CVE-2026-89800drm/nouveau/uvmm: clear the dirty flag when unwinding an OP_UNMAP_SPARSE

Official 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.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/a129b2b875c148aba233ace8447a0c36ca3bae07
• https://git.kernel.org/stable/c/196ce9e5e93202da097062be24e404984dbc5ac2
• https://git.kernel.org/stable/c/1101cbfe7f342e5eaaf7444965d4f1215abdac4c
• https://git.kernel.org/stable/c/c60033c172420179b7bbb3d1f843f8dc90164dc5
• https://git.kernel.org/stable/c/38a62306c4266bcb3cd89e33c7111ee33096ebb3