[PATCH] drm, video: fix use-before-NULL-check

From: Kees Cook
Date: Fri Aug 27 2010 - 17:07:57 EST


Fix potential crashes due to use-before-NULL situations.

Signed-off-by: Kees Cook <kees.cook@xxxxxxxxxxxxx>
---
drivers/gpu/drm/drm_fb_helper.c | 3 ++-
drivers/media/video/em28xx/em28xx-video.c | 3 ++-
2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index de82e20..8dd7e6f 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -94,10 +94,11 @@ static bool drm_fb_helper_connector_parse_command_line(struct drm_fb_helper_conn
int i;
enum drm_connector_force force = DRM_FORCE_UNSPECIFIED;
struct drm_fb_helper_cmdline_mode *cmdline_mode;
- struct drm_connector *connector = fb_helper_conn->connector;
+ struct drm_connector *connector;

if (!fb_helper_conn)
return false;
+ connector = fb_helper_conn->connector;

cmdline_mode = &fb_helper_conn->cmdline_mode;
if (!mode_option)
diff --git a/drivers/media/video/em28xx/em28xx-video.c b/drivers/media/video/em28xx/em28xx-video.c
index 7b9ec6e..95a4b60 100644
--- a/drivers/media/video/em28xx/em28xx-video.c
+++ b/drivers/media/video/em28xx/em28xx-video.c
@@ -277,12 +277,13 @@ static void em28xx_copy_vbi(struct em28xx *dev,
{
void *startwrite, *startread;
int offset;
- int bytesperline = dev->vbi_width;
+ int bytesperline;

if (dev == NULL) {
em28xx_isocdbg("dev is null\n");
return;
}
+ bytesperline = dev->vbi_width;

if (dma_q == NULL) {
em28xx_isocdbg("dma_q is null\n");
--
1.7.1


--
Kees Cook
Ubuntu Security Team
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/