[FFmpeg-devel] [PATCH 2/5] avcodec/wavpack: Fix overflow in k=31

[Paul B Mahol]

On Thu, Dec 1, 2022 at 8:56 PM Michael Niedermayer <michael at niedermayer.cc>
wrote:

> On Wed, Nov 30, 2022 at 09:39:44PM +0100, Paul B Mahol wrote:
> > On 9/11/22, Michael Niedermayer <michael at niedermayer.cc> wrote:
> > > Untested with "non fuzzed" samples as i have no such file
> > >
> >
> > Then create it.
>
> the official WavPack-5.6.0 decoder has 2 alternative optimized codepathes
> #ifdef USE_BITMASK_TABLES
>     extras = bitset [bitcount] - maxcode - 1;
> #else
>     extras = (1 << bitcount) - maxcode - 1;
> #endif
>
> The 2nd path would result in the same 1<<32 which is undefined but luckily
> the first seems hardcoded to be used it uses this table:
>
> const uint32_t bitset [] = {
>     1L << 0, 1L << 1, 1L << 2, 1L << 3,
>     1L << 4, 1L << 5, 1L << 6, 1L << 7,
>     1L << 8, 1L << 9, 1L << 10, 1L << 11,
>     1L << 12, 1L << 13, 1L << 14, 1L << 15,
>     1L << 16, 1L << 17, 1L << 18, 1L << 19,
>     1L << 20, 1L << 21, 1L << 22, 1L << 23,
>     1L << 24, 1L << 25, 1L << 26, 1L << 27,
>     1L << 28, 1L << 29, 1L << 30, 1L << 31
> };
>
> here bitset[32] is out of array
>
> Given above i suspect no valid file should use this. Otherwise something
> seriously odd is going on.
>
> also the subject has a typo its p=31 not k=31
>
> thx
>

OK


>
> [...]
>
> --
> Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
>
> The real ebay dictionary, page 2
> "100% positive feedback" - "All either got their money back or didnt
> complain"
> "Best seller ever, very honest" - "Seller refunded buyer after failed scam"
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request at ffmpeg.org with subject "unsubscribe".
>