From: John Wolfe <jwolfe@vmware.com>
Date: Tue, 22 Sep 2020 21:54:05 +0000 (-0700)
Subject: hgfsServerOplockMonitor.c  HgfsOplockUnmonitorFileChange():
X-Git-Tag: stable-11.3.0~326
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=bc811a0fcd6b80082fc7f513928e9c448e7bf46b;p=thirdparty%2Fopen-vm-tools.git

hgfsServerOplockMonitor.c  HgfsOplockUnmonitorFileChange():

There is no need to cancel the monitor action if the oplock monitor
module has already been destroyed.   Avoid a possible NULL pointer
dereference.
---

diff --git a/open-vm-tools/lib/hgfsServer/hgfsServerOplockMonitor.c b/open-vm-tools/lib/hgfsServer/hgfsServerOplockMonitor.c
index b19159b5c..1d97e5c45 100644
--- a/open-vm-tools/lib/hgfsServer/hgfsServerOplockMonitor.c
+++ b/open-vm-tools/lib/hgfsServer/hgfsServerOplockMonitor.c
@@ -434,6 +434,16 @@ HgfsOplockUnmonitorFileChangeInternal(HOM_HANDLE handle)             // IN:
 void
 HgfsOplockUnmonitorFileChange(HOM_HANDLE handle)             // IN:
 {
+   /*
+    * This function is a callback function and may be called at any time, even
+    * when the oplock monitor module is destroyed.
+    * So, check if the oplock monitor module is initialized.
+    */
+   if (!gOplockMonitorInit) {
+      Log("%s: OplockMonitor module is not inited\n", __FUNCTION__);
+      return;
+   }
+
    MXUser_AcquireExclLock(oplockMonitorLock);
    HgfsOplockUnmonitorFileChangeInternal(handle);
    MXUser_ReleaseExclLock(oplockMonitorLock);