Sometimes DWARF info for a function is incomplete, and the function
can be retrieved by examining symbols. However, when separate debug
files are used it may be that the original file is completely
stripped of symbols. This patch teaches BFD to look at symbols from
the debug file in that case.
The patch also removes arm_elf_find_function, instead implementing
elf_backend_maybe_function_sym. arm_elf_find_function was written
before the generic _bfd_elf_find_function called maybe_function_sym.
aarch64 copied arm, so that file gets the same treatment. There is
some chance this will speed up arm and aarch64 lookup of function/line.
PR 23652
* dwarf2.c (_bfd_dwarf2_stash_syms): New function.
(_bfd_dwarf2_find_nearest_line): Use it here, passing syms to
_bfd_elf_find_function. Call _bfd_elf_find_function in cases
where _bfd_elf_find_nearest_line would do so.
* elf.c (_bfd_elf_find_nearest_line): Omit _bfd_elf_find_function
for dwarf2.
* elfxx-mips.c (_bfd_mips_elf_find_nearest_line): Similarly. Tidy.
* elf32-arm.c (elf32_arm_maybe_function_sym): New function.
(elf_backend_maybe_function_sym): Define.
(arm_elf_find_function, elf32_arm_find_nearest_line): Delete.
(bfd_elf32_find_nearest_line): Don't define.
* elfnn-aarch64.c (elfNN_aarch64_maybe_function_sym): New function.
(elf_backend_maybe_function_sym): Define.
(aarch64_elf_find_function, elfNN_aarch64_find_nearest_line): Delete.
(bfd_elfNN_find_nearest_line): Don't define.
and other tidies. I think it's better to default to passing the
section to bfd_octets_per_byte, even in cases where we know it won't
make a difference.
A number of the coff reloc functions used bfd_octets_per_byte wrongly,
not factoring it into the offset into the data buffer. As it happens,
the targets using those files always had bfd_octets_per_byte equal to
one, so there wasn't any detectable wrong behaviour. However, it is
wrong in the source and might cause trouble for anyone creating a new
target. Besides fixing that, the patch also defines OCTETS_PER_BYTE
as one in target files where that is appropriate.
bfd/
* archures.c (bfd_octets_per_byte): Tail call
bfd_arch_mach_octets_per_byte.
* coff-arm.c (OCTETS_PER_BYTE): Define.
(coff_arm_reloc): Introduce new "octets" temp. Use OCTETS_PER_BYTE
with section. Correct "addr". Remove ATTRIBUTE_UNUSED.
* coff-i386.c (coff_i386_reloc): Similarly.
* coff-mips.c (mips_reflo_reloc): Similarly.
* coff-x86_64.c (coff_amd64_reloc): Similarly.
* elf32-msp430.c (OCTETS_PER_BYTE): Define.
(rl78_sym_diff_handler): Use OCTETS_PER_BYTE, with section.
* elf32-nds32.c (nds32_elf_get_relocated_section_contents): Similarly.
* elf32-ppc.c (ppc_elf_addr16_ha_reloc): Similarly.
* elf32-pru.c (pru_elf32_do_ldi32_relocate): Similarly.
* elf32-s12z.c (opru18_reloc): Similarly.
* elf32-sh.c (sh_elf_reloc): Similarly.
* elf32-spu.c (spu_elf_rel9): Similarly.
* elf32-xtensa.c (bfd_elf_xtensa_reloc): Similarly.
* elf64-ppc.c (ppc64_elf_ha_reloc, ppc64_elf_brtaken_reloc),
(ppc64_elf_toc64_reloc): Similarly.
* bfd.c (bfd_get_section_limit): Pass section to bfd_octets_per_byte.
* cofflink.c (_bfd_coff_link_input_bfd),
(_bfd_coff_reloc_link_order): Likewise.
* elf.c (_bfd_elf_section_offset): Likewise.
* elflink.c (resolve_section, bfd_elf_perform_complex_relocation),
(elf_link_input_bfd, elf_reloc_link_order, elf_fixup_link_order),
(bfd_elf_final_link): Likewise.
* elf.c (_bfd_elf_make_section_from_shdr): Don't strncmp twice
to set SEC_ELF_OCTETS.
* reloc.c (bfd_perform_relocation): Tidy SEC_ELF_OCTETS special case.
(bfd_install_relocation): Likewise.
(_bfd_final_link_relocate): Don't recalculate octets.
* syms.c (_bfd_stab_section_find_nearest_line): Introduc new
"octets" temp.
* bfd-in2.h: Regenerate.
ld/
* ldexp.c (fold_name): Pass section to bfd_octets_per_byte.
* ldlang.c (init_opb): Don't call bfd_arch_mach_octets_per_byte
unnecessarily.
All symbols, sizes and relocations in this section are octets instead of
bytes. Required for DWARF debug sections as DWARF information is
organized in octets, not bytes.
bfd/
* section.c (struct bfd_section): New flag SEC_ELF_OCTETS.
* archures.c (bfd_octets_per_byte): New parameter sec.
If section is not NULL and SEC_ELF_OCTETS is set, one octet es
returned [ELF targets only].
* bfd.c (bfd_get_section_limit): Provide section parameter to
bfd_octets_per_byte.
* bfd-in2.h: regenerate.
* binary.c (binary_set_section_contents): Move call to
bfd_octets_per_byte into section loop. Provide section parameter
to bfd_octets_per_byte.
* coff-arm.c (coff_arm_reloc): Provide section parameter
to bfd_octets_per_byte.
* coff-i386.c (coff_i386_reloc): likewise.
* coff-mips.c (mips_reflo_reloc): likewise.
* coff-x86_64.c (coff_amd64_reloc): likewise.
