chore(runway): cherry-pick fix: cp-7.61.0 Perps eligibility refresh race condition causing users to be incorrectly geo-blocked (#23908)

- fix: cp-7.61.0 Perps eligibility refresh race condition causing users
to be incorrectly geo-blocked (#23895)

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## **Description**
Fix race condition causing users to be geo-blocked incorrectly.

The Bug: `refreshEligibility()` is called with fallback regions but
isn't awaited — so the constructor continues, updates to remote config,
and starts new eligibility checks. The fallback check finishes last and
overwrites the correct remote result with false.

Workaround: a version counter ensures stale checks (started before the
config changed) are discarded when they complete.

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CHANGELOG entry: fix perps refreshEligibility race condition causing
users to be geo-blocked

## **Related issues**

Fixes:

## **Manual testing steps**

```gherkin
Feature: my feature name

  Scenario: user [verb for user action]
    Given [describe expected initial app state]

    When user [verb for user action]
    Then [describe expected outcome]
```

## **Screenshots/Recordings**

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### **Before**

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### **After**

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- [x] I’ve followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask Mobile
Coding

Standards](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [x] I've completed the PR template to the best of my ability
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<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Adds a version counter to blocked region config and updates
refreshEligibility to ignore stale checks so fallback results don’t
overwrite remote-based eligibility.
> 
> - **PerpsController
(`app/components/UI/Perps/controllers/PerpsController.ts`)**:
>   - **Race-condition fix for eligibility**:
>     - Add `blockedRegionListVersion` to version blocked region config.
> - Increment version when blocked regions are set via
`setBlockedRegionList` and on feature flag changes.
> - Update `refreshEligibility` to capture start version and only update
`state.isEligible` if the version is unchanged (including error path).
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
92f5d33. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

---------

Co-authored-by: Nicholas Gambino <nicholas.gambino@consensys.net>
[fa1b19f](fa1b19f)

Co-authored-by: Matthew Grainger <46547583+Matt561@users.noreply.github.com>
Co-authored-by: Nicholas Gambino <nicholas.gambino@consensys.net>
Co-authored-by: João Loureiro <175489935+joaoloureirop@users.noreply.github.com>

Author: 4 people

app/components/UI/Perps/controllers/PerpsController.ts

@@ -633,6 +633,14 @@ export class PerpsController extends BaseController<
     source: 'fallback',
   };
 
+  /**
+   * Version counter for blocked region list.
+   * Used to prevent race conditions where stale eligibility checks
+   * (started with fallback config) overwrite results from newer checks
+   * (started with remote config).
+   */
+  private blockedRegionListVersion = 0;
+
   // Store HIP-3 configuration (mutable for runtime updates from remote flags)
   private hip3Enabled: boolean;
   private hip3AllowlistMarkets: string[];
@@ -713,6 +721,7 @@ export class PerpsController extends BaseController<
           newSource: 'remote' | 'fallback',
         ) => {
           this.blockedRegionList = { list: newList, source: newSource };
+          this.blockedRegionListVersion += 1;
         },
         refreshEligibility: () => this.refreshEligibility(),
       }),
@@ -739,6 +748,7 @@ export class PerpsController extends BaseController<
             source: 'remote' | 'fallback',
           ) => {
             this.blockedRegionList = { list, source };
+            this.blockedRegionListVersion += 1;
           },
           refreshEligibility: () => this.refreshEligibility(),
           getHip3Config: () => ({
@@ -2099,13 +2109,25 @@ export class PerpsController extends BaseController<
    * Refresh eligibility status
    */
   async refreshEligibility(): Promise<void> {
-    try {
-      DevLogger.log('PerpsController: Refreshing eligibility');
+    // Capture the current version before starting the async operation.
+    // This prevents race conditions where stale eligibility checks
+    // (started with fallback config) overwrite results from newer checks
+    // (started with remote config after it was fetched).
+    const versionAtStart = this.blockedRegionListVersion;
 
+    try {
+      // TODO: It would be good to have this location before we call this async function to avoid the race condition
       const isEligible = await EligibilityService.checkEligibility(
         this.blockedRegionList.list,
       );
 
+      // Only update state if the blocked region list hasn't changed while we were awaiting.
+      // This prevents stale fallback-based eligibility checks from overwriting
+      // results from remote-based checks.
+      if (this.blockedRegionListVersion !== versionAtStart) {
+        return;
+      }
+
       this.update((state) => {
         state.isEligible = isEligible;
       });
@@ -2114,10 +2136,14 @@ export class PerpsController extends BaseController<
         ensureError(error),
         this.getErrorContext('refreshEligibility'),
       );
-      // Default to eligible on error
-      this.update((state) => {
-        state.isEligible = true;
-      });
+
+      // Only update on error if version is still current
+      if (this.blockedRegionListVersion === versionAtStart) {
+        // Default to eligible on error
+        this.update((state) => {
+          state.isEligible = true;
+        });
+      }
     }
   }