CyberRota Analysis
AI-GeneratedA vulnerability in the Linux kernel affects the KVM module for arm64 architectures, where it improperly maps the L1 VNCR by relying solely on guest stage-1 permissions, potentially allowing unauthorized write access to read-only memory. This can lead to privilege escalation and data integrity issues if exploited. Organizations using Linux with KVM on arm64 should prioritize addressing this vulnerability to mitigate risks associated with unauthorized memory access.
Original NVD Description
In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: nv: Respect read-only PFN when mapping L1 VNCR KVM currently maps the L1 VNCR into the host stage-1 by relying entirely on the permissions of the guest stage-1. At the same time, it is entirely possible that the backing PFN is read-only (e.g. RO memslot), meaning that the L1 VNCR should use at most a read-only mapping. Cache the writability of the PFN in the VNCR TLB and use it to constrain the resulting fixmap permissions. Promote VNCR permission faults to an SEA in the case where the guest attempts to write to a read-only endpoint. Conveniently, this also plugs a page leak found by Sashiko [*] resulting from the early return for a read-only PFN.