Merge release-20200921.0-66-g7d64bc1fd (automated)

11 files changed, 381 insertions, 133 deletions

diff --git a/pkg/sentry/kernel/kernel.go b/pkg/sentry/kernel/kernel.go
index 08bb5bd12..d6c21adb7 100644
--- a/pkg/sentry/kernel/kernel.go
+++ b/pkg/sentry/kernel/kernel.go
@@ -220,13 +220,18 @@ type Kernel struct {
 	// danglingEndpoints is used to save / restore tcpip.DanglingEndpoints.
 	danglingEndpoints struct{} `state:".([]tcpip.Endpoint)"`
 
-	// sockets is the list of all network sockets the system. Protected by
-	// extMu.
+	// sockets is the list of all network sockets in the system.
+	// Protected by extMu.
+	// TODO(gvisor.dev/issue/1624): Only used by VFS1.
 	sockets socketList
 
-	// nextSocketEntry is the next entry number to use in sockets. Protected
+	// socketsVFS2 records all network sockets in the system. Protected by
+	// extMu.
+	socketsVFS2 map[*vfs.FileDescription]*SocketRecord
+
+	// nextSocketRecord is the next entry number to use in sockets. Protected
 	// by extMu.
-	nextSocketEntry uint64
+	nextSocketRecord uint64
 
 	// deviceRegistry is used to save/restore device.SimpleDevices.
 	deviceRegistry struct{} `state:".(*device.Registry)"`
@@ -414,6 +419,8 @@ func (k *Kernel) Init(args InitKernelArgs) error {
 			return fmt.Errorf("failed to create sockfs mount: %v", err)
 		}
 		k.socketMount = socketMount
+
+		k.socketsVFS2 = make(map[*vfs.FileDescription]*SocketRecord)
 	}
 
 	return nil
@@ -1512,20 +1519,27 @@ func (k *Kernel) SupervisorContext() context.Context {
 	}
 }
 
-// SocketEntry represents a socket recorded in Kernel.sockets. It implements
+// SocketRecord represents a socket recorded in Kernel.socketsVFS2.
+//
+// +stateify savable
+type SocketRecord struct {
+	k        *Kernel
+	Sock     *refs.WeakRef        // TODO(gvisor.dev/issue/1624): Only used by VFS1.
+	SockVFS2 *vfs.FileDescription // Only used by VFS2.
+	ID       uint64               // Socket table entry number.
+}
+
+// SocketRecordVFS1 represents a socket recorded in Kernel.sockets. It implements
 // refs.WeakRefUser for sockets stored in the socket table.
 //
 // +stateify savable
-type SocketEntry struct {
+type SocketRecordVFS1 struct {
 	socketEntry
-	k        *Kernel
-	Sock     *refs.WeakRef
-	SockVFS2 *vfs.FileDescription
-	ID       uint64 // Socket table entry number.
+	SocketRecord
 }
 
 // WeakRefGone implements refs.WeakRefUser.WeakRefGone.
-func (s *SocketEntry) WeakRefGone(context.Context) {
+func (s *SocketRecordVFS1) WeakRefGone(context.Context) {
 	s.k.extMu.Lock()
 	s.k.sockets.Remove(s)
 	s.k.extMu.Unlock()
@@ -1536,9 +1550,14 @@ func (s *SocketEntry) WeakRefGone(context.Context) {
 // Precondition: Caller must hold a reference to sock.
 func (k *Kernel) RecordSocket(sock *fs.File) {
 	k.extMu.Lock()
-	id := k.nextSocketEntry
-	k.nextSocketEntry++
-	s := &SocketEntry{k: k, ID: id}
+	id := k.nextSocketRecord
+	k.nextSocketRecord++
+	s := &SocketRecordVFS1{
+		SocketRecord: SocketRecord{
+			k:  k,
+			ID: id,
+		},
+	}
 	s.Sock = refs.NewWeakRef(sock, s)
 	k.sockets.PushBack(s)
 	k.extMu.Unlock()
@@ -1550,29 +1569,45 @@ func (k *Kernel) RecordSocket(sock *fs.File) {
 // Precondition: Caller must hold a reference to sock.
 //
 // Note that the socket table will not hold a reference on the
-// vfs.FileDescription, because we do not support weak refs on VFS2 files.
+// vfs.FileDescription.
 func (k *Kernel) RecordSocketVFS2(sock *vfs.FileDescription) {
 	k.extMu.Lock()
-	id := k.nextSocketEntry
-	k.nextSocketEntry++
-	s := &SocketEntry{
+	if _, ok := k.socketsVFS2[sock]; ok {
+		panic(fmt.Sprintf("Socket %p added twice", sock))
+	}
+	id := k.nextSocketRecord
+	k.nextSocketRecord++
+	s := &SocketRecord{
 		k:        k,
 		ID:       id,
 		SockVFS2: sock,
 	}
-	k.sockets.PushBack(s)
+	k.socketsVFS2[sock] = s
+	k.extMu.Unlock()
+}
+
+// DeleteSocketVFS2 removes a VFS2 socket from the system-wide socket table.
+func (k *Kernel) DeleteSocketVFS2(sock *vfs.FileDescription) {
+	k.extMu.Lock()
+	delete(k.socketsVFS2, sock)
 	k.extMu.Unlock()
 }
 
