[PATCH 3/7] drm/sun4i: Check return value of drm_vblank_init

From: Chen-Yu Tsai
Date: Thu Feb 16 2017 - 22:13:49 EST


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@xxxxxxxx>
---
drivers/gpu/drm/sun4i/sun4i_drv.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/sun4i/sun4i_drv.c b/drivers/gpu/drm/sun4i/sun4i_drv.c
index 8e777167bca4..63c46643fdd1 100644
--- a/drivers/gpu/drm/sun4i/sun4i_drv.c
+++ b/drivers/gpu/drm/sun4i/sun4i_drv.c
@@ -130,7 +130,11 @@ 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);
--
2.11.0