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) * (bfd_size_type) 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: %pB 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 = (bfd_size_type) 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 (_("%pB: version count (%" PRId64 ")" 1200 " does not match symbol count (%ld)"), 1201 abfd, 1202 (int64_t) (verhdr->sh_size / sizeof (Elf_External_Versym)), 1203 symcount); 1204 1205 /* Slurp in the symbols without the version information, 1206 since that is more helpful than just quitting. */ 1207 verhdr = NULL; 1208 } 1209 1210 if (verhdr != NULL) 1211 { 1212 if (bfd_seek (abfd, verhdr->sh_offset, SEEK_SET) != 0) 1213 goto error_return; 1214 1215 xverbuf = (Elf_External_Versym *) bfd_malloc (verhdr->sh_size); 1216 if (xverbuf == NULL && verhdr->sh_size != 0) 1217 goto error_return; 1218 1219 if (bfd_bread (xverbuf, verhdr->sh_size, abfd) != verhdr->sh_size) 1220 goto error_return; 1221 } 1222 1223 /* Skip first symbol, which is a null dummy. */ 1224 xver = xverbuf; 1225 if (xver != NULL) 1226 ++xver; 1227 isymend = isymbuf + symcount; 1228 for (isym = isymbuf + 1, sym = symbase; isym < isymend; isym++, sym++) 1229 { 1230 memcpy (&sym->internal_elf_sym, isym, sizeof (Elf_Internal_Sym)); 1231 1232 sym->symbol.the_bfd = abfd; 1233 sym->symbol.name = bfd_elf_sym_name (abfd, hdr, isym, NULL); 1234 sym->symbol.value = isym->st_value; 1235 1236 if (isym->st_shndx == SHN_UNDEF) 1237 { 1238 sym->symbol.section = bfd_und_section_ptr; 1239 } 1240 else if (isym->st_shndx == SHN_ABS) 1241 { 1242 sym->symbol.section = bfd_abs_section_ptr; 1243 } 1244 else if (isym->st_shndx == SHN_COMMON) 1245 { 1246 sym->symbol.section = bfd_com_section_ptr; 1247 if ((abfd->flags & BFD_PLUGIN) != 0) 1248 { 1249 asection *xc = bfd_get_section_by_name (abfd, "COMMON"); 1250 1251 if (xc == NULL) 1252 { 1253 flagword flags = (SEC_ALLOC | SEC_IS_COMMON | SEC_KEEP 1254 | SEC_EXCLUDE); 1255 xc = bfd_make_section_with_flags (abfd, "COMMON", flags); 1256 if (xc == NULL) 1257 goto error_return; 1258 } 1259 sym->symbol.section = xc; 1260 } 1261 /* Elf puts the alignment into the `value' field, and 1262 the size into the `size' field. BFD wants to see the 1263 size in the value field, and doesn't care (at the 1264 moment) about the alignment. */ 1265 sym->symbol.value = isym->st_size; 1266 } 1267 else 1268 { 1269 sym->symbol.section 1270 = bfd_section_from_elf_index (abfd, isym->st_shndx); 1271 if (sym->symbol.section == NULL) 1272 { 1273 /* This symbol is in a section for which we did not 1274 create a BFD section. Just use bfd_abs_section, 1275 although it is wrong. FIXME. */ 1276 sym->symbol.section = bfd_abs_section_ptr; 1277 } 1278 } 1279 1280 /* If this is a relocatable file, then the symbol value is 1281 already section relative. */ 1282 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0) 1283 sym->symbol.value -= sym->symbol.section->vma; 1284 1285 switch (ELF_ST_BIND (isym->st_info)) 1286 { 1287 case STB_LOCAL: 1288 sym->symbol.flags |= BSF_LOCAL; 1289 break; 1290 case STB_GLOBAL: 1291 if (isym->st_shndx != SHN_UNDEF && isym->st_shndx != SHN_COMMON) 1292 sym->symbol.flags |= BSF_GLOBAL; 1293 break; 1294 case STB_WEAK: 1295 sym->symbol.flags |= BSF_WEAK; 1296 break; 1297 case STB_GNU_UNIQUE: 1298 sym->symbol.flags |= BSF_GNU_UNIQUE; 1299 break; 1300 } 1301 1302 switch (ELF_ST_TYPE (isym->st_info)) 1303 { 1304 case STT_SECTION: 1305 sym->symbol.flags |= BSF_SECTION_SYM | BSF_DEBUGGING; 1306 break; 1307 case STT_FILE: 1308 sym->symbol.flags |= BSF_FILE | BSF_DEBUGGING; 1309 break; 1310 case STT_FUNC: 1311 sym->symbol.flags |= BSF_FUNCTION; 1312 break; 1313 case STT_COMMON: 1314 /* FIXME: Do we have to put the size field into the value field 1315 as we do with symbols in SHN_COMMON sections (see above) ? */ 1316 sym->symbol.flags |= BSF_ELF_COMMON; 1317 /* Fall through. */ 1318 case STT_OBJECT: 1319 sym->symbol.flags |= BSF_OBJECT; 1320 break; 1321 case STT_TLS: 1322 sym->symbol.flags |= BSF_THREAD_LOCAL; 1323 break; 1324 case STT_RELC: 1325 sym->symbol.flags |= BSF_RELC; 1326 break; 1327 case STT_SRELC: 1328 sym->symbol.flags |= BSF_SRELC; 1329 break; 1330 case STT_GNU_IFUNC: 1331 sym->symbol.flags |= BSF_GNU_INDIRECT_FUNCTION; 1332 break; 1333 } 1334 1335 if (dynamic) 1336 sym->symbol.flags |= BSF_DYNAMIC; 1337 1338 if (xver != NULL) 1339 { 1340 Elf_Internal_Versym iversym; 1341 1342 _bfd_elf_swap_versym_in (abfd, xver, &iversym); 1343 sym->version = iversym.vs_vers; 1344 xver++; 1345 } 1346 1347 /* Do some backend-specific processing on this symbol. */ 1348 if (ebd->elf_backend_symbol_processing) 1349 (*ebd->elf_backend_symbol_processing) (abfd, &sym->symbol); 1350 } 1351 } 1352 1353 /* Do some backend-specific processing on this symbol table. */ 1354 if (ebd->elf_backend_symbol_table_processing) 1355 (*ebd->elf_backend_symbol_table_processing) (abfd, symbase, symcount); 1356 1357 /* We rely on the zalloc to clear out the final symbol entry. */ 1358 1359 symcount = sym - symbase; 1360 1361 /* Fill in the user's symbol pointer vector if needed. */ 1362 if (symptrs) 1363 { 1364 long l = symcount; 1365 1366 sym = symbase; 1367 while (l-- > 0) 1368 { 1369 *symptrs++ = &sym->symbol; 1370 sym++; 1371 } 1372 *symptrs = 0; /* Final null pointer */ 1373 } 1374 1375 if (xverbuf != NULL) 1376 free (xverbuf); 1377 if (isymbuf != NULL && hdr->contents != (unsigned char *) isymbuf) 1378 free (isymbuf); 1379 return symcount; 1380 1381 error_return: 1382 if (xverbuf != NULL) 1383 free (xverbuf); 1384 if (isymbuf != NULL && hdr->contents != (unsigned char *) isymbuf) 1385 free (isymbuf); 1386 return -1; 1387 } 1388 1389 /* Read relocations for ASECT from REL_HDR. There are RELOC_COUNT of 1390 them. */ 1391 1392 static bfd_boolean 1393 elf_slurp_reloc_table_from_section (bfd *abfd, 1394 asection *asect, 1395 Elf_Internal_Shdr *rel_hdr, 1396 bfd_size_type reloc_count, 1397 arelent *relents, 1398 asymbol **symbols, 1399 bfd_boolean dynamic) 1400 { 1401 const struct elf_backend_data * const ebd = get_elf_backend_data (abfd); 1402 void *allocated = NULL; 1403 bfd_byte *native_relocs; 1404 arelent *relent; 1405 unsigned int i; 1406 int entsize; 1407 unsigned