Shell will ASSERT when doing the following operation: "" Shell> mv fs2:\file1 fs2:\file2 "" This patch add NULL pointer check to fix this issue. Fixes: https://github.com/tianocore/edk2/issues/76 Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Qiu Shumin <shumin.qiu@intel.com> Reviewed-by: Jaben Carsey <jaben.carsey@intel.com> Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>