[seiji]

Yes, exactly true. Some libraries (like innodb) actually checksum all contents in memory to self-detect when corruption is happening. Most applications and libraries trust system memory too much and can read corrupted data at any given time.

Another fun way to get corrupted memory is to have some data swapped to disk, but have disk corruption, then have the corrupt disk data restored to memory. Bam. Instant invalid data in memory, but not caused by memory.

Many hashes are fast these days and should be used as checksums in more places since ECC isn't as common as it should be (and ECC doesn't detect all errors anyway).