In grub-core/video/readers/jpeg.c, the height and width of a JPEG image don't
have an upper limit for how big the JPEG image can be. In Coverity, this is
getting flagged as an untrusted loop bound. This issue can also seen in PNG and
TGA format images as well but Coverity isn't flagging it. To prevent this, the
constant IMAGE_HW_MAX_PX is being added to include/grub/bitmap.h, which has
a value of 16384, to act as an artificial limit and restrict the height and
width of images. This value was picked as it is double the current max
resolution size, which is 8K.
Fixes: CID 292450
Signed-off-by: Alec Brown <alec.r.brown@oracle.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
minilzo fails to build on a number of Debian release architectures
(armel, mips64el, mipsel, ppc64el) with errors such as:
../../grub-core/lib/minilzo/minilzo.c: In function 'lzo_memops_get_le16':
../../grub-core/lib/minilzo/minilzo.c:3479:11: error: dereferencing type-punned pointer will break strict-aliasing rules [-Werror=strict-aliasing]
3479 | * (lzo_memops_TU2p) (lzo_memops_TU0p) (dd) = * (const lzo_memops_TU2p) (const lzo_memops_TU0p) (ss); \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../../grub-core/lib/minilzo/minilzo.c:3530:5: note: in expansion of macro 'LZO_MEMOPS_COPY2'
3530 | LZO_MEMOPS_COPY2(&v, ss);
| ^~~~~~~~~~~~~~~~
The latest upstream version is 2.10, so updating to it seems like a good
idea on general principles, and it fixes builds on all the above
architectures.
The update procedure documented in the GRUB Developers Manual worked; I
just updated the version numbers to make it clear that it's been
executed recently.
Signed-off-by: Colin Watson <cjwatson@debian.org>
Forwarded: https://lists.gnu.org/archive/html/grub-devel/2021-11/msg00095.html
Last-Update: 2021-11-29
Patch-Name: minilzo-2.10.patch
This allows the controversial "recovery mode" text to be customised.
Bug-Ubuntu: https://bugs.launchpad.net/bugs/1240360
Forwarded: no
Last-Update: 2013-12-25
Patch-Name: mkconfig-recovery-title.patch
If other operating systems are installed, then automatically unhide the
menu. Otherwise, if GRUB_HIDDEN_TIMEOUT is 0, then use keystatus if
available to check whether Shift is pressed. If it is, show the menu,
otherwise boot immediately. If keystatus is not available, then fall
back to a short delay interruptible with Escape.
This may or may not remain Ubuntu-specific, although it's not obviously
wanted upstream. It implements a requirement of
https://wiki.ubuntu.com/DesktopExperienceTeam/KarmicBootExperienceDesignSpec#Bootloader.
If the previous boot failed (defined as failing to get to the end of one
of the normal runlevels), then show the boot menu regardless.
Author: Richard Laager <rlaager@wiktel.com>
Author: Robie Basak <robie.basak@ubuntu.com>
Forwarded: no
Last-Update: 2015-09-04
Patch-Name: quick-boot.patch
This is kind of a mess, requiring lots of OS-specific code to iterate
over all possible devices. However, we use it in a number of scripts to
discover devices and reimplementing those in terms of something else
would be very complicated.
Author: Dimitri John Ledkov <dimitri.ledkov@canonical.com>
Forwarded: no
Last-Update: 2021-09-24
Patch-Name: restore-mkdevicemap.patch
Additionally, fix the terminfo spelling mistake in
the GRUB development documentation.
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
To give users hint why Argon2, the default in cryptsetup for LUKS2, does
not work.
Signed-off-by: Petr Vorel <pvorel@suse.cz>
Acked-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reviewed-by: Patrick Steinhardt <ps@pks.im>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The os-prober is enabled by default what may lead to potentially
dangerous use cases and borderline opening attack vectors. This
patch disables the os-prober, adds warning messages and updates
GRUB_DISABLE_OS_PROBER configuration option documentation. This
way we make it clear that the os-prober usage is not recommended.
Simplistic nature of this change allows downstream vendors, who
really want os-prober to be enabled out of the box in their
relevant products, easily revert to it's old behavior.
Reported-by: NyankoSec (<nyanko@10x.moe>, https://twitter.com/NyankoSec),
working with SSD Secure Disclosure
Signed-off-by: Alex Burmashev <alexander.burmashev@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Commit 32ddc42c (efi: Only register shim_lock verifier if shim_lock
protocol is found and SB enabled) reintroduced CVE-2020-15705 which
previously only existed in the out-of-tree linuxefi patches and was
fixed as part of the BootHole patch series.
