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elf.c
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13633 lines (11867 loc) · 383 KB
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/* ELF executable support for BFD.
Copyright (C) 1993-2023 Free Software Foundation, Inc.
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. */
/*
SECTION
ELF backends
BFD support for ELF formats is being worked on.
Currently, the best supported back ends are for sparc and i386
(running svr4 or Solaris 2).
Documentation of the internals of the support code still needs
to be written. The code is changing quickly enough that we
haven't bothered yet. */
/* For sparc64-cross-sparc32. */
#define _SYSCALL32
#include "sysdep.h"
#include <limits.h>
#include "bfd.h"
#include "bfdlink.h"
#include "libbfd.h"
#define ARCH_SIZE 0
#include "elf-bfd.h"
#include "libiberty.h"
#include "safe-ctype.h"
#include "elf-linux-core.h"
#ifdef CORE_HEADER
#include CORE_HEADER
#endif
static int elf_sort_sections (const void *, const void *);
static bool assign_file_positions_except_relocs (bfd *, struct bfd_link_info *);
static bool swap_out_syms (bfd *, struct elf_strtab_hash **, int,
struct bfd_link_info *);
static bool elf_parse_notes (bfd *abfd, char *buf, size_t size,
file_ptr offset, size_t align);
/* Swap version information in and out. The version information is
currently size independent. If that ever changes, this code will
need to move into elfcode.h. */
/* Swap in a Verdef structure. */
void
_bfd_elf_swap_verdef_in (bfd *abfd,
const Elf_External_Verdef *src,
Elf_Internal_Verdef *dst)
{
dst->vd_version = H_GET_16 (abfd, src->vd_version);
dst->vd_flags = H_GET_16 (abfd, src->vd_flags);
dst->vd_ndx = H_GET_16 (abfd, src->vd_ndx);
dst->vd_cnt = H_GET_16 (abfd, src->vd_cnt);
dst->vd_hash = H_GET_32 (abfd, src->vd_hash);
dst->vd_aux = H_GET_32 (abfd, src->vd_aux);
dst->vd_next = H_GET_32 (abfd, src->vd_next);
}
/* Swap out a Verdef structure. */
void
_bfd_elf_swap_verdef_out (bfd *abfd,
const Elf_Internal_Verdef *src,
Elf_External_Verdef *dst)
{
H_PUT_16 (abfd, src->vd_version, dst->vd_version);
H_PUT_16 (abfd, src->vd_flags, dst->vd_flags);
H_PUT_16 (abfd, src->vd_ndx, dst->vd_ndx);
H_PUT_16 (abfd, src->vd_cnt, dst->vd_cnt);
H_PUT_32 (abfd, src->vd_hash, dst->vd_hash);
H_PUT_32 (abfd, src->vd_aux, dst->vd_aux);
H_PUT_32 (abfd, src->vd_next, dst->vd_next);
}
/* Swap in a Verdaux structure. */
void
_bfd_elf_swap_verdaux_in (bfd *abfd,
const Elf_External_Verdaux *src,
Elf_Internal_Verdaux *dst)
{
dst->vda_name = H_GET_32 (abfd, src->vda_name);
dst->vda_next = H_GET_32 (abfd, src->vda_next);
}
/* Swap out a Verdaux structure. */
void
_bfd_elf_swap_verdaux_out (bfd *abfd,
const Elf_Internal_Verdaux *src,
Elf_External_Verdaux *dst)
{
H_PUT_32 (abfd, src->vda_name, dst->vda_name);
H_PUT_32 (abfd, src->vda_next, dst->vda_next);
}
/* Swap in a Verneed structure. */
void
_bfd_elf_swap_verneed_in (bfd *abfd,
const Elf_External_Verneed *src,
Elf_Internal_Verneed *dst)
{
