Index: uspace/srv/vfs/vfs_ops.c
===================================================================
--- uspace/srv/vfs/vfs_ops.c	(revision f63a591d1085b2ef35cde0f9ec4cb50fa2d4050e)
+++ uspace/srv/vfs/vfs_ops.c	(revision ef689ef0053c82c87f31cd2ea039a68dc6004d89)
@@ -1355,4 +1355,5 @@
 		int ret = vfs_close_internal(newfile);
 		if (ret != EOK) {
+			fibril_mutex_unlock(&oldfile->lock);
 			ipc_answer_0(rid, ret);
 			return;
@@ -1361,4 +1362,5 @@
 		ret = vfs_fd_free(newfd);
 		if (ret != EOK) {
+			fibril_mutex_unlock(&oldfile->lock);
 			ipc_answer_0(rid, ret);
 			return;