Re: Fixable

From: Alun Jones (alun@texis.com)
Date: 08/23/02


From: alun@texis.com (Alun Jones)
Date: Fri, 23 Aug 2002 16:02:54 GMT

In article <ak57s5$hcp$3@news1.xs4all.nl>, Casper H.S. Dik
<Casper.Dik@Sun.COM> wrote:
>>A better fix, that could be applied by an OS patch, would be to actually alter
>>the default window procedure, and the SetTimer / KillTimer functions, so that
>>a WM_TIMER message with a callback would only be accepted if the callback
>>address matched that passed in through a SetTimer call in the same process
>>space.
>
>Why not filter WM_TIMER messages when they're passed from one security
>context to a more privileged one?

Not much of a reason. But then again, why not prevent WM_TIMER messages from
containing a callback function pointer? SetTimer gives you a timer ID (or
takes one from you) - why have an ability to pass a function pointer to be
given back "later"?

Alun.
~~~~

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Relevant Pages

  • Re: Fixable
    ... >>the default window procedure, and the SetTimer / KillTimer functions, so that ... >>a WM_TIMER message with a callback would only be accepted if the callback ... >>address matched that passed in through a SetTimer call in the same process ... Fax/Voice +1258-9858 | read details of WFTPD Pro for XP/2000/NT. ...
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  • Re: Fixable
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