Re: [PATCH] IntelSiliconPkg MicrocodeUpdateDxe: Fix (ExtendedTableLength & 0x3)!=0

["Yao, Jiewen" <jiewen.yao@intel.com>]

Reviewed-by: Jiewen.yao@intel.com

> -----Original Message-----
> From: Zeng, Star
> Sent: Thursday, December 21, 2017 10:35 AM
> To: edk2-devel@lists.01.org
> Cc: Zeng, Star <star.zeng@intel.com>; Yao, Jiewen <jiewen.yao@intel.com>;
> Chaganty, Rangasai V <rangasai.v.chaganty@intel.com>
> Subject: [PATCH] IntelSiliconPkg MicrocodeUpdateDxe: Fix (ExtendedTableLength
> & 0x3)!=0
> 
> The first 48 bytes contain the microcode update header.
> DataSize must be a multiple of DWORDs.
> TotalSize is always a multiple of 1024.
> Both size of CPU_MICROCODE_EXTENDED_TABLE_HEADER and
> CPU_MICROCODE_EXTENDED_TABLE are multiple of DWORDs.
> 
> So (ExtendedTableLength & 0x3)!=0 should be
> (ExtendedTableLength & 0x3)==0.
> 
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Rangasai V Chaganty <rangasai.v.chaganty@intel.com>
> Contributed-under: TianoCore Contribution Agreement 1.1
> Signed-off-by: Star Zeng <star.zeng@intel.com>
> ---
>  IntelSiliconPkg/Feature/Capsule/MicrocodeUpdateDxe/MicrocodeUpdate.c | 4
> ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git
> a/IntelSiliconPkg/Feature/Capsule/MicrocodeUpdateDxe/MicrocodeUpdate.c
> b/IntelSiliconPkg/Feature/Capsule/MicrocodeUpdateDxe/MicrocodeUpdate.c
> index 4e8f1d5fd8a8..b99221c9696d 100644
> --- a/IntelSiliconPkg/Feature/Capsule/MicrocodeUpdateDxe/MicrocodeUpdate.c
> +++
> b/IntelSiliconPkg/Feature/Capsule/MicrocodeUpdateDxe/MicrocodeUpdate.c
> @@ -8,7 +8,7 @@
> 
>    MicrocodeWrite() and VerifyMicrocode() will receive untrusted input and do
> basic validation.
> 
> -  Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
> +  Copyright (c) 2016 - 2017, 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
> @@ -494,7 +494,7 @@ VerifyMicrocode (
>        //
>        // Calculate Extended Checksum
>        //
> -      if ((ExtendedTableLength >
> sizeof(CPU_MICROCODE_EXTENDED_TABLE_HEADER)) &&
> ((ExtendedTableLength & 0x3) != 0)) {
> +      if ((ExtendedTableLength >
> sizeof(CPU_MICROCODE_EXTENDED_TABLE_HEADER)) &&
> ((ExtendedTableLength & 0x3) == 0)) {
>          CheckSum32 = CalculateSum32((UINT32 *)ExtendedTableHeader,
> ExtendedTableLength);
>          if (CheckSum32 == 0) {
>            //
> --
> 2.7.0.windows.1