x86; Don't add elf64-x86-64.lo nor elf64.lo together with elfxx-x86.lo
[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"
765e526c
L
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
39946cc2
L
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
b9ce864c
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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,
b9ce864c
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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))
0e30d991
L
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 }
b9ce864c
L
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
0afcef53
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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
L
577/* Allocate space in .plt, .got and associated reloc sections for
578 local dynamic relocs. */
579
5e2ac45d
L
580static bfd_boolean
581elf_x86_allocate_local_dynreloc (void **slot, void *inf)
b9ce864c
L
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
L
594}
595
0afcef53
L
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 {
848 struct elf_link_hash_entry *h
849 = elf_link_hash_lookup (elf_hash_table (info),
850 htab->tls_get_addr,
851 FALSE, FALSE, FALSE);
852 if (h != NULL)
853 ((struct elf_x86_link_hash_entry *) h)->tls_get_addr = 1;
854 }
855 }
856
857 /* Invoke the regular ELF backend linker to do all the work. */
858 return _bfd_elf_link_check_relocs (abfd, info);
859}
860
5e2ac45d
L
861/* Set the sizes of the dynamic sections. */
862
863bfd_boolean
864_bfd_x86_elf_size_dynamic_sections (bfd *output_bfd,
865 struct bfd_link_info *info)
866{
867 struct elf_x86_link_hash_table *htab;
868 bfd *dynobj;
869 asection *s;
870 bfd_boolean relocs;
871 bfd *ibfd;
872 const struct elf_backend_data *bed
873 = get_elf_backend_data (output_bfd);
874
875 htab = elf_x86_hash_table (info, bed->target_id);
876 if (htab == NULL)
877 return FALSE;
878 dynobj = htab->elf.dynobj;
879 if (dynobj == NULL)
880 abort ();
881
882 /* Set up .got offsets for local syms, and space for local dynamic
883 relocs. */
884 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
885 {
886 bfd_signed_vma *local_got;
887 bfd_signed_vma *end_local_got;
888 char *local_tls_type;
889 bfd_vma *local_tlsdesc_gotent;
890 bfd_size_type locsymcount;
891 Elf_Internal_Shdr *symtab_hdr;
892 asection *srel;
893
894 if (! is_x86_elf (ibfd, htab))
895 continue;
896
897 for (s = ibfd->sections; s != NULL; s = s->next)
898 {
899 struct elf_dyn_relocs *p;
900
5e2ac45d
L
901 for (p = ((struct elf_dyn_relocs *)
902 elf_section_data (s)->local_dynrel);
903 p != NULL;
904 p = p->next)
905 {
906 if (!bfd_is_abs_section (p->sec)
907 && bfd_is_abs_section (p->sec->output_section))
908 {
909 /* Input section has been discarded, either because
910 it is a copy of a linkonce section or due to
911 linker script /DISCARD/, so we'll be discarding
912 the relocs too. */
913 }
914 else if (htab->is_vxworks
915 && strcmp (p->sec->output_section->name,
916 ".tls_vars") == 0)
917 {
918 /* Relocations in vxworks .tls_vars sections are
919 handled specially by the loader. */
920 }
921 else if (p->count != 0)
922 {
923 srel = elf_section_data (p->sec)->sreloc;
924 srel->size += p->count * htab->sizeof_reloc;
925 if ((p->sec->output_section->flags & SEC_READONLY) != 0
926 && (info->flags & DF_TEXTREL) == 0)
927 {
928 info->flags |= DF_TEXTREL;
929 if ((info->warn_shared_textrel && bfd_link_pic (info))
930 || info->error_textrel)
931 /* xgettext:c-format */
932 info->callbacks->einfo (_("%P: %B: warning: relocation in readonly section `%A'\n"),
933 p->sec->owner, p->sec);
934 }
935 }
936 }
937 }
938
939 local_got = elf_local_got_refcounts (ibfd);
940 if (!local_got)
941 continue;
942
943 symtab_hdr = &elf_symtab_hdr (ibfd);
944 locsymcount = symtab_hdr->sh_info;
945 end_local_got = local_got + locsymcount;
946 local_tls_type = elf_x86_local_got_tls_type (ibfd);
947 local_tlsdesc_gotent = elf_x86_local_tlsdesc_gotent (ibfd);
948 s = htab->elf.sgot;
949 srel = htab->elf.srelgot;
950 for (; local_got < end_local_got;
951 ++local_got, ++local_tls_type, ++local_tlsdesc_gotent)
952 {
953 *local_tlsdesc_gotent = (bfd_vma) -1;
954 if (*local_got > 0)
955 {
956 if (GOT_TLS_GDESC_P (*local_tls_type))
957 {
958 *local_tlsdesc_gotent = htab->elf.sgotplt->size
959 - elf_x86_compute_jump_table_size (htab);
960 htab->elf.sgotplt->size += 2 * htab->got_entry_size;
961 *local_got = (bfd_vma) -2;
962 }
963 if (! GOT_TLS_GDESC_P (*local_tls_type)
964 || GOT_TLS_GD_P (*local_tls_type))
965 {
966 *local_got = s->size;
967 s->size += htab->got_entry_size;
968 if (GOT_TLS_GD_P (*local_tls_type)
969 || *local_tls_type == GOT_TLS_IE_BOTH)
970 s->size += htab->got_entry_size;
971 }
972 if (bfd_link_pic (info)
973 || GOT_TLS_GD_ANY_P (*local_tls_type)
974 || (*local_tls_type & GOT_TLS_IE))
975 {
976 if (*local_tls_type == GOT_TLS_IE_BOTH)
977 srel->size += 2 * htab->sizeof_reloc;
978 else if (GOT_TLS_GD_P (*local_tls_type)
979 || ! GOT_TLS_GDESC_P (*local_tls_type))
980 srel->size += htab->sizeof_reloc;
981 if (GOT_TLS_GDESC_P (*local_tls_type))
982 {
983 htab->elf.srelplt->size += htab->sizeof_reloc;
984 if (bed->target_id == X86_64_ELF_DATA)
985 htab->tlsdesc_plt = (bfd_vma) -1;
986 }
987 }
988 }
989 else
990 *local_got = (bfd_vma) -1;
991 }
992 }
993
994 if (htab->tls_ld_or_ldm_got.refcount > 0)
995 {
996 /* Allocate 2 got entries and 1 dynamic reloc for R_386_TLS_LDM
997 or R_X86_64_TLSLD relocs. */
998 htab->tls_ld_or_ldm_got.offset = htab->elf.sgot->size;
999 htab->elf.sgot->size += 2 * htab->got_entry_size;
1000 htab->elf.srelgot->size += htab->sizeof_reloc;
1001 }
1002 else
1003 htab->tls_ld_or_ldm_got.offset = -1;
1004
1005 /* Allocate global sym .plt and .got entries, and space for global
1006 sym dynamic relocs. */
1007 elf_link_hash_traverse (&htab->elf, elf_x86_allocate_dynrelocs,
1008 info);
1009
1010 /* Allocate .plt and .got entries, and space for local symbols. */
1011 htab_traverse (htab->loc_hash_table, elf_x86_allocate_local_dynreloc,
1012 info);
1013
1014 /* For every jump slot reserved in the sgotplt, reloc_count is
1015 incremented. However, when we reserve space for TLS descriptors,
1016 it's not incremented, so in order to compute the space reserved
1017 for them, it suffices to multiply the reloc count by the jump
1018 slot size.
