Adjusting the start of the relro segment in order to make it end
exactly on a page boundary runs into difficulties when sections in the
relro segment are aligned; Adjusting the start by (next_page - end)
sometimes results in more than that adjustment occurring at the end,
overrunning the page boundary. So when that occurs we try a new lower
start position by masking the adjusted start with the maximum section
alignment. However, we didn't consider that this masked start address
may in fact be before the initial relro base, which is silly since
that can only increase padding at the relro end.
I've also moved some calculations closer to where they are used, and
comments closer to the relevant statements.
* ldlang.c (lang_size_sections): When alignment of sections
results in relro base adjustment being too large, don't go lower
than the initial value.
* ldexp.c (fold_binary <DATA_SEGMENT_RELRO_END>): Comment.
* scripttempl/elf.sc (DATA_SEGMENT_ALIGN): Omit SEGMENT_SIZE
alignment when SEGMENT_SIZE is the same as MAXPAGESIZE.
.toc1 is the second level TOC section used by gcc's -mminimal-toc. It
too should be read-only after relocation. Also, the last patch
description mentioned .sbss moving but didn't actually do that, so fix
that problem. .tocbss (whatever that is) was before .sbss previously,
so move that one too.
* emulparams/elf64ppc.sh (OTHER_SDATA_SECTIONS): Use in place of..
(OTHER_BSS_SYMBOLS): ..this.
(OTHER_PLT_RELOC_SECTIONS): Don't define.
(OTHER_GOT_RELOC_SECTIONS): Add rela.toc1 and rela.tocbss.
(OTHER_READWRITE_SECTIONS): Don't define. Move .toc1 to..
(OTHER_RELRO_SECTIONS_2): ..here.
* scripttempl/elf.sc: Move SBSS too when DATA_SDATA.
This moves .got too, which requires .sdata and .sbss to move with it,
because these sections share addressing via the toc pointer and with
small-model code must be within a 16-bit signed offset. .plt, .iplt
and .branch_lt must also be moved since they are addressed via a
32-bit offset from the toc pointer, and we might have a very large
.data section.
This change means we may have some bss style sections before the data
segment, necessitating another PT_LOAD header. Also, since _edata is
defined at the end of the data segment it's possible with an empty
.data to have _edata at the end of .plt which looks a little unusual
since .plt is a bss style section. That should only happen rarely in
real world binaries, but does occur in the ld testsuite.
ld/
* emulparams/elf64ppc.sh (BSS_PLT): Don't define.
(OTHER_READWRITE_SECTIONS): Move .branch_lt to..
(OTHER_RELRO_SECTIONS_2): ..here.
(DATA_GOT, SEPARATE_GOTPLT, DATA_SDATA, DATA_PLT,
PLT_BEFORE_GOT): Define.
* scripttempl/elf.sc: Handle DATA_SDATA and DATA_GOT/DATA_PLT/
PLT_BEFORE_GOT combination.
(DATA_GOT, SDATA_GOT): Don't define if either is already defined.
ld/testsuite/
* ld-powerpc/ambiguousv1.d,
* ld-powerpc/ambiguousv1b.d,
* ld-powerpc/ambiguousv2.d,
* ld-powerpc/ambiguousv2b.d,
* ld-powerpc/elfv2exe.d,
* ld-powerpc/elfv2so.d,
* ld-powerpc/tlsexe.r,
* ld-powerpc/tlsexetoc.r,
* ld-powerpc/tlsso.r,
* ld-powerpc/tlstocso.r: Update.
More sections can be read-only after relocation. .opd is an obvious
candidate.
* emulparams/elf64ppc.sh (OTHER_READWRITE_SECTIONS): Move .opd to..
(OTHER_RELRO_SECTIONS_2): ..here, new define.
* scripttempl/elf.sc: Add OTHER_RELRO_SECTIONS_2.
and fix more nds32 dependencies.
* scripttempl/elf.sc: Edit out __rela_iplt symbol assignments from
.rel sections, and __rel_iplt from .rela sections.
* scripttempl/nds32elf.sc: Likewise.
* Makefile.am (ends32*.c): Depend on nds32elf.sc.
* Makefile.in: Regenerate.
* elfxx-mips.h (_bfd_mips_elf_get_synthetic_symtab): New
prototype.
* elf32-mips.c (elf_backend_plt_sym_val): Remove macro.
(bfd_elf32_get_synthetic_symtab): New macro.
* elfxx-mips.c (plt_entry): New structure.
(mips_elf_link_hash_entry): Add use_plt_entry member.
(mips_elf_link_hash_table): Rename plt_entry_size member to
plt_mips_entry_size. Add plt_comp_entry_size, plt_mips_offset,
plt_comp_offset, plt_got_index entries and plt_header_is_comp
members.
(STUB_LW_MICROMIPS, STUB_MOVE_MICROMIPS): New macros.
(STUB_LUI_MICROMIPS, STUB_JALR_MICROMIPS): Likewise.
(STUB_ORI_MICROMIPS, STUB_LI16U_MICROMIPS): Likewise.
