1 /* ELF executable support for BFD. 2 Copyright (C) 1991-2019 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 /* PR 23657. Check for invalid section size, in sections with contents. 318 Note - we do not set an error value here because the contents 319 of this particular section might not be needed by the consumer. */ 320 if (dst->sh_type != SHT_NOBITS 321 && dst->sh_size > bfd_get_file_size (abfd)) 322 _bfd_error_handler 323 (_("warning: %pB has a corrupt section with a size (%" BFD_VMA_FMT "x) larger than the file size"), 324 abfd, dst->sh_size); 325 dst->sh_link = H_GET_32 (abfd, src->sh_link); 326 dst->sh_info = H_GET_32 (abfd, src->sh_info); 327 dst->sh_addralign = H_GET_WORD (abfd, src->sh_addralign); 328 dst->sh_entsize = H_GET_WORD (abfd, src->sh_entsize); 329 dst->bfd_section = NULL; 330 dst->contents = NULL; 331 } 332 333 /* Translate an ELF section header table entry in internal format into an 334 ELF section header table entry in external format. */ 335 336 static void 337 elf_swap_shdr_out (bfd *abfd, 338 const Elf_Internal_Shdr *src, 339 Elf_External_Shdr *dst) 340 { 341 /* note that all elements of dst are *arrays of unsigned char* already... */ 342 H_PUT_32 (abfd, src->sh_name, dst->sh_name); 343 H_PUT_32 (abfd, src->sh_type, dst->sh_type); 344 H_PUT_WORD (abfd, src->sh_flags, dst->sh_flags); 345 H_PUT_WORD (abfd, src->sh_addr, dst->sh_addr); 346 H_PUT_WORD (abfd, src->sh_offset, dst->sh_offset); 347 H_PUT_WORD (abfd, src->sh_size, dst->sh_size); 348 H_PUT_32 (abfd, src->sh_link, dst->sh_link); 349 H_PUT_32 (abfd, src->sh_info, dst->sh_info); 350 H_PUT_WORD (abfd, src->sh_addralign, dst->sh_addralign); 351 H_PUT_WORD (abfd, src->sh_entsize, dst->sh_entsize); 352 } 353 354 /* Translate an ELF program header table entry in external format into an 355 ELF program header table entry in internal format. */ 356 357 void 358 elf_swap_phdr_in (bfd *abfd, 359 const Elf_External_Phdr *src, 360 Elf_Internal_Phdr *dst) 361 { 362 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma; 363 364 dst->p_type = H_GET_32 (abfd, src->p_type); 365 dst->p_flags = H_GET_32 (abfd, src->p_flags); 366 dst->p_offset = H_GET_WORD (abfd, src->p_offset); 367 if (signed_vma) 368 { 369 dst->p_vaddr = H_GET_SIGNED_WORD (abfd, src->p_vaddr); 370 dst->p_paddr = H_GET_SIGNED_WORD (abfd, src->p_paddr); 371 } 372 else 373 { 374 dst->p_vaddr = H_GET_WORD (abfd, src->p_vaddr); 375 dst->p_paddr = H_GET_WORD (abfd, src->p_paddr); 376 } 377 dst->p_filesz = H_GET_WORD (abfd, src->p_filesz); 378 dst->p_memsz = H_GET_WORD (abfd, src->p_memsz); 379 dst->p_align = H_GET_WORD (abfd, src->p_align); 380 } 381 382 void 383 elf_swap_phdr_out (bfd *abfd, 384 const Elf_Internal_Phdr *src, 385 Elf_External_Phdr *dst) 386 { 387 const struct elf_backend_data *bed; 388 bfd_vma p_paddr; 389 390 bed = get_elf_backend_data (abfd); 391 p_paddr = bed->want_p_paddr_set_to_zero ? 0 : src->p_paddr; 392 393 /* note that all elements of dst are *arrays of unsigned char* already... */ 394 H_PUT_32 (abfd, src->p_type, dst->p_type); 395 H_PUT_WORD (abfd, src->p_offset, dst->p_offset); 396 H_PUT_WORD (abfd, src->p_vaddr, dst->p_vaddr); 397 H_PUT_WORD (abfd, p_paddr, dst->p_paddr); 398 H_PUT_WORD (abfd, src->p_filesz, dst->p_filesz); 399 H_PUT_WORD (abfd, src->p_memsz, dst->p_memsz); 400 H_PUT_32 (abfd, src->p_flags, dst->p_flags); 401 H_PUT_WORD (abfd, src->p_align, dst->p_align); 402 } 403 404 /* Translate an ELF reloc from external format to internal format. */ 405 void 406 elf_swap_reloc_in (bfd *abfd, 407 const bfd_byte *s, 408 Elf_Internal_Rela *dst) 409 { 410 const Elf_External_Rel *src = (const Elf_External_Rel *) s; 411 dst->r_offset = H_GET_WORD (abfd, src->r_offset); 412 dst->r_info = H_GET_WORD (abfd, src->r_info); 413 dst->r_addend = 0; 414 } 415 416 void 417 elf_swap_reloca_in (bfd *abfd, 418 const bfd_byte *s, 419 Elf_Internal_Rela *dst) 420 { 421 const Elf_External_Rela *src = (const Elf_External_Rela *) s; 422 dst->r_offset = H_GET_WORD (abfd, src->r_offset); 423 dst->r_info = H_GET_WORD (abfd, src->r_info); 424 dst->r_addend = H_GET_SIGNED_WORD (abfd, src->r_addend); 425 } 426 427 /* Translate an ELF reloc from internal format to external format. */ 428 void 429 elf_swap_reloc_out (bfd *abfd, 430 const Elf_Internal_Rela *src, 431 bfd_byte *d) 432 { 433 Elf_External_Rel *dst = (Elf_External_Rel *) d; 434 H_PUT_WORD (abfd, src->r_offset, dst->r_offset); 435 H_PUT_WORD (abfd, src->r_info, dst->r_info); 436 } 437 438 void 439 elf_swap_reloca_out (bfd *abfd, 440 const Elf_Internal_Rela *src, 441 bfd_byte *d) 442 { 443 Elf_External_Rela *dst = (Elf_External_Rela *) d; 444 H_PUT_WORD (abfd, src->r_offset, dst->r_offset); 445 H_PUT_WORD (abfd, src->r_info, dst->r_info); 446 H_PUT_SIGNED_WORD (abfd, src->r_addend, dst->r_addend); 447 } 448 449 void 450 elf_swap_dyn_in (bfd *abfd, 451 const void *p, 452 Elf_Internal_Dyn *dst) 453 { 454 const Elf_External_Dyn *src = (const Elf_External_Dyn *) p; 455 456 dst->d_tag = H_GET_WORD (abfd, src->d_tag); 457 dst->d_un.d_val = H_GET_WORD (abfd, src->d_un.d_val); 458 } 459 460 void 461 elf_swap_dyn_out (bfd *abfd, 462 const Elf_Internal_Dyn *src, 463 void *p) 464 { 465 Elf_External_Dyn *dst = (Elf_External_Dyn *) p; 466 467 H_PUT_WORD (abfd, src->d_tag, dst->d_tag); 468 H_PUT_WORD (abfd, src->d_un.d_val, dst->d_un.d_val); 469 } 470 471 /* ELF .o/exec file reading */ 472 473 /* Begin processing a given object. 