Under Secure Boot enforce loading shim_lock verifier. Allow skipping
shim_lock verifier if SecureBoot/MokSBState EFI variables indicate
skipping validations, or if GRUB image is built with --disable-shim-lock.
Fixes: 132ddc42c (efi: Only register shim_lock verifier if shim_lock
protocol is found and SB enabled)
Fixes: CVE-2020-15705
Fixes: CVE-2021-3418
Reported-by: Dimitri John Ledkov <xnox@ubuntu.com>
Signed-off-by: Dimitri John Ledkov <xnox@ubuntu.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Add a --sbat option to the grub-mkimage tool which allows us to import
an SBAT metadata formatted as a CSV file into a .sbat section of the
EFI binary.
Signed-off-by: Peter Jones <pjones@redhat.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The command is not present in the docs/grub.texi user documentation.
Reported-by: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
There are some more commands that should be restricted when the GRUB is
locked down. Following is the list of commands and reasons to restrict:
* fakebios: creates BIOS-like structures for backward compatibility with
existing OSes. This should not be allowed when locked down.
* loadbios: reads a BIOS dump from storage and loads it. This action
should not be allowed when locked down.
* devicetree: loads a Device Tree blob and passes it to the OS. It replaces
any Device Tree provided by the firmware. This also should
not be allowed when locked down.
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The cutmem and badram commands can be used to remove EFI memory regions
and potentially disable the UEFI Secure Boot. Prevent the commands to be
registered if the GRUB is locked down.
Fixes: CVE-2020-27779
Reported-by: Teddy Reed <teddy.reed@gmail.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The command is not allowed when lockdown is enforced. Otherwise an
attacker can instruct the GRUB to load an SSDT table to overwrite
the kernel lockdown configuration and later load and execute
unsigned code.
Fixes: CVE-2020-14372
Reported-by: Máté Kukri <km@mkukri.xyz>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Now the GRUB can check if it has been locked down and this can be used to
prevent executing commands that can be utilized to circumvent the UEFI
Secure Boot mechanisms. So, instead of hardcoding a list of modules that
have to be disabled, prevent the usage of commands that can be dangerous.
This not only allows the commands to be disabled on other platforms, but
also properly separate the concerns. Since the shim_lock verifier logic
should be only about preventing to run untrusted binaries and not about
defining these kind of policies.
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
It may be useful for scripts to determine whether the GRUB is locked
down or not. Add the lockdown variable which is set to "y" when the GRUB
is locked down.
Suggested-by: Dimitri John Ledkov <xnox@ubuntu.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
When the GRUB starts on a secure boot platform, some commands can be
used to subvert the protections provided by the verification mechanism and
could lead to booting untrusted system.
To prevent that situation, allow GRUB to be locked down. That way the code
may check if GRUB has been locked down and further restrict the commands
that are registered or what subset of their functionality could be used.
The lockdown support adds the following components:
* The grub_lockdown() function which can be used to lockdown GRUB if,
e.g., UEFI Secure Boot is enabled.
* The grub_is_lockdown() function which can be used to check if the GRUB
was locked down.
* A verifier that flags OS kernels, the GRUB modules, Device Trees and ACPI
tables as GRUB_VERIFY_FLAGS_DEFER_AUTH to defer verification to other
verifiers. These files are only successfully verified if another registered
verifier returns success. Otherwise, the whole verification process fails.
For example, PE/COFF binaries verification can be done by the shim_lock
verifier which validates the signatures using the shim_lock protocol.
However, the verification is not deferred directly to the shim_lock verifier.
The shim_lock verifier is hooked into the verification process instead.
* A set of grub_{command,extcmd}_lockdown functions that can be used by
code registering command handlers, to only register unsafe commands if
the GRUB has not been locked down.
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Move the shim_lock verifier from its own module into the core image. The
Secure Boot lockdown mechanism has the intent to prevent the load of any
unsigned code or binary when Secure Boot is enabled.
The reason is that GRUB must be able to prevent executing untrusted code
if UEFI Secure Boot is enabled, without depending on external modules.
Signed-off-by: Marco A Benatto <mbenatto@redhat.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Document the artificially imposed 1 EiB disk size limit and size limitations
with LUKS volumes.
Fix a few punctuation issues.
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
grub-install --pubkey is supported, so we can now document it.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Since commit cd46aa6cef in 2013, grub-install hasn't been a shell
script. The para doesn't really add that much, especially since it's
the user manual, so just drop it.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This has been available since January of 2012 but has not been documented.
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Specifically fix the subsection and drop bogus reference to the GNU/Linux.
Reported-by: Patrick Higgins <higgi1pt@gmail.com>
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Support was implemented in commit c7cb11b21 (probe: Support probing for
msdos PARTUUID).
Signed-off-by: Jacob Kroon <jacob.kroon@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Remove all documentation of and mentions of the uppermem
command from the docs/grub.texi file.
