Merge remote-tracking branch 'aosp/upstream-master' into merge

It's a merge from chrome OS with some reverts.
1. the fd watcher change, because the libbrillo version isn't
compatible in aosp.
commit 6955bcc4ffe4cc9d62a88186b9a7e75d095a7897
commit 493fecb3f48c8478fd3ef244d631d857730dd14d
2. two libcurl unittest. Because the RunOnce() of the fake message
loop seems to have different behavior in aosp.
commit d3d84218cafbc1a95e7d6bbb775b495d1bebf4d2

Put preprocessor guards to use the old code in aosp. And we can
switch to the new code in the other path after adopting the new
libbrillo & libchrome.

Test: unit tests pass, apply an OTA
Change-Id: Id613599834b0f44f92841dbeae6303601db5490d

1 files changed, 77 insertions, 233 deletions

diff --git a/scripts/update_payload/checker.py b/scripts/update_payload/checker.py
index 6d17fbe5..4c655160 100644
--- a/scripts/update_payload/checker.py
+++ b/scripts/update_payload/checker.py
@@ -24,6 +24,7 @@ follows:
   checker.Run(...)
 """
 
+from __future__ import absolute_import
 from __future__ import print_function
 
 import array
@@ -34,22 +35,21 @@ import itertools
 import os
 import subprocess
 
+from six.moves import range
+
 from update_payload import common
 from update_payload import error
 from update_payload import format_utils
 from update_payload import histogram
 from update_payload import update_metadata_pb2
 
-
 #
 # Constants.
 #
 
-_CHECK_DST_PSEUDO_EXTENTS = 'dst-pseudo-extents'
 _CHECK_MOVE_SAME_SRC_DST_BLOCK = 'move-same-src-dst-block'
 _CHECK_PAYLOAD_SIG = 'payload-sig'
 CHECKS_TO_DISABLE = (
-    _CHECK_DST_PSEUDO_EXTENTS,
     _CHECK_MOVE_SAME_SRC_DST_BLOCK,
     _CHECK_PAYLOAD_SIG,
 )
@@ -66,7 +66,6 @@ _DEFAULT_PUBKEY_FILE_NAME = os.path.join(os.path.dirname(__file__),
 # Supported minor version map to payload types allowed to be using them.
 _SUPPORTED_MINOR_VERSIONS = {
     0: (_TYPE_FULL,),
-    1: (_TYPE_DELTA,),
     2: (_TYPE_DELTA,),
     3: (_TYPE_DELTA,),
     4: (_TYPE_DELTA,),
@@ -74,7 +73,6 @@ _SUPPORTED_MINOR_VERSIONS = {
     6: (_TYPE_DELTA,),
 }
 
-_OLD_DELTA_USABLE_PART_SIZE = 2 * 1024 * 1024 * 1024
 
 #
 # Helper functions.
@@ -323,8 +321,6 @@ class PayloadChecker(object):
     self.allow_unhashed = allow_unhashed
 
     # Disable specific tests.
-    self.check_dst_pseudo_extents = (
-        _CHECK_DST_PSEUDO_EXTENTS not in disabled_tests)
     self.check_move_same_src_dst_block = (
         _CHECK_MOVE_SAME_SRC_DST_BLOCK not in disabled_tests)
     self.check_payload_sig = _CHECK_PAYLOAD_SIG not in disabled_tests
@@ -609,7 +605,7 @@ class PayloadChecker(object):
     """
     self.major_version = self.payload.header.version
 
-    part_sizes = collections.defaultdict(int, part_sizes)
+    part_sizes = part_sizes or collections.defaultdict(int)
     manifest = self.payload.manifest
     report.AddSection('manifest')
 
@@ -628,35 +624,23 @@ class PayloadChecker(object):
     self._CheckPresentIff(self.sigs_offset, self.sigs_size,
                           'signatures_offset', 'signatures_size', 'manifest')
 
