From: "benjamin.gaignard@linaro.org" <benjamin.gaignard@linaro.org>
Date: Mon, 2 Oct 2017 11:32:31 +0200
Subject: drm/bridge: make drm_panel_bridge_remove more robust
Git-commit: 6b0e284cfa3898109f9f4c9fa6541caa027a3635
Patch-mainline: v4.15-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166
Make sure that bridge parameter is not NULL and can be safely
cast into a panel_bridge structure.
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Reviewed-by: Philippe Cornu <philippe.cornu@st.com>
Tested-by: Philippe Cornu <philippe.cornu@st.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1506936755-23625-2-git-send-email-benjamin.gaignard@linaro.org
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
drivers/gpu/drm/bridge/panel.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
--- a/drivers/gpu/drm/bridge/panel.c
+++ b/drivers/gpu/drm/bridge/panel.c
@@ -188,7 +188,15 @@ EXPORT_SYMBOL(drm_panel_bridge_add);
*/
void drm_panel_bridge_remove(struct drm_bridge *bridge)
{
- struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
+ struct panel_bridge *panel_bridge;
+
+ if (!bridge)
+ return;
+
+ if (bridge->funcs != &panel_bridge_bridge_funcs)
+ return;
+
+ panel_bridge = drm_bridge_to_panel_bridge(bridge);
drm_bridge_remove(bridge);
devm_kfree(panel_bridge->panel->dev, bridge);