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Merged
gzliudan merged 1 commit into from
Sep 3, 2025
Merged

accounts/abi: error when packing negative values in unsigned types #31790 #1422

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19 changes: 10 additions & 9 deletions accounts/abi/error_handling.go
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Original file line number Diff line number Diff line change
Expand Up @@ -23,15 +23,16 @@ import (
)

var (
errBadBool = errors.New("abi: improperly encoded boolean value")
errBadUint8 = errors.New("abi: improperly encoded uint8 value")
errBadUint16 = errors.New("abi: improperly encoded uint16 value")
errBadUint32 = errors.New("abi: improperly encoded uint32 value")
errBadUint64 = errors.New("abi: improperly encoded uint64 value")
errBadInt8 = errors.New("abi: improperly encoded int8 value")
errBadInt16 = errors.New("abi: improperly encoded int16 value")
errBadInt32 = errors.New("abi: improperly encoded int32 value")
errBadInt64 = errors.New("abi: improperly encoded int64 value")
errBadBool = errors.New("abi: improperly encoded boolean value")
errBadUint8 = errors.New("abi: improperly encoded uint8 value")
errBadUint16 = errors.New("abi: improperly encoded uint16 value")
errBadUint32 = errors.New("abi: improperly encoded uint32 value")
errBadUint64 = errors.New("abi: improperly encoded uint64 value")
errBadInt8 = errors.New("abi: improperly encoded int8 value")
errBadInt16 = errors.New("abi: improperly encoded int16 value")
errBadInt32 = errors.New("abi: improperly encoded int32 value")
errBadInt64 = errors.New("abi: improperly encoded int64 value")
errInvalidSign = errors.New("abi: negatively-signed value cannot be packed into uint parameter")
)

// formatSliceString formats the reflection kind with the given slice size
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11 changes: 10 additions & 1 deletion accounts/abi/pack.go
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Original file line number Diff line number Diff line change
Expand Up @@ -37,7 +37,16 @@ func packBytesSlice(bytes []byte, l int) []byte {
// t.
func packElement(t Type, reflectValue reflect.Value) ([]byte, error) {
switch t.T {
case IntTy, UintTy:
case UintTy:
// make sure to not pack a negative value into a uint type.
if reflectValue.Kind() == reflect.Ptr {
val := new(big.Int).Set(reflectValue.Interface().(*big.Int))
if val.Sign() == -1 {
return nil, errInvalidSign
}
}
return packNum(reflectValue), nil
case IntTy:
return packNum(reflectValue), nil
case StringTy:
return packBytesSlice([]byte(reflectValue.String()), reflectValue.Len()), nil
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5 changes: 5 additions & 0 deletions accounts/abi/pack_test.go
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Original file line number Diff line number Diff line change
Expand Up @@ -177,6 +177,11 @@ func TestMethodPack(t *testing.T) {
if !bytes.Equal(packed, sig) {
t.Errorf("expected %x got %x", sig, packed)
}

// test that we can't pack a negative value for a parameter that is specified as a uint
if _, err := abi.Pack("send", big.NewInt(-1)); err == nil {
t.Fatal("expected error when trying to pack negative big.Int into uint256 value")
}
}

