CVE-2024-44956: drm/xe/preempt_fence: enlarge the fence critical section
In the Linux kernel, the following vulnerability has been resolved:
drm/xe/preemptfence: enlarge the fence critical section
It is really easy to introduce subtle deadlocks in preemptfenceworkfunc() since we operate on single global ordered-wq for signalling our preempt fences behind the scenes, so even though we signal a particular fence, everything in the callback should be in the fence critical section, since blocking in the callback will prevent other published fences from signalling. If we enlarge the fence critical section to cover the entire callback, then lockdep should be able to understand this better, and complain if we grab a sensitive lock like vm->lock, which is also held when waiting on preempt fences.
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2024-44956?
CVE-2024-44956 is rated as a medium severity vulnerability in the Linux kernel.
How do I fix CVE-2024-44956?
To fix CVE-2024-44956, update your Linux kernel to a fixed version such as 5.10.223-1, 6.1.123-1, or later.
Which versions of the Linux kernel are affected by CVE-2024-44956?
CVE-2024-44956 affects Linux kernel versions prior to 6.10.5.
What impact does CVE-2024-44956 have on system security?
CVE-2024-44956 can potentially lead to subtle deadlocks in the kernel, which may affect system stability.
Is CVE-2024-44956 specific to any Linux distribution?
CVE-2024-44956 is found in the Linux kernel and may affect multiple distributions that use vulnerable kernel versions.