays of unsigned char* already... */ 271 H_PUT_16 (abfd, src->e_type, dst->e_type); 272 H_PUT_16 (abfd, src->e_machine, dst->e_machine); 273 H_PUT_32 (abfd, src->e_version, dst->e_version); 274 if (signed_vma) 275 H_PUT_SIGNED_WORD (abfd, src->e_entry, dst->e_entry); 276 else 277 H_PUT_WORD (abfd, src->e_entry, dst->e_entry); 278 H_PUT_WORD (abfd, src->e_phoff, dst->e_phoff); 279 H_PUT_WORD (abfd, src->e_shoff, dst->e_shoff); 280 H_PUT_32 (abfd, src->e_flags, dst->e_flags); 281 H_PUT_16 (abfd, src->e_ehsize, dst->e_ehsize); 282 H_PUT_16 (abfd, src->e_phentsize, dst->e_phentsize); 283 tmp = src->e_phnum; 284 if (tmp > PN_XNUM) 285 tmp = PN_XNUM; 286 H_PUT_16 (abfd, tmp, dst->e_phnum); 287 H_PUT_16 (abfd, src->e_shentsize, dst->e_shentsize); 288 tmp = src->e_shnum; 289 if (tmp >= (SHN_LORESERVE & 0xffff)) 290 tmp = SHN_UNDEF; 291 H_PUT_16 (abfd, tmp, dst->e_shnum); 292 tmp = src->e_shstrndx; 293 if (tmp >= (SHN_LORESERVE & 0xffff)) 294 tmp = SHN_XINDEX & 0xffff; 295 H_PUT_16 (abfd, tmp, dst->e_shstrndx); 296 } 297 298 /* Translate an ELF section header table entry in external format into an 299 ELF section header table entry in internal format. */ 300 301 static void 302 elf_swap_shdr_in (bfd *abfd, 303 const Elf_External_Shdr *src, 304 Elf_Internal_Shdr *dst) 305 { 306 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma; 307 308 dst->sh_name = H_GET_32 (abfd, src->sh_name); 309 dst->sh_type = H_GET_32 (abfd, src->sh_type); 310 dst->sh_flags = H_GET_WORD (abfd, src->sh_flags); 311 if (signed_vma) 312 dst->sh_addr = H_GET_SIGNED_WORD (abfd, src->sh_addr); 313 else 314 dst->sh_addr = H_GET_WORD (abfd, src->sh_addr); 315 dst->sh_offset = H_GET_WORD (abfd, src->sh_offset); 316 dst->sh_size = H_GET_WORD (abfd, src->sh_size); 317 dst->sh_link = H_GET_32 (abfd, src->sh_link); 318 dst->sh_info = H_GET_32 (abfd, src->sh_info); 319 dst->sh_addralign = H_GET_WORD (abfd, src->sh_addralign); 320 dst->sh_entsize = H_GET_WORD (abfd, src->sh_entsize); 321 dst->bfd_section = NULL; 322 dst->contents = NULL; 323 } 324 325 /* Translate an ELF section header table entry in internal format into an 326 ELF section header table entry in external format. */ 327 328 static void 329 elf_swap_shdr_out (bfd *abfd, 330 const Elf_Internal_Shdr *src, 331 Elf_External_Shdr *dst) 332 { 333 /* note that all elements of dst are *arrays of unsigned char* already... */ 334 H_PUT_32 (abfd, src->sh_name, dst->sh_name); 335 H_PUT_32 (abfd, src->sh_type, dst->sh_type); 336 H_PUT_WORD (abfd, src->sh_flags, dst->sh_flags); 337 H_PUT_WORD (abfd, src->sh_addr, dst->sh_addr); 338 H_PUT_WORD (abfd, src->sh_offset, dst->sh_offset); 339 H_PUT_WORD (abfd, src->sh_size, dst->sh_size); 340 H_PUT_32 (abfd, src->sh_link, dst->sh_link); 341 H_PUT_32 (abfd, src->sh_info, dst->sh_info); 342 H_PUT_WORD (abfd, src->sh_addralign, dst->sh_addralign); 343 H_PUT_WORD (abfd, src->sh_entsize, dst->sh_entsize); 344 } 345 346 /* Translate an ELF program header table entry in external format into an 347 ELF program header table entry in internal format. */ 348 349 void 350 elf_swap_phdr_in (bfd *abfd, 351 const Elf_External_Phdr *src, 352 Elf_Internal_Phdr *dst) 353 { 354 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma; 355 356 dst->p_type = H_GET_32 (abfd, src->p_type); 357 dst->p_flags = H_GET_32 (abfd, src->p_flags); 358 dst->p_offset = H_GET_WORD (abfd, src->p_offset); 359 if (signed_vma) 360 { 361 dst->p_vaddr = H_GET_SIGNED_WORD (abfd, src->p_vaddr); 362 dst->p_paddr = H_GET_SIGNED_WORD (abfd, src->p_paddr); 363 } 364 else 365 { 366 dst->p_vaddr = H_GET_WORD (abfd, src->p_vaddr); 367 dst->p_paddr = H_GET_WORD (abfd, src->p_paddr); 368 } 369 dst->p_filesz = H_GET_WORD (abfd, src->p_filesz); 370 dst->p_memsz = H_GET_WORD (abfd, src->p_memsz); 371 dst->p_align = H_GET_WORD (abfd, src->p_align); 372 } 373 374 void 375 elf_swap_phdr_out (bfd *abfd, 376 const Elf_Internal_Phdr *src, 377 Elf_External_Phdr *dst) 378 { 379 const struct elf_backend_data *bed; 380 bfd_vma p_paddr; 381 382 bed = get_elf_backend_data (abfd); 383 p_paddr = bed->want_p_paddr_set_to_zero ? 0 : src->p_paddr; 384 385 /* note that all elements of dst are *arrays of unsigned char* already... */ 386 H_PUT_32 (abfd, src->p_type, dst->p_type); 387 H_PUT_WORD (abfd, src->p_offset, dst->p_offset); 388 H_PUT_WORD (abfd, src->p_vaddr, dst->p_vaddr); 389 H_PUT_WORD (abfd, p_paddr, dst->p_paddr); 390 H_PUT_WORD (abfd, src->p_filesz, dst->p_filesz); 391 H_PUT_WORD (abfd, src->p_memsz, dst->p_memsz); 392 H_PUT_32 (abfd, src->p_flags, dst->p_flags); 393 H_PUT_WORD (abfd, src->p_align, dst->p_align); 394 } 395 396 /* Translate an ELF reloc from external format to internal format. */ 397 void 398 elf_swap_reloc_in (bfd *abfd, 399 const bfd_byte *s, 400 Elf_Internal_Rela *dst) 401 { 402 const Elf_External_Rel *src = (const Elf_External_Rel *) s; 403 dst->r_offset = H_GET_WORD (abfd, src->r_offset); 404 dst->r_info = H_GET_WORD (abfd, src->r_info); 405 dst->r_addend = 0; 406 } 407 408 void 409 elf_swap_reloca_in (bfd *abfd, 410 const bfd_byte *s, 411 Elf_Internal_Rela *dst) 412 { 413 const Elf_External_Rela *src = (const Elf_External_Rela *) s; 414 dst->r_offset = H_GET_WORD (abfd, src->r_offset); 415 dst->r_info = H_GET_WORD (abfd, src->r_info); 416 dst->r_addend = H_GET_SIGNED_WORD (abfd, src->r_addend); 417 } 418 419 /* Translate an ELF reloc from internal format to external format. */ 420 void 421 elf_swap_reloc_out (bfd *abfd, 422 const Elf_Internal_Rela *src, 423 bfd_byte *d) 424 { 425 Elf_External_Rel *dst = (Elf_External_Rel *) d; 426 H_PUT_WORD (abfd, src->r_offset, dst->r_offset); 427 H_PUT_WORD (abfd, src->r_info, dst->r_info); 428 } 429 430 void 431 elf_swap_reloca_out (bfd *abfd, 432 const Elf_Internal_Rela *src, 433 bfd_byte *d) 434 { 435 Elf_External_Rela *dst = (Elf_External_Rela *) d; 436 H_PUT_WORD (abfd, src->r_offset, dst->r_offset); 437 H_PUT_WORD (abfd, src->r_info, dst->r_info); 438 H_PUT_SIGNED_WORD (abfd, src->r_addend, dst->r_addend); 439 } 440 441 void 442 elf_swap_dyn_in (bfd *abfd, 443 const void *p, 444 Elf_Internal_Dyn *dst) 445 { 446 const Elf_External_Dyn *src = (const Elf_External_Dyn *) p; 447 448 dst->d_tag = H_GET_WORD (abfd, src->d_tag); 449 dst->d_un.d_val = H_GET_WORD (abfd, src->d_un.d_val); 450 } 451 452 void 453 elf_swap_dyn_out (bfd *abfd, 454 const Elf_Internal_Dyn *src, 455 void *p) 456 { 457 Elf_External_Dyn *dst = (Elf_External_Dyn *) p; 458 459 H_PUT_WORD (abfd, src->d_tag, dst->d_tag); 460 H_PUT_WORD (abfd, src->d_un.d_val, dst->d_un.d_val); 461 } 462 463 /* ELF .o/exec file reading */ 464 465 /* Begin processing a given object. 