This is part of the patch series to add support for BTI and
PAC in AArch64 linker.
1) This patch adds new definitions of PAC enabled PLTs
and both BTI and PAC enabled PLTs.
2) It also defines the new dynamic tag DT_AARCH64_PAC_PLT
for the PAC enabled PLTs.
3) This patch adds a new ld command line option: --pac-plt.
In the presence of this option, the linker uses the PAC
enabled PLTs and marks with DT_AARCH64_PAC_PLT.
4) In case both BTI and PAC are enabled the linker should
pick PLTs enabled with both and also use dynamic tags for both.
All these are made according to the new AArch64 ELF ABI
https://developer.arm.com/docs/ihi0056/latest/elf-for-the-arm-64-bit-architecture-aarch64-abi-2018q4
*** bfd/ChangeLog ***
2019-03-13 Sudakshina Das <sudi.das@arm.com>
* elfnn-aarch64.c (PLT_PAC_ENTRY_SIZE, PLT_PAC_SMALL_ENTRY_SIZE): New.
(PLT_BTI_PAC_ENTRY_SIZE, PLT_BTI_PAC_SMALL_ENTRY_SIZE): New.
(setup_plt_values): Account for PAC or PAC and BTI enabled PLTs.
(elfNN_aarch64_size_dynamic_sections): Add checks for PLT_BTI_PAC
and PLT_PAC_PLT.
(elfNN_aarch64_finish_dynamic_sections): Account for PLT_BTI_PAC.
(get_plt_type): Add case for DT_AARCH64_PAC_PLT.
(elfNN_aarch64_plt_sym_val): Add cases for PLT_BTI_PAC and PLT_PAC.
*** binutils/ChangeLog ***
2019-03-13 Sudakshina Das <sudi.das@arm.com>
* readelf.c (get_aarch64_dynamic_type): Add case for
DT_AARCH64_PAC_PLT.
(dynamic_section_aarch64_val): Likewise.
*** include/ChangeLog ***
2019-03-13 Sudakshina Das <sudi.das@arm.com>
* elf/aarch64.h (DT_AARCH64_PAC_PLT): New.
*** ld/ChangeLog ***
2019-03-13 Sudakshina Das <sudi.das@arm.com>
* NEWS: Document --pac-plt.
* emultempl/aarch64elf.em (OPTION_PAC_PLT): New.
(PARSE_AND_LIST_LONGOPTS, PARSE_AND_LIST_OPTIONS): Add pac-plt.
(PARSE_AND_LIST_ARGS_CASES): Handle OPTION_PAC_PLT.
* testsuite/ld-aarch64/aarch64-elf.exp: Add the following tests.
* testsuite/ld-aarch64/bti-pac-plt-1.d: New test.
* testsuite/ld-aarch64/bti-pac-plt-2.d: New test.
* testsuite/ld-aarch64/pac-plt-1.d: New test.
* testsuite/ld-aarch64/pac-plt-2.d: New test.
* testsuite/ld-aarch64/bti-plt-1.s: Add .ifndef directive.
This is part of the patch series to add support for BTI and
PAC in AArch64 linker.
1) This patch adds a new ld command line option: --force-bti.
In the presence of this option, the linker enables BTI with the
GNU_PROPERTY_AARCH64_FEATURE_1_BTI feature. This gives out warning
in case of missing gnu notes for BTI in inputs.
2) It also defines a new set of BTI enabled PLTs. These are used either
when all the inputs are marked with GNU_PROPERTY_AARCH64_FEATURE_1_BTI
or when the new --force-bti option is used. This required adding new
fields in elf_aarch64_link_hash_table so that we could make the PLT
related information more generic.
3) It also defines a dynamic tag DT_AARCH64_BTI_PLT. The linker uses
this whenever it picks BTI enabled PLTs.
All these are made according to the new AArch64 ELF ABI
https://developer.arm.com/docs/ihi0056/latest/elf-for-the-arm-64-bit-architecture-aarch64-abi-2018q4
*** bfd/ChangeLog ***
2019-03-13 Sudakshina Das <sudi.das@arm.com>
Szabolcs Nagy <szabolcs.nagy@arm.com>
* bfd-in.h (aarch64_plt_type, aarch64_enable_bti_type): New.
