Use OPENSSL_cleanse() with care if the memory is a mapping of a file.
If the storage controller uses write compression, then its possible
that sensitive tail bytes will survive zeroization because the block of
-zeros will be compressed. If the storage controller uses wear levelling,
+zeros will be compressed. If the storage controller uses wear leveling,
then the old sensitive data will not be overwritten; rather, a block of
0's will be written at a new physical location.