/* X86-64 specific support for ELF
- Copyright (C) 2000-2014 Free Software Foundation, Inc.
+ Copyright (C) 2000-2016 Free Software Foundation, Inc.
Contributed by Jan Hubicka <jh@suse.cz>.
This file is part of BFD, the Binary File Descriptor library.
#include "dwarf2.h"
#include "libiberty.h"
+#include "opcode/i386.h"
#include "elf/x86-64.h"
#ifdef CORE_HEADER
special_function, name, partial_inplace, src_mask, dst_mask, pcrel_offset. */
static reloc_howto_type x86_64_elf_howto_table[] =
{
- HOWTO(R_X86_64_NONE, 0, 0, 0, FALSE, 0, complain_overflow_dont,
+ HOWTO(R_X86_64_NONE, 0, 3, 0, FALSE, 0, complain_overflow_dont,
bfd_elf_generic_reloc, "R_X86_64_NONE", FALSE, 0x00000000, 0x00000000,
FALSE),
HOWTO(R_X86_64_64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
HOWTO(R_X86_64_PLT32_BND, 0, 2, 32, TRUE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_PLT32_BND", FALSE, 0xffffffff, 0xffffffff,
TRUE),
+ HOWTO(R_X86_64_GOTPCRELX, 0, 2, 32, TRUE, 0, complain_overflow_signed,
+ bfd_elf_generic_reloc, "R_X86_64_GOTPCRELX", FALSE, 0xffffffff,
+ 0xffffffff, TRUE),
+ HOWTO(R_X86_64_REX_GOTPCRELX, 0, 2, 32, TRUE, 0, complain_overflow_signed,
+ bfd_elf_generic_reloc, "R_X86_64_REX_GOTPCRELX", FALSE, 0xffffffff,
+ 0xffffffff, TRUE),
/* We have a gap in the reloc numbers here.
R_X86_64_standard counts the number up to this point, and
R_X86_64_vt_offset is the value to subtract from a reloc type of
R_X86_64_GNU_VT* to form an index into this table. */
-#define R_X86_64_standard (R_X86_64_PLT32_BND + 1)
+#define R_X86_64_standard (R_X86_64_REX_GOTPCRELX + 1)
#define R_X86_64_vt_offset (R_X86_64_GNU_VTINHERIT - R_X86_64_standard)
/* GNU extension to record C++ vtable hierarchy. */
{ BFD_RELOC_X86_64_TLSDESC_CALL, R_X86_64_TLSDESC_CALL, },
{ BFD_RELOC_X86_64_TLSDESC, R_X86_64_TLSDESC, },
{ BFD_RELOC_X86_64_IRELATIVE, R_X86_64_IRELATIVE, },
- { BFD_RELOC_X86_64_PC32_BND, R_X86_64_PC32_BND,},
- { BFD_RELOC_X86_64_PLT32_BND, R_X86_64_PLT32_BND,},
+ { BFD_RELOC_X86_64_PC32_BND, R_X86_64_PC32_BND, },
+ { BFD_RELOC_X86_64_PLT32_BND, R_X86_64_PLT32_BND, },
+ { BFD_RELOC_X86_64_GOTPCRELX, R_X86_64_GOTPCRELX, },
+ { BFD_RELOC_X86_64_REX_GOTPCRELX, R_X86_64_REX_GOTPCRELX, },
{ BFD_RELOC_VTABLE_INHERIT, R_X86_64_GNU_VTINHERIT, },
{ BFD_RELOC_VTABLE_ENTRY, R_X86_64_GNU_VTENTRY, },
};
return elf_x86_64_rtype_to_howto (abfd,
x86_64_reloc_map[i].elf_reloc_val);
}
- return 0;
+ return NULL;
}
static reloc_howto_type *
#define elf_backend_arch_data &elf_x86_64_arch_bed
+/* Is a undefined weak symbol which is resolved to 0. Reference to an
+ undefined weak symbol is resolved to 0 when building executable if
+ it isn't dynamic and
+ 1. Has non-GOT/non-PLT relocations in text section. Or
+ 2. Has no GOT/PLT relocation.
+ */
+#define UNDEFINED_WEAK_RESOLVED_TO_ZERO(INFO, EH) \
+ ((EH)->elf.root.type == bfd_link_hash_undefweak \
+ && bfd_link_executable (INFO) \
+ && (elf_x86_64_hash_table (INFO)->interp == NULL \
+ || !(EH)->has_got_reloc \
+ || (EH)->has_non_got_reloc \
+ || !(INFO)->dynamic_undefined_weak))
+
/* x86-64 ELF linker hash entry. */
struct elf_x86_64_link_hash_entry
(GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type))
unsigned char tls_type;
+ /* TRUE if a weak symbol with a real definition needs a copy reloc.
+ When there is a weak symbol with a real definition, the processor
+ independent code will have arranged for us to see the real
+ definition first. We need to copy the needs_copy bit from the
+ real definition and check it when allowing copy reloc in PIE. */
+ unsigned int needs_copy : 1;
+
/* TRUE if symbol has at least one BND relocation. */
- bfd_boolean has_bnd_reloc;
+ unsigned int has_bnd_reloc : 1;
+
+ /* TRUE if symbol has GOT or PLT relocations. */
+ unsigned int has_got_reloc : 1;
+
+ /* TRUE if symbol has non-GOT/non-PLT relocations in text sections. */
+ unsigned int has_non_got_reloc : 1;
+
+ /* Reference count of C/C++ function pointer relocations in read-write
+ section which can be resolved at run-time. */
+ bfd_signed_vma func_pointer_refcount;
/* Information about the GOT PLT entry. Filled when there are both
GOT and PLT relocations against the same function. */
struct elf_link_hash_table elf;
/* Short-cuts to get to dynamic linker sections. */
+ asection *interp;
asection *sdynbss;
asection *srelbss;
asection *plt_eh_frame;
eh = (struct elf_x86_64_link_hash_entry *) entry;
eh->dyn_relocs = NULL;
eh->tls_type = GOT_UNKNOWN;
- eh->has_bnd_reloc = FALSE;
+ eh->needs_copy = 0;
+ eh->has_bnd_reloc = 0;
+ eh->has_got_reloc = 0;
+ eh->has_non_got_reloc = 0;
+ eh->func_pointer_refcount = 0;
eh->plt_bnd.offset = (bfd_vma) -1;
eh->plt_got.offset = (bfd_vma) -1;
eh->tlsdesc_got = (bfd_vma) -1;
ret->elf.indx = sec->id;
ret->elf.dynstr_index = htab->r_sym (rel->r_info);
ret->elf.dynindx = -1;
+ ret->func_pointer_refcount = 0;
ret->plt_got.offset = (bfd_vma) -1;
*slot = ret;
}
return FALSE;
htab->sdynbss = bfd_get_linker_section (dynobj, ".dynbss");
- if (!info->shared)
- htab->srelbss = bfd_get_linker_section (dynobj, ".rela.bss");
-
- if (!htab->sdynbss
- || (!info->shared && !htab->srelbss))
+ if (!htab->sdynbss)
abort ();
+ if (bfd_link_executable (info))
+ {
+ /* Always allow copy relocs for building executables. */
+ asection *s = bfd_get_linker_section (dynobj, ".rela.bss");
+ if (s == NULL)
+ {
+ const struct elf_backend_data *bed = get_elf_backend_data (dynobj);
+ s = bfd_make_section_anyway_with_flags (dynobj,
+ ".rela.bss",
+ (bed->dynamic_sec_flags
+ | SEC_READONLY));
+ if (s == NULL
+ || ! bfd_set_section_alignment (dynobj, s,
+ bed->s->log_file_align))
+ return FALSE;
+ }
+ htab->srelbss = s;
+ }
+
if (!info->no_ld_generated_unwind_info
&& htab->plt_eh_frame == NULL
&& htab->elf.splt != NULL)
if (!edir->has_bnd_reloc)
edir->has_bnd_reloc = eind->has_bnd_reloc;
+ if (!edir->has_got_reloc)
+ edir->has_got_reloc = eind->has_got_reloc;
+
+ if (!edir->has_non_got_reloc)
+ edir->has_non_got_reloc = eind->has_non_got_reloc;
+
if (eind->dyn_relocs != NULL)
{
if (edir->dyn_relocs != NULL)
dir->pointer_equality_needed |= ind->pointer_equality_needed;
}
else
- _bfd_elf_link_hash_copy_indirect (info, dir, ind);
+ {
+ if (eind->func_pointer_refcount > 0)
+ {
+ edir->func_pointer_refcount += eind->func_pointer_refcount;
+ eind->func_pointer_refcount = 0;
+ }
+
+ _bfd_elf_link_hash_copy_indirect (info, dir, ind);
+ }
}
static bfd_boolean
case R_X86_64_GOTPC32_TLSDESC:
case R_X86_64_TLSDESC_CALL:
case R_X86_64_GOTTPOFF:
- if (info->executable)
+ if (bfd_link_executable (info))
{
if (h == NULL)
to_type = R_X86_64_TPOFF32;
{
unsigned int new_to_type = to_type;
- if (info->executable
+ if (bfd_link_executable (info)
&& h != NULL
&& h->dynindx == -1
&& tls_type == GOT_TLS_IE)
break;
case R_X86_64_TLSLD:
- if (info->executable)
+ if (bfd_link_executable (info))
to_type = R_X86_64_TPOFF32;
break;
return TRUE;
}
+/* Rename some of the generic section flags to better document how they
+ are used here. */
+#define need_convert_load sec_flg0
+
/* Look through the relocs for a section during the first phase, and
calculate needed space in the global offset table, procedure
linkage table, and dynamic reloc sections. */
asection *sreloc;
bfd_boolean use_plt_got;
- if (info->relocatable)
+ if (bfd_link_relocatable (info))
return TRUE;
BFD_ASSERT (is_x86_64_elf (abfd));
unsigned int r_type;
unsigned long r_symndx;
struct elf_link_hash_entry *h;
+ struct elf_x86_64_link_hash_entry *eh;
Elf_Internal_Sym *isym;
const char *name;
bfd_boolean size_reloc;
&& (get_elf_x86_64_backend_data (abfd)
== &elf_x86_64_arch_bed))
{
- elf_x86_64_hash_entry (h)->has_bnd_reloc = TRUE;
+ elf_x86_64_hash_entry (h)->has_bnd_reloc = 1;
