CVE-2024-46716 is a vulnerability identified in the Linux kernel's dmaengine subsystem, specifically within the altera-msgdma driver, which handles DMA (Direct Memory Access) operations for Altera devices. The issue arises from improper management of descriptor freeing in the msgdma_free_descriptor function. The vulnerability is due to incorrect list manipulation: the removal of list_del calls from the msgdma_chan_desc_cleanup function shifted the responsibility of removing nodes from the linked list to msgdma_free_descriptor. However, the implementation failed to correctly remove the first nodes from the descriptor list, leading to descriptors not being properly freed. This improper freeing of descriptors can cause resource leaks, potentially leading to memory corruption or exhaustion of kernel resources. The fix involved replacing list_add_tail with list_move_tail in msgdma_free_descriptor to ensure proper list node management and descriptor cleanup. The vulnerability affects specific Linux kernel versions identified by the commit hash 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2. Although no known exploits are currently reported in the wild, the flaw could be leveraged by attackers with local access to cause denial of service or potentially escalate privileges by corrupting kernel memory structures. Since this vulnerability is in a kernel driver related to DMA operations, it is particularly relevant for systems running Linux kernels with Altera FPGA or SoC hardware using the altera-msgdma driver. The vulnerability does not require user interaction but likely requires local access or code execution privileges to exploit. No CVSS score has been assigned yet.

For European organizations, the impact of CVE-2024-46716 depends largely on their deployment of Linux systems utilizing Altera hardware with the affected altera-msgdma driver. Organizations in sectors such as telecommunications, industrial control systems, and embedded device manufacturers—where Altera FPGA-based hardware is common—may be at higher risk. Exploitation could lead to denial of service conditions by exhausting kernel resources or causing kernel crashes, impacting system availability. In critical infrastructure or manufacturing environments, such disruptions could have significant operational consequences. Additionally, if exploited for memory corruption, there is a risk of privilege escalation, potentially allowing attackers to gain elevated access to systems. Given the widespread use of Linux in European data centers, cloud environments, and embedded devices, organizations relying on affected kernel versions should be vigilant. However, the lack of known exploits and the requirement for local access reduce the immediate threat level for most enterprises. Nevertheless, the vulnerability poses a moderate risk to organizations with relevant hardware and kernel versions, especially those with stringent uptime and security requirements.

To mitigate CVE-2024-46716, European organizations should: 1) Identify Linux systems running kernels that include the affected altera-msgdma driver version (commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2) and verify if they utilize Altera FPGA or SoC hardware. 2) Apply the official Linux kernel patches that address the descriptor freeing logic in the dmaengine altera-msgdma driver as soon as they become available from trusted sources such as the Linux kernel mailing list or vendor security advisories. 3) For systems where patching is not immediately feasible, consider disabling or unloading the altera-msgdma driver if the hardware is not in use or if alternative drivers are available. 4) Implement strict access controls to limit local user access to trusted personnel only, reducing the risk of exploitation by unprivileged users. 5) Monitor system logs and kernel messages for unusual behavior or crashes related to DMA operations. 6) Engage with hardware and Linux distribution vendors to ensure timely updates and support. 7) Incorporate this vulnerability into vulnerability management and incident response plans to ensure rapid detection and remediation.