Changeset 40201 in vbox

Timestamp:

Feb 21, 2012 2:44:43 PM (13 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

76366

Message:

Main/VirtualBox: fix race due to insufficient synchronization

File:

• trunk/src/VBox/Main/src-server/VirtualBoxImpl.cpp (modified) (3 diffs)

trunk/src/VBox/Main/src-server/VirtualBoxImpl.cpp

@@ -5 +5 @@
 
 /*
- * Copyright (C) 2006-2011 Oracle Corporation
+ * Copyright (C) 2006-2012 Oracle Corporation
  *
  * This file is part of VirtualBox Open Source Edition (OSE), as
@@ -1674 +1674 @@
     ComObjPtr<Medium> pMedium;
 
-    /* we don't access non-const data members so no need to lock */
+    // have to get write lock as the whole find/update sequence must be done
+    // in one critical section, otherwise there are races which can lead to
+    // multiple Medium objects with the same content
+    AutoWriteLock treeLock(getMediaTreeLockHandle() COMMA_LOCKVAL_SRC_POS);
 
     // check if the device type is correct, and see if a medium for the
@@ -1716 +1719 @@
         if (SUCCEEDED(rc))
         {
-            AutoWriteLock treeLock(getMediaTreeLockHandle() COMMA_LOCKVAL_SRC_POS);
-
             switch (deviceType)
             {