CVE-2026-93040 dmaengine: dw-edma: Serialize channel state checks
A race condition in the Linux kernel dw-edma driver can wedge DMA channels, causing a denial of service for local attackers.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-93040?
CVE-2026-93040 is a vulnerability in Linux, published on 17 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
dmaengine: dw-edma: Serialize channel state checks
pause() and resume() read and update channel state without holding vc.lock, while the interrupt handlers update the same state under it. Take the same lock around those state checks so that request, status, and configured stay consistent.
For example, pause() can observe EDMA_ST_BUSY right before the interrupt handler completes the final descriptor and moves the channel to EDMA_ST_IDLE, and then record EDMA_REQ_PAUSE on an already idle channel. No further interrupt will acknowledge the request, and since issue_pending() requires EDMA_REQ_NONE, the channel is wedged for good: terminate_all() leaves the stale request behind, so even reconfiguring the channel does not recover it.
issue_pending() already runs under vc.lock, but it tests configured before taking it. Move that test under the lock as well, so configured, request, and status are evaluated as one channel-state snapshot.
Which versions are affected by CVE-2026-93040?
How do I fix CVE-2026-93040?
Apply the vendor's patch.
Is CVE-2026-93040 being exploited?
There is no known exploitation of CVE-2026-93040 in the wild and no public exploit code.
Sources
Also known as AZL-102329, BELL-CVE-2026-93040, DEBIAN-CVE-2026-93040, GHSA-3g95-h923-8hfc, UBUNTU-CVE-2026-93040.