]> git.ipfire.org Git - thirdparty/binutils-gdb.git/blob - bfd/elfxx-x86.c
x86: Add _bfd_x86_elf_size_dynamic_sections
[thirdparty/binutils-gdb.git] / bfd / elfxx-x86.c
1 /* x86 specific support for ELF
2 Copyright (C) 2017 Free Software Foundation, Inc.
3
4 This file is part of BFD, the Binary File Descriptor library.
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
19 MA 02110-1301, USA. */
20
21 #include "elfxx-x86.h"
22 #include "elf-vxworks.h"
23 #include "objalloc.h"
24 #include "elf/i386.h"
25 #include "elf/x86-64.h"
26
27 /* The name of the dynamic interpreter. This is put in the .interp
28 section. */
29
30 #define ELF32_DYNAMIC_INTERPRETER "/usr/lib/libc.so.1"
31 #define ELF64_DYNAMIC_INTERPRETER "/lib/ld64.so.1"
32 #define ELFX32_DYNAMIC_INTERPRETER "/lib/ldx32.so.1"
33
34 bfd_boolean
35 _bfd_x86_elf_mkobject (bfd *abfd)
36 {
37 return bfd_elf_allocate_object (abfd,
38 sizeof (struct elf_x86_obj_tdata),
39 get_elf_backend_data (abfd)->target_id);
40 }
41
42 /* _TLS_MODULE_BASE_ needs to be treated especially when linking
43 executables. Rather than setting it to the beginning of the TLS
44 section, we have to set it to the end. This function may be called
45 multiple times, it is idempotent. */
46
47 void
48 _bfd_x86_elf_set_tls_module_base (struct bfd_link_info *info)
49 {
50 struct elf_x86_link_hash_table *htab;
51 struct bfd_link_hash_entry *base;
52 const struct elf_backend_data *bed;
53
54 if (!bfd_link_executable (info))
55 return;
56
57 bed = get_elf_backend_data (info->output_bfd);
58 htab = elf_x86_hash_table (info, bed->target_id);
59 if (htab == NULL)
60 return;
61
62 base = htab->tls_module_base;
63 if (base == NULL)
64 return;
65
66 base->u.def.value = htab->elf.tls_size;
67 }
68
69 /* Return the base VMA address which should be subtracted from real addresses
70 when resolving @dtpoff relocation.
71 This is PT_TLS segment p_vaddr. */
72
73 bfd_vma
74 _bfd_x86_elf_dtpoff_base (struct bfd_link_info *info)
75 {
76 /* If tls_sec is NULL, we should have signalled an error already. */
77 if (elf_hash_table (info)->tls_sec == NULL)
78 return 0;
79 return elf_hash_table (info)->tls_sec->vma;
80 }
81
82 /* Allocate space in .plt, .got and associated reloc sections for
83 dynamic relocs. */
84
85 static bfd_boolean
86 elf_x86_allocate_dynrelocs (struct elf_link_hash_entry *h,
87 void *inf)
88 {
89 struct bfd_link_info *info;
90 struct elf_x86_link_hash_table *htab;
91 struct elf_x86_link_hash_entry *eh;
92 struct elf_dyn_relocs *p;
93 unsigned int plt_entry_size;
94 bfd_boolean resolved_to_zero;
95 const struct elf_backend_data *bed;
96
97 if (h->root.type == bfd_link_hash_indirect)
98 return TRUE;
99
100 eh = (struct elf_x86_link_hash_entry *) h;
101
102 info = (struct bfd_link_info *) inf;
103 bed = get_elf_backend_data (info->output_bfd);
104 htab = elf_x86_hash_table (info, bed->target_id);
105 if (htab == NULL)
106 return FALSE;
107
108 plt_entry_size = htab->plt.plt_entry_size;
109
110 resolved_to_zero = UNDEFINED_WEAK_RESOLVED_TO_ZERO (info,
111 bed->target_id,
112 eh->has_got_reloc,
113 eh);
114
115 /* Clear the reference count of function pointer relocations if
116 symbol isn't a normal function. */
117 if (h->type != STT_FUNC)
118 eh->func_pointer_refcount = 0;
119
120 /* We can't use the GOT PLT if pointer equality is needed since
121 finish_dynamic_symbol won't clear symbol value and the dynamic
122 linker won't update the GOT slot. We will get into an infinite
123 loop at run-time. */
124 if (htab->plt_got != NULL
125 && h->type != STT_GNU_IFUNC
126 && !h->pointer_equality_needed
127 && h->plt.refcount > 0
128 && h->got.refcount > 0)
129 {
130 /* Don't use the regular PLT if there are both GOT and GOTPLT
131 reloctions. */
132 h->plt.offset = (bfd_vma) -1;
133
134 /* Use the GOT PLT. */
135 eh->plt_got.refcount = 1;
136 }
137
138 /* Since STT_GNU_IFUNC symbol must go through PLT, we handle it
139 here if it is defined and referenced in a non-shared object. */
140 if (h->type == STT_GNU_IFUNC
141 && h->def_regular)
142 {
143 if (_bfd_elf_allocate_ifunc_dyn_relocs (info, h, &eh->dyn_relocs,
144 &htab->readonly_dynrelocs_against_ifunc,
145 plt_entry_size,
146 (htab->plt.has_plt0
147 * plt_entry_size),
148 htab->got_entry_size,
149 TRUE))
150 {
151 asection *s = htab->plt_second;
152 if (h->plt.offset != (bfd_vma) -1 && s != NULL)
153 {
154 /* Use the second PLT section if it is created. */
155 eh->plt_second.offset = s->size;
156
157 /* Make room for this entry in the second PLT section. */
158 s->size += htab->non_lazy_plt->plt_entry_size;
159 }
160
161 return TRUE;
162 }
163 else
164 return FALSE;
165 }
166 /* Don't create the PLT entry if there are only function pointer
167 relocations which can be resolved at run-time. */
168 else if (htab->elf.dynamic_sections_created
169 && (h->plt.refcount > eh->func_pointer_refcount
170 || eh->plt_got.refcount > 0))
171 {
172 bfd_boolean use_plt_got = eh->plt_got.refcount > 0;
173
174 /* Clear the reference count of function pointer relocations
175 if PLT is used. */
176 eh->func_pointer_refcount = 0;
177
178 /* Make sure this symbol is output as a dynamic symbol.
179 Undefined weak syms won't yet be marked as dynamic. */
180 if (h->dynindx == -1
181 && !h->forced_local
182 && !resolved_to_zero
183 && h->root.type == bfd_link_hash_undefweak)
184 {
185 if (! bfd_elf_link_record_dynamic_symbol (info, h))
186 return FALSE;
187 }
188
189 if (bfd_link_pic (info)
190 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h))
191 {
192 asection *s = htab->elf.splt;
193 asection *second_s = htab->plt_second;
194 asection *got_s = htab->plt_got;
195
196 /* If this is the first .plt entry, make room for the special
197 first entry. The .plt section is used by prelink to undo
198 prelinking for dynamic relocations. */
199 if (s->size == 0)
200 s->size = htab->plt.has_plt0 * plt_entry_size;
201
202 if (use_plt_got)
203 eh->plt_got.offset = got_s->size;
204 else
205 {
206 h->plt.offset = s->size;
207 if (second_s)
208 eh->plt_second.offset = second_s->size;
209 }
210
211 /* If this symbol is not defined in a regular file, and we are
212 not generating a shared library, then set the symbol to this
213 location in the .plt. This is required to make function
214 pointers compare as equal between the normal executable and
215 the shared library. */
216 if (! bfd_link_pic (info)
217 && !h->def_regular)
218 {
219 if (use_plt_got)
220 {
221 /* We need to make a call to the entry of the GOT PLT
222 instead of regular PLT entry. */
223 h->root.u.def.section = got_s;
224 h->root.u.def.value = eh->plt_got.offset;
225 }
226 else
227 {
228 if (second_s)
229 {
230 /* We need to make a call to the entry of the
231 second PLT instead of regular PLT entry. */
232 h->root.u.def.section = second_s;
233 h->root.u.def.value = eh->plt_second.offset;
234 }
235 else
236 {
237 h->root.u.def.section = s;
238 h->root.u.def.value = h->plt.offset;
239 }
240 }
241 }
242
243 /* Make room for this entry. */
244 if (use_plt_got)
245 got_s->size += htab->non_lazy_plt->plt_entry_size;
246 else
247 {
248 s->size += plt_entry_size;
249 if (second_s)
250 second_s->size += htab->non_lazy_plt->plt_entry_size;
251
252 /* We also need to make an entry in the .got.plt section,
253 which will be placed in the .got section by the linker
254 script. */
255 htab->elf.sgotplt->size += htab->got_entry_size;
256
257 /* There should be no PLT relocation against resolved
258 undefined weak symbol in executable. */
259 if (!resolved_to_zero)
260 {
261 /* We also need to make an entry in the .rel.plt
262 section. */
263 htab->elf.srelplt->size += htab->sizeof_reloc;
264 htab->elf.srelplt->reloc_count++;
265 }
266 }
267
268 if (htab->is_vxworks && !bfd_link_pic (info))
269 {
270 /* VxWorks has a second set of relocations for each PLT entry
271 in executables. They go in a separate relocation section,
272 which is processed by the kernel loader. */
273
274 /* There are two relocations for the initial PLT entry: an
275 R_386_32 relocation for _GLOBAL_OFFSET_TABLE_ + 4 and an
276 R_386_32 relocation for _GLOBAL_OFFSET_TABLE_ + 8. */
277
278 asection *srelplt2 = htab->srelplt2;
279 if (h->plt.offset == plt_entry_size)
280 srelplt2->size += (htab->sizeof_reloc * 2);
281
282 /* There are two extra relocations for each subsequent PLT entry:
283 an R_386_32 relocation for the GOT entry, and an R_386_32
284 relocation for the PLT entry. */
285
286 srelplt2->size += (htab->sizeof_reloc * 2);
287 }
288 }
289 else
290 {
291 eh->plt_got.offset = (bfd_vma) -1;
292 h->plt.offset = (bfd_vma) -1;
293 h->needs_plt = 0;
294 }
295 }
296 else
297 {
298 eh->plt_got.offset = (bfd_vma) -1;
299 h->plt.offset = (bfd_vma) -1;
300 h->needs_plt = 0;
301 }
302
303 eh->tlsdesc_got = (bfd_vma) -1;
304
305 /* For i386, if R_386_TLS_{IE_32,IE,GOTIE} symbol is now local to the
306 binary, make it a R_386_TLS_LE_32 requiring no TLS entry. For
307 x86-64, if R_X86_64_GOTTPOFF symbol is now local to the binary,
308 make it a R_X86_64_TPOFF32 requiring no GOT entry. */
309 if (h->got.refcount > 0
310 && bfd_link_executable (info)
311 && h->dynindx == -1
312 && (elf_x86_hash_entry (h)->tls_type & GOT_TLS_IE))
313 h->got.offset = (bfd_vma) -1;
314 else if (h->got.refcount > 0)
315 {
316 asection *s;
317 bfd_boolean dyn;
318 int tls_type = elf_x86_hash_entry (h)->tls_type;
319
320 /* Make sure this symbol is output as a dynamic symbol.
