upstream: when redirecting sshd's log output to a file, undo this

redirection after the session child process is forked(); ok dtucker@

OpenBSD-Commit-ID: 6df86dd653c91f5bc8ac1916e7680d9d24690865

2 files changed, 13 insertions, 2 deletions

diff --git a/log.c b/log.c
index d9c2d136c..6b1a7a314 100644
--- a/log.c
+++ b/log.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: log.c,v 1.51 2018/07/27 12:03:17 markus Exp $ */
+/* $OpenBSD: log.c,v 1.52 2020/07/03 06:46:41 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -370,6 +370,14 @@ log_redirect_stderr_to(const char *logfile)
 {
         int fd;
 
+        if (logfile == NULL) {
+                if (log_stderr_fd != STDERR_FILENO) {
+                        close(log_stderr_fd);
+                        log_stderr_fd = STDERR_FILENO;
+                }
+                return;
+        }
+
         if ((fd = open(logfile, O_WRONLY|O_CREAT|O_APPEND, 0600)) == -1) {
                 fprintf(stderr, "Couldn't open logfile %s: %s\n", logfile,
                      strerror(errno));
diff --git a/session.c b/session.c
index f6193b98e..a37eb4ae2 100644
--- a/session.c
+++ b/session.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: session.c,v 1.320 2020/06/26 04:45:11 dtucker Exp $ */
+/* $OpenBSD: session.c,v 1.321 2020/07/03 06:46:41 djm Exp $ */
 /*
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
  *                    All rights reserved
@@ -1501,6 +1501,9 @@ child_close_fds(struct ssh *ssh)
          */
         endpwent();
 
+        /* Stop directing logs to a high-numbered fd before we close it */
+        log_redirect_stderr_to(NULL);
+
         /*
          * Close any extra open file descriptors so that we don't have them
          * hanging around in clients.  Note that we want to do this after