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Date:   Sat, 26 Sep 2020 00:37:00 +0200
From:   Tobias Jordan <kernel@cdqe.de>
To:     dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
Cc:     Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Subject: [PATCH] drm: of: fix leak of port_node
Message-ID: <20200925223700.GA26659@agrajag.zerfleddert.de>
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User-Agent: Mutt/1.10.1 (2018-07-13)
Precedence: bulk

The for_each_child_of_node loop in drm_of_lvds_get_remote_pixels_type
bails out in two occasions. Originally, both were calling of_node_put to
clean up, but (probably a typo) for the wrong variable.

One of these typos was fixed in commit 4ee48cc5586b ("drm: of: Fix
double-free bug"), but that missed the leak of the original port_node
and also the first error path which was obviously wrong as well.

Fix the leak of port_node in the error paths by calling of_node_put on
it.

Fixes: 6529007522de ("drm: of: Add drm_of_lvds_get_dual_link_pixel_order")
Signed-off-by: Tobias Jordan <kernel@cdqe.de>
---
 drivers/gpu/drm/drm_of.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c
index ca04c34e8251..5c136bd5a671 100644
--- a/drivers/gpu/drm/drm_of.c
+++ b/drivers/gpu/drm/drm_of.c
@@ -315,7 +315,7 @@ static int drm_of_lvds_get_remote_pixels_type(
 
 		remote_port = of_graph_get_remote_port(endpoint);
 		if (!remote_port) {
-			of_node_put(remote_port);
+			of_node_put(port_node);
 			return -EPIPE;
 		}
 
@@ -331,8 +331,10 @@ static int drm_of_lvds_get_remote_pixels_type(
 		 * configurations by passing the endpoints explicitly to
 		 * drm_of_lvds_get_dual_link_pixel_order().
 		 */
-		if (!current_pt || pixels_type != current_pt)
+		if (!current_pt || pixels_type != current_pt) {
+			of_node_put(port_node);
 			return -EINVAL;
+		}
 	}
 
 	return pixels_type;
-- 
2.20.1