diff options
Diffstat (limited to 'bfd/elf32-i386.c')
-rw-r--r-- | bfd/elf32-i386.c | 455 |
1 files changed, 3 insertions, 452 deletions
diff --git a/bfd/elf32-i386.c b/bfd/elf32-i386.c index bc2b219..2caff7f 100644 --- a/bfd/elf32-i386.c +++ b/bfd/elf32-i386.c @@ -1951,456 +1951,6 @@ error_return: return FALSE; } -/* Allocate space in .plt, .got and associated reloc sections for - dynamic relocs. */ - -static bfd_boolean -elf_i386_allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf) -{ - struct bfd_link_info *info; - struct elf_x86_link_hash_table *htab; - struct elf_x86_link_hash_entry *eh; - struct elf_dyn_relocs *p; - unsigned plt_entry_size; - bfd_boolean resolved_to_zero; - - if (h->root.type == bfd_link_hash_indirect) - return TRUE; - - eh = (struct elf_x86_link_hash_entry *) h; - - info = (struct bfd_link_info *) inf; - htab = elf_x86_hash_table (info, I386_ELF_DATA); - if (htab == NULL) - return FALSE; - - plt_entry_size = htab->plt.plt_entry_size; - - resolved_to_zero = UNDEFINED_WEAK_RESOLVED_TO_ZERO (info, - I386_ELF_DATA, - eh->has_got_reloc, - eh); - - /* Clear the reference count of function pointer relocations if - symbol isn't a normal function. */ - if (h->type != STT_FUNC) - eh->func_pointer_refcount = 0; - - /* We can't use the GOT PLT if pointer equality is needed since - finish_dynamic_symbol won't clear symbol value and the dynamic - linker won't update the GOT slot. We will get into an infinite - loop at run-time. */ - if (htab->plt_got != NULL - && h->type != STT_GNU_IFUNC - && !h->pointer_equality_needed - && h->plt.refcount > 0 - && h->got.refcount > 0) - { - /* Don't use the regular PLT if there are both GOT and GOTPLT - reloctions. */ - h->plt.offset = (bfd_vma) -1; - - /* Use the GOT PLT. */ - eh->plt_got.refcount = 1; - } - - /* Since STT_GNU_IFUNC symbol must go through PLT, we handle it - here if it is defined and referenced in a non-shared object. */ - if (h->type == STT_GNU_IFUNC - && h->def_regular) - { - if (_bfd_elf_allocate_ifunc_dyn_relocs (info, h, &eh->dyn_relocs, - &htab->readonly_dynrelocs_against_ifunc, - plt_entry_size, - (htab->plt.has_plt0 - * plt_entry_size), - 4, TRUE)) - { - asection *s = htab->plt_second; - if (h->plt.offset != (bfd_vma) -1 && s != NULL) - { - /* Use the second PLT section if it is created. */ - eh->plt_second.offset = s->size; - - /* Make room for this entry in the second PLT section. */ - s->size += htab->non_lazy_plt->plt_entry_size; - } - - return TRUE; - } - else - return FALSE; - } - /* Don't create the PLT entry if there are only function pointer - relocations which can be resolved at run-time. */ - else if (htab->elf.dynamic_sections_created - && (h->plt.refcount > eh->func_pointer_refcount - || eh->plt_got.refcount > 0)) - { - bfd_boolean use_plt_got = eh->plt_got.refcount > 0; - - /* Clear the reference count of function pointer relocations - if PLT is used. */ - eh->func_pointer_refcount = 0; - - /* Make sure this symbol is output as a dynamic symbol. - Undefined weak syms won't yet be marked as dynamic. */ - if (h->dynindx == -1 - && !h->forced_local - && !resolved_to_zero - && h->root.type == bfd_link_hash_undefweak) - { - if (! bfd_elf_link_record_dynamic_symbol (info, h)) - return FALSE; - } - - if (bfd_link_pic (info) - || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h)) - { - asection *s = htab->elf.splt; - asection *second_s = htab->plt_second; - asection *got_s = htab->plt_got; - - /* If this is the first .plt entry, make room for the special - first entry. The .plt section is used by prelink to undo - prelinking for dynamic relocations. */ - if (s->size == 0) - s->size = htab->plt.has_plt0 * plt_entry_size; - - if (use_plt_got) - eh->plt_got.offset = got_s->size; - else - { - h->plt.offset = s->size; - if (second_s) - eh->plt_second.offset = second_s->size; - } - - /* If this symbol is not defined in a regular file, and we are - not generating a shared library, then set the symbol to this - location in the .plt. This is required to make function - pointers compare as equal between the normal executable and - the shared library. */ - if (! bfd_link_pic (info) - && !h->def_regular) - { - if (use_plt_got) - { - /* We need to make a call to the entry of the GOT PLT - instead of regular PLT entry. */ - h->root.u.def.section = got_s; - h->root.u.def.value = eh->plt_got.offset; - } - else - { - if (second_s) - { - /* We need to make a call to the entry of the - second PLT instead of regular PLT entry. */ - h->root.u.def.section = second_s; - h->root.u.def.value = eh->plt_second.offset; - } - else - { - h->root.u.def.section = s; - h->root.u.def.value = h->plt.offset; - } - } - } - - /* Make room for this entry. */ - if (use_plt_got) - got_s->size += htab->non_lazy_plt->plt_entry_size; - else - { - s->size += plt_entry_size; - if (second_s) - second_s->size += htab->non_lazy_plt->plt_entry_size; - - /* We also need to make an entry in the .got.plt section, - which will be placed in the .got section by the linker - script. */ - htab->elf.sgotplt->size += 4; - - /* There should be no PLT relocation against resolved - undefined weak symbol in executable. */ - if (!resolved_to_zero) - { - /* We also need to make an entry in the .rel.plt - section. */ - htab->elf.srelplt->size += sizeof (Elf32_External_Rel); - htab->elf.srelplt->reloc_count++; - } - } - - if (htab->is_vxworks && !bfd_link_pic (info)) - { - /* VxWorks has a second set of relocations for each PLT entry - in executables. They go in a separate relocation section, - which is processed by the kernel loader. */ - - /* There are two relocations for the initial PLT entry: an - R_386_32 relocation for _GLOBAL_OFFSET_TABLE_ + 4 and an - R_386_32 relocation for _GLOBAL_OFFSET_TABLE_ + 8. */ - - asection *srelplt2 = htab->srelplt2; - if (h->plt.offset == plt_entry_size) - srelplt2->size += (sizeof (Elf32_External_Rel) * 2); - - /* There are two extra relocations for each subsequent PLT entry: - an R_386_32 relocation for the GOT entry, and an R_386_32 - relocation for the PLT entry. */ - - srelplt2->size += (sizeof (Elf32_External_Rel) * 2); - } - } - else - { - eh->plt_got.offset = (bfd_vma) -1; - h->plt.offset = (bfd_vma) -1; - h->needs_plt = 0; - } - } - else - { - eh->plt_got.offset = (bfd_vma) -1; - h->plt.offset = (bfd_vma) -1; - h->needs_plt = 0; - } - - eh->tlsdesc_got = (bfd_vma) -1; - - /* If R_386_TLS_{IE_32,IE,GOTIE} symbol is now local to the binary, - make it a R_386_TLS_LE_32 requiring no TLS entry. */ - if (h->got.refcount > 0 - && bfd_link_executable (info) - && h->dynindx == -1 - && (elf_x86_hash_entry (h)->tls_type & GOT_TLS_IE)) - h->got.offset = (bfd_vma) -1; - else if (h->got.refcount > 0) - { - asection *s; - bfd_boolean dyn; - int