1 /* ELF executable support for BFD. 2 Copyright (C) 1991-2018 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 if (ptr->howto == NULL) 962 { 963 *failedp = TRUE; 964 return; 965 } 966 967 src_rela.r_offset = ptr->address + addr_offset; 968 src_rela.r_info = ELF_R_INFO (n, ptr->howto->type); 969 src_rela.r_addend = ptr->addend; 970 (*swap_out) (abfd, &src_rela, dst_rela); 971 } 972 } 973 974 /* Write out the program headers. */ 975 976 int 977 elf_write_out_phdrs (bfd *abfd, 978 const Elf_Internal_Phdr *phdr, 979 unsigned int count) 980 { 981 while (count--) 982 { 983 Elf_External_Phdr extphdr; 984 985 elf_swap_phdr_out (abfd, phdr, &extphdr); 986 if (bfd_bwrite (&extphdr, sizeof (Elf_External_Phdr), abfd) 987 != sizeof (Elf_External_Phdr)) 988 return -1; 989 phdr++; 990 } 991 return 0; 992 } 993 994 /* Write out the section headers and the ELF file header. */ 995 996 bfd_boolean 997 elf_write_shdrs_and_ehdr (bfd *abfd) 998 { 999 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */ 1000 Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form */ 1001 Elf_External_Shdr *x_shdrp; /* Section header table, external form */ 1002 Elf_Internal_Shdr **i_shdrp; /* Section header table, internal form */ 1003 unsigned int count; 1004 bfd_size_type amt; 1005 1006 i_ehdrp = elf_elfheader (abfd); 1007 i_shdrp = elf_elfsections (abfd); 1008 1009 /* swap the header before spitting it out... */ 1010 1011 #if DEBUG & 1 1012 elf_debug_file (i_ehdrp); 1013 #endif 1014 elf_swap_ehdr_out (abfd, i_ehdrp, &x_ehdr); 1015 amt = sizeof (x_ehdr); 1016 if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0 1017 || bfd_bwrite (&x_ehdr, amt, abfd) != amt) 1018 return FALSE; 1019 1020 /* Some fields in the first section header handle overflow of ehdr 1021 fields. */ 1022 if (i_ehdrp->e_phnum >= PN_XNUM) 1023 i_shdrp[0]->sh_info = i_ehdrp->e_phnum; 1024 if (i_ehdrp->e_shnum >= (SHN_LORESERVE & 0xffff)) 1025 i_shdrp[0]->sh_size = i_ehdrp->e_shnum; 1026 if (i_ehdrp->e_shstrndx >= (SHN_LORESERVE & 0xffff)) 1027 i_shdrp[0]->sh_link = i_ehdrp->e_shstrndx; 1028 1029 /* at this point we've concocted all the ELF sections... */ 1030 amt = i_ehdrp->e_shnum; 1031 amt *= sizeof (*x_shdrp); 1032 x_shdrp = (Elf_External_Shdr *) bfd_alloc (abfd, amt); 1033 if (!x_shdrp) 1034 return FALSE; 1035 1036 for (count = 0; count < i_ehdrp->e_shnum; i_shdrp++, count++) 1037 { 1038 #if DEBUG & 2 1039 elf_debug_section (count, *i_shdrp); 1040 #endif 1041 elf_swap_shdr_out (abfd, *i_shdrp, x_shdrp + count); 1042 } 1043 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_shoff, SEEK_SET) != 0 1044 || bfd_bwrite (x_shdrp, amt, abfd) != amt) 1045 return FALSE; 1046 1047 /* need to dump the string table too... */ 1048 1049 return TRUE; 1050 } 1051 1052 bfd_boolean 1053 elf_checksum_contents (bfd *abfd, 1054 void (*process) (const void *, size_t, void *), 1055 void *arg) 1056 { 1057 Elf_Internal_Ehdr *i_ehdrp = elf_elfheader (abfd); 1058 Elf_Internal_Shdr **i_shdrp = elf_elfsections (abfd); 1059 Elf_Internal_Phdr *i_phdrp = elf_tdata (abfd)->phdr; 1060 unsigned int count, num; 1061 1062 { 1063 Elf_External_Ehdr x_ehdr; 1064 Elf_Internal_Ehdr i_ehdr; 1065 1066 i_ehdr = *i_ehdrp; 1067 i_ehdr.e_phoff = i_ehdr.e_shoff = 0; 1068 elf_swap_ehdr_out (abfd, &i_ehdr, &x_ehdr); 1069 (*process) (&x_ehdr, sizeof x_ehdr, arg); 1070 } 1071 1072 num = i_ehdrp->e_phnum; 1073 for (count = 0; count < num; count++) 1074 { 1075 Elf_External_Phdr x_phdr; 1076 elf_swap_phdr_out (abfd, &i_phdrp[count], &x_phdr); 1077 (*process) (&x_phdr, sizeof