diff options
| -rw-r--r-- | pkg/sentry/fs/ext4/disklayout/BUILD | 11 | ||||
| -rw-r--r-- | pkg/sentry/fs/ext4/disklayout/block_group_test.go | 16 | ||||
| -rw-r--r-- | pkg/sentry/fs/ext4/disklayout/superblock_32.go | 76 | ||||
| -rw-r--r-- | pkg/sentry/fs/ext4/disklayout/superblock_64.go | 94 | ||||
| -rw-r--r-- | pkg/sentry/fs/ext4/disklayout/superblock_old.go | 108 | ||||
| -rw-r--r-- | pkg/sentry/fs/ext4/disklayout/superblock_test.go | 27 | ||||
| -rw-r--r-- | pkg/sentry/fs/ext4/disklayout/test_utils.go | 30 |
7 files changed, 348 insertions, 14 deletions
diff --git a/pkg/sentry/fs/ext4/disklayout/BUILD b/pkg/sentry/fs/ext4/disklayout/BUILD index be637bcbb..cdac63655 100644 --- a/pkg/sentry/fs/ext4/disklayout/BUILD +++ b/pkg/sentry/fs/ext4/disklayout/BUILD @@ -9,14 +9,21 @@ go_library( "block_group_32.go", "block_group_64.go", "superblock.go", + "superblock_32.go", + "superblock_64.go", + "superblock_old.go", + "test_utils.go", ], importpath = "gvisor.dev/gvisor/pkg/sentry/fs/ext4/disklayout", + deps = ["//pkg/binary"], ) go_test( name = "disklayout_test", size = "small", - srcs = ["block_group_test.go"], + srcs = [ + "block_group_test.go", + "superblock_test.go", + ], embed = [":disklayout"], - deps = ["//pkg/binary"], ) diff --git a/pkg/sentry/fs/ext4/disklayout/block_group_test.go b/pkg/sentry/fs/ext4/disklayout/block_group_test.go index 794ae99cc..0ef4294c0 100644 --- a/pkg/sentry/fs/ext4/disklayout/block_group_test.go +++ b/pkg/sentry/fs/ext4/disklayout/block_group_test.go @@ -16,19 +16,11 @@ package disklayout import ( "testing" - - "gvisor.dev/gvisor/pkg/binary" ) -// TestBlockGroupSize tests the fact that the block group struct for -// 32-bit ext filesystems should be exactly 32 bytes big and for 64-bit fs it -// should be 64 bytes. +// TestBlockGroupSize tests that the block group descriptor structs are of the +// correct size. func TestBlockGroupSize(t *testing.T) { - if got, want := int(binary.Size(BlockGroup32Bit{})), 32; got != want { - t.Errorf("BlockGroup32Bit should be exactly 32 bytes but is %d bytes", got) - } - - if got, want := int(binary.Size(BlockGroup64Bit{})), 64; got != want { - t.Errorf("BlockGroup64Bit should be exactly 64 bytes but is %d bytes", got) - } + assertSize(t, BlockGroup32Bit{}, 32) + assertSize(t, BlockGroup64Bit{}, 64) } diff --git a/pkg/sentry/fs/ext4/disklayout/superblock_32.go b/pkg/sentry/fs/ext4/disklayout/superblock_32.go new file mode 100644 index 000000000..4c3233eed --- /dev/null +++ b/pkg/sentry/fs/ext4/disklayout/superblock_32.go @@ -0,0 +1,76 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package disklayout + +// SuperBlock32Bit implements SuperBlock and represents the 32-bit version of +// the ext4_super_block struct in fs/ext4/ext4.h. +// +// The suffix `Raw` has been added to indicate that the field does not have a +// counterpart in the 64-bit version and to resolve name collision with the +// interface. +type SuperBlock32Bit struct { + // We embed the old superblock struct here because the 32-bit version is just + // an extension of the old version. + SuperBlockOld + + FirstInode uint32 + InodeSizeRaw uint16 + BlockGroupNumber uint16 + FeatureCompat uint32 + FeatureIncompat uint32 + FeatureRoCompat uint32 + UUID [16]byte + VolumeName [16]byte + LastMounted [64]byte + AlgoUsageBitmap uint32 + PreallocBlocks uint8 + PreallocDirBlocks uint8 + ReservedGdtBlocks uint16 + JournalUUID [16]byte + JournalInum uint32 + JournalDev uint32 + LastOrphan uint32 + HashSeed [4]uint32 + DefaultHashVersion uint8 + JnlBackupType uint8 + BgDescSizeRaw uint16 + DefaultMountOpts uint32 + FirstMetaBg uint32 + MkfsTime uint32 + JnlBlocks [17]uint32 +} + +// Only override methods which change based on the additional fields above. +// Not overriding SuperBlock.BgDescSize because it would still return 32 here. + +// InodeSize implements SuperBlock.InodeSize. +func (sb *SuperBlock32Bit) InodeSize() uint16 { + return sb.InodeSizeRaw +} + +// CompatibleFeatures implements SuperBlock.CompatibleFeatures. +func (sb *SuperBlock32Bit) CompatibleFeatures() CompatFeatures { + return