Commit Graph

53 Commits

Author SHA1 Message Date
markj
b6697ced84 elfcopy: Clear errors after fetching the shstrtab index.
Otherwise a future call to elf_errno() will return a non-zero value.
update_shdr(), for example, treats any errors associated with the ELF
descriptor as fatal.  Clear the error per the first example in
elf_errmsg.3.

Convert to elf_getshdrstrndx() while here since elf_getshstrndx() is
apparently deprecated.

Reported by:	royger
Reviewed by:	emaste
MFC after:	3 days
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D20852
2019-07-04 15:07:19 +00:00
markj
da2dec8da8 elfcopy: Provide a size hint when creating the section string table.
Use the input file's .shstrtab size as the hint if it exists.  This
gives a small performance improvement when processing files with
many sections.

Reviewed by:	emaste
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D20544
2019-06-26 16:35:37 +00:00
markj
bec7330290 elfcopy: Use libelftc's string table routines to build .shstrtab.
This replaces some hand-rolled routines and is substantially faster
since libelftc uses a hash table for lookups and insertions, whereas
elfcopy would perform a linear scan of the table.

PR:		234949
Reviewed by:	emaste
MFC after:	2 weeks
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D20473
2019-06-04 18:34:05 +00:00
markj
c2f715e33c elfcopy: Use elf_getscn() instead of iterating over all sections.
When removing a section, we would loop over all sections looking for
a corresponding relocation section.  With r348652 it is much faster
to just use elf_getscn().

PR:		234949
Reviewed by:	emaste
MFC after:	2 weeks
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D20471
2019-06-04 18:29:08 +00:00
markj
7c7f66ca44 elfcopy: Optimize for insertions at the end of the section list.
This is the common case when strip(1) is creating the output file.
The change provides a significant speedup when running on ELF files with
many sections.

PR:		234949
Reviewed by:	emaste
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D20444
2019-05-30 15:28:48 +00:00
markj
f94996b3a3 elfcopy: Remove an unneeded memset.
Reviewed by:	emaste, trasz
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D20445
2019-05-30 15:26:39 +00:00
emaste
b54d7a9715 Update to ELF Tool Chain r3668
Highlights:
- Make sure that only TLS sections are sorted into TLS segment.
- Fixed multiple errors in "Section to Segment mapping".
- Man page updates
- ar improvements
- elfcopy: avoid filter_reloc uninitialized variable for rela
- elfcopy: avoid stripping relocations from static binaries
- readelf: avoid printing directory in front of absolute path
- readelf: add NT_FREEBSD_FEATURE_CTL FreeBSD note type
- test improvements

NOTES:

Some of these changes originated in FreeBSD and simply reduce diffs
between contrib and vendor.

ELF Tool Chain ar is not (currently) used in FreeBSD, and there are
improvements in both FreeBSD and ELF Tool Chain ar that are not in
the other.

Sponsored by:	The FreeBSD Foundation
2019-01-10 14:35:23 +00:00
emaste
9447c73201 objcopy: restore behaviour required by GCC's build
In r339350 filter_reloc() was removed, to fix the case of stripping
statically linked binaries with relocations (which may come from ifunc
use, for example).  As a side effect this changed the behaviour when
stripping object files - the output was broken both before and after
r339350, in different ways.  Unfortunately GCC's build process relies
on the previous behaviour, so:

- Revert r339350, restoring filter_reloc().
- Fix an unitialized variable use (commited as r3638 in ELF Tool Chain).
- Change filter_reloc() to omit relocations referencing removed
  symbols, while retaining relocations with no symbol reference.
- Retain the entire relocation section if it references the dynamic
  symbol table (fix from kaiw in D17596).

PR:		232176
Reported by:	antoine
Reviewed by:	kaiw
MFC with:	r339350
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D17596
2018-10-20 17:27:53 +00:00
emaste
9ed40b5bee elfcopy: delete filter_reloc, it is broken and unnecessary
elfcopy contained logic to filter individual relocations in STRIP_ALL
mode.  However, this is not valid; relocations emitted by the linker are
required, unless they apply to an entire section being removed (which is
handled by other logic in elfcopy).

