Go to file
Peter Jones ebc825b549 mkimage: avoid copying relocations for sections that won't be copied.
Some versions of gcc include a plugin called "annobin", and in some
build systems this is enabled by default.  This plugin creates special
ELF note sections to track which ABI-breaking features are used by a
binary, as well as a series of relocations to annotate where.

If grub is compiled with this feature, then when grub-mkimage translates
the binary to another file format which does not strongly associate
relocation data with sections (i.e. when platform is *-efi), these
relocations appear to be against the .text section rather than the
original note section.  When the binary is loaded by the PE runtime
loader, hilarity ensues.

This issue is not necessarily limited to the annobin, but could arise
any time there are relocations in sections that are not represented in
grub-mkimage's output.

This patch seeks to avoid this issue by only including relocations that
refer to sections which will be included in the final binary.

As an aside, this should also obviate the need to avoid -funwind-tables,
-fasynchronous-unwind-tables, and any sections similar to .eh_frame in
the future.  I've tested it on x86-64-efi with the following gcc command
line options (as recorded by -grecord-gcc-flags), but I still need to
test the result on some other platforms that have been problematic in
the past (especially ARM Aarch64) before I feel comfortable making
changes to the configure.ac bits:

GNU C11 7.2.1 20180116 (Red Hat 7.2.1-7) -mno-mmx -mno-sse -mno-sse2 -mno-sse3 -mno-3dnow -msoft-float -mno-stack-arg-probe -mcmodel=large -mno-red-zone -m64 -mtune=generic -march=x86-64 -g3 -Os -freg-struct-return -fno-stack-protector -ffreestanding -funwind-tables -fasynchronous-unwind-tables -fno-strict-aliasing -fstack-clash-protection -fno-ident -fplugin=annobin

Signed-off-by: Peter Jones <pjones@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2018-03-05 14:08:09 +01:00
asm-tests asm-tests/i386-pc: Check that movl is 5 bytes. 2016-09-28 20:31:04 +03:00
build-aux Autogenerate ChangeLog from git changelog. 2015-01-24 17:29:50 +01:00
conf Add support for device-tree-based drivers. 2017-05-08 21:19:59 +02:00
docs grub.texi: Fix typo 2017-08-14 11:36:50 +02:00
grub-core ieee1275: fix build regression in of_path_of_nvme 2018-02-26 10:37:36 +01:00
include aout.h: Fix missing include. 2018-03-05 13:44:55 +01:00
m4 update m4/extern-inline.m4 to upstream version to fix compilation on FreeBSD 2015-03-05 19:25:56 +03:00
po po: Use @SHELL@ rather than /bin/sh. 2017-05-03 12:46:48 +02:00
tests grub-fs-tester: Fix bashism 2017-08-30 21:31:26 +02:00
themes/starfield Starfield theme. 2012-02-23 17:21:38 +01:00
unicode * unicode: Import Unicode 6.0 data. 2011-12-25 16:17:25 +01:00
util mkimage: avoid copying relocations for sections that won't be copied. 2018-03-05 14:08:09 +01:00
.gitignore .gitignore: Add grub-core/build-grub-module-verifier 2016-11-12 12:07:31 +03:00
ABOUT-NLS automake commit without merge history 2010-05-06 11:34:04 +05:30
AUTHORS 2005-09-03 Yoshinori K. Okuji <okuji@enbug.org> 2005-09-03 16:54:27 +00:00
BUGS * BUGS: New file. 2011-01-11 00:06:01 +01:00
COPYING 2007-07-22 Yoshinori K. Okuji <okuji@enbug.org> 2007-07-21 23:32:33 +00:00
ChangeLog-2015 Autogenerate ChangeLog from git changelog. 2015-01-24 17:29:50 +01:00
INSTALL INSTALL: Fix mention of thumb-clang. 2017-02-02 01:11:52 +01:00
Makefile.am Use core2duo for bootcheck test on 64-bit EFI. 2017-03-15 09:20:14 +01:00
Makefile.util.def Makefile.util.def: add $LIBINTL to grub-macbless flags 2016-03-13 08:11:58 +03:00
NEWS NEWS updates 2016-11-22 20:51:54 +03:00
README README: Remove dead link to the wiki 2015-11-06 04:31:23 +01:00
THANKS 2009-12-11 Robert Millan <rmh.grub@aybabtu.com> 2009-12-11 22:44:47 +00:00
TODO TODO: Remove obsolete link 2016-02-12 17:51:52 +01:00
acinclude.m4 Fix -nopie/-nopie check. 2017-01-30 19:38:55 +01:00
autogen.sh autogen: Use cp instead of ln -s. 2015-11-08 18:45:57 +01:00
config.h.in Remove libgcc dependency. 2015-03-03 20:50:37 +01:00
configure.ac Set have_exec to y on cygwin so we have grub_mkrescue. 2017-08-14 16:27:53 +02:00
coreboot.cfg * coreboot.cfg: Add missing file. 2013-11-20 00:52:23 +01:00
geninit.sh automake commit without merge history 2010-05-06 11:34:04 +05:30
gentpl.py arm_coreboot: Support EHCI. 2017-05-08 22:15:05 +02:00
linguas.sh linguas: Don't skip ko.po. 2017-02-04 00:06:57 +01:00

README

This is GRUB 2, the second version of the GRand Unified Bootloader.
GRUB 2 is rewritten from scratch to make GNU GRUB cleaner, safer, more
robust, more powerful, and more portable.

See the file NEWS for a description of recent changes to GRUB 2.

See the file INSTALL for instructions on how to build and install the
GRUB 2 data and program files.

Please visit the official web page of GRUB 2, for more information.
The URL is <http://www.gnu.org/software/grub/grub.html>.

More extensive documentation is available in the Info manual,
accessible using 'info grub' after building and installing GRUB 2.

There are a number of important user-visible differences from the
first version of GRUB, now known as GRUB Legacy. For a summary, please
see:

  info grub Introduction 'Changes from GRUB Legacy'