Original LRW mode has been semi-broken. http://grouper.ieee.org/groups/1619/email/msg00558.html
-> "dm-crypt... which leaks location of changed data in some unusual situations." => What exactly consists this leak and has it been fixed?
Last time I looked at dm-crypt it wasn't fixed.
If backing storage is at some remote server, and adversary can see ciphertext read/write traffic, he can get snapshots of old and new ciphertexts and extract some information from that.
-- BOFH excuse #28:
- Linux-crypto: cryptography in and on the Linux system Archive: http://mail.nl.linux.org/linux-crypto/