From 84577ce2c20fd6da30cfa935693850ffbdaebda4 Mon Sep 17 00:00:00 2001
From: Julian Oes <julian@oes.ch>
Date: Thu, 14 Jul 2022 08:40:49 +1200
Subject: [PATCH] battery: skip charge estimation if N cells is 0

This triggers the undefined behaviour fuzzer, so let's try to fix it.

Signed-off-by: Julian Oes <julian@oes.ch>
---
 src/lib/battery/battery.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/lib/battery/battery.cpp b/src/lib/battery/battery.cpp
index 122b4e69ba..4408754d1a 100644
--- a/src/lib/battery/battery.cpp
+++ b/src/lib/battery/battery.cpp
@@ -206,6 +206,10 @@ void Battery::sumDischarged(const hrt_abstime &timestamp, float current_a)
 
 float Battery::calculateStateOfChargeVoltageBased(const float voltage_v, const float current_a)
 {
+	if (_params.n_cells == 0) {
+		return -1.0f;
+	}
+
 	// remaining battery capacity based on voltage
 	float cell_voltage = voltage_v / _params.n_cells;