From fe6509a0f2f07661b38bccbcd765ed9612e493c1 Mon Sep 17 00:00:00 2001 From: Dirk Mueller Date: Mon, 13 Oct 2025 13:57:21 +0200 Subject: [PATCH] Avoid exceeding allocated buffers when doing MQTT proxying (#8320) the topic length could be longer than 65 characters. similarly for the payload. Co-authored-by: Ben Meadors --- src/mqtt/MQTT.cpp | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/src/mqtt/MQTT.cpp b/src/mqtt/MQTT.cpp index 8ce352f14..33887557f 100644 --- a/src/mqtt/MQTT.cpp +++ b/src/mqtt/MQTT.cpp @@ -473,7 +473,9 @@ bool MQTT::publish(const char *topic, const uint8_t *payload, size_t length, boo if (moduleConfig.mqtt.proxy_to_client_enabled) { meshtastic_MqttClientProxyMessage *msg = mqttClientProxyMessagePool.allocZeroed(); msg->which_payload_variant = meshtastic_MqttClientProxyMessage_data_tag; - strcpy(msg->topic, topic); + strlcpy(msg->topic, topic, sizeof(msg->topic)); + if (length > sizeof(msg->payload_variant.data.bytes)) + length = sizeof(msg->payload_variant.data.bytes); msg->payload_variant.data.size = length; memcpy(msg->payload_variant.data.bytes, payload, length); msg->retained = retained;