Update ChangeLog entry for PR 22163
[deliverable/binutils-gdb.git] / bfd / elfxx-x86.c
CommitLineData
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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"
a6798bab 22#include "elf-vxworks.h"
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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"
0afcef53 33
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34bfd_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
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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
47void
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
73bfd_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
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82/* Allocate space in .plt, .got and associated reloc sections for
83 dynamic relocs. */
84
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85static bfd_boolean
86elf_x86_allocate_dynrelocs (struct elf_link_hash_entry *h,
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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
c5bce5c6 110 resolved_to_zero = UNDEFINED_WEAK_RESOLVED_TO_ZERO (info, eh);
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111
112 /* Clear the reference count of function pointer relocations if
113 symbol isn't a normal function. */
114 if (h->type != STT_FUNC)
115 eh->func_pointer_refcount = 0;
116
117 /* We can't use the GOT PLT if pointer equality is needed since
118 finish_dynamic_symbol won't clear symbol value and the dynamic
119 linker won't update the GOT slot. We will get into an infinite
120 loop at run-time. */
121 if (htab->plt_got != NULL
122 && h->type != STT_GNU_IFUNC
123 && !h->pointer_equality_needed
124 && h->plt.refcount > 0
125 && h->got.refcount > 0)
126 {
127 /* Don't use the regular PLT if there are both GOT and GOTPLT
128 reloctions. */
129 h->plt.offset = (bfd_vma) -1;
130
131 /* Use the GOT PLT. */
132 eh->plt_got.refcount = 1;
133 }
134
135 /* Since STT_GNU_IFUNC symbol must go through PLT, we handle it
136 here if it is defined and referenced in a non-shared object. */
137 if (h->type == STT_GNU_IFUNC
138 && h->def_regular)
139 {
140 if (_bfd_elf_allocate_ifunc_dyn_relocs (info, h, &eh->dyn_relocs,
141 &htab->readonly_dynrelocs_against_ifunc,
142 plt_entry_size,
143 (htab->plt.has_plt0
144 * plt_entry_size),
145 htab->got_entry_size,
146 TRUE))
147 {
148 asection *s = htab->plt_second;
149 if (h->plt.offset != (bfd_vma) -1 && s != NULL)
150 {
151 /* Use the second PLT section if it is created. */
152 eh->plt_second.offset = s->size;
153
154 /* Make room for this entry in the second PLT section. */
155 s->size += htab->non_lazy_plt->plt_entry_size;
156 }
157
158 return TRUE;
159 }
160 else
161 return FALSE;
162 }
163 /* Don't create the PLT entry if there are only function pointer
164 relocations which can be resolved at run-time. */
165 else if (htab->elf.dynamic_sections_created
166 && (h->plt.refcount > eh->func_pointer_refcount
167 || eh->plt_got.refcount > 0))
168 {
169 bfd_boolean use_plt_got = eh->plt_got.refcount > 0;
170
171 /* Clear the reference count of function pointer relocations
172 if PLT is used. */
173 eh->func_pointer_refcount = 0;
174
175 /* Make sure this symbol is output as a dynamic symbol.
176 Undefined weak syms won't yet be marked as dynamic. */
177 if (h->dynindx == -1
178 && !h->forced_local
179 && !resolved_to_zero
180 && h->root.type == bfd_link_hash_undefweak)
181 {
182 if (! bfd_elf_link_record_dynamic_symbol (info, h))
183 return FALSE;
184 }
185
186 if (bfd_link_pic (info)
187 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h))
188 {
189 asection *s = htab->elf.splt;
190 asection *second_s = htab->plt_second;
191 asection *got_s = htab->plt_got;
192
193 /* If this is the first .plt entry, make room for the special
194 first entry. The .plt section is used by prelink to undo
195 prelinking for dynamic relocations. */
196 if (s->size == 0)
197 s->size = htab->plt.has_plt0 * plt_entry_size;
198
199 if (use_plt_got)
200 eh->plt_got.offset = got_s->size;
201 else
202 {
203 h->plt.offset = s->size;
204 if (second_s)
205 eh->plt_second.offset = second_s->size;
206 }
207
208 /* If this symbol is not defined in a regular file, and we are
209 not generating a shared library, then set the symbol to this
210 location in the .plt. This is required to make function
211 pointers compare as equal between the normal executable and
212 the shared library. */
213 if (! bfd_link_pic (info)
214 && !h->def_regular)
215 {
216 if (use_plt_got)
217 {
218 /* We need to make a call to the entry of the GOT PLT
219 instead of regular PLT entry. */
220 h->root.u.def.section = got_s;
221 h->root.u.def.value = eh->plt_got.offset;
222 }
223 else
224 {
225 if (second_s)
226 {
227 /* We need to make a call to the entry of the
228 second PLT instead of regular PLT entry. */
229 h->root.u.def.section = second_s;
230 h->root.u.def.value = eh->plt_second.offset;
231 }
232 else
233 {
234 h->root.u.def.section = s;
235 h->root.u.def.value = h->plt.offset;
236 }
237 }
238 }
239
240 /* Make room for this entry. */
241 if (use_plt_got)
242 got_s->size += htab->non_lazy_plt->plt_entry_size;
243 else
244 {
245 s->size += plt_entry_size;
246 if (second_s)
247 second_s->size += htab->non_lazy_plt->plt_entry_size;
248
249 /* We also need to make an entry in the .got.plt section,
250 which will be placed in the .got section by the linker
251 script. */
252 htab->elf.sgotplt->size += htab->got_entry_size;
253
254 /* There should be no PLT relocation against resolved
255 undefined weak symbol in executable. */
256 if (!resolved_to_zero)
257 {
258 /* We also need to make an entry in the .rel.plt
259 section. */
260 htab->elf.srelplt->size += htab->sizeof_reloc;
261 htab->elf.srelplt->reloc_count++;
262 }
263 }
264
265 if (htab->is_vxworks && !bfd_link_pic (info))
266 {
267 /* VxWorks has a second set of relocations for each PLT entry
268 in executables. They go in a separate relocation section,
269 which is processed by the kernel loader. */
270
271 /* There are two relocations for the initial PLT entry: an
272 R_386_32 relocation for _GLOBAL_OFFSET_TABLE_ + 4 and an
273 R_386_32 relocation for _GLOBAL_OFFSET_TABLE_ + 8. */
274
275 asection *srelplt2 = htab->srelplt2;
276 if (h->plt.offset == plt_entry_size)
277 srelplt2->size += (htab->sizeof_reloc * 2);
278
279 /* There are two extra relocations for each subsequent PLT entry:
280 an R_386_32 relocation for the GOT entry, and an R_386_32
281 relocation for the PLT entry. */
282
283 srelplt2->size += (htab->sizeof_reloc * 2);
284 }
285 }
286 else
287 {
288 eh->plt_got.offset = (bfd_vma) -1;
289 h->plt.offset = (bfd_vma) -1;
290 h->needs_plt = 0;
291 }
292 }
293 else
294 {
295 eh->plt_got.offset = (bfd_vma) -1;
296 h->plt.offset = (bfd_vma) -1;
297 h->needs_plt = 0;
298 }
299
300 eh->tlsdesc_got = (bfd_vma) -1;
301
302 /* For i386, if R_386_TLS_{IE_32,IE,GOTIE} symbol is now local to the
303 binary, make it a R_386_TLS_LE_32 requiring no TLS entry. For
304 x86-64, if R_X86_64_GOTTPOFF symbol is now local to the binary,
305 make it a R_X86_64_TPOFF32 requiring no GOT entry. */
306 if (h->got.refcount > 0
307 && bfd_link_executable (info)
308 && h->dynindx == -1
309 && (elf_x86_hash_entry (h)->tls_type & GOT_TLS_IE))
310 h->got.offset = (bfd_vma) -1;
311 else if (h->got.refcount > 0)
312 {
313 asection *s;
314 bfd_boolean dyn;
315 int tls_type = elf_x86_hash_entry (h)->tls_type;
316
317 /* Make sure this symbol is output as a dynamic symbol.
318 Undefined weak syms won't yet be marked as dynamic. */
319 if (h->dynindx == -1
320 && !h->forced_local
321 && !resolved_to_zero
322 && h->root.type == bfd_link_hash_undefweak)
323 {
324 if (! bfd_elf_link_record_dynamic_symbol (info, h))
325 return FALSE;
326 }
327
328 s = htab->elf.sgot;
329 if (GOT_TLS_GDESC_P (tls_type))
330 {
331 eh->tlsdesc_got = htab->elf.sgotplt->size
332 - elf_x86_compute_jump_table_size (htab);
333 htab->elf.sgotplt->size += 2 * htab->got_entry_size;
334 h->got.offset = (bfd_vma) -2;
335 }
336 if (! GOT_TLS_GDESC_P (tls_type)
337 || GOT_TLS_GD_P (tls_type))
338 {
339 h->got.offset = s->size;
340 s->size += htab->got_entry_size;
341 /* R_386_TLS_GD and R_X86_64_TLSGD need 2 consecutive GOT
342 slots. */
343 if (GOT_TLS_GD_P (tls_type) || tls_type == GOT_TLS_IE_BOTH)
344 s->size += htab->got_entry_size;
345 }
346 dyn = htab->elf.dynamic_sections_created;
347 /* R_386_TLS_IE_32 needs one dynamic relocation,
348 R_386_TLS_IE resp. R_386_TLS_GOTIE needs one dynamic relocation,
349 (but if both R_386_TLS_IE_32 and R_386_TLS_IE is present, we
350 need two), R_386_TLS_GD and R_X86_64_TLSGD need one if local
351 symbol and two if global. No dynamic relocation against
352 resolved undefined weak symbol in executable. */
353 if (tls_type == GOT_TLS_IE_BOTH)
354 htab->elf.srelgot->size += 2 * htab->sizeof_reloc;
355 else if ((GOT_TLS_GD_P (tls_type) && h->dynindx == -1)
356 || (tls_type & GOT_TLS_IE))
357 htab->elf.srelgot->size += htab->sizeof_reloc;
358 else if (GOT_TLS_GD_P (tls_type))
359 htab->elf.srelgot->size += 2 * htab->sizeof_reloc;
360 else if (! GOT_TLS_GDESC_P (tls_type)
361 && ((ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
362 && !resolved_to_zero)
363 || h->root.type != bfd_link_hash_undefweak)
364 && (bfd_link_pic (info)
365 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h)))
366 htab->elf.srelgot->size += htab->sizeof_reloc;
367 if (GOT_TLS_GDESC_P (tls_type))
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368 {
369 htab->elf.srelplt->size += htab->sizeof_reloc;
370 if (bed->target_id == X86_64_ELF_DATA)
371 htab->tlsdesc_plt = (bfd_vma) -1;
372 }
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373 }
374 else
375 h->got.offset = (bfd_vma) -1;
376
377 if (eh->dyn_relocs == NULL)
378 return TRUE;
379
380 /* In the shared -Bsymbolic case, discard space allocated for
381 dynamic pc-relative relocs against symbols which turn out to be
382 defined in regular objects. For the normal shared case, discard
383 space for pc-relative relocs that have become local due to symbol
384 visibility changes. */
385
386 if (bfd_link_pic (info))
387 {
388 /* Relocs that use pc_count are those that appear on a call
389 insn, or certain REL relocs that can generated via assembly.
