[FFmpeg-devel] [PATCH 06/11] avutil/eval: Unconditionally check argument of e_div

[Andreas Rheinhardt]

Michael Niedermayer:
> Fixes: division by zero
> Fixes: 26451/clusterfuzz-testcase-minimized-ffmpeg_dem_VIVO_fuzzer-4756955832516608
> 
> Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
> Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> ---
>  libavutil/eval.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/libavutil/eval.c b/libavutil/eval.c
> index d527f6a9d0..aaa8eb4945 100644
> --- a/libavutil/eval.c
> +++ b/libavutil/eval.c
> @@ -317,7 +317,7 @@ static double eval_expr(Parser *p, AVExpr *e)
>                  case e_lte: return e->value * (d <= d2 ? 1.0 : 0.0);
>                  case e_pow: return e->value * pow(d, d2);
>                  case e_mul: return e->value * (d * d2);
> -                case e_div: return e->value * ((!CONFIG_FTRAPV || d2 ) ? (d / d2) : d * INFINITY);
> +                case e_div: return e->value * (d2 ? (d / d2) : d * INFINITY);
>                  case e_add: return e->value * (d + d2);
>                  case e_last:return e->value * d2;
>                  case e_st : return e->value * (p->var[av_clip(d, 0, VARS-1)]= d2);
> 
What division by zero (does the fuzzer complain about floating point
division by zero?)?

- Andreas