If grub is signed with a key that's in the trusted EFI keyring, an attacker
can point a boot entry at grub rather than at shim and grub will fail to
locate the shim verification protocol. This would then allow booting an
arbitrary kernel image. Fail validation if Secure Boot is enabled and we
can't find the shim protocol in order to prevent this.
Basic usage would look something like this:
gptprio.next -d usr_dev -u usr_uuid
linuxefi ($usr_dev)/boot/vmlinuz mount.usr=PARTUUID=$usr_uuid
After booting the system should set the 'successful' bit on the
partition that was used.
In order to do anything with partition GUIDs they need to be stored in a
proper structure like the partition type GUIDs. Additionally add an
initializer macro to simplify defining both GUID types.
The first hint of something practical, a command that can restore any of
the GPT structures from the alternate location. New test case must run
under QEMU because the loopback device used by the other unit tests does
not support writing.
The header location fields refer to 'this header' and 'alternate header'
respectively, not 'primary header' and 'backup header'. The previous
field names are backwards for the backup header.
This module is a new implementation for reading GUID Partition Tables
which is much stricter than the existing part_gpt module and exports GPT
data directly instead of the generic grub_partition structure. It will
be the basis for modules that need to read/write/update GPT data.
The current code does nothing more than read and verify the table.
Hi,
Fedora's patch to forbid insmod in UEFI Secure Boot environments is fine
as far as it goes. However, the insmod command is not the only way that
modules can be loaded. In particular, the 'normal' command, which
implements the usual GRUB menu and the fully-featured command prompt,
will implicitly load commands not currently loaded into memory. This
permits trivial Secure Boot violations by writing commands implementing
whatever you want to do and pointing $prefix at the malicious code.
I'm currently test-building this patch (replacing your current
grub-2.00-no-insmod-on-sb.patch), but this should be more correct. It
moves the check into grub_dl_load_file.
In util/getroot and efidisk slightly modify exitsing comment to mostly
retain it but still make GCC7 compliant with respect to fall through
annotation.
In grub-core/lib/xzembed/xz_dec_lzma2.c it adds same comments as
upstream.
In grub-core/tests/setjmp_tets.c declare functions as "noreturn" to
suppress GCC7 warning.
In grub-core/gnulib/regexec.c use new __attribute__, because existing
annotation is not recognized by GCC7 parser (which requires that comment
immediately precedes case statement).
Otherwise add FALLTHROUGH comment.
Closes: 50598
Fixed loading of ACPI tables on EFI (side effect was apparent memory
corruption ranging from unpredictable behavior to system reset).
Reported by Nando Eva <nando4eva@ymail.com>
iPXE adds Simple File System Protocol to loaded image handle, as side
effect it also adds Block IO protocol (according to comments, to work
around some bugs in EDK2). GRUB assumes that every device with Block IO
is disk and skips network initialization entirely. But iPXE Block IO
implementation is just a stub which always fails for every operation
so cannot be used. Attempt to detect and skip such devices.
We are using media ID which iPXE sets to "iPXE" and block IO size in
hope that no real device would announce 1B block ...
Closes: 50518
1. Make sure files are not multiple of block size. This will ensure tail packing
for squash4 and may also trigger more codes paths in other filesystems.
2. Call mksquashfs with -always-use-fragments to force tail packing.
UEFI 2.6 9.3.6.4 File Path Media Device Path says that Path Name is
"A NULL-terminated Path string including directory and file names".
Strip final NULL from Path Name in each File Path node when constructing
full path. To be on safe side, strip all of them.
Fixes failure chainloading grub from grub, when loaded grub truncates
image path and does not find its grub.cfg.
https://bugzilla.opensuse.org/show_bug.cgi?id=1026344
This was triggered by commit ce95549cc54b5d6f494608a7c390dba3aab4fba7;
before it we built Path Name without trailing NULL, and apparently all
other bootloaders use single File Path node, thus not exposing this bug.
1. Do not assume block list and fragment are mutually exclusive. Squash
can pack file tail as fragment (unless -no-fragments is specified); so
check read offset and read either from block list or from fragments as
appropriate.
2. Support sparse files with zero blocks.
3. Fix fragment read - frag.offset is absolute fragment position,
not offset relative to ino.chunk.
Reported and tested by Carlo Caione <carlo@endlessm.com>
In case of GRUB we put remapper after domain pages and not at 0x0.
In this case we use max_addr to put remapper. Unfortunately we increment
max_addr as well in this case resulting in virt mapping mapping page
at old max_addr and trying to boot using new max_addr.
Closes 46014.
The current documentation for the special environment variable
"default" is confusing and unclear. This patch attempts to clean it
up.
In particular, the current documentation refers to the "number or
title", but then in the example it gives, the menu entries and
submenus all have numbers *in* their title; furthermore, there is no
example given about how to choose the number, or any indication about
whether counting is zero-indexed or 1-indexed.
Having a cleaner example and presenting all variants (numeric, title,
and id) should make it clearer to the user.
Signed-off-by: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
Unified Extensible Firmware Interface Specification, Version 2.6,
section 2.3.4, x64 Platforms, boot services, says among others:
The stack must be 16-byte aligned. So, do it. Otherwise OS may
boot only by chance as it happens right now.
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Matthew Garrett
Michael Marineau
Colin Watson
Matthew Garrett
Vladimir Serbinenko
Andrei Borzenkov
Daniel Kahn Gillmor
Daniel Kiper