(aarch64_bti_pac_info): New.
(bfd_elf64_aarch64_set_options): Add aarch64_bti_pac_info argument.
(bfd_elf32_aarch64_set_options): Likewise.
* bfd-in2.h: Regenerate
* elfnn-aarch64.c (PLT_BTI_ENTRY_SIZE): New.
(PLT_BTI_SMALL_ENTRY_SIZE, PLT_BTI_TLSDESC_ENTRY_SIZE): New.
(elfNN_aarch64_small_plt0_bti_entry): New.
(elfNN_aarch64_small_plt_bti_entry): New.
(elfNN_aarch64_tlsdesc_small_plt_bti_entry): New.
(elf_aarch64_obj_tdata): Add no_bti_warn and plt_type fields.
(elf_aarch64_link_hash_table): Add plt0_entry, plt_entry and
tlsdesc_plt_entry_size fields.
(elfNN_aarch64_link_hash_table_create): Initialise the new fields.
(setup_plt_values): New helper function.
(bfd_elfNN_aarch64_set_options): Use new bp_info to set plt sizes and
bti enable type.
(elfNN_aarch64_allocate_dynrelocs): Use new size members instead of
fixed macros.
(elfNN_aarch64_size_dynamic_sections): Likewise and add checks.
(elfNN_aarch64_create_small_pltn_entry): Use new generic pointers
to plt stubs instead of fixed ones and update filling them according
to the need for bti.
(elfNN_aarch64_init_small_plt0_entry): Likewise.
(elfNN_aarch64_finish_dynamic_sections): Likewise.
(get_plt_type, elfNN_aarch64_get_synthetic_symtab): New.
(elfNN_aarch64_plt_sym_val): Update size accordingly.
(elfNN_aarch64_link_setup_gnu_properties): Set up plts if BTI GNU NOTE
is set.
(bfd_elfNN_get_synthetic_symtab): Define.
(elfNN_aarch64_merge_gnu_properties): Give out warning with --force-bti
and mising BTI NOTE SECTION.
*** binutils/ChangeLog ***
2019-03-13 Sudakshina Das <sudi.das@arm.com>
Szabolcs Nagy <szabolcs.nagy@arm.com>
* readelf.c (get_aarch64_dynamic_type): New.
(get_dynamic_type): Use above for EM_AARCH64.
(dynamic_section_aarch64_val): New.
(process_dynamic_section): Use above for EM_AARCH64.
*** include/ChangeLog ***
2019-03-13 Sudakshina Das <sudi.das@arm.com>
Szabolcs Nagy <szabolcs.nagy@arm.com>
* elf/aarch64.h (DT_AARCH64_BTI_PLT): New.
*** ld/ChangeLog ***
2019-03-13 Sudakshina Das <sudi.das@arm.com>
Szabolcs Nagy <szabolcs.nagy@arm.com>
* NEWS: Document --force-bti.
* emultempl/aarch64elf.em (plt_type, bti_type, OPTION_FORCE_BTI): New.
(PARSE_AND_LIST_SHORTOPTS, PARSE_AND_LIST_OPTIONS): Add force-bti.
(PARSE_AND_LIST_ARGS_CASES): Handle OPTION_FORCE_BTI.
* testsuite/ld-aarch64/aarch64-elf.exp: Add all the tests below.
* testsuite/ld-aarch64/bti-plt-1.d: New test.
* testsuite/ld-aarch64/bti-plt-1.s: New test.
* testsuite/ld-aarch64/bti-plt-2.s: New test.
* testsuite/ld-aarch64/bti-plt-2.d: New test.
* testsuite/ld-aarch64/bti-plt-3.d: New test.
* testsuite/ld-aarch64/bti-plt-4.d: New test.
* testsuite/ld-aarch64/bti-plt-5.d: New test.
* testsuite/ld-aarch64/bti-plt-6.d: New test.
* testsuite/ld-aarch64/bti-plt-7.d: New test.
