From 07519f363bbd810e6ac8b187628e680e4e7026ca Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sat, 20 Jul 2019 23:37:38 +0200 Subject: [PATCH] avcodec/hqx: Check the input data against the image size Fixes: Timeout (22 -> 100 ms) Fixes: 15173/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_HQX_fuzzer-5662556846292992 Fixes: 17896/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_HQX_fuzzer-5679312077848576 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/hqx.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/libavcodec/hqx.c b/libavcodec/hqx.c index bc24ba91d1..39404d24e5 100644 --- a/libavcodec/hqx.c +++ b/libavcodec/hqx.c @@ -471,6 +471,14 @@ static int hqx_decode_frame(AVCodecContext *avctx, void *data, avctx->height = ctx->height; avctx->bits_per_raw_sample = 10; + //The minimum size is 2bit per macroblock + // hqx_decode_422 & hqx_decode_444 have a unconditionally stored 4bits hqx_quants index + // hqx_decode_422a & hqx_decode_444a use cbp_vlc which has a minimum length of 2 bits for its VLCs + // The code rejects slices overlapping in their input data + if (avctx->coded_width / 16 * (avctx->coded_height / 16) * + (100 - avctx->discard_damaged_percentage) / 100 > 4LL * avpkt->size) + return AVERROR_INVALIDDATA; + switch (ctx->format) { case HQX_422: avctx->pix_fmt = AV_PIX_FMT_YUV422P16;