From 9033920bec9ccf17de205fc17c2b330906b200f5 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Tue, 17 Apr 2018 02:13:43 +0200 Subject: [PATCH] avcodec/cinepak: Skip empty frames Speeds up decoding from 3 to 0.1 seconds for 6302/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_CINEPAK_fuzzer-5626371985375232 Fixes: Timeout Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/cinepak.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/libavcodec/cinepak.c b/libavcodec/cinepak.c index ba0589582f..9b0077402f 100644 --- a/libavcodec/cinepak.c +++ b/libavcodec/cinepak.c @@ -444,6 +444,7 @@ static int cinepak_decode_frame(AVCodecContext *avctx, const uint8_t *buf = avpkt->data; int ret = 0, buf_size = avpkt->size; CinepakContext *s = avctx->priv_data; + int num_strips; s->data = buf; s->size = buf_size; @@ -451,6 +452,12 @@ static int cinepak_decode_frame(AVCodecContext *avctx, if (s->size < 10) return AVERROR_INVALIDDATA; + num_strips = AV_RB16 (&s->data[8]); + + //Empty frame, do not waste time + if (!num_strips && (!s->palette_video || !av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL))) + return buf_size; + if ((ret = cinepak_predecode_check(s)) < 0) { av_log(avctx, AV_LOG_ERROR, "cinepak_predecode_check failed\n"); return ret;