x86-64: Set tlsdesc_plt if GOT_TLS_GDESC_P is true
[deliverable/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 {
372 htab->elf.srelplt->size += htab->sizeof_reloc;
373 if (bed->target_id == X86_64_ELF_DATA)
374 htab->tlsdesc_plt = (bfd_vma) -1;
375 }
376 }
377 else
378 h->got.offset = (bfd_vma) -1;
379
380 if (eh->dyn_relocs == NULL)
381 return TRUE;
382
383 /* In the shared -Bsymbolic case, discard space allocated for
384 dynamic pc-relative relocs against symbols which turn out to be
385 defined in regular objects. For the normal shared case, discard
386 space for pc-relative relocs that have become local due to symbol
387 visibility changes. */
388
389 if (bfd_link_pic (info))
390 {
391 /* Relocs that use pc_count are those that appear on a call
392 insn, or certain REL relocs that can generated via assembly.
393 We want calls to protected symbols to resolve directly to the
394 function rather than going via the plt. If people want
395 function pointer comparisons to work as expected then they
396 should avoid writing weird assembly. */
397 if (SYMBOL_CALLS_LOCAL (info, h))
398 {
399 struct elf_dyn_relocs **pp;
400
401 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
402 {
403 p->count -= p->pc_count;
404 p->pc_count = 0;
405 if (p->count == 0)
406 *pp = p->next;
407 else
408 pp = &p->next;
409 }
410 }
411
412 if (htab->is_vxworks)
413 {
414 struct elf_dyn_relocs **pp;
415 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
416 {
417 if (strcmp (p->sec->output_section->name, ".tls_vars") == 0)
418 *pp = p->next;
419 else
420 pp = &p->next;
421 }
422 }
423
424 /* Also discard relocs on undefined weak syms with non-default
425 visibility or in PIE. */
426 if (eh->dyn_relocs != NULL)
427 {
428 if (h->root.type == bfd_link_hash_undefweak)
429 {
430 /* Undefined weak symbol is never bound locally in shared
431 library. */
432 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
433 || resolved_to_zero)
434 {
435 if (bed->target_id == I386_ELF_DATA
436 && h->non_got_ref)
437 {
438 /* Keep dynamic non-GOT/non-PLT relocation so
439 that we can branch to 0 without PLT. */
440 struct elf_dyn_relocs **pp;
441
442 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
443 if (p->pc_count == 0)
444 *pp = p->next;
445 else
446 {
447 /* Remove non-R_386_PC32 relocation. */
448 p->count = p->pc_count;
449 pp = &p->next;
450 }
451
452 /* Make sure undefined weak symbols are output
453 as dynamic symbols in PIEs for dynamic non-GOT
454 non-PLT reloations. */
455 if (eh->dyn_relocs != NULL
456 && !bfd_elf_link_record_dynamic_symbol (info, h))
457 return FALSE;
458 }
459 else
460 eh->dyn_relocs = NULL;
461 }
462 else if (h->dynindx == -1
463 && !h->forced_local
464 && !bfd_elf_link_record_dynamic_symbol (info, h))
465 return FALSE;
466 }
467 else if (bfd_link_executable (info)
468 && (h->needs_copy || eh->needs_copy)
469 && h->def_dynamic
470 && !h->def_regular)
471 {
472 /* NB: needs_copy is set only for x86-64. For PIE,
473 discard space for pc-relative relocs against symbols
474 which turn out to need copy relocs. */
475 struct elf_dyn_relocs **pp;
476
477 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
478 {
479 if (p->pc_count != 0)
480 *pp = p->next;
481 else
482 pp = &p->next;
483 }
484 }
485 }
486 }
487 else if (ELIMINATE_COPY_RELOCS)
488 {
489 /* For the non-shared case, discard space for relocs against
490 symbols which turn out to need copy relocs or are not
491 dynamic. Keep dynamic relocations for run-time function
492 pointer initialization. */
493
494 if ((!h->non_got_ref
495 || eh->func_pointer_refcount > 0
496 || (h->root.type == bfd_link_hash_undefweak
497 && !resolved_to_zero))
498 && ((h->def_dynamic
499 && !h->def_regular)
500 || (htab->elf.dynamic_sections_created
501 && (h->root.type == bfd_link_hash_undefweak
502 || h->root.type == bfd_link_hash_undefined))))
503 {
504 /* Make sure this symbol is output as a dynamic symbol.
505 Undefined weak syms won't yet be marked as dynamic. */
506 if (h->dynindx == -1
507 && !h->forced_local
508 && !resolved_to_zero
509 && h->root.type == bfd_link_hash_undefweak
510 && ! bfd_elf_link_record_dynamic_symbol (info, h))
511 return FALSE;
512
513 /* If that succeeded, we know we'll be keeping all the
514 relocs. */
515 if (h->dynindx != -1)
516 goto keep;
517 }
518
519 eh->dyn_relocs = NULL;
520 eh->func_pointer_refcount = 0;
521
522 keep: ;
523 }
524
525 /* Finally, allocate space. */
526 for (p = eh->dyn_relocs; p != NULL; p = p->next)
527 {
528 asection *sreloc;
529
530 sreloc = elf_section_data (p->sec)->sreloc;
531
532 BFD_ASSERT (sreloc != NULL);
533 sreloc->size += p->count * htab->sizeof_reloc;
534 }
535
536 return TRUE;
537 }
538
539 /* Find any dynamic relocs that apply to read-only sections. */
540
541 bfd_boolean
542 _bfd_x86_elf_readonly_dynrelocs (struct elf_link_hash_entry *h,
543 void *inf)
544 {
545 struct elf_x86_link_hash_entry *eh;
546 struct elf_dyn_relocs *p;
547
548 /* Skip local IFUNC symbols. */
549 if (h->forced_local && h->type == STT_GNU_IFUNC)
550 return TRUE;
551
552 eh = (struct elf_x86_link_hash_entry *) h;
553 for (p = eh->dyn_relocs; p != NULL; p = p->next)
554 {
555 asection *s = p->sec->output_section;
556
557 if (s != NULL && (s->flags & SEC_READONLY) != 0)
558 {
559 struct bfd_link_info *info = (struct bfd_link_info *) inf;
560
561 info->flags |= DF_TEXTREL;
562
563 if ((info->warn_shared_textrel && bfd_link_pic (info))
564 || info->error_textrel)
565 /* xgettext:c-format */
566 info->callbacks->einfo (_("%P: %B: warning: relocation against `%s' in readonly section `%A'\n"),
567 p->sec->owner, h->root.root.string,
568 p->sec);
569
570 /* Not an error, just cut short the traversal. */
571 return FALSE;
572 }
573 }
574 return TRUE;
575 }
576
577 /* Allocate space in .plt, .got and associated reloc sections for
578 local dynamic relocs. */
579
580 static bfd_boolean
581 elf_x86_allocate_local_dynreloc (void **slot, void *inf)
582 {
583 struct elf_link_hash_entry *h
584 = (struct elf_link_hash_entry *) *slot;
585
586 if (h->type != STT_GNU_IFUNC
587 || !h->def_regular
588 || !h->ref_regular
589 || !h->forced_local
590 || h->root.type != bfd_link_hash_defined)
591 abort ();
592
593 return elf_x86_allocate_dynrelocs (h, inf);
594 }
595
596 /* Find and/or create a hash entry for local symbol. */
597
598 struct elf_link_hash_entry *
599 _bfd_elf_x86_get_local_sym_hash (struct elf_x86_link_hash_table *htab,
600 bfd *abfd, const Elf_Internal_Rela *rel,
601 bfd_boolean create)
602 {
603 struct elf_x86_link_hash_entry e, *ret;
604 asection *sec = abfd->sections;
605 hashval_t h = ELF_LOCAL_SYMBOL_HASH (sec->id,
606 htab->r_sym (rel->r_info));
607 void **slot;
608
609 e.elf.indx = sec->id;
610 e.elf.dynstr_index = htab->r_sym (rel->r_info);
611 slot = htab_find_slot_with_hash (htab->loc_hash_table, &e, h,
612 create ? INSERT : NO_INSERT);
613
614 if (!slot)
615 return NULL;
616
617 if (*slot)
618 {
619 ret = (struct elf_x86_link_hash_entry *) *slot;
620 return &ret->elf;
621 }
622
623 ret = (struct elf_x86_link_hash_entry *)
624 objalloc_alloc ((struct objalloc *) htab->loc_hash_memory,
625 sizeof (struct elf_x86_link_hash_entry));
626 if (ret)
627 {
628 memset (ret, 0, sizeof (*ret));
629 ret->elf.indx = sec->id;
630 ret->elf.dynstr_index = htab->r_sym (rel->r_info);
631 ret->elf.dynindx = -1;
632 ret->plt_got.offset = (bfd_vma) -1;
633 *slot = ret;
634 }
635 return &ret->elf;
636 }
637
638 /* Create an entry in a x86 ELF linker hash table. NB: THIS MUST BE IN
639 SYNC WITH _bfd_elf_link_hash_newfunc. */
640
641 struct bfd_hash_entry *
642 _bfd_x86_elf_link_hash_newfunc (struct bfd_hash_entry *entry,
643 struct bfd_hash_table *table,
644 const char *string)
645 {
646 /* Allocate the structure if it has not already been allocated by a
647 subclass. */
648 if (entry == NULL)
649 {
650 entry = (struct bfd_hash_entry *)
651 bfd_hash_allocate (table,
652 sizeof (struct elf_x86_link_hash_entry));
653 if (entry == NULL)
654 return entry;
655 }
656
657 /* Call the allocation method of the superclass. */
658 entry = _bfd_link_hash_newfunc (entry, table, string);
659 if (entry != NULL)
660 {
661 struct elf_x86_link_hash_entry *eh
662 = (struct elf_x86_link_hash_entry *) entry;
663 struct elf_link_hash_table *htab
664 = (struct elf_link_hash_table *) table;
665
666 memset (&eh->elf.size, 0,
667 (sizeof (struct elf_x86_link_hash_entry)
668 - offsetof (struct elf_link_hash_entry, size)));
669 /* Set local fields. */
670 eh->elf.indx = -1;
671 eh->elf.dynindx = -1;
672 eh->elf.got = htab->init_got_refcount;
673 eh->elf.plt = htab->init_plt_refcount;
674 /* Assume that we have been called by a non-ELF symbol reader.