390 We want calls to protected symbols to resolve directly to the
391 function rather than going via the plt. If people want
392 function pointer comparisons to work as expected then they
393 should avoid writing weird assembly. */
394 if (SYMBOL_CALLS_LOCAL (info, h))
395 {
396 struct elf_dyn_relocs **pp;
397
398 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
399 {
400 p->count -= p->pc_count;
401 p->pc_count = 0;
402 if (p->count == 0)
403 *pp = p->next;
404 else
405 pp = &p->next;
406 }
407 }
408
409 if (htab->is_vxworks)
410 {
411 struct elf_dyn_relocs **pp;
412 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
413 {
414 if (strcmp (p->sec->output_section->name, ".tls_vars") == 0)
415 *pp = p->next;
416 else
417 pp = &p->next;
418 }
419 }
420
421 /* Also discard relocs on undefined weak syms with non-default
422 visibility or in PIE. */
423 if (eh->dyn_relocs != NULL)
424 {
425 if (h->root.type == bfd_link_hash_undefweak)
426 {
427 /* Undefined weak symbol is never bound locally in shared
428 library. */
429 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
430 || resolved_to_zero)
431 {
432 if (bed->target_id == I386_ELF_DATA
433 && h->non_got_ref)
434 {
435 /* Keep dynamic non-GOT/non-PLT relocation so
436 that we can branch to 0 without PLT. */
437 struct elf_dyn_relocs **pp;
438
439 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
440 if (p->pc_count == 0)
441 *pp = p->next;
442 else
443 {
444 /* Remove non-R_386_PC32 relocation. */
445 p->count = p->pc_count;
446 pp = &p->next;
447 }
448
449 /* Make sure undefined weak symbols are output
450 as dynamic symbols in PIEs for dynamic non-GOT
451 non-PLT reloations. */
452 if (eh->dyn_relocs != NULL
453 && !bfd_elf_link_record_dynamic_symbol (info, h))
454 return FALSE;
455 }
456 else
457 eh->dyn_relocs = NULL;
458 }
459 else if (h->dynindx == -1
460 && !h->forced_local
461 && !bfd_elf_link_record_dynamic_symbol (info, h))
462 return FALSE;
463 }
464 else if (bfd_link_executable (info)
465 && (h->needs_copy || eh->needs_copy)
466 && h->def_dynamic
467 && !h->def_regular)
468 {
469 /* NB: needs_copy is set only for x86-64. For PIE,
470 discard space for pc-relative relocs against symbols
471 which turn out to need copy relocs. */
472 struct elf_dyn_relocs **pp;
473
474 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
475 {
476 if (p->pc_count != 0)
477 *pp = p->next;
478 else
479 pp = &p->next;
480 }
481 }
482 }
483 }
484 else if (ELIMINATE_COPY_RELOCS)
485 {
486 /* For the non-shared case, discard space for relocs against
487 symbols which turn out to need copy relocs or are not
488 dynamic. Keep dynamic relocations for run-time function
489 pointer initialization. */
490
491 if ((!h->non_got_ref
492 || eh->func_pointer_refcount > 0
493 || (h->root.type == bfd_link_hash_undefweak
494 && !resolved_to_zero))
495 && ((h->def_dynamic
496 && !h->def_regular)
497 || (htab->elf.dynamic_sections_created
498 && (h->root.type == bfd_link_hash_undefweak
499 || h->root.type == bfd_link_hash_undefined))))
500 {
501 /* Make sure this symbol is output as a dynamic symbol.
502 Undefined weak syms won't yet be marked as dynamic. */
503 if (h->dynindx == -1
504 && !h->forced_local
505 && !resolved_to_zero
506 && h->root.type == bfd_link_hash_undefweak
507 && ! bfd_elf_link_record_dynamic_symbol (info, h))
508 return FALSE;
509
510 /* If that succeeded, we know we'll be keeping all the
511 relocs. */
512 if (h->dynindx != -1)
513 goto keep;
514 }
515
516 eh->dyn_relocs = NULL;
517 eh->func_pointer_refcount = 0;
518
519 keep: ;
520 }
521
522 /* Finally, allocate space. */
523 for (p = eh->dyn_relocs; p != NULL; p = p->next)
524 {
525 asection *sreloc;
526
527 sreloc = elf_section_data (p->sec)->sreloc;
528
529 BFD_ASSERT (sreloc != NULL);
530 sreloc->size += p->count * htab->sizeof_reloc;
531 }
532
533 return TRUE;
534}
535
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536/* Find any dynamic relocs that apply to read-only sections. */
537
538bfd_boolean
539_bfd_x86_elf_readonly_dynrelocs (struct elf_link_hash_entry *h,
540 void *inf)
541{
542 struct elf_x86_link_hash_entry *eh;
543 struct elf_dyn_relocs *p;
544
545 /* Skip local IFUNC symbols. */
546 if (h->forced_local && h->type == STT_GNU_IFUNC)
547 return TRUE;
548
549 eh = (struct elf_x86_link_hash_entry *) h;
550 for (p = eh->dyn_relocs; p != NULL; p = p->next)
551 {
552 asection *s = p->sec->output_section;
553
554 if (s != NULL && (s->flags & SEC_READONLY) != 0)
555 {
556 struct bfd_link_info *info = (struct bfd_link_info *) inf;
557
558 info->flags |= DF_TEXTREL;
559
560 if ((info->warn_shared_textrel && bfd_link_pic (info))
561 || info->error_textrel)
562 /* xgettext:c-format */
563 info->callbacks->einfo (_("%P: %B: warning: relocation against `%s' in readonly section `%A'\n"),
564 p->sec->owner, h->root.root.string,
565 p->sec);
566
567 /* Not an error, just cut short the traversal. */
568 return FALSE;
569 }
570 }
571 return TRUE;
572}
573
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574/* Allocate space in .plt, .got and associated reloc sections for
575 local dynamic relocs. */
576
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577static bfd_boolean
578elf_x86_allocate_local_dynreloc (void **slot, void *inf)
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579{
580 struct elf_link_hash_entry *h
581 = (struct elf_link_hash_entry *) *slot;
582
583 if (h->type != STT_GNU_IFUNC
584 || !h->def_regular
585 || !h->ref_regular
586 || !h->forced_local
587 || h->root.type != bfd_link_hash_defined)
588 abort ();
589
5e2ac45d 590 return elf_x86_allocate_dynrelocs (h, inf);
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591}
592
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593/* Find and/or create a hash entry for local symbol. */
594
595struct elf_link_hash_entry *
596_bfd_elf_x86_get_local_sym_hash (struct elf_x86_link_hash_table *htab,
597 bfd *abfd, const Elf_Internal_Rela *rel,
598 bfd_boolean create)
599{
600 struct elf_x86_link_hash_entry e, *ret;
601 asection *sec = abfd->sections;
602 hashval_t h = ELF_LOCAL_SYMBOL_HASH (sec->id,
603 htab->r_sym (rel->r_info));
604 void **slot;
605
606 e.elf.indx = sec->id;
607 e.elf.dynstr_index = htab->r_sym (rel->r_info);
608 slot = htab_find_slot_with_hash (htab->loc_hash_table, &e, h,
609 create ? INSERT : NO_INSERT);
610
611 if (!slot)
612 return NULL;
613
614 if (*slot)
615 {
616 ret = (struct elf_x86_link_hash_entry *) *slot;
617 return &ret->elf;
618 }
619
620 ret = (struct elf_x86_link_hash_entry *)
621 objalloc_alloc ((struct objalloc *) htab->loc_hash_memory,
622 sizeof (struct elf_x86_link_hash_entry));
623 if (ret)
624 {
625 memset (ret, 0, sizeof (*ret));
626 ret->elf.indx = sec->id;
627 ret->elf.dynstr_index = htab->r_sym (rel->r_info);
628 ret->elf.dynindx = -1;
629 ret->plt_got.offset = (bfd_vma) -1;
630 *slot = ret;
631 }
632 return &ret->elf;
633}
634
635/* Create an entry in a x86 ELF linker hash table. NB: THIS MUST BE IN
636 SYNC WITH _bfd_elf_link_hash_newfunc. */
637
638struct bfd_hash_entry *
639_bfd_x86_elf_link_hash_newfunc (struct bfd_hash_entry *entry,
640 struct bfd_hash_table *table,
641 const char *string)
642{
643 /* Allocate the structure if it has not already been allocated by a
644 subclass. */
645 if (entry == NULL)
646 {
647 entry = (struct bfd_hash_entry *)
648 bfd_hash_allocate (table,
649 sizeof (struct elf_x86_link_hash_entry));
650 if (entry == NULL)
651 return entry;
652 }
653
654 /* Call the allocation method of the superclass. */
655 entry = _bfd_link_hash_newfunc (entry, table, string);
656 if (entry != NULL)
657 {
658 struct elf_x86_link_hash_entry *eh
659 = (struct elf_x86_link_hash_entry *) entry;
660 struct elf_link_hash_table *htab
661 = (struct elf_link_hash_table *) table;
662
663 memset (&eh->elf.size, 0,
664 (sizeof (struct elf_x86_link_hash_entry)
665 - offsetof (struct elf_link_hash_entry, size)));
666 /* Set local fields. */
667 eh->elf.indx = -1;
668 eh->elf.dynindx = -1;
669 eh->elf.got = htab->init_got_refcount;
670 eh->elf.plt = htab->init_plt_refcount;
671 /* Assume that we have been called by a non-ELF symbol reader.
