tyler.durden
/
audk
mirror of https://github.com/acidanthera/audk.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

MdePkg/BaseLib: Add new AsmLfence API 

REF:https://bugzilla.tianocore.org/show_bug.cgi?id=1193

This commit will add a new BaseLib API AsmLfence(). This API will perform
a serializing operation on all load-from-memory instructions that were
issued prior to the call of this function. Please note that this API is
only available on IA-32 and x64.

The purpose of adding this API is to mitigate of the [CVE-2017-5753]
Bounds Check Bypass issue when untrusted data are being processed within
SMM. More details can be referred at the 'Bounds check bypass mitigation'
section at the below link:

https://software.intel.com/security-software-guidance/insights/host-firmware-speculative-execution-side-channel-mitigation

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
This commit is contained in:
Hao Wu 2018-09-13 15:11:35 +08:00
parent 8285f42e58
commit 2ecd829972
4 changed files with 88 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
MdePkg/Include/Library/BaseLib.h
View File

@ -7696,6 +7696,19 @@ AsmWriteTr (
IN UINT16 Selector
);
/**
Performs a serializing operation on all load-from-memory instructions that
were issued prior the AsmLfence function.
Executes a LFENCE instruction. This function is only available on IA-32 and x64.
**/
VOID
EFIAPI
AsmLfence (
VOID
);
/**
Patch the immediate operand of an IA32 or X64 instruction such that the byte,
word, dword or qword operand is encoded at the end of the instruction's

2
MdePkg/Library/BaseLib/BaseLib.inf
View File

@ -68,6 +68,7 @@
[Sources.Ia32]
Ia32/WriteTr.nasm
Ia32/Lfence.nasm
Ia32/Wbinvd.c | MSFT
Ia32/WriteMm7.c | MSFT
@ -346,6 +347,7 @@
X64/EnableCache.nasm
X64/DisableCache.nasm
X64/WriteTr.nasm
X64/Lfence.nasm
X64/CpuBreakpoint.c | MSFT
X64/WriteMsr64.c | MSFT

36
MdePkg/Library/BaseLib/Ia32/Lfence.nasm Normal file
View File

@ -0,0 +1,36 @@
;------------------------------------------------------------------------------ ;
; Copyright (c) 2018, Intel Corporation. All rights reserved.<BR>
; This program and the accompanying materials
; are licensed and made available under the terms and conditions of the BSD License
; which accompanies this distribution. The full text of the license may be found at
; http://opensource.org/licenses/bsd-license.php.
;
; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
;
; Module Name:
;
; Lfence.nasm
;
; Abstract:
;
; Performs a serializing operation on all load-from-memory instructions that
; were issued prior to the call of this function.
;
; Notes:
;
;------------------------------------------------------------------------------
SECTION .text
;------------------------------------------------------------------------------
; VOID
; EFIAPI
; AsmLfence (
; VOID
; );
;------------------------------------------------------------------------------
global ASM_PFX(AsmLfence)
ASM_PFX(AsmLfence):
lfence
ret

37
MdePkg/Library/BaseLib/X64/Lfence.nasm Normal file
View File

@ -0,0 +1,37 @@
;------------------------------------------------------------------------------ ;
; Copyright (c) 2018, Intel Corporation. All rights reserved.<BR>
; This program and the accompanying materials
; are licensed and made available under the terms and conditions of the BSD License
; which accompanies this distribution. The full text of the license may be found at
; http://opensource.org/licenses/bsd-license.php.
;
; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
;
; Module Name:
;
; Lfence.nasm
;
; Abstract:
;
; Performs a serializing operation on all load-from-memory instructions that
; were issued prior to the call of this function.
;
; Notes:
;
;------------------------------------------------------------------------------
DEFAULT REL
SECTION .text
;------------------------------------------------------------------------------
; VOID
; EFIAPI
; AsmLfence (
; VOID
; );
;------------------------------------------------------------------------------
global ASM_PFX(AsmLfence)
ASM_PFX(AsmLfence):
lfence
ret