From cf1b7ab0ec7df60fe725fe89f7abe08f59485536 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Fri, 29 Mar 2024 03:35:18 +0100 Subject: [PATCH] avformat/mxfdec: Check first case of offset_temp computation for overflow This is kind of ugly Fixes: signed integer overflow: 255 * 1157565362826411919 cannot be represented in type 'long' Fixes: 67313/clusterfuzz-testcase-minimized-ffmpeg_dem_MXF_fuzzer-6250434245230592 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit d6ed6f6e8dffcf777c336869f56002da588e2de8) Signed-off-by: Michael Niedermayer --- libavformat/mxfdec.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c index 4111c6565b..290e1fc4fa 100644 --- a/libavformat/mxfdec.c +++ b/libavformat/mxfdec.c @@ -1601,9 +1601,13 @@ static int mxf_edit_unit_absolute_offset(MXFContext *mxf, MXFIndexTable *index_t if (edit_unit < s->index_start_position + s->index_duration) { int64_t index = edit_unit - s->index_start_position; - if (s->edit_unit_byte_count) + if (s->edit_unit_byte_count) { + if (index > INT64_MAX / s->edit_unit_byte_count || + s->edit_unit_byte_count * index > INT64_MAX - offset_temp) + return AVERROR_INVALIDDATA; + offset_temp += s->edit_unit_byte_count * index; - else { + } else { if (s->nb_index_entries == 2 * s->index_duration + 1) index *= 2; /* Avid index */