Merge release-20200818.0-100-g723fb5c11 (automated)

41 files changed, 306 insertions, 199 deletions

diff --git a/pkg/abi/linux/linux_abi_autogen_unsafe.go b/pkg/abi/linux/linux_abi_autogen_unsafe.go
index f4a3f4915..b4619a870 100644
--- a/pkg/abi/linux/linux_abi_autogen_unsafe.go
+++ b/pkg/abi/linux/linux_abi_autogen_unsafe.go
@@ -51,6 +51,7 @@ var _ marshal.Marshallable = (*Termios)(nil)
 var _ marshal.Marshallable = (*Timespec)(nil)
 var _ marshal.Marshallable = (*Timeval)(nil)
 var _ marshal.Marshallable = (*Utime)(nil)
+var _ marshal.Marshallable = (*WindowSize)(nil)
 var _ marshal.Marshallable = (*Winsize)(nil)
 var _ marshal.Marshallable = (*XTCounters)(nil)
 
@@ -159,7 +160,7 @@ func (s *Statx) Packed() bool {
 
 // MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
 func (s *Statx) MarshalUnsafe(dst []byte) {
-    if s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed() {
+    if s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() {
         safecopy.CopyIn(dst, unsafe.Pointer(s))
     } else {
         // Type Statx doesn't have a packed layout in memory, fallback to MarshalBytes.
@@ -169,7 +170,7 @@ func (s *Statx) MarshalUnsafe(dst []byte) {
 
 // UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
 func (s *Statx) UnmarshalUnsafe(src []byte) {
-    if s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed() && s.Atime.Packed() {
+    if s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed() {
         safecopy.CopyOut(unsafe.Pointer(s), src)
     } else {
         // Type Statx doesn't have a packed layout in memory, fallback to UnmarshalBytes.
@@ -180,7 +181,7 @@ func (s *Statx) UnmarshalUnsafe(src []byte) {
 // CopyOutN implements marshal.Marshallable.CopyOutN.
 //go:nosplit
 func (s *Statx) CopyOutN(task marshal.Task, addr usermem.Addr, limit int) (int, error) {
-    if !s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed() {
+    if !s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() {
         // Type Statx doesn't have a packed layout in memory, fall back to MarshalBytes.
         buf := task.CopyScratchBuffer(s.SizeBytes()) // escapes: okay.
         s.MarshalBytes(buf) // escapes: fallback.
@@ -210,7 +211,7 @@ func (s *Statx) CopyOut(task marshal.Task, addr usermem.Addr) (int, error) {
 // CopyIn implements marshal.Marshallable.CopyIn.
 //go:nosplit
 func (s *Statx) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
-    if !s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed() {
+    if !s.Ctime.Packed() && s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() {
         // Type Statx doesn't have a packed layout in memory, fall back to UnmarshalBytes.
         buf := task.CopyScratchBuffer(s.SizeBytes()) // escapes: okay.
         length, err := task.CopyInBytes(addr, buf) // escapes: okay.
@@ -634,7 +635,7 @@ func (f *FUSEHeaderIn) Packed() bool {
 
 // MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
 func (f *FUSEHeaderIn) MarshalUnsafe(dst []byte) {
-    if f.Opcode.Packed() && f.Unique.Packed() {
+    if f.Unique.Packed() && f.Opcode.Packed() {
         safecopy.CopyIn(dst, unsafe.Pointer(f))
     } else {
         // Type FUSEHeaderIn doesn't have a packed layout in memory, fallback to MarshalBytes.
@@ -711,7 +712,7 @@ func (f *FUSEHeaderIn) CopyIn(task marshal.Task, addr usermem.Addr) (int, error)
 
 // WriteTo implements io.WriterTo.WriteTo.
 func (f *FUSEHeaderIn) WriteTo(writer io.Writer) (int64, error) {
-    if !f.Opcode.Packed() && f.Unique.Packed() {
+    if !f.Unique.Packed() && f.Opcode.Packed() {
         // Type FUSEHeaderIn doesn't have a packed layout in memory, fall back to MarshalBytes.
         buf := make([]byte, f.SizeBytes())
         f.MarshalBytes(buf)
@@ -2078,7 +2079,7 @@ func (i *IPTEntry) CopyOut(task marshal.Task, addr usermem.Addr) (int, error) {
 // CopyIn implements marshal.Marshallable.CopyIn.
 //go:nosplit
 func (i *IPTEntry) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
-    if !i.IP.Packed() && i.Counters.Packed() {
+    if !i.Counters.Packed() && i.IP.Packed() {
         // Type IPTEntry doesn't have a packed layout in memory, fall back to UnmarshalBytes.
         buf := task.CopyScratchBuffer(i.SizeBytes()) // escapes: okay.
         length, err := task.CopyInBytes(addr, buf) // escapes: okay.
@@ -2215,7 +2216,7 @@ func (i *IPTIP) Packed() bool {
 
 // MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
 func (i *IPTIP) MarshalUnsafe(dst []byte) {
-    if i.DstMask.Packed() && i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() {
+    if i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() {
         safecopy.CopyIn(dst, unsafe.Pointer(i))
     } else {
         // Type IPTIP doesn't have a packed layout in memory, fallback to MarshalBytes.
@@ -2225,7 +2226,7 @@ func (i *IPTIP) MarshalUnsafe(dst []byte) {
 
 // UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
 func (i *IPTIP) UnmarshalUnsafe(src []byte) {
-    if i.DstMask.Packed() && i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() {
+    if i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() {
         safecopy.CopyOut(unsafe.Pointer(i), src)
     } else {
         // Type IPTIP doesn't have a packed layout in memory, fallback to UnmarshalBytes.
@@ -2266,7 +2267,7 @@ func (i *IPTIP) CopyOut(task marshal.Task, addr usermem.Addr) (int, error) {
 // CopyIn implements marshal.Marshallable.CopyIn.
 //go:nosplit
 func (i *IPTIP) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
-    if !i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() {
+    if !i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() && i.Src.Packed() {
         // Type IPTIP doesn't have a packed layout in memory, fall back to UnmarshalBytes.
         buf := task.CopyScratchBuffer(i.SizeBytes()) // escapes: okay.
         length, err := task.CopyInBytes(addr, buf) // escapes: okay.
@@ -2292,7 +2293,7 @@ func (i *IPTIP) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
 
 // WriteTo implements io.WriterTo.WriteTo.
 func (i *IPTIP) WriteTo(writer io.Writer) (int64, error) {
-    if !i.SrcMask.Packed() && i.DstMask.Packed() && i.Src.Packed() && i.Dst.Packed() {
+    if !i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() {
         // Type IPTIP doesn't have a packed layout in memory, fall back to MarshalBytes.
         buf := make([]byte, i.SizeBytes())
         i.MarshalBytes(buf)
@@ -3083,7 +3084,7 @@ func (i *IP6TEntry) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
 
 // WriteTo implements io.WriterTo.WriteTo.
 func (i *IP6TEntry) WriteTo(writer io.Writer) (int64, error) {
-    if !i.Counters.Packed() && i.IPv6.Packed() {
+    if !i.IPv6.Packed() && i.Counters.Packed() {
         // Type IP6TEntry doesn't have a packed layout in memory, fall back to MarshalBytes.
         buf := make([]byte, i.SizeBytes())
         i.MarshalBytes(buf)
@@ -3203,7 +3204,7 @@ func (i *IP6TIP) Packed() bool {
 
 // MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
 func (i *IP6TIP) MarshalUnsafe(dst []byte) {
-    if i.DstMask.Packed() && i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() {
+    if i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() {
         safecopy.CopyIn(dst, unsafe.Pointer(i))
     } else {
         // Type IP6TIP doesn't have a packed layout in memory, fallback to MarshalBytes.
@@ -3213,7 +3214,7 @@ func (i *IP6TIP) MarshalUnsafe(dst []byte) {
 
 // UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
 func (i *IP6TIP) UnmarshalUnsafe(src []byte) {
-    if i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() && i.Src.Packed() {
+    if i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() {
         safecopy.CopyOut(unsafe.Pointer(i), src)
     } else {
         // Type IP6TIP doesn't have a packed layout in memory, fallback to UnmarshalBytes.
@@ -3254,7 +3255,7 @@ func (i *IP6TIP) CopyOut(task marshal.Task, addr usermem.Addr) (int, error) {
 // CopyIn implements marshal.Marshallable.CopyIn.
 //go:nosplit
 func (i *IP6TIP) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
-    if !i.SrcMask.Packed() && i.DstMask.Packed() && i.Src.Packed() && i.Dst.Packed() {
+    if !i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() {
         // Type IP6TIP doesn't have a packed layout in memory, fall back to UnmarshalBytes.
         buf := task.CopyScratchBuffer(i.SizeBytes()) // escapes: okay.
         length, err := task.CopyInBytes(addr, buf) // escapes: okay.
@@ -4874,3 +4875,101 @@ func (t *Termios) WriteTo(writer io.Writer) (int64, error) {
     return int64(length), err
 }
 
+// SizeBytes implements marshal.Marshallable.SizeBytes.
+func (w *WindowSize) SizeBytes() int {
+    return 4 +
+        1*4
+}
+
+// MarshalBytes implements marshal.Marshallable.MarshalBytes.
+func (w *WindowSize) MarshalBytes(dst []byte) {
+    usermem.ByteOrder.PutUint16(dst[:2], uint16(w.Rows))
+    dst = dst[2:]
+    usermem.ByteOrder.PutUint16(dst[:2], uint16(w.Cols))
+    dst = dst[2:]
+    // Padding: dst[:sizeof(byte)*4] ~= [4]byte{0}
+    dst = dst[1*(4):]
+}
+
+// UnmarshalBytes implements marshal.Marshallable.UnmarshalBytes.
+func (w *WindowSize) UnmarshalBytes(src []byte) {
+    w.Rows = uint16(usermem.ByteOrder.Uint16(src[:2]))
+    src = src[2:]
+    w.Cols = uint16(usermem.ByteOrder.Uint16(src[:2]))
+    src = src[2:]
+    // Padding: ~ copy([4]byte(w._), src[:sizeof(byte)*4])
+    src = src[1*(4):]
+}
+
+// Packed implements marshal.Marshallable.Packed.
+//go:nosplit
+func (w *WindowSize) Packed() bool {
+    return true
+}
+
+// MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
+func (w *WindowSize) MarshalUnsafe(dst []byte) {
+    safecopy.CopyIn(dst, unsafe.Pointer(w))
+}
+
+// UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
+func (w *WindowSize) UnmarshalUnsafe(src []byte) {
+    safecopy.CopyOut(unsafe.Pointer(w), src)
+}
+
+// CopyOutN implements marshal.Marshallable.CopyOutN.
+//go:nosplit
+func (w *WindowSize) CopyOutN(task marshal.Task, addr usermem.Addr, limit int) (int, error) {
+    // Construct a slice backed by dst's underlying memory.
+    var buf []byte
+    hdr := (*reflect.SliceHeader)(unsafe.Pointer(&buf))
+    hdr.Data = uintptr(gohacks.Noescape(unsafe.Pointer(w)))
+    hdr.Len = w.SizeBytes()
+    hdr.Cap = w.SizeBytes()
+
+    length, err := task.CopyOutBytes(addr, buf[:limit]) // escapes: okay.
+    // Since we bypassed the compiler's escape analysis, indicate that w
+    // must live until the use above.
+    runtime.KeepAlive(w) // escapes: replaced by intrinsic.
+    return length, err
+}
+
+// CopyOut implements marshal.Marshallable.CopyOut.
+//go:nosplit
+func (w *WindowSize) CopyOut(task marshal.Task, addr usermem.Addr) (int, error) {
+    return w.CopyOutN(task, addr, w.SizeBytes())
+}
+
+// CopyIn implements marshal.Marshallable.CopyIn.
+//go:nosplit
+func (w *WindowSize) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
+    // Construct a slice backed by dst's underlying memory.
+    var buf []byte
+    hdr := (*reflect.SliceHeader)(unsafe.Pointer(&buf))
+    hdr.Data = uintptr(gohacks.Noescape(unsafe.Pointer(w)))
+    hdr.Len = w.SizeBytes()
+    hdr.Cap = w.SizeBytes()
+
+    length, err := task.CopyInBytes(addr, buf) // escapes: okay.
+    // Since we bypassed the compiler's escape analysis, indicate that w
+    // must live until the use above.
+    runtime.KeepAlive(w) // escapes: replaced by intrinsic.
+    return length, err
+}
+
+// WriteTo implements io.WriterTo.WriteTo.
+func (w *WindowSize) WriteTo(writer io.Writer) (int64, error) {
+    // Construct a slice backed by dst's underlying memory.
+    var buf []byte
+    hdr := (*reflect.SliceHeader)(unsafe.Pointer(&buf))
+    hdr.Data = uintptr(gohacks.Noescape(unsafe.Pointer(w)))
+    hdr.Len = w.SizeBytes()
+    hdr.Cap = w.SizeBytes()
+
+    length, err := writer.Write(buf)
+    // Since we bypassed the compiler's escape analysis, indicate that w
+    // must live until the use above.
+    runtime.KeepAlive(w) // escapes: replaced by intrinsic.
+    return int64(length), err
+}
+
diff --git a/pkg/abi/linux/linux_amd64_abi_autogen_unsafe.go b/pkg/abi/linux/linux_amd64_abi_autogen_unsafe.go
index 993834649..91e0e70ce 100644
--- a/pkg/abi/linux/linux_amd64_abi_autogen_unsafe.go
+++ b/pkg/abi/linux/linux_amd64_abi_autogen_unsafe.go
@@ -288,7 +288,7 @@ func (s *Stat) UnmarshalBytes(src []byte) {
 // Packed implements marshal.Marshallable.Packed.
 //go:nosplit
 func (s *Stat) Packed() bool {
-    return s.MTime.Packed() && s.CTime.Packed() && s.ATime.Packed()
+    return s.ATime.Packed() && s.MTime.Packed() && s.CTime.Packed()
 }
 
 // MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
diff --git a/pkg/abi/linux/linux_arm64_abi_autogen_unsafe.go b/pkg/abi/linux/linux_arm64_abi_autogen_unsafe.go
index 7a5f4e86c..dc2af8bc9 100644
--- a/pkg/abi/linux/linux_arm64_abi_autogen_unsafe.go
+++ b/pkg/abi/linux/linux_arm64_abi_autogen_unsafe.go
@@ -351,7 +351,7 @@ func (s *Stat) CopyOut(task marshal.Task, addr usermem.Addr) (int, error) {
 // CopyIn implements marshal.Marshallable.CopyIn.
 //go:nosplit
 func (s *Stat) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
-    if !s.ATime.Packed() && s.MTime.Packed() && s.CTime.Packed() {
+    if !s.MTime.Packed() && s.CTime.Packed() && s.ATime.Packed() {
         // Type Stat doesn't have a packed layout in memory, fall back to UnmarshalBytes.
         buf := task.CopyScratchBuffer(s.SizeBytes()) // escapes: okay.
         length, err := task.CopyInBytes(addr, buf) // escapes: okay.
diff --git a/pkg/abi/linux/tty.go b/pkg/abi/linux/tty.go
index e640969a6..5a5ff0aa2 100644
--- a/pkg/abi/linux/tty.go
+++ b/pkg/abi/linux/tty.go
@@ -341,6 +341,7 @@ var DefaultSlaveTermios = KernelTermios{
 // include/uapi/asm-generic/termios.h.
 //
 // +stateify savable
+// +marshal
 type WindowSize struct {
 	Rows uint16
 	Cols uint16
diff --git a/pkg/sentry/fs/tty/line_discipline.go b/pkg/sentry/fs/tty/line_discipline.go
index 2e9dd2d55..b6bc011a9 100644
--- a/pkg/sentry/fs/tty/line_discipline.go
+++ b/pkg/sentry/fs/tty/line_discipline.go
@@ -21,6 +21,7 @@ import (
 	"gvisor.dev/gvisor/pkg/abi/linux"
 	"gvisor.dev/gvisor/pkg/context"
 	"gvisor.dev/gvisor/pkg/sentry/arch"
+	"gvisor.dev/gvisor/pkg/sentry/kernel"
 	"gvisor.dev/gvisor/pkg/sync"
 	"gvisor.dev/gvisor/pkg/syserror"
 	"gvisor.dev/gvisor/pkg/usermem"
@@ -115,27 +116,23 @@ func newLineDiscipline(termios linux.KernelTermios) *lineDiscipline {
 }
 
