[PATCH 4.14 060/228] drm/tilcdc: fix leak & null ref in panel_connector_get_modes

From: Greg Kroah-Hartman
Date: Thu Aug 20 2020 - 07:08:51 EST


From: Tomi Valkeinen <tomi.valkeinen@xxxxxx>

[ Upstream commit 3f9c1c872cc97875ddc8d63bc9fe6ee13652b933 ]

If videomode_from_timings() returns true, the mode allocated with
drm_mode_create will be leaked.

Also, the return value of drm_mode_create() is never checked, and thus
could cause NULL deref.

Fix these two issues.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429104234.18910-1-tomi.valkeinen@xxxxxx
Reviewed-by: Jyri Sarha <jsarha@xxxxxx>
Acked-by: Sam Ravnborg <sam@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/tilcdc/tilcdc_panel.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/tilcdc/tilcdc_panel.c b/drivers/gpu/drm/tilcdc/tilcdc_panel.c
index 1813a3623ce60..0484b2cf0e2b5 100644
--- a/drivers/gpu/drm/tilcdc/tilcdc_panel.c
+++ b/drivers/gpu/drm/tilcdc/tilcdc_panel.c
@@ -152,12 +152,16 @@ static int panel_connector_get_modes(struct drm_connector *connector)
int i;

for (i = 0; i < timings->num_timings; i++) {
- struct drm_display_mode *mode = drm_mode_create(dev);
+ struct drm_display_mode *mode;
struct videomode vm;

if (videomode_from_timings(timings, &vm, i))
break;

+ mode = drm_mode_create(dev);
+ if (!mode)
+ break;
+
drm_display_mode_from_videomode(&vm, mode);

mode->type = DRM_MODE_TYPE_DRIVER;
--
2.25.1