/* Intel 80386/80486-specific support for 32-bit ELF
- Copyright 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002,
- 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013
- Free Software Foundation, Inc.
+ Copyright (C) 1993-2014 Free Software Foundation, Inc.
This file is part of BFD, the Binary File Descriptor library.
abfd, (int) r_type);
indx = R_386_NONE;
}
- BFD_ASSERT (elf_howto_table [indx].type == r_type);
+ /* PR 17512: file: 0f67f69d. */
+ if (elf_howto_table [indx].type != r_type)
+ return NULL;
return &elf_howto_table[indx];
}
0, 0, 0, 0 /* replaced with offset to start of .plt. */
};
+/* Entries in the GOT procedure linkage table look like this. */
+
+static const bfd_byte elf_i386_got_plt_entry[8] =
+{
+ 0xff, 0x25, /* jmp indirect */
+ 0, 0, 0, 0, /* replaced with offset of this symbol in .got. */
+ 0x66, 0x90 /* xchg %ax,%ax */
+};
+
+/* Entries in the PIC GOT procedure linkage table look like this. */
+
+static const bfd_byte elf_i386_pic_got_plt_entry[8] =
+{
+ 0xff, 0xa3, /* jmp *offset(%ebx) */
+ 0, 0, 0, 0, /* replaced with offset of this symbol in .got. */
+ 0x66, 0x90 /* xchg %ax,%ax */
+};
+
/* .eh_frame covering the .plt section. */
static const bfd_byte elf_i386_eh_frame_plt[] =
(GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type))
unsigned char tls_type;
+ /* Information about the GOT PLT entry. Filled when there are both
+ GOT and PLT relocations against the same function. */
+ union gotplt_union plt_got;
+
/* Offset of the GOTPLT entry reserved for the TLS descriptor,
starting at the end of the jump table. */
bfd_vma tlsdesc_got;
asection *sdynbss;
asection *srelbss;
asection *plt_eh_frame;
+ asection *plt_got;
union
{
== I386_ELF_DATA ? ((struct elf_i386_link_hash_table *) ((p)->hash)) : NULL)
#define elf_i386_compute_jump_table_size(htab) \
- ((htab)->next_tls_desc_index * 4)
+ ((htab)->elf.srelplt->reloc_count * 4)
/* Create an entry in an i386 ELF linker hash table. */
eh = (struct elf_i386_link_hash_entry *) entry;
eh->dyn_relocs = NULL;
eh->tls_type = GOT_UNKNOWN;
+ eh->plt_got.offset = (bfd_vma) -1;
eh->tlsdesc_got = (bfd_vma) -1;
}
ret->elf.indx = sec->id;
ret->elf.dynstr_index = ELF32_R_SYM (rel->r_info);
ret->elf.dynindx = -1;
+ ret->plt_got.offset = (bfd_vma) -1;
*slot = ret;
}
return &ret->elf;
}
+/* Destroy an i386 ELF linker hash table. */
+
+static void
+elf_i386_link_hash_table_free (bfd *obfd)
+{
+ struct elf_i386_link_hash_table *htab
+ = (struct elf_i386_link_hash_table *) obfd->link.hash;
+
+ if (htab->loc_hash_table)
+ htab_delete (htab->loc_hash_table);
+ if (htab->loc_hash_memory)
+ objalloc_free ((struct objalloc *) htab->loc_hash_memory);
+ _bfd_elf_link_hash_table_free (obfd);
+}
+
/* Create an i386 ELF linker hash table. */
static struct bfd_link_hash_table *
ret->loc_hash_memory = objalloc_create ();
if (!ret->loc_hash_table || !ret->loc_hash_memory)
{
- free (ret);
+ elf_i386_link_hash_table_free (abfd);
return NULL;
}
+ ret->elf.root.hash_table_free = elf_i386_link_hash_table_free;
return &ret->elf.root;
}
-/* Destroy an i386 ELF linker hash table. */
-
-static void
-elf_i386_link_hash_table_free (struct bfd_link_hash_table *hash)
-{
- struct elf_i386_link_hash_table *htab
