lwp_info: Make the arch code free arch_lwp_info
[deliverable/binutils-gdb.git] / bfd / elfxx-x86.c
1 /* x86 specific support for ELF
2 Copyright (C) 2017 Free Software Foundation, Inc.
3
4 This file is part of BFD, the Binary File Descriptor library.
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
19 MA 02110-1301, USA. */
20
21 #include "elfxx-x86.h"
22 #include "elf-vxworks.h"
23 #include "objalloc.h"
24 #include "elf/i386.h"
25 #include "elf/x86-64.h"
26
27 /* The name of the dynamic interpreter. This is put in the .interp
28 section. */
29
30 #define ELF32_DYNAMIC_INTERPRETER "/usr/lib/libc.so.1"
31 #define ELF64_DYNAMIC_INTERPRETER "/lib/ld64.so.1"
32 #define ELFX32_DYNAMIC_INTERPRETER "/lib/ldx32.so.1"
33
34 bfd_boolean
35 _bfd_x86_elf_mkobject (bfd *abfd)
36 {
37 return bfd_elf_allocate_object (abfd,
38 sizeof (struct elf_x86_obj_tdata),
39 get_elf_backend_data (abfd)->target_id);
40 }
41
42 /* _TLS_MODULE_BASE_ needs to be treated especially when linking
43 executables. Rather than setting it to the beginning of the TLS
44 section, we have to set it to the end. This function may be called
45 multiple times, it is idempotent. */
46
47 void
48 _bfd_x86_elf_set_tls_module_base (struct bfd_link_info *info)
49 {
50 struct elf_x86_link_hash_table *htab;
51 struct bfd_link_hash_entry *base;
52 const struct elf_backend_data *bed;
53
54 if (!bfd_link_executable (info))
55 return;
56
57 bed = get_elf_backend_data (info->output_bfd);
58 htab = elf_x86_hash_table (info, bed->target_id);
59 if (htab == NULL)
60 return;
61
62 base = htab->tls_module_base;
63 if (base == NULL)
64 return;
65
66 base->u.def.value = htab->elf.tls_size;
67 }
68
69 /* Return the base VMA address which should be subtracted from real addresses
70 when resolving @dtpoff relocation.
71 This is PT_TLS segment p_vaddr. */
72
73 bfd_vma
74 _bfd_x86_elf_dtpoff_base (struct bfd_link_info *info)
75 {
76 /* If tls_sec is NULL, we should have signalled an error already. */
77 if (elf_hash_table (info)->tls_sec == NULL)
78 return 0;
79 return elf_hash_table (info)->tls_sec->vma;
80 }
81
82 /* Allocate space in .plt, .got and associated reloc sections for
83 dynamic relocs. */
84
85 static bfd_boolean
86 elf_x86_allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf)
87 {
88 struct bfd_link_info *info;
89 struct elf_x86_link_hash_table *htab;
90 struct elf_x86_link_hash_entry *eh;
91 struct elf_dyn_relocs *p;
92 unsigned int plt_entry_size;
93 bfd_boolean resolved_to_zero;
94 const struct elf_backend_data *bed;
95
96 if (h->root.type == bfd_link_hash_indirect)
97 return TRUE;
98
99 eh = (struct elf_x86_link_hash_entry *) h;
100
101 info = (struct bfd_link_info *) inf;
102 bed = get_elf_backend_data (info->output_bfd);
103 htab = elf_x86_hash_table (info, bed->target_id);
104 if (htab == NULL)
105 return FALSE;
106
107 plt_entry_size = htab->plt.plt_entry_size;
108
109 resolved_to_zero = UNDEFINED_WEAK_RESOLVED_TO_ZERO (info, eh);
110
111 /* Clear the reference count of function pointer relocations if
112 symbol isn't a normal function. */
113 if (h->type != STT_FUNC)
114 eh->func_pointer_refcount = 0;
115
116 /* We can't use the GOT PLT if pointer equality is needed since
117 finish_dynamic_symbol won't clear symbol value and the dynamic
118 linker won't update the GOT slot. We will get into an infinite
119 loop at run-time. */
120 if (htab->plt_got != NULL
121 && h->type != STT_GNU_IFUNC
122 && !h->pointer_equality_needed
123 && h->plt.refcount > 0
124 && h->got.refcount > 0)
125 {
126 /* Don't use the regular PLT if there are both GOT and GOTPLT
127 reloctions. */
128 h->plt.offset = (bfd_vma) -1;
129
130 /* Use the GOT PLT. */
131 eh->plt_got.refcount = 1;
132 }
133
134 /* Since STT_GNU_IFUNC symbol must go through PLT, we handle it
135 here if it is defined and referenced in a non-shared object. */
136 if (h->type == STT_GNU_IFUNC
137 && h->def_regular)
138 {
139 if (_bfd_elf_allocate_ifunc_dyn_relocs (info, h, &eh->dyn_relocs,
140 &htab->readonly_dynrelocs_against_ifunc,
141 plt_entry_size,
142 (htab->plt.has_plt0
143 * plt_entry_size),
144 htab->got_entry_size,
145 TRUE))
146 {
147 asection *s = htab->plt_second;
148 if (h->plt.offset != (bfd_vma) -1 && s != NULL)
149 {
150 /* Use the second PLT section if it is created. */
151 eh->plt_second.offset = s->size;
152
153 /* Make room for this entry in the second PLT section. */
154 s->size += htab->non_lazy_plt->plt_entry_size;
155 }
156
157 return TRUE;
158 }
159 else
160 return FALSE;
161 }
162 /* Don't create the PLT entry if there are only function pointer
163 relocations which can be resolved at run-time. */
164 else if (htab->elf.dynamic_sections_created
165 && (h->plt.refcount > eh->func_pointer_refcount
166 || eh->plt_got.refcount > 0))
167 {
168 bfd_boolean use_plt_got = eh->plt_got.refcount > 0;
169
170 /* Clear the reference count of function pointer relocations
171 if PLT is used. */
172 eh->func_pointer_refcount = 0;
173
174 /* Make sure this symbol is output as a dynamic symbol.
175 Undefined weak syms won't yet be marked as dynamic. */
176 if (h->dynindx == -1
177 && !h->forced_local
178 && !resolved_to_zero
179 && h->root.type == bfd_link_hash_undefweak)
180 {
181 if (! bfd_elf_link_record_dynamic_symbol (info, h))
182 return FALSE;
183 }
184
185 if (bfd_link_pic (info)
186 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h))
187 {
188 asection *s = htab->elf.splt;
189 asection *second_s = htab->plt_second;
190 asection *got_s = htab->plt_got;
191
192 /* If this is the first .plt entry, make room for the special
193 first entry. The .plt section is used by prelink to undo
194 prelinking for dynamic relocations. */
195 if (s->size == 0)
196 s->size = htab->plt.has_plt0 * plt_entry_size;
197
198 if (use_plt_got)
199 eh->plt_got.offset = got_s->size;
200 else
201 {
202 h->plt.offset = s->size;
203 if (second_s)
204 eh->plt_second.offset = second_s->size;
205 }
206
207 /* If this symbol is not defined in a regular file, and we are
208 not generating a shared library, then set the symbol to this
209 location in the .plt. This is required to make function
210 pointers compare as equal between the normal executable and
211 the shared library. */
212 if (! bfd_link_pic (info)
213 && !h->def_regular)
214 {
215 if (use_plt_got)
216 {
217 /* We need to make a call to the entry of the GOT PLT
218 instead of regular PLT entry. */
219 h->root.u.def.section = got_s;
220 h->root.u.def.value = eh->plt_got.offset;
221 }
222 else
223 {
224 if (second_s)
225 {
226 /* We need to make a call to the entry of the
227 second PLT instead of regular PLT entry. */
228 h->root.u.def.section = second_s;
229 h->root.u.def.value = eh->plt_second.offset;
230 }
231 else
232 {
233 h->root.u.def.section = s;
234 h->root.u.def.value = h->plt.offset;
235 }
236 }
237 }
238
239 /* Make room for this entry. */
240 if (use_plt_got)
241 got_s->size += htab->non_lazy_plt->plt_entry_size;
242 else
243 {
244 s->size += plt_entry_size;
245 if (second_s)
246 second_s->size += htab->non_lazy_plt->plt_entry_size;
247
248 /* We also need to make an entry in the .got.plt section,
249 which will be placed in the .got section by the linker
250 script. */
251 htab->elf.sgotplt->size += htab->got_entry_size;
252
253 /* There should be no PLT relocation against resolved
254 undefined weak symbol in executable. */
255 if (!resolved_to_zero)
256 {
257 /* We also need to make an entry in the .rel.plt
258 section. */
259 htab->elf.srelplt->size += htab->sizeof_reloc;
260 htab->elf.srelplt->reloc_count++;
261 }
262 }
263
264 if (htab->is_vxworks && !bfd_link_pic (info))
265 {
266 /* VxWorks has a second set of relocations for each PLT entry
267 in executables. They go in a separate relocation section,
268 which is processed by the kernel loader. */
269
270 /* There are two relocations for the initial PLT entry: an
271 R_386_32 relocation for _GLOBAL_OFFSET_TABLE_ + 4 and an
272 R_386_32 relocation for _GLOBAL_OFFSET_TABLE_ + 8. */
273
274 asection *srelplt2 = htab->srelplt2;
275 if (h->plt.offset == plt_entry_size)
276 srelplt2->size += (htab->sizeof_reloc * 2);
277
278 /* There are two extra relocations for each subsequent PLT entry:
279 an R_386_32 relocation for the GOT entry, and an R_386_32
280 relocation for the PLT entry. */
281
282 srelplt2->size += (htab->sizeof_reloc * 2);
283 }
284 }
285 else
286 {
287 eh->plt_got.offset = (bfd_vma) -1;
288 h->plt.offset = (bfd_vma) -1;
289 h->needs_plt = 0;
290 }
291 }
292 else
293 {
294 eh->plt_got.offset = (bfd_vma) -1;
295 h->plt.offset = (bfd_vma) -1;
296 h->needs_plt = 0;
297 }
298
299 eh->tlsdesc_got = (bfd_vma) -1;
300
301 /* For i386, if R_386_TLS_{IE_32,IE,GOTIE} symbol is now local to the
302 binary, make it a R_386_TLS_LE_32 requiring no TLS entry. For
303 x86-64, if R_X86_64_GOTTPOFF symbol is now local to the binary,
304 make it a R_X86_64_TPOFF32 requiring no GOT entry. */
305 if (h->got.refcount > 0
306 && bfd_link_executable (info)
307 && h->dynindx == -1
308 && (elf_x86_hash_entry (h)->tls_type & GOT_TLS_IE))
309 h->got.offset = (bfd_vma) -1;
310 else if (h->got.refcount > 0)
311 {
312 asection *s;
313 bfd_boolean dyn;
314 int tls_type = elf_x86_hash_entry (h)->tls_type;
315
316 /* Make sure this symbol is output as a dynamic symbol.
