go: use deadlock.Mutex to check for deadlocks

Signed-off-by: David Scott <dave@recoil.org>

go.mod

@@ -52,7 +52,9 @@ require (
 	github.com/modern-go/reflect2 v0.0.0-20180701023420-4b7aa43c6742 // indirect
 	github.com/pelletier/go-toml v1.4.0 // indirect
 	github.com/peterbourgon/diskv v2.0.1+incompatible // indirect
+	github.com/petermattis/goid v0.0.0-20180202154549-b0b1615b78e5 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/sasha-s/go-deadlock v0.3.1 // indirect
 	github.com/spf13/afero v1.2.2 // indirect
 	github.com/spf13/cast v1.3.0 // indirect
 	github.com/spf13/jwalterweatherman v1.1.0 // indirect

go.sum

@@ -122,6 +122,8 @@ github.com/pelletier/go-toml v1.4.0 h1:u3Z1r+oOXJIkxqw34zVhyPgjBsm6X2wn21NWs/HfS
 github.com/pelletier/go-toml v1.4.0/go.mod h1:PN7xzY2wHTK0K9p34ErDQMlFxa51Fk0OUruD3k1mMwo=
 github.com/peterbourgon/diskv v2.0.1+incompatible h1:UBdAOUP5p4RWqPBg048CAvpKN+vxiaj6gdUUzhl4XmI=
 github.com/peterbourgon/diskv v2.0.1+incompatible/go.mod h1:uqqh8zWWbv1HBMNONnaR/tNboyR3/BZd58JJSHlUSCU=
+github.com/petermattis/goid v0.0.0-20180202154549-b0b1615b78e5 h1:q2e307iGHPdTGp0hoxKjt1H5pDo6utceo3dQVK3I5XQ=
+github.com/petermattis/goid v0.0.0-20180202154549-b0b1615b78e5/go.mod h1:jvVRKCrJTQWu0XVbaOlby/2lO20uSCHEMzzplHXte1o=
 github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.8.1-0.20181023235946-059132a15dd0 h1:TVdhkEP0WKajbywS5TEDWwuzCl9EqOcQ6b1ymfmx/6E=
 github.com/pkg/errors v0.8.1-0.20181023235946-059132a15dd0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
@@ -137,6 +139,8 @@ github.com/prometheus/procfs v0.0.0-20181005140218-185b4288413d/go.mod h1:c3At6R
 github.com/prometheus/procfs v0.0.0-20190507164030-5867b95ac084/go.mod h1:TjEm7ze935MbeOT/UhFTIMYKhuLP4wbCsTZCD3I8kEA=
 github.com/prometheus/tsdb v0.7.1/go.mod h1:qhTCs0VvXwvX/y3TZrWD7rabWM+ijKTux40TwIPHuXU=
 github.com/rogpeppe/fastuuid v0.0.0-20150106093220-6724a57986af/go.mod h1:XWv6SoW27p1b0cqNHllgS5HIMJraePCO15w5zCzIWYg=
+github.com/sasha-s/go-deadlock v0.3.1 h1:sqv7fDNShgjcaxkO0JNcOAlr8B9+cV5Ey/OB71efZx0=
+github.com/sasha-s/go-deadlock v0.3.1/go.mod h1:F73l+cr82YSh10GxyRI6qZiCgK64VaZjwesgfQ1/iLM=
 github.com/sirupsen/logrus v1.2.0/go.mod h1:LxeOpSwHxABJmUn/MG1IvRgCAasNZTLOkJPxbbu5VWo=
 github.com/sirupsen/logrus v1.3.0 h1:hI/7Q+DtNZ2kINb6qt/lS+IyXnHQe9e90POfeewL/ME=
 github.com/sirupsen/logrus v1.3.0/go.mod h1:LxeOpSwHxABJmUn/MG1IvRgCAasNZTLOkJPxbbu5VWo=

go/pkg/libproxy/loopbackconn.go

@@ -5,6 +5,8 @@ import (
 	"net"
 	"sync"
 	"time"
+
+	"github.com/sasha-s/go-deadlock"
 )
 
