CVE-2026-64149

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A flaw exists in the dma map resource() function where a sanity check using pfn valid() incorrectly identifies certain Memory-Mapped I/O (MMIO) addresses as RAM. On ARM64 systems using SPARSEMEM, MMIO addresses sharing a section with RAM can trigger a false positive, causing the function to return DMA MAPPING ERROR. This occurs because pfn valid() only verifies the availability of the memory map for a Page Frame Number (PFN) without ensuring the PFN is actually backed by RAM. An example of this behavior is observed on the Raspberry Pi 4 during the spi bcm2835 probe, where the SPI FIFO register falls within the same sparsemem section as the end of the RAM.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.