From d201feb8c5e425bfa8abc905f24d49b268520aec Mon Sep 17 00:00:00 2001
From: Rahat Mahmood <rahat@google.com>
Date: Tue, 15 Sep 2020 23:37:04 -0700
Subject: Enable automated marshalling for the syscall package.

PiperOrigin-RevId: 331940975
---
 pkg/sentry/kernel/BUILD           |  2 ++
 pkg/sentry/kernel/auth/BUILD      |  1 +
 pkg/sentry/kernel/auth/id.go      |  4 ++++
 pkg/sentry/kernel/ptrace.go       | 23 +++++++++++-----------
 pkg/sentry/kernel/ptrace_amd64.go |  2 +-
 pkg/sentry/kernel/task_clone.go   |  6 +++---
 pkg/sentry/kernel/task_exit.go    |  3 ++-
 pkg/sentry/kernel/task_futex.go   |  7 ++++---
 pkg/sentry/kernel/task_run.go     |  2 +-
 pkg/sentry/kernel/task_syscall.go |  7 ++++---
 pkg/sentry/kernel/task_usermem.go | 40 +++++++++------------------------------
 pkg/sentry/kernel/threads.go      |  2 ++
 12 files changed, 44 insertions(+), 55 deletions(-)

(limited to 'pkg/sentry/kernel')

diff --git a/pkg/sentry/kernel/BUILD b/pkg/sentry/kernel/BUILD
index 66cf4f207..a43c549f1 100644
--- a/pkg/sentry/kernel/BUILD
+++ b/pkg/sentry/kernel/BUILD
@@ -197,6 +197,7 @@ go_library(
         "gvisor.dev/gvisor/pkg/sentry/device",
         "gvisor.dev/gvisor/pkg/tcpip",
     ],
+    marshal = True,
     visibility = ["//:sandbox"],
     deps = [
         ":uncaught_signal_go_proto",
@@ -213,6 +214,7 @@ go_library(
         "//pkg/fspath",
         "//pkg/log",
         "//pkg/marshal",
+        "//pkg/marshal/primitive",
         "//pkg/metric",
         "//pkg/refs",
         "//pkg/refs_vfs2",
diff --git a/pkg/sentry/kernel/auth/BUILD b/pkg/sentry/kernel/auth/BUILD
index 2bc49483a..869e49ebc 100644
--- a/pkg/sentry/kernel/auth/BUILD
+++ b/pkg/sentry/kernel/auth/BUILD
@@ -57,6 +57,7 @@ go_library(
         "id_map_set.go",
         "user_namespace.go",
     ],
+    marshal = True,
     visibility = ["//pkg/sentry:internal"],
     deps = [
         "//pkg/abi/linux",
diff --git a/pkg/sentry/kernel/auth/id.go b/pkg/sentry/kernel/auth/id.go
index 0a58ba17c..4c32ee703 100644
--- a/pkg/sentry/kernel/auth/id.go
+++ b/pkg/sentry/kernel/auth/id.go
@@ -19,9 +19,13 @@ import (
 )
 
 // UID is a user ID in an unspecified user namespace.
+//
+// +marshal
 type UID uint32
 
 // GID is a group ID in an unspecified user namespace.
+//
+// +marshal slice:GIDSlice
 type GID uint32
 
 // In the root user namespace, user/group IDs have a 1-to-1 relationship with
diff --git a/pkg/sentry/kernel/ptrace.go b/pkg/sentry/kernel/ptrace.go
index 50df179c3..1145faf13 100644
--- a/pkg/sentry/kernel/ptrace.go
+++ b/pkg/sentry/kernel/ptrace.go
@@ -18,6 +18,7 @@ import (
 	"fmt"
 
