[go-marshal] Port ext codebase to use go marshal.

PiperOrigin-RevId: 334656292

22 files changed, 79 insertions, 20 deletions

diff --git a/pkg/sentry/fsimpl/ext/disklayout/BUILD b/pkg/sentry/fsimpl/ext/disklayout/BUILD
index 9bd9c76c0..d98a05dd8 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/BUILD
+++ b/pkg/sentry/fsimpl/ext/disklayout/BUILD
@@ -22,10 +22,11 @@ go_library(
         "superblock_old.go",
         "test_utils.go",
     ],
+    marshal = True,
     visibility = ["//pkg/sentry:internal"],
     deps = [
         "//pkg/abi/linux",
-        "//pkg/binary",
+        "//pkg/marshal",
         "//pkg/sentry/fs",
         "//pkg/sentry/kernel/auth",
         "//pkg/sentry/kernel/time",
diff --git a/pkg/sentry/fsimpl/ext/disklayout/block_group.go b/pkg/sentry/fsimpl/ext/disklayout/block_group.go
index ad6f4fef8..0d56ae9da 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/block_group.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/block_group.go
@@ -14,6 +14,10 @@
 
 package disklayout
 
+import (
+	"gvisor.dev/gvisor/pkg/marshal"
+)
+
 // BlockGroup represents a Linux ext block group descriptor. An ext file system
 // is split into a series of block groups. This provides an access layer to
 // information needed to access and use a block group.
@@ -30,6 +34,8 @@ package disklayout
 //
 // See https://www.kernel.org/doc/html/latest/filesystems/ext4/globals.html#block-group-descriptors.
 type BlockGroup interface {
+	marshal.Marshallable
+
 	// InodeTable returns the absolute block number of the block containing the
 	// inode table. This points to an array of Inode structs. Inode tables are
 	// statically allocated at mkfs time. The superblock records the number of
diff --git a/pkg/sentry/fsimpl/ext/disklayout/block_group_32.go b/pkg/sentry/fsimpl/ext/disklayout/block_group_32.go
index 3e16c76db..a35fa22a0 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/block_group_32.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/block_group_32.go
@@ -17,6 +17,8 @@ package disklayout
 // BlockGroup32Bit emulates the first half of struct ext4_group_desc in
 // fs/ext4/ext4.h. It is the block group descriptor struct for ext2, ext3 and
 // 32-bit ext4 filesystems. It implements BlockGroup interface.
+//
+// +marshal
 type BlockGroup32Bit struct {
 	BlockBitmapLo         uint32
 	InodeBitmapLo         uint32
diff --git a/pkg/sentry/fsimpl/ext/disklayout/block_group_64.go b/pkg/sentry/fsimpl/ext/disklayout/block_group_64.go
index 9a809197a..d54d1d345 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/block_group_64.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/block_group_64.go
@@ -18,6 +18,8 @@ package disklayout
 // It is the block group descriptor struct for 64-bit ext4 filesystems.
 // It implements BlockGroup interface. It is an extension of the 32-bit
 // version of BlockGroup.
+//
+// +marshal
 type BlockGroup64Bit struct {
 	// We embed the 32-bit struct here because 64-bit version is just an extension
 	// of the 32-bit version.
diff --git a/pkg/sentry/fsimpl/ext/disklayout/block_group_test.go b/pkg/sentry/fsimpl/ext/disklayout/block_group_test.go
index 0ef4294c0..e4ce484e4 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/block_group_test.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/block_group_test.go
@@ -21,6 +21,8 @@ import (
 // TestBlockGroupSize tests that the block group descriptor structs are of the
 // correct size.
 func TestBlockGroupSize(t *testing.T) {
-	assertSize(t, BlockGroup32Bit{}, 32)
-	assertSize(t, BlockGroup64Bit{}, 64)
+	var bgSmall BlockGroup32Bit
+	assertSize(t, &bgSmall, 32)
+	var bgBig BlockGroup64Bit
+	assertSize(t, &bgBig, 64)
 }
diff --git a/pkg/sentry/fsimpl/ext/disklayout/dirent.go b/pkg/sentry/fsimpl/ext/disklayout/dirent.go
index 417b6cf65..568c8cb4c 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/dirent.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/dirent.go
@@ -15,6 +15,7 @@
 package disklayout
 
 import (
+	"gvisor.dev/gvisor/pkg/marshal"
 	"gvisor.dev/gvisor/pkg/sentry/fs"
 )
 
