fix(math): Backport of pull requests cosmos#17352 and cosmos#18214

math/CHANGELOG.md

@@ -39,7 +39,9 @@ Ref: https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.j
 ### Bug Fixes
 
 * [#16266](https://github.com/cosmos/cosmos-sdk/pull/16266) fix: legacy dec power mut zero exponent precision.
+* [#17352](https://github.com/cosmos/cosmos-sdk/pull/17352) Ensure that modifying the argument to `NewIntFromBigInt` doesn't mutate the returned value.
 * [#18211](https://github.com/cosmos/cosmos-sdk/pull/18211) RelativePow now returns 1 when 0^0, before it was returning the scale factor.
+* [#18214](https://github.com/cosmos/cosmos-sdk/pull/18214) Ensure that modifying the argument to 
 
 ## [math/v1.0.1](https://github.com/cosmos/cosmos-sdk/releases/tag/math/v1.0.1) - 2023-05-15
 

math/int.go

@@ -105,6 +105,7 @@ func NewIntFromUint64(n uint64) Int {
 
 // NewIntFromBigInt constructs Int from big.Int. If the provided big.Int is nil,
 // it returns an empty instance. This function panics if the bit length is > 256.
+// Note, the caller can safely mutate the argument after this function returns.
 func NewIntFromBigInt(i *big.Int) Int {
 	if i == nil {
 		return Int{}
@@ -113,7 +114,7 @@ func NewIntFromBigInt(i *big.Int) Int {
 	if i.BitLen() > MaxBitLen {
 		panic("NewIntFromBigInt() out of bound")
 	}
-	return Int{i}
+	return Int{new(big.Int).Set(i)}
 }
 
 // NewIntFromString constructs Int from string

math/int_test.go

@@ -43,6 +43,19 @@ func (s *intTestSuite) TestFromUint64() {
 	}
 }
 
+func (s *intTestSuite) TestNewIntFromBigInt() {
+	i := math.NewIntFromBigInt(nil)
+	s.Require().True(i.IsNil())
+
+	r := big.NewInt(42)
+	i = math.NewIntFromBigInt(r)
+	s.Require().Equal(r, i.BigInt())
+
+	// modify r and ensure i doesn't change
+	r = r.SetInt64(100)
+	s.Require().NotEqual(r, i.BigInt())
+}
+
 func (s *intTestSuite) TestIntPanic() {
 	// Max Int = 2^256-1 = 1.1579209e+77
 	// Min Int = -(2^256-1) = -1.1579209e+77

math/uint.go

@@ -235,7 +235,7 @@ func checkNewUint(i *big.Int) (Uint, error) {
 	if err := UintOverflow(i); err != nil {
 		return Uint{}, err
 	}
-	return Uint{i}, nil
+	return Uint{new(big.Int).Set(i)}, nil
 }
 
 // RelativePow raises x to the power of n, where x (and the result, z) are scaled by factor b

math/uint_test.go

@@ -261,6 +261,16 @@ func (s *uintTestSuite) TestParseUint() {
 	}
 }
 
+func (s *uintTestSuite) TestNewUintFromBigInt() {
+	r := big.NewInt(42)
+	i := sdkmath.NewUintFromBigInt(r)
+	s.Require().Equal(r, i.BigInt())
+
+	// modify r and ensure i doesn't change
+	r = r.SetInt64(100)
+	s.Require().NotEqual(r, i.BigInt())
+}
+
 func randuint() sdkmath.Uint {
 	return sdkmath.NewUint(rand.Uint64())
 }