- = (struct elf_i386_link_hash_table *) hash;
-
- if (htab->loc_hash_table)
- htab_delete (htab->loc_hash_table);
- if (htab->loc_hash_memory)
- objalloc_free ((struct objalloc *) htab->loc_hash_memory);
- _bfd_elf_link_hash_table_free (hash);
-}
-
/* Create .plt, .rel.plt, .got, .got.plt, .rel.got, .dynbss, and
.rel.bss sections in DYNOBJ, and set up shortcuts to them in our
hash table. */
const Elf_Internal_Rela *rel;
const Elf_Internal_Rela *rel_end;
asection *sreloc;
+ bfd_boolean use_plt_got;
if (info->relocatable)
return TRUE;
if (htab == NULL)
return FALSE;
+ use_plt_got = (!get_elf_i386_backend_data (abfd)->is_vxworks
+ && (get_elf_i386_backend_data (abfd)
+ == &elf_i386_arch_bed));
+
symtab_hdr = &elf_symtab_hdr (abfd);
sym_hashes = elf_sym_hashes (abfd);
default:
break;
}
+
+ if (use_plt_got
+ && h != NULL
+ && h->plt.refcount > 0
+ && h->got.refcount > 0
+ && htab->plt_got == NULL)
+ {
+ /* Create the GOT procedure linkage table. */
+ unsigned int plt_got_align;
+ const struct elf_backend_data *bed;
+
+ bed = get_elf_backend_data (info->output_bfd);
+ BFD_ASSERT (sizeof (elf_i386_got_plt_entry) == 8
+ && (sizeof (elf_i386_got_plt_entry)
+ == sizeof (elf_i386_pic_got_plt_entry)));
+ plt_got_align = 3;
+
+ if (htab->elf.dynobj == NULL)
+ htab->elf.dynobj = abfd;
+ htab->plt_got
+ = bfd_make_section_anyway_with_flags (htab->elf.dynobj,
+ ".plt.got",
+ (bed->dynamic_sec_flags
+ | SEC_ALLOC
+ | SEC_CODE
+ | SEC_LOAD
+ | SEC_READONLY));
+ if (htab->plt_got == NULL
+ || !bfd_set_section_alignment (htab->elf.dynobj,
+ htab->plt_got,
+ plt_got_align))
+ return FALSE;
+ }
}
return TRUE;
plt_entry_size = GET_PLT_ENTRY_SIZE (info->output_bfd);
+ /* 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
plt_entry_size,
plt_entry_size, 4);
else if (htab->elf.dynamic_sections_created
- && h->plt.refcount > 0)
+ && (h->plt.refcount > 0 || eh->plt_got.refcount > 0))
{
+ bfd_boolean use_plt_got = eh->plt_got.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
|| WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h))
{
asection *s = htab->elf.splt;
+ asection *got_s = htab->plt_got;
/* If this is the first .plt entry, make room for the special
first entry. */
if (s->size == 0)
s->size = plt_entry_size;
- h->plt.offset = s->size;
+ if (use_plt_got)
+ eh->plt_got.offset = got_s->size;
+ else
+ h->plt.offset = 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
if (! info->shared
&& !h->def_regular)
{
- h->root.u.def.section = s;
- h->root.u.def.value = h->plt.offset;
+ 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
+ {
+ h->root.u.def.section = s;
+ h->root.u.def.value = h->plt.offset;
+ }
}
/* Make room for this entry. */
- s->size += plt_entry_size;
+ if (use_plt_got)
+ got_s->size += sizeof (elf_i386_got_plt_entry);
+ else
+ {
+ s->size += 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;
+ /* 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;
- /* 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++;
+ /* 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 (get_elf_i386_backend_data (info->output_bfd)->is_vxworks
&& !info->shared)
}
/* Also discard relocs on undefined weak syms with non-default