1019
1020 PR ld/13302: We start next_irelative_index at the end of .rela.plt
1021 so that R_{386,X86_64}_IRELATIVE entries come last. */
1022 if (htab->elf.srelplt)
1023 {
1024 htab->next_tls_desc_index = htab->elf.srelplt->reloc_count;
1025 htab->sgotplt_jump_table_size
1026 = elf_x86_compute_jump_table_size (htab);
1027 htab->next_irelative_index = htab->elf.srelplt->reloc_count - 1;
1028 }
1029 else if (htab->elf.irelplt)
1030 htab->next_irelative_index = htab->elf.irelplt->reloc_count - 1;
1031
1032 if (htab->tlsdesc_plt)
1033 {
1034 /* NB: tlsdesc_plt is set only for x86-64. If we're not using
1035 lazy TLS relocations, don't generate the PLT and GOT entries
1036 they require. */
1037 if ((info->flags & DF_BIND_NOW))
1038 htab->tlsdesc_plt = 0;
1039 else
1040 {
1041 htab->tlsdesc_got = htab->elf.sgot->size;
1042 htab->elf.sgot->size += htab->got_entry_size;
1043 /* Reserve room for the initial entry.
1044 FIXME: we could probably do away with it in this case. */
1045 if (htab->elf.splt->size == 0)
1046 htab->elf.splt->size = htab->plt.plt_entry_size;
1047 htab->tlsdesc_plt = htab->elf.splt->size;
1048 htab->elf.splt->size += htab->plt.plt_entry_size;
1049 }
1050 }
1051
1052 if (htab->elf.sgotplt)
1053 {
1054 /* Don't allocate .got.plt section if there are no GOT nor PLT
1055 entries and there is no reference to _GLOBAL_OFFSET_TABLE_. */
1056 if ((htab->elf.hgot == NULL
1057 || !htab->elf.hgot->ref_regular_nonweak)
1058 && (htab->elf.sgotplt->size == bed->got_header_size)
1059 && (htab->elf.splt == NULL
1060 || htab->elf.splt->size == 0)
1061 && (htab->elf.sgot == NULL
1062 || htab->elf.sgot->size == 0)
1063 && (htab->elf.iplt == NULL
1064 || htab->elf.iplt->size == 0)
1065 && (htab->elf.igotplt == NULL
1066 || htab->elf.igotplt->size == 0))
1067 htab->elf.sgotplt->size = 0;
1068 }
1069
1070 if (_bfd_elf_eh_frame_present (info))
1071 {
1072 if (htab->plt_eh_frame != NULL
1073 && htab->elf.splt != NULL
1074 && htab->elf.splt->size != 0
1075 && !bfd_is_abs_section (htab->elf.splt->output_section))
1076 htab->plt_eh_frame->size = htab->plt.eh_frame_plt_size;
1077
1078 if (htab->plt_got_eh_frame != NULL
1079 && htab->plt_got != NULL
1080 && htab->plt_got->size != 0
1081 && !bfd_is_abs_section (htab->plt_got->output_section))
1082 htab->plt_got_eh_frame->size
1083 = htab->non_lazy_plt->eh_frame_plt_size;
1084
1085 /* Unwind info for the second PLT and .plt.got sections are
1086 identical. */
1087 if (htab->plt_second_eh_frame != NULL
1088 && htab->plt_second != NULL
1089 && htab->plt_second->size != 0
1090 && !bfd_is_abs_section (htab->plt_second->output_section))
1091 htab->plt_second_eh_frame->size
1092 = htab->non_lazy_plt->eh_frame_plt_size;
1093 }
1094
1095 /* We now have determined the sizes of the various dynamic sections.
1096 Allocate memory for them. */
1097 relocs = FALSE;
1098 for (s = dynobj->sections; s != NULL; s = s->next)
1099 {
1100 bfd_boolean strip_section = TRUE;
1101
1102 if ((s->flags & SEC_LINKER_CREATED) == 0)
1103 continue;
1104
1105 if (s == htab->elf.splt
1106 || s == htab->elf.sgot)
1107 {
1108 /* Strip this section if we don't need it; see the
1109 comment below. */
1110 /* We'd like to strip these sections if they aren't needed, but if
1111 we've exported dynamic symbols from them we must leave them.
1112 It's too late to tell BFD to get rid of the symbols. */
1113
1114 if (htab->elf.hplt != NULL)
1115 strip_section = FALSE;
1116 }
1117 else if (s == htab->elf.sgotplt
1118 || s == htab->elf.iplt
1119 || s == htab->elf.igotplt
1120 || s == htab->plt_second
1121 || s == htab->plt_got
1122 || s == htab->plt_eh_frame
1123 || s == htab->plt_got_eh_frame
1124 || s == htab->plt_second_eh_frame
1125 || s == htab->elf.sdynbss
1126 || s == htab->elf.sdynrelro)
1127 {
1128 /* Strip these too. */
1129 }
1130 else if (htab->is_reloc_section (bfd_get_section_name (dynobj, s)))
1131 {
1132 if (s->size != 0
1133 && s != htab->elf.srelplt
1134 && s != htab->srelplt2)
1135 relocs = TRUE;
1136
1137 /* We use the reloc_count field as a counter if we need
1138 to copy relocs into the output file. */
1139 if (s != htab->elf.srelplt)
1140 s->reloc_count = 0;
1141 }
1142 else
1143 {
1144 /* It's not one of our sections, so don't allocate space. */
1145 continue;
1146 }
1147
1148 if (s->size == 0)
1149 {
1150 /* If we don't need this section, strip it from the
1151 output file. This is mostly to handle .rel.bss and
1152 .rel.plt. We must create both sections in
1153 create_dynamic_sections, because they must be created
1154 before the linker maps input sections to output
1155 sections. The linker does that before
1156 adjust_dynamic_symbol is called, and it is that
1157 function which decides whether anything needs to go
1158 into these sections. */
1159 if (strip_section)
1160 s->flags |= SEC_EXCLUDE;
1161 continue;
1162 }
1163
1164 if ((s->flags & SEC_HAS_CONTENTS) == 0)
1165 continue;
1166
1167 /* Allocate memory for the section contents. We use bfd_zalloc
1168 here in case unused entries are not reclaimed before the
1169 section's contents are written out. This should not happen,
1170 but this way if it does, we get a R_386_NONE or R_X86_64_NONE
1171 reloc instead of garbage. */
1172 s->contents = (unsigned char *) bfd_zalloc (dynobj, s->size);
1173 if (s->contents == NULL)
1174 return FALSE;
1175 }
1176
1177 if (htab->plt_eh_frame != NULL
1178 && htab->plt_eh_frame->contents != NULL)
1179 {
1180 memcpy (htab->plt_eh_frame->contents,
1181 htab->plt.eh_frame_plt,
1182 htab->plt_eh_frame->size);
1183 bfd_put_32 (dynobj, htab->elf.splt->size,
1184 htab->plt_eh_frame->contents + PLT_FDE_LEN_OFFSET);
1185 }
1186
1187 if (htab->plt_got_eh_frame != NULL
1188 && htab->plt_got_eh_frame->contents != NULL)
1189 {
1190 memcpy (htab->plt_got_eh_frame->contents,
1191 htab->non_lazy_plt->eh_frame_plt,
1192 htab->plt_got_eh_frame->size);
1193 bfd_put_32 (dynobj, htab->plt_got->size,
1194 (htab->plt_got_eh_frame->contents
1195 + PLT_FDE_LEN_OFFSET));