466 467 First we validate the file by reading in the ELF header and checking 468 the magic number. */ 469 470 static inline bfd_boolean 471 elf_file_p (Elf_External_Ehdr *x_ehdrp) 472 { 473 return ((x_ehdrp->e_ident[EI_MAG0] == ELFMAG0) 474 && (x_ehdrp->e_ident[EI_MAG1] == ELFMAG1) 475 && (x_ehdrp->e_ident[EI_MAG2] == ELFMAG2) 476 && (x_ehdrp->e_ident[EI_MAG3] == ELFMAG3)); 477 } 478 479 /* Check to see if the file associated with ABFD matches the target vector 480 that ABFD points to. 481 482 Note that we may be called several times with the same ABFD, but different 483 target vectors, most of which will not match. We have to avoid leaving 484 any side effects in ABFD, or any data it points to (like tdata), if the 485 file does not match the target vector. */ 486 487 const bfd_target * 488 elf_object_p (bfd *abfd) 489 { 490 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */ 491 Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form */ 492 Elf_External_Shdr x_shdr; /* Section header table entry, external form */ 493 Elf_Internal_Shdr i_shdr; 494 Elf_Internal_Shdr *i_shdrp; /* Section header table, internal form */ 495 unsigned int shindex; 496 const struct elf_backend_data *ebd; 497 asection *s; 498 bfd_size_type amt; 499 const bfd_target *target; 500 501 /* Read in the ELF header in external format. */ 502 503 if (bfd_bread (&x_ehdr, sizeof (x_ehdr), abfd) != sizeof (x_ehdr)) 504 { 505 if (bfd_get_error () != bfd_error_system_call) 506 goto got_wrong_format_error; 507 else 508 goto got_no_match; 509 } 510 511 /* Now check to see if we have a valid ELF file, and one that BFD can 512 make use of. The magic number must match, the address size ('class') 513 and byte-swapping must match our XVEC entry, and it must have a 514 section header table (FIXME: See comments re sections at top of this 515 file). */ 516 517 if (! elf_file_p (&x_ehdr) 518 || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT 519 || x_ehdr.e_ident[EI_CLASS] != ELFCLASS) 520 goto got_wrong_format_error; 521 522 /* Check that file's byte order matches xvec's */ 523 switch (x_ehdr.e_ident[EI_DATA]) 524 { 525 case ELFDATA2MSB: /* Big-endian */ 526 if (! bfd_header_big_endian (abfd)) 527 goto got_wrong_format_error; 528 break; 529 case ELFDATA2LSB: /* Little-endian */ 530 if (! bfd_header_little_endian (abfd)) 531 goto got_wrong_format_error; 532 break; 533 case ELFDATANONE: /* No data encoding specified */ 534 default: /* Unknown data encoding specified */ 535 goto got_wrong_format_error; 536 } 537 538 target = abfd->xvec; 539 540 /* Allocate an instance of the elf_obj_tdata structure and hook it up to 541 the tdata pointer in the bfd. */ 542 543 if (! (*target->_bfd_set_format[bfd_object]) (abfd)) 544 goto got_no_match; 545 546 /* Now that we know the byte order, swap in the rest of the header */ 547 i_ehdrp = elf_elfheader (abfd); 548 elf_swap_ehdr_in (abfd, &x_ehdr, i_ehdrp); 549 #if DEBUG & 1 550 elf_debug_file (i_ehdrp); 551 #endif 552 553 /* Reject ET_CORE (header indicates core file, not object file) */ 554 if (i_ehdrp->e_type == ET_CORE) 555 goto got_wrong_format_error; 556 557 /* If this is a relocatable file and there is no section header 558 table, then we're hosed. */ 559 if (i_ehdrp->e_shoff == 0 && i_ehdrp->e_type == ET_REL) 560 goto got_wrong_format_error; 561 562 /* As a simple sanity check, verify that what BFD thinks is the 563 size of each section header table entry actually matches the size 564 recorded in the file, but only if there are any sections. */ 565 if (i_ehdrp->e_shentsize != sizeof (x_shdr) && i_ehdrp->e_shnum != 0) 566 goto got_wrong_format_error; 567 568 /* Further sanity check. */ 569 if (i_ehdrp->e_shoff == 0 && i_ehdrp->e_shnum != 0) 570 goto got_wrong_format_error; 571 572 ebd = get_elf_backend_data (abfd); 573 if (ebd->s->arch_size != ARCH_SIZE) 574 goto got_wrong_format_error; 575 576 /* Check that the ELF e_machine field matches what this particular 577 BFD format expects. */ 578 if (ebd->elf_machine_code != i_ehdrp->e_machine 579 && (ebd->elf_machine_alt1 == 0 580 || i_ehdrp->e_machine != ebd->elf_machine_alt1) 581 && (ebd->elf_machine_alt2 == 0 582 || i_ehdrp->e_machine != ebd->elf_machine_alt2) 583 && ebd->elf_machine_code != EM_NONE) 584 goto got_wrong_format_error; 585 586 if (i_ehdrp->e_type == ET_EXEC) 587 abfd->flags |= EXEC_P; 588 else if (i_ehdrp->e_type == ET_DYN) 589 abfd->flags |= DYNAMIC; 590 591 if (i_ehdrp->e_phnum > 0) 592 abfd->flags |= D_PAGED; 593 594 if (! bfd_default_set_arch_mach (abfd, ebd->arch, 0)) 595 { 596 /* It's OK if this fails for the generic target. */ 597 if (ebd->elf_machine_code != EM_NONE) 598 goto got_no_match; 599 } 600 601 if (ebd->elf_machine_code != EM_NONE 602 && i_ehdrp->e_ident[EI_OSABI] != ebd->elf_osabi 603 && ebd->elf_osabi != ELFOSABI_NONE) 604 goto got_wrong_format_error; 605 606 if (i_ehdrp->e_shoff != 0) 607 { 608 file_ptr where = (file_ptr) i_ehdrp->e_shoff; 609 610 /* Seek to the section header table in the file. */ 611 if (bfd_seek (abfd, where, SEEK_SET) != 0) 612 goto got_no_match; 613 614 /* Read the first section header at index 0, and convert to internal 615 form. */ 616 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr)) 617 goto got_no_match; 618 elf_swap_shdr_in (abfd, &x_shdr, &i_shdr); 619 620 /* If the section count is zero, the actual count is in the first 621 section header. */ 622 if (i_ehdrp->e_shnum == SHN_UNDEF) 623 { 624 i_ehdrp->e_shnum = i_shdr.sh_size; 625 if (i_ehdrp->e_shnum >= SHN_LORESERVE 626 || i_ehdrp->e_shnum != i_shdr.sh_size 627 || i_ehdrp->e_shnum == 0) 628 goto got_wrong_format_error; 629 } 630 631 /* And similarly for the string table index. */ 632 if (i_ehdrp->e_shstrndx == (SHN_XINDEX & 0xffff)) 633 { 634 i_ehdrp->e_shstrndx = i_shdr.sh_link; 635 if (i_ehdrp->e_shstrndx != i_shdr.sh_link) 636 goto got_wrong_format_error; 637 } 638 639 /* And program headers. */ 640 if (i_ehdrp->e_phnum == PN_XNUM && i_shdr.sh_info != 0) 641 { 642 i_ehdrp->e_phnum = i_shdr.sh_info; 643 if (i_ehdrp->e_phnum != i_shdr.sh_info) 644 goto got_wrong_format_error; 645 } 646 647 /* Sanity check that we can read all of the section headers. 