474 475 First we validate the file by reading in the ELF header and checking 476 the magic number. */ 477 478 static inline bfd_boolean 479 elf_file_p (Elf_External_Ehdr *x_ehdrp) 480 { 481 return ((x_ehdrp->e_ident[EI_MAG0] == ELFMAG0) 482 && (x_ehdrp->e_ident[EI_MAG1] == ELFMAG1) 483 && (x_ehdrp->e_ident[EI_MAG2] == ELFMAG2) 484 && (x_ehdrp->e_ident[EI_MAG3] == ELFMAG3)); 485 } 486 487 /* Check to see if the file associated with ABFD matches the target vector 488 that ABFD points to. 489 490 Note that we may be called several times with the same ABFD, but different 491 target vectors, most of which will not match. We have to avoid leaving 492 any side effects in ABFD, or any data it points to (like tdata), if the 493 file does not match the target vector. */ 494 495 const bfd_target * 496 elf_object_p (bfd *abfd) 497 { 498 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */ 499 Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form */ 500 Elf_External_Shdr x_shdr; /* Section header table entry, external form */ 501 Elf_Internal_Shdr i_shdr; 502 Elf_Internal_Shdr *i_shdrp; /* Section header table, internal form */ 503 unsigned int shindex; 504 const struct elf_backend_data *ebd; 505 asection *s; 506 bfd_size_type amt; 507 const bfd_target *target; 508 509 /* Read in the ELF header in external format. */ 510 511 if (bfd_bread (&x_ehdr, sizeof (x_ehdr), abfd) != sizeof (x_ehdr)) 512 { 513 if (bfd_get_error () != bfd_error_system_call) 514 goto got_wrong_format_error; 515 else 516 goto got_no_match; 517 } 518 519 /* Now check to see if we have a valid ELF file, and one that BFD can 520 make use of. The magic number must match, the address size ('class') 521 and byte-swapping must match our XVEC entry, and it must have a 522 section header table (FIXME: See comments re sections at top of this 523 file). */ 524 525 if (! elf_file_p (&x_ehdr) 526 || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT 527 || x_ehdr.e_ident[EI_CLASS] != ELFCLASS) 528 goto got_wrong_format_error; 529 530 /* Check that file's byte order matches xvec's */ 531 switch (x_ehdr.e_ident[EI_DATA]) 532 { 533 case ELFDATA2MSB: /* Big-endian */ 534 if (! bfd_header_big_endian (abfd)) 535 goto got_wrong_format_error; 536 break; 537 case ELFDATA2LSB: /* Little-endian */ 538 if (! bfd_header_little_endian (abfd)) 539 goto got_wrong_format_error; 540 break; 541 case ELFDATANONE: /* No data encoding specified */ 542 default: /* Unknown data encoding specified */ 543 goto got_wrong_format_error; 544 } 545 546 target = abfd->xvec; 547 548 /* Allocate an instance of the elf_obj_tdata structure and hook it up to 549 the tdata pointer in the bfd. */ 550 551 if (! (*target->_bfd_set_format[bfd_object]) (abfd)) 552 goto got_no_match; 553 554 /* Now that we know the byte order, swap in the rest of the header */ 555 i_ehdrp = elf_elfheader (abfd); 556 elf_swap_ehdr_in (abfd, &x_ehdr, i_ehdrp); 557 #if DEBUG & 1 558 elf_debug_file (i_ehdrp); 559 #endif 560 561 /* Reject ET_CORE (header indicates core file, not object file) */ 562 if (i_ehdrp->e_type == ET_CORE) 563 goto got_wrong_format_error; 564 565 /* If this is a relocatable file and there is no section header 566 table, then we're hosed. */ 567 if (i_ehdrp->e_shoff == 0 && i_ehdrp->e_type == ET_REL) 568 goto got_wrong_format_error; 569 570 /* As a simple sanity check, verify that what BFD thinks is the 571 size of each section header table entry actually matches the size 572 recorded in the file, but only if there are any sections. */ 573 if (i_ehdrp->e_shentsize != sizeof (x_shdr) && i_ehdrp->e_shnum != 0) 574 goto got_wrong_format_error; 575 576 /* Further sanity check. */ 577 if (i_ehdrp->e_shoff == 0 && i_ehdrp->e_shnum != 0) 578 goto got_wrong_format_error; 579 580 ebd = get_elf_backend_data (abfd); 581 if (ebd->s->arch_size != ARCH_SIZE) 582 goto got_wrong_format_error; 583 584 /* Check that the ELF e_machine field matches what this particular 585 BFD format expects. */ 586 if (ebd->elf_machine_code != i_ehdrp->e_machine 587 && (ebd->elf_machine_alt1 == 0 588 || i_ehdrp->e_machine != ebd->elf_machine_alt1) 589 && (ebd->elf_machine_alt2 == 0 590 || i_ehdrp->e_machine != ebd->elf_machine_alt2) 591 && ebd->elf_machine_code != EM_NONE) 592 goto got_wrong_format_error; 593 594 if (i_ehdrp->e_type == ET_EXEC) 595 abfd->flags |= EXEC_P; 596 else if (i_ehdrp->e_type == ET_DYN) 597 abfd->flags |= DYNAMIC; 598 599 if (i_ehdrp->e_phnum > 0) 600 abfd->flags |= D_PAGED; 601 602 if (! bfd_default_set_arch_mach (abfd, ebd->arch, 0)) 603 { 604 /* It's OK if this fails for the generic target. */ 605 if (ebd->elf_machine_code != EM_NONE) 606 goto got_no_match; 607 } 608 609 if (ebd->elf_machine_code != EM_NONE 610 && i_ehdrp->e_ident[EI_OSABI] != ebd->elf_osabi 611 && ebd->elf_osabi != ELFOSABI_NONE) 612 goto got_wrong_format_error; 613 614 if (i_ehdrp->e_shoff != 0) 615 { 616 file_ptr where = (file_ptr) i_ehdrp->e_shoff; 617 618 /* Seek to the section header table in the file. */ 619 if (bfd_seek (abfd, where, SEEK_SET) != 0) 620 goto got_no_match; 621 622 /* Read the first section header at index 0, and convert to internal 623 form. */ 624 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr)) 625 goto got_no_match; 626 elf_swap_shdr_in (abfd, &x_shdr, &i_shdr); 627 628 /* If the section count is zero, the actual count is in the first 629 section header. */ 630 if (i_ehdrp->e_shnum == SHN_UNDEF) 631 { 632 i_ehdrp->e_shnum = i_shdr.sh_size; 633 if (i_ehdrp->e_shnum >= SHN_LORESERVE 634 || i_ehdrp->e_shnum != i_shdr.sh_size 635 || i_ehdrp->e_shnum == 0) 636 goto got_wrong_format_error; 637 } 638 639 /* And similarly for the string table index. */ 640 if (i_ehdrp->e_shstrndx == (SHN_XINDEX & 0xffff)) 641 { 642 i_ehdrp->e_shstrndx = i_shdr.sh_link; 643 if (i_ehdrp->e_shstrndx != i_shdr.sh_link) 644 goto got_wrong_format_error; 645 } 646 647 /* And program headers. */ 648 if (i_ehdrp->e_phnum == PN_XNUM && i_shdr.sh_info != 0) 649 { 650 i_ehdrp->e_phnum = i_shdr.sh_info; 651 if (i_ehdrp->e_phnum != i_shdr.sh_info) 652 goto got_wrong_format_error; 653 } 654 655 /* Sanity check that we can read all of the section headers. 