dst->vn_version = H_GET_16 (abfd, src->vn_version);
dst->vn_cnt = H_GET_16 (abfd, src->vn_cnt);
dst->vn_file = H_GET_32 (abfd, src->vn_file);
dst->vn_aux = H_GET_32 (abfd, src->vn_aux);
dst->vn_next = H_GET_32 (abfd, src->vn_next);
}
/* Swap out a Verneed structure. */
void
_bfd_elf_swap_verneed_out (bfd *abfd,
const Elf_Internal_Verneed *src,
Elf_External_Verneed *dst)
{
H_PUT_16 (abfd, src->vn_version, dst->vn_version);
H_PUT_16 (abfd, src->vn_cnt, dst->vn_cnt);
H_PUT_32 (abfd, src->vn_file, dst->vn_file);
H_PUT_32 (abfd, src->vn_aux, dst->vn_aux);
H_PUT_32 (abfd, src->vn_next, dst->vn_next);
}
/* Swap in a Vernaux structure. */
void
_bfd_elf_swap_vernaux_in (bfd *abfd,
const Elf_External_Vernaux *src,
Elf_Internal_Vernaux *dst)
{
dst->vna_hash = H_GET_32 (abfd, src->vna_hash);
dst->vna_flags = H_GET_16 (abfd, src->vna_flags);
dst->vna_other = H_GET_16 (abfd, src->vna_other);
dst->vna_name = H_GET_32 (abfd, src->vna_name);
dst->vna_next = H_GET_32 (abfd, src->vna_next);
}
/* Swap out a Vernaux structure. */
void
_bfd_elf_swap_vernaux_out (bfd *abfd,
const Elf_Internal_Vernaux *src,
Elf_External_Vernaux *dst)
{
H_PUT_32 (abfd, src->vna_hash, dst->vna_hash);
H_PUT_16 (abfd, src->vna_flags, dst->vna_flags);
H_PUT_16 (abfd, src->vna_other, dst->vna_other);
H_PUT_32 (abfd, src->vna_name, dst->vna_name);
H_PUT_32 (abfd, src->vna_next, dst->vna_next);
}
/* Swap in a Versym structure. */
void
_bfd_elf_swap_versym_in (bfd *abfd,
const Elf_External_Versym *src,
Elf_Internal_Versym *dst)
{
dst->vs_vers = H_GET_16 (abfd, src->vs_vers);
}
/* Swap out a Versym structure. */
void
_bfd_elf_swap_versym_out (bfd *abfd,
const Elf_Internal_Versym *src,
Elf_External_Versym *dst)
{
H_PUT_16 (abfd, src->vs_vers, dst->vs_vers);
}
/* Standard ELF hash function. Do not change this function; you will
cause invalid hash tables to be generated. */
unsigned long long
bfd_elf_hash (const char *namearg)
{
uint32_t h = 0;
for (const unsigned char *name = (const unsigned char *) namearg;
*name; name++)
{
h = (h << 4) + *name;
h ^= (h >> 24) & 0xf0;
}
return h & 0x0fffffff;
}
/* DT_GNU_HASH hash function. Do not change this function; you will
cause invalid hash tables to be generated. */
unsigned long long
bfd_elf_gnu_hash (const char *namearg)
{
uint32_t h = 5381;
for (const unsigned char *name = (const unsigned char *) namearg;
*name; name++)
h = (h << 5) + h + *name;
return h;
}
/* Create a tdata field OBJECT_SIZE bytes in length, zeroed out and with
the object_id field of an elf_obj_tdata field set to OBJECT_ID. */
bool
bfd_elf_allocate_object (bfd *abfd,
size_t object_size,
enum elf_target_id object_id)
{
BFD_ASSERT (object_size >= sizeof (struct elf_obj_tdata));
abfd->tdata.any = bfd_zalloc (abfd, object_size);
if (abfd->tdata.any == NULL)
return false;
elf_object_id (abfd) = object_id;
if (abfd->direction != read_direction)
{
struct output_elf_obj_tdata *o = bfd_zalloc (abfd, sizeof *o);
if (o == NULL)
return false;
elf_tdata (abfd)->o = o;
elf_program_header_size (abfd) = (bfd_size_type) -1;
