UBUNTU-CVE-2026-98161: Medium severity ubuntu/linux-hwe-edge vulnerability
In the Linux kernel, the following vulnerability has been resolved: nvdimm: pmem: keep PREFLUSH before data writes pmemsubmitbio() records a REQPREFLUSH error, but continues to copy the bio data and can later overwrite the error with a successful REQFUA flush. That lets data writes run after a failed preflush and can complete the bio successfully despite the failed ordering barrier. Run the REQPREFLUSH flush synchronously before touching the bio data and complete the bio with the flush error if it fails. Keep asynchronous flush chaining for REQFUA. At that point, data copy has completed and the parent bio can wait for the chained flush bio.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Compensating control
In pmem_submit_bio(), run the REQ_PREFLUSH flush synchronously before copying or otherwise touching bio data, complete the bio with the flush error if it fails, and retain asynchronous flush chaining for REQ_FUA.