fuse_open() in the Linux kernel incorrectly handles the scenario where a DAX‑truncated file operation fails due to a signal interrupt. The function acquires a filemap invalidate lock but, when fuse_dax_break_layouts() fails, the code path that releases the lock is skipped. The leaked read/write semaphore can then cause any subsequent operations, such as a fault or truncate on the file, to block indefinitely because the resource remains locked. This results in a denial of service for processes that attempt those operations.

All Linux kernel distributions that include the FUSE component are affected. No specific kernel version is listed in the advisory, so the issue applies to the kernel source regardless of release.

The vulnerability does not appear in the CISA KEV catalog and no EPSS score is available, so the likelihood of widespread exploitation is uncertain. The flaw requires an attempt to open a FUSE‑mounted file with the O_TRUNC flag (or a similar truncate operation) while the DAX pages are busy, and it culminates in the kernel leaving a lock unreleased. An attacker with local access could trigger the failure by sending a signal during the wait, causing the lock to leak and potentially halting all subsequent open or truncate operations on that file. This can lead to service disruption for user processes and any services that rely on that file, with the impact extending across the system until the offending process exits or the machine is rebooted.