- visibility. Don't discard relocs against __ehdr_start which
- will be defined by assign_file_positions_for_non_load_sections
- later. */
+ visibility. */
if (eh->dyn_relocs != NULL
- && h->root.type == bfd_link_hash_undefweak
- && strcmp (h->root.root.string, "__ehdr_start") != 0)
+ && h->root.type == bfd_link_hash_undefweak)
{
if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
eh->dyn_relocs = NULL;
/* Nothing to do if there are no codes, no relocations or no output. */
if ((sec->flags & (SEC_CODE | SEC_RELOC)) != (SEC_CODE | SEC_RELOC)
|| sec->reloc_count == 0
- || discarded_section (sec))
+ || bfd_is_abs_section (sec->output_section))
return TRUE;
symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
/* STT_GNU_IFUNC must keep R_386_GOT32 relocation. */
if (ELF_ST_TYPE (isym->st_info) != STT_GNU_IFUNC
+ && irel->r_offset >= 2
&& bfd_get_8 (input_bfd,
contents + irel->r_offset - 2) == 0x8b)
{
&& h->type != STT_GNU_IFUNC
&& h != htab->elf.hdynamic
&& SYMBOL_REFERENCES_LOCAL (link_info, h)
+ && irel->r_offset >= 2
&& bfd_get_8 (input_bfd,
contents + irel->r_offset - 2) == 0x8b)
{
/* Set up .got offsets for local syms, and space for local dynamic
relocs. */
- for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
+ for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
{
bfd_signed_vma *local_got;
bfd_signed_vma *end_local_got;
else if (s == htab->elf.sgotplt
|| s == htab->elf.iplt
|| s == htab->elf.igotplt
+ || s == htab->plt_got
|| s == htab->plt_eh_frame
|| s == htab->sdynbss)
{
reloc_howto_type *howto;
unsigned long r_symndx;
struct elf_link_hash_entry *h;
+ struct elf_i386_link_hash_entry *eh;
Elf_Internal_Sym *sym;
asection *sec;
- bfd_vma off, offplt;
+ bfd_vma off, offplt, plt_offset;
bfd_vma relocation;
bfd_boolean unresolved_reloc;
bfd_reloc_status_type r;
unsigned int indx;
int tls_type;
bfd_vma st_size;
+ asection *resolved_plt;
r_type = ELF32_R_TYPE (rel->r_info);
if (r_type == R_386_GNU_VTINHERIT
if (h == NULL)
break;
- if (h->plt.offset == (bfd_vma) -1
+ eh = (struct elf_i386_link_hash_entry *) h;
+ if ((h->plt.offset == (bfd_vma) -1
+ && eh->plt_got.offset == (bfd_vma) -1)
|| htab->elf.splt == NULL)
{
/* We didn't make a PLT entry for this symbol. This
break;
}
- relocation = (htab->elf.splt->output_section->vma
- + htab->elf.splt->output_offset
- + h->plt.offset);
+ if (h->plt.offset != (bfd_vma) -1)
+ {
+ resolved_plt = htab->elf.splt;
+ plt_offset = h->plt.offset;
+ }
+ else
+ {
+ resolved_plt = htab->plt_got;
+ plt_offset = eh->plt_got.offset;
+ }
+
+ relocation = (resolved_plt->output_section->vma
+ + resolved_plt->output_offset
+ + plt_offset);
unresolved_reloc = FALSE;
break;
struct elf_i386_link_hash_table *htab;
unsigned plt_entry_size;
const struct elf_i386_backend_data *abed;
+ struct elf_i386_link_hash_entry *eh;
htab = elf_i386_hash_table (info);
if (htab == NULL)
abed = get_elf_i386_backend_data (output_bfd);
plt_entry_size = GET_PLT_ENTRY_SIZE (output_bfd);
+ eh = (struct elf_i386_link_hash_entry *) h;
+
if (h->plt.offset != (bfd_vma) -1)
{
bfd_vma plt_index;
plt->contents + h->plt.offset
+ abed->plt->plt_plt_offset);
}
+ }
+ else if (eh->plt_got.offset != (bfd_vma) -1)
+ {
+ bfd_vma got_offset, plt_offset;
