[FFmpeg-cvslog] avcodec/faxcompr: Check for end of input in cmode == 1 in decode_group3_2d_line()

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Sat Jul 31 21:17:23 2021 +0200| [f803635c4fac761ac68b39a369272d4c26433dc1] | committer: Michael Niedermayer

avcodec/faxcompr: Check for end of input in cmode == 1 in decode_group3_2d_line()

Fixes: Infinite loop
Fixes: 35591/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_TIFF_fuzzer-4503764022198272

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=f803635c4fac761ac68b39a369272d4c26433dc1
---

 libavcodec/faxcompr.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libavcodec/faxcompr.c b/libavcodec/faxcompr.c
index 44c1f6f6b9..b283831dae 100644
--- a/libavcodec/faxcompr.c
+++ b/libavcodec/faxcompr.c
@@ -283,6 +283,8 @@ static int decode_group3_2d_line(AVCodecContext *avctx, GetBitContext *gb,
             for (k = 0; k < 2; k++) {
                 run = 0;
                 for (;;) {
+                    if (get_bits_left(gb) <= 0)
+                        return AVERROR_INVALIDDATA;
                     t = get_vlc2(gb, ccitt_vlc[mode].table, 9, 2);
                     if (t == -1) {
                         av_log(avctx, AV_LOG_ERROR, "Incorrect code\n");