x_phdr, arg); 1078 } 1079 1080 num = elf_numsections (abfd); 1081 for (count = 0; count < num; count++) 1082 { 1083 Elf_Internal_Shdr i_shdr; 1084 Elf_External_Shdr x_shdr; 1085 bfd_byte *contents, *free_contents; 1086 1087 i_shdr = *i_shdrp[count]; 1088 i_shdr.sh_offset = 0; 1089 1090 elf_swap_shdr_out (abfd, &i_shdr, &x_shdr); 1091 (*process) (&x_shdr, sizeof x_shdr, arg); 1092 1093 /* Process the section's contents, if it has some. 1094 PR ld/12451: Read them in if necessary. */ 1095 if (i_shdr.sh_type == SHT_NOBITS) 1096 continue; 1097 free_contents = NULL; 1098 contents = i_shdr.contents; 1099 if (contents == NULL) 1100 { 1101 asection *sec; 1102 1103 sec = bfd_section_from_elf_index (abfd, count); 1104 if (sec != NULL) 1105 { 1106 contents = sec->contents; 1107 if (contents == NULL) 1108 { 1109 /* Force rereading from file. */ 1110 sec->flags &= ~SEC_IN_MEMORY; 1111 if (!bfd_malloc_and_get_section (abfd, sec, &free_contents)) 1112 continue; 1113 contents = free_contents; 1114 } 1115 } 1116 } 1117 if (contents != NULL) 1118 { 1119 (*process) (contents, i_shdr.sh_size, arg); 1120 if (free_contents != NULL) 1121 free (free_contents); 1122 } 1123 } 1124 1125 return TRUE; 1126 } 1127 1128 long 1129 elf_slurp_symbol_table (bfd *abfd, asymbol **symptrs, bfd_boolean dynamic) 1130 { 1131 Elf_Internal_Shdr *hdr; 1132 Elf_Internal_Shdr *verhdr; 1133 unsigned long symcount; /* Number of external ELF symbols */ 1134 elf_symbol_type *sym; /* Pointer to current bfd symbol */ 1135 elf_symbol_type *symbase; /* Buffer for generated bfd symbols */ 1136 Elf_Internal_Sym *isym; 1137 Elf_Internal_Sym *isymend; 1138 Elf_Internal_Sym *isymbuf = NULL; 1139 Elf_External_Versym *xver; 1140 Elf_External_Versym *xverbuf = NULL; 1141 const struct elf_backend_data *ebd; 1142 bfd_size_type amt; 1143 1144 /* Read each raw ELF symbol, converting from external ELF form to 1145 internal ELF form, and then using the information to create a 1146 canonical bfd symbol table entry. 1147 1148 Note that we allocate the initial bfd canonical symbol buffer 1149 based on a one-to-one mapping of the ELF symbols to canonical 1150 symbols. We actually use all the ELF symbols, so there will be no 1151 space left over at the end. When we have all the symbols, we 1152 build the caller's pointer vector. */ 1153 1154 if (! dynamic) 1155 { 1156 hdr = &elf_tdata (abfd)->symtab_hdr; 1157 verhdr = NULL; 1158 } 1159 else 1160 { 1161 hdr = &elf_tdata (abfd)->dynsymtab_hdr; 1162 if (elf_dynversym (abfd) == 0) 1163 verhdr = NULL; 1164 else 1165 verhdr = &elf_tdata (abfd)->dynversym_hdr; 1166 if ((elf_dynverdef (abfd) != 0 1167 && elf_tdata (abfd)->verdef == NULL) 1168 || (elf_dynverref (abfd) != 0 1169 && elf_tdata (abfd)->verref == NULL)) 1170 { 1171 if (!_bfd_elf_slurp_version_tables (abfd, FALSE)) 1172 return -1; 1173 } 1174 } 1175 1176 ebd = get_elf_backend_data (abfd); 1177 symcount = hdr->sh_size / sizeof (Elf_External_Sym); 1178 if (symcount == 0) 1179 sym = symbase = NULL; 1180 else 1181 { 1182 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, symcount, 0, 1183 NULL, NULL, NULL); 1184 if (isymbuf == NULL) 1185 return -1; 1186 1187 amt = symcount; 1188 amt *= sizeof (elf_symbol_type); 1189 symbase = (elf_symbol_type *) bfd_zalloc (abfd, amt); 1190 if (symbase == (elf_symbol_type *) NULL) 1191 goto error_return; 1192 1193 /* Read the raw ELF version symbol information. */ 1194 if (verhdr != NULL 1195 && verhdr->sh_size / sizeof (Elf_External_Versym) != symcount) 1196 { 1197 _bfd_error_handler 1198 /* xgettext:c-format */ 1199 (_("%B: version count (%Ld) does not match symbol count (%ld)"), 1200 abfd, 1201 verhdr->sh_size / sizeof (Elf_External_Versym), 1202 symcount); 1203 1204 /* Slurp in the symbols without the version information, 1205 since that is more helpful than just quitting. */ 1206 verhdr = NULL; 1207 } 1208 1209 if (verhdr != NULL) 1210 { 1211 if (bfd_seek (abfd, verhdr->sh_offset, SEEK_SET) != 0) 1212 goto error_return; 1213 1214 xverbuf = (Elf_External_Versym *) bfd_malloc (verhdr->sh_size); 1215 if (xverbuf == NULL && verhdr->sh_size != 0) 1216 goto error_return; 1217 1218 if (bfd_bread (xverbuf, verhdr->sh_size, abfd) != verhdr->sh_size) 1219 goto error_return; 1220 } 1221 1222 /* Skip first symbol, which is a null dummy. */ 1223 xver = xverbuf; 1224 if (xver != NULL) 1225 ++xver; 1226 isymend = isymbuf + symcount; 1227 for (isym = isymbuf + 1, sym = symbase; isym < isymend; isym++, sym++) 1228 { 1229 memcpy (&sym->internal_elf_sym, isym, sizeof (Elf_Internal_Sym)); 1230 1231 sym->symbol.the_bfd = abfd; 1232 sym->symbol.name = bfd_elf_sym_name (abfd, hdr, isym, NULL); 1233 sym->symbol.value = isym->st_value; 1234 1235 if (isym->st_shndx == SHN_UNDEF) 1236 { 1237 sym->symbol.section = bfd_und_section_ptr; 1238 } 1239 else if (isym->st_shndx == SHN_ABS) 1240 { 1241 sym->symbol.section = bfd_abs_section_ptr; 1242 } 1243 else if (isym->st_shndx == SHN_COMMON) 1244 { 1245 sym->symbol.section = bfd_com_section_ptr; 1246 if ((abfd->flags & BFD_PLUGIN) != 0) 1247 { 1248 asection *xc = bfd_get_section_by_name (abfd, "COMMON"); 1249 1250 if (xc == NULL) 1251 { 1252 flagword flags = (SEC_ALLOC | SEC_IS_COMMON | SEC_KEEP 1253 | SEC_EXCLUDE); 1254 xc = bfd_make_section_with_flags (abfd, "COMMON", flags); 1255 if (xc == NULL) 1256 goto error_return; 1257 } 1258 sym->symbol.section = xc; 1259 } 1260 /* Elf puts the alignment into the `value' field, and 1261 the size into the `size' field. BFD wants to see the 1262 size in the value field, and doesn't care (at the 1263 moment) about the alignment. */ 1264 sym->symbol.value = isym->st_size; 1265 } 1266 else 1267 { 1268 sym->symbol.section 1269 = bfd_section_from_elf_index (abfd, isym->st_shndx); 1270 if (sym->symbol.section == NULL) 1271 { 1272 /* This symbol is in a section for which we did not 1273 create a BFD section. Just use bfd_abs_section, 1274 although it is wrong. FIXME. */ 1275 sym->symbol.section = bfd_abs_section_ptr; 1276 } 1277 } 1278 1279 /* If this is a relocatable file, then the symbol value is 1280 already section relative. */ 1281 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0) 1282 sym->symbol.value -= sym->symbol.section->vma; 1283 1284 switch (ELF_ST_BIND (isym->st_info)) 1285 { 1286 case STB_LOCAL: 1287 sym->symbol.flags |= BSF_LOCAL; 1288 break; 1289 case STB_GLOBAL: 1290 if (isym->st_shndx != SHN_UNDEF && isym->st_shndx != SHN_COMMON) 1291 sym->symbol.flags |= BSF_GLOBAL; 1292 break; 1293 case STB_WEAK: 1294 sym->symbol.flags |= BSF_WEAK; 1295 break; 1296 case STB_GNU_UNIQUE: 1297 sym->symbol.flags |= BSF_GNU_UNIQUE; 1298 break; 1299 } 1300 1301 switch (ELF_ST_TYPE (isym->st_info)) 1302 { 1303 case STT_SECTION: 1304 sym->symbol.flags |= BSF_SECTION_SYM | BSF_DEBUGGING; 1305 break; 1306 case STT_FILE: 1307 sym->symbol.flags |= BSF_FILE | BSF_DEBUGGING; 1308 break; 1309 case STT_FUNC: 1310 sym->symbol.flags |= BSF_FUNCTION; 1311 break; 1312 case STT_COMMON: 1313 /* FIXME: Do we have to put the size field into the value field 1314 as we do with symbols in SHN_COMMON sections (see above) ? */ 1315 