Merge release-20210518.0-38-g4f2439fb0 (automated)

21 files changed, 214 insertions, 104 deletions

diff --git a/pkg/tcpip/faketime/faketime.go b/pkg/tcpip/faketime/faketime.go
index c4dbe8440..9f8f51647 100644
--- a/pkg/tcpip/faketime/faketime.go
+++ b/pkg/tcpip/faketime/faketime.go
@@ -29,14 +29,14 @@ type NullClock struct{}
 
 var _ tcpip.Clock = (*NullClock)(nil)
 
-// NowNanoseconds implements tcpip.Clock.NowNanoseconds.
-func (*NullClock) NowNanoseconds() int64 {
-	return 0
+// Now implements tcpip.Clock.Now.
+func (*NullClock) Now() time.Time {
+	return time.Time{}
 }
 
 // NowMonotonic implements tcpip.Clock.NowMonotonic.
-func (*NullClock) NowMonotonic() int64 {
-	return 0
+func (*NullClock) NowMonotonic() tcpip.MonotonicTime {
+	return tcpip.MonotonicTime{}
 }
 
 // AfterFunc implements tcpip.Clock.AfterFunc.
@@ -118,16 +118,17 @@ func NewManualClock() *ManualClock {
 
 var _ tcpip.Clock = (*ManualClock)(nil)
 
-// NowNanoseconds implements tcpip.Clock.NowNanoseconds.
-func (mc *ManualClock) NowNanoseconds() int64 {
+// Now implements tcpip.Clock.Now.
+func (mc *ManualClock) Now() time.Time {
 	mc.mu.RLock()
 	defer mc.mu.RUnlock()
-	return mc.mu.now.UnixNano()
+	return mc.mu.now
 }
 
 // NowMonotonic implements tcpip.Clock.NowMonotonic.
-func (mc *ManualClock) NowMonotonic() int64 {
-	return mc.NowNanoseconds()
+func (mc *ManualClock) NowMonotonic() tcpip.MonotonicTime {
+	var mt tcpip.MonotonicTime
+	return mt.Add(mc.Now().Sub(time.Unix(0, 0)))
 }
 
 // AfterFunc implements tcpip.Clock.AfterFunc.
diff --git a/pkg/tcpip/header/ipv4.go b/pkg/tcpip/header/ipv4.go
index 2be21ec75..6a8db84d6 100644
--- a/pkg/tcpip/header/ipv4.go
+++ b/pkg/tcpip/header/ipv4.go
@@ -17,6 +17,7 @@ package header
 import (
 	"encoding/binary"
 	"fmt"
+	"time"
 
 	"gvisor.dev/gvisor/pkg/tcpip"
 )
@@ -813,9 +814,12 @@ const (
 
 // ipv4TimestampTime provides the current time as specified in RFC 791.
 func ipv4TimestampTime(clock tcpip.Clock) uint32 {
-	const millisecondsPerDay = 24 * 3600 * 1000
-	const nanoPerMilli = 1000000
-	return uint32((clock.NowNanoseconds() / nanoPerMilli) % millisecondsPerDay)
+	// Per RFC 791 page 21:
+	//   The Timestamp is a right-justified, 32-bit timestamp in
+	//   milliseconds since midnight UT.
+	now := clock.Now().UTC()
+	midnight := now.Truncate(24 * time.Hour)
+	return uint32(now.Sub(midnight).Milliseconds())
 }
 
 // IP Timestamp option fields.
diff --git a/pkg/tcpip/network/internal/fragmentation/fragmentation.go b/pkg/tcpip/network/internal/fragmentation/fragmentation.go
index 5168f5361..1ba4d0d36 100644
--- a/pkg/tcpip/network/internal/fragmentation/fragmentation.go
+++ b/pkg/tcpip/network/internal/fragmentation/fragmentation.go
@@ -251,7 +251,7 @@ func (f *Fragmentation) releaseReassemblersLocked() {
 			// The list is empty.
 			break
 		}
-		elapsed := time.Duration(now-r.creationTime) * time.Nanosecond
+		elapsed := now.Sub(r.createdAt)
 		if f.timeout > elapsed {
 			// If the oldest reassembler has not expired, schedule the release
 			// job so that this function is called back when it has expired.
diff --git a/pkg/tcpip/network/internal/fragmentation/reassembler.go b/pkg/tcpip/network/internal/fragmentation/reassembler.go
index 56b76a284..5b7e4b361 100644
--- a/pkg/tcpip/network/internal/fragmentation/reassembler.go
+++ b/pkg/tcpip/network/internal/fragmentation/reassembler.go
@@ -35,21 +35,21 @@ type hole struct {
 