672 This flag is then reset by the code which reads an ELF input
673 file. This ensures that a symbol created by a non-ELF symbol
674 reader will have the flag set correctly. */
675 eh->elf.non_elf = 1;
676 eh->plt_second.offset = (bfd_vma) -1;
677 eh->plt_got.offset = (bfd_vma) -1;
678 eh->tlsdesc_got = (bfd_vma) -1;
679 }
680
681 return entry;
682}
683
684/* Compute a hash of a local hash entry. We use elf_link_hash_entry
685 for local symbol so that we can handle local STT_GNU_IFUNC symbols
686 as global symbol. We reuse indx and dynstr_index for local symbol
687 hash since they aren't used by global symbols in this backend. */
688
689hashval_t
690_bfd_x86_elf_local_htab_hash (const void *ptr)
691{
692 struct elf_link_hash_entry *h
693 = (struct elf_link_hash_entry *) ptr;
694 return ELF_LOCAL_SYMBOL_HASH (h->indx, h->dynstr_index);
695}
696
697/* Compare local hash entries. */
698
699int
700_bfd_x86_elf_local_htab_eq (const void *ptr1, const void *ptr2)
701{
702 struct elf_link_hash_entry *h1
703 = (struct elf_link_hash_entry *) ptr1;
704 struct elf_link_hash_entry *h2
705 = (struct elf_link_hash_entry *) ptr2;
706
707 return h1->indx == h2->indx && h1->dynstr_index == h2->dynstr_index;
708}
709
710/* Destroy an x86 ELF linker hash table. */
711
765e526c
L
712static void
713elf_x86_link_hash_table_free (bfd *obfd)
0afcef53
L
714{
715 struct elf_x86_link_hash_table *htab
716 = (struct elf_x86_link_hash_table *) obfd->link.hash;
717
718 if (htab->loc_hash_table)
719 htab_delete (htab->loc_hash_table);
720 if (htab->loc_hash_memory)
721 objalloc_free ((struct objalloc *) htab->loc_hash_memory);
722 _bfd_elf_link_hash_table_free (obfd);
723}
724
5e2ac45d
L
725static bfd_boolean
726elf_i386_is_reloc_section (const char *secname)
727{
728 return CONST_STRNEQ (secname, ".rel");
729}
730
5e2ac45d
L
731static bfd_boolean
732elf_x86_64_is_reloc_section (const char *secname)
733{
734 return CONST_STRNEQ (secname, ".rela");
735}
5e2ac45d 736
765e526c
L
737/* Create an x86 ELF linker hash table. */
738
739struct bfd_link_hash_table *
740_bfd_x86_elf_link_hash_table_create (bfd *abfd)
741{
742 struct elf_x86_link_hash_table *ret;
743 const struct elf_backend_data *bed;
744 bfd_size_type amt = sizeof (struct elf_x86_link_hash_table);
745
746 ret = (struct elf_x86_link_hash_table *) bfd_zmalloc (amt);
747 if (ret == NULL)
748 return NULL;
749
750 bed = get_elf_backend_data (abfd);
751 if (!_bfd_elf_link_hash_table_init (&ret->elf, abfd,
752 _bfd_x86_elf_link_hash_newfunc,
753 sizeof (struct elf_x86_link_hash_entry),
754 bed->target_id))
755 {
756 free (ret);
757 return NULL;
758 }
759
5e2ac45d
L
760 if (bed->target_id == X86_64_ELF_DATA)
761 {
5e2ac45d
L
762 ret->is_reloc_section = elf_x86_64_is_reloc_section;
763 ret->dt_reloc = DT_RELA;
764 ret->dt_reloc_sz = DT_RELASZ;
765 ret->dt_reloc_ent = DT_RELAENT;
766 ret->got_entry_size = 8;
f04bdfa7 767 ret->tls_get_addr = "__tls_get_addr";
5e2ac45d 768 }
765e526c
L
769 if (ABI_64_P (abfd))
770 {
503294e7 771 ret->sizeof_reloc = sizeof (Elf64_External_Rela);
765e526c
L
772 ret->pointer_r_type = R_X86_64_64;
773 ret->dynamic_interpreter = ELF64_DYNAMIC_INTERPRETER;
774 ret->dynamic_interpreter_size = sizeof ELF64_DYNAMIC_INTERPRETER;
765e526c
L
775 }
776 else
765e526c 777 {
5b86dbf4 778 if (bed->target_id == X86_64_ELF_DATA)
765e526c 779 {
503294e7 780 ret->sizeof_reloc = sizeof (Elf32_External_Rela);
765e526c
L
781 ret->pointer_r_type = R_X86_64_32;
782 ret->dynamic_interpreter = ELFX32_DYNAMIC_INTERPRETER;
783 ret->dynamic_interpreter_size
784 = sizeof ELFX32_DYNAMIC_INTERPRETER;
765e526c
L
785 }
786 else
787 {
5e2ac45d
L
788 ret->is_reloc_section = elf_i386_is_reloc_section;
789 ret->dt_reloc = DT_REL;
790 ret->dt_reloc_sz = DT_RELSZ;
791 ret->dt_reloc_ent = DT_RELENT;
503294e7 792 ret->sizeof_reloc = sizeof (Elf32_External_Rel);
9ff114ca 793 ret->got_entry_size = 4;
765e526c
L
794 ret->pointer_r_type = R_386_32;
795 ret->dynamic_interpreter = ELF32_DYNAMIC_INTERPRETER;
796 ret->dynamic_interpreter_size
797 = sizeof ELF32_DYNAMIC_INTERPRETER;
798 ret->tls_get_addr = "___tls_get_addr";
799 }
800 }
fe53b4a4 801 ret->target_id = bed->target_id;
765e526c
L
802
803 ret->loc_hash_table = htab_try_create (1024,
804 _bfd_x86_elf_local_htab_hash,
805 _bfd_x86_elf_local_htab_eq,
806 NULL);
807 ret->loc_hash_memory = objalloc_create ();
808 if (!ret->loc_hash_table || !ret->loc_hash_memory)
809 {
810 elf_x86_link_hash_table_free (abfd);
811 return NULL;
812 }
813 ret->elf.root.hash_table_free = elf_x86_link_hash_table_free;
814
815 return &ret->elf.root;
816}
817
0afcef53
L
818/* Sort relocs into address order. */
819
820int
821_bfd_x86_elf_compare_relocs (const void *ap, const void *bp)
822{
823 const arelent *a = * (const arelent **) ap;
824 const arelent *b = * (const arelent **) bp;
825
826 if (a->address > b->address)
827 return 1;
828 else if (a->address < b->address)
829 return -1;
830 else
831 return 0;
832}
833
834bfd_boolean
835_bfd_x86_elf_link_check_relocs (bfd *abfd, struct bfd_link_info *info)
836{
837 if (!bfd_link_relocatable (info))
838 {
839 /* Check for __tls_get_addr reference. */
840 struct elf_x86_link_hash_table *htab;
841 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
842 htab = elf_x86_hash_table (info, bed->target_id);
843 if (htab)
844 {
0a27fed7
L
845 struct elf_link_hash_entry *h;
846
847 h = elf_link_hash_lookup (elf_hash_table (info),
0afcef53
L
848 htab->tls_get_addr,
849 FALSE, FALSE, FALSE);
850 if (h != NULL)
0a27fed7
L
851 elf_x86_hash_entry (h)->tls_get_addr = 1;
852
853 /* "__ehdr_start" will be defined by linker as a hidden symbol
854 later if it is referenced and not defined. */
855 h = elf_link_hash_lookup (elf_hash_table (info),
856 "__ehdr_start",
857 FALSE, FALSE, FALSE);
858 if (h != NULL
859 && (h->root.type == bfd_link_hash_new
860 || h->root.type == bfd_link_hash_undefined
861 || h->root.type == bfd_link_hash_undefweak
862 || h->root.type == bfd_link_hash_common))
863 {
864 elf_x86_hash_entry (h)->local_ref = 2;
865 elf_x86_hash_entry (h)->linker_def = 1;
866 }
0afcef53
L
867 }
868 }
869
870 /* Invoke the regular ELF backend linker to do all the work. */
871 return _bfd_elf_link_check_relocs (abfd, info);
872}
873
5e2ac45d
L
874/* Set the sizes of the dynamic sections. */
875
876bfd_boolean
877_bfd_x86_elf_size_dynamic_sections (bfd *output_bfd,
878 struct bfd_link_info *info)
879{
880 struct elf_x86_link_hash_table *htab;
881 bfd *dynobj;
882 asection *s;
883 bfd_boolean relocs;
884 bfd *ibfd;
885 const struct elf_backend_data *bed
886 = get_elf_backend_data (output_bfd);
887
888 htab = elf_x86_hash_table (info, bed->target_id);
889 if (htab == NULL)
890 return FALSE;
891 dynobj = htab->elf.dynobj;
892 if (dynobj == NULL)
893 abort ();
894
895 /* Set up .got offsets for local syms, and space for local dynamic
896 relocs. */
897 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
898 {
899 bfd_signed_vma *local_got;
900 bfd_signed_vma *end_local_got;
901 char *local_tls_type;
902 bfd_vma *local_tlsdesc_gotent;
903 bfd_size_type locsymcount;
904 Elf_Internal_Shdr *symtab_hdr;
905 asection *srel;
906
907 if (! is_x86_elf (ibfd, htab))
908 continue;
909
910 for (s = ibfd->sections; s != NULL; s = s->next)
911 {
912 struct elf_dyn_relocs *p;
913
5e2ac45d
L
914 for (p = ((struct elf_dyn_relocs *)
915 elf_section_data (s)->local_dynrel);
916 p != NULL;
917 p = p->next)
918 {
919 if (!bfd_is_abs_section (p->sec)
920 && bfd_is_abs_section (p->sec->output_section))
921 {
922 /* Input section has been discarded, either because
923 it is a copy of a linkonce section or due to
924 linker script /DISCARD/, so we'll be discarding
925 the relocs too. */
926 }
927 else if (htab->is_vxworks
928 && strcmp (p->sec->output_section->name,
929 ".tls_vars") == 0)
930 {
931 /* Relocations in vxworks .tls_vars sections are
932 handled specially by the loader. */
933 }
934 else if (p->count != 0)
935 {
936 srel = elf_section_data (p->sec)->sreloc;
937 srel->size += p->count * htab->sizeof_reloc;
938 if ((p->sec->output_section->flags & SEC_READONLY) != 0
939 && (info->flags & DF_TEXTREL) == 0)
940 {
941 info->flags |= DF_TEXTREL;
942 if ((info->warn_shared_textrel && bfd_link_pic (info))
943 || info->error_textrel)
944 /* xgettext:c-format */
945 info->callbacks->einfo (_("%P: %B: warning: relocation in readonly section `%A'\n"),
946 p->sec->owner, p->sec);
947 }
948 }
949 }
950 }
951
952 local_got = elf_local_got_refcounts (ibfd);
953 if (!local_got)
954 continue;
955
956 symtab_hdr = &elf_symtab_hdr (ibfd);
957 locsymcount = symtab_hdr->sh_info;
958 end_local_got = local_got + locsymcount;
959 local_tls_type = elf_x86_local_got_tls_type (ibfd);
960 local_tlsdesc_gotent = elf_x86_local_tlsdesc_gotent (ibfd);
961 s = htab->elf.sgot;
962 srel = htab->elf.srelgot;
963 for (; local_got < end_local_got;
964 ++local_got, ++local_tls_type, ++local_tlsdesc_gotent)
965 {
966 *local_tlsdesc_gotent = (bfd_vma) -1;
967 if (*local_got > 0)
968 {
969 if (GOT_TLS_GDESC_P (*local_tls_type))
970 {
971 *local_tlsdesc_gotent = htab->elf.sgotplt->size
972 - elf_x86_compute_jump_table_size (htab);
973 htab->elf.sgotplt->size += 2 * htab->got_entry_size;
974 *local_got = (bfd_vma) -2;
975 }
976 if (! GOT_TLS_GDESC_P (*local_tls_type)
977 || GOT_TLS_GD_P (*local_tls_type))
978 {
979 *local_got = s->size;
980 s->size += htab->got_entry_size;
981 if (GOT_TLS_GD_P (*local_tls_type)
982 || *local_tls_type == GOT_TLS_IE_BOTH)
983 s->size += htab->got_entry_size;
984 }
985 if (bfd_link_pic (info)
986 || GOT_TLS_GD_ANY_P (*local_tls_type)
987 || (*local_tls_type & GOT_TLS_IE))
988 {
989 if (*local_tls_type == GOT_TLS_IE_BOTH)
990 srel->size += 2 * htab->sizeof_reloc;
991 else if (GOT_TLS_GD_P (*local_tls_type)
992 || ! GOT_TLS_GDESC_P (*local_tls_type))
993 srel->size += htab->sizeof_reloc;
994 if (GOT_TLS_GDESC_P (*local_tls_type))
995 {
996 htab->elf.srelplt->size += htab->sizeof_reloc;
997 if (bed->target_id == X86_64_ELF_DATA)
998 htab->tlsdesc_plt = (bfd_vma) -1;
999 }
1000 }
1001 }
1002 else
1003 *local_got = (bfd_vma) -1;
1004 }
1005 }
1006
1007 if (htab->tls_ld_or_ldm_got.refcount > 0)
1008 {
1009 /* Allocate 2 got entries and 1 dynamic reloc for R_386_TLS_LDM
1010 or R_X86_64_TLSLD relocs. */
1011 htab->tls_ld_or_ldm_got.offset = htab->elf.sgot->size;
1012 htab->elf.sgot->size += 2 * htab->got_entry_size;
1013 htab->elf.srelgot->size += htab->sizeof_reloc;
1014 }
1015 else
1016 htab->tls_ld_or_ldm_got.offset = -1;
1017
1018 /* Allocate global sym .plt and .got entries, and space for global
1019 sym dynamic relocs. */
1020 elf_link_hash_traverse (&htab->elf, elf_x86_allocate_dynrelocs,
1021 info);
1022
1023 /* Allocate .plt and .got entries, and space for local symbols. */
1024 htab_traverse (htab->loc_hash_table, elf_x86_allocate_local_dynreloc,
1025 info);
1026
1027 /* For every jump slot reserved in the sgotplt, reloc_count is
1028 incremented. However, when we reserve space for TLS descriptors,
1029 it's not incremented, so in order to compute the space reserved
1030 for them, it suffices to multiply the reloc count by the jump
1031 slot size.
