From c2993daaf179cfeb6ab1e0df6e644117a76d3db3 Mon Sep 17 00:00:00 2001
From: djm <djm@openbsd.org>
Date: Tue, 30 Apr 2024 05:53:03 +0000
Subject: [PATCH] stricter validation of messaging socket fd number; disallow
 usage of stderr. Based on GHPR492 by RealHurrison

---
 usr.bin/ssh/ssh-keysign.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/usr.bin/ssh/ssh-keysign.c b/usr.bin/ssh/ssh-keysign.c
index 97a117ed951..434c7503f7c 100644
--- a/usr.bin/ssh/ssh-keysign.c
+++ b/usr.bin/ssh/ssh-keysign.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-keysign.c,v 1.73 2024/01/11 01:51:16 djm Exp $ */
+/* $OpenBSD: ssh-keysign.c,v 1.74 2024/04/30 05:53:03 djm Exp $ */
 /*
  * Copyright (c) 2002 Markus Friedl.  All rights reserved.
  *
@@ -265,7 +265,7 @@ main(int argc, char **argv)
 		    __progname, rver, version);
 	if ((r = sshbuf_get_u32(b, (u_int *)&fd)) != 0)
 		fatal_r(r, "%s: buffer error", __progname);
-	if (fd < 0 || fd == STDIN_FILENO || fd == STDOUT_FILENO)
+	if (fd <= STDERR_FILENO)
 		fatal("%s: bad fd = %d", __progname, fd);
 	if ((host = get_local_name(fd)) == NULL)
 		fatal("%s: cannot get local name for fd", __progname);
-- 
2.20.1