From: "H.J. Lu" <hjl.tools@gmail.com>
To: binutils@sourceware.org
Subject: [PATCH 0/7] ELF: Don't require section header on ELF objects
Date: Sun, 8 Mar 2020 16:42:35 -0700 [thread overview]
Message-ID: <20200308234242.1225816-1-hjl.tools@gmail.com> (raw)
Section header isn't mandatory on ELF executable nor shared library.
This patch set adds a new linker option, -z nosectionheader, to omit
ELF section header when building an executable or shared library, an
objcopy and strip option, --remove-section-header, to remove ELF
section header from an executable or shared library.
The PT_DYNAMIC segment contains DT_HASH/DT_GNU_HASH/DT_MIPS_XHASH,
DT_STRTAB, DT_SYMTAB, DT_STRSZ and DT_SYMENT entries, which can be
used to reconstruct dynamic symbol table when section header isn't
available. For DT_HASH, the number of dynamic symbol table entries
equals the number of chains. For DT_GNU_HASH/DT_MIPS_XHASH, only
defined symbols with non-STB_LOCAL indings are in hash table. Since
in dynamic symbol table, all symbols with STB_LOCAL binding are placed
before symbols with other bindings and all undefined symbols are placed
before defined ones, the highest symbol index in DT_GNU_HASH and
DT_MIPS_XHASH is the highest dynamic symbol table index.
H.J. Lu (5):
bfd: Reconstruct dynamic symbol table from PT_DYNAMIC segment
readelf: Compute dynamic symbol table size from hash table
binutils: Add --remove-section-header tests
ld: Add tests for -z nosectionheader and --remove-section-header
ld: Add -z nosectionheader test to bootstrap.exp
Kaylee Blake (2):
ELF: Don't require section header on ELF objects
ld: Add a simple test for -z nosectionheader
bfd/bfd-in2.h | 8 +-
bfd/bfd.c | 8 +-
bfd/elf-bfd.h | 8 +
bfd/elf.c | 443 ++++++++++++++++++
bfd/elfcode.h | 174 ++++++-
bfd/elflink.c | 148 ++++--
bfd/elfxx-target.h | 6 +-
binutils/NEWS | 3 +
binutils/doc/binutils.texi | 12 +
binutils/objcopy.c | 54 ++-
binutils/readelf.c | 226 ++++-----
binutils/testsuite/binutils-all/objcopy.exp | 13 +
.../testsuite/binutils-all/remove-header-1.d | 8 +
ld/NEWS | 3 +
ld/emultempl/elf.em | 4 +
ld/ld.h | 3 +
ld/ld.texi | 6 +
ld/ldlang.c | 4 +
ld/lexsup.c | 12 +
ld/testsuite/ld-bootstrap/bootstrap.exp | 10 +-
ld/testsuite/ld-elf/hash.d | 8 +-
ld/testsuite/ld-elf/no-section-header.exp | 336 +++++++++++++
ld/testsuite/ld-elf/nosectionheader.d | 12 +
ld/testsuite/ld-elf/pr13195.d | 2 +-
ld/testsuite/ld-elf/pr22393-2a-no-sec-hdr.nd | 3 +
ld/testsuite/ld-elf/pr22393-2a-no-sec-hdr.rd | 20 +
ld/testsuite/ld-elf/pr22393-2a-sec-hdr.rd | 19 +
ld/testsuite/ld-elf/pr22393-2b-no-sec-hdr.nd | 3 +
ld/testsuite/ld-elf/pr22393-2b-no-sec-hdr.rd | 20 +
.../ld-elf/pr22393-2b-static-no-sec-hdr.rd | 12 +
ld/testsuite/ld-elf/start-noheader.rd | 11 +
.../ld-elf/start-shared-noheader-gnu.rd | 22 +
.../ld-elf/start-shared-noheader-sysv.rd | 22 +
ld/testsuite/ld-elf/start-shared-noheader.nd | 5 +
ld/testsuite/ld-elfvsb/hidden2.d | 2 +-
ld/testsuite/ld-mips-elf/hash2.d | 8 +-
36 files changed, 1458 insertions(+), 200 deletions(-)
create mode 100644 binutils/testsuite/binutils-all/remove-header-1.d
create mode 100644 ld/testsuite/ld-elf/no-section-header.exp
create mode 100644 ld/testsuite/ld-elf/nosectionheader.d
create mode 100644 ld/testsuite/ld-elf/pr22393-2a-no-sec-hdr.nd
create mode 100644 ld/testsuite/ld-elf/pr22393-2a-no-sec-hdr.rd
create mode 100644 ld/testsuite/ld-elf/pr22393-2a-sec-hdr.rd
create mode 100644 ld/testsuite/ld-elf/pr22393-2b-no-sec-hdr.nd
create mode 100644 ld/testsuite/ld-elf/pr22393-2b-no-sec-hdr.rd
create mode 100644 ld/testsuite/ld-elf/pr22393-2b-static-no-sec-hdr.rd
create mode 100644 ld/testsuite/ld-elf/start-noheader.rd
create mode 100644 ld/testsuite/ld-elf/start-shared-noheader-gnu.rd
create mode 100644 ld/testsuite/ld-elf/start-shared-noheader-sysv.rd
create mode 100644 ld/testsuite/ld-elf/start-shared-noheader.nd
--
2.24.1
next reply other threads:[~2020-03-08 23:42 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-08 23:42 H.J. Lu [this message]
2020-03-08 23:42 ` [PATCH 1/7] " H.J. Lu
2020-03-08 23:42 ` [PATCH 2/7] bfd: Reconstruct dynamic symbol table from PT_DYNAMIC segment H.J. Lu
2020-03-08 23:42 ` [PATCH 3/7] readelf: Compute dynamic symbol table size from hash table H.J. Lu
2020-03-08 23:42 ` [PATCH 4/7] ld: Add a simple test for -z nosectionheader H.J. Lu
2020-03-08 23:42 ` [PATCH 5/7] binutils: Add --remove-section-header tests H.J. Lu
2020-03-08 23:42 ` [PATCH 6/7] ld: Add tests for -z nosectionheader and --remove-section-header H.J. Lu
2020-03-08 23:42 ` [PATCH 7/7] ld: Add -z nosectionheader test to bootstrap.exp H.J. Lu
2020-03-19 0:48 ` [PATCH 0/7] ELF: Don't require section header on ELF objects Fangrui Song
2020-03-19 1:32 ` H.J. Lu
2020-03-19 1:45 ` Kaylee Blake
2020-05-02 14:19 ` H.J. Lu
[not found] ` <06c41571-09ef-d107-ee21-38af17f6d20b@gmail.com>
2020-08-07 13:11 ` Has FSF stopped processing copyright paperwork? H.J. Lu
2020-08-07 13:28 ` Richard Biener
2020-08-14 15:25 ` Kaylee Blake
2021-04-02 13:45 ` H.J. Lu
2021-04-02 15:21 ` Mark Wielaard
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200308234242.1225816-1-hjl.tools@gmail.com \
--to=hjl.tools@gmail.com \
--cc=binutils@sourceware.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).