CVE-2022-48808 is a vulnerability identified in the Linux kernel specifically affecting systems using Distributed Switch Architecture (DSA) with Marvell DPAA2 Ethernet switches, such as those found in LX2160A platforms. The flaw manifests during system shutdown or reboot sequences when the DSA master network device (dpaa2-eth) is active. The root cause is a race condition and improper handling of network device deregistration events. When the DSA master device unbinds during shutdown, the kernel attempts to close network interfaces that have already been unregistered, leading to a kernel panic due to an invalid memory access. The panic occurs in the function dsa_slave_netdevice_event(), which handles NETDEV_GOING_DOWN notifications. The issue arises because after the DSA slave interfaces are unregistered by dsa_switch_shutdown(), the NETDEV_GOING_DOWN handler still attempts to close these now non-existent slave interfaces, causing a use-after-free or null pointer dereference. The vulnerability is triggered by a reboot or shutdown event and results in a denial of service (DoS) via kernel panic, which halts the system. The fix involves resetting the master->dsa_ptr pointer to NULL after slaves stop being uppers of the DSA master, preventing further notifier events on the master device and avoiding the panic. This vulnerability affects specific Linux kernel versions incorporating the affected DSA driver code and is relevant to embedded or specialized systems using Marvell DPAA2 Ethernet switches. No known exploits are reported in the wild, and no CVSS score has been assigned yet.

For European organizations, the primary impact of CVE-2022-48808 is a potential denial of service on Linux-based embedded systems or network devices using Marvell DPAA2 Ethernet switches with the DSA framework. This could disrupt critical infrastructure or industrial control systems relying on such hardware, causing unexpected reboots or system halts during shutdown or reboot operations. Enterprises deploying network appliances, telecommunications equipment, or specialized Linux-based devices in sectors such as manufacturing, energy, or telecommunications could face operational interruptions. While this vulnerability does not directly lead to remote code execution or data breach, the resulting kernel panic can cause downtime and affect availability of services. Organizations with automated reboot or shutdown procedures might experience repeated failures, impacting maintenance windows or system updates. The vulnerability is less likely to affect general-purpose Linux servers or desktops, limiting its scope primarily to embedded or specialized network hardware. However, given the critical role of network infrastructure in European digital ecosystems, even localized DoS conditions can have cascading effects on business continuity and service reliability.

To mitigate CVE-2022-48808, organizations should: 1) Identify Linux systems using the LX2160A platform or other hardware with Marvell DPAA2 Ethernet switches and verify if the kernel version includes the vulnerable DSA driver code. 2) Apply the official Linux kernel patches that reset the master->dsa_ptr pointer after slave interfaces are detached, as incorporated in kernel versions released after this vulnerability was disclosed. 3) If immediate patching is not feasible, avoid rebooting or shutting down affected systems while the DSA master device is active, or implement controlled shutdown sequences that ensure DSA interfaces are properly quiesced before reboot. 4) Monitor system logs for kernel panics or Oops messages related to dsa_slave_netdevice_event or dpaa2_eth drivers to detect potential triggering of this issue. 5) Engage with hardware vendors or Linux distribution maintainers for updated kernel releases or backported fixes tailored to embedded platforms. 6) Incorporate this vulnerability into incident response and maintenance planning to minimize operational impact during patch deployment. 7) Consider network segmentation or redundancy to isolate affected devices and maintain service availability during remediation.