317 Undefined weak syms won't yet be marked as dynamic. */
318 if (h->dynindx == -1
319 && !h->forced_local
320 && !resolved_to_zero
321 && h->root.type == bfd_link_hash_undefweak)
322 {
323 if (! bfd_elf_link_record_dynamic_symbol (info, h))
324 return FALSE;
325 }
326
327 s = htab->elf.sgot;
328 if (GOT_TLS_GDESC_P (tls_type))
329 {
330 eh->tlsdesc_got = htab->elf.sgotplt->size
331 - elf_x86_compute_jump_table_size (htab);
332 htab->elf.sgotplt->size += 2 * htab->got_entry_size;
333 h->got.offset = (bfd_vma) -2;
334 }
335 if (! GOT_TLS_GDESC_P (tls_type)
336 || GOT_TLS_GD_P (tls_type))
337 {
338 h->got.offset = s->size;
339 s->size += htab->got_entry_size;
340 /* R_386_TLS_GD and R_X86_64_TLSGD need 2 consecutive GOT
341 slots. */
342 if (GOT_TLS_GD_P (tls_type) || tls_type == GOT_TLS_IE_BOTH)
343 s->size += htab->got_entry_size;
344 }
345 dyn = htab->elf.dynamic_sections_created;
346 /* R_386_TLS_IE_32 needs one dynamic relocation,
347 R_386_TLS_IE resp. R_386_TLS_GOTIE needs one dynamic relocation,
348 (but if both R_386_TLS_IE_32 and R_386_TLS_IE is present, we
349 need two), R_386_TLS_GD and R_X86_64_TLSGD need one if local
350 symbol and two if global. No dynamic relocation against
351 resolved undefined weak symbol in executable. */
352 if (tls_type == GOT_TLS_IE_BOTH)
353 htab->elf.srelgot->size += 2 * htab->sizeof_reloc;
354 else if ((GOT_TLS_GD_P (tls_type) && h->dynindx == -1)
355 || (tls_type & GOT_TLS_IE))
356 htab->elf.srelgot->size += htab->sizeof_reloc;
357 else if (GOT_TLS_GD_P (tls_type))
358 htab->elf.srelgot->size += 2 * htab->sizeof_reloc;
359 else if (! GOT_TLS_GDESC_P (tls_type)
360 && ((ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
361 && !resolved_to_zero)
362 || h->root.type != bfd_link_hash_undefweak)
363 && (bfd_link_pic (info)
364 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h)))
365 htab->elf.srelgot->size += htab->sizeof_reloc;
366 if (GOT_TLS_GDESC_P (tls_type))
367 {
368 htab->elf.srelplt->size += htab->sizeof_reloc;
369 if (bed->target_id == X86_64_ELF_DATA)
370 htab->tlsdesc_plt = (bfd_vma) -1;
371 }
372 }
373 else
374 h->got.offset = (bfd_vma) -1;
375
376 if (eh->dyn_relocs == NULL)
377 return TRUE;
378
379 /* In the shared -Bsymbolic case, discard space allocated for
380 dynamic pc-relative relocs against symbols which turn out to be
381 defined in regular objects. For the normal shared case, discard
382 space for pc-relative relocs that have become local due to symbol
383 visibility changes. */
384
385 if (bfd_link_pic (info))
386 {
387 /* Relocs that use pc_count are those that appear on a call
388 insn, or certain REL relocs that can generated via assembly.
389 We want calls to protected symbols to resolve directly to the
390 function rather than going via the plt. If people want
391 function pointer comparisons to work as expected then they
392 should avoid writing weird assembly. */
393 if (SYMBOL_CALLS_LOCAL (info, h))
394 {
395 struct elf_dyn_relocs **pp;
396
397 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
398 {
399 p->count -= p->pc_count;
400 p->pc_count = 0;
401 if (p->count == 0)
402 *pp = p->next;
403 else
404 pp = &p->next;
405 }
406 }
407
408 if (htab->is_vxworks)
409 {
410 struct elf_dyn_relocs **pp;
411 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
412 {
413 if (strcmp (p->sec->output_section->name, ".tls_vars") == 0)
414 *pp = p->next;
415 else
416 pp = &p->next;
417 }
418 }
419
420 /* Also discard relocs on undefined weak syms with non-default
421 visibility or in PIE. */
422 if (eh->dyn_relocs != NULL)
423 {
424 if (h->root.type == bfd_link_hash_undefweak)
425 {
426 /* Undefined weak symbol is never bound locally in shared
427 library. */
428 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
429 || resolved_to_zero)
430 {
431 if (bed->target_id == I386_ELF_DATA
432 && h->non_got_ref)
433 {
434 /* Keep dynamic non-GOT/non-PLT relocation so
435 that we can branch to 0 without PLT. */
436 struct elf_dyn_relocs **pp;
437
438 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
439 if (p->pc_count == 0)
440 *pp = p->next;
441 else
442 {
443 /* Remove non-R_386_PC32 relocation. */
444 p->count = p->pc_count;
445 pp = &p->next;
446 }
447
448 /* Make sure undefined weak symbols are output
449 as dynamic symbols in PIEs for dynamic non-GOT
450 non-PLT reloations. */
451 if (eh->dyn_relocs != NULL
452 && !bfd_elf_link_record_dynamic_symbol (info, h))
453 return FALSE;
454 }
455 else
456 eh->dyn_relocs = NULL;
457 }
458 else if (h->dynindx == -1
459 && !h->forced_local
460 && !bfd_elf_link_record_dynamic_symbol (info, h))
461 return FALSE;
462 }
463 else if (bfd_link_executable (info)
464 && (h->needs_copy || eh->needs_copy)
465 && h->def_dynamic
466 && !h->def_regular)
467 {
468 /* NB: needs_copy is set only for x86-64. For PIE,
469 discard space for pc-relative relocs against symbols
470 which turn out to need copy relocs. */
471 struct elf_dyn_relocs **pp;
472
473 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
474 {
475 if (p->pc_count != 0)
476 *pp = p->next;
477 else
478 pp = &p->next;
479 }
480 }
481 }
482 }
483 else if (ELIMINATE_COPY_RELOCS)
484 {
485 /* For the non-shared case, discard space for relocs against
486 symbols which turn out to need copy relocs or are not
487 dynamic. Keep dynamic relocations for run-time function
488 pointer initialization. */
489
490 if ((!h->non_got_ref
491 || eh->func_pointer_refcount > 0
492 || (h->root.type == bfd_link_hash_undefweak
493 && !resolved_to_zero))
494 && ((h->def_dynamic
495 && !h->def_regular)
496 || (htab->elf.dynamic_sections_created
497 && (h->root.type == bfd_link_hash_undefweak
498 || h->root.type == bfd_link_hash_undefined))))
499 {
500 /* Make sure this symbol is output as a dynamic symbol.
501 Undefined weak syms won't yet be marked as dynamic. */
502 if (h->dynindx == -1
503 && !h->forced_local
504 && !resolved_to_zero
505 && h->root.type == bfd_link_hash_undefweak
506 && ! bfd_elf_link_record_dynamic_symbol (info, h))
507 return FALSE;
508
509 /* If that succeeded, we know we'll be keeping all the
510 relocs. */
511 if (h->dynindx != -1)
512 goto keep;
513 }
514
515 eh->dyn_relocs = NULL;
516 eh->func_pointer_refcount = 0;
517
518 keep: ;
519 }
520
521 /* Finally, allocate space. */
522 for (p = eh->dyn_relocs; p != NULL; p = p->next)
523 {
524 asection *sreloc;
525
526 sreloc = elf_section_data (p->sec)->sreloc;
527
528 BFD_ASSERT (sreloc != NULL);
529 sreloc->size += p->count * htab->sizeof_reloc;
530 }
531
532 return TRUE;
533 }
534
535 /* Find any dynamic relocs that apply to read-only sections. */
536
537 bfd_boolean
538 _bfd_x86_elf_readonly_dynrelocs (struct elf_link_hash_entry *h,
539 void *inf)
540 {
541 struct elf_x86_link_hash_entry *eh;
542 struct elf_dyn_relocs *p;
543
544 /* Skip local IFUNC symbols. */
545 if (h->forced_local && h->type == STT_GNU_IFUNC)
546 return TRUE;
547
548 eh = (struct elf_x86_link_hash_entry *) h;
549 for (p = eh->dyn_relocs; p != NULL; p = p->next)
550 {
551 asection *s = p->sec->output_section;
552
553 if (s != NULL && (s->flags & SEC_READONLY) != 0)
554 {
555 struct bfd_link_info *info = (struct bfd_link_info *) inf;
556
557 info->flags |= DF_TEXTREL;
558
559 if ((info->warn_shared_textrel && bfd_link_pic (info))
560 || info->error_textrel)
561 /* xgettext:c-format */
562 info->callbacks->einfo (_("%P: %B: warning: relocation against `%s' in readonly section `%A'\n"),
563 p->sec->owner, h->root.root.string,
564 p->sec);
565
566 /* Not an error, just cut short the traversal. */
567 return FALSE;
568 }
569 }
570 return TRUE;
571 }
572
573 /* Allocate space in .plt, .got and associated reloc sections for
574 local dynamic relocs. */
575
576 static bfd_boolean
577 elf_x86_allocate_local_dynreloc (void **slot, void *inf)
578 {
579 struct elf_link_hash_entry *h
580 = (struct elf_link_hash_entry *) *slot;
581
582 if (h->type != STT_GNU_IFUNC
583 || !h->def_regular
584 || !h->ref_regular
585 || !h->forced_local
586 || h->root.type != bfd_link_hash_defined)
587 abort ();
588
589 return elf_x86_allocate_dynrelocs (h, inf);
590 }
591
592 /* Find and/or create a hash entry for local symbol. */
593
594 struct elf_link_hash_entry *
595 _bfd_elf_x86_get_local_sym_hash (struct elf_x86_link_hash_table *htab,
596 bfd *abfd, const Elf_Internal_Rela *rel,
597 bfd_boolean create)
598 {
599 struct elf_x86_link_hash_entry e, *ret;
600 asection *sec = abfd->sections;
601 hashval_t h = ELF_LOCAL_SYMBOL_HASH (sec->id,
602 htab->r_sym (rel->r_info));
603 void **slot;
604
605 e.elf.indx = sec->id;
606 e.elf.dynstr_index = htab->r_sym (rel->r_info);
607 slot = htab_find_slot_with_hash (htab->loc_hash_table, &e, h,
608 create ? INSERT : NO_INSERT);
609
610 if (!slot)
611 return NULL;
612
613 if (*slot)
614 {
615 ret = (struct elf_x86_link_hash_entry *) *slot;
616 return &ret->elf;
617 }
618
619 ret = (struct elf_x86_link_hash_entry *)
620 objalloc_alloc ((struct objalloc *) htab->loc_hash_memory,
621 sizeof (struct elf_x86_link_hash_entry));
622 if (ret)
623 {
624 memset (ret, 0, sizeof (*ret));
625 ret->elf.indx = sec->id;
626 ret->elf.dynstr_index = htab->r_sym (rel->r_info);
627 ret->elf.dynindx = -1;
628 ret->plt_got.offset = (bfd_vma) -1;
629 *slot = ret;
630 }
631 return &ret->elf;
632 }
633
634 /* Create an entry in a x86 ELF linker hash table. NB: THIS MUST BE IN
635 SYNC WITH _bfd_elf_link_hash_newfunc. */
636
637 struct bfd_hash_entry *
638 _bfd_x86_elf_link_hash_newfunc (struct bfd_hash_entry *entry,
639 struct bfd_hash_table *table,
640 const char *string)
641 {
642 /* Allocate the structure if it has not already been allocated by a
643 subclass. */
644 if (entry == NULL)
645 {
646 entry = (struct bfd_hash_entry *)
647 bfd_hash_allocate (table,
648 sizeof (struct elf_x86_link_hash_entry));
649 if (entry == NULL)
650 return entry;
651 }
652
653 /* Call the allocation method of the superclass. */
654 entry = _bfd_link_hash_newfunc (entry, table, string);
655 if (entry != NULL)
656 {
657 struct elf_x86_link_hash_entry *eh
658 = (struct elf_x86_link_hash_entry *) entry;
659 struct elf_link_hash_table *htab
660 = (struct elf_link_hash_table *) table;
661
662 memset (&eh->elf.size, 0,
663 (sizeof (struct elf_x86_link_hash_entry)
664 - offsetof (struct elf_link_hash_entry, size)));
665 /* Set local fields. */
666 eh->elf.indx = -1;
667 eh->elf.dynindx = -1;
668 eh->elf.got = htab->init_got_refcount;
669 eh->elf.plt = htab->init_plt_refcount;
670 /* Assume that we have been called by a non-ELF symbol reader.
