[FFmpeg-cvslog] avcodec/fic: Check that there is input left in fic_decode_block()

[Michael Niedermayer]

ffmpeg | branch: release/4.1 | Michael Niedermayer <michael at niedermayer.cc> | Wed Jan 23 00:30:53 2019 +0100| [f5c9753bfdab20ad54fbdbbe85b52c82d0bb3c4b] | committer: Michael Niedermayer

avcodec/fic: Check that there is input left in fic_decode_block()

Fixes: Timeout
Fixes: 12450/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_FIC_fuzzer-5661984622641152

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit db1c4acd02af4de5dfbea6012c296470679aa7a6)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=f5c9753bfdab20ad54fbdbbe85b52c82d0bb3c4b
---

 libavcodec/fic.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libavcodec/fic.c b/libavcodec/fic.c
index 3e36346358..418dff1934 100644
--- a/libavcodec/fic.c
+++ b/libavcodec/fic.c
@@ -139,6 +139,9 @@ static int fic_decode_block(FICContext *ctx, GetBitContext *gb,
 {
     int i, num_coeff;
 
+    if (get_bits_left(gb) < 8)
+        return AVERROR_INVALIDDATA;
+
     /* Is it a skip block? */
     if (get_bits1(gb)) {
         *is_p = 1;