blob: a29ba8a324c3adbff9fe5969b7d09d88e9c7a65b [file] [log] [blame]
/* X86-64 specific support for ELF
Copyright 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
2010, 2011, 2012
Free Software Foundation, Inc.
Contributed by Jan Hubicka <jh@suse.cz>.
This file is part of BFD, the Binary File Descriptor library.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
MA 02110-1301, USA. */
#include "sysdep.h"
#include "bfd.h"
#include "bfdlink.h"
#include "libbfd.h"
#include "elf-bfd.h"
#include "elf-nacl.h"
#include "bfd_stdint.h"
#include "objalloc.h"
#include "hashtab.h"
#include "dwarf2.h"
#include "libiberty.h"
#include "elf/x86-64.h"
#ifdef CORE_HEADER
#include <stdarg.h>
#include CORE_HEADER
#endif
/* In case we're on a 32-bit machine, construct a 64-bit "-1" value. */
#define MINUS_ONE (~ (bfd_vma) 0)
/* Since both 32-bit and 64-bit x86-64 encode relocation type in the
identical manner, we use ELF32_R_TYPE instead of ELF64_R_TYPE to get
relocation type. We also use ELF_ST_TYPE instead of ELF64_ST_TYPE
since they are the same. */
#define ABI_64_P(abfd) \
(get_elf_backend_data (abfd)->s->elfclass == ELFCLASS64)
/* The relocation "howto" table. Order of fields:
type, rightshift, size, bitsize, pc_relative, bitpos, complain_on_overflow,
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,
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,
bfd_elf_generic_reloc, "R_X86_64_64", FALSE, MINUS_ONE, MINUS_ONE,
FALSE),
HOWTO(R_X86_64_PC32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_PC32", FALSE, 0xffffffff, 0xffffffff,
TRUE),
HOWTO(R_X86_64_GOT32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_GOT32", FALSE, 0xffffffff, 0xffffffff,
FALSE),
HOWTO(R_X86_64_PLT32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_PLT32", FALSE, 0xffffffff, 0xffffffff,
TRUE),
HOWTO(R_X86_64_COPY, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
bfd_elf_generic_reloc, "R_X86_64_COPY", FALSE, 0xffffffff, 0xffffffff,
FALSE),
HOWTO(R_X86_64_GLOB_DAT, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
bfd_elf_generic_reloc, "R_X86_64_GLOB_DAT", FALSE, MINUS_ONE,
MINUS_ONE, FALSE),
HOWTO(R_X86_64_JUMP_SLOT, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
bfd_elf_generic_reloc, "R_X86_64_JUMP_SLOT", FALSE, MINUS_ONE,
MINUS_ONE, FALSE),
HOWTO(R_X86_64_RELATIVE, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
bfd_elf_generic_reloc, "R_X86_64_RELATIVE", FALSE, MINUS_ONE,
MINUS_ONE, FALSE),
HOWTO(R_X86_64_GOTPCREL, 0, 2, 32, TRUE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_GOTPCREL", FALSE, 0xffffffff,
0xffffffff, TRUE),
HOWTO(R_X86_64_32, 0, 2, 32, FALSE, 0, complain_overflow_unsigned,
bfd_elf_generic_reloc, "R_X86_64_32", FALSE, 0xffffffff, 0xffffffff,
FALSE),
HOWTO(R_X86_64_32S, 0, 2, 32, FALSE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_32S", FALSE, 0xffffffff, 0xffffffff,
FALSE),
HOWTO(R_X86_64_16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield,
bfd_elf_generic_reloc, "R_X86_64_16", FALSE, 0xffff, 0xffff, FALSE),
HOWTO(R_X86_64_PC16,0, 1, 16, TRUE, 0, complain_overflow_bitfield,
bfd_elf_generic_reloc, "R_X86_64_PC16", FALSE, 0xffff, 0xffff, TRUE),
HOWTO(R_X86_64_8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield,
bfd_elf_generic_reloc, "R_X86_64_8", FALSE, 0xff, 0xff, FALSE),
HOWTO(R_X86_64_PC8, 0, 0, 8, TRUE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_PC8", FALSE, 0xff, 0xff, TRUE),
HOWTO(R_X86_64_DTPMOD64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
bfd_elf_generic_reloc, "R_X86_64_DTPMOD64", FALSE, MINUS_ONE,
MINUS_ONE, FALSE),
HOWTO(R_X86_64_DTPOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
bfd_elf_generic_reloc, "R_X86_64_DTPOFF64", FALSE, MINUS_ONE,
MINUS_ONE, FALSE),
HOWTO(R_X86_64_TPOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
bfd_elf_generic_reloc, "R_X86_64_TPOFF64", FALSE, MINUS_ONE,
MINUS_ONE, FALSE),
HOWTO(R_X86_64_TLSGD, 0, 2, 32, TRUE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_TLSGD", FALSE, 0xffffffff,
0xffffffff, TRUE),
HOWTO(R_X86_64_TLSLD, 0, 2, 32, TRUE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_TLSLD", FALSE, 0xffffffff,
0xffffffff, TRUE),
HOWTO(R_X86_64_DTPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_DTPOFF32", FALSE, 0xffffffff,
0xffffffff, FALSE),
HOWTO(R_X86_64_GOTTPOFF, 0, 2, 32, TRUE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_GOTTPOFF", FALSE, 0xffffffff,
0xffffffff, TRUE),
HOWTO(R_X86_64_TPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_TPOFF32", FALSE, 0xffffffff,
0xffffffff, FALSE),
HOWTO(R_X86_64_PC64, 0, 4, 64, TRUE, 0, complain_overflow_bitfield,
bfd_elf_generic_reloc, "R_X86_64_PC64", FALSE, MINUS_ONE, MINUS_ONE,
TRUE),
HOWTO(R_X86_64_GOTOFF64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
bfd_elf_generic_reloc, "R_X86_64_GOTOFF64",
FALSE, MINUS_ONE, MINUS_ONE, FALSE),
HOWTO(R_X86_64_GOTPC32, 0, 2, 32, TRUE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_GOTPC32",
FALSE, 0xffffffff, 0xffffffff, TRUE),
HOWTO(R_X86_64_GOT64, 0, 4, 64, FALSE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_GOT64", FALSE, MINUS_ONE, MINUS_ONE,
FALSE),
HOWTO(R_X86_64_GOTPCREL64, 0, 4, 64, TRUE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_GOTPCREL64", FALSE, MINUS_ONE,
MINUS_ONE, TRUE),
HOWTO(R_X86_64_GOTPC64, 0, 4, 64, TRUE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_GOTPC64",
FALSE, MINUS_ONE, MINUS_ONE, TRUE),
HOWTO(R_X86_64_GOTPLT64, 0, 4, 64, FALSE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_GOTPLT64", FALSE, MINUS_ONE,
MINUS_ONE, FALSE),
HOWTO(R_X86_64_PLTOFF64, 0, 4, 64, FALSE, 0, complain_overflow_signed,
bfd_elf_generic_reloc, "R_X86_64_PLTOFF64", FALSE, MINUS_ONE,
MINUS_ONE, FALSE),
EMPTY_HOWTO (32),
EMPTY_HOWTO (33),
HOWTO(R_X86_64_GOTPC32_TLSDESC, 0, 2, 32, TRUE, 0,
complain_overflow_bitfield, bfd_elf_generic_reloc,
"R_X86_64_GOTPC32_TLSDESC",
FALSE, 0xffffffff, 0xffffffff, TRUE),
HOWTO(R_X86_64_TLSDESC_CALL, 0, 0, 0, FALSE, 0,
complain_overflow_dont, bfd_elf_generic_reloc,
"R_X86_64_TLSDESC_CALL",
FALSE, 0, 0, FALSE),
HOWTO(R_X86_64_TLSDESC, 0, 4, 64, FALSE, 0,
complain_overflow_bitfield, bfd_elf_generic_reloc,
"R_X86_64_TLSDESC",
FALSE, MINUS_ONE, MINUS_ONE, FALSE),
HOWTO(R_X86_64_IRELATIVE, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
bfd_elf_generic_reloc, "R_X86_64_IRELATIVE", FALSE, MINUS_ONE,
MINUS_ONE, FALSE),
HOWTO(R_X86_64_RELATIVE64, 0, 4, 64, FALSE, 0, complain_overflow_bitfield,
bfd_elf_generic_reloc, "R_X86_64_RELATIVE64", FALSE, MINUS_ONE,
MINUS_ONE, FALSE),
/* 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_IRELATIVE + 1)
#define R_X86_64_vt_offset (R_X86_64_GNU_VTINHERIT - R_X86_64_standard)
