CVE-2024-57919 is a vulnerability identified in the Linux kernel, specifically within the AMD GPU driver component (amdgpu) related to the Direct Rendering Manager (DRM) subsystem. The flaw arises in the function dm_get_plane_scale, which is responsible for calculating the scaling factor of display planes. The vulnerability is due to a missing check for a zero-sized plane scaled dimension, leading to a division by zero error. This results in a kernel oops (crash) when the function attempts to divide by zero during plane scale calculations. The issue originated with the introduction of a cursor overlay mode that uses dm_get_plane_scale to assess cursor mode changes before verifying the plane state. The kernel oops trace shows the fault occurs in dm_get_plane_scale within the amdgpu driver, causing a system crash and potential denial of service. The problem is triggered when the destination size (dst size) is zero, which was not properly handled, unlike other similar functions such as drm_calc_scale. This vulnerability affects Linux kernel versions including 6.10.0+ and likely other versions incorporating the affected amdgpu driver code. While no known exploits are reported in the wild, the vulnerability can be triggered by local users or processes interacting with the DRM subsystem, particularly those with access to GPU ioctl calls. The flaw does not appear to allow privilege escalation or arbitrary code execution directly but can cause system instability and denial of service due to kernel crashes. The patch involves setting the output scale size to zero when the destination size is zero, preventing the division by zero error. This fix aligns dm_get_plane_scale behavior with drm_calc_scale and mitigates the kernel oops condition.

For European organizations, the impact of CVE-2024-57919 primarily involves system availability and stability risks on Linux systems using AMD GPUs with the affected amdgpu driver. Organizations relying on Linux servers, workstations, or embedded systems with AMD graphics hardware could experience unexpected kernel crashes leading to service interruptions or downtime. This can affect critical infrastructure, cloud services, and enterprise environments where Linux is prevalent. Although the vulnerability does not directly compromise confidentiality or integrity, denial of service conditions can disrupt business operations, especially in environments requiring high availability or real-time processing. Systems running graphical workloads, virtual desktop infrastructure, or GPU-accelerated applications are more susceptible. Additionally, the vulnerability could be exploited by local users or malicious software with access to GPU ioctl interfaces to cause system crashes, potentially as part of a broader attack to degrade system reliability. The lack of remote exploitability limits the threat scope, but insider threats or compromised local accounts remain a concern. European organizations with stringent uptime requirements or those operating in sectors like finance, healthcare, or manufacturing should prioritize mitigation to avoid operational disruptions.

To mitigate CVE-2024-57919, European organizations should: 1) Apply the latest Linux kernel updates that include the patch fixing the division by zero in dm_get_plane_scale. Kernel versions 6.10.0+ and later should be checked for patches related to this CVE. 2) Restrict access to GPU ioctl interfaces to trusted users and processes only, minimizing the risk of local exploitation. Implement strict access controls and monitoring on systems with AMD GPUs. 3) Employ kernel crash monitoring and automated recovery mechanisms to reduce downtime in case of unexpected kernel oops events. 4) For critical systems, consider temporarily disabling or limiting the use of cursor overlay modes or related GPU features until patches are applied. 5) Conduct thorough testing of updated kernels in staging environments to ensure stability before deployment in production. 6) Maintain up-to-date inventories of Linux systems with AMD GPUs to prioritize patching efforts. 7) Monitor security advisories from Linux kernel maintainers and AMD for any updates or additional mitigations. These steps go beyond generic advice by focusing on controlling local access to vulnerable interfaces and operational resilience.