The uppermem command is not implemented in the GRUB source
at all and appears to never have been implemented despite
former plans to add an uppermem command.
To reduce user confusion, this even removes the paragraph
describing how GRUB's uppermem command was supposed to
complement the Linux kernel's mem= parameter.
Signed-off-by: Hans Ulrich Niedermann <hun@n-dimensional.de>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Remove the documentation of the pxe_unload command from the
docs/grub.texi file.
The pxe_unload command is not implemented in the grub source
at this time at all. It appears to have been removed in commit
671a78acb (cleanup pxe and efi network release).
Signed-off-by: Hans Ulrich Niedermann <hun@n-dimensional.de>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
On some devices the ESC key is the hotkey to enter the BIOS/EFI setup
screen, making it really hard to time pressing it right. Besides that
ESC is also pretty hard to discover for a user who does not know it
will unhide the menu.
This commit makes F4, which was chosen because is not used as a hotkey
to enter the BIOS setup by any vendor, also interrupt sleeps / stop the
menu countdown.
This solves the ESC gets into the BIOS setup and also somewhat solves
the discoverability issue, but leaves the timing issue unresolved.
This commit fixes the timing issue by also adding support for keeping
SHIFT pressed during boot to stop the menu countdown. This matches
what Ubuntu is doing, which should also help with discoverability.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Add notes on LVM cache booting to the GRUB manual to help user understanding
the outstanding issue and status.
Signed-off-by: Michael Chang <mchang@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
These were inadvertently lost during the conversion to Gnulib (gnulib:
Upgrade Gnulib and switch to bootstrap tool; commit 35b909062). The
files in po/gettext-patches/ can be imported using "git am" on top of
the gettext tag corresponding to AM_GNU_GETTEXT_VERSION in configure.ac
(currently 0.18.3). They handle translation of messages in shell files,
make msgfmt output in little-endian format, and arrange to use @SHELL@
rather than /bin/sh.
There were some changes solely for the purpose of distributing extra
files; for ease of maintenance, I've added these to
conf/Makefile.extra-dist instead.
Fixes: https://savannah.gnu.org/bugs/?57298
Signed-off-by: Colin Watson <cjwatson@ubuntu.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Add documentation to the GRUB manual that specifies the order netboot
clients use to select a GRUB configuration file.
Also explain that the feature is enabled by default but can be disabled
by setting the "feature_net_search_cfg" environment variable to "n" in
an embedded configuration file.
Signed-off-by: Robert Marshall <rmarshall@redhat.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This patch updates the miniLZO library to a newer version, which among other
things fixes "CVE-2014-4607 - lzo: lzo1x_decompress_safe() integer overflow"
that is present in the current used in GRUB.
It also updates the "GRUB Developers Manual", to mention that the library is
used and describes the process to update it to a newer release when needed.
Resolves: http://savannah.gnu.org/bugs/?42635
Signed-off-by: Peter Jones <pjones@redhat.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
With cryptsetup 2.0, a new version of LUKS was introduced that breaks
compatibility with the previous version due to various reasons. GRUB
currently lacks any support for LUKS2, making it impossible to decrypt
disks encrypted with that version. This commit implements support for
this new format.
Note that LUKS1 and LUKS2 are quite different data formats. While they
do share the same disk signature in the first few bytes, representation
of encryption parameters is completely different between both versions.
While the former version one relied on a single binary header, only,
LUKS2 uses the binary header only in order to locate the actual metadata
which is encoded in JSON. Furthermore, the new data format is a lot more
complex to allow for more flexible setups, like e.g. having multiple
encrypted segments and other features that weren't previously possible.
Because of this, it was decided that it doesn't make sense to keep both
LUKS1 and LUKS2 support in the same module and instead to implement it
in two different modules luks and luks2.
The proposed support for LUKS2 is able to make use of the metadata to
decrypt such disks. Note though that in the current version, only the
PBKDF2 key derival function is supported. This can mostly attributed to
the fact that the libgcrypt library currently has no support for either
Argon2i or Argon2id, which are the remaining KDFs supported by LUKS2. It
wouldn't have been much of a problem to bundle those algorithms with
GRUB itself, but it was decided against that in order to keep down the
number of patches required for initial LUKS2 support. Adding it in the
future would be trivial, given that the code structure is already in
place.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The upcoming support for LUKS2 encryption will require a JSON parser to
decode all parameters required for decryption of a drive. As there is
currently no other tool that requires JSON, and as gnulib does not
provide a parser, we need to introduce a new one into the code base. The
backend for the JSON implementation is going to be the jsmn library [1].
It has several benefits that make it a very good fit for inclusion in
GRUB:
- It is licensed under MIT.