1032
1033 PR ld/13302: We start next_irelative_index at the end of .rela.plt
1034 so that R_{386,X86_64}_IRELATIVE entries come last. */
1035 if (htab->elf.srelplt)
1036 {
1037 htab->next_tls_desc_index = htab->elf.srelplt->reloc_count;
1038 htab->sgotplt_jump_table_size
1039 = elf_x86_compute_jump_table_size (htab);
1040 htab->next_irelative_index = htab->elf.srelplt->reloc_count - 1;
1041 }
1042 else if (htab->elf.irelplt)
1043 htab->next_irelative_index = htab->elf.irelplt->reloc_count - 1;
1044
1045 if (htab->tlsdesc_plt)
1046 {
1047 /* NB: tlsdesc_plt is set only for x86-64. If we're not using
1048 lazy TLS relocations, don't generate the PLT and GOT entries
1049 they require. */
1050 if ((info->flags & DF_BIND_NOW))
1051 htab->tlsdesc_plt = 0;
1052 else
1053 {
1054 htab->tlsdesc_got = htab->elf.sgot->size;
1055 htab->elf.sgot->size += htab->got_entry_size;
1056 /* Reserve room for the initial entry.
1057 FIXME: we could probably do away with it in this case. */
1058 if (htab->elf.splt->size == 0)
1059 htab->elf.splt->size = htab->plt.plt_entry_size;
1060 htab->tlsdesc_plt = htab->elf.splt->size;
1061 htab->elf.splt->size += htab->plt.plt_entry_size;
1062 }
1063 }
1064
1065 if (htab->elf.sgotplt)
1066 {
1067 /* Don't allocate .got.plt section if there are no GOT nor PLT
1068 entries and there is no reference to _GLOBAL_OFFSET_TABLE_. */
1069 if ((htab->elf.hgot == NULL
1070 || !htab->elf.hgot->ref_regular_nonweak)
1071 && (htab->elf.sgotplt->size == bed->got_header_size)
1072 && (htab->elf.splt == NULL
1073 || htab->elf.splt->size == 0)
1074 && (htab->elf.sgot == NULL
1075 || htab->elf.sgot->size == 0)
1076 && (htab->elf.iplt == NULL
1077 || htab->elf.iplt->size == 0)
1078 && (htab->elf.igotplt == NULL
1079 || htab->elf.igotplt->size == 0))
1080 htab->elf.sgotplt->size = 0;
1081 }
1082
1083 if (_bfd_elf_eh_frame_present (info))
1084 {
1085 if (htab->plt_eh_frame != NULL
1086 && htab->elf.splt != NULL
1087 && htab->elf.splt->size != 0
1088 && !bfd_is_abs_section (htab->elf.splt->output_section))
1089 htab->plt_eh_frame->size = htab->plt.eh_frame_plt_size;
1090
1091 if (htab->plt_got_eh_frame != NULL
1092 && htab->plt_got != NULL
1093 && htab->plt_got->size != 0
1094 && !bfd_is_abs_section (htab->plt_got->output_section))
1095 htab->plt_got_eh_frame->size
1096 = htab->non_lazy_plt->eh_frame_plt_size;
1097
1098 /* Unwind info for the second PLT and .plt.got sections are
1099 identical. */
1100 if (htab->plt_second_eh_frame != NULL
1101 && htab->plt_second != NULL
1102 && htab->plt_second->size != 0
1103 && !bfd_is_abs_section (htab->plt_second->output_section))
1104 htab->plt_second_eh_frame->size
1105 = htab->non_lazy_plt->eh_frame_plt_size;
1106 }
1107
1108 /* We now have determined the sizes of the various dynamic sections.
1109 Allocate memory for them. */
1110 relocs = FALSE;
1111 for (s = dynobj->sections; s != NULL; s = s->next)
1112 {
1113 bfd_boolean strip_section = TRUE;
1114
1115 if ((s->flags & SEC_LINKER_CREATED) == 0)
1116 continue;
1117
1118 if (s == htab->elf.splt
1119 || s == htab->elf.sgot)
1120 {
1121 /* Strip this section if we don't need it; see the
1122 comment below. */
1123 /* We'd like to strip these sections if they aren't needed, but if
1124 we've exported dynamic symbols from them we must leave them.
1125 It's too late to tell BFD to get rid of the symbols. */
1126
1127 if (htab->elf.hplt != NULL)
1128 strip_section = FALSE;
1129 }
1130 else if (s == htab->elf.sgotplt
1131 || s == htab->elf.iplt
1132 || s == htab->elf.igotplt
1133 || s == htab->plt_second
1134 || s == htab->plt_got
1135 || s == htab->plt_eh_frame
1136 || s == htab->plt_got_eh_frame
1137 || s == htab->plt_second_eh_frame
1138 || s == htab->elf.sdynbss
1139 || s == htab->elf.sdynrelro)
1140 {
1141 /* Strip these too. */
1142 }
1143 else if (htab->is_reloc_section (bfd_get_section_name (dynobj, s)))
1144 {
1145 if (s->size != 0
1146 && s != htab->elf.srelplt
1147 && s != htab->srelplt2)
1148 relocs = TRUE;
1149
1150 /* We use the reloc_count field as a counter if we need
1151 to copy relocs into the output file. */
1152 if (s != htab->elf.srelplt)
1153 s->reloc_count = 0;
1154 }
1155 else
1156 {
1157 /* It's not one of our sections, so don't allocate space. */
1158 continue;
1159 }
1160
1161 if (s->size == 0)
1162 {
1163 /* If we don't need this section, strip it from the
1164 output file. This is mostly to handle .rel.bss and
1165 .rel.plt. We must create both sections in
1166 create_dynamic_sections, because they must be created
1167 before the linker maps input sections to output
1168 sections. The linker does that before
1169 adjust_dynamic_symbol is called, and it is that
1170 function which decides whether anything needs to go
1171 into these sections. */
1172 if (strip_section)
1173 s->flags |= SEC_EXCLUDE;
1174 continue;
1175 }
1176
1177 if ((s->flags & SEC_HAS_CONTENTS) == 0)
1178 continue;
1179
1180 /* Allocate memory for the section contents. We use bfd_zalloc
1181 here in case unused entries are not reclaimed before the
1182 section's contents are written out. This should not happen,
1183 but this way if it does, we get a R_386_NONE or R_X86_64_NONE
1184 reloc instead of garbage. */
1185 s->contents = (unsigned char *) bfd_zalloc (dynobj, s->size);
1186 if (s->contents == NULL)
1187 return FALSE;
1188 }
1189
1190 if (htab->plt_eh_frame != NULL
1191 && htab->plt_eh_frame->contents != NULL)
1192 {
1193 memcpy (htab->plt_eh_frame->contents,
1194 htab->plt.eh_frame_plt,
1195 htab->plt_eh_frame->size);
1196 bfd_put_32 (dynobj, htab->elf.splt->size,
1197 htab->plt_eh_frame->contents + PLT_FDE_LEN_OFFSET);
1198 }
1199
1200 if (htab->plt_got_eh_frame != NULL
1201 && htab->plt_got_eh_frame->contents != NULL)
1202 {
1203 memcpy (htab->plt_got_eh_frame->contents,
1204 htab->non_lazy_plt->eh_frame_plt,
1205 htab->plt_got_eh_frame->size);
1206 bfd_put_32 (dynobj, htab->plt_got->size,
1207 (htab->plt_got_eh_frame->contents
1208 + PLT_FDE_LEN_OFFSET));
1209 }
1210
1211 if (htab->plt_second_eh_frame != NULL
1212 && htab->plt_second_eh_frame->contents != NULL)
1213 {
1214 memcpy (htab->plt_second_eh_frame->contents,
1215 htab->non_lazy_plt->eh_frame_plt,
1216 htab->plt_second_eh_frame->size);
1217 bfd_put_32 (dynobj, htab->plt_second->size,
1218 (htab->plt_second_eh_frame->contents
1219 + PLT_FDE_LEN_OFFSET));
1220 }
1221
1222 if (htab->elf.dynamic_sections_created)
1223 {
1224 /* Add some entries to the .dynamic section. We fill in the
1225 values later, in elf_{i386,x86_64}_finish_dynamic_sections,
1226 but we must add the entries now so that we get the correct
1227 size for the .dynamic section. The DT_DEBUG entry is filled
1228 in by the dynamic linker and used by the debugger. */
1229#define add_dynamic_entry(TAG, VAL) \
1230 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
1231
1232 if (bfd_link_executable (info))
1233 {
1234 if (!add_dynamic_entry (DT_DEBUG, 0))
1235 return FALSE;
1236 }
1237
1238 if (htab->elf.splt->size != 0)
1239 {
1240 /* DT_PLTGOT is used by prelink even if there is no PLT
1241 relocation. */
1242 if (!add_dynamic_entry (DT_PLTGOT, 0))
1243 return FALSE;
1244 }
1245
1246 if (htab->elf.srelplt->size != 0)
1247 {
1248 if (!add_dynamic_entry (DT_PLTRELSZ, 0)
1249 || !add_dynamic_entry (DT_PLTREL, htab->dt_reloc)
1250 || !add_dynamic_entry (DT_JMPREL, 0))
1251 return FALSE;
1252 }
1253
1254 if (htab->tlsdesc_plt
1255 && (!add_dynamic_entry (DT_TLSDESC_PLT, 0)
1256 || !add_dynamic_entry (DT_TLSDESC_GOT, 0)))
1257 return FALSE;
1258
1259 if (relocs)
1260 {
1261 if (!add_dynamic_entry (htab->dt_reloc, 0)
1262 || !add_dynamic_entry (htab->dt_reloc_sz, 0)
1263 || !add_dynamic_entry (htab->dt_reloc_ent,
1264 htab->sizeof_reloc))
1265 return FALSE;
1266
1267 /* If any dynamic relocs apply to a read-only section,
1268 then we need a DT_TEXTREL entry. */
1269 if ((info->flags & DF_TEXTREL) == 0)
1270 elf_link_hash_traverse (&htab->elf,
1271 _bfd_x86_elf_readonly_dynrelocs,
1272 info);
1273
1274 if ((info->flags & DF_TEXTREL) != 0)
1275 {
1276 if (htab->readonly_dynrelocs_against_ifunc)
1277 {
1278 info->callbacks->einfo
1279 (_("%P%X: read-only segment has dynamic IFUNC relocations; recompile with -fPIC\n"));
1280 bfd_set_error (bfd_error_bad_value);
1281 return FALSE;
1282 }
1283
1284 if (!add_dynamic_entry (DT_TEXTREL, 0))
1285 return FALSE;
1286 }
1287 }
1288 if (htab->is_vxworks
1289 && !elf_vxworks_add_dynamic_entries (output_bfd, info))
1290 return FALSE;
1291 }
1292#undef add_dynamic_entry
1293
1294 return TRUE;
1295}
1296
0afcef53
L
1297bfd_boolean
1298_bfd_x86_elf_always_size_sections (bfd *output_bfd,
1299 struct bfd_link_info *info)
1300{
1301 asection *tls_sec = elf_hash_table (info)->tls_sec;
1302
1303 if (tls_sec)
