[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 at 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?rev=34047&r1=34046&r2=34047&view=diff
> = 
> = 
> = 
> = 
> = 
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> = 
> ======================================================================
> --- 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