diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h
index 58165928ed1e..3baccd4143e8 100644
--- a/fs/ecryptfs/ecryptfs_kernel.h
+++ b/fs/ecryptfs/ecryptfs_kernel.h
@@ -124,6 +124,9 @@ ecryptfs_get_key_payload_data(struct key *key)
 	if (!ukp)
 		return ERR_PTR(-EKEYREVOKED);
 
+	if (ukp->datalen < sizeof(struct ecryptfs_auth_tok))
+		return ERR_PTR(-EINVAL);
+
 	return (struct ecryptfs_auth_tok *)ukp->data;
 }