linux-kernel - [PATCH] drm: of: fix leak of endpoint

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <20200925224447.GA27832@agrajag.zerfleddert.de>
Date:   Sat, 26 Sep 2020 00:44:47 +0200
From:   Tobias Jordan <kernel@...e.de>
To:     dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org
Cc:     Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
        Maxime Ripard <mripard@...nel.org>,
        Thomas Zimmermann <tzimmermann@...e.de>,
        David Airlie <airlied@...ux.ie>,
        Daniel Vetter <daniel@...ll.ch>,
        Laurent Pinchart <laurent.pinchart@...asonboard.com>,
        Fabrizio Castro <fabrizio.castro@...renesas.com>
Subject: [PATCH] drm: of: fix leak of endpoint

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 endpoint
and also the first error path which was obviously wrong as well.

Fix the leak of endpoint in the error path 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@...e.de>
---
Sorry for the confusion, it seems it's not that easy to get the variable
name right. Please disregard the patch sent a few minutes ago, this is
the right one.

 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..997b8827fed2 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(endpoint);
 			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(endpoint);
 			return -EINVAL;
+		}
 	}
 
 	return pixels_type;
-- 
2.20.1