[cgutman] 54534: [NTOSKRNL] - Fix a potential infinite loop in MmTrimUserMemory if we can't page out enough pages to meet the balancer's target

Author: cgutman
Date: Tue Nov 29 08:13:56 2011
New Revision: 54534

URL: http://svn.reactos.org/svn/reactos?rev=54534&view=rev
Log:
[NTOSKRNL]
- Fix a potential infinite loop in MmTrimUserMemory if we can't page out enough pages to meet the balancer's target

Modified:
    trunk/reactos/ntoskrnl/mm/balance.c

Modified: trunk/reactos/ntoskrnl/mm/balance.c
URL: http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/mm/balance.c?rev=5...
==============================================================================
--- trunk/reactos/ntoskrnl/mm/balance.c [iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/mm/balance.c [iso-8859-1] Tue Nov 29 08:13:56 2011
@@ -164,14 +164,12 @@
     PFN_NUMBER CurrentPage;
     PFN_NUMBER NextPage;
     NTSTATUS Status;
-    
+
     (*NrFreedPages) = 0;
-    
+
     CurrentPage = MmGetLRUFirstUserPage();
     while (CurrentPage != 0 && Target > 0)
     {
-        NextPage = MmGetLRUNextUserPage(CurrentPage);
-        
         Status = MmPageOutPhysicalAddress(CurrentPage);
         if (NT_SUCCESS(Status))
         {
@@ -179,10 +177,17 @@
             Target--;
             (*NrFreedPages)++;
         }
-        
+
+        NextPage = MmGetLRUNextUserPage(CurrentPage);
+        if (NextPage <= CurrentPage)
+        {
+            /* We wrapped around, so we're done */
+            break;
+        }
         CurrentPage = NextPage;
     }
-    return(STATUS_SUCCESS);
+
+    return STATUS_SUCCESS;
 }

VOID