CVE-2026-98653

In the Linux kernel, the following vulnerability has been resolved: KVM: s390: Fix _gaccess_shadow_fault() 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. dat_entry_walk() will not find any leaf entry and return with -ENOENT, which will erroneously be propagated all the way to userspace. Fix by manually calling gmap_link() on the memory of the nested guest that is being shadowed if the mapping was not already present.

• https://git.kernel.org/stable/c/94c43c7df46433ed4d1e18f13770b019ba977bd8
• https://git.kernel.org/stable/c/faff4c8ff3dbec6d71b89dd281a0d17c4478fa44