Merge ~peat-new/ubuntu/+source/systemd:ubuntu-bionic_-_timedated-symlink into ~ubuntu-core-dev/ubuntu/+source/systemd:ubuntu-bionic

[Ratchanan Srirattanamet]

Fix timedated unable to retrieve & properly set timezone on read-only /etc

LP: #1650688
LP: #1733881

diff --git a/debian/changelog b/debian/changelog
index 5e2e2aa..eeb41da 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,13 @@
+systemd (237-3ubuntu10.53) UNRELEASED; urgency=medium
+
+  * d/p/debian/timedatectl-lp1650688.patch,
+    d/p/debian/UBUNTU-Fix-timezone-setting-on-read-only-etc.patch:
+    Fix timedated unable to retrieve & properly set timezone on
+    read-only /etc (e.g. Ubuntu Core and system-image-based systems)
+    (LP: #1650688, LP: #1733881)
+
+ -- Ratchanan Srirattanamet <[e-mail]>  Fri, 24 Sep 2021 16:54:31 +0700
+
 systemd (237-3ubuntu10.52) bionic; urgency=medium
 
   * d/extra/dhclient-enter-resolved-hook:
diff --git a/debian/patches/debian/UBUNTU-Fix-timezone-setting-on-read-only-etc.patch b/debian/patches/debian/UBUNTU-Fix-timezone-setting-on-read-only-etc.patch
new file mode 100644
index 0000000..61841f4
--- /dev/null
+++ b/debian/patches/debian/UBUNTU-Fix-timezone-setting-on-read-only-etc.patch
@@ -0,0 +1,25 @@
+Description: Fix timezone setting on read-only etc
+ Due to our read-only /etc workaround, the localtime link on such
+ system ends up in /etc/writable, not /etc. To make the link target
+ correct in both normal and such systems, makes the path absolute.
+ .
+ On Ubuntu Core, this eliminates the need for the wrapper script, and
+ makes the DBus interface work properly.
+Author: Ratchanan Srirattanamet <[e-mail]>
+Origin: other
+Bug-Ubuntu: https://bugs.launchpad.net/snappy/+bug/1650688
+Forwarded: not-needed (part of read-only /etc workaround)
+Last-Update: 2021-09-24
+---
+This patch header follows DEP-3: http://dep.debian.net/deps/dep3/
+--- a/src/timedate/timedated.c
++++ b/src/timedate/timedated.c
+@@ -118,7 +118,7 @@
+                 return r;
+         }
+ 
+-        p = strappend("../usr/share/zoneinfo/", c->zone);
++        p = strappend("/usr/share/zoneinfo/", c->zone);
+         if (!p)
+                 return log_oom();
+ 
diff --git a/debian/patches/debian/timedatectl-lp1650688.patch b/debian/patches/debian/timedatectl-lp1650688.patch
new file mode 100644
index 0000000..f5ab19e
--- /dev/null
+++ b/debian/patches/debian/timedatectl-lp1650688.patch
@@ -0,0 +1,51 @@
+Description: Fix retrieving timezone on read-only /etc
+ get_timezone() retrieve it by reading the link destination of
+ /etc/localtime, which on systems with read-only /etc will always point
+ to /etc/writable. Makes this function aware of the /etc/writable
+ redirection and handle it.
+ .
+ [[e-mail]: add descrtiption and other metadata.]
+ [[e-mail]: backport the patch for bionic]
+Author: Michael Vogt <[e-mail]>
+Origin: backport, https://bugs.launchpad.net/snappy/+bug/1650688/comments/46
+Bug-Ubuntu: https://bugs.launchpad.net/snappy/+bug/1650688
+Forwarded: not-needed (part of read-only /etc workaround)
+Last-Update: 2021-09-24
+---
+This patch header follows DEP-3: http://dep.debian.net/deps/dep3/
+--- a/src/basic/time-util.c
++++ b/src/basic/time-util.c
+@@ -1380,13 +1380,32 @@
+         }
+ }
+ 
++/* Hack for Ubuntu phone: 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;
++}
++
+ int get_timezone(char **tz) {
+         _cleanup_free_ char *t = NULL;
+         const char *e;
+         char *z;
+         int r;
+ 
+-        r = readlink_malloc("/etc/localtime", &t);
++        r = readlink_malloc(writable_filename("/etc/localtime"), &t);
+         if (r < 0) {
+                 if (r != -EINVAL)
+                         return r; /* returns EINVAL if not a symlink */
diff --git a/debian/patches/series b/debian/patches/series
index 093231f..746c816 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -97,6 +97,8 @@ sd-bus-if-we-receive-an-invalid-dbus-message-ignore-.patch
 journal-do-not-remove-multiple-spaces-after-identifi.patch
 stop-mount-error-propagation.patch
 Support-system-image-read-only-etc.patch
+debian/timedatectl-lp1650688.patch
+debian/UBUNTU-Fix-timezone-setting-on-read-only-etc.patch
 fix-race-daemon-reload-11121.patch
 virt-detect-WSL-environment-as-a-container-id-wsl.patch
 CVE-2019-3842.patch