CVE-2026-89800

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.