CVE-2026-89920

In the Linux kernel, the following vulnerability has been resolved: KVM: s390: Fix memory corruption by not reinjecting CK machine checks Channel-subsystem damage machine checks are for the host channel subsystem. The guest channel subsystem is emulated in the userspace VMM. There is no point in forwarding such machine checks into the guest. This also simplifies the machine check reinjection and avoids kfree of a stack variable as reported by sashiko. There might be still machine checks that have the ck bit set with another bit (like instruction damage), mask out the CK bit in s390_backup_mcck_info(), like the CP and ED bits already are.

CVSS

No CVSS.

References

Link	Resource
https://git.kernel.org/stable/c/546dde823a36d7283dcf46127c2f3d093443860f
https://git.kernel.org/stable/c/6ee52d3af2a1bf70349cf3f860933c8d221e229a
https://git.kernel.org/stable/c/7077ec953996acc04b49d1dfc43df1c1a2a74395

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-16 11:17

Updated : 2026-09-16 11:17

NVD link : CVE-2026-89920

Mitre link : CVE-2026-89920

CVE.ORG link : CVE-2026-89920

JSON object : View

Products Affected

No product.

CWE

No CWE.

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