* cofflink.c (_bfd_coff_link_input_bfd): likewise.
(_bfd_coff_reloc_link_order): likewise.
* elf.c (_bfd_elf_section_offset): likewise.
(_bfd_elf_make_section_from_shdr): likewise.
Set SEC_ELF_OCTETS for sections with names .gnu.build.attributes,
.debug*, .zdebug* and .note.gnu*.
* elf32-msp430.c (rl78_sym_diff_handler): Provide section parameter
to bfd_octets_per_byte.
* elf32-nds.c (nds32_elf_get_relocated_section_contents): likewise.
* elf32-ppc.c (ppc_elf_addr16_ha_reloc): likewise.
* elf32-pru.c (pru_elf32_do_ldi32_relocate): likewise.
* elf32-s12z.c (opru18_reloc): likewise.
* elf32-sh.c (sh_elf_reloc): likewise.
* elf32-spu.c (spu_elf_rel9): likewise.
* elf32-xtensa.c (bfd_elf_xtensa_reloc): likewise
* elf64-ppc.c (ppc64_elf_brtaken_reloc): likewise.
(ppc64_elf_addr16_ha_reloc): likewise.
(ppc64_elf_toc64_reloc): likewise.
* elflink.c (bfd_elf_final_link): likewise.
(bfd_elf_perform_complex_relocation): likewise.
(elf_fixup_link_order): likewise.
(elf_link_input_bfd): likewise.
(elf_link_sort_relocs): likewise.
(elf_reloc_link_order): likewise.
(resolve_section): likewise.
* linker.c (_bfd_generic_reloc_link_order): likewise.
(bfd_generic_define_common_symbol): likewise.
(default_data_link_order): likewise.
(default_indirect_link_order): likewise.
* srec.c (srec_set_section_contents): likewise.
(srec_write_section): likewise.
* syms.c (_bfd_stab_section_find_nearest_line): likewise.
* reloc.c (_bfd_final_link_relocate): likewise.
(bfd_generic_get_relocated_section_contents): likewise.
(bfd_install_relocation): likewise.
For section which have SEC_ELF_OCTETS set, multiply output_base
and output_offset with bfd_octets_per_byte.
(bfd_perform_relocation): likewise.
include/
* coff/ti.h (GET_SCNHDR_SIZE, PUT_SCNHDR_SIZE, GET_SCN_SCNLEN),
(PUT_SCN_SCNLEN): Adjust bfd_octets_per_byte calls.
binutils/
* objdump.c (disassemble_data): Provide section parameter to
bfd_octets_per_byte.
(dump_section): likewise
(dump_section_header): likewise. Show SEC_ELF_OCTETS flag if set.
gas/
* as.h: Define SEC_OCTETS as SEC_ELF_OCTETS if OBJ_ELF.
* dwarf2dbg.c: (dwarf2_finish): Set section flag SEC_OCTETS for
.debug_line, .debug_info, .debug_abbrev, .debug_aranges, .debug_str
and .debug_ranges sections.
* write.c (maybe_generate_build_notes): Set section flag
SEC_OCTETS for .gnu.build.attributes section.
* frags.c (frag_now_fix): Don't divide by OCTETS_PER_BYTE if
SEC_OCTETS is set.
* symbols.c (resolve_symbol_value): Likewise.
ld/
* ldexp.c (fold_name): Provide section parameter to
bfd_octets_per_byte.
* ldlang (init_opb): New argument s. Set opb_shift to 0 if
SEC_ELF_OCTETS for the current section is set.
(print_input_section): Pass current section to init_opb.
(print_data_statement,print_reloc_statement,
print_padding_statement): Likewise.
(lang_check_section_addresses): Call init_opb for each
section.
(lang_size_sections_1,lang_size_sections_1,
lang_do_assignments_1): Likewise.
(lang_process): Pass NULL to init_opb.
This patch renames elf_backend_modify_program_headers and moves the
elf.c code tweaking the ELF file header for -pie -Ttext-segment to a
new function, _bfd_elf_modify_headers, which then becomes the default
elf_backed_modify_headers and is called from any other target
elf_backed_modify_headers.
* elf-bfd.h (struct elf_backend_data <elf_backend_modify_headers>):
Rename from elf_backend_modify_program_headers.
(_bfd_elf_modify_headers): Declare.
* elf.c (assign_file_positions_except_relocs): Set
elf_program_header_size. Always call elf_backend_modify_headers.
Extract code modifying file header..
(_bfd_elf_modify_headers): ..to here. New function.
* elf32-arm.c (elf_backend_modify_headers): Renamed from
elf_backend_modify_program_headers.
* elf32-i386.c: Similarly.
* elf64-x86-64.c: Similarly.
* elfxx-target.h: Similarly. Default elf_backend_modify_headers
to _bfd_elf_modify_headers.
* elf-nacl.h (nacl_modify_headers): Rename from
nacl_modify_program_headers.
* elf-nacl.c (nacl_modify_headers): Rename from
nacl_modify_program_headers and call _bfd_elf_modify_headers.
* elf32-rx.c (elf32_rx_modify_headers): Similarly.
* elf32-spu.c (spu_elf_modify_headers): Similarly.
* elfnn-ia64.c (elfNN_ia64_modify_headers): Similarly.
* elf32-sh.c (elf_backend_modify_program_headers): Don't undef.
This patch introduces a new "sorry, cannot handle this file" bfd error
status. The idea is to use this error in cases where bfd hasn't found
a bfd_bad_value error, ie. an input file or set of options that are
invalid, but rather an input file that is simply too difficult to
process. Typically this might happen with fuzzed object files such as
the one in the PR, a wildly improbable core file. Some things are
just not worth wasting time over to fix "properly".
