CVE-2026-89800

/// Technical description

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

drm/nouveau/uvmm: clear the dirty flag when unwinding an OP_UNMAP_SPARSE

A successful OP_UNMAP_SPARSE marks its region dirty with

nouveau_uvma_region_dirty() and defers the teardown to

nouveau_uvmm_bind_job_cleanup(); it does not remove the region from

uvmm->region_mt.

If a later op in the job fails, the unwind path never clears reg->dirty

(set in one place, cleared nowhere) and sets op->reg = NULL, so cleanup

skips the teardown. The region is left in the tree with dirty set and its

completion never signalled. Later binds over that range then fail

permanently -- -ENOENT or -EINVAL from the dirty checks, or an unkillable

wait_for_completion() in bind_validate_region() -- for the lifetime of

the uvmm.

Clear reg->dirty when the unwind reverts the sparse unmap, restoring the

region to the state it was found in.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References