 type reassembler struct {
 	reassemblerEntry
-	id           FragmentID
-	memSize      int
-	proto        uint8
-	mu           sync.Mutex
-	holes        []hole
-	filled       int
-	done         bool
-	creationTime int64
-	pkt          *stack.PacketBuffer
+	id        FragmentID
+	memSize   int
+	proto     uint8
+	mu        sync.Mutex
+	holes     []hole
+	filled    int
+	done      bool
+	createdAt tcpip.MonotonicTime
+	pkt       *stack.PacketBuffer
 }
 
 func newReassembler(id FragmentID, clock tcpip.Clock) *reassembler {
 	r := &reassembler{
-		id:           id,
-		creationTime: clock.NowMonotonic(),
+		id:        id,
+		createdAt: clock.NowMonotonic(),
 	}
 	r.holes = append(r.holes, hole{
 		first:  0,
diff --git a/pkg/tcpip/network/internal/ip/generic_multicast_protocol.go b/pkg/tcpip/network/internal/ip/generic_multicast_protocol.go
index d22974b12..671dfbf32 100644
--- a/pkg/tcpip/network/internal/ip/generic_multicast_protocol.go
+++ b/pkg/tcpip/network/internal/ip/generic_multicast_protocol.go
@@ -611,7 +611,7 @@ func (g *GenericMulticastProtocolState) setDelayTimerForAddressRLocked(groupAddr
 	//   If a timer for any address is already running, it is reset to the new
 	//   random value only if the requested Maximum Response Delay is less than
 	//   the remaining value of the running timer.
-	now := time.Unix(0 /* seconds */, g.opts.Clock.NowNanoseconds())
+	now := g.opts.Clock.Now()
 	if info.state == delayingMember {
 		if info.delayedReportJobFiresAt.IsZero() {
 			panic(fmt.Sprintf("delayed report unscheduled while in the delaying member state; group = %s", groupAddress))
diff --git a/pkg/tcpip/stack/neighbor_entry.go b/pkg/tcpip/stack/neighbor_entry.go
index 463d017fc..ab247db2e 100644
--- a/pkg/tcpip/stack/neighbor_entry.go
+++ b/pkg/tcpip/stack/neighbor_entry.go
@@ -31,10 +31,10 @@ const (
 
 // NeighborEntry describes a neighboring device in the local network.
 type NeighborEntry struct {
-	Addr           tcpip.Address
-	LinkAddr       tcpip.LinkAddress
-	State          NeighborState
-	UpdatedAtNanos int64
+	Addr      tcpip.Address
+	LinkAddr  tcpip.LinkAddress
+	State     NeighborState
+	UpdatedAt time.Time
 }
 
 // NeighborState defines the state of a NeighborEntry within the Neighbor
@@ -138,10 +138,10 @@ func newNeighborEntry(cache *neighborCache, remoteAddr tcpip.Address, nudState *
 // calling `setStateLocked`.
 func newStaticNeighborEntry(cache *neighborCache, addr tcpip.Address, linkAddr tcpip.LinkAddress, state *NUDState) *neighborEntry {
 	entry := NeighborEntry{
-		Addr:           addr,
-		LinkAddr:       linkAddr,
-		State:          Static,
-		UpdatedAtNanos: cache.nic.stack.clock.NowNanoseconds(),
+		Addr:      addr,
+		LinkAddr:  linkAddr,
+		State:     Static,
+		UpdatedAt: cache.nic.stack.clock.Now(),
 	}
 	n := &neighborEntry{
 		cache:    cache,
@@ -224,7 +224,7 @@ func (e *neighborEntry) cancelTimerLocked() {
 //
 // Precondition: e.mu MUST be locked.
 func (e *neighborEntry) removeLocked() {
-	e.mu.neigh.UpdatedAtNanos = e.cache.nic.stack.clock.NowNanoseconds()
+	e.mu.neigh.UpdatedAt = e.cache.nic.stack.clock.Now()
 	e.dispatchRemoveEventLocked()
 	e.cancelTimerLocked()
 	// TODO(https://gvisor.dev/issues/5583): test the case where this function is
@@ -246,7 +246,7 @@ func (e *neighborEntry) setStateLocked(next NeighborState) {
 
 	prev := e.mu.neigh.State
 	e.mu.neigh.State = next
-	e.mu.neigh.UpdatedAtNanos = e.cache.nic.stack.clock.NowNanoseconds()
+	e.mu.neigh.UpdatedAt = e.cache.nic.stack.clock.Now()
 	config := e.nudState.Config()
 
 	switch next {
@@ -354,7 +354,7 @@ func (e *neighborEntry) handlePacketQueuedLocked(localAddr tcpip.Address) {
 	case Unknown, Unreachable:
 		prev := e.mu.neigh.State
 		e.mu.neigh.State = Incomplete
-		e.mu.neigh.UpdatedAtNanos = e.cache.nic.stack.clock.NowNanoseconds()
+		e.mu.neigh.UpdatedAt = e.cache.nic.stack.clock.Now()
 
 		switch prev {
 		case Unknown:
diff --git a/pkg/tcpip/stdclock.go b/pkg/tcpip/stdclock.go
index 7ce43a68e..371da2f40 100644
--- a/pkg/tcpip/stdclock.go
+++ b/pkg/tcpip/stdclock.go
@@ -60,11 +60,11 @@ type stdClock struct {
 	// monotonicOffset is assigned maxMonotonic after restore so that the
 	// monotonic time will continue from where it "left off" before saving as part
 	// of S/R.
-	monotonicOffset int64 `state:"nosave"`
+	monotonicOffset MonotonicTime `state:"nosave"`
 