675 This flag is then reset by the code which reads an ELF input
676 file. This ensures that a symbol created by a non-ELF symbol
677 reader will have the flag set correctly. */
678 eh->elf.non_elf = 1;
679 eh->plt_second.offset = (bfd_vma) -1;
680 eh->plt_got.offset = (bfd_vma) -1;
681 eh->tlsdesc_got = (bfd_vma) -1;
682 }
683
684 return entry;
685 }
686
687 /* Compute a hash of a local hash entry. We use elf_link_hash_entry
688 for local symbol so that we can handle local STT_GNU_IFUNC symbols
689 as global symbol. We reuse indx and dynstr_index for local symbol
690 hash since they aren't used by global symbols in this backend. */
691
692 hashval_t
693 _bfd_x86_elf_local_htab_hash (const void *ptr)
694 {
695 struct elf_link_hash_entry *h
696 = (struct elf_link_hash_entry *) ptr;
697 return ELF_LOCAL_SYMBOL_HASH (h->indx, h->dynstr_index);
698 }
699
700 /* Compare local hash entries. */
701
702 int
703 _bfd_x86_elf_local_htab_eq (const void *ptr1, const void *ptr2)
704 {
705 struct elf_link_hash_entry *h1
706 = (struct elf_link_hash_entry *) ptr1;
707 struct elf_link_hash_entry *h2
708 = (struct elf_link_hash_entry *) ptr2;
709
710 return h1->indx == h2->indx && h1->dynstr_index == h2->dynstr_index;
711 }
712
713 /* Destroy an x86 ELF linker hash table. */
714
715 static void
716 elf_x86_link_hash_table_free (bfd *obfd)
717 {
718 struct elf_x86_link_hash_table *htab
719 = (struct elf_x86_link_hash_table *) obfd->link.hash;
720
721 if (htab->loc_hash_table)
722 htab_delete (htab->loc_hash_table);
723 if (htab->loc_hash_memory)
724 objalloc_free ((struct objalloc *) htab->loc_hash_memory);
725 _bfd_elf_link_hash_table_free (obfd);
726 }
727
728 static bfd_boolean
729 elf_i386_is_reloc_section (const char *secname)
730 {
731 return CONST_STRNEQ (secname, ".rel");
732 }
733
734 #ifdef BFD64
735 static bfd_boolean
736 elf_x86_64_is_reloc_section (const char *secname)
737 {
738 return CONST_STRNEQ (secname, ".rela");
739 }
740 #endif
741
742 /* Create an x86 ELF linker hash table. */
743
744 struct bfd_link_hash_table *
745 _bfd_x86_elf_link_hash_table_create (bfd *abfd)
746 {
747 struct elf_x86_link_hash_table *ret;
748 const struct elf_backend_data *bed;
749 bfd_size_type amt = sizeof (struct elf_x86_link_hash_table);
750
751 ret = (struct elf_x86_link_hash_table *) bfd_zmalloc (amt);
752 if (ret == NULL)
753 return NULL;
754
755 bed = get_elf_backend_data (abfd);
756 if (!_bfd_elf_link_hash_table_init (&ret->elf, abfd,
757 _bfd_x86_elf_link_hash_newfunc,
758 sizeof (struct elf_x86_link_hash_entry),
759 bed->target_id))
760 {
761 free (ret);
762 return NULL;
763 }
764
765 #ifdef BFD64
766 /* NB: If BFD64 isn't defined, only i386 will be supported. */
767 if (bed->target_id == X86_64_ELF_DATA)
768 {
769 ret->convert_load = _bfd_x86_64_elf_convert_load;
770 ret->is_reloc_section = elf_x86_64_is_reloc_section;
771 ret->dt_reloc = DT_RELA;
772 ret->dt_reloc_sz = DT_RELASZ;
773 ret->dt_reloc_ent = DT_RELAENT;
774 ret->got_entry_size = 8;
775 ret->tls_get_addr = "__tls_get_addr";
776 }
777 if (ABI_64_P (abfd))
778 {
779 ret->r_info = elf64_r_info;
780 ret->r_sym = elf64_r_sym;
781 ret->sizeof_reloc = sizeof (Elf64_External_Rela);
782 ret->pointer_r_type = R_X86_64_64;
783 ret->dynamic_interpreter = ELF64_DYNAMIC_INTERPRETER;
784 ret->dynamic_interpreter_size = sizeof ELF64_DYNAMIC_INTERPRETER;
785 }
786 else
787 #endif
788 {
789 ret->r_info = elf32_r_info;
790 ret->r_sym = elf32_r_sym;
791 if (bed->target_id == X86_64_ELF_DATA)
792 {
793 ret->sizeof_reloc = sizeof (Elf32_External_Rela);
794 ret->pointer_r_type = R_X86_64_32;
795 ret->dynamic_interpreter = ELFX32_DYNAMIC_INTERPRETER;
796 ret->dynamic_interpreter_size
797 = sizeof ELFX32_DYNAMIC_INTERPRETER;
798 }
799 else
800 {
801 ret->convert_load = _bfd_i386_elf_convert_load;
802 ret->is_reloc_section = elf_i386_is_reloc_section;
803 ret->dt_reloc = DT_REL;
804 ret->dt_reloc_sz = DT_RELSZ;
805 ret->dt_reloc_ent = DT_RELENT;
806 ret->sizeof_reloc = sizeof (Elf32_External_Rel);
807 ret->got_entry_size = 4;
808 ret->pointer_r_type = R_386_32;
809 ret->dynamic_interpreter = ELF32_DYNAMIC_INTERPRETER;
810 ret->dynamic_interpreter_size
811 = sizeof ELF32_DYNAMIC_INTERPRETER;
812 ret->tls_get_addr = "___tls_get_addr";
813 }
814 }
815 ret->target_id = bed->target_id;
816
817 ret->loc_hash_table = htab_try_create (1024,
818 _bfd_x86_elf_local_htab_hash,
819 _bfd_x86_elf_local_htab_eq,
820 NULL);
821 ret->loc_hash_memory = objalloc_create ();
822 if (!ret->loc_hash_table || !ret->loc_hash_memory)
823 {
824 elf_x86_link_hash_table_free (abfd);
825 return NULL;
826 }
827 ret->elf.root.hash_table_free = elf_x86_link_hash_table_free;
828
829 return &ret->elf.root;
830 }
831
832 /* Sort relocs into address order. */
833
834 int
835 _bfd_x86_elf_compare_relocs (const void *ap, const void *bp)
836 {
837 const arelent *a = * (const arelent **) ap;
838 const arelent *b = * (const arelent **) bp;
839
840 if (a->address > b->address)
841 return 1;
842 else if (a->address < b->address)
843 return -1;
844 else
845 return 0;
846 }
847
848 bfd_boolean
849 _bfd_x86_elf_link_check_relocs (bfd *abfd, struct bfd_link_info *info)
850 {
851 if (!bfd_link_relocatable (info))
852 {
853 /* Check for __tls_get_addr reference. */
854 struct elf_x86_link_hash_table *htab;
855 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
856 htab = elf_x86_hash_table (info, bed->target_id);
857 if (htab)
858 {
859 struct elf_link_hash_entry *h
860 = elf_link_hash_lookup (elf_hash_table (info),
861 htab->tls_get_addr,
862 FALSE, FALSE, FALSE);
863 if (h != NULL)
864 ((struct elf_x86_link_hash_entry *) h)->tls_get_addr = 1;
865 }
866 }
867
868 /* Invoke the regular ELF backend linker to do all the work. */
869 return _bfd_elf_link_check_relocs (abfd, info);
870 }
871
872 /* Set the sizes of the dynamic sections. */
873
874 bfd_boolean
875 _bfd_x86_elf_size_dynamic_sections (bfd *output_bfd,
876 struct bfd_link_info *info)
877 {
878 struct elf_x86_link_hash_table *htab;
879 bfd *dynobj;
880 asection *s;
881 bfd_boolean relocs;
882 bfd *ibfd;
883 const struct elf_backend_data *bed
884 = get_elf_backend_data (output_bfd);
885
886 htab = elf_x86_hash_table (info, bed->target_id);
887 if (htab == NULL)
888 return FALSE;
889 dynobj = htab->elf.dynobj;
890 if (dynobj == NULL)
891 abort ();
892
893 /* Set up .got offsets for local syms, and space for local dynamic
894 relocs. */
895 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
896 {
897 bfd_signed_vma *local_got;
898 bfd_signed_vma *end_local_got;
899 char *local_tls_type;
900 bfd_vma *local_tlsdesc_gotent;
901 bfd_size_type locsymcount;
902 Elf_Internal_Shdr *symtab_hdr;
903 asection *srel;
904
905 if (! is_x86_elf (ibfd, htab))
906 continue;
907
908 for (s = ibfd->sections; s != NULL; s = s->next)
909 {
910 struct elf_dyn_relocs *p;
911
912 if (!htab->convert_load (ibfd, s, info))
913 return FALSE;
914
915 for (p = ((struct elf_dyn_relocs *)
916 elf_section_data (s)->local_dynrel);
917 p != NULL;
918 p = p->next)
919 {