671 This flag is then reset by the code which reads an ELF input
672 file. This ensures that a symbol created by a non-ELF symbol
673 reader will have the flag set correctly. */
674 eh->elf.non_elf = 1;
675 eh->plt_second.offset = (bfd_vma) -1;
676 eh->plt_got.offset = (bfd_vma) -1;
677 eh->tlsdesc_got = (bfd_vma) -1;
678 eh->zero_undefweak = 1;
679 }
680
681 return entry;
682 }
683
684 /* Compute a hash of a local hash entry. We use elf_link_hash_entry
685 for local symbol so that we can handle local STT_GNU_IFUNC symbols
686 as global symbol. We reuse indx and dynstr_index for local symbol
687 hash since they aren't used by global symbols in this backend. */
688
689 hashval_t
690 _bfd_x86_elf_local_htab_hash (const void *ptr)
691 {
692 struct elf_link_hash_entry *h
693 = (struct elf_link_hash_entry *) ptr;
694 return ELF_LOCAL_SYMBOL_HASH (h->indx, h->dynstr_index);
695 }
696
697 /* Compare local hash entries. */
698
699 int
700 _bfd_x86_elf_local_htab_eq (const void *ptr1, const void *ptr2)
701 {
702 struct elf_link_hash_entry *h1
703 = (struct elf_link_hash_entry *) ptr1;
704 struct elf_link_hash_entry *h2
705 = (struct elf_link_hash_entry *) ptr2;
706
707 return h1->indx == h2->indx && h1->dynstr_index == h2->dynstr_index;
708 }
709
710 /* Destroy an x86 ELF linker hash table. */
711
712 static void
713 elf_x86_link_hash_table_free (bfd *obfd)
714 {
715 struct elf_x86_link_hash_table *htab
716 = (struct elf_x86_link_hash_table *) obfd->link.hash;
717
718 if (htab->loc_hash_table)
719 htab_delete (htab->loc_hash_table);
720 if (htab->loc_hash_memory)
721 objalloc_free ((struct objalloc *) htab->loc_hash_memory);
722 _bfd_elf_link_hash_table_free (obfd);
723 }
724
725 static bfd_boolean
726 elf_i386_is_reloc_section (const char *secname)
727 {
728 return CONST_STRNEQ (secname, ".rel");
729 }
730
731 static bfd_boolean
732 elf_x86_64_is_reloc_section (const char *secname)
733 {
734 return CONST_STRNEQ (secname, ".rela");
735 }
736
737 /* Create an x86 ELF linker hash table. */
738
739 struct bfd_link_hash_table *
740 _bfd_x86_elf_link_hash_table_create (bfd *abfd)
741 {
742 struct elf_x86_link_hash_table *ret;
743 const struct elf_backend_data *bed;
744 bfd_size_type amt = sizeof (struct elf_x86_link_hash_table);
745
746 ret = (struct elf_x86_link_hash_table *) bfd_zmalloc (amt);
747 if (ret == NULL)
748 return NULL;
749
750 bed = get_elf_backend_data (abfd);
751 if (!_bfd_elf_link_hash_table_init (&ret->elf, abfd,
752 _bfd_x86_elf_link_hash_newfunc,
753 sizeof (struct elf_x86_link_hash_entry),
754 bed->target_id))
755 {
756 free (ret);
757 return NULL;
758 }
759
760 if (bed->target_id == X86_64_ELF_DATA)
761 {
762 ret->is_reloc_section = elf_x86_64_is_reloc_section;
763 ret->dt_reloc = DT_RELA;
764 ret->dt_reloc_sz = DT_RELASZ;
765 ret->dt_reloc_ent = DT_RELAENT;
766 ret->got_entry_size = 8;
767 ret->tls_get_addr = "__tls_get_addr";
768 }
769 if (ABI_64_P (abfd))
770 {
771 ret->sizeof_reloc = sizeof (Elf64_External_Rela);
772 ret->pointer_r_type = R_X86_64_64;
773 ret->dynamic_interpreter = ELF64_DYNAMIC_INTERPRETER;
774 ret->dynamic_interpreter_size = sizeof ELF64_DYNAMIC_INTERPRETER;
775 }
776 else
777 {
778 if (bed->target_id == X86_64_ELF_DATA)
779 {
780 ret->sizeof_reloc = sizeof (Elf32_External_Rela);
781 ret->pointer_r_type = R_X86_64_32;
782 ret->dynamic_interpreter = ELFX32_DYNAMIC_INTERPRETER;
783 ret->dynamic_interpreter_size
784 = sizeof ELFX32_DYNAMIC_INTERPRETER;
785 }
786 else
787 {
788 ret->is_reloc_section = elf_i386_is_reloc_section;
789 ret->dt_reloc = DT_REL;
790 ret->dt_reloc_sz = DT_RELSZ;
791 ret->dt_reloc_ent = DT_RELENT;
792 ret->sizeof_reloc = sizeof (Elf32_External_Rel);
793 ret->got_entry_size = 4;
794 ret->pointer_r_type = R_386_32;
795 ret->dynamic_interpreter = ELF32_DYNAMIC_INTERPRETER;
796 ret->dynamic_interpreter_size
797 = sizeof ELF32_DYNAMIC_INTERPRETER;
798 ret->tls_get_addr = "___tls_get_addr";
799 }
800 }
801 ret->target_id = bed->target_id;
802
803 ret->loc_hash_table = htab_try_create (1024,
804 _bfd_x86_elf_local_htab_hash,
805 _bfd_x86_elf_local_htab_eq,
806 NULL);
807 ret->loc_hash_memory = objalloc_create ();
808 if (!ret->loc_hash_table || !ret->loc_hash_memory)
809 {
810 elf_x86_link_hash_table_free (abfd);
811 return NULL;
812 }
813 ret->elf.root.hash_table_free = elf_x86_link_hash_table_free;
814
815 return &ret->elf.root;
816 }
817
818 /* Sort relocs into address order. */
819
820 int
821 _bfd_x86_elf_compare_relocs (const void *ap, const void *bp)
822 {
823 const arelent *a = * (const arelent **) ap;
824 const arelent *b = * (const arelent **) bp;
825
826 if (a->address > b->address)
827 return 1;
828 else if (a->address < b->address)
829 return -1;
830 else
831 return 0;
832 }
833
834 bfd_boolean
835 _bfd_x86_elf_link_check_relocs (bfd *abfd, struct bfd_link_info *info)
836 {
837 if (!bfd_link_relocatable (info))
838 {
839 /* Check for __tls_get_addr reference. */
840 struct elf_x86_link_hash_table *htab;
841 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
842 htab = elf_x86_hash_table (info, bed->target_id);
843 if (htab)
844 {
845 struct elf_link_hash_entry *h;
846
847 h = elf_link_hash_lookup (elf_hash_table (info),
848 htab->tls_get_addr,
849 FALSE, FALSE, FALSE);
850 if (h != NULL)
851 elf_x86_hash_entry (h)->tls_get_addr = 1;
852
853 /* "__ehdr_start" will be defined by linker as a hidden symbol
854 later if it is referenced and not defined. */
855 h = elf_link_hash_lookup (elf_hash_table (info),
856 "__ehdr_start",
857 FALSE, FALSE, FALSE);
858 if (h != NULL
859 && (h->root.type == bfd_link_hash_new
860 || h->root.type == bfd_link_hash_undefined
861 || h->root.type == bfd_link_hash_undefweak
862 || h->root.type == bfd_link_hash_common))
863 {
864 elf_x86_hash_entry (h)->local_ref = 2;
865 elf_x86_hash_entry (h)->linker_def = 1;
866 }
867 }
868 }
869
870 /* Invoke the regular ELF backend linker to do all the work. */
871 return _bfd_elf_link_check_relocs (abfd, info);
872 }
873
874 /* Set the sizes of the dynamic sections. */
875
876 bfd_boolean
877 _bfd_x86_elf_size_dynamic_sections (bfd *output_bfd,
878 struct bfd_link_info *info)
879 {
880 struct elf_x86_link_hash_table *htab;
881 bfd *dynobj;
882 asection *s;
883 bfd_boolean relocs;
884 bfd *ibfd;
885 const struct elf_backend_data *bed
886 = get_elf_backend_data (output_bfd);
887
888 htab = elf_x86_hash_table (info, bed->target_id);
889 if (htab == NULL)
890 return FALSE;
891 dynobj = htab->elf.dynobj;
892 if (dynobj == NULL)
893 abort ();
894
895 /* Set up .got offsets for local syms, and space for local dynamic
896 relocs. */
897 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
898 {
899 bfd_signed_vma *local_got;
900 bfd_signed_vma *end_local_got;
901 char *local_tls_type;
902 bfd_vma *local_tlsdesc_gotent;
903 bfd_size_type locsymcount;
904 Elf_Internal_Shdr *symtab_hdr;
905 asection *srel;
906
907 if (! is_x86_elf (ibfd, htab))
908 continue;
909
910 for (s = ibfd->sections; s != NULL; s = s->next)
911 {
912 struct elf_dyn_relocs *p;
913
914 for (p = ((struct elf_dyn_relocs *)
915 elf_section_data (s)->local_dynrel);
916 p != NULL;
917 p = p->next)
918 {
919 if (!bfd_is_abs_section (p->sec)
920 && bfd_is_abs_section (p->sec->output_section))
921 {
922 /* Input section has been discarded, either because
923 it is a copy of a linkonce section or due to
924 linker script /DISCARD/, so we'll be discarding
925 the relocs too. */
926 }
927 else if (htab->is_vxworks
928 && strcmp (p->sec->output_section->name,
929 ".tls_vars") == 0)
930 {
931 /* Relocations in vxworks .tls_vars sections are
932 handled specially by the loader. */
933 }
934 else if (p->count != 0)
935 {
936 srel = elf_section_data (p->sec)->sreloc;
937 srel->size += p->count * htab->sizeof_reloc;
938 if ((p->sec->output_section->flags & SEC_READONLY) != 0
939 && (info->flags & DF_TEXTREL) == 0)
940 {
941 info->flags |= DF_TEXTREL;
942 if ((info->warn_shared_textrel && bfd_link_pic (info))
943 || info->error_textrel)
944 /* xgettext:c-format */
945 info->callbacks->einfo (_("%P: %B: warning: relocation in readonly section `%A'\n"),
946 p->sec->owner, p->sec);
947 }
948 }
949 }
950 }
951
952 local_got = elf_local_got_refcounts (ibfd);
953 if (!local_got)
954 continue;
955
956 symtab_hdr = &elf_symtab_hdr (ibfd);
957 locsymcount = symtab_hdr->sh_info;
958 end_local_got = local_got + locsymcount;
959 local_tls_type = elf_x86_local_got_tls_type (ibfd);
960 local_tlsdesc_gotent = elf_x86_local_tlsdesc_gotent (ibfd);
961 s = htab->elf.sgot;
962 srel = htab->elf.srelgot;
963 for (; local_got < end_local_got;
964 ++local_got, ++local_tls_type, ++local_tlsdesc_gotent)
965 {
966 *local_tlsdesc_gotent = (bfd_vma) -1;
967 if (*local_got > 0)
968 {
969 if (GOT_TLS_GDESC_P (*local_tls_type))
970 {
971 *local_tlsdesc_gotent = htab->elf.sgotplt->size
972 - elf_x86_compute_jump_table_size (htab);
973 htab->elf.sgotplt->size += 2 * htab->got_entry_size;
974 *local_got = (bfd_vma) -2;
975 }
976 if (! GOT_TLS_GDESC_P (*local_tls_type)
977 || GOT_TLS_GD_P (*local_tls_type))
978 {
979 *local_got = s->size;
980 s->size += htab->got_entry_size;
981 if (GOT_TLS_GD_P (*local_tls_type)
982 || *local_tls_type == GOT_TLS_IE_BOTH)
983 s->size += htab->got_entry_size;
984 }
985 if (bfd_link_pic (info)
986 || GOT_TLS_GD_ANY_P (*local_tls_type)
987 || (*local_tls_type & GOT_TLS_IE))
988 {
989 if (*local_tls_type == GOT_TLS_IE_BOTH)
990 srel->size += 2 * htab->sizeof_reloc;
991 else if (GOT_TLS_GD_P (*local_tls_type)
992 || ! GOT_TLS_GDESC_P (*local_tls_type))
993 srel->size += htab->sizeof_reloc;
994 if (GOT_TLS_GDESC_P (*local_tls_type))
995 {
996 htab->elf.srelplt->size += htab->sizeof_reloc;
997 if (bed->target_id == X86_64_ELF_DATA)
998 htab->tlsdesc_plt = (bfd_vma) -1;
999 }
1000 }
1001 }
1002 else
1003 *local_got = (bfd_vma) -1;
1004 }
1005 }
1006
1007 if (htab->tls_ld_or_ldm_got.refcount > 0)
1008 {
1009 /* Allocate 2 got entries and 1 dynamic reloc for R_386_TLS_LDM
1010 or R_X86_64_TLSLD relocs. */
1011 htab->tls_ld_or_ldm_got.offset = htab->elf.sgot->size;
1012 htab->elf.sgot->size += 2 * htab->got_entry_size;
1013 htab->elf.srelgot->size += htab->sizeof_reloc;
1014 }
1015 else
1016 htab->tls_ld_or_ldm_got.offset = -1;
1017
1018 /* Allocate global sym .plt and .got entries, and space for global
1019 sym dynamic relocs. */
1020 elf_link_hash_traverse (&htab->elf, elf_x86_allocate_dynrelocs,
1021 info);
1022
1023 /* Allocate .plt and .got entries, and space for local symbols. */
1024 htab_traverse (htab->loc_hash_table, elf_x86_allocate_local_dynreloc,
1025 info);
1026
1027 /* For every jump slot reserved in the sgotplt, reloc_count is
1028 incremented. However, when we reserve space for TLS descriptors,
1029 it's not incremented, so in order to compute the space reserved
1030 for them, it suffices to multiply the reloc count by the jump
1031 slot size.