/* GNU extension to record C++ vtable hierarchy. */
HOWTO (R_X86_64_GNU_VTINHERIT, 0, 4, 0, FALSE, 0, complain_overflow_dont,
NULL, "R_X86_64_GNU_VTINHERIT", FALSE, 0, 0, FALSE),
/* GNU extension to record C++ vtable member usage. */
HOWTO (R_X86_64_GNU_VTENTRY, 0, 4, 0, FALSE, 0, complain_overflow_dont,
_bfd_elf_rel_vtable_reloc_fn, "R_X86_64_GNU_VTENTRY", FALSE, 0, 0,
FALSE),
/* Use complain_overflow_bitfield on R_X86_64_32 for x32. */
HOWTO(R_X86_64_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
bfd_elf_generic_reloc, "R_X86_64_32", FALSE, 0xffffffff, 0xffffffff,
FALSE)
};
#define IS_X86_64_PCREL_TYPE(TYPE) \
( ((TYPE) == R_X86_64_PC8) \
|| ((TYPE) == R_X86_64_PC16) \
|| ((TYPE) == R_X86_64_PC32) \
|| ((TYPE) == R_X86_64_PC64))
/* Map BFD relocs to the x86_64 elf relocs. */
struct elf_reloc_map
{
bfd_reloc_code_real_type bfd_reloc_val;
unsigned char elf_reloc_val;
};
static const struct elf_reloc_map x86_64_reloc_map[] =
{
{ BFD_RELOC_NONE, R_X86_64_NONE, },
{ BFD_RELOC_64, R_X86_64_64, },
{ BFD_RELOC_32_PCREL, R_X86_64_PC32, },
{ BFD_RELOC_X86_64_GOT32, R_X86_64_GOT32,},
{ BFD_RELOC_X86_64_PLT32, R_X86_64_PLT32,},
{ BFD_RELOC_X86_64_COPY, R_X86_64_COPY, },
{ BFD_RELOC_X86_64_GLOB_DAT, R_X86_64_GLOB_DAT, },
{ BFD_RELOC_X86_64_JUMP_SLOT, R_X86_64_JUMP_SLOT, },
{ BFD_RELOC_X86_64_RELATIVE, R_X86_64_RELATIVE, },
{ BFD_RELOC_X86_64_GOTPCREL, R_X86_64_GOTPCREL, },
{ BFD_RELOC_32, R_X86_64_32, },
{ BFD_RELOC_X86_64_32S, R_X86_64_32S, },
{ BFD_RELOC_16, R_X86_64_16, },
{ BFD_RELOC_16_PCREL, R_X86_64_PC16, },
{ BFD_RELOC_8, R_X86_64_8, },
{ BFD_RELOC_8_PCREL, R_X86_64_PC8, },
{ BFD_RELOC_X86_64_DTPMOD64, R_X86_64_DTPMOD64, },
{ BFD_RELOC_X86_64_DTPOFF64, R_X86_64_DTPOFF64, },
{ BFD_RELOC_X86_64_TPOFF64, R_X86_64_TPOFF64, },
{ BFD_RELOC_X86_64_TLSGD, R_X86_64_TLSGD, },
{ BFD_RELOC_X86_64_TLSLD, R_X86_64_TLSLD, },
{ BFD_RELOC_X86_64_DTPOFF32, R_X86_64_DTPOFF32, },
{ BFD_RELOC_X86_64_GOTTPOFF, R_X86_64_GOTTPOFF, },
{ BFD_RELOC_X86_64_TPOFF32, R_X86_64_TPOFF32, },
{ BFD_RELOC_64_PCREL, R_X86_64_PC64, },
{ BFD_RELOC_X86_64_GOTOFF64, R_X86_64_GOTOFF64, },
{ BFD_RELOC_X86_64_GOTPC32, R_X86_64_GOTPC32, },
{ BFD_RELOC_X86_64_GOT64, R_X86_64_GOT64, },
{ BFD_RELOC_X86_64_GOTPCREL64,R_X86_64_GOTPCREL64, },
{ BFD_RELOC_X86_64_GOTPC64, R_X86_64_GOTPC64, },
{ BFD_RELOC_X86_64_GOTPLT64, R_X86_64_GOTPLT64, },
{ BFD_RELOC_X86_64_PLTOFF64, R_X86_64_PLTOFF64, },
{ BFD_RELOC_X86_64_GOTPC32_TLSDESC, R_X86_64_GOTPC32_TLSDESC, },
{ 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_VTABLE_INHERIT, R_X86_64_GNU_VTINHERIT, },
{ BFD_RELOC_VTABLE_ENTRY, R_X86_64_GNU_VTENTRY, },
};
static reloc_howto_type *
elf_x86_64_rtype_to_howto (bfd *abfd, unsigned r_type)
{
unsigned i;
if (r_type == (unsigned int) R_X86_64_32)
{
if (ABI_64_P (abfd))
i = r_type;
else
i = ARRAY_SIZE (x86_64_elf_howto_table) - 1;
}
else if (r_type < (unsigned int) R_X86_64_GNU_VTINHERIT
|| r_type >= (unsigned int) R_X86_64_max)
{
if (r_type >= (unsigned int) R_X86_64_standard)
{
(*_bfd_error_handler) (_("%B: invalid relocation type %d"),
abfd, (int) r_type);
r_type = R_X86_64_NONE;
}
i = r_type;
}
else
i = r_type - (unsigned int) R_X86_64_vt_offset;
BFD_ASSERT (x86_64_elf_howto_table[i].type == r_type);
return &x86_64_elf_howto_table[i];
}
/* Given a BFD reloc type, return a HOWTO structure. */
static reloc_howto_type *
elf_x86_64_reloc_type_lookup (bfd *abfd,
bfd_reloc_code_real_type code)
{
unsigned int i;
for (i = 0; i < sizeof (x86_64_reloc_map) / sizeof (struct elf_reloc_map);
i++)
{
if (x86_64_reloc_map[i].bfd_reloc_val == code)
return elf_x86_64_rtype_to_howto (abfd,
x86_64_reloc_map[i].elf_reloc_val);
}
return 0;
}
static reloc_howto_type *
elf_x86_64_reloc_name_lookup (bfd *abfd,
const char *r_name)
{
unsigned int i;
if (!ABI_64_P (abfd) && strcasecmp (r_name, "R_X86_64_32") == 0)
{
/* Get x32 R_X86_64_32. */
reloc_howto_type *reloc
= &x86_64_elf_howto_table[ARRAY_SIZE (x86_64_elf_howto_table) - 1];
BFD_ASSERT (reloc->type == (unsigned int) R_X86_64_32);
return reloc;
}
for (i = 0; i < ARRAY_SIZE (x86_64_elf_howto_table); i++)
if (x86_64_elf_howto_table[i].name != NULL
&& strcasecmp (x86_64_elf_howto_table[i].name, r_name) == 0)
return &x86_64_elf_howto_table[i];
return NULL;
}
/* Given an x86_64 ELF reloc type, fill in an arelent structure. */
static void
elf_x86_64_info_to_howto (bfd *abfd ATTRIBUTE_UNUSED, arelent *cache_ptr,
Elf_Internal_Rela *dst)
{
unsigned r_type;
r_type = ELF32_R_TYPE (dst->r_info);
cache_ptr->howto = elf_x86_64_rtype_to_howto (abfd, r_type);
BFD_ASSERT (r_type == cache_ptr->howto->type);
}
/* Support for core dump NOTE sections. */
static bfd_boolean
elf_x86_64_grok_prstatus (bfd *abfd, Elf_Internal_Note *note)
{
int offset;
size_t size;
switch (note->descsz)
{
default:
return FALSE;
case 296: /* sizeof(istruct elf_prstatus) on Linux/x32 */
/* pr_cursig */
elf_tdata (abfd)->core_signal = bfd_get_16 (abfd, note->descdata + 12);
/* pr_pid */
elf_tdata (abfd)->core_lwpid = bfd_get_32 (abfd, note->descdata + 24);
/* pr_reg */
offset = 72;
size = 216;
break;
case 336: /* sizeof(istruct elf_prstatus) on Linux/x86_64 */
/* pr_cursig */
elf_tdata (abfd)->core_signal
= bfd_get_16 (abfd, note->descdata + 12);
/* pr_pid */
elf_tdata (abfd)->core_lwpid
= bfd_get_32 (abfd, note->descdata + 32);
/* pr_reg */
offset = 112;
size = 216;
break;
}
/* Make a ".reg/999" section. */
return _bfd_elfcore_make_pseudosection (abfd, ".reg",
size, note->descpos + offset);
}
static bfd_boolean
elf_x86_64_grok_psinfo (bfd *abfd, Elf_Internal_Note *note)
{
switch (note->descsz)
{
default:
return FALSE;
case 124: /* sizeof(struct elf_prpsinfo) on Linux/x32 */
elf_tdata (abfd)->core_pid
= bfd_get_32 (abfd, note->descdata + 12);
elf_tdata (abfd)->core_program
= _bfd_elfcore_strndup (abfd, note->descdata + 28, 16);
elf_tdata (abfd)->core_command
= _bfd_elfcore_strndup (abfd, note->descdata + 44, 80);
break;
case 136: /* sizeof(struct elf_prpsinfo) on Linux/x86_64 */
elf_tdata (abfd)->core_pid
= bfd_get_32 (abfd, note->descdata + 24);
elf_tdata (abfd)->core_program
= _bfd_elfcore_strndup (abfd, note->descdata + 40, 16);
elf_tdata (abfd)->core_command
= _bfd_elfcore_strndup (abfd, note->descdata + 56, 80);
}
/* Note that for some reason, a spurious space is tacked
onto the end of the args in some (at least one anyway)
implementations, so strip it off if it exists. */
{
char *command = elf_tdata (abfd)->core_command;
int n = strlen (command);
if (0 < n && command[n - 1] == ' ')
command[n - 1] = '\0';
}
return TRUE;
}
#ifdef CORE_HEADER
static char *
elf_x86_64_write_core_note (bfd *abfd, char *buf, int *bufsiz,
int note_type, ...)
