[Nouveau] [RFC] gem: fix "refcount_t: underflow; use-after-free"

[Karol Herbst]

we can't use nouveau_bo_ref here as no ttm object was allocated and
nouveau_bo_ref mainly deals with that. Simply deallocate the object.

Signed-off-by: Karol Herbst <kherbst at redhat.com>
---
 drm/nouveau/nouveau_gem.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drm/nouveau/nouveau_gem.c b/drm/nouveau/nouveau_gem.c
index e11303fbc..45582a8dc 100644
--- a/drm/nouveau/nouveau_gem.c
+++ b/drm/nouveau/nouveau_gem.c
@@ -198,7 +198,8 @@ nouveau_gem_new(struct nouveau_cli *cli, u64 size, int align, uint32_t domain,
 	 * to the caller, instead of a normal nouveau_bo ttm reference. */
 	ret = drm_gem_object_init(drm->dev, &nvbo->bo.base, size);
 	if (ret) {
-		nouveau_bo_ref(NULL, &nvbo);
+		drm_gem_object_release(&nvbo->bo.base);
+		kfree(nvbo);
 		return ret;
 	}
 
-- 
2.26.2