From f1ed50a51707847825eb988cfc739f79b5ceadc9 Mon Sep 17 00:00:00 2001
From: Daniel Stenberg <daniel@haxx.se>
Date: Mon, 6 Oct 2025 17:23:18 +0200
Subject: [PATCH] tftp: don't pin or check address if recvfrom returns error

Follow-up to c4f9977c66bbb05a837a7eb0300
Reported-by: Joshua Rogers
Closes #18892
---
 lib/tftp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/tftp.c b/lib/tftp.c
index b81fd3ee14..baebe466a1 100644
--- a/lib/tftp.c
+++ b/lib/tftp.c
@@ -1105,7 +1105,7 @@ static CURLcode tftp_receive_packet(struct Curl_easy *data,
                                 0,
                                 (struct sockaddr *)&remote_addr,
                                 &fromlen);
-  if(fromlen) {
+  if((state->rbytes >= 0) && fromlen) {
     if(state->remote_pinned) {
       /* pinned, verify that it comes from the same address */
       if((state->remote_addrlen != fromlen) ||