648 It ought to be good enough to just read the last one. */ 649 if (i_ehdrp->e_shnum != 1) 650 { 651 /* Check that we don't have a totally silly number of sections. */ 652 if (i_ehdrp->e_shnum > (unsigned int) -1 / sizeof (x_shdr) 653 || i_ehdrp->e_shnum > (unsigned int) -1 / sizeof (i_shdr)) 654 goto got_wrong_format_error; 655 656 where += (i_ehdrp->e_shnum - 1) * sizeof (x_shdr); 657 if ((bfd_size_type) where <= i_ehdrp->e_shoff) 658 goto got_wrong_format_error; 659 660 if (bfd_seek (abfd, where, SEEK_SET) != 0) 661 goto got_no_match; 662 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr)) 663 goto got_no_match; 664 665 /* Back to where we were. */ 666 where = i_ehdrp->e_shoff + sizeof (x_shdr); 667 if (bfd_seek (abfd, where, SEEK_SET) != 0) 668 goto got_no_match; 669 } 670 } 671 672 /* Allocate space for a copy of the section header table in 673 internal form. */ 674 if (i_ehdrp->e_shnum != 0) 675 { 676 Elf_Internal_Shdr *shdrp; 677 unsigned int num_sec; 678 679 #ifndef BFD64 680 if (i_ehdrp->e_shnum > ((bfd_size_type) -1) / sizeof (*i_shdrp)) 681 goto got_wrong_format_error; 682 #endif 683 amt = sizeof (*i_shdrp) * i_ehdrp->e_shnum; 684 i_shdrp = (Elf_Internal_Shdr *) bfd_alloc (abfd, amt); 685 if (!i_shdrp) 686 goto got_no_match; 687 num_sec = i_ehdrp->e_shnum; 688 elf_numsections (abfd) = num_sec; 689 amt = sizeof (i_shdrp) * num_sec; 690 elf_elfsections (abfd) = (Elf_Internal_Shdr **) bfd_alloc (abfd, amt); 691 if (!elf_elfsections (abfd)) 692 goto got_no_match; 693 694 memcpy (i_shdrp, &i_shdr, sizeof (*i_shdrp)); 695 for (shdrp = i_shdrp, shindex = 0; shindex < num_sec; shindex++) 696 elf_elfsections (abfd)[shindex] = shdrp++; 697 698 /* Read in the rest of the section header table and convert it 699 to internal form. */ 700 for (shindex = 1; shindex < i_ehdrp->e_shnum; shindex++) 701 { 702 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr)) 703 goto got_no_match; 704 elf_swap_shdr_in (abfd, &x_shdr, i_shdrp + shindex); 705 706 /* Sanity check sh_link and sh_info. */ 707 if (i_shdrp[shindex].sh_link >= num_sec) 708 { 709 /* PR 10478: Accept Solaris binaries with a sh_link 710 field set to SHN_BEFORE or SHN_AFTER. */ 711 switch (ebd->elf_machine_code) 712 { 713 case EM_386: 714 case EM_IAMCU: 715 case EM_X86_64: 716 case EM_OLD_SPARCV9: 717 case EM_SPARC32PLUS: 718 case EM_SPARCV9: 719 case EM_SPARC: 720 if (i_shdrp[shindex].sh_link == (SHN_LORESERVE & 0xffff) /* SHN_BEFORE */ 721 || i_shdrp[shindex].sh_link == ((SHN_LORESERVE + 1) & 0xffff) /* SHN_AFTER */) 722 break; 723 /* Otherwise fall through. */ 724 default: 725 goto got_wrong_format_error; 726 } 727 } 728 729 if (((i_shdrp[shindex].sh_flags & SHF_INFO_LINK) 730 || i_shdrp[shindex].sh_type == SHT_RELA 731 || i_shdrp[shindex].sh_type == SHT_REL) 732 && i_shdrp[shindex].sh_info >= num_sec) 733 goto got_wrong_format_error; 734 735 /* If the section is loaded, but not page aligned, clear 736 D_PAGED. */ 737 if (i_shdrp[shindex].sh_size != 0 738 && (i_shdrp[shindex].sh_flags & SHF_ALLOC) != 0 739 && i_shdrp[shindex].sh_type != SHT_NOBITS 740 && (((i_shdrp[shindex].sh_addr - i_shdrp[shindex].sh_offset) 741 % ebd->minpagesize) 742 != 0)) 743 abfd->flags &= ~D_PAGED; 744 } 745 } 746 747 /* A further sanity check. */ 748 if (i_ehdrp->e_shnum != 0) 749 { 750 if (i_ehdrp->e_shstrndx >= elf_numsections (abfd)) 751 { 752 /* PR 2257: 753 We used to just goto got_wrong_format_error here 754 but there are binaries in existance for which this test 755 will prevent the binutils from working with them at all. 756 So we are kind, and reset the string index value to 0 757 so that at least some processing can be done. */ 758 i_ehdrp->e_shstrndx = SHN_UNDEF; 759 _bfd_error_handler 760 (_("warning: %B has a corrupt string table index - ignoring"), 761 abfd); 762 } 763 } 764 else if (i_ehdrp->e_shstrndx != SHN_UNDEF) 765 goto got_wrong_format_error; 766 767 /* Read in the program headers. */ 768 if (i_ehdrp->e_phnum == 0) 769 elf_tdata (abfd)->phdr = NULL; 770 else 771 { 772 Elf_Internal_Phdr *i_phdr; 773 unsigned int i; 774 775 #ifndef BFD64 776 if (i_ehdrp->e_phnum > ((bfd_size_type) -1) / sizeof (*i_phdr)) 777 goto got_wrong_format_error; 778 #endif 779 amt = i_ehdrp->e_phnum * sizeof (*i_phdr); 780 elf_tdata (abfd)->phdr = (Elf_Internal_Phdr *) bfd_alloc (abfd, amt); 781 if (elf_tdata (abfd)->phdr == NULL) 782 goto got_no_match; 783 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_phoff, SEEK_SET) != 0) 784 goto got_no_match; 785 i_phdr = elf_tdata (abfd)->phdr; 786 for (i = 0; i < i_ehdrp->e_phnum; i++, i_phdr++) 787 { 788 Elf_External_Phdr x_phdr; 789 790 if (bfd_bread (&x_phdr, sizeof x_phdr, abfd) != sizeof x_phdr) 791 goto got_no_match; 792 elf_swap_phdr_in (abfd, &x_phdr, i_phdr); 793 } 794 } 795 796 if (i_ehdrp->e_shstrndx != 0 && i_ehdrp->e_shoff != 0) 797 { 798 unsigned int num_sec; 799 800 /* Once all of the section headers have been read and converted, we 801 can start processing them. Note that the first section header is 802 a dummy placeholder entry, so we ignore it. */ 803 num_sec = elf_numsections (abfd); 804 for (shindex = 1; shindex < num_sec; shindex++) 805 if (!bfd_section_from_shdr (abfd, shindex)) 806 goto got_no_match; 807 808 /* Set up ELF sections for SHF_GROUP and SHF_LINK_ORDER. */ 809 if (! _bfd_elf_setup_sections (abfd)) 810 goto got_wrong_format_error; 811 } 812 813 /* Let the backend double check the format and override global 814 information. */ 815 if (ebd->elf_backend_object_p) 816 { 817 if (! (*ebd->elf_backend_object_p) (abfd)) 818 goto got_wrong_format_error; 819 } 820 821 /* Remember the entry point specified in the ELF file header. */ 822 bfd_set_start_address (abfd, i_ehdrp->e_entry); 823 824 /* If we have created any reloc sections that are associated with 825 debugging sections, mark the reloc sections as debugging as well. */ 826 for (s = abfd->sections; s != NULL; s = s->next) 827 { 828 if ((elf_section_data (s)->this_hdr.sh_type == SHT_REL 829 || elf_section_data (s)->this_hdr.sh_type == SHT_RELA) 830 && elf_section_data (s)->this_hdr.sh_info > 0) 831 { 832 unsigned long targ_index; 833 