Kernel panic in the it82xx2 USB device controller driver via re-initialization of a busy delayable work item
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 4.4.2
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: partial
Summary
The ITE it82xx2 USB device-controller driver initialized its bus-suspend detection work with k_work_init_delayable(&priv->suspended_work, suspended_handler) inside it82xx2_enable() (the driver's .enable op) in drivers/usb/udc/udc_it82xx2.c. This work item is scheduled essentially continuously while the USB bus is active: the interrupt handler reschedules it on every SOF frame and suspended_handler() reschedules itself, so its timeout node is normally linked in the kernel timeout list / a workqueue pending queue. k_work_init_delayable() (kernel/work.c) unconditionally overwrites the entire k_work_delayable structure, including its timeout and queue linkage, with no busy check. Because it82xx2_disable() does not cancel the work, a normal disable-then-enable cycle re-runs api->enable() (udc_enable() only rejects a redundant enable, not a re-enable after disable) and re-initializes the still-pending work in place, corrupting the kernel timeout/workqueue linked lists and causing a kernel panic. An external USB host — for example a host performing USB DFU detach (dfu-util --detach) or forcing repeated attach/reset/re-enumeration — drives the udc_disable()/udc_enable() transitions and controls suspend/resume timing, so it can arrange for the suspend work to be pending across a re-enable. This yields an unauthenticated denial of service (kernel panic) reachable across the USB boundary from a removable, physically-connected host, with no confidentiality or integrity impact demonstrated. The fix moves the k_work_init_delayable() call into the one-time preinit function so the work is initialized exactly once, eliminating the re-initialization of an in-use item.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- zephyr
From 3.7.0 · fixed in 4.4.2