/* ELF STT_GNU_IFUNC support.
- Copyright 2009
- Free Software Foundation, Inc.
+ Copyright (C) 2009-2015 Free Software Foundation, Inc.
This file is part of BFD, the Binary File Descriptor library.
return TRUE;
}
-/* For a STT_GNU_IFUNC symbol, create a dynamic reloc section, SRELOC,
- for the input section, SEC, and append this reloc to HEAD. */
-
-asection *
-_bfd_elf_create_ifunc_dyn_reloc (bfd *abfd, struct bfd_link_info *info,
- asection *sec, asection *sreloc,
- struct elf_dyn_relocs **head)
-{
- struct elf_dyn_relocs *p;
- struct elf_link_hash_table *htab = elf_hash_table (info);
-
- if (sreloc == NULL)
- {
- const struct elf_backend_data *bed = get_elf_backend_data (abfd);
-
- if (htab->dynobj == NULL)
- htab->dynobj = abfd;
-
- sreloc = _bfd_elf_make_dynamic_reloc_section (sec, htab->dynobj,
- bed->s->log_file_align,
- abfd,
- bed->rela_plts_and_copies_p);
- if (sreloc == NULL)
- return NULL;
- }
-
- p = *head;
- if (p == NULL || p->sec != sec)
- {
- bfd_size_type amt = sizeof *p;
-
- p = ((struct elf_dyn_relocs *) bfd_alloc (htab->dynobj, amt));
- if (p == NULL)
- return NULL;
- p->next = *head;
- *head = p;
- p->sec = sec;
- p->count = 0;
- p->pc_count = 0;
- }
- p->count += 1;
-
- return sreloc;
-}
-
/* Allocate space in .plt, .got and associated reloc sections for
dynamic relocs against a STT_GNU_IFUNC symbol definition. */
struct elf_link_hash_entry *h,
struct elf_dyn_relocs **head,
unsigned int plt_entry_size,
+ unsigned int plt_header_size,
unsigned int got_entry_size)
{
asection *plt, *gotplt, *relplt;
|| info->export_dynamic)
&& h->pointer_equality_needed)
{
- info->callbacks->einfo
+ info->callbacks->einfo
(_("%F%P: dynamic STT_GNU_IFUNC symbol `%s' with pointer "
"equality in `%B' can not be used when making an "
"executable; recompile with -fPIE and relink with -pie\n"),
htab = elf_hash_table (info);
+ /* When building shared library, we need to handle the case where it is
+ marked with regular reference, but not non-GOT reference since the
+ non-GOT reference bit may not be set here. */
+ if (info->shared && !h->non_got_ref && h->ref_regular)
+ for (p = *head; p != NULL; p = p->next)
+ if (p->count)
+ {
+ h->non_got_ref = 1;
+ goto keep;
+ }
+
/* Support garbage collection against STT_GNU_IFUNC symbols. */
if (h->plt.refcount <= 0 && h->got.refcount <= 0)
{
- /* When building shared library, we need to handle the case
- where it is marked with regular reference, but not non-GOT
- reference. It may happen if we didn't see STT_GNU_IFUNC
- symbol at the time when checking relocations. */
- if (info->shared
- && !h->non_got_ref
- && h->ref_regular)
- for (p = *head; p != NULL; p = p->next)
- if (p->count)
- {
- h->non_got_ref = 1;
- goto keep;
- }
-
h->got = htab->init_got_offset;
h->plt = htab->init_plt_offset;
*head = NULL;
/* If this is the first .plt entry, make room for the special
first entry. */
if (plt->size == 0)
- plt->size += plt_entry_size;
+ plt->size += plt_header_size;
}
else
{
}
/* Don't update value of STT_GNU_IFUNC symbol to PLT. We need
- the original value for R_*_IRELATIVE. */
+ the original value for R_*_IRELATIVE. */
h->plt.offset = plt->size;
/* Make room for this entry in the .plt/.iplt section. */
return TRUE;
