CVE-2026-89534: svcrdma: Clear sc_cm_id when ADDR_CHANGE replacement fails

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-11 · updated 2026-10-30

Description

In the Linux kernel, the following vulnerability has been resolved: svcrdma: Clear sc_cm_id when ADDR_CHANGE replacement fails When svc_rdma_listen_handler() handles RDMA_CM_EVENT_ADDR_CHANGE, it creates a replacement listener cm_id and returns 1, telling the CM core to destroy the old one. If the replacement allocation fails, sc_cm_id still points at the old cm_id that the CM core is about to destroy. Any subsequent dereference of sc_cm_id -- such as svc_rdma_detach()'s rdma_disconnect() call -- is a use-after-free. NULL sc_cm_id on the failure path and guard svc_rdma_detach()'s rdma_disconnect() call against NULL so that the listener can be torn down safely when the server shuts down.

Affected products

Linux: from 6.1.191 before 6.2; from 6.6.160 before 6.7 — fixed in 6.2, 6.7

How to fix

Upgrade to a fixed version: Linux 6.2, 6.7. Check the vendor advisory for mitigations.

References

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