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…a config save HwTools::setup() runs after every web UI save that does not require a restart, and it clears tempSensorInit. The next updateTemperatures() then enters the init branch again with sensorCount still set from the previous run: it deletes the tempSensors array and immediately searches it for matching addresses, dereferencing freed memory. On ESP8266 this shows up as an exception 28 (LoadProhibited) in isSensorAddressEqual() on the first temperature read after saving, e.g. changing MQTT settings on a device with a DS18B20 attached. Keep the old array alive while matching, move surviving entries into the new array, and free the rest. Also use delete[] for the array.
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Problem
HwTools::setup()runs after every web UI save that does not require a restart (seeAmsWebServer::handleSave), and it clearstempSensorInit. The nextupdateTemperatures()therefore enters the init branch again whilesensorCountis still set from the previous run. That branch deleted thetempSensorsarray and then searched it for matching addresses, dereferencing freed memory.On ESP8266 this reproduces as an exception 28 (LoadProhibited) in
isSensorAddressEqual()on the first temperature read after saving, for example after changing MQTT settings on a device with a DS18B20 attached. Stack from the crash:Fix
Keep the old array alive while matching addresses, move surviving entries into the new array, free entries for sensors that are gone, and use
delete[]for the array.Tested
ESP8266 (D1 mini), one DS18B20 on GPIO14, v2.5.7 and current main. Saving MQTT settings crashed the device every time before; after the fix the save completes and the sensor keeps reporting.