ArmPkg/NorFlashDxe : Fix the check of flash addresses

Fix the check to prevent any reading past the end of the nor flash.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Reviewed-by: Olivier Martin <olivier.martin@arm.com>



git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16655 6f19259b-4bc3-4df7-8a09-765794883524

1 files changed, 2 insertions, 11 deletions

diff --git a/ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashDxe.c b/ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashDxe.c
index 2f828ec869..3abbe5cb32 100644
--- a/ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashDxe.c
+++ b/ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashDxe.c
@@ -805,8 +805,7 @@ NorFlashRead (
   OUT VOID                *Buffer

   )

 {

-  UINT32              NumBlocks;

-  UINTN               StartAddress;

+  UINTN  StartAddress;

 

   // The buffer must be valid

   if (Buffer == NULL) {

@@ -818,15 +817,7 @@ NorFlashRead (
     return EFI_SUCCESS;

   }

 

-  // All blocks must be within the device

-  NumBlocks = ((UINT32)BufferSizeInBytes) / Instance->Media.BlockSize ;

-

-  if ((Lba + NumBlocks) > (Instance->Media.LastBlock + 1)) {

-    DEBUG ((EFI_D_ERROR, "NorFlashRead: ERROR - Read will exceed last block\n"));

-    return EFI_INVALID_PARAMETER;

-  }

-

-  if (Offset + BufferSizeInBytes >= Instance->Size) {

+  if (((Lba * Instance->Media.BlockSize) + Offset + BufferSizeInBytes) > Instance->Size) {

     DEBUG ((EFI_D_ERROR, "NorFlashRead: ERROR - Read will exceed device size.\n"));

     return EFI_INVALID_PARAMETER;

   }