 // ListSockets returns a snapshot of all sockets.
 //
-// Callers of ListSockets() in VFS2 should use SocketEntry.SockVFS2.TryIncRef()
+// Callers of ListSockets() in VFS2 should use SocketRecord.SockVFS2.TryIncRef()
 // to get a reference on a socket in the table.
-func (k *Kernel) ListSockets() []*SocketEntry {
+func (k *Kernel) ListSockets() []*SocketRecord {
 	k.extMu.Lock()
-	var socks []*SocketEntry
-	for s := k.sockets.Front(); s != nil; s = s.Next() {
-		socks = append(socks, s)
+	var socks []*SocketRecord
+	if VFS2Enabled {
+		for _, s := range k.socketsVFS2 {
+			socks = append(socks, s)
+		}
+	} else {
+		for s := k.sockets.Front(); s != nil; s = s.Next() {
+			socks = append(socks, &s.SocketRecord)
+		}
 	}
 	k.extMu.Unlock()
 	return socks
diff --git a/pkg/sentry/kernel/kernel_state_autogen.go b/pkg/sentry/kernel/kernel_state_autogen.go
index d0ff135d7..f20800960 100644
--- a/pkg/sentry/kernel/kernel_state_autogen.go
+++ b/pkg/sentry/kernel/kernel_state_autogen.go
@@ -297,7 +297,8 @@ func (x *Kernel) StateFields() []string {
 		"netlinkPorts",
 		"danglingEndpoints",
 		"sockets",
-		"nextSocketEntry",
+		"socketsVFS2",
+		"nextSocketRecord",
 		"deviceRegistry",
 		"DirentCacheLimiter",
 		"SpecialOpts",
@@ -317,7 +318,7 @@ func (x *Kernel) StateSave(m state.Sink) {
 	var danglingEndpoints []tcpip.Endpoint = x.saveDanglingEndpoints()
 	m.SaveValue(24, danglingEndpoints)
 	var deviceRegistry *device.Registry = x.saveDeviceRegistry()
-	m.SaveValue(27, deviceRegistry)
+	m.SaveValue(28, deviceRegistry)
 	m.Save(0, &x.featureSet)
 	m.Save(1, &x.timekeeper)
 	m.Save(2, &x.tasks)
@@ -343,15 +344,16 @@ func (x *Kernel) StateSave(m state.Sink) {
 	m.Save(22, &x.nextInotifyCookie)
 	m.Save(23, &x.netlinkPorts)
 	m.Save(25, &x.sockets)
-	m.Save(26, &x.nextSocketEntry)
-	m.Save(28, &x.DirentCacheLimiter)
-	m.Save(29, &x.SpecialOpts)
-	m.Save(30, &x.vfs)
-	m.Save(31, &x.hostMount)
-	m.Save(32, &x.pipeMount)
-	m.Save(33, &x.shmMount)
-	m.Save(34, &x.socketMount)
-	m.Save(35, &x.SleepForAddressSpaceActivation)
+	m.Save(26, &x.socketsVFS2)
+	m.Save(27, &x.nextSocketRecord)
+	m.Save(29, &x.DirentCacheLimiter)
+	m.Save(30, &x.SpecialOpts)
+	m.Save(31, &x.vfs)
+	m.Save(32, &x.hostMount)
+	m.Save(33, &x.pipeMount)
+	m.Save(34, &x.shmMount)
+	m.Save(35, &x.socketMount)
+	m.Save(36, &x.SleepForAddressSpaceActivation)
 }
 
 func (x *Kernel) afterLoad() {}
@@ -382,26 +384,26 @@ func (x *Kernel) StateLoad(m state.Source) {
 	m.Load(22, &x.nextInotifyCookie)
 	m.Load(23, &x.netlinkPorts)
 	m.Load(25, &x.sockets)
-	m.Load(26, &x.nextSocketEntry)
-	m.Load(28, &x.DirentCacheLimiter)
-	m.Load(29, &x.SpecialOpts)
-	m.Load(30, &x.vfs)
-	m.Load(31, &x.hostMount)
-	m.Load(32, &x.pipeMount)
-	m.Load(33, &x.shmMount)
-	m.Load(34, &x.socketMount)
-	m.Load(35, &x.SleepForAddressSpaceActivation)
+	m.Load(26, &x.socketsVFS2)
+	m.Load(27, &x.nextSocketRecord)
+	m.Load(29, &x.DirentCacheLimiter)
+	m.Load(30, &x.SpecialOpts)
+	m.Load(31, &x.vfs)
+	m.Load(32, &x.hostMount)
+	m.Load(33, &x.pipeMount)
+	m.Load(34, &x.shmMount)
+	m.Load(35, &x.socketMount)
+	m.Load(36, &x.SleepForAddressSpaceActivation)
 	m.LoadValue(24, new([]tcpip.Endpoint), func(y interface{}) { x.loadDanglingEndpoints(y.([]tcpip.Endpoint)) })
-	m.LoadValue(27, new(*device.Registry), func(y interface{}) { x.loadDeviceRegistry(y.(*device.Registry)) })
+	m.LoadValue(28, new(*device.Registry), func(y interface{}) { x.loadDeviceRegistry(y.(*device.Registry)) })
 }
 
