CVE-2026-31485

A flaw was found in the spi-fsl-lpspi driver within the Linux kernel. This vulnerability, identified as a Use-After-Free (UAF) issue, stems from a teardown order problem during the unregistration of the Serial Peripheral Interface (SPI) controller. When a running SPI transfer attempts to access deallocated memory during the synchronous teardown of Direct Memory Access (DMA) channels, it can lead to a NULL pointer dereference. This ultimately causes the system to crash, resulting in a Denial of Service (DoS).

Upstream switched the Freescale LPSPI controller to explicit register/unregister ordering so DMA teardown cannot race devm-deferred controller release. Red Hat recommends patched kernels for systems using this SPI host. Where the controller is optional, unloading spi_fsl_lpspi reduces exposure until updates deploy.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

To mitigate this issue, prevent the spi_fsl_lpspi module from being loaded. See https://access.redhat.com/solutions/41278 for instructions.