From 0d0ecaab000cf2768a3edf1e73119bf2fce952b0 Mon Sep 17 00:00:00 2001

From: Daan De Meyer <daan.j.demeyer@gmail.com>

Date: Wed, 9 Oct 2024 14:49:07 +0200

Subject: [PATCH 1/6] mkosi: Fix up ownership of testuser home directory on

 first boot

When building unprivileged, the testuser home directory ends up

owned by root:root because mkosi can't chown directories to other

owners when running unprivileged. So let's fix up the testuser

ownership on first boot with tmpfiles instead.

---

 mkosi.extra/usr/lib/tmpfiles.d/testuser.conf | 3 +++

 1 file changed, 3 insertions(+)

 create mode 100644 mkosi.extra/usr/lib/tmpfiles.d/testuser.conf

diff --git a/mkosi.extra/usr/lib/tmpfiles.d/testuser.conf b/mkosi.extra/usr/lib/tmpfiles.d/testuser.conf

new file mode 100644

index 0000000000000..7113177f4deba

--- /dev/null

+++ b/mkosi.extra/usr/lib/tmpfiles.d/testuser.conf

@@ -0,0 +1,3 @@

+# SPDX-License-Identifier: LGPL-2.1-or-later

+

+z! /home/testuser 700 testuser testuser

From ec9fd0d4f5f77404fbfabde9e7a9d01aaa1356ff Mon Sep 17 00:00:00 2001

From: Daan De Meyer <daan.j.demeyer@gmail.com>

Date: Wed, 9 Oct 2024 16:37:06 +0200

Subject: [PATCH 2/6] update-utmp: Make reconnect logic more robust

We might also fail to connect to the private manager bus itself if

the daemon-reexec is still ongoing, so let's handle that as well by

retrying on ECONNREFUSED.

---

 src/update-utmp/update-utmp.c | 45 +++++++++++++++++++----------------

 1 file changed, 25 insertions(+), 20 deletions(-)

diff --git a/src/update-utmp/update-utmp.c b/src/update-utmp/update-utmp.c

index c376676e8d0a5..7a8a53f7e8ec5 100644

--- a/src/update-utmp/update-utmp.c

+++ b/src/update-utmp/update-utmp.c

@@ -82,6 +82,25 @@ static int get_current_runlevel(Context *c) {

         assert(c);

         for (unsigned n_attempts = 0;;) {

+                if (n_attempts++ > 0) {

+                        /* systemd might have dropped off momentarily, let's not make this an error,

+                        * and wait some random time. Let's pick a random time in the range 0ms…250ms,

+                        * linearly scaled by the number of failed attempts. */

+                        c->bus = sd_bus_flush_close_unref(c->bus);

+

+                        usec_t usec = random_u64_range(UINT64_C(10) * USEC_PER_MSEC +

+                                                UINT64_C(240) * USEC_PER_MSEC * n_attempts/64);

+                        (void) usleep_safe(usec);

+

+                        r = bus_connect_system_systemd(&c->bus);

+                        if (r == -ECONNREFUSED && n_attempts < 64) {

+                                log_debug_errno(r, "Failed to reconnect to system bus, retrying after a slight delay: %m");

+                                continue;

+                        }

+                        if (r < 0)

+                                return log_error_errno(r, "Failed to reconnect to system bus: %m");

+                }

+

                 FOREACH_ELEMENT(e, table) {

                         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;

                         _cleanup_free_ char *state = NULL, *path = NULL;

@@ -102,18 +121,10 @@ static int get_current_runlevel(Context *c) {

                              sd_bus_error_has_names(&error,

                                                     SD_BUS_ERROR_NO_REPLY,

                                                     SD_BUS_ERROR_DISCONNECTED)) &&

-                            ++n_attempts < 64) {

-

-                                /* systemd might have dropped off momentarily, let's not make this an error,

-                                 * and wait some random time. Let's pick a random time in the range 0ms…250ms,

-                                 * linearly scaled by the number of failed attempts. */

-

-                                usec_t usec = random_u64_range(UINT64_C(10) * USEC_PER_MSEC +

-                                                               UINT64_C(240) * USEC_PER_MSEC * n_attempts/64);

-                                log_debug_errno(r, "Failed to get state of %s, retrying after %s: %s",

-                                                e->special, FORMAT_TIMESPAN(usec, USEC_PER_MSEC), bus_error_message(&error, r));

-                                (void) usleep_safe(usec);

-                                goto reconnect;

+                            n_attempts < 64) {

+                                log_debug_errno(r, "Failed to get state of %s, retrying after a slight delay: %s",

+                                                e->special, bus_error_message(&error, r));

+                                break;

                         }

                         if (r < 0)

                                 return log_warning_errno(r, "Failed to get state of %s: %s", e->special, bus_error_message(&error, r));

@@ -121,14 +132,8 @@ static int get_current_runlevel(Context *c) {

                         if (STR_IN_SET(state, "active", "reloading"))

                                 return e->runlevel;

                 }

-

-                return 0;

-

-reconnect:

-                c->bus = sd_bus_flush_close_unref(c->bus);

-                r = bus_connect_system_systemd(&c->bus);

-                if (r < 0)

-                        return log_error_errno(r, "Failed to reconnect to system bus: %m");

+                if (r >= 0)

+                        return 0;

         }

 }

From a339495b1d67f69f49ffffdd96002164a28f1c93 Mon Sep 17 00:00:00 2001

From: Daan De Meyer <daan.j.demeyer@gmail.com>

Date: Wed, 9 Oct 2024 11:44:34 +0200

Subject: [PATCH 3/6] bus-util: Drop fallback to system/user bus if manager bus

 doesn't work

We have various callsites that explicitly need the manager bus and

won't work with the system bus, like daemon-reexec and friends which

can't properly wait until the operation has finished unless using the

manager bus.

