[PATCH 5.10 328/390] gpu: lontium-lt9611: Fix NULL pointer dereference in lt9611_connector_init()

From: Greg Kroah-Hartman
Date: Mon Oct 24 2022 - 11:58:29 EST


From: Zeng Jingxiang <linuszeng@xxxxxxxxxxx>

[ Upstream commit ef8886f321c5dab8124b9153d25afa2a71d05323 ]

A NULL check for bridge->encoder shows that it may be NULL, but it
already been dereferenced on all paths leading to the check.
812 if (!bridge->encoder) {

Dereference the pointer bridge->encoder.
810 drm_connector_attach_encoder(&lt9611->connector, bridge->encoder);

Signed-off-by: Zeng Jingxiang <linuszeng@xxxxxxxxxxx>
Signed-off-by: Robert Foss <robert.foss@xxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20220727073119.1578972-1-zengjx95@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/bridge/lontium-lt9611.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/lontium-lt9611.c b/drivers/gpu/drm/bridge/lontium-lt9611.c
index 29b1ce2140ab..1dcc28a4d853 100644
--- a/drivers/gpu/drm/bridge/lontium-lt9611.c
+++ b/drivers/gpu/drm/bridge/lontium-lt9611.c
@@ -816,13 +816,14 @@ static int lt9611_connector_init(struct drm_bridge *bridge, struct lt9611 *lt961

drm_connector_helper_add(&lt9611->connector,
&lt9611_bridge_connector_helper_funcs);
- drm_connector_attach_encoder(&lt9611->connector, bridge->encoder);

if (!bridge->encoder) {
DRM_ERROR("Parent encoder object not found");
return -ENODEV;
}

+ drm_connector_attach_encoder(&lt9611->connector, bridge->encoder);
+
return 0;
}

--
2.35.1