Piotr Caban : ntdll: Restore stack guard and prevent stack from shrinking.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 6b2c9505c6a84f53798aa9509ef75bb4e1b86d56
URL:    http://source.winehq.org/git/wine.git/?a=commit;h=6b2c9505c6a84f53798aa9509ef75bb4e1b86d56

Author: Piotr Caban <piotr at codeweavers.com>
Date:   Tue Apr 12 15:10:05 2011 +0200

ntdll: Restore stack guard and prevent stack from shrinking.

---

 dlls/ntdll/virtual.c |    8 ++++++--
 1 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/dlls/ntdll/virtual.c b/dlls/ntdll/virtual.c
index 0913b71..d88b734 100644
--- a/dlls/ntdll/virtual.c
+++ b/dlls/ntdll/virtual.c
@@ -1618,8 +1618,12 @@ BOOL virtual_handle_stack_fault( void *addr )
         if (vprot & VPROT_GUARD)
         {
             VIRTUAL_SetProt( view, page, page_size, vprot & ~VPROT_GUARD );
-            if ((char *)page + page_size == NtCurrentTeb()->Tib.StackLimit)
-                NtCurrentTeb()->Tib.StackLimit = page;
+            NtCurrentTeb()->Tib.StackLimit = page;
+            if ((char *)page >= (char *)NtCurrentTeb()->DeallocationStack + 2*page_size)
+            {
+                vprot = view->prot[((char *)page - page_size - (char *)view->base) >> page_shift];
+                VIRTUAL_SetProt( view, (char *)page - page_size, page_size, vprot | VPROT_GUARD );
+            }
             ret = TRUE;
         }
     }