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 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.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/17a58caf3863163c4a84a218a9649be2c8061443	Patch
https://git.kernel.org/stable/c/b3506e9bcc777ed6af2ab631c86a9990ed97b474	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc1::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc2::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc3::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc4::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc5::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc6::::::

History

No history.

Information

Published : 2025-10-04 08:15

Updated : 2026-01-27 19:54

NVD link : CVE-2025-39939

Mitre link : CVE-2025-39939

CVE.ORG link : CVE-2025-39939

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-787

Out-of-bounds Write

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