From: Min Li lm0963hack@gmail.com
[ Upstream commit 48bfd02569f5db49cc033f259e66d57aa6efc9a3 ]
If it is async, runqueue_node is freed in g2d_runqueue_worker on another worker thread. So in extreme cases, if g2d_runqueue_worker runs first, and then executes the following if statement, there will be use-after-free.
Signed-off-by: Min Li lm0963hack@gmail.com Reviewed-by: Andi Shyti andi.shyti@kernel.org Signed-off-by: Inki Dae inki.dae@samsung.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/exynos/exynos_drm_g2d.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/exynos/exynos_drm_g2d.c b/drivers/gpu/drm/exynos/exynos_drm_g2d.c index f2481a2014bb3..2b7ecc02b2774 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_g2d.c +++ b/drivers/gpu/drm/exynos/exynos_drm_g2d.c @@ -1327,7 +1327,7 @@ int exynos_g2d_exec_ioctl(struct drm_device *drm_dev, void *data, /* Let the runqueue know that there is work to do. */ queue_work(g2d->g2d_workq, &g2d->runqueue_work);
- if (runqueue_node->async) + if (req->async) goto out;
wait_for_completion(&runqueue_node->complete);