1196 }
1197
1198 if (htab->plt_second_eh_frame != NULL
1199 && htab->plt_second_eh_frame->contents != NULL)
1200 {
1201 memcpy (htab->plt_second_eh_frame->contents,
1202 htab->non_lazy_plt->eh_frame_plt,
1203 htab->plt_second_eh_frame->size);
1204 bfd_put_32 (dynobj, htab->plt_second->size,
1205 (htab->plt_second_eh_frame->contents
1206 + PLT_FDE_LEN_OFFSET));
1207 }
1208
1209 if (htab->elf.dynamic_sections_created)
1210 {
1211 /* Add some entries to the .dynamic section. We fill in the
1212 values later, in elf_{i386,x86_64}_finish_dynamic_sections,
1213 but we must add the entries now so that we get the correct
1214 size for the .dynamic section. The DT_DEBUG entry is filled
1215 in by the dynamic linker and used by the debugger. */
1216#define add_dynamic_entry(TAG, VAL) \
1217 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
1218
1219 if (bfd_link_executable (info))
1220 {
1221 if (!add_dynamic_entry (DT_DEBUG, 0))
1222 return FALSE;
1223 }
1224
1225 if (htab->elf.splt->size != 0)
1226 {
1227 /* DT_PLTGOT is used by prelink even if there is no PLT
1228 relocation. */
1229 if (!add_dynamic_entry (DT_PLTGOT, 0))
1230 return FALSE;
1231 }
1232
1233 if (htab->elf.srelplt->size != 0)
1234 {
1235 if (!add_dynamic_entry (DT_PLTRELSZ, 0)
1236 || !add_dynamic_entry (DT_PLTREL, htab->dt_reloc)
1237 || !add_dynamic_entry (DT_JMPREL, 0))
1238 return FALSE;
1239 }
1240
1241 if (htab->tlsdesc_plt
1242 && (!add_dynamic_entry (DT_TLSDESC_PLT, 0)
1243 || !add_dynamic_entry (DT_TLSDESC_GOT, 0)))
1244 return FALSE;
1245
1246 if (relocs)
1247 {
1248 if (!add_dynamic_entry (htab->dt_reloc, 0)
1249 || !add_dynamic_entry (htab->dt_reloc_sz, 0)
1250 || !add_dynamic_entry (htab->dt_reloc_ent,
1251 htab->sizeof_reloc))
1252 return FALSE;
1253
1254 /* If any dynamic relocs apply to a read-only section,
1255 then we need a DT_TEXTREL entry. */
1256 if ((info->flags & DF_TEXTREL) == 0)
1257 elf_link_hash_traverse (&htab->elf,
1258 _bfd_x86_elf_readonly_dynrelocs,
1259 info);
1260
1261 if ((info->flags & DF_TEXTREL) != 0)
1262 {
1263 if (htab->readonly_dynrelocs_against_ifunc)
1264 {
1265 info->callbacks->einfo
1266 (_("%P%X: read-only segment has dynamic IFUNC relocations; recompile with -fPIC\n"));
1267 bfd_set_error (bfd_error_bad_value);
1268 return FALSE;
1269 }
1270
1271 if (!add_dynamic_entry (DT_TEXTREL, 0))
1272 return FALSE;
1273 }
1274 }
1275 if (htab->is_vxworks
1276 && !elf_vxworks_add_dynamic_entries (output_bfd, info))
1277 return FALSE;
1278 }
1279#undef add_dynamic_entry
1280
1281 return TRUE;
1282}
1283
0afcef53
L
1284bfd_boolean
1285_bfd_x86_elf_always_size_sections (bfd *output_bfd,
1286 struct bfd_link_info *info)
1287{
1288 asection *tls_sec = elf_hash_table (info)->tls_sec;
1289
1290 if (tls_sec)
1291 {
1292 struct elf_link_hash_entry *tlsbase;
1293
1294 tlsbase = elf_link_hash_lookup (elf_hash_table (info),
1295 "_TLS_MODULE_BASE_",
1296 FALSE, FALSE, FALSE);
1297
1298 if (tlsbase && tlsbase->type == STT_TLS)
1299 {
1300 struct elf_x86_link_hash_table *htab;
1301 struct bfd_link_hash_entry *bh = NULL;
1302 const struct elf_backend_data *bed
1303 = get_elf_backend_data (output_bfd);
1304
1305 htab = elf_x86_hash_table (info, bed->target_id);
1306 if (htab == NULL)
1307 return FALSE;
1308
1309 if (!(_bfd_generic_link_add_one_symbol
1310 (info, output_bfd, "_TLS_MODULE_BASE_", BSF_LOCAL,
1311 tls_sec, 0, NULL, FALSE,
1312 bed->collect, &bh)))
1313 return FALSE;
1314
1315 htab->tls_module_base = bh;
1316
1317 tlsbase = (struct elf_link_hash_entry *)bh;
1318 tlsbase->def_regular = 1;
1319 tlsbase->other = STV_HIDDEN;
1320 tlsbase->root.linker_def = 1;
1321 (*bed->elf_backend_hide_symbol) (info, tlsbase, TRUE);
1322 }
1323 }
1324
1325 return TRUE;
1326}
1327
1328void
1329_bfd_x86_elf_merge_symbol_attribute (struct elf_link_hash_entry *h,
1330 const Elf_Internal_Sym *isym,
1331 bfd_boolean definition,
1332 bfd_boolean dynamic ATTRIBUTE_UNUSED)
1333{
1334 if (definition)
1335 {
1336 struct elf_x86_link_hash_entry *eh
1337 = (struct elf_x86_link_hash_entry *) h;
1338 eh->def_protected = (ELF_ST_VISIBILITY (isym->st_other)
1339 == STV_PROTECTED);
1340 }
1341}
1342
1343/* Copy the extra info we tack onto an elf_link_hash_entry. */
1344
1345void
1346_bfd_x86_elf_copy_indirect_symbol (struct bfd_link_info *info,
1347 struct elf_link_hash_entry *dir,
1348 struct elf_link_hash_entry *ind)
1349{
1350 struct elf_x86_link_hash_entry *edir, *eind;
1351
1352 edir = (struct elf_x86_link_hash_entry *) dir;
1353 eind = (struct elf_x86_link_hash_entry *) ind;
1354
1355 if (eind->dyn_relocs != NULL)
1356 {
1357 if (edir->dyn_relocs != NULL)
1358 {
1359 struct elf_dyn_relocs **pp;
1360 struct elf_dyn_relocs *p;
1361
1362 /* Add reloc counts against the indirect sym to the direct sym
1363 list. Merge any entries against the same section. */
1364 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
1365 {
1366 struct elf_dyn_relocs *q;
1367
1368 for (q = edir->dyn_relocs; q != NULL; q = q->next)
1369 if (q->sec == p->sec)
1370 {
1371 q->pc_count += p->pc_count;
1372 q->count += p->count;
1373 *pp = p->next;
1374 break;
1375 }
1376 if (q == NULL)
1377 pp = &p->next;
1378 }
1379 *pp = edir->dyn_relocs;
1380 }
1381
1382 edir->dyn_relocs = eind->dyn_relocs;
1383 eind->dyn_relocs = NULL;
1384 }
1385
1386 if (ind->root.type == bfd_link_hash_indirect
1387 && dir->got.refcount <= 0)
1388 {
1389 edir->tls_type = eind->tls_type;
1390 eind->tls_type = GOT_UNKNOWN;
1391 }
1392
1393 /* Copy gotoff_ref so that elf_i386_adjust_dynamic_symbol will
1394 generate a R_386_COPY reloc. */
1395 edir->gotoff_ref |= eind->gotoff_ref;
1396
1397 edir->has_got_reloc |= eind->has_got_reloc;
1398 edir->has_non_got_reloc |= eind->has_non_got_reloc;
1399
1400 if (ELIMINATE_COPY_RELOCS
1401 && ind->root.type != bfd_link_hash_indirect
1402 && dir->dynamic_adjusted)
1403 {
1404 /* If called to transfer flags for a weakdef during processing
1405 of elf_adjust_dynamic_symbol, don't copy non_got_ref.