int symcount; 1408 1409 allocated = bfd_malloc (rel_hdr->sh_size); 1410 if (allocated == NULL) 1411 goto error_return; 1412 1413 if (bfd_seek (abfd, rel_hdr->sh_offset, SEEK_SET) != 0 1414 || (bfd_bread (allocated, rel_hdr->sh_size, abfd) 1415 != rel_hdr->sh_size)) 1416 goto error_return; 1417 1418 native_relocs = (bfd_byte *) allocated; 1419 1420 entsize = rel_hdr->sh_entsize; 1421 BFD_ASSERT (entsize == sizeof (Elf_External_Rel) 1422 || entsize == sizeof (Elf_External_Rela)); 1423 1424 if (dynamic) 1425 symcount = bfd_get_dynamic_symcount (abfd); 1426 else 1427 symcount = bfd_get_symcount (abfd); 1428 1429 for (i = 0, relent = relents; 1430 i < reloc_count; 1431 i++, relent++, native_relocs += entsize) 1432 { 1433 bfd_boolean res; 1434 Elf_Internal_Rela rela; 1435 1436 if (entsize == sizeof (Elf_External_Rela)) 1437 elf_swap_reloca_in (abfd, native_relocs, &rela); 1438 else 1439 elf_swap_reloc_in (abfd, native_relocs, &rela); 1440 1441 /* The address of an ELF reloc is section relative for an object 1442 file, and absolute for an executable file or shared library. 1443 The address of a normal BFD reloc is always section relative, 1444 and the address of a dynamic reloc is absolute.. */ 1445 if ((abfd->flags & (EXEC_P | DYNAMIC)) == 0 || dynamic) 1446 relent->address = rela.r_offset; 1447 else 1448 relent->address = rela.r_offset - asect->vma; 1449 1450 if (ELF_R_SYM (rela.r_info) == STN_UNDEF) 1451 /* FIXME: This and the error case below mean that we have a 1452 symbol on relocs that is not elf_symbol_type. */ 1453 relent->sym_ptr_ptr = bfd_abs_section_ptr->symbol_ptr_ptr; 1454 else if (ELF_R_SYM (rela.r_info) > symcount) 1455 { 1456 _bfd_error_handler 1457 /* xgettext:c-format */ 1458 (_("%pB(%pA): relocation %d has invalid symbol index %ld"), 1459 abfd, asect, i, (long) ELF_R_SYM (rela.r_info)); 1460 bfd_set_error (bfd_error_bad_value); 1461 relent->sym_ptr_ptr = bfd_abs_section_ptr->symbol_ptr_ptr; 1462 } 1463 else 1464 { 1465 asymbol **ps; 1466 1467 ps = symbols + ELF_R_SYM (rela.r_info) - 1; 1468 1469 relent->sym_ptr_ptr = ps; 1470 } 1471 1472 relent->addend = rela.r_addend; 1473 1474 if ((entsize == sizeof (Elf_External_Rela) 1475 && ebd->elf_info_to_howto != NULL) 1476 || ebd->elf_info_to_howto_rel == NULL) 1477 res = ebd->elf_info_to_howto (abfd, relent, &rela); 1478 else 1479 res = ebd->elf_info_to_howto_rel (abfd, relent, &rela); 1480 1481 if (! res || relent->howto == NULL) 1482 goto error_return; 1483 } 1484 1485 if (allocated != NULL) 1486 free (allocated); 1487 return TRUE; 1488 1489 error_return: 1490 if (allocated != NULL) 1491 free (allocated); 1492 return FALSE; 1493 } 1494 1495 /* Read in and swap the external relocs. */ 1496 1497 bfd_boolean 1498 elf_slurp_reloc_table (bfd *abfd, 1499 asection *asect, 1500 asymbol **symbols, 1501 bfd_boolean dynamic) 1502 { 1503 struct bfd_elf_section_data * const d = elf_section_data (asect); 1504 Elf_Internal_Shdr *rel_hdr; 1505 Elf_Internal_Shdr *rel_hdr2; 1506 bfd_size_type reloc_count; 1507 bfd_size_type reloc_count2; 1508 arelent *relents; 1509 bfd_size_type amt; 1510 