fix seg fault on raced bytes array (#1778)

go.mod

@@ -225,7 +225,7 @@ require (
 	golang.org/x/crypto v0.21.0 // indirect
 	golang.org/x/exp v0.0.0-20230905200255-921286631fa9
 	golang.org/x/net v0.23.0
-	golang.org/x/sync v0.6.0 // indirect
+	golang.org/x/sync v0.6.0
 	golang.org/x/sys v0.20.0 // indirect
 	golang.org/x/term v0.18.0
 	golang.org/x/text v0.14.0 // indirect

utils/sigs/sigs.go

@@ -112,21 +112,6 @@ func EncodeUint64(val uint64) []byte {
 	return encodedVal
 }
 
-// Join() is faster than bytes.Join because it does what
-// bytes.Join() does without appending (empty) separators
-func Join(s [][]byte) []byte {
-	n := 0
-	for _, v := range s {
-		n += len(v)
-	}
-
-	b, i := make([]byte, n), 0
-	for _, v := range s {
-		i += copy(b[i:], v)
-	}
-	return b
-}
-
 func GetKeyName(clientCtx client.Context) (string, error) {
 	_, name, _, err := client.GetFromFields(clientCtx, clientCtx.Keyring, clientCtx.From)
 	if err != nil {

x/conflict/types/relay_finalization.go

@@ -1,6 +1,7 @@
 package types
 
 import (
+	"bytes"
 	"encoding/json"
 	fmt "fmt"
 
@@ -55,7 +56,7 @@ func (rf RelayFinalization) DataToSign() []byte {
 		sdkAccAddress,
 		relaySessionHash,
 	}
-	return sigs.Join(msgParts)
+	return bytes.Join(msgParts, nil)
 }
 
 func (rfm RelayFinalization) HashRounds() int {

x/pairing/types/relay_exchange.go

@@ -1,6 +1,7 @@
 package types
 
 import (
+	"bytes"
 	"strings"
 
 	"github.com/lavanet/lava/v4/utils"
@@ -39,7 +40,7 @@ func (re RelayExchange) DataToSign() []byte {
 		metadataBytes,
 	}
 
-	return sigs.Join(msgParts)
+	return bytes.Join(msgParts, nil)
 }
 
 func (re RelayExchange) HashRounds() int {
@@ -65,6 +66,5 @@ func (rp RelayPrivateData) GetContentHashData() []byte {
 		seenBlockBytes,
 		rp.Salt,
 	}
-	msgData := sigs.Join(msgParts)
-	return msgData
+	return bytes.Join(msgParts, nil)
 }

x/pairing/types/relay_exchange_test.go

@@ -0,0 +1,113 @@
+package types
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestGetContentHashData_NilInputs(t *testing.T) {
+	// Test case with all nil/empty values
+	rp := RelayPrivateData{
+		Metadata:       nil,
+		Extensions:     nil,
+		Addon:          "",
+		ApiInterface:   "",
+		ConnectionType: "",
+		ApiUrl:         "",
+		Data:           nil,
+		Salt:           nil,
+		RequestBlock:   0,
+		SeenBlock:      0,
+	}
+
+	// Function should not panic and return a valid byte slice
+	result := rp.GetContentHashData()
+	require.NotNil(t, result)
+
+	// Test with nil Extensions but non-nil empty slice
+	rp.Extensions = []string{}
+	result = rp.GetContentHashData()
+	require.NotNil(t, result)
+
+	// Test with nil Metadata but non-nil empty slice
+	rp.Metadata = []Metadata{}
+	result = rp.GetContentHashData()
+	require.NotNil(t, result)
+}
+
+func TestGetContentHashData_NilData(t *testing.T) {
+	// Test case with nil Data field specifically
+	rp := RelayPrivateData{
+		Metadata:       []Metadata{},
+		Extensions:     []string{},
+		Addon:          "",
+		ApiInterface:   "",
+		ConnectionType: "",
+		ApiUrl:         "",
+		Data:           nil, // Explicitly nil
+		Salt:           make([]byte, 8),
+		RequestBlock:   0,
+		SeenBlock:      0,
+	}
+
+	// Function should not panic
+	result := rp.GetContentHashData()
+	require.NotNil(t, result)
+}
+
+func TestGetContentHashData_EdgeCases(t *testing.T) {
+	testCases := []struct {
+		name string
+		rp   RelayPrivateData
+	}{
+		{
+			name: "nil metadata with data",
+			rp: RelayPrivateData{
+				Metadata: nil,
+				Data:     []byte("test"),
+			},
+		},
+		{
+			name: "nil extensions with data",
+			rp: RelayPrivateData{
+				Extensions: nil,
+				Data:       []byte("test"),
+			},
+		},
+		{
+			name: "nil everything",
+			rp: RelayPrivateData{
+				Metadata:       nil,
+				Extensions:     nil,
+				Addon:          "",
+				ApiInterface:   "",
+				ConnectionType: "",
+				ApiUrl:         "",
+				Data:           nil,
+				Salt:           nil,
+			},
+		},
+		{
+			name: "empty strings with nil slices",
+			rp: RelayPrivateData{
+				Metadata:       []Metadata{},
+				Extensions:     []string{},
+				Addon:          "",
+				ApiInterface:   "",
+				ConnectionType: "",
+				ApiUrl:         "",
+				Data:           nil,
+				Salt:           nil,
+			},
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			// Function should not panic
+			result := tc.rp.GetContentHashData()
+			require.NotNil(t, result)
+		})
+	}
+}

x/pairing/types/relay_session.go

@@ -1,6 +1,8 @@
 package types
 
 import (
+	"bytes"
+
 	"github.com/lavanet/lava/v4/utils/sigs"
 )
 
@@ -28,5 +30,5 @@ func (rs RelaySession) CalculateHashForFinalization() []byte {
 		blockHeightBytes,
 		relayNumBytes,
 	}
-	return sigs.Join(msgParts)
+	return bytes.Join(msgParts, nil)
 }