Commit Graph

12 Commits

Author SHA1 Message Date
Indu Bhagat
6e09ae77a1 sframe: doc: update spec for the mangled-RA bit in FRE
ChangeLog:

	* libsframe/doc/sframe-spec.texi
2022-12-16 22:02:11 -08:00
Indu Bhagat
49948bce0e objdump/readelf: sframe: emit marker for FREs with mangled RA
In the textual dump of the SFrame section, when an SFrame FRE recovers a
mangled RA, use string "[s]" in the output to indicate that the return
address is a signed (mangled) one.

ChangeLog:

        * libsframe/sframe-dump.c (dump_sframe_func_with_fres): Postfix
	with "[s]" if RA is signed with authorization code.
2022-12-16 22:02:02 -08:00
Indu Bhagat
9c4b163cb5 libsframe: provide new access API for mangled RA bit
include/ChangeLog:

	* sframe-api.h (sframe_fre_get_ra_mangled_p): New declaration.

ChangeLog:

	* libsframe/sframe.c (sframe_get_fre_ra_mangled_p): New
	definition.
	(sframe_fre_get_ra_mangled_p): New static function.
2022-12-16 22:01:57 -08:00
Indu Bhagat
8c078abdc2 libsframe asan: avoid generating misaligned loads
There are two places where unaligned loads were seen on aarch64:
  - #1. access to the SFrame FRE stack offsets in the in-memory
    representation/abstraction provided by libsframe.
  - #2. access to the SFrame FRE start address in the on-disk representation
    of the frame row entry.

For #1, we can fix this by reordering the struct members of
sframe_frame_row_entry in libsframe/sframe-api.h.

For #2, we need to default to using memcpy instead, and copy out the bytes
to a location for output.

SFrame format is an unaligned on-disk format. As such, there are other blobs
of memory in the on-disk SFrame FRE that are on not on their natural
boundaries.  But that does not pose further problems yet, because the users
are provided access to the on-disk SFrame FRE data via libsframe's
sframe_frame_row_entry, the latter has its' struct members aligned on their
respective natural boundaries (and initialized using memcpy).

PR 29856 libsframe asan: load misaligned at sframe.c:516

ChangeLog:

	PR libsframe/29856
	* bfd/elf64-x86-64.c: Adjust as the struct members have been
	reordered.
	* libsframe/sframe.c (sframe_decode_fre_start_address): Use
	memcpy to perform 16-bit/32-bit reads.
	* libsframe/testsuite/libsframe.encode/encode-1.c: Adjust as the
	struct members have been reordered.

include/ChangeLog:

	PR libsframe/29856
	* sframe-api.h: Reorder fre_offsets for natural alignment.
2022-12-15 13:12:01 -08:00
Indu Bhagat
b659fb3585 libsframe: rename API sframe_fde_func_info to sframe_fde_create_func_info
The new name better reflects the purpose of the function.

ChangeLog:

	* bfd/elfxx-x86.c (_bfd_x86_elf_create_sframe_plt): Use new
	name.
	* libsframe/sframe.c (sframe_fde_create_func_info): Rename
	sframe_fde_func_info to this.
	* libsframe/testsuite/libsframe.encode/encode-1.c: Use new name.

include/ChangeLog:

	* sframe-api.h (sframe_fde_create_func_info): Rename
	sframe_fde_func_info to this.
2022-12-09 10:25:31 -08:00
Indu Bhagat
3f107464e3 sframe: gas: libsframe: define constants and remove magic numbers
Define constants in sframe.h for the various limits associated with the
range of offsets that can be encoded in the start address of an SFrame
FRE. E.g., sframe_frame_row_entry_addr1 is used when start address
offset can be encoded as 1-byte unsigned value.

Update the code in gas to use these defined constants as it checks for
these limits, and remove the usage of magic numbers.

ChangeLog:

	* gas/sframe-opt.c (sframe_estimate_size_before_relax):
	(sframe_convert_frag): Do not use magic numbers.
	* libsframe/sframe.c (sframe_calc_fre_type): Likewise.

include/ChangeLog:

	* sframe.h (SFRAME_FRE_TYPE_ADDR1_LIMIT): New constant.
	(SFRAME_FRE_TYPE_ADDR2_LIMIT): Likewise.
	(SFRAME_FRE_TYPE_ADDR4_LIMIT): Likewise.
2022-12-09 10:23:07 -08:00
Indu Bhagat
1e2a61ef2d libsframe: minor formatting nits
ChangeLog:

	* libsframe/sframe.c: Fix formatting nits.
2022-12-09 10:21:57 -08:00
Indu Bhagat
cbff1430f8 sframe/doc: remove usage of xrefautomaticsectiontitle
xrefautomaticsectiontitle appears to be available from texinfo 5.0 or
greater.  As such, it is not worthwhile to add requirement for a minimum
necessary makeinfo version.  So remove the usage of it.

Also align node name with section title where possible.

