Bug 1044408: enable crashing all GMP plugins on a pref strobe r=cpearce,ted

content/media/gmp/GMPChild.cpp

@@ -271,5 +271,12 @@ GMPChild::RecvPGMPDecryptorConstructor(PGMPDecryptorChild* aActor)
   return true;
 }
 
+bool
+GMPChild::RecvCrashPluginNow()
+{
+  abort();
+  return true;
+}
+
 } // namespace gmp
 } // namespace mozilla

content/media/gmp/GMPChild.h

@@ -47,6 +47,8 @@ private:
   virtual bool DeallocPGMPDecryptorChild(PGMPDecryptorChild* aActor) MOZ_OVERRIDE;
   virtual bool RecvPGMPDecryptorConstructor(PGMPDecryptorChild* aActor) MOZ_OVERRIDE;
 
+  virtual bool RecvCrashPluginNow() MOZ_OVERRIDE;
+
   virtual void ActorDestroy(ActorDestroyReason aWhy) MOZ_OVERRIDE;
   virtual void ProcessingError(Result aWhat) MOZ_OVERRIDE;
 

content/media/gmp/GMPParent.cpp

@@ -101,6 +101,14 @@ GMPParent::Init(GeckoMediaPluginService *aService, nsIFile* aPluginDir)
   return ReadGMPMetaData();
 }
 
+void
+GMPParent::Crash()
+{
+  if (mState != GMPStateNotLoaded) {
+    unused << SendCrashPluginNow();
+  }
+}
+
 nsresult
 GMPParent::LoadProcess()
 {

content/media/gmp/GMPParent.h

@@ -62,6 +62,8 @@ public:
   nsresult Init(GeckoMediaPluginService *aService, nsIFile* aPluginDir);
   nsresult CloneFrom(const GMPParent* aOther);
 
+  void Crash();
+
   nsresult LoadProcess();
 
   // Called internally to close this if we don't need it

content/media/gmp/GMPService.cpp

@@ -9,6 +9,7 @@
 #include "GMPVideoDecoderParent.h"
 #include "nsIObserverService.h"
 #include "GeckoChildProcessHost.h"
+#include "mozilla/Preferences.h"
 #include "mozilla/ClearOnShutdown.h"
 #include "mozilla/SyncRunnable.h"
 #include "nsXPCOMPrivate.h"
@@ -145,6 +146,11 @@ GeckoMediaPluginService::Init()
   MOZ_ALWAYS_TRUE(NS_SUCCEEDED(obsService->AddObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID, false)));
   MOZ_ALWAYS_TRUE(NS_SUCCEEDED(obsService->AddObserver(this, NS_XPCOM_SHUTDOWN_THREADS_OBSERVER_ID, false)));
 
+  nsCOMPtr<nsIPrefBranch> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);
+  if (prefs) {
+    prefs->AddObserver("media.gmp.plugin.crash", this, false);
+  }
+
   // Kick off scanning for plugins
   nsCOMPtr<nsIThread> thread;
   unused << GetThread(getter_AddRefs(thread));
@@ -155,7 +161,26 @@ GeckoMediaPluginService::Observe(nsISupports* aSubject,
                                  const char* aTopic,
                                  const char16_t* aSomeData)
 {
-  if (!strcmp(NS_XPCOM_SHUTDOWN_OBSERVER_ID, aTopic)) {
+  if (!strcmp(aTopic, NS_PREFBRANCH_PREFCHANGE_TOPIC_ID)) {
+    nsCOMPtr<nsIPrefBranch> branch( do_QueryInterface(aSubject) );
+    if (branch) {
+      bool crashNow = false;
+      if (NS_LITERAL_STRING("media.gmp.plugin.crash").Equals(aSomeData)) {
+        branch->GetBoolPref("media.gmp.plugin.crash",  &crashNow);
+      }
+      if (crashNow) {
+        nsCOMPtr<nsIThread> gmpThread;
+        {
+          MutexAutoLock lock(mMutex);
+          gmpThread = mGMPThread;
+        }
+        if (gmpThread) {
+          gmpThread->Dispatch(WrapRunnable(this, &GeckoMediaPluginService::CrashPlugins),
+                              NS_DISPATCH_NORMAL);
+        }
+      }
+    }
+  } else if (!strcmp(NS_XPCOM_SHUTDOWN_OBSERVER_ID, aTopic)) {
     nsCOMPtr<nsIThread> gmpThread;
     {
       MutexAutoLock lock(mMutex);
@@ -340,6 +365,17 @@ GeckoMediaPluginService::UnloadPlugins()
   mPlugins.Clear();
 }
 
+void
+GeckoMediaPluginService::CrashPlugins()
+{
+  MOZ_ASSERT(NS_GetCurrentThread() == mGMPThread);
+
+  MutexAutoLock lock(mMutex);
+  for (uint32_t i = 0; i < mPlugins.Length(); i++) {
+    mPlugins[i]->Crash();
+  }
+}
+
 void
 GeckoMediaPluginService::LoadFromEnvironment()
 {

content/media/gmp/GMPService.h

@@ -44,6 +44,7 @@ private:
                                 const nsTArray<nsCString>& aTags);
 
   void UnloadPlugins();
+  void CrashPlugins();
 
   void LoadFromEnvironment();
   void ProcessPossiblePlugin(nsIFile* aDir);

content/media/gmp/PGMP.ipdl

@@ -27,6 +27,8 @@ child:
   async PGMPDecryptor();
   async PGMPVideoDecoder();
   async PGMPVideoEncoder();
+
+  async CrashPluginNow();
 };
 
 } // namespace gmp