 	"gvisor.dev/gvisor/pkg/abi/linux"
+	"gvisor.dev/gvisor/pkg/marshal/primitive"
 	"gvisor.dev/gvisor/pkg/sentry/arch"
 	"gvisor.dev/gvisor/pkg/sentry/mm"
 	"gvisor.dev/gvisor/pkg/syserror"
@@ -999,18 +1000,15 @@ func (t *Task) Ptrace(req int64, pid ThreadID, addr, data usermem.Addr) error {
 		// at the address specified by the data parameter, and the return value
 		// is the error flag." - ptrace(2)
 		word := t.Arch().Native(0)
-		if _, err := usermem.CopyObjectIn(t, target.MemoryManager(), addr, word, usermem.IOOpts{
-			IgnorePermissions: true,
-		}); err != nil {
+		if _, err := word.CopyIn(target.AsCopyContext(usermem.IOOpts{IgnorePermissions: true}), addr); err != nil {
 			return err
 		}
-		_, err := t.CopyOut(data, word)
+		_, err := word.CopyOut(t, data)
 		return err
 
 	case linux.PTRACE_POKETEXT, linux.PTRACE_POKEDATA:
-		_, err := usermem.CopyObjectOut(t, target.MemoryManager(), addr, t.Arch().Native(uintptr(data)), usermem.IOOpts{
-			IgnorePermissions: true,
-		})
+		word := t.Arch().Native(uintptr(data))
+		_, err := word.CopyOut(target.AsCopyContext(usermem.IOOpts{IgnorePermissions: true}), addr)
 		return err
 
 	case linux.PTRACE_GETREGSET:
@@ -1078,12 +1076,12 @@ func (t *Task) Ptrace(req int64, pid ThreadID, addr, data usermem.Addr) error {
 		if target.ptraceSiginfo == nil {
 			return syserror.EINVAL
 		}
-		_, err := t.CopyOut(data, target.ptraceSiginfo)
+		_, err := target.ptraceSiginfo.CopyOut(t, data)
 		return err
 
 	case linux.PTRACE_SETSIGINFO:
 		var info arch.SignalInfo
-		if _, err := t.CopyIn(data, &info); err != nil {
+		if _, err := info.CopyIn(t, data); err != nil {
 			return err
 		}
 		t.tg.pidns.owner.mu.RLock()
@@ -1098,7 +1096,8 @@ func (t *Task) Ptrace(req int64, pid ThreadID, addr, data usermem.Addr) error {
 		if addr != linux.SignalSetSize {
 			return syserror.EINVAL
 		}
-		_, err := t.CopyOut(data, target.SignalMask())
+		mask := target.SignalMask()
+		_, err := mask.CopyOut(t, data)
 		return err
 
 	case linux.PTRACE_SETSIGMASK:
@@ -1106,7 +1105,7 @@ func (t *Task) Ptrace(req int64, pid ThreadID, addr, data usermem.Addr) error {
 			return syserror.EINVAL
 		}
 		var mask linux.SignalSet
-		if _, err := t.CopyIn(data, &mask); err != nil {
+		if _, err := mask.CopyIn(t, data); err != nil {
 			return err
 		}
 		// The target's task goroutine is stopped, so this is safe:
@@ -1121,7 +1120,7 @@ func (t *Task) Ptrace(req int64, pid ThreadID, addr, data usermem.Addr) error {
 	case linux.PTRACE_GETEVENTMSG:
 		t.tg.pidns.owner.mu.RLock()
 		defer t.tg.pidns.owner.mu.RUnlock()
-		_, err := t.CopyOut(usermem.Addr(data), target.ptraceEventMsg)
+		_, err := primitive.CopyUint64Out(t, usermem.Addr(data), target.ptraceEventMsg)
 		return err
 
 	// PEEKSIGINFO is unimplemented but seems to have no users anywhere.
diff --git a/pkg/sentry/kernel/ptrace_amd64.go b/pkg/sentry/kernel/ptrace_amd64.go
index cef1276ec..609ad3941 100644
--- a/pkg/sentry/kernel/ptrace_amd64.go
+++ b/pkg/sentry/kernel/ptrace_amd64.go
@@ -30,7 +30,7 @@ func (t *Task) ptraceArch(target *Task, req int64, addr, data usermem.Addr) erro
 		if err != nil {
 			return err
 		}
-		_, err = t.CopyOut(data, n)
+		_, err = n.CopyOut(t, data)
 		return err
 
