Re: [PATCH v5 6/9] SecurityPkg/Tcg2Pei: Use Migrated FV Info Hob for calculating hash (CVE-2019-11098)

["Wang, Jian J" <jian.j.wang@intel.com>]

Reviewed-by: Jian J Wang <jian.j.wang@intel.com>

Regards,
Jian

> -----Original Message-----
> From: Jiang, Guomin <guomin.jiang@intel.com>
> Sent: Thursday, July 09, 2020 9:57 AM
> To: devel@edk2.groups.io
> Cc: Yao, Jiewen <jiewen.yao@intel.com>; Wang, Jian J <jian.j.wang@intel.com>;
> Zhang, Chao B <chao.b.zhang@intel.com>; Zhang, Qi1 <qi1.zhang@intel.com>;
> Kumar, Rahul1 <rahul1.kumar@intel.com>
> Subject: [PATCH v5 6/9] SecurityPkg/Tcg2Pei: Use Migrated FV Info Hob for
> calculating hash (CVE-2019-11098)
> 
> REF:https://bugzilla.tianocore.org/show_bug.cgi?id=1614
> 
> When we allocate pool to save rebased the PEIMs, the address will change
> randomly, therefore the hash will change and result PCR0 change as well.
> To avoid this, we save the raw PEIMs and use it to calculate hash.
> The Tcg2Pei calculate the hash and it use the Migrated FV Info.
> 
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Chao Zhang <chao.b.zhang@intel.com>
> Cc: Qi Zhang <qi1.zhang@intel.com>
> Cc: Rahul Kumar <rahul1.kumar@intel.com>
> Signed-off-by: Guomin Jiang <guomin.jiang@intel.com>
> ---
>  SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.inf |  1 +
>  SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.c   | 31 ++++++++++++++++++++++++++---
>  2 files changed, 29 insertions(+), 3 deletions(-)
> 
> diff --git a/SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.inf
> b/SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.inf
> index 3d361e8859e7..367df21eedaf 100644
> --- a/SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.inf
> +++ b/SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.inf
> @@ -63,6 +63,7 @@ [Guids]
>    gTcgEvent2EntryHobGuid                                               ## PRODUCES               ##
> HOB
>    gEfiTpmDeviceInstanceNoneGuid                                        ##
> SOMETIMES_PRODUCES     ## GUID       # TPM device identifier
>    gEfiTpmDeviceInstanceTpm12Guid                                       ##
> SOMETIMES_PRODUCES     ## GUID       # TPM device identifier
> +  gEdkiiMigratedFvInfoGuid                                             ##
> SOMETIMES_CONSUMES     ## HOB
> 
>  [Ppis]
>    gEfiPeiFirmwareVolumeInfoPpiGuid                                     ##
> SOMETIMES_CONSUMES     ## NOTIFY
> diff --git a/SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.c
> b/SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.c
> index 4852d8690617..651a60c1f0e2 100644
> --- a/SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.c
> +++ b/SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.c
> @@ -21,6 +21,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
>  #include <Guid/TcgEventHob.h>
>  #include <Guid/MeasuredFvHob.h>
>  #include <Guid/TpmInstance.h>
> +#include <Guid/MigratedFvInfo.h>
> 
>  #include <Library/DebugLib.h>
>  #include <Library/BaseMemoryLib.h>
> @@ -536,6 +537,10 @@ MeasureFvImage (
>    EDKII_PEI_FIRMWARE_VOLUME_INFO_PREHASHED_FV_PPI
> *PrehashedFvPpi;
>    HASH_INFO                                             *PreHashInfo;
>    UINT32                                                HashAlgoMask;
> +  EFI_PHYSICAL_ADDRESS                                  FvOrgBase;
> +  EFI_PHYSICAL_ADDRESS                                  FvDataBase;
> +  EFI_PEI_HOB_POINTERS                                  Hob;
> +  EDKII_MIGRATED_FV_INFO                                *MigratedFvInfo;
> 
>    //
>    // Check Excluded FV list
> @@ -621,6 +626,26 @@ MeasureFvImage (
>      Instance++;
>    } while (!EFI_ERROR(Status));
> 
> +  //
> +  // Search the matched migration FV info
> +  //
> +  FvOrgBase  = FvBase;
> +  FvDataBase = FvBase;
> +  Hob.Raw  = GetFirstGuidHob (&gEdkiiMigratedFvInfoGuid);
> +  while (Hob.Raw != NULL) {
> +    MigratedFvInfo = GET_GUID_HOB_DATA (Hob);
> +    if ((MigratedFvInfo->FvNewBase == (UINT32) FvBase) && (MigratedFvInfo-
> >FvLength == (UINT32) FvLength)) {
> +      //
> +      // Found the migrated FV info
> +      //
> +      FvOrgBase  = (EFI_PHYSICAL_ADDRESS) (UINTN) MigratedFvInfo-
> >FvOrgBase;
> +      FvDataBase = (EFI_PHYSICAL_ADDRESS) (UINTN) MigratedFvInfo-
> >FvDataBase;
> +      break;
> +    }
> +    Hob.Raw = GET_NEXT_HOB (Hob);
> +    Hob.Raw = GetNextGuidHob (&gEdkiiMigratedFvInfoGuid, Hob.Raw);
> +  }
> +
>    //
>    // Init the log event for FV measurement
>    //
> @@ -631,13 +656,13 @@ MeasureFvImage (
>      if (FvName != NULL) {
>        AsciiSPrint ((CHAR8 *)FvBlob2.BlobDescription,
> sizeof(FvBlob2.BlobDescription), "Fv(%g)", FvName);
>      }
> -    FvBlob2.BlobBase      = FvBase;
> +    FvBlob2.BlobBase      = FvOrgBase;
>      FvBlob2.BlobLength    = FvLength;
>      TcgEventHdr.EventType = EV_EFI_PLATFORM_FIRMWARE_BLOB2;
>      TcgEventHdr.EventSize = sizeof (FvBlob2);
>      EventData             = &FvBlob2;
>    } else {
> -    FvBlob.BlobBase       = FvBase;
> +    FvBlob.BlobBase       = FvOrgBase;
>      FvBlob.BlobLength     = FvLength;
>      TcgEventHdr.PCRIndex  = 0;
>      TcgEventHdr.EventType = EV_EFI_PLATFORM_FIRMWARE_BLOB;
> @@ -672,7 +697,7 @@ MeasureFvImage (
>      //
>      Status = HashLogExtendEvent (
>                 0,
> -               (UINT8*) (UINTN) FvBase, // HashData
> +               (UINT8*) (UINTN) FvDataBase, // HashData
>                 (UINTN) FvLength,        // HashDataLen
>                 &TcgEventHdr,            // EventHdr
>                 EventData                // EventData
> --
> 2.25.1.windows.1