From 6b67d7f05918f7a1ee8fc6ff21355d7e8736aa10 Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michael@niedermayer.cc>
Date: Sat, 28 Jul 2018 15:03:50 +0200
Subject: [PATCH] avformat/flvenc: Check audio packet size

Fixes: Assertion failure
Fixes: assert_flvenc.c:941_1.swf

Upstream-Status: Backport [https://github.com/FFmpeg/FFmpeg/commit/6b67d7f05918f7a1ee8fc6ff21355d7e8736aa10]
CVE: CVE-2018-15822

Found-by: #CHEN HONGXU# <HCHEN017@e.ntu.edu.sg>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Mingli Yu <Mingli.Yu@windriver.com>
---
 libavformat/flvenc.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/libavformat/flvenc.c b/libavformat/flvenc.c
index 1c552a3e6b..e4863f1fc7 100644
--- a/libavformat/flvenc.c
+++ b/libavformat/flvenc.c
@@ -883,6 +883,11 @@ static int flv_write_packet(AVFormatContext *s, AVPacket *pkt)
     int flags = -1, flags_size, ret;
     int64_t cur_offset = avio_tell(pb);
 
+    if (par->codec_type == AVMEDIA_TYPE_AUDIO && !pkt->size) {
+        av_log(s, AV_LOG_WARNING, "Empty audio Packet\n");
+        return AVERROR(EINVAL);
+    }
+
     if (par->codec_id == AV_CODEC_ID_VP6F || par->codec_id == AV_CODEC_ID_VP6A ||
         par->codec_id == AV_CODEC_ID_VP6  || par->codec_id == AV_CODEC_ID_AAC)
         flags_size = 2;
-- 
2.17.1