 // getTermios gets the linux.Termios for the tty.
-func (l *lineDiscipline) getTermios(ctx context.Context, io usermem.IO, args arch.SyscallArguments) (uintptr, error) {
+func (l *lineDiscipline) getTermios(task *kernel.Task, args arch.SyscallArguments) (uintptr, error) {
 	l.termiosMu.RLock()
 	defer l.termiosMu.RUnlock()
 	// We must copy a Termios struct, not KernelTermios.
 	t := l.termios.ToTermios()
-	_, err := usermem.CopyObjectOut(ctx, io, args[2].Pointer(), t, usermem.IOOpts{
-		AddressSpaceActive: true,
-	})
+	_, err := t.CopyOut(task, args[2].Pointer())
 	return 0, err
 }
 
 // setTermios sets a linux.Termios for the tty.
-func (l *lineDiscipline) setTermios(ctx context.Context, io usermem.IO, args arch.SyscallArguments) (uintptr, error) {
+func (l *lineDiscipline) setTermios(task *kernel.Task, args arch.SyscallArguments) (uintptr, error) {
 	l.termiosMu.Lock()
 	defer l.termiosMu.Unlock()
 	oldCanonEnabled := l.termios.LEnabled(linux.ICANON)
 	// We must copy a Termios struct, not KernelTermios.
 	var t linux.Termios
-	_, err := usermem.CopyObjectIn(ctx, io, args[2].Pointer(), &t, usermem.IOOpts{
-		AddressSpaceActive: true,
-	})
+	_, err := t.CopyIn(task, args[2].Pointer())
 	l.termios.FromTermios(t)
 
 	// If canonical mode is turned off, move bytes from inQueue's wait
@@ -152,21 +149,17 @@ func (l *lineDiscipline) setTermios(ctx context.Context, io usermem.IO, args arc
 	return 0, err
 }
 
-func (l *lineDiscipline) windowSize(ctx context.Context, io usermem.IO, args arch.SyscallArguments) error {
+func (l *lineDiscipline) windowSize(t *kernel.Task, args arch.SyscallArguments) error {
 	l.sizeMu.Lock()
 	defer l.sizeMu.Unlock()
-	_, err := usermem.CopyObjectOut(ctx, io, args[2].Pointer(), l.size, usermem.IOOpts{
-		AddressSpaceActive: true,
-	})
+	_, err := l.size.CopyOut(t, args[2].Pointer())
 	return err
 }
 
-func (l *lineDiscipline) setWindowSize(ctx context.Context, io usermem.IO, args arch.SyscallArguments) error {
+func (l *lineDiscipline) setWindowSize(t *kernel.Task, args arch.SyscallArguments) error {
 	l.sizeMu.Lock()
 	defer l.sizeMu.Unlock()
-	_, err := usermem.CopyObjectIn(ctx, io, args[2].Pointer(), &l.size, usermem.IOOpts{
-		AddressSpaceActive: true,
-	})
+	_, err := l.size.CopyIn(t, args[2].Pointer())
 	return err
 }
 
@@ -182,8 +175,8 @@ func (l *lineDiscipline) slaveReadiness() waiter.EventMask {
 	return l.outQueue.writeReadiness(&l.termios) | l.inQueue.readReadiness(&l.termios)
 }
 
-func (l *lineDiscipline) inputQueueReadSize(ctx context.Context, io usermem.IO, args arch.SyscallArguments) error {
-	return l.inQueue.readableSize(ctx, io, args)
+func (l *lineDiscipline) inputQueueReadSize(t *kernel.Task, args arch.SyscallArguments) error {
+	return l.inQueue.readableSize(t, args)
 }
 
 func (l *lineDiscipline) inputQueueRead(ctx context.Context, dst usermem.IOSequence) (int64, error) {
@@ -217,8 +210,8 @@ func (l *lineDiscipline) inputQueueWrite(ctx context.Context, src usermem.IOSequ
 	return 0, syserror.ErrWouldBlock
 }
 
-func (l *lineDiscipline) outputQueueReadSize(ctx context.Context, io usermem.IO, args arch.SyscallArguments) error {
-	return l.outQueue.readableSize(ctx, io, args)
+func (l *lineDiscipline) outputQueueReadSize(t *kernel.Task, args arch.SyscallArguments) error {
+	return l.outQueue.readableSize(t, args)
 }
 
 func (l *lineDiscipline) outputQueueRead(ctx context.Context, dst usermem.IOSequence) (int64, error) {
diff --git a/pkg/sentry/fs/tty/master.go b/pkg/sentry/fs/tty/master.go
index e00746017..175457297 100644
--- a/pkg/sentry/fs/tty/master.go
+++ b/pkg/sentry/fs/tty/master.go
@@ -20,10 +20,12 @@ import (
 	"gvisor.dev/gvisor/pkg/sentry/arch"
 	"gvisor.dev/gvisor/pkg/sentry/fs"
 	"gvisor.dev/gvisor/pkg/sentry/fs/fsutil"
+	"gvisor.dev/gvisor/pkg/sentry/kernel"
 	"gvisor.dev/gvisor/pkg/sentry/unimpl"
 	"gvisor.dev/gvisor/pkg/syserror"
 	"gvisor.dev/gvisor/pkg/usermem"
 	"gvisor.dev/gvisor/pkg/waiter"
+	"gvisor.dev/gvisor/tools/go_marshal/primitive"
 )
 
 // LINT.IfChange
@@ -152,46 +154,51 @@ func (mf *masterFileOperations) Write(ctx context.Context, _ *fs.File, src userm
 
 // Ioctl implements fs.FileOperations.Ioctl.
 func (mf *masterFileOperations) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO, args arch.SyscallArguments) (uintptr, error) {
+	t := kernel.TaskFromContext(ctx)
+	if t == nil {
+		// ioctl(2) may only be called from a task goroutine.
+		return 0, syserror.ENOTTY
+	}
+
 	switch cmd := args[1].Uint(); cmd {
 	case linux.FIONREAD: // linux.FIONREAD == linux.TIOCINQ
 		// Get the number of bytes in the output queue read buffer.
-		return 0, mf.t.ld.outputQueueReadSize(ctx, io, args)
+		return 0, mf.t.ld.outputQueueReadSize(t, args)
 	case linux.TCGETS:
 		// N.B. TCGETS on the master actually returns the configuration
 		// of the slave end.
-		return mf.t.ld.getTermios(ctx, io, args)
+		return mf.t.ld.getTermios(t, args)
 	case linux.TCSETS:
 		// N.B. TCSETS on the master actually affects the configuration
 		// of the slave end.
-		return mf.t.ld.setTermios(ctx, io, args)
+		return mf.t.ld.setTermios(t, args)
 	case linux.TCSETSW:
 		// TODO(b/29356795): This should drain the output queue first.
-		return mf.t.ld.setTermios(ctx, io, args)
+		return mf.t.ld.setTermios(t, args)
 	case linux.TIOCGPTN:
-		_, err := usermem.CopyObjectOut(ctx, io, args[2].Pointer(), uint32(mf.t.n), usermem.IOOpts{
-			AddressSpaceActive: true,
-		})
+		nP := primitive.Uint32(mf.t.n)
+		_, err := nP.CopyOut(t, args[2].Pointer())
 		return 0, err
 	case linux.TIOCSPTLCK:
 		// TODO(b/29356795): Implement pty locking. For now just pretend we do.
 		return 0, nil
 	case linux.TIOCGWINSZ:
-		return 0, mf.t.ld.windowSize(ctx, io, args)
+		return 0, mf.t.ld.windowSize(t, args)
 	case linux.TIOCSWINSZ:
-		return 0, mf.t.ld.setWindowSize(ctx, io, args)
+		return 0, mf.t.ld.setWindowSize(t, args)
 	case linux.TIOCSCTTY:
 		// Make the given terminal the controlling terminal of the
 		// calling process.
-		return 0, mf.t.setControllingTTY(ctx, io, args, true /* isMaster */)
+		return 0, mf.t.setControllingTTY(ctx, args, true /* isMaster */)
 	case linux.TIOCNOTTY:
 		// Release this process's controlling terminal.
-		return 0, mf.t.releaseControllingTTY(ctx, io, args, true /* isMaster */)
+		return 0, mf.t.releaseControllingTTY(ctx, args, true /* isMaster */)
 	case linux.TIOCGPGRP:
 		// Get the foreground process group.
-		return mf.t.foregroundProcessGroup(ctx, io, args, true /* isMaster */)
+		return mf.t.foregroundProcessGroup(ctx, args, true /* isMaster */)
 	case linux.TIOCSPGRP:
 		// Set the foreground process group.
-		return mf.t.setForegroundProcessGroup(ctx, io, args, true /* isMaster */)
+		return mf.t.setForegroundProcessGroup(ctx, args, true /* isMaster */)
 	default:
 		maybeEmitUnimplementedEvent(ctx, cmd)
 		return 0, syserror.ENOTTY
diff --git a/pkg/sentry/fs/tty/queue.go b/pkg/sentry/fs/tty/queue.go
index c5d7ec717..f0a18c75a 100644
--- a/pkg/sentry/fs/tty/queue.go
+++ b/pkg/sentry/fs/tty/queue.go
@@ -19,10 +19,12 @@ import (
 	"gvisor.dev/gvisor/pkg/context"
 	"gvisor.dev/gvisor/pkg/safemem"
 	"gvisor.dev/gvisor/pkg/sentry/arch"
+	"gvisor.dev/gvisor/pkg/sentry/kernel"
 	"gvisor.dev/gvisor/pkg/sync"
 	"gvisor.dev/gvisor/pkg/syserror"
 	"gvisor.dev/gvisor/pkg/usermem"
 	"gvisor.dev/gvisor/pkg/waiter"
+	"gvisor.dev/gvisor/tools/go_marshal/primitive"
 )
 
