diff --git a/include/linux/if_pppox.h b/include/linux/if_pppox.h
index 636772693f9a..594d6dc3f4c9 100644
--- a/include/linux/if_pppox.h
+++ b/include/linux/if_pppox.h
@@ -54,7 +54,7 @@ struct pppox_sock {
 
 static inline struct pppox_sock *pppox_sk(struct sock *sk)
 {
-	return (struct pppox_sock *)sk;
+	return container_of(sk, struct pppox_sock, sk);
 }
 
 struct module;