Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
hwmon: (gpio-fan) Fix use-after-free in alarm work
fan_alarm_irq_handler() queues fan_data->alarm_work, but nothing cancels it. fan_alarm_notify() dereferences fan_data and its hwmon device. On unbind, devres frees the interrupt, which only waits for the handler itself, and then releases the hwmon device and fan_data, so a pending fan_alarm_notify() can run after those frees.
Replace INIT_WORK() with devm_work_autocancel(), registered before devm_request_irq(). The devres cleanup then frees the interrupt first, so no new work can be queued, and cancels the work while fan_data and the hwmon device are still alive.
This issue was found by an in-house static analysis tool.
Details
- Affected product:
- AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 7 ELS , Debian 10 ELS , Debian 11 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- linux @ 5.10.259 (+17 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| Debian 12 | Planned | — |
| Debian 13 | Will Not Fix |
17 kernels
|