Author: Julia Lawall <Julia.Lawall@lip6.fr> for_each_child_of_node performs an of_node_get on each iteration, so a return from the middle of the loop requires an of_node_put. A simplified version of the semantic patch that finds this problem is as follows (http://coccinelle.lip6.fr): // @@ expression root,e; local idexpression child; @@ for_each_child_of_node(root, child) { … when != of_node_put(child) when != …