9 files changed, 18 insertions, 7 deletions
diff --git a/pkg/sentry/fs/dev/null.go b/pkg/sentry/fs/dev/null.go
index 18dd08515..4404b97ef 100644
--- a/pkg/sentry/fs/dev/null.go
+++ b/pkg/sentry/fs/dev/null.go
@@ -97,6 +97,7 @@ func newZeroDevice(ctx context.Context, owner fs.FileOwner, mode linux.FileMode)
 func (zd *zeroDevice) GetFile(ctx context.Context, dirent *fs.Dirent, flags fs.FileFlags) (*fs.File, error) {
 	flags.Pread = true
 	flags.Pwrite = true
+	flags.NonSeekable = true
 
 	return fs.NewFile(ctx, dirent, flags, &zeroFileOperations{}), nil
 }
diff --git a/pkg/sentry/fs/file.go b/pkg/sentry/fs/file.go
index 6df7d7b4f..55ffe6c0c 100644
--- a/pkg/sentry/fs/file.go
+++ b/pkg/sentry/fs/file.go
@@ -267,7 +267,7 @@ func (f *File) Readv(ctx context.Context, dst usermem.IOSequence) (int64, error)
 
 	reads.Increment()
 	n, err := f.FileOperations.Read(ctx, f, dst, f.offset)
-	if n > 0 {
+	if n > 0 && !f.flags.NonSeekable {
 		atomic.AddInt64(&f.offset, n)
 	}
 	f.mu.Unlock()
@@ -330,7 +330,7 @@ func (f *File) Writev(ctx context.Context, src usermem.IOSequence) (int64, error
 
 	// We must hold the lock during the write.
 	n, err := f.FileOperations.Write(ctx, f, src, f.offset)
-	if n >= 0 {
+	if n >= 0 && !f.flags.NonSeekable {
 		atomic.StoreInt64(&f.offset, f.offset+n)
 	}
 	f.mu.Unlock()
diff --git a/pkg/sentry/fs/flags.go b/pkg/sentry/fs/flags.go
index f31bfa0db..1278f9c78 100644
--- a/pkg/sentry/fs/flags.go
+++ b/pkg/sentry/fs/flags.go
@@ -57,6 +57,9 @@ type FileFlags struct {
 	// Linux sets this flag for all files. Since gVisor is only compatible
 	// with 64-bit Linux, it also sets this flag for all files.
 	LargeFile bool
+
+	// NonSeekable indicates that file.offset isn't used.
+	NonSeekable bool
 }
 
 // SettableFileFlags is a subset of FileFlags above that can be changed
diff --git a/pkg/sentry/kernel/pipe/pipe.go b/pkg/sentry/kernel/pipe/pipe.go
index 755326d59..8e49070a9 100644
--- a/pkg/sentry/kernel/pipe/pipe.go
+++ b/pkg/sentry/kernel/pipe/pipe.go
@@ -162,6 +162,7 @@ func NewConnectedPipe(ctx context.Context, sizeBytes, atomicIOBytes int64) (*fs.
 //
 // Precondition: at least one of flags.Read or flags.Write must be set.
 func (p *Pipe) Open(ctx context.Context, d *fs.Dirent, flags fs.FileFlags) *fs.File {
+	flags.NonSeekable = true
 	switch {
 	case flags.Read && flags.Write:
 		p.rOpen()
diff --git a/pkg/sentry/socket/epsocket/epsocket.go b/pkg/sentry/socket/epsocket/epsocket.go
index a42cf4caf..8e65e1b3f 100644
--- a/pkg/sentry/socket/epsocket/epsocket.go
+++ b/pkg/sentry/socket/epsocket/epsocket.go
@@ -262,7 +262,7 @@ func New(t *kernel.Task, family int, skType linux.SockType, protocol int, queue
 
