Add error handling to check NULL input in
mtk_drm_crtc_dma_dev_get function.
While display path is not configured correctly, none of crtc is
established. So the caller of mtk_drm_crtc_dma_dev_get may pass
input parameter *crtc as NULL, Which may cause coredump when
we try to get the container of NULL pointer.
Fixes: cb1d6bcca542 ("drm/mediatek: Add dma dev get function")
Signed-off-by: Stuart Lee <stuart.lee@xxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
index c277b9fae950..047c9a31d306 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
@@ -921,7 +921,14 @@ static int mtk_drm_crtc_init_comp_planes(struct drm_device *drm_dev,
struct device *mtk_drm_crtc_dma_dev_get(struct drm_crtc *crtc)
{
- struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
+ struct mtk_drm_crtc *mtk_crtc = NULL;
+
+ if (!crtc)
+ return NULL;
+
+ mtk_crtc = to_mtk_crtc(crtc);
+ if (!mtk_crtc)
+ return NULL;
return mtk_crtc->dma_dev;
}
--
2.18.0