func TestPackNumber(t *testing.T) {
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66 changes: 36 additions & 30 deletions accounts/abi/unpack_test.go
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Expand Up @@ -974,128 +974,134 @@ func TestPackAndUnpackIncompatibleNumber(t *testing.T) {
cases := []struct {
decodeType string
inputValue *big.Int
err error
unpackErr error
packErr error
expectValue interface{}
}{
{
decodeType: "uint8",
inputValue: big.NewInt(math.MaxUint8 + 1),
err: errBadUint8,
unpackErr: errBadUint8,
},
{
decodeType: "uint8",
inputValue: big.NewInt(math.MaxUint8),
err: nil,
unpackErr: nil,
expectValue: uint8(math.MaxUint8),
},
{
decodeType: "uint16",
inputValue: big.NewInt(math.MaxUint16 + 1),
err: errBadUint16,
unpackErr: errBadUint16,
},
{
decodeType: "uint16",
inputValue: big.NewInt(math.MaxUint16),
err: nil,
unpackErr: nil,
expectValue: uint16(math.MaxUint16),
},
{
decodeType: "uint32",
inputValue: big.NewInt(math.MaxUint32 + 1),
err: errBadUint32,
unpackErr: errBadUint32,
},
{
decodeType: "uint32",
inputValue: big.NewInt(math.MaxUint32),
err: nil,
unpackErr: nil,
expectValue: uint32(math.MaxUint32),
},
{
decodeType: "uint64",
inputValue: maxU64Plus1,
err: errBadUint64,
unpackErr: errBadUint64,
},
{
decodeType: "uint64",
inputValue: maxU64,
err: nil,
unpackErr: nil,
expectValue: uint64(math.MaxUint64),
},
{
decodeType: "uint256",
inputValue: maxU64Plus1,
err: nil,
unpackErr: nil,
expectValue: maxU64Plus1,
},
{
decodeType: "int8",
inputValue: big.NewInt(math.MaxInt8 + 1),
err: errBadInt8,
unpackErr: errBadInt8,
},
{
decodeType: "int8",
inputValue: big.NewInt(math.MinInt8 - 1),
err: errBadInt8,
packErr: errInvalidSign,
},
{
decodeType: "int8",
inputValue: big.NewInt(math.MaxInt8),
err: nil,
unpackErr: nil,
expectValue: int8(math.MaxInt8),
},
{
decodeType: "int16",
inputValue: big.NewInt(math.MaxInt16 + 1),
err: errBadInt16,
unpackErr: errBadInt16,
},
{
decodeType: "int16",
inputValue: big.NewInt(math.MinInt16 - 1),
err: errBadInt16,
packErr: errInvalidSign,
},
{
decodeType: "int16",
inputValue: big.NewInt(math.MaxInt16),
err: nil,
unpackErr: nil,
expectValue: int16(math.MaxInt16),
},
{
decodeType: "int32",
inputValue: big.NewInt(math.MaxInt32 + 1),
err: errBadInt32,
unpackErr: errBadInt32,
},
{
decodeType: "int32",
inputValue: big.NewInt(math.MinInt32 - 1),
err: errBadInt32,
packErr: errInvalidSign,
},
{
decodeType: "int32",
inputValue: big.NewInt(math.MaxInt32),
err: nil,
unpackErr: nil,
expectValue: int32(math.MaxInt32),
},
{
decodeType: "int64",
inputValue: new(big.Int).Add(big.NewInt(math.MaxInt64), big.NewInt(1)),
err: errBadInt64,
unpackErr: errBadInt64,
},
{
decodeType: "int64",
inputValue: new(big.Int).Sub(big.NewInt(math.MinInt64), big.NewInt(1)),
err: errBadInt64,
packErr: errInvalidSign,
},
{
decodeType: "int64",
inputValue: big.NewInt(math.MaxInt64),
err: nil,
unpackErr: nil,
expectValue: int64(math.MaxInt64),
},
}
for i, testCase := range cases {
packed, err := encodeABI.Pack(testCase.inputValue)
if err != nil {
panic(err)
if testCase.packErr != nil {
if err == nil {
t.Fatalf("expected packing of testcase input value to fail")
}
if err != testCase.packErr {
t.Fatalf("expected error '%v', got '%v'", testCase.packErr, err)
}
continue
}
if err != nil && err != testCase.packErr {
panic(fmt.Errorf("unexpected error packing test-case input: %v", err))
}
ty, err := NewType(testCase.decodeType, "", nil)
if err != nil {
Expand All @@ -1105,8 +1111,8 @@ func TestPackAndUnpackIncompatibleNumber(t *testing.T) {
{Type: ty},
}
decoded, err := decodeABI.Unpack(packed)
if err != testCase.err {
t.Fatalf("Expected error %v, actual error %v. case %d", testCase.err, err, i)
if err != testCase.unpackErr {
t.Fatalf("Expected error %v, actual error %v. case %d", testCase.unpackErr, err, i)
}
if err != nil {
continue
Expand Down