Merge 132848 - IndexedDB: Crash on checking version of corrupt backing store

Source/WebCore/Modules/indexeddb/IDBLevelDBBackingStore.cpp

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 277 matching lines @@
     } else {
         if (!makeAllDirectories(pathBase)) {
             LOG_ERROR("Unable to create IndexedDB database path %s", pathBase.utf8().data());
             HistogramSupport::histogramEnumeration("WebCore.IndexedDB.BackingStore.OpenStatus", IDBLevelDBBackingStoreOpenFailedDirectory, IDBLevelDBBackingStoreOpenMax);
             return PassRefPtr<IDBBackingStore>();
         }
 
         String path = pathByAppendingComponent(pathBase, securityOrigin->databaseIdentifier() + ".indexeddb.leveldb");
 
         db = LevelDBDatabase::open(path, comparator.get());
-        bool knownSchema = isSchemaKnown(db.get());
-        if (!knownSchema) {
+        if (db && !isSchemaKnown(db.get())) {
             LOG_ERROR("IndexedDB backing store had unknown schema, treating it as failure to open");
             HistogramSupport::histogramEnumeration("WebCore.IndexedDB.BackingStore.OpenStatus", IDBLevelDBBackingStoreOpenFailedUnknownSchema, IDBLevelDBBackingStoreOpenMax);
+            db.release();
         }
 
-        if (db && knownSchema)
+        if (db)
             HistogramSupport::histogramEnumeration("WebCore.IndexedDB.BackingStore.OpenStatus", IDBLevelDBBackingStoreOpenSuccess, IDBLevelDBBackingStoreOpenMax);
         else {
             LOG_ERROR("IndexedDB backing store open failed, attempting cleanup");
             bool success = LevelDBDatabase::destroy(path);
             if (!success) {
                 LOG_ERROR("IndexedDB backing store cleanup failed");
                 HistogramSupport::histogramEnumeration("WebCore.IndexedDB.BackingStore.OpenStatus", IDBLevelDBBackingStoreOpenCleanupDestroyFailed, IDBLevelDBBackingStoreOpenMax);
                 return PassRefPtr<IDBBackingStore>();
             }
 
@@ skipping 1584 matching lines @@
     String path = pathByAppendingComponent(pathBase, securityOrigin->databaseIdentifier() + ".indexeddb.leveldb");
 
     // FIXME: this is checking for presence of the domain, not the database itself
     return fileExists(path+"/CURRENT");
 }
 
 } // namespace WebCore
 
 #endif // USE(LEVELDB)
 #endif // ENABLE(INDEXED_DATABASE)