Don't handle packets from clients we're closing

This should prevent stale data from old clients from manipulating the session.

Don't handle packets from clients we're closing
This should prevent stale data from old clients from manipulating the session.
Wiebe Cazemier
1 parent d125dc49
Showing 2 changed files with 6 additions and 0 deletions
client.h
mqttpacket.cpp
@@ -134,6 +134,7 @@ public:
     int writeMqttPacketAndBlameThisClient(PublishCopyFactory &copyFactory, char max_qos, uint16_t packet_id);
     int writeMqttPacketAndBlameThisClient(const MqttPacket &packet);
     bool writeBufIntoFd();
+    bool isBeingDisconnected() const { return disconnectWhenBytesWritten; }
     bool readyForDisconnecting() const { return disconnectWhenBytesWritten && writebuf.usedBytes() == 0; }
     // Do this before calling an action that makes this client ready for writing, so that the EPOLLOUT will handle it.
@@ -268,6 +268,11 @@ void MqttPacket::bufferToMqttPackets(CirBuf &amp;buf, std::vector&lt;MqttPacket&gt; &amp;packe
 void MqttPacket::handle()
 {
+    // It may be a stale client. This is especially important for when a session is picked up by another client. The old client
+    // may still have stale data in the buffer, causing action on the session otherwise.
+    if (sender->isBeingDisconnected())
+        return;
+
     if (packetType == PacketType::Reserved)
         throw ProtocolError("Packet type 0 specified, which is reserved and invalid.", ReasonCodes::MalformedPacket);