drm/nouveau: fix null pointer dereference in nouveau_connector_get_modes

In nouveau_connector_get_modes(), the return value of drm_mode_duplicate()
is assigned to mode, which will lead to a possible NULL pointer
dereference on failure of drm_mode_duplicate(). Add a check to avoid npd.

Cc: stable@vger.kernel.org
Fixes: 6ee738610f41 ("drm/nouveau: Add DRM driver for NVIDIA GPUs")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240627074204.3023776-1-make24@iscas.ac.cn

diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c
index 856b3ef5edb89f109e26095c72b92115a8ddba54..0c71d761d37850dfcc91a5b613757a94541ae5ac 100644 (file)
--- a/drivers/gpu/drm/nouveau/nouveau_connector.c
+++ b/drivers/gpu/drm/nouveau/nouveau_connector.c
@@ -1001,6 +1001,9 @@ nouveau_connector_get_modes(struct drm_connector *connector)
                struct drm_display_mode *mode;
 
                mode = drm_mode_duplicate(dev, nv_connector->native_mode);
+               if (!mode)
+                       return 0;
+
                drm_mode_probed_add(connector, mode);
                ret = 1;
        }