Changeset 8809 for trunk/src/kernel32/virtual.cpp

Timestamp:

Jun 30, 2002, 3:46:46 PM (23 years ago)

Author:

sandervl

Message:

VirtualFree; don't allow app to decommit stack pages (VAC runtime uses last stack page to store some internal data; if freed pe/pec will crash during exit)

File:

• trunk/src/kernel32/virtual.cpp (modified) (3 diffs)

trunk/src/kernel32/virtual.cpp

@@ -1 @@
-/* $Id: virtual.cpp,v 1.44 2002-05-20 13:48:50 sandervl Exp $ */
+/* $Id: virtual.cpp,v 1.45 2002-06-30 13:46:46 sandervl Exp $ */
 
 /*
@@ -23 +23 @@
 #include <string.h>
 #include <win\virtual.h>
+#include <win\thread.h>
 #include <heapstring.h>
 #include <handlemanager.h>
@@ -446 +447 @@
                           DWORD  FreeType)
 {
-  DWORD rc;
-
-  SetLastError(ERROR_SUCCESS);
-
-  // verify parameters
-  if ( (FreeType & MEM_RELEASE) && (cbSize   != 0) )
-  {
-    dprintf(("WARNING: VirtualFree: invalid parameter!!"));
-    SetLastError(ERROR_INVALID_PARAMETER);
-    return(FALSE);
-  }
-
-  if ( (FreeType & MEM_DECOMMIT) &&
-       (FreeType & MEM_RELEASE) )
-  {
-    dprintf(("WARNING: VirtualFree: invalid parameter!!"));
-    SetLastError(ERROR_INVALID_PARAMETER);
-    return(FALSE);
-  }
-
-  // decommit memory
-  if (FreeType &  MEM_DECOMMIT)
-  {
-    // decommit memory block
-    rc = OSLibDosSetMem(lpvAddress, cbSize, PAG_DECOMMIT);
-    if(rc)
-    {
-    if(rc == 32803) { //SvL: ERROR_ALIAS
-            dprintf(("KERNEL32:VirtualFree:OsLibSetMem rc = #%d; app tries to decommit aliased memory; ignore", rc));
-        return(TRUE);
-    }
-        dprintf(("KERNEL32:VirtualFree:OsLibSetMem rc = #%d\n", rc));
-        SetLastError(ERROR_INVALID_ADDRESS);
-    return(FALSE);
-    }
-  }
-
-  // release memory
-  if (FreeType &  MEM_RELEASE)
-  {
-    rc = OSLibDosFreeMem(lpvAddress); // free the memory block
-    if(rc)
-    {
-      dprintf(("KERNEL32:VirtualFree:OsLibFreeMem rc = #%d\n",
-               rc));
-      SetLastError(ERROR_INVALID_ADDRESS);
-      return(FALSE);
-    }
-  }
-
-  return(TRUE);
+    DWORD rc;
+
+    SetLastError(ERROR_SUCCESS);
+
+    // verify parameters
+    if((FreeType & MEM_RELEASE) && (cbSize != 0))
+    {
+        dprintf(("WARNING: VirtualFree: invalid parameter!!"));
+        SetLastError(ERROR_INVALID_PARAMETER);
+        return(FALSE);
+    }
+
+    if((FreeType & MEM_DECOMMIT) && (FreeType & MEM_RELEASE))
+    {
+        dprintf(("WARNING: VirtualFree: invalid parameter!!"));
+        SetLastError(ERROR_INVALID_PARAMETER);
+        return(FALSE);
+    }
+
+    // decommit memory
+    if (FreeType &  MEM_DECOMMIT)
+    {
+        // check if app wants to decommit stack pages -> don't allow that!
+        TEB *teb = GetThreadTEB();
+        if(teb) {
+            if(lpvAddress >= teb->stack_low && lpvAddress < teb->stack_top) {
+                //pretend we did was was asked
+                dprintf(("WARNING: app tried to decommit stack pages; pretend success"));
+                return TRUE;
+            }
+        }
+        // decommit memory block
+        rc = OSLibDosSetMem(lpvAddress, cbSize, PAG_DECOMMIT);
+        if(rc)
+        {
+            if(rc == 32803) { //SvL: ERROR_ALIAS
+                dprintf(("KERNEL32:VirtualFree:OsLibSetMem rc = #%d; app tries to decommit aliased memory; ignore", rc));
+                return(TRUE);
+            }
+            dprintf(("KERNEL32:VirtualFree:OsLibSetMem rc = #%d\n", rc));
+            SetLastError(ERROR_INVALID_ADDRESS);
+            return(FALSE);
+        }
+    }
+
+    // release memory
+    if (FreeType &  MEM_RELEASE)
+    {
+        rc = OSLibDosFreeMem(lpvAddress); // free the memory block
+        if(rc)
+        {
+            dprintf(("KERNEL32:VirtualFree:OsLibFreeMem rc = #%d\n", rc));
+            SetLastError(ERROR_INVALID_ADDRESS);
+            return(FALSE);
+        }
+    }
+    return TRUE;
 }
 //******************************************************************************