Fixed issue where the modify script for raw images could not be executed

pkg/build/build.go

@@ -138,14 +138,14 @@ func (b *Builder) generateCombustionScript() error {
 	return nil
 }
 
-func (b *Builder) writeBuildDirFile(filename string, contents string, templateData any) error {
+func (b *Builder) writeBuildDirFile(filename string, contents string, templateData any) (string, error) {
 	destFilename := filepath.Join(b.eibBuildDir, filename)
-	return b.writeFile(destFilename, contents, templateData)
+	return destFilename, b.writeFile(destFilename, contents, templateData)
 }
 
-func (b *Builder) writeCombustionFile(filename string, contents string, templateData any) error {
+func (b *Builder) writeCombustionFile(filename string, contents string, templateData any) (string, error) {
 	destFilename := filepath.Join(b.combustionDir, filename)
-	return b.writeFile(destFilename, contents, templateData)
+	return destFilename, b.writeFile(destFilename, contents, templateData)
 }
 
 func (b *Builder) writeFile(filename string, contents string, templateData any) error {

pkg/build/build_test.go

@@ -122,14 +122,15 @@ func TestWriteCombustionFile(t *testing.T) {
 	testFilename := "combustion-file.sh"
 
 	// Test
-	err = builder.writeCombustionFile(testFilename, testData, nil)
+	writtenFilename, err := builder.writeCombustionFile(testFilename, testData, nil)
 
 	// Verify
 	require.NoError(t, err)
 
 	expectedFilename := filepath.Join(builder.combustionDir, testFilename)
 	foundData, err := os.ReadFile(expectedFilename)
 	require.NoError(t, err)
+	assert.Equal(t, expectedFilename, writtenFilename)
 	assert.Equal(t, testData, string(foundData))
 
 	// Make sure the file isn't automatically added to the combustion scripts list
@@ -147,12 +148,13 @@ func TestWriteBuildDirFile(t *testing.T) {
 	testFilename := "build-dir-file.sh"
 
 	// Test
-	err = builder.writeBuildDirFile(testFilename, testData, nil)
+	writtenFilename, err := builder.writeBuildDirFile(testFilename, testData, nil)
 
 	// Verify
 	require.NoError(t, err)
 
 	expectedFilename := filepath.Join(builder.eibBuildDir, testFilename)
+	require.Equal(t, expectedFilename, writtenFilename)
 	foundData, err := os.ReadFile(expectedFilename)
 	require.NoError(t, err)
 	assert.Equal(t, testData, string(foundData))

pkg/build/message.go

@@ -13,7 +13,7 @@ const (
 var messageScript string
 
 func (b *Builder) configureMessage() error {
-	err := b.writeCombustionFile(messageScriptName, messageScript, nil)
+	_, err := b.writeCombustionFile(messageScriptName, messageScript, nil)
 	if err != nil {
 		return fmt.Errorf("copying script %s: %w", messageScriptName, err)
 	}

pkg/build/raw.go

@@ -3,13 +3,15 @@ package build
 import (
 	_ "embed"
 	"fmt"
+	"os"
 	"os/exec"
 	"path/filepath"
 )
 
 const (
 	copyExec         = "/bin/cp"
 	modifyScriptName = "modify-raw-image.sh"
+	modifyScriptMode = 0o744
 )
 
 //go:embed scripts/modify-raw-image.sh.tpl
@@ -54,10 +56,14 @@ func (b *Builder) writeModifyScript() error {
 		CombustionDir: b.combustionDir,
 	}
 
-	err := b.writeBuildDirFile(modifyScriptName, modifyRawImageScript, &values)
+	writtenFilename, err := b.writeBuildDirFile(modifyScriptName, modifyRawImageScript, &values)
 	if err != nil {
 		return fmt.Errorf("writing modification script %s: %w", modifyScriptName, err)
 	}
+	err = os.Chmod(writtenFilename, modifyScriptMode)
+	if err != nil {
+		return fmt.Errorf("changing permissions on the modification script %s: %w", modifyScriptName, err)
+	}
 
 	return nil
 }

pkg/build/raw_test.go

@@ -1,6 +1,7 @@
 package build
 
 import (
+	"io/fs"
 	"os"
 	"path/filepath"
 	"testing"
@@ -66,6 +67,10 @@ func TestWriteModifyScript(t *testing.T) {
 	foundBytes, err := os.ReadFile(expectedFilename)
 	require.NoError(t, err)
 
+	stats, err := os.Stat(expectedFilename)
+	require.NoError(t, err)
+	assert.Equal(t, fs.FileMode(modifyScriptMode), stats.Mode())
+
 	foundContents := string(foundBytes)
 	assert.Contains(t, foundContents, "guestfish --rw -a config-dir/output-image")
 	assert.Contains(t, foundContents, "copy-in "+builder.combustionDir)