[FFmpeg-cvslog] avcodec/ffwavesynth: Fix integer overflow for some corner case values

[Michael Niedermayer]

ffmpeg | branch: release/4.2 | Michael Niedermayer <michael at niedermayer.cc> | Sat Aug 10 23:09:44 2019 +0200| [bcc1fe5165b21d6039c5be87e8ee8c25de1339d6] | committer: Michael Niedermayer

avcodec/ffwavesynth: Fix integer overflow for some corner case values

Fixes: left shift of negative value -14671840
Fixes: 16000/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_FFWAVESYNTH_fuzzer-5145977817661440

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit c4a88fb546b64179aff12c169239285932e570ac)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=bcc1fe5165b21d6039c5be87e8ee8c25de1339d6
---

 libavcodec/ffwavesynth.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/ffwavesynth.c b/libavcodec/ffwavesynth.c
index b319b3341a..e6d2606c2f 100644
--- a/libavcodec/ffwavesynth.c
+++ b/libavcodec/ffwavesynth.c
@@ -301,8 +301,8 @@ static int wavesynth_parse_extradata(AVCodecContext *avc)
             default:
                 return AVERROR(EINVAL);
         }
-        in->amp0 = (int64_t)a1 << 32;
-        in->damp = (((int64_t)a2 << 32) - ((int64_t)a1 << 32)) / dt;
+        in->amp0 = (uint64_t)a1 << 32;
+        in->damp = (int64_t)(((uint64_t)a2 << 32) - ((uint64_t)a1 << 32)) / dt;
     }
     if (edata != edata_end)
         return AVERROR(EINVAL);