}
return true;
}
bool
bfd_elf_make_object (bfd *abfd)
{
const struct elf_backend_data *bed = get_elf_backend_data (abfd);
return bfd_elf_allocate_object (abfd, sizeof (struct elf_obj_tdata),
bed->target_id);
}
bool
bfd_elf_mkcorefile (bfd *abfd)
{
/* I think this can be done just like an object file. */
if (!abfd->xvec->_bfd_set_format[(int) bfd_object] (abfd))
return false;
elf_tdata (abfd)->core = bfd_zalloc (abfd, sizeof (*elf_tdata (abfd)->core));
return elf_tdata (abfd)->core != NULL;
}
char *
bfd_elf_get_str_section (bfd *abfd, unsigned int shindex)
{
Elf_Internal_Shdr **i_shdrp;
bfd_byte *shstrtab = NULL;
file_ptr offset;
bfd_size_type shstrtabsize;
i_shdrp = elf_elfsections (abfd);
if (i_shdrp == 0
|| shindex >= elf_numsections (abfd)
|| i_shdrp[shindex] == 0)
return NULL;
shstrtab = i_shdrp[shindex]->contents;
if (shstrtab == NULL)
{
/* No cached one, attempt to read, and cache what we read. */
offset = i_shdrp[shindex]->sh_offset;
shstrtabsize = i_shdrp[shindex]->sh_size;
/* Allocate and clear an extra byte at the end, to prevent crashes
in case the string table is not terminated. */
if (shstrtabsize + 1 <= 1
|| bfd_seek (abfd, offset, SEEK_SET) != 0
|| (shstrtab = _bfd_alloc_and_read (abfd, shstrtabsize + 1,
shstrtabsize)) == NULL)
{
/* Once we've failed to read it, make sure we don't keep
trying. Otherwise, we'll keep allocating space for
the string table over and over. */
i_shdrp[shindex]->sh_size = 0;
}
else
shstrtab[shstrtabsize] = '\0';
i_shdrp[shindex]->contents = shstrtab;
}
return (char *) shstrtab;
}
char *
bfd_elf_string_from_elf_section (bfd *abfd,
unsigned int shindex,
unsigned int strindex)
{
Elf_Internal_Shdr *hdr;
if (strindex == 0)
return "";
if (elf_elfsections (abfd) == NULL || shindex >= elf_numsections (abfd))
return NULL;
hdr = elf_elfsections (abfd)[shindex];
if (hdr->contents == NULL)
{
if (hdr->sh_type != SHT_STRTAB && hdr->sh_type < SHT_LOOS)
{
/* PR 17512: file: f057ec89. */
/* xgettext:c-format */
_bfd_error_handler (_("%pB: attempt to load strings from"
" a non-string section (number %d)"),
abfd, shindex);
return NULL;
}
if (bfd_elf_get_str_section (abfd, shindex) == NULL)
return NULL;
}
else
{
/* PR 24273: The string section's contents may have already
been loaded elsewhere, eg because a corrupt file has the
string section index in the ELF header pointing at a group
section. So be paranoid, and test that the last byte of
the section is zero. */
if (hdr->sh_size == 0 || hdr->contents[hdr->sh_size - 1] != 0)
return NULL;
}
if (strindex >= hdr->sh_size)
{
unsigned int shstrndx = elf_elfheader(abfd)->e_shstrndx;
_bfd_error_handler
/* xgettext:c-format */
(_("%pB: invalid string offset %u >= %" PRIu64 " for section `%s'"),
abfd, strindex, (uint64_t) hdr->sh_size,
(shindex == shstrndx && strindex == hdr->sh_name
? ".shstrtab"
: bfd_elf_string_from_elf_section (abfd, shstrndx, hdr->sh_name)));
return NULL;
}
return ((char *) hdr->contents) + strindex;
}
/* Read and convert symbols to internal format.
