fix: fix CancellationTokenSource leak in StartingSyncPivotUpdater (#10859)

ninastef · LukaszRozmej · web-flow · commit fb21e6424fea · 2026-03-19T15:07:42.000+01:00
* Update StartingSyncPivotUpdater.cs * Apply suggestion from @LukaszRozmej Co-authored-by: Lukasz Rozmej <lukasz.rozmej@gmail.com> * Apply suggestion from @LukaszRozmej Co-authored-by: Lukasz Rozmej <lukasz.rozmej@gmail.com> * Apply suggestion from @LukaszRozmej Co-authored-by: Lukasz Rozmej <lukasz.rozmej@gmail.com> * Update StartingSyncPivotUpdater.cs --------- Co-authored-by: Lukasz Rozmej <lukasz.rozmej@gmail.com>
diff --git a/src/Nethermind/Nethermind.Merge.Plugin/Synchronization/StartingSyncPivotUpdater.cs b/src/Nethermind/Nethermind.Merge.Plugin/Synchronization/StartingSyncPivotUpdater.cs
@@ -9,6 +9,7 @@
 using Nethermind.Consensus.Validators;
 using Nethermind.Core;
 using Nethermind.Core.Crypto;
+using Nethermind.Core.Extensions;
 using Nethermind.Logging;
 using Nethermind.Merge.Plugin.Handlers;
 using Nethermind.State.Snap;
@@ -18,7 +19,7 @@
 
 namespace Nethermind.Merge.Plugin.Synchronization;
 
-public class StartingSyncPivotUpdater
+public class StartingSyncPivotUpdater : IDisposable
 {
     private const string Pivot = "pivot";
     private readonly IBlockTree _blockTree;
@@ -29,7 +30,7 @@ public class StartingSyncPivotUpdater
     protected readonly IBeaconSyncStrategy _beaconSyncStrategy;
     protected readonly ILogger _logger;
 
-    private readonly CancellationTokenSource _cancellation = new();
+    private CancellationTokenSource? _cancellation = new();
 
     private static int _maxAttempts;
     private int _attemptsLeft;
@@ -69,7 +70,7 @@ private async void OnSyncModeChanged(object? sender, SyncModeChangedEventArgs sy
     {
         if ((syncMode.Current & SyncMode.UpdatingPivot) != 0 && Interlocked.CompareExchange(ref _updateInProgress, 1, 0) == 0)
         {
-            if (await TrySetFreshPivot(_cancellation.Token))
+            if (await TrySetFreshPivot(_cancellation!.Token))
             {
                 _syncModeSelector.Changed -= OnSyncModeChanged;
             }
@@ -236,4 +237,10 @@ protected void UpdateAndPrintPotentialNewPivot(Hash256 finalizedBlockHash)
             _alreadyAnnouncedNewPivotHash = finalizedBlockHash;
         }
     }
+
+    public void Dispose()
+    {
+        _syncModeSelector.Changed -= OnSyncModeChanged;
+        CancellationTokenExtensions.CancelDisposeAndClear(ref _cancellation);
+    }
 }

Original file line number	Diff line number	Diff line change
`@@ -9,6 +9,7 @@`
`9`	`9`	`using Nethermind.Consensus.Validators;`
`10`	`10`	`using Nethermind.Core;`
`11`	`11`	`using Nethermind.Core.Crypto;`
	`12`	`+using Nethermind.Core.Extensions;`
`12`	`13`	`using Nethermind.Logging;`
`13`	`14`	`using Nethermind.Merge.Plugin.Handlers;`
`14`	`15`	`using Nethermind.State.Snap;`
`@@ -18,7 +19,7 @@`
`18`	`19`
`19`	`20`	`namespace Nethermind.Merge.Plugin.Synchronization;`
`20`	`21`
`21`		`-public class StartingSyncPivotUpdater`
	`22`	`+public class StartingSyncPivotUpdater : IDisposable`
`22`	`23`	`{`
`23`	`24`	`private const string Pivot = "pivot";`
`24`	`25`	`private readonly IBlockTree _blockTree;`
`@@ -29,7 +30,7 @@ public class StartingSyncPivotUpdater`
`29`	`30`	`protected readonly IBeaconSyncStrategy _beaconSyncStrategy;`
`30`	`31`	`protected readonly ILogger _logger;`
`31`	`32`
`32`		`- private readonly CancellationTokenSource _cancellation = new();`
	`33`	`+ private CancellationTokenSource? _cancellation = new();`
`33`	`34`
`34`	`35`	`private static int _maxAttempts;`
`35`	`36`	`private int _attemptsLeft;`
`@@ -69,7 +70,7 @@ private async void OnSyncModeChanged(object? sender, SyncModeChangedEventArgs sy`
`69`	`70`	`{`
`70`	`71`	`if ((syncMode.Current & SyncMode.UpdatingPivot) != 0 && Interlocked.CompareExchange(ref _updateInProgress, 1, 0) == 0)`
`71`	`72`	`{`
`72`		`- if (await TrySetFreshPivot(_cancellation.Token))`
	`73`	`+ if (await TrySetFreshPivot(_cancellation!.Token))`
`73`	`74`	`{`
`74`	`75`	`_syncModeSelector.Changed -= OnSyncModeChanged;`
`75`	`76`	`}`
`@@ -236,4 +237,10 @@ protected void UpdateAndPrintPotentialNewPivot(Hash256 finalizedBlockHash)`
`236`	`237`	`_alreadyAnnouncedNewPivotHash = finalizedBlockHash;`
`237`	`238`	`}`
`238`	`239`	`}`
	`240`	`+`
	`241`	`+ public void Dispose()`
	`242`	`+ {`
	`243`	`+ _syncModeSelector.Changed -= OnSyncModeChanged;`
	`244`	`+ CancellationTokenExtensions.CancelDisposeAndClear(ref _cancellation);`
	`245`	`+ }`
`239`	`246`	`}`