-func (x *SocketEntry) StateTypeName() string {
-	return "pkg/sentry/kernel.SocketEntry"
+func (x *SocketRecord) StateTypeName() string {
+	return "pkg/sentry/kernel.SocketRecord"
 }
 
-func (x *SocketEntry) StateFields() []string {
+func (x *SocketRecord) StateFields() []string {
 	return []string{
-		"socketEntry",
 		"k",
 		"Sock",
 		"SockVFS2",
@@ -409,25 +411,49 @@ func (x *SocketEntry) StateFields() []string {
 	}
 }
 
-func (x *SocketEntry) beforeSave() {}
+func (x *SocketRecord) beforeSave() {}
 
-func (x *SocketEntry) StateSave(m state.Sink) {
+func (x *SocketRecord) StateSave(m state.Sink) {
+	x.beforeSave()
+	m.Save(0, &x.k)
+	m.Save(1, &x.Sock)
+	m.Save(2, &x.SockVFS2)
+	m.Save(3, &x.ID)
+}
+
+func (x *SocketRecord) afterLoad() {}
+
+func (x *SocketRecord) StateLoad(m state.Source) {
+	m.Load(0, &x.k)
+	m.Load(1, &x.Sock)
+	m.Load(2, &x.SockVFS2)
+	m.Load(3, &x.ID)
+}
+
+func (x *SocketRecordVFS1) StateTypeName() string {
+	return "pkg/sentry/kernel.SocketRecordVFS1"
+}
+
+func (x *SocketRecordVFS1) StateFields() []string {
+	return []string{
+		"socketEntry",
+		"SocketRecord",
+	}
+}
+
+func (x *SocketRecordVFS1) beforeSave() {}
+
+func (x *SocketRecordVFS1) StateSave(m state.Sink) {
 	x.beforeSave()
 	m.Save(0, &x.socketEntry)
-	m.Save(1, &x.k)
-	m.Save(2, &x.Sock)
-	m.Save(3, &x.SockVFS2)
-	m.Save(4, &x.ID)
+	m.Save(1, &x.SocketRecord)
 }
 
-func (x *SocketEntry) afterLoad() {}
+func (x *SocketRecordVFS1) afterLoad() {}
 
-func (x *SocketEntry) StateLoad(m state.Source) {
+func (x *SocketRecordVFS1) StateLoad(m state.Source) {
 	m.Load(0, &x.socketEntry)
-	m.Load(1, &x.k)
-	m.Load(2, &x.Sock)
-	m.Load(3, &x.SockVFS2)
-	m.Load(4, &x.ID)
+	m.Load(1, &x.SocketRecord)
 }
 
 func (x *pendingSignals) StateTypeName() string {
@@ -2264,7 +2290,8 @@ func init() {
 	state.Register((*FSContextRefs)(nil))
 	state.Register((*IPCNamespace)(nil))
 	state.Register((*Kernel)(nil))
-	state.Register((*SocketEntry)(nil))
+	state.Register((*SocketRecord)(nil))
+	state.Register((*SocketRecordVFS1)(nil))
 	state.Register((*pendingSignals)(nil))
 	state.Register((*pendingSignalQueue)(nil))
 	state.Register((*pendingSignal)(nil))
diff --git a/pkg/sentry/kernel/socket_list.go b/pkg/sentry/kernel/socket_list.go
index d2d4307a1..246fba405 100644
--- a/pkg/sentry/kernel/socket_list.go
+++ b/pkg/sentry/kernel/socket_list.go
@@ -13,7 +13,7 @@ type socketElementMapper struct{}
 // This default implementation should be inlined.
 //
 //go:nosplit
-func (socketElementMapper) linkerFor(elem *SocketEntry) *SocketEntry { return elem }
+func (socketElementMapper) linkerFor(elem *SocketRecordVFS1) *SocketRecordVFS1 { return elem }
 
 // List is an intrusive list. Entries can be added to or removed from the list
 // in O(1) time and with no additional memory allocations.
@@ -27,8 +27,8 @@ func (socketElementMapper) linkerFor(elem *SocketEntry) *SocketEntry { return el
 //
 // +stateify savable
 type socketList struct {
-	head *SocketEntry
-	tail *SocketEntry
+	head *SocketRecordVFS1
+	tail *SocketRecordVFS1
 }
 
 // Reset resets list l to the empty state.
@@ -43,12 +43,12 @@ func (l *socketList) Empty() bool {
 }
 
 // Front returns the first element of list l or nil.
-func (l *socketList) Front() *SocketEntry {
+func (l *socketList) Front() *SocketRecordVFS1 {
 	return l.head
 }
 
 // Back returns the last element of list l or nil.
-func (l *socketList) Back() *SocketEntry {
+func (l *socketList) Back() *SocketRecordVFS1 {
 	return l.tail
 }
 
@@ -63,7 +63,7 @@ func (l *socketList) Len() (count int) {
 }
 
 // PushFront inserts the element e at the front of list l.
-func (l *socketList) PushFront(e *SocketEntry) {
+func (l *socketList) PushFront(e *SocketRecordVFS1) {
 	linker := socketElementMapper{}.linkerFor(e)
 	linker.SetNext(l.head)
 	linker.SetPrev(nil)
@@ -77,7 +77,7 @@ func (l *socketList) PushFront(e *SocketEntry) {
 }
 
