diff --git a/tools/releasetools/common.py b/tools/releasetools/common.py
index b27e4c1..071277c 100644
--- a/tools/releasetools/common.py
+++ b/tools/releasetools/common.py
@@ -354,9 +354,12 @@
   else:
     print "building image from target_files %s..." % (tree_subdir,)
     fs_config = "META/" + tree_subdir.lower() + "_filesystem_config.txt"
-    return File(name, BuildBootableImage(os.path.join(unpack_dir, tree_subdir),
-                                         os.path.join(unpack_dir, fs_config),
-                                         info_dict))
+    data = BuildBootableImage(os.path.join(unpack_dir, tree_subdir),
+                              os.path.join(unpack_dir, fs_config),
+                              info_dict))
+    if data:
+      return File(name, data)
+    return None
 
 
 def UnzipTemp(filename, pattern=None):
diff --git a/tools/releasetools/make_recovery_patch b/tools/releasetools/make_recovery_patch
index 765063a..470dfc4 100755
--- a/tools/releasetools/make_recovery_patch
+++ b/tools/releasetools/make_recovery_patch
@@ -39,6 +39,9 @@
   boot_img = common.GetBootableImage("boot.img", "boot.img",
                                      input_dir, "BOOT")
 
+  if not recovery_img or not boot_img:
+    sys.exit(0)
+
   def output_sink(fn, data):
     with open(os.path.join(output_dir, "SYSTEM", *fn.split("/")), "wb") as f:
       f.write(data)