[NTOS:IO]

- Fix potential null-pointer dereferencing (we call IopCleanupAfterException in IopDeviceFsIoControl with Irp == NULL)

svn path=/trunk/; revision=72548

reactos/ntoskrnl/io/iomgr/iofunc.c

@@ -22,26 +22,29 @@
 VOID
 NTAPI
 IopCleanupAfterException(IN PFILE_OBJECT FileObject,
-                         IN PIRP Irp,
+                         IN PIRP Irp OPTIONAL,
                          IN PKEVENT Event OPTIONAL,
                          IN PKEVENT LocalEvent OPTIONAL)
 {
     PAGED_CODE();
     IOTRACE(IO_API_DEBUG, "IRP: %p. FO: %p \n", Irp, FileObject);
 
-    /* Check if we had a buffer */
-    if (Irp->AssociatedIrp.SystemBuffer)
+    if (Irp)
     {
-        /* Free it */
-        ExFreePool(Irp->AssociatedIrp.SystemBuffer);
+        /* Check if we had a buffer */
+        if (Irp->AssociatedIrp.SystemBuffer)
+        {
+            /* Free it */
+            ExFreePool(Irp->AssociatedIrp.SystemBuffer);
+        }
+
+        /* Free the mdl */
+        if (Irp->MdlAddress) IoFreeMdl(Irp->MdlAddress);
+
+        /* Free the IRP */
+        IoFreeIrp(Irp);
     }
 
-    /* Free the mdl */
-    if (Irp->MdlAddress) IoFreeMdl(Irp->MdlAddress);
-
-    /* Free the IRP */
-    IoFreeIrp(Irp);
-
     /* Check if we had a file lock */
     if (FileObject->Flags & FO_SYNCHRONOUS_IO)
     {