 // PushBack inserts the element e at the back of list l.
-func (l *socketList) PushBack(e *SocketEntry) {
+func (l *socketList) PushBack(e *SocketRecordVFS1) {
 	linker := socketElementMapper{}.linkerFor(e)
 	linker.SetNext(nil)
 	linker.SetPrev(l.tail)
@@ -106,7 +106,7 @@ func (l *socketList) PushBackList(m *socketList) {
 }
 
 // InsertAfter inserts e after b.
-func (l *socketList) InsertAfter(b, e *SocketEntry) {
+func (l *socketList) InsertAfter(b, e *SocketRecordVFS1) {
 	bLinker := socketElementMapper{}.linkerFor(b)
 	eLinker := socketElementMapper{}.linkerFor(e)
 
@@ -124,7 +124,7 @@ func (l *socketList) InsertAfter(b, e *SocketEntry) {
 }
 
 // InsertBefore inserts e before a.
-func (l *socketList) InsertBefore(a, e *SocketEntry) {
+func (l *socketList) InsertBefore(a, e *SocketRecordVFS1) {
 	aLinker := socketElementMapper{}.linkerFor(a)
 	eLinker := socketElementMapper{}.linkerFor(e)
 
@@ -141,7 +141,7 @@ func (l *socketList) InsertBefore(a, e *SocketEntry) {
 }
 
 // Remove removes e from l.
-func (l *socketList) Remove(e *SocketEntry) {
+func (l *socketList) Remove(e *SocketRecordVFS1) {
 	linker := socketElementMapper{}.linkerFor(e)
 	prev := linker.Prev()
 	next := linker.Next()
@@ -168,26 +168,26 @@ func (l *socketList) Remove(e *SocketEntry) {
 //
 // +stateify savable
 type socketEntry struct {
-	next *SocketEntry
-	prev *SocketEntry
+	next *SocketRecordVFS1
+	prev *SocketRecordVFS1
 }
 
 // Next returns the entry that follows e in the list.
-func (e *socketEntry) Next() *SocketEntry {
+func (e *socketEntry) Next() *SocketRecordVFS1 {
 	return e.next
 }
 
 // Prev returns the entry that precedes e in the list.
-func (e *socketEntry) Prev() *SocketEntry {
+func (e *socketEntry) Prev() *SocketRecordVFS1 {
 	return e.prev
 }
 
 // SetNext assigns 'entry' as the entry that follows e in the list.
-func (e *socketEntry) SetNext(elem *SocketEntry) {
+func (e *socketEntry) SetNext(elem *SocketRecordVFS1) {
 	e.next = elem
 }
 
 // SetPrev assigns 'entry' as the entry that precedes e in the list.
-func (e *socketEntry) SetPrev(elem *SocketEntry) {
+func (e *socketEntry) SetPrev(elem *SocketRecordVFS1) {
 	e.prev = elem
 }
diff --git a/pkg/sentry/socket/hostinet/socket_vfs2.go b/pkg/sentry/socket/hostinet/socket_vfs2.go
index 87b077e68..163af329b 100644
--- a/pkg/sentry/socket/hostinet/socket_vfs2.go
+++ b/pkg/sentry/socket/hostinet/socket_vfs2.go
@@ -78,6 +78,13 @@ func newVFS2Socket(t *kernel.Task, family int, stype linux.SockType, protocol in
 	return vfsfd, nil
 }
 
+// Release implements vfs.FileDescriptionImpl.Release.
+func (s *socketVFS2) Release(ctx context.Context) {
+	t := kernel.TaskFromContext(ctx)
+	t.Kernel().DeleteSocketVFS2(&s.vfsfd)
+	s.socketOpsCommon.Release(ctx)
+}
+
 // Readiness implements waiter.Waitable.Readiness.
 func (s *socketVFS2) Readiness(mask waiter.EventMask) waiter.EventMask {
 	return s.socketOpsCommon.Readiness(mask)
diff --git a/pkg/sentry/socket/netlink/socket_vfs2.go b/pkg/sentry/socket/netlink/socket_vfs2.go
index a38d25da9..c83b23242 100644
--- a/pkg/sentry/socket/netlink/socket_vfs2.go
+++ b/pkg/sentry/socket/netlink/socket_vfs2.go
@@ -82,6 +82,13 @@ func NewVFS2(t *kernel.Task, skType linux.SockType, protocol Protocol) (*SocketV
 	return fd, nil
 }
 
+// Release implements vfs.FileDescriptionImpl.Release.
+func (s *SocketVFS2) Release(ctx context.Context) {
+	t := kernel.TaskFromContext(ctx)
+	t.Kernel().DeleteSocketVFS2(&s.vfsfd)
+	s.socketOpsCommon.Release(ctx)
+}
+
 // Readiness implements waiter.Waitable.Readiness.
 func (s *SocketVFS2) Readiness(mask waiter.EventMask) waiter.EventMask {
 	return s.socketOpsCommon.Readiness(mask)
diff --git a/pkg/sentry/socket/netstack/netstack_vfs2.go b/pkg/sentry/socket/netstack/netstack_vfs2.go
index c0212ad76..4c6791fff 100644
--- a/pkg/sentry/socket/netstack/netstack_vfs2.go
+++ b/pkg/sentry/socket/netstack/netstack_vfs2.go
@@ -79,6 +79,13 @@ func NewVFS2(t *kernel.Task, family int, skType linux.SockType, protocol int, qu
 	return vfsfd, nil
 }
 