@@ -51,6 +52,8 @@ var (
 //
 // See https://www.kernel.org/doc/html/latest/filesystems/ext4/dynamic.html#linear-classic-directories.
 type Dirent interface {
+	marshal.Marshallable
+
 	// Inode returns the absolute inode number of the underlying inode.
 	// Inode number 0 signifies an unused dirent.
 	Inode() uint32
diff --git a/pkg/sentry/fsimpl/ext/disklayout/dirent_new.go b/pkg/sentry/fsimpl/ext/disklayout/dirent_new.go
index 29ae4a5c2..51f9c2946 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/dirent_new.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/dirent_new.go
@@ -29,12 +29,14 @@ import (
 // Note: This struct can be of variable size on disk. The one described below
 // is of maximum size and the FileName beyond NameLength bytes might contain
 // garbage.
+//
+// +marshal
 type DirentNew struct {
 	InodeNumber  uint32
 	RecordLength uint16
 	NameLength   uint8
 	FileTypeRaw  uint8
-	FileNameRaw  [MaxFileName]byte
+	FileNameRaw  [MaxFileName]byte `marshal:"unaligned"`
 }
 
 // Compiles only if DirentNew implements Dirent.
diff --git a/pkg/sentry/fsimpl/ext/disklayout/dirent_old.go b/pkg/sentry/fsimpl/ext/disklayout/dirent_old.go
index 6fff12a6e..d4b19e086 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/dirent_old.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/dirent_old.go
@@ -22,11 +22,13 @@ import "gvisor.dev/gvisor/pkg/sentry/fs"
 // Note: This struct can be of variable size on disk. The one described below
 // is of maximum size and the FileName beyond NameLength bytes might contain
 // garbage.
+//
+// +marshal
 type DirentOld struct {
 	InodeNumber  uint32
 	RecordLength uint16
 	NameLength   uint16
-	FileNameRaw  [MaxFileName]byte
+	FileNameRaw  [MaxFileName]byte `marshal:"unaligned"`
 }
 
 // Compiles only if DirentOld implements Dirent.
diff --git a/pkg/sentry/fsimpl/ext/disklayout/dirent_test.go b/pkg/sentry/fsimpl/ext/disklayout/dirent_test.go
index 934919f8a..3486864dc 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/dirent_test.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/dirent_test.go
@@ -21,6 +21,8 @@ import (
 // TestDirentSize tests that the dirent structs are of the correct
 // size.
 func TestDirentSize(t *testing.T) {
-	assertSize(t, DirentOld{}, uintptr(DirentSize))
-	assertSize(t, DirentNew{}, uintptr(DirentSize))
+	var dOld DirentOld
+	assertSize(t, &dOld, DirentSize)
+	var dNew DirentNew
+	assertSize(t, &dNew, DirentSize)
 }
diff --git a/pkg/sentry/fsimpl/ext/disklayout/disklayout.go b/pkg/sentry/fsimpl/ext/disklayout/disklayout.go
index bdf4e2132..0834e9ba8 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/disklayout.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/disklayout.go
@@ -36,8 +36,6 @@
 //     escape analysis on an unknown implementation at compile time.
 //
 // Notes:
-//   - All fields in these structs are exported because binary.Read would
-//     panic otherwise.
 //   - All structures on disk are in little-endian order. Only jbd2 (journal)
 //     structures are in big-endian order.
 //   - All OS dependent fields in these structures will be interpretted using
diff --git a/pkg/sentry/fsimpl/ext/disklayout/extent.go b/pkg/sentry/fsimpl/ext/disklayout/extent.go
index 4110649ab..b13999bfc 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/extent.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/extent.go
@@ -14,6 +14,10 @@
 
 package disklayout
 
+import (
+	"gvisor.dev/gvisor/pkg/marshal"
+)
+
 // Extents were introduced in ext4 and provide huge performance gains in terms
 // data locality and reduced metadata block usage. Extents are organized in
 // extent trees. The root node is contained in inode.BlocksRaw.
@@ -64,6 +68,8 @@ type ExtentNode struct {
 // ExtentEntry represents an extent tree node entry. The entry can either be
 // an ExtentIdx or Extent itself. This exists to simplify navigation logic.
 type ExtentEntry interface {
+	marshal.Marshallable
+
 	// FileBlock returns the first file block number covered by this entry.
 	FileBlock() uint32
 