tls_type = elf_x86_hash_entry (h)->tls_type; - - /* Make sure this symbol is output as a dynamic symbol. - Undefined weak syms won't yet be marked as dynamic. */ - if (h->dynindx == -1 - && !h->forced_local - && !resolved_to_zero - && h->root.type == bfd_link_hash_undefweak) - { - if (! bfd_elf_link_record_dynamic_symbol (info, h)) - return FALSE; - } - - s = htab->elf.sgot; - if (GOT_TLS_GDESC_P (tls_type)) - { - eh->tlsdesc_got = htab->elf.sgotplt->size - - elf_x86_compute_jump_table_size (htab); - htab->elf.sgotplt->size += 8; - h->got.offset = (bfd_vma) -2; - } - if (! GOT_TLS_GDESC_P (tls_type) - || GOT_TLS_GD_P (tls_type)) - { - h->got.offset = s->size; - s->size += 4; - /* R_386_TLS_GD needs 2 consecutive GOT slots. */ - if (GOT_TLS_GD_P (tls_type) || tls_type == GOT_TLS_IE_BOTH) - s->size += 4; - } - dyn = htab->elf.dynamic_sections_created; - /* R_386_TLS_IE_32 needs one dynamic relocation, - R_386_TLS_IE resp. R_386_TLS_GOTIE needs one dynamic relocation, - (but if both R_386_TLS_IE_32 and R_386_TLS_IE is present, we - need two), R_386_TLS_GD needs one if local symbol and two if - global. No dynamic relocation against resolved undefined weak - symbol in executable. */ - if (tls_type == GOT_TLS_IE_BOTH) - htab->elf.srelgot->size += 2 * sizeof (Elf32_External_Rel); - else if ((GOT_TLS_GD_P (tls_type) && h->dynindx == -1) - || (tls_type & GOT_TLS_IE)) - htab->elf.srelgot->size += sizeof (Elf32_External_Rel); - else if (GOT_TLS_GD_P (tls_type)) - htab->elf.srelgot->size += 2 * sizeof (Elf32_External_Rel); - else if (! GOT_TLS_GDESC_P (tls_type) - && ((ELF_ST_VISIBILITY (h->other) == STV_DEFAULT - && !resolved_to_zero) - || h->root.type != bfd_link_hash_undefweak) - && (bfd_link_pic (info) - || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h))) - htab->elf.srelgot->size += sizeof (Elf32_External_Rel); - if (GOT_TLS_GDESC_P (tls_type)) - htab->elf.srelplt->size += sizeof (Elf32_External_Rel); - } - else - h->got.offset = (bfd_vma) -1; - - if (eh->dyn_relocs == NULL) - return TRUE; - - /* In the shared -Bsymbolic case, discard space allocated for - dynamic pc-relative relocs against symbols which turn out to be - defined in regular objects. For the normal shared case, discard - space for pc-relative relocs that have become local due to symbol - visibility changes. */ - - if (bfd_link_pic (info)) - { - /* The only reloc that uses pc_count is R_386_PC32, which will - appear on a call or on something like ".long foo - .". We - want calls to protected symbols to resolve directly to the - function rather than going via the plt. If people want - function pointer comparisons to work as expected then they - should avoid writing assembly like ".long foo - .". */ - if (SYMBOL_CALLS_LOCAL (info, h)) - { - struct elf_dyn_relocs **pp; - - for (pp = &eh->dyn_relocs; (p = *pp) != NULL; ) - { - p->count -= p->pc_count; - p->pc_count = 0; - if (p->count == 0) - *pp = p->next; - else - pp = &p->next; - } - } - - if (htab->is_vxworks) - { - struct elf_dyn_relocs **pp; - for (pp = &eh->dyn_relocs; (p = *pp) != NULL; ) - { - if (strcmp (p->sec->output_section->name, ".tls_vars") == 0) - *pp = p->next; - else - pp = &p->next; - } - } - - /* Also discard relocs on undefined weak syms with non-default - visibility or in PIE. */ - if (eh->dyn_relocs != NULL - && h->root.type == bfd_link_hash_undefweak) - { - /* Undefined