[PATCH 4.19 077/245] drm/omap: fix possible object reference leak

From: Greg Kroah-Hartman
Date: Tue Sep 29 2020 - 07:33:56 EST


From: Wen Yang <wen.yang99@xxxxxxxxxx>

[ Upstream commit 47340e46f34a3b1d80e40b43ae3d7a8da34a3541 ]

The call to of_find_matching_node 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/omapdrm/dss/omapdss-boot-init.c:212:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 209, but without a corresponding object release within this function.
drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c:237:1-7: 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>
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
Reviewed-by: Mukesh Ojha <mojha@xxxxxxxxxxxxxx>
Cc: Tomi Valkeinen <tomi.valkeinen@xxxxxx>
Cc: David Airlie <airlied@xxxxxxxx>
Cc: Daniel Vetter <daniel@xxxxxxxx>
Cc: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxx>
Cc: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: Markus Elfring <Markus.Elfring@xxxxxx>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/1554692313-28882-2-git-send-email-wen.yang99@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c b/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
index 3bfb95d230e0e..d8fb686c1fda9 100644
--- a/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
+++ b/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
@@ -193,7 +193,7 @@ static int __init omapdss_boot_init(void)
dss = of_find_matching_node(NULL, omapdss_of_match);

if (dss == NULL || !of_device_is_available(dss))
- return 0;
+ goto put_node;

omapdss_walk_device(dss, true);

@@ -218,6 +218,8 @@ static int __init omapdss_boot_init(void)
kfree(n);
}

+put_node:
+ of_node_put(dss);
return 0;
}

--
2.25.1