Note that filter_reloc was also buggy: for RELA relocation sections it
operated on uninitialized rel.r_info resulting in invalid operation.

The logic most likely needs to be inverted: instead of removing
relocations because their associated symbols are being removed, we must
keep symbols referenced by relocations.  That said, in practice we do
not encounter this code path today: objects being stripped are either
dynamically linked binaries which retain .dynsym, or static binaries
with no relocations.

Just remove filter_reloc.  This fixes certain cases including statically
linked binaries containing ifuncs.  Stripping binaries with relocations
referencing removed symbols was already broken, and after this change
may still be broken in a different way.

PR:		232176
Reviewed by:	kaiw, kib, markj
Approved by:	re (rgrimes)
MFC after:	1 month
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D17519
2018-10-13 21:26:07 +00:00
jhb
620b8f1d69 Fix objcopy for little-endian MIPS64 objects.
MIPS64 does not store the 'r_info' field of a relocation table entry as
a 64-bit value consisting of a 32-bit symbol index in the high 32 bits
and a 32-bit type in the low 32 bits as on other architectures.  Instead,
the 64-bit 'r_info' field is really a 32-bit symbol index followed by four
individual byte type fields.  For big-endian MIPS64, treating this as a
64-bit integer happens to be compatible with the layout expected by other
architectures (symbol index in upper 32-bits of resulting "native" 64-bit
integer).  However, for little-endian MIPS64 the parsed 64-bit integer
contains the symbol index in the low 32 bits and the 4 individual byte
type fields in the upper 32-bits (but as if the upper 32-bits were
byte-swapped).

To cope, add two helper routines in gelf_getrel.c to translate between the
correct native 'r_info' value and the value obtained after the normal
byte-swap translation.  Use these routines in gelf_getrel(), gelf_getrela(),
gelf_update_rel(), and gelf_update_rela().  This fixes 'readelf -r' on
little-endian MIPS64 objects which was previously decoding incorrect
relocations as well as 'objcopy: invalid symbox index' warnings from
objcopy when extracting debug symbols from kernel modules.

Even with this fixed, objcopy was still crashing when trying to extract
debug symbols from little-endian MIPS64 modules.  The workaround in
gelf_*rel*() depends on the current ELF object having a valid ELF header
so that the 'e_machine' field can be compared against EM_MIPS.  objcopy
was parsing the relocation entries to possibly rewrite the 'r_info' fields
in the update_relocs() function before writing the initial ELF header to
the destination object file.  Move the initial write of the ELF header
earlier before copy_contents() so that update_relocs() uses the correct
symbol index values.

Note that this change should really go upstream.  The binutils readelf
source has a similar hack for MIPS64EL though I implemented this version
from scratch using the MIPS64 ABI PDF as a reference.

Discussed with:	jkoshy
Reviewed by:	emaste, imp
Approved by:	re (gjb, kib)
MFC after:	1 month
Differential Revision:	https://reviews.freebsd.org/D15734
2018-09-05 20:51:53 +00:00
markj
eaf95127f8 Pass the right sizes to malloc() and realloc().
Reported by:	scan-build, via Mark Millard
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D16180
2018-07-12 18:48:53 +00:00
phil
58ce5b116e Handle thread-local storage (TLS) segments correctly when
copying (objcopy) and displaying (readelf) them.

PR:		227552
Submitted by:	kaiw (maintainer)
Reported by:	jachmann@unitix.org
Reviewed by:	phil
MFC after:	1 day
2018-05-14 05:21:18 +00:00
emaste
994b0b9af9 Update ELF Tool Chain to r3614
MFC after:	1 week
Relnotes:	Yes
Sponsored by:	The FreeBSD Foundation
2018-04-27 13:59:24 +00:00
emaste
eec2e2505f elfcopy: copy raw (untranslated) contents to binary output
Previously elfcopy used elf_getdata to obtain data from ELF sections
being copied to binary output, but elf_getdata returns data that has
been translated - that is, data is in host byte order. When the host and
target differ in endianness (e.g., converting a big-endian MIPS ELF
object to binary on an x86 host) this resulted in byte-swapped data in
certain sections such as .dynamic.

