diff --git a/content/media/plugins/MediaPluginHost.cpp b/content/media/plugins/MediaPluginHost.cpp
index 9b85e1f7d52..f211ffb616f 100644
--- a/content/media/plugins/MediaPluginHost.cpp
+++ b/content/media/plugins/MediaPluginHost.cpp
@@ -273,15 +273,16 @@ bool MediaPluginHost::FindDecoder(const nsACString& aMimeType, const char* const
 
 MPAPI::Decoder *MediaPluginHost::CreateDecoder(MediaResource *aResource, const nsACString& aMimeType)
 {
-  const char *chars;
-  size_t len = NS_CStringGetData(aMimeType, &chars, nullptr);
+  NS_ENSURE_TRUE(aResource, nullptr);
 
-  Decoder *decoder = new Decoder();
+  nsAutoPtr<Decoder> decoder(new Decoder());
   if (!decoder) {
     return nullptr;
   }
   decoder->mResource = aResource;
 
+  const char *chars;
+  size_t len = NS_CStringGetData(aMimeType, &chars, nullptr);
   for (size_t n = 0; n < mPlugins.Length(); ++n) {
     Manifest *plugin = mPlugins[n];
     const char* const *codecs;
@@ -289,7 +290,8 @@ MPAPI::Decoder *MediaPluginHost::CreateDecoder(MediaResource *aResource, const n
       continue;
     }
     if (plugin->CreateDecoder(&sPluginHost, decoder, chars, len)) {
-      return decoder;
+      aResource->AddRef();
+      return decoder.forget();
     }
   }
 
@@ -299,6 +301,12 @@ MPAPI::Decoder *MediaPluginHost::CreateDecoder(MediaResource *aResource, const n
 void MediaPluginHost::DestroyDecoder(Decoder *aDecoder)
 {
   aDecoder->DestroyDecoder(aDecoder);
+  MediaResource* resource = GetResource(aDecoder);
+  if (resource) {
+    // resource *shouldn't* be null, but check anyway just in case the plugin
+    // decoder does something stupid.
+    resource->Release();
+  }
   delete aDecoder;
 }