1304 {
1305 struct elf_link_hash_entry *tlsbase;
1306
1307 tlsbase = elf_link_hash_lookup (elf_hash_table (info),
1308 "_TLS_MODULE_BASE_",
1309 FALSE, FALSE, FALSE);
1310
1311 if (tlsbase && tlsbase->type == STT_TLS)
1312 {
1313 struct elf_x86_link_hash_table *htab;
1314 struct bfd_link_hash_entry *bh = NULL;
1315 const struct elf_backend_data *bed
1316 = get_elf_backend_data (output_bfd);
1317
1318 htab = elf_x86_hash_table (info, bed->target_id);
1319 if (htab == NULL)
1320 return FALSE;
1321
1322 if (!(_bfd_generic_link_add_one_symbol
1323 (info, output_bfd, "_TLS_MODULE_BASE_", BSF_LOCAL,
1324 tls_sec, 0, NULL, FALSE,
1325 bed->collect, &bh)))
1326 return FALSE;
1327
1328 htab->tls_module_base = bh;
1329
1330 tlsbase = (struct elf_link_hash_entry *)bh;
1331 tlsbase->def_regular = 1;
1332 tlsbase->other = STV_HIDDEN;
1333 tlsbase->root.linker_def = 1;
1334 (*bed->elf_backend_hide_symbol) (info, tlsbase, TRUE);
1335 }
1336 }
1337
1338 return TRUE;
1339}
1340
1341void
1342_bfd_x86_elf_merge_symbol_attribute (struct elf_link_hash_entry *h,
1343 const Elf_Internal_Sym *isym,
1344 bfd_boolean definition,
1345 bfd_boolean dynamic ATTRIBUTE_UNUSED)
1346{
1347 if (definition)
1348 {
1349 struct elf_x86_link_hash_entry *eh
1350 = (struct elf_x86_link_hash_entry *) h;
1351 eh->def_protected = (ELF_ST_VISIBILITY (isym->st_other)
1352 == STV_PROTECTED);
1353 }
1354}
1355
1356/* Copy the extra info we tack onto an elf_link_hash_entry. */
1357
1358void
1359_bfd_x86_elf_copy_indirect_symbol (struct bfd_link_info *info,
1360 struct elf_link_hash_entry *dir,
1361 struct elf_link_hash_entry *ind)
1362{
1363 struct elf_x86_link_hash_entry *edir, *eind;
1364
1365 edir = (struct elf_x86_link_hash_entry *) dir;
1366 eind = (struct elf_x86_link_hash_entry *) ind;
1367
1368 if (eind->dyn_relocs != NULL)
1369 {
1370 if (edir->dyn_relocs != NULL)
1371 {
1372 struct elf_dyn_relocs **pp;
1373 struct elf_dyn_relocs *p;
1374
1375 /* Add reloc counts against the indirect sym to the direct sym
1376 list. Merge any entries against the same section. */
1377 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
1378 {
1379 struct elf_dyn_relocs *q;
1380
1381 for (q = edir->dyn_relocs; q != NULL; q = q->next)
1382 if (q->sec == p->sec)
1383 {
1384 q->pc_count += p->pc_count;
1385 q->count += p->count;
1386 *pp = p->next;
1387 break;
1388 }
1389 if (q == NULL)
1390 pp = &p->next;
1391 }
1392 *pp = edir->dyn_relocs;
1393 }
1394
1395 edir->dyn_relocs = eind->dyn_relocs;
1396 eind->dyn_relocs = NULL;
1397 }
1398
1399 if (ind->root.type == bfd_link_hash_indirect
1400 && dir->got.refcount <= 0)
1401 {
1402 edir->tls_type = eind->tls_type;
1403 eind->tls_type = GOT_UNKNOWN;
1404 }
1405
1406 /* Copy gotoff_ref so that elf_i386_adjust_dynamic_symbol will
1407 generate a R_386_COPY reloc. */
1408 edir->gotoff_ref |= eind->gotoff_ref;
1409
1410 edir->has_got_reloc |= eind->has_got_reloc;
1411 edir->has_non_got_reloc |= eind->has_non_got_reloc;
1412
1413 if (ELIMINATE_COPY_RELOCS
1414 && ind->root.type != bfd_link_hash_indirect
1415 && dir->dynamic_adjusted)
1416 {
1417 /* If called to transfer flags for a weakdef during processing
1418 of elf_adjust_dynamic_symbol, don't copy non_got_ref.
1419 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
1420 if (dir->versioned != versioned_hidden)
1421 dir->ref_dynamic |= ind->ref_dynamic;
1422 dir->ref_regular |= ind->ref_regular;
1423 dir->ref_regular_nonweak |= ind->ref_regular_nonweak;
1424 dir->needs_plt |= ind->needs_plt;
1425 dir->pointer_equality_needed |= ind->pointer_equality_needed;
1426 }
1427 else
1428 {
1429 if (eind->func_pointer_refcount > 0)
1430 {
1431 edir->func_pointer_refcount += eind->func_pointer_refcount;
1432 eind->func_pointer_refcount = 0;
1433 }
1434
1435 _bfd_elf_link_hash_copy_indirect (info, dir, ind);
1436 }
1437}
1438
1439/* Remove undefined weak symbol from the dynamic symbol table if it
1440 is resolved to 0. */
1441
1442bfd_boolean
1443_bfd_x86_elf_fixup_symbol (struct bfd_link_info *info,
1444 struct elf_link_hash_entry *h)
1445{
c5bce5c6
L
1446 if (h->dynindx != -1
1447 && UNDEFINED_WEAK_RESOLVED_TO_ZERO (info, elf_x86_hash_entry (h)))
0afcef53 1448 {
c5bce5c6
L
1449 h->dynindx = -1;
1450 _bfd_elf_strtab_delref (elf_hash_table (info)->dynstr,
1451 h->dynstr_index);
0afcef53
L
1452 }
1453 return TRUE;
1454}
1455
1456/* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */
1457
1458bfd_boolean
1459_bfd_x86_elf_hash_symbol (struct elf_link_hash_entry *h)
1460{
1461 if (h->plt.offset != (bfd_vma) -1
1462 && !h->def_regular
1463 && !h->pointer_equality_needed)
1464 return FALSE;
1465
1466 return _bfd_elf_hash_symbol (h);
1467}
1468
eeb2f20a
L
1469/* Adjust a symbol defined by a dynamic object and referenced by a
1470 regular object. The current definition is in some section of the
1471 dynamic object, but we're not including those sections. We have to
1472 change the definition to something the rest of the link can
1473 understand. */
1474
1475bfd_boolean
1476_bfd_x86_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
1477 struct elf_link_hash_entry *h)
1478{
1479 struct elf_x86_link_hash_table *htab;
1480 asection *s, *srel;
1481 struct elf_x86_link_hash_entry *eh;
1482 struct elf_dyn_relocs *p;
1483 const struct elf_backend_data *bed
1484 = get_elf_backend_data (info->output_bfd);
1485
1486 /* STT_GNU_IFUNC symbol must go through PLT. */
1487 if (h->type == STT_GNU_IFUNC)
1488 {
1489 /* All local STT_GNU_IFUNC references must be treate as local
1490 calls via local PLT. */
1491 if (h->ref_regular
1492 && SYMBOL_CALLS_LOCAL (info, h))
1493 {
1494 bfd_size_type pc_count = 0, count = 0;
1495 struct elf_dyn_relocs **pp;
1496
1497 eh = (struct elf_x86_link_hash_entry *) h;
1498 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1499 {
1500 pc_count += p->pc_count;
1501 p->count -= p->pc_count;
1502 p->pc_count = 0;
1503 count += p->count;
1504 if (p->count == 0)
1505 *pp = p->next;
1506 else
1507 pp = &p->next;
1508 }
1509
1510 if (pc_count || count)
1511 {
1512 h->non_got_ref = 1;
1513 if (pc_count)
1514 {
1515 /* Increment PLT reference count only for PC-relative
1516 references. */
1517 h->needs_plt = 1;
1518 if (h->plt.refcount <= 0)
1519 h->plt.refcount = 1;
1520 else
1521 h->plt.refcount += 1;
1522 }
1523 }
1524 }
1525
1526 if (h->plt.refcount <= 0)
1527 {
1528 h->plt.offset = (bfd_vma) -1;
1529 h->needs_plt = 0;
1530 }
1531 return TRUE;
1532 }
1533
1534 /* If this is a function, put it in the procedure linkage table. We
1535 will fill in the contents of the procedure linkage table later,
1536 when we know the address of the .got section. */
1537 if (h->type == STT_FUNC
1538 || h->needs_plt)
1539 {
1540 if (h->plt.refcount <= 0
1541 || SYMBOL_CALLS_LOCAL (info, h)
1542 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1543 && h->root.type == bfd_link_hash_undefweak))
1544 {
1545 /* This case can occur if we saw a PLT32 reloc in an input
1546 file, but the symbol was never referred to by a dynamic
1547 object, or if all references were garbage collected. In
1548 such a case, we don't actually need to build a procedure
1549 linkage table, and we can just do a PC32 reloc instead. */
1550 h->plt.offset = (bfd_vma) -1;
1551 h->needs_plt = 0;
1552 }
1553
1554 return TRUE;
1555 }
1556 else
1557 /* It's possible that we incorrectly decided a .plt reloc was needed
1558 * for an R_386_PC32/R_X86_64_PC32 reloc to a non-function sym in
1559 check_relocs. We can't decide accurately between function and
1560 non-function syms in check-relocs; Objects loaded later in
1561 the link may change h->type. So fix it now. */
1562 h->plt.offset = (bfd_vma) -1;
1563
1564 eh = (struct elf_x86_link_hash_entry *) h;
1565
1566 /* If this is a weak symbol, and there is a real definition, the
1567 processor independent code will have arranged for us to see the
1568 real definition first, and we can just use the same value. */
1569 if (h->u.weakdef != NULL)
1570 {
1571 BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined
1572 || h->u.weakdef->root.type == bfd_link_hash_defweak);
1573 h->root.u.def.section = h->u.weakdef->root.u.def.section;
1574 h->root.u.def.value = h->u.weakdef->root.u.def.value;
1575 if (ELIMINATE_COPY_RELOCS
1576 || info->nocopyreloc
1577 || SYMBOL_NO_COPYRELOC (info, eh))
1578 {
1579 /* NB: needs_copy is always 0 for i386. */
1580 h->non_got_ref = h->u.weakdef->non_got_ref;
1581 eh->needs_copy = h->u.weakdef->needs_copy;
1582 }
1583 return TRUE;
1584 }
1585
1586 /* This is a reference to a symbol defined by a dynamic object which
1587 is not a function. */
1588
1589 /* If we are creating a shared library, we must presume that the
1590 only references to the symbol are via the global offset table.
