* [PATCH] UefiCpuPkg/MpInitLib: Move checksum part for valid microcode data
@ 2019-06-24 6:14 Gao, Zhichao
2019-06-24 20:33 ` Laszlo Ersek
0 siblings, 1 reply; 2+ messages in thread
From: Gao, Zhichao @ 2019-06-24 6:14 UTC (permalink / raw)
To: devel; +Cc: Eric Dong, Ray Ni, Laszlo Ersek, Liming Gao
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1934
Originally, the checksum part would done before verfiy the microcode
data. Which meas the checksum would be done for a meaningless data.
It would cause a incorrect TotalSize (the size of microcode data),
then incorrect checksum and incorrect pointer increasing would happen.
To fix this, move the checksum part 1 section in
'if (MicrocodeEntryPoint->HeaderVersion == 0x1)' section for a valid
microcode data.
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Liming Gao <liming.gao@intel.com>
Signed-off-by: Zhichao Gao <zhichao.gao@intel.com>
---
UefiCpuPkg/Library/MpInitLib/Microcode.c | 52 ++++++++++++------------
1 file changed, 26 insertions(+), 26 deletions(-)
diff --git a/UefiCpuPkg/Library/MpInitLib/Microcode.c b/UefiCpuPkg/Library/MpInitLib/Microcode.c
index 4763dcfebe..f1a42f2d4e 100644
--- a/UefiCpuPkg/Library/MpInitLib/Microcode.c
+++ b/UefiCpuPkg/Library/MpInitLib/Microcode.c
@@ -1,7 +1,7 @@
/** @file
Implementation of loading microcode on processors.
- Copyright (c) 2015 - 2018, Intel Corporation. All rights reserved.<BR>
+ Copyright (c) 2015 - 2019, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
@@ -160,34 +160,34 @@ MicrocodeDetect (
//
CorrectMicrocode = FALSE;
- if (MicrocodeEntryPoint->DataSize == 0) {
- TotalSize = sizeof (CPU_MICROCODE_HEADER) + 2000;
- } else {
- TotalSize = sizeof (CPU_MICROCODE_HEADER) + MicrocodeEntryPoint->DataSize;
- }
+ if (MicrocodeEntryPoint->HeaderVersion == 0x1) {
+ if (MicrocodeEntryPoint->DataSize == 0) {
+ TotalSize = sizeof (CPU_MICROCODE_HEADER) + 2000;
+ } else {
+ TotalSize = sizeof (CPU_MICROCODE_HEADER) + MicrocodeEntryPoint->DataSize;
+ }
- ///
- /// Check overflow and whether TotalSize is aligned with 4 bytes.
- ///
- if ( ((UINTN)MicrocodeEntryPoint + TotalSize) > MicrocodeEnd ||
- (TotalSize & 0x3) != 0
- ) {
- MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (((UINTN) MicrocodeEntryPoint) + SIZE_1KB);
- continue;
- }
+ ///
+ /// Check overflow and whether TotalSize is aligned with 4 bytes.
+ ///
+ if ( ((UINTN)MicrocodeEntryPoint + TotalSize) > MicrocodeEnd ||
+ (TotalSize & 0x3) != 0
+ ) {
+ MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (((UINTN) MicrocodeEntryPoint) + SIZE_1KB);
+ continue;
+ }
- //
- // Save an in-complete CheckSum32 from CheckSum Part1 for common parts.
- //
- InCompleteCheckSum32 = CalculateSum32 (
- (UINT32 *) MicrocodeEntryPoint,
- TotalSize
- );
- InCompleteCheckSum32 -= MicrocodeEntryPoint->ProcessorSignature.Uint32;
- InCompleteCheckSum32 -= MicrocodeEntryPoint->ProcessorFlags;
- InCompleteCheckSum32 -= MicrocodeEntryPoint->Checksum;
+ //
+ // Save an in-complete CheckSum32 from CheckSum Part1 for common parts.
+ //
+ InCompleteCheckSum32 = CalculateSum32 (
+ (UINT32 *) MicrocodeEntryPoint,
+ TotalSize
+ );
+ InCompleteCheckSum32 -= MicrocodeEntryPoint->ProcessorSignature.Uint32;
+ InCompleteCheckSum32 -= MicrocodeEntryPoint->ProcessorFlags;
+ InCompleteCheckSum32 -= MicrocodeEntryPoint->Checksum;
- if (MicrocodeEntryPoint->HeaderVersion == 0x1) {
//
// It is the microcode header. It is not the padding data between microcode patches
// because the padding data should not include 0x00000001 and it should be the repeated
--
2.21.0.windows.1
^ permalink raw reply related [flat|nested] 2+ messages in thread* Re: [PATCH] UefiCpuPkg/MpInitLib: Move checksum part for valid microcode data
2019-06-24 6:14 [PATCH] UefiCpuPkg/MpInitLib: Move checksum part for valid microcode data Gao, Zhichao
@ 2019-06-24 20:33 ` Laszlo Ersek
0 siblings, 0 replies; 2+ messages in thread
From: Laszlo Ersek @ 2019-06-24 20:33 UTC (permalink / raw)
To: Zhichao Gao, devel; +Cc: Eric Dong, Ray Ni, Liming Gao
On 06/24/19 08:14, Zhichao Gao wrote:
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1934
>
> Originally, the checksum part would done before verfiy the microcode
> data. Which meas the checksum would be done for a meaningless data.
