corysanin/tubestation
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Bug 1788532 - Block dynamic module load processing during sync XHR r=smaug

Browse Source 
The problem is that synchronous XMLHttpRequest requests can spin the event loop
and cause us to process dynamic module loads (by calling
JS::FinishDynamicModuleImport) when we are already inside JS::ModuleEvaluate.
The module algorithms assume that they are not reentrant.

The patch changes dyammic module load processing to happen in the same way as
async script loads (of both classic scripts and modules), which are blocked
during sync XHR by Document::SuppressEventHandling calling
ScriptLoader::AddExecuteBlocker.

Differential Revision: https://phabricator.services.mozilla.com/D157218
This commit is contained in:
Jon Coppeard
2022-09-15 09:14:11 +00:00
parent 481fc2aee2
commit b33e676c20
3 changed files with 17 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

21
dom/script/ScriptLoader.cpp
View File

@@ -495,15 +495,7 @@ class ScriptRequestProcessor : public Runnable {
: Runnable("dom::ScriptRequestProcessor"),
mLoader(aLoader),
mRequest(aRequest) {}
NS_IMETHOD Run() override {
if (mRequest->IsModuleRequest() &&
mRequest->AsModuleRequest()->IsDynamicImport()) {
mRequest->AsModuleRequest()->ProcessDynamicImport();
return NS_OK;
}
return mLoader->ProcessRequest(mRequest);
}
NS_IMETHOD Run() override { return mLoader->ProcessRequest(mRequest); }
};
void ScriptLoader::RunScriptWhenSafe(ScriptLoadRequest* aRequest) {
@@ -1792,6 +1784,11 @@ nsresult ScriptLoader::ProcessRequest(ScriptLoadRequest* aRequest) {
if (aRequest->IsModuleRequest()) {
ModuleLoadRequest* request = aRequest->AsModuleRequest();
if (request->IsDynamicImport()) {
request->ProcessDynamicImport();
return NS_OK;
}
if (request->mModuleScript) {
if (!request->InstantiateModuleGraph()) {
request->mModuleScript = nullptr;
@@ -3629,6 +3626,7 @@ void ScriptLoader::AddAsyncRequest(ScriptLoadRequest* aRequest) {
void ScriptLoader::MaybeMoveToLoadedList(ScriptLoadRequest* aRequest) {
MOZ_ASSERT(aRequest->IsReadyToRun());
MOZ_ASSERT(aRequest->IsTopLevel());
// If it's async, move it to the loaded list.
// aRequest->GetScriptLoadContext()->mInAsyncList really _should_ be in a
@@ -3640,6 +3638,11 @@ void ScriptLoader::MaybeMoveToLoadedList(ScriptLoadRequest* aRequest) {
RefPtr<ScriptLoadRequest> req = mLoadingAsyncRequests.Steal(aRequest);
mLoadedAsyncRequests.AppendElement(req);
}
} else if (aRequest->IsModuleRequest() &&
aRequest->AsModuleRequest()->IsDynamicImport()) {
// Process dynamic imports with async scripts.
MOZ_ASSERT(!aRequest->isInList());
mLoadedAsyncRequests.AppendElement(aRequest);
}
}