The Linux kernel iwlwifi driver mishandles firmware restarts by not stopping transmission queues during the restart process. When the firmware crashes (e.g., on Intel BE201 Wi-Fi 7 hardware), the driver sets a flag indicating hardware restart, but the transmit function continues dequeuing frames and attempting to send them. Since the firmware is non-responsive, transmissions fail immediately, causing a loop of dequeue-send-fail-free operations that waste CPU cycles and cause slab memory fragmentation. The fix adds a guard in the transmit function to stop all transmissions during firmware restart, aligning with existing protections in the receive path and allocation workers. This prevents resource exhaustion and stabilizes operation during firmware recovery.

Under high-throughput network conditions, such as active UDP or SSH traffic, the vulnerability causes excessive CPU usage and memory pressure due to continuous failed transmission attempts and rapid memory allocation/free cycles. This can degrade system performance and stability on affected Intel Wi-Fi 7 devices running vulnerable Linux kernel versions. There is no indication of direct security compromise or remote code execution from this issue.

A fix has been implemented in the Linux kernel to add a guard that stops transmission during firmware restart in the iwlwifi driver. Users should update to a Linux kernel version that includes this fix (e.g., kernel 6.19.5 or later where tested). Since this is a kernel-level fix, applying the official kernel update from the distribution or vendor is the recommended remediation. Patch status is not explicitly confirmed in the advisory; users should verify with their Linux distribution's security updates for the official fix.