{
const struct elf_backend_data *bed = get_elf_backend_data (abfd);
va_list ap;
const char *fname, *psargs;
long pid;
int cursig;
const void *gregs;
switch (note_type)
{
default:
return NULL;
case NT_PRPSINFO:
va_start (ap, note_type);
fname = va_arg (ap, const char *);
psargs = va_arg (ap, const char *);
va_end (ap);
if (bed->s->elfclass == ELFCLASS32)
{
prpsinfo32_t data;
memset (&data, 0, sizeof (data));
strncpy (data.pr_fname, fname, sizeof (data.pr_fname));
strncpy (data.pr_psargs, psargs, sizeof (data.pr_psargs));
return elfcore_write_note (abfd, buf, bufsiz, "CORE", note_type,
&data, sizeof (data));
}
else
{
prpsinfo_t data;
memset (&data, 0, sizeof (data));
strncpy (data.pr_fname, fname, sizeof (data.pr_fname));
strncpy (data.pr_psargs, psargs, sizeof (data.pr_psargs));
return elfcore_write_note (abfd, buf, bufsiz, "CORE", note_type,
&data, sizeof (data));
}
/* NOTREACHED */
case NT_PRSTATUS:
va_start (ap, note_type);
pid = va_arg (ap, long);
cursig = va_arg (ap, int);
gregs = va_arg (ap, const void *);
va_end (ap);
if (bed->s->elfclass == ELFCLASS32)
{
if (bed->elf_machine_code == EM_X86_64)
{
prstatusx32_t prstat;
memset (&prstat, 0, sizeof (prstat));
prstat.pr_pid = pid;
prstat.pr_cursig = cursig;
memcpy (&prstat.pr_reg, gregs, sizeof (prstat.pr_reg));
return elfcore_write_note (abfd, buf, bufsiz, "CORE", note_type,
&prstat, sizeof (prstat));
}
else
{
prstatus32_t prstat;
memset (&prstat, 0, sizeof (prstat));
prstat.pr_pid = pid;
prstat.pr_cursig = cursig;
memcpy (&prstat.pr_reg, gregs, sizeof (prstat.pr_reg));
return elfcore_write_note (abfd, buf, bufsiz, "CORE", note_type,
&prstat, sizeof (prstat));
}
}
else
{
prstatus_t prstat;
memset (&prstat, 0, sizeof (prstat));
prstat.pr_pid = pid;
prstat.pr_cursig = cursig;
memcpy (&prstat.pr_reg, gregs, sizeof (prstat.pr_reg));
return elfcore_write_note (abfd, buf, bufsiz, "CORE", note_type,
&prstat, sizeof (prstat));
}
}
/* NOTREACHED */
}
#endif
/* Functions for the x86-64 ELF linker. */
/* The name of the dynamic interpreter. This is put in the .interp
section. */
#define ELF64_DYNAMIC_INTERPRETER "/lib/ld64.so.1"
#define ELF32_DYNAMIC_INTERPRETER "/lib/ldx32.so.1"
/* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
copying dynamic variables from a shared lib into an app's dynbss
section, and instead use a dynamic relocation to point into the
shared lib. */
#define ELIMINATE_COPY_RELOCS 1
/* The size in bytes of an entry in the global offset table. */
#define GOT_ENTRY_SIZE 8
/* The size in bytes of an entry in the procedure linkage table. */
#define PLT_ENTRY_SIZE 16
/* The first entry in a procedure linkage table looks like this. See the
SVR4 ABI i386 supplement and the x86-64 ABI to see how this works. */
static const bfd_byte elf_x86_64_plt0_entry[PLT_ENTRY_SIZE] =
{
0xff, 0x35, 8, 0, 0, 0, /* pushq GOT+8(%rip) */
0xff, 0x25, 16, 0, 0, 0, /* jmpq *GOT+16(%rip) */
0x0f, 0x1f, 0x40, 0x00 /* nopl 0(%rax) */
};
/* Subsequent entries in a procedure linkage table look like this. */
static const bfd_byte elf_x86_64_plt_entry[PLT_ENTRY_SIZE] =
{
0xff, 0x25, /* jmpq *name@GOTPC(%rip) */
0, 0, 0, 0, /* replaced with offset to this symbol in .got. */
0x68, /* pushq immediate */
0, 0, 0, 0, /* replaced with index into relocation table. */
0xe9, /* jmp relative */
0, 0, 0, 0 /* replaced with offset to start of .plt0. */
};
/* .eh_frame covering the .plt section. */
static const bfd_byte elf_x86_64_eh_frame_plt[] =
{
#define PLT_CIE_LENGTH 20
#define PLT_FDE_LENGTH 36
#define PLT_FDE_START_OFFSET 4 + PLT_CIE_LENGTH + 8
#define PLT_FDE_LEN_OFFSET 4 + PLT_CIE_LENGTH + 12
PLT_CIE_LENGTH, 0, 0, 0, /* CIE length */
0, 0, 0, 0, /* CIE ID */
1, /* CIE version */
'z', 'R', 0, /* Augmentation string */
1, /* Code alignment factor */
0x78, /* Data alignment factor */
16, /* Return address column */
1, /* Augmentation size */
DW_EH_PE_pcrel | DW_EH_PE_sdata4, /* FDE encoding */
DW_CFA_def_cfa, 7, 8, /* DW_CFA_def_cfa: r7 (rsp) ofs 8 */
DW_CFA_offset + 16, 1, /* DW_CFA_offset: r16 (rip) at cfa-8 */
DW_CFA_nop, DW_CFA_nop,
PLT_FDE_LENGTH, 0, 0, 0, /* FDE length */
PLT_CIE_LENGTH + 8, 0, 0, 0, /* CIE pointer */
0, 0, 0, 0, /* R_X86_64_PC32 .plt goes here */
0, 0, 0, 0, /* .plt size goes here */
0, /* Augmentation size */
DW_CFA_def_cfa_offset, 16, /* DW_CFA_def_cfa_offset: 16 */
DW_CFA_advance_loc + 6, /* DW_CFA_advance_loc: 6 to __PLT__+6 */
DW_CFA_def_cfa_offset, 24, /* DW_CFA_def_cfa_offset: 24 */
DW_CFA_advance_loc + 10, /* DW_CFA_advance_loc: 10 to __PLT__+16 */
DW_CFA_def_cfa_expression, /* DW_CFA_def_cfa_expression */
11, /* Block length */
DW_OP_breg7, 8, /* DW_OP_breg7 (rsp): 8 */
DW_OP_breg16, 0, /* DW_OP_breg16 (rip): 0 */
DW_OP_lit15, DW_OP_and, DW_OP_lit11, DW_OP_ge,
DW_OP_lit3, DW_OP_shl, DW_OP_plus,
DW_CFA_nop, DW_CFA_nop, DW_CFA_nop, DW_CFA_nop
};
/* Architecture-specific backend data for x86-64. */
struct elf_x86_64_backend_data
{
/* Templates for the initial PLT entry and for subsequent entries. */
const bfd_byte *plt0_entry;
const bfd_byte *plt_entry;
unsigned int plt_entry_size; /* Size of each PLT entry. */
/* Offsets into plt0_entry that are to be replaced with GOT[1] and GOT[2]. */
unsigned int plt0_got1_offset;
unsigned int plt0_got2_offset;
/* Offset of the end of the PC-relative instruction containing
plt0_got2_offset. */
unsigned int plt0_got2_insn_end;
/* Offsets into plt_entry that are to be replaced with... */
unsigned int plt_got_offset; /* ... address of this symbol in .got. */
unsigned int plt_reloc_offset; /* ... offset into relocation table. */
unsigned int plt_plt_offset; /* ... offset to start of .plt. */
/* Length of the PC-relative instruction containing plt_got_offset. */
unsigned int plt_got_insn_size;
/* Offset of the end of the PC-relative jump to plt0_entry. */
unsigned int plt_plt_insn_end;
/* Offset into plt_entry where the initial value of the GOT entry points. */
unsigned int plt_lazy_offset;
/* .eh_frame covering the .plt section. */
const bfd_byte *eh_frame_plt;
unsigned int eh_frame_plt_size;
};
#define get_elf_x86_64_backend_data(abfd) \
((const struct elf_x86_64_backend_data *) \
get_elf_backend_data (abfd)->arch_data)
#define GET_PLT_ENTRY_SIZE(abfd) \
get_elf_x86_64_backend_data (abfd)->plt_entry_size
/* These are the standard parameters. */
static const struct elf_x86_64_backend_data elf_x86_64_arch_bed =
{
elf_x86_64_plt0_entry, /* plt0_entry */
elf_x86_64_plt_entry, /* plt_entry */
sizeof (elf_x86_64_plt_entry), /* plt_entry_size */
2, /* plt0_got1_offset */
8, /* plt0_got2_offset */
12, /* plt0_got2_insn_end */
2, /* plt_got_offset */
7, /* plt_reloc_offset */
12, /* plt_plt_offset */
6, /* plt_got_insn_size */
PLT_ENTRY_SIZE, /* plt_plt_insn_end */
6, /* plt_lazy_offset */
elf_x86_64_eh_frame_plt, /* eh_frame_plt */
sizeof (elf_x86_64_eh_frame_plt), /* eh_frame_plt_size */
};
#define elf_backend_arch_data &elf_x86_64_arch_bed
/* x86-64 ELF linker hash entry. */
struct elf_x86_64_link_hash_entry
{
struct elf_link_hash_entry elf;
/* Track dynamic relocs copied for this symbol. */
struct elf_dyn_relocs *dyn_relocs;
#define GOT_UNKNOWN 0
#define GOT_NORMAL 1
#define GOT_TLS_GD 2
#define GOT_TLS_IE 3
#define GOT_TLS_GDESC 4
#define GOT_TLS_GD_BOTH_P(type) \
((type) == (GOT_TLS_GD | GOT_TLS_GDESC))
#define GOT_TLS_GD_P(type) \
((type) == GOT_TLS_GD || GOT_TLS_GD_BOTH_P (type))
#define GOT_TLS_GDESC_P(type) \
((type) == GOT_TLS_GDESC || GOT_TLS_GD_BOTH_P (type))
#define GOT_TLS_GD_ANY_P(type) \
(GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type))
unsigned char tls_type;
/* Offset of the GOTPLT entry reserved for the TLS descriptor,
starting at the end of the jump table. */
bfd_vma tlsdesc_got;
};
#define elf_x86_64_hash_entry(ent) \
((struct elf_x86_64_link_hash_entry *)(ent))
struct elf_x86_64_obj_tdata
{
struct elf_obj_tdata root;
/* tls_type for each local got entry. */
char *local_got_tls_type;
/* GOTPLT entries for TLS descriptors. */
bfd_vma *local_tlsdesc_gotent;
};
#define elf_x86_64_tdata(abfd) \
((struct elf_x86_64_obj_tdata *) (abfd)->tdata.any)
#define elf_x86_64_local_got_tls_type(abfd) \
(elf_x86_64_tdata (abfd)->local_got_tls_type)
#define elf_x86_64_local_tlsdesc_gotent(abfd) \
(elf_x86_64_tdata (abfd)->local_tlsdesc_gotent)
#define is_x86_64_elf(bfd) \
(bfd_get_flavour (bfd) == bfd_target_elf_flavour \
&& elf_tdata (bfd) != NULL \
