debian/changelog

+glibc (2.38-12) UNRELEASED; urgency=medium
+
+  [ Aurelien Jarno ]
+  * debian/debhelper.in/libc.postinst: do not try to call telinit if it is
+    provided by systemd, it is just broken.  Closes: #1071462.
+  * debian/debhelper.in/libc.postinst: test for $DPKG_ROOT first.
+
+ -- Aurelien Jarno <aurel32@debian.org>  Sat, 01 Jun 2024 19:40:58 +0200
+
 glibc (2.38-11) unstable; urgency=medium
   [ Aurelien Jarno ]

debian/debhelper.in/libc.postinst

@@ -151,12 +151,12 @@ then
     # assumes anything else is going to not fail at behaving like
     # sysvinit:
     TELINIT=yes
-    if ischroot 2>/dev/null; then
-        # Don't bother trying to re-exec init from a chroot:
-        TELINIT=no
-    elif [ -n "${DPKG_ROOT:-}" ]; then
+    if [ -n "${DPKG_ROOT:-}" ]; then
         # Do not re-exec init if we are operating on a chroot from outside:
         TELINIT=no
+    elif ischroot 2>/dev/null; then
+        # Don't bother trying to re-exec init from a chroot:
+        TELINIT=no
     elif [ -d /run/systemd/system ]; then
         # Restart systemd on upgrade, but carefully.
         # The restart is wanted because of LP: #1942276 and Bug: #993821
@@ -170,6 +170,13 @@ then
         else
             echo "Error: Could not restart systemd, systemd binary not working" >&2
         fi
+    elif ! command -v telinit >/dev/null; then
+        # There is not telinit binary:
+        TELINIT=no
+    elif readlink $(command -v telinit) | grep -q systemctl; then
+        # Systemd's telinit tends to do bad things (#1063147, #1071462), so
+        # just ignore that case:
+        TELINIT=no
     fi
     if [ "$TELINIT" = "yes" ]; then
         telinit u 2>/dev/null || true ; sleep 1