 // LINT.IfChange
@@ -85,17 +87,15 @@ func (q *queue) writeReadiness(t *linux.KernelTermios) waiter.EventMask {
 }
 
 // readableSize writes the number of readable bytes to userspace.
-func (q *queue) readableSize(ctx context.Context, io usermem.IO, args arch.SyscallArguments) error {
+func (q *queue) readableSize(t *kernel.Task, args arch.SyscallArguments) error {
 	q.mu.Lock()
 	defer q.mu.Unlock()
-	var size int32
+	size := primitive.Int32(0)
 	if q.readable {
-		size = int32(len(q.readBuf))
+		size = primitive.Int32(len(q.readBuf))
 	}
 
-	_, err := usermem.CopyObjectOut(ctx, io, args[2].Pointer(), size, usermem.IOOpts{
-		AddressSpaceActive: true,
-	})
+	_, err := size.CopyOut(t, args[2].Pointer())
 	return err
 
 }
diff --git a/pkg/sentry/fs/tty/slave.go b/pkg/sentry/fs/tty/slave.go
index 7c7292687..933d2c3ff 100644
--- a/pkg/sentry/fs/tty/slave.go
+++ b/pkg/sentry/fs/tty/slave.go
@@ -20,9 +20,11 @@ import (
 	"gvisor.dev/gvisor/pkg/sentry/arch"
 	"gvisor.dev/gvisor/pkg/sentry/fs"
 	"gvisor.dev/gvisor/pkg/sentry/fs/fsutil"
+	"gvisor.dev/gvisor/pkg/sentry/kernel"
 	"gvisor.dev/gvisor/pkg/syserror"
 	"gvisor.dev/gvisor/pkg/usermem"
 	"gvisor.dev/gvisor/pkg/waiter"
+	"gvisor.dev/gvisor/tools/go_marshal/primitive"
 )
 
 // LINT.IfChange
@@ -136,39 +138,44 @@ func (sf *slaveFileOperations) Write(ctx context.Context, _ *fs.File, src userme
 
 // Ioctl implements fs.FileOperations.Ioctl.
 func (sf *slaveFileOperations) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO, args arch.SyscallArguments) (uintptr, error) {
+	t := kernel.TaskFromContext(ctx)
+	if t == nil {
+		// ioctl(2) may only be called from a task goroutine.
+		return 0, syserror.ENOTTY
+	}
+
 	switch cmd := args[1].Uint(); cmd {
 	case linux.FIONREAD: // linux.FIONREAD == linux.TIOCINQ
 		// Get the number of bytes in the input queue read buffer.
-		return 0, sf.si.t.ld.inputQueueReadSize(ctx, io, args)
+		return 0, sf.si.t.ld.inputQueueReadSize(t, args)
 	case linux.TCGETS:
-		return sf.si.t.ld.getTermios(ctx, io, args)
+		return sf.si.t.ld.getTermios(t, args)
 	case linux.TCSETS:
-		return sf.si.t.ld.setTermios(ctx, io, args)
+		return sf.si.t.ld.setTermios(t, args)
 	case linux.TCSETSW:
 		// TODO(b/29356795): This should drain the output queue first.
-		return sf.si.t.ld.setTermios(ctx, io, args)
+		return sf.si.t.ld.setTermios(t, args)
 	case linux.TIOCGPTN:
-		_, err := usermem.CopyObjectOut(ctx, io, args[2].Pointer(), uint32(sf.si.t.n), usermem.IOOpts{
-			AddressSpaceActive: true,
-		})
+		nP := primitive.Uint32(sf.si.t.n)
+		_, err := nP.CopyOut(t, args[2].Pointer())
 		return 0, err
 	case linux.TIOCGWINSZ:
-		return 0, sf.si.t.ld.windowSize(ctx, io, args)
+		return 0, sf.si.t.ld.windowSize(t, args)
 	case linux.TIOCSWINSZ:
-		return 0, sf.si.t.ld.setWindowSize(ctx, io, args)
+		return 0, sf.si.t.ld.setWindowSize(t, args)
 	case linux.TIOCSCTTY:
 		// Make the given terminal the controlling terminal of the
 		// calling process.
-		return 0, sf.si.t.setControllingTTY(ctx, io, args, false /* isMaster */)
+		return 0, sf.si.t.setControllingTTY(ctx, args, false /* isMaster */)
 	case linux.TIOCNOTTY:
 		// Release this process's controlling terminal.
-		return 0, sf.si.t.releaseControllingTTY(ctx, io, args, false /* isMaster */)
+		return 0, sf.si.t.releaseControllingTTY(ctx, args, false /* isMaster */)
 	case linux.TIOCGPGRP:
 		// Get the foreground process group.
-		return sf.si.t.foregroundProcessGroup(ctx, io, args, false /* isMaster */)
+		return sf.si.t.foregroundProcessGroup(ctx, args, false /* isMaster */)
 	case linux.TIOCSPGRP:
 		// Set the foreground process group.
-		return sf.si.t.setForegroundProcessGroup(ctx, io, args, false /* isMaster */)
+		return sf.si.t.setForegroundProcessGroup(ctx, args, false /* isMaster */)
 	default:
 		maybeEmitUnimplementedEvent(ctx, cmd)
 		return 0, syserror.ENOTTY
diff --git a/pkg/sentry/fs/tty/terminal.go b/pkg/sentry/fs/tty/terminal.go
index ddcccf4da..56b59632d 100644
--- a/pkg/sentry/fs/tty/terminal.go
+++ b/pkg/sentry/fs/tty/terminal.go
@@ -20,7 +20,7 @@ import (
 	"gvisor.dev/gvisor/pkg/refs"
 	"gvisor.dev/gvisor/pkg/sentry/arch"
 	"gvisor.dev/gvisor/pkg/sentry/kernel"
-	"gvisor.dev/gvisor/pkg/usermem"
+	"gvisor.dev/gvisor/tools/go_marshal/primitive"
 )
 
 // LINT.IfChange
@@ -64,7 +64,7 @@ func newTerminal(ctx context.Context, d *dirInodeOperations, n uint32) *Terminal
 
 // setControllingTTY makes tm the controlling terminal of the calling thread
 // group.
-func (tm *Terminal) setControllingTTY(ctx context.Context, io usermem.IO, args arch.SyscallArguments, isMaster bool) error {
+func (tm *Terminal) setControllingTTY(ctx context.Context, args arch.SyscallArguments, isMaster bool) error {
 	task := kernel.TaskFromContext(ctx)
 	if task == nil {
 		panic("setControllingTTY must be called from a task context")
@@ -75,7 +75,7 @@ func (tm *Terminal) setControllingTTY(ctx context.Context, io usermem.IO, args a
 