&& elf_object_id (bfd) == X86_64_ELF_DATA)
static bfd_boolean
elf_x86_64_mkobject (bfd *abfd)
{
return bfd_elf_allocate_object (abfd, sizeof (struct elf_x86_64_obj_tdata),
X86_64_ELF_DATA);
}
/* x86-64 ELF linker hash table. */
struct elf_x86_64_link_hash_table
{
struct elf_link_hash_table elf;
/* Short-cuts to get to dynamic linker sections. */
asection *sdynbss;
asection *srelbss;
asection *plt_eh_frame;
union
{
bfd_signed_vma refcount;
bfd_vma offset;
} tls_ld_got;
/* The amount of space used by the jump slots in the GOT. */
bfd_vma sgotplt_jump_table_size;
/* Small local sym cache. */
struct sym_cache sym_cache;
bfd_vma (*r_info) (bfd_vma, bfd_vma);
bfd_vma (*r_sym) (bfd_vma);
unsigned int pointer_r_type;
const char *dynamic_interpreter;
int dynamic_interpreter_size;
/* _TLS_MODULE_BASE_ symbol. */
struct bfd_link_hash_entry *tls_module_base;
/* Used by local STT_GNU_IFUNC symbols. */
htab_t loc_hash_table;
void * loc_hash_memory;
/* The offset into splt of the PLT entry for the TLS descriptor
resolver. Special values are 0, if not necessary (or not found
to be necessary yet), and -1 if needed but not determined
yet. */
bfd_vma tlsdesc_plt;
/* The offset into sgot of the GOT entry used by the PLT entry
above. */
bfd_vma tlsdesc_got;
/* The index of the next R_X86_64_JUMP_SLOT entry in .rela.plt. */
bfd_vma next_jump_slot_index;
/* The index of the next R_X86_64_IRELATIVE entry in .rela.plt. */
bfd_vma next_irelative_index;
};
/* Get the x86-64 ELF linker hash table from a link_info structure. */
#define elf_x86_64_hash_table(p) \
(elf_hash_table_id ((struct elf_link_hash_table *) ((p)->hash)) \
== X86_64_ELF_DATA ? ((struct elf_x86_64_link_hash_table *) ((p)->hash)) : NULL)
#define elf_x86_64_compute_jump_table_size(htab) \
((htab)->elf.srelplt->reloc_count * GOT_ENTRY_SIZE)
/* Create an entry in an x86-64 ELF linker hash table. */
static struct bfd_hash_entry *
elf_x86_64_link_hash_newfunc (struct bfd_hash_entry *entry,
struct bfd_hash_table *table,
const char *string)
{
/* Allocate the structure if it has not already been allocated by a
subclass. */
if (entry == NULL)
{
entry = (struct bfd_hash_entry *)
bfd_hash_allocate (table,
sizeof (struct elf_x86_64_link_hash_entry));
if (entry == NULL)
return entry;
}
/* Call the allocation method of the superclass. */
entry = _bfd_elf_link_hash_newfunc (entry, table, string);
if (entry != NULL)
{
struct elf_x86_64_link_hash_entry *eh;
eh = (struct elf_x86_64_link_hash_entry *) entry;
eh->dyn_relocs = NULL;
eh->tls_type = GOT_UNKNOWN;
eh->tlsdesc_got = (bfd_vma) -1;
}
return entry;
}
/* Compute a hash of a local hash entry. We use elf_link_hash_entry
for local symbol so that we can handle local STT_GNU_IFUNC symbols
as global symbol. We reuse indx and dynstr_index for local symbol
hash since they aren't used by global symbols in this backend. */
static hashval_t
elf_x86_64_local_htab_hash (const void *ptr)
{
struct elf_link_hash_entry *h
= (struct elf_link_hash_entry *) ptr;
return ELF_LOCAL_SYMBOL_HASH (h->indx, h->dynstr_index);
}
/* Compare local hash entries. */
static int
elf_x86_64_local_htab_eq (const void *ptr1, const void *ptr2)
{
struct elf_link_hash_entry *h1
= (struct elf_link_hash_entry *) ptr1;
struct elf_link_hash_entry *h2
= (struct elf_link_hash_entry *) ptr2;
return h1->indx == h2->indx && h1->dynstr_index == h2->dynstr_index;
}
/* Find and/or create a hash entry for local symbol. */
static struct elf_link_hash_entry *
elf_x86_64_get_local_sym_hash (struct elf_x86_64_link_hash_table *htab,
bfd *abfd, const Elf_Internal_Rela *rel,
bfd_boolean create)
{
struct elf_x86_64_link_hash_entry e, *ret;
asection *sec = abfd->sections;
hashval_t h = ELF_LOCAL_SYMBOL_HASH (sec->id,
htab->r_sym (rel->r_info));
void **slot;
e.elf.indx = sec->id;
e.elf.dynstr_index = htab->r_sym (rel->r_info);
slot = htab_find_slot_with_hash (htab->loc_hash_table, &e, h,
create ? INSERT : NO_INSERT);
if (!slot)
return NULL;
if (*slot)
{
ret = (struct elf_x86_64_link_hash_entry *) *slot;
return &ret->elf;
}
ret = (struct elf_x86_64_link_hash_entry *)
objalloc_alloc ((struct objalloc *) htab->loc_hash_memory,
sizeof (struct elf_x86_64_link_hash_entry));
if (ret)
{
memset (ret, 0, sizeof (*ret));
ret->elf.indx = sec->id;
ret->elf.dynstr_index = htab->r_sym (rel->r_info);
ret->elf.dynindx = -1;
*slot = ret;
}
return &ret->elf;
}
/* Create an X86-64 ELF linker hash table. */
static struct bfd_link_hash_table *
elf_x86_64_link_hash_table_create (bfd *abfd)
{
struct elf_x86_64_link_hash_table *ret;
bfd_size_type amt = sizeof (struct elf_x86_64_link_hash_table);
ret = (struct elf_x86_64_link_hash_table *) bfd_malloc (amt);
if (ret == NULL)
return NULL;
if (!_bfd_elf_link_hash_table_init (&ret->elf, abfd,
elf_x86_64_link_hash_newfunc,
sizeof (struct elf_x86_64_link_hash_entry),
X86_64_ELF_DATA))
{
free (ret);
return NULL;
}
ret->sdynbss = NULL;
ret->srelbss = NULL;
ret->plt_eh_frame = NULL;
ret->sym_cache.abfd = NULL;
ret->tlsdesc_plt = 0;
ret->tlsdesc_got = 0;
ret->tls_ld_got.refcount = 0;
ret->sgotplt_jump_table_size = 0;
ret->tls_module_base = NULL;
ret->next_jump_slot_index = 0;
ret->next_irelative_index = 0;
if (ABI_64_P (abfd))
{
ret->r_info = elf64_r_info;
ret->r_sym = elf64_r_sym;
ret->pointer_r_type = R_X86_64_64;
ret->dynamic_interpreter = ELF64_DYNAMIC_INTERPRETER;
ret->dynamic_interpreter_size = sizeof ELF64_DYNAMIC_INTERPRETER;
}
else
{
ret->r_info = elf32_r_info;
ret->r_sym = elf32_r_sym;
ret->pointer_r_type = R_X86_64_32;
ret->dynamic_interpreter = ELF32_DYNAMIC_INTERPRETER;
ret->dynamic_interpreter_size = sizeof ELF32_DYNAMIC_INTERPRETER;
}
ret->loc_hash_table = htab_try_create (1024,
elf_x86_64_local_htab_hash,
elf_x86_64_local_htab_eq,
NULL);
ret->loc_hash_memory = objalloc_create ();
if (!ret->loc_hash_table || !ret->loc_hash_memory)
{
free (ret);
return NULL;
}
return &ret->elf.root;
}
/* Destroy an X86-64 ELF linker hash table. */
static void
elf_x86_64_link_hash_table_free (struct bfd_link_hash_table *hash)
{
struct elf_x86_64_link_hash_table *htab
= (struct elf_x86_64_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_generic_link_hash_table_free (hash);
}
/* Create .plt, .rela.plt, .got, .got.plt, .rela.got, .dynbss, and
.rela.bss sections in DYNOBJ, and set up shortcuts to them in our
hash table. */
static bfd_boolean
elf_x86_64_create_dynamic_sections (bfd *dynobj,
struct bfd_link_info *info)
{
struct elf_x86_64_link_hash_table *htab;
if (!_bfd_elf_create_dynamic_sections (dynobj, info))
return FALSE;
htab = elf_x86_64_hash_table (info);
if (htab == NULL)
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))
abort ();
if (!info->no_ld_generated_unwind_info
&& htab->plt_eh_frame == NULL
&& htab->elf.splt != NULL)
{
flagword flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY
| SEC_HAS_CONTENTS | SEC_IN_MEMORY
| SEC_LINKER_CREATED);
htab->plt_eh_frame
= bfd_make_section_anyway_with_flags (dynobj, ".eh_frame", flags);
if (htab->plt_eh_frame == NULL
|| !bfd_set_section_alignment (dynobj, htab->plt_eh_frame, 3))
return FALSE;
}
return TRUE;
}
/* Copy the extra info we tack onto an elf_link_hash_entry. */
static void
elf_x86_64_copy_indirect_symbol (struct bfd_link_info *info,
struct elf_link_hash_entry *dir,
struct elf_link_hash_entry *ind)
{
struct elf_x86_64_link_hash_entry *edir, *eind;
edir = (struct elf_x86_64_link_hash_entry *) dir;
eind = (struct elf_x86_64_link_hash_entry *) ind;
if (eind->dyn_relocs != NULL)
{
if (edir->dyn_relocs != NULL)
{
struct elf_dyn_relocs **pp;
struct elf_dyn_relocs *p;
/* Add reloc counts against the indirect sym to the direct sym
list. Merge any entries against the same section. */
for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
{
struct elf_dyn_relocs *q;
for (q = edir->dyn_relocs; q != NULL; q = q->next)
if (q->sec == p->sec)
{
q->pc_count += p->pc_count;
q->count += p->count;
*pp = p->next;
break;
}
if (q == NULL)
pp = &p->next;
}
*pp = edir->dyn_relocs;
}
edir->dyn_relocs = eind->dyn_relocs;
eind->dyn_relocs = NULL;
}
if (ind->root.type == bfd_link_hash_indirect
&& dir->got.refcount <= 0)
{
edir->tls_type = eind->tls_type;
eind->tls_type = GOT_UNKNOWN;
}
if (ELIMINATE_COPY_RELOCS
&& ind->root.type != bfd_link_hash_indirect
&& dir->dynamic_adjusted)
{
/* If called to transfer flags for a weakdef during processing
of elf_adjust_dynamic_symbol, don't copy non_got_ref.