1591 For such cases we need not do anything here; the relocations will
1592 be handled correctly by relocate_section. */
1593 if (!bfd_link_executable (info))
1594 return TRUE;
1595
1596 /* If there are no references to this symbol that do not use the
1597 GOT nor R_386_GOTOFF relocation, we don't need to generate a copy
1598 reloc. NB: gotoff_ref is always 0 for x86-64. */
1599 if (!h->non_got_ref && !eh->gotoff_ref)
1600 return TRUE;
1601
1602 /* If -z nocopyreloc was given, we won't generate them either. */
1603 if (info->nocopyreloc || SYMBOL_NO_COPYRELOC (info, eh))
1604 {
1605 h->non_got_ref = 0;
1606 return TRUE;
1607 }
1608
1609 htab = elf_x86_hash_table (info, bed->target_id);
1610 if (htab == NULL)
1611 return FALSE;
1612
1613 /* If there aren't any dynamic relocs in read-only sections nor
1614 R_386_GOTOFF relocation, then we can keep the dynamic relocs and
1615 avoid the copy reloc. This doesn't work on VxWorks, where we can
1616 not have dynamic relocations (other than copy and jump slot
1617 relocations) in an executable. */
1618 if (ELIMINATE_COPY_RELOCS
1619 && (bed->target_id == X86_64_ELF_DATA
1620 || (!eh->gotoff_ref
1621 && !htab->is_vxworks)))
1622 {
1623 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1624 {
1625 s = p->sec->output_section;
1626 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1627 break;
1628 }
1629
1630 /* If we didn't find any dynamic relocs in read-only sections,
1631 then we'll be keeping the dynamic relocs and avoiding the copy
1632 reloc. */
1633 if (p == NULL)
1634 {
1635 h->non_got_ref = 0;
1636 return TRUE;
1637 }
1638 }
1639
1640 /* We must allocate the symbol in our .dynbss section, which will
1641 become part of the .bss section of the executable. There will be
1642 an entry for this symbol in the .dynsym section. The dynamic
1643 object will contain position independent code, so all references
1644 from the dynamic object to this symbol will go through the global
1645 offset table. The dynamic linker will use the .dynsym entry to
1646 determine the address it must put in the global offset table, so
1647 both the dynamic object and the regular object will refer to the
1648 same memory location for the variable. */
1649
1650 /* We must generate a R_386_COPY/R_X86_64_COPY reloc to tell the
1651 dynamic linker to copy the initial value out of the dynamic object
1652 and into the runtime process image. */
1653 if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
1654 {
1655 s = htab->elf.sdynrelro;
1656 srel = htab->elf.sreldynrelro;
1657 }
1658 else
1659 {
1660 s = htab->elf.sdynbss;
1661 srel = htab->elf.srelbss;
1662 }
1663 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
1664 {
503294e7 1665 srel->size += htab->sizeof_reloc;
eeb2f20a
L
1666 h->needs_copy = 1;
1667 }
1668
1669 return _bfd_elf_adjust_dynamic_copy (info, h, s);
1670}
1671
6999821f
L
1672/* Return TRUE if a symbol is referenced locally. It is similar to
1673 SYMBOL_REFERENCES_LOCAL, but it also checks version script. It
1674 works in check_relocs. */
1675
1676bfd_boolean
1677_bfd_x86_elf_link_symbol_references_local (struct bfd_link_info *info,
1678 struct elf_link_hash_entry *h)
1679{
0a27fed7
L
1680 struct elf_x86_link_hash_entry *eh = elf_x86_hash_entry (h);
1681 struct elf_x86_link_hash_table *htab
1682 = (struct elf_x86_link_hash_table *) info->hash;
6999821f
L
1683
1684 if (eh->local_ref > 1)
1685 return TRUE;
1686
1687 if (eh->local_ref == 1)
1688 return FALSE;
1689
1690 /* Unversioned symbols defined in regular objects can be forced local
0a27fed7
L
1691 by linker version script. A weak undefined symbol is forced local
1692 if
1693 1. It has non-default visibility. Or
8fbf0ba1 1694 2. When building executable, there is no dynamic linker. Or
0a27fed7
L
1695 3. or "-z nodynamic-undefined-weak" is used.
1696 */
6999821f 1697 if (SYMBOL_REFERENCES_LOCAL (info, h)
0a27fed7
L
1698 || (h->root.type == bfd_link_hash_undefweak
1699 && (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1700 || (bfd_link_executable (info)
8fbf0ba1 1701 && htab->interp == NULL)
0a27fed7 1702 || info->dynamic_undefined_weak == 0))
6999821f
L
1703 || ((h->def_regular || ELF_COMMON_DEF_P (h))
1704 && h->versioned == unversioned
1705 && info->version_info != NULL
1706 && bfd_hide_sym_by_version (info->version_info,
1707 h->root.root.string)))
1708 {
1709 eh->local_ref = 2;
1710 return TRUE;
1711 }
1712
1713 eh->local_ref = 1;
1714 return FALSE;
1715}
1716
4f501a24
L
1717/* Return the section that should be marked against GC for a given
1718 relocation. */
1719
1720asection *
1721_bfd_x86_elf_gc_mark_hook (asection *sec,
1722 struct bfd_link_info *info,
1723 Elf_Internal_Rela *rel,
1724 struct elf_link_hash_entry *h,
1725 Elf_Internal_Sym *sym)
1726{
1727 /* Compiler should optimize this out. */
1728 if (((unsigned int) R_X86_64_GNU_VTINHERIT
1729 != (unsigned int) R_386_GNU_VTINHERIT)
1730 || ((unsigned int) R_X86_64_GNU_VTENTRY
1731 != (unsigned int) R_386_GNU_VTENTRY))
1732 abort ();
1733
1734 if (h != NULL)
1735 switch (ELF32_R_TYPE (rel->r_info))
1736 {
1737 case R_X86_64_GNU_VTINHERIT:
1738 case R_X86_64_GNU_VTENTRY:
1739 return NULL;
1740 }
1741
1742 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
1743}
1744
f493882d
L
1745static bfd_vma
1746elf_i386_get_plt_got_vma (struct elf_x86_plt *plt_p ATTRIBUTE_UNUSED,
1747 bfd_vma off,
1748 bfd_vma offset ATTRIBUTE_UNUSED,
1749 bfd_vma got_addr)
1750{
1751 return got_addr + off;
1752}
1753
1754static bfd_vma
1755elf_x86_64_get_plt_got_vma (struct elf_x86_plt *plt_p,
1756 bfd_vma off,
1757 bfd_vma offset,
1758 bfd_vma got_addr ATTRIBUTE_UNUSED)
1759{
1760 return plt_p->sec->vma + offset + off + plt_p->plt_got_insn_size;
1761}
1762
1763static bfd_boolean
1764elf_i386_valid_plt_reloc_p (unsigned int type)
1765{
1766 return (type == R_386_JUMP_SLOT
1767 || type == R_386_GLOB_DAT
1768 || type == R_386_IRELATIVE);
1769}
1770
1771static bfd_boolean
1772elf_x86_64_valid_plt_reloc_p (unsigned int type)
1773{
1774 return (type == R_X86_64_JUMP_SLOT
1775 || type == R_X86_64_GLOB_DAT
1776 || type == R_X86_64_IRELATIVE);
1777}
1778
1779long
1780_bfd_x86_elf_get_synthetic_symtab (bfd *abfd,
1781 long count,
1782 long relsize,
1783 bfd_vma got_addr,
1784 struct elf_x86_plt plts[],
1785 asymbol **dynsyms,
1786 asymbol **ret)
1787{
1788 long size, i, n, len;
1789 int j;
1790 unsigned int plt_got_offset, plt_entry_size;
1791 asymbol *s;
1792 bfd_byte *plt_contents;
1793 long dynrelcount;
1794 arelent **dynrelbuf, *p;
1795 char *names;
1796 const struct elf_backend_data *bed;
1797 bfd_vma (*get_plt_got_vma) (struct elf_x86_plt *, bfd_vma, bfd_vma,
1798 bfd_vma);
1799 bfd_boolean (*valid_plt_reloc_p) (unsigned int);
1800
1801 if (count == 0)
1802 return -1;
1803
1804 dynrelbuf = (arelent **) bfd_malloc (relsize);
1805 if (dynrelbuf == NULL)
1806 return -1;
1807
1808 dynrelcount = bfd_canonicalize_dynamic_reloc (abfd, dynrelbuf,
1809 dynsyms);
b69e9267 1810 if (dynrelcount <= 0)
94670f6c 1811 return -1;
f493882d
L
1812
1813 /* Sort the relocs by address. */
1814 qsort (dynrelbuf, dynrelcount, sizeof (arelent *),
1815 _bfd_x86_elf_compare_relocs);
1816
1817 size = count * sizeof (asymbol);
1818
1819 /* Allocate space for @plt suffixes. */
1820 n = 0;
1821 for (i = 0; i < dynrelcount; i++)
1822 {
1823 p = dynrelbuf[i];
1824 size += strlen ((*p->sym_ptr_ptr)->name) + sizeof ("@plt");
1825 if (p->addend != 0)
1826 size += sizeof ("+0x") - 1 + 8 + 8 * ABI_64_P (abfd);
1827 }
1828
1829 s = *ret = (asymbol *) bfd_zmalloc (size);
1830 if (s == NULL)
1831 goto bad_return;
1832
1833 bed = get_elf_backend_data (abfd);
1834
1835 if (bed->target_id == X86_64_ELF_DATA)
1836 {
1837 get_plt_got_vma = elf_x86_64_get_plt_got_vma;
1838 valid_plt_reloc_p = elf_x86_64_valid_plt_reloc_p;
1839 }
1840 else
1841 {
1842 get_plt_got_vma = elf_i386_get_plt_got_vma;
1843 valid_plt_reloc_p = elf_i386_valid_plt_reloc_p;
1844 if (got_addr)
1845 {
1846 /* Check .got.plt and then .got to get the _GLOBAL_OFFSET_TABLE_
1847 address. */
1848 asection *sec = bfd_get_section_by_name (abfd, ".got.plt");
1849 if (sec != NULL)
1850 got_addr = sec->vma;
1851 else
1852 {
1853 sec = bfd_get_section_by_name (abfd, ".got");
1854 if (sec != NULL)
1855 got_addr = sec->vma;
1856 }
1857
1858 if (got_addr == (bfd_vma) -1)
1859 goto bad_return;
1860 }
1861 }
1862
1863 /* Check for each PLT section. */
1864 names = (char *) (s + count);
1865 size = 0;
1866 n = 0;
1867 for (j = 0; plts[j].name != NULL; j++)
1868 if ((plt_contents = plts[j].contents) != NULL)
1869 {
1870 long k;
1871 bfd_vma offset;
1872 asection *plt;
1873 struct elf_x86_plt *plt_p = &plts[j];
1874
1875 plt_got_offset = plt_p->plt_got_offset;
1876 plt_entry_size = plt_p->plt_entry_size;
1877
1878 plt = plt_p->sec;
1879
1880 if ((plt_p->type & plt_lazy))
1881 {
1882 /* Skip PLT0 in lazy PLT. */
1883 k = 1;
1884 offset = plt_entry_size;
1885 }
1886 else
1887 {
1888 k = 0;
1889 offset = 0;
1890 }
