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-rw-r--r--pkg/context/context.go4
-rw-r--r--pkg/eventchannel/event_test.go4
-rw-r--r--pkg/log/glog.go6
-rw-r--r--pkg/log/json.go2
-rw-r--r--pkg/log/json_k8s.go4
-rw-r--r--pkg/log/log.go2
-rw-r--r--pkg/log/log_test.go6
-rw-r--r--pkg/p9/client.go45
-rw-r--r--pkg/p9/client_test.go7
-rw-r--r--pkg/p9/transport_flipcall.go2
-rw-r--r--pkg/segment/test/segment_test.go2
-rw-r--r--pkg/sentry/arch/stack.go3
-rw-r--r--pkg/sentry/contexttest/contexttest.go4
-rw-r--r--pkg/sentry/fs/fdpipe/pipe_test.go4
-rw-r--r--pkg/sentry/fs/gofer/file_state.go1
-rw-r--r--pkg/sentry/fs/gofer/handles.go1
-rw-r--r--pkg/sentry/fs/gofer/inode.go2
-rw-r--r--pkg/sentry/fs/gofer/inode_state.go1
-rw-r--r--pkg/sentry/fs/gofer/session_state.go1
-rw-r--r--pkg/sentry/fs/host/socket_test.go6
-rw-r--r--pkg/sentry/fs/inode.go1
-rw-r--r--pkg/sentry/fs/proc/sys_net.go4
-rw-r--r--pkg/sentry/fsimpl/ext/filesystem.go4
-rw-r--r--pkg/sentry/fsimpl/gofer/filesystem.go12
-rw-r--r--pkg/sentry/fsimpl/gofer/gofer.go60
-rw-r--r--pkg/sentry/fsimpl/gofer/p9file.go14
-rw-r--r--pkg/sentry/fsimpl/kernfs/filesystem.go4
-rw-r--r--pkg/sentry/fsimpl/proc/task_net.go4
-rw-r--r--pkg/sentry/fsimpl/tmpfs/BUILD1
-rw-r--r--pkg/sentry/fsimpl/tmpfs/filesystem.go24
-rw-r--r--pkg/sentry/fsimpl/tmpfs/stat_test.go8
-rw-r--r--pkg/sentry/fsimpl/tmpfs/tmpfs.go77
-rw-r--r--pkg/sentry/kernel/fd_table.go55
-rw-r--r--pkg/sentry/kernel/shm/shm.go2
-rw-r--r--pkg/sentry/kernel/syscalls.go36
-rw-r--r--pkg/sentry/kernel/syscalls_state.go36
-rw-r--r--pkg/sentry/kernel/task.go9
-rw-r--r--pkg/sentry/kernel/task_context.go3
-rw-r--r--pkg/sentry/kernel/task_identity.go2
-rw-r--r--pkg/sentry/kernel/task_signals.go2
-rw-r--r--pkg/sentry/kernel/time/time.go10
-rw-r--r--pkg/sentry/platform/kvm/kvm_arm64.go4
-rw-r--r--pkg/sentry/platform/kvm/machine_arm64_unsafe.go63
-rw-r--r--pkg/sentry/platform/ring0/BUILD2
-rw-r--r--pkg/sentry/platform/ring0/lib_arm64.go7
-rw-r--r--pkg/sentry/platform/ring0/lib_arm64_unsafe.go108
-rw-r--r--pkg/sentry/strace/strace.go3
-rw-r--r--pkg/sentry/syscalls/linux/sys_prctl.go4
-rw-r--r--pkg/sentry/syscalls/linux/sys_socket.go9
-rw-r--r--pkg/sentry/syscalls/linux/vfs2/BUILD6
-rw-r--r--pkg/sentry/syscalls/linux/vfs2/getdents.go20
-rw-r--r--pkg/sentry/syscalls/linux/vfs2/linux64_override_amd64.go40
-rw-r--r--pkg/sentry/syscalls/linux/vfs2/socket.go1138
-rw-r--r--pkg/sentry/syscalls/linux/vfs2/xattr.go13
-rw-r--r--pkg/sentry/vfs/anonfs.go4
-rw-r--r--pkg/sentry/vfs/file_description.go32
-rw-r--r--pkg/sentry/vfs/file_description_impl_util.go4
-rw-r--r--pkg/sentry/vfs/filesystem.go24
-rw-r--r--pkg/sentry/vfs/memxattr/BUILD15
-rw-r--r--pkg/sentry/vfs/memxattr/xattr.go102
-rw-r--r--pkg/sentry/vfs/options.go14
-rw-r--r--pkg/sentry/vfs/vfs.go8
-rw-r--r--pkg/state/state.go5
-rw-r--r--pkg/tcpip/header/eth_test.go2
-rw-r--r--pkg/tcpip/header/ndp_test.go2
-rw-r--r--pkg/tcpip/link/fdbased/endpoint.go2
-rw-r--r--pkg/tcpip/network/arp/arp_test.go3
-rw-r--r--pkg/tcpip/stack/ndp_test.go18
-rw-r--r--pkg/tcpip/stack/stack_test.go32
-rw-r--r--pkg/tcpip/tcpip_test.go2
-rw-r--r--pkg/tcpip/transport/tcp/tcp_test.go4
-rw-r--r--pkg/tcpip/transport/tcp/testing/context/context.go9
-rw-r--r--pkg/tcpip/transport/udp/udp_test.go17
-rw-r--r--pkg/usermem/usermem.go3
74 files changed, 1894 insertions, 300 deletions
diff --git a/pkg/context/context.go b/pkg/context/context.go
index 23e009ef3..5319b6d8d 100644
--- a/pkg/context/context.go
+++ b/pkg/context/context.go
@@ -127,10 +127,6 @@ func (logContext) Value(key interface{}) interface{} {
var bgContext = &logContext{Logger: log.Log()}
// Background returns an empty context using the default logger.
-//
-// Users should be wary of using a Background context. Please tag any use with
-// FIXME(b/38173783) and a note to remove this use.
-//
// Generally, one should use the Task as their context when available, or avoid
// having to use a context in places where a Task is unavailable.
//
diff --git a/pkg/eventchannel/event_test.go b/pkg/eventchannel/event_test.go
index 7f41b4a27..43750360b 100644
--- a/pkg/eventchannel/event_test.go
+++ b/pkg/eventchannel/event_test.go
@@ -78,7 +78,7 @@ func TestMultiEmitter(t *testing.T) {
for _, name := range names {
m := testMessage{name: name}
if _, err := me.Emit(m); err != nil {
- t.Fatal("me.Emit(%v) failed: %v", m, err)
+ t.Fatalf("me.Emit(%v) failed: %v", m, err)
}
}
@@ -96,7 +96,7 @@ func TestMultiEmitter(t *testing.T) {
// Close multiEmitter.
if err := me.Close(); err != nil {
- t.Fatal("me.Close() failed: %v", err)
+ t.Fatalf("me.Close() failed: %v", err)
}
// All testEmitters should be closed.
diff --git a/pkg/log/glog.go b/pkg/log/glog.go
index b4f7bb5a4..f57c4427b 100644
--- a/pkg/log/glog.go
+++ b/pkg/log/glog.go
@@ -25,7 +25,7 @@ import (
// GoogleEmitter is a wrapper that emits logs in a format compatible with
// package github.com/golang/glog.
type GoogleEmitter struct {
- Writer
+ *Writer
}
// pid is used for the threadid component of the header.
@@ -46,7 +46,7 @@ var pid = os.Getpid()
// line The line number
// msg The user-supplied message
//
-func (g *GoogleEmitter) Emit(depth int, level Level, timestamp time.Time, format string, args ...interface{}) {
+func (g GoogleEmitter) Emit(depth int, level Level, timestamp time.Time, format string, args ...interface{}) {
// Log level.
prefix := byte('?')
switch level {
@@ -81,5 +81,5 @@ func (g *GoogleEmitter) Emit(depth int, level Level, timestamp time.Time, format
message := fmt.Sprintf(format, args...)
// Emit the formatted result.
- fmt.Fprintf(&g.Writer, "%c%02d%02d %02d:%02d:%02d.%06d % 7d %s:%d] %s\n", prefix, int(month), day, hour, minute, second, microsecond, pid, file, line, message)
+ fmt.Fprintf(g.Writer, "%c%02d%02d %02d:%02d:%02d.%06d % 7d %s:%d] %s\n", prefix, int(month), day, hour, minute, second, microsecond, pid, file, line, message)
}
diff --git a/pkg/log/json.go b/pkg/log/json.go
index 0943db1cc..bdf9d691e 100644
--- a/pkg/log/json.go
+++ b/pkg/log/json.go
@@ -58,7 +58,7 @@ func (lv *Level) UnmarshalJSON(b []byte) error {
// JSONEmitter logs messages in json format.
type JSONEmitter struct {
- Writer
+ *Writer
}
// Emit implements Emitter.Emit.
diff --git a/pkg/log/json_k8s.go b/pkg/log/json_k8s.go
index 6c6fc8b6f..5883e95e1 100644
--- a/pkg/log/json_k8s.go
+++ b/pkg/log/json_k8s.go
@@ -29,11 +29,11 @@ type k8sJSONLog struct {
// K8sJSONEmitter logs messages in json format that is compatible with
// Kubernetes fluent configuration.
type K8sJSONEmitter struct {
- Writer
+ *Writer
}
// Emit implements Emitter.Emit.
-func (e *K8sJSONEmitter) Emit(_ int, level Level, timestamp time.Time, format string, v ...interface{}) {
+func (e K8sJSONEmitter) Emit(_ int, level Level, timestamp time.Time, format string, v ...interface{}) {
j := k8sJSONLog{
Log: fmt.Sprintf(format, v...),
Level: level,
diff --git a/pkg/log/log.go b/pkg/log/log.go
index a794da1aa..37e0605ad 100644
--- a/pkg/log/log.go
+++ b/pkg/log/log.go
@@ -374,5 +374,5 @@ func CopyStandardLogTo(l Level) error {
func init() {
// Store the initial value for the log.
- log.Store(&BasicLogger{Level: Info, Emitter: &GoogleEmitter{Writer{Next: os.Stderr}}})
+ log.Store(&BasicLogger{Level: Info, Emitter: GoogleEmitter{&Writer{Next: os.Stderr}}})
}
diff --git a/pkg/log/log_test.go b/pkg/log/log_test.go
index 402cc29ae..9ff18559b 100644
--- a/pkg/log/log_test.go
+++ b/pkg/log/log_test.go
@@ -52,7 +52,7 @@ func TestDropMessages(t *testing.T) {
t.Fatalf("Write should have failed")
}
- fmt.Printf("writer: %+v\n", w)
+ fmt.Printf("writer: %#v\n", &w)
tw.fail = false
if _, err := w.Write([]byte("line 2\n")); err != nil {
@@ -76,7 +76,7 @@ func TestDropMessages(t *testing.T) {
func TestCaller(t *testing.T) {
tw := &testWriter{}
- e := &GoogleEmitter{Writer: Writer{Next: tw}}
+ e := GoogleEmitter{Writer: &Writer{Next: tw}}
bl := &BasicLogger{
Emitter: e,
Level: Debug,
@@ -94,7 +94,7 @@ func BenchmarkGoogleLogging(b *testing.B) {
tw := &testWriter{
limit: 1, // Only record one message.
}
- e := &GoogleEmitter{Writer: Writer{Next: tw}}
+ e := GoogleEmitter{Writer: &Writer{Next: tw}}
bl := &BasicLogger{
Emitter: e,
Level: Debug,
diff --git a/pkg/p9/client.go b/pkg/p9/client.go
index a6f493b82..71e944c30 100644
--- a/pkg/p9/client.go
+++ b/pkg/p9/client.go
@@ -174,7 +174,7 @@ func NewClient(socket *unet.Socket, messageSize uint32, version string) (*Client
// our sendRecv function to use that functionality. Otherwise,
// we stick to sendRecvLegacy.
rversion := Rversion{}
- err := c.sendRecvLegacy(&Tversion{
+ _, err := c.sendRecvLegacy(&Tversion{
Version: versionString(requested),
MSize: messageSize,
}, &rversion)
@@ -219,11 +219,11 @@ func NewClient(socket *unet.Socket, messageSize uint32, version string) (*Client
c.sendRecv = c.sendRecvChannel
} else {
// Channel setup failed; fallback.
- c.sendRecv = c.sendRecvLegacy
+ c.sendRecv = c.sendRecvLegacySyscallErr
}
} else {
// No channels available: use the legacy mechanism.
- c.sendRecv = c.sendRecvLegacy
+ c.sendRecv = c.sendRecvLegacySyscallErr
}
// Ensure that the socket and channels are closed when the socket is shut
@@ -305,7 +305,7 @@ func (c *Client) openChannel(id int) error {
)
// Open the data channel.
- if err := c.sendRecvLegacy(&Tchannel{
+ if _, err := c.sendRecvLegacy(&Tchannel{
ID: uint32(id),
Control: 0,
}, &rchannel0); err != nil {
@@ -319,7 +319,7 @@ func (c *Client) openChannel(id int) error {
defer rchannel0.FilePayload().Close()
// Open the channel for file descriptors.
- if err := c.sendRecvLegacy(&Tchannel{
+ if _, err := c.sendRecvLegacy(&Tchannel{
ID: uint32(id),
Control: 1,
}, &rchannel1); err != nil {
@@ -431,13 +431,28 @@ func (c *Client) waitAndRecv(done chan error) error {
}
}
+// sendRecvLegacySyscallErr is a wrapper for sendRecvLegacy that converts all
+// non-syscall errors to EIO.
+func (c *Client) sendRecvLegacySyscallErr(t message, r message) error {
+ received, err := c.sendRecvLegacy(t, r)
+ if !received {
+ log.Warningf("p9.Client.sendRecvChannel: %v", err)
+ return syscall.EIO
+ }
+ return err
+}
+
// sendRecvLegacy performs a roundtrip message exchange.
//
+// sendRecvLegacy returns true if a message was received. This allows us to
+// differentiate between failed receives and successful receives where the
+// response was an error message.
+//
// This is called by internal functions.
-func (c *Client) sendRecvLegacy(t message, r message) error {
+func (c *Client) sendRecvLegacy(t message, r message) (bool, error) {
tag, ok := c.tagPool.Get()
if !ok {
- return ErrOutOfTags
+ return false, ErrOutOfTags
}
defer c.tagPool.Put(tag)
@@ -457,12 +472,12 @@ func (c *Client) sendRecvLegacy(t message, r message) error {
err := send(c.socket, Tag(tag), t)
c.sendMu.Unlock()
if err != nil {
- return err
+ return false, err
}
// Co-ordinate with other receivers.
if err := c.waitAndRecv(resp.done); err != nil {
- return err
+ return false, err
}
// Is it an error message?
@@ -470,14 +485,14 @@ func (c *Client) sendRecvLegacy(t message, r message) error {
// For convenience, we transform these directly
// into errors. Handlers need not handle this case.
if rlerr, ok := resp.r.(*Rlerror); ok {
- return syscall.Errno(rlerr.Error)
+ return true, syscall.Errno(rlerr.Error)
}
// At this point, we know it matches.
//
// Per recv call above, we will only allow a type
// match (and give our r) or an instance of Rlerror.
- return nil
+ return true, nil
}
// sendRecvChannel uses channels to send a message.
@@ -486,7 +501,7 @@ func (c *Client) sendRecvChannel(t message, r message) error {
c.channelsMu.Lock()
if len(c.availableChannels) == 0 {
c.channelsMu.Unlock()
- return c.sendRecvLegacy(t, r)
+ return c.sendRecvLegacySyscallErr(t, r)
}
idx := len(c.availableChannels) - 1
ch := c.availableChannels[idx]
@@ -526,7 +541,11 @@ func (c *Client) sendRecvChannel(t message, r message) error {
}
// Parse the server's response.
- _, retErr := ch.recv(r, rsz)
+ resp, retErr := ch.recv(r, rsz)
+ if resp == nil {
+ log.Warningf("p9.Client.sendRecvChannel: p9.channel.recv: %v", retErr)
+ retErr = syscall.EIO
+ }
// Release the channel.
c.channelsMu.Lock()
diff --git a/pkg/p9/client_test.go b/pkg/p9/client_test.go
index 29a0afadf..c757583e0 100644
--- a/pkg/p9/client_test.go
+++ b/pkg/p9/client_test.go
@@ -96,7 +96,12 @@ func benchmarkSendRecv(b *testing.B, fn func(c *Client) func(message, message) e
}
func BenchmarkSendRecvLegacy(b *testing.B) {
- benchmarkSendRecv(b, func(c *Client) func(message, message) error { return c.sendRecvLegacy })
+ benchmarkSendRecv(b, func(c *Client) func(message, message) error {
+ return func(t message, r message) error {
+ _, err := c.sendRecvLegacy(t, r)
+ return err
+ }
+ })
}
func BenchmarkSendRecvChannel(b *testing.B) {
diff --git a/pkg/p9/transport_flipcall.go b/pkg/p9/transport_flipcall.go
index a0d274f3b..38038abdf 100644
--- a/pkg/p9/transport_flipcall.go
+++ b/pkg/p9/transport_flipcall.go
@@ -236,7 +236,7 @@ func (ch *channel) recv(r message, rsz uint32) (message, error) {
// Convert errors appropriately; see above.
if rlerr, ok := r.(*Rlerror); ok {
- return nil, syscall.Errno(rlerr.Error)
+ return r, syscall.Errno(rlerr.Error)
}
return r, nil
diff --git a/pkg/segment/test/segment_test.go b/pkg/segment/test/segment_test.go
index f19a005f3..97b16c158 100644
--- a/pkg/segment/test/segment_test.go
+++ b/pkg/segment/test/segment_test.go
@@ -63,7 +63,7 @@ func checkSet(s *Set, expectedSegments int) error {
return fmt.Errorf("incorrect order: key %d (segment %d) >= key %d (segment %d)", prev, nrSegments-1, next, nrSegments)
}
if got, want := seg.Value(), seg.Start()+valueOffset; got != want {
- return fmt.Errorf("segment %d has key %d, value %d (expected %d)", nrSegments, seg.Start, got, want)
+ return fmt.Errorf("segment %d has key %d, value %d (expected %d)", nrSegments, seg.Start(), got, want)
}
prev = next
havePrev = true
diff --git a/pkg/sentry/arch/stack.go b/pkg/sentry/arch/stack.go
index 09bceabc9..1108fa0bd 100644
--- a/pkg/sentry/arch/stack.go
+++ b/pkg/sentry/arch/stack.go
@@ -97,7 +97,6 @@ func (s *Stack) Push(vals ...interface{}) (usermem.Addr, error) {
if c < 0 {
return 0, fmt.Errorf("bad binary.Size for %T", v)
}
- // TODO(b/38173783): Use a real context.Context.
n, err := usermem.CopyObjectOut(context.Background(), s.IO, s.Bottom-usermem.Addr(c), norm, usermem.IOOpts{})
if err != nil || c != n {
return 0, err
@@ -121,11 +120,9 @@ func (s *Stack) Pop(vals ...interface{}) (usermem.Addr, error) {
var err error
if isVaddr {
value := s.Arch.Native(uintptr(0))
- // TODO(b/38173783): Use a real context.Context.
n, err = usermem.CopyObjectIn(context.Background(), s.IO, s.Bottom, value, usermem.IOOpts{})
*vaddr = usermem.Addr(s.Arch.Value(value))
} else {
- // TODO(b/38173783): Use a real context.Context.
n, err = usermem.CopyObjectIn(context.Background(), s.IO, s.Bottom, v, usermem.IOOpts{})
}
if err != nil {
diff --git a/pkg/sentry/contexttest/contexttest.go b/pkg/sentry/contexttest/contexttest.go
index 031fc64ec..8e5658c7a 100644
--- a/pkg/sentry/contexttest/contexttest.go
+++ b/pkg/sentry/contexttest/contexttest.go
@@ -97,7 +97,7 @@ type hostClock struct {
}
// Now implements ktime.Clock.Now.