We clear it ourselves for ELIMINATE_COPY_RELOCS. */
dir->ref_dynamic |= ind->ref_dynamic;
dir->ref_regular |= ind->ref_regular;
dir->ref_regular_nonweak |= ind->ref_regular_nonweak;
dir->needs_plt |= ind->needs_plt;
dir->pointer_equality_needed |= ind->pointer_equality_needed;
}
else
_bfd_elf_link_hash_copy_indirect (info, dir, ind);
}
static bfd_boolean
elf64_x86_64_elf_object_p (bfd *abfd)
{
/* Set the right machine number for an x86-64 elf64 file. */
bfd_default_set_arch_mach (abfd, bfd_arch_i386, bfd_mach_x86_64);
return TRUE;
}
static bfd_boolean
elf32_x86_64_elf_object_p (bfd *abfd)
{
/* Set the right machine number for an x86-64 elf32 file. */
bfd_default_set_arch_mach (abfd, bfd_arch_i386, bfd_mach_x64_32);
return TRUE;
}
/* Return TRUE if the TLS access code sequence support transition
from R_TYPE. */
static bfd_boolean
elf_x86_64_check_tls_transition (bfd *abfd,
struct bfd_link_info *info,
asection *sec,
bfd_byte *contents,
Elf_Internal_Shdr *symtab_hdr,
struct elf_link_hash_entry **sym_hashes,
unsigned int r_type,
const Elf_Internal_Rela *rel,
const Elf_Internal_Rela *relend)
{
unsigned int val;
unsigned long r_symndx;
struct elf_link_hash_entry *h;
bfd_vma offset;
struct elf_x86_64_link_hash_table *htab;
/* Get the section contents. */
if (contents == NULL)
{
if (elf_section_data (sec)->this_hdr.contents != NULL)
contents = elf_section_data (sec)->this_hdr.contents;
else
{
/* FIXME: How to better handle error condition? */
if (!bfd_malloc_and_get_section (abfd, sec, &contents))
return FALSE;
/* Cache the section contents for elf_link_input_bfd. */
elf_section_data (sec)->this_hdr.contents = contents;
}
}
htab = elf_x86_64_hash_table (info);
offset = rel->r_offset;
switch (r_type)
{
case R_X86_64_TLSGD:
case R_X86_64_TLSLD:
if ((rel + 1) >= relend)
return FALSE;
if (r_type == R_X86_64_TLSGD)
{
/* Check transition from GD access model. For 64bit, only
.byte 0x66; leaq foo@tlsgd(%rip), %rdi
.word 0x6666; rex64; call __tls_get_addr
can transit to different access model. For 32bit, only
leaq foo@tlsgd(%rip), %rdi
.word 0x6666; rex64; call __tls_get_addr
can transit to different access model. */
static const unsigned char call[] = { 0x66, 0x66, 0x48, 0xe8 };
static const unsigned char leaq[] = { 0x66, 0x48, 0x8d, 0x3d };
if ((offset + 12) > sec->size
|| memcmp (contents + offset + 4, call, 4) != 0)
return FALSE;
if (ABI_64_P (abfd))
{
if (offset < 4
|| memcmp (contents + offset - 4, leaq, 4) != 0)
return FALSE;
}
else
{
if (offset < 3
|| memcmp (contents + offset - 3, leaq + 1, 3) != 0)
return FALSE;
}
}
else
{
/* Check transition from LD access model. Only
leaq foo@tlsld(%rip), %rdi;
call __tls_get_addr
can transit to different access model. */
static const unsigned char lea[] = { 0x48, 0x8d, 0x3d };
if (offset < 3 || (offset + 9) > sec->size)
return FALSE;
if (memcmp (contents + offset - 3, lea, 3) != 0
|| 0xe8 != *(contents + offset + 4))
return FALSE;
}
r_symndx = htab->r_sym (rel[1].r_info);
if (r_symndx < symtab_hdr->sh_info)
return FALSE;
h = sym_hashes[r_symndx - symtab_hdr->sh_info];
/* Use strncmp to check __tls_get_addr since __tls_get_addr
may be versioned. */
return (h != NULL
&& h->root.root.string != NULL
&& (ELF32_R_TYPE (rel[1].r_info) == R_X86_64_PC32
|| ELF32_R_TYPE (rel[1].r_info) == R_X86_64_PLT32)
&& (strncmp (h->root.root.string,
"__tls_get_addr", 14) == 0));
case R_X86_64_GOTTPOFF:
/* Check transition from IE access model:
mov foo@gottpoff(%rip), %reg
add foo@gottpoff(%rip), %reg
*/
/* Check REX prefix first. */
if (offset >= 3 && (offset + 4) <= sec->size)
{
val = bfd_get_8 (abfd, contents + offset - 3);
if (val != 0x48 && val != 0x4c)
{
/* X32 may have 0x44 REX prefix or no REX prefix. */
if (ABI_64_P (abfd))
return FALSE;
}
}
else
{
/* X32 may not have any REX prefix. */
if (ABI_64_P (abfd))
return FALSE;
if (offset < 2 || (offset + 3) > sec->size)
return FALSE;
}
val = bfd_get_8 (abfd, contents + offset - 2);
if (val != 0x8b && val != 0x03)
return FALSE;
val = bfd_get_8 (abfd, contents + offset - 1);
return (val & 0xc7) == 5;
case R_X86_64_GOTPC32_TLSDESC:
/* Check transition from GDesc access model:
leaq x@tlsdesc(%rip), %rax
Make sure it's a leaq adding rip to a 32-bit offset
into any register, although it's probably almost always
going to be rax. */
if (offset < 3 || (offset + 4) > sec->size)
return FALSE;
val = bfd_get_8 (abfd, contents + offset - 3);
if ((val & 0xfb) != 0x48)
return FALSE;
if (bfd_get_8 (abfd, contents + offset - 2) != 0x8d)
return FALSE;
val = bfd_get_8 (abfd, contents + offset - 1);
return (val & 0xc7) == 0x05;
case R_X86_64_TLSDESC_CALL:
/* Check transition from GDesc access model:
call *x@tlsdesc(%rax)
*/
if (offset + 2 <= sec->size)
{
/* Make sure that it's a call *x@tlsdesc(%rax). */
static const unsigned char call[] = { 0xff, 0x10 };
return memcmp (contents + offset, call, 2) == 0;
}
return FALSE;
default:
abort ();
}
}
/* Return TRUE if the TLS access transition is OK or no transition
will be performed. Update R_TYPE if there is a transition. */
static bfd_boolean
elf_x86_64_tls_transition (struct bfd_link_info *info, bfd *abfd,
asection *sec, bfd_byte *contents,
Elf_Internal_Shdr *symtab_hdr,
struct elf_link_hash_entry **sym_hashes,
unsigned int *r_type, int tls_type,
const Elf_Internal_Rela *rel,
const Elf_Internal_Rela *relend,
struct elf_link_hash_entry *h,
unsigned long r_symndx)
{
unsigned int from_type = *r_type;
unsigned int to_type = from_type;
bfd_boolean check = TRUE;
/* Skip TLS transition for functions. */
if (h != NULL
&& (h->type == STT_FUNC
|| h->type == STT_GNU_IFUNC))
return TRUE;
switch (from_type)
{
case R_X86_64_TLSGD:
case R_X86_64_GOTPC32_TLSDESC:
case R_X86_64_TLSDESC_CALL:
case R_X86_64_GOTTPOFF:
if (info->executable)
{
if (h == NULL)
to_type = R_X86_64_TPOFF32;
else
to_type = R_X86_64_GOTTPOFF;
}
/* When we are called from elf_x86_64_relocate_section,
CONTENTS isn't NULL and there may be additional transitions
based on TLS_TYPE. */
if (contents != NULL)
{
unsigned int new_to_type = to_type;
if (info->executable
&& h != NULL
&& h->dynindx == -1
&& tls_type == GOT_TLS_IE)
new_to_type = R_X86_64_TPOFF32;
if (to_type == R_X86_64_TLSGD
|| to_type == R_X86_64_GOTPC32_TLSDESC
|| to_type == R_X86_64_TLSDESC_CALL)
{
if (tls_type == GOT_TLS_IE)
new_to_type = R_X86_64_GOTTPOFF;
}
/* We checked the transition before when we were called from
elf_x86_64_check_relocs. We only want to check the new
transition which hasn't been checked before. */
check = new_to_type != to_type && from_type == to_type;
to_type = new_to_type;
}
break;
case R_X86_64_TLSLD:
if (info->executable)
to_type = R_X86_64_TPOFF32;
break;
default:
return TRUE;
}
/* Return TRUE if there is no transition. */
if (from_type == to_type)
return TRUE;
/* Check if the transition can be performed. */
if (check
&& ! elf_x86_64_check_tls_transition (abfd, info, sec, contents,
symtab_hdr, sym_hashes,
from_type, rel, relend))
{
reloc_howto_type *from, *to;
const char *name;
from = elf_x86_64_rtype_to_howto (abfd, from_type);
to = elf_x86_64_rtype_to_howto (abfd, to_type);
if (h)
name = h->root.root.string;
else
{
struct elf_x86_64_link_hash_table *htab;
htab = elf_x86_64_hash_table (info);
if (htab == NULL)
name = "*unknown*";
else
{
Elf_Internal_Sym *isym;
isym = bfd_sym_from_r_symndx (&htab->sym_cache,
abfd, r_symndx);
name = bfd_elf_sym_name (abfd, symtab_hdr, isym, NULL);
}
}
(*_bfd_error_handler)
(_("%B: TLS transition from %s to %s against `%s' at 0x%lx "
"in section `%A' failed"),
abfd, sec, from->name, to->name, name,
(unsigned long) rel->r_offset);
bfd_set_error (bfd_error_bad_value);
return FALSE;
}
*r_type = to_type;
return TRUE;
}
/* 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. */
static bfd_boolean
elf_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info,
asection *sec,
const Elf_Internal_Rela *relocs)
{
struct elf_x86_64_link_hash_table *htab;
Elf_Internal_Shdr *symtab_hdr;
struct elf_link_hash_entry **sym_hashes;
const Elf_Internal_Rela *rel;
const Elf_Internal_Rela *rel_end;
asection *sreloc;
if (info->relocatable)
return TRUE;
BFD_ASSERT (is_x86_64_elf (abfd));
htab = elf_x86_64_hash_table (info);
if (htab == NULL)
return FALSE;
symtab_hdr = &elf_symtab_hdr (abfd);
sym_hashes = elf_sym_hashes (abfd);
sreloc = NULL;
rel_end = relocs + sec->reloc_count;
for (rel = relocs; rel < rel_end; rel++)
{
unsigned int r_type;
unsigned long r_symndx;
struct elf_link_hash_entry *h;
Elf_Internal_Sym *isym;
const char *name;
r_symndx = htab->r_sym (rel->r_info);
r_type = ELF32_R_TYPE (rel->r_info);
if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr))
{
(*_bfd_error_handler) (_("%B: bad symbol index: %d"),
abfd, r_symndx);
return FALSE;
}
if (r_symndx < symtab_hdr->sh_info)
{
/* A local symbol. */
isym = bfd_sym_from_r_symndx (&htab->sym_cache,
abfd, r_symndx);
if (isym == NULL)
return FALSE;
/* Check relocation against local STT_GNU_IFUNC symbol. */
if (ELF_ST_TYPE (isym->st_info) == STT_GNU_IFUNC)
{
h = elf_x86_64_get_local_sym_hash (htab, abfd, rel,
TRUE);
if (h == NULL)
return FALSE;
/* Fake a STT_GNU_IFUNC symbol. */
h->type = STT_GNU_IFUNC;
h->def_regular = 1;
h->ref_regular = 1;
h->forced_local = 1;
h->root.type = bfd_link_hash_defined;
}
else
h = NULL;
}
else
{
isym = NULL;
h = sym_hashes[r_symndx - symtab_hdr->sh_info];
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;
}
/* Check invalid x32 relocations. */
if (!ABI_64_P (abfd))
switch (r_type)
{
default:
break;
case R_X86_64_DTPOFF64:
case R_X86_64_TPOFF64:
case R_X86_64_PC64:
case R_X86_64_GOTOFF64:
case R_X86_64_GOT64:
case R_X86_64_GOTPCREL64:
