[FFmpeg-cvslog] avcodec/binkaudio: reset ch_offset on errors

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Mon Mar 28 20:27:20 2022 +0200| [3a22bc03e6b1813a8388c39137150f322f9119f6] | committer: Michael Niedermayer

avcodec/binkaudio: reset ch_offset on errors

Fixes: NULL pointer dereference
Fixes: 45955/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_BINKAUDIO_DCT_fuzzer-4842044192849920

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Paul B Mahol <onemda at gmail.com>
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=3a22bc03e6b1813a8388c39137150f322f9119f6
---

 libavcodec/binkaudio.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libavcodec/binkaudio.c b/libavcodec/binkaudio.c
index 56b58b57c8..c4f3e743e2 100644
--- a/libavcodec/binkaudio.c
+++ b/libavcodec/binkaudio.c
@@ -329,6 +329,7 @@ again:
                      avctx->codec->id == AV_CODEC_ID_BINKAUDIO_DCT,
                      FFMIN(MAX_CHANNELS, s->channels - s->ch_offset), s->ch_offset)) {
         av_log(avctx, AV_LOG_ERROR, "Incomplete packet\n");
+        s->ch_offset = 0;
         return AVERROR_INVALIDDATA;
     }
     s->ch_offset += MAX_CHANNELS;
@@ -347,6 +348,7 @@ again:
 
     return 0;
 fail:
+    s->ch_offset = 0;
     av_packet_unref(s->pkt);
     return ret;
 }