WorkerCacheStorageConnection::doRemove can assert in case two frames …

…try to delete the same cache at the same time

https://bugs.webkit.org/show_bug.cgi?id=183041

Patch by Youenn Fablet <youenn@apple.com> on 2018-02-22
Reviewed by Chris Dumez.

* Modules/cache/WorkerCacheStorageConnection.cpp:
(WebCore::WorkerCacheStorageConnection::doRemove): Update the assertion to accept the
case of an already deleted cache, i.e. returned identifer is 0.

Canonical link: https://commits.webkit.org/198793@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@228924 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/WebCore/ChangeLog

@@ -1,3 +1,14 @@
+2018-02-22  Youenn Fablet  <youenn@apple.com>
+
+        WorkerCacheStorageConnection::doRemove can assert in case two frames try to delete the same cache at the same time
+        https://bugs.webkit.org/show_bug.cgi?id=183041
+
+        Reviewed by Chris Dumez.
+
+        * Modules/cache/WorkerCacheStorageConnection.cpp:
+        (WebCore::WorkerCacheStorageConnection::doRemove): Update the assertion to accept the
+        case of an already deleted cache, i.e. returned identifer is 0.
+
 2018-02-22  Alejandro G. Castro  <alex@igalia.com>
 
         Remove some code leftovers in LibWebRTCMediaEndpoint and RealtimeOutgoingVideoSource classes

Source/WebCore/Modules/cache/WorkerCacheStorageConnection.cpp

@@ -124,7 +124,7 @@ void WorkerCacheStorageConnection::doRemove(uint64_t requestIdentifier, uint64_t
 {
     callOnMainThread([workerThread = makeRef(m_scope.thread()), mainThreadConnection = m_mainThreadConnection, requestIdentifier, cacheIdentifier] () mutable {
         mainThreadConnection->remove(cacheIdentifier, [workerThread = WTFMove(workerThread), requestIdentifier, cacheIdentifier] (const CacheIdentifierOrError& result) mutable {
-            ASSERT_UNUSED(cacheIdentifier, !result.has_value() || result.value().identifier == cacheIdentifier);
+            ASSERT_UNUSED(cacheIdentifier, !result.has_value() || !result.value().identifier || result.value().identifier == cacheIdentifier);
             workerThread->runLoop().postTaskForMode([requestIdentifier, result] (auto& scope) mutable {
                 downcast<WorkerGlobalScope>(scope).cacheStorageConnection().removeCompleted(requestIdentifier, result);
             }, WorkerRunLoop::defaultMode());