PR 25196
* bfd.c (bfd_error_type): Add bfd_error_sorry.
(bfd_errmsgs): Likewise.
* elf.c (rewrite_elf_program_header): Don't abort on confused
lma/alignment. Replace bfd_error_bad_value with bfd_error_sorry.
(_bfd_elf_validate_reloc): Use bfd_error_sorry.
(_bfd_elf_final_write_processing): Likewise.
* bfd-in2.h: Regenerate.
* elf-bfd.h (elf_backend_data) <elf_backend_core_find_build_id>:
New field.
(_bfd_elf32_core_find_build_id, _bfd_elf64_core_find_build_id):
New functions.
(elf_read_notes): Add declaration.
* elf.c (elf_read_notes): Move elf-bfd.h.
(_bfd_elf_core_find_build_id): New function.
(bfd_section_from_phdr): Scan core file PT_LOAD segments for
build-id if none is known.
(elf_parse_notes): For core files, scan for notes.
* elfcore.h (elf_core_file_matches_executable_p): If both
BFDs have identical build-ids, then they match.
(_bfd_elf_core_find_build_id): New function.
* elfxx-target.h (elf_backend_core_find_build_id): Define.
(elfNN_bed): Add elf_backend_core_find_build_id.
This rewrites much of assign_file_positions_for_non_load_sections to
allow objcopy and strip to handle cases like that in PR4499 where
program headers were not in their usual position immediately after the
ELF file header, and PT_LOAD headers were not sorted by paddr.
PR 4499
include/
* elf/internal.h (struct elf_segment_map): Delete header_size.
Add no_sort_lma and idx.
bfd/
* elf-nacl.c (nacl_modify_segment_map): Set no_sort_lma for all
PT_LOAD segments.
* elf32-spu.c (spu_elf_modify_segment_map): Likewise on overlay
PT_LOAD segments.
* elf.c (elf_sort_segments): New function.
(assign_file_positions_except_relocs): Use shortcuts to elfheader
and elf_tdata. Seek to e_phoff not sizeof_ehdr to write program
headers. Move PT_PHDR check..
(assign_file_positions_for_non_load_sections): ..and code setting
PT_PHDR p_vaddr and p_paddr, and code setting __ehdr_start value..
(assign_file_positions_for_load_sections): ..to here. Sort
PT_LOAD headers. Delete header_pad code. Use actual number of
headers rather than allocated in calculating size for program
headers. Don't assume program headers follow ELF file header.
Simplify pt_load_count code. Only set "off" for PT_LOAD or
PT_NOTE in cores.
(rewrite_elf_program_header): Set p_vaddr_offset for segments
that include file and program headers.
(copy_elf_program_header): Likewise, replacing header_size code.
elf_sort_sections tried to ensure a stable qsort by using target_index
as the final comparison, but target_index hasn't been set by anything
at the time elf_sort_sections was run. This patch arrange to have
target_index set.
* elf.c (_bfd_elf_map_sections_to_segments): Init target_index
for sections about to be sorted.
(assign_file_positions_for_load_sections): Likewise.
(elf_sort_sections): Don't bother optimising both TOEND case.
* elflink.c (bfd_elf_final_link): Reset target_index.
This is quite complicated because the CTF section's contents depend on
the final contents of the symtab and strtab, because it has two sections
whose contents are shuffled to be in 1:1 correspondence with the symtab,
and an internal strtab that gets deduplicated against the ELF strtab
(with offsets adjusted to point into the ELF strtab instead). It is
also compressed if large enough, so its size depends on its contents!
So we cannot construct it as early as most sections: we cannot even
*begin* construction until after the symtab and strtab are finalized.
Thankfully there is already one section treated similarly: compressed
debugging sections: the only differences are that compressed debugging
sections have extra handling to deal with their changing name if
compressed (CTF sections are always called ".ctf" for now, though we
have reserved ".ctf.*" against future use), and that compressed
debugging sections have previously-uncompressed content which has to be
stashed away for later compression, while CTF sections have no content
at all until we generate it (very late).
BFD also cannot do the link itself: libctf knows how to do it, and BFD
cannot call libctf directly because libctf already depends on bfd for
file I/O. So we have to use a pair of callbacks, one, examine_strtab,
which allows a caller to examine the symtab and strtab after
finalization (called from elf_link_swap_symbols_out(), right before the
symtabs are written, and after the strtab has been finalized), and one
which actually does the emission (called emit_ctf simply because it is
grouped with a bunch of section-specific late-emission function calls at
the bottom of bfd_elf_final_link, and a section-specific name seems best
for that). emit_ctf is actually called *twice*: once from lang_process
if the emulation suggests that this bfd target does not examine the
symtab or strtab, and once via a bfd callback if it does. (This means
that non-ELF targets still get CTF emitted, even though the late CTF
emission stage is never called for them).
v2: merged with non-ELF support patch: slight commit message
adjustments.
v3: do not spend time merging CTF, or crash, if the CTF section is
explicitly discarded. Do not try to merge or compress CTF unless
linking.
v4: add CTF_COMPRESSION_THRESHOLD. Annul the freed input ctf_file_t's
after writeout: set SEC_IN_MEMORY on the output contents so a future
bfd enhancement knows it could free it. Add SEC_LINKER_CREATED |
SEC_KEEP to avoid having to add .ctf to the linker script. Drop
now-unnecessary ldlang.h-level elf-bfd.h include and hackery around
it. Adapt to elf32.em->elf.em and elf-generic.em->ldelf*.c
changes.
v5: fix tabdamage. Drop #inclusions in .h files: include in .c files,
.em files, and use struct forwards instead. Use bfd_section_is_ctf
inline function rather than SECTION_IS_CTF macro. Move a few
comments.