@@ -75,6 +81,8 @@ type ExtentEntry interface {
 // tree node begins with this and is followed by `NumEntries` number of:
 //   - Extent         if `Depth` == 0
 //   - ExtentIdx      otherwise
+//
+// +marshal
 type ExtentHeader struct {
 	// Magic in the extent magic number, must be 0xf30a.
 	Magic uint16
@@ -96,6 +104,8 @@ type ExtentHeader struct {
 // internal nodes. Sorted in ascending order based on FirstFileBlock since
 // Linux does a binary search on this. This points to a block containing the
 // child node.
+//
+// +marshal
 type ExtentIdx struct {
 	FirstFileBlock uint32
 	ChildBlockLo   uint32
@@ -121,6 +131,8 @@ func (ei *ExtentIdx) PhysicalBlock() uint64 {
 // nodes. Sorted in ascending order based on FirstFileBlock since Linux does a
 // binary search on this. This points to an array of data blocks containing the
 // file data. It covers `Length` data blocks starting from `StartBlock`.
+//
+// +marshal
 type Extent struct {
 	FirstFileBlock uint32
 	Length         uint16
diff --git a/pkg/sentry/fsimpl/ext/disklayout/extent_test.go b/pkg/sentry/fsimpl/ext/disklayout/extent_test.go
index 8762b90db..c96002e19 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/extent_test.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/extent_test.go
@@ -21,7 +21,10 @@ import (
 // TestExtentSize tests that the extent structs are of the correct
 // size.
 func TestExtentSize(t *testing.T) {
-	assertSize(t, ExtentHeader{}, ExtentHeaderSize)
-	assertSize(t, ExtentIdx{}, ExtentEntrySize)
-	assertSize(t, Extent{}, ExtentEntrySize)
+	var h ExtentHeader
+	assertSize(t, &h, ExtentHeaderSize)
+	var i ExtentIdx
+	assertSize(t, &i, ExtentEntrySize)
+	var e Extent
+	assertSize(t, &e, ExtentEntrySize)
 }
diff --git a/pkg/sentry/fsimpl/ext/disklayout/inode.go b/pkg/sentry/fsimpl/ext/disklayout/inode.go
index 88ae913f5..ef25040a9 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/inode.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/inode.go
@@ -16,6 +16,7 @@ package disklayout
 
 import (
 	"gvisor.dev/gvisor/pkg/abi/linux"
+	"gvisor.dev/gvisor/pkg/marshal"
 	"gvisor.dev/gvisor/pkg/sentry/kernel/auth"
 	"gvisor.dev/gvisor/pkg/sentry/kernel/time"
 )
@@ -38,6 +39,8 @@ const (
 //
 // See https://www.kernel.org/doc/html/latest/filesystems/ext4/dynamic.html#index-nodes.
 type Inode interface {
+	marshal.Marshallable
+
 	// Mode returns the linux file mode which is majorly used to extract
 	// information like:
 	// - File permissions (read/write/execute by user/group/others).
diff --git a/pkg/sentry/fsimpl/ext/disklayout/inode_new.go b/pkg/sentry/fsimpl/ext/disklayout/inode_new.go
index 8f9f574ce..a4503f5cf 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/inode_new.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/inode_new.go
@@ -27,6 +27,8 @@ import "gvisor.dev/gvisor/pkg/sentry/kernel/time"
 // are used to provide nanoscond precision. Hence, these timestamps will now
 // overflow in May 2446.
 // See https://www.kernel.org/doc/html/latest/filesystems/ext4/dynamic.html#inode-timestamps.
+//
+// +marshal
 type InodeNew struct {
 	InodeOld
 
diff --git a/pkg/sentry/fsimpl/ext/disklayout/inode_old.go b/pkg/sentry/fsimpl/ext/disklayout/inode_old.go
index db25b11b6..e6b28babf 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/inode_old.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/inode_old.go
@@ -30,6 +30,8 @@ const (
 //
 // All fields representing time are in seconds since the epoch. Which means that
 // they will overflow in January 2038.
+//
+// +marshal
 type InodeOld struct {
 	ModeRaw uint16
 	UIDLo   uint16
diff --git a/pkg/sentry/fsimpl/ext/disklayout/inode_test.go b/pkg/sentry/fsimpl/ext/disklayout/inode_test.go
index dd03ee50e..90744e956 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/inode_test.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/inode_test.go
@@ -24,10 +24,12 @@ import (
 
 // TestInodeSize tests that the inode structs are of the correct size.
 func TestInodeSize(t *testing.T) {
-	assertSize(t, InodeOld{}, OldInodeSize)
+	var iOld InodeOld
+	assertSize(t, &iOld, OldInodeSize)
 
 	// This was updated from 156 bytes to 160 bytes in Oct 2015.
-	assertSize(t, InodeNew{}, 160)
+	var iNew InodeNew
+	assertSize(t, &iNew, 160)
 }
 
