On S/390 we see quite often registers marked as "bad register" in the
readelf --debug-dump=frames or objdump -Wf output.
00000000 0000000000000014 00000000 CIE
Version: 1
Augmentation: "zR"
Code alignment factor: 1
Data alignment factor: -8
Return address column: 14
Augmentation data: 1b
DW_CFA_def_cfa: r15 ofs 160
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
...
00000050 000000000000001c 00000054 FDE cie=00000000 pc=0000000080000e58..0000000080000e84
DW_CFA_advance_loc: 6 to 0000000080000e5e
DW_CFA_offset: r14 at cfa-48
DW_CFA_offset: r15 at cfa-40
DW_CFA_advance_loc: 6 to 0000000080000e64
DW_CFA_def_cfa_offset: 320
DW_CFA_advance_loc: 18 to 0000000080000e76
DW_CFA_restore: bad register: r15 <------
DW_CFA_restore: r14
DW_CFA_def_cfa_offset: 160
This is triggered by this check in display_debug_frames (dwarf.c):
case DW_CFA_restore:
if (opa >= (unsigned int) cie->ncols
|| opa >= (unsigned int) fc->ncols)
reg_prefix = bad_reg;
cie->ncols is number of registers referenced in the CIE which is 15 due
to r14 being given as return address column. So for the CFA_restore of
r15 a "bad register" is being printed while the same rule on r14 is ok.
The reason for this check is to prevent wild memory accesses when
reading input with corrupted register values while accessing the
col_type/col_offset arrays. However in that case r15 is a perfectly
valid register. It just happens not to be mentioned in the CIE. Hence
restoring the CIE rule for r15 should end up with the default rule which
is DW_CFA_undefined.
This probably wasn't observed on other platforms because they either do
not use CFA_restore (x86-64) or do not issue CFA_restore on registers
with a higher number than the return address column.
binutils/ChangeLog:
2016-09-29 Andreas Krebbel <krebbel@linux.vnet.ibm.com>
* dwarf.c (frame_display_row): Fix formatting of return address
register column.
(display_debug_frames): Ignore invalid indices into
cie->col_type/cie->col_offset arrays and default to
DW_CF_undefined instead.
This patch adds support for .cfi_val_offset GAS pseudo command which
maps to DW_CFA_val_offset and DW_CFA_val_offset_sf.
gas/ChangeLog:
2016-09-29 Andreas Krebbel <krebbel@linux.vnet.ibm.com>
* doc/as.texinfo: Add docu for .cfi_val_offset.
* dw2gencfi.c (cfi_add_CFA_val_offset): New function.
(dot_cfi): Add case for DW_CFA_val_offset.
(output_cfi_insn): Likewise.
(cfi_pseudo_table): Add entry for cfi_val_offset.
* dw2gencfi.h: Add prototype for cfi_add_CFA_val_offset.
* testsuite/gas/cfi/cfi-common-8.d: New test.
* testsuite/gas/cfi/cfi-common-8.s: New test.
* testsuite/gas/cfi/cfi.exp: Run cfi-common-8 testcase.
binutils/ChangeLog:
2016-09-29 Andreas Krebbel <krebbel@linux.vnet.ibm.com>
* dwarf.c (display_debug_frames): Adjust output line.
PR binutils/20440
* dwarf.c (display_debug_lines_decoded): Add checks for running
off the end of the section when populating the directory table and
file table.
(frame_display_row): Set max_regs equal to ncols.
(load_specific_debug_section): If the section is compressed, but
it is not big enough to hold a compression header then warn and
return 0.
PR 19872
bfd * dwarf2.c (parse_comp_unit): Skip warning about unrecognised
version number if the version is zero.
bin * dwarf.c (display_debug_aranges): Skip warning about unrecognised
version number if the version is zero.
When the DWARF address size is 32-bit, but the host machine is 64-bit,
objdump fails to spot base addresses specified in the .debug_ranges and
.debug_loc lists.
