CVE-2025-38703: drm/xe: Make dma-fences compliant with the safe access rules

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-09-04 · updated 2026-10-19
Weakness: CWE-416

Description

In the Linux kernel, the following vulnerability has been resolved: drm/xe: Make dma-fences compliant with the safe access rules Xe can free some of the data pointed to by the dma-fences it exports. Most notably the timeline name can get freed if userspace closes the associated submit queue. At the same time the fence could have been exported to a third party (for example a sync_fence fd) which will then cause an use- after-free on subsequent access. To make this safe we need to make the driver compliant with the newly documented dma-fence rules. Driver has to ensure a RCU grace period between signalling a fence and freeing any data pointed to by said fence. For the timeline name we simply make the queue be freed via kfree_rcu and for the shared lock associated with multiple queues we add a RCU grace period before freeing the per GT structure holding the lock.

Affected products

Linux kernel: from 6.8 before 6.12.43; from 6.13 before 6.15.11; from 6.16 before 6.16.2 — fixed in 6.12.43, 6.15.11, 6.16.2

How to fix

Upgrade to a fixed version: Linux kernel 6.12.43, 6.15.11, 6.16.2. Check the vendor advisory for mitigations.

References

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