 	// monotonicMU protects maxMonotonic.
 	monotonicMU  sync.Mutex `state:"nosave"`
-	maxMonotonic int64
+	maxMonotonic MonotonicTime
 }
 
 // NewStdClock returns an instance of a clock that uses the time package.
@@ -76,25 +76,25 @@ func NewStdClock() Clock {
 
 var _ Clock = (*stdClock)(nil)
 
-// NowNanoseconds implements Clock.NowNanoseconds.
-func (*stdClock) NowNanoseconds() int64 {
-	return time.Now().UnixNano()
+// Now implements Clock.Now.
+func (*stdClock) Now() time.Time {
+	return time.Now()
 }
 
 // NowMonotonic implements Clock.NowMonotonic.
-func (s *stdClock) NowMonotonic() int64 {
+func (s *stdClock) NowMonotonic() MonotonicTime {
 	sinceBase := time.Since(s.baseTime)
 	if sinceBase < 0 {
 		panic(fmt.Sprintf("got negative duration = %s since base time = %s", sinceBase, s.baseTime))
 	}
 
-	monotonicValue := sinceBase.Nanoseconds() + s.monotonicOffset
+	monotonicValue := s.monotonicOffset.Add(sinceBase)
 
 	s.monotonicMU.Lock()
 	defer s.monotonicMU.Unlock()
 
 	// Monotonic time values must never decrease.
-	if monotonicValue > s.maxMonotonic {
+	if s.maxMonotonic.Before(monotonicValue) {
 		s.maxMonotonic = monotonicValue
 	}
 
diff --git a/pkg/tcpip/tcpip.go b/pkg/tcpip/tcpip.go
index 34f820053..ca98da847 100644
--- a/pkg/tcpip/tcpip.go
+++ b/pkg/tcpip/tcpip.go
@@ -64,17 +64,42 @@ func (e *ErrSaveRejection) Error() string {
 	return "save rejected due to unsupported networking state: " + e.Err.Error()
 }
 
+// MonotonicTime is a monotonic clock reading.
+//
+// +stateify savable
+type MonotonicTime struct {
+	nanoseconds int64
+}
+
+// Before reports whether the monotonic clock reading mt is before u.
+func (mt MonotonicTime) Before(u MonotonicTime) bool {
+	return mt.nanoseconds < u.nanoseconds
+}
+
+// Add returns the monotonic clock reading mt+d.
+func (mt MonotonicTime) Add(d time.Duration) MonotonicTime {
+	return MonotonicTime{
+		nanoseconds: time.Unix(0, mt.nanoseconds).Add(d).Sub(time.Unix(0, 0)).Nanoseconds(),
+	}
+}
+
+// Sub returns the duration mt-u. If the result exceeds the maximum (or minimum)
+// value that can be stored in a Duration, the maximum (or minimum) duration
+// will be returned. To compute t-d for a duration d, use t.Add(-d).
+func (mt MonotonicTime) Sub(u MonotonicTime) time.Duration {
+	return time.Unix(0, mt.nanoseconds).Sub(time.Unix(0, u.nanoseconds))
+}
+
 // A Clock provides the current time and schedules work for execution.
 //
 // Times returned by a Clock should always be used for application-visible
 // time. Only monotonic times should be used for netstack internal timekeeping.
 type Clock interface {
-	// NowNanoseconds returns the current real time as a number of
-	// nanoseconds since the Unix epoch.
-	NowNanoseconds() int64
+	// Now returns the current local time.
+	Now() time.Time
 
-	// NowMonotonic returns a monotonic time value at nanosecond resolution.
-	NowMonotonic() int64
+	// NowMonotonic returns the current monotonic clock reading.
+	NowMonotonic() MonotonicTime
 
 	// AfterFunc waits for the duration to elapse and then calls f in its own
 	// goroutine. It returns a Timer that can be used to cancel the call using
diff --git a/pkg/tcpip/tcpip_state_autogen.go b/pkg/tcpip/tcpip_state_autogen.go
index 812a300ca..9c34de9ef 100644
--- a/pkg/tcpip/tcpip_state_autogen.go
+++ b/pkg/tcpip/tcpip_state_autogen.go
@@ -1064,6 +1064,31 @@ func (s *stdClock) StateLoad(stateSourceObject state.Source) {
 	stateSourceObject.AfterLoad(s.afterLoad)
 }
 