Instead use elf_rawdata to keep data in the original, target endianness.

Reported by:	Hiroki Mori <yamori83@yahoo.co.jp>, Bill Yuan
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
2018-01-02 14:07:55 +00:00
emaste
115c54a7b5 elfcopy: allow empty symbol list files
Reported by:	bz
MFC after:	2 weeks
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D10441
2017-04-24 14:51:53 +00:00
emaste
be13fe9688 elfcopy: document --strip-symbols=filename in the man page
Reported by:	bz
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
2017-04-20 13:57:53 +00:00
emaste
ffb40783fd Update ELF Tool Chain to upstream r3520
Highlights of changes between r3490 and r3520:

- Improve C++ demangling
- Improve compatibility with Binutils tools wrt. error messages
- Handle additional types/sections/etc. in readelf and elfdump
- addr2line, cxxfilt: use setvbuf to set line buffering for filter use

PR:		218395
MFC after:	2 weeks
Relnotes:	Yes
Sponsored by:	The FreeBSD Foundation
2017-04-17 23:56:48 +00:00
emaste
e881bc92a3 elfcopy: remove temporary ELF file when converting from binary
Previously a command like

  objcopy --input-target binary --output-target elf64-x86-64-freebsd \
    binary_file object.o

would leave a temporary file behind.

ELF Tool Chain ticket #543

Reported by:	Roger Marquis
MFC after:	2 weeks
Sponsored by:	The FreeBSD Foundation
2017-03-30 17:37:12 +00:00
emaste
d67c23c6f6 elfcopy: fix PE object section name corruption and crash
Fixed a bug that the PE object section names are generated incorrectly
using the section name table found in the original input ELF object
instead of the intermediate ELF object.

Ticket:		#541

Do not try to copy section content from a NULL d_buf when creating
uninitialized data COFF section for PE object.

Ticket:		#540

Obtained from:	ELF Tool Chain r3507, r3508
MFC after:	1 week
2016-12-27 17:31:07 +00:00
emaste
6c4cea19a9 elfcopy: select mode by the end of the program name
The mode of operation (elfcopy, mcs, or strip) is chosen based on the
program name.  Broaden this to allow a substring match at the end of the
name to allow prefixes - for example, bsdstrip or aarch64-freebsd-strip.

This improves use of these tools as drop-in replacements for GNU objcopy
and strip, which are often built with a limited set of supported targets
and installed with a target prefix for cross tools.

Reviewed by:	dim
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D1663
2016-10-22 23:49:06 +00:00
emaste
d95438aeec Update to ELF Tool Chain r3490
Improvements include:
 * readelf: report all relocation types in rel/rela for MIPS N64
 * readelf: add ELFOSABI_ARM_AEABI
 * elfdump: add ELFOSABI_ARM_AEABI and ELFOSABI_ARM
 * Add recent RISC-V relocations
 * elfcopy: use elftc_timestamp, to support SOURCE_DATE_EPOCH

Sponsored by:	The FreeBSD Foundation
2016-08-31 15:05:04 +00:00
emaste
ff68c01f4f elfcopy: correct comment typo in r304151 2016-08-15 23:20:55 +00:00
emaste
bfe8313bbf elfcopy: silence GCC 5.3 unitialized variable warning
Although it's a false positive there is little cost to initializing it
always.

Submitted by:	adrian
2016-08-15 11:54:39 +00:00
bdrewery
3456e2d15b Use the in-tree sys/elf_common.h to build libelftc.
This fixes build failures on older releases that lack various
definitions such as EM_AARCH64 (which was unfixed before this).

Revert all of the recent compatibility changes that worked around this
problem.