SYMCOUNT specifies the number of symbols to read, starting from
symbol SYMOFFSET. If any of INTSYM_BUF, EXTSYM_BUF or EXTSHNDX_BUF
are non-NULL, they are used to store the internal symbols, external
symbols, and symbol section index extensions, respectively.
Returns a pointer to the internal symbol buffer (malloced if necessary)
or NULL if there were no symbols or some kind of problem. */
Elf_Internal_Sym *
bfd_elf_get_elf_syms (bfd *ibfd,
Elf_Internal_Shdr *symtab_hdr,
size_t symcount,
size_t symoffset,
Elf_Internal_Sym *intsym_buf,
void *extsym_buf,
Elf_External_Sym_Shndx *extshndx_buf)
{
Elf_Internal_Shdr *shndx_hdr;
void *alloc_ext;
const bfd_byte *esym;
Elf_External_Sym_Shndx *alloc_extshndx;
Elf_External_Sym_Shndx *shndx;
Elf_Internal_Sym *alloc_intsym;
Elf_Internal_Sym *isym;
Elf_Internal_Sym *isymend;
const struct elf_backend_data *bed;
size_t extsym_size;
size_t amt;
file_ptr pos;
if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
abort ();
if (symcount == 0)
return intsym_buf;
/* Normal syms might have section extension entries. */
shndx_hdr = NULL;
if (elf_symtab_shndx_list (ibfd) != NULL)
{
elf_section_list * entry;
Elf_Internal_Shdr **sections = elf_elfsections (ibfd);
/* Find an index section that is linked to this symtab section. */
for (entry = elf_symtab_shndx_list (ibfd); entry != NULL; entry = entry->next)
{
/* PR 20063. */
if (entry->hdr.sh_link >= elf_numsections (ibfd))
continue;
if (sections[entry->hdr.sh_link] == symtab_hdr)
{
shndx_hdr = & entry->hdr;
break;
};
}
if (shndx_hdr == NULL)
{
if (symtab_hdr == &elf_symtab_hdr (ibfd))
/* Not really accurate, but this was how the old code used
to work. */
shndx_hdr = &elf_symtab_shndx_list (ibfd)->hdr;
/* Otherwise we do nothing. The assumption is that
the index table will not be needed. */
}
}
/* Read the symbols. */
alloc_ext = NULL;
alloc_extshndx = NULL;
alloc_intsym = NULL;
bed = get_elf_backend_data (ibfd);
extsym_size = bed->s->sizeof_sym;
if (_bfd_mul_overflow (symcount, extsym_size, &amt))
{
bfd_set_error (bfd_error_file_too_big);
intsym_buf = NULL;
goto out;
}
pos = symtab_hdr->sh_offset + symoffset * extsym_size;
if (extsym_buf == NULL)
{
alloc_ext = bfd_malloc (amt);
extsym_buf = alloc_ext;
}
if (extsym_buf == NULL
|| bfd_seek (ibfd, pos, SEEK_SET) != 0
|| bfd_bread (extsym_buf, amt, ibfd) != amt)
{
intsym_buf = NULL;
goto out;
}
if (shndx_hdr == NULL || shndx_hdr->sh_size == 0)
extshndx_buf = NULL;
else
{
if (_bfd_mul_overflow (symcount, sizeof (Elf_External_Sym_Shndx), &amt))
{
bfd_set_error (bfd_error_file_too_big);
intsym_buf = NULL;
goto out;
}
pos = shndx_hdr->sh_offset + symoffset * sizeof (Elf_External_Sym_Shndx);
if (extshndx_buf == NULL)
{
alloc_extshndx = (Elf_External_Sym_Shndx *) bfd_malloc (amt);
extshndx_buf = alloc_extshndx;
}
if (extshndx_buf == NULL
|| bfd_seek (ibfd, pos, SEEK_SET) != 0
|| bfd_bread (extshndx_buf, amt, ibfd) != amt)
{
intsym_buf = NULL;
goto out;
}
}
if (intsym_buf == NULL)
{
if (_bfd_mul_overflow (symcount, sizeof (Elf_Internal_Sym), &amt))
{
bfd_set_error (bfd_error_file_too_big);
goto out;
}
