CVE-2023-46837

Arm provides multiple helpers to clean & invalidate the cache for a given
region. This is, for instance, used when allocating guest memory to ensure
any writes (such as the ones during scrubbing) have reached memory before
handing over the page to a guest. Unfortunately, the arithmetics in the
helpers can overflow and would then result to skip the cache
cleaning/invalidation. Therefore there is no guarantee when all the writes
will reach the memory. This undefined behavior was meant to be addressed by
XSA-437, but the approach was not sufficient.

Notes