packages/openssh
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
openssh/backport-upstream-Fix-proxy-multiplexing-O-proxy-bug.patch
bitianyuan d9d3952e6d backport some upstream patches 
(cherry picked from commit 2ad55f43cb143356916313e5b648c32857f76555)
2024-11-18 14:28:58 +08:00

158 lines
5.9 KiB
Diff
Raw Permalink Blame History

From 29fb6f6d46b67770084b4f12bcf8a01bd535041b Mon Sep 17 00:00:00 2001
From: "djm@openbsd.org" <djm@openbsd.org>
Date: Thu, 25 Jul 2024 22:40:08 +0000
Subject: [PATCH] upstream: Fix proxy multiplexing (-O proxy) bug
If a mux started with ControlPersist then later has a forwarding added using
mux proxy connection and the forwarding was used, then when the mux proxy
session terminates, the mux master process will send a channel close to the
server with a bad channel ID and crash the connection.
This was caused by my stupidly reusing c->remote_id for mux channel
associations when I should have just added another member to struct channel.
OpenBSD-Commit-ID: c9f474e0124e3fe456c5e43749b97d75e65b82b2
Reference:https://anongit.mindrot.org/openssh.git/commit/29fb6f6d46b67770084b4f12bcf8a01bd535041b
Conflict:NA
---
channels.c | 6 ++++--
channels.h | 2 ++
mux.c | 26 +++++++++++++-------------
nchan.c | 4 +++-
4 files changed, 22 insertions(+), 16 deletions(-)
diff --git a/channels.c b/channels.c
index 2c0aa65..02f5441 100644
--- a/channels.c
+++ b/channels.c
@@ -964,14 +964,16 @@ channel_format_status(const Channel *c)
{
char *ret = NULL;
- xasprintf(&ret, "t%d [%s] %s%u i%u/%zu o%u/%zu e[%s]/%zu "
- "fd %d/%d/%d sock %d cc %d io 0x%02x/0x%02x",
+ xasprintf(&ret, "t%d [%s] %s%u %s%u i%u/%zu o%u/%zu e[%s]/%zu "
+ "fd %d/%d/%d sock %d cc %d %s%u io 0x%02x/0x%02x",
c->type, c->xctype != NULL ? c->xctype : c->ctype,
c->have_remote_id ? "r" : "nr", c->remote_id,
+ c->mux_ctx != NULL ? "m" : "nm", c->mux_downstream_id,
c->istate, sshbuf_len(c->input),
c->ostate, sshbuf_len(c->output),
channel_format_extended_usage(c), sshbuf_len(c->extended),
c->rfd, c->wfd, c->efd, c->sock, c->ctl_chan,
+ c->have_ctl_child_id ? "c" : "nc", c->ctl_child_id,
c->io_want, c->io_ready);
return ret;
}
diff --git a/channels.h b/channels.h
index 7e59914..f3dd87d 100644
--- a/channels.h
+++ b/channels.h
@@ -140,6 +140,8 @@ struct Channel {
u_int io_ready; /* bitmask of SSH_CHAN_IO_* */
int pfds[4]; /* pollfd entries for rfd/wfd/efd/sock */
int ctl_chan; /* control channel (multiplexed connections) */
+ uint32_t ctl_child_id; /* child session for mux controllers */
+ int have_ctl_child_id; /* non-zero if ctl_child_id is valid */
int isatty; /* rfd is a tty */
#ifdef _AIX
int wfd_isatty; /* wfd is a tty */
diff --git a/mux.c b/mux.c
index b3ffde9..f391892 100644
--- a/mux.c
+++ b/mux.c
@@ -199,8 +199,8 @@ mux_master_session_cleanup_cb(struct ssh *ssh, int cid, int force, void *unused)
fatal_f("channel %d missing control channel %d",
c->self, c->ctl_chan);
c->ctl_chan = -1;
- cc->remote_id = 0;
- cc->have_remote_id = 0;
+ cc->ctl_child_id = 0;
+ cc->have_ctl_child_id = 0;
