发布于3月6日3月6日 Members Amazon Linux AMI: CVE-2022-48991: Security patch for kernel (ALAS-2023-1706) Severity 4 CVSS (AV:L/AC:M/Au:N/C:P/I:P/A:P) Published 03/17/2023 Created 01/25/2025 Added 01/23/2025 Modified 01/23/2025 Description In the Linux kernel, the following vulnerability has been resolved: mm/khugepaged: invoke MMU notifiers in shmem/file collapse paths Any codepath that zaps page table entries must invoke MMU notifiers to ensure that secondary MMUs (like KVM) don't keep accessing pages which aren't mapped anymore.Secondary MMUs don't hold their own references to pages that are mirrored over, so failing to notify them can lead to page use-after-free. I'm marking this as addressing an issue introduced in commit f3f0e1d2150b ("khugepaged: add support of collapse for tmpfs/shmem pages"), but most of the security impact of this only came in commit 27e1f8273113 ("khugepaged: enable collapse pmd for pte-mapped THP"), which actually omitted flushes for the removal of present PTEs, not just for the removal of empty page tables. Solution(s) amazon-linux-upgrade-kernel References ALAS-2023-1706 CVE-2022-48991