 // releaseControllingTTY removes tm as the controlling terminal of the calling
 // thread group.
-func (tm *Terminal) releaseControllingTTY(ctx context.Context, io usermem.IO, args arch.SyscallArguments, isMaster bool) error {
+func (tm *Terminal) releaseControllingTTY(ctx context.Context, args arch.SyscallArguments, isMaster bool) error {
 	task := kernel.TaskFromContext(ctx)
 	if task == nil {
 		panic("releaseControllingTTY must be called from a task context")
@@ -85,7 +85,7 @@ func (tm *Terminal) releaseControllingTTY(ctx context.Context, io usermem.IO, ar
 }
 
 // foregroundProcessGroup gets the process group ID of tm's foreground process.
-func (tm *Terminal) foregroundProcessGroup(ctx context.Context, io usermem.IO, args arch.SyscallArguments, isMaster bool) (uintptr, error) {
+func (tm *Terminal) foregroundProcessGroup(ctx context.Context, args arch.SyscallArguments, isMaster bool) (uintptr, error) {
 	task := kernel.TaskFromContext(ctx)
 	if task == nil {
 		panic("foregroundProcessGroup must be called from a task context")
@@ -97,24 +97,21 @@ func (tm *Terminal) foregroundProcessGroup(ctx context.Context, io usermem.IO, a
 	}
 
 	// Write it out to *arg.
-	_, err = usermem.CopyObjectOut(ctx, io, args[2].Pointer(), int32(ret), usermem.IOOpts{
-		AddressSpaceActive: true,
-	})
+	retP := primitive.Int32(ret)
+	_, err = retP.CopyOut(task, args[2].Pointer())
 	return 0, err
 }
 
 // foregroundProcessGroup sets tm's foreground process.
-func (tm *Terminal) setForegroundProcessGroup(ctx context.Context, io usermem.IO, args arch.SyscallArguments, isMaster bool) (uintptr, error) {
+func (tm *Terminal) setForegroundProcessGroup(ctx context.Context, args arch.SyscallArguments, isMaster bool) (uintptr, error) {
 	task := kernel.TaskFromContext(ctx)
 	if task == nil {
 		panic("setForegroundProcessGroup must be called from a task context")
 	}
 
 	// Read in the process group ID.
-	var pgid int32
-	if _, err := usermem.CopyObjectIn(ctx, io, args[2].Pointer(), &pgid, usermem.IOOpts{
-		AddressSpaceActive: true,
-	}); err != nil {
+	var pgid primitive.Int32
+	if _, err := pgid.CopyIn(task, args[2].Pointer()); err != nil {
 		return 0, err
 	}
 
diff --git a/pkg/sentry/fsimpl/devpts/line_discipline.go b/pkg/sentry/fsimpl/devpts/line_discipline.go
index f7bc325d1..b954c1ba1 100644
--- a/pkg/sentry/fsimpl/devpts/line_discipline.go
+++ b/pkg/sentry/fsimpl/devpts/line_discipline.go
@@ -21,6 +21,7 @@ import (
 	"gvisor.dev/gvisor/pkg/abi/linux"
 	"gvisor.dev/gvisor/pkg/context"
 	"gvisor.dev/gvisor/pkg/sentry/arch"
+	"gvisor.dev/gvisor/pkg/sentry/kernel"
 	"gvisor.dev/gvisor/pkg/sync"
 	"gvisor.dev/gvisor/pkg/syserror"
 	"gvisor.dev/gvisor/pkg/usermem"
@@ -113,27 +114,23 @@ func newLineDiscipline(termios linux.KernelTermios) *lineDiscipline {
 }
 
 // getTermios gets the linux.Termios for the tty.
-func (l *lineDiscipline) getTermios(ctx context.Context, io usermem.IO, args arch.SyscallArguments) (uintptr, error) {
+func (l *lineDiscipline) getTermios(task *kernel.Task, args arch.SyscallArguments) (uintptr, error) {
 	l.termiosMu.RLock()
 	defer l.termiosMu.RUnlock()
 	// We must copy a Termios struct, not KernelTermios.
 	t := l.termios.ToTermios()
-	_, err := usermem.CopyObjectOut(ctx, io, args[2].Pointer(), t, usermem.IOOpts{
-		AddressSpaceActive: true,
-	})
+	_, err := t.CopyOut(task, args[2].Pointer())
 	return 0, err
 }
 
 // setTermios sets a linux.Termios for the tty.
-func (l *lineDiscipline) setTermios(ctx context.Context, io usermem.IO, args arch.SyscallArguments) (uintptr, error) {
+func (l *lineDiscipline) setTermios(task *kernel.Task, args arch.SyscallArguments) (uintptr, error) {
 	l.termiosMu.Lock()
 	defer l.termiosMu.Unlock()
 	oldCanonEnabled := l.termios.LEnabled(linux.ICANON)
 	// We must copy a Termios struct, not KernelTermios.
 	var t linux.Termios
-	_, err := usermem.CopyObjectIn(ctx, io, args[2].Pointer(), &t, usermem.IOOpts{
-		AddressSpaceActive: true,
-	})
+	_, err := t.CopyIn(task, args[2].Pointer())
 	l.termios.FromTermios(t)
 
 	// If canonical mode is turned off, move bytes from inQueue's wait
@@ -150,21 +147,17 @@ func (l *lineDiscipline) setTermios(ctx context.Context, io usermem.IO, args arc
 	return 0, err
 }
 
-func (l *lineDiscipline) windowSize(ctx context.Context, io usermem.IO, args arch.SyscallArguments) error {
+func (l *lineDiscipline) windowSize(t *kernel.Task, args arch.SyscallArguments) error {
 	l.sizeMu.Lock()
 	defer l.sizeMu.Unlock()
-	_, err := usermem.CopyObjectOut(ctx, io, args[2].Pointer(), l.size, usermem.IOOpts{
-		AddressSpaceActive: true,
-	})
+	_, err := l.size.CopyOut(t, args[2].Pointer())
 	return err
 }
 
-func (l *lineDiscipline) setWindowSize(ctx context.Context, io usermem.IO, args arch.SyscallArguments) error {
+func (l *lineDiscipline) setWindowSize(t *kernel.Task, args arch.SyscallArguments) error {
 	l.sizeMu.Lock()
 	defer l.sizeMu.Unlock()
-	_, err := usermem.CopyObjectIn(ctx, io, args[2].Pointer(), &l.size, usermem.IOOpts{
-		AddressSpaceActive: true,
-	})
+	_, err := l.size.CopyIn(t, args[2].Pointer())
 	return err
 }
 
@@ -180,8 +173,8 @@ func (l *lineDiscipline) slaveReadiness() waiter.EventMask {
 	return l.outQueue.writeReadiness(&l.termios) | l.inQueue.readReadiness(&l.termios)
 }
 
-func (l *lineDiscipline) inputQueueReadSize(ctx context.Context, io usermem.IO, args arch.SyscallArguments) error {
-	return l.inQueue.readableSize(ctx, io, args)
+func (l *lineDiscipline) inputQueueReadSize(t *kernel.Task, io usermem.IO, args arch.SyscallArguments) error {
+	return l.inQueue.readableSize(t, io, args)
 }
 
 func (l *lineDiscipline) inputQueueRead(ctx context.Context, dst usermem.IOSequence) (int64, error) {
@@ -215,8 +208,8 @@ func (l *lineDiscipline) inputQueueWrite(ctx context.Context, src usermem.IOSequ
 	return 0, syserror.ErrWouldBlock
 }
 
-func (l *lineDiscipline) outputQueueReadSize(ctx context.Context, io usermem.IO, args arch.SyscallArguments) error {
-	return l.outQueue.readableSize(ctx, io, args)
+func (l *lineDiscipline) outputQueueReadSize(t *kernel.Task, io usermem.IO, args arch.SyscallArguments) error {
+	return l.outQueue.readableSize(t, io, args)
 }
 
 func (l *lineDiscipline) outputQueueRead(ctx context.Context, dst usermem.IOSequence) (int64, error) {
diff --git a/pkg/sentry/fsimpl/devpts/master.go b/pkg/sentry/fsimpl/devpts/master.go
index 60feb1993..3422db6a4 100644
--- a/pkg/sentry/fsimpl/devpts/master.go
+++ b/pkg/sentry/fsimpl/devpts/master.go
@@ -20,12 +20,14 @@ import (
 	"gvisor.dev/gvisor/pkg/sentry/arch"
 	fslock "gvisor.dev/gvisor/pkg/sentry/fs/lock"
 	"gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs"
+	"gvisor.dev/gvisor/pkg/sentry/kernel"
 	"gvisor.dev/gvisor/pkg/sentry/kernel/auth"
 	"gvisor.dev/gvisor/pkg/sentry/unimpl"
 	"gvisor.dev/gvisor/pkg/sentry/vfs"
 	"gvisor.dev/gvisor/pkg/syserror"
 	"gvisor.dev/gvisor/pkg/usermem"
 	"gvisor.dev/gvisor/pkg/waiter"
+	"gvisor.dev/gvisor/tools/go_marshal/primitive"
 )
 
