/patchelf

A small utility to modify the dynamic linker and RPATH of ELF executables

Primary LanguageCGNU General Public License v3.0GPL-3.0

PatchELF is a simple utility for modifying existing ELF executables and libraries. In particular, it can do the following:

  • Change the dynamic loader ("ELF interpreter") of executables:

    $ patchelf --set-interpreter /lib/my-ld-linux.so.2 my-program

  • Change the RPATH of executables and libraries:

    $ patchelf --set-rpath /opt/my-libs/lib:/other-libs my-program

  • Shrink the RPATH of executables and libraries:

    $ patchelf --shrink-rpath my-program

    This removes from the RPATH all directories that do not contain a library referenced by DT_NEEDED fields of the executable or library. For instance, if an executable references one library libfoo.so, has an RPATH /lib:/usr/lib:/foo/lib, and libfoo.so can only be found in /foo/lib, then the new RPATH will be /foo/lib.

    In addition, the --allowed-rpath-prefixes option can be used for further rpath tuning. For instance, if an executable has an RPATH /tmp/build-foo/.libs:/foo/lib, it is probably desirable to keep the /foo/lib reference instead of the /tmp entry. To accomplish that, use:

    $ patchelf --shrink-rpath --allowed-rpath-prefixes /usr/lib:/foo/lib my-program

  • Remove declared dependencies on dynamic libraries (DT_NEEDED entries):

    $ patchelf --remove-needed libfoo.so.1 my-program

    This option can be given multiple times.

  • Add a declared dependency on a dynamic library (DT_NEEDED):

    $ patchelf --add-needed libfoo.so.1 my-program

    This option can be give multiple times.

  • Replace a declared dependency on a dynamic library with another one (DT_NEEDED):

    $ patchelf --replace-needed liboriginal.so.1 libreplacement.so.1 my-program

    This option can be give multiple times.

  • Change SONAME of a dynamic library:

    $ patchelf --set-soname libnewname.so.3.4.5 path/to/libmylibrary.so.1.2.3

Compiling and Testing

./bootstrap.sh
./configure
make
make check
sudo make install

Author

Copyright 2004-2019 Eelco Dolstra edolstra@gmail.com.

License

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.

Release History

0.12 (August 27, 2020):

  • New --clear-symbol-version flag.

  • Better support for relocating NOTE sections/segments.

  • Improved the default section alignment choice.

  • Bug fixes.

0.11 (June 9, 2020):

  • New --output flag.

  • Some bug fixes.

0.10 (March 28, 2019):

  • Many bug fixes. Please refer to the Git commit log:

    https://github.com/NixOS/patchelf/commits/master

    This release has contributions from Adam Trhoň, Benjamin Hipple, Bernardo Ramos, Bjørn Forsman, Domen Kožar, Eelco Dolstra, Ezra Cooper, Felipe Sateler, Jakub Wilk, James Le Cuirot, Karl Millar, Linus Heckemann, Nathaniel J. Smith, Richard Purdie, Stanislav Markevich and Tuomas Tynkkynen.

0.9 (February 29, 2016):

  • Lots of new features. Please refer to the Git commit log:

    https://github.com/NixOS/patchelf/commits/master

    This release has contributions from Aaron D. Marasco, Adrien Devresse, Alexandre Pretyman, Changli Gao, Chingis Dugarzhapov, darealshinji, David Sveningsson, Eelco Dolstra, Felipe Sateler, Jeremy Sanders, Jonas Kuemmerlin, Thomas Tuegel, Tuomas Tynkkynen, Vincent Danjean and Vladimír Čunát.

0.8 (January 15, 2014):

  • Fix a segfault caused by certain illegal entries in symbol tables.

0.7 (January 7, 2014):

  • Rewrite section indices in symbol tables. This for instance allows gdb to show proper backtraces.

  • Added `--remove-needed' option.

0.6 (November 7, 2011):

  • Hacky support for executables created by the Gold linker.

  • Support segments with an alignment of 0 (contributed by Zack Weinberg).

  • Added a manual page (contributed by Jeremy Sanders jeremy@jeremysanders.net).

0.5 (November 4, 2009):

  • Various bugfixes.

  • `--force-rpath' now deletes the DT_RUNPATH if it is present.

0.4 (June 4, 2008):

  • Support for growing the RPATH on dynamic libraries.

  • IA-64 support (not tested) and related 64-bit fixes.

  • FreeBSD support.

  • --set-rpath', --shrink-rpath' and --print-rpath' now prefer DT_RUNPATH over DT_RPATH, which is obsolete. When updating, if both are present, both are updated. If only DT_RPATH is present, it is converted to DT_RUNPATH unless --force-rpath' is specified. If neither is present, a DT_RUNPATH is added unless `--force-rpath' is specified, in which case a DT_RPATH is added.

0.3 (May 24, 2007):

  • Support for 64-bit ELF binaries (such as on x86_64-linux).

  • Support for big-endian ELF binaries (such as on powerpc-linux).

  • Various bugfixes.

0.2 (January 15, 2007):

  • Provides a hack to get certain programs (such as the Belastingaangifte 2005) to work.

0.1 (October 11, 2005):

  • Initial release.