CVE-2025-38492

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

netfs: Fix race between cache write completion and ALL_QUEUED being set

When netfslib is issuing subrequests, the subrequests start processing

immediately and may complete before we reach the end of the issuing

function. At the end of the issuing function we set NETFS_RREQ_ALL_QUEUED

to indicate to the collector that we aren't going to issue any more subreqs

and that it can do the final notifications and cleanup.

Now, this isn't a problem if the request is synchronous

(NETFS_RREQ_OFFLOAD_COLLECTION is unset) as the result collection will be

done in-thread and we're guaranteed an opportunity to run the collector.

However, if the request is asynchronous, collection is primarily triggered

by the termination of subrequests queuing it on a workqueue. Now, a race

can occur here if the app thread sets ALL_QUEUED after the last subrequest

terminates.

This can happen most easily with the copy2cache code (as used by Ceph)

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References