The Linux kernel network driver for the mana interface uses a receive completion queue sized exactly one entry per posted receive work queue entry. The driver appends an additional fence completion entry after packet completions, but the queue size calculation does not reserve an extra slot for this fence. When the queue becomes full of packet completions, no slot is guaranteed for the fence completion, causing it to be dropped while the driver holds the runtime lock during its timeout period. This flaw can stall packet processing and lead to a service interruption, qualifying as a denial‑of‑service condition.

All Linux kernel builds that contain the mana networking driver before the patch referenced in the advisory (commit 1e43c4 and its follow‑up commits). The issue affects any deployment that compiles the mana driver without the corrected queue‑size logic, regardless of distribution.

The CVSS score is 5.5, the EPSS score is <1%, and the vulnerability is not listed in the CISA KEV catalog. Attackers would need to generate traffic that fully populates the receive completion queue to trigger the flaw, which suggests a local or network‑based denial of service rather than remote code execution. The low probability of exploitation combined with the potential to stall packet processing makes the risk moderate, but the impact of interrupting network traffic warrants prompt mitigation.