CVE-2026-31648

A flaw was found in the Linux kernel. A race condition in the filemap_map_pages() function can lead to an integer overflow during the calculation of nr_pages. This overflow causes the system to map memory beyond the intended boundaries of a memory block, potentially corrupting critical page metadata. An attacker with local access could exploit this to cause system instability or a denial of service.

A vm_fault_t vs page-count type mix-up could overflow nr_pages in filemap_map_pages() under races, skipping needed prefault work or mis-sizing loops. Red Hat treats this as core MM correctness with local trigger.

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.