 	case linux.PTRACE_POKEUSR: // aka PTRACE_POKEUSER
diff --git a/pkg/sentry/kernel/task_clone.go b/pkg/sentry/kernel/task_clone.go
index 9d7a9128f..fce1064a7 100644
--- a/pkg/sentry/kernel/task_clone.go
+++ b/pkg/sentry/kernel/task_clone.go
@@ -341,12 +341,12 @@ func (t *Task) Clone(opts *CloneOptions) (ThreadID, *SyscallControl, error) {
 		nt.SetClearTID(opts.ChildTID)
 	}
 	if opts.ChildSetTID {
-		// Can't use Task.CopyOut, which assumes AddressSpaceActive.
-		usermem.CopyObjectOut(t, nt.MemoryManager(), opts.ChildTID, nt.ThreadID(), usermem.IOOpts{})
+		ctid := nt.ThreadID()
+		ctid.CopyOut(nt.AsCopyContext(usermem.IOOpts{AddressSpaceActive: false}), opts.ChildTID)
 	}
 	ntid := t.tg.pidns.IDOfTask(nt)
 	if opts.ParentSetTID {
-		t.CopyOut(opts.ParentTID, ntid)
+		ntid.CopyOut(t, opts.ParentTID)
 	}
 
 	kind := ptraceCloneKindClone
diff --git a/pkg/sentry/kernel/task_exit.go b/pkg/sentry/kernel/task_exit.go
index b76f7f503..b400a8b41 100644
--- a/pkg/sentry/kernel/task_exit.go
+++ b/pkg/sentry/kernel/task_exit.go
@@ -248,7 +248,8 @@ func (*runExitMain) execute(t *Task) taskRunState {
 		signaled := t.tg.exiting && t.tg.exitStatus.Signaled()
 		t.tg.signalHandlers.mu.Unlock()
 		if !signaled {
-			if _, err := t.CopyOut(t.cleartid, ThreadID(0)); err == nil {
+			zero := ThreadID(0)
+			if _, err := zero.CopyOut(t, t.cleartid); err == nil {
 				t.Futex().Wake(t, t.cleartid, false, ^uint32(0), 1)
 			}
 			// If the CopyOut fails, there's nothing we can do.
diff --git a/pkg/sentry/kernel/task_futex.go b/pkg/sentry/kernel/task_futex.go
index 4b535c949..c80391475 100644
--- a/pkg/sentry/kernel/task_futex.go
+++ b/pkg/sentry/kernel/task_futex.go
@@ -16,6 +16,7 @@ package kernel
 
 import (
 	"gvisor.dev/gvisor/pkg/abi/linux"
+	"gvisor.dev/gvisor/pkg/marshal/primitive"
 	"gvisor.dev/gvisor/pkg/sentry/kernel/futex"
 	"gvisor.dev/gvisor/pkg/usermem"
 )
@@ -87,7 +88,7 @@ func (t *Task) exitRobustList() {
 		return
 	}
 
-	next := rl.List
+	next := primitive.Uint64(rl.List)
 	done := 0
 	var pendingLockAddr usermem.Addr
 	if rl.ListOpPending != 0 {
@@ -99,12 +100,12 @@ func (t *Task) exitRobustList() {
 		// We traverse to the next element of the list before we
 		// actually wake anything. This prevents the race where waking
 		// this futex causes a modification of the list.
-		thisLockAddr := usermem.Addr(next + rl.FutexOffset)
+		thisLockAddr := usermem.Addr(uint64(next) + rl.FutexOffset)
 
 		// Try to decode the next element in the list before waking the
 		// current futex. But don't check the error until after we've
 		// woken the current futex. Linux does it in this order too
-		_, nextErr := t.CopyIn(usermem.Addr(next), &next)
+		_, nextErr := next.CopyIn(t, usermem.Addr(next))
 