/* Create the second PLT for Intel MPX support. */
if (htab->plt_bnd == NULL)
case R_X86_64_32S:
case R_X86_64_PC64:
case R_X86_64_GOTPCREL:
+ case R_X86_64_GOTPCRELX:
+ case R_X86_64_REX_GOTPCRELX:
case R_X86_64_GOTPCREL64:
if (htab->elf.dynobj == NULL)
htab->elf.dynobj = abfd;
/* It is referenced by a non-shared object. */
h->ref_regular = 1;
h->root.non_ir_ref = 1;
+
+ if (h->type == STT_GNU_IFUNC)
+ elf_tdata (info->output_bfd)->has_gnu_symbols
+ |= elf_gnu_symbol_ifunc;
}
if (! elf_x86_64_tls_transition (info, abfd, sec, NULL,
rel, rel_end, h, r_symndx))
return FALSE;
+ eh = (struct elf_x86_64_link_hash_entry *) h;
switch (r_type)
{
case R_X86_64_TLSLD:
goto create_got;
case R_X86_64_TPOFF32:
- if (!info->executable && ABI_64_P (abfd))
+ if (!bfd_link_executable (info) && ABI_64_P (abfd))
{
if (h)
name = h->root.root.string;
bfd_set_error (bfd_error_bad_value);
return FALSE;
}
+ if (eh != NULL)
+ eh->has_got_reloc = 1;
break;
case R_X86_64_GOTTPOFF:
- if (!info->executable)
+ if (!bfd_link_executable (info))
info->flags |= DF_STATIC_TLS;
/* Fall through */
case R_X86_64_GOT32:
case R_X86_64_GOTPCREL:
+ case R_X86_64_GOTPCRELX:
+ case R_X86_64_REX_GOTPCRELX:
case R_X86_64_TLSGD:
case R_X86_64_GOT64:
case R_X86_64_GOTPCREL64:
if (h != NULL)
{
h->got.refcount += 1;
- old_tls_type = elf_x86_64_hash_entry (h)->tls_type;
+ old_tls_type = eh->tls_type;
}
else
{
if (old_tls_type != tls_type)
{
- if (h != NULL)
- elf_x86_64_hash_entry (h)->tls_type = tls_type;
+ if (eh != NULL)
+ eh->tls_type = tls_type;
else
elf_x86_64_local_got_tls_type (abfd) [r_symndx] = tls_type;
}
case R_X86_64_GOTPC32:
case R_X86_64_GOTPC64:
create_got:
+ if (eh != NULL)
+ eh->has_got_reloc = 1;
if (htab->elf.sgot == NULL)
{
if (htab->elf.dynobj == NULL)
if (h == NULL)
continue;
+ eh->has_got_reloc = 1;
h->needs_plt = 1;
h->plt.refcount += 1;
break;
/* Let's help debug shared library creation. These relocs
cannot be used in shared libs. Don't error out for
sections we don't care about, such as debug sections or
- non-constant sections. */
- if (info->shared
+ non-constant sections, or when relocation overflow check
+ is disabled. */
+ if (!info->no_reloc_overflow_check
+ && bfd_link_pic (info)
&& (sec->flags & SEC_ALLOC) != 0
&& (sec->flags & SEC_READONLY) != 0)
{
case R_X86_64_PC64:
case R_X86_64_64:
pointer:
- if (h != NULL && info->executable)
+ if (eh != NULL && (sec->flags & SEC_CODE) != 0)
+ eh->has_non_got_reloc = 1;
+ /* STT_GNU_IFUNC symbol must go through PLT even if it is
+ locally defined and undefined symbol may turn out to be
+ a STT_GNU_IFUNC symbol later. */
+ if (h != NULL
+ && (bfd_link_executable (info)
+ || ((h->type == STT_GNU_IFUNC
+ || h->root.type == bfd_link_hash_undefweak
+ || h->root.type == bfd_link_hash_undefined)
+ && SYMBOLIC_BIND (info, h))))
{
/* If this reloc is in a read-only section, we might
need a copy reloc. We can't check reliably at this
/* We may need a .plt entry if the function this reloc
refers to is in a shared lib. */
h->plt.refcount += 1;
- if (r_type != R_X86_64_PC32
- && r_type != R_X86_64_PC32_BND
- && r_type != R_X86_64_PC64)
- h->pointer_equality_needed = 1;
+ if (r_type == R_X86_64_PC32)
+ {
+ /* Since something like ".long foo - ." may be used
+ as pointer, make sure that PLT is used if foo is
+ a function defined in a shared library. */
+ if ((sec->flags & SEC_CODE) == 0)
+ h->pointer_equality_needed = 1;
+ }
+ else if (r_type != R_X86_64_PC32_BND
+ && r_type != R_X86_64_PC64)
+ {
+ h->pointer_equality_needed = 1;
+ /* At run-time, R_X86_64_64 can be resolved for both
+ x86-64 and x32. But R_X86_64_32 and R_X86_64_32S
+ can only be resolved for x32. */
+ if ((sec->flags & SEC_READONLY) == 0
+ && (r_type == R_X86_64_64
+ || (!ABI_64_P (abfd)
+ && (r_type == R_X86_64_32
+ || r_type == R_X86_64_32S))))
+ eh->func_pointer_refcount += 1;
+ }
}
size_reloc = FALSE;
may need to keep relocations for symbols satisfied by a
dynamic library if we manage to avoid copy relocs for the
symbol. */
- if ((info->shared
+ if ((bfd_link_pic (info)
&& (sec->flags & SEC_ALLOC) != 0
&& (! IS_X86_64_PCREL_TYPE (r_type)
|| (h != NULL
- && (! SYMBOLIC_BIND (info, h)
+ && (! (bfd_link_pie (info)
+ || SYMBOLIC_BIND (info, h))
|| h->root.type == bfd_link_hash_defweak
|| !h->def_regular))))
|| (ELIMINATE_COPY_RELOCS
- && !info->shared
+ && !bfd_link_pic (info)
&& (sec->flags & SEC_ALLOC) != 0
&& h != NULL
&& (h->root.type == bfd_link_hash_defweak
/* If this is a global symbol, we count the number of
relocations we need for this symbol. */
if (h != NULL)
- {
- head = &((struct elf_x86_64_link_hash_entry *) h)->dyn_relocs;
- }
+ head = &eh->dyn_relocs;
else
{
/* Track dynamic relocs needed for local syms too.
if (use_plt_got
&& h != NULL
&& h->plt.refcount > 0
- && h->got.refcount > 0
+ && (((info->flags & DF_BIND_NOW) && !h->pointer_equality_needed)
+ || h->got.refcount > 0)
&& htab->plt_got == NULL)
{
/* Create the GOT procedure linkage table. */
plt_got_align))
return FALSE;
}
+
+ if ((r_type == R_X86_64_GOTPCREL
+ || r_type == R_X86_64_GOTPCRELX
+ || r_type == R_X86_64_REX_GOTPCRELX)
+ && (h == NULL || h->type != STT_GNU_IFUNC))
+ sec->need_convert_load = 1;
}
return TRUE;
bfd_signed_vma *local_got_refcounts;
const Elf_Internal_Rela *rel, *relend;
- if (info->relocatable)
+ if (bfd_link_relocatable (info))
return TRUE;
htab = elf_x86_64_hash_table (info);
unsigned long r_symndx;
unsigned int r_type;
struct elf_link_hash_entry *h = NULL;
+ bfd_boolean pointer_reloc;
r_symndx = htab->r_sym (rel->r_info);
if (r_symndx >= symtab_hdr->sh_info)
rel, relend, h, r_symndx))
return FALSE;
+ pointer_reloc = FALSE;
switch (r_type)
{
case R_X86_64_TLSLD:
case R_X86_64_GOTTPOFF:
case R_X86_64_GOT32:
case R_X86_64_GOTPCREL:
+ case R_X86_64_GOTPCRELX:
+ case R_X86_64_REX_GOTPCRELX:
case R_X86_64_GOT64:
case R_X86_64_GOTPCREL64:
case R_X86_64_GOTPLT64:
}
break;
- case R_X86_64_8:
- case R_X86_64_16:
case R_X86_64_32:
- case R_X86_64_64:
case R_X86_64_32S:
+ pointer_reloc = !ABI_64_P (abfd);
+ goto pointer;
+
+ case R_X86_64_64:
+ pointer_reloc = TRUE;
+ case R_X86_64_8:
+ case R_X86_64_16:
case R_X86_64_PC8:
case R_X86_64_PC16:
case R_X86_64_PC32:
case R_X86_64_PC64:
case R_X86_64_SIZE32:
case R_X86_64_SIZE64:
- if (info->shared
+pointer:
+ if (bfd_link_pic (info)
&& (h == NULL || h->type != STT_GNU_IFUNC))
break;
/* Fall thru */
{
if (h->plt.refcount > 0)
h->plt.refcount -= 1;
+ if (pointer_reloc && (sec->flags & SEC_READONLY) == 0)
+ {
+ struct elf_x86_64_link_hash_entry *eh
+ = (struct elf_x86_64_link_hash_entry *) h;
+ if (eh->func_pointer_refcount > 0)
+ eh->func_pointer_refcount -= 1;
+ }
}
break;
return TRUE;
}
+/* Remove undefined weak symbol from the dynamic symbol table if it
+ is resolved to 0. */
+
+static bfd_boolean
+elf_x86_64_fixup_symbol (struct bfd_link_info *info,
+ struct elf_link_hash_entry *h)
+{
+ if (h->dynindx != -1
+ && UNDEFINED_WEAK_RESOLVED_TO_ZERO (info,
+ elf_x86_64_hash_entry (h)))
+ {
+ h->dynindx = -1;
+ _bfd_elf_strtab_delref (elf_hash_table (info)->dynstr,
+ h->dynstr_index);
+ }
+ return TRUE;
+}
+
/* Adjust a symbol defined by a dynamic object and referenced by a
regular object. The current definition is in some section of the
dynamic object, but we're not including those sections. We have to
h->root.u.def.section = h->u.weakdef->root.u.def.section;
h->root.u.def.value = h->u.weakdef->root.u.def.value;
if (ELIMINATE_COPY_RELOCS || info->nocopyreloc)
- h->non_got_ref = h->u.weakdef->non_got_ref;
+ {
+ eh = (struct elf_x86_64_link_hash_entry *) h;
+ h->non_got_ref = h->u.weakdef->non_got_ref;
+ eh->needs_copy = h->u.weakdef->needs_copy;
+ }
return TRUE;
}
only references to the symbol are via the global offset table.