1511 if (asect->relocation != NULL) 1512 return TRUE; 1513 1514 if (! dynamic) 1515 { 1516 if ((asect->flags & SEC_RELOC) == 0 1517 || asect->reloc_count == 0) 1518 return TRUE; 1519 1520 rel_hdr = d->rel.hdr; 1521 reloc_count = rel_hdr ? NUM_SHDR_ENTRIES (rel_hdr) : 0; 1522 rel_hdr2 = d->rela.hdr; 1523 reloc_count2 = rel_hdr2 ? NUM_SHDR_ENTRIES (rel_hdr2) : 0; 1524 1525 /* PR 17512: file: 0b4f81b7. */ 1526 if (asect->reloc_count != reloc_count + reloc_count2) 1527 return FALSE; 1528 BFD_ASSERT ((rel_hdr && asect->rel_filepos == rel_hdr->sh_offset) 1529 || (rel_hdr2 && asect->rel_filepos == rel_hdr2->sh_offset)); 1530 1531 } 1532 else 1533 { 1534 /* Note that ASECT->RELOC_COUNT tends not to be accurate in this 1535 case because relocations against this section may use the 1536 dynamic symbol table, and in that case bfd_section_from_shdr 1537 in elf.c does not update the RELOC_COUNT. */ 1538 if (asect->size == 0) 1539 return TRUE; 1540 1541 rel_hdr = &d->this_hdr; 1542 reloc_count = NUM_SHDR_ENTRIES (rel_hdr); 1543 rel_hdr2 = NULL; 1544 reloc_count2 = 0; 1545 } 1546 1547 amt = (reloc_count + reloc_count2) * sizeof (arelent); 1548 relents = (arelent *) bfd_alloc (abfd, amt); 1549 if (relents == NULL) 1550 return FALSE; 1551 1552 if (rel_hdr 1553 && !elf_slurp_reloc_table_from_section (abfd, asect, 1554 rel_hdr, reloc_count, 1555 relents, 1556 symbols, dynamic)) 1557 return FALSE; 1558 1559 if (rel_hdr2 1560 && !elf_slurp_reloc_table_from_section (abfd, asect, 1561 rel_hdr2, reloc_count2, 1562 relents + reloc_count, 1563 symbols, dynamic)) 1564 return FALSE; 1565 1566 asect->relocation = relents; 1567 return TRUE; 1568 } 1569 1570 #if DEBUG & 2 1571 static void 1572 elf_debug_section (int num, Elf_Internal_Shdr *hdr) 1573 { 1574 fprintf (stderr, "\nSection#%d '%s' 0x%.8lx\n", num, 1575 hdr->bfd_section != NULL ? hdr->bfd_section->name : "", 1576 (long) hdr); 1577 fprintf (stderr, 1578 "sh_name = %ld\tsh_type = %ld\tsh_flags = %ld\n", 1579 (long) hdr->sh_name, 1580 (long) hdr->sh_type, 1581 (long) hdr->sh_flags); 1582 fprintf (stderr, 1583 "sh_addr = %ld\tsh_offset = %ld\tsh_size = %ld\n", 1584 (long) hdr->sh_addr, 1585 (long) hdr->sh_offset, 1586 (long) hdr->sh_size); 1587 fprintf (stderr, 1588 "sh_link = %ld\tsh_info = %ld\tsh_addralign = %ld\n", 1589 (long) hdr->sh_link, 1590 (long) hdr->sh_info, 1591 (long) hdr->sh_addralign); 1592 fprintf (stderr, "sh_entsize = %ld\n", 1593 (long) hdr->sh_entsize); 1594 fflush (stderr); 1595 } 1596 #endif 1597 1598 #if DEBUG & 1 1599 static void 1600 elf_debug_file (Elf_Internal_Ehdr *ehdrp) 1601 { 1602 fprintf (stderr, "e_entry = 0x%.8lx\n", (long) ehdrp->e_entry); 1603 fprintf (stderr, "e_phoff = %ld\n", (long) ehdrp->e_phoff); 1604 fprintf (stderr, "e_phnum = %ld\n", (long) ehdrp->e_phnum); 1605 fprintf (stderr, "e_phentsize = %ld\n", (long) ehdrp->e_phentsize); 1606 fprintf (stderr, "e_shoff = %ld\n", (long) ehdrp->e_shoff); 1607 fprintf (stderr, "e_shnum = %ld\n", (long) ehdrp->e_shnum); 1608 fprintf (stderr, "e_shentsize = %ld\n", (long) ehdrp->e_shentsize); 1609 } 1610 #endif 1611 1612 /* Create a new BFD as if by bfd_openr. Rather than opening a file, 1613 reconstruct an ELF file by reading the segments out of remote 1614 memory based on the ELF file header at EHDR_VMA and the ELF program 1615 headers it points to. If non-zero, SIZE is the known extent of the 1616 object. If not null, *LOADBASEP is filled in with the difference 1617 between the VMAs from which the segments were read, and the VMAs 1618 the file headers (and hence BFD's idea of each section's VMA) put 1619 them at. 1620 1621 The function TARGET_READ_MEMORY is called to copy LEN bytes from 1622 the remote memory at target address VMA into the local buffer at 1623 MYADDR; it should return zero on success or an `errno' code on 1624 failure. TEMPL must be a BFD for a target with the word size and 1625 byte order found in the remote memory. */ 1626 1627 bfd * 1628 NAME(_bfd_elf,bfd_from_remote_memory) 1629 (bfd *templ, 1630 bfd_vma ehdr_vma, 1631 bfd_size_type size, 1632 bfd_vma *loadbasep, 1633 int (*target_read_memory) (bfd_vma, bfd_byte *, bfd_size_type)) 1634 { 1635 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */ 1636 Elf_Internal_Ehdr i_ehdr; /* Elf file header, internal form */ 1637 Elf_External_Phdr *x_phdrs; 1638 Elf_Internal_Phdr *i_phdrs, *last_phdr, *first_phdr; 1639 bfd *nbfd; 1640 struct bfd_in_memory *bim; 1641 bfd_byte *contents; 1642 int err; 1643 unsigned int i; 1644 bfd_vma high_offset; 1645 bfd_vma shdr_end; 1646 bfd_vma loadbase; 1647 1648 /* Read in the ELF header in external format. */ 1649 err = target_read_memory (ehdr_vma, (bfd_byte *) &x_ehdr, sizeof x_ehdr); 1650 if (err) 1651 { 1652 bfd_set_error (bfd_error_system_call); 1653 errno = err; 1654 return NULL; 1655 } 1656 1657 /* Now check to see if we have a valid ELF file, and one that BFD can 1658 make use of. The magic number must match, the address size ('class') 1659 and byte-swapping must match our XVEC entry. */ 1660 1661 if (! elf_file_p (&x_ehdr) 1662 || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT 1663 || x_ehdr.e_ident[EI_CLASS] != ELFCLASS) 1664 { 1665 bfd_set_error (bfd_error_wrong_format); 1666 return NULL; 1667 } 1668 1669 /* Check that file's byte order matches xvec's */ 1670 switch (x_ehdr.e_ident[EI_DATA]) 1671 { 1672 case ELFDATA2MSB: /* Big-endian */ 1673 if (! bfd_header_big_endian (templ)) 1674 { 1675 bfd_set_error (bfd_error_wrong_format); 1676 return NULL; 1677 } 1678 break; 1679 case ELFDATA2LSB: /* Little-endian */ 1680 if (! bfd_header_little_endian (templ)) 1681 { 1682 bfd_set_error (bfd_error_wrong_format); 1683 return NULL; 1684 } 1685 break; 1686 case ELFDATANONE: /* No data encoding specified */ 1687 default: /* Unknown data encoding specified */ 1688 bfd_set_error (bfd_error_wrong_format); 1689 return NULL; 1690 } 1691 1692 elf_swap_ehdr_in (templ, &x_ehdr, &i_ehdr); 1693 1694 /* The file header tells where to find the program headers. 