1891
1892 /* Check each PLT entry against dynamic relocations. */
1893 for (; k < plt_p->count; k++)
1894 {
1895 int off;
1896 bfd_vma got_vma;
1897 long min, max, mid;
1898
1899 /* Get the GOT offset for i386 or the PC-relative offset
1900 for x86-64, a signed 32-bit integer. */
1901 off = H_GET_32 (abfd, (plt_contents + offset
1902 + plt_got_offset));
1903 got_vma = get_plt_got_vma (plt_p, off, offset, got_addr);
1904
1905 /* Binary search. */
1906 p = dynrelbuf[0];
1907 min = 0;
1908 max = dynrelcount;
1909 while ((min + 1) < max)
1910 {
1911 arelent *r;
1912
1913 mid = (min + max) / 2;
1914 r = dynrelbuf[mid];
1915 if (got_vma > r->address)
1916 min = mid;
1917 else if (got_vma < r->address)
1918 max = mid;
1919 else
1920 {
1921 p = r;
1922 break;
1923 }
1924 }
1925
1926 /* Skip unknown relocation. PR 17512: file: bc9d6cf5. */
1927 if (got_vma == p->address
1928 && p->howto != NULL
1929 && valid_plt_reloc_p (p->howto->type))
1930 {
1931 *s = **p->sym_ptr_ptr;
1932 /* Undefined syms won't have BSF_LOCAL or BSF_GLOBAL
1933 set. Since we are defining a symbol, ensure one
1934 of them is set. */
1935 if ((s->flags & BSF_LOCAL) == 0)
1936 s->flags |= BSF_GLOBAL;
1937 s->flags |= BSF_SYNTHETIC;
1938 /* This is no longer a section symbol. */
1939 s->flags &= ~BSF_SECTION_SYM;
1940 s->section = plt;
1941 s->the_bfd = plt->owner;
1942 s->value = offset;
1943 s->udata.p = NULL;
1944 s->name = names;
1945 len = strlen ((*p->sym_ptr_ptr)->name);
1946 memcpy (names, (*p->sym_ptr_ptr)->name, len);
1947 names += len;
1948 if (p->addend != 0)
1949 {
1950 char buf[30], *a;
1951
1952 memcpy (names, "+0x", sizeof ("+0x") - 1);
1953 names += sizeof ("+0x") - 1;
1954 bfd_sprintf_vma (abfd, buf, p->addend);
1955 for (a = buf; *a == '0'; ++a)
1956 ;
1957 size = strlen (a);
1958 memcpy (names, a, size);
1959 names += size;
1960 }
1961 memcpy (names, "@plt", sizeof ("@plt"));
1962 names += sizeof ("@plt");
1963 n++;
1964 s++;
1965 }
1966 offset += plt_entry_size;
1967 }
1968 }
1969
1970 /* PLT entries with R_386_TLS_DESC relocations are skipped. */
1971 if (n == 0)
1972 {
1973bad_return:
1974 count = -1;
1975 }
1976 else
1977 count = n;
1978
1979 for (j = 0; plts[j].name != NULL; j++)
1980 if (plts[j].contents != NULL)
1981 free (plts[j].contents);
1982
1983 free (dynrelbuf);
1984
1985 return count;
1986}
1987
0afcef53
L
1988/* Parse x86 GNU properties. */
1989
1990enum elf_property_kind
1991_bfd_x86_elf_parse_gnu_properties (bfd *abfd, unsigned int type,
1992 bfd_byte *ptr, unsigned int datasz)
1993{
1994 elf_property *prop;
1995
1996 switch (type)
1997 {
1998 case GNU_PROPERTY_X86_ISA_1_USED:
1999 case GNU_PROPERTY_X86_ISA_1_NEEDED:
2000 case GNU_PROPERTY_X86_FEATURE_1_AND:
2001 if (datasz != 4)
2002 {
2003 _bfd_error_handler
2004 ((type == GNU_PROPERTY_X86_ISA_1_USED
2005 ? _("error: %B: <corrupt x86 ISA used size: 0x%x>")
2006 : (type == GNU_PROPERTY_X86_ISA_1_NEEDED
2007 ? _("error: %B: <corrupt x86 ISA needed size: 0x%x>")
2008 : _("error: %B: <corrupt x86 feature size: 0x%x>"))),
2009 abfd, datasz);
2010 return property_corrupt;
2011 }
2012 prop = _bfd_elf_get_property (abfd, type, datasz);
2013 /* Combine properties of the same type. */
2014 prop->u.number |= bfd_h_get_32 (abfd, ptr);
2015 prop->pr_kind = property_number;
2016 break;
2017
2018 default:
2019 return property_ignored;
2020 }
2021
2022 return property_number;
2023}
2024
2025/* Merge x86 GNU property BPROP with APROP. If APROP isn't NULL,
2026 return TRUE if APROP is updated. Otherwise, return TRUE if BPROP
2027 should be merged with ABFD. */
2028
2029bfd_boolean
2030_bfd_x86_elf_merge_gnu_properties (struct bfd_link_info *info,
2031 bfd *abfd ATTRIBUTE_UNUSED,
2032 elf_property *aprop,
2033 elf_property *bprop)
2034{
2035 unsigned int number, features;
2036 bfd_boolean updated = FALSE;
2037 unsigned int pr_type = aprop != NULL ? aprop->pr_type : bprop->pr_type;
2038
2039 switch (pr_type)
2040 {
2041 case GNU_PROPERTY_X86_ISA_1_USED:
2042 case GNU_PROPERTY_X86_ISA_1_NEEDED:
2043 if (aprop != NULL && bprop != NULL)
2044 {
2045 number = aprop->u.number;
2046 aprop->u.number = number | bprop->u.number;
2047 updated = number != (unsigned int) aprop->u.number;
2048 }
2049 else
2050 {
2051 /* Return TRUE if APROP is NULL to indicate that BPROP should
2052 be added to ABFD. */
2053 updated = aprop == NULL;
2054 }
2055 break;
2056
2057 case GNU_PROPERTY_X86_FEATURE_1_AND:
2058 /* Only one of APROP and BPROP can be NULL:
2059 1. APROP & BPROP when both APROP and BPROP aren't NULL.
2060 2. If APROP is NULL, remove x86 feature.
2061 3. Otherwise, do nothing.
2062 */
2063 if (aprop != NULL && bprop != NULL)
2064 {
2065 features = 0;
2066 if (info->ibt)
2067 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2068 if (info->shstk)
2069 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2070 number = aprop->u.number;
2071 /* Add GNU_PROPERTY_X86_FEATURE_1_IBT and
2072 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2073 aprop->u.number = (number & bprop->u.number) | features;
2074 updated = number != (unsigned int) aprop->u.number;
2075 /* Remove the property if all feature bits are cleared. */
2076 if (aprop->u.number == 0)
2077 aprop->pr_kind = property_remove;
2078 }
2079 else
2080 {
2081 features = 0;
2082 if (info->ibt)
2083 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2084 if (info->shstk)
2085 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2086 if (features)
2087 {
2088 /* Add GNU_PROPERTY_X86_FEATURE_1_IBT and
2089 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2090 if (aprop != NULL)
2091 {
2092 number = aprop->u.number;
2093 aprop->u.number = number | features;
2094 updated = number != (unsigned int) aprop->u.number;
2095 }
2096 else
2097 {
2098 bprop->u.number |= features;
2099 updated = TRUE;
2100 }
2101 }
2102 else if (aprop != NULL)
2103 {
2104 aprop->pr_kind = property_remove;
2105 updated = TRUE;
2106 }
2107 }
2108 break;
2109
2110 default:
2111 /* Never should happen. */
2112 abort ();
2113 }
2114
2115 return updated;
2116}
a6798bab
L
2117
2118/* Set up x86 GNU properties. Return the first relocatable ELF input
2119 with GNU properties if found. Otherwise, return NULL. */
2120
2121bfd *
2122_bfd_x86_elf_link_setup_gnu_properties
1de031c8 2123 (struct bfd_link_info *info, struct elf_x86_init_table *init_table)
a6798bab
L
2124{
2125 bfd_boolean normal_target;
2126 bfd_boolean lazy_plt;
2127 asection *sec, *pltsec;
2128 bfd *dynobj;
2129 bfd_boolean use_ibt_plt;
2130 unsigned int plt_alignment, features;
2131 struct elf_x86_link_hash_table *htab;
2132 bfd *pbfd;
2133 bfd *ebfd = NULL;
2134 elf_property *prop;
2135 const struct elf_backend_data *bed;
2136 unsigned int class_align = ABI_64_P (info->output_bfd) ? 3 : 2;
2137 unsigned int got_align;
2138
2139 features = 0;
2140 if (info->ibt)
2141 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2142 if (info->shstk)
2143 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2144
2145 /* Find a normal input file with GNU property note. */
2146 for (pbfd = info->input_bfds;
2147 pbfd != NULL;
2148 pbfd = pbfd->link.next)
2149 if (bfd_get_flavour (pbfd) == bfd_target_elf_flavour
2150 && bfd_count_sections (pbfd) != 0)
2151 {
2152 ebfd = pbfd;
2153
2154 if (elf_properties (pbfd) != NULL)
2155 break;
2156 }
2157
2158 if (ebfd != NULL && features)
2159 {
2160 /* If features is set, add GNU_PROPERTY_X86_FEATURE_1_IBT and
2161 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2162 prop = _bfd_elf_get_property (ebfd,
2163 GNU_PROPERTY_X86_FEATURE_1_AND,
2164 4);
2165 prop->u.number |= features;
2166 prop->pr_kind = property_number;
2167
2168 /* Create the GNU property note section if needed. */
2169 if (pbfd == NULL)
2170 {
2171 sec = bfd_make_section_with_flags (ebfd,
2172 NOTE_GNU_PROPERTY_SECTION_NAME,
2173 (SEC_ALLOC
2174 | SEC_LOAD
2175 | SEC_IN_MEMORY
2176 | SEC_READONLY
2177 | SEC_HAS_CONTENTS
2178 | SEC_DATA));
2179 if (sec == NULL)
2180 info->callbacks->einfo (_("%F: failed to create GNU property section\n"));
2181
2182 if (!bfd_set_section_alignment (ebfd, sec, class_align))
2183 {
2184error_alignment:
2185 info->callbacks->einfo (_("%F%A: failed to align section\n"),
2186 sec);
2187 }
2188
2189 elf_section_type (sec) = SHT_NOTE;
2190 }
2191 }
2192
2193 pbfd = _bfd_elf_link_setup_gnu_properties (info);
2194
a6798bab
L
2195 bed = get_elf_backend_data (info->output_bfd);
2196
2197 htab = elf_x86_hash_table (info, bed->target_id);
2198 if (htab == NULL)
2199 return pbfd;
2200
1de031c8
L
2201 htab->is_vxworks = init_table->is_vxworks;
2202 htab->r_info = init_table->r_info;
2203 htab->r_sym = init_table->r_sym;
7a382c1c
L
2204
2205 if (bfd_link_relocatable (info))
2206 return pbfd;
eeb2f20a 2207
a6798bab
L
2208 use_ibt_plt = info->ibtplt || info->ibt;
2209 if (!use_ibt_plt && pbfd != NULL)
2210 {
2211 /* Check if GNU_PROPERTY_X86_FEATURE_1_IBT is on. */
2212 elf_property_list *p;
2213
2214 /* The property list is sorted in order of type. */
2215 for (p = elf_properties (pbfd); p; p = p->next)
2216 {
2217 if (GNU_PROPERTY_X86_FEATURE_1_AND == p->property.pr_type)
2218 {
2219 use_ibt_plt = !!(p->property.u.number
2220 & GNU_PROPERTY_X86_FEATURE_1_IBT);
2221 break;
2222 }
2223 else if (GNU_PROPERTY_X86_FEATURE_1_AND < p->property.pr_type)
2224 break;
2225 }
2226 }
2227
2228 dynobj = htab->elf.dynobj;
2229
2230 /* Set htab->elf.dynobj here so that there is no need to check and
2231 set it in check_relocs. */
2232 if (dynobj == NULL)
2233 {
2234 if (pbfd != NULL)
2235 {
2236 htab->elf.dynobj = pbfd;
2237 dynobj = pbfd;
2238 }
2239 else
2240 {
2241 bfd *abfd;
2242
2243 /* Find a normal input file to hold linker created
2244 sections. */
2245 for (abfd = info->input_bfds;
2246 abfd != NULL;
2247 abfd = abfd->link.next)
2248 if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
2249 && (abfd->flags
2250 & (DYNAMIC | BFD_LINKER_CREATED | BFD_PLUGIN)) == 0)
2251 {
2252 htab->elf.dynobj = abfd;
2253 dynobj = abfd;
2254 break;
2255 }
2256 }
2257 }
2258
2259 /* Even when lazy binding is disabled by "-z now", the PLT0 entry may
2260 still be used with LD_AUDIT or LD_PROFILE if PLT entry is used for
2261 canonical function address. */
2262 htab->plt.has_plt0 = 1;
1de031c8 2263 normal_target = init_table->normal_target;
a6798bab
L
2264
2265 if (normal_target)
2266 {
2267 if (use_ibt_plt)
2268 {
1de031c8
L
2269 htab->lazy_plt = init_table->lazy_ibt_plt;
2270 htab->non_lazy_plt = init_table->non_lazy_ibt_plt;
a6798bab
L
2271 }
2272 else
2273 {
1de031c8
L
2274 htab->lazy_plt = init_table->lazy_plt;
2275 htab->non_lazy_plt = init_table->non_lazy_plt;
a6798bab
L
2276 }
2277 }
2278 else
2279 {
1de031c8 2280 htab->lazy_plt = init_table->lazy_plt;
a6798bab
L
2281 htab->non_lazy_plt = NULL;
2282 }
2283
2284 pltsec = htab->elf.splt;
2285
2286 /* If the non-lazy PLT is available, use it for all PLT entries if
2287 there are no PLT0 or no .plt section. */
2288 if (htab->non_lazy_plt != NULL
2289 && (!htab->plt.has_plt0 || pltsec == NULL))
2290 {
2291 lazy_plt = FALSE;
2292 if (bfd_link_pic (info))
2293 htab->plt.plt_entry = htab->non_lazy_plt->pic_plt_entry;
2294 else
2295 htab->plt.plt_entry = htab->non_lazy_plt->plt_entry;
2296 htab->plt.plt_entry_size = htab->non_lazy_plt->plt_entry_size;
2297 htab->plt.plt_got_offset = htab->non_lazy_plt->plt_got_offset;
2298 htab->plt.plt_got_insn_size
2299 = htab->non_lazy_plt->plt_got_insn_size;
2300 htab->plt.eh_frame_plt_size
2301 = htab->non_lazy_plt->eh_frame_plt_size;
2302 htab->plt.eh_frame_plt = htab->non_lazy_plt->eh_frame_plt;
2303 }
2304 else
2305 {
2306 lazy_plt = TRUE;
2307 if (bfd_link_pic (info))
2308 {
2309 htab->plt.plt0_entry = htab->lazy_plt->pic_plt0_entry;
2310 htab->plt.plt_entry = htab->lazy_plt->pic_plt_entry;
2311 }
2312 else
2313 {
2314 htab->plt.plt0_entry = htab->lazy_plt->plt0_entry;
2315 htab->plt.plt_entry = htab->lazy_plt->plt_entry;
2316 }
2317 htab->plt.plt_entry_size = htab->lazy_plt->plt_entry_size;
2318 htab->plt.plt_got_offset = htab->lazy_plt->plt_got_offset;
2319 htab->plt.plt_got_insn_size
2320 = htab->lazy_plt->plt_got_insn_size;
2321 htab->plt.eh_frame_plt_size
2322 = htab->lazy_plt->eh_frame_plt_size;
2323 htab->plt.eh_frame_plt = htab->lazy_plt->eh_frame_plt;
2324 }
2325
2326 /* Return if there are no normal input files. */
2327 if (dynobj == NULL)
2328 return pbfd;
2329
eeb2f20a 2330 if (htab->is_vxworks
a6798bab
L
2331 && !elf_vxworks_create_dynamic_sections (dynobj, info,
2332 &htab->srelplt2))
2333 {
2334 info->callbacks->einfo (_("%F: failed to create VxWorks dynamic sections\n"));
2335 return pbfd;
2336 }
2337
2338 /* Since create_dynamic_sections isn't always called, but GOT
2339 relocations need GOT relocations, create them here so that we
2340 don't need to do it in check_relocs. */
2341 if (htab->elf.sgot == NULL
2342 && !_bfd_elf_create_got_section (dynobj, info))
2343 info->callbacks->einfo (_("%F: failed to create GOT sections\n"));
2344
2345 got_align = (bed->target_id == X86_64_ELF_DATA) ? 3 : 2;
2346
2347 /* Align .got and .got.plt sections to their entry size. Do it here
2348 instead of in create_dynamic_sections so that they are always
2349 properly aligned even if create_dynamic_sections isn't called. */
2350 sec = htab->elf.sgot;
2351 if (!bfd_set_section_alignment (dynobj, sec, got_align))
2352 goto error_alignment;
2353
2354 sec = htab->elf.sgotplt;
2355 if (!bfd_set_section_alignment (dynobj, sec, got_align))
2356 goto error_alignment;
2357
2358 /* Create the ifunc sections here so that check_relocs can be
2359 simplified. */
2360 if (!_bfd_elf_create_ifunc_sections (dynobj, info))
2361 info->callbacks->einfo (_("%F: failed to create ifunc sections\n"));
2362
2363 plt_alignment = bfd_log2 (htab->plt.plt_entry_size);
2364
2365 if (pltsec != NULL)
2366 {
2367 /* Whe creating executable, set the contents of the .interp
2368 section to the interpreter. */
2369 if (bfd_link_executable (info) && !info->nointerp)
2370 {
2371 asection *s = bfd_get_linker_section (dynobj, ".interp");
2372 if (s == NULL)
2373 abort ();
2374 s->size = htab->dynamic_interpreter_size;
2375 s->contents = (unsigned char *) htab->dynamic_interpreter;
2376 htab->interp = s;
2377 }
2378
2379 /* Don't change PLT section alignment for NaCl since it uses
2380 64-byte PLT entry and sets PLT section alignment to 32
2381 bytes. Don't create additional PLT sections for NaCl. */
2382 if (normal_target)
2383 {
2384 flagword pltflags = (bed->dynamic_sec_flags
2385 | SEC_ALLOC
2386 | SEC_CODE
2387 | SEC_LOAD
2388 | SEC_READONLY);
2389 unsigned int non_lazy_plt_alignment
2390 = bfd_log2 (htab->non_lazy_plt->plt_entry_size);
2391
2392 sec = pltsec;
2393 if (!bfd_set_section_alignment (sec->owner, sec,
2394 plt_alignment))
2395 goto error_alignment;
2396
2397 /* Create the GOT procedure linkage table. */
2398 sec = bfd_make_section_anyway_with_flags (dynobj,
2399 ".plt.got",
2400 pltflags);
2401 if (sec == NULL)
2402 info->callbacks->einfo (_("%F: failed to create GOT PLT section\n"));
2403
2404 if (!bfd_set_section_alignment (dynobj, sec,
2405 non_lazy_plt_alignment))
2406 goto error_alignment;
2407
2408 htab->plt_got = sec;
2409
2410 if (lazy_plt)
2411 {
2412 sec = NULL;
2413
2414 if (use_ibt_plt)
2415 {
2416 /* Create the second PLT for Intel IBT support. IBT
2417 PLT is supported only for non-NaCl target and is
2418 is needed only for lazy binding. */
2419 sec = bfd_make_section_anyway_with_flags (dynobj,
2420 ".plt.sec",
2421 pltflags);
2422 if (sec == NULL)
2423 info->callbacks->einfo (_("%F: failed to create IBT-enabled PLT section\n"));
2424
2425 if (!bfd_set_section_alignment (dynobj, sec,
2426 plt_alignment))
2427 goto error_alignment;
2428 }
2429 else if (info->bndplt && ABI_64_P (dynobj))
2430 {
2431 /* Create the second PLT for Intel MPX support. MPX
2432 PLT is supported only for non-NaCl target in 64-bit
2433 mode and is needed only for lazy binding. */
2434 sec = bfd_make_section_anyway_with_flags (dynobj,
2435 ".plt.sec",
2436 pltflags);
2437 if (sec == NULL)
2438 info->callbacks->einfo (_("%F: failed to create BND PLT section\n"));
2439
2440 if (!bfd_set_section_alignment (dynobj, sec,
2441 non_lazy_plt_alignment))
2442 goto error_alignment;
2443 }
2444
2445 htab->plt_second = sec;
2446 }
2447 }
2448
2449 if (!info->no_ld_generated_unwind_info)
2450 {
2451 flagword flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY
2452 | SEC_HAS_CONTENTS | SEC_IN_MEMORY
2453 | SEC_LINKER_CREATED);
2454
2455 sec = bfd_make_section_anyway_with_flags (dynobj,
2456 ".eh_frame",
2457 flags);
2458 if (sec == NULL)
2459 info->callbacks->einfo (_("%F: failed to create PLT .eh_frame section\n"));
2460
2461 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2462 goto error_alignment;
2463
2464 htab->plt_eh_frame = sec;
2465
2466 if (htab->plt_got != NULL)
2467 {
2468 sec = bfd_make_section_anyway_with_flags (dynobj,
2469 ".eh_frame",
2470 flags);
2471 if (sec == NULL)
2472 info->callbacks->einfo (_("%F: failed to create GOT PLT .eh_frame section\n"));
2473
2474 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2475 goto error_alignment;
2476
2477 htab->plt_got_eh_frame = sec;
2478 }
2479
2480 if (htab->plt_second != NULL)
2481 {
2482 sec = bfd_make_section_anyway_with_flags (dynobj,
2483 ".eh_frame",
2484 flags);
2485 if (sec == NULL)
2486 info->callbacks->einfo (_("%F: failed to create the second PLT .eh_frame section\n"));
2487
2488 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2489 goto error_alignment;
2490
2491 htab->plt_second_eh_frame = sec;
2492 }
2493 }
2494 }
2495
2496 if (normal_target)
2497 {
2498 /* The .iplt section is used for IFUNC symbols in static
2499 executables. */
2500 sec = htab->elf.iplt;
2501 if (sec != NULL
2502 && !bfd_set_section_alignment (sec->owner, sec,
2503 plt_alignment))
2504 goto error_alignment;
2505 }
2506
2507 return pbfd;
2508}
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