ChangeLog:

	* libsframe/doc/sframe-spec.texi: Remove usage of
	xrefautomaticsectiontitle.
2022-11-24 10:14:08 -08:00
Indu Bhagat
c1c57352f5 doc: add SFrame spec file
ChangeLog:

	* libsframe/Makefile.am: Add info-in-builddir to
	  AUTOMAKE_OPTIONS. Include doc/local.mk.
	* libsframe/Makefile.in: Regenerated.
	* libsframe/configure: Likewise.
	* libsframe/configure.ac: Check for makeinfo and set BUILD_INFO.
	* libsframe/doc/local.mk: New file.
	* libsframe/doc/sframe-spec.texi: Likewise.
2022-11-15 15:50:05 -08:00
Indu Bhagat
42b6953bba readelf/objdump: support for SFrame section
This patch adds support for SFrame in readelf and objdump. The arguments
of --sframe are optional for both readelf and objdump.

include/ChangeLog:

	* sframe-api.h (dump_sframe): New function declaration.

ChangeLog:

	* binutils/Makefile.am: Add dependency on libsframe for
	readelf and objdump.
	* binutils/Makefile.in: Regenerate.
	* binutils/doc/binutils.texi: Document --sframe=[section].
	* binutils/doc/sframe.options.texi: New file.
	* binutils/objdump.c: Add support for SFrame format.
	* binutils/readelf.c: Likewise.
	* include/sframe-api.h: Add new API for dumping .sframe
	section.
	* libsframe/Makefile.am: Add sframe-dump.c.
	* libsframe/Makefile.in: Regenerate.
	* libsframe/sframe-dump.c: New file.
2022-11-15 15:50:05 -08:00
Indu Bhagat
cf0e0a0ba9 bfd: linker: merge .sframe sections
The linker merges all the input .sframe sections.  When merging, the
linker verifies that all the input .sframe sections have the same
abi/arch.

The linker uses libsframe library to perform key actions on the
.sframe sections - decode, read, and create output data.  This
implies buildsystem changes to make and install libsframe before
libbfd.

The linker places the output .sframe section in a new segment of its
own: PT_GNU_SFRAME.  A new segment is not added, however, if the
generated .sframe section is empty.

When a section is discarded from the final link, the corresponding
entries in the .sframe section for those functions are also deleted.

The linker sorts the SFrame FDEs on start address by default and sets
the SFRAME_F_FDE_SORTED flag in the .sframe section.

This patch also adds support for generation of SFrame unwind
information for the .plt* sections on x86_64.  SFrame unwind info is
generated for IBT enabled PLT, lazy/non-lazy PLT.

The existing linker option --no-ld-generated-unwind-info has been
adapted to include the control of whether .sframe unwind information
will be generated for the linker generated sections like PLT.

Changes to the linker script have been made as necessary.

ChangeLog:

	* Makefile.def: Add install dependency on libsframe for libbfd.
	* Makefile.in: Regenerated.
	* bfd/Makefile.am: Add elf-sframe.c
	* bfd/Makefile.in: Regenerated.
	* bfd/bfd-in2.h (SEC_INFO_TYPE_SFRAME): Regenerated.
	* bfd/configure: Regenerate.
	* bfd/configure.ac: Add elf-sframe.lo.
	* bfd/elf-bfd.h (struct sframe_func_bfdinfo): New struct.
	(struct sframe_dec_info): Likewise.
	(struct sframe_enc_info): Likewise.
	(struct elf_link_hash_table): New member for encoded .sframe
	object.
	(struct output_elf_obj_tdata): New member.
	(elf_sframe): New access macro.
	(_bfd_elf_set_section_sframe): New declaration.
	* bfd/elf.c (get_segment_type): Handle new segment
	PT_GNU_SFRAME.
	(bfd_section_from_phdr): Likewise.
	(get_program_header_size): Likewise.
	(_bfd_elf_map_sections_to_segments): Likewise.
	* bfd/elf64-x86-64.c (elf_x86_64_link_setup_gnu_properties): Add
	contents to the .sframe sections or .plt* entries.
	* bfd/elflink.c (elf_section_ignore_discarded_relocs): Handle
	SEC_INFO_TYPE_SFRAME.
	(_bfd_elf_default_action_discarded): Handle .sframe section.
	(elf_link_input_bfd): Merge .sframe section.
	(bfd_elf_final_link): Write the output .sframe section.
	(bfd_elf_discard_info): Handle discarding .sframe section.
	* bfd/elfxx-x86.c (_bfd_x86_elf_size_dynamic_sections): Create
	.sframe section for .plt and .plt.sec.
	(_bfd_x86_elf_finish_dynamic_sections): Handle .sframe from
	.plt* sections.
	* bfd/elfxx-x86.h (PLT_SFRAME_FDE_START_OFFSET): New
	definition.
	(SFRAME_PLT0_MAX_NUM_FRES): Likewise.
	(SFRAME_PLTN_MAX_NUM_FRES): Likewise.
	(struct elf_x86_sframe_plt): New structure.
	(struct elf_x86_link_hash_table): New member.
	(struct elf_x86_init_table): New members for .sframe
	creation.
	* bfd/section.c: Add new definition SEC_INFO_TYPE_SFRAME.
	* binutils/readelf.c (get_segment_type): Handle new segment
	PT_GNU_SFRAME.
	* ld/ld.texi: Update documentation for
	--no-ld-generated-unwind-info.
	* ld/scripttempl/elf.sc: Support .sframe sections.
	* ld/Makefile.am (TESTSFRAMELIB): Use it.
	(check-DEJAGNU): Likewise.
	* ld/Makefile.in: Regenerated.
	* ld/configure.ac (TESTSFRAMELIB): Set to the .so or .a like TESTBFDLIB.
	* ld/configure: Regenerated.
	* bfd/elf-sframe.c: New file.

