CVE-2026-64310
CVE-2026-64310CVE-2026-64310
Description
In the Linux kernel, the following vulnerability has been resolved:
crypto: ccp - Do not initialize SNP for SEV ioctls
Sashiko notes:
> if SEV initialization fails and KVM is actively running normal VMs, could a
> userspace process trigger this code path via /dev/sev ioctls (e.g.,
> SEV_PDH_GEN) and zero out MSR_VM_HSAVE_PA globally? Would the next VMRUN
> execution for an active VM trigger a general protection fault and crash the
> host?
sev_move_to_init_state() is called for ioctls requiring only SEV firmware:
SEV_PEK_GEN, SEV_PDH_GEN, SEV_PEK_CSR, SEV_PEK_CERT_IMPORT, and
SEV_PDH_CERT_EXPORT. After the firmware command, it does SEV_SHUTDOWN on
the SEV firmware. Since these commands do not require SNP to be
initialized, skip it by calling __sev_platform_init_locked() which only
initializes the SEV firmware. This way SNP is not Initialized at all, and
HSAVE_PA is not cleared.
The previous code saved any SEV initialization firmware error to
init_args.error and then threw it away a
Scoring
| Last modified | 2026-07-25 |