CVE-2026-23380

A flaw was found in the Linux kernel. A local user could exploit an issue in the tracing buffer's memory management when a process forks. If an application uses madvise(MADVISE_DOFORK), it can cause the tracing_buffers_mmap_close() function to be called multiple times, leading to a system warning and potentially a denial of service.

This flaw affects tracing buffer mmap usage with fork(). When MADVISE_DOFORK overrides VM_DONTCOPY, the user_mapped refcount isn't incremented for child VMAs, causing double-close on both processes exiting. This triggers a WARN_ON but doesn't cause memory corruption. Requires specific madvise() usage with tracing mmap.

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.