diff --git a/tools/releasetools/add_img_to_target_files.py b/tools/releasetools/add_img_to_target_files.py
index 91213ba..1a08cb6 100755
--- a/tools/releasetools/add_img_to_target_files.py
+++ b/tools/releasetools/add_img_to_target_files.py
@@ -59,6 +59,7 @@
 import shutil
 import subprocess
 import tempfile
+import uuid
 import zipfile
 
 import build_image
@@ -258,6 +259,19 @@
   if block_list:
     image_props["block_list"] = block_list.name
 
+  # Use repeatable ext4 FS UUID and hash_seed UUID (based on partition name and
+  # build fingerprint).
+  uuid_seed = what + "-"
+  if "build.prop" in info_dict:
+    build_prop = info_dict["build.prop"]
+    if "ro.build.fingerprint" in build_prop:
+      uuid_seed += build_prop["ro.build.fingerprint"]
+    elif "ro.build.thumbprint" in build_prop:
+      uuid_seed += build_prop["ro.build.thumbprint"]
+  image_props["uuid"] = str(uuid.uuid5(uuid.NAMESPACE_URL, uuid_seed))
+  hash_seed = "hash_seed-" + uuid_seed
+  image_props["hash_seed"] = str(uuid.uuid5(uuid.NAMESPACE_URL, hash_seed))
+
   succ = build_image.BuildImage(os.path.join(temp_dir, what),
                                 image_props, output_file.name)
   assert succ, "build " + what + ".img image failed"
diff --git a/tools/releasetools/build_image.py b/tools/releasetools/build_image.py
index 94626d7..3f976da 100755
--- a/tools/releasetools/build_image.py
+++ b/tools/releasetools/build_image.py
@@ -478,6 +478,12 @@
       build_command.extend(["-e", prop_dict["flash_erase_block_size"]])
     if "flash_logical_block_size" in prop_dict:
       build_command.extend(["-o", prop_dict["flash_logical_block_size"]])
+    # Specify UUID and hash_seed if using mke2fs.
+    if prop_dict["ext_mkuserimg"] == "mkuserimg_mke2fs.sh":
+      if "uuid" in prop_dict:
+        build_command.extend(["-U", prop_dict["uuid"]])
+      if "hash_seed" in prop_dict:
+        build_command.extend(["-S", prop_dict["hash_seed"]])
     if "selinux_fc" in prop_dict:
       build_command.append(prop_dict["selinux_fc"])
   elif fs_type.startswith("squash"):