As an example, here is the output when dumping an example .debug_ranges
section with the pre-patched objdump:
Contents of the .debug_ranges section:
Offset Begin End
00000000 ffffffff 00000004 (start > end)
00000000 00000000 00000004
00000000 ffffffff 00000008 (start > end)
00000000 00000000 00000004
00000000 <End of list>
And this is what the same section looks like when dumped with the
patched version of objdump:
Contents of the .debug_ranges section:
Offset Begin End
00000000 ffffffff 00000004 (base address)
00000000 00000004 00000008
00000000 ffffffff 00000008 (base address)
00000000 00000008 0000000c
00000000 <End of list>
binutils/ChangeLog:
* dwarf.c (is_max_address): New function.
(display_loc_list): Remove out of date comment, use
is_max_address.
(display_debug_ranges): Likewise.
binutils/testsuite/ChangeLog:
* binutils-all/objdump.exp: Add test for .debug_ranges decode.
* binutils-all/dw2-ranges.S: New file.
* binutils-all/dw2-ranges.W: New file.
This patch fixes all occurences of left-shifting negative constants in C code
which is undefined by the C standard.
binutils/ChangeLog:
* dwarf.c (read_leb128): Fix left shift of negative value.
PR binutils/18374
bin * dwarf.h (struct dwarf_section): Add reloc_info and num_relocs
fields.
(struct dwarf_section_display): Change bitfield to boolean.
(reloc_at): Add prototype.
* dwarf.c (display_loc_list): Ignore list terminators if there are
relocs against them.
(display_debug_loc): Issue a warning if there are relocs against
the .debug_loc section.
(display_displays): Initialise reloc_info and num_relocs fields.
* objdump.c (load_specific_debug_section): Initialise reloc_info
and num_relocs fields.
(reloc_at): New function.
* readelf.c (is_32bit_abs_reloc): Add IA64's R_IA64_DIS32LSB
reloc.
(reloc_at): New function.
(apply_relocations): Add relocs_return and num_relocs_return
parameters. Fill them in with the loaded relocs if non-NULL.
(dump_section_as_bytes): Update call to apply_relocations.
(load_specific_debug_section): Initialise reloc_info and
num_relocs fields.
tests * binutils-all/pr18374.s: New test file.
* binutils-all/readelf.exp: Assemble and run the new test.
* binutils-all/readelf.pr18374: Expected output from readelf.
PR binutils/17512
* dwarf.c (display_debug_loc): Pacify the undefined behaviour
sanitizer by simplifying address difference calculation.
(struct Frame_Chunk): Change type of cfa_offset to dwarf_vma in
order to avoid arithmetic overflows.
(frame_display_row): Cast cfa_offset before printing it.
(display_debug_frames): Likewise.
Check for an unexpected segment size.
Chnage type of 'l' local to dwarf_vma and cast it back to an int
when printing.
(process_cu_tu_index): Tighten check for an invalid ncols value.
* readelf.c (process_corefile_note_segment): Check for
inote.descdata extending beyond the end of the section.
(process_v850_notes): Likewise.
PR binutils/17531
* dwarf.c (display_debug_aranges): Add check for an excessive
ar_length value.
(process_cu_tu_index): Check for a row * columns sum being too
large.
PR binutils/17531
* dwarf.c (display_debug_pubnames_worker): Work around compiler
bug checking address ranges.
(display_debug_frames): Likewise.
(display_gdb_index): Likewise.
(process_cu_tu_index): Add range check on the ncols value.
PR binutils/17531
* dwarf.c (display_debug_pubnames_worker): Use dwarf_vma type for
offset.
* readelf.c (dump_relocations): Handle printing offsets which are
MIN_INT.
(process_corefile_note_segment): Add range check of the namesz
field.
PR binutils/17531
* dwarf.c (process_debug_info): Zero the debug information array
since correct initialisation cannot be relied upon.
(process_cu_tu_index): Improve range checks.