920 if (!bfd_is_abs_section (p->sec)
921 && bfd_is_abs_section (p->sec->output_section))
922 {
923 /* Input section has been discarded, either because
924 it is a copy of a linkonce section or due to
925 linker script /DISCARD/, so we'll be discarding
926 the relocs too. */
927 }
928 else if (htab->is_vxworks
929 && strcmp (p->sec->output_section->name,
930 ".tls_vars") == 0)
931 {
932 /* Relocations in vxworks .tls_vars sections are
933 handled specially by the loader. */
934 }
935 else if (p->count != 0)
936 {
937 srel = elf_section_data (p->sec)->sreloc;
938 srel->size += p->count * htab->sizeof_reloc;
939 if ((p->sec->output_section->flags & SEC_READONLY) != 0
940 && (info->flags & DF_TEXTREL) == 0)
941 {
942 info->flags |= DF_TEXTREL;
943 if ((info->warn_shared_textrel && bfd_link_pic (info))
944 || info->error_textrel)
945 /* xgettext:c-format */
946 info->callbacks->einfo (_("%P: %B: warning: relocation in readonly section `%A'\n"),
947 p->sec->owner, p->sec);
948 }
949 }
950 }
951 }
952
953 local_got = elf_local_got_refcounts (ibfd);
954 if (!local_got)
955 continue;
956
957 symtab_hdr = &elf_symtab_hdr (ibfd);
958 locsymcount = symtab_hdr->sh_info;
959 end_local_got = local_got + locsymcount;
960 local_tls_type = elf_x86_local_got_tls_type (ibfd);
961 local_tlsdesc_gotent = elf_x86_local_tlsdesc_gotent (ibfd);
962 s = htab->elf.sgot;
963 srel = htab->elf.srelgot;
964 for (; local_got < end_local_got;
965 ++local_got, ++local_tls_type, ++local_tlsdesc_gotent)
966 {
967 *local_tlsdesc_gotent = (bfd_vma) -1;
968 if (*local_got > 0)
969 {
970 if (GOT_TLS_GDESC_P (*local_tls_type))
971 {
972 *local_tlsdesc_gotent = htab->elf.sgotplt->size
973 - elf_x86_compute_jump_table_size (htab);
974 htab->elf.sgotplt->size += 2 * htab->got_entry_size;
975 *local_got = (bfd_vma) -2;
976 }
977 if (! GOT_TLS_GDESC_P (*local_tls_type)
978 || GOT_TLS_GD_P (*local_tls_type))
979 {
980 *local_got = s->size;
981 s->size += htab->got_entry_size;
982 if (GOT_TLS_GD_P (*local_tls_type)
983 || *local_tls_type == GOT_TLS_IE_BOTH)
984 s->size += htab->got_entry_size;
985 }
986 if (bfd_link_pic (info)
987 || GOT_TLS_GD_ANY_P (*local_tls_type)
988 || (*local_tls_type & GOT_TLS_IE))
989 {
990 if (*local_tls_type == GOT_TLS_IE_BOTH)
991 srel->size += 2 * htab->sizeof_reloc;
992 else if (GOT_TLS_GD_P (*local_tls_type)
993 || ! GOT_TLS_GDESC_P (*local_tls_type))
994 srel->size += htab->sizeof_reloc;
995 if (GOT_TLS_GDESC_P (*local_tls_type))
996 {
997 htab->elf.srelplt->size += htab->sizeof_reloc;
998 if (bed->target_id == X86_64_ELF_DATA)
999 htab->tlsdesc_plt = (bfd_vma) -1;
1000 }
1001 }
1002 }
1003 else
1004 *local_got = (bfd_vma) -1;
1005 }
1006 }
1007
1008 if (htab->tls_ld_or_ldm_got.refcount > 0)
1009 {
1010 /* Allocate 2 got entries and 1 dynamic reloc for R_386_TLS_LDM
1011 or R_X86_64_TLSLD relocs. */
1012 htab->tls_ld_or_ldm_got.offset = htab->elf.sgot->size;
1013 htab->elf.sgot->size += 2 * htab->got_entry_size;
1014 htab->elf.srelgot->size += htab->sizeof_reloc;
1015 }
1016 else
1017 htab->tls_ld_or_ldm_got.offset = -1;
1018
1019 /* Allocate global sym .plt and .got entries, and space for global
1020 sym dynamic relocs. */
1021 elf_link_hash_traverse (&htab->elf, elf_x86_allocate_dynrelocs,
1022 info);
1023
1024 /* Allocate .plt and .got entries, and space for local symbols. */
1025 htab_traverse (htab->loc_hash_table, elf_x86_allocate_local_dynreloc,
1026 info);
1027
1028 /* For every jump slot reserved in the sgotplt, reloc_count is
1029 incremented. However, when we reserve space for TLS descriptors,
1030 it's not incremented, so in order to compute the space reserved
1031 for them, it suffices to multiply the reloc count by the jump
1032 slot size.
1033
1034 PR ld/13302: We start next_irelative_index at the end of .rela.plt
1035 so that R_{386,X86_64}_IRELATIVE entries come last. */
1036 if (htab->elf.srelplt)
1037 {
1038 htab->next_tls_desc_index = htab->elf.srelplt->reloc_count;
1039 htab->sgotplt_jump_table_size
1040 = elf_x86_compute_jump_table_size (htab);
1041 htab->next_irelative_index = htab->elf.srelplt->reloc_count - 1;
1042 }
1043 else if (htab->elf.irelplt)
1044 htab->next_irelative_index = htab->elf.irelplt->reloc_count - 1;
1045
1046 if (htab->tlsdesc_plt)
1047 {
1048 /* NB: tlsdesc_plt is set only for x86-64. If we're not using
1049 lazy TLS relocations, don't generate the PLT and GOT entries
1050 they require. */
1051 if ((info->flags & DF_BIND_NOW))
1052 htab->tlsdesc_plt = 0;
1053 else
1054 {
1055 htab->tlsdesc_got = htab->elf.sgot->size;
1056 htab->elf.sgot->size += htab->got_entry_size;
1057 /* Reserve room for the initial entry.
1058 FIXME: we could probably do away with it in this case. */
1059 if (htab->elf.splt->size == 0)
1060 htab->elf.splt->size = htab->plt.plt_entry_size;
1061 htab->tlsdesc_plt = htab->elf.splt->size;
1062 htab->elf.splt->size += htab->plt.plt_entry_size;
1063 }
1064 }
1065
1066 if (htab->elf.sgotplt)
1067 {
1068 /* Don't allocate .got.plt section if there are no GOT nor PLT
1069 entries and there is no reference to _GLOBAL_OFFSET_TABLE_. */
1070 if ((htab->elf.hgot == NULL
1071 || !htab->elf.hgot->ref_regular_nonweak)
1072 && (htab->elf.sgotplt->size == bed->got_header_size)
1073 && (htab->elf.splt == NULL
1074 || htab->elf.splt->size == 0)
1075 && (htab->elf.sgot == NULL
1076 || htab->elf.sgot->size == 0)
1077 && (htab->elf.iplt == NULL
1078 || htab->elf.iplt->size == 0)
1079 && (htab->elf.igotplt == NULL
1080 || htab->elf.igotplt->size == 0))
1081 htab->elf.sgotplt->size = 0;
1082 }
1083
1084 if (_bfd_elf_eh_frame_present (info))
1085 {
1086 if (htab->plt_eh_frame != NULL
1087 && htab->elf.splt != NULL
1088 && htab->elf.splt->size != 0
1089 && !bfd_is_abs_section (htab->elf.splt->output_section))
1090 htab->plt_eh_frame->size = htab->plt.eh_frame_plt_size;
1091
1092 if (htab->plt_got_eh_frame != NULL
1093 && htab->plt_got != NULL
1094 && htab->plt_got->size != 0
1095 && !bfd_is_abs_section (htab->plt_got->output_section))
1096 htab->plt_got_eh_frame->size
1097 = htab->non_lazy_plt->eh_frame_plt_size;
1098
1099 /* Unwind info for the second PLT and .plt.got sections are
1100 identical. */
1101 if (htab->plt_second_eh_frame != NULL
1102 && htab->plt_second != NULL
1103 && htab->plt_second->size != 0
1104 && !bfd_is_abs_section (htab->plt_second->output_section))
1105 htab->plt_second_eh_frame->size
1106 = htab->non_lazy_plt->eh_frame_plt_size;
1107 }
1108
1109 /* We now have determined the sizes of the various dynamic sections.
1110 Allocate memory for them. */
1111 relocs = FALSE;
1112 for (s = dynobj->sections; s != NULL; s = s->next)
1113 {
1114 bfd_boolean strip_section = TRUE;
1115
1116 if ((s->flags & SEC_LINKER_CREATED) == 0)
1117 continue;
1118
1119 if (s == htab->elf.splt
1120 || s == htab->elf.sgot)
1121 {
1122 /* Strip this section if we don't need it; see the
1123 comment below. */
1124 /* We'd like to strip these sections if they aren't needed, but if
1125 we've exported dynamic symbols from them we must leave them.