For such cases we need not do anything here; the relocations will
be handled correctly by relocate_section. */
- if (info->shared)
+ if (!bfd_link_executable (info))
return TRUE;
/* If there are no references to this symbol that do not use the
s = htab->sdynbss;
- return _bfd_elf_adjust_dynamic_copy (h, s);
+ return _bfd_elf_adjust_dynamic_copy (info, h, s);
}
/* Allocate space in .plt, .got and associated reloc sections for
struct elf_dyn_relocs *p;
const struct elf_backend_data *bed;
unsigned int plt_entry_size;
+ bfd_boolean resolved_to_zero;
if (h->root.type == bfd_link_hash_indirect)
return TRUE;
bed = get_elf_backend_data (info->output_bfd);
plt_entry_size = GET_PLT_ENTRY_SIZE (info->output_bfd);
+ resolved_to_zero = UNDEFINED_WEAK_RESOLVED_TO_ZERO (info, eh);
+
/* 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
eh->plt_got.refcount = 1;
}
+ /* 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;
+
/* 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
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 > 0 || eh->plt_got.refcount > 0))
+ && (h->plt.refcount > eh->func_pointer_refcount
+ || eh->plt_got.refcount > 0))
{
- bfd_boolean use_plt_got = eh->plt_got.refcount > 0;
+ bfd_boolean use_plt_got;
+
+ /* Clear the reference count of function pointer relocations
+ if PLT is used. */
+ eh->func_pointer_refcount = 0;
+
+ if ((info->flags & DF_BIND_NOW) && !h->pointer_equality_needed)
+ {
+ /* Don't use the regular PLT for DF_BIND_NOW. */
+ h->plt.offset = (bfd_vma) -1;
+
+ /* Use the GOT PLT. */
+ h->got.refcount = 1;
+ eh->plt_got.refcount = 1;
+ }
+
+ 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
- && !h->forced_local)
+ && !h->forced_local
+ && !resolved_to_zero)
{
if (! bfd_elf_link_record_dynamic_symbol (info, h))
return FALSE;
}
- if (info->shared
+ if (bfd_link_pic (info)
|| 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. */
+ first entry. The .plt section is used by prelink to undo
+ prelinking for dynamic relocations. */
if (s->size == 0)
s->size = plt_entry_size;
location in the .plt. This is required to make function
pointers compare as equal between the normal executable and
the shared library. */
- if (! info->shared
+ if (! bfd_link_pic (info)
&& !h->def_regular)
{
if (use_plt_got)
script. */
htab->elf.sgotplt->size += GOT_ENTRY_SIZE;
- /* We also need to make an entry in the .rela.plt
- section. */
- htab->elf.srelplt->size += bed->s->sizeof_rela;
- htab->elf.srelplt->reloc_count++;
+ /* 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 .rela.plt
+ section. */
+ htab->elf.srelplt->size += bed->s->sizeof_rela;
+ htab->elf.srelplt->reloc_count++;
+ }
}
}
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;
}
/* If R_X86_64_GOTTPOFF symbol is now local to the binary,
make it a R_X86_64_TPOFF32 requiring no GOT entry. */
if (h->got.refcount > 0
- && info->executable
+ && bfd_link_executable (info)
&& h->dynindx == -1
&& elf_x86_64_hash_entry (h)->tls_type == GOT_TLS_IE)
{
/* 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)
+ && !h->forced_local
+ && !resolved_to_zero)
{
if (! bfd_elf_link_record_dynamic_symbol (info, h))
return FALSE;
}
dyn = htab->elf.dynamic_sections_created;
/* R_X86_64_TLSGD needs one dynamic relocation if local symbol
- and two if global.
- R_X86_64_GOTTPOFF needs one dynamic relocation. */
+ and two if global. R_X86_64_GOTTPOFF needs one dynamic
+ relocation. No dynamic relocation against resolved undefined
+ weak symbol in executable. */
if ((GOT_TLS_GD_P (tls_type) && h->dynindx == -1)
|| tls_type == GOT_TLS_IE)
htab->elf.srelgot->size += bed->s->sizeof_rela;
else if (GOT_TLS_GD_P (tls_type))
htab->elf.srelgot->size += 2 * bed->s->sizeof_rela;
else if (! GOT_TLS_GDESC_P (tls_type)
- && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
+ && ((ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
+ && !resolved_to_zero)
|| h->root.type != bfd_link_hash_undefweak)
- && (info->shared
+ && (bfd_link_pic (info)
|| WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h)))
htab->elf.srelgot->size += bed->s->sizeof_rela;
if (GOT_TLS_GDESC_P (tls_type))
space for pc-relative relocs that have become local due to symbol
visibility changes. */
- if (info->shared)
+ if (bfd_link_pic (info))
{
/* Relocs that use pc_count are those that appear on a call
insn, or certain REL relocs that can generated via assembly.
}
/* Also discard relocs on undefined weak syms with non-default
- visibility. */
- if (eh->dyn_relocs != NULL
- && h->root.type == bfd_link_hash_undefweak)
+ visibility or in PIE. */
+ if (eh->dyn_relocs != NULL)
{
- if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
- eh->dyn_relocs = NULL;
-
- /* Make sure undefined weak symbols are output as a dynamic
- symbol in PIEs. */
- else if (h->dynindx == -1
- && ! h->forced_local
- && ! bfd_elf_link_record_dynamic_symbol (info, h))
- return FALSE;
- }
+ if (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)
+ eh->dyn_relocs = NULL;
+ else if (h->dynindx == -1
+ && ! h->forced_local
+ && ! bfd_elf_link_record_dynamic_symbol (info, h))
+ return FALSE;
+ }
+ /* For PIE, discard space for pc-relative relocs against
+ symbols which turn out to need copy relocs. */
+ else if (bfd_link_executable (info)
+ && (h->needs_copy || eh->needs_copy)
+ && h->def_dynamic
+ && !h->def_regular)
+ {
+ struct elf_dyn_relocs **pp;
+ for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
+ {
+ if (p->pc_count != 0)
+ *pp = p->next;
+ else
+ pp = &p->next;
+ }
+ }
+ }
}
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. */
+ dynamic. Keep dynamic relocations for run-time function
+ pointer initialization. */
- if (!h->non_got_ref
+ 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
Undefined weak syms won't yet be marked as dynamic. */
if (h->dynindx == -1
&& ! h->forced_local
+ && ! resolved_to_zero
&& ! bfd_elf_link_record_dynamic_symbol (info, h))
return FALSE;
}
eh->dyn_relocs = NULL;
+ eh->func_pointer_refcount = 0;
keep: ;
}
info->flags |= DF_TEXTREL;
- if (info->warn_shared_textrel && info->shared)
- info->callbacks->einfo (_("%P: %B: warning: relocation against `%s' in readonly section `%A'.\n"),
+ if ((info->warn_shared_textrel && bfd_link_pic (info))
+ || info->error_textrel)
+ info->callbacks->einfo (_("%P: %B: warning: relocation against `%s' in readonly section `%A'\n"),
p->sec->owner, h->root.root.string,
p->sec);
return TRUE;
}
-/* Convert
+/* With the local symbol, foo, we convert
mov foo@GOTPCREL(%rip), %reg
to
lea foo(%rip), %reg
- with the local symbol, foo. */
+ and convert
+ call/jmp *foo@GOTPCREL(%rip)
+ to
+ nop call foo/jmp foo nop
+ When PIC is false, convert
+ test %reg, foo@GOTPCREL(%rip)
+ to
+ test $foo, %reg
+ and convert
+ binop foo@GOTPCREL(%rip), %reg
+ to
+ binop $foo, %reg
+ where binop is one of adc, add, and, cmp, or, sbb, sub, xor
+ instructions. */
static bfd_boolean
-elf_x86_64_convert_mov_to_lea (bfd *abfd, asection *sec,
- struct bfd_link_info *link_info)
+elf_x86_64_convert_load (bfd *abfd, asection *sec,
+ struct bfd_link_info *link_info)
{
Elf_Internal_Shdr *symtab_hdr;
Elf_Internal_Rela *internal_relocs;
bfd_boolean changed_contents;
bfd_boolean changed_relocs;
bfd_signed_vma *local_got_refcounts;
+ bfd_vma maxpagesize;
+ bfd_boolean is_pic;
+ bfd_boolean require_reloc_pc32;
/* Don't even try to convert non-ELF outputs. */
if (!is_elf_hash_table (link_info->hash))
return FALSE;
- /* Nothing to do if there are no codes, no relocations or no output. */
+ /* Nothing to do if there is no need or no output. */
if ((sec->flags & (SEC_CODE | SEC_RELOC)) != (SEC_CODE | SEC_RELOC)
- || sec->reloc_count == 0
+ || sec->need_convert_load == 0
|| bfd_is_abs_section (sec->output_section))
return TRUE;
changed_contents = FALSE;
changed_relocs = FALSE;
local_got_refcounts = elf_local_got_refcounts (abfd);
+ maxpagesize = get_elf_backend_data (abfd)->maxpagesize;
/* Get the section contents. */
if (elf_section_data (sec)->this_hdr.contents != NULL)
goto error_return;
}
+ is_pic = bfd_link_pic (link_info);
+
+ /* TRUE if we can convert only to R_X86_64_PC32. Enable it for
+ --no-relax. */
+ require_reloc_pc32
+ = link_info->disable_target_specific_optimizations > 1;
+
irelend = internal_relocs + sec->reloc_count;
for (irel = internal_relocs; irel < irelend; irel++)
{
unsigned int r_symndx = htab->r_sym (irel->r_info);
unsigned int indx;
struct elf_link_hash_entry *h;
+ asection *tsec;
+ char symtype;
+ bfd_vma toff, roff;
+ bfd_signed_vma raddend;
+ unsigned int opcode;
+ unsigned int modrm;
+ bfd_boolean relocx;
+ bfd_boolean to_reloc_pc32;
+
+ relocx = (r_type == R_X86_64_GOTPCRELX
+ || r_type == R_X86_64_REX_GOTPCRELX);
+ if (!relocx && r_type != R_X86_64_GOTPCREL)
+ continue;
+
+ roff = irel->r_offset;
+ if (roff < (r_type == R_X86_64_REX_GOTPCRELX ? 3 : 2))
+ continue;
- if (r_type != R_X86_64_GOTPCREL)
+ raddend = irel->r_addend;
+ /* Addend for 32-bit PC-relative relocation must be -4. */
+ if (raddend != -4)
continue;
+ opcode = bfd_get_8 (abfd, contents + roff - 2);
+
+ /* Convert mov to lea since it has been done for a while. */
+ if (opcode != 0x8b)
+ {
+ /* Only convert R_X86_64_GOTPCRELX and R_X86_64_REX_GOTPCRELX
+ for call, jmp or one of adc, add, and, cmp, or, sbb, sub,
+ test, xor instructions. */
+ if (!relocx)
+ continue;
+ }
+
+ /* We convert only to R_X86_64_PC32:
+ 1. Branch.
+ 2. R_X86_64_GOTPCREL since we can't modify REX byte.
+ 3. require_reloc_pc32 is true.
+ 4. PIC.