1406 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
1407 if (dir->versioned != versioned_hidden)
1408 dir->ref_dynamic |= ind->ref_dynamic;
1409 dir->ref_regular |= ind->ref_regular;
1410 dir->ref_regular_nonweak |= ind->ref_regular_nonweak;
1411 dir->needs_plt |= ind->needs_plt;
1412 dir->pointer_equality_needed |= ind->pointer_equality_needed;
1413 }
1414 else
1415 {
1416 if (eind->func_pointer_refcount > 0)
1417 {
1418 edir->func_pointer_refcount += eind->func_pointer_refcount;
1419 eind->func_pointer_refcount = 0;
1420 }
1421
1422 _bfd_elf_link_hash_copy_indirect (info, dir, ind);
1423 }
1424}
1425
1426/* Remove undefined weak symbol from the dynamic symbol table if it
1427 is resolved to 0. */
1428
1429bfd_boolean
1430_bfd_x86_elf_fixup_symbol (struct bfd_link_info *info,
1431 struct elf_link_hash_entry *h)
1432{
1433 if (h->dynindx != -1)
1434 {
1435 const struct elf_backend_data *bed
1436 = get_elf_backend_data (info->output_bfd);
1437 if (UNDEFINED_WEAK_RESOLVED_TO_ZERO (info,
1438 bed->target_id,
1439 elf_x86_hash_entry (h)->has_got_reloc,
1440 elf_x86_hash_entry (h)))
1441 {
1442 h->dynindx = -1;
1443 _bfd_elf_strtab_delref (elf_hash_table (info)->dynstr,
1444 h->dynstr_index);
1445 }
1446 }
1447 return TRUE;
1448}
1449
1450/* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */
1451
1452bfd_boolean
1453_bfd_x86_elf_hash_symbol (struct elf_link_hash_entry *h)
1454{
1455 if (h->plt.offset != (bfd_vma) -1
1456 && !h->def_regular
1457 && !h->pointer_equality_needed)
1458 return FALSE;
1459
1460 return _bfd_elf_hash_symbol (h);
1461}
1462
eeb2f20a
L
1463/* Adjust a symbol defined by a dynamic object and referenced by a
1464 regular object. The current definition is in some section of the
1465 dynamic object, but we're not including those sections. We have to
1466 change the definition to something the rest of the link can
1467 understand. */
1468
1469bfd_boolean
1470_bfd_x86_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
1471 struct elf_link_hash_entry *h)
1472{
1473 struct elf_x86_link_hash_table *htab;
1474 asection *s, *srel;
1475 struct elf_x86_link_hash_entry *eh;
1476 struct elf_dyn_relocs *p;
1477 const struct elf_backend_data *bed
1478 = get_elf_backend_data (info->output_bfd);
1479
1480 /* STT_GNU_IFUNC symbol must go through PLT. */
1481 if (h->type == STT_GNU_IFUNC)
1482 {
1483 /* All local STT_GNU_IFUNC references must be treate as local
1484 calls via local PLT. */
1485 if (h->ref_regular
1486 && SYMBOL_CALLS_LOCAL (info, h))
1487 {
1488 bfd_size_type pc_count = 0, count = 0;
1489 struct elf_dyn_relocs **pp;
1490
1491 eh = (struct elf_x86_link_hash_entry *) h;
1492 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1493 {
1494 pc_count += p->pc_count;
1495 p->count -= p->pc_count;
1496 p->pc_count = 0;
1497 count += p->count;
1498 if (p->count == 0)
1499 *pp = p->next;
1500 else
1501 pp = &p->next;
1502 }
1503
1504 if (pc_count || count)
1505 {
1506 h->non_got_ref = 1;
1507 if (pc_count)
1508 {
1509 /* Increment PLT reference count only for PC-relative
1510 references. */
1511 h->needs_plt = 1;
1512 if (h->plt.refcount <= 0)
1513 h->plt.refcount = 1;
1514 else
1515 h->plt.refcount += 1;
1516 }
1517 }
1518 }
1519
1520 if (h->plt.refcount <= 0)
1521 {
1522 h->plt.offset = (bfd_vma) -1;
1523 h->needs_plt = 0;
1524 }
1525 return TRUE;
1526 }
1527
1528 /* If this is a function, put it in the procedure linkage table. We
1529 will fill in the contents of the procedure linkage table later,
1530 when we know the address of the .got section. */
1531 if (h->type == STT_FUNC
1532 || h->needs_plt)
1533 {
1534 if (h->plt.refcount <= 0
1535 || SYMBOL_CALLS_LOCAL (info, h)
1536 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1537 && h->root.type == bfd_link_hash_undefweak))
1538 {
1539 /* This case can occur if we saw a PLT32 reloc in an input
1540 file, but the symbol was never referred to by a dynamic
1541 object, or if all references were garbage collected. In
1542 such a case, we don't actually need to build a procedure
1543 linkage table, and we can just do a PC32 reloc instead. */
1544 h->plt.offset = (bfd_vma) -1;
1545 h->needs_plt = 0;
1546 }
1547
1548 return TRUE;
1549 }
1550 else
1551 /* It's possible that we incorrectly decided a .plt reloc was needed
1552 * for an R_386_PC32/R_X86_64_PC32 reloc to a non-function sym in
1553 check_relocs. We can't decide accurately between function and
1554 non-function syms in check-relocs; Objects loaded later in
1555 the link may change h->type. So fix it now. */
1556 h->plt.offset = (bfd_vma) -1;
1557
1558 eh = (struct elf_x86_link_hash_entry *) h;
1559
1560 /* If this is a weak symbol, and there is a real definition, the
1561 processor independent code will have arranged for us to see the
1562 real definition first, and we can just use the same value. */
1563 if (h->u.weakdef != NULL)
1564 {
1565 BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined
1566 || h->u.weakdef->root.type == bfd_link_hash_defweak);
1567 h->root.u.def.section = h->u.weakdef->root.u.def.section;
1568 h->root.u.def.value = h->u.weakdef->root.u.def.value;
1569 if (ELIMINATE_COPY_RELOCS
1570 || info->nocopyreloc
1571 || SYMBOL_NO_COPYRELOC (info, eh))
1572 {
1573 /* NB: needs_copy is always 0 for i386. */
1574 h->non_got_ref = h->u.weakdef->non_got_ref;
1575 eh->needs_copy = h->u.weakdef->needs_copy;
1576 }
1577 return TRUE;
1578 }
1579
1580 /* This is a reference to a symbol defined by a dynamic object which
1581 is not a function. */
1582
1583 /* If we are creating a shared library, we must presume that the
1584 only references to the symbol are via the global offset table.
