CVE-2022-49487 in Linux
Summary
by MITRE • 02/26/2025
In the Linux kernel, the following vulnerability has been resolved:
mtd: rawnand: intel: fix possible null-ptr-deref in ebu_nand_probe()
It will cause null-ptr-deref when using 'res', if platform_get_resource() returns NULL, so move using 'res' after devm_ioremap_resource() that will check it to avoid null-ptr-deref.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 02/26/2025
The vulnerability identified as CVE-2022-49487 resides within the Linux kernel's MTD (Memory Technology Device) subsystem, specifically affecting the rawnand driver implementation for intel platforms. This issue manifests in the ebu_nand_probe() function where improper resource handling leads to a potential null pointer dereference condition. The vulnerability represents a classic software defect that can be exploited to cause system instability or denial of service conditions.
The technical flaw occurs due to improper ordering of operations within the device probe function where platform_get_resource() is called to retrieve platform resource information, but the subsequent check for NULL return value is deferred until after the resource pointer is used. When platform_get_resource() returns NULL indicating that no valid resource information was found, the code proceeds to use this null pointer in subsequent operations, specifically in the devm_ioremap_resource() call. This ordering issue creates a race condition where the system attempts to dereference a null pointer, leading to immediate kernel oops or system crash.
From an operational perspective, this vulnerability presents a significant risk to embedded systems and devices that rely on Intel-based NAND flash controllers through the MTD subsystem. The null pointer dereference can occur during system boot when the kernel attempts to initialize the NAND device driver, potentially causing complete system failure or requiring manual intervention to recover. The impact extends beyond simple denial of service as it can affect device reliability in production environments where kernel stability is paramount.
The vulnerability aligns with CWE-476 which specifically addresses null pointer dereference conditions in software development. It also maps to ATT&CK technique T1499.001 which covers network denial of service attacks, as this vulnerability can be leveraged to cause system instability. The root cause stems from improper resource management practices where defensive programming principles are not properly implemented in the driver initialization sequence.
Mitigation strategies should focus on applying the kernel patch that reorders the resource handling operations to ensure proper NULL checking before pointer usage. System administrators should prioritize updating affected kernel versions to include the fix that moves the resource usage after the devm_ioremap_resource() call which inherently performs the necessary NULL validation. Additionally, implementing proper kernel hardening measures and monitoring for unusual system behavior during device initialization can help detect potential exploitation attempts. Organizations should also consider implementing automated patch management systems to ensure timely deployment of security updates across all affected platforms.