From 4d906839d321c2efbf3fed4bc31ffd9ff55b75c0 Mon Sep 17 00:00:00 2001 From: Paul Cercueil Date: Sat, 27 Mar 2021 11:57:40 +0000 Subject: [PATCH] drm: bridge/panel: Cleanup connector on bridge detach If we don't call drm_connector_cleanup() manually in panel_bridge_detach(), the connector will be cleaned up with the other DRM objects in the call to drm_mode_config_cleanup(). However, since our drm_connector is devm-allocated, by the time drm_mode_config_cleanup() will be called, our connector will be long gone. Therefore, the connector must be cleaned up when the bridge is detached to avoid use-after-free conditions. v2: Cleanup connector only if it was created v3: Add FIXME v4: (Use connector->dev) directly in if() block Fixes: 13dfc0540a57 ("drm/bridge: Refactor out the panel wrapper from the lvds-encoder bridge.") Cc: # 4.12+ Cc: Andrzej Hajda Cc: Neil Armstrong Cc: Laurent Pinchart Cc: Jonas Karlman Cc: Jernej Skrabec Signed-off-by: Paul Cercueil Reviewed-by: Laurent Pinchart Link: https://patchwork.freedesktop.org/patch/msgid/20210327115742.18986-2-paul@crapouillou.net --- drivers/gpu/drm/bridge/panel.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/gpu/drm/bridge/panel.c b/drivers/gpu/drm/bridge/panel.c index 0ddc37551194..c916f4b8907e 100644 --- a/drivers/gpu/drm/bridge/panel.c +++ b/drivers/gpu/drm/bridge/panel.c @@ -87,6 +87,18 @@ static int panel_bridge_attach(struct drm_bridge *bridge, static void panel_bridge_detach(struct drm_bridge *bridge) { + struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge); + struct drm_connector *connector = &panel_bridge->connector; + + /* + * Cleanup the connector if we know it was initialized. + * + * FIXME: This wouldn't be needed if the panel_bridge structure was + * allocated with drmm_kzalloc(). This might be tricky since the + * drm_device pointer can only be retrieved when the bridge is attached. + */ + if (connector->dev) + drm_connector_cleanup(connector); } static void panel_bridge_pre_enable(struct drm_bridge *bridge) -- 2.34.1