656 It ought to be good enough to just read the last one. */ 657 if (i_ehdrp->e_shnum != 1) 658 { 659 /* Check that we don't have a totally silly number of sections. */ 660 if (i_ehdrp->e_shnum > (unsigned int) -1 / sizeof (x_shdr) 661 || i_ehdrp->e_shnum > (unsigned int) -1 / sizeof (i_shdr)) 662 goto got_wrong_format_error; 663 664 where += (i_ehdrp->e_shnum - 1) * sizeof (x_shdr); 665 if ((bfd_size_type) where <= i_ehdrp->e_shoff) 666 goto got_wrong_format_error; 667 668 if (bfd_seek (abfd, where, SEEK_SET) != 0) 669 goto got_no_match; 670 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr)) 671 goto got_no_match; 672 673 /* Back to where we were. */ 674 where = i_ehdrp->e_shoff + sizeof (x_shdr); 675 if (bfd_seek (abfd, where, SEEK_SET) != 0) 676 goto got_no_match; 677 } 678 } 679 680 /* Allocate space for a copy of the section header table in 681 internal form. */ 682 if (i_ehdrp->e_shnum != 0) 683 { 684 Elf_Internal_Shdr *shdrp; 685 unsigned int num_sec; 686 687 #ifndef BFD64 688 if (i_ehdrp->e_shnum > ((bfd_size_type) -1) / sizeof (*i_shdrp)) 689 goto got_wrong_format_error; 690 #endif 691 amt = sizeof (*i_shdrp) * (bfd_size_type) i_ehdrp->e_shnum; 692 i_shdrp = (Elf_Internal_Shdr *) bfd_alloc (abfd, amt); 693 if (!i_shdrp) 694 goto got_no_match; 695 num_sec = i_ehdrp->e_shnum; 696 elf_numsections (abfd) = num_sec; 697 amt = sizeof (i_shdrp) * num_sec; 698 elf_elfsections (abfd) = (Elf_Internal_Shdr **) bfd_alloc (abfd, amt); 699 if (!elf_elfsections (abfd)) 700 goto got_no_match; 701 702 memcpy (i_shdrp, &i_shdr, sizeof (*i_shdrp)); 703 for (shdrp = i_shdrp, shindex = 0; shindex < num_sec; shindex++) 704 elf_elfsections (abfd)[shindex] = shdrp++; 705 706 /* Read in the rest of the section header table and convert it 707 to internal form. */ 708 for (shindex = 1; shindex < i_ehdrp->e_shnum; shindex++) 709 { 710 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr)) 711 goto got_no_match; 712 elf_swap_shdr_in (abfd, &x_shdr, i_shdrp + shindex); 713 714 /* Sanity check sh_link and sh_info. */ 715 if (i_shdrp[shindex].sh_link >= num_sec) 716 { 717 /* PR 10478: Accept Solaris binaries with a sh_link 718 field set to SHN_BEFORE or SHN_AFTER. */ 719 switch (ebd->elf_machine_code) 720 { 721 case EM_386: 722 case EM_IAMCU: 723 case EM_X86_64: 724 case EM_OLD_SPARCV9: 725 case EM_SPARC32PLUS: 726 case EM_SPARCV9: 727 case EM_SPARC: 728 if (i_shdrp[shindex].sh_link == (SHN_LORESERVE & 0xffff) /* SHN_BEFORE */ 729 || i_shdrp[shindex].sh_link == ((SHN_LORESERVE + 1) & 0xffff) /* SHN_AFTER */) 730 break; 731 /* Otherwise fall through. */ 732 default: 733 goto got_wrong_format_error; 734 } 735 } 736 737 if (((i_shdrp[shindex].sh_flags & SHF_INFO_LINK) 738 || i_shdrp[shindex].sh_type == SHT_RELA 739 || i_shdrp[shindex].sh_type == SHT_REL) 740 && i_shdrp[shindex].sh_info >= num_sec) 741 goto got_wrong_format_error; 742 743 /* If the section is loaded, but not page aligned, clear 744 D_PAGED. */ 745 if (i_shdrp[shindex].sh_size != 0 746 && (i_shdrp[shindex].sh_flags & SHF_ALLOC) != 0 747 && i_shdrp[shindex].sh_type != SHT_NOBITS 748 && (((i_shdrp[shindex].sh_addr - i_shdrp[shindex].sh_offset) 749 % ebd->minpagesize) 750 != 0)) 751 abfd->flags &= ~D_PAGED; 752 } 753 } 754 755 /* A further sanity check. */ 756 if (i_ehdrp->e_shnum != 0) 757 { 758 if (i_ehdrp->e_shstrndx >= elf_numsections (abfd)) 759 { 760 /* PR 2257: 761 We used to just goto got_wrong_format_error here 762 but there are binaries in existance for which this test 763 will prevent the binutils from working with them at all. 764 So we are kind, and reset the string index value to 0 765 so that at least some processing can be done. */ 766 i_ehdrp->e_shstrndx = SHN_UNDEF; 767 _bfd_error_handler 768 (_("warning: %pB has a corrupt string table index - ignoring"), 769 abfd); 770 } 771 } 772 else if (i_ehdrp->e_shstrndx != SHN_UNDEF) 773 goto got_wrong_format_error; 774 775 /* Read in the program headers. */ 776 if (i_ehdrp->e_phnum == 0) 777 elf_tdata (abfd)->phdr = NULL; 778 else 779 { 780 Elf_Internal_Phdr *i_phdr; 781 unsigned int i; 782 783 #ifndef BFD64 784 if (i_ehdrp->e_phnum > ((bfd_size_type) -1) / sizeof (*i_phdr)) 785 goto got_wrong_format_error; 786 #endif 787 /* Check for a corrupt input file with an impossibly large number 788 of program headers. */ 789 if (bfd_get_file_size (abfd) > 0 790 && i_ehdrp->e_phnum > bfd_get_file_size (abfd)) 791 goto got_no_match; 792 amt = (bfd_size_type) i_ehdrp->e_phnum * sizeof (*i_phdr); 793 elf_tdata (abfd)->phdr = (Elf_Internal_Phdr *) bfd_alloc (abfd, amt); 794 if (elf_tdata (abfd)->phdr == NULL) 795 goto got_no_match; 796 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_phoff, SEEK_SET) != 0) 797 goto got_no_match; 798 i_phdr = elf_tdata (abfd)->phdr; 799 for (i = 0; i < i_ehdrp->e_phnum; i++, i_phdr++) 800 { 801 Elf_External_Phdr x_phdr; 802 803 if (bfd_bread (&x_phdr, sizeof x_phdr, abfd) != sizeof x_phdr) 804 goto got_no_match; 805 elf_swap_phdr_in (abfd, &x_phdr, i_phdr); 806 } 807 } 808 809 if (i_ehdrp->e_shstrndx != 0 && i_ehdrp->e_shoff != 0) 810 { 811 unsigned int num_sec; 812 813 /* Once all of the section headers have been read and converted, we 814 can start processing them. Note that the first section header is 815 a dummy placeholder entry, so we ignore it. */ 816 num_sec = elf_numsections (abfd); 817 for (shindex = 1; shindex < num_sec; shindex++) 818 if (!bfd_section_from_shdr (abfd, shindex)) 819 goto got_no_match; 820 821 /* Set up ELF sections for SHF_GROUP and SHF_LINK_ORDER. */ 822 if (! _bfd_elf_setup_sections (abfd)) 823 goto got_wrong_format_error; 824 } 825 826 /* Let the backend double check the format and override global 827 information. */ 828 if (ebd->elf_backend_object_p) 829 { 830 if (! (*ebd->elf_backend_object_p) (abfd)) 831 goto got_wrong_format_error; 832 } 833 834 /* Remember the entry point specified in the ELF file header. */ 835 bfd_set_start_address (abfd, i_ehdrp->e_entry); 836 837 /* If we have created any reloc sections that are associated with 838 debugging sections, mark the reloc sections as debugging as well. */ 839 for (s = abfd->sections; s != NULL; s = s->next) 840 { 841 if ((elf_section_data (s)->this_hdr.sh_type == SHT_REL 842 || elf_section_data (s)->this_hdr.sh_type == SHT_RELA) 843 && elf_section_data (s)->this_hdr.sh_info > 0) 844 { 845 unsigned long targ_index; 846 asection *targ_sec; 847 848 targ_index = elf_section_data (s)->this_hdr.sh_info; 849 targ_sec = bfd_section_from_elf_index (abfd, targ_index); 850 if (targ_sec != NULL 851 && (targ_sec->flags & SEC_DEBUGGING) != 0) 852 s->flags |= SEC_DEBUGGING; 853 } 854 } 855 return target; 856 857 got_wrong_format_error: 858 bfd_set_error (bfd_error_wrong_format); 859 860 got_no_match: 861 return NULL; 862 } 863 864 /* ELF .o/exec file writing */ 865 866 /* Write out the relocs. */ 867 868 void 869 elf_write_relocs (bfd *abfd, asection *sec, void *data) 870 { 871 bfd_boolean *failedp = (bfd_boolean *) data; 872 Elf_Internal_Shdr *rela_hdr; 873 bfd_vma addr_offset; 874 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *); 875 size_t