alloc_intsym = (Elf_Internal_Sym *) bfd_malloc (amt);
intsym_buf = alloc_intsym;
if (intsym_buf == NULL)
goto out;
}
/* Convert the symbols to internal form. */
isymend = intsym_buf + symcount;
for (esym = (const bfd_byte *) extsym_buf, isym = intsym_buf,
shndx = extshndx_buf;
isym < isymend;
esym += extsym_size, isym++, shndx = shndx != NULL ? shndx + 1 : NULL)
if (!(*bed->s->swap_symbol_in) (ibfd, esym, shndx, isym))
{
symoffset += (esym - (bfd_byte *) extsym_buf) / extsym_size;
/* xgettext:c-format */
_bfd_error_handler (_("%pB symbol number %lu references"
" nonexistent SHT_SYMTAB_SHNDX section"),
ibfd, (unsigned long long) symoffset);
free (alloc_intsym);
intsym_buf = NULL;
goto out;
}
out:
free (alloc_ext);
free (alloc_extshndx);
return intsym_buf;
}
/* Look up a symbol name. */
const char *
bfd_elf_sym_name (bfd *abfd,
Elf_Internal_Shdr *symtab_hdr,
Elf_Internal_Sym *isym,
asection *sym_sec)
{
const char *name;
unsigned int iname = isym->st_name;
unsigned int shindex = symtab_hdr->sh_link;
if (iname == 0 && ELF_ST_TYPE (isym->st_info) == STT_SECTION
/* Check for a bogus st_shndx to avoid crashing. */
&& isym->st_shndx < elf_numsections (abfd))
{
iname = elf_elfsections (abfd)[isym->st_shndx]->sh_name;
shindex = elf_elfheader (abfd)->e_shstrndx;
}
name = bfd_elf_string_from_elf_section (abfd, shindex, iname);
if (name == NULL)
name = "(null)";
else if (sym_sec && *name == '\0')
name = bfd_section_name (sym_sec);
return name;
}
/* Elf_Internal_Shdr->contents is an array of these for SHT_GROUP
sections. The first element is the flags, the rest are section
pointers. */
typedef union elf_internal_group {
Elf_Internal_Shdr *shdr;
unsigned int flags;
} Elf_Internal_Group;
/* Return the name of the group signature symbol. Why isn't the
signature just a string? */
static const char *
group_signature (bfd *abfd, Elf_Internal_Shdr *ghdr)
{
Elf_Internal_Shdr *hdr;
unsigned char esym[sizeof (Elf64_External_Sym)];
Elf_External_Sym_Shndx eshndx;
Elf_Internal_Sym isym;
/* First we need to ensure the symbol table is available. Make sure
that it is a symbol table section. */
if (ghdr->sh_link >= elf_numsections (abfd))
return NULL;
hdr = elf_elfsections (abfd) [ghdr->sh_link];
if (hdr->sh_type != SHT_SYMTAB
|| ! bfd_section_from_shdr (abfd, ghdr->sh_link))
return NULL;
/* Go read the symbol. */
hdr = &elf_tdata (abfd)->symtab_hdr;
if (bfd_elf_get_elf_syms (abfd, hdr, 1, ghdr->sh_info,
&isym, esym, &eshndx) == NULL)
return NULL;
return bfd_elf_sym_name (abfd, hdr, &isym, NULL);
}
/* Set next_in_group list pointer, and group name for NEWSECT. */
static bool
setup_group (bfd *abfd, Elf_Internal_Shdr *hdr, asection *newsect)
{
unsigned int num_group = elf_tdata (abfd)->num_group;
/* If num_group is zero, read in all SHT_GROUP sections. The count
is set to -1 if there are no SHT_GROUP sections. */
if (num_group == 0)
{
unsigned int i, shnum;
/* First count the number of groups. If we have a SHT_GROUP
section with just a flag word (ie. sh_size is 4), ignore it. */
shnum = elf_numsections (abfd);
num_group = 0;
#define IS_VALID_GROUP_SECTION_HEADER(shdr, minsize) \
