linux-kernel - [PATCH 1/1] drm/vmwgfx: avoid possible NULL pointer dereference

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>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1471814177-5472-1-git-send-email-xypron.glpk@gmx.de>
Date:   Sun, 21 Aug 2016 23:16:17 +0200
From:   Heinrich Schuchardt <xypron.glpk@....de>
To:     VMware Graphics <linux-graphics-maintainer@...are.com>,
        Sinclair Yeh <syeh@...are.com>,
        Thomas Hellstrom <thellstrom@...are.com>,
        David Airlie <airlied@...ux.ie>
Cc:     dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org,
        Heinrich Schuchardt <xypron.glpk@....de>
Subject: [PATCH 1/1] drm/vmwgfx: avoid possible NULL pointer dereference

The comment describing function vmw_cmd_res_reloc_add
explicitely mentions p_val may be NULL.

We should not assign a value (NULL) to *p_val in this case.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@....de>
---
 drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
index dc5beff..0363989 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
@@ -652,7 +652,11 @@ static int vmw_cmd_res_reloc_add(struct vmw_private *dev_priv,
 	int ret;
 	struct vmw_resource_val_node *node;
 
+	if (!p_val)
+		return;
+
 	*p_val = NULL;
+
 	ret = vmw_resource_relocation_add(&sw_context->res_relocations,
 					  res,
 					  id_loc - sw_context->buf_start);
@@ -663,8 +667,7 @@ static int vmw_cmd_res_reloc_add(struct vmw_private *dev_priv,
 	if (unlikely(ret != 0))
 		return ret;
 
-	if (p_val)
-		*p_val = node;
+	*p_val = node;
 
 	return 0;
 }
-- 
2.1.4