diff --git a/ipc/sem.c b/ipc/sem.c
index 87c2b64..2f2a479 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -129,6 +129,7 @@
 void sem_exit_ns(struct ipc_namespace *ns)
 {
 	free_ipcs(ns, &sem_ids(ns), freeary);
+	idr_destroy(&ns->ids[IPC_SEM_IDS].ipcs_idr);
 }
 #endif