- It is written in C89.
- It has no dependencies, not even libc.
- It is small with only about 500 lines of code.
- It doesn't do any dynamic memory allocation.
- It is testen on x86, amd64, ARM and AVR.
The library itself comes as a single header, only, that contains both
declarations and definitions. The exposed interface is kind of
simplistic, though, and does not provide any convenience features
whatsoever. Thus there will be a separate interface provided by GRUB
around this parser that is going to be implemented in the following
commit. This change only imports jsmn.h from tag v1.1.0 and adds it
unmodified to a new json module with the following command:
curl -L https://raw.githubusercontent.com/zserge/jsmn/v1.1.0/jsmn.h \
-o grub-core/lib/json/jsmn.h
Upstream jsmn commit hash: fdcef3ebf886fa210d14956d3c068a653e76a24e
Upstream jsmn commit name: Modernize (#149), 2019-04-20
[1]: https://github.com/zserge/jsmn
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The grub-mkconfig and 10_linux scripts by default attempt to use a UUID to
set the root kernel command line parameter and the $root GRUB environment
variable.
The former can be disabled by setting the GRUB_DISABLE_LINUX_UUID variable
to "true", but there is currently no way to disable the latter.
The generated grub config uses the search command with the --fs-uuid option
to find the device that has to be set as $root, i.e:
search --no-floppy --fs-uuid --set=root ...
This is usually more reliable but in some cases it may not be appropriate,
so this patch introduces a new GRUB_DISABLE_UUID variable that can be used
to disable searching for the $root device by filesystem UUID.
When disabled, the $root device will be set to the value specified in the
device.map as found by the grub-probe --target=compatibility_hint option.
When setting GRUB_DISABLE_UUID=true, the GRUB_DISABLE_LINUX_UUID and
GRUB_DISABLE_LINUX_PARTUUID variables will also be set to "true" unless
these have been explicitly set to "false".
That way, the GRUB_DISABLE_UUID variable can be used to force using the
device names for both GRUB and Linux.
Signed-off-by: Peter Jones <pjones@redhat.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Nicholas Vinson <nvinson234@gmail.com>
The GRUB_DISABLE_SUBMENU option is different than the others in the sense
that it has to be set to "y" instead of "true" to be enabled.
That causes a lot of confusion to users, some may wrongly set it to "true"
expecting that will work the same than with most options, and some may set
it to "yes" since for other options the value to set is a word and not a
single character.
This patch changes all the grub.d scripts using the GRUB_DISABLE_SUBMENU
option, so they check if it was set to "true" instead of "y", making it
consistent with all the other options.
But to keep backward compatibility for users that set the option to "y" in
/etc/default/grub file, keep testing for this value. And also do it for
"yes", since it is a common mistake made by users caused by this option
being inconsistent with the others.
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Commit 5bc41db756 ("net/dhcp: Add explicit net_dhcp command")
introduced the new command "net_dhcp", which (for now) is an alias for
the existing "net_bootp". Unfortunately the TEXI documentation was not
adjusted accordingly.
Rename the existing paragraph about net_bootp to read net_dhcp instead,
and make the net_bootp stanza point to this new command.
On the way add the newly parsed TFTP_SERVER_NAME and BOOTFILE_NAME
packets to the list of supported DHCP options.
Fixes bug: https://savannah.gnu.org/bugs/?56725
Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The following are two use cases from Rajat Jain <rajatjain@juniper.net>:
1) We have a board that boots Linux and this board itself can be plugged
into one of different chassis types. We need to pass different
parameters to the kernel based on the "CHASSIS_TYPE" information
that is passed by the bios in the DMI/SMBIOS tables.
2) We may have a USB stick that can go into multiple boards, and the
exact kernel to be loaded depends on the machine information
(PRODUCT_NAME etc) passed via the DMI.
Signed-off-by: David Michael <fedora.dm0@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Linux supports root=PARTUUID=<partuuid> boot argument, so add
support for probing it. Compared to the fs UUID, the partition
UUID does not change when reformatting a partition.
For now, only disks using a GPT partition table are supported.
Signed-off-by: Jacob Kroon <jacob.kroon@gmail.com>
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Add a description of the workaround for firmware of older MacBooks
which stalls with a grub-mkrescue ISO image for x86_64-efi target
on an USB stick.
Signed-off-by: Thomas Schmitt <scdbackup@gmx.net>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Some older distros do not contain gettext 0.18. Document the workaround
to use the bootstrap utility on these systems.
Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Current comments forms are annoying, so, some of them are disallowed
starting from now. New rules are more flexible and mostly aligned
with, e.g., Linux kernel comments rules.
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Vladimir Serbinenko <phcoder@google.com>