1126 It's too late to tell BFD to get rid of the symbols. */
1127
1128 if (htab->elf.hplt != NULL)
1129 strip_section = FALSE;
1130 }
1131 else if (s == htab->elf.sgotplt
1132 || s == htab->elf.iplt
1133 || s == htab->elf.igotplt
1134 || s == htab->plt_second
1135 || s == htab->plt_got
1136 || s == htab->plt_eh_frame
1137 || s == htab->plt_got_eh_frame
1138 || s == htab->plt_second_eh_frame
1139 || s == htab->elf.sdynbss
1140 || s == htab->elf.sdynrelro)
1141 {
1142 /* Strip these too. */
1143 }
1144 else if (htab->is_reloc_section (bfd_get_section_name (dynobj, s)))
1145 {
1146 if (s->size != 0
1147 && s != htab->elf.srelplt
1148 && s != htab->srelplt2)
1149 relocs = TRUE;
1150
1151 /* We use the reloc_count field as a counter if we need
1152 to copy relocs into the output file. */
1153 if (s != htab->elf.srelplt)
1154 s->reloc_count = 0;
1155 }
1156 else
1157 {
1158 /* It's not one of our sections, so don't allocate space. */
1159 continue;
1160 }
1161
1162 if (s->size == 0)
1163 {
1164 /* If we don't need this section, strip it from the
1165 output file. This is mostly to handle .rel.bss and
1166 .rel.plt. We must create both sections in
1167 create_dynamic_sections, because they must be created
1168 before the linker maps input sections to output
1169 sections. The linker does that before
1170 adjust_dynamic_symbol is called, and it is that
1171 function which decides whether anything needs to go
1172 into these sections. */
1173 if (strip_section)
1174 s->flags |= SEC_EXCLUDE;
1175 continue;
1176 }
1177
1178 if ((s->flags & SEC_HAS_CONTENTS) == 0)
1179 continue;
1180
1181 /* Allocate memory for the section contents. We use bfd_zalloc
1182 here in case unused entries are not reclaimed before the
1183 section's contents are written out. This should not happen,
1184 but this way if it does, we get a R_386_NONE or R_X86_64_NONE
1185 reloc instead of garbage. */
1186 s->contents = (unsigned char *) bfd_zalloc (dynobj, s->size);
1187 if (s->contents == NULL)
1188 return FALSE;
1189 }
1190
1191 if (htab->plt_eh_frame != NULL
1192 && htab->plt_eh_frame->contents != NULL)
1193 {
1194 memcpy (htab->plt_eh_frame->contents,
1195 htab->plt.eh_frame_plt,
1196 htab->plt_eh_frame->size);
1197 bfd_put_32 (dynobj, htab->elf.splt->size,
1198 htab->plt_eh_frame->contents + PLT_FDE_LEN_OFFSET);
1199 }
1200
1201 if (htab->plt_got_eh_frame != NULL
1202 && htab->plt_got_eh_frame->contents != NULL)
1203 {
1204 memcpy (htab->plt_got_eh_frame->contents,
1205 htab->non_lazy_plt->eh_frame_plt,
1206 htab->plt_got_eh_frame->size);
1207 bfd_put_32 (dynobj, htab->plt_got->size,
1208 (htab->plt_got_eh_frame->contents
1209 + PLT_FDE_LEN_OFFSET));
1210 }
1211
1212 if (htab->plt_second_eh_frame != NULL
1213 && htab->plt_second_eh_frame->contents != NULL)
1214 {
1215 memcpy (htab->plt_second_eh_frame->contents,
1216 htab->non_lazy_plt->eh_frame_plt,
1217 htab->plt_second_eh_frame->size);
1218 bfd_put_32 (dynobj, htab->plt_second->size,
1219 (htab->plt_second_eh_frame->contents
1220 + PLT_FDE_LEN_OFFSET));
1221 }
1222
1223 if (htab->elf.dynamic_sections_created)
1224 {
1225 /* Add some entries to the .dynamic section. We fill in the
1226 values later, in elf_{i386,x86_64}_finish_dynamic_sections,
1227 but we must add the entries now so that we get the correct
1228 size for the .dynamic section. The DT_DEBUG entry is filled
1229 in by the dynamic linker and used by the debugger. */
1230 #define add_dynamic_entry(TAG, VAL) \
1231 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
1232
1233 if (bfd_link_executable (info))
1234 {
1235 if (!add_dynamic_entry (DT_DEBUG, 0))
1236 return FALSE;
1237 }
1238
1239 if (htab->elf.splt->size != 0)
1240 {
1241 /* DT_PLTGOT is used by prelink even if there is no PLT
1242 relocation. */
1243 if (!add_dynamic_entry (DT_PLTGOT, 0))
1244 return FALSE;
1245 }
1246
1247 if (htab->elf.srelplt->size != 0)
1248 {
1249 if (!add_dynamic_entry (DT_PLTRELSZ, 0)
1250 || !add_dynamic_entry (DT_PLTREL, htab->dt_reloc)
1251 || !add_dynamic_entry (DT_JMPREL, 0))
1252 return FALSE;
1253 }
1254
1255 if (htab->tlsdesc_plt
1256 && (!add_dynamic_entry (DT_TLSDESC_PLT, 0)
1257 || !add_dynamic_entry (DT_TLSDESC_GOT, 0)))
1258 return FALSE;
1259
1260 if (relocs)
1261 {
1262 if (!add_dynamic_entry (htab->dt_reloc, 0)
1263 || !add_dynamic_entry (htab->dt_reloc_sz, 0)
1264 || !add_dynamic_entry (htab->dt_reloc_ent,
1265 htab->sizeof_reloc))
1266 return FALSE;
1267
1268 /* If any dynamic relocs apply to a read-only section,
1269 then we need a DT_TEXTREL entry. */
1270 if ((info->flags & DF_TEXTREL) == 0)
1271 elf_link_hash_traverse (&htab->elf,
1272 _bfd_x86_elf_readonly_dynrelocs,
1273 info);
1274
1275 if ((info->flags & DF_TEXTREL) != 0)
1276 {
1277 if (htab->readonly_dynrelocs_against_ifunc)
1278 {
1279 info->callbacks->einfo
1280 (_("%P%X: read-only segment has dynamic IFUNC relocations; recompile with -fPIC\n"));
1281 bfd_set_error (bfd_error_bad_value);
1282 return FALSE;
1283 }
1284
1285 if (!add_dynamic_entry (DT_TEXTREL, 0))
1286 return FALSE;
1287 }
1288 }
1289 if (htab->is_vxworks
1290 && !elf_vxworks_add_dynamic_entries (output_bfd, info))
1291 return FALSE;
1292 }
1293 #undef add_dynamic_entry
1294
1295 return TRUE;
1296 }
1297
1298 bfd_boolean
1299 _bfd_x86_elf_always_size_sections (bfd *output_bfd,
1300 struct bfd_link_info *info)
1301 {
1302 asection *tls_sec = elf_hash_table (info)->tls_sec;
1303
1304 if (tls_sec)
1305 {
1306 struct elf_link_hash_entry *tlsbase;
1307
1308 tlsbase = elf_link_hash_lookup (elf_hash_table (info),
1309 "_TLS_MODULE_BASE_",
1310 FALSE, FALSE, FALSE);
1311
1312 if (tlsbase && tlsbase->type == STT_TLS)
1313 {
1314 struct elf_x86_link_hash_table *htab;
1315 struct bfd_link_hash_entry *bh = NULL;
1316 const struct elf_backend_data *bed
1317 = get_elf_backend_data (output_bfd);
1318
1319 htab = elf_x86_hash_table (info, bed->target_id);
1320 if (htab == NULL)
1321 return FALSE;
1322
1323 if (!(_bfd_generic_link_add_one_symbol
1324 (info, output_bfd, "_TLS_MODULE_BASE_", BSF_LOCAL,
1325 tls_sec, 0, NULL, FALSE,
1326 bed->collect, &bh)))
1327 return FALSE;
1328
1329 htab->tls_module_base = bh;
1330
1331 tlsbase = (struct elf_link_hash_entry *)bh;
1332 tlsbase->def_regular = 1;
1333 tlsbase->other = STV_HIDDEN;
1334 tlsbase->root.linker_def = 1;
1335 (*bed->elf_backend_hide_symbol) (info, tlsbase, TRUE);
1336 }
1337 }
1338
1339 return TRUE;
1340 }
1341
1342 void
1343 _bfd_x86_elf_merge_symbol_attribute (struct elf_link_hash_entry *h,
1344 const Elf_Internal_Sym *isym,
1345 bfd_boolean definition,
1346 bfd_boolean dynamic ATTRIBUTE_UNUSED)
1347 {
1348 if (definition)
1349 {
1350 struct elf_x86_link_hash_entry *eh
1351 = (struct elf_x86_link_hash_entry *) h;
1352 eh->def_protected = (ELF_ST_VISIBILITY (isym->st_other)
1353 == STV_PROTECTED);
1354 }
1355 }
1356
1357 /* Copy the extra info we tack onto an elf_link_hash_entry. */
1358
1359 void
1360 _bfd_x86_elf_copy_indirect_symbol (struct bfd_link_info *info,
1361 struct elf_link_hash_entry *dir,
1362 struct elf_link_hash_entry *ind)
1363 {
1364 struct elf_x86_link_hash_entry *edir, *eind;
1365
1366 edir = (struct elf_x86_link_hash_entry *) dir;
1367 eind = (struct elf_x86_link_hash_entry *) ind;
1368
1369 if (eind->dyn_relocs != NULL)
1370 {
1371 if (edir->dyn_relocs != NULL)
1372 {
1373 struct elf_dyn_relocs **pp;
1374 struct elf_dyn_relocs *p;
1375
1376 /* Add reloc counts against the indirect sym to the direct sym
1377 list. Merge any entries against the same section. */
1378 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
1379 {
1380 struct elf_dyn_relocs *q;
1381
1382 for (q = edir->dyn_relocs; q != NULL; q = q->next)
1383 if (q->sec == p->sec)
1384 {
1385 q->pc_count += p->pc_count;
1386 q->count += p->count;
1387 *pp = p->next;
1388 break;
1389 }
1390 if (q == NULL)
1391 pp = &p->next;
1392 }
1393 *pp = edir->dyn_relocs;
1394 }
1395
1396 edir->dyn_relocs = eind->dyn_relocs;
1397 eind->dyn_relocs = NULL;
1398 }
1399
1400 if (ind->root.type == bfd_link_hash_indirect
1401 && dir->got.refcount <= 0)
1402 {
1403 edir->tls_type = eind->tls_type;
1404 eind->tls_type = GOT_UNKNOWN;
1405 }
1406
1407 /* Copy gotoff_ref so that elf_i386_adjust_dynamic_symbol will
1408 generate a R_386_COPY reloc. */
1409 edir->gotoff_ref |= eind->gotoff_ref;
1410
1411 edir->has_got_reloc |= eind->has_got_reloc;
1412 edir->has_non_got_reloc |= eind->has_non_got_reloc;
1413
1414 if (ELIMINATE_COPY_RELOCS
1415 && ind->root.type != bfd_link_hash_indirect
1416 && dir->dynamic_adjusted)
1417 {
1418 /* If called to transfer flags for a weakdef during processing
1419 of elf_adjust_dynamic_symbol, don't copy non_got_ref.
