upstream commit

The file descriptors for socket, stdin, stdout and stderr
aren't necessarily distinct, so check if they are the same to avoid closing
the same fd several times.

ok djm

OpenBSD-Commit-ID: 60d71fd22e9a32f5639d4ba6e25a2f417fc36ac1

1 files changed, 9 insertions, 4 deletions

diff --git a/channels.c b/channels.c
index 1c381e0e2..bdee1f386 100644
--- a/channels.c
+++ b/channels.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: channels.c,v 1.378 2018/01/23 05:27:21 djm Exp $ */
+/* $OpenBSD: channels.c,v 1.379 2018/02/05 05:36:49 tb Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -436,10 +436,15 @@ channel_close_fd(struct ssh *ssh, int *fdp)
 static void
 channel_close_fds(struct ssh *ssh, Channel *c)
 {
+        int sock = c->sock, rfd = c->rfd, wfd = c->wfd, efd = c->efd;
+
         channel_close_fd(ssh, &c->sock);
-        channel_close_fd(ssh, &c->rfd);
-        channel_close_fd(ssh, &c->wfd);
-        channel_close_fd(ssh, &c->efd);
+        if (rfd != sock)
+                channel_close_fd(ssh, &c->rfd);
+        if (wfd != sock && wfd != rfd)
+                channel_close_fd(ssh, &c->wfd);
+        if (efd != sock && efd != rfd && efd != wfd)
+                channel_close_fd(ssh, &c->efd);
 }
 
 static void