+// Release implements vfs.FileDescriptionImpl.Release.
+func (s *SocketVFS2) Release(ctx context.Context) {
+	t := kernel.TaskFromContext(ctx)
+	t.Kernel().DeleteSocketVFS2(&s.vfsfd)
+	s.socketOpsCommon.Release(ctx)
+}
+
 // Readiness implements waiter.Waitable.Readiness.
 func (s *SocketVFS2) Readiness(mask waiter.EventMask) waiter.EventMask {
 	return s.socketOpsCommon.Readiness(mask)
diff --git a/pkg/sentry/socket/unix/socket_refs.go b/pkg/sentry/socket/unix/socket_refs.go
index dababb85f..ea63dc659 100644
--- a/pkg/sentry/socket/unix/socket_refs.go
+++ b/pkg/sentry/socket/unix/socket_refs.go
@@ -11,7 +11,7 @@ import (
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
 // that we do not copy the entire object when passed as a format parameter.
-var socketOpsCommonownerType *socketOpsCommon
+var socketOperationsownerType *SocketOperations
 
 // Refs implements refs.RefCounter. It keeps a reference count using atomic
 // operations and calls the destructor when the count reaches zero.
@@ -25,7 +25,7 @@ var socketOpsCommonownerType *socketOpsCommon
 // without growing the size of Refs.
 //
 // +stateify savable
-type socketOpsCommonRefs struct {
+type socketOperationsRefs struct {
 	// refCount is composed of two fields:
 	//
 	//	[32-bit speculative references]:[32-bit real references]
@@ -36,7 +36,7 @@ type socketOpsCommonRefs struct {
 	refCount int64
 }
 
-func (r *socketOpsCommonRefs) finalize() {
+func (r *socketOperationsRefs) finalize() {
 	var note string
 	switch refs_vfs1.GetLeakMode() {
 	case refs_vfs1.NoLeakChecking:
@@ -45,20 +45,20 @@ func (r *socketOpsCommonRefs) finalize() {
 		note = "(Leak checker uninitialized): "
 	}
 	if n := r.ReadRefs(); n != 0 {
-		log.Warningf("%sRefs %p owned by %T garbage collected with ref count of %d (want 0)", note, r, socketOpsCommonownerType, n)
+		log.Warningf("%sRefs %p owned by %T garbage collected with ref count of %d (want 0)", note, r, socketOperationsownerType, n)
 	}
 }
 
 // EnableLeakCheck checks for reference leaks when Refs gets garbage collected.
-func (r *socketOpsCommonRefs) EnableLeakCheck() {
+func (r *socketOperationsRefs) EnableLeakCheck() {
 	if refs_vfs1.GetLeakMode() != refs_vfs1.NoLeakChecking {
-		runtime.SetFinalizer(r, (*socketOpsCommonRefs).finalize)
+		runtime.SetFinalizer(r, (*socketOperationsRefs).finalize)
 	}
 }
 
 // ReadRefs returns the current number of references. The returned count is
 // inherently racy and is unsafe to use without external synchronization.
-func (r *socketOpsCommonRefs) ReadRefs() int64 {
+func (r *socketOperationsRefs) ReadRefs() int64 {
 
 	return atomic.LoadInt64(&r.refCount) + 1
 }
@@ -66,9 +66,9 @@ func (r *socketOpsCommonRefs) ReadRefs() int64 {
 // IncRef implements refs.RefCounter.IncRef.
 //
 //go:nosplit
-func (r *socketOpsCommonRefs) IncRef() {
+func (r *socketOperationsRefs) IncRef() {
 	if v := atomic.AddInt64(&r.refCount, 1); v <= 0 {
-		panic(fmt.Sprintf("Incrementing non-positive ref count %p owned by %T", r, socketOpsCommonownerType))
+		panic(fmt.Sprintf("Incrementing non-positive ref count %p owned by %T", r, socketOperationsownerType))
 	}
 }
 
@@ -79,7 +79,7 @@ func (r *socketOpsCommonRefs) IncRef() {
 // other TryIncRef calls from genuine references held.
 //
 //go:nosplit
-func (r *socketOpsCommonRefs) TryIncRef() bool {
+func (r *socketOperationsRefs) TryIncRef() bool {
 	const speculativeRef = 1 << 32
 	v := atomic.AddInt64(&r.refCount, speculativeRef)
 	if int32(v) < 0 {
@@ -104,10 +104,10 @@ func (r *socketOpsCommonRefs) TryIncRef() bool {
 //	A: TryIncRef [transform speculative to real]
 //
 //go:nosplit
-func (r *socketOpsCommonRefs) DecRef(destroy func()) {
+func (r *socketOperationsRefs) DecRef(destroy func()) {
 	switch v := atomic.AddInt64(&r.refCount, -1); {
 	case v < -1:
-		panic(fmt.Sprintf("Decrementing non-positive ref count %p, owned by %T", r, socketOpsCommonownerType))
+		panic(fmt.Sprintf("Decrementing non-positive ref count %p, owned by %T", r, socketOperationsownerType))
 