weak symbol is never bound locally in shared - library. */ - if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT - || resolved_to_zero) - { - if (h->non_got_ref) - { - /* Keep dynamic non-GOT/non-PLT relocation so that we - can branch to 0 without PLT. */ - struct elf_dyn_relocs **pp; - - for (pp = &eh->dyn_relocs; (p = *pp) != NULL; ) - if (p->pc_count == 0) - *pp = p->next; - else - { - /* Remove non-R_386_PC32 relocation. */ - p->count = p->pc_count; - pp = &p->next; - } - - if (eh->dyn_relocs != NULL) - { - /* Make sure undefined weak symbols are output - as dynamic symbols in PIEs for dynamic non-GOT - non-PLT reloations. */ - if (! bfd_elf_link_record_dynamic_symbol (info, h)) - return FALSE; - } - } - else - eh->dyn_relocs = NULL; - } - else if (h->dynindx == -1 - && !h->forced_local) - { - if (! bfd_elf_link_record_dynamic_symbol (info, h)) - return FALSE; - } - } - } - else if (ELIMINATE_COPY_RELOCS) - { - /* For the non-shared case, discard space for relocs against - symbols which turn out to need copy relocs or are not - dynamic. Keep dynamic relocations for run-time function - pointer initialization. */ - - if ((!h->non_got_ref - || eh->func_pointer_refcount > 0 - || (h->root.type == bfd_link_hash_undefweak - && !resolved_to_zero)) - && ((h->def_dynamic - && !h->def_regular) - || (htab->elf.dynamic_sections_created - && (h->root.type == bfd_link_hash_undefweak - || h->root.type == bfd_link_hash_undefined)))) - { - /* Make sure this symbol is output as a dynamic symbol. - Undefined weak syms won't yet be marked as dynamic. */ - if (h->dynindx == -1 - && !h->forced_local - && !resolved_to_zero - && h->root.type == bfd_link_hash_undefweak) - { - if (! bfd_elf_link_record_dynamic_symbol (info, h)) - return FALSE; - } - - /* If that succeeded, we know we'll be keeping all the - relocs. */ - if (h->dynindx != -1) - goto keep; - } - - eh->dyn_relocs = NULL; - eh->func_pointer_refcount = 0; - - keep: ; - } - - /* Finally, allocate space. */ - for (p = eh->dyn_relocs; p != NULL; p = p->next) - { - asection *sreloc; - - sreloc = elf_section_data (p->sec)->sreloc; - - BFD_ASSERT (sreloc != NULL); - sreloc->size += p->count * sizeof (Elf32_External_Rel); - } - - return TRUE; -} - -/* Allocate space in .plt, .got and associated reloc sections for - local dynamic relocs. */ - -static bfd_boolean -elf_i386_allocate_local_dynrelocs (void **slot, void *inf) -{ - struct elf_link_hash_entry *h - = (struct elf_link_hash_entry *) *slot; - - if (h->type != STT_GNU_IFUNC - || !h->def_regular - || !h->ref_regular - || !h->forced_local - || h->root.type != bfd_link_hash_defined) - abort (); - - return elf_i386_allocate_dynrelocs (h, inf); -} - /* Convert load via the GOT slot to load immediate. */ static bfd_boolean @@ -2673,11 +2223,12 @@ elf_i386_size_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info) /* Allocate global sym .plt and .got entries, and space for global sym dynamic relocs. */ - elf_link_hash_traverse (&htab->elf, elf_i386_allocate_dynrelocs, info); + elf_link_hash_traverse (&htab->elf, _bfd_x86_elf_allocate_dynrelocs, + info); /* Allocate .plt and .got entries, and space for local symbols. */ htab_traverse (htab->loc_hash_table, - elf_i386_allocate_local_dynrelocs, + _bfd_x86_elf_allocate_local_dynrelocs, info); /* For every jump slot reserved in the sgotplt, reloc_count is |