Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
drm/vc4: Shut down BO cache timer before teardown
The BO cache timer callback schedules time_work, and time_work can rearm the timer through vc4_bo_cache_free_old().
vc4_bo_cache_destroy() deletes the timer and then cancels the work, which does not break that cycle: the work being cancelled can rearm the timer, and the timer then queues work again after teardown.
Use timer_shutdown_sync() instead, so the timer cannot be rearmed and the cycle ends with cancel_work_sync().
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Debian 10 ELS , TuxCare 9.6 ESU
- Affected packages:
- kernel @ 4.18.0 (+5 more)