UBUNTU-CVE-2026-98653: Medium severity ubuntu/linux-hwe-edge vulnerability
In the Linux kernel, the following vulnerability has been resolved: KVM: s390: Fix gaccessshadowfault() In some circumstances, it is possible that the page of nested guest memory that is being shadowed is not present at all in the parent guest gmap. datentrywalk() will not find any leaf entry and return with -ENOENT, which will erroneously be propagated all the way to userspace. Fix by manually calling gmaplink() on the memory of the nested guest that is being shadowed if the mapping was not already present.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Compensating control
Manually call gmap_link() on the memory of the nested guest being shadowed when the mapping is not already present.