extsize; 876 bfd_byte *dst_rela; 877 unsigned int idx; 878 asymbol *last_sym; 879 int last_sym_idx; 880 881 /* If we have already failed, don't do anything. */ 882 if (*failedp) 883 return; 884 885 if ((sec->flags & SEC_RELOC) == 0) 886 return; 887 888 /* The linker backend writes the relocs out itself, and sets the 889 reloc_count field to zero to inhibit writing them here. Also, 890 sometimes the SEC_RELOC flag gets set even when there aren't any 891 relocs. */ 892 if (sec->reloc_count == 0) 893 return; 894 895 /* If we have opened an existing file for update, reloc_count may be 896 set even though we are not linking. In that case we have nothing 897 to do. */ 898 if (sec->orelocation == NULL) 899 return; 900 901 rela_hdr = elf_section_data (sec)->rela.hdr; 902 if (rela_hdr == NULL) 903 rela_hdr = elf_section_data (sec)->rel.hdr; 904 905 rela_hdr->sh_size = rela_hdr->sh_entsize * sec->reloc_count; 906 rela_hdr->contents = (unsigned char *) bfd_alloc (abfd, rela_hdr->sh_size); 907 if (rela_hdr->contents == NULL) 908 { 909 *failedp = TRUE; 910 return; 911 } 912 913 /* Figure out whether the relocations are RELA or REL relocations. */ 914 if (rela_hdr->sh_type == SHT_RELA) 915 { 916 swap_out = elf_swap_reloca_out; 917 extsize = sizeof (Elf_External_Rela); 918 } 919 else if (rela_hdr->sh_type == SHT_REL) 920 { 921 swap_out = elf_swap_reloc_out; 922 extsize = sizeof (Elf_External_Rel); 923 } 924 else 925 /* Every relocation section should be either an SHT_RELA or an 926 SHT_REL section. */ 927 abort (); 928 929 /* The address of an ELF reloc is section relative for an object 930 file, and absolute for an executable file or shared library. 931 The address of a BFD reloc is always section relative. */ 932 addr_offset = 0; 933 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0) 934 addr_offset = sec->vma; 935 936 /* orelocation has the data, reloc_count has the count... */ 937 last_sym = 0; 938 last_sym_idx = 0; 939 dst_rela = rela_hdr->contents; 940 941 for (idx = 0; idx < sec->reloc_count; idx++, dst_rela += extsize) 942 { 943 Elf_Internal_Rela src_rela; 944 arelent *ptr; 945 asymbol *sym; 946 int n; 947 948 ptr = sec->orelocation[idx]; 949 sym = *ptr->sym_ptr_ptr; 950 if (sym == last_sym) 951 n = last_sym_idx; 952 else if (bfd_is_abs_section (sym->section) && sym->value == 0) 953 n = STN_UNDEF; 954 else 955 { 956 last_sym = sym; 957 n = _bfd_elf_symbol_from_bfd_symbol (abfd, &sym); 958 if (n < 0) 959 { 960 *failedp = TRUE; 961 return; 962 } 963 last_sym_idx = n; 964 } 965 966 if ((*ptr->sym_ptr_ptr)->the_bfd != NULL 967 && (*ptr->sym_ptr_ptr)->the_bfd->xvec != abfd->xvec 968 && ! _bfd_elf_validate_reloc (abfd, ptr)) 969 { 970 *failedp = TRUE; 971 return; 972 } 973 974 if (ptr->howto == NULL) 975 { 976 *failedp = TRUE; 977 return; 978 } 979 980 src_rela.r_offset = ptr->address + addr_offset; 981 src_rela.r_info = ELF_R_INFO (n, ptr->howto->type); 982 src_rela.r_addend = ptr->addend; 983 (*swap_out) (abfd, &src_rela, dst_rela); 984 } 985 } 986 987 /* Write out the program headers. */ 988 989 int 990 elf_write_out_phdrs (bfd *abfd, 991 const Elf_Internal_Phdr *phdr, 992 unsigned int count) 993 { 994 while (count--) 995 { 996 Elf_External_Phdr extphdr; 997 998 elf_swap_phdr_out (abfd, phdr, &extphdr); 999 if (bfd_bwrite (&extphdr, sizeof (Elf_External_Phdr), abfd) 1000 != sizeof (Elf_External_Phdr)) 1001 return -1; 1002 phdr++; 1003 } 1004 return 0; 1005 } 1006 1007 /* Write out the section headers and the ELF file header. */ 1008 1009 bfd_boolean 1010 elf_write_shdrs_and_ehdr (bfd *abfd) 1011 { 1012 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */ 1013 Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form */ 1014 Elf_External_Shdr *x_shdrp; /* Section header table, external form */ 1015 Elf_Internal_Shdr **i_shdrp; /* Section header table, internal form */ 1016 unsigned int count; 1017 bfd_size_type amt; 1018 1019 i_ehdrp = elf_elfheader (abfd); 1020 i_shdrp = elf_elfsections (abfd); 1021 1022 /* swap the header before spitting it out... */ 1023 1024 #if DEBUG & 1 1025 elf_debug_file (i_ehdrp); 1026 #endif 1027 elf_swap_ehdr_out (abfd, i_ehdrp, &x_ehdr); 1028 amt = sizeof (x_ehdr); 1029 if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0 1030 || bfd_bwrite (&x_ehdr, amt, abfd) != amt) 1031 return FALSE; 1032 1033 /* Some fields in the first section header handle overflow of ehdr 1034 fields. */ 1035 if (i_ehdrp->e_phnum >= PN_XNUM) 1036 i_shdrp[0]->sh_info = i_ehdrp->e_phnum; 1037 if (i_ehdrp->e_shnum >= (SHN_LORESERVE & 0xffff)) 1038 i_shdrp[0]->sh_size = i_ehdrp->e_shnum; 1039 if (i_ehdrp->e_shstrndx >= (SHN_LORESERVE & 0xffff)) 1040 i_shdrp[0]->sh_link = i_ehdrp->e_shstrndx; 1041 1042 /* at this point we've concocted all the ELF sections... */ 1043 amt = i_ehdrp->e_shnum; 1044 amt *= sizeof (*x_shdrp); 1045 x_shdrp = (Elf_External_Shdr *) bfd_alloc (abfd, amt); 1046 if (!x_shdrp) 1047 return FALSE; 1048 1049 for (count = 0; count < i_ehdrp->e_shnum; i_shdrp++, count++) 1050 { 1051 #if DEBUG & 2 1052 elf_debug_section (count, *i_shdrp); 1053 #endif 1054 elf_swap_shdr_out (abfd, *i_shdrp, x_shdrp + count); 1055 } 1056 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_shoff, SEEK_SET) != 0 1057 || bfd_bwrite (x_shdrp, amt, abfd) != amt) 1058 return FALSE; 1059 1060 /* need to dump the string table too... */ 1061 1062 return TRUE; 1063 } 1064 1065 bfd_boolean 1066 elf_checksum_contents (bfd *abfd, 1067 void (*process) (const void *, size_t, void *), 1068 void *arg) 1069 { 1070 Elf_Internal_Ehdr *i_ehdrp = elf_elfheader (abfd); 1071 Elf_Internal_Shdr **i_shdrp = elf_elfsections (abfd); 1072 Elf_Internal_Phdr *i_phdrp = elf_tdata (abfd)->phdr; 1073 unsigned int count, num; 1074 1075 { 1076 Elf_External_Ehdr x_ehdr; 1077 Elf_Internal_Ehdr i_ehdr; 1078 1079 i_ehdr = *i_ehdrp; 1080 i_ehdr.e_phoff = i_ehdr.e_shoff = 0; 1081 elf_swap_ehdr_out (abfd, &i_ehdr, &x_ehdr); 1082 (*process) (&x_ehdr, sizeof x_ehdr, arg); 1083 } 1084 1085 num = i_ehdrp->e_phnum; 1086 for (count = 0; count < num; count++) 1087 { 1088 Elf_External_Phdr x_phdr; 1089 elf_swap_phdr_out (abfd, &i_phdrp[count], &x_phdr); 1090 (*process) (&x_phdr, sizeof x_phdr, arg); 1091 } 1092 1093 num = elf_numsections (abfd); 1094 