From 322836160b7f2f38c397a2c3a0100b2ebeda65a2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Eduardo=20Leegwater=20Sim=C3=B5es?= <eduardo@dusk.network>
Date: Wed, 7 Feb 2024 17:16:00 +0100
Subject: [PATCH] piecrust: fix overflow in ICC gas limit calculation

---
 piecrust/CHANGELOG.md   | 4 ++++
 piecrust/src/imports.rs | 4 +++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/piecrust/CHANGELOG.md b/piecrust/CHANGELOG.md
index 715df6ce..f88fff6f 100644
--- a/piecrust/CHANGELOG.md
+++ b/piecrust/CHANGELOG.md
@@ -15,6 +15,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Upgrade `dusk-wasmtime` to version `17`
 
+### Fixed
+
+- Fix overflow in gas limit calculation in inter-contract call
+
 ## [0.15.0] - 2024-01-24
 
 ### Changed
diff --git a/piecrust/src/imports.rs b/piecrust/src/imports.rs
index 230036f1..51d6896c 100644
--- a/piecrust/src/imports.rs
+++ b/piecrust/src/imports.rs
@@ -209,7 +209,9 @@ pub(crate) fn c(
     let callee_limit = if gas_limit > 0 && gas_limit < caller_remaining {
         gas_limit
     } else {
-        caller_remaining * GAS_PASS_PCT / 100
+        let div = caller_remaining / 100 * GAS_PASS_PCT;
+        let rem = caller_remaining % 100 * GAS_PASS_PCT / 100;
+        div + rem
     };
 
     let with_memory = |memory: &mut [u8]| -> Result<_, Error> {