CVE-2026-97593

In the Linux kernel, the following vulnerability has been resolved: iommu/s390: Fix NULL dereference in iova_to_phys() with ZPCI_TABLE_TYPE_RFX When using a 5-level translation table via ZPCI_TABLE_TYPE_RFX get_rso_from_iova() returns NULL when the region-first entry is invalid. Yet in get_rto_from_iova() the region-second origin rso is not checked to be non-NULL before accessing rso[rsx] leading to a NULL pointer dereference instead of a NULL return when iova_to_phys() is called on a unmapped IOVA. Fix this by adding the missing NULL check.

• https://git.kernel.org/stable/c/20db6573301e66cd65ebf6c130b6563c69374d9d
• https://git.kernel.org/stable/c/41b5e0ce6801bf04d8fd3bca46e8c393349ebd5c
• https://git.kernel.org/stable/c/d0502ed0a1aae97e2ab7a21545903ba612d9f02e