Fix from review

embhorn · embhorn · commit fa72abdc541e · 2026-04-22T07:51:31.000-05:00
diff --git a/src/mqtt_client.c b/src/mqtt_client.c
@@ -2764,7 +2764,11 @@ int MqttClient_Auth(MqttClient *client, MqttAuth* auth)
             wm_SemUnlock(&client->lockClient);
         }
         if (rc != 0) {
+            /* Save write.len before MqttWriteStop zeroes client->write */
+            int xfer = client->write.len;
             MqttWriteStop(client, &auth->stat);
+            /* Clear tx_buf to remove SASL auth data before returning */
+            CLIENT_FORCE_ZERO(client->tx_buf, xfer);
             return rc; /* Error locking client */
         }
     #endif

Original file line number	Diff line number	Diff line change
`@@ -2764,7 +2764,11 @@ int MqttClient_Auth(MqttClient client, MqttAuth auth)`
`2764`	`2764`	`wm_SemUnlock(&client->lockClient);`
`2765`	`2765`	`}`
`2766`	`2766`	`if (rc != 0) {`
	`2767`	`+ /* Save write.len before MqttWriteStop zeroes client->write */`
	`2768`	`+ int xfer = client->write.len;`
`2767`	`2769`	`MqttWriteStop(client, &auth->stat);`
	`2770`	`+ /* Clear tx_buf to remove SASL auth data before returning */`
	`2771`	`+ CLIENT_FORCE_ZERO(client->tx_buf, xfer);`
`2768`	`2772`	`return rc; /* Error locking client */`
`2769`	`2773`	`}`
`2770`	`2774`	`#endif`