From 06a90cc78385d87b346be23efc9081eb08936c18 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Fri, 7 Jun 2019 22:43:42 +0200 Subject: [PATCH] avformat/jacosubdec: Fix timeres to 1/100 units convertion overflow Fixes: signed integer overflow: 44444442 * 100 cannot be represented in type 'int' Fixes: 15117/clusterfuzz-testcase-minimized-ffmpeg_DEMUXER_fuzzer-5164660531134464 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavformat/jacosubdec.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/libavformat/jacosubdec.c b/libavformat/jacosubdec.c index 50144f7e21..121c86d659 100644 --- a/libavformat/jacosubdec.c +++ b/libavformat/jacosubdec.c @@ -107,6 +107,7 @@ static const char *read_ts(JACOsubContext *jacosub, const char *buf, unsigned hs, ms, ss, fs; // hours, minutes, seconds, frame start unsigned he, me, se, fe; // hours, minutes, seconds, frame end int ts_start, ts_end; + int64_t ts_start64, ts_end64; /* timed format */ if (sscanf(buf, "%u:%u:%u.%u %u:%u:%u.%u %n", @@ -124,10 +125,10 @@ static const char *read_ts(JACOsubContext *jacosub, const char *buf, return NULL; shift_and_ret: - ts_start = (ts_start + jacosub->shift) * 100 / jacosub->timeres; - ts_end = (ts_end + jacosub->shift) * 100 / jacosub->timeres; - *start = ts_start; - *duration = ts_end - ts_start; + ts_start64 = (ts_start + jacosub->shift) * 100LL / jacosub->timeres; + ts_end64 = (ts_end + jacosub->shift) * 100LL / jacosub->timeres; + *start = ts_start64; + *duration = ts_end64 - ts_start64; return buf + len; }