upstream commit

close ControlPersist background process stderr when not
 in debug mode or when logging to a file or syslog. bz#1988 ok dtucker

Upstream-ID: 4fb726f0fdcb155ad419913cea10dc4afd409d24

1 files changed, 5 insertions, 3 deletions

diff --git a/ssh.c b/ssh.c
index a999d5079..a881ba14c 100644
--- a/ssh.c
+++ b/ssh.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh.c,v 1.437 2016/03/07 19:02:43 djm Exp $ */
+/* $OpenBSD: ssh.c,v 1.438 2016/04/29 08:07:53 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -1395,7 +1395,7 @@ static void
 control_persist_detach(void)
 {
         pid_t pid;
-        int devnull;
+        int devnull, keep_stderr;
 
         debug("%s: backgrounding master process", __func__);
 
@@ -1426,8 +1426,10 @@ control_persist_detach(void)
                 error("%s: open(\"/dev/null\"): %s", __func__,
                     strerror(errno));
         } else {
+                keep_stderr = log_is_on_stderr() && debug_flag;
                 if (dup2(devnull, STDIN_FILENO) == -1 ||
-                    dup2(devnull, STDOUT_FILENO) == -1)
+                    dup2(devnull, STDOUT_FILENO) == -1 ||
+                    (!keep_stderr && dup2(devnull, STDERR_FILENO) == -1))
                         error("%s: dup2: %s", __func__, strerror(errno));
                 if (devnull > STDERR_FILENO)
                         close(devnull);