* testsuite/ld-aarch64/bti-plt-so.s: New test.
* testsuite/ld-aarch64/bti-plt.ld: New test.
This is part of the patch series to add support for BTI and
PAC in AArch64 linker.
This patch implements the following:
1) This extends in the gnu property support in the linker for
AArch64 by defining backend hooks for elf_backend_setup_gnu_properties,
elf_backend_merge_gnu_properties and elf_backend_parse_gnu_properties.
2) It defines AArch64 specific GNU property
GNU_PROPERTY_AARCH64_FEATURE_1_AND and 2 bit for BTI and PAC in it.
3) It also adds support in readelf.c to read and print these new
GNU properties in AArch64.
All these are made according to the new AArch64 ELF ABI
https://developer.arm.com/docs/ihi0056/latest/elf-for-the-arm-64-bit-architecture-aarch64-abi-2018q4
*** bfd/ChangeLog ***
2019-03-13 Sudakshina Das <sudi.das@arm.com>
* elf-properties.c (_bfd_elf_link_setup_gnu_properties): Exclude
linker created inputs from merge.
* elfnn-aarch64.c (struct elf_aarch64_obj_tdata): Add field for
GNU_PROPERTY_AARCH64_FEATURE_1_AND properties.
(elfNN_aarch64_link_setup_gnu_properties): New.
(elfNN_aarch64_merge_gnu_properties): New.
(elf_backend_setup_gnu_properties): Define for AArch64.
(elf_backend_merge_gnu_properties): Likewise.
* elfxx-aarch64.c (_bfd_aarch64_elf_link_setup_gnu_properties): Define.
(_bfd_aarch64_elf_parse_gnu_properties): Define.
(_bfd_aarch64_elf_merge_gnu_properties): Define.
* elfxx-aarch64.h (_bfd_aarch64_elf_link_setup_gnu_properties): Declare.
(_bfd_aarch64_elf_parse_gnu_properties): Declare.
(_bfd_aarch64_elf_merge_gnu_properties): Declare.
(elf_backend_parse_gnu_properties): Define for AArch64.
*** binutils/ChangeLog ***
2019-03-13 Sudakshina Das <sudi.das@arm.com>
* readelf.c (decode_aarch64_feature_1_and): New.
(print_gnu_property_note): Add case for AArch64 gnu notes.
*** include/ChangeLog ***
2019-03-13 Sudakshina Das <sudi.das@arm.com>
* elf/common.h (GNU_PROPERTY_AARCH64_FEATURE_1_AND): New.
(GNU_PROPERTY_AARCH64_FEATURE_1_BTI): New.
(GNU_PROPERTY_AARCH64_FEATURE_1_PAC): New.
*** ld/ChangeLog ***
2019-03-13 Sudakshina Das <sudi.das@arm.com>
* NEWS: Document GNU_PROPERTY_AARCH64_FEATURE_1_BTI and
GNU_PROPERTY_AARCH64_FEATURE_1_PAC.
* testsuite/ld-aarch64/aarch64-elf.exp: Add run commands for new tests.
* testsuite/ld-aarch64/property-bti-pac1.d: New test.
* testsuite/ld-aarch64/property-bti-pac1.s: New test.
* testsuite/ld-aarch64/property-bti-pac2.d: New test.
* testsuite/ld-aarch64/property-bti-pac2.s: New test.
* testsuite/ld-aarch64/property-bti-pac3.d: New test.
There should be no AND properties if some input doesn't have them. We
should set IBT and SHSTK properties for -z ibt and -z shstk if needed.
bfd/
PR ld/24322
* elfxx-x86.c (_bfd_x86_elf_merge_gnu_properties): Properly
merge GNU_PROPERTY_X86_FEATURE_1_[IBT|SHSTK].
ld/
PR ld/24322
* testsuite/ld-i386/i386.exp: Run PR ld/24322 tests.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/pr24322a.d: New file.
* testsuite/ld-i386/pr24322b.d: Likewise.
* testsuite/ld-x86-64/pr24322a-x32.d: Likewise.
