fix(math): defend NewIntFromBigInt argument mutation (#17352)

(cherry picked from commit 658a88a)

# Conflicts:
#	math/CHANGELOG.md

math/CHANGELOG.md

@@ -31,5 +31,78 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ## [Unreleased]
 
+<<<<<<< HEAD
 * [#13381](https://github.com/cosmos/cosmos-sdk/pull/13381) Add uint `IsNil` method.
 * [#12634](https://github.com/cosmos/cosmos-sdk/pull/12634) Move `sdk.Dec` to math package, call it `LegacyDec`.
+=======
+## Improvements
+
+* [#17109](https://github.com/cosmos/cosmos-sdk/pull/17109) Add `.ToLegacyDec()` method on `math.Int` type for converting to `math.LegacyDec`.
+* [#16263](https://github.com/cosmos/cosmos-sdk/pull/16263) Improved `math/Int.Size` by computing the decimal digits count instead of firstly invoking .Marshal() then checking the length
+
+### Bug Fixes
+
+* [#17352](https://github.com/cosmos/cosmos-sdk/pull/17352) Ensure that modifying the argument to `NewIntFromBigInt` doesn't mutate the returned value.
+* [#16266](https://github.com/cosmos/cosmos-sdk/pull/16266) fix: legacy dec power mut zero exponent precision.
+
+## [math/v1.0.1](https://github.com/cosmos/cosmos-sdk/releases/tag/math/v1.0.1) - 2023-05-15
+
+### Improvements
+
+* [#15768](https://github.com/cosmos/cosmos-sdk/pull/15768) Removed the second call to the `init` method for the global variable `grand`.
+* [#16141](https://github.com/cosmos/cosmos-sdk/pull/16141) Speedup `LegacyDec.ApproxRoot` and `LegacyDec.ApproxSqrt`.
+
+### Bug Fixes
+
+* [#15714](https://github.com/cosmos/cosmos-sdk/pull/15714) `FormatInt` returns an error on empty string.
+
+## [math/v1.0.0](https://github.com/cosmos/cosmos-sdk/releases/tag/math/v1.0.0) - 2023-03-23
+
+### Bug Fixes
+
+* [#15506](https://github.com/cosmos/cosmos-sdk/issues/16605) Dec marshal shouldn't have side effects
+
+## [math/v1.0.0-rc.0](https://github.com/cosmos/cosmos-sdk/releases/tag/math/v1.0.0-rc.0) - 2023-03-13
+
+### Features
+
+* [#15043](https://github.com/cosmos/cosmos-sdk/issues/15043) add rand funcs to math
+
+### Bug Fixes
+
+* [#14922](https://github.com/cosmos/cosmos-sdk/issues/14922) check for negative precision
+
+### Testing
+
+* [#15215](https://github.com/cosmos/cosmos-sdk/issues/15215) fix `FormatDec` test
+
+## [math/v1.0.0-beta.6](https://github.com/cosmos/cosmos-sdk/releases/tag/math/v1.0.0-beta.6) - 2023-02-06
+
+### Features
+
+* [#14760](https://github.com/cosmos/cosmos-sdk/issues/14760) add collections key encoders and value encoders for common types.
+* [#14166](https://github.com/cosmos/cosmos-sdk/issues/14166) math: add generics versions of Max, Min to cater to all numeric types
+* [#13381](https://github.com/cosmos/cosmos-sdk/issues/13381) add uint `IsNil` method
+
+### Improvements
+
+* [#14010](https://github.com/cosmos/cosmos-sdk/issues/14010) math: optimize and test FormatInt + simplify LegacyNewDecFromStr
+* [#12794](https://github.com/cosmos/cosmos-sdk/issues/12794) math: precompute & use square of precisionReuse instead of 2 repeated computations
+
+### Bug Fixes
+
+* [#14691](https://github.com/cosmos/cosmos-sdk/issues/14691) do not flatten events attributes by event types
+* [#14252](https://github.com/cosmos/cosmos-sdk/issues/14252) math: add LegacyNewDecFromStr fuzzers + remove unnecessary error wrapping
+
+### Testing
+
+* [#14576](https://github.com/cosmos/cosmos-sdk/issues/14576) Added test cases for precisionMultiplier
+
+## [math/v1.0.0-beta.3](https://github.com/cosmos/cosmos-sdk/releases/tag/math/v1.0.0-beta.3) - 2022-07-20
+
+### Bug Fixes
+
+* [#11996](https://github.com/cosmos/cosmos-sdk/issues/11996) math: fix Uint.Unmarshal's lack of negative value checking
+
+<!-- generated by git-cliff -->
+>>>>>>> 658a88a30 (fix(math): defend NewIntFromBigInt argument mutation (#17352))

math/int.go

@@ -104,6 +104,7 @@ 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{}
@@ -112,7 +113,8 @@ 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