[ros-diffs] [cgutman] 54569: [NTOSKRNL] - Use SEH when copying values back to the caller from NtFreeVirtualMemory

[cgutman]

Author: cgutman
Date: Sat Dec  3 11:18:18 2011
New Revision: 54569

URL: http://svn.reactos.org/svn/reactos?rev=54569&view=rev
Log:
[NTOSKRNL]
- Use SEH when copying values back to the caller from NtFreeVirtualMemory

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=54569&r1=54568&r2=54569&view=diff
==============================================================================
--- trunk/reactos/ntoskrnl/mm/anonmem.c [iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/mm/anonmem.c [iso-8859-1] Sat Dec  3 11:18:18 2011
@@ -1033,11 +1033,11 @@
         /* Check for user-mode parameters */
         if (PreviousMode != KernelMode)
         {
-            /* Make sure they are writable */
-            ProbeForWritePointer(UBaseAddress);
-            ProbeForWriteUlong(URegionSize);
-        }
-        
+            /* Make sure they are readable */
+            ProbeForReadPointer(UBaseAddress);
+            ProbeForReadUlong(URegionSize);
+        }
+
         /* Capture their values */
         PBaseAddress = *UBaseAddress;
         PRegionSize = *URegionSize;
@@ -1183,9 +1183,27 @@
         goto unlock_deref_and_return;
     }
 
-    /* Copy rounded values back in success case */
-    *UBaseAddress = BaseAddress;
-    *URegionSize = RegionSize;
+    /* Enter SEH */
+    _SEH2_TRY
+    {
+        /* Check for user-mode parameters */
+        if (PreviousMode != KernelMode)
+        {
+            /* Make sure they are writable */
+            ProbeForWritePointer(UBaseAddress);
+            ProbeForWriteUlong(URegionSize);
+        }
+
+        /* Copy rounded values back in success case */
+        *UBaseAddress = BaseAddress;
+        *URegionSize = RegionSize;
+    }
+    _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
+    {
+        Status = _SEH2_GetExceptionCode();
+        DPRINT1("Failed to copy values back! (Status: 0x%x)\n", Status);
+    }
+    _SEH2_END;
 
 unlock_deref_and_return:
     MmUnlockAddressSpace(AddressSpace);