bindlocal: detect and avoid IP version mismatches in bind()

Reported-by: Alex Grebenschikov Fixes #3993 Closes #4002
curl · Jun 10, 2019 · 1667d55 · 1667d55
1 parent 094b5f3
commit 1667d55
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/lib/connect.c b/lib/connect.c
@@ -368,6 +368,11 @@ static CURLcode bindlocal(struct connectdata *conn,
         infof(data, "Name '%s' family %i resolved to '%s' family %i\n",
               dev, af, myhost, h->addr->ai_family);
         Curl_resolv_unlock(data, h);
+        if(af != h->addr->ai_family) {
+          /* bad IP version combo, signal the caller to try another address
+             family if available */
+          return CURLE_UNSUPPORTED_PROTOCOL;
+        }
         done = 1;
       }
       else {