for (count = 0; count < num; count++) 1095 { 1096 Elf_Internal_Shdr i_shdr; 1097 Elf_External_Shdr x_shdr; 1098 bfd_byte *contents, *free_contents; 1099 1100 i_shdr = *i_shdrp[count]; 1101 i_shdr.sh_offset = 0; 1102 1103 elf_swap_shdr_out (abfd, &i_shdr, &x_shdr); 1104 (*process) (&x_shdr, sizeof x_shdr, arg); 1105 1106 /* Process the section's contents, if it has some. 1107 PR ld/12451: Read them in if necessary. */ 1108 if (i_shdr.sh_type == SHT_NOBITS) 1109 continue; 1110 free_contents = NULL; 1111 contents = i_shdr.contents; 1112 if (contents == NULL) 1113 { 1114 asection *sec; 1115 1116 sec = bfd_section_from_elf_index (abfd, count); 1117 if (sec != NULL) 1118 { 1119 contents = sec->contents; 1120 if (contents == NULL) 1121 { 1122 /* Force rereading from file. */ 1123 sec->flags &= ~SEC_IN_MEMORY; 1124 if (!bfd_malloc_and_get_section (abfd, sec, &free_contents)) 1125 continue; 1126 contents = free_contents; 1127 } 1128 } 1129 } 1130 if (contents != NULL) 1131 { 1132 (*process) (contents, i_shdr.sh_size, arg); 1133 if (free_contents != NULL) 1134 free (free_contents); 1135 } 1136 } 1137 1138 return TRUE; 1139 } 1140 1141 long 1142 elf_slurp_symbol_table (bfd *abfd, asymbol **symptrs, bfd_boolean dynamic) 1143 { 1144 Elf_Internal_Shdr *hdr; 1145 Elf_Internal_Shdr *verhdr; 1146 unsigned long symcount; /* Number of external ELF symbols */ 1147 elf_symbol_type *sym; /* Pointer to current bfd symbol */ 1148 elf_symbol_type *symbase; /* Buffer for generated bfd symbols */ 1149 Elf_Internal_Sym *isym; 1150 Elf_Internal_Sym *isymend; 1151 Elf_Internal_Sym *isymbuf = NULL; 1152 Elf_External_Versym *xver; 1153 Elf_External_Versym *xverbuf = NULL; 1154 const struct elf_backend_data *ebd; 1155 bfd_size_type amt; 1156 1157 /* Read each raw ELF symbol, converting from external ELF form to 1158 internal ELF form, and then using the information to create a 1159 canonical bfd symbol table entry. 1160 1161 Note that we allocate the initial bfd canonical symbol buffer 1162 based on a one-to-one mapping of the ELF symbols to canonical 1163 symbols. We actually use all the ELF symbols, so there will be no 1164 space left over at the end. When we have all the symbols, we 1165 build the caller's pointer vector. */ 1166 1167 if (! dynamic) 1168 { 1169 hdr = &elf_tdata (abfd)->symtab_hdr; 1170 verhdr = NULL; 1171 } 1172 else 1173 { 1174 hdr = &elf_tdata (abfd)->dynsymtab_hdr; 1175 if (elf_dynversym (abfd) == 0) 1176 verhdr = NULL; 1177 else 1178 verhdr = &elf_tdata (abfd)->dynversym_hdr; 1179 if ((elf_dynverdef (abfd) != 0 1180 && elf_tdata (abfd)->verdef == NULL) 1181 || (elf_dynverref (abfd) != 0 1182 && elf_tdata (abfd)->verref == NULL)) 1183 { 1184 if (!_bfd_elf_slurp_version_tables (abfd, FALSE)) 1185 return -1; 1186 } 1187 } 1188 1189 ebd = get_elf_backend_data (abfd); 1190 symcount = hdr->sh_size / sizeof (Elf_External_Sym); 1191 if (symcount == 0) 1192 sym = symbase = NULL; 1193 else 1194 { 1195 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, symcount, 0, 1196 NULL, NULL, NULL); 1197 if (isymbuf == NULL) 1198 return -1; 1199 1200 amt = symcount; 1201 amt *= sizeof (elf_symbol_type); 1202 symbase = (elf_symbol_type *) bfd_zalloc (abfd, amt); 1203 if (symbase == (elf_symbol_type *) NULL) 1204 goto error_return; 1205 1206 /* Read the raw ELF version symbol information. */ 1207 if (verhdr != NULL 1208 && verhdr->sh_size / sizeof (Elf_External_Versym) != symcount) 1209 { 1210 _bfd_error_handler 1211 /* xgettext:c-format */ 1212 (_("%pB: version count (%" PRId64 ")" 1213 " does not match symbol count (%ld)"), 1214 abfd, 1215 (int64_t) (verhdr->sh_size / sizeof (Elf_External_Versym)), 1216 symcount); 1217 1218 /* Slurp in the symbols without the version information, 1219 since that is more helpful than just quitting. */ 1220 verhdr = NULL; 1221 } 1222 1223 if (verhdr != NULL) 1224 { 1225 if (bfd_seek (abfd, verhdr->sh_offset, SEEK_SET) != 0) 1226 goto error_return; 1227 1228 xverbuf = (Elf_External_Versym *) bfd_malloc (verhdr->sh_size); 1229 if (xverbuf == NULL && verhdr->sh_size != 0) 1230 goto error_return; 1231 1232 if (bfd_bread (xverbuf, verhdr->sh_size, abfd) != verhdr->sh_size) 1233 goto error_return; 1234 } 1235 1236 /* Skip first symbol, which is a null dummy. */ 1237 xver = xverbuf; 1238 if (xver != NULL) 1239 ++xver; 1240 isymend = isymbuf + symcount; 1241 for (isym = isymbuf + 1, sym = symbase; isym < isymend; isym++, sym++) 1242 { 1243 memcpy (&sym->internal_elf_sym, isym, sizeof (Elf_Internal_Sym)); 1244 1245 sym->symbol.the_bfd = abfd; 1246 sym->symbol.name = bfd_elf_sym_name (abfd, hdr, isym, NULL); 1247 sym->symbol.value = isym->st_value; 1248 1249 if (isym->st_shndx == SHN_UNDEF) 1250 { 1251 sym->symbol.section = bfd_und_section_ptr; 1252 } 1253 else if (isym->st_shndx == SHN_ABS) 1254 { 1255 sym->symbol.section = bfd_abs_section_ptr; 1256 } 1257 else if (isym->st_shndx == SHN_COMMON) 1258 { 1259 sym->symbol.section = bfd_com_section_ptr; 1260 if ((abfd->flags & BFD_PLUGIN) != 0) 1261 { 1262 asection *xc = bfd_get_section_by_name (abfd, "COMMON"); 1263 1264 if (xc == NULL) 1265 { 1266 flagword flags = (SEC_ALLOC | SEC_IS_COMMON | SEC_KEEP 1267 | SEC_EXCLUDE); 1268 xc = bfd_make_section_with_flags (abfd, "COMMON", flags); 1269 if (xc == NULL) 1270 goto error_return; 1271 } 1272 sym->symbol.section = xc; 1273 } 1274 /* Elf puts the alignment into the `value' field, and 1275 the size into the `size' field. BFD wants to see the 1276 size in the value field, and doesn't care (at the 1277 moment) about the alignment. */ 1278 sym->symbol.value = isym->st_size; 1279 } 1280 else 1281 { 1282 sym->symbol.section 1283 = bfd_section_from_elf_index (abfd, isym->st_shndx); 1284 if (sym->symbol.section == NULL) 1285 { 1286 /* This symbol is in a section for which we did not 1287 create a BFD section. Just use bfd_abs_section, 1288 although it is wrong. FIXME. */ 1289 sym->symbol.section = bfd_abs_section_ptr; 1290 } 1291 } 1292 1293 /* If this is a relocatable file, then the symbol value is 1294 already section relative. */ 1295 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0) 1296 sym->symbol.value -= sym->symbol.section->vma; 1297 1298 switch (ELF_ST_BIND (isym->st_info)) 1299 { 1300 case