UBUNTU-CVE-2026-64065

In the Linux kernel, the following vulnerability has been resolved: netfs: fix VMBUGONFOLIO issue in netfswritebegin call The multiple runs of generic/013 test-case is capable to reproduce a kernel BUG at mm/filemap.c:1504 with probability of 30%. while true; do sudo ./check generic/013 done...

CVE-2026-64065

CVE-2026-64065 affects the Linux kernel's netfs subsystem , specifically a VM_BUG_ON_FOLIO() assertion failure in netfs_write_begin() . The root cause is that folio_unlock() is called on an already-unlocked folio (at mm/filemap.c:1504), triggered through the Ceph filesystem write path (ceph_write...