+ */
+ to_reloc_pc32 = (opcode == 0xff
+ || !relocx
+ || require_reloc_pc32
+ || is_pic);
+
/* Get the symbol referred to by the reloc. */
if (r_symndx < symtab_hdr->sh_info)
{
isym = bfd_sym_from_r_symndx (&htab->sym_cache,
abfd, r_symndx);
- /* STT_GNU_IFUNC must keep R_X86_64_GOTPCREL 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)
+ symtype = ELF_ST_TYPE (isym->st_info);
+
+ /* STT_GNU_IFUNC must keep GOTPCREL relocations and skip
+ relocation against undefined symbols. */
+ if (symtype == STT_GNU_IFUNC || isym->st_shndx == SHN_UNDEF)
+ continue;
+
+ if (isym->st_shndx == SHN_ABS)
+ tsec = bfd_abs_section_ptr;
+ else if (isym->st_shndx == SHN_COMMON)
+ tsec = bfd_com_section_ptr;
+ else if (isym->st_shndx == SHN_X86_64_LCOMMON)
+ tsec = &_bfd_elf_large_com_section;
+ else
+ tsec = bfd_section_from_elf_index (abfd, isym->st_shndx);
+
+ h = NULL;
+ toff = isym->st_value;
+ }
+ else
+ {
+ indx = r_symndx - symtab_hdr->sh_info;
+ h = elf_sym_hashes (abfd)[indx];
+ BFD_ASSERT (h != NULL);
+
+ while (h->root.type == bfd_link_hash_indirect
+ || h->root.type == bfd_link_hash_warning)
+ h = (struct elf_link_hash_entry *) h->root.u.i.link;
+
+ /* STT_GNU_IFUNC must keep GOTPCREL relocations. We also
+ avoid optimizing GOTPCREL relocations againt _DYNAMIC
+ since ld.so may use its link-time address. */
+ if (h->type == STT_GNU_IFUNC)
+ continue;
+
+ /* Undefined weak symbol is only bound locally in executable
+ and its reference is resolved as 0 without relocation
+ overflow. We can only perform this optimization for
+ GOTPCRELX relocations since we need to modify REX byte.
+ It is OK convert mov with R_X86_64_GOTPCREL to
+ R_X86_64_PC32. */
+ if ((relocx || opcode == 0x8b)
+ && UNDEFINED_WEAK_RESOLVED_TO_ZERO (link_info,
+ elf_x86_64_hash_entry (h)))
{
- bfd_put_8 (output_bfd, 0x8d,
- contents + irel->r_offset - 2);
- irel->r_info = htab->r_info (r_symndx, R_X86_64_PC32);
- if (local_got_refcounts != NULL
- && local_got_refcounts[r_symndx] > 0)
- local_got_refcounts[r_symndx] -= 1;
- changed_contents = TRUE;
- changed_relocs = TRUE;
+ if (opcode == 0xff)
+ {
+ /* Skip for branch instructions since R_X86_64_PC32
+ may overflow. */
+ if (require_reloc_pc32)
+ continue;
+ }
+ else if (relocx)
+ {
+ /* For non-branch instructions, we can convert to
+ R_X86_64_32/R_X86_64_32S since we know if there
+ is a REX byte. */
+ to_reloc_pc32 = FALSE;
+ }
+
+ /* Since we don't know the current PC when PIC is true,
+ we can't convert to R_X86_64_PC32. */
+ if (to_reloc_pc32 && is_pic)
+ continue;
+
+ goto convert;
}
- continue;
+ else if ((h->def_regular
+ || h->root.type == bfd_link_hash_defined
+ || h->root.type == bfd_link_hash_defweak)
+ && h != htab->elf.hdynamic
+ && SYMBOL_REFERENCES_LOCAL (link_info, h))
+ {
+ /* bfd_link_hash_new or bfd_link_hash_undefined is
+ set by an assignment in a linker script in
+ bfd_elf_record_link_assignment. */
+ if (h->def_regular
+ && (h->root.type == bfd_link_hash_new
+ || h->root.type == bfd_link_hash_undefined))
+ {
+ /* Skip since R_X86_64_32/R_X86_64_32S may overflow. */
+ if (require_reloc_pc32)
+ continue;
+ goto convert;
+ }
+ tsec = h->root.u.def.section;
+ toff = h->root.u.def.value;
+ symtype = h->type;
+ }
+ else
+ continue;
}
- indx = r_symndx - symtab_hdr->sh_info;
- h = elf_sym_hashes (abfd)[indx];
- BFD_ASSERT (h != NULL);
+ /* We can only estimate relocation overflow for R_X86_64_PC32. */
+ if (!to_reloc_pc32)
+ goto convert;
- while (h->root.type == bfd_link_hash_indirect
- || h->root.type == bfd_link_hash_warning)
- h = (struct elf_link_hash_entry *) h->root.u.i.link;
+ if (tsec->sec_info_type == SEC_INFO_TYPE_MERGE)
+ {
+ /* At this stage in linking, no SEC_MERGE symbol has been
+ adjusted, so all references to such symbols need to be
+ passed through _bfd_merged_section_offset. (Later, in
+ relocate_section, all SEC_MERGE symbols *except* for
+ section symbols have been adjusted.)
+
+ gas may reduce relocations against symbols in SEC_MERGE
+ sections to a relocation against the section symbol when
+ the original addend was zero. When the reloc is against
+ a section symbol we should include the addend in the
+ offset passed to _bfd_merged_section_offset, since the
+ location of interest is the original symbol. On the
+ other hand, an access to "sym+addend" where "sym" is not
+ a section symbol should not include the addend; Such an
+ access is presumed to be an offset from "sym"; The
+ location of interest is just "sym". */
+ if (symtype == STT_SECTION)
+ toff += raddend;
+
+ toff = _bfd_merged_section_offset (abfd, &tsec,
+ elf_section_data (tsec)->sec_info,
+ toff);
+
+ if (symtype != STT_SECTION)
+ toff += raddend;
+ }
+ else
+ toff += raddend;
- /* STT_GNU_IFUNC must keep R_X86_64_GOTPCREL relocation. We also
- avoid optimizing _DYNAMIC since ld.so may use its link-time
- address. */
- if (h->def_regular
- && 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)
+ /* Don't convert if R_X86_64_PC32 relocation overflows. */
+ if (tsec->output_section == sec->output_section)
+ {
+ if ((toff - roff + 0x80000000) > 0xffffffff)
+ continue;
+ }
+ else
+ {
+ bfd_signed_vma distance;
+
+ /* At this point, we don't know the load addresses of TSEC
+ section nor SEC section. We estimate the distrance between
+ SEC and TSEC. We store the estimated distances in the
+ compressed_size field of the output section, which is only
+ used to decompress the compressed input section. */
+ if (sec->output_section->compressed_size == 0)
+ {
+ asection *asect;
+ bfd_size_type size = 0;
+ for (asect = link_info->output_bfd->sections;
+ asect != NULL;
+ asect = asect->next)
+ {
+ asection *i;
+ for (i = asect->map_head.s;
+ i != NULL;
+ i = i->map_head.s)
+ {
+ size = align_power (size, i->alignment_power);
+ size += i->size;
+ }
+ asect->compressed_size = size;
+ }
+ }
+
+ /* Don't convert GOTPCREL relocations if TSEC isn't placed
+ after SEC. */
+ distance = (tsec->output_section->compressed_size
+ - sec->output_section->compressed_size);
+ if (distance < 0)
+ continue;
+
+ /* Take PT_GNU_RELRO segment into account by adding
+ maxpagesize. */
+ if ((toff + distance + maxpagesize - roff + 0x80000000)
+ > 0xffffffff)
+ continue;
+ }
+
+convert:
+ if (opcode == 0xff)
+ {
+ /* We have "call/jmp *foo@GOTPCREL(%rip)". */
+ unsigned int nop;
+ unsigned int disp;
+ bfd_vma nop_offset;
+
+ /* Convert R_X86_64_GOTPCRELX and R_X86_64_REX_GOTPCRELX to
+ R_X86_64_PC32. */
+ modrm = bfd_get_8 (abfd, contents + roff - 1);
+ if (modrm == 0x25)
+ {
+ /* Convert to "jmp foo nop". */
+ modrm = 0xe9;
+ nop = NOP_OPCODE;
+ nop_offset = irel->r_offset + 3;
+ disp = bfd_get_32 (abfd, contents + irel->r_offset);
+ irel->r_offset -= 1;
+ bfd_put_32 (abfd, disp, contents + irel->r_offset);
+ }
+ else
+ {
+ /* Convert to "nop call foo". ADDR_PREFIX_OPCODE
+ is a nop prefix. */
+ modrm = 0xe8;
+ nop = link_info->call_nop_byte;
+ if (link_info->call_nop_as_suffix)
+ {
+ nop_offset = irel->r_offset + 3;
+ disp = bfd_get_32 (abfd, contents + irel->r_offset);
+ irel->r_offset -= 1;
+ bfd_put_32 (abfd, disp, contents + irel->r_offset);
+ }
+ else
+ nop_offset = irel->r_offset - 2;
+ }
+ bfd_put_8 (abfd, nop, contents + nop_offset);
+ bfd_put_8 (abfd, modrm, contents + irel->r_offset - 1);
+ r_type = R_X86_64_PC32;
+ }
+ else
+ {
+ unsigned int rex;
+ unsigned int rex_mask = REX_R;
+
+ if (r_type == R_X86_64_REX_GOTPCRELX)
+ rex = bfd_get_8 (abfd, contents + roff - 3);
+ else
+ rex = 0;
+
+ if (opcode == 0x8b)
+ {
+ if (to_reloc_pc32)
+ {
+ /* Convert "mov foo@GOTPCREL(%rip), %reg" to
+ "lea foo(%rip), %reg". */
+ opcode = 0x8d;
+ r_type = R_X86_64_PC32;
+ }
+ else
+ {
+ /* Convert "mov foo@GOTPCREL(%rip), %reg" to
+ "mov $foo, %reg". */
+ opcode = 0xc7;
+ modrm = bfd_get_8 (abfd, contents + roff - 1);
+ modrm = 0xc0 | (modrm & 0x38) >> 3;
+ if ((rex & REX_W) != 0
+ && ABI_64_P (link_info->output_bfd))
+ {
+ /* Keep the REX_W bit in REX byte for LP64. */
+ r_type = R_X86_64_32S;
+ goto rewrite_modrm_rex;
+ }
+ else
+ {
+ /* If the REX_W bit in REX byte isn't needed,
+ use R_X86_64_32 and clear the W bit to avoid
+ sign-extend imm32 to imm64. */
+ r_type = R_X86_64_32;
+ /* Clear the W bit in REX byte. */
+ rex_mask |= REX_W;
+ goto rewrite_modrm_rex;
+ }
+ }
+ }
+ else
+ {
+ /* R_X86_64_PC32 isn't supported. */
+ if (to_reloc_pc32)
+ continue;
+
+ modrm = bfd_get_8 (abfd, contents + roff - 1);
+ if (opcode == 0x85)
+ {
+ /* Convert "test %reg, foo@GOTPCREL(%rip)" to
+ "test $foo, %reg". */
+ modrm = 0xc0 | (modrm & 0x38) >> 3;
+ opcode = 0xf7;
+ }
+ else
+ {
+ /* Convert "binop foo@GOTPCREL(%rip), %reg" to
+ "binop $foo, %reg". */
+ modrm = 0xc0 | (modrm & 0x38) >> 3 | (opcode & 0x3c);
+ opcode = 0x81;
+ }
+
+ /* Use R_X86_64_32 with 32-bit operand to avoid relocation
+ overflow when sign-extending imm32 to imm64. */