+func (mt *MonotonicTime) StateTypeName() string {
+	return "pkg/tcpip.MonotonicTime"
+}
+
+func (mt *MonotonicTime) StateFields() []string {
+	return []string{
+		"nanoseconds",
+	}
+}
+
+func (mt *MonotonicTime) beforeSave() {}
+
+// +checklocksignore
+func (mt *MonotonicTime) StateSave(stateSinkObject state.Sink) {
+	mt.beforeSave()
+	stateSinkObject.Save(0, &mt.nanoseconds)
+}
+
+func (mt *MonotonicTime) afterLoad() {}
+
+// +checklocksignore
+func (mt *MonotonicTime) StateLoad(stateSourceObject state.Source) {
+	stateSourceObject.Load(0, &mt.nanoseconds)
+}
+
 func (f *FullAddress) StateTypeName() string {
 	return "pkg/tcpip.FullAddress"
 }
@@ -1289,6 +1314,7 @@ func init() {
 	state.Register((*LocalSockError)(nil))
 	state.Register((*SockError)(nil))
 	state.Register((*stdClock)(nil))
+	state.Register((*MonotonicTime)(nil))
 	state.Register((*FullAddress)(nil))
 	state.Register((*ControlMessages)(nil))
 	state.Register((*LinkPacketInfo)(nil))
diff --git a/pkg/tcpip/transport/icmp/endpoint.go b/pkg/tcpip/transport/icmp/endpoint.go
index 517903ae7..d92b123c4 100644
--- a/pkg/tcpip/transport/icmp/endpoint.go
+++ b/pkg/tcpip/transport/icmp/endpoint.go
@@ -16,6 +16,7 @@ package icmp
 
 import (
 	"io"
+	"time"
 
 	"gvisor.dev/gvisor/pkg/sync"
 	"gvisor.dev/gvisor/pkg/tcpip"
@@ -33,7 +34,7 @@ type icmpPacket struct {
 	icmpPacketEntry
 	senderAddress tcpip.FullAddress
 	data          buffer.VectorisedView `state:".(buffer.VectorisedView)"`
-	timestamp     int64
+	receivedAt    time.Time             `state:".(int64)"`
 }
 
 type endpointState int
@@ -193,7 +194,7 @@ func (e *endpoint) Read(dst io.Writer, opts tcpip.ReadOptions) (tcpip.ReadResult
 		Total: p.data.Size(),
 		ControlMessages: tcpip.ControlMessages{
 			HasTimestamp: true,
-			Timestamp:    p.timestamp,
+			Timestamp:    p.receivedAt.UnixNano(),
 		},
 	}
 	if opts.NeedRemoteAddr {
@@ -800,7 +801,7 @@ func (e *endpoint) HandlePacket(id stack.TransportEndpointID, pkt *stack.PacketB
 	e.rcvList.PushBack(packet)
 	e.rcvBufSize += packet.data.Size()
 
-	packet.timestamp = e.stack.Clock().NowNanoseconds()
+	packet.receivedAt = e.stack.Clock().Now()
 
 	e.rcvMu.Unlock()
 	e.stats.PacketsReceived.Increment()
diff --git a/pkg/tcpip/transport/icmp/endpoint_state.go b/pkg/tcpip/transport/icmp/endpoint_state.go
index 28a56a2d5..b8b839e4a 100644
--- a/pkg/tcpip/transport/icmp/endpoint_state.go
+++ b/pkg/tcpip/transport/icmp/endpoint_state.go
@@ -15,11 +15,23 @@
 package icmp
 
 import (
+	"time"
+
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
 )
 
+// saveReceivedAt is invoked by stateify.
+func (p *icmpPacket) saveReceivedAt() int64 {
+	return p.receivedAt.UnixNano()
+}
+
+// loadReceivedAt is invoked by stateify.
+func (p *icmpPacket) loadReceivedAt(nsec int64) {
+	p.receivedAt = time.Unix(0, nsec)
+}
+
 // saveData saves icmpPacket.data field.
 func (p *icmpPacket) saveData() buffer.VectorisedView {
 	// We cannot save p.data directly as p.data.views may alias to p.views,
diff --git a/pkg/tcpip/transport/icmp/icmp_state_autogen.go b/pkg/tcpip/transport/icmp/icmp_state_autogen.go
index 98c1b06a3..acfc8ff5f 100644
--- a/pkg/tcpip/transport/icmp/icmp_state_autogen.go
+++ b/pkg/tcpip/transport/icmp/icmp_state_autogen.go
@@ -16,7 +16,7 @@ func (p *icmpPacket) StateFields() []string {
 		"icmpPacketEntry",
 		"senderAddress",
 		"data",
-		"timestamp",
+		"receivedAt",
 	}
 }
 