1695 These are what we use to actually choose what to read. */ 1696 1697 if (i_ehdr.e_phentsize != sizeof (Elf_External_Phdr) || i_ehdr.e_phnum == 0) 1698 { 1699 bfd_set_error (bfd_error_wrong_format); 1700 return NULL; 1701 } 1702 1703 x_phdrs = (Elf_External_Phdr *) 1704 bfd_malloc (i_ehdr.e_phnum * (sizeof *x_phdrs + sizeof *i_phdrs)); 1705 if (x_phdrs == NULL) 1706 return NULL; 1707 err = target_read_memory (ehdr_vma + i_ehdr.e_phoff, (bfd_byte *) x_phdrs, 1708 i_ehdr.e_phnum * sizeof x_phdrs[0]); 1709 if (err) 1710 { 1711 free (x_phdrs); 1712 bfd_set_error (bfd_error_system_call); 1713 errno = err; 1714 return NULL; 1715 } 1716 i_phdrs = (Elf_Internal_Phdr *) &x_phdrs[i_ehdr.e_phnum]; 1717 1718 high_offset = 0; 1719 loadbase = 0; 1720 first_phdr = NULL; 1721 last_phdr = NULL; 1722 for (i = 0; i < i_ehdr.e_phnum; ++i) 1723 { 1724 elf_swap_phdr_in (templ, &x_phdrs[i], &i_phdrs[i]); 1725 if (i_phdrs[i].p_type == PT_LOAD) 1726 { 1727 bfd_vma segment_end = i_phdrs[i].p_offset + i_phdrs[i].p_filesz; 1728 1729 if (segment_end > high_offset) 1730 { 1731 high_offset = segment_end; 1732 last_phdr = &i_phdrs[i]; 1733 } 1734 1735 /* If this program header covers offset zero, where the file 1736 header sits, then we can figure out the loadbase. */ 1737 if (first_phdr == NULL) 1738 { 1739 bfd_vma p_offset = i_phdrs[i].p_offset; 1740 bfd_vma p_vaddr = i_phdrs[i].p_vaddr; 1741 1742 if (i_phdrs[i].p_align > 1) 1743 { 1744 p_offset &= -i_phdrs[i].p_align; 1745 p_vaddr &= -i_phdrs[i].p_align; 1746 } 1747 if (p_offset == 0) 1748 { 1749 loadbase = ehdr_vma - p_vaddr; 1750 first_phdr = &i_phdrs[i]; 1751 } 1752 } 1753 } 1754 } 1755 if (high_offset == 0) 1756 { 1757 /* There were no PT_LOAD segments, so we don't have anything to read. */ 1758 free (x_phdrs); 1759 bfd_set_error (bfd_error_wrong_format); 1760 return NULL; 1761 } 1762 1763 shdr_end = 0; 1764 if (i_ehdr.e_shoff != 0 && i_ehdr.e_shnum != 0 && i_ehdr.e_shentsize != 0) 1765 { 1766 shdr_end = i_ehdr.e_shoff + i_ehdr.e_shnum * i_ehdr.e_shentsize; 1767 1768 if (last_phdr->p_filesz != last_phdr->p_memsz) 1769 { 1770 /* If the last PT_LOAD header has a bss area then ld.so will 1771 have cleared anything past p_filesz, zapping the section 1772 headers. */ 1773 } 1774 else if (size >= shdr_end) 1775 high_offset = size; 1776 else 1777 { 1778 bfd_vma page_size = get_elf_backend_data (templ)->minpagesize; 1779 bfd_vma segment_end = last_phdr->p_offset + last_phdr->p_filesz; 1780 1781 /* Assume we loaded full pages, allowing us to sometimes see 1782 section headers. */ 1783 if (page_size > 1 && shdr_end > segment_end) 1784 { 1785 bfd_vma page_end = (segment_end + page_size - 1) & -page_size; 1786 1787 if (page_end >= shdr_end) 1788 /* Whee, section headers covered. */ 1789 high_offset = shdr_end; 1790 } 1791 } 1792 } 1793 1794 /* Now we know the size of the whole image we want read in. */ 1795 contents = (bfd_byte *) bfd_zmalloc (high_offset); 1796 if (contents == NULL) 1797 { 1798 free (x_phdrs); 1799 return NULL; 1800 } 1801 1802 for (i = 0; i < i_ehdr.e_phnum; ++i) 1803 if (i_phdrs[i].p_type == PT_LOAD) 1804 { 1805 bfd_vma start = i_phdrs[i].p_offset; 1806 bfd_vma end = start + i_phdrs[i].p_filesz; 1807 bfd_vma vaddr = i_phdrs[i].p_vaddr; 1808 1809 /* Extend the beginning of the first pt_load to