RDMA/uverbs: Ensure validity of current QP state value

The QP state is internal enum which is checked at the driver
level by calling to ib_modify_qp_is_ok(). Move this check closer
to user and leave kernel users to be checked by compiler.
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/core/uverbs_cmd.c

@@ -1991,6 +1991,13 @@ static int modify_qp(struct ib_uverbs_file *file,
 		goto release_qp;
 	}
 
+	if ((cmd->base.attr_mask & IB_QP_CUR_STATE &&
+	    cmd->base.cur_qp_state > IB_QPS_ERR) ||
+	    cmd->base.qp_state > IB_QPS_ERR) {
+		ret = -EINVAL;
+		goto release_qp;
+	}
+
 	attr->qp_state		  = cmd->base.qp_state;
 	attr->cur_qp_state	  = cmd->base.cur_qp_state;
 	attr->path_mtu		  = cmd->base.path_mtu;