From: Navid Emamdoost <navid.emamdoost@xxxxxxxxx> [ Upstream commit afd6d4f5a52c16e1483328ac074abb1cde92c29f ] The following function calls may fail and return NULL, so the null check is added. of_graph_get_next_endpoint of_graph_get_remote_port_parent of_graph_get_remote_port Update: Thanks to Sam Ravnborg, for suggession on the use of goto to avoid leaking endpoint. Signed-off-by: Navid Emamdoost <navid.emamdoost@xxxxxxxxx> Signed-off-by: Sam Ravnborg <sam@xxxxxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20190724195534.9303-1-navid.emamdoost@xxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- .../gpu/drm/panel/panel-raspberrypi-touchscreen.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c b/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c index 28c0620dfe0f9..b5b14aa059ea7 100644 --- a/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c +++ b/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c @@ -399,7 +399,13 @@ static int rpi_touchscreen_probe(struct i2c_client *i2c, /* Look up the DSI host. It needs to probe before we do. */ endpoint = of_graph_get_next_endpoint(dev->of_node, NULL); + if (!endpoint) + return -ENODEV; + dsi_host_node = of_graph_get_remote_port_parent(endpoint); + if (!dsi_host_node) + goto error; + host = of_find_mipi_dsi_host_by_node(dsi_host_node); of_node_put(dsi_host_node); if (!host) { @@ -408,6 +414,9 @@ static int rpi_touchscreen_probe(struct i2c_client *i2c, } info.node = of_graph_get_remote_port(endpoint); + if (!info.node) + goto error; + of_node_put(endpoint); ts->dsi = mipi_dsi_device_register_full(host, &info); @@ -428,6 +437,10 @@ static int rpi_touchscreen_probe(struct i2c_client *i2c, return ret; return 0; + +error: + of_node_put(endpoint); + return -ENODEV; } static int rpi_touchscreen_remove(struct i2c_client *i2c) -- 2.20.1