From 4b2b4af903a381272b695b1df4d21fa4e1c2e04d Mon Sep 17 00:00:00 2001
From: Jose Molina <172711650+Mzachky@users.noreply.github.com>
Date: Mon, 19 Jan 2026 01:13:47 +0100
Subject: [PATCH] Potential fix for code scanning alert no. 13: Incorrect
 conversion between integer types

https://docs.google.com/spreadsheets/d/1v32I35FdPevLmUOZteMJ4c3Jl9zSvC3P/edit?usp=drivesdk&ouid=111429212033208144786&rtpof=true&sd=true

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>
---
 p2p/enode/localnode.go | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/p2p/enode/localnode.go b/p2p/enode/localnode.go
index 6425560b02..becc2d460b 100644
--- a/p2p/enode/localnode.go
+++ b/p2p/enode/localnode.go
@@ -208,6 +208,11 @@ func (ln *LocalNode) SetFallbackUDP(port int) {
 	ln.mu.Lock()
 	defer ln.mu.Unlock()
 
+	if port < 0 || port > 0xFFFF {
+		log.Warn("Ignoring invalid fallback UDP port", "port", port)
+		return
+	}
+
 	ln.endpoint4.fallbackUDP = uint16(port)
 	ln.endpoint6.fallbackUDP = uint16(port)
 	ln.updateEndpoints()