Replace "(UINT8 *)NewVariableData" with (UINT8 *)NewVariableData + Offset" to avoid the header of EFI_SIGNATURE_LIST being copied to the front of NewVariableData every time and update ListWalker when handling the current EFI_SIGNATURE_LIST finishes. Cc: Zhang Chao <chao.b.zhang@intel.com> Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: chenc2 <chen.a.chen@intel.com> Reviewed-by: Zhang Chao <chao.b.zhang@intel.com>