From 7560bd30bad9529e89f9bfd8308039bbee2c9edd Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Mon, 22 Feb 2021 20:20:48 +0100 Subject: [PATCH] avformat/mvi: Check audio size for more overflows Fixes: left shift of negative value -352256000 Fixes: 30837/clusterfuzz-testcase-minimized-ffmpeg_dem_MVI_fuzzer-5755626262888448 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit 403b35e16e16a8c4a13e531ccdc23598f685ca20) Signed-off-by: Michael Niedermayer --- libavformat/mvi.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/libavformat/mvi.c b/libavformat/mvi.c index 0b53473671..6aad6cb86a 100644 --- a/libavformat/mvi.c +++ b/libavformat/mvi.c @@ -119,6 +119,10 @@ static int read_packet(AVFormatContext *s, AVPacket *pkt) mvi->video_frame_size = (mvi->get_int)(pb); if (mvi->audio_size_left == 0) return AVERROR(EIO); + if (mvi->audio_size_counter + 512 > UINT64_MAX - mvi->audio_frame_size || + mvi->audio_size_counter + 512 + mvi->audio_frame_size >= ((uint64_t)INT32_MAX) << MVI_FRAC_BITS) + return AVERROR_INVALIDDATA; + count = (mvi->audio_size_counter + mvi->audio_frame_size + 512) >> MVI_FRAC_BITS; if (count > mvi->audio_size_left) count = mvi->audio_size_left;