* testsuite/ld-x86-64/pr24322a.d: Likewise.
* testsuite/ld-x86-64/pr24322b-x32.d: Likewise.
* testsuite/ld-x86-64/pr24322b.d: Likewise.
* testsuite/ld-x86-64/pr24322a.s: Likewise.
* testsuite/ld-x86-64/pr24322b.s: Likewise.
* testsuite/ld-x86-64/pr24322c.s: Likewise.
Compressed debug sections can have uncompressed sizes that exceed the
original file size, so we can't use bfd_get_file_size. objdump also
used bfd_get_file_size to limit reloc section size, but I believe the
underlying bug causing the PR22508 out of bounds buffer access was
that we had an integer overflow when calculating the reloc buffer
size. I've fixed that instead in most of the backends, som and
vms-alpha being the exceptions. SOM and vmd-alpha have rather more
serious bugs in their slurp_relocs routines that would need fixing
first if we want to fuss about making them safe against fuzzed object
files.
The patch also fixes a number of other potential overflows by using
the bfd_alloc2/malloc2/zalloc2 memory allocation functions.
bfd/
* coffcode.h (buy_and_read): Delete unnecessary forward decl. Add
nmemb parameter. Use bfd_alloc2.
(coff_slurp_line_table): Use bfd_alloc2. Update buy_and_read calls.
Delete assertion.
(coff_slurp_symbol_table): Use bfd_alloc2 and bfd_zalloc2.
(coff_slurp_reloc_table): Use bfd_alloc2. Update buy_and_read calls.
* coffgen.c (coff_get_reloc_upper_bound): Ensure size calculation
doesn't overflow.
* elf.c (bfd_section_from_shdr): Use bfd_zalloc2. Style fix.
(assign_section_numbers): Style fix.
(swap_out_syms): Use bfd_malloc2.
(_bfd_elf_get_reloc_upper_bound): Ensure size calculation doesn't
overflow.
(_bfd_elf_make_empty_symbol): Style fix.
(elfobj_grok_stapsdt_note_1): Formatting.
* elfcode.h (elf_object_p): Use bfd_alloc2.
(elf_write_relocs, elf_write_shdrs_and_ehdr): Likewise.
(elf_slurp_symbol_table): Use bfd_zalloc2.
(elf_slurp_reloc_table): Use bfd_alloc2.
(_bfd_elf_bfd_from_remote_memory): Use bfd_malloc2.
* elf64-sparc (elf64_sparc_get_reloc_upper_bound): Ensure
size calculation doesn't overflow.
(elf64_sparc_get_dynamic_reloc_upper_bound): Likewise.
* mach-o.c (bfd_mach_o_get_reloc_upper_bound): Likewise.
* pdp11.c (get_reloc_upper_bound): Copy aoutx.h version.
binutils/
* objdump.c (load_specific_debug_section): Don't compare section
size against file size.
(dump_relocs_in_section): Don't compare reloc size against file size.
Print "failed to read relocs" on bfd_get_reloc_upper_bound error.
Not padding string merge section output to its alignment can cause
failures of the S-record tests when input string merge sections are
padded, since the ELF linker output for the single string section
would shrink compared to the SREC linker output. That might result in
following sections having different addresses.
On the other hand, padding string merge section output when input
string merge sections are *not* padded can also cause failures, in
this case due to the ELF linker output for the string section being
larger (due to padding) than the SREC linker output.
It would be better to write a more robust test, but it is also nice
to leave input unchanged when no string merges occur.
PR 24311
* merge.c (merge_strings): Return secinfo. Don't pad section
to alignment here.
(_bfd_merge_sections): Pad section to alignment here, if input
sections contributing to merged output all pad to alignment.
Formatting.
* dwarf2.c (_bfd_dwarf2_find_symbol_bias): Check for a NULL symbol
table pointer.
* coffgen.c (coff_find_nearest_line_with_names): Do not call
_bfd_dwarf2_find_symbol_bias if there is no symbol table available.
https://bugzilla.redhat.com/show_bug.cgi?id=1685727
According to the specification for the CIE entries, when the CIE version is 1 then
the return address register field is always 1 byte. Readelf does this correctly in
read_cie in dwarf.c but ld does this incorrectly and always tries to read a
skip_leb128. If the value here has the top bit set then ld will incorrectly read
at least another byte, causing either an assert failure or an incorrect address to
be used in eh_frame.