asection *targ_sec; 834 835 targ_index = elf_section_data (s)->this_hdr.sh_info; 836 targ_sec = bfd_section_from_elf_index (abfd, targ_index); 837 if (targ_sec != NULL 838 && (targ_sec->flags & SEC_DEBUGGING) != 0) 839 s->flags |= SEC_DEBUGGING; 840 } 841 } 842 return target; 843 844 got_wrong_format_error: 845 bfd_set_error (bfd_error_wrong_format); 846 847 got_no_match: 848 return NULL; 849 } 850 851 /* ELF .o/exec file writing */ 852 853 /* Write out the relocs. */ 854 855 void 856 elf_write_relocs (bfd *abfd, asection *sec, void *data) 857 { 858 bfd_boolean *failedp = (bfd_boolean *) data; 859 Elf_Internal_Shdr *rela_hdr; 860 bfd_vma addr_offset; 861 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *); 862 size_t extsize; 863 bfd_byte *dst_rela; 864 unsigned int idx; 865 asymbol *last_sym; 866 int last_sym_idx; 867 868 /* If we have already failed, don't do anything. */ 869 if (*failedp) 870 return; 871 872 if ((sec->flags & SEC_RELOC) == 0) 873 return; 874 875 /* The linker backend writes the relocs out itself, and sets the 876 reloc_count field to zero to inhibit writing them here. Also, 877 sometimes the SEC_RELOC flag gets set even when there aren't any 878 relocs. */ 879 if (sec->reloc_count == 0) 880 return; 881 882 /* If we have opened an existing file for update, reloc_count may be 883 set even though we are not linking. In that case we have nothing 884 to do. */ 885 if (sec->orelocation == NULL) 886 return; 887 888 rela_hdr = elf_section_data (sec)->rela.hdr; 889 if (rela_hdr == NULL) 890 rela_hdr = elf_section_data (sec)->rel.hdr; 891 892 rela_hdr->sh_size = rela_hdr->sh_entsize * sec->reloc_count; 893 rela_hdr->contents = (unsigned char *) bfd_alloc (abfd, rela_hdr->sh_size); 894 if (rela_hdr->contents == NULL) 895 { 896 *failedp = TRUE; 897 return; 898 } 899 900 /* Figure out whether the relocations are RELA or REL relocations. */ 901 if (rela_hdr->sh_type == SHT_RELA) 902 { 903 swap_out = elf_swap_reloca_out; 904 extsize = sizeof (Elf_External_Rela); 905 } 906 else if (rela_hdr->sh_type == SHT_REL) 907 { 908 swap_out = elf_swap_reloc_out; 909 extsize = sizeof (Elf_External_Rel); 910 } 911 else 912 /* Every relocation section should be either an SHT_RELA or an 913 SHT_REL section. */ 914 abort (); 915 916 /* The address of an ELF reloc is section relative for an object 917 file, and absolute for an executable file or shared library. 918 The address of a BFD reloc is always section relative. */ 919 addr_offset = 0; 920 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0) 921 addr_offset = sec->vma; 922 923 /* orelocation has the data, reloc_count has the count... */ 924 last_sym = 0; 925 last_sym_idx = 0; 926 dst_rela = rela_hdr->contents; 927 928 for (idx = 0; idx < sec->reloc_count; idx++, dst_rela += extsize) 929 { 930 Elf_Internal_Rela src_rela; 931 arelent *ptr; 932 asymbol *sym; 933 int n; 934 935 ptr = sec->orelocation[idx]; 936 sym = *ptr->sym_ptr_ptr; 937 if (sym == last_sym) 938 n = last_sym_idx; 939 else if (bfd_is_abs_section (sym->section) && sym->value == 0) 940 n = STN_UNDEF; 941 else 942 { 943 last_sym = sym; 944 n = _bfd_elf_symbol_from_bfd_symbol (abfd, &sym); 945 if (n < 0) 946 { 947 *failedp = TRUE; 948 return; 949 } 950 last_sym_idx = n; 951 } 952 953 if ((*ptr->sym_ptr_ptr)->the_bfd != NULL 954 && (*ptr->sym_ptr_ptr)->the_bfd->xvec != abfd->xvec 955 && ! _bfd_elf_validate_reloc (abfd, ptr)) 956 { 957 *failedp = TRUE; 958 return; 959 } 960 961 src_rela.r_offset = ptr->address + addr_offset; 962 src_rela.r_info = ELF_R_INFO (n, ptr->howto->type); 963 src_rela.r_addend = ptr->addend; 964 (*swap_out) (abfd, &src_rela, dst_rela); 965 } 966 } 967 968 /* Write out the program headers. */ 969 970 int 971 elf_write_out_phdrs (bfd *abfd, 972 const Elf_Internal_Phdr *phdr, 973 unsigned int count) 974 { 975 while (count--) 976 { 977 Elf_External_Phdr extphdr; 978 979 elf_swap_phdr_out (abfd, phdr, &extphdr); 980 if (bfd_bwrite (&extphdr, sizeof (Elf_External_Phdr), abfd) 981 != sizeof (Elf_External_Phdr)) 982 return -1; 983 phdr++; 984 } 985 return 0; 986 } 987 988 /* Write out the section headers and the ELF file header. */ 989 990 bfd_boolean 991 elf_write_shdrs_and_ehdr (bfd *abfd) 992 { 993 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */ 994 Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form */ 995 Elf_External_Shdr *x_shdrp; /* Section header table, external form */ 996 Elf_Internal_Shdr **i_shdrp; /* Section header table, internal form */ 997 unsigned int count; 998 bfd_size_type amt; 999 1000 i_ehdrp = elf_elfheader (abfd); 1001 i_shdrp = elf_elfsections (abfd); 1002 1003 /* swap the header before spitting it out... */ 1004 1005 #if DEBUG & 1 1006 elf_debug_file (i_ehdrp); 1007 #endif 1008 elf_swap_ehdr_out (abfd, i_ehdrp, &x_ehdr); 1009 amt = sizeof (x_ehdr); 1010 if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0 1011 || bfd_bwrite (&x_ehdr, amt, abfd) != amt) 1012 return FALSE; 1013 1014 /* Some fields in the first section header handle overflow of ehdr 1015 fields. */ 1016 if (i_ehdrp->e_phnum >= PN_XNUM) 1017 i_shdrp[0]->sh_info = i_ehdrp->e_phnum; 1018 if (i_ehdrp->e_shnum >= (SHN_LORESERVE & 0xffff)) 1019 i_shdrp[0]->sh_size = i_ehdrp->e_shnum; 1020 if (i_ehdrp->e_shstrndx >= (SHN_LORESERVE & 0xffff)) 1021 i_shdrp[0]->sh_link = i_ehdrp->e_shstrndx; 1022 1023 /* at this point we've concocted all the ELF sections... */ 1024 amt = i_ehdrp->e_shnum; 1025 amt *= sizeof (*x_shdrp); 1026 x_shdrp = (Elf_External_Shdr *) bfd_alloc (abfd, amt); 1027 if (!x_shdrp) 1028 return FALSE; 1029 1030 for (count = 0; count < i_ehdrp->e_shnum; i_shdrp++, count++) 1031 { 1032 #if DEBUG & 2 1033 elf_debug_section (count, *i_shdrp); 1034 #endif 1035 elf_swap_shdr_out (abfd, *i_shdrp, x_shdrp + count); 1036 } 1037 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_shoff, SEEK_SET) != 0 1038 || bfd_bwrite (x_shdrp, amt, abfd) != amt) 1039 return FALSE; 1040 1041 /* need to dump the string table too... */ 1042 1043 return TRUE; 1044 } 1045 1046 bfd_boolean 1047 elf_checksum_contents (bfd *abfd, 1048 void (*process) (const void *, size_t, void *), 1049 void *arg) 1050 { 1051 Elf_Internal_Ehdr *i_ehdrp = elf_elfheader (abfd); 1052 Elf_Internal_Shdr **i_shdrp = elf_elfsections (abfd); 1053 Elf_Internal_Phdr *i_phdrp = elf_tdata (abfd)->phdr; 1054 unsigned int count, num; 1055 1056 { 1057 Elf_External_Ehdr x_ehdr; 1058 Elf_Internal_Ehdr i_ehdr; 1059 1060 i_ehdr = *i_ehdrp; 1061 i_ehdr.e_phoff = i_ehdr.e_shoff = 0; 1062 elf_swap_ehdr_out (abfd, &i_ehdr, &x_ehdr); 1063 (*process) (&x_ehdr, sizeof x_ehdr, arg); 1064 } 1065 1066 num = i_ehdrp->e_phnum; 1067 for (count = 0; count < num; count++) 1068 { 1069 Elf_External_Phdr x_phdr; 1070 elf_swap_phdr_out (abfd, &i_phdrp[count], &x_phdr); 1071 (*process) (&x_phdr, sizeof x_phdr, arg); 1072 } 1073 1074 num = elf_numsections (abfd); 1075 for (count = 0; count < num; count++) 1076 { 1077 Elf_Internal_Shdr i_shdr; 1078 Elf_External_Shdr x_shdr; 1079 bfd_byte *contents, *free_contents; 1080 1081 i_shdr = *i_shdrp[count]; 1082 i_shdr.sh_offset = 0; 1083 1084 elf_swap_shdr_out (abfd, &i_shdr, &x_shdr); 1085 (*process) (&x_shdr, sizeof x_shdr, arg); 1086 1087 /* Process the section's contents, if it has some. 1088 PR ld/12451: Read them in if necessary. */ 1089 if (i_shdr.sh_type == SHT_NOBITS) 1090 continue; 1091 free_contents = NULL; 1092 contents = i_shdr.contents; 1093 if (contents == NULL) 1094 { 1095 asection *sec; 1096 1097 sec = bfd_section_from_elf_index (abfd, count); 1098 if (sec != NULL) 1099 { 1100 contents = sec->contents; 1101 if (contents == NULL) 1102 { 1103 /* Force rereading from file. */ 1104 sec->flags &= ~SEC_IN_MEMORY; 1105 if (!bfd_malloc_and_get_section (abfd, sec, &free_contents)) 1106 continue; 1107 contents = free_contents; 1108 } 1109 } 1110 } 1111 if (contents != NULL) 1112 { 1113 (*process) (contents, i_shdr.sh_size, arg); 1114 if (free_contents != NULL) 1115 free (free_contents); 1116 } 1117 } 1118 1119 return TRUE; 1120 } 1121 1122 long 1123 elf_slurp_symbol_table (bfd *abfd, asymbol **symptrs, bfd_boolean dynamic) 1124 { 1125 Elf_Internal_Shdr *hdr; 1126 Elf_Internal_Shdr *verhdr; 1127 unsigned long symcount; /* Number of external ELF symbols */ 1128 elf_symbol_type *sym; /* Pointer to current bfd symbol */ 1129 elf_symbol_type *symbase; /* Buffer for generated bfd symbols */ 1130 Elf_Internal_Sym *isym; 1131 Elf_Internal_Sym *isymend; 1132 Elf_Internal_Sym *isymbuf = NULL; 1133 Elf_External_Versym *xver; 1134 Elf_External_Versym *xverbuf = NULL; 1135 const struct elf_backend_data *ebd; 1136 bfd_size_type amt; 1137 1138 /* Read each raw ELF symbol, converting from external ELF form to 1139 internal ELF form, and then using the information to create a 1140 canonical bfd symbol table entry. 1141 1142 Note that we allocate the initial bfd canonical symbol buffer 1143 based on a one-to-one mapping of the ELF symbols to canonical 1144 symbols. We actually use all the ELF symbols, so there will be no 1145 space left over at the end. When we have all the symbols, we 1146 build the caller's pointer vector. */ 1147 1148 if (! dynamic) 1149 { 1150 hdr = &elf_tdata (abfd)->symtab_hdr; 1151 verhdr = NULL; 1152 } 1153 else 1154 { 1155 hdr = &elf_tdata (abfd)->dynsymtab_hdr; 1156 if (elf_dynversym (abfd) == 0) 1157 verhdr = NULL; 1158 else 1159 verhdr = &elf_tdata (abfd)->dynversym_hdr; 1160 if ((elf_dynverdef (abfd) != 0 1161 && elf_tdata (abfd)->verdef == NULL) 1162 || (elf_dynverref (abfd) != 0 1163 && elf_tdata (abfd)->verref == NULL)) 1164 { 1165 if (!_bfd_elf_slurp_version_tables (abfd, FALSE)) 1166 return -1; 1167 } 1168 } 1169 1170 ebd = get_elf_backend_data (abfd); 1171 symcount = hdr->sh_size / sizeof (Elf_External_Sym); 1172 if (symcount == 0) 1173 sym = symbase = NULL; 1174 else 1175 { 1176 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, symcount, 0, 1177 NULL, NULL, NULL); 1178 if (isymbuf == NULL) 1179 return -1; 1180 1181 amt = symcount; 1182 amt *= sizeof (elf_symbol_type); 1183 symbase = (elf_symbol_type *) bfd_zalloc (abfd, amt); 1184 if (symbase == (elf_symbol_type *) NULL) 1185 goto error_return; 1186 1187 /* Read the raw ELF version symbol information. */ 1188 if (verhdr != NULL 1189 && verhdr->sh_size / sizeof (Elf_External_Versym) != symcount) 1190 { 1191 _bfd_error_handler 1192 /* xgettext:c-format */ 1193 (_("%B: version count (%ld) does not match symbol count (%ld)"), 1194 abfd, 1195 (long) (verhdr->sh_size / sizeof (Elf_External_Versym)), 1196 symcount); 1197 1198 /* Slurp in the symbols without the version information, 1199 since that is more helpful than just quitting. */ 1200 verhdr = NULL; 1201 } 1202 1203 if (verhdr != NULL) 1204 { 1205 if (bfd_seek (abfd, verhdr->sh_offset, SEEK_SET) != 0) 1206 goto error_return; 1207 1208 xverbuf = (Elf_External_Versym *) bfd_malloc (verhdr->sh_size); 1209 if (xverbuf == NULL && verhdr->sh_size != 0) 1210 goto error_return; 1211 1212 if (bfd_bread (xverbuf, verhdr->sh_size, abfd) != verhdr->sh_size) 1213 goto error_return; 1214 } 1215 1216 /* Skip first symbol, which is a null dummy. */ 1217 xver = xverbuf; 1218 if (xver != NULL) 1219 ++xver; 1220 isymend = isymbuf + symcount; 1221 for (isym = isymbuf + 1, sym = symbase; isym < isymend; isym++, sym++) 1222 { 1223 memcpy (&sym->internal_elf_sym, isym, sizeof (Elf_Internal_Sym)); 1224 1225 sym->symbol.the_bfd = abfd; 1226 sym->symbol.name = bfd_elf_sym_name (abfd, hdr, isym, NULL); 1227 sym->symbol.value = isym->st_value; 1228 1229 if (isym->st_shndx == SHN_UNDEF) 1230 { 1231 sym->symbol.section = bfd_und_section_ptr; 1232 } 1233 else if (isym->st_shndx == SHN_ABS) 1234 { 1235 sym->symbol.section = bfd_abs_section_ptr; 1236 } 1237 else if (isym->st_shndx == SHN_COMMON) 1238 { 1239 sym->symbol.section = bfd_com_section_ptr; 1240 if ((abfd->flags & BFD_PLUGIN) != 0) 1241 { 1242 asection *xc = bfd_get_section_by_name (abfd, "COMMON"); 1243 1244 if (xc == NULL) 1245 { 1246 flagword flags = (SEC_ALLOC | SEC_IS_COMMON | SEC_KEEP 1247 | SEC_EXCLUDE); 1248 xc = bfd_make_section_with_flags (abfd, "COMMON", flags); 1249 if (xc == NULL) 1250 goto error_return; 1251 } 1252 sym->symbol.section = xc; 1253 } 1254 /* Elf puts the alignment into the `value' field, and 1255 the size into the `size' field. BFD wants to see the 1256 size in the value field, and doesn't care (at the 1257 moment) about the alignment. */ 1258 sym->symbol.value = isym->st_size; 1259 } 1260 else 1261 { 1262 sym->symbol.section 1263 = bfd_section_from_elf_index (abfd, isym->st_shndx); 1264 if (sym->symbol.section == NULL) 1265 { 1266 /* This symbol