From 6e96ff3204d40dbf7b251c2ccd38f2782284189b Mon Sep 17 00:00:00 2001
From: Romeo Rosete <roseteromeo56@gmail.com>
Date: Tue, 20 May 2025 10:14:03 -0400
Subject: [PATCH] Potential fix for code scanning alert no. 9: Incorrect
 conversion between integer types

Romeo Rosete

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>
---
 cmd/devp2p/discv4cmd.go | 2 +-
 p2p/enode/localnode.go  | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/cmd/devp2p/discv4cmd.go b/cmd/devp2p/discv4cmd.go
index 84c7ef0c44..4896e52902 100644
--- a/cmd/devp2p/discv4cmd.go
+++ b/cmd/devp2p/discv4cmd.go
@@ -336,7 +336,7 @@ func parseExtAddr(spec string) (ip net.IP, port int, ok bool) {
 		return nil, 0, false
 	}
 	port, err = strconv.Atoi(portstr)
-	if err != nil {
+	if err != nil || port < 0 || port > 65535 {
 		return nil, 0, false
 	}
 	return ip, port, true
diff --git a/p2p/enode/localnode.go b/p2p/enode/localnode.go
index 6e79c9cbdc..46c04e5ac4 100644
--- a/p2p/enode/localnode.go
+++ b/p2p/enode/localnode.go
@@ -205,6 +205,10 @@ func (ln *LocalNode) SetFallbackIP(ip net.IP) {
 // SetFallbackUDP sets the last-resort UDP-on-IPv4 port. This port is used
 // if no endpoint prediction can be made.
 func (ln *LocalNode) SetFallbackUDP(port int) {
+	if port < 0 || port > 65535 {
+		log.Error("Invalid port value, must be in range 0-65535", "port", port)
+		return
+	}
 	ln.mu.Lock()
 	defer ln.mu.Unlock()