 		// Wakeup the current futex if it's not pending.
 		if thisLockAddr != pendingLockAddr {
diff --git a/pkg/sentry/kernel/task_run.go b/pkg/sentry/kernel/task_run.go
index aa3a573c0..8dc3fec90 100644
--- a/pkg/sentry/kernel/task_run.go
+++ b/pkg/sentry/kernel/task_run.go
@@ -141,7 +141,7 @@ func (*runApp) handleCPUIDInstruction(t *Task) error {
 	region := trace.StartRegion(t.traceContext, cpuidRegion)
 	expected := arch.CPUIDInstruction[:]
 	found := make([]byte, len(expected))
-	_, err := t.CopyIn(usermem.Addr(t.Arch().IP()), &found)
+	_, err := t.CopyInBytes(usermem.Addr(t.Arch().IP()), found)
 	if err == nil && bytes.Equal(expected, found) {
 		// Skip the cpuid instruction.
 		t.Arch().CPUIDEmulate(t)
diff --git a/pkg/sentry/kernel/task_syscall.go b/pkg/sentry/kernel/task_syscall.go
index 2dbf86547..0141459e7 100644
--- a/pkg/sentry/kernel/task_syscall.go
+++ b/pkg/sentry/kernel/task_syscall.go
@@ -22,6 +22,7 @@ import (
 
 	"gvisor.dev/gvisor/pkg/abi/linux"
 	"gvisor.dev/gvisor/pkg/bits"
+	"gvisor.dev/gvisor/pkg/marshal"
 	"gvisor.dev/gvisor/pkg/metric"
 	"gvisor.dev/gvisor/pkg/sentry/arch"
 	"gvisor.dev/gvisor/pkg/sentry/memmap"
@@ -287,7 +288,7 @@ func (t *Task) doVsyscall(addr usermem.Addr, sysno uintptr) taskRunState {
 
 	// Grab the caller up front, to make sure there's a sensible stack.
 	caller := t.Arch().Native(uintptr(0))
-	if _, err := t.CopyIn(usermem.Addr(t.Arch().Stack()), caller); err != nil {
+	if _, err := caller.CopyIn(t, usermem.Addr(t.Arch().Stack())); err != nil {
 		t.Debugf("vsyscall %d: error reading return address from stack: %v", sysno, err)
 		t.forceSignal(linux.SIGSEGV, false /* unconditional */)
 		t.SendSignal(SignalInfoPriv(linux.SIGSEGV))
@@ -323,7 +324,7 @@ func (t *Task) doVsyscall(addr usermem.Addr, sysno uintptr) taskRunState {
 type runVsyscallAfterPtraceEventSeccomp struct {
 	addr   usermem.Addr
 	sysno  uintptr
-	caller interface{}
+	caller marshal.Marshallable
 }
 
 func (r *runVsyscallAfterPtraceEventSeccomp) execute(t *Task) taskRunState {
@@ -346,7 +347,7 @@ func (r *runVsyscallAfterPtraceEventSeccomp) execute(t *Task) taskRunState {
 	return t.doVsyscallInvoke(sysno, t.Arch().SyscallArgs(), r.caller)
 }
 
-func (t *Task) doVsyscallInvoke(sysno uintptr, args arch.SyscallArguments, caller interface{}) taskRunState {
+func (t *Task) doVsyscallInvoke(sysno uintptr, args arch.SyscallArguments, caller marshal.Marshallable) taskRunState {
 	rval, ctrl, err := t.executeSyscall(sysno, args)
 	if ctrl != nil {
 		t.Debugf("vsyscall %d, caller %x: syscall control: %v", sysno, t.Arch().Value(caller), ctrl)
diff --git a/pkg/sentry/kernel/task_usermem.go b/pkg/sentry/kernel/task_usermem.go
index 0cb86e390..14d765af1 100644
--- a/pkg/sentry/kernel/task_usermem.go
+++ b/pkg/sentry/kernel/task_usermem.go
@@ -43,17 +43,6 @@ func (t *Task) Deactivate() {
 	}
 }
 
-// CopyIn copies a fixed-size value or slice of fixed-size values in from the
-// task's memory. The copy will fail with syscall.EFAULT if it traverses user
-// memory that is unmapped or not readable by the user.
-//
-// This Task's AddressSpace must be active.
-func (t *Task) CopyIn(addr usermem.Addr, dst interface{}) (int, error) {
-	return usermem.CopyObjectIn(t, t.MemoryManager(), addr, dst, usermem.IOOpts{
-		AddressSpaceActive: true,
-	})
-}
-
 // CopyInBytes is a fast version of CopyIn if the caller can serialize the
 // data without reflection and pass in a byte slice.
 //
@@ -64,17 +53,6 @@ func (t *Task) CopyInBytes(addr usermem.Addr, dst []byte) (int, error) {
 	})
 }
 
