From 8b8f5fd05e7e0c20b2fd12e8a4e9f2542eba7e3a Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sun, 4 Aug 2019 09:33:45 +0200 Subject: [PATCH] avcodec/mss3: Check for the rac stream being invalid in rac_normalize() Fixes: out of array read Fixes: 15982/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MSA1_fuzzer-5630676251967488 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit 99a172f3f4d0bef024c6293f575caaaddce0b267) Signed-off-by: Michael Niedermayer --- libavcodec/mss3.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/libavcodec/mss3.c b/libavcodec/mss3.c index 21226f9085..02bd360996 100644 --- a/libavcodec/mss3.c +++ b/libavcodec/mss3.c @@ -298,6 +298,10 @@ static void rac_normalise(RangeCoder *c) c->got_error = 1; c->low = 1; } + if (c->low > c->range) { + c->got_error = 1; + c->low = 1; + } if (c->range >= RAC_BOTTOM) return; }