-func (hostClock) Now() ktime.Time {
+func (*hostClock) Now() ktime.Time {
return ktime.FromNanoseconds(time.Now().UnixNano())
}
@@ -127,7 +127,7 @@ func (t *TestContext) Value(key interface{}) interface{} {
case uniqueid.CtxInotifyCookie:
return atomic.AddUint32(&lastInotifyCookie, 1)
case ktime.CtxRealtimeClock:
- return hostClock{}
+ return &hostClock{}
default:
if val, ok := t.otherValues[key]; ok {
return val
diff --git a/pkg/sentry/fs/fdpipe/pipe_test.go b/pkg/sentry/fs/fdpipe/pipe_test.go
index 5aff0cc95..a0082ecca 100644
--- a/pkg/sentry/fs/fdpipe/pipe_test.go
+++ b/pkg/sentry/fs/fdpipe/pipe_test.go
@@ -119,7 +119,7 @@ func TestNewPipe(t *testing.T) {
continue
}
if flags := p.flags; test.flags != flags {
- t.Errorf("%s: got file flags %s, want %s", test.desc, flags, test.flags)
+ t.Errorf("%s: got file flags %v, want %v", test.desc, flags, test.flags)
continue
}
if len(test.readAheadBuffer) != len(p.readAheadBuffer) {
@@ -136,7 +136,7 @@ func TestNewPipe(t *testing.T) {
continue
}
if !fdnotifier.HasFD(int32(f.FD())) {
- t.Errorf("%s: pipe fd %d is not registered for events", test.desc, f.FD)
+ t.Errorf("%s: pipe fd %d is not registered for events", test.desc, f.FD())
}
}
}
diff --git a/pkg/sentry/fs/gofer/file_state.go b/pkg/sentry/fs/gofer/file_state.go
index ff96b28ba..edd6576aa 100644
--- a/pkg/sentry/fs/gofer/file_state.go
+++ b/pkg/sentry/fs/gofer/file_state.go
@@ -34,7 +34,6 @@ func (f *fileOperations) afterLoad() {
flags := f.flags
flags.Truncate = false
- // TODO(b/38173783): Context is not plumbed to save/restore.
f.handles, err = f.inodeOperations.fileState.getHandles(context.Background(), flags, f.inodeOperations.cachingInodeOps)
if err != nil {
return fmt.Errorf("failed to re-open handle: %v", err)
diff --git a/pkg/sentry/fs/gofer/handles.go b/pkg/sentry/fs/gofer/handles.go
index 9f7c3e89f..fc14249be 100644
--- a/pkg/sentry/fs/gofer/handles.go
+++ b/pkg/sentry/fs/gofer/handles.go
@@ -57,7 +57,6 @@ func (h *handles) DecRef() {
}
}
}
- // FIXME(b/38173783): Context is not plumbed here.
if err := h.File.close(context.Background()); err != nil {
log.Warningf("error closing p9 file: %v", err)
}
diff --git a/pkg/sentry/fs/gofer/inode.go b/pkg/sentry/fs/gofer/inode.go
index 811e8ea30..a016c896e 100644
--- a/pkg/sentry/fs/gofer/inode.go
+++ b/pkg/sentry/fs/gofer/inode.go
@@ -273,7 +273,7 @@ func (i *inodeFileState) recreateReadHandles(ctx context.Context, writer *handle
// operations on the old will see the new data. Then, make the new handle take
// ownereship of the old FD and mark the old readHandle to not close the FD
// when done.
- if err := syscall.Dup3(h.Host.FD(), i.readHandles.Host.FD(), 0); err != nil {
+ if err := syscall.Dup3(h.Host.FD(), i.readHandles.Host.FD(), syscall.O_CLOEXEC); err != nil {
return err
}
diff --git a/pkg/sentry/fs/gofer/inode_state.go b/pkg/sentry/fs/gofer/inode_state.go
index 238f7804c..a3402e343 100644
--- a/pkg/sentry/fs/gofer/inode_state.go
+++ b/pkg/sentry/fs/gofer/inode_state.go
@@ -123,7 +123,6 @@ func (i *inodeFileState) afterLoad() {
// beforeSave.
return fmt.Errorf("failed to find path for inode number %d. Device %s contains %s", i.sattr.InodeID, i.s.connID, fs.InodeMappings(i.s.inodeMappings))
}
- // TODO(b/38173783): Context is not plumbed to save/restore.
ctx := &dummyClockContext{context.Background()}
_, i.file, err = i.s.attach.walk(ctx, splitAbsolutePath(name))
diff --git a/pkg/sentry/fs/gofer/session_state.go b/pkg/sentry/fs/gofer/session_state.go
index 111da59f9..2d398b753 100644
--- a/pkg/sentry/fs/gofer/session_state.go
+++ b/pkg/sentry/fs/gofer/session_state.go
@@ -104,7 +104,6 @@ func (s *session) afterLoad() {
// If private unix sockets are enabled, create and fill the session's endpoint
// maps.
if opts.privateunixsocket {
- // TODO(b/38173783): Context is not plumbed to save/restore.
ctx := &dummyClockContext{context.Background()}
if err = s.restoreEndpointMaps(ctx); err != nil {
diff --git a/pkg/sentry/fs/host/socket_test.go b/pkg/sentry/fs/host/socket_test.go
index eb4afe520..affdbcacb 100644
--- a/pkg/sentry/fs/host/socket_test.go
+++ b/pkg/sentry/fs/host/socket_test.go
@@ -199,14 +199,14 @@ func TestListen(t *testing.T) {
}
func TestPasscred(t *testing.T) {
- e := ConnectedEndpoint{}
+ e := &ConnectedEndpoint{}
if got, want := e.Passcred(), false; got != want {
t.Errorf("Got %#v.Passcred() = %t, want = %t", e, got, want)
}
}
func TestGetLocalAddress(t *testing.T) {
- e := ConnectedEndpoint{path: "foo"}
+ e := &ConnectedEndpoint{path: "foo"}
want := tcpip.FullAddress{Addr: tcpip.Address("foo")}
if got, err := e.GetLocalAddress(); err != nil || got != want {
t.Errorf("Got %#v.GetLocalAddress() = %#v, %v, want = %#v, %v", e, got, err, want, nil)
@@ -214,7 +214,7 @@ func TestGetLocalAddress(t *testing.T) {
}
func TestQueuedSize(t *testing.T) {
- e := ConnectedEndpoint{}
+ e := &ConnectedEndpoint{}
tests := []struct {
name string
f func() int64
diff --git a/pkg/sentry/fs/inode.go b/pkg/sentry/fs/inode.go
index 73f89abcc..a34fbc946 100644
--- a/pkg/sentry/fs/inode.go
+++ b/pkg/sentry/fs/inode.go
@@ -102,7 +102,6 @@ func (i *Inode) DecRef() {
// destroy releases the Inode and releases the msrc reference taken.
func (i *Inode) destroy() {
- // FIXME(b/38173783): Context is not plumbed here.
ctx := context.Background()
if err := i.WriteOut(ctx); err != nil {
// FIXME(b/65209558): Mark as warning again once noatime is
diff --git a/pkg/sentry/fs/proc/sys_net.go b/pkg/sentry/fs/proc/sys_net.go
index d4c4b533d..702fdd392 100644
--- a/pkg/sentry/fs/proc/sys_net.go
+++ b/pkg/sentry/fs/proc/sys_net.go
@@ -80,7 +80,7 @@ func newTCPMemInode(ctx context.Context, msrc *fs.MountSource, s inet.Stack, dir
}
// Truncate implements fs.InodeOperations.Truncate.
-func (tcpMemInode) Truncate(context.Context, *fs.Inode, int64) error {
+func (*tcpMemInode) Truncate(context.Context, *fs.Inode, int64) error {
return nil
}
@@ -196,7 +196,7 @@ func newTCPSackInode(ctx context.Context, msrc *fs.MountSource, s inet.Stack) *f
}
// Truncate implements fs.InodeOperations.Truncate.
-func (tcpSack) Truncate(context.Context, *fs.Inode, int64) error {
+func (*tcpSack) Truncate(context.Context, *fs.Inode, int64) error {
return nil
}
diff --git a/pkg/sentry/fsimpl/ext/filesystem.go b/pkg/sentry/fsimpl/ext/filesystem.go
index 48eaccdbc..afea58f65 100644
--- a/pkg/sentry/fsimpl/ext/filesystem.go
+++ b/pkg/sentry/fsimpl/ext/filesystem.go
@@ -476,7 +476,7 @@ func (fs *filesystem) BoundEndpointAt(ctx context.Context, rp *vfs.ResolvingPath
}
// ListxattrAt implements vfs.FilesystemImpl.ListxattrAt.
-func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([]string, error) {
+func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath, size uint64) ([]string, error) {
_, _, err := fs.walk(rp, false)
if err != nil {
return nil, err
@@ -485,7 +485,7 @@ func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([
}
// GetxattrAt implements vfs.FilesystemImpl.GetxattrAt.
-func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, name string) (string, error) {
+func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.GetxattrOptions) (string, error) {
_, _, err := fs.walk(rp, false)
if err != nil {
return "", err
diff --git a/pkg/sentry/fsimpl/gofer/filesystem.go b/pkg/sentry/fsimpl/gofer/filesystem.go
index 137260898..cd744bf5e 100644
--- a/pkg/sentry/fsimpl/gofer/filesystem.go
+++ b/pkg/sentry/fsimpl/gofer/filesystem.go
@@ -1080,7 +1080,7 @@ func (fs *filesystem) BoundEndpointAt(ctx context.Context, rp *vfs.ResolvingPath
}
// ListxattrAt implements vfs.FilesystemImpl.ListxattrAt.
-func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([]string, error) {
+func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath, size uint64) ([]string, error) {
var ds *[]*dentry
fs.renameMu.RLock()
defer fs.renameMuRUnlockAndCheckCaching(&ds)
@@ -1088,11 +1088,11 @@ func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([
if err != nil {
return nil, err
}
- return d.listxattr(ctx)
+ return d.listxattr(ctx, rp.Credentials(), size)
}
// GetxattrAt implements vfs.FilesystemImpl.GetxattrAt.
-func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, name string) (string, error) {
+func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.GetxattrOptions) (string, error) {
var ds *[]*dentry
fs.renameMu.RLock()
defer fs.renameMuRUnlockAndCheckCaching(&ds)
@@ -1100,7 +1100,7 @@ func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, nam
if err != nil {
return "", err
}
- return d.getxattr(ctx, name)
+ return d.getxattr(ctx, rp.Credentials(), &opts)
}
// SetxattrAt implements vfs.FilesystemImpl.SetxattrAt.
@@ -1112,7 +1112,7 @@ func (fs *filesystem) SetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, opt
if err != nil {
return err
}
- return d.setxattr(ctx, &opts)
+ return d.setxattr(ctx, rp.Credentials(), &opts)
}
// RemovexattrAt implements vfs.FilesystemImpl.RemovexattrAt.
@@ -1124,7 +1124,7 @@ func (fs *filesystem) RemovexattrAt(ctx context.Context, rp *vfs.ResolvingPath,
if err != nil {
return err
}
- return d.removexattr(ctx, name)
+ return d.removexattr(ctx, rp.Credentials(), name)
}
// PrependPath implements vfs.FilesystemImpl.PrependPath.
diff --git a/pkg/sentry/fsimpl/gofer/gofer.go b/pkg/sentry/fsimpl/gofer/gofer.go
index 20edaf643..2485cdb53 100644
--- a/pkg/sentry/fsimpl/gofer/gofer.go
+++ b/pkg/sentry/fsimpl/gofer/gofer.go
@@ -34,6 +34,7 @@ package gofer
import (
"fmt"
"strconv"
+ "strings"
"sync"
"sync/atomic"
"syscall"
@@ -1024,21 +1025,50 @@ func (d *dentry) setDeleted() {
atomic.StoreUint32(&d.deleted, 1)
}
-func (d *dentry) listxattr(ctx context.Context) ([]string, error) {
- return nil, syserror.ENOTSUP
+// We only support xattrs prefixed with "user." (see b/148380782). Currently,
+// there is no need to expose any other xattrs through a gofer.
+func (d *dentry) listxattr(ctx context.Context, creds *auth.Credentials, size uint64) ([]string, error) {
+ xattrMap, err := d.file.listXattr(ctx, size)
+ if err != nil {
+ return nil, err
+ }
+ xattrs := make([]string, 0, len(xattrMap))
+ for x := range xattrMap {
+ if strings.HasPrefix(x, linux.XATTR_USER_PREFIX) {
+ xattrs = append(xattrs, x)
+ }
+ }
+ return xattrs, nil
}
-func (d *dentry) getxattr(ctx context.Context, name string) (string, error) {
- // TODO(jamieliu): add vfs.GetxattrOptions.Size
- return d.file.getXattr(ctx, name, linux.XATTR_SIZE_MAX)
+func (d *dentry) getxattr(ctx context.Context, creds *auth.Credentials, opts *vfs.GetxattrOptions) (string, error) {
+ if err := d.checkPermissions(creds, vfs.MayRead); err != nil {
+ return "", err
+ }
+ if !strings.HasPrefix(opts.Name, linux.XATTR_USER_PREFIX) {
+ return "", syserror.EOPNOTSUPP
+ }
+ return d.file.getXattr(ctx, opts.Name, opts.Size)
}
-func (d *dentry) setxattr(ctx context.Context, opts *vfs.SetxattrOptions) error {
+func (d *dentry) setxattr(ctx context.Context, creds *auth.Credentials, opts *vfs.SetxattrOptions) error {
+ if err := d.checkPermissions(creds, vfs.MayWrite); err != nil {
+ return err
+ }
+ if !strings.HasPrefix(opts.Name, linux.XATTR_USER_PREFIX) {
+ return syserror.EOPNOTSUPP
+ }
return d.file.setXattr(ctx, opts.Name, opts.Value, opts.Flags)
}
-func (d *dentry) removexattr(ctx context.Context, name string) error {
- return syserror.ENOTSUP
+func (d *dentry) removexattr(ctx context.Context, creds *auth.Credentials, name string) error {
+ if err := d.checkPermissions(creds, vfs.MayWrite); err != nil {
+ return err
+ }
+ if !strings.HasPrefix(name, linux.XATTR_USER_PREFIX) {
+ return syserror.EOPNOTSUPP
+ }
+ return d.file.removeXattr(ctx, name)
}
// Preconditions: d.isRegularFile() || d.isDirectory().
@@ -1089,7 +1119,7 @@ func (d *dentry) ensureSharedHandle(ctx context.Context, read, write, trunc bool
// description, but this doesn't matter since they refer to the
// same file (unless d.fs.opts.overlayfsStaleRead is true,
// which we handle separately).
- if err := syscall.Dup3(int(h.fd), int(d.handle.fd), 0); err != nil {
+ if err := syscall.Dup3(int(h.fd), int(d.handle.fd), syscall.O_CLOEXEC); err != nil {
d.handleMu.Unlock()
ctx.Warningf("gofer.dentry.ensureSharedHandle: failed to dup fd %d to fd %d: %v", h.fd, d.handle.fd, err)
h.close(ctx)
@@ -1189,21 +1219,21 @@ func (fd *fileDescription) SetStat(ctx context.Context, opts vfs.SetStatOptions)
}
// Listxattr implements vfs.FileDescriptionImpl.Listxattr.
-func (fd *fileDescription) Listxattr(ctx context.Context) ([]string, error) {
- return fd.dentry().listxattr(ctx)
+func (fd *fileDescription) Listxattr(ctx context.Context, size uint64) ([]string, error) {
+ return fd.dentry().listxattr(ctx, auth.CredentialsFromContext(ctx), size)
}
// Getxattr implements vfs.FileDescriptionImpl.Getxattr.
-func (fd *fileDescription) Getxattr(ctx context.Context, name string) (string, error) {
- return fd.dentry().getxattr(ctx, name)
+func (fd *fileDescription) Getxattr(ctx context.Context, opts vfs.GetxattrOptions) (string, error) {
+ return fd.dentry().getxattr(ctx, auth.CredentialsFromContext(ctx), &opts)
}
// Setxattr implements vfs.FileDescriptionImpl.Setxattr.
func (fd *fileDescription) Setxattr(ctx context.Context, opts vfs.SetxattrOptions) error {
- return fd.dentry().setxattr(ctx, &opts)
+ return fd.dentry().setxattr(ctx, auth.CredentialsFromContext(ctx), &opts)
}
// Removexattr implements vfs.FileDescriptionImpl.Removexattr.
func (fd *fileDescription) Removexattr(ctx context.Context, name string) error {
- return fd.dentry().removexattr(ctx, name)
+ return fd.dentry().removexattr(ctx, auth.CredentialsFromContext(ctx), name)
}
diff --git a/pkg/sentry/fsimpl/gofer/p9file.go b/pkg/sentry/fsimpl/gofer/p9file.go
index 755ac2985..87f0b877f 100644
--- a/pkg/sentry/fsimpl/gofer/p9file.go
+++ b/pkg/sentry/fsimpl/gofer/p9file.go
@@ -85,6 +85,13 @@ func (f p9file) setAttr(ctx context.Context, valid p9.SetAttrMask, attr p9.SetAt
return err
}
+func (f p9file) listXattr(ctx context.Context, size uint64) (map[string]struct{}, error) {
+ ctx.UninterruptibleSleepStart(false)
+ xattrs, err := f.file.ListXattr(size)
+ ctx.UninterruptibleSleepFinish(false)
+ return xattrs, err
+}
+
func (f p9file) getXattr(ctx context.Context, name string, size uint64) (string, error) {
ctx.UninterruptibleSleepStart(false)
val, err := f.file.GetXattr(name, size)
@@ -99,6 +106,13 @@ func (f p9file) setXattr(ctx context.Context, name, value string, flags uint32)
return err
}
+func (f p9file) removeXattr(ctx context.Context, name string) error {
+ ctx.UninterruptibleSleepStart(false)
+ err := f.file.RemoveXattr(name)
+ ctx.UninterruptibleSleepFinish(false)
+ return err
+}
+
func (f p9file) allocate(ctx context.Context, mode p9.AllocateMode, offset, length uint64) error {
ctx.UninterruptibleSleepStart(false)
err := f.file.Allocate(mode, offset, length)
diff --git a/pkg/sentry/fsimpl/kernfs/filesystem.go b/pkg/sentry/fsimpl/kernfs/filesystem.go
index 4433071aa..baf81b4db 100644
--- a/pkg/sentry/fsimpl/kernfs/filesystem.go
+++ b/pkg/sentry/fsimpl/kernfs/filesystem.go
@@ -763,7 +763,7 @@ func (fs *Filesystem) BoundEndpointAt(ctx context.Context, rp *vfs.ResolvingPath
}
// ListxattrAt implements vfs.FilesystemImpl.ListxattrAt.
-func (fs *Filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([]string, error) {
+func (fs *Filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath, size uint64) ([]string, error) {
fs.mu.RLock()
_, _, err := fs.walkExistingLocked(ctx, rp)
fs.mu.RUnlock()
@@ -776,7 +776,7 @@ func (fs *Filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([
}
// GetxattrAt implements vfs.FilesystemImpl.GetxattrAt.
-func (fs *Filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, name string) (string, error) {
+func (fs *Filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.GetxattrOptions) (string, error) {
fs.mu.RLock()
_, _, err := fs.walkExistingLocked(ctx, rp)
fs.mu.RUnlock()
diff --git a/pkg/sentry/fsimpl/proc/task_net.go b/pkg/sentry/fsimpl/proc/task_net.go
index 6b2a77328..6595fcee6 100644
--- a/pkg/sentry/fsimpl/proc/task_net.go
+++ b/pkg/sentry/fsimpl/proc/task_net.go
@@ -688,9 +688,9 @@ func (d *netSnmpData) Generate(ctx context.Context, buf *bytes.Buffer) error {
if line.prefix == "Tcp" {
tcp := stat.(*inet.StatSNMPTCP)
// "Tcp" needs special processing because MaxConn is signed. RFC 2012.
- fmt.Sprintf("%s: %s %d %s\n", line.prefix, sprintSlice(tcp[:3]), int64(tcp[3]), sprintSlice(tcp[4:]))
+ fmt.Fprintf(buf, "%s: %s %d %s\n", line.prefix, sprintSlice(tcp[:3]), int64(tcp[3]), sprintSlice(tcp[4:]))
} else {
- fmt.Sprintf("%s: %s\n", line.prefix, sprintSlice(toSlice(stat)))
+ fmt.Fprintf(buf, "%s: %s\n", line.prefix, sprintSlice(toSlice(stat)))
}
}
return nil
diff --git a/pkg/sentry/fsimpl/tmpfs/BUILD b/pkg/sentry/fsimpl/tmpfs/BUILD
index f2ac23c88..4e6cd3491 100644
--- a/pkg/sentry/fsimpl/tmpfs/BUILD
+++ b/pkg/sentry/fsimpl/tmpfs/BUILD
@@ -51,6 +51,7 @@ go_library(
"//pkg/sentry/usage",
"//pkg/sentry/vfs",
"//pkg/sentry/vfs/lock",
+ "//pkg/sentry/vfs/memxattr",
"//pkg/sync",
"//pkg/syserror",
"//pkg/usermem",
diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go
index 5339d7072..f4d50d64f 100644
--- a/pkg/sentry/fsimpl/tmpfs/filesystem.go
+++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go
@@ -696,51 +696,47 @@ func (fs *filesystem) BoundEndpointAt(ctx context.Context, rp *vfs.ResolvingPath
}
// ListxattrAt implements vfs.FilesystemImpl.ListxattrAt.
-func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath) ([]string, error) {
+func (fs *filesystem) ListxattrAt(ctx context.Context, rp *vfs.ResolvingPath, size uint64) ([]string, error) {
fs.mu.RLock()
defer fs.mu.RUnlock()
- _, err := resolveLocked(rp)
+ d, err := resolveLocked(rp)
if err != nil {
return nil, err
}
- // TODO(b/127675828): support extended attributes
- return nil, syserror.ENOTSUP
+ return d.inode.listxattr(size)
}
// GetxattrAt implements vfs.FilesystemImpl.GetxattrAt.