}
+
+/* Similar to _bfd_elf_get_synthetic_symtab, optimized for unsorted PLT
+ entries. PLT is the PLT section. PLT_SYM_VAL is a function pointer
+ which returns an array of PLT entry symbol values. */
+
+long
+_bfd_elf_ifunc_get_synthetic_symtab
+ (bfd *abfd, long symcount ATTRIBUTE_UNUSED,
+ asymbol **syms ATTRIBUTE_UNUSED, long dynsymcount, asymbol **dynsyms,
+ asymbol **ret, asection *plt,
+ bfd_vma *(*get_plt_sym_val) (bfd *, asymbol **, asection *, asection *))
+{
+ const struct elf_backend_data *bed = get_elf_backend_data (abfd);
+ asection *relplt;
+ asymbol *s;
+ const char *relplt_name;
+ bfd_boolean (*slurp_relocs) (bfd *, asection *, asymbol **, bfd_boolean);
+ arelent *p;
+ long count, i, n;
+ size_t size;
+ Elf_Internal_Shdr *hdr;
+ char *names;
+ bfd_vma *plt_sym_val;
+
+ *ret = NULL;
+
+ if (plt == NULL)
+ return 0;
+
+ if ((abfd->flags & (DYNAMIC | EXEC_P)) == 0)
+ return 0;
+
+ if (dynsymcount <= 0)
+ return 0;
+
+ relplt_name = bed->relplt_name;
+ if (relplt_name == NULL)
+ relplt_name = bed->rela_plts_and_copies_p ? ".rela.plt" : ".rel.plt";
+ relplt = bfd_get_section_by_name (abfd, relplt_name);
+ if (relplt == NULL)
+ return 0;
+
+ hdr = &elf_section_data (relplt)->this_hdr;
+ if (hdr->sh_link != elf_dynsymtab (abfd)
+ || (hdr->sh_type != SHT_REL && hdr->sh_type != SHT_RELA))
+ return 0;
+
+ slurp_relocs = get_elf_backend_data (abfd)->s->slurp_reloc_table;
+ if (! (*slurp_relocs) (abfd, relplt, dynsyms, TRUE))
+ return -1;
+
+ count = relplt->size / hdr->sh_entsize;
+ size = count * sizeof (asymbol);
+ p = relplt->relocation;
+ for (i = 0; i < count; i++, p += bed->s->int_rels_per_ext_rel)
+ {
+ size += strlen ((*p->sym_ptr_ptr)->name) + sizeof ("@plt");
+ if (p->addend != 0)
+ {
+#ifdef BFD64
+ size += sizeof ("+0x") - 1 + 8 + 8 * (bed->s->elfclass == ELFCLASS64);
+#else
+ size += sizeof ("+0x") - 1 + 8;
+#endif
+ }
+ }
+
+ plt_sym_val = get_plt_sym_val (abfd, dynsyms, plt, relplt);
+ if (plt_sym_val == NULL)
+ return -1;
+
+ s = *ret = (asymbol *) bfd_malloc (size);
+ if (s == NULL)
+ {
+ free (plt_sym_val);
+ return -1;
+ }
+
+ names = (char *) (s + count);
+ p = relplt->relocation;
+ n = 0;
+ for (i = 0; i < count; i++, p += bed->s->int_rels_per_ext_rel)
+ {
+ size_t len;
+ bfd_vma addr;
+
+ addr = plt_sym_val[i];
+ if (addr == (bfd_vma) -1)
+ continue;
+
+ *s = **p->sym_ptr_ptr;
+ /* Undefined syms won't have BSF_LOCAL or BSF_GLOBAL set. Since
+ we are defining a symbol, ensure one of them is set. */
+ if ((s->flags & BSF_LOCAL) == 0)
+ s->flags |= BSF_GLOBAL;
+ s->flags |= BSF_SYNTHETIC;
+ s->section = plt;
+ s->value = addr - plt->vma;
+ s->name = names;
+ s->udata.p = NULL;
+ len = strlen ((*p->sym_ptr_ptr)->name);
+ memcpy (names, (*p->sym_ptr_ptr)->name, len);
+ names += len;
+ if (p->addend != 0)
+ {
+ char buf[30], *a;
+
+ memcpy (names, "+0x", sizeof ("+0x") - 1);
+ names += sizeof ("+0x") - 1;
+ bfd_sprintf_vma (abfd, buf, p->addend);
+ for (a = buf; *a == '0'; ++a)
+ ;
+ len = strlen (a);
+ memcpy (names, a, len);
+ names += len;
+ }
+ memcpy (names, "@plt", sizeof ("@plt"));
+ names += sizeof ("@plt");
+ ++s, ++n;
+ }
+
+ free (plt_sym_val);
+
+ return n;
+}
projects / deliverable / binutils-gdb.git / blobdiff