 // masterInode is the inode for the master end of the Terminal.
@@ -131,46 +133,51 @@ func (mfd *masterFileDescription) Write(ctx context.Context, src usermem.IOSeque
 
 // Ioctl implements vfs.FileDescriptionImpl.Ioctl.
 func (mfd *masterFileDescription) Ioctl(ctx context.Context, io usermem.IO, args arch.SyscallArguments) (uintptr, error) {
+	t := kernel.TaskFromContext(ctx)
+	if t == nil {
+		// ioctl(2) may only be called from a task goroutine.
+		return 0, syserror.ENOTTY
+	}
+
 	switch cmd := args[1].Uint(); cmd {
 	case linux.FIONREAD: // linux.FIONREAD == linux.TIOCINQ
 		// Get the number of bytes in the output queue read buffer.
-		return 0, mfd.t.ld.outputQueueReadSize(ctx, io, args)
+		return 0, mfd.t.ld.outputQueueReadSize(t, io, args)
 	case linux.TCGETS:
 		// N.B. TCGETS on the master actually returns the configuration
 		// of the slave end.
-		return mfd.t.ld.getTermios(ctx, io, args)
+		return mfd.t.ld.getTermios(t, args)
 	case linux.TCSETS:
 		// N.B. TCSETS on the master actually affects the configuration
 		// of the slave end.
-		return mfd.t.ld.setTermios(ctx, io, args)
+		return mfd.t.ld.setTermios(t, args)
 	case linux.TCSETSW:
 		// TODO(b/29356795): This should drain the output queue first.
-		return mfd.t.ld.setTermios(ctx, io, args)
+		return mfd.t.ld.setTermios(t, args)
 	case linux.TIOCGPTN:
-		_, err := usermem.CopyObjectOut(ctx, io, args[2].Pointer(), uint32(mfd.t.n), usermem.IOOpts{
-			AddressSpaceActive: true,
-		})
+		nP := primitive.Uint32(mfd.t.n)
+		_, err := nP.CopyOut(t, args[2].Pointer())
 		return 0, err
 	case linux.TIOCSPTLCK:
 		// TODO(b/29356795): Implement pty locking. For now just pretend we do.
 		return 0, nil
 	case linux.TIOCGWINSZ:
-		return 0, mfd.t.ld.windowSize(ctx, io, args)
+		return 0, mfd.t.ld.windowSize(t, args)
 	case linux.TIOCSWINSZ:
-		return 0, mfd.t.ld.setWindowSize(ctx, io, args)
+		return 0, mfd.t.ld.setWindowSize(t, args)
 	case linux.TIOCSCTTY:
 		// Make the given terminal the controlling terminal of the
 		// calling process.
-		return 0, mfd.t.setControllingTTY(ctx, io, args, true /* isMaster */)
+		return 0, mfd.t.setControllingTTY(ctx, args, true /* isMaster */)
 	case linux.TIOCNOTTY:
 		// Release this process's controlling terminal.
-		return 0, mfd.t.releaseControllingTTY(ctx, io, args, true /* isMaster */)
+		return 0, mfd.t.releaseControllingTTY(ctx, args, true /* isMaster */)
 	case linux.TIOCGPGRP:
 		// Get the foreground process group.
-		return mfd.t.foregroundProcessGroup(ctx, io, args, true /* isMaster */)
+		return mfd.t.foregroundProcessGroup(ctx, args, true /* isMaster */)
 	case linux.TIOCSPGRP:
 		// Set the foreground process group.
-		return mfd.t.setForegroundProcessGroup(ctx, io, args, true /* isMaster */)
+		return mfd.t.setForegroundProcessGroup(ctx, args, true /* isMaster */)
 	default:
 		maybeEmitUnimplementedEvent(ctx, cmd)
 		return 0, syserror.ENOTTY
diff --git a/pkg/sentry/fsimpl/devpts/queue.go b/pkg/sentry/fsimpl/devpts/queue.go
index 331c13997..08eca2589 100644
--- a/pkg/sentry/fsimpl/devpts/queue.go
+++ b/pkg/sentry/fsimpl/devpts/queue.go
@@ -19,10 +19,12 @@ import (
 	"gvisor.dev/gvisor/pkg/context"
 	"gvisor.dev/gvisor/pkg/safemem"
 	"gvisor.dev/gvisor/pkg/sentry/arch"
+	"gvisor.dev/gvisor/pkg/sentry/kernel"
 	"gvisor.dev/gvisor/pkg/sync"
 	"gvisor.dev/gvisor/pkg/syserror"
 	"gvisor.dev/gvisor/pkg/usermem"
 	"gvisor.dev/gvisor/pkg/waiter"
+	"gvisor.dev/gvisor/tools/go_marshal/primitive"
 )
 
 // waitBufMaxBytes is the maximum size of a wait buffer. It is based on
@@ -83,17 +85,15 @@ func (q *queue) writeReadiness(t *linux.KernelTermios) waiter.EventMask {
 }
 
 // readableSize writes the number of readable bytes to userspace.
-func (q *queue) readableSize(ctx context.Context, io usermem.IO, args arch.SyscallArguments) error {
+func (q *queue) readableSize(t *kernel.Task, io usermem.IO, args arch.SyscallArguments) error {
 	q.mu.Lock()
 	defer q.mu.Unlock()
-	var size int32
+	size := primitive.Int32(0)
 	if q.readable {
-		size = int32(len(q.readBuf))
+		size = primitive.Int32(len(q.readBuf))
 	}
 
-	_, err := usermem.CopyObjectOut(ctx, io, args[2].Pointer(), size, usermem.IOOpts{
-		AddressSpaceActive: true,
-	})
+	_, err := size.CopyOut(t, args[2].Pointer())
 	return err
 
 }
diff --git a/pkg/sentry/fsimpl/devpts/root_inode_refs.go b/pkg/sentry/fsimpl/devpts/root_inode_refs.go
index 1b7090229..068ee2f20 100644
--- a/pkg/sentry/fsimpl/devpts/root_inode_refs.go
+++ b/pkg/sentry/fsimpl/devpts/root_inode_refs.go
@@ -1,12 +1,12 @@
 package devpts
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/devpts/slave.go b/pkg/sentry/fsimpl/devpts/slave.go
index a9da7af64..5f4b474b3 100644
--- a/pkg/sentry/fsimpl/devpts/slave.go
+++ b/pkg/sentry/fsimpl/devpts/slave.go
@@ -20,11 +20,13 @@ import (
 	"gvisor.dev/gvisor/pkg/sentry/arch"
 	fslock "gvisor.dev/gvisor/pkg/sentry/fs/lock"
 	"gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs"
+	"gvisor.dev/gvisor/pkg/sentry/kernel"
 	"gvisor.dev/gvisor/pkg/sentry/kernel/auth"
 	"gvisor.dev/gvisor/pkg/sentry/vfs"
 	"gvisor.dev/gvisor/pkg/syserror"
 	"gvisor.dev/gvisor/pkg/usermem"
 	"gvisor.dev/gvisor/pkg/waiter"
+	"gvisor.dev/gvisor/tools/go_marshal/primitive"
 )
 
 // slaveInode is the inode for the slave end of the Terminal.
@@ -135,39 +137,44 @@ func (sfd *slaveFileDescription) Write(ctx context.Context, src usermem.IOSequen
 