-func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, name string) (string, error) {
+func (fs *filesystem) GetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.GetxattrOptions) (string, error) {
fs.mu.RLock()
defer fs.mu.RUnlock()
- _, err := resolveLocked(rp)
+ d, err := resolveLocked(rp)
if err != nil {
return "", err
}
- // TODO(b/127675828): support extended attributes
- return "", syserror.ENOTSUP
+ return d.inode.getxattr(rp.Credentials(), &opts)
}
// SetxattrAt implements vfs.FilesystemImpl.SetxattrAt.
func (fs *filesystem) SetxattrAt(ctx context.Context, rp *vfs.ResolvingPath, opts vfs.SetxattrOptions) error {
fs.mu.RLock()
defer fs.mu.RUnlock()
- _, err := resolveLocked(rp)
+ d, err := resolveLocked(rp)
if err != nil {
return err
}
- // TODO(b/127675828): support extended attributes
- return syserror.ENOTSUP
+ return d.inode.setxattr(rp.Credentials(), &opts)
}
// RemovexattrAt implements vfs.FilesystemImpl.RemovexattrAt.
func (fs *filesystem) RemovexattrAt(ctx context.Context, rp *vfs.ResolvingPath, name string) error {
fs.mu.RLock()
defer fs.mu.RUnlock()
- _, err := resolveLocked(rp)
+ d, err := resolveLocked(rp)
if err != nil {
return err
}
- // TODO(b/127675828): support extended attributes
- return syserror.ENOTSUP
+ return d.inode.removexattr(rp.Credentials(), name)
}
// PrependPath implements vfs.FilesystemImpl.PrependPath.
diff --git a/pkg/sentry/fsimpl/tmpfs/stat_test.go b/pkg/sentry/fsimpl/tmpfs/stat_test.go
index 3e02e7190..d4f59ee5b 100644
--- a/pkg/sentry/fsimpl/tmpfs/stat_test.go
+++ b/pkg/sentry/fsimpl/tmpfs/stat_test.go
@@ -140,7 +140,7 @@ func TestSetStatAtime(t *testing.T) {
Mask: 0,
Atime: linux.NsecToStatxTimestamp(100),
}}); err != nil {
- t.Errorf("SetStat atime without mask failed: %v")
+ t.Errorf("SetStat atime without mask failed: %v", err)
}
// Atime should be unchanged.
if gotStat, err := fd.Stat(ctx, allStatOptions); err != nil {
@@ -155,7 +155,7 @@ func TestSetStatAtime(t *testing.T) {
Atime: linux.NsecToStatxTimestamp(100),
}
if err := fd.SetStat(ctx, vfs.SetStatOptions{Stat: setStat}); err != nil {
- t.Errorf("SetStat atime with mask failed: %v")
+ t.Errorf("SetStat atime with mask failed: %v", err)
}
if gotStat, err := fd.Stat(ctx, allStatOptions); err != nil {
t.Errorf("Stat got error: %v", err)
@@ -205,7 +205,7 @@ func TestSetStat(t *testing.T) {
Mask: 0,
Atime: linux.NsecToStatxTimestamp(100),
}}); err != nil {
- t.Errorf("SetStat atime without mask failed: %v")
+ t.Errorf("SetStat atime without mask failed: %v", err)
}
// Atime should be unchanged.
if gotStat, err := fd.Stat(ctx, allStatOptions); err != nil {
@@ -220,7 +220,7 @@ func TestSetStat(t *testing.T) {
Atime: linux.NsecToStatxTimestamp(100),
}
if err := fd.SetStat(ctx, vfs.SetStatOptions{Stat: setStat}); err != nil {
- t.Errorf("SetStat atime with mask failed: %v")
+ t.Errorf("SetStat atime with mask failed: %v", err)
}
if gotStat, err := fd.Stat(ctx, allStatOptions); err != nil {
t.Errorf("Stat got error: %v", err)
diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go
index 654e788e3..9fa8637d5 100644
--- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go
+++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go
@@ -27,6 +27,7 @@ package tmpfs
import (
"fmt"
"math"
+ "strings"
"sync/atomic"
"gvisor.dev/gvisor/pkg/abi/linux"
@@ -37,6 +38,7 @@ import (
"gvisor.dev/gvisor/pkg/sentry/pgalloc"
"gvisor.dev/gvisor/pkg/sentry/vfs"
"gvisor.dev/gvisor/pkg/sentry/vfs/lock"
+ "gvisor.dev/gvisor/pkg/sentry/vfs/memxattr"
"gvisor.dev/gvisor/pkg/sync"
"gvisor.dev/gvisor/pkg/syserror"
)
@@ -186,6 +188,11 @@ type inode struct {
// filesystem.RmdirAt() drops the reference.
refs int64
+ // xattrs implements extended attributes.
+ //
+ // TODO(b/148380782): Support xattrs other than user.*
+ xattrs memxattr.SimpleExtendedAttributes
+
// Inode metadata. Writing multiple fields atomically requires holding
// mu, othewise atomic operations can be used.
mu sync.Mutex
@@ -535,6 +542,56 @@ func (i *inode) touchCMtimeLocked() {
atomic.StoreInt64(&i.ctime, now)
}
+func (i *inode) listxattr(size uint64) ([]string, error) {
+ return i.xattrs.Listxattr(size)
+}
+
+func (i *inode) getxattr(creds *auth.Credentials, opts *vfs.GetxattrOptions) (string, error) {
+ if err := i.checkPermissions(creds, vfs.MayRead); err != nil {
+ return "", err
+ }
+ if !strings.HasPrefix(opts.Name, linux.XATTR_USER_PREFIX) {
+ return "", syserror.EOPNOTSUPP
+ }
+ if !i.userXattrSupported() {
+ return "", syserror.ENODATA
+ }
+ return i.xattrs.Getxattr(opts)
+}
+
+func (i *inode) setxattr(creds *auth.Credentials, opts *vfs.SetxattrOptions) error {
+ if err := i.checkPermissions(creds, vfs.MayWrite); err != nil {
+ return err
+ }
+ if !strings.HasPrefix(opts.Name, linux.XATTR_USER_PREFIX) {
+ return syserror.EOPNOTSUPP
+ }
+ if !i.userXattrSupported() {
+ return syserror.EPERM
+ }
+ return i.xattrs.Setxattr(opts)
+}
+
+func (i *inode) removexattr(creds *auth.Credentials, name string) error {
+ if err := i.checkPermissions(creds, vfs.MayWrite); err != nil {
+ return err
+ }
+ if !strings.HasPrefix(name, linux.XATTR_USER_PREFIX) {
+ return syserror.EOPNOTSUPP
+ }
+ if !i.userXattrSupported() {
+ return syserror.EPERM
+ }
+ return i.xattrs.Removexattr(name)
+}
+
+// Extended attributes in the user.* namespace are only supported for regular
+// files and directories.
+func (i *inode) userXattrSupported() bool {
+ filetype := linux.S_IFMT & atomic.LoadUint32(&i.mode)
+ return filetype == linux.S_IFREG || filetype == linux.S_IFDIR
+}
+
// fileDescription is embedded by tmpfs implementations of
// vfs.FileDescriptionImpl.
type fileDescription struct {
@@ -562,3 +619,23 @@ func (fd *fileDescription) SetStat(ctx context.Context, opts vfs.SetStatOptions)
creds := auth.CredentialsFromContext(ctx)
return fd.inode().setStat(ctx, creds, &opts.Stat)
}
+
+// Listxattr implements vfs.FileDescriptionImpl.Listxattr.
+func (fd *fileDescription) Listxattr(ctx context.Context, size uint64) ([]string, error) {
+ return fd.inode().listxattr(size)
+}
+
+// Getxattr implements vfs.FileDescriptionImpl.Getxattr.
+func (fd *fileDescription) Getxattr(ctx context.Context, opts vfs.GetxattrOptions) (string, error) {
+ return fd.inode().getxattr(auth.CredentialsFromContext(ctx), &opts)
+}
+
+// Setxattr implements vfs.FileDescriptionImpl.Setxattr.
+func (fd *fileDescription) Setxattr(ctx context.Context, opts vfs.SetxattrOptions) error {
+ return fd.inode().setxattr(auth.CredentialsFromContext(ctx), &opts)
+}
+
+// Removexattr implements vfs.FileDescriptionImpl.Removexattr.
+func (fd *fileDescription) Removexattr(ctx context.Context, name string) error {
+ return fd.inode().removexattr(auth.CredentialsFromContext(ctx), name)
+}
diff --git a/pkg/sentry/kernel/fd_table.go b/pkg/sentry/kernel/fd_table.go
index d09d97825..ed40b5303 100644
--- a/pkg/sentry/kernel/fd_table.go
+++ b/pkg/sentry/kernel/fd_table.go
@@ -307,6 +307,61 @@ func (f *FDTable) NewFDs(ctx context.Context, fd int32, files []*fs.File, flags
return fds, nil
}
+// NewFDsVFS2 allocates new FDs guaranteed to be the lowest number available
+// greater than or equal to the fd parameter. All files will share the set
+// flags. Success is guaranteed to be all or none.
+func (f *FDTable) NewFDsVFS2(ctx context.Context, fd int32, files []*vfs.FileDescription, flags FDFlags) (fds []int32, err error) {
+ if fd < 0 {
+ // Don't accept negative FDs.
+ return nil, syscall.EINVAL
+ }
+
+ // Default limit.
+ end := int32(math.MaxInt32)
+
+ // Ensure we don't get past the provided limit.
+ if limitSet := limits.FromContext(ctx); limitSet != nil {
+ lim := limitSet.Get(limits.NumberOfFiles)
+ if lim.Cur != limits.Infinity {
+ end = int32(lim.Cur)
+ }
+ if fd >= end {
+ return nil, syscall.EMFILE
+ }
+ }
+
+ f.mu.Lock()
+ defer f.mu.Unlock()
+
+ // From f.next to find available fd.
+ if fd < f.next {
+ fd = f.next
+ }
+
+ // Install all entries.
+ for i := fd; i < end && len(fds) < len(files); i++ {
+ if d, _, _ := f.getVFS2(i); d == nil {
+ f.setVFS2(i, files[len(fds)], flags) // Set the descriptor.
+ fds = append(fds, i) // Record the file descriptor.
+ }
+ }
+
+ // Failure? Unwind existing FDs.
+ if len(fds) < len(files) {
+ for _, i := range fds {
+ f.setVFS2(i, nil, FDFlags{}) // Zap entry.
+ }
+ return nil, syscall.EMFILE
+ }
+
+ if fd == f.next {
+ // Update next search start position.
+ f.next = fds[len(fds)-1] + 1
+ }
+
+ return fds, nil
+}
+
// NewFDVFS2 allocates a file descriptor greater than or equal to minfd for
// the given file description. If it succeeds, it takes a reference on file.
func (f *FDTable) NewFDVFS2(ctx context.Context, minfd int32, file *vfs.FileDescription, flags FDFlags) (int32, error) {
diff --git a/pkg/sentry/kernel/shm/shm.go b/pkg/sentry/kernel/shm/shm.go
index 208569057..f66cfcc7f 100644
--- a/pkg/sentry/kernel/shm/shm.go
+++ b/pkg/sentry/kernel/shm/shm.go
@@ -461,7 +461,7 @@ func (s *Shm) AddMapping(ctx context.Context, _ memmap.MappingSpace, _ usermem.A
func (s *Shm) RemoveMapping(ctx context.Context, _ memmap.MappingSpace, _ usermem.AddrRange, _ uint64, _ bool) {
s.mu.Lock()
defer s.mu.Unlock()
- // TODO(b/38173783): RemoveMapping may be called during task exit, when ctx
+ // RemoveMapping may be called during task exit, when ctx
// is context.Background. Gracefully handle missing clocks. Failing to
// update the detach time in these cases is ok, since no one can observe the
// omission.
diff --git a/pkg/sentry/kernel/syscalls.go b/pkg/sentry/kernel/syscalls.go
index 93c4fe969..2e3565747 100644
--- a/pkg/sentry/kernel/syscalls.go
+++ b/pkg/sentry/kernel/syscalls.go
@@ -209,65 +209,61 @@ type Stracer interface {
// SyscallEnter is called on syscall entry.
//
// The returned private data is passed to SyscallExit.
- //
- // TODO(gvisor.dev/issue/155): remove kernel imports from the strace
- // package so that the type can be used directly.
SyscallEnter(t *Task, sysno uintptr, args arch.SyscallArguments, flags uint32) interface{}
// SyscallExit is called on syscall exit.
SyscallExit(context interface{}, t *Task, sysno, rval uintptr, err error)
}
-// SyscallTable is a lookup table of system calls. Critically, a SyscallTable
-// is *immutable*. In order to make supporting suspend and resume sane, they
-// must be uniquely registered and may not change during operation.
+// SyscallTable is a lookup table of system calls.
//
-// +stateify savable
+// Note that a SyscallTable is not savable directly. Instead, they are saved as
+// an OS/Arch pair and lookup happens again on restore.
type SyscallTable struct {
// OS is the operating system that this syscall table implements.
- OS abi.OS `state:"wait"`
+ OS abi.OS
// Arch is the architecture that this syscall table targets.
- Arch arch.Arch `state:"wait"`
+ Arch arch.Arch
// The OS version that this syscall table implements.
- Version Version `state:"manual"`
+ Version Version
// AuditNumber is a numeric constant that represents the syscall table. If
// non-zero, auditNumber must be one of the AUDIT_ARCH_* values defined by
// linux/audit.h.
- AuditNumber uint32 `state:"manual"`
+ AuditNumber uint32
// Table is the collection of functions.
- Table map[uintptr]Syscall `state:"manual"`
+ Table map[uintptr]Syscall
// lookup is a fixed-size array that holds the syscalls (indexed by
// their numbers). It is used for fast look ups.
- lookup []SyscallFn `state:"manual"`
+ lookup []SyscallFn
// Emulate is a collection of instruction addresses to emulate. The
// keys are addresses, and the values are system call numbers.
- Emulate map[usermem.Addr]uintptr `state:"manual"`
+ Emulate map[usermem.Addr]uintptr
// The function to call in case of a missing system call.
- Missing MissingFn `state:"manual"`
+ Missing MissingFn
// Stracer traces this syscall table.
- Stracer Stracer `state:"manual"`
+ Stracer Stracer
// External is used to handle an external callback.
- External func(*Kernel) `state:"manual"`
+ External func(*Kernel)
// ExternalFilterBefore is called before External is called before the syscall is executed.
// External is not called if it returns false.
- ExternalFilterBefore func(*Task, uintptr, arch.SyscallArguments) bool `state:"manual"`
+ ExternalFilterBefore func(*Task, uintptr, arch.SyscallArguments) bool
// ExternalFilterAfter is called before External is called after the syscall is executed.
// External is not called if it returns false.
- ExternalFilterAfter func(*Task, uintptr, arch.SyscallArguments) bool `state:"manual"`
+ ExternalFilterAfter func(*Task, uintptr, arch.SyscallArguments) bool
// FeatureEnable stores the strace and one-shot enable bits.
- FeatureEnable SyscallFlagsTable `state:"manual"`
+ FeatureEnable SyscallFlagsTable
}
// allSyscallTables contains all known tables.
diff --git a/pkg/sentry/kernel/syscalls_state.go b/pkg/sentry/kernel/syscalls_state.go
index 00358326b..90f890495 100644
--- a/pkg/sentry/kernel/syscalls_state.go
+++ b/pkg/sentry/kernel/syscalls_state.go
@@ -14,16 +14,34 @@
package kernel
-import "fmt"
+import (
+ "fmt"
-// afterLoad is invoked by stateify.
-func (s *SyscallTable) afterLoad() {
- otherTable, ok := LookupSyscallTable(s.OS, s.Arch)
- if !ok {
- // Couldn't find a reference?
- panic(fmt.Sprintf("syscall table not found for OS %v Arch %v", s.OS, s.Arch))
+ "gvisor.dev/gvisor/pkg/abi"
+ "gvisor.dev/gvisor/pkg/sentry/arch"
+)
+
+// syscallTableInfo is used to reload the SyscallTable.
+//
+// +stateify savable
+type syscallTableInfo struct {
+ OS abi.OS
+ Arch arch.Arch
+}
+
+// saveSt saves the SyscallTable.
+func (tc *TaskContext) saveSt() syscallTableInfo {
+ return syscallTableInfo{
+ OS: tc.st.OS,
+ Arch: tc.st.Arch,
}
+}
- // Copy the table.
- *s = *otherTable
+// loadSt loads the SyscallTable.
+func (tc *TaskContext) loadSt(sti syscallTableInfo) {
+ st, ok := LookupSyscallTable(sti.OS, sti.Arch)
+ if !ok {
+ panic(fmt.Sprintf("syscall table not found for OS %v, Arch %v", sti.OS, sti.Arch))
+ }
+ tc.st = st // Save the table reference.
}
diff --git a/pkg/sentry/kernel/task.go b/pkg/sentry/kernel/task.go
index d6546735e..e5d133d6c 100644
--- a/pkg/sentry/kernel/task.go
+++ b/pkg/sentry/kernel/task.go
@@ -777,6 +777,15 @@ func (t *Task) NewFDs(fd int32, files []*fs.File, flags FDFlags) ([]int32, error
return t.fdTable.NewFDs(t, fd, files, flags)
}
+// NewFDsVFS2 is a convenience wrapper for t.FDTable().NewFDsVFS2.
+//
+// This automatically passes the task as the context.
+//
+// Precondition: same as FDTable.
+func (t *Task) NewFDsVFS2(fd int32, files []*vfs.FileDescription, flags FDFlags) ([]int32, error) {
+ return t.fdTable.NewFDsVFS2(t, fd, files, flags)
+}
+
// NewFDFrom is a convenience wrapper for t.FDTable().NewFDs with a single file.
//
// This automatically passes the task as the context.
diff --git a/pkg/sentry/kernel/task_context.go b/pkg/sentry/kernel/task_context.go
index 0158b1788..9fa528384 100644
--- a/pkg/sentry/kernel/task_context.go
+++ b/pkg/sentry/kernel/task_context.go
@@ -49,7 +49,7 @@ type TaskContext struct {
fu *futex.Manager
// st is the task's syscall table.
- st *SyscallTable
+ st *SyscallTable `state:".(syscallTableInfo)"`
}
// release releases all resources held by the TaskContext. release is called by
@@ -58,7 +58,6 @@ func (tc *TaskContext) release() {
// Nil out pointers so that if the task is saved after release, it doesn't
// follow the pointers to possibly now-invalid objects.
if tc.MemoryManager != nil {
- // TODO(b/38173783)
tc.MemoryManager.DecUsers(context.Background())
tc.MemoryManager = nil
}
diff --git a/pkg/sentry/kernel/task_identity.go b/pkg/sentry/kernel/task_identity.go
index ce3e6ef28..0325967e4 100644
--- a/pkg/sentry/kernel/task_identity.go
+++ b/pkg/sentry/kernel/task_identity.go
@@ -455,7 +455,7 @@ func (t *Task) SetKeepCaps(k bool) {
t.creds.Store(creds)
}
-// updateCredsForExec updates t.creds to reflect an execve().
+// updateCredsForExecLocked updates t.creds to reflect an execve().
//
// NOTE(b/30815691): We currently do not implement privileged executables
// (set-user/group-ID bits and file capabilities). This allows us to make a lot
diff --git a/pkg/sentry/kernel/task_signals.go b/pkg/sentry/kernel/task_signals.go
index 8802db142..6aa798346 100644
--- a/pkg/sentry/kernel/task_signals.go
+++ b/pkg/sentry/kernel/task_signals.go
@@ -513,8 +513,6 @@ func (t *Task) canReceiveSignalLocked(sig linux.Signal) bool {
if t.stop != nil {
return false
}
- // - TODO(b/38173783): No special case for when t is also the sending task,
- // because the identity of the sender is unknown.
// - Do not choose tasks that have already been interrupted, as they may be
// busy handling another signal.
if len(t.interruptChan) != 0 {
diff --git a/pkg/sentry/kernel/time/time.go b/pkg/sentry/kernel/time/time.go
index 706de83ef..e959700f2 100644
--- a/pkg/sentry/kernel/time/time.go
+++ b/pkg/sentry/kernel/time/time.go
@@ -245,7 +245,7 @@ type Clock interface {
type WallRateClock struct{}
// WallTimeUntil implements Clock.WallTimeUntil.
-func (WallRateClock) WallTimeUntil(t, now Time) time.Duration {
+func (*WallRateClock) WallTimeUntil(t, now Time) time.Duration {
return t.Sub(now)
}
@@ -254,16 +254,16 @@ func (WallRateClock) WallTimeUntil(t, now Time) time.Duration {
type NoClockEvents struct{}
// Readiness implements waiter.Waitable.Readiness.
