From 95802bf0349e70d56eb00f7183a5dc4ff4655f09 Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Thu, 16 Jun 2016 15:29:16 +0200
Subject: [PATCH] systemctl: make sure we terminate the bus connection first,
 and then close the pager (#3550)

If "systemctl -H" is used, let's make sure we first terminate the bus
connection, and only then close the pager. If done in this order ssh will get
an EOF on stdin (as we speak D-Bus through ssh's stdin/stdout), and then
terminate. This makes sure the standard error we were invoked on is released by
ssh, and only that makes sure we don't deadlock on the pager which waits for
all clients closing its input pipe.

(Similar fixes for the various other xyzctl tools that support both pagers and
-H)

Fixes: #3543
(cherry picked from commit cf647b69baee4c478d3909c327e3d917e1563f44)
Resolves: rhbug#1341179
---
 src/libsystemd/sd-bus/busctl.c | 3 ++-
 src/locale/localectl.c         | 3 ++-
 src/login/loginctl.c           | 4 +++-
 src/machine/machinectl.c       | 3 ++-
 src/systemctl/systemctl.c      | 4 ++--
 src/timedate/timedatectl.c     | 3 ++-
 6 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/src/libsystemd/sd-bus/busctl.c b/src/libsystemd/sd-bus/busctl.c
index 35fabf038c..c806d6fe96 100644
--- a/src/libsystemd/sd-bus/busctl.c
+++ b/src/libsystemd/sd-bus/busctl.c
@@ -1974,7 +1974,7 @@ static int busctl_main(sd_bus *bus, int argc, char *argv[]) {
 }
 
 int main(int argc, char *argv[]) {
-        _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
+        sd_bus *bus = NULL;
         int r;
 
         log_parse_environment();
@@ -2065,6 +2065,7 @@ int main(int argc, char *argv[]) {
         r = busctl_main(bus, argc, argv);
 
 finish:
+        sd_bus_flush_close_unref(bus);
         pager_close();
 
         strv_free(arg_matches);
diff --git a/src/locale/localectl.c b/src/locale/localectl.c
index 365c79aa51..45404f1fa7 100644
--- a/src/locale/localectl.c
+++ b/src/locale/localectl.c
@@ -664,7 +664,7 @@ static int localectl_main(sd_bus *bus, int argc, char *argv[]) {
 }
 
 int main(int argc, char*argv[]) {
-        _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
+        sd_bus *bus = NULL;
         int r;
 
         setlocale(LC_ALL, "");
@@ -684,6 +684,7 @@ int main(int argc, char*argv[]) {
         r = localectl_main(bus, argc, argv);
 
 finish:
+        sd_bus_flush_close_unref(bus);
         pager_close();
 
         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
diff --git a/src/login/loginctl.c b/src/login/loginctl.c
index 6ad3d089bd..601d18063e 100644
--- a/src/login/loginctl.c
+++ b/src/login/loginctl.c
@@ -1532,7 +1532,7 @@ static int loginctl_main(int argc, char *argv[], sd_bus *bus) {
 }
 
 int main(int argc, char *argv[]) {
-        _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
+        sd_bus *bus = NULL;
         int r;
 
         setlocale(LC_ALL, "");
@@ -1554,6 +1554,8 @@ int main(int argc, char *argv[]) {
         r = loginctl_main(argc, argv, bus);
 
 finish:
+        sd_bus_flush_close_unref(bus);
+
         pager_close();
         polkit_agent_close();
 
diff --git a/src/machine/machinectl.c b/src/machine/machinectl.c
index 4853139321..479822880c 100644
--- a/src/machine/machinectl.c
+++ b/src/machine/machinectl.c
@@ -2646,7 +2646,7 @@ static int machinectl_main(int argc, char *argv[], sd_bus *bus) {
 }
 
 int main(int argc, char*argv[]) {
-        _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
+        sd_bus *bus = NULL;
         int r;
 
         setlocale(LC_ALL, "");
@@ -2668,6 +2668,7 @@ int main(int argc, char*argv[]) {
         r = machinectl_main(argc, argv, bus);
 
 finish:
+        sd_bus_flush_close_unref(bus);
         pager_close();
         polkit_agent_close();
 
diff --git a/src/systemctl/systemctl.c b/src/systemctl/systemctl.c
index b4581fe542..0996920241 100644
--- a/src/systemctl/systemctl.c
+++ b/src/systemctl/systemctl.c
@@ -7684,6 +7684,8 @@ int main(int argc, char*argv[]) {
         }
 
 finish:
+        release_busses();
+
         pager_close();
         ask_password_agent_close();
         polkit_agent_close();
@@ -7695,8 +7697,6 @@ finish:
         strv_free(arg_wall);
         free(arg_root);
 
-        release_busses();
-
         /* Note that we return r here, not EXIT_SUCCESS, so that we can implement the LSB-like return codes */
 
         return r < 0 ? EXIT_FAILURE : r;
diff --git a/src/timedate/timedatectl.c b/src/timedate/timedatectl.c
index 097963b41b..7e88fd15c8 100644
--- a/src/timedate/timedatectl.c
+++ b/src/timedate/timedatectl.c
@@ -488,7 +488,7 @@ static int timedatectl_main(sd_bus *bus, int argc, char *argv[]) {
 }
 
 int main(int argc, char *argv[]) {
-        _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
+        sd_bus *bus = NULL;
         int r;
 
         setlocale(LC_ALL, "");
@@ -508,6 +508,7 @@ int main(int argc, char *argv[]) {
         r = timedatectl_main(bus, argc, argv);
 
 finish:
+        sd_bus_flush_close_unref(bus);
         pager_close();
 
         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;