CompatFeaturesFromInt(sb.FeatureCompat) +} + +// IncompatibleFeatures implements SuperBlock.IncompatibleFeatures. +func (sb *SuperBlock32Bit) IncompatibleFeatures() IncompatFeatures { + return IncompatFeaturesFromInt(sb.FeatureIncompat) +} + +// ReadOnlyCompatibleFeatures implements SuperBlock.ReadOnlyCompatibleFeatures. +func (sb *SuperBlock32Bit) ReadOnlyCompatibleFeatures() RoCompatFeatures { + return RoCompatFeaturesFromInt(sb.FeatureRoCompat) +} diff --git a/pkg/sentry/fs/ext4/disklayout/superblock_64.go b/pkg/sentry/fs/ext4/disklayout/superblock_64.go new file mode 100644 index 000000000..2e945a7c7 --- /dev/null +++ b/pkg/sentry/fs/ext4/disklayout/superblock_64.go @@ -0,0 +1,94 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package disklayout + +// SuperBlock64Bit implements SuperBlock and represents the 64-bit version of +// the ext4_super_block struct in fs/ext4/ext4.h. This sums up to be exactly +// 1024 bytes (smallest possible block size) and hence the superblock always +// fits in no more than one data block. +// +// The suffix `Hi` here stands for upper bits because they represent the upper +// half of the fields. +type SuperBlock64Bit struct { + // We embed the 32-bit struct here because 64-bit version is just an extension + // of the 32-bit version. + SuperBlock32Bit + + BlocksCountHi uint32 + ReservedBlocksCountHi uint32 + FreeBlocksCountHi uint32 + MinInodeSize uint16 + WantInodeSize uint16 + Flags uint32 + RaidStride uint16 + MmpInterval uint16 + MmpBlock uint64 + RaidStripeWidth uint32 + LogGroupsPerFlex uint8 + ChecksumType uint8 + _ uint16 + KbytesWritten uint64 + SnapshotInum uint32 + SnapshotID uint32 + SnapshotRsrvBlocksCount uint64 + SnapshotList uint32 + ErrorCount uint32 + FirstErrorTime uint32 + FirstErrorInode uint32 + FirstErrorBlock uint64 + FirstErrorFunction [32]byte + FirstErrorLine uint32 + LastErrorTime uint32 + LastErrorInode uint32 + LastErrorLine uint32 + LastErrorBlock uint64 + LastErrorFunction [32]byte + MountOpts [64]byte + UserQuotaInum uint32 + GroupQuotaInum uint32 + OverheadBlocks uint32 + BackupBgs [2]uint32 + EncryptAlgos [4]uint8 + EncryptPwSalt [16]uint8 + LostFoundInode uint32 + ProjectQuotaInode uint32 + ChecksumSeed uint32 + WtimeHi uint8 + MtimeHi uint8 + MkfsTimeHi uint8 + LastCheckHi uint8 + FirstErrorTimeHi uint8 + LastErrorTimeHi uint8 + _ [2]uint8 + Encoding uint16 + EncodingFlags uint16 + _ [95]uint32 + Checksum uint32 +} + +// Only override methods which change based on the 64-bit feature. + +// BlocksCount implements SuperBlock.BlocksCount. +func (sb *SuperBlock64Bit) BlocksCount() uint64 { + return (uint64(sb.BlocksCountHi) << 32) | uint64(sb.BlocksCountLo) +} + +// FreeBlocksCount implements SuperBlock.FreeBlocksCount. +func (sb *SuperBlock64Bit) FreeBlocksCount() uint64 { + return (uint64(sb.FreeBlocksCountHi) << 32) | uint64(sb.FreeBlocksCountLo) +} + +// BgDescSize implements SuperBlock.BgDescSize. +func (sb *SuperBlock64Bit) BgDescSize() uint16 { return sb.BgDescSizeRaw } diff --git a/pkg/sentry/fs/ext4/disklayout/superblock_old.go b/pkg/sentry/fs/ext4/disklayout/superblock_old.go new file mode 100644 index 000000000..1f7425ba3 --- /dev/null +++ b/pkg/sentry/fs/ext4/disklayout/superblock_old.go @@ -0,0 +1,108 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package disklayout + +// SuperBlockOld implements SuperBlock and represents the old version of the +// superblock struct in ext2 and ext3 systems. +// +// The suffix `Lo` here stands for lower bits because this is also used in the +// 64-bit version where these fields represent the lower half of the fields. +// The suffix `Raw` has been added to indicate that the field does not have a +// counterpart in the 64-bit version and to resolve name collision with the +// interface. +type SuperBlockOld struct { + InodesCountRaw uint32 + BlocksCountLo uint32 + ReservedBlocksCount uint32 + FreeBlocksCountLo uint32 + FreeInodesCountRaw uint32 + FirstDataBlockRaw uint32 + LogBlockSize uint32 + LogClusterSize uint32 + BlocksPerGroupRaw uint32 + ClustersPerGroupRaw uint32 + InodesPerGroupRaw uint32 + Mtime uint32 + Wtime uint32 + MountCountRaw uint16 + MaxMountCountRaw uint16 + MagicRaw uint16 + State uint16 + Errors uint16 + MinorRevLevel uint16 + LastCheck uint32 + CheckInterval uint32 + CreatorOS uint32 + RevLevel uint32 + DefResUID uint16 + DefResGID uint16 +} + +// InodesCount implements SuperBlock.InodesCount. +func (sb *SuperBlockOld) InodesCount() uint32 { return sb.InodesCountRaw } + +// BlocksCount implements SuperBlock.BlocksCount. +func (sb *SuperBlockOld) BlocksCount() uint64 { return uint64(sb.BlocksCountLo) } + +// FreeBlocksCount implements SuperBlock.FreeBlocksCount. +func (sb *SuperBlockOld) FreeBlocksCount() uint64 { return uint64(sb.FreeBlocksCountLo) } + +// FreeInodesCount implements SuperBlock.FreeInodesCount. +func (sb *SuperBlockOld) FreeInodesCount() uint32 { return sb.FreeInodesCountRaw } + +// MountCount implements SuperBlock.MountCount. +func (sb *SuperBlockOld) MountCount() uint16 { return sb.MountCountRaw } + +// MaxMountCount implements SuperBlock.MaxMountCount. +func (sb *SuperBlockOld) MaxMountCount() uint16 { return sb.MaxMountCountRaw } + +// FirstDataBlock implements SuperBlock.FirstDataBlock. +func (sb *SuperBlockOld) FirstDataBlock() uint32 { return sb.FirstDataBlockRaw } + +// BlockSize implements SuperBlock.BlockSize. +func (sb *SuperBlockOld) BlockSize() uint64 { return 1 << (10 + sb.LogBlockSize) } + +// BlocksPerGroup implements SuperBlock.BlocksPerGroup. +func (sb *SuperBlockOld) BlocksPerGroup() uint32 { return sb.BlocksPerGroupRaw } + +// ClusterSize implements SuperBlock.ClusterSize. +func (sb *SuperBlockOld) ClusterSize() uint64 { return 1 << (10 + sb.LogClusterSize) } + +// ClustersPerGroup implements SuperBlock.ClustersPerGroup. +func (sb *SuperBlockOld) ClustersPerGroup() uint32 { return sb.ClustersPerGroupRaw } + +// InodeSize implements SuperBlock.InodeSize. +func (sb *SuperBlockOld) InodeSize() uint16 { return 128 } + +// InodesPerGroup implements SuperBlock.InodesPerGroup. +func (sb *SuperBlockOld) InodesPerGroup() uint32 { return sb.InodesPerGroupRaw } + +// BgDescSize implements SuperBlock.BgDescSize. +func (sb *SuperBlockOld) BgDescSize() uint16 { return 32 } + +// CompatibleFeatures implements SuperBlock.CompatibleFeatures. +func (sb *SuperBlockOld) CompatibleFeatures() CompatFeatures { return CompatFeatures{} } + +// IncompatibleFeatures implements SuperBlock.IncompatibleFeatures. +func (sb *SuperBlockOld) IncompatibleFeatures() IncompatFeatures { return IncompatFeatures{} } + +// ReadOnlyCompatibleFeatures implements SuperBlock.ReadOnlyCompatibleFeatures. +func (sb *SuperBlockOld) ReadOnlyCompatibleFeatures() RoCompatFeatures { return RoCompatFeatures{} } + +// Magic implements SuperBlock.Magic. +func (sb *SuperBlockOld) Magic() uint16 { return sb.MagicRaw } + +// Revision implements SuperBlock.Revision. +func (sb *SuperBlockOld) Revision() SbRevision { return SbRevision(sb.RevLevel) } diff --git a/pkg/sentry/fs/ext4/disklayout/superblock_test.go b/pkg/sentry/fs/ext4/disklayout/superblock_test.go new file mode 100644 index 000000000..463b5ba21 --- /dev/null +++ b/pkg/sentry/fs/ext4/disklayout/superblock_test.go @@ -0,0 +1,27 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package disklayout + +import ( + "testing" +) + +// TestSuperBlockSize tests that the superblock structs are of the correct +// size. +func TestSuperBlockSize(t *testing.T) { + assertSize(t, SuperBlockOld{}, 84) + assertSize(t, SuperBlock32Bit{}, 336) + assertSize(t, SuperBlock64Bit{}, 1024) +} diff --git a/pkg/sentry/fs/ext4/disklayout/test_utils.go b/pkg/sentry/fs/ext4/disklayout/test_utils.go new file mode 100644 index 000000000..9c63f04c0 --- /dev/null +++ b/pkg/sentry/fs/ext4/disklayout/test_utils.go @@ -0,0 +1,30 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package disklayout + +import ( + "reflect" + "testing" + + "gvisor.dev/gvisor/pkg/binary" +) + +func assertSize(t *testing.T, v interface{}, want uintptr) { + t.Helper() + + if got := binary.Size(v); got != want { + t.Errorf("struct %s should be exactly %d bytes but is %d bytes", reflect.TypeOf(v).Name(), want, got) + } +} |