* Makefile.def (dependencies): all-ld depends on all-libctf.
* Makefile.in: Regenerated.
include/
* bfdlink.h (elf_strtab_hash): New forward.
(elf_sym_strtab): Likewise.
(struct bfd_link_callbacks <examine_strtab>): New.
(struct bfd_link_callbacks <emit_ctf>): Likewise.
bfd/
* elf-bfd.h (bfd_section_is_ctf): New inline function.
* elf.c (special_sections_c): Add ".ctf".
(assign_file_positions_for_non_load_sections): Note that
compressed debugging sections etc are not assigned here. Treat
CTF sections like SEC_ELF_COMPRESS sections when is_linker_output:
sh_offset -1.
(assign_file_positions_except_relocs): Likewise.
(find_section_in_list): Note that debugging and CTF sections, as
well as reloc sections, are assigned later.
(_bfd_elf_assign_file_positions_for_non_load): CTF sections get
their size and contents updated.
(_bfd_elf_set_section_contents): Skip CTF sections: unlike
compressed sections, they have no uncompressed content to copy at
this stage.
* elflink.c (elf_link_swap_symbols_out): Call the examine_strtab
callback right before the strtab is written out.
(bfd_elf_final_link): Don't cache the section contents of CTF
sections: they are not populated yet. Call the emit_ctf callback
right at the end, after all the symbols and strings are flushed
out.
ld/
* ldlang.h: (struct lang_input_statement_struct): Add the_ctf.
(struct elf_sym_strtab): Add forward.
(struct elf_strtab_hash): Likewise.
(ldlang_ctf_apply_strsym): Declare.
(ldlang_write_ctf_late): Likewise.
* ldemul.h (ldemul_emit_ctf_early): New.
(ldemul_examine_strtab_for_ctf): Likewise.
(ld_emulation_xfer_type) <emit_ctf_early>: Likewise.
(ld_emulation_xfer_type) <examine_strtab_for_ctf>: Likewise.
* ldemul.c (ldemul_emit_ctf_early): New.
(ldemul_examine_strtab_for_ctf): Likewise.
* ldlang.c: Include ctf-api.h.
(CTF_COMPRESSION_THRESHOLD): New.
(ctf_output): New. Initialized in...
(ldlang_open_ctf): ... this new function. Open all the CTF
sections in the input files: mark them non-loaded and empty
so as not to copy their contents to the output, but linker-created
so the section gets created in the target.
(ldlang_merge_ctf): New, merge types via ctf_link_add_ctf and
ctf_link.
(ldlang_ctf_apply_strsym): New, an examine_strtab callback: wrap
ldemul_examine_strtab_for_ctf.
(lang_write_ctf): New, write out the CTF section.
(ldlang_write_ctf_late): New, late call via bfd's emit_ctf hook.
(lang_process): Call ldlang_open_ctf, ldlang_merge_ctf, and
lang_write_ctf.
* ldmain.c (link_callbacks): Add ldlang_ctf_apply_strsym,
ldlang_write_ctf_late.
* emultempl/aix.em: Add ctf-api.h.
* emultempl/armcoff.em: Likewise.
* emultempl/beos.em: Likewise.
* emultempl/elf.em: Likewise.
* emultempl/generic.em: Likewise.
* emultempl/linux.em: Likewise.
* emultempl/msp430.em: Likewise.
* emultempl/pe.em: Likewise.
* emultempl/pep.em: Likewise.
* emultempl/ticoff.em: Likewise.
* emultempl/vanilla.em: Likewise.
* ldcref.c: Likewise.
* ldctor.c: Likewise.
* ldelf.c: Likewise.
* ldelfgen.c: Likewise.
* ldemul.c: Likewise.
* ldexp.c: Likewise.
* ldfile.c: Likewise.
* ldgram.c: Likewise.
* ldlex.l: Likewise.
* ldmain.c: Likewise.
* ldmisc.c: Likewise.
* ldver.c: Likewise.
* ldwrite.c: Likewise.
* lexsup.c: Likewise.
* mri.c: Likewise.
* pe-dll.c: Likewise.
* plugin.c: Likewise.
* ldelfgen.c (ldelf_emit_ctf_early): New.
(ldelf_examine_strtab_for_ctf): tell libctf about the symtab and
strtab.
(struct ctf_strsym_iter_cb_arg): New, state to do so.
(ldelf_ctf_strtab_iter_cb): New: tell libctf about
each string in the strtab in turn.
(ldelf_ctf_symbols_iter_cb): New, tell libctf
about each symbol in the symtab in turn.
* ldelfgen.h (struct elf_sym_strtab): Add forward.
(struct elf_strtab_hash): Likewise.
(struct ctf_file): Likewise.
(ldelf_emit_ctf_early): Declare.
(ldelf_examine_strtab_for_ctf): Likewise.
* emultempl/elf-generic.em (LDEMUL_EMIT_CTF_EARLY): Set it.
(LDEMUL_EXAMINE_STRTAB_FOR_CTF): Likewise.
* emultempl/aix.em (ld_${EMULATION_NAME}_emulation): Add
emit_ctf_early and examine_strtab_for_ctf, NULL by default.
* emultempl/armcoff.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/beos.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/elf.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/generic.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/linux.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/msp430.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/pe.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/pep.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/ticoff.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/vanilla.em (ld_vanilla_emulation): Likewise.
* Makefile.am: Pull in libctf (and zlib, a transitive requirement
for compressed CTF section emission). Pass it on to DejaGNU.
* configure.ac: Add AM_ZLIB.
* aclocal.m4: Added zlib.m4.
* Makefile.in: Regenerated.
* testsuite/ld-bootstrap/bootstrap.exp: Use it when relinking ld.
