From 6ebb9e7b7765d699692ba18c2b0ef1ff1ce6dbf4 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Wed, 17 May 2017 01:12:55 +0200 Subject: [PATCH] avcodec/flicvideo: Check frame_size before decrementing Fixes: runtime error: signed integer overflow: -2147483627 - 22 cannot be represented in type 'int' Fixes: 1637/clusterfuzz-testcase-minimized-5376582493405184 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit 355e27e24dc88d6ba8f27501a34925d9d937a399) Signed-off-by: Michael Niedermayer --- libavcodec/flicvideo.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/libavcodec/flicvideo.c b/libavcodec/flicvideo.c index b1b7b5a42f..46fd21d2b1 100644 --- a/libavcodec/flicvideo.c +++ b/libavcodec/flicvideo.c @@ -199,6 +199,9 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx, num_chunks = bytestream2_get_le16(&g2); bytestream2_skip(&g2, 8); /* skip padding */ + if (frame_size < 16) + return AVERROR_INVALIDDATA; + frame_size -= 16; /* iterate through the chunks */ @@ -519,6 +522,8 @@ static int flic_decode_frame_15_16BPP(AVCodecContext *avctx, if (frame_size > buf_size) frame_size = buf_size; + if (frame_size < 16) + return AVERROR_INVALIDDATA; frame_size -= 16; /* iterate through the chunks */ @@ -804,6 +809,8 @@ static int flic_decode_frame_24BPP(AVCodecContext *avctx, if (frame_size > buf_size) frame_size = buf_size; + if (frame_size < 16) + return AVERROR_INVALIDDATA; frame_size -= 16; /* iterate through the chunks */