1032
1033 PR ld/13302: We start next_irelative_index at the end of .rela.plt
1034 so that R_{386,X86_64}_IRELATIVE entries come last. */
1035 if (htab->elf.srelplt)
1036 {
1037 htab->next_tls_desc_index = htab->elf.srelplt->reloc_count;
1038 htab->sgotplt_jump_table_size
1039 = elf_x86_compute_jump_table_size (htab);
1040 htab->next_irelative_index = htab->elf.srelplt->reloc_count - 1;
1041 }
1042 else if (htab->elf.irelplt)
1043 htab->next_irelative_index = htab->elf.irelplt->reloc_count - 1;
1044
1045 if (htab->tlsdesc_plt)
1046 {
1047 /* NB: tlsdesc_plt is set only for x86-64. If we're not using
1048 lazy TLS relocations, don't generate the PLT and GOT entries
1049 they require. */
1050 if ((info->flags & DF_BIND_NOW))
1051 htab->tlsdesc_plt = 0;
1052 else
1053 {
1054 htab->tlsdesc_got = htab->elf.sgot->size;
1055 htab->elf.sgot->size += htab->got_entry_size;
1056 /* Reserve room for the initial entry.
1057 FIXME: we could probably do away with it in this case. */
1058 if (htab->elf.splt->size == 0)
1059 htab->elf.splt->size = htab->plt.plt_entry_size;
1060 htab->tlsdesc_plt = htab->elf.splt->size;
1061 htab->elf.splt->size += htab->plt.plt_entry_size;
1062 }
1063 }
1064
1065 if (htab->elf.sgotplt)
1066 {
1067 /* Don't allocate .got.plt section if there are no GOT nor PLT
1068 entries and there is no reference to _GLOBAL_OFFSET_TABLE_. */
1069 if ((htab->elf.hgot == NULL
1070 || !htab->elf.hgot->ref_regular_nonweak)
1071 && (htab->elf.sgotplt->size == bed->got_header_size)
1072 && (htab->elf.splt == NULL
1073 || htab->elf.splt->size == 0)
1074 && (htab->elf.sgot == NULL
1075 || htab->elf.sgot->size == 0)
1076 && (htab->elf.iplt == NULL
1077 || htab->elf.iplt->size == 0)
1078 && (htab->elf.igotplt == NULL
1079 || htab->elf.igotplt->size == 0))
1080 htab->elf.sgotplt->size = 0;
1081 }
1082
1083 if (_bfd_elf_eh_frame_present (info))
1084 {
1085 if (htab->plt_eh_frame != NULL
1086 && htab->elf.splt != NULL
1087 && htab->elf.splt->size != 0
1088 && !bfd_is_abs_section (htab->elf.splt->output_section))
1089 htab->plt_eh_frame->size = htab->plt.eh_frame_plt_size;
1090
1091 if (htab->plt_got_eh_frame != NULL
1092 && htab->plt_got != NULL
1093 && htab->plt_got->size != 0
1094 && !bfd_is_abs_section (htab->plt_got->output_section))
1095 htab->plt_got_eh_frame->size
1096 = htab->non_lazy_plt->eh_frame_plt_size;
1097
1098 /* Unwind info for the second PLT and .plt.got sections are
1099 identical. */
1100 if (htab->plt_second_eh_frame != NULL
1101 && htab->plt_second != NULL
1102 && htab->plt_second->size != 0
1103 && !bfd_is_abs_section (htab->plt_second->output_section))
1104 htab->plt_second_eh_frame->size
1105 = htab->non_lazy_plt->eh_frame_plt_size;
1106 }
1107
1108 /* We now have determined the sizes of the various dynamic sections.
1109 Allocate memory for them. */
1110 relocs = FALSE;
1111 for (s = dynobj->sections; s != NULL; s = s->next)
1112 {
1113 bfd_boolean strip_section = TRUE;
1114
1115 if ((s->flags & SEC_LINKER_CREATED) == 0)
1116 continue;
1117
1118 if (s == htab->elf.splt
1119 || s == htab->elf.sgot)
1120 {
1121 /* Strip this section if we don't need it; see the
1122 comment below. */
1123 /* We'd like to strip these sections if they aren't needed, but if
1124 we've exported dynamic symbols from them we must leave them.
1125 It's too late to tell BFD to get rid of the symbols. */
1126
1127 if (htab->elf.hplt != NULL)
1128 strip_section = FALSE;
1129 }
1130 else if (s == htab->elf.sgotplt
1131 || s == htab->elf.iplt
1132 || s == htab->elf.igotplt
1133 || s == htab->plt_second
1134 || s == htab->plt_got
1135 || s == htab->plt_eh_frame
1136 || s == htab->plt_got_eh_frame
1137 || s == htab->plt_second_eh_frame
1138 || s == htab->elf.sdynbss
1139 || s == htab->elf.sdynrelro)
1140 {
1141 /* Strip these too. */
1142 }
1143 else if (htab->is_reloc_section (bfd_get_section_name (dynobj, s)))
1144 {
1145 if (s->size != 0
1146 && s != htab->elf.srelplt
1147 && s != htab->srelplt2)
1148 relocs = TRUE;
1149
1150 /* We use the reloc_count field as a counter if we need
1151 to copy relocs into the output file. */
1152 if (s != htab->elf.srelplt)
1153 s->reloc_count = 0;
1154 }
1155 else
1156 {
1157 /* It's not one of our sections, so don't allocate space. */
1158 continue;
1159 }
1160
1161 if (s->size == 0)
1162 {
1163 /* If we don't need this section, strip it from the
1164 output file. This is mostly to handle .rel.bss and
1165 .rel.plt. We must create both sections in
1166 create_dynamic_sections, because they must be created
1167 before the linker maps input sections to output
1168 sections. The linker does that before
1169 adjust_dynamic_symbol is called, and it is that
1170 function which decides whether anything needs to go
1171 into these sections. */
1172 if (strip_section)
1173 s->flags |= SEC_EXCLUDE;
1174 continue;
1175 }
1176
1177 if ((s->flags & SEC_HAS_CONTENTS) == 0)
1178 continue;
1179
1180 /* Allocate memory for the section contents. We use bfd_zalloc
1181 here in case unused entries are not reclaimed before the
1182 section's contents are written out. This should not happen,
1183 but this way if it does, we get a R_386_NONE or R_X86_64_NONE
1184 reloc instead of garbage. */
1185 s->contents = (unsigned char *) bfd_zalloc (dynobj, s->size);
1186 if (s->contents == NULL)
1187 return FALSE;
1188 }
1189
1190 if (htab->plt_eh_frame != NULL
1191 && htab->plt_eh_frame->contents != NULL)
1192 {
1193 memcpy (htab->plt_eh_frame->contents,
1194 htab->plt.eh_frame_plt,
1195 htab->plt_eh_frame->size);
1196 bfd_put_32 (dynobj, htab->elf.splt->size,
1197 htab->plt_eh_frame->contents + PLT_FDE_LEN_OFFSET);
1198 }
1199
1200 if (htab->plt_got_eh_frame != NULL
1201 && htab->plt_got_eh_frame->contents != NULL)
1202 {
1203 memcpy (htab->plt_got_eh_frame->contents,
1204 htab->non_lazy_plt->eh_frame_plt,
1205 htab->plt_got_eh_frame->size);
1206 bfd_put_32 (dynobj, htab->plt_got->size,
1207 (htab->plt_got_eh_frame->contents
1208 + PLT_FDE_LEN_OFFSET));
1209 }
1210
1211 if (htab->plt_second_eh_frame != NULL
1212 && htab->plt_second_eh_frame->contents != NULL)
1213 {
1214 memcpy (htab->plt_second_eh_frame->contents,
1215 htab->non_lazy_plt->eh_frame_plt,
1216 htab->plt_second_eh_frame->size);
1217 bfd_put_32 (dynobj, htab->plt_second->size,
1218 (htab->plt_second_eh_frame->contents
1219 + PLT_FDE_LEN_OFFSET));
1220 }
1221
1222 if (htab->elf.dynamic_sections_created)
1223 {
1224 /* Add some entries to the .dynamic section. We fill in the
1225 values later, in elf_{i386,x86_64}_finish_dynamic_sections,
1226 but we must add the entries now so that we get the correct
1227 size for the .dynamic section. The DT_DEBUG entry is filled
1228 in by the dynamic linker and used by the debugger. */
1229 #define add_dynamic_entry(TAG, VAL) \
1230 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
1231
1232 if (bfd_link_executable (info))
1233 {
1234 if (!add_dynamic_entry (DT_DEBUG, 0))
1235 return FALSE;
1236 }
1237
1238 if (htab->elf.splt->size != 0)
1239 {
1240 /* DT_PLTGOT is used by prelink even if there is no PLT
1241 relocation. */
1242 if (!add_dynamic_entry (DT_PLTGOT, 0))
1243 return FALSE;
1244 }
1245
1246 if (htab->elf.srelplt->size != 0)
1247 {
1248 if (!add_dynamic_entry (DT_PLTRELSZ, 0)
1249 || !add_dynamic_entry (DT_PLTREL, htab->dt_reloc)
1250 || !add_dynamic_entry (DT_JMPREL, 0))
1251 return FALSE;
1252 }
1253
1254 if (htab->tlsdesc_plt
1255 && (!add_dynamic_entry (DT_TLSDESC_PLT, 0)
1256 || !add_dynamic_entry (DT_TLSDESC_GOT, 0)))
1257 return FALSE;
1258
1259 if (relocs)
1260 {
1261 if (!add_dynamic_entry (htab->dt_reloc, 0)
1262 || !add_dynamic_entry (htab->dt_reloc_sz, 0)
1263 || !add_dynamic_entry (htab->dt_reloc_ent,
1264 htab->sizeof_reloc))
1265 return FALSE;
1266
1267 /* If any dynamic relocs apply to a read-only section,
1268 then we need a DT_TEXTREL entry. */
1269 if ((info->flags & DF_TEXTREL) == 0)
1270 elf_link_hash_traverse (&htab->elf,
1271 _bfd_x86_elf_readonly_dynrelocs,
1272 info);
1273
1274 if ((info->flags & DF_TEXTREL) != 0)
1275 {
1276 if (htab->readonly_dynrelocs_against_ifunc)
1277 {
1278 info->callbacks->einfo
1279 (_("%P%X: read-only segment has dynamic IFUNC relocations; recompile with -fPIC\n"));
1280 bfd_set_error (bfd_error_bad_value);
1281 return FALSE;
1282 }
1283
1284 if (!add_dynamic_entry (DT_TEXTREL, 0))
1285 return FALSE;
1286 }
1287 }
1288 if (htab->is_vxworks
1289 && !elf_vxworks_add_dynamic_entries (output_bfd, info))
1290 return FALSE;
1291 }
1292 #undef add_dynamic_entry
1293
1294 return TRUE;
1295 }
1296
1297 bfd_boolean
1298 _bfd_x86_elf_always_size_sections (bfd *output_bfd,
1299 struct bfd_link_info *info)
1300 {
1301 asection *tls_sec = elf_hash_table (info)->tls_sec;
