2005-02-06 H.J. Lu <hongjiu.lu@intel.com>

* elf32-i386.c (elf_i386_relocate_section): Disallow R_386_GOTOFF
	against protected function when building shared library.

	PR 584
	* elf64-x86-64.c (is_32bit_relative_branch): New.
	(elf64_x86_64_relocate_section): Alllow R_X86_64_PC32 on a
	protected function symbol when building shared library for
	32bit relative branch instruction.
This commit is contained in:
H.J. Lu 2005-02-06 18:11:30 +00:00
parent 5b90c7b5eb
commit 90f487dfe0
3 changed files with 64 additions and 6 deletions

View file

@ -1,3 +1,14 @@
2005-02-06 H.J. Lu <hongjiu.lu@intel.com>
* elf32-i386.c (elf_i386_relocate_section): Disallow R_386_GOTOFF
against protected function when building shared library.
PR 584
* elf64-x86-64.c (is_32bit_relative_branch): New.
(elf64_x86_64_relocate_section): Alllow R_X86_64_PC32 on a
protected function symbol when building shared library for
32bit relative branch instruction.
2005-02-06 Alan Modra <amodra@bigpond.net.au> 2005-02-06 Alan Modra <amodra@bigpond.net.au>
* elf64-ppc.c (add_symbol_adjust): Don't create fake descriptor * elf64-ppc.c (add_symbol_adjust): Don't create fake descriptor

View file

@ -2274,6 +2274,22 @@ elf_i386_relocate_section (bfd *output_bfd,
/* Relocation is relative to the start of the global offset /* Relocation is relative to the start of the global offset
table. */ table. */
/* Check to make sure it isn't a protected function symbol
for shared library since it may not be local when used
as function address. */
if (info->shared
&& h
&& h->def_regular
&& h->type == STT_FUNC
&& ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
{
(*_bfd_error_handler)
(_("%B: relocation R_386_GOTOFF against protected function `%s' can not be used when making a shared object"),
input_bfd, h->root.root.string);
bfd_set_error (bfd_error_bad_value);
return FALSE;
}
/* Note that sgot is not involved in this /* Note that sgot is not involved in this
calculation. We always want the start of .got.plt. If we calculation. We always want the start of .got.plt. If we
defined _GLOBAL_OFFSET_TABLE_ in a different way, as is defined _GLOBAL_OFFSET_TABLE_ in a different way, as is

View file

@ -1745,6 +1745,24 @@ tpoff (struct bfd_link_info *info, bfd_vma address)
return address - htab->tls_size - htab->tls_sec->vma; return address - htab->tls_size - htab->tls_sec->vma;
} }
/* Is the instruction before OFFSET in CONTENTS a 32bit relative
branch? */
static bfd_boolean
is_32bit_relative_branch (bfd_byte *contents, bfd_vma offset)
{
/* Opcode Instruction
0xe8 call
0xe9 jump
0x0f 0x8x conditional jump */
return ((offset > 0
&& (contents [offset - 1] == 0xe8
|| contents [offset - 1] == 0xe9))
|| (offset > 1
&& contents [offset - 2] == 0x0f
&& (contents [offset - 1] & 0xf0) == 0x80));
}
/* Relocate an x86_64 ELF section. */ /* Relocate an x86_64 ELF section. */
static bfd_boolean static bfd_boolean
@ -1950,13 +1968,26 @@ elf64_x86_64_relocate_section (bfd *output_bfd, struct bfd_link_info *info,
if (info->shared if (info->shared
&& !SYMBOL_REFERENCES_LOCAL (info, h) && !SYMBOL_REFERENCES_LOCAL (info, h)
&& (input_section->flags & SEC_ALLOC) != 0 && (input_section->flags & SEC_ALLOC) != 0
&& (input_section->flags & SEC_READONLY) != 0) && (input_section->flags & SEC_READONLY) != 0
&& (!h->def_regular
|| r_type != R_X86_64_PC32
|| h->type != STT_FUNC
|| ELF_ST_VISIBILITY (h->other) != STV_PROTECTED
|| !is_32bit_relative_branch (contents,
rel->r_offset)))
{ {
if (h->def_regular
&& r_type == R_X86_64_PC32
&& h->type == STT_FUNC
&& ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
(*_bfd_error_handler)
(_("%B: relocation R_X86_64_PC32 against protected function `%s' can not be used when making a shared object"),
input_bfd, h->root.root.string);
else
(*_bfd_error_handler) (*_bfd_error_handler)
(_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"), (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
input_bfd, input_bfd, x86_64_elf_howto_table[r_type].name,
x86_64_elf_howto_table[r_type].name, h->root.root.string);
(h) ? h->root.root.string : "a local symbol");
bfd_set_error (bfd_error_bad_value); bfd_set_error (bfd_error_bad_value);
return FALSE; return FALSE;
} }