( (shdr)->sh_type == SHT_GROUP \
&& (shdr)->sh_size >= minsize \
&& (shdr)->sh_entsize == GRP_ENTRY_SIZE \
&& ((shdr)->sh_size % GRP_ENTRY_SIZE) == 0)
for (i = 0; i < shnum; i++)
{
Elf_Internal_Shdr *shdr = elf_elfsections (abfd)[i];
if (IS_VALID_GROUP_SECTION_HEADER (shdr, 2 * GRP_ENTRY_SIZE))
num_group += 1;
}
if (num_group == 0)
{
num_group = (unsigned) -1;
elf_tdata (abfd)->num_group = num_group;
elf_tdata (abfd)->group_sect_ptr = NULL;
}
else
{
/* We keep a list of elf section headers for group sections,
so we can find them quickly. */
size_t amt;
elf_tdata (abfd)->num_group = num_group;
amt = num_group * sizeof (Elf_Internal_Shdr *);
elf_tdata (abfd)->group_sect_ptr
= (Elf_Internal_Shdr **) bfd_zalloc (abfd, amt);
if (elf_tdata (abfd)->group_sect_ptr == NULL)
return false;
num_group = 0;
for (i = 0; i < shnum; i++)
{
Elf_Internal_Shdr *shdr = elf_elfsections (abfd)[i];
if (IS_VALID_GROUP_SECTION_HEADER (shdr, 2 * GRP_ENTRY_SIZE))
{
unsigned char *src;
Elf_Internal_Group *dest;
/* Make sure the group section has a BFD section
attached to it. */
if (!bfd_section_from_shdr (abfd, i))
return false;
/* Add to list of sections. */
elf_tdata (abfd)->group_sect_ptr[num_group] = shdr;
num_group += 1;
/* Read the raw contents. */
BFD_ASSERT (sizeof (*dest) >= 4 && sizeof (*dest) % 4 == 0);
shdr->contents = NULL;
if (_bfd_mul_overflow (shdr->sh_size,
sizeof (*dest) / 4, &amt)
|| bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0
|| !(shdr->contents
= _bfd_alloc_and_read (abfd, amt, shdr->sh_size)))
{
_bfd_error_handler
/* xgettext:c-format */
(_("%pB: invalid size field in group section"
" header: %#" PRIx64 ""),
abfd, (uint64_t) shdr->sh_size);
bfd_set_error (bfd_error_bad_value);
-- num_group;
continue;
}
/* Translate raw contents, a flag word followed by an
array of elf section indices all in target byte order,
to the flag word followed by an array of elf section
pointers. */
src = shdr->contents + shdr->sh_size;
dest = (Elf_Internal_Group *) (shdr->contents + amt);
while (1)
{
unsigned int idx;
src -= 4;
--dest;
idx = H_GET_32 (abfd, src);
if (src == shdr->contents)
{
dest->shdr = NULL;
dest->flags = idx;
if (shdr->bfd_section != NULL && (idx & GRP_COMDAT))
shdr->bfd_section->flags
|= SEC_LINK_ONCE | SEC_LINK_DUPLICATES_DISCARD;
break;
}
if (idx < shnum)
{
dest->shdr = elf_elfsections (abfd)[idx];
/* PR binutils/23199: All sections in a
section group should be marked with
SHF_GROUP. But some tools generate
broken objects without SHF_GROUP. Fix
them up here. */
dest->shdr->sh_flags |= SHF_GROUP;
}
if (idx >= shnum
|| dest->shdr->sh_type == SHT_GROUP)
{
_bfd_error_handler
(_("%pB: invalid entry in SHT_GROUP section [%u]"),
abfd, i);
dest->shdr = NULL;
}
}
}
}
/* PR 17510: Corrupt binaries might contain invalid groups. */
if (num_group != (unsigned) elf_tdata (abfd)->num_group)
{
elf_tdata (abfd)->num_group = num_group;
/* If all groups are invalid then fail. */
if (num_group == 0)
{
elf_tdata (abfd)->group_sect_ptr = NULL;
elf_tdata (abfd)->num_group = num_group = -1;
_bfd_error_handler