@@ -27,9 +27,10 @@ func (p *icmpPacket) StateSave(stateSinkObject state.Sink) {
 	p.beforeSave()
 	var dataValue buffer.VectorisedView = p.saveData()
 	stateSinkObject.SaveValue(2, dataValue)
+	var receivedAtValue int64 = p.saveReceivedAt()
+	stateSinkObject.SaveValue(3, receivedAtValue)
 	stateSinkObject.Save(0, &p.icmpPacketEntry)
 	stateSinkObject.Save(1, &p.senderAddress)
-	stateSinkObject.Save(3, &p.timestamp)
 }
 
 func (p *icmpPacket) afterLoad() {}
@@ -38,8 +39,8 @@ func (p *icmpPacket) afterLoad() {}
 func (p *icmpPacket) StateLoad(stateSourceObject state.Source) {
 	stateSourceObject.Load(0, &p.icmpPacketEntry)
 	stateSourceObject.Load(1, &p.senderAddress)
-	stateSourceObject.Load(3, &p.timestamp)
 	stateSourceObject.LoadValue(2, new(buffer.VectorisedView), func(y interface{}) { p.loadData(y.(buffer.VectorisedView)) })
+	stateSourceObject.LoadValue(3, new(int64), func(y interface{}) { p.loadReceivedAt(y.(int64)) })
 }
 
 func (e *endpoint) StateTypeName() string {
diff --git a/pkg/tcpip/transport/packet/endpoint.go b/pkg/tcpip/transport/packet/endpoint.go
index fa703a0ed..cd8c99d41 100644
--- a/pkg/tcpip/transport/packet/endpoint.go
+++ b/pkg/tcpip/transport/packet/endpoint.go
@@ -27,6 +27,7 @@ package packet
 import (
 	"fmt"
 	"io"
+	"time"
 
 	"gvisor.dev/gvisor/pkg/sync"
 	"gvisor.dev/gvisor/pkg/tcpip"
@@ -41,9 +42,8 @@ type packet struct {
 	packetEntry
 	// data holds the actual packet data, including any headers and
 	// payload.
-	data buffer.VectorisedView `state:".(buffer.VectorisedView)"`
-	// timestampNS is the unix time at which the packet was received.
-	timestampNS int64
+	data       buffer.VectorisedView `state:".(buffer.VectorisedView)"`
+	receivedAt time.Time             `state:".(int64)"`
 	// senderAddr is the network address of the sender.
 	senderAddr tcpip.FullAddress
 	// packetInfo holds additional information like the protocol
@@ -189,7 +189,7 @@ func (ep *endpoint) Read(dst io.Writer, opts tcpip.ReadOptions) (tcpip.ReadResul
 		Total: packet.data.Size(),
 		ControlMessages: tcpip.ControlMessages{
 			HasTimestamp: true,
-			Timestamp:    packet.timestampNS,
+			Timestamp:    packet.receivedAt.UnixNano(),
 		},
 	}
 	if opts.NeedRemoteAddr {
@@ -451,7 +451,7 @@ func (ep *endpoint) HandlePacket(nicID tcpip.NICID, localAddr tcpip.LinkAddress,
 			packet.data = buffer.NewVectorisedView(pkt.Size(), pkt.Views())
 		}
 	}
-	packet.timestampNS = ep.stack.Clock().NowNanoseconds()
+	packet.receivedAt = ep.stack.Clock().Now()
 
 	ep.rcvList.PushBack(&packet)
 	ep.rcvBufSize += packet.data.Size()
diff --git a/pkg/tcpip/transport/packet/endpoint_state.go b/pkg/tcpip/transport/packet/endpoint_state.go
index 5bd860d20..e729921db 100644
--- a/pkg/tcpip/transport/packet/endpoint_state.go
+++ b/pkg/tcpip/transport/packet/endpoint_state.go
@@ -15,11 +15,23 @@
 package packet
 
 import (
+	"time"
+
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
 )
 
