From cf5a6c754aa3b67062b8cc60fa244e9c7d82010f Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Wed, 1 Nov 2017 20:02:59 +0100 Subject: [PATCH] avcodec/gdv: Check compression before allocating frame Fixes: 2926/clusterfuzz-testcase-4987110014582784 This reduces decoding time from 7 to 4 seconds The timeout should have been fixed in 0561bd2fc2bff0dbe651d5998e9f129c43d25eb3 but ossfuzz did not close this issue Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Reviewed-by: Paul B Mahol Signed-off-by: Michael Niedermayer --- libavcodec/gdv.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/libavcodec/gdv.c b/libavcodec/gdv.c index dc91869edf..e52a637610 100644 --- a/libavcodec/gdv.c +++ b/libavcodec/gdv.c @@ -409,17 +409,20 @@ static int gdv_decode_frame(AVCodecContext *avctx, void *data, unsigned flags; uint8_t *dst; - if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) - return ret; - if (pal && pal_size == AVPALETTE_SIZE) - memcpy(gdv->pal, pal, AVPALETTE_SIZE); - bytestream2_init(gb, avpkt->data, avpkt->size); bytestream2_init_writer(pb, gdv->frame, gdv->frame_size); flags = bytestream2_get_le32(gb); compression = flags & 0xF; + if (compression == 4 || compression == 7 || compression > 8) + return AVERROR_INVALIDDATA; + + if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) + return ret; + if (pal && pal_size == AVPALETTE_SIZE) + memcpy(gdv->pal, pal, AVPALETTE_SIZE); + rescale(gdv, gdv->frame, avctx->width, avctx->height, !!(flags & 0x10), !!(flags & 0x20)); @@ -451,7 +454,7 @@ static int gdv_decode_frame(AVCodecContext *avctx, void *data, ret = decompress_68(avctx, flags >> 8, 1); break; default: - return AVERROR_INVALIDDATA; + av_assert0(0); } memcpy(frame->data[1], gdv->pal, AVPALETTE_SIZE);