-func (NoClockEvents) Readiness(mask waiter.EventMask) waiter.EventMask {
+func (*NoClockEvents) Readiness(mask waiter.EventMask) waiter.EventMask {
return 0
}
// EventRegister implements waiter.Waitable.EventRegister.
-func (NoClockEvents) EventRegister(e *waiter.Entry, mask waiter.EventMask) {
+func (*NoClockEvents) EventRegister(e *waiter.Entry, mask waiter.EventMask) {
}
// EventUnregister implements waiter.Waitable.EventUnregister.
-func (NoClockEvents) EventUnregister(e *waiter.Entry) {
+func (*NoClockEvents) EventUnregister(e *waiter.Entry) {
}
// ClockEventsQueue implements waiter.Waitable by wrapping waiter.Queue and
@@ -273,7 +273,7 @@ type ClockEventsQueue struct {
}
// Readiness implements waiter.Waitable.Readiness.
-func (ClockEventsQueue) Readiness(mask waiter.EventMask) waiter.EventMask {
+func (*ClockEventsQueue) Readiness(mask waiter.EventMask) waiter.EventMask {
return 0
}
diff --git a/pkg/sentry/platform/kvm/kvm_arm64.go b/pkg/sentry/platform/kvm/kvm_arm64.go
index 79045651e..716198712 100644
--- a/pkg/sentry/platform/kvm/kvm_arm64.go
+++ b/pkg/sentry/platform/kvm/kvm_arm64.go
@@ -18,6 +18,8 @@ package kvm
import (
"syscall"
+
+ "gvisor.dev/gvisor/pkg/sentry/platform/ring0"
)
type kvmOneReg struct {
@@ -46,6 +48,6 @@ type userRegs struct {
func updateGlobalOnce(fd int) error {
physicalInit()
err := updateSystemValues(int(fd))
- updateVectorTable()
+ ring0.Init()
return err
}
diff --git a/pkg/sentry/platform/kvm/machine_arm64_unsafe.go b/pkg/sentry/platform/kvm/machine_arm64_unsafe.go
index b531f2f85..3b35858ae 100644
--- a/pkg/sentry/platform/kvm/machine_arm64_unsafe.go
+++ b/pkg/sentry/platform/kvm/machine_arm64_unsafe.go
@@ -48,69 +48,6 @@ func (m *machine) initArchState() error {
return nil
}
-func getPageWithReflect(p uintptr) []byte {
- return (*(*[0xFFFFFF]byte)(unsafe.Pointer(p & ^uintptr(syscall.Getpagesize()-1))))[:syscall.Getpagesize()]
-}
-
-// Work around: move ring0.Vectors() into a specific address with 11-bits alignment.
-//
-// According to the design documentation of Arm64,
-// the start address of exception vector table should be 11-bits aligned.
-// Please see the code in linux kernel as reference: arch/arm64/kernel/entry.S
-// But, we can't align a function's start address to a specific address by using golang.
-// We have raised this question in golang community:
-// https://groups.google.com/forum/m/#!topic/golang-dev/RPj90l5x86I
-// This function will be removed when golang supports this feature.
-//
-// There are 2 jobs were implemented in this function:
-// 1, move the start address of exception vector table into the specific address.
-// 2, modify the offset of each instruction.
-func updateVectorTable() {
- fromLocation := reflect.ValueOf(ring0.Vectors).Pointer()
- offset := fromLocation & (1<<11 - 1)
- if offset != 0 {
- offset = 1<<11 - offset
- }
-
- toLocation := fromLocation + offset
- page := getPageWithReflect(toLocation)
- if err := syscall.Mprotect(page, syscall.PROT_READ|syscall.PROT_WRITE|syscall.PROT_EXEC); err != nil {
- panic(err)
- }
-
- page = getPageWithReflect(toLocation + 4096)
- if err := syscall.Mprotect(page, syscall.PROT_READ|syscall.PROT_WRITE|syscall.PROT_EXEC); err != nil {
- panic(err)
- }
-
- // Move exception-vector-table into the specific address.
- var entry *uint32
- var entryFrom *uint32
- for i := 1; i <= 0x800; i++ {
- entry = (*uint32)(unsafe.Pointer(toLocation + 0x800 - uintptr(i)))
- entryFrom = (*uint32)(unsafe.Pointer(fromLocation + 0x800 - uintptr(i)))
- *entry = *entryFrom
- }
-
- // The offset from the address of each unconditionally branch is changed.
- // We should modify the offset of each instruction.
- nums := []uint32{0x0, 0x80, 0x100, 0x180, 0x200, 0x280, 0x300, 0x380, 0x400, 0x480, 0x500, 0x580, 0x600, 0x680, 0x700, 0x780}
- for _, num := range nums {
- entry = (*uint32)(unsafe.Pointer(toLocation + uintptr(num)))
- *entry = *entry - (uint32)(offset/4)
- }
-
- page = getPageWithReflect(toLocation)
- if err := syscall.Mprotect(page, syscall.PROT_READ|syscall.PROT_EXEC); err != nil {
- panic(err)
- }
-
- page = getPageWithReflect(toLocation + 4096)
- if err := syscall.Mprotect(page, syscall.PROT_READ|syscall.PROT_EXEC); err != nil {
- panic(err)
- }
-}
-
// initArchState initializes architecture-specific state.
func (c *vCPU) initArchState() error {
var (
diff --git a/pkg/sentry/platform/ring0/BUILD b/pkg/sentry/platform/ring0/BUILD
index 934b6fbcd..b69520030 100644
--- a/pkg/sentry/platform/ring0/BUILD
+++ b/pkg/sentry/platform/ring0/BUILD
@@ -72,11 +72,13 @@ go_library(
"lib_amd64.s",
"lib_arm64.go",
"lib_arm64.s",
+ "lib_arm64_unsafe.go",
"ring0.go",
],
visibility = ["//pkg/sentry:internal"],
deps = [
"//pkg/cpuid",
+ "//pkg/safecopy",
"//pkg/sentry/platform/ring0/pagetables",
"//pkg/usermem",
],
diff --git a/pkg/sentry/platform/ring0/lib_arm64.go b/pkg/sentry/platform/ring0/lib_arm64.go
index af075aae4..242b9305c 100644
--- a/pkg/sentry/platform/ring0/lib_arm64.go
+++ b/pkg/sentry/platform/ring0/lib_arm64.go
@@ -37,3 +37,10 @@ func SaveVRegs(*byte)
// LoadVRegs loads V0-V31 registers.
func LoadVRegs(*byte)
+
+// Init sets function pointers based on architectural features.
+//
+// This must be called prior to using ring0.
+func Init() {
+ rewriteVectors()
+}
diff --git a/pkg/sentry/platform/ring0/lib_arm64_unsafe.go b/pkg/sentry/platform/ring0/lib_arm64_unsafe.go
new file mode 100644
index 000000000..c05166fea
--- /dev/null
+++ b/pkg/sentry/platform/ring0/lib_arm64_unsafe.go
@@ -0,0 +1,108 @@
+// Copyright 2019 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build arm64
+
+package ring0
+
+import (
+ "reflect"
+ "syscall"
+ "unsafe"
+
+ "gvisor.dev/gvisor/pkg/safecopy"
+ "gvisor.dev/gvisor/pkg/usermem"
+)
+
+const (
+ nopInstruction = 0xd503201f
+ instSize = unsafe.Sizeof(uint32(0))
+ vectorsRawLen = 0x800
+)
+
+func unsafeSlice(addr uintptr, length int) (slice []uint32) {
+ hdr := (*reflect.SliceHeader)(unsafe.Pointer(&slice))
+ hdr.Data = addr
+ hdr.Len = length / int(instSize)
+ hdr.Cap = length / int(instSize)
+ return slice
+}
+
+// Work around: move ring0.Vectors() into a specific address with 11-bits alignment.
+//
+// According to the design documentation of Arm64,
+// the start address of exception vector table should be 11-bits aligned.
+// Please see the code in linux kernel as reference: arch/arm64/kernel/entry.S
+// But, we can't align a function's start address to a specific address by using golang.
+// We have raised this question in golang community:
+// https://groups.google.com/forum/m/#!topic/golang-dev/RPj90l5x86I
+// This function will be removed when golang supports this feature.
+//
+// There are 2 jobs were implemented in this function:
+// 1, move the start address of exception vector table into the specific address.
+// 2, modify the offset of each instruction.
+func rewriteVectors() {
+ vectorsBegin := reflect.ValueOf(Vectors).Pointer()
+
+ // The exception-vector-table is required to be 11-bits aligned.
+ // And the size is 0x800.
+ // Please see the documentation as reference:
+ // https://developer.arm.com/docs/100933/0100/aarch64-exception-vector-table
+ //
+ // But, golang does not allow to set a function's address to a specific value.
+ // So, for gvisor, I defined the size of exception-vector-table as 4K,
+ // filled the 2nd 2K part with NOP-s.
+ // So that, I can safely move the 1st 2K part into the address with 11-bits alignment.
+ //
+ // So, the prerequisite for this function to work correctly is:
+ // vectorsSafeLen >= 0x1000
+ // vectorsRawLen = 0x800
+ vectorsSafeLen := int(safecopy.FindEndAddress(vectorsBegin) - vectorsBegin)
+ if vectorsSafeLen < 2*vectorsRawLen {
+ panic("Can't update vectors")
+ }
+
+ vectorsSafeTable := unsafeSlice(vectorsBegin, vectorsSafeLen) // Now a []uint32
+ vectorsRawLen32 := vectorsRawLen / int(instSize)
+
+ offset := vectorsBegin & (1<<11 - 1)
+ if offset != 0 {
+ offset = 1<<11 - offset
+ }
+
+ pageBegin := (vectorsBegin + offset) & ^uintptr(usermem.PageSize-1)
+
+ _, _, errno := syscall.Syscall(syscall.SYS_MPROTECT, uintptr(pageBegin), uintptr(usermem.PageSize), uintptr(syscall.PROT_READ|syscall.PROT_WRITE|syscall.PROT_EXEC))
+ if errno != 0 {
+ panic(errno.Error())
+ }
+
+ offset = offset / instSize // By index, not bytes.
+ // Move exception-vector-table into the specific address, should uses memmove here.
+ for i := 1; i <= vectorsRawLen32; i++ {
+ vectorsSafeTable[int(offset)+vectorsRawLen32-i] = vectorsSafeTable[vectorsRawLen32-i]
+ }
+
+ // Adjust branch since instruction was moved forward.
+ for i := 0; i < vectorsRawLen32; i++ {
+ if vectorsSafeTable[int(offset)+i] != nopInstruction {
+ vectorsSafeTable[int(offset)+i] -= uint32(offset)
+ }
+ }
+
+ _, _, errno = syscall.Syscall(syscall.SYS_MPROTECT, uintptr(pageBegin), uintptr(usermem.PageSize), uintptr(syscall.PROT_READ|syscall.PROT_EXEC))
+ if errno != 0 {
+ panic(errno.Error())
+ }
+}
diff --git a/pkg/sentry/strace/strace.go b/pkg/sentry/strace/strace.go
index 77655558e..b94c4fbf5 100644
--- a/pkg/sentry/strace/strace.go
+++ b/pkg/sentry/strace/strace.go
@@ -778,9 +778,6 @@ func (s SyscallMap) Name(sysno uintptr) string {
//
// N.B. This is not in an init function because we can't be sure all syscall
// tables are registered with the kernel when init runs.
-//
-// TODO(gvisor.dev/issue/155): remove kernel package dependencies from this
-// package and have the kernel package self-initialize all syscall tables.
func Initialize() {
for _, table := range kernel.SyscallTables() {
// Is this known?
diff --git a/pkg/sentry/syscalls/linux/sys_prctl.go b/pkg/sentry/syscalls/linux/sys_prctl.go
index 9c6728530..f92bf8096 100644
--- a/pkg/sentry/syscalls/linux/sys_prctl.go
+++ b/pkg/sentry/syscalls/linux/sys_prctl.go
@@ -161,8 +161,8 @@ func Prctl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall
if args[1].Int() != 1 || args[2].Int() != 0 || args[3].Int() != 0 || args[4].Int() != 0 {
return 0, nil, syserror.EINVAL
}
- // no_new_privs is assumed to always be set. See
- // kernel.Task.updateCredsForExec.
+ // PR_SET_NO_NEW_PRIVS is assumed to always be set.
+ // See kernel.Task.updateCredsForExecLocked.
return 0, nil, nil
case linux.PR_GET_NO_NEW_PRIVS:
diff --git a/pkg/sentry/syscalls/linux/sys_socket.go b/pkg/sentry/syscalls/linux/sys_socket.go
index 2919228d0..61b2576ac 100644
--- a/pkg/sentry/syscalls/linux/sys_socket.go
+++ b/pkg/sentry/syscalls/linux/sys_socket.go
@@ -31,6 +31,8 @@ import (
"gvisor.dev/gvisor/pkg/usermem"
)
+// LINT.IfChange
+
// minListenBacklog is the minimum reasonable backlog for listening sockets.
const minListenBacklog = 8
@@ -244,7 +246,10 @@ func SocketPair(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sy
// Copy the file descriptors out.
if _, err := t.CopyOut(socks, fds); err != nil {
- // Note that we don't close files here; see pipe(2) also.
+ for _, fd := range fds {
+ _, file := t.FDTable().Remove(fd)
+ file.DecRef()
+ }
return 0, nil, err
}
@@ -1128,3 +1133,5 @@ func SendTo(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal
n, err := sendTo(t, fd, bufPtr, bufLen, flags, namePtr, nameLen)
return n, nil, err
}
+
+// LINT.ThenChange(./vfs2/socket.go)
diff --git a/pkg/sentry/syscalls/linux/vfs2/BUILD b/pkg/sentry/syscalls/linux/vfs2/BUILD
index 0004e60d9..b32abfe59 100644
--- a/pkg/sentry/syscalls/linux/vfs2/BUILD
+++ b/pkg/sentry/syscalls/linux/vfs2/BUILD
@@ -21,6 +21,7 @@ go_library(
"poll.go",
"read_write.go",
"setstat.go",
+ "socket.go",
"stat.go",
"stat_amd64.go",
"stat_arm64.go",
@@ -32,6 +33,7 @@ go_library(
visibility = ["//:sandbox"],
deps = [
"//pkg/abi/linux",
+ "//pkg/binary",
"//pkg/bits",
"//pkg/fspath",
"//pkg/gohacks",
@@ -43,10 +45,14 @@ go_library(
"//pkg/sentry/limits",
"//pkg/sentry/loader",
"//pkg/sentry/memmap",
+ "//pkg/sentry/socket",
+ "//pkg/sentry/socket/control",
+ "//pkg/sentry/socket/unix/transport",
"//pkg/sentry/syscalls",
"//pkg/sentry/syscalls/linux",
"//pkg/sentry/vfs",
"//pkg/sync",
+ "//pkg/syserr",
"//pkg/syserror",
"//pkg/usermem",
"//pkg/waiter",
diff --git a/pkg/sentry/syscalls/linux/vfs2/getdents.go b/pkg/sentry/syscalls/linux/vfs2/getdents.go
index a61cc5059..62e98817d 100644
--- a/pkg/sentry/syscalls/linux/vfs2/getdents.go
+++ b/pkg/sentry/syscalls/linux/vfs2/getdents.go
@@ -97,6 +97,7 @@ func (cb *getdentsCallback) Handle(dirent vfs.Dirent) error {
// char d_name[]; /* Filename (null-terminated) */
// };
size := 8 + 8 + 2 + 1 + 1 + len(dirent.Name)
+ size = (size + 7) &^ 7 // round up to multiple of 8
if size > cb.remaining {
return syserror.EINVAL
}
@@ -106,7 +107,12 @@ func (cb *getdentsCallback) Handle(dirent vfs.Dirent) error {
usermem.ByteOrder.PutUint16(buf[16:18], uint16(size))
buf[18] = dirent.Type
copy(buf[19:], dirent.Name)
- buf[size-1] = 0 // NUL terminator
+ // Zero out all remaining bytes in buf, including the NUL terminator
+ // after dirent.Name.
+ bufTail := buf[19+len(dirent.Name):]
+ for i := range bufTail {
+ bufTail[i] = 0
+ }
} else {
// struct linux_dirent {
// unsigned long d_ino; /* Inode number */
@@ -125,6 +131,7 @@ func (cb *getdentsCallback) Handle(dirent vfs.Dirent) error {
panic(fmt.Sprintf("unsupported sizeof(unsigned long): %d", cb.t.Arch().Width()))
}
size := 8 + 8 + 2 + 1 + 1 + 1 + len(dirent.Name)
+ size = (size + 7) &^ 7 // round up to multiple of sizeof(long)
if size > cb.remaining {
return syserror.EINVAL
}
@@ -133,9 +140,14 @@ func (cb *getdentsCallback) Handle(dirent vfs.Dirent) error {
usermem.ByteOrder.PutUint64(buf[8:16], uint64(dirent.NextOff))
usermem.ByteOrder.PutUint16(buf[16:18], uint16(size))
copy(buf[18:], dirent.Name)
- buf[size-3] = 0 // NUL terminator
- buf[size-2] = 0 // zero padding byte
- buf[size-1] = dirent.Type
+ // Zero out all remaining bytes in buf, including the NUL terminator
+ // after dirent.Name and the zero padding byte between the name and
+ // dirent type.
+ bufTail := buf[18+len(dirent.Name):]
+ for i := range bufTail {
+ bufTail[i] = 0
+ }
+ bufTail[2] = dirent.Type
}
n, err := cb.t.CopyOutBytes(cb.addr, buf)
if err != nil {
diff --git a/pkg/sentry/syscalls/linux/vfs2/linux64_override_amd64.go b/pkg/sentry/syscalls/linux/vfs2/linux64_override_amd64.go
index 63febc2f7..645e0bcb8 100644
--- a/pkg/sentry/syscalls/linux/vfs2/linux64_override_amd64.go
+++ b/pkg/sentry/syscalls/linux/vfs2/linux64_override_amd64.go
@@ -44,21 +44,22 @@ func Override(table map[uintptr]kernel.Syscall) {
table[32] = syscalls.Supported("dup", Dup)
table[33] = syscalls.Supported("dup2", Dup2)
delete(table, 40) // sendfile
- delete(table, 41) // socket
- delete(table, 42) // connect
- delete(table, 43) // accept
- delete(table, 44) // sendto
- delete(table, 45) // recvfrom
- delete(table, 46) // sendmsg
- delete(table, 47) // recvmsg
- delete(table, 48) // shutdown
- delete(table, 49) // bind
- delete(table, 50) // listen
- delete(table, 51) // getsockname
- delete(table, 52) // getpeername
- delete(table, 53) // socketpair
- delete(table, 54) // setsockopt
- delete(table, 55) // getsockopt
+ // TODO(gvisor.dev/issue/1485): Port all socket variants to VFS2.
+ table[41] = syscalls.PartiallySupported("socket", Socket, "In process of porting socket syscalls to VFS2.", nil)
+ table[42] = syscalls.PartiallySupported("connect", Connect, "In process of porting socket syscalls to VFS2.", nil)
+ table[43] = syscalls.PartiallySupported("accept", Accept, "In process of porting socket syscalls to VFS2.", nil)
+ table[44] = syscalls.PartiallySupported("sendto", SendTo, "In process of porting socket syscalls to VFS2.", nil)
+ table[45] = syscalls.PartiallySupported("recvfrom", RecvFrom, "In process of porting socket syscalls to VFS2.", nil)
+ table[46] = syscalls.PartiallySupported("sendmsg", SendMsg, "In process of porting socket syscalls to VFS2.", nil)
+ table[47] = syscalls.PartiallySupported("recvmsg", RecvMsg, "In process of porting socket syscalls to VFS2.", nil)
+ table[48] = syscalls.PartiallySupported("shutdown", Shutdown, "In process of porting socket syscalls to VFS2.", nil)
+ table[49] = syscalls.PartiallySupported("bind", Bind, "In process of porting socket syscalls to VFS2.", nil)
+ table[50] = syscalls.PartiallySupported("listen", Listen, "In process of porting socket syscalls to VFS2.", nil)
+ table[51] = syscalls.PartiallySupported("getsockname", GetSockName, "In process of porting socket syscalls to VFS2.", nil)
+ table[52] = syscalls.PartiallySupported("getpeername", GetPeerName, "In process of porting socket syscalls to VFS2.", nil)
+ table[53] = syscalls.PartiallySupported("socketpair", SocketPair, "In process of porting socket syscalls to VFS2.", nil)
+ table[54] = syscalls.PartiallySupported("getsockopt", GetSockOpt, "In process of porting socket syscalls to VFS2.", nil)
+ table[55] = syscalls.PartiallySupported("setsockopt", SetSockOpt, "In process of porting socket syscalls to VFS2.", nil)
table[59] = syscalls.Supported("execve", Execve)
table[72] = syscalls.Supported("fcntl", Fcntl)
delete(table, 73) // flock
@@ -144,7 +145,8 @@ func Override(table map[uintptr]kernel.Syscall) {
delete(table, 285) // fallocate
table[286] = syscalls.Supported("timerfd_settime", TimerfdSettime)
table[287] = syscalls.Supported("timerfd_gettime", TimerfdGettime)
- delete(table, 288) // accept4
+ // TODO(gvisor.dev/issue/1485): Port all socket variants to VFS2.