+ r_type = (rex & REX_W) != 0 ? R_X86_64_32S : R_X86_64_32;
+
+rewrite_modrm_rex:
+ bfd_put_8 (abfd, modrm, contents + roff - 1);
+
+ if (rex)
+ {
+ /* Move the R bit to the B bit in REX byte. */
+ rex = (rex & ~rex_mask) | (rex & REX_R) >> 2;
+ bfd_put_8 (abfd, rex, contents + roff - 3);
+ }
+
+ /* No addend for R_X86_64_32/R_X86_64_32S relocations. */
+ irel->r_addend = 0;
+ }
+
+ bfd_put_8 (abfd, opcode, contents + roff - 2);
+ }
+
+ irel->r_info = htab->r_info (r_symndx, r_type);
+ changed_contents = TRUE;
+ changed_relocs = TRUE;
+
+ if (h)
{
- bfd_put_8 (output_bfd, 0x8d,
- contents + irel->r_offset - 2);
- irel->r_info = htab->r_info (r_symndx, R_X86_64_PC32);
if (h->got.refcount > 0)
h->got.refcount -= 1;
- changed_contents = TRUE;
- changed_relocs = TRUE;
+ }
+ else
+ {
+ if (local_got_refcounts != NULL
+ && local_got_refcounts[r_symndx] > 0)
+ local_got_refcounts[r_symndx] -= 1;
}
}
if (htab->elf.dynamic_sections_created)
{
/* Set the contents of the .interp section to the interpreter. */
- if (info->executable)
+ if (bfd_link_executable (info) && !info->nointerp)
{
s = bfd_get_linker_section (dynobj, ".interp");
if (s == NULL)
abort ();
s->size = htab->dynamic_interpreter_size;
s->contents = (unsigned char *) htab->dynamic_interpreter;
+ htab->interp = s;
}
}
{
struct elf_dyn_relocs *p;
- if (!elf_x86_64_convert_mov_to_lea (ibfd, s, info))
+ if (!elf_x86_64_convert_load (ibfd, s, info))
return FALSE;
for (p = (struct elf_dyn_relocs *)
&& (info->flags & DF_TEXTREL) == 0)
{
info->flags |= DF_TEXTREL;
- if (info->warn_shared_textrel && info->shared)
- info->callbacks->einfo (_("%P: %B: warning: relocation in readonly section `%A'.\n"),
+ if ((info->warn_shared_textrel && bfd_link_pic (info))
+ || info->error_textrel)
+ info->callbacks->einfo (_("%P: %B: warning: relocation in readonly section `%A'\n"),
p->sec->owner, p->sec);
}
}
if (GOT_TLS_GD_P (*local_tls_type))
s->size += GOT_ENTRY_SIZE;
}
- if (info->shared
+ if (bfd_link_pic (info)
|| GOT_TLS_GD_ANY_P (*local_tls_type)
|| *local_tls_type == GOT_TLS_IE)
{
#define add_dynamic_entry(TAG, VAL) \
_bfd_elf_add_dynamic_entry (info, TAG, VAL)
- if (info->executable)
+ if (bfd_link_executable (info))
{
if (!add_dynamic_entry (DT_DEBUG, 0))
return FALSE;
if (htab->elf.splt->size != 0)
{
- if (!add_dynamic_entry (DT_PLTGOT, 0)
- || !add_dynamic_entry (DT_PLTRELSZ, 0)
- || !add_dynamic_entry (DT_PLTREL, DT_RELA)
- || !add_dynamic_entry (DT_JMPREL, 0))
+ /* DT_PLTGOT is used by prelink even if there is no PLT
+ relocation. */
+ if (!add_dynamic_entry (DT_PLTGOT, 0))
return FALSE;
+ if (htab->elf.srelplt->size != 0)
+ {
+ if (!add_dynamic_entry (DT_PLTRELSZ, 0)
+ || !add_dynamic_entry (DT_PLTREL, DT_RELA)
+ || !add_dynamic_entry (DT_JMPREL, 0))
+ return FALSE;
+ }
+
if (htab->tlsdesc_plt
&& (!add_dynamic_entry (DT_TLSDESC_PLT, 0)
|| !add_dynamic_entry (DT_TLSDESC_GOT, 0)))
if ((info->flags & DF_TEXTREL) != 0)
{
+ if ((elf_tdata (output_bfd)->has_gnu_symbols
+ & elf_gnu_symbol_ifunc) == elf_gnu_symbol_ifunc)
+ {
+ info->callbacks->einfo
+ (_("%P%X: read-only segment has dynamic IFUNC relocations; recompile with -fPIC\n"));
+ bfd_set_error (bfd_error_bad_value);
+ return FALSE;
+ }
+
if (!add_dynamic_entry (DT_TEXTREL, 0))
return FALSE;
}
tlsbase = (struct elf_link_hash_entry *)bh;
tlsbase->def_regular = 1;
tlsbase->other = STV_HIDDEN;
+ tlsbase->root.linker_def = 1;
(*bed->elf_backend_hide_symbol) (info, tlsbase, TRUE);
}
}
struct elf_x86_64_link_hash_table *htab;
struct bfd_link_hash_entry *base;
- if (!info->executable)
+ if (!bfd_link_executable (info))
return;
htab = elf_x86_64_hash_table (info);
&& (contents [offset - 1] & 0xf0) == 0x80));
}
+static bfd_boolean
+elf_x86_64_need_pic (bfd *input_bfd, struct elf_link_hash_entry *h,
+ reloc_howto_type *howto)
+{
+ const char *fmt;
+ const char *v;
+ const char *pic = "";
+
+ switch (ELF_ST_VISIBILITY (h->other))
+ {
+ case STV_HIDDEN:
+ v = _("hidden symbol");
+ break;
+ case STV_INTERNAL:
+ v = _("internal symbol");
+ break;
+ case STV_PROTECTED:
+ v = _("protected symbol");
+ break;
+ default:
+ v = _("symbol");
+ pic = _("; recompile with -fPIC");
+ break;
+ }
+
+ if (h->def_regular)
+ fmt = _("%B: relocation %s against %s `%s' can not be used when making a shared object%s");
+ else
+ fmt = _("%B: relocation %s against undefined %s `%s' can not be used when making a shared object%s");
+
+ (*_bfd_error_handler) (fmt, input_bfd, howto->name,
+ v, h->root.root.string, pic);
+ bfd_set_error (bfd_error_bad_value);
+ return FALSE;
+}
+
/* Relocate an x86_64 ELF section. */
static bfd_boolean
bfd_vma *local_got_offsets;
bfd_vma *local_tlsdesc_gotents;
Elf_Internal_Rela *rel;
+ Elf_Internal_Rela *wrel;
Elf_Internal_Rela *relend;
const unsigned int plt_entry_size = GET_PLT_ENTRY_SIZE (info->output_bfd);
elf_x86_64_set_tls_module_base (info);
- rel = relocs;
+ rel = wrel = relocs;
relend = relocs + input_section->reloc_count;
- for (; rel < relend; rel++)
+ for (; rel < relend; wrel++, rel++)
{
unsigned int r_type;
reloc_howto_type *howto;
int tls_type;
asection *base_got, *resolved_plt;
bfd_vma st_size;
+ bfd_boolean resolved_to_zero;
r_type = ELF32_R_TYPE (rel->r_info);
if (r_type == (int) R_X86_64_GNU_VTINHERIT
|| r_type == (int) R_X86_64_GNU_VTENTRY)
- continue;
+ {
+ if (wrel != rel)
+ *wrel = *rel;
+ continue;
+ }
if (r_type >= (int) R_X86_64_standard)
{
st_size = sym->st_size;
/* Relocate against local STT_GNU_IFUNC symbol. */
- if (!info->relocatable
+ if (!bfd_link_relocatable (info)
&& ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC)
{
h = elf_x86_64_get_local_sym_hash (htab, input_bfd,
}
if (sec != NULL && discarded_section (sec))
- RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
- rel, 1, relend, howto, 0, contents);
+ {
+ _bfd_clear_contents (howto, input_bfd, input_section,
+ contents + rel->r_offset);
+ wrel->r_offset = rel->r_offset;
+ wrel->r_info = 0;
+ wrel->r_addend = 0;
+
+ /* For ld -r, remove relocations in debug sections against
+ sections defined in discarded sections. Not done for
+ eh_frame editing code expects to be present. */
+ if (bfd_link_relocatable (info)
+ && (input_section->flags & SEC_DEBUGGING))
+ wrel--;
- if (info->relocatable)
- continue;
+ continue;
+ }
+
+ if (bfd_link_relocatable (info))
+ {
+ if (wrel != rel)
+ *wrel = *rel;
+ continue;
+ }
if (rel->r_addend == 0 && !ABI_64_P (output_bfd))
{
bfd_vma plt_index;
const char *name;
- if ((input_section->flags & SEC_ALLOC) == 0
- || h->plt.offset == (bfd_vma) -1)
+ if ((input_section->flags & SEC_ALLOC) == 0)
+ {
+ /* Dynamic relocs are not propagated for SEC_DEBUGGING
+ sections because such sections are not SEC_ALLOC and
+ thus ld.so will not process them. */
+ if ((input_section->flags & SEC_DEBUGGING) != 0)
+ continue;
+ abort ();
+ }
+ else if (h->plt.offset == (bfd_vma) -1)
abort ();
/* STT_GNU_IFUNC symbol must go through PLT. */
(*_bfd_error_handler)
(_("%B: relocation %s against STT_GNU_IFUNC "
"symbol `%s' isn't handled by %s"), input_bfd,
- x86_64_elf_howto_table[r_type].name,
- name, __FUNCTION__);
+ howto->name, name, __FUNCTION__);
bfd_set_error (bfd_error_bad_value);
return FALSE;
case R_X86_64_32S:
- if (info->shared)
+ if (bfd_link_pic (info))
abort ();
goto do_relocation;
(*_bfd_error_handler)
(_("%B: relocation %s against STT_GNU_IFUNC "
"symbol `%s' has non-zero addend: %d"),
- input_bfd, x86_64_elf_howto_table[r_type].name,
- name, rel->r_addend);
+ input_bfd, howto->name, name, rel->r_addend);
bfd_set_error (bfd_error_bad_value);
return FALSE;
}
/* Generate dynamic relcoation only when there is a
non-GOT reference in a shared object. */
- if (info->shared && h->non_got_ref)
+ if (bfd_link_pic (info) && h->non_got_ref)
{
Elf_Internal_Rela outrel;
asection *sreloc;
if (h->dynindx == -1
|| h->forced_local
- || info->executable)
+ || bfd_link_executable (info))
{
/* This symbol is resolved locally. */
outrel.r_info = htab->r_info (0, R_X86_64_IRELATIVE);
goto do_relocation;
case R_X86_64_GOTPCREL:
+ case R_X86_64_GOTPCRELX:
+ case R_X86_64_REX_GOTPCRELX:
case R_X86_64_GOTPCREL64:
base_got = htab->elf.sgot;
off = h->got.offset;
}
}
+ resolved_to_zero = (eh != NULL
+ && UNDEFINED_WEAK_RESOLVED_TO_ZERO (info, eh));
+
/* When generating a shared object, the relocations handled here are
copied into the output file to be resolved at run time. */
switch (r_type)
/* Relocation is to the entry for this symbol in the global
offset table. */
case R_X86_64_GOTPCREL:
+ case R_X86_64_GOTPCRELX:
+ case R_X86_64_REX_GOTPCRELX:
case R_X86_64_GOTPCREL64:
/* Use global offset table entry as symbol value. */
case R_X86_64_GOTPLT64:
dyn = htab->elf.dynamic_sections_created;
- if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info->shared, h)
- || (info->shared
