linux/arch/x86/platform
Tom Lendacky 1ff2fc0286 x86/sme: Explicitly map new EFI memmap table as encrypted
Reserving memory using efi_mem_reserve() calls into the x86
efi_arch_mem_reserve() function. This function will insert a new EFI
memory descriptor into the EFI memory map representing the area of
memory to be reserved and marking it as EFI runtime memory. As part
of adding this new entry, a new EFI memory map is allocated and mapped.
The mapping is where a problem can occur. This new memory map is mapped
using early_memremap() and generally mapped encrypted, unless the new
memory for the mapping happens to come from an area of memory that is
marked as EFI_BOOT_SERVICES_DATA memory. In this case, the new memory will
be mapped unencrypted. However, during replacement of the old memory map,
efi_mem_type() is disabled, so the new memory map will now be long-term
mapped encrypted (in efi.memmap), resulting in the map containing invalid
data and causing the kernel boot to crash.

Since it is known that the area will be mapped encrypted going forward,
explicitly map the new memory map as encrypted using early_memremap_prot().

Cc: <stable@vger.kernel.org> # 4.14.x
Fixes: 8f716c9b5f ("x86/mm: Add support to access boot related data in the clear")
Link: https://lore.kernel.org/all/ebf1eb2940405438a09d51d121ec0d02c8755558.1634752931.git.thomas.lendacky@amd.com/
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
[ardb: incorporate Kconfig fix by Arnd]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2021-12-05 16:44:52 +01:00
..
atom x86/platform: Convert to new CPU match macros 2020-03-24 21:29:38 +01:00
ce4100 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441 2019-06-05 17:37:17 +02:00
efi x86/sme: Explicitly map new EFI memmap table as encrypted 2021-12-05 16:44:52 +01:00
geode x86/platform/geode: Convert alix LED to GPIO machine descriptor 2021-01-15 18:55:53 +01:00
intel x86: Fix various typos in comments 2021-03-18 15:31:53 +01:00
intel-mid platform-drivers-x86 for v5.12-1 2021-02-22 08:50:01 -08:00
intel-quark x86/platform/intel/quark: Fix incorrect kernel-doc comment syntax in files 2021-04-10 13:59:25 +02:00
iris module: remove never implemented MODULE_SUPPORTED_DEVICE 2021-03-17 13:16:18 -07:00
olpc x86/platform/olpc: Correct ifdef symbol to intended CONFIG_OLPC_XO15_SCI 2021-10-06 18:46:06 +02:00
pvh x86/PVH: adjust function/data placement 2021-10-05 08:36:17 +02:00
scx200 treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
ts5500 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
uv A bunch of SGI UV improvements, fixes and cleanups. 2021-04-26 09:34:19 -07:00
Makefile Simple Firmware Interface (SFI) support removal for v5.12-rc1 2021-02-24 10:35:29 -08:00