+// saveReceivedAt is invoked by stateify.
+func (p *packet) saveReceivedAt() int64 {
+	return p.receivedAt.UnixNano()
+}
+
+// loadReceivedAt is invoked by stateify.
+func (p *packet) loadReceivedAt(nsec int64) {
+	p.receivedAt = time.Unix(0, nsec)
+}
+
 // saveData saves packet.data field.
 func (p *packet) saveData() buffer.VectorisedView {
 	// We cannot save p.data directly as p.data.views may alias to p.views,
diff --git a/pkg/tcpip/transport/packet/packet_state_autogen.go b/pkg/tcpip/transport/packet/packet_state_autogen.go
index b354c87b1..304f67c12 100644
--- a/pkg/tcpip/transport/packet/packet_state_autogen.go
+++ b/pkg/tcpip/transport/packet/packet_state_autogen.go
@@ -15,7 +15,7 @@ func (p *packet) StateFields() []string {
 	return []string{
 		"packetEntry",
 		"data",
-		"timestampNS",
+		"receivedAt",
 		"senderAddr",
 		"packetInfo",
 	}
@@ -28,8 +28,9 @@ func (p *packet) StateSave(stateSinkObject state.Sink) {
 	p.beforeSave()
 	var dataValue buffer.VectorisedView = p.saveData()
 	stateSinkObject.SaveValue(1, dataValue)
+	var receivedAtValue int64 = p.saveReceivedAt()
+	stateSinkObject.SaveValue(2, receivedAtValue)
 	stateSinkObject.Save(0, &p.packetEntry)
-	stateSinkObject.Save(2, &p.timestampNS)
 	stateSinkObject.Save(3, &p.senderAddr)
 	stateSinkObject.Save(4, &p.packetInfo)
 }
@@ -39,10 +40,10 @@ func (p *packet) afterLoad() {}
 // +checklocksignore
 func (p *packet) StateLoad(stateSourceObject state.Source) {
 	stateSourceObject.Load(0, &p.packetEntry)
-	stateSourceObject.Load(2, &p.timestampNS)
 	stateSourceObject.Load(3, &p.senderAddr)
 	stateSourceObject.Load(4, &p.packetInfo)
 	stateSourceObject.LoadValue(1, new(buffer.VectorisedView), func(y interface{}) { p.loadData(y.(buffer.VectorisedView)) })
+	stateSourceObject.LoadValue(2, new(int64), func(y interface{}) { p.loadReceivedAt(y.(int64)) })
 }
 
 func (ep *endpoint) StateTypeName() string {
diff --git a/pkg/tcpip/transport/raw/endpoint.go b/pkg/tcpip/transport/raw/endpoint.go
index 07a585444..1bce2769a 100644
--- a/pkg/tcpip/transport/raw/endpoint.go
+++ b/pkg/tcpip/transport/raw/endpoint.go
@@ -27,6 +27,7 @@ package raw
 
 import (
 	"io"
+	"time"
 
 	"gvisor.dev/gvisor/pkg/sync"
 	"gvisor.dev/gvisor/pkg/tcpip"
@@ -41,9 +42,8 @@ type rawPacket struct {
 	rawPacketEntry
 	// data holds the actual packet data, including any headers and
 	// payload.
-	data buffer.VectorisedView `state:".(buffer.VectorisedView)"`
-	// timestampNS is the unix time at which the packet was received.
-	timestampNS int64
+	data       buffer.VectorisedView `state:".(buffer.VectorisedView)"`
+	receivedAt time.Time             `state:".(int64)"`
 	// senderAddr is the network address of the sender.
 	senderAddr tcpip.FullAddress
 }
@@ -219,7 +219,7 @@ func (e *endpoint) Read(dst io.Writer, opts tcpip.ReadOptions) (tcpip.ReadResult
 		Total: pkt.data.Size(),
 		ControlMessages: tcpip.ControlMessages{
 			HasTimestamp: true,
-			Timestamp:    pkt.timestampNS,
+			Timestamp:    pkt.receivedAt.UnixNano(),
 		},
 	}
 	if opts.NeedRemoteAddr {
@@ -621,7 +621,7 @@ func (e *endpoint) HandlePacket(pkt *stack.PacketBuffer) {
 	}
 	combinedVV.Append(pkt.Data().ExtractVV())
 	packet.data = combinedVV
-	packet.timestampNS = e.stack.Clock().NowNanoseconds()
+	packet.receivedAt = e.stack.Clock().Now()
 
 	e.rcvList.PushBack(packet)
 	e.rcvBufSize += packet.data.Size()
diff --git a/pkg/tcpip/transport/raw/endpoint_state.go b/pkg/tcpip/transport/raw/endpoint_state.go
index 5d6f2709c..39669b445 100644
--- a/pkg/tcpip/transport/raw/endpoint_state.go
+++ b/pkg/tcpip/transport/raw/endpoint_state.go
@@ -15,11 +15,23 @@
 package raw
 
 import (
+	"time"
+
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
 )
 
