1 files changed, 68 insertions, 0 deletions
diff --git a/debian/gdm3.preinst b/debian/gdm3.preinst
new file mode 100644
index 0000000..93ebed9
--- /dev/null
+++ b/debian/gdm3.preinst
@@ -0,0 +1,68 @@
+#!/bin/sh
+
+set -e
+
+if [ "$1" = "upgrade" ] || [ "$1" = "install" ]; then
+  # Remove wrongly replaced custom.config file by versions > 3.37.90 && < 3.38.1
+  # This script can be safely removed post 20.10 release
+  prev_version="$2"
+  if dpkg --compare-versions "$prev_version" ge 3.37.90 &&
+     dpkg --compare-versions "$prev_version" lt-nl 3.38.1; then
+    conf_file=/etc/gdm3/daemon.conf
+    if [ "${prev_version#*ubuntu}" != "$prev_version" ]; then
+      conf_file=/etc/gdm3/custom.conf
+    fi
+
+    conf="${DPKG_ROOT}$conf_file"
+    if [ -f "$conf" ] &&
+       echo "ed0a2d19ba7344faa0feadd783bb4fa5 $conf" | md5sum -c --status; then
+      # If the file matches this checksum, then it's a file generated by
+      # /usr/libexec/gdm-disable-wayland that was wrongly replaced, so we
+      # replace the conf file to match the one that was default in these
+      # broken versions, so that dpkg would replace it in case.
+      echo "Configuration file $conf_file has likely been damaged by" \
+        "https://pad.lv/1899673, replacing with the gdm default..."
+      cat <<'EOF' > "$conf"
+# GDM configuration storage
+#
+# See /usr/share/gdm/gdm.schemas for a list of available options.
+
+[daemon]
+# Uncomment the line below to force the login screen to use Xorg
+#WaylandEnable=false
+
+# Enabling automatic login
+#  AutomaticLoginEnable = true
+#  AutomaticLogin = user1
+
+# Enabling timed login
+#  TimedLoginEnable = true
+#  TimedLogin = user1
+#  TimedLoginDelay = 10
+
+[security]
+
+[xdmcp]
+
+[chooser]
+
+[debug]
+# Uncomment the line below to turn on debugging
+# More verbose logs
+# Additionally lets the X server dump core if it crashes
+#Enable=true
+
+EOF
+
+      # Verify that the file we've just added matches the default one
+      # We don't fail as it's not a fatal error, but will cause manual
+      # intervention at later points
+      default_md5sum="$(dpkg-query -W -f='${Conffiles}' gdm3 | \
+       sed -n -e "\\'^ $conf_file ' { s/ obsolete$//; s/.* //; p }")"
+      echo "$default_md5sum $conf" | md5sum -c --status ||
+        echo "Replaced configuration file isn't matching expected default"
+    fi
+  fi
+fi
+
+#DEBHELPER#