 	case v == -1:
 
diff --git a/pkg/sentry/socket/unix/socket_vfs2_refs.go b/pkg/sentry/socket/unix/socket_vfs2_refs.go
new file mode 100644
index 000000000..dc55f2947
--- /dev/null
+++ b/pkg/sentry/socket/unix/socket_vfs2_refs.go
@@ -0,0 +1,118 @@
+package unix
+
+import (
+	"fmt"
+	"runtime"
+	"sync/atomic"
+
+	"gvisor.dev/gvisor/pkg/log"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+)
+
+// ownerType is used to customize logging. Note that we use a pointer to T so
+// that we do not copy the entire object when passed as a format parameter.
+var socketVFS2ownerType *SocketVFS2
+
+// Refs implements refs.RefCounter. It keeps a reference count using atomic
+// operations and calls the destructor when the count reaches zero.
+//
+// Note that the number of references is actually refCount + 1 so that a default
+// zero-value Refs object contains one reference.
+//
+// TODO(gvisor.dev/issue/1486): Store stack traces when leak check is enabled in
+// a map with 16-bit hashes, and store the hash in the top 16 bits of refCount.
+// This will allow us to add stack trace information to the leak messages
+// without growing the size of Refs.
+//
+// +stateify savable
+type socketVFS2Refs struct {
+	// refCount is composed of two fields:
+	//
+	//	[32-bit speculative references]:[32-bit real references]
+	//
+	// Speculative references are used for TryIncRef, to avoid a CompareAndSwap
+	// loop. See IncRef, DecRef and TryIncRef for details of how these fields are
+	// used.
+	refCount int64
+}
+
+func (r *socketVFS2Refs) finalize() {
+	var note string
+	switch refs_vfs1.GetLeakMode() {
+	case refs_vfs1.NoLeakChecking:
+		return
+	case refs_vfs1.UninitializedLeakChecking:
+		note = "(Leak checker uninitialized): "
+	}
+	if n := r.ReadRefs(); n != 0 {
+		log.Warningf("%sRefs %p owned by %T garbage collected with ref count of %d (want 0)", note, r, socketVFS2ownerType, n)
+	}
+}
+
+// EnableLeakCheck checks for reference leaks when Refs gets garbage collected.
+func (r *socketVFS2Refs) EnableLeakCheck() {
+	if refs_vfs1.GetLeakMode() != refs_vfs1.NoLeakChecking {
+		runtime.SetFinalizer(r, (*socketVFS2Refs).finalize)
+	}
+}
+
+// ReadRefs returns the current number of references. The returned count is
+// inherently racy and is unsafe to use without external synchronization.
+func (r *socketVFS2Refs) ReadRefs() int64 {
+
+	return atomic.LoadInt64(&r.refCount) + 1
+}
+
+// IncRef implements refs.RefCounter.IncRef.
+//
+//go:nosplit
+func (r *socketVFS2Refs) IncRef() {
+	if v := atomic.AddInt64(&r.refCount, 1); v <= 0 {
+		panic(fmt.Sprintf("Incrementing non-positive ref count %p owned by %T", r, socketVFS2ownerType))
+	}
+}
+
+// TryIncRef implements refs.RefCounter.TryIncRef.
+//
+// To do this safely without a loop, a speculative reference is first acquired
+// on the object. This allows multiple concurrent TryIncRef calls to distinguish
+// other TryIncRef calls from genuine references held.
+//
+//go:nosplit
+func (r *socketVFS2Refs) TryIncRef() bool {
+	const speculativeRef = 1 << 32
+	v := atomic.AddInt64(&r.refCount, speculativeRef)
+	if int32(v) < 0 {
+
+		atomic.AddInt64(&r.refCount, -speculativeRef)
+		return false
+	}
+
+	atomic.AddInt64(&r.refCount, -speculativeRef+1)
+	return true
+}
+
+// DecRef implements refs.RefCounter.DecRef.
+//
+// Note that speculative references are counted here. Since they were added
+// prior to real references reaching zero, they will successfully convert to
+// real references. In other words, we see speculative references only in the
+// following case:
+//
+//	A: TryIncRef [speculative increase => sees non-negative references]
+//	B: DecRef [real decrease]
+//	A: TryIncRef [transform speculative to real]
+//
+//go:nosplit
+func (r *socketVFS2Refs) DecRef(destroy func()) {
+	switch v := atomic.AddInt64(&r.refCount, -1); {
+	case v < -1:
+		panic(fmt.Sprintf("Decrementing non-positive ref count %p, owned by %T", r, socketVFS2ownerType))
+
+	case v == -1:
+
+		if destroy != nil {
+			destroy()
+		}
+	}
+}
diff --git a/pkg/sentry/socket/unix/unix.go b/pkg/sentry/socket/unix/unix.go
index 917055cea..f80011ce4 100644
--- a/pkg/sentry/socket/unix/unix.go
+++ b/pkg/sentry/socket/unix/unix.go
@@ -55,6 +55,7 @@ type SocketOperations struct {
 	fsutil.FileNoopFlush            `state:"nosave"`
 	fsutil.FileUseInodeUnstableAttr `state:"nosave"`
 