-    if self.major_version == common.CHROMEOS_MAJOR_PAYLOAD_VERSION:
-      for real_name, proto_name in common.CROS_PARTITIONS:
-        self.old_part_info[real_name] = self._CheckOptionalSubMsg(
-            manifest, 'old_%s_info' % proto_name, report)
-        self.new_part_info[real_name] = self._CheckMandatorySubMsg(
-            manifest, 'new_%s_info' % proto_name, report, 'manifest')
-
-      # Check: old_kernel_info <==> old_rootfs_info.
-      self._CheckPresentIff(self.old_part_info[common.KERNEL].msg,
-                            self.old_part_info[common.ROOTFS].msg,
-                            'old_kernel_info', 'old_rootfs_info', 'manifest')
-    else:
-      for part in manifest.partitions:
-        name = part.partition_name
-        self.old_part_info[name] = self._CheckOptionalSubMsg(
-            part, 'old_partition_info', report)
-        self.new_part_info[name] = self._CheckMandatorySubMsg(
-            part, 'new_partition_info', report, 'manifest.partitions')
-
-      # Check: Old-style partition infos should not be specified.
-      for _, part in common.CROS_PARTITIONS:
-        self._CheckElemNotPresent(manifest, 'old_%s_info' % part, 'manifest')
-        self._CheckElemNotPresent(manifest, 'new_%s_info' % part, 'manifest')
-
-      # Check: If old_partition_info is specified anywhere, it must be
-      # specified everywhere.
-      old_part_msgs = [part.msg for part in self.old_part_info.values() if part]
-      self._CheckPresentIffMany(old_part_msgs, 'old_partition_info',
-                                'manifest.partitions')
+    for part in manifest.partitions:
+      name = part.partition_name
+      self.old_part_info[name] = self._CheckOptionalSubMsg(
+          part, 'old_partition_info', report)
+      self.new_part_info[name] = self._CheckMandatorySubMsg(
+          part, 'new_partition_info', report, 'manifest.partitions')
+
+    # Check: Old-style partition infos should not be specified.
+    for _, part in common.CROS_PARTITIONS:
+      self._CheckElemNotPresent(manifest, 'old_%s_info' % part, 'manifest')
+      self._CheckElemNotPresent(manifest, 'new_%s_info' % part, 'manifest')
+
+    # Check: If old_partition_info is specified anywhere, it must be
+    # specified everywhere.
+    old_part_msgs = [part.msg for part in self.old_part_info.values() if part]
+    self._CheckPresentIffMany(old_part_msgs, 'old_partition_info',
+                              'manifest.partitions')
 
     is_delta = any(part and part.msg for part in self.old_part_info.values())
     if is_delta:
@@ -666,7 +650,7 @@ class PayloadChecker(object):
             'Apparent full payload contains old_{kernel,rootfs}_info.')
       self.payload_type = _TYPE_DELTA
 
-      for part, (msg, part_report) in self.old_part_info.iteritems():
+      for part, (msg, part_report) in self.old_part_info.items():
         # Check: {size, hash} present in old_{kernel,rootfs}_info.
         field = 'old_%s_info' % part
         self.old_fs_sizes[part] = self._CheckMandatoryField(msg, 'size',
@@ -687,7 +671,7 @@ class PayloadChecker(object):
       self.payload_type = _TYPE_FULL
 
     # Check: new_{kernel,rootfs}_info present; contains {size, hash}.
-    for part, (msg, part_report) in self.new_part_info.iteritems():
+    for part, (msg, part_report) in self.new_part_info.items():
       field = 'new_%s_info' % part
       self.new_fs_sizes[part] = self._CheckMandatoryField(msg, 'size',
                                                           part_report, field)
@@ -724,8 +708,7 @@ class PayloadChecker(object):
     self._CheckBlocksFitLength(length, total_blocks, self.block_size,
                                '%s: %s' % (op_name, length_name))
 
-  def _CheckExtents(self, extents, usable_size, block_counters, name,
-                    allow_pseudo=False, allow_signature=False):
+  def _CheckExtents(self, extents, usable_size, block_counters, name):
     """Checks a sequence of extents.
 