This uses the same method of using the in-tree header as lib/libelf,
lib/libdwarf and usr.bin/readelf.

Reviewed by:	emaste
Sponsored by:	EMC / Isilon Storage Division
Differential Revision:	https://reviews.freebsd.org/D6734
2016-06-05 23:05:14 +00:00
emaste
c5d27b0315 Update to ELF Tool Chain r3477
This fixes a EFI/PE header issue that prevented elfcopy-produced .efi
files from working with Secure Boot:

  Make sure section raw size is always padded to multiple of
  FileAlignment from the optional header, as requested by the PE
  specification. This change should reduce the diff between PE image
  generated by Binutils objcopy and elftoolchain elfcopy.

Submitted by:	kaiw
Reported by:	ambrisko
2016-05-25 20:56:30 +00:00
emaste
70ecb891fe elftoolchain: backwards compatability for ELFOSABI_CLOUDABI definition
It is not provided by sys/elf_common.h on older releases or -current
before March 2015.

Reported by:	Jenkins
2016-05-21 15:38:40 +00:00
emaste
e1afa8a663 Update to ELF Tool Chain r3475
Improvements include:

 * Add support for reporting and handling a number of new constants in
   various tools, including:
    * CloudABI OSABI
    * DT_TLSDESC_*
    * i386, MIPS, SPARC and amd64 relocations

 * C++ demangler bug fixes

 * Man page updates

 * Improved input validation in several tools

This update also reduces diffs against upstream as a number of fixes
included in upstream were previously cherry-picked into FreeBSD.

Sponsored by:	The FreeBSD Foundation
2016-05-20 17:24:34 +00:00
emaste
0ecbc86fe5 elfcopy: map all !alnum characters to '_' in binary input symbol names
This matches bfd and gold.

Obtained from:	ELF Tool Chain r3445
Sponsored by:	The FreeBSD Foundation
2016-04-20 19:13:00 +00:00
emaste
6f846e4655 elfcopy: fix symbol table handling when sections come after symtab/strtab
Fix a symbol table handling bug in elfcopy: elfcopy puts .symtab,
  .strtab and .shstrtab sections in the end of the output object.  If
  the input objects have more sections after any of these 3 sections,
  the section table will be reordered, and in that case the section
  symbols should be regenerated for relocations.

  The bug is triggered since newer clang puts .strtab section in the
  beginning of the object produced.

   Ticket: #525

Reported by:	royger
Obtained from:	ELF Tool Chain r3443
2016-04-15 19:06:36 +00:00
emaste
d86d00c49d elfcopy: overhaul of LMA handling
Merge ELF Tool Chain r3434:

    Previously, elfcopy defines:

    VMA:  section virtual address
    LMA:  PHDR(p_vaddr)

    While binutils(libbfd) defines:

    VMA:  section virtual address and PHDR(p_vaddr).
    LMA:  PHDR(p_paddr)

    For elfcopy, p_paddr is considered not meaningful and is always set
    to the same value as p_vaddr.

    elfcopy was implemented that way because I thought p_paddr is not
    used/meaningful according to the ELF ABI. However it turned out
    p_paddr is at least used in some ELF files, e.g. the FreeBSD kernel.

    This change made elfcopy treat p_paddr as LMA, same as libbfd.

    (However, some VMA/LMA related command line option still need tweaking
    to make them compatible with binutils objcopy. This will be improved
    later)

    Ticket: #524

And typo fixes in r3435 and r3436.

This fixes the Xen kernel build.

Submitted by:	kaiw
Tested by:	royger
2016-03-24 20:13:17 +00:00
emaste
4a32de26c7 elfcopy: fail if debug link target is empty
An empty debug link target previously returned a confusing and incorrect
error like "objcopy: fread failed: No error: 0". Now, return an explicit
error.

GNU objcopy allows an empty file as the debug link target. However,
that case is nonsensical so diverging from GNU behaviour is fine.