STB_LOCAL: 1301 sym->symbol.flags |= BSF_LOCAL; 1302 break; 1303 case STB_GLOBAL: 1304 if (isym->st_shndx != SHN_UNDEF && isym->st_shndx != SHN_COMMON) 1305 sym->symbol.flags |= BSF_GLOBAL; 1306 break; 1307 case STB_WEAK: 1308 sym->symbol.flags |= BSF_WEAK; 1309 break; 1310 case STB_GNU_UNIQUE: 1311 sym->symbol.flags |= BSF_GNU_UNIQUE; 1312 break; 1313 } 1314 1315 switch (ELF_ST_TYPE (isym->st_info)) 1316 { 1317 case STT_SECTION: 1318 sym->symbol.flags |= BSF_SECTION_SYM | BSF_DEBUGGING; 1319 break; 1320 case STT_FILE: 1321 sym->symbol.flags |= BSF_FILE | BSF_DEBUGGING; 1322 break; 1323 case STT_FUNC: 1324 sym->symbol.flags |= BSF_FUNCTION; 1325 break; 1326 case STT_COMMON: 1327 /* FIXME: Do we have to put the size field into the value field 1328 as we do with symbols in SHN_COMMON sections (see above) ? */ 1329 sym->symbol.flags |= BSF_ELF_COMMON; 1330 /* Fall through. */ 1331 case STT_OBJECT: 1332 sym->symbol.flags |= BSF_OBJECT; 1333 break; 1334 case STT_TLS: 1335 sym->symbol.flags |= BSF_THREAD_LOCAL; 1336 break; 1337 case STT_RELC: 1338 sym->symbol.flags |= BSF_RELC; 1339 break; 1340 case STT_SRELC: 1341 sym->symbol.flags |= BSF_SRELC; 1342 break; 1343 case STT_GNU_IFUNC: 1344 sym->symbol.flags |= BSF_GNU_INDIRECT_FUNCTION; 1345 break; 1346 } 1347 1348 if (dynamic) 1349 sym->symbol.flags |= BSF_DYNAMIC; 1350 1351 if (xver != NULL) 1352 { 1353 Elf_Internal_Versym iversym; 1354 1355 _bfd_elf_swap_versym_in (abfd, xver, &iversym); 1356 sym->version = iversym.vs_vers; 1357 xver++; 1358 } 1359 1360 /* Do some backend-specific processing on this symbol. */ 1361 if (ebd->elf_backend_symbol_processing) 1362 (*ebd->elf_backend_symbol_processing) (abfd, &sym->symbol); 1363 } 1364 } 1365 1366 /* Do some backend-specific processing on this symbol table. */ 1367 if (ebd->elf_backend_symbol_table_processing) 1368 (*ebd->elf_backend_symbol_table_processing) (abfd, symbase, symcount); 1369 1370 /* We rely on the zalloc to clear out the final symbol entry. */ 1371 1372 symcount = sym - symbase; 1373 1374 /* Fill in the user's symbol pointer vector if needed. */ 1375 if (symptrs) 1376 { 1377 long l = symcount; 1378 1379 sym = symbase; 1380 while (l-- > 0) 1381 { 1382 *symptrs++ = &sym->symbol; 1383 sym++; 1384 } 1385 *symptrs = 0; /* Final null pointer */ 1386 } 1387 1388 if (xverbuf != NULL) 1389 free (xverbuf); 1390 if (isymbuf != NULL && hdr->contents != (unsigned char *) isymbuf) 1391 free (isymbuf); 1392 return symcount; 1393 1394 error_return: 1395 if (xverbuf != NULL) 1396 free (xverbuf); 1397 if (isymbuf != NULL && hdr->contents != (unsigned char *) isymbuf) 1398 free (isymbuf); 1399 return -1; 1400 } 1401 1402 /* Read relocations for ASECT from REL_HDR. There are RELOC_COUNT of 1403 them. */ 1404 1405 static bfd_boolean 1406 elf_slurp_reloc_table_from_section (bfd *abfd, 1407 asection *asect, 1408 Elf_Internal_Shdr *rel_hdr, 1409 bfd_size_type reloc_count, 1410 arelent *relents, 1411 asymbol **symbols, 1412 bfd_boolean dynamic) 1413 { 1414 const struct elf_backend_data * const ebd = get_elf_backend_data (abfd); 1415 void *allocated = NULL; 1416 bfd_byte *native_relocs; 1417 arelent *relent; 1418 unsigned int i; 1419 int entsize; 1420 unsigned int symcount; 1421 1422 allocated = bfd_malloc (rel_hdr->sh_size); 1423 if (allocated == NULL) 1424 goto error_return; 1425 1426 if (bfd_seek (abfd, rel_hdr->sh_offset, SEEK_SET) != 0 1427 || (bfd_bread (allocated, rel_hdr->sh_size, abfd) 1428 != rel_hdr->sh_size)) 1429 goto error_return; 1430 1431 native_relocs = (bfd_byte *) allocated; 1432 1433 entsize = rel_hdr->sh_entsize; 1434 BFD_ASSERT (entsize == sizeof (Elf_External_Rel) 1435 || entsize == sizeof (Elf_External_Rela)); 1436 1437 if (dynamic) 1438 symcount = bfd_get_dynamic_symcount (abfd); 1439 else 1440 symcount = bfd_get_symcount (abfd); 1441 1442 for (i = 0, relent = relents; 1443 i < reloc_count; 1444 i++, relent++, native_relocs += entsize) 1445 { 1446 bfd_boolean res; 1447 Elf_Internal_Rela rela; 1448 1449 if (entsize == sizeof (Elf_External_Rela)) 1450 elf_swap_reloca_in (abfd, native_relocs, &rela); 1451 else 1452 elf_swap_reloc_in (abfd, native_relocs, &rela); 1453 1454 /* The address of an ELF reloc is section relative for an object 1455 file, and absolute for an executable file or shared library. 1456 The address of a normal BFD reloc is always section relative, 1457 and the address of a dynamic reloc is absolute.. */ 1458 if ((abfd->flags & (EXEC_P | DYNAMIC)) == 0 || dynamic) 1459 relent->address = rela.r_offset; 1460 else 1461 relent->address = rela.r_offset - asect->vma; 1462 1463 if (ELF_R_SYM (rela.r_info) == STN_UNDEF) 1464 /* FIXME: This and the error case below mean that we have a 1465 symbol on relocs that is not elf_symbol_type. */ 1466 relent->sym_ptr_ptr = bfd_abs_section_ptr->symbol_ptr_ptr; 1467 else if (ELF_R_SYM (rela.r_info) > symcount) 1468 { 1469 _bfd_error_handler 1470 /* xgettext:c-format */ 1471 (_("%pB(%pA): relocation %d has invalid symbol index %ld"), 1472 abfd, asect, i, (long) ELF_R_SYM (rela.r_info)); 1473 bfd_set_error (bfd_error_bad_value); 1474 relent->sym_ptr_ptr = bfd_abs_section_ptr->symbol_ptr_ptr; 1475 } 1476 else 1477 { 1478 asymbol **ps; 1479 1480 ps = symbols + ELF_R_SYM (rela.r_info) - 1; 1481 1482 relent->sym_ptr_ptr = ps; 1483 } 1484 1485 relent->addend = rela.r_addend; 1486 1487 if ((entsize == sizeof (Elf_External_Rela) 1488 && ebd->elf_info_to_howto != NULL) 1489 || ebd->elf_info_to_howto_rel == NULL) 1490 res = ebd->elf_info_to_howto (abfd, relent, &rela); 1491 else 1492 res = ebd->elf_info_to_howto_rel (abfd, relent, &rela); 1493 1494 if (! res || relent->howto == NULL) 1495 goto error_return; 1496 } 1497 1498 if (allocated != NULL) 1499 free (allocated); 1500 return TRUE; 1501 1502 error_return: 1503 if (allocated != NULL) 1504 free (allocated); 1505 return FALSE; 1506 } 1507 1508 /* Read in and swap the external relocs. */ 1509 1510 bfd_boolean 1511 elf_slurp_reloc_table (bfd *abfd, 1512 asection *asect, 1513 asymbol **symbols, 1514 bfd_boolean dynamic) 1515 { 1516 struct bfd_elf_section_data * const d = elf_section_data (asect); 1517 Elf_Internal_Shdr *rel_hdr; 1518 Elf_Internal_Shdr *rel_hdr2; 1519 bfd_size_type reloc_count; 1520 bfd_size_type