(_("%pB: no valid group sections found"), abfd);
bfd_set_error (bfd_error_bad_value);
}
}
}
}
if (num_group != (unsigned) -1)
{
unsigned int search_offset = elf_tdata (abfd)->group_search_offset;
unsigned int j;
for (j = 0; j < num_group; j++)
{
/* Begin search from previous found group. */
unsigned i = (j + search_offset) % num_group;
Elf_Internal_Shdr *shdr = elf_tdata (abfd)->group_sect_ptr[i];
Elf_Internal_Group *idx;
bfd_size_type n_elt;
if (shdr == NULL)
continue;
idx = (Elf_Internal_Group *) shdr->contents;
if (idx == NULL || shdr->sh_size < 4)
{
/* See PR 21957 for a reproducer. */
/* xgettext:c-format */
_bfd_error_handler (_("%pB: group section '%pA' has no contents"),
abfd, shdr->bfd_section);
elf_tdata (abfd)->group_sect_ptr[i] = NULL;
bfd_set_error (bfd_error_bad_value);
return false;
}
n_elt = shdr->sh_size / 4;
/* Look through this group's sections to see if current
section is a member. */
while (--n_elt != 0)
if ((++idx)->shdr == hdr)
{
asection *s = NULL;
/* We are a member of this group. Go looking through
other members to see if any others are linked via
next_in_group. */
idx = (Elf_Internal_Group *) shdr->contents;
n_elt = shdr->sh_size / 4;
while (--n_elt != 0)
if ((++idx)->shdr != NULL
&& (s = idx->shdr->bfd_section) != NULL
&& elf_next_in_group (s) != NULL)
break;
if (n_elt != 0)
{
/* Snarf the group name from other member, and
insert current section in circular list. */
elf_group_name (newsect) = elf_group_name (s);
elf_next_in_group (newsect) = elf_next_in_group (s);
elf_next_in_group (s) = newsect;
}
else
{
const char *gname;
gname = group_signature (abfd, shdr);
if (gname == NULL)
return false;
elf_group_name (newsect) = gname;
/* Start a circular list with one element. */
elf_next_in_group (newsect) = newsect;
}
/* If the group section has been created, point to the
new member. */
if (shdr->bfd_section != NULL)
elf_next_in_group (shdr->bfd_section) = newsect;
elf_tdata (abfd)->group_search_offset = i;
j = num_group - 1;
break;
}
}
}
if (elf_group_name (newsect) == NULL)
{
/* xgettext:c-format */
_bfd_error_handler (_("%pB: no group info for section '%pA'"),
abfd, newsect);
/* PR 29532: Return true here, even though the group info has not been
read. Separate debug info files can have empty group sections, but
we do not want this to prevent them from being loaded as otherwise
GDB will not be able to use them. */
return true;
}
return true;
}
bool
_bfd_elf_setup_sections (bfd *abfd)
{
unsigned int i;
unsigned int num_group = elf_tdata (abfd)->num_group;
bool result = true;
asection *s;
/* Process SHF_LINK_ORDER. */
for (s = abfd->sections; s != NULL; s = s->next)
{
Elf_Internal_Shdr *this_hdr = &elf_section_data (s)->this_hdr;
if ((this_hdr->sh_flags & SHF_LINK_ORDER) != 0)
{
unsigned int elfsec = this_hdr->sh_link;
/* An sh_link value of 0 is now allowed. It indicates that linked
to section has already been discarded, but that the current
section has been retained for some other reason. This linking
section is still a candidate for later garbage collection
however. */
if (elfsec == 0)
{
elf_linked_to_section (s) = NULL;
}
else
{
asection *linksec = NULL;
if (elfsec < elf_numsections (abfd))
{
this_hdr = elf_elfsections (abfd)[elfsec];
linksec = this_hdr->bfd_section;
}
/* PR 1991, 2008:
Some strip/objcopy may leave an incorrect value in
sh_link. We don't want to proceed. */
if (linksec == NULL)
{
_bfd_error_handler
/* xgettext:c-format */
(_("%pB: sh_link [%d] in section `%pA' is incorrect"),
s->owner, elfsec, s);
result = false;
}
elf_linked_to_section (s) = linksec;
}
}
else if (this_hdr->sh_type == SHT_GROUP
&& elf_next_in_group (s) == NULL)
{
_bfd_error_handler
/* xgettext:c-format */
(_("%pB: SHT_GROUP section [index %d] has no SHF_GROUP sections"),
abfd, elf_section_data (s)->this_idx);
result = false;
}
}
/* Process section groups. */
if (num_group == (unsigned) -1)
return result;
for (i = 0; i < num_group; i++)
{
Elf_Internal_Shdr *shdr = elf_tdata (abfd)->group_sect_ptr[i];
Elf_Internal_Group *idx;
unsigned int n_elt;
/* PR binutils/18758: Beware of corrupt binaries with invalid
group data. */
if (shdr == NULL || shdr->bfd_section == NULL || shdr->contents == NULL)
{
_bfd_error_handler
/* xgettext:c-format */
(_("%pB: section group entry number %u is corrupt"),
abfd, i);
result = false;
continue;
}
idx = (Elf_Internal_Group *) shdr->contents;
n_elt = shdr->sh_size / 4;
while (--n_elt != 0)
{
++ idx;
if (idx->shdr == NULL)
continue;
else if (idx->shdr->bfd_section)
elf_sec_group (idx->shdr->bfd_section) = shdr->bfd_section;
else if (idx->shdr->sh_type != SHT_RELA
&& idx->shdr->sh_type != SHT_REL)
{
/* There are some unknown sections in the group. */
_bfd_error_handler
/* xgettext:c-format */
(_("%pB: unknown type [%#x] section `%s' in group [%pA]"),
abfd,
idx->shdr->sh_type,
bfd_elf_string_from_elf_section (abfd,
(elf_elfheader (abfd)
->e_shstrndx),
idx->shdr->sh_name),
shdr->bfd_section);
result = false;
}
}
}
return result;
}
bool
bfd_elf_is_group_section (bfd *abfd ATTRIBUTE_UNUSED, const asection *sec)
{
return elf_next_in_group (sec) != NULL;
}
const char *
bfd_elf_group_name (bfd *abfd ATTRIBUTE_UNUSED, const asection *sec)
{
if (elf_sec_group (sec) != NULL)
return elf_group_name (sec);
return NULL;
}
/* This a copy of lto_section defined in GCC (lto-streamer.h). */
struct lto_section
{
int16_t major_version;
int16_t minor_version;
unsigned char slim_object;
/* Flags is a private field that is not defined publicly. */
uint16_t flags;
};
/* Make a BFD section from an ELF section. We store a pointer to the
BFD section in the bfd_section field of the header. */
bool
_bfd_elf_make_section_from_shdr (bfd *abfd,
Elf_Internal_Shdr *hdr,
const char *name,
int shindex)
{
asection *newsect;
flagword flags;
const struct elf_backend_data *bed;
unsigned int opb = bfd_octets_per_byte (abfd, NULL);
if (hdr->bfd_section != NULL)
return true;
newsect = bfd_make_section_anyway (abfd, name);
if (newsect == NULL)
return false;
hdr->bfd_section = newsect;
elf_section_data (newsect)->this_hdr = *hdr;
elf_section_data (newsect)->this_idx = shindex;
/* Always use the real type/flags. */
elf_section_type (newsect) = hdr->sh_type;