build_kernel_image.sh: set default verity_depth to 0

build_kernel_image.sh

 #!/bin/bash
 
 # Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # Helper script that generates the signed kernel image
 
 # --- BEGIN COMMON.SH BOILERPLATE ---
 # Load common CrOS utilities.  Inside the chroot this file is installed in
@@ skipping 46 matching lines @@
 DEFINE_string root "/dev/sd%D%P" \
   "Expected device root partition"
 # If provided, will automatically add verified boot arguments.
 DEFINE_string rootfs_image "" \
   "Optional path to the rootfs device or image.(Default: \"\")"
 DEFINE_string rootfs_hash "" \
   "Optional path to output the rootfs hash to. (Default: \"\")"
 DEFINE_integer verity_error_behavior 2 \
   "Verified boot error behavior [0: I/O errors, 1: reboot, 2: nothing] \
 (Default: 2)"
-DEFINE_integer verity_tree_depth 1 \
-  "Optional Verified boot hash tree depth. (Default: 1)"
+DEFINE_integer verity_tree_depth 0 \
+  "Optional Verified boot hash tree depth. (Default: 0)"
 DEFINE_integer verity_max_ios -1 \
   "Optional number of outstanding I/O operations. (Default: -1)"
 DEFINE_string verity_hash_alg "sha1" \
   "Cryptographic hash algorithm used for dm-verity. (Default: sha1)"
 
 # TODO(clchiou): Remove this flag after arm verified boot is stable
 DEFINE_boolean crosbug12352_arm_kernel_signing ${FLAGS_FALSE} \
   "Sign kernel partition for ARM images (temporary hack)."
 
 # Parse flags
@@ skipping 215 matching lines @@
   info "Cleaning up temporary files: ${WORK}"
   rm ${WORK}
   rmdir ${FLAGS_working_dir}
 fi
 
 info "Kernel partition image emitted: ${FLAGS_to}"
 
 if [[ -f ${FLAGS_rootfs_hash} ]]; then
   info "Root filesystem hash emitted: ${FLAGS_rootfs_hash}"
 fi