[PATCH] Gpu: drm: rockchip - Fix possible NULL derefrence.

From: Shailendra Verma
Date: Fri Jan 27 2017 - 06:42:05 EST


of_match_device could return NULL, and so can cause a NULL
pointer dereference later.

Signed-off-by: Shailendra Verma <shailendra.v@xxxxxxxxxxx>
---
drivers/gpu/drm/rockchip/dw-mipi-dsi.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
index ca22e5e..dbb99cf 100644
--- a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
+++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
@@ -1082,15 +1082,22 @@ static enum drm_mode_status rk3288_mipi_dsi_mode_valid(
static int dw_mipi_dsi_bind(struct device *dev, struct device *master,
void *data)
{
- const struct of_device_id *of_id =
- of_match_device(dw_mipi_dsi_dt_ids, dev);
- const struct dw_mipi_dsi_plat_data *pdata = of_id->data;
+ const struct of_device_id *of_id;
+ const struct dw_mipi_dsi_plat_data *pdata;
struct platform_device *pdev = to_platform_device(dev);
struct drm_device *drm = data;
struct dw_mipi_dsi *dsi;
struct resource *res;
int ret;

+ of_id = of_match_device(dw_mipi_dsi_dt_ids, dev);
+ if (!of_id) {
+ dev_err(dev, "Error: No device match found\n");
+ return -ENODEV;
+ }
+
+ pdata = of_id->data;
+
dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
if (!dsi)
return -ENOMEM;
--
1.7.9.5