-// CopyOut copies a fixed-size value or slice of fixed-size values out to the
-// task's memory. The copy will fail with syscall.EFAULT if it traverses user
-// memory that is unmapped or not writeable by the user.
-//
-// This Task's AddressSpace must be active.
-func (t *Task) CopyOut(addr usermem.Addr, src interface{}) (int, error) {
-	return usermem.CopyObjectOut(t, t.MemoryManager(), addr, src, usermem.IOOpts{
-		AddressSpaceActive: true,
-	})
-}
-
 // CopyOutBytes is a fast version of CopyOut if the caller can serialize the
 // data without reflection and pass in a byte slice.
 //
@@ -114,7 +92,7 @@ func (t *Task) CopyInVector(addr usermem.Addr, maxElemSize, maxTotalSize int) ([
 	var v []string
 	for {
 		argAddr := t.Arch().Native(0)
-		if _, err := t.CopyIn(addr, argAddr); err != nil {
+		if _, err := argAddr.CopyIn(t, addr); err != nil {
 			return v, err
 		}
 		if t.Arch().Value(argAddr) == 0 {
@@ -302,29 +280,29 @@ func (t *Task) IovecsIOSequence(addr usermem.Addr, iovcnt int, opts usermem.IOOp
 	}, nil
 }
 
-// CopyContextWithOpts wraps a task to allow copying memory to and from the
+// CopyContext wraps a task to allow copying memory to and from the
 // task memory with user specified usermem.IOOpts.
-type CopyContextWithOpts struct {
+type CopyContext struct {
 	*Task
 	opts usermem.IOOpts
 }
 
-// AsCopyContextWithOpts wraps the task and returns it as CopyContextWithOpts.
-func (t *Task) AsCopyContextWithOpts(opts usermem.IOOpts) *CopyContextWithOpts {
-	return &CopyContextWithOpts{t, opts}
+// AsCopyContext wraps the task and returns it as CopyContext.
+func (t *Task) AsCopyContext(opts usermem.IOOpts) *CopyContext {
+	return &CopyContext{t, opts}
 }
 
 // CopyInString copies a string in from the task's memory.
-func (t *CopyContextWithOpts) CopyInString(addr usermem.Addr, maxLen int) (string, error) {
+func (t *CopyContext) CopyInString(addr usermem.Addr, maxLen int) (string, error) {
 	return usermem.CopyStringIn(t, t.MemoryManager(), addr, maxLen, t.opts)
 }
 
 // CopyInBytes copies task memory into dst from an IO context.
-func (t *CopyContextWithOpts) CopyInBytes(addr usermem.Addr, dst []byte) (int, error) {
+func (t *CopyContext) CopyInBytes(addr usermem.Addr, dst []byte) (int, error) {
 	return t.MemoryManager().CopyIn(t, addr, dst, t.opts)
 }
 
 // CopyOutBytes copies src into task memoryfrom an IO context.
-func (t *CopyContextWithOpts) CopyOutBytes(addr usermem.Addr, src []byte) (int, error) {
+func (t *CopyContext) CopyOutBytes(addr usermem.Addr, src []byte) (int, error) {
 	return t.MemoryManager().CopyOut(t, addr, src, t.opts)
 }
diff --git a/pkg/sentry/kernel/threads.go b/pkg/sentry/kernel/threads.go
index 872e1a82d..5ae5906e8 100644
--- a/pkg/sentry/kernel/threads.go
+++ b/pkg/sentry/kernel/threads.go
@@ -36,6 +36,8 @@ import (
 const TasksLimit = (1 << 16)
 
 // ThreadID is a generic thread identifier.
+//
+// +marshal
 type ThreadID int32
 
 // String returns a decimal representation of the ThreadID.
-- 
cgit v1.2.3