     Args:
@@ -733,8 +716,6 @@ class PayloadChecker(object):
       usable_size: The usable size of the partition to which the extents apply.
       block_counters: Array of counters corresponding to the number of blocks.
       name: The name of the extent block.
-      allow_pseudo: Whether or not pseudo block numbers are allowed.
-      allow_signature: Whether or not the extents are used for a signature.
 
     Returns:
       The total number of blocks in the extents.
@@ -755,20 +736,15 @@ class PayloadChecker(object):
       if num_blocks == 0:
         raise error.PayloadError('%s: extent length is zero.' % ex_name)
 
-      if start_block != common.PSEUDO_EXTENT_MARKER:
-        # Check: Make sure we're within the partition limit.
-        if usable_size and end_block * self.block_size > usable_size:
-          raise error.PayloadError(
-              '%s: extent (%s) exceeds usable partition size (%d).' %
-              (ex_name, common.FormatExtent(ex, self.block_size), usable_size))
+      # Check: Make sure we're within the partition limit.
+      if usable_size and end_block * self.block_size > usable_size:
+        raise error.PayloadError(
+            '%s: extent (%s) exceeds usable partition size (%d).' %
+            (ex_name, common.FormatExtent(ex, self.block_size), usable_size))
 
-        # Record block usage.
-        for i in xrange(start_block, end_block):
-          block_counters[i] += 1
-      elif not (allow_pseudo or (allow_signature and len(extents) == 1)):
-        # Pseudo-extents must be allowed explicitly, or otherwise be part of a
-        # signature operation (in which case there has to be exactly one).
-        raise error.PayloadError('%s: unexpected pseudo-extent.' % ex_name)
+      # Record block usage.
+      for i in range(start_block, end_block):
+        block_counters[i] += 1
 
       total_num_blocks += num_blocks
 
@@ -786,6 +762,11 @@ class PayloadChecker(object):
     Raises:
       error.PayloadError if any check fails.
     """
+    # Check: total_dst_blocks is not a floating point.
+    if isinstance(total_dst_blocks, float):
+      raise error.PayloadError('%s: contains invalid data type of '
+                               'total_dst_blocks.' % op_name)
+
     # Check: Does not contain src extents.
     if op.src_extents:
       raise error.PayloadError('%s: contains src_extents.' % op_name)
@@ -806,89 +787,6 @@ class PayloadChecker(object):
             'space (%d * %d).' %
             (op_name, data_length, total_dst_blocks, self.block_size))
 
