CVE-2026-68272 drm/amdgpu: validate CP_GFX_SHADOW chunk size in CS pass1
An unprivileged local user can cause a kernel crash by submitting a zero-length CP_GFX_SHADOW chunk to the AMDGPU driver.
- 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-2026-68272?
CVE-2026-68272 is a vulnerability in Linux, published on 10 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:
drm/amdgpu: validate CP_GFX_SHADOW chunk size in CS pass1
Add a minimum-length check for the AMDGPU_CHUNK_ID_CP_GFX_SHADOW chunk in amdgpu_cs_pass1(), matching the gate already present for the IB, FENCE and BO_HANDLES chunk types.
The CP_GFX_SHADOW case previously shared a bare break with the dependency and syncobj chunk types, which do not dereference a fixed-size struct. When userspace submits this chunk with length_dw == 0, vmemdup_array_user() is called with size 0 and returns ZERO_SIZE_PTR, which passes the IS_ERR() check. amdgpu_cs_p2_shadow() then dereferences chunk->kdata as a struct drm_amdgpu_cs_chunk_cp_gfx_shadow (reading shadow->flags), faulting on the ZERO_SIZE_PTR and causing a NULL-pointer dereference.
This is reachable by an unprivileged process in the render group. Reject undersized chunks with -EINVAL during pass1 so the bad submission is rejected before pass2 ever dereferences the data.
(cherry picked from commit 7f61b2eef7415eccdb40850aca0de94211948657)
Which versions are affected by CVE-2026-68272?
How do I fix CVE-2026-68272?
Apply the vendor's patch.
Is CVE-2026-68272 being exploited?
There is no known exploitation of CVE-2026-68272 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-68272, DEBIAN-CVE-2026-68272, GHSA-c7h3-6rq5-x6h3, UBUNTU-CVE-2026-68272.