PR binutils/17512
* dwarf.c (eh_addr_size): Use an unsigned type.
(size_of_encoded_value): Return an unsigned type.
(read_leb128): Break if the shift becomes too big.
(process_extended_line_op): Do not read the address if the length
is too long.
(read_cie): Warn and fail if the pointer size or segment size are
too big.
* dwarf.h (DWARF2_External_LineInfo): Delete unused and incorrect
structure definition.
(DWARF2_External_PubNames): Likewise.
(DWARF2_External_CompUnit): Likewise.
(DWARF2_External_ARange): Likewise.
(DWARF2_Internal_LineInfo): Use dwarf_vma type for
li_prologue_length.
(eh_addr_size): Update prototype.
* coffcode.h (styp_to_sec_flags): Use an unsigned long type to
hold the flag bits.
* peXXigen.c (pe_print_reloc): Use unsigned types to hold the
size and number of relocs.
(pe_print_debugdata): Use a 32-bit aligned buffer to store the
codeview record.
* versados.c (process_otr): Check the esdid value before using it
to access the EDATA.
DWARFv5 defines and GCC5 may output two new DW_LANG constants for the
Fortran 2003 and Fortran 2008 standards. Handle and display both in
binutils.
binutils/ChangeLog:
* dwarf.c (read_and_display_attr_value): Handle DW_LANG_Fortran03
and DW_LANG_Fortran08.
include/ChangeLog:
* dwarf2.h: Add DW_LANG_Fortran03 and DW_LANG_Fortran08.
http://dwarfstd.org/ShowIssue.php?issue=141121.1
PR binutils/17512
* dwarf.c (display_debug_frames): Fix range checks to work on
32-bit binaries complied on a 64-bit host.
* peXXigen.c (rsrc_print_resource_entries): Add range check for
addresses that wrap around the address space.
(rsrc_parse_entry): Likewise.
PR binutils/17531
* dwarf.c (read_and_display_attr_value): Test for a block length
being so long that it wraps around to before the start of the block.
(process_debug_info): Test for section_begin wrapping around to
before the start of the section.
(display_gdb_index): Test for num_cus being so large that the end
address wraps around to before the start of the section.
(process_cu_tu_index): Test for j being so large that the section
index pool wraps around to before the start of the section.
PR binutils/17531
* dwarf.c (process_debug_info): Add range check.
(display_debug_pubnames_worker): Likewise.
(display_gdb_index): Fix range check.
(process_cu_tu_index): Add range check.
* readelf.c (get_data): Change parameter types from size_t to
bfd_size_type. Add checks for loss of accuracy when casting from
bfd_size_type to size_t.
(get_dynamic_data): Likewise.
(process_section_groups): Limit number of error messages.
abbrev_base is independent of abbrev_size. We should use abbrev_base +
abbrev_size to check abbrev section size.
* dwarf.c (process_debug_info): Properly check abbrev size.
PR binutils/17531
* dwarf.c (process_debug_info): Check for abbrev_base being larger
than the section size.
(process_cu_tu_index): Use xcalloc2 to allocate the CU and TU
arrays.
(xcalloc2): New function. Like xcalloc, but checks for overflow.
* dwarf.h (xcalloc2): Prototype.
PR binutils/17531
* dwarf.c (alloc_num_debug_info_entries): New variable.
(process_debug_info): Set it. Use it to avoid displaying
attributes for which there is no info.
(display_debug_abbrev): Check that the debug_info_entry index is
valid before using it.
(display_loc_list_dwo): Likewise.
(process_cu_tu_index): Add range check for an overlarge dw_sect
value.
(free_debug_memory): Reset alloc_num_debug_info_entries.
* readelf.c (slurp_ia64_unwind_table): Warn if the reloc could not
be indentified.
(dynamic_section_mips_val): Warn if the timestamp is invalid.
(print_mips_got_entry): Add a data_end parameter. Warn if a read
would go beyond the end of the data, and return an error value.
