[PATCH v2] drm: rcar-du: fix possible object reference leak

From: Wen Yang
Date: Sun Apr 07 2019 - 22:58:18 EST


The call to of_get_parent returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.

Detected by coccinelle with the following warnings:
drivers/gpu/drm/rcar-du/rcar_du_of.c:235:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 216, but without a corresponding object release within this function.
drivers/gpu/drm/rcar-du/rcar_du_of.c:236:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 209, but without a corresponding object release within this function.

Signed-off-by: Wen Yang <wen.yang99@xxxxxxxxxx>
Suggested-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
Cc: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
Cc: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
Cc: David Airlie <airlied@xxxxxxxx>
Cc: Daniel Vetter <daniel@xxxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: linux-renesas-soc@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx (open list)
---
v2->v1: turn the return into a goto done.

drivers/gpu/drm/rcar-du/rcar_du_of.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/rcar-du/rcar_du_of.c b/drivers/gpu/drm/rcar-du/rcar_du_of.c
index afef696..782bfc7 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_of.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_of.c
@@ -232,7 +232,7 @@ static void __init rcar_du_of_lvds_patch(const struct of_device_id *of_ids)
lvds_node = of_find_compatible_node(NULL, NULL, compatible);
if (lvds_node) {
of_node_put(lvds_node);
- return;
+ goto done;
}

/*
--
2.9.5