Reviewed by:	bdrewery
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D5541
2016-03-04 18:28:19 +00:00
emaste
284f6cde63 Allow elfcopy to convert between two non-ELF formats
If the output object is not an ELF file, choose an arbitrary ELF format
for the intermediate file. srec, ihex and binary formats are independent
of class, endianness and machine type so these choices do not affect the
output.

ELF Tool Chain ticket #517

Reviewed by:	kai
Obtained from:	ELF Tool Chain r3411
2016-02-16 14:03:25 +00:00
emaste
a6ae90983e Update ELF Tool Chain to upstream rev 3400
Some notable improvements include:

readelf:
- Add AArch64 relocation definitions.
- Report value of unknown relocation types.

elfcopy:
- Consider symbols with STB_GNU_UNIQUE binding as global symbols.
- Fixed support for VMA adjustment for loadable sections found
  in relocatable objects.
- Handle nameless global symbols.
- Improve wildcard matching for !-prefixed symbols.
- Add PE/COFF support.

elfdump:
- Improve section type reporting.
- Add MIPS-specific section types.

This update also includes a significant number of bug fixes.

PR:		207091 [exp-run]
Sponsored by:	The FreeBSD Foundation
2016-02-12 20:54:02 +00:00
emaste
8d8726ea86 Update to ELF Tool Chain r3272
Highlights (not already in the FreeBSD tree):
 - addr2line: Speed up and support searching inlined functions
 - addr2line: Support -i, -a, -p options
 - readelf: Add some ARM relocation types
 - readelf, libelf: Avoid reading beyond end of buffer/file

Relnotes:	Yes
Sponsored by:	The FreeBSD Foundation
2015-12-11 20:28:27 +00:00
emaste
c90cc6d115 elfcopy: include extension but replace . when converting from binary
The change in r291958 was not consistent with GNU objcopy. The start,
end and size symbols created for ELF objects converted from binary need
to include the full filename including the extension, but with the
periods replaced with underscores.

Reviewed by:	imp
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D4474
2015-12-11 18:47:41 +00:00
emaste
b4974472b4 elfcopy: exclude extension when converting from binary
When converting from binary to ELF, elfcopy creates symbols
_binary_<filename>_start_, _binary_<filename>_end, and
_binary_<filename>_size. For compatibility with GNU objcopy (and to
produce sensible symbol names) the extension must be stripped off.

Reviewed by:	imp
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D4238
2015-12-07 20:21:12 +00:00
emaste
ac41e8b0a6 Update to ELF Tool Chain r3250
Highlights (not already in the FreeBSD tree):
  - addr2line: Fixed multiple memory leaks related to DIE allocation
  - readelf: improve sh_link validation
  - various man page improvements

Sponsored by:	The FreeBSD Foundation
2015-10-09 17:46:05 +00:00
emaste
9d2a9401e6 elfcopy: Handle objects without a ".shstrtab" section string table
As of LLVM revision 238073, LLVM stores symbols and section names in
the same string table.  From the upstream commit mesage:

  With the scheme of naming sections like ".text.foo" where foo is a
  symbol, there is a big potential saving in using a single one.

This is a cherry-pick of ELF Tool Chain revision 3225.

Sponsored by:	The FreeBSD Foundation
2015-06-13 14:24:31 +00:00
emaste
aa01a21e0c Update to ELF Tool Chain r3223
Highlights (upstream revisions):
 - Fix SHT_GROUP handling in elfcopy/strip (3206 3220 3221)
 - Misc elfcopy / strip bug fixes (3215 3216 3217)
 - Many C++ demangler improvements (3199 3200 3201 3202 3203 3204 3205
   3208 3210 3211 3212)
 - Improve GNU binutils compatibility in elfcopy / strip (3213 3214)
 - Add -g option to readelf(1): dump contents of section groups (3219)
 - Add EM_IAMCU 32-bit Intel MCU (3198)

Also add a compat #define for building with older FreeBSD ELF headers.
The GRP_COMDAT flag was added to elf_common.h in r283110, but it's not
available during the bootstrap build.  It is also convenient to be able
to build on older hosts.