+// saveReceivedAt is invoked by stateify.
+func (p *rawPacket) saveReceivedAt() int64 {
+	return p.receivedAt.UnixNano()
+}
+
+// loadReceivedAt is invoked by stateify.
+func (p *rawPacket) loadReceivedAt(nsec int64) {
+	p.receivedAt = time.Unix(0, nsec)
+}
+
 // saveData saves rawPacket.data field.
 func (p *rawPacket) saveData() buffer.VectorisedView {
 	// We cannot save p.data directly as p.data.views may alias to p.views,
diff --git a/pkg/tcpip/transport/raw/raw_state_autogen.go b/pkg/tcpip/transport/raw/raw_state_autogen.go
index 2bcd983a2..aaeed9775 100644
--- a/pkg/tcpip/transport/raw/raw_state_autogen.go
+++ b/pkg/tcpip/transport/raw/raw_state_autogen.go
@@ -15,7 +15,7 @@ func (p *rawPacket) StateFields() []string {
 	return []string{
 		"rawPacketEntry",
 		"data",
-		"timestampNS",
+		"receivedAt",
 		"senderAddr",
 	}
 }
@@ -27,8 +27,9 @@ func (p *rawPacket) StateSave(stateSinkObject state.Sink) {
 	p.beforeSave()
 	var dataValue buffer.VectorisedView = p.saveData()
 	stateSinkObject.SaveValue(1, dataValue)
+	var receivedAtValue int64 = p.saveReceivedAt()
+	stateSinkObject.SaveValue(2, receivedAtValue)
 	stateSinkObject.Save(0, &p.rawPacketEntry)
-	stateSinkObject.Save(2, &p.timestampNS)
 	stateSinkObject.Save(3, &p.senderAddr)
 }
 
@@ -37,9 +38,9 @@ func (p *rawPacket) afterLoad() {}
 // +checklocksignore
 func (p *rawPacket) StateLoad(stateSourceObject state.Source) {
 	stateSourceObject.Load(0, &p.rawPacketEntry)
-	stateSourceObject.Load(2, &p.timestampNS)
 	stateSourceObject.Load(3, &p.senderAddr)
 	stateSourceObject.LoadValue(1, new(buffer.VectorisedView), func(y interface{}) { p.loadData(y.(buffer.VectorisedView)) })
+	stateSourceObject.LoadValue(2, new(int64), func(y interface{}) { p.loadReceivedAt(y.(int64)) })
 }
 
 func (e *endpoint) StateTypeName() string {
diff --git a/pkg/tcpip/transport/udp/endpoint.go b/pkg/tcpip/transport/udp/endpoint.go
index 623e069a6..83b589d09 100644
--- a/pkg/tcpip/transport/udp/endpoint.go
+++ b/pkg/tcpip/transport/udp/endpoint.go
@@ -17,6 +17,7 @@ package udp
 import (
 	"io"
 	"sync/atomic"
+	"time"
 
 	"gvisor.dev/gvisor/pkg/sync"
 	"gvisor.dev/gvisor/pkg/tcpip"
@@ -34,7 +35,7 @@ type udpPacket struct {
 	destinationAddress tcpip.FullAddress
 	packetInfo         tcpip.IPPacketInfo
 	data               buffer.VectorisedView `state:".(buffer.VectorisedView)"`
-	timestamp          int64
+	receivedAt         time.Time             `state:".(int64)"`
 	// tos stores either the receiveTOS or receiveTClass value.
 	tos uint8
 }
@@ -321,7 +322,7 @@ func (e *endpoint) Read(dst io.Writer, opts tcpip.ReadOptions) (tcpip.ReadResult
 	// Control Messages
 	cm := tcpip.ControlMessages{
 		HasTimestamp: true,
-		Timestamp:    p.timestamp,
+		Timestamp:    p.receivedAt.UnixNano(),
 	}
 	if e.ops.GetReceiveTOS() {
 		cm.HasTOS = true
@@ -1329,7 +1330,7 @@ func (e *endpoint) HandlePacket(id stack.TransportEndpointID, pkt *stack.PacketB
 	packet.packetInfo.LocalAddr = localAddr
 	packet.packetInfo.DestinationAddr = localAddr
 	packet.packetInfo.NIC = pkt.NICID
-	packet.timestamp = e.stack.Clock().NowNanoseconds()
+	packet.receivedAt = e.stack.Clock().Now()
 
 	e.rcvMu.Unlock()
 
diff --git a/pkg/tcpip/transport/udp/endpoint_state.go b/pkg/tcpip/transport/udp/endpoint_state.go
index 4aba68b21..1f638c3f6 100644
--- a/pkg/tcpip/transport/udp/endpoint_state.go
+++ b/pkg/tcpip/transport/udp/endpoint_state.go
@@ -15,26 +15,38 @@
 package udp
 
 import (
+	"time"
+
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip/header"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
 )
 
+// saveReceivedAt is invoked by stateify.
+func (p *udpPacket) saveReceivedAt() int64 {
+	return p.receivedAt.UnixNano()
+}
+
+// loadReceivedAt is invoked by stateify.
+func (p *udpPacket) loadReceivedAt(nsec int64) {
+	p.receivedAt = time.Unix(0, nsec)
+}
+
 // saveData saves udpPacket.data field.
-func (u *udpPacket) saveData() buffer.VectorisedView {
-	// We cannot save u.data directly as u.data.views may alias to u.views,
+func (p *udpPacket) saveData() buffer.VectorisedView {
+	// We cannot save p.data directly as p.data.views may alias to p.views,
 	// which is not allowed by state framework (in-struct pointer).
-	return u.data.Clone(nil)
+	return p.data.Clone(nil)
 }
 