1420 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
1421 if (dir->versioned != versioned_hidden)
1422 dir->ref_dynamic |= ind->ref_dynamic;
1423 dir->ref_regular |= ind->ref_regular;
1424 dir->ref_regular_nonweak |= ind->ref_regular_nonweak;
1425 dir->needs_plt |= ind->needs_plt;
1426 dir->pointer_equality_needed |= ind->pointer_equality_needed;
1427 }
1428 else
1429 {
1430 if (eind->func_pointer_refcount > 0)
1431 {
1432 edir->func_pointer_refcount += eind->func_pointer_refcount;
1433 eind->func_pointer_refcount = 0;
1434 }
1435
1436 _bfd_elf_link_hash_copy_indirect (info, dir, ind);
1437 }
1438 }
1439
1440 /* Remove undefined weak symbol from the dynamic symbol table if it
1441 is resolved to 0. */
1442
1443 bfd_boolean
1444 _bfd_x86_elf_fixup_symbol (struct bfd_link_info *info,
1445 struct elf_link_hash_entry *h)
1446 {
1447 if (h->dynindx != -1)
1448 {
1449 const struct elf_backend_data *bed
1450 = get_elf_backend_data (info->output_bfd);
1451 if (UNDEFINED_WEAK_RESOLVED_TO_ZERO (info,
1452 bed->target_id,
1453 elf_x86_hash_entry (h)->has_got_reloc,
1454 elf_x86_hash_entry (h)))
1455 {
1456 h->dynindx = -1;
1457 _bfd_elf_strtab_delref (elf_hash_table (info)->dynstr,
1458 h->dynstr_index);
1459 }
1460 }
1461 return TRUE;
1462 }
1463
1464 /* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */
1465
1466 bfd_boolean
1467 _bfd_x86_elf_hash_symbol (struct elf_link_hash_entry *h)
1468 {
1469 if (h->plt.offset != (bfd_vma) -1
1470 && !h->def_regular
1471 && !h->pointer_equality_needed)
1472 return FALSE;
1473
1474 return _bfd_elf_hash_symbol (h);
1475 }
1476
1477 /* Adjust a symbol defined by a dynamic object and referenced by a
1478 regular object. The current definition is in some section of the
1479 dynamic object, but we're not including those sections. We have to
1480 change the definition to something the rest of the link can
1481 understand. */
1482
1483 bfd_boolean
1484 _bfd_x86_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
1485 struct elf_link_hash_entry *h)
1486 {
1487 struct elf_x86_link_hash_table *htab;
1488 asection *s, *srel;
1489 struct elf_x86_link_hash_entry *eh;
1490 struct elf_dyn_relocs *p;
1491 const struct elf_backend_data *bed
1492 = get_elf_backend_data (info->output_bfd);
1493
1494 /* STT_GNU_IFUNC symbol must go through PLT. */
1495 if (h->type == STT_GNU_IFUNC)
1496 {
1497 /* All local STT_GNU_IFUNC references must be treate as local
1498 calls via local PLT. */
1499 if (h->ref_regular
1500 && SYMBOL_CALLS_LOCAL (info, h))
1501 {
1502 bfd_size_type pc_count = 0, count = 0;
1503 struct elf_dyn_relocs **pp;
1504
1505 eh = (struct elf_x86_link_hash_entry *) h;
1506 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1507 {
1508 pc_count += p->pc_count;
1509 p->count -= p->pc_count;
1510 p->pc_count = 0;
1511 count += p->count;
1512 if (p->count == 0)
1513 *pp = p->next;
1514 else
1515 pp = &p->next;
1516 }
1517
1518 if (pc_count || count)
1519 {
1520 h->non_got_ref = 1;
1521 if (pc_count)
1522 {
1523 /* Increment PLT reference count only for PC-relative
1524 references. */
1525 h->needs_plt = 1;
1526 if (h->plt.refcount <= 0)
1527 h->plt.refcount = 1;
1528 else
1529 h->plt.refcount += 1;
1530 }
1531 }
1532 }
1533
1534 if (h->plt.refcount <= 0)
1535 {
1536 h->plt.offset = (bfd_vma) -1;
1537 h->needs_plt = 0;
1538 }
1539 return TRUE;
1540 }
1541
1542 /* If this is a function, put it in the procedure linkage table. We
1543 will fill in the contents of the procedure linkage table later,
1544 when we know the address of the .got section. */
1545 if (h->type == STT_FUNC
1546 || h->needs_plt)
1547 {
1548 if (h->plt.refcount <= 0
1549 || SYMBOL_CALLS_LOCAL (info, h)
1550 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1551 && h->root.type == bfd_link_hash_undefweak))
1552 {
1553 /* This case can occur if we saw a PLT32 reloc in an input
1554 file, but the symbol was never referred to by a dynamic
1555 object, or if all references were garbage collected. In
1556 such a case, we don't actually need to build a procedure
1557 linkage table, and we can just do a PC32 reloc instead. */
1558 h->plt.offset = (bfd_vma) -1;
1559 h->needs_plt = 0;
1560 }
1561
1562 return TRUE;
1563 }
1564 else
1565 /* It's possible that we incorrectly decided a .plt reloc was needed
1566 * for an R_386_PC32/R_X86_64_PC32 reloc to a non-function sym in
1567 check_relocs. We can't decide accurately between function and
1568 non-function syms in check-relocs; Objects loaded later in
1569 the link may change h->type. So fix it now. */
1570 h->plt.offset = (bfd_vma) -1;
1571
1572 eh = (struct elf_x86_link_hash_entry *) h;
1573
1574 /* If this is a weak symbol, and there is a real definition, the
1575 processor independent code will have arranged for us to see the
1576 real definition first, and we can just use the same value. */
1577 if (h->u.weakdef != NULL)
1578 {
1579 BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined
1580 || h->u.weakdef->root.type == bfd_link_hash_defweak);
1581 h->root.u.def.section = h->u.weakdef->root.u.def.section;
1582 h->root.u.def.value = h->u.weakdef->root.u.def.value;
1583 if (ELIMINATE_COPY_RELOCS
1584 || info->nocopyreloc
1585 || SYMBOL_NO_COPYRELOC (info, eh))
1586 {
1587 /* NB: needs_copy is always 0 for i386. */
1588 h->non_got_ref = h->u.weakdef->non_got_ref;
1589 eh->needs_copy = h->u.weakdef->needs_copy;
1590 }
1591 return TRUE;
1592 }
1593
1594 /* This is a reference to a symbol defined by a dynamic object which
1595 is not a function. */
1596
1597 /* If we are creating a shared library, we must presume that the
1598 only references to the symbol are via the global offset table.
