systemctl: delay pager/polkit agent opening as much as possible

In https://github.com/systemd/systemd/issues/3543, we would open the pager
before starting ssh, and the pipe fd was "leaked" into the ssh child as the
stderr fd. Previous commit fixes bus-socket to nullify stderr before launching
the child, but it seems reasonable to also delay starting the pager.
If we are going to croak when trying to open the transport, it seems better
to do this before starting the pager.

This commit would also fix #3543 on its own.

1 files changed, 50 insertions, 50 deletions

diff --git a/src/systemctl/systemctl.c b/src/systemctl/systemctl.c
index ecd875fa2d..f69c858bd6 100644
--- a/src/systemctl/systemctl.c
+++ b/src/systemctl/systemctl.c
@@ -735,12 +735,12 @@ static int list_units(int argc, char *argv[], void *userdata) {
         sd_bus *bus;
         int r;
 
-        pager_open(arg_no_pager, false);
-
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
                 return r;
 
+        pager_open(arg_no_pager, false);
+
         r = get_unit_list_recursive(bus, strv_skip(argv, 1), &unit_infos, &replies, &machines);
         if (r < 0)
                 return r;
@@ -947,12 +947,12 @@ static int list_sockets(int argc, char *argv[], void *userdata) {
         int r = 0, n;
         sd_bus *bus;
 
-        pager_open(arg_no_pager, false);
-
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
                 return r;
 
+        pager_open(arg_no_pager, false);
+
         n = get_unit_list_recursive(bus, strv_skip(argv, 1), &unit_infos, &replies, &machines);
         if (n < 0)
                 return n;
@@ -1254,12 +1254,12 @@ static int list_timers(int argc, char *argv[], void *userdata) {
         sd_bus *bus;
         int r = 0;
 
-        pager_open(arg_no_pager, false);
-
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
                 return r;
 
+        pager_open(arg_no_pager, false);
+
         n = get_unit_list_recursive(bus, strv_skip(argv, 1), &unit_infos, &replies, &machines);
         if (n < 0)
                 return n;
@@ -1425,8 +1425,6 @@ static int list_unit_files(int argc, char *argv[], void *userdata) {
         int r;
         bool fallback = false;
 
-        pager_open(arg_no_pager, false);
-
         if (install_client_side()) {
                 Hashmap *h;
                 UnitFileList *u;
@@ -1541,6 +1539,8 @@ static int list_unit_files(int argc, char *argv[], void *userdata) {
                         return bus_log_parse_error(r);
         }
 
+        pager_open(arg_no_pager, false);
+
         qsort_safe(units, c, sizeof(UnitFileList), compare_unit_file_list);
         output_unit_file_list(units, c);
 
@@ -1789,12 +1789,12 @@ static int list_dependencies(int argc, char *argv[], void *userdata) {
         } else
                 u = SPECIAL_DEFAULT_TARGET;
 
-        pager_open(arg_no_pager, false);
-
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
                 return r;
 
+        pager_open(arg_no_pager, false);
+
         puts(u);
 
         return list_dependencies_one(bus, u, 0, &units, 0);
@@ -2020,8 +2020,6 @@ static int list_machines(int argc, char *argv[], void *userdata) {
                 return -EPERM;
         }
 
-        pager_open(arg_no_pager, false);
-
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
                 return r;
@@ -2030,6 +2028,8 @@ static int list_machines(int argc, char *argv[], void *userdata) {
         if (r < 0)
                 return r;
 
+        pager_open(arg_no_pager, false);
+
         qsort_safe(machine_infos, r, sizeof(struct machine_info), compare_machine_info);
         output_machines_list(machine_infos, r);
         free_machines_list(machine_infos, r);
@@ -2233,8 +2233,6 @@ static int list_jobs(int argc, char *argv[], void *userdata) {
         int r;
         bool skipped = false;
 