+ table[288] = syscalls.PartiallySupported("accept4", Accept4, "In process of porting socket syscalls to VFS2.", nil)
delete(table, 289) // signalfd4
delete(table, 290) // eventfd2
table[291] = syscalls.Supported("epoll_create1", EpollCreate1)
@@ -153,9 +155,11 @@ func Override(table map[uintptr]kernel.Syscall) {
delete(table, 294) // inotify_init1
table[295] = syscalls.Supported("preadv", Preadv)
table[296] = syscalls.Supported("pwritev", Pwritev)
- delete(table, 299) // recvmmsg
+ // TODO(gvisor.dev/issue/1485): Port all socket variants to VFS2.
+ table[299] = syscalls.PartiallySupported("recvmmsg", RecvMMsg, "In process of porting socket syscalls to VFS2.", nil)
table[306] = syscalls.Supported("syncfs", Syncfs)
- delete(table, 307) // sendmmsg
+ // TODO(gvisor.dev/issue/1485): Port all socket variants to VFS2.
+ table[307] = syscalls.PartiallySupported("sendmmsg", SendMMsg, "In process of porting socket syscalls to VFS2.", nil)
table[316] = syscalls.Supported("renameat2", Renameat2)
delete(table, 319) // memfd_create
table[322] = syscalls.Supported("execveat", Execveat)
diff --git a/pkg/sentry/syscalls/linux/vfs2/socket.go b/pkg/sentry/syscalls/linux/vfs2/socket.go
new file mode 100644
index 000000000..79a4a7ada
--- /dev/null
+++ b/pkg/sentry/syscalls/linux/vfs2/socket.go
@@ -0,0 +1,1138 @@
+// Copyright 2018 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package vfs2
+
+import (
+ "time"
+
+ "gvisor.dev/gvisor/pkg/abi/linux"
+ "gvisor.dev/gvisor/pkg/binary"
+ "gvisor.dev/gvisor/pkg/sentry/arch"
+ "gvisor.dev/gvisor/pkg/sentry/kernel"
+ ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time"
+ "gvisor.dev/gvisor/pkg/sentry/socket"
+ "gvisor.dev/gvisor/pkg/sentry/socket/control"
+ "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport"
+ slinux "gvisor.dev/gvisor/pkg/sentry/syscalls/linux"
+ "gvisor.dev/gvisor/pkg/sentry/vfs"
+ "gvisor.dev/gvisor/pkg/syserr"
+ "gvisor.dev/gvisor/pkg/syserror"
+ "gvisor.dev/gvisor/pkg/usermem"
+)
+
+// minListenBacklog is the minimum reasonable backlog for listening sockets.
+const minListenBacklog = 8
+
+// maxListenBacklog is the maximum allowed backlog for listening sockets.
+const maxListenBacklog = 1024
+
+// maxAddrLen is the maximum socket address length we're willing to accept.
+const maxAddrLen = 200
+
+// maxOptLen is the maximum sockopt parameter length we're willing to accept.
+const maxOptLen = 1024 * 8
+
+// maxControlLen is the maximum length of the msghdr.msg_control buffer we're
+// willing to accept. Note that this limit is smaller than Linux, which allows
+// buffers upto INT_MAX.
+const maxControlLen = 10 * 1024 * 1024
+
+// nameLenOffset is the offset from the start of the MessageHeader64 struct to
+// the NameLen field.
+const nameLenOffset = 8
+
+// controlLenOffset is the offset form the start of the MessageHeader64 struct
+// to the ControlLen field.
+const controlLenOffset = 40
+
+// flagsOffset is the offset form the start of the MessageHeader64 struct
+// to the Flags field.
+const flagsOffset = 48
+
+const sizeOfInt32 = 4
+
+// messageHeader64Len is the length of a MessageHeader64 struct.
+var messageHeader64Len = uint64(binary.Size(MessageHeader64{}))
+
+// multipleMessageHeader64Len is the length of a multipeMessageHeader64 struct.
+var multipleMessageHeader64Len = uint64(binary.Size(multipleMessageHeader64{}))
+
+// baseRecvFlags are the flags that are accepted across recvmsg(2),
+// recvmmsg(2), and recvfrom(2).
+const baseRecvFlags = linux.MSG_OOB | linux.MSG_DONTROUTE | linux.MSG_DONTWAIT | linux.MSG_NOSIGNAL | linux.MSG_WAITALL | linux.MSG_TRUNC | linux.MSG_CTRUNC
+
+// MessageHeader64 is the 64-bit representation of the msghdr struct used in
+// the recvmsg and sendmsg syscalls.
+type MessageHeader64 struct {
+ // Name is the optional pointer to a network address buffer.
+ Name uint64
+
+ // NameLen is the length of the buffer pointed to by Name.
+ NameLen uint32
+ _ uint32
+
+ // Iov is a pointer to an array of io vectors that describe the memory
+ // locations involved in the io operation.
+ Iov uint64
+
+ // IovLen is the length of the array pointed to by Iov.
+ IovLen uint64
+
+ // Control is the optional pointer to ancillary control data.
+ Control uint64
+
+ // ControlLen is the length of the data pointed to by Control.
+ ControlLen uint64
+
+ // Flags on the sent/received message.
+ Flags int32
+ _ int32
+}
+
+// multipleMessageHeader64 is the 64-bit representation of the mmsghdr struct used in
+// the recvmmsg and sendmmsg syscalls.
+type multipleMessageHeader64 struct {
+ msgHdr MessageHeader64
+ msgLen uint32
+ _ int32
+}
+
+// CopyInMessageHeader64 copies a message header from user to kernel memory.
+func CopyInMessageHeader64(t *kernel.Task, addr usermem.Addr, msg *MessageHeader64) error {
+ b := t.CopyScratchBuffer(52)
+ if _, err := t.CopyInBytes(addr, b); err != nil {
+ return err
+ }
+
+ msg.Name = usermem.ByteOrder.Uint64(b[0:])
+ msg.NameLen = usermem.ByteOrder.Uint32(b[8:])
+ msg.Iov = usermem.ByteOrder.Uint64(b[16:])
+ msg.IovLen = usermem.ByteOrder.Uint64(b[24:])
+ msg.Control = usermem.ByteOrder.Uint64(b[32:])
+ msg.ControlLen = usermem.ByteOrder.Uint64(b[40:])
+ msg.Flags = int32(usermem.ByteOrder.Uint32(b[48:]))
+
+ return nil
+}
+
+// CaptureAddress allocates memory for and copies a socket address structure
+// from the untrusted address space range.
+func CaptureAddress(t *kernel.Task, addr usermem.Addr, addrlen uint32) ([]byte, error) {
+ if addrlen > maxAddrLen {
+ return nil, syserror.EINVAL
+ }
+
+ addrBuf := make([]byte, addrlen)
+ if _, err := t.CopyInBytes(addr, addrBuf); err != nil {
+ return nil, err
+ }
+
+ return addrBuf, nil
+}
+
+// writeAddress writes a sockaddr structure and its length to an output buffer
+// in the unstrusted address space range. If the address is bigger than the
+// buffer, it is truncated.
+func writeAddress(t *kernel.Task, addr interface{}, addrLen uint32, addrPtr usermem.Addr, addrLenPtr usermem.Addr) error {
+ // Get the buffer length.
+ var bufLen uint32
+ if _, err := t.CopyIn(addrLenPtr, &bufLen); err != nil {
+ return err
+ }
+
+ if int32(bufLen) < 0 {
+ return syserror.EINVAL
+ }
+
+ // Write the length unconditionally.
+ if _, err := t.CopyOut(addrLenPtr, addrLen); err != nil {
+ return err
+ }
+
+ if addr == nil {
+ return nil
+ }
+
+ if bufLen > addrLen {
+ bufLen = addrLen
+ }
+
+ // Copy as much of the address as will fit in the buffer.
+ encodedAddr := binary.Marshal(nil, usermem.ByteOrder, addr)
+ if bufLen > uint32(len(encodedAddr)) {
+ bufLen = uint32(len(encodedAddr))
+ }
+ _, err := t.CopyOutBytes(addrPtr, encodedAddr[:int(bufLen)])
+ return err
+}
+
+// Socket implements the linux syscall socket(2).
+func Socket(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ domain := int(args[0].Int())
+ stype := args[1].Int()
+ protocol := int(args[2].Int())
+
+ // Check and initialize the flags.
+ if stype & ^(0xf|linux.SOCK_NONBLOCK|linux.SOCK_CLOEXEC) != 0 {
+ return 0, nil, syserror.EINVAL
+ }
+
+ // Create the new socket.
+ s, e := socket.NewVFS2(t, domain, linux.SockType(stype&0xf), protocol)
+ if e != nil {
+ return 0, nil, e.ToError()
+ }
+ defer s.DecRef()
+
+ if err := s.SetStatusFlags(t, t.Credentials(), uint32(stype&linux.SOCK_NONBLOCK)); err != nil {
+ return 0, nil, err
+ }
+
+ fd, err := t.NewFDFromVFS2(0, s, kernel.FDFlags{
+ CloseOnExec: stype&linux.SOCK_CLOEXEC != 0,
+ })
+ if err != nil {
+ return 0, nil, err
+ }
+
+ return uintptr(fd), nil, nil
+}
+
+// SocketPair implements the linux syscall socketpair(2).
+func SocketPair(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ domain := int(args[0].Int())
+ stype := args[1].Int()
+ protocol := int(args[2].Int())
+ addr := args[3].Pointer()
+
+ // Check and initialize the flags.
+ if stype & ^(0xf|linux.SOCK_NONBLOCK|linux.SOCK_CLOEXEC) != 0 {
+ return 0, nil, syserror.EINVAL
+ }
+
+ // Create the socket pair.
+ s1, s2, e := socket.PairVFS2(t, domain, linux.SockType(stype&0xf), protocol)
+ if e != nil {
+ return 0, nil, e.ToError()
+ }
+ // Adding to the FD table will cause an extra reference to be acquired.
+ defer s1.DecRef()
+ defer s2.DecRef()
+
+ nonblocking := uint32(stype & linux.SOCK_NONBLOCK)
+ if err := s1.SetStatusFlags(t, t.Credentials(), nonblocking); err != nil {
+ return 0, nil, err
+ }
+ if err := s2.SetStatusFlags(t, t.Credentials(), nonblocking); err != nil {
+ return 0, nil, err
+ }
+
+ // Create the FDs for the sockets.
+ flags := kernel.FDFlags{
+ CloseOnExec: stype&linux.SOCK_CLOEXEC != 0,
+ }
+ fds, err := t.NewFDsVFS2(0, []*vfs.FileDescription{s1, s2}, flags)
+ if err != nil {
+ return 0, nil, err
+ }
+
+ if _, err := t.CopyOut(addr, fds); err != nil {
+ for _, fd := range fds {
+ _, file := t.FDTable().Remove(fd)
+ file.DecRef()
+ }
+ return 0, nil, err
+ }
+
+ return 0, nil, nil
+}
+
+// Connect implements the linux syscall connect(2).
+func Connect(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ fd := args[0].Int()
+ addr := args[1].Pointer()
+ addrlen := args[2].Uint()
+
+ // Get socket from the file descriptor.
+ file := t.GetFileVFS2(fd)
+ if file == nil {
+ return 0, nil, syserror.EBADF
+ }
+ defer file.DecRef()
+
+ // Extract the socket.
+ s, ok := file.Impl().(socket.SocketVFS2)
+ if !ok {
+ return 0, nil, syserror.ENOTSOCK
+ }
+
+ // Capture address and call syscall implementation.
+ a, err := CaptureAddress(t, addr, addrlen)
+ if err != nil {
+ return 0, nil, err
+ }
+
+ blocking := (file.StatusFlags() & linux.SOCK_NONBLOCK) == 0
+ return 0, nil, syserror.ConvertIntr(s.Connect(t, a, blocking).ToError(), kernel.ERESTARTSYS)
+}
+
+// accept is the implementation of the accept syscall. It is called by accept
+// and accept4 syscall handlers.
+func accept(t *kernel.Task, fd int32, addr usermem.Addr, addrLen usermem.Addr, flags int) (uintptr, error) {
+ // Check that no unsupported flags are passed in.
+ if flags & ^(linux.SOCK_NONBLOCK|linux.SOCK_CLOEXEC) != 0 {
+ return 0, syserror.EINVAL
+ }
+
+ // Get socket from the file descriptor.
+ file := t.GetFileVFS2(fd)
+ if file == nil {
+ return 0, syserror.EBADF
+ }
+ defer file.DecRef()
+
+ // Extract the socket.
+ s, ok := file.Impl().(socket.SocketVFS2)
+ if !ok {
+ return 0, syserror.ENOTSOCK
+ }
+
+ // Call the syscall implementation for this socket, then copy the
+ // output address if one is specified.
+ blocking := (file.StatusFlags() & linux.SOCK_NONBLOCK) == 0
+
+ peerRequested := addrLen != 0
+ nfd, peer, peerLen, e := s.Accept(t, peerRequested, flags, blocking)
+ if e != nil {
+ return 0, syserror.ConvertIntr(e.ToError(), kernel.ERESTARTSYS)
+ }
+ if peerRequested {
+ // NOTE(magi): Linux does not give you an error if it can't
+ // write the data back out so neither do we.
+ if err := writeAddress(t, peer, peerLen, addr, addrLen); err == syserror.EINVAL {
+ return 0, err
+ }
+ }
+ return uintptr(nfd), nil
+}
+
+// Accept4 implements the linux syscall accept4(2).
+func Accept4(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ fd := args[0].Int()
+ addr := args[1].Pointer()
+ addrlen := args[2].Pointer()
+ flags := int(args[3].Int())
+
+ n, err := accept(t, fd, addr, addrlen, flags)
+ return n, nil, err
+}
+
+// Accept implements the linux syscall accept(2).
+func Accept(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ fd := args[0].Int()
+ addr := args[1].Pointer()
+ addrlen := args[2].Pointer()
+
+ n, err := accept(t, fd, addr, addrlen, 0)
+ return n, nil, err
+}
+
+// Bind implements the linux syscall bind(2).
+func Bind(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ fd := args[0].Int()
+ addr := args[1].Pointer()
+ addrlen := args[2].Uint()
+
+ // Get socket from the file descriptor.
+ file := t.GetFileVFS2(fd)
+ if file == nil {
+ return 0, nil, syserror.EBADF
+ }
+ defer file.DecRef()
+
+ // Extract the socket.
+ s, ok := file.Impl().(socket.SocketVFS2)
+ if !ok {
+ return 0, nil, syserror.ENOTSOCK
+ }
+
+ // Capture address and call syscall implementation.
+ a, err := CaptureAddress(t, addr, addrlen)
+ if err != nil {
+ return 0, nil, err
+ }
+
+ return 0, nil, s.Bind(t, a).ToError()
+}
+
+// Listen implements the linux syscall listen(2).
+func Listen(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ fd := args[0].Int()
+ backlog := args[1].Int()
+
+ // Get socket from the file descriptor.
+ file := t.GetFileVFS2(fd)
+ if file == nil {
+ return 0, nil, syserror.EBADF
+ }
+ defer file.DecRef()
+
+ // Extract the socket.
+ s, ok := file.Impl().(socket.SocketVFS2)
+ if !ok {
+ return 0, nil, syserror.ENOTSOCK
+ }
+
+ // Per Linux, the backlog is silently capped to reasonable values.
+ if backlog <= 0 {
+ backlog = minListenBacklog
+ }
+ if backlog > maxListenBacklog {
+ backlog = maxListenBacklog
+ }
+
+ return 0, nil, s.Listen(t, int(backlog)).ToError()
+}
+
+// Shutdown implements the linux syscall shutdown(2).
+func Shutdown(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ fd := args[0].Int()
+ how := args[1].Int()
+
+ // Get socket from the file descriptor.
+ file := t.GetFileVFS2(fd)
+ if file == nil {
+ return 0, nil, syserror.EBADF
+ }
+ defer file.DecRef()
+
+ // Extract the socket.
+ s, ok := file.Impl().(socket.SocketVFS2)
+ if !ok {
+ return 0, nil, syserror.ENOTSOCK
+ }
+
+ // Validate how, then call syscall implementation.
+ switch how {
+ case linux.SHUT_RD, linux.SHUT_WR, linux.SHUT_RDWR:
+ default:
+ return 0, nil, syserror.EINVAL
+ }
+
+ return 0, nil, s.Shutdown(t, int(how)).ToError()
+}
+
+// GetSockOpt implements the linux syscall getsockopt(2).
+func GetSockOpt(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ fd := args[0].Int()
+ level := args[1].Int()
+ name := args[2].Int()
+ optValAddr := args[3].Pointer()
+ optLenAddr := args[4].Pointer()
+
+ // Get socket from the file descriptor.
+ file := t.GetFileVFS2(fd)
+ if file == nil {
+ return 0, nil, syserror.EBADF
+ }
+ defer file.DecRef()
+
+ // Extract the socket.
+ s, ok := file.Impl().(socket.SocketVFS2)
+ if !ok {
+ return 0, nil, syserror.ENOTSOCK
+ }
+
+ // Read the length. Reject negative values.
+ optLen := int32(0)
+ if _, err := t.CopyIn(optLenAddr, &optLen); err != nil {
+ return 0, nil, err
+ }
+ if optLen < 0 {
+ return 0, nil, syserror.EINVAL
+ }
+
+ // Call syscall implementation then copy both value and value len out.
+ v, e := getSockOpt(t, s, int(level), int(name), optValAddr, int(optLen))
+ if e != nil {
+ return 0, nil, e.ToError()
+ }
+
+ vLen := int32(binary.Size(v))
+ if _, err := t.CopyOut(optLenAddr, vLen); err != nil {
+ return 0, nil, err
+ }
+
+ if v != nil {
+ if _, err := t.CopyOut(optValAddr, v); err != nil {
+ return 0, nil, err
+ }
+ }
+
+ return 0, nil, nil
+}
+
+// getSockOpt tries to handle common socket options, or dispatches to a specific
+// socket implementation.
+func getSockOpt(t *kernel.Task, s socket.SocketVFS2, level, name int, optValAddr usermem.Addr, len int) (interface{}, *syserr.Error) {
+ if level == linux.SOL_SOCKET {
+ switch name {
+ case linux.SO_TYPE, linux.SO_DOMAIN, linux.SO_PROTOCOL:
+ if len < sizeOfInt32 {
+ return nil, syserr.ErrInvalidArgument
+ }
+ }
+
+ switch name {
+ case linux.SO_TYPE:
+ _, skType, _ := s.Type()
+ return int32(skType), nil
+ case linux.SO_DOMAIN:
+ family, _, _ := s.Type()
+ return int32(family), nil
+ case linux.SO_PROTOCOL:
+ _, _, protocol := s.Type()
+ return int32(protocol), nil
+ }
+ }
+
+ return s.GetSockOpt(t, level, name, optValAddr, len)
+}
+
+// SetSockOpt implements the linux syscall setsockopt(2).
+//
+// Note that unlike Linux, enabling SO_PASSCRED does not autobind the socket.
+func SetSockOpt(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ fd := args[0].Int()
+ level := args[1].Int()
+ name := args[2].Int()
+ optValAddr := args[3].Pointer()
+ optLen := args[4].Int()
+
+ // Get socket from the file descriptor.
+ file := t.GetFileVFS2(fd)
+ if file == nil {
+ return 0, nil, syserror.EBADF
+ }
+ defer file.DecRef()
+
+ // Extract the socket.
+ s, ok := file.Impl().(socket.SocketVFS2)
+ if !ok {
+ return 0, nil, syserror.ENOTSOCK
+ }
+
+ if optLen < 0 {
+ return 0, nil, syserror.EINVAL
+ }
+ if optLen > maxOptLen {
+ return 0, nil, syserror.EINVAL
+ }
+ buf := t.CopyScratchBuffer(int(optLen))
+ if _, err := t.CopyIn(optValAddr, &buf); err != nil {
+ return 0, nil, err
+ }
+
+ // Call syscall implementation.
+ if err := s.SetSockOpt(t, int(level), int(name), buf); err != nil {
+ return 0, nil, err.ToError()
+ }
+
+ return 0, nil, nil
+}
+
+// GetSockName implements the linux syscall getsockname(2).
+func GetSockName(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ fd := args[0].Int()
+ addr := args[1].Pointer()
+ addrlen := args[2].Pointer()
+
+ // Get socket from the file descriptor.
+ file := t.GetFileVFS2(fd)
+ if file == nil {
+ return 0, nil, syserror.EBADF
+ }
+ defer file.DecRef()
+
+ // Extract the socket.
