CVE-2024-26807 is a vulnerability in the Linux kernel specifically affecting the cadence-quadspi driver, which is responsible for managing Quad SPI (Serial Peripheral Interface) flash memory devices. The root cause is a programming error in the runtime power management suspend and resume functions (runtime_suspend() and runtime_resume()). Both functions incorrectly retrieve device driver data using dev_get_drvdata(dev) but assign it to two different pointer types: struct cqspi_st* and struct spi_controller*. The cadence-quadspi driver's probe function sets the device driver data pointer to the address of a struct cqspi_st instance, which is private data allocated alongside the spi_controller structure. However, the runtime_resume() function erroneously treats this pointer as a struct spi_controller*, leading to an invalid memory reference. This type confusion causes memory corruption and kernel crashes during device initialization and power management operations. The issue manifests during the probe phase when the device is enabled with runtime power management, triggering the runtime_resume() callback with the wrong pointer. The exact impact depends on memory contents but can cause immediate kernel panics or unpredictable behavior. This vulnerability affects all platforms using the cadence-quadspi driver in the Linux kernel, which is commonly found in embedded systems and devices relying on Quad SPI flash memory for firmware or storage. No CVSS score has been assigned yet, and no known exploits are reported in the wild at this time.

For European organizations, the impact of CVE-2024-26807 depends largely on their use of embedded Linux systems or devices that incorporate the cadence-quadspi driver. This includes industrial control systems, IoT devices, networking equipment, and specialized hardware that rely on Quad SPI flash memory. A successful exploitation can lead to kernel crashes and system instability, resulting in denial of service conditions. In critical infrastructure sectors such as manufacturing, energy, transportation, or healthcare, such disruptions could halt operations or degrade service availability. Additionally, memory corruption could potentially be leveraged for privilege escalation or arbitrary code execution by sophisticated attackers, although no such exploits are currently known. The vulnerability undermines system reliability and could increase maintenance costs due to unexpected reboots or failures. Organizations relying on Linux-based embedded devices should assess their exposure, especially if these devices are part of critical operational technology environments.

To mitigate CVE-2024-26807, organizations should: 1) Apply the official Linux kernel patches that correct the pointer usage in the cadence-quadspi driver's runtime_suspend() and runtime_resume() functions as soon as they become available. 2) Identify all devices and systems running affected Linux kernel versions with the cadence-quadspi driver enabled, including embedded and IoT devices, and prioritize patching or firmware updates. 3) Where patching is not immediately feasible, consider disabling runtime power management for the cadence-quadspi device as a temporary workaround to prevent triggering the faulty resume logic. 4) Implement robust monitoring for kernel crashes and system reboots that could indicate exploitation attempts or instability related to this vulnerability. 5) Engage with device vendors to obtain updated firmware or kernel versions that incorporate the fix. 6) For critical systems, conduct thorough testing of updated kernels in staging environments to ensure stability and compatibility before deployment. 7) Maintain strict access controls and network segmentation to limit exposure of vulnerable devices to untrusted networks or users, reducing the risk of exploitation.