1599 For such cases we need not do anything here; the relocations will
1600 be handled correctly by relocate_section. */
1601 if (!bfd_link_executable (info))
1602 return TRUE;
1603
1604 /* If there are no references to this symbol that do not use the
1605 GOT nor R_386_GOTOFF relocation, we don't need to generate a copy
1606 reloc. NB: gotoff_ref is always 0 for x86-64. */
1607 if (!h->non_got_ref && !eh->gotoff_ref)
1608 return TRUE;
1609
1610 /* If -z nocopyreloc was given, we won't generate them either. */
1611 if (info->nocopyreloc || SYMBOL_NO_COPYRELOC (info, eh))
1612 {
1613 h->non_got_ref = 0;
1614 return TRUE;
1615 }
1616
1617 htab = elf_x86_hash_table (info, bed->target_id);
1618 if (htab == NULL)
1619 return FALSE;
1620
1621 /* If there aren't any dynamic relocs in read-only sections nor
1622 R_386_GOTOFF relocation, then we can keep the dynamic relocs and
1623 avoid the copy reloc. This doesn't work on VxWorks, where we can
1624 not have dynamic relocations (other than copy and jump slot
1625 relocations) in an executable. */
1626 if (ELIMINATE_COPY_RELOCS
1627 && (bed->target_id == X86_64_ELF_DATA
1628 || (!eh->gotoff_ref
1629 && !htab->is_vxworks)))
1630 {
1631 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1632 {
1633 s = p->sec->output_section;
1634 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1635 break;
1636 }
1637
1638 /* If we didn't find any dynamic relocs in read-only sections,
1639 then we'll be keeping the dynamic relocs and avoiding the copy
1640 reloc. */
1641 if (p == NULL)
1642 {
1643 h->non_got_ref = 0;
1644 return TRUE;
1645 }
1646 }
1647
1648 /* We must allocate the symbol in our .dynbss section, which will
1649 become part of the .bss section of the executable. There will be
1650 an entry for this symbol in the .dynsym section. The dynamic
1651 object will contain position independent code, so all references
1652 from the dynamic object to this symbol will go through the global
1653 offset table. The dynamic linker will use the .dynsym entry to
1654 determine the address it must put in the global offset table, so
1655 both the dynamic object and the regular object will refer to the
1656 same memory location for the variable. */
1657
1658 /* We must generate a R_386_COPY/R_X86_64_COPY reloc to tell the
1659 dynamic linker to copy the initial value out of the dynamic object
1660 and into the runtime process image. */
1661 if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
1662 {
1663 s = htab->elf.sdynrelro;
1664 srel = htab->elf.sreldynrelro;
1665 }
1666 else
1667 {
1668 s = htab->elf.sdynbss;
1669 srel = htab->elf.srelbss;
1670 }
1671 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
1672 {
1673 srel->size += htab->sizeof_reloc;
1674 h->needs_copy = 1;
1675 }
1676
1677 return _bfd_elf_adjust_dynamic_copy (info, h, s);
1678 }
1679
1680 /* Return the section that should be marked against GC for a given
1681 relocation. */
1682
1683 asection *
1684 _bfd_x86_elf_gc_mark_hook (asection *sec,
1685 struct bfd_link_info *info,
1686 Elf_Internal_Rela *rel,
1687 struct elf_link_hash_entry *h,
1688 Elf_Internal_Sym *sym)
1689 {
1690 /* Compiler should optimize this out. */
1691 if (((unsigned int) R_X86_64_GNU_VTINHERIT
1692 != (unsigned int) R_386_GNU_VTINHERIT)
1693 || ((unsigned int) R_X86_64_GNU_VTENTRY
1694 != (unsigned int) R_386_GNU_VTENTRY))
1695 abort ();
1696
1697 if (h != NULL)
1698 switch (ELF32_R_TYPE (rel->r_info))
1699 {
1700 case R_X86_64_GNU_VTINHERIT:
1701 case R_X86_64_GNU_VTENTRY:
1702 return NULL;
1703 }
1704
1705 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
1706 }
1707
1708 static bfd_vma
1709 elf_i386_get_plt_got_vma (struct elf_x86_plt *plt_p ATTRIBUTE_UNUSED,
1710 bfd_vma off,
1711 bfd_vma offset ATTRIBUTE_UNUSED,
1712 bfd_vma got_addr)
1713 {
1714 return got_addr + off;
1715 }
1716
1717 static bfd_vma
1718 elf_x86_64_get_plt_got_vma (struct elf_x86_plt *plt_p,
1719 bfd_vma off,
1720 bfd_vma offset,
1721 bfd_vma got_addr ATTRIBUTE_UNUSED)
1722 {
1723 return plt_p->sec->vma + offset + off + plt_p->plt_got_insn_size;
1724 }
1725
1726 static bfd_boolean
1727 elf_i386_valid_plt_reloc_p (unsigned int type)
1728 {
1729 return (type == R_386_JUMP_SLOT
1730 || type == R_386_GLOB_DAT
1731 || type == R_386_IRELATIVE);
1732 }
1733
1734 static bfd_boolean
1735 elf_x86_64_valid_plt_reloc_p (unsigned int type)
1736 {
1737 return (type == R_X86_64_JUMP_SLOT
1738 || type == R_X86_64_GLOB_DAT
1739 || type == R_X86_64_IRELATIVE);
1740 }
1741
1742 long
1743 _bfd_x86_elf_get_synthetic_symtab (bfd *abfd,
1744 long count,
1745 long relsize,
1746 bfd_vma got_addr,
1747 struct elf_x86_plt plts[],
1748 asymbol **dynsyms,
1749 asymbol **ret)
1750 {
1751 long size, i, n, len;
1752 int j;
1753 unsigned int plt_got_offset, plt_entry_size;
1754 asymbol *s;
1755 bfd_byte *plt_contents;
1756 long dynrelcount;
1757 arelent **dynrelbuf, *p;
1758 char *names;
1759 const struct elf_backend_data *bed;
1760 bfd_vma (*get_plt_got_vma) (struct elf_x86_plt *, bfd_vma, bfd_vma,
1761 bfd_vma);
1762 bfd_boolean (*valid_plt_reloc_p) (unsigned int);
1763
1764 if (count == 0)
1765 return -1;
1766
1767 dynrelbuf = (arelent **) bfd_malloc (relsize);
1768 if (dynrelbuf == NULL)
1769 return -1;
1770
1771 dynrelcount = bfd_canonicalize_dynamic_reloc (abfd, dynrelbuf,
1772 dynsyms);
1773
1774 /* Sort the relocs by address. */
1775 qsort (dynrelbuf, dynrelcount, sizeof (arelent *),
1776 _bfd_x86_elf_compare_relocs);
1777
1778 size = count * sizeof (asymbol);
1779
1780 /* Allocate space for @plt suffixes. */
1781 n = 0;
1782 for (i = 0; i < dynrelcount; i++)
1783 {
1784 p = dynrelbuf[i];
1785 size += strlen ((*p->sym_ptr_ptr)->name) + sizeof ("@plt");
1786 if (p->addend != 0)
1787 size += sizeof ("+0x") - 1 + 8 + 8 * ABI_64_P (abfd);
1788 }
1789
1790 s = *ret = (asymbol *) bfd_zmalloc (size);
1791 if (s == NULL)
1792 goto bad_return;
1793
1794 bed = get_elf_backend_data (abfd);
1795
1796 if (bed->target_id == X86_64_ELF_DATA)
1797 {
1798 get_plt_got_vma = elf_x86_64_get_plt_got_vma;
1799 valid_plt_reloc_p = elf_x86_64_valid_plt_reloc_p;
1800 }
1801 else
1802 {
1803 get_plt_got_vma = elf_i386_get_plt_got_vma;
1804 valid_plt_reloc_p = elf_i386_valid_plt_reloc_p;
1805 if (got_addr)
1806 {
1807 /* Check .got.plt and then .got to get the _GLOBAL_OFFSET_TABLE_
1808 address. */
1809 asection *sec = bfd_get_section_by_name (abfd, ".got.plt");
1810 if (sec != NULL)
1811 got_addr = sec->vma;
1812 else
1813 {
1814 sec = bfd_get_section_by_name (abfd, ".got");
1815 if (sec != NULL)
1816 got_addr = sec->vma;
1817 }
1818
1819 if (got_addr == (bfd_vma) -1)
1820 goto bad_return;
1821 }
1822 }
1823
1824 /* Check for each PLT section. */
1825 names = (char *) (s + count);
1826 size = 0;
1827 n = 0;
1828 for (j = 0; plts[j].name != NULL; j++)
1829 if ((plt_contents = plts[j].contents) != NULL)
1830 {
1831 long k;
1832 bfd_vma offset;
1833 asection *plt;
1834 struct elf_x86_plt *plt_p = &plts[j];
1835
1836 plt_got_offset = plt_p->plt_got_offset;
1837 plt_entry_size = plt_p->plt_entry_size;
1838
1839 plt = plt_p->sec;
1840
1841 if ((plt_p->type & plt_lazy))
1842 {
1843 /* Skip PLT0 in lazy PLT. */
1844 k = 1;
1845 offset = plt_entry_size;
1846 }
1847 else
1848 {
1849 k = 0;
1850 offset = 0;
1851 }
1852
1853 /* Check each PLT entry against dynamic relocations. */
1854 for (; k < plt_p->count; k++)
1855 {
1856 int off;
1857 bfd_vma got_vma;
1858 long min, max, mid;
1859
1860 /* Get the GOT offset for i386 or the PC-relative offset
1861 for x86-64, a signed 32-bit integer. */
1862 off = H_GET_32 (abfd, (plt_contents + offset
1863 + plt_got_offset));
1864 got_vma = get_plt_got_vma (plt_p, off, offset, got_addr);
1865
1866 /* Binary search. */
1867 p = dynrelbuf[0];
1868 min = 0;
1869 max = dynrelcount;
1870 while ((min + 1) < max)
1871 {
1872 arelent *r;
1873
1874 mid = (min + max) / 2;
1875 r = dynrelbuf[mid];
1876 if (got_vma > r->address)
1877 min = mid;
1878 else if (got_vma < r->address)
1879 max = mid;
1880 else
1881 {
1882 p = r;
1883 break;
1884 }
1885 }
1886
1887 /* Skip unknown relocation. PR 17512: file: bc9d6cf5. */
1888 if (got_vma == p->address
1889 && p->howto != NULL
1890 && valid_plt_reloc_p (p->howto->type))
1891 {
1892 *s = **p->sym_ptr_ptr;
1893 /* Undefined syms won't have BSF_LOCAL or BSF_GLOBAL