 // io.Pipe is synchronous but we need to decouple the Read and Write calls
@@ -19,7 +21,7 @@ import (
 type bufferedPipe struct {
 	bufs         [][]byte
 	eof          bool
-	m            sync.Mutex
+	m            deadlock.Mutex
 	c            *sync.Cond
 	readDeadline time.Time
 }

go/pkg/libproxy/multiplexed.go

@@ -11,6 +11,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/sasha-s/go-deadlock"
 	"golang.org/x/sync/errgroup"
 )
 
@@ -39,7 +40,7 @@ func (w *windowState) advance() {
 }
 
 type channel struct {
-	m             sync.Mutex
+	m             deadlock.Mutex
 	c             *sync.Cond
 	multiplexer   *multiplexer
 	destination   Destination
@@ -357,15 +358,15 @@ type multiplexer struct {
 	conn              io.Closer
 	connR             io.Reader // with buffering
 	connW             *bufio.Writer
-	writeMutex        sync.Mutex // hold when writing on the channel
+	writeMutex        deadlock.Mutex // hold when writing on the channel
 	channels          map[uint32]*channel
 	nextChannelID     uint32
-	metadataMutex     sync.Mutex // hold when reading/modifying this structure
-	pendingAccept     []*channel // incoming connections
+	metadataMutex     deadlock.Mutex // hold when reading/modifying this structure
+	pendingAccept     []*channel     // incoming connections
 	acceptCond        *sync.Cond
 	isRunning         bool
 	events            *ring.Ring // log of packetEvents
-	eventsM           sync.Mutex
+	eventsM           deadlock.Mutex
 	allocateBackwards bool
 }
 

go/pkg/libproxy/multiplexed_test.go

@@ -12,6 +12,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/sasha-s/go-deadlock"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"golang.org/x/sync/errgroup"
@@ -492,7 +493,7 @@ func TestMuxConcurrent(t *testing.T) {
 	serverReadSha := make(map[uint16]string)
 	clientWriteSha := make(map[uint16]string)
 	clientReadSha := make(map[uint16]string)
-	m := &sync.Mutex{}
+	m := &deadlock.Mutex{}
 	wg.Add(numConcurrent)
 	for i := 0; i < numConcurrent; i++ {
 		go func(i int) {

go/pkg/libproxy/udp_encapsulation.go

@@ -6,8 +6,9 @@ import (
 	"errors"
 	"io"
 	"net"
-	"sync"
 	"time"
+
+	"github.com/sasha-s/go-deadlock"
 )
 
 // UDPListener defines a listener interface to read, write and close a UDP connection
@@ -28,9 +29,9 @@ type uDPEncapsulator interface {
 // udpEncapsulator encapsulates a UDP connection and listener
 type udpEncapsulator struct {
 	conn net.Conn
-	m    sync.Mutex
-	r    sync.Mutex
-	w    sync.Mutex
+	m    deadlock.Mutex
+	r    deadlock.Mutex
+	w    deadlock.Mutex
 	addr *net.UDPAddr
 }
 

go/pkg/libproxy/udp_proxy.go

@@ -4,9 +4,10 @@ import (
 	"encoding/binary"
 	"net"
 	"strings"
-	"sync"
 	"syscall"
 	"time"
+
+	"github.com/sasha-s/go-deadlock"
 )
 
 const (
@@ -50,7 +51,7 @@ type UDPProxy struct {
 	backendAddr    *net.UDPAddr
 	dialer         UDPDialer
 	connTrackTable connTrackMap
-	connTrackLock  sync.Mutex
+	connTrackLock  deadlock.Mutex
 }
 
 // UDPDialer creates UDP (pseudo-)connections to an address