1585 For such cases we need not do anything here; the relocations will
1586 be handled correctly by relocate_section. */
1587 if (!bfd_link_executable (info))
1588 return TRUE;
1589
1590 /* If there are no references to this symbol that do not use the
1591 GOT nor R_386_GOTOFF relocation, we don't need to generate a copy
1592 reloc. NB: gotoff_ref is always 0 for x86-64. */
1593 if (!h->non_got_ref && !eh->gotoff_ref)
1594 return TRUE;
1595
1596 /* If -z nocopyreloc was given, we won't generate them either. */
1597 if (info->nocopyreloc || SYMBOL_NO_COPYRELOC (info, eh))
1598 {
1599 h->non_got_ref = 0;
1600 return TRUE;
1601 }
1602
1603 htab = elf_x86_hash_table (info, bed->target_id);
1604 if (htab == NULL)
1605 return FALSE;
1606
1607 /* If there aren't any dynamic relocs in read-only sections nor
1608 R_386_GOTOFF relocation, then we can keep the dynamic relocs and
1609 avoid the copy reloc. This doesn't work on VxWorks, where we can
1610 not have dynamic relocations (other than copy and jump slot
1611 relocations) in an executable. */
1612 if (ELIMINATE_COPY_RELOCS
1613 && (bed->target_id == X86_64_ELF_DATA
1614 || (!eh->gotoff_ref
1615 && !htab->is_vxworks)))
1616 {
1617 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1618 {
1619 s = p->sec->output_section;
1620 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1621 break;
1622 }
1623
1624 /* If we didn't find any dynamic relocs in read-only sections,
1625 then we'll be keeping the dynamic relocs and avoiding the copy
1626 reloc. */
1627 if (p == NULL)
1628 {
1629 h->non_got_ref = 0;
1630 return TRUE;
1631 }
1632 }
1633
1634 /* We must allocate the symbol in our .dynbss section, which will
1635 become part of the .bss section of the executable. There will be
1636 an entry for this symbol in the .dynsym section. The dynamic
1637 object will contain position independent code, so all references
1638 from the dynamic object to this symbol will go through the global
1639 offset table. The dynamic linker will use the .dynsym entry to
1640 determine the address it must put in the global offset table, so
1641 both the dynamic object and the regular object will refer to the
1642 same memory location for the variable. */
1643
1644 /* We must generate a R_386_COPY/R_X86_64_COPY reloc to tell the
1645 dynamic linker to copy the initial value out of the dynamic object
1646 and into the runtime process image. */
1647 if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
1648 {
1649 s = htab->elf.sdynrelro;
1650 srel = htab->elf.sreldynrelro;
1651 }
1652 else
1653 {
1654 s = htab->elf.sdynbss;
1655 srel = htab->elf.srelbss;
1656 }
1657 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
1658 {
503294e7 1659 srel->size += htab->sizeof_reloc;
eeb2f20a
L
1660 h->needs_copy = 1;
1661 }
1662
1663 return _bfd_elf_adjust_dynamic_copy (info, h, s);
1664}
1665
6999821f
L
1666/* Return TRUE if a symbol is referenced locally. It is similar to
1667 SYMBOL_REFERENCES_LOCAL, but it also checks version script. It
1668 works in check_relocs. */
1669
1670bfd_boolean
1671_bfd_x86_elf_link_symbol_references_local (struct bfd_link_info *info,
1672 struct elf_link_hash_entry *h)
1673{
1674 struct elf_x86_link_hash_entry *eh
1675 = (struct elf_x86_link_hash_entry *) h;
1676
1677 if (eh->local_ref > 1)
1678 return TRUE;
1679
1680 if (eh->local_ref == 1)
1681 return FALSE;
1682
1683 /* Unversioned symbols defined in regular objects can be forced local
1684 by linker version script. A weak undefined symbol can fored local
1685 if it has non-default visibility or "-z nodynamic-undefined-weak"
1686 is used. */
1687 if (SYMBOL_REFERENCES_LOCAL (info, h)
1688 || ((ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1689 || info->dynamic_undefined_weak == 0)
1690 && h->root.type == bfd_link_hash_undefweak)
1691 || ((h->def_regular || ELF_COMMON_DEF_P (h))
1692 && h->versioned == unversioned
1693 && info->version_info != NULL
1694 && bfd_hide_sym_by_version (info->version_info,
1695 h->root.root.string)))
1696 {
1697 eh->local_ref = 2;
1698 return TRUE;
1699 }
1700
1701 eh->local_ref = 1;
1702 return FALSE;
1703}
1704
4f501a24
L
1705/* Return the section that should be marked against GC for a given
1706 relocation. */
1707
1708asection *
1709_bfd_x86_elf_gc_mark_hook (asection *sec,
1710 struct bfd_link_info *info,
1711 Elf_Internal_Rela *rel,
1712 struct elf_link_hash_entry *h,
1713 Elf_Internal_Sym *sym)
1714{
1715 /* Compiler should optimize this out. */
1716 if (((unsigned int) R_X86_64_GNU_VTINHERIT
1717 != (unsigned int) R_386_GNU_VTINHERIT)
1718 || ((unsigned int) R_X86_64_GNU_VTENTRY
1719 != (unsigned int) R_386_GNU_VTENTRY))
1720 abort ();
1721
1722 if (h != NULL)
1723 switch (ELF32_R_TYPE (rel->r_info))
1724 {
1725 case R_X86_64_GNU_VTINHERIT:
1726 case R_X86_64_GNU_VTENTRY:
1727 return NULL;
1728 }
1729
1730 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
1731}
1732
f493882d
L
1733static bfd_vma
1734elf_i386_get_plt_got_vma (struct elf_x86_plt *plt_p ATTRIBUTE_UNUSED,
1735 bfd_vma off,
1736 bfd_vma offset ATTRIBUTE_UNUSED,
1737 bfd_vma got_addr)
1738{
1739 return got_addr + off;
1740}
1741
1742static bfd_vma
1743elf_x86_64_get_plt_got_vma (struct elf_x86_plt *plt_p,
1744 bfd_vma off,
1745 bfd_vma offset,
1746 bfd_vma got_addr ATTRIBUTE_UNUSED)
1747{
1748 return plt_p->sec->vma + offset + off + plt_p->plt_got_insn_size;
1749}
1750
1751static bfd_boolean
1752elf_i386_valid_plt_reloc_p (unsigned int type)
1753{
1754 return (type == R_386_JUMP_SLOT
1755 || type == R_386_GLOB_DAT
1756 || type == R_386_IRELATIVE);
1757}
1758
1759static bfd_boolean
1760elf_x86_64_valid_plt_reloc_p (unsigned int type)
1761{
1762 return (type == R_X86_64_JUMP_SLOT
1763 || type == R_X86_64_GLOB_DAT
1764 || type == R_X86_64_IRELATIVE);
1765}
1766
1767long
1768_bfd_x86_elf_get_synthetic_symtab (bfd *abfd,
1769 long count,
1770 long relsize,
1771 bfd_vma got_addr,
1772 struct elf_x86_plt plts[],
1773 asymbol **dynsyms,
1774 asymbol **ret)
1775{
1776 long size, i, n, len;
1777 int j;
1778 unsigned int plt_got_offset, plt_entry_size;
1779 asymbol *s;
1780 bfd_byte *plt_contents;
1781 long dynrelcount;
1782 arelent **dynrelbuf, *p;
1783 char *names;
1784 const struct elf_backend_data *bed;
1785 bfd_vma (*get_plt_got_vma) (struct elf_x86_plt *, bfd_vma, bfd_vma,
1786 bfd_vma);
1787 bfd_boolean (*valid_plt_reloc_p) (unsigned int);
1788
1789 if (count == 0)
1790 return -1;
1791
1792 dynrelbuf = (arelent **) bfd_malloc (relsize);
1793 if (dynrelbuf == NULL)
1794 return -1;
1795
1796 dynrelcount = bfd_canonicalize_dynamic_reloc (abfd, dynrelbuf,