reloc_count2; 1521 arelent *relents; 1522 bfd_size_type amt; 1523 1524 if (asect->relocation != NULL) 1525 return TRUE; 1526 1527 if (! dynamic) 1528 { 1529 if ((asect->flags & SEC_RELOC) == 0 1530 || asect->reloc_count == 0) 1531 return TRUE; 1532 1533 rel_hdr = d->rel.hdr; 1534 reloc_count = rel_hdr ? NUM_SHDR_ENTRIES (rel_hdr) : 0; 1535 rel_hdr2 = d->rela.hdr; 1536 reloc_count2 = rel_hdr2 ? NUM_SHDR_ENTRIES (rel_hdr2) : 0; 1537 1538 /* PR 17512: file: 0b4f81b7. */ 1539 if (asect->reloc_count != reloc_count + reloc_count2) 1540 return FALSE; 1541 BFD_ASSERT ((rel_hdr && asect->rel_filepos == rel_hdr->sh_offset) 1542 || (rel_hdr2 && asect->rel_filepos == rel_hdr2->sh_offset)); 1543 1544 } 1545 else 1546 { 1547 /* Note that ASECT->RELOC_COUNT tends not to be accurate in this 1548 case because relocations against this section may use the 1549 dynamic symbol table, and in that case bfd_section_from_shdr 1550 in elf.c does not update the RELOC_COUNT. */ 1551 if (asect->size == 0) 1552 return TRUE; 1553 1554 rel_hdr = &d->this_hdr; 1555 reloc_count = NUM_SHDR_ENTRIES (rel_hdr); 1556 rel_hdr2 = NULL; 1557 reloc_count2 = 0; 1558 } 1559 1560 amt = (reloc_count + reloc_count2) * sizeof (arelent); 1561 relents = (arelent *) bfd_alloc (abfd, amt); 1562 if (relents == NULL) 1563 return FALSE; 1564 1565 if (rel_hdr 1566 && !elf_slurp_reloc_table_from_section (abfd, asect, 1567 rel_hdr, reloc_count, 1568 relents, 1569 symbols, dynamic)) 1570 return FALSE; 1571 1572 if (rel_hdr2 1573 && !elf_slurp_reloc_table_from_section (abfd, asect, 1574 rel_hdr2, reloc_count2, 1575 relents + reloc_count, 1576 symbols, dynamic)) 1577 return FALSE; 1578 1579 asect->relocation = relents; 1580 return TRUE; 1581 } 1582 1583 #if DEBUG & 2 1584 static void 1585 elf_debug_section (int num, Elf_Internal_Shdr *hdr) 1586 { 1587 fprintf (stderr, "\nSection#%d '%s' 0x%.8lx\n", num, 1588 hdr->bfd_section != NULL ? hdr->bfd_section->name : "", 1589 (long) hdr); 1590 fprintf (stderr, 1591 "sh_name = %ld\tsh_type = %ld\tsh_flags = %ld\n", 1592 (long) hdr->sh_name, 1593 (long) hdr->sh_type, 1594 (long) hdr->sh_flags); 1595 fprintf (stderr, 1596 "sh_addr = %ld\tsh_offset = %ld\tsh_size = %ld\n", 1597 (long) hdr->sh_addr, 1598 (long) hdr->sh_offset, 1599 (long) hdr->sh_size); 1600 fprintf (stderr, 1601 "sh_link = %ld\tsh_info = %ld\tsh_addralign = %ld\n", 1602 (long) hdr->sh_link, 1603 (long) hdr->sh_info, 1604 (long) hdr->sh_addralign); 1605 fprintf (stderr, "sh_entsize = %ld\n", 1606 (long) hdr->sh_entsize); 1607 fflush (stderr); 1608 } 1609 #endif 1610 1611 #if DEBUG & 1 1612 static void 1613 elf_debug_file (Elf_Internal_Ehdr *ehdrp) 1614 { 1615 fprintf (stderr, "e_entry = 0x%.8lx\n", (long) ehdrp->e_entry); 1616 fprintf (stderr, "e_phoff = %ld\n", (long) ehdrp->e_phoff); 1617 fprintf (stderr, "e_phnum = %ld\n", (long) ehdrp->e_phnum); 1618 fprintf (stderr, "e_phentsize = %ld\n", (long) ehdrp->e_phentsize); 1619 fprintf (stderr, "e_shoff = %ld\n", (long) ehdrp->e_shoff); 1620 fprintf (stderr, "e_shnum = %ld\n", (long) ehdrp->e_shnum); 1621 fprintf (stderr, "e_shentsize = %ld\n", (long) ehdrp->e_shentsize); 1622 } 1623 #endif 1624 1625 /* Create a new BFD as if by bfd_openr. Rather than opening a file, 1626 reconstruct an ELF file by reading the segments out of remote 1627 memory based on the ELF file header at EHDR_VMA and the ELF program 1628 headers it points to. If non-zero, SIZE is the known extent of the 1629 object. If not null, *LOADBASEP is filled in with the difference 1630 between the VMAs from which the segments were read, and the VMAs 1631 the file headers (and hence BFD's idea of each section's VMA) put 1632 them at. 1633 1634 The function TARGET_READ_MEMORY is called to copy LEN bytes from 1635 the remote memory at target address VMA into the local buffer at 1636 MYADDR; it should return zero on success or an `errno' code on 1637 failure. TEMPL must be a BFD for a target with the word size and 1638 byte order found in the remote memory. */ 1639 1640 bfd * 1641 NAME(_bfd_elf,bfd_from_remote_memory) 1642 (bfd *templ, 1643 bfd_vma ehdr_vma, 1644 bfd_size_type size, 1645 bfd_vma *loadbasep, 1646 int (*target_read_memory) (bfd_vma, bfd_byte *, bfd_size_type)) 1647 { 1648 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */ 1649 Elf_Internal_Ehdr i_ehdr; /* Elf file header, internal form */ 1650 Elf_External_Phdr *x_phdrs; 1651 Elf_Internal_Phdr *i_phdrs, *last_phdr, *first_phdr; 1652 bfd *nbfd; 1653 struct bfd_in_memory *bim; 1654 bfd_byte *contents; 1655 int err; 1656 unsigned int i; 1657 bfd_vma high_offset; 1658 bfd_vma shdr_end; 1659 bfd_vma loadbase; 1660 1661 /* Read in the ELF header in external format. */ 1662 err = target_read_memory (ehdr_vma, (bfd_byte *) &x_ehdr, sizeof x_ehdr); 1663 if (err) 1664 { 1665 bfd_set_error (bfd_error_system_call); 1666 errno = err; 1667 return NULL; 1668 } 1669 1670 /* Now check to see if we have a valid ELF file, and one that BFD can 1671 make use of. The magic number must match, the address size ('class') 1672 and byte-swapping must match our XVEC entry. */ 1673 1674 if (! elf_file_p (&x_ehdr) 1675 || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT 1676 || x_ehdr.e_ident[EI_CLASS] != ELFCLASS) 1677 { 1678 bfd_set_error (bfd_error_wrong_format); 1679 return NULL; 1680 } 1681 1682 /* Check that file's byte order matches xvec's */ 1683 switch (x_ehdr.e_ident[EI_DATA]) 1684 { 1685 case ELFDATA2MSB: /* Big-endian */ 1686 if (! bfd_header_big_endian (templ)) 1687 { 1688 bfd_set_error (bfd_error_wrong_format); 1689 return NULL; 1690 } 1691 break; 1692 case ELFDATA2LSB: /* Little-endian */ 1693 if (! bfd_header_little_endian (templ)) 1694 { 1695 bfd_set_error (bfd_error_wrong_format); 1696 return NULL; 1697 } 1698 break; 1699 case ELFDATANONE: /* No data encoding specified */ 1700 default: /* Unknown data encoding specified */ 1701 bfd_set_error (bfd_error_wrong_format); 1702 return NULL; 1703 } 1704 1705 elf_swap_ehdr_in (templ, &x_ehdr, &i_ehdr); 1706 1707 /* The file header tells where to find the program headers. 