case R_X86_64_GOTPC64:
case R_X86_64_GOTPLT64:
case R_X86_64_PLTOFF64:
{
if (h)
name = h->root.root.string;
else
name = bfd_elf_sym_name (abfd, symtab_hdr, isym,
NULL);
(*_bfd_error_handler)
(_("%B: relocation %s against symbol `%s' isn't "
"supported in x32 mode"), abfd,
x86_64_elf_howto_table[r_type].name, name);
bfd_set_error (bfd_error_bad_value);
return FALSE;
}
break;
}
if (h != NULL)
{
/* Create the ifunc sections for static executables. If we
never see an indirect function symbol nor we are building
a static executable, those sections will be empty and
won't appear in output. */
switch (r_type)
{
default:
break;
case R_X86_64_32S:
case R_X86_64_32:
case R_X86_64_64:
case R_X86_64_PC32:
case R_X86_64_PC64:
case R_X86_64_PLT32:
case R_X86_64_GOTPCREL:
case R_X86_64_GOTPCREL64:
if (htab->elf.dynobj == NULL)
htab->elf.dynobj = abfd;
if (!_bfd_elf_create_ifunc_sections (htab->elf.dynobj, info))
return FALSE;
break;
}
/* Since STT_GNU_IFUNC symbol must go through PLT, we handle
it here if it is defined in a non-shared object. */
if (h->type == STT_GNU_IFUNC
&& h->def_regular)
{
/* It is referenced by a non-shared object. */
h->ref_regular = 1;
h->needs_plt = 1;
/* STT_GNU_IFUNC symbol must go through PLT. */
h->plt.refcount += 1;
/* STT_GNU_IFUNC needs dynamic sections. */
if (htab->elf.dynobj == NULL)
htab->elf.dynobj = abfd;
switch (r_type)
{
default:
if (h->root.root.string)
name = h->root.root.string;
else
name = bfd_elf_sym_name (abfd, symtab_hdr, isym,
NULL);
(*_bfd_error_handler)
(_("%B: relocation %s against STT_GNU_IFUNC "
"symbol `%s' isn't handled by %s"), abfd,
x86_64_elf_howto_table[r_type].name,
name, __FUNCTION__);
bfd_set_error (bfd_error_bad_value);
return FALSE;
case R_X86_64_32:
if (ABI_64_P (abfd))
goto not_pointer;
case R_X86_64_64:
h->non_got_ref = 1;
h->pointer_equality_needed = 1;
if (info->shared)
{
/* We must copy these reloc types into the output
file. Create a reloc section in dynobj and
make room for this reloc. */
sreloc = _bfd_elf_create_ifunc_dyn_reloc
(abfd, info, sec, sreloc,
&((struct elf_x86_64_link_hash_entry *) h)->dyn_relocs);
if (sreloc == NULL)
return FALSE;
}
break;
case R_X86_64_32S:
case R_X86_64_PC32:
case R_X86_64_PC64:
not_pointer:
h->non_got_ref = 1;
if (r_type != R_X86_64_PC32
&& r_type != R_X86_64_PC64)
h->pointer_equality_needed = 1;
break;
case R_X86_64_PLT32:
break;
case R_X86_64_GOTPCREL:
case R_X86_64_GOTPCREL64:
h->got.refcount += 1;
if (htab->elf.sgot == NULL
&& !_bfd_elf_create_got_section (htab->elf.dynobj,
info))
return FALSE;
break;
}
continue;
}
}
if (! elf_x86_64_tls_transition (info, abfd, sec, NULL,
symtab_hdr, sym_hashes,
&r_type, GOT_UNKNOWN,
rel, rel_end, h, r_symndx))
return FALSE;
switch (r_type)
{
case R_X86_64_TLSLD:
htab->tls_ld_got.refcount += 1;
goto create_got;
case R_X86_64_TPOFF32:
if (!info->executable && ABI_64_P (abfd))
{
if (h)
name = h->root.root.string;
else
name = bfd_elf_sym_name (abfd, symtab_hdr, isym,
NULL);
(*_bfd_error_handler)
(_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
abfd,
x86_64_elf_howto_table[r_type].name, name);
bfd_set_error (bfd_error_bad_value);
return FALSE;
}
break;
case R_X86_64_GOTTPOFF:
if (!info->executable)
info->flags |= DF_STATIC_TLS;
/* Fall through */
case R_X86_64_GOT32:
case R_X86_64_GOTPCREL:
case R_X86_64_TLSGD:
case R_X86_64_GOT64:
case R_X86_64_GOTPCREL64:
case R_X86_64_GOTPLT64:
case R_X86_64_GOTPC32_TLSDESC:
case R_X86_64_TLSDESC_CALL:
/* This symbol requires a global offset table entry. */
{
int tls_type, old_tls_type;
switch (r_type)
{
default: tls_type = GOT_NORMAL; break;
case R_X86_64_TLSGD: tls_type = GOT_TLS_GD; break;
case R_X86_64_GOTTPOFF: tls_type = GOT_TLS_IE; break;
case R_X86_64_GOTPC32_TLSDESC:
case R_X86_64_TLSDESC_CALL:
tls_type = GOT_TLS_GDESC; break;
}
if (h != NULL)
{
if (r_type == R_X86_64_GOTPLT64)
{
/* This relocation indicates that we also need
a PLT entry, as this is a function. We don't need
a PLT entry for local symbols. */
h->needs_plt = 1;
h->plt.refcount += 1;
}
h->got.refcount += 1;
old_tls_type = elf_x86_64_hash_entry (h)->tls_type;
}
else
{
bfd_signed_vma *local_got_refcounts;
/* This is a global offset table entry for a local symbol. */
local_got_refcounts = elf_local_got_refcounts (abfd);
if (local_got_refcounts == NULL)
{
bfd_size_type size;
size = symtab_hdr->sh_info;
size *= sizeof (bfd_signed_vma)
+ sizeof (bfd_vma) + sizeof (char);
local_got_refcounts = ((bfd_signed_vma *)
bfd_zalloc (abfd, size));
if (local_got_refcounts == NULL)
return FALSE;
elf_local_got_refcounts (abfd) = local_got_refcounts;
elf_x86_64_local_tlsdesc_gotent (abfd)
= (bfd_vma *) (local_got_refcounts + symtab_hdr->sh_info);
elf_x86_64_local_got_tls_type (abfd)
= (char *) (local_got_refcounts + 2 * symtab_hdr->sh_info);
}
local_got_refcounts[r_symndx] += 1;
old_tls_type
= elf_x86_64_local_got_tls_type (abfd) [r_symndx];
}
/* If a TLS symbol is accessed using IE at least once,
there is no point to use dynamic model for it. */
if (old_tls_type != tls_type && old_tls_type != GOT_UNKNOWN
&& (! GOT_TLS_GD_ANY_P (old_tls_type)
|| tls_type != GOT_TLS_IE))
{
if (old_tls_type == GOT_TLS_IE && GOT_TLS_GD_ANY_P (tls_type))
tls_type = old_tls_type;
else if (GOT_TLS_GD_ANY_P (old_tls_type)
&& GOT_TLS_GD_ANY_P (tls_type))
tls_type |= old_tls_type;
else
{
if (h)
name = h->root.root.string;
else
name = bfd_elf_sym_name (abfd, symtab_hdr,
isym, NULL);
(*_bfd_error_handler)
(_("%B: '%s' accessed both as normal and thread local symbol"),
abfd, name);
return FALSE;
}
}
if (old_tls_type != tls_type)
{
if (h != NULL)
elf_x86_64_hash_entry (h)->tls_type = tls_type;
else
elf_x86_64_local_got_tls_type (abfd) [r_symndx] = tls_type;
}
}
/* Fall through */
case R_X86_64_GOTOFF64:
case R_X86_64_GOTPC32:
case R_X86_64_GOTPC64:
create_got:
if (htab->elf.sgot == NULL)
{
if (htab->elf.dynobj == NULL)
htab->elf.dynobj = abfd;
if (!_bfd_elf_create_got_section (htab->elf.dynobj,
info))
return FALSE;
}
break;
case R_X86_64_PLT32:
/* This symbol requires a procedure linkage table entry. We
actually build the entry in adjust_dynamic_symbol,
because this might be a case of linking PIC code which is
never referenced by a dynamic object, in which case we
don't need to generate a procedure linkage table entry
after all. */
/* If this is a local symbol, we resolve it directly without
creating a procedure linkage table entry. */
if (h == NULL)
continue;
h->needs_plt = 1;
h->plt.refcount += 1;
break;
case R_X86_64_PLTOFF64:
/* This tries to form the 'address' of a function relative
to GOT. For global symbols we need a PLT entry. */
if (h != NULL)
{
h->needs_plt = 1;
h->plt.refcount += 1;
}
goto create_got;
case R_X86_64_32:
if (!ABI_64_P (abfd))
goto pointer;
case R_X86_64_8:
case R_X86_64_16:
case R_X86_64_32S:
/* 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
&& (sec->flags & SEC_ALLOC) != 0
&& (sec->flags & SEC_READONLY) != 0)
{
if (h)
name = h->root.root.string;
else
name = bfd_elf_sym_name (abfd, symtab_hdr, isym, NULL);
(*_bfd_error_handler)
(_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
abfd, x86_64_elf_howto_table[r_type].name, name);
bfd_set_error (bfd_error_bad_value);
return FALSE;
}
/* Fall through. */
case R_X86_64_PC8:
case R_X86_64_PC16:
case R_X86_64_PC32:
case R_X86_64_PC64:
case R_X86_64_64:
pointer:
if (h != NULL && info->executable)
{
/* If this reloc is in a read-only section, we might
need a copy reloc. We can't check reliably at this
stage whether the section is read-only, as input
sections have not yet been mapped to output sections.
Tentatively set the flag for now, and correct in
adjust_dynamic_symbol. */
h->non_got_ref = 1;
/* 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_PC64)
h->pointer_equality_needed = 1;
}
/* If we are creating a shared library, and this is a reloc
against a global symbol, or a non PC relative reloc
against a local symbol, then we need to copy the reloc
into the shared library. However, if we are linking with
-Bsymbolic, we do not need to copy a reloc against a
global symbol which is defined in an object we are
including in the link (i.e., DEF_REGULAR is set). At
this point we have not seen all the input files, so it is
possible that DEF_REGULAR is not set now but will be set
later (it is never cleared). In case of a weak definition,
DEF_REGULAR may be cleared later by a strong definition in
a shared library. We account for that possibility below by
storing information in the relocs_copied field of the hash
table entry. A similar situation occurs when creating
shared libraries and symbol visibility changes render the
symbol local.
If on the other hand, we are creating an executable, we
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
&& (sec->flags & SEC_ALLOC) != 0
&& (! IS_X86_64_PCREL_TYPE (r_type)
|| (h != NULL
&& (! SYMBOLIC_BIND (info, h)
|| h->root.type == bfd_link_hash_defweak
|| !h->def_regular))))
|| (ELIMINATE_COPY_RELOCS
&& !info->shared
&& (sec->flags & SEC_ALLOC) != 0
&& h != NULL
&& (h->root.type == bfd_link_hash_defweak
|| !h->def_regular)))
{
struct elf_dyn_relocs *p;
struct elf_dyn_relocs **head;
/* We must copy these reloc types into the output file.
Create a reloc section in dynobj and make room for
this reloc. */
if (sreloc == NULL)
{
if (htab->elf.dynobj == NULL)
htab->elf.dynobj = abfd;
sreloc = _bfd_elf_make_dynamic_reloc_section
(sec, htab->elf.dynobj, ABI_64_P (abfd) ? 3 : 2,
abfd, /*rela?*/ TRUE);
if (sreloc == NULL)
return FALSE;
}
/* 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;
}
else
{
/* Track dynamic relocs needed for local syms too.