1797 dynsyms);
1798
1799 /* Sort the relocs by address. */
1800 qsort (dynrelbuf, dynrelcount, sizeof (arelent *),
1801 _bfd_x86_elf_compare_relocs);
1802
1803 size = count * sizeof (asymbol);
1804
1805 /* Allocate space for @plt suffixes. */
1806 n = 0;
1807 for (i = 0; i < dynrelcount; i++)
1808 {
1809 p = dynrelbuf[i];
1810 size += strlen ((*p->sym_ptr_ptr)->name) + sizeof ("@plt");
1811 if (p->addend != 0)
1812 size += sizeof ("+0x") - 1 + 8 + 8 * ABI_64_P (abfd);
1813 }
1814
1815 s = *ret = (asymbol *) bfd_zmalloc (size);
1816 if (s == NULL)
1817 goto bad_return;
1818
1819 bed = get_elf_backend_data (abfd);
1820
1821 if (bed->target_id == X86_64_ELF_DATA)
1822 {
1823 get_plt_got_vma = elf_x86_64_get_plt_got_vma;
1824 valid_plt_reloc_p = elf_x86_64_valid_plt_reloc_p;
1825 }
1826 else
1827 {
1828 get_plt_got_vma = elf_i386_get_plt_got_vma;
1829 valid_plt_reloc_p = elf_i386_valid_plt_reloc_p;
1830 if (got_addr)
1831 {
1832 /* Check .got.plt and then .got to get the _GLOBAL_OFFSET_TABLE_
1833 address. */
1834 asection *sec = bfd_get_section_by_name (abfd, ".got.plt");
1835 if (sec != NULL)
1836 got_addr = sec->vma;
1837 else
1838 {
1839 sec = bfd_get_section_by_name (abfd, ".got");
1840 if (sec != NULL)
1841 got_addr = sec->vma;
1842 }
1843
1844 if (got_addr == (bfd_vma) -1)
1845 goto bad_return;
1846 }
1847 }
1848
1849 /* Check for each PLT section. */
1850 names = (char *) (s + count);
1851 size = 0;
1852 n = 0;
1853 for (j = 0; plts[j].name != NULL; j++)
1854 if ((plt_contents = plts[j].contents) != NULL)
1855 {
1856 long k;
1857 bfd_vma offset;
1858 asection *plt;
1859 struct elf_x86_plt *plt_p = &plts[j];
1860
1861 plt_got_offset = plt_p->plt_got_offset;
1862 plt_entry_size = plt_p->plt_entry_size;
1863
1864 plt = plt_p->sec;
1865
1866 if ((plt_p->type & plt_lazy))
1867 {
1868 /* Skip PLT0 in lazy PLT. */
1869 k = 1;
1870 offset = plt_entry_size;
1871 }
1872 else
1873 {
1874 k = 0;
1875 offset = 0;
1876 }
1877
1878 /* Check each PLT entry against dynamic relocations. */
1879 for (; k < plt_p->count; k++)
1880 {
1881 int off;
1882 bfd_vma got_vma;
1883 long min, max, mid;
1884
1885 /* Get the GOT offset for i386 or the PC-relative offset
1886 for x86-64, a signed 32-bit integer. */
1887 off = H_GET_32 (abfd, (plt_contents + offset
1888 + plt_got_offset));
1889 got_vma = get_plt_got_vma (plt_p, off, offset, got_addr);
1890
1891 /* Binary search. */
1892 p = dynrelbuf[0];
1893 min = 0;
1894 max = dynrelcount;
1895 while ((min + 1) < max)
1896 {
1897 arelent *r;
1898
1899 mid = (min + max) / 2;
1900 r = dynrelbuf[mid];
1901 if (got_vma > r->address)
1902 min = mid;
1903 else if (got_vma < r->address)
1904 max = mid;
1905 else
1906 {
1907 p = r;
1908 break;
1909 }
1910 }
1911
1912 /* Skip unknown relocation. PR 17512: file: bc9d6cf5. */
1913 if (got_vma == p->address
1914 && p->howto != NULL
1915 && valid_plt_reloc_p (p->howto->type))
1916 {
1917 *s = **p->sym_ptr_ptr;
1918 /* Undefined syms won't have BSF_LOCAL or BSF_GLOBAL
1919 set. Since we are defining a symbol, ensure one
1920 of them is set. */
1921 if ((s->flags & BSF_LOCAL) == 0)
1922 s->flags |= BSF_GLOBAL;
1923 s->flags |= BSF_SYNTHETIC;
1924 /* This is no longer a section symbol. */
1925 s->flags &= ~BSF_SECTION_SYM;
1926 s->section = plt;
1927 s->the_bfd = plt->owner;
1928 s->value = offset;
1929 s->udata.p = NULL;
1930 s->name = names;
1931 len = strlen ((*p->sym_ptr_ptr)->name);
1932 memcpy (names, (*p->sym_ptr_ptr)->name, len);
1933 names += len;
1934 if (p->addend != 0)
1935 {
1936 char buf[30], *a;
1937
1938 memcpy (names, "+0x", sizeof ("+0x") - 1);
1939 names += sizeof ("+0x") - 1;
1940 bfd_sprintf_vma (abfd, buf, p->addend);
1941 for (a = buf; *a == '0'; ++a)
1942 ;
1943 size = strlen (a);
1944 memcpy (names, a, size);
1945 names += size;
1946 }
1947 memcpy (names, "@plt", sizeof ("@plt"));
1948 names += sizeof ("@plt");
1949 n++;
1950 s++;
1951 }
1952 offset += plt_entry_size;
1953 }
1954 }
1955
1956 /* PLT entries with R_386_TLS_DESC relocations are skipped. */
1957 if (n == 0)
1958 {
1959bad_return:
1960 count = -1;
1961 }
1962 else
1963 count = n;
1964
1965 for (j = 0; plts[j].name != NULL; j++)
1966 if (plts[j].contents != NULL)
1967 free (plts[j].contents);
1968
1969 free (dynrelbuf);
1970
1971 return count;
1972}
1973
0afcef53
L
1974/* Parse x86 GNU properties. */
1975
1976enum elf_property_kind
1977_bfd_x86_elf_parse_gnu_properties (bfd *abfd, unsigned int type,
1978 bfd_byte *ptr, unsigned int datasz)
1979{
1980 elf_property *prop;
1981
1982 switch (type)
1983 {
1984 case GNU_PROPERTY_X86_ISA_1_USED:
1985 case GNU_PROPERTY_X86_ISA_1_NEEDED:
1986 case GNU_PROPERTY_X86_FEATURE_1_AND:
1987 if (datasz != 4)
1988 {
1989 _bfd_error_handler
1990 ((type == GNU_PROPERTY_X86_ISA_1_USED
1991 ? _("error: %B: <corrupt x86 ISA used size: 0x%x>")
1992 : (type == GNU_PROPERTY_X86_ISA_1_NEEDED
1993 ? _("error: %B: <corrupt x86 ISA needed size: 0x%x>")
1994 : _("error: %B: <corrupt x86 feature size: 0x%x>"))),
1995 abfd, datasz);
1996 return property_corrupt;
1997 }
1998 prop = _bfd_elf_get_property (abfd, type, datasz);
1999 /* Combine properties of the same type. */
2000 prop->u.number |= bfd_h_get_32 (abfd, ptr);
2001 prop->pr_kind = property_number;
2002 break;
2003
2004 default:
2005 return property_ignored;
2006 }
2007
2008 return property_number;
2009}
2010
2011/* Merge x86 GNU property BPROP with APROP. If APROP isn't NULL,
2012 return TRUE if APROP is updated. Otherwise, return TRUE if BPROP
2013 should be merged with ABFD. */
2014
2015bfd_boolean
2016_bfd_x86_elf_merge_gnu_properties (struct bfd_link_info *info,
2017 bfd *abfd ATTRIBUTE_UNUSED,
2018 elf_property *aprop,
2019 elf_property *bprop)
2020{
2021 unsigned int number, features;
2022 bfd_boolean updated = FALSE;
2023 unsigned int pr_type = aprop != NULL ? aprop->pr_type : bprop->pr_type;
2024
2025 switch (pr_type)
2026 {
2027 case GNU_PROPERTY_X86_ISA_1_USED:
2028 case GNU_PROPERTY_X86_ISA_1_NEEDED:
2029 if (aprop != NULL && bprop != NULL)
2030 {
2031 number = aprop->u.number;
2032 aprop->u.number = number | bprop->u.number;
2033 updated = number != (unsigned int) aprop->u.number;
2034 }
2035 else
2036 {
2037 /* Return TRUE if APROP is NULL to indicate that BPROP should
2038 be added to ABFD. */
2039 updated = aprop == NULL;
2040 }
2041 break;
2042
2043 case GNU_PROPERTY_X86_FEATURE_1_AND:
2044 /* Only one of APROP and BPROP can be NULL:
2045 1. APROP & BPROP when both APROP and BPROP aren't NULL.
2046 2. If APROP is NULL, remove x86 feature.
2047 3. Otherwise, do nothing.