1302
1303 if (tls_sec)
1304 {
1305 struct elf_link_hash_entry *tlsbase;
1306
1307 tlsbase = elf_link_hash_lookup (elf_hash_table (info),
1308 "_TLS_MODULE_BASE_",
1309 FALSE, FALSE, FALSE);
1310
1311 if (tlsbase && tlsbase->type == STT_TLS)
1312 {
1313 struct elf_x86_link_hash_table *htab;
1314 struct bfd_link_hash_entry *bh = NULL;
1315 const struct elf_backend_data *bed
1316 = get_elf_backend_data (output_bfd);
1317
1318 htab = elf_x86_hash_table (info, bed->target_id);
1319 if (htab == NULL)
1320 return FALSE;
1321
1322 if (!(_bfd_generic_link_add_one_symbol
1323 (info, output_bfd, "_TLS_MODULE_BASE_", BSF_LOCAL,
1324 tls_sec, 0, NULL, FALSE,
1325 bed->collect, &bh)))
1326 return FALSE;
1327
1328 htab->tls_module_base = bh;
1329
1330 tlsbase = (struct elf_link_hash_entry *)bh;
1331 tlsbase->def_regular = 1;
1332 tlsbase->other = STV_HIDDEN;
1333 tlsbase->root.linker_def = 1;
1334 (*bed->elf_backend_hide_symbol) (info, tlsbase, TRUE);
1335 }
1336 }
1337
1338 return TRUE;
1339 }
1340
1341 void
1342 _bfd_x86_elf_merge_symbol_attribute (struct elf_link_hash_entry *h,
1343 const Elf_Internal_Sym *isym,
1344 bfd_boolean definition,
1345 bfd_boolean dynamic ATTRIBUTE_UNUSED)
1346 {
1347 if (definition)
1348 {
1349 struct elf_x86_link_hash_entry *eh
1350 = (struct elf_x86_link_hash_entry *) h;
1351 eh->def_protected = (ELF_ST_VISIBILITY (isym->st_other)
1352 == STV_PROTECTED);
1353 }
1354 }
1355
1356 /* Copy the extra info we tack onto an elf_link_hash_entry. */
1357
1358 void
1359 _bfd_x86_elf_copy_indirect_symbol (struct bfd_link_info *info,
1360 struct elf_link_hash_entry *dir,
1361 struct elf_link_hash_entry *ind)
1362 {
1363 struct elf_x86_link_hash_entry *edir, *eind;
1364
1365 edir = (struct elf_x86_link_hash_entry *) dir;
1366 eind = (struct elf_x86_link_hash_entry *) ind;
1367
1368 if (eind->dyn_relocs != NULL)
1369 {
1370 if (edir->dyn_relocs != NULL)
1371 {
1372 struct elf_dyn_relocs **pp;
1373 struct elf_dyn_relocs *p;
1374
1375 /* Add reloc counts against the indirect sym to the direct sym
1376 list. Merge any entries against the same section. */
1377 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
1378 {
1379 struct elf_dyn_relocs *q;
1380
1381 for (q = edir->dyn_relocs; q != NULL; q = q->next)
1382 if (q->sec == p->sec)
1383 {
1384 q->pc_count += p->pc_count;
1385 q->count += p->count;
1386 *pp = p->next;
1387 break;
1388 }
1389 if (q == NULL)
1390 pp = &p->next;
1391 }
1392 *pp = edir->dyn_relocs;
1393 }
1394
1395 edir->dyn_relocs = eind->dyn_relocs;
1396 eind->dyn_relocs = NULL;
1397 }
1398
1399 if (ind->root.type == bfd_link_hash_indirect
1400 && dir->got.refcount <= 0)
1401 {
1402 edir->tls_type = eind->tls_type;
1403 eind->tls_type = GOT_UNKNOWN;
1404 }
1405
1406 /* Copy gotoff_ref so that elf_i386_adjust_dynamic_symbol will
1407 generate a R_386_COPY reloc. */
1408 edir->gotoff_ref |= eind->gotoff_ref;
1409
1410 edir->zero_undefweak |= eind->zero_undefweak;
1411
1412 if (ELIMINATE_COPY_RELOCS
1413 && ind->root.type != bfd_link_hash_indirect
1414 && dir->dynamic_adjusted)
1415 {
1416 /* If called to transfer flags for a weakdef during processing
1417 of elf_adjust_dynamic_symbol, don't copy non_got_ref.
1418 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
1419 if (dir->versioned != versioned_hidden)
1420 dir->ref_dynamic |= ind->ref_dynamic;
1421 dir->ref_regular |= ind->ref_regular;
1422 dir->ref_regular_nonweak |= ind->ref_regular_nonweak;
1423 dir->needs_plt |= ind->needs_plt;
1424 dir->pointer_equality_needed |= ind->pointer_equality_needed;
1425 }
1426 else
1427 {
1428 if (eind->func_pointer_refcount > 0)
1429 {
1430 edir->func_pointer_refcount += eind->func_pointer_refcount;
1431 eind->func_pointer_refcount = 0;
1432 }
1433
1434 _bfd_elf_link_hash_copy_indirect (info, dir, ind);
1435 }
1436 }
1437
1438 /* Remove undefined weak symbol from the dynamic symbol table if it
1439 is resolved to 0. */
1440
1441 bfd_boolean
1442 _bfd_x86_elf_fixup_symbol (struct bfd_link_info *info,
1443 struct elf_link_hash_entry *h)
1444 {
1445 if (h->dynindx != -1
1446 && UNDEFINED_WEAK_RESOLVED_TO_ZERO (info, elf_x86_hash_entry (h)))
1447 {
1448 h->dynindx = -1;
1449 _bfd_elf_strtab_delref (elf_hash_table (info)->dynstr,
1450 h->dynstr_index);
1451 }
1452 return TRUE;
1453 }
1454
1455 /* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */
1456
1457 bfd_boolean
1458 _bfd_x86_elf_hash_symbol (struct elf_link_hash_entry *h)
1459 {
1460 if (h->plt.offset != (bfd_vma) -1
1461 && !h->def_regular
1462 && !h->pointer_equality_needed)
1463 return FALSE;
1464
1465 return _bfd_elf_hash_symbol (h);
1466 }
1467
1468 /* Adjust a symbol defined by a dynamic object and referenced by a
1469 regular object. The current definition is in some section of the
1470 dynamic object, but we're not including those sections. We have to
1471 change the definition to something the rest of the link can
1472 understand. */
1473
1474 bfd_boolean
1475 _bfd_x86_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
1476 struct elf_link_hash_entry *h)
1477 {
1478 struct elf_x86_link_hash_table *htab;
1479 asection *s, *srel;
1480 struct elf_x86_link_hash_entry *eh;
1481 struct elf_dyn_relocs *p;
1482 const struct elf_backend_data *bed
1483 = get_elf_backend_data (info->output_bfd);
1484
1485 /* STT_GNU_IFUNC symbol must go through PLT. */
1486 if (h->type == STT_GNU_IFUNC)
1487 {
1488 /* All local STT_GNU_IFUNC references must be treate as local
1489 calls via local PLT. */
1490 if (h->ref_regular
1491 && SYMBOL_CALLS_LOCAL (info, h))
1492 {
1493 bfd_size_type pc_count = 0, count = 0;
1494 struct elf_dyn_relocs **pp;
1495
1496 eh = (struct elf_x86_link_hash_entry *) h;
1497 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1498 {
1499 pc_count += p->pc_count;
1500 p->count -= p->pc_count;
1501 p->pc_count = 0;
1502 count += p->count;
1503 if (p->count == 0)
1504 *pp = p->next;
1505 else
1506 pp = &p->next;
1507 }
1508
1509 if (pc_count || count)
1510 {
1511 h->non_got_ref = 1;
1512 if (pc_count)
1513 {
1514 /* Increment PLT reference count only for PC-relative
1515 references. */
1516 h->needs_plt = 1;
1517 if (h->plt.refcount <= 0)
1518 h->plt.refcount = 1;
1519 else
1520 h->plt.refcount += 1;
1521 }
1522 }
1523 }
1524
1525 if (h->plt.refcount <= 0)
1526 {
1527 h->plt.offset = (bfd_vma) -1;
1528 h->needs_plt = 0;
1529 }
1530 return TRUE;
1531 }
1532
1533 /* If this is a function, put it in the procedure linkage table. We
1534 will fill in the contents of the procedure linkage table later,
1535 when we know the address of the .got section. */
1536 if (h->type == STT_FUNC
1537 || h->needs_plt)
1538 {
1539 if (h->plt.refcount <= 0
1540 || SYMBOL_CALLS_LOCAL (info, h)
1541 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1542 && h->root.type == bfd_link_hash_undefweak))
1543 {
1544 /* This case can occur if we saw a PLT32 reloc in an input
1545 file, but the symbol was never referred to by a dynamic
1546 object, or if all references were garbage collected. In
1547 such a case, we don't actually need to build a procedure
1548 linkage table, and we can just do a PC32 reloc instead. */
1549 h->plt.offset = (bfd_vma) -1;
1550 h->needs_plt = 0;
1551 }
1552
1553 return TRUE;
1554 }
1555 else
1556 /* It's possible that we incorrectly decided a .plt reloc was needed
1557 * for an R_386_PC32/R_X86_64_PC32 reloc to a non-function sym in
1558 check_relocs. We can't decide accurately between function and
1559 non-function syms in check-relocs; Objects loaded later in
1560 the link may change h->type. So fix it now. */
1561 h->plt.offset = (bfd_vma) -1;
1562
1563 eh = (struct elf_x86_link_hash_entry *) h;
1564
1565 /* If this is a weak symbol, and there is a real definition, the
1566 processor independent code will have arranged for us to see the
1567 real definition first, and we can just use the same value. */
1568 if (h->u.weakdef != NULL)
1569 {
1570 BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined
1571 || h->u.weakdef->root.type == bfd_link_hash_defweak);
1572 h->root.u.def.section = h->u.weakdef->root.u.def.section;
1573 h->root.u.def.value = h->u.weakdef->root.u.def.value;
1574 if (ELIMINATE_COPY_RELOCS
1575 || info->nocopyreloc
1576 || SYMBOL_NO_COPYRELOC (info, eh))
1577 {
1578 /* NB: needs_copy is always 0 for i386. */
1579 h->non_got_ref = h->u.weakdef->non_got_ref;
1580 eh->needs_copy = h->u.weakdef->needs_copy;
1581 }
1582 return TRUE;
1583 }
1584
1585 /* This is a reference to a symbol defined by a dynamic object which
1586 is not a function. */
1587
1588 /* If we are creating a shared library, we must presume that the
1589 only references to the symbol are via the global offset table.
