From aa3cdf2a569bf8311510b232639b1f7a0882f0e8 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Thu, 11 Feb 2021 22:44:36 +0100 Subject: [PATCH] avformat/jacosubdec: Use 64bit intermediate for start/end timestamp shift Fixes: signed integer overflow: -1957694447 + -1620425806 cannot be represented in type 'int' Fixes: 30207/clusterfuzz-testcase-minimized-ffmpeg_dem_JACOSUB_fuzzer-5050791771635712 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit 2c477be08a64a78ab0a358ae00e2f2dc746f2b47) Signed-off-by: Michael Niedermayer --- libavformat/jacosubdec.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libavformat/jacosubdec.c b/libavformat/jacosubdec.c index e70ceeaafd..c3cfc2f27e 100644 --- a/libavformat/jacosubdec.c +++ b/libavformat/jacosubdec.c @@ -125,8 +125,8 @@ static const char *read_ts(JACOsubContext *jacosub, const char *buf, return NULL; shift_and_ret: - ts_start64 = (ts_start + jacosub->shift) * 100LL / jacosub->timeres; - ts_end64 = (ts_end + jacosub->shift) * 100LL / jacosub->timeres; + ts_start64 = (ts_start + (int64_t)jacosub->shift) * 100LL / jacosub->timeres; + ts_end64 = (ts_end + (int64_t)jacosub->shift) * 100LL / jacosub->timeres; *start = ts_start64; *duration = ts_end64 - ts_start64; return buf + len;