I'm not sure how to generate a generic test for this as I'd need to write assembly,
and it's a bit hard to trigger. Essentially the relocated value needs to start with
something that & 0x70 != 0x10 while trying to write a personality.
bfd/ChangeLog:
* elf-eh-frame.c (_bfd_elf_write_section_eh_frame): Correct CIE parse.
The fix here is to use an unsigned comparison for
if (a->NumberOfRvaAndSizes > IMAGE_NUMBEROF_DIRECTORY_ENTRIES)
include/
PR 24272
* coff/internal.h (struct internal_extra_pe_aouthdr): Change type
of SizeOfCode, SizeOfInitializedData, and SizeOfUninitializedData
to bfd_vma. Change type of SectionAlignment, FileAlignment,
Reserved1, SizeOfImage, SizeOfHeaders, CheckSum, LoaderFlags,
and NumberOfRvaAndSizes to uint32_t.
bfd/
PR 24272
* peXXigen.c (_bfd_XXi_swap_aouthdr_in): Use unsigned index.
(_bfd_XX_print_private_bfd_data_common): Adjust for type changes.
Skip symbol defined by linker when checking copy reloc on protected
symbol.
bfd/
PR ld/24276
* elf64-x86-64.c (elf_x86_64_check_relocs): Skip symbol defined
by linker when checking copy reloc on protected symbol.
ld/
PR ld/24276
* testsuite/ld-i386/i386.exp: Run PR ld/24276 test.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/pr24276.dso: New file.
* testsuite/ld-i386/pr24276.warn: Likewise.
* testsuite/ld-x86-64/pr24276.dso: Likewise.
* testsuite/ld-x86-64/pr24276.warn: Likewise.
Big section alignment requirements between source and destination of a
long call can result in making call range bigger than what's reachable
by the call opcode. Add biggest section alignment of sections between
the call site and call destination to the call distance when making
long call relaxation decision.
2019-02-20 Eric Tsai <erictsai@cadence.com>
bfd/
* elf32-xtensa.c (is_resolvable_asm_expansion): Scan output
sections between the call site and call destination and adjust
call distance by the largest alignment.
ld/
* testsuite/ld-xtensa/call_overflow.d: New test definition.
* testsuite/ld-xtensa/call_overflow1.s: New test source.
* testsuite/ld-xtensa/call_overflow2.s: New test source.
* testsuite/ld-xtensa/call_overflow3.s: New test source.
* testsuite/ld-xtensa/xtensa.exp: Add call_overflow test.
Used for the AArch64 pointer authentication code mask registers in Arm v8.3-a.
NT_ARM_PAC_MASK matches the value in Linux include/uapi/linux/elf.h
include/ChangeLog:
* elf/common.h (NT_ARM_PAC_MASK): Add define.
bfd/ChangeLog:
* elf-bfd.h (elfcore_write_aarch_pauth): Add declaration.
* elf.c (elfcore_grok_aarch_pauth): New function.
(elfcore_grok_note): Check for NT_ARM_PAC_MASK.
(elfcore_write_aarch_pauth): New function.
(elfcore_write_register_note): Check for AArch64 pauth section.
git a31b8bd9a0 introduced a warning (depending on your system
headers).
PR 24225
* elf32-nios2.c (nios2_elf32_relocate_section): Check asprintf
return value.
PR 24236
* archive64.c (_bfd_archive_64_bit_slurp_armap): Move code adding
sentinel NUL to string buffer nearer to loop where it is used.
Don't go past sentinel when scanning strings, and don't write
NUL again.
* archive.c (do_slurp_coff_armap): Simplify string handling to
archive64.c style.
GDB Administrator
Sudakshina Das
H.J. Lu
Alan Modra
Nick Clifton
Andreas Krebbel
Tamar Christina
Max Filippov
Alan Hayward
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