2048 */
2049 if (aprop != NULL && bprop != NULL)
2050 {
2051 features = 0;
2052 if (info->ibt)
2053 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2054 if (info->shstk)
2055 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2056 number = aprop->u.number;
2057 /* Add GNU_PROPERTY_X86_FEATURE_1_IBT and
2058 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2059 aprop->u.number = (number & bprop->u.number) | features;
2060 updated = number != (unsigned int) aprop->u.number;
2061 /* Remove the property if all feature bits are cleared. */
2062 if (aprop->u.number == 0)
2063 aprop->pr_kind = property_remove;
2064 }
2065 else
2066 {
2067 features = 0;
2068 if (info->ibt)
2069 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2070 if (info->shstk)
2071 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2072 if (features)
2073 {
2074 /* Add GNU_PROPERTY_X86_FEATURE_1_IBT and
2075 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2076 if (aprop != NULL)
2077 {
2078 number = aprop->u.number;
2079 aprop->u.number = number | features;
2080 updated = number != (unsigned int) aprop->u.number;
2081 }
2082 else
2083 {
2084 bprop->u.number |= features;
2085 updated = TRUE;
2086 }
2087 }
2088 else if (aprop != NULL)
2089 {
2090 aprop->pr_kind = property_remove;
2091 updated = TRUE;
2092 }
2093 }
2094 break;
2095
2096 default:
2097 /* Never should happen. */
2098 abort ();
2099 }
2100
2101 return updated;
2102}
a6798bab
L
2103
2104/* Set up x86 GNU properties. Return the first relocatable ELF input
2105 with GNU properties if found. Otherwise, return NULL. */
2106
2107bfd *
2108_bfd_x86_elf_link_setup_gnu_properties
2109 (struct bfd_link_info *info,
2110 struct elf_x86_plt_layout_table *plt_layout)
2111{
2112 bfd_boolean normal_target;
2113 bfd_boolean lazy_plt;
2114 asection *sec, *pltsec;
2115 bfd *dynobj;
2116 bfd_boolean use_ibt_plt;
2117 unsigned int plt_alignment, features;
2118 struct elf_x86_link_hash_table *htab;
2119 bfd *pbfd;
2120 bfd *ebfd = NULL;
2121 elf_property *prop;
2122 const struct elf_backend_data *bed;
2123 unsigned int class_align = ABI_64_P (info->output_bfd) ? 3 : 2;
2124 unsigned int got_align;
2125
2126 features = 0;
2127 if (info->ibt)
2128 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2129 if (info->shstk)
2130 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2131
2132 /* Find a normal input file with GNU property note. */
2133 for (pbfd = info->input_bfds;
2134 pbfd != NULL;
2135 pbfd = pbfd->link.next)
2136 if (bfd_get_flavour (pbfd) == bfd_target_elf_flavour
2137 && bfd_count_sections (pbfd) != 0)
2138 {
2139 ebfd = pbfd;
2140
2141 if (elf_properties (pbfd) != NULL)
2142 break;
2143 }
2144
2145 if (ebfd != NULL && features)
2146 {
2147 /* If features is set, add GNU_PROPERTY_X86_FEATURE_1_IBT and
2148 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2149 prop = _bfd_elf_get_property (ebfd,
2150 GNU_PROPERTY_X86_FEATURE_1_AND,
2151 4);
2152 prop->u.number |= features;
2153 prop->pr_kind = property_number;
2154
2155 /* Create the GNU property note section if needed. */
2156 if (pbfd == NULL)
2157 {
2158 sec = bfd_make_section_with_flags (ebfd,
2159 NOTE_GNU_PROPERTY_SECTION_NAME,
2160 (SEC_ALLOC
2161 | SEC_LOAD
2162 | SEC_IN_MEMORY
2163 | SEC_READONLY
2164 | SEC_HAS_CONTENTS
2165 | SEC_DATA));
2166 if (sec == NULL)
2167 info->callbacks->einfo (_("%F: failed to create GNU property section\n"));
2168
2169 if (!bfd_set_section_alignment (ebfd, sec, class_align))
2170 {
2171error_alignment:
2172 info->callbacks->einfo (_("%F%A: failed to align section\n"),
2173 sec);
2174 }
2175
2176 elf_section_type (sec) = SHT_NOTE;
2177 }
2178 }
2179
2180 pbfd = _bfd_elf_link_setup_gnu_properties (info);
2181
a6798bab
L
2182 bed = get_elf_backend_data (info->output_bfd);
2183
2184 htab = elf_x86_hash_table (info, bed->target_id);
2185 if (htab == NULL)
2186 return pbfd;
2187
eeb2f20a 2188 htab->is_vxworks = plt_layout->is_vxworks;
7a382c1c
L
2189 htab->r_info = plt_layout->r_info;
2190 htab->r_sym = plt_layout->r_sym;
2191
2192 if (bfd_link_relocatable (info))
2193 return pbfd;
eeb2f20a 2194
a6798bab
L
2195 use_ibt_plt = info->ibtplt || info->ibt;
2196 if (!use_ibt_plt && pbfd != NULL)
2197 {
2198 /* Check if GNU_PROPERTY_X86_FEATURE_1_IBT is on. */
2199 elf_property_list *p;
2200
2201 /* The property list is sorted in order of type. */
2202 for (p = elf_properties (pbfd); p; p = p->next)
2203 {
2204 if (GNU_PROPERTY_X86_FEATURE_1_AND == p->property.pr_type)
2205 {
2206 use_ibt_plt = !!(p->property.u.number
2207 & GNU_PROPERTY_X86_FEATURE_1_IBT);
2208 break;
2209 }
2210 else if (GNU_PROPERTY_X86_FEATURE_1_AND < p->property.pr_type)
2211 break;
2212 }
2213 }
2214
2215 dynobj = htab->elf.dynobj;
2216
2217 /* Set htab->elf.dynobj here so that there is no need to check and
2218 set it in check_relocs. */
2219 if (dynobj == NULL)
2220 {
2221 if (pbfd != NULL)
2222 {
2223 htab->elf.dynobj = pbfd;
2224 dynobj = pbfd;
2225 }
2226 else
2227 {
2228 bfd *abfd;
2229
2230 /* Find a normal input file to hold linker created
2231 sections. */
2232 for (abfd = info->input_bfds;
2233 abfd != NULL;
2234 abfd = abfd->link.next)
2235 if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
2236 && (abfd->flags
2237 & (DYNAMIC | BFD_LINKER_CREATED | BFD_PLUGIN)) == 0)
2238 {
2239 htab->elf.dynobj = abfd;
2240 dynobj = abfd;
2241 break;
2242 }
2243 }
2244 }
2245
2246 /* Even when lazy binding is disabled by "-z now", the PLT0 entry may
2247 still be used with LD_AUDIT or LD_PROFILE if PLT entry is used for
2248 canonical function address. */
2249 htab->plt.has_plt0 = 1;
2250 normal_target = plt_layout->normal_target;
2251
2252 if (normal_target)
2253 {
2254 if (use_ibt_plt)
2255 {
2256 htab->lazy_plt = plt_layout->lazy_ibt_plt;
2257 htab->non_lazy_plt = plt_layout->non_lazy_ibt_plt;
2258 }
2259 else
2260 {
2261 htab->lazy_plt = plt_layout->lazy_plt;
2262 htab->non_lazy_plt = plt_layout->non_lazy_plt;
2263 }
2264 }
2265 else
2266 {
2267 htab->lazy_plt = plt_layout->lazy_plt;
2268 htab->non_lazy_plt = NULL;
2269 }
2270
2271 pltsec = htab->elf.splt;
2272
2273 /* If the non-lazy PLT is available, use it for all PLT entries if
2274 there are no PLT0 or no .plt section. */
2275 if (htab->non_lazy_plt != NULL
2276 && (!htab->plt.has_plt0 || pltsec == NULL))
2277 {
2278 lazy_plt = FALSE;
2279 if (bfd_link_pic (info))
2280 htab->plt.plt_entry = htab->non_lazy_plt->pic_plt_entry;
2281 else
2282 htab->plt.plt_entry = htab->non_lazy_plt->plt_entry;
2283 htab->plt.plt_entry_size = htab->non_lazy_plt->plt_entry_size;
