x86: Properly handle __ehdr_start
[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
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))
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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 }
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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
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539/* Find any dynamic relocs that apply to read-only sections. */
540
541bfd_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
b9ce864c
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577/* Allocate space in .plt, .got and associated reloc sections for
578 local dynamic relocs. */
579
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580static bfd_boolean
581elf_x86_allocate_local_dynreloc (void **slot, void *inf)
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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
5e2ac45d 593 return elf_x86_allocate_dynrelocs (h, inf);
b9ce864c
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594}
595
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596/* Find and/or create a hash entry for local symbol. */
597
598struct 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
641struct 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
692hashval_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
702int
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
765e526c
L
715static void
716elf_x86_link_hash_table_free (bfd *obfd)
0afcef53
L
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
5e2ac45d
L
728static bfd_boolean
729elf_i386_is_reloc_section (const char *secname)
730{
731 return CONST_STRNEQ (secname, ".rel");
732}
733
5e2ac45d
L
734static bfd_boolean
735elf_x86_64_is_reloc_section (const char *secname)
736{
737 return CONST_STRNEQ (secname, ".rela");
738}
5e2ac45d 739
765e526c
L
740/* Create an x86 ELF linker hash table. */
741
742struct bfd_link_hash_table *
743_bfd_x86_elf_link_hash_table_create (bfd *abfd)
744{
745 struct elf_x86_link_hash_table *ret;
746 const struct elf_backend_data *bed;
747 bfd_size_type amt = sizeof (struct elf_x86_link_hash_table);
748
749 ret = (struct elf_x86_link_hash_table *) bfd_zmalloc (amt);
750 if (ret == NULL)
751 return NULL;
752
753 bed = get_elf_backend_data (abfd);
754 if (!_bfd_elf_link_hash_table_init (&ret->elf, abfd,
755 _bfd_x86_elf_link_hash_newfunc,
756 sizeof (struct elf_x86_link_hash_entry),
757 bed->target_id))
758 {
759 free (ret);
760 return NULL;
761 }
762
5e2ac45d
L
763 if (bed->target_id == X86_64_ELF_DATA)
764 {
5e2ac45d
L
765 ret->is_reloc_section = elf_x86_64_is_reloc_section;
766 ret->dt_reloc = DT_RELA;
767 ret->dt_reloc_sz = DT_RELASZ;
768 ret->dt_reloc_ent = DT_RELAENT;
769 ret->got_entry_size = 8;
f04bdfa7 770 ret->tls_get_addr = "__tls_get_addr";
5e2ac45d 771 }
765e526c
L
772 if (ABI_64_P (abfd))
773 {
503294e7 774 ret->sizeof_reloc = sizeof (Elf64_External_Rela);
765e526c
L
775 ret->pointer_r_type = R_X86_64_64;
776 ret->dynamic_interpreter = ELF64_DYNAMIC_INTERPRETER;
777 ret->dynamic_interpreter_size = sizeof ELF64_DYNAMIC_INTERPRETER;
765e526c
L
778 }
779 else
765e526c 780 {
5b86dbf4 781 if (bed->target_id == X86_64_ELF_DATA)
765e526c 782 {
503294e7 783 ret->sizeof_reloc = sizeof (Elf32_External_Rela);
765e526c
L
784 ret->pointer_r_type = R_X86_64_32;
785 ret->dynamic_interpreter = ELFX32_DYNAMIC_INTERPRETER;
786 ret->dynamic_interpreter_size
787 = sizeof ELFX32_DYNAMIC_INTERPRETER;
765e526c
L
788 }
789 else
790 {
5e2ac45d
L
791 ret->is_reloc_section = elf_i386_is_reloc_section;
792 ret->dt_reloc = DT_REL;
793 ret->dt_reloc_sz = DT_RELSZ;
794 ret->dt_reloc_ent = DT_RELENT;
503294e7 795 ret->sizeof_reloc = sizeof (Elf32_External_Rel);
9ff114ca 796 ret->got_entry_size = 4;
765e526c
L
797 ret->pointer_r_type = R_386_32;
798 ret->dynamic_interpreter = ELF32_DYNAMIC_INTERPRETER;
799 ret->dynamic_interpreter_size
800 = sizeof ELF32_DYNAMIC_INTERPRETER;
801 ret->tls_get_addr = "___tls_get_addr";
802 }
803 }
fe53b4a4 804 ret->target_id = bed->target_id;
765e526c
L
805
806 ret->loc_hash_table = htab_try_create (1024,
807 _bfd_x86_elf_local_htab_hash,
808 _bfd_x86_elf_local_htab_eq,
809 NULL);
810 ret->loc_hash_memory = objalloc_create ();
811 if (!ret->loc_hash_table || !ret->loc_hash_memory)
812 {
813 elf_x86_link_hash_table_free (abfd);
814 return NULL;
815 }
816 ret->elf.root.hash_table_free = elf_x86_link_hash_table_free;
817
818 return &ret->elf.root;
819}
820
0afcef53
L
821/* Sort relocs into address order. */
822
823int
824_bfd_x86_elf_compare_relocs (const void *ap, const void *bp)
825{
826 const arelent *a = * (const arelent **) ap;
827 const arelent *b = * (const arelent **) bp;
828
829 if (a->address > b->address)
830 return 1;
831 else if (a->address < b->address)
832 return -1;
833 else
834 return 0;
835}
836
837bfd_boolean
838_bfd_x86_elf_link_check_relocs (bfd *abfd, struct bfd_link_info *info)
839{
840 if (!bfd_link_relocatable (info))
841 {
842 /* Check for __tls_get_addr reference. */
843 struct elf_x86_link_hash_table *htab;
844 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
845 htab = elf_x86_hash_table (info, bed->target_id);
846 if (htab)
847 {
0a27fed7
L
848 struct elf_link_hash_entry *h;
849
850 h = elf_link_hash_lookup (elf_hash_table (info),
0afcef53
L
851 htab->tls_get_addr,
852 FALSE, FALSE, FALSE);
853 if (h != NULL)
0a27fed7
L
854 elf_x86_hash_entry (h)->tls_get_addr = 1;
855
856 /* "__ehdr_start" will be defined by linker as a hidden symbol
857 later if it is referenced and not defined. */
858 h = elf_link_hash_lookup (elf_hash_table (info),
859 "__ehdr_start",
860 FALSE, FALSE, FALSE);
861 if (h != NULL
862 && (h->root.type == bfd_link_hash_new
863 || h->root.type == bfd_link_hash_undefined
864 || h->root.type == bfd_link_hash_undefweak
865 || h->root.type == bfd_link_hash_common))
866 {
867 elf_x86_hash_entry (h)->local_ref = 2;
868 elf_x86_hash_entry (h)->linker_def = 1;
869 }
0afcef53
L
870 }
871 }
872
873 /* Invoke the regular ELF backend linker to do all the work. */
874 return _bfd_elf_link_check_relocs (abfd, info);
875}
876
5e2ac45d
L
877/* Set the sizes of the dynamic sections. */
878
879bfd_boolean
880_bfd_x86_elf_size_dynamic_sections (bfd *output_bfd,
881 struct bfd_link_info *info)
882{
883 struct elf_x86_link_hash_table *htab;
884 bfd *dynobj;
885 asection *s;
886 bfd_boolean relocs;
887 bfd *ibfd;
888 const struct elf_backend_data *bed
889 = get_elf_backend_data (output_bfd);
890
891 htab = elf_x86_hash_table (info, bed->target_id);
892 if (htab == NULL)
893 return FALSE;
894 dynobj = htab->elf.dynobj;
895 if (dynobj == NULL)
896 abort ();
897
898 /* Set up .got offsets for local syms, and space for local dynamic
899 relocs. */
900 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
901 {
902 bfd_signed_vma *local_got;
903 bfd_signed_vma *end_local_got;
904 char *local_tls_type;
905 bfd_vma *local_tlsdesc_gotent;
906 bfd_size_type locsymcount;
907 Elf_Internal_Shdr *symtab_hdr;
908 asection *srel;
909
910 if (! is_x86_elf (ibfd, htab))
911 continue;
912
913 for (s = ibfd->sections; s != NULL; s = s->next)
914 {