sym->symbol.flags |= BSF_ELF_COMMON; 1316 /* Fall through. */ 1317 case STT_OBJECT: 1318 sym->symbol.flags |= BSF_OBJECT; 1319 break; 1320 case STT_TLS: 1321 sym->symbol.flags |= BSF_THREAD_LOCAL; 1322 break; 1323 case STT_RELC: 1324 sym->symbol.flags |= BSF_RELC; 1325 break; 1326 case STT_SRELC: 1327 sym->symbol.flags |= BSF_SRELC; 1328 break; 1329 case STT_GNU_IFUNC: 1330 sym->symbol.flags |= BSF_GNU_INDIRECT_FUNCTION; 1331 break; 1332 } 1333 1334 if (dynamic) 1335 sym->symbol.flags |= BSF_DYNAMIC; 1336 1337 if (xver != NULL) 1338 { 1339 Elf_Internal_Versym iversym; 1340 1341 _bfd_elf_swap_versym_in (abfd, xver, &iversym); 1342 sym->version = iversym.vs_vers; 1343 xver++; 1344 } 1345 1346 /* Do some backend-specific processing on this symbol. */ 1347 if (ebd->elf_backend_symbol_processing) 1348 (*ebd->elf_backend_symbol_processing) (abfd, &sym->symbol); 1349 } 1350 } 1351 1352 /* Do some backend-specific processing on this symbol table. */ 1353 if (ebd->elf_backend_symbol_table_processing) 1354 (*ebd->elf_backend_symbol_table_processing) (abfd, symbase, symcount); 1355 1356 /* We rely on the zalloc to clear out the final symbol entry. */ 1357 1358 symcount = sym - symbase; 1359 1360 /* Fill in the user's symbol pointer vector if needed. */ 1361 if (symptrs) 1362 { 1363 long l = symcount; 1364 1365 sym = symbase; 1366 while (l-- > 0) 1367 { 1368 *symptrs++ = &sym->symbol; 1369 sym++; 1370 } 1371 *symptrs = 0; /* Final null pointer */ 1372 } 1373 1374 if (xverbuf != NULL) 1375 free (xverbuf); 1376 if (isymbuf != NULL && hdr->contents != (unsigned char *) isymbuf) 1377 free (isymbuf); 1378 return symcount; 1379 1380 error_return: 1381 if (xverbuf != NULL) 1382 free (xverbuf); 1383 if (isymbuf != NULL && hdr->contents != (unsigned char *) isymbuf) 1384 free (isymbuf); 1385 return -1; 1386 } 1387 1388 /* Read relocations for ASECT from REL_HDR. There are RELOC_COUNT of 1389 them. */ 1390 1391 static bfd_boolean 1392 elf_slurp_reloc_table_from_section (bfd *abfd, 1393 asection *asect, 1394 Elf_Internal_Shdr *rel_hdr, 1395 bfd_size_type reloc_count, 1396 arelent *relents, 1397 asymbol **symbols, 1398 bfd_boolean dynamic) 1399 { 1400 const struct elf_backend_data * const ebd = get_elf_backend_data (abfd); 1401 void *allocated = NULL; 1402 bfd_byte *native_relocs; 1403 arelent *relent; 1404 unsigned int i; 1405 int entsize; 1406 unsigned int symcount; 1407 1408 allocated = bfd_malloc (rel_hdr->sh_size); 1409 if (allocated == NULL) 1410 goto error_return; 1411 1412 if (bfd_seek (abfd, rel_hdr->sh_offset, SEEK_SET) != 0 1413 || (bfd_bread (allocated, rel_hdr->sh_size, abfd) 1414 != rel_hdr->sh_size)) 1415 goto error_return; 1416 1417 native_relocs = (bfd_byte *) allocated; 1418 1419 entsize = rel_hdr->sh_entsize; 1420 BFD_ASSERT (entsize == sizeof (Elf_External_Rel) 1421 || entsize == sizeof (Elf_External_Rela)); 1422 1423 if (dynamic) 1424 symcount = bfd_get_dynamic_symcount (abfd); 1425 else 1426 symcount = bfd_get_symcount (abfd); 1427 1428 for (i = 0, relent = relents; 1429 i < reloc_count; 1430 i++, relent++, native_relocs += entsize) 1431 { 1432 Elf_Internal_Rela rela; 1433 1434 if (entsize == sizeof (Elf_External_Rela)) 1435 elf_swap_reloca_in (abfd, native_relocs, &rela); 1436 else 1437 elf_swap_reloc_in (abfd, native_relocs, &rela); 1438 1439 /* The address of an ELF reloc is section relative for an object 1440 file, and absolute for an executable file or shared library. 