is in a section for which we did not 1267 create a BFD section. Just use bfd_abs_section, 1268 although it is wrong. FIXME. */ 1269 sym->symbol.section = bfd_abs_section_ptr; 1270 } 1271 } 1272 1273 /* If this is a relocatable file, then the symbol value is 1274 already section relative. */ 1275 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0) 1276 sym->symbol.value -= sym->symbol.section->vma; 1277 1278 switch (ELF_ST_BIND (isym->st_info)) 1279 { 1280 case STB_LOCAL: 1281 sym->symbol.flags |= BSF_LOCAL; 1282 break; 1283 case STB_GLOBAL: 1284 if (isym->st_shndx != SHN_UNDEF && isym->st_shndx != SHN_COMMON) 1285 sym->symbol.flags |= BSF_GLOBAL; 1286 break; 1287 case STB_WEAK: 1288 sym->symbol.flags |= BSF_WEAK; 1289 break; 1290 case STB_GNU_UNIQUE: 1291 sym->symbol.flags |= BSF_GNU_UNIQUE; 1292 break; 1293 } 1294 1295 switch (ELF_ST_TYPE (isym->st_info)) 1296 { 1297 case STT_SECTION: 1298 sym->symbol.flags |= BSF_SECTION_SYM | BSF_DEBUGGING; 1299 break; 1300 case STT_FILE: 1301 sym->symbol.flags |= BSF_FILE | BSF_DEBUGGING; 1302 break; 1303 case STT_FUNC: 1304 sym->symbol.flags |= BSF_FUNCTION; 1305 break; 1306 case STT_COMMON: 1307 /* FIXME: Do we have to put the size field into the value field 1308 as we do with symbols in SHN_COMMON sections (see above) ? */ 1309 sym->symbol.flags |= BSF_ELF_COMMON; 1310 /* Fall through. */ 1311 case STT_OBJECT: 1312 sym->symbol.flags |= BSF_OBJECT; 1313 break; 1314 case STT_TLS: 1315 sym->symbol.flags |= BSF_THREAD_LOCAL; 1316 break; 1317 case STT_RELC: 1318 sym->symbol.flags |= BSF_RELC; 1319 break; 1320 case STT_SRELC: 1321 sym->symbol.flags |= BSF_SRELC; 1322 break; 1323 case STT_GNU_IFUNC: 1324 sym->symbol.flags |= BSF_GNU_INDIRECT_FUNCTION; 1325 break; 1326 } 1327 1328 if (dynamic) 1329 sym->symbol.flags |= BSF_DYNAMIC; 1330 1331 if (xver != NULL) 1332 { 1333 Elf_Internal_Versym iversym; 1334 1335 _bfd_elf_swap_versym_in (abfd, xver, &iversym); 1336 sym->version = iversym.vs_vers; 1337 xver++; 1338 } 1339 1340 /* Do some backend-specific processing on this symbol. */ 1341 if (ebd->elf_backend_symbol_processing) 1342 (*ebd->elf_backend_symbol_processing) (abfd, &sym->symbol); 1343 } 1344 } 1345 1346 /* Do some backend-specific processing on this symbol table. */ 1347 if (ebd->elf_backend_symbol_table_processing) 1348 (*ebd->elf_backend_symbol_table_processing) (abfd, symbase, symcount); 1349 1350 /* We rely on the zalloc to clear out the final symbol entry. */ 1351 1352 symcount = sym - symbase; 1353 1354 /* Fill in the user's symbol pointer vector if needed. */ 1355 if (symptrs) 1356 { 1357 long l = symcount; 1358 1359 sym = symbase; 1360 while (l-- > 0) 1361 { 1362 *symptrs++ = &sym->symbol; 1363 sym++; 1364 } 1365 *symptrs = 0; /* Final null pointer */ 1366 } 1367 1368 if (xverbuf != NULL) 1369 free (xverbuf); 1370 if (isymbuf != NULL && hdr->contents != (unsigned char *) isymbuf) 1371 free (isymbuf); 1372 return symcount; 1373 1374 error_return: 1375 if (xverbuf != NULL) 1376 free (xverbuf); 1377 if (isymbuf != NULL && hdr->contents != (unsigned char *) isymbuf) 1378 free (isymbuf); 1379 return -1; 1380 } 1381 1382 /* Read relocations for ASECT from REL_HDR. There are RELOC_COUNT of 1383 them. */ 1384 1385 static bfd_boolean 1386 elf_slurp_reloc_table_from_section (bfd *abfd, 1387 asection *asect, 1388 Elf_Internal_Shdr *rel_hdr, 1389 bfd_size_type reloc_count, 1390 arelent *relents, 1391 asymbol **symbols, 1392 bfd_boolean dynamic) 1393 { 1394 const struct elf_backend_data * const ebd = get_elf_backend_data (abfd); 1395 void *allocated = NULL; 1396 bfd_byte *native_relocs; 1397 arelent *relent; 1398 unsigned int i; 1399 int entsize; 1400 unsigned int symcount; 1401 1402 allocated = bfd_malloc (rel_hdr->sh_size); 1403 if (allocated == NULL) 1404 goto error_return; 1405 1406 if (bfd_seek (abfd, rel_hdr->sh_offset, SEEK_SET) != 0 1407 || (bfd_bread (allocated, rel_hdr->sh_size, abfd) 1408 != rel_hdr->sh_size)) 1409 goto error_return; 1410 1411 native_relocs = (bfd_byte *) allocated; 1412 1413 entsize = rel_hdr->sh_entsize; 1414 BFD_ASSERT (entsize == sizeof (Elf_External_Rel) 1415 || entsize == sizeof (Elf_External_Rela)); 1416 1417 if (dynamic) 1418 symcount = bfd_get_dynamic_symcount (abfd); 1419 else 1420 symcount = bfd_get_symcount (abfd); 1421 1422 for (i = 0, relent = relents; 1423 i < reloc_count; 1424 i++, relent++, native_relocs += entsize) 1425 { 1426 Elf_Internal_Rela rela; 1427 1428 if (entsize == sizeof (Elf_External_Rela)) 1429 elf_swap_reloca_in (abfd, native_relocs, &rela); 1430 else 1431 elf_swap_reloc_in (abfd, native_relocs, &rela); 1432 1433 /* The address of an ELF reloc is section relative for an object 1434 file, and absolute for an executable file or shared library. 1435 The address of a normal BFD reloc is always section relative, 1436 and the address of a dynamic reloc is absolute.. */ 1437 if ((abfd->flags & (EXEC_P | DYNAMIC)) == 0 || dynamic) 1438 relent->address = rela.r_offset; 1439 else 1440 relent->address = rela.r_offset - asect->vma; 1441 1442 if (ELF_R_SYM (rela.r_info) == STN_UNDEF) 1443 relent->sym_ptr_ptr = bfd_abs_section_ptr->symbol_ptr_ptr; 1444 else if (ELF_R_SYM (rela.r_info) > symcount) 1445 { 1446 _bfd_error_handler 1447 /* xgettext:c-format */ 1448 (_("%B(%A): relocation %d has invalid symbol index %ld"), 1449 abfd, asect, i, ELF_R_SYM (rela.r_info)); 1450 relent->sym_ptr_ptr = bfd_abs_section_ptr->symbol_ptr_ptr; 1451 } 1452 else 1453 { 1454 asymbol **ps; 1455 1456 ps = symbols + ELF_R_SYM (rela.r_info) - 1; 1457 1458 relent->sym_ptr_ptr = ps; 1459 } 1460 1461 relent->addend = rela.r_addend; 1462 1463 if ((entsize == sizeof (Elf_External_Rela) 1464 && ebd->elf_info_to_howto != NULL) 1465 || ebd->elf_info_to_howto_rel == NULL) 1466 (*ebd->elf_info_to_howto) (abfd, relent, &rela); 1467 else 1468 (*ebd->elf_info_to_howto_rel) (abfd, relent, &rela); 1469 } 1470 1471 if (allocated != NULL) 1472 free (allocated); 1473 1474 return TRUE; 1475 1476 error_return: 1477 if (allocated != NULL) 1478 free (allocated); 1479 return FALSE; 1480 } 1481 1482 /* Read in and swap the external relocs. */ 1483 1484 bfd_boolean 1485 elf_slurp_reloc_table (bfd *abfd, 1486 asection *asect, 1487 asymbol **symbols, 1488 bfd_boolean dynamic) 1489 { 1490 struct bfd_elf_section_data * const d = elf_section_data (asect); 1491 Elf_Internal_Shdr *rel_hdr; 1492 Elf_Internal_Shdr *rel_hdr2; 1493 bfd_size_type reloc_count; 1494 bfd_size_type reloc_count2; 1495 arelent *relents; 1496 bfd_size_type amt; 1497 1498 if (asect->relocation != NULL) 1499 return TRUE; 1500 1501 if (! dynamic) 1502 { 1503 if ((asect->flags & SEC_RELOC) == 0 1504 || asect->reloc_count == 0) 1505 return TRUE; 1506 1507 rel_hdr = d->rel.hdr; 1508 reloc_count = rel_hdr ? NUM_SHDR_ENTRIES (rel_hdr) : 0; 1509 rel_hdr2 = d->rela.hdr; 1510 reloc_count2 = rel_hdr2 ? NUM_SHDR_ENTRIES (rel_hdr2) : 0; 1511 1512 /* PR 17512: file: 0b4f81b7. */ 1513 if (asect->reloc_count != reloc_count + reloc_count2) 1514 return FALSE; 1515 BFD_ASSERT ((rel_hdr && asect->rel_filepos == rel_hdr->sh_offset) 1516 || (rel_hdr2 && asect->rel_filepos == rel_hdr2->sh_offset)); 1517 1518 } 1519 else 1520 { 1521 /* Note that ASECT->RELOC_COUNT tends not to be accurate in this 1522 case because relocations against this section may use the 1523 dynamic symbol table, and in that case bfd_section_from_shdr 1524 in elf.c does not update the RELOC_COUNT. */ 1525 if (asect->size == 0) 1526 return TRUE; 1527 1528 rel_hdr = &d->this_hdr; 1529 reloc_count = NUM_SHDR_ENTRIES (rel_hdr); 1530 rel_hdr2 = NULL; 1531 reloc_count2 = 0; 1532 } 1533 1534 amt = (reloc_count + reloc_count2) * sizeof (arelent); 1535 relents = (arelent *) bfd_alloc (abfd, amt); 1536 if (relents == NULL) 1537 return FALSE; 1538 1539 if (rel_hdr 1540 && !elf_slurp_reloc_table_from_section (abfd, asect, 1541 rel_hdr, reloc_count, 1542 relents, 1543 symbols, dynamic)) 1544 return FALSE; 1545 1546 if (rel_hdr2 1547 && !elf_slurp_reloc_table_from_section (abfd, asect, 1548 rel_hdr2, reloc_count2, 1549 relents + reloc_count, 1550 symbols, dynamic)) 1551 return FALSE; 1552 1553 asect->relocation = relents; 1554 return TRUE; 1555 } 1556 1557 #if DEBUG & 2 1558 static void 1559 elf_debug_section (int num, Elf_Internal_Shdr *hdr) 1560 { 1561 fprintf (stderr, "\nSection#%d '%s' 0x%.8lx\n", num, 1562 hdr->bfd_section != NULL ? hdr->bfd_section->name : "", 1563 (long) hdr); 1564 fprintf (stderr, 1565 "sh_name = %ld\tsh_type = %ld\tsh_flags = %ld\n", 1566 (long) hdr->sh_name, 1567 (long) hdr->sh_type, 1568 (long) hdr->sh_flags); 1569 fprintf (stderr, 1570 "sh_addr = %ld\tsh_offset = %ld\tsh_size = %ld\n", 1571 (long) hdr->sh_addr, 1572 (long) hdr->sh_offset, 1573 (long) hdr->sh_size); 1574 fprintf (stderr, 1575 "sh_link = %ld\tsh_info = %ld\tsh_addralign = %ld\n", 1576 (long) hdr->sh_link, 1577 (long) hdr->sh_info, 1578 (long) hdr->sh_addralign); 1579 fprintf (stderr, "sh_entsize = %ld\n", 1580 (long) hdr->sh_entsize); 1581 fflush (stderr); 1582 } 1583 #endif 1584 1585 #if DEBUG & 1 1586 static void 1587 elf_debug_file (Elf_Internal_Ehdr *ehdrp) 1588 { 1589 fprintf (stderr, "e_entry = 0x%.8lx\n", (long) ehdrp->e_entry); 1590 fprintf (stderr, "e_phoff = %ld\n", (long) ehdrp->e_phoff); 1591 fprintf (stderr, "e_phnum = %ld\n", (long) ehdrp->e_phnum); 1592 fprintf (stderr, "e_phentsize = %ld\n", (long) ehdrp->e_phentsize); 1593 fprintf (stderr, "e_shoff = %ld\n", (long) ehdrp->e_shoff); 1594 fprintf (stderr, "e_shnum = %ld\n", (long) ehdrp->e_shnum); 1595 fprintf (stderr, "e_shentsize = %ld\n", (long) ehdrp->e_shentsize); 1596 } 1597 #endif 1598 1599 /* Create a new BFD as if by bfd_openr. Rather than opening a file, 1600 reconstruct an ELF file by reading the segments out of remote 1601 memory based on the ELF file header at EHDR_VMA and the ELF program 1602 headers it points to. If non-zero, SIZE is the known extent of the 1603 object. If not null, *LOADBASEP is filled in with the difference 1604 between the VMAs from which the segments were read, and the VMAs 1605 the file headers (and hence BFD's idea of each section's VMA) put 1606 them at. 1607 1608 The function TARGET_READ_MEMORY is called to copy LEN bytes from 1609 the remote memory at target address VMA into the local buffer at 1610 MYADDR; it should return zero on success or an `errno' code on 1611 failure. TEMPL must be a BFD for a target with the word size and 1612 byte order found in the remote memory. */ 1613 1614 bfd * 1615 NAME(_bfd_elf,bfd_from_remote_memory) 1616 (bfd *templ, 1617 bfd_vma ehdr_vma, 1618 bfd_size_type size, 1619 bfd_vma *loadbasep, 1620 int (*target_read_memory) (bfd_vma, bfd_byte *, bfd_size_type)) 1621 { 1622 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */ 1623 Elf_Internal_Ehdr i_ehdr; /* Elf file header, internal form */ 1624 Elf_External_Phdr *x_phdrs; 1625 Elf_Internal_Phdr *i_phdrs, *last_phdr, *first_phdr; 1626 bfd *nbfd; 1627 struct bfd_in_memory *bim; 1628 bfd_byte *contents; 1629 int err; 1630 unsigned int i; 1631 bfd_vma high_offset; 1632 bfd_vma shdr_end; 1633 bfd_vma loadbase; 1634 1635 /* Read in the ELF header in external format. */ 1636 err = target_read_memory (ehdr_vma, (bfd_byte *) &x_ehdr, sizeof x_ehdr); 1637 if (err) 1638 { 1639 bfd_set_error (bfd_error_system_call); 1640 errno = err; 1641 return NULL; 1642 } 1643 1644 /* Now check to see if we have a valid ELF file, and one that BFD can 1645 make use of. The magic number must match, the address size ('class') 1646 and byte-swapping must match our XVEC entry. */ 1647 1648 if (! elf_file_p (&x_ehdr) 1649 || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT 1650 || x_ehdr.e_ident[EI_CLASS] != ELFCLASS) 1651 { 1652 bfd_set_error (bfd_error_wrong_format); 1653 return NULL; 1654 } 1655 1656 /* Check that file's byte order matches xvec's */ 1657 switch (x_ehdr.e_ident[EI_DATA]) 1658 { 1659 case ELFDATA2MSB: /* Big-endian */ 1660 if (! bfd_header_big_endian (templ)) 1661 { 1662 bfd_set_error (bfd_error_wrong_format); 1663 return NULL; 1664 } 1665 break; 1666 case ELFDATA2LSB: /* Little-endian */ 1667 if (! bfd_header_little_endian (templ)) 1668 { 1669 bfd_set_error (bfd_error_wrong_format); 1670 return NULL; 1671 } 1672 break; 1673 case ELFDATANONE: /* No data encoding specified */ 1674 default: /* Unknown data encoding specified */ 1675 bfd_set_error (bfd_error_wrong_format); 1676 return NULL; 1677 } 1678 1679 elf_swap_ehdr_in (templ, &x_ehdr, &i_ehdr); 1680 1681 /* The file header tells where to find the program headers. 