CVE-2026-98828: wifi: ath9k: reject short WMI command responses

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

wifi: ath9k: reject short WMI command responses

ath9kwmirspcallback() removes the validated WMI header and copies the number of bytes expected by the waiting command into its response buffer. A device response shorter than that expectation can therefore be read beyond the skb payload.

Record -EMSGSIZE for a short response, complete the waiter, and return the stored status from the command path. This also prevents callers from consuming stale response bytes as a successful reply.