Re: Misc bugs found by using valgrind

[Shachar Shemesh]

Michael Günnewig wrote:
> Changelog:
>  Fixed use of uninitialized memory and wrong buffersize (found by valgrind).
>
> Michael
>
> ------------------------------------------------------------------------
>
> --- dlls/avifil32/api.c.SAV	2003-09-20 16:14:45.000000000 +0200
> +++ dlls/avifil32/api.c	2003-09-20 14:46:10.000000000 +0200
> @@ -1009,7 +1009,7 @@
>   szFilter[0] = 0;
>   szFilter[1] = 0;
>
> -  wszFilter = (LPWSTR)GlobalAllocPtr(GHND, cbFilter);
> +  wszFilter = (LPWSTR)GlobalAllocPtr(GHND, cbFilter * sizeof(WCHAR));
>   if (wszFilter == NULL)
>     return AVIERR_MEMORY;

What are we doing to prevent integer overflow on these allocations? 
Shouldn't we, perhaps, use some wrapper that checks that 
"cbFilter*sizeof(WCHAR)" is not greater than "MAXINT"?

             Shachar

-- 
Shachar Shemesh
Open Source integration consultant
Home page & resume - http://www.shemesh.biz/

Misc bugs found by using valgrind

Shachar Shemesh <wine-devel(a)shemesh.biz> writes:
> Michael Günnewig wrote:
> > Changelog:
> >  Fixed use of uninitialized memory and wrong buffersize (found by valgrind).
> > ...
> > What are we doing to prevent integer overflow on these allocations?
> > Shouldn't we, perhaps, use some wrapper that checks that
> > "cbFilter*sizeof(WCHAR)" is not greater than "MAXINT"?

It's a point, so here is the new patch.

  Michael

Misc bugs found by using valgrind

[Alexandre Julliard]

MichaelGuennewig(a)gmx.de (Michael Günnewig) writes:
> It's a point, so here is the new patch.

I don't think we need to check string sizes against MAXINT, that's
just a waste of time. Also please don't add memsets to fix valgrind
complaints, the bugs need to be fixed properly not just hidden by
clearing everything.

-- 
Alexandre Julliard
julliard(a)winehq.com

Misc bugs found by using valgrind

Alexandre Julliard <julliard(a)winehq.org> writes:
> MichaelGuennewig(a)gmx.de (Michael Günnewig) writes:
> > It's a point, so here is the new patch.
>
> I don't think we need to check string sizes against MAXINT, that's
> just a waste of time.

Okay you're correct, the check isn't necessary as MAXINT * 2 is
MAXUINT - 1 and the size parameter of GlobalAlloc is unsigned.

But the * sizeof(WCHAR) in the GlobalAlloc call is necessary to avoid
possible memory corruption because of buffer overruns. So here is it.

  Michael