-  def _CheckMoveOperation(self, op, data_offset, total_src_blocks,
-                          total_dst_blocks, op_name):
-    """Specific checks for MOVE operations.
-
-    Args:
-      op: The operation object from the manifest.
-      data_offset: The offset of a data blob for the operation.
-      total_src_blocks: Total number of blocks in src_extents.
-      total_dst_blocks: Total number of blocks in dst_extents.
-      op_name: Operation name for error reporting.
-
-    Raises:
-      error.PayloadError if any check fails.
-    """
-    # Check: No data_{offset,length}.
-    if data_offset is not None:
-      raise error.PayloadError('%s: contains data_{offset,length}.' % op_name)
-
-    # Check: total_src_blocks == total_dst_blocks.
-    if total_src_blocks != total_dst_blocks:
-      raise error.PayloadError(
-          '%s: total src blocks (%d) != total dst blocks (%d).' %
-          (op_name, total_src_blocks, total_dst_blocks))
-
-    # Check: For all i, i-th src block index != i-th dst block index.
-    i = 0
-    src_extent_iter = iter(op.src_extents)
-    dst_extent_iter = iter(op.dst_extents)
-    src_extent = dst_extent = None
-    src_idx = src_num = dst_idx = dst_num = 0
-    while i < total_src_blocks:
-      # Get the next source extent, if needed.
-      if not src_extent:
-        try:
-          src_extent = src_extent_iter.next()
-        except StopIteration:
-          raise error.PayloadError('%s: ran out of src extents (%d/%d).' %
-                                   (op_name, i, total_src_blocks))
-        src_idx = src_extent.start_block
-        src_num = src_extent.num_blocks
-
-      # Get the next dest extent, if needed.
-      if not dst_extent:
-        try:
-          dst_extent = dst_extent_iter.next()
-        except StopIteration:
-          raise error.PayloadError('%s: ran out of dst extents (%d/%d).' %
-                                   (op_name, i, total_dst_blocks))
-        dst_idx = dst_extent.start_block
-        dst_num = dst_extent.num_blocks
-
-      # Check: start block is not 0. See crbug/480751; there are still versions
-      # of update_engine which fail when seeking to 0 in PReadAll and PWriteAll,
-      # so we need to fail payloads that try to MOVE to/from block 0.
-      if src_idx == 0 or dst_idx == 0:
-        raise error.PayloadError(
-            '%s: MOVE operation cannot have extent with start block 0' %
-            op_name)
-
-      if self.check_move_same_src_dst_block and src_idx == dst_idx:
-        raise error.PayloadError(
-            '%s: src/dst block number %d is the same (%d).' %
-            (op_name, i, src_idx))
-
-      advance = min(src_num, dst_num)
-      i += advance
-
-      src_idx += advance
-      src_num -= advance
-      if src_num == 0:
-        src_extent = None
-
-      dst_idx += advance
-      dst_num -= advance
-      if dst_num == 0:
-        dst_extent = None
-
-    # Make sure we've exhausted all src/dst extents.
-    if src_extent:
-      raise error.PayloadError('%s: excess src blocks.' % op_name)
-    if dst_extent:
-      raise error.PayloadError('%s: excess dst blocks.' % op_name)
-
   def _CheckZeroOperation(self, op, op_name):
     """Specific checks for ZERO operations.
 
@@ -908,7 +806,7 @@ class PayloadChecker(object):
       raise error.PayloadError('%s: contains data_offset.' % op_name)
 
   def _CheckAnyDiffOperation(self, op, data_length, total_dst_blocks, op_name):
-    """Specific checks for BSDIFF, SOURCE_BSDIFF, PUFFDIFF and BROTLI_BSDIFF
+    """Specific checks for SOURCE_BSDIFF, PUFFDIFF and BROTLI_BSDIFF
        operations.
 
     Args:
@@ -933,8 +831,7 @@ class PayloadChecker(object):
            total_dst_blocks * self.block_size))
 
     # Check the existence of src_length and dst_length for legacy bsdiffs.
-    if (op.type == common.OpType.BSDIFF or
-        (op.type == common.OpType.SOURCE_BSDIFF and self.minor_version <= 3)):
+    if op.type == common.OpType.SOURCE_BSDIFF and self.minor_version <= 3:
       if not op.HasField('src_length') or not op.HasField('dst_length'):
         raise error.PayloadError('%s: require {src,dst}_length.' % op_name)
     else:
@@ -983,21 +880,19 @@ class PayloadChecker(object):
     if self.minor_version >= 3 and op.src_sha256_hash is None:
       raise error.PayloadError('%s: source hash missing.' % op_name)
 
-  def _CheckOperation(self, op, op_name, is_last, old_block_counters,
-                      new_block_counters, old_usable_size, new_usable_size,
-                      prev_data_offset, allow_signature, blob_hash_counts):
+  def _CheckOperation(self, op, op_name, old_block_counters, new_block_counters,
+                      old_usable_size, new_usable_size, prev_data_offset,
+                      blob_hash_counts):
     """Checks a single update operation.
 
