sön 2022-11-13 klockan 00:44 +0100 skrev Michael Niedermayer: > Fixes: signed integer overflow: -3741319169 - 9223372036823449370 > cannot be represented in type 'long' > Fixes: 51896/clusterfuzz-testcase-minimized-ffmpeg_dem_MXF_fuzzer- > 513039428681728 > > Found-by: continuous fuzzing process > https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > Signed-off-by: Michael Niedermayer <mich...@niedermayer.cc> > --- > libavformat/mxfdec.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) > > diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c > index e6118e141d..42109cb43a 100644 > --- a/libavformat/mxfdec.c > +++ b/libavformat/mxfdec.c > @@ -100,7 +100,7 @@ typedef struct MXFPartition { > uint64_t previous_partition; > int index_sid; > int body_sid; > - int64_t this_partition; > + uint64_t this_partition; > int64_t essence_offset; ///< absolute offset of essence > int64_t essence_length; > int32_t kag_size; > @@ -3519,8 +3519,12 @@ static void > mxf_compute_essence_containers(AVFormatContext *s) > p->essence_offset = p->first_essence_klv.offset; > > /* essence container spans to the next partition */ > - if (x < mxf->partitions_count - 1) > - p->essence_length = mxf- > >partitions[x+1].this_partition - p->essence_offset; > + if (x < mxf->partitions_count - 1) { > + if (mxf->partitions[x+1].this_partition < p- > >essence_offset) { > + p->essence_length = -1; > + } else > + p->essence_length = mxf- > >partitions[x+1].this_partition - p->essence_offset; > + }
A better solution might be to record the actual offset of the partitions rather than relying on ThisPartition. Then we can guarantee that they are strictly increasing. /Tomas _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
