CVE-2026-68152amt: fix use-after-free in AMT delayed works

Official description

In the Linux kernel, the following vulnerability has been resolved: amt: fix use-after-free in AMT delayed works When an AMT device is removed, pending delayed works can still access the freed amt_dev structure, which may result in kernel crashes or memory corruption. amt_dev_stop() cancels req_wq and discovery_wq with cancel_delayed_work_sync(), but these works can be scheduled again from event_wq after the cancellation. This allows delayed works to access the freed amt_dev structure after the netdev has been released. The following is a simple race scenario: CPU0 CPU1 amt_dev_stop() cancel_delayed_work_sync() amt_event_work() mod_delayed_work(req_wq) free netdev req_wq accesses freed amt_dev Use disable_delayed_work_sync() in amt_dev_stop() to prevent req_wq and discovery_wq from being queued again and wait for running work items to complete. The delayed works are disabled after initialization in amt_newlink() and enabled only when the device is successfully opened. This keeps the delayed work lifecycle synchronized with the lifetime of the AMT device.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/a46bfa01e01df0f6f6dc4b0be18db002d6d2dbd2
• https://git.kernel.org/stable/c/1a644db2cf59f164cdf3c75995bab5aadc097528
• https://git.kernel.org/stable/c/006340cf06881b6ff49767d8b6f3c4f7b892670c
• https://git.kernel.org/stable/c/ea20c44935d6142daecfa9b39d635033a7553e1b