Bug#1053301: udev.postinst removes valid /etc/rc*.d/ symlinks

[Mark Hindley]

Control: tags -1 patch
Control: affects -1 initscripts
Control: severity -1 serious
Justification: Breaks unrelated packages, breaks non-systemd boot

Michael,

Please find a patch below that addresses this issue in my test setup. I can
offer to NMU if you would like?

I have provided an easy means to reproduce the bug and a clear justfication for
why I think this is an RC bug. If you disagree, please explain why, rather than
just changing the severity. Thanks.

Best wishes

Mark

diff --git a/debian/changelog b/debian/changelog
index fe1f4bc..ec8a75a 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,12 @@
+systemd (254.5-1.1) UNRELEASED; urgency=medium
+
+  * Non-maintainer upload.
+  * d/udev.postinst: Correct version number test for dropping
+    /etc/init.d/udev and only remove /etc/rc?.d/symlinks if
+    /etc/init.d/udev doesn't exist.  (Closes: #1053301)
+
+ -- Mark Hindley <leepen at debian.org>  Wed, 04 Oct 2023 18:30:36 +0100
+
 systemd (254.5-1) unstable; urgency=medium
 
   * New upstream version 254.5
diff --git a/debian/udev.postinst b/debian/udev.postinst
index 84ff782..04bafa2 100644
--- a/debian/udev.postinst
+++ b/debian/udev.postinst
@@ -11,7 +11,8 @@ case "$1" in
         # update/create hwdb before we (re)start udev
         update_hwdb
 
-        if dpkg --compare-versions "$2" lt-nl "254.1-4~"; then
+        if dpkg --compare-versions "$2" lt-nl "254.3-1~" &&
+                [ ! -f /etc/init.d/udev ] ; then
             update-rc.d udev remove || true
         fi
     ;;