321 Undefined weak syms won't yet be marked as dynamic. */
322 if (h->dynindx == -1
323 && !h->forced_local
324 && !resolved_to_zero
325 && h->root.type == bfd_link_hash_undefweak)
326 {
327 if (! bfd_elf_link_record_dynamic_symbol (info, h))
328 return FALSE;
329 }
330
331 s = htab->elf.sgot;
332 if (GOT_TLS_GDESC_P (tls_type))
333 {
334 eh->tlsdesc_got = htab->elf.sgotplt->size
335 - elf_x86_compute_jump_table_size (htab);
336 htab->elf.sgotplt->size += 2 * htab->got_entry_size;
337 h->got.offset = (bfd_vma) -2;
338 }
339 if (! GOT_TLS_GDESC_P (tls_type)
340 || GOT_TLS_GD_P (tls_type))
341 {
342 h->got.offset = s->size;
343 s->size += htab->got_entry_size;
344 /* R_386_TLS_GD and R_X86_64_TLSGD need 2 consecutive GOT
345 slots. */
346 if (GOT_TLS_GD_P (tls_type) || tls_type == GOT_TLS_IE_BOTH)
347 s->size += htab->got_entry_size;
348 }
349 dyn = htab->elf.dynamic_sections_created;
350 /* R_386_TLS_IE_32 needs one dynamic relocation,
351 R_386_TLS_IE resp. R_386_TLS_GOTIE needs one dynamic relocation,
352 (but if both R_386_TLS_IE_32 and R_386_TLS_IE is present, we
353 need two), R_386_TLS_GD and R_X86_64_TLSGD need one if local
354 symbol and two if global. No dynamic relocation against
355 resolved undefined weak symbol in executable. */
356 if (tls_type == GOT_TLS_IE_BOTH)
357 htab->elf.srelgot->size += 2 * htab->sizeof_reloc;
358 else if ((GOT_TLS_GD_P (tls_type) && h->dynindx == -1)
359 || (tls_type & GOT_TLS_IE))
360 htab->elf.srelgot->size += htab->sizeof_reloc;
361 else if (GOT_TLS_GD_P (tls_type))
362 htab->elf.srelgot->size += 2 * htab->sizeof_reloc;
363 else if (! GOT_TLS_GDESC_P (tls_type)
364 && ((ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
365 && !resolved_to_zero)
366 || h->root.type != bfd_link_hash_undefweak)
367 && (bfd_link_pic (info)
368 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h)))
369 htab->elf.srelgot->size += htab->sizeof_reloc;
370 if (GOT_TLS_GDESC_P (tls_type))
371 htab->elf.srelplt->size += htab->sizeof_reloc;
372 }
373 else
374 h->got.offset = (bfd_vma) -1;
375
376 if (eh->dyn_relocs == NULL)
377 return TRUE;
378
379 /* In the shared -Bsymbolic case, discard space allocated for
380 dynamic pc-relative relocs against symbols which turn out to be
381 defined in regular objects. For the normal shared case, discard
382 space for pc-relative relocs that have become local due to symbol
383 visibility changes. */
384
385 if (bfd_link_pic (info))
386 {
387 /* Relocs that use pc_count are those that appear on a call
388 insn, or certain REL relocs that can generated via assembly.
389 We want calls to protected symbols to resolve directly to the
390 function rather than going via the plt. If people want
391 function pointer comparisons to work as expected then they
392 should avoid writing weird assembly. */
393 if (SYMBOL_CALLS_LOCAL (info, h))
394 {
395 struct elf_dyn_relocs **pp;
396
397 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
398 {
399 p->count -= p->pc_count;
400 p->pc_count = 0;
401 if (p->count == 0)
402 *pp = p->next;
403 else
404 pp = &p->next;
405 }
406 }
407
408 if (htab->is_vxworks)
409 {
410 struct elf_dyn_relocs **pp;
411 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
412 {
413 if (strcmp (p->sec->output_section->name, ".tls_vars") == 0)
414 *pp = p->next;
415 else
416 pp = &p->next;
417 }
418 }
419
420 /* Also discard relocs on undefined weak syms with non-default
421 visibility or in PIE. */
422 if (eh->dyn_relocs != NULL)
423 {
424 if (h->root.type == bfd_link_hash_undefweak)
425 {
426 /* Undefined weak symbol is never bound locally in shared
427 library. */
428 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
429 || resolved_to_zero)
430 {
431 if (bed->target_id == I386_ELF_DATA
432 && h->non_got_ref)
433 {
434 /* Keep dynamic non-GOT/non-PLT relocation so
435 that we can branch to 0 without PLT. */
436 struct elf_dyn_relocs **pp;
437
438 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
439 if (p->pc_count == 0)
440 *pp = p->next;
441 else
442 {
443 /* Remove non-R_386_PC32 relocation. */
444 p->count = p->pc_count;
445 pp = &p->next;
446 }
447
448 /* Make sure undefined weak symbols are output
449 as dynamic symbols in PIEs for dynamic non-GOT
450 non-PLT reloations. */
451 if (eh->dyn_relocs != NULL
452 && !bfd_elf_link_record_dynamic_symbol (info, h))
453 return FALSE;
454 }
455 else
456 eh->dyn_relocs = NULL;
457 }
458 else if (h->dynindx == -1
459 && !h->forced_local
460 && !bfd_elf_link_record_dynamic_symbol (info, h))
461 return FALSE;
462 }
463 else if (bfd_link_executable (info)
464 && (h->needs_copy || eh->needs_copy)
465 && h->def_dynamic
466 && !h->def_regular)
467 {
468 /* NB: needs_copy is set only for x86-64. For PIE,
469 discard space for pc-relative relocs against symbols
470 which turn out to need copy relocs. */
471 struct elf_dyn_relocs **pp;
472
473 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
474 {
475 if (p->pc_count != 0)
476 *pp = p->next;
477 else
478 pp = &p->next;
479 }
480 }
481 }
482 }
483 else if (ELIMINATE_COPY_RELOCS)
484 {
485 /* For the non-shared case, discard space for relocs against
486 symbols which turn out to need copy relocs or are not
487 dynamic. Keep dynamic relocations for run-time function
488 pointer initialization. */
489
490 if ((!h->non_got_ref
491 || eh->func_pointer_refcount > 0
492 || (h->root.type == bfd_link_hash_undefweak
493 && !resolved_to_zero))
494 && ((h->def_dynamic
495 && !h->def_regular)
496 || (htab->elf.dynamic_sections_created
497 && (h->root.type == bfd_link_hash_undefweak
498 || h->root.type == bfd_link_hash_undefined))))
499 {
500 /* Make sure this symbol is output as a dynamic symbol.
501 Undefined weak syms won't yet be marked as dynamic. */
502 if (h->dynindx == -1
503 && !h->forced_local
504 && !resolved_to_zero
505 && h->root.type == bfd_link_hash_undefweak
506 && ! bfd_elf_link_record_dynamic_symbol (info, h))
507 return FALSE;
508
509 /* If that succeeded, we know we'll be keeping all the
510 relocs. */
511 if (h->dynindx != -1)
512 goto keep;
513 }
514
515 eh->dyn_relocs = NULL;
516 eh->func_pointer_refcount = 0;
517
518 keep: ;
519 }
520
521 /* Finally, allocate space. */
522 for (p = eh->dyn_relocs; p != NULL; p = p->next)
523 {
524 asection *sreloc;
525
526 sreloc = elf_section_data (p->sec)->sreloc;
527
528 BFD_ASSERT (sreloc != NULL);
529 sreloc->size += p->count * htab->sizeof_reloc;
530 }
531
532 return TRUE;
533 }
534
535 /* Find any dynamic relocs that apply to read-only sections. */
536
537 bfd_boolean
538 _bfd_x86_elf_readonly_dynrelocs (struct elf_link_hash_entry *h,
539 void *inf)
540 {
541 struct elf_x86_link_hash_entry *eh;
542 struct elf_dyn_relocs *p;
543
544 /* Skip local IFUNC symbols. */
545 if (h->forced_local && h->type == STT_GNU_IFUNC)
546 return TRUE;
547
548 eh = (struct elf_x86_link_hash_entry *) h;
549 for (p = eh->dyn_relocs; p != NULL; p = p->next)
550 {
551 asection *s = p->sec->output_section;
552
553 if (s != NULL && (s->flags & SEC_READONLY) != 0)
554 {
555 struct bfd_link_info *info = (struct bfd_link_info *) inf;
556
557 info->flags |= DF_TEXTREL;
558
559 if ((info->warn_shared_textrel && bfd_link_pic (info))
560 || info->error_textrel)
561 /* xgettext:c-format */
562 info->callbacks->einfo (_("%P: %B: warning: relocation against `%s' in readonly section `%A'\n"),
563 p->sec->owner, h->root.root.string,
564 p->sec);
565
566 /* Not an error, just cut short the traversal. */
567 return FALSE;
568 }
569 }
570 return TRUE;
571 }
572
573 /* Allocate space in .plt, .got and associated reloc sections for
574 local dynamic relocs. */
575
576 static bfd_boolean
577 elf_x86_allocate_local_dynreloc (void **slot, void *inf)
578 {
579 struct elf_link_hash_entry *h
580 = (struct elf_link_hash_entry *) *slot;
581
582 if (h->type != STT_GNU_IFUNC
583 || !h->def_regular
584 || !h->ref_regular
585 || !h->forced_local
586 || h->root.type != bfd_link_hash_defined)
587 abort ();
588
589 return elf_x86_allocate_dynrelocs (h, inf);
590 }
591
592 /* Find and/or create a hash entry for local symbol. */
593
594 struct elf_link_hash_entry *
595 _bfd_elf_x86_get_local_sym_hash (struct elf_x86_link_hash_table *htab,
596 bfd *abfd, const Elf_Internal_Rela *rel,
597 bfd_boolean create)
598 {
599 struct elf_x86_link_hash_entry e, *ret;
600 asection *sec = abfd->sections;
601 hashval_t h = ELF_LOCAL_SYMBOL_HASH (sec->id,
602 htab->r_sym (rel->r_info));
603 void **slot;
604
605 e.elf.indx = sec->id;
606 e.elf.dynstr_index = htab->r_sym (rel->r_info);
607 slot = htab_find_slot_with_hash (htab->loc_hash_table, &e, h,
608 create ? INSERT : NO_INSERT);
609
610 if (!slot)
611 return NULL;
612
613 if (*slot)
614 {
615 ret = (struct elf_x86_link_hash_entry *) *slot;
616 return &ret->elf;
617 }
618
619 ret = (struct elf_x86_link_hash_entry *)
620 objalloc_alloc ((struct objalloc *) htab->loc_hash_memory,
621 sizeof (struct elf_x86_link_hash_entry));
622 if (ret)
623 {
624 memset (ret, 0, sizeof (*ret));
625 ret->elf.indx = sec->id;
626 ret->elf.dynstr_index = htab->r_sym (rel->r_info);
627 ret->elf.dynindx = -1;
628 ret->plt_got.offset = (bfd_vma) -1;
629 *slot = ret;
630 }
631 return &ret->elf;
632 }
633
634 /* Create an entry in a x86 ELF linker hash table. NB: THIS MUST BE IN
635 SYNC WITH _bfd_elf_link_hash_newfunc. */
636
637 struct bfd_hash_entry *
638 _bfd_x86_elf_link_hash_newfunc (struct bfd_hash_entry *entry,
639 struct bfd_hash_table *table,
640 const char *string)
641 {
642 /* Allocate the structure if it has not already been allocated by a
643 subclass. */
644 if (entry == NULL)
645 {
646 entry = (struct bfd_hash_entry *)
647 bfd_hash_allocate (table,
648 sizeof (struct elf_x86_link_hash_entry));
649 if (entry == NULL)
650 return entry;
651 }
652
653 /* Call the allocation method of the superclass. */
654 entry = _bfd_link_hash_newfunc (entry, table, string);
655 if (entry != NULL)
656 {
657 struct elf_x86_link_hash_entry *eh
658 = (struct elf_x86_link_hash_entry *) entry;
659 struct elf_link_hash_table *htab
660 = (struct elf_link_hash_table *) table;
661
662 memset (&eh->elf.size, 0,
663 (sizeof (struct elf_x86_link_hash_entry)
664 - offsetof (struct elf_link_hash_entry, size)));
665 /* Set local fields. */
666 eh->elf.indx = -1;
667 eh->elf.dynindx = -1;
668 eh->elf.got = htab->init_got_refcount;
669 eh->elf.plt = htab->init_plt_refcount;
670 /* Assume that we have been called by a non-ELF symbol reader.
671 This flag is then reset by the code which reads an ELF input
672 file. This ensures that a symbol created by a non-ELF symbol
673 reader will have the flag set correctly. */
674 eh->elf.non_elf = 1;
675 eh->plt_second.offset = (bfd_vma) -1;
676 eh->plt_got.offset = (bfd_vma) -1;
677 eh->tlsdesc_got = (bfd_vma) -1;
678 }
679
680 return entry;
681 }
682
683 /* Compute a hash of a local hash entry. We use elf_link_hash_entry
684 for local symbol so that we can handle local STT_GNU_IFUNC symbols
685 as global symbol. We reuse indx and dynstr_index for local symbol
686 hash since they aren't used by global symbols in this backend. */
687
688 hashval_t
689 _bfd_x86_elf_local_htab_hash (const void *ptr)
690 {
691 struct elf_link_hash_entry *h
692 = (struct elf_link_hash_entry *) ptr;
693 return ELF_LOCAL_SYMBOL_HASH (h->indx, h->dynstr_index);
694 }
695
696 /* Compare local hash entries. */
697
698 int
699 _bfd_x86_elf_local_htab_eq (const void *ptr1, const void *ptr2)
700 {
701 struct elf_link_hash_entry *h1
702 = (struct elf_link_hash_entry *) ptr1;
703 struct elf_link_hash_entry *h2
704 = (struct elf_link_hash_entry *) ptr2;
705
706 return h1->indx == h2->indx && h1->dynstr_index == h2->dynstr_index;
707 }
708
709 /* Destroy an x86 ELF linker hash table. */
710
711 static void
712 elf_x86_link_hash_table_free (bfd *obfd)
713 {
714 struct elf_x86_link_hash_table *htab
715 = (struct elf_x86_link_hash_table *) obfd->link.hash;
716
717 if (htab->loc_hash_table)
718 htab_delete (htab->loc_hash_table);
719 if (htab->loc_hash_memory)
720 objalloc_free ((struct objalloc *) htab->loc_hash_memory);
721 _bfd_elf_link_hash_table_free (obfd);
722 }
723
724 static bfd_boolean
725 elf_i386_is_reloc_section (const char *secname)
726 {
727 return CONST_STRNEQ (secname, ".rel");
728 }
729
730 #ifdef BFD64
731 static bfd_boolean
732 elf_x86_64_is_reloc_section (const char *secname)
733 {
734 return CONST_STRNEQ (secname, ".rela");
735 }
736 #endif
737
738 /* Create an x86 ELF linker hash table. */
739
740 struct bfd_link_hash_table *
741 _bfd_x86_elf_link_hash_table_create (bfd *abfd)
742 {
743 struct elf_x86_link_hash_table *ret;
744 const struct elf_backend_data *bed;
745 bfd_size_type amt = sizeof (struct elf_x86_link_hash_table);
746
747 ret = (struct elf_x86_link_hash_table *) bfd_zmalloc (amt);
748 if (ret == NULL)
749 return NULL;
750
751 bed = get_elf_backend_data (abfd);
752 if (!_bfd_elf_link_hash_table_init (&ret->elf, abfd,
753 _bfd_x86_elf_link_hash_newfunc,
754 sizeof (struct elf_x86_link_hash_entry),
755 bed->target_id))
756 {
757 free (ret);
758 return NULL;
759 }
760
761 #ifdef BFD64
762 /* NB: If BFD64 isn't defined, only i386 will be supported. */
763 if (bed->target_id == X86_64_ELF_DATA)
764 {
765 ret->convert_load = _bfd_x86_64_elf_convert_load;
766 ret->is_reloc_section = elf_x86_64_is_reloc_section;
767 ret->dt_reloc = DT_RELA;
768 ret->dt_reloc_sz = DT_RELASZ;
769 ret->dt_reloc_ent = DT_RELAENT;
770 ret->got_entry_size = 8;
771 }
772 if (ABI_64_P (abfd))
773 {
774 ret->r_info = elf64_r_info;
775 ret->r_sym = elf64_r_sym;
776 ret->sizeof_reloc = sizeof (Elf64_External_Rela);
777 ret->pointer_r_type = R_X86_64_64;
778 ret->dynamic_interpreter = ELF64_DYNAMIC_INTERPRETER;
779 ret->dynamic_interpreter_size = sizeof ELF64_DYNAMIC_INTERPRETER;
780 ret->tls_get_addr = "__tls_get_addr";
781 }
782 else
783 #endif
784 {
785 ret->r_info = elf32_r_info;
786 ret->r_sym = elf32_r_sym;
787 if (bed->target_id == X86_64_ELF_DATA)
788 {
789 ret->sizeof_reloc = sizeof (Elf32_External_Rela);
790 ret->pointer_r_type = R_X86_64_32;
791 ret->dynamic_interpreter = ELFX32_DYNAMIC_INTERPRETER;
792 ret->dynamic_interpreter_size
793 = sizeof ELFX32_DYNAMIC_INTERPRETER;
794 ret->tls_get_addr = "__tls_get_addr";
795 }
796 else
797 {
798 ret->convert_load = _bfd_i386_elf_convert_load;
799 ret->is_reloc_section = elf_i386_is_reloc_section;
800 ret->dt_reloc = DT_REL;
801 ret->dt_reloc_sz = DT_RELSZ;
802 ret->dt_reloc_ent = DT_RELENT;
803 ret->sizeof_reloc = sizeof (Elf32_External_Rel);
804 ret->got_entry_size = 4;
805 ret->pointer_r_type = R_386_32;
806 ret->dynamic_interpreter = ELF32_DYNAMIC_INTERPRETER;
807 ret->dynamic_interpreter_size
808 = sizeof ELF32_DYNAMIC_INTERPRETER;
809 ret->tls_get_addr = "___tls_get_addr";
810 }
811 }
812 ret->target_id = bed->target_id;
813
814 ret->loc_hash_table = htab_try_create (1024,
815 _bfd_x86_elf_local_htab_hash,
816 _bfd_x86_elf_local_htab_eq,
817 NULL);
818 ret->loc_hash_memory = objalloc_create ();
819 if (!ret->loc_hash_table || !ret->loc_hash_memory)
820 {
821 elf_x86_link_hash_table_free (abfd);
822 return NULL;
823 }
824 ret->elf.root.hash_table_free = elf_x86_link_hash_table_free;
825
826 return &ret->elf.root;
827 }
828
829 /* Sort relocs into address order. */
830
831 int
832 _bfd_x86_elf_compare_relocs (const void *ap, const void *bp)
833 {
834 const arelent *a = * (const arelent **) ap;
835 const arelent *b = * (const arelent **) bp;
836
837 if (a->address > b->address)
838 return 1;
839 else if (a->address < b->address)
840 return -1;
841 else
842 return 0;
843 }
844
845 bfd_boolean
846 _bfd_x86_elf_link_check_relocs (bfd *abfd, struct bfd_link_info *info)
847 {
848 if (!bfd_link_relocatable (info))
849 {
850 /* Check for __tls_get_addr reference. */
851 struct elf_x86_link_hash_table *htab;
852 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
853 htab = elf_x86_hash_table (info, bed->target_id);
854 if (htab)
855 {
856 struct elf_link_hash_entry *h
857 = elf_link_hash_lookup (elf_hash_table (info),
858 htab->tls_get_addr,
859 FALSE, FALSE, FALSE);
860 if (h != NULL)
861 ((struct elf_x86_link_hash_entry *) h)->tls_get_addr = 1;
862 }
863 }
864
865 /* Invoke the regular ELF backend linker to do all the work. */
866 return _bfd_elf_link_check_relocs (abfd, info);
867 }
868
869 /* Set the sizes of the dynamic sections. */
870
871 bfd_boolean
872 _bfd_x86_elf_size_dynamic_sections (bfd *output_bfd,
873 struct bfd_link_info *info)
874 {
875 struct elf_x86_link_hash_table *htab;
876 bfd *dynobj;
877 asection *s;
878 bfd_boolean relocs;
879 bfd *ibfd;
880 const struct elf_backend_data *bed
881 = get_elf_backend_data (output_bfd);
882
883 htab = elf_x86_hash_table (info, bed->target_id);
884 if (htab == NULL)
885 return FALSE;
886 dynobj = htab->elf.dynobj;
887 if (dynobj == NULL)
888 abort ();
889
890 /* Set up .got offsets for local syms, and space for local dynamic
891 relocs. */
892 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
893 {
894 bfd_signed_vma *local_got;
895 bfd_signed_vma *end_local_got;
896 char *local_tls_type;
897 bfd_vma *local_tlsdesc_gotent;
898 bfd_size_type locsymcount;
899 Elf_Internal_Shdr *symtab_hdr;
900 asection *srel;
901
902 if (! is_x86_elf (ibfd, htab))
903 continue;
904
905 for (s = ibfd->sections; s != NULL; s = s->next)
906 {
907 struct elf_dyn_relocs *p;
908
909 if (!htab->convert_load (ibfd, s, info))
910 return FALSE;
911
912 for (p = ((struct elf_dyn_relocs *)
913 elf_section_data (s)->local_dynrel);
914 p != NULL;
915 p = p->next)
916 {
917 if (!bfd_is_abs_section (p->sec)
918 && bfd_is_abs_section (p->sec->output_section))
919 {
920 /* Input section has been discarded, either because
921 it is a copy of a linkonce section or due to
922 linker script /DISCARD/, so we'll be discarding
923 the relocs too. */
924 }
925 else if (htab->is_vxworks
926 && strcmp (p->sec->output_section->name,
927 ".tls_vars") == 0)
928 {
929 /* Relocations in vxworks .tls_vars sections are
930 handled specially by the loader. */
931 }
932 else if (p->count != 0)
933 {
934 srel = elf_section_data (p->sec)->sreloc;
935 srel->size += p->count * htab->sizeof_reloc;
936 if ((p->sec->output_section->flags & SEC_READONLY) != 0
937 && (info->flags & DF_TEXTREL) == 0)
938 {
939 info->flags |= DF_TEXTREL;
940 if ((info->warn_shared_textrel && bfd_link_pic (info))
941 || info->error_textrel)
942 /* xgettext:c-format */
943 info->callbacks->einfo (_("%P: %B: warning: relocation in readonly section `%A'\n"),
944 p->sec->owner, p->sec);
945 }
946 }
947 }
948 }
949
950 local_got = elf_local_got_refcounts (ibfd);
951 if (!local_got)
952 continue;
953
954 symtab_hdr = &elf_symtab_hdr (ibfd);
955 locsymcount = symtab_hdr->sh_info;
956 end_local_got = local_got + locsymcount;
957 local_tls_type = elf_x86_local_got_tls_type (ibfd);
958 local_tlsdesc_gotent = elf_x86_local_tlsdesc_gotent (ibfd);
959 s = htab->elf.sgot;
960 srel = htab->elf.srelgot;
961 for (; local_got < end_local_got;
962 ++local_got, ++local_tls_type, ++local_tlsdesc_gotent)
963 {
964 *local_tlsdesc_gotent = (bfd_vma) -1;
965 if (*local_got > 0)
966 {
967 if (GOT_TLS_GDESC_P (*local_tls_type))
968 {
969 *local_tlsdesc_gotent = htab->elf.sgotplt->size
970 - elf_x86_compute_jump_table_size (htab);
971 htab->elf.sgotplt->size += 2 * htab->got_entry_size;
972 *local_got = (bfd_vma) -2;
973 }
974 if (! GOT_TLS_GDESC_P (*local_tls_type)
975 || GOT_TLS_GD_P (*local_tls_type))
976 {
977 *local_got = s->size;
978 s->size += htab->got_entry_size;
979 if (GOT_TLS_GD_P (*local_tls_type)
980 || *local_tls_type == GOT_TLS_IE_BOTH)
981 s->size += htab->got_entry_size;
982 }
983 if (bfd_link_pic (info)
984 || GOT_TLS_GD_ANY_P (*local_tls_type)
985 || (*local_tls_type & GOT_TLS_IE))
986 {
987 if (*local_tls_type == GOT_TLS_IE_BOTH)
988 srel->size += 2 * htab->sizeof_reloc;
989 else if (GOT_TLS_GD_P (*local_tls_type)
990 || ! GOT_TLS_GDESC_P (*local_tls_type))
