binutils-gdb/bfd/elf-linker-x86.h
H.J. Lu 68b007788a ld/x86: Add -z report-relative-reloc
Linker generated relative relocations don't have symbol info:

[hjl@gnu-cfl-2 tmpdir]$ readelf -rW dump

Relocation section '.rela.dyn' at offset 0x180 contains 2 entries:
 Offset     Info    Type                Sym. Value  Symbol's Name + Addend
00002f70  00000008 R_X86_64_RELATIVE                 1000
00002f68  00000025 R_X86_64_IRELATIVE                1007
[hjl@gnu-cfl-2 tmpdir]$

Add -z report-relative-reloc to x86 ELF linker to report dynamic relative
relocations:

[hjl@gnu-cfl-2 tmpdir]$ ../ld-new -pie -melf32_x86_64 -z report-relative-reloc -o dump report-reloc-1.o
dump: R_X86_64_IRELATIVE (offset: 0x00002f68, info: 0x00000025, addend: 0x00001007) against 'ifunc' for section '.data.rel.ro.local' in report-reloc-1.o
dump: R_X86_64_RELATIVE (offset: 0x00002f70, info: 0x00000008, addend: 0x00001000) against '_start' for section '.data.rel.ro.local' in report-reloc-1.o
[hjl@gnu-cfl-2 tmpdir]$

It can be used to map relative relocations to corresponding symbols.

bfd/

	* elf-linker-x86.h (elf_linker_x86_params): Add
	report_relative_reloc.
	* elf32-i386.c (elf_i386_relocate_section): Call
	_bfd_x86_elf_link_report_relative_reloc to report relative
	relocations for -z report-relative-reloc.
	(elf_i386_finish_dynamic_symbol): Likewse.
	* elf64-x86-64.c (elf_x86_64_relocate_section): Likewse.
	(elf_x86_64_finish_dynamic_symbol): Likewse.
	* elfxx-x86.c (_bfd_x86_elf_link_report_relative_reloc): New
	function.
	* elfxx-x86.h (_bfd_x86_elf_link_report_relative_reloc): New
	prototype.

ld/

	* NEWS: Mention -z report-relative-reloc.
	* ld.texi: Document -z report-relative-reloc.
	* emulparams/elf32_x86_64.sh: Source x86-report-relative.sh.
	* emulparams/elf_i386.sh: Likewse.
	* emulparams/elf_x86_64.sh: Likewse.
	* emulparams/x86-report-relative.sh: New file.
	* testsuite/ld-i386/report-reloc-1.d: Likewse.
	* testsuite/ld-i386/report-reloc-1.l: Likewse.
	* testsuite/ld-i386/report-reloc-1.s: Likewse.
	* testsuite/ld-x86-64/report-reloc-1-x32.d: Likewse.
	* testsuite/ld-x86-64/report-reloc-1.d: Likewse.
	* testsuite/ld-x86-64/report-reloc-1.l: Likewse.
	* testsuite/ld-x86-64/report-reloc-1.s: Likewse.
	* testsuite/ld-i386/i386.exp: Run report-reloc-1.
	* testsuite/ld-x86-64/x86-64.exp: Run report-reloc-1 and
	report-reloc-1-x32.
2021-01-15 18:07:07 -08:00

85 lines
2.9 KiB
C

/* x86-specific ELF linker support between ld and bfd.
Copyright (C) 2019-2021 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. */
/* Missing IBT, SHSTK and LAM property report control. */
enum elf_x86_prop_report
{
prop_report_none = 0, /* Do nothing. */
prop_report_warning = 1 << 0, /* Issue a warning. */
prop_report_error = 1 << 1, /* Issue an error. */
prop_report_ibt = 1 << 2, /* Report missing IBT property. */
prop_report_shstk = 1 << 3 /* Report missing SHSTK property. */
};
/* Used to pass x86-specific linker options from ld to bfd. */
struct elf_linker_x86_params
{
/* TRUE if BND prefix in PLT entries is always generated. */
unsigned int bndplt: 1;
/* TRUE if IBT-enabled PLT entries should be generated. */
unsigned int ibtplt: 1;
/* TRUE if GNU_PROPERTY_X86_FEATURE_1_IBT should be generated. */
unsigned int ibt: 1;
/* TRUE if GNU_PROPERTY_X86_FEATURE_1_SHSTK should be generated. */
unsigned int shstk: 1;
/* TRUE if GNU_PROPERTY_X86_FEATURE_1_LAM_U48 should be generated. */
unsigned int lam_u48: 1;
/* TRUE if GNU_PROPERTY_X86_FEATURE_1_LAM_U57 should be generated. */
unsigned int lam_u57: 1;
/* TRUE if we shouldn't check relocation overflow. */
unsigned int no_reloc_overflow_check: 1;
/* TRUE if generate a 1-byte NOP as suffix for x86 call instruction. */
unsigned int call_nop_as_suffix : 1;
/* TRUE if -static is passed at command-line before all input files. */
unsigned int static_before_all_inputs : 1;
/* TRUE if --dynamic-linker is passed at command-line. */
unsigned int has_dynamic_linker : 1;
/* Report relative relocations. */
unsigned int report_relative_reloc : 1;
/* X86-64 ISA level needed. */
unsigned int isa_level;
/* Report missing IBT and SHSTK properties. */
enum elf_x86_prop_report cet_report;
/* Report missing LAM_U48 property. */
enum elf_x86_prop_report lam_u48_report;
/* Report missing LAM_U57 property. */
enum elf_x86_prop_report lam_u57_report;
/* The 1-byte NOP for x86 call instruction. */
char call_nop_byte;
};
extern void _bfd_elf_linker_x86_set_options
(struct bfd_link_info *, struct elf_linker_x86_params *);