The code in ctf_bfdopen_ctfsect (which is the ultimate place where you
end up if you use ctf_open to open a CTF file and pull in the ELF string
and symbol tables) was written before it was possible to actually test
it, since the linker was not written. Now it is, it turns out that the
previous code was completely nonfunctional: it assumed that you could
load the symbol table via bfd_section_from_elf_index (...,elf_onesymtab())
and the string table via bfd_section_from_elf_index on the sh_link.
Unfortunately BFD loads neither of these sections in the conventional
fashion it uses for most others: the symbol table is immediately
converted into internal form (which is useless for our purposes, since
we also have to work in the absence of BFD for readelf, etc) and the
string table is loaded specially via bfd_elf_get_str_section which is
private to bfd/elf.c.
So make this function public, export it in elf-bfd.h, and use it from
libctf, which does something similar to what bfd_elf_sym_name and
bfd_elf_string_from_elf_section do. Similarly, load the symbol table
manually using bfd_elf_get_elf_syms and throw away the internal form
it generates for us (we never use it).
BFD allocates the strtab for us via bfd_alloc, so we can leave BFD to
deallocate it: we allocate the symbol table ourselves before calling
bfd_elf_get_elf_syms, so we still have to free it.
Also change the rules around what you are allowed to provide: It is
useful to provide a string section but no symbol table, because CTF
sections can legitimately have no function info or data object sections
while relying on the ELF strtab for some of their strings. So allow
that combination.
v4: adjust to upstream changes. ctf_bfdopen_ctfsect's first parameter
is potentially unused again (if BFD is not in use for this link
due to not supporting an ELF target).
v5: fix tabdamage.
bfd/
* elf-bfd.h (bfd_elf_get_str_section): Add.
* elf.c (bfd_elf_get_str_section): No longer static.
libctf/
* ctf-open-bfd.c: Add <assert.h>.
(ctf_bfdopen_ctfsect): Open string and symbol tables using
techniques borrowed from bfd_elf_sym_name.
(ctf_new_archive_internal): Improve comment.
* ctf-archive.c (ctf_arc_close): Do not free the ctfi_strsect.
* ctf-open.c (ctf_bufopen): Allow opening with a string section but
no symbol section, but not vice versa.
PR 24456
* elf.c (bfd_section_from_shdr): Issue an informative warning
message and continue processing other sections after encountering
a reloc section for a section which already has other relocs
associated with it.
This parameter might appear to be used to set up offset_size, but
since git commit 024b2372f5 offset_size is either set from the
debug_info data or is set to 4.
* dwarf2.c (_bfd_dwarf2_find_nearest_line): Remove addr_size parameter.
* libbfd-in.h (_bfd_dwarf2_find_nearest_line): Update prototype.
* coffgen.c (coff_find_nearest_line_with_names): Adjust
_bfd_dwarf2_find_nearest_line calls.
* elf.c (_bfd_elf_find_nearest_line, _bfd_elf_find_line): Likewise.
* elf32-arm.c (elf32_arm_find_nearest_line): Likewise.
* elf64-alpha.c (elf64_alpha_find_nearest_line): Likewise.
* elfnn-aarch64.c (elfNN_aarch64_find_nearest_line): Likewise.
* elfxx-mips.c (_bfd_mips_elf_find_nearest_line): Likewise.
* mach-o.c (bfd_mach_o_find_nearest_line): Likewise.
* libbfd.h: Regenerate.
When SHF_GNU_MBIND was added in the SHF_LOOS to SHF_HIOS range, it
should have required ELFOSABI_GNU since these flags are already in use
by other OSes. HPUX SHF_HP_TLS in fact has the same value. That
means no place in binutils should test SHF_GNU_MBIND without first
checking OSABI, and SHF_GNU_MBIND should not be set without also
setting OSABI. At least, that's the ideal, but the patch accepts
SHF_GNU_MBIND on ELFOSABI_NONE object files since gas didn't always
set OSABI. However, to reinforce the fact that SHF_GNU_MBIND isn't
proper without a non-zero OSABI, readelf will display the flag as
LOOS+0 if OSABI isn't set.
The clash with SHF_HP_TLS means that hppa64-linux either has that flag
on .tbss sections or supports GNU_MBIND, not both. (hppa64-linux
users, if there are any, may have noticed that GNU ld since 2017
mysteriously aligned their .tbss sections to a 4k boundary. That was
one consequence of SHF_HP_TLS being blindly interpreted as
SHF_GNU_MBIND.) Since it seems that binutils, gdb, gcc, glibc, and
the linux kernel don't care about SHF_HP_TLS I took that flag out of
.tbss for hppa64-linux.
bfd/
* elf-bfd.h (enum elf_gnu_osabi): Add elf_gnu_osabi_mbind.
* elf.c (_bfd_elf_make_section_from_shdr): Set elf_gnu_osabi_mbind.
(get_program_header_size): Formatting. Only test SH_GNU_MBIND
when elf_gnu_osabi_mbind is set.
(_bfd_elf_map_sections_to_segments): Likewise.
(_bfd_elf_init_private_section_data): Likewise.
(_bfd_elf_final_write_processing): Update comment.
* elf64-hppa.c (elf64_hppa_special_sections): Move .tbss entry.
(elf_backend_special_sections): Define without .tbss for linux.
binutils/
* readelf.c (get_parisc_segment_type): Split off hpux entries..
(get_ia64_segment_type): ..and these..
(get_hpux_segment_type): ..to here.
(get_segment_type): Condition GNU_MBIND on osabi. Use
get_hpux_segment_type.
(get_symbol_binding): Do not print UNIQUE for ELFOSABI_NONE.