991 srel->size += htab->sizeof_reloc;
992 if (GOT_TLS_GDESC_P (*local_tls_type))
993 {
994 htab->elf.srelplt->size += htab->sizeof_reloc;
995 if (bed->target_id == X86_64_ELF_DATA)
996 htab->tlsdesc_plt = (bfd_vma) -1;
997 }
998 }
999 }
1000 else
1001 *local_got = (bfd_vma) -1;
1002 }
1003 }
1004
1005 if (htab->tls_ld_or_ldm_got.refcount > 0)
1006 {
1007 /* Allocate 2 got entries and 1 dynamic reloc for R_386_TLS_LDM
1008 or R_X86_64_TLSLD relocs. */
1009 htab->tls_ld_or_ldm_got.offset = htab->elf.sgot->size;
1010 htab->elf.sgot->size += 2 * htab->got_entry_size;
1011 htab->elf.srelgot->size += htab->sizeof_reloc;
1012 }
1013 else
1014 htab->tls_ld_or_ldm_got.offset = -1;
1015
1016 /* Allocate global sym .plt and .got entries, and space for global
1017 sym dynamic relocs. */
1018 elf_link_hash_traverse (&htab->elf, elf_x86_allocate_dynrelocs,
1019 info);
1020
1021 /* Allocate .plt and .got entries, and space for local symbols. */
1022 htab_traverse (htab->loc_hash_table, elf_x86_allocate_local_dynreloc,
1023 info);
1024
1025 /* For every jump slot reserved in the sgotplt, reloc_count is
1026 incremented. However, when we reserve space for TLS descriptors,
1027 it's not incremented, so in order to compute the space reserved
1028 for them, it suffices to multiply the reloc count by the jump
1029 slot size.
1030
1031 PR ld/13302: We start next_irelative_index at the end of .rela.plt
1032 so that R_{386,X86_64}_IRELATIVE entries come last. */
1033 if (htab->elf.srelplt)
1034 {
1035 htab->next_tls_desc_index = htab->elf.srelplt->reloc_count;
1036 htab->sgotplt_jump_table_size
1037 = elf_x86_compute_jump_table_size (htab);
1038 htab->next_irelative_index = htab->elf.srelplt->reloc_count - 1;
1039 }
1040 else if (htab->elf.irelplt)
1041 htab->next_irelative_index = htab->elf.irelplt->reloc_count - 1;
1042
1043 if (htab->tlsdesc_plt)
1044 {
1045 /* NB: tlsdesc_plt is set only for x86-64. If we're not using
1046 lazy TLS relocations, don't generate the PLT and GOT entries
1047 they require. */
1048 if ((info->flags & DF_BIND_NOW))
1049 htab->tlsdesc_plt = 0;
1050 else
1051 {
1052 htab->tlsdesc_got = htab->elf.sgot->size;
1053 htab->elf.sgot->size += htab->got_entry_size;
1054 /* Reserve room for the initial entry.
1055 FIXME: we could probably do away with it in this case. */
1056 if (htab->elf.splt->size == 0)
1057 htab->elf.splt->size = htab->plt.plt_entry_size;
1058 htab->tlsdesc_plt = htab->elf.splt->size;
1059 htab->elf.splt->size += htab->plt.plt_entry_size;
1060 }
1061 }
1062
1063 if (htab->elf.sgotplt)
1064 {
1065 /* Don't allocate .got.plt section if there are no GOT nor PLT
1066 entries and there is no reference to _GLOBAL_OFFSET_TABLE_. */
1067 if ((htab->elf.hgot == NULL
1068 || !htab->elf.hgot->ref_regular_nonweak)
1069 && (htab->elf.sgotplt->size == bed->got_header_size)
1070 && (htab->elf.splt == NULL
1071 || htab->elf.splt->size == 0)
1072 && (htab->elf.sgot == NULL
1073 || htab->elf.sgot->size == 0)
1074 && (htab->elf.iplt == NULL
1075 || htab->elf.iplt->size == 0)
1076 && (htab->elf.igotplt == NULL
1077 || htab->elf.igotplt->size == 0))
1078 htab->elf.sgotplt->size = 0;
1079 }
1080
1081 if (_bfd_elf_eh_frame_present (info))
1082 {
1083 if (htab->plt_eh_frame != NULL
1084 && htab->elf.splt != NULL
1085 && htab->elf.splt->size != 0
1086 && !bfd_is_abs_section (htab->elf.splt->output_section))
1087 htab->plt_eh_frame->size = htab->plt.eh_frame_plt_size;
1088
1089 if (htab->plt_got_eh_frame != NULL
1090 && htab->plt_got != NULL
1091 && htab->plt_got->size != 0
1092 && !bfd_is_abs_section (htab->plt_got->output_section))
1093 htab->plt_got_eh_frame->size
1094 = htab->non_lazy_plt->eh_frame_plt_size;
1095
1096 /* Unwind info for the second PLT and .plt.got sections are
1097 identical. */
1098 if (htab->plt_second_eh_frame != NULL
1099 && htab->plt_second != NULL
1100 && htab->plt_second->size != 0
1101 && !bfd_is_abs_section (htab->plt_second->output_section))
1102 htab->plt_second_eh_frame->size
1103 = htab->non_lazy_plt->eh_frame_plt_size;
1104 }
1105
1106 /* We now have determined the sizes of the various dynamic sections.
1107 Allocate memory for them. */
1108 relocs = FALSE;
1109 for (s = dynobj->sections; s != NULL; s = s->next)
1110 {
1111 bfd_boolean strip_section = TRUE;
1112
1113 if ((s->flags & SEC_LINKER_CREATED) == 0)
1114 continue;
1115
1116 if (s == htab->elf.splt
1117 || s == htab->elf.sgot)
1118 {
1119 /* Strip this section if we don't need it; see the
1120 comment below. */
1121 /* We'd like to strip these sections if they aren't needed, but if
1122 we've exported dynamic symbols from them we must leave them.
1123 It's too late to tell BFD to get rid of the symbols. */
1124
1125 if (htab->elf.hplt != NULL)
1126 strip_section = FALSE;
1127 }
1128 else if (s == htab->elf.sgotplt
1129 || s == htab->elf.iplt
1130 || s == htab->elf.igotplt
1131 || s == htab->plt_second
1132 || s == htab->plt_got
1133 || s == htab->plt_eh_frame
1134 || s == htab->plt_got_eh_frame
1135 || s == htab->plt_second_eh_frame
1136 || s == htab->elf.sdynbss
1137 || s == htab->elf.sdynrelro)
1138 {
1139 /* Strip these too. */
1140 }
1141 else if (htab->is_reloc_section (bfd_get_section_name (dynobj, s)))
1142 {
1143 if (s->size != 0
1144 && s != htab->elf.srelplt
1145 && s != htab->srelplt2)
1146 relocs = TRUE;
1147
1148 /* We use the reloc_count field as a counter if we need
1149 to copy relocs into the output file. */
1150 if (s != htab->elf.srelplt)
1151 s->reloc_count = 0;
1152 }
1153 else
1154 {
1155 /* It's not one of our sections, so don't allocate space. */
1156 continue;
1157 }
1158
1159 if (s->size == 0)
1160 {
1161 /* If we don't need this section, strip it from the
1162 output file. This is mostly to handle .rel.bss and
1163 .rel.plt. We must create both sections in
1164 create_dynamic_sections, because they must be created
1165 before the linker maps input sections to output
1166 sections. The linker does that before
1167 adjust_dynamic_symbol is called, and it is that
1168 function which decides whether anything needs to go
1169 into these sections. */
1170 if (strip_section)
1171 s->flags |= SEC_EXCLUDE;
1172 continue;
1173 }
1174
1175 if ((s->flags & SEC_HAS_CONTENTS) == 0)
1176 continue;
1177
1178 /* Allocate memory for the section contents. We use bfd_zalloc
1179 here in case unused entries are not reclaimed before the
1180 section's contents are written out. This should not happen,
1181 but this way if it does, we get a R_386_NONE or R_X86_64_NONE
1182 reloc instead of garbage. */
1183 s->contents = (unsigned char *) bfd_zalloc (dynobj, s->size);
1184 if (s->contents == NULL)
1185 return FALSE;
1186 }
1187
1188 if (htab->plt_eh_frame != NULL
1189 && htab->plt_eh_frame->contents != NULL)
1190 {
1191 memcpy (htab->plt_eh_frame->contents,
1192 htab->plt.eh_frame_plt,
1193 htab->plt_eh_frame->size);
1194 bfd_put_32 (dynobj, htab->elf.splt->size,
1195 htab->plt_eh_frame->contents + PLT_FDE_LEN_OFFSET);
1196 }
1197
1198 if (htab->plt_got_eh_frame != NULL
1199 && htab->plt_got_eh_frame->contents != NULL)
1200 {
1201 memcpy (htab->plt_got_eh_frame->contents,
1202 htab->non_lazy_plt->eh_frame_plt,
1203 htab->plt_got_eh_frame->size);
1204 bfd_put_32 (dynobj, htab->plt_got->size,
1205 (htab->plt_got_eh_frame->contents
1206 + PLT_FDE_LEN_OFFSET));
1207 }
1208
1209 if (htab->plt_second_eh_frame != NULL
1210 && htab->plt_second_eh_frame->contents != NULL)
1211 {
1212 memcpy (htab->plt_second_eh_frame->contents,
1213 htab->non_lazy_plt->eh_frame_plt,
1214 htab->plt_second_eh_frame->size);
1215 bfd_put_32 (dynobj, htab->plt_second->size,
1216 (htab->plt_second_eh_frame->contents
1217 + PLT_FDE_LEN_OFFSET));
1218 }
1219
1220 if (htab->elf.dynamic_sections_created)
1221 {
1222 /* Add some entries to the .dynamic section. We fill in the
1223 values later, in elf_{i386,x86_64}_finish_dynamic_sections,
1224 but we must add the entries now so that we get the correct
1225 size for the .dynamic section. The DT_DEBUG entry is filled
1226 in by the dynamic linker and used by the debugger. */
1227 #define add_dynamic_entry(TAG, VAL) \
1228 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
1229
1230 if (bfd_link_executable (info))
1231 {
1232 if (!add_dynamic_entry (DT_DEBUG, 0))
1233 return FALSE;
1234 }
1235
1236 if (htab->elf.splt->size != 0)
1237 {
1238 /* DT_PLTGOT is used by prelink even if there is no PLT
1239 relocation. */
1240 if (!add_dynamic_entry (DT_PLTGOT, 0))
1241 return FALSE;
1242 }
1243
1244 if (htab->elf.srelplt->size != 0)
1245 {
1246 if (!add_dynamic_entry (DT_PLTRELSZ, 0)
1247 || !add_dynamic_entry (DT_PLTREL, htab->dt_reloc)
1248 || !add_dynamic_entry (DT_JMPREL, 0))
1249 return FALSE;
1250 }
1251
1252 if (htab->tlsdesc_plt
1253 && (!add_dynamic_entry (DT_TLSDESC_PLT, 0)
1254 || !add_dynamic_entry (DT_TLSDESC_GOT, 0)))
1255 return FALSE;
1256
1257 if (relocs)
1258 {
1259 if (!add_dynamic_entry (htab->dt_reloc, 0)
1260 || !add_dynamic_entry (htab->dt_reloc_sz, 0)
1261 || !add_dynamic_entry (htab->dt_reloc_ent,
1262 htab->sizeof_reloc))
1263 return FALSE;
1264
1265 /* If any dynamic relocs apply to a read-only section,
1266 then we need a DT_TEXTREL entry. */
1267 if ((info->flags & DF_TEXTREL) == 0)
1268 elf_link_hash_traverse (&htab->elf,
1269 _bfd_x86_elf_readonly_dynrelocs,
1270 info);
1271
1272 if ((info->flags & DF_TEXTREL) != 0)
1273 {
1274 if (htab->readonly_dynrelocs_against_ifunc)
1275 {
1276 info->callbacks->einfo
