CVE-2026-72095 dma-fence: Make dma_fence_dedup_array() robust against 0-count input
A logic error in the Linux kernel's dma-fence deduplication function could lead to a null pointer dereference and system crash when processing zero-count inputs.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-72095?
CVE-2026-72095 is a high-severity vulnerability in Linux, published on 15 Aug 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:
dma-fence: Make dma_fence_dedup_array() robust against 0-count input
dma_fence_dedup_array() returns 1 when called with num_fences == 0: the for-loop body never executes, j stays at 0, and the final `return ++j` yields 1. This contradicts both the kernel-doc ("Return: Number of unique fences remaining in the array") and the natural expectation that 0 input gives 0 output.
The caller __dma_fence_unwrap_merge() bails out via the `if (count == 0 || count == 1)` fast path and so is save.
But amdgpu_userq_wait_*() could reach the dedup call with a zero local count and dereference an uninitialized fence slot in the array.
Make the contract match the documentation by returning 0 early. This also skips an unnecessary sort() call on an empty array.
Weakness: CWE-170
Which versions are affected by CVE-2026-72095?
How do I fix CVE-2026-72095?
Apply the vendor's patch.
Is CVE-2026-72095 being exploited?
There is no known exploitation of CVE-2026-72095 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-72095, DEBIAN-CVE-2026-72095, GHSA-cgwr-m873-g7w9, UBUNTU-CVE-2026-72095.