| From 4d906839d321c2efbf3fed4bc31ffd9ff55b75c0 Mon Sep 17 00:00:00 2001 |
| From: Paul Cercueil <paul@crapouillou.net> |
| Date: Sat, 27 Mar 2021 11:57:40 +0000 |
| Subject: drm: bridge/panel: Cleanup connector on bridge detach |
| |
| From: Paul Cercueil <paul@crapouillou.net> |
| |
| commit 4d906839d321c2efbf3fed4bc31ffd9ff55b75c0 upstream. |
| |
| 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: <stable@vger.kernel.org> # 4.12+ |
| Cc: Andrzej Hajda <a.hajda@samsung.com> |
| Cc: Neil Armstrong <narmstrong@baylibre.com> |
| Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com> |
| Cc: Jonas Karlman <jonas@kwiboo.se> |
| Cc: Jernej Skrabec <jernej.skrabec@siol.net> |
| Signed-off-by: Paul Cercueil <paul@crapouillou.net> |
| Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> |
| Link: https://patchwork.freedesktop.org/patch/msgid/20210327115742.18986-2-paul@crapouillou.net |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/gpu/drm/bridge/panel.c | 12 ++++++++++++ |
| 1 file changed, 12 insertions(+) |
| |
| --- a/drivers/gpu/drm/bridge/panel.c |
| +++ b/drivers/gpu/drm/bridge/panel.c |
| @@ -87,6 +87,18 @@ static int panel_bridge_attach(struct dr |
| |
| 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) |