915 struct elf_dyn_relocs *p;
916
5e2ac45d
L
917 for (p = ((struct elf_dyn_relocs *)
918 elf_section_data (s)->local_dynrel);
919 p != NULL;
920 p = p->next)
921 {
922 if (!bfd_is_abs_section (p->sec)
923 && bfd_is_abs_section (p->sec->output_section))
924 {
925 /* Input section has been discarded, either because
926 it is a copy of a linkonce section or due to
927 linker script /DISCARD/, so we'll be discarding
928 the relocs too. */
929 }
930 else if (htab->is_vxworks
931 && strcmp (p->sec->output_section->name,
932 ".tls_vars") == 0)
933 {
934 /* Relocations in vxworks .tls_vars sections are
935 handled specially by the loader. */
936 }
937 else if (p->count != 0)
938 {
939 srel = elf_section_data (p->sec)->sreloc;
940 srel->size += p->count * htab->sizeof_reloc;
941 if ((p->sec->output_section->flags & SEC_READONLY) != 0
942 && (info->flags & DF_TEXTREL) == 0)
943 {
944 info->flags |= DF_TEXTREL;
945 if ((info->warn_shared_textrel && bfd_link_pic (info))
946 || info->error_textrel)
947 /* xgettext:c-format */
948 info->callbacks->einfo (_("%P: %B: warning: relocation in readonly section `%A'\n"),
949 p->sec->owner, p->sec);
950 }
951 }
952 }
953 }
954
955 local_got = elf_local_got_refcounts (ibfd);
956 if (!local_got)
957 continue;
958
959 symtab_hdr = &elf_symtab_hdr (ibfd);
960 locsymcount = symtab_hdr->sh_info;
961 end_local_got = local_got + locsymcount;
962 local_tls_type = elf_x86_local_got_tls_type (ibfd);
963 local_tlsdesc_gotent = elf_x86_local_tlsdesc_gotent (ibfd);
964 s = htab->elf.sgot;
965 srel = htab->elf.srelgot;
966 for (; local_got < end_local_got;
967 ++local_got, ++local_tls_type, ++local_tlsdesc_gotent)
968 {
969 *local_tlsdesc_gotent = (bfd_vma) -1;
970 if (*local_got > 0)
971 {
972 if (GOT_TLS_GDESC_P (*local_tls_type))
973 {
974 *local_tlsdesc_gotent = htab->elf.sgotplt->size
975 - elf_x86_compute_jump_table_size (htab);
976 htab->elf.sgotplt->size += 2 * htab->got_entry_size;
977 *local_got = (bfd_vma) -2;
978 }
979 if (! GOT_TLS_GDESC_P (*local_tls_type)
980 || GOT_TLS_GD_P (*local_tls_type))
981 {
982 *local_got = s->size;
983 s->size += htab->got_entry_size;
984 if (GOT_TLS_GD_P (*local_tls_type)
985 || *local_tls_type == GOT_TLS_IE_BOTH)
986 s->size += htab->got_entry_size;
987 }
988 if (bfd_link_pic (info)
989 || GOT_TLS_GD_ANY_P (*local_tls_type)
990 || (*local_tls_type & GOT_TLS_IE))
991 {
992 if (*local_tls_type == GOT_TLS_IE_BOTH)
993 srel->size += 2 * htab->sizeof_reloc;
994 else if (GOT_TLS_GD_P (*local_tls_type)
995 || ! GOT_TLS_GDESC_P (*local_tls_type))
996 srel->size += htab->sizeof_reloc;
997 if (GOT_TLS_GDESC_P (*local_tls_type))
998 {
999 htab->elf.srelplt->size += htab->sizeof_reloc;
1000 if (bed->target_id == X86_64_ELF_DATA)
1001 htab->tlsdesc_plt = (bfd_vma) -1;
1002 }
1003 }
1004 }
1005 else
1006 *local_got = (bfd_vma) -1;
1007 }
1008 }
1009
1010 if (htab->tls_ld_or_ldm_got.refcount > 0)
1011 {
1012 /* Allocate 2 got entries and 1 dynamic reloc for R_386_TLS_LDM
1013 or R_X86_64_TLSLD relocs. */
1014 htab->tls_ld_or_ldm_got.offset = htab->elf.sgot->size;
1015 htab->elf.sgot->size += 2 * htab->got_entry_size;
1016 htab->elf.srelgot->size += htab->sizeof_reloc;
1017 }
1018 else
1019 htab->tls_ld_or_ldm_got.offset = -1;
1020
1021 /* Allocate global sym .plt and .got entries, and space for global
1022 sym dynamic relocs. */
1023 elf_link_hash_traverse (&htab->elf, elf_x86_allocate_dynrelocs,
1024 info);
1025
1026 /* Allocate .plt and .got entries, and space for local symbols. */
1027 htab_traverse (htab->loc_hash_table, elf_x86_allocate_local_dynreloc,
1028 info);
1029
1030 /* For every jump slot reserved in the sgotplt, reloc_count is
1031 incremented. However, when we reserve space for TLS descriptors,
1032 it's not incremented, so in order to compute the space reserved
1033 for them, it suffices to multiply the reloc count by the jump
1034 slot size.
1035
1036 PR ld/13302: We start next_irelative_index at the end of .rela.plt
1037 so that R_{386,X86_64}_IRELATIVE entries come last. */
1038 if (htab->elf.srelplt)
1039 {
1040 htab->next_tls_desc_index = htab->elf.srelplt->reloc_count;
1041 htab->sgotplt_jump_table_size
1042 = elf_x86_compute_jump_table_size (htab);
1043 htab->next_irelative_index = htab->elf.srelplt->reloc_count - 1;
1044 }
1045 else if (htab->elf.irelplt)
1046 htab->next_irelative_index = htab->elf.irelplt->reloc_count - 1;
1047
1048 if (htab->tlsdesc_plt)
1049 {
1050 /* NB: tlsdesc_plt is set only for x86-64. If we're not using
1051 lazy TLS relocations, don't generate the PLT and GOT entries
1052 they require. */
1053 if ((info->flags & DF_BIND_NOW))
1054 htab->tlsdesc_plt = 0;
1055 else
1056 {
1057 htab->tlsdesc_got = htab->elf.sgot->size;
1058 htab->elf.sgot->size += htab->got_entry_size;
1059 /* Reserve room for the initial entry.
1060 FIXME: we could probably do away with it in this case. */
1061 if (htab->elf.splt->size == 0)
1062 htab->elf.splt->size = htab->plt.plt_entry_size;
1063 htab->tlsdesc_plt = htab->elf.splt->size;
1064 htab->elf.splt->size += htab->plt.plt_entry_size;
1065 }
1066 }
1067
1068 if (htab->elf.sgotplt)
1069 {
1070 /* Don't allocate .got.plt section if there are no GOT nor PLT
1071 entries and there is no reference to _GLOBAL_OFFSET_TABLE_. */
1072 if ((htab->elf.hgot == NULL
1073 || !htab->elf.hgot->ref_regular_nonweak)
1074 && (htab->elf.sgotplt->size == bed->got_header_size)
1075 && (htab->elf.splt == NULL
1076 || htab->elf.splt->size == 0)
1077 && (htab->elf.sgot == NULL
1078 || htab->elf.sgot->size == 0)
1079 && (htab->elf.iplt == NULL
1080 || htab->elf.iplt->size == 0)
1081 && (htab->elf.igotplt == NULL
1082 || htab->elf.igotplt->size == 0))
1083 htab->elf.sgotplt->size = 0;
1084 }
1085
1086 if (_bfd_elf_eh_frame_present (info))
1087 {
1088 if (htab->plt_eh_frame != NULL
1089 && htab->elf.splt != NULL
1090 && htab->elf.splt->size != 0
1091 && !bfd_is_abs_section (htab->elf.splt->output_section))
1092 htab->plt_eh_frame->size = htab->plt.eh_frame_plt_size;
1093
1094 if (htab->plt_got_eh_frame != NULL
1095 && htab->plt_got != NULL
1096 && htab->plt_got->size != 0
1097 && !bfd_is_abs_section (htab->plt_got->output_section))
1098 htab->plt_got_eh_frame->size
1099 = htab->non_lazy_plt->eh_frame_plt_size;
1100
1101 /* Unwind info for the second PLT and .plt.got sections are
1102 identical. */
1103 if (htab->plt_second_eh_frame != NULL
1104 && htab->plt_second != NULL
1105 && htab->plt_second->size != 0
1106 && !bfd_is_abs_section (htab->plt_second->output_section))
1107 htab->plt_second_eh_frame->size
1108 = htab->non_lazy_plt->eh_frame_plt_size;
1109 }
1110
1111 /* We now have determined the sizes of the various dynamic sections.
1112 Allocate memory for them. */
1113 relocs = FALSE;
1114 for (s = dynobj->sections; s != NULL; s = s->next)
1115 {
1116 bfd_boolean strip_section = TRUE;
1117
1118 if ((s->flags & SEC_LINKER_CREATED) == 0)
1119 continue;
1120
1121 if (s == htab->elf.splt
1122 || s == htab->elf.sgot)
1123 {
1124 /* Strip this section if we don't need it; see the
1125 comment below. */
1126 /* We'd like to strip these sections if they aren't needed, but if
1127 we've exported dynamic symbols from them we must leave them.
