cbcvebase.
CVE-2025-40249
published 2025-12-04

CVE-2025-40249: 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…

PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.14%
3.9th percentile
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 device went down to zero but BEFORE the .release() callback was called from the workqueue and so BEFORE we unregistered from the notifier. Using the regular get_file() routine in this situation triggers the following warning: struct file::f_count incremented from zero; use-after-free condition present! So use the get_file_active() variant that will return NULL on file descriptors that have been or are being released.

Affected

7 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.17.10-1 (forky)linux 6.17.10-1 (forky)
linuxlinux
linuxlinux>= 40b7c49950bd56c984b1f6722f865b922879260e < dccc6daa8afa0f64c432e4c867f275747e3415e1dccc6daa8afa0f64c432e4c867f275747e3415e1
linuxlinux>= 40b7c49950bd56c984b1f6722f865b922879260e < d4cd0902c156b2ca60fdda8cd8b5bcb4b0e9ed64d4cd0902c156b2ca60fdda8cd8b5bcb4b0e9ed64
linuxlinux_kernel>= 0 < 6.17.10-16.17.10-1
linuxlinux_kernel>= 0 < 6.17.0-19.196.17.0-19.19
linuxlinux_kernel>= 6.13.0 < 6.17.106.17.10

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.2HIGH
vendor_ubuntu7.2HIGH
vendor_redhat7.1MEDIUM
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