CVE-2024-46866

In the Linux kernel, the following vulnerability has been resolved:

drm/xe/client: add missing bo locking in show_meminfo()

bo_meminfo() wants to inspect bo state like tt and the ttm resource, however this state can change at any point leading to stuff like NPD and UAF, if the bo lock is not held. Grab the bo lock when calling bo_meminfo(), ensuring we drop any spinlocks first. In the case of object_idr we now also need to hold a ref.

v2 (MattB)

• Also add xe_bo_assert_held()

(cherry picked from commit 4f63d712fa104c3ebefcb289d1e733e86d8698c7)

Weakness

The product does not properly acquire or release a lock on a resource, leading to unexpected resource state changes and behaviors.

Affected Software

Extended Description

Locking is a type of synchronization behavior that ensures that multiple independently-operating processes or threads do not interfere with each other when accessing the same resource. All processes/threads are expected to follow the same steps for locking. If these steps are not followed precisely - or if no locking is done at all - then another process/thread could modify the shared resource in a way that is not visible or predictable to the original process. This can lead to data or memory corruption, denial of service, etc.

Potential Mitigations

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/25.html
• https://cwe.mitre.org/data/definitions/26.html
• https://cwe.mitre.org/data/definitions/27.html

References

• https://git.kernel.org/stable/c/94c4aa266111262c96c98f822d1bccc494786fee
• https://git.kernel.org/stable/c/abc8feacacf8fae10eecf6fea7865e8c1fee419c