If we silently fall back to the system bus for these operations, we

can end up with rather hard to debug issues so let's remove the fallback

as it was added back in 2013 in a6aa89122d2fa5e811a72200773068c13bfffea2

without a clear explanation of why it was needed (I expect as a fallback

if kdbus wasn't available but that's not a thing anymore these days).

---

 src/shared/bus-util.c | 6 +++---

 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/shared/bus-util.c b/src/shared/bus-util.c

index f4c4eed70702a..44ed617da8dfb 100644

--- a/src/shared/bus-util.c

+++ b/src/shared/bus-util.c

@@ -245,7 +245,7 @@ int bus_connect_system_systemd(sd_bus **ret_bus) {

         r = sd_bus_start(bus);

         if (r < 0)

-                return sd_bus_default_system(ret_bus);

+                return r;

         r = bus_check_peercred(bus);

         if (r < 0)

@@ -265,7 +265,7 @@ int bus_connect_user_systemd(sd_bus **ret_bus) {

         e = secure_getenv("XDG_RUNTIME_DIR");

         if (!e)

-                return sd_bus_default_user(ret_bus);

+                return -ENXIO;

         ee = bus_address_escape(e);

         if (!ee)

@@ -281,7 +281,7 @@ int bus_connect_user_systemd(sd_bus **ret_bus) {

         r = sd_bus_start(bus);

         if (r < 0)

-                return sd_bus_default_user(ret_bus);

+                return r;

         r = bus_check_peercred(bus);

         if (r < 0)

From a178ffdfcd9d25886a6e563a0fbd9929852e85c4 Mon Sep 17 00:00:00 2001

From: Daan De Meyer <daan.j.demeyer@gmail.com>

Date: Wed, 9 Oct 2024 12:10:44 +0200

Subject: [PATCH 4/6] bus-util: Move geteuid() check out of

 bus_connect_system_systemd()

Let's move this check to bus_connect_transport_systemd() so that

bus_connect_system_systemd() will only ever connect to the manager

private manager bus instance and fail otherwise.

---

 src/shared/bus-util.c | 13 ++++++-------

 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/src/shared/bus-util.c b/src/shared/bus-util.c

index 44ed617da8dfb..a196ba47f647c 100644

--- a/src/shared/bus-util.c

+++ b/src/shared/bus-util.c

@@ -229,12 +229,6 @@ int bus_connect_system_systemd(sd_bus **ret_bus) {

         assert(ret_bus);

-        if (geteuid() != 0)

-                return sd_bus_default_system(ret_bus);

-

-        /* If we are root then let's talk directly to the system

-         * instance, instead of going via the bus */

-

         r = sd_bus_new(&bus;;

         if (r < 0)

                 return r;

@@ -521,8 +515,13 @@ int bus_connect_transport_systemd(

                                 /* Print a friendly message when the local system is actually not running systemd as PID 1. */

                                 return log_error_errno(SYNTHETIC_ERRNO(EHOSTDOWN),

                                                        "System has not been booted with systemd as init system (PID 1). Can't operate.");

-                        return bus_connect_system_systemd(ret_bus);

+                        if (geteuid() == 0)

+                                /* If we are root then let's talk directly to the system

+                                 * instance, instead of going via the bus. */

+                                return bus_connect_system_systemd(ret_bus);

+

+                        return sd_bus_default_system(ret_bus);

                 default:

                         assert_not_reached();

                 }

From b066b683539675bc51a71259f1e0f42cef5379ad Mon Sep 17 00:00:00 2001

From: Daan De Meyer <daan.j.demeyer@gmail.com>

Date: Thu, 10 Oct 2024 15:54:37 +0200

Subject: [PATCH 5/6] stdio-bridge: Use bus_log_connect_error()

---

 src/stdio-bridge/stdio-bridge.c | 2 +-

 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/stdio-bridge/stdio-bridge.c b/src/stdio-bridge/stdio-bridge.c

index d3629f5fb0dc5..7b774860c8eb1 100644

--- a/src/stdio-bridge/stdio-bridge.c

+++ b/src/stdio-bridge/stdio-bridge.c

@@ -142,7 +142,7 @@ static int run(int argc, char *argv[]) {

         r = sd_bus_start(a);

         if (r < 0)

-                return log_error_errno(r, "Failed to start bus client: %m");

+                return bus_log_connect_error(r, arg_transport, arg_runtime_scope);

         r = sd_bus_get_bus_id(a, &server_id);

         if (r < 0)

From d94e85c2279ac255a9c964046723684ca99b7f00 Mon Sep 17 00:00:00 2001

From: Daan De Meyer <daan.j.demeyer@gmail.com>

Date: Thu, 10 Oct 2024 15:54:57 +0200

Subject: [PATCH 6/6] stdio-bridge: Use customized log message for forwarding

 bus

Let's more clearly indicate that we failed to set up the server

which forwards messages from the remote client to the local bus

instead of logging a generic bus client message.

---

 src/stdio-bridge/stdio-bridge.c | 2 +-

 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/stdio-bridge/stdio-bridge.c b/src/stdio-bridge/stdio-bridge.c

index 7b774860c8eb1..22570511cbabb 100644

--- a/src/stdio-bridge/stdio-bridge.c

+++ b/src/stdio-bridge/stdio-bridge.c

@@ -170,7 +170,7 @@ static int run(int argc, char *argv[]) {

         r = sd_bus_start(b);

         if (r < 0)

-                return log_error_errno(r, "Failed to start bus client: %m");

+                return log_error_errno(r, "Failed to start bus forwarding server: %m");

         for (;;) {

                 _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL;