From efeb47fd5d5cbf980e52a6d5e741c3c74b94b5e2 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sun, 21 May 2017 16:01:27 +0200 Subject: [PATCH] avcodec/mpeg4videodec: Check for multiple VOL headers Fixes multiple: runtime error: signed integer overflow: 2147115008 + 413696 cannot be represented in type 'int' Fixes: 1723/clusterfuzz-testcase-minimized-5309409372667904 Fixes: 1727/clusterfuzz-testcase-minimized-5900685306494976 Fixes: 1737/clusterfuzz-testcase-minimized-5922321338466304 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/mpeg4videodec.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/libavcodec/mpeg4videodec.c b/libavcodec/mpeg4videodec.c index 54b7be10dd..1e22165c0b 100644 --- a/libavcodec/mpeg4videodec.c +++ b/libavcodec/mpeg4videodec.c @@ -2566,6 +2566,7 @@ int ff_mpeg4_decode_picture_header(Mpeg4DecContext *ctx, GetBitContext *gb) MpegEncContext *s = &ctx->m; unsigned startcode, v; int ret; + int vol = 0; /* search next start code */ align_get_bits(gb); @@ -2654,6 +2655,11 @@ int ff_mpeg4_decode_picture_header(Mpeg4DecContext *ctx, GetBitContext *gb) } if (startcode >= 0x120 && startcode <= 0x12F) { + if (vol) { + av_log(s->avctx, AV_LOG_ERROR, "Multiple VOL headers"); + return AVERROR_INVALIDDATA; + } + vol++; if ((ret = decode_vol_header(ctx, gb)) < 0) return ret; } else if (startcode == USER_DATA_STARTCODE) {