 // Ioctl implements vfs.FileDescriptionImpl.Ioctl.
 func (sfd *slaveFileDescription) Ioctl(ctx context.Context, io usermem.IO, args arch.SyscallArguments) (uintptr, error) {
+	t := kernel.TaskFromContext(ctx)
+	if t == nil {
+		// ioctl(2) may only be called from a task goroutine.
+		return 0, syserror.ENOTTY
+	}
+
 	switch cmd := args[1].Uint(); cmd {
 	case linux.FIONREAD: // linux.FIONREAD == linux.TIOCINQ
 		// Get the number of bytes in the input queue read buffer.
-		return 0, sfd.inode.t.ld.inputQueueReadSize(ctx, io, args)
+		return 0, sfd.inode.t.ld.inputQueueReadSize(t, io, args)
 	case linux.TCGETS:
-		return sfd.inode.t.ld.getTermios(ctx, io, args)
+		return sfd.inode.t.ld.getTermios(t, args)
 	case linux.TCSETS:
-		return sfd.inode.t.ld.setTermios(ctx, io, args)
+		return sfd.inode.t.ld.setTermios(t, args)
 	case linux.TCSETSW:
 		// TODO(b/29356795): This should drain the output queue first.
-		return sfd.inode.t.ld.setTermios(ctx, io, args)
+		return sfd.inode.t.ld.setTermios(t, args)
 	case linux.TIOCGPTN:
-		_, err := usermem.CopyObjectOut(ctx, io, args[2].Pointer(), uint32(sfd.inode.t.n), usermem.IOOpts{
-			AddressSpaceActive: true,
-		})
+		nP := primitive.Uint32(sfd.inode.t.n)
+		_, err := nP.CopyOut(t, args[2].Pointer())
 		return 0, err
 	case linux.TIOCGWINSZ:
-		return 0, sfd.inode.t.ld.windowSize(ctx, io, args)
+		return 0, sfd.inode.t.ld.windowSize(t, args)
 	case linux.TIOCSWINSZ:
-		return 0, sfd.inode.t.ld.setWindowSize(ctx, io, args)
+		return 0, sfd.inode.t.ld.setWindowSize(t, args)
 	case linux.TIOCSCTTY:
 		// Make the given terminal the controlling terminal of the
 		// calling process.
-		return 0, sfd.inode.t.setControllingTTY(ctx, io, args, false /* isMaster */)
+		return 0, sfd.inode.t.setControllingTTY(ctx, args, false /* isMaster */)
 	case linux.TIOCNOTTY:
 		// Release this process's controlling terminal.
-		return 0, sfd.inode.t.releaseControllingTTY(ctx, io, args, false /* isMaster */)
+		return 0, sfd.inode.t.releaseControllingTTY(ctx, args, false /* isMaster */)
 	case linux.TIOCGPGRP:
 		// Get the foreground process group.
-		return sfd.inode.t.foregroundProcessGroup(ctx, io, args, false /* isMaster */)
+		return sfd.inode.t.foregroundProcessGroup(ctx, args, false /* isMaster */)
 	case linux.TIOCSPGRP:
 		// Set the foreground process group.
-		return sfd.inode.t.setForegroundProcessGroup(ctx, io, args, false /* isMaster */)
+		return sfd.inode.t.setForegroundProcessGroup(ctx, args, false /* isMaster */)
 	default:
 		maybeEmitUnimplementedEvent(ctx, cmd)
 		return 0, syserror.ENOTTY
diff --git a/pkg/sentry/fsimpl/devpts/terminal.go b/pkg/sentry/fsimpl/devpts/terminal.go
index 7d2781c54..e88eb6360 100644
--- a/pkg/sentry/fsimpl/devpts/terminal.go
+++ b/pkg/sentry/fsimpl/devpts/terminal.go
@@ -19,7 +19,7 @@ import (
 	"gvisor.dev/gvisor/pkg/context"
 	"gvisor.dev/gvisor/pkg/sentry/arch"
 	"gvisor.dev/gvisor/pkg/sentry/kernel"
-	"gvisor.dev/gvisor/pkg/usermem"
+	"gvisor.dev/gvisor/tools/go_marshal/primitive"
 )
 
 // Terminal is a pseudoterminal.
@@ -54,7 +54,7 @@ func newTerminal(n uint32) *Terminal {
 
 // setControllingTTY makes tm the controlling terminal of the calling thread
 // group.
-func (tm *Terminal) setControllingTTY(ctx context.Context, io usermem.IO, args arch.SyscallArguments, isMaster bool) error {
+func (tm *Terminal) setControllingTTY(ctx context.Context, args arch.SyscallArguments, isMaster bool) error {
 	task := kernel.TaskFromContext(ctx)
 	if task == nil {
 		panic("setControllingTTY must be called from a task context")
@@ -65,7 +65,7 @@ func (tm *Terminal) setControllingTTY(ctx context.Context, io usermem.IO, args a
 
 // releaseControllingTTY removes tm as the controlling terminal of the calling
 // thread group.
-func (tm *Terminal) releaseControllingTTY(ctx context.Context, io usermem.IO, args arch.SyscallArguments, isMaster bool) error {
+func (tm *Terminal) releaseControllingTTY(ctx context.Context, args arch.SyscallArguments, isMaster bool) error {
 	task := kernel.TaskFromContext(ctx)
 	if task == nil {
 		panic("releaseControllingTTY must be called from a task context")
@@ -75,7 +75,7 @@ func (tm *Terminal) releaseControllingTTY(ctx context.Context, io usermem.IO, ar
 }
 
 // foregroundProcessGroup gets the process group ID of tm's foreground process.
-func (tm *Terminal) foregroundProcessGroup(ctx context.Context, io usermem.IO, args arch.SyscallArguments, isMaster bool) (uintptr, error) {
+func (tm *Terminal) foregroundProcessGroup(ctx context.Context, args arch.SyscallArguments, isMaster bool) (uintptr, error) {
 	task := kernel.TaskFromContext(ctx)
 	if task == nil {
 		panic("foregroundProcessGroup must be called from a task context")
@@ -87,24 +87,21 @@ func (tm *Terminal) foregroundProcessGroup(ctx context.Context, io usermem.IO, a
 	}
 
 	// Write it out to *arg.
-	_, err = usermem.CopyObjectOut(ctx, io, args[2].Pointer(), int32(ret), usermem.IOOpts{
-		AddressSpaceActive: true,
-	})
+	retP := primitive.Int32(ret)
+	_, err = retP.CopyOut(task, args[2].Pointer())
 	return 0, err
 }
 
 // foregroundProcessGroup sets tm's foreground process.
-func (tm *Terminal) setForegroundProcessGroup(ctx context.Context, io usermem.IO, args arch.SyscallArguments, isMaster bool) (uintptr, error) {
+func (tm *Terminal) setForegroundProcessGroup(ctx context.Context, args arch.SyscallArguments, isMaster bool) (uintptr, error) {
 	task := kernel.TaskFromContext(ctx)
 	if task == nil {
 		panic("setForegroundProcessGroup must be called from a task context")
 	}
 
 	// Read in the process group ID.
-	var pgid int32
-	if _, err := usermem.CopyObjectIn(ctx, io, args[2].Pointer(), &pgid, usermem.IOOpts{
-		AddressSpaceActive: true,
-	}); err != nil {
+	var pgid primitive.Int32
+	if _, err := pgid.CopyIn(task, args[2].Pointer()); err != nil {
 		return 0, err
 	}
 
