debugd: Allow root login on serial console when using debug image (#407)

debugd/internal/debugd/deploy/seriallogin.go

@@ -0,0 +1,18 @@
+package deploy
+
+import (
+	"context"
+	"fmt"
+	"os/exec"
+)
+
+// DeleteUserPassword sets the user's password to an empty string
+// effectively allowing anyone with access to the serial console to log in.
+func DeleteUserPassword(ctx context.Context, user string) error {
+	cmd := exec.CommandContext(ctx, "passwd", "-d", user)
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		return fmt.Errorf("deleting user password: %q %w", output, err)
+	}
+	return nil
+}