include/ChangeLog:

	* elf/common.h (PT_GNU_SFRAME): New definition.
	* elf/internal.h (struct elf_segment_map): Handle new segment
	type PT_GNU_SFRAME.

ld/testsuite/ChangeLog:

	* ld/testsuite/ld-bootstrap/bootstrap.exp: Add SFRAMELIB.
	* ld/testsuite/ld-aarch64/aarch64-elf.exp: Add new test
	  sframe-simple-1.
	* ld/testsuite/ld-aarch64/sframe-bar.s: New file.
	* ld/testsuite/ld-aarch64/sframe-foo.s: Likewise.
	* ld/testsuite/ld-aarch64/sframe-simple-1.d: Likewise.
	* ld/testsuite/ld-sframe/sframe-empty.d: New test.
	* ld/testsuite/ld-sframe/sframe-empty.s: New file.
	* ld/testsuite/ld-sframe/sframe.exp: New testsuite.
	* ld/testsuite/ld-x86-64/sframe-bar.s: New file.
	* ld/testsuite/ld-x86-64/sframe-foo.s: Likewise.
	* ld/testsuite/ld-x86-64/sframe-simple-1.d: Likewise.
	* ld/testsuite/ld-x86-64/sframe-plt-1.d: Likewise.
	* ld/testsuite/ld-x86-64/sframe-simple-1.d: Likewise.
	* ld/testsuite/ld-x86-64/x86-64.exp: Add new tests -
	  sframe-simple-1, sframe-plt-1.
	* ld/testsuite/lib/ld-lib.exp: Add new proc to check if
	  assembler supports SFrame section.
	* ld/testsuite/ld-sframe/discard.d: New file.
	* ld/testsuite/ld-sframe/discard.ld: Likewise.
	* ld/testsuite/ld-sframe/discard.s: Likewise.
2022-11-15 15:49:47 -08:00
Weimin Pan
19e559f1c9 libsframe: add the SFrame library
libsframe is a library that allows you to:
- decode a .sframe section
- probe and inspect a .sframe section
- encode (and eventually write) a .sframe section.

This library is currently being used by the linker, readelf, objdump.
This library will also be used by the SFrame unwinder which is still
to be upstream'd.

The file include/sframe-api.h defines the user-facing APIs for decoding,
encoding and probing .sframe sections. A set of error codes together
with their error message strings are also defined.

Endian flipping is performed automatically at read and write time, if
cross-endianness is detected.

ChangeLog:

	* Makefile.def: Add libsframe as new module with its
	dependencies.
	* Makefile.in: Regenerated.
	* binutils/Makefile.am: Add libsframe.
	* binutils/Makefile.in: Regenerated.
	* configure: Regenerated
	* configure.ac: Add libsframe to host_libs.
	* libsframe/Makefile.am: New file.
	* libsframe/Makefile.in: New file.
	* libsframe/aclocal.m4: New file.
	* libsframe/config.h.in: New file.
	* libsframe/configure: New file.
	* libsframe/configure.ac: New file.
	* libsframe/sframe-error.c: New file.
	* libsframe/sframe-impl.h: New file.
	* libsframe/sframe.c: New file.

include/ChangeLog:

	* sframe-api.h: New file.

testsuite/ChangeLog:

	* libsframe/testsuite/Makefile.am: New file.
	* libsframe/testsuite/Makefile.in: Regenerated.
	* libsframe/testsuite/libsframe.decode/Makefile.am: New
	  file.
	* libsframe/testsuite/libsframe.decode/Makefile.in:
	  Regenerated.
	* libsframe/testsuite/libsframe.decode/decode.exp: New file.
	* libsframe/testsuite/libsframe.encode/Makefile.am:
	  Likewise.
	* libsframe/testsuite/libsframe.encode/Makefile.in:
	  Regenerated.
	* libsframe/testsuite/libsframe.encode/encode.exp: New file.
	* libsframe/testsuite/libsframe.encode/encode-1.c: Likewise.
	* libsframe/testsuite/libsframe.decode/be-flipping.c: Likewise.
	* libsframe/testsuite/libsframe.decode/frecnt-1.c: Likewise.
	* libsframe/testsuite/libsframe.decode/frecnt-2.c: Likewise.
	* libsframe/testsuite/libsframe.decode/DATA-BE: New file.
	* libsframe/testsuite/libsframe.decode/DATA1: Likewise.
	* libsframe/testsuite/libsframe.decode/DATA2: Likewise.
2022-11-15 15:24:29 -08:00