+ asection *plt, *got, *gotplt;
+ const bfd_byte *got_plt_entry;
+
+ /* Offset of displacement of the indirect jump. */
+ bfd_vma plt_got_offset = 2;
+
+ /* Set the entry in the GOT procedure linkage table. */
+ plt = htab->plt_got;
+ got = htab->elf.sgot;
+ gotplt = htab->elf.sgotplt;
+ got_offset = h->got.offset;
+
+ if (got_offset == (bfd_vma) -1
+ || plt == NULL
+ || got == NULL
+ || gotplt == NULL)
+ abort ();
- if (!h->def_regular)
+ /* Fill in the entry in the GOT procedure linkage table. */
+ if (! info->shared)
+ {
+ got_plt_entry = elf_i386_got_plt_entry;
+ got_offset += got->output_section->vma + got->output_offset;
+ }
+ else
{
- /* Mark the symbol as undefined, rather than as defined in
- the .plt section. Leave the value if there were any
- relocations where pointer equality matters (this is a clue
- for the dynamic linker, to make function pointer
- comparisons work between an application and shared
- library), otherwise set it to zero. If a function is only
- called from a binary, there is no need to slow down
- shared libraries because of that. */
- sym->st_shndx = SHN_UNDEF;
- if (!h->pointer_equality_needed)
- sym->st_value = 0;
+ got_plt_entry = elf_i386_pic_got_plt_entry;
+ got_offset += (got->output_section->vma
+ + got->output_offset
+ - gotplt->output_section->vma
+ - gotplt->output_offset);
}
+
+ plt_offset = eh->plt_got.offset;
+ memcpy (plt->contents + plt_offset, got_plt_entry,
+ sizeof (elf_i386_got_plt_entry));
+ bfd_put_32 (output_bfd, got_offset,
+ plt->contents + plt_offset + plt_got_offset);
+ }
+
+ if (!h->def_regular
+ && (h->plt.offset != (bfd_vma) -1
+ || eh->plt_got.offset != (bfd_vma) -1))
+ {
+ /* Mark the symbol as undefined, rather than as defined in
+ the .plt section. Leave the value if there were any
+ relocations where pointer equality matters (this is a clue
+ for the dynamic linker, to make function pointer
+ comparisons work between an application and shared
+ library), otherwise set it to zero. If a function is only
+ called from a binary, there is no need to slow down
+ shared libraries because of that. */
+ sym->st_shndx = SHN_UNDEF;
+ if (!h->pointer_equality_needed)
+ sym->st_value = 0;
}
if (h->got.offset != (bfd_vma) -1
return TRUE;
}
-/* Return address for Ith PLT stub in section PLT, for relocation REL
- or (bfd_vma) -1 if it should not be included. */
+/* Return address in section PLT for the Ith GOTPLT relocation, for
+ relocation REL or (bfd_vma) -1 if it should not be included. */
static bfd_vma
-elf_i386_plt_sym_val (bfd_vma i, const asection *plt,
- const arelent *rel ATTRIBUTE_UNUSED)
+elf_i386_plt_sym_val (bfd_vma i, const asection *plt, const arelent *rel)
{
- return plt->vma + (i + 1) * GET_PLT_ENTRY_SIZE (plt->owner);
+ bfd *abfd;
+ const struct elf_i386_backend_data *bed;
+ bfd_vma plt_offset;
+
+ /* Only match R_386_JUMP_SLOT and R_386_IRELATIVE. */
+ if (rel->howto->type != R_386_JUMP_SLOT
+ && rel->howto->type != R_386_IRELATIVE)
+ return (bfd_vma) -1;
+
+ abfd = plt->owner;
+ bed = get_elf_i386_backend_data (abfd);
+ plt_offset = bed->plt->plt_entry_size;
+
+ if (elf_elfheader (abfd)->e_ident[EI_OSABI] != ELFOSABI_GNU)
+ return plt->vma + (i + 1) * plt_offset;
+
