Merge ~enr0n/ubuntu/+source/systemd:ubuntu-kinetic into ~ubuntu-core-dev/ubuntu/+source/systemd:ubuntu-kinetic

[Nick Rosbrook]

These changes are needed in kinetic ahead of a Jammy SRU.

[Lukas Märdian (slyon)]

Thank you, Nick. This looks good to me. Please remember to mention a test build/PPA (and potential autopkgtest) of your changes for next time. I think I found a test build in your PPA for now: https://launchpad.net/~enr0n/+archive/ubuntu/systemd-251/+packages

I am a bit reluctant about adding even more /etc/writable workarounds for Ubuntu Core, but I understand that we need this now. Last time, I asked the snapd team to come up with a more sustainable solution for this issue (LP: #1953172) but I think nothing came out of this up to now.. (Thanks for also mentioning this bug in the patch headers!)

Medium term, I think we should probably move that "writable_filename()" function to a more global place inside systemd (maybe some utils file inside libsystemd, that is available to all components applying this workaround? Or a new "ubuntu-quirks.h" header that we include from all those modules?) – I'm not sure if such place exists, but it might be cleaner than copying the same static function into all those modules. We could then consolidate the 3 patches into a single, smaller one:
- debian/patches/debian/UBUNTU-Support-system-image-read-only-etc.patch
- debian/patches/debian/UBUNTU-Fix-timezone-setting-on-read-only-etc.patch
- debian/patches/lp1981042-core-firstboot-workaround-timezone-issues-caused-by-Ubunt.patch

=> But this shall not block this upload.

Long term, I still hope we (or the snapd team) get somewhere with LP: #1953172

review: Approve

diff --git a/debian/changelog b/debian/changelog
index 641bbcd..9d6a334 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,10 +1,20 @@
-systemd (251.2-2ubuntu2) UNRELEASED; urgency=medium
+systemd (251.2-2ubuntu2) kinetic; urgency=medium
 
+  [ Lukas Märdian ]
   * Remove restart limit on the modprobe@.service (LP: #1982462)
     File: debian/patches/units-remove-the-restart-limit-on-the-modprobe-.service.patch
     https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=46c36d4c73df8980f6b6137142fb16ba90465a94
 
- -- Lukas Märdian <[e-mail]>  Thu, 21 Jul 2022 11:06:52 +0200
+  [ Nick Rosbrook ]
+  * core,firstboot: workaround timezone issues on Ubuntu Core (LP: #1981042)
+    Thanks to Robert Ancell for preparing the patch.
+    File: debian/patches/lp1981042-core-firstboot-workaround-timezone-issues-caused-by-Ubunt.patch
+    https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=9a435d43e753f39531c9a5517a85e8eb259e18f1
+  * pstore: do not try to load mtdpstore (LP: #1981622)
+    File: debian/patches/lp1978079-pstore-Run-after-modules-are-loaded.patch
+    https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=38d8d12be924477f0eecb64f3737e07b03d73a42
+
+ -- Nick Rosbrook <[e-mail]>  Fri, 22 Jul 2022 15:23:45 -0400
 
 systemd (251.2-2ubuntu1) kinetic; urgency=medium
 
diff --git a/debian/patches/lp1978079-pstore-Run-after-modules-are-loaded.patch b/debian/patches/lp1978079-pstore-Run-after-modules-are-loaded.patch
index 7c6c737..e7b7194 100644
--- a/debian/patches/lp1978079-pstore-Run-after-modules-are-loaded.patch
+++ b/debian/patches/lp1978079-pstore-Run-after-modules-are-loaded.patch
@@ -4,7 +4,12 @@ Subject: pstore: Run after modules are loaded
 
 Origin: upstream, https://github.com/systemd/systemd/commit/70e74a5997ae2ce7ba72a74ac949c3b2dad1a1d6
 Bug-Ubuntu: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1978079
+Bug-Ubuntu: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1981622
+Last-Updated: 2022-07-22
 
+The original commit has been modified to not load mtdpstore.
+
+---
 The systemd-pstore service takes pstore files on boot and transfers them
 to disk. It only does it once on boot and only if it finds any. The typical
 location of the pstore on modern systems is the UEFI variable store.
@@ -36,8 +41,8 @@ index 848e311..86de30a 100644
  DefaultDependencies=no
  Conflicts=shutdown.target
  Before=sysinit.target shutdown.target
-+After=modprobe@efi_pstore.service [e-mail] modprobe@chromeos_pstore.service [e-mail] modprobe@pstore_zone.service modprobe@pstore_blk.service
-+Wants=modprobe@efi_pstore.service [e-mail] modprobe@chromeos_pstore.service [e-mail] modprobe@pstore_zone.service modprobe@pstore_blk.service
++After=modprobe@efi_pstore.service modprobe@chromeos_pstore.service [e-mail] modprobe@pstore_zone.service modprobe@pstore_blk.service
++Wants=modprobe@efi_pstore.service modprobe@chromeos_pstore.service [e-mail] modprobe@pstore_zone.service modprobe@pstore_blk.service
  