+ if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, bfd_link_pic (info), h)
+ || (bfd_link_pic (info)
&& SYMBOL_REFERENCES_LOCAL (info, h))
|| (ELF_ST_VISIBILITY (h->other)
&& h->root.type == bfd_link_hash_undefweak))
bfd_put_64 (output_bfd, relocation,
base_got->contents + off);
- if (info->shared)
+ if (bfd_link_pic (info))
{
asection *s;
Elf_Internal_Rela outrel;
relocation = base_got->output_section->vma
+ base_got->output_offset + off;
- if (r_type != R_X86_64_GOTPCREL && r_type != R_X86_64_GOTPCREL64)
+ if (r_type != R_X86_64_GOTPCREL
+ && r_type != R_X86_64_GOTPCRELX
+ && r_type != R_X86_64_REX_GOTPCRELX
+ && r_type != R_X86_64_GOTPCREL64)
relocation -= htab->elf.sgotplt->output_section->vma
- htab->elf.sgotplt->output_offset;
/* Relocation is relative to the start of the global offset
table. */
- /* Check to make sure it isn't a protected function symbol
- for shared library since it may not be local when used
- as function address. */
- if (!info->executable
- && h
- && !SYMBOLIC_BIND (info, h)
- && h->def_regular
- && h->type == STT_FUNC
- && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
+ /* Check to make sure it isn't a protected function or data
+ symbol for shared library since it may not be local when
+ used as function address or with copy relocation. We also
+ need to make sure that a symbol is referenced locally. */
+ if (bfd_link_pic (info) && h)
{
- (*_bfd_error_handler)
- (_("%B: relocation R_X86_64_GOTOFF64 against protected function `%s' can not be used when making a shared object"),
- input_bfd, h->root.root.string);
- bfd_set_error (bfd_error_bad_value);
+ if (!h->def_regular)
+ {
+ const char *v;
+
+ switch (ELF_ST_VISIBILITY (h->other))
+ {
+ case STV_HIDDEN:
+ v = _("hidden symbol");
+ break;
+ case STV_INTERNAL:
+ v = _("internal symbol");
+ break;
+ case STV_PROTECTED:
+ v = _("protected symbol");
+ break;
+ default:
+ v = _("symbol");
+ break;
+ }
+
+ (*_bfd_error_handler)
+ (_("%B: relocation R_X86_64_GOTOFF64 against undefined %s `%s' can not be used when making a shared object"),
+ input_bfd, v, h->root.root.string);
+ bfd_set_error (bfd_error_bad_value);
+ return FALSE;
+ }
+ else if (!bfd_link_executable (info)
+ && !SYMBOL_REFERENCES_LOCAL (info, h)
+ && (h->type == STT_FUNC
+ || h->type == STT_OBJECT)
+ && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
+ {
+ (*_bfd_error_handler)
+ (_("%B: relocation R_X86_64_GOTOFF64 against protected %s `%s' can not be used when making a shared object"),
+ input_bfd,
+ h->type == STT_FUNC ? "function" : "data",
+ h->root.root.string);
+ bfd_set_error (bfd_error_bad_value);
return FALSE;
+ }
}
/* Note that sgot is not involved in this
case R_X86_64_PC16:
case R_X86_64_PC32:
case R_X86_64_PC32_BND:
- if (info->shared
- && (input_section->flags & SEC_ALLOC) != 0
+ /* Don't complain about -fPIC if the symbol is undefined when
+ building executable unless it is unresolved weak symbol. */
+ if ((input_section->flags & SEC_ALLOC) != 0
&& (input_section->flags & SEC_READONLY) != 0
- && h != NULL)
+ && h != NULL
+ && ((bfd_link_executable (info)
+ && h->root.type == bfd_link_hash_undefweak
+ && !resolved_to_zero)
+ || (bfd_link_pic (info)
+ && !(bfd_link_pie (info)
+ && h->root.type == bfd_link_hash_undefined))))
{
bfd_boolean fail = FALSE;
bfd_boolean branch
defined locally or for a branch. */
fail = !h->def_regular && !branch;
}
- else
+ else if (!(bfd_link_pie (info)
+ && (h->needs_copy || eh->needs_copy)))
{
- /* Symbol isn't referenced locally. We only allow
- branch to symbol with non-default visibility. */
+ /* Symbol doesn't need copy reloc and isn't referenced
+ locally. We only allow branch to symbol with
+ non-default visibility. */
fail = (!branch
|| ELF_ST_VISIBILITY (h->other) == STV_DEFAULT);
}
if (fail)
- {
- const char *fmt;
- const char *v;
- const char *pic = "";
-
- switch (ELF_ST_VISIBILITY (h->other))
- {
- case STV_HIDDEN:
- v = _("hidden symbol");
- break;
- case STV_INTERNAL:
- v = _("internal symbol");
- break;
- case STV_PROTECTED:
- v = _("protected symbol");
- break;
- default:
- v = _("symbol");
- pic = _("; recompile with -fPIC");
- break;
- }
-
- if (h->def_regular)
- fmt = _("%B: relocation %s against %s `%s' can not be used when making a shared object%s");
- else
- fmt = _("%B: relocation %s against undefined %s `%s' can not be used when making a shared object%s");
-
- (*_bfd_error_handler) (fmt, input_bfd,
- x86_64_elf_howto_table[r_type].name,
- v, h->root.root.string, pic);
- bfd_set_error (bfd_error_bad_value);
- return FALSE;
- }
+ return elf_x86_64_need_pic (input_bfd, h, howto);
}
/* Fall through. */
if ((input_section->flags & SEC_ALLOC) == 0)
break;
- if ((info->shared
+ /* Don't copy a pc-relative relocation into the output file
+ if the symbol needs copy reloc or the symbol is undefined
+ when building executable. Copy dynamic function pointer
+ relocations. Don't generate dynamic relocations against
+ resolved undefined weak symbols in PIE. */
+ if ((bfd_link_pic (info)
+ && !(bfd_link_pie (info)
+ && h != NULL
+ && (h->needs_copy
+ || eh->needs_copy
+ || h->root.type == bfd_link_hash_undefined)
+ && IS_X86_64_PCREL_TYPE (r_type))
&& (h == NULL
- || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
- || h->root.type != bfd_link_hash_undefweak)
+ || ((ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
+ && !resolved_to_zero)
+ || h->root.type != bfd_link_hash_undefweak))
&& ((! IS_X86_64_PCREL_TYPE (r_type)
&& r_type != R_X86_64_SIZE32
&& r_type != R_X86_64_SIZE64)
|| ! SYMBOL_CALLS_LOCAL (info, h)))
|| (ELIMINATE_COPY_RELOCS
- && !info->shared
+ && !bfd_link_pic (info)
&& h != NULL
&& h->dynindx != -1
- && !h->non_got_ref
- && ((h->def_dynamic
- && !h->def_regular)
- || h->root.type == bfd_link_hash_undefweak
+ && (!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)
+ /* Undefined weak symbol is bound locally when
+ PIC is false. */
|| h->root.type == bfd_link_hash_undefined)))
{
Elf_Internal_Rela outrel;
else if (h != NULL
&& h->dynindx != -1
&& (IS_X86_64_PCREL_TYPE (r_type)
- || ! info->shared
- || ! SYMBOLIC_BIND (info, h)
+ || !(bfd_link_executable (info)
+ || SYMBOLIC_BIND (info, h))
|| ! h->def_regular))
{
+ if ((r_type != R_X86_64_PC64 && r_type != R_X86_64_64)
+ && bfd_link_executable (info)
+ && h->root.type == bfd_link_hash_undefweak
+ && !resolved_to_zero)
+ return elf_x86_64_need_pic (input_bfd, h, howto);
outrel.r_info = htab->r_info (h->dynindx, r_type);
outrel.r_addend = rel->r_addend;
}
else
{
- /* This symbol is local, or marked to become local. */
- if (r_type == htab->pointer_r_type)
+ /* This symbol is local, or marked to become local.
+ When relocation overflow check is disabled, we
+ convert R_X86_64_32 to dynamic R_X86_64_RELATIVE. */
+ if (r_type == htab->pointer_r_type
+ || (r_type == R_X86_64_32
+ && info->no_reloc_overflow_check))
{
relocate = TRUE;
outrel.r_info = htab->r_info (0, R_X86_64_RELATIVE);
"symbol `%s' at 0x%lx in section `%A' is "
"out of range"),
input_bfd, input_section, addend,
- x86_64_elf_howto_table[r_type].name,
- name, (unsigned long) rel->r_offset);
+ howto->name, name,
+ (unsigned long) rel->r_offset);
else
(*_bfd_error_handler)
(_("%B: addend 0x%x in relocation %s against "
"symbol `%s' at 0x%lx in section `%A' is "
"out of range"),
input_bfd, input_section, addend,
- x86_64_elf_howto_table[r_type].name,
- name, (unsigned long) rel->r_offset);
+ howto->name, name,
+ (unsigned long) rel->r_offset);
bfd_set_error (bfd_error_bad_value);
return FALSE;
}
contents + roff + 8 + largepic);
/* Skip R_X86_64_PC32/R_X86_64_PLT32/R_X86_64_PLTOFF64. */
rel++;
+ wrel++;
continue;
}
else if (ELF32_R_TYPE (rel->r_info) == R_X86_64_GOTPC32_TLSDESC)
contents + roff + 8 + largepic);
/* Skip R_X86_64_PLT32/R_X86_64_PLTOFF64. */
rel++;
+ wrel++;
continue;
}
else if (ELF32_R_TYPE (rel->r_info) == R_X86_64_GOTPC32_TLSDESC)
"\x0f\x1f\x40\x00\x64\x8b\x04\x25\0\0\0", 12);
/* Skip R_X86_64_PC32/R_X86_64_PLT32/R_X86_64_PLTOFF64. */
rel++;
+ wrel++;
continue;
}
break;
case R_X86_64_DTPOFF32:
- if (!info->executable|| (input_section->flags & SEC_CODE) == 0)
+ if (!bfd_link_executable (info)
+ || (input_section->flags & SEC_CODE) == 0)
relocation -= elf_x86_64_dtpoff_base (info);
else
relocation = elf_x86_64_tpoff (info, relocation);
case R_X86_64_TPOFF32:
case R_X86_64_TPOFF64:
- BFD_ASSERT (info->executable);
+ BFD_ASSERT (bfd_link_executable (info));
relocation = elf_x86_64_tpoff (info, relocation);
break;
return FALSE;
}
}
+
+ if (wrel != rel)
+ *wrel = *rel;
+ }
+
+ if (wrel != rel)
+ {
+ Elf_Internal_Shdr *rel_hdr;
+ size_t deleted = rel - wrel;
+
+ rel_hdr = _bfd_elf_single_rel_hdr (input_section->output_section);
+ rel_hdr->sh_size -= rel_hdr->sh_entsize * deleted;
+ if (rel_hdr->sh_size == 0)
+ {
+ /* It is too late to remove an empty reloc section. Leave
+ one NONE reloc.
