drm/sun4i: Check return value of drm_vblank_init

drm_vblank_init can fail due to insufficient memory. Ignoring the error
and proceeding may cause the kernel to dereference an invalid pointer
when vblank is enabled.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

1 files changed, 5 insertions, 1 deletions

diff --git a/drivers/gpu/drm/sun4i/sun4i_drv.c b/drivers/gpu/drm/sun4i/sun4i_drv.c
index 7ae179e88309..46887c3044d0 100644
--- a/drivers/gpu/drm/sun4i/sun4i_drv.c
+++ b/drivers/gpu/drm/sun4i/sun4i_drv.c
@@ -102,7 +102,11 @@ static int sun4i_drv_bind(struct device *dev)
         }
         drm->dev_private = drv;
 
-        drm_vblank_init(drm, 1);
+        /* drm_vblank_init calls kcalloc, which can fail */
+        ret = drm_vblank_init(drm, 1);
+        if (ret)
+                goto free_drm;
+
         drm_mode_config_init(drm);
 
         ret = component_bind_all(drm->dev, drm);