+ s, ok := file.Impl().(socket.SocketVFS2)
+ if !ok {
+ return 0, nil, syserror.ENOTSOCK
+ }
+
+ // Get the socket name and copy it to the caller.
+ v, vl, err := s.GetSockName(t)
+ if err != nil {
+ return 0, nil, err.ToError()
+ }
+
+ return 0, nil, writeAddress(t, v, vl, addr, addrlen)
+}
+
+// GetPeerName implements the linux syscall getpeername(2).
+func GetPeerName(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ fd := args[0].Int()
+ addr := args[1].Pointer()
+ addrlen := args[2].Pointer()
+
+ // Get socket from the file descriptor.
+ file := t.GetFileVFS2(fd)
+ if file == nil {
+ return 0, nil, syserror.EBADF
+ }
+ defer file.DecRef()
+
+ // Extract the socket.
+ s, ok := file.Impl().(socket.SocketVFS2)
+ if !ok {
+ return 0, nil, syserror.ENOTSOCK
+ }
+
+ // Get the socket peer name and copy it to the caller.
+ v, vl, err := s.GetPeerName(t)
+ if err != nil {
+ return 0, nil, err.ToError()
+ }
+
+ return 0, nil, writeAddress(t, v, vl, addr, addrlen)
+}
+
+// RecvMsg implements the linux syscall recvmsg(2).
+func RecvMsg(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ fd := args[0].Int()
+ msgPtr := args[1].Pointer()
+ flags := args[2].Int()
+
+ if t.Arch().Width() != 8 {
+ // We only handle 64-bit for now.
+ return 0, nil, syserror.EINVAL
+ }
+
+ // Get socket from the file descriptor.
+ file := t.GetFileVFS2(fd)
+ if file == nil {
+ return 0, nil, syserror.EBADF
+ }
+ defer file.DecRef()
+
+ // Extract the socket.
+ s, ok := file.Impl().(socket.SocketVFS2)
+ if !ok {
+ return 0, nil, syserror.ENOTSOCK
+ }
+
+ // Reject flags that we don't handle yet.
+ if flags & ^(baseRecvFlags|linux.MSG_PEEK|linux.MSG_CMSG_CLOEXEC|linux.MSG_ERRQUEUE) != 0 {
+ return 0, nil, syserror.EINVAL
+ }
+
+ if (file.StatusFlags() & linux.SOCK_NONBLOCK) != 0 {
+ flags |= linux.MSG_DONTWAIT
+ }
+
+ var haveDeadline bool
+ var deadline ktime.Time
+ if dl := s.RecvTimeout(); dl > 0 {
+ deadline = t.Kernel().MonotonicClock().Now().Add(time.Duration(dl) * time.Nanosecond)
+ haveDeadline = true
+ } else if dl < 0 {
+ flags |= linux.MSG_DONTWAIT
+ }
+
+ n, err := recvSingleMsg(t, s, msgPtr, flags, haveDeadline, deadline)
+ return n, nil, err
+}
+
+// RecvMMsg implements the linux syscall recvmmsg(2).
+func RecvMMsg(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ fd := args[0].Int()
+ msgPtr := args[1].Pointer()
+ vlen := args[2].Uint()
+ flags := args[3].Int()
+ toPtr := args[4].Pointer()
+
+ if t.Arch().Width() != 8 {
+ // We only handle 64-bit for now.
+ return 0, nil, syserror.EINVAL
+ }
+
+ // Reject flags that we don't handle yet.
+ if flags & ^(baseRecvFlags|linux.MSG_CMSG_CLOEXEC|linux.MSG_ERRQUEUE) != 0 {
+ return 0, nil, syserror.EINVAL
+ }
+
+ // Get socket from the file descriptor.
+ file := t.GetFileVFS2(fd)
+ if file == nil {
+ return 0, nil, syserror.EBADF
+ }
+ defer file.DecRef()
+
+ // Extract the socket.
+ s, ok := file.Impl().(socket.SocketVFS2)
+ if !ok {
+ return 0, nil, syserror.ENOTSOCK
+ }
+
+ if (file.StatusFlags() & linux.SOCK_NONBLOCK) != 0 {
+ flags |= linux.MSG_DONTWAIT
+ }
+
+ var haveDeadline bool
+ var deadline ktime.Time
+ if toPtr != 0 {
+ var ts linux.Timespec
+ if _, err := ts.CopyIn(t, toPtr); err != nil {
+ return 0, nil, err
+ }
+ if !ts.Valid() {
+ return 0, nil, syserror.EINVAL
+ }
+ deadline = t.Kernel().MonotonicClock().Now().Add(ts.ToDuration())
+ haveDeadline = true
+ }
+
+ if !haveDeadline {
+ if dl := s.RecvTimeout(); dl > 0 {
+ deadline = t.Kernel().MonotonicClock().Now().Add(time.Duration(dl) * time.Nanosecond)
+ haveDeadline = true
+ } else if dl < 0 {
+ flags |= linux.MSG_DONTWAIT
+ }
+ }
+
+ var count uint32
+ var err error
+ for i := uint64(0); i < uint64(vlen); i++ {
+ mp, ok := msgPtr.AddLength(i * multipleMessageHeader64Len)
+ if !ok {
+ return 0, nil, syserror.EFAULT
+ }
+ var n uintptr
+ if n, err = recvSingleMsg(t, s, mp, flags, haveDeadline, deadline); err != nil {
+ break
+ }
+
+ // Copy the received length to the caller.
+ lp, ok := mp.AddLength(messageHeader64Len)
+ if !ok {
+ return 0, nil, syserror.EFAULT
+ }
+ if _, err = t.CopyOut(lp, uint32(n)); err != nil {
+ break
+ }
+ count++
+ }
+
+ if count == 0 {
+ return 0, nil, err
+ }
+ return uintptr(count), nil, nil
+}
+
+func recvSingleMsg(t *kernel.Task, s socket.SocketVFS2, msgPtr usermem.Addr, flags int32, haveDeadline bool, deadline ktime.Time) (uintptr, error) {
+ // Capture the message header and io vectors.
+ var msg MessageHeader64
+ if err := CopyInMessageHeader64(t, msgPtr, &msg); err != nil {
+ return 0, err
+ }
+
+ if msg.IovLen > linux.UIO_MAXIOV {
+ return 0, syserror.EMSGSIZE
+ }
+ dst, err := t.IovecsIOSequence(usermem.Addr(msg.Iov), int(msg.IovLen), usermem.IOOpts{
+ AddressSpaceActive: true,
+ })
+ if err != nil {
+ return 0, err
+ }
+
+ // FIXME(b/63594852): Pretend we have an empty error queue.
+ if flags&linux.MSG_ERRQUEUE != 0 {
+ return 0, syserror.EAGAIN
+ }
+
+ // Fast path when no control message nor name buffers are provided.
+ if msg.ControlLen == 0 && msg.NameLen == 0 {
+ n, mflags, _, _, cms, err := s.RecvMsg(t, dst, int(flags), haveDeadline, deadline, false, 0)
+ if err != nil {
+ return 0, syserror.ConvertIntr(err.ToError(), kernel.ERESTARTSYS)
+ }
+ if !cms.Unix.Empty() {
+ mflags |= linux.MSG_CTRUNC
+ cms.Release()
+ }
+
+ if int(msg.Flags) != mflags {
+ // Copy out the flags to the caller.
+ if _, err := t.CopyOut(msgPtr+flagsOffset, int32(mflags)); err != nil {
+ return 0, err
+ }
+ }
+
+ return uintptr(n), nil
+ }
+
+ if msg.ControlLen > maxControlLen {
+ return 0, syserror.ENOBUFS
+ }
+ n, mflags, sender, senderLen, cms, e := s.RecvMsg(t, dst, int(flags), haveDeadline, deadline, msg.NameLen != 0, msg.ControlLen)
+ if e != nil {
+ return 0, syserror.ConvertIntr(e.ToError(), kernel.ERESTARTSYS)
+ }
+ defer cms.Release()
+
+ controlData := make([]byte, 0, msg.ControlLen)
+ controlData = control.PackControlMessages(t, cms, controlData)
+
+ if cr, ok := s.(transport.Credentialer); ok && cr.Passcred() {
+ creds, _ := cms.Unix.Credentials.(control.SCMCredentials)
+ controlData, mflags = control.PackCredentials(t, creds, controlData, mflags)
+ }
+
+ if cms.Unix.Rights != nil {
+ controlData, mflags = control.PackRights(t, cms.Unix.Rights.(control.SCMRights), flags&linux.MSG_CMSG_CLOEXEC != 0, controlData, mflags)
+ }
+
+ // Copy the address to the caller.
+ if msg.NameLen != 0 {
+ if err := writeAddress(t, sender, senderLen, usermem.Addr(msg.Name), usermem.Addr(msgPtr+nameLenOffset)); err != nil {
+ return 0, err
+ }
+ }
+
+ // Copy the control data to the caller.
+ if _, err := t.CopyOut(msgPtr+controlLenOffset, uint64(len(controlData))); err != nil {
+ return 0, err
+ }
+ if len(controlData) > 0 {
+ if _, err := t.CopyOut(usermem.Addr(msg.Control), controlData); err != nil {
+ return 0, err
+ }
+ }
+
+ // Copy out the flags to the caller.
+ if _, err := t.CopyOut(msgPtr+flagsOffset, int32(mflags)); err != nil {
+ return 0, err
+ }
+
+ return uintptr(n), nil
+}
+
+// recvFrom is the implementation of the recvfrom syscall. It is called by
+// recvfrom and recv syscall handlers.
+func recvFrom(t *kernel.Task, fd int32, bufPtr usermem.Addr, bufLen uint64, flags int32, namePtr usermem.Addr, nameLenPtr usermem.Addr) (uintptr, error) {
+ if int(bufLen) < 0 {
+ return 0, syserror.EINVAL
+ }
+
+ // Reject flags that we don't handle yet.
+ if flags & ^(baseRecvFlags|linux.MSG_PEEK|linux.MSG_CONFIRM) != 0 {
+ return 0, syserror.EINVAL
+ }
+
+ // Get socket from the file descriptor.
+ file := t.GetFileVFS2(fd)
+ if file == nil {
+ return 0, syserror.EBADF
+ }
+ defer file.DecRef()
+
+ // Extract the socket.
+ s, ok := file.Impl().(socket.SocketVFS2)
+ if !ok {
+ return 0, syserror.ENOTSOCK
+ }
+
+ if (file.StatusFlags() & linux.SOCK_NONBLOCK) != 0 {
+ flags |= linux.MSG_DONTWAIT
+ }
+
+ dst, err := t.SingleIOSequence(bufPtr, int(bufLen), usermem.IOOpts{
+ AddressSpaceActive: true,
+ })
+ if err != nil {
+ return 0, err
+ }
+
+ var haveDeadline bool
+ var deadline ktime.Time
+ if dl := s.RecvTimeout(); dl > 0 {
+ deadline = t.Kernel().MonotonicClock().Now().Add(time.Duration(dl) * time.Nanosecond)
+ haveDeadline = true
+ } else if dl < 0 {
+ flags |= linux.MSG_DONTWAIT
+ }
+
+ n, _, sender, senderLen, cm, e := s.RecvMsg(t, dst, int(flags), haveDeadline, deadline, nameLenPtr != 0, 0)
+ cm.Release()
+ if e != nil {
+ return 0, syserror.ConvertIntr(e.ToError(), kernel.ERESTARTSYS)
+ }
+
+ // Copy the address to the caller.
+ if nameLenPtr != 0 {
+ if err := writeAddress(t, sender, senderLen, namePtr, nameLenPtr); err != nil {
+ return 0, err
+ }
+ }
+
+ return uintptr(n), nil
+}
+
+// RecvFrom implements the linux syscall recvfrom(2).
+func RecvFrom(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ fd := args[0].Int()
+ bufPtr := args[1].Pointer()
+ bufLen := args[2].Uint64()
+ flags := args[3].Int()
+ namePtr := args[4].Pointer()
+ nameLenPtr := args[5].Pointer()
+
+ n, err := recvFrom(t, fd, bufPtr, bufLen, flags, namePtr, nameLenPtr)
+ return n, nil, err
+}
+
+// SendMsg implements the linux syscall sendmsg(2).
+func SendMsg(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ fd := args[0].Int()
+ msgPtr := args[1].Pointer()
+ flags := args[2].Int()
+
+ if t.Arch().Width() != 8 {
+ // We only handle 64-bit for now.
+ return 0, nil, syserror.EINVAL
+ }
+
+ // Get socket from the file descriptor.
+ file := t.GetFileVFS2(fd)
+ if file == nil {
+ return 0, nil, syserror.EBADF
+ }
+ defer file.DecRef()
+
+ // Extract the socket.
+ s, ok := file.Impl().(socket.SocketVFS2)
+ if !ok {
+ return 0, nil, syserror.ENOTSOCK
+ }
+
+ // Reject flags that we don't handle yet.
+ if flags & ^(linux.MSG_DONTWAIT|linux.MSG_EOR|linux.MSG_MORE|linux.MSG_NOSIGNAL) != 0 {
+ return 0, nil, syserror.EINVAL
+ }
+
+ if (file.StatusFlags() & linux.SOCK_NONBLOCK) != 0 {
+ flags |= linux.MSG_DONTWAIT
+ }
+
+ n, err := sendSingleMsg(t, s, file, msgPtr, flags)
+ return n, nil, err
+}
+
+// SendMMsg implements the linux syscall sendmmsg(2).
+func SendMMsg(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ fd := args[0].Int()
+ msgPtr := args[1].Pointer()
+ vlen := args[2].Uint()
+ flags := args[3].Int()
+
+ if t.Arch().Width() != 8 {
+ // We only handle 64-bit for now.
+ return 0, nil, syserror.EINVAL
+ }
+
+ // Get socket from the file descriptor.
+ file := t.GetFileVFS2(fd)
+ if file == nil {
+ return 0, nil, syserror.EBADF
+ }
+ defer file.DecRef()
+
+ // Extract the socket.
+ s, ok := file.Impl().(socket.SocketVFS2)
+ if !ok {
+ return 0, nil, syserror.ENOTSOCK
+ }
+
+ // Reject flags that we don't handle yet.
+ if flags & ^(linux.MSG_DONTWAIT|linux.MSG_EOR|linux.MSG_MORE|linux.MSG_NOSIGNAL) != 0 {
+ return 0, nil, syserror.EINVAL
+ }
+
+ if (file.StatusFlags() & linux.SOCK_NONBLOCK) != 0 {
+ flags |= linux.MSG_DONTWAIT
+ }
+
+ var count uint32
+ var err error
+ for i := uint64(0); i < uint64(vlen); i++ {
+ mp, ok := msgPtr.AddLength(i * multipleMessageHeader64Len)
+ if !ok {
+ return 0, nil, syserror.EFAULT
+ }
+ var n uintptr
+ if n, err = sendSingleMsg(t, s, file, mp, flags); err != nil {
+ break
+ }
+
+ // Copy the received length to the caller.
+ lp, ok := mp.AddLength(messageHeader64Len)
+ if !ok {
+ return 0, nil, syserror.EFAULT
+ }
+ if _, err = t.CopyOut(lp, uint32(n)); err != nil {
+ break
+ }
+ count++
+ }
+
+ if count == 0 {
+ return 0, nil, err
+ }
+ return uintptr(count), nil, nil
+}
+
+func sendSingleMsg(t *kernel.Task, s socket.SocketVFS2, file *vfs.FileDescription, msgPtr usermem.Addr, flags int32) (uintptr, error) {
+ // Capture the message header.
+ var msg MessageHeader64
+ if err := CopyInMessageHeader64(t, msgPtr, &msg); err != nil {
+ return 0, err
+ }
+
+ var controlData []byte
+ if msg.ControlLen > 0 {
+ // Put an upper bound to prevent large allocations.
+ if msg.ControlLen > maxControlLen {
+ return 0, syserror.ENOBUFS
+ }
+ controlData = make([]byte, msg.ControlLen)
+ if _, err := t.CopyIn(usermem.Addr(msg.Control), &controlData); err != nil {
+ return 0, err
+ }
+ }
+
+ // Read the destination address if one is specified.
+ var to []byte
+ if msg.NameLen != 0 {
+ var err error
+ to, err = CaptureAddress(t, usermem.Addr(msg.Name), msg.NameLen)
+ if err != nil {
+ return 0, err
+ }
+ }
+
+ // Read data then call the sendmsg implementation.
+ if msg.IovLen > linux.UIO_MAXIOV {
+ return 0, syserror.EMSGSIZE
+ }
+ src, err := t.IovecsIOSequence(usermem.Addr(msg.Iov), int(msg.IovLen), usermem.IOOpts{
+ AddressSpaceActive: true,
+ })
+ if err != nil {
+ return 0, err
+ }
+
+ controlMessages, err := control.Parse(t, s, controlData)
+ if err != nil {
+ return 0, err
+ }
+
+ var haveDeadline bool
+ var deadline ktime.Time
+ if dl := s.SendTimeout(); dl > 0 {
+ deadline = t.Kernel().MonotonicClock().Now().Add(time.Duration(dl) * time.Nanosecond)
+ haveDeadline = true
+ } else if dl < 0 {
+ flags |= linux.MSG_DONTWAIT
+ }
+
+ // Call the syscall implementation.
+ n, e := s.SendMsg(t, src, to, int(flags), haveDeadline, deadline, controlMessages)
+ err = slinux.HandleIOErrorVFS2(t, n != 0, e.ToError(), kernel.ERESTARTSYS, "sendmsg", file)
+ if err != nil {
+ controlMessages.Release()
+ }
+ return uintptr(n), err
+}
+
+// sendTo is the implementation of the sendto syscall. It is called by sendto
+// and send syscall handlers.
+func sendTo(t *kernel.Task, fd int32, bufPtr usermem.Addr, bufLen uint64, flags int32, namePtr usermem.Addr, nameLen uint32) (uintptr, error) {
+ bl := int(bufLen)
+ if bl < 0 {
+ return 0, syserror.EINVAL
+ }
+
+ // Get socket from the file descriptor.
+ file := t.GetFileVFS2(fd)
+ if file == nil {
+ return 0, syserror.EBADF
+ }
+ defer file.DecRef()
+
+ // Extract the socket.
+ s, ok := file.Impl().(socket.SocketVFS2)
+ if !ok {
+ return 0, syserror.ENOTSOCK
+ }
+
+ if (file.StatusFlags() & linux.SOCK_NONBLOCK) != 0 {
+ flags |= linux.MSG_DONTWAIT
+ }
+
+ // Read the destination address if one is specified.
+ var to []byte
+ var err error
+ if namePtr != 0 {
+ to, err = CaptureAddress(t, namePtr, nameLen)
+ if err != nil {
+ return 0, err
+ }
+ }
+
+ src, err := t.SingleIOSequence(bufPtr, bl, usermem.IOOpts{
+ AddressSpaceActive: true,
+ })
+ if err != nil {
+ return 0, err
+ }
+
+ var haveDeadline bool
+ var deadline ktime.Time
+ if dl := s.SendTimeout(); dl > 0 {
+ deadline = t.Kernel().MonotonicClock().Now().Add(time.Duration(dl) * time.Nanosecond)
+ haveDeadline = true
+ } else if dl < 0 {
+ flags |= linux.MSG_DONTWAIT
+ }
+
+ // Call the syscall implementation.
+ n, e := s.SendMsg(t, src, to, int(flags), haveDeadline, deadline, socket.ControlMessages{Unix: control.New(t, s, nil)})
+ return uintptr(n), slinux.HandleIOErrorVFS2(t, n != 0, e.ToError(), kernel.ERESTARTSYS, "sendto", file)
+}
+
+// SendTo implements the linux syscall sendto(2).