(get_symbol_type): Do not print IFUNC for ELFOSABI_NONE.
gas/
* config/obj-elf.c (obj_elf_change_section): Don't emit a fatal
error for non-SHF_ALLOC SHF_GNU_MBIND here.
(obj_elf_parse_section_letters): Return SHF_GNU_MBIND in new
gnu_attr param.
(obj_elf_section): Adjust obj_elf_parse_section_letters call.
Formatting. Set SHF_GNU_MBIND and elf_osabi from gnu_attr.
Emit normal error for non-SHF_ALLOC SHF_GNU_MBIND and wrong osabi.
(obj_elf_type): Set elf_osabi for ifunc.
* testsuite/gas/elf/section12a.d: xfail msp430 and hpux.
* testsuite/gas/elf/section12b.d: Likewise.
* testsuite/gas/elf/section13.d: Likewise.
* testsuite/gas/elf/section13.l: Adjust expected error.
ld/
* emultempl/elf32.em (gld${EMULATION_NAME}_place_orphan): Condition
SHF_GNU_MBIND on osabi. Set output elf_gnu_osabi_mbind.
PR 24717
* elf.c (is_debuginfo_file): New function.
(assign_file_positions_for_non_load_sections): Do not warn about
allocated sections outside of loadable segments if they are found
in a debuginfo file.
* elf-bfd.h (is_debuginfo_file): Prototype.
PR 24708
* elf.c (_bfd_elf_slurp_version_tables): Check for an excessively
large version reference section.
* compress.c (bfd_get_full_section_contents): Check for an
uncompressed section whose size is larger than the file size.
PR 24650
* elf.c (elfcore_make_auxv_note_section): New function.
(elfcore_grok_note): Use it.
(elfcore_grok_freebsd_note): Likewise.
(elfcore_grok_openbsd_note): Likewise.
(elfcore_grok_netbsd_note): Likewise. Plus add support for
NT_NETBSDCORE_AUXV notes.
After fixing the ld-elf/pr22836-1a segmentation fault we run into an
assertion failure due to the generic ELF target not removing empty
SHT_GROUP sections. Avoid that.
* elf.c (bfd_elf_set_group_contents): Exit on zero size section.
Reverts commit 1ff31e135f, fixing the problem more generally. There
are likely other place that will segfault on a NULL section.
PR 24337
* elf.c (_bfd_elf_rela_local_sym): Revert last change.
(_bfd_elf_rel_local_sym): Likewise.
* elflink.c (elf_link_input_bfd): Use bfd_und_section for
section of symbols with unrecognized shndx.
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.
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.
Commit 2bf2bf23da exposed a bug on targets that create common sections
other than the standard ELF SHN_COMMON. If these are output by ld -r,
then their type becomes SHT_PROGBITS unless the target handles them
specially (eg. by elf_backend_special_sections), and if they are
merged into .bss/.sbss by ld -r then that section becomes SHT_PROGBITS.
Worse, if they are output by ld -r, then their size is increased by
bfd_generic_define_common_symbol during final link, which leads to
bogus file contents being copied to output.
For mips, it seems to me that the .scommon section should not be
output for ld -r, but I haven't made that change in this patch.
PR 24015
* elf.c (bfd_elf_get_default_section_type): Make common sections
SHT_NOBITS.
* linker.c (bfd_generic_define_common_symbol): Clear
SEC_HAS_CONTENTS.
PR 23994
* aoutx.h: Include limits.h.
(get_reloc_upper_bound): Detect long overflow and return a file
too big error if it occurs.
* elf.c: Include limits.h.
(_bfd_elf_get_symtab_upper_bound): Detect long overflow and return
a file too big error if it occurs.
(_bfd_elf_get_dynamic_symtab_upper_bound): Likewise.
(_bfd_elf_get_dynamic_reloc_upper_bound): Likewise.
Linkers group input note sections with the same name into one output
note section with the same name. One output note section is placed in
one PT_NOTE segment. New linkers merge all input .note.gnu.property
sections into one output .note.gnu.property section with a single
NT_GNU_PROPERTY_TYPE_0 note in a single PT_NOTE segment. Since older
linkers treat input .note.gnu.property section as a generic note section
and just concatenate all input .note.gnu.property sections into one
output .note.gnu.property section without merging them, we may
see one or more NT_GNU_PROPERTY_TYPE_0 notes in PT_NOTE segment, which
are invalid.
GNU_PROPERTY_X86_UINT32_VALID was defined to address this issue such
that linker sets the bit for non-relocatable outputs. But it isn't
sufficient:
1. It doesn't cover generic properties.
2. When -mx86-used-note=yes is passed to x86 assembler, the
GNU_PROPERTY_X86_UINT32_VALID bit is set in GNU_PROPERTY_X86_ISA_1_USED
property in object file and older linkers generate invalid
NT_GNU_PROPERTY_TYPE_0 notes with the GNU_PROPERTY_X86_UINT32_VALID bit
set.
I am proposing the following changes:
1. Add PT_GNU_PROPERTY segment type:
# define PT_GNU_PROPERTY (PT_LOOS + 0x474e553)
which covers .note.gnu.property section.
2. Remove GNU_PROPERTY_X86_UINT32_VALID.
bfd/
PR ld/23900
* elf.c (get_program_header_size): Add a PT_GNU_PROPERTY
segment for NOTE_GNU_PROPERTY_SECTION_NAME.
(_bfd_elf_map_sections_to_segments): Create a PT_GNU_PROPERTY
segment for NOTE_GNU_PROPERTY_SECTION_NAME.
* elfxx-x86.c (_bfd_elf_link_setup_gnu_properties): Don't set
GNU_PROPERTY_X86_UINT32_VALID.
binutils/
PR ld/23900
* readelf.c (get_segment_type): Support PT_GNU_PROPERTY.