 	dirent := socket.NewDirent(t, epsocketDevice)
 	defer dirent.DecRef()
-	return fs.NewFile(t, dirent, fs.FileFlags{Read: true, Write: true}, &SocketOperations{
+	return fs.NewFile(t, dirent, fs.FileFlags{Read: true, Write: true, NonSeekable: true}, &SocketOperations{
 		Queue:    queue,
 		family:   family,
 		Endpoint: endpoint,
diff --git a/pkg/sentry/socket/hostinet/socket.go b/pkg/sentry/socket/hostinet/socket.go
index cef007aca..c63f3aacf 100644
--- a/pkg/sentry/socket/hostinet/socket.go
+++ b/pkg/sentry/socket/hostinet/socket.go
@@ -77,7 +77,7 @@ func newSocketFile(ctx context.Context, family int, stype linux.SockType, protoc
 	}
 	dirent := socket.NewDirent(ctx, socketDevice)
 	defer dirent.DecRef()
-	return fs.NewFile(ctx, dirent, fs.FileFlags{NonBlocking: nonblock, Read: true, Write: true}, s), nil
+	return fs.NewFile(ctx, dirent, fs.FileFlags{NonBlocking: nonblock, Read: true, Write: true, NonSeekable: true}, s), nil
 }
 
 // Release implements fs.FileOperations.Release.
diff --git a/pkg/sentry/socket/netlink/provider.go b/pkg/sentry/socket/netlink/provider.go
index 31d2ca494..689cad997 100644
--- a/pkg/sentry/socket/netlink/provider.go
+++ b/pkg/sentry/socket/netlink/provider.go
@@ -89,7 +89,7 @@ func (*socketProvider) Socket(t *kernel.Task, stype linux.SockType, protocol int
 
 	d := socket.NewDirent(t, netlinkSocketDevice)
 	defer d.DecRef()
-	return fs.NewFile(t, d, fs.FileFlags{Read: true, Write: true}, s), nil
+	return fs.NewFile(t, d, fs.FileFlags{Read: true, Write: true, NonSeekable: true}, s), nil
 }
 
 // Pair implements socket.Provider.Pair by returning an error.
diff --git a/pkg/sentry/socket/rpcinet/socket.go b/pkg/sentry/socket/rpcinet/socket.go
index ba33eb671..c76b48ead 100644
--- a/pkg/sentry/socket/rpcinet/socket.go
+++ b/pkg/sentry/socket/rpcinet/socket.go
@@ -322,7 +322,13 @@ func (s *socketOperations) Accept(t *kernel.Task, peerRequested bool, flags int,
 
 	dirent := socket.NewDirent(t, socketDevice)
 	defer dirent.DecRef()
-	file := fs.NewFile(t, dirent, fs.FileFlags{Read: true, Write: true, NonBlocking: flags&linux.SOCK_NONBLOCK != 0}, &socketOperations{
+	fileFlags := fs.FileFlags{
+		Read:        true,
+		Write:       true,
+		NonSeekable: true,
+		NonBlocking: flags&linux.SOCK_NONBLOCK != 0,
+	}
+	file := fs.NewFile(t, dirent, fileFlags, &socketOperations{
 		wq:       &wq,
 		fd:       payload.Fd,
 		rpcConn:  s.rpcConn,
diff --git a/pkg/sentry/socket/unix/unix.go b/pkg/sentry/socket/unix/unix.go
index 97db87f3e..5fc43db8c 100644
--- a/pkg/sentry/socket/unix/unix.go
+++ b/pkg/sentry/socket/unix/unix.go
@@ -64,7 +64,7 @@ type SocketOperations struct {
 func New(ctx context.Context, endpoint transport.Endpoint, stype linux.SockType) *fs.File {
 	dirent := socket.NewDirent(ctx, unixSocketDevice)
 	defer dirent.DecRef()
-	return NewWithDirent(ctx, dirent, endpoint, stype, fs.FileFlags{Read: true, Write: true})
+	return NewWithDirent(ctx, dirent, endpoint, stype, fs.FileFlags{Read: true, Write: true, NonSeekable: true})
 }
 
 // NewWithDirent creates a new unix socket using an existing dirent.