Race Condition in Linux Kernel Affecting Virtual Function CCS Management

CVE-2026-68384

What is CVE-2026-68384?

A vulnerability in the Linux kernel related to the management of Virtual Function (VF) Cache Coherent Shared (CCS) batch buffers has been identified. This issue arises from the improper timing of attaching and detaching these buffers during memory operations, which can lead to data inconsistencies. Specifically, the operations are performed synchronously without waiting for the necessary signals, resulting in two distinct race conditions. The first occurs when the attachment of CCS buffers happens after the copy operation starts, potentially exposing partially copied metadata. The second occurs when these buffers are detached before a copy job has completed, causing potential data loss. The resolution involves reordering the attachment to ensure it precedes the submission of copy jobs and enforcing a wait for the completion of relevant signals before detaching buffers.

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