We really need local syms available to do this
easily. Oh well. */
asection *s;
void **vpp;
isym = bfd_sym_from_r_symndx (&htab->sym_cache,
abfd, r_symndx);
if (isym == NULL)
return FALSE;
s = bfd_section_from_elf_index (abfd, isym->st_shndx);
if (s == NULL)
s = sec;
/* Beware of type punned pointers vs strict aliasing
rules. */
vpp = &(elf_section_data (s)->local_dynrel);
head = (struct elf_dyn_relocs **)vpp;
}
p = *head;
if (p == NULL || p->sec != sec)
{
bfd_size_type amt = sizeof *p;
p = ((struct elf_dyn_relocs *)
bfd_alloc (htab->elf.dynobj, amt));
if (p == NULL)
return FALSE;
p->next = *head;
*head = p;
p->sec = sec;
p->count = 0;
p->pc_count = 0;
}
p->count += 1;
if (IS_X86_64_PCREL_TYPE (r_type))
p->pc_count += 1;
}
break;
/* This relocation describes the C++ object vtable hierarchy.
Reconstruct it for later use during GC. */
case R_X86_64_GNU_VTINHERIT:
if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
return FALSE;
break;
/* This relocation describes which C++ vtable entries are actually
used. Record for later use during GC. */
case R_X86_64_GNU_VTENTRY:
BFD_ASSERT (h != NULL);
if (h != NULL
&& !bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_addend))
return FALSE;
break;
default:
break;
}
}
return TRUE;
}
/* Return the section that should be marked against GC for a given
relocation. */
static asection *
elf_x86_64_gc_mark_hook (asection *sec,
struct bfd_link_info *info,
Elf_Internal_Rela *rel,
struct elf_link_hash_entry *h,
Elf_Internal_Sym *sym)
{
if (h != NULL)
switch (ELF32_R_TYPE (rel->r_info))
{
case R_X86_64_GNU_VTINHERIT:
case R_X86_64_GNU_VTENTRY:
return NULL;
}
return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
}
/* Update the got entry reference counts for the section being removed. */
static bfd_boolean
elf_x86_64_gc_sweep_hook (bfd *abfd, struct bfd_link_info *info,
asection *sec,
const Elf_Internal_Rela *relocs)
{
struct elf_x86_64_link_hash_table *htab;
Elf_Internal_Shdr *symtab_hdr;
struct elf_link_hash_entry **sym_hashes;
bfd_signed_vma *local_got_refcounts;
const Elf_Internal_Rela *rel, *relend;
if (info->relocatable)
return TRUE;
htab = elf_x86_64_hash_table (info);
if (htab == NULL)
return FALSE;
elf_section_data (sec)->local_dynrel = NULL;
symtab_hdr = &elf_symtab_hdr (abfd);
sym_hashes = elf_sym_hashes (abfd);
local_got_refcounts = elf_local_got_refcounts (abfd);
htab = elf_x86_64_hash_table (info);
relend = relocs + sec->reloc_count;
for (rel = relocs; rel < relend; rel++)
{
unsigned long r_symndx;
unsigned int r_type;
struct elf_link_hash_entry *h = NULL;
r_symndx = htab->r_sym (rel->r_info);
if (r_symndx >= symtab_hdr->sh_info)
{
h = sym_hashes[r_symndx - symtab_hdr->sh_info];
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;
}
else
{
/* A local symbol. */
Elf_Internal_Sym *isym;
isym = bfd_sym_from_r_symndx (&htab->sym_cache,
abfd, r_symndx);
/* Check relocation against local STT_GNU_IFUNC symbol. */
if (isym != NULL
&& ELF_ST_TYPE (isym->st_info) == STT_GNU_IFUNC)
{
h = elf_x86_64_get_local_sym_hash (htab, abfd, rel, FALSE);
if (h == NULL)
abort ();
}
}
if (h)
{
struct elf_x86_64_link_hash_entry *eh;
struct elf_dyn_relocs **pp;
struct elf_dyn_relocs *p;
eh = (struct elf_x86_64_link_hash_entry *) h;
for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
if (p->sec == sec)
{
/* Everything must go for SEC. */
*pp = p->next;
break;
}
}
r_type = ELF32_R_TYPE (rel->r_info);
if (! elf_x86_64_tls_transition (info, abfd, sec, NULL,
symtab_hdr, sym_hashes,
&r_type, GOT_UNKNOWN,
rel, relend, h, r_symndx))
return FALSE;
switch (r_type)
{
case R_X86_64_TLSLD:
if (htab->tls_ld_got.refcount > 0)
htab->tls_ld_got.refcount -= 1;
break;
case R_X86_64_TLSGD:
case R_X86_64_GOTPC32_TLSDESC:
case R_X86_64_TLSDESC_CALL:
case R_X86_64_GOTTPOFF:
case R_X86_64_GOT32:
case R_X86_64_GOTPCREL:
case R_X86_64_GOT64:
case R_X86_64_GOTPCREL64:
case R_X86_64_GOTPLT64:
if (h != NULL)
{
if (r_type == R_X86_64_GOTPLT64 && h->plt.refcount > 0)
h->plt.refcount -= 1;
if (h->got.refcount > 0)
h->got.refcount -= 1;
if (h->type == STT_GNU_IFUNC)
{
if (h->plt.refcount > 0)
h->plt.refcount -= 1;
}
}
else if (local_got_refcounts != NULL)
{
if (local_got_refcounts[r_symndx] > 0)
local_got_refcounts[r_symndx] -= 1;
}
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:
case R_X86_64_PC8:
case R_X86_64_PC16:
case R_X86_64_PC32:
case R_X86_64_PC64:
if (info->shared
&& (h == NULL || h->type != STT_GNU_IFUNC))
break;
/* Fall thru */
case R_X86_64_PLT32:
case R_X86_64_PLTOFF64:
if (h != NULL)
{
if (h->plt.refcount > 0)
h->plt.refcount -= 1;
}
break;
default:
break;
}
}
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
change the definition to something the rest of the link can
understand. */
static bfd_boolean
elf_x86_64_adjust_dynamic_symbol (struct bfd_link_info *info,
struct elf_link_hash_entry *h)
{
struct elf_x86_64_link_hash_table *htab;
asection *s;
/* STT_GNU_IFUNC symbol must go through PLT. */
if (h->type == STT_GNU_IFUNC)
{
if (h->plt.refcount <= 0)
{
h->plt.offset = (bfd_vma) -1;
h->needs_plt = 0;
}
return TRUE;
}
/* If this is a function, put it in the procedure linkage table. We
will fill in the contents of the procedure linkage table later,
when we know the address of the .got section. */
if (h->type == STT_FUNC
|| h->needs_plt)
{
if (h->plt.refcount <= 0
|| SYMBOL_CALLS_LOCAL (info, h)
|| (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
&& h->root.type == bfd_link_hash_undefweak))
{
/* This case can occur if we saw a PLT32 reloc in an input
file, but the symbol was never referred to by a dynamic
object, or if all references were garbage collected. In
such a case, we don't actually need to build a procedure
linkage table, and we can just do a PC32 reloc instead. */
h->plt.offset = (bfd_vma) -1;
h->needs_plt = 0;
}
return TRUE;
}
else
/* It's possible that we incorrectly decided a .plt reloc was
needed for an R_X86_64_PC32 reloc to a non-function sym in
check_relocs. We can't decide accurately between function and
non-function syms in check-relocs; Objects loaded later in
the link may change h->type. So fix it now. */
h->plt.offset = (bfd_vma) -1;
/* If this is a weak symbol, and there is a real definition, the
processor independent code will have arranged for us to see the
real definition first, and we can just use the same value. */
if (h->u.weakdef != NULL)
{
BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined
|| h->u.weakdef->root.type == bfd_link_hash_defweak);
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;
return TRUE;
}
/* This is a reference to a symbol defined by a dynamic object which
is not a function. */
/* If we are creating a shared library, we must presume that the
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)
return TRUE;
/* If there are no references to this symbol that do not use the
GOT, we don't need to generate a copy reloc. */
if (!h->non_got_ref)
return TRUE;
/* If -z nocopyreloc was given, we won't generate them either. */
if (info->nocopyreloc)
{
h->non_got_ref = 0;
return TRUE;
}
if (ELIMINATE_COPY_RELOCS)
{
struct elf_x86_64_link_hash_entry * eh;
struct elf_dyn_relocs *p;
eh = (struct elf_x86_64_link_hash_entry *) h;
for (p = eh->dyn_relocs; p != NULL; p = p->next)
{
s = p->sec->output_section;
if (s != NULL && (s->flags & SEC_READONLY) != 0)
break;
}
/* If we didn't find any dynamic relocs in read-only sections, then
we'll be keeping the dynamic relocs and avoiding the copy reloc. */
if (p == NULL)
{
h->non_got_ref = 0;
return TRUE;
}
}
/* We must allocate the symbol in our .dynbss section, which will
become part of the .bss section of the executable. There will be
an entry for this symbol in the .dynsym section. The dynamic
object will contain position independent code, so all references
from the dynamic object to this symbol will go through the global
offset table. The dynamic linker will use the .dynsym entry to
determine the address it must put in the global offset table, so
both the dynamic object and the regular object will refer to the
same memory location for the variable. */
htab = elf_x86_64_hash_table (info);
if (htab == NULL)
return FALSE;
/* We must generate a R_X86_64_COPY reloc to tell the dynamic linker
to copy the initial value out of the dynamic object and into the
runtime process image. */
if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
{
const struct elf_backend_data *bed;
bed = get_elf_backend_data (info->output_bfd);
htab->srelbss->size += bed->s->sizeof_rela;
h->needs_copy = 1;
}
s = htab->sdynbss;
return _bfd_elf_adjust_dynamic_copy (h, s);
}
/* Allocate space in .plt, .got and associated reloc sections for
dynamic relocs. */
static bfd_boolean
elf_x86_64_allocate_dynrelocs (struct elf_link_hash_entry *h, void * inf)
{
struct bfd_link_info *info;
struct elf_x86_64_link_hash_table *htab;
struct elf_x86_64_link_hash_entry *eh;
struct elf_dyn_relocs *p;
const struct elf_backend_data *bed;
unsigned int plt_entry_size;
if (h->root.type == bfd_link_hash_indirect)
return TRUE;
eh = (struct elf_x86_64_link_hash_entry *) h;
info = (struct bfd_link_info *) inf;
htab = elf_x86_64_hash_table (info);
if (htab == NULL)
return FALSE;
bed = get_elf_backend_data (info->output_bfd);
plt_entry_size = GET_PLT_ENTRY_SIZE (info->output_bfd);
/* Since STT_GNU_IFUNC symbol must go through PLT, we handle it
here if it is defined and referenced in a non-shared object. */
if (h->type == STT_GNU_IFUNC
&& h->def_regular)
return _bfd_elf_allocate_ifunc_dyn_relocs (info, h,
&eh->dyn_relocs,
plt_entry_size,
GOT_ENTRY_SIZE);
else if (htab->elf.dynamic_sections_created
&& h->plt.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)
{
if (! bfd_elf_link_record_dynamic_symbol (info, h))
return FALSE;
}
if (info->shared
|| WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h))
{
asection *s = htab->elf.splt;
/* 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 this symbol is not defined in a regular file, and we are
not generating a shared library, then set the symbol to this
location in the .plt. This is required to make function
pointers compare as equal between the normal executable and
the shared library. */
if (! info->shared
&& !h->def_regular)
{
h->root.u.def.section = s;
h->root.u.def.value = h->plt.offset;
}
/* Make room for this entry. */
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 += 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++;
}
else
{
h->plt.offset = (bfd_vma) -1;
h->needs_plt = 0;
}
}
else
{
h->plt.offset = (bfd_vma) -1;
h->needs_plt = 0;
}
eh->tlsdesc_got = (bfd_vma) -1;
/* 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
&& h->dynindx == -1
&& elf_x86_64_hash_entry (h)->tls_type == GOT_TLS_IE)
{
h->got.offset = (bfd_vma) -1;
}
else if (h->got.refcount > 0)
{
asection *s;
bfd_boolean dyn;
int tls_type = elf_x86_64_hash_entry (h)->tls_type;
/* Make sure this symbol is output as a dynamic symbol.