(decode_x86_isa): Don't check GNU_PROPERTY_X86_UINT32_VALID.
(decode_x86_feature_1): Likewise.
(decode_x86_feature_2): Likewise.
(print_gnu_property_note): Remove GNU_PROPERTY_X86_UINT32_VALID
check.
* testsuite/binutils-all/i386/empty.d: Updated.
* testsuite/binutils-all/x86-64/empty-x32.d: Likewise.
* testsuite/binutils-all/x86-64/empty.d: Likewise.
* testsuite/binutils-all/i386/pr21231b.s: Change
GNU_PROPERTY_X86_ISA_1_USED bits to 0x7fffffff.
* testsuite/binutils-all/x86-64/pr21231b.s: Likewise.
gas/
PR ld/23900
* config/tc-i386.c (x86_cleanup): Don't set
GNU_PROPERTY_X86_UINT32_VALID.
* testsuite/gas/i386/property-1.s: Change
GNU_PROPERTY_X86_ISA_1_USED bits to 0.
include/
PR ld/23900
* elf/common.h (PT_GNU_PROPERTY): New.
(GNU_PROPERTY_X86_UINT32_VALID): Removed.
ld/
PR ld/23900
* testsuite/ld-elf/elf.exp: Run PR ld/23900 test.
* testsuite/ld-elf/pr23900-1-32.rd: New file.
* testsuite/ld-elf/pr23900-1-64.rd: Likewise.
* testsuite/ld-elf/pr23900-1.d: Likewise.
* testsuite/ld-elf/pr23900-1.s: Likewise.
* testsuite/ld-elf/pr23900-2.s: Likewise.
* testsuite/ld-elf/pr23900-2a.d: Likewise.
* testsuite/ld-elf/pr23900-2b.d: Likewise.
* testsuite/ld-i386/ibt-plt-1.d: Adjusted.
* testsuite/ld-i386/ibt-plt-2c.d: Likewise.
* testsuite/ld-i386/ibt-plt-2d.d: Likewise.
* testsuite/ld-i386/ibt-plt-3d.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-1-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-1.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2c-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2c.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2d-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2c.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3c-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3c.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3d-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3d.d: Likewise.
* testsuite/ld-i386/pr23372c.d: Expect <None>
for GNU_PROPERTY_X86_ISA_1_USED.
* testsuite/ld-x86-64/pr23372c-x32.d: Likewise.
* testsuite/ld-x86-64/pr23372c.d: Likewise.
* testsuite/ld-x86-64/pr23372d-x32.d: Likewise.
* testsuite/ld-x86-64/pr23372d.d: Likewise.
* testsuite/ld-x86-64/property-x86-5a.s: Change
GNU_PROPERTY_X86_ISA_1_USED bits to 0.
* testsuite/ld-x86-64/property-x86-5b.s: Likewise.
PR 23932
* elf.c (IS_CONTAINED_BY_LMA): Add a check for a negative section
size.
(rewrite_elf_program_header): If no sections are mapped into a
segment return an error.
PR binutils/23919
binutils* readelf.c (dump_sections_as_strings): Remove bogus addralign check.
(dump_sections_as_bytes): Likewise.
(load_specific_debug_sections): Likewise.
* testsuite/binutils-all/dw2-3.rS: Adjust alignment.
* testsuite/binutils-all/dw2-3.rt: Likewise.
bfd * bfd.c (bfd_update_compression_header): Explicitly set alignment.
(bfd_check_compression_header): Add uncompressed_alignment_power
argument. Check ch_addralign is a power of 2.
* bfd-in2.h: Regenerated.
* compress.c (bfd_compress_section_contents): Get and set
orig_uncompressed_alignment_pow if section is decompressed.
(bfd_is_section_compressed_with_header): Add and get
uncompressed_align_pow_p argument.
(bfd_is_section_compressed): Add uncompressed_align_power argument
to bfd_is_section_compressed_with_header call.
(bfd_init_section_decompress_status): Get and set
uncompressed_alignment_power.
* elf.c (_bfd_elf_make_section_from_shdr): Add
uncompressed_align_power argument to
bfd_is_section_compressed_with_header call.
strip/objcopy can't deal with alloc reloc sections, not .rela.dyn or
.rela.plt in a dynamic executable, or .rela.plt/.rela.iplt in a static
executable. So, don't have BFD treat them as side-channel data
associated with the section they are relocating.
PR 23850
* elf.c (bfd_section_from_shdr): Treat SHF_ALLOC SHT_REL* sections
in an executable or shared library as normal sections.
Symbol tables can change when a number of objcopy options are used.
I figure string tables are similarly changeable.
PR 23788
* elf.c (section_match): Don't require a size match for SHT_SYMTAB
or SHT_STRTAB.
This patch, along with previous patches in the series, supports
putting the ELF file header and program headers in a PT_LOAD without
sections.
Logic governing whether headers a loaded has changed a little: The
primary reason to include headers is now the presence of
SIZEOF_HEADERS in a linker script. However, to support scripts that
may have reserved space for headers by hand, we continue to add
headers whenever the first section address is past the end of headers
modulo page size.
include/
* bfdlink.h (struct bfd_link_info): Add load_phdrs field.
bfd/
* elf-nacl.c (nacl_modify_segment_map): Cope with header PT_LOAD
lacking sections.
* elf.c (_bfd_elf_map_sections_to_segments): Assume file and
program headers are required when info->load_phdrs. Reorganize
code handling program headers. Generate a mapping without
sections just for file and program headers when -z separate-code
would indicate they should be on a different page to the first
section.
ld/
* ldexp.c (fold_name <SIZEOF_HEADERS>): Set link_info.load_phdrs.
