CVE-2026-74418

Summary

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

dma-fence: Fix potential tracepoint null pointer dereferences

Trace_dma_fence_signaled, trace_dma_fence_wait_end and trace_dma_fence_destroy can all currently dereference a null fence->ops pointer after it has been reset on fence signalling.

Lets use the safe string getters for most tracepoints to avoid this class of a problem, while for the signal tracepoint we move it to before ops are cleared to avoid losing the driver and timeline name information. Apart from moving it we also need to add a new tracepoint class to bypass the safe name getters since the signaled bit is already set.

For dma_fence_init we also need to use the new tracepoint class since the rcu read lock is not held there, and we can do the same for the enable signaling since there we are certain the fence cannot be signaled while we are holding the lock and have even validated the fence->ops.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux541c8f2468b933acc5d129e84bd264923675a66e < 4e01fc9a5bc49b04fad403ffa71299b35e132ca8affected
LinuxLinux541c8f2468b933acc5d129e84bd264923675a66e < e94b9f01543cc6a83538c2c2cc645a424d3015caaffected
LinuxLinux7.1affected
LinuxLinux0 < 7.1unaffected
LinuxLinux7.1.5 <= 7.1.*unaffected
LinuxLinux7.2-rc1 <= *unaffected

Weaknesses

References