Undefined weak syms won't yet be marked as dynamic. */
if (h->dynindx == -1
&& !h->forced_local)
{
if (! bfd_elf_link_record_dynamic_symbol (info, h))
return FALSE;
}
if (GOT_TLS_GDESC_P (tls_type))
{
eh->tlsdesc_got = htab->elf.sgotplt->size
- elf_x86_64_compute_jump_table_size (htab);
htab->elf.sgotplt->size += 2 * GOT_ENTRY_SIZE;
h->got.offset = (bfd_vma) -2;
}
if (! GOT_TLS_GDESC_P (tls_type)
|| GOT_TLS_GD_P (tls_type))
{
s = htab->elf.sgot;
h->got.offset = s->size;
s->size += GOT_ENTRY_SIZE;
if (GOT_TLS_GD_P (tls_type))
s->size += GOT_ENTRY_SIZE;
}
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. */
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
|| h->root.type != bfd_link_hash_undefweak)
&& (info->shared
|| WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h)))
htab->elf.srelgot->size += bed->s->sizeof_rela;
if (GOT_TLS_GDESC_P (tls_type))
{
htab->elf.srelplt->size += bed->s->sizeof_rela;
htab->tlsdesc_plt = (bfd_vma) -1;
}
}
else
h->got.offset = (bfd_vma) -1;
if (eh->dyn_relocs == NULL)
return TRUE;
/* In the shared -Bsymbolic case, discard space allocated for
dynamic pc-relative relocs against symbols which turn out to be
defined in regular objects. For the normal shared case, discard
space for pc-relative relocs that have become local due to symbol
visibility changes. */
if (info->shared)
{
/* Relocs that use pc_count are those that appear on a call
insn, or certain REL relocs that can generated via assembly.
We want calls to protected symbols to resolve directly to the
function rather than going via the plt. If people want
function pointer comparisons to work as expected then they
should avoid writing weird assembly. */
if (SYMBOL_CALLS_LOCAL (info, h))
{
struct elf_dyn_relocs **pp;
for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
{
p->count -= p->pc_count;
p->pc_count = 0;
if (p->count == 0)
*pp = p->next;
else
pp = &p->next;
}
}
/* Also discard relocs on undefined weak syms with non-default
visibility. */
if (eh->dyn_relocs != NULL
&& h->root.type == bfd_link_hash_undefweak)
{
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;
}
}
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. */
if (!h->non_got_ref
&& ((h->def_dynamic
&& !h->def_regular)
|| (htab->elf.dynamic_sections_created
&& (h->root.type == bfd_link_hash_undefweak
|| h->root.type == bfd_link_hash_undefined))))
{
/* Make sure this symbol is output as a dynamic symbol.
Undefined weak syms won't yet be marked as dynamic. */
if (h->dynindx == -1
&& ! h->forced_local
&& ! bfd_elf_link_record_dynamic_symbol (info, h))
return FALSE;
/* If that succeeded, we know we'll be keeping all the
relocs. */
if (h->dynindx != -1)
goto keep;
}
eh->dyn_relocs = NULL;
keep: ;
}
/* Finally, allocate space. */
for (p = eh->dyn_relocs; p != NULL; p = p->next)
{
asection * sreloc;
sreloc = elf_section_data (p->sec)->sreloc;
BFD_ASSERT (sreloc != NULL);
sreloc->size += p->count * bed->s->sizeof_rela;
}
return TRUE;
}
/* Allocate space in .plt, .got and associated reloc sections for
local dynamic relocs. */
static bfd_boolean
elf_x86_64_allocate_local_dynrelocs (void **slot, void *inf)
{
struct elf_link_hash_entry *h
= (struct elf_link_hash_entry *) *slot;
if (h->type != STT_GNU_IFUNC
|| !h->def_regular
|| !h->ref_regular
|| !h->forced_local
|| h->root.type != bfd_link_hash_defined)
abort ();
return elf_x86_64_allocate_dynrelocs (h, inf);
}
/* Find any dynamic relocs that apply to read-only sections. */
static bfd_boolean
elf_x86_64_readonly_dynrelocs (struct elf_link_hash_entry *h,
void * inf)
{
struct elf_x86_64_link_hash_entry *eh;
struct elf_dyn_relocs *p;
/* Skip local IFUNC symbols. */
if (h->forced_local && h->type == STT_GNU_IFUNC)
return TRUE;
eh = (struct elf_x86_64_link_hash_entry *) h;
for (p = eh->dyn_relocs; p != NULL; p = p->next)
{
asection *s = p->sec->output_section;
if (s != NULL && (s->flags & SEC_READONLY) != 0)
{
struct bfd_link_info *info = (struct bfd_link_info *) inf;
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"),
p->sec->owner, h->root.root.string,
p->sec);
/* Not an error, just cut short the traversal. */
return FALSE;
}
}
return TRUE;
}
/* Set the sizes of the dynamic sections. */
static bfd_boolean
elf_x86_64_size_dynamic_sections (bfd *output_bfd,
struct bfd_link_info *info)
{
struct elf_x86_64_link_hash_table *htab;
bfd *dynobj;
asection *s;
bfd_boolean relocs;
bfd *ibfd;
const struct elf_backend_data *bed;
htab = elf_x86_64_hash_table (info);
if (htab == NULL)
return FALSE;
bed = get_elf_backend_data (output_bfd);
dynobj = htab->elf.dynobj;
if (dynobj == NULL)
abort ();
if (htab->elf.dynamic_sections_created)
{
/* Set the contents of the .interp section to the interpreter. */
if (info->executable)
{
s = bfd_get_linker_section (dynobj, ".interp");
if (s == NULL)
abort ();
s->size = htab->dynamic_interpreter_size;
s->contents = (unsigned char *) htab->dynamic_interpreter;
}
}
/* Set up .got offsets for local syms, and space for local dynamic
relocs. */
for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
{
bfd_signed_vma *local_got;
bfd_signed_vma *end_local_got;
char *local_tls_type;
bfd_vma *local_tlsdesc_gotent;
bfd_size_type locsymcount;
Elf_Internal_Shdr *symtab_hdr;
asection *srel;
if (! is_x86_64_elf (ibfd))
continue;
for (s = ibfd->sections; s != NULL; s = s->next)
{
struct elf_dyn_relocs *p;
for (p = (struct elf_dyn_relocs *)
(elf_section_data (s)->local_dynrel);
p != NULL;
p = p->next)
{
if (!bfd_is_abs_section (p->sec)
&& bfd_is_abs_section (p->sec->output_section))
{
/* Input section has been discarded, either because
it is a copy of a linkonce section or due to
linker script /DISCARD/, so we'll be discarding
the relocs too. */
}
else if (p->count != 0)
{
srel = elf_section_data (p->sec)->sreloc;
srel->size += p->count * bed->s->sizeof_rela;
if ((p->sec->output_section->flags & SEC_READONLY) != 0
&& (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"),
p->sec->owner, p->sec);
}
}
}
}
local_got = elf_local_got_refcounts (ibfd);
if (!local_got)
continue;
symtab_hdr = &elf_symtab_hdr (ibfd);
locsymcount = symtab_hdr->sh_info;
end_local_got = local_got + locsymcount;
local_tls_type = elf_x86_64_local_got_tls_type (ibfd);
local_tlsdesc_gotent = elf_x86_64_local_tlsdesc_gotent (ibfd);
s = htab->elf.sgot;
srel = htab->elf.srelgot;
for (; local_got < end_local_got;
++local_got, ++local_tls_type, ++local_tlsdesc_gotent)
{
*local_tlsdesc_gotent = (bfd_vma) -1;
if (*local_got > 0)
{
if (GOT_TLS_GDESC_P (*local_tls_type))
{
*local_tlsdesc_gotent = htab->elf.sgotplt->size
- elf_x86_64_compute_jump_table_size (htab);
htab->elf.sgotplt->size += 2 * GOT_ENTRY_SIZE;
*local_got = (bfd_vma) -2;
}
if (! GOT_TLS_GDESC_P (*local_tls_type)
|| GOT_TLS_GD_P (*local_tls_type))
{
*local_got = s->size;
s->size += GOT_ENTRY_SIZE;
if (GOT_TLS_GD_P (*local_tls_type))
s->size += GOT_ENTRY_SIZE;
}
if (info->shared
|| GOT_TLS_GD_ANY_P (*local_tls_type)
|| *local_tls_type == GOT_TLS_IE)
{
if (GOT_TLS_GDESC_P (*local_tls_type))
{
htab->elf.srelplt->size
+= bed->s->sizeof_rela;
htab->tlsdesc_plt = (bfd_vma) -1;
}
if (! GOT_TLS_GDESC_P (*local_tls_type)
|| GOT_TLS_GD_P (*local_tls_type))
srel->size += bed->s->sizeof_rela;
}
}
else
*local_got = (bfd_vma) -1;
}
}
if (htab->tls_ld_got.refcount > 0)
{
/* Allocate 2 got entries and 1 dynamic reloc for R_X86_64_TLSLD
relocs. */
htab->tls_ld_got.offset = htab->elf.sgot->size;
htab->elf.sgot->size += 2 * GOT_ENTRY_SIZE;
htab->elf.srelgot->size += bed->s->sizeof_rela;
}
else
htab->tls_ld_got.offset = -1;
/* Alloca