+ ??? What is wrong with an empty section??? */
+ rel_hdr->sh_size = rel_hdr->sh_entsize;
+ deleted -= 1;
+ }
+ rel_hdr = _bfd_elf_single_rel_hdr (input_section);
+ rel_hdr->sh_size -= rel_hdr->sh_entsize * deleted;
+ input_section->reloc_count -= deleted;
}
return TRUE;
elf_x86_64_finish_dynamic_symbol (bfd *output_bfd,
struct bfd_link_info *info,
struct elf_link_hash_entry *h,
- Elf_Internal_Sym *sym ATTRIBUTE_UNUSED)
+ Elf_Internal_Sym *sym)
{
struct elf_x86_64_link_hash_table *htab;
const struct elf_x86_64_backend_data *abed;
bfd_boolean use_plt_bnd;
struct elf_x86_64_link_hash_entry *eh;
+ bfd_boolean local_undefweak;
htab = elf_x86_64_hash_table (info);
if (htab == NULL)
eh = (struct elf_x86_64_link_hash_entry *) h;
+ /* We keep PLT/GOT entries without dynamic PLT/GOT relocations for
+ resolved undefined weak symbols in executable so that their
+ references have value 0 at run-time. */
+ local_undefweak = UNDEFINED_WEAK_RESOLVED_TO_ZERO (info, eh);
+
if (h->plt.offset != (bfd_vma) -1)
{
bfd_vma plt_index;
/* This symbol has an entry in the procedure linkage table. Set
it up. */
if ((h->dynindx == -1
- && !((h->forced_local || info->executable)
+ && !local_undefweak
+ && !((h->forced_local || bfd_link_executable (info))
&& h->def_regular
&& h->type == STT_GNU_IFUNC))
|| plt == NULL
resolved_plt->contents + plt_offset + plt_got_offset);
/* Fill in the entry in the global offset table, initially this
- points to the second part of the PLT entry. */
- bfd_put_64 (output_bfd, (plt->output_section->vma
- + plt->output_offset
- + h->plt.offset + abed->plt_lazy_offset),
- gotplt->contents + got_offset);
-
- /* Fill in the entry in the .rela.plt section. */
- rela.r_offset = (gotplt->output_section->vma
- + gotplt->output_offset
- + got_offset);
- if (h->dynindx == -1
- || ((info->executable
- || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
- && h->def_regular
- && h->type == STT_GNU_IFUNC))
- {
- /* If an STT_GNU_IFUNC symbol is locally defined, generate
- R_X86_64_IRELATIVE instead of R_X86_64_JUMP_SLOT. */
- rela.r_info = htab->r_info (0, R_X86_64_IRELATIVE);
- rela.r_addend = (h->root.u.def.value
- + h->root.u.def.section->output_section->vma
- + h->root.u.def.section->output_offset);
- /* R_X86_64_IRELATIVE comes last. */
- plt_index = htab->next_irelative_index--;
- }
- else
+ points to the second part of the PLT entry. Leave the entry
+ as zero for undefined weak symbol in PIE. No PLT relocation
+ against undefined weak symbol in PIE. */
+ if (!local_undefweak)
{
- rela.r_info = htab->r_info (h->dynindx, R_X86_64_JUMP_SLOT);
- rela.r_addend = 0;
- plt_index = htab->next_jump_slot_index++;
- }
+ bfd_put_64 (output_bfd, (plt->output_section->vma
+ + plt->output_offset
+ + h->plt.offset
+ + abed->plt_lazy_offset),
+ gotplt->contents + got_offset);
+
+ /* Fill in the entry in the .rela.plt section. */
+ rela.r_offset = (gotplt->output_section->vma
+ + gotplt->output_offset
+ + got_offset);
+ if (h->dynindx == -1
+ || ((bfd_link_executable (info)
+ || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
+ && h->def_regular
+ && h->type == STT_GNU_IFUNC))
+ {
+ /* If an STT_GNU_IFUNC symbol is locally defined, generate
+ R_X86_64_IRELATIVE instead of R_X86_64_JUMP_SLOT. */
+ rela.r_info = htab->r_info (0, R_X86_64_IRELATIVE);
+ rela.r_addend = (h->root.u.def.value
+ + h->root.u.def.section->output_section->vma
+ + h->root.u.def.section->output_offset);
+ /* R_X86_64_IRELATIVE comes last. */
+ plt_index = htab->next_irelative_index--;
+ }
+ else
+ {
+ rela.r_info = htab->r_info (h->dynindx, R_X86_64_JUMP_SLOT);
+ rela.r_addend = 0;
+ plt_index = htab->next_jump_slot_index++;
+ }
- /* Don't fill PLT entry for static executables. */
- if (plt == htab->elf.splt)
- {
- bfd_vma plt0_offset = h->plt.offset + plt_plt_insn_end;
-
- /* Put relocation index. */
- bfd_put_32 (output_bfd, plt_index,
- plt->contents + h->plt.offset + abed->plt_reloc_offset);
-
- /* Put offset for jmp .PLT0 and check for overflow. We don't
- check relocation index for overflow since branch displacement
- will overflow first. */
- if (plt0_offset > 0x80000000)
- info->callbacks->einfo (_("%F%B: branch displacement overflow in PLT entry for `%s'\n"),
- output_bfd, h->root.root.string);
- bfd_put_32 (output_bfd, - plt0_offset,
- plt->contents + h->plt.offset + plt_plt_offset);
- }
+ /* Don't fill PLT entry for static executables. */
+ if (plt == htab->elf.splt)
+ {
+ bfd_vma plt0_offset = h->plt.offset + plt_plt_insn_end;
+
+ /* Put relocation index. */
+ bfd_put_32 (output_bfd, plt_index,
+ (plt->contents + h->plt.offset
+ + abed->plt_reloc_offset));
+
+ /* Put offset for jmp .PLT0 and check for overflow. We don't
+ check relocation index for overflow since branch displacement
+ will overflow first. */
+ if (plt0_offset > 0x80000000)
+ info->callbacks->einfo (_("%F%B: branch displacement overflow in PLT entry for `%s'\n"),
+ output_bfd, h->root.root.string);
+ bfd_put_32 (output_bfd, - plt0_offset,
+ plt->contents + h->plt.offset + plt_plt_offset);
+ }
- bed = get_elf_backend_data (output_bfd);
- loc = relplt->contents + plt_index * bed->s->sizeof_rela;
- bed->s->swap_reloca_out (output_bfd, &rela, loc);
+ bed = get_elf_backend_data (output_bfd);
+ loc = relplt->contents + plt_index * bed->s->sizeof_rela;
+ bed->s->swap_reloca_out (output_bfd, &rela, loc);
+ }
}
else if (eh->plt_got.offset != (bfd_vma) -1)
{
plt->contents + plt_offset + plt_got_offset);
}
- if (!h->def_regular
+ if (!local_undefweak
+ && !h->def_regular
&& (h->plt.offset != (bfd_vma) -1
|| eh->plt_got.offset != (bfd_vma) -1))
{
sym->st_value = 0;
}
+ /* Don't generate dynamic GOT relocation against undefined weak
+ symbol in executable. */
if (h->got.offset != (bfd_vma) -1
&& ! GOT_TLS_GD_ANY_P (elf_x86_64_hash_entry (h)->tls_type)
- && elf_x86_64_hash_entry (h)->tls_type != GOT_TLS_IE)
+ && elf_x86_64_hash_entry (h)->tls_type != GOT_TLS_IE
+ && !local_undefweak)
{
Elf_Internal_Rela rela;
if (h->def_regular
&& h->type == STT_GNU_IFUNC)
{
- if (info->shared)
+ if (bfd_link_pic (info))
{
/* Generate R_X86_64_GLOB_DAT. */
goto do_glob_dat;
return TRUE;
}
}
- else if (info->shared
+ else if (bfd_link_pic (info)
&& SYMBOL_REFERENCES_LOCAL (info, h))
{
if (!h->def_regular)
info, h, NULL);
}
+/* Finish up undefined weak symbol handling in PIE. Fill its PLT entry
+ here since undefined weak symbol may not be dynamic and may not be
+ called for elf_x86_64_finish_dynamic_symbol. */
+
+static bfd_boolean
+elf_x86_64_pie_finish_undefweak_symbol (struct bfd_hash_entry *bh,
+ void *inf)
+{
+ struct elf_link_hash_entry *h = (struct elf_link_hash_entry *) bh;
+ struct bfd_link_info *info = (struct bfd_link_info *) inf;
+
+ if (h->root.type != bfd_link_hash_undefweak
+ || h->dynindx != -1)
+ return TRUE;
+
+ return elf_x86_64_finish_dynamic_symbol (info->output_bfd,
+ info, h, NULL);
+}
+
/* Used to decide how to sort relocs in an optimal manner for the
dynamic linker, before writing them out. */
static enum elf_reloc_type_class
-elf_x86_64_reloc_type_class (const struct bfd_link_info *info ATTRIBUTE_UNUSED,
+elf_x86_64_reloc_type_class (const struct bfd_link_info *info,
const asection *rel_sec ATTRIBUTE_UNUSED,
const Elf_Internal_Rela *rela)
{
+ bfd *abfd = info->output_bfd;
+ const struct elf_backend_data *bed = get_elf_backend_data (abfd);
+ struct elf_x86_64_link_hash_table *htab = elf_x86_64_hash_table (info);
+
+ if (htab->elf.dynsym != NULL
+ && htab->elf.dynsym->contents != NULL)
+ {
+ /* Check relocation against STT_GNU_IFUNC symbol if there are
+ dynamic symbols. */
+ unsigned long r_symndx = htab->r_sym (rela->r_info);
+ Elf_Internal_Sym sym;
+ if (!bed->s->swap_symbol_in (abfd,
+ (htab->elf.dynsym->contents
+ + r_symndx * bed->s->sizeof_sym),
+ 0, &sym))
+ abort ();
+
+ if (ELF_ST_TYPE (sym.st_info) == STT_GNU_IFUNC)
+ return reloc_class_ifunc;
+ }
+
switch ((int) ELF32_R_TYPE (rela->r_info))
{
case R_X86_64_RELATIVE:
elf_x86_64_finish_local_dynamic_symbol,
info);
+ /* Fill PLT entries for undefined weak symbols in PIE. */
+ if (bfd_link_pie (info))
+ bfd_hash_traverse (&info->hash->table,
+ elf_x86_64_pie_finish_undefweak_symbol,
+ info);
+
return TRUE;
}
-/* Return address in section PLT for the Ith GOTPLT relocation, for
- relocation REL or (bfd_vma) -1 if it should not be included. */
