4 files changed, 72 insertions, 0 deletions
diff --git a/pkg/tcpip/tcpip.go b/pkg/tcpip/tcpip.go
index 07c85ce59..290c4e138 100644
--- a/pkg/tcpip/tcpip.go
+++ b/pkg/tcpip/tcpip.go
@@ -978,6 +978,15 @@ const (
 	TCPTimeWaitReuseLoopbackOnly
 )
 
+// LingerOption is used by SetSockOpt/GetSockOpt to set/get the
+// duration for which a socket lingers before returning from Close.
+//
+// +stateify savable
+type LingerOption struct {
+	Enabled bool
+	Timeout time.Duration
+}
+
 // IPPacketInfo is the message structure for IP_PKTINFO.
 //
 // +stateify savable
diff --git a/pkg/tcpip/tcpip_state_autogen.go b/pkg/tcpip/tcpip_state_autogen.go
index 827b27692..034b39c1f 100644
--- a/pkg/tcpip/tcpip_state_autogen.go
+++ b/pkg/tcpip/tcpip_state_autogen.go
@@ -111,6 +111,32 @@ func (x *LinkPacketInfo) StateLoad(m state.Source) {
 	m.Load(1, &x.PktType)
 }
 
+func (x *LingerOption) StateTypeName() string {
+	return "pkg/tcpip.LingerOption"
+}
+
+func (x *LingerOption) StateFields() []string {
+	return []string{
+		"Enabled",
+		"Timeout",
+	}
+}
+
+func (x *LingerOption) beforeSave() {}
+
+func (x *LingerOption) StateSave(m state.Sink) {
+	x.beforeSave()
+	m.Save(0, &x.Enabled)
+	m.Save(1, &x.Timeout)
+}
+
+func (x *LingerOption) afterLoad() {}
+
+func (x *LingerOption) StateLoad(m state.Source) {
+	m.Load(0, &x.Enabled)
+	m.Load(1, &x.Timeout)
+}
+
 func (x *IPPacketInfo) StateTypeName() string {
 	return "pkg/tcpip.IPPacketInfo"
 }
@@ -144,5 +170,6 @@ func init() {
 	state.Register((*FullAddress)(nil))
 	state.Register((*ControlMessages)(nil))
 	state.Register((*LinkPacketInfo)(nil))
+	state.Register((*LingerOption)(nil))
 	state.Register((*IPPacketInfo)(nil))
 }
diff --git a/pkg/tcpip/transport/tcp/endpoint.go b/pkg/tcpip/transport/tcp/endpoint.go
index 9c0f4c9f4..ff9b8804d 100644
--- a/pkg/tcpip/transport/tcp/endpoint.go
+++ b/pkg/tcpip/transport/tcp/endpoint.go
@@ -654,6 +654,9 @@ type endpoint struct {
 
 	// owner is used to get uid and gid of the packet.
 	owner tcpip.PacketOwner
+
+	// linger is used for SO_LINGER socket option.
+	linger tcpip.LingerOption
 }
 
 // UniqueID implements stack.TransportEndpoint.UniqueID.
@@ -1007,6 +1010,26 @@ func (e *endpoint) Close() {
 		return
 	}
 
+	if e.linger.Enabled && e.linger.Timeout == 0 {
+		s := e.EndpointState()
+		isResetState := s == StateEstablished || s == StateCloseWait || s == StateFinWait1 || s == StateFinWait2 || s == StateSynRecv
+		if isResetState {
+			// Close the endpoint without doing full shutdown and
+			// send a RST.
+			e.resetConnectionLocked(tcpip.ErrConnectionAborted)
+			e.closeNoShutdownLocked()
+
+			// Wake up worker to close the endpoint.
+			switch s {
+			case StateSynRecv:
+				e.notifyProtocolGoroutine(notifyClose)
+			default:
+				e.notifyProtocolGoroutine(notifyTickleWorker)
+			}
+			return
+		}
+	}
+
 	// Issue a shutdown so that the peer knows we won't send any more data
 	// if we're connected, or stop accepting if we're listening.
 	e.shutdownLocked(tcpip.ShutdownWrite | tcpip.ShutdownRead)
@@ -1807,6 +1830,11 @@ func (e *endpoint) SetSockOpt(opt interface{}) *tcpip.Error {
 	case tcpip.SocketDetachFilterOption:
 		return nil
 
+	case tcpip.LingerOption:
+		e.LockUser()
+		e.linger = v
+		e.UnlockUser()
+
 	default:
 		return nil
 	}
@@ -2032,6 +2060,11 @@ func (e *endpoint) GetSockOpt(opt interface{}) *tcpip.Error {
 			Port: port,
 		}
 
+	case *tcpip.LingerOption:
+		e.LockUser()
+		*o = e.linger
+		e.UnlockUser()
+
 	default:
 		return tcpip.ErrUnknownProtocolOption
 	}
diff --git a/pkg/tcpip/transport/tcp/tcp_state_autogen.go b/pkg/tcpip/transport/tcp/tcp_state_autogen.go
index bed45e9a1..77e0d0e97 100644
--- a/pkg/tcpip/transport/tcp/tcp_state_autogen.go
+++ b/pkg/tcpip/transport/tcp/tcp_state_autogen.go
@@ -222,6 +222,7 @@ func (x *endpoint) StateFields() []string {
 		"closed",
 		"txHash",
 		"owner",
+		"linger",
 	}
 }
 
@@ -293,6 +294,7 @@ func (x *endpoint) StateSave(m state.Sink) {
 	m.Save(59, &x.closed)
 	m.Save(60, &x.txHash)
 	m.Save(61, &x.owner)
+	m.Save(62, &x.linger)
 }
 
 func (x *endpoint) StateLoad(m state.Source) {
@@ -354,6 +356,7 @@ func (x *endpoint) StateLoad(m state.Source) {
 	m.Load(59, &x.closed)
 	m.Load(60, &x.txHash)
 	m.Load(61, &x.owner)
+	m.Load(62, &x.linger)
 	m.LoadValue(3, new(string), func(y interface{}) { x.loadLastError(y.(string)) })
 	m.LoadValue(10, new(EndpointState), func(y interface{}) { x.loadState(y.(EndpointState)) })
 	m.LoadValue(25, new(unixTime), func(y interface{}) { x.loadRecentTSTime(y.(unixTime)) })