1128 It's too late to tell BFD to get rid of the symbols. */
1129
1130 if (htab->elf.hplt != NULL)
1131 strip_section = FALSE;
1132 }
1133 else if (s == htab->elf.sgotplt
1134 || s == htab->elf.iplt
1135 || s == htab->elf.igotplt
1136 || s == htab->plt_second
1137 || s == htab->plt_got
1138 || s == htab->plt_eh_frame
1139 || s == htab->plt_got_eh_frame
1140 || s == htab->plt_second_eh_frame
1141 || s == htab->elf.sdynbss
1142 || s == htab->elf.sdynrelro)
1143 {
1144 /* Strip these too. */
1145 }
1146 else if (htab->is_reloc_section (bfd_get_section_name (dynobj, s)))
1147 {
1148 if (s->size != 0
1149 && s != htab->elf.srelplt
1150 && s != htab->srelplt2)
1151 relocs = TRUE;
1152
1153 /* We use the reloc_count field as a counter if we need
1154 to copy relocs into the output file. */
1155 if (s != htab->elf.srelplt)
1156 s->reloc_count = 0;
1157 }
1158 else
1159 {
1160 /* It's not one of our sections, so don't allocate space. */
1161 continue;
1162 }
1163
1164 if (s->size == 0)
1165 {
1166 /* If we don't need this section, strip it from the
1167 output file. This is mostly to handle .rel.bss and
1168 .rel.plt. We must create both sections in
1169 create_dynamic_sections, because they must be created
1170 before the linker maps input sections to output
1171 sections. The linker does that before
1172 adjust_dynamic_symbol is called, and it is that
1173 function which decides whether anything needs to go
1174 into these sections. */
1175 if (strip_section)
1176 s->flags |= SEC_EXCLUDE;
1177 continue;
1178 }
1179
1180 if ((s->flags & SEC_HAS_CONTENTS) == 0)
1181 continue;
1182
1183 /* Allocate memory for the section contents. We use bfd_zalloc
1184 here in case unused entries are not reclaimed before the
1185 section's contents are written out. This should not happen,
1186 but this way if it does, we get a R_386_NONE or R_X86_64_NONE
1187 reloc instead of garbage. */
1188 s->contents = (unsigned char *) bfd_zalloc (dynobj, s->size);
1189 if (s->contents == NULL)
1190 return FALSE;
1191 }
1192
1193 if (htab->plt_eh_frame != NULL
1194 && htab->plt_eh_frame->contents != NULL)
1195 {
1196 memcpy (htab->plt_eh_frame->contents,
1197 htab->plt.eh_frame_plt,
1198 htab->plt_eh_frame->size);
1199 bfd_put_32 (dynobj, htab->elf.splt->size,
1200 htab->plt_eh_frame->contents + PLT_FDE_LEN_OFFSET);
1201 }
1202
1203 if (htab->plt_got_eh_frame != NULL
1204 && htab->plt_got_eh_frame->contents != NULL)
1205 {
1206 memcpy (htab->plt_got_eh_frame->contents,
1207 htab->non_lazy_plt->eh_frame_plt,
1208 htab->plt_got_eh_frame->size);
1209 bfd_put_32 (dynobj, htab->plt_got->size,
1210 (htab->plt_got_eh_frame->contents
1211 + PLT_FDE_LEN_OFFSET));
1212 }
1213
1214 if (htab->plt_second_eh_frame != NULL
1215 && htab->plt_second_eh_frame->contents != NULL)
1216 {
1217 memcpy (htab->plt_second_eh_frame->contents,
1218 htab->non_lazy_plt->eh_frame_plt,
1219 htab->plt_second_eh_frame->size);
1220 bfd_put_32 (dynobj, htab->plt_second->size,
1221 (htab->plt_second_eh_frame->contents
1222 + PLT_FDE_LEN_OFFSET));
1223 }
1224
1225 if (htab->elf.dynamic_sections_created)
1226 {
1227 /* Add some entries to the .dynamic section. We fill in the
1228 values later, in elf_{i386,x86_64}_finish_dynamic_sections,
1229 but we must add the entries now so that we get the correct
1230 size for the .dynamic section. The DT_DEBUG entry is filled
1231 in by the dynamic linker and used by the debugger. */
1232#define add_dynamic_entry(TAG, VAL) \
1233 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
1234
1235 if (bfd_link_executable (info))
1236 {
1237 if (!add_dynamic_entry (DT_DEBUG, 0))
1238 return FALSE;
1239 }
1240
1241 if (htab->elf.splt->size != 0)
1242 {
1243 /* DT_PLTGOT is used by prelink even if there is no PLT
1244 relocation. */
1245 if (!add_dynamic_entry (DT_PLTGOT, 0))
1246 return FALSE;
1247 }
1248
1249 if (htab->elf.srelplt->size != 0)
1250 {
1251 if (!add_dynamic_entry (DT_PLTRELSZ, 0)
1252 || !add_dynamic_entry (DT_PLTREL, htab->dt_reloc)
1253 || !add_dynamic_entry (DT_JMPREL, 0))
1254 return FALSE;
1255 }
1256
1257 if (htab->tlsdesc_plt
1258 && (!add_dynamic_entry (DT_TLSDESC_PLT, 0)
1259 || !add_dynamic_entry (DT_TLSDESC_GOT, 0)))
1260 return FALSE;
1261
1262 if (relocs)
1263 {
1264 if (!add_dynamic_entry (htab->dt_reloc, 0)
1265 || !add_dynamic_entry (htab->dt_reloc_sz, 0)
1266 || !add_dynamic_entry (htab->dt_reloc_ent,
1267 htab->sizeof_reloc))
1268 return FALSE;
1269
1270 /* If any dynamic relocs apply to a read-only section,
1271 then we need a DT_TEXTREL entry. */
1272 if ((info->flags & DF_TEXTREL) == 0)
1273 elf_link_hash_traverse (&htab->elf,
1274 _bfd_x86_elf_readonly_dynrelocs,
1275 info);
1276
1277 if ((info->flags & DF_TEXTREL) != 0)
1278 {
1279 if (htab->readonly_dynrelocs_against_ifunc)
1280 {
1281 info->callbacks->einfo
1282 (_("%P%X: read-only segment has dynamic IFUNC relocations; recompile with -fPIC\n"));
1283 bfd_set_error (bfd_error_bad_value);
1284 return FALSE;
1285 }
1286
1287 if (!add_dynamic_entry (DT_TEXTREL, 0))
1288 return FALSE;
1289 }
1290 }
1291 if (htab->is_vxworks
1292 && !elf_vxworks_add_dynamic_entries (output_bfd, info))
1293 return FALSE;
1294 }
1295#undef add_dynamic_entry
1296
1297 return TRUE;
1298}
1299
0afcef53
L
1300bfd_boolean
1301_bfd_x86_elf_always_size_sections (bfd *output_bfd,
1302 struct bfd_link_info *info)
1303{
1304 asection *tls_sec = elf_hash_table (info)->tls_sec;
1305
1306 if (tls_sec)
1307 {
1308 struct elf_link_hash_entry *tlsbase;
1309
1310 tlsbase = elf_link_hash_lookup (elf_hash_table (info),
1311 "_TLS_MODULE_BASE_",
1312 FALSE, FALSE, FALSE);
1313
1314 if (tlsbase && tlsbase->type == STT_TLS)
1315 {
1316 struct elf_x86_link_hash_table *htab;
1317 struct bfd_link_hash_entry *bh = NULL;
1318 const struct elf_backend_data *bed
1319 = get_elf_backend_data (output_bfd);
1320
1321 htab = elf_x86_hash_table (info, bed->target_id);
1322 if (htab == NULL)
1323 return FALSE;
1324
1325 if (!(_bfd_generic_link_add_one_symbol
1326 (info, output_bfd, "_TLS_MODULE_BASE_", BSF_LOCAL,
1327 tls_sec, 0, NULL, FALSE,
1328 bed->collect, &bh)))
1329 return FALSE;
1330
1331 htab->tls_module_base = bh;
1332
1333 tlsbase = (struct elf_link_hash_entry *)bh;
1334 tlsbase->def_regular = 1;
1335 tlsbase->other = STV_HIDDEN;
1336 tlsbase->root.linker_def = 1;
1337 (*bed->elf_backend_hide_symbol) (info, tlsbase, TRUE);
1338 }
1339 }
1340
1341 return TRUE;
1342}
1343
1344void
1345_bfd_x86_elf_merge_symbol_attribute (struct elf_link_hash_entry *h,
1346 const Elf_Internal_Sym *isym,
1347 bfd_boolean definition,
1348 bfd_boolean dynamic ATTRIBUTE_UNUSED)
1349{
1350 if (definition)
1351 {
1352 struct elf_x86_link_hash_entry *eh
1353 = (struct elf_x86_link_hash_entry *) h;
1354 eh->def_protected = (ELF_ST_VISIBILITY (isym->st_other)
1355 == STV_PROTECTED);
1356 }
1357}
1358
1359/* Copy the extra info we tack onto an elf_link_hash_entry. */
1360
1361void
1362_bfd_x86_elf_copy_indirect_symbol (struct bfd_link_info *info,
1363 struct elf_link_hash_entry *dir,
1364 struct elf_link_hash_entry *ind)
1365{
1366 struct elf_x86_link_hash_entry *edir, *eind;
1367
1368 edir = (struct elf_x86_link_hash_entry *) dir;