> It would cause a incorrect TotalSize (the size of microcode data),
> then incorrect checksum and incorrect pointer increasing would happen.
> To fix this, move the checksum part 1 section in
> 'if (MicrocodeEntryPoint->HeaderVersion == 0x1)' section for a valid
> microcode data.
>
> Cc: Eric Dong <eric.dong@intel.com>
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Cc: Liming Gao <liming.gao@intel.com>
> Signed-off-by: Zhichao Gao <zhichao.gao@intel.com>
> ---
> UefiCpuPkg/Library/MpInitLib/Microcode.c | 52 ++++++++++++------------
> 1 file changed, 26 insertions(+), 26 deletions(-)
I'll defer on this patch to the (other) UefiCpuPkg reviewers /
maintainers. OVMF inherits the default zero value for
"PcdCpuMicrocodePatchRegionSize", from "UefiCpuPkg.dec". Therefore the
first check in MicrocodeDetect() evaluates to TRUE, and the function
exits immediately, in OVMF.
Thanks
Laszlo
> diff --git a/UefiCpuPkg/Library/MpInitLib/Microcode.c b/UefiCpuPkg/Library/MpInitLib/Microcode.c
> index 4763dcfebe..f1a42f2d4e 100644
> --- a/UefiCpuPkg/Library/MpInitLib/Microcode.c
> +++ b/UefiCpuPkg/Library/MpInitLib/Microcode.c
> @@ -1,7 +1,7 @@
> /** @file
> Implementation of loading microcode on processors.
>
> - Copyright (c) 2015 - 2018, Intel Corporation. All rights reserved.<BR>
> + Copyright (c) 2015 - 2019, Intel Corporation. All rights reserved.<BR>
> SPDX-License-Identifier: BSD-2-Clause-Patent
>
> **/
> @@ -160,34 +160,34 @@ MicrocodeDetect (
> //
> CorrectMicrocode = FALSE;
>
> - if (MicrocodeEntryPoint->DataSize == 0) {
> - TotalSize = sizeof (CPU_MICROCODE_HEADER) + 2000;
> - } else {
> - TotalSize = sizeof (CPU_MICROCODE_HEADER) + MicrocodeEntryPoint->DataSize;
> - }
> + if (MicrocodeEntryPoint->HeaderVersion == 0x1) {
> + if (MicrocodeEntryPoint->DataSize == 0) {
> + TotalSize = sizeof (CPU_MICROCODE_HEADER) + 2000;
> + } else {
> + TotalSize = sizeof (CPU_MICROCODE_HEADER) + MicrocodeEntryPoint->DataSize;
> + }
>
> - ///
> - /// Check overflow and whether TotalSize is aligned with 4 bytes.
> - ///
> - if ( ((UINTN)MicrocodeEntryPoint + TotalSize) > MicrocodeEnd ||
> - (TotalSize & 0x3) != 0
> - ) {
> - MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (((UINTN) MicrocodeEntryPoint) + SIZE_1KB);
> - continue;
> - }
> + ///
> + /// Check overflow and whether TotalSize is aligned with 4 bytes.
> + ///
> + if ( ((UINTN)MicrocodeEntryPoint + TotalSize) > MicrocodeEnd ||
> + (TotalSize & 0x3) != 0
> + ) {
> + MicrocodeEntryPoint = (CPU_MICROCODE_HEADER *) (((UINTN) MicrocodeEntryPoint) + SIZE_1KB);
> + continue;
> + }
>
> - //
> - // Save an in-complete CheckSum32 from CheckSum Part1 for common parts.
> - //
> - InCompleteCheckSum32 = CalculateSum32 (
> - (UINT32 *) MicrocodeEntryPoint,
> - TotalSize
> - );
> - InCompleteCheckSum32 -= MicrocodeEntryPoint->ProcessorSignature.Uint32;
> - InCompleteCheckSum32 -= MicrocodeEntryPoint->ProcessorFlags;
> - InCompleteCheckSum32 -= MicrocodeEntryPoint->Checksum;
> + //
> + // Save an in-complete CheckSum32 from CheckSum Part1 for common parts.
> + //
> + InCompleteCheckSum32 = CalculateSum32 (
> + (UINT32 *) MicrocodeEntryPoint,
> + TotalSize
> + );
> + InCompleteCheckSum32 -= MicrocodeEntryPoint->ProcessorSignature.Uint32;
> + InCompleteCheckSum32 -= MicrocodeEntryPoint->ProcessorFlags;
> + InCompleteCheckSum32 -= MicrocodeEntryPoint->Checksum;
>
> - if (MicrocodeEntryPoint->HeaderVersion == 0x1) {
> //
> // It is the microcode header. It is not the padding data between microcode patches
> // because the padding data should not include 0x00000001 and it should be the repeated
>
^ permalink raw reply [flat|nested] 2+ messages in thread
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2019-06-24 6:14 [PATCH] UefiCpuPkg/MpInitLib: Move checksum part for valid microcode data Gao, Zhichao
2019-06-24 20:33 ` Laszlo Ersek
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