chan_rcvd_oclose(ssh, cc);
}
channel_cancel_cleanup(ssh, c->self);
@@ -215,12 +215,12 @@ mux_master_control_cleanup_cb(struct ssh *ssh, int cid, int force, void *unused)
debug3_f("entering for channel %d", cid);
if (c == NULL)
fatal_f("channel_by_id(%i) == NULL", cid);
- if (c->have_remote_id) {
- if ((sc = channel_by_id(ssh, c->remote_id)) == NULL)
+ if (c->have_ctl_child_id) {
+ if ((sc = channel_by_id(ssh, c->ctl_child_id)) == NULL)
fatal_f("channel %d missing session channel %u",
- c->self, c->remote_id);
- c->remote_id = 0;
- c->have_remote_id = 0;
+ c->self, c->ctl_child_id);
+ c->ctl_child_id = 0;
+ c->have_ctl_child_id = 0;
sc->ctl_chan = -1;
if (sc->type != SSH_CHANNEL_OPEN &&
sc->type != SSH_CHANNEL_OPENING) {
@@ -416,7 +416,7 @@ mux_master_process_new_session(struct ssh *ssh, u_int rid,
new_fd[0], new_fd[1], new_fd[2]);
/* XXX support multiple child sessions in future */
- if (c->have_remote_id) {
+ if (c->have_ctl_child_id) {
debug2_f("session already open");
reply_error(reply, MUX_S_FAILURE, rid,
"Multiple sessions not supported");
@@ -461,8 +461,8 @@ mux_master_process_new_session(struct ssh *ssh, u_int rid,
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 */
- c->have_remote_id = 1;
+ c->ctl_child_id = nc->self; /* link control -> session channel */
+ c->have_ctl_child_id = 1;
if (cctx->want_tty && escape_char != 0xffffffff) {
channel_register_filter(ssh, nc->self,
@@ -992,7 +992,7 @@ mux_master_process_stdio_fwd(struct ssh *ssh, u_int rid,
debug3_f("got fds stdin %d, stdout %d", new_fd[0], new_fd[1]);
/* XXX support multiple child sessions in future */
- if (c->have_remote_id) {
+ if (c->have_ctl_child_id) {
debug2_f("session already open");
reply_error(reply, MUX_S_FAILURE, rid,
"Multiple sessions not supported");
@@ -1019,8 +1019,8 @@ mux_master_process_stdio_fwd(struct ssh *ssh, u_int rid,
free(chost);
nc->ctl_chan = c->self; /* link session -> control channel */
- c->remote_id = nc->self; /* link control -> session channel */
- c->have_remote_id = 1;
+ c->ctl_child_id = nc->self; /* link control -> session channel */
+ c->have_ctl_child_id = 1;
debug2_f("channel_new: %d control %d", nc->self, nc->ctl_chan);
diff --git a/nchan.c b/nchan.c
index d33426f..715feeb 100644
--- a/nchan.c
+++ b/nchan.c
@@ -208,7 +208,7 @@ chan_send_close2(struct ssh *ssh, Channel *c)
{
int r;
- debug2("channel %d: send close", c->self);
+ debug2("channel %d: send close2", c->self);
if (c->ostate != CHAN_OUTPUT_CLOSED ||
c->istate != CHAN_INPUT_CLOSED) {
error("channel %d: cannot send close for istate/ostate %d/%d",
@@ -218,6 +218,8 @@ chan_send_close2(struct ssh *ssh, Channel *c)
} else {
if (!c->have_remote_id)
fatal_f("channel %d: no remote_id", c->self);
+ debug2("channel %d: send close for remote id %u", c->self,
+ c->remote_id);
if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_CLOSE)) != 0 ||
(r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
(r = sshpkt_send(ssh)) != 0)
--
2.43.0
Reference in New Issue View Git Blame Copy Permalink