-        pager_open(arg_no_pager, false);
-
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
                 return r;
@@ -2275,6 +2273,8 @@ static int list_jobs(int argc, char *argv[], void *userdata) {
         if (r < 0)
                 return bus_log_parse_error(r);
 
+        pager_open(arg_no_pager, false);
+
         output_jobs_list(jobs, c, skipped);
         return 0;
 }
@@ -2287,12 +2287,12 @@ static int cancel_job(int argc, char *argv[], void *userdata) {
         if (argc <= 1)
                 return trivial_method(argc, argv, userdata);
 
-        polkit_agent_open_if_enabled();
-
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
                 return r;
 
+        polkit_agent_open_if_enabled();
+
         STRV_FOREACH(name, strv_skip(argv, 1)) {
                 _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
                 uint32_t id;
@@ -2828,13 +2828,13 @@ static int start_unit(int argc, char *argv[], void *userdata) {
         char **name;
         int r = 0;
 
-        ask_password_agent_open_if_enabled();
-        polkit_agent_open_if_enabled();
-
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
                 return r;
 
+        ask_password_agent_open_if_enabled();
+        polkit_agent_open_if_enabled();
+
         if (arg_action == ACTION_SYSTEMCTL) {
                 enum action action;
 
@@ -2954,9 +2954,6 @@ static int logind_reboot(enum action a) {
         sd_bus *bus;
         int r;
 
-        polkit_agent_open_if_enabled();
-        (void) logind_set_wall_message();
-
         r = acquire_bus(BUS_FULL, &bus);
         if (r < 0)
                 return r;
@@ -2992,6 +2989,9 @@ static int logind_reboot(enum action a) {
                 return -EINVAL;
         }
 
+        polkit_agent_open_if_enabled();
+        (void) logind_set_wall_message();
+
         r = sd_bus_call_method(
                         bus,
                         "org.freedesktop.login1",
@@ -3338,12 +3338,12 @@ static int kill_unit(int argc, char *argv[], void *userdata) {
         sd_bus *bus;
         int r, q;
 
-        polkit_agent_open_if_enabled();
-
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
                 return r;
 
+        polkit_agent_open_if_enabled();
+
         if (!arg_kill_who)
                 arg_kill_who = "all";
 
@@ -4855,6 +4855,10 @@ static int show(int argc, char *argv[], void *userdata) {
                 return -EINVAL;
         }
 
+        r = acquire_bus(BUS_MANAGER, &bus);
+        if (r < 0)
+                return r;
+
         pager_open(arg_no_pager, false);
 
         if (show_status)
@@ -4863,10 +4867,6 @@ static int show(int argc, char *argv[], void *userdata) {
                  * be split up into many files. */
                 setrlimit_closest(RLIMIT_NOFILE, &RLIMIT_MAKE_CONST(16384));
 
-        r = acquire_bus(BUS_MANAGER, &bus);
-        if (r < 0)
-                return r;
-
         /* If no argument is specified inspect the manager itself */
         if (show_properties && argc <= 1)
                 return show_one(argv[0], bus, "/org/freedesktop/systemd1", NULL, show_properties, &new_line, &ellipsized);
@@ -5029,12 +5029,12 @@ static int set_property(int argc, char *argv[], void *userdata) {
         char **i;
         int r;
 
-        polkit_agent_open_if_enabled();
-
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
                 return r;
 
+        polkit_agent_open_if_enabled();
+
         r = sd_bus_message_new_method_call(
                         bus,
                         &m,
@@ -5081,12 +5081,12 @@ static int daemon_reload(int argc, char *argv[], void *userdata) {
         sd_bus *bus;
         int r;
 
-        polkit_agent_open_if_enabled();
-
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
                 return r;
 
+        polkit_agent_open_if_enabled();
+
         switch (arg_action) {
 
         case ACTION_RELOAD:
@@ -5141,12 +5141,12 @@ static int trivial_method(int argc, char *argv[], void *userdata) {
         sd_bus *bus;
         int r;
 