1441 The address of a normal BFD reloc is always section relative, 1442 and the address of a dynamic reloc is absolute.. */ 1443 if ((abfd->flags & (EXEC_P | DYNAMIC)) == 0 || dynamic) 1444 relent->address = rela.r_offset; 1445 else 1446 relent->address = rela.r_offset - asect->vma; 1447 1448 if (ELF_R_SYM (rela.r_info) == STN_UNDEF) 1449 /* FIXME: This and the error case below mean that we have a 1450 symbol on relocs that is not elf_symbol_type. */ 1451 relent->sym_ptr_ptr = bfd_abs_section_ptr->symbol_ptr_ptr; 1452 else if (ELF_R_SYM (rela.r_info) > symcount) 1453 { 1454 _bfd_error_handler 1455 /* xgettext:c-format */ 1456 (_("%B(%A): relocation %d has invalid symbol index %ld"), 1457 abfd, asect, i, (long) ELF_R_SYM (rela.r_info)); 1458 relent->sym_ptr_ptr = bfd_abs_section_ptr->symbol_ptr_ptr; 1459 } 1460 else 1461 { 1462 asymbol **ps; 1463 1464 ps = symbols + ELF_R_SYM (rela.r_info) - 1; 1465 1466 relent->sym_ptr_ptr = ps; 1467 } 1468 1469 relent->addend = rela.r_addend; 1470 1471 if ((entsize == sizeof (Elf_External_Rela) 1472 && ebd->elf_info_to_howto != NULL) 1473 || ebd->elf_info_to_howto_rel == NULL) 1474 (*ebd->elf_info_to_howto) (abfd, relent, &rela); 1475 else 1476 (*ebd->elf_info_to_howto_rel) (abfd, relent, &rela); 1477 } 1478 1479 if (allocated != NULL) 1480 free (allocated); 1481 1482 return TRUE; 1483 1484 error_return: 1485 if (allocated != NULL) 1486 free (allocated); 1487 return FALSE; 1488 } 1489 1490 /* Read in and swap the external relocs. */ 1491 1492 bfd_boolean 1493 elf_slurp_reloc_table (bfd *abfd, 1494 asection *asect, 1495 asymbol **symbols, 1496 bfd_boolean dynamic) 1497 { 1498 struct bfd_elf_section_data * const d = elf_section_data (asect); 1499 Elf_Internal_Shdr *rel_hdr; 1500 Elf_Internal_Shdr *rel_hdr2; 1501 bfd_size_type reloc_count; 1502 bfd_size_type reloc_count2; 1503 arelent *relents; 1504 bfd_size_type amt; 1505 1506 if (asect->relocation != NULL) 1507 return TRUE; 1508 1509 if (! dynamic) 1510 { 1511 if ((asect->flags & SEC_RELOC) == 0 1512 || asect->reloc_count == 0) 1513 return TRUE; 1514 1515 rel_hdr = d->rel.hdr; 1516 reloc_count = rel_hdr ? NUM_SHDR_ENTRIES (rel_hdr) : 0; 1517 rel_hdr2 = d->rela.hdr; 1518 reloc_count2 = rel_hdr2 ? NUM_SHDR_ENTRIES (rel_hdr2) : 0; 1519 1520 /* PR 17512: file: 0b4f81b7. */ 1521 if (asect->reloc_count != reloc_count + reloc_count2) 1522 return FALSE; 1523 BFD_ASSERT ((rel_hdr && asect->rel_filepos == rel_hdr->sh_offset) 1524 || (rel_hdr2 && asect->rel_filepos == rel_hdr2->sh_offset)); 1525 1526 } 1527 else 1528 { 1529 /* Note that ASECT->RELOC_COUNT tends not to be accurate in this 1530 case because relocations against this section may use the 1531 dynamic symbol table, and in that case bfd_section_from_shdr 1532 in elf.c does not update the RELOC_COUNT. */ 1533 if (asect->size == 0) 1534 return TRUE; 1535 1536 rel_hdr = &d->this_hdr; 1537 reloc_count = NUM_SHDR_ENTRIES (rel_hdr); 1538 rel_hdr2 = NULL; 1539 reloc_count2 = 0; 1540 } 1541 1542 amt = (reloc_count + reloc_count2) * sizeof (arelent); 1543 relents = (arelent *) bfd_alloc (abfd, amt); 1544 if (relents == NULL) 1545 return FALSE; 1546 1547 if (rel_hdr 1548 && !elf_slurp_reloc_table_from_section (abfd, asect, 1549 rel_hdr, reloc_count, 1550 relents, 1551 symbols, dynamic)) 1552 return FALSE; 1553 1554 if (rel_hdr2 1555 && !elf_slurp_reloc_table_from_section (abfd, asect, 1556 rel_hdr2, reloc_count2, 1557 relents + reloc_count, 1558 symbols, dynamic)) 1559 return FALSE; 1560 1561 asect->relocation = relents; 1562 return TRUE; 1563 } 1564 1565 #if DEBUG & 2 1566 static void 1567 elf_debug_section (int num, Elf_Internal_Shdr *hdr) 1568 { 1569 fprintf (stderr, "\nSection#%d '%s' 0x%.8lx\n", num, 1570 hdr->bfd_section != NULL ? hdr->bfd_section->name : "", 1571 (long) hdr); 1572 fprintf (stderr, 1573 "sh_name = %ld\tsh_type = %ld\tsh_flags = %ld\n", 1574 (long) hdr->sh_name, 1575 (long) hdr->sh_type, 1576 (long) hdr->sh_flags); 1577 fprintf (stderr, 1578 "sh_addr = %ld\tsh_offset = %ld\tsh_size = %ld\n", 1579 (long) hdr->sh_addr, 1580 (long) hdr->sh_offset, 1581 (long) hdr->sh_size); 1582 fprintf (stderr, 1583 "sh_link = %ld\tsh_info = %ld\tsh_addralign = %ld\n", 1584 (long) hdr->sh_link, 1585 (long) hdr->sh_info, 1586 (long) hdr->sh_addralign); 1587 fprintf (stderr, "sh_entsize = %ld\n", 1588 (long) hdr->sh_entsize); 1589 fflush (stderr); 1590 } 1591 #endif 1592 1593 #if DEBUG & 1 1594 static void 1595 elf_debug_file (Elf_Internal_Ehdr *ehdrp) 1596 { 1597 fprintf (stderr, "e_entry = 0x%.8lx\n", (long) ehdrp->e_entry); 1598 fprintf (stderr, "e_phoff = %ld\n", (long) ehdrp->e_phoff); 1599 fprintf (stderr, "e_phnum = %ld\n", (long) ehdrp->e_phnum); 1600 fprintf (stderr, "e_phentsize = %ld\n", (long) ehdrp->e_phentsize); 1601 fprintf (stderr, "e_shoff = %ld\n", (long) ehdrp->e_shoff); 1602 fprintf (stderr, "e_shnum = %ld\n", (long) ehdrp->e_shnum); 1603 fprintf (stderr, "e_shentsize = %ld\n", (long) ehdrp->e_shentsize); 1604 } 1605 #endif 1606 1607 /* Create a new BFD as if by bfd_openr. Rather than opening a file, 1608 reconstruct an ELF file by reading the segments out of remote 1609 memory based on the ELF file header at EHDR_VMA and the ELF program 1610 headers it points to. If non-zero, SIZE is the known extent of the 1611 object. If not null, *LOADBASEP is filled in with the difference 1612 between the VMAs from which the segments were read, and the VMAs 1613 the file headers (and hence BFD's idea of each section's VMA) put 1614 them at. 1615 1616 The function TARGET_READ_MEMORY is called to copy LEN bytes from 1617 the remote memory at target address VMA into the local buffer at 1618 MYADDR; it should return zero on success or an `errno' code on 1619 failure. TEMPL must be a BFD for a target with the word size and 1620 byte order found in the remote memory. */ 1621 1622 bfd * 1623 NAME(_bfd_elf,bfd_from_remote_memory) 1624 (bfd *templ, 1625 bfd_vma ehdr_vma, 1626 bfd_size_type size, 1627 bfd_vma *loadbasep, 1628 int (*target_read_memory) (bfd_vma, bfd_byte *, bfd_size_type)) 1629 { 1630 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */ 1631 Elf_Internal_Ehdr i_ehdr; /* Elf file header, internal form */ 1632 Elf_External_Phdr *x_phdrs; 1633 Elf_Internal_Phdr *i_phdrs, *last_phdr, *first_phdr; 1634 bfd *nbfd; 1635 struct bfd_in_memory *bim; 1636 bfd_byte *contents; 1637 int err; 1638 unsigned int i; 1639 bfd_vma high_offset; 1640 bfd_vma shdr_end; 1641 bfd_vma loadbase; 1642 1643 /* Read in the ELF header in external format. */ 1644 err = target_read_memory (ehdr_vma, (bfd_byte *) &x_ehdr, sizeof x_ehdr); 1645 if (err) 1646 { 1647 bfd_set_error (bfd_error_system_call); 1648 errno = err; 1649 return NULL; 1650 } 1651 1652 /* Now check to see if we have a valid ELF file, and one that BFD can 1653 make use of. The magic number must match, the address size ('class') 1654 and byte-swapping must match our XVEC entry. */ 1655 1656 if (! elf_file_p (&x_ehdr) 1657 || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT 1658 || x_ehdr.e_ident[EI_CLASS] != ELFCLASS) 1659 { 1660 bfd_set_error (bfd_error_wrong_format); 1661 return NULL; 1662 } 1663 1664 /* Check that file's byte order matches xvec's */ 1665 