1894 set. Since we are defining a symbol, ensure one
1895 of them is set. */
1896 if ((s->flags & BSF_LOCAL) == 0)
1897 s->flags |= BSF_GLOBAL;
1898 s->flags |= BSF_SYNTHETIC;
1899 /* This is no longer a section symbol. */
1900 s->flags &= ~BSF_SECTION_SYM;
1901 s->section = plt;
1902 s->the_bfd = plt->owner;
1903 s->value = offset;
1904 s->udata.p = NULL;
1905 s->name = names;
1906 len = strlen ((*p->sym_ptr_ptr)->name);
1907 memcpy (names, (*p->sym_ptr_ptr)->name, len);
1908 names += len;
1909 if (p->addend != 0)
1910 {
1911 char buf[30], *a;
1912
1913 memcpy (names, "+0x", sizeof ("+0x") - 1);
1914 names += sizeof ("+0x") - 1;
1915 bfd_sprintf_vma (abfd, buf, p->addend);
1916 for (a = buf; *a == '0'; ++a)
1917 ;
1918 size = strlen (a);
1919 memcpy (names, a, size);
1920 names += size;
1921 }
1922 memcpy (names, "@plt", sizeof ("@plt"));
1923 names += sizeof ("@plt");
1924 n++;
1925 s++;
1926 }
1927 offset += plt_entry_size;
1928 }
1929 }
1930
1931 /* PLT entries with R_386_TLS_DESC relocations are skipped. */
1932 if (n == 0)
1933 {
1934 bad_return:
1935 count = -1;
1936 }
1937 else
1938 count = n;
1939
1940 for (j = 0; plts[j].name != NULL; j++)
1941 if (plts[j].contents != NULL)
1942 free (plts[j].contents);
1943
1944 free (dynrelbuf);
1945
1946 return count;
1947 }
1948
1949 /* Parse x86 GNU properties. */
1950
1951 enum elf_property_kind
1952 _bfd_x86_elf_parse_gnu_properties (bfd *abfd, unsigned int type,
1953 bfd_byte *ptr, unsigned int datasz)
1954 {
1955 elf_property *prop;
1956
1957 switch (type)
1958 {
1959 case GNU_PROPERTY_X86_ISA_1_USED:
1960 case GNU_PROPERTY_X86_ISA_1_NEEDED:
1961 case GNU_PROPERTY_X86_FEATURE_1_AND:
1962 if (datasz != 4)
1963 {
1964 _bfd_error_handler
1965 ((type == GNU_PROPERTY_X86_ISA_1_USED
1966 ? _("error: %B: <corrupt x86 ISA used size: 0x%x>")
1967 : (type == GNU_PROPERTY_X86_ISA_1_NEEDED
1968 ? _("error: %B: <corrupt x86 ISA needed size: 0x%x>")
1969 : _("error: %B: <corrupt x86 feature size: 0x%x>"))),
1970 abfd, datasz);
1971 return property_corrupt;
1972 }
1973 prop = _bfd_elf_get_property (abfd, type, datasz);
1974 /* Combine properties of the same type. */
1975 prop->u.number |= bfd_h_get_32 (abfd, ptr);
1976 prop->pr_kind = property_number;
1977 break;
1978
1979 default:
1980 return property_ignored;
1981 }
1982
1983 return property_number;
1984 }
1985
1986 /* Merge x86 GNU property BPROP with APROP. If APROP isn't NULL,
1987 return TRUE if APROP is updated. Otherwise, return TRUE if BPROP
1988 should be merged with ABFD. */
1989
1990 bfd_boolean
1991 _bfd_x86_elf_merge_gnu_properties (struct bfd_link_info *info,
1992 bfd *abfd ATTRIBUTE_UNUSED,
1993 elf_property *aprop,
1994 elf_property *bprop)
1995 {
1996 unsigned int number, features;
1997 bfd_boolean updated = FALSE;
1998 unsigned int pr_type = aprop != NULL ? aprop->pr_type : bprop->pr_type;
1999
2000 switch (pr_type)
2001 {
2002 case GNU_PROPERTY_X86_ISA_1_USED:
2003 case GNU_PROPERTY_X86_ISA_1_NEEDED:
2004 if (aprop != NULL && bprop != NULL)
2005 {
2006 number = aprop->u.number;
2007 aprop->u.number = number | bprop->u.number;
2008 updated = number != (unsigned int) aprop->u.number;
2009 }
2010 else
2011 {
2012 /* Return TRUE if APROP is NULL to indicate that BPROP should
2013 be added to ABFD. */
2014 updated = aprop == NULL;
2015 }
2016 break;
2017
2018 case GNU_PROPERTY_X86_FEATURE_1_AND:
2019 /* Only one of APROP and BPROP can be NULL:
2020 1. APROP & BPROP when both APROP and BPROP aren't NULL.
2021 2. If APROP is NULL, remove x86 feature.
2022 3. Otherwise, do nothing.
2023 */
2024 if (aprop != NULL && bprop != NULL)
2025 {
2026 features = 0;
2027 if (info->ibt)
2028 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2029 if (info->shstk)
2030 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2031 number = aprop->u.number;
2032 /* Add GNU_PROPERTY_X86_FEATURE_1_IBT and
2033 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2034 aprop->u.number = (number & bprop->u.number) | features;
2035 updated = number != (unsigned int) aprop->u.number;
2036 /* Remove the property if all feature bits are cleared. */
2037 if (aprop->u.number == 0)
2038 aprop->pr_kind = property_remove;
2039 }
2040 else
2041 {
2042 features = 0;
2043 if (info->ibt)
2044 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2045 if (info->shstk)
2046 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2047 if (features)
2048 {
2049 /* Add GNU_PROPERTY_X86_FEATURE_1_IBT and
2050 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2051 if (aprop != NULL)
2052 {
2053 number = aprop->u.number;
2054 aprop->u.number = number | features;
2055 updated = number != (unsigned int) aprop->u.number;
2056 }
2057 else
2058 {
2059 bprop->u.number |= features;
2060 updated = TRUE;
2061 }
2062 }
2063 else if (aprop != NULL)
2064 {
2065 aprop->pr_kind = property_remove;
2066 updated = TRUE;
2067 }
2068 }
2069 break;
2070
2071 default:
2072 /* Never should happen. */
2073 abort ();
2074 }
2075
2076 return updated;
2077 }
2078
2079 /* Set up x86 GNU properties. Return the first relocatable ELF input
2080 with GNU properties if found. Otherwise, return NULL. */
2081
2082 bfd *
2083 _bfd_x86_elf_link_setup_gnu_properties
2084 (struct bfd_link_info *info,
2085 struct elf_x86_plt_layout_table *plt_layout)
2086 {
2087 bfd_boolean normal_target;
2088 bfd_boolean lazy_plt;
2089 asection *sec, *pltsec;
2090 bfd *dynobj;
2091 bfd_boolean use_ibt_plt;
2092 unsigned int plt_alignment, features;
2093 struct elf_x86_link_hash_table *htab;
2094 bfd *pbfd;
2095 bfd *ebfd = NULL;
2096 elf_property *prop;
2097 const struct elf_backend_data *bed;
2098 unsigned int class_align = ABI_64_P (info->output_bfd) ? 3 : 2;
2099 unsigned int got_align;
2100
2101 features = 0;
2102 if (info->ibt)
2103 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2104 if (info->shstk)
2105 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2106
2107 /* Find a normal input file with GNU property note. */
2108 for (pbfd = info->input_bfds;
2109 pbfd != NULL;
2110 pbfd = pbfd->link.next)
2111 if (bfd_get_flavour (pbfd) == bfd_target_elf_flavour
2112 && bfd_count_sections (pbfd) != 0)
2113 {
2114 ebfd = pbfd;
2115
2116 if (elf_properties (pbfd) != NULL)
2117 break;
2118 }
2119
2120 if (ebfd != NULL && features)
2121 {
2122 /* If features is set, add GNU_PROPERTY_X86_FEATURE_1_IBT and
2123 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2124 prop = _bfd_elf_get_property (ebfd,
2125 GNU_PROPERTY_X86_FEATURE_1_AND,
2126 4);
2127 prop->u.number |= features;
2128 prop->pr_kind = property_number;
2129
2130 /* Create the GNU property note section if needed. */
2131 if (pbfd == NULL)
2132 {
2133 sec = bfd_make_section_with_flags (ebfd,
2134 NOTE_GNU_PROPERTY_SECTION_NAME,
2135 (SEC_ALLOC
2136 | SEC_LOAD
2137 | SEC_IN_MEMORY
2138 | SEC_READONLY
2139 | SEC_HAS_CONTENTS
2140 | SEC_DATA));
2141 if (sec == NULL)
2142 info->callbacks->einfo (_("%F: failed to create GNU property section\n"));
2143
2144 if (!bfd_set_section_alignment (ebfd, sec, class_align))
2145 {
2146 error_alignment:
2147 info->callbacks->einfo (_("%F%A: failed to align section\n"),
2148 sec);
2149 }
2150
2151 elf_section_type (sec) = SHT_NOTE;
2152 }
2153 }
2154
2155 pbfd = _bfd_elf_link_setup_gnu_properties (info);
2156
2157 if (bfd_link_relocatable (info))
2158 return pbfd;
2159
2160 bed = get_elf_backend_data (info->output_bfd);
2161
2162 htab = elf_x86_hash_table (info, bed->target_id);
2163 if (htab == NULL)
2164 return pbfd;
2165
2166 htab->is_vxworks = plt_layout->is_vxworks;
2167
2168 use_ibt_plt = info->ibtplt || info->ibt;
2169 if (!use_ibt_plt && pbfd != NULL)
2170 {
2171 /* Check if GNU_PROPERTY_X86_FEATURE_1_IBT is on. */
2172 elf_property_list *p;
2173
2174 /* The property list is sorted in order of type. */
2175 for (p = elf_properties (pbfd); p; p = p->next)
2176 {
2177 if (GNU_PROPERTY_X86_FEATURE_1_AND == p->property.pr_type)
2178 {
2179 use_ibt_plt = !!(p->property.u.number
2180 & GNU_PROPERTY_X86_FEATURE_1_IBT);
2181 break;
2182 }
2183 else if (GNU_PROPERTY_X86_FEATURE_1_AND < p->property.pr_type)
2184 break;
2185 }
2186 }
2187
2188 dynobj = htab->elf.dynobj;
2189
2190 /* Set htab->elf.dynobj here so that there is no need to check and
2191 set it in check_relocs. */
2192 if (dynobj == NULL)
2193 {
2194 if (pbfd != NULL)
