sd->devnode is released after calling v4l2_subdev_release. Therefore it should be set to NULL so that the subdev won't hold a pointer to a released object. This fixes a reference after free bug in function v4l2_device_unregister_subdev
Cc: stable@vger.kernel.org Fixes: 0e43734d4c46e ("media: v4l2-subdev: add release() internal op") Signed-off-by: Dafna Hirschfeld dafna.hirschfeld@collabora.com Reviewed-by: Ezequiel Garcia ezequiel@collabora.com --- changes since v2: - since this is a regresion fix, I added Fixes and Cc to stable tags, - change the commit title and log to be more clear.
drivers/media/v4l2-core/v4l2-device.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/media/v4l2-core/v4l2-device.c b/drivers/media/v4l2-core/v4l2-device.c index 63d6b147b21e..2b3595671d62 100644 --- a/drivers/media/v4l2-core/v4l2-device.c +++ b/drivers/media/v4l2-core/v4l2-device.c @@ -177,6 +177,7 @@ static void v4l2_subdev_release(struct v4l2_subdev *sd) { struct module *owner = !sd->owner_v4l2_dev ? sd->owner : NULL;
+ sd->devnode = NULL; if (sd->internal_ops && sd->internal_ops->release) sd->internal_ops->release(sd); module_put(owner);