cover file 1810 header and program headers, if we proved earlier that its 1811 aligned offset is 0. */ 1812 if (first_phdr == &i_phdrs[i]) 1813 { 1814 vaddr -= start; 1815 start = 0; 1816 } 1817 /* Extend the end of the last pt_load to cover section headers. */ 1818 if (last_phdr == &i_phdrs[i]) 1819 end = high_offset; 1820 err = target_read_memory (loadbase + vaddr, 1821 contents + start, end - start); 1822 if (err) 1823 { 1824 free (x_phdrs); 1825 free (contents); 1826 bfd_set_error (bfd_error_system_call); 1827 errno = err; 1828 return NULL; 1829 } 1830 } 1831 free (x_phdrs); 1832 1833 /* If the segments visible in memory didn't include the section headers, 1834 then clear them from the file header. */ 1835 if (high_offset < shdr_end) 1836 { 1837 memset (&x_ehdr.e_shoff, 0, sizeof x_ehdr.e_shoff); 1838 memset (&x_ehdr.e_shnum, 0, sizeof x_ehdr.e_shnum); 1839 memset (&x_ehdr.e_shstrndx, 0, sizeof x_ehdr.e_shstrndx); 1840 } 1841 1842 /* This will normally have been in the first PT_LOAD segment. But it 1843 conceivably could be missing, and we might have just changed it. */ 1844 memcpy (contents, &x_ehdr, sizeof x_ehdr); 1845 1846 /* Now we have a memory image of the ELF file contents. Make a BFD. */ 1847 bim = (struct bfd_in_memory *) bfd_malloc (sizeof (struct bfd_in_memory)); 1848 if (bim == NULL) 1849 { 1850 free (contents); 1851 return NULL; 1852 } 1853 nbfd = _bfd_new_bfd (); 1854 if (nbfd == NULL) 1855 { 1856 free (bim); 1857 free (contents); 1858 return NULL; 1859 } 1860 nbfd->filename = xstrdup ("<in-memory>"); 1861 nbfd->xvec = templ->xvec; 1862 bim->size = high_offset; 1863 bim->buffer = contents; 1864 nbfd->iostream = bim; 1865 nbfd->flags = BFD_IN_MEMORY; 1866 nbfd->iovec = &_bfd_memory_iovec; 1867 nbfd->origin = 0; 1868 nbfd->direction = read_direction; 1869 nbfd->mtime = time (NULL); 1870 nbfd->mtime_set = TRUE; 1871 1872 if (loadbasep) 1873 *loadbasep = loadbase; 1874 return nbfd; 1875 } 1876 1877 /* Function for ELF_R_INFO. */ 1878 1879 bfd_vma 1880 NAME(elf,r_info) (bfd_vma sym, bfd_vma type) 1881 { 1882 return ELF_R_INFO (sym, type); 1883 } 1884 1885 /* Function for ELF_R_SYM. */ 1886 1887 bfd_vma 1888 NAME(elf,r_sym) (bfd_vma r_info) 1889 { 1890 return ELF_R_SYM (r_info); 1891 } 1892 1893 #include "elfcore.h" 1894 1895 /* Size-dependent data and functions. */ 1896 const struct elf_size_info NAME(_bfd_elf,size_info) = { 1897 sizeof (Elf_External_Ehdr), 1898 sizeof (Elf_External_Phdr), 1899 sizeof (Elf_External_Shdr), 1900 sizeof (Elf_External_Rel), 1901 sizeof (Elf_External_Rela), 1902 sizeof (Elf_External_Sym), 1903 sizeof (Elf_External_Dyn), 1904 sizeof (Elf_External_Note), 1905 4, 1906 1, 1907 ARCH_SIZE, LOG_FILE_ALIGN, 1908 ELFCLASS, EV_CURRENT, 1909 elf_write_out_phdrs, 1910 elf_write_shdrs_and_ehdr, 1911 elf_checksum_contents, 1912 elf_write_relocs, 1913 elf_swap_symbol_in, 1914 elf_swap_symbol_out, 1915 elf_slurp_reloc_table, 1916 elf_slurp_symbol_table, 1917 elf_swap_dyn_in, 1918 elf_swap_dyn_out, 1919 elf_swap_reloc_in, 1920 elf_swap_reloc_out, 1921 elf_swap_reloca_in, 1922 elf_swap_reloca_out 1923 }; 1924