[mjmartin] 40857: - MmProtectAnonMem: Search all Regions in Memory Area up to Length for MEM_COMMIT prior to altering memory protection. Fixes 6 kernel32_winetest for virtual memory.

Author: mjmartin
Date: Sat May  9 13:54:50 2009
New Revision: 40857

URL: http://svn.reactos.org/svn/reactos?rev=40857&view=rev
Log:
- MmProtectAnonMem: Search all Regions in Memory Area up to Length for MEM_COMMIT prior to altering memory protection. 
  Fixes 6 kernel32_winetest for virtual memory.

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

Modified: trunk/reactos/ntoskrnl/mm/anonmem.c
URL: http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/mm/anonmem.c?rev=4...
==============================================================================
--- trunk/reactos/ntoskrnl/mm/anonmem.c [iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/mm/anonmem.c [iso-8859-1] Sat May  9 13:54:50 2009
@@ -1034,26 +1034,48 @@
                  PULONG OldProtect)
 {
    PMM_REGION Region;
-   NTSTATUS Status;
-
-   Region = MmFindRegion(MemoryArea->StartingAddress,
-                         &MemoryArea->Data.VirtualMemoryData.RegionListHead,
-                         BaseAddress, NULL);
-   if (Region->Type == MEM_COMMIT)
-   {
-       /* FIXME: check if the whole range is committed 
-        * before altering the memory */
+   NTSTATUS Status = STATUS_SUCCESS;
+   ULONG LengthCount = 0;
+
+   /* Search all Regions in MemoryArea up to Length */
+   /* Every Region up to Length must be committed for success */
+   for (;;)
+   {
+      Region = MmFindRegion(MemoryArea->StartingAddress,
+                            &MemoryArea->Data.VirtualMemoryData.RegionListHead,
+                            (PVOID)((ULONG_PTR)BaseAddress + (ULONG_PTR)LengthCount), NULL);
+
+      /* If a Region was found and it is committed */
+      if ((Region) && (Region->Type == MEM_COMMIT))
+      {
+         LengthCount += Region->Length;
+         if (Length <= LengthCount) break;
+         continue;
+      }
+      /* If Region was found and it is not commited */
+      else if (Region)
+      {
+         Status = STATUS_NOT_COMMITTED;
+         break;
+      }
+      /* If no Region was found at all */
+      else if (LengthCount == 0)
+      {
+         Status = STATUS_INVALID_ADDRESS;
+         break;
+      }
+   }
+
+   if (NT_SUCCESS(Status))
+   {
        *OldProtect = Region->Protect;
        Status = MmAlterRegion(AddressSpace, MemoryArea->StartingAddress,
                               &MemoryArea->Data.VirtualMemoryData.RegionListHead,
                               BaseAddress, Length, Region->Type, Protect,
                               MmModifyAttributes);
    }
-   else
-   {
-       Status = STATUS_NOT_COMMITTED;
-   }
-   return(Status);
+
+   return (Status);
 }

NTSTATUS NTAPI