diff --git a/pkg/de-p1st-installer/lib/block-device.sh b/pkg/de-p1st-installer/lib/block-device.sh
index a16cfdf..b6d8f28 100644
--- a/pkg/de-p1st-installer/lib/block-device.sh
+++ b/pkg/de-p1st-installer/lib/block-device.sh
@@ -102,4 +102,4 @@ function partition() {
 		return 1
 		;;
   esac
-}
\ No newline at end of file
+}
diff --git a/pkg/de-p1st-installer/lib/user-input.sh b/pkg/de-p1st-installer/lib/user-input.sh
index d6104e0..c07d83e 100644
--- a/pkg/de-p1st-installer/lib/user-input.sh
+++ b/pkg/de-p1st-installer/lib/user-input.sh
@@ -16,7 +16,7 @@ function get_text_input {
     fi
   done
 
-  local -n ptr=$1
+  local -n ptr=$1 || return $?
   if [ -z "$ptr" ]; then
     # if ptr has no value yet, ask user for input!
     echo "$2"
@@ -48,11 +48,11 @@ function get_single_choice {
   done
 
 
-  local -n ptr=$1
+  local -n ptr=$1 || return $?
   if [ -z "$ptr" ]; then
     # if ptr has no value yet, ask user for input!
 
-    local -n MENU_OPTIONS=$3
+    local -n MENU_OPTIONS=$3 || return $?
     ptr=$(dialog --stdout --menu "$2" 0 0 0 "${MENU_OPTIONS[@]}") || {
       echo "Error during menu selection!"
       exit 1
@@ -79,11 +79,11 @@ function get_multi_choice {
   done
 
 
-  local -n ptr=$1
+  local -n ptr=$1 || return $?
   if [ -z "$ptr" ]; then
     # if ptr has no value yet, ask user for input!
 
-    local -n MENU_OPTIONS=$3
+    local -n MENU_OPTIONS=$3 || return $?
     TMP1=$(dialog --stdout --checklist "$2" 0 0 0 "${MENU_OPTIONS[@]}") || {
       echo "Error during menu selection!"
       exit 1
diff --git a/pkg/de-p1st-installer/lib/util.sh b/pkg/de-p1st-installer/lib/util.sh
index 48357eb..c7a3711 100644
--- a/pkg/de-p1st-installer/lib/util.sh
+++ b/pkg/de-p1st-installer/lib/util.sh
@@ -2,7 +2,7 @@ function newline_to_space() {
   # Replaces all newlines with spaces
   # $1: name of variable
 
-  local -n ptr=$1
+  local -n ptr=$1 || return $?
   # Replace newlines with spaces
   # See bash string substitution: https://gist.github.com/JPvRiel/b279524d3e56229a896477cb8082a72b
 
@@ -18,8 +18,8 @@ function newline_separated_to_array() {
   # $1: name of variable with newline separated list
   # $2: name of array to store values into
 
-  local -n ptr=$1
-  local -n ptr2=$2
+  local -n ptr=$1  || return $?
+  local -n ptr2=$2 || return $?
   # ptr newline separated list.
   # Store this as array ptr2.
   readarray -t ptr2 <<<"$ptr"
@@ -29,8 +29,8 @@ function space_separated_to_array() {
   # $1: name of variable with space separated list
   # $2: name of array to store values into
 
-  local -n ptr=$1
-  local -n ptr2=$2
+  local -n ptr=$1  || return $?
+  local -n ptr2=$2 || return $?
   # ptr space separated list.
   # Store this as array ptr2.
   # Without newline at last array element: https://unix.stackexchange.com/a/519917/315162
diff --git a/pkg/de-p1st-installer/name-reference-test.sh b/pkg/de-p1st-installer/name-reference-test.sh
index f816fdd..3efba7a 100644
--- a/pkg/de-p1st-installer/name-reference-test.sh
+++ b/pkg/de-p1st-installer/name-reference-test.sh
@@ -18,7 +18,7 @@ function text_input {
     return 1
   fi
 
-  local -n ptr=$1
+  local -n ptr=$1 || return $?
   if [ -z "$ptr" ]; then
     echo "$2"
     read -r ptr || return $?