switch (x_ehdr.e_ident[EI_DATA]) 1666 { 1667 case ELFDATA2MSB: /* Big-endian */ 1668 if (! bfd_header_big_endian (templ)) 1669 { 1670 bfd_set_error (bfd_error_wrong_format); 1671 return NULL; 1672 } 1673 break; 1674 case ELFDATA2LSB: /* Little-endian */ 1675 if (! bfd_header_little_endian (templ)) 1676 { 1677 bfd_set_error (bfd_error_wrong_format); 1678 return NULL; 1679 } 1680 break; 1681 case ELFDATANONE: /* No data encoding specified */ 1682 default: /* Unknown data encoding specified */ 1683 bfd_set_error (bfd_error_wrong_format); 1684 return NULL; 1685 } 1686 1687 elf_swap_ehdr_in (templ, &x_ehdr, &i_ehdr); 1688 1689 /* The file header tells where to find the program headers. 1690 These are what we use to actually choose what to read. */ 1691 1692 if (i_ehdr.e_phentsize != sizeof (Elf_External_Phdr) || i_ehdr.e_phnum == 0) 1693 { 1694 bfd_set_error (bfd_error_wrong_format); 1695 return NULL; 1696 } 1697 1698 x_phdrs = (Elf_External_Phdr *) 1699 bfd_malloc (i_ehdr.e_phnum * (sizeof *x_phdrs + sizeof *i_phdrs)); 1700 if (x_phdrs == NULL) 1701 return NULL; 1702 err = target_read_memory (ehdr_vma + i_ehdr.e_phoff, (bfd_byte *) x_phdrs, 1703 i_ehdr.e_phnum * sizeof x_phdrs[0]); 1704 if (err) 1705 { 1706 free (x_phdrs); 1707 bfd_set_error (bfd_error_system_call); 1708 errno = err; 1709 return NULL; 1710 } 1711 i_phdrs = (Elf_Internal_Phdr *) &x_phdrs[i_ehdr.e_phnum]; 1712 1713 high_offset = 0; 1714 loadbase = 0; 1715 first_phdr = NULL; 1716 last_phdr = NULL; 1717 for (i = 0; i < i_ehdr.e_phnum; ++i) 1718 { 1719 elf_swap_phdr_in (templ, &x_phdrs[i], &i_phdrs[i]); 1720 if (i_phdrs[i].p_type == PT_LOAD) 1721 { 1722 bfd_vma segment_end = i_phdrs[i].p_offset + i_phdrs[i].p_filesz; 1723 1724 if (segment_end > high_offset) 1725 { 1726 high_offset = segment_end; 1727 last_phdr = &i_phdrs[i]; 1728 } 1729 1730 /* If this program header covers offset zero, where the file 1731 header sits, then we can figure out the loadbase. */ 1732 if (first_phdr == NULL) 1733 { 1734 bfd_vma p_offset = i_phdrs[i].p_offset; 1735 bfd_vma p_vaddr = i_phdrs[i].p_vaddr; 1736 1737 if (i_phdrs[i].p_align > 1) 1738 { 1739 p_offset &= -i_phdrs[i].p_align; 1740 p_vaddr &= -i_phdrs[i].p_align; 1741 } 1742 if (p_offset == 0) 1743 { 1744 loadbase = ehdr_vma - p_vaddr; 1745 first_phdr = &i_phdrs[i]; 1746 } 1747 } 1748 } 1749 } 1750 if (high_offset == 0) 1751 { 1752 /* There were no PT_LOAD segments, so we don't have anything to read. */ 1753 free (x_phdrs); 1754 bfd_set_error (bfd_error_wrong_format); 1755 return NULL; 1756 } 1757 1758 shdr_end = 0; 1759 if (i_ehdr.e_shoff != 0 && i_ehdr.e_shnum != 0 && i_ehdr.e_shentsize != 0) 1760 { 1761 shdr_end = i_ehdr.e_shoff + i_ehdr.e_shnum * i_ehdr.e_shentsize; 1762 1763 if (last_phdr->p_filesz != last_phdr->p_memsz) 1764 { 1765 /* If the last PT_LOAD header has a bss area then ld.so will 1766 have cleared anything past p_filesz, zapping the section 1767 headers. */ 1768 } 1769 else if (size >= shdr_end) 1770 high_offset = size; 1771 else 1772 { 1773 bfd_vma page_size = get_elf_backend_data (templ)->minpagesize; 1774 bfd_vma segment_end = last_phdr->p_offset + last_phdr->p_filesz; 1775 1776 /* Assume we loaded full pages, allowing us to sometimes see 1777 section headers. */ 1778 if (page_size > 1 && shdr_end > segment_end) 1779 { 1780 bfd_vma page_end = (segment_end + page_size - 1) & -page_size; 1781 1782 if (page_end >= shdr_end) 1783 /* Whee, section headers covered. */ 1784 high_offset = shdr_end; 1785 } 1786 } 1787 } 1788 1789 /* Now we know the size of the whole