+	socketOperationsRefs
 	socketOpsCommon
 }
 
@@ -84,11 +85,27 @@ func NewWithDirent(ctx context.Context, d *fs.Dirent, ep transport.Endpoint, sty
 	return fs.NewFile(ctx, d, flags, &s)
 }
 
+// DecRef implements RefCounter.DecRef.
+func (s *SocketOperations) DecRef(ctx context.Context) {
+	s.socketOperationsRefs.DecRef(func() {
+		s.ep.Close(ctx)
+		if s.abstractNamespace != nil {
+			s.abstractNamespace.Remove(s.abstractName, s)
+		}
+	})
+}
+
+// Release implemements fs.FileOperations.Release.
+func (s *SocketOperations) Release(ctx context.Context) {
+	// Release only decrements a reference on s because s may be referenced in
+	// the abstract socket namespace.
+	s.DecRef(ctx)
+}
+
 // socketOpsCommon contains the socket operations common to VFS1 and VFS2.
 //
 // +stateify savable
 type socketOpsCommon struct {
-	socketOpsCommonRefs
 	socket.SendReceiveTimeout
 
 	ep    transport.Endpoint
@@ -101,23 +118,6 @@ type socketOpsCommon struct {
 	abstractNamespace *kernel.AbstractSocketNamespace
 }
 
-// DecRef implements RefCounter.DecRef.
-func (s *socketOpsCommon) DecRef(ctx context.Context) {
-	s.socketOpsCommonRefs.DecRef(func() {
-		s.ep.Close(ctx)
-		if s.abstractNamespace != nil {
-			s.abstractNamespace.Remove(s.abstractName, s)
-		}
-	})
-}
-
-// Release implemements fs.FileOperations.Release.
-func (s *socketOpsCommon) Release(ctx context.Context) {
-	// Release only decrements a reference on s because s may be referenced in
-	// the abstract socket namespace.
-	s.DecRef(ctx)
-}
-
 func (s *socketOpsCommon) isPacket() bool {
 	switch s.stype {
 	case linux.SOCK_DGRAM, linux.SOCK_SEQPACKET:
diff --git a/pkg/sentry/socket/unix/unix_state_autogen.go b/pkg/sentry/socket/unix/unix_state_autogen.go
index 89d78a9ad..51fd66b78 100644
--- a/pkg/sentry/socket/unix/unix_state_autogen.go
+++ b/pkg/sentry/socket/unix/unix_state_autogen.go
@@ -6,26 +6,49 @@ import (
 	"gvisor.dev/gvisor/pkg/state"
 )
 
-func (x *socketOpsCommonRefs) StateTypeName() string {
-	return "pkg/sentry/socket/unix.socketOpsCommonRefs"
+func (x *socketOperationsRefs) StateTypeName() string {
+	return "pkg/sentry/socket/unix.socketOperationsRefs"
 }
 
-func (x *socketOpsCommonRefs) StateFields() []string {
+func (x *socketOperationsRefs) StateFields() []string {
 	return []string{
 		"refCount",
 	}
 }
 
-func (x *socketOpsCommonRefs) beforeSave() {}
+func (x *socketOperationsRefs) beforeSave() {}
 
-func (x *socketOpsCommonRefs) StateSave(m state.Sink) {
+func (x *socketOperationsRefs) StateSave(m state.Sink) {
 	x.beforeSave()
 	m.Save(0, &x.refCount)
 }
 
-func (x *socketOpsCommonRefs) afterLoad() {}
+func (x *socketOperationsRefs) afterLoad() {}
 
-func (x *socketOpsCommonRefs) StateLoad(m state.Source) {
+func (x *socketOperationsRefs) StateLoad(m state.Source) {
+	m.Load(0, &x.refCount)
+}
+
+func (x *socketVFS2Refs) StateTypeName() string {
+	return "pkg/sentry/socket/unix.socketVFS2Refs"
+}
+
+func (x *socketVFS2Refs) StateFields() []string {
+	return []string{
+		"refCount",
+	}
+}
+
+func (x *socketVFS2Refs) beforeSave() {}
+
+func (x *socketVFS2Refs) StateSave(m state.Sink) {
+	x.beforeSave()
+	m.Save(0, &x.refCount)
+}
+
+func (x *socketVFS2Refs) afterLoad() {}
+
+func (x *socketVFS2Refs) StateLoad(m state.Source) {
 	m.Load(0, &x.refCount)
 }
 
@@ -35,6 +58,7 @@ func (x *SocketOperations) StateTypeName() string {
 
 func (x *SocketOperations) StateFields() []string {
 	return []string{
+		"socketOperationsRefs",
 		"socketOpsCommon",
 	}
 }
@@ -43,13 +67,15 @@ func (x *SocketOperations) beforeSave() {}
 
 func (x *SocketOperations) StateSave(m state.Sink) {
 	x.beforeSave()
-	m.Save(0, &x.socketOpsCommon)
+	m.Save(0, &x.socketOperationsRefs)
+	m.Save(1, &x.socketOpsCommon)
 }
 
 func (x *SocketOperations) afterLoad() {}
 
 func (x *SocketOperations) StateLoad(m state.Source) {
-	m.Load(0, &x.socketOpsCommon)
+	m.Load(0, &x.socketOperationsRefs)
+	m.Load(1, &x.socketOpsCommon)
 }
 
