If the subdev did not define any controls, then return -ENOTTY if userspace attempts to call these ioctls. The control framework functions will return -EINVAL, not -ENOTTY if vfh->ctrl_handler is NULL. Several of these framework functions are also called directly from drivers, so I don't want to change the error code there. Found with vimc and v4l2-compliance. Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx> Acked-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> --- drivers/media/v4l2-core/v4l2-subdev.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c index c5639817db34..b14c5e1705ca 100644 --- a/drivers/media/v4l2-core/v4l2-subdev.c +++ b/drivers/media/v4l2-core/v4l2-subdev.c @@ -187,27 +187,51 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg) switch (cmd) { case VIDIOC_QUERYCTRL: + /* + * TODO: this really should be folded into v4l2_queryctrl (this + * currently returns -EINVAL for NULL control handlers). + * However, v4l2_queryctrl() is still called directly by + * drivers as well and until that has been addressed I believe + * it is safer to do the check here. The same is true for the + * other control ioctls below. + */ + if (!vfh->ctrl_handler) + return -ENOTTY; return v4l2_queryctrl(vfh->ctrl_handler, arg); case VIDIOC_QUERY_EXT_CTRL: + if (!vfh->ctrl_handler) + return -ENOTTY; return v4l2_query_ext_ctrl(vfh->ctrl_handler, arg); case VIDIOC_QUERYMENU: + if (!vfh->ctrl_handler) + return -ENOTTY; return v4l2_querymenu(vfh->ctrl_handler, arg); case VIDIOC_G_CTRL: + if (!vfh->ctrl_handler) + return -ENOTTY; return v4l2_g_ctrl(vfh->ctrl_handler, arg); case VIDIOC_S_CTRL: + if (!vfh->ctrl_handler) + return -ENOTTY; return v4l2_s_ctrl(vfh, vfh->ctrl_handler, arg); case VIDIOC_G_EXT_CTRLS: + if (!vfh->ctrl_handler) + return -ENOTTY; return v4l2_g_ext_ctrls(vfh->ctrl_handler, arg); case VIDIOC_S_EXT_CTRLS: + if (!vfh->ctrl_handler) + return -ENOTTY; return v4l2_s_ext_ctrls(vfh, vfh->ctrl_handler, arg); case VIDIOC_TRY_EXT_CTRLS: + if (!vfh->ctrl_handler) + return -ENOTTY; return v4l2_try_ext_ctrls(vfh->ctrl_handler, arg); case VIDIOC_DQEVENT: -- 2.16.1