Thanks to antoine@ for tracking down issues through multiple exp-runs
and to kaiw@ for fixing.

PR:		198611 (exp-run), 200350
Sponsored by:	The FreeBSD Foundation
2015-05-27 14:28:19 +00:00
emaste
a4c24f2588 Update to ELF Tool Chain r3197
Highlights:
 - Fix man page markup, whitespace, and typos
 - Fix sh_info of SHT_GROUP section to point to the correct string
 - Improve validation in readelf and elfcopy/strip
 - Handle DWARF 4's DW_AT_high_pc in addr2line

Sponsored by:	The FreeBSD Foundation
2015-05-14 19:48:15 +00:00
emaste
55208361ba Update elftoolchain to upstream revision 3179
Some notable changes:
- libdwarf: Fixed DWARF4 line section
- elfcopy: Implement --localize-hidden
- nm: handle object name referenced by DW_AT_specification
- elfcopy: Add --strip-dwo and --extract-dwo options for split DWARF
- readelf: add remaining arm64 dynamic relocation names
- nm: Avoid integer overflow in value comparison

Relnotes:	Yes
Sponsored by:	The FreeBSD Foundation
2015-04-01 01:08:01 +00:00
emaste
a86377a7d0 Update elftoolchain to upstream revision 3163
Most of our changes have now been committed upstream, so this change is
largely bookkeeping.

Sponsored by:	The FreeBSD Foundation
2015-02-17 15:19:58 +00:00
emaste
b4f4496909 Preserve hard & symbolic links when modifying source file
Strip is often used to modify existing files, rather than creating new
files. If the existing file has hard links or is a symbolic link, act as
if editing the file in place and preserve the links.

Reported by:	luigi
Reviewed by:	imp, rpaulo
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D1682
2015-01-28 18:37:09 +00:00
emaste
f5b1a66d7a elfcopy: Avoid divide-by-0 on section alignment 0
According to ELF ABI, alignment 0 and 1 has the same meaning: the
section has no alignment constraints.

PR:		196715
Sponsored by:	The FreeBSD Foundation
2015-01-14 14:49:58 +00:00
emaste
89ea455074 Update elftoolchain to upstream rev 3136
This fixes two strip(1) issues found during ports exp-run and adds a
string hash implementation which significantly speeds up certain
operations on objects with large numbers of symbols.

This also improves libdwarf handling for stripped objects with
.eh_frame or .debug_frame (but not other debug) sections.

PR:		196107
Sponsored by:	The FreeBSD Foundation
2014-12-30 03:25:42 +00:00
emaste
46be049bf4 Update elftoolchain to upstream rev 3130
This brings a number of fixes to elfcopy/strip and DWARF4 improvements.

Sponsored by:	The FreeBSD Foundation
2014-12-24 03:13:16 +00:00
emaste
7740946485 Set up default shstrtab entries at shstrtab initialization
Instead of waiting until the addition of the first non-default entry.
This fixes a segfault when strip(1) is asked to remove every section from
an object file.

Upstream elftoolchain ticket 463

Reviewed by:	imp
Sponsored by:	The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D1341
2014-12-22 16:31:09 +00:00
emaste
c39f1f3223 Include section name in strip warning message 2014-12-18 19:09:59 +00:00
emaste
df55c61fa5 Do not strip all when stripping an explicit symbol
When requested to strip specific symbols (-N flag) the default should be
to strip nothing (other than the requested symbols). This is consistent
with binutils strip(1).

PR:		196038
Reviewed by:	imp
Sponsored by:	The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D1327
2014-12-17 14:46:21 +00:00
emaste
50872743f9 Correct elftoolchain strip(1) memory size calculation
Calculate the segment's memory size (p_memsz) using the virtual
addresses, not the file offsets. Otherwise padding preceeding SHT_NOBITS
sections may be excluded from the calculation, resulting in a segment
that is too small.

PR:		195653
Sponsored by:	The FreeBSD Foundation
2014-12-15 18:18:57 +00:00