Re: [ros-dev] [ros-diffs] [fireball] 34047: - Extend SEH to cover writing result to output arguments. Noticed by Stefan Ginsberg.

[Alex Ionescu]

Do you even realize the consequences of running the entire Object  
Manager code paths, the parse routine, and the other ~2500 lines of  
code associated with these APIs under SEH?

I'd guess not.

On 22-Jun-08, at 9:24 AM, fireball(a)svn.reactos.org wrote:

>   Author: fireball
>  Date: Sun Jun 22 11:24:15 2008
>  New Revision: 34047
>
>  URL: http://svn.reactos.org/svn/reactos?rev=34047&view=rev
>  Log:
>  - Extend SEH to cover writing result to output arguments. Noticed by  
>  Stefan Ginsberg.
>
>  Modified:
>     trunk/reactos/ntoskrnl/config/ntapi.c
>
>  Modified: trunk/reactos/ntoskrnl/config/ntapi.c
>  URL:
> http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/config/ntapi.c?re…
>  = 
>  = 
>  = 
>  = 
>  = 
>  = 
>  = 
>  = 
>  ======================================================================
>  --- trunk/reactos/ntoskrnl/config/ntapi.c [iso-8859-1] (original)
>  +++ trunk/reactos/ntoskrnl/config/ntapi.c [iso-8859-1] Sun Jun 22  
>  11:24:15 2008
>  @@ -63,6 +63,23 @@
>              /* Save the class directly */
>              if (Class) ParseContext.Class = *Class;
>          }
>  +
>  +        /* Setup the parse context */
>  +        ParseContext.CreateOperation = TRUE;
>  +        ParseContext.CreateOptions = CreateOptions;
>  +
>  +        /* Do the create */
>  +        Status = ObOpenObjectByName(ObjectAttributes,
>  +                                    CmpKeyObjectType,
>  +                                    PreviousMode,
>  +                                    NULL,
>  +                                    DesiredAccess,
>  +                                    &ParseContext,
>  +                                    &Handle);
>  +        if (NT_SUCCESS(Status)) *KeyHandle = Handle;
>  +
>  +        /* Return data to user */
>  +        if (Disposition) *Disposition = ParseContext.Disposition;
>      }
>      _SEH_HANDLE
>      {
>  @@ -70,24 +87,8 @@
>          Status = _SEH_GetExceptionCode();
>      }
>      _SEH_END;
>  -    if (!NT_SUCCESS(Status)) return Status;
>  -
>  -    /* Setup the parse context */
>  -    ParseContext.CreateOperation = TRUE;
>  -    ParseContext.CreateOptions = CreateOptions;
>  -
>  -    /* Do the create */
>  -    Status = ObOpenObjectByName(ObjectAttributes,
>  -                                CmpKeyObjectType,
>  -                                PreviousMode,
>  -                                NULL,
>  -                                DesiredAccess,
>  -                                &ParseContext,
>  -                                &Handle);
>  -    if (NT_SUCCESS(Status)) *KeyHandle = Handle;
>  -
>  -    /* Return data to user */
>  -    if (Disposition) *Disposition = ParseContext.Disposition;
>  +
>  +    /* Return status */
>      return Status;
>  }
>
>  @@ -109,14 +110,24 @@
>      {
>          /* Check for user-mode caller */
>          if (PreviousMode == UserMode)
>  -        {
>  +        {
>              /* Probe the key handle */
>              ProbeForWriteHandle(KeyHandle);
>              *KeyHandle = NULL;
>  -
>  +
>              /* Probe object attributes */
>              ProbeForRead(ObjectAttributes,  
>  sizeof(OBJECT_ATTRIBUTES), 4);
>          }
>  +
>  +        /* Just let the object manager handle this */
>  +        Status = ObOpenObjectByName(ObjectAttributes,
>  +                                    CmpKeyObjectType,
>  +                                    ExGetPreviousMode(),
>  +                                    NULL,
>  +                                    DesiredAccess,
>  +                                    &ParseContext,
>  +                                    &Handle);
>  +        if (NT_SUCCESS(Status)) *KeyHandle = Handle;
>      }
>      _SEH_HANDLE
>      {
>  @@ -124,18 +135,7 @@
>          Status = _SEH_GetExceptionCode();
>      }
>      _SEH_END;
>  -    if (!NT_SUCCESS(Status)) return Status;
>  -
>  -    /* Just let the object manager handle this */
>  -    Status = ObOpenObjectByName(ObjectAttributes,
>  -                                CmpKeyObjectType,
>  -                                ExGetPreviousMode(),
>  -                                NULL,
>  -                                DesiredAccess,
>  -                                &ParseContext,
>  -                                &Handle);
>  -    if (NT_SUCCESS(Status)) *KeyHandle = Handle;
>  -
>  +
>      /* Return status */
>      return Status;
>  }
>  
Best regards,
Alex Ionescu