  [Service]
  Type=oneshot
diff --git a/debian/patches/lp1981042-core-firstboot-workaround-timezone-issues-caused-by-Ubunt.patch b/debian/patches/lp1981042-core-firstboot-workaround-timezone-issues-caused-by-Ubunt.patch
new file mode 100644
index 0000000..7d64066
--- /dev/null
+++ b/debian/patches/lp1981042-core-firstboot-workaround-timezone-issues-caused-by-Ubunt.patch
@@ -0,0 +1,110 @@
+Description: Workaround timezone issues cause by Ubuntu Core's read-only /etc
+ This is another patch in a series of existing ones working around this issue
+ on Ubuntu Core.
+Author: Nick Rosbrook <[e-mail]>
+Bug-Ubuntu: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1981042
+Bug-Ubuntu: https://bugs.launchpad.net/snappy/+bug/1953172
+Forwarded: not-needed (part of read-only /etc workaround)
+Last-Update: 2022-07-20
+---
+diff --git a/src/core/manager.c b/src/core/manager.c
+index 296b759..230e5c8 100644
+--- a/src/core/manager.c
++++ b/src/core/manager.c
+@@ -424,6 +424,25 @@ static int manager_setup_time_change(Manager *m) {
+         return 0;
+ }
+ 
++/* Hack for Ubuntu Phone/Core: check if path is an existing symlink to
++ * /etc/writable; if it is, update that instead */
++static const char* writable_filename(const char *path) {
++        ssize_t r;
++        static char realfile_buf[PATH_MAX];
++        _cleanup_free_ char *realfile = NULL;
++        const char *result = path;
++        int orig_errno = errno;
++
++        r = readlink_and_make_absolute(path, &realfile);
++        if (r >= 0 && startswith(realfile, "/etc/writable")) {
++                snprintf(realfile_buf, sizeof(realfile_buf), "%s", realfile);
++                result = realfile_buf;
++        }
++
++        errno = orig_errno;
++        return result;
++}
++
+ static int manager_read_timezone_stat(Manager *m) {
+         struct stat st;
+         bool changed;
+@@ -431,7 +450,7 @@ static int manager_read_timezone_stat(Manager *m) {
+         assert(m);
+ 
+         /* Read the current stat() data of /etc/localtime so that we detect changes */
+-        if (lstat("/etc/localtime", &st) < 0) {
++        if (lstat(writable_filename("/etc/localtime"), &st) < 0) {
+                 log_debug_errno(errno, "Failed to stat /etc/localtime, ignoring: %m");
+                 changed = m->etc_localtime_accessible;
+                 m->etc_localtime_accessible = false;
+@@ -468,7 +487,7 @@ static int manager_setup_timezone_change(Manager *m) {
+          * Note that we create the new event source first here, before releasing the old one. This should optimize
+          * behaviour as this way sd-event can reuse the old watch in case the inode didn't change. */
+ 
+-        r = sd_event_add_inotify(m->event, &new_event, "/etc/localtime",
++        r = sd_event_add_inotify(m->event, &new_event, writable_filename("/etc/localtime"),
+                                  IN_ATTRIB|IN_MOVE_SELF|IN_CLOSE_WRITE|IN_DONT_FOLLOW, manager_dispatch_timezone_change, m);
+         if (r == -ENOENT) {
+                 /* If the file doesn't exist yet, subscribe to /etc instead, and wait until it is created either by
+diff --git a/src/firstboot/firstboot.c b/src/firstboot/firstboot.c
+index 3916018..9f2d178 100644
+--- a/src/firstboot/firstboot.c
++++ b/src/firstboot/firstboot.c
+@@ -462,18 +462,37 @@ static int prompt_timezone(void) {
+         return 0;
+ }
+ 
++/* Hack for Ubuntu Phone/Core: check if path is an existing symlink to
++ * /etc/writable; if it is, update that instead */
++static const char* writable_filename(const char *path) {
++        ssize_t r;
++        static char realfile_buf[PATH_MAX];
++        _cleanup_free_ char *realfile = NULL;
++        const char *result = path;
++        int orig_errno = errno;
++
++        r = readlink_and_make_absolute(path, &realfile);
++        if (r >= 0 && startswith(realfile, "/etc/writable")) {
++                snprintf(realfile_buf, sizeof(realfile_buf), "%s", realfile);
++                result = realfile_buf;
++        }
++
++        errno = orig_errno;
++        return result;
++}
++
+ static int process_timezone(void) {
+         const char *etc_localtime, *e;
+         int r;
+ 
+-        etc_localtime = prefix_roota(arg_root, "/etc/localtime");
++        etc_localtime = prefix_roota(arg_root, writable_filename("/etc/localtime"));
+         if (laccess(etc_localtime, F_OK) >= 0 && !arg_force)
+                 return 0;
+ 
+         if (arg_copy_timezone && arg_root) {
+                 _cleanup_free_ char *p = NULL;
+ 
+-                r = readlink_malloc("/etc/localtime", &p);
++                r = readlink_malloc(writable_filename("/etc/localtime"), &p);
+                 if (r != -ENOENT) {
+                         if (r < 0)
+                                 return log_error_errno(r, "Failed to read host timezone: %m");
+@@ -494,7 +513,7 @@ static int process_timezone(void) {
+         if (isempty(arg_timezone))
+                 return 0;
+ 
+-        e = strjoina("../usr/share/zoneinfo/", arg_timezone);
++        e = strjoina("/usr/share/zoneinfo/", arg_timezone);
+ 
+         (void) mkdir_parents(etc_localtime, 0755);
+         if (symlink(e, etc_localtime) < 0)
diff --git a/debian/patches/series b/debian/patches/series
index 0824f07..3cc9601 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -49,3 +49,4 @@ hwdb-implement-root-option-for-systemd-hwdb-query.patch
 test-increase-QEMU_MEM-for-some-tests.patch
 test-copy-libgcc_s.so.1-to-TPM2-test-image-on-Debian-like.patch
 units-remove-the-restart-limit-on-the-modprobe-.service.patch
+lp1981042-core-firstboot-workaround-timezone-issues-caused-by-Ubunt.patch