diff --git a/shared/macros/10-bash.jinja b/shared/macros/10-bash.jinja
index f1c1c2502bc..7ea3235fca0 100644
--- a/shared/macros/10-bash.jinja
+++ b/shared/macros/10-bash.jinja
@@ -1722,10 +1722,10 @@ Ensures that given mount point is in :code:`/etc/fstab`.
 
 #}}
 {{% macro bash_ensure_mount_option_in_fstab(mount_point, mount_opt, fs_spec, type) -%}}
-mount_point_match_regexp="$(printf "[^#].*[[:space:]]%s[[:space:]]" {{{ mount_point }}})"
+mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" {{{ mount_point }}})"
 
 # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
-if ! grep "$mount_point_match_regexp" /etc/fstab; then
+if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
     # runtime opts without some automatic kernel/userspace-added defaults
     previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                 | sed -E "s/(rw|defaults|seclabel|{{{ mount_opt }}})(,|$)//g;s/,$//")
@@ -1738,7 +1738,7 @@ if ! grep "$mount_point_match_regexp" /etc/fstab; then
     fi
     echo "{{{ fs_spec }}} {{{ mount_point }}} {{{ type }}} defaults,${previous_mount_opts}{{{ mount_opt }}} 0 0" >> /etc/fstab
 # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
-elif ! grep "$mount_point_match_regexp" /etc/fstab | grep "{{{ mount_opt }}}"; then
+elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "{{{ mount_opt }}}"; then
     previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
     sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,{{{ mount_opt }}}|" /etc/fstab
 fi
@@ -1750,7 +1750,7 @@ fi
 
 #}}
 {{% macro bash_assert_mount_point_in_fstab(mount_point) -%}}
-mount_point_match_regexp="$(printf "[^#].*[[:space:]]%s[[:space:]]" "{{{ mount_point }}}")"
+mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "{{{ mount_point }}}")"
 {{#
     This macro gets expanded to code that will return 1 if MOUNTPOINT is not in /etc/fstab;
     This is consistent with the behavior prior to converting this function to a jinja macro
diff --git a/shared/templates/mount_option/tests/fstab_commented_correct_then_uncommented_wrong.fail.sh b/shared/templates/mount_option/tests/fstab_commented_correct_then_uncommented_wrong.fail.sh
new file mode 100644
index 00000000000..54c5cc8c5dd
--- /dev/null
+++ b/shared/templates/mount_option/tests/fstab_commented_correct_then_uncommented_wrong.fail.sh
@@ -0,0 +1,16 @@
+#!/bin/bash
+
+# platform = multi_platform_all
+. $SHARED/partition.sh
+
+clean_up_partition {{{ MOUNTPOINT }}}
+
+create_partition
+make_fstab_given_partition_line {{{ MOUNTPOINT }}} ext2 {{{ MOUNTOPTION }}}
+
+# comment last line added above to be ignored
+sed -Ei '${s/^/#/}' /etc/fstab
+
+make_fstab_given_partition_line {{{ MOUNTPOINT }}} ext2 defaults
+
+mount_partition {{{ MOUNTPOINT }}} || true