setopt: disable CURLOPT_HAPROXY_CLIENT_IP on NULL

As documented.

Reported-by: Stanislav Fort (Aisle Research)
Closes #19434

diff --git a/lib/setopt.c b/lib/setopt.c
index 90a1cf24a8d14f7a7b63204f076019fb675ee2e0..67b5371e87ddacd6dba33c467b8287f866467c6b 100644 (file)
--- a/lib/setopt.c
+++ b/lib/setopt.c
@@ -2169,8 +2169,9 @@ static CURLcode setopt_cptr(struct Curl_easy *data, CURLoption option,
      * Set the client IP to send through HAProxy PROXY protocol
      */
     result = Curl_setstropt(&s->str[STRING_HAPROXY_CLIENT_IP], ptr);
-    /* enable the HAProxy protocol */
-    s->haproxyprotocol = TRUE;
+
+    /* enable the HAProxy protocol if an IP is provided */
+    s->haproxyprotocol = !!s->str[STRING_HAPROXY_CLIENT_IP];
     break;
 
 #endif