GHSA-H444-6J9X-P8VH mv: symlinks expanded during cross-device move (resource exhaustion / data duplication)

When moving directories across filesystems, uutils mv dereferences symlinks inside the tree, copying their targets as real files/dirs instead of preserving the symlinks. GNU preserves symlinks by default. E.g. a etclink - /etc inside the source becomes a full copy of /etc at the destination...