image we want read in. */ 1790 contents = (bfd_byte *) bfd_zmalloc (high_offset); 1791 if (contents == NULL) 1792 { 1793 free (x_phdrs); 1794 return NULL; 1795 } 1796 1797 for (i = 0; i < i_ehdr.e_phnum; ++i) 1798 if (i_phdrs[i].p_type == PT_LOAD) 1799 { 1800 bfd_vma start = i_phdrs[i].p_offset; 1801 bfd_vma end = start + i_phdrs[i].p_filesz; 1802 bfd_vma vaddr = i_phdrs[i].p_vaddr; 1803 1804 /* Extend the beginning of the first pt_load to cover file 1805 header and program headers, if we proved earlier that its 1806 aligned offset is 0. */ 1807 if (first_phdr == &i_phdrs[i]) 1808 { 1809 vaddr -= start; 1810 start = 0; 1811 } 1812 /* Extend the end of the last pt_load to cover section headers. */ 1813 if (last_phdr == &i_phdrs[i]) 1814 end = high_offset; 1815 err = target_read_memory (loadbase + vaddr, 1816 contents + start, end - start); 1817 if (err) 1818 { 1819 free (x_phdrs); 1820 free (contents); 1821 bfd_set_error (bfd_error_system_call); 1822 errno = err; 1823 return NULL; 1824 } 1825 } 1826 free (x_phdrs); 1827 1828 /* If the segments visible in memory didn't include the section headers, 1829 then clear them from the file header. */ 1830 if (high_offset < shdr_end) 1831 { 1832 memset (&x_ehdr.e_shoff, 0, sizeof x_ehdr.e_shoff); 1833 memset (&x_ehdr.e_shnum, 0, sizeof x_ehdr.e_shnum); 1834 memset (&x_ehdr.e_shstrndx, 0, sizeof x_ehdr.e_shstrndx); 1835 } 1836 1837 /* This will normally have been in the first PT_LOAD segment. But it 1838 conceivably could be missing, and we might have just changed it. */ 1839 memcpy (contents, &x_ehdr, sizeof x_ehdr); 1840 1841 /* Now we have a memory image of the ELF file contents. Make a BFD. */ 1842 bim = (struct bfd_in_memory *) bfd_malloc (sizeof (struct bfd_in_memory)); 1843 if (bim == NULL) 1844 { 1845 free (contents); 1846 return NULL; 1847 } 1848 nbfd = _bfd_new_bfd (); 1849 if (nbfd == NULL) 1850 { 1851 free (bim); 1852 free (contents); 1853 return NULL; 1854 } 1855 nbfd->filename = xstrdup ("<in-memory>"); 1856 nbfd->xvec = templ->xvec; 1857 bim->size = high_offset; 1858 bim->buffer = contents; 1859 nbfd->iostream = bim; 1860 nbfd->flags = BFD_IN_MEMORY; 1861 nbfd->iovec = &_bfd_memory_iovec; 1862 nbfd->origin = 0; 1863 nbfd->direction = read_direction; 1864 nbfd->mtime = time (NULL); 1865 nbfd->mtime_set = TRUE; 1866 1867 if (loadbasep) 1868 *loadbasep = loadbase; 1869 return nbfd; 1870 } 1871 1872 /* Function for ELF_R_INFO. */ 1873 1874 bfd_vma 1875 NAME(elf,r_info) (bfd_vma sym, bfd_vma type) 1876 { 1877 return ELF_R_INFO (sym, type); 1878 } 1879 1880 /* Function for ELF_R_SYM. */ 1881 1882 bfd_vma 1883 NAME(elf,r_sym) (bfd_vma r_info) 1884 { 1885 return ELF_R_SYM (r_info); 1886 } 1887 1888 #include "elfcore.h" 1889 1890 /* Size-dependent data and functions. */ 1891 const struct elf_size_info NAME(_bfd_elf,size_info) = { 1892 sizeof (Elf_External_Ehdr), 1893 sizeof (Elf_External_Phdr), 1894 sizeof (Elf_External_Shdr), 1895 sizeof (Elf_External_Rel), 1896 sizeof (Elf_External_Rela), 1897 sizeof (Elf_External_Sym), 1898 sizeof (Elf_External_Dyn), 1899 sizeof (Elf_External_Note), 1900 4, 1901 1, 1902 ARCH_SIZE, LOG_FILE_ALIGN, 1903 ELFCLASS, EV_CURRENT, 1904 elf_write_out_phdrs, 1905 elf_write_shdrs_and_ehdr, 1906 elf_checksum_contents, 1907 elf_write_relocs, 1908 elf_swap_symbol_in, 1909 elf_swap_symbol_out, 1910 elf_slurp_reloc_table, 1911 elf_slurp_symbol_table, 1912 elf_swap_dyn_in, 1913 elf_swap_dyn_out, 1914 elf_swap_reloc_in, 1915 elf_swap_reloc_out, 1916 elf_swap_reloca_in, 1917 elf_swap_reloca_out 1918 }; 1919