1277 (_("%P%X: read-only segment has dynamic IFUNC relocations; recompile with -fPIC\n"));
1278 bfd_set_error (bfd_error_bad_value);
1279 return FALSE;
1280 }
1281
1282 if (!add_dynamic_entry (DT_TEXTREL, 0))
1283 return FALSE;
1284 }
1285 }
1286 if (htab->is_vxworks
1287 && !elf_vxworks_add_dynamic_entries (output_bfd, info))
1288 return FALSE;
1289 }
1290 #undef add_dynamic_entry
1291
1292 return TRUE;
1293 }
1294
1295 bfd_boolean
1296 _bfd_x86_elf_always_size_sections (bfd *output_bfd,
1297 struct bfd_link_info *info)
1298 {
1299 asection *tls_sec = elf_hash_table (info)->tls_sec;
1300
1301 if (tls_sec)
1302 {
1303 struct elf_link_hash_entry *tlsbase;
1304
1305 tlsbase = elf_link_hash_lookup (elf_hash_table (info),
1306 "_TLS_MODULE_BASE_",
1307 FALSE, FALSE, FALSE);
1308
1309 if (tlsbase && tlsbase->type == STT_TLS)
1310 {
1311 struct elf_x86_link_hash_table *htab;
1312 struct bfd_link_hash_entry *bh = NULL;
1313 const struct elf_backend_data *bed
1314 = get_elf_backend_data (output_bfd);
1315
1316 htab = elf_x86_hash_table (info, bed->target_id);
1317 if (htab == NULL)
1318 return FALSE;
1319
1320 if (!(_bfd_generic_link_add_one_symbol
1321 (info, output_bfd, "_TLS_MODULE_BASE_", BSF_LOCAL,
1322 tls_sec, 0, NULL, FALSE,
1323 bed->collect, &bh)))
1324 return FALSE;
1325
1326 htab->tls_module_base = bh;
1327
1328 tlsbase = (struct elf_link_hash_entry *)bh;
1329 tlsbase->def_regular = 1;
1330 tlsbase->other = STV_HIDDEN;
1331 tlsbase->root.linker_def = 1;
1332 (*bed->elf_backend_hide_symbol) (info, tlsbase, TRUE);
1333 }
1334 }
1335
1336 return TRUE;
1337 }
1338
1339 void
1340 _bfd_x86_elf_merge_symbol_attribute (struct elf_link_hash_entry *h,
1341 const Elf_Internal_Sym *isym,
1342 bfd_boolean definition,
1343 bfd_boolean dynamic ATTRIBUTE_UNUSED)
1344 {
1345 if (definition)
1346 {
1347 struct elf_x86_link_hash_entry *eh
1348 = (struct elf_x86_link_hash_entry *) h;
1349 eh->def_protected = (ELF_ST_VISIBILITY (isym->st_other)
1350 == STV_PROTECTED);
1351 }
1352 }
1353
1354 /* Copy the extra info we tack onto an elf_link_hash_entry. */
1355
1356 void
1357 _bfd_x86_elf_copy_indirect_symbol (struct bfd_link_info *info,
1358 struct elf_link_hash_entry *dir,
1359 struct elf_link_hash_entry *ind)
1360 {
1361 struct elf_x86_link_hash_entry *edir, *eind;
1362
1363 edir = (struct elf_x86_link_hash_entry *) dir;
1364 eind = (struct elf_x86_link_hash_entry *) ind;
1365
1366 if (eind->dyn_relocs != NULL)
1367 {
1368 if (edir->dyn_relocs != NULL)
1369 {
1370 struct elf_dyn_relocs **pp;
1371 struct elf_dyn_relocs *p;
1372
1373 /* Add reloc counts against the indirect sym to the direct sym
1374 list. Merge any entries against the same section. */
1375 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
1376 {
1377 struct elf_dyn_relocs *q;
1378
1379 for (q = edir->dyn_relocs; q != NULL; q = q->next)
1380 if (q->sec == p->sec)
1381 {
1382 q->pc_count += p->pc_count;
1383 q->count += p->count;
1384 *pp = p->next;
1385 break;
1386 }
1387 if (q == NULL)
1388 pp = &p->next;
1389 }
1390 *pp = edir->dyn_relocs;
1391 }
1392
1393 edir->dyn_relocs = eind->dyn_relocs;
1394 eind->dyn_relocs = NULL;
1395 }
1396
1397 if (ind->root.type == bfd_link_hash_indirect
1398 && dir->got.refcount <= 0)
1399 {
1400 edir->tls_type = eind->tls_type;
1401 eind->tls_type = GOT_UNKNOWN;
1402 }
1403
1404 /* Copy gotoff_ref so that elf_i386_adjust_dynamic_symbol will
1405 generate a R_386_COPY reloc. */
1406 edir->gotoff_ref |= eind->gotoff_ref;
1407
1408 edir->has_got_reloc |= eind->has_got_reloc;
1409 edir->has_non_got_reloc |= eind->has_non_got_reloc;
1410
1411 if (ELIMINATE_COPY_RELOCS
1412 && ind->root.type != bfd_link_hash_indirect
1413 && dir->dynamic_adjusted)
1414 {
1415 /* If called to transfer flags for a weakdef during processing
1416 of elf_adjust_dynamic_symbol, don't copy non_got_ref.
1417 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
1418 if (dir->versioned != versioned_hidden)
1419 dir->ref_dynamic |= ind->ref_dynamic;
1420 dir->ref_regular |= ind->ref_regular;
1421 dir->ref_regular_nonweak |= ind->ref_regular_nonweak;
1422 dir->needs_plt |= ind->needs_plt;
1423 dir->pointer_equality_needed |= ind->pointer_equality_needed;
1424 }
1425 else
1426 {
1427 if (eind->func_pointer_refcount > 0)
1428 {
1429 edir->func_pointer_refcount += eind->func_pointer_refcount;
1430 eind->func_pointer_refcount = 0;
1431 }
1432
1433 _bfd_elf_link_hash_copy_indirect (info, dir, ind);
1434 }
1435 }
1436
1437 /* Remove undefined weak symbol from the dynamic symbol table if it
1438 is resolved to 0. */
1439
1440 bfd_boolean
1441 _bfd_x86_elf_fixup_symbol (struct bfd_link_info *info,
1442 struct elf_link_hash_entry *h)
1443 {
1444 if (h->dynindx != -1)
1445 {
1446 const struct elf_backend_data *bed
1447 = get_elf_backend_data (info->output_bfd);
1448 if (UNDEFINED_WEAK_RESOLVED_TO_ZERO (info,
1449 bed->target_id,
1450 elf_x86_hash_entry (h)->has_got_reloc,
1451 elf_x86_hash_entry (h)))
1452 {
1453 h->dynindx = -1;
1454 _bfd_elf_strtab_delref (elf_hash_table (info)->dynstr,
1455 h->dynstr_index);
1456 }
1457 }
1458 return TRUE;
1459 }
1460
1461 /* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */
1462
1463 bfd_boolean
1464 _bfd_x86_elf_hash_symbol (struct elf_link_hash_entry *h)
1465 {
1466 if (h->plt.offset != (bfd_vma) -1
1467 && !h->def_regular
1468 && !h->pointer_equality_needed)
1469 return FALSE;
1470
1471 return _bfd_elf_hash_symbol (h);
1472 }
1473
1474 /* Adjust a symbol defined by a dynamic object and referenced by a
1475 regular object. The current definition is in some section of the
1476 dynamic object, but we're not including those sections. We have to
1477 change the definition to something the rest of the link can
1478 understand. */
1479
1480 bfd_boolean
1481 _bfd_x86_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
1482 struct elf_link_hash_entry *h)
1483 {
1484 struct elf_x86_link_hash_table *htab;
1485 asection *s, *srel;
1486 struct elf_x86_link_hash_entry *eh;
1487 struct elf_dyn_relocs *p;
1488 const struct elf_backend_data *bed
1489 = get_elf_backend_data (info->output_bfd);
1490
1491 /* STT_GNU_IFUNC symbol must go through PLT. */
1492 if (h->type == STT_GNU_IFUNC)
1493 {
1494 /* All local STT_GNU_IFUNC references must be treate as local
1495 calls via local PLT. */
1496 if (h->ref_regular
1497 && SYMBOL_CALLS_LOCAL (info, h))
1498 {
1499 bfd_size_type pc_count = 0, count = 0;
1500 struct elf_dyn_relocs **pp;
1501
1502 eh = (struct elf_x86_link_hash_entry *) h;
1503 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1504 {
1505 pc_count += p->pc_count;
1506 p->count -= p->pc_count;
1507 p->pc_count = 0;
1508 count += p->count;
1509 if (p->count == 0)
1510 *pp = p->next;
1511 else
1512 pp = &p->next;
1513 }
1514
1515 if (pc_count || count)
1516 {
1517 h->non_got_ref = 1;
1518 if (pc_count)
1519 {
1520 /* Increment PLT reference count only for PC-relative
1521 references. */
1522 h->needs_plt = 1;
1523 if (h->plt.refcount <= 0)
1524 h->plt.refcount = 1;
1525 else
1526 h->plt.refcount += 1;
1527 }
1528 }
1529 }
1530
1531 if (h->plt.refcount <= 0)
1532 {
1533 h->plt.offset = (bfd_vma) -1;
1534 h->needs_plt = 0;
1535 }
1536 return TRUE;
1537 }
1538
1539 /* If this is a function, put it in the procedure linkage table. We
1540 will fill in the contents of the procedure linkage table later,
1541 when we know the address of the .got section. */
1542 if (h->type == STT_FUNC
1543 || h->needs_plt)
1544 {
1545 if (h->plt.refcount <= 0
1546 || SYMBOL_CALLS_LOCAL (info, h)
1547 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1548 && h->root.type == bfd_link_hash_undefweak))
1549 {
1550 /* This case can occur if we saw a PLT32 reloc in an input
1551 file, but the symbol was never referred to by a dynamic
1552 object, or if all references were garbage collected. In
1553 such a case, we don't actually need to build a procedure
1554 linkage table, and we can just do a PC32 reloc instead. */
1555 h->plt.offset = (bfd_vma) -1;
1556 h->needs_plt = 0;
1557 }
1558
1559 return TRUE;
1560 }
1561 else
1562 /* It's possible that we incorrectly decided a .plt reloc was needed
1563 * for an R_386_PC32/R_X86_64_PC32 reloc to a non-function sym in
1564 check_relocs. We can't decide accurately between function and
1565 non-function syms in check-relocs; Objects loaded later in
1566 the link may change h->type. So fix it now. */
1567 h->plt.offset = (bfd_vma) -1;
1568
1569 eh = (struct elf_x86_link_hash_entry *) h;
1570
1571 /* If this is a weak symbol, and there is a real definition, the
1572 processor independent code will have arranged for us to see the
1573 real definition first, and we can just use the same value. */
1574 if (h->u.weakdef != NULL)
1575 {
1576 BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined
1577 || h->u.weakdef->root.type == bfd_link_hash_defweak);
1578 h->root.u.def.section = h->u.weakdef->root.u.def.section;
1579 h->root.u.def.value = h->u.weakdef->root.u.def.value;
1580 if (ELIMINATE_COPY_RELOCS
1581 || info->nocopyreloc
1582 || SYMBOL_NO_COPYRELOC (info, eh))
1583 {
1584 /* NB: needs_copy is always 0 for i386. */
1585 h->non_got_ref = h->u.weakdef->non_got_ref;
1586 eh->needs_copy = h->u.weakdef->needs_copy;
1587 }
1588 return TRUE;
1589 }
1590
1591 /* This is a reference to a symbol defined by a dynamic object which
1592 is not a function. */
1593
1594 /* If we are creating a shared library, we must presume that the
1595 only references to the symbol are via the global offset table.