+func SendTo(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ fd := args[0].Int()
+ bufPtr := args[1].Pointer()
+ bufLen := args[2].Uint64()
+ flags := args[3].Int()
+ namePtr := args[4].Pointer()
+ nameLen := args[5].Uint()
+
+ n, err := sendTo(t, fd, bufPtr, bufLen, flags, namePtr, nameLen)
+ return n, nil, err
+}
diff --git a/pkg/sentry/syscalls/linux/vfs2/xattr.go b/pkg/sentry/syscalls/linux/vfs2/xattr.go
index 89e9ff4d7..af455d5c1 100644
--- a/pkg/sentry/syscalls/linux/vfs2/xattr.go
+++ b/pkg/sentry/syscalls/linux/vfs2/xattr.go
@@ -51,7 +51,7 @@ func listxattr(t *kernel.Task, args arch.SyscallArguments, shouldFollowFinalSyml
}
defer tpop.Release()
- names, err := t.Kernel().VFS().ListxattrAt(t, t.Credentials(), &tpop.pop)
+ names, err := t.Kernel().VFS().ListxattrAt(t, t.Credentials(), &tpop.pop, uint64(size))
if err != nil {
return 0, nil, err
}
@@ -74,7 +74,7 @@ func Flistxattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sy
}
defer file.DecRef()
- names, err := file.Listxattr(t)
+ names, err := file.Listxattr(t, uint64(size))
if err != nil {
return 0, nil, err
}
@@ -116,7 +116,10 @@ func getxattr(t *kernel.Task, args arch.SyscallArguments, shouldFollowFinalSymli
return 0, nil, err
}
- value, err := t.Kernel().VFS().GetxattrAt(t, t.Credentials(), &tpop.pop, name)
+ value, err := t.Kernel().VFS().GetxattrAt(t, t.Credentials(), &tpop.pop, &vfs.GetxattrOptions{
+ Name: name,
+ Size: uint64(size),
+ })
if err != nil {
return 0, nil, err
}
@@ -145,7 +148,7 @@ func Fgetxattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys
return 0, nil, err
}
- value, err := file.Getxattr(t, name)
+ value, err := file.Getxattr(t, &vfs.GetxattrOptions{Name: name, Size: uint64(size)})
if err != nil {
return 0, nil, err
}
@@ -230,7 +233,7 @@ func Fsetxattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys
return 0, nil, err
}
- return 0, nil, file.Setxattr(t, vfs.SetxattrOptions{
+ return 0, nil, file.Setxattr(t, &vfs.SetxattrOptions{
Name: name,
Value: value,
Flags: uint32(flags),
diff --git a/pkg/sentry/vfs/anonfs.go b/pkg/sentry/vfs/anonfs.go
index d1f6dfb45..a64d86122 100644
--- a/pkg/sentry/vfs/anonfs.go
+++ b/pkg/sentry/vfs/anonfs.go
@@ -245,7 +245,7 @@ func (fs *anonFilesystem) BoundEndpointAt(ctx context.Context, rp *ResolvingPath
}
// ListxattrAt implements FilesystemImpl.ListxattrAt.
-func (fs *anonFilesystem) ListxattrAt(ctx context.Context, rp *ResolvingPath) ([]string, error) {
+func (fs *anonFilesystem) ListxattrAt(ctx context.Context, rp *ResolvingPath, size uint64) ([]string, error) {
if !rp.Done() {
return nil, syserror.ENOTDIR
}
@@ -253,7 +253,7 @@ func (fs *anonFilesystem) ListxattrAt(ctx context.Context, rp *ResolvingPath) ([
}
// GetxattrAt implements FilesystemImpl.GetxattrAt.
-func (fs *anonFilesystem) GetxattrAt(ctx context.Context, rp *ResolvingPath, name string) (string, error) {
+func (fs *anonFilesystem) GetxattrAt(ctx context.Context, rp *ResolvingPath, opts GetxattrOptions) (string, error) {
if !rp.Done() {
return "", syserror.ENOTDIR
}
diff --git a/pkg/sentry/vfs/file_description.go b/pkg/sentry/vfs/file_description.go
index 20c545fca..4fb9aea87 100644
--- a/pkg/sentry/vfs/file_description.go
+++ b/pkg/sentry/vfs/file_description.go
@@ -401,11 +401,11 @@ type FileDescriptionImpl interface {
Ioctl(ctx context.Context, uio usermem.IO, args arch.SyscallArguments) (uintptr, error)
// Listxattr returns all extended attribute names for the file.
- Listxattr(ctx context.Context) ([]string, error)
+ Listxattr(ctx context.Context, size uint64) ([]string, error)
// Getxattr returns the value associated with the given extended attribute
// for the file.
- Getxattr(ctx context.Context, name string) (string, error)
+ Getxattr(ctx context.Context, opts GetxattrOptions) (string, error)
// Setxattr changes the value associated with the given extended attribute
// for the file.
@@ -605,18 +605,23 @@ func (fd *FileDescription) Ioctl(ctx context.Context, uio usermem.IO, args arch.
// Listxattr returns all extended attribute names for the file represented by
// fd.
-func (fd *FileDescription) Listxattr(ctx context.Context) ([]string, error) {
+//
+// If the size of the list (including a NUL terminating byte after every entry)
+// would exceed size, ERANGE may be returned. Note that implementations
+// are free to ignore size entirely and return without error). In all cases,
+// if size is 0, the list should be returned without error, regardless of size.
+func (fd *FileDescription) Listxattr(ctx context.Context, size uint64) ([]string, error) {
if fd.opts.UseDentryMetadata {
vfsObj := fd.vd.mount.vfs
rp := vfsObj.getResolvingPath(auth.CredentialsFromContext(ctx), &PathOperation{
Root: fd.vd,
Start: fd.vd,
})
- names, err := fd.vd.mount.fs.impl.ListxattrAt(ctx, rp)
+ names, err := fd.vd.mount.fs.impl.ListxattrAt(ctx, rp, size)
vfsObj.putResolvingPath(rp)
return names, err
}
- names, err := fd.impl.Listxattr(ctx)
+ names, err := fd.impl.Listxattr(ctx, size)
if err == syserror.ENOTSUP {
// Linux doesn't actually return ENOTSUP in this case; instead,
// fs/xattr.c:vfs_listxattr() falls back to allowing the security
@@ -629,34 +634,39 @@ func (fd *FileDescription) Listxattr(ctx context.Context) ([]string, error) {
// Getxattr returns the value associated with the given extended attribute for
// the file represented by fd.
-func (fd *FileDescription) Getxattr(ctx context.Context, name string) (string, error) {
+//
+// If the size of the return value exceeds opts.Size, ERANGE may be returned
+// (note that implementations are free to ignore opts.Size entirely and return
+// without error). In all cases, if opts.Size is 0, the value should be
+// returned without error, regardless of size.
+func (fd *FileDescription) Getxattr(ctx context.Context, opts *GetxattrOptions) (string, error) {
if fd.opts.UseDentryMetadata {
vfsObj := fd.vd.mount.vfs
rp := vfsObj.getResolvingPath(auth.CredentialsFromContext(ctx), &PathOperation{
Root: fd.vd,
Start: fd.vd,
})
- val, err := fd.vd.mount.fs.impl.GetxattrAt(ctx, rp, name)
+ val, err := fd.vd.mount.fs.impl.GetxattrAt(ctx, rp, *opts)
vfsObj.putResolvingPath(rp)
return val, err
}
- return fd.impl.Getxattr(ctx, name)
+ return fd.impl.Getxattr(ctx, *opts)
}
// Setxattr changes the value associated with the given extended attribute for
// the file represented by fd.
-func (fd *FileDescription) Setxattr(ctx context.Context, opts SetxattrOptions) error {
+func (fd *FileDescription) Setxattr(ctx context.Context, opts *SetxattrOptions) error {
if fd.opts.UseDentryMetadata {
vfsObj := fd.vd.mount.vfs
rp := vfsObj.getResolvingPath(auth.CredentialsFromContext(ctx), &PathOperation{
Root: fd.vd,
Start: fd.vd,
})
- err := fd.vd.mount.fs.impl.SetxattrAt(ctx, rp, opts)
+ err := fd.vd.mount.fs.impl.SetxattrAt(ctx, rp, *opts)
vfsObj.putResolvingPath(rp)
return err
}
- return fd.impl.Setxattr(ctx, opts)
+ return fd.impl.Setxattr(ctx, *opts)
}
// Removexattr removes the given extended attribute from the file represented
diff --git a/pkg/sentry/vfs/file_description_impl_util.go b/pkg/sentry/vfs/file_description_impl_util.go
index d45e602ce..f4c111926 100644
--- a/pkg/sentry/vfs/file_description_impl_util.go
+++ b/pkg/sentry/vfs/file_description_impl_util.go
@@ -130,14 +130,14 @@ func (FileDescriptionDefaultImpl) Ioctl(ctx context.Context, uio usermem.IO, arg
// Listxattr implements FileDescriptionImpl.Listxattr analogously to
// inode_operations::listxattr == NULL in Linux.
-func (FileDescriptionDefaultImpl) Listxattr(ctx context.Context) ([]string, error) {
+func (FileDescriptionDefaultImpl) Listxattr(ctx context.Context, size uint64) ([]string, error) {
// This isn't exactly accurate; see FileDescription.Listxattr.
return nil, syserror.ENOTSUP
}
// Getxattr implements FileDescriptionImpl.Getxattr analogously to
// inode::i_opflags & IOP_XATTR == 0 in Linux.
-func (FileDescriptionDefaultImpl) Getxattr(ctx context.Context, name string) (string, error) {
+func (FileDescriptionDefaultImpl) Getxattr(ctx context.Context, opts GetxattrOptions) (string, error) {
return "", syserror.ENOTSUP
}
diff --git a/pkg/sentry/vfs/filesystem.go b/pkg/sentry/vfs/filesystem.go
index bef1bd312..a537a29d1 100644
--- a/pkg/sentry/vfs/filesystem.go
+++ b/pkg/sentry/vfs/filesystem.go
@@ -442,7 +442,13 @@ type FilesystemImpl interface {
// - If extended attributes are not supported by the filesystem,
// ListxattrAt returns nil. (See FileDescription.Listxattr for an
// explanation.)
- ListxattrAt(ctx context.Context, rp *ResolvingPath) ([]string, error)
+ //
+ // - If the size of the list (including a NUL terminating byte after every
+ // entry) would exceed size, ERANGE may be returned. Note that
+ // implementations are free to ignore size entirely and return without
+ // error). In all cases, if size is 0, the list should be returned without
+ // error, regardless of size.
+ ListxattrAt(ctx context.Context, rp *ResolvingPath, size uint64) ([]string, error)
// GetxattrAt returns the value associated with the given extended
// attribute for the file at rp.
@@ -451,7 +457,15 @@ type FilesystemImpl interface {
//
// - If extended attributes are not supported by the filesystem, GetxattrAt
// returns ENOTSUP.
- GetxattrAt(ctx context.Context, rp *ResolvingPath, name string) (string, error)
+ //
+ // - If an extended attribute named opts.Name does not exist, ENODATA is
+ // returned.
+ //
+ // - If the size of the return value exceeds opts.Size, ERANGE may be
+ // returned (note that implementations are free to ignore opts.Size entirely
+ // and return without error). In all cases, if opts.Size is 0, the value
+ // should be returned without error, regardless of size.
+ GetxattrAt(ctx context.Context, rp *ResolvingPath, opts GetxattrOptions) (string, error)
// SetxattrAt changes the value associated with the given extended
// attribute for the file at rp.
@@ -460,6 +474,10 @@ type FilesystemImpl interface {
//
// - If extended attributes are not supported by the filesystem, SetxattrAt
// returns ENOTSUP.
+ //
+ // - If XATTR_CREATE is set in opts.Flag and opts.Name already exists,
+ // EEXIST is returned. If XATTR_REPLACE is set and opts.Name does not exist,
+ // ENODATA is returned.
SetxattrAt(ctx context.Context, rp *ResolvingPath, opts SetxattrOptions) error
// RemovexattrAt removes the given extended attribute from the file at rp.
@@ -468,6 +486,8 @@ type FilesystemImpl interface {
//
// - If extended attributes are not supported by the filesystem,
// RemovexattrAt returns ENOTSUP.
+ //
+ // - If name does not exist, ENODATA is returned.
RemovexattrAt(ctx context.Context, rp *ResolvingPath, name string) error
// BoundEndpointAt returns the Unix socket endpoint bound at the path rp.
diff --git a/pkg/sentry/vfs/memxattr/BUILD b/pkg/sentry/vfs/memxattr/BUILD
new file mode 100644
index 000000000..d8c4d27b9
--- /dev/null
+++ b/pkg/sentry/vfs/memxattr/BUILD
@@ -0,0 +1,15 @@
+load("//tools:defs.bzl", "go_library")
+
+package(licenses = ["notice"])
+
+go_library(
+ name = "memxattr",
+ srcs = ["xattr.go"],
+ visibility = ["//pkg/sentry:internal"],
+ deps = [
+ "//pkg/abi/linux",
+ "//pkg/sentry/vfs",
+ "//pkg/sync",
+ "//pkg/syserror",
+ ],
+)
diff --git a/pkg/sentry/vfs/memxattr/xattr.go b/pkg/sentry/vfs/memxattr/xattr.go
new file mode 100644
index 000000000..cc1e7d764
--- /dev/null
+++ b/pkg/sentry/vfs/memxattr/xattr.go
@@ -0,0 +1,102 @@
+// Copyright 2020 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package memxattr provides a default, in-memory extended attribute
+// implementation.
+package memxattr
+
+import (
+ "gvisor.dev/gvisor/pkg/abi/linux"
+ "gvisor.dev/gvisor/pkg/sentry/vfs"
+ "gvisor.dev/gvisor/pkg/sync"
+ "gvisor.dev/gvisor/pkg/syserror"
+)
+
+// SimpleExtendedAttributes implements extended attributes using a map of
+// names to values.
+//
+// +stateify savable
+type SimpleExtendedAttributes struct {
+ // mu protects the below fields.
+ mu sync.RWMutex `state:"nosave"`
+ xattrs map[string]string
+}
+
+// Getxattr returns the value at 'name'.
+func (x *SimpleExtendedAttributes) Getxattr(opts *vfs.GetxattrOptions) (string, error) {
+ x.mu.RLock()
+ value, ok := x.xattrs[opts.Name]
+ x.mu.RUnlock()
+ if !ok {
+ return "", syserror.ENODATA
+ }
+ // Check that the size of the buffer provided in getxattr(2) is large enough
+ // to contain the value.
+ if opts.Size != 0 && uint64(len(value)) > opts.Size {
+ return "", syserror.ERANGE
+ }
+ return value, nil
+}
+
+// Setxattr sets 'value' at 'name'.
+func (x *SimpleExtendedAttributes) Setxattr(opts *vfs.SetxattrOptions) error {
+ x.mu.Lock()
+ defer x.mu.Unlock()
+ if x.xattrs == nil {
+ if opts.Flags&linux.XATTR_REPLACE != 0 {
+ return syserror.ENODATA
+ }
+ x.xattrs = make(map[string]string)
+ }
+
+ _, ok := x.xattrs[opts.Name]
+ if ok && opts.Flags&linux.XATTR_CREATE != 0 {
+ return syserror.EEXIST
+ }
+ if !ok && opts.Flags&linux.XATTR_REPLACE != 0 {
+ return syserror.ENODATA
+ }
+
+ x.xattrs[opts.Name] = opts.Value
+ return nil
+}
+
+// Listxattr returns all names in xattrs.
+func (x *SimpleExtendedAttributes) Listxattr(size uint64) ([]string, error) {
+ // Keep track of the size of the buffer needed in listxattr(2) for the list.
+ listSize := 0
+ x.mu.RLock()
+ names := make([]string, 0, len(x.xattrs))
+ for n := range x.xattrs {
+ names = append(names, n)
+ // Add one byte per null terminator.
+ listSize += len(n) + 1
+ }
+ x.mu.RUnlock()
+ if size != 0 && uint64(listSize) > size {
+ return nil, syserror.ERANGE
+ }
+ return names, nil
+}
+
+// Removexattr removes the xattr at 'name'.
+func (x *SimpleExtendedAttributes) Removexattr(name string) error {
+ x.mu.Lock()
+ defer x.mu.Unlock()
+ if _, ok := x.xattrs[name]; !ok {
+ return syserror.ENODATA
+ }
+ delete(x.xattrs, name)
+ return nil
+}
diff --git a/pkg/sentry/vfs/options.go b/pkg/sentry/vfs/options.go
index 2f04bf882..534528ce6 100644
--- a/pkg/sentry/vfs/options.go
+++ b/pkg/sentry/vfs/options.go
@@ -132,6 +132,20 @@ type SetStatOptions struct {
Stat linux.Statx
}
+// GetxattrOptions contains options to VirtualFilesystem.GetxattrAt(),
+// FilesystemImpl.GetxattrAt(), FileDescription.Getxattr(), and
+// FileDescriptionImpl.Getxattr().
+type GetxattrOptions struct {
+ // Name is the name of the extended attribute to retrieve.
+ Name string
+
+ // Size is the maximum value size that the caller will tolerate. If the value
+ // is larger than size, getxattr methods may return ERANGE, but they are also
+ // free to ignore the hint entirely (i.e. the value returned may be larger
+ // than size). All size checking is done independently at the syscall layer.
+ Size uint64
+}
+
// SetxattrOptions contains options to VirtualFilesystem.SetxattrAt(),
// FilesystemImpl.SetxattrAt(), FileDescription.Setxattr(), and
// FileDescriptionImpl.Setxattr().
diff --git a/pkg/sentry/vfs/vfs.go b/pkg/sentry/vfs/vfs.go
index 720b90d8f..f592913d5 100644
--- a/pkg/sentry/vfs/vfs.go
+++ b/pkg/sentry/vfs/vfs.go
@@ -680,10 +680,10 @@ func (vfs *VirtualFilesystem) UnlinkAt(ctx context.Context, creds *auth.Credenti
// ListxattrAt returns all extended attribute names for the file at the given
// path.
-func (vfs *VirtualFilesystem) ListxattrAt(ctx context.Context, creds *auth.Credentials, pop *PathOperation) ([]string, error) {
+func (vfs *VirtualFilesystem) ListxattrAt(ctx context.Context, creds *auth.Credentials, pop *PathOperation, size uint64) ([]string, error) {
rp := vfs.getResolvingPath(creds, pop)
for {
- names, err := rp.mount.fs.impl.ListxattrAt(ctx, rp)
+ names, err := rp.mount.fs.impl.ListxattrAt(ctx, rp, size)
if err == nil {
vfs.putResolvingPath(rp)
return names, nil
@@ -705,10 +705,10 @@ func (vfs *VirtualFilesystem) ListxattrAt(ctx context.Context, creds *auth.Crede
// GetxattrAt returns the value associated with the given extended attribute
// for the file at the given path.
-func (vfs *VirtualFilesystem) GetxattrAt(ctx context.Context, creds *auth.Credentials, pop *PathOperation, name string) (string, error) {
+func (vfs *VirtualFilesystem) GetxattrAt(ctx context.Context, creds *auth.Credentials, pop *PathOperation, opts *GetxattrOptions) (string, error) {
rp := vfs.getResolvingPath(creds, pop)
for {
- val, err := rp.mount.fs.impl.GetxattrAt(ctx, rp, name)
+ val, err := rp.mount.fs.impl.GetxattrAt(ctx, rp, *opts)
if err == nil {
vfs.putResolvingPath(rp)
return val, nil
diff --git a/pkg/state/state.go b/pkg/state/state.go
index dbe507ab4..03ae2dbb0 100644
--- a/pkg/state/state.go
+++ b/pkg/state/state.go
@@ -241,10 +241,7 @@ func Register(name string, instance interface{}, fns Fns) {
//
// This function is used by the stateify tool.
func IsZeroValue(val interface{}) bool {
- if val == nil {
- return true
- }
- return reflect.DeepEqual(val, reflect.Zero(reflect.TypeOf(val)).Interface())
+ return val == nil || reflect.ValueOf(val).Elem().IsZero()
}
// step captures one encoding / decoding step. On each step, there is up to one
diff --git a/pkg/tcpip/header/eth_test.go b/pkg/tcpip/header/eth_test.go
index 7a0014ad9..14413f2ce 100644
--- a/pkg/tcpip/header/eth_test.go
+++ b/pkg/tcpip/header/eth_test.go
@@ -88,7 +88,7 @@ func TestEthernetAddressFromMulticastIPv4Address(t *testing.T) {
for _, test := range tests {
t.Run(test.name, func(t *testing.T) {
if got := EthernetAddressFromMulticastIPv4Address(test.addr); got != test.expectedLinkAddr {
- t.Fatalf("got EthernetAddressFromMulticastIPv4Address(%s) = %s, want = %s", got, test.expectedLinkAddr)
+ t.Fatalf("got EthernetAddressFromMulticastIPv4Address(%s) = %s, want = %s", test.addr, got, test.expectedLinkAddr)
}
})
}
diff --git a/pkg/tcpip/header/ndp_test.go b/pkg/tcpip/header/ndp_test.go
index 1cb9f5dc8..969f8f1e8 100644
--- a/pkg/tcpip/header/ndp_test.go
+++ b/pkg/tcpip/header/ndp_test.go
@@ -115,7 +115,7 @@ func TestNDPNeighborAdvert(t *testing.T) {
// Make sure flags got updated in the backing buffer.
if got := b[ndpNAFlagsOffset]; got != 64 {
- t.Errorf("got flags byte = %d, want = 64")
+ t.Errorf("got flags byte = %d, want = 64", got)
}
}
diff --git a/pkg/tcpip/link/fdbased/endpoint.go b/pkg/tcpip/link/fdbased/endpoint.go
index 7198742b7..b857ce9d0 100644
--- a/pkg/tcpip/link/fdbased/endpoint.go
+++ b/pkg/tcpip/link/fdbased/endpoint.go
@@ -91,7 +91,7 @@ func (p PacketDispatchMode) String() string {
case PacketMMap:
return "PacketMMap"
default:
- return fmt.Sprintf("unknown packet dispatch mode %v", p)
+ return fmt.Sprintf("unknown packet dispatch mode '%d'", p)
}
}
diff --git a/pkg/tcpip/network/arp/arp_test.go b/pkg/tcpip/network/arp/arp_test.go
index b3e239ac7..1646d9cde 100644
--- a/pkg/tcpip/network/arp/arp_test.go
+++ b/pkg/tcpip/network/arp/arp_test.go
@@ -138,7 +138,8 @@ func TestDirectRequest(t *testing.T) {
// Sleep tests are gross, but this will only potentially flake
// if there's a bug. If there is no bug this will reliably
// succeed.
