[FFmpeg-cvslog] avfilter/vf_dctdnoiz: Check threads

[Michael Niedermayer]

ffmpeg | branch: release/4.4 | Michael Niedermayer <michael at niedermayer.cc> | Sat Jun  5 20:00:38 2021 +0200| [79b69b5f4c7f4577972d1dd3accd736b48c91969] | committer: Michael Niedermayer

avfilter/vf_dctdnoiz: Check threads

Fixes: floating point division by 0
Fixes: Ticket 8269

Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit 4a3917c02c428b11128ac3d4a01b780ea44aa53c)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=79b69b5f4c7f4577972d1dd3accd736b48c91969
---

 libavfilter/vf_dctdnoiz.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libavfilter/vf_dctdnoiz.c b/libavfilter/vf_dctdnoiz.c
index a89f2631c8..2019a5b456 100644
--- a/libavfilter/vf_dctdnoiz.c
+++ b/libavfilter/vf_dctdnoiz.c
@@ -564,6 +564,9 @@ static int config_input(AVFilterLink *inlink)
                inlink->h - s->pr_height);
 
     max_slice_h = s->pr_height / ((s->bsize - 1) * 2);
+    if (max_slice_h == 0)
+        return AVERROR(EINVAL);
+
     s->nb_threads = FFMIN3(MAX_THREADS, ff_filter_get_nb_threads(ctx), max_slice_h);
     av_log(ctx, AV_LOG_DEBUG, "threads: [max=%d hmax=%d user=%d] => %d\n",
            MAX_THREADS, max_slice_h, ff_filter_get_nb_threads(ctx), s->nb_threads);