1596 For such cases we need not do anything here; the relocations will
1597 be handled correctly by relocate_section. */
1598 if (!bfd_link_executable (info))
1599 return TRUE;
1600
1601 /* If there are no references to this symbol that do not use the
1602 GOT nor R_386_GOTOFF relocation, we don't need to generate a copy
1603 reloc. NB: gotoff_ref is always 0 for x86-64. */
1604 if (!h->non_got_ref && !eh->gotoff_ref)
1605 return TRUE;
1606
1607 /* If -z nocopyreloc was given, we won't generate them either. */
1608 if (info->nocopyreloc || SYMBOL_NO_COPYRELOC (info, eh))
1609 {
1610 h->non_got_ref = 0;
1611 return TRUE;
1612 }
1613
1614 htab = elf_x86_hash_table (info, bed->target_id);
1615 if (htab == NULL)
1616 return FALSE;
1617
1618 /* If there aren't any dynamic relocs in read-only sections nor
1619 R_386_GOTOFF relocation, then we can keep the dynamic relocs and
1620 avoid the copy reloc. This doesn't work on VxWorks, where we can
1621 not have dynamic relocations (other than copy and jump slot
1622 relocations) in an executable. */
1623 if (ELIMINATE_COPY_RELOCS
1624 && (bed->target_id == X86_64_ELF_DATA
1625 || (!eh->gotoff_ref
1626 && !htab->is_vxworks)))
1627 {
1628 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1629 {
1630 s = p->sec->output_section;
1631 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1632 break;
1633 }
1634
1635 /* If we didn't find any dynamic relocs in read-only sections,
1636 then we'll be keeping the dynamic relocs and avoiding the copy
1637 reloc. */
1638 if (p == NULL)
1639 {
1640 h->non_got_ref = 0;
1641 return TRUE;
1642 }
1643 }
1644
1645 /* We must allocate the symbol in our .dynbss section, which will
1646 become part of the .bss section of the executable. There will be
1647 an entry for this symbol in the .dynsym section. The dynamic
1648 object will contain position independent code, so all references
1649 from the dynamic object to this symbol will go through the global
1650 offset table. The dynamic linker will use the .dynsym entry to
1651 determine the address it must put in the global offset table, so
1652 both the dynamic object and the regular object will refer to the
1653 same memory location for the variable. */
1654
1655 /* We must generate a R_386_COPY/R_X86_64_COPY reloc to tell the
1656 dynamic linker to copy the initial value out of the dynamic object
1657 and into the runtime process image. */
1658 if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
1659 {
1660 s = htab->elf.sdynrelro;
1661 srel = htab->elf.sreldynrelro;
1662 }
1663 else
1664 {
1665 s = htab->elf.sdynbss;
1666 srel = htab->elf.srelbss;
1667 }
1668 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
1669 {
1670 srel->size += htab->sizeof_reloc;
1671 h->needs_copy = 1;
1672 }
1673
1674 return _bfd_elf_adjust_dynamic_copy (info, h, s);
1675 }
1676
1677 /* Return the section that should be marked against GC for a given
1678 relocation. */
1679
1680 asection *
1681 _bfd_x86_elf_gc_mark_hook (asection *sec,
1682 struct bfd_link_info *info,
1683 Elf_Internal_Rela *rel,
1684 struct elf_link_hash_entry *h,
1685 Elf_Internal_Sym *sym)
1686 {
1687 /* Compiler should optimize this out. */
1688 if (((unsigned int) R_X86_64_GNU_VTINHERIT
1689 != (unsigned int) R_386_GNU_VTINHERIT)
1690 || ((unsigned int) R_X86_64_GNU_VTENTRY
1691 != (unsigned int) R_386_GNU_VTENTRY))
1692 abort ();
1693
1694 if (h != NULL)
1695 switch (ELF32_R_TYPE (rel->r_info))
1696 {
1697 case R_X86_64_GNU_VTINHERIT:
1698 case R_X86_64_GNU_VTENTRY:
1699 return NULL;
1700 }
1701
1702 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
1703 }
1704
1705 static bfd_vma
1706 elf_i386_get_plt_got_vma (struct elf_x86_plt *plt_p ATTRIBUTE_UNUSED,
1707 bfd_vma off,
1708 bfd_vma offset ATTRIBUTE_UNUSED,
1709 bfd_vma got_addr)
1710 {
1711 return got_addr + off;
1712 }
1713
1714 static bfd_vma
1715 elf_x86_64_get_plt_got_vma (struct elf_x86_plt *plt_p,
1716 bfd_vma off,
1717 bfd_vma offset,
1718 bfd_vma got_addr ATTRIBUTE_UNUSED)
1719 {
1720 return plt_p->sec->vma + offset + off + plt_p->plt_got_insn_size;
1721 }
1722
1723 static bfd_boolean
1724 elf_i386_valid_plt_reloc_p (unsigned int type)
1725 {
1726 return (type == R_386_JUMP_SLOT
1727 || type == R_386_GLOB_DAT
1728 || type == R_386_IRELATIVE);
1729 }
1730
1731 static bfd_boolean
1732 elf_x86_64_valid_plt_reloc_p (unsigned int type)
1733 {
1734 return (type == R_X86_64_JUMP_SLOT
1735 || type == R_X86_64_GLOB_DAT
1736 || type == R_X86_64_IRELATIVE);
1737 }
1738
1739 long
1740 _bfd_x86_elf_get_synthetic_symtab (bfd *abfd,
1741 long count,
1742 long relsize,
1743 bfd_vma got_addr,
1744 struct elf_x86_plt plts[],
1745 asymbol **dynsyms,
1746 asymbol **ret)
1747 {
1748 long size, i, n, len;
1749 int j;
1750 unsigned int plt_got_offset, plt_entry_size;
1751 asymbol *s;
1752 bfd_byte *plt_contents;
1753 long dynrelcount;
1754 arelent **dynrelbuf, *p;
1755 char *names;
1756 const struct elf_backend_data *bed;
1757 bfd_vma (*get_plt_got_vma) (struct elf_x86_plt *, bfd_vma, bfd_vma,
1758 bfd_vma);
1759 bfd_boolean (*valid_plt_reloc_p) (unsigned int);
1760
1761 if (count == 0)
1762 return -1;
1763
1764 dynrelbuf = (arelent **) bfd_malloc (relsize);
1765 if (dynrelbuf == NULL)
1766 return -1;
1767
1768 dynrelcount = bfd_canonicalize_dynamic_reloc (abfd, dynrelbuf,
1769 dynsyms);
1770
1771 /* Sort the relocs by address. */
1772 qsort (dynrelbuf, dynrelcount, sizeof (arelent *),
1773 _bfd_x86_elf_compare_relocs);
1774
1775 size = count * sizeof (asymbol);
1776
1777 /* Allocate space for @plt suffixes. */
1778 n = 0;
1779 for (i = 0; i < dynrelcount; i++)
1780 {
1781 p = dynrelbuf[i];
1782 size += strlen ((*p->sym_ptr_ptr)->name) + sizeof ("@plt");
1783 if (p->addend != 0)
1784 size += sizeof ("+0x") - 1 + 8 + 8 * ABI_64_P (abfd);
1785 }
1786
1787 s = *ret = (asymbol *) bfd_zmalloc (size);
1788 if (s == NULL)
1789 goto bad_return;
1790
1791 bed = get_elf_backend_data (abfd);
1792
1793 if (bed->target_id == X86_64_ELF_DATA)
1794 {
1795 get_plt_got_vma = elf_x86_64_get_plt_got_vma;
1796 valid_plt_reloc_p = elf_x86_64_valid_plt_reloc_p;
1797 }
1798 else
1799 {
1800 get_plt_got_vma = elf_i386_get_plt_got_vma;
1801 valid_plt_reloc_p = elf_i386_valid_plt_reloc_p;
1802 if (got_addr)
1803 {
1804 /* Check .got.plt and then .got to get the _GLOBAL_OFFSET_TABLE_
1805 address. */
1806 asection *sec = bfd_get_section_by_name (abfd, ".got.plt");
1807 if (sec != NULL)
1808 got_addr = sec->vma;
1809 else
1810 {
1811 sec = bfd_get_section_by_name (abfd, ".got");
1812 if (sec != NULL)
1813 got_addr = sec->vma;
1814 }
1815
1816 if (got_addr == (bfd_vma) -1)
1817 goto bad_return;
1818 }
1819 }
1820
1821 /* Check for each PLT section. */
1822 names = (char *) (s + count);
1823 size = 0;
1824 n = 0;
1825 for (j = 0; plts[j].name != NULL; j++)
1826 if ((plt_contents = plts[j].contents) != NULL)
1827 {
1828 long k;
1829 bfd_vma offset;
1830 asection *plt;
1831 struct elf_x86_plt *plt_p = &plts[j];
1832
1833 plt_got_offset = plt_p->plt_got_offset;
1834 plt_entry_size = plt_p->plt_entry_size;
1835
1836 plt = plt_p->sec;
1837
1838 if ((plt_p->type & plt_lazy))
1839 {
1840 /* Skip PLT0 in lazy PLT. */
1841 k = 1;
1842 offset = plt_entry_size;
1843 }
1844 else
1845 {
1846 k = 0;
1847 offset = 0;
1848 }
1849
1850 /* Check each PLT entry against dynamic relocations. */
1851 for (; k < plt_p->count; k++)
1852 {
1853 int off;
1854 bfd_vma got_vma;
1855 long min, max, mid;
1856
1857 /* Get the GOT offset for i386 or the PC-relative offset
1858 for x86-64, a signed 32-bit integer. */
1859 off = H_GET_32 (abfd, (plt_contents + offset
1860 + plt_got_offset));
1861 got_vma = get_plt_got_vma (plt_p, off, offset, got_addr);
1862
1863 /* Binary search. */
1864 p = dynrelbuf[0];
1865 min = 0;
1866 max = dynrelcount;
1867 while ((min + 1) < max)
1868 {
1869 arelent *r;
1870
1871 mid = (min + max) / 2;
1872 r = dynrelbuf[mid];
1873 if (got_vma > r->address)
1874 min = mid;
1875 else if (got_vma < r->address)
1876 max = mid;
1877 else
1878 {
1879 p = r;
1880 break;
1881 }
1882 }
1883
1884 /* Skip unknown relocation. PR 17512: file: bc9d6cf5. */
1885 if (got_vma == p->address
1886 && p->howto != NULL
1887 && valid_plt_reloc_p (p->howto->type))
1888 {
1889 *s = **p->sym_ptr_ptr;
1890 /* Undefined syms won't have BSF_LOCAL or BSF_GLOBAL
