PEI variable implementation checks only the variable header signature for validity. This does not seem robust if system crash occurred during previous Reclaim() operation. If the crash occurred while FTW was rewriting the variable FV, the signature could be valid even though the rest of the FV isn't valid.
Solution: PEI variable and early phase(before FTW protocol ready) of DXE variable can check the FTW last write status provided by FaultTolerantWritePei and determine if all or partial variable data has been backed up in spare block, and then use the backed up data.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14455 6f19259b-4bc3-4df7-8a09-765794883524
The Variable PEI and RuntimeDxe drivers were using the attribute 'HeaderLength' of
EFI_FIRMWARE_VOLUME_HEADER without checking if a Firmware Volume Header was existing at
the base address.
In case the Firmware Volume Header does not exist or is corrupted, the attribute 'HeaderLength'
is a non valid value that can lead to a non valid physical address when accessing produces an
access error.
Signed-off-by: oliviermartin
Reviewed-by: rsun3
Reviewed-by: niruiyu
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12845 6f19259b-4bc3-4df7-8a09-765794883524