+/* Return an array of PLT entry symbol values. */
-static bfd_vma
-elf_x86_64_plt_sym_val (bfd_vma i, const asection *plt,
- const arelent *rel)
+static bfd_vma *
+elf_x86_64_get_plt_sym_val (bfd *abfd, asymbol **dynsyms, asection *plt,
+ asection *relplt)
{
- bfd *abfd;
- const struct elf_x86_64_backend_data *bed;
+ bfd_boolean (*slurp_relocs) (bfd *, asection *, asymbol **, bfd_boolean);
+ arelent *p;
+ long count, i;
+ bfd_vma *plt_sym_val;
bfd_vma plt_offset;
+ bfd_byte *plt_contents;
+ const struct elf_x86_64_backend_data *bed;
+ Elf_Internal_Shdr *hdr;
+ asection *plt_bnd;
- /* Only match R_X86_64_JUMP_SLOT and R_X86_64_IRELATIVE. */
- if (rel->howto->type != R_X86_64_JUMP_SLOT
- && rel->howto->type != R_X86_64_IRELATIVE)
- return (bfd_vma) -1;
-
- abfd = plt->owner;
- bed = get_elf_x86_64_backend_data (abfd);
- plt_offset = bed->plt_entry_size;
-
- if (elf_elfheader (abfd)->e_ident[EI_OSABI] != ELFOSABI_GNU)
- return plt->vma + (i + 1) * plt_offset;
+ /* Get the .plt section contents. PLT passed down may point to the
+ .plt.bnd section. Make sure that PLT always points to the .plt
+ section. */
+ plt_bnd = bfd_get_section_by_name (abfd, ".plt.bnd");
+ if (plt_bnd)
+ {
+ if (plt != plt_bnd)
+ abort ();
+ plt = bfd_get_section_by_name (abfd, ".plt");
+ if (plt == NULL)
+ abort ();
+ bed = &elf_x86_64_bnd_arch_bed;
+ }
+ else
+ bed = get_elf_x86_64_backend_data (abfd);
- while (plt_offset < plt->size)
+ plt_contents = (bfd_byte *) bfd_malloc (plt->size);
+ if (plt_contents == NULL)
+ return NULL;
+ if (!bfd_get_section_contents (abfd, (asection *) plt,
+ plt_contents, 0, plt->size))
{
- bfd_vma reloc_index;
- bfd_byte reloc_index_raw[4];
-
- if (!bfd_get_section_contents (abfd, (asection *) plt,
- reloc_index_raw,
- plt_offset + bed->plt_reloc_offset,
- sizeof (reloc_index_raw)))
- return (bfd_vma) -1;
-
- reloc_index = H_GET_32 (abfd, reloc_index_raw);
- if (reloc_index == i)
- return plt->vma + plt_offset;
- plt_offset += bed->plt_entry_size;
+bad_return:
+ free (plt_contents);
+ return NULL;
}
- abort ();
-}
+ slurp_relocs = get_elf_backend_data (abfd)->s->slurp_reloc_table;
+ if (! (*slurp_relocs) (abfd, relplt, dynsyms, TRUE))
+ goto bad_return;
-/* Return offset in .plt.bnd section for the Ith GOTPLT relocation with
- PLT section, or (bfd_vma) -1 if it should not be included. */
+ hdr = &elf_section_data (relplt)->this_hdr;
+ count = relplt->size / hdr->sh_entsize;
-static bfd_vma
-elf_x86_64_plt_sym_val_offset_plt_bnd (bfd_vma i, const asection *plt)
-{
- const struct elf_x86_64_backend_data *bed = &elf_x86_64_bnd_arch_bed;
- bfd *abfd = plt->owner;
- bfd_vma plt_offset = bed->plt_entry_size;
+ plt_sym_val = (bfd_vma *) bfd_malloc (sizeof (bfd_vma) * count);
+ if (plt_sym_val == NULL)
+ goto bad_return;
- if (elf_elfheader (abfd)->e_ident[EI_OSABI] != ELFOSABI_GNU)
- return i * sizeof (elf_x86_64_legacy_plt2_entry);
+ for (i = 0; i < count; i++)
+ plt_sym_val[i] = -1;
- while (plt_offset < plt->size)
+ plt_offset = bed->plt_entry_size;
+ p = relplt->relocation;
+ for (i = 0; i < count; i++, p++)
{
- bfd_vma reloc_index;
- bfd_byte reloc_index_raw[4];
+ long reloc_index;
- if (!bfd_get_section_contents (abfd, (asection *) plt,
- reloc_index_raw,
- plt_offset + bed->plt_reloc_offset,
- sizeof (reloc_index_raw)))
- return (bfd_vma) -1;
+ /* Skip unknown relocation. */
+ if (p->howto == NULL)
+ continue;
- reloc_index = H_GET_32 (abfd, reloc_index_raw);
- if (reloc_index == i)
+ if (p->howto->type != R_X86_64_JUMP_SLOT
+ && p->howto->type != R_X86_64_IRELATIVE)
+ continue;
+
+ reloc_index = H_GET_32 (abfd, (plt_contents + plt_offset
+ + bed->plt_reloc_offset));
+ if (reloc_index < count)
{
- /* This is the index in .plt section. */
- long plt_index = plt_offset / bed->plt_entry_size;
- /* Return the offset in .plt.bnd section. */
- return (plt_index - 1) * sizeof (elf_x86_64_legacy_plt2_entry);
+ if (plt_bnd)
+ {
+ /* This is the index in .plt section. */
+ long plt_index = plt_offset / bed->plt_entry_size;
+ /* Store VMA + the offset in .plt.bnd section. */
+ plt_sym_val[reloc_index] =
+ (plt_bnd->vma
+ + (plt_index - 1) * sizeof (elf_x86_64_legacy_plt2_entry));
+ }
+ else
+ plt_sym_val[reloc_index] = plt->vma + plt_offset;
}
plt_offset += bed->plt_entry_size;
+
+ /* PR binutils/18437: Skip extra relocations in the .rela.plt
+ section. */
+ if (plt_offset >= plt->size)
+ break;
}
- abort ();
+ free (plt_contents);
+
+ return plt_sym_val;
}
/* Similar to _bfd_elf_get_synthetic_symtab, with .plt.bnd section
asymbol **dynsyms,
asymbol **ret)
{
- const struct elf_backend_data *bed = get_elf_backend_data (abfd);
- asection *relplt;
- asymbol *s;
- bfd_boolean (*slurp_relocs) (bfd *, asection *, asymbol **, bfd_boolean);
- arelent *p;
- long count, i, n;
- size_t size;
- Elf_Internal_Shdr *hdr;
- char *names;
- asection *plt, *plt_push;
-
- plt_push = bfd_get_section_by_name (abfd, ".plt");
- if (plt_push == NULL)
- return 0;
-
- plt = bfd_get_section_by_name (abfd, ".plt.bnd");
- /* Use the generic ELF version if there is no .plt.bnd section. */
+ /* Pass the .plt.bnd section to _bfd_elf_ifunc_get_synthetic_symtab
+ as PLT if it exists. */
+ asection *plt = bfd_get_section_by_name (abfd, ".plt.bnd");
if (plt == NULL)
- return _bfd_elf_get_synthetic_symtab (abfd, symcount, syms,
- dynsymcount, dynsyms, ret);
-
- *ret = NULL;
-
- if ((abfd->flags & (DYNAMIC | EXEC_P)) == 0)
- return 0;
-
- if (dynsymcount <= 0)
- return 0;
-
- relplt = bfd_get_section_by_name (abfd, ".rela.plt");
- 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)
- size += sizeof ("+0x") - 1 + 8 + 8;
- }
-
- s = *ret = (asymbol *) bfd_malloc (size);
- if (s == NULL)
- return -1;
-
- names = (char *) (s + count);
- p = relplt->relocation;
- n = 0;
- for (i = 0; i < count; i++, p++)
- {
- bfd_vma offset;
- size_t len;
-
- if (p->howto->type != R_X86_64_JUMP_SLOT
- && p->howto->type != R_X86_64_IRELATIVE)
- continue;
-
- offset = elf_x86_64_plt_sym_val_offset_plt_bnd (i, plt_push);
-
- *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 = offset;
- 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;
- }
-
- return n;
+ plt = bfd_get_section_by_name (abfd, ".plt");
+ return _bfd_elf_ifunc_get_synthetic_symtab (abfd, symcount, syms,
+ dynsymcount, dynsyms, ret,
+ plt,
+ elf_x86_64_get_plt_sym_val);
}
/* Handle an x86-64 specific section when reading an object file. This
return TRUE;
}
- if ((ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC
- || ELF_ST_BIND (sym->st_info) == STB_GNU_UNIQUE)
+ if (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;
+ elf_tdata (info->output_bfd)->has_gnu_symbols
+ |= elf_gnu_symbol_unique;
return TRUE;
}
#define elf_backend_got_header_size (GOT_ENTRY_SIZE*3)
#define elf_backend_rela_normal 1
#define elf_backend_plt_alignment 4
+#define elf_backend_extern_protected_data 1
#define elf_info_to_howto elf_x86_64_info_to_howto
#define elf_backend_size_dynamic_sections elf_x86_64_size_dynamic_sections
#define elf_backend_always_size_sections elf_x86_64_always_size_sections
#define elf_backend_init_index_section _bfd_elf_init_1_index_section
-#define elf_backend_plt_sym_val elf_x86_64_plt_sym_val
#define elf_backend_object_p elf64_x86_64_elf_object_p
#define bfd_elf64_mkobject elf_x86_64_mkobject
#define bfd_elf64_get_synthetic_symtab elf_x86_64_get_synthetic_symtab
elf_x86_64_additional_program_headers
#define elf_backend_hash_symbol \
elf_x86_64_hash_symbol
+#define elf_backend_omit_section_dynsym \
+ ((bfd_boolean (*) (bfd *, struct bfd_link_info *, asection *)) bfd_true)
+#define elf_backend_fixup_symbol \
+ elf_x86_64_fixup_symbol
+
+#include "elf64-target.h"
+
+/* CloudABI support. */
+
+#undef TARGET_LITTLE_SYM
+#define TARGET_LITTLE_SYM x86_64_elf64_cloudabi_vec
+#undef TARGET_LITTLE_NAME
+#define TARGET_LITTLE_NAME "elf64-x86-64-cloudabi"
+
+#undef ELF_OSABI
+#define ELF_OSABI ELFOSABI_CLOUDABI
+
+#undef elf64_bed
+#define elf64_bed elf64_x86_64_cloudabi_bed
#include "elf64-target.h"
#include "elf64-target.h"
-#undef bfd_elf64_get_synthetic_symtab
-
/* Native Client support. */
static bfd_boolean
elf_x86_64_reloc_name_lookup
#define bfd_elf32_mkobject \
elf_x86_64_mkobject
+#define bfd_elf32_get_synthetic_symtab \
+ elf_x86_64_get_synthetic_symtab
#undef elf_backend_object_p
#define elf_backend_object_p \
projects / binutils-gdb.git / blobdiff