From 6168dd8ab3855b1d24c733008265d7c0ca8534e4 Mon Sep 17 00:00:00 2001
From: Csongor Kiss <kiss.csongor.kiss@gmail.com>
Date: Thu, 24 Aug 2023 17:58:38 +0100
Subject: [PATCH] near/contracts: clamp upgrade repayment delta to 0

This ensures that the refund amount is at most the attached deposit when
upgrading the contract.
---
 near/contracts/nft-bridge/src/lib.rs   | 4 ++++
 near/contracts/token-bridge/src/lib.rs | 4 ++++
 near/contracts/wormhole/src/lib.rs     | 4 ++++
 3 files changed, 12 insertions(+)

diff --git a/near/contracts/nft-bridge/src/lib.rs b/near/contracts/nft-bridge/src/lib.rs
index 5132eb184..e9f14e457 100644
--- a/near/contracts/nft-bridge/src/lib.rs
+++ b/near/contracts/nft-bridge/src/lib.rs
@@ -48,6 +48,8 @@ use {
 pub mod byte_utils;
 pub mod state;
 
+use std::cmp::max;
+
 use crate::byte_utils::{
     get_string_from_32,
     ByteUtils,
@@ -791,6 +793,8 @@ impl NFTBridge {
     ) {
         let delta = (env::storage_usage() as i128 - storage_used as i128)
             * env::storage_byte_cost() as i128;
+        let delta = max(0, delta);
+
         let refund = attached_deposit as i128 - delta;
         if refund > 0 {
             env::log_str(&format!(
diff --git a/near/contracts/token-bridge/src/lib.rs b/near/contracts/token-bridge/src/lib.rs
index 8caa36083..ec9095f93 100644
--- a/near/contracts/token-bridge/src/lib.rs
+++ b/near/contracts/token-bridge/src/lib.rs
@@ -40,6 +40,8 @@ use {
 pub mod byte_utils;
 pub mod state;
 
+use std::cmp::max;
+
 use crate::byte_utils::{
     get_string_from_32,
     ByteUtils,
@@ -1709,6 +1711,8 @@ impl TokenBridge {
         ));
         let delta = (env::storage_usage() as i128 - storage_used as i128)
             * env::storage_byte_cost() as i128;
+        let delta = max(0, delta);
+
         let refund = attached_deposit as i128 - delta;
         if refund > 0 {
             env::log_str(&format!(
diff --git a/near/contracts/wormhole/src/lib.rs b/near/contracts/wormhole/src/lib.rs
index 1e4af31cf..d405c0d5a 100644
--- a/near/contracts/wormhole/src/lib.rs
+++ b/near/contracts/wormhole/src/lib.rs
@@ -26,6 +26,8 @@ pub mod byte_utils;
 
 pub mod state;
 
+use std::cmp::max;
+
 use crate::byte_utils::{
     get_string_from_32,
     ByteUtils,
@@ -582,6 +584,8 @@ impl Wormhole {
     ) {
         let delta = (env::storage_usage() as i128 - storage_used as i128)
             * env::storage_byte_cost() as i128;
+        let delta = max(0, delta);
+
         let refund = attached_deposit as i128 - delta;
         if refund > 0 {
             env::log_str(&format!(