3 files changed, 26 insertions, 27 deletions
diff --git a/pkg/sentry/fs/host/BUILD b/pkg/sentry/fs/host/BUILD
index d41d23a43..42a6c41c2 100644
--- a/pkg/sentry/fs/host/BUILD
+++ b/pkg/sentry/fs/host/BUILD
@@ -55,6 +55,7 @@ go_library(
         "//pkg/unet",
         "//pkg/usermem",
         "//pkg/waiter",
+        "//tools/go_marshal/primitive",
     ],
 )
 
diff --git a/pkg/sentry/fs/host/tty.go b/pkg/sentry/fs/host/tty.go
index e29ae00f2..67a807f9d 100644
--- a/pkg/sentry/fs/host/tty.go
+++ b/pkg/sentry/fs/host/tty.go
@@ -24,6 +24,7 @@ import (
 	"gvisor.dev/gvisor/pkg/sync"
 	"gvisor.dev/gvisor/pkg/syserror"
 	"gvisor.dev/gvisor/pkg/usermem"
+	"gvisor.dev/gvisor/tools/go_marshal/primitive"
 )
 
 // LINT.IfChange
@@ -123,6 +124,11 @@ func (t *TTYFileOperations) Release(ctx context.Context) {
 
 // Ioctl implements fs.FileOperations.Ioctl.
 func (t *TTYFileOperations) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO, args arch.SyscallArguments) (uintptr, error) {
+	task := kernel.TaskFromContext(ctx)
+	if task == nil {
+		return 0, syserror.ENOTTY
+	}
+
 	// Ignore arg[0].  This is the real FD:
 	fd := t.fileOperations.iops.fileState.FD()
 	ioctl := args[1].Uint64()
@@ -132,9 +138,7 @@ func (t *TTYFileOperations) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO
 		if err != nil {
 			return 0, err
 		}
-		_, err = usermem.CopyObjectOut(ctx, io, args[2].Pointer(), termios, usermem.IOOpts{
-			AddressSpaceActive: true,
-		})
+		_, err = termios.CopyOut(task, args[2].Pointer())
 		return 0, err
 
 	case linux.TCSETS, linux.TCSETSW, linux.TCSETSF:
@@ -146,9 +150,7 @@ func (t *TTYFileOperations) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO
 		}
 
 		var termios linux.Termios
-		if _, err := usermem.CopyObjectIn(ctx, io, args[2].Pointer(), &termios, usermem.IOOpts{
-			AddressSpaceActive: true,
-		}); err != nil {
+		if _, err := termios.CopyIn(task, args[2].Pointer()); err != nil {
 			return 0, err
 		}
 		err := ioctlSetTermios(fd, ioctl, &termios)
@@ -173,10 +175,8 @@ func (t *TTYFileOperations) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO
 
 		// Map the ProcessGroup into a ProcessGroupID in the task's PID
 		// namespace.
-		pgID := pidns.IDOfProcessGroup(t.fgProcessGroup)
-		_, err := usermem.CopyObjectOut(ctx, io, args[2].Pointer(), &pgID, usermem.IOOpts{
-			AddressSpaceActive: true,
-		})
+		pgID := primitive.Int32(pidns.IDOfProcessGroup(t.fgProcessGroup))
+		_, err := pgID.CopyOut(task, args[2].Pointer())
 		return 0, err
 
 	case linux.TIOCSPGRP:
@@ -184,11 +184,6 @@ func (t *TTYFileOperations) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO
 		// Equivalent to tcsetpgrp(fd, *argp).
 		// Set the foreground process group ID of this terminal.
 
-		task := kernel.TaskFromContext(ctx)
-		if task == nil {
-			return 0, syserror.ENOTTY
-		}
-
 		t.mu.Lock()
 		defer t.mu.Unlock()
 
@@ -208,12 +203,11 @@ func (t *TTYFileOperations) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO
 			return 0, syserror.ENOTTY
 		}
 
-		var pgID kernel.ProcessGroupID
-		if _, err := usermem.CopyObjectIn(ctx, io, args[2].Pointer(), &pgID, usermem.IOOpts{
-			AddressSpaceActive: true,
-		}); err != nil {
+		var pgIDP primitive.Int32
+		if _, err := pgIDP.CopyIn(task, args[2].Pointer()); err != nil {
 			return 0, err
 		}
+		pgID := kernel.ProcessGroupID(pgIDP)
 
 		// pgID must be non-negative.
 		if pgID < 0 {
@@ -242,9 +236,7 @@ func (t *TTYFileOperations) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO
 		if err != nil {
 			return 0, err
 		}
-		_, err = usermem.CopyObjectOut(ctx, io, args[2].Pointer(), winsize, usermem.IOOpts{
-			AddressSpaceActive: true,
-		})
+		_, err = winsize.CopyOut(task, args[2].Pointer())
 		return 0, err
 
 	case linux.TIOCSWINSZ:
@@ -255,9 +247,7 @@ func (t *TTYFileOperations) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO
 		// background ones) can set the winsize.
 
 		var winsize linux.Winsize
-		if _, err := usermem.CopyObjectIn(ctx, io, args[2].Pointer(), &winsize, usermem.IOOpts{
-			AddressSpaceActive: true,
-		}); err != nil {
+		if _, err := winsize.CopyIn(task, args[2].Pointer()); err != nil {
 			return 0, err
 		}
 		err := ioctlSetWinsize(fd, &winsize)
diff --git a/pkg/sentry/fs/tmpfs/tmpfs.go b/pkg/sentry/fs/tmpfs/tmpfs.go
index b095312fe..998b697ca 100644
--- a/pkg/sentry/fs/tmpfs/tmpfs.go
+++ b/pkg/sentry/fs/tmpfs/tmpfs.go
@@ -16,6 +16,8 @@
 package tmpfs
 
 import (
+	"math"
+
 	"gvisor.dev/gvisor/pkg/abi/linux"
 	"gvisor.dev/gvisor/pkg/context"
 	"gvisor.dev/gvisor/pkg/sentry/fs"
@@ -32,9 +34,15 @@ import (
 var fsInfo = fs.Info{
 	Type: linux.TMPFS_MAGIC,
 
+	// tmpfs currently does not support configurable size limits. In Linux,
+	// such a tmpfs mount will return f_blocks == f_bfree == f_bavail == 0 from
+	// statfs(2). However, many applications treat this as having a size limit
+	// of 0. To work around this, claim to have a very large but non-zero size,
+	// chosen to ensure that BlockSize * Blocks does not overflow int64 (which
+	// applications may also handle incorrectly).
 	// TODO(b/29637826): allow configuring a tmpfs size and enforce it.
-	TotalBlocks: 0,
-	FreeBlocks:  0,
+	TotalBlocks: math.MaxInt64 / usermem.PageSize,
+	FreeBlocks:  math.MaxInt64 / usermem.PageSize,
 }
 
 // rename implements fs.InodeOperations.Rename for tmpfs nodes.