2195 {
2196 htab->elf.dynobj = pbfd;
2197 dynobj = pbfd;
2198 }
2199 else
2200 {
2201 bfd *abfd;
2202
2203 /* Find a normal input file to hold linker created
2204 sections. */
2205 for (abfd = info->input_bfds;
2206 abfd != NULL;
2207 abfd = abfd->link.next)
2208 if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
2209 && (abfd->flags
2210 & (DYNAMIC | BFD_LINKER_CREATED | BFD_PLUGIN)) == 0)
2211 {
2212 htab->elf.dynobj = abfd;
2213 dynobj = abfd;
2214 break;
2215 }
2216 }
2217 }
2218
2219 /* Even when lazy binding is disabled by "-z now", the PLT0 entry may
2220 still be used with LD_AUDIT or LD_PROFILE if PLT entry is used for
2221 canonical function address. */
2222 htab->plt.has_plt0 = 1;
2223 normal_target = plt_layout->normal_target;
2224
2225 if (normal_target)
2226 {
2227 if (use_ibt_plt)
2228 {
2229 htab->lazy_plt = plt_layout->lazy_ibt_plt;
2230 htab->non_lazy_plt = plt_layout->non_lazy_ibt_plt;
2231 }
2232 else
2233 {
2234 htab->lazy_plt = plt_layout->lazy_plt;
2235 htab->non_lazy_plt = plt_layout->non_lazy_plt;
2236 }
2237 }
2238 else
2239 {
2240 htab->lazy_plt = plt_layout->lazy_plt;
2241 htab->non_lazy_plt = NULL;
2242 }
2243
2244 pltsec = htab->elf.splt;
2245
2246 /* If the non-lazy PLT is available, use it for all PLT entries if
2247 there are no PLT0 or no .plt section. */
2248 if (htab->non_lazy_plt != NULL
2249 && (!htab->plt.has_plt0 || pltsec == NULL))
2250 {
2251 lazy_plt = FALSE;
2252 if (bfd_link_pic (info))
2253 htab->plt.plt_entry = htab->non_lazy_plt->pic_plt_entry;
2254 else
2255 htab->plt.plt_entry = htab->non_lazy_plt->plt_entry;
2256 htab->plt.plt_entry_size = htab->non_lazy_plt->plt_entry_size;
2257 htab->plt.plt_got_offset = htab->non_lazy_plt->plt_got_offset;
2258 htab->plt.plt_got_insn_size
2259 = htab->non_lazy_plt->plt_got_insn_size;
2260 htab->plt.eh_frame_plt_size
2261 = htab->non_lazy_plt->eh_frame_plt_size;
2262 htab->plt.eh_frame_plt = htab->non_lazy_plt->eh_frame_plt;
2263 }
2264 else
2265 {
2266 lazy_plt = TRUE;
2267 if (bfd_link_pic (info))
2268 {
2269 htab->plt.plt0_entry = htab->lazy_plt->pic_plt0_entry;
2270 htab->plt.plt_entry = htab->lazy_plt->pic_plt_entry;
2271 }
2272 else
2273 {
2274 htab->plt.plt0_entry = htab->lazy_plt->plt0_entry;
2275 htab->plt.plt_entry = htab->lazy_plt->plt_entry;
2276 }
2277 htab->plt.plt_entry_size = htab->lazy_plt->plt_entry_size;
2278 htab->plt.plt_got_offset = htab->lazy_plt->plt_got_offset;
2279 htab->plt.plt_got_insn_size
2280 = htab->lazy_plt->plt_got_insn_size;
2281 htab->plt.eh_frame_plt_size
2282 = htab->lazy_plt->eh_frame_plt_size;
2283 htab->plt.eh_frame_plt = htab->lazy_plt->eh_frame_plt;
2284 }
2285
2286 /* Return if there are no normal input files. */
2287 if (dynobj == NULL)
2288 return pbfd;
2289
2290 if (htab->is_vxworks
2291 && !elf_vxworks_create_dynamic_sections (dynobj, info,
2292 &htab->srelplt2))
2293 {
2294 info->callbacks->einfo (_("%F: failed to create VxWorks dynamic sections\n"));
2295 return pbfd;
2296 }
2297
2298 /* Since create_dynamic_sections isn't always called, but GOT
2299 relocations need GOT relocations, create them here so that we
2300 don't need to do it in check_relocs. */
2301 if (htab->elf.sgot == NULL
2302 && !_bfd_elf_create_got_section (dynobj, info))
2303 info->callbacks->einfo (_("%F: failed to create GOT sections\n"));
2304
2305 got_align = (bed->target_id == X86_64_ELF_DATA) ? 3 : 2;
2306
2307 /* Align .got and .got.plt sections to their entry size. Do it here
2308 instead of in create_dynamic_sections so that they are always
2309 properly aligned even if create_dynamic_sections isn't called. */
2310 sec = htab->elf.sgot;
2311 if (!bfd_set_section_alignment (dynobj, sec, got_align))
2312 goto error_alignment;
2313
2314 sec = htab->elf.sgotplt;
2315 if (!bfd_set_section_alignment (dynobj, sec, got_align))
2316 goto error_alignment;
2317
2318 /* Create the ifunc sections here so that check_relocs can be
2319 simplified. */
2320 if (!_bfd_elf_create_ifunc_sections (dynobj, info))
2321 info->callbacks->einfo (_("%F: failed to create ifunc sections\n"));
2322
2323 plt_alignment = bfd_log2 (htab->plt.plt_entry_size);
2324
2325 if (pltsec != NULL)
2326 {
2327 /* Whe creating executable, set the contents of the .interp
2328 section to the interpreter. */
2329 if (bfd_link_executable (info) && !info->nointerp)
2330 {
2331 asection *s = bfd_get_linker_section (dynobj, ".interp");
2332 if (s == NULL)
2333 abort ();
2334 s->size = htab->dynamic_interpreter_size;
2335 s->contents = (unsigned char *) htab->dynamic_interpreter;
2336 htab->interp = s;
2337 }
2338
2339 /* Don't change PLT section alignment for NaCl since it uses
2340 64-byte PLT entry and sets PLT section alignment to 32
2341 bytes. Don't create additional PLT sections for NaCl. */
2342 if (normal_target)
2343 {
2344 flagword pltflags = (bed->dynamic_sec_flags
2345 | SEC_ALLOC
2346 | SEC_CODE
2347 | SEC_LOAD
2348 | SEC_READONLY);
2349 unsigned int non_lazy_plt_alignment
2350 = bfd_log2 (htab->non_lazy_plt->plt_entry_size);
2351
2352 sec = pltsec;
2353 if (!bfd_set_section_alignment (sec->owner, sec,
2354 plt_alignment))
2355 goto error_alignment;
2356
2357 /* Create the GOT procedure linkage table. */
2358 sec = bfd_make_section_anyway_with_flags (dynobj,
2359 ".plt.got",
2360 pltflags);
2361 if (sec == NULL)
2362 info->callbacks->einfo (_("%F: failed to create GOT PLT section\n"));
2363
2364 if (!bfd_set_section_alignment (dynobj, sec,
2365 non_lazy_plt_alignment))
2366 goto error_alignment;
2367
2368 htab->plt_got = sec;
2369
2370 if (lazy_plt)
2371 {
2372 sec = NULL;
2373
2374 if (use_ibt_plt)
2375 {
2376 /* Create the second PLT for Intel IBT support. IBT
2377 PLT is supported only for non-NaCl target and is
2378 is needed only for lazy binding. */
2379 sec = bfd_make_section_anyway_with_flags (dynobj,
2380 ".plt.sec",
2381 pltflags);
2382 if (sec == NULL)
2383 info->callbacks->einfo (_("%F: failed to create IBT-enabled PLT section\n"));
2384
2385 if (!bfd_set_section_alignment (dynobj, sec,
2386 plt_alignment))
2387 goto error_alignment;
2388 }
2389 else if (info->bndplt && ABI_64_P (dynobj))
2390 {
2391 /* Create the second PLT for Intel MPX support. MPX
2392 PLT is supported only for non-NaCl target in 64-bit
2393 mode and is needed only for lazy binding. */
2394 sec = bfd_make_section_anyway_with_flags (dynobj,
2395 ".plt.sec",
2396 pltflags);
2397 if (sec == NULL)
2398 info->callbacks->einfo (_("%F: failed to create BND PLT section\n"));
2399
2400 if (!bfd_set_section_alignment (dynobj, sec,
2401 non_lazy_plt_alignment))
2402 goto error_alignment;
2403 }
2404
2405 htab->plt_second = sec;
2406 }
2407 }
2408
2409 if (!info->no_ld_generated_unwind_info)
2410 {
2411 flagword flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY
2412 | SEC_HAS_CONTENTS | SEC_IN_MEMORY
2413 | SEC_LINKER_CREATED);
2414
2415 sec = bfd_make_section_anyway_with_flags (dynobj,
2416 ".eh_frame",
2417 flags);
2418 if (sec == NULL)
2419 info->callbacks->einfo (_("%F: failed to create PLT .eh_frame section\n"));
2420
2421 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2422 goto error_alignment;
2423
2424 htab->plt_eh_frame = sec;
2425
2426 if (htab->plt_got != NULL)
2427 {
2428 sec = bfd_make_section_anyway_with_flags (dynobj,
2429 ".eh_frame",
2430 flags);
2431 if (sec == NULL)
2432 info->callbacks->einfo (_("%F: failed to create GOT PLT .eh_frame section\n"));
2433
2434 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2435 goto error_alignment;
2436
2437 htab->plt_got_eh_frame = sec;
2438 }
2439
2440 if (htab->plt_second != NULL)
2441 {
2442 sec = bfd_make_section_anyway_with_flags (dynobj,
2443 ".eh_frame",
2444 flags);
2445 if (sec == NULL)
2446 info->callbacks->einfo (_("%F: failed to create the second PLT .eh_frame section\n"));
2447
2448 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2449 goto error_alignment;
2450
2451 htab->plt_second_eh_frame = sec;
2452 }
2453 }
2454 }
2455
2456 if (normal_target)
2457 {
2458 /* The .iplt section is used for IFUNC symbols in static
2459 executables. */
2460 sec = htab->elf.iplt;
2461 if (sec != NULL
2462 && !bfd_set_section_alignment (sec->owner, sec,
2463 plt_alignment))
2464 goto error_alignment;
2465 }
2466
2467 return pbfd;
2468 }
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