2284 htab->plt.plt_got_offset = htab->non_lazy_plt->plt_got_offset;
2285 htab->plt.plt_got_insn_size
2286 = htab->non_lazy_plt->plt_got_insn_size;
2287 htab->plt.eh_frame_plt_size
2288 = htab->non_lazy_plt->eh_frame_plt_size;
2289 htab->plt.eh_frame_plt = htab->non_lazy_plt->eh_frame_plt;
2290 }
2291 else
2292 {
2293 lazy_plt = TRUE;
2294 if (bfd_link_pic (info))
2295 {
2296 htab->plt.plt0_entry = htab->lazy_plt->pic_plt0_entry;
2297 htab->plt.plt_entry = htab->lazy_plt->pic_plt_entry;
2298 }
2299 else
2300 {
2301 htab->plt.plt0_entry = htab->lazy_plt->plt0_entry;
2302 htab->plt.plt_entry = htab->lazy_plt->plt_entry;
2303 }
2304 htab->plt.plt_entry_size = htab->lazy_plt->plt_entry_size;
2305 htab->plt.plt_got_offset = htab->lazy_plt->plt_got_offset;
2306 htab->plt.plt_got_insn_size
2307 = htab->lazy_plt->plt_got_insn_size;
2308 htab->plt.eh_frame_plt_size
2309 = htab->lazy_plt->eh_frame_plt_size;
2310 htab->plt.eh_frame_plt = htab->lazy_plt->eh_frame_plt;
2311 }
2312
2313 /* Return if there are no normal input files. */
2314 if (dynobj == NULL)
2315 return pbfd;
2316
eeb2f20a 2317 if (htab->is_vxworks
a6798bab
L
2318 && !elf_vxworks_create_dynamic_sections (dynobj, info,
2319 &htab->srelplt2))
2320 {
2321 info->callbacks->einfo (_("%F: failed to create VxWorks dynamic sections\n"));
2322 return pbfd;
2323 }
2324
2325 /* Since create_dynamic_sections isn't always called, but GOT
2326 relocations need GOT relocations, create them here so that we
2327 don't need to do it in check_relocs. */
2328 if (htab->elf.sgot == NULL
2329 && !_bfd_elf_create_got_section (dynobj, info))
2330 info->callbacks->einfo (_("%F: failed to create GOT sections\n"));
2331
2332 got_align = (bed->target_id == X86_64_ELF_DATA) ? 3 : 2;
2333
2334 /* Align .got and .got.plt sections to their entry size. Do it here
2335 instead of in create_dynamic_sections so that they are always
2336 properly aligned even if create_dynamic_sections isn't called. */
2337 sec = htab->elf.sgot;
2338 if (!bfd_set_section_alignment (dynobj, sec, got_align))
2339 goto error_alignment;
2340
2341 sec = htab->elf.sgotplt;
2342 if (!bfd_set_section_alignment (dynobj, sec, got_align))
2343 goto error_alignment;
2344
2345 /* Create the ifunc sections here so that check_relocs can be
2346 simplified. */
2347 if (!_bfd_elf_create_ifunc_sections (dynobj, info))
2348 info->callbacks->einfo (_("%F: failed to create ifunc sections\n"));
2349
2350 plt_alignment = bfd_log2 (htab->plt.plt_entry_size);
2351
2352 if (pltsec != NULL)
2353 {
2354 /* Whe creating executable, set the contents of the .interp
2355 section to the interpreter. */
2356 if (bfd_link_executable (info) && !info->nointerp)
2357 {
2358 asection *s = bfd_get_linker_section (dynobj, ".interp");
2359 if (s == NULL)
2360 abort ();
2361 s->size = htab->dynamic_interpreter_size;
2362 s->contents = (unsigned char *) htab->dynamic_interpreter;
2363 htab->interp = s;
2364 }
2365
2366 /* Don't change PLT section alignment for NaCl since it uses
2367 64-byte PLT entry and sets PLT section alignment to 32
2368 bytes. Don't create additional PLT sections for NaCl. */
2369 if (normal_target)
2370 {
2371 flagword pltflags = (bed->dynamic_sec_flags
2372 | SEC_ALLOC
2373 | SEC_CODE
2374 | SEC_LOAD
2375 | SEC_READONLY);
2376 unsigned int non_lazy_plt_alignment
2377 = bfd_log2 (htab->non_lazy_plt->plt_entry_size);
2378
2379 sec = pltsec;
2380 if (!bfd_set_section_alignment (sec->owner, sec,
2381 plt_alignment))
2382 goto error_alignment;
2383
2384 /* Create the GOT procedure linkage table. */
2385 sec = bfd_make_section_anyway_with_flags (dynobj,
2386 ".plt.got",
2387 pltflags);
2388 if (sec == NULL)
2389 info->callbacks->einfo (_("%F: failed to create GOT PLT section\n"));
2390
2391 if (!bfd_set_section_alignment (dynobj, sec,
2392 non_lazy_plt_alignment))
2393 goto error_alignment;
2394
2395 htab->plt_got = sec;
2396
2397 if (lazy_plt)
2398 {
2399 sec = NULL;
2400
2401 if (use_ibt_plt)
2402 {
2403 /* Create the second PLT for Intel IBT support. IBT
2404 PLT is supported only for non-NaCl target and is
2405 is needed only for lazy binding. */
2406 sec = bfd_make_section_anyway_with_flags (dynobj,
2407 ".plt.sec",
2408 pltflags);
2409 if (sec == NULL)
2410 info->callbacks->einfo (_("%F: failed to create IBT-enabled PLT section\n"));
2411
2412 if (!bfd_set_section_alignment (dynobj, sec,
2413 plt_alignment))
2414 goto error_alignment;
2415 }
2416 else if (info->bndplt && ABI_64_P (dynobj))
2417 {
2418 /* Create the second PLT for Intel MPX support. MPX
2419 PLT is supported only for non-NaCl target in 64-bit
2420 mode and is needed only for lazy binding. */
2421 sec = bfd_make_section_anyway_with_flags (dynobj,
2422 ".plt.sec",
2423 pltflags);
2424 if (sec == NULL)
2425 info->callbacks->einfo (_("%F: failed to create BND PLT section\n"));
2426
2427 if (!bfd_set_section_alignment (dynobj, sec,
2428 non_lazy_plt_alignment))
2429 goto error_alignment;
2430 }
2431
2432 htab->plt_second = sec;
2433 }
2434 }
2435
2436 if (!info->no_ld_generated_unwind_info)
2437 {
2438 flagword flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY
2439 | SEC_HAS_CONTENTS | SEC_IN_MEMORY
2440 | SEC_LINKER_CREATED);
2441
2442 sec = bfd_make_section_anyway_with_flags (dynobj,
2443 ".eh_frame",
2444 flags);
2445 if (sec == NULL)
2446 info->callbacks->einfo (_("%F: failed to create PLT .eh_frame section\n"));
2447
2448 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2449 goto error_alignment;
2450
2451 htab->plt_eh_frame = sec;
2452
2453 if (htab->plt_got != NULL)
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 GOT PLT .eh_frame section\n"));
2460
2461 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2462 goto error_alignment;
2463
2464 htab->plt_got_eh_frame = sec;
2465 }
2466
2467 if (htab->plt_second != NULL)
2468 {
2469 sec = bfd_make_section_anyway_with_flags (dynobj,
2470 ".eh_frame",
2471 flags);
2472 if (sec == NULL)
2473 info->callbacks->einfo (_("%F: failed to create the second PLT .eh_frame section\n"));
2474
2475 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2476 goto error_alignment;
2477
2478 htab->plt_second_eh_frame = sec;
2479 }
2480 }
2481 }
2482
2483 if (normal_target)
2484 {
2485 /* The .iplt section is used for IFUNC symbols in static
2486 executables. */
2487 sec = htab->elf.iplt;
2488 if (sec != NULL
2489 && !bfd_set_section_alignment (sec->owner, sec,
2490 plt_alignment))
2491 goto error_alignment;
2492 }
2493
2494 return pbfd;
2495}
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