diff --git a/pkg/sentry/fsimpl/fuse/inode_refs.go b/pkg/sentry/fsimpl/fuse/inode_refs.go
index 12e7d6e6c..5d1de6067 100644
--- a/pkg/sentry/fsimpl/fuse/inode_refs.go
+++ b/pkg/sentry/fsimpl/fuse/inode_refs.go
@@ -1,12 +1,12 @@
 package fuse
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/host/connected_endpoint_refs.go b/pkg/sentry/fsimpl/host/connected_endpoint_refs.go
index 7fa5a516d..abf4a9082 100644
--- a/pkg/sentry/fsimpl/host/connected_endpoint_refs.go
+++ b/pkg/sentry/fsimpl/host/connected_endpoint_refs.go
@@ -1,12 +1,12 @@
 package host
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/host/inode_refs.go b/pkg/sentry/fsimpl/host/inode_refs.go
index c294b8b80..75b9f49e2 100644
--- a/pkg/sentry/fsimpl/host/inode_refs.go
+++ b/pkg/sentry/fsimpl/host/inode_refs.go
@@ -1,12 +1,12 @@
 package host
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/kernfs/dentry_refs.go b/pkg/sentry/fsimpl/kernfs/dentry_refs.go
index dd5325635..b7125caee 100644
--- a/pkg/sentry/fsimpl/kernfs/dentry_refs.go
+++ b/pkg/sentry/fsimpl/kernfs/dentry_refs.go
@@ -1,12 +1,12 @@
 package kernfs
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/kernfs/static_directory_refs.go b/pkg/sentry/fsimpl/kernfs/static_directory_refs.go
index 80513f6aa..0ff013c97 100644
--- a/pkg/sentry/fsimpl/kernfs/static_directory_refs.go
+++ b/pkg/sentry/fsimpl/kernfs/static_directory_refs.go
@@ -1,12 +1,12 @@
 package kernfs
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/proc/fd_dir_inode_refs.go b/pkg/sentry/fsimpl/proc/fd_dir_inode_refs.go
index 8ed286c46..454862d98 100644
--- a/pkg/sentry/fsimpl/proc/fd_dir_inode_refs.go
+++ b/pkg/sentry/fsimpl/proc/fd_dir_inode_refs.go
@@ -1,12 +1,12 @@
 package proc
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/proc/fd_info_dir_inode_refs.go b/pkg/sentry/fsimpl/proc/fd_info_dir_inode_refs.go
index 957c6a6dd..d2169be5b 100644
--- a/pkg/sentry/fsimpl/proc/fd_info_dir_inode_refs.go
+++ b/pkg/sentry/fsimpl/proc/fd_info_dir_inode_refs.go
@@ -1,12 +1,12 @@
 package proc
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/proc/subtasks_inode_refs.go b/pkg/sentry/fsimpl/proc/subtasks_inode_refs.go
index a80ec9e0a..9b50f632c 100644
--- a/pkg/sentry/fsimpl/proc/subtasks_inode_refs.go
+++ b/pkg/sentry/fsimpl/proc/subtasks_inode_refs.go
@@ -1,12 +1,12 @@
 package proc
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/proc/task_inode_refs.go b/pkg/sentry/fsimpl/proc/task_inode_refs.go
index c4835cbca..c29272f9b 100644
--- a/pkg/sentry/fsimpl/proc/task_inode_refs.go
+++ b/pkg/sentry/fsimpl/proc/task_inode_refs.go
@@ -1,12 +1,12 @@
 package proc
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/proc/tasks_inode_refs.go b/pkg/sentry/fsimpl/proc/tasks_inode_refs.go
index 5dfb34238..7e0b70f6c 100644
--- a/pkg/sentry/fsimpl/proc/tasks_inode_refs.go
+++ b/pkg/sentry/fsimpl/proc/tasks_inode_refs.go
@@ -1,12 +1,12 @@
 package proc
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/sys/dir_refs.go b/pkg/sentry/fsimpl/sys/dir_refs.go
index c05154e2b..d42edb20e 100644
--- a/pkg/sentry/fsimpl/sys/dir_refs.go
+++ b/pkg/sentry/fsimpl/sys/dir_refs.go
@@ -1,12 +1,12 @@
 package sys
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/tmpfs/inode_refs.go b/pkg/sentry/fsimpl/tmpfs/inode_refs.go
index 38cc30981..4f4037adb 100644
--- a/pkg/sentry/fsimpl/tmpfs/inode_refs.go
+++ b/pkg/sentry/fsimpl/tmpfs/inode_refs.go
@@ -1,12 +1,12 @@
 package tmpfs
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/kernel/fd_table_refs.go b/pkg/sentry/kernel/fd_table_refs.go
index 8973cac8a..dc7f4e246 100644
--- a/pkg/sentry/kernel/fd_table_refs.go
+++ b/pkg/sentry/kernel/fd_table_refs.go
@@ -1,12 +1,12 @@
 package kernel
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/kernel/fs_context_refs.go b/pkg/sentry/kernel/fs_context_refs.go
index c0e01dbb3..be045c862 100644
--- a/pkg/sentry/kernel/fs_context_refs.go
+++ b/pkg/sentry/kernel/fs_context_refs.go
@@ -1,12 +1,12 @@
 package kernel
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/kernel/process_group_refs.go b/pkg/sentry/kernel/process_group_refs.go
index 5ff83ab96..4622687b1 100644
--- a/pkg/sentry/kernel/process_group_refs.go
+++ b/pkg/sentry/kernel/process_group_refs.go
@@ -1,12 +1,12 @@
 package kernel
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/kernel/session_refs.go b/pkg/sentry/kernel/session_refs.go
index 9c51eda6c..89e43ae6b 100644
--- a/pkg/sentry/kernel/session_refs.go
+++ b/pkg/sentry/kernel/session_refs.go
@@ -1,12 +1,12 @@
 package kernel
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/kernel/shm/shm_refs.go b/pkg/sentry/kernel/shm/shm_refs.go
index 0da23fa5f..2b4f608c7 100644
--- a/pkg/sentry/kernel/shm/shm_refs.go
+++ b/pkg/sentry/kernel/shm/shm_refs.go
@@ -1,12 +1,12 @@
 package shm
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/mm/aio_mappable_refs.go b/pkg/sentry/mm/aio_mappable_refs.go
index c80c56d94..ac7690d3f 100644
--- a/pkg/sentry/mm/aio_mappable_refs.go
+++ b/pkg/sentry/mm/aio_mappable_refs.go
@@ -1,12 +1,12 @@
 package mm
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/mm/special_mappable_refs.go b/pkg/sentry/mm/special_mappable_refs.go
index 5eb7e69e0..b304fd2ef 100644
--- a/pkg/sentry/mm/special_mappable_refs.go
+++ b/pkg/sentry/mm/special_mappable_refs.go
@@ -1,12 +1,12 @@
 package mm
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/platform/ring0/defs_impl_arm64.go b/pkg/sentry/platform/ring0/defs_impl_arm64.go
index 424b66f76..9fb351879 100644
--- a/pkg/sentry/platform/ring0/defs_impl_arm64.go
+++ b/pkg/sentry/platform/ring0/defs_impl_arm64.go
@@ -1,10 +1,9 @@
 package ring0
 
 import (
+	"fmt"
 	"gvisor.dev/gvisor/pkg/sentry/arch"
 	"gvisor.dev/gvisor/pkg/sentry/platform/ring0/pagetables"
-
-	"fmt"
 	"gvisor.dev/gvisor/pkg/usermem"
 	"io"
 	"reflect"
diff --git a/pkg/sentry/socket/unix/socket_refs.go b/pkg/sentry/socket/unix/socket_refs.go
index 680ea06cd..69fa54964 100644
--- a/pkg/sentry/socket/unix/socket_refs.go
+++ b/pkg/sentry/socket/unix/socket_refs.go
@@ -1,12 +1,12 @@
 package unix
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/socket/unix/transport/queue_refs.go b/pkg/sentry/socket/unix/transport/queue_refs.go
index 17951eb2f..a154c8334 100644
--- a/pkg/sentry/socket/unix/transport/queue_refs.go
+++ b/pkg/sentry/socket/unix/transport/queue_refs.go
@@ -1,12 +1,12 @@
 package transport
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/vfs/file_description_refs.go b/pkg/sentry/vfs/file_description_refs.go
index 5e612d7f0..3953d2396 100644
--- a/pkg/sentry/vfs/file_description_refs.go
+++ b/pkg/sentry/vfs/file_description_refs.go
@@ -1,12 +1,12 @@
 package vfs
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/vfs/filesystem_refs.go b/pkg/sentry/vfs/filesystem_refs.go
index aaa753c43..c6a390430 100644
--- a/pkg/sentry/vfs/filesystem_refs.go
+++ b/pkg/sentry/vfs/filesystem_refs.go
@@ -1,12 +1,12 @@
 package vfs
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/vfs/mount_namespace_refs.go b/pkg/sentry/vfs/mount_namespace_refs.go
index 56b8d9903..ed126cc5e 100644
--- a/pkg/sentry/vfs/mount_namespace_refs.go
+++ b/pkg/sentry/vfs/mount_namespace_refs.go
@@ -1,12 +1,12 @@
 package vfs
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/tcpip/link/tun/tun_endpoint_refs.go b/pkg/tcpip/link/tun/tun_endpoint_refs.go
index 7f80b1fa3..895a577ce 100644
--- a/pkg/tcpip/link/tun/tun_endpoint_refs.go
+++ b/pkg/tcpip/link/tun/tun_endpoint_refs.go
@@ -1,12 +1,12 @@
 package tun
 
 import (
-	"fmt"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so