upstream: Detect and prevent simple configuration loops when using

ProxyJump. bz#3057, ok djm@

OpenBSD-Commit-ID: 077d21c564c886c98309d871ed6f8ef267b9f037

1 files changed, 9 insertions, 1 deletions

diff --git a/ssh.c b/ssh.c
index 15aee569e..a983a108b 100644
--- a/ssh.c
+++ b/ssh.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh.c,v 1.519 2020/02/07 03:54:44 dtucker Exp $ */
+/* $OpenBSD: ssh.c,v 1.520 2020/02/18 08:49:49 dtucker Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -1208,6 +1208,14 @@ main(int ac, char **av)
         if (options.jump_host != NULL) {
                 char port_s[8];
                 const char *sshbin = argv0;
+                int port = options.port, jumpport = options.jump_port;
+
+                if (port <= 0)
+                        port = default_ssh_port();
+                if (jumpport <= 0)
+                        jumpport = default_ssh_port();
+                if (strcmp(options.jump_host, host) == 0 && port == jumpport)
+                        fatal("jumphost loop via %s", options.jump_host);
 
                 /*
                  * Try to use SSH indicated by argv[0], but fall back to