 // loadData loads udpPacket.data field.
-func (u *udpPacket) loadData(data buffer.VectorisedView) {
-	// NOTE: We cannot do the u.data = data.Clone(u.views[:]) optimization
+func (p *udpPacket) loadData(data buffer.VectorisedView) {
+	// NOTE: We cannot do the p.data = data.Clone(p.views[:]) optimization
 	// here because data.views is not guaranteed to be loaded by now. Plus,
 	// data.views will be allocated anyway so there really is little point
-	// of utilizing u.views for data.views.
-	u.data = data
+	// of utilizing p.views for data.views.
+	p.data = data
 }
 
 // afterLoad is invoked by stateify.
diff --git a/pkg/tcpip/transport/udp/udp_state_autogen.go b/pkg/tcpip/transport/udp/udp_state_autogen.go
index 092daa0b8..6a3da67e2 100644
--- a/pkg/tcpip/transport/udp/udp_state_autogen.go
+++ b/pkg/tcpip/transport/udp/udp_state_autogen.go
@@ -7,48 +7,49 @@ import (
 	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 )
 
-func (u *udpPacket) StateTypeName() string {
+func (p *udpPacket) StateTypeName() string {
 	return "pkg/tcpip/transport/udp.udpPacket"
 }
 
-func (u *udpPacket) StateFields() []string {
+func (p *udpPacket) StateFields() []string {
 	return []string{
 		"udpPacketEntry",
 		"senderAddress",
 		"destinationAddress",
 		"packetInfo",
 		"data",
-		"timestamp",
+		"receivedAt",
 		"tos",
 	}
 }
 
-func (u *udpPacket) beforeSave() {}
+func (p *udpPacket) beforeSave() {}
 
 // +checklocksignore
-func (u *udpPacket) StateSave(stateSinkObject state.Sink) {
-	u.beforeSave()
-	var dataValue buffer.VectorisedView = u.saveData()
+func (p *udpPacket) StateSave(stateSinkObject state.Sink) {
+	p.beforeSave()
+	var dataValue buffer.VectorisedView = p.saveData()
 	stateSinkObject.SaveValue(4, dataValue)
-	stateSinkObject.Save(0, &u.udpPacketEntry)
-	stateSinkObject.Save(1, &u.senderAddress)
-	stateSinkObject.Save(2, &u.destinationAddress)
-	stateSinkObject.Save(3, &u.packetInfo)
-	stateSinkObject.Save(5, &u.timestamp)
-	stateSinkObject.Save(6, &u.tos)
+	var receivedAtValue int64 = p.saveReceivedAt()
+	stateSinkObject.SaveValue(5, receivedAtValue)
+	stateSinkObject.Save(0, &p.udpPacketEntry)
+	stateSinkObject.Save(1, &p.senderAddress)
+	stateSinkObject.Save(2, &p.destinationAddress)
+	stateSinkObject.Save(3, &p.packetInfo)
+	stateSinkObject.Save(6, &p.tos)
 }
 
-func (u *udpPacket) afterLoad() {}
+func (p *udpPacket) afterLoad() {}
 
 // +checklocksignore
-func (u *udpPacket) StateLoad(stateSourceObject state.Source) {
-	stateSourceObject.Load(0, &u.udpPacketEntry)
-	stateSourceObject.Load(1, &u.senderAddress)
-	stateSourceObject.Load(2, &u.destinationAddress)
-	stateSourceObject.Load(3, &u.packetInfo)
-	stateSourceObject.Load(5, &u.timestamp)
-	stateSourceObject.Load(6, &u.tos)
-	stateSourceObject.LoadValue(4, new(buffer.VectorisedView), func(y interface{}) { u.loadData(y.(buffer.VectorisedView)) })
+func (p *udpPacket) StateLoad(stateSourceObject state.Source) {
+	stateSourceObject.Load(0, &p.udpPacketEntry)
+	stateSourceObject.Load(1, &p.senderAddress)
+	stateSourceObject.Load(2, &p.destinationAddress)
+	stateSourceObject.Load(3, &p.packetInfo)
+	stateSourceObject.Load(6, &p.tos)
+	stateSourceObject.LoadValue(4, new(buffer.VectorisedView), func(y interface{}) { p.loadData(y.(buffer.VectorisedView)) })
+	stateSourceObject.LoadValue(5, new(int64), func(y interface{}) { p.loadReceivedAt(y.(int64)) })
 }
 
 func (e *endpoint) StateTypeName() string {