From de0708b40171225d00fc3fe59717efd3280c20c2 Mon Sep 17 00:00:00 2001
From: Facundo Medica <14063057+facundomedica@users.noreply.github.com>
Date: Wed, 31 Jul 2024 17:15:17 +0200
Subject: [PATCH] fix(x/tx): concurrent map writes when calling GetSigners
 (#21073)

---
 simapp/app.go                |  4 ++++
 x/tx/CHANGELOG.md            |  4 ++++
 x/tx/signing/context.go      | 12 ++++++++----
 x/tx/signing/context_test.go | 15 +++++++++++++++
 4 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/simapp/app.go b/simapp/app.go
index 092435e4781c..6c2424e29c60 100644
--- a/simapp/app.go
+++ b/simapp/app.go
@@ -214,6 +214,10 @@ func NewSimApp(
 	signingCtx := interfaceRegistry.SigningContext()
 	txConfig := authtx.NewTxConfig(appCodec, signingCtx.AddressCodec(), signingCtx.ValidatorAddressCodec(), authtx.DefaultSignModes)
 
+	if err := signingCtx.Validate(); err != nil {
+		panic(err)
+	}
+
 	std.RegisterLegacyAminoCodec(legacyAmino)
 	std.RegisterInterfaces(interfaceRegistry)
 
diff --git a/x/tx/CHANGELOG.md b/x/tx/CHANGELOG.md
index af095740513d..4a13d399cab3 100644
--- a/x/tx/CHANGELOG.md
+++ b/x/tx/CHANGELOG.md
@@ -33,6 +33,10 @@ Since v0.13.0, x/tx follows Cosmos SDK semver: https://github.com/cosmos/cosmos-
 
 ## [Unreleased]
 
+### Improvements
+
+* [#21073](https://github.com/cosmos/cosmos-sdk/pull/21073) In Context use sync.Map `getSignersFuncs` map from concurrent writes, we also call Validate when creating the Context.
+
 ## [v0.13.3](https://github.com/cosmos/cosmos-sdk/releases/tag/x/tx/v0.13.3) - 2024-04-22
 
 ### Improvements
diff --git a/x/tx/signing/context.go b/x/tx/signing/context.go
index 7aca6fd2b1cd..f44be0118cca 100644
--- a/x/tx/signing/context.go
+++ b/x/tx/signing/context.go
@@ -3,6 +3,7 @@ package signing
 import (
 	"errors"
 	"fmt"
+	"sync"
 
 	cosmos_proto "github.com/cosmos/cosmos-proto"
 	gogoproto "github.com/cosmos/gogoproto/proto"
@@ -29,7 +30,7 @@ type Context struct {
 	typeResolver          protoregistry.MessageTypeResolver
 	addressCodec          address.Codec
 	validatorAddressCodec address.Codec
-	getSignersFuncs       map[protoreflect.FullName]GetSignersFunc
+	getSignersFuncs       sync.Map
 	customGetSignerFuncs  map[protoreflect.FullName]GetSignersFunc
 	maxRecursionDepth     int
 }
@@ -110,7 +111,7 @@ func NewContext(options Options) (*Context, error) {
 		typeResolver:          protoTypes,
 		addressCodec:          options.AddressCodec,
 		validatorAddressCodec: options.ValidatorAddressCodec,
-		getSignersFuncs:       map[protoreflect.FullName]GetSignersFunc{},
+		getSignersFuncs:       sync.Map{},
 		customGetSignerFuncs:  customGetSignerFuncs,
 		maxRecursionDepth:     options.MaxRecursionDepth,
 	}
@@ -334,14 +335,17 @@ func (c *Context) getGetSignersFn(messageDescriptor protoreflect.MessageDescript
 	if ok {
 		return f, nil
 	}
-	f, ok = c.getSignersFuncs[messageDescriptor.FullName()]
+
+	loadedFn, ok := c.getSignersFuncs.Load(messageDescriptor.FullName())
 	if !ok {
 		var err error
 		f, err = c.makeGetSignersFunc(messageDescriptor)
 		if err != nil {
 			return nil, err
 		}
-		c.getSignersFuncs[messageDescriptor.FullName()] = f
+		c.getSignersFuncs.Store(messageDescriptor.FullName(), f)
+	} else {
+		f = loadedFn.(GetSignersFunc)
 	}
 
 	return f, nil
diff --git a/x/tx/signing/context_test.go b/x/tx/signing/context_test.go
index d8c2b370333a..88f0bf4aadf9 100644
--- a/x/tx/signing/context_test.go
+++ b/x/tx/signing/context_test.go
@@ -51,6 +51,21 @@ var deeplyNestedRepeatedSigner = &testpb.DeeplyNestedRepeatedSigner{
 	},
 }
 
+func TestGetGetSignersFnConcurrent(t *testing.T) {
+	ctx, err := NewContext(Options{
+		AddressCodec:          dummyAddressCodec{},
+		ValidatorAddressCodec: dummyValidatorAddressCodec{},
+	})
+	require.NoError(t, err)
+
+	desc := (&testpb.RepeatedSigner{}).ProtoReflect().Descriptor()
+	for i := 0; i < 50; i++ {
+		go func() {
+			_, _ = ctx.getGetSignersFn(desc)
+		}()
+	}
+}
+
 func TestGetSigners(t *testing.T) {
 	ctx, err := NewContext(Options{
 		AddressCodec:          dummyAddressCodec{},