diff --git a/other/bootstrap_daemon/tox-bootstrapd.c b/other/bootstrap_daemon/tox-bootstrapd.c
index 0848cd177..a0f93bb33 100644
--- a/other/bootstrap_daemon/tox-bootstrapd.c
+++ b/other/bootstrap_daemon/tox-bootstrapd.c
@@ -210,7 +210,9 @@ void parse_tcp_relay_ports_config(config_t *cfg, uint16_t **tcp_relay_ports, int
     }
 
     // the loop above skips invalid ports, so we adjust the allocated memory size
-    *tcp_relay_ports = realloc(*tcp_relay_ports, (*tcp_relay_port_count) * sizeof(uint16_t));
+    if ((*tcp_relay_port_count) * sizeof(uint16_t) > 0) {
+        *tcp_relay_ports = realloc(*tcp_relay_ports, (*tcp_relay_port_count) * sizeof(uint16_t));
+    }
 }
 
 // Gets general config options