diff --git a/lib/io.c b/lib/io.c
index 50426d556..3beb6f114 100644
--- a/lib/io.c
+++ b/lib/io.c
@@ -332,7 +332,7 @@ int io_open(struct io *io, const char *uri)
 {
 	int ret;
 
-	assert(io->state == STATE_CHECKED);
+	assert(io->state == STATE_CHECKED || io->state == STATE_CLOSED);
 
 	ret = io_type(io)->open
 		? io_type(io)->open(io, uri)