(STUB_LI16S_MICROMIPS): Likewise.
(MICROMIPS_FUNCTION_STUB_NORMAL_SIZE): Likewise.
(MICROMIPS_FUNCTION_STUB_BIG_SIZE): Likewise.
(micromips_o32_exec_plt0_entry): New variable.
(mips16_o32_exec_plt_entry): Likewise.
(micromips_o32_exec_plt_entry): Likewise.
(mips_elf_link_hash_newfunc): Initialize use_plt_entry.
(mips_elf_output_extsym): Update to use gotplt_union's plist
member rather than offset.
(mips_elf_gotplt_index): Likewise. Remove the VxWorks
restriction. Use MIPS_ELF_GOT_SIZE to calculate GOT address.
(mips_elf_count_got_symbols): Update to use gotplt_union's plist
member rather than offset.
(mips_elf_calculate_relocation): Handle MIPS16/microMIPS PLT
entries.
(_bfd_mips_elf_create_dynamic_sections): Don't set PLT sizes
here.
(mips_elf_make_plt_record): New function.
(_bfd_mips_elf_check_relocs): Update comment. Record occurences
of JAL relocations that might need a PLT entry.
(_bfd_mips_elf_adjust_dynamic_symbol): Update to use
gotplt_union's plist member rather than offset. Set individual
PLT entry sizes here. Handle MIPS16/microMIPS PLT entries.
Don't set the symbol's value in the symbol table for PLT
references here. Don't set the PLT or PLT GOT section sizes
here.
(mips_elf_estimate_stub_size): Handle microMIPS stubs.
(mips_elf_allocate_lazy_stub): Likewise.
(mips_elf_lay_out_lazy_stubs): Likewise. Define a _MIPS_STUBS_
magic symbol.
(mips_elf_set_plt_sym_value): New function.
(_bfd_mips_elf_size_dynamic_sections): Set PLT header size and
PLT and PLT GOT section sizes here. Set the symbol values in
the symbol table for PLT references here. Handle microMIPS
annotation of the _PROCEDURE_LINKAGE_TABLE_ magic symbol.
(_bfd_mips_elf_finish_dynamic_symbol): Update to use
gotplt_union's plist member rather than offset. Handle
MIPS16/microMIPS PLT entries. Handle microMIPS stubs.
(_bfd_mips_vxworks_finish_dynamic_symbol): Update to use
gotplt_union's plist member rather than offset. Use
MIPS_ELF_GOT_SIZE to calculate GOT address.
(mips_finish_exec_plt): Handle microMIPS PLT. Return status.
(_bfd_mips_elf_finish_dynamic_sections): Handle result from
mips_finish_exec_plt.
(_bfd_mips_elf_link_hash_table_create): Update to use
gotplt_union's plist member rather than offset.
(_bfd_mips_elf_get_synthetic_symtab): New function.
include/elf/
* mips.h (ELF_ST_IS_MIPS_PLT): Respect STO_MIPS16 setting.
(ELF_ST_SET_MIPS_PLT): Likewise.
gdb/
* mips-tdep.c (mips_elf_make_msymbol_special): Handle MIPS16 and
microMIPS synthetic symbols.
ld/
* emulparams/elf32btsmip.sh: Arrange for .got.plt to be placed
as close to .plt as possible.
* scripttempl/elf.sc: Handle $INITIAL_READWRITE_SECTIONS and
$PLT_NEXT_DATA variables.
ld/testsuite/
* ld-mips-elf/jalx-2.dd: Update for microMIPS PLT support.
* ld-mips-elf/pic-and-nonpic-3a.dd: Update for the _MIPS_STUBS_
magic symbol.
* ld-mips-elf/pic-and-nonpic-3b.dd: Likewise.
* ld-mips-elf/pic-and-nonpic-6-n32.dd: Likewise.
* ld-mips-elf/pic-and-nonpic-6-n64.dd: Likewise.
* ld-mips-elf/pic-and-nonpic-6-o32.dd: Likewise.
* ld-mips-elf/stub-dynsym-1-10000.d: Likewise.
* ld-mips-elf/stub-dynsym-1-2fe80.d: Likewise.
* ld-mips-elf/stub-dynsym-1-7fff.d: Likewise.
* ld-mips-elf/stub-dynsym-1-8000.d: Likewise.
* ld-mips-elf/stub-dynsym-1-fff0.d: Likewise.
* ld-mips-elf/tlslib-o32.d: Likewise.
opcodes/
* mips-dis.c (is_mips16_plt_tail): New function.
(print_insn_mips16): Handle MIPS16 PLT entry's GOT slot address
word.
(is_compressed_mode_p): Handle MIPS16/microMIPS PLT entries.
2009-06-06 H.J. Lu <hongjiu.lu@intel.com>
* elf32-i386.c (elf_i386_link_hash_table): Add irelifunc.
(elf_i386_link_hash_table_create): Initialize irelifunc.
(elf_i386_check_relocs): Updated. Set up irelifunc for
shared objects.
(elf_i386_allocate_dynrelocs): Use irelifunc for dynamic
relocation for non-GOT reference of STT_GNU_IFUNC symbol in
shared objects.
