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From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Liang He <windhl@126.com>,
        Martin Blumenstingl <martin.blumenstingl@googlemail.com>,
        Neil Armstrong <narmstrong@baylibre.com>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.19 257/287] drm/meson: Fix refcount bugs in meson_vpu_has_available_connectors()
Date:   Tue, 23 Aug 2022 10:27:06 +0200
Message-Id: <20220823080109.922330877@linuxfoundation.org>
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From: Liang He <windhl@126.com>

[ Upstream commit 91b3c8dbe898df158fd2a84675f3a284ff6666f7 ]

In this function, there are two refcount leak bugs:
(1) when breaking out of for_each_endpoint_of_node(), we need call
the of_node_put() for the 'ep';
(2) we should call of_node_put() for the reference returned by
of_graph_get_remote_port() when it is not used anymore.

Fixes: bbbe775ec5b5 ("drm: Add support for Amlogic Meson Graphic Controller")
Signed-off-by: Liang He <windhl@126.com>
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220726010722.1319416-1-windhl@126.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/meson/meson_drv.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/meson/meson_drv.c b/drivers/gpu/drm/meson/meson_drv.c
index 1887473cdd79..9959522ce802 100644
--- a/drivers/gpu/drm/meson/meson_drv.c
+++ b/drivers/gpu/drm/meson/meson_drv.c
@@ -141,8 +141,11 @@ static bool meson_vpu_has_available_connectors(struct device *dev)
 	for_each_endpoint_of_node(dev->of_node, ep) {
 		/* If the endpoint node exists, consider it enabled */
 		remote = of_graph_get_remote_port(ep);
-		if (remote)
+		if (remote) {
+			of_node_put(remote);
+			of_node_put(ep);
 			return true;
+		}
 	}
 
 	return false;
-- 
2.35.1