diff options
author | Damien Miller <djm@cvs.openbsd.org> | 2017-10-25 00:21:38 +0000 |
---|---|---|
committer | Damien Miller <djm@cvs.openbsd.org> | 2017-10-25 00:21:38 +0000 |
commit | d466238eb7b2f846af6e213fbb77b41c62db3315 (patch) | |
tree | 479e753eb240b62fa0217658fb4793efa9308c4f /usr.bin/ssh | |
parent | 6073e3054f7de5795bc6172c21f93e6f5c9e42db (diff) |
transfer ownership of stdout to the session channel by dup2'ing
/dev/null to fd 1. This allows propagation of remote stdout close to
the local side; reported by David Newall, ok markus@
Diffstat (limited to 'usr.bin/ssh')
-rw-r--r-- | usr.bin/ssh/ssh.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/usr.bin/ssh/ssh.c b/usr.bin/ssh/ssh.c index 9053a8f056d..659226134e7 100644 --- a/usr.bin/ssh/ssh.c +++ b/usr.bin/ssh/ssh.c @@ -1,4 +1,4 @@ -/* $OpenBSD: ssh.c,v 1.466 2017/10/23 05:08:00 djm Exp $ */ +/* $OpenBSD: ssh.c,v 1.467 2017/10/25 00:21:37 djm Exp $ */ /* * Author: Tatu Ylonen <ylo@cs.hut.fi> * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland @@ -1767,7 +1767,7 @@ ssh_session2_open(struct ssh *ssh) static int ssh_session2(struct ssh *ssh, struct passwd *pw) { - int id = -1; + int devnull, id = -1; char *cp, *tun_fwd_ifname = NULL; /* XXX should be pre-session */ @@ -1851,6 +1851,20 @@ ssh_session2(struct ssh *ssh, struct passwd *pw) ssh_local_cmd(options.local_command); /* + * stdout is now owned by the session channel; clobber it here + * so future channel closes are propagated to the local fd. + * NB. this can only happen after LocalCommand has completed, + * as it may want to write to stdout. + */ + if ((devnull = open(_PATH_DEVNULL, O_WRONLY)) == -1) + error("%s: open %s: %s", __func__, + _PATH_DEVNULL, strerror(errno)); + if (dup2(devnull, STDOUT_FILENO) < 0) + fatal("%s: dup2() stdout failed", __func__); + if (devnull > STDERR_FILENO) + close(devnull); + + /* * If requested and we are not interested in replies to remote * forwarding requests, then let ssh continue in the background. */ |