linux-kernel - [PATCH] drm/amd/display: Fix pointer dereferenced before checking

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:   Thu, 24 Mar 2022 17:27:14 +0800
From:   Haowen Bai <baihaowen@...zu.com>
To:     <harry.wentland@....com>, <sunpeng.li@....com>,
        <Rodrigo.Siqueira@....com>, <alexander.deucher@....com>,
        <christian.koenig@....com>, <Xinhui.Pan@....com>,
        <airlied@...ux.ie>, <daniel@...ll.ch>,
        <nicholas.kazlauskas@....com>, <lyude@...hat.com>,
        <Jerry.Zuo@....com>
CC:     <amd-gfx@...ts.freedesktop.org>, <dri-devel@...ts.freedesktop.org>,
        <linux-kernel@...r.kernel.org>, Haowen Bai <baihaowen@...zu.com>
Subject: [PATCH] drm/amd/display: Fix pointer dereferenced before checking

The pointer edid_buf is dereferencing pointer edid before edid is being
 null checked. Fix this by assigning edid->raw_edid to edid_buf only if 
edid is not NULL, otherwise just NULL.

Signed-off-by: Haowen Bai <baihaowen@...zu.com>
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
index 29f07c2..360401d 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
@@ -89,7 +89,7 @@ enum dc_edid_status dm_helpers_parse_edid_caps(
 {
 	struct amdgpu_dm_connector *aconnector = link->priv;
 	struct drm_connector *connector = &aconnector->base;
-	struct edid *edid_buf = (struct edid *) edid->raw_edid;
+	struct edid *edid_buf = edid ? (struct edid *) edid->raw_edid : NULL;
 	struct cea_sad *sads;
 	int sad_count = -1;
 	int sadb_count = -1;
-- 
2.7.4