1590 For such cases we need not do anything here; the relocations will
1591 be handled correctly by relocate_section. */
1592 if (!bfd_link_executable (info))
1593 return TRUE;
1594
1595 /* If there are no references to this symbol that do not use the
1596 GOT nor R_386_GOTOFF relocation, we don't need to generate a copy
1597 reloc. NB: gotoff_ref is always 0 for x86-64. */
1598 if (!h->non_got_ref && !eh->gotoff_ref)
1599 return TRUE;
1600
1601 /* If -z nocopyreloc was given, we won't generate them either. */
1602 if (info->nocopyreloc || SYMBOL_NO_COPYRELOC (info, eh))
1603 {
1604 h->non_got_ref = 0;
1605 return TRUE;
1606 }
1607
1608 htab = elf_x86_hash_table (info, bed->target_id);
1609 if (htab == NULL)
1610 return FALSE;
1611
1612 /* If there aren't any dynamic relocs in read-only sections nor
1613 R_386_GOTOFF relocation, then we can keep the dynamic relocs and
1614 avoid the copy reloc. This doesn't work on VxWorks, where we can
1615 not have dynamic relocations (other than copy and jump slot
1616 relocations) in an executable. */
1617 if (ELIMINATE_COPY_RELOCS
1618 && (bed->target_id == X86_64_ELF_DATA
1619 || (!eh->gotoff_ref
1620 && !htab->is_vxworks)))
1621 {
1622 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1623 {
1624 s = p->sec->output_section;
1625 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1626 break;
1627 }
1628
1629 /* If we didn't find any dynamic relocs in read-only sections,
1630 then we'll be keeping the dynamic relocs and avoiding the copy
1631 reloc. */
1632 if (p == NULL)
1633 {
1634 h->non_got_ref = 0;
1635 return TRUE;
1636 }
1637 }
1638
1639 /* We must allocate the symbol in our .dynbss section, which will
1640 become part of the .bss section of the executable. There will be
1641 an entry for this symbol in the .dynsym section. The dynamic
1642 object will contain position independent code, so all references
1643 from the dynamic object to this symbol will go through the global
1644 offset table. The dynamic linker will use the .dynsym entry to
1645 determine the address it must put in the global offset table, so
1646 both the dynamic object and the regular object will refer to the
1647 same memory location for the variable. */
1648
1649 /* We must generate a R_386_COPY/R_X86_64_COPY reloc to tell the
1650 dynamic linker to copy the initial value out of the dynamic object
1651 and into the runtime process image. */
1652 if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
1653 {
1654 s = htab->elf.sdynrelro;
1655 srel = htab->elf.sreldynrelro;
1656 }
1657 else
1658 {
1659 s = htab->elf.sdynbss;
1660 srel = htab->elf.srelbss;
1661 }
1662 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
1663 {
1664 srel->size += htab->sizeof_reloc;
1665 h->needs_copy = 1;
1666 }
1667
1668 return _bfd_elf_adjust_dynamic_copy (info, h, s);
1669 }
1670
1671 void
1672 _bfd_x86_elf_hide_symbol (struct bfd_link_info *info,
1673 struct elf_link_hash_entry *h,
1674 bfd_boolean force_local)
1675 {
1676 if (h->root.type == bfd_link_hash_undefweak
1677 && info->nointerp
1678 && bfd_link_pie (info))
1679 {
1680 /* When there is no dynamic interpreter in PIE, make the undefined
1681 weak symbol dynamic so that PC relative branch to the undefined
1682 weak symbol will land to address 0. */
1683 struct elf_x86_link_hash_entry *eh = elf_x86_hash_entry (h);
1684 if (h->plt.refcount > eh->func_pointer_refcount
1685 || eh->plt_got.refcount > 0)
1686 return;
1687 }
1688
1689 _bfd_elf_link_hash_hide_symbol (info, h, force_local);
1690 }
1691
1692 /* Return TRUE if a symbol is referenced locally. It is similar to
1693 SYMBOL_REFERENCES_LOCAL, but it also checks version script. It
1694 works in check_relocs. */
1695
1696 bfd_boolean
1697 _bfd_x86_elf_link_symbol_references_local (struct bfd_link_info *info,
1698 struct elf_link_hash_entry *h)
1699 {
1700 struct elf_x86_link_hash_entry *eh = elf_x86_hash_entry (h);
1701 struct elf_x86_link_hash_table *htab
1702 = (struct elf_x86_link_hash_table *) info->hash;
1703
1704 if (eh->local_ref > 1)
1705 return TRUE;
1706
1707 if (eh->local_ref == 1)
1708 return FALSE;
1709
1710 /* Unversioned symbols defined in regular objects can be forced local
1711 by linker version script. A weak undefined symbol is forced local
1712 if
1713 1. It has non-default visibility. Or
1714 2. When building executable, there is no dynamic linker. Or
1715 3. or "-z nodynamic-undefined-weak" is used.
1716 */
1717 if (SYMBOL_REFERENCES_LOCAL (info, h)
1718 || (h->root.type == bfd_link_hash_undefweak
1719 && (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1720 || (bfd_link_executable (info)
1721 && htab->interp == NULL)
1722 || info->dynamic_undefined_weak == 0))
1723 || ((h->def_regular || ELF_COMMON_DEF_P (h))
1724 && h->versioned == unversioned
1725 && info->version_info != NULL
1726 && bfd_hide_sym_by_version (info->version_info,
1727 h->root.root.string)))
1728 {
1729 eh->local_ref = 2;
1730 return TRUE;
1731 }
1732
1733 eh->local_ref = 1;
1734 return FALSE;
1735 }
1736
1737 /* Return the section that should be marked against GC for a given
1738 relocation. */
1739
1740 asection *
1741 _bfd_x86_elf_gc_mark_hook (asection *sec,
1742 struct bfd_link_info *info,
1743 Elf_Internal_Rela *rel,
1744 struct elf_link_hash_entry *h,
1745 Elf_Internal_Sym *sym)
1746 {
1747 /* Compiler should optimize this out. */
1748 if (((unsigned int) R_X86_64_GNU_VTINHERIT
1749 != (unsigned int) R_386_GNU_VTINHERIT)
1750 || ((unsigned int) R_X86_64_GNU_VTENTRY
1751 != (unsigned int) R_386_GNU_VTENTRY))
1752 abort ();
1753
1754 if (h != NULL)
1755 switch (ELF32_R_TYPE (rel->r_info))
1756 {
1757 case R_X86_64_GNU_VTINHERIT:
1758 case R_X86_64_GNU_VTENTRY:
1759 return NULL;
1760 }
1761
1762 return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
1763 }
1764
1765 static bfd_vma
1766 elf_i386_get_plt_got_vma (struct elf_x86_plt *plt_p ATTRIBUTE_UNUSED,
1767 bfd_vma off,
1768 bfd_vma offset ATTRIBUTE_UNUSED,
1769 bfd_vma got_addr)
1770 {
1771 return got_addr + off;
1772 }
1773
1774 static bfd_vma
1775 elf_x86_64_get_plt_got_vma (struct elf_x86_plt *plt_p,
1776 bfd_vma off,
1777 bfd_vma offset,
1778 bfd_vma got_addr ATTRIBUTE_UNUSED)
1779 {
1780 return plt_p->sec->vma + offset + off + plt_p->plt_got_insn_size;
1781 }
1782
1783 static bfd_boolean
1784 elf_i386_valid_plt_reloc_p (unsigned int type)
1785 {
1786 return (type == R_386_JUMP_SLOT
1787 || type == R_386_GLOB_DAT
1788 || type == R_386_IRELATIVE);
1789 }
1790
1791 static bfd_boolean
1792 elf_x86_64_valid_plt_reloc_p (unsigned int type)
1793 {
1794 return (type == R_X86_64_JUMP_SLOT
1795 || type == R_X86_64_GLOB_DAT
1796 || type == R_X86_64_IRELATIVE);
1797 }
1798
1799 long
1800 _bfd_x86_elf_get_synthetic_symtab (bfd *abfd,
1801 long count,
1802 long relsize,
1803 bfd_vma got_addr,
1804 struct elf_x86_plt plts[],
1805 asymbol **dynsyms,
1806 asymbol **ret)
1807 {
1808 long size, i, n, len;
1809 int j;
1810 unsigned int plt_got_offset, plt_entry_size;
1811 asymbol *s;
1812 bfd_byte *plt_contents;
1813 long dynrelcount;
1814 arelent **dynrelbuf, *p;
1815 char *names;
1816 const struct elf_backend_data *bed;
1817 bfd_vma (*get_plt_got_vma) (struct elf_x86_plt *, bfd_vma, bfd_vma,
1818 bfd_vma);
1819 bfd_boolean (*valid_plt_reloc_p) (unsigned int);
1820
1821 if (count == 0)
1822 return -1;
1823
1824 dynrelbuf = (arelent **) bfd_malloc (relsize);
1825 if (dynrelbuf == NULL)
1826 return -1;
1827
1828 dynrelcount = bfd_canonicalize_dynamic_reloc (abfd, dynrelbuf,
1829 dynsyms);
1830 if (dynrelcount <= 0)
1831 return -1;
1832
1833 /* Sort the relocs by address. */
1834 qsort (dynrelbuf, dynrelcount, sizeof (arelent *),
1835 _bfd_x86_elf_compare_relocs);
1836
1837 size = count * sizeof (asymbol);
1838
1839 /* Allocate space for @plt suffixes. */
1840 n = 0;
1841 for (i = 0; i < dynrelcount; i++)
1842 {
1843 p = dynrelbuf[i];
1844 size += strlen ((*p->sym_ptr_ptr)->name) + sizeof ("@plt");
1845 if (p->addend != 0)
1846 size += sizeof ("+0x") - 1 + 8 + 8 * ABI_64_P (abfd);
1847 }
1848
1849 s = *ret = (asymbol *) bfd_zmalloc (size);
1850 if (s == NULL)
1851 goto bad_return;
1852
1853 bed = get_elf_backend_data (abfd);
1854
1855 if (bed->target_id == X86_64_ELF_DATA)
1856 {
1857 get_plt_got_vma = elf_x86_64_get_plt_got_vma;
1858 valid_plt_reloc_p = elf_x86_64_valid_plt_reloc_p;
1859 }
1860 else
1861 {
1862 get_plt_got_vma = elf_i386_get_plt_got_vma;
1863 valid_plt_reloc_p = elf_i386_valid_plt_reloc_p;
1864 if (got_addr)
1865 {
1866 /* Check .got.plt and then .got to get the _GLOBAL_OFFSET_TABLE_
1867 address. */
1868 asection *sec = bfd_get_section_by_name (abfd, ".got.plt");
1869 if (sec != NULL)
1870 got_addr = sec->vma;
1871 else
1872 {
1873 sec = bfd_get_section_by_name (abfd, ".got");
1874 if (sec != NULL)
1875 got_addr = sec->vma;
1876 }
1877
1878 if (got_addr == (bfd_vma) -1)
1879 goto bad_return;
1880 }
1881 }
1882
1883 /* Check for each PLT section. */
1884 names = (char *) (s + count);
1885 size = 0;
1886 n = 0;
1887 for (j = 0; plts[j].name != NULL; j++)
1888 if ((plt_contents = plts[j].contents) != NULL)
