CVE-2026-31442: dmaengine: idxd: Fix possible invalid memory access after FLR
In the Linux kernel, the following vulnerability has been resolved:
dmaengine: idxd: Fix possible invalid memory access after FLR
In the case that the first Function Level Reset (FLR) concludes correctly, but in the second FLR the scratch area for the saved configuration cannot be allocated, it's possible for a invalid memory access to happen.
Always set the deallocated scratch area to NULL after FLR completes.
Affected Software
Event History
Frequently Asked Questions
What conditions are required to trigger the invalid memory access?
The issue requires a first Function Level Reset (FLR) to complete successfully, followed by a second FLR in which allocation of the scratch area used for saved configuration fails. The stale deallocated scratch-area pointer can then be accessed.
Which systems are exposed?
Systems running the Linux kernel with the dmaengine idxd component are relevant. The provided information does not identify affected kernel versions, hardware models, or whether idxd is enabled by default.
What is the immediate mitigation if an update cannot be applied?
The provided fix ensures that the scratch-area pointer is set to NULL after FLR completes. No configuration-based workaround or operational mitigation is specified in the available information.