diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 640fc22..168a80f 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -1358,6 +1358,10 @@
 	if (outarg.namelen > FUSE_NAME_MAX)
 		goto err;
 
+	err = -EINVAL;
+	if (size != sizeof(outarg) + outarg.namelen + 1)
+		goto err;
+
 	name.name = buf;
 	name.len = outarg.namelen;
 	err = fuse_copy_one(cs, buf, outarg.namelen + 1);