CVE-2025-40249 — Use of Expired File Descriptor in Linux

In the Linux kernel, the following vulnerability has been resolved: gpio: cdev: make sure the cdev fd is still active before emitting events With the final call to fput() on a file descriptor, the release action may be deferred and scheduled on a work queue. The reference count of that descriptor is still zero and it must not be used. It's possible that a GPIO change, we want to notify the user-space about, happens AFTER the reference count on the file descriptor associated with the character …