 // TestTimestampSeconds tests that the seconds part of [a/c/m] timestamps in
diff --git a/pkg/sentry/fsimpl/ext/disklayout/superblock.go b/pkg/sentry/fsimpl/ext/disklayout/superblock.go
index 8bb327006..70948ebe9 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/superblock.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/superblock.go
@@ -14,6 +14,10 @@
 
 package disklayout
 
+import (
+	"gvisor.dev/gvisor/pkg/marshal"
+)
+
 const (
 	// SbOffset is the absolute offset at which the superblock is placed.
 	SbOffset = 1024
@@ -38,6 +42,8 @@ const (
 //
 // See https://www.kernel.org/doc/html/latest/filesystems/ext4/globals.html#super-block.
 type SuperBlock interface {
+	marshal.Marshallable
+
 	// InodesCount returns the total number of inodes in this filesystem.
 	InodesCount() uint32
 
diff --git a/pkg/sentry/fsimpl/ext/disklayout/superblock_32.go b/pkg/sentry/fsimpl/ext/disklayout/superblock_32.go
index 53e515fd3..4dc6080fb 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/superblock_32.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/superblock_32.go
@@ -17,6 +17,8 @@ package disklayout
 // SuperBlock32Bit implements SuperBlock and represents the 32-bit version of
 // the ext4_super_block struct in fs/ext4/ext4.h. Should be used only if
 // RevLevel = DynamicRev and 64-bit feature is disabled.
+//
+// +marshal
 type SuperBlock32Bit struct {
 	// We embed the old superblock struct here because the 32-bit version is just
 	// an extension of the old version.
diff --git a/pkg/sentry/fsimpl/ext/disklayout/superblock_64.go b/pkg/sentry/fsimpl/ext/disklayout/superblock_64.go
index 7c1053fb4..2c9039327 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/superblock_64.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/superblock_64.go
@@ -19,6 +19,8 @@ package disklayout
 // 1024 bytes (smallest possible block size) and hence the superblock always
 // fits in no more than one data block. Should only be used when the 64-bit
 // feature is set.
+//
+// +marshal
 type SuperBlock64Bit struct {
 	// We embed the 32-bit struct here because 64-bit version is just an extension
 	// of the 32-bit version.
diff --git a/pkg/sentry/fsimpl/ext/disklayout/superblock_old.go b/pkg/sentry/fsimpl/ext/disklayout/superblock_old.go
index 9221e0251..e4709f23c 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/superblock_old.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/superblock_old.go
@@ -16,6 +16,8 @@ package disklayout
 
 // SuperBlockOld implements SuperBlock and represents the old version of the
 // superblock struct. Should be used only if RevLevel = OldRev.
+//
+// +marshal
 type SuperBlockOld struct {
 	InodesCountRaw      uint32
 	BlocksCountLo       uint32
diff --git a/pkg/sentry/fsimpl/ext/disklayout/superblock_test.go b/pkg/sentry/fsimpl/ext/disklayout/superblock_test.go
index 463b5ba21..b734b6987 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/superblock_test.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/superblock_test.go
@@ -21,7 +21,10 @@ import (
 // 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)
+	var sbOld SuperBlockOld
+	assertSize(t, &sbOld, 84)
+	var sb32 SuperBlock32Bit
+	assertSize(t, &sb32, 336)
+	var sb64 SuperBlock64Bit
+	assertSize(t, &sb64, 1024)
 }
diff --git a/pkg/sentry/fsimpl/ext/disklayout/test_utils.go b/pkg/sentry/fsimpl/ext/disklayout/test_utils.go
index 9c63f04c0..a4bc08411 100644
--- a/pkg/sentry/fsimpl/ext/disklayout/test_utils.go
+++ b/pkg/sentry/fsimpl/ext/disklayout/test_utils.go
@@ -18,13 +18,13 @@ import (
 	"reflect"
 	"testing"
 
-	"gvisor.dev/gvisor/pkg/binary"
+	"gvisor.dev/gvisor/pkg/marshal"
 )
 
-func assertSize(t *testing.T, v interface{}, want uintptr) {
+func assertSize(t *testing.T, v marshal.Marshallable, want int) {
 	t.Helper()
 
-	if got := binary.Size(v); got != want {
+	if got := v.SizeBytes(); got != want {
 		t.Errorf("struct %s should be exactly %d bytes but is %d bytes", reflect.TypeOf(v).Name(), want, got)
 	}
 }