From 7d8421e3d5bc1300687a65384baccbcb3874b7ac Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Wed, 9 Jun 2021 21:20:04 +0200 Subject: [PATCH] avcodec/faxcompr: Check if bits are available before reading in cmode == 9 || cmode == 10 Fixes: Timeout Fixes: 34950/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_TIFF_fuzzer-5686764151898112 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/faxcompr.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/libavcodec/faxcompr.c b/libavcodec/faxcompr.c index d44de2485d..45e0c482d7 100644 --- a/libavcodec/faxcompr.c +++ b/libavcodec/faxcompr.c @@ -304,7 +304,10 @@ static int decode_group3_2d_line(AVCodecContext *avctx, GetBitContext *gb, mode = !mode; } } else if (cmode == 9 || cmode == 10) { - int xxx = get_bits(gb, 3); + int xxx; + if (get_bits_left(gb) < 3) + return AVERROR_INVALIDDATA; + xxx = get_bits(gb, 3); if (cmode == 9 && xxx == 7) { int ret; int pix_left = width - offs;