CVE-2026-63939 KVM: SEV: Compute the correct max length of the in-GHCB scratch area

In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Compute the correct max length of the in-GHCB scratch area When setting the length of the GHCB scratch area, and the area is in the GHCB shared buffer, set the effective length of the scratch area to the max possible si...

CVE-2026-63938

The vulnerability CVE-2026-63938 affects the Linux kernel KVM SEV path, specifically PSC processing. The issue arises when validating PSC requests: the PSC buffer must be checked against the effective size of the scratch area, which may be smaller than the maximum if a guest supplies a pointer no...