-        polkit_agent_open_if_enabled();
-
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
                 return r;
 
+        polkit_agent_open_if_enabled();
+
         method =
                 streq(argv[0], "clear-jobs")    ||
                 streq(argv[0], "cancel")        ? "ClearJobs" :
@@ -5184,12 +5184,12 @@ static int reset_failed(int argc, char *argv[], void *userdata) {
         if (argc <= 1)
                 return trivial_method(argc, argv, userdata);
 
-        polkit_agent_open_if_enabled();
-
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
                 return r;
 
+        polkit_agent_open_if_enabled();
+
         r = expand_names(bus, strv_skip(argv, 1), NULL, &names);
         if (r < 0)
                 return log_error_errno(r, "Failed to expand names: %m");
@@ -5223,12 +5223,12 @@ static int show_environment(int argc, char *argv[], void *userdata) {
         sd_bus *bus;
         int r;
 
-        pager_open(arg_no_pager, false);
-
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
                 return r;
 
+        pager_open(arg_no_pager, false);
+
         r = sd_bus_get_property(
                         bus,
                         "org.freedesktop.systemd1",
@@ -5332,12 +5332,12 @@ static int set_environment(int argc, char *argv[], void *userdata) {
         assert(argc > 1);
         assert(argv);
 
-        polkit_agent_open_if_enabled();
-
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
                 return r;
 
+        polkit_agent_open_if_enabled();
+
         method = streq(argv[0], "set-environment")
                 ? "SetEnvironment"
                 : "UnsetEnvironment";
@@ -5369,12 +5369,12 @@ static int import_environment(int argc, char *argv[], void *userdata) {
         sd_bus *bus;
         int r;
 
-        polkit_agent_open_if_enabled();
-
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
                 return r;
 
+        polkit_agent_open_if_enabled();
+
         r = sd_bus_message_new_method_call(
                         bus,
                         &m,
@@ -5666,12 +5666,12 @@ static int enable_unit(int argc, char *argv[], void *userdata) {
                 const char *method;
                 sd_bus *bus;
 
-                polkit_agent_open_if_enabled();
-
                 r = acquire_bus(BUS_MANAGER, &bus);
                 if (r < 0)
                         return r;
 
+                polkit_agent_open_if_enabled();
+
                 if (streq(verb, "enable")) {
                         method = "EnableUnitFiles";
                         expect_carries_install_info = true;
@@ -5832,12 +5832,12 @@ static int add_dependency(int argc, char *argv[], void *userdata) {
                 _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
                 sd_bus *bus;
 
-                polkit_agent_open_if_enabled();
-
                 r = acquire_bus(BUS_MANAGER, &bus);
                 if (r < 0)
                         return r;
 
+                polkit_agent_open_if_enabled();
+
                 r = sd_bus_message_new_method_call(
                                 bus,
                                 &m,
@@ -5894,12 +5894,12 @@ static int preset_all(int argc, char *argv[], void *userdata) {
                 _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
                 sd_bus *bus;
 
-                polkit_agent_open_if_enabled();
-
                 r = acquire_bus(BUS_MANAGER, &bus);
                 if (r < 0)
                         return r;
 
+                polkit_agent_open_if_enabled();
+
                 r = sd_bus_call_method(
                                 bus,
                                 "org.freedesktop.systemd1",
@@ -7720,8 +7720,6 @@ static int logind_schedule_shutdown(void) {
         sd_bus *bus;
         int r;
 
-        (void) logind_set_wall_message();
-
         r = acquire_bus(BUS_FULL, &bus);
         if (r < 0)
                 return r;
@@ -7748,6 +7746,8 @@ static int logind_schedule_shutdown(void) {
         if (arg_dry)
                 action = strjoina("dry-", action);
 
+        (void) logind_set_wall_message();
+
         r = sd_bus_call_method(
                         bus,
                         "org.freedesktop.login1",