1682 These are what we use to actually choose what to read. */ 1683 1684 if (i_ehdr.e_phentsize != sizeof (Elf_External_Phdr) || i_ehdr.e_phnum == 0) 1685 { 1686 bfd_set_error (bfd_error_wrong_format); 1687 return NULL; 1688 } 1689 1690 x_phdrs = (Elf_External_Phdr *) 1691 bfd_malloc (i_ehdr.e_phnum * (sizeof *x_phdrs + sizeof *i_phdrs)); 1692 if (x_phdrs == NULL) 1693 return NULL; 1694 err = target_read_memory (ehdr_vma + i_ehdr.e_phoff, (bfd_byte *) x_phdrs, 1695 i_ehdr.e_phnum * sizeof x_phdrs[0]); 1696 if (err) 1697 { 1698 free (x_phdrs); 1699 bfd_set_error (bfd_error_system_call); 1700 errno = err; 1701 return NULL; 1702 } 1703 i_phdrs = (Elf_Internal_Phdr *) &x_phdrs[i_ehdr.e_phnum]; 1704 1705 high_offset = 0; 1706 loadbase = 0; 1707 first_phdr = NULL; 1708 last_phdr = NULL; 1709 for (i = 0; i < i_ehdr.e_phnum; ++i) 1710 { 1711 elf_swap_phdr_in (templ, &x_phdrs[i], &i_phdrs[i]); 1712 if (i_phdrs[i].p_type == PT_LOAD) 1713 { 1714 bfd_vma segment_end = i_phdrs[i].p_offset + i_phdrs[i].p_filesz; 1715 1716 if (segment_end > high_offset) 1717 { 1718 high_offset = segment_end; 1719 last_phdr = &i_phdrs[i]; 1720 } 1721 1722 /* If this program header covers offset zero, where the file 1723 header sits, then we can figure out the loadbase. */ 1724 if (first_phdr == NULL) 1725 { 1726 bfd_vma p_offset = i_phdrs[i].p_offset; 1727 bfd_vma p_vaddr = i_phdrs[i].p_vaddr; 1728 1729 if (i_phdrs[i].p_align > 1) 1730 { 1731 p_offset &= -i_phdrs[i].p_align; 1732 p_vaddr &= -i_phdrs[i].p_align; 1733 } 1734 if (p_offset == 0) 1735 { 1736 loadbase = ehdr_vma - p_vaddr; 1737 first_phdr = &i_phdrs[i]; 1738 } 1739 } 1740 } 1741 } 1742 if (high_offset == 0) 1743 { 1744 /* There were no PT_LOAD segments, so we don't have anything to read. */ 1745 free (x_phdrs); 1746 bfd_set_error (bfd_error_wrong_format); 1747 return NULL; 1748 } 1749 1750 shdr_end = 0; 1751 if (i_ehdr.e_shoff != 0 && i_ehdr.e_shnum != 0 && i_ehdr.e_shentsize != 0) 1752 { 1753 shdr_end = i_ehdr.e_shoff + i_ehdr.e_shnum * i_ehdr.e_shentsize; 1754 1755 if (last_phdr->p_filesz != last_phdr->p_memsz) 1756 { 1757 /* If the last PT_LOAD header has a bss area then ld.so will 1758 have cleared anything past p_filesz, zapping the section 1759 headers. */ 1760 } 1761 else if (size >= shdr_end) 1762 high_offset = size; 1763 else 1764 { 1765 bfd_vma page_size = get_elf_backend_data (templ)->minpagesize; 1766 bfd_vma segment_end = last_phdr->p_offset + last_phdr->p_filesz; 1767 1768 /* Assume we loaded full pages, allowing us to sometimes see 1769 section headers. */ 1770 if (page_size > 1 && shdr_end > segment_end) 1771 { 1772 bfd_vma page_end = (segment_end + page_size - 1) & -page_size; 1773 1774 if (page_end >= shdr_end) 1775 /* Whee, section headers covered. */ 1776 high_offset = shdr_end; 1777 } 1778 } 1779 } 1780 1781 /* Now we know the size of the whole image we want read in. */ 1782 contents = (bfd_byte *) bfd_zmalloc (high_offset); 1783 if (contents == NULL) 1784 { 1785 free (x_phdrs); 1786 return NULL; 1787 } 1788 1789 for (i = 0; i < i_ehdr.e_phnum; ++i) 1790 if (i_phdrs[i].p_type == PT_LOAD) 1791 { 1792 bfd_vma start = i_phdrs[i].p_offset; 1793 bfd_vma end = start + i_phdrs[i].p_filesz; 1794 bfd_vma vaddr = i_phdrs[i].p_vaddr; 1795 1796 /* Extend the beginning of the first pt_load to cover file 1797 header and program headers, if we proved earlier that its 1798 aligned offset is 0. */ 1799 if (first_phdr == &i_phdrs[i]) 1800 { 1801 vaddr -= start; 1802 start = 0; 1803 } 1804 /* Extend the end of the last pt_load to cover section headers. */ 1805 if (last_phdr == &i_phdrs[i]) 1806 end = high_offset; 1807 err = target_read_memory (loadbase + vaddr, 1808 contents + start, end - start); 1809 if (err) 1810 { 1811 free (x_phdrs); 1812 free (contents); 1813 bfd_set_error (bfd_error_system_call); 1814 errno = err; 1815 return NULL; 1816 } 1817 } 1818 free (x_phdrs); 1819 1820 /* If the segments visible in memory didn't include the section headers, 1821 then clear them from the file header. */ 1822 if (high_offset < shdr_end) 1823 { 1824 memset (&x_ehdr.e_shoff, 0, sizeof x_ehdr.e_shoff); 1825 memset (&x_ehdr.e_shnum, 0, sizeof x_ehdr.e_shnum); 1826 memset (&x_ehdr.e_shstrndx, 0, sizeof x_ehdr.e_shstrndx); 1827 } 1828 1829 /* This will normally have been in the first PT_LOAD segment. But it 1830 conceivably could be missing, and we might have just changed it. */ 1831 memcpy (contents, &x_ehdr, sizeof x_ehdr); 1832 1833 /* Now we have a memory image of the ELF file contents. Make a BFD. */ 1834 bim = (struct bfd_in_memory *) bfd_malloc (sizeof (struct bfd_in_memory)); 1835 if (bim == NULL) 1836 { 1837 free (contents); 1838 return NULL; 1839 } 1840 nbfd = _bfd_new_bfd (); 1841 if (nbfd == NULL) 1842 { 1843 free (bim); 1844 free (contents); 1845 return NULL; 1846 } 1847 nbfd->filename = xstrdup ("<in-memory>"); 1848 nbfd->xvec = templ->xvec; 1849 bim->size = high_offset; 1850 bim->buffer = contents; 1851 nbfd->iostream = bim; 1852 nbfd->flags = BFD_IN_MEMORY; 1853 nbfd->iovec = &_bfd_memory_iovec; 1854 nbfd->origin = 0; 1855 nbfd->direction = read_direction; 1856 nbfd->mtime = time (NULL); 1857 nbfd->mtime_set = TRUE; 1858 1859 if (loadbasep) 1860 *loadbasep = loadbase; 1861 return nbfd; 1862 } 1863 1864 /* Function for ELF_R_INFO. */ 1865 1866 bfd_vma 1867 NAME(elf,r_info) (bfd_vma sym, bfd_vma type) 1868 { 1869 return ELF_R_INFO (sym, type); 1870 } 1871 1872 /* Function for ELF_R_SYM. */ 1873 1874 bfd_vma 1875 NAME(elf,r_sym) (bfd_vma r_info) 1876 { 1877 return ELF_R_SYM (r_info); 1878 } 1879 1880 #include "elfcore.h" 1881 1882 /* Size-dependent data and functions. */ 1883 const struct elf_size_info NAME(_bfd_elf,size_info) = { 1884 sizeof (Elf_External_Ehdr), 1885 sizeof (Elf_External_Phdr), 1886 sizeof (Elf_External_Shdr), 1887 sizeof (Elf_External_Rel), 1888 sizeof (Elf_External_Rela), 1889 sizeof (Elf_External_Sym), 1890 sizeof (Elf_External_Dyn), 1891 sizeof (Elf_External_Note), 1892 4, 1893 1, 1894 ARCH_SIZE, LOG_FILE_ALIGN, 1895 ELFCLASS, EV_CURRENT, 1896 elf_write_out_phdrs, 1897 elf_write_shdrs_and_ehdr, 1898 elf_checksum_contents, 1899 elf_write_relocs, 1900 elf_swap_symbol_in, 1901 elf_swap_symbol_out, 1902 elf_slurp_reloc_table, 1903 elf_slurp_symbol_table, 1904 elf_swap_dyn_in, 1905 elf_swap_dyn_out, 1906 elf_swap_reloc_in, 1907 elf_swap_reloc_out, 1908 elf_swap_reloca_in, 1909 elf_swap_reloca_out 1910 }; 1911