[PATCH EDK2 v1 1/1] ArmPlatformPkg/Drivers/NorFlashDxe:avoid index out of bound

["wenyi,xie" <xiewenyi2@huawei.com>]

The size of array BlockMap is 1 in struct FirmwareVolumeHeader, but in
function InitializeFvAndVariableStoreHeaders, BlockMap[1] is been written.
The memory of BlockMap[1] is already allocated, so the code is OK. But
it is better to use a new point to assign this memory.

Cc: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Signed-off-by: Wenyi Xie <xiewenyi2@huawei.com>
---
 ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashFvb.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashFvb.c b/ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashFvb.c
index 0767581308d2..2130e2e76344 100644
--- a/ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashFvb.c
+++ b/ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashFvb.c
@@ -47,6 +47,7 @@ InitializeFvAndVariableStoreHeaders (
   VOID                        *Headers;
   UINTN                       HeadersLength;
   EFI_FIRMWARE_VOLUME_HEADER  *FirmwareVolumeHeader;
+  EFI_FV_BLOCK_MAP_ENTRY      *BlockMapEntry;
   VARIABLE_STORE_HEADER       *VariableStoreHeader;
   UINT32                      NvStorageFtwSpareSize;
   UINT32                      NvStorageFtwWorkingSize;
@@ -151,10 +152,15 @@ InitializeFvAndVariableStoreHeaders (
   FirmwareVolumeHeader->Revision              = EFI_FVH_REVISION;
   FirmwareVolumeHeader->BlockMap[0].NumBlocks = Instance->Media.LastBlock + 1;
   FirmwareVolumeHeader->BlockMap[0].Length    = Instance->Media.BlockSize;
-  FirmwareVolumeHeader->BlockMap[1].NumBlocks = 0;
-  FirmwareVolumeHeader->BlockMap[1].Length    = 0;
   FirmwareVolumeHeader->Checksum              = CalculateCheckSum16 ((UINT16 *)FirmwareVolumeHeader, FirmwareVolumeHeader->HeaderLength);
 
+  //
+  // EFI_FV_BLOCK_MAP_ENTRY
+  //
+  BlockMapEntry            = (EFI_FV_BLOCK_MAP_ENTRY *)((UINTN)Headers + sizeof (EFI_FIRMWARE_VOLUME_HEADER));
+  BlockMapEntry->NumBlocks = 0;
+  BlockMapEntry->Length    = 0;
+
   //
   // VARIABLE_STORE_HEADER
   //
-- 
2.20.1.windows.1