- ctx, _ := context.WithTimeout(context.Background(), 100*time.Millisecond)
+ ctx, cancel := context.WithTimeout(context.Background(), 100*time.Millisecond)
+ defer cancel()
if pkt, ok := c.linkEP.ReadContext(ctx); ok {
t.Errorf("stackAddrBad: unexpected packet sent, Proto=%v", pkt.Proto)
}
diff --git a/pkg/tcpip/stack/ndp_test.go b/pkg/tcpip/stack/ndp_test.go
index 27dc8baf9..acb2d4731 100644
--- a/pkg/tcpip/stack/ndp_test.go
+++ b/pkg/tcpip/stack/ndp_test.go
@@ -1959,7 +1959,7 @@ func TestAutoGenAddrDeprecateFromPI(t *testing.T) {
// addr2 is deprecated but if explicitly requested, it should be used.
fullAddr2 := tcpip.FullAddress{Addr: addr2.Address, NIC: nicID}
if got := addrForNewConnectionWithAddr(t, s, fullAddr2); got != addr2.Address {
- t.Errorf("got addrForNewConnectionWithAddr(_, _, %+v) = %s, want = %s", got, addr2.Address)
+ t.Errorf("got addrForNewConnectionWithAddr(_, _, %+v) = %s, want = %s", fullAddr2, got, addr2.Address)
}
// Another PI w/ 0 preferred lifetime should not result in a deprecation
@@ -1972,7 +1972,7 @@ func TestAutoGenAddrDeprecateFromPI(t *testing.T) {
}
expectPrimaryAddr(addr1)
if got := addrForNewConnectionWithAddr(t, s, fullAddr2); got != addr2.Address {
- t.Errorf("got addrForNewConnectionWithAddr(_, _, %+v) = %s, want = %s", got, addr2.Address)
+ t.Errorf("got addrForNewConnectionWithAddr(_, _, %+v) = %s, want = %s", fullAddr2, got, addr2.Address)
}
// Refresh lifetimes of addr generated from prefix2.
@@ -2084,7 +2084,7 @@ func TestAutoGenAddrTimerDeprecation(t *testing.T) {
// addr1 is deprecated but if explicitly requested, it should be used.
fullAddr1 := tcpip.FullAddress{Addr: addr1.Address, NIC: nicID}
if got := addrForNewConnectionWithAddr(t, s, fullAddr1); got != addr1.Address {
- t.Errorf("got addrForNewConnectionWithAddr(_, _, %+v) = %s, want = %s", got, addr1.Address)
+ t.Errorf("got addrForNewConnectionWithAddr(_, _, %+v) = %s, want = %s", fullAddr1, got, addr1.Address)
}
// Refresh valid lifetime for addr of prefix1, w/ 0 preferred lifetime to make
@@ -2097,7 +2097,7 @@ func TestAutoGenAddrTimerDeprecation(t *testing.T) {
}
expectPrimaryAddr(addr2)
if got := addrForNewConnectionWithAddr(t, s, fullAddr1); got != addr1.Address {
- t.Errorf("got addrForNewConnectionWithAddr(_, _, %+v) = %s, want = %s", got, addr1.Address)
+ t.Errorf("got addrForNewConnectionWithAddr(_, _, %+v) = %s, want = %s", fullAddr1, got, addr1.Address)
}
// Refresh lifetimes for addr of prefix1.
@@ -2121,7 +2121,7 @@ func TestAutoGenAddrTimerDeprecation(t *testing.T) {
// addr2 should be the primary endpoint now since it is not deprecated.
expectPrimaryAddr(addr2)
if got := addrForNewConnectionWithAddr(t, s, fullAddr1); got != addr1.Address {
- t.Errorf("got addrForNewConnectionWithAddr(_, _, %+v) = %s, want = %s", got, addr1.Address)
+ t.Errorf("got addrForNewConnectionWithAddr(_, _, %+v) = %s, want = %s", fullAddr1, got, addr1.Address)
}
// Wait for addr of prefix1 to be invalidated.
@@ -2564,7 +2564,7 @@ func TestAutoGenAddrAfterRemoval(t *testing.T) {
AddressWithPrefix: addr2,
}
if err := s.AddProtocolAddressWithOptions(nicID, protoAddr2, stack.FirstPrimaryEndpoint); err != nil {
- t.Fatalf("AddProtocolAddressWithOptions(%d, %+v, %d, %s) = %s", nicID, protoAddr2, stack.FirstPrimaryEndpoint, err)
+ t.Fatalf("AddProtocolAddressWithOptions(%d, %+v, %d) = %s", nicID, protoAddr2, stack.FirstPrimaryEndpoint, err)
}
// addr2 should be more preferred now since it is at the front of the primary
// list.
@@ -3483,7 +3483,8 @@ func TestRouterSolicitation(t *testing.T) {
e.Endpoint.LinkEPCapabilities |= stack.CapabilityResolutionRequired
waitForPkt := func(timeout time.Duration) {
t.Helper()
- ctx, _ := context.WithTimeout(context.Background(), timeout)
+ ctx, cancel := context.WithTimeout(context.Background(), timeout)
+ defer cancel()
p, ok := e.ReadContext(ctx)
if !ok {
t.Fatal("timed out waiting for packet")
@@ -3513,7 +3514,8 @@ func TestRouterSolicitation(t *testing.T) {
}
waitForNothing := func(timeout time.Duration) {
t.Helper()
- ctx, _ := context.WithTimeout(context.Background(), timeout)
+ ctx, cancel := context.WithTimeout(context.Background(), timeout)
+ defer cancel()
if _, ok := e.ReadContext(ctx); ok {
t.Fatal("unexpectedly got a packet")
}
diff --git a/pkg/tcpip/stack/stack_test.go b/pkg/tcpip/stack/stack_test.go
index 3f8a2a095..c7634ceb1 100644
--- a/pkg/tcpip/stack/stack_test.go
+++ b/pkg/tcpip/stack/stack_test.go
@@ -1445,19 +1445,19 @@ func TestOutgoingBroadcastWithEmptyRouteTable(t *testing.T) {
protoAddr := tcpip.ProtocolAddress{Protocol: fakeNetNumber, AddressWithPrefix: tcpip.AddressWithPrefix{header.IPv4Any, 0}}
if err := s.AddProtocolAddress(1, protoAddr); err != nil {
- t.Fatalf("AddProtocolAddress(1, %s) failed: %s", protoAddr, err)
+ t.Fatalf("AddProtocolAddress(1, %v) failed: %v", protoAddr, err)
}
r, err := s.FindRoute(1, header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, false /* multicastLoop */)
if err != nil {
- t.Fatalf("FindRoute(1, %s, %s, %d) failed: %s", header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, err)
+ t.Fatalf("FindRoute(1, %v, %v, %d) failed: %v", header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, err)
}
if err := verifyRoute(r, stack.Route{LocalAddress: header.IPv4Any, RemoteAddress: header.IPv4Broadcast}); err != nil {
- t.Errorf("FindRoute(1, %s, %s, %d) returned unexpected Route: %s)", header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, err)
+ t.Errorf("FindRoute(1, %v, %v, %d) returned unexpected Route: %v", header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, err)
}
// If the NIC doesn't exist, it won't work.
if _, err := s.FindRoute(2, header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, false /* multicastLoop */); err != tcpip.ErrNetworkUnreachable {
- t.Fatalf("got FindRoute(2, %s, %s, %d) = %s want = %s", header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, err, tcpip.ErrNetworkUnreachable)
+ t.Fatalf("got FindRoute(2, %v, %v, %d) = %v want = %v", header.IPv4Any, header.IPv4Broadcast, fakeNetNumber, err, tcpip.ErrNetworkUnreachable)
}
}
@@ -1483,12 +1483,12 @@ func TestOutgoingBroadcastWithRouteTable(t *testing.T) {
}
nic1ProtoAddr := tcpip.ProtocolAddress{fakeNetNumber, nic1Addr}
if err := s.AddProtocolAddress(1, nic1ProtoAddr); err != nil {
- t.Fatalf("AddProtocolAddress(1, %s) failed: %s", nic1ProtoAddr, err)
+ t.Fatalf("AddProtocolAddress(1, %v) failed: %v", nic1ProtoAddr, err)
}
nic2ProtoAddr := tcpip.ProtocolAddress{fakeNetNumber, nic2Addr}
if err := s.AddProtocolAddress(2, nic2ProtoAddr); err != nil {
- t.Fatalf("AddAddress(2, %s) failed: %s", nic2ProtoAddr, err)
+ t.Fatalf("AddAddress(2, %v) failed: %v", nic2ProtoAddr, err)
}
// Set the initial route table.
@@ -1503,10 +1503,10 @@ func TestOutgoingBroadcastWithRouteTable(t *testing.T) {
// When an interface is given, the route for a broadcast goes through it.
r, err := s.FindRoute(1, nic1Addr.Address, header.IPv4Broadcast, fakeNetNumber, false /* multicastLoop */)
if err != nil {
- t.Fatalf("FindRoute(1, %s, %s, %d) failed: %s", nic1Addr.Address, header.IPv4Broadcast, fakeNetNumber, err)
+ t.Fatalf("FindRoute(1, %v, %v, %d) failed: %v", nic1Addr.Address, header.IPv4Broadcast, fakeNetNumber, err)
}
if err := verifyRoute(r, stack.Route{LocalAddress: nic1Addr.Address, RemoteAddress: header.IPv4Broadcast}); err != nil {
- t.Errorf("FindRoute(1, %s, %s, %d) returned unexpected Route: %s)", nic1Addr.Address, header.IPv4Broadcast, fakeNetNumber, err)
+ t.Errorf("FindRoute(1, %v, %v, %d) returned unexpected Route: %v", nic1Addr.Address, header.IPv4Broadcast, fakeNetNumber, err)
}
// When an interface is not given, it consults the route table.
@@ -2399,7 +2399,7 @@ func TestNICContextPreservation(t *testing.T) {
t.Fatalf("got nicinfos[%d] = _, %t, want _, true; nicinfos = %+v", id, ok, nicinfos)
}
if got, want := nicinfo.Context == test.want, true; got != want {
- t.Fatal("got nicinfo.Context == ctx = %t, want %t; nicinfo.Context = %p, ctx = %p", got, want, nicinfo.Context, test.want)
+ t.Fatalf("got nicinfo.Context == ctx = %t, want %t; nicinfo.Context = %p, ctx = %p", got, want, nicinfo.Context, test.want)
}
})
}
@@ -2768,7 +2768,7 @@ func TestNewPEBOnPromotionToPermanent(t *testing.T) {
{
subnet, err := tcpip.NewSubnet("\x00", "\x00")
if err != nil {
- t.Fatalf("NewSubnet failed:", err)
+ t.Fatalf("NewSubnet failed: %v", err)
}
s.SetRouteTable([]tcpip.Route{{Destination: subnet, Gateway: "\x00", NIC: 1}})
}
@@ -2782,11 +2782,11 @@ func TestNewPEBOnPromotionToPermanent(t *testing.T) {
// permanentExpired kind.
r, err := s.FindRoute(1, "\x01", "\x02", fakeNetNumber, false)
if err != nil {
- t.Fatal("FindRoute failed:", err)
+ t.Fatalf("FindRoute failed: %v", err)
}
defer r.Release()
if err := s.RemoveAddress(1, "\x01"); err != nil {
- t.Fatalf("RemoveAddress failed:", err)
+ t.Fatalf("RemoveAddress failed: %v", err)
}
//
@@ -2798,7 +2798,7 @@ func TestNewPEBOnPromotionToPermanent(t *testing.T) {
// Add some other address with peb set to
// FirstPrimaryEndpoint.
if err := s.AddAddressWithOptions(1, fakeNetNumber, "\x03", stack.FirstPrimaryEndpoint); err != nil {
- t.Fatal("AddAddressWithOptions failed:", err)
+ t.Fatalf("AddAddressWithOptions failed: %v", err)
}
@@ -2806,7 +2806,7 @@ func TestNewPEBOnPromotionToPermanent(t *testing.T) {
// make sure the new peb was respected.
// (The address should just be promoted now).
if err := s.AddAddressWithOptions(1, fakeNetNumber, "\x01", ps); err != nil {
- t.Fatal("AddAddressWithOptions failed:", err)
+ t.Fatalf("AddAddressWithOptions failed: %v", err)
}
var primaryAddrs []tcpip.Address
for _, pa := range s.NICInfo()[1].ProtocolAddresses {
@@ -2839,11 +2839,11 @@ func TestNewPEBOnPromotionToPermanent(t *testing.T) {
// GetMainNICAddress; else, our original address
// should be returned.
if err := s.RemoveAddress(1, "\x03"); err != nil {
- t.Fatalf("RemoveAddress failed:", err)
+ t.Fatalf("RemoveAddress failed: %v", err)
}
addr, err = s.GetMainNICAddress(1, fakeNetNumber)
if err != nil {
- t.Fatal("s.GetMainNICAddress failed:", err)
+ t.Fatalf("s.GetMainNICAddress failed: %v", err)
}
if ps == stack.NeverPrimaryEndpoint {
if want := (tcpip.AddressWithPrefix{}); addr != want {
diff --git a/pkg/tcpip/tcpip_test.go b/pkg/tcpip/tcpip_test.go
index 8c0aacffa..1c8e2bc34 100644
--- a/pkg/tcpip/tcpip_test.go
+++ b/pkg/tcpip/tcpip_test.go
@@ -218,7 +218,7 @@ func TestAddressWithPrefixSubnet(t *testing.T) {
gotSubnet := ap.Subnet()
wantSubnet, err := NewSubnet(tt.subnetAddr, tt.subnetMask)
if err != nil {
- t.Error("NewSubnet(%q, %q) failed: %s", tt.subnetAddr, tt.subnetMask, err)
+ t.Errorf("NewSubnet(%q, %q) failed: %s", tt.subnetAddr, tt.subnetMask, err)
continue
}
if gotSubnet != wantSubnet {
diff --git a/pkg/tcpip/transport/tcp/tcp_test.go b/pkg/tcpip/transport/tcp/tcp_test.go
index 32d0af6c4..29301a45c 100644
--- a/pkg/tcpip/transport/tcp/tcp_test.go
+++ b/pkg/tcpip/transport/tcp/tcp_test.go
@@ -284,7 +284,7 @@ func TestTCPResetSentForACKWhenNotUsingSynCookies(t *testing.T) {
// are released instantly on Close.
tcpTW := tcpip.TCPTimeWaitTimeoutOption(1 * time.Millisecond)
if err := c.Stack().SetTransportProtocolOption(tcp.ProtocolNumber, tcpTW); err != nil {
- t.Fatalf("e.stack.SetTransportProtocolOption(%d, %s) = %s", tcp.ProtocolNumber, tcpTW, err)
+ t.Fatalf("e.stack.SetTransportProtocolOption(%d, %v) = %v", tcp.ProtocolNumber, tcpTW, err)
}
c.EP.Close()
@@ -5607,7 +5607,7 @@ func TestReceiveBufferAutoTuningApplicationLimited(t *testing.T) {
return
}
if w := tcp.WindowSize(); w == 0 || w > uint16(wantRcvWnd) {
- t.Errorf("expected a non-zero window: got %d, want <= wantRcvWnd", w, wantRcvWnd)
+ t.Errorf("expected a non-zero window: got %d, want <= wantRcvWnd", w)
}
},
))
diff --git a/pkg/tcpip/transport/tcp/testing/context/context.go b/pkg/tcpip/transport/tcp/testing/context/context.go
index d4f6bc635..431ab4e6b 100644
--- a/pkg/tcpip/transport/tcp/testing/context/context.go
+++ b/pkg/tcpip/transport/tcp/testing/context/context.go
@@ -217,7 +217,8 @@ func (c *Context) Stack() *stack.Stack {
func (c *Context) CheckNoPacketTimeout(errMsg string, wait time.Duration) {
c.t.Helper()
- ctx, _ := context.WithTimeout(context.Background(), wait)
+ ctx, cancel := context.WithTimeout(context.Background(), wait)
+ defer cancel()
if _, ok := c.linkEP.ReadContext(ctx); ok {
c.t.Fatal(errMsg)
}
@@ -235,7 +236,8 @@ func (c *Context) CheckNoPacket(errMsg string) {
func (c *Context) GetPacket() []byte {
c.t.Helper()
- ctx, _ := context.WithTimeout(context.Background(), 2*time.Second)
+ ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
+ defer cancel()
p, ok := c.linkEP.ReadContext(ctx)
if !ok {
c.t.Fatalf("Packet wasn't written out")
@@ -486,7 +488,8 @@ func (c *Context) CreateV6Endpoint(v6only bool) {
func (c *Context) GetV6Packet() []byte {
c.t.Helper()
- ctx, _ := context.WithTimeout(context.Background(), 2*time.Second)
+ ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
+ defer cancel()
p, ok := c.linkEP.ReadContext(ctx)
if !ok {
c.t.Fatalf("Packet wasn't written out")
diff --git a/pkg/tcpip/transport/udp/udp_test.go b/pkg/tcpip/transport/udp/udp_test.go
index b3ee688b7..8acaa607a 100644
--- a/pkg/tcpip/transport/udp/udp_test.go
+++ b/pkg/tcpip/transport/udp/udp_test.go
@@ -358,7 +358,8 @@ func (c *testContext) createEndpointForFlow(flow testFlow) {
func (c *testContext) getPacketAndVerify(flow testFlow, checkers ...checker.NetworkChecker) []byte {
c.t.Helper()
- ctx, _ := context.WithTimeout(context.Background(), 2*time.Second)
+ ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
+ defer cancel()
p, ok := c.linkEP.ReadContext(ctx)
if !ok {
c.t.Fatalf("Packet wasn't written out")
@@ -607,7 +608,7 @@ func testReadInternal(c *testContext, flow testFlow, packetShouldBeDropped, expe
// Check the peer address.
h := flow.header4Tuple(incoming)
if addr.Addr != h.srcAddr.Addr {
- c.t.Fatalf("unexpected remote address: got %s, want %s", addr.Addr, h.srcAddr)
+ c.t.Fatalf("unexpected remote address: got %s, want %v", addr.Addr, h.srcAddr)
}
// Check the payload.
@@ -1565,7 +1566,8 @@ func TestV4UnknownDestination(t *testing.T) {
}
c.injectPacket(tc.flow, payload)
if !tc.icmpRequired {
- ctx, _ := context.WithTimeout(context.Background(), time.Second)
+ ctx, cancel := context.WithTimeout(context.Background(), time.Second)
+ defer cancel()
if p, ok := c.linkEP.ReadContext(ctx); ok {
t.Fatalf("unexpected packet received: %+v", p)
}
@@ -1573,7 +1575,8 @@ func TestV4UnknownDestination(t *testing.T) {
}
// ICMP required.
- ctx, _ := context.WithTimeout(context.Background(), time.Second)
+ ctx, cancel := context.WithTimeout(context.Background(), time.Second)
+ defer cancel()
p, ok := c.linkEP.ReadContext(ctx)
if !ok {
t.Fatalf("packet wasn't written out")
@@ -1641,7 +1644,8 @@ func TestV6UnknownDestination(t *testing.T) {
}
c.injectPacket(tc.flow, payload)
if !tc.icmpRequired {
- ctx, _ := context.WithTimeout(context.Background(), time.Second)
+ ctx, cancel := context.WithTimeout(context.Background(), time.Second)
+ defer cancel()
if p, ok := c.linkEP.ReadContext(ctx); ok {
t.Fatalf("unexpected packet received: %+v", p)
}
@@ -1649,7 +1653,8 @@ func TestV6UnknownDestination(t *testing.T) {
}
// ICMP required.
- ctx, _ := context.WithTimeout(context.Background(), time.Second)
+ ctx, cancel := context.WithTimeout(context.Background(), time.Second)
+ defer cancel()
p, ok := c.linkEP.ReadContext(ctx)
if !ok {
t.Fatalf("packet wasn't written out")
diff --git a/pkg/usermem/usermem.go b/pkg/usermem/usermem.go
index d2f4403b0..cd6a0ea6b 100644
--- a/pkg/usermem/usermem.go
+++ b/pkg/usermem/usermem.go
@@ -29,9 +29,6 @@ import (
)
// IO provides access to the contents of a virtual memory space.
-//
-// FIXME(b/38173783): Implementations of IO cannot expect ctx to contain any
-// meaningful data.
type IO interface {
// CopyOut copies len(src) bytes from src to the memory mapped at addr. It
// returns the number of bytes copied. If the number of bytes copied is <