1889 {
1890 long k;
1891 bfd_vma offset;
1892 asection *plt;
1893 struct elf_x86_plt *plt_p = &plts[j];
1894
1895 plt_got_offset = plt_p->plt_got_offset;
1896 plt_entry_size = plt_p->plt_entry_size;
1897
1898 plt = plt_p->sec;
1899
1900 if ((plt_p->type & plt_lazy))
1901 {
1902 /* Skip PLT0 in lazy PLT. */
1903 k = 1;
1904 offset = plt_entry_size;
1905 }
1906 else
1907 {
1908 k = 0;
1909 offset = 0;
1910 }
1911
1912 /* Check each PLT entry against dynamic relocations. */
1913 for (; k < plt_p->count; k++)
1914 {
1915 int off;
1916 bfd_vma got_vma;
1917 long min, max, mid;
1918
1919 /* Get the GOT offset for i386 or the PC-relative offset
1920 for x86-64, a signed 32-bit integer. */
1921 off = H_GET_32 (abfd, (plt_contents + offset
1922 + plt_got_offset));
1923 got_vma = get_plt_got_vma (plt_p, off, offset, got_addr);
1924
1925 /* Binary search. */
1926 p = dynrelbuf[0];
1927 min = 0;
1928 max = dynrelcount;
1929 while ((min + 1) < max)
1930 {
1931 arelent *r;
1932
1933 mid = (min + max) / 2;
1934 r = dynrelbuf[mid];
1935 if (got_vma > r->address)
1936 min = mid;
1937 else if (got_vma < r->address)
1938 max = mid;
1939 else
1940 {
1941 p = r;
1942 break;
1943 }
1944 }
1945
1946 /* Skip unknown relocation. PR 17512: file: bc9d6cf5. */
1947 if (got_vma == p->address
1948 && p->howto != NULL
1949 && valid_plt_reloc_p (p->howto->type))
1950 {
1951 *s = **p->sym_ptr_ptr;
1952 /* Undefined syms won't have BSF_LOCAL or BSF_GLOBAL
1953 set. Since we are defining a symbol, ensure one
1954 of them is set. */
1955 if ((s->flags & BSF_LOCAL) == 0)
1956 s->flags |= BSF_GLOBAL;
1957 s->flags |= BSF_SYNTHETIC;
1958 /* This is no longer a section symbol. */
1959 s->flags &= ~BSF_SECTION_SYM;
1960 s->section = plt;
1961 s->the_bfd = plt->owner;
1962 s->value = offset;
1963 s->udata.p = NULL;
1964 s->name = names;
1965 len = strlen ((*p->sym_ptr_ptr)->name);
1966 memcpy (names, (*p->sym_ptr_ptr)->name, len);
1967 names += len;
1968 if (p->addend != 0)
1969 {
1970 char buf[30], *a;
1971
1972 memcpy (names, "+0x", sizeof ("+0x") - 1);
1973 names += sizeof ("+0x") - 1;
1974 bfd_sprintf_vma (abfd, buf, p->addend);
1975 for (a = buf; *a == '0'; ++a)
1976 ;
1977 size = strlen (a);
1978 memcpy (names, a, size);
1979 names += size;
1980 }
1981 memcpy (names, "@plt", sizeof ("@plt"));
1982 names += sizeof ("@plt");
1983 n++;
1984 s++;
1985 /* There should be only one entry in PLT for a given
1986 symbol. Set howto to NULL after processing a PLT
1987 entry to guard against corrupted PLT. */
1988 p->howto = NULL;
1989 }
1990 offset += plt_entry_size;
1991 }
1992 }
1993
1994 /* PLT entries with R_386_TLS_DESC relocations are skipped. */
1995 if (n == 0)
1996 {
1997 bad_return:
1998 count = -1;
1999 }
2000 else
2001 count = n;
2002
2003 for (j = 0; plts[j].name != NULL; j++)
2004 if (plts[j].contents != NULL)
2005 free (plts[j].contents);
2006
2007 free (dynrelbuf);
2008
2009 return count;
2010 }
2011
2012 /* Parse x86 GNU properties. */
2013
2014 enum elf_property_kind
2015 _bfd_x86_elf_parse_gnu_properties (bfd *abfd, unsigned int type,
2016 bfd_byte *ptr, unsigned int datasz)
2017 {
2018 elf_property *prop;
2019
2020 switch (type)
2021 {
2022 case GNU_PROPERTY_X86_ISA_1_USED:
2023 case GNU_PROPERTY_X86_ISA_1_NEEDED:
2024 case GNU_PROPERTY_X86_FEATURE_1_AND:
2025 if (datasz != 4)
2026 {
2027 _bfd_error_handler
2028 ((type == GNU_PROPERTY_X86_ISA_1_USED
2029 ? _("error: %B: <corrupt x86 ISA used size: 0x%x>")
2030 : (type == GNU_PROPERTY_X86_ISA_1_NEEDED
2031 ? _("error: %B: <corrupt x86 ISA needed size: 0x%x>")
2032 : _("error: %B: <corrupt x86 feature size: 0x%x>"))),
2033 abfd, datasz);
2034 return property_corrupt;
2035 }
2036 prop = _bfd_elf_get_property (abfd, type, datasz);
2037 /* Combine properties of the same type. */
2038 prop->u.number |= bfd_h_get_32 (abfd, ptr);
2039 prop->pr_kind = property_number;
2040 break;
2041
2042 default:
2043 return property_ignored;
2044 }
2045
2046 return property_number;
2047 }
2048
2049 /* Merge x86 GNU property BPROP with APROP. If APROP isn't NULL,
2050 return TRUE if APROP is updated. Otherwise, return TRUE if BPROP
2051 should be merged with ABFD. */
2052
2053 bfd_boolean
2054 _bfd_x86_elf_merge_gnu_properties (struct bfd_link_info *info,
2055 bfd *abfd ATTRIBUTE_UNUSED,
2056 elf_property *aprop,
2057 elf_property *bprop)
2058 {
2059 unsigned int number, features;
2060 bfd_boolean updated = FALSE;
2061 unsigned int pr_type = aprop != NULL ? aprop->pr_type : bprop->pr_type;
2062
2063 switch (pr_type)
2064 {
2065 case GNU_PROPERTY_X86_ISA_1_USED:
2066 case GNU_PROPERTY_X86_ISA_1_NEEDED:
2067 if (aprop != NULL && bprop != NULL)
2068 {
2069 number = aprop->u.number;
2070 aprop->u.number = number | bprop->u.number;
2071 updated = number != (unsigned int) aprop->u.number;
2072 }
2073 else
2074 {
2075 /* Return TRUE if APROP is NULL to indicate that BPROP should
2076 be added to ABFD. */
2077 updated = aprop == NULL;
2078 }
2079 break;
2080
2081 case GNU_PROPERTY_X86_FEATURE_1_AND:
2082 /* Only one of APROP and BPROP can be NULL:
2083 1. APROP & BPROP when both APROP and BPROP aren't NULL.
2084 2. If APROP is NULL, remove x86 feature.
2085 3. Otherwise, do nothing.
2086 */
2087 if (aprop != NULL && bprop != NULL)
2088 {
2089 features = 0;
2090 if (info->ibt)
2091 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2092 if (info->shstk)
2093 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2094 number = aprop->u.number;
2095 /* Add GNU_PROPERTY_X86_FEATURE_1_IBT and
2096 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2097 aprop->u.number = (number & bprop->u.number) | features;
2098 updated = number != (unsigned int) aprop->u.number;
2099 /* Remove the property if all feature bits are cleared. */
2100 if (aprop->u.number == 0)
2101 aprop->pr_kind = property_remove;
2102 }
2103 else
2104 {
2105 features = 0;
2106 if (info->ibt)
2107 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2108 if (info->shstk)
2109 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2110 if (features)
2111 {
2112 /* Add GNU_PROPERTY_X86_FEATURE_1_IBT and
2113 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2114 if (aprop != NULL)
2115 {
2116 number = aprop->u.number;
2117 aprop->u.number = number | features;
2118 updated = number != (unsigned int) aprop->u.number;
2119 }
2120 else
2121 {
2122 bprop->u.number |= features;
2123 updated = TRUE;
2124 }
2125 }
2126 else if (aprop != NULL)
2127 {
2128 aprop->pr_kind = property_remove;
2129 updated = TRUE;
2130 }
2131 }
2132 break;
2133
2134 default:
2135 /* Never should happen. */
2136 abort ();
2137 }
2138
2139 return updated;
2140 }
2141
2142 /* Set up x86 GNU properties. Return the first relocatable ELF input
2143 with GNU properties if found. Otherwise, return NULL. */
2144
2145 bfd *
2146 _bfd_x86_elf_link_setup_gnu_properties
2147 (struct bfd_link_info *info, struct elf_x86_init_table *init_table)
2148 {
2149 bfd_boolean normal_target;
2150 bfd_boolean lazy_plt;
2151 asection *sec, *pltsec;
2152 bfd *dynobj;
2153 bfd_boolean use_ibt_plt;
2154 unsigned int plt_alignment, features;
2155 struct elf_x86_link_hash_table *htab;
2156 bfd *pbfd;
2157 bfd *ebfd = NULL;
2158 elf_property *prop;
2159 const struct elf_backend_data *bed;
2160 unsigned int class_align = ABI_64_P (info->output_bfd) ? 3 : 2;
2161 unsigned int got_align;
2162
2163 features = 0;
2164 if (info->ibt)
2165 features = GNU_PROPERTY_X86_FEATURE_1_IBT;
2166 if (info->shstk)
2167 features |= GNU_PROPERTY_X86_FEATURE_1_SHSTK;
2168
2169 /* Find a normal input file with GNU property note. */
2170 for (pbfd = info->input_bfds;
2171 pbfd != NULL;
2172 pbfd = pbfd->link.next)
2173 if (bfd_get_flavour (pbfd) == bfd_target_elf_flavour
2174 && bfd_count_sections (pbfd) != 0)
2175 {
2176 ebfd = pbfd;
2177
2178 if (elf_properties (pbfd) != NULL)
2179 break;
2180 }
2181
2182 if (ebfd != NULL && features)
2183 {
2184 /* If features is set, add GNU_PROPERTY_X86_FEATURE_1_IBT and
2185 GNU_PROPERTY_X86_FEATURE_1_SHSTK. */
2186 prop = _bfd_elf_get_property (ebfd,
2187 GNU_PROPERTY_X86_FEATURE_1_AND,
2188 4);
2189 prop->u.number |= features;
2190 prop->pr_kind = property_number;
2191
2192 /* Create the GNU property note section if needed. */
2193 if (pbfd == NULL)
2194 {
2195 sec = bfd_make_section_with_flags (ebfd,
2196 NOTE_GNU_PROPERTY_SECTION_NAME,
2197 (SEC_ALLOC
2198 | SEC_LOAD
2199 | SEC_IN_MEMORY
2200 | SEC_READONLY
2201 | SEC_HAS_CONTENTS
2202 | SEC_DATA));
2203 if (sec == NULL)
2204 info->callbacks->einfo (_("%F: failed to create GNU property section\n"));
2205
2206 if (!bfd_set_section_alignment (ebfd, sec, class_align))
2207 {
2208 error_alignment:
2209 info->callbacks->einfo (_("%F%A: failed to align section\n"),
2210 sec);
2211 }
2212
2213 elf_section_type (sec) = SHT_NOTE;
2214 }
2215 }
2216
2217 pbfd = _bfd_elf_link_setup_gnu_properties (info);
2218
2219 bed = get_elf_backend_data (info->output_bfd);
2220
2221 htab = elf_x86_hash_table (info, bed->target_id);
2222 if (htab == NULL)
2223 return pbfd;
2224
2225 htab->is_vxworks = init_table->is_vxworks;
