KVM: SEV: Pin source page for write when adding CPUID data for SNP guest
Get instant alerts when new vulnerabilities affect Linux - before attackers find them.
In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Pin source page for write when adding CPUID data for SNP guest When populating a guest_memfd instance with the initial CPUID data for an SNP guest, acquire a writable pin on the source page as KVM will write back the "correct" CPUID information if the userspace provided data is rejected by trusted firmware. Because KVM writes to the source page using a kernel mapping, pinning for read could result in KVM clobbering read-only memory. Note, well-behaved VMMs are unlikely to be affected, as CPUID information is almost always dynamically generated by userspace, i.e. it's unlikely for the CPUID information to be backed by a read-only mapping. [sean: rewrite shortlog and changelog, tag for stable@]
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
No remediation guidance has been written for this CVE yet. What the record does show:
Get alerted
Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.