* testsuite/ld-elf/loadaddr1.d: Pass -z noseparate-code.
* testsuite/ld-elf/loadaddr2.d: Likewise.
* testsuite/ld-i386/vxworks2.sd: Adjust expected output.
* testsuite/ld-powerpc/vxworks2.sd: Likewise.
* testsuite/ld-elf/overlay.d: Remove spu xfail.
* testsuite/ld-spu/ovl.lnk: Don't use SIZEOF_HEADERS.
* testsuite/ld-tic6x/dsbt-be.ld: Likewise.
* testsuite/ld-tic6x/dsbt-inrange.ld: Likewise.
* testsuite/ld-tic6x/dsbt-overflow.ld: Likewise.
* testsuite/ld-tic6x/dsbt.ld: Likewise.
p_vaddr is currently set from the first section vma if a segment has
sections, and to zero if a segment has no sections. This means we
lose p_vaddr when objcopy'ing executables if a segment without
sections has a non-zero p_vaddr.
This patch saves p_vaddr to p_vaddr_offset, and to make the use of
p_vaddr_offset consistent, inverts the sign. (It's now added to
section vma to get segment vaddr, and added to zero when there are no
sections.)
* elf.c (assign_file_positions_for_load_sections): Set p_vaddr
from m->p_vaddr_offset for segments without sections. Invert
sign of p_vaddr_offset.
(rewrite_elf_program_header, copy_elf_program_header): Save
old segment p_vaddr to p_vaddr_offset. Invert sign of
p_vaddr_offset.
Some targets don't set a default interpreter, resulting in an empty
.interp section unless --dynamic-linker is passed to ld. A PT_INTERP
without a path is rather useless.
The testsuite change fixes a failure on microblaze-linux.
bfd/
* elf.c (get_program_header_size): Don't count PT_INTERP if
.interp is empty.
(_bfd_elf_map_sections_to_segments): Don't create PT_INTERP if
.interp is empty.
ld/
* testsuite/ld-elf/pr22423.d: Pass --dynamic-linker to ld.
This cleans up elf_segment_map allocation when the section array is
empty. "amt += (to - from - 1) * sizeof (asection *)", when "to" and
"from" are unsigned int results in an unsigned value inside the
parentheses. When "to" and "from" are equal on a 64-bit host,
0xffffffff * 8 is added to "amt", not -8 as desired.
The patch also renames a variable for consistency with other functions
using a similar index.
* elf.c (make_mapping): Cope with zero size array at end of
struct elf_segment_map.
(_bfd_elf_map_sections_to_segments): Likewise.
(rewrite_elf_program_header, copy_elf_program_header): Likewise.
(_bfd_elf_map_sections_to_segments): Rename phdr_index to hdr_index.
Alignments of SHT_NOTE sections can be 8 bytes for 64-bit ELF files. We
should put all adjacent SHT_NOTE sections with the same section alignment
into a single PT_NOTE segment even when the section alignment != 4 bytes.
Also check SHT_NOTE section type instead of section name.
PR ld/23658
* elf.c (get_program_header_size): Put all adjacent SHT_NOTE
sections with the same section alignment into a single PT_NOTE
segment. Check SHT_NOTE section type instead of section name.
(_bfd_elf_map_sections_to_segments): Likewise.
When opening a BFD for update, as gdb --write does, modifications to
anything but the contents of sections is restricted.
Do not try to write back any ELF headers in this case.
bfd/ChangeLog
2018-09-24 Jozef Lawrynowicz <jozef.l@mittosystems.com>
PR gdb/20948
* elf.c (_bfd_elf_write_object_contents): Return from function
early if abfd->direction == both_direction.
gdb/testsuite/ChangeLog
2018-09-24 Jozef Lawrynowicz <jozef.l@mittosystems.com>
PR gdb/20948
* gdb.base/write_mem.exp: New test.
* gdb.base/write_mem.c: Likewise.
VMA of the first section in the segment containing the ELF file header
(and possibly section headers too) can't be used to reliably find the
size of the headers plus padding. What's really needed is sh_offset
of the first section assuming it has contents (vma does have a
relationship to sh_offset, but is only guaranteed in demand paged
executables).
If the first section is SHT_NOBITS and it hasn't been converted to
have file contents by the existence of a following SHT_PROGBITS
section in the same segment, the sh_offset value also isn't reliable.
PR 23595
elf.c (copy_elf_program_header): When first segment contains
only the headers and SHT_NOBITS sections, use segment p_filesz
to calculate header and padding size. Use filepos of the first
section otherwise.
The BFD linker with PR ld/23499 may generate shared libraries with
corrupt symbol version info which leads to linker error when the
corrupt shared library is used:
/usr/bin/ld: bin/libKF5Service.so.5.49.0: _edata: invalid version 21 (max 0)
/usr/bin/ld: bin/libKF5Service.so.5.49.0: error adding symbols: bad value
Add check for corrupt symbol version info to objdump:
00000000000af005 g D .data 0000000000000000 <corrupt> _edata
and readelf:
728: 00000000000af005 0 NOTYPE GLOBAL DEFAULT 25 _edata@<corrupt> (5)
bfd/
PR ld/23499
* elf.c (_bfd_elf_get_symbol_version_string): Return
_("<corrupt>") for corrupt symbol version info.
binutils/
PR ld/23499
* readelf.c (get_symbol_version_string): Return _("<corrupt>")
for corrupt symbol version info.
Alan Modra
Christian Eggers
Keith Seitz
Nick Alcock
Nick Clifton
Martin Liska
Christos Zoulas
Alan Hayward
H.J. Lu
Mark Wielaard
Jozef Lawrynowicz