2226 htab->r_info = init_table->r_info;
2227 htab->r_sym = init_table->r_sym;
2228
2229 if (bfd_link_relocatable (info))
2230 return pbfd;
2231
2232 use_ibt_plt = info->ibtplt || info->ibt;
2233 if (!use_ibt_plt && pbfd != NULL)
2234 {
2235 /* Check if GNU_PROPERTY_X86_FEATURE_1_IBT is on. */
2236 elf_property_list *p;
2237
2238 /* The property list is sorted in order of type. */
2239 for (p = elf_properties (pbfd); p; p = p->next)
2240 {
2241 if (GNU_PROPERTY_X86_FEATURE_1_AND == p->property.pr_type)
2242 {
2243 use_ibt_plt = !!(p->property.u.number
2244 & GNU_PROPERTY_X86_FEATURE_1_IBT);
2245 break;
2246 }
2247 else if (GNU_PROPERTY_X86_FEATURE_1_AND < p->property.pr_type)
2248 break;
2249 }
2250 }
2251
2252 dynobj = htab->elf.dynobj;
2253
2254 /* Set htab->elf.dynobj here so that there is no need to check and
2255 set it in check_relocs. */
2256 if (dynobj == NULL)
2257 {
2258 if (pbfd != NULL)
2259 {
2260 htab->elf.dynobj = pbfd;
2261 dynobj = pbfd;
2262 }
2263 else
2264 {
2265 bfd *abfd;
2266
2267 /* Find a normal input file to hold linker created
2268 sections. */
2269 for (abfd = info->input_bfds;
2270 abfd != NULL;
2271 abfd = abfd->link.next)
2272 if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
2273 && (abfd->flags
2274 & (DYNAMIC | BFD_LINKER_CREATED | BFD_PLUGIN)) == 0)
2275 {
2276 htab->elf.dynobj = abfd;
2277 dynobj = abfd;
2278 break;
2279 }
2280 }
2281 }
2282
2283 /* Even when lazy binding is disabled by "-z now", the PLT0 entry may
2284 still be used with LD_AUDIT or LD_PROFILE if PLT entry is used for
2285 canonical function address. */
2286 htab->plt.has_plt0 = 1;
2287 normal_target = init_table->normal_target;
2288
2289 if (normal_target)
2290 {
2291 if (use_ibt_plt)
2292 {
2293 htab->lazy_plt = init_table->lazy_ibt_plt;
2294 htab->non_lazy_plt = init_table->non_lazy_ibt_plt;
2295 }
2296 else
2297 {
2298 htab->lazy_plt = init_table->lazy_plt;
2299 htab->non_lazy_plt = init_table->non_lazy_plt;
2300 }
2301 }
2302 else
2303 {
2304 htab->lazy_plt = init_table->lazy_plt;
2305 htab->non_lazy_plt = NULL;
2306 }
2307
2308 pltsec = htab->elf.splt;
2309
2310 /* If the non-lazy PLT is available, use it for all PLT entries if
2311 there are no PLT0 or no .plt section. */
2312 if (htab->non_lazy_plt != NULL
2313 && (!htab->plt.has_plt0 || pltsec == NULL))
2314 {
2315 lazy_plt = FALSE;
2316 if (bfd_link_pic (info))
2317 htab->plt.plt_entry = htab->non_lazy_plt->pic_plt_entry;
2318 else
2319 htab->plt.plt_entry = htab->non_lazy_plt->plt_entry;
2320 htab->plt.plt_entry_size = htab->non_lazy_plt->plt_entry_size;
2321 htab->plt.plt_got_offset = htab->non_lazy_plt->plt_got_offset;
2322 htab->plt.plt_got_insn_size
2323 = htab->non_lazy_plt->plt_got_insn_size;
2324 htab->plt.eh_frame_plt_size
2325 = htab->non_lazy_plt->eh_frame_plt_size;
2326 htab->plt.eh_frame_plt = htab->non_lazy_plt->eh_frame_plt;
2327 }
2328 else
2329 {
2330 lazy_plt = TRUE;
2331 if (bfd_link_pic (info))
2332 {
2333 htab->plt.plt0_entry = htab->lazy_plt->pic_plt0_entry;
2334 htab->plt.plt_entry = htab->lazy_plt->pic_plt_entry;
2335 }
2336 else
2337 {
2338 htab->plt.plt0_entry = htab->lazy_plt->plt0_entry;
2339 htab->plt.plt_entry = htab->lazy_plt->plt_entry;
2340 }
2341 htab->plt.plt_entry_size = htab->lazy_plt->plt_entry_size;
2342 htab->plt.plt_got_offset = htab->lazy_plt->plt_got_offset;
2343 htab->plt.plt_got_insn_size
2344 = htab->lazy_plt->plt_got_insn_size;
2345 htab->plt.eh_frame_plt_size
2346 = htab->lazy_plt->eh_frame_plt_size;
2347 htab->plt.eh_frame_plt = htab->lazy_plt->eh_frame_plt;
2348 }
2349
2350 /* Return if there are no normal input files. */
2351 if (dynobj == NULL)
2352 return pbfd;
2353
2354 if (htab->is_vxworks
2355 && !elf_vxworks_create_dynamic_sections (dynobj, info,
2356 &htab->srelplt2))
2357 {
2358 info->callbacks->einfo (_("%F: failed to create VxWorks dynamic sections\n"));
2359 return pbfd;
2360 }
2361
2362 /* Since create_dynamic_sections isn't always called, but GOT
2363 relocations need GOT relocations, create them here so that we
2364 don't need to do it in check_relocs. */
2365 if (htab->elf.sgot == NULL
2366 && !_bfd_elf_create_got_section (dynobj, info))
2367 info->callbacks->einfo (_("%F: failed to create GOT sections\n"));
2368
2369 got_align = (bed->target_id == X86_64_ELF_DATA) ? 3 : 2;
2370
2371 /* Align .got and .got.plt sections to their entry size. Do it here
2372 instead of in create_dynamic_sections so that they are always
2373 properly aligned even if create_dynamic_sections isn't called. */
2374 sec = htab->elf.sgot;
2375 if (!bfd_set_section_alignment (dynobj, sec, got_align))
2376 goto error_alignment;
2377
2378 sec = htab->elf.sgotplt;
2379 if (!bfd_set_section_alignment (dynobj, sec, got_align))
2380 goto error_alignment;
2381
2382 /* Create the ifunc sections here so that check_relocs can be
2383 simplified. */
2384 if (!_bfd_elf_create_ifunc_sections (dynobj, info))
2385 info->callbacks->einfo (_("%F: failed to create ifunc sections\n"));
2386
2387 plt_alignment = bfd_log2 (htab->plt.plt_entry_size);
2388
2389 if (pltsec != NULL)
2390 {
2391 /* Whe creating executable, set the contents of the .interp
2392 section to the interpreter. */
2393 if (bfd_link_executable (info) && !info->nointerp)
2394 {
2395 asection *s = bfd_get_linker_section (dynobj, ".interp");
2396 if (s == NULL)
2397 abort ();
2398 s->size = htab->dynamic_interpreter_size;
2399 s->contents = (unsigned char *) htab->dynamic_interpreter;
2400 htab->interp = s;
2401 }
2402
2403 /* Don't change PLT section alignment for NaCl since it uses
2404 64-byte PLT entry and sets PLT section alignment to 32
2405 bytes. Don't create additional PLT sections for NaCl. */
2406 if (normal_target)
2407 {
2408 flagword pltflags = (bed->dynamic_sec_flags
2409 | SEC_ALLOC
2410 | SEC_CODE
2411 | SEC_LOAD
2412 | SEC_READONLY);
2413 unsigned int non_lazy_plt_alignment
2414 = bfd_log2 (htab->non_lazy_plt->plt_entry_size);
2415
2416 sec = pltsec;
2417 if (!bfd_set_section_alignment (sec->owner, sec,
2418 plt_alignment))
2419 goto error_alignment;
2420
2421 /* Create the GOT procedure linkage table. */
2422 sec = bfd_make_section_anyway_with_flags (dynobj,
2423 ".plt.got",
2424 pltflags);
2425 if (sec == NULL)
2426 info->callbacks->einfo (_("%F: failed to create GOT PLT section\n"));
2427
2428 if (!bfd_set_section_alignment (dynobj, sec,
2429 non_lazy_plt_alignment))
2430 goto error_alignment;
2431
2432 htab->plt_got = sec;
2433
2434 if (lazy_plt)
2435 {
2436 sec = NULL;
2437
2438 if (use_ibt_plt)
2439 {
2440 /* Create the second PLT for Intel IBT support. IBT
2441 PLT is supported only for non-NaCl target and is
2442 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 IBT-enabled PLT section\n"));
2448
2449 if (!bfd_set_section_alignment (dynobj, sec,
2450 plt_alignment))
2451 goto error_alignment;
2452 }
2453 else if (info->bndplt && ABI_64_P (dynobj))
2454 {
2455 /* Create the second PLT for Intel MPX support. MPX
2456 PLT is supported only for non-NaCl target in 64-bit
2457 mode and is needed only for lazy binding. */
2458 sec = bfd_make_section_anyway_with_flags (dynobj,
2459 ".plt.sec",
2460 pltflags);
2461 if (sec == NULL)
2462 info->callbacks->einfo (_("%F: failed to create BND PLT section\n"));
2463
2464 if (!bfd_set_section_alignment (dynobj, sec,
2465 non_lazy_plt_alignment))
2466 goto error_alignment;
2467 }
2468
2469 htab->plt_second = sec;
2470 }
2471 }
2472
2473 if (!info->no_ld_generated_unwind_info)
2474 {
2475 flagword flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY
2476 | SEC_HAS_CONTENTS | SEC_IN_MEMORY
2477 | SEC_LINKER_CREATED);
2478
2479 sec = bfd_make_section_anyway_with_flags (dynobj,
2480 ".eh_frame",
2481 flags);
2482 if (sec == NULL)
2483 info->callbacks->einfo (_("%F: failed to create PLT .eh_frame section\n"));
2484
2485 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2486 goto error_alignment;
2487
2488 htab->plt_eh_frame = sec;
2489
2490 if (htab->plt_got != NULL)
2491 {
2492 sec = bfd_make_section_anyway_with_flags (dynobj,
2493 ".eh_frame",
2494 flags);
2495 if (sec == NULL)
2496 info->callbacks->einfo (_("%F: failed to create GOT PLT .eh_frame section\n"));
2497
2498 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2499 goto error_alignment;
2500
2501 htab->plt_got_eh_frame = sec;
2502 }
2503
2504 if (htab->plt_second != NULL)
2505 {
2506 sec = bfd_make_section_anyway_with_flags (dynobj,
2507 ".eh_frame",
2508 flags);
2509 if (sec == NULL)
2510 info->callbacks->einfo (_("%F: failed to create the second PLT .eh_frame section\n"));
2511
2512 if (!bfd_set_section_alignment (dynobj, sec, class_align))
2513 goto error_alignment;
2514
2515 htab->plt_second_eh_frame = sec;
2516 }
2517 }
2518 }
2519
2520 if (normal_target)
2521 {
2522 /* The .iplt section is used for IFUNC symbols in static
2523 executables. */
2524 sec = htab->elf.iplt;
2525 if (sec != NULL
2526 && !bfd_set_section_alignment (sec->owner, sec,
2527 plt_alignment))
2528 goto error_alignment;
2529 }
2530
2531 return pbfd;
2532 }
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