commit 92bfc33db9 ("efi: Free malloc regions on exit")
introduced memory freeing in grub_efi_fini(), which is
used not only by exit path but by halt/reboot one as well.
As result of memory freeing, code and data regions used by
modules, such as halt, reboot, acpi (used by halt) also got
freed. After return to module code, CPU executes, filled
by UEFI firmware (tested with edk2), 0xAFAFAFAF pattern as
a code. Which leads to #UD exception later.
grub> halt
!!!! X64 Exception Type - 06(#UD - Invalid Opcode) CPU Apic ID - 00000000 !!!!
RIP - 0000000003F4EC28, CS - 0000000000000038, RFLAGS - 0000000000200246
RAX - 0000000000000000, RCX - 00000000061DA188, RDX - 0A74C0854DC35D41
RBX - 0000000003E10E08, RSP - 0000000007F0F860, RBP - 0000000000000000
RSI - 00000000064DB768, RDI - 000000000832C5C3
R8 - 0000000000000002, R9 - 0000000000000000, R10 - 00000000061E2E52
R11 - 0000000000000020, R12 - 0000000003EE5C1F, R13 - 00000000061E0FF4
R14 - 0000000003E10D80, R15 - 00000000061E2F60
DS - 0000000000000030, ES - 0000000000000030, FS - 0000000000000030
GS - 0000000000000030, SS - 0000000000000030
CR0 - 0000000080010033, CR2 - 0000000000000000, CR3 - 0000000007C01000
CR4 - 0000000000000668, CR8 - 0000000000000000
DR0 - 0000000000000000, DR1 - 0000000000000000, DR2 - 0000000000000000
DR3 - 0000000000000000, DR6 - 00000000FFFF0FF0, DR7 - 0000000000000400
GDTR - 00000000079EEA98 0000000000000047, LDTR - 0000000000000000
IDTR - 0000000007598018 0000000000000FFF, TR - 0000000000000000
FXSAVE_STATE - 0000000007F0F4C0
Proposal here is to continue to free allocated memory for
exit boot services path but keep it for halt/reboot path
as it won't be much security concern here.
Introduced GRUB_LOADER_FLAG_EFI_KEEP_ALLOCATED_MEMORY
loader flag to be used by efi halt/reboot path.
Signed-off-by: Alexey Makhalov <amakhalov@vmware.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
When we exit grub, we don't free all the memory that we allocated earlier
for our heap region. This can cause problems with setups where you try
to descend the boot order using "exit" entries, such as PXE -> HD boot
scenarios.
Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The path returned by grub_efi_net_config has already been stripped for the
directory part extracted from cached bootp packet. We should just return the
result to avoild it be stripped again.
It fixed the problem that grub.efi as NBP image always looking for grub.cfg and
platform directory in upper folder rather than current one it gets loaded while
$prefix is empty. The behavior is inconsistent with other architecture and how
we would expect empty $prefix going to be in general.
The only exception to the general rule of empty $prefix is that when loaded
from platform directory itself, the platform part is stripped thus upper folder
is used for looking up files. It meets the case for how grub-mknetdir lay out
the files under tftp root directory, but also hide away this issue to be
identified as it appears to be just works.
Also fix possible memory leak by moving grub_efi_get_filename() call after
grub_efi_net_config().
We only support FDT files with EFI on arm and arm64 systems, not
on x86. So move the helper that finds a prepopulated FDT UUID
into its own file and only build it for architectures where it
also gets called.
Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Searching for a device tree that EFI passes to us via configuration tables
is nothing architecture specific. Move it into generic code.
Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The EFI version of grub_machine_get_bootlocation crops the boot image
name back to the last / in order to get a directory path. However, it
does not check that *name is actually set before calling grub_strrchr
to do this, and neither does grub_strrchr before dereferencing a NULL
pointer.
Parent function, grub_set_prefix_and_root, does check the pointer
before using.
starts with "(,", fill the drive containing the loaded image in
between those two characters, but expect that a full partition
specification including partition map names will follow.
