PR22746, crash when running 32-bit objdump on corrupted file
[deliverable/binutils-gdb.git] / bfd / elfcode.h
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 \f
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 \f
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: %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 = (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 \f
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 \f
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 \f
1888 #include "elfcore.h"
1889 \f
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 };
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