diff options
| author | djm@openbsd.org <djm@openbsd.org> | 2021-05-19 01:24:05 +0000 |
|---|---|---|
| committer | Damien Miller <djm@mindrot.org> | 2021-05-19 11:52:14 +1000 |
| commit | 7be4ac813662f68e89f23c50de058a49aa32f7e4 (patch) | |
| tree | 7040d1e4601e2a0545e20614e96d8d818eccbf35 /mux.c | |
| parent | c4902e1a653c67fea850ec99c7537f358904c0af (diff) | |
| download | openssh-git-7be4ac813662f68e89f23c50de058a49aa32f7e4.tar.gz | |
upstream: restore blocking status on stdio fds before close
ssh(1) needs to set file descriptors to non-blocking mode to operate
but it was not restoring the original state on exit. This could cause
problems with fds shared with other programs via the shell, e.g.
> $ cat > test.sh << _EOF
> #!/bin/sh
> {
> ssh -Fnone -oLogLevel=verbose ::1 hostname
> cat /usr/share/dict/words
> } | sleep 10
> _EOF
> $ ./test.sh
> Authenticated to ::1 ([::1]:22).
> Transferred: sent 2352, received 2928 bytes, in 0.1 seconds
> Bytes per second: sent 44338.9, received 55197.4
> cat: stdout: Resource temporarily unavailable
This restores the blocking status for fds 0,1,2 (stdio) before ssh(1)
abandons/closes them.
This was reported as bz3280 and GHPR246; ok dtucker@
OpenBSD-Commit-ID: 8cc67346f05aa85a598bddf2383fcfcc3aae61ce
Diffstat (limited to 'mux.c')
| -rw-r--r-- | mux.c | 21 |
1 files changed, 4 insertions, 17 deletions
@@ -1,4 +1,4 @@ -/* $OpenBSD: mux.c,v 1.87 2021/04/03 06:18:40 djm Exp $ */ +/* $OpenBSD: mux.c,v 1.88 2021/05/19 01:24:05 djm Exp $ */ /* * Copyright (c) 2002-2008 Damien Miller <djm@openbsd.org> * @@ -452,14 +452,6 @@ mux_master_process_new_session(struct ssh *ssh, u_int rid, if (cctx->want_tty && tcgetattr(new_fd[0], &cctx->tio) == -1) error_f("tcgetattr: %s", strerror(errno)); - /* enable nonblocking unless tty */ - if (!isatty(new_fd[0])) - set_nonblock(new_fd[0]); - if (!isatty(new_fd[1])) - set_nonblock(new_fd[1]); - if (!isatty(new_fd[2])) - set_nonblock(new_fd[2]); - window = CHAN_SES_WINDOW_DEFAULT; packetmax = CHAN_SES_PACKET_DEFAULT; if (cctx->want_tty) { @@ -469,7 +461,7 @@ mux_master_process_new_session(struct ssh *ssh, u_int rid, nc = channel_new(ssh, "session", SSH_CHANNEL_OPENING, new_fd[0], new_fd[1], new_fd[2], window, packetmax, - CHAN_EXTENDED_WRITE, "client-session", /*nonblock*/0); + CHAN_EXTENDED_WRITE, "client-session", CHANNEL_NONBLOCK_STDIO); nc->ctl_chan = c->self; /* link session -> control channel */ c->remote_id = nc->self; /* link control -> session channel */ @@ -1025,13 +1017,8 @@ mux_master_process_stdio_fwd(struct ssh *ssh, u_int rid, } } - /* enable nonblocking unless tty */ - if (!isatty(new_fd[0])) - set_nonblock(new_fd[0]); - if (!isatty(new_fd[1])) - set_nonblock(new_fd[1]); - - nc = channel_connect_stdio_fwd(ssh, chost, cport, new_fd[0], new_fd[1]); + nc = channel_connect_stdio_fwd(ssh, chost, cport, new_fd[0], new_fd[1], + CHANNEL_NONBLOCK_STDIO); free(chost); nc->ctl_chan = c->self; /* link session -> control channel */ |