[FFmpeg-devel] [PATCH 5/6] avcodec/utils: Check ima wav duration for overflow

[Michael Niedermayer]

Fixes: signed integer overflow: 44331634 * 65 cannot be represented in type 'int'
Fixes: 32120/clusterfuzz-testcase-minimized-ffmpeg_dem_RSD_fuzzer-5760221223583744

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavcodec/utils.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/libavcodec/utils.c b/libavcodec/utils.c
index 896b99dc3f..6cd8b9629a 100644
--- a/libavcodec/utils.c
+++ b/libavcodec/utils.c
@@ -773,11 +773,15 @@ static int get_audio_frame_duration(enum AVCodecID id, int sr, int ch, int ba,
             if (ba > 0) {
                 /* calc from frame_bytes, channels, and block_align */
                 int blocks = frame_bytes / ba;
+                int64_t tmp;
                 switch (id) {
                 case AV_CODEC_ID_ADPCM_IMA_WAV:
                     if (bps < 2 || bps > 5)
                         return 0;
-                    return blocks * (1 + (ba - 4 * ch) / (bps * ch) * 8);
+                    tmp = blocks * (1LL + (ba - 4 * ch) / (bps * ch) * 8);
+                    if (tmp != (int)tmp)
+                        return 0;
+                    return tmp;
                 case AV_CODEC_ID_ADPCM_IMA_DK3:
                     return blocks * (((ba - 16) * 2 / 3 * 4) / ch);
                 case AV_CODEC_ID_ADPCM_IMA_DK4:
-- 
2.17.1