In the Linux kernel, the following vulnerability has been resolved: mtd: spinand: fix NULL pointer dereference with no ECC engine When… (CVE-2026-98931)

The Linux kernel SPI-NAND driver had a vulnerability where setting "nand-no-ecc-engine" in the device tree caused nanddev_get_ecc_engine() to return success but leave nand->ecc.engine as NULL. The SPI-NAND code then dereferenced this NULL pointer to test for a pipelined ECC engine, causing an immediate kernel oops on device probing. The fix adds a nand_ecc_is_pipelined() helper that includes a NULL check, preventing the dereference of a NULL pointer and ensuring safer ECC engine handling.

This vulnerability leads to a NULL pointer dereference causing a kernel oops (crash) during SPI-NAND device probing when no ECC engine is configured. This results in denial of service on affected systems running the vulnerable Linux kernel versions.

A fix has been implemented in the Linux kernel to address this issue by adding a helper function that safely checks the ECC engine pointer before dereferencing. Users should update to the fixed kernel version containing this patch. No other mitigation is indicated.