1891 set. Since we are defining a symbol, ensure one
1892 of them is set. */
1893 if ((s->flags & BSF_LOCAL) == 0)
1894 s->flags |= BSF_GLOBAL;
1895 s->flags |= BSF_SYNTHETIC;
1896 /* This is no longer a section symbol. */
1897 s->flags &= ~BSF_SECTION_SYM;
1898 s->section = plt;
1899 s->the_bfd = plt->owner;
1900 s->value = offset;
1901 s->udata.p = NULL;
1902 s->name = names;
1903 len = strlen ((*p->sym_ptr_ptr)->name);
1904 memcpy (names, (*p->sym_ptr_ptr)->name, len);
1905 names += len;
1906 if (p->addend != 0)
1907 {
1908 char buf[30], *a;
1909
1910 memcpy (names, "+0x", sizeof ("+0x") - 1);
1911 names += sizeof ("+0x") - 1;
1912 bfd_sprintf_vma (abfd, buf, p->addend);
1913 for (a = buf; *a == '0'; ++a)
1914 ;
1915 size = strlen (a);
1916 memcpy (names, a, size);
1917 names += size;
1918 }
1919 memcpy (names, "@plt", sizeof ("@plt"));
1920 names += sizeof ("@plt");
1921 n++;
1922 s++;
1923 }
1924 offset += plt_entry_size;
1925 }
1926 }
1927
1928 /* PLT entries with R_386_TLS_DESC relocations are skipped. */
1929 if (n == 0)
1930 {
1931 bad_return:
1932 count = -1;
1933 }
1934 else
1935 count = n;
1936
1937 for (j = 0; plts[j].name != NULL; j++)
1938 if (plts[j].contents != NULL)
1939 free (plts[j].contents);
1940
1941 free (dynrelbuf);
1942
1943 return count;
1944 }
1945
1946 /* Parse x86 GNU properties. */
1947
1948 enum elf_property_kind
1949 _bfd_x86_elf_parse_gnu_properties (bfd *abfd, unsigned int type,
1950 bfd_byte *ptr, unsigned int datasz)
1951 {
1952 elf_property *prop;
1953
1954 switch (type)
1955 {
1956 case GNU_PROPERTY_X86_ISA_1_USED:
1957 case GNU_PROPERTY_X86_ISA_1_NEEDED:
1958 case GNU_PROPERTY_X86_FEATURE_1_AND:
1959 if (datasz != 4)
1960 {
1961 _bfd_error_handler
1962 ((type == GNU_PROPERTY_X86_ISA_1_USED
1963 ? _("error: %B: <corrupt x86 ISA used size: 0x%x>")
1964 : (type == GNU_PROPERTY_X86_ISA_1_NEEDED
1965 ? _("error: %B: <corrupt x86 ISA needed size: 0x%x>")
1966 : _("error: %B: <corrupt x86 feature size: 0x%x>"))),
1967 abfd, datasz);
1968 return property_corrupt;
1969 }
1970 prop = _bfd_elf_get_property (abfd, type, datasz);
1971 /* Combine properties of the same type. */
1972 prop->u.number |= bfd_h_get_32 (abfd, ptr);
1973 prop->pr_kind = property_number;
1974 break;
1975
1976 default:
1977 return property_ignored;
1978 }
1979
1980 return property_number;
1981 }
1982
1983 /* Merge x86 GNU property BPROP with APROP. If APROP isn't NULL,
1984 return TRUE if APROP is updated. Otherwise, return TRUE if BPROP
1985 should be merged with ABFD. */
1986
1987 bfd_boolean
1988 _bfd_x86_elf_merge_gnu_properties (struct bfd_link_info *info,
1989 bfd *abfd ATTRIBUTE_UNUSED,
1990 elf_property *aprop,
1991 elf_property *bprop)
1992 {
1993 unsigned int number, features;
1994 bfd_boolean updated = FALSE;
1995 unsigned int pr_type = aprop != NULL ? aprop->pr_type : bprop->pr_type;
1996
1997 switch (pr_type)
1998 {
1999 case GNU_PROPERTY_X86_ISA_1_USED:
2000 case GNU_PROPERTY_X86_ISA_1_NEEDED:
2001 if (aprop != NULL && bprop != NULL)
2002 {
2003 number = aprop->u.number;
2004 aprop->u.number = number | bprop->u.number;
2005 updated = number != (unsigned int) aprop->u.number;
2006 }
2007 else
2008 {
2009 /* Return TRUE if APROP is NULL to indicate that BPROP should
2010 be added to ABFD. */
2011 updated = aprop == NULL;
2012 }
2013 break;
2014
2015 case GNU_PROPERTY_X86_FEATURE_1_AND:
2016 /* Only one of APROP and BPROP can be NULL:
2017 1. APROP & BPROP when both APROP and BPROP aren't NULL.
2018 2. If APROP is NULL, remove x86 feature.
2019 3. Otherwise, do nothing.
2020 */
2021 if (aprop != NULL && bprop != NULL)
2022 {
2023 features = 0;
2024 if (info->ibt)
2025 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2026 if (info->shstk)
2027 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2028 number = aprop->u.number;
2029 /* Add GNU_PROPERTY_X86_FEATURE_1_IBT and
2030 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2031 aprop->u.number = (number & bprop->u.number) | features;
2032 updated = number != (unsigned int) aprop->u.number;
2033 /* Remove the property if all feature bits are cleared. */
2034 if (aprop->u.number == 0)
2035 aprop->pr_kind = property_remove;
2036 }
2037 else
2038 {
2039 features = 0;
2040 if (info->ibt)
2041 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2042 if (info->shstk)
2043 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2044 if (features)
2045 {
2046 /* Add GNU_PROPERTY_X86_FEATURE_1_IBT and
2047 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2048 if (aprop != NULL)
2049 {
2050 number = aprop->u.number;
2051 aprop->u.number = number | features;
2052 updated = number != (unsigned int) aprop->u.number;
2053 }
2054 else
2055 {
2056 bprop->u.number |= features;
2057 updated = TRUE;
2058 }
2059 }
2060 else if (aprop != NULL)
2061 {
2062 aprop->pr_kind = property_remove;
2063 updated = TRUE;
2064 }
2065 }
2066 break;
2067
2068 default:
2069 /* Never should happen. */
2070 abort ();
2071 }
2072
2073 return updated;
2074 }
2075
2076 /* Set up x86 GNU properties. Return the first relocatable ELF input
2077 with GNU properties if found. Otherwise, return NULL. */
2078
2079 bfd *
2080 _bfd_x86_elf_link_setup_gnu_properties
2081 (struct bfd_link_info *info,
2082 struct elf_x86_plt_layout_table *plt_layout)
2083 {
2084 bfd_boolean normal_target;
2085 bfd_boolean lazy_plt;
2086 asection *sec, *pltsec;
2087 bfd *dynobj;
2088 bfd_boolean use_ibt_plt;
2089 unsigned int plt_alignment, features;
2090 struct elf_x86_link_hash_table *htab;
2091 bfd *pbfd;
2092 bfd *ebfd = NULL;
2093 elf_property *prop;
2094 const struct elf_backend_data *bed;
2095 unsigned int class_align = ABI_64_P (info->output_bfd) ? 3 : 2;
2096 unsigned int got_align;
2097
2098 features = 0;
2099 if (info->ibt)
2100 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2101 if (info->shstk)
2102 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2103
2104 /* Find a normal input file with GNU property note. */
2105 for (pbfd = info->input_bfds;
2106 pbfd != NULL;
2107 pbfd = pbfd->link.next)
2108 if (bfd_get_flavour (pbfd) == bfd_target_elf_flavour
2109 && bfd_count_sections (pbfd) != 0)
2110 {
2111 ebfd = pbfd;
2112
2113 if (elf_properties (pbfd) != NULL)
2114 break;
2115 }
2116
2117 if (ebfd != NULL && features)
2118 {
2119 /* If features is set, add GNU_PROPERTY_X86_FEATURE_1_IBT and
2120 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2121 prop = _bfd_elf_get_property (ebfd,
2122 GNU_PROPERTY_X86_FEATURE_1_AND,
2123 4);
2124 prop->u.number |= features;
2125 prop->pr_kind = property_number;
2126
2127 /* Create the GNU property note section if needed. */
2128 if (pbfd == NULL)
2129 {
2130 sec = bfd_make_section_with_flags (ebfd,
2131 NOTE_GNU_PROPERTY_SECTION_NAME,
2132 (SEC_ALLOC
2133 | SEC_LOAD
2134 | SEC_IN_MEMORY
2135 | SEC_READONLY
2136 | SEC_HAS_CONTENTS
2137 | SEC_DATA));
2138 if (sec == NULL)
2139 info->callbacks->einfo (_("%F: failed to create GNU property section\n"));
2140
2141 if (!bfd_set_section_alignment (ebfd, sec, class_align))
2142 {
2143 error_alignment:
2144 info->callbacks->einfo (_("%F%A: failed to align section\n"),
2145 sec);
2146 }
2147
2148 elf_section_type (sec) = SHT_NOTE;
2149 }
2150 }
2151
2152 pbfd = _bfd_elf_link_setup_gnu_properties (info);
2153
2154 if (bfd_link_relocatable (info))
2155 return pbfd;
2156
2157 bed = get_elf_backend_data (info->output_bfd);
2158
2159 htab = elf_x86_hash_table (info, bed->target_id);
2160 if (htab == NULL)
2161 return pbfd;
2162
2163 htab->is_vxworks = plt_layout->is_vxworks;
2164
2165 use_ibt_plt = info->ibtplt || info->ibt;
2166 if (!use_ibt_plt && pbfd != NULL)
2167 {
2168 /* Check if GNU_PROPERTY_X86_FEATURE_1_IBT is on. */
2169 elf_property_list *p;
2170
2171 /* The property list is sorted in order of type. */
2172 for (p = elf_properties (pbfd); p; p = p->next)
2173 {
2174 if (GNU_PROPERTY_X86_FEATURE_1_AND == p->property.pr_type)
2175 {
2176 use_ibt_plt = !!(p->property.u.number
2177 & GNU_PROPERTY_X86_FEATURE_1_IBT);
2178 break;
2179 }
2180 else if (GNU_PROPERTY_X86_FEATURE_1_AND < p->property.pr_type)
2181 break;
2182 }
2183 }
2184
2185 dynobj = htab->elf.dynobj;
2186
2187 /* Set htab->elf.dynobj here so that there is no need to check and
2188 set it in check_relocs. */