+ while (plt_offset < plt->size)
+ {
+ bfd_vma reloc_offset;
+ bfd_byte reloc_offset_raw[4];
+
+ if (!bfd_get_section_contents (abfd, (asection *) plt,
+ reloc_offset_raw,
+ plt_offset + bed->plt->plt_reloc_offset,
+ sizeof (reloc_offset_raw)))
+ return (bfd_vma) -1;
+
+ reloc_offset = H_GET_32 (abfd, reloc_offset_raw);
+ if (reloc_offset == i * sizeof (Elf32_External_Rel))
+ return plt->vma + plt_offset;
+ plt_offset += bed->plt->plt_entry_size;
+ }
+
+ abort ();
}
/* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */
static bfd_boolean
elf_i386_add_symbol_hook (bfd * abfd,
- struct bfd_link_info * info ATTRIBUTE_UNUSED,
+ struct bfd_link_info * info,
Elf_Internal_Sym * sym,
const char ** namep ATTRIBUTE_UNUSED,
flagword * flagsp ATTRIBUTE_UNUSED,
asection ** secp ATTRIBUTE_UNUSED,
bfd_vma * valp ATTRIBUTE_UNUSED)
{
- if ((abfd->flags & DYNAMIC) == 0
- && (ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC
- || ELF_ST_BIND (sym->st_info) == STB_GNU_UNIQUE))
+ if ((ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC
+ || ELF_ST_BIND (sym->st_info) == STB_GNU_UNIQUE)
+ && (abfd->flags & DYNAMIC) == 0
+ && bfd_get_flavour (info->output_bfd) == bfd_target_elf_flavour)
elf_tdata (info->output_bfd)->has_gnu_symbols = TRUE;
return TRUE;
}
-#define TARGET_LITTLE_SYM bfd_elf32_i386_vec
+#define TARGET_LITTLE_SYM i386_elf32_vec
#define TARGET_LITTLE_NAME "elf32-i386"
#define ELF_ARCH bfd_arch_i386
#define ELF_TARGET_ID I386_ELF_DATA
#define bfd_elf32_bfd_is_local_label_name elf_i386_is_local_label_name
#define bfd_elf32_bfd_link_hash_table_create elf_i386_link_hash_table_create
-#define bfd_elf32_bfd_link_hash_table_free elf_i386_link_hash_table_free
#define bfd_elf32_bfd_reloc_type_lookup elf_i386_reloc_type_lookup
#define bfd_elf32_bfd_reloc_name_lookup elf_i386_reloc_name_lookup
/* FreeBSD support. */
#undef TARGET_LITTLE_SYM
-#define TARGET_LITTLE_SYM bfd_elf32_i386_freebsd_vec
+#define TARGET_LITTLE_SYM i386_elf32_fbsd_vec
#undef TARGET_LITTLE_NAME
#define TARGET_LITTLE_NAME "elf32-i386-freebsd"
#undef ELF_OSABI
_bfd_elf_post_process_headers (abfd, info);
#ifdef OLD_FREEBSD_ABI_LABEL
- /* The ABI label supported by FreeBSD <= 4.0 is quite nonstandard. */
- memcpy (&i_ehdrp->e_ident[EI_ABIVERSION], "FreeBSD", 8);
+ {
+ /* The ABI label supported by FreeBSD <= 4.0 is quite nonstandard. */
+ Elf_Internal_Ehdr *i_ehdrp = elf_elfheader (abfd);
+ memcpy (&i_ehdrp->e_ident[EI_ABIVERSION], "FreeBSD", 8);
+ }
#endif
}
/* Solaris 2. */
#undef TARGET_LITTLE_SYM
-#define TARGET_LITTLE_SYM bfd_elf32_i386_sol2_vec
+#define TARGET_LITTLE_SYM i386_elf32_sol2_vec
#undef TARGET_LITTLE_NAME
#define TARGET_LITTLE_NAME "elf32-i386-sol2"
/* Native Client support. */
#undef TARGET_LITTLE_SYM
-#define TARGET_LITTLE_SYM bfd_elf32_i386_nacl_vec
+#define TARGET_LITTLE_SYM i386_elf32_nacl_vec
#undef TARGET_LITTLE_NAME
#define TARGET_LITTLE_NAME "elf32-i386-nacl"
#undef elf32_bed
/* VxWorks support. */
#undef TARGET_LITTLE_SYM
-#define TARGET_LITTLE_SYM bfd_elf32_i386_vxworks_vec
+#define TARGET_LITTLE_SYM i386_elf32_vxworks_vec
#undef TARGET_LITTLE_NAME
#define TARGET_LITTLE_NAME "elf32-i386-vxworks"
#undef ELF_OSABI
projects / thirdparty / binutils-gdb.git / blobdiff