Changeset 77506 in vbox for trunk/src/VBox/Main/src-server

Timestamp:

Feb 28, 2019 4:25:19 PM (6 years ago)

Author:

vboxsync

Message:

Main/HostDnsService: fix a use-after-free running VBoxSVC in debug mode.
bugref:9144: AddressSanitizer: heap-use-after-free in VBoxSVC in HostDnsMonitor::pollGlobalExtraData()
This did not trigger during normal usage, but when debugging and keeping
VBoxSVC around it did. The change terminates the Host DNS monitor thread
properly when the VirtualBox object is destroyed, which in normal use also
ends the process.

Location:

trunk/src/VBox/Main/src-server

Files:

• HostDnsService.cpp (modified) (4 diffs)
• HostDnsService.h (modified) (2 diffs)
• HostImpl.cpp (modified) (1 diff)

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

@@ -154 +154 @@
 void HostDnsMonitor::shutdown()
 {
-    /** @todo never called.
-     * HostDnsMonitor should be referenced by HostDnsMonitorProxy objects and the Host object
-     * and automatically deleted when not referenced anymore.
-     * Currently HostDnsMonitor can use already deleted m->virtualbox.
-     */
+    monitorThreadShutdown();
+    int rc = RTThreadWait(m->hMonitoringThread, 5000, NULL);
+    AssertRCSuccess(rc);
 }
 
@@ -179 +177 @@
         rc = RTThreadCreate(&m->hMonitoringThread,
                             HostDnsMonitor::threadMonitoringRoutine,
-                            this, 128 * _1K, RTTHREADTYPE_IO, 0, "dns-monitor");
+                            this, 128 * _1K, RTTHREADTYPE_IO,
+                            RTTHREADFLAGS_WAITABLE, "dns-monitor");
         AssertRCReturn(rc, E_FAIL);
 
@@ -267 +266 @@
 HostDnsMonitorProxy::~HostDnsMonitorProxy()
 {
-    if (m)
-    {
-        /* XXX: m->monitor */
-        delete m;
-        m = NULL;
-    }
+    Assert(!m);
 }
 
@@ -282 +276 @@
 }
 
+
+void HostDnsMonitorProxy::uninit()
+{
+    m->monitor->shutdown();
+    delete m;
+    m = NULL;
+}
 
 void HostDnsMonitorProxy::notify(const HostDnsInformation &info)

trunk/src/VBox/Main/src-server/HostDnsService.h

@@ -58 +58 @@
   public:
     static HostDnsMonitor *createHostDnsMonitor();
-    static void shutdown();
+    void shutdown();
 
     /* @note: method will wait till client call
@@ -95 +95 @@
     ~HostDnsMonitorProxy();
     void init(VirtualBox *virtualbox);
+    void uninit();
     void notify(const HostDnsInformation &info);
 

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

@@ -498 +498 @@
         m->llNetIfs.pop_front();
     }
+
+    m->hostDnsMonitorProxy.uninit();
 
 #ifdef VBOX_WITH_USB