1369 eind = (struct elf_x86_link_hash_entry *) ind;
1370
1371 if (eind->dyn_relocs != NULL)
1372 {
1373 if (edir->dyn_relocs != NULL)
1374 {
1375 struct elf_dyn_relocs **pp;
1376 struct elf_dyn_relocs *p;
1377
1378 /* Add reloc counts against the indirect sym to the direct sym
1379 list. Merge any entries against the same section. */
1380 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
1381 {
1382 struct elf_dyn_relocs *q;
1383
1384 for (q = edir->dyn_relocs; q != NULL; q = q->next)
1385 if (q->sec == p->sec)
1386 {
1387 q->pc_count += p->pc_count;
1388 q->count += p->count;
1389 *pp = p->next;
1390 break;
1391 }
1392 if (q == NULL)
1393 pp = &p->next;
1394 }
1395 *pp = edir->dyn_relocs;
1396 }
1397
1398 edir->dyn_relocs = eind->dyn_relocs;
1399 eind->dyn_relocs = NULL;
1400 }
1401
1402 if (ind->root.type == bfd_link_hash_indirect
1403 && dir->got.refcount <= 0)
1404 {
1405 edir->tls_type = eind->tls_type;
1406 eind->tls_type = GOT_UNKNOWN;
1407 }
1408
1409 /* Copy gotoff_ref so that elf_i386_adjust_dynamic_symbol will
1410 generate a R_386_COPY reloc. */
1411 edir->gotoff_ref |= eind->gotoff_ref;
1412
1413 edir->has_got_reloc |= eind->has_got_reloc;
1414 edir->has_non_got_reloc |= eind->has_non_got_reloc;
1415
1416 if (ELIMINATE_COPY_RELOCS
1417 && ind->root.type != bfd_link_hash_indirect
1418 && dir->dynamic_adjusted)
1419 {
1420 /* If called to transfer flags for a weakdef during processing
1421 of elf_adjust_dynamic_symbol, don't copy non_got_ref.
1422 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
1423 if (dir->versioned != versioned_hidden)
1424 dir->ref_dynamic |= ind->ref_dynamic;
1425 dir->ref_regular |= ind->ref_regular;
1426 dir->ref_regular_nonweak |= ind->ref_regular_nonweak;
1427 dir->needs_plt |= ind->needs_plt;
1428 dir->pointer_equality_needed |= ind->pointer_equality_needed;
1429 }
1430 else
1431 {
1432 if (eind->func_pointer_refcount > 0)
1433 {
1434 edir->func_pointer_refcount += eind->func_pointer_refcount;
1435 eind->func_pointer_refcount = 0;
1436 }
1437
1438 _bfd_elf_link_hash_copy_indirect (info, dir, ind);
1439 }
1440}
1441
1442/* Remove undefined weak symbol from the dynamic symbol table if it
1443 is resolved to 0. */
1444
1445bfd_boolean
1446_bfd_x86_elf_fixup_symbol (struct bfd_link_info *info,
1447 struct elf_link_hash_entry *h)
1448{
1449 if (h->dynindx != -1)
1450 {
1451 const struct elf_backend_data *bed
1452 = get_elf_backend_data (info->output_bfd);
1453 if (UNDEFINED_WEAK_RESOLVED_TO_ZERO (info,
1454 bed->target_id,
1455 elf_x86_hash_entry (h)->has_got_reloc,
1456 elf_x86_hash_entry (h)))
1457 {
1458 h->dynindx = -1;
1459 _bfd_elf_strtab_delref (elf_hash_table (info)->dynstr,
1460 h->dynstr_index);
1461 }
1462 }
1463 return TRUE;
1464}
1465
1466/* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */
1467
1468bfd_boolean
1469_bfd_x86_elf_hash_symbol (struct elf_link_hash_entry *h)
1470{
1471 if (h->plt.offset != (bfd_vma) -1
1472 && !h->def_regular
1473 && !h->pointer_equality_needed)
1474 return FALSE;
1475
1476 return _bfd_elf_hash_symbol (h);
1477}
1478
eeb2f20a
L
1479/* Adjust a symbol defined by a dynamic object and referenced by a
1480 regular object. The current definition is in some section of the
1481 dynamic object, but we're not including those sections. We have to
1482 change the definition to something the rest of the link can
1483 understand. */
1484
1485bfd_boolean
1486_bfd_x86_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
1487 struct elf_link_hash_entry *h)
1488{
1489 struct elf_x86_link_hash_table *htab;
1490 asection *s, *srel;
1491 struct elf_x86_link_hash_entry *eh;
1492 struct elf_dyn_relocs *p;
1493 const struct elf_backend_data *bed
1494 = get_elf_backend_data (info->output_bfd);
1495
1496 /* STT_GNU_IFUNC symbol must go through PLT. */
1497 if (h->type == STT_GNU_IFUNC)
1498 {
1499 /* All local STT_GNU_IFUNC references must be treate as local
1500 calls via local PLT. */
1501 if (h->ref_regular
1502 && SYMBOL_CALLS_LOCAL (info, h))
1503 {
1504 bfd_size_type pc_count = 0, count = 0;
1505 struct elf_dyn_relocs **pp;
1506
1507 eh = (struct elf_x86_link_hash_entry *) h;
1508 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1509 {
1510 pc_count += p->pc_count;
1511 p->count -= p->pc_count;
1512 p->pc_count = 0;
1513 count += p->count;
1514 if (p->count == 0)
1515 *pp = p->next;
1516 else
1517 pp = &p->next;
1518 }
1519
1520 if (pc_count || count)
1521 {
1522 h->non_got_ref = 1;
1523 if (pc_count)
1524 {
1525 /* Increment PLT reference count only for PC-relative
1526 references. */
1527 h->needs_plt = 1;
1528 if (h->plt.refcount <= 0)
1529 h->plt.refcount = 1;
1530 else
1531 h->plt.refcount += 1;
1532 }
1533 }
1534 }
1535
1536 if (h->plt.refcount <= 0)
1537 {
1538 h->plt.offset = (bfd_vma) -1;
1539 h->needs_plt = 0;
1540 }
1541 return TRUE;
1542 }
1543
1544 /* If this is a function, put it in the procedure linkage table. We
1545 will fill in the contents of the procedure linkage table later,
1546 when we know the address of the .got section. */
1547 if (h->type == STT_FUNC
1548 || h->needs_plt)
1549 {
1550 if (h->plt.refcount <= 0
1551 || SYMBOL_CALLS_LOCAL (info, h)
1552 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1553 && h->root.type == bfd_link_hash_undefweak))
1554 {
1555 /* This case can occur if we saw a PLT32 reloc in an input
1556 file, but the symbol was never referred to by a dynamic
1557 object, or if all references were garbage collected. In
1558 such a case, we don't actually need to build a procedure
1559 linkage table, and we can just do a PC32 reloc instead. */
1560 h->plt.offset = (bfd_vma) -1;
1561 h->needs_plt = 0;
1562 }
1563
1564 return TRUE;
1565 }
1566 else
1567 /* It's possible that we incorrectly decided a .plt reloc was needed
1568 * for an R_386_PC32/R_X86_64_PC32 reloc to a non-function sym in
1569 check_relocs. We can't decide accurately between function and
1570 non-function syms in check-relocs; Objects loaded later in
1571 the link may change h->type. So fix it now. */
1572 h->plt.offset = (bfd_vma) -1;
1573
1574 eh = (struct elf_x86_link_hash_entry *) h;
1575
1576 /* If this is a weak symbol, and there is a real definition, the
1577 processor independent code will have arranged for us to see the
1578 real definition first, and we can just use the same value. */
1579 if (h->u.weakdef != NULL)
1580 {
1581 BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined
1582 || h->u.weakdef->root.type == bfd_link_hash_defweak);
1583 h->root.u.def.section = h->u.weakdef->root.u.def.section;
1584 h->root.u.def.value = h->u.weakdef->root.u.def.value;
1585 if (ELIMINATE_COPY_RELOCS
1586 || info->nocopyreloc
1587 || SYMBOL_NO_COPYRELOC (info, eh))
1588 {
1589 /* NB: needs_copy is always 0 for i386. */
1590 h->non_got_ref = h->u.weakdef->non_got_ref;
1591 eh->needs_copy = h->u.weakdef->needs_copy;
1592 }
1593 return TRUE;
1594 }
1595
1596 /* This is a reference to a symbol defined by a dynamic object which
1597 is not a function. */
1598
1599 /* If we are creating a shared library, we must presume that the
1600 only references to the symbol are via the global offset table.
