Mailing List Archive: Wrong type for memory allocation calculation

Hello,

I'm new here, so please forgive me if I'm posting to the wrong list!

I think have found a bug in fmap.c which causes a crash when scanning a
large file in a 64 bit build.

The function cl_fmap_open_handle uses an unsigned for mapsz (line 213),
and then calculates the size (line 232) with

mapsz = pages * pgsz + hdrsz;

Where I had a crash, pages was 1047561, pgsz was 4096 and hdrsz was
4194304, so the result (4,295,004,160) overflowed an unsigned.

These variables should be size_t (the correct size type for mmap).

--
Ian.

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Ian,

Thanks for the report. We are looking into the problem.

Steve

On Mon, Feb 24, 2014 at 3:08 AM, Ian Collins <ian@ianshome.com> wrote:

> Hello,
>
> I'm new here, so please forgive me if I'm posting to the wrong list!
>
> I think have found a bug in fmap.c which causes a crash when scanning a
> large file in a 64 bit build.
>
> The function cl_fmap_open_handle uses an unsigned for mapsz (line 213),
> and then calculates the size (line 232) with
>
> mapsz = pages * pgsz + hdrsz;
>
> Where I had a crash, pages was 1047561, pgsz was 4096 and hdrsz was
> 4194304, so the result (4,295,004,160) overflowed an unsigned.
>
> These variables should be size_t (the correct size type for mmap).
>
> --
> Ian.
>
> _______________________________________________
> http://lurker.clamav.net/list/clamav-devel.html
> Please submit your patches to our Bugzilla: http://bugs.clamav.net
>
_______________________________________________
http://lurker.clamav.net/list/clamav-devel.html
Please submit your patches to our Bugzilla: http://bugs.clamav.net