CVE-2024-50297 is a vulnerability identified in the Linux kernel specifically affecting the Xilinx AXI Ethernet (axienet) driver within the network subsystem. The flaw arises from a race condition related to the handling of transmit (Tx) packets in the dynamic queue limits (dql) mechanism when used in conjunction with the DMA engine. The vulnerability occurs because Tx packets are enqueued into the dql after the DMA engine has started, which can cause the DMA engine's Tx transfer to begin and potentially execute the dql dequeue completion callback before the packet is actually queued. This improper sequencing leads to a kernel crash, as evidenced by a BUG triggered in the kernel's dynamic_queue_limits.c code during stress testing with iperf. The root cause is that the DMA engine's Tx callback (axienet_dma_tx_cb) and subsequent tasklet handling can complete dequeuing operations prematurely, causing inconsistent queue state and kernel oops. The fix involves ensuring that packets are enqueued into the dql before the DMA engine is started, thus preventing the race condition and subsequent kernel crash. This vulnerability affects Linux kernel versions containing the specified commit (6a91b846af85a24241decd686269e8e038eb13d1) and is relevant to systems using the Xilinx axienet driver, commonly found in embedded and specialized networking hardware. No known exploits are reported in the wild, and no CVSS score has been assigned yet.

For European organizations, the impact of CVE-2024-50297 primarily concerns systems running Linux kernels with the affected axienet driver, which is typically used in embedded devices or specialized network equipment leveraging Xilinx FPGA-based Ethernet interfaces. The vulnerability can cause kernel crashes leading to denial of service (DoS) conditions, potentially disrupting network communications and critical services relying on these devices. While this does not directly lead to privilege escalation or data leakage, the resulting instability can affect availability and reliability of network infrastructure. Organizations in sectors such as telecommunications, industrial automation, and research institutions using Xilinx-based networking hardware are at higher risk. The disruption could impact operational technology (OT) environments and network edge devices, which are critical for maintaining continuous service. Given the absence of known exploits, the immediate threat level is moderate, but the potential for service outages necessitates prompt attention.

To mitigate this vulnerability, European organizations should: 1) Identify and inventory all Linux systems running kernels with the affected axienet driver, focusing on embedded and network devices using Xilinx Ethernet interfaces. 2) Apply the official Linux kernel patches that reorder the enqueue operation to occur before the DMA engine starts, as committed in the relevant kernel update (commit 6a91b846af85a24241decd686269e8e038eb13d1). 3) For devices where kernel patching is not immediately feasible, consider implementing network segmentation and redundancy to minimize impact from potential device crashes. 4) Monitor kernel logs and system stability metrics for signs of the described kernel BUG or unexpected reboots, especially under network stress conditions like iperf testing. 5) Engage with hardware vendors to obtain firmware or driver updates that incorporate the fix if the affected devices are vendor-supplied. 6) Incorporate this vulnerability into vulnerability management and patching cycles, prioritizing devices critical to network availability. 7) Test patches in controlled environments to ensure no regressions in device functionality before wide deployment.