diff --git a/hack/lib/util.sh b/hack/lib/util.sh
index b106a1998d9..e6cada20eca 100755
--- a/hack/lib/util.sh
+++ b/hack/lib/util.sh
@@ -413,11 +413,11 @@ kube::util::has_changes_against_upstream_branch() {
     exit 1
   fi
   # notice this uses ... to find the first shared ancestor
-  if git diff --name-only "${full_branch}...HEAD" | grep -v "${not_pattern}" | grep "${pattern}" > /dev/null; then
+  if git diff --name-only "${full_branch}...HEAD" | grep -v -E "${not_pattern}" | grep "${pattern}" > /dev/null; then
     return 0
   fi
   # also check for pending changes
-  if git status --porcelain | grep -v "${not_pattern}" | grep "${pattern}" > /dev/null; then
+  if git status --porcelain | grep -v -E "${not_pattern}" | grep "${pattern}" > /dev/null; then
     echo "Detected '${pattern}' uncommitted changes."
     return 0
   fi
diff --git a/hack/verify-readonly-packages.sh b/hack/verify-readonly-packages.sh
index 02d8d5745d8..957a970caf5 100755
--- a/hack/verify-readonly-packages.sh
+++ b/hack/verify-readonly-packages.sh
@@ -45,7 +45,7 @@ find_files() {
 IFS=$'\n'
 conflicts=($(find_files | sed 's|/.readonly||' | while read dir; do
     dir=${dir#./}
-    if kube::util::has_changes_against_upstream_branch "${branch}" "^${dir}/[^/]*\$" "/.readonly\$" &>/dev/null; then
+    if kube::util::has_changes_against_upstream_branch "${branch}" "^${dir}/[^/]*\$" "/.readonly\$|/BUILD$|/zz_generated" &>/dev/null; then
         echo "${dir}"
     fi
 done))