     Args:
       op: The operation object.
       op_name: Operation name string for error reporting.
-      is_last: Whether this is the last operation in the sequence.
       old_block_counters: Arrays of block read counters.
       new_block_counters: Arrays of block write counters.
       old_usable_size: The overall usable size for src data in bytes.
       new_usable_size: The overall usable size for dst data in bytes.
       prev_data_offset: Offset of last used data bytes.
-      allow_signature: Whether this may be a signature operation.
       blob_hash_counts: Counters for hashed/unhashed blobs.
 
     Returns:
@@ -1009,14 +904,10 @@ class PayloadChecker(object):
     # Check extents.
     total_src_blocks = self._CheckExtents(
         op.src_extents, old_usable_size, old_block_counters,
-        op_name + '.src_extents', allow_pseudo=True)
-    allow_signature_in_extents = (allow_signature and is_last and
-                                  op.type == common.OpType.REPLACE)
+        op_name + '.src_extents')
     total_dst_blocks = self._CheckExtents(
         op.dst_extents, new_usable_size, new_block_counters,
-        op_name + '.dst_extents',
-        allow_pseudo=(not self.check_dst_pseudo_extents),
-        allow_signature=allow_signature_in_extents)
+        op_name + '.dst_extents')
 
     # Check: data_offset present <==> data_length present.
     data_offset = self._CheckOptionalField(op, 'data_offset', None)
@@ -1052,9 +943,7 @@ class PayloadChecker(object):
             (op_name, common.FormatSha256(op.data_sha256_hash),
              common.FormatSha256(actual_hash.digest())))
     elif data_offset is not None:
-      if allow_signature_in_extents:
-        blob_hash_counts['signature'] += 1
-      elif self.allow_unhashed:
+      if self.allow_unhashed:
         blob_hash_counts['unhashed'] += 1
       else:
         raise error.PayloadError('%s: unhashed operation not allowed.' %
@@ -1068,19 +957,11 @@ class PayloadChecker(object):
             (op_name, data_offset, prev_data_offset))
 
     # Type-specific checks.
-    if op.type in (common.OpType.REPLACE, common.OpType.REPLACE_BZ):
-      self._CheckReplaceOperation(op, data_length, total_dst_blocks, op_name)
-    elif (op.type == common.OpType.REPLACE_XZ and
-          (self.minor_version >= 3 or
-           self.major_version >= common.BRILLO_MAJOR_PAYLOAD_VERSION)):
+    if op.type in (common.OpType.REPLACE, common.OpType.REPLACE_BZ,
+                   common.OpType.REPLACE_XZ):
       self._CheckReplaceOperation(op, data_length, total_dst_blocks, op_name)
-    elif op.type == common.OpType.MOVE and self.minor_version == 1:
-      self._CheckMoveOperation(op, data_offset, total_src_blocks,
-                               total_dst_blocks, op_name)
     elif op.type == common.OpType.ZERO and self.minor_version >= 4:
       self._CheckZeroOperation(op, op_name)
-    elif op.type == common.OpType.BSDIFF and self.minor_version == 1:
-      self._CheckAnyDiffOperation(op, data_length, total_dst_blocks, op_name)
     elif op.type == common.OpType.SOURCE_COPY and self.minor_version >= 2:
       self._CheckSourceCopyOperation(data_offset, total_src_blocks,
                                      total_dst_blocks, op_name)
@@ -1102,7 +983,7 @@ class PayloadChecker(object):
 
   def _SizeToNumBlocks(self, size):
     """Returns the number of blocks needed to contain a given byte size."""
-    return (size + self.block_size - 1) / self.block_size
+    return (size + self.block_size - 1) // self.block_size
 
   def _AllocBlockCounters(self, total_size):
     """Returns a freshly initialized array of block counters.
@@ -1122,7 +1003,7 @@ class PayloadChecker(object):
 
   def _CheckOperations(self, operations, report, base_name, old_fs_size,
                        new_fs_size, old_usable_size, new_usable_size,
-                       prev_data_offset, allow_signature):
+                       prev_data_offset):
     """Checks a sequence of update operations.
 
