Reintroduce systemd patches to fix hostname configuration (#1617)

Even though upstream changed the way hostname gets set, it still
requires changes to make it work on a bind mounted /etc/hostname file.

buildroot-external/patches/systemd/0001-time-wait-sync-log-errors-trying-to-watch-run-system.patch

@@ -0,0 +1,27 @@
+From 2214c1f039143caaf4ed99eb0f3fc4551b322148 Mon Sep 17 00:00:00 2001
+Message-Id: <2214c1f039143caaf4ed99eb0f3fc4551b322148.1635377266.git.stefan@agner.ch>
+From: Aman Gupta Karmani <aman@tmm1.net>
+Date: Mon, 12 Oct 2020 13:39:26 -0700
+Subject: [PATCH 1/2] time-wait-sync: log errors trying to watch
+ /run/systemd/timesync
+
+---
+ src/timesync/wait-sync.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/src/timesync/wait-sync.c b/src/timesync/wait-sync.c
+index 2a9b113ff4..62fa13c509 100644
+--- a/src/timesync/wait-sync.c
++++ b/src/timesync/wait-sync.c
+@@ -44,7 +44,7 @@ static void clock_state_release(ClockState *sp) {
+ static int clock_state_update(ClockState *sp, sd_event *event);
+ 
+ static int update_notify_run_systemd_timesync(ClockState *sp) {
+-        sp->run_systemd_timesync_wd = inotify_add_watch(sp->inotify_fd, "/run/systemd/timesync", IN_CREATE|IN_DELETE_SELF);
++        sp->run_systemd_timesync_wd = inotify_add_watch_and_warn(sp->inotify_fd, "/run/systemd/timesync", IN_CREATE|IN_DELETE_SELF);
+         return sp->run_systemd_timesync_wd;
+ }
+ 
+-- 
+2.33.1
+

buildroot-external/patches/systemd/0002-hostnamed-allow-hostname-change-on-read-only-etc.patch

@@ -0,0 +1,59 @@
+From e38f7d9c364f91bba09979c841b9e33dbeae686d Mon Sep 17 00:00:00 2001
+Message-Id: <e38f7d9c364f91bba09979c841b9e33dbeae686d.1635377266.git.stefan@agner.ch>
+In-Reply-To: <2214c1f039143caaf4ed99eb0f3fc4551b322148.1635377266.git.stefan@agner.ch>
+References: <2214c1f039143caaf4ed99eb0f3fc4551b322148.1635377266.git.stefan@agner.ch>
+From: Stefan Agner <stefan@agner.ch>
+Date: Wed, 27 Oct 2021 22:24:47 +0200
+Subject: [PATCH 2/2] hostnamed: allow hostname change on read-only /etc
+
+The implementation of write_string_file_atomic_label() uses atomic write
+operation, which tries to create a file in /etc. Use regular file
+operation with sync flag to make sure the hostname is written to disk
+immediately.
+
+Signed-off-by: Stefan Agner <stefan@agner.ch>
+---
+ src/hostname/hostnamed.c | 10 +++++++++-
+ 1 file changed, 9 insertions(+), 1 deletion(-)
+
+diff --git a/src/hostname/hostnamed.c b/src/hostname/hostnamed.c
+index bd535ddc4d..0ec57eb2a7 100644
+--- a/src/hostname/hostnamed.c
++++ b/src/hostname/hostnamed.c
+@@ -15,6 +15,7 @@
+ #include "env-file-label.h"
+ #include "env-file.h"
+ #include "env-util.h"
++#include "fd-util.h"
+ #include "fileio-label.h"
+ #include "fileio.h"
+ #include "hostname-setup.h"
+@@ -379,6 +380,7 @@ static void unset_statp(struct stat **p) {
+ 
+ static int context_write_data_static_hostname(Context *c) {
+         _cleanup_(unset_statp) struct stat *s = NULL;
++        _cleanup_close_ int fd = -1;
+         int r;
+ 
+         assert(c);
+@@ -395,10 +397,16 @@ static int context_write_data_static_hostname(Context *c) {
+                 return 0;
+         }
+ 
+-        r = write_string_file_atomic_label("/etc/hostname", c->data[PROP_STATIC_HOSTNAME]);
++        r = write_string_file("/etc/hostname", c->data[PROP_STATIC_HOSTNAME],
++                              WRITE_STRING_FILE_CREATE | WRITE_STRING_FILE_TRUNCATE);
+         if (r < 0)
+                 return r;
+ 
++        /* Cannot use WRITE_STRING_FILE_SYNC as it tries to sync parent dir */
++        fd = open("/etc/hostname", O_RDONLY|O_CLOEXEC);
++        if (fsync(fd) < 0)
++                return -errno;
++
+         TAKE_PTR(s);
+         return 0;
+ }
+-- 
+2.33.1
+