avformat/mov: Break out early if chunk_count is 0 in mov_build_index()

Without this some operations might overflow (undefined behavior)
even though the index adding loop would never execute

No testcase known

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 56e76bd0579cc7f7b28860885d9e569a39daf41b)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2018-05-15 17:06:59 +02:00
parent fe9c23bebb
commit b4024909c1

View File

@ -2829,6 +2829,9 @@ static void mov_build_index(MOVContext *mov, AVStream *st)
} else {
unsigned chunk_samples, total = 0;
if (!sc->chunk_count)
return;
// compute total chunk count
for (i = 0; i < sc->stsc_count; i++) {
unsigned count, chunk_count;