drm/tilcdc: fix leak & null ref in panel_connector_get_modes

[ 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@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429104234.18910-1-tomi.valkeinen@ti.com
Reviewed-by: Jyri Sarha <jsarha@ti.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/tilcdc/tilcdc_panel.c b/drivers/gpu/drm/tilcdc/tilcdc_panel.c
index 5584e656b8575822f9c76cb51ab2156cef0c904c..8c4fd1aa4c2dbf60e8a9241969f973762a1be536 100644 (file)
--- a/drivers/gpu/drm/tilcdc/tilcdc_panel.c
+++ b/drivers/gpu/drm/tilcdc/tilcdc_panel.c
@@ -143,12 +143,16 @@ 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;