2024-01-30 15:01:08
redhat
PUBLISHED
A flaw was found in the Linux kernels memory deduplication mechanism. The max page sharing of Kernel Samepage Merging (KSM), added in Linux kernel version 4.4.0-96.119, can create a side channel. When the attacker and the victim share the same host and the default setting of KSM is "max page sharing=256", it is possible for the attacker to time the unmap to merge with the victims page. The unmapping time depends on whether it merges with the victims page and additional physical pages are created beyond the KSMs "max page share". Through these operations, the attacker can leak the victims page.