     Args:
@@ -1134,7 +1015,6 @@ class PayloadChecker(object):
       old_usable_size: The overall usable size of the old partition in bytes.
       new_usable_size: The overall usable size of the new partition in bytes.
       prev_data_offset: Offset of last used data bytes.
-      allow_signature: Whether this sequence may contain signature operations.
 
     Returns:
       The total data blob size used.
@@ -1149,9 +1029,7 @@ class PayloadChecker(object):
         common.OpType.REPLACE: 0,
         common.OpType.REPLACE_BZ: 0,
         common.OpType.REPLACE_XZ: 0,
-        common.OpType.MOVE: 0,
         common.OpType.ZERO: 0,
-        common.OpType.BSDIFF: 0,
         common.OpType.SOURCE_COPY: 0,
         common.OpType.SOURCE_BSDIFF: 0,
         common.OpType.PUFFDIFF: 0,
@@ -1162,8 +1040,6 @@ class PayloadChecker(object):
         common.OpType.REPLACE: 0,
         common.OpType.REPLACE_BZ: 0,
         common.OpType.REPLACE_XZ: 0,
-        # MOVE operations don't have blobs.
-        common.OpType.BSDIFF: 0,
         # SOURCE_COPY operations don't have blobs.
         common.OpType.SOURCE_BSDIFF: 0,
         common.OpType.PUFFDIFF: 0,
@@ -1174,8 +1050,6 @@ class PayloadChecker(object):
         'hashed': 0,
         'unhashed': 0,
     }
-    if allow_signature:
-      blob_hash_counts['signature'] = 0
 
     # Allocate old and new block counters.
     old_block_counters = (self._AllocBlockCounters(old_usable_size)
@@ -1188,16 +1062,14 @@ class PayloadChecker(object):
       op_num += 1
 
       # Check: Type is valid.
-      if op.type not in op_counts.keys():
+      if op.type not in op_counts:
         raise error.PayloadError('%s: invalid type (%d).' % (op_name, op.type))
       op_counts[op.type] += 1
 
-      is_last = op_num == len(operations)
       curr_data_used = self._CheckOperation(
-          op, op_name, is_last, old_block_counters, new_block_counters,
+          op, op_name, old_block_counters, new_block_counters,
           old_usable_size, new_usable_size,
-          prev_data_offset + total_data_used, allow_signature,
-          blob_hash_counts)
+          prev_data_offset + total_data_used, blob_hash_counts)
       if curr_data_used:
         op_blob_totals[op.type] += curr_data_used
         total_data_used += curr_data_used
@@ -1251,21 +1123,17 @@ class PayloadChecker(object):
     if not sigs.signatures:
       raise error.PayloadError('Signature block is empty.')
 
-    last_ops_section = (self.payload.manifest.kernel_install_operations or
-                        self.payload.manifest.install_operations)
-
-    # Only major version 1 has the fake signature OP at the end.
-    if self.major_version == common.CHROMEOS_MAJOR_PAYLOAD_VERSION:
-      fake_sig_op = last_ops_section[-1]
+    # Check that we don't have the signature operation blob at the end (used to
+    # be for major version 1).
+    last_partition = self.payload.manifest.partitions[-1]
+    if last_partition.operations:
+      last_op = last_partition.operations[-1]
       # Check: signatures_{offset,size} must match the last (fake) operation.
-      if not (fake_sig_op.type == common.OpType.REPLACE and
-              self.sigs_offset == fake_sig_op.data_offset and
-              self.sigs_size == fake_sig_op.data_length):
-        raise error.PayloadError('Signatures_{offset,size} (%d+%d) does not'
-                                 ' match last operation (%d+%d).' %
-                                 (self.sigs_offset, self.sigs_size,
-                                  fake_sig_op.data_offset,
-                                  fake_sig_op.data_length))
+      if (last_op.type == common.OpType.REPLACE and
+          last_op.data_offset == self.sigs_offset and
+          last_op.data_length == self.sigs_size):
+        raise error.PayloadError('It seems like the last operation is the '
+                                 'signature blob. This is an invalid payload.')
 