1601 For such cases we need not do anything here; the relocations will
1602 be handled correctly by relocate_section. */
1603 if (!bfd_link_executable (info))
1604 return TRUE;
1605
1606 /* If there are no references to this symbol that do not use the
1607 GOT nor R_386_GOTOFF relocation, we don't need to generate a copy
1608 reloc. NB: gotoff_ref is always 0 for x86-64. */
1609 if (!h->non_got_ref && !eh->gotoff_ref)
1610 return TRUE;
1611
1612 /* If -z nocopyreloc was given, we won't generate them either. */
1613 if (info->nocopyreloc || SYMBOL_NO_COPYRELOC (info, eh))
1614 {
1615 h->non_got_ref = 0;
1616 return TRUE;
1617 }
1618
1619 htab = elf_x86_hash_table (info, bed->target_id);
1620 if (htab == NULL)
1621 return FALSE;
1622
1623 /* If there aren't any dynamic relocs in read-only sections nor
1624 R_386_GOTOFF relocation, then we can keep the dynamic relocs and
1625 avoid the copy reloc. This doesn't work on VxWorks, where we can
1626 not have dynamic relocations (other than copy and jump slot
1627 relocations) in an executable. */
1628 if (ELIMINATE_COPY_RELOCS
1629 && (bed->target_id == X86_64_ELF_DATA
1630 || (!eh->gotoff_ref
1631 && !htab->is_vxworks)))
1632 {
1633 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1634 {
1635 s = p->sec->output_section;
1636 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1637 break;
1638 }
1639
1640 /* If we didn't find any dynamic relocs in read-only sections,
1641 then we'll be keeping the dynamic relocs and avoiding the copy
1642 reloc. */
1643 if (p == NULL)
1644 {
1645 h->non_got_ref = 0;
1646 return TRUE;
1647 }
1648 }
1649
1650 /* We must allocate the symbol in our .dynbss section, which will
1651 become part of the .bss section of the executable. There will be
1652 an entry for this symbol in the .dynsym section. The dynamic
1653 object will contain position independent code, so all references
1654 from the dynamic object to this symbol will go through the global
1655 offset table. The dynamic linker will use the .dynsym entry to
1656 determine the address it must put in the global offset table, so
1657 both the dynamic object and the regular object will refer to the
1658 same memory location for the variable. */
1659
1660 /* We must generate a R_386_COPY/R_X86_64_COPY reloc to tell the
1661 dynamic linker to copy the initial value out of the dynamic object
1662 and into the runtime process image. */
1663 if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
1664 {
1665 s = htab->elf.sdynrelro;
1666 srel = htab->elf.sreldynrelro;
1667 }
1668 else
1669 {
1670 s = htab->elf.sdynbss;
1671 srel = htab->elf.srelbss;
1672 }
1673 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
1674 {
503294e7 1675 srel->size += htab->sizeof_reloc;
eeb2f20a
L
1676 h->needs_copy = 1;
1677 }
1678
1679 return _bfd_elf_adjust_dynamic_copy (info, h, s);
1680}
1681
6999821f
L
1682/* Return TRUE if a symbol is referenced locally. It is similar to
1683 SYMBOL_REFERENCES_LOCAL, but it also checks version script. It
1684 works in check_relocs. */
1685
1686bfd_boolean
1687_bfd_x86_elf_link_symbol_references_local (struct bfd_link_info *info,
1688 struct elf_link_hash_entry *h)
1689{
0a27fed7
L
1690 struct elf_x86_link_hash_entry *eh = elf_x86_hash_entry (h);
1691 struct elf_x86_link_hash_table *htab
1692 = (struct elf_x86_link_hash_table *) info->hash;
6999821f
L
1693
1694 if (eh->local_ref > 1)
1695 return TRUE;
1696
1697 if (eh->local_ref == 1)
1698 return FALSE;
1699
1700 /* Unversioned symbols defined in regular objects can be forced local
0a27fed7
L
1701 by linker version script. A weak undefined symbol is forced local
1702 if
1703 1. It has non-default visibility. Or
1704 2. When building executable, it has non-GOT/non-PLT relocations
1705 in text section or there is no dynamic linker. Or
1706 3. or "-z nodynamic-undefined-weak" is used.
1707 */
6999821f 1708 if (SYMBOL_REFERENCES_LOCAL (info, h)
0a27fed7
L
1709 || (h->root.type == bfd_link_hash_undefweak
1710 && (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1711 || (bfd_link_executable (info)
1712 && (htab->interp == NULL || eh->has_non_got_reloc))
1713 || info->dynamic_undefined_weak == 0))
6999821f
L
1714 || ((h->def_regular || ELF_COMMON_DEF_P (h))
1715 && h->versioned == unversioned
1716 && info->version_info != NULL
1717 && bfd_hide_sym_by_version (info->version_info,
1718 h->root.root.string)))
1719 {
1720 eh->local_ref = 2;
1721 return TRUE;
1722 }
1723
1724 eh->local_ref = 1;
1725 return FALSE;
1726}
1727
4f501a24
L
1728/* Return the section that should be marked against GC for a given
1729 relocation. */
1730
1731asection *
1732_bfd_x86_elf_gc_mark_hook (asection *sec,
1733 struct bfd_link_info *info,
1734 Elf_Internal_Rela *rel,
1735 struct elf_link_hash_entry *h,
1736 Elf_Internal_Sym *sym)
1737{
1738 /* Compiler should optimize this out. */
1739 if (((unsigned int) R_X86_64_GNU_VTINHERIT
1740 != (unsigned int) R_386_GNU_VTINHERIT)
1741 || ((unsigned int) R_X86_64_GNU_VTENTRY
1742 != (unsigned int) R_386_GNU_VTENTRY))
1743 abort ();
1744
1745 if (h != NULL)
1746 switch (ELF32_R_TYPE (rel->r_info))
1747 {
1748 case R_X86_64_GNU_VTINHERIT:
1749 case R_X86_64_GNU_VTENTRY:
1750 return NULL;
1751 }
1752
1753 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
1754}
1755
f493882d
L
1756static bfd_vma
1757elf_i386_get_plt_got_vma (struct elf_x86_plt *plt_p ATTRIBUTE_UNUSED,
1758 bfd_vma off,
1759 bfd_vma offset ATTRIBUTE_UNUSED,
1760 bfd_vma got_addr)
1761{
1762 return got_addr + off;
1763}
1764
1765static bfd_vma
1766elf_x86_64_get_plt_got_vma (struct elf_x86_plt *plt_p,
1767 bfd_vma off,
1768 bfd_vma offset,
1769 bfd_vma got_addr ATTRIBUTE_UNUSED)
1770{
1771 return plt_p->sec->vma + offset + off + plt_p->plt_got_insn_size;
1772}
1773
1774static bfd_boolean
1775elf_i386_valid_plt_reloc_p (unsigned int type)
1776{
1777 return (type == R_386_JUMP_SLOT
1778 || type == R_386_GLOB_DAT
1779 || type == R_386_IRELATIVE);
1780}
1781
1782static bfd_boolean
1783elf_x86_64_valid_plt_reloc_p (unsigned int type)
1784{
1785 return (type == R_X86_64_JUMP_SLOT
1786 || type == R_X86_64_GLOB_DAT
1787 || type == R_X86_64_IRELATIVE);
1788}
1789
1790long
1791_bfd_x86_elf_get_synthetic_symtab (bfd *abfd,
1792 long count,
1793 long relsize,
1794 bfd_vma got_addr,
1795 struct elf_x86_plt plts[],
1796 asymbol **dynsyms,
1797 asymbol **ret)
1798{
1799 long size, i, n, len;
1800 int j;
1801 unsigned int plt_got_offset, plt_entry_size;
1802 asymbol *s;
1803 bfd_byte *plt_contents;
1804 long dynrelcount;
1805 arelent **dynrelbuf, *p;
1806 char *names;
1807 const struct elf_backend_data *bed;
1808 bfd_vma (*get_plt_got_vma) (struct elf_x86_plt *, bfd_vma, bfd_vma,
1809 bfd_vma);
1810 bfd_boolean (*valid_plt_reloc_p) (unsigned int);
1811
1812 if (count == 0)
1813 return -1;
1814
1815 dynrelbuf = (arelent **) bfd_malloc (relsize);
1816 if (dynrelbuf == NULL)
1817 return -1;
1818
1819 dynrelcount = bfd_canonicalize_dynamic_reloc (abfd, dynrelbuf,
1820 dynsyms);
1821
1822 /* Sort the relocs by address. */
1823 qsort (dynrelbuf, dynrelcount, sizeof (arelent *),
1824 _bfd_x86_elf_compare_relocs);
1825
1826 size = count * sizeof (asymbol);
1827
1828 /* Allocate space for @plt suffixes. */
1829 n = 0;
1830 for (i = 0; i < dynrelcount; i++)
1831 {
1832 p = dynrelbuf[i];
1833 size += strlen ((*p->sym_ptr_ptr)->name) + sizeof ("@plt");
1834 if (p->addend != 0)
1835 size += sizeof ("+0x") - 1 + 8 + 8 * ABI_64_P (abfd);
1836 }
1837
1838 s = *ret = (asymbol *) bfd_zmalloc (size);
1839 if (s == NULL)
1840 goto bad_return;
1841
1842 bed = get_elf_backend_data (abfd);
1843
1844 if (bed->target_id == X86_64_ELF_DATA)
1845 {
1846 get_plt_got_vma = elf_x86_64_get_plt_got_vma;
1847 valid_plt_reloc_p = elf_x86_64_valid_plt_reloc_p;
1848 }
1849 else
1850 {
1851 get_plt_got_vma = elf_i386_get_plt_got_vma;
1852 valid_plt_reloc_p = elf_i386_valid_plt_reloc_p;
1853 if (got_addr)
1854 {
1855 /* Check .got.plt and then .got to get the _GLOBAL_OFFSET_TABLE_
1856 address. */
1857 asection *sec = bfd_get_section_by_name (abfd, ".got.plt");
1858 if (sec != NULL)
1859 got_addr = sec->vma;
1860 else
1861 {
1862 sec = bfd_get_section_by_name (abfd, ".got");
1863 if (sec != NULL)
1864 got_addr = sec->vma;
1865 }
1866
1867 if (got_addr == (bfd_vma) -1)
1868 goto bad_return;
1869 }
1870 }
1871
1872 /* Check for each PLT section. */
1873 names = (char *) (s + count);
1874 size = 0;
1875 n = 0;
1876 for (j = 0; plts[j].name != NULL; j++)
1877 if ((plt_contents = plts[j].contents) != NULL)
1878 {
1879 long k;
1880 bfd_vma offset;
1881 asection *plt;
1882 struct elf_x86_plt *plt_p = &plts[j];
1883
1884 plt_got_offset = plt_p->plt_got_offset;
1885 plt_entry_size = plt_p->plt_entry_size;
1886
1887 plt = plt_p->sec;
1888
1889 if ((plt_p->type & plt_lazy))
1890 {
1891 /* Skip PLT0 in lazy PLT. */
1892 k = 1;
1893 offset = plt_entry_size;
1894 }
1895 else
1896 {
1897 k = 0;
1898 offset = 0;
1899 }
1900
1901 /* Check each PLT entry against dynamic relocations. */
1902 for (; k < plt_p->count; k++)
1903 {
1904 int off;
1905 bfd_vma got_vma;
1906 long min, max, mid;
1907
1908 /* Get the GOT offset for i386 or the PC-relative offset
1909 for x86-64, a signed 32-bit integer. */
1910 off = H_GET_32 (abfd, (plt_contents + offset
1911 + plt_got_offset));
1912 got_vma = get_plt_got_vma (plt_p, off, offset, got_addr);
1913
1914 /* Binary search. */
1915 p = dynrelbuf[0];
1916 min = 0;
1917 max = dynrelcount;
1918 while ((min + 1) < max)
1919 {
1920 arelent *r;
1921
1922 mid = (min + max) / 2;
1923 r = dynrelbuf[mid];
1924 if (got_vma > r->address)
1925 min = mid;
1926 else if (got_vma < r->address)
1927 max = mid;
1928 else
1929 {
1930 p = r;
1931 break;
1932 }
1933 }
1934
1935 /* Skip unknown relocation. PR 17512: file: bc9d6cf5. */
1936 if (got_vma == p->address
1937 && p->howto != NULL
1938 && valid_plt_reloc_p (p->howto->type))
1939 {
1940 *s = **p->sym_ptr_ptr;
1941 /* Undefined syms won't have BSF_LOCAL or BSF_GLOBAL
1942 set. Since we are defining a symbol, ensure one
1943 of them is set. */
1944 if ((s->flags & BSF_LOCAL) == 0)
1945 s->flags |= BSF_GLOBAL;
1946 s->flags |= BSF_SYNTHETIC;
1947 /* This is no longer a section symbol. */
1948 s->flags &= ~BSF_SECTION_SYM;
1949 s->section = plt;
1950 s->the_bfd = plt->owner;
1951 s->value = offset;
1952 s->udata.p = NULL;
1953 s->name = names;
1954 len = strlen ((*p->sym_ptr_ptr)->name);
1955 memcpy (names, (*p->sym_ptr_ptr)->name, len);
1956 names += len;
1957 if (p->addend != 0)
1958 {
1959 char buf[30], *a;
1960
1961 memcpy (names, "+0x", sizeof ("+0x") - 1);
1962 names += sizeof ("+0x") - 1;
1963 bfd_sprintf_vma (abfd, buf, p->addend);
1964 for (a = buf; *a == '0'; ++a)
1965 ;
1966 size = strlen (a);
1967 memcpy (names, a, size);
1968 names += size;
1969 }
1970 memcpy (names, "@plt", sizeof ("@plt"));
1971 names += sizeof ("@plt");
1972 n++;
1973 s++;
1974 }
1975 offset += plt_entry_size;
1976 }
1977 }
1978
1979 /* PLT entries with R_386_TLS_DESC relocations are skipped. */
1980 if (n == 0)
1981 {
1982bad_return:
1983 count = -1;
1984 }
1985 else
1986 count = n;
1987
1988 for (j = 0; plts[j].name != NULL; j++)
1989 if (plts[j].contents != NULL)
1990 free (plts[j].contents);
1991
1992 free (dynrelbuf);
1993
1994 return count;
1995}
1996
0afcef53
L
1997/* Parse x86 GNU properties. */
1998
1999enum elf_property_kind
2000_bfd_x86_elf_parse_gnu_properties (bfd *abfd, unsigned int type,
2001 bfd_byte *ptr, unsigned int datasz)
2002{
2003 elf_property *prop;
2004
2005 switch (type)
2006 {
2007 case GNU_PROPERTY_X86_ISA_1_USED:
2008 case GNU_PROPERTY_X86_ISA_1_NEEDED:
2009 case GNU_PROPERTY_X86_FEATURE_1_AND:
2010 if (datasz != 4)
2011 {
2012 _bfd_error_handler
2013 ((type == GNU_PROPERTY_X86_ISA_1_USED
2014 ? _("error: %B: <corrupt x86 ISA used size: 0x%x>")
2015 : (type == GNU_PROPERTY_X86_ISA_1_NEEDED
2016 ? _("error: %B: <corrupt x86 ISA needed size: 0x%x>")
2017 : _("error: %B: <corrupt x86 feature size: 0x%x>"))),
2018 abfd, datasz);
2019 return property_corrupt;
2020 }
2021 prop = _bfd_elf_get_property (abfd, type, datasz);
2022 /* Combine properties of the same type. */
2023 prop->u.number |= bfd_h_get_32 (abfd, ptr);
2024 prop->pr_kind = property_number;
2025 break;
2026
2027 default:
2028 return property_ignored;
2029 }
2030
2031 return property_number;
2032}
2033
2034/* Merge x86 GNU property BPROP with APROP. If APROP isn't NULL,
2035 return TRUE if APROP is updated. Otherwise, return TRUE if BPROP
2036 should be merged with ABFD. */
2037
2038bfd_boolean
2039_bfd_x86_elf_merge_gnu_properties (struct bfd_link_info *info,
2040 bfd *abfd ATTRIBUTE_UNUSED,
2041 elf_property *aprop,
2042 elf_property *bprop)
2043{
2044 unsigned int number, features;
2045 bfd_boolean updated = FALSE;
2046 unsigned int pr_type = aprop != NULL ? aprop->pr_type : bprop->pr_type;
2047
2048 switch (pr_type)
2049 {
2050 case GNU_PROPERTY_X86_ISA_1_USED:
2051 case GNU_PROPERTY_X86_ISA_1_NEEDED:
2052 if (aprop != NULL && bprop != NULL)
2053 {
2054 number = aprop->u.number;
2055 aprop->u.number = number | bprop->u.number;
2056 updated = number != (unsigned int) aprop->u.number;
2057 }
2058 else
2059 {
2060 /* Return TRUE if APROP is NULL to indicate that BPROP should
2061 be added to ABFD. */
2062 updated = aprop == NULL;
2063 }
2064 break;
2065
2066 case GNU_PROPERTY_X86_FEATURE_1_AND:
2067 /* Only one of APROP and BPROP can be NULL:
2068 1. APROP & BPROP when both APROP and BPROP aren't NULL.
2069 2. If APROP is NULL, remove x86 feature.
2070 3. Otherwise, do nothing.
2071 */
2072 if (aprop != NULL && bprop != NULL)
2073 {
2074 features = 0;
2075 if (info->ibt)
2076 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2077 if (info->shstk)
2078 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2079 number = aprop->u.number;
2080 /* Add GNU_PROPERTY_X86_FEATURE_1_IBT and
2081 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2082 aprop->u.number = (number & bprop->u.number) | features;
2083 updated = number != (unsigned int) aprop->u.number;
2084 /* Remove the property if all feature bits are cleared. */
2085 if (aprop->u.number == 0)
2086 aprop->pr_kind = property_remove;
2087 }
2088 else
2089 {
2090 features = 0;
2091 if (info->ibt)
2092 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2093 if (info->shstk)
2094 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2095 if (features)
2096 {
2097 /* Add GNU_PROPERTY_X86_FEATURE_1_IBT and
2098 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2099 if (aprop != NULL)
2100 {
2101 number = aprop->u.number;
2102 aprop->u.number = number | features;
2103 updated = number != (unsigned int) aprop->u.number;
2104 }
2105 else
2106 {
2107 bprop->u.number |= features;
2108 updated = TRUE;
2109 }
2110 }
2111 else if (aprop != NULL)
2112 {
2113 aprop->pr_kind = property_remove;
2114 updated = TRUE;
2115 }
2116 }
2117 break;
2118
2119 default:
2120 /* Never should happen. */
2121 abort ();
2122 }
2123
2124 return updated;
2125}
a6798bab
L
2126
2127/* Set up x86 GNU properties. Return the first relocatable ELF input
2128 with GNU properties if found. Otherwise, return NULL. */
2129
2130bfd *
2131_bfd_x86_elf_link_setup_gnu_properties
1de031c8 2132 (struct bfd_link_info *info, struct elf_x86_init_table *init_table)
a6798bab
L
2133{
2134 bfd_boolean normal_target;
2135 bfd_boolean lazy_plt;
2136 asection *sec, *pltsec;
2137 bfd *dynobj;
2138 bfd_boolean use_ibt_plt;
2139 unsigned int plt_alignment, features;
2140 struct elf_x86_link_hash_table *htab;
2141 bfd *pbfd;
2142 bfd *ebfd = NULL;
2143 elf_property *prop;
2144 const struct elf_backend_data *bed;
2145 unsigned int class_align = ABI_64_P (info->output_bfd) ? 3 : 2;
2146 unsigned int got_align;
2147
2148 features = 0;
2149 if (info->ibt)
2150 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2151 if (info->shstk)
2152 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2153
2154 /* Find a normal input file with GNU property note. */
2155 for (pbfd = info->input_bfds;
2156 pbfd != NULL;
2157 pbfd = pbfd->link.next)
2158 if (bfd_get_flavour (pbfd) == bfd_target_elf_flavour
2159 && bfd_count_sections (pbfd) != 0)
2160 {
2161 ebfd = pbfd;
2162
2163 if (elf_properties (pbfd) != NULL)
2164 break;
2165 }
2166
2167 if (ebfd != NULL && features)
2168 {
2169 /* If features is set, add GNU_PROPERTY_X86_FEATURE_1_IBT and
2170 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2171 prop = _bfd_elf_get_property (ebfd,
2172 GNU_PROPERTY_X86_FEATURE_1_AND,
2173 4);
2174 prop->u.number |= features;
2175 prop->pr_kind = property_number;
2176
2177 /* Create the GNU property note section if needed. */
2178 if (pbfd == NULL)
2179 {
2180 sec = bfd_make_section_with_flags (ebfd,
2181 NOTE_GNU_PROPERTY_SECTION_NAME,
2182 (SEC_ALLOC
2183 | SEC_LOAD
2184 | SEC_IN_MEMORY
2185 | SEC_READONLY
2186 | SEC_HAS_CONTENTS
2187 | SEC_DATA));
2188 if (sec == NULL)
2189 info->callbacks->einfo (_("%F: failed to create GNU property section\n"));
2190
2191 if (!bfd_set_section_alignment (ebfd, sec, class_align))
2192 {
2193error_alignment:
2194 info->callbacks->einfo (_("%F%A: failed to align section\n"),
2195 sec);
2196 }
2197
2198 elf_section_type (sec) = SHT_NOTE;
2199 }
2200 }
2201
2202 pbfd = _bfd_elf_link_setup_gnu_properties (info);
2203
a6798bab
L
2204 bed = get_elf_backend_data (info->output_bfd);
2205
2206 htab = elf_x86_hash_table (info, bed->target_id);
2207 if (htab == NULL)
2208 return pbfd;
2209
1de031c8
L
2210 htab->is_vxworks = init_table->is_vxworks;
2211 htab->r_info = init_table->r_info;
2212 htab->r_sym = init_table->r_sym;
7a382c1c
L
2213
2214 if (bfd_link_relocatable (info))
2215 return pbfd;
eeb2f20a 2216
a6798bab
L
2217 use_ibt_plt = info->ibtplt || info->ibt;
2218 if (!use_ibt_plt && pbfd != NULL)
2219 {
2220 /* Check if GNU_PROPERTY_X86_FEATURE_1_IBT is on. */
2221 elf_property_list *p;
2222
2223 /* The property list is sorted in order of type. */
2224 for (p = elf_properties (pbfd); p; p = p->next)
2225 {
2226 if (GNU_PROPERTY_X86_FEATURE_1_AND == p->property.pr_type)
2227 {
2228 use_ibt_plt = !!(p->property.u.number
2229 & GNU_PROPERTY_X86_FEATURE_1_IBT);
2230 break;
2231 }
2232 else if (GNU_PROPERTY_X86_FEATURE_1_AND < p->property.pr_type)
2233 break;
2234 }
2235 }
2236
2237 dynobj = htab->elf.dynobj;
2238
2239 /* Set htab->elf.dynobj here so that there is no need to check and
2240 set it in check_relocs. */
2241 if (dynobj == NULL)
2242 {
2243 if (pbfd != NULL)
2244 {
2245 htab->elf.dynobj = pbfd;
2246 dynobj = pbfd;
2247 }
2248 else
2249 {
2250 bfd *abfd;
2251
2252 /* Find a normal input file to hold linker created
2253 sections. */
2254 for (abfd = info->input_bfds;
2255 abfd != NULL;
2256 abfd = abfd->link.next)
2257 if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
2258 && (abfd->flags
2259 & (DYNAMIC | BFD_LINKER_CREATED | BFD_PLUGIN)) == 0)
2260 {
2261 htab->elf.dynobj = abfd;
2262 dynobj = abfd;
2263 break;
2264 }
2265 }
2266 }
2267
2268 /* Even when lazy binding is disabled by "-z now", the PLT0 entry may
2269 still be used with LD_AUDIT or LD_PROFILE if PLT entry is used for
2270 canonical function address. */
2271 htab->plt.has_plt0 = 1;
1de031c8 2272 normal_target = init_table->normal_target;
a6798bab
L
2273
2274 if (normal_target)
2275 {
2276 if (use_ibt_plt)
2277 {
1de031c8
L
2278 htab->lazy_plt = init_table->lazy_ibt_plt;
2279 htab->non_lazy_plt = init_table->non_lazy_ibt_plt;
a6798bab
L
2280 }
2281 else
2282 {
1de031c8
L
2283 htab->lazy_plt = init_table->lazy_plt;
2284 htab->non_lazy_plt = init_table->non_lazy_plt;
a6798bab
L
2285 }
2286 }
2287 else
2288 {
1de031c8 2289 htab->lazy_plt = init_table->lazy_plt;
a6798bab
L
2290 htab->non_lazy_plt = NULL;
2291 }
2292
2293 pltsec = htab->elf.splt;
2294
2295 /* If the non-lazy PLT is available, use it for all PLT entries if
2296 there are no PLT0 or no .plt section. */
2297 if (htab->non_lazy_plt != NULL
2298 && (!htab->plt.has_plt0 || pltsec == NULL))
2299 {
2300 lazy_plt = FALSE;
2301 if (bfd_link_pic (info))
2302 htab->plt.plt_entry = htab->non_lazy_plt->pic_plt_entry;
2303 else
2304 htab->plt.plt_entry = htab->non_lazy_plt->plt_entry;
2305 htab->plt.plt_entry_size = htab->non_lazy_plt->plt_entry_size;
2306 htab->plt.plt_got_offset = htab->non_lazy_plt->plt_got_offset;
2307 htab->plt.plt_got_insn_size
2308 = htab->non_lazy_plt->plt_got_insn_size;
2309 htab->plt.eh_frame_plt_size
2310 = htab->non_lazy_plt->eh_frame_plt_size;
2311 htab->plt.eh_frame_plt = htab->non_lazy_plt->eh_frame_plt;
2312 }
2313 else
2314 {
2315 lazy_plt = TRUE;
2316 if (bfd_link_pic (info))
2317 {
2318 htab->plt.plt0_entry = htab->lazy_plt->pic_plt0_entry;
2319 htab->plt.plt_entry = htab->lazy_plt->pic_plt_entry;
2320 }
2321 else
2322 {
2323 htab->plt.plt0_entry = htab->lazy_plt->plt0_entry;
2324 htab->plt.plt_entry = htab->lazy_plt->plt_entry;
2325 }
2326 htab->plt.plt_entry_size = htab->lazy_plt->plt_entry_size;
2327 htab->plt.plt_got_offset = htab->lazy_plt->plt_got_offset;
2328 htab->plt.plt_got_insn_size
2329 = htab->lazy_plt->plt_got_insn_size;
2330 htab->plt.eh_frame_plt_size
2331 = htab->lazy_plt->eh_frame_plt_size;
2332 htab->plt.eh_frame_plt = htab->lazy_plt->eh_frame_plt;
2333 }
2334
2335 /* Return if there are no normal input files. */
2336 if (dynobj == NULL)
2337 return pbfd;
2338
eeb2f20a 2339 if (htab->is_vxworks
a6798bab
L
2340 && !elf_vxworks_create_dynamic_sections (dynobj, info,
2341 &htab->srelplt2))
2342 {
2343 info->callbacks->einfo (_("%F: failed to create VxWorks dynamic sections\n"));
2344 return pbfd;
2345 }
2346
2347 /* Since create_dynamic_sections isn't always called, but GOT
2348 relocations need GOT relocations, create them here so that we
2349 don't need to do it in check_relocs. */
2350 if (htab->elf.sgot == NULL
2351 && !_bfd_elf_create_got_section (dynobj, info))
2352 info->callbacks->einfo (_("%F: failed to create GOT sections\n"));
2353
2354 got_align = (bed->target_id == X86_64_ELF_DATA) ? 3 : 2;
2355
2356 /* Align .got and .got.plt sections to their entry size. Do it here
2357 instead of in create_dynamic_sections so that they are always
2358 properly aligned even if create_dynamic_sections isn't called. */
2359 sec = htab->elf.sgot;
2360 if (!bfd_set_section_alignment (dynobj, sec, got_align))
2361 goto error_alignment;
2362
2363 sec = htab->elf.sgotplt;
2364 if (!bfd_set_section_alignment (dynobj, sec, got_align))
2365 goto error_alignment;
2366
2367 /* Create the ifunc sections here so that check_relocs can be
2368 simplified. */
2369 if (!_bfd_elf_create_ifunc_sections (dynobj, info))
2370 info->callbacks->einfo (_("%F: failed to create ifunc sections\n"));
2371
2372 plt_alignment = bfd_log2 (htab->plt.plt_entry_size);
2373
2374 if (pltsec != NULL)
2375 {
2376 /* Whe creating executable, set the contents of the .interp
2377 section to the interpreter. */
2378 if (bfd_link_executable (info) && !info->nointerp)
2379 {
2380 asection *s = bfd_get_linker_section (dynobj, ".interp");
2381 if (s == NULL)
2382 abort ();
2383 s->size = htab->dynamic_interpreter_size;
2384 s->contents = (unsigned char *) htab->dynamic_interpreter;
2385 htab->interp = s;
2386 }
2387
2388 /* Don't change PLT section alignment for NaCl since it uses
2389 64-byte PLT entry and sets PLT section alignment to 32
2390 bytes. Don't create additional PLT sections for NaCl. */
2391 if (normal_target)
2392 {
2393 flagword pltflags = (bed->dynamic_sec_flags
2394 | SEC_ALLOC
2395 | SEC_CODE
2396 | SEC_LOAD
2397 | SEC_READONLY);
2398 unsigned int non_lazy_plt_alignment
2399 = bfd_log2 (htab->non_lazy_plt->plt_entry_size);
2400
2401 sec = pltsec;
2402 if (!bfd_set_section_alignment (sec->owner, sec,
2403 plt_alignment))
2404 goto error_alignment;
2405
2406 /* Create the GOT procedure linkage table. */
2407 sec = bfd_make_section_anyway_with_flags (dynobj,
2408 ".plt.got",
2409 pltflags);
2410 if (sec == NULL)
2411 info->callbacks->einfo (_("%F: failed to create GOT PLT section\n"));
2412
2413 if (!bfd_set_section_alignment (dynobj, sec,
2414 non_lazy_plt_alignment))
2415 goto error_alignment;
2416
2417 htab->plt_got = sec;
2418
2419 if (lazy_plt)
2420 {
2421 sec = NULL;
2422
2423 if (use_ibt_plt)
2424 {
2425 /* Create the second PLT for Intel IBT support. IBT
2426 PLT is supported only for non-NaCl target and is
2427 is needed only for lazy binding. */
2428 sec = bfd_make_section_anyway_with_flags (dynobj,
2429 ".plt.sec",
2430 pltflags);
2431 if (sec == NULL)
2432 info->callbacks->einfo (_("%F: failed to create IBT-enabled PLT section\n"));
2433
2434 if (!bfd_set_section_alignment (dynobj, sec,
2435 plt_alignment))
2436 goto error_alignment;
2437 }
2438 else if (info->bndplt && ABI_64_P (dynobj))
2439 {
2440 /* Create the second PLT for Intel MPX support. MPX
2441 PLT is supported only for non-NaCl target in 64-bit
2442 mode and is needed only for lazy binding. */
2443 sec = bfd_make_section_anyway_with_flags (dynobj,
2444 ".plt.sec",
2445 pltflags);
2446 if (sec == NULL)
2447 info->callbacks->einfo (_("%F: failed to create BND PLT section\n"));
2448
2449 if (!bfd_set_section_alignment (dynobj, sec,
2450 non_lazy_plt_alignment))
2451 goto error_alignment;
2452 }
2453
2454 htab->plt_second = sec;
2455 }
2456 }
2457
2458 if (!info->no_ld_generated_unwind_info)
2459 {
2460 flagword flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY
2461 | SEC_HAS_CONTENTS | SEC_IN_MEMORY
2462 | SEC_LINKER_CREATED);
2463
2464 sec = bfd_make_section_anyway_with_flags (dynobj,
2465 ".eh_frame",
2466 flags);
2467 if (sec == NULL)
2468 info->callbacks->einfo (_("%F: failed to create PLT .eh_frame section\n"));
2469
2470 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2471 goto error_alignment;
2472
2473 htab->plt_eh_frame = sec;
2474
2475 if (htab->plt_got != NULL)
2476 {
2477 sec = bfd_make_section_anyway_with_flags (dynobj,
2478 ".eh_frame",
2479 flags);
2480 if (sec == NULL)
2481 info->callbacks->einfo (_("%F: failed to create GOT PLT .eh_frame section\n"));
2482
2483 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2484 goto error_alignment;
2485
2486 htab->plt_got_eh_frame = sec;
2487 }
2488
2489 if (htab->plt_second != NULL)
2490 {
2491 sec = bfd_make_section_anyway_with_flags (dynobj,
2492 ".eh_frame",
2493 flags);
2494 if (sec == NULL)
2495 info->callbacks->einfo (_("%F: failed to create the second PLT .eh_frame section\n"));
2496
2497 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2498 goto error_alignment;
2499
2500 htab->plt_second_eh_frame = sec;
2501 }
2502 }
2503 }
2504
2505 if (normal_target)
2506 {
2507 /* The .iplt section is used for IFUNC symbols in static
2508 executables. */
2509 sec = htab->elf.iplt;
2510 if (sec != NULL
2511 && !bfd_set_section_alignment (sec->owner, sec,
2512 plt_alignment))
2513 goto error_alignment;
2514 }
2515
2516 return pbfd;
2517}
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