 func (x *socketOpsCommon) StateTypeName() string {
@@ -58,7 +84,6 @@ func (x *socketOpsCommon) StateTypeName() string {
 
 func (x *socketOpsCommon) StateFields() []string {
 	return []string{
-		"socketOpsCommonRefs",
 		"SendReceiveTimeout",
 		"ep",
 		"stype",
@@ -71,23 +96,21 @@ func (x *socketOpsCommon) beforeSave() {}
 
 func (x *socketOpsCommon) StateSave(m state.Sink) {
 	x.beforeSave()
-	m.Save(0, &x.socketOpsCommonRefs)
-	m.Save(1, &x.SendReceiveTimeout)
-	m.Save(2, &x.ep)
-	m.Save(3, &x.stype)
-	m.Save(4, &x.abstractName)
-	m.Save(5, &x.abstractNamespace)
+	m.Save(0, &x.SendReceiveTimeout)
+	m.Save(1, &x.ep)
+	m.Save(2, &x.stype)
+	m.Save(3, &x.abstractName)
+	m.Save(4, &x.abstractNamespace)
 }
 
 func (x *socketOpsCommon) afterLoad() {}
 
 func (x *socketOpsCommon) StateLoad(m state.Source) {
-	m.Load(0, &x.socketOpsCommonRefs)
-	m.Load(1, &x.SendReceiveTimeout)
-	m.Load(2, &x.ep)
-	m.Load(3, &x.stype)
-	m.Load(4, &x.abstractName)
-	m.Load(5, &x.abstractNamespace)
+	m.Load(0, &x.SendReceiveTimeout)
+	m.Load(1, &x.ep)
+	m.Load(2, &x.stype)
+	m.Load(3, &x.abstractName)
+	m.Load(4, &x.abstractNamespace)
 }
 
 func (x *SocketVFS2) StateTypeName() string {
@@ -100,6 +123,7 @@ func (x *SocketVFS2) StateFields() []string {
 		"FileDescriptionDefaultImpl",
 		"DentryMetadataFileDescriptionImpl",
 		"LockFD",
+		"socketVFS2Refs",
 		"socketOpsCommon",
 	}
 }
@@ -112,7 +136,8 @@ func (x *SocketVFS2) StateSave(m state.Sink) {
 	m.Save(1, &x.FileDescriptionDefaultImpl)
 	m.Save(2, &x.DentryMetadataFileDescriptionImpl)
 	m.Save(3, &x.LockFD)
-	m.Save(4, &x.socketOpsCommon)
+	m.Save(4, &x.socketVFS2Refs)
+	m.Save(5, &x.socketOpsCommon)
 }
 
 func (x *SocketVFS2) afterLoad() {}
@@ -122,11 +147,13 @@ func (x *SocketVFS2) StateLoad(m state.Source) {
 	m.Load(1, &x.FileDescriptionDefaultImpl)
 	m.Load(2, &x.DentryMetadataFileDescriptionImpl)
 	m.Load(3, &x.LockFD)
-	m.Load(4, &x.socketOpsCommon)
+	m.Load(4, &x.socketVFS2Refs)
+	m.Load(5, &x.socketOpsCommon)
 }
 
 func init() {
-	state.Register((*socketOpsCommonRefs)(nil))
+	state.Register((*socketOperationsRefs)(nil))
+	state.Register((*socketVFS2Refs)(nil))
 	state.Register((*SocketOperations)(nil))
 	state.Register((*socketOpsCommon)(nil))
 	state.Register((*SocketVFS2)(nil))
diff --git a/pkg/sentry/socket/unix/unix_vfs2.go b/pkg/sentry/socket/unix/unix_vfs2.go
index 8b1abd922..3345124cc 100644
--- a/pkg/sentry/socket/unix/unix_vfs2.go
+++ b/pkg/sentry/socket/unix/unix_vfs2.go
@@ -45,6 +45,7 @@ type SocketVFS2 struct {
 	vfs.DentryMetadataFileDescriptionImpl
 	vfs.LockFD
 
+	socketVFS2Refs
 	socketOpsCommon
 }
 
@@ -91,6 +92,25 @@ func NewFileDescription(ep transport.Endpoint, stype linux.SockType, flags uint3
 	return vfsfd, nil
 }
 
+// DecRef implements RefCounter.DecRef.
+func (s *SocketVFS2) DecRef(ctx context.Context) {
+	s.socketVFS2Refs.DecRef(func() {
+		t := kernel.TaskFromContext(ctx)
+		t.Kernel().DeleteSocketVFS2(&s.vfsfd)
+		s.ep.Close(ctx)
+		if s.abstractNamespace != nil {
+			s.abstractNamespace.Remove(s.abstractName, s)
+		}
+	})
+}
+
+// Release implements vfs.FileDescriptionImpl.Release.
+func (s *SocketVFS2) Release(ctx context.Context) {
+	// Release only decrements a reference on s because s may be referenced in
+	// the abstract socket namespace.
+	s.DecRef(ctx)
+}
+
 // GetSockOpt implements the linux syscall getsockopt(2) for sockets backed by
 // a transport.Endpoint.
 func (s *SocketVFS2) GetSockOpt(t *kernel.Task, level, name int, outPtr usermem.Addr, outLen int) (marshal.Marshallable, *syserr.Error) {