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CVE-2025-39939

In the Linux kernel, the following vulnerability has been resolved: iommu/s390: Fix memory corruption when using identity domain zpci_get_iommu_ctrs() returns counter…

Published Oct 4, 2025 · updated Oct 15, 2026 · linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: iommu/s390: Fix memory corruption when using identity domain zpci_get_iommu_ctrs() returns counter information to be reported as part of device statistics; these counters are stored as part of the s390_domain. The problem, however, is that the identity domain is not backed by an s390_domain and so the conversion via to_s390_domain() yields a bad address that is zero'd initially and read on-demand later via a sysfs read. These counters aren't necessary for the identity domain; just return NULL in this case. This issue was discovered via KASAN with reports that look like: BUG: KASAN: global-out-of-bounds in zpci_fmb_enable_device when using the identity domain for a device on s390.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Oct 4, 2025 · NIST NVD

    Detected

    In the Linux kernel, the following vulnerability has been resolved: iommu/s390: Fix memory corruption when using identity domain zpci_get_iommu_ctrs() returns counter information to be reported as part of device statistics; these counters are stored as part of the s390_domain. The problem, however, is that the identity domain is not backed by an s390_domain and so the conversion via to_s390_domain

  2. Oct 15, 2026 · NIST NVD

    Updated

    In the Linux kernel, the following vulnerability has been resolved: iommu/s390: Fix memory corruption when using identity domain zpci_get_iommu_ctrs() returns counter information to be reported as part of device statistics; these counters are stored as part of the s390_domain. The problem, however, is that the identity domain is not backed by an s390_domain and so the conversion via to_s390_domain

Affected

  • cpe linux/linux kernelversion unspecified
  • cpe linux/linux kernel6.17

Sources

  • CVE.orgVulnerability recordCVE-2025-39939

    Official CVE identifier

    cve.org
  • NIST NVDVulnerability recordCVE-2025-39939

    In the Linux kernel, the following vulnerability has been resolved: iommu/s390: Fix memory corruption when using identity domain zpci_get_iommu_ctrs() returns counter information to be reported as part of device statistics; these counters are stored as part of the s390_domain.

    nvd.nist.gov

References