2189 if (dynobj == NULL)
2190 {
2191 if (pbfd != NULL)
2192 {
2193 htab->elf.dynobj = pbfd;
2194 dynobj = pbfd;
2195 }
2196 else
2197 {
2198 bfd *abfd;
2199
2200 /* Find a normal input file to hold linker created
2201 sections. */
2202 for (abfd = info->input_bfds;
2203 abfd != NULL;
2204 abfd = abfd->link.next)
2205 if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
2206 && (abfd->flags
2207 & (DYNAMIC | BFD_LINKER_CREATED | BFD_PLUGIN)) == 0)
2208 {
2209 htab->elf.dynobj = abfd;
2210 dynobj = abfd;
2211 break;
2212 }
2213 }
2214 }
2215
2216 /* Even when lazy binding is disabled by "-z now", the PLT0 entry may
2217 still be used with LD_AUDIT or LD_PROFILE if PLT entry is used for
2218 canonical function address. */
2219 htab->plt.has_plt0 = 1;
2220 normal_target = plt_layout->normal_target;
2221
2222 if (normal_target)
2223 {
2224 if (use_ibt_plt)
2225 {
2226 htab->lazy_plt = plt_layout->lazy_ibt_plt;
2227 htab->non_lazy_plt = plt_layout->non_lazy_ibt_plt;
2228 }
2229 else
2230 {
2231 htab->lazy_plt = plt_layout->lazy_plt;
2232 htab->non_lazy_plt = plt_layout->non_lazy_plt;
2233 }
2234 }
2235 else
2236 {
2237 htab->lazy_plt = plt_layout->lazy_plt;
2238 htab->non_lazy_plt = NULL;
2239 }
2240
2241 pltsec = htab->elf.splt;
2242
2243 /* If the non-lazy PLT is available, use it for all PLT entries if
2244 there are no PLT0 or no .plt section. */
2245 if (htab->non_lazy_plt != NULL
2246 && (!htab->plt.has_plt0 || pltsec == NULL))
2247 {
2248 lazy_plt = FALSE;
2249 if (bfd_link_pic (info))
2250 htab->plt.plt_entry = htab->non_lazy_plt->pic_plt_entry;
2251 else
2252 htab->plt.plt_entry = htab->non_lazy_plt->plt_entry;
2253 htab->plt.plt_entry_size = htab->non_lazy_plt->plt_entry_size;
2254 htab->plt.plt_got_offset = htab->non_lazy_plt->plt_got_offset;
2255 htab->plt.plt_got_insn_size
2256 = htab->non_lazy_plt->plt_got_insn_size;
2257 htab->plt.eh_frame_plt_size
2258 = htab->non_lazy_plt->eh_frame_plt_size;
2259 htab->plt.eh_frame_plt = htab->non_lazy_plt->eh_frame_plt;
2260 }
2261 else
2262 {
2263 lazy_plt = TRUE;
2264 if (bfd_link_pic (info))
2265 {
2266 htab->plt.plt0_entry = htab->lazy_plt->pic_plt0_entry;
2267 htab->plt.plt_entry = htab->lazy_plt->pic_plt_entry;
2268 }
2269 else
2270 {
2271 htab->plt.plt0_entry = htab->lazy_plt->plt0_entry;
2272 htab->plt.plt_entry = htab->lazy_plt->plt_entry;
2273 }
2274 htab->plt.plt_entry_size = htab->lazy_plt->plt_entry_size;
2275 htab->plt.plt_got_offset = htab->lazy_plt->plt_got_offset;
2276 htab->plt.plt_got_insn_size
2277 = htab->lazy_plt->plt_got_insn_size;
2278 htab->plt.eh_frame_plt_size
2279 = htab->lazy_plt->eh_frame_plt_size;
2280 htab->plt.eh_frame_plt = htab->lazy_plt->eh_frame_plt;
2281 }
2282
2283 /* Return if there are no normal input files. */
2284 if (dynobj == NULL)
2285 return pbfd;
2286
2287 if (htab->is_vxworks
2288 && !elf_vxworks_create_dynamic_sections (dynobj, info,
2289 &htab->srelplt2))
2290 {
2291 info->callbacks->einfo (_("%F: failed to create VxWorks dynamic sections\n"));
2292 return pbfd;
2293 }
2294
2295 /* Since create_dynamic_sections isn't always called, but GOT
2296 relocations need GOT relocations, create them here so that we
2297 don't need to do it in check_relocs. */
2298 if (htab->elf.sgot == NULL
2299 && !_bfd_elf_create_got_section (dynobj, info))
2300 info->callbacks->einfo (_("%F: failed to create GOT sections\n"));
2301
2302 got_align = (bed->target_id == X86_64_ELF_DATA) ? 3 : 2;
2303
2304 /* Align .got and .got.plt sections to their entry size. Do it here
2305 instead of in create_dynamic_sections so that they are always
2306 properly aligned even if create_dynamic_sections isn't called. */
2307 sec = htab->elf.sgot;
2308 if (!bfd_set_section_alignment (dynobj, sec, got_align))
2309 goto error_alignment;
2310
2311 sec = htab->elf.sgotplt;
2312 if (!bfd_set_section_alignment (dynobj, sec, got_align))
2313 goto error_alignment;
2314
2315 /* Create the ifunc sections here so that check_relocs can be
2316 simplified. */
2317 if (!_bfd_elf_create_ifunc_sections (dynobj, info))
2318 info->callbacks->einfo (_("%F: failed to create ifunc sections\n"));
2319
2320 plt_alignment = bfd_log2 (htab->plt.plt_entry_size);
2321
2322 if (pltsec != NULL)
2323 {
2324 /* Whe creating executable, set the contents of the .interp
2325 section to the interpreter. */
2326 if (bfd_link_executable (info) && !info->nointerp)
2327 {
2328 asection *s = bfd_get_linker_section (dynobj, ".interp");
2329 if (s == NULL)
2330 abort ();
2331 s->size = htab->dynamic_interpreter_size;
2332 s->contents = (unsigned char *) htab->dynamic_interpreter;
2333 htab->interp = s;
2334 }
2335
2336 /* Don't change PLT section alignment for NaCl since it uses
2337 64-byte PLT entry and sets PLT section alignment to 32
2338 bytes. Don't create additional PLT sections for NaCl. */
2339 if (normal_target)
2340 {
2341 flagword pltflags = (bed->dynamic_sec_flags
2342 | SEC_ALLOC
2343 | SEC_CODE
2344 | SEC_LOAD
2345 | SEC_READONLY);
2346 unsigned int non_lazy_plt_alignment
2347 = bfd_log2 (htab->non_lazy_plt->plt_entry_size);
2348
2349 sec = pltsec;
2350 if (!bfd_set_section_alignment (sec->owner, sec,
2351 plt_alignment))
2352 goto error_alignment;
2353
2354 /* Create the GOT procedure linkage table. */
2355 sec = bfd_make_section_anyway_with_flags (dynobj,
2356 ".plt.got",
2357 pltflags);
2358 if (sec == NULL)
2359 info->callbacks->einfo (_("%F: failed to create GOT PLT section\n"));
2360
2361 if (!bfd_set_section_alignment (dynobj, sec,
2362 non_lazy_plt_alignment))
2363 goto error_alignment;
2364
2365 htab->plt_got = sec;
2366
2367 if (lazy_plt)
2368 {
2369 sec = NULL;
2370
2371 if (use_ibt_plt)
2372 {
2373 /* Create the second PLT for Intel IBT support. IBT
2374 PLT is supported only for non-NaCl target and is
2375 is needed only for lazy binding. */
2376 sec = bfd_make_section_anyway_with_flags (dynobj,
2377 ".plt.sec",
2378 pltflags);
2379 if (sec == NULL)
2380 info->callbacks->einfo (_("%F: failed to create IBT-enabled PLT section\n"));
2381
2382 if (!bfd_set_section_alignment (dynobj, sec,
2383 plt_alignment))
2384 goto error_alignment;
2385 }
2386 else if (info->bndplt && ABI_64_P (dynobj))
2387 {
2388 /* Create the second PLT for Intel MPX support. MPX
2389 PLT is supported only for non-NaCl target in 64-bit
2390 mode and is needed only for lazy binding. */
2391 sec = bfd_make_section_anyway_with_flags (dynobj,
2392 ".plt.sec",
2393 pltflags);
2394 if (sec == NULL)
2395 info->callbacks->einfo (_("%F: failed to create BND PLT section\n"));
2396
2397 if (!bfd_set_section_alignment (dynobj, sec,
2398 non_lazy_plt_alignment))
2399 goto error_alignment;
2400 }
2401
2402 htab->plt_second = sec;
2403 }
2404 }
2405
2406 if (!info->no_ld_generated_unwind_info)
2407 {
2408 flagword flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY
2409 | SEC_HAS_CONTENTS | SEC_IN_MEMORY
2410 | SEC_LINKER_CREATED);
2411
2412 sec = bfd_make_section_anyway_with_flags (dynobj,
2413 ".eh_frame",
2414 flags);
2415 if (sec == NULL)
2416 info->callbacks->einfo (_("%F: failed to create PLT .eh_frame section\n"));
2417
2418 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2419 goto error_alignment;
2420
2421 htab->plt_eh_frame = sec;
2422
2423 if (htab->plt_got != NULL)
2424 {
2425 sec = bfd_make_section_anyway_with_flags (dynobj,
2426 ".eh_frame",
2427 flags);
2428 if (sec == NULL)
2429 info->callbacks->einfo (_("%F: failed to create GOT PLT .eh_frame section\n"));
2430
2431 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2432 goto error_alignment;
2433
2434 htab->plt_got_eh_frame = sec;
2435 }
2436
2437 if (htab->plt_second != NULL)
2438 {
2439 sec = bfd_make_section_anyway_with_flags (dynobj,
2440 ".eh_frame",
2441 flags);
2442 if (sec == NULL)
2443 info->callbacks->einfo (_("%F: failed to create the second PLT .eh_frame section\n"));
2444
2445 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2446 goto error_alignment;
2447
2448 htab->plt_second_eh_frame = sec;
2449 }
2450 }
2451 }
2452
2453 if (normal_target)
2454 {
2455 /* The .iplt section is used for IFUNC symbols in static
2456 executables. */
2457 sec = htab->elf.iplt;
2458 if (sec != NULL
2459 && !bfd_set_section_alignment (sec->owner, sec,
2460 plt_alignment))
2461 goto error_alignment;
2462 }
2463
2464 return pbfd;
2465 }