[FFmpeg-devel] [PATCH 1/3] aacsbr_fixed: avoid division by zero in sbr_gain_calc

[Michael Niedermayer]

On Sun, Nov 08, 2015 at 10:02:56PM +0100, Andreas Cadhalpun wrote:
> This fixes a SIGFPE crash in the aac_fixed decoder.
> 
> Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun at googlemail.com>
> ---
>  libavcodec/aacsbr_fixed.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/libavcodec/aacsbr_fixed.c b/libavcodec/aacsbr_fixed.c
> index f942d74..efe40f2 100644
> --- a/libavcodec/aacsbr_fixed.c
> +++ b/libavcodec/aacsbr_fixed.c
> @@ -434,8 +434,8 @@ static void sbr_gain_calc(AACContext *ac, SpectralBandReplication *sbr,
>                gain_max = FLOAT_100000;
>              for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
>                  SoftFloat q_m_max = av_div_sf(
> -                                        av_mul_sf(sbr->q_m[e][m], gain_max),
> -                                        sbr->gain[e][m]);
> +                                        av_add_sf(FLOAT_EPSILON, av_mul_sf(sbr->q_m[e][m], gain_max)),
> +                                        av_add_sf(FLOAT_EPSILON, sbr->gain[e][m]));

is gain == 0 here ?
isnt that invalid ?

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

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