(process_mips_specific): Do not read options from beyond the end
of the section.
Correct code to display optional data at the end of an option.
Warn if there are too many GOT symbols.
Update calls to print_mips_got_entry, and handle error returns.
PR binutils/17531
* dwarf.c (decode_location_expression): Check for an out of range
value for a DW_OP_GNU_entry_value expression.
(display_debug_lines_raw): Check for a partial
.debug_line. section being encountered without a prior, full
.debug.line section.
(display_debug_lines_decoded): Likewise. Also check for
li_line_range being zero.
(display_debug_pubnames_worker): Check for an invalid pn_length
field.
(read_cie): Add range checks.
* elfcomm.c (setup_archive): Check for a negative longnames_size.
Also fix a place where %lld was wrongly used to print a dwarf_vma.
* configure.ac: Check for long long and sizes of long long and long.
* elfcomm.h (HOST_WIDEST_INT): Test HAVE_LONG_LONG in place of
__STDC_VERSION__ and __GNUC__.
* strings.c (print_strings): Likewise.
* dwarf.c (DWARF_VMA_FMT, DWARF_VMA_FMT_LONG): Likewise.
(read_debug_line_header): Use dwarf_vmatoa to print warning.
* configure: Regenerate.
* config.in: Regenerate.
PR binutils/17531
* dwarf.c (display_debug_frames): Check for a negative
augmentation data length.
(display_gdb_index): Check for invalid offsets.
* elfcomm.c (process_archive_index_and_symbols): Check for an
index number that overflows when multiplied by the ar index size.
* readelf.c (dump_ia64_unwind): Add range checks.
(slurp_ia64_unwind_table): Change to a boolean function. Add
range checks.
(process_version_sections): Add range checks.
(get_symbol_version_string): Add check for missing section
headers.
PR binutils/17512
* dwarf.h (struct dwarf_section): Add user_data field.
* dwarf.c (frame_need_space): Check for an over large register
number.
(display_debug_frames): Check the return value from
frame_need_space. Check for a CFA expression that is so long the
start address wraps around.
(debug_displays): Initialise the user_data field.
* objdump.c (load_specific_debug_section): Save the BFD section
pointer in the user_data field of the dwarf_section structure.
(free_debug_section): Update BFD section data when freeing section
contents.
* readelf.c (load_specific_debug_section): Initialise the
user_data field.
* archive.c (do_slurp_coff_armap): Add range checks to prevent
running off the end of the string table.
* compress.c (bfd_get_full_section_contents): Return a NULL
pointer for zero sized sections. Do not attempt to copy a buffer
onto itself.
* elf-attrs.c (_bfd_elf_parse_attributes): Check for an empty
header. Add range checks to avoid running off the end of the
section.
* elf.c (bfd_elf_get_str_section): Seek before allocating so that
if the seek fails, no memory is allocated.
(bfd_elf_string_from_elf_section): Do not allocate a string from a
non string section. It only leads to trouble later on.
(_bfd_elf_print_private_bfd_data): Check for there being too
little external dynamic data.
(bfd_section_from_shdr): Replace assertion with a failure mode.
(bfd_section_from_shdr): When walking a loaded group section use
the internal structure size, not the external size. Check for the
group section being empty.
* elf32-i386.c (elf_i386_rtype_to_howto): Replace assertion with a
failure mode.
* elfcode.h (elf_slurp_reloc_table): Likewise.
* reloc.c (bfd_perform_relocation): Avoid seg-fault if the howto
parameter is NULL.
PR binutils/17531
* dwarf.c (process_cu_tu_index): Check for an out of range row
index.
* elfcomm.c (adjust_relative_path): Change name_len parameter to
an unsigned long. Check for path length overflow.
(process_archive_index_and_symbols): Check for invalid header
size.
(setup_archive): Add checks for invalid archives.
(get_archive_member_name): Add range checks.
* elfcomm.h (adjust_relative_path): Update prototyoe.
* readelf.c (process_archive): Add range checks.