(elf_i386_relocate_section): Likewise.
* elf64-x86-64.c (elf64_x86_64_link_hash_table): Add irelifunc.
(elf64_x86_64_link_hash_table_create): Initialize irelifunc.
(elf64_x86_64_check_relocs): Updated. Set up irelifunc for
shared objects.
(elf64_x86_64_allocate_dynrelocs): Use irelifunc for dynamic
relocation for non-GOT reference of STT_GNU_IFUNC symbol in
shared objects.
(elf64_x86_64_relocate_section): Likewise.
* elf-bfd.h (_bfd_elf_create_static_ifunc_sections): Renamed to
...
(_bfd_elf_create_ifunc_sections): This.
* elflink.c (_bfd_elf_create_static_ifunc_sections): Renamd to
...
(_bfd_elf_create_ifunc_sections): This. Create .rel[a].ifunc
for shared objects.
ld/
2009-06-06 H.J. Lu <hongjiu.lu@intel.com>
* scripttempl/elf.sc: Add .rel.ifunc and .rela.ifunc.
* common.h (STT_IFUNC): Define.
elfcpp/
* elfcpp.h (enum STT): Add STT_IFUNC.
bfd/
* syms.c (struct bfd_symbol): Add new flag BSF_INDIRECT_FUNCTION.
Remove redundant flag BFD_FORT_COMM_DEFAULT_VALUE. Renumber flags
to remove gaps.
(bfd_print_symbol_vandf): Return 'i' for BSF_INDIRECT_FUNCTION.
(bfd_decode_symclass): Likewise.
* elf.c (swap_out_syms): Translate BSF_INDIRECT_FUNCTION into
STT_IFUNC.
(elf_find_function): Treat STT_IFUNC in the same way as STT_FUNC.
(_bfd_elf_is_function_type): Likewise.
* elf32-arm.c (arm_elf_find_function): Likewise.
(elf32_arm_adjust_dynamic_symbol): Likewise.
(elf32_arm_swap_symbol_in): Likewise.
(elf32_arm_additional_program_headers): Likewise.
* elf32-i386.c (is_indirect_symbol): New function.
(elf_i386_check_relocs): Also generate dynamic relocs for
relocations against STT_IFUNC symbols.
(allocate_dynrelocs): Likewise.
(elf_i386_relocate_section): Likewise.
* elf64-x86-64.c (is_indirect_symbol): New function.
(elf64_x86_64_check_relocs): Also generate dynamic relocs for
relocations against STT_IFUNC symbols.
(allocate_dynrelocs): Likewise.
(elf64_x86_64_relocate_section): Likewise.
* elfcode.h (elf_slurp_symbol_table): Translate STT_IFUNC into
BSF_INDIRECT_FUNCTION.
* elflink.c (_bfd_elf_adjust_dynamic_reloc_section): Add support
for STT_IFUNC symbols.
(get_ifunc_reloc_section_name): New function.
(_bfd_elf_make_ifunc_reloc_section): New function.
* elf-bfd.h (struct bfd_elf_section_data): Add indirect_relocs field.
* bfd-in2.h: Regenerate.
gas/
* config/obj-elf.c (obj_elf_type): Add support for STT_IFUNC type.
* doc/as.texinfo: Document new feature.
* NEWS: Mention new feature.
gas/testsuite/
* gas/elf/type.s: Add test of STT_IFUNC symbol type.
* gas/elf/type.e: Update expected disassembly.
* gas/elf/elf.exp: Update grep of symbol types.
ld/
* NEWS: Mention new feature.
* pe-dll.c (process_def_file): Replace use of redundant
BFD_FORT_COMM_DEFAULT_VALUE with 0.
* scripttempl/elf.sc: Add .rel.ifunc.dyn and .rela.ifunc.dyn
sections.
ld/testsuite/
* ld-mips-elf/reloc-1-n32.d: Updated expected output for reloc
descriptions.
* ld-mips-elf/reloc-1-n64.d: Likewise.
* ld-i386/ifunc.d: New test.
* ld-i386/ifunc.s: Source file for the new test.
* ld-i386/i386.exp: Run the new test.
2008-01-11 Tristan Gingold <gingold@adacore.com>
Eric Botcazou <ebotcazou@adacore.com>
* ldlang.c (lang_end): Warns if the entry point is not found when
--gc-sections.
Emit an error if no root is specified when --gc-sections -r.
* ld.texinfo (Options): Document that --gc-sections is compatible
with -r and -q.
* ldmain.c (main): Do not error out if -r and --gc-sections.
* scripttempl/elf.sc: Emit ENTRY command only if relocating.
ld/testsuite:
2008-01-11 Tristan Gingold <gingold@adacore.com>
* lib/ld-lib.exp (check_gc_sections_available): Now available on
VxWorks.
* ld-gc: New directory for testing --gc-sections.
* ld-gc/gc.c: New file.
* ld-gc/gc.exp: New file.
* ld-gc/noent.s: New file.
* ld-gc/noent.d: New file.
