This fixes a NULL pointer dereference that can happen if the UDL
driver is unloaded before the framebuffer is initialized. This can
happen e.g. if the USB device is unplugged right after it was plugged
in.

Signed-off-by: Emil Lundmark <lnd...@chromium.org>
---
 drivers/gpu/drm/udl/udl_fb.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/udl/udl_fb.c b/drivers/gpu/drm/udl/udl_fb.c
index 2ebdc6d5a76e..5754e37f741b 100644
--- a/drivers/gpu/drm/udl/udl_fb.c
+++ b/drivers/gpu/drm/udl/udl_fb.c
@@ -426,9 +426,11 @@ static void udl_fbdev_destroy(struct drm_device *dev,
 {
        drm_fb_helper_unregister_fbi(&ufbdev->helper);
        drm_fb_helper_fini(&ufbdev->helper);
-       drm_framebuffer_unregister_private(&ufbdev->ufb.base);
-       drm_framebuffer_cleanup(&ufbdev->ufb.base);
-       drm_gem_object_put_unlocked(&ufbdev->ufb.obj->base);
+       if (ufbdev->ufb.obj) {
+               drm_framebuffer_unregister_private(&ufbdev->ufb.base);
+               drm_framebuffer_cleanup(&ufbdev->ufb.base);
+               drm_gem_object_put_unlocked(&ufbdev->ufb.obj->base);
+       }
 }
 
 int udl_fbdev_init(struct drm_device *dev)
-- 
2.17.0.484.g0c8726318c-goog

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Reply via email to