     # Compute the checksum of all data up to signature blob.
     # TODO(garnold) we're re-reading the whole data section into a string
@@ -1344,62 +1212,38 @@ class PayloadChecker(object):
       self._CheckManifest(report, part_sizes)
       assert self.payload_type, 'payload type should be known by now'
 
-      manifest = self.payload.manifest
-
-      # Part 3: Examine partition operations.
-      install_operations = []
-      if self.major_version == common.CHROMEOS_MAJOR_PAYLOAD_VERSION:
-        # partitions field should not ever exist in major version 1 payloads
-        self._CheckRepeatedElemNotPresent(manifest, 'partitions', 'manifest')
-
-        install_operations.append((common.ROOTFS, manifest.install_operations))
-        install_operations.append((common.KERNEL,
-                                   manifest.kernel_install_operations))
-
-      else:
-        self._CheckRepeatedElemNotPresent(manifest, 'install_operations',
+      # Make sure deprecated values are not present in the payload.
+      for field in ('install_operations', 'kernel_install_operations'):
+        self._CheckRepeatedElemNotPresent(self.payload.manifest, field,
                                           'manifest')
-        self._CheckRepeatedElemNotPresent(manifest, 'kernel_install_operations',
-                                          'manifest')
-
-        for update in manifest.partitions:
-          install_operations.append((update.partition_name, update.operations))
+      for field in ('old_kernel_info', 'old_rootfs_info',
+                    'new_kernel_info', 'new_rootfs_info'):
+        self._CheckElemNotPresent(self.payload.manifest, field, 'manifest')
 
       total_blob_size = 0
-      for part, operations in install_operations:
+      for part, operations in ((p.partition_name, p.operations)
+                               for p in self.payload.manifest.partitions):
         report.AddSection('%s operations' % part)
 
         new_fs_usable_size = self.new_fs_sizes[part]
         old_fs_usable_size = self.old_fs_sizes[part]
 
-        if part_sizes.get(part, None):
+        if part_sizes is not None and part_sizes.get(part, None):
           new_fs_usable_size = old_fs_usable_size = part_sizes[part]
-        # Infer the usable partition size when validating rootfs operations:
-        # - If rootfs partition size was provided, use that.
-        # - Otherwise, if this is an older delta (minor version < 2), stick with
-        #   a known constant size. This is necessary because older deltas may
-        #   exceed the filesystem size when moving data blocks around.
-        # - Otherwise, use the encoded filesystem size.
-        elif self.payload_type == _TYPE_DELTA and part == common.ROOTFS and \
-            self.minor_version in (None, 1):
-          new_fs_usable_size = old_fs_usable_size = _OLD_DELTA_USABLE_PART_SIZE
-
-        # TODO(garnold)(chromium:243559) only default to the filesystem size if
-        # no explicit size provided *and* the partition size is not embedded in
-        # the payload; see issue for more details.
+
+        # TODO(chromium:243559) only default to the filesystem size if no
+        # explicit size provided *and* the partition size is not embedded in the
+        # payload; see issue for more details.
         total_blob_size += self._CheckOperations(
             operations, report, '%s_install_operations' % part,
             self.old_fs_sizes[part], self.new_fs_sizes[part],
-            old_fs_usable_size, new_fs_usable_size, total_blob_size,
-            (self.major_version == common.CHROMEOS_MAJOR_PAYLOAD_VERSION
-             and part == common.KERNEL))
+            old_fs_usable_size, new_fs_usable_size, total_blob_size)
 
       # Check: Operations data reach the end of the payload file.
       used_payload_size = self.payload.data_offset + total_blob_size
       # Major versions 2 and higher have a signature at the end, so it should be
       # considered in the total size of the image.
-      if (self.major_version >= common.BRILLO_MAJOR_PAYLOAD_VERSION and
-          self.sigs_size):
+      if self.sigs_size:
         used_payload_size += self.sigs_size
 
       if used_payload_size != payload_file_size: