{"id":"CVE-2025-39939","summary":"iommu/s390: Fix memory corruption when using identity domain","details":"In the Linux kernel, the following vulnerability has been resolved:\n\niommu/s390: Fix memory corruption when using identity domain\n\nzpci_get_iommu_ctrs() returns counter information to be reported as part\nof device statistics; these counters are stored as part of the s390_domain.\nThe problem, however, is that the identity domain is not backed by an\ns390_domain and so the conversion via to_s390_domain() yields a bad address\nthat is zero'd initially and read on-demand later via a sysfs read.\nThese counters aren't necessary for the identity domain; just return NULL\nin this case.\n\nThis issue was discovered via KASAN with reports that look like:\nBUG: KASAN: global-out-of-bounds in zpci_fmb_enable_device\nwhen using the identity domain for a device on s390.","modified":"2026-09-14T18:27:01.773246478Z","published":"2025-10-04T07:31:02.521Z","related":["SUSE-SU-2026:4120-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/39xxx/CVE-2025-39939.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/17a58caf3863163c4a84a218a9649be2c8061443"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b3506e9bcc777ed6af2ab631c86a9990ed97b474"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/39xxx/CVE-2025-39939.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-39939"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"64af12c6ec3afd7d44bc8b2044eee59f98059087"},{"fixed":"17a58caf3863163c4a84a218a9649be2c8061443"},{"fixed":"b3506e9bcc777ed6af2ab631c86a9990ed97b474"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-39939.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.15.0"},{"fixed":"6.16.9"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-39939.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}