1708 These are what we use to actually choose what to read. */ 1709 1710 if (i_ehdr.e_phentsize != sizeof (Elf_External_Phdr) || i_ehdr.e_phnum == 0) 1711 { 1712 bfd_set_error (bfd_error_wrong_format); 1713 return NULL; 1714 } 1715 1716 x_phdrs = (Elf_External_Phdr *) 1717 bfd_malloc (i_ehdr.e_phnum * (sizeof *x_phdrs + sizeof *i_phdrs)); 1718 if (x_phdrs == NULL) 1719 return NULL; 1720 err = target_read_memory (ehdr_vma + i_ehdr.e_phoff, (bfd_byte *) x_phdrs, 1721 i_ehdr.e_phnum * sizeof x_phdrs[0]); 1722 if (err) 1723 { 1724 free (x_phdrs); 1725 bfd_set_error (bfd_error_system_call); 1726 errno = err; 1727 return NULL; 1728 } 1729 i_phdrs = (Elf_Internal_Phdr *) &x_phdrs[i_ehdr.e_phnum]; 1730 1731 high_offset = 0; 1732 loadbase = 0; 1733 first_phdr = NULL; 1734 last_phdr = NULL; 1735 for (i = 0; i < i_ehdr.e_phnum; ++i) 1736 { 1737 elf_swap_phdr_in (templ, &x_phdrs[i], &i_phdrs[i]); 1738 if (i_phdrs[i].p_type == PT_LOAD) 1739 { 1740 bfd_vma segment_end = i_phdrs[i].p_offset + i_phdrs[i].p_filesz; 1741 1742 if (segment_end > high_offset) 1743 { 1744 high_offset = segment_end; 1745 last_phdr = &i_phdrs[i]; 1746 } 1747 1748 /* If this program header covers offset zero, where the file 1749 header sits, then we can figure out the loadbase. */ 1750 if (first_phdr == NULL) 1751 { 1752 bfd_vma p_offset = i_phdrs[i].p_offset; 1753 bfd_vma p_vaddr = i_phdrs[i].p_vaddr; 1754 1755 if (i_phdrs[i].p_align > 1) 1756 { 1757 p_offset &= -i_phdrs[i].p_align; 1758 p_vaddr &= -i_phdrs[i].p_align; 1759 } 1760 if (p_offset == 0) 1761 { 1762 loadbase = ehdr_vma - p_vaddr; 1763 first_phdr = &i_phdrs[i]; 1764 } 1765 } 1766 } 1767 } 1768 if (high_offset == 0) 1769 { 1770 /* There were no PT_LOAD segments, so we don't have anything to read. */ 1771 free (x_phdrs); 1772 bfd_set_error (bfd_error_wrong_format); 1773 return NULL; 1774 } 1775 1776 shdr_end = 0; 1777 if (i_ehdr.e_shoff != 0 && i_ehdr.e_shnum != 0 && i_ehdr.e_shentsize != 0) 1778 { 1779 shdr_end = i_ehdr.e_shoff + i_ehdr.e_shnum * i_ehdr.e_shentsize; 1780 1781 if (last_phdr->p_filesz != last_phdr->p_memsz) 1782 { 1783 /* If the last PT_LOAD header has a bss area then ld.so will 1784 have cleared anything past p_filesz, zapping the section 1785 headers. */ 1786 } 1787 else if (size >= shdr_end) 1788 high_offset = size; 1789 else 1790 { 1791 bfd_vma page_size = get_elf_backend_data (templ)->minpagesize; 1792 bfd_vma segment_end = last_phdr->p_offset + last_phdr->p_filesz; 1793 1794 /* Assume we loaded full pages, allowing us to sometimes see 1795 section headers. */ 1796 if (page_size > 1 && shdr_end > segment_end) 1797 { 1798 bfd_vma page_end = (segment_end + page_size - 1) & -page_size; 1799 1800 if (page_end >= shdr_end) 1801 /* Whee, section headers covered. */ 1802 high_offset = shdr_end; 1803 } 1804 } 1805 } 1806 1807 /* Now we know the size of the whole image we want read in. */ 1808 contents = (bfd_byte *) bfd_zmalloc (high_offset); 1809 if (contents == NULL) 1810 { 1811 free (x_phdrs); 1812 return NULL; 1813 } 1814 1815 for (i = 0; i < i_ehdr.e_phnum; ++i) 1816 if (i_phdrs[i].p_type == PT_LOAD) 1817 { 1818 bfd_vma start = i_phdrs[i].p_offset; 1819 bfd_vma end = start + i_phdrs[i].p_filesz; 1820 bfd_vma vaddr = i_phdrs[i].p_vaddr; 1821 1822 /* Extend the beginning of the first pt_load to cover file 1823 header and program headers, if we proved earlier that its 1824 aligned offset is 0. */ 1825 if (first_phdr == &i_phdrs[i]) 1826 { 1827 vaddr -= start; 1828 start = 0; 1829 } 1830 /* Extend the end of the last pt_load to cover section headers. */ 1831 if (last_phdr == &i_phdrs[i]) 1832 end = high_offset; 1833 err = target_read_memory (loadbase + vaddr, 1834 contents + start, end - start); 1835 if (err) 1836 { 1837 free (x_phdrs); 1838 free (contents); 1839 bfd_set_error (bfd_error_system_call); 1840 errno = err; 1841 return NULL; 1842 } 1843 } 1844 free (x_phdrs); 1845 1846 /* If the segments visible in memory didn't include the section headers, 1847 then clear them from the file header. */ 1848 if (high_offset < shdr_end) 1849 { 1850 memset (&x_ehdr.e_shoff, 0, sizeof x_ehdr.e_shoff); 1851 memset (&x_ehdr.e_shnum, 0, sizeof x_ehdr.e_shnum); 1852 memset (&x_ehdr.e_shstrndx, 0, sizeof x_ehdr.e_shstrndx); 1853 } 1854 1855 /* This will normally have been in the first PT_LOAD segment. But it 1856 conceivably could be missing, and we might have just changed it. */ 1857 memcpy (contents, &x_ehdr, sizeof x_ehdr); 1858 1859 /* Now we have a memory image of the ELF file contents. Make a BFD. */ 1860 bim = (struct bfd_in_memory *) bfd_malloc (sizeof (struct bfd_in_memory)); 1861 if (bim == NULL) 1862 { 1863 free (contents); 1864 return NULL; 1865 } 1866 nbfd = _bfd_new_bfd (); 1867 if (nbfd == NULL) 1868 { 1869 free (bim); 1870 free (contents); 1871 return NULL; 1872 } 1873 nbfd->filename = xstrdup ("<in-memory>"); 1874 nbfd->xvec = templ->xvec; 1875 bim->size = high_offset; 1876 bim->buffer = contents; 1877 nbfd->iostream = bim; 1878 nbfd->flags = BFD_IN_MEMORY; 1879 nbfd->iovec = &_bfd_memory_iovec; 1880 nbfd->origin = 0; 1881 nbfd->direction = read_direction; 1882 nbfd->mtime = time (NULL); 1883 nbfd->mtime_set = TRUE; 1884 1885 if (loadbasep) 1886 *loadbasep = loadbase; 1887 return nbfd; 1888 } 1889 1890 /* Function for ELF_R_INFO. */ 1891 1892 bfd_vma 1893 NAME(elf,r_info) (bfd_vma sym, bfd_vma type) 1894 { 1895 return ELF_R_INFO (sym, type); 1896 } 1897 1898 /* Function for ELF_R_SYM. */ 1899 1900 bfd_vma 1901 NAME(elf,r_sym) (bfd_vma r_info) 1902 { 1903 return ELF_R_SYM (r_info); 1904 } 1905 1906 #include "elfcore.h" 1907 1908 /* Size-dependent data and functions. */ 1909 const struct elf_size_info NAME(_bfd_elf,size_info) = { 1910 sizeof (Elf_External_Ehdr), 1911 sizeof (Elf_External_Phdr), 1912 sizeof (Elf_External_Shdr), 1913 sizeof (Elf_External_Rel), 1914 sizeof (Elf_External_Rela), 1915 sizeof (Elf_External_Sym), 1916 sizeof (Elf_External_Dyn), 1917 sizeof (Elf_External_Note), 1918 4, 1919 1, 1920 ARCH_SIZE, LOG_FILE_ALIGN, 1921 ELFCLASS, EV_CURRENT, 1922 elf_write_out_phdrs, 1923 elf_write_shdrs_and_ehdr, 1924 elf_checksum_contents, 1925 elf_write_relocs, 1926 elf_swap_symbol_in, 1927 elf_swap_symbol_out, 1928 elf_slurp_reloc_table, 1929 elf_slurp_symbol